JPH02102065A - inkjet device - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an inkjet device equipped with a recovery system for maintaining the stability of ink ejection from the ejection ports of an inkjet head.

[Prior Art] An inkjet recording device is a recording device that uses ink as a printing medium, and ejects ink from nozzles of a head onto printing paper. However, if the state of not printing continues, the ink in the nozzle will often become stuck, making it impossible to eject ink from the nozzle even if a print signal is received. Therefore, in such a case, a recovery system exists to eliminate the ink sticking in the nozzle, and there are two types of recovery systems: a pressure type and a suction type. The pressure type pressurizes a part of the ink supply system to the head to forcibly push ink out of the nozzles of the head, eliminating clogging caused by ink sticking. On the other hand, the suction type sucks out the ink from the front of the head where the nozzles are located, and a pump is used as the means for this purpose. The prior art describes this type of suction. In this suction type, the front of the head is sealed with an elastic member such as rubber (this is called a cat), and a tube is attached to this.
Connect to pump. The recovery capacity of the recovery system is determined by the suction capacity of the pump at this time, that is, how large a negative pressure is generated. The details of the pump drive will be explained below.

FIG. 12 is a sectional view of the drive section of the pump 101. The pump 101 consists of a cylinder 102 and a piston 103, and the cylinder 102 consists of two parts, an upper cylinder 102a and a lower cylinder 102, so that an O-ring 104 can be installed.
b are integrated by welding. Furthermore, the cylinder 102
is fixed to the recovery system base 107 with screws 105 and a seal 106 . Here, the piston 103 consists of a shaft in the center and a part where a piston ring 108 is installed, and a parallel pin 109 is press-fitted into the upper part of the shaft, while a groove part in which an O-ring 110 fits is provided in the lower part of the shaft. ,
An O-ring 110 is installed here, and spaces G and H are created in the cylinder 102. The piston 103 is the pump cam 1
11 rotates, the parallel bottle 109 slides in the pump cam groove 111a, thereby moving in the vertical direction (■ direction).

The piston ring 108 and the cylinder 102 slide with each other through silicone grease, but since ink is also attached to the wall of the cylinder 102, if left for a long time, the piston ring 108 will stick to the cylinder 102. do,
Piston 103 may become unable to move.

This adhesion force is about 10 kg. Therefore, in order to prevent this, it is necessary to use a positive cam that moves the piston 103 reliably.

Now, when the piston 103 moves downward, the space G
increases, and space H decreases. Since the pressure in this space-time G becomes smaller than atmospheric pressure and becomes negative pressure, the cylinder 102
Ink flows into the cylinder 102 from the ink population 102C, and the ink present in the space H is discharged from the waste ink outlet 107a because the pressure in the space H becomes greater than atmospheric pressure. At this time, the valve 112 attached to the piston 103 is in a closed state. On the other hand, when the piston 103 moves upward, the ink population 102C is in a position where it is immediately closed by the piston ring 108, so the pressure in the space G increases, the pressure in the space H decreases compared to the space G, and the waste ink Since it is open to atmospheric pressure through the outlet, the space G
The pressure of is equal to atmospheric pressure. Therefore, the valve 112 is in an open state, and ink flows from the space G to the space H. Here, the suction capacity of the pump 101 is determined by how much the negative pressure in the space G is increased.

Fig. 13 is a diagram when the piston 103 reaches the top dead center, and if the distance xO is maintained from the top of the cylinder 102, the first
Figure 4 shows cylinder 1 when piston 103 reaches top dead center.
02, but the piston 10
When 3 moves downward with the same stroke, after the movement, the space G
The pressure in FIG. 14 becomes significantly smaller, and the suction capacity of the pump becomes extremely large. Therefore, the key point is how to approach the form shown in FIG. 14.

[Problems to be Solved by the Invention] In the pump drive shown in the conventional example, it was impossible to make the piston 103 touch the top of the cylinder 102 when it reached the top dead center due to variations in the dimensions of the parts. . In other words, the top dead center of the piston 103 may be further upward than the top of the cylinder 102, and in this case, the pump cannot be driven. Therefore, due to variations in the dimensions of parts between the top dead center of the piston 103 and the upper part of the cylinder 102, even in the worst case, the top dead center of the piston 103 is the cylinder 1.
Piston 103 so as not to exceed the top of 02.
A distance of Xo must be maintained between the top dead center of the cylinder 102 and the top of the cylinder 102. This has caused a problem in that the suction capacity of the pump is significantly reduced.

[Means for Solving the Problems] An inkjet device of the present invention that solves these problems includes a spring for urging the piston so that the top dead center of the piston comes into contact with the end of the cylinder. , a pump means used to recover the inkjet head, and a cam connected to the piston to drive the piston.

[Operation] Conventionally, due to the structure, it was necessary to provide a distance between the top dead center of the piston and the top of the cylinder, but in the present invention, a spring is embedded in the pump, and preferably a distance is provided between the top dead center of the piston and the top of the cylinder. By increasing the width of the groove and creating play so that the piston always comes into contact with the top of the cylinder when it reaches top dead center, the negative pressure of the pump can be significantly increased. This is an attempt to downsize the recording device.

That is, according to the present invention, when the spring is embedded in the pump and the piston reaches the top dead center, the upper part of the cylinder and the upper part of the piston come into contact with each other, and the upper part of the cylinder and the piston at this time contact each other. By minimizing the volume caused by the piston and by increasing the width of the groove in the piston cam, the negative pressure in the pump increases significantly even when the piston is moved by the positive cam, which also prevents pump failure due to sticking of the cylinder and piston. Moreover, since the suction capacity of the pump is significantly improved, the pump can be downsized, and an inkjet recording device equipped with a highly reliable and compact recovery system can be realized.

[Examples of Embodiments] Examples of embodiments of the present invention will be specifically described below with reference to the drawings.

FIG. 1 is a perspective view showing a recovery system of an inkjet recording apparatus. Reference numeral 1 denotes an inkjet head (hereinafter referred to as head), which uses, for example, thermal energy to eject ink as droplets to create an image. Reference numeral 2 denotes a carriage to which a head is fixed, and the carriage 2 prints on printing paper 4 while moving left and right on a carriage shaft 3 by a carriage motor (not shown) and a timing belt integrated with 2. Reference numeral 5 denotes a pinch roller stay that rotates around an axis (not shown) according to the thickness of the printing paper 4, and a part of the carriage 2 slides on this pinch roller stay 5 under the pressure of the carriage 2's own weight. As a result, the gap between the printing surface of the printing paper 4 and the head 1 is always kept constant regardless of the thickness of the printing paper 4, and high printing quality is maintained. This head 1
A recovery system exists to stabilize the ejection of ink droplets from the nozzles.

When the head 1 is not printing for a certain period of time, the nozzle surface of the head 1 is sealed with a cap 6 to prevent non-ejection of ink due to ink sticking to the nozzle. This cap 6
As shown in FIG. 2, the sealing mechanism is such that the cap 6 is held by a cap holder 7, and the cap holder 7 is held by a holder 8. Here, a cap spring 9 is interposed between the cap holder 7 and the holder 8 so as to press the head 1 into close contact with an appropriate force.
a is inserted into the hole 8a of the holder 8 and secured with a snap.

The dowels 7b on both sides of the cap holder 7 enter the U grooves 8b of the holder 8, and the cap holder 7 integrated with the cap 6 swings about the U grooves 8b in accordance with the surface of the head 1 using these as fulcrums. There are two dowels 8c on the top and bottom of the holder 8, and these dowels 8C enter the U groove 9a of the slider 9, thereby completing the cap unit. Cap holder 7 and holder 8 are indicated by arrow A
The holder 8 and slider 9 can be moved in the direction of arrow B.
It is possible to move in the direction. Therefore, the cap 6 is attached to the slider 9,
A cap holder 7 and a holder 8 are held, and the dowel 2a of the carriage 2 enters the hole 9b of the arm portion of the slider 9 as the carriage 2 moves from the printing section toward the recovery system along the carriage shaft 3, and the slider 9 moves along the slide shaft 10 to the left in FIG. 1 together with the carriage 2. At this time, the roller 1 inserted into the dowel part 8c of the holder 8
1 slides and rotates around the slot 12a of the flat cam 12, the holder 8 protrudes toward the head 1, and at the same time the slider 9 moves leftward. As a result, the cap 6 is pressed against the face surface of the head 1. The pressure contact force at this time is 30
It is about 0 to 500 g.

At this time, as shown in FIG.
are pressed together with a force of about 100 g by a mechanism to be described later. At this time, the atmosphere communication hole 6b is closed, and since the large recovery cap tube 14, which will be described later, is closed by means described below, the large recovery hole 6c is also closed. On the other hand, the waste ink cap tube 15 is connected to the pump 16 in FIG.
6, when the piston 17 moves toward the back in the C direction, negative pressure is generated in the pump 16, and negative pressure is also generated in the cap 6 that is in pressure contact with the head 1, so ink is forcibly sucked from the nozzle of the head 1. Therefore, dust, a fixed layer of ink, etc. on the nozzle are sucked into the cap 6, and the phenomenon of the head 1 not ejecting is eliminated. When the piston 17, which has reached the bottom dead center, moves toward the head side in the D direction due to the cam movement described later, the inside of the pump 16 is pressurized, and the ink sucked from the cap 6 passes through the waste ink tube 18 as waste ink. Ink cartridge 19 from waste ink intake port 19a
is discharged into the waste ink reservoir. When waste ink is discharged, there is no pressure change to the cap 6 due to the structure of the pump. In this state, the ink sucked from the nozzle of the head 1 is still in the cap 6 and the waste ink cap tube 15.
Therefore, if the surface tension of the ink is greater than the ink ejection force, ink may not be ejected or the ink may not be ejected.
Furthermore, when a blade 24 (described later) comes into contact with the ink, the printing paper 4 is smeared due to ink scattering, resulting in a significant deterioration in printing quality.

In order to solve this problem, the next sequence is to remove the ink inside the cap 6 and the ink attached to the face of the head 1 by opening the air valve of the cap 6 while the cap 6 and the head 1 are in pressure contact. By moving the carriage 2 slightly to the right (2 mm in this embodiment) so as to release the contact between the stopper 6a and the stopper 13, and operating the pump unit in this state, the atmosphere communication hole 6b is opened as shown in FIG. Since it is L-shaped and installed on the upper side of the cap 6, air is sucked into the cap 6 through the atmosphere communication hole 6b, and the waste ink cap tube 15 is attached to the lower side from the upper side of the cap 6. Because the air flows to the ink in the cap 6 and the head 1
The ink attached to the face of the machine is removed. After that, the face surface of the head 1 is rubbed by the rubbing member 20 by means described later.
protrudes and the carriage 2 moves from left to right to rub, remove ink and stains from the face, and ensure ejection stability of the head 1. As shown in FIG. 5, this squeeze mechanism inserts a ring-shaped rubbing member 20 into an oval-shaped rubbing inserter 21, and the rubbing inserter 21 is inserted into the rubbing holder 22, and the dowel 21a of the rubbing inserter 21 is inserted into the The rubbing holder 22 is fixed to the groove 22a by a bolt, and is installed by inserting the claw part 22b of the dowel of the rubbing holder into the hole 24a of the rubbing slider 24 via the rubbing spring 23, and the rubbing member 20 is movable in the D direction. becomes.

The protrusion of the rubbing slider 24 is performed by a cam described later, and the part 24b of the rubbing slider 24 returns to its original position.
It utilizes the restoring force caused by the elastic deformation of Here, the cam comes into contact with the dowel portion 24c of the rubbing slider, thereby causing the rubbing member 2o to protrude. This rubbing member 2o is made of an ether-based polyurethane continuous pore material. Furthermore, in order to ensure the ejection stability of the head 1 before the rubbing by the rubbing member 2o, a blade 25 existing between the rubbing member 20 and the cap 6 is used to prevent paper dust or other dust from adhering to the nozzle during printing. , and wipe them off with a blade 25 to remove them. This blade 25 is made of transparent silicone rubber with a wall thickness of about 0.3 to 0.5 mm. This blade 25 is attached to a part of the recovery system base 27 by a blade holder 26 and always protrudes, so that whenever the head moves in front of it, wiping is always performed with the blade 25. During printing, the slider 9 is returned to the right by the slide spring 28 as shown in FIG. The cap 6 is located at a position determined by the position in which it abuts. On the other hand, during printing, in order to prevent the nozzles of the head 1 that are not in use from sticking, the head 1 returns to the position held by the cap 6 and performs empty ejection from all nozzles at certain predetermined intervals.
Wiping is performed by the blade 25 during the reciprocation of the head 1 at this time. Naturally, wiping with a blade is also performed when a recovery operation is performed. When empty discharge is performed here, the dowel 8C of the holder 8 is connected to the cam surface 12 of the flat cam 12.
Since it is in contact with the lower surface of a, cap 6 and head 1
The ejected ink is absorbed and held by the polymer absorber 29 in the cap 6, and is absorbed toward the pump 16 when the pump 16 is operated.

Also, the dowel portion 2a of the catridge 2 is inserted into the hole 9 of the arm portion of the slider 9.
When the carriage 2 moves to the left, the dowel 8C of the holder 8 climbs the slope of the cam surface 12a of the flat cam 12, and the cap 6 and head 1 are brought into pressure contact with each other. Next, the cam operation will be described. When the paper feed motor of the recording apparatus main body (not shown) rotates in the normal direction, the paper feed motor has the function of feeding the paper, but when the paper feed motor rotates in the reverse direction, the paper feed roller shaft 30 and the recovery system drive gear 31 are integrated by the clutch spring 32. The cam gear 34 rotates via the idle gear 33, and the cam shaft 35 integrated with the cam gear 34 rotates the rubbing cam 36, the pump cam 37° 38, and the home position cam 39. Here, the piston 17 of the pump 16 is provided on the surface facing the pump cams 37 and 38.
A groove 37a is provided so that both ends of the parallel pin 40 integrally connected to the pump cams 37 and 38 are positive cams, and the rotation of the pump cams 37 and 38 causes the parallel pin 40 to slide. The piston 17 is actuated in the C direction. When the power is turned on, the recovery system drive gear 31 rotates, the home position cam 39 also rotates, the home position switch 50 is turned on, and the cam group is initialized.

The recovery operation described above is called a small recovery and is performed when the non-ejection can be easily resolved, but when the non-ejection cannot be easily resolved due to sticking of the nozzle of the head 1 or the like, a large recovery is performed.

The position of the head 1 during the large recovery is a position where the air valve 6a of the cap 6 comes into contact with the stopper 13 and has moved 2 mm to the left compared to the position during the small recovery while maintaining the air communication hole closed. Here, the mechanism of the large recovery operation will be explained based on FIG. A stopper 13 can be smoothly slid in the direction of movement of the carriage 2 by a part 12b of the flat cam 12.
In this stopper 13, a protrusion 13a of the stopper 13 fits into a U groove 41a of the stopper lever 41. Stop lever 41
The fulcrum portion 41b fits into the dowel portion 12c of the flat cam 12. Furthermore, a large recovery valve 42 is installed in a portion 12d of the flat cam 12, and the large recovery valve 42 has a hole 42a and a hole 42b.

There is a thin hole 42c, and inside there is a hole 42a and a thin hole 42.
b, 42c are in communication. This communication 4
2b, 42c is opened and closed by the valve piston 43. A large recovery spring 44 is interposed between the valve piston 43 and the hole 41c of the stopper lever 41, and the valve piston 43 is moved by the U? Enter M141d. A stopper spring 45 is inserted into the fulcrum part of the stopper lever 41, one end 45a of the stopper spring 45 abuts on a hook part (not shown) of the flat cam 12, and the other end 45b contacts a part 41e of the stopper lever 41.
is in contact with.

Therefore, a restoring force can be obtained when the stopper 13 is moved leftward. Based on such a mechanism, when the pump is operated with a small recovery, the valve piston 43 and the hole 41c of the stopper lever 41 are closed.
The valve piston 43 is in pressure contact with the large recovery valve 42 by the large recovery spring 44, and the thin holes 42b and 42c of the large rotation double valve 42 are not in communication with each other. When moving 2 mm to the left from this state for a large recovery operation, the inner wall of the hole 41c of the stopper lever 41 comes into contact with the valve piston 43, and the valve piston 43 moves in the direction of coming out of the large recovery valve 42, so the thin hole 42b , 42c communicate with each other.

Therefore, ink can be supplied from the ink cartridge to the upper part of the cap 6 using the tube described later.

Here, the arrangement of the tubes will be explained based on FIG.

An ink outlet 19b is provided at the top of the ink cartridge 19.
This is provided with a three-way joint 46, and an ink supply tube 47 is connected from one opening of the joint to a sub-tank (not shown) of the carriage 2, and the sub-tank is connected to the head 1 by a tube (not shown). The sub tank tube 48 connects to pump 1 from a part of the sub tank.
6 is connected to the ink suction port 16b. Further, as described above, the narrow hole 42C of the large recovery valve 42 and the cap 6 are connected by the large recovery cap tube 14, and the narrow hole 42b of the large recovery valve 42 is connected to the ink outlet of the ink cartridge 19 via the three-way joint 46. It is connected to the outlet 19b by a large recovery tube 49. Waste ink from the pump 16 is collected into the ink cartridge 19 via a waste ink tube 18 that connects a part 27a of the recovery system base 27 and the waste ink intake port 19 of the ink cartridge 19. The waste ink sucked from the lower side of the cap 6 by the pump 16 is sucked into the ink suction port 16a of the pump 16 by the waste ink cap tube 15. The above is an explanation of the arrangement of the tubes.

Therefore, during large recovery, the cap 6 and the face of the head 1 are in pressure contact as in the case of small recovery, so when the piston 17 of the pump 16 moves in the direction C, ink flows into the cap 6 from the large recovery hole 6C. At the same time, ink also flows into the cap 6 from the nozzle of the head 1, and then the pump 1
6, the ink is discharged toward the waste ink reservoir. After performing this pumping operation four times, the ink is collected in the space formed by the cap 6 and the face of the head 1, and the head 1 is moved 21nffl to the right to open the flow path of the large recovery valve 42 with the stopper spring of the stopper lever 41. 45 to return the valve piston 43 to its original position, the narrow hole 42 of the large recovery valve 42 is removed.
b and 42c are closed and kept in this state for about 1 minute to soak the fixed ink and soften it, and then operate the pump to discharge the ink from the space formed by the cap 6 and the face of the head 1. At the same time, ink is sucked and discharged from the nozzles of head 1, and then head 1 is moved further to the right.
By moving the air valve 6 of the cap 6 by
By opening the atmosphere communication hole 6b of a and operating the pump, air is sucked from the atmosphere communication hole 6b, and the cap 6
The ink on the face surface of the head 1 and in the cap 6 is removed in order to flow into the waste ink discharge port 6d. The above is a major recovery operation.

In addition, this recovery system unit is attached to the dowel 27 of the recovery system base 27.
It is easily secured to the main body by b and 27c. Further, the flat cam 12 and the recovery system base 27 are held together by mutual claws.

Figure 7 is a cam diagram showing the operation of the head 1 when the power is 08 and a small recovery. Figure 8 is a diagram showing the operation of the head 1 when the power is 08 and a small recovery. The X-axis is the carriage 2 drive on which the head 1 is mounted. The y-axis indicates the moving direction and distance of the head 1 with the number of pulse motor steps. Similarly, FIG. 9 is a cam diagram during a large recovery, and FIG. 10 is a diagram showing the operation of the head 1 during a large recovery.

These diagrams will be explained below.

First, at power supply 08, the cam group rotates to initialize the recovery system, and the home position cam 39 rotates until the home position switch 41 is turned on.After the home position switch 41 is turned on, it rotates another 10', and the state becomes @. . At this time, the piston 17 of the pump 16 has reached the top dead center, the rubbing member 20 is in a standby state, and the head 1 is in an arbitrary position within its movable range.The cap 6 and the face of the head 1 are not pressed against each other, and naturally the air valve 6a It will be released. Thereafter, the cam group rotates to an absolute angle of 83 degrees, and then the head 1 moves to a position where the air valve 6a is closed. The rotation angle of the cam group will be described below in terms of absolute angles, and the position of head 1 will be referred to as the origin. In this state (■), the cam group rotates, and the suction of the pump 16 starts from 150°, reaches the bottom dead center at 230°, and stops the rotation of the cam group for 0.8 seconds at 245° to suck in enough ink. Then, move the head 1 to the right 21 and open the air valve 6a. After that, the cam group rotates and after reaching 260°, the piston 17 rises and reaches the top dead center at 340°.
While keeping head 1 in this state, move the cam group at a constant speed (2 x 360° + 83°), then move head 1 2m to the left.
Move mfJ and enter state ■. In addition, the cap diagram (2x3
Between 60°+to'') and (2×360°+83°), a two-dot chain line appears when the power is turned on. In state (2), the head 1 operates and prints in response to data transfer, and after printing is completed, the state returns to (2).

Next, during a small recovery, state ■ is the same as state ■, so the explanation will start from state ■. The diagram from state ■ is (2X36
0" + 10") is exactly the same as the diagram when the power is turned on, and when it reaches (2x360° + 10"), head 1 moves 5 mm to the right, and the cam group rotates from 2 The rubbing member begins to protrude (2 x 360 @
+48°), the protruding state continues, and (2X360'
+57°), the cam group stops rotating and the head 1 further moves 9.5 mm to the right. At this time, the face surface of the head 1 is rubbed by the rubbing member 20 and cleaned. After that, the cam group rotates (2X360°+66°
), the rubbing member 20 begins to return to the standby state (2x
360°+78°), the rubbing member 20 returns to the standby state (
2x360°+83°), the cam group stops, the head 1 moves 16.5 mm to the left, the cap 6 and the face of the head 1 are brought into pressure contact, the air valve 6a is closed, and the cap 6 is completely sealed. state and reached state ゛■,
Waiting for data transfer.

Next, I will explain the diagram of the Great Recovery. Waiting for data transfer is performed in the above-mentioned state (3), but in the large recovery operation, the head 1 moves 2+nm'8 to the left from this state, and the movement of the carriage 2 abuts the stopper 13 to open the flow path of the large recovery valve 42. shall be. After that, the cam group rotates once, and from 150°, the pump 16
The piston 17 begins to move down and reaches the bottom dead center at 230'' and reaches 245°. At state (2), the rotation of the cam group stops for 0.8 seconds, and the negative pressure generated in the pump 16 causes the nozzle of the head 1 to and a large recovery hole 6C provided on the upper side of the cap 6.
After more ink is sucked, the rotation of the cam group resumes.26
The piston 17 rises from 0° and rotates until it reaches the top dead center at 340° (360'+83'), reaching state (3). Repeat these Stage I three times, then (3
x360°+245°), the cam group pauses for 0.8 seconds, then rotates at a constant speed until (4 x 360°+10°), and in state [phase] head 1 moves 2mmfg to the right. The valve piston 43 returns to its original position, and the large recovery valve 48 is closed. Hold this state for 1 minute to soften the fixed ink layer of the nozzle of head 1, and then the cam group (4X
360° +83°) and reaches state 0. The period from this state ■ to state 0 is called stage 1 ■. The operation after this is exactly the same as the small recovery operation. In other words, the large recovery operation can be said to be an operation in which stage I is performed three times, stage 11 is performed once, and then a small recovery operation is performed.

The above is the explanation of the cam diagram and the head operation diagram.

Next, the present invention will be explained in detail.

FIG. 11 is a sectional view of the pump of the present invention, and the difference from the conventional example is that a compression spring 51 is attached to the lower part 17a of the shaft of the piston 17.
are installed, and the groove cam portions 37a of the piston cams 37, 38.

As for the shape of 38a, the two-dot chain line is the conventional shape, and the solid line is the shape of the present invention.In short, when pushing down the piston 17, it has the same shape as the conventional grooved cam part, but when pushing up the piston 17, it depends on the force of the compression spring 51. The grooved cam portion is shaped so that it does not come into contact with the parallel bottle 40 so that the piston 17 is pushed upward, and naturally the top dead center of the piston 17 is determined by the force of the compression spring 51 hitting the upper surface of the cylinder.

In the above conventional example, a compression spring is embedded in the lower part 17a of the piston 17, but the camshaft 35 is not limited to this method.
Naturally, a tension spring tensioned between the piston 17 and the piston 17 has the same effect. Note that although the explanatory drawing shows the pump installed vertically, in the embodiment it is installed horizontally.

[Effects of the Invention] As detailed above, when the spring is embedded in the pump and the piston reaches the top dead center, the top of the cylinder and the top of the piston come into contact, and the top of the cylinder at this time and the top of the piston come into contact with each other. By minimizing the volume formed by the piston and by increasing the width of the piston cam groove, the negative pressure of the pump increases significantly even when the piston is moved by the positive cam, and the cylinder and piston This solves the problem of pump failures caused by the sticking of particles, and also significantly improves the suction capacity of the pump, making it possible to downsize the pump and create a highly reliable inkjet recording device equipped with a compact recovery system.

[Brief explanation of drawings]

Fig. 1 is an overall perspective view using the pump of the present invention, Fig. 2 is a perspective view of the structure of the cap unit, Fig. 3 is a sectional view showing the atmospheric communication hole and large recovery hole of the cap, and Fig. 4 is the recovery system. Figure 5 is a perspective view of the structure of the rubbing unit. Figure 6 is a perspective view of the flat cam unit. Figure 7 is a cam diagram when the power is turned on and a small recovery is made. Fig. 8 is a running diagram of the carriage unit in Fig. 7, Fig. 9 is a cam diagram at the time of large recovery, Fig. 10 is a running diagram of the carriage unit in Fig. 9, and Fig. 11 is a pump of the present invention. 12 is a sectional view of a conventional pump, and FIGS. 13 and 14 are explanatory sectional views of the top dead center of the pump. 1: Inkjet head 2: Carriage 3: Carriage shaft 4: Print paper 5: Pinch roller stay 6: Cap 7: Cap holder 8: Holder 9: Cap spring 10 Slide shaft 11: Roller 12: Flat cam 13: Stopper 14: Large recovery cap tube: Waste ink cap tube: Pump: Piston: Waste ink tube: Ink cartridge: Rubbing member: Rubbing inserter: Rubbing holder: Rubbing spring: Rubbing slider: Blade: Blade holder: Recovery system base: Slide spring: Polymer Absorber: Paper feed roller shaft: Recovery system drive gear: Clutch spring: Idle gear cam gear 35: Cam shaft 36: Rubbing cam 3738: Pump cam 39: Home position cam 40: Parallel pin 41: Stopper lever 42: Large recovery valve 43: Valve piston 44: Large recovery spring 45: Stopper spring 46: Three-way joint 47: Ink supply tube 48: Sub tank tube 49: Large recovery tube 50: Home position switch 51; Compression spring 101: Pump 102 Niji cylinder 103: Piston 104: O ring 105: Screw 106: Seal 107: Recovery system base 108: Piston ring 109: Parallel bottle 110: O-ring 111; Pump cam 112: Valve zrlθ π-i Ort and 1

Claims (2)

[Claims] (1) a pump means connected to the piston, which has a spring for urging the piston so that the top dead center of the piston comes into contact with the end of the cylinder, and is used to recover the inkjet head; An inkjet device comprising: a cam for driving the piston. (2) The inkjet device according to claim 1, wherein the inkjet head uses thermal energy to eject ink as droplets to create an image.