JP2019217757A - Liquid jet head and liquid jet device - Google Patents

Abstract

To suppress rise in internal temperature of a head unit.SOLUTION: A liquid jet head includes: a first head unit and a second head unit including a liquid jet part for jetting liquid from a nozzle and a drive circuit for driving the liquid jet part; a first individual heat radiation body thermally connected to the drive circuit of the first head unit; a second individual heat radiation body thermally connected to the drive circuit of the second head unit; and a common heat radiation body thermally connected to the first individual heat radiation body and the second individual heat radiation body.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a technique for ejecting a liquid such as ink.

  For example, Patent Literature 1 discloses a liquid ejecting head that ejects a liquid such as ink from a plurality of nozzles. A drive IC for driving a piezoelectric element for discharging ink from the nozzle is mounted on the liquid discharge head.

JP-A-2006-000488

  In the technique of Patent Document 1, the driving IC generates heat due to the driving of the piezoelectric element, and the temperature of the inside of the liquid ejection head rises, so that the viscosity of the ink changes. Therefore, there is a problem that an error occurs in the ink ejection characteristics.

  In order to solve the above problems, a liquid ejecting head according to a preferred aspect of the present invention includes a first head unit including a liquid ejecting unit that ejects liquid from a nozzle, and a drive circuit that drives the liquid ejecting unit. A second head unit, a first individual radiator thermally connected to a drive circuit of the first head unit, and a second individual radiator thermally connected to a drive circuit of the second head unit; A common radiator thermally connected to the first individual radiator and the second individual radiator.

FIG. 1 is a block diagram illustrating a configuration of a liquid ejecting apparatus according to a first embodiment of the present invention. FIG. 3 is an exploded perspective view of a head unit. FIG. 3 is a sectional view of the head unit (a sectional view taken along line III-III in FIG. 2). FIG. 4 is a sectional view of the liquid jet head (a sectional view taken along line IV-IV in FIG. 1). FIG. 6 is a cross-sectional view of a liquid jet head according to a second embodiment. It is sectional drawing of the head unit which concerns on 3rd Embodiment. FIG. 9 is a cross-sectional view of a liquid jet head according to a modification.

<First embodiment>
FIG. 1 is a configuration diagram illustrating a liquid ejecting apparatus 100 according to the first embodiment of the present invention. The liquid ejecting apparatus 100 according to the first embodiment is an ink jet printing apparatus that ejects ink, which is an example of a liquid, onto a medium 12. The medium 12 is typically printing paper, but an object to be printed of any material such as a resin film or cloth is used as the medium 12. As illustrated in FIG. 1, the liquid ejecting apparatus 100 is provided with a liquid container 14 for storing ink. For example, a cartridge that can be attached to and detached from the liquid ejecting apparatus 100, a bag-shaped ink pack formed of a flexible film, or an ink tank that can refill ink is used as the liquid container 14. A plurality of types of inks having different colors are stored in the liquid container 14.

  As illustrated in FIG. 1, the liquid ejecting apparatus 100 includes a control unit 20, a transport mechanism 22, a liquid ejecting head 26, and a housing 28. The control unit 20, the transport mechanism 22, and the liquid ejecting head 26 are housed in a housing 28. The control unit 20 includes, for example, a processing circuit such as a CPU (Central Processing Unit) or an FPGA (Field Programmable Gate Array) and a storage circuit such as a semiconductor memory, and integrally controls each element of the liquid ejecting apparatus 100. The control unit 20 is an example of a control unit. The transport mechanism 22 transports the medium 12 in the Y direction under the control of the control unit 20.

  The liquid jet head 26 includes a plurality of head units 261. The liquid jet head 26 of the first embodiment is a line head in which a plurality of head units 261 are arranged along an X direction orthogonal to a Y direction. For example, a plurality of head units 261 are arranged in a staggered or staggered arrangement. Each head unit 261 ejects the ink supplied from the liquid container 14 to the medium 12 under the control of the control unit 20. A desired image is formed on the surface of the medium 12 by each head unit 261 ejecting ink onto the medium 12 in parallel with the transport of the medium 12 by the transport mechanism 22. Note that a direction perpendicular to the XY plane parallel to the surface of the medium 12 is hereinafter referred to as a Z direction. The direction of ink ejection by each head unit 261 corresponds to the Z direction. The Z direction is typically a vertical direction.

  FIG. 2 is an exploded perspective view of the head unit 261. FIG. 3 is a cross-sectional view taken along line III-III in FIG. As illustrated in FIG. 2, the head unit 261 includes a plurality of nozzles N arranged in the Y direction. The plurality of nozzles N of the first embodiment are divided into a first row L1 and a second row L2, which are arranged side by side at intervals in the X direction. Each of the first row L1 and the second row L2 is a set of a plurality of nozzles N arranged linearly in the Y direction. Note that the positions of the nozzles N in the Y direction can be different between the first row L1 and the second row L2 (that is, staggered or staggered), but the first row L1 and the second row L2. Hereinafter, a configuration in which the positions of the nozzles N in the Y direction are made to coincide with each other will be exemplified below for convenience. As can be understood from FIG. 3, the head unit 261 of the first embodiment has the elements related to the nozzles N in the first row L1 and the elements related to the nozzles N in the second row L2 arranged substantially line-symmetrically. It is the structure which was done.

  As illustrated in FIGS. 2 and 3, each head unit 261 includes a liquid ejecting unit 50 that ejects ink from the nozzles N, a driving circuit 80 that drives the liquid ejecting unit 50, and a housing that is used for storing ink. And a body 48.

  The liquid ejecting unit 50 electrically connects the flow path structure 30 in which the pressure chamber 342 communicating with the nozzle N is formed, the piezoelectric element 44 that changes the pressure of the pressure chamber 342, the drive circuit 80, and the piezoelectric element 44. It includes a first wiring board 46 on which wiring to be connected is formed, and a second wiring board 47 joined to the first wiring board 46. The piezoelectric element 44 is an example of a driving element.

  The flow channel structure 30 is a structure that forms a flow channel for supplying ink to the plurality of nozzles N. The channel structure 30 according to the first embodiment includes a channel substrate 32, a pressure chamber substrate 34, a vibration plate 42, a nozzle plate 62, and a first vibration absorber 64. Each member constituting the flow path structure 30 is a plate-like member that is long in the X direction. The housing 48 and the pressure chamber substrate 34 are provided on the surface of the flow path substrate 32 on the negative side in the Z direction. On the other hand, the nozzle plate 62 and the first vibration absorber 64 are provided on the surface of the flow path substrate 32 on the positive side in the Z direction. For example, each member is fixed by an adhesive.

  The nozzle plate 62 is a plate-like member on which a plurality of nozzles N are formed. Each of the plurality of nozzles N is a circular through hole through which ink passes. In the nozzle plate 62 of the first embodiment, a plurality of nozzles N constituting a first row L1 and a plurality of nozzles N constituting a second row L2 are formed. For example, the nozzle plate 62 is manufactured by processing a single crystal substrate of silicon (Si) using a semiconductor manufacturing technology (for example, a processing technology such as dry etching or wet etching). However, a known material and a known manufacturing method can be arbitrarily adopted for manufacturing the nozzle plate 62.

  As illustrated in FIGS. 2 and 3, the flow path substrate 32 is connected to the opening 320, the plurality of supply flow paths 322, and the plurality of communication flow paths 324 for each of the first row L1 and the second row L2. A channel 326 is formed. The opening 320 is an elongated opening along the X direction in a plan view (that is, as viewed from the Z direction), and the supply flow path 322 and the communication flow path 324 are through holes formed for each nozzle N. is there. The connection flow path 326 is a space formed in an elongated shape along the X direction over the plurality of nozzles N, and allows the opening 320 and the plurality of supply flow paths 322 to communicate with each other. Each of the plurality of communication channels 324 overlaps one nozzle N corresponding to the communication channel 324 in plan view.

  As illustrated in FIGS. 2 and 3, the pressure chamber substrate 34 is a plate-like member in which a plurality of pressure chambers 342 are formed for each of the first row L1 and the second row L2. The plurality of pressure chambers 342 are arranged in the X direction. Each pressure chamber 342 (cavity) is a long space that is formed for each nozzle N and extends in the Y direction in plan view. The channel substrate 32 and the pressure chamber substrate 34 are manufactured by processing a silicon single crystal substrate using, for example, a semiconductor manufacturing technique, similarly to the nozzle plate 62 described above. However, known materials and manufacturing methods can be arbitrarily adopted for manufacturing the flow path substrate 32 and the pressure chamber substrate 34.

  As illustrated in FIG. 2, a vibration plate 42 is formed on the surface of the pressure chamber substrate 34 opposite to the flow path substrate 32. The vibration plate 42 of the first embodiment is a plate-like member that can elastically vibrate. By selectively removing a part of the plate member having a predetermined thickness in a region corresponding to the pressure chamber 342 in the thickness direction, a part or all of the vibration plate 42 is integrated with the pressure chamber substrate 34. May be formed.

  As understood from FIG. 3, the pressure chamber 342 is a space located between the flow path substrate 32 and the vibration plate 42. A plurality of pressure chambers 342 are arranged in the X direction for each of the first row L1 and the second row L2. As illustrated in FIGS. 2 and 3, the pressure chamber 342 communicates with the communication channel 324 and the supply channel 322. Therefore, the pressure chamber 342 communicates with the nozzle N through the communication channel 324 and communicates with the opening 320 through the supply channel 322 and the connection channel 326.

  As illustrated in FIGS. 2 and 3, the piezoelectric element 44 is located on the surface of the flow channel structure 30 opposite to the nozzle N. Specifically, on the surface of the vibration plate 42 of the flow channel structure 30 opposite to the pressure chamber 342, a plurality of nozzles N corresponding to different nozzles N are provided for each of the first row L1 and the second row L2. The piezoelectric element 44 is formed. Each piezoelectric element 44 is a passive element that changes the pressure of the pressure chamber 342 by being deformed by a drive signal supplied from the drive circuit 80. The drive signal output from the drive circuit 80 is supplied to each piezoelectric element 44 via the connection terminal T of the first wiring board 46. The drive signal is a signal for driving the piezoelectric element 44.

  The first wiring substrate 46 in FIG. 2 is a plate-like member that faces the surface of the vibration plate 42 on which the plurality of piezoelectric elements 44 are formed at an interval. That is, the first wiring board 46 is located on the opposite side of the flow path structure 30 from the piezoelectric element 44. Wiring for electrically connecting the drive circuit 80 and the piezoelectric element 44 is formed on the first wiring board 46. The first wiring board 46 of the first embodiment also functions as a reinforcing plate for reinforcing the mechanical strength of the head unit 261 and a sealing plate for protecting and sealing the piezoelectric element 44.

  The first wiring board 46 is electrically connected to the control unit 20 via the second wiring board 47. The second wiring board 47 is a flexible wiring board for supplying a drive signal from the control unit 20 to the first wiring board 46. The end of the second wiring board 47 is joined to the first wiring board 46. In FIG. 2, the positive end of the second wiring board 47 in the X direction is joined to the negative end of the first wiring board 46 in the X direction. For example, a connection component such as FPC (Flexible Printed Circuits) or FFC (Flexible Flat Cable) is suitably adopted as the second wiring board 47.

  The container 48 is a case for storing ink supplied to the plurality of pressure chambers 342. The surface on the positive side in the Z direction of the container 48 is joined to the flow path substrate 32 with, for example, an adhesive. Specifically, the container 48 is a structure in which a liquid storage chamber (reservoir) R that is long in the X direction in plan view is formed. In the first embodiment, a liquid storage chamber R is formed for each of the first row L1 and the second row L2. As illustrated in FIG. 3, the liquid storage chamber R includes a first space R1 along the Y direction and a second space R2 along the Z direction in a sectional view. The first space R1 of the liquid storage chamber R overlaps the piezoelectric element 44 in plan view. The second space R2 of the liquid storage chamber R and the opening 320 of the flow path substrate 32 communicate with each other. Ink is supplied to the liquid storage chamber R via an inlet 482 formed in the container 48. The introduction port 482 is a tubular portion that allows the liquid storage chamber R of the container 48 to communicate with the outside of the container 48. The ink in the liquid storage chamber R is supplied to the pressure chamber 342 via the connection flow path 326 and each supply flow path 322. The container 48 is formed by, for example, injection molding of a resin material.

  An opening 484 is formed in the container 48 of the first embodiment. The opening 484 is an opening that is formed to be long in the X direction so as to overlap the liquid storage chamber R. As illustrated in FIGS. 2 and 3, a second vibration absorber 486 is provided on the upper surface of the housing 48. The second vibration absorber 486 is a flexible film that functions as a compliance substrate that absorbs pressure fluctuations of the ink in the liquid storage chamber R, and is installed on the upper surface of the container 48 so as to close the opening 484. A wall surface (specifically, a ceiling surface) of the liquid storage chamber R is configured.

  As illustrated in FIG. 3, the first vibration absorber 64 is an element for absorbing pressure fluctuation of the ink in the liquid storage chamber R. The first vibration absorber 64 of the first embodiment includes an elastic film 641 and a support plate 643. The elastic film 641 is a flexible member formed in a film shape. The elastic film 641 of the first embodiment is provided on the surface of the flow path substrate 32 so as to close the opening 320, the supply flow path 322, and the connection flow path 326. The support plate 643 is a flat plate made of a highly rigid material such as stainless steel, and the elastic film 641 is placed on the surface of the flow path substrate 32 so that the opening formed in the flow path substrate 32 is closed by the elastic film 641. To support. When the elastic film 641 is deformed in accordance with the pressure of the ink in the storage chamber R, the pressure fluctuation in the liquid storage chamber R is suppressed.

  As illustrated in FIG. 2, the first wiring board 46 includes a base part 70 and a plurality of wirings 72 connected to the driving circuit 80. The base 70 is an insulating plate-like member that is long in the X direction, and is located between the flow path structure 30 and the drive circuit 80. The base portion 70 is manufactured by processing a silicon single crystal substrate using, for example, a semiconductor manufacturing technique. However, a known material or manufacturing method can be arbitrarily adopted for manufacturing the base portion 70. The wiring 72 transmits, for example, a drive signal. A plurality of wirings 72 are located at the end of the first surface F1 of the base portion 70 on the negative side in the X direction.

  The base portion 70 includes a first surface F1 and a second surface F2 located on opposite sides of each other. For example, an adhesive is applied to a surface of the pressure chamber substrate 34 or the vibration plate 42 opposite to the flow path substrate 32. Fixed using. Specifically, the base portion 70 is installed such that the second surface F2 faces the surface of the vibration plate 42 with an interval.

  As illustrated in FIG. 2, the drive circuit 80 and the second wiring board 47 are mounted on the first surface F1 of the base part 70. That is, the drive circuit 80 and the second wiring board 47 are mounted on the surface of the first wiring board 46 opposite to the flow path structure 30. The drive circuit 80 is a long IC chip along the longitudinal direction (X direction) of the base unit 70. The second wiring board 47 is mounted on the negative end in the X direction of the first surface F1 of the base portion 70. On the second wiring board 47, for example, a plurality of wirings for transmitting a drive signal to the first wiring board 46 are formed. The plurality of wirings 72 of the first wiring board 46 and the plurality of wirings of the second wiring board 47 are electrically connected. The driving circuit 80 generates heat by the operation of driving the piezoelectric element 44.

As illustrated in FIGS. 2 and 3, an individual heat radiator 90 is arranged on the surface of the drive circuit 80 opposite to the first wiring board 46. That is, the individual radiator 90 is located on the side opposite to the nozzle N when viewed from the drive circuit 80. The individual heat radiator 90 and the portion of the housing 48 that forms the bottom surface of the first space R1 face each other with a space therebetween. The individual radiator 90 is formed of, for example, a material having a thermal conductivity of 10 W · m ⁻¹ · K ⁻¹ or more. For example, a thin plate of a metal such as aluminum or copper is suitable as the individual radiator 90. The individual heat radiator 90 of the embodiment is formed in a long shape along the longitudinal direction (X direction) of the drive circuit 80 so as to face the surface of the drive circuit 80. Specifically, individual heat radiators 90 are formed so as to overlap over the entire drive circuit 80. That is, the individual radiators 90 are longer in the X and Y directions than the drive circuit 80. The drive circuit 80 is arranged in the space formed by the container 48.

The individual radiator 90 and the drive circuit 80 are joined by, for example, an adhesive. Therefore, the heat generated in the drive circuit 80 is diffused to the individual radiator 90. That is, the individual radiator 90 and the drive circuit 80 are thermally connected. Note that the element A and the element B “thermally connect”
(1) a state in which the element A and the element B are in direct contact, or
(2) An element C having a thermal conductivity of 10 W · m ⁻¹ · K ⁻¹ or more is interposed between the element A and the element B, and a gap existing between the element A and the element B is 50 μm. It means the following state.
The “gap” means a portion between the element A and the element B whose thermal conductivity is less than 10 W · m ⁻¹ · K ⁻¹ , and is typically a space (that is, an air space).
As understood from the above description, the relationship between the individual radiator 90 and the drive circuit 80 in the first embodiment is in the state (2) where the adhesive is the element C.

  FIG. 4 is a sectional view taken along line IV-IV in FIG. 1 (a sectional view of the liquid ejecting head 26). As illustrated in FIG. 4, the liquid ejecting head 26 includes, in addition to the plurality of head units 261, a fixing plate 263 to which the plurality of head units 261 are fixed, and a common radiator 265 facing the fixing plate 263. I do. The common radiator 265 and the fixed plate 263 are flat members extending in the X direction. A plurality of head units 261 are located between the fixing plate 263 and the common radiator 265. The fixed plate 263 and the common radiator 265 are continuous over the plurality of head units 261. That is, the individual heat radiators 90 are individually installed for each head unit 261, whereas the common heat radiator 265 is commonly installed over a plurality of head units 261.

The common radiator 265 is formed of, for example, a material having a thermal conductivity of 10 W · m ⁻¹ · K ⁻¹ or more. For example, a thin plate of a metal such as aluminum or copper is used as the common radiator 265. However, it is desirable that the thermal conductivity of the common radiator 265 be higher than the thermal conductivity of the individual radiator 90.

  For example, the fixed plate 263 is formed of a highly rigid metal such as stainless steel. A portion on the nozzle side (that is, the positive side in the Z direction) of each head unit 261 contacts the fixing plate 263. That is, the flow path structure 30 of the head unit 261 contacts the fixing plate 263. Each head unit 261 is joined to the fixing plate 263 by, for example, an adhesive in which metal particles are dispersed. As illustrated in FIG. 4, an opening O is formed in the fixed plate 263 so as to correspond to the outer shape of the nozzle plate 62. Therefore, the nozzle N is exposed from the opening O.

  The individual radiator 90 of each head unit 261 is thermally connected to the drive circuit 80 of the head unit 261 and the common radiator 265. As illustrated in FIG. 4, the individual heat radiator 90 of the first embodiment faces the surface of the drive circuit 80 corresponding to the individual heat radiator 90, and has an end in the longitudinal direction (ie, the X direction) of the drive circuit 80. Is thermally connected to the common radiator 265. The common radiator 265 is located on the opposite side of the drive circuit 80 of the head unit 261 from the individual radiator 90 of the head unit 261. Specifically, the individual heat radiator 90 includes a first portion 91, a second portion 92, and a third portion 93.

  The first portion 91 is a portion of the individual radiator 90 that contacts the drive circuit 80. The first portion 91 of the first embodiment is arranged to face the drive circuit 80. The first portion 91 contacts the surface of the drive circuit 80 on the side opposite to the first wiring board 46. The end of the first portion 91 on the negative side in the X direction extends from the space inside the housing 48 to the outside. The second portion 92 is a portion of the first portion 91 extending from the end on the negative side in the X direction toward the common heat radiator 265. The third portion 93 is a portion of the individual radiator 90 that contacts the common radiator 265. The third portion 93 of the first embodiment extends from the end of the second portion 92 on the negative side in the Z direction toward the positive side in the X direction. As illustrated in FIG. 4, the third portion 93 is located between the common radiator 265 and the container 48. The third portion 93 contacts the surface of the common heat radiator 265 on the head unit 261 side. As understood from the above description, the common radiator 265 and the individual radiator 90 are thermally connected to each other at the negative end of the drive circuit 80 in the X direction.

  The heat generated in each drive circuit 80 propagates to the common radiator 265 via the individual radiator 90 thermally connected to the drive circuit 80. That is, the plurality of individual radiators 90 are thermally connected to the common radiator 265 in common. In the first embodiment, the housing 28 in which the liquid ejecting head 26 is housed is thermally connected to the common radiator 265.

  The inlet 482 of the housing 48 is inserted into a through hole H1 formed in the common heat radiator 265. That is, the ink passes through the inside of the common radiator 265. The second wiring board 47 joined to the first wiring board 46 is inserted into a through hole H2 formed in the common heat radiator 265. As illustrated in FIG. 4, the second portion 92 of the individual heat dissipator 90 contacts a portion of the second wiring board 47 along the Y direction. Specifically, the second wiring board 47 contacts the surface of the second portion 92 of the individual heat radiator 90 opposite to the surface of the housing 48. That is, the second portion 92 is located between the container 48 and the second wiring board 47. Therefore, the heat of the second wiring board 47 propagates to the individual radiator 90. That is, in the first embodiment, the individual radiator 90 is thermally connected to the second wiring board 47.

  As understood from the above description, in the first embodiment, since the heat generated in the drive circuit 80 is radiated through the individual radiator 90 and the common radiator 265, only the individual radiator 90 is provided, for example. The area available for heat dissipation can be increased as compared with the configuration. Therefore, a rise in the temperature inside the head unit 261 can be efficiently suppressed. As a result, it is possible to reduce an error in the ink ejection characteristics due to a rise in the temperature inside the head unit 261.

  In the first embodiment, each individual radiator 90 is located on the side opposite to the nozzle N when viewed from the drive circuit 80, and the common radiator 265 is located on the opposite side to the drive circuit 80 when viewed from the individual radiator 90. Therefore, for example, the common radiator 265 can be easily mounted on the liquid ejecting head 26 as compared with a configuration in which the common radiator 265 is located on the drive circuit 80 side as viewed from each individual radiator 90.

  In the first embodiment, since the individual radiator 90 of each head unit 261 is thermally connected to the second wiring board 47 of the head unit 261, there is an advantage that heat generated in the second wiring board 47 can also be radiated. is there. Further, in the first embodiment, since the housing 28 and the common radiator 265 are thermally connected, the heat of the head unit 261 can be radiated through the housing 28. Note that it is not essential in the first embodiment that the second wiring board 47 is thermally connected to the individual radiator 90 and that the housing 28 is thermally connected to the common radiator 265.

  In the configuration of the first embodiment in which the drive circuit 80 is mounted on the surface of the first wiring board 46 opposite to the flow path structure 30, the drive circuit 80 is disposed in the space formed by the housing 48. Is done. That is, heat generated in the drive circuit 80 tends to stay inside the head unit 261. Therefore, a configuration in which the heat of the drive circuit 80 is radiated by the individual radiator 90 and the common radiator 265 is more effective.

  In the first embodiment, a specific head unit 261 of the plurality of head units 261 can be referred to as a first head unit, and a head unit 261 different from the first head unit can be referred to as a second head unit. In the first embodiment, a first individual radiator thermally connected to the drive circuit 80 of the first head unit and a second individual radiator thermally connected to the drive circuit 80 of the second head unit are provided. This is the configuration provided. Then, the common radiator 265 is thermally connected to the first individual radiator and the second individual radiator.

  According to the configuration of the first embodiment in which the fixing plate 263 is formed of metal, heat generated in the drive circuit 80 can be efficiently radiated from the fixing plate 263. In the first embodiment, since each head unit 261 is connected to the fixing plate 263 by the adhesive in which the metal particles are dispersed, there is an advantage that the heat of each head unit 261 is easily transmitted to the fixing plate 263. Further, according to the configuration of the first embodiment in which the ink passes through the inside of the common heat radiator 265, the heat generated in the head unit can be efficiently radiated through the ink.

<Second embodiment>
A second embodiment of the present invention will be described. In the following examples, the same reference numerals are used for elements having the same functions as those in the first embodiment, and detailed descriptions thereof will be appropriately omitted.

  FIG. 5 is a cross-sectional view of the liquid jet head 26 according to the second embodiment. The liquid ejecting head according to the second embodiment has a configuration in which a wall portion 267 is added to the liquid ejecting head 26 according to the first embodiment. As illustrated in FIG. 5, the wall 267 is formed from the common radiator 265 to the fixing plate 263. That is, the end of the wall 265 on the negative side in the Z direction abuts on the fixing plate 263. The wall 267 is located between two head units 261 adjacent to each other. In the second embodiment, the wall 267 is formed integrally with the common heat radiator 265. Similarly to the common radiator 265, the wall portion 267 is formed of a metal such as aluminum or copper. Note that the common radiator 265 and the wall 267 may be formed separately.

  In the second embodiment, the same effects as in the first embodiment are realized. In the second embodiment, since the wall portion 267 is formed between two head units 261 adjacent to each other, there is an advantage that heat of one head unit 261 is not easily transmitted to the other head unit 261. Further, since the wall portion 267 is formed of metal, heat generated in the head unit 261 can be easily transmitted to the common radiator 265 via the wall portion 267. In the second embodiment, the ink may pass through the inside of the wall portion 267. According to the above configuration, there is an advantage that the heat generated in the head unit 261 can be efficiently radiated through the ink.

<Third embodiment>
FIG. 6 is a sectional view of a head unit 261 according to the third embodiment. As illustrated in FIG. 6, in the third embodiment, the liquid ejecting head 26 is conveniently divided into a first portion P1 and a second portion P2 with a reference plane O parallel to the YZ plane as a boundary. The first portion P1 and the second portion P2 have a substantially plane-symmetric relationship with respect to the reference plane O. The structure of the first portion P1 located on the positive side in the X direction with respect to the reference plane O is the same as in the first embodiment. The second portion P2 has a structure in which the nozzle N and the piezoelectric element 44 are omitted from the configuration of the first embodiment.

  In the flow path substrate 32 of the third embodiment, a circulation flow path 328 is formed for each nozzle N of the first portion P1. The circulation channel 328 is a space surrounded by a groove formed on the surface of the channel substrate 32 facing the nozzle plate 62 and the surface. The communication channel 324 of the first part P1 and the communication channel 324 of the second part P2 communicate with each other via the circulation channel 328.

  The ink supplied to the inlet 482 of the first portion P1 is, as shown by the broken arrow in FIG. 6, in the first portion P1, the liquid storage chamber R → the supply liquid chamber 326 → the supply flow path 322 → the pressure. The liquid is supplied to the communication flow path 324 via a path called a chamber C. The ink that is not ejected from the nozzle N among the inks supplied to the communication channel 324 is supplied to the communication channel 324 of the second portion P2 via the circulation channel 328, and within the second portion P2, the communication channel 324 The liquid is discharged from the inlet 482 along a route of → pressure chamber C → supply channel 322 → supply liquid chamber 326 → liquid storage chamber R → inlet 482.

  As illustrated in FIG. 6, the liquid ejecting apparatus 100 according to the third embodiment includes a circulation mechanism 92. The circulation mechanism 92 is a mechanism for circulating the ink discharged from the liquid ejecting head 26 to the liquid ejecting head 26. The circulation mechanism 92 is a mechanism for circulating the ink supplied to the liquid ejecting head 26, and includes, for example, a supply flow path 921, a discharge flow path 922, and a circulation pump 923.

  The supply channel 921 is connected to the inlet 482 of the first part P1. The discharge channel 922 is connected to the inlet 482 of the second part P2. The supply channel 921 is a channel for supplying ink to the inlet 482 of the first portion P1, and the discharge channel 922 is a channel for discharging ink from the inlet 482 of the second portion P2. is there. The circulation pump 923 is a pressure feeding mechanism that sends the ink supplied from the discharge channel 922 to the supply channel 921. That is, the ink discharged from the inlet 482 of the second part P2 is returned to the inlet 482 of the first part P1 via the discharge flow path 922, the circulation pump 923, and the supply flow path 921.

  As understood from the above description, in the third embodiment, of the ink supplied to the first portion P1 from the supply channel 921, the ink not ejected from the nozzle N flows from the second portion P2 to the discharge channel 922. It is discharged and returned to the supply channel 921 by the circulation pump 923. That is, the ink inside the liquid jet head 26 circulates.

  As described above, according to the third embodiment, there is an advantage that the heat generated inside the head unit 261 is easily dissipated by the circulation of the ink. In particular, in the third embodiment, since ink circulates through a path including the liquid storage chamber R and the pressure chamber C located around the drive circuit 80, heat generated in the drive circuit 80 can be efficiently dissipated. is there.

<Modification>
The form exemplified above can be variously modified. Specific modifications that can be applied to the above-described embodiment will be exemplified below. Two or more aspects arbitrarily selected from the following exemplifications can be appropriately combined within a mutually consistent range.

(1) In each of the above-described embodiments, each individual radiator 90 is located on the side opposite to the nozzle N when viewed from the drive circuit 80, and the common radiator 265 is located on the opposite side to the drive circuit 80 when viewed from the individual radiator 90. Although the configuration located is illustrated, the positional relationship between the individual radiator 90 and the common radiator 265 is not limited to the above example. For example, at least one of the individual radiator 90 and the common radiator 265 may be located on the nozzle N side when viewed from the drive circuit 80. The positions where the individual heat radiators 90 and the common heat radiator 265 are mounted can be appropriately changed according to the configuration of the head unit 261.

(2) In each of the above-described embodiments, the common radiator 265 and the individual radiator 90 are thermally connected at the end of the drive circuit 80 in the longitudinal direction, but the common radiator 265 and the individual radiator 90 are connected. The positions to be set are not limited to the above examples. For example, the common radiator 265 and the individual radiator 90 may be in thermal contact with each other at the end of the drive circuit 80 in the short direction (that is, the Y direction).

  In each of the above-described embodiments, the common radiator 265 and the individual radiator 90 are thermally connected at the end of the drive circuit 80 on the negative side in the X direction. At the end on the side, the common radiator 265 and the individual radiator 90 may be thermally connected. For example, the individual radiator 90 may be configured to extend from the end of the drive circuit 80 on both the positive side and the negative side in the X direction. As understood from the above description, the position where the individual radiator 90 and the common radiator 265 are thermally connected is arbitrary.

(3) In each of the above-described embodiments, the individual radiator 90 is configured by the first portion 91, the second portion 92, and the third portion 93, but the configuration of the individual radiator 90 is not limited to the above examples. For example, the second portion 92 and the third portion 93 may be omitted in the individual heat radiator 90. In the above configuration, the common radiator 265 includes a portion extending from the surface on the head unit 261 side toward the end of the first portion 91. The said part and the 1st part 91 contact. As understood from the above description, the shape of the individual radiator 90 is arbitrary as long as it is thermally connected to the drive circuit 80 and the common radiator 265. Further, the shape of the common heat radiator 265 can be appropriately changed according to the shape of the individual heat radiator 90. It is not essential that the shape of each individual heat radiator 90 is the same.

(4) In each of the above-described embodiments, the configuration in which the individual heat radiator 90 is longer in the X direction and the Y direction than the drive circuit 80 is exemplified. However, the size relationship between the individual heat radiator 90 and the drive circuit 80 is It is not limited to the above examples. For example, the length of at least one of the X direction and the Y direction may be smaller for the individual radiator 90 than for the drive circuit 80. However, according to the above-described embodiment, the individual radiator 90 has a length in the X direction and the Y direction larger than that of the drive circuit 80. Since the heat is radiated over the entire drive circuit 80 as compared with the small configuration, there is an advantage that the temperature unevenness in the head unit 261 is eliminated. In addition, from the viewpoint of increasing the area for radiating heat, it is preferable that the individual radiator 90 be longer in the X and Y directions than the drive circuit 80.

(5) In each of the above-described embodiments, a configuration in which the liquid ejecting head 26 includes a support that supports the plurality of head units 261 is also adopted. The support and the common radiator 265 are separate members. The support is a box-shaped structure including a flat portion facing the fixing plate 263 and a frame-shaped sidewall protruding from the periphery of the flat portion to the positive side in the Z direction. The support is, for example, a carriage. The plurality of head units 261 joined to the fixing plate 263 are located in a space formed by the side wall and the flat part. The support has a higher thermal conductivity than the fixing plate 263, and is formed of, for example, a metal such as aluminum or copper. Therefore, the heat of the head unit 261 can be efficiently radiated from the support via the fixing plate 265. In the above configuration, the support may be used as the common radiator 265. Each individual heat radiator 90 is thermally connected to the flat portion of the support. According to the above configuration, it is not necessary to provide the common radiator 265 separately from the support, so that the liquid ejecting head 26 can be downsized.

(6) The fixing plate 263 may be omitted in the liquid jet head 26 described above. As illustrated in FIG. 7, each head unit 261 is joined to the common radiator 265. For example, the surface of the housing 48 of the head unit 261 on the side of the common radiator 265 and the common radiator 265 are fixed by the fixing part D. The fixing portion D is a fastener such as an adhesive or a screw. Further, the fixing portion D may be formed integrally with the common heat radiator 265.

(7) The driving element for ejecting the ink in the pressure chamber 342 from the nozzle N is not limited to the piezoelectric element 44 exemplified in the policy plan in each of the above embodiments. For example, a heating element that generates air bubbles inside the pressure chamber 342 by heating to change the pressure can be used as a driving element. As understood from the above example, the driving element is comprehensively expressed as an element for ejecting the liquid in the pressure chamber 342 from the nozzle N, and the operation method (piezoelectric method / thermal method) and the specific configuration are different. It doesn't matter.

(8) In each of the above-described embodiments, the line type liquid ejecting apparatus 100 in which the plurality of nozzles N are distributed over the entire width of the medium 12 has been exemplified. However, the serial type liquid ejecting apparatus that reciprocates a carrier on which the head unit 261 is mounted. The present invention can be applied to 100 as well.

(9) The liquid ejecting apparatus 100 exemplified in each of the above-described embodiments can be employed in various devices such as a facsimile device and a copying machine, in addition to a device dedicated to printing. However, the application of the liquid ejecting apparatus 100 of the present invention is not limited to printing. For example, a liquid ejecting apparatus that ejects a solution of a coloring material is used as a manufacturing apparatus that forms a color filter of a display device such as a liquid crystal display panel. In addition, a liquid ejecting apparatus that ejects a solution of a conductive material is used as a manufacturing apparatus that forms wiring and electrodes of a wiring board. A liquid ejecting apparatus that ejects a solution of an organic substance relating to a living body is used, for example, as a manufacturing apparatus that manufactures a biochip.

DESCRIPTION OF SYMBOLS 100 ... Liquid ejecting device, 12 ... Medium, 14 ... Liquid container, 20 ... Control unit, 22 ... Conveying mechanism, 26 ... Liquid ejecting head, 261 ... Head unit, 263 ... Fixed plate, 265 ... Common radiator, 267 ... Part, 28 housing, 30 passage structure, 32 passage substrate, 34 pressure chamber substrate, 342 pressure chamber, 42 diaphragm, 44 piezoelectric element, 46 first wiring substrate, 47 Second wiring board, 48 container, 486 second vibration absorber, 50 liquid ejector, 62 nozzle plate, 64 first vibration absorber, 641 elastic film, 643 support plate, 70 base member 72: wiring, 80: drive circuit, 90: individual radiator, R: liquid storage chamber, N: nozzle.

Claims (19)

A first head unit and a second head unit each including a liquid ejecting unit that ejects liquid from a nozzle, and a driving circuit that drives the liquid ejecting unit;
A first individual radiator thermally connected to a drive circuit of the first head unit;
A second individual heat radiator thermally connected to a drive circuit of the second head unit;
A liquid ejecting head, comprising: a common radiator thermally connected to the first individual radiator and the second individual radiator. The first individual radiator and the second individual radiator are located on a side opposite to the nozzle as viewed from the drive circuit,
The liquid ejecting head according to claim 1, wherein the common radiator is located on a side opposite to the drive circuit when viewed from the first individual radiator and the second individual radiator. A fixing plate to which the first head unit and the second head unit are fixed,
The liquid ejecting head according to claim 1, wherein the fixing plate is formed of metal. The liquid ejecting head according to claim 3, wherein the first head unit and the second head unit are joined to the fixing plate by an adhesive in which metal particles are dispersed. The liquid ejecting head according to claim 3, further comprising a wall formed between the common radiator and the fixing plate, between the first head unit and the second head unit. The liquid ejecting head according to claim 5, wherein the wall is formed of metal. The liquid ejecting head according to claim 5, wherein a liquid supplied to the liquid ejecting unit liquid passes through the inside of the wall. A support for supporting the first head unit and the second head unit,
The liquid ejecting head according to claim 3, wherein the fixing plate is in contact with the support. The liquid ejecting head according to claim 5, wherein the support has a higher thermal conductivity than the fixing plate. The liquid ejecting head according to any one of claims 1 to 4, wherein the common radiator is a support that supports the first head unit and the second head unit. The liquid ejecting head according to claim 8, wherein the support is made of metal. The drive circuit is long in plan view,
The first individual radiator and the second individual radiator face the surface of the drive circuit, and are thermally connected to the common radiator at an end in a longitudinal direction of the drive circuit. 11. The liquid ejecting head according to any one of items 11. The liquid ejecting unit includes:
A flow path structure in which a pressure chamber communicating with the nozzle is formed,
A drive element that is located on the opposite side of the nozzle in the flow path structure and changes the pressure of the pressure chamber,
A first wiring board on which a wiring for electrically connecting the drive circuit and the drive element is formed, which is located on a side opposite to the flow path structure when viewed from the drive element;
A flexible second wiring board having an end joined to the first wiring board;
The liquid ejecting head according to claim 1, wherein the drive circuit is mounted on a surface of the first wiring board opposite to the flow path structure. The liquid jet head according to claim 13, wherein the first individual radiator and the second individual radiator are thermally connected to the second wiring board. The liquid ejecting head according to claim 1, wherein the liquid supplied to the liquid ejecting unit passes through the inside of the common heat radiator. A liquid jet head,
And a control unit for controlling the liquid ejecting head.
The liquid jet head,
A first head unit and a second head unit each including a liquid ejecting unit that ejects liquid from a nozzle, and a driving circuit that drives the liquid ejecting unit;
A first individual radiator thermally connected to a drive circuit of the first head unit;
A second individual heat radiator thermally connected to a drive circuit of the second head unit;
A liquid ejecting apparatus, comprising: a common radiator thermally connected to the first individual radiator and the second individual radiator. The liquid jet head is a line head,
The liquid ejecting apparatus according to claim 16, further comprising a housing thermally connected to the common radiator and accommodating the liquid ejecting head. The liquid ejecting unit includes a channel structure in which a pressure chamber communicating with the nozzle is formed,
A circulation mechanism that recirculates the liquid discharged from the head unit via the pressure chamber to the head unit,
The liquid ejecting apparatus according to claim 17. The liquid ejecting head includes a liquid storage chamber that stores liquid supplied to the liquid ejecting unit,
19. The liquid ejecting apparatus according to claim 18, wherein the circulation mechanism circulates the liquid discharged from the head unit via the liquid storage chamber to the liquid ejecting head.

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