JP7068645B2 - Manufacturing method of liquid discharge head, liquid discharge device and liquid discharge head - Google Patents

Description

The present invention relates to a liquid discharge head, a device for discharging a liquid, and a method for manufacturing a liquid discharge head.

Conventionally, a plurality of nozzles for discharging liquid, a plurality of individual liquid chambers communicating with each of the plurality of nozzles, and a common liquid chamber communicating with a plurality of individual liquid chambers are provided. A liquid discharge head having an extension is known.

Patent Document 1 describes a liquid discharge head having an extension portion extending to the outside of the head at both ends of a common liquid chamber in the nozzle arrangement direction. One end of the discharge pipe is connected to one expansion portion, and one end of the supply pipe is connected to the other expansion portion. A discharge side on-off valve is attached to the other end of the discharge pipe. The other end of the supply pipe is connected to a head tank that temporarily stores ink. One end of the supply tube is connected to this head tank. A head-side supply joint having an on-off valve (valve) is attached to the other end of the supply tube.

When performing initial filling to fill an empty liquid ejection head with ink, connect the filling side joint attached to the other end of the tube to which one end is connected to the ink bottle of the ink filling unit to the head side supply joint to the head. Open the on-off valve of the side supply fitting. Further, the discharge side joint attached to the other end of the tube whose one end is connected to the waste liquid tank of the ink filling unit is connected to the on-off valve attached to the other end of the discharge pipe to open the on-off valve. Next, the ink in the ink bottle is sent out. The ink discharged from the ink bottle moves in the supply tube and flows into the head tank. Then, it flows from the head tank to the supply pipe and flows into the liquid discharge head. When the liquid ejection head is filled with ink and the ink is discharged into the waste liquid tank, the ink supply is stopped and the initial filling operation is terminated. After the initial filling operation is completed, the on-off valve is closed and the filling side joint is removed from the head side supply joint. Also, after closing the discharge side on-off valve, remove the discharge side joint from the discharge side on-off valve. By closing each on-off valve, each expansion portion is sealed, and it is possible to prevent air from flowing into the liquid discharge head and ink from leaking out after the initial filling.

However, in the apparatus described in Patent Document 1, there is a possibility that the cost of the apparatus may be increased.

In order to solve the above-mentioned problems, the present invention has a plurality of nozzles for discharging a liquid, a plurality of individual liquid chambers each communicating with the plurality of nozzles, and a plurality of individual liquid chambers communicating with the individual liquid chambers. In a liquid discharge head provided with a common supply liquid chamber for supplying the liquid and having expansion portions extending to the outside of the head at both ends in the nozzle arrangement direction of the common supply liquid chamber, at least one of the plurality of expansion portions is A flow path forming means including a connection portion to which parts can be connected and an on-off valve for opening and closing the flow path between the connection portion and the supply common liquid chamber is connected, and the remaining expansion portion is connected. The liquid is immutably sealed so as to flow, and has a circulation common liquid chamber into which the liquid flows from the plurality of individual liquid chambers, and the circulation common liquid chamber has a plurality of circulation common liquid chambers reaching the outside of the head. It has a circulation expansion part, and at least one of the plurality of circulation expansion parts is an on-off valve that opens and closes a connection part to which parts can be connected and a flow path between this connection part and the circulation common liquid chamber. It is characterized in that a flow path forming means provided with the above is connected, and the remaining circulation expansion portion is immutably sealed so as to allow the liquid to flow .

According to the present invention, the cost of the device can be reduced.

The schematic diagram which shows the structure of the liquid flow path of the liquid discharge head of this embodiment. Schematic diagram of a coupling with a sealing function. A cross-sectional view of one individual liquid chamber cut along a direction orthogonal to the nozzle arrangement direction. The schematic diagram which shows an example of the liquid flow path at the time of the initial filling operation. The figure explaining the work after the initial filling. The schematic diagram which shows the conventional liquid discharge head. The schematic diagram which shows the structure of the liquid flow path of the liquid discharge head of a modification. FIG. 3 is a cross-sectional view of a modified liquid discharge head in which one individual liquid chamber is cut along a direction orthogonal to the nozzle arrangement direction. The block diagram which shows an example of an ink circulation system. A block diagram showing another example of an ink circulation system. The plan view of the main part of the apparatus which discharges a liquid which concerns on this embodiment. The side explanatory view of the main part of the apparatus which discharges a liquid which concerns on this embodiment. Explanatory view of the main part of the unit.

FIG. 1 is a schematic view showing a configuration of a liquid flow path of the liquid discharge head 434 of the present embodiment.
The liquid ejection head 434 according to the present embodiment is provided with a plurality of nozzles 31 for ejecting liquid ink, and a plurality of individual liquid chambers 23 corresponding to these nozzles 31. Further, the liquid discharge head 434 has a supply common liquid chamber 12 for supplying ink to each individual liquid chamber.

At one end (right side in the figure) of the nozzle arrangement direction of the common supply liquid chamber 12 (left and right direction in the figure), a first series of communication that extends from the common liquid chamber 12 to the outside of the head and communicates with the outside. A portion 121a is provided, and a second communication portion 121b, which is an expansion portion, is provided at the other end. One end of the first connecting pipe 71 is attached to the first series passage portion 121a, and the second coupling member of the coupling 80 with a sealing function as a connecting portion is attached to the other end of the first connecting pipe 71. 80b is attached. The first coupling member 80a of the coupling 80 with a sealing function is attached to the other end of the supply pipe 74 to which one end is connected to the head tank in which the ink is temporarily stored. In the normal ink ejection operation, the ink of the head tank is supplied to the liquid ejection head 434 via the first series passage portion 121a.

Further, one end of the second connecting pipe 72 is connected to the second communicating portion 121b, and a sealing portion 73 is formed at the other end of the second connecting pipe 72. The sealing portion 73 is formed by being crushed by welding or the like as described later.

FIG. 2 is a schematic view of the coupling 80 with a sealing function.
The coupling 80 with a sealing function has a first coupling member 80a and a second coupling member 80b. Each of the coupling members 80a and 80b is provided with on-off valves 80a2 and 80b2 urged by springs 80a1 and 80b1, respectively. At the time of separation (when not connected), the flow path is sealed with the on-off valves 80a2, 80b2 closed, and at the time of connection, the on-off valves 80a2, 80b2 are pushed down to open each other, and the flow path is opened by pushing down. It is configured. As the coupling 80 with such a sealing function, a commercially available one such as a non-spill coupling made by CPC can be used.

FIG. 3 is a cross-sectional view of one individual liquid chamber 23 cut along a direction orthogonal to the nozzle arrangement direction.
As shown in FIG. 3, in the liquid discharge head 434, a frame 1 in which a common supply liquid chamber 12 is formed, a flow path plate 2 in which a plurality of individual liquid chambers 23 and the like are formed, and a plurality of nozzles 31 are formed. It is provided with a nozzle plate 3 and a diaphragm 6. Further, it includes a laminated piezoelectric element 5 which is a plurality of pressure generating elements provided corresponding to the plurality of individual liquid chambers 23, and a base 4 to which the laminated piezoelectric element 5 is fixed.

The nozzle plate 3 is made of a metal material, for example, a Ni plating film produced by an electroforming method, and forms a large number of nozzles 31 which are fine ejection ports for flying ink droplets. The internal shape (inner shape) of the nozzle 31 is formed in a horn shape (may be a substantially cylindrical shape or a substantially circular pyramidal shape). The diameter of the nozzle 31 is about 20 [μm] to 35 [μm] on the ink droplet outlet side. The nozzle pitch in each row was 150 [dpi].

The ink ejection surface (nozzle surface side) of the nozzle plate 3 is provided with a water-repellent treatment layer that has been subjected to a water-repellent surface treatment. For example, PTFE-Ni eutectoid plating, electrodeposition coating of fluororesin, vapor deposition coating of evaporable fluororesin (for example, fluororesin pitch, etc.), baking after solvent application of silicon-based resin / fluororesin, etc. A water-repellent treatment layer selected according to the physical properties of the ink is provided. As a result, the drop shape and flight characteristics of the ink are stabilized, and high-quality image quality can be obtained.

The flow path plate 2 is provided so as to be laminated on the nozzle plate 3, and in addition to the plurality of individual liquid chambers 23, a plurality of introduction portions for introducing ink from the common supply liquid chamber 12 to the individual liquid chamber 23. 20. It has a concave damper chamber 24 corresponding to the damper 64 of the diaphragm 6. The damper chamber 24 faces the supply common liquid chamber 12 with the damper 64 interposed therebetween. Further, the flow path plate 2 has a supply fluid resistance portion 21 between the individual liquid chamber 23 and the introduction portion 20.

The flow path plate 2 is formed by patterning the individual liquid chamber 23, the introduction portion 20, and the damper chamber 24 by an etching method using a silicon single crystal substrate. Further, the liquid discharge head 434 is provided with a portion for narrowing the etching width, which is used as the supply fluid resistance portion 21.

The diaphragm 6 is provided so as to be laminated on the flow path plate 2, and is supplied with a thin film diaphragm portion 62, an island-shaped convex portion 61 joined to the laminated piezoelectric element 5 formed in the central portion thereof, and a supply. It has an ink inlet 63 that communicates the common liquid chamber 12 and the introduction portion 20, and a thin film damper 64. The thin film diaphragm portion 62, the island-shaped convex portion 61, and the ink inlet 63 are provided in plurality corresponding to the individual liquid chambers 23.

The laminated piezoelectric element 5 is bonded to the island-shaped convex portion 61 via an adhesive layer 7. The laminated piezoelectric element 5 includes a piezoelectric layer of lead zirconate titanate (PZT) having a thickness of 10 [μm] to 50 [μm] / layer and a silver / parajum (AgPd) having a thickness of several [μm / 1 layer]. The internal electrode layers made of the above are alternately laminated. The internal electrode layer is connected to the external electrode at both ends. The laminated piezoelectric element 5 is divided into comb-teeth shapes by a half-cut dicing process, and each one is used as a drive unit and a support unit (non-drive unit). The length of the outside of the external electrode is limited by processing such as a notch so that it is divided by a half-cut dicing process, and these are a plurality of individual electrodes. The other is not divided in the dicing process and is conducting, so that it becomes a common electrode.

An FPC (flexible printed circuit) is solder-bonded to the individual electrodes of the laminated piezoelectric element 5. Further, the common electrode is joined to the Gnd electrode of the FPC by providing an electrode layer at the end of the laminated piezoelectric element 5 and turning it. A head driver, which is a head control unit, is mounted on the FPC to control the application of a drive voltage to the drive unit.

The base 4 to which the laminated piezoelectric element 5 is fixed is made of barium titanate-based ceramic, and the laminated piezoelectric elements 5 are arranged and joined in two rows. Further, the frame 1 in which the common supply liquid chamber 12 is formed is manufactured by resin molding. Further, at both ends of the frame 1 in the nozzle arrangement direction, a first communication portion 121a and a second communication portion 121b formed so as to reach the upper surface which is the outer peripheral surface of the wall of the supply common liquid chamber 12 are also formed. ..

In the liquid discharge head 434 configured in this way, a drive waveform (pulse voltage of 10 [V] to 50 [V]) composed of drive pulses is applied to the laminated piezoelectric element 5 according to the recorded signal. As a result, displacement in the stacking direction occurs in the laminated piezoelectric element 5, the individual liquid chamber 23 is pressurized via the diaphragm 6, the pressure rises, and ink droplets are ejected from the nozzle 31. After that, with the end of ink droplet ejection, the ink pressure in the individual liquid chamber 23 decreases, and a negative pressure is generated in the individual liquid chamber 23 due to the inertia of the ink flow and the discharge process of the drive voltage (drive pulse). Move to the ink filling process. Specifically, the ink in the common supply liquid chamber 12 passes through the supply fluid resistance portion 21 from the common supply liquid chamber 12 through the ink inlet 63, and is filled in the individual liquid chamber 23.

The supply fluid resistance portion 21 is effective in attenuating the residual pressure vibration after discharge, but becomes a resistance against refilling due to surface tension. By appropriately selecting the supply fluid resistance unit 21, the residual pressure attenuation and the refill time can be balanced, and the time (drive cycle) until the next ink droplet ejection operation can be performed can be shortened.

Next, the initial filling operation of filling the liquid ejection head 434 with ink will be described.

FIG. 4 is a schematic diagram showing an example of the liquid flow path during the initial filling operation.
The other end of the first connecting pipe 71 to which the second coupling member 80b of the coupling 80 with a sealing function is attached to one end is connected to the first series passage portion 121a of the liquid discharge head 434. As a result, a flow path forming means provided with a coupling member serving as a connection portion and an on-off valve 80b2 for opening and closing the flow path between the coupling member and the supply common liquid chamber is connected to the first series passage portion 121a. To. Further, one end of the second connecting pipe 72 is connected to the second communicating portion 121b. Next, the other end of the second connecting pipe 72 is connected to the waste liquid tank 82, and the second coupling member 80b is attached to the tip of the supply pipe 83 connected to the ink liquid storage portion 81. Connect to member 80a. The other end of the second connecting pipe 72 is connected to the ink liquid storage unit 81, and the second coupling member 80b is connected to the first coupling member attached to the tip of the pipe connected to the waste liquid tank 82. It may be configured to be used.

Next, the ink in the ink liquid storage unit is flowed by a pump or the like, and the ink is supplied to the supply common liquid chamber 12 via the first series passage unit 121a. Then, the ink flows into the common supply liquid chamber 12 and each individual liquid chamber 23, and the ink is filled in the common supply liquid chamber 12 and each individual liquid chamber 23. Further, the air in the common supply liquid chamber is discharged to the waste liquid tank 82 through the second communication portion 121b and the second connection pipe 72.

When the supply common liquid chamber 12 is filled with the liquid, the ink is discharged from the second communication portion 121b and discharged to the waste liquid tank 82. Then, when the ink is discharged to the waste liquid tank 82, the ink supply to the liquid discharge head 434 is stopped. As a result, it is possible to reliably fill the ink and suppress the residual air in the liquid ejection head. Further, in this example, when the ink is discharged to the waste liquid tank 82, the ink supply to the liquid discharge head 434 is stopped. However, for example, the ink discharged to the waste liquid tank 82 does not contain air and a predetermined amount. The ink supply may be stopped after the ink is discharged.

Further, by providing communication portions at both ends of the common supply liquid chamber 12, supplying ink from the communication portion at one end and discharging ink from the communication portion at the other end, the air in the liquid discharge head 434 is efficiently discharged. This makes it possible to satisfactorily suppress the residual air in the liquid discharge head.

FIG. 5 is a diagram illustrating the work after the initial filling.
The second coupling member 80b is removed from the first coupling member 80a of the ink liquid storage unit 81. Further, the second connecting pipe 72 is deformed and crushed to form an immutable sealing portion 73, and the second connecting pipe 72 is cut from the portion where the sealing portion 73 is formed. do. The sealing portion 73 is preferably formed in the vicinity of the second communication portion 121b. By forming the sealing portion 73 in the vicinity of the second communicating portion 121b, it is possible to prevent the second connecting pipe 72 from becoming an obstacle in the device for discharging the liquid.

When the material of the second connecting pipe 72 is a thermoplastic resin such as a tube, the sealing portion 73 is formed by heat welding, and the second connecting pipe 72 is cut from the portion where the sealing portion 73 is formed. can do. When the second connecting pipe 72 is made of metal or the like, the sealing portion 73 can be formed by crimping. Further, only the portion where the sealing portion 73 of the second connecting pipe 72 is formed may be a metal pipe, and the metal pipe may be crimped to form the sealing portion 73. From the viewpoint of ease of sealing and the like, sealing by heat welding of a thermoplastic resin is preferable to sealing by crimping of a metal.

Further, as the heat welding of the thermoplastic resin, for example, heat may be directly applied to the portion of the second connecting pipe 72 that has been crushed by bending or the like to perform heat welding, or the inner peripheral surface of the crushed portion of the pipe may be heat-welded. You may use ultrasonic welding which is welded by frictional heat by vibrating ultrasonically. Ultrasonic welding has an advantage that welding can be performed in a short time as compared with a method of heat welding by directly applying heat, and welding by ultrasonic welding is preferable.

As a result, the flow path forming means provided with the first connecting pipe 71 and the second coupling member 80b is connected to the first communication portion 121a shown in FIG. 1, and the tip is connected to the second communication portion 121b. A liquid discharge head is manufactured to which a second connecting pipe 72 is formed, in which a sealing portion 73 that is crushed and cannot be changed so that the liquid flows can be formed.

In the liquid discharge head 434 manufactured as described above, the first communication portion 121a is sealed by the second coupling member 80b, and the second communication portion 121b is sealed by the sealing portion 73 of the second connection pipe 72. Since it is stopped, air does not enter from these communication parts. After the liquid discharge head manufactured in this manner is attached to the device for discharging the liquid, the second coupling member 80b is attached to the other end of the pipe whose one end is connected to the head tank. Connect to. As a result, the ink liquid discharged from the nozzle and consumed is replenished from the head tank to the liquid discharge head 434.

FIG. 6 shows a conventional liquid discharge head 434'.
Conventionally, a flow path forming means composed of a connecting pipe and a second coupling member 80b is connected to each of the first communication portion 121a and the second communication portion 121b. Then, the second coupling member 80b of either the first communication portion 121a or the second communication portion 121b is connected to the first coupling member attached to the tip of the tube connected to the ink liquid storage portion 81. The other second coupling member 80b is connected to the first coupling member attached to the tip of the pipe connected to the waste liquid tank 82 to perform the initial filling operation. After the initial filling operation is completed, the liquid ejection head filled with ink can be obtained by removing the second coupling member of the first communication portion 121a and the second communication portion 121b from the first coupling member. Since the first communication portion 121a and the second communication portion 121b are sealed by the second coupling member, air does not enter from the first communication portion 121a and the second communication portion 121b.

However, in the conventional liquid discharge head, since the flow path forming means provided with the coupling member with the sealing function is connected to both the first communication portion 121a and the second communication portion 121b, the cost of the apparatus is increased. There is a problem that leads to. Further, there is also a problem that providing the coupling members with a sealing function on both of them leads to an increase in the size of the device.

On the other hand, in the present embodiment, since the second connecting pipe 72 whose tip is crushed to form the sealing portion 73 is connected to the second communicating portion 121b, the number of parts is increased as compared with the conventional configuration shown in FIG. It is possible to reduce the cost, suppress the cost increase of the device, and suppress the increase in size of the device.

If the second connecting pipe 72 whose tip is crushed to form the sealing portion 73 is connected before the initial filling operation, the air in the liquid discharge head cannot be evacuated well and the air remains in the second connecting pipe 72. Will end up. Further, even when the pipe from which the tip is crushed and the sealing portion 73 is formed is replaced from the second connecting pipe 72 after the initial filling operation, air enters at the time of replacement and air remains in the pipe. As in the present embodiment, after the initial filling operation is completed, the second connecting pipe 72 is crushed to form the sealing portion 73, so that air does not remain in the second connecting pipe 72 and the second connecting pipe 72 is formed. Can be filled with ink. In other words, if the second connecting pipe 72 is filled with ink, it can be determined that the sealing portion 73 is formed after the initial filling.

Further, in the present embodiment, the second connecting pipe 72 is crushed to form an immutable sealing portion so that the liquid can flow, but the second communication portion 121b is crushed so that the liquid flows. An immutable seal may be formed. In this configuration, the second connecting pipe 72 is also unnecessary, and further cost reduction can be achieved. If there is a portion that is convexly expanded from the common liquid chamber, it can be determined that the portion forms a sealing portion that cannot be changed so that the communication portion 121b is crushed and the liquid flows. ..

Further, in the present embodiment, the on-off valve is provided in the coupling member serving as the connecting portion, but the coupling member and the on-off valve may be provided separately. Further, the flow path forming means connected to the first series passage portion 121a may be configured by providing an on-off valve at the tip of the first connecting pipe 71 and providing a connecting pipe as a connecting portion on the on-off valve.

Further, three or more communication portions may be provided. In such a configuration, in the ink ejection operation, the communication portion to which ink is supplied from the head tank has a connection portion to which a component can be connected at the tip, and opens and closes a flow path between the connection portion and the communication portion. A flow path system back means provided with an on-off valve is connected, and the remaining communication portion is sealed so that parts cannot be attached or detached.

Next, a modification will be described.

FIG. 7 is a schematic view showing the configuration of the liquid flow path of the liquid discharge head of the modified example, and FIG. 8 shows the liquid of the modified example in which one individual liquid chamber 23 is cut along a direction orthogonal to the nozzle arrangement direction. It is sectional drawing of the discharge head.
The liquid ejection head of this modification has a circulation common liquid chamber 50 into which ink flows from the individual liquid chamber 23, and the ink flowing into the circulation common liquid chamber 50 is returned to the head tank to circulate the ink. It is an ink circulation type liquid ejection head. As shown in FIG. 8, the circulation common liquid chamber 50 is formed in the frame 1 in which the supply common liquid chamber 12 is formed.

Further, at the other end (left side in the figure) of the nozzle arrangement direction (left-right direction in the figure) of the circulation common liquid chamber 50, the first circulation communication portion, which is a circulation expansion part that reaches the outer peripheral surface of the liquid discharge head and communicates with the outside. 151a is provided, and a second circulation communication portion 151b, which is a circulation expansion portion, is provided at one end (right side in the figure). The other end of the first circulation connection pipe 91 to which the second coupling member 80b of the coupling 80 with a sealing function is attached to one end is attached to the first circulation communication portion 151a, and the second circulation communication portion 151b is attached. A second circulation connection pipe 92 having a sealing portion 93 formed by crushing at the tip thereof is attached to the surface. The second coupling member 80b is connected to the first coupling member attached to the tip of the circulation pipe connected to the head tank.

The first communication part 121a is provided on one end side in the nozzle arrangement direction, and the first circulation communication part 151a is provided on the other end side in the nozzle arrangement direction, but the present invention is not limited to this, and the first communication part is not limited to this. The 121a and the first circulation communication portion 151a may be provided on one end side in the nozzle arrangement direction. However, by providing the first communication portion 121a and the first circulation communication portion 151a on different end sides, one coupling 80 with a sealing function is provided on each of the one end side and the other end side in the nozzle arrangement direction. It will be arranged, and a well-balanced arrangement can be made, which is preferable.

Due to the ejection operation, air bubbles may be entrained from the nozzle 31 or ink that has not been sufficiently degassed may be used, so that air bubbles may be mixed into the individual liquid chamber 23. When air bubbles stay in the individual liquid chamber 23 in this way, the pressure change at the time of ink ejection is relaxed, which affects the ejection characteristics such as not being able to obtain a sufficient speed. Further, in the liquid ejection head 434, if the ink stays without being ejected for a long time, the volatile components volatilize from the nozzle 31 and the viscosity increases, the ejection characteristics change, or the ink sticks around the nozzle 31. This can cause bending of the discharge.

Therefore, in this modification, a circulation common liquid chamber 50 is provided, bubbles in the individual liquid chamber 23 and ink having an increased viscosity are flowed to the circulation common liquid chamber 50, and the ink is returned from the circulation common liquid chamber 50 to the head tank. Ink is circulated.

FIG. 9 is a block diagram showing an example of an ink circulation system.
As shown in FIG. 9, the ink circulation system includes a main tank 410, a liquid discharge head 434, a head tank 435, a supply side pump 438a, a circulation side pump 438b, a liquid feed pump 438c, a supply side pressure sensor 439a, and a circulation side pressure sensor. It is composed of 439b and the like. The supply-side pressure sensor 439a is provided between the supply-side pump 438a and the liquid discharge head 434. Further, the circulation side pressure sensor 439b is provided between the liquid discharge head 434 and the circulation side pump 438b. Then, the ink is flowed by the supply side pump 438a and the circulation side pump 438b so that the positive pressure is detected by the supply side pressure sensor 439a and the negative pressure is detected by the circulation side pressure sensor 439b. As a result, the head tank 435 flows into the supply common liquid chamber 12 through the first series passage portion 121a. The ink that has flowed into the common supply liquid chamber 12 flows through the individual liquid chamber 23 to the circulation common liquid chamber 50, is discharged from the first circulation communication portion 151a, and returns to the head tank 435, so that the ink circulates. In this example, the ink is circulated by a pump, but for example, the ink may be circulated by sending pressurized air into the head tank 435 to pressurize the ink.

Further, the supply side pump 438a and the circulation side pump 438b are constantly controlled so that the supply side pressure sensor 439a has a constant positive pressure and the circulation side pressure sensor 439b has a constant negative pressure. As a result, the negative pressure of the meniscus can be kept constant while circulating the ink through the liquid ejection head 434.

By circulating the ink in this way, the bubbles in the liquid ejection head 434 are discharged together with the ink from the first circulation communication portion 151a, and the bubbles in the liquid ejection head 434 can be removed. Further, the ink in which the volatile components are volatilized from the nozzle 31 and the viscosity is increased can be discharged from the first circulation communication portion 151a. Thereby, good discharge characteristics can be maintained. In addition, compared to the one in which the state of the droplets in the vicinity of the nozzle 31 is always maintained in a state suitable for ejection by ejecting the droplets periodically, wasteful consumption of ink is eliminated and the increase in running cost is suppressed. Can be done.

Further, when the droplets are ejected from the nozzle 31 of the liquid ejection head 434, the amount of ink in the head tank 435 decreases. Therefore, the ink is replenished to the head tank 435 from the main tank 410 by using the liquid feeding pump 438c as appropriate. It is desirable to do. The timing of ink replenishment from the main tank 410 to the head tank 435 is such that ink is replenished when the liquid level height of the ink in the head tank 435 falls below a predetermined height, such as a liquid level sensor provided in the head tank 435. It can be controlled by the detection result of.

FIG. 10 is a block diagram showing another example of the ink circulation system.
The liquid circulation system 530 shown in FIG. 10 includes a main tank 502, a liquid discharge head 434, a supply tank 531, a circulation tank 532, a compressor 533, a vacuum pump 534, a first liquid feed pump 535, a second liquid feed pump 536, and a supply side. It is composed of a pressure sensor 537, a circulation side pressure sensor 538, regulators (R) 539a, 539b and the like. The supply-side pressure sensor 537 is arranged between the supply tank 531 and the liquid discharge head 434. The circulation side pressure sensor 538 is connected between the liquid discharge head 434 and the circulation tank 532.

One of the circulation tanks 532 is connected to the supply tank 531 via the first liquid feed pump 535, and the other of the circulation tank 532 is connected to the main tank 502 via the second liquid feed pump 536. As a result, the ink flows from the supply tank 531 into the liquid discharge head 434, and the ink is discharged from the liquid discharge head to the circulation tank 532. Further, the liquid is circulated by being sent from the circulation tank 532 to the supply tank 531 by the first liquid feed pump 535. Further, a compressor 533 is connected to the supply tank 531 and is controlled so that a predetermined positive pressure is detected by the supply side pressure sensor 537. On the other hand, a vacuum pump 534 is connected to the circulation tank 532, and is controlled so that a predetermined negative pressure is detected by the circulation side pressure sensor 538. As a result, the negative pressure of the meniscus can be kept constant while circulating the liquid through the liquid discharge head 434.

Further, when the liquid is discharged from the nozzle 31 of the liquid discharge head 434, the amount of liquid in the supply tank 531 and the circulation tank 532 decreases. Therefore, it is desirable to replenish the liquid from the main tank 502 to the circulation tank 532 by appropriately using the second liquid feeding pump 536 from the main tank 502. The timing of liquid replenishment from the main tank 502 to the circulation tank 532 includes a liquid level sensor provided in the circulation tank 532, such as replenishing the liquid when the liquid level height of the ink in the circulation tank 532 drops below a predetermined height. It can be controlled by the detection result of.

The initial filling of the liquid discharge head of this modification is the first connection pipe 71 in which the second coupling member 80b of the coupling 80 with a sealing function is attached to one end of the first communication portion 121a of the liquid discharge head 434. One end of the second connecting pipe 72 made of a thermoplastic resin is attached to the second communication portion 121b. Next, the other end of the second connecting pipe 72 is connected to the waste liquid tank 82, and the second coupling member 80b is attached to the tip of the pipe connected to the ink liquid storage portion 81, the first coupling member 80a. Connect to.

Similarly, the other end of the first circulation connection pipe 9 to which the second coupling member 80b is attached to one end is attached to the first circulation communication portion 151a of the liquid discharge head 434, and the second circulation communication portion 151b is thermoplastic. One end of the second circulation connection pipe 92 made of resin is connected. Next, the other end of the second circulation connecting pipe 92 is connected to the waste liquid tank 82, and the second coupling member 80b is attached to the tip of the pipe connected to the ink liquid storage portion 81. Connect to 80a.

Next, the ink in the ink liquid storage unit is flowed by a pump or the like, and the ink is supplied to the supply common liquid chamber 12 and the circulation common liquid chamber 50. Then, ink flows into the common supply liquid chamber 12, the common circulation liquid chamber 50, and the individual liquid chambers 23, and the air in the common supply liquid chamber 12, the common circulation liquid chamber 50, and the individual liquid chambers 23 is also supplied. Is discharged from the second communication section 121b, and the air in the circulation common liquid chamber 50 is discharged from the second circulation communication section 151b. Next, when the ink is discharged from the second connecting pipe 72 and the second circulation connecting pipe 92 to the waste liquid tank 82, the supply of the ink is stopped. Then, the vicinity of the second communication portion 121b of the second connection pipe 72 and the vicinity of the second circulation communication portion 151b of the second circulation connection pipe 92 are crushed and welded to form the sealing portions 73 and 93, respectively.

In the ink circulation type liquid ejection head which does not have the second communication portion 121b and the second circulation communication portion 151b, the liquid ejection head cannot be filled with ink well, and the supply common liquid chamber 12 and the circulation common liquid chamber 50 cannot be filled. Air remains. Specifically, in an ink circulation type liquid ejection head that does not have a second communication section 121b and a second circulation communication section 151b, the communication section of the common supply liquid chamber 12 is connected to the ink liquid storage section 81 for common circulation. The communication portion of the liquid chamber 50 is connected to the waste liquid tank 82 to perform initial filling. However, if each individual liquid chamber 23 arranged below the common supply liquid chamber 12 is filled with the ink supplied to the common supply liquid chamber 12, the air in the common supply liquid chamber 12 cannot escape. Air remains in the common supply liquid chamber 12. Further, since the ink flowing from each individual liquid chamber 23 to the circulation common liquid chamber 50 flows toward the communication portion of the circulation common liquid chamber 50, the ink is ink at a place away from the communication portion of the circulation common liquid chamber 50. May stay and the air cannot be washed away, and the air may remain in the circulation common liquid chamber 50.

On the other hand, in this modification, by providing communication portions at both ends of the common supply liquid chamber 12, it is possible to supply ink from one communication portion and discharge air from the common supply liquid chamber from the other communication portion. .. As a result, it is possible to prevent air from remaining in the common supply liquid chamber 12. Further, by providing the circulation communication portions at both ends of the circulation common liquid chamber 50, the ink is discharged from the other circulation communication portion while the ink is supplied from one circulation communication portion, so that the ink is discharged from one end of the circulation common liquid chamber 50. Ink can flow toward the other end, and the air in the common liquid chamber can be satisfactorily discharged by the flow of ink. This makes it possible to prevent air from remaining in the circulating common liquid chamber.

Further, even in the modified example, the second connecting pipe 72 and the second circulation connecting pipe 92 are crushed to form an immutable sealing portion so that the liquid can flow after the initial filling, so that the second communication can be performed after the initial filling. It is possible to prevent air from entering from the portion 121b and the second circulation communication portion 151b. In addition, it is possible to reduce the cost and suppress the increase in size of the device.

Further, the second communication portion 121b and the second circulation communication portion 151b may be crushed to form a sealing portion. Further, three or more circulation communication portions may be provided. In the ink ejection operation, the circulation communication part for returning ink to the head tank has a connection part to which parts can be connected at the tip, and opens and closes the flow path between this connection part and the circulation communication part. A flow path forming means provided with a valve is connected, and the remaining circulation connection portion is sealed so that the parts cannot be attached or detached.

Next, an example of an apparatus for discharging a liquid to which the liquid discharge head 434 according to the embodiment can be applied will be described with reference to FIGS. 11 and 12. FIG. 11 is an explanatory plan view of a main part of the device for discharging the liquid according to the present embodiment, and FIG. 12 is an explanatory side view of the main part of the device for discharging the liquid according to the present embodiment. The device for discharging this liquid is a serial type device, and the carriage 503 is reciprocated in the main scanning direction by the main scanning moving mechanism 593. The main scanning movement mechanism 593 is composed of a guide member 501, a main scanning motor 505, a timing belt 508, and the like. The guide member 501 is bridged over the side plates 591A and 591B provided on both sides in the longitudinal direction of the device, and holds the carriage 503 movably. The carriage 503 is reciprocated by the main scanning motor 505 in the main scanning direction, which is the longitudinal direction of the device, via the timing belt 508 bridged between the drive pulley 506 and the driven pulley 507.

The carriage 503 is provided with a liquid discharge unit 540 equipped with a plurality of liquid discharge heads 434. In the liquid discharge unit 540, the liquid discharge head 434 discharges, for example, liquids of each color of yellow (Y), cyan (C), magenta (M), and black (K). Further, the liquid discharge head 434 has a nozzle row composed of a plurality of nozzles 31 arranged in a sub-scanning direction orthogonal to the main scanning direction, and is mounted with the discharge direction facing downward.

The device for discharging the liquid includes a transport mechanism 595 for transporting the paper 510. The transport mechanism 595 includes a transport belt 512 as a transport means, a sub-scanning motor 516 for driving the transport belt 512, and the like. The transport belt 512 attracts the paper 510 and transports it at a position facing the liquid discharge head 434. The transport belt 512 is an endless belt, and is hung between the transport roller 513 and the tension roller 514. The suction of the paper 510 to the transport belt 512 can be performed by electrostatic suction, air suction, or the like. The transfer belt 512 orbits in the sub-scanning direction by rotationally driving the transfer roller 513 via the timing belt 517 and the timing pulley 518 by the sub-scanning motor 516.

On one side of the carriage 503 in the main scanning direction, a maintenance / recovery mechanism 520 that maintains and recovers the liquid discharge head 434 is arranged on the side of the transport belt 512. The maintenance / recovery mechanism 520 is composed of, for example, a cap member 521 that caps the nozzle surface (the surface on which the nozzle 31 is formed) of the liquid discharge head 434, a wiper member 522 that wipes the nozzle surface, and the like.

The main scanning movement mechanism 593, the maintenance / recovery mechanism 520, and the transport mechanism 595 are attached to a housing composed of side plates 591A, 591B, a back plate 591C, and the like. In the device for ejecting the liquid configured in this way, the paper 510 is fed onto the transport belt 512 and adsorbed, and the paper 510 is conveyed in the sub-scanning direction by the circumferential movement of the conveyor belt 512. Then, by driving the liquid ejection head 434 in response to the image signal while moving the carriage 503 in the main scanning direction, the liquid is ejected onto the stopped paper 510 to form an image. As described above, since the device for discharging the liquid is provided with the liquid discharge head 434, it is possible to stably form a high-quality image.

Next, another example of the liquid discharge unit 540 will be described with reference to FIG. FIG. 13 is an explanatory plan view of a main part of the unit. The liquid discharge unit 540 includes a housing portion composed of side plates 591A and 591B and a back plate 591C, a main scanning moving mechanism 593, a carriage 503, and a member constituting the device for discharging the liquid. It is composed of a liquid discharge head 434. It is also possible to configure the liquid discharge unit 540 in which at least one of the above-mentioned maintenance and recovery mechanisms 520 is further attached to, for example, the side plate 591B of the liquid discharge unit 540.

In the present embodiment, the "liquid discharge head" is a functional component that discharges and injects liquid from a nozzle. The liquid to be discharged may have a viscosity and surface tension that can be discharged from the head, and is not particularly limited, but the viscosity becomes 30 [mPa · s] or less at room temperature, under normal pressure, or by heating or cooling. It is preferable that it is a thing. More specifically, solvents such as water and organic solvents, colorants such as dyes and pigments, functionalizing materials such as polymerizable compounds, resins and surfactants, biocompatible materials such as DNA, amino acids and proteins, and calcium. , Solutions, suspensions, emulsions and the like containing edible materials such as natural pigments. These can be used, for example, in inks for inkjet, surface treatment liquids, liquids for forming electronic elements and light emitting elements, liquids for forming electronic circuit resist patterns, and liquids for three-dimensional modeling. Piezoelectric actuators (laminated piezoelectric elements and thin-film piezoelectric elements), thermal actuators that use electric heat conversion elements such as heat-generating resistors, and electrostatic actuators that consist of a vibrating plate and counter electrodes are used as energy sources for discharging liquid. Includes what to do.

The "liquid discharge unit" is a liquid discharge head integrated with functional parts and a mechanism, and is a collection of parts related to liquid discharge. For example, the "liquid discharge unit" includes a combination of at least one of a supply circulation mechanism, a carriage, a maintenance / recovery mechanism, and a main scanning movement mechanism with a liquid discharge head. Here, the term "integration" means, for example, a liquid discharge head and a functional component, a mechanism in which the mechanism is fixed to each other by fastening, bonding, engagement, etc., or one in which one is movably held with respect to the other. include. Further, the liquid discharge head, the functional component, and the mechanism may be configured to be detachable from each other.

For example, there is a liquid discharge unit in which a liquid discharge head and a supply circulation mechanism are integrated. In some cases, the liquid discharge head and the supply / circulation mechanism are integrated by being connected to each other by a tube or the like. Here, a unit including a filter can be added between the supply circulation mechanism of these liquid discharge units and the liquid discharge head. Further, as a liquid discharge unit, there is a unit in which a liquid discharge head and a carriage are integrated. Further, there is a liquid discharge unit in which the liquid discharge head and the scanning movement mechanism are integrated by holding the liquid discharge head movably by a guide member constituting a part of the scanning movement mechanism. Further, as a liquid discharge unit, there is a carriage to which a liquid discharge head is attached, in which a cap member which is a part of the maintenance / recovery mechanism is fixed, and the liquid discharge head, the carriage, and the maintenance / recovery mechanism are integrated. .. Further, as a liquid discharge unit, there is a liquid discharge unit in which a tube is connected to a liquid discharge head to which a supply circulation mechanism or a flow path component is attached, and the liquid discharge head and the supply mechanism are integrated. The liquid of the liquid storage source is supplied to the liquid discharge head through this tube. The main scanning movement mechanism shall include a single guide member. Further, the supply mechanism shall include a single tube and a single loading unit.

The "device for discharging a liquid" is a device provided with a liquid discharge head or a liquid discharge unit and driving the liquid discharge head to discharge the liquid. The device for discharging the liquid includes not only a device capable of discharging the liquid to a device to which the liquid can adhere, but also a device for discharging the liquid into the air or into the liquid. The "device for discharging the liquid" may include means for feeding, transporting, and discharging paper to which the liquid can adhere, as well as a pretreatment device, a posttreatment device, and the like.

For example, as a "device that ejects a liquid", an image forming device that is a device that ejects ink to form an image on paper, and a three-dimensional model (three-dimensional model) are formed in layers in order to form a three-dimensional model. There is a three-dimensional modeling device (three-dimensional modeling device) that discharges the modeling liquid into the powder layer. Further, the "device for discharging a liquid" is not limited to a device in which a significant image such as characters and figures is visualized by the discharged liquid. For example, those that form patterns that have no meaning in themselves and those that form a three-dimensional image are also included.

The above-mentioned "thing to which a liquid can adhere" means a material to which a liquid can adhere at least temporarily, such as a material to which the liquid adheres and adheres, and a material to which the liquid adheres and permeates. Specific examples include paper, recording paper, recording paper, film, recorded media such as cloth, electronic substrates, electronic components such as piezoelectric elements, powder layers (powder layers), organ models, and media such as inspection cells. Yes, and includes everything to which the liquid adheres, unless otherwise specified. The material of the above-mentioned "material to which liquid can adhere" may be paper, thread, fiber, cloth, leather, metal, plastic, glass, wood, ceramics or the like as long as the liquid can adhere even temporarily.

The "liquid" may have a viscosity and surface tension that can be discharged from the head, and is not particularly limited, but has a viscosity of 30 [mPa · s] or less at room temperature, under normal pressure, or by heating or cooling. It is preferable that it becomes. More specifically, solvents such as water and organic solvents, colorants such as dyes and pigments, functionalizing materials such as polymerizable compounds, resins and surfactants, biocompatible materials such as DNA, amino acids and proteins, and calcium. , Solutions, suspensions, emulsions and the like containing edible materials such as natural pigments. These can be used, for example, in inks for inkjet, surface treatment liquids, liquids for forming electronic elements and light emitting elements, liquids for forming electronic circuit resist patterns, and liquids for three-dimensional modeling.

Further, the "device for discharging the liquid" includes, but is not limited to, a device in which the liquid discharge head and the device to which the liquid can adhere move relatively. Specific examples include a serial type device that moves the liquid discharge head, a line type device that does not move the liquid discharge head, and the like. In addition, as a "device for ejecting liquid", there is a treatment liquid coating device for ejecting the treatment liquid to the paper in order to apply the treatment liquid to the surface of the paper for the purpose of modifying the surface of the paper. be. Further, there is an injection granulation device that granulates fine particles of a raw material by injecting a composition liquid in which a raw material is dispersed in a solution through a nozzle. Further, in the terms of the present application, image formation, recording, printing, printing, printing, modeling, etc. are all synonymous.

What has been described above is an example, and has a unique effect in each of the following aspects.
(Aspect 1)
It is provided with a plurality of nozzles 31 for ejecting a liquid such as ink, a plurality of individual liquid chambers 23 communicating with the plurality of nozzles, and a common liquid chamber such as a supply common liquid chamber 12 communicating with the plurality of individual liquid chambers 23. The chamber is a liquid discharge head having a plurality of expansion portions such as communication portions 121a and 121b reaching the outside of the head, and at least one of the plurality of expansion portions is a connection portion such as a coupling member to which parts can be connected. , A flow path forming means provided with an on-off valve 80b2 for opening and closing a flow path between the connection portion and the common liquid chamber (in the present embodiment, a second coupling having a first connection pipe 71 and an on-off valve 80b2). (Consists of member 80b) is connected, and the remaining expansion portion is immutably sealed so that the liquid can flow.
In the liquid discharge head described in Patent Document 1, all the expansion portions are connected to a flow path forming means provided with a connection portion such as a joint and an on-off valve, which leads to an increase in cost.
Therefore, in the first aspect, at least one of the plurality of expansion portions includes a connection portion such as a coupling member to which parts can be connected, and an on-off valve that opens and closes a flow path between the connection portion and the common liquid chamber. The flow path forming means provided with the above was connected, and the remaining expansion portion was immutably sealed so that the liquid could flow. For sealing, which cannot be changed to a state in which a liquid flows, that is, a state in which no flow occurs, a cylindrical member such as an expansion part or a tube connected to the expansion part is crushed and sealed after initial filling. It can be obtained by forming a portion. In this way, by sealing the expansion portion in an immutable state so that the liquid can flow, it is possible to prevent air or the like from entering the common liquid chamber from the expansion portion after the initial filling. Further, the cost of the device can be reduced as compared with the case where the flow path forming means provided with the connection portion and the on-off valve is connected to all the expansion portions.
Further, at least one of the plurality of expansion portions is connected to the flow path means provided with the connection portion and the on-off valve, and when the operation of discharging the liquid is performed, the liquid supply means is connected to this connection portion. By doing so, the liquid consumed by the discharge of the liquid can be replenished to the liquid discharge head.

(Aspect 2)
In the first aspect, the remaining expansion is provided by providing the sealing portion 73 in which the cylindrical member such as the second connecting pipe 72 connected to the remaining expansion portion such as the second communication portion 121b or the remaining expansion portion is crushed. The part was immutably sealed so that the liquid could flow.
According to this, as described in the embodiment, after the initial filling operation, the tubular member such as the second connecting pipe 72 or the remaining expansion portion such as the second communication portion 121b is crushed to form the sealing portion 73. It is possible to prevent problems such as air entering the head through the remaining expansion part, as compared with the case where the tubular member and the remaining expansion part are closed and sealed with, for example, a cap member. can do.

(Aspect 3)
In the second aspect, the inner layer of the remaining expansion portion such as the second communication portion 121b or the inner layer of the tubular member such as the second connecting pipe 72 connected to the expansion portion is formed of a thermoplastic resin, and the inner layer is formed. The sealing portion 73 is formed by welding.
According to this, as described in the embodiment, the sealing portion 73 can be formed more easily than the sealing portion 73 is formed by crimping the metal.

(Aspect 4)
In any one of aspects 1 to 3, the common liquid chamber is a supply common liquid chamber 12 that supplies a liquid such as ink to the individual liquid chamber 23, and an extension such as a communication portion is provided at both ends of the common liquid chamber 12 in the nozzle arrangement direction. The part is formed.
According to this, as described in the embodiment, at the time of initial filling, while supplying liquid such as ink from the expansion portion such as the communication portion at one end in the nozzle arrangement direction of the supply common liquid chamber 12, the expansion portion at the other end. The air in the common supply liquid chamber can be discharged from the liquid chamber 12, and the liquid can be satisfactorily filled in the common supply liquid chamber 12 by suppressing the residual air in the common supply liquid chamber 12.

(Aspect 5)
In the fourth aspect, there is a circulation common liquid chamber 50 in which a liquid such as ink flows from a plurality of individual liquid chambers 23, and the circulation common liquid chamber 50 is a circulation expansion of a plurality of circulation communication portions 151a, 151b and the like reaching the outside of the head. At least one of the plurality of circulation expansion portions has a connection portion such as a second coupling member 80b to which parts can be connected, and a flow path between the connection portion and the circulation common liquid chamber 50. A flow path forming means (in this embodiment, composed of a first circulation connection pipe 91 and a second coupling member having an on-off valve) provided with an on-off valve 80b2 for opening and closing is connected, and the remaining circulation is provided. The extension is immutably sealed so that the liquid can flow.
According to this, as described in the modified example, at the time of initial filling, liquid is supplied from at least one of the plurality of circulation expansion portions, and air is discharged from the remaining circulation expansion portions, so that the circulation common liquid chamber is used. The liquid can be filled in 50, and it is possible to suppress the residual air in the circulation common liquid chamber 50.
Further, after the initial filling, by crushing and sealing the cylindrical member such as the remaining circulation expansion portion and the second circulation connection pipe 92 connected to the remaining circulation expansion portion, air does not enter. , Parts can be sealed inaccessible. Further, the cost of the device can be reduced as compared with the case where the flow path forming means provided with the connection portion and the on-off valve is connected to all the circulation expansion portions.
Further, at least one of the plurality of circulation expansion portions is connected to the flow path forming means provided with the connection portion and the on-off valve, and when the operation of discharging the liquid is performed, the connection portion is connected to the head tank. By connecting the flow path forming member for returning, the liquid in the liquid discharge head can be circulated.

(Aspect 6)
In the fifth aspect, circulation expansion portions such as circulation communication portions 151a and 151b are provided at both ends of the circulation common liquid chamber 50 in the nozzle arrangement direction.
According to this, as described in the modified example, in the initial filling, the nozzle arrangement direction and the like while supplying the liquid such as ink from the circulation expansion portion such as the circulation communication portion at one end of the nozzle arrangement direction of the circulation common liquid chamber 50. The air in the circulation common liquid chamber 50 can be discharged from the circulation expansion part such as the circulation communication part at the end, the liquid can be satisfactorily filled in the circulation common liquid chamber, and the air remains in the circulation common liquid chamber 50. Can be suppressed.

(Aspect 7)
In the device for discharging the liquid provided with the liquid discharge head 434 for discharging the liquid, the liquid discharge head according to any one of aspects 1 to 6 was used as the liquid discharge head.
According to this, it is possible to reduce the cost of the device and suppress the increase in size of the device.

(Aspect 8)
A plurality of nozzles 31 for discharging liquid, a plurality of individual liquid chambers 23 communicating with the plurality of nozzles 31, and a common liquid chamber such as a supply common liquid chamber 12 communicating with the plurality of individual liquid chambers 23 are provided and common. The liquid chamber is a component connected to at least one of a plurality of expansion portions in a method for manufacturing a liquid discharge head having expansion portions such as a plurality of communication portions 121a and 121b reaching the outside of the head. A step of connecting a flow path forming means including a connection portion such as a possible second coupling member 80b and an on-off valve 80b2 for opening and closing a flow path between the connection portion and the common liquid chamber, and a plurality of expansion portions. The liquid flows to the step of supplying the liquid to the common liquid chamber from at least one of the above and filling the liquid into the liquid discharge head, and to the remaining expansion portion such as the second communication portion 121b to which the flow path forming means is not connected. It has a step of forming a sealing portion 73 which cannot be changed to such a state.
According to this, as described in the embodiment, it is possible to suppress the intrusion of air into the liquid discharge head and to manufacture the liquid discharge head at low cost.

(Aspect 9)
In the eighth aspect, the remaining expansion portion such as the second communication portion 121b or the tubular member such as the second connection pipe 72 connected to the remaining expansion portion is welded by welding to form the sealing portion 73. bottom.
According to this, as described in the embodiment, the sealing portion can be easily formed.

12: Supply common liquid chamber 23: Individual liquid chamber 31: Nozzle 50: Circulation common liquid chamber 71: First connection pipe 72: Second connection pipe 73: Sealing portion 74: Supply pipe 80: Coupling 80a with sealing function : First coupling member 80b: Second coupling member 81: Ink liquid storage part 82: Waste liquid tank 91: First circulation connection pipe 92: Second circulation connection pipe 93: Sealing part 121a: First connection part 121b: Second circulation connection 151a: First circulation connection 151b: Second circulation connection 434: Liquid discharge head 435: Head tank

Japanese Unexamined Patent Publication No. 2012-6374

Claims (6)

Multiple nozzles that eject liquid and
Multiple individual liquid chambers leading to each of the plurality of nozzles,
A supply common liquid chamber that leads to the plurality of individual liquid chambers and supplies the liquid to the individual liquid chambers is provided.
In the liquid discharge head having expansion portions reaching the outside of the head at both ends in the nozzle arrangement direction of the common supply liquid chamber, respectively .
At least one of the plurality of expansion portions is connected to a flow path forming means including a connection portion to which parts can be connected and an on-off valve for opening and closing the flow path between the connection portion and the supply common liquid chamber. The remaining extension is immutably sealed so that the liquid can flow.
It has a circulation common liquid chamber into which the liquid flows from a plurality of the individual liquid chambers.
The circulation common liquid chamber has a plurality of circulation expansion portions extending to the outside of the head.
At least one of the plurality of circulation expansion portions is a flow path forming means provided with a connection portion to which parts can be connected and an on-off valve for opening and closing the flow path between the connection portion and the circulation common liquid chamber. A liquid discharge head that is connected and the remaining circulation extension is immutably sealed so that the liquid can flow . In the liquid discharge head according to claim 1,
By providing a sealing portion in which the tubular member connected to the remaining expansion portion or the remaining expansion portion is crushed, the remaining expansion portion is immutably sealed so that the liquid can flow. A liquid discharge head characterized by that. In the liquid discharge head according to claim 2,
The inner layer of the remaining expansion portion or the inner layer of the tubular member connected to the remaining expansion portion is formed of a thermoplastic resin, and the inner layer is welded to form the sealing portion. Characterized liquid discharge head . In the liquid discharge head according to any one of claims 1 to 3.
A liquid discharge head characterized in that the circulation expansion portions are provided at both ends of the circulation common liquid chamber in the nozzle arrangement direction. In a device that discharges a liquid equipped with a liquid discharge head that discharges the liquid,
A device for discharging a liquid, wherein the liquid discharge head according to any one of claims 1 to 4 is used as the liquid discharge head. A plurality of nozzles for discharging liquid, a plurality of individual liquid chambers communicating with each of the plurality of nozzles, and a common liquid chamber communicating with the plurality of individual liquid chambers are provided, and the common liquid chambers reach the outside of the head. In the method of manufacturing a liquid discharge head for manufacturing a liquid discharge head having an expansion portion of
At least one of the plurality of expansion portions is connected to a flow path forming means provided with a connection portion to which components can be connected and an on-off valve for opening and closing the flow path between the connection portion and the common liquid chamber. Process and
A step of supplying a liquid from at least one of a plurality of expansion portions to the common liquid chamber and filling the liquid discharge head with the liquid.
In a state where the tubular member connected to the remaining expansion portion to which the flow path forming means is not connected is filled with a liquid, between one end of the tubular member and the other end connected to the expansion portion. A method for manufacturing a liquid discharge head, which comprises a step of welding to form a sealed portion to which parts cannot be connected .

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