JP2003269627A - Valve mechanism and ink jet type recorder equipped therewith - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a small and lightweight valve mechanism with simple structure. <P>SOLUTION: The valve mechanism is equipped with a flexible tube 21 for feeding fluid, a movable moving body 22 which is arranged so that at least a part of the flexible tube 21 is opposed to the external surface of the tube, and at least the part of the tube is formed with magnetic material, and an electromagnet 24 which is arranged opposite to the part formed with magnetic material of the moving body 22 placing the flexible tube 21 in between. Electromagnetic attraction force is applied to a portion formed with magnetic material of the moving body 22 by magnetic force of the electromagnet 24 and the flexible tube 21 is crushed with the moving body 22 by drawing the moving body 22 to the direction of the electromagnet 24 and the flow passage in the flexible tube 21 is blocked up. <P>COPYRIGHT: (C)2003,JPO

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 for ejecting ink droplets from a plurality of nozzle openings formed in an ink jet recording head toward a recording medium for recording, and a valve mechanism suitable for the same.

[0002]

2. Description of the Related Art Ink jet recording apparatuses have been used for many types of printing, including color printing, because of their relatively low noise during printing and the ability to form small dots with high density.

Such an ink jet recording apparatus is
Generally, an inkjet type recording head mounted on a carriage and reciprocating in a width direction (head scanning direction) of a recording medium such as recording paper, and a recording medium is moved in a direction (medium feeding direction) orthogonal to the head scanning direction. And a feeding means.

In this ink jet recording apparatus, printing is performed by ejecting ink droplets from a recording head onto a recording medium in accordance with print data. Then, by making the recording head mounted on the carriage capable of ejecting ink of each color of black, yellow, cyan, and magenta, not only the text printing by the black ink but also the ejection ratio of each ink can be performed. By changing it, full color printing is possible.

In the above-mentioned recording head, since the ink pressurized in the pressure chamber is ejected from the nozzle as an ink droplet onto the recording medium to perform printing, for example, the increase in the ink viscosity due to the evaporation of the solvent from the nozzle opening, , Due to solidification of ink, adhesion of dust, mixing of air bubbles, etc.
There is a problem of printing failure.

Therefore, when the nozzle opening of the recording head is clogged, or when the ink cartridge is replaced, the nozzle forming surface of the recording head is sealed by the capping means and a negative pressure from the suction pump is applied. The ink is sucked and discharged from the nozzle opening by using the ink jet type, and the function to perform the cleaning operation to eliminate the clogging due to the solidification of the ink in the nozzle opening and the ink discharge failure due to the inclusion of bubbles in the ink flow path is generally used. It is provided in the recording device.

When performing this cleaning operation, it is effective to generate a flow of ink as fast as possible in the ink flow path from the ink cartridge to the nozzle opening of the recording head, which increases the viscosity. Bubbles existing in the flow path can be discharged together with the ink.

However, it is assumed that due to the increase in the number of head nozzles that will be implemented in the future, the current pump will not be able to sufficiently suck the ink and the flow velocity will not be obtained.
Therefore, in order to increase the ink flow rate during the cleaning operation, it is necessary to increase the capacity of the suction pump in order to obtain a large negative pressure. For this purpose, in addition to the increase in size of the pump, a large motor for driving the pump must be used, which inevitably leads to an increase in cost and an increase in size of the entire apparatus.

Further, since a large amount of ink is discharged from the recording head, the life of the ink cartridge is shortened, which causes a problem that the running cost of the user is increased.

Therefore, a valve unit that can be opened and closed is arranged in the ink flow path from the ink cartridge to the recording head, and during the cleaning operation, the valve unit is closed and a negative pressure is applied to the capping means.
A recording apparatus has been proposed in which the valve unit is opened when the negative pressure in the capping means rises to instantaneously increase the flow velocity of the ink in the recording head (for example, Japanese Patent Application No. 11-131, for example). -101764).

According to this structure, it is possible to relatively easily discharge the solidified or thickened ink in the vicinity of the nozzle opening of the recording head without providing a special suction pump for obtaining a large negative pressure. Conceivable. Then, the suction action from the nozzle opening is instantaneously performed, and as a result, it is considered that the cleaning effect can be obtained with a relatively small amount of discharged ink.

[0012]

However, the valve unit in the conventional proposal has a complicated mechanism,
Moreover, since a large valve such as a solenoid valve is used, the size and weight of the entire valve unit inevitably increase. In particular, in the case of an inkjet recording apparatus capable of ejecting multiple types of ink, if a valve unit is arranged for each ink type and it is attempted to drive them selectively, the mechanism becomes more complicated and the size becomes larger. There was a problem that the weight was increased.

As described above, since the conventionally proposed valve unit is large and heavy, when the valve unit is arranged in the carriage of an ink jet recording apparatus, for example, not only the entire carriage becomes large but also the total weight of the carriage. When the carriage is moved, slippage occurs in the gears of the carriage driving mechanism, which causes a so-called step-out phenomenon in the operation of the carriage.

The present invention has been made in consideration of the above-mentioned circumstances, and an object thereof is to provide a small and lightweight valve mechanism having a simple structure and ink supply to a recording head by the valve mechanism. It is an object of the present invention to provide an inkjet recording device that can open and close a path.

[0015]

In order to solve the above problems, a valve mechanism according to the present invention has a flexible tube for transporting a fluid, and at least a part of the flexible tube faces an outer surface of the flexible tube. And a movable body at least a part of which is formed of a magnetic material, and a portion of the movable body formed of the magnetic material of the movable body with the flexible tube interposed therebetween. The electromagnet, wherein the magnetic force of the electromagnet applies an electromagnetic attraction force to a portion of the moving body formed of the magnetic material to draw the moving body toward the electromagnet, thereby causing the flexible tube to move. And an electromagnet that crushes the flow path in the flexible tube by being crushed by a moving body.

[0016] Further, preferably, a guide portion for slidably supporting the moving body for guiding the forward / backward movement of the moving body with respect to the outer surface of the flexible tube is further provided.

Further, preferably, the entire moving body is formed of the magnetic material.

Further, preferably, the moving body has a pressing body which is pressed against the outer surface of the flexible tube, and a swingable lever to which the pressing body is attached.

Further, preferably, at least a part of the pressing body is arranged so as to face the electromagnet with the flexible tube interposed therebetween and is formed of the magnetic material.

Further, preferably, the pressing body is provided midway in the longitudinal direction of the lever, and is arranged at the tip of the lever so as to face the electromagnet with the flexible tube interposed therebetween. And a member made of the magnetic material is attached.

Preferably, the flexible tube has elasticity, and when the magnetic force of the electromagnet disappears, the flexible tube returns to its original state by its elastic force.

Further, preferably, there is further provided an elastic member for urging the moving body in a direction opposite to the direction in which the moving body is attracted by the magnetic force of the electromagnet.

In the ink jet recording apparatus according to the present invention, any one of the above valve mechanisms and the pressure generating element provided corresponding to the pressure chamber communicating with the nozzle opening cause a pressure fluctuation in the ink in the pressure chamber. An ink jet type recording head for ejecting ink droplets from the nozzle opening, and an ink storing section for storing ink supplied to the recording head, and the flexible tube includes the ink storing section and the recording head. And forming at least a part of an ink supply path communicating with.

Preferably, the ink storage section stores a plurality of types of ink, and the valve mechanism is arranged in each of the plurality of ink supply passages formed for each ink type.

Further, preferably, it is possible to independently switch the open / closed state of each of the plurality of valve mechanisms arranged in the plurality of ink supply passages.

Preferably, the electromagnets are shared by the valve mechanisms arranged in the ink supply paths, so that the open / closed states of the valve mechanisms are all switched at the same time.

Further, preferably, a carriage for scanning in the head scanning direction integrally with the recording head is further provided, and the ink storage section has an ink cartridge detachably mounted on the carriage, and the valve mechanism. Is provided on the carriage.

[0028]

DETAILED DESCRIPTION OF THE INVENTION An ink jet recording apparatus according to an embodiment of the present invention will be described below with reference to the drawings.

In the ink jet recording apparatus according to the present embodiment, the pressure generating element provided corresponding to the pressure chamber communicating with the nozzle opening causes a pressure variation in the ink in the pressure chamber to eject an ink droplet from the nozzle opening. An inkjet recording head is provided. As the pressure generating element, for example, a piezoelectric vibrator can be used.

1 and 2 are perspective views showing a schematic structure of the ink jet recording apparatus according to the present embodiment.
In FIG. 1, reference numeral 1 is a carriage, and the carriage 1 is configured to be reciprocally moved in the axial direction of the platen 5 while being guided by a guide member 4 via a timing belt 3 driven by a carriage motor 2. There is. The platen 5 supports the recording paper 6 (a kind of recording medium) from the back surface thereof and defines the position of the recording paper 6 with respect to the recording head 12.

The carriage 1, the carriage motor 2, the timing belt 3, and the guide member 4 constitute a carriage mechanism for scanning the ink jet recording head 12 together with the carriage 1 in the head scanning direction.

The ink jet recording head 12 is mounted on the side of the carriage 1 facing the recording paper 6. Further, ink cartridges (ink storage portions) 7 and 8 for supplying ink to the recording head 12 are detachably attached to the carriage 1.

A cap member 13 is arranged at a home position (right side in FIG. 1) which is a non-printing area of the ink jet recording apparatus. The cap member 13 has a recording head 12 mounted on the carriage 1 at the home position. When the recording head 12 is moved to, the recording head 12 is pressed against the nozzle forming surface to form a closed space between the nozzle forming surface and the nozzle forming surface. Further, below the cap member 13, a pump unit 10 for applying a negative pressure to the closed space formed by the cap member 13 is arranged.

A wiping means 11 provided with an elastic plate such as rubber is arranged in the vicinity of the printing area side of the cap member 13 so as to be able to advance and retreat in the horizontal direction with respect to the movement trajectory of the recording head 12, for example. When the nozzle 1 reciprocates toward the cap member 13 side, the nozzle forming surface of the recording head 12 can be wiped if necessary.

The ink jet recording apparatus according to this embodiment further includes a medium feeding mechanism for intermittently conveying the recording paper 6 to be printed (recorded) by the recording head 12 in the medium feeding direction orthogonal to the head scanning direction. Is equipped with.

Next, the valve mechanism in the ink jet recording apparatus according to the present embodiment will be explained with reference to FIG.

As shown in FIGS. 3A and 3B, the carriage 1 is provided with a valve mechanism 20, and the valve mechanism 20 includes the ink cartridges 7 and 8 and the recording head 12 (FIG. 1). Has a flexible tube 21 forming at least a part of an ink supply path 25 communicating with each other. The flexible tube 21 has elasticity. A movable body 22 which is wholly or partially made of a magnetic material such as iron is provided so as to face the outer surface of the flexible tube 21. The moving body 22 is slidably inserted in the guide portion 23, and
Reference numeral 3 guides the forward / backward movement of the moving body 22 with respect to the flexible tube 21. An electromagnet 24 is arranged facing the moving body 22 with the flexible tube 21 interposed therebetween.

3 (a) and 3 (b) show the case where the valve mechanism 20 is in the open state.
When closing, the electromagnet 24 is energized to exert a magnetic force on the moving body 22, and the moving body 22 is drawn toward the electromagnet 24 by the electromagnetic attraction force. As a result, the flexible tube 21 is crushed by the tip of the moving body 22 and the ink supply path 25 in the flexible tube 21 is closed, and the flow of ink is blocked.

Next, when the valve mechanism 20 in the closed state is opened again, the electromagnet 24 is de-energized so that the electromagnetic attraction force to the moving body 22 disappears. Then, the flexible tube 21 returns to its original state due to its elasticity. As a result, the ink supply path 25 is opened and ink can flow.

Further, as shown in FIG. 4, the valve mechanism 20
Are arranged corresponding to a plurality of types of ink, that is, black (Bk), cyan (C), magenta (M), and yellow (Y), respectively, and each of the plurality of valve mechanisms 20 is controlled by the control unit 26. The open / closed state of can be switched independently. Therefore, in the ink jet recording apparatus according to the present embodiment, it is possible to perform the selective cleaning targeting only the nozzle openings and the ink supply paths 25 corresponding to the specific ink type.

As a modified example, as shown in FIG. 5, a single electromagnet 24 is shared by a plurality of moving bodies 22 so that all of the plurality of moving bodies 22 can be operated simultaneously. All the open / closed states of the plurality of valve mechanisms 20 may be simultaneously switchable. In this way, the structure of the device can be simplified and the cleaning sequence can be simplified.

As described above, according to the ink jet recording apparatus of the present embodiment, the valve mechanism 20 can be closed by pulling the moving body 22 by the magnetic force of the electromagnet 24, so that the structure is simple and its size is small. In addition, even if a plurality of valve mechanisms 20 are arranged on the carriage 1 so as to correspond to a plurality of types of ink as in the present embodiment, the carriage 1 is prevented from becoming large and heavy. It is possible to

Further, as can be seen from FIG. 3, since the valve mechanism 20 in this embodiment attracts the moving body 22 located outside the flexible tube 21 forming the ink supply path 25 by magnetic force, it moves. It is not necessary to penetrate the member for driving the body 22 into the road wall of the ink supply path 25, and a complicated sealing mechanism for such a road wall penetrating member is unnecessary.

Next, an ink jet type recording apparatus according to another embodiment of the present invention will be described with reference to FIG.
Note that this embodiment is a partial modification of the configuration of the valve mechanism in the above-described embodiment, and in the following, portions different from the above-described embodiment will be described.

As shown in FIG. 6, in the valve mechanism 30 according to the present embodiment, the flexible tube 31 that connects the ink cartridges 7 and 8 and the recording head 12 shown in FIG. A pressing body 32 made of a material and an electromagnet 34 are arranged to face each other. The pressing body 32 is attached to the tip of a pair of swingable levers 37, and the pressing body 32 and the lever 37 constitute a moving body 39. The base end of the lever 37 is pivotally attached to a structure 38 fixed to the carriage 1 (FIG. 1). The lever 37 may be formed of either a magnetic material or a non-magnetic material, but by forming the lever 37 with a magnetic material, the electromagnetic attraction force acting on the moving body 39 by the magnetic force of the electromagnet 34 can be increased.

When the valve mechanism 30 is closed in the present embodiment, in the valve mechanism 30 in the open state shown in FIGS. 6A and 6B, the electromagnet 34 is energized to press the pressing body by the electromagnetic attraction force. By pulling 32 toward the electromagnet 34 side, as shown in FIG.
1 is crushed from the outside to close the ink supply path.
When the valve mechanism 30 is opened, the energization of the electromagnet 34 is cut off to eliminate the electromagnetic attraction force.
The elasticity of the flexible tube 31 itself pushes the pressing body 32 back to open the ink supply path.

Also in this embodiment, the same effect as that of the above-described embodiment can be obtained. FIG. 7 shows a modification of the embodiment shown in FIG. 6, and in this modification, the compression spring 40 for urging the pressing body 32 away from the electromagnet 34 includes the lever 37 and the structure 38. It is provided between.

In the present modification, when the ink supply path is closed, the pressing body 3 is caused by the electromagnetic attraction force of the electromagnet 34.
2 is pulled against the spring force of the compression spring 40. on the other hand,
When the ink supply path is opened, the energization to the electromagnet 34 is cut off to eliminate the electromagnetic attraction force, so that the pressing body 32 is pushed back by the spring force of the compression spring 40 and the elastic force of the flexible tube 31. The ink supply path is opened.
In this modification, the flexible tube 31 having no elasticity may be used.

8 (a) and 8 (b) show another modification of the embodiment shown in FIG. 6, in which the pressing body 32 is not at the tip of the lever 37 but in the middle thereof. It is provided in. Further, at the tip of the lever 37, a member 41 to be attracted, at least a part of which is made of a magnetic material, is provided so as to face the electromagnet 34 with the flexible tube 31 interposed therebetween. In this modification, the pressing body 32 may be formed of either a magnetic material or a non-magnetic material. Pressing body 32, lever 37, and attracted member 41
The moving body 42 is constituted by.

In the present modification, when the ink supply path is closed, the attracted member 4 provided at the tip of the lever 37.
1 is attracted by the electromagnetic attraction force of the electromagnet 34. As a result, the pressing body 32 moves to the flexible tube 31 side and crushes the flexible tube 31. According to this modification, since the pressing body 32 is provided in the middle of the lever 37 and the attracted member 41 at the tip of the lever 37 is attracted by the electromagnetic attraction force, the pressing force of the flexible tube 31 by the pressing body 32 is exerted. Can be increased.

[0051]

As described above, according to the present invention, the valve mechanism can close the flow path in the flexible tube by attracting the moving body by the electromagnetic attraction force of the electromagnet, so that the structure is simple. The size and weight of the carriage are small, and therefore, for example, even when a plurality of valve mechanisms are arranged in the carriage corresponding to each of a plurality of types of ink in an ink jet recording apparatus, the carriage becomes large and heavy. It is possible to suppress.

[Brief description of drawings]

FIG. 1 is a perspective view showing a schematic configuration of an inkjet recording apparatus according to an embodiment of the present invention.

FIG. 2 is another perspective view showing a schematic configuration of an ink jet recording apparatus according to an embodiment of the present invention.

FIG. 3 is an enlarged cross-sectional view of an ink cartridge, a valve mechanism, and its periphery of the ink jet recording apparatus shown in FIGS. 1 and 2, (a) being a side view;
(B) is the figure seen from the front.

FIG. 4 is a block diagram showing a plurality of valve mechanisms and their control units of the inkjet recording apparatus shown in FIGS. 1 and 2.

5 is a block diagram showing a plurality of valve mechanisms and a controller thereof according to a modified example of the ink jet recording apparatus shown in FIG.

FIG. 6 is an enlarged view showing a valve mechanism of an ink jet recording apparatus according to another embodiment of the present invention,
(A) is a side view of an open state, (b) is a front view of an open state, (c) is a side view of a closed state.

7 is a side view showing a valve mechanism according to a modified example of the embodiment shown in FIG.

8A and 8B are views showing a valve mechanism according to another modified example of the embodiment shown in FIG. 6, in which FIG. 8A is a side view and FIG. 8B is a front view.

[Explanation of symbols]

1 carriage 6 Recording paper (recording medium) 12 Inkjet recording head 20,30 valve mechanism 21,31 Flexible tube 22, 39, 42 mobile 23 Guide 24, 34 electromagnets 25 ink supply path 26 Control unit 32 Pressing body 37 lever 38 structure 40 compression spring 41 Member to be attracted

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 2C056 EA14 EA23 EC24 FA10 HA37                       JA13 JC05 JC20 KB04                 3H106 DA07 DA22 DA32 DB22 DB32                       DC14 DC17 DD02 EE03 EE04                       EE34 GA01 GA15 GB08 KK01                       KK31

Claims (13)

[Claims] 1. A flexible tube for transporting a fluid, and a movable mover at least a part of which is arranged to face an outer surface of the flexible tube and at least a part of which is made of a magnetic material. A body and an electromagnet disposed so as to face the portion formed of the magnetic material of the moving body with the flexible tube sandwiched therebetween, wherein the magnetic material of the moving body is formed by the magnetic force of the electromagnet. By applying an electromagnetic attraction force to the formed portion to draw the movable body toward the electromagnet, the flexible tube is crushed by the movable body to close the flow path in the flexible tube. A valve mechanism comprising: an electromagnet. 2. The valve according to claim 1, further comprising a guide portion that slidably supports the moving body to guide the movement of the moving body with respect to the outer surface of the flexible tube. mechanism. 3. The valve mechanism according to claim 1, wherein the entire moving body is made of the magnetic material. 4. The moving body has a pressing body that is pressed against the outer surface of the flexible tube, and a swingable lever to which the pressing body is attached. Valve mechanism. 5. The at least part of the pressing body is arranged so as to face the electromagnet with the flexible tube interposed therebetween and is formed of the magnetic material. The valve mechanism described. 6. The pressing body is provided midway in the longitudinal direction of the lever, and is arranged at the tip of the lever so as to face the electromagnet with the flexible tube interposed therebetween. The valve mechanism according to claim 4, wherein a member made of a magnetic material is attached. 7. The flexible tube has elasticity, and when the magnetic force of the electromagnet disappears, the flexible tube returns to its original state by its elastic force. The valve mechanism according to any one of 6 above. 8. An elastic member for urging the moving body in a direction opposite to a direction in which the moving body is attracted by the magnetic force of the electromagnet.
The valve mechanism according to any one of 1. 9. A valve mechanism according to any one of claims 1 to 8 and a pressure generating element provided corresponding to a pressure chamber communicating with a nozzle opening, thereby causing a pressure fluctuation in ink in the pressure chamber. An ink jet recording head for generating and ejecting an ink droplet from the nozzle opening; and an ink storage section for storing ink to be supplied to the recording head, wherein the flexible tube includes the ink storage section and the ink storage section. An ink jet recording apparatus, characterized in that at least a part of an ink supply path communicating with a recording head is formed. 10. The ink storage section stores a plurality of types of ink, and the valve mechanism is arranged in each of the plurality of ink supply passages formed for each ink type. The inkjet recording apparatus according to claim 9. 11. The ink jet recording apparatus according to claim 10, wherein each of the plurality of valve mechanisms arranged in the plurality of ink supply paths can be independently opened and closed. 12. The valve mechanism arranged in a plurality of the ink supply paths shares the electromagnet so that the open / closed states of all the valve mechanisms can be switched at the same time. Claim 10
The ink jet recording apparatus described. 13. A carriage for scanning in the head scanning direction integrally with the recording head, the ink storage portion having an ink cartridge detachably mounted on the carriage, and the valve mechanism having the carriage. The ink jet recording apparatus according to any one of claims 9 to 12, wherein the ink jet recording apparatus is provided in the.