JP2005199526A - Liquid jetting apparatus and method for driving liquid jetting apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid jetting apparatus capable of preventing an excess suction during cleaning from being generated, performing lifetime extension of an ink cartridge, and realizing sound reduction, and a method for driving the liquid jetting apparatus. <P>SOLUTION: When a cleaning action is performed for a printer 1, a solenoid valve of an opening device 22 is made into an OFF condition to make a communicated condition, and a gear pump GP is driven. In this instance, a check valve 14 is easily made into a communicated condition, and fluctuation of a suction amount of an ink is suppressed to suppress consumption of the ink, and loading of the gear pump GP is decreased to reduce noises. Waste ink and air sucked from a cap member 12 are made to successively flow in the cap member 12, a tube T2, the gear pump GP, a tube T3, the check valve 14 and a tube T4, and then, to flow into an ink cartridge 9. Furthermore, they are made to flow into an ink cartridge 10 through a tube T6 as a compressed air. Decrease in the pressure of this compressed air is reduced by the check valve 14. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a liquid ejecting apparatus and a method for driving the liquid ejecting apparatus.

  Conventionally, an ink jet recording apparatus is widely known as one of liquid ejecting apparatuses. This ink jet recording apparatus includes a so-called off-carriage type in which an ink container provided in an ink cartridge as a liquid container is connected to a recording head via an ink supply tube. In this off-carriage type, the ink container is pressurized by sending pressurized air into the ink cartridge by a pump or the like. Under this pressure application, the ink stored in the ink container is pumped toward the recording head via the ink supply tube, whereby the ink is supplied to the recording head. Then, the supplied ink is ejected onto the recording paper as ink droplets from the nozzle openings of the recording head for recording.

  Also, in general, in an ink jet recording apparatus, in order to reduce ink ejection defects, bubbles and thickened ink are discharged from the nozzle openings of the recording head and then discarded in a waste ink tank by appropriate cleaning. It was.

  Various off-carriage type ink jet recording apparatuses having such a waste ink tank and an ink cartridge integrally formed have been proposed. (For example, Patent Document 1).

  As shown in FIG. 8, the ink jet recording apparatus 100 described in Patent Document 1 includes an ink tank 102 that stores an ink bag 101. The ink bag 101 is connected to the recording head 105 via an ink supply pipe 104 connected to the ink supply port 103 of the ink tank 102. Further, the ink jet recording apparatus 100 is provided with a cap 106 that receives the waste ink discharged from the recording head 105. The cap 106 is connected to the pressure port 109 of the ink tank 102 via the ink recovery pipe 107 and the pump 108. A valve 112 for opening the ink tank 102 as appropriate and a pressure sensor 113 for detecting the pressure in the ink tank 102 are connected to the discharge port 110 of the ink tank 102 through a flow path 111. Furthermore, a stopper 114 that blocks or releases the flow of ink in the ink supply pipe 104 is provided in the middle of the ink supply pipe 104.

  In the ink jet recording apparatus 100, when the pump 108 is driven in a state where the stopper 114 is opened, waste ink and air are sent from the cap 106 to the ink tank 102 via the ink recovery pipe 107. ing. As a result, the pressure in the ink tank 102 rises, the ink bag 101 is crushed, and ink is supplied to the recording head 1 via the ink supply pipe 104.

In the ink jet recording apparatus 100 formed in this way, when performing the recovery operation, the ink supply pipe 114 is shut off by the stopper 114 and the pump 108 is operated. When the ink tank 102 reaches a predetermined pressure, the ink supply pipe 114 is opened. As a result, ink flows into the recording head 105 all at once, and the ink and bubbles in the ink flow out from the nozzle portion of the recording head 105 to perform the pressure recovery operation.
JP 2001-162838 A

In recent years, there has been a demand for downsizing of liquid ejecting apparatuses. And a gear pump attracts attention as a pump which can realize this miniaturization.
However, when the gear pump is employed in the ink jet recording apparatus 100 of Patent Document 1, the ink tank 102 is filled with waste ink and air, and the upstream side pressure and downstream side of the ink supply pipe 107 with the gear pump as a boundary. When the pressure difference between the two sides increases, the flow rate of waste ink and air from the upstream side to the downstream side may decrease.

  In order to ensure a sufficient flow rate when the pressure difference between the upstream and downstream pressures increases, driving the gear pump at high speed to increase the suction capacity also increases the load on the gear pump and generates noise. There was a fear.

  In general, the gear pump has a characteristic that the suction ability is improved when the liquid is filled therein. Therefore, during the recovery operation, in order to obtain a sufficient cleaning effect, it is necessary to continue to rotate the gear pump even from a state where the ink is drawn into the gear pump and the suction performance is improved. On the other hand, as described above, when the pressure difference between the upstream pressure and the downstream pressure of the ink supply pipe 107 at the boundary of the gear pump is large, the flow rate decreases and the liquid is drawn into the gear pump. It takes longer time than the case where the pressure difference is small.

For this reason, it is necessary to set the rotation time of the gear pump for a long time so that the gear pump can rotate even when the ink is drawn into the gear pump and the suction performance is improved.
However, in this case, if the suction is performed with the gear pump when the pressure difference between the upstream side and the downstream side of the ink supply pipe 107 at the boundary of the gear pump is small, the inside of the gear pump is quickly completed. Ink is drawn into the gear pump, and the suction capacity of the gear pump is improved. As a result, the gear pump will rotate for a long time with the suction capability improved, and a large amount of ink will be sucked into the amount required for the head recovery operation, thereby shortening the life of the ink cartridge. There was a risk of it.

  The present invention has been made in order to solve the above-described problems, and can prevent excessive suction during cleaning, extend the life of the ink cartridge, and realize a quiet operation. It is an object to provide an ejection device and a method for driving a liquid ejection device.

  The liquid ejecting apparatus of the present invention includes a liquid container that stores liquid, a liquid ejecting head that ejects the liquid supplied from the liquid container, a cap member that receives waste liquid discharged from the liquid ejecting head, A liquid ejecting apparatus comprising: a waste liquid tank for storing the waste liquid; and suction means for sucking the waste liquid from the cap member and introducing the waste liquid into the waste liquid tank, wherein the inside of the waste liquid tank is opened to the atmosphere. An opening means was provided.

  According to this, for example, when the waste liquid is introduced into the waste liquid tank via the suction means, if the pressure difference between the cap member side and the waste liquid tank side is large, the waste liquid is supplied to the waste liquid tank. However, the pressure difference can be reduced by opening the inside of the waste liquid tank by the opening means and making the pressure on the waste liquid tank side equal to the atmospheric pressure. As a result, when the suction means is used for cleaning, the discharge side can be used only in the atmospheric pressure state, and the variation in the suction amount can be reduced, so that the suction amount can be prevented from being excessively increased. . Further, since the waste liquid can easily flow to the waste liquid tank, the suction capability of the suction means is not increased, the load on the suction means can be reduced, and the noise can be reduced.

  The waste liquid tank of the liquid ejecting apparatus stores the waste liquid and also stores the liquid container, and the suction means sucks the waste liquid from the cap member and introduces the waste liquid into the waste liquid tank. In addition, air is sucked from the cap member to pressurize the liquid container, and the liquid is supplied to the liquid ejecting head.

  According to this, for example, when the waste liquid is introduced into the waste liquid tank via the suction means, the waste liquid tank is filled with air, and the pressure difference between the pressure on the cap member side and the waste liquid tank side becomes large. In this case, the flow of the waste liquid to the waste liquid tank is reduced, but the air can be released to the atmosphere by opening the waste liquid tank by the opening means. As a result, the pressure on the waste liquid tank side can be made equal to the atmospheric pressure to reduce this pressure difference, and when the suction means is used for cleaning, it can be used only when the discharge side is at atmospheric pressure. Since the variation in the suction amount can be reduced, it is possible to prevent the suction amount from being excessively increased. Further, since the waste liquid can easily flow to the waste liquid tank, the suction capability of the suction means is not increased, the load on the suction means can be reduced, and the noise can be reduced. In addition, since the liquid container is pressurized using the suction means, it is not necessary to provide a pump for pressurization, and the apparatus can be configured in a small size and at low cost.

The opening means of the liquid ejecting apparatus is a solenoid valve that opens the waste liquid tank when in a communicating state.
According to this, the pressure difference between the cap member side and the waste liquid tank side can be reduced by opening the waste liquid tank and making the pressure on the waste liquid tank side equal to the atmospheric pressure by connecting the solenoid valve. As a result, when the suction means is used for cleaning, the discharge side can be used only in the atmospheric pressure state, and the variation in the suction amount can be reduced, so that the suction amount can be prevented from being excessively increased. . In addition, since the waste liquid can easily flow into the waste liquid tank, an increase in the load on the suction means can be reduced and noise can be reduced without increasing the suction capability of the suction means. In addition, since it is a solenoid valve, it is possible to control the communication state and non-communication state only by energization, and there is no need to provide a drive motor, position sensor, etc., so the liquid ejecting device is small and low-cost. I can do it.

  The method for driving a liquid ejecting apparatus according to the present invention includes a liquid container that stores liquid, a liquid ejecting head that ejects the liquid supplied from the liquid container, and a cap that receives waste liquid discharged from the liquid ejecting head. A liquid ejecting apparatus drive method comprising: a member, a waste liquid tank that stores the waste liquid, and a suction unit that sucks the waste liquid from the cap member and introduces the waste liquid into the waste liquid tank. When the waste liquid is sucked, the waste liquid tank is opened to the atmosphere.

  According to this, for example, when the pressure difference between the pressure on the cap member side and the waste liquid tank side is large, the flow of this waste liquid is reduced, but the inside of the waste liquid tank is opened to reduce the pressure on the waste liquid tank side. This pressure difference can be reduced by being equivalent to the atmospheric pressure. As a result, when the suction means is used for cleaning, the discharge side can be used only in the atmospheric pressure state, and the variation in the suction amount can be reduced, so that the suction amount can be prevented from being excessively increased. . Further, since the waste liquid can easily flow to the waste liquid tank, the suction capability of the suction means is not increased, the load on the suction means can be reduced, and the noise can be reduced.

  In the method for driving the liquid ejecting apparatus, the waste liquid tank stores the waste liquid and stores the liquid container, and the suction unit sucks the waste liquid from the cap member to remove the waste liquid. In addition to being introduced into the waste liquid tank, air is sucked from the cap member to pressurize the liquid container, and the liquid is supplied to the liquid ejecting head.

  According to this, for example, when the waste liquid tank is filled with air and the pressure difference between the cap member side and the waste liquid tank side is large, the flow of this waste liquid is reduced. By opening, this air can be released to the atmosphere. As a result, the pressure on the waste liquid tank side can be made equal to the atmospheric pressure, and the pressure difference can be reduced. When the suction means is used for cleaning, the discharge side can be used only in the atmospheric pressure state, Since the variation in the suction amount can be reduced, it is possible to prevent the suction amount from being excessively increased. Further, since the waste liquid can easily flow to the waste liquid tank, the suction capability of the suction means is not increased, the load on the suction means can be reduced, and the noise can be reduced.

Hereinafter, an embodiment embodying the present invention will be described with reference to FIGS.
FIG. 1 is a perspective view for explaining an outline of the printer of the present embodiment. FIG. 2 is a block diagram for explaining an ink supply system to the recording head of this embodiment.

  As shown in FIG. 1, a printer 1 as a liquid ejecting apparatus includes a substantially rectangular frame 2. A paper feed tray 3 is provided on the upper surface of the frame 2, and a paper discharge tray 4 is provided on the front surface of the frame 2. The paper feed tray 3 and the paper discharge tray 4 are configured to be foldable and accommodated with respect to the frame 2 by a hinge structure (not shown).

  A platen 5 is disposed in the longitudinal direction of the frame 2, and recording paper inserted into the frame 2 from the paper feed tray 3 is fed onto the platen 5 by a paper feed mechanism (not shown). It has become so. The fed recording sheet is discharged from the discharge tray 4 to the outside of the frame 2.

  A guide member 6 is installed in the frame 2 so as to be parallel to the platen 5. A carriage 7 that is movable along the guide member 6 is inserted into and supported by the guide member 6. A carriage motor (not shown) is attached to the frame 2, and the carriage 7 is connected to the carriage 7 via a timing belt (not shown) hung on a pair of pulleys (not shown). Has been. With this configuration, when the carriage motor is driven, the driving force is transmitted to the carriage 7 via the timing belt. In response to this driving force, the carriage 7 is guided by the guide member 6 and reciprocates in parallel (main scanning direction) with the platen 5.

  On the other hand, a recording head 8 as a liquid ejecting head is provided on the lower surface of the carriage 7 (the surface facing the platen 5). The recording head 8 has a nozzle forming surface 8a (see FIG. 2) so as to face the recording paper, and n (n is a natural number) nozzles N (n is a natural number) per row. 6 rows of nozzle rows (not shown) are formed. In the present embodiment, for convenience of explanation, six nozzle rows composed of n nozzles N per row are formed, but this is not restrictive, and the number of nozzles N and the number of nozzle rows per row may be changed as appropriate. Also good.

  As will be described later, the recording head 8 has colors corresponding to the respective nozzles (black in the present embodiment) from the first and second ink cartridges 9 and 10 as liquid containers provided in the frame 2. , Cyan, magenta, yellow, light cyan, light magenta) ink is supplied. The ink flowing into the recording head 8 is pressurized by the piezoelectric element 8b (see FIG. 2), and is ejected as an ink droplet from the nozzle N of the recording head 8, thereby forming dots. That is, black, cyan, magenta, yellow, light cyan, and light magenta, which are corresponding colors, are ejected from each nozzle N formed in the recording head 8.

  In the printer 1, an area for printing by ejecting ink droplets onto a recording sheet while reciprocating the carriage 7 is used as a printing area. Further, the printer 1 is provided with a non-printing area for sealing the nozzle N during non-printing, and a cap holder 11 is provided in the non-printing area as shown in FIG.

  The cap holder 11 is provided with a flexible cap member 12 so as to face the nozzle forming surface 8 a of the recording head 8. The cap holder 11 seals each nozzle N by bringing the cap member 12 into close contact with the nozzle forming surface 8a of the recording head 8 via a drive mechanism (not shown). Further, as shown in FIG. 2, the cap member 12 has first and second communication ports 12a, 12b (see FIG. 2) communicating with the inside of the cap member 12 at the bottom thereof. A cap opening valve 13 is connected to the mouth 12a outside the cap holder 11 via a tube T1. The cap opening valve 13 appropriately opens a space formed by bringing the cap member 12 and the nozzle forming surface 8a into close contact with each other. Further, the second communication port 12b is connected to a suction port (not shown) of the gear pump GP via the tube T2. The gear pump GP includes gears G1 and G2. When a driving force is transmitted from a driving motor (not shown), the gears G1 and G2 are rotationally driven to apply a negative pressure to the cap member 12. . That is, when the cap opening valve 13 is closed and the nozzle forming surface 8a is sealed by the cap member 12, the gear pump GP is driven to negatively affect the nozzle N on the nozzle forming surface 8a. It can be cleaned under pressure.

  A check valve 14 is connected to a discharge port (not shown) of the gear pump GP via a tube T3, and the fluid introduction member 15 of the first ink cartridge 9 is connected to the check valve 14 via a tube T4. ing.

  The first ink cartridge 9 accommodates an ink pack B that stores black ink and an ink absorber 17 that absorbs ink in each storage section partitioned by the partition plate 16. The ink pack B is connected to the recording head 8 of the carriage 7 through a tube T5. The ink absorber 17 is a porous material having water absorption, such as sponge.

  With this configuration, waste ink and air sucked from the cap member 12 by the gear pump GP flows into the first ink cartridge 9 from the fluid introduction member 15. At this time, the waste ink flowing into the first ink cartridge 9 is absorbed by the ink absorber 17. Further, as will be described later, the check valve 14 prevents backflow of waste ink and air to the cap member 12 side.

  An air introduction member 19 of the second ink cartridge 10 is connected to the air lead-out member 18 of the first ink cartridge 9 via a tube T6, and the first ink cartridge 9 and the second ink cartridge 9 are connected. The cartridges 10 communicate with each other. The second ink cartridge 10 stores ink packs C, M, Y, LC, and LM that respectively store cyan, magenta, yellow, light cyan, and light magenta inks in each storage section partitioned by the partition plate 20. Contained. The ink packs C, M, Y, LC, and LM are connected to the recording head 8 of the carriage 7 via tubes T7 to T11, respectively. An opening device 22 is connected to the air outlet member 21 of the second ink cartridge 10 via a tube T12. As will be described later, the opening device 22 is for opening the inside of the second ink cartridge 10 as appropriate.

  With this configuration, when the gear pump GP is driven, waste ink and air are sucked from the cap member 12, and the waste ink and air are collected from the cap member 12 → tube T2 → gear pump GP → tube T3 → check valve 14 → After flowing through the tube T4 in order, it flows into the first ink cartridge 9. At this time, waste ink that flows into the first ink cartridge 9 is absorbed by the ink absorber 17 described above, and therefore, air that has flowed into the first ink cartridge 9 (hereinafter referred to as pressurized air). ) Only flows. The pressurized air flows from the first ink cartridge 9 into the second ink cartridge 10 through the tube T6 and is then held by the opening device 22 connected to the tube T12. .

  That is, since the air pressures in the first and second ink cartridges 9 and 10 are always equal and without deviation, when the gear pump GP is driven, the respective ink packs in both the first and second ink cartridges 9 and 10 are driven. B, C, M, Y, LC, and LM are pressurized by the above-described pressurized air. As a result, the ink stored in the ink packs B, C, M, Y, LC, and LM is pumped to the recording head 8 of the carriage 7, respectively.

  That is, in the printer 1 of the present embodiment, the gear pump GP also serves as a cleaning pump that applies a negative pressure to the cap member 12 and a pressurizing pump that pressurizes each ink pack B, C, M, Y, LC, and LM. It is like that. When the gear pump GP is driven, negative pressure is applied to the cap member 12 to suck waste ink and air, and the ink packs B, C, M, Y, LC, and LM are pressurized, and the ink is applied to the recording head 8. Is supposed to be pumped.

Next, the configuration of the check valve 14 will be described with reference to FIGS. 3 and 4 are cross-sectional views for explaining the configuration of the check valve 14 of the present embodiment.
As shown in FIG. 3, the check valve 14 includes a main body case 30, a diaphragm portion 31, a support member 32, and a spring member 33. The main body case 30 includes an upper case 30a and a lower case 30b, and an upstream valve chamber 34 is annularly recessed in the upper case 30a. Moreover, the downstream side valve chamber 35 is recessedly provided in the lower case 30b in a funnel shape. A valve chamber 36 is formed in the main body case 30 by attaching the upper case 30a to the lower case 30b.

  The main body case 30 of the check valve 14 is formed with an attachment port (not shown) for attaching the tube T3 and an attachment port 37 for attaching the tube T4. An attachment port (not shown) for attaching the tube T3 communicates with the upstream valve chamber 34 via a first flow path 38 formed through the main body case 30 (upper case 30a). . Further, the attachment port 37 for attaching the tube T4 communicates with the downstream valve chamber 35 via a second flow path 39 penetratingly formed in the main body case 30 (lower case 30b). With this configuration, waste ink and air sent from the gear pump GP are passed through the tube T3 and the first flow path 38 in the valve chamber 36 (upstream valve chamber 34 and downstream valve chamber 35). Inflow. Further, the ink flows out from the valve chamber 36 to the ink cartridge 9 through the second flow path 39 and the tube T4.

On the other hand, the diaphragm portion 31 is made of a flexible member such as rubber and is formed in a disc shape. When the check valve 14 is formed, the diaphragm portion 31 is accommodated in the valve chamber 36 with the outer edge portion 40 held between the upper cases 30a and 30b of the main body case 30 and fixed. The With this configuration, the diaphragm portion 31 defines the upstream side valve chamber 34 and the downstream side valve chamber 35 in the valve chamber 36, and the central portion thereof is in the vertical direction (upstream and downstream) shown in FIG. It is possible to reciprocate in the downstream valve chambers 34 and 35 direction. A communication hole 41 is formed at the center of the diaphragm portion 31 so as to penetrate the diaphragm portion 31. The communication hole 41 allows the upstream and downstream valve chambers 34 and 35 to communicate with each other, and an annular cap portion 42 is formed on the peripheral edge (on the upstream valve chamber 34 side). A cylindrical abutting portion 43 is formed to project from the upper case 30a so as to face the cap portion 42 directly. The abutting portion 43 abuts on and closely contacts the cap portion 42 to bring the communication hole 41 into a non-communication state. As described above, the upstream valve chamber 34 is recessed in the upper case 30a. By being provided, it is formed to protrude in a cylindrical shape. With this configuration, when the diaphragm portion 31 is bent downward (downstream valve chamber 35 direction) and the cap portion 42 is separated from the contact portion 43, the upstream and downstream valves The chambers 34 and 35 are in communication. When the diaphragm portion 31 is bent upward (in the upstream valve chamber 34 direction) and the cap portion 42 is in contact with the contact portion 43, the upstream valve chamber 34 and the downstream valve chamber 35 are It becomes a non-communication state.

  Further, a support member 32 formed in a cylindrical shape from the downstream valve chamber 35 side is fitted into the communication hole 41 of the diaphragm portion 31, and is integrated with the diaphragm portion 31. As will be described later, the support member 32 receives and urges the urging force from the spring member 33 to support and urge the diaphragm portion 31 upward from the downstream valve chamber 35 side (upstream valve chamber 34 direction). An inner hole 44 is formed in the inner diameter portion. As described above, the inner hole 44 communicates with the communication hole 41 by fitting the support member 32 into the communication hole 41 of the diaphragm portion 31 and integrating the support member 32. Further, a convex portion 32 a is formed on the outer surface of the support member 32, and the convex portion 32 a comes into contact with the diaphragm portion 31 on the upper side (upstream valve chamber 34 side). Thus, the support member 32 is positioned when fitted to the diaphragm portion 31.

  On the other hand, a circular groove 45 is recessed at the bottom of the downstream valve chamber 35 at a position facing the support member 32. The groove 45 is supported by fitting the spring member 33. The spring member 33 is disposed in the downstream valve chamber 35 by being fitted into the groove 45 and fitted into the outer surface of the support member 32 and abutting against the convex portion 32a. Yes. As described above, the spring member 33 biases the diaphragm portion 31 upward (upstream valve chamber 34 side) via the support member 32. The spring member 33 biases the diaphragm portion 31 in a state where the pressure difference between the upstream and downstream valve chambers 34 and 35 is equal to or less than a preset reference value, and the cap portion of the diaphragm portion 31 42 is set to contact the contact portion 43. Further, the spring member 33 has an upstream valve chamber 34 that is transmitted via the diaphragm portion 31 in a state where the pressure difference in the upstream and downstream valve chambers 34 and 35 is equal to or greater than a predetermined reference value. It is set so as to bend in the downward direction (downstream valve chamber 35 direction) in response to the pressure.

With this configuration, when the pressure difference in the upstream and downstream valve chambers 34 and 35 of the check valve 14 is equal to or less than a preset reference value, as shown in FIG. The cap portion 42 of 31 is in contact with the contact portion 43. At this time, the check valve 14 places the upstream and downstream valve chambers 34 and 35 in a non-communication state so that the waste ink and the air do not flow. When waste ink and air flow from the gear pump GP into the check valve 14 from this state, the waste ink flows into the upstream valve chamber 34 as shown in FIG. 4A. As a result, the upstream valve chamber 34 is filled with waste ink. Further, when the pressure difference between the upstream and downstream valve chambers 34 and 35 increases and becomes a state equal to or higher than a preset reference value, the check valve 14 has a cap portion 42 as shown in FIG. Is separated from the contact portion 43. As a result, the check valve 14 is connected to the upstream and downstream valve chambers 34 and 3.
The waste ink and the air are made to flow with 5 being in a communicating state. At this time, the waste ink and air flowing into the check valve 14 from the gear pump GP via the tube T3 are the first flow path 38 → the upstream valve chamber 34 → the communication hole 41 → the inner hole 44 → the downstream valve chamber 35. After flowing in the order of the second flow path 39 → the tube T 4, it flows out to the first ink cartridge 9. Then, as shown in FIG. 4C, when the operation of the pump is stopped and the flow of the waste ink and the air to the first flow path 38 is stopped, the pressure in the upstream side valve chamber 34 is reduced, and the downstream side The pressure difference from the side valve chamber 35 is equal to or less than the reference value. At this time, as described above, the diaphragm portion 31 is urged upward (in the upstream valve chamber 34 direction) by the spring member 33 and is directed upward in the same direction by the waste ink filled in the downstream valve chamber 35. Pressed. As a result, the cap part 42 of the diaphragm part 31 again comes into contact with the contact part 43, and the upstream and downstream valve chambers 34 and 35 are again brought into a non-communication state, thereby preventing the waste ink and the air from flowing. Thus, the waste ink and air are prevented from flowing backward from the downstream valve chamber 35 toward the upstream valve chamber 34, and the waste ink and air are prevented from flowing back to the gear pump GP.

  With this configuration, the check valve 14 is in a communication state only when waste ink and air that can make the pressure difference between the upstream and downstream valve chambers 34 and 35 equal to or greater than the reference value flow. Thus, the waste ink and air are caused to flow to the first ink cartridge 9. That is, in the printer 1 of the present embodiment, waste ink and air from the gear pump GP flow into the first ink cartridge 9 through the check valve 14 and further flow into the second ink cartridge 10 as pressurized air. Thus, pressurized air that satisfies the reference pressure is supplied to the first and second ink cartridges 9 and 10. The reference pressure is a preset reference value for suitably pressurizing each ink pack B, C, M, Y, LC, LM.

  As a result, even if the pressure pumped air flows through the tube T3 and the pressure is lost by the gear pump GP, or even if the suction capacity of the gear pump GP is low, the pressurized air that satisfies the reference pressure is The ink packs B, C, M, Y, LC, and LM in the first and second ink cartridges 9 and 10 can be suitably pressurized. Further, as described above, the waste ink and air that flow to the first ink cartridge 9 via the check valve 14 are prevented from backflowing, so that the recording head 8 can be operated like the conventional liquid ejecting apparatus described above. Staining can be reduced. Still further, a decrease in the pressure of the pressurized air flowing in the first and second ink cartridges 9 and 10 can be reduced.

Next, the configuration of the above-described opening device 22 will be described with reference to FIGS. 5-7 is sectional drawing for demonstrating the structure of the opening | release apparatus 22 of this embodiment.
As shown in FIG. 5, the opening device 22 includes a main body case 50, a release valve 51 and a solenoid valve 52 housed in the main body case 50.

Specifically, the main body case 50 includes a first case 50a, a second case 50b, and a third case 50c, and a downstream air chamber 53 is recessed in the first case 50a. An upstream air chamber 54 is recessed in the second case 50b. Then, by attaching the first case 50 a to the second case 50 b, the first air chamber 55 is formed from the upstream and downstream air chambers 54 and 53 in the main body case 50. An attachment port 56 for attaching the tube T12 is formed in the second case 50b of the main body case 50. The attachment port 56 communicates with the first air chamber 55 (upstream air chamber 54) via a flow path 57 formed through the second case 50b. The first air chamber 55 is opened to the atmosphere via a first atmosphere opening 58 formed through the downstream air chamber 53. With this configuration, the first air chamber 55 (
The pressurized air sent from the second ink cartridge 10 flows into the upstream air chamber 54 and the downstream air chamber 53) via the tube T12 and the flow path 57, and the compressed air is The air is opened to the atmosphere via the first atmosphere opening 58.

  The release valve 51 is formed in the first air chamber 55 configured as described above. The release valve 51 includes a diaphragm portion 60, a support member 61, and a spring member 62. The diaphragm part 60 is comprised from flexible members, such as rubber | gum, and is formed in disk shape. When the release valve 51 is formed, the diaphragm portion 60 is accommodated in the first air chamber 55 in a state where the outer edge portion 63 is sandwiched and fixed by the first and second cases 50a and 50b. Is done. By configuring in this way, the diaphragm section 60 divides the upstream air chamber 54 and the downstream air chamber 53 in the first air chamber 55, and the central portion thereof is in the vertical direction ( It is possible to reciprocate in the upstream and downstream air chambers 54 and 53 direction. A communication hole 64 is formed at the center of the diaphragm portion 60 so as to penetrate the diaphragm portion 60. The communication hole 64 allows the upstream and downstream air chambers 54 and 53 to communicate with each other, and an annular cap portion 65 is formed at the peripheral edge (on the upstream air chamber 54 side). A disc-shaped contact plate 66 is fixedly disposed on the second case 50b so as to face the cap portion 65 directly. The contact plate 66 is made of metal or the like, and makes contact with the cap portion 65 so as to bring the communication hole 64 into a non-communication state. With this configuration, when the diaphragm portion 60 is bent downward (downstream air chamber 53 direction) and the cap portion 65 is separated from the contact plate 66, the upstream and downstream air The chambers 54 and 53 are in communication. Further, when the diaphragm portion 60 is bent upward (in the upstream air chamber 54 direction) and the cap portion 65 is in contact with the contact plate 66, the upstream air chamber 54 and the downstream air chamber 53 are It becomes a non-communication state.

  Further, a support member 61 formed in a cylindrical shape from the downstream air chamber 53 side is fitted into the communication hole 64 of the diaphragm portion 60, and is integrated with the diaphragm portion 60. As will be described later, the support member 61 receives and urges the urging force from the spring member 62 to support and urge the diaphragm portion 60 from the downstream air chamber 53 side upward (in the upstream air chamber 54 direction). An inner hole 67 is formed in the inner diameter portion. As described above, the inner hole 67 is configured to be in communication with the communication hole 64 by fitting the support member 61 into the communication hole 64 of the diaphragm portion 60 so as to be integrated. A convex portion 61 a is formed on the outer surface of the support member 61, and the convex portion 61 a comes into contact with the diaphragm portion 60 on the upper side (upstream air chamber 54 side). Thus, the support member 61 is positioned when fitted to the diaphragm portion 60.

  On the other hand, a circular groove 68 is formed in the bottom of the downstream air chamber 53 at a position facing the support member 61. The groove 68 is supported by fitting the spring member 62. The spring member 62 is disposed in the downstream air chamber 53 by being fitted in the groove 68 and fitted on the outer surface of the support member 61 and abutting against the convex portion 61a. Yes. As described above, the spring member 62 biases the diaphragm portion 60 upward (on the upstream air chamber 54 side) via the support member 61. The spring member 62 urges the diaphragm portion 60 to bring the cap portion 65 of the diaphragm portion 60 into contact with the pressure in a state where the pressure in the upstream air chamber 54 is equal to or lower than the preset reference pressure. It is set to abut against the plate 66. Further, the spring member 62 yields to the pressure of the upstream air chamber 54 transmitted through the diaphragm portion 60 in a state where the pressure in the upstream air chamber 54 is equal to or higher than the predetermined reference pressure. It is set to bend downward (downstream air chamber 53 direction).

With this configuration, in a state where the pressure in the upstream air chamber 54 of the release valve 51 is equal to or lower than the preset reference pressure, as shown in FIG. 5, the cap portion 65 of the diaphragm portion 60. Is in contact with the contact plate 66. At this time, the release valve 51 holds the pressurized air in the second ink cartridge 10 with the upstream and downstream air chambers 54 and 53 in a non-communication state. When the pressurized air flows from the second ink cartridge 10 through the tube T12 into the opening device 22 (release valve 51) from this state, the inside of the upstream air chamber 54 of the release valve 51 Pressure increases. Further, when the pressure in the upstream air chamber 54 becomes equal to or higher than the preset reference pressure, the release valve 51 causes the cap portion 65 to be separated from the contact plate 66 as shown in FIG. It has become. As a result, the release valve 51 opens the pressurized air from the first atmosphere opening port 58 with the upstream and downstream air chambers 54 and 53 in communication. At this time, the waste ink and air flowing into the check valve 14 from the gear pump GP via the tube T3 are, as described above, the first flow path 38 → the upstream valve chamber 34 → the communication hole 41 → the inner hole 44 → After flowing in order of the downstream side valve chamber 35 → second flow path 39 → tube T4, it flows into the first ink cartridge 9 as pressurized air. The pressurized air flows in the order of the first ink cartridge 9 → the tube T6 → the second ink cartridge 10 → the tube T12 → the opening device 22 (release valve 51), and then the first atmosphere opening port 58. Has been released from.

  That is, the release valve 51 is appropriately opened from the first atmosphere opening 58 via the release valve 51 when the pressurized air in the first and second ink cartridges 9 and 10 becomes a pressure higher than the reference pressure. The increase in pressure is reduced. With this configuration, the pressure in the first and second ink cartridges 9 and 10, the pressure in the tubes T4, T6 and T12 up to the opening device 22, the check valve 14 (downstream valve chamber) The pressure in 35) is suitably maintained so as to satisfy the reference pressure by appropriately releasing pressurized air from the release valve 51.

  On the other hand, a second air chamber 70 is recessed and opened in the second case of the main body case 50. The opening of the second air chamber 70 is sealed by attaching the third case 50c to the second case 50b. The second case 50b of the main body case 50 is formed with a second atmosphere opening port 71 that opens the inside of the second air chamber 70 to the atmosphere. Further, a cylindrical projecting portion 72 projects from the bottom of the second case 50b, and the second air chamber 70 is connected to the first air chamber 55 (upstream air chamber 54) at the inner diameter portion of the projecting portion 72. ) Is formed.

  With this configuration, the pressurized air sent from the second ink cartridge 10 is supplied to the second air chamber 70 from the tube T12 → the flow path 57 → the first air chamber 55 (upstream air chamber 54). Further, the pressurized air is opened to the atmosphere from the communication hole 73 through the second atmosphere opening port 71.

  The solenoid valve 52 is disposed in the second air chamber 70 configured as described above. The solenoid valve 52 includes a bobbin 74, a yoke 75, a spring member 76, a cap portion 77, a coil 78, and a housing H.

The bobbin 74 is formed in a cylindrical shape and is accommodated in the housing H. The housing H is supported on the inner surface of the second air chamber 70. The bottom of the housing H is directly opposed to the protruding portion 72 and a part thereof is open, so that the inner surface of the bobbin 74 is opened to the protruding portion 72 side through the open portion. It has become. Furthermore, a yoke 75 is slidably inserted in the inner side surface of the bobbin 74 and supported by the bobbin 74. A spring member 76 is provided between the pedestal portion 75 a of the yoke 75 and the bobbin 74, and the spring member 76 is connected to the pedestal portion 7.
The yoke 75 is always urged upward via 5a.

  A cap portion 77 formed in an annular shape is provided on an inner diameter portion of the protruding portion 72 so as to be positioned at an edge portion of the communication hole 73. The cap portion 77 is for contacting and closely contacting the yoke 75 and supporting the yoke 75 when the yoke 75 moves downward. Further, the yoke 75 is in close contact with the cap portion 77 to seal the communication hole 73 so that the first air chamber 55 (upstream air chamber 54) and the second air chamber 70 are not in communication. It has become. On the other hand, the yoke 75 is separated from the cap portion 77 to open the communication hole 73 so that the first air chamber 55 (upstream air chamber 54) and the second air chamber 70 are in communication with each other. ing.

  A coil 78 is wound around the outer surface of the bobbin 74. When a drive current is supplied to the coil 78 from a control circuit (not shown), the yoke 75 is moved downward as shown in FIG. 6 against the urging force of the spring member 76 and comes into close contact with the cap portion 77. On the contrary, when the drive current is not supplied, the yoke 75 is moved upward by being biased by the spring member 76 so as to be separated from the cap portion 77.

  That is, the solenoid valve 52 blocks the flow of the pressurized air when it is in a non-communication state, and flows the pressurized air to the atmosphere when it is in a communication state. Then, by setting the solenoid valve 52 in a communicating state, the tubes T4, T6, T12 up to the first and second ink cartridges 9, 10 and the opening device 22, the check valve 14 (downstream valve chamber 35). ) Can be opened to the atmosphere and its pressure can be made equal to atmospheric pressure.

  The solenoid valve 52 of the present embodiment is normally in a non-communication state, and the tubes T4, T6, the pressures in the first and second ink cartridges 9, 10 up to the opening device 22 are reached. The pressure in T12 and the pressure in the check valve 14 (downstream valve chamber 35) are maintained.

  In the printer 1 of the present embodiment, when the gear pump GP is driven during cleaning, the solenoid valve 52 is brought into a communication state, and the pressure in the downstream valve chamber 35 of the check valve 14 is made equal to the atmospheric pressure. It is like that.

With this configuration, when the gear pump GP is driven in the printer 1, as described above, pressurized air flows from the check valve 14 (downstream valve chamber 35) to the opening device 22. Compared with the case where the pressure is high, the pressure difference between the upstream side valve chamber 34 and the downstream side valve chamber 35 is easily set to the reference value or more. That is, since the check valve 14 is easily communicated, the time until the gear pump GP is filled with ink is short, so that suction can be completed with a short drive. For this reason, for example, when the suction is started in a state where the gear pump GP is wet and the capacity is high, the ink suction amount becomes large. However, since the suction can be completed in a short time, the ink cartridges 9, 10 ink consumption can be minimized. Further, it is not necessary to increase the suction capacity of the gear pump GP, and the load on the gear pump GP can be reduced, so that the noise is reduced.

Next, the operation of the printer 1 configured as described above will be described.
In this description, in the printer 1, the solenoid valve 52 of the opening device 22 is in an ON state, and the tubes T 4, T 6, T 12 and the first and second ink cartridges 9 and 10 and the opening device 22 are It is assumed that pressurized air flowing in the check valve 14 (downstream valve chamber 35) is held. Further, it is assumed that the cap member 12 is in contact with the recording head 8 and sealed.

  First, when performing the cleaning operation from this state, the printer 1 drives the gear pump GP after bringing the solenoid valve 52 of the opening device 22 into a communication state. When the gear pump GP is driven, waste ink and air are sucked from the cap member 12, and the waste ink and air are in order of the cap member 12 → tube T2 → gear pump GP → tube T3 → check valve 14 → tube T4. After flowing, it flows into the first ink cartridge 9. Further, this air flows as pressurized air from the first ink cartridge 9 to the second ink cartridge 10 → the tube T 16 → the opening device 22 and flows out from the second atmosphere opening port 71. When the cleaning operation is completed, the printer 1 sets the solenoid valve 52 of the opening device 22 in a non-communication state, and again drives the pump while the cap member 12 is separated from the recording head 8. Pressurized air flowing in the tubes T4, T6, T12 and the check valve 14 (downstream valve chamber 35) up to the second ink cartridges 9, 10 and the opening device 22 is held. Thereby, the ink packs B, C, M, Y, LC, and LM of the first and second ink cartridges 9 and 10 are pressurized.

  During the pressurization, the printer 1 supplies air (pressurized air) to the first and second ink cartridges 9 and 10 via the check valve 14 and appropriately supplies the pressurized air to the opening device 22. The release valve 51 is opened. Thus, the printer 1 pressurizes each ink pack B, C, M, Y, LC, and LM with the pressurized air that satisfies the reference pressure without being affected by the loss due to the flow of the pressurized air. And the fall of the pressure of the pressurized air can be reduced. Then, from the pressurized ink packs B, C, M, Y, LC, and LM, the corresponding inks are pumped to the recording head 8, so that the printer 1 can perform suitable printing. it can.

As mentioned above, according to this embodiment mentioned above, there exist the following effects.
(1) The solenoid valve 52 of the opening device 22 of the present embodiment is configured to block the flow of pressurized air when it is in a non-communication state and flow the pressurized air into the atmosphere when it is in a communication state. With this configuration, the solenoid valve 52 is brought into a communication state, whereby the tubes T4, T6, T12 up to the first and second ink cartridges 9, 10 and the opening device 22 and the check valve are provided. 14 (downstream valve chamber 35) can be opened to the atmosphere and its pressure can be made equal to atmospheric pressure. When the gear pump GP is driven, the solenoid valve 52 is brought into a communication state so that pressurized air flows from the downstream valve chamber 35 of the check valve 14 to the opening device 22 and the pressure is increased. Compared to the case, the pressure difference between the upstream valve chamber 34 and the downstream valve chamber 35 can be easily set to a reference value or more. That is, since the check valve 14 can be easily communicated, the time until the gear pump GP is filled with ink is short, so that suction can be completed with a short drive. For this reason, for example, when the suction is started in a state where the gear pump GP is wet and the capacity is high, the ink suction amount becomes large, but since the suction can be completed in a short time, the gear pump GP effective for ink suction can be used. Variations in driving time and suction amount can be reduced, and ink consumption of the ink cartridges 9 and 10 due to excessive suction can be suppressed to a minimum. Further, it is not necessary to increase the suction capacity of the gear pump GP, and the load on the gear pump GP can be reduced and the noise can be reduced. As a result, the printer 1 provided with the opening device 22 can achieve a long life and quietness of the ink cartridges 9 and 10. Further, in the present embodiment, by adopting the solenoid valve 52, the communication state and the non-communication state can be controlled only by the presence or absence of energization, and the drive motor and the position sensor for controlling the communication state and the non-communication state Therefore, the printer 1 can be configured in a small size and at low cost.
(2) In the opening device 22 of the present embodiment, when the pressure of the pressurized air in the first and second ink cartridges 9 and 10 exceeds the reference pressure, the release valve 51 causes the pressurized air to be The air opening 58 was appropriately opened. With this configuration, the pressure in the first and second ink cartridges 9 and 10 is suitably maintained at a reference pressure. As a result, even if the amount of waste ink and air flowing in from the gear pump GP suddenly increases, the rapid increase in pressure in the first and second ink cartridges 9 and 10 is reduced. Can do. Each ink pack B, C, M, Y, LC, and LM in the first and second ink cartridges 9 and 10 can be suitably pumped to the corresponding recording head 8. . As a result, the printer 1 can perform suitable printing.
(3) The check valve 14 of the present embodiment is configured to prevent the backflow of waste ink and air from the downstream valve chamber 35 toward the upstream valve chamber 34. Thereby, the backflow of waste ink and air to the gear pump GP can be prevented. As a result, it is possible to reduce the contamination of the recording head 8 as in the conventional liquid ejecting apparatus described above. Furthermore, the pressure drop of the pressurized air flowing in the first and second ink cartridges 9 and 10 can be reduced.

In addition, embodiment of invention is not limited to said each embodiment, You may change as follows.
In the above embodiment, the check valve 14 and the opening device 22 are provided. However, the present invention is not limited to this, and the check valve 14 and the opening device 22 may be integrally formed. As a result, the printer 1 can be downsized.

  In the above embodiment, the check valve 14 is provided between the gear pump GP and the first ink cartridge 9 by connecting to the tubes T3 and T4. However, the present invention is not limited to this, and the check valve 14 is connected to the tube T6 added thereto. It may also be provided between the first and second ink cartridges 9 and 10. Thus, pressurized air that satisfies the reference pressure can be supplied from the second ink cartridge 10.

  In the above embodiment, the first ink cartridge 9 and the second ink cartridge 10 are provided. However, the present invention is not limited to this, and the first ink cartridge 9 and the second ink cartridge 10 may be integrally formed. At this time, it is desirable to appropriately change the configuration of the printer 1.

  In the above-described embodiment, the first ink cartridge 9 and the second ink cartridge 10 are provided. However, the present invention is not limited to this. Ink cartridges B, C, M, Y, LC, and LM are provided as independent ink cartridges. It may be formed. With this configuration, each ink cartridge can be managed individually, so that the reliability of the ink stored in each ink pack B, C, M, Y, LC, and LM can be improved. In addition, by preparing a plurality of ink cartridges, more ink can be supplied to the recording head 8. At this time, it is desirable to appropriately change the configuration of the printer 1.

  In the above embodiment, the ink absorber 17 is provided in the first ink cartridge 9. However, the present invention is not limited to this, and the ink absorber 17 may be provided in the second ink cartridge 10 in addition to this. As a result, even when waste ink flows into the second ink cartridge 10, it can be quickly absorbed.

In the first embodiment, the ink pack B is accommodated in the first ink cartridge 9 and the ink packs C, M, Y, LC, and LM of the second ink cartridge 10 are accommodated. May be accommodated. Therefore, for example, the ink packs B and C are accommodated in the first ink cartridge 9, and the ink packs M, Y, and LC are accommodated in the second ink cartridge 10.
, LM may be accommodated. Further, the first or second ink cartridges 9 and 10 may further contain ink packs of the same color or other colors. At this time, it is desirable to appropriately change the configuration of the printer 1 so that each ink can be supplied to the recording head 8.

  In the above-described embodiment, the liquid ejecting apparatus is embodied in the printer 1. However, the present invention is not limited to this, and the liquid ejecting apparatus may be embodied in a liquid ejecting apparatus that ejects another liquid. For example, as a liquid ejecting apparatus for ejecting liquids such as electrode materials and color materials used in the manufacture of liquid crystal displays, EL displays, and surface-emitting displays, as a liquid ejecting apparatus for ejecting bioorganic materials used in biochip manufacturing, and as precision pipettes The sample injection device may be used. Accordingly, the configuration of the first and second ink cartridges 9 and 10 may be changed as appropriate.

FIG. 2 is a perspective view for explaining the outline of the printer according to the embodiment. FIG. 3 is a block diagram for explaining an ink supply system to a recording head according to the embodiment. Sectional drawing for demonstrating the structure of the check valve of the embodiment. (A) Cross-sectional view for explaining the structure of the check valve of the embodiment, (b) Cross-sectional view for explaining the structure of the check valve of the embodiment, (c) The structure of the check valve of the embodiment. Sectional drawing for demonstrating. Sectional drawing for demonstrating the structure of the opening | release apparatus of the embodiment. Sectional drawing for demonstrating the structure of the opening | release apparatus of the embodiment. Sectional drawing for demonstrating the structure of the opening | release apparatus of the embodiment. The block diagram for demonstrating the outline of the conventional liquid ejecting apparatus.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Printer as liquid ejecting apparatus, 8 ... Recording head as liquid ejecting head, 9 ... First ink cartridge constituting waste liquid tank, 12 ... Cap member, 22 ... Opening device as opening means, 52 ... Solenoid valve GP ... Gear pump as suction means.

Claims (5)

A liquid container for storing liquid;
A liquid ejecting head that ejects the liquid supplied from the liquid container;
A cap member for receiving the waste liquid discharged from the liquid jet head;
A waste liquid tank for storing the waste liquid;
A liquid ejecting apparatus comprising suction means for sucking the waste liquid from the cap member and introducing the waste liquid into the waste liquid tank;
A liquid ejecting apparatus comprising an opening means for opening the waste liquid tank to the atmosphere. The liquid ejecting apparatus according to claim 1,
The waste liquid tank stores the liquid waste and stores the liquid container.
In addition to sucking the waste liquid from the cap member and introducing the waste liquid into the waste liquid tank, the suction means sucks air from the cap member to pressurize the liquid container, so that the liquid is liquid. A liquid ejecting apparatus that is supplied to an ejecting head. The liquid ejecting apparatus according to claim 1 or 2,
The liquid ejecting apparatus according to claim 1, wherein the opening means is a solenoid valve that opens the waste liquid tank when in a communicating state. A liquid container for storing liquid;
A liquid ejecting head that ejects the liquid supplied from the liquid container;
A cap member for receiving the waste liquid discharged from the liquid jet head;
A liquid ejection apparatus driving method comprising: a waste liquid tank that stores the waste liquid; and a suction unit that sucks the waste liquid from the cap member and introduces the waste liquid into the waste liquid tank.
The method for driving a liquid ejecting apparatus according to claim 1, wherein when the waste liquid is sucked by the suction means, the waste liquid tank is opened to the atmosphere. The method for driving a liquid ejecting apparatus according to claim 4,
The waste liquid tank stores the liquid waste and stores the liquid container.
In addition to sucking the waste liquid from the cap member and introducing the waste liquid into the waste liquid tank, the suction means sucks air from the cap member to pressurize the liquid container, so that the liquid is liquid. A method for driving a liquid ejecting apparatus, comprising: supplying the ejecting head to a liquid ejecting head.

Images