JPH11170570A - Ink jet recording apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily select the operation and non-operation of an ink sucking pump unit used in the cleaning operation of a recording head. SOLUTION: A tube 15A is arranged in a pump frame 42 and a pair of rollers 45A, 45B are supported on a rotary pump wheel 43 in a rotatable manner by roller support grooves 44A, 44B. A pair of the rollers 45A, 45B are guided to a first position E or a second position F corresponding to the position of the roller guide 56 moved by a cam mechanism 51 and the pump action squeezing the tube 15A by the pressure contact with the tube 15A and the operation not brought to the pressure contact with the tube 15A are selected. Therefore, the operation and non-operation of the pump can be controlled corresponding to the cam shape of the cam mechanism 51.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus having a recording head which moves in the width direction of a recording sheet, and which prints an image by discharging ink droplets onto the recording sheet based on print data. More particularly, the present invention relates to a structure of a pump unit for supplying a negative pressure to capping means for eliminating clogging of a nozzle opening of a recording head.

[0002]

2. Description of the Related Art With the development of personal computers, graphic processing has become relatively easy to execute. Therefore, there is a demand for a recording apparatus capable of outputting a hard copy of, for example, a color image displayed on a display with high quality.

[0003] In order to meet such a demand, a recording apparatus equipped with an ink jet recording head has been provided.
This ink jet recording device has low noise during printing and can form small dots with high density.
It is used for many printings, mainly for color printing.

[0004] Such an ink jet recording apparatus is
An ink jet recording head that receives supply of ink from an ink cartridge, and a paper feeding unit that relatively moves the recording paper with respect to the recording head, are provided with ink droplets on the recording paper while moving the recording head according to a print signal. Is ejected to form dots to perform recording.

As described above, in order to prevent the clogging due to the filling of the recording head with the ink and the volatilization of the ink solvent, there is a process for forcibly sucking and discharging the ink from the recording head. In addition, an operation is performed in which a drive signal irrelevant to print data is supplied and ink droplets are ejected from the nozzle openings of the head in the non-print area.

[0006] Forcible ejection of ink to eliminate clogging of the recording head is usually called a cleaning operation, and is performed when printing is resumed after a long period of suspension of the recording apparatus, or when the user prints faint. This is executed when the cleaning switch is pressed in order to eliminate the print quality defect.

In this cleaning operation, the recording head is sealed by capping means and a negative pressure is applied to discharge ink from the nozzles of the head, and thereafter, a wiping member made of an elastic plate such as rubber is used.
A sequence for wiping the head plate is executed.

On the other hand, an operation of applying a drive signal to the recording head to eject ink is generally called a flushing operation, and a cleaning operation is performed to recover an irregular meniscus near the nozzle opening of the head by wiping or the like, or to perform printing. This is an operation to be executed at regular intervals in order to prevent clogging of the nozzle opening in which ink droplets are not ejected.

The application of a negative pressure to the recording head in the above-described cleaning operation is performed by driving a suction pump. This suction pump uses a so-called tube pump, which has a relatively simple structure and is easy to miniaturize.

FIG. 7 shows an example of a conventional unit for driving a tube pump and a wiping member.

The pump unit 91 is provided with a pump frame 91c having cylindrical portions 91a and 91b formed on both outer sides thereof. Pump wheels 91d and 91e are provided on the cylindrical portions 91a and 91b, respectively, to drive a motor. It is arranged so as to be able to rotate forward and reverse with a force.

Each of the pump wheels 91d and 91e is provided with two shaft holes 91f, one end of which extends in the center direction and the other end extends in the outer circumferential direction.
The rollers 91g supported by the shaft holes 91f can be shifted toward the center or toward the outer periphery in accordance with the rotation directions of the shafts d and 91e. The roller 91g presses the tube 91h between the cylindrical portions 91a and 91b to perform a squeezing action, and a release action that does not pressurize the tube 91h.

In the example shown in FIG. 7, in order to reduce the load on the driving motor, the roller supported by one of the pump wheels performs a pumping action in which the roller is biased in the outer peripheral direction by rotating the motor in one direction. In addition, the rotation of the motor in the other direction causes the rollers supported by the other pump wheel to alternately perform a pumping action in which the rollers are offset in the outer peripheral direction.

One end of each of the tubes 91h is connected to an ink suction port of a capping device for sealing a face plate of a recording head, and receives a negative pressure by driving the pump unit 91 when a cleaning command is received. Is applied to the internal space surrounded by the cap member of the capping device.

On the other hand, the cleaning member drive unit 92
The cleaner cam 92b is loosely fitted to the rotating shaft of the pump wheel 91d via a clutch plate 92a, and the cleaner cam 92b is moved by the compression spring 92c to the clutch plate 92a.
It is configured to be pressed against.

A slide lever 92e having a cleaning member 93 formed thereon is mounted so as to be slidable in the horizontal direction with respect to the frame 92d, and the cleaner cam 92 is mounted on a part of the slide lever 92e.
b is engaged.

The cleaner cam 92b is dragged in the same direction via the clutch plate 92a by one-way rotation of the pump wheel 91d, and acts to move the slide lever 92e in one horizontal direction. The cleaner cam 92b is dragged in the other direction via the clutch plate 92a by rotation of the pump wheel 91d in the other direction, and acts to move the slide lever 92e in the other horizontal direction.

Accordingly, the cleaning member 93 mounted on the upper portion of the slide lever 92e is driven by the motor for driving the pump unit 91 to rotate forward and reverse.
The cleaning member 93 acts so as to be able to enter or retreat from the wiping position on the moving path of the recording head.
Is wiped on the nozzle surface of the recording head in a state of intrusion into the wiping position.

[0019]

In the above-described pump unit, the operation and non-operation of the pump function are controlled by rotating the motor for driving the pump forward and backward. A motor drive circuit for controlling the rotation and the reverse rotation is indispensable.

In such a motor driving circuit, it is necessary to connect at least four switching elements (generally, switching transistors) in a so-called bridge connection.
In addition, since each transistor used in the transistor directly receives a drive current of a motor, a large-capacity transistor that can withstand a large collector loss is required, which raises a problem that the cost of the whole product is increased.

In addition, under the condition that the rotation speed of the drive motor is constant, the pump capacity, that is, the suction amount of the pump, is uniquely determined by the arrangement relationship (effective arrangement angle) of the tube with respect to the cylindrical portion.

For this reason, when an attempt is made to use a pump unit designed for a specific printing apparatus for another model, troubles such as bubbling of ink due to excessive suction operation may be caused during a cleaning operation. There is a problem that inconvenience occurs and the versatility for each model is poor.

Further, in the case where the first and second pumps are provided as in the example shown in FIG. 7 and the pump function is alternately operated in the normal rotation and the reverse rotation, complicated power switching is required. A mechanism is required, and the time required for the suction operation sequence accompanying the power switching is lengthened, which imposes unnecessary waiting time on the user.

Further, when three or more pump units are to be provided, there is a problem in that the combination of the pump units is difficult to design and, as a result, the reliability of operation is reduced.

The present invention has been made in view of such circumstances, and is configured so that a drive motor for driving a plurality of pump units can be selectively driven by one-way rotation drive. It is an object of the present invention to provide an ink jet recording apparatus capable of appropriately selecting a suction operation timing of a pump unit with a simple configuration.

[0026]

In order to achieve the above-mentioned object, an ink jet recording apparatus according to the present invention comprises: an ink jet recording head for discharging ink droplets corresponding to print data; An ink jet recording apparatus comprising: a capping means for sealing and sucking ink from a recording head by receiving a negative pressure from a pump unit, wherein the pump unit regulates an outer shape of a tube in an arc shape. A pump frame having a tube support surface, a pump wheel rotated by a driving force from a driving unit, and movable between a first position on the rotation axis side of the pump wheel and a second position away from the rotation axis. A roller supported by a pump wheel so that the position of the roller is selectively set to the first position or the second position. Further selecting means, wherein when the roller is moved to the second position of the pump wheel, the roller is pressed against a tube disposed on the tube supporting surface to deform the tube. .

In this case, the selecting means preferably includes an urging member for urging the roller in the first position direction of the pump wheel, and a second member of the pump wheel which opposes the urging force of the urging member. The roller guide is selectively guided to a position, and a cam mechanism for selecting a mode of guiding or not guiding the roller by the roller guide.

A roller support groove is formed in the pump wheel so as to be inclined with respect to the radial direction from the rotation axis of the wheel, and the roller guided by the roller guide is driven by the rotation of the pump wheel. The second
It is desirable to be configured to be able to hold in position.

Further, it is desirable that the roller guide is arranged at a position avoiding a tube supporting surface for regulating the outer shape of the tube in an arc shape.

In a preferred embodiment, the pump wheel is positioned symmetrically with respect to the rotation axis of the pump wheel.
Two rollers are provided.

In a preferred embodiment, a plurality of the pump units are arranged, and the cam shape of the cam mechanism is adjusted so that the guiding or non-guiding of the rollers by the roller guide of each pump unit is performed at different timings. Is set.

Further, in a preferred embodiment,
The pump wheel is rotatably driven by a driving unit that rotates in one direction, and the cam mechanism is rotatably driven by a driving unit that drives a paper feed roller.

According to the ink jet recording apparatus constructed as described above, the tube pump as a pump unit for applying a negative pressure to the capping means uses the tube press-contact roller supported on the pump wheel by the selection means. It can be selectively changed to a first position on the rotation axis side of the wheel or a second position away from the rotation axis. In particular, by using a cam mechanism as the selection means and appropriately setting the cam shape of the cam mechanism, the operation and non-operation of the tube pump can be appropriately selected.

Therefore, in an ink jet recording apparatus having a plurality of tube pumps, by devising a cam shape corresponding to each of the tube pumps, each of the tube pumps can perform a pump operation at a different timing. Can be set.

[0035]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an ink jet recording apparatus according to the present invention will be described based on an embodiment shown in the drawings.

FIG. 1 shows the overall configuration of an ink jet recording apparatus to which the present invention is applied. In FIG. 1, reference numeral 1 denotes a carriage. The carriage 1 is connected to a part of a timing belt 2, driven by reciprocating rotation of a motor 3, guided by a guide member 4, and moved parallel to a platen 5. Have been. On the surface of the carriage 1 facing the recording paper 6, a recording head 7 for discharging black ink is mounted on the printing area side (left side in FIG. 1), and a recording head 8 for color printing is mounted on the non-printing area side. The recording heads 7 and 8 are configured to perform printing by receiving ink supplied from the black ink cartridge 9 and the color ink cartridge 10 and discharging ink droplets onto the recording paper 6.

A capping device 11 disposed in the non-printing area is a capping device as capping means. The cap member 12 seals the recording head 7 for black ink and the cap member 13 seals the recording head 8 for color ink. Mounted on the same cap holder. And, as described later, they are connected via tubes 15A, 15B to two pump units 14A, 14B, each of which can be driven independently.

On the print area side adjacent to the capping device 11, for example, a rubber cleaning member 17 for wiping the nozzle opening surfaces of the recording heads 7 and 8 mounted on the carriage 1 as the carriage 1 moves. Is arranged.

At the time of head cleaning,
The cleaning members 17 of the recording heads 7 and 8 remove dust and paper dust adhering to the nozzle plate before sucking the ink, and wipe off the ink adhering to the nozzle plate after sucking the ink. You. The cleaning member 17 is configured to be able to enter or retreat from a wiping position on the movement path of the recording heads 7 and 8 by a cleaning member driving unit described later.

FIG. 2 is a perspective view showing an example of the capping device 11. This capping device 11
Is a cap member 12 for sealing one recording head 7.
And a cap member 13 for sealing the other recording head 8 is mounted on the upper slider 21. Since the face plate of the recording head 7 for black ink is slightly smaller than the face plate of the recording head 8 for color ink,
Actually, the cap member 12 is formed to be slightly smaller than the cap member 13, but in FIG.

The upper slider 21 is mounted on a lower slider 24 mounted on the frame 22 via a lever 23 so as to be able to rise with an arc-shaped locus so as to be able to swing. I have. Thereby, the cap members 12 and 13 are configured to be able to abut against the recording heads 7 and 8 from below in parallel.

When the carriage 1 moves directly above the capping device 11, an engaging member (not shown) arranged on the carriage 1 comes into contact with a part of the lower slider 24, and the lower slider 24 is moved via the lever 23. Standing up,
Cap members 12 and 13 mounted on upper slider 21
Are configured so that the recording heads 7 and 8 arranged on the carriage 1 can be sealed.

The cap members 12 and 13 are formed in such a size that the nozzle opening surfaces of the recording heads 7 and 8 can be sealed in one space, respectively.
The internal space surrounded by the ink suction ports 25, 26
Is communicated to. The tubes 15A and 15B of the pump units 14A and 14B, which will be described later, are connected to the ink suction ports 25 and 26, and when a cleaning command is received, a negative pressure is applied by the pump units 14A and 14B as appropriate. The recording heads 7 and 8 are configured to be able to forcibly discharge ink.

On the other hand, one ends of tubes 27A and 27B are connected to the lower bottoms of the cap members 12 and 13, and the other ends of the tubes 27A and 27B are connected to the atmosphere opening ports 29 and 30 of the valve member 28. ing.

When the cap members 12 and 13 are
When the valve member 28 is moved to a position where the valve member 8 can be sealed, a valve body 32 that is constantly urged toward the valve member 28 by a spring 31 and elastically contacts the valve member 28 is disposed in a region where the valve member 28 is located. The open ports 29 and 30 and the valve member 28 form atmospheric release valves V1 and V2.

By adjusting the pump operation of the pump units 14A and 14B and the operation timing of the air release valves V1 and V2, the air is introduced into the internal space surrounded by the cap members 12 and 13 and the ink is sucked. Is configured to be performed.

FIG. 3 is a sectional view showing an embodiment of a pump unit for sucking the internal space surrounded by the cap members 12 and 13. In the printing apparatus shown in FIG. 1, two pump units are mounted, but both have the same configuration. Therefore, one of the pump units 14A in FIG.
Here is an example.

The pump unit 14A is provided with a pump frame 42 formed of a hard synthetic resin having a tube support surface 41 for regulating the outer shape of the tube in an arc shape. The tube support surface 42 is formed such that an arc-shaped circumferential angle θa is approximately 180 degrees, and one end is provided at the ink suction port 2 of the capping device 11.
A tube 15 </ b> A, which is connected to a discharge ink tank (not shown), is connected to the tube support surface 41.

At the center point of the circular arc surrounded and bent by the tube support surface 41, a disk-shaped pump wheel 43 that rotates in the direction of arrow D by a driving force from a pump motor as a driving means described later is disposed. . The pump wheel 43 has two roller support grooves 44A and 44B so as to be symmetrically positioned with respect to the rotation axis 43a of the pump wheel.
Are formed in the roller supporting grooves 44A, 44B.
Supports the shafts 45a, 45b of a pair of rollers 45A, 45B formed in a column shape in a freely rotatable manner.

Then, the respective rollers 45A, 45B
Is tilted radially from the rotation axis of the wheel 43 so that the pump wheel 43 can move between a first position E on the rotation axis 43a side of the pump wheel 43 and a second position F remote from the rotation axis. Each roller support groove 44A, 44B is formed so as to be in a state.

The pump wheel 43 has a rotation axis 4
A pair of notches 46A and 46B are formed with 3a as a symmetrical point, and one ends of U-shaped springs 47A and 47B as urging members are engaged with the notches 46A and 46B, respectively. The other ends of the pair of springs 47A and 47B are formed as small-diameter U-shaped bent portions, which are engaged with the support shafts 45a and 45b of the rollers 45A and 45B, respectively. The pair of springs 47A, 47B are engaged with the projections 48A, 48B disposed on the wheel 43, respectively, and urge the rollers 45A, 45B toward the first position E of the pump wheel 43. Have been.

A part of the pump frame 42 includes a shaft 4
9 is established, and one end of a first arm 50 is rotatably attached to the shaft 49. First arm 50
At the other end, a connector 53 that is in contact with a cam surface 52 of the cam mechanism 51 is attached. The arm 50 is pulled by a coiled spring 54 attached to a part of the pump frame 42, and the joint 53 is configured to be moved up and down along the cam surface 52 by driving the cam mechanism 51. I have.

A second arm 55 is integrally attached to the first arm 50, and a roller guide 56 bent in an arc is attached to the tip of the second arm 55. The roller guide 56 acts so as to advance and retreat within the movement locus of the rollers 45A and 45B via the first arm 50 and the second arm 55 driven by the cam mechanism 51.

The cam surface 52 of the cam mechanism 51
Roller guide 56 depends on the shape (crest portion) of roller 4
In the state of invading the movement locus of 5A, 45B,
The rotation of the pump wheel 43 in the direction of arrow D causes the leading end of the roller guide 56 to abut against the side wall surfaces of the rollers 45A and 45B.
From the first position E on the side of the rotation axis 43a in the direction of the second position F away from the rotation axis.

As a result, the rollers 45A and 45B move to the locus of the second position F against the urging force of the springs 47A and 47B, and press against the tube 15A disposed along the tube support surface 41.

When the rollers 45A and 45B are pressed against the tube 15A in this manner, the friction between the rollers 45A and 45B
5B is held in the second position F, and the tube 1A is deformed while the tube 16A is in the range of the circumferential angle θa.
Roll along 5A. By such an operation, the tube 15A is squeezed by the rollers 45A and 45B, and the tube 15A operates as a tube pump. When the rollers 45A and 45B move out of the range of the circumferential angle θa, the rollers 45A and 45B return to the first position E by the urging forces of the springs 47A and 47B.

On the other hand, depending on the shape (valley portion) of the cam surface 52 in the cam mechanism 51, the roller guide 56
In a state in which it does not enter the movement locus of A, 45B,
The above-described action by the roller guide 56 does not occur, and the rollers 45A and 45B are held at the first position E by the urging forces of the springs 47A and 47B, so that no pump action is exhibited. That is, the operation and non-operation of the pump action of the pump unit 14A are controlled according to the peak or the valley of the cam surface 52 of the cam mechanism 51.

The roller guide 56 is located at a position avoiding the tube support surface 41 which regulates the outer shape of the tube in an arc shape, preferably, as shown in FIG. 3, the tube support surface 41 facing the rotation direction of the pump wheel 43. It is located immediately before. Thus, the rollers 45A and 45B can be guided by the roller guide 56 with a light load, and the operation reliability can be improved.

Next, FIG. 4 shows an example of a driving force transmission mechanism in the recording apparatus. The transport roller shaft 61 has a gear 62 at one end, and a paper feed motor 63 as a driving unit.
The paper feed roller shaft 66 is driven from a pinion 64 on the shaft of
It is configured to rotate by engaging with a gear 62 attached to the roller shaft 61 via a gear 68 constituting a clutch mechanism.

The gear 68 constituting the clutch mechanism
Always keeps a position away from the gears 62 and 67 by a spring (not shown) as shown in FIG.
, The gears 62, 67 move in the axial direction.
And the sheet feeding roller shaft 66 is driven.

On the other hand, a shaft 71 for holding a gear 70 is configured to be rotated from a pinion 64 of a paper feed motor 63 via an idler 69, and the shaft 71 has a first shaft.
A clutch 72 and a second clutch 73 are provided.

The first clutch 72 is slidable by a coil spring 72e which is urged in the expanding direction between a clutch disc 72a provided directly with the shaft 71 and having a sliding piece 72b and an end board 72d. It is constituted by a driven clutch disc 72c which is driven by being brought into contact with 72b. The driven clutch board 72c constitutes a drive unit for a wiping member described later.

On the other hand, the second clutch 73 is directly connected to the shaft 71 and has a clutch disc 73a provided with a sliding piece 73b,
Coil spring 73e urged in the expanding direction with respect to 3d
, And is constituted by a driven clutch board 73c which is driven by being brought into contact with the sliding piece 73b. The driven clutch disc 73c has a first cam 51 constituting a cam mechanism.
A and the second cam 51B are connected.

In the example shown in FIG. 4, a drive system for driving the two pump units 14A and 14B is shown, and the first arms 50A and 50B for controlling the position of the roller guide 56 of each pump unit are provided. First cam 5
The position is controlled by the 1A and the second cam 51B, respectively.

Then, the two pump units 14A,
14B is configured to be rotationally driven by a shaft 78 that holds a gear 77 from a pinion 75 of a pump motor 74 as a driving unit that is rotationally driven in one direction, via an idler 76. Accordingly, each pump wheel 43 provided in each of the two pump units 14A and 14B is driven to rotate in the direction of arrow D shown in FIG.

FIG. 5 shows a drive unit of the wiping member driven by the drive mechanism shown in FIG.
1 shows the configuration of FIG.

The drive unit 81 for the wiping member is shown in FIG.
Driven clutch board 72c of the first clutch 72 described in
It is configured to be driven by. That is, a rotating arm 81a is attached to the clutch board 72c integrally with the clutch board 72c.
The driving pin provided on the slide plate 81b is loosely fitted into a slot formed in the slide plate 81b, and the slide plate 81b is slid in the horizontal direction by driving the rotation arm 81a.

The cleaning member 17 is mounted on the upper portion of the slide plate 81b. Therefore, the cleaning member 17 is rotated by the paper feed motor 63 in one direction via the first clutch 72 as shown by a broken line in FIG. To the wiping position on the moving path of the recording head. In this state, the nozzle surface of the recording head is wiped.

By the rotation of the paper feed motor 63 in the other direction, the state shown by the solid line in FIG. 5 is dragged from the state shown by the broken line to the state shown by the broken line in FIG.

The cam mechanisms 51A and 51B are rotated via the second clutch 73 as described above, and the cam mechanisms 51A and 51B shown in FIG. It is rotationally driven as shown in FIG.

The arms 50A and 50B driven by the cam mechanisms 51A and 51B respectively connect the roller guides 56 of the tube pumps 14A and 14B to the rollers 45.
A and 45B are made to move back and forth within the movement locus. Therefore, the tube pumps 14A and 14B are
The pump action is performed at the peaks of 1A and 51B, and the pump action is stopped at the valleys of the cam mechanisms 51A and 51B.

In the embodiment shown in FIG. 5, the cam mechanism 51B has a locking lever 82 projecting therefrom.
Starting from the position shown by the broken line in FIG.
In the state shown in FIG. 5D where θ reaches θ4, the rotation of the cam mechanisms 51A and 51B is stopped by contacting the stopper pin 83.

In the embodiment shown in FIG. 5, the operations of the pump units 14A and 14B are stopped from the starting point to the angle θ1 shown in FIG. 5A, and only the pump 14A is driven at the angle θ2. Then, only the pump 14B is driven at an angle of θ3, and the pumps 14A and 14B are driven at an angle of θ4.

FIG. 6 shows an example of the load applied to the pump motor 74 as the driving means during the operation of the pump units 14A and 14B. This example shows a case where the rotation phases of the pair of rollers in the first and second pump units 14A and 14B are set to be 90 degrees with each other.

That is, the load characteristic of one roller 45A in the first pump unit 14A is shown as roller A1, and the load characteristic of the other roller 45B is shown as roller A2. Similarly, the second pump unit 1
In FIG. 4b, the load characteristic of one roller 45A is shown as a roller B1, and the load characteristic of the other roller 45B is shown as a roller B2.

As shown in FIG. 6 (a), in the first pump unit 14A, a state occurs in which the loads slightly overlap at points where the rotation angles of the pump wheel 43 are 0 ° and 180 °. In addition, as shown in FIG. 6B, in the second pump unit 14B, there occurs a state where the loads slightly overlap at points where the rotation angles of the pump wheel 43 are 90 degrees and 270 degrees. Therefore, when the two pump units are driven under the above-described conditions, the combined load characteristics are as shown in FIG. 6C, and the two pumps can be driven stably by designing in consideration of the load of ΔP. Becomes

Note that the form of the two cam mechanisms shown in FIG. 5 is merely an example, and it is a matter of course that the present invention is not limited to such a specific configuration.

In the above-described embodiment, the recording apparatus is provided with two pump units.
For example, in a case where three or more pump units are provided, the present invention can be used more advantageously.

That is, the peak of the load due to the plurality of pump units can be reduced by setting the peaks of the cam mechanisms arranged in each of the plurality of pump units so as not to conflict with each other. With this setting, each pump unit can be reliably driven with a low torque, and a highly reliable recording apparatus can be provided while using a smaller pump motor.

[0080]

As is apparent from the above description, according to the ink jet recording apparatus of the present invention, the moving path of the tube pressure contact roller disposed on the pump wheel can be changed by the selection means. Operation or non-operation mode can be easily changed by setting the selection means.

In particular, when a cam mechanism is used as the selection means, mode selection can be realized by selecting a cam shape, and highly reliable operation can be ensured by a simple configuration.

Further, even when a plurality of pump units are driven by one motor, the peak of the load can be appropriately suppressed by selecting the respective cam shapes, and a small motor having a relatively low torque is used. This can contribute to cost reduction and size reduction of the device.

As compared with the conventional pump unit, each pump can be selectively operated by a pump motor that rotates in one direction.
The device can be realized by a mechanically and electrically simple drive system.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration of an ink jet recording apparatus to which the present invention is applied.

FIG. 2 is a perspective view showing a configuration of a capping unit provided in the recording apparatus shown in FIG.

FIG. 3 is a cross-sectional view showing a configuration of a pump unit mounted on the recording apparatus shown in FIG.

FIG. 4 is a plan view showing an example of a driving force transmission mechanism of the recording apparatus shown in FIG.

5 is an operation timing chart for explaining the operation of the wiping member drive unit and the cam mechanism driven by the drive force transmission mechanism shown in FIG. 4;

FIG. 6 is a load timing chart showing load characteristics of the pump unit shown in FIG. 3;

FIG. 7 is a perspective view showing a configuration of a conventional pump unit and a wiping member drive unit.

[Description of Signs] 1 Carriage 6 Recording paper 7, 8 Recording head 11 Capping device 12, 13 Cap member 14A, 14B Pump unit 15A, 15B Tube 17 Cleaning member 41 Tube support surface 42 Pump frame 43 Pump wheel 44A, 44B Roller support Grooves 45A, 45B Rollers 47A, 47B Spring (biasing member) 50, 50A, 50B First arm 51, 51A, 51B Cam mechanism (selection means) 55 Second arm 56 Roller guide 61 Transport roller shaft 63 Paper feed motor (drive) Means) 66 Paper feed roller shaft 72 First clutch 73 Second clutch 74 Pump motor (driving means) 81 Driving unit of wiping member E First position F Second position

Claims (7)

[Claims] 1. An ink jet recording head for discharging ink droplets corresponding to print data, and a capping means for sealing the recording head and sucking ink from the recording head by receiving a negative pressure from a pump unit. An ink jet recording apparatus comprising: the pump unit, a pump frame having a tube support surface that regulates the outer shape of the tube in an arc shape, a pump wheel that is rotated by a driving force from a driving unit,
A roller supported by the pump wheel so as to be movable between a first position on the rotation axis side of the pump wheel and a second position away from the rotation axis; Or a selecting means for selectively changing the position to the second position. In a state where the roller is moved to the second position of the pump wheel, the roller is pressed against a tube disposed on the tube support surface to press the roller. An ink jet recording apparatus, wherein the recording apparatus is configured to deform a tube. 2. The apparatus according to claim 1, wherein said selecting means includes an urging member for urging said roller in a first position direction of said pump wheel, and moving said roller to a second position of said pump wheel against the urging force of said urging member. 2. The ink jet recording apparatus according to claim 1, comprising a roller guide for selectively guiding and a cam mechanism for selecting a mode of guiding or not guiding the roller by the roller guide. 3. A roller support groove is formed in the pump wheel so as to be inclined with respect to a radial direction from a rotation axis of the wheel, and a roller guided by the roller guide is rotated by rotation of the pump wheel. The ink jet recording apparatus according to claim 1, wherein the ink jet recording apparatus is configured to be held at the second position. 4. The ink jet recording apparatus according to claim 2, wherein the roller guide is arranged at a position avoiding a tube supporting surface for regulating the outer shape of the tube in an arc shape. 5. The ink jet recording apparatus according to claim 1, wherein two rollers are provided so as to be located symmetrically with respect to the rotation axis of the pump wheel. 6. A plurality of said pump units are arranged,
6. The cam shape of the cam mechanism according to claim 2, wherein the guiding of the rollers by the roller guide of each pump unit or the non-guiding is performed at different timings. Ink jet recording device. 7. The apparatus according to claim 7, wherein said pump wheel is rotatably driven by a driving means which rotates in one direction, and said cam mechanism is rotatably driven by a driving means which drives a paper feed roller. An ink jet recording apparatus according to any one of claims 2 to 6.