The present invention relates to a liquid injection apparatus including a recording head for injecting liquid.
Conventionally, a liquid injection apparatus injecting liquid by a desired method is known. For example, an ink-jet recording device serving as a liquid injection apparatus injects ink, which is liquid, from a plurality of nozzles formed in the recording head, thus forming an image such as a character on a recording surface.
To ensure a smooth operation of the recording head, a cap is pressed against a nozzle forming surface (a liquid injecting surface) of the recording head in order to define a sealed space. This prevents the recording head from becoming dry and from being contaminated by, for example, dusts.
For example, Japanese Laid-Open Patent Publication No. 2001-26113 discloses a liquid injection apparatus having a cap movable toward the recording head. To assure that the cap is reliably placed in tight contact with the nozzle forming surface, the cap is guided along a slanted surface of a guide extension in a sliding manner. The cap is thus positioned with high accuracy.
In this liquid injection apparatus, the recording head is reciprocated in a horizontal direction, while the cap is moved upward. However, for example, if the recording head is moved horizontally with the cap maintained in tight contact with the nozzle forming surface, the sealed space cannot be maintained. Further, the cap or recording head may be damaged. To avoid the problem, the liquid injection apparatus employs a mechanism for separating the cap from the recording head when the recording head moves.
The liquid injection apparatus starts to move the recording head for detecting the position of the recording head, for example, when the device is turned on. At this stage, the cap must be separated from the recording head. However, as above described, the recording head must be protected from dryness and contamination. Therefore, when the recording head is stopped, it is preferred that the cap maintain the liquid injecting surface of the recording head in a sealed state for avoiding the exposure to the ambient air.
In addition, for example, Japanese Laid-Open Patent Publication No. 2000-255075 discloses an inkjet recording device having a maintenance unit 1000, as illustrated in
With reference to
A contact piece 1090 is formed in the carriage 1040. A flag piece 1100 and a projection 1110 are formed in the cap unit 1030. When the carriage 1040 moves rightward as viewed in
If the carriage 1040 moves further rightward from the state of
This configuration regulates the position of the recording head 1050 to the position at which the cap 1060 reliably receives the ink discharged through flushing. Further, when capping is performed, the recording head 1050 and the cap member 1060 are reliably positioned relative with each other with high accuracy.
When flushing is performed, the recording head 1050 contacts the flushing guide extensions 1080, as illustrated in
In addition, in order assuredly form the clearance L for flushing, the maintenance unit 1000 must be provided with the flushing guide extensions 1080. This structure limits the layout of the maintenance unit 1000.
Accordingly, it is a first objective of the present invention to suppress deterioration of liquid to be injected. It is a second objective of the present invention to provide a liquid injection apparatus that operates silently.
To achieve the foregoing and other objectives and in accordance with the purpose of the present invention, the invention provides a liquid injection apparatus. The liquid injection apparatus has a liquid injecting head and a cap. The liquid injecting head includes a liquid injecting surface. The liquid injecting head is movable along a direction in which the surface injecting surface is extended. The cap is placed in tight contact with the liquid injecting surface for defining a sealed space. The liquid injecting head is allowed to move toward or away from a contact position at which the cap is placed in tight contact with the liquid injecting head. The cap is allowed to move along a direction crossing the liquid injecting surface toward or away from the contact position at which the cap is placed in tight contact with the liquid injecting surface. The cap is also allowed to move in a plane parallel to the liquid injecting surface.
The present invention provides another liquid injection apparatus. The liquid injection apparatus includes a liquid injecting head, a head moving mechanism, and a cap moving mechanism. The liquid injecting head has a liquid injecting surface. The cap is placed in tight contact with the liquid injecting surface for defining a sealed space. The head moving mechanism moves the liquid injecting head along a direction in which the liquid injecting surface is extended, such that the liquid injecting head is allowed to move toward or away from a contact position at which the cap is placed in tight contact with the liquid injecting head. The cap moving mechanism moves the cap toward or away from the contact position at which the cap is placed in tight contact with the liquid injecting surface. The cap moving mechanism includes a cap holding mechanism for holding the cap in a state slidable along a moving direction of the liquid injecting head and positioning the cap at the contact position.
The present invention provides another liquid injection apparatus. The liquid injection apparatus includes a liquid retaining portion, a liquid injecting head, a cap, and a maintenance unit. The liquid retaining portion retains liquid. The liquid injecting head injects the liquid supplied from the liquid retaining portion in a predetermined injecting zone. The cap seals the liquid injecting head outside the liquid injecting zone. The maintenance unit discharges the liquid injected by the liquid injecting head through the interior of the cap. The cap is placed at a reference position at which the cap is escaped from the path of the liquid injecting head when the liquid injecting head is moved in the injecting zone. The cap is placed at a set position at which the cap opposes the liquid injecting head when the liquid injecting head is moved outside the liquid injecting zone.
Other embodiments of the invention, together with advantages thereof, will become apparent by reference to the following description together with the drawings illustrating the principles of the present invention by way of example.
The characteristics of the present invention believed to be novel will become apparent in the attached claims. The invention, together with objectives and advantages thereof, may best be understood by reference to the following description of the presently preferred embodiments together with the accompanying drawings in which:
A first embodiment of the present invention will now be described with reference to
As shown in
The inkjet recording device 10 includes a platen 17 that is supported by the frame 10a and extends in the main scanning direction. A recording sheet P is supplied to the platen 17 by a non-illustrated paper supply mechanism having a paper supply motor 10b. A recording head 16 serving as a liquid injecting head is formed at the bottom of the carriage 12. The recording head 16 has a plurality of non-illustrated nozzles. The nozzles inject ink from the ink cartridge 11 to the recording paper P in a selective manner in accordance with printing data. An image such as a character is thus formed on a recording surface of the recording paper P. In this embodiment, the recording head 16 injects the ink by a pressurizing method involving displacement of a piezoelectric element. However, the ink injection of the recording head 16 may be performed by a pressurizing method involving heating and vaporization with a heater.
As shown in
To assure that a smooth recording operation is repeatedly performed, the head cleaning device 21 includes a timing mechanism that operates the cap mechanism 23 and the tube pump 25 at predetermined timings. That is, the flexible tube 24a and the sealed space defined by the cap 22 are depressurized through suction. The ink is thus drawn from the nozzles of the recording head 16 and is discharged to the discharged ink tray 26. In this manner, head cleaning is completed.
With reference to
As illustrated in
In the first embodiment, the rotary cam 27, the power transmitting gear 27b, and the springs 28a, 28b form a cap moving mechanism. The recording head 16 is reciprocated along a direction in which the nozzle forming surface 16a, which is in tight contact with the cap 22, is extended. In contrast, the cap 22 is lifted or lowered along the direction H such that the cap 22 is moved toward or away from the nozzle forming surface 16a.
As shown in
With reference to
The slider 31 supports the cap 22 such that the cap 22 is slidable in the main scanning direction (the extending direction of the nozzle forming surface 16a). The slider 31 includes a first cap stopper 31a and a second cap stopper 31b. Each of the stoppers 31a, 31b opposes an associated one of two perpendicular side surfaces of the cap 22. A spring 33, which serves an urging member, is arranged in the vicinity of the position at which the hypothetical plane along which the first cap stopper 31a is extended crosses the hypothetical plane along which the second cap stopper 31b is extended. The spring 33 urges the cap 22 toward the first and second cap stoppers 31a, 31b.
The first cap stopper 31a is engaged with the associated side of the cap 22, which is urged by the spring 33 to slide in the direction indicated by arrow A in the drawings (the direction in which the recording head 16 moves to the cleaning position). The position of the side of the cap 22 is thus determined. The second cap stopper 31b is engaged with the associated side of the cap 22, which is urged by the spring 33 to slide in the direction indicated by arrow B in the drawings, determining the position of the side of the cap 22.
The cap 22 is supported in a manner slidable in a range permitted by the slider 31 with respect to the main scanning direction. The cap 22 is positioned at a location at which the cap 22 is held in tight contact with the nozzle forming surface 16a of the recording head 16, as engaged with the cap stoppers 31a, 31b.
In the first embodiment, the slider 31, including the first and second cap stoppers 31a, 31b, the compression spring 32 and the spring 33, forms a cap holding mechanism. The first and second cap stoppers 31a, 31b also function as positioning portions. As illustrated in
A pair of resin head stoppers 31c, 31d are formed integrally with the slider 31. The head stoppers 31c, 31d are located at positions adjacent to the first and second cap stoppers 31a, 31b and outward with respect to the cap stoppers 31a, 31b, respectively. The first head stopper 31c is located outward with respect to a direction indicated by arrow A, as compared to the first cap stopper 31a. The second head stopper 31d is located outward with respect to a direction indicated by arrow B, as compared to the second cap stopper 31b. The head stoppers 31c, 31d extend upward with respect to the upper end 22a of the cap 22.
With reference to
When the slider 31 is held in a lifted state, the cap 22, which is positioned by the cap stoppers 31a, 31b, is placed in tight contact with the nozzle forming surface 16a. This arrangement defines a sealed space, which protects the recording head 16 from factors such as the ambient air. It also makes it possible to reliably execute a cleaning operation that includes, for example, drawing ink from the nozzles.
As the cap 22 approaches the recording head 16, the first and second head stoppers 31c, 31d are held in a state engaged with the side 12a and the rib 12c of the carriage 12, respectively. The recording head 16 is thus easily positioned at a standby position at which the recording head 16 is maintained when stopped.
More specifically, as illustrated in
For example, when the power source is turned on, the inkjet recording device 10 starts to execute a process for detecting the position of the recording head 16 in accordance with the flowchart of
More specifically, when the power source is turned on, the inkjet recording device 10 operates to rotate the motor 14 in a direction (indicated by arrow C in
The reverse rotation of the motor 14 moves the recording head 16 in a direction (indicated by arrow A in
In the first embodiment, the cap 22 is allowed to slide in accordance with the moving direction of the recording head 16. Further, since the moving range of the recording head 16 is limited to a relatively small range corresponding to the clearance X, the nozzle forming surface 16a of the recording head 16 is reliably maintained in the sealed state. This structure suppresses unnecessary separation of the cap 22 from the recording head 16. It is thus possible to suppress dryness or deterioration of ink, which is caused by the exposure of the nozzle recording surface 16a of the recording head 16 to the ambient air. As a result, the images are formed with the ink of an improved quality.
The stoppers 31a to 31d are formed integrally with the slider 31. The mechanism for either lifting or lowering the slider 31 is easily configured by the rotary cam 27, the power transmitting gear 27b, and the springs 28a, 28b. Further, the cap 22 is positioned easily by the spring 33. This structure lowers the production costs.
A second embodiment of the present invention will hereafter be described with reference to
As shown in
In the second embodiment, a zone in which the carriage 101 is reciprocated for injecting ink to the recording sheet P for printing an image corresponds to an injecting zone. The inkjet recording device 100 has a non-printing zone in which the nozzles are sealed when printing is suspended. A maintenance unit 110 is provided in the non-printing zone. The maintenance unit 110 performs maintenance work for the recording head 16 as needed, for maintaining the injecting performance of each nozzle in an optimal state.
With reference to
The recess formed by the cap 113 is divided into two sections. Each of the sections receives an associated one of absorbers 113a, 113b. A non-illustrated bottom of the cap 113 is connected with a discharged ink reservoir 115 through two tubes (not illustrated), each of which is connected with an associated one of the absorbers 113a, 113b, and a suction pump 114. The discharged ink reservoir 115 is formed below the platen 17, as shown in
If the suction pump 114 is actuated while a non-illustrated air valve maintains the recess of the cap 113 in a non-open state with the nozzles of the recording head 16 sealed by the cap 113, the ink is drawn from the nozzles of the recording head 16. The ink is introduced through the tubes and then discharged to the discharged ink reservoir 115. Further, if the suction pump 114 is actuated with the recess of the cap 113 maintained in an open state by the air valve and without sealing the nozzles of the recording head 16 by the cap 113, the ink is drawn from the cap 113 through the tubes and then discharged to the discharged ink reservoir 115.
Therefore, in this structure, if the ink cartridge 102 reserves pigment ink and reactant ink, the two types of ink are separately absorbed by the absorbers 113a, 113b and separately discharged to the discharged ink reservoir 115.
As illustrated in
The configuration of the maintenance unit 110 will now be explained with reference to
As shown in
As aforementioned, the first spring member SP1 secures the slider 112 to the casing main body 103. The slider 112 is thus urged in the leftward direction (−A) with respect to the casing main body 103. Therefore, when the slider 112 is free from other force, a wall of the insert recess 117 is held in a state abutted by the right side wall of the slider guide 116 in the casing main body 103 (a reference position), as illustrated in
With reference to
As illustrated in
The cap 113 is urged in the upward direction (+H) by the second spring member SP2. Meanwhile, the upward movement of the cap 113 (in direction +H) is limited by the second and third support bars 120, 121 and the positioning bar 122. Thus, normally, the cap 113 is located at a position most spaced from the slider 112 in the upward direction (+H). The cap 113 is moved downward (in direction −H) if urged downward (in direction −H).
With reference to
As shown in
With reference to
Further, if the slider 112 is moved rightward (in direction +A) from the reference position, the cap 113 secured to the slider 112 is urged by the third spring member SP3 in the forward direction (+B). This moves the positioning bar 122 along a slope 128 of the projection 126 in the rightward and forward direction (the combined direction of +A and +B). As shown in
For example, if the recording head 16 contacts the contact portion 129 of the slider 112 to urge the slider 112 rightward (in direction +A), the slider 112 moves in the rightward direction (+A). In accordance with the movement of the slider 112, the cap 113 is moved to the set position. The extension T of the cap 113 is thus moved forward (in direction +B) and contacts the recording head 16. The set position corresponds to the position at which the cap 113 directly opposes the nozzles of the recording head 16. The reference position corresponds to the position at which the cap 113 is retreated from the path of the recording head 16 along the main scanning direction.
The dimension of the guide groove 125 of the slider 112 is approximately 1.2 times as large as the diameter of the positioning bar 122 of the cap 113. It is thus possible to suppress deterioration of the positioning bar 122, which is otherwise caused by the contact between the positioning bar 122 and the wall of the guide groove 125. It is also possible to avoid friction between the positioning bar 122 and the wall of the guide groove 125, which hampers the movement of the cap 113 in the forward or rearward directions.
Next, the configuration of the drive mechanism for the slider 112 will be explained with reference to
As shown in
As illustrated in
A cam mechanism 140 is accommodated in the casing main body 103 and serves as a drive mechanism located below the slider 112. The cam mechanism 140 includes a shaft 141, a gear 142, and two cam portions 143, 144. The gear 142 is secured to the shaft 141. The cam portions 143, 144 are also secured to the shaft 141 with the gear 142 located between the cam portions 143, 144. When the gear 142 is driven to rotate, the cam portions 143, 144 are rotated in the same direction.
One of the opposing ends of the shaft 141 is fitted in a support hole 145 (
When the cam portions 143, 144 are rotated, each of the slide shafts 138, 139 slides along the associated one of the slide grooves 146, 147. In this state, each of the contact shafts U1, U2 slidably contacts and is supported by the associated one of the sides 143a, 144a of the cam portions 143, 144. In accordance with the rotation of the cam portions 143, 144, the interval between the shaft 141 and each contact shaft U1, U2 is shortened or lengthened. Further, in accordance with the position of the shaft 141 and the position of each shaft U1, U2 relative with each other, the shaft 132 of the slider 112 is guided along the guide groove 134. This structure enables the slider 112 to move in the height directions (+H and −H) with respect to the casing main body 103.
A non-illustrated drive mechanism transmits the drive force of a non-illustrated drive motor, which is capable of rotating in positive or negative directions, to the gear 142 of the cam mechanism 140. For example, if each of the slide grooves 146, 147 of the cam portions 143, 144 is located relative to the associated one of the slide shafts 138, 139 as indicated in
In contrast, if the drive motor is rotated in the negative direction with each slide groove 146, 147 located relative to the associated slide shaft 138, 139 as indicated in
The distance d1 is smaller than the distance d2 and the distance d2 is smaller than the distance d3: d1<d2<23. Therefore, in the second embodiment, as held in the state of
In the second embodiment, the state of
When the slider 112 is held in the standby state, the wiper W is received in the casing main body 103. When the slider 112 switches to the flushing state, the wiper W is moved out of the casing main body 103 and sent to a position at which the slider 112 is allowed to contact the recording head 16.
The operation of the maintenance unit 110, configured as described above, will hereafter be explained, with reference to
As illustrated in
To perform blank injection of ink from the nozzles of the recording head 16 toward the cap 113, which is called flushing, the carriage 101 is moved to the non-printing zone. The recording head 16 is thus placed in contact with the contact portion 129 of the slider 112. In this state, the slider 112 is located at the set position, as shown in
When the recording head 16 is placed in contact with the contact portion 129 of the slider 112, the slider 112 is switched from the standby state to the flushing state. Further, the wiper W is moved out of the case 103 to the position at which the wiper W is allowed to contact the recording head 16. The wiper W wipes ink from the nozzle forming surface 16a of the recording head 16, when the recording head 16 passes over the wiper W for proceeding to the contact portion 129 of the slider 112. When the slider 112 is placed in the flushing state, the drive motor is stopped, such that the flushing state illustrated in
To seal the recording head 16 in the state of
The second embodiment has the following advantages.
When the carriage 101 is moved to the non-printing zone, the extension T is not located in the path of the recording head 16. The carriage 101 is thus prevented from contacting the extension T. This structure avoids noise generation due to an impact caused by the contact between the carriage 101 and the extension T. The inkjet recording device 100 is thus operated silently. Further, since the cap 113 is moved forward (in direction +B), the extension T is allowed to contact the recording head 16 at the set position. The cap 113 is thus accurately placed and held at the position opposing the recording head 16. Therefore, if the ink cartridge 102 retains pigment ink and reactant ink, the cap 113 reliably receives the ink discharged from the nozzles, allows the absorbers 113a, 113b to absorb the ink, and enables the ink to be discharged to the discharged ink reservoir 115.
When held in the flushing state, the cap 113, which is mounted on the slider 112, opposes the recording head 16 as spaced from the recording head 16 by the clearance L1. Thus, the extension T can be formed relatively short, as compared to the flushing guide extension 1080 of
In the second embodiment, when the slider 112 is moved, the cap 113 is allowed to move forward (in direction +B). Further, the slider 112 is allowed to move along the height direction by means of the cam mechanism 140. This structure saves the space needed for moving the maintenance unit 110 to the position opposed to the recording head 16, as compared to the prior-art structure of
The present invention is not limited to the illustrated embodiments but may be varied in the following forms.
In the embodiment of
In the embodiment of
The present invention may be embodied as a liquid injection apparatus other than the inkjet recording device 10 of
As is clear to those skilled in the art, the present examples and embodiments are to be considered as illustrative and not restrictive and the invention is not to be limited to the details given herein, but may be modified within the scope and equivalence of the appended claims, without departing from the scope of the present invention.
Number | Date | Country | Kind |
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2003-101871 | Apr 2003 | JP | national |
2003-343748 | Oct 2003 | JP | national |
Number | Date | Country |
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2000-255075 | Sep 2000 | JP |
2001-26113 | Jan 2001 | JP |
Number | Date | Country | |
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20040263559 A1 | Dec 2004 | US |