JP6900675B2 - Liquid discharge head, liquid discharge unit and device that discharges liquid - Google Patents

Description

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

Image forming devices such as printers, facsimiles, copying machines, plotters, and multifunction devices thereof include, for example, a liquid discharge head or a liquid discharge unit, and drive the liquid discharge head to discharge liquid (for example, inkjet recording). Equipment) etc. are known.

The liquid discharge head includes a nozzle that discharges a liquid, an individual liquid chamber that communicates with the nozzle and stores the liquid, a pressure generating means (driving means or an energy generating means) that pressurizes the liquid in the individual liquid chamber, and an individual liquid chamber. It is provided with a common liquid chamber for storing the liquid flowing into the liquid chamber, and pressurizes the ink in the individual liquid chambers by driving the pressure generating means, ejects ink droplets from the nozzle, and lands on the recording medium.

Recently, an on-demand liquid ejection head (inkjet head) configured to eject minute droplets of ink only when recording (printing) is required has become mainstream.
Printing with inkjet heads is required to output high image quality not only for consumer use but also for industrial use, and there are many demands for on-demand printing in the field of large signboard and poster printing, and on-demand inkjet recording. Devices are becoming more popular.

In recent years, there has been a demand for miniaturization and cost reduction of the device, and for the inkjet head, the nozzle mounting density, that is, the reduction of the nozzle spacing in the nozzle row, and the inter-row distance of each of a plurality of nozzle rows There is a demand for miniaturization of the inkjet head by reduction and an increase in the number of nozzles.

The inkjet recording device is equipped with a drive circuit (triver IC) for driving the inkjet head. Since the drive circuit outputs a drive signal to the inkjet head, a large current flows momentarily and the temperature rises sharply, but the temperature rise also becomes remarkable due to the increase in the number and density of drive elements accompanying the increase in the number of nozzles. There is a problem.
In particular, in an industrial inkjet head, more heat is generated by continuously performing a driving operation for a long time, so that an efficient heat dissipation function is required.

On the other hand, in order to reduce the size of the device, an inkjet head having a configuration in which the head body and the cable are separated to save space has been proposed. In a conventional inkjet head having such a separate structure, a heat radiating member (heat sink) having a role of releasing heat generated in a drive circuit to the outside is installed inside the head body.

By increasing the amount of heat radiated from the heat radiating member, the maximum allowable drive frequency increases, and as a result, the maximum discharge amount increases. However, in the configuration in which the heat radiating member is provided inside the head body, the portion of the heat radiating member in contact with the outside air is small and the amount of heat released is small, so that the maximum drive frequency and the maximum discharge amount are limited.
Further, when assembling the head body, the head cover may push the heat radiating member inside and come into contact with another member (for example, SUS base).

On the other hand, an inkjet recording device has been proposed that has a simple configuration, is easy to assemble, and can efficiently dissipate heat generated by a drive circuit (see, for example, Patent Document 1).
Patent Document 1 has a first heat sink and a second heat sink arranged in a substantially square shape having a space inside, and one ends of the first heat sink and the second heat sink are connected to each other. The other end is disclosed as having a heat radiating member having a structure in which a heat generating portion of a drive circuit is sandwiched between the other ends.

However, with the increase in the number of nozzles of the inkjet head, in a configuration in which a large number of drive elements are provided at a high density, each driver IC is sandwiched between the first heat sink and the second heat sink as described in Patent Document 1. Increasing the heat dissipation efficiency as a configuration leads to a complicated structure and an increase in cost.

Therefore, an object of the present invention is to provide a liquid discharge head capable of achieving both excellent assembling property and excellent heat dissipation efficiency and realizing an increase in the maximum discharge amount.

In order to achieve such an object, the liquid discharge head according to the present invention controls the drive of the pressure generating element in the liquid discharge head that applies pressure to the liquid in the pressure chamber by driving the pressure generating element and discharges the liquid from the nozzle. The drive control unit, a heat radiating member in contact with the drive control unit, and a cover member covering the drive control unit and a part of the heat radiating member are provided, and the heat radiating member is arranged outside the cover member. It is composed of a first heat radiating member which is provided and has a surface in contact with the outside air, and a second heat radiating member which is arranged inside the cover member and has an end portion which is in contact with the drive control unit. The heat radiating member and the second heat radiating member are in contact with each other.

According to the present invention, it is possible to provide a liquid discharge head capable of achieving both excellent assembling property and excellent heat dissipation efficiency and increasing the maximum discharge amount.

It is a side view (A), a front view (B), and a schematic view (C) which shows the schematic structure inside the head of the conventional inkjet head. It is a side view (A) of the main body which constitutes the conventional inkjet head, the front view (B) of the main body, and the cross-sectional view (C) which shows the schematic structure inside the main body. It is a schematic diagram which shows the state which the head body and the head cable part are separated. It is a schematic diagram which shows disassembled the flow path unit and a housing which make up a liquid chamber part. It is a main body side view (A), the main body front view (B), and the cross-sectional view (C) which shows the schematic structure inside the main body which comprises the liquid discharge head which concerns on 1st Embodiment. It is explanatory drawing which shows an example of the structure of the heat dissipation member of FIG. It is sectional drawing which shows the schematic structure of the inside of the main body which comprises the liquid discharge head which concerns on 2nd Embodiment. It is explanatory drawing which shows an example of the structure of the heat dissipation member of FIG. It is explanatory drawing which shows an example of the attachment method of a heat radiating member. It is sectional drawing which shows the schematic structure of the inside of the main body which comprises the liquid discharge head which concerns on 3rd Embodiment. It is explanatory drawing which shows an example of the structure of the heat dissipation member of FIG. It is a main body side view (A), the main body front view (B), and the cross-sectional view (C) which shows the schematic structure inside the main body which comprises the liquid discharge head which concerns on 4th Embodiment. It is explanatory drawing which shows an example of the structure of the heat dissipation member of FIG. It is a main body side view (A), the main body front view (B), and the cross-sectional view (C) which shows the schematic structure inside the main body which comprises the liquid discharge head which concerns on 5th Embodiment. It is explanatory drawing which shows an example of the structure of the heat dissipation member of FIG. It is a figure which shows an example of the apparatus which discharges a liquid, (A) is a perspective view which shows the outline of the main part structure, (B) is a side view. It is a side view which shows an example of a liquid discharge unit. It is a top view which shows an example of a liquid discharge unit. It is a side view which shows an example of a liquid discharge unit.

Hereinafter, the liquid discharge head, the liquid discharge unit, and the device for discharging the liquid according to the present invention will be described with reference to the drawings. The present invention is not limited to the embodiments shown below, and can be modified within the range conceivable by those skilled in the art, such as other embodiments, additions, modifications, and deletions. However, as long as the action and effect of the present invention are exhibited, it is included in the scope of the present invention.

[Liquid discharge head]
In the present application, the "liquid discharge head" is a functional component that discharges and ejects a 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 has a viscosity of 30 mPa · s or less at room temperature, under normal pressure, or by heating or cooling. Is preferable. More specifically, solvents such as water and organic solvents, colorants such as dyes and pigments, polymerizable compounds, resins, functionalizing materials such as surfactants, biocompatible materials such as DNA, amino acids and proteins, and calcium. , Solvents, suspensions, emulsions, etc. containing edible materials such as natural pigments, etc., for example, inks for inkjets, surface treatment liquids, constituents of electronic elements and light emitting elements, and formation of electronic circuit resist patterns. It can be used for applications such as a liquid for use and a material liquid for three-dimensional modeling.

Piezoelectric actuators (laminated piezoelectric elements and thin-film piezoelectric elements), thermal actuators that use electrothermal 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 use.

In addition, image formation, recording, printing, printing, printing, modeling, etc. in the terms of the present application are all synonymous.

First, the structure of the inkjet head as a conventional liquid discharge head will be described with reference to FIGS. 1 to 3.

1A is a side view of the inkjet head, FIG. 1B is a front view of the inkjet head, and FIG. 1C is a schematic configuration of the inside of the inkjet head body.
The inkjet head shown in FIG. 1 has a structure in which a head body and a cable portion (wiring member) are integrated, and a heat radiating member 1 protrudes from above the cover member 4.

As shown in FIG. 1 (C), the drive control unit 3 is joined to both sides of each of the two heat radiating members 1.
The drive control unit 3 is connected to the wiring member 2. The wiring member 2 extends from the head body and is connected to the connector board 5 and the connector 6.

2 and 2 show an example in which the head body and the cable portion (wiring member) can be separated from the inkjet head shown in FIG. 1, and the heat radiating member is housed inside the head body to save space. Shown in 3.

2A and 2B schematically show the separated head main body, FIG. 2A is a side view, FIG. 2B is a front view, and FIG. 2C is a cross-sectional view showing a schematic internal configuration. FIG. 3 is a schematic view showing a state in which the head main body 7 and the cable portion 8 are separated.

As shown in FIG. 3, by separating the head body 7 and the cable portion 8, the space of the inkjet head can be saved.
When the head main body 7 and the cable portion 8 are separated, it is difficult to connect the cable portion 8 in a structure in which the heat radiating member 1 protrudes from the upper part of the main body such as the conventional inkjet head shown in FIG. Therefore, in the present embodiment, the heat radiating member 1 is housed inside the cover member 4 as shown in FIG. 2 (C). In order to improve the heat dissipation efficiency, a window portion is provided on the front surface of the cover member 4, and a part of the heat dissipation member 1 is exposed to the outside from the window portion.

The configuration of the liquid chamber portion 11 shown in FIG. 2 (B) is shown in FIG.
FIG. 4 is a schematic view showing the flow path unit and the housing constituting the liquid chamber portion 11 in an exploded manner. The liquid chamber portion 11 is composed of a housing 12, a filter plate 13, a manifold 14, a diaphragm 15, a restrictor plate 16, and an orifice plate 17.

The diaphragm 15 is joined to the pressure generating element 10.
When a voltage is applied to the pressure generating element 10 joined to the SUS base 9, the pressure generating element 10 is distorted, and the individual liquid chamber composed of the restrictor plate 16 is compressed via the diaphragm 15 to compress the individual liquid chamber, and the orifice plate 17 Ink is ejected from the nozzle hole of. At this time, heat is generated in the drive control unit 3. The generated heat is released to the outside by the heat radiating member 1 joined to the drive control unit 3.

However, in the structures shown in FIGS. 2 and 3, the amount of heat dissipated by the heat radiating member 1 is not sufficient, and the maximum drive frequency and the maximum discharge amount are limited.
On the other hand, according to the liquid discharge head of the present invention shown below, both space saving and excellent heat dissipation efficiency can be achieved at the same time, and the maximum discharge amount can be increased.

The liquid discharge head of the present invention includes a drive control unit 3 that controls the drive of the pressure generating element 10 in the liquid discharge head that applies pressure to the liquid in the pressure chamber by driving the pressure generating element 10 and discharges the liquid from the nozzle. A heat radiating member 1 in contact with the drive control unit 3 and a cover member 4 covering a part of the drive control unit 3 and the heat radiating member 1 are provided, and the heat radiating member 1 is arranged outside the cover member 4 and has outside air. It is composed of a first heat radiating member 1a having a surface in contact with the cover member 4 and a second heat radiating member 1b arranged inside the cover member 4 and having an end portion in contact with the drive control unit 3, and is composed of the first heat radiating member 1a. And the second heat radiating member 1b come into contact with each other.
Specifically, a flow path unit formed by stacking members having functions of a nozzle, a pressure chamber, and a restrictor, and a pressure generating element 10 that is joined to the flow path unit to generate pressure for discharging liquid. , A liquid chamber portion 11 including a housing 12 that houses the pressure generating element 10 and is laminated on the flow path unit, and a bendable upper device transmission wiring member 2b that transmits an electric signal from the upper device. , The relay wiring member 2a connecting between the host device transmission wiring member 2b and the pressure generating element 10 and the relay wiring member 2a mounted on the relay wiring member 2a to control the drive of the pressure generating element 10 based on the electric signal from the host device. It includes a drive control unit 3, a cover member 4 that houses and protects the relay wiring member 2a and the drive control unit 3, and a heat radiation member (heat source) 1 for dissipating heat generated by the drive control unit 3 to the outside.

(First Embodiment)
The first embodiment of the present invention will be described with reference to FIGS. 5 and 6.
In the liquid discharge head of the present embodiment, the wiring member 2 for transmitting a signal to the drive control unit is provided so as to be separable from the head main body 7 having the heat dissipation member. Specifically, the cable portion 8 having the host device transmission wiring member 2b is provided so as to be separable from the head main body 7 having the liquid chamber portion 11, the cover member 4, and the heat radiating member 1.
5A and 5B are schematic views showing a head main body 7 constituting the liquid discharge head of the present embodiment, where FIG. 5A is a side view, FIG. 5B is a front view of the main body, and FIG. It is a cross-sectional view.
FIG. 6 is an explanatory diagram showing the configuration of the heat radiating member 1 of the present embodiment.

As shown in FIG. 5, the heat radiating member 1 is arranged outside the cover member 4, the first heat radiating member 1a having a surface in contact with the outside air, and the heat radiating member 1 inside the cover member 4, and the drive control unit 3 It is composed of a second heat radiating member 1b having an end portion that comes into contact with the first heat radiating member 1a and the second heat radiating member 1b.
With such a configuration, only one surface of the first heat radiating member 1a is exposed to the outside, and the surface in contact with the second heat radiating member 1b is not exposed. It is possible to prevent deterioration of the appearance.
As shown in FIGS. 5A and 5C, the heat radiating member 1 is provided on both opposite surfaces.

The first heat radiating member 1a constituting the heat radiating member 1 will be described with reference to FIG. 6B.
The surface S1 of the first heat radiating member 1a is joined to the cover member 4 of the head body, and the surface S2 is in contact with the outside air. The first heat radiating member 1a is arranged so as to cover the side surface of the cover member 4 in the longitudinal direction, but the sealing property can be improved by increasing the joint area between the surface S1 and the cover member 4. ..
The area ratio of the side surface of the cover member 4 in the longitudinal direction covered by the first heat radiating member 1a is preferably half or more, and more preferably the entire surface.

Since the end of the second heat radiating member 1b is connected to the drive control unit 3, the heat generated by the drive control unit 3 is transmitted to the second heat radiating member 1b and further has a surface in contact with the outside air. It is transmitted to the member 1a and efficiently dissipates heat.

(Second embodiment)
A second embodiment of the present invention will be described with reference to FIGS. 7 and 8.
In the liquid discharge head of the present embodiment, the wiring member 2 for transmitting a signal to the drive control unit 3 is provided so as to be separable from the head main body 7 having the heat dissipation member 1.
Specifically, the cable portion 8 including the host device transmission wiring member 2b is provided so as to be separable from the head main body 7 having the liquid chamber portion 11, the cover member 4, and the heat radiating member 1.
FIG. 7 is a cross-sectional view showing a schematic configuration of the inside of the head main body 7 constituting the liquid discharge head of the present embodiment. FIG. 8 is an explanatory diagram showing the configuration of the heat radiating member 1 of the present embodiment.

As shown in FIGS. 7 and 8, the heat radiating member 1 of the present embodiment is disposed outside the cover member 4, and is arranged inside the first heat radiating member 1a having a surface in contact with the outside air and inside the cover member 4. The first heat radiating member 1a has an engaging portion having an L-shaped cross section and is composed of a second heat radiating member 1b having an end portion that is provided and has an end portion that comes into contact with the drive control unit 3, and the second heat radiating member 1b. The engaging portion of the above and the engaging portion come into contact with each other.
The first heat radiating member 1a has an engaging portion protruding from the plate-shaped portion, the engaging portion abuts on the engaging portion of the second heat radiating member 1b, and one surface of the plate-shaped portion is a cover member 4. The other surface is in contact with the outside air. Similar to the first embodiment described above, the first heat radiating member 1a is arranged so as to cover the side surface of the cover member 4 in the longitudinal direction.

The second heat radiating member 1b has a stepped structure, one end of which is in contact with the drive control unit 3 and the other end of which is in contact with the inner surface of the cover member 4. Since the end of the second heat radiating member 1b is in contact with the drive control unit 3, the heat generated by the drive control unit 3 is transmitted to the second heat radiating member 1b and further has a surface in contact with the outside air. It is transmitted to the member 1a and efficiently dissipates heat.

FIG. 9 shows a method of attaching the first heat radiating member 1a to the main body of the liquid discharge head of the present embodiment.
The cover member 4 of the head body 7 is provided with a hole 41 for inserting the engaging portion of the first heat radiating member 1a. By inserting the first heat radiating member 1a in the direction of arrow D1 and then pushing it in the direction of arrow D2, the first heat radiating member 1a comes into contact with the engaging portion of the second heat radiating member 1b arranged earlier, as shown in FIG. Connected in the state.
As described above, according to the present embodiment, excellent assembling property can be obtained. That is, it can be easily assembled and the assembling property is improved. Further, since only one surface of the first heat radiating member 1a is exposed to the outside and the surface in contact with the second heat radiating member 1b is not exposed, it is necessary to prevent deterioration of the appearance due to the adhesive squeezing out. Can be done.

Contrary to the above, an L-shaped engaging portion may be provided on the second heat radiating member 1b side, and the end portion of the first heat radiating member 1a may be fitted into the engaging portion. An L-shaped engaging portion may be provided on both the first heat radiating member 1a and the second heat radiating member 1b, and may be combined and brought into contact with each other.
That is, it is preferable that at least one of the first heat radiating member 1a and the second heat radiating member 1b has an engaging portion having an L-shaped cross section and comes into contact with the engaging portion via the engaging portion.

(Third embodiment)
A third embodiment of the present invention will be described with reference to FIGS. 10 and 11.
In the liquid discharge head of the present embodiment, the cable portion 8 having the host device transmission wiring member 2b is provided so as to be separable from the head main body 7 having the liquid chamber portion 11, the cover member 4, and the heat radiating member 1.
FIG. 10 is a cross-sectional view showing a schematic configuration of the inside of the head main body 7 constituting the liquid discharge head of the present embodiment. FIG. 11 is an explanatory diagram showing the configuration of the heat radiating member 1 of the present embodiment.

As shown in FIG. 10, the heat radiating member 1 is arranged outside the cover member 4, the first heat radiating member 1a having a surface in contact with the outside air, and inside the cover member 4, and the drive control unit 3 It is composed of a second heat radiating member 1b having an end portion that comes into contact with the heat radiating member. In the present embodiment, the cover member 4 has a bent portion 42 that can come into contact with the end portion of the second heat radiating member 1b, and the second heat radiating between the bent portion 42 and the first heat radiating member 1a. The end portion of the member 1b is sandwiched.
The first heat radiating member 1a is formed of a plate-shaped portion, and is arranged so as to cover the side surface of the cover member 4 in the longitudinal direction as in the first embodiment described above.
With such a configuration, assembly becomes easy and assembling property is improved. Further, since only one surface of the first heat radiating member 1a is exposed to the outside and the surface in contact with the second heat radiating member 1b is not exposed, it is necessary to prevent deterioration of the appearance due to the adhesive squeezing out. Can be done.

The second heat radiating member 1b has a stepped structure having a width in the longitudinal direction different depending on the surface, one end of which is in contact with the drive control unit 3, and the other end of which is the inner surface of the bent portion 42 of the cover member 4 and the first. It is in contact with the heat radiating member 1a. Since the end of the second heat radiating member 1b is in contact with the drive control unit 3, the heat generated by the drive control unit 3 is transmitted to the second heat radiating member 1b and further has a surface in contact with the outside air. It is transmitted to the member 1a and efficiently dissipates heat.

(Fourth Embodiment)
A fourth embodiment of the present invention will be described with reference to FIGS. 12 and 13.
In the liquid discharge head of the present embodiment, the cable portion 8 having the host device transmission wiring member 2b is provided so as to be separable from the head main body 7 having the liquid chamber portion 11, the cover member 4, and the heat radiating member 1.
12A and 12B are schematic views showing a head main body 7 constituting the liquid discharge head of the present embodiment. FIG. 12A is a side view (side view in the lateral direction), and FIG. 12B is a front view of the main body (side surface in the longitudinal direction). (Fig.) And (C) are cross-sectional views showing a schematic internal configuration.
FIG. 13 is an explanatory diagram showing the configuration of the heat radiating member 1 of the present embodiment.

In the present embodiment, the heat radiating member 1 is arranged outside the cover member 4, has a surface in contact with the outside air, and is disposed inside the cover member 4, and is in contact with the drive control unit 3. Two sets (1A, 1B) of one-to-one set of heat-dissipating members 1 composed of a second heat-dissipating member 1b having contacting ends and the first heat-dissipating member 1a and the second heat-dissipating member 1b being in contact with each other. Two sets of heat radiating members 1A and 1B are thermally connected to each other.

As shown in FIG. 13B, the surface S1 of the first heat radiating member 1a comes into contact with the cover member 4 of the head body, and the surface S2 comes into contact with the outside air. As shown in FIG. 12A, the first heat radiating member 1a has a shape that covers a part of the side surface in the longitudinal direction and the side surface in the lateral direction of the cover member 4, so that the surface S1 and the cover member 4 The joint area becomes wider, and the sealing property can be further improved.
Further, the first heat radiating member 1a of the two sets of the heat radiating member 1A and 1B may be in direct contact with each other, but as shown in FIG. 12 (A), on the lateral side surface of the cover member 4 in the lateral direction. It is preferably connected by the connecting member 20.
Examples of the connecting member 20 include a fixing material having thermal conductivity (for example, an adhesive tape).

As shown in FIGS. 12C and 13A, since the first heat radiating member 1a is in contact with the second heat radiating member 1b, the first heat radiating member 1a of the heat radiating members 1A and 1B is in contact with each other. By doing so, the two sets of heat radiating members 1A and 1B are thermally connected to each other.
Since the end of the second heat radiating member 1b is in contact with the drive control unit 3, the heat generated by the drive control unit 3 is transmitted through the second heat radiating member 1b and is transmitted to the first heat radiating member 1a that is in contact with the second heat radiating member 1b. Further, it is also transmitted to the first heat radiating member 1a of the other heat radiating member.
In this way, in the present embodiment in which the two sets of heat radiating members 1A and 1B are thermally connected to each other, the temperatures of all the drive control units 3 (four in the present embodiment) can be made uniform.

(Fifth Embodiment)
A fifth embodiment of the present invention will be described with reference to FIGS. 14 and 15.
In the liquid discharge head of the present embodiment, the cable portion 8 having the host device transmission wiring member 2b is provided so as to be separable from the head main body 7 having the liquid chamber portion 11, the cover member 4, and the heat radiating member 1.
14A and 14B are schematic views showing a head main body 7 constituting the liquid discharge head of the present embodiment. FIG. 14A is a side view (side view in the lateral direction), and FIG. 14B is a front view of the main body (side surface in the longitudinal direction). (Fig.) And (C) are cross-sectional views showing a schematic internal configuration.
FIG. 15 is an explanatory diagram showing the configuration of the heat radiating member 1 of the present embodiment.

In the present embodiment, the heat radiating member 1 is arranged outside the cover member 4, has a surface in contact with the outside air, and is disposed inside the cover member 4, and is in contact with the drive control unit 3. It is composed of a second heat radiating member 1b having a contacting end portion, and the first heat radiating member 1a and the second heat radiating member 1b are in contact with each other. Then, two sets (1A, 1B) of one-to-one sets of heat-dissipating members 1 in which the first heat-dissipating member 1a and the second heat-dissipating member 1b are in contact with each other are provided, and the two sets of heat-dissipating members 1A and 1B cover the heat-dissipating members 1A and 1B. They are thermally connected to each other via the member 4.

As shown in FIG. 15B, the surface S1 of the first heat radiating member 1a is joined to the cover member 4 of the head body, and the surface S2 is in contact with the outside air.
As shown in FIGS. 14 (C) and 15 (A), the first heat radiating member 1a and the second heat radiating member 1b are in contact with each other on the contact surface, and the first heat radiating member 1a is a cover member. The second heat radiating member 1b is in contact with the outer surface of 4, and the second heat radiating member 1b is in contact with the open end of the cover member 4 at the tip of the contact surface with the first heat radiating member 1a. In this way, the two sets of heat radiating members 1A and 1B are thermally connected via the cover member 4.
Therefore, in the present embodiment, the temperatures of all the drive control units 3 (four in the present embodiment) can be made uniform as in the fourth embodiment described above.

[Liquid discharge unit]
The liquid discharge unit according to the present invention includes the above-mentioned liquid discharge head of the present invention.
17, 18 and 19 show an example of a liquid discharge unit in which the liquid discharge head of the present invention is mounted as an inkjet head.

The "liquid discharge unit" is a liquid discharge head integrated with other functional parts and mechanisms, and is an assembly of parts related to the function of discharging liquid. For example, the "liquid discharge unit" includes a combination of at least one of a head tank, a carriage, a supply mechanism, a maintenance / recovery mechanism, and a main scanning movement mechanism with a liquid discharge head.

Here, "integration" means, for example, a liquid discharge head and a functional component, a mechanism fixed to each other by fastening, adhesion, engagement, etc., or one in which one is movably held with respect to the other. Including. Further, the liquid discharge head, the functional parts, and the mechanism may be detachably attached to each other.

For example, as the liquid discharge unit 440, as shown in FIG. 17, the liquid discharge head 404 and the head tank 441 are integrated.
The liquid discharge unit 440 shown in FIG. 17 is mounted on the carriage 403. The carriage 403 is held by the guide member 401 that constitutes the main scanning movement mechanism, and reciprocates in the main scanning direction.
FIG. 17 shows a transport belt 412 which is a means for transporting a recording medium (for example, paper or the like) among the members constituting the device for discharging the liquid described later. The transport belt 412 is an endless belt, and is hung between the transport roller 413 and the tension roller 414.

In addition, there are cases in which the liquid discharge head and the head tank 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 head tank of these liquid discharge units and the liquid discharge head.

Further, as a liquid discharge unit, there is a liquid discharge head and a carriage integrated.

Further, as a liquid discharge unit, the liquid discharge head 404 is movably held by a guide member 401 forming a part of the main scanning movement mechanism, and the liquid discharge head 404 and the main scanning movement mechanism 493 are integrated. There is. Further, as shown in FIG. 18, there is a case in which the liquid discharge head 404, the carriage 403, and the main scanning moving mechanism 493 are integrated.
The liquid discharge unit 440 shown in FIG. 18 includes a housing portion composed of side plates 491A, 491B and a back plate 491C, a main scanning movement mechanism 493, and members constituting a device for discharging liquid, which will be described later. It is composed of a carriage 403 and a liquid discharge head 404. Arrow D1 in the figure indicates the main scanning direction.

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, as shown in FIG. 19, a tube 456 is connected to a liquid discharge head 404 to which a flow path component 444 is attached, and the liquid discharge head 404 and a supply mechanism are integrated. The liquid of the liquid storage source is supplied to the liquid discharge head 404 via the tube 456.
The flow path component 444 is arranged inside the cover 442. A head tank 441 may be included instead of the flow path component 444. Further, a connector 443 that electrically connects to the liquid discharge head 404 is provided on the upper part of the flow path component 444.

The main scanning movement mechanism shall also include a single guide member. Further, the supply mechanism includes a single tube and a single loading unit.

[Device for discharging liquid]
The device for discharging the liquid according to the present invention includes the above-mentioned liquid discharge head of the present invention.
Space saving can be realized by providing a liquid discharge head that can achieve both excellent assembly performance and excellent heat dissipation efficiency and can increase the maximum discharge amount, and the device that discharges liquid can be downsized. It is possible to realize low cost and prevent malfunction due to temperature rise, and to realize stable liquid discharge.

In the present application, 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 toward the air or the liquid.

The "device for discharging the liquid" may include means for feeding, transporting, and discharging paper to which the liquid can be attached, as well as a pretreatment device, a posttreatment device, and the like.

For example, as a "device that ejects a liquid", an image forming apparatus that ejects ink to form an image on paper, and a powder is formed in layers in order to form a three-dimensional object (three-dimensional object). 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 "material to which a liquid can adhere" means a material to which a liquid can adhere at least temporarily, such as one that adheres and adheres, and one that adheres and permeates. Specific examples include paper, recording paper, recording paper, film, recording 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, including anything to which the liquid adheres, unless otherwise specified.

The material of the above-mentioned "material to which liquid can be attached" may be paper, thread, fiber, cloth, leather, metal, plastic, glass, wood, ceramics or the like as long as the liquid can be attached 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 to have. More specifically, solvents such as water and organic solvents, colorants such as dyes and pigments, polymerizable compounds, resins, functionalizing materials such as surfactants, biocompatible materials such as DNA, amino acids and proteins, and calcium. , Solvents, suspensions, emulsions, etc. containing edible materials such as natural pigments, etc., for example, inks for inkjets, surface treatment liquids, constituents of electronic elements and light emitting elements, and formation of electronic circuit resist patterns. It can be used for applications such as a liquid for use and a material liquid 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", a treatment liquid coating device for ejecting a 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, raw materials. There is an injection granulation device that granulates fine particles of raw materials by injecting a composition liquid in which the above-mentioned material is dispersed in a solution through a nozzle.

FIG. 16 shows an example of an inkjet image forming apparatus which is an apparatus for ejecting a liquid equipped with the liquid ejection head of the present invention as an inkjet head.
16 (A) is a perspective view showing an outline of a main part configuration, and FIG. 16 (B) is a side view.

The inkjet image forming apparatus 301 includes a carriage that can move in the main scanning direction, a recording head including an inkjet head mounted on the carriage, an ink cartridge that supplies ink to the recording head, and the like. The unit is housed in the printing mechanism unit 302. A paper cassette (paper tray) 304 capable of loading a large number of recording papers 303 can be freely inserted and removed from the lower part of the main body of the apparatus, and the recording paper 303 is manually fed. The manual feed tray 305 can be opened and closed, the recording paper 303 supplied from the paper feed cassette 304 or the manual feed tray 305 is taken in, the required image is recorded by the printing mechanism 302, and then the paper feed tray 305 is mounted on the rear surface side. Paper is ejected to the output tray 306.

The printing mechanism unit 302 slidably holds the carriage 313 in the main scanning direction (vertical direction of the paper surface) by the main guide rods 311 and the slave guide rods 312, which are guide members laid horizontally on the left and right side plates (not shown). The carriage 313 has a recording head 314 composed of an inkjet head that ejects ink droplets of each color of yellow (Y), cyan (C), magenta (M), and black (B), and has a plurality of ink ejection ports as main scanning directions. They are arranged in the crossing direction and are mounted with the ink droplet ejection direction facing downward. Further, the carriage 313 is replaceably mounted with each ink cartridge 315 for supplying ink of each color to the recording head 314.

The ink cartridge 315 has an air port that communicates with the atmosphere above, a supply port that supplies ink to the inkjet head below, and a porous body filled with ink inside, and the capillary force of the porous body. Keeps the ink supplied to the inkjet head at a slight negative pressure.

Further, although the recording head 314 of each color is used as the recording head here, one head having a nozzle for ejecting ink droplets of each color may be used. Further, the inkjet head used as the recording head 314 is a piezo type that pressurizes ink through a vibrating plate that forms a liquid chamber wall surface with an electromechanical conversion element such as a piezoelectric element, or a piezo type that generates bubbles by a heat generating resistor to generate ink. A bubble type that pressurizes the ink, or an electrostatic type that pressurizes the ink by displaced the vibrating plate by the electrostatic force between the vibrating plate forming the wall surface of the ink flow path and the electrode facing the vibrating plate can be used. In this embodiment, an electrostatic inkjet head is used.

Here, the carriage 313 is slidably fitted on the main guide rod 311 on the rear side (downstream side in the paper transport direction), and slidably mounted on the slave guide rod 312 on the front side (downstream side in the paper transport direction). doing. Then, in order to move and scan the carriage 313 in the main scanning direction, a timing belt 320 is stretched between the drive pulley 318 and the driven pulley 319 which are rotationally driven by the main scanning motor 317, and the timing belt 320 is mounted on the carriage 313. The carriage 313 is reciprocated by the forward and reverse rotation of the main scanning motor 317.

On the other hand, in order to convey the recording paper 303 set in the paper feed cassette 304 to the lower side of the recording head 314, the paper feed roller 321 and the friction pad 322 that separately supply the recording paper 303 from the paper feed cassette 304, and the recording paper. A guide member 323 for guiding 303, a transport roller 324 for reversing and transporting the fed recording paper 303, and a transport roller 325 pressed against the peripheral surface of the transport roller 324 and a recording paper 303 from the transport roller 324. A tip roller 326 that defines the delivery angle is provided. The transfer roller 324 is rotationally driven by the sub-scanning motor 327 via the gear train.

Then, a printing receiving member 329, which is a paper guide member, is provided to guide the recording paper 303 sent out from the transport roller 324 on the lower side of the recording head 314 corresponding to the moving range of the carriage 313 in the main scanning direction. On the downstream side of the imprint receiving member 329 in the paper transport direction, a transport roller 331 and a spur 332 that are rotationally driven to feed the recording paper 303 in the paper discharge direction are provided, and the recording paper 303 is further fed to the paper discharge tray 306. A paper ejection roller 333 and a spur 334, and guide members 335 and 336 forming a paper ejection path are arranged.

At the time of recording, by driving the recording head 314 in response to the image signal while moving the carriage 313, ink is ejected to the stopped recording paper 303 to record one line, and the recording paper 303 is conveyed by a predetermined amount. Record the next line. When the recording end signal or the signal that the rear end of the recording paper 303 reaches the recording area is received, the recording operation is ended and the recording paper 303 is ejected.

Further, a recovery device 337 for recovering the ejection defect of the recording head 314 is arranged at a position outside the recording area on the right end side in the moving direction of the carriage 313. The recovery device has a cap means, a suction means, and a cleaning means. The carriage 313 is moved to the recovery device 337 side during the printing standby, and the recording head 314 is capped by the capping means, and the ejection port portion is kept in a wet state to prevent ejection defects due to ink drying. In addition, by ejecting ink that is not related to recording during recording, the ink viscosities of all the ejection ports are kept constant, and stable ejection performance is maintained.

When a discharge defect occurs, the discharge port of the recording head 314 is sealed by a capping means, air bubbles, etc. are sucked out from the discharge port by a suction means through a tube, and ink, dust, etc. adhering to the discharge port surface are cleaned. It is removed by means and the discharge defect is recovered. Further, the sucked ink is discharged to a waste ink reservoir (not shown) installed in the lower part of the main body, and is absorbed and held by an ink absorber inside the waste ink reservoir.

1 Heat dissipation member 1a First heat dissipation member 1b Second heat dissipation member 2 Wiring member 2a Relay wiring member 2b Upper device transmission wiring member 3 Drive control unit 4 Cover member 5 Connector board 6 Connector 7 Head body 8 Head cable unit 10 Pressure generation Element 11 Liquid chamber 12 Housing 13 Filter plate 14 Manifold 15 Vibrating plate 16 Restrictor plate 17 orifice plate 401 Guide member 403 Carriage 404 Liquid discharge head 405 Main scanning motor 406 Drive pulley 407 Driven pulley 408 Timing belt 412 Transfer belt 413 Transfer roller 414 Tension roller 440 Liquid discharge unit 441 Head tank 442 Cover 443 Connector 444 Flow path parts 456 Tubes 491A, 491B Side plates 491C Back plate 493 Main scanning movement mechanism

Japanese Patent No. 4186883

Claims (9)

In the liquid discharge head that applies pressure to the liquid in the pressure chamber by driving the pressure generating element and discharges the liquid from the nozzle.
A drive control unit that controls the drive of the pressure generating element and
The heat radiating member in contact with the drive control unit and
A first heat radiating member having a drive control unit and a cover member covering a part of the heat radiating member, the heat radiating member being arranged outside the cover member and having a surface in contact with the outside air, and the cover. disposed inside the member consists of a second heat radiation member having the drive control section abutting ends, Ri Na in said first heat radiating member and the second heat radiating member are in contact with each other,
The cover member has a bent portion that can come into contact with the end portion of the second heat radiating member, and sandwiches the end portion of the second heat radiating member between the bent portion and the first heat radiating member. a liquid discharge head, wherein to Rukoto. The liquid discharge head according to claim 1, wherein a wiring member that transmits a signal to the drive control unit is provided so as to be separable from the head body having the heat radiation member. Claim 1 or 2 characterized in that at least one of the first heat radiating member and the second heat radiating member has an engaging portion having an L-shaped cross section and comes into contact with the engaging portion via the engaging portion. The liquid discharge head described in. The liquid discharge head according to any one of claims 1 to 3, wherein the first heat radiating member is arranged so as to cover a side surface of the cover member in the longitudinal direction. Two sets of the one-to-one set of the heat radiating members in which the first heat radiating member and the second heat radiating member are in contact with each other are provided.
The liquid discharge head according to any one of claims 1 to 4 , wherein the two sets of the heat radiating members are thermally connected to each other. The liquid discharge head according to claim 5 , wherein the two sets of the heat radiating members are in contact with each other. A liquid discharge unit comprising a plurality of liquid discharge heads according to any one of claims 1 to 6. A device for discharging a liquid, which comprises the liquid discharge head according to any one of claims 1 to 6. In the liquid discharge head that applies pressure to the liquid in the pressure chamber by driving the pressure generating element and discharges the liquid from the nozzle.
A drive control unit that controls the drive of the pressure generating element and
The heat radiating member in contact with the drive control unit and
It has a drive control unit and a cover member that covers a part of the heat dissipation member.
The heat radiating member has a first heat radiating member arranged outside the cover member and having a surface in contact with the outside air, and an end portion arranged inside the cover member and in contact with the drive control unit. It is composed of two heat-dissipating members, and the first heat-dissipating member and the second heat-dissipating member are in contact with each other.
The second heat radiating member extends from the drive control unit in a direction opposite to the liquid discharge direction to the cover member so as to form a gap between the second heat radiating member and the cover member. A liquid discharge head characterized by having a stretchable portion.

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