JPH10250113A - Recovery device for inkjet printer - Google Patents

Abstract

(57) [Problem] To provide a recovery device for an ink jet printer that can change the ink suction mode while securing a constant ink suction amount according to the state of nozzles and ink passages of a recording head. I do. SOLUTION: A suction pump is driven via a cam member. In the suction operation, during normal purging, FIG.
As shown in (a), without stopping the cam member,
The second piston member is moved to be sucked at once with a large suction force. At the time of automatic maintenance, FIG.
(C) As shown in FIG.
The ink cartridge is rotated after waiting for 0 ms or 200 ms to suck with a relatively large suction force. When the ink cartridge is replaced, as shown in FIG. 8E, the ink cartridge is rotated for 10 ms at 300 ms and gradually sucked with a small suction force. .

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a recovery device for an ink jet printer.

[0002]

2. Description of the Related Art Conventionally, a recording head for ejecting ink to a recording medium to perform recording, and a suction cap which comes into contact with a nozzle surface of the recording head so as to be able to come in contact with and separate from the recording head, are used to suck ink of the recording head through the suction cap. 2. Description of the Related Art There is known an ink jet printer including a suction pump unit for performing the operation and a control unit for controlling the drive of the suction pump unit.

In such an ink jet printer,
The control means controls the suction pump means to perform a suction operation. Generally, the suction operation generates one large suction negative pressure, and sucks the ink in the recording head at a stretch through the suction cap. Has been done.

[0004]

However, in the use of such an ink-jet printer, when the ink cartridge is replaced, including when the ink cartridge is first connected to the recording head, the ink passage between the recording head and the ink cartridge is required. May be filled with air.In such a state, a large suction force is applied through the suction cap in the same manner as in the normal purge operation for recovering the ejection failure during the printing operation. If the ink of the recording head is sucked at a stretch, the ink flows rapidly from the ink cartridge toward the recording head in a state of being mixed with air, the ink foams, and the ink in the ejection channel of the recording head contains bubbles. It will be. Particularly, when a filter member is provided at a connection portion between the recording head and the ink cartridge (for example, an ink supply hole of the ink cartridge) so that dust and the like do not move with the ink toward the recording head.
The tendency is remarkable.

[0005] Therefore, there is a demand that the ink should be sucked from the recording head in such a manner as not to cause the above-mentioned bubbling when replacing the ink cartridge.

On the other hand, when the ejection of the nozzle of the recording head becomes defective due to drying of the ink, clogging of dust, or the like,
It is desirable that the ink in the recording head be sucked at a stretch with a large negative pressure. In addition, at the time of automatic suction performed automatically by the timer means built in the printer according to the length of the non-use period, a relatively small negative pressure may be used because only ink that is drying from the nozzles is removed. .

[0007] Further, since it is necessary to suck a certain amount of ink for suctioning such ink, simply reducing the ink suction force reduces the total amount of ink suction and causes the ink to reach the nozzle tip of the recording head. In some cases, ink cannot be sucked.

[0008] The present invention has been made in view of the above points, and according to the state of nozzles and ink passages of a recording head,
An object of the present invention is to provide a recovery device for an ink jet printer that can change the ink suction mode while securing a constant ink suction amount.

[0009]

According to a first aspect of the present invention, there is provided a recording head for ejecting ink onto a recording medium to perform recording, and a suction cap which comes into contact with a nozzle surface of the recording head so as to be able to come and go. It is assumed that the recovery device of the ink jet printer includes a suction pump means for sucking the ink of the recording head through a suction cap and a control means for controlling the drive of the suction pump means. A movable piston member, wherein the control means selectively brings the piston member into close contact with the nozzle surface and suctions ink from the recording head by the suction pump means. They are driven at different speeds.

Therefore, in one suction operation in which the suction cap is brought into close contact with the nozzle surface to suction ink from the print head by the suction pump means, the piston member is selectively driven at different speeds by the control means, and the print head is driven. The ink suction mode is changed according to the state of the nozzles and the ink passages. Further, since the piston member is only selectively driven at different speeds, it is possible to secure a constant amount of ink suction, and it is always possible to suction ink to the nozzle tip of the recording head. Further, it can be easily realized only by changing the control with one pump.

According to a second aspect of the present invention, in the recovery device for an ink jet printer according to the first aspect, the control means drives the piston member continuously and intermittently, or intermittently at a different cycle, so that the different speeds are obtained. Is what you get.

Therefore, different speeds for driving the piston member can be obtained by a combination of continuous driving and intermittent driving of the piston member, a combination of intermittent driving of the piston member at different periods, and all combinations thereof. .

According to a third aspect of the present invention, in the ink jet printer recovery device according to the second aspect, the piston member comprises two relatively movable piston members, and the control means controls the suction pump means. And said 2
The interval between the two piston members is changed by a constant stroke amount at a constant cycle, and finally is set as a target interval.

Therefore, the interval between the two piston members of the suction pump means is changed by a constant stroke amount at a constant cycle, and finally the target interval is maintained, and a constant ink suction amount is secured. By changing the cycle and the stroke amount, the piston member is selectively driven at different speeds, and the state of ink suction is changed according to the state of the nozzle of the recording head and the ink passage.

According to a fourth aspect of the present invention, in the ink jet printer recovery device according to any one of the first to third aspects, the control means controls the suction pump means,
At the time of automatic maintenance, the speed is made slower than at the time of purge for recovering ink ejection failure, and at the time of ink cartridge replacement, the speed is made even slower than at the time of automatic maintenance.

Therefore, at the time of automatic maintenance, a predetermined suction force is secured without foaming by lowering the speed than at the time of purge for recovering ink discharge failure, and at the time of replacing the ink cartridge, the time is longer than at the time of automatic maintenance. In this case, the above speed is further reduced to a suction force for sucking the ink, and foaming of the ink is suppressed as much as possible.

According to a fifth aspect of the present invention, there is provided the recovery device for an ink jet printer according to any one of the first to fourth aspects, further comprising a cam member associated with the piston member, and a driving means for rotating the cam member. And the control means is associated with the drive means.

Therefore, the driving means is controlled by the control means, the cam member is driven to rotate at a predetermined timing, and the piston member is selectively driven at different speeds.

According to a sixth aspect of the present invention, in the recovery device for an ink jet printer according to any one of the first to fifth aspects, the cam member changes the speed of the piston member by temporarily stopping rotation. The control means changes the time of the temporary stop.

Therefore, the speed of the piston member is changed by temporarily stopping the rotation of the cam member, and the time of the temporary stop is changed by the control means. In response to the,
The manner of ink suction is changed.

According to a seventh aspect of the present invention, in the recovery device for an ink jet printer according to any one of the fifth and sixth aspects, the cam member forms at least a part of the suction cap in addition to the one suction operation. The idle suction operation of sucking ink from the inside of the suction cap by the suction pump means away from the nozzle surface of the recording head is performed.

Therefore, in addition to the one suction operation, an idle suction operation is performed in which at least a part of the suction cap is separated from the nozzle surface of the recording head and ink is sucked from inside the suction cap by the suction pump means. The ink remaining inside is sucked and removed.

[0023]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic perspective view showing the overall configuration of the ink jet printer. In FIG. 1, an inkjet printer 1 has a rotating shaft (not shown) extending in the left-right direction.
And has a cylindrical platen roller 3 rotatably supported on the frame 2 by the roller. The platen roller 3 is provided with a printing paper 4 supplied from a paper cassette or a manual paper feeding unit.
The recording medium is conveyed while facing the recording head 5, and constitutes a part of a so-called paper feed mechanism LM. The recording head 5 is of an ink jet type having a nozzle for ejecting ink droplets on the printing paper 4 and performing a recording operation on the printing paper 4, and a paper feeding mechanism LM drives the paper feeding mechanism LM. An LF motor 14 (see FIG. 5) as a paper feed motor for transporting the printing paper 4 is provided.

The printing paper 4 is supplied in the direction of arrow A from a paper supply port (not shown) behind the frame 2, is fed in the direction of arrow B by the rotation of the platen roller 3, and is discharged from the paper discharge port (not shown). ) Is discharged in the direction of arrow C. A carriage 6 is provided in front of the platen roller 3 so as to be movable in the direction of arrow D along the axis of the platen roller 3.

The carriage 6 has a recording head 5 and an ink cartridge 7 containing ink supplied to the recording head 5 detachably mounted thereon. In this example, the recording head 5 and the ink cartridge 7 each having a head portion for four colors of yellow, black, cyan, and magenta are mounted.

As shown in detail in FIG. 2, when the ink cartridge 7 is mounted on the cartridge mounting portion 6a of the carriage 6, the recording head supported by the head supporting member 16 via the manifold member 15 5. The manifold member 15
The rear end of the cartridge penetrates the vertical wall portion 6b of the cartridge mounting portion 6a and is connected to the ink cartridge 7 via the joint member 17. In the connection part, an adapter 18 is provided in the ink supply hole 7a of the ink cartridge 7, and a net-like filter member 19 is provided on the recording head 5 side so that dust and the like do not move together with the ink.

A carriage shaft 8 is provided in parallel with the axis of the platen roller 3, and a carriage 6 is slidably fitted on the carriage shaft 8. The engaging portion 6c of the carriage 6 is guided by a guide rail 9 extending parallel to the carriage shaft 8.
Thereby, the recording head 5 mounted on the carriage 6
Is reciprocally movable by sliding along the axis of the platen roller 3. The carriage 6 is fixed to a part of a timing belt 11, and the timing belt 11 is wound around timing pulleys 12, 13 to constitute a carriage mechanism CM. Motor). Therefore, when the CR motor 10 is rotationally driven, the carriage 6 reciprocates in a recording area where recording is performed on printing paper via the carriage mechanism CM. In addition, the carriage area CM and the CR motor 10 allow the recording area to be
Moving means for moving between a recovery area where a recovery operation is performed by a suction cap 41, a suction pump 42, and a wiper member 32, which will be described later, is configured. As the CR motor 10, a step motor or a DC motor is used. Although not specifically shown, the carriage 6 is provided with a cartridge replacement detection switch 21 for detecting replacement of the ink cartridge 7 (see FIG. 5).

On the right side of the recording area corresponding to the platen roller 3, there is formed a recovery area in which a purge mechanism RM for recovering from non-ejection or ejection failure of the recording head 5 is provided. Such a purge mechanism RM
Is provided by the ink jet recording head 5
The reason is that a discharge failure occurs due to a cause such as generation of bubbles inside the ink or drying of the ink during use, and this is to recover the discharge state to a favorable discharge state.

The purge mechanism RM is movable between a protruding position protruding into the moving path of the recording head 5 and a standby position retreating from the moving path of the recording head 5, and the nozzle surface of the recording head 5 at the protruding position. When the suction cap 41 is in close contact with the nozzle surface of the recording head 5 at the protruding position, the ink in the recording head 5 is suctioned and removed through the suction cap 41. Suction means 3 having suction pump 42
1 is provided.

A wiper member 32 adjacent to the suction means 31 and movable relative to the recording head 5 so as to wipe the nozzle surface of the recording head 5 on the recording area side when recording is not performed on the opposite side. A storage cap device 33 is provided to cover the nozzle surface of the recording head 5 to prevent ink evaporation and prevent the nozzle surface from drying.

The wiper member 32, the suction cap 41, and the suction pump 42 are associated with a rotationally driven cam member 43. The advance and retreat of the wiper member 32, the advance and retreat of the suction cap 41, and the operation of the suction pump 42 are as follows. It is configured to be controlled by the rotation of the common cam member 43.

Further, as shown in FIG. 3, the cam member 43 has a driving gear 46 provided integrally, and is driven to rotate by a driving means such as a motor. For example, the drive gear 46 is configured to be removably meshed with a drive gear (not shown) that is rotationally driven by the LF motor 14 of the paper feed mechanism LM. Are driven in forward rotation. The rear end (cam follower) of the wiper holder 34 that supports the wiper member 32 is movably engaged with the first cam groove 43a of the cam member 43, whereby the wiper member 32 moves the recording head 5 The recording head can reciprocate in a direction orthogonal to the moving path of the recording head 5 between a protruding position protruding into the path and a standby position retracted from the moving path of the recording head 5. No. 5 is controlled to be wiped.

The suction cap 41 is supported by a cap holder 44, and the rear end (cam follower) of the cap holder 44 has a second surface of the cam member 43 on the same plane as the first cam groove 43a. Movably engaged with the cam groove 43b.

The suction pump 42 includes a frame member 51
The first and second piston members 53 and 54 are independently and movably fitted in a cylindrical pump housing 52 attached and fixed to the pump housing 52. In the pump housing 52, a suction port 52a and a discharge port 52b are provided at regular intervals in the axial direction, and the suction port 52a is connected to a suction cap 41 via a suction pipe 55.
2b is linked to the waste ink tank 58 in which the adsorbent 57 is stored (see FIG. 1). One end side of the pump housing 52 is an atmosphere opening portion 52c opened to the atmosphere, and a first piston member 53 is disposed on the side of the atmosphere opening portion 52c.

First and second piston members 53, 54
Are connected to one ends of the first and second drive shaft members 61 and 62, respectively, and are driven by the drive shaft members 61 and 62, so that the pump chamber 52 is formed between the piston members 53 and 54 in the pump housing 52. Is formed.

The first drive shaft member 61 is slidably fitted in the second drive shaft member 62, and each of the drive shaft members 6
The other end portions of the first and second cam members 43 and 43 are opposite to the third and fourth cam grooves 43c and 43c of the cam member 43 on the side opposite to the cam grooves 43a and 43b.
43d so as to be movable.

Accordingly, by rotating the cam member 43 at a predetermined timing, capping of the suction cap 41, suction of ink by the suction pump 42, and wiping of the nozzle surface of the recording head 5 by the wiper member 32 are sequentially performed. Then, the ink sucked by the suction pump 42 is discharged to the waste ink tank 58 via the suction pump 42 and is adsorbed by the adsorbent 57 in the waste ink tank 58.

The storage cap device 33 has a storage cap 71 as shown in FIG.
Is supported by a guide rod member 73 extending parallel to the moving direction of the carriage 6 so as to be able to slide and rotate. The casing 72 engages with the carriage 6 when the carriage 6 moves to the outside of the recording area, and has an engaging projection 72a for slidingly moving integrally with the carriage 6 protruding forward. ing. Then, when the carriage 6 moves from the recording area to the recovery area, the carriage 6 engages with the engaging projection 72a of the casing 72, so that the storage cap 71 slides following the movement of the carriage 6 (FIG. 1). At right). At the time of this sliding movement, the storage cap 71 rotates around the guide rod 73 by the action of the not-shown inclined cam means, and as a result, the storage cap 71 rotates in a direction approaching the recording head 5, and the storage cap 71 Capping is performed by contacting the nozzle surface of the nozzle. Thereafter, when the carriage 6 moves in the recording area direction again, the storage cap 71 moves away from the recording head 5 while moving to the recording area side, and returns to the initial state when the carriage 5 comes out of the recovery area.

Next, the control section of the ink jet printer 1 according to the embodiment will be described with reference to the block diagram of FIG. This control unit is a well-known arithmetic processing unit C
The PU 100 is mainly configured. The CPU 100 is connected to a host computer 102 such as a personal computer via an interface 101, and the host computer 110
2, and various printings are executed in accordance with the instructions.

As a typical functional configuration of the host computer 102, there is a window system. Various applications (A) on this window system
(B)... (N) are provided, and a font driver, a CRT driver, a keyboard driver, a mouse driver, a printer driver, and the like are incorporated. When printing is performed using the inkjet printer 1 during execution of various applications, the printer driver creates output data relating to an image suitable for the printing function of the printer.

The CPU 100 has an operation panel 10
3, ROM 104 and RAM 105 are connected. The operation panel 103 sets various parameters such as a paper size and displays them. ROM10
Reference numeral 4 stores various programs necessary for controlling the inkjet printer 1. RAM 105
It temporarily stores print data transferred from the host computer 102 and various numerical values necessary for controlling the ink jet printer 1, and has a backup memory 105a.

The CPU 100 includes an LF drive circuit 11
1. The drive of the LF motor 14, the CR motor 10, and the recording head 5 is controlled via the CR drive circuit 112 and the head drive circuit 113. Further, a signal from a cartridge replacement detection switch 21 provided on the carriage 6 for detecting replacement of the ink cartridge 7 is also input.

The LF motor 14 is configured to drive either the purge mechanism RM or the paper feed mechanism LM via a switching mechanism 121 including a gear that can be disengaged from the drive gear 46. . And the CPU
The control means 100 controls the operation of the suction pump 42 to perform the purge operation.

In one suction operation in which the suction cap 41 is brought into close contact with the nozzle surface of the recording head 5 and the suction pump means 31 suctions ink from the recording head 5, the control means controls the piston member 5.
3, 54 are selectively driven at different speeds. That is, the piston members 53 and 54 are selectively different depending on the combination of the continuous drive and the intermittent drive of the piston members 53 and 54, the combination of the intermittent drive of the piston members 53 and 54 at different periods, or all combinations thereof. It is driven at a speed.

The CR motor 10 drives the carriage mechanism CM, and the carriage 6 of the carriage mechanism CM
, The switching mechanism 121 is switched.

The purge mechanism RM, the paper feed mechanism LM, and the carriage mechanism CM have respective sensors.
A detection signal from the sensor is input to the CPU via a group of counters 122.

The purge mechanism RM has a purge HP sensor 131. When the suction pump 42 is at the home position, the purge HP sensor 131 notifies the counter group 1
22 is notified to the purge position counter 122a. This signal is used as a reference for the purge operation by the purge mechanism.

The paper feed mechanism LM includes a PE sensor 132
The PE sensor 132 emits a signal at the leading end of the newly supplied printing paper 4, and outputs the L signal of the counter group 122.
Notify the F position counter 122b. This signal serves as a reference for controlling the recording position in the vertical direction.

The carriage mechanism CM has a CR position sensor 133. The CR position sensor 133 counts driving pulses of the CR motor 10 to detect the position of the carriage, and the CR position counter 122c of the counter group 122.
To inform. The position information serves as a reference for maintaining the horizontal position, and also as a criterion for determining whether or not a new feeding operation of the printing paper 4 and a discharging operation of the printed paper are possible.

The operation of the ink jet printer 1 configured as described above will be described.

First, in the ink jet printer 1, the recording head 5 is usually at a standby position in a state where the recording head 5 is covered with the storage cap 71. When recording data is input, recording is performed.

The printing paper 4 is supplied between the platen roller 3 and the recording head 5, and the recording head 5 is moved from the standby position to the recording start position by the operation of the CR motor 10.

The printing on the printing paper 4 is performed by the recording head 5 being reciprocated in the recording area while ejecting ink based on the recording data. When printing is completed, the recording head 5 is moved to the standby position, and is covered with the storage cap 1 to prevent the nozzle surface from drying while not being used.

When the purge switch on the operation panel 103 is operated by a user's judgment and a purge command is input, a purge mode for operating the purge mechanism RM is entered, and a suction operation program is executed as described later. You.

By the way, the purge switch is operated when an ink ejection failure occurs, whereby the suction operation is performed by the suction pump 42 as described above. When the ink cartridge 7 is replaced and ink needs to be sucked into the recording head 5 or when the storage cap 7
If the state in which the printing operation is not performed even if the printing operation is continued, the nozzles of the printing head 5 begin to dry, so that in order to ensure a good ejection state, the nozzles are automatically set according to the length of the non-use period. It is also performed when performing maintenance. In other words, when the ink cartridge 7 is replaced, the cartridge replacement detection switch 21 provided on the carriage 6 detects this, and under the control of the CPU 100, a suction operation for sucking ink by replacing the ink cartridge 7 is performed. CPU 100 and ROM 104, RA
When printing is started, the suction operation is automatically performed by the timer means configured by M105 according to the length of the non-use period immediately before printing. In this case, at the time of automatic maintenance, the driving speed of the piston members 53 and 54 is made slower than at the time of purge for recovering ink ejection failure so that the maximum suction negative pressure is reduced. The drive speed is further slowed down than at the time of maintenance, and the maximum suction negative pressure is controlled to be further reduced. According to the state of the nozzles of the recording head 5 and the ink passage, the manner of ink suction is changed as described later. Be changed.

In the purge mode, the carriage mechanism C by the CR motor 10 via the CR drive circuit 112 is first controlled by the CPU 100 based on the suction operation program.
By driving M, the recording head 5 is moved from a position facing the storage cap 71 to a position facing the suction cap 41. When in the recovery area, the switching mechanism 121 has already switched the LF motor 14 to a state where the driving force can be transmitted to the purge mechanism RM.
Then, the cam member 43 is rotated by the driving force from the LF motor 14, and the wiper member 32, the suction cap 41, and the suction pump 42 are controlled. The recovery operation, that is, the operation of bringing the suction cap 41 and the wiper member 32 into and out of contact with each other, and the suction pump 42 perform the suction / discharge operation. Here, the suction operation includes the operation of bringing the suction cap 41 into close contact with the nozzle surface and sucking ink from the recording head 5 by the suction pump 42, and the operation of suctioning the suction cap 41 by separating at least a part of the suction cap 41 from the nozzle surface. A so-called idle suction operation of sucking ink from the inside of the cap 41 is included.

Next, the operation of bringing the suction cap 41 and the wiper member 32 into and out of the recording head 5 and the operation of suctioning / discharging by the suction pump 42 will be described with reference to FIGS. Will be described along with the change in the rotation angle of

First, when the rotation angle of the cam member 43 is near 0 °, both piston members 53, 54 of the suction pump 42 are set.
In the initial state, the pump chamber 52e is located near the discharge port 52b while minimizing the volume of the pump chamber 52e therebetween, and the suction cap 41 is located at the standby position away from the recording head 5 (FIG. 6 ( a)).

Then, when the cam member 43 is driven to rotate, the first and second piston members 53, 54 gradually move forward integrally with the cam member 43 from a rotation angle of about 6 °.
The moving speed is slightly increased near ゜ (see FIG. 6B).

When the rotation angle of the cam member 43 becomes about 114 °, the piston members 53 and 54 stop moving, and the pump chamber between the piston members 53 and 54 becomes near the suction port 52a (FIG. 6 ( c)).

On the other hand, when the rotation angle of the cam member 43 approaches 57 ° during the forward movement of the piston members 53 and 54, the suction cap 41 is moved from the standby position to the recording head 5 as shown in FIG. The suction cap 41 gradually covers the nozzle surface of the recording head 5 at about 86 °.

After the suction cap 41 completely covers the nozzle surface of the recording head 5, the first piston member 5
1 maintains the state of FIG. 6C from 114 ° to 130 ° when the rotation angle of the cam member 43 changes from 130 ° to 205 °, while the first piston member 53 remains stationary while the second piston member 53 remains in the second state. The piston member 54 is moved backward in the direction in which the distance between the first piston member 53 and the first piston member 53 increases, and the pump chamber 52e between the first and second piston members 53 and 54 is enlarged (FIG. 6D), and the suction is performed. The operation is performed. In this suction operation, the piston member 54 is driven continuously and intermittently,
Alternatively, the suction force is controlled by intermittent driving at different cycles.

Specifically, control is performed by changing the piston member 54 by a fixed stroke amount at a fixed cycle and finally at a target interval. When the ink cartridge 7 is replaced, the speed is further reduced than when the automatic maintenance is performed. That is, the LF motor 14 that drives the purge mechanism RM and the switching mechanism 121 including the cam member 43 associated with the piston members 53 and 54 has C
PU 100 is associated, the cam member 43 changes the speed of the piston member 54 by temporarily stopping its rotation, and the CPU 100 has another timer means (not shown), By changing the stop time, the ink suction mode can be changed according to the state of the nozzles of the recording head 5 and the ink path.

More specifically, in the suction operation in which the rotation angle of the cam member 43 is 130 ° to 205 °, the suction port 52 is
By selectively driving the piston member 54 at different speeds in a state where a is communicated with the pump chamber 52e, the maximum suction negative pressure is changed while maintaining the ink suction amount,
The manner in which the ink is sucked can be changed according to the state of the nozzles of the recording head 5 and the ink passage. As an example, at the time of normal purging, FIG.
As shown in FIG. 7, the second piston member 54 is moved without temporarily stopping the cam member 43, and the pump chamber 52 is moved.
e is increased to increase the maximum suction negative pressure, and the suction is performed at a stretch with a large suction force. Also, at the time of automatic maintenance, FIG.
(B) As shown in (c) and (d), 50 m each of 10 °
The rotation is performed after waiting for s, 100 ms or 200 ms, the maximum suction negative pressure is made slightly lower than in the case described above, and suction is performed with a slightly smaller suction force. 8B, 8C, and 8D are selectively executed according to the length of non-use time of the printer. Further, when replacing the ink cartridge 7, FIG.
As shown in (e), the suction is rotated by 10 ° at a time of 300 ms, and the suction is gradually performed with a smaller suction force without increasing the maximum suction negative pressure so much.

Here, at the time of automatic maintenance or replacement of the ink cartridge, the maximum negative suction pressure is set to be smaller than at the time of normal purging operation to perform suction. Since there is a high possibility that the ink passage between the recording head 5 and the ink cartridge 7 is filled with air, when the suction pump 42 performs a suction operation, a large suction force is applied through the suction cap 41. To cause the ink of the recording head 5 to be sucked at a stretch as in the case of the so-called normal purging operation, the ink rapidly flows into the recording head 5 in a state of being mixed with air, and the ink foams, This is because bubbles in the ink in the recording head 5 are included. In particular, in the case where the filter member 19 is provided at the connection portion between the recording head 5 and the ink cartridge 7 so that dust and the like do not move together with the ink on the recording head 5 side as described above, as in the present embodiment. This is because the tendency is remarkable.

Therefore, as shown in FIG. 8E, the filter member 19 is gradually sucked with a small suction force.
In addition, the ink can be slowly passed through the ink passage to suppress bubbling, and the recording head 5 can be filled with ink containing no air bubbles.

At the time of automatic maintenance, since the ink path between the ink cartridge 7 and the recording head 5 is filled with ink, the ink does not foam even with a slightly large suction force, but the ink dries. Due to the rising state, even a small suction force as described above is enough to remove the ink having a slightly higher density.

Then, the rotation angle of the cam member 43 becomes 205
From ゜ to 239 °, the state is maintained. From 239 ° to 272 °, the second piston member 54 is connected to the discharge port while the first piston member 53 keeps the suction port 52a open. It is moved backward just before opening 52b (see FIG. 6E), and the suction operation is performed while further expanding the pump chamber 52e. On the other hand, the suction cap 41
Starts to separate from the recording head 5 at 250 ° and is opened to the atmosphere. By this suction operation, ink remaining in the suction cap 41 and the suction pipe 55 is sucked.

Then, during the period from the cam members 272 # to 282 #, the second piston member 54 continues to retreat in the direction of opening the discharge port 52b, while the first piston member 53 closes the suction port 52a. Move backward in the closing direction. Then, as shown in FIG. 6 (f), the second piston member 54 moves backward to a position where the pump chamber 52e is opened to the discharge port 52b, and stops moving when the rotation angle of the cam member 43 is around 282 °. The first piston member 53 continues the retreating movement until the rotation angle of the cam member 43 becomes about 338 °, compresses the pump chamber 52e, and positively performs the discharging operation (see FIG. 6G). ). As a result, the ink in the pump chamber 52e is discharged to the waste ink tank 58.

After the discharging operation, the two piston members 53 and 54 are kept stopped until the cam member 43 moves from 338 ° to 345 °.
3 and 54 move forward slightly, as shown in FIG. 6 (h), and are returned to the same state as the initial state.
゜ is maintained from 360 ° (0 °) to the initial state.

Further, the wiper member 32 maintains the standby state from the rotation angle of the cam member 43 of 0 ° to 287 °.
It gradually advances from 7 ° to 300 °, reaches a protruding position at 300 °, maintains the protruding position from 300 ° to 320 °, and wipes the nozzle surface of the recording head 5 moving to the recording area side (FIG. 7). Then, it gradually retreats from 320 ° to 333 °, becomes the standby position, and becomes 360 ° as it is.

In the above-described embodiment, only one rotation of the cam member 43 is performed in one recovery process. However, the present invention is not limited to this. The cam member 43 may be configured to rotate a plurality of times. In other words, in order to ensure the recovery, the suction operation is repeated by continuously rotating the cam member 43 twice or more. When the ink cartridge is replaced, the suction operation of FIG. 8E may be repeated. However, since the ink passage is filled with ink for the second and subsequent times, the suction operation may be repeated with a large suction force. In this manner, the recording head 5 can be reliably filled with ink.

Further, in the above embodiment, the second piston member 54 is changed by a predetermined stroke at a predetermined cycle in the suction operation, but one or both of the two piston members are similarly moved. Or may be continuously moved at a low speed. Further, the suction pump means used in the present invention has a piston member movable in the cylinder body, and the control means makes the suction cap adhere to the nozzle surface and suctions ink from the recording head by the suction pump means. In one suction operation, the piston member may be selectively driven at different speeds, and the number of piston members may be one.

[0075]

The present invention is embodied in the form described above, and has the following effects.

According to the first aspect of the present invention, as described above, in one suction operation in which the suction cap is brought into close contact with the nozzle surface and the ink is sucked from the recording head by the suction pump means, the piston member is selected by the control means. The speed at which the piston member is driven is changed according to the state of the nozzles and ink passages of the recording head, thereby ensuring a constant ink suction amount, And an ink suction mode suitable for the state of the ink passage. In addition, since it can be easily realized only by changing the control with one pump, it can be provided at low cost.

According to the second aspect of the present invention, the different speeds are obtained by continuously and intermittently driving the piston member or intermittently at different periods.
A wide variety of speeds for driving the piston member can be obtained simply.

According to the third aspect of the present invention, the interval between the two piston members of the suction pump means is changed at a constant cycle by a constant stroke amount so as to finally reach the target interval. By changing the stroke amount, the ink suction mode can be easily changed, and
Irrespective of the ink suction mode, a constant ink suction amount can be secured.

According to the fourth aspect of the present invention, at the time of automatic maintenance, the speed is made slower than at the time of purging for recovering ink discharge failure, so that ink is sucked with a predetermined suction force without foaming. When the ink cartridge is replaced, the speed is further reduced compared with the time of the automatic maintenance. Therefore, the ink can be sucked while suppressing foaming of the ink as much as possible.

According to the fifth aspect of the present invention, the driving means is controlled by the control means, the cam member is driven to rotate at a predetermined timing, and the piston member is selectively driven at different speeds. The structure allows the piston members to be selectively driven at different speeds.

According to a sixth aspect of the present invention, the speed of the piston member is changed by temporarily stopping the rotation of the cam member, and the time of the temporary stop is changed by the control means. With a simple control of changing the time during which the rotation of the member is temporarily stopped, the ink suction mode can be changed according to the state of the nozzles of the recording head and the ink passage.

According to a seventh aspect of the present invention, in addition to the one suction operation, an idle suction operation in which at least a part of the suction cap is separated from the nozzle surface of the recording head and ink is sucked from the inside of the suction cap by the suction pump means. Since the operation is performed, the ink remaining in the suction cap can be removed by suction.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating a schematic configuration of an ink jet printer according to the present invention.

FIG. 2 is a sectional view of a connection portion between a recording head and an ink cartridge according to the present invention.

FIG. 3 is a cross-sectional view showing a relationship among a wiper member, a suction cap, a suction pump, and a cam member according to the present invention.

FIG. 4 is a sectional view showing a suction pump according to the present invention.

FIG. 5 is a block diagram of a control unit of the inkjet printer.

FIGS. 6A to 6J are explanatory diagrams of the operation of the suction pump.

FIG. 7 is a diagram illustrating the rotation angle of a cam member and the operation of a suction cap, a wiper member, and a suction pump.

FIG. 8 is an explanatory diagram of a mode of a change in negative suction pressure by a suction pump unit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ink jet printer 5 Recording head 14 LF motor 32 Wiper member 41 Suction cap 42 Suction pump 43 Cam member 100 CPU

Claims (7)

[Claims] An ink jet head for ejecting ink to a recording medium to perform recording; and a suction cap having a suction cap which comes into contact with a nozzle surface of the print head so as to be capable of coming into contact with and separating from the nozzle face. A recovery device for an ink jet printer, comprising: a pump unit; and a control unit for controlling the driving of the suction pump unit. The suction pump unit has a piston member movable in a cylinder body, and the control unit includes the suction unit An ink jet printer, wherein the piston member is selectively driven at different speeds in one suction operation in which a cap is brought into close contact with a nozzle surface to suction ink from the recording head by the suction pump means. Recovery device. 2. The recovery of an ink jet printer according to claim 1, wherein said control means obtains said different speeds by continuously and intermittently driving said piston member or intermittently at different periods. apparatus. 3. The piston member according to claim 2, wherein said piston member is relatively movable.
The control means controls the suction pump means to change the interval between the two piston members by a constant stroke amount at a constant cycle to finally set a target interval. 3. The ink jet printer recovery device according to claim 2, wherein: 4. The control means controls the suction pump means to make the speed lower at the time of automatic maintenance than at the time of purge for recovering ink ejection failure, and at the time of replacement of an ink cartridge, at the time of automatic maintenance. Wherein the speed is further reduced.
4. The recovery device for an ink jet printer according to any one of 3. 5. The apparatus according to claim 1, further comprising a cam member associated with said piston member, and driving means for rotating said cam member, said control means being associated with said driving means. 5. The recovery device for an ink jet printer according to any one of 4. 6. The apparatus according to claim 1, wherein the cam member changes the speed of the piston member by temporarily stopping the rotation, and the control means changes the time of the stop. The recovery device for an ink jet printer according to any one of claims 1 to 5. 7. The idle suction operation in which at least a part of the suction cap is separated from a nozzle surface of a recording head and ink is sucked from inside the suction cap by suction pump means in addition to the one suction operation. The recovery device for an inkjet printer according to claim 5, wherein the recovery is performed.