Patent Application
20050270342
1. Field of the Invention
The present invention relates to a liquid supplying apparatus that supplies a liquid to a print head, and in particular, a liquid supplying apparatus having a liquid housing container detachable from the print head.
2. Description of the Related Art
Ink jet printing apparatuses form an image on a print medium by using a print head to eject a liquid such as ink or a solvent to the print medium. The ink jet printing apparatus includes a serial printer type and a line printer type. A serial printer type printing apparatus forms an image by ejecting the liquid while intermittently conveying the print medium and when the print medium is stopped, moving the print head together with a carriage in a direction orthogonal to a conveying direction. Further, a line printer type printing apparatus has an elongate print head fixed to the main body of the apparatus and consisting of nozzles arranged over at least the maximum print range of the print medium. Thus, the line printer type printing apparatus forms an image by ejecting the liquid from the print head while moving the print medium with respect to the print head.
What is called an on-carriage system is applied to the serial printer type printing apparatus in order to supply the liquid to the print head. With this system, a liquid housing container is integrally and inseparably or separably attached to the print head mounted on a carriage or the like and reciprocate (main scanning). The liquid from the liquid housing container is supplied directly to the print head.
Further, with what is called a tube supplying system, the liquid is supplied by fixedly installing the liquid housing container in another site of the printing apparatus and connecting the liquid housing container and the print head together. The tube supplying system includes a form in which a second liquid housing container functioning as a subtank between the liquid housing container (main tank) and the print head is mounted on the print head or carriage. In this form, the liquid in the second liquid housing container is supplied directly to the print head.
These liquid supplying systems are provided with a mechanism that generates a negative pressure inside the liquid housing container from which the liquid is fed directly to the print head. The negative pressure generating mechanism generates a negative pressure to the extent that the liquid is prevented from leaking inadvertently from a liquid ejecting section of the print head, while the print head can perform an ejecting operation.
When a liquid supply port in the liquid housing container is connected to a liquid supplying section provided in the head, the liquid from the liquid housing container is supplied to nozzles in the print head. Further, an ejection energy generating element (heater or piezoelectric element) is provided in each of the nozzles arranged in the print head; the ejection energy is used to eject ink. The ejection energy generating element is driven in response to a signal from the printing apparatus main body to eject the ink to a print medium to form an image.
Common means for connecting the print head and the liquid housing container together have such configurations as described below.
Japanese Utility Model Laid-Open No. 1994-34108 discloses an arrangement in a connection structure composed of the liquid supplying tube (needle) and an elastomer (rubber portion), the arrangement allowing the needle to be appropriately inserted into an ink cartridge. In this connection structure, the needle 6 is attached to a needle fulcrum that rotatably supports the needle 6 so as to absorb a shift in or the inclination of the needle. Moreover, in this connection structure, for improved aligning accuracy, alignment is carried out using a needle guide provided at a position closer to the leading end of the needle than to the fulcrum.
This conventional technique executes alignment of the needle with the elastomer near the needle in order to more accurately set the position into which the needle is inserted. After the alignment, the needle is rotatably supported on the needle fulcrum so as to be smoothly guided to a needle seal holding member. However, this conventional technique has no needle seal structure and does not give sufficient considerations for detachment or a fixing technique. Thus, when the ink cartridge is removed, the liquid may leak. Further, since the needle is held by the repulsive force of the elastomer around the needle, the durability of the needle may be affected or creep may occur. Further, the above publication mentions the rotatability of the needle fulcrum, but does not clearly describe a specific mechanism for making the needle fulcrum rotatable. It also fails to clarify the effects of the rotatability.
Further, Japanese Patent Laid-Open No. 1977-150031 discloses a configuration in which concave and convex portions are formed near the head supply port and interlock with concave portions provided on the tank. With this configuration, after the needle is inserted into the tank, the tank itself is rotated to fix the tank and the print head.
The technique disclosed in Japanese Patent Laid-Open No. 1977-150031 requires the housing container to be precisely mounted to the liquid supply tube in order to interlock the concaves in a peripheral portion of the head supplying port with the convexes on the liquid housing container. Further, with this technique, after the tank is inserted around the needle, the tank must be manually rotated. This degrades operability. Moreover, the housing container is cylindrical and a large dead space is thus expected to be created in the printer main body.
Japanese Patent Laid-Open No. 1977-150031 also discloses a seal member 14 that seals the liquid supplying tube to the head. However, the rotation of the container disclosed in this publication is carried out after the container has been completely inserted around the needle. Thus, the seal member may be stuck to the liquid supplying tube to increase an operating force required to rotate the container.
Japanese Patent Laid-Open No. 1999-245431 discloses an arrangement that prevents the leakage of the liquid or installation errors. In this arrangement, a cam surface is provided on the liquid housing container. To install the liquid housing container, a bayonet connector that can rotatably move relative to the main body is rotated along the cam surface to fix the liquid housing container. According to Japanese Patent Laid-Open No. 1999-245431, the rotative moving member, which rotatably moves in association with installation, is provided on the head. The characteristic shape of the rotative moving member allows installation errors to be prevented. Further, rotation of the rotative moving member improves the fixture and sealing.
However, Japanese Patent Laid-Open No. 1999-245431 requires the whole liquid housing container to be rotated when it is to be removed. This degrades the operability. Another problem with Japanese Patent Laid-Open No. 1999-245431 is that since the disclosed housing container is a rectangular parallelepiped, an extremely large dead space may be created when the housing container is removed.
Further, Japanese Utility Model Laid-Open No. 1988-178141 discloses an arrangement intended to prevent the ink from scattering (leaking) by rotating the liquid housing container 1 in order to remove it. In this arrangement, a releasing projection is provided on the tank so that the head and the tank can be rotatably moved relative to each other so as to be separated from each other. When the tank is rotatably moved, the projection operates like a cam to separate the head from the tank.
However, with the structure described in Japanese Utility Model Laid-Open No. 1988-178141 and which allows the attachment and detachment of the liquid housing container to and from the print head, the whole liquid housing container must be rotated during an attaching or detaching operation. This disadvantageously degrades the operability and results in a larger dead space in the main body.
As described above, with the arrangements shown in the above publications and provided for the connection between the print head and the liquid supplying tube to the print head, an increase in installing force required may result from the sticking of the seal portion to the liquid supplying tube to the head, the misalignment between the seal portion and the liquid supplying tube, or the like. Further, disadvantageously, the liquid housing container may be tilted during attachment or detachment, thus degrading the operability.
It is an object of the present invention to provide a liquid supplying apparatus that enables a liquid housing container to be appropriately and smoothly attached to and detached from a print head.
To achieve this object, the present invention has the following configuration.
A first aspect of the present invention is a liquid supplying apparatus which supplies a liquid to a print head, the apparatus being characterized by comprising a liquid supplying tube projected from the print head and having a liquid introducing port which is in communication with the print head, a seal member rotatably movably held on the liquid supplying tube, the seal member being movable from a position at which the liquid introducing port is closed to a position at which the liquid introducing port is opened, a housing container main body in which the liquid is housed, the housing container main body having a liquid supplying port into and from which the liquid supplying tube can be inserted and removed, and a movable member which rotatably moves the seal member.
A second aspect of the present invention is a liquid housing container from which a liquid is fed via an ink liquid supplying tube to a print head having a liquid introducing port formed in the liquid supplying tube and which can be closed by a seal member rotatably movably supported on the liquid supplying tube, the container being characterized by comprising a housing container main body having a liquid supplying port into and from which the liquid supplying tube can be inserted and removed, and a movable member which rotatably moves the seal member.
A third aspect of the present invention is a driving force transmitting member which rotatably moves the seal member in association with an operation of attaching or detaching a liquid housing container from which a liquid is fed via the ink liquid supplying tube to a print head having a liquid introducing port formed in the liquid supplying tube and which can be closed by a seal member rotatably movably supported on the liquid supplying tube, the transmitting member being characterized by comprising an engaging portion which can be engaged with the seal member and in that the transmitting member is supported so as to be rotatably movable relative to the liquid housing container.
A fourth aspect of the present invention is a method for attaching and detaching a liquid housing container, the method being used to attach and detach a liquid housing container from which a liquid is fed via the ink liquid supplying tube to a print head having a liquid introducing port formed in the liquid supplying tube and which can be closed by a seal member rotatably movably supported on the liquid supplying tube, the method being characterized by comprising a step of engaging a rotatably movable driving transmitting member with the seal member, the driving transmitting member comprising an engaging portion which can engage with the seal member, a step of lowering the seal member while rotatably moving the driving transmitting member, a step of fixing the driving transmitting member, and a step of connecting the liquid housing container to a liquid supplying tube.
According to the present invention, during an attaching and detaching operation, the movable member rotates the seal member to enable the suppression of fixation of the seal portion caused by ink evaporation and of an increase in installation force caused by, for example, sticking of the seal member. Therefore, the liquid housing member can be easily and smoothly installed.
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.
1 is a perspective view showing how the rotative moving member operates in the step shown in
2 is a perspective view showing how the seal member operates in the step shown in
1 is a perspective view showing how the rotative moving member operates in the step shown in
2 is a perspective view showing how the seal member operates in the step shown in
1 is a perspective view showing how the rotative moving member operates in the step shown in
2 is a perspective view showing how the seal member operates in the step shown in
The present embodiment will be described by taking the case of a liquid housing container detachably provided in a print head used in such a serial printer type ink jet printing apparatus as previously described. In a common serial printer type ink jet printing apparatus, one or more liquid housing containers can be installed depending on the number of types of liquids used. However, for convenience, the embodiment will be described below by taking the case in which one liquid housing container is installed in the print head.
A first embodiment of the present invention will be described below in detail with reference to the drawings.
In
The housing container main body 1a is shaped like a rectangular parallelepiped as shown in
The rotative moving member 4 consists of an annular portion 4a rotatably movably fitted and held around an annular projection projected from a bottom surface of the housing container main body 1a and two arm portions 4b and 4c projected from the annular portion 4a and having different lengths. As shown in
On the other hand, a print head according to the present embodiment is an ink jet print head in which electrothermal converting elements (heaters) or electromechanical converting elements (piezoelectric elements) in a plurality of nozzles that eject a liquid are driven to eject the liquid from the nozzles, the liquid being fed from a liquid chamber formed in side the print head to the nozzles. A liquid supplying tube 13 is provided on a top surface of the print head 12 so as to extend in a direction orthogonal to the top surface. A lower end of the liquid supplying tube 13 is in communication with the liquid chamber in the print head 12. Further, a holder 11 holding the liquid housing container 1 is fixed to the top surface of the print head. The liquid supplying tube 13 is inserted through a through-hole formed in a bottom portion of the holder 11, and projects upward from the bottom portion.
Further, a seal member 14 is inserted around the liquid supplying tube 13 in order to prevent the leakage of a liquid from the print head 12. The seal member 14 is composed of a seal member inserted around the liquid supplying tube 13 so as to be movable along the liquid supplying tube 13 in its axial direction and rotative moving direction, and a holding member 14b that holds the periphery of the seal member. A pair of engaging projections (engaging portions) 15 is formed on a top surface of the holding member 14b; the engaging projections 15 can engage with engaging concave portions 5 in the rotative moving member 4. Moreover, a pair of protruding portions 14b1 are provided at opposite positions on a peripheral portion of the holding member 14b. Each of the paired protruding portions 14b1 is movably inserted into a corresponding one of paired bent grooves 17a extending vertically in the seal holding member 17 projected from the top surface of the holder. A coil spring 16 is elastically installed between the holding member 14b of the seal member 14 and the holder. The urging force of the coil spring 16 always urges the seal member 14 upward. Thus, if the liquid housing container is not installed, that is, if no downward pressing force is exerted on the seal member 14, the projecting portion 14b1 is held at a portion where it abuts against an upper end of the groove 17a. In this state, an inner peripheral surface of the elastomer 14a closes the liquid introducing port 13a to prevent the leakage of a liquid from the liquid introducing port 13a.
As shown
As shown in
Now, description will be given of operations performed when the liquid housing container configured as described above is attached or detached.
First, description will be given of operations performed when the liquid housing container 1 is installed.
The liquid housing container 1 is installed in the holder 11, shown in
As the housing container main body 1a is pressed downward, the ends 4b1 and 4c1 of the rotative moving member 4 lower along the guide grooves 18 and 19, respectively, and rotatably move in accordance with the inclinations of the guide grooves 18 and 19. The engaging concave portions 5 in the rotative moving member 4 engage with the respective engaging projections 15 on the seal member 14. On this occasion, the rotative moving member 4 rotates against the force of the coil spring, which urges the rotative moving member 4 in a rotating direction. After engaging with the seal member 14, the rotative moving member 4 continuously rotates along the guide grooves 18 and 19. Accordingly, the rotating force of the rotative moving member 4 is transmitted to the seal member 14. The seal member 14 is also rotated. Then, once the ends 4b1 and 4c1 of the rotative moving member 4 reach lower ends 18a and 19a of the guide grooves 18 and 19, the ends of the rotative moving member 4 rotate in a direction opposite to the previous one owing to the urging force of the coil spring. The ends of the rotative moving member 4 are thus held at the same positions as those in an initial state. The liquid housing container 1 is firmly fixed to the holder 11 by the engagement between the lower ends 18a and 19a of the guide grooves 18 and 19 and the opposite ends (locking portions) 4b1 and 4c1 of the rotative moving member 4. The installing operation is thus completed.
Now, with reference top
FIGS. 5A, 6A1, and 6A2 are diagrams showing a state observed before the liquid housing container 1 is connected to the head liquid supplying tube 13. In
FIGS. 5B, 6B1, and 6B2 shows that the engaging concave portions of the rotative moving member 4 have been engaged with the engaging projections 15 of the seal member with the rotative moving member 4 inserted around the liquid supplying tube. That is, in
1 shows how the seal member 14 operates in the state shown in
2 shows how the rotative moving member 4 operates in the state shown in
FIGS. 5C, 6C1, and 6C2 show that the liquid housing container 1 has been installed, that is, the liquid housing container 1 and the liquid supplying tube 13 have been connected together and fixed to the holder 11. At the position where the liquid housing container 1 is completely connected to the liquid supplying tube 13, the rotative moving member 4 functions as a member that fixes the housing container 1a. The opposite ends 4b1 and 4c1 of the rotative moving member 4 are rotated along the lower ends 18a1 and 19a1 of the guide grooves 18 and 19, respectively. As a result, the opposite ends 4b1 and 4c1 return to their initial positions (see
1 shows how the liquid supplying tube 13 and the seal member 14 operate after the liquid housing container 1 has been installed. In this case, the seal member 14 lowers along the liquid supplying tube 13, with the liquid introducing port 13a in the liquid supplying tube 13 in communication with the liquid housing container 1.
Now, with reference to
As previously described, the rotative moving member 4 has been engaged with and fixed to the opening 19a, formed in one 11S of the sides of the holder 11. In this case, as shown
To remove the container, the end 4c1 of the rotative moving member 4, projecting from the opening 19a, is moved leftward in the figure along the opening 19a, the lower end of the guide groove 19, against the urging force of the coil spring (not shown) (see
In the first embodiment, a position for an operation for removing the liquid housing container 1 is provided at a rear surface of the holder 11. However, another member can be used to move the removing position to above or front of the liquid housing container 1.
In the description of the above embodiment, by way of example, the rotative moving member 4 is rotatably movably held around the supplying port seal portion 3, projected from the housing container main body 1a. However, the rotative moving member 4 may be separable from the housing container main body 1a, and it is possible to individually perform the operation of rotating the rotative moving member 4 and the operation of installing the housing container main body 1a.
One of the functions of the rotative moving member 4 according to this embodiment is to reduce an increase in operating force required if sticking, liquid fixation, or the like occurs between the liquid supplying tube 13 and the seal member 14, to maintain a stable installing force. Accordingly, the rotative moving member 4 may be separable from the housing container main body 1a so that the housing container can be installed after the problem such as sticking or liquid fixation has been solved by solely using the rotative moving member 4.
First, as shown in
As described above, according to the first embodiment, as the housing container main body 1a is linearly moved, the rotative moving member 4 rotatably moves relative to the housing container main body 1a. The rotative moving force is thus transmitted to the seal portion. This eliminates the needs for rotating the housing container main body 1a and for a large space for an attaching and detaching operations. As a result, the size of the whole apparatus can be reduced. Further, the engaging portions (engaging projections 15) of the seal member 14 engage with the engaged portions (engaging concave portions) 5 of the liquid housing container 1 near the supplying port 2. Accordingly, the alignment near the supplying port 2 reduces the misalignment between the liquid supplying tube 13 and the supplying port 2. Moreover, the rotative moving member 4 on the liquid housing container 1 rotates the seal member 14 to enable the suppression of fixation of the seal portion caused by ink evaporation and of an increase in installation force caused by, for example, sticking of the seal member 14. Therefore, the liquid housing member can be easily and smoothly installed. Further, the holder 11 also functions as a guide for the liquid housing container 1. The holder 11 can hinder the liquid housing container 1 from being tilted or moved in the rotating direction during attachment or detachment.
Now, a second embodiment of the present invention will be described.
In the first embodiment, the angle through which the rotative moving member 4 can be rotated is determined by the distance from the rotating center (the center of the supplying port 2) of the rotative moving member 4 to the end 4a1, with which the opening 19a is engaged. That is, the angle through which the rotative moving member 4 can be rotated is determined by the length of the arm portion 4c and the width of the opening 19a (the width of the housing container main body 1a). Accordingly, if a larger rotating angle is required to accomplish a stable operation force, the length of the arm portion 4c of the rotative moving member 4 must be reduced or the width of the opening 19a must be increased. However, when the width of the holder 11 is set equal to or larger than that of the housing container main body 1a in order to increase the width of the housing 19a, this affects the operation of removing the housing container main body 1a, the head size, or the size of the housing container main body 1a. Accordingly, the increase in the width of the opening 19a is limited.
Thus, the second embodiment is intended to increase the angle through which the rotative moving member 4 can be rotated without the need for increasing the width of the holder 11.
To accomplish this object, the second embodiment has such a configuration as shown in
As shown in
By engaging the end 4c1 of the arm portion 4c with the opening 20 in the second side 1M, it is possible to increase the angle through which the rotative moving member 4 can be rotated without the need for increasing the width of the opening 20. However, the end 4c1 of the rotative moving member 4 is located inside the holder 11. It is difficult to operate the end 4c1 from front of the holder 11. Thus, a removing lever member 6 is rotatably movably provided on the bottom surface of the housing container main body 1a in such a way that one end 6a abuts against the end 4c1 of the rotative moving member 4, while the other end 6b is projected outward from the housing container main body 1a. This enables the other end 6b to engage with the opening 19, formed in the outer side 11S of the holder 11.
To remove the liquid housing container 1 from the holder 11, the end 6b of the lever member 6, which projects frontward from the opening 19a, is moved to rotate the rotative moving member 4 for removal as shown in
Now, a third embodiment of the present invention will be described with reference to
In the third embodiment, a protective member 7 is provided in order to protect the rotative moving member 4, disposed on the bottom surface of the liquid housing container 1. The rotative moving member 4 is provided on the bottom surface of the housing container main body 1a because it rotatably moves around the supplying port 2. Consequently, the rotative moving member 4 may be broken if it is inadvertently subjected to a large force exerted by an external source. Thus, in the third embodiment, the periphery of the rotative moving member 4 is covered with the protective member 7 to prevent an external force from being applied directly to the rotative moving member 4. The protective member 7 has a three-face structure with a right and left sides and a bottom surface and has substantially the same length as that of the housing container main body 1a. Thus, the protective member 7 covers the whole rotative moving member 4 except for the opposite ends 4b1 and 4c1. Further, the opposite ends 4b1 and 4c1 of the rotative moving member 4 project outward from respective openings formed in the opposite ends of the protective member 7. This enables the rotative moving member 4 to move rotatably and engage with the guide groove in the holder 11. Further, grooves 7a and 7b are formed at respective ends of the protective member 7 to avoid interference with the seal portion holding member of the holder 11. Thus, the rotative moving member 4 can be installed in the holder 11 with the protective member 7 installed.
In
(Another Shape of Rotative Moving Member)
The rotative moving member 4 is not limited to the ones shown in the above embodiments but may be shaped in a different manner.
The rotative moving members 4 shown in
In the rotative moving member 4 shown in
In the rotative moving member 4 shown in
(Another Configuration)
In the above embodiments, the rotative moving member attached to the housing container main body is engaged with the seal member or the rotative moving member is solely rotated. However, the rotative moving member may be pre-integrated with the seal member.
(Printing Apparatus)
In
A liquid ejected from an ejection port in the print head impacts a print medium 54 having its print surface regulated by a plate roller 55 so as to maintain a very small spacing between the print medium 54 and the print head 12. An image is thus formed on the print medium 54.
The print head 12 is appropriately supplied with an ejection signal from a data source (not shown) via a cable 52 and a terminal coupled to the cable 52, the ejection signal corresponding to image data. In the printing apparatus shown in the figure, one or more (in the figure, four) liquid housing containers 1 may be installed depending on the liquids used.
Further, in
The printing apparatus 50 shown in
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.
This application claims priority from Japanese Patent Application No. 2004-169111 filed Jun. 7, 2004, which is hereby incorporated by reference herein.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2004-169111 | Jun 2004 | JP | national |
