Liquid dispensing head

Abstract

To provide a liquid dispensing head that can suppress the transfer of heat generated by the heating element to the actuator. [Solution] The liquid discharge head of the embodiment comprises a nozzle plate, an actuator, a flow path member, a first temperature-regulating flow path forming member, a drive IC, and a second temperature-regulating flow path forming member. The nozzle plate has a nozzle hole formed therein for discharging liquid. The actuator changes the volume of the pressure chamber from which the liquid is discharged. The flow path member forms a flow path for supplying the liquid to the actuator. The first temperature-regulating flow path forming member forms a first temperature-regulating flow path for controlling the temperature of the actuator. The drive IC drives the actuator. The second temperature-regulating flow path forming member forms a second temperature-regulating flow path for suppressing the temperature rise of the drive IC. The second temperature-regulating flow path forming member has a heat transfer section to which heat from the drive IC is transferred, and a forming section that forms the branching and merging points of the first temperature-regulating flow path and the second temperature-regulating flow path. The forming section has a lower thermal conductivity than the heat transfer section.

Description

Technical Field

[0001] Embodiments of the present invention relate to a liquid ejection head.

Background Art

[0002] As a liquid ejection head that ejects liquid such as ink, a technique for achieving stable printing by controlling the ink temperature of an actuator is known. Further, since heat generating elements such as a driving IC that drives the actuator generate heat during printing, the liquid ejection head is required to have a mechanism that adjusts the temperature of the actuator and suppresses the temperature rise of heat generating elements such as the driving IC. Accordingly, there has been known a liquid ejection head that performs temperature adjustment such as ink temperature control and cooling of heat generating elements by using a temperature adjustment flow path. However, when the same temperature adjustment flow path is branched and used for both ink temperature control and cooling of the heat generating element, heat generated by the heat generating element may transfer to the actuator from members constituting the temperature adjustment flow path or temperature adjustment water, which may make it difficult to control the temperature of the actuator.

Prior Art Literature

Patent Literature

[0003]

Patent Literature 1

Summary of the Invention

Problem to be Solved by the Invention

[0004] An object of the present invention is to provide a liquid ejection head capable of suppressing heat transfer of heat generated by a heat generating element to an actuator.

Means for Solving the Problem

[0005] The liquid discharge head of the embodiment comprises a nozzle plate, an actuator, a flow path member, a first temperature control flow path forming member, a drive IC, and a second temperature control flow path forming member. The nozzle plate has a nozzle hole formed therein for discharging liquid. The actuator changes the volume of the pressure chamber from which the liquid is discharged. The flow path member forms a flow path for supplying the liquid to the actuator. The first temperature control flow path forming member forms a first temperature control flow path for controlling the temperature of the actuator. The drive IC drives the actuator. The second temperature control flow path forming member forms a second temperature control flow path for suppressing the temperature rise of the drive IC. The second temperature control flow path forming member has a heat transfer section to which heat from the drive IC is transferred, and a forming section that forms the branching and merging points of the first temperature control flow path and the second temperature control flow path. The forming section has a lower thermal conductivity than the heat transfer section. [Brief explanation of the drawing]

[0006] [Figure 1] A perspective view showing the configuration of a liquid dispensing head according to an embodiment. [Figure 2] An exploded perspective view showing the configuration of a liquid dispensing head according to an embodiment. [Figure 3] A side view showing the configuration of a liquid dispensing head according to an embodiment. [Figure 4] A cross-sectional view showing the configuration of a liquid dispensing head according to the embodiment. [Figure 5] A diagram showing the configuration of the liquid discharge head according to the embodiment, viewed from the nozzle plate side. [Figure 6] A perspective view showing a partial cross-sectional view of the head body and manifold unit of the liquid discharge head according to the embodiment. [Figure 7] A cross-sectional view showing the configuration of the head body and manifold unit according to the embodiment. [Figure 8] A cross-sectional view showing the configuration of the head body and manifold unit according to the embodiment. [Figure 9] A diagram showing the configuration of the head body according to the embodiment, with some parts omitted. [Figure 10]An exploded perspective view showing the configuration of a temperature control flow channel unit according to an embodiment. [Figure 11] A perspective view showing an enlarged view of the main components of the liquid discharge head according to the embodiment. [Modes for carrying out the invention]

[0007] The liquid discharge head 1 according to the embodiment will be described below with reference to Figures 1 to 11. Figure 1 is a perspective view showing the configuration of the liquid discharge head 1 according to the embodiment, with the cover 15 omitted. Figure 2 is an exploded perspective view showing the configuration of the liquid discharge head 1, with the cover 15 omitted. Figure 3 is a side view showing the configuration of the liquid discharge head 1. Figure 4 is a cross-sectional view showing the configuration of the liquid discharge head 1, with the cover 15 omitted.

[0008] Figure 5 shows the configuration of the liquid discharge head 1 as seen from the nozzle plate 114 side. Figure 6 is a perspective view showing a partial cross-section of the configuration of the head body 11 and manifold unit 12 of the liquid discharge head 1. Figure 7 is a cross-sectional view showing the configuration of the head body 11 and manifold unit 12. Figure 8 is an enlarged cross-sectional view showing the configuration of the head body 11 and manifold unit 12.

[0009] Figure 9 is a diagram showing the configuration of the head body 11 with some parts omitted. Figure 10 is an exploded perspective view showing the configuration of the temperature control flow path unit 13. Figure 11 is an enlarged perspective view showing the configuration of the manifold unit 12 and the temperature control flow path unit 13 as the main components of the liquid discharge head 1. In Figure 2, an example of the flow of temperature-controlled water is shown by a dashed arrow.

[0010] Figures 1 through 11 show the mutually orthogonal X, Y, and Z axes. In the following explanation, the direction along the X axis will be referred to as the first direction X, the direction along the Y axis as the second direction Y, and the direction along the Z axis as the third direction Z. Also, for illustrative purposes, the components in each figure have been enlarged, reduced, or omitted as appropriate.

[0011] The liquid ejection head 1 is, for example, an inkjet head installed in a liquid ejection device such as an inkjet recording device. The liquid ejection head 1 is installed in a head unit that includes a supply tank as a liquid storage section, which is installed in the liquid ejection device.

[0012] The liquid ejection head 1 is supplied with ink as liquid stored in a supply tank. The liquid ejection head 1 may be a non-circulating head that does not circulate ink, or it may be a circulating head that circulates ink. In this embodiment, the liquid ejection head 1 will be described using an example of a non-circulating head. The liquid ejection head 1 is also connected to a temperature control device provided in the liquid ejection apparatus, and is supplied with a temperature-controlled liquid (temperature-controlled water) that controls the temperature of the heating element and actuator. Together with the temperature control device, the liquid ejection head 1 constitutes a circulation structure for the temperature-controlled water.

[0013] As shown in Figures 1 to 4, the liquid discharge head 1 comprises a head body 11, a manifold unit 12, a temperature control flow path unit 13, a circuit board 14, and a cover 15. For example, the liquid discharge head 1 is a side-chute type four-row integrated head having two sets of head bodies 11, each having a pair of actuators 113.

[0014] The head body 11 discharges liquid. As shown in Figures 3 to 9, the head body 11 comprises a base plate 111, a frame 112, an actuator 113, a nozzle plate 114, and a mask plate 115. The head body 11 also has a common liquid chamber 116. In this embodiment, an example in which one head body 11 has two actuators 113 will be described.

[0015] As shown in FIGS. 7 to 9, the base plate 111 is formed into a rectangular plate shape from, for example, a ceramic material. The base plate 111 is formed in, for example, a rectangular shape elongated in one direction (first direction X). As shown in FIG. 9, the base plate 111 includes a single supply port 1111 and one or more discharge ports 1112. A pair of actuators 113 is provided on the base plate 111, and a wiring pattern for driving the actuators 113 is formed thereon. The supply port 1111 and the discharge port 1112 are through-holes penetrating between both main surfaces of the base plate 111.

[0016] The single supply port 1111 is provided, for example, at a position facing a first common liquid chamber 1161 described later of the common liquid chamber 116. The supply port 1111 is, for example, an elongated hole elongated in one direction along the longitudinal direction (first direction X) of the first common liquid chamber 1161. The supply port 1111 is, for example, a rectangular shape elongated in one direction, or an elongated hole with semicircular ends and uniform width. The longitudinal width of the supply port 1111 is, for example, equal to or longer than the longitudinal width (length) of the actuator 113, or smaller than the length of the actuator 113, and set to a length approximately equal to the range (full nozzle range) where the pressure chambers 1131 driven during normal ink ejection formed in the actuator 113 are provided.

[0017] Two discharge ports 1112 are provided, for example, at positions facing at least one third common liquid chamber 1163 among two third common liquid chambers 1163 described later of the common liquid chamber 116. For example, as shown in FIG. 9, the discharge ports 1112 are provided on the base plate 111 such that they are adjacent to one end in the longitudinal direction of the pair of actuators 113 and disposed in one of the third common liquid chambers 1163. Note that, for example, two discharge ports 1112 may be provided in each of the two third common liquid chambers 1163 of the common liquid chamber 116.

[0018] As shown in FIG. 9, the frame body 112 is fixed to one main surface of the base plate 111 with an adhesive or the like. The frame body 112 surrounds the supply port 1111, the plurality of discharge ports 1112, and the actuators 113 provided on the base plate 111.

[0019] For example, the frame body 112 is formed in a rectangular frame shape elongated in one direction (the first direction X), thereby forming an opening elongated in one direction along the longitudinal direction of the frame body 112. In the opening of the frame body 112, a pair of actuators 113, a supply port 1111 and two discharge ports 1112 are arranged.

[0020] The actuator 113 is formed in a plate shape elongated in one direction (the first direction X). The pair of actuators 113 are adhered to the mounting surface of the base plate 111. As shown in FIG. 9, the pair of actuators 113 are provided on the base plate 111 in two rows in the short direction (the second direction Y) orthogonal to the longitudinal direction of the actuators 113 with the supply port 1111 interposed therebetween. The actuator 113 is arranged in the opening of the frame body 112 and adhered to the main surface of the base plate 111. As a specific example, the actuator 113 is formed by opposing and adhering two rectangular plate-shaped piezoelectric materials elongated in one direction such that their polarization directions are opposite to each other. Here, the piezoelectric material is, for example, PZT (lead zirconate titanate). The actuator 113 is adhered to the mounting surface of the base plate 111 by, for example, a thermosetting epoxy adhesive.

[0021] The actuator 113 has, for example, a plurality of pressure chambers 1131 arranged at equal intervals in the longitudinal direction (the first direction X). In the actuator 113, a plurality of grooves are formed along the longitudinal direction of the actuator 113 on the main surface side opposite to the base plate 111 side, and the pressure chambers 1131 are formed by these grooves. In other words, the actuator 113 has a plurality of walls 1133 arranged at equal intervals in the longitudinal direction, with grooves formed between the walls. The plurality of walls 1133 form a plurality of pressure chambers 1131 between adjacent walls. That is, the plurality of walls 1133 are partition walls that separate the plurality of pressure chambers 1131. Further, the walls 1133 are piezoelectric bodies serving as driving elements that change the volume of the pressure chambers 1131 when a driving voltage is applied thereto.

[0022] The side of the actuator 113 opposite to the base plate 111 is bonded to the nozzle plate 114. The actuator 113 also has a wiring pattern formed on it for driving multiple pressure chambers 1131.

[0023] The pressure chamber 1131 is a pressure chamber for ejecting ink from the nozzle hole 1141 during printing or other operations by the liquid ejection head 1. In this embodiment, an example in which the actuator 113 has multiple pressure chambers 1131 has been described, but for example, a configuration having multiple pressure chambers 1131 and alternating air chambers that do not eject ink may also be used.

[0024] As shown in Figures 4, 5, 7, and 8, the nozzle plate 114 is formed in a plate shape. The nozzle plate 114 is fixed to the main surface of the frame 112 opposite to the base plate 111 with an adhesive or the like. The nozzle plate 114 has a plurality of nozzle holes 1141 formed at positions opposite to a plurality of pressure chambers 1131. In this embodiment, the nozzle plate 114 has two rows of nozzle rows 1142 in which the plurality of nozzle holes 1141 are arranged in one direction (first direction X). In this embodiment, since the liquid discharge head 1 has two sets of head bodies 11, as shown in Figure 5, the liquid discharge head 1 has four rows of nozzle rows 1142.

[0025] Multiple nozzle holes 1141 facing multiple pressure chambers 1131 are holes through which ink (droplets) are ejected when the liquid ejection head 1 performs operations such as printing.

[0026] The mask plate 115 covers, for example, the main outer surface of the nozzle plate 114, the outer periphery of the nozzle plate 114, the outer periphery of the frame 112, and the outer periphery of the base plate 111. The mask plate 115 also covers the first manifold 1214 of the manifold unit 12, which will be described later.

[0027] As shown in Figure 5, the mask plate 115 has a pair of windows 1151 that expose a nozzle row 1142, which is made up of a plurality of nozzle holes 1141 that discharge liquid from a pair of nozzle plates 114.

[0028] As shown in Figure 9, the common liquid chamber 116 communicates with the supply port 1111. The common liquid chamber 116 is provided around a pair of actuators 113. Specifically, the common liquid chamber 116 communicates with the primary and secondary sides of the multiple pressure chambers 1131 of each actuator 113. The common liquid chamber 116 also communicates with the discharge port 1112.

[0029] As a specific example, as shown in Figure 9, the common liquid chamber 116 has a first common liquid chamber 1161 that is long in one direction (first direction X), two second common liquid chambers 1162 that are long in one direction (first direction X), and a third common liquid chamber 1163 that connects both ends of the first common liquid chamber 1161 and both ends of the two second common liquid chambers 1162. Furthermore, the common liquid chamber 116 connects the supply port 1111 to one opening of the plurality of pressure chambers 1131 of the actuator 113 via the first common liquid chamber 1161, and connects the third common liquid chamber 1163 to the other opening of the plurality of pressure chambers 1131 via the second common liquid chambers 1162.

[0030] The first common liquid chamber 1161 is formed between a pair of actuators 113. The first common liquid chamber 1161 constitutes an ink flow path from the supply port 1111 to one opening of the multiple pressure chambers 1131 of each actuator 113. The first common liquid chamber 1161 also constitutes an ink flow path from the supply port 1111 to two third common liquid chambers 1163 at both ends in the longitudinal direction (first direction X) of the first common liquid chamber 1161 (actuator 113).

[0031] The second common liquid chamber 1162 is formed between each actuator 113 and the frame 112. The second common liquid chamber 1162 forms a flow path for ink from the third common liquid chamber 1163 to the other opening of the multiple pressure chambers 1131.

[0032] The third common liquid chamber 1163 is adjacent to, for example, both longitudinal ends of the actuator 113. The third common liquid chamber 1163 connects the first common liquid chamber 1161 and the two second common liquid chambers 1162 at both longitudinal ends of the pair of actuators 113. The third common liquid chamber 1163 forms a flow path for some ink from the first common liquid chamber 1161 to the second common liquid chambers 1162 without passing through the multiple pressure chambers 1131 of each actuator 113. The third common liquid chamber 1163 also forms a flow path for ink from the first common liquid chamber 1161 and the two second common liquid chambers 1162 to the outlet 1112.

[0033] As shown in Figures 1 to 8, the manifold unit 12 comprises a manifold 121, a top plate 122, an ink supply pipe 123, an ink discharge pipe 124, a first temperature-controlled water supply pipe 125, a first temperature-controlled water discharge pipe 126, a damper 127, and a bypass flow path 128. The manifold unit 12 constitutes a flow path member that forms the flow path for the ink, and a first temperature-controlled flow path forming member that forms the flow path for the temperature-controlled water that controls the temperature of the actuator 113. The number of ink supply pipes 123 and ink discharge pipes 124 can be set as appropriate. The number of ink supply pipes 123, ink discharge pipes 124, first temperature-controlled water supply pipes 125, and first temperature-controlled water discharge pipes 126 can be set as appropriate.

[0034] The manifold 121 is formed in the shape of a plate or a block. As shown in Figures 6 to 8, the manifold 121 includes a supply passage 1211 that is continuous with the supply port 1111 of the base plate 111 and forms a liquid supply passage, a discharge passage 1212 that is continuous with the discharge port 1112 of the base plate 111 and forms a liquid discharge passage, and a first temperature control passage 1213 that forms a passage for a temperature control fluid. Since the manifold 121 is connected to a pair of head bodies 11, it has a pair of supply passages 1211 and a pair of discharge passages 1212.

[0035] One main surface of the manifold 121 is fixed to the main surface of the base plate 111. The top plate 122 is fixed to the main surface of the manifold 121 opposite to the main surface to which the base plate 111 is fixed. The ink supply pipe 123, ink discharge pipe 124, first temperature-controlled water supply pipe 125, and first temperature-controlled water discharge pipe 126 are fixed to the manifold 121, for example, via the top plate 122.

[0036] Manifold 121 comprises, for example, a first manifold 1214 and a second manifold 1215. Manifold 121 is formed by assembling the first manifold 1214 and the second manifold 1215 together.

[0037] The supply passage 1211 is a rectangular liquid chamber formed in the manifold 121 by holes or grooves, which is elongated in one direction (first direction X). The supply passage 1211 fluidly connects the ink supply pipe 123 and the supply port 1111 of the base plate 111.

[0038] For example, the supply passage 1211 is a rectangular liquid chamber that extends along the longitudinal direction of the actuator 113 and the longitudinal direction of the supply port 1111. The supply passage 1211 is the liquid flow path between the ink supply pipe 123 and the supply port 1111. The supply port 1111 is continuous with one end of the supply passage 1211, and a damper 127 is provided in the ceiling portion 12111 on the other end of the supply passage 1211.

[0039] The discharge passage 1212 is a flow path formed in the manifold 121 by holes or grooves. The discharge passage 1212 fluidly connects, for example, the ink discharge pipe 124 and the two discharge ports 1112 of the base plate 111.

[0040] The first temperature control channel 1213 is formed in the manifold 121 by holes or grooves. Temperature-controlled water flows through the first temperature control channel 1213 to control (temperature-adjust) the temperature of the actuator 113 and / or the temperature of the ink flowing through the actuator 113. The first temperature control channel 1213 fluidly connects the first temperature-controlled water supply pipe 125 and the first temperature-controlled water discharge pipe 126. The first temperature control channel 1213 adjusts the temperature of the head body 11, which is the liquid discharge section. For example, the first temperature control channel 1213 adjusts the temperature of the actuator 113 to a predetermined temperature.

[0041] The primary and secondary ends of the first temperature control channel 1213 are openings that connect to the first temperature-controlled water supply pipe 125 and the first temperature-controlled water discharge pipe 126, which are provided on one main surface of the manifold 121. The first temperature control channel 1213 is also formed to allow heat exchange with the base plate 111, which is fixed to the manifold 121. The first temperature control channel 1213 controls the temperature of the actuator 113 via the base plate 111.

[0042] The first manifold 1214 is formed in the shape of a rectangular plate. The first manifold 1214 has grooves and openings that form, for example, part of a pair of supply passages 1211, part of a pair of discharge passages 1212, and part of the first temperature control passage 1213. The arrangement and size of the grooves and openings that form part of the supply passages 1211 and discharge passages 1212 are appropriately set based on the shapes of the supply passages 1211 and discharge passages 1212, as well as the shapes of other fluid passages.

[0043] The second manifold 1215 is formed in the shape of a rectangular plate. The second manifold 1215 has grooves and openings that form, for example, part of a pair of supply passages 1211, part of a pair of discharge passages 1212, and part of the first temperature control passage 1213. The arrangement and size of the grooves and openings that form part of the supply passages 1211 and discharge passages 1212 are appropriately set based on the shapes of the supply passages 1211 and discharge passages 1212, as well as the shapes of other fluid passages.

[0044] The first manifold 1214 and the second manifold 1215 are joined together to form a supply passage 1211, a discharge passage 1212, and a first temperature control passage 1213.

[0045] The top plate 122 is provided on the side of the manifold 121 opposite to the side on which the base plate 111 is provided. The top plate 122 has openings that connect the ink supply pipe 123, the ink discharge pipe 124, the first temperature-controlled water supply pipe 125, and the first temperature-controlled water discharge pipe 126 to the supply passage 1211, the discharge passage 1212, and the first temperature control passage 1213 of the manifold 121. For example, the top plate 122 is formed from two plate-like members. One of the ink supply pipes 123 and ink discharge pipe 124, as well as one of the first temperature-controlled water supply pipe 125 and the first temperature-controlled water discharge pipe 126, are provided on one plate-like member. The other of the ink supply pipes 123 and ink discharge pipe 124, as well as the other of the first temperature-controlled water supply pipe 125 and the first temperature-controlled water discharge pipe 126, are provided on the other plate-like member.

[0046] The ink supply pipe 123 is connected to the supply passage 1211. The ink discharge pipe 124 is connected to the discharge passage 1212. In this embodiment, since the liquid discharge head 1 has a pair of head bodies 11, a pair of ink supply pipes 123 and ink discharge pipes 124 are provided. The first temperature-controlled water supply pipe 125 and the first temperature-controlled water discharge pipe 126 are pipes connected to the primary and secondary sides of the first temperature control passage 1213.

[0047] In this embodiment, a pair of ink supply pipes 123 and a first temperature-controlled water discharge pipe 126 are arranged on one end of the manifold 121 in the longitudinal direction, and a pair of ink discharge pipes 124 and a first temperature-controlled water supply pipe 125 are arranged on the other end of the manifold 121 in the longitudinal direction.

[0048] As shown in Figures 6 to 8, the damper 127 is formed as an elastically deformable thin film or sheet. As shown in Figure 7, the damper 127 covers the ceiling portion 12111 of the supply passage 1211 formed in the second manifold 1215. The damper 127 elastically deforms in response to pressure fluctuations in the supply passage 1211. One side of the damper 127 faces the supply passage 1211.

[0049] As a specific example, the damper 127 is formed from a polyimide film. The damper 127 is formed in a rectangular shape, elongated in the same direction as the longitudinal direction (first direction X) of the opening in the ceiling portion 12111 of the supply passage 1211, which is long in one direction (first direction X).

[0050] As shown in Figure 6, the bypass channel 128 connects the ceiling portion 12111 of the supply channel 1211 to the common liquid chamber 116 or the secondary side of the common liquid chamber 116. The common liquid chamber 116 or the secondary side of the common liquid chamber 116 to which the bypass channel 128 connects is, for example, the second common liquid chamber 1162 or the third common liquid chamber 1163 of the common liquid chamber 116, the discharge channel 1212, or the ink discharge pipe 124. The fluid resistance of the bypass channel 128 is greater than the fluid resistance of the supply channel 1211 and the fluid resistance of the common liquid chamber 116.

[0051] The bypass channel 128 bypasses the supply channel 1211 and the common liquid chamber 116, thereby discharging air bubbles from the supply channel 1211 during maintenance or ink refilling. The bypass channel 128 is formed with a rectangular or circular cross-sectional shape. The shape of the bypass channel 128 can be, for example, straight or partially bent into a vent shape.

[0052] As shown in Figures 2, 4, and 10, the temperature control flow path unit 13 includes, for example, a temperature control flow path section 131, a top plate 132 for temperature-controlled water, a second temperature-controlled water supply pipe 133, and a second temperature-controlled water discharge pipe 134. The temperature control flow path unit 13 is connected to the temperature control device of the liquid discharge device. The temperature control flow path unit 13 constitutes a second temperature control flow path forming member that cools the drive IC 142, which is a heat-generating element, and suppresses the temperature rise of the drive IC 142. The temperature control flow path section 131 is connected to the second temperature-controlled water supply pipe 133 and the second temperature-controlled water discharge pipe 134 via the top plate 132 for temperature-controlled water. The temperature control flow path section 131 includes a branch flow path 1311 connected to the second temperature-controlled water supply pipe 133, a second temperature control flow path 1312 for cooling a plurality of drive ICs, which are heat-generating elements and will be described later, and a merging flow path 1313.

[0053] The branch channel 1311 is a channel that branches the temperature-controlled water supplied from the second temperature-controlled water supply pipe 133 in two directions. One of the channels branched by the branch channel 1311 is connected to the first temperature-controlled channel 1213, and the other channel branched by the branch channel 1311 is connected to the second temperature-controlled channel 1312. In other words, the branch channel 1311 branches the first temperature-controlled channel 1213 and the second temperature-controlled channel 1312 to supply temperature-controlled water to the manifold unit 12 and the temperature-controlled channel unit 13.

[0054] The second temperature control channel 1312 is connected to one of the channels branched off by the branch channel 1311. The second temperature control channel 1312 has fewer channels than the number of drive ICs on the primary side and branches into multiple channels, forming a channel where the multiple channels merge into one on the secondary side. Temperature-controlled water that cools the drive IC 142 flows through the second temperature control channel 1312.

[0055] As a specific example, in this embodiment, there are four rows of nozzles 1142, four actuators 113 (four rows), and four drive ICs 142 (four rows). Therefore, as shown in Figures 2, 4, and 10, the temperature control flow path section 131 has three flow path sections 13121 that constitute the second temperature control flow path 1312. These three flow path sections 13121 are long in one direction (first direction X) and are arranged side by side in a direction perpendicular to the longitudinal direction of the flow path section 13121 (second direction Y).

[0056] The flow channel section 13121 is a heat transfer section to which heat from the drive IC 142 is transferred. The three flow channel sections 13121 are composed of a pair (two) single-row temperature control flow channel sections 13122 and one multi-row temperature control flow channel section 13123. The pair of single-row temperature control flow channel sections 13122 are arranged at both ends (outside) in the direction of alignment of the three flow channel sections 13121 (second direction Y). Each of the pair of single-row temperature control flow channel sections 13122 cools one drive IC 142 that drives the actuator 113 that ejects ink from a single-row nozzle row 1142. The corresponding drive IC 142 is in contact with the outer surface of the single-row temperature control flow channel section 13122.

[0057] The multi-row temperature control channel section 13123 is positioned on the inside in the direction of alignment of the three channel sections 13121 (second direction Y). That is, the multi-row temperature control channel section 13123 is positioned between the pair of single-row temperature control channel sections 13122 in the direction of alignment of the three channel sections 13121 (second direction Y). The multi-row temperature control channel section 13123 cools two drive ICs 142 that drive two actuators 113 that eject ink from two adjacent rows of nozzles 1142 of the two sets of head bodies 11. The two corresponding drive ICs 142 are in contact with different outer surfaces of the multi-row temperature control channel section 13123.

[0058] For example, as shown in Figures 4 and 10, the width WA of the channel 131221 formed by the single-row temperature control channel section 13122 is narrower than the width WB of the channel 131231 formed by the multi-row temperature control channel section 13123. The widths WA and WB of the channel 131221 and the channel 131231 are the widths in the second direction Y in Figure 10. Furthermore, the cross-sectional area of ​​the channel 131221 formed by the single-row temperature control channel section 13122 is smaller than the cross-sectional area of ​​the channel in the multi-row temperature control channel section 13123. This is because the single-row temperature control channel section 13122 cools one drive IC 142, while the multi-row temperature control channel section 13123 cools two drive ICs 142. Therefore, in order to make the cooling capacity of the multi-row temperature control channel section 13123 higher than that of the single-row temperature control channel section 13122, the width WB of the channel 131231 of the multi-row temperature control channel section 13123 is larger than the width WA of the channel 131221 of the single-row temperature control channel section 13122.

[0059] The confluence channel 1313 combines the first temperature control channel 1213 and the second temperature control channel 1312 and connects to the second temperature-controlled water discharge pipe 134. In other words, the confluence channel 1313 combines the temperature-controlled water that has flowed through the first temperature control channel 1213 and the second temperature control channel 1312 and discharges it.

[0060] Such a temperature control flow channel section 131 includes, for example, a temperature control manifold 1314, a cover 1315 that covers the temperature control manifold 1314, and a pair of temperature control blocks 1316 provided on the cover 1315.

[0061] The second temperature control channel 1312 is a channel formed by holes and grooves formed in the temperature control manifold 1314, the cover 1315, and the pair of temperature control blocks 1316.

[0062] The temperature control manifold 1314 is formed in the shape of a plate or block. The temperature control manifold 1314 is fixed to the manifold 121, for example. The temperature control manifold 1314 has two openings 13141 for arranging a part of the wiring film 141 on which the drive IC 142 of the circuit board 14 (described later) is mounted, and the printed wiring board 143. The openings 13141 are aligned with the longitudinal direction (first direction X) of the flow path section 13121.

[0063] The temperature control manifold 1314 has three sections adjacent to the two openings 13141, each of which constitutes part of the flow path section 13121. For example, a groove 13142 is formed in the temperature control manifold 1314. The groove 13142 has a shape in which one flow path branches into three flow paths: two single-row temperature control flow path sections 13122 forming flow paths 131231 and one multi-row temperature control flow path section 13123 forming flow path 131231, and then merges.

[0064] The cover 1315 is formed in a plate shape. The cover 1315 has two openings 13151 along the longitudinal direction (first direction X) of the flow channel 13121, on which a portion of the wiring film 141 and the printed circuit board 143 are arranged. The cover 1315 covers the groove 13142 formed in the temperature control manifold 1314 and is liquid-tightly fixed to the temperature control manifold 1314. Together with the temperature control manifold 1314, the cover 1315 constitutes the second temperature control flow channel 1312. When the cover 1315 is assembled integrally with the temperature control manifold 1314, the two openings 13151 of the cover 1315 and the opening 13141 of the temperature control manifold 1314 face each other. The cover 1315 has multiple openings, for example, that connect the second temperature control flow channel 1312 to the branch flow channel 1311 and the merging flow channel 1313.

[0065] The temperature control block 1316 has grooves and openings formed inside to form branching channels 1311 or confluence channels 1313. Of the pair of temperature control blocks 1316, one forms a branching channel 1311, and the other forms a confluence channel 1313. One temperature control block 1316 is a branching point forming section (forming section) that forms a branching point for branching the temperature-controlled water, and the other temperature control block 1316 is a confluence point forming section (forming section) that forms a confluence point for confluence of the temperature-controlled water. The pair of temperature control blocks 1316 are fixed to the cover 1315. The pair of temperature control blocks 1316 face each other in the first direction X with an interval that allows the wiring film 141 of the circuit board 14 and the printed wiring board 143 (described later) to be arranged. The temperature control block 1316 has piping 13161 that connects, for example, a branch channel 1311 or a merging channel 1313 to the first temperature-controlled water supply pipe 125 or the first temperature-controlled water discharge pipe 126. The temperature control block 1316 also has, for example, four circuit boards 14, which will be described later, and multiple ribs 13162 and multiple grooves 13163 that support them.

[0066] The temperature-controlled water top plate 132 is provided on the side opposite to the side on which the cover 1315 of the pair of temperature-controlled blocks 1316 is provided. For example, a pair of temperature-controlled water top plates 132 are provided. Each temperature-controlled water top plate 132 has an opening for connecting a second temperature-controlled water supply pipe 133 or a second temperature-controlled water discharge pipe 134 to a branch channel 1311 or a merging channel 1313 of the temperature-controlled block 1316. The temperature-controlled water top plate 132 has a plurality of grooves formed therein for arranging and supporting, for example, a printed circuit board 143.

[0067] In the temperature control flow channel unit 13 configured in this way, the thermal conductivity of the flow channel section 13121, which is the heat transfer section to which the heat from the drive IC 142 is transferred, is higher than the thermal conductivity of the temperature control block 1316, which is the forming section (branching point forming section and confluence point forming section) that forms the branching and confluence points of the temperature-controlled water. That is, the temperature control manifold 1314 that forms the three flow channel sections 13121 is formed of a material with a higher thermal conductivity than the temperature control block 1316. For example, the temperature control manifold 1314 is formed of a metal material, and the temperature control block 1316 is formed of a resin material or the like with a lower thermal conductivity than the temperature control manifold 1314.

[0068] As a specific example, in the temperature control flow path unit 13, the temperature control manifold 1314 is made of a metal material, and the cover 1315, temperature control block 1316, and temperature control water top plate 132 are made of a resin material with a lower thermal conductivity than the temperature control manifold 1314.

[0069] Furthermore, the temperature control flow path unit 13 is assembled integrally with the manifold unit 12 by connecting the piping 13161 provided on a pair of temperature control blocks 1316 to the first temperature-controlled water supply pipe 125 and the first temperature-controlled water discharge pipe 126. Specifically, as shown in Figure 11, the temperature control flow path unit 13, which is the second temperature control flow path forming member, comes into contact with the manifold unit 12, which is the first temperature control flow path forming member, only at the piping 13161 of the temperature control block 1316, which is the branching and merging point of the first temperature control flow path and the second temperature control flow path. Also, the manifold unit 12 does not come into contact with the temperature control flow path unit 13 except, for example, the piping 13161 of the temperature control block 1316, which is part of the branching and merging point of the temperature control flow path unit 13.

[0070] As shown in Figures 1 to 4, one end of the circuit board 14 is connected to the wiring pattern of the actuator 113 via the wiring pattern of the base plate 111. The circuit board 14 comprises, for example, a wiring film 141, a drive IC 142 mounted on the wiring film, and a printed wiring board 143 mounted on the wiring film.

[0071] The circuit board 14 drives the actuator 113 by applying a drive voltage to it via the wiring pattern on the base plate 111 using the drive IC 142, thereby increasing or decreasing the volume of the pressure chamber 1131 and ejecting droplets from the nozzle hole 1141.

[0072] The wiring film 141 is a film substrate formed in a so-called film shape, on which a wiring pattern is formed. Multiple wiring films 141 are provided, for example. The wiring film 141 is, for example, a COF (Chip on Film) on which a drive IC 142 is mounted. For example, the number of wiring films 141 is the same as the number of actuators 113 provided on one head body 11, that is, the same number as the nozzle rows 1142. Each wiring film 141 is connected to one actuator 113. Note that multiple wiring films 141 may be connected to one actuator 113. In this case, the number of wiring film rows and drive IC rows, which are composed of multiple wiring films 141 and drive ICs 142 mounted on the wiring films 141, will be the same as the number of actuators 113.

[0073] In this embodiment, the head body 11 is configured to have two rows of nozzles 1142 (two actuators 113), so two wiring films 141 are provided on one head body 11. The liquid discharge head 1 having two sets of head bodies 11 has four wiring films 141. The four wiring films 141 are arranged, for example, to extend in a third direction Z, and in this orientation, they are arranged side by side in a second direction Y.

[0074] The drive IC 142 is electrically connected to the wiring pattern formed in the pressure chamber 1131 via the wiring film 141. The drive IC 142 is a heat-generating element. The drive IC 142 is mounted on the outer surface of the wiring film 141. Here, the outer surface of the wiring film 141 is the surface opposite to the surface (inner surface) on which the two wiring films 141 of one head body 11 face each other when the head body 11 is positioned to extend in the third direction Z. In other words, the outside of the wiring film 141 means the outside in the second direction Y of the head body 11, when the center side of the second direction Y of the head body 11 is considered the inside. For this reason, the outer surfaces of the two inner wiring films 141 of the four wiring films 141 of the two sets of head bodies 11 face each other.

[0075] The drive IC 142 has a surface opposite to the mounting surface on the wiring film 141 that abuts against the outer surface of the flow channel 13121. For example, the surface of the drive IC 142 is in direct contact with the outer surface of the flow channel 13121. One drive IC 142 is provided for each wiring film 141. Alternatively, multiple drive ICs 142 may be provided to drive one actuator 113, and these multiple drive ICs 142 may be provided on a single wiring film 141 to form a drive IC array. In this case, multiple drive ICs 142 in the same drive IC array abut against the corresponding flow channel 13121.

[0076] One printed circuit board 143 is, for example, a PWA (Printing Wiring Assembly) on which various electronic components and connectors are mounted.

[0077] The cover 15 covers or houses a portion of the head body 11, a portion of the manifold unit 12, and the circuit board 14.

[0078] The liquid discharge head 1 configured in this way has a first temperature control channel 1213 for controlling the temperature of the actuator 113 of the head body 11, which is the liquid discharge section, and a second temperature control channel 1312 for cooling the drive IC 142, which is a heat-generating element, via a manifold unit 12 and a temperature control channel unit 13. Temperature-controlled water supplied from the second temperature-controlled water supply pipe 133 passes through the first temperature control channel 1213 and the second temperature control channel 1312 and is discharged from the second temperature-controlled water discharge pipe 134. The temperature-controlled water flowing through the first temperature control channel 1213 controls the temperature of the actuator 113, and the temperature-controlled water flowing through the second temperature control channel 1312 cools the drive IC 142.

[0079] The liquid discharge head 1 can cool the drive IC 142, which is a heat-generating element, via the second temperature control channel 1312, thereby suppressing heat-related damage to components around the drive IC 142. Furthermore, the liquid discharge head 1 can adjust (control) the temperature of the actuator 113 via the first temperature control channel 1213, thereby suppressing a decrease in printing accuracy due to heat.

[0080] Furthermore, the temperature control flow path unit 13 is configured such that the thermal conductivity of the temperature control manifold 1314, which has a flow path section 13121 that receives heat from the drive IC 142, is higher than that of the temperature control block 1316. As a result, the temperature control flow path unit 13 can efficiently transfer heat from the drive IC 142 to the temperature-controlled water via the flow path section 13121. In addition, the temperature control flow path unit 13 can suppress the transfer of heat from the drive IC 142 that has been transmitted to the flow path section 13121 to the temperature control block 1316. Therefore, since the temperature control block 1316 is not heated by the heat from the drive IC 142, the temperature of the temperature-controlled water that is branched at the temperature control block 1316 and flows to the first temperature control flow path 1213 is not raised by the heat from the drive IC 142.

[0081] Furthermore, the manifold unit 12 forming the first temperature control channel 1213 is in contact only with the temperature control channel unit 13 forming the second temperature control channel 1312, and with the temperature control block 1316 forming the branching and merging points of the first temperature control channel 1213 and the second temperature control channel 1312. Therefore, heat transfer from the drive IC 142 to the manifold unit 12 is via the temperature control block 1316, which has low thermal conductivity, further suppressing the transfer of heat from the drive IC 142 to the manifold unit 12. In addition, the manifold unit 12 and the temperature control channel unit 13 are connected by pipes 125, 126, and 13161. This makes it possible to minimize the cross-sectional area of ​​the heat transfer material (pipe) between the manifold unit 12 and the temperature control channel unit 13, further suppressing the transfer of heat from the drive IC 142 to the manifold unit 12 (actuator 113).

[0082] As described above, according to the embodiment of the liquid discharge head 1, the thermal conductivity of the temperature control block (forming part) 1316 that forms the branching and merging points is lower than that of the temperature control manifold (heat transfer part) 1314. Therefore, the liquid discharge head 1 suppresses the transfer of heat generated by the drive IC (heating element) 142 to the actuator 113, and can suitably control the temperature of the actuator 113 and the drive IC 142.

[0083] It should be noted that the embodiments of the present invention are not limited to the configurations described above. For example, in the example described above, the temperature control manifold 1314 is made of a metal material, and the cover 1315, temperature control block 1316, and temperature control water top plate 132 are made of a resin material with a lower thermal conductivity than the temperature control manifold 1314. However, the invention is not limited to this. That is, the thermal conductivity of the heat transfer part that contacts the drive IC 142 may be lower than the thermal conductivity of the forming part that forms the branching and confluence points of the temperature control water. However, it is preferable that the members interposed between the temperature control manifold 1314, which is the heat transfer part, and the temperature control block 1316 that forms the branching and confluence points, and the members interposed between the temperature control block 1316 and the members of the manifold unit 12 that transfer heat to the actuator 113, have a lower thermal conductivity than the heat transfer part.

[0084] Furthermore, the above example describes a configuration in which the piping 13161 provided in a pair of temperature control blocks 1316 is connected to the first temperature-controlled water supply pipe 125 and the first temperature-controlled water discharge pipe 126, which are piping provided in the manifold unit 12, but the configuration is not limited to this. For example, the temperature control block 1316 may not have the piping 13161, and the first temperature-controlled water supply pipe 125 and the first temperature-controlled water discharge pipe 126, which are piping for temperature-controlled water provided in the manifold unit 12, may be directly connected to the temperature control block 1316.

[0085] Furthermore, although the example described above illustrates a liquid discharge head 1 with four rows of nozzles, it is not limited to this configuration. For example, the liquid discharge head 1 may have three sets of head bodies 11 and a configuration with six rows of nozzles. In such a case, a pair of single-row temperature control flow channels 13122 are provided at both ends in the direction of nozzle arrangement (second direction Y), and two (a pair) of multi-row temperature control flow channels 13123 are provided between the pair of single-row temperature control flow channels 13122.

[0086] Furthermore, although the above example describes a case in which the surface of the drive IC 142 is in direct contact with the outer surface of the flow channel 13121, the example is not limited to this. For example, the drive IC 142 may be configured to contact the outer surface of the flow channel 13121 via a sheet-like, tape-like, gel-like, liquid-like member made of a material with high thermal conductivity.

[0087] According to at least one embodiment described above, by making the thermal conductivity of the branching point forming section that branches the first temperature adjustment channel and the second temperature adjustment channel lower than the thermal conductivity of the heat transfer section that contacts the heating element, it is possible to suppress the transfer of heat generated by the heating element to the actuator.

[0088] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. [Explanation of Symbols]

[0089] 1...Liquid ejection head, 11...Head body, 12...Manifold unit (first temperature control channel forming member), 13...Temperature control channel unit (second temperature control channel forming member), 14...Circuit board, 15...Cover, 111...Base plate, 112...Frame, 113...Actuator, 114...Nozzle plate, 115...Mask plate, 116...Common liquid chamber, 121...Manifold, 122...Top plate, 123...Ink supply Tube, 124...Ink discharge tube, 125...First temperature-controlled water supply tube (piping), 126...First temperature-controlled water discharge tube (piping), 127...Damper, 128...Bypass channel, 131...Temperature control channel section, 132...Top plate for temperature-controlled water, 133...Second temperature-controlled water supply tube, 134...Second temperature-controlled water discharge tube, 141...Wiring film, 142...Drive IC (heating element), 143...Printed circuit board, 1111...Supply port, 1112...Discharge port, 1131...Pressure chamber, 1133 ...wall, 1141...nozzle hole, 1142...nozzle row, 1151...window, 1161...first common liquid chamber, 1162...second common liquid chamber, 1163...third common liquid chamber, 1211...supply path, 1212...discharge path, 1213...first temperature control path, 1214...first manifold, 1215...second manifold, 1311...branch path, 1312...second temperature control path, 1313...merging path, 1314...temperature control manifold (heat transfer section), 1 315...cover, 1316...temperature control block (forming section, branching point forming section, confluence point forming section), 1316...temperature control block, 12111...ceiling section, 13121...flow channel section (heat transfer section), 13122...single-row temperature control flow channel section, 13123...multiple-row temperature control flow channel section, 13141...opening, 13142...groove, 13151...opening, 13161...piping, 13162...rib, 13163...groove, 131221...flow channel, 131231...flow channel.

Claims

1. A nozzle plate in which a nozzle hole for discharging liquid is formed, An actuator that changes the volume of the pressure chamber from which the liquid is discharged, A flow channel member that forms a flow channel for supplying the liquid to the actuator, A first temperature control channel forming member that forms a first temperature control channel for controlling the temperature of the actuator, A drive IC for driving the actuator, The system includes a second temperature control channel forming member that forms a second temperature control channel for suppressing the temperature rise of the drive IC, The second temperature control channel forming member has a heat transfer section through which heat from the drive IC is transferred, and a forming section that forms the branching and merging points of the first temperature control channel and the second temperature control channel. The forming part is a liquid dispensing head with a lower thermal conductivity than the heat transfer part.

2. The liquid discharge head according to claim 1, wherein the first temperature control channel forming member and the second temperature control channel forming member are in contact at the forming portion.

3. The heat transfer section is formed from a metal material. The liquid dispensing head according to claim 2, wherein the formed portion is made of a resin material.

4. The liquid discharge head according to claim 3, wherein the second temperature control flow path forming member comprises a temperature control manifold having the heat transfer portion, a cover covering the temperature control manifold, and a pair of temperature control blocks, which are the forming portion, provided on the cover.

5. The liquid discharge head according to claim 4, wherein the temperature control block and the first temperature control flow path forming member are connected by piping.

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