Cylinder pump, an ink jet printing system using the cylinder pump and a photograph assembly having the printing system

Information

  • Patent Grant
  • 6769763
  • Patent Number
    6,769,763
  • Date Filed
    Friday, September 7, 2001
    22 years ago
  • Date Issued
    Tuesday, August 3, 2004
    19 years ago
Abstract
Down-sizing of a pump for sucking two types of different fluids is realized. The pump is provided with a cylinder pump having a cylinder main body having a reciprocally movable piston, a first cylinder chamber partitioned at one side of the piston for being introduced with a first fluid, and a second cylinder chamber partitioned at the other side of the piston for being introduced with a second fluid, and piston driving means for reciprocally moving the piston of the cylinder pump.
Description




This application is based on Japanese Patent Application Nos. 2000-277226 filed Sep. 12, 2000 and 2001-081642 filed Mar. 21, 2001, the content of which is incorporated hereinto by reference.




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to a cylinder pump suitable for sucking two different types of liquid and an ink jet printing system using the cylinder pump, specifically to an improvement for down-sizing of the cylinder pump. The present invention further relates to a photograph assembly having an ink jet printing system provided with the down-sized cylinder pump.




2. Description of the Prior Art




As an ink jet printing system, there has heretofore been a so-called serial scan type equipped replaceably with a recording head as recording means and an ink tank as an ink vessel on a carriage movable in a main scanning direction. This printing method successively prints an image on a printing medium by repeating main scanning of a carriage equipped with the recording head and an ink tank and sub-scanning of the printing medium.




When considering realization of an ultra-compact printer suitable for use in PDA (Personal Digital Assistants) or cameras, it is necessary to reduce the size of the carriage itself. Therefore, the ink volume of the ink tank equipped thereon must be extremely small.




When the ink tank volume on the carriage is extremely small as described above, there is a possibility of generating a problem in that replacement frequency of the ink tank becomes high or the ink tank must be replaced in the course of printing operation.




Then, in order to solve such a problem, there is proposed an ink supply method in which ink is supplied from a separately provided main tank to a sub-tank on the carriage at an appropriate timing every time the carriage is positioned at a predetermined stand-by position, hereinafter for convenience called a pit-in ink supply method.




In this pit-in ink supply method, for example, every time a sheet of printing medium is printed, the carriage is positioned at a predetermined stand-by position, the sub-tank on the carriage and the main tank are connected at an appropriate timing, so that with this connection state, ink is supplied from the main tank to the sub-tank. By this operation, the above-described problem with the ink volume of the sub-tank on the carriage is solved.




In the above-described pit-in ink supply method, an ink absorber such as a sponge is provided inside the sub-tank, ink supply is performed by a negative pressure introduced from an air suction opening to the inside, so that ink is introduced from the main tank into the sub-tank through the ink intake.




Further, in the ink jet printing method, when air influxes into the nozzle of the recording head, or when ink increases in viscosity by drying or the like, the nozzle becomes ink ejection impossible, and ink droplets cannot be ejected from such a nozzle. Therefore, a capping member for covering a face of the recording head and suction means for sucking ink from the nozzle of the recording head through the capping member are provided so that ink which does not contribute to image printing is sucked and removed from the tip of the nozzle at an appropriate time.




As described above, in ink jet printing using the pit-in ink supply method, a suction pump is required for sucking air for ink supply and for sucking ink from the recording head.




As the suction pump, there has heretofore been a tube pump for generating a negative pressure in the cap utilizing the restoration force of a tube squeezed by a roller or a piston pump utilizing a movement of a piston, or the like.




In the case of the tube pump, since a rotary mechanism for rotating the roller for squeezing the tube is required, the mechanism itself becomes large in size. Therefore, it is not suited as a suction pump for the above-described ultra-compact printer.




In the case of the piston pump, since it is a reciprocal type, it is suited as a suction pump for ultra-compact printer. However, also in the case of the piston pump, there are problems of requiring a suction pump which is large in construction such that,




(1) separate pumps are used for ink suction and air suction,




(2) when a common pump is used for ink suction and air suction, a suction switching construction is necessary for switching the ink suction passage and the air suction passage for connecting to the input port of the pump.




As described above, for realizing an ultra-compact ink jet printer suitable for PDA or camera, construction of the suction pump part suitable for ultra-compact structure has been in demand.




Under such circumstances, it is therefore an object of the present invention to provide a cylinder pump which can be constructed small in structure and is suitable for sucking two different types of liquid and an ink jet printing system using the cylinder pump.




SUMMARY OF THE INVENTION




In an aspect of the present invention, a cylinder pump unit comprises a cylinder pump and a piston driving means. The cylinder pump includes a reciprocally movable piston and a cylinder main body having a first cylinder chamber partitioned at one side of the piston and introduced with a first fluid and a second cylinder chamber partitioned at the other side of the piston and introduced with a second fluid.




The piston driving means reciprocally moves the piston of the cylinder pump.




In another aspect of the present invention, the first fluid is air, the second fluid is ink and a piston shaft of the piston is extended to outside the cylinder main body through the second cylinder chamber and connected to the piston drive means.




In another aspect of the present invention, the second cylinder chamber has an input port for sucking ink and an output port for discharging ink. A cylinder pump unit further comprises port switching means for performing switching of opening and closing of the input port and output port in association with movement of the piston. Therefore, when the second cylinder chamber is pressure reduced by movement of the piston, the output port is closed and the input port is opened, and when the second cylinder chamber is pressurized by movement of the piston, the input port is closed and the output port is opened. The port switching means is incorporated preferably in the second cylinder chamber.




In another aspect of the present invention, the second cylinder chamber may have an input port for sucking ink, the piston shaft has a hollow cylindrical form, and the hollow part may be an output port for discharging ink. The cylinder pump unit further comprises port switching means for performing switching of opening and closing of the input port and output port in association with movement of the piston. Therefore, when the second cylinder chamber is pressure reduced by movement of the piston, the output port is closed and the input port is opened, when the second cylinder chamber is pressurized by movement of the piston, the input port is closed and the output port is opened.




In another aspect of the present invention, the port switching means is a check valve provided in a passage communicating with the input port and a check valve provided between the piston and the piston shaft.




In another aspect of the present invention, the piston driving means comprises a screw rod engaging with the piston shaft in the piston shaft and rod driving means for rotatively driving the screw rod.




In another aspect of the present invention, the piston driving means may comprise a pump driving arm for connecting through the piston shaft, a lead screw engaging with the pump driving arm for reciprocally driving the pump driving arm and screw driving means for rotatively driving the lead screw.




In another aspect of the present invention, the first cylinder chamber may be connected with an air suction part provided with a porous film in an ink tank. The air suction part introduces a negative pressure that supplies ink from intake into the ink tank. The piston shaft is a hollow cylindrical body and provided with a relief valve at a tip of the piston shaft for maintaining suction pressure of the first cylinder chamber at less than a predetermined pressure. A setting relief pressure of the relief valve is preferably set smaller than a pressure capable of maintaining performance of the porous film.




In another aspect of the present invention, cross sectional form of the cylinder pump may be elliptical.




In another aspect of the present invention, an ink jet printing apparatus comprises an ink tank, a cap, a cylinder pump and piston driving means. The ink tank has an air suction part provided with a porous film, the air suction part introduces a negative pressure that supplies ink from an intake into the ink tank. The cap caps an ink ejection opening of a recording head capable of ejecting ink supplied from the ink tank. The cylinder pump includes a reciprocally movable piston, a cylinder main body having a first cylinder chamber partitioned at one side of the piston and connected with the air suction part, and a second cylinder chamber partitioned at the other side of the piston and connected with the cap. The piston driving means reciprocally moves the piston of the cylinder pump. Air in the ink tank is sucked through the air suction part of the ink tank by the first cylinder chamber of the cylinder pump, and ink is sucked from the cap by the second cylinder chamber of the cylinder pump.




The above and other objects, effects, features and advantages of the present invention will become more apparent from the following description of embodiments thereof taken in conjunction with the accompanying drawings.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a front elevation view of a printer-built-in camera to which the present invention is applicable;





FIG. 2

is a perspective view of the camera in

FIG. 1

viewing diagonally from the front thereof;





FIG. 3

is a perspective view of the camera in

FIG. 1

viewing diagonally from the back thereof;





FIG. 4

is a perspective view of a medium pack insertable to the camera in

FIG. 1

;





FIG. 5

is a perspective view showing an arrangement of the main components within the camera in

FIG. 1

;





FIG. 6

is a perspective view of a printer section in

FIG. 5

;





FIG. 7

is a perspective view in which a portion of the printer section in

FIG. 6

is dislodged;





FIG. 8

is a perspective view of a carriage of the printer in

FIG. 6

;





FIG. 9

is a perspective view of a component part of a printing medium carrying of the printer section in

FIG. 6

;





FIG. 10

is a perspective view of a component part of the ink supplying of the printer section in

FIG. 6

;





FIG. 11

is a plan view illustrating that the medium pack is inserted into a component part of the ink feeding in

FIG. 10

;





FIG. 12

is a block schematic diagram of the camera section and the printer section of the camera in

FIG. 1

;





FIG. 13

is a schematic diagram of a signal processing performed in the camera section in

FIG. 12

;





FIG. 14

is a schematic diagram of a signal processing performed in the printer section in

FIG. 12

;





FIG. 15

is a diagram showing conceptual construction of an ink supply recovery system;





FIG. 16

is a partially broken perspective view showing a pump unit;





FIG. 17

is a sectional diagram showing stand-by state of a cylinder pump;





FIG. 18

is a partially sectional diagram showing stand-by state of the cylinder pump;





FIG. 19

is a partially sectional diagram showing the cylinder pump when the piston is at an ink supply start position;





FIG. 20

is a partially sectional diagram showing the cylinder pump when the piston is at a valve switching position;





FIG. 21

is a partially sectional diagram showing the cylinder pump when the piston is at an ink supply start position;





FIG. 22

is a perspective diagram showing construction such as a joint lifter and the carriage;





FIG. 23

is a sectional diagram showing stand-by state of a joint and a suction cap;





FIG. 24

is a sectional diagram showing ink supply state of a joint and a suction cap;





FIG. 25

is a sectional diagram showing ink suction state of a joint and a suction cap;





FIG. 26

is a sectional diagram showing empty suction state of a joint and a suction cap;





FIG. 27

is a sectional diagram showing printing state of a joint and a suction cap;





FIG. 28

is a block diagram showing conceptual construction of a control drive system of the ink supply recovery system;





FIG. 29

is a diagram showing an example of operation sequence of the ink supply recovery processing;





FIG. 30

is a diagram showing changes with the passage of time of drive position of a joint lifter, piston and a wiper in a cycle of ink supply recovery processing;





FIG. 31

is a conceptual diagram showing state of each part of the ink supply recovery system before medium pack insertion;





FIG. 32

is a conceptual diagram showing state of each part of the ink supply recovery system during stand-by;





FIG. 33

is a conceptual diagram showing state of each part of the ink supply recovery system before ink supply;





FIG. 34

is a conceptual diagram showing state of each part of the ink supply recovery system during joint connection before ink supply;





FIG. 35

is a conceptual diagram showing state of each part of the ink supply recovery system during ink supply;





FIG. 36

is a conceptual diagram showing state of each part of the ink supply recovery system before ink suction;





FIG. 37

is a conceptual diagram showing state of each part of the ink supply recovery system during ink suction;





FIG. 38

is a conceptual diagram showing state of each part of the ink supply recovery system during empty suction;





FIG. 39

is a conceptual diagram showing state of each part of the ink supply recovery system during printing;





FIG. 40A

is a perspective diagram of the structure of ink supply system in the printer section of

FIG. 6

using another pump unit;





FIG. 40B

is a schematic diagram showing only the pump unit viewed from the arrow A direction in

FIG. 40A

;





FIG. 41

is a cross sectional diagram showing the structure of the pump used in the pump unit of

FIG. 40A

;





FIG. 42

is a diagram for explaining operation by lead screw of the pump unit of

FIG. 40A

;





FIG. 43

is a perspective diagram showing the printer main body for explaining various operations according to positions of the pump drive arm and the switching slider moved by the lead screw of the pump unit;





FIG. 44

is a diagram showing the same state shown in

FIG. 43

shown with another subject matter added;





FIG. 45

is a perspective diagram of the printer main body for explaining various operations according to other positions of the pump drive arm and the switching slider moved by the lead screw of the pump unit;





FIGS. 46A

,


46


B and


46


C are diagrams for explaining the state of an atmosphere communication valve of the suction cap in respective states shown in

FIG. 43

, FIG.


44


and

FIG. 45

; and





FIGS. 47A

,


47


B and


47


C are diagrams for explaining the state of mechanism for operating the atmosphere communication valve of the suction cap in respective states shown in

FIG. 43

, FIG.


44


and FIG.


45


.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




In the following, embodiments of the present invention will be described with reference to the drawings.




In the present specification, “printing” (also referred to as “recording” in some cases) means not only a condition of forming significant information such as characters and drawings, but also a condition of forming images, designs, patterns and the like on printing medium widely or a condition of processing the printing mediums, regardless of significance or unmeaning or of being actualized in such manner that a man can be perceptive through visual perception.




Also, a “printer” and a “recording apparatus” mean not only one complete apparatus for carrying out a printing but also an apparatus having a function for printing.




Further, the “printing medium” means not only a paper used in a conventional printing apparatus but also everything capable of accepting inks, such like fabrics, plastic films, metal plates, glasses, ceramics, wood and leathers, and in the following, will be also represented by a “sheet” or simply by a “paper”.




Further, in the present specification, a “camera” indicates an apparatus or device that optically photographs an image and converts the photographed image into electrical signals, and in the following explanation, is also referred to as a “photographing section”.




Still further, an “ink” (also referred to as “liquid” in some cases) should be interpreted in a broad sense as well as a definition of the above “printing” and thus the ink, by being applied on the printing mediums, shall mean a liquid to be used for forming images, designs, patterns and the like, processing the printing medium or processing inks (for example, coagulation or encapsulation of coloring materials in the inks to be applied to the printing mediums).




Meantime, one embodiment of a head to which the present invention is advantageously employed is the embodiment in which a thermal energy generated by an electrothermal converter is utilized to cause a film boiling to the liquid resulting in a formation of bubbles.




[Basic Structure]




Firstly, a basic structure of a device according to the present invention will be explained in view of

FIGS. 1

to


14


. The device explained in the present embodiments is constituted as an information processing equipment comprising a photographing section for optically photographing an image and then converting the photographed image into an electric signals (hereinafter, also referred to as “camera section”) and an image recording section for recording image on the basis of thus obtained electric signals (hereinafter, also referred to as “printer section”). Hereinafter, the information processing equipment in the present embodiments is explained in the name of a “printer-built-in camera”.




In a main body A


001


, there is incorporated a printer section (recording apparatus section) B


100


at the backside of a camera section A


100


in an integral manner. The printer section B


100


records an image by using inks and printing mediums which are supplied from a medium pack C


100


. In the present structure, as apparent from

FIG. 5

illustrating the main body A


001


viewing from the backside with an outer package removed, the medium pack C


100


is inserted at the right hand of the main body A


001


in FIG.


5


and the printer section B


100


is arranged at the left hand of the main body A


001


in FIG.


5


. In the case of performing a recording by the printer section B


100


, the main body A


001


can be placed facing a liquid crystal display section A


105


up and a lens A


101


down. In this recording position, a recording head B


120


of the printer section B


100


, which will be described below, is made to be positioned to eject inks in the downward direction. The recording position can be made to be the same position as that of photographing condition by the camera section A


100


and thus is not limited to the recording position as mentioned above. However, in view of a stability of a recording operation, the recording position capable of ejecting the inks in the downward direction is preferred.




There follows the explanations of the basic mechanical structure according to the present embodiment under the headings of 1 as “Camera Section”, 2 as “Medium Pack” and 3 as “Printer Section”, and of the basic structure of the signal processing under the heading of 4 as “Signal Processing”.




1: Camera Section




The camera section A


100


, which basically constitutes a conventional digital camera, constitutes the printer-built-in digital camera having an appearance in

FIGS. 1

to


3


by being integrally incorporated into the main body A


001


together with a printer section B


100


described below. In

FIGS. 1

to


3


, A


101


denotes a lens; A


102


denotes a viewfinder; A


102




a


denotes a window of the viewfinder; A


103


denotes a flush; A


104


denotes a shutter release button; and A


105


denotes a liquid crystal display section (outer display section). The camera section A


100


, as described below, performs a processing of data photographed by CCD, a recording of the images to a compact flash memory card (CF card) A


107


, a display of the images and a transmission of various kinds of data with the printer section B


100


. A


109


denotes a discharge part for discharging a printing medium C


104


on which the photographed image is recorded. A


108


, as shown in

FIG. 5

, is a battery as a power source for the camera section A


100


and the printer section B


100


.




2: Medium Pack




A medium pack C


100


is detachable relating to a main body A


001


and, in the present embodiment, is inserted through an inserting section A


002


of the main body A


001


(see FIG.


3


), thereby being placed in the main body A


001


as shown in FIG.


1


. The inserting section A


002


is closed as shown in

FIG. 3

when the medium pack C


100


is not inserted therein, and is opened when the medium pack is inserted therein.

FIG. 5

illustrates a status wherein a cover is removed from the main body A


001


to which the medium pack C


100


is inserted. As shown in

FIG. 4

, a shutter C


102


is provided with a pack body C


101


of the medium pack C


100


in such manner being slidable in an arrow D direction. The shutter C


102


, which slides to stay at a position indicated by the two-dots-and-dushed lines in

FIG. 4

when the medium pack C


100


is not inserted in the main body A


001


, while slides to a position indicated by the solid lines in

FIG. 4

when the medium pack C


100


is placed in the main body A


001


.




The pack body


101


contains ink packs C


103


and printing mediums C


104


. In

FIG. 4

, the ink packs C


103


are held under the printing mediums C


104


. In the case of the present embodiment, three ink packs C


103


are provided so as to separately hold the inks of Y (yellow), M (magenta) and C (cyan), and about twenty sheets of the printing mediums C


104


are stored in pile. A suitable combination of those inks and the printing mediums C


104


for recording an image is selected to be stored within the medium pack C


100


. Accordingly, the various medium packs C


100


each having a different combination of the inks and the printing mediums (for example, medium packs for super high-quality image; for normal image; and for sealing (seal partitioning)) are prepared and, according to a kind of images to be recorded and an use of the printing medium on which an image is formed, those medium packs C


100


are selectively inserted in the main body A


001


, thereby being able to perform an ensured recording of the images in compliance with the purpose by employing the most suitable combination of the ink and the printing medium. Further, the medium pack C


100


is equipped with the below-mentioned EEPROM to which is recorded the identification data such as kinds or remaining amounts of the inks and the printing mediums contained in the medium pack.




The ink pack C


103


, upon the medium pack C


100


is inserted in the main body A


001


, is connected to an ink supplying system in the main body A


001


, through three joints C


105


each corresponding to the respective inks of Y, M and C. On the other hand, the printing mediums C


104


are separated one by one using a separating mechanism which is not shown in the figures and then sent to a direction of an arrow C by a paper feeding roller C


110


(see FIG.


9


). A driving force of the paper feeding roller C


110


is supplied from an after-mentioned conveying motor M


002


(see

FIG. 9

) provided on the main body A


001


through a connecting portion C


110




a.






Further, the pack body C


101


comprises a wiper C


106


for wiping a recording head of the after-mentioned printer section, and an ink absorption body C


107


for absorbing the abolished inks discharged from the printer section. The recording head in the printer section reciprocates in a direction of the main scanning direction as indicated by an arrow A in such manner describing below. When the medium pack C


100


is in the status of being removed from the main body A


001


, the shutter C


102


slides to an position indicated by the two-dots-and-dashed lines in

FIG. 4

to protect the joints C


105


, the wiper C


106


, the ink absorbing body C


107


and so on.




3: Printer Section




The printer section B


100


according to the present embodiment is a serial type employing an ink jet recording head. This printer section B


100


is explained under the headings of 3-1 “Printing Operating Section”; 3-2 “Printing Medium Carrying”; and 3-3 “Ink Supplying System”, respectively.




3-1: Printing Operating Section





FIG. 6

is a perspective view illustrating the entire printer section B


100


, and

FIG. 7

is a perspective view illustrating the printer section B


100


with a part partially taken out.




At a predetermined position in the main body of the printer section B


100


, a tip portion of the medium pack C


100


is positioned when the medium pack C


100


is placed in the main body A


001


as shown in FIG.


5


. The printing medium C


104


sent to the direction of an arrow C from the medium pack C


100


, while being sandwiched between a LF roller B


101


and a LF pinch roller B


102


of the below-mentioned printing medium carrying system, is carried to the sub-scanning direction indicated by an arrow B on a pressure plate B


103


. B


104


denotes a carriage which reciprocates toward a main scanning direction indicated by an arrow A along a guiding shaft B


105


and a leading screw B


106


.




As shown in

FIG. 8

, the carriage B


104


is provided with a bearing B


107


for a guiding shaft B


105


and a bearing B


108


for a leading screw B


106


. At a fixed position of the carriage B


104


, as shown in

FIG. 7

, a screw pin B


109


projecting toward an interior of the bearing B


108


is installed by a spring B


110


. A fit of a tip of the screw pin B


109


to a helical thread formed on the outer circumference of the leading screw


13106


converts a rotation of the leading screw B


106


to a reciprocating movement of the carriage B


104


.




The carriage B


104


is equipped with an ink jet recording head B


120


capable of ejecting the inks of Y, M and C, and a sub-tank (not shown) for reserving inks to be supplied to the recording head B


120


. On the recording head B


120


, a plurality of ink ejection openings B


121


(see FIG.


8


), which are aligned with the direction crossing with the main scanning direction indicated by the arrow A (in the present embodiment, an orthogonal direction), are formed. The ink ejection openings B


121


form nozzles capable of ejecting inks supplied from the sub-tank. As a generating means of energy for discharging the inks, an electro-thermal converting element equipped with each of the nozzles may be used. The electro-thermal converting element generates bubble in the inks within the nozzle by a heating and thus generated foaming energy causes an ejection of the ink droplet from the ink ejection opening B


121


.




The sub-tank has a capacity smaller than the ink packs C


103


contained in the media pack C


100


and made to be a sufficient size for storing a required amount of ink for recording an image corresponding to at least one sheet of printing medium C


104


. In the sub-tank, there are ink reserving sections for each of the inks of Y, M and C, on each of which is formed the ink supplying section and the negative pressure introducing sections, wherein those ink supplying sections are individually connected to the corresponding three hollow needles B


122


and those negative pressure introducing sections are also connected to a common air suction opening B


123


. Such ink supplying sections, as will be mentioned below, are supplied with inks from the ink packs C


103


in the medium pack C


100


when the carriage B


104


moves to a home position as illustrated in FIG.


6


.




In the carriage B


104


in

FIG. 8

, B


124


denotes a needle cover which is moved to a position for protecting the needles B


122


by the force of the springs as illustrated in

FIG. 8

when the needles B


122


and the joints C


105


are not mated each other, and which releases a protection of the needles B


122


by being pushed upwardly against the force of the springs in

FIG. 8

when the needles B


122


and the joints C


105


are mated with each other. A movement position of the carriage B


104


is detected by an encoder sensor B


131


on the carriage B


104


and a linear scale B


132


(see

FIG. 6

) on the main body of the printer section B


100


. Also, a fact that the carriage B


104


moves to the home position is detected by a HP (home position) flag B


133


on the carriage B


104


and a HP sensor B


134


(see

FIG. 7

) on the main body of the printer section B


100


.




In

FIG. 7

, at the both ends of the guiding shaft B


105


, supporting shafts (not shown) are provided at a position eccentric to the center axis of the guiding shaft. The guiding shaft B


105


is turned and adjusted upon the supporting shaft, thereby controlling a height of the carriage


104


, resulting in achieving an adjustment of a distance between the recording head B


120


and the printing medium C


104


on the pressure plate B


103


. The leading screw B


106


is rotatably driven by a carriage motor M


001


through a screw gear B


141


, an idler gear B


142


and a motor gear B


143


. B


150


denotes a flexible cable for electrically connecting the after-mentioned controlling with the recording head B


120


.




The recording head B


120


moves together with the carriage B


104


toward the main scanning direction indicated by the arrow A and concurrently ejects the inks from the ink ejection openings B


121


in accordance with the image signals, thereby recording an image corresponding to one band on the printing medium on the pressure plate B


103


. An alternate repeat of a recording operation of an image corresponding to one band by such recording head B


120


and a conveying operation of the predetermined amount of the printing medium toward the sub-scanning direction indicated by the arrow B by means of the below-mentioned printing medium conveying system enables a sequential recording of the images on the printing medium.




3-2: Printing Medium Carrying





FIG. 9

is a perspective view showing a component of the printing medium conveying system of the printer section B


100


. In

FIG. 9

, B


201


denotes a pair of paper delivering rollers, and the upper one of the paper delivering rollers B


201


in

FIG. 9

is driven by a conveying motor M


002


through the paper delivering roller gear B


202


and a junction gear B


203


. Likewise, the aforementioned LF roller B


101


is driven by the conveying motor M


002


through a LF roller gear B


204


and the junction gear B


203


. The paper delivering roller B


201


and the LF roller B


101


convey the printing medium C


104


toward the sub-scanning direction indicated by the arrow B by a driving force of the conveying motor M


002


rotating in the forward direction.




On the other hand, when the conveying motor M


002


couterrotates, a pressure plate head B


213


and a locking mechanism which is not shown are driven through a switching slider B


211


and a switching cam B


212


, while a driven force is transmitted to the paper feeding roller C


110


on the medium pack C


100


. That is, the pressure plate head B


213


pressurizes the printing mediums C


104


, which are piled up within the medium pack C


100


, in a downward direction in

FIG. 4

by a driven force caused by a reverse rotation of the carrying motor M


002


, through a window portion C


102


A (see

FIG. 4

) of a shutter C


102


of the medium pack C


100


. As a result thereof, the printing medium C


104


positioned at the lowest position in

FIG. 4

is pressed against the feeding roller C


110


in the medium pack C


100


. Also, the locking mechanism which is not shown locks the medium pack C


100


to the main body A


001


to inhibit a removal of the medium pack C


100


. The feeding roller C


110


of the medium pack C


100


feeds one piece of the printing medium C


104


at the lowest position in

FIG. 4

toward the direction indicated by the arrow C as a result that the driven force caused by the reverse rotation of the conveying motor M


002


is transmitted.




As stated above, only one piece of printing medium C


104


is taken out from the medium pack C


100


toward the direction indicated by the arrow C by the reverse rotation of the conveying motor M


002


, and then a forward rotation of the conveying motor M


002


conveys the printing medium C


104


to the direction indicated by the arrow B.




3-3: Ink Supplying System





FIG. 10

is a perspective view showing a component part of an ink supplying system of the printer section B


100


:

FIG. 11

is a plane view showing a status that the medium pack C


100


is inserted in the component part of the ink supplying system.




A joint C


105


of the medium pack C


100


installed to the printer section B


100


is positioned below the needles B


122


(see

FIG. 8

) on the carriage B


104


moved to a home position. The main body of the printer section B


100


is equipped with a joint fork B


301


(see

FIG. 10

) positioned below a joint C


105


, and an upward movement of the joint C


105


caused by the joint fork B


301


establishes a connection of the joint C


105


to the needles B


122


. As a result thereof, an ink supplying path is formed between the ink packs C


103


in the medium pack C


100


and the ink supplying sections on the sub-tank on the carriage B


104


. Further, the main body of the printer section B


100


is equipped with a suction joint B


302


positioned below an air suction opening B


123


(see

FIG. 8

) of the carriage B


104


moved to the home position. This suction joint B


302


is connected to a pump cylinder B


304


of a pump serving as a negative pressure generating source, through a suction tube B


304


. The suction joint B


302


is connected to the air suction opening B


123


on the carriage B


104


according to the upward movement caused by a joint lifter B


305


. In the light of the foregoing, a negative pressure introducing path, between a negative pressure introducing section of the sub-tank on the carriage B


104


and the pump cylinder B


304


, is formed. The joint lifter B


305


makes the joint fork B


301


move up and down together with the suction joint B


302


by a driving power of the joint motor M


003


.




The negative pressure introducing section of the sub-tank is equipped with a gas-liquid partition member (not shown) which allows a passing through of air but prevents a passing through of the inks. The gas-liquid partition member allows a passing through of the air in the sub-tank to be suctioned through the negative pressure introducing path, and as a result, an ink is supplied to the sub-tank from the medium pack C


100


. Then, when the ink is sufficiently supplied to the extent that the ink in the sub-tank reaches to the gas-liquid partitioning member, the gas-liquid partitioning member prevents the passing through of the inks, thereby automatically stopping a supply of the inks. The gas-liquid partitioning member is equipped with the ink supplying section in the ink storing sections for the respective inks in the sub-tank, and thus the ink supplying is automatically stopped with respect to each ink storing section.




The main body of the printer section B


100


is further equipped with a suction cap B


310


capable of capping with respect to the recording head B


120


(see

FIG. 8

) on the carriage B


104


which moved to the home position. The suction cap B


310


is introduced the negative pressure thereinto from the pump cylinder B


304


through suction tube B


311


, so that the inks can be suctioned and emitted (suction recovery processing) from the ink ejection openings B


121


of the recording head B


120


. Further, the recording head B


120


, as required, makes the ink, which does not contribute to a recording-of an image, ejection into the suction cap B


310


(preliminary ejection processing). The ink within the suction cap B


310


is discharged into the ink absorption body C


107


in the medium pack C


110


from the pump cylinder B


304


through a waste water liquid tube B


312


and a waste liquid joint B


313


.




The pump cylinder B


304


constitutes a pump unit B


315


together with a pump motor M


004


for enabling a reciprocate drive of the pump cylinder. The pump motor M


004


also functions as a driving source by which a wiper lifter B


316


(see

FIG. 10

) is moved up and down. The wiper lifter B


316


makes the wiper C


106


of the medium pack C


100


placed in the printer section B


100


move upwardly, thereby displacing the wiper C


106


to a position capable of a wiping of the recording head B


120


.




In

FIGS. 10 and 11

, B


321


denotes a pump HP sensor for detecting if an operating position of the pump, which is constituted by the pump cylinder B


304


, lies at the home position. Further, B


322


denotes a joint HP sensor for detecting if the aforementioned ink supplying path and the negative pressure introducing path were formed. Still further, B


323


denotes a chassis for constituting a main body of the printer section B


100


.




4: Signal Processing





FIG. 12

is a block diagram generally showing the camera section A


100


and the printer section B


100


.




In the camera section A


100


,


101


denotes a CCD as an image element;


102


denotes a microphone for inputting voice;


103


denotes an ASIC (Application Specific IC) for performing various processings;


104


denotes a first memory for temporary storing an image date and the like;


105


denotes a CF (compact flush) card (corresponding to a “CF card A


107


”) for recording the photographed image;


106


denotes a LCD (corresponding to a “liquid crystal display section A


105


”) which displays the photographed image or a replayed image; and


120


denotes a first CPU for controlling the camera section A


100


.




In the printer section B


100


,


210


denotes an interface between the camera section A


100


and the printer section B


100


;


201


denotes an image processing section (including a binary processing section for binarizing an image);


202


denotes a second memory to be used in performing the image processing;


203


denotes a band memory controlling section;


204


denotes a band memory;


205


denotes a mask memory;


206


denotes a head controlling section;


207


denotes a recording head (corresponding to the “recording head B


120


”);


208


denotes an encoder (corresponding to the “encoder sensor B


131


”);


209


denotes an encoder counter;


220


denotes a second CPU for controlling the printer section B


100


;


221


denotes motor drivers;


222


denotes motors (corresponding to the motors M


001


, M


002


, M


003


and M


004


″);


223


denotes sensors (including the “HP sensors B


134


, B


321


and B


322


”);


224


denotes an EEPROM contained in the medium pack C


100


;


230


denotes a voice encoder section and


250


denotes a power source section for supplying electric power to the entire device (corresponding to the “battery A


108


”).





FIG. 13

is a schematic diagram showing a signal processing in the camera section A


100


. In a photographing mode, an image photographed by the CCD


101


through a lens


107


is signal-processed (CCD signal processing) by ASIC


103


and then is converted to YUV intensity with two-color-different signal. Further, the photographed image is resized to a predetermined resolution and recorded on a CF card


105


using a compression method by JPEG, for example. Also, a voice is inputted through a microphone


102


and stored in the CF card


105


through the ASIC


103


. A recording of the voice can be performed in such manner recording at the same time of photographing, or after photographing so called an after-recording. In a replay mode, the JPEG image is read out from the CF card


105


, extended by the JPEG through the ASIC


103


and further resized to be a resolution for displaying, thereby being displayed on the LCD


106


.





FIG. 14

is a schematic diagram showing a signal processing performed in the printer section B


100


.




An image replayed on the camera section A


100


, that is the image being read out from the CF card


105


, is extended by the JPEG as shown in

FIG. 13

to resize a resolution to a suitable size for printing. Then, the resized image data (YUV signal), through an interface section


210


, is transferred to the printer section B


100


. As shown in FIG.


14


, the printer section B


100


performs an image processing of an image data transferred from the camera section A


100


by an image processing section


201


, thereby performing an conversion of the image data to a RGB signal, an input γ correction in accordance with the features of a camera, a color correction and a color conversion using a look up table (LUT), and an conversion to a binarized signal for printing. When performing the binarizing processing, in order to perform an error diffusion (ED), a second memory


202


is utilized as an error memory. In the case of the present embodiment, though a binarizing processing section in the image processing section


201


performs the error diffusion processing, in other processing may be performed such as a binarizing processing using a dither pattern. The binarized printing data is stored temporary in the band memory


204


by a band memory controlling section


203


. An encoder pulse from the encoder


208


enters into the encoder counter


209


of the printer section B


100


every time the carriage B


104


carrying the recording head


207


and the encoder


208


moves a certain distance. Then, in sync with this encoder pulse, a printing data is read out from the band memory


204


and the mask memory


205


, and, based on thus obtained printing data, the head controlling section


206


controls the recording head


207


to perform a recording.




A band memory shown in

FIG. 14

is explained as below.




A plurality of nozzles in the recording head


207


, for example, is formed in array so as to achieve a density of 1200 dpi (dots/inch). For recording the image by using such recording head


207


, upon performing one scanning by the carriage, it is preferred to previously prepare a recording data (a recording data corresponding to one scanning) corresponding to the number of nozzles in the sub-scanning direction (hereinafter, also referred to as a “column (Y direction)”) and a recording data corresponding to the recording area in the scanning direction (hereinafter, also referred to as a “row (X direction)”, respectively. The recording data is created in the image processing section


201


and then is temporary stored in the band memory


204


by the band memory controlling section


203


. After the recording data corresponding to one scan is stored in the band memory


204


, the carriage is scanned in the main scanning direction. In so doing, an encoder pulse inputted by the encoder


208


is counted by the encoder counter


209


and, in accordance with this encoder pulse, a recording data is read out from the band memory


204


. Then, on the basis of the image data, ink droplets are ejected from the recording head


207


. In the case that a bidirectional recording system wherein an image is recorded upon outward scanning and homeward scanning (outward recording and homeward recording) of the recording head


207


is employed, the image data is read out from the band memory


204


depending on the scanning direction of the recording head


207


. For example, an address of the image data read out from the band memory


204


is increased sequentially when the outward recording is performed, while an address read out from the band memory


204


is decreased sequentially when the homeward scanning is performed.




In a practical sense, a writing of an image data (C, M and Y) created by the image processing section


201


into the band memory


204


and a subsequent preparation of the image data corresponding to one band enable a scanning of the recording head


207


. Then, the image data is read out from the band memory


204


subsequent to a scan of the recording head


207


, so that the recording head


207


records the image on the basis of the image data. While the recording operation, an image data to be recorded next is created at the image processing section


201


and thus created image data is written into an area of the band memory


204


corresponding to a recording position.




As has been stated above, the band memory controlling is carried out in such manner that a writing operation in which an recording data (C, M, Y) created by the image processing section


201


is written into the band memory


204


and a reading operation for transferring the recording data (C, M, Y) to the head controlling section


206


in accordance with a scanning movement of the carriage are changed over.




A mask memory controlling in

FIG. 14

is explained as below.




This mask memory controlling is required when a multipass recording system is employed. In using the multipass recording system, the recording image corresponding to one line which has a width corresponding to a length of the nozzle array of the recording head


207


is divided to a plurality of scanning of the recording head


207


to record. That is, conveying amount of the printing medium to be intermittently carried to the sub-scanning direction is made to be 1/N of a length of the nozzle array. For example, when N=2, a recording image corresponding to one line is divided into two scans to record (two-pass recording), and when N=4, a recording image corresponding to one line is divided into four scans to record (four-pass recording). In similar fashion, when N=8, it becomes eight-pass recording, and when N=16, it becomes sixteen-pass recording. Therefor, the recording image corresponding to one line will be completed by a plurality of scans of the recording head


207


.




Practically, a mask data for assigning the image data to a plurality of scans of the recording head


207


is stored in the mask memory


205


, and then based on a conjunction (AND) data between the mask data and the image data, the recording head


207


ejects inks to record the image.




Also, in

FIG. 14

, a voice data stored in the CF card


105


, alike the image data, is transferred to the printer section B


100


through an interface


210


by the ASIC


102


. The voice data transferred to the printer section B


100


is encoded at the voice encoder


230


and then recorded with the image to be printed as a code data. When there is no necessity to input a voice data into a printing image, or when printing an image without a voice data, of course, the encoded voice data is not printed but only the image is printed.




In the present embodiment, the present invention has been explained as a printer built-in camera integral with a camera section A


100


and printer section B


100


. However, it would be possible to make each of the camera section A


100


and the printer section B


100


a separate device and to form in a similar manner as a structure in which those devices are connected each other by the interface


210


to realize a similar function.




[Characteristic Construction]




(First Embodiment)




In the following, a first embodiment of characteristic construction of the present invention will be described.




(Ink Supply Recovery System)





FIG. 15

shows conceptual construction of the ink supply recovery system.




In

FIG. 15

, in a medium pack C


100


, three ink packs (or main tank) C


103


charged with three color inks of Y (yellow), M (magenta), and C (cyan) are contained. These three ink packs C


103


are connected to three joints C


105


through three ink supply passages C


200


.




The medium pack C


100


is provided with a waste liquid introducing hole C


120


(see

FIG. 4

) which is inserted and connected with a waste liquid joint B


313


(see

FIG. 10

) provided at the tip of a waste liquid tube B


312


on the printer section B


100


. The medium pack C


100


is provided with a waste ink absorption body C


107


for storing waste ink flowing from a cylinder pump B


410


through the waste liquid introducing hole C


120


.




The carriage B


104


is equipped with sub-tanks (or carriage tanks) B


400


separately storing Y, M, and C inks, and a recording head B


120


having a plurality of ink ejection openings (nozzles) for three groups (Y, M and C) for ejecting inks supplied from the respective carriage tanks B


400


.




The respective ink reserving section (ink supplying section) of the sub-tank B


400


are nearly almost fully charged with an ink absorption body (for example, sponge) B


401


for absorbing and holding inks such as made of polypropylene fiber or the like. Further, the respective ink reserving section (ink supplying section) of the sub-tanks B


400


, as shown in

FIG. 8

, are provided with hollow needles B


122


as an ink intake protruding downward. These three needles B


122


become connectable with three rubber joints C


105


of the medium pack C


100


when the carriage B


104


moves to the home position.




Above the respective ink suppliers of the sub-tanks B


400


, negative pressure introducing section (air suction part) B


406


are formed. These negative pressure introducing section B


406


are, as described above, finished to be water repellent and oil repellent, and respectively provided with porous films (ink filling valves) B


402


as gas-liquid partition members which allow a passing through of air but prevent a passing through of the ink. Since passage of ink is blocked with this porous film B


402


, ink supply is stopped automatically when the ink surface in the sub-tanks reaches the porous film B


402


.




The respective negative pressure introducing section B


406


of the sub-tanks B


400


are, as described above, communicated with a common air suction opening B


123


(

FIG. 8

) formed on the lower surface side of the carriage B


104


. The air suction opening B


123


, when the carriage B


104


moves to the home position, becomes connectable with a suction joint B


302


provided on the main body of the printer section B


100


, and connectable with one cylinder chamber of the cylinder pump B


410


of the pump unit B


315


through the suction joint B


302


and the suction tube B


303


.




On the printer section B


100


, there is provided a suction cap B


310


for capping the face (ink ejection opening formation surface) B


403


of the recording head B


120


on which a plurality of ink ejection openings (nozzles) B


121


for three groups of Y, M, C are formed when the carriage B


104


moves to the home position. The suction cap B


310


is provided with an air communication opening B


404


. The air communication opening B


404


can be opened and closed by an air communication valve B


405


.




The suction cap B


310


is connected to the other cylinder chamber of the cylinder pump B


410


through the suction tube B


311


.




A cylinder main body (a pump cylinder) B


304


has three ports connected with the suction tube B


303


, the suction tube B


311


and the waste liquid tube B


312


.




(Pump Unit)




A pump unit B


315


including the cylinder pump B


410


will be described in detail with reference to

FIGS. 16

to


21


.




As shown in these drawings, the cylinder pump B


410


has a cylinder main body B


304


and a piston B


411


. The piston B


411


has a piston shaft B


411




a


and a piston body (hereinafter referred to as piston rubber) B


412


comprising an elastic material such as rubber provided at a tip flange of the piston shaft B


411




a.






The cylinder main body B


304


is partitioned by the piston rubber B


412


into two (right and left) pump chambers (an air suction chamber B


413


and an ink suction chamber B


414


).




The air suction chamber B


413


is introduced with air (the first fluid), and the ink suction chamber B


414


is supplied with ink (the second fluid). The air suction chamber B


413


is provided with an input/output port B


415


communicated with the suction tube B


303


. The ink suction chamber B


414


is provided with an input port B


416


communicated with the suction tube B


311


and an output port B


417


communicated with the waste liquid tube B


312


. On an end surface wall B


425


of the ink suction chamber B


414


, there are formed a hole B


426


(

FIG. 17

) for inserting and sliding with the piston shaft B


411




a


and a hole B


427


(

FIG. 18

) for inserting and sliding with a plurality of slide pins B


442


which will be described later.




The piston B


411


, as shown in FIG.


16


and

FIG. 17

, has a penetrated hollow cylindrical form and can be introduced with the atmosphere into the hollow part B


418


. The tip flange part B


419


of the piston


411


is provided with a relief valve B


420


which operates when the suction pressure (negative pressure) of the air suction chamber B


413


exceeds a predetermined pressure.




The relief valve B


420


comprises a valve main body B


421


and a spring B


422


for setting the relief pressure. The spring B


422


is interposed between a spring stopper B


421


of the valve main body B


421


and the flange part B


419


so that the valve main body B


421


is released with a predetermined relief pressure.




As described above, when the suction pressure (negative pressure) of the air suction chamber B


413


exceeds a predetermined pressure, since the relief valve B


420


is opened so that air is little by little sucked into the air suction chamber B


413


, negative pressure greater than the relief pressure is all cut off. The relief pressure of the relief valve B


420


is set so that the pressure is less than a pressure that is able to maintain the performance of the porous film B


402


.




In the pit-in ink supply method using the porous film B


402


in the sub-tank B


400


, ink supplying to the sub-tank B


400


is performed by sucking air in the tank B


402


with the cylinder pump B


410


through the porous film B


402


. When suction is performed by the cylinder pump B


410


with the ink tank is fully charged state, ink leakage from the porous film B


402


is prevented by the function of the porous film B


402


, however, it has an adverse effect on the durability of the porous film B


402


, reducing the service life of the porous film B


402


. Then, in this system, the relief value B


420


is disposed in the piston shaft B


411




a


of the cylinder pump B


410


for achieving space-saving and preventing exertion of an excessive ink pressure to the porous film B


402


during ink supply, thereby assuring reliable operation of the porous film B


402


.




In the hollow part B


418


of the piston shaft B


411




a


, a screw rod (pump unit) B


460


is inserted in a screwed state, so that by the rotation of the screw rod B


460


, the piston B


411


is reciprocally moved in the piston shaft direction. The screw rod B


460


is, as shown in

FIG. 16

, connected to a pump motor M


004


as a drive source through a gear mechanism B


430


, and rotated by the rotation of the pump motor M


004


.




At the rear end side of the piston B


411


, as shown in FIG.


18


and the like, a pressure slider B


431


is disposed. The pressure slider B


431


is also screwed with the screw rod B


460


, and can be reciprocally moved in the piston shaft direction in association with the rotation of the screw rod B


460


.




In the ink suction chamber B


414


of the cylinder main body B


304


, a switching valve (hereinafter referred to as valve rubber) B


440


as port switching means comprising an elastic material such as rubber is disposed movably in the piston shaft direction. The valve rubber B


440


is provided with a hole B


441


(

FIG. 17

) for inserting the piston shaft B


411




a


. Therefore, the piston shaft B


411




a


can be freely moved relative to the valve rubber B


440


through the hole


441


. By switching the position of the valve rubber B


440


, one of input port B


416


connecting to the suction tube B


311


and output port B


417


connecting to the waste liquid tube B


312


is opened and the other is closed, thereby controlling open/close state of these input port B


416


and output port B


417


.




Between the rear end surface of the valve rubber B


440


and the pressure slider B


431


, as shown in FIG.


18


and the like, a plurality of slide pins B


442


for pressing the rear end surface of the valve rubber B


440


are disposed. At the (tip side) valve rubber B


440


side of the slide pin B


442


, a pressing body B


433


having a large contact surface is fixed for achieving uniform pressing force to the rear end surface of the valve rubber B


440


.




To obtain a state that the valve rubber B


440


in stand-by state as shown in

FIG. 18

is moved in the piston travel direction (left direction in the figure), so that the input port B


416


is closed and the output port B


417


is opened as shown in

FIG. 19

, the pressing force of the pressure slider B


431


is used.




That is, in stand-by state, the pressure slider B


431


is, as shown in

FIG. 18

, in contact with a plurality of slide pins B


442


. In this state, when the pressure slider B


431


is further moved in the piston travel direction (left direction) by the rotation of the screw rod B


460


, the plurality of slide pins B


442


and the valve rubber B


440


are moved to the left direction to the position shown in

FIG. 19

by the pressing force of the pressure slider B


431


.




On the other hand, to move the valve rubber B


440


from the position shown in

FIG. 19

to the position shown in FIG.


20


and further to the position shown in

FIG. 21

in a piston retreat direction (right direction in the figure), the pressing force of the flange part B


419


at the tip of the piston B


411


is used.




That is, for example, as shown in

FIG. 20

, after the tip flange part B


419


of the piston B


411


is contacted with the valve rubber B


440


, when the piston B


411


is moved in the retreat direction, the valve rubber B


440


and the plurality of slide pins B


442


are moved by the pressing force of the flange part B


419


in the right direction to the position shown in FIG.


21


.




Such position switching of the valve rubber B


440


is performed at a predetermined timing in one cycle including air suction (ink supply), ink suction, and ink discharge by reciprocal movement of the piston B


411


.




Next, air suction, ink suction, and ink discharge operation by the cylinder pump B


410


will be briefly described.




(Air Suction and Ink Discharge Operation)




The state shown in

FIG. 19

is the initial state of air suction, in which the piston B


411


is moved forward almost to the stroke end at the piston travel side. At this moment, the valve rubber B


440


is switched to the position where the ink suction chamber B


414


is communicated with the waste tube B


312


and blocked from the suction tube B


311


.




When, from the state shown in

FIG. 19

, the piston B


411


is moved to the right direction in the piston retreat direction, the air suction chamber B


413


is pressure reduced and the ink suction chamber B


414


is pressurized.




By this operation, air in the sub-tank B


400


is sucked to the air suction chamber B


413


through the porous film B


402


, the negative pressure introducing section B


406


, the air suction opening B


123


, the suction joint B


302


, and the suction tube B


303


(FIG.


15


). As a result, ink is supplied from the main tank C


103


of the medium pack C


100


to the sub-tank B


400


.




On the other hand, it is assumed that the ink suction chamber B


414


is stored with sucked ink from the suction cap B


310


sucked in the previous cycle. In this state, when the piston B


411


is moved from the state shown in

FIG. 19

in right direction in the piston retreat direction, the ink suction chamber B


414


is pressurized. Thus, the sucked ink stored in the ink suction chamber B


414


is flowed through the waste liquid tube B


312


to the waste ink absorption body C


107


of the medium pack C


100


, where it is absorbed and held by the waste ink absorption body C


107


.




(Ink Suction Operation)




The state shown in

FIG. 21

is the initial state of ink suction, in which the piston B


411


is moved almost to the stroke end at the piston retreat side. At this time, the valve rubber B


440


is switched to the position where the ink suction chamber B


414


is communicated with the suction tube B


311


and blocked from the waste liquid tube B


312


.




When, from the state shown in

FIG. 21

, the piston B


411


is moved to the left direction in the piston travel direction, the air suction chamber B


413


is pressurized and the ink suction chamber B


414


is pressure reduced.




By this operation, as shown in

FIG. 15

, the inside of the suction cap B


310


connected to the ink suction chamber B


414


through the suction tube B


311


is evacuated, and ink is sucked from the ink ejection opening B


121


of the recording head B


120


to the suction cap B


310


. The sucked ink is flowed to the ink suction chamber B


414


.




On the other hand, during the ink suction operation, the air suction chamber B


413


is pressurized, however, at this time, as will be described later, since the suction joint B


302


is disconnected from the air suction opening B


123


of the sub-tank B


400


, the inside of the sub-tank B


400


will never be pressurized.




In the cylinder pump B


410


, the cylinder chamber B


414


inserting the piston shaft B


411




a


is used for ink suction and the other cylinder chamber B


413


for air suction. Therefore, suction amounts of the respective cylinder chambers B


413


and B


414


can be set to different values with the same piston stroke. That is, the cylinder chamber B


414


inserting the piston shaft B


411




a


is smaller in suction amount. Further, by changing the shaft diameter of the piston shaft B


411




a


, the suction volume ratio of the ink suction chamber B


414


and the air suction chamber B


413


can be easily changed.




Next, moving mechanism of wiper C


106


of the medium pack C


100


will be described.




As shown in FIG.


16


and

FIGS. 18

to


21


, a plate cam member B


450


for moving up and down a wiper lifter B


316


(see

FIG. 10

) is provided in the vicinity of the cylinder pump B


410


. The plate cam member B


450


, as shown in

FIG. 16

, has a two-stage cam part B


451


differing in height, which moves up and down the wiper lifter B


316


engaging with the cam part B


451


.




The plate cam member


450


is reciprocally movable in the retreat direction of the piston B


411


of the cylinder pump B


410


. The plate cam member


450


has a contact B


452


(

FIG. 18

) contacting with the pressure slider B


431


screwed with the screw rod B


460


. The plate cam member


450


is moved in the forward direction (left direction) of the piston B


411


by being pressed by the movement of the pressure slider B


431


. The plate cam member


450


is moved in the retreat direction (right direction) of the piston B


411


by the righting force of the spring B


453


(

FIGS. 10

,


11


,


18


).




(Joint Lifter Moving Mechanism)




Next, using

FIGS. 22

to


27


, contact/separate mechanism of the joint C


105


of the medium pack C


100


to the needle B


122


of the sub-tank B


400


, contact/separate mechanism of the suction joint B


302


to the air suction opening B


123


of the carriage B


104


, contact/separate mechanism of the suction cap B


310


to the face B


403


of the recording head B


120


, and open/close mechanism of the atmosphere communication opening B


404


of the suction cap by the atmosphere communication valve B


405


will be described in further detail.





FIG. 23

shows stand-by state,

FIG. 24

ink supplying state,

FIG. 25

ink suction state,

FIG. 26

empty suction state, and

FIG. 27

printing state.




The joint motor M


003


rotates and drives the screw rod B


306


through an appropriate gear mechanism (not shown). The screw rod B


306


is screwed with a joint slider B


307


, and therefore the joint slider B


307


is reciprocally moved according to the rotation of the screw rod B


306


. The joint slider B


307


is connected integrally with the joint lifter B


305


.




The joint lifter B


305


is fixed with a joint fork B


301


. Therefore, the joint fork B


301


can be moved up and down according to up/down movement of the joint lifter B


305


. When the medium pack C


100


is attached to the printer section B


100


, the joint C


105


of the medium pack C


100


is supported by the joint fork B


301


. Therefore, the joint C


105


of the medium pack C


100


is also moved up and down according to up/down movement of the joint fork B


301


. When the joint fork B


301


reaches almost the upper side stroke end, as shown in

FIG. 24

, the needle B


122


of the sub-tank B


400


completely penetrates the sealing body (joint rubber) C


108


of the joint C


105


, so that an ink supply passage is formed from the main tank C


103


of the medium pack C


100


to the sub-tank B


400


on the carriage B


104


.




On the upper surface of the joint lifter B


305


, the suction joint B


302


connected to the suction tube B


303


for air suction of the cylinder pump B


410


is provided. Therefore, the suction joint B


302


can also be moved up and down according to up/down movement of the joint lifter B


305


. When the suction joint B


302


is lifted to above the predetermined position, the suction joint B


302


is connected with the air suction opening B


123


, thereby forming an air suction passage between the cylinder pump B


410


and the sub-tank B


400


.




The joint lifter B


305


is connected with the suction cap B


310


and the atmosphere communication valve B


405


through an appropriate mechanism. These suction cap B


310


and the atmosphere communication valve B


405


are moved up and down at respective timing during up/down movement of the joint lifter B


305


.




(Control Drive System)





FIG. 28

is a conceptual block diagram showing a brief construction of the control and drive system related to ink supply recovery processing.




A pump HP sensor B


321


detects that the piston B


411


of the cylinder pump B


410


is positioned at stand-by position (home position). A joint HP sensor B


322


detects that the joint lifter B


305


is positioned at the home position. A carriage HP sensor B


134


detects that the carriage B


104


is positioned at the home position. Detection signals of these sensors B


321


, B


322


and B


134


are inputted to a CPU


220


.




The CPU


220


drive controls the joint motor B


305


, the pump motor M


004


, the carriage motor M


001


and the conveying motor M


002


through a joint motor driver


221




a


, a pump motor driver


221




b


, a carriage motor driver


221




c


, and a conveying motor driver


221




d.






The joint motor M


003


is a driving source of up/down movement of the joint lifter B


305


. During up/down movement of the joint lifter B


305


, the suction joint B


302


, the joint fork B


301


, the suction cap B


310


and the atmosphere communication valve B


405


are move up and down at respective predetermined timings.




The pump motor M


004


is a driving source of the screw rod B


460


. The piston B


411


of the cylinder pump B


410


and the pressure slider B


431


are reciprocally moved by the rotation of the screw rod B


460


. Further, by the movement of the pressure slider B


431


, a switching of the valve rubber B


440


is performed, and up/down movement of the wiper C


106


is performed through the plate cam member B


450


and the wiper lifter B


316


.




(Operation Sequence)





FIG. 29

shows an example of operation sequence of ink supply recovery processing, and

FIG. 30

shows drive positions of the joint lifter B


305


and the piston B


411


of the cylinder pump B


410


and the wiper lifter B


316


in one cycle of ink supply recovery processing. Further,

FIGS. 31

to


39


are process diagrams for explaining movements of respective components in the ink supply recovery processing cycle.




In the following, operation sequence of the ink supply recovery processing cycle will be described using

FIGS. 31

to


39


and the like.




(Before Medium Pack Attachment)




When the medium pack C


100


is not attached to the apparatus main body A


001


, as shown in

FIG. 31

, the suction cap B


310


caps the face B


403


of the recording head B


120


, thereby preventing the ink in the ink ejection opening B


121


from drying. Further, at this moment, the suction joint B


302


is at a position away from the air suction opening B


123


of the sub-tank B


400


, and the atmosphere communication opening B


404


of the suction cap B


310


is opened.




(Medium Pack Attachment and Stand-by)




When the medium pack C


100


is completely attached to the apparatus main body A


001


, the joint C


105


of the medium pack C


100


is supported by the joint fork B


301


. At this moment, three joint rubbers C


108


of the joint C


105


are, as shown in FIG.


32


and

FIG. 23

, positioned right beneath the three needles B


122


of the sub-tank B


400


. The suction joint B


302


is positioned right beneath the air suction opening B


123


of the carriage B


104


.




Further, the piston B


411


of the cylinder pump B


410


is positioned at the stand-by position (home position) shown in

FIGS. 16

to


18


, and the joint lifter is also positioned at the home position (

FIG. 29

, step S


1


). Further, the carriage B


104


is also positioned at the home position.




(Carriage Initialization Processing)




When, in this state, a print instruction is outputted, the joint motor M


003


is forward rotated and the joint lifter B


305


is slightly moved down, which also slightly moves down the suction cap B


310


. As a result, the suction cap B


310


is slightly separated from the face B


403


of the recording head B


120


, and the suction cap B


310


is once opened (

FIG. 29

, step S


2


). Further, almost simultaneously with this, initialization of the carriage B


104


is performed (

FIG. 29

, step S


3


).




(Joint Processing)




Next, the pump motor M


004


is forward rotated by a predetermined number of pulses to rotate the screw rod B


460


, whereby the piston B


411


of the cylinder pump B


410


is slightly traveled from the position shown in

FIG. 18

to the ink supply position shown in

FIG. 19

(

FIG. 29

, step S


4


). Further, by the rotation of the screw rod B


460


at this moment, the pressure slider B


431


presses the valve rubber B


440


through the slide pin B


442


, as a result thereof, the valve rubber B


440


, as shown in

FIG. 19

, is moved to a position to close the suction tube B


311


. Therefore, the ink suction chamber B


414


of the cylinder pump B


410


is communicated with the waste ink absorption body C


107


of the medium pack C


100


through the waste liquid tube B


312


.




By the movement of the pressure slider B


431


at this moment, the plate cam member B


450


is moved to the piston travel direction, the wiper lifter B


316


is moved up by the function of the cam part B


451


of the plate cam member B


450


, and the wiper C


106


of the medium pack C


100


is moved up for a small period of time. However, the upward movement of the wiper C


106


has no effects on the movement of other components.




On the other hand, the joint motor M


003


is reverse rotated so that the joint lifter B


305


starts upward movement. When the joint lifter B


305


is moved up by a predetermined amount, the joint HP sensor B


322


detects that the joint lifter B


305


is out of the home position (

FIG. 29

, step S


5


). Further, by upward movement of the joint lifter B


305


, the suction cap B


310


again caps the face B


403


of the recording head B


120


. When the drive position of the joint lifter takes a positive value in FIG.


29


and

FIG. 30

, the suction cap B


310


is capping the face B


403


of the recording head B


120


, and when the drive position takes a negative value, the suction cap B


310


is separated from the face B


403


of the recording head B


120


.




During upward movement of the joint lifter B


305


, as shown in

FIG. 33

, first the atmosphere communication opening B


404


of the suction cap B


310


is closed by the atmosphere communication valve B


405


. The joint lifter B


305


is further moved up, as a result thereof, as shown in FIG.


34


and

FIG. 24

, the needle B


122


of the sub-tank B


400


is completely inserted in the joint rubber C


108


of the joint C


105


, and the suction joint B


302


is connected with the air suction opening B


123


of the carriage B


104


. As a result, an ink supply passage between the medium pack C


100


and the sub-tank B


400


and an air suction passage between the sub-tank B


400


and the cylinder pump B


410


are formed (

FIG. 29

, step S


6


).




(Ink Supply, Wasting)




In the state that the ink supply passage and the air suction passage are formed as described above, the pump motor M


004


starts rotation in the reverse direction. This rotates the screw rod B


460


in the reverse direction, and the piston B


411


of the cylinder pump B


410


is retreated in the right direction from the state shown in

FIG. 19

to the state shown in FIG.


21


.




During retreating of the piston B


411


, the pump HP sensor B


321


detects that the piston B


411


of the cylinder pump B


410


is out of the home position (

FIG. 29

, step S


7


).




As described above, in association with retreat movement of piston B


411


, the air suction chamber B


413


is pressure reduced and the ink suction chamber B


414


is pressurized.




By this operation, air in the sub-tank B


400


is sucked to the air suction chamber B


413


through the porous film B


402


, the negative pressure introducing section B


406


, the air suction opening B


123


, the suction joint B


302


, and the suction tube B


303


. As a result, as shown in

FIG. 35

, ink is supplied from the main tank C


103


of the medium pack C


100


to the sub-tank B


400


through the ink supply passage C


200


of the medium pack C


100


, the joint C


105


and the needle B


122


of the sub-tank B


400


(

FIG. 29

, step S


8


).




On the other hand, since the ink suction chamber B


414


of the cylinder pump B


410


is pressurized in association with retreat movement of the piston B


411


, ink stored in the ink suction chamber B


414


is flowed to the waste ink absorption body C


107


of the medium pack C


100


through the waste liquid tube B


312


and absorbed and held by the waste ink absorption body C


107


.




As described above, since waste ink is wasted into the waste ink absorption body C


107


in the detachable medium pack C


100


, the waste ink will not be remained in the printer section B


100


.




In the second half stage of retreat movement of the above piston B


411


, as shown in FIG.


20


and

FIG. 21

, position switching of the valve rubber B


440


is performed. That is, as shown in

FIG. 20

, the tip flange part B


419


of the piston B


411


contacts against the valve rubber B


440


to press it, whereby the valve rubber B


440


and the plurality of slide pins B


442


are moved in the right direction to the position shown in FIG.


21


. As a result, as shown in

FIG. 21

, the input port B


416


connected to the suction cap B


310


through the suction tube B


311


is opened, and the output port B


417


connecting to the waste ink absorption body C


107


is closed by the valve rubber B


440


.




After the piston B


411


of the cylinder pump B


410


is moved to almost the stroke end at the retreat side shown in

FIG. 21

, it is allowed to remain stopping by for a predetermined setting time (for example, 1.5 sec.) (FIG.


29


, step S


9


).




(Suction Recovery)




Next, by forward rotatively driving the joint motor M


003


to move down the joint lifter B


305


by a predetermined distance, as shown in FIG.


36


and

FIG. 25

, the joint C


105


and the suction joint B


302


are moved down to the position to suck the ink of the suction cap B


310


(

FIG. 29

, step S


10


). That is, the suction joint B


302


is released from the air suction opening B


123


of the carriage B


104


, and the joint rubber C


108


of the joint C


105


is disconnected from the needle B


122


of the sub-tank B


400


. At this moment, the needle cover B


124


is moved down to the position for protecting the opening of the needle B


122


by the righting force of the spring (see FIG.


25


). Further, in this state, the atmosphere communication opening B


404


of the suction cap B


310


is still closed by the atmosphere communication valve B


405


, and in the cylinder pump B


410


, as shown in

FIG. 21

, the ink suction chamber B


414


is communicated with the suction tube B


311


.




In this state, by forward rotating the pump motor M


004


to rotate the screw rod B


460


, the piston B


411


of the cylinder pump B


410


is traveled to the left direction by about ¼ stroke from the state shown in

FIG. 21

(

FIG. 29

, step S


11


).




In association with the travel movement of the piston B


411


, the air suction chamber B


413


is pressurized and the ink suction chamber B


414


is pressure reduced.




By this operation, as shown in

FIG. 37

, the inside of the suction cap B


310


connected to the ink suction chamber B


414


through the suction tube B


311


is pressure reduced, as a result thereof ink is sucked from the ink ejection opening B


121


of the recording head B


120


and stored in the suction cap B


310


. In association with this ink suction operation, air is sucked through the air suction opening B


123


and the opening of the needle B


122


, thereby introducing sucked air to the porous film B


402


and the needle peripheral part.




Here, needle hole of the needle B


122


of the sub-tank B


400


also serves as an atmosphere communication hole, however, when residual air in the tank B


400


is expanded, there is a possibility that supplied ink is pushed out from the needle B


122


.




Then, immediately after performing ink supply to the sub-tank B


400


, joint connection is separated, and in this state ink suction is performed from the ink ejection opening B


121


to suck a predetermined amount of ink to flow in air from the needle hole of the needle B


122


, thereby providing an air space in the tank B


400


. By this operation, even when residual air is expanded, only air is discharged from the ink supply needle B


122


, thereby preventing ink leakage.




(Empty Suction)




Next, by further forward rotatively driving the joint motor M


003


to move down the joint lifter B


305


by further predetermined distance, as shown in FIG.


38


and

FIG. 26

, the atmosphere communication valve B


405


is move down to the open position. By this operation, the atmosphere communication opening B


404


of the suction cap B


310


is opened (

FIG. 29

, step S


12


).




In this state, by further forward rotating the pump motor M


004


to rotate the screw rod B


460


, the piston B


411


of the cylinder pump B


410


is traveled to the left direction to the ink supply start position shown in FIG.


19


through the stand-by position shown in

FIG. 18

further from the position traveled as described above by about ¼ stroke (

FIG. 29

, steps S


13


, S


14


).




By this operation, the ink suction chamber B


414


is further pressure reduced, and as a result thereof, as shown in

FIG. 38

, ink stored in the suction cap B


310


is flowed into the ink suction chamber B


414


of the cylinder pump B


410


through the ink suction tube B


311


. Further residual ink in the suction tube B


311


is also flowed into the ink suction chamber B


414


. By performing such empty suction, color mixing in respective nozzles is prevented.




In the course of travel movement to the left direction of the piston B


411


, the pump HP sensor B


321


detects that the piston B


411


is positioned at the home position at the time when the piston B


411


of the cylinder pump B


410


is traveled to the position shown in

FIG. 18

(

FIG. 29

, step S


13


).




Further, when the piston B


411


of the cylinder pump B


410


is traveled from the state shown in

FIG. 18

to the ink supply position shown in

FIG. 19

, as described above, by the movement of the pressure slider B


431


, switching of valve rubber B


440


and upward protrusion operation of the wiper C


106


of the medium pack C


100


through the wiper lifter B


316


are carried out (

FIG. 29

, step S


14


).




(Suction Cap Open)




Next, by forward rotatively driving the joint motor M


003


to move down the joint lifter by further predetermined distance, as shown in

FIG. 39

, the suction cap B


310


is caused to separate from the face B


403


of the recording head B


120


and make the suction cap B


310


an open state (

FIG. 29

, steps S


15


, S


16


). By the downward movement of the joint lifter B


305


, the joint C


105


and the suction joint B


302


are also further moved down. Further, during the downward movement of the joint lifter B


305


, when the joint lifter B


305


is at a predetermined stand-by position, the joint HP sensor B


322


detects that the joint lifter B


305


is positioned at the home position.




(Wiping)




In this state, after the carriage motor M


001


is driven, the carriage B


104


is moved to the position of the wiper C


106


of the medium pack C


100


, and at this wiper position, the carriage B


104


is reciprocally moved once to a plurality of times, it is returned to the original home position (

FIG. 29

, step S


17


). By this operation, ink adhered to the face B


403


of the recording head B


120


is wiped by the wiper C


106


.




As described above, since wiping is performed using the wiper C


106


provided on the medium pack C


100


, scattering of ink at the printer section B


100


side is prevented.




After completion of the wiping, the pump motor M


004


is reverse rotated to rotate the screw rod B


460


, thereby retreating the piston B


411


of the cylinder pump B


410


in the right direction from the position shown in

FIG. 19

to the stand-by position shown in FIG.


18


. By the rotation of the screw rod B


460


, the pressure slider B


431


is also moved to the right, thereby also moving the plate cam member B


450


in the right direction by the righting force of the spring B


453


. As a result, the wiper lifter B


316


engaging with the cam part B


451


of the plate cam member B


450


is moved down, and the wiper C


106


of the medium pack C


100


is also retreated.




Thus, one cycle of ink supply and suction recovery operation is completed, and printing by the printer section B


100


becomes possible.




(Printing)




In the printer section B


100


, the carriage B


104


is moved and the recording head B


120


is driven while transporting a sheet of printing medium C


104


taken out from the medium pack C


100


, thereby performing the instructed predetermined printing operation (

FIG. 29

, step S


19


).




When printing is subsequently performed after the end of printing to a sheet of a printing medium, the procedure is returned to step S


4


. Thereafter, the processing above step S


4


to S


19


is performed again, that is, ink supply for printing next page, suction recovery operation and printing next page are performed.




As described above in the present apparatus, since ink supply and suction recovery operation are performed every time a sheet is printed, a high-quality printing can be stably performed. Further, when printing is ended, the following steps S


20


to step S


24


are carried out following step S


19


.




(Wiping)




At the end of printing, the cylinder pump B


410


is in stand-by state as shown in FIG.


18


. From this state, the pump motor M


004


is forward rotatively driven to rotate the screw rod B


460


, for moving the pressure slider B


431


in the lift direction to the state shown in FIG.


19


. By this operation, the plate cam member B


450


is moved to the left, and the wiper lifter B


316


is also moved up. As a result, the wiper C


106


of the medium pack C


100


is protruded (

FIG. 29

, step S


20


).




Next, by driving the carriage motor M


001


to reciprocally move the carriage B


104


at the wiper position, ink adhered to the face B


403


of the recording head B


120


during printing is wiped by the wiper C


106


(

FIG. 29

, step S


21


).




Next, by reverse rotatively driving the pump motor M


004


to reverse rotate the screw rod B


460


, the pressure slider B


431


is moved from the state shown in

FIG. 19

to the position shown in FIG.


20


. By this operation, the plate cam member B


450


is moved to the right, the wiper lifter B


316


is moved down, and the wiper C


106


of the medium pack C


100


is retreated (

FIG. 29

, step S


21


).




After that, when it is detected that the carriage B


104


reverts back to the home position (

FIG. 29

, step D


22


), the joint motor M


003


is reverse rotatively driven to slightly move up the joint lifter B


305


and the suction cap B


310


is also moved up. By this operation the face B


403


of the recording head B


120


is capped by the suction cap B


310


(

FIG. 29

, step S


24


).




(Preliminary Ejection)




Although omitted in the above operation sequence, preliminary ejection operation for intentionally ejecting ink from the ink ejection opening B


121


of the recording head B


120


to the suction cap B


310


or the like may be performed after wiping of step


18


of FIG.


29


. Further, as necessary, preliminary ejection may be performed at an appropriate time.




As described in the above embodiment, since the cylinder pump B


410


uses one side cylinder chamber of the piston B


411


as air suction chamber B


413


, the other side cylinder chamber as ink suction chamber B


414


, so that the respective cylinder chambers perform suction operation by reciprocal operation of the piston B


411


, this configuration greatly contributes to down-sizing of the pump construction. Further, since, rather than by switching the valve provided outside the cylinder pump B


410


, by positional switching of valve rubber


440


provided inside the pump cylinder B


304


, ink suction and ink discharge of the ink suction chamber B


414


are switched, the pump structure can be reduced in size. Further, since the screw rod B


460


is engaged inside the piston shaft B


441




a


to move the piston B


441


, as compared with the case in which another member connected to the piston shaft B


441


is engaged with the screw rod B


460


, the structure for reciprocally moving the piston shaft


441


is reduced in size.




Further, in the present embodiment, a relief valve B


420


is provided in the piston shaft B


411




a


of the cylinder pump B


410


to take less space and to prevent the porous film B


402


from being applied with an excessive ink pressure during ink supply, whereby assuring reliable operation of the porous film B


402


.




Further, in the present embodiment, the cylinder chamber B


414


inserting the piston shaft B


411




a


is used for ink suction, and the other cylinder chamber B


413


for air suction. Therefore, suction amounts of the respective cylinder chambers B


413


and B


414


can be set to different values for the same stroke. Therefore, by changing the shaft diameter of the piston shaft B


411




a


, the suction volume ratio of the ink suction chamber B


414


and the air suction chamber B


413


can be easily changed.




(Second Embodiment)




Next, with reference to

FIGS. 40

to


47


, a second embodiment by another pump unit including the cylinder pump B


500


will be described.




The cylinder pump B


500


, which is a main component of such a pump unit, in the present embodiment, as shown in

FIGS. 40A

,


40


B, a piston B


521


slidably moving in the cylinder B


531


of the pump has an elliptical cross section. Accordingly, the cross section of the cylinder B


531


, which is also used as an external case of the cylinder pump B


500


, is also nearly elliptical.




Because the cross section of the piston of the pump is elliptical, when the pump is disposed in the printer, its height can be suppressed, which contributes to a reduced height of the entire printer. For example, as compared with the case of using a piston with a circular cross section of the same height in the disposed state, the elliptical cross section can provide a greater cross sectional area of the cylinder, which provides a shorter stroke, thereby providing a smaller size in the pump height and longitudinal direction. As described above, when the installation space of the pump in the printer has a room to some extent in the longitudinal direction of the ellipse, or when suppression of the printer height is preferential from the design, as in the present embodiment, it is effective that the cross sectional shape of the piston is made elliptical, and accordingly the cross sectional shape of the cylinder is made elliptical.




In particular, as in the present embodiment, in the case of the printer integral with a camera, it is effective because the printer height is limited. Specifically, as shown in

FIGS. 5 and 6

, the printer section B


100


, from the requirement of integral camera, the cross section is rectangular, on the other hand, the cylinder pump B


500


and its drive mechanism and the like are substantially required to be disposed in the lower half of the printer section B


100


, that is, in the lower side of the transportation path of the printing medium. Therefore, the elliptical cross sectional shape in the present embodiment is preferable because the height of the cylinder pump B


500


is a height to be under side of the transportation path and the cross sectional area inside the cylinder is ensured to obtain an effective suction force with a limited stroke.




Further, when considering gas-tightness of the piston to the cylinder, the elliptical shape is advantageous for applying a uniform pressure to the inner surface of the cylinder as compared to, for example, one which includes a straight part in the cross sectional shape.




As can be seen from the above description, the cross sectional shape of the piston is not necessarily required to be elliptical. A flattened shape with a suppressed height of one side can provide the above desired function. Preferably it is one which does not include a straight part in the shape in view of sealing with the cylinder.




The cylinder pump B


500


, as will be described later, according to a predetermined rotation of the lead screw B


510


, is a generation source of pressure for ink supply to respective ink reserving section of the carriage B


104


and ink suction through the suction cap B


310


.

FIG. 41

is a diagram showing internal structure of the cylinder pump B


500


for this purpose.




As shown in

FIG. 41

, the cylinder pump B


500


, as main elements, comprises a cylinder main body B


531


, a piston B


521


and a piston shaft B


522


. The cylinder main body B


531


, as described above, also comprises a case as an outer shape of the cylinder pump B


500


, which is fixed to the printer. On the other hand, the piston shaft B


522


is connected with a pump driving arm B


509


whereby the piston B


521


can move in the cylinder B


531


according to the rotation of the lead screw B


510


.




The piston B


521


is engaged with the inner wall of the cylinder main body B


531


through an O-ring provided at its end. This makes the parts (air suction chamber and ink suction chamber) partitioned by the piston B


521


of the cylinder inside B


531




a


non-communicational with each other and slidable with the inner wall.




The piston shaft B


522


has a valve B


522


A formed at its one end, and has a hollow part B


522


B extending in the axial direction. The valve B


522


A, according to the movement of the piston shaft B


522


, can move freely in the inner space formed inside the piston B


521


. According to the movement, when the sealing part formed of a flexible material such as rubber closely contacts with the inner upper surface B


521




a


of the inner space so as to surround the opening of the hollow part B


522


B above the valve B


522


A, the hollow part B


522


B of the piston shaft B


522


and the cylinder inside B


531




a


(ink suction chamber) can be made non-communicational with each other and air-tight. On the other hand, when the valve B


522


A contacts against the inner lower surface B


521




b


of the inner space, the hollow part B


522


B of the piston shaft B


522


and the cylinder inside (ink suction chamber)


531




a


are communicational through a groove (not shown) formed on the lower surface of the valve B


522


A.




At the upper end (left side in the figure) of the cylinder B


531


, an air introduction opening B


532


is formed. The air introduction opening B


532


communicates with a suction joint B


302


shown in

FIG. 40A

, whereby at the time when ink is supplied from the medium pack C


100


to respective ink reserving section of the carriage B


104


, air suction can be performed. Further, at the upper end of the cylinder main body B


531


, a pressure adjusting valve mechanism B


525


is provided. The pressure adjusting valve is possible to adjust a pressing force by its spring. When the negative pressure of the cylinder inside (air suction chamber) B


531




a


between the cylinder main body B


531


and the piston B


521


becomes a magnitude corresponding to the adjusted pressing force (when the pressure decreases to the corresponding value), the valve opens and, as a result, the negative pressure is adjusted to a constant value. By this operation, the air suction can be performed at a consistent negative pressure.




On the other hand, at the lower end (right side in figure) of the cylinder B


531


, a sealing member B


524


is provided. The sealing member B


524


is possible to make the cylinder inside B


531




a


airtight to the outside and slidable with the piston shaft B


522


B while keeping the same air-tightness. The sealing member B


524


is provided with an ink introduction opening B


523


, which communicates with the suction cap B


310


shown in FIG.


40


A. This makes it possible to introduce waste ink sucked through the suction cap B


310


to the inside the cylinder (ink suction chamber) B


531




a


. In this communication passage, a check valve (not shown) is provided, whereby ink from the suction cap B


310


is passed and, to the contrary, ink flow discharged from the cylinder inside (ink suction chamber) B


531




a


can be blocked.




With the above construction, when ink is supplied from the ink pack of the medium pack C


100


to respective ink reserving section of the sub-tank B


400


of the carriage B


104


, by predetermined rotation of the lead screw B


510


, the piston B


521


moves downward (in the direction of arrow B in FIG.


41


), so that generates a negative pressure in the cylinder inside B


531




a


(air suction chamber). By this negative pressure, air is sucked from respective ink reserving section of the carriage B


104


communicating with the cylinder inside (air suction chamber) B


531




a


through the suction joint B


302


and the like, thereby making the inside of the ink reserving section negative pressure and introducing ink from the ink pack to respective ink reserving section. At this time, only air passes through the above porous film B


402


, and ink passage is blocked. When the introduced ink reaches the porous film further suction is not performed due to a pressure balance or the like.




During the downward movement of the piston B


521


in the cylinder main body B


531


, waste ink sucked through the suction cap B


310


in the previous process to the cylinder inside (ink suction chamber) B


531




a


once flows to the upper side of the valve B


522


A through a groove formed on the lower surface of the valve B


522


A, and then discharged through the hollow part B


522


B of the piston shaft B


522


. The discharged waste ink is passed through the inside passage and the like of the pump driving arm B


509


, and finally to the waste ink absorption body C


107


of the medium pack C


100


.




On the other hand, in the suction recovery operation, by predetermined rotation of the lead screw B


510


, the piston B


521


moves up (in the direction of arrow A in

FIG. 41

) in the cylinder. By this operation, a negative pressure is generated in the cylinder inside (ink suction chamber) B


531




a


, so that the inside of the suction cap B


310


connecting with it and covering the nozzle disposition surface of the recording head can be made negative pressure. By this negative pressure, ink discharged through the nozzle can be conducted to the cylinder inside (ink suction chamber) B


531




a


. At this time, as described above, the valve B


522


A of the piston shaft B


522


closely contact with the upper surface of the inner space of the piston, the cylinder inside B


531




a


and the hollow part B


522


B of the piston shaft B


522


are in the air-tight state with each other, thus maintaining air-tightness.




During the upward movement of the piston B


521


, simultaneously, air above the piston (air in the air suction chamber) is discharged towards the suction joint B


302


through the air introduction opening. At this time, since the suction joint B


302


is released from connection with the carriage B


104


, a case is prevented that the discharged air reaches the ink reserving section of the carriage and pressures the recording head from the inside.




With the above described construction of the cylinder pump B


500


, unlike the pump unit in the first embodiment, since the hollow part B


522


B of the piston shaft B


522


is used as an ink discharge passage, it is not necessary to provide a switching valve in the cylinder as seen in the pump used in suction recovery processing in the first embodiment. Therefore, a piston stroke for position adjustment of the valve with the piston is needless to be considered, as a result thereof, the piston stroke can be reduced. Further, since the pressure adjusting mechanism is provided outside the cylinder, in the production of the pump, assembly or incorporation process can be made easy.




The lead screw B


510


, as described above, has a role of function of power transmission of various operations and setting of timing, including ink supply operation from the medium pack C


100


to the ink reserving section of the carriage B


104


or suction recovery operation through the suction cap B


310


. The lead screw B


510


, as shown in

FIG. 40A

, has two spiral grooves B


510




a


and a single spiral groove B


510




b


formed with a predetermined distance from the former groove. The spiral groove B


510




a


is engaged with part of pump slider B


541


to move the pump driving arm B


509


. On the other hand, the spiral groove B


510




b


is engaged with part of switching slider B


512


, whereby moving the switching slider B


512


.




Operations performed by the movement of the pump slider B


541


, as described above, are ink supply to the ink reserving section, suction recovery and wiping. On the other hand, operations performed by the movement of the switching slider B


512


are capping operation of the suction cap B


310


to the recording head and releasing operation of the joint B


501


and the carriage B


104


.





FIG. 42

is a diagram for explaining the relationship between the lead screw B


510


and a driving force transmission mechanism of pump motor M


004


for generating a driving force for rotating the same and the above various operations by the lead screw B


510


. In this figure, the conveying motor M


002


for supply of printing medium and transmission mechanism thereof are also shown.




In the following, with reference to the operation positions of the driving arm B


509


and operation position of the switching slider B


512


shown in

FIG. 42

, and

FIGS. 43

to


47


, power transmission and setting of timing of various operations by the lead screw B


510


will be described.





FIG. 43

shows the positions of the pump slider B


541


and the switching slider B


512


when the wiper and the suction cap B


310


are at the ascended positions. At this time, the pump slider B


541


is positioned at the left end relative to the spiral groove B


510




a


of the lead screw B


510


, by movement to this left end, the wiper pressure part B


541




a


of the pump slider B


541


is moved. The wiper pressure part B


541




a


, by its movement, as shown in

FIG. 44

, pushes up part of the plate spring-formed receiving part B


542




b


of the wiper base B


542


which supports its end part B


542




a


by a predetermined member. By this operation, the wiper B


543


becomes a rising state. At the same time, the releasing valve arm B


541




b


connecting at the tip of the wiper pressure part


541




a


pushes the releasing lever B


544




a


, as shown in

FIG. 47C

, to drive the lever and the releasing valve plate B


544




b


cooperating with this lever, and to move atmosphere communication valves B


545


(

FIGS. 46B and 46C

) to atmosphere communication positions. Further, by the movement to the left end, the above-described suction recovery processing can also be performed.




At this moment, the other switching slider B


512


is at the right end relative to the spiral groove B


510




b


of the lead screw B


510


, whereby the cap lever arm B


514


is at the position where the suction cap B


310


(not shown) is moved up (cap close; capping state). That is, the switching slider B


512


is partly connected to the cap lever arm B


514


, by the movement to the right of the switching slider B


512


, the cap lever arm B


514


is rotated, and the part B


514




a


can be moved up the position where the suction cap B


310


is moved up.





FIG. 45

is a diagram showing the state of other positions relative to the respective spiral grooves of the pump slider B


541


and the switching slider B


512


shown in

FIGS. 43 and 44

. The figures show the state when the pump slider B


541


is at the right end relative to the spiral groove B


510




a


and the switching slider B


512


is in the middle of the spiral groove B


510




b.






At this moment, the wiper pressure part B


541




a


is at the retreated position from the pushed-up position of the wiper base B


542


, whereby the wiper B


543


is at the retreated position from the movement range of the carriage B


104


. Further, when the joint B


501


is in the state connected with respective needles of the carriage, by the movement to the right end, ink supply to the ink reserving section by the above pit-in can be performed. Further, at this time, the releasing valve arm B


541




b


of the pump slider B


541


is in the state shown in

FIG. 47A

, the atmosphere communication valve B


545


of the suction cap B


310


is in valve-close state as shown in FIG.


46


C.




On the other hand, by moving the switching slider B


512


to the left, the cap lever arm B


514


is rotated, whereby its part B


514




a


is pressed down and the suction cap B


310


can be made open state.




As described above, the state described with reference to

FIGS. 43

to


47


is a basic example of the positions of the pump driving arm and the switching slider according to the rotation of the lead screw B


510


. That is, by the clockwise rotation or counterclockwise rotation of the lead screw B


510


, the spiral groove B


510




a


and the spiral groove B


510




b


, by appropriately determining the formation ranges or lengths thereof and the densities of spiral grooves, as in the first embodiment, the above described basic operations are made possible, and by combinations of these, various processing using the pump motor M


004


are made possible. For example, in the above description, upward movement of the suction cap B


310


and rising of the wiper C


106


are performed simultaneously, only the wiper rising can be performed.




As described above, with the present invention, since different fluids such as air and ink are flowed in the cylinder chambers on both sides of the piston, by reciprocal movement of the piston, suction of different fluids are performed by these respective cylinder chambers, a compact pump can be provided. Further, since suction discharge operation in one cylinder chamber is switched by port switching means provided in the cylinder, the pump structure can be made compact. Further, since the screw rod is engaged inside the piston shaft to move the piston, the pump structure can be reduced in size.




Further, since a relief valve is provided in the piston of the pump cylinder, the pump structure can be reduced in size. Still further, the porous film is prevented from being applied with an excessive pressure during ink supply, whereby assuring reliable operation of the porous film.




Further, since the piston shaft is inserted in one cylinder chamber of the pump cylinder, suction amounts of the respective cylinder chamber can be set to different values with the same piston stroke. Therefore, by changing the shaft diameter of the piston shaft, the suction volume ratio of both ink suction chambers can be easily changed.




The present invention has been described in detail with respect to preferred embodiments, and it will now be apparent from the foregoing to those skilled in the art that changes and modifications may be made without departing from the invention in its broader aspect, and it is the intention, therefore, in the apparent claims to cover all such changes and modifications as fall within the true spirit of the invention.



Claims
  • 1. A cylinder pump unit comprising:a cylinder pump including a reciprocally movable piston and a cylinder main body having a first cylinder chamber partitioned at one side of said piston and introduced with air and a second cylinder chamber partitioned at the other side of said piston and introduced with ink, wherein said second cylinder chamber has an input port for sucking ink and an output port for discharging ink; a piston driving means for reciprocally moving said piston of said cylinder pump, wherein a piston shaft of said piston is extended to outside said cylinder main body through said second cylinder chamber and connected to said piston driving means; and a port switching means for performing switching of opening and closing of said input port and said output port in association with movement of said piston so that when said second cylinder chamber is pressure reduced by movement of said piston, said output port is closed and said input port is opened, and when said second cylinder chamber is pressurized by movement of said piston, said input port is closed and said output port is opened.
  • 2. A cylinder pump unit according to claim 1, wherein said port switching means is incorporated in said second cylinder chamber.
  • 3. A cylinder pump unit according to claim 1, whereinsaid piston driving means comprises a screw rod engaging with said piston shaft, and rod driving means for rotatively driving said screw rod.
  • 4. A cylinder pump unit according to claim 1, whereinsaid piston driving means comprises a pump driving arm for connecting through said piston shaft; a lead screw engaging with said pump driving arm for reciprocally driving said pump driving arm; and screw driving means for rotatively driving said lead screw.
  • 5. A cylinder pump unit according to claim 1, wherein said first cylinder chamber is connected with an air suction part provided with a porous film in an ink tank, said air suction part introduces a negative pressure that supplies ink from intake into the ink tank, andsaid piston shaft is a hollow cylindrical body and provided with a relief valve at a tip of said piston shaft for maintaining suction pressure of said first cylinder chamber at less than a predetermined pressure.
  • 6. A cylinder pump unit according to claim 5, wherein a setting relief pressure of said relief valve is set smaller than a pressure capable of maintaining performance of said porous film.
  • 7. A cylinder pump unit according to claim 1, wherein cross sectional form of said cylinder pump is elliptical.
  • 8. A cylinder pump unit comprising:a cylinder pump including a reciprocally movable piston and a cylinder main body having a first cylinder chamber partitioned at one side of said piston and introduced with air and a second cylinder chamber partitioned at the other side of said piston and introduced with ink; wherein said second cylinder chamber has an input port for sucking ink; a piston driving means for reciprocally moving said piston of said cylinder pump; a piston shaft of said piston, which is extended to outside said cylinder main body through said second cylinder chamber and connected to said piston drive means, wherein said piston shaft has a hollow cylindrical form, and said hollow part is an output port for discharging ink; and a port switching means for performing switching of opening and closing of said input port and output port in association with movement of said piston so that when said second cylinder chamber is pressure reduced by movement of said piston, said output port is closed and said input port is opened, when said second cylinder chamber is pressurized by movement of said piston, said input port is closed and said output port is opened.
  • 9. A cylinder pump unit according to claim 8, whereinsaid port switching means is a check valve provided in a passage communicating with said input port and a check valve provided between said piston and said piston shaft.
  • 10. A cylinder pump unit according to claim 8, whereinsaid piston driving means comprises a screw rod engaging with said piston shaft, and rod driving means for rotatively driving said screw rod.
  • 11. A cylinder pump unit according to claim 8, whereinsaid piston driving means comprises a pump driving arm for connecting through said piston shaft; a lead screw engaging with said pump driving arm for reciprocally driving said pump driving arm; and screw driving means for rotatively driving said lead screw.
  • 12. A cylinder pump unit according to claim 8, wherein said first cylinder chamber is connected with an air suction part provided with a porous film in an ink tank, said air suction part introduces a negative pressure that supplies ink from intake into the ink tank, andsaid piston shaft is a hollow cylindrical body and provided with a relief valve at a tip of said piston shaft for maintaining suction pressure of said first cylinder chamber at less than a predetermined pressure.
  • 13. A cylinder pump unit according to claim 12, wherein a setting relief pressure of said relief valve is set smaller than a pressure capable of maintaining performance of said porous film.
  • 14. A cylinder pump unit according to claim 8, wherein cross sectional form of said cylinder pump is elliptical.
Priority Claims (2)
Number Date Country Kind
2000-277226 Sep 2000 JP
2001-081642 Mar 2001 JP
US Referenced Citations (1)
Number Name Date Kind
6612683 Takahashi et al. Sep 2003 B2
Non-Patent Literature Citations (1)
Entry
0018-8689-24-1A-255 Jun. 1981 IBM.