Ink jet recording device

Description: TECHNICAL FIELD [Detailed description of the invention]

[Industrial application field] The present invention relates to an inkjet recording device, and more particularly to an inkjet recording device provided with a mechanism for preventing dry clogging of the discharge port of a head in a non-recording area such as a home position. [Conventional technology] Recording devices such as printers and facsimiles are classified into thermal type, wire dot type, inkjet type and the like depending on the recording method. Of these, the inkjet type supplies ink to a recording head having at least one fine liquid passage, and drives an energy generator provided in the liquid passage based on print data to obtain ink in the liquid passage. It is configured to apply pressure to eject ink from the ejection port to form flying droplets, and then attach the ink droplets to a recording sheet such as recording paper or a thin plastic plate to form a dot pattern. There is. By the way, in this type of inkjet recording apparatus, the ejection port may be clogged due to ink thickening due to evaporation of the ink solvent, adhesion of dust, mixing of air bubbles, and the like. In order to prevent this and enable stable discharge, a discharge recovery means is provided. As this ejection recovery means, generally, the ejection port of the head is capped with a rubber cap or the like, and a negative pressure is generated by the suction means in the space formed in the cap to suck the ink, or the ink supply side pressurizes and discharges the ink. A configuration is used in which ink is discharged from the outlet to perform a recovery operation. The capping mechanism is installed facing the home position, and the cap is moved forward and backward toward the discharge surface (head surface) of the head so that it can be pressure-welded or retracted. As a means for moving the cap, a motor, an electromagnetic solenoid, or the like is used as a drive source. [Problems to be solved by the invention] However, in such a conventional inkjet recording device, the cap attachment state is uniquely determined at the time of assembly. Therefore, when the head surface is tilted even a little, the sealed state between the cap and the head surface cannot be maintained accurately, causing poor capping. In order to avoid this state and maintain the sealed state between the cap and the head surface at the time of capping, it is necessary to strongly press the cap against the head surface. Therefore, a high torque type has to be used for the drive motor, and the power consumption is large. Further, since the cap using rubber is compressed, the volume of the cap closed space is reduced and the pressure is applied, which causes the meniscus in the nozzle to recede and causes a discharge failure. The present invention has been made in view of the above-mentioned technical problems, and an object of the present invention is to make the contact pressure between the cap and the discharge surface uniform and adhere even if the discharge surface of the recording head is inclined. By improving the performance, it is possible to reduce the required pressing force of the cap when covering the discharge surface of the recording head with the cap, thereby reducing the power consumption required for driving the cap and improving the durability of the cap. It is to provide an inkjet recording apparatus capable of achieving the above. [Means to solve problems] In order to achieve the above object, the inkjet recording apparatus of the present invention has a carriage for moving a recording head that ejects ink from an ejection port according to recording information and records in a recording area in a predetermined direction, and the recording area. When the carriage is located in the non-recording area deviated from the recording head, the discharge surface of the recording head provided with the discharge port is covered, and a cap for recovering the discharge of the recording head and the cap are attached. A movable member for mounting the mounting member so that the cap can swing up and down, left and right, and a movable member for pressing the movable member in a direction in which the cap covers the discharge surface. It has an elastic force generating means for generating an elastic force and a cam for moving the movable member in a direction opposite to the covering direction against the elastic force generated by the elastic force generating means. The cam is separated from the movable member when the cap covers the discharge surface. [Activity] According to the above configuration, since the cap is mounted so as to be swingable up and down and left and right, even if the discharge surface of the head is inclined, the cap can be uniformly contacted over the entire circumference, so that the adhesion of the cap is good. Can be improved and the required pressing force of the cap can be reduced. Further, the cam for moving the cap in the separation direction against the elastic force generating means for pressing the cap against the discharge surface is separated from the movable member when the cap covers the discharge surface. The cap covers the discharge surface only by elastic force, and the uniform contact and adhesion of the cap can be made more reliable. By these actions, it is possible to reduce the power consumption required for driving the cap and improve the durability of the cap, and even if the head mounting deviates from the specification value or is tilted due to aging, good adhesion is always achieved. Capping that keeps the sex can be done. [Example] Hereinafter, the present invention will be specifically described with reference to FIGS. 1 to 11. FIG. 1 is a schematic perspective view showing an embodiment of an inkjet recording apparatus according to the present invention. In FIG. 1, 1 is a base on which the following members are mounted, and side plates 1a and 1b and an intermediate side plate 1c are erected. Reference numeral 2 denotes a reed screw rotatably supported between the side plates 1a and 1b. The lead screw 2 has a feed screw portion 2a formed in a threaded strip at a predetermined pitch and a groove 2b at one end. 3 is a transmission gear provided at one end of the lead screw 2, and 4 is slidably engaged with the transmission gear 3 in the axial direction so that the driving force is transmitted in the rotational direction so as to approach the transmission gear 3. This is a clutch gear that is externally fitted to the lead screw 2. Reference numeral 5 denotes a coil spring that is mounted between the transmission gear 3 and the clutch gear 4 and constantly urges the clutch gear 4 toward the recording region. In order to regulate the position of the clutch gear 4 urged by the coil spring 5, the C ring 6 is engaged with the groove 3b formed on the outer periphery of the end portion of the transmission gear 3 as shown in FIG. There is. Reference numeral 7 is a carriage, the details of which are as shown in FIG. In the figure, 7a and 7b are bearing parts that fit into the lead screw 2, 7c is a pressing part that comes into contact with the clutch gear 4 when the carriage reaches the home position, and 7d is the light of the interrupter 28 for detecting the home position of the carriage. Shielding plate for shielding, 7e is a protruding guide part provided on both sides of the front part, 7f is a head lock lever integrally formed with the carriage 7 using an elastic plastic material such as polyacetal, 7g is a head The hook portion 8 formed on the front portion of the lock lever 7f is a drive pin that is diagonally attached at a predetermined position of the carriage 7 and along the lead angle of the lead screw 2 as shown in FIG. Reference numeral 9 denotes a "U" -shaped carriage spring provided at the bottom of the carriage 7, as shown in FIG. Reference numeral 9a is a pressure contact portion formed at one end of the carriage spring 9, and a guide roller 10 is rotatably provided at the tip portion thereof, and the rail portion 101 of the base 1 is pressed by the guide roller 10. Reference numeral 9b is a pad holding portion, and as shown in FIG. 6, a pad 11 pressed against the lead screw 2 is attached to the tip. 9c is a flip-up part to facilitate the removal of the head. In No. 12, the head portion 12a provided with the electric heat exchanger that generates thermal energy as energy used for ejecting ink and the ink tank 12b that stores the ink supplied to the head portion 12a are integrally attached to the carriage. It is a disposable head that can be attached and detached, and is installed as shown in Fig. 5. 12c is a mounting pin inserted into the mounting portion of the carriage 7, and 12d is a hook portion formed at the rear end of the head 12 to which the hook portion 7g is engaged when the head 12 is mounted. Reference numeral 13 denotes a flexible contact provided on the upper surface of the carriage 7 and capable of contacting the electrode of the head 12, and 14 is a paper feed roller arranged in parallel with the lead screw 2 and carrying the recording sheet while winding it. Reference numeral 15 denotes a paper feed motor that rotationally drives the paper feed roller 14, 16 is a printing paper as a recording medium, and 17 is a paper pan that serves as a guide for the printing paper 16 that is fed to the paper feed roller 14. Reference numeral 18 denotes a paper holding plate that prevents the printing paper 16 from bending toward the head 12 at the printing position, 18a is a guide surface on which the guide portion 7e of the carriage 7 slides, and 19 is a motor that is a drive source of the carriage 7. 19a is a stay for fixing the motor 19 to the side plate 1a, 19b is the rotating shaft of the motor 19, 20 is a pinion attached to the shaft end of the rotating shaft 19b, 22 is a pinion that meshes with the pinion 20 and the transmission gear 3. It is an idle gear that transmits the rotation of 20 to the transmission gear 3, and one end of the gear shaft 21 is pivotally supported by the side plate 1a. Reference numeral 23 denotes a cap gear that is coaxially supported by the idle gear 22 and rotates the cap 243. The cap gear 23 is integrally processed with a cam 23a for swinging the cap lever (movable member) 241 (FIG. 7). Reference numeral 24 denotes a cap unit rotatably attached to the lever shaft 25, which includes a contact portion 24a that abuts on the cam 23a and a spring portion 24b that applies a rotational force to the cap unit 24. 242 is a cap holder (mounting member, Fig. 8) mounted on the front surface of the cap unit 24, 27 is an ink absorber for preliminary ejection mounted on the intermediate side plate 1c after being subjected to a porous hydrophilic treatment, 28. Is an interrupter for home position detection provided on the bottom surface of the base 1 near the transmission gear 3. Reference numeral 29 denotes a blade, which is made of an elastic material such as rubber and is attached to the intermediate side plate 1c of the base 1. Since the recording head and the cap are positioned using the lead screw in this way, the position accuracy at the time of capping is improved. FIG. 7 is a perspective view showing the details of the cap unit 24 including the cap lever 241 and the cap 243, and FIG. 8 is an exploded perspective view showing the details of the cap 243. 241 is a cap lever as a movable member and is rotatably attached to a lever shaft 25 attached to the intermediate side plate 1c of the base 1 to give a rotational force to the abutting portion 241a abutting the cam 23a and the cap lever 241. Spring (elastic force generating means) 241b is integrally formed. Further, the cap lever 241 is integrally formed with a hook portion 241c for attaching the cap holder 242, which will be described later, a guide portion 241d, and a hemispherical R-shaped protrusion 241e that abuts on the cap holder 242. In this embodiment, the cap lever 241 is processed by using an elastic plastic material such as polyacetal, but the cap lever 241 is not limited to this as long as it is a material exhibiting the same characteristics. Reference numeral 242 shown in FIG. 8 is a metal cap holder, and a mounting portion 242a for mounting on the cap lever 241 is integrally formed. The mounting portion 242a is loosely fitted in the space formed by the hook portion 241c and the guide portion 241d so that the entire cap holder 242 can swing in all directions such as up and down, left and right, and diagonally. As a result, it is possible to improve the adhesion by uniform contact between the head and the cap during capping. Reference numeral 243 is a cap, and a hook portion 243a (FIG. 9) for fitting to the cap holder 242 is integrally formed on the rear surface thereof. Further, a rib 243b (the height thereof is set so that the cap member does not come into contact with the discharge port of the head 12) is formed on the front surface of the cap 243 to improve the adhesion with the head 12. The rib 243b is made of a highly flexible member such as a rubber material. By lowering the height so that the cap member does not come into contact with the discharge port of the head 12, the surface area inside the cap during capping is reduced, and the ink is prevented from drying and solidifying due to the gas permeability of the rib 243b. Can be done. FIG. 9 is a cross-sectional view showing a state in which the cap holder 242 with the cap 243 attached is attached to the cap lever 241. Next, the operation of the embodiment with the above configuration will be described with reference to FIGS. 10 (a) to 10 (h). First, when the motor 19 shown in FIG. 1 rotates, the driving force is sequentially transmitted via the pinion 20 and the idle gear 22, and the transmission gear 3 rotates. The rotation of the transmission gear 3 causes the reed screw 2 to rotate. When the lead screw 2 rotates in the direction of arrow A in the figure, the carriage 7 moves in the direction of arrow a. Conversely, when the lead screw 2 rotates in the direction of arrow B, the carriage 7 moves in the direction of arrow b. The reed screw 2 alternately rotates in the direction of arrow A or B according to the recorded information, reciprocates the carriage 7 along the reed screw 2, and in the process, ejects ink droplets from the ink ejection port of the head 12. Next, the recovery operation when waiting for print data and turning off the power will be described. First, as shown in FIG. 10A, the reed screw 2 is rotated in the direction of arrow B in FIG. 1 to move the carriage 7 in the direction of arrow b, and when the recording area is removed, the blade 29 is connected to the head 12 of the head 12. The discharge surfaces come into contact with each other and pass through, and the discharge surfaces are cleaned. When the carriage 7 moves further from this state, the pressing portion 7c comes into contact with the clutch gear 4. The pressing portion 7c of the carriage 7 pushes the clutch gear 4 against the urging force of the coil spring 5, moves the clutch gear 4 from the state of FIG. 10 (a) as shown in the state of FIG. 10 (b), and caps the clutch gear 4. Engage with gear 23. At this time, since the cam 23a remains stationary, the head portion 12a is separated from the cap 243 as shown in FIG. 10 (e). In the state shown in FIG. 10B, the rotation of the idle gear 22 is transmitted to the cap gear 23 via the transmission gear 3 and the clutch gear 4, the cam 23a coaxial with the cap gear 23 rotates, and the cap lever 241 Is swung in the direction of arrow c shown in Fig. 10 (f). When the carriage 7 moves to a state where the clutch gear 4 completely meshes with the cam 23a as shown in FIG. 10 (c), the drive pin 8 falls into the groove 2b of the lead screw 2 and the movement of the carriage 7 stops. However, the cam 23a continues to rotate, and after pressing the cap lever 241 once immediately after lowering from the horizontal position, the cap lever 241 moves clockwise along the surface of the cam 23a as the rotation of the cam 23a progresses. Rotate. As the cap lever 241 rotates, the cap 243 approaches the head portion 12a, and finally the two are pressed against each other as shown in FIG. 10 (h). At this time, the positional relationship of each gear is in the state of FIG. 10 (d), which is the same as the state of FIG. 10 (c). The pressing force of the cap 243 can be arbitrarily set by selecting the elastic force of the spring portion 241b of the cap lever 241. In this way, when the cap 243 covers the discharge surface of the head 12, the cam 23a separates from the movable member (cap lever) 241 and the cover of the discharge surface by the cap 243 generates an elastic force generating means (spring) 241b. By configuring it so that it is performed only by the elastic force to be applied, the cap 243 can be smoothly and surely attached to and detached from the discharge surface, and the cover of the cap 243 to the discharge surface can be stably covered with a constant force. It is possible to ensure that the entire cap is in uniform contact with the discharge surface (uniform contact). Next, when printing is performed by opening the cap 243, the operation opposite to the capping operation described above may be performed. First, when the motor 19 is rotated to rotate the lead screw 2 in the direction of arrow A, the cap gear 23 and the clutch gear 4 are engaged with each other, so that the cap gear 23 rotates. The cam 23a rotates in conjunction with this rotation, the cap lever 241 is rotated, the cap 243 and the head portion 12a of the head 12 are separated from each other, and the cap 243 is opened. When the lead screw 2 further rotates from this state, the carriage 7 is always urged in the direction of arrow A by the coil spring 5, so that the drive pin 8 is fitted at the position where it engages with the lead groove 2a, and the carriage 7 is engaged. Move in the direction of arrow a in Fig. 1. As the carriage 7 moves, the clutch gear 4 moves together, the clutch gear 4 and the cap gear 23 are disengaged, and the rotation of the cap gear 23 stops. FIG. 11 is a cross-sectional view showing details of other embodiments of the cap unit. The difference from FIG. 7 of this cap lever 241 is that the mounting portion 242a of the cap holder 242 is formed in a spherical shape, the hook portion 241c of the cap lever 241 is formed in an R shape, and the cap holder 242 is specified on the left, right, top and bottom. It is a play of. Even with such a configuration, the same effect as the configuration of the cap lever 241 of FIG. 7 can be obtained. [Effect of the invention] As is clear from the above description, according to the inkjet recording apparatus of the present invention, a carriage for moving the recording head for recording in the recording area in a predetermined direction by ejecting ink from the outlet according to the recording information. When the carriage is located in a non-recording area outside the recording area, a cap for covering the discharge surface of the recording head provided with the discharge port and recovering the discharge of the recording head, and the cap. A mounting member for mounting the cap, a movable member for mounting the mounting member so that the cap can swing up and down, left and right, and the movable member pressed in a direction in which the cap covers the discharge surface. The elastic force generating means for generating the elastic force and the cam for moving the movable member in the direction opposite to the covering direction against the elastic force generated by the elastic force generating means. Since the cam is configured to be separated from the movable member when the cap covers the discharge surface, the recording head can be discharged by mounting the cap so as to be swingable up and down and left and right. Even if the surface is tilted, the entire cap can be brought into uniform contact to improve the adhesion of the cap and reduce the required pressing force of the cap, and further, against the elastic force generating means. Since the cam for moving the cap in the separation direction is separated from the movable member when the cap covers the discharge surface, the cap can be pressed against the discharge surface only by an elastic force. This makes it possible to ensure uniform contact and adhesion of the cap, thereby reducing the power consumption required for driving the cap and improving the durability of the cap, and the head mounting is specified. Provided is an inkjet recording apparatus capable of always maintaining good adhesion when the cap covers the discharge surface even if the value deviates or tilts due to aging.

[Simple explanation of drawings]

FIG. 1 is a schematic perspective view showing an embodiment of an inkjet recording apparatus according to the present invention, FIG. 2 is an exploded perspective view showing details of three transmission gears in FIG. 1, and FIG. 3 is in FIG. FIG. 4 is an exploded perspective view showing the details of the carriage 7 of the above, FIG. 4 is a schematic side view showing the engagement between the drive pin 8 of the carriage 7 and the lead groove 2a of the lead screw 2, and FIG. FIG. 6 is a schematic side view showing the mounted state of the pad 11, FIG. 6 is a schematic side view showing the mounted state of the pad 11, and FIG. 7 is a perspective view showing details of the cap unit 24 including the cap lever 241 and the cap 243. Is an exploded perspective view showing the details of the cap 243, FIG. 9 is a cross-sectional view showing a state in which the cap holder 242 is attached to the cap lever 241, and FIGS. FIG. 11 is a schematic side view of the gear portion for explaining the above, and FIG. 11 is a cross-sectional view showing details of another embodiment of the cap unit 24. 1 ...... base, 2 ...... lead screw, 2a ...... lead groove, 3 ...... transmission gear, 4 ...... clutch gear, 5 ...... Coil spring, 7 ...... Carriage, 8 ...... Drive pin, 12 ...... Recording head (head), 19 ...... Motor, 22 ...... Idle gear, 23 ...... Cap gear, 23a ...... Cam, 24 ...... Cap unit, 241 ...... Movable member (cap lever) ), 241b ...... Elastic force generating means (spring), 241c ...... Hook part, 241d ...... Guide part, 242 ...... Mounting member (cap holder) , 242a, 242b ...... Mounting part, 243 ...... Cap, 243b ...... Rib.