JP2004025897A - Recovery unit of inkjet printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a recovery unit of an inkjet printer in which ink suction mode can be altered depending on the conditions of a nozzle or an ink passage of a recording head. <P>SOLUTION: A cam member has a plurality of cam parts causing a suction pump to perform a plurality of suction operations during a single rotation thereof. Suction operation is performed a plurality of times for each cam part with a low suction force and a short suction time by stopping rotation of the cam member at the position of each cam part. Suction by the cam part and suction by a following cam part are performed at a breath by not stopping rotation of the cam member at the position of the cam part thus performing suction operation with a high suction force and a long suction time. <P>COPYRIGHT: (C)2004,JPO

Description

The present invention relates to a recovery device for an inkjet printer that performs recording by ejecting ink onto a recording medium.

Conventionally, a recording head that performs recording by ejecting ink to a recording medium, a suction pump having a suction cap that comes into contact with and detachable from a nozzle surface of the recording head, and suctioning ink of the recording head through the suction cap, An ink jet printer including a control means for controlling the drive of the suction pump means is known.

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 causes the ink in the recording head to pass through the suction cap. It is performed by sucking at a stretch.

However, in the use of such an ink jet printer, when exchanging an ink cartridge including when the ink cartridge is connected to the recording head for the first time, the ink passage between the recording head and the ink cartridge may be filled with air. In such a state, a large suction force is applied through the suction cap to suction the ink of the print head at a stretch in such a state, as in the case of the normal purge operation for recovering the ejection failure during the printing operation. In this case, the ink flows rapidly from the ink cartridge toward the recording head in a state of being mixed with the air, and the ink foams, and the ink in the ejection channel of the recording head contains bubbles. This tendency is particularly remarkable 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. .

Therefore, when exchanging the ink cartridge or the like, there is a demand that the ink be sucked from the recording head in such a manner that the foaming does not occur.

On the other hand, when the nozzles of the recording head have a discharge failure due to drying of the ink, clogging of dust, or the like, it is desirable to suck the ink in the recording head at a stretch with a large negative pressure. Further, 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. .

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a recovery device for an ink jet printer that can change the mode of ink suction according to the state of nozzles and ink passages of a recording head. I do.

According to a first aspect of the present invention, there is provided a recording head that performs recording by ejecting ink to a recording medium, and a suction cap that comes into contact with the nozzle surface of the recording head so as to be able to come and go. Suction pump means, and a recovery device for an ink jet printer comprising a control means for driving and controlling the suction pump means,
The suction pump means includes a piston member movable in a pump housing and configured to vary a volume of a pump chamber for sucking ink from the suction cap, and a cam member associated therewith to move the piston member. ,
The cam member includes a cam portion having a first portion that moves the piston member in a direction in which the pump chamber expands and a second portion that stops the movement of the piston member in the expanded state. In one rotation, it has a plurality in the rotation direction,
The control means is configured to perform the suction operations by the respective cam portions independently and sequentially, and to selectively perform the suction operations by the two adjacent cam portions substantially at once. It controls the rotation of the member.

The invention according to claim 2 is the device according to claim 1, wherein, of the two adjacent cam portions, a cam portion located at a later stage in the rotational direction of the cam member is enlarged by a cam portion located at an earlier stage thereof. The piston member is moved in a direction in which the pump chamber is further enlarged.

According to a third aspect of the present invention, in the device according to the second aspect, the control means temporarily stops rotation of the cam member at a position where the piston member corresponds to a second portion of the cam portion. One suction operation is performed in the cam portion, and in the second portion of the cam portion, the rotation of the cam member is not stopped so that each suction operation of the cam portion and the subsequent cam portion is performed almost at once. Things.

According to a fourth aspect of the present invention, in the device according to any one of the first to third aspects, the pump housing includes a suction port connected to the suction cap, and a discharge port axially spaced from the suction port. Has,
The piston member includes first and second piston members that form the pump chamber therebetween,
While performing each suction operation by each of the adjacent cam parts, the pump chamber between the first and second piston members is connected to the suction port, and the pump chamber is enlarged for each suction operation. The second piston member is moved in a direction in which the discharge port is connected to the pump chamber, and the first piston member is moved in a direction in which the suction port is closed with respect to the pump chamber.

According to a fifth aspect of the present invention, in the apparatus according to any one of the first to fourth aspects, the control means rotates the cam member a plurality of times, and makes the cam member independent of one rotation and the subsequent rotation. Each suction operation performed at a stretch is included differently.

According to the first aspect of the present invention, as described above, the cam member includes the first portion for moving the piston member in the direction in which the pump chamber expands and the second portion for stopping the movement of the piston member in the expanded state. A plurality of cam portions are provided in the rotation direction within one rotation of the cam member, and by controlling the rotation of the cam member, each suction operation by each cam portion is performed independently and sequentially, and It is possible to selectively perform each suction operation by the two adjacent cam portions at a stretch, thereby controlling the suction force and the suction time performed by the suction pump means, and controlling the nozzles and ink of the recording head. The manner of ink suction can be changed according to the state of the passage.

According to a second aspect of the present invention, in the two adjacent cam portions, the pump chamber expanded by the front cam portion in the rotation direction is further expanded by the rear cam portion, so that a large suction is performed in each of the suction operations performed at a stretch. You can gain power.

According to a third aspect of the present invention, the rotation of the cam member is temporarily stopped at a position where the piston member corresponds to the second portion of the cam portion, so that the first portion of the cam portion enlarges the pump chamber. One suction operation can be reliably performed. Also, in the second portion of the cam portion, the suction operation of the cam portion and the succeeding cam portions can be performed almost at once by not stopping the rotation of the cam member, so that a large suction force can be obtained.

According to a fourth aspect of the present invention, the pump chamber between the first and second piston members is connected to the suction port while performing each suction operation by the adjacent cam portions, and in that state, the pump chamber is connected for each suction operation. By enlarging, it is possible to reliably perform each suction operation that is performed independently or almost at once, and then close the suction port and discharge the ink through the discharge port.

According to the fifth aspect of the present invention, the cam member is rotated a plurality of times, and the one rotation and the subsequent rotation include the suction operations performed independently or substantially at once at different times, so that the suction force and the suction time are reduced. The suction operation can be performed in different modes.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic perspective view showing the overall configuration of the ink jet printer. In FIG. 1, the inkjet printer 1 has a cylindrical platen roller 3 rotatably supported on a frame 2 by a rotating shaft (not shown) extending in the left-right direction. The platen roller 3 transports the printing paper 4 (recording medium) supplied from a paper feeding cassette or a manual paper feeding unit while facing the recording head 5, and constitutes a part of a so-called paper feeding mechanism LM. ing. The recording head 5 is of an ink jet type having nozzles 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 rotation of the platen roller 3, and is supplied from a paper discharge port (not shown). It is configured to be 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, a recording head 5 and an ink cartridge 7 having heads for four colors of yellow, black, cyan, and magenta are respectively 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 ink cartridge 7 is connected to the recording head 5 supported by the head supporting member 16 via the manifold member 15. It is supposed to be. The rear end of the manifold member 15 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 portion, an ink supply hole 7a of the ink cartridge 7 and an adapter 18 are provided, and a net-like filter member 19 is provided on the recording head 5 side so that dust and the like do not move with the ink.

A carriage shaft 8 is provided in parallel with the axis of the platen roller 3, and the 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. Thus, the recording head 5 mounted on the carriage 6 can reciprocate by sliding along the axis of the platen roller 3. The carriage 6 is fixed to a part of the timing belt 11, and the timing belt 11 is wound around the timing pulleys 12 and 13 to form a carriage mechanism CM. Motor) is connected. Thus, the rotation of the CR motor 10 causes the carriage 6 to reciprocate in the recording area where recording is performed on the printing paper via the carriage mechanism CM. The carriage mechanism CM and the CR motor 10 constitute moving means for moving between the recording area and 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. . 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).

{Circle around (4)} 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 arranged. The reason why such a purge mechanism RM is provided is that the ink jet recording head 5 causes a discharge failure due to a cause such as generation of air bubbles inside the ink or drying of the ink during use. This is for restoring a good ejection state.

A flushing area in which the waste ink receiving member 22 is provided is formed on the left side of the recording area corresponding to the platen roller 3. Such a waste ink receiving member 22 is provided just before the recording operation by the recording head 5 in order to eliminate clogging of the nozzles of the recording head 5 and to remove bubbles mixed with ink in the nozzles. This is for preliminarily discharging ink.

The purge mechanism RM is movable between a protruding position protruding into the moving path of the recording head 5 and a standby position retracted from the moving path of the recording head 5, and is in close contact with the nozzle surface of the recording head 5 at the protruding position. And a suction pump 42 for sucking and removing ink in the recording head 5 through the suction cap 41 when the suction cap 41 is in close contact with the nozzle surface of the recording head 5 at the protruding position. 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 toward the recording area is used when the recording head is not recording on the opposite side. The storage cap devices 33 which cover the nozzle surfaces of No. 5 and prevent evaporation of the ink to avoid drying of the nozzle surfaces are provided.

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

As shown in FIG. 3, the cam member 43 has a drive gear 46 provided integrally, and is driven to rotate by driving means such as a motor. For example, the drive gear 46 is configured to be removably engaged with a drive gear (not shown) that is rotationally driven by the LF motor 14 of the paper feed mechanism LM. Are driven to rotate forward.

Further, the rear end (cam follower) of the wiper holder 34 supporting 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 projecting position protruding into the path and a standby position retracted from the moving path of the recording head 5. 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 cam groove of the cam member 43 on the same plane as the first cam groove 43a. 43b so as to be movable.

The suction pump 42 has a first and second piston members 53 and 54 which are independently and movably fitted into a cylindrical pump housing 52 which is attached and fixed to a frame member 51. 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, and the discharge port 52b Are linked to a waste ink tank 58 containing an ink absorbing material 57 (see FIG. 1). One end of the pump housing 52 is an atmosphere opening portion 52c that is open to the atmosphere, and a first piston member 53 is disposed on the side of the atmosphere opening portion 52c.

The first and second piston members 53 and 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, respectively. A pump chamber 52e is formed between the piston members 53 and 54.

The first drive shaft member 61 is slidably fitted into the second drive shaft member 62, and the other end of each of the drive shaft members 61, 62 has an opposite surface to the cam grooves 43a, 43b. The cam member 43 is movably engaged with the third and fourth cam grooves 43c and 43d. The cam grooves 43c and 43d (cam portions) of the cam member have a shape corresponding to a plurality of suction operations, and the cam member 43 is rotated or temporarily stopped as described later. Is changed, the suction force and the suction time of the suction operation performed by the suction pump 42 are controlled.

Therefore, when the cam member 43 is rotationally driven at a certain 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. The ink sucked by the suction pump 42 is discharged to the waste ink tank 58 via the suction pump 42, and is absorbed by the ink absorbing material 57 in the waste ink tank 58.

As shown in FIG. 1, the storage cap device 33 has a storage cap 71 that covers each head of the recording head 5, and a casing 72 that supports the storage cap 71 is parallel to the moving direction of the carriage 6. The extending guide rod member 73 is supported so as to be able to slide and rotate. Further, the casing 72 is engaged with the carriage 6 when the carriage 6 moves to the outside of the recording area, and has an engagement protrusion 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 side, 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). During this sliding movement, the storage cap 71 rotates around the guide rod 73 by the action of the not-shown tilt cam means. As a result, the storage cap 71 rotates in a direction approaching the recording head 5, and the storage cap 71 The capping is performed by contacting the nozzle surface. 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 unit of the inkjet printer 1 according to the embodiment will be described with reference to the block diagram of FIG. This control unit is mainly configured by a CPU 100 which is a well-known arithmetic processing device. The CPU 100 is connected to a host computer 102 such as a personal computer via an interface 101, receives a print command from the host computer 1102, and executes various printings in accordance with the command.

ウ イ ン ド ウ A typical window system is a functional configuration of the host computer 102. Various applications (A), (B),... (N) are provided on this window system, 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 operation panel 103, the ROM 104, and the RAM 105 are connected to the CPU 100. The operation panel 103 sets a paper size and other various parameters and displays them. The ROM 104 stores various programs necessary for controlling the inkjet printer 1. The RAM 105 temporarily stores print data transferred from the host computer 102 and various numerical values required for controlling the ink jet printer 1, and has a backup memory 105a.

The CPU 100 controls the drive of the LF motor 14, the CR motor 10, and the recording head 5 via the LF drive circuit 111, 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. The CPU 100 constitutes control means for controlling the operation of the suction pump 42 to perform the purging operation.

As shown in FIG. 8A, the suction pump 42 can perform a plurality of suction operations in a series of operations, and the CPU 100 controls the suction pump 42 via a cam member 43. By controlling the suction operation, the plurality of suction operations are selectively combined to change the suction force together with the number of suction operations. For example, when the ink cartridge 7 is replaced, a plurality of suction operations with a small suction force and a short suction time are performed in order to suck the ink without causing the problem of bubbling. In order to maintain the discharge state, a suction operation is performed in which the suction force is relatively large and the suction time is relatively long. In the case of a discharge failure, a suction operation with a large suction force and a long suction time is performed to recover the discharge failure.

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

The purge mechanism RM, the paper feed mechanism LM, and the carriage mechanism CM have respective sensors, and detection signals from the sensors are input to the CPU via a group of counters 122. The purge mechanism RM includes a purge HP sensor 131. When the suction pump 42 is at the home position, the purge HP sensor 131 notifies the purging position counter 122a of the counter group 122 of the fact. This signal is used as a reference for the purge operation by the purge mechanism.

The paper feed mechanism LM has a PE sensor 132. The PE sensor 132 issues a signal at the leading edge of the newly supplied printing paper 4 and notifies the LF position counter 122b of the counter group 122. 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 the drive pulses of the CR motor 10, detects the position of the carriage, and notifies the CR position counter 122c of the counter group 122. This position information serves as a reference for controlling the horizontal position to be maintained, and also as a reference for determining whether or not a new supply operation of the printing paper 4 and an operation of discharging the printed paper are possible.

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

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

(4) 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 is performed on the printing paper 4 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.

In addition, for example, in the case where ink ejection failure occurs, the purge switch on the operation panel 103 is operated by a user's judgment, and when a purge command is input, a purge mode for operating the purge mechanism RM is entered. Then, the suction operation program is executed.

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. Is replaced, and if it is necessary to suck ink into the recording head 5 or if the recording operation is not performed even with the storage cap 71, the nozzles of the recording head 5 begin to dry. In order to ensure a proper discharge state, the maintenance is automatically performed according to the length of the non-use period. That is, when the ink cartridge 7 is replaced, the cartridge replacement detection switch 21 provided on the carriage 6 detects the replacement, and the suction operation for ink suction by replacement of the ink cartridge 7 is performed under the control of the CPU 100. In addition, when printing is started, the suction operation is automatically performed according to the length of the non-use period immediately before printing by the timer means including the CPU 100, the ROM 104, and the RAM 105.

In the purge mode, based on the suction operation program, first, the CPU 100 drives the carriage mechanism CM by the CR motor 10 via the CR drive circuit 112 so that the recording head 5 faces the suction cap 41 from the position facing the storage cap 71. Is moved to the position where 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, and the suction / discharge operation by the suction pump 42 are performed. 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 explained along with the change of

First, when the rotation angle of the cam member 43 is near 0 °, the two piston members 53 and 54 of the suction pump 42 minimize the volume of the pump chamber therebetween and the pump chamber is located near the discharge port 52b. The suction cap 41 is in an initial state located at a standby position away from the recording head 5 (see FIG. 7).

Then, when the cam member 43 is driven to rotate, the first and second piston members 53 and 54 gradually move integrally from around 6 ° to around 57 ° (FIG. 6B). (See Ref.), Slightly decrease the moving speed and increase the speed around 97 °. On the other hand, when the rotation angle of the cam member 43 approaches 57 ° during the movement of the piston members 53 and 54, the suction cap 41 is moved from the standby position to the movement path side of the recording head 5 as shown in FIG. The suction cap 41 covers the nozzle surface of the recording head 5 at around 86 °.

When the rotation angle of the cam member 43 becomes about 108 ° (see FIG. 6C), the second piston member 54 stops moving, only the first piston member 53 continues to move, and the pump chamber 52e is enlarged and the suction port 52a is opened (see FIG. 6D). Then, the first piston member 53 stops around 114 °, and the state in which the movement of both piston members 53 and 54 stops until 121 ° is maintained. At this time, the first suction operation is performed by stopping the rotation of the cam member 43 near 121 ° (position A) for a certain time (3 seconds) (FIG. 8A to FIG. 8D). reference).

Then, both piston members 53 and 54 move to the outlet 52b side, and the first piston member 52a closes the inlet 52a and stops (see FIG. 6E). The rotation angle of the cam member 43 is maintained until 158 °, and while the rotation angle of the cam member 43 changes from 158 ° to 164 °, the second piston member 53 remains stationary while the first piston member 53 is in contact with the second piston member 54. Is moved in the direction in which the distance between the first and second piston members 53 and 54 is expanded, and the suction port 52a is opened while the pump chamber 52e is opened again (see FIG. 6F). The state where the movement of the piston members 53 and 54 is stopped is maintained. At this time, the rotation of the cam member 43 is stopped for a predetermined time (3 seconds) near 171 ° (position B), whereby the second suction operation with a small suction force and a short suction time is performed (FIG. 8). (B) of (a) and (c)).

Then, from 179 ° to 184 °, the second piston member 54 moves away from the first piston member 53 (see FIG. 6G), and the pump chamber 52e is enlarged to 184 °. And the first and second piston members 53 and 54 maintain the stopped state until 200 °. At this time, the rotation of the cam member 43 is stopped for a predetermined time (3 seconds) near 192 ° (position C), so that a third suction operation with a small suction force and a short suction time is performed (FIG. 8). (See c in (a)). When the cam member 43 is stopped at the position C for a predetermined time (5 seconds) without being temporarily stopped at the position B, the cam member 43 normally rotates at a speed of rotating 360 ° in 3 seconds. Although the negative pressure appears momentarily, the enlargement of the pump chamber 52e from 164 ° to 184 ° is almost the same as that performed at a stretch, and the enlargement of the pump chamber 52e makes the suction more than when stopped at the position B. The negative pressure is increased, and a suction operation is performed in which the suction force is large and the suction time is relatively long (see E in FIG. 8B).

Further, the second piston member 54 further moves in a direction away from the first piston member 53 from 200 ° to 205 ° (see FIG. 6 (h)), and further enlarges the pump chamber 52e. , 205 ° to 239 °, the first and second piston members 53, 54 maintain the volume of the pump chamber 52e. At this time, the rotation of the cam member 43 is stopped for a predetermined time (3 seconds) near 211 ° (position D), so that a fourth suction operation with a small suction force and a short suction time is performed (FIG. 8). (See (a) d)). If the stop is performed at the position D for a fixed time (3 seconds) without stopping at the position C, the negative pressure appears momentarily at the position of 184 °, but the pump chamber 52e from 184 ° to 205 ° This is equivalent to the fact that the enlargement has been performed at a stretch, the suction negative pressure is increased as compared with the case where the suction is stopped at the position C, and the suction operation with a large suction force and a relatively long suction time is performed (FIG. 8C). ))). Further, if the pump is stopped at the position D for a predetermined time (5 seconds) without being temporarily stopped at the positions B and C, the expansion of the pump chamber 52e from 164 ° to 205 ° is performed almost at once, and the suction load is reduced. The suction operation is performed in which the pressure is greatly increased, the suction force is large, and the suction time is long (see FIG. 8D).

From 239 ° to 272 °, the second piston member 54 further moves in a direction away from the first piston member 53 (see FIG. 6 (i)), and a suction operation is performed. 53 also moves following the second piston member to close the suction port.

Then, at around 282 °, the second piston member 54 stops in a state where the discharge port 52b is opened (see FIG. 6 (j)), but the first piston member 53 controls the movement by the rotation angle of the cam member 43. Is maintained around 338 °, the pump chamber 52e is compressed, and the pumping operation is actively performed (see FIG. 6 (k)). As a result, the ink in the pump chamber 52e is discharged to the waste ink tank 58.

On the other hand, the suction cap 41 is kept in close contact with the nozzle surface of the recording head 5 from 86 ° to about 250 °, gradually retracted from 250 ° to 268 °, and slightly moved to 298 °. To retreat further and return to the initial state. Therefore, the movement of the piston members 53 and 54 from around 250 ° does not suck the ink from the recording head 5 but discharges the remaining ink in the suction cap 41 and the tube 55.

After the discharging operation, the two piston members 53 and 54 maintain the stopped state while the cam member 43 is between 338 ° and 345 °, and thereafter the two piston members 53 and 54 are slightly returned until 354 °, and FIG. ), The state is returned to the same state as the initial state, and the state is maintained from 354 ° to 360 ° (0 °), and becomes the initial state.

Further, the wiper member 32 maintains the standby state when the rotation angle of the cam member 43 is from 0 ° to 287 °, gradually advances from 287 ° to 300 °, becomes the protruding position at 300 °, and from 300 ° to 320 °. During this period, the protruding position is maintained, and the nozzle surface of the recording head 5 moving toward the recording area is wiped (see FIG. 7). It gradually retreats from 320 ° to 333 °, becomes the standby position, and remains at 360 °.

After the nozzle surface of the recording head 5 is wiped by the wiper member 32, first, the recording head 5 is moved to the flushing area, and ink is discharged from all the nozzles of the recording head 5 to the waste ink receiving member 22. Is performed, and then the recording head 5 is moved to the recording start position.

Therefore, as shown in FIG. 8A, basically, four suction operations are performed. However, the CPU 100 determines whether or not the rotation of the cam member 43 is temporarily stopped at the positions B, C, and D. 8B, the suction force can be changed together with the number of suction operations as shown in FIGS. 8B to 8D.

That is, for example, when the ink cartridge is replaced, when the suction pump 42 performs a suction operation while the ink passage between the recording head 5 and the ink cartridge 7 is filled with air, the suction cap 41 is used. When a large negative pressure is applied to suck the ink of the recording head 5 at a stretch, the ink rapidly flows from the ink cartridge 7 toward the recording head 5 in a state of being mixed with air, and the ink foams and the recording head 5 Although the ink inside contains bubbles, as shown in FIG. 8A, by performing four suction operations with a small suction force and a short suction time, the ink cartridge 7 It is possible to gradually suck the ink while expelling the air, and when the ink is sucked, the ink foams and the ink inside the recording head 2 is removed. Situation that includes air bubbles are avoided.

For example, in the first suction operation (a), the ink is suctioned so as to gradually pass through the filter member 19, and in the second suction operation (b), the manifold member 15 is gradually filled with the ink, and in the third suction operation (c). Then, ink can be introduced into a number of channels of the recording head 5, and a predetermined amount of ink can be sucked from the recording head 5 into the suction cap 41 in the fourth suction operation d.

In addition, at the time of maintenance that is automatically performed according to the length of the non-use period before the start of printing, the ink passage between the ink cartridge and the recording head 5 is filled with ink. Since the ink does not foam but only removes the ink that is drying, as shown in FIGS. 8 (b) and 8 (c), the suction operation has a relatively large suction force and a relatively long suction time. And a good ejection state is maintained. 8B and 8C may be appropriately selected according to the length of the non-use period.

Further, at the time of purging to eliminate the ejection failure, as shown in FIG. 8D, a suction operation having a larger suction force and a longer suction time is included. , A good ejection state is restored.

As described above, by changing the ink suction mode at the time of ink cartridge replacement, periodic maintenance, and purge of ejection failure elimination, the optimum state of the nozzles and ink passage of the recording head 5 can be obtained. A suction operation can be performed. 8A to 8D, a suction operation with a small suction force and a short suction time is performed first, but this first suction operation is omitted as necessary. be able to.

一連 Further, a series of operations including the plurality of suction operations is performed a plurality of times according to the purpose. For example, after replacing the ink cartridge 7, the first to fourth suction operations are sequentially performed in the first series of operations, and the ink is introduced into the recording head 5 without foaming as described above. Does not foam the ink, and therefore performs any of FIGS. 8B to 8D. In this manner, the recording head 5 can be reliably filled with new ink and can be discharged. As described above, the purge operation appropriately performed by the key operation of the user and the maintenance operation automatically performed by the printer can be performed a plurality of times by combining FIGS. 8B to 8D. In particular, in the case of automatic maintenance, the number of repetitions may be set according to the length of non-use time.

In the above-described embodiment, the time when the ink cartridge is replaced and the time when the ink cartridge is not replaced are determined based on the presence or absence of a signal from the detection switch 21, but the user may be able to select the key operation. Further, the suction pump means is not limited to one having two piston members, but may be one having one piston member. Furthermore, not only can the piston member be temporarily stopped or driven, but also the speed of the piston member can be changed by changing the rotation speed of the motor.

FIG. 1 is a perspective view illustrating a schematic configuration of an inkjet printer according to the present invention. FIG. 3 is a cross-sectional view of a connection portion between a recording head and an ink cartridge according to the present invention. FIG. 4 is a cross-sectional view illustrating a relationship among a wiper member, a suction cap, a suction pump, and a cam member according to the present invention. It is sectional drawing which shows the suction pump which concerns on this invention. FIG. 2 is a block diagram of a control unit of the inkjet printer. (A)-(j) is operation | movement explanatory drawing of a 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. It is explanatory drawing of the aspect of a change of the suction negative pressure by a suction pump means.

Explanation of reference numerals

DESCRIPTION OF SYMBOLS 1 Ink jet printer 5 Recording head 7 Ink cartridge 14 LF motor 32 Wiper member 41 Suction cap 42 Suction pump 43 Cam member 43c Cam groove 43d Cam groove 52 Pump housing 53 First piston member 54 Second piston member 100 CPU
121 Switching mechanism

Claims (5)

A recording head that performs recording by ejecting ink to a recording medium, a suction pump having a suction cap that comes into contact with and detachable from a nozzle surface of the recording head, and suctioning ink of the recording head through the suction cap; A recovery unit for an ink jet printer comprising a control unit for driving and controlling the suction pump unit;
The suction pump means includes a piston member movable in a pump housing and configured to vary a volume of a pump chamber for sucking ink from the suction cap, and a cam member associated therewith to move the piston member. ,
The cam member includes a cam portion having a first portion that moves the piston member in a direction in which the pump chamber expands and a second portion that stops the movement of the piston member in the expanded state. In one rotation, it has a plurality in the rotation direction,
The control means is configured to perform the suction operations by the respective cam portions independently and sequentially, and to selectively perform the suction operations by the two adjacent cam portions substantially at once. A recovery device for an inkjet printer that controls the rotation of members. Of the two adjacent cam portions, the cam portion located at the subsequent stage in the rotation direction of the cam member is configured to move the piston member in the direction in which the pump chamber enlarged by the cam portion located at the preceding stage is further enlarged. The recovery device for an ink jet printer according to claim 1, wherein the recovery device is moved. The control means causes the cam member to perform one suction operation by temporarily stopping the rotation of the cam member at a position where the piston member corresponds to the second portion of the cam portion. 3. The ink jet printer recovery device according to claim 2, wherein, in the second portion, the suction operation of the cam portion and the succeeding cam portion is performed almost at once by not stopping the rotation of the cam member. The pump housing has a suction port connected to the suction cap, and a discharge port axially spaced from the suction port,
The piston member includes first and second piston members that form the pump chamber therebetween,
While performing each suction operation by each of the adjacent cam parts, the pump chamber between the first and second piston members is connected to the suction port, and the pump chamber is enlarged for each suction operation. 4. The method according to claim 1, wherein the second piston member is moved in a direction in which the discharge port is connected to the pump chamber, and the first piston member is moved in a direction in which the suction port is closed with respect to the pump chamber. The recovery device for an ink jet printer according to any one of the above. 5. The control device according to claim 1, wherein the control unit rotates the cam member a plurality of times, and includes different suction operations performed independently or substantially at a time in one rotation and a subsequent rotation. Inkjet printer recovery device.

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