JP2001063094A - Ink-jet printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate generation of a waste ink by detaching a cap member in a short time at the time of sucking by providing a one-way valve between a sucking cap and a suction pump. SOLUTION: A one-way valve 40 is provided in a tube connecting a cap member (sucking cap) 2 and a suction pump. In the case where the inside of the tube reaches a predetermined negative pressure by driving the suction pump, a spherical valve 650 moves downward, resisting the force of a pressure spring 655 so as to keep a valve open. As a result, a space part of the cap member 2 keep communication with the tube via through holes 640, 285 so that an ink in a nozzle is ejected as a waste ink by the negative pressure in the space part. Thereafter, the negative pressure in the tube is reduced with stop of the suction pump so as to reach a predetermined negative pressure, the spherical valve 650 closes the through holes by the force of the pressure spring 655. In this case, the time for detachment of the cap member 2 from a head after stoppage of the suction pump drive is substantially negligible.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet printer, and more particularly, to an ink jet printer characterized by a structure for removing foreign matter or bubbles in an ink discharge port and an ink supply path connected to the ink discharge port.

[0002]

2. Description of the Related Art An ink storage tank and a print head (hereinafter, simply referred to as a head) so that an ink discharge port has a negative pressure.
And the two are connected by a flexible pipe (hereinafter, referred to as a tube), and the recording paper is moved in a direction perpendicular to the moving direction of the head while the head reciprocates. Accordingly, an on-demand type ink jet printer configured to sequentially perform recording on recording paper is well known.

[0003] In such an ink jet printer, dust or air bubbles may enter the ink discharge port of the head or the ink supply path connected to the ink discharge port due to long-time use. Normal ejection of ink droplets may not be possible.

In some cases, the ink is exposed to the atmosphere for a long time, and only the solvent of the ink evaporates, and the ink discharge port becomes clogged, so that the ink droplet cannot be discharged.

Further, the head surface around the ink discharge port is stained with ink, and this ink solidifies around the discharge port,
As a result, ink ejection may be deteriorated.

Accordingly, unless the ink discharge ports and the ink supply passages are occasionally cleaned by an appropriate method, high-quality image formation cannot be guaranteed.

For this reason, for example, after cleaning the head surface with a cleaning member incorporated in an ink jet printer, or stopping the head at a stop position such as a home position, the ink is forcibly discharged from the ink discharge port. And automatically cleans the inside of the ink supply path.

[0008] For the forced ejection of ink, after the head is positioned at the stop position, the head surface is covered with a sucking cap member, and the sucking cap (hereinafter referred to as a cap member or cap) and a tube are interposed. A configuration is conceivable in which, by operating a suction pump that is connected by a vacuum, the inside of the cap member is set to a negative pressure, the ink in the ink supply path is discharged, and bubbles, dust, and the like in the ink supply path are discharged together with the ink.

[0009]

As described above, the configuration for cleaning the inside of the ink supply path by forcibly discharging the ink has good operability and is extremely useful.

[0010] However, as schematically shown in FIG. 14, the cleaning device in the conventional apparatus is configured such that the cap member 2 that covers the head surface (the surface having the ink discharge ports) 100 of the head 1 and the suction pump P are used. It is merely connected by the tube 150, and the time required from the start of suction for cleaning until the cap member 2 is separated (separated) from the head 1 becomes long.

This is because of the operation of the suction pump P,
The ink discharged from an ink supply path (not shown) fills the volume of the space formed between the head surface 100 and the cap member and the volume of the pipe P, and the pressure near the head surface is equal to the atmospheric pressure. This is due to the long time it takes to become.

FIG. 15 shows the internal pressure (negative pressure) of the cap member at the time of sucking from the start of driving of the suction pump in the above configuration until the cap member can be detached from the head 1.
Indicates a change.

Referring to FIG. 15, another problem in the above configuration is that the ink in the ink supply path starts to be discharged immediately after the operation of the suction pump is started, and the pressure (negative pressure) in the cap member is reduced. Even after the pressure reaches the maximum pressure p1 from the predetermined pressure p2 and returns to the predetermined pressure p2 again due to the pressure drop due to the stoppage of the suction pump, the ink discharge continues until the pressure in the cap member becomes substantially atmospheric pressure. That is, the amount of waste ink is increased more than necessary and wasteful consumption is caused.

In order to solve the above-mentioned problems, it is conceivable to provide a valve for communication and sealing between the cap member and the suction pump. However, drive control for opening and closing is required. However, the configuration becomes complicated.

Further, a small hole is provided in the cap member,
It has been proposed to use a leak valve and reduce the time required to return the pressure.However, if the size of the hole is not accurate, the time required to recover the pressure will vary. Poor sex or handling.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and a main object of the present invention is to provide an ink jet printer which has a simple structure and is capable of detaching a cap member as quickly as possible from the start of suction. It is in.

It is another object of the present invention to provide an ink jet printer configured to minimize wasteful consumption of waste ink during sucking.

[0018]

The above objects of the present invention can be achieved by the following components.

(1) A head including a sucking cap, a suction pump connected to the sucking cap via a tube, and a one-way valve provided between the sucking cap and the suction pump. An ink jet printer comprising a maintenance unit.

(2) a sucking cap, a one-way valve provided integrally with the sucking cap, and a suction pump provided so as to be connected to the sucking cap via the one-way valve and the tube. An ink jet printer comprising a head maintenance unit including a printer.

(3) The one-way valve has a spherical valve having a size capable of closing a through hole formed in the sucking cap, and constantly presses the spherical valve against the through hole. The ink jet printer according to the above (2), wherein a pressing spring is used as a main element.

(4) The one-way valve has a conical valve having a size capable of closing a through hole formed in the sucking cap. The ink jet printer according to the above (2), wherein a pressing spring for pressing is used as a main element.

(5) The one-way valve is provided with a guide rod having a through hole formed in the sucking cap or a packing member capable of substantially closing the periphery thereof, and the guide rod. The packing member is the through hole,
Alternatively, the ink jet printer according to the above (2), characterized in that a pressing spring that constantly presses the periphery thereof is used as a main element.

(6) By operating the suction pump, the negative pressure in the tube is increased to open the one-way valve, and the ink in the nozzles constituting the print head is discharged into the sucking cap covering the print head. After the suction pump is deactivated, the one-way valve is closed due to a decrease in pressure caused by the discharged ink remaining in the tube and the sucking cap, and the sucking cap is detached from the head. An ink jet printer characterized in that it is configured as described above.

(7) By operating the suction pump, the negative pressure in the tube is increased to open the one-way valve, and the ink in the nozzles constituting the print head is discharged into the sucking cap covering the print head. After the suction pump is deactivated, the one-way valve is closed due to a decrease in pressure due to the discharged ink remaining in the tube and the sucking cap, and the sucking cap is detached from the head. An ink jet printer, wherein the suction pump is operated again to discharge the ink accumulated in the tube from the suction pump.

(8) The one-way valve has a spherical valve large enough to close a through hole formed in the sucking cap, and constantly presses the spherical valve against the through hole. The ink jet printer according to the above (6) or (7), wherein a pressing spring is used as a main element.

(9) The one-way valve has a conical valve having a size capable of closing a through hole formed in the sucking cap. The ink jet printer according to (6) or (7), wherein a pressing spring for pressing is a main element.

(10) The one-way valve includes a guide hole having a through hole formed in the sucking cap or a packing member capable of substantially closing the periphery thereof.
The above-mentioned (6) or (7), wherein a main spring is a pressing spring that constantly presses the packing member against the through hole or the periphery thereof through the guide rod. Inkjet printer.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings, but the present invention is not limited to this embodiment.

In the ink jet printer according to the embodiment, a color proof image is recorded by causing ink droplets to fly (discharge) on an image recording surface of a recording sheet in accordance with image data corresponding to color separation dot image data. This is a proof production apparatus.

Therefore, in the description of the present embodiment,
It is referred to as a color proof production device instead of an ink jet printer.

First, the overall structure of a color proof manufacturing apparatus will be described with reference to FIGS.

FIG. 1 is a schematic view of a color proof production apparatus,
FIG. 2 is a view of the head viewed from the ink ejection direction, and FIG. 3 is a schematic perspective view showing the internal structure of the color proof manufacturing apparatus shown in FIG.

In the drawing, the same members as the members (means) shown in FIG. 14 described above are denoted by the same reference symbols.

In FIG. 1, reference numeral 3 denotes a recording sheet S to be described later.
Is a drum having a peripheral surface on which the surface can be fixedly held. In image recording, the drum rotates at a constant speed in a counterclockwise direction as indicated by an arrow.

S is a recording sheet, and its image recording surface has
An ink absorbing layer having a large amount of ink absorbed per unit area is formed.

This is to obtain good tone reproduction from high density to low density.

The surface of the recording sheet S opposite to the image recording surface is a smooth surface.

Reference numeral 5 denotes a sheet cassette for storing a plurality of the recording sheets S. The recording sheets S are stored with the image recording surface facing upward.

Reference numeral 6 denotes a feed roller which comes into contact with the uppermost sheet of the recording sheet S in the above-mentioned stacked state, and sends out the recording sheet S to the left side in the figure according to the recording operation.

When viewed from the moving direction of the recording sheet S, a pair of rollers R1, R provided downstream of the feeding roller 6 is provided.
Reference numeral 2 denotes a conveying roller for conveying the fed recording sheet S toward the drum 3 in cooperation with the guide members G1 and G2, and R3 denotes a pressing roller for pressing the recording sheet S against the drum 3.

Reference numeral 1 denotes a head (print head) provided with an ink discharge port and an ink supply path connected to the ink discharge port, which is located on the rotation center of the drum 3 and, when recording an image, in the width direction of the drum 3 ( (In FIG. 1, front and back sides of the paper)
It is configured to reciprocate.

Specifically, the head 1 is a carriage 1
05, and reciprocate via the carriage 105.

With the above configuration, the recording sheet S stored in the sheet cassette 5 is sent out by the feed roller, is wound and held around the drum, and is moved by the reciprocation of the head 1 and the rotation of the drum 3. In the main and sub scanning,
An image is recorded by the ejected ink droplets according to the image data.

The recording sheet S after image recording is
The sheet is separated from the drum 3 by an appropriate method,
Is discharged onto the discharge tray T through

T1 is a slidable bat constituting the paper discharge tray T, and is in a state where it is pushed in when replacing the sheet cassette 5.

As shown in FIG. 2, the head 1 has a plurality of nozzles 120 each including an ink discharge port and an ink supply path connected to the ink discharge port.
13, 115 and 117.

The nozzle 120 can be said to be a main element constituting the head.

The head mounting areas 110, 113, 11
5, 117, the nozzle head 121 having the above configuration,
122, 123, 124, 125, 126, 127, 1
28 are provided two each.

In the above configuration, the ink discharge port and the ink supply path are formed by processing a single member, but the ink discharge port is formed on the front surface of the member on which the ink supply path is formed. For example, a nozzle may be formed by bonding a water-repellent resin thin plate.

Reference numeral 100 denotes a head surface, and the ink discharge ports are on the same surface.

As shown in FIG. 3, the direct moving means for reciprocating the head 1 having the above-described structure includes a pulley 155 fixed to the shaft of the motor M and a distance from the pulley 155. An endless belt (hereinafter simply referred to as a belt) B stretched between pulleys 160 rotatably supported by a fixing member of the apparatus.

In FIG. 3, the same members as those described above (means) are denoted by the same reference symbols.

That is, the carriage 10 is attached to the belt B.
5 is fixed, and the head 1 is reciprocated in the width direction of the drum 3 via a reciprocating portion of the belt B accompanying the reversible rotation of the motor M.

The belt B is stretched over at least one end of the drum 3.

This is because the head 1 during non-image recording is positioned in an area deviating from the moving area for image recording, that is, at a position outside the end of the drum 3 (for convenience, referred to as a home position). In this position, the head 1 undergoes maintenance for maintaining its function.

The maintenance of the head will be described later.

Reference numeral 200 denotes a guide provided in parallel with the peripheral surface of the drum 3 similarly to the belt B.
The cross section is formed into a polygon (in the embodiment, the cross section is rectangular) so as to fit with the end of the head 05 opposite to the head support side and to have a function of preventing the head 1 from rotating.

In other words, the attitude of the head 1 is determined by the carriage holding portion by the belt B and the guide 200.
And is kept stable through the engagement with the carriage.

Reference numerals 211 to 218 denote ink containers which are provided so as to correspond to the nozzle heads 121 to 128, respectively.
The ink container and the nozzle head are connected so as to be able to supply ink via flexible pipes (tubes) 250 and 255.

In the embodiment, the pipe 250,
255 passes through a tractor unit 260, one end of which is fixed to the carriage 105.

Reference numeral 30 denotes a head maintenance unit (hereinafter, referred to as a maintenance unit), which has a relationship in which the head 1 which is moved to the home position after the image recording is completed can be opposed to the head position. Have a plurality of means.

As shown in FIG. 4, the maintenance unit 30 is configured to be movable via guides 305 and 310 in a direction orthogonal to the reciprocating direction of the head 1.

The maintenance unit 30 includes a first stage 320 fitted with the guides 305 and 310,
A second stage that can move integrally with the first stage and that can move at a predetermined position in a vertical direction perpendicular to the movement in the guide direction;

Reference numerals 340, 350, and 360 denote a capping unit (capping unit), a sucking unit (sucking unit), and a cleaning unit (cleaning unit) fixedly provided on the second stage.

The capping section 340 is connected to the head 1
A sucking cap for forcibly discharging ink in an ink supply path connected to the ink discharge port of the nozzle 120. The sucking cap 350 has a member for closing an opening end (meaning of an ink discharge port) of the nozzle 120. The cleaning unit 360 includes a member, a one-way valve, and the like.
00 is provided with a cleaning member.

The capping unit 340 and the cleaning unit 360 can use a known configuration, and the details are omitted because the configuration is not a feature of the present invention.

Further, the sucking portion 350 according to the present invention is provided.
Although the main part of this will be described later, the sucking part (sucking means) in the figure includes a cap member similar to the cap member 2 for the sucking shown in FIG.

As described above, the maintenance unit 30 in this embodiment can be said to have three means or units, but hereinafter, the maintenance unit 30 relating to the ejection of ink by suction directly related to the present invention will be described. In other words, only a configuration having a cap, a suction pump, a tube connecting the both, and a one-way valve provided between the cap and the suction pump as a main element is referred to as a maintenance unit, and its configuration Will be described later.

It is to be noted that an appropriate structure using a known technique such as a combination of a cam follower and a cam can be easily considered for the raising and lowering mechanism (structure) of the second stage 330.

The operation at the time of maintenance of the color proof manufacturing apparatus having the above configuration will be described.

First, the head 1 is moved to a position above the moving surface of the maintenance unit 30 and stopped.

Next, the first stage 320
05 and 310, the capping unit 34 is moved in the direction of the arrow shown in the figure, for example, in the lower right direction.
0, one of the sucking unit 350 and the cleaning unit 360 is positioned below the nozzle of the head 1.

Thereafter, the second stage 330 is raised, and the intended maintenance is performed.

For example, maintenance by the sucking section 350 (forcible ink discharge processing by suction, hereinafter referred to as ink discharge processing) is performed.

FIGS. 5 to 9 show steps from the start of the ink discharge process to the discharge of the discharged ink (hereinafter referred to as waste ink) into the waste ink container 50. FIG. 6 shows that the head 1 and the cap member 2 are located at positions facing each other in the home position. FIG. 6 shows that the cap member is brought into contact with the head surface 100 of the head 1 so as to cover all the nozzles, and the suction pump P is operated. 7 shows a state in which the suction pump P is stopped after a lapse of a predetermined time, and FIG. 8 shows a state in which the cap member is attached to the head after a lapse of a predetermined time after the operation of the suction pump is stopped. FIG. 9 is a view showing a state in which the suction pump is restarted to discharge waste ink accumulated in the tube.

In the figures, the same means as the above-mentioned means (members) are denoted by the same reference numerals, and redundant description will be omitted.

In the figure, a one-way valve 40 is provided between the tube connecting the cap member 2 and the suction pump P.

The one-way valve 40 is also referred to as a constant-pressure backflow prevention one-way valve, and automatically opens the passage only when the fluid pressure in the tube 150 is equal to or higher than a predetermined pressure (negative pressure).
It functions to allow the fluid to flow in one predetermined direction.

If the reduction is reduced, a normal valve or valve for performing communication and sealing requires drive control for opening and closing the passage. However, the one-way valve according to the present invention is required for such drive control. Since the above means is not required, it contributes to simplification of the configuration and downsizing of the device.

Reference numeral 211 denotes a representative example of the above-described ink container, which is related to the head 1 so as to maintain the ink at a negative pressure at the ink discharge port of the nozzle 120.

FIG. 10 schematically shows a change in pressure (negative pressure) in the cap member 2 corresponding to FIGS.
It is.

In FIG. 10, the horizontal axis represents time (t), and the vertical axis represents negative pressure (p).

In the drawing, t1 is the time when the operation of the suction pump P is started, t2 is the time when the operation (opening) of the one-way valve 40 is started, and t3 is the time.
Denotes a time point at which the operation of the suction pump P is stopped, t4 denotes a time point at which the opening of the one-way valve 40 ends, t5 denotes a time point at which the cap can be separated (separated), and p1 denotes a negative pressure (maximum time) in the cap at the time of sucking. , P2 indicate the operating point pressure at which the one-way valve 40 turns on and off.

The scale at each time point on the time axis in FIG. 10 is shown in association with the scale in FIG.

As will be understood, the suction pump P
Is started, the one-way valve 40 is
The one-way valve 40 is kept closed until the negative pressure in the tube 150 reaches a predetermined negative pressure.

At t2, that is, when the negative pressure in the tube 150 reaches a predetermined negative pressure, the one-way valve 40 fully opens its passage, and the waste ink discharged from the nozzle is It flows through the tube 150 on the suction pump side via a valve, and a part is discharged toward the waste ink container 50.

Further, the negative pressure in the cap member 2, in other words, in the predetermined volume (space) formed by the head surface 100 and the cap member 2 reaches the maximum pressure p 1, and at the time t 3 during that time, the suction pump P Is deactivated, the negative pressure p
1 becomes the negative pressure p2 again, and the one-way valve 40 closes at t4.

The negative pressure in the cap member 2 based on the closing operation of the one-way valve 40 instantaneously returns to a pressure close to the atmospheric pressure at time t5, and almost simultaneously, the ink discharge from the nozzles is stopped. Since the operation is stopped, an unnecessary amount of waste ink is not output, and after the operation of the suction pump P is stopped,
The time required until the cap member 2 can be detached from the head 1 can be almost negligibly short.

As described above, as compared with the conventional ink ejection method shown in FIG. 15, the nozzle 120 does not act on the nozzle 120 before the time point t2 and after the time point t5. Discharge can be prevented.

Thereafter, the cap member 2 is separated from the head 1 and the suction pump P is again brought into the operating state, so that the space between the suction pump P and the one-way valve 40 and the one-way valve 40 are changed. The waste ink accumulated between the ink container and the cap member 2 is discharged to the waste ink container 50.

In FIG. 10, a chain line indicates a change in the internal pressure (negative pressure) of the tube 150 between the suction pump P and the one-way valve 40.

FIG. 11 is a sectional view showing an example of a specific configuration around a cap member prepared in the sucking section 350. As shown in FIG.

In the drawing, the sucking portion 350 is provided with a cap member 2 and a support member 60 for supporting the cap member.
The one-way valve 40 is provided in the support member 60.

The cap member 2 is made of rubber and has a rectangular lip portion 28 corresponding to the shape of the head surface 100.
0, and on the opposite side, the support member 60
Has an engaging portion 283 that engages with the protrusion of the second member.

A through-hole 285 is formed substantially at the center of the cap member 2 in the width direction in the figure.

The support member 60 has grooves 610 on the left and right.
620 are provided therein, and press springs 625, 630 for constantly pressing the cap member upward in the figure.
Has been inserted.

The sucking section 350 includes a member for applying a pressing force to the lower end of the pressing spring, but is omitted in the drawing.

Further, the support member 60 has a through hole 640 and a two-stage hole 643 having a diameter larger than the diameter of the through hole and extending in the same direction so as to be aligned with the through hole 285. Has been drilled.

In the upper hole of the hole 643, a spherical valve 650 that contacts the lower end of the through hole 640 and performs the function of opening and closing the through hole, and the spherical valve is directed toward the through hole 640. A pressing spring 655 for constantly pressing is provided.

A screw is cut on the wall surface forming the lower hole of the hole 643, and the screw portion of the joint J is screwed.

The head of the joint J applies a pressing force for pressing the spherical valve 650 via the pressing spring 655.

Further, a through hole 660 for guiding the waste ink discharged from the nozzle to the tube 150 is provided at the center of the joint J.

The tube 150 is connected to the joint J
Is fitted around the pipe.

In the above configuration, the diameters of the various through holes or the pressing force of the pressing spring can be appropriately determined according to the specifications.

The number of the one-way valves 40 corresponds to the longitudinal direction of the support member 60 (the direction of the front and back of the paper) and corresponds to the center of the head mounting areas 110, 113, 115 and 117. In addition, the arrangement location and the like, including the number thereof, may be changed to other forms so as to satisfy a predetermined function.

For example, a maintenance unit including a cap member including the one-way valve, a suction pump, and the like,
A number corresponding to the eight nozzle heads having the configuration shown in FIG. 2 may be prepared.

With this configuration, the ink discharge processing can be performed with higher accuracy.

Further, as long as the technical idea of the present invention can be achieved, the head mounting area and the shape of the cap member are also free, and the present invention is not limited to the above-described embodiment.

FIG. 12 is a sectional view showing a second embodiment around the cap member prepared in the sucking section 350. As shown in FIG.

In the figure, means having the same function as the means (members) shown in the first embodiment (FIG. 11) are denoted by the same reference symbols except for the valve.

Since the basic configuration is the same as that of the first embodiment, only different portions will be described below.

In the present embodiment, reference numeral 651 denotes a conical valve which has a through hole 6 like the spherical valve (FIG. 11).
Open and close 40.

The conical valve 651 integrally has a guide rod 653 extending below the conical valve and having a lower end part movably positioned in a through hole 660 provided in the joint J.

The pressing spring 65 with the guide rod inserted therein is provided between the jaw of the conical valve 651 and the head of the joint J, and around the guide rod 653.
5 is arranged.

FIG. 13 shows a third embodiment around a cap member integrally having a one-way valve, similarly to the above two embodiments.
It is sectional drawing which shows the form.

In this embodiment, the valve includes a flange 652 and a guide 656 integrally provided above the flange.
And a guide rod (no reference symbol) including a central portion around which the pressing spring 655 is disposed, and a guide portion 658 formed below the pressing spring 655, and an appropriate method such as sticking to the upper surface of the flange portion 652. The fixed packing member 654 is configured as a main element.

A space portion of the cap member 2 (formed by the lip portion 280 and the head surface in the state of the ink discharge processing in which the cap member is in contact with the head surface of the head) through the lower end of the through hole 640. The function of achieving communication (connection) between the space 150 and the tube 150 and sealing the communication state is always directly urged upward via the pressing spring 655. Collar 65
2, and the through hole 640 provided on the upper surface thereof.
And the packing member 654 press-fitted around the lower end portion of the wall surface forming the.

The operation at the time of the ink discharging process using the sucking section 350 having the above configuration is as follows.

When the negative pressure in the tube reaches a predetermined negative pressure by the operation of the suction pump connected via the tube 150, a means for performing a valve function against the urging force of the pressing spring 655 (the spherical valve) , A conical valve, and a guide rod) move downward from the illustrated position, and the valve is opened.

As a result, the space of the cap member 2 communicates with the tube via the through holes 640 and 285, and the ink in the nozzle is discharged as waste ink due to the negative pressure in the space.

Thereafter, when the operation of the suction pump is stopped, the negative pressure in the tube 150 decreases, and when a predetermined negative pressure is reached,
A means for performing a valve function by the urging force of the pressing spring 655 closes the through hole 640.

The above is a valve (synonymous with a one-way valve)
Is provided integrally with the cap member, but needless to say, it may be provided separately as shown in FIGS.

[0124]

According to the simple structure of providing a one-way valve,
It is possible to discharge waste ink without waste.

Further, the processing time for discharging the waste ink can be shortened.

[Brief description of the drawings]

FIG. 1 is a schematic view of a color proof production apparatus.

FIG. 2 is a diagram of the head viewed from an ink ejection direction.

FIG. 3 is a schematic perspective view showing an internal structure of the color proof manufacturing apparatus shown in FIG.

FIG. 4 is a diagram showing a configuration including a moving direction of a maintenance unit.

FIG. 5 is a diagram showing that a head and a cap member are at positions facing each other at a home position.

FIG. 6 is a view showing a state in which the cap member is brought into contact with the head surface of the head so as to cover all the nozzles, and the suction pump P is operated (sucking is started).

FIG. 7 is a diagram showing a state where the suction pump is stopped after a predetermined time has elapsed.

FIG. 8 is a view showing a state in which the cap member is separated (separated) from the head after a predetermined time has elapsed after the operation of the suction pump is stopped.

FIG. 9 is a view showing a state in which the suction pump is restarted to discharge waste ink accumulated in the tube.

FIG. 10 is a diagram schematically showing a change in pressure (negative pressure) in the cap member corresponding to FIGS. 6 to 8;

FIG. 11 is a sectional view showing a specific configuration around a cap member.

FIG. 12 is a cross-sectional view showing a second embodiment around a cap member.

FIG. 13 is a cross-sectional view showing a third embodiment around a cap member.

FIG. 14 is a schematic diagram showing a configuration for cleaning in a conventional apparatus.

FIG. 15 is a diagram showing a change in cap member internal pressure (negative pressure) during sucking from the start of driving of the suction pump in the conventional apparatus to the time when the cap member can be detached from the head.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 head 2 sucking cap 3 drum 5 sheet cassette 30 head maintenance unit 40 one-way valve 50 waste ink container 60 support member 100 head surface 110, 113, 115, 117 head mounting area 120 nozzle 121 to 128 nozzle head 150 tube 211 218 Ink container 280 Lip portion 283 Engagement portion 285,640 Through hole 610,620 Groove 625,630,655 Press spring 643 Hole 650 Spherical valve 651 Conical valve 652 Flange 654 Packing member P Suction pump S Recording sheet

Claims (10)

[Claims] 1. A head maintenance comprising: a sucking cap; a suction pump connected to the sucking cap via a tube; and a one-way valve provided between the sucking cap and the suction pump. An ink jet printer comprising: a unit. 2. A sucking cap, a one-way valve provided integrally with the sucking cap, a suction pump provided so as to be connected to the sucking cap via the one-way valve and a tube, An ink jet printer comprising: a head maintenance unit including: 3. The one-way valve according to claim 1, wherein the one-way valve has a spherical valve having a size capable of closing a through hole formed in the sucking cap;
3. The ink jet printer according to claim 2, wherein a pressing spring that constantly presses is used as a main element. 4. The one-way valve has a conical valve having a size capable of closing a through hole formed in the sucking cap, and constantly presses the conical valve against the through hole. 3. The ink jet printer according to claim 2, wherein a pressing spring is used as a main element. 5. The one-way valve includes a guide hole having a through hole formed in the sucking cap or a packing member capable of substantially closing the periphery thereof, and the guide rod includes: 3. The ink jet printer according to claim 2, wherein a pressing spring that constantly presses a packing member against the through hole or around the through hole is used as a main element. 6. The operation of the suction pump increases the negative pressure in the tube, opens the one-way valve, and discharges the ink in the nozzles constituting the print head into the sucking cap covering the print head. After the suction pump is deactivated, the one-way valve is closed by a decrease in pressure caused by the discharged ink remaining in the tube and the sucking cap, and the sucking cap is detached from the head. An ink jet printer characterized in that it is configured as follows. 7. The operation of the suction pump increases the negative pressure in the tube, opens the one-way valve, and discharges the ink in the nozzles constituting the print head into the sucking cap covering the print head. After the suction pump is deactivated, the one-way valve is closed by a decrease in pressure caused by the discharged ink remaining in the tube and the sucking cap, and the sucking cap is detached from the head.
After that, the ink stored in the tube is discharged from the suction pump by operating the suction pump again. 8. The one-way valve, comprising: a spherical valve having a size capable of closing a through hole formed in the sucking cap;
The ink jet printer according to claim 6, wherein a pressing spring that constantly presses is used as a main element. 9. The one-way valve has a conical valve having a size capable of closing a through hole formed in the sucking cap, and constantly presses the conical valve against the through hole. The ink-jet printer according to claim 6, wherein a pressing spring is used as a main element. 10. The one-way valve includes a guide rod having a through hole formed in the sucking cap or a packing member capable of substantially closing the periphery thereof, and the guide rod includes: 9. The pressing element according to claim 6, wherein a pressing spring that constantly presses the packing member against the through hole or around the through hole is used as a main element.
An inkjet printer according to item 1.