JPH02194968A - Ink jet recorder - Google Patents

Abstract

PURPOSE:To reduce deterioration of sealing performance and to provide a stable absorbing operation by employing an elastic porous material as a piston body of a pump for discharging waste ink in a suction pump into a waste ink tank, etc. CONSTITUTION:A piston 28 is formed at a body forming an inner layer as seen from a cylinder slide section side of an elastic porous material. It is formed of a continuous fine porous material such as urethane foam foamed in communication. Its outer diameter is formed to be larger in a predetermined amount than the inner diameter of a cylinder 24, and when it is inserted into the cylinder 24, it is suitably compressed. Its outer surface 28a and its end face 28b brought into contact with the piston retainer 27b of a piston shaft 27 are disposed with solid layers (skin layers) at the time of foaming molding. Even if a member forming a piston body is foamed in communicated, manner, the skin film does not permeate liquid and holds sealability. Accordingly, the piston 28 performs the function.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to an inkjet recording device.

[Prior Art] This type of apparatus includes, in addition to the configuration related to direct recording, a configuration specific to a method of recording by ejecting ink.

In other words, depending on the recorded data, if a certain ejection port does not eject for a long time, or if the device 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 may increase due to water evaporation. It may become viscous and cause non-ejection, and it may cause ink droplets,
Water droplets, dust, etc. may adhere, and the ejected ink droplets may be pulled by these adhering substances, causing the ejection direction to be deflected. For this reason, inkjet recording apparatuses include various configurations as so-called ejection recovery systems in order to prevent ejection failure and deflection of the ejection direction.

These ejection recovery systems are configured to prevent ejection failures, such as preliminary ejection that ejects ink onto a predetermined ink receiving medium to remove thickened ink, and suction of ink from the ejection port or ink chamber to remove the above. There is ink suction that performs this, and capping that seals the ejection port surface to prevent ink moisture from evaporating from the ejection port.

Further, as a structure for preventing deflection of the ejection direction, there is a structure in which the ejection port surface is wiped to remove dust, ink droplets, etc. adhering to the vicinity of the ejection port.

On the other hand, in recent years, inkjet recording devices, particularly recording heads, have been manufactured using semiconductor film forming processes and microfabrication techniques, and smaller and cheaper recording heads are being realized. This results in
For example, a disposable type recording head with an integrated ink tank has also been proposed.

As a result, there is a demand for an inkjet recording apparatus that is compact and inexpensive, and that is easier for users to use.

[Problems to be Solved by the Invention] By the way, there are various problems to be solved in order to realize the above-mentioned inkjet recording apparatus, particularly an apparatus that is small, inexpensive, and compatible with a disposable type of recording head.

These problems mainly exist in the configuration for ejection recovery described above, and miniaturization of the apparatus is hindered by the space required to provide devices for preliminary ejection, ink suction, and capping.

Moreover, the space required for a waste ink tank for storing waste ink resulting from preliminary ejection and suction, a suction pump for guiding the waste ink to the tank, a tube, etc. also impedes miniaturization of the apparatus.

Among the configurations of the recovery system described above, the configuration that specifically performs ink suction has conventionally been composed of a cap 100 for capping the ink ejection port surface and a pump 101 for suctioning the ink, as shown in FIG. 26(^), for example. , a connecting tube 102 for connecting a cap 100 and a pump 101. Further, as shown in FIG. 26 ([1)], the pump 101 has a structure in which a one-way valve 104 is provided on the end surface of the shaft of the piston 103 to perform suction and discharge. Note that the periphery of this -direction valve is made of a substance such as rubber.

However, in the conventional recovery system described above, the cap 100
Since a connecting tube 102 from the pump 101 to the waste ink tank 101 and a drain tube 106 from the pump 101 to the waste ink tank 105 are required, the configuration of these devices becomes complicated, and space is required to arrange the tubes. There was a problem with that.

Furthermore, the presence of the tube increases the evaporation of ink water from the tube, resulting in thickening of the ink inside the tube and near the ejection port, which may eventually stick.

Furthermore, since the one-way valve is provided on the piston shaft, a certain amount of area is required at the end of the piston shaft where the valve is disposed. For this reason, there was a problem in that the diameter of the piston became large, and as a result, the pump itself became large. In addition, in this pump, the solid rubber that is generally used to form the body of the piston has a large load when deformed, so the operating force of the piston becomes uneven, making it impossible to perform stable suction operation. was there. Also,
Solid rubber pistons have poor durability and do not have the ability to tolerate dust and the like that enter through suction, resulting in a significant reduction in suction effectiveness.

The present invention has been made in view of the above-mentioned problems regarding the configuration of an ink suction pump during ejection recovery, and its main purpose is to solve the above problems regarding the piston, which is a component of the pump for suction. An object of the present invention is to provide an inkjet recording device that has the following features.

[Means for Solving the Problems] To this end, the present invention provides an inkjet equipped with a suction pump that suctions ink from the ejection port of a recording head that performs printing by ejecting ink from the ejection port to improve the ink ejection state. In the recording device, the suction pump has a cylinder and a piston that reciprocates within the cylinder, and is characterized in that it has a layer of an elastic porous material as an inner layer when viewed from a sliding portion of the piston and the cylinder.

In another aspect of the present invention, an inkjet recording apparatus includes a suction pump that suctions ink from an ejection port of a print head that performs printing by ejecting ink from an ejection port to improve the ink ejection state. The pump has a cylinder and a piston that reciprocates within the cylinder, and has an elastic porous layer as an inner layer when viewed from the sliding part of the piston with the cylinder, and the piston has a solid layer on the ink suction side. It is characterized by forming a negative pressure and forming an ink recovery path.

[Function] According to the above configuration, an elastic porous body is used in the piston body of the pump for discharging waste ink into the waste ink tank or the like within the suction pump during the suction operation for ejection recovery. , the operating force can be made uniform.

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

[Example] 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 device (inkjet printer) according to an embodiment of the present invention, and Fig. 2 (^
) to (C) are partial perspective views for explaining each part of means for improving the ejection orifice forming surface of the recording head disposed in the printer, FIG. 3 is an exploded perspective view of the recovery system, and FIG. FIG. 4 is a sectional view of the pump section.

First, in FIG. 1, reference numeral 1 denotes a chassis, and a left side plate 1a and a right side plate ib, which also serve as guides for recording media such as paper, are erected on the rear side. Further, a front side plate 1c is erected at the right end, and a carrier guide plate 1d is erected at the front side. le is a long hole for guiding the carrier,
A carrier guide roller, which will be described later, fits and slides. The chassis 1 is provided with a motor mounting hole for rotatably supporting a carrier motor, which will be described later, but is not shown.

lh is a lead arm that supports a lead screw, which will be described later, in the axial and radial directions, and is a bearing part (not shown).
It is pivoted on.

2 is a lead screw, and lead grooves 2a are formed at a predetermined pitch facing the recording range. Further, on the carrier home position side of the lead screw 2, a cap groove 3b for setting the cap position and a pump groove 30 for setting the recovery position are formed along a cross section perpendicular to the axis. Groove 3
c is smoothly continuous with the connecting groove 3d. Furthermore, the lead groove 2a and the cap groove 3b are similarly introduced into the introduction groove 3e.
It continues smoothly.

A shaft 28 is provided at the right end of the lead screw 2, and a shaft is also provided at the left end, which are fitted into bearings provided on the front plate 1c and the lead arm lb, respectively.
It is rotatably supported relative to them. 3 is the groove 3b mentioned above.
~3e, which is provided on the shaft of the lead screw 2, and has a pulley 3a at its end. A driving force is transmitted from the motor 11 to the pulley 3a via the timing belt 13. Further, the shaft 2g on the right end side of the lead screw 2 is pressed in the thrust direction by a plate spring or the like (not shown).

A clutch gear 4 is slidably supported by the lead pulley 3 in the axial direction, and is engaged in the rotational direction with a detent (not shown) so that the rotational force of the lead screw 2 is transmitted. A clutch spring 5 is a compression spring that biases the clutch gear 4 in the direction of the lead groove. Note that the clutch gear 4 and the lead pulley 3 are the regulating members that prevent the clutch gear 4 from moving only within a predetermined range.
Although it is formed between the two, the illustration is omitted.

A carrier 6 is slidably attached to the lead screw 2. 6a is a pressing portion for pressing the end face of the clutch gear 4, and is integrally formed on the left side of the carrier. 6b is a detection piece for detecting the home position of the carrier 6. A lead pin 7 engages with a lead groove 28 of the lead screw 2 and is guided through a guide hole (not shown) of the carrier 6. A lead pin spring 8 has one end attached to the carrier 6 and presses the lead pin 7 with the other end.

Reference numeral 9 denotes a recording head mounted on the carrier 6, and in this example, a cartridge is formed in which a head element 9a for ejecting ink and an ink tank 9b serving as an ink supply source are integrated and can be attached to and detached from the carrier 6. It is a disposable type that can be replaced when the ink is consumed. Note that an electrothermal transducer or an electromechanical transducer is used as the ejection energy generating element disposed in the head element 9a to apply ejection energy to the ink, but it is possible to implement high-density mounting of ink ejection ports, etc. There is something
The former is preferably used because the manufacturing process is simple.

A carrier roller 10 is rotatably attached to the rear end surface of the carrier 6, and is rotatably engaged with the long hole 1e of the chassis 1 described above.

Reference numeral 11 denotes a carrier motor composed of, for example, a pulse motor, and rotary bins 11a are provided in alignment at the lower part of the front and rear surfaces of the carrier motor. ) is chassis 1
It is rotatably attached to the motor mounting hole provided in the The carrier motor 11 is rotatably mounted around the rotation bin lla. llb is a spring receiver, which is integrally formed with the carrier motor 11 and is erected in parallel with the motor shaft to receive a motor spring 14, which will be described later. A cylindrical projection is formed on the spring receiver, and the end of the coiled motor spring 14 is fixed thereto.

Reference numeral 12 denotes a motor pulley, which is fixed to the motor shaft of the carrier motor 11. A timing belt 13 is stretched between the motor pulley 12 and a pulley 3a provided on the shaft of the lead screw 2.

The motor spring 14 is a compression spring in the configuration of this example, and is attached between one end of the lead arm 1h and the spring receiver llb of the carrier motor 11, thereby causing the carrier motor 11 to rotate in the direction shown in the figure. When 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, to which a means for improving the discharge port forming surface, a cap, and a mechanism related to discharge recovery are attached.

Means for improving the discharge port forming surface will be explained using FIG. 1 and FIGS. 2 (^) to (C).

16 is a blade lever (see FIG. 2(A)), and a boss portion 16a is rotatably attached to the set shaft 15. 16b is an arm portion, and 16C is a hook portion. Reference numeral 17 denotes a blade for wiping the surface on which the discharge port is formed, and can be made of an elastic member such as silicone rubber or chloroprene (CR) rubber. Reference numeral 18 denotes a blade shaft, which clamps the blade 17 at the center parallel to the rotating shaft, and is rotatably attached to the blade lever 16. Moreover, 18a is a rotating piece, which is formed integrally with the blade shaft 18. 19 is an ink carrier, which is a hydrophilic porous material (plastic sintered body, urethane foam, etc.)
It is fixed to the blade lever 16. Note that the blade 17 and the ink carrier 19 are
It is arranged at a position overlapping with a cap which will be described later.

20 is a set lever, which is rotatably attached to the set shaft 15. 20a and 20b are stop teeth provided on the set lever 20, and 20c is a start tooth.

Reference numeral 20d is also a rotating tooth, and the thickness of the start tooth 20c is approximately half that of the other teeth. 20e is an arm part, and by cutting a part of it in the plate thickness direction, a setting surface 20f is formed.
A rotating piece 18 of the blade shaft 18 attached to the blade lever 16 is formed with a reset surface 20g.
a is fitted and combined to drive it.

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

As shown in FIG. 2(B), the timing gear 21 has stop teeth 20a, 2 of the set lever 20 described above on a part of its outer periphery.
A stop cam 21a is formed for engaging 0b. Moreover, the drive teeth 21bl are partially missing teeth.

21b2. ... are formed, and cap cams 21c to 21e for swinging the cap lever described later.
is formed in a predetermined position. In addition, a piston set cam 21 for pressing the piston of the pump, which will be described later.
f is formed as a face cam, and a piston reset cam 21g is integrally formed at a predetermined interval in correspondence with 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.
2b. Reference numeral 23 denotes an ink absorber, which is made of a hydrophilic porous material like the ink carrier 19 described above. This ink absorber 23 is formed with a wiping portion 23a that the blade 17 mentioned above comes into contact with.
Furthermore, an absorbing portion 23b is formed in the lower portion, with which the ink carrier 19 mentioned above contacts and receives and transfers ink. The absorber holding portion of the ink absorber spring 22 is biased upward with some elastic force, and is locked in a predetermined position by a stopper (not shown). Therefore, when the above-mentioned ink carrier 19 comes into contact with the ink absorber 23, the ink absorber spring 22 is bent and the ink absorber 23 is displaced downward, thereby ensuring the contact state.

Next, the recovery system unit will be described mainly with reference to FIGS. 3 and 4.

In FIGS. 3 and 4, 24 is a cylinder;
It has a cylindrical cylinder part 24a and a guide part 24b that guides a piston shaft, which will be described later.
b has an ink flow path 24 by cutting out a part in the axial direction.
It forms c. 24d is a cap lever receiver, which is formed so that a lever seal, which will be described later, is fitted therein. Further, 24e is an ink flow path, which opens at a predetermined position within the cylinder portion 4a. Reference numeral 24f denotes a rotating lever, which is formed integrally with the cylinder 24 and is provided with a rotating force by the spring portion 22b of the ink absorber spring 22 described above. A waste ink pipe 248 is formed integrally with the cylinder 24, and its tip is cut into an acute angle so that it can be easily inserted into a waste ink absorber to be described later. 24b is an ink flow path formed within the waste ink pipe 24g.

25 is a cylinder gap, which is press-fitted into the end of the cylinder 24. , 25a is a lever guide, which is disposed at a position facing the cap lever receiver 24d of the cylinder 24 mentioned above.

A piston seal 26 is fitted into the cylinder 24, and its inner diameter is made slightly smaller so as to obtain a predetermined pressure contact with the piston shaft, which will be described later. Further, the sliding force of the piston shaft may be reduced by applying a lubricating coating to the surface.

27 is a piston shaft, which is formed with an operating shaft 27a, a piston presser 27b, a piston receiver 27c, a connecting shaft 27d, and a guide φ1h27e, and m27f, which serves as an ink flow path, is connected to a connecting @1127d and a guide ITl.
It is formed along h27e. 27g is a rotation stopper, which is formed as a groove on the operating shaft 27a. Further, a bearing portion 27b is provided on the end surface of the operating shaft 27a.

28 is a piston, and the main body forming the inner layer when viewed from the cylinder sliding part side is formed of an elastic porous material. This includes foams with single pores (such as sponges) and porous bodies with continuous pores such as continuous microporous materials, but preferably continuous microporous materials, such as open-cell foamed urethane foam. Can be formed. Further, a plurality of continuous pores may exist in a direction crossing the direction of elastic deformation.

The outer diameter thereof 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 an appropriately compressed state. Also, the outer peripheral surface 28a and the end surface 28b of the piston shaft 27 that comes into contact with the piston presser 27b.
is the solid layer (skin III) during foam molding of the piston.
This is how you position it.

Here, even if the member forming the piston body is foamed and communicated, the skin film does not communicate with liquid and maintains airtightness, so 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 chamber. 29 is a piston suppression roller, which is rotatably attached to the end of the piston @27. 30 is a piston return roller, which is similarly rotatably attached to the end of the piston shaft 27. 31 is the axis of these rollers.

32 is a cap lever, and a rotating shaft 32a5, an ink guide 32b and a lever guide 32c are formed. In addition, the tip has a convex spherical sealing surface 32d.
is formed. Further, an engaging portion 32e for engaging with a claw of a cap holder, which will be 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, bends at a right angle halfway, passes through the center of the ink guide 32b, and opens at the end surface thereof. Note that a cutout 32g is provided on the lower side of the ink guide 32b.

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

34 is a cap holder, and a hook 34a that engages with the engaging portion 32a of the cap lever 32 is provided at an opposing position. 34b is an opening for attaching a cap, which will be described later.

Reference numeral 35 designates a cap, in which a sealing cap 35a for preventing normal ink from drying is formed, and a suction cap 35b for suction is formed adjacent to this. A suction port 35c is formed in the suction cap 35b, bending the ink flow path within the cap, and opening toward the cap holder 34 through the center thereof.

35d is a flange portion, which prevents the cap from coming off 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 the cap lever 32 is pressed. Everything else is sealed. And the seal part (32d).

35e) has a spherical shape, so the cap member has an excellent equalization function, and even if there is a step on the discharge port forming surface (see Fig. 24 (B) and (C)), the cap member can immediately absorb the step. can maintain a stable sealed state.

Now, referring again to FIG. 1, 36 is a paper feed roller for conveying a recording medium such as paper, and is formed by applying an elastic paint (urethane resin, etc.) to the surface of a drawn aluminum tube, for example. be able to. Also, this roller 36
The platen functions on its outer surface as a platen that regulates the recording surface of the recording medium, and its interior serves as a storage section for waste ink. 37 is a waste ink absorbing section provided inside the roller 36, in which a tube made of a thin plastic such as vinyl chloride is filled with an absorbing material such as polyester cotton;
It has a structure that allows for good ink absorption in the axial direction. Note that the waste ink pipe 2/2 of the cylinder 24 is inside the waste ink absorbing section 37.
Ig is inserted and secured. Furthermore, the fibers of the absorbent material themselves are preferably made of a non-liquid-absorbing material such as resin or metal, but may be slightly liquid-absorbing.

38 is a paper press plate, which is attached to the chassis 1.

Reference numeral 39 denotes a paper feed motor, which is connected to the paper feed roller 36 via a speed reduction mechanism with a predetermined ratio.

40 is a recording medium such as paper or film.

Reference numeral 41 denotes a detector for detecting the home position of the carrier, and in this example, it is configured using a transmission type photointerrupter. That is, the detection piece 6b of the carrier 6
The position of the carrier can be detected by blocking the optical path.

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

First, during normal recording operation, the rotation of the shaft of the carrier motor 11 rotates the lead screw 2 via the timing belt 13, so the carrier 6 is moved toward the printing digit direction by the lead bin 7 engaged with the lead groove 2a toward the recording medium 40.
scanned along. Here, since the carrier motor 11 is biased by the motor spring 14, the timing belt 13 is always tensioned and good transmission is achieved.

When moving the carrier 6, an inertial force acts at the time of starting and stopping, but since the weight of the carrier motor 11 acts as inertia, the load on the motor spring 14 can be reduced, and the motor load can also be reduced. Further, if an air damper, a hydraulic damper, or the like is provided in connection with this spring, noise caused by vibration of the rotor of the motor 11 when the carrier 6 is started or stopped 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, overshoot of the rotor can be reduced and noise can be reduced.

Next, the operation of this embodiment during non-recording will be described with reference to FIGS. 5 to 9. Note that FIG. 5 is a timing chart showing the operation timing of each part, and the operation timing of each part as shown can be determined by the number of pulses applied to the motor 11. Also, Figure 6 (^) ~ (C
) is an explanatory diagram showing the sequential operating states of each part near the home position, FIGS. 7(^) to (D) are explanatory diagrams showing the sequential operating states of mechanisms related to the blade 17, etc.
) to (C) are explanatory diagrams showing the sequential operating states of the mechanism related to the cap 35, and FIGS. FIG.

First, the carrier 6 moves in the direction of the home position (in 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. 6 (A)
As shown in FIG. 7, the lead bin 7 is engaged with the lead groove 28, and the ejection port 9c of the head element 9a is located at a position facing the ink carrier 19 (see FIG. 7(A)). 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 slightly thickened ink, etc. is ejected with that ejection force, and recovery is achieved by this preliminary ejection. The operation can be terminated. Preliminary ejection is also performed at this position, which is periodically performed to prevent the ink in unused ejection ports from increasing in viscosity during normal printing. In addition, FIG. 7 (^) is a side view of the vicinity of the same position.

Further, as shown in FIG. 6(B), when the lead screw 2 is rotated and the carrier 6 is moved in the direction B, the clutch gear 4 is pressed by the pressing part 6a, and the clutch gear 4 is also moved in the direction B and the timing gear 21 is moved. meshes with the drive teeth 21b. Since the clutch gear 4 rotates in synchronization with the lead screw 2, as the motor 11 is driven, the timing gear 21 rotates in the D direction as shown in FIG. 7(8). On the other hand, the lead pin 7 is inserted from the introduction groove 3e to the cap groove 3C.
Since the lead screw 2 is inserted into the lead screw 2, the carrier 6 does not move even when the lead screw 2 rotates.

When the timing gear 21 rotates in the D direction, the set lever 20 begins to rotate in the E direction because its gear portion and the gear portion of the set lever 20 are engaged with each other. Until this time, the hook portion 16c of the blade lever 16 is engaged with the claw portion of the chassis, so only the set lever 20 rotates.
Although the blade lever 18 is stopped, the setting surface 2Of of the set lever 20 eventually reaches the blade axis! Since the blade 17 rotates in the F direction while pushing down the rotary piece 18a of No. 8, the blade 17 rotates in the G direction and is set in a state where it can engage with the discharge port forming surface.

When the timing gear 21 further rotates in the D direction, the set lever 20 and the blade lever 16 also rotate further, thereby wiping the discharge port forming surface of the head 9 as shown in FIG. 7(C). At this time, the ink liquid and the like that are removed by wiping the plate 17 are removed only in one direction, that is, only downward in this case, and the removed ink liquid and the like are absorbed or retained in the upper part of the ink carrier la. Also,
After this, the ink carrier 19 begins to come into contact with the ink absorber 23 . When the set lever 20 further rotates, the ink carrier 19 and blade 17 slide against the surface of the wiping portion 23a of the ink absorber 23, as shown in FIG. The wiping part 23a receives the ink and dust wiped by the blade 17 from the ejection port forming surface, and
Ink droplets adhering to the ejection port forming surface are also absorbed. Thereby, the ink absorbing ability of the ink carrier 19 can be maintained for a long period of time.

Further, the timing gear 21 rotates in the D direction, but since the stop teeth 20a, 20b of the set lever 20 and the stop cam 21a of the timing gear 21 face each other and come into contact with each other, the rotation is restricted and at the same time the timing Since the drive teeth of the gear 21 are missing teeth, no rotation force is applied.

As mentioned above, since the blade and the absorber that holds the ink liquid etc. removed by the blade are the same as the ink receiver during preliminary ejection, the device can be made smaller and the time required for these recovery operations can be shortened. can.

When the timing gear 21 rotates further, the cap cam 21c initially restricts the rotating shaft 32a of the cap lever 32c, so the cap 35 moves to form the discharge port of the head element 9a, as shown in FIG. 8(^). It is stopped at a distance from the surface. Next, when the timing gear 21 roughly rotates in the D direction, it comes off the cap cam 21c and the restriction state is released, so that the rotation lever 24f of the cylinder 24 is The cylinder 24 is biased by the spring portion 22b of the absorber spring 22 and rotates in the F direction, and the sealing cap 3 of the cap 35 is rotated.
5a comes into pressure contact with the discharge port forming surface, and the capping operation is completed. Note that FIG. 6(B) shows a top view at this time. At this time, the seal surface 32d and the cap seal portion 35e are also tightly sealed due to the pressing force of the cap.

Now, the above is the cleaning and capping operation of the nozzle surface, and normally the apparatus stops here, performs the above operation in reverse according to the input of the next recording signal, and then starts the recording operation.

Next, a suction recovery operation that is performed when the ejection condition is not improved even after preliminary ejection will be described.

When starting this, the timing gear 21 is further rotated from the cap position, and the cap lever 32 is pressed by the cap cam 21b, so that the cap 35 is weakened and separated from the discharge port forming surface as shown in FIG. 8(C). .

Next, the lead pin 7 passes through the connection 13d and the pump groove 30
Therefore, the carrier 6 moves in the B direction by a predetermined amount (distance wi between the cap groove and the pump groove).

When the timing gear 21 rotates roughly in the D direction, it comes off again from the cap cam 21d, so that the cap 35 comes into pressure contact with the discharge port forming surface. Since the recording head 9 is moving at this time, the ejection port forming surface is capped by the suction cap 35b (see FIG. 6(C)).

In this embodiment, as shown in FIG. 6, the ejection port 9C is biased toward the recording area side with respect to the ejection port forming surface, and during normal capping 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 applied to each rib portion of the cap 35 is reduced. However, in this case, it is only necessary to maintain airtightness with the outside air, so there is no problem in preventing dryness, and the gap can be sealed with a pressing force of about 10 g. Further, since the rib portion is less crushed, the internal volume of the cap is only slightly reduced, and there is an advantage that the ink meniscus does not recede during capping.

Furthermore, as shown in Figure 6 (C), during the recovery process, the cap part normally comes off from the discharge port forming surface, so pressure is applied only to the rib part of the recovery cap, improving sealing performance and reducing the negative impact. This ensures that leaks due to pressure are prevented. At this time, even if the meniscus retreats due to a reduction in the internal volume of the cap, no problem occurs because it returns to its original state by the suction operation.

Now, regarding the pump operation, when the recovery operation is started after the above-mentioned sealing cap is completed, the suction operation is started.

At this time, first, due to the rotation of the timing gear 21, the piston set cam 21f pushes the piston pressing roller 29 attached to the piston shaft 27, so the piston shaft 27
moves in the H direction as shown in Figure 9 (^). Then, the piston 28 is pressed by the piston holder 27b and
direction, and the pump chamber 42 becomes 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 holder 27b, ink will not leak through the communication hole of the foam material.

Further, the ink flow path 24e of the cylinder 24 is connected to the piston 28.
Since the piston 28 is closed, the piston 28 is in a movable state only by increasing the negative pressure in the pump chamber 42. on the other hand,
After the above-mentioned recapping, as shown in Figure 9 (^),
Since the ink flow path 24e is opened, the ink in the head 9 is sucked through the suction port 35c of the cap 35, as shown in FIG. 6(C). The sucked ink passes through an ink passage 32f formed inside the cap lever 32, passes through a communication hole in the lever seal 33, further passes through an ink passage 24e of the cylinder 24, and flows into the pump chamber 42.

When the timing gear 21 further rotates, the cap 35 is moved slightly away from the discharge port formation surface by the cap cam 21e again, and the remaining negative pressure in the pump chamber sucks the ink in the discharge port formation surface and the suction cap 35b, and these parts are Eliminate ink residue.

Next, when the timing gear 21 is rotated in the opposite direction (the direction indicated by the arrow ■ in FIG. 7(D)), the piston reset cam 21g pulls the piston return roller 30, as shown in FIG. 9(B). The piston glaze 27 is moved in the direction of arrow J. At this time, the piston 28 moves after coming into contact with the piston receiver 27c of the piston shaft 27, so the piston 28
A gap Δρ is created between the end surface 28b of the piston holder 8 and the piston holder 27b.

Therefore, the waste ink sucked into the bib chamber 42 due to the daytime operation of the piston shaft 27 and the piston 28 passes through the above-mentioned gap Δ°C, passes through the groove 27f of the piston shaft,
The ink passes through the ink flow path 24c of the cylinder 24, and further passes through the waste ink pipe 24g, and is discharged near the center of the waste ink absorber 37. 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, waste ink does not flow back toward the cap.

FIG. 1θ shows the above sequence of preliminary ejection or suction recovery. However, in the diagram, blade 1
7 is ready for wiping (set state. Fig. 7 CB)
), and after wiping, the blade 17 is tilted relative to the absorber 23 (reset state, Fig. 7(A)).
), and then immediately before the set lever 20 returns to its original position, the blade 17 is brought into a set state capable of wiping.

It should be noted that the present invention is not limited to the above-mentioned configuration, and can take various configurations, so other embodiments of each part described above will be illustrated.

FIG. 11 shows another embodiment of the blade and ink carrier portion. The ink carrier main body 119 according to this example is formed of an elastic member such as rubber, and the ink carrier body 119 described above is
The ink receiver portion 119a, which performs the same function as the above, is formed by forming a large number of grooves or unevenness. Then, the surface tension holds the ink and transports it to the ink absorber 23. The main body of the ink carrier 119 also includes a blade 119b for wiping the ejection port forming surface 9a of the head 9.
are integrally formed. According to this, since the ink carrier main body 119 can be directly provided on the set lever 20, the blade lever 16 is also unnecessary, and the number of parts can be reduced and the apparatus can be configured into 100 million pieces.

In addition, when the discharge direction is downward, blade 1]9
When wiping is performed in step b, the ink on the ejection port forming surface is stopped by the grooves or unevenness, and does not flow out to other mechanical parts, thereby preventing contamination of the equipment.

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

This embodiment eliminates the need for the above-mentioned ink absorber 23 and its holding member, and can be widely disposed at the bottom of the chassis, so it is suitable for devices that preliminarily eject a large amount of ink.

FIG. 13 shows another embodiment of the piston part. In the piston 128 according to this example, the skin layer 150 is not present on its end face, and the piston holder 127 is provided with a collar 151 as shown to hold the piston 128 in a compressed state.

Such a configuration not only maintains airtightness, but also allows the piston 12B to be manufactured by cutting a long piston material, thereby reducing the cost to 100 million pieces.

FIG. 14 shows yet another embodiment of the piston section. The piston 228 according to this example is formed of a plate-like member.

Since such a piston can be easily manufactured by pressing or the like by shielding the skin layer (253) in the thickness direction, the manufacturing cost can be further reduced.

FIG. 15 shows still another embodiment of the rear portion of the cap portion 35. As shown in FIG. In this example, a rib 3Se is provided on the sealing surface 35d, and the deformation of the rib portion further ensures airtightness.

FIG. 16 shows still another embodiment of the rear portion of the cap portion 35, and this example includes a spherical seal portion 35d and a protective seal portion 35f covering it. According to this example, it is possible to prevent ink from sticking to the aforementioned spherical seal portion 35d or dirt from entering the seal portion 35d when the cap is not on, thereby preventing the sealing performance from deteriorating.

FIG. 17 shows still another embodiment of the rear portion of the cap portion 35. As shown in FIG. In this example, a spherical seal 350 is provided at the connection between the cap lever 332 that holds the cap 35 and the pump cylinder 24, and all seals in the ink flow path are pressed with the same spring force. It is designed so that it can be sealed. 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 serving as the conveying 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 can be reduced, and the load on the paper feed motor 39 can be reduced.

FIG. 19 shows still another embodiment of the waste ink absorption section.

A hollow shaft 2 is provided at the center of the waste ink absorber 237 according to this example.
61 passes through the hollow shaft 261, and openings 262 and 263 are provided at the ends and center of the hollow shaft 261, respectively. Further, 264 is a lid.

In this example, the waste ink passes through the hollow shaft 261, and the hollow @261 can also function as a guide shaft for the paper feed roller 38. In this case, there is no sliding part on the paper feed roller, and the load on the paper feed motor is further reduced.

In this example, the main ink discharge section 263 is provided in the central region in the longitudinal direction of the platen roller, but a second ink discharge section is provided upstream of this discharge section 263 with respect to the ink guide member, and a third ink discharge section is provided downstream of this discharge section 263. An ink discharge section may be provided.
Further, the size of each part may be such that the former is smaller than the central part and the latter is larger.

FIG. 20 shows still another embodiment of the waste ink absorption 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. be. According to this example, it is possible to eliminate the difficulty of inserting a non-rigid member, such as a flexible tube, close to the center. At this time, half of the waste ink absorber 337 has its tube removed, but if polyester cotton or the like is used, the hole is closed because it is sufficiently compressed.

In addition to being provided inside the roller-shaped conveying means as described above, the waste ink absorbing section can be provided at an appropriate location inside the conveying means depending on the configuration of the conveying means. For example, when the conveyance means is composed of a plurality of rollers and a belt stretched between the rollers, it may be provided within 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 formed into a flat plate-like member to prevent the discharge port forming surface from coming into contact with air, which further improves the sealing effect. In addition, the ink flows out from the ejection port due to surface tension and comes in contact with the outside air around the cap, causing the ink to thicken or stick in this area.In other words, this occurs in areas other than the ejection port, so after opening the cap, Problems are less likely to occur in recording operations.

FIG. 22 shows yet another embodiment of the cap 35.

In this example, the sealing cap 235a is formed of a single-cell porous block such as urethane foam, which improves adhesion by adhering closely to the unevenness of the discharge port forming surface, and reduces the pressing force of the cap. Become.

FIG. 23 shows yet another embodiment of the cap 35. In this example, the sealing cap part 3 is made of open-cell urethane foam.
A skin layer 335b on the main body of 35a is formed on the nozzle contact surface, and cap performance is guaranteed over a long period of time due to the stability of the repulsion coefficient, which is a characteristic of open-cell urethane foam.

FIG. 24(A) shows another embodiment of the blade. In this example, as shown in FIG. 24 (phantom or (C)),
There is a step on the surface 9d, which is also effective for wiping the surface on the back side. That is, in this example, short fibers 117a made of a polymeric material are electrostatically attracted and adhered to the entire surface of the blade 117 or a part of the blade 117 that contacts the nozzle surface. Not only can it be wiped, but it can also effectively remove long items such as thread-like dust.

FIG. 25 shows yet another embodiment of the blade.

In this example, the blade 217 is shaped like a brush, and can be formed by bundling fibers 217b made of a polymeric material such as plastic. In this example, Fig. 24 (It) or (C)
The wiping effect is great even when the grooves on the discharge port forming surface with steps are deep, and the pressing force of the blade against the discharge port forming surface 9d is such that each bristles come into contact with each other. Therefore, it is sufficient even if it is small, and the durability of a surface treatment layer such as a water repellent agent that is sometimes applied to the surface where the ejection port is formed will not be impaired.

[Effects of the Invention] As is clear from the above description, according to the present invention, - Since the present invention includes an elastic porous layer, foreign matter such as dust attached to the ejection port surface of the recording head is removed from the piston shaft surface. Or, even if the foreign matter enters the sealing part on the inner surface of the cylinder, the piston itself partially deforms and absorbs the voids created by the presence of the foreign matter, maintaining the sealing effect.As a result, there is little deterioration in sealing performance and it is extremely stable. suction operation is possible.

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

In general, by using an elastic porous body for the piston body, its operating force becomes uniform, and stable suction operation becomes possible.

In addition, a path for discharging waste ink to the waste ink tank is formed in the suction pump in conjunction with the suction operation for ejection recovery.

In addition, in a 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, thereby eliminating the space occupied by the waste ink tube, and making the apparatus compact and simple.

Furthermore, since the suction pump can be downsized, the device can also be downsized.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an embodiment of an inkjet printer according to the present invention; FIGS. 2A to 2C are partial perspective views showing an embodiment of a blade and an ink carrier section for a recording head; and FIG. 4 are an exploded perspective view and a sectional view, respectively, showing an embodiment of the suction recovery system for the recording head. FIG. 5 is a timing chart showing the operation timing of each part related to the embodiment. FIG. ) to (C) are plan views for explaining the positional relationship between the recording head and members used for these processes during preliminary ejection, capping, and suction recovery, and FIGS. 7(8) to (D) are A side view for explaining the sequential operations of the blade and the ink carrier section, FIG. 8(A)
-(C) are side views for explaining the sequential operations of the cap section, FIGS. 9(A) and (B) are side sectional views for explaining the operations of the pump section for performing suction recovery, and FIG. Figure 1O is a timing chart explaining the sequence during preliminary ejection or suction recovery processing according to this example (some other examples), and Figures 11 and 12 are two other examples of the blade and ink carrier section. Perspective views shown in Figure 13 and Figure 1.
Figure 4 is a sectional view showing two other embodiments of the piston arranged in the pump section, Figures 15 to 17 are explanatory diagrams showing three other embodiments of the connection part in the suction recovery system behind the cap, Figures 18 to 20 are perspective views showing three other embodiments of the waste ink absorbing section disposed within the paper feed roller, and Figures 21 to 23 are perspective views showing other three embodiments of the sealing cap section of the cap. Perspective views shown in Figures 24 (A), (B), (C) and 25.
The figure is a perspective view for explaining two other embodiments of the blade.
FIG. 26(A) is an external perspective view showing an ink suction configuration in a conventional ejection recovery system, and FIG. 26(6) is a perspective view showing details of a piston in the suction pump shown in FIG. 26(A). . l...Chassis, 2...Lead screw 2a...Lead groove, 3...Lead boot 9. 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 portion, 9C... Discharge port, 9d... Discharge port forming surface, 11... Carrier motor, l3... Timing belt, 15... Set shaft, 16 ...Blade lever 17.119b, 117,217...Blade, 19
j19, 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 suppression roller, 32...Cap lever 34...Cap holder, 35...Cap, 35a, 135a, 235a, 335a-sealing cap, 35b... Suction cap, 37.337...Waste ink absorber section, 40...Recording medium, 41...Home position detector, 42...Pump chamber. 20e -B' Whistle 6 M Figure 8 Figure 12 Figure 14 Figure 76 Figure 17 Figure 20 @ Figure 19 Figure 21 Figure 22 Figure 23 (A) Figure 24 CB) Figure 25

Claims (1)

[Scope of Claims] 1) An inkjet recording apparatus comprising a suction pump that improves the ink ejection condition by suctioning ink from the ejection port of a print head that performs printing by ejecting ink from the ejection port, wherein the suction pump An inkjet recording device characterized in that the pump has a cylinder and a piston that reciprocates within the cylinder, and has an elastic porous layer as an inner layer when viewed from a sliding portion of the piston with the cylinder. 2) The inkjet recording apparatus according to claim 1, wherein a solid layer of the elastic porous material used to form an inner layer of the piston is disposed at a sliding portion of the piston with respect to the cylinder. . 3) The inkjet recording apparatus according to claim 1, wherein the continuous fine porous body forming the piston body is continuously foamed urethane foam. 4) The piston shaft for reciprocating the piston has a collar portion disposed on both sides of the piston with a distance exceeding the axial length of the piston to press the piston during the reciprocating movement. 2. The inkjet recording apparatus according to claim 1, wherein an ink flow path is formed on a shaft between the flange portions. 5) In an inkjet recording apparatus equipped with a suction pump that suctions ink from the ejection port of a print head that performs printing by ejecting ink from the ejection port to improve the ink ejection state, the suction pump includes a cylinder and a cylinder. a piston that reciprocates within the cylinder, and has a layer of an elastic porous material as an inner layer when viewed from the sliding portion of the piston with the cylinder, and the piston has a solid layer on the ink suction side. An inkjet recording apparatus characterized by forming negative pressure and forming an ink recovery path.