JP2705961B2 - Ink jet recording device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an ink jet recording apparatus.

[Related Art] This type of apparatus has a configuration specific to a method of performing recording by discharging ink in addition to a configuration relating to direct recording.

In other words, if the ejection is not performed for a long time at a certain ejection port or the apparatus itself is not used for a long period of time, the ink in the ejection port or the ink chamber communicating with the ejection port increases due to moisture evaporation. Viscous non-ejection may occur, and ink droplets,
In some cases, water droplets or dust adheres, and the ink droplets ejected by these adherents are pulled, and the ejection direction may be deflected. For this reason, the inkjet recording apparatus has various configurations as a so-called ejection recovery system in order to prevent non-ejection and deflection of the ejection direction.

These ejection recovery systems include a structure for preventing non-ejection, a preliminary ejection for ejecting ink to a predetermined ink receiving medium to eliminate thickened ink, etc., and a suction for absorbing ink from an ejection port or an ink liquid chamber. In addition, there is capping which performs ink suction and further seals the ejection port surface to prevent evaporation of ink moisture from the ejection port.

Further, as a configuration for preventing deflection of the discharge direction, there is a configuration in which the discharge port surface is pinged to remove dust, ink droplets, and the like attached near the discharge port.

On the other hand, in recent ink jet recording apparatuses, especially recording heads, the production thereof is performed by a semiconductor film forming process or a micromachining technique, and a smaller and less expensive recording head is being realized. For this reason, for example, a disposable recording head in which an ink tank is integrated has been proposed.

As a result, there has been a demand for an ink jet recording apparatus which is small and inexpensive, and which can be used more easily by the user.

[Problems to be Solved by the Invention] By the way, there are various problems to be solved in order to realize the above-described ink jet recording device, particularly a device corresponding to a small and inexpensive, and further, a disposable type recording head.

These problems mainly exist in the above-described configuration for ejection recovery, and the space for arranging devices for preliminary ejection, ink suction, and capping hinders miniaturization of the device. In addition, the size reduction of the apparatus is hindered by a space such as a waste ink tank for storing waste ink by preliminary ejection or suction, a suction pump and a tube for guiding waste ink to the waste ink tank.

Among the above-described recovery system configurations, a configuration that particularly performs ink suction has conventionally been, for example, as shown in FIG. 26A, a cap 100 that caps an ink discharge port surface, and a pump 101 that suctions ink. And a connecting tube 102 for connecting the cap 100 and the pump 101.
Further, as shown in FIG. 26 (B), the pump 101 performs suction and discharge by a configuration in which a one-way valve 104 is provided on the end face of the shaft of the piston 103. The one-way valve is made of a material such as rubber around the one-way valve.

However, in the above conventional recovery system, the cap 100
Requires a connection tube 102 from the pump 101 to the pump 101 and a drain tube 106 from the pump 101 to the waste ink tank 105, which complicates the configuration of these devices and also requires a space for arranging the tubes. There was a problem of becoming.

In addition, the presence of the tube increases the evaporation of the ink moisture from the tube, and the ink in the tube and in the vicinity of the discharge port thickens and may eventually adhere.

Further, since the one-way valve is provided on the piston shaft, the area of the end portion of the piston shaft, which is the mounting portion, is required to some extent. For this reason, there is also a problem that the diameter of the piston becomes large, and eventually the pump itself becomes large. In addition, in this pump, the solid rubber generally used to form the body of the piston has a large load against deformation, so that the operating force of the piston is not uniform and a stable suction operation cannot be performed. was there. In addition, since the solid rubber piston has poor durability and does not have a tolerance for dust and the like that can enter by suction, the suction effect may be significantly reduced.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems relating to the configuration of an ink suction pump in recovery of ejection, and a main object of the present invention is to solve the above problems with respect to a piston which is a component of a pump for suction. To provide an improved ink jet recording apparatus.

Means for Solving the Problems According to the present invention, there is provided an ink jet apparatus including a suction pump for sucking ink from a discharge port of a recording head for performing recording by discharging ink from a discharge port to improve an ink discharge state. In the recording apparatus, the suction pump has a cylinder and a piston reciprocating in the cylinder, and has a layer of an elastic porous body as an inner layer viewed from a sliding portion of the piston with the cylinder.

According to another aspect of the present invention, there is provided an ink jet recording apparatus including a suction pump for sucking ink from a discharge port of a recording head for performing recording by discharging ink from a discharge port to improve an ink discharge state. The pump has a cylinder and a piston that reciprocates in the cylinder, and has a layer of an elastic porous body as an inner layer viewed from a sliding portion of the piston with the cylinder, and the piston has a solid layer on the ink suction side. And performing negative pressure formation and ink recovery path formation.

[Operation] According to the above configuration, the elastic porous body is used for the piston body of the pump for discharging the waste ink to the waste ink tank or the like in the suction pump along with the suction operation for the discharge recovery. The operating force can be made uniform.

In another embodiment of the present invention, the piston shaft of the suction pump also serves as a one-way valve.

Examples Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 is an overall perspective view showing a liquid jet recording apparatus (inkjet printer) according to one embodiment of the present invention, and FIGS. 2 (A) to 2 (C) show discharge port formation of a recording head provided in the printer. FIG. 3 is a partial perspective view for explaining each part of the means for improving the surface, FIG. 3 is an exploded perspective view of the recovery system, and FIG. 4 is a cross-sectional view of the pump unit.

First, in FIG. 1, reference numeral 1 denotes a chassis, and a left side plate 1a and a right side plate 1b which also serve as guides for a recording medium such as paper are erected on the back side. A front plate 1c is provided upright on the right end, and a carrier guide plate 1d is provided upright on the near side.
Reference numeral 1e denotes an elongated hole for guiding the carrier, into which a carrier guide roller described later fits and slides. Chassis 1
Has a motor mounting hole for rotatably supporting a carrier motor described later, but is not shown.

1h is a lead arm that supports a lead screw described later in the axial and radial directions, and a bearing (not shown).
It is pivoted on.

Reference numeral 2 denotes a lead screw, in which lead grooves 2a are formed at a predetermined pitch relative to a recording range. On the carrier home position side of the lead screw 2, a cap groove 3b for setting a cap position and a pump groove 3c for setting a recovery position are formed around a section perpendicular to the axis. The groove 3c is smoothly continuous with the connecting groove 3d. In addition, lead groove
Similarly, 2a and the cap groove 3b are smoothly connected by the introduction groove 3e.

A shaft 2g is provided at the right end of the lead screw 2 and a shaft is also provided at the left end side. The shafts are fitted into bearings provided on the front plate 1c and the lead arm 1b, respectively, and are rotatably supported by them. You. Reference numeral 3 denotes a lead pulley including the grooves 3b to 3e and provided on a shaft of the lead screw 2, and a pulley 3a is provided at an end thereof. Then, a driving force is transmitted from the motor 11 to the pulley 3a via the timing belt 13. In addition, lead screw 2
2g is pressed in the thrust direction by a leaf spring or the like (not shown).

Reference numeral 4 denotes a clutch gear, which is slidably supported in the axial direction by the lead pulley 3 and engages with a rotation stopper (not shown) in the rotational direction to transmit the rotational power of the lead screw 2. Reference numeral 5 denotes a clutch spring, which is a compression spring that urges the clutch gear 4 in the lead groove direction. Although a regulating member for preventing the clutch gear 4 from moving only within a predetermined range is formed between the clutch gear 4 and the lead pulley 3, it is not shown.

Reference numeral 6 denotes a carrier, which is slidably attached to the lead screw 2. Reference numeral 6a denotes a pressing portion for pressing the end face of the clutch gear 4, which is integrally formed on the left side of the carrier. Reference numeral 6b denotes a detection piece for detecting the home position of the carrier 6. Reference numeral 7 denotes a lead pin which is engaged with the lead groove 2a of the lead screw 2 and is guided by a guide hole (not shown) of the carrier 6. Reference numeral 8 denotes a lead pin spring, one end of which is attached to the carrier 6 and which presses the lead pin 7 at the other end.

Reference numeral 9 denotes a recording head mounted on the carrier 6. In this example, a head element 9a for performing ink ejection and an ink tank 9b serving as an ink supply source are integrated to form a cartridge that can be attached to and detached from the carrier 6. It has a disposable type that can be replaced when ink is consumed. Note that, as a discharge energy generating element disposed on the head element 9a to apply discharge energy to ink, an electrothermal converter or an electromechanical converter is used.
The former is preferably used because ink ejection ports and the like can be mounted at high density and the manufacturing process is simplified.

Reference numeral 10 denotes a carrier roller, which is rotatably attached to the rear end face side of the carrier 6 and rotatably engages with the above-described elongated hole 1e of the chassis 1.

Reference numeral 11 denotes a carrier motor composed of, for example, a pulse motor. Rotating pins 11a are provided below the front and rear surfaces in an aligned state. The rotating pins 11a (the rear surface side is not shown). ) Is rotatably mounted in a motor mounting hole provided in the chassis 1. The carrier motor 11 is mounted so as to be rotatable around a rotation pin 11a. A spring receiver 11b is formed integrally with the carrier motor 11 and stands upright in parallel with the motor shaft to receive a motor spring 14, which will be described later. A columnar projection is formed on the spring receiving portion, and an end of the coiled motor spring 14 is fixed.

Reference numeral 12 denotes a motor pulley, which is fixed to the motor shaft of the carrier motor 11. Reference numeral 13 denotes a timing belt, and a pulley 3a provided on the shaft of the motor pulley 12 and the lead screw 2.
It is stretched between. The motor spring 14 is a compression spring in the configuration of the present embodiment, and is mounted between one end of the lead arm 1h and a spring receiver 11b of the carrier motor 11, whereby the carrier motor 11 rotates in the direction A in the figure. If the timing belt 13 is biased to move, tension is applied to the timing belt 13.

Reference numeral 15 denotes a set shaft, which is erected on the left side plate 1a, and is provided with means for improving the discharge port forming surface, and a cap and a mechanism relating to discharge recovery.

Means for improving the ejection port forming surface will be described with reference to FIGS. 1 and 2A to 2C.

Reference numeral 16 denotes a blade lever (see FIG. 2A), and a boss 16a is rotatably attached to the set shaft 15. 16b
Denotes an arm, and 16c denotes a hook. Reference numeral 17 denotes a blade for wiping the discharge port forming surface, which can be formed of an elastic member such as silicon rubber or chloroprene (CR) rubber. Reference numeral 18 denotes a blade shaft, which clamps the blade 17 at the center in parallel with the rotation axis and is rotatably attached to the blade lever 16. Reference numeral 18a denotes a rotating piece, which is formed integrally with the blade shaft 18. Reference numeral 19 denotes an ink carrier, which is formed of a hydrophilic porous material (a plastic sintered body, urethane foam, or the like), and is fixed to the blade lever 16. Note that the blade 17 and the ink carrier 19 are arranged at positions overlapping with caps described later.

Reference numeral 20 denotes a set lever, which is rotatably attached to the set shaft 15. 20a and 20b are stop teeth provided on the set lever 20, 20c is a start tooth, 20d is a rotary tooth, and the thickness of the start tooth 20c is about half the other. 20e
Is an arm portion, a part of which is cut out in the thickness direction to form a set surface 20f and a reset surface 20g, and a rotating piece 18a of a blade shaft 18 attached to the blade lever 16 is fitted. Have been combined to drive this.

Reference numeral 21 denotes a timing gear, which is rotatably attached to the chassis 1.

As shown in FIG. 2 (B), the timing gear 21 has a stop cam 21a formed on a part of the outer periphery thereof for engaging with the stop teeth 20a, 20b of the set lever 20 described above. Also, drive teeth 21b ₁ , 21b ₂ ,... Partially omitted are formed, and cap cams 21c to 21e for swinging a cap lever described later are formed at predetermined positions. in addition,
A piston set cam 21f for pressing a piston of a pump described later is formed as a face cam, and a piston reset cam 21g is integrally formed at a predetermined interval corresponding to the piston set cam 21f.

Reference numeral 22 denotes an ink absorber spring, which is fixed at a predetermined position on the chassis 1 and, as shown in FIG. 2 (C), has an absorber holder 22a and a spring 22b for rotating a pump described later. have. Reference numeral 23 denotes an ink absorber, which is formed of a hydrophilic porous material in the same manner as the ink carrier 19 described above. The ink absorber 23 has a wiping portion 23a with which the above-mentioned blade 17 contacts, and further has an absorbing surface 23b with which the above-mentioned ink carrier 19 makes contact and transfers ink. . Note that the absorber holding portion of the ink absorber spring 22 is urged upward with a slight elastic force, and is locked at a predetermined position by a stopper (not shown). Therefore, the ink carrier 19 described above is used.
When the ink comes into contact, the ink absorber 23 is displaced downward by bending the ink absorber spring 22, so that the contact state is ensured.

Next, the recovery system unit will be described mainly with reference to FIG. 3 and FIG.

3 and 4, reference numeral 24 denotes a cylinder;
It has a cylindrical cylinder portion 24a and a guide portion 24b for guiding a piston shaft, which will be described later. The guide portion 24b has an ink flow path 24c formed by cutting a part in the axial direction. Reference numeral 24d denotes a cap lever receiver, which is formed so that a later-described lever seal is fitted therein. Also,
Reference numeral 24e denotes an ink flow path, which is opened at a predetermined position in the cylinder portion 24a. 24f is a rotating lever,
And the turning power is given by the spring portion 22b of the ink absorber spring 22 described above. Reference numeral 24g denotes a waste ink tube, which is formed integrally with the cylinder 24 and whose end is cut at an acute angle to facilitate insertion into a waste ink absorber described later. 24b is an ink flow path formed in the waste ink tube 24g.

Reference numeral 25 denotes a cylinder cap, which is press-fitted into the end of the cylinder 24. Reference numeral 25a denotes a lever guide, which is arranged at a position facing the cap lever receiver 24d of the cylinder 24 described above.

26 is a piston seal fitted into the cylinder 24,
The inner diameter is made slightly smaller so that a predetermined pressure contact force with a piston shaft described later is obtained. Further, a lubricating coating may be applied to the surface to reduce the sliding force of the piston shaft.

Reference numeral 27 denotes a piston shaft, which includes an operation shaft 27a, a piston presser 27b,
A piston receiver 27c, a connecting shaft 27d, and a guide shaft 27e are formed, and a groove 27f serving as an ink flow path is formed on the connecting shaft 27d.
And along the guide shaft 27e. Reference numeral 27g denotes a detent, which is formed as a groove on the operation shaft 27a. Also,
A bearing 27b is provided on an end surface of the operation shaft 27a.

Reference numeral 28 denotes a piston, and a main body forming an inner layer as viewed from the cylinder sliding portion side is formed of an elastic porous body. This includes a foam having a single cell pore (such as a sponge) and a porous body having continuous pores such as a continuous microporous body. Preferably, a continuous microporous body, for example, a continuously foamed urethane foam is used. Can be formed. Further, a plurality of continuous pores may be present in a direction crossing the direction of elastic deformation.
The outer diameter is formed to be larger than the inner diameter of the cylinder 24 by a predetermined amount, and when inserted into the cylinder 24, it is in a state of being appropriately compressed. Further, the outer peripheral surface 28a and the piston shaft 2
The end surface 28b which comes into contact with the piston retainer 27b of No. 7 is adapted to position a solid layer (skin film) at the time of foam molding of the piston. Here, even if the member constituting the piston body communicates and foams, the skin film does not communicate with the liquid and the airtightness is maintained, so that the piston 28 fulfills its function. In addition, as long as it does not have a skin film, a film for maintaining airtightness may be separately provided.

42 is a pump room. Reference numeral 29 denotes a piston pressing roller, which is rotatably attached to the end of the piston shaft 27.
Reference numeral 30 denotes a piston return roller, which is similarly rotatably attached to the end of the piston shaft 27. 31 is the axis of those rollers.

Reference numeral 32 denotes a cap lever, on which a rotary shaft 32a, an ink guide 32b, and a lever guide 32c are formed. Also,
A convex spherical sealing surface 32d is formed at the tip end. Further, an engaging portion 32e for engaging a claw of a cap holder described later is provided as a pair of upper and lower members. Further, the ink flow path 32f passes through the inside of the lever from the sealing surface 32d, turns rightward on the way, passes through the center of the ink guide 32b, and opens at its end face. A notch 32g is provided below the ink guide 32b.

Reference numeral 33 denotes a lever seal, into which the ink guide 32b is fitted and which is pressed into the cap lever receiver 24d. A communication hole 33a communicates the notch 32g of the ink guide 32b with the ink flow path 24e.

Reference numeral 34 denotes a cap holder, which is provided at a position facing a hook 34a that engages with the engaging portion 32e of the cap lever 32. 34b is an opening for attaching a cap described later.

Reference numeral 35 denotes a cap, on which a sealing cap 35a for preventing normal drying of the ink is formed, and adjacent thereto, a suction cap 35b for suction is formed. A suction port 35c is formed in the suction cap 35b, the ink flow path is bent in the cap, and the suction port 35c is opened toward the cap holder 34 through the center thereof.

Reference numeral 35d denotes a flange portion, which serves as a stopper when attached to the cap holder 34. Further, the flange portion 35d is formed with a concave spherical cap seal portion 35e having the same curvature as the sealing surface 32d of the cap lever 32, and only the central opening communicates when pressed against the cap lever 32. Others are sealed. Since the seal portions (32d, 35e) have a spherical shape, the cap member has an excellent ecological function, and even when there is a step on the discharge port forming surface (see FIGS. 24 (B) and (C)). The step can be immediately absorbed to maintain a stable sealed state.

Referring again to FIG. 1, reference numeral 36 denotes a paper feed roller for conveying a recording medium such as paper, and is formed by applying an elastic paint (urethane resin or the like) to the surface of, for example, an aluminum drawing tube. be able to. The roller 36 functions as a platen on its outer surface to regulate the recording surface of the recording medium, and its inside serves as a waste ink storage section. Numeral 37 denotes a waste ink absorbing portion provided inside the roller 36, which is formed by filling a thin tube made of plastic such as vinyl chloride with an absorbing material such as polyester cotton so that ink can be absorbed well in the axial direction. The waste ink tube 24g of the cylinder 24 is inserted and fixed in the waste ink absorbing section 37. Further, the fiber itself of the absorbing material is preferably a non-absorbing material such as resin or metal, but may be slightly absorbing.

Reference numeral 38 denotes a paper holding plate, which is attached to the chassis 1.
A paper feed motor 39 is connected to the paper feed roller 36 via a speed reduction mechanism having a predetermined ratio.

 Reference numeral 40 denotes a recording medium such as paper or film.

Reference numeral 41 denotes a detection unit for detecting the home position of the carrier, which is configured using a transmission type photo interrupter in this example. That is, the position of the carrier can be detected by the detection piece 6b of the carrier 6 blocking the optical path.

 Next, the operation of the above configuration will be described.

First, during a normal recording operation, the rotation of the shaft of the carrier motor 11 rotates the lead screw 2 via the timing belt 13, so that the carrier 6 is moved in the print digit direction by the lead pin 7 engaged with the lead groove 2a. Are scanned along. Here, the carrier motor 11 is a motor spring
The timing belt 13 is always tensioned because it is urged by 14, and good transmission is performed.

When the carrier 6 is moved, an inertial force acts at the time of starting and stopping, but the weight of the carrier motor 11 becomes inertial, so that the load on the motor spring 14 is small and the motor load is small. If an air damper or a hydraulic damper is provided in connection with this spring, noise due to vibration of the rotor of the motor 11 when the carrier 6 starts and stops can be reduced. By appropriately selecting the weight of the motor, the weight of the carrier portion, and the coefficient of the motor spring damper, the overshoot of the rotor can be reduced, and the noise can be reduced.

Next, with reference to FIGS. 5 to 9, the operation of this embodiment during non-recording will be described. FIG. 5 is a timing chart showing the operation timing of each unit. The operation timing of each unit as shown can be determined by the number of pulses applied to the motor 11. In addition, FIG.
FIG. 7C is an explanatory view showing the sequential operation state of each part near the home position, and FIGS.
8 (A) to 8 (C) are explanatory views showing sequential operation states of the mechanism relating to the cap 35, and FIGS. 9 (A) and 9 (B) are explanatory views showing sequential operation states of the mechanism relating to the cap 35. FIG. 4 is an explanatory diagram for explaining an operation of a mechanism for introducing waste ink into a waste ink storage portion 37 in a roller 36.

First, the carrier 6 moves in the home position direction (the direction of arrow B) and is detected by the home position detector 41 (this position may coincide with the start position at the time of wrap-up during recording). At this time, FIG.
As shown in FIG. 7, the lead pin 7 is engaged with the lead groove 2a, and the ejection port 9c of the head element 9a is
(See FIG. 7A). here,
At this position, all of the ejection energy generating elements of the head element 9a are driven to perform an ejection operation (hereinafter, referred to as preliminary ejection), and the slightly thickened ink or the like is ejected with the ejection force,
The recovery operation by this preliminary ejection can be completed. Preliminary ejection is also performed at this position, which is performed periodically to prevent the ink in the unused ejection ports from being thickened during normal printing. FIG. 7A is a side view of the periphery of the same position.

Further, as shown in FIG. 6 (B), when the lead screw 2 is rotated to move the carrier 6 in the B direction, the clutch gear 4 is pressed by the pressing portion 6a, and is similarly moved in the B direction to move the timing gear 21. Of the drive teeth 21b. Since the clutch gear 4 rotates in synchronization with the lead screw 2, the timing gear 21
It rotates in the direction D as shown in FIG. On the other hand, since the lead pin 7 enters the cap groove 3c from the introduction groove 3e, the carrier 6 does not move even if the lead screw 2 rotates.

When the timing gear 21 rotates in the direction D, the gear portion and the gear portion of the set lever 20 mesh with each other, so that the set lever 20 starts rotating in the E direction. Until this time, since the hook 16c is engaged with the claw of the chassis, only the set lever 20 is rotated, and the blade lever 16 is stopped. While pressing down the rotating piece 18a of the blade shaft 18
Therefore, the blade 17 rotates in the direction G and is set in a state capable of engaging with the discharge port forming surface.

When the timing gear 21 further rotates in the direction D, the set lever 20 and the blade lever 16 further rotate to clean the discharge port forming surface of the head 9 as shown in FIG. 7 (C). At this time, the ink liquid or the like removed by wiping the blade 17 is removed only in one direction, that is, only in the downward direction in this case.
Absorbed or retained at the top of 1a. At this time, the ink carrier 19 starts to come into contact with the ink absorber 23.
When the set lever 20 further rotates, as shown in FIG. 7D, the ink carrier 19 and the blade 17 slide on the surface of the wiping portion 23a of the ink absorber 23 and are received by the ink carrier 19 at the time of preliminary ejection. The ink, dust and the like wiped by the blade 17 from the ejection port forming surface are received by the wiping unit 23a, and ink droplets adhering to the ejection port forming surface are also absorbed. Thereby, the ink absorption capacity of the ink carrier 19 can be maintained for a long time.

Further, the timing gear 21 rotates in the direction D. However, since the stop teeth 20a and 20b of the set lever 20 and the stop cam 21a of the timing gear 21 face and contact with each other, the rotation is restricted and the timing Since the drive teeth of the gear 21 are missing teeth, no rotational force acts.

As described above, since the blade and the absorber holding the ink liquid and the like removed by the blade are the same as the ink receiver at the time of preliminary ejection, it is possible to reduce the size of the apparatus and shorten the time for these recovery operations. it can.

When the timing gear 21 further rotates, the cap cam 21c initially restricts the rotation shaft 32a of the cap lever 32c, and therefore, as shown in FIG. 8A, the cap 35 forms the discharge port of the head element 9a. Stopped at a distance from the surface. Next, when the timing gear 21 is further rotated in the D direction, the cap gear 21c is disengaged from the cap cam 21c, so that the restriction state is released. As shown in FIG.
The rotation lever 24f of 24 is urged by the spring portion 22b of the ink absorber spring 22, the cylinder 24 rotates in the F direction, the closed cap 35a of the cap 35 comes into pressure contact with the ejection port forming surface, and the cap operation is started. finish. FIG. 6B shows a top view at this time. At this time, the sealing surface 32d and the cap seal portion 35e are also tightly sealed by the pressing force of the cap.

Well, the above is the nozzle surface cleaning and cap operation,
Usually, the operation is stopped here and the above operation is performed in reverse according to the input of the next recording signal, and the recording operation is started.

Next, a description will be given of a suction recovery operation performed in a case where the ejection state is not improved even by the preliminary ejection.

When this is started, the timing gear 21 is further rotated from the cap position, and the cap lever 32 is pressed by the cap cam 21b to weaken the cap 35 away from the discharge port forming surface as shown in FIG. 8 (C). .

Next, since the lead pin 7 passes through the connection groove 3d and moves to the pump groove 3c, the carrier 6 moves in the B direction by a predetermined amount (the distance between the cap groove and the pump groove).

When the timing gear 21 further rotates in the direction D, it comes off the cap cam 21d again, so that the cap 35 is pressed against the discharge port forming surface. At this time, since the recording head 9 is moving, the ejection port forming surface is capped by the suction cap 35b (see FIG. 6C).

In the present embodiment, as shown in FIG. 6, the ejection port 9c is biased toward the recording area with respect to the ejection port forming surface, and during normal cap without suction, as shown in FIG. 6 (B). Since the entire surface of the cap 35 completely faces the discharge port forming surface, the pressure on each rib of the cap 35 decreases. However, in this case, since it is only necessary to maintain the airtightness with the outside air, there is no problem in preventing drying, and the gap can be sealed with a pressing force of about 10 g. Further, there is an advantage that since the collapse of the rib portion is small, the internal volume of the cap is only slightly reduced and the ink meniscus does not recede at the time of capping.

Further, as shown in FIG. 6 (C), the cap at the time of the recovery process usually has the cap portion removed from the discharge port forming surface.
The pressure is applied only to the rib portion of the recovery cap, and the sealing performance is improved, and thus, the prevention of leakage due to negative pressure is ensured.
At this time, even if the meniscus retreats due to the decrease in the internal capacity of the cap due to the cap, no problem occurs because the meniscus is restored by the suction operation.

Now, with regard to the pump operation, if the recovery operation is started after the above-mentioned closed cap is completed, the suction operation is started.

At this time, first, the piston set cam 21f pushes the piston pressing roller 29 attached to the piston shaft 27 by the rotation of the timing gear 21, so that the piston shaft 27 moves in the H direction as shown in FIG. 9 (A). I do. And the piston
28 is pressed by the piston presser 27b and moves in the H direction, and the pump chamber 42 is in a negative pressure state. Since there is a skin layer on the outer periphery of the piston 28 and the contact surface with the piston retainer 27b, the ink does not leak through the communication hole of the foam material.

Further, since the ink flow path 24e of the cylinder 24 is closed by the piston 28, the piston 28 is in a movable state only by increasing the negative pressure of the pump chamber 42. On the other hand, as shown in FIG. 9 (A), the ink flow path 24e is opened after the above-mentioned re-capping, so that the cap 3 is closed as shown in FIG. 6 (C).
The ink of the head 9 is sucked from the suction port 35c of No. 5. The sucked ink passes through the ink passage 32f formed inside the cap lever 32, passes through the communication hole of the lever seal 33,
Further, through the ink passage 24e of the cylinder 24, the pump chamber 4
Flow into 2.

When the timing gear 21 further rotates, the cap 35 is again slightly separated from the discharge port forming surface by the cap cam 21e, and the ink in the discharge port forming surface and the suction cap 35b is sucked by the remaining negative pressure in the pump chamber, and these portions are sucked. Eliminate ink residue.

Next, when the timing gear 21 is rotated in the opposite direction (the direction shown by the central arrow I in FIG. 7D), the piston reset cam 21g pulls the piston return roller 30, and as shown in FIG. 9B. Then, the fixie shaft 27 is moved in the direction of arrow J. At this time, since the piston 28 moves after the piston receiver 27c of the piston shaft 27 contacts, the end surface 28b of the piston 28
A gap .DELTA.1 is generated between the piston and the piston presser 27b.

The waste ink sucked into the pinch chamber 42 by the movement of the piston shaft 27 and the piston 28 passes through the gap Δl described above, passes through the groove 27f of the piston shaft, and passes through the ink flow path 24c of the cylinder 24. Then, the waste ink is discharged to the vicinity of the center of the waste ink absorber 37 through the waste ink tube 24g. In addition,
At this time, since the ink flow path 24e of the cylinder 24 is closed by the piston 28 at the beginning of the operation of the piston 28, the waste ink does not flow backward in the cap direction.

FIG. 10 shows the sequence of the above preliminary ejection or suction recovery. However, in the figure, blade 17
Waits in a state in which wiping is possible (set state; see FIG. 7B), and after wiping, the blade 17
(Reset state; see FIG. 7 (A))
Then, a sequence is shown in which the blade 17 is set to a set state in which wiping is possible immediately before the set lever 20 returns to the original position.

Note that the present invention is not limited to the above-described configuration, and can adopt various configurations. Therefore, other embodiments of the above-described units will be exemplified.

FIG. 11 shows another embodiment of the blade and the ink carrier portion. The ink carrier main body 119 according to the present embodiment is formed of an elastic member such as rubber, and the ink receiving portion 119a having the same function as the above-described ink carrier 19 has a large number of grooves or irregularities. Then, the ink is held at the surface tension and transported to the ink absorber 23.
Further, a blade 119b for wiping the ejection port forming surface 9a of the head 9 is formed integrally with the main body of the ink carrier 119. According to this, since the ink carrier main body 119 can be provided directly on the set lever 20, the blade lever
16 is also unnecessary, the number of parts can be reduced, and the apparatus can be constructed at low cost.

When the discharge direction is downward, the blade 119b
The ink on the ejection port forming surface when the wiping is performed is received by the groove or the unevenness, and does not flow out to other mechanism parts, thereby preventing contamination of the device.

FIG. 12 shows still another embodiment of the blade and the ink carrier portion. In this example, the ink carrier 219 is stretched to be integrated with the ink absorber 219c. In this case, a flexible woven fabric, laminated paper, or the like is particularly preferably used as a forming material.

In the present embodiment, the above-described ink absorber 23 and its holding member are not required, and the ink absorber 23 and the holding member can be widely disposed below the chassis.

FIG. 13 shows another embodiment of the piston portion. In the piston 128 according to the present embodiment, the skin layer 150 is not made to exist on the end face, and a flange 151 as shown in the drawing is provided on the piston retainer 127 to hold the piston 128 in a narrowed state. With such a configuration, not only the airtightness is maintained, but also the cost can be reduced because the piston 128 can be manufactured by cutting a long piston material.

FIG. 14 shows still another embodiment of the piston portion. The piston 228 according to the present example is formed of a plate-shaped member. Such a piston is shielded in the thickness direction of the skin layer (253) and can be easily manufactured by pressing or the like, so that the manufacturing cost can be further reduced.

FIG. 15 shows still another embodiment of the rear portion of the cap portion 35. In this example, a rib 35e is provided on the sealing surface 35d so that the airtightness is further secured by deformation of the rib portion.

FIG. 16 shows still another embodiment of the rear portion of the cap portion 35. In this embodiment, a spherical seal portion 35d and a protective seal portion 35f covering the seal portion 35d are provided. According to the present example, when the cap is not capped, the spherical seal portion 35 described above is used.
It is possible to prevent the sealing performance from deteriorating due to sticking of the ink to d or mixing of dust.

FIG. 17 shows still another embodiment of the rear portion of the cap portion. This example shows a cap lever that holds the cap 35
Spherical seal 3 at the connection between 332 and pump cylinder 24
50 are provided, and all the seal portions of the ink flow path are pressed and sealed with the same spring force. According to this, the operating force of the entire recovery system can be reduced.

FIG. 18 shows another embodiment of the waste ink storage section disposed inside the roller 36 as the transport means. In this example, a guide member 160 is attached to the end of the waste ink absorber 137. According to this, the frictional force on the inner surface of the paper feed roller 36 is reduced,
The load on the paper feed motor 39 can be reduced.

FIG. 19 shows still another embodiment of the waste ink absorbing section.
A hollow shaft 261 penetrates the center of the waste ink absorber 237 according to the present example, and the end and the center of the hollow shaft 261 include:
Openings 262 and 263 are provided, respectively. Also 26
4 is a lid.

In this example, the waste ink passes through the hollow shaft 261 and the hollow shaft 261 can also function as a guide shaft for the paper feed roller 36. In this case, there is no sliding portion on the paper feed roller, and the load on the paper feed motor is further reduced.

In this example, the main ink discharge portion 263 is provided in the central region in the longitudinal direction of the platen roller. However, with respect to the ink guide member, the second ink discharge portion is located upstream of the discharge portion 263, and the third ink discharge portion is located downstream of the discharge portion 263. An ink discharge unit may be provided. Also, the size of each is smaller than that of the center,
A configuration such as enlarging the latter may be adopted.

FIG. 20 shows still another embodiment of the waste ink absorbing section.
In this example, when manufacturing the waste ink absorber 337, the waste ink tube 365 is inserted into the center of the material 337 ', and after cutting, the tube 365 is pulled out about half and connected to the recovery pump. is there. According to this example, it is possible to eliminate the difficulty of inserting a member having no rigidity such as a flexible tube to the vicinity of the center. At this time, the tube of the half of the waste ink absorber 337 remains pulled out, but when polyester cotton or the like is used, the hole is closed because it is sufficiently compressed.

The waste ink absorbing section is provided inside the roller-shaped transporting means as described above, or may be provided at an appropriate portion inside the transporting means depending on the configuration of the transporting means. For example, in the case where the conveying means is composed of a plurality of rollers and a belt stretched between the rollers, the conveying means may be provided in a space formed by the rollers and the belt.

FIG. 21 shows another embodiment of the cap 35. In this example,
The sealing cap portion 135a is a plate-shaped member so that the discharge port forming surface does not come into contact with air, so that the sealing effect is further improved. In addition, ink flows out from the ejection port due to surface tension, and the ink contacts the outside air around the cap,
In this portion, the viscosity of the ink is increased or fixed, that is, the ink is generated in a portion other than the ejection port. Therefore, a problem hardly occurs in the recording operation after the cap is opened.

FIG. 22 shows still another embodiment of the cap 35. In this example, the closed cap 235a is formed of a single-cell porous block such as urethane foam, so that the sealing cap 235a is in close contact with the unevenness of the discharge port forming surface to improve the adhesion and reduce the pressing force of the cap. Become.

FIG. 23 shows still another embodiment of the cap 35. In this example, a closed cap portion 335a in the form of open-cell urethane foam is used.
The skin layer 335b formed on the main body is formed on the nozzle contact surface, and the cap performance is guaranteed for a long period of time due to the stability of the number of repulsions, which is a feature of the open-cell urethane foam.

FIG. 24 (A) shows another embodiment of the blade. In this example, as shown in FIG. 24 (B) or (C), there is a step on the surface 9d on which the discharge port 9c is formed, and this is also effective when wiping the surface on the back side. That is, in this example, the blade 11
A short fiber 117a made of a polymer material is electrostatically adsorbed and adhered to the entire surface or part of the nozzle that comes into contact with the nozzle surface. In addition, long objects such as thread-like dust can be effectively removed.

FIG. 25 shows still another embodiment of the blade. In this example, the blade 217 is formed in a brush shape, and can be formed by bundling fibers 217b of a polymer material such as plastic. In this example, the cleaning effect is large even when the groove of the discharge port forming surface having a step is deep as shown in FIG. 24 (B) or (C), and the pressing force of the blade against the discharge port forming surface 9d is also large. Is a form in which each hair comes into contact with each other, so that even a small hair is sufficient, and the durability of the surface treatment layer such as a water repellent which may be applied to the discharge port forming surface is not impaired. .

[Effects of the Invention] As is apparent from the above description, according to the present invention, since the elastic porous material layer is provided, foreign matter such as dust adhering to the ejection port surface of the recording head is prevented from being contaminated by the piston shaft surface or Even if it mixes into the seal portion of the cylinder inner surface, the piston itself is partially deformed and the generation of voids due to the presence of foreign matter can be absorbed and the sealing effect can be maintained, resulting in less deterioration in sealing performance and extremely stable A suction operation can be performed.

Further, in the present invention, the durability can be maintained for an extremely long period of time by making the elastic porous body layer a fine continuous porous body, so that this configuration is the optimum mode of the present invention.

Further, by using the elastic porous body for the piston body, the operating force becomes uniform, and a stable suction operation becomes possible.

In addition, a path for discharging waste ink to a waste ink tank is formed in the suction pump along with a suction operation for recovering discharge.

In the suction pump, the piston shaft also serves as a one-way valve.

As a result, a waste ink tube for discharging waste ink is not required, whereby the space occupied by the waste ink tube can be omitted, and the apparatus becomes small and simple.

Further, since the size of the suction pump can be reduced, the size of the apparatus can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of an ink jet printer according to the present invention, FIGS. 2 (A) to 2 (C) are partial perspective views showing an embodiment of a blade and an ink carrier portion for a recording head, FIG. 4 and FIG. 4 are an exploded perspective view and a cross-sectional view, respectively, showing an embodiment of a suction recovery system for a recording head. FIG. 5 is a timing chart showing operation timings of respective parts according to the embodiment. FIGS. 7 (A) to 7 (D) are plan views for explaining the positional relationship between the recording head and members used for the processing during preliminary ejection, capping, and suction recovery. FIGS. 8 (A) to 8 (C) are side views for explaining the sequential operation of the cap and the ink carrier section, and FIGS. 9 (A) and 9 (A) are side views for explaining the sequential operation of the cap section. B) Suction recovery FIG. 10 is a side sectional view for explaining the operation of the pump section for performing the operation. FIG. 10 is a timing chart for explaining a sequence at the time of preliminary discharge or suction recovery processing according to this example (partially another embodiment). And FIG. 12 is a perspective view showing another embodiment of the blade and the ink carrier section. FIGS. 13 and 14 are cross-sectional views showing another embodiment of the piston arranged in the pump section. FIG. 17 to FIG. 17 are explanatory views showing another embodiment of the connection portion in the suction recovery system behind the cap, and FIG. 18 to FIG. 20 are other three embodiments of the waste ink absorbing section arranged in the paper feed roller. 21 to 23 are perspective views showing other three embodiments of the sealing cap portion of the cap, FIGS. 24 (A), (B), (C) and FIG. 25 are blades FIG. 26A is a perspective view for explaining another two embodiments of the present invention, and FIG. External perspective view showing an ink suction arrangement, FIG. 26 (B) is a perspective view showing the piston of the details in the suction pump shown in FIG. (A). 1 ... chassis, 2 ... lead screw, 2a ... lead groove, 3 ... lead pulley, 3b ... cap groove, 3c ...
Pump groove, 4 ... clutch gear, 5 ... clutch spring,
6 Carrier 7 Lead pin 9 Recording head 9a Head chip 9b Ink tank 9c
... discharge port, 9d ... discharge port forming surface, 11 ... carrier motor, 13 ... timing belt, 15 ... set shaft, 16 ...
Blade lever, 17,119b, 117,217 …… Blade, 19,11
9,219 ink carrier, 20 set lever, 21
... Timing gear, 22 ... Ink absorber spring, 23 ... Ink absorber, 24 ... Cylinder, 27 ... Piston shaft, 28 ...
... Piston, 29 ... Piston pressing roller, 32 ... Cap lever, 34 ... Cap holder, 35 ... Cap, 35
a, 135a, 235a, 335a: Sealing cap, 35b: Suction cap, 37, 337: Waste ink absorber, 40: Recording medium,
41: Home position detector, 42: Pump room.

Claims (5)

(57) [Claims] 1. An ink jet recording apparatus comprising: a suction pump for sucking ink from said discharge port of a recording head for performing recording by discharging ink from a discharge port to improve an ink discharge state; And a piston reciprocating in the cylinder, and an elastic porous layer as an inner layer as viewed from a sliding portion of the piston with the cylinder. 2. A solid layer for forming an inner layer of the piston with the elastic porous body at a sliding portion of the piston with respect to the cylinder. Ink jet recording device. 3. The ink jet recording apparatus according to claim 1, wherein the continuous fine porous body forming the piston body is a continuously foamed urethane foam. 4. A piston shaft for reciprocating the piston has flanges disposed on both sides of the piston with a distance exceeding an axial length of the piston to press the piston during the reciprocating motion. 2. An ink jet recording apparatus according to claim 1, wherein an ink flow path is formed on a shaft between the flanges. 5. An ink jet recording apparatus comprising a suction pump for ejecting ink from an ejection port to perform recording by sucking ink from said ejection port of a recording head for improving the ink ejection state. And a piston that reciprocates in the cylinder, and has a layer of an elastic porous body as an inner layer viewed from a sliding portion of the piston with the cylinder, and the piston has a solid layer on the ink suction side. And an ink jet recording apparatus for forming a negative pressure and an ink recovery path.