Liquid discharge head and liquid discharge device

Abstract

To provide a liquid discharge head which can displace a valve member stably, and to provide a liquid discharge device.SOLUTION: A liquid discharge head includes: nozzles for discharging a liquid; a needle valve 8 serving as a valve member which opens or closes the nozzles; and a moving mechanism which moves the needle valve 8 between an open position where the needle valve 8 opens the nozzles and a closed position where the needle valve 8 closes the nozzles. The moving mechanism includes: an actuator; and an arm member 3 having a connection part connected to the actuator, and a contact part 3a which contacts with the needle valve 8 and rotatably supported. An inner peripheral surface of a through hole 3b forming an arm side surface, which faces an outer peripheral surface of the needle valve 8 along a moving direction (a Z direction) of the needle valve, of the arm member 3 faces the outer peripheral surface of the needle valve while forming a predetermined gap d1 therebetween.SELECTED DRAWING: Figure 14

Description

Technical Field

[0001] The present invention relates to a liquid ejection head and an apparatus for ejecting a liquid.

Background Art

[0002] Conventionally, a liquid ejection head having a nozzle for ejecting a liquid, a valve member for opening and closing the nozzle, and a moving mechanism for moving the valve member between an open position for opening the nozzle and a closed position for closing the nozzle is known.

[0003] Patent Document 1 describes, as the above liquid ejection head, one including a lever that rotates with the displacement of an actuator, and a push rod that is fixed to one end of the lever and pushes a valve element for opening and closing the nozzle into the nozzle. The push rod is supported by a housing so as to be movable in the moving direction of the valve element, and the valve element is biased in a direction away from the nozzle by a coil spring. When the lever rotates due to the displacement of the actuator, the push rod moves in a direction away from the nozzle, the valve element moves to an open position for opening the nozzle by the biasing force of the coil spring, and droplets are ejected from the nozzle.

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in Patent Document 1, there is a possibility that a valve member such as a valve element cannot be displaced stably.

Means for Solving the Problems

[0005] In order to solve the above-described problems, the present invention provides a liquid discharge head having a nozzle for discharging a liquid, a valve member for opening and closing the nozzle, and a moving mechanism for moving the valve member between an open position for opening the nozzle and a closed position for closing the nozzle. The moving mechanism includes an actuator, and an arm member that is rotatably supported and has a connecting portion connected to the actuator and a contact portion that contacts the valve member. An arm side surface of the arm member that faces an outer peripheral surface of the valve member along the moving direction of the valve member has a predetermined gap and faces the outer peripheral surface.

Effects of the Invention

[0006] According to the present invention, the valve member can be stably displaced.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

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Figure 17

Figure 18

Figure 19

Figure 20

Figure 21

Mode for Carrying Out the Invention

[0008] Hereinafter, the best mode for carrying out the present invention will be described with reference to the drawings. It should be noted that those skilled in the art can easily make changes and modifications to the present invention within the scope of the claims to form other embodiments, and these changes and modifications are included in the scope of the claims. The following description is an example of the best mode in the present invention and does not limit the scope of the claims.

[0009] FIG. 1 is an external perspective view of the liquid ejection head 10 according to the present embodiment. In the following description, the nozzle arrangement direction (longitudinal direction of the liquid ejection head) is defined as the X direction, the liquid ejection direction from the nozzle (height direction of the liquid ejection head) is defined as the Z direction, and the direction orthogonal to both the X direction and the Z direction (lateral direction of the liquid ejection head) is defined as the Y direction for explanation.

[0010] The liquid ejection head 10 has a nozzle plate 14, a flow path member 15, and a cover 11 serving as a housing member. A supply port 12 for supplying liquid is provided at one end of the flow path member 15 in the X direction, and a discharge port 13 for discharging liquid is provided at the other end of the flow path member 15 in the X direction. Further, a harness passage hole 16 through which a harness for communicating with the actuator 2 housed in the cover is passed is provided in the upper part of the cover 11.

[0011] The nozzle plate 14, the flow path member 15, and the cover 11 are made of metal, resin, or ceramics. The cover 11 houses and supports a liquid ejection module 1 (see FIG. 4) described later inside. The flow path member 15 defines a flow path through which liquid flows, and the nozzle plate 14 has a plurality of nozzles for ejecting liquid. The nozzle plate 14 is mechanically (removably) fixed to the flow path member 15, and the cover 11 is mechanically (removably) fixed to the flow path member 15.

[0012] FIG. 2 is a diagram for explaining an example of the nozzle arrangement of the nozzle plate 14. As shown in FIG. 2(a), one nozzle row can be provided at the center of the nozzle plate in the Y direction (the short side direction of the head), or as shown in FIG. 2(b), the nozzles 14a can be arranged in a staggered pattern to provide two nozzle rows in the Y direction. Note that the nozzle arrangement shown in FIG. 2 is an example. For example, a configuration in which two sets of two nozzle rows are arranged in a staggered pattern in the Y direction, having a total of four nozzle rows, or a configuration in which a plurality of nozzle rows with the same position of the nozzles in the X direction (the long side direction of the head) are provided may also be used. The liquid ejection head of the embodiment described below has the nozzles 14a shown in FIG. 2(b) arranged in a staggered pattern and has two nozzle rows in the Y direction.

[0013] FIG. 3 is a diagram for explaining the mechanical fixing between the nozzle plate 14 and the flow path member 15. (a) is a schematic configuration diagram of the nozzle plate 14, and (b) is a schematic configuration diagram of the flow path member 15. At both ends of the nozzle plate 14 in the Y direction, five through holes 14b through which screws pass are provided at equal intervals in the X direction. Further, at both ends of the nozzle plate 14 in the X direction, positioning holes 14c for positioning the nozzle plate 14 on the flow path member 15 are provided. The positioning hole 14c on one end side in the X direction is the main reference for positioning and is a round hole having substantially the same diameter as the diameter of the positioning pin. The positioning hole 14c on one end side in the X direction is the secondary reference for positioning and has an elongated hole shape that is long in the X direction.

[0014] As shown in FIG. 3(b), the flow path member 15 has a flow path 5 through which a liquid flows. On the lower surface of the flow path member 15, a seal member 15a made of an elastic member such as rubber provided so as to surround the flow path is provided. Further, at both ends of the lower surface of the flow path member 15 in the Y direction, five female screw portions 15b having screw grooves provided on the inner peripheral surface are provided at equal intervals in the X direction. Further, at both ends in the X direction, pin fitting holes 15c into which positioning pins are fitted are provided. Note that positioning pins may be directly formed on the flow path member 15.

[0015] First, the positioning pin fitted into the pin fitting hole 15c of the flow path member 15 is inserted into the positioning hole 14c of the nozzle plate 14 to position the nozzle plate 14 with respect to the flow path member 15. Then, screws are inserted into the respective through holes 14b of the nozzle plate 14, and the screws are screwed into the female screw portions 15b of the flow path member 15, whereby the nozzle plate 14 is mechanically (removably) fixed to the flow path member 15. Further, when the screws are tightened, the seal member 15a provided on the flow path member 15 is crushed by the nozzle plate 14, so that the seal member 15a is in close contact with the nozzle plate, and the space between the nozzle plate 14 and the flow path member 15 is sealed.

[0016] In the present embodiment, since the nozzle plate 14 is fixed to the flow path member 15 by screwing, the nozzle plate 14 can be easily removed by removing the screws, and the nozzle plate can be easily replaced. Thereby, for example, it is possible to replace the nozzle plate with a nozzle plate having a nozzle diameter that provides optimal discharge characteristics for the discharge target on which the liquid is discharged.

[0017] FIG. 4 is a cross-sectional view taken along line A-A of FIG. 1, and FIG. 5 is a partial detailed view of the liquid discharge module 1. In the accommodation portion 11a of the cover 11, a plurality of liquid discharge modules 1 provided corresponding to the respective nozzles 14a are accommodated in a staggered two-row arrangement. Each liquid discharge module 1 includes a needle valve 8 that is a valve member for opening and closing the nozzle 14a, and a moving mechanism 6 having an arm member 3 and an actuator 2.

[0018] The plurality of liquid discharge modules 1 are arranged in a staggered manner in the X direction within the accommodation portion 11a of the cover 11 so that the needle valve 8 sides face each other in two rows (see also FIG. 8). Further, as shown in FIG. 4, the plurality of liquid discharge modules 1 are arranged such that a part of the arm member 3 overlaps when viewed from the X direction. Here, although the case where the nozzles 14a are arranged in a two-row staggered pattern on the nozzle plate 14 as shown in FIG. 2(b) has been described, even when the nozzles 14a are arranged in a single row on the nozzle plate 14 as shown in FIG. 2(a), the plurality of liquid discharge modules 1 are arranged such that a part of the arm member 3 overlaps when viewed from the X direction.

[0019] Here, the term "staggered arrangement of the liquid discharge modules" can also be described as a state in which a liquid discharge module having the actuator 2 located on one side of the nozzle arrangement and a liquid discharge module 1 having the actuator 2 located on the other side of the nozzle arrangement are arranged to face each other, and are arranged along the nozzle arrangement direction such that a part of the arm member 3 overlaps when viewed from the nozzle arrangement direction.

[0020] The actuator 2 is composed of a piezoelectric element 2a and a holder 2b that serves to apply and fix a preload for compressing the piezoelectric element 2a. The holder 2b is fixed to the inner wall surface of the housing portion 11a of the cover 11 that is perpendicular to the Y direction. More specifically, the holder 2b fixes the end portion of the piezoelectric element 2a in the Z direction, which is the direction in which the piezoelectric element 2a expands and contracts, to the inner wall surface of the housing portion 11a. The fixing method is performed by mechanical fixing using screws or the like, or chemical fixing such as bonding with an adhesive or thermal diffusion.

[0021] The arm member 3 has a support shaft 4, and the support shaft 4 is freely supported by the apparatus main body via a bearing. Rotation One end of the arm member 3 has a connection portion connected to the actuator 2, and the other end has a contact portion 3a that contacts an arm receiving portion 8c fixed to the needle valve 8. The contact portion 3a that contacts the arm receiving portion 8c at the other end of the arm member 3 is hemispherical and protrudes toward the arm receiving portion 8c side, or is semi-circular when viewed from the X direction, and is configured to smoothly contact the arm receiving portion 8c when the arm member 3 rotates.

[0022] In addition, a through hole 3b, which is a through portion through which the needle valve 8 penetrates, is formed at the other end of the arm member 3. The inner diameter of the through hole 3b is larger than the outer diameter of the needle valve 8 so that the inner peripheral surface of the through hole 3b, which is the arm side surface, does not contact the outer peripheral surface of the needle valve when the arm member 3 rotates.

[0023] A plurality of valve through holes 11b through which the needle valves 8 corresponding to the respective nozzles 14a penetrate are provided in the bottom surface portion of the housing portion 11a of the cover 11. A seal member 19 such as an O-ring is provided at the end portion on the flow path member 15 side of the valve through hole 11b. In addition, a valve receiving portion 20, which is a regulating member that regulates movement in a direction orthogonal to the opening and closing direction of the needle valve 8 and slidably receives the needle valve 8, is provided on the side opposite to the end portion on the flow path member 15 side of the valve through hole 11b. Further, the end portion of the needle valve 8 on the side opposite to the nozzle plate side penetrates through the spring receiving plate 18. The needle valve 8 is held in a posture parallel to the Z direction by the seal member 19, the valve receiving portion 20, and the spring receiving plate 18.

[0024] A compression spring 7 as a biasing member is provided between an arm receiving portion 8c fixed to the needle valve 8 and a spring receiving plate 18, and biases the needle valve 8 toward the nozzle plate 14 via the arm receiving portion 8c.

[0025] By biasing the needle valve 8 toward the nozzle plate 14 with the compression spring 7, it is possible to stabilize the movement of the needle valve 8 between an open position where the nozzle of the needle valve 8 is opened and a closed position where the nozzle is closed. The spring receiving plate 18 is attached to a connecting member 17 fixed to the cover 11.

[0026] As shown in FIG. 4, the actuator 2 of each liquid discharge module 1 is connected to a drive control device 30 via a harness. The drive control device 30 includes a waveform generation circuit 31 which is a drive pulse generation unit and an amplifier circuit 32.

[0027] The waveform generation circuit 31 generates a drive pulse waveform described later, and the amplifier circuit 32 amplifies the voltage value to a required value. Then, the amplified voltage signal is applied to the actuator 2. By applying this voltage, the drive control device 30 controls the displacement of the piezoelectric element 2a and controls the opening and closing of the nozzle 14a of the needle valve 8. Thereby, the discharge of the liquid from the liquid discharge head 10 is controlled. However, when the waveform generation circuit 31 can apply a voltage of a sufficient value, the amplifier circuit 32 may be omitted.

[0028] In the present embodiment, it has a normally closed configuration, and when no signal is supplied from the drive control device 30 to the actuator 2, the needle valve 8 closes the nozzle 14a by the biasing force of the compression spring 7. Here, as the situation where no signal is supplied to the actuator 2, it may be either a situation where a constant voltage of 0 or a constant static voltage is always applied.

[0029] The waveform generation circuit 31 generates drive pulses, which are waveforms representing the voltage applied to the actuator 2 over time. The waveform generation circuit 31 receives print data, for example, from an external PC or a microcontroller inside the device, and generates drive pulses based on this input data. The waveform generation circuit 31 can change the voltage applied to the actuator 2 and generate multiple drive pulses. As described above, when the waveform generation circuit 31 generates drive pulses, the piezoelectric element 2a of the actuator 2 expands and contracts according to the drive pulses.

[0030] Specifically, when a predetermined voltage is applied to the piezoelectric element 2a, the piezoelectric element 2a expands. When the piezoelectric element 2a expands, the other end of the arm member 3 rotates in a direction to lift the arm receiving portion 8c. As a result, the arm receiving portion 8c rises (moves toward the spring receiving plate 18) against the biasing force of the compression spring 7, and the needle valve 8 rises together with the arm receiving portion 8c. Thereby, the nozzle 14a is opened, and droplets are ejected from the nozzle 14a due to the pressure applied to the liquid in the flow path 5.

[0031] When the voltage applied to the piezoelectric element 2a decreases, the piezoelectric element 2a contracts. When the piezoelectric element 2a contracts, the other end of the arm member 3 rotates so as to move downward (toward the nozzle plate side). Then, the arm receiving portion 8c descends following the movement of the other end of the arm member 3 by the biasing force of the compression spring 7, the nozzle 14a is closed by the needle valve 8, and the ejection of droplets from the nozzle 14a stops.

[0032] In this embodiment, a piezoelectric element 2a is used as the actuator 2. However, as the actuator 2, other electrically driven devices such as a solenoid or a pneumatic drive piston equipped with a solenoid valve may be used. Also, in this embodiment, a compression spring 7 is used, but a tension spring that pulls the needle valve 8 toward the nozzle plate side may be used. In this case, for example, one end of the tension spring may be fixed to the bottom surface of the housing portion 11a, and the other end may be fixed to the needle valve 8 or the arm receiving portion 8c in an extended state.

[0033] Figure 6 is an enlarged view of the portion surrounded by the dashed line J in Figure 5. As shown in Figure 6, a sealing member 8a is provided at the tip of the needle valve 8. The sealing member 8a is made of any one of elastomer, hard rubber, metal, or ceramics. The needle valve 8 and the sealing member 8a may be formed as an integral part. Further, the flow path opening / closing portion 14d where the sealing member 8a of the sealing member 8a and the nozzle plate 14 comes into contact may be provided with a ceramic coating or a diamond-like coating to improve slidability and durability.

[0034] The tip of the sealing member 8a has a needle shape with a tapered cross-section, and the flow path opening / closing portion 14d of the nozzle plate 14 also has a mortar shape with a tapered cross-section. However, this is only an example, and the tip of the sealing member 8a may be a smooth convex surface such as a spherical shape, and the flow path opening / closing portion 14d of the nozzle plate 14 may be a smooth concave surface that closely adheres to the smooth convex surface of the tip of the sealing member 8a. Also, the tip of the sealing member 8a may be a flat surface, and the tip of the sealing member may be brought into contact with the periphery of the inlet of the nozzle 14a to close the nozzle 14a.

[0035] Also, the nozzle plate 14 may be a multilayer of a layer having the nozzle 14a and a layer having the flow path opening / closing portion 14d. In that case, each layer of the nozzle plate 14 has a structure for defining the position, and is firmly fixed by chemical fixing such as bonding by adhesion or joining by thermal diffusion so that liquid does not leak between the layers.

[0036] By providing the sealing member 8a at the tip of the needle valve 8, when the sealing member 8a is pressed against the flow path opening / closing portion 14d by the biasing force of the compression spring 7, the sealing member 8a closely adheres to the flow path opening / closing portion 14d, and the nozzle 14a can be surely closed.

[0037] Figure 7 is a schematic view showing a part of the B-B cross-section of Figure 4. As shown in FIG. 7, a connecting member 17 having a spring receiving plate 18 attached to its lower end extends in the X direction (the head longitudinal direction) of the cover 11 and is fixed so as to be bridged over a pair of inner wall surfaces perpendicular to the X direction of the cover 11.

[0038] When viewed from the arrangement direction (X direction) of the nozzles 14a in FIG. 4, the spring receiving plate 18 is provided between the actuator 2 located on one side (the left side in the figure) with respect to the arrangement of the nozzles 14a and the actuator 2 located on the other side (the right side in the figure). In the present embodiment, since the actuator 2 and the needle valve 8 are connected by the arm member 3, they are arranged so as to overlap each other when viewed from the moving direction (Z direction) of the needle valve 8. Therefore, in the present embodiment, the spring receiving plate 18 can be arranged in the space near the needle valve 8 above the needle valve 8 (above the Z axis in FIG. 4). By adopting such a configuration, the dimensions of the liquid ejection head in the Y direction and the Z direction can be reduced.

[0039] In the present embodiment, by having the arm member 3, the actuator 2, which is the largest component among the components constituting the liquid ejection module 1, can be arranged at the end side in the Y direction within the housing portion 11a. As a result, as shown in FIGS. 4 and 7, the connecting member 17 can be arranged at the center in the Y direction within the housing portion 11a, and the spring receiving plate 18 can be fixed by one connecting member 17. For example, when there is no arm member 3 and the actuator 2 is arranged at the center in the Y direction, it is necessary to hold both ends in the Y direction or both ends in the X direction of the spring receiving plate 18 by the connecting member 17 respectively. Thus, when the actuator 2 is arranged at the center in the Y direction, it is necessary to provide two connecting members 17, and there is a possibility that the liquid ejection head 10 may be enlarged in the X direction or the Y direction. Also, it is necessary to extend the spring receiving plate 18 to a position not facing the actuator 2, and the spring receiving plate 18 also becomes larger.

[0040] In contrast, in the present embodiment, by arranging one connecting member 17 at the center in the Y direction within the accommodating portion 11a, the spring receiving plate 18 can be held, and the size reduction of the liquid ejection head 10 can be achieved. Further, it is not necessary to extend the spring receiving plate 18 to a position where it does not face the actuator 2, and the size reduction of the spring receiving plate 18 can also be achieved. Furthermore, by providing the arm member 3 and arranging the actuator 2 at the end side in the Y direction within the accommodating portion 11a, the distance between nozzle rows (distance in the Y direction) can be shortened. As a result, the length of the spring receiving plate 18 in the Y direction can be further shortened, the material cost can be reduced, and the cost reduction of the liquid ejection head 10 can be achieved.

[0041] FIG. 8 is a schematic view showing a part of the C-C cross section of FIG. 4. In FIG. 8, illustration of the arm receiving portion 8c and the compression spring 7 is omitted. A group of liquid ejection modules 1 arranged on the upper side (one end side in the Y direction) of FIG. 8 corresponds to the nozzle rows arranged on the lower side (the other end side in the Y direction) of the nozzle plate 14 in FIG. 8. Also, a group of liquid ejection modules 1 arranged on the lower side (the other end side in the Y direction) of FIG. 8 corresponds to the nozzle rows arranged on the upper side (one end side in the Y direction) of the nozzle plate 14 in FIG. 8.

[0042] In the present embodiment, as shown in FIG. 4, the liquid ejection modules 1 are arranged alternately in the X direction such that a part of the arm member 3 overlaps when viewed from the X direction. As a result, when the length of the liquid ejection module 1 in the Y direction is L and the length of the accommodating portion 11a of the cover in the Y direction is D, D < 2L can be achieved. In this way, by overlapping a part of the arm member 3, the length D of the accommodating portion 11a of the cover in the Y direction can be made less than twice the length L of the liquid ejection module 1 in the Y direction, and the liquid ejection head 10 can be miniaturized in the Y direction. Note that the length L of the liquid ejection module 1 in the Y direction is the longer distance between the horizontal distance from the back surface of the actuator 2 fixed to the inner wall surface of the cover 11 to the end surface of the needle valve 8 in the Y direction (the direction in which the arm member 3 extends) or the horizontal distance from the actuator 2 of the arm member 3 to the outermost end surface.

[0043] Also, in the present embodiment, an arm member 3 is provided, and the actuator 2 is arranged at the end side in the Y direction within the housing portion 11a. As shown in FIG. 8, the width (length in the X direction) of the arm member 3 is narrower than the width (length in the X direction) of the actuator 2. Therefore, when the liquid discharge modules 1 are arranged alternately in the X direction, a part of the arm member 3 and the actuator 2 can be arranged so as to overlap with respect to the actuator 2 of the liquid discharge module arranged on the side opposite to the arrangement side of its own liquid discharge module 1 when viewed from the Y direction. As a result, the nozzle pitch d can be made shorter than the width W (length in the X direction) of the liquid discharge module (d < W), the nozzle pitch d can be narrowed, and the liquid discharge head 10 can be miniaturized in the X direction.

[0044] FIG. 9 is a perspective view of the liquid discharge module 1. The actuator 2 is composed of a piezoelectric element 2a and a holder 2b that holds the piezoelectric element 2a. The holder 2b has a fixed holder 21 and a biasing holder 22. A pair of side surfaces of the biasing holder 22 that are orthogonal to the Y direction have spring portions 22a. The biasing holder 22 sandwiches the piezoelectric element 2a in the Z direction with the biasing holder 22 and the fixed holder 21 and is fixed to the fixed holder 21 by adhesion or the like. The piezoelectric element 2a sandwiched between the biasing holder 22 and the fixed holder 21 is held by the holder 2b in a state of being compressed in the Z direction by the biasing force of the spring portion 22a of the biasing holder 22. Thereby, the piezoelectric element 2a is firmly housed in the holder 23, and the piezoelectric element 2a is stable with respect to the movement in its expansion and contraction direction (displacement in the Z direction).

[0045] In this embodiment, the pushing-in amount of the piezoelectric element 2a toward the nozzle side can be adjusted through a biasing receiver 24 that abuts on the upper surface of the piezoelectric element 2a by a pressing element such as a set screw built into the fixed holder 21. Further, the pressing element corrects the dimensional variation of the piezoelectric element 2a in the expansion and contraction direction (Z direction) by adjusting the position of the piezoelectric element 2a in the expansion and contraction direction. By adjusting the pushing-in amount of the piezoelectric element 2a with the pressing element, the spring portion 22a expands and contracts, and the biasing force (compressive force) applied to the piezoelectric element 2a is adjusted. The biasing holder 22 is formed by processing a sheet metal made of a highly durable metal such as SUS. The spring portion 22a is formed by providing slits so as to be alternately crank-shaped from the X direction, and can be formed by, for example, wire EDM (discharge) processing.

[0046] One end of the arm member 3 is connected to the bottom surface of the biasing holder 22. The spring portion 22a of the biasing holder 22 expands and contracts following the expansion and contraction of the piezoelectric element 2a in the Z direction, thereby pushing and pulling one end of the arm member 3 and rotating the arm member 3.

[0047] FIG. 10 is a perspective view of the liquid ejection module 1 showing a modification of the holder 2b of the actuator 2. As shown in FIG. 10, the holder 2b of this modification has a holder body 25, a lid member 26, a holder spring 27, and an actuator lever 28. The lid member 26 is fixed to the holder body 25 by a fastening member such as a screw, and the piezoelectric element 2a, the holder spring 27, and the actuator lever 28 are accommodated in the holder body.

[0048] The actuator lever 28 has an element contact portion 28b that contacts the lower surface of the piezoelectric element 2a and a pin-shaped arm connection portion 28a that penetrates a hole provided in the bottom of the holder body 25 and is connected to one end of the arm member 3. The element contact portion 28b and the arm connection portion 28a are connected by a plate-shaped connecting side surface portion 28c that faces the holder spring 27 from the Y direction.

[0049] The holder spring 27 is a coil spring. Its upper end abuts against the element contact portion of the actuator lever 28, and its lower end abuts against a spring receiver provided on the holder body 25 and is accommodated in the holder body in a compressed state. Thereby, the piezoelectric element 2a receives the biasing force of the holder spring 27 via the element contact portion 28b and is held in the holder body in a state of being sandwiched and compressed between the element contact portion 28b and the lid member 26. Therefore, also in the holder of this modification 2, the piezoelectric element 2a is firmly accommodated, and the piezoelectric element 2a is stable with respect to its movement in the expansion and contraction direction (displacement in the Z direction).

[0050] The components (such as the holder 2b and the actuator lever 28) around the piezoelectric element 2a of the actuator 2 shown in FIGS. 9 and 10 are formed of aluminum, copper, SUS304, etc. The thermal expansion coefficients of these surrounding components are about 17 (×10 -6 / °C or more), and they are made of materials with high thermal conductivity.

[0051] When the piezoelectric element 2a operates at a high duty cycle, it can generate significant heat. Also, the piezoelectric element 2a has the property of shrinking due to a temperature rise. By forming the components (such as the holder 2b and the actuator lever 28) around the piezoelectric element 2a of a material with high thermal conductivity, the heat dissipation of the piezoelectric element 2a can be promoted. Thereby, it is possible to allow the piezoelectric element 2a to operate consistently over a wide temperature range and to operate with a more active waveform at a higher frequency.

[0052] When the needle valve 8 is in the closed position where it closes the nozzle 14a, the compression spring 7 needs to bias the arm receiving portion 8c so that the load of the sealing member 8a at the tip of the needle valve 8 against the nozzle 14a is equal to or greater than the load at which no liquid leaks from the nozzle 14a. Further, the sealing member 19 receives a force in a direction away from the nozzle 14a due to the pressure of the liquid in the flow path 5. As a result, a force acts on the needle valve 8 in a direction away from the nozzle 14a. Therefore, the biasing force of the compression spring 7 needs to exceed the resultant force of the above load and the force in the direction of separating the needle valve 8 from the nozzle 14a by the sealing member 19, and thus the biasing force of the compression spring 7 increases. Also, in the present embodiment, as will be described later, the displacement of the actuator 2 is amplified by the arm member 3 to move the needle valve 8. Therefore, the force required to move the needle valve 8 to the open position against the biasing force of the compression spring 7 is amplified by the arm member 3. Therefore, the actuator 2 is designed such that the piezoelectric element 2a and the holder 2b that restrains the piezoelectric element 2a can obtain a generating force capable of moving the needle valve against the biasing force of the compression spring 7 amplified by the arm member 3.

[0053] Next, the arm member 3, which is a characteristic part of the present embodiment, will be described in detail. FIG. 11 is a schematic view showing the arm member 3 of the present embodiment. (a) is a cross-sectional view of the arm member 3 as viewed from the X direction, and (b) is a view of the arm member 3 as viewed from the Z direction (nozzle side). The arm member 3 of the present embodiment has a connection portion 3d to which the actuator 2 is adhesively fixed on one end side, and a contact portion 3a that contacts the arm receiving portion 8c on the other end side. Further, a support shaft 4 is provided on the connection portion 3d side rather than at the center in the longitudinal direction (Y direction) of the arm member 3.

[0054] As described above, the contact portion 3a protrudes in the direction opposite to the liquid ejection direction (-Z direction), and the contact surface that contacts the arm receiving portion 8c has an arc shape as viewed from the X direction, as shown in FIG. 11(a). Further, as shown in FIG. 11(b), a through hole 3b through which the needle valve 8 penetrates is provided at the center of the contact portion 3a. As described above, the inner diameter of the through hole 3b is larger than the outer diameter of the needle valve 8, and a gap d1 is formed between the inner peripheral surface of the through hole 3b as the arm side surface and the outer peripheral surface of the needle valve 8 so that the needle valve 8 does not contact the arm member 3 when the arm member 3 rotates. As shown in FIG. 14, the gap d1 is wider than the gap d2 between the valve receiving portion 20 and the outer peripheral surface of the needle valve 8.

[0055] The connecting portion 3d is composed of a rectangular adhesive surface portion 3d1 perpendicular to the Z direction and a deformable connecting portion 3d2 extending in the Z direction that connects the adhesive surface portion 3d1 and the main body 3f of the arm member 3. As shown in FIG. 11(a), the connection point S of the connecting portion 3d2 with the main body 3f of the arm member is the same as the center O1 of rotation of the arm member 3 in the Z direction. Thereby, a straight line A2 passing through the center O1 of rotation of the arm member 3 and the connection point S of the connecting portion 3d2 is orthogonal to the displacement direction A1 of the actuator 2.

[0056] When the straight line A2 passing through the center O1 of rotation of the arm member 3 and the connection point S of the connecting portion 3d2 is not orthogonal to the displacement direction A1 of the actuator 2 in the state where the actuator 2 is OFF, the pressing force on the arm member due to the displacement of the actuator 2 is as follows. That is, the pressing force is divided into a vector component that rotates the arm member in a direction orthogonal to the straight line A2 passing through the center O1 of rotation and the connection point S of the connecting portion 3d2, and a vector component in the direction of the straight line A2. As a result, not all of the pressing force of the actuator 2 can be used as a force to rotate the arm member 3.

[0057] On the one hand, when a straight line A2 passing through the rotation center O1 of the arm member 3 and the connection point S of the connection portion 3d2 is orthogonal to the displacement direction A1 of the actuator 2 as in the present embodiment, all of the pressing force on the arm member due to the displacement of the actuator 2 can be used as the force for rotating the arm member 3. As a result, the displacement of the actuator 2 can be efficiently used for the rotation of the arm member 3, and the arm member 3 can be rotated well against the biasing force of the compression spring 7.

[0058] In addition, if the difference in the Z direction (actuator displacement direction) of the connection point S of the connection portion 3d2 with respect to the rotation center of the arm member 3 of the arm member 3 is as follows, the vector component in the direction of the straight line A2 is also small, and the arm member 3 can be rotated well. That is, the difference in the Z direction (actuator displacement direction) of the connection point S with respect to the rotation center O1 of the arm member 3 is configured to be smaller than the displacement amount of the piezoelectric element 2a.

[0059] The actuator 2 is adhesively fixed to the adhesive surface portion 3d1 of the arm member 3. In this way, by providing the rectangular adhesive surface portion 3d1 perpendicular to the Z direction on the arm member 3, the adhesive area with the piezoelectric element 2a becomes large, and the piezoelectric element 2a can be firmly fixed. In addition, the influence on the displacement due to the variation in the adhesive position of the piezoelectric element 2a can be suppressed.

[0060] When the adhesive surface portion 3d1 is displaced in the Z direction together with the actuator 2 due to the displacement of the actuator 2, the arm member 3 rotates with the support shaft 4 as a fulcrum. Due to the rotation of the arm member 3, a force is generated to tilt the left end of the adhesive surface portion 3d1 in FIG. 11(a) upward. At this time, the connection portion 3d2 configured to be flexible is flexibly deformed to absorb the tilting force, and the arm member 3 can be smoothly rotated. As a result, the needle valve 8 can be stably displaced, and variations in droplets and the like can be suppressed.

[0061] In addition, in the arm member 3 of the present embodiment, the support shaft 4 is provided on the connection portion 3d side rather than at the center in the longitudinal direction (Y direction) of the arm member 3 (the longitudinal distance L2 from the support shaft 4 to the connection portion 3d is shorter than the distance L1 from the support shaft 4 to the contact portion 3a). As a result, the rotation radius of the contact portion 3a becomes longer than the rotation radius of the connection portion 3d, and the displacement amount of the contact portion 3a in the Z direction becomes larger than the displacement amount of the connection portion 3d in the Z direction. As a result, the displacement amount by which the contact portion 3a lifts the arm receiving portion 8c becomes larger than the displacement amount in the Z direction of the actuator 2. As a result, the displacement amount of the actuator 2 is amplified by the arm member 3, and the movement amount of the needle valve 8 can be increased. Therefore, the gap between the nozzle 14a and the sealing member 8a when the needle valve 8 is in the open position can be increased, the high-viscosity liquid can easily flow into the nozzle 14a, and the size of the droplets ejected from the nozzle 14a can be increased. Therefore, the printing efficiency can be improved, and the printing time can be shortened. In addition, an actuator 2 with a small displacement amount can be used, the actuator 2 can be miniaturized, and the liquid ejection head 10 can be effectively miniaturized.

[0062] FIG. 12 is a diagram showing a main part configuration of a conventional arm member 3. As shown in FIG. 12, the needle valve 8 is fitted and fixed in a through hole 3j through which the needle valve 8 of the arm member 3 passes, and the inner peripheral surface of the through hole 3b and the outer peripheral surface of the needle valve 8 are in close contact. In such a configuration, when the arm member 3 rotates by the drive of the actuator, as shown in FIG. 12(b), the needle valve 8 moves in a direction away from the nozzle 14a while the upper end falls to the right side (arm member side) in the figure. As a result, as shown in FIG. 12(b), the needle valve 8 hits the valve receiving portion 20, inhibiting the movement of the needle valve 8 to the open position. In the worst case, the needle valve 8 may not move to the open position or the needle valve 8 may break.

[0063] Also, as shown in FIG. 13, when the contact portion that contacts the arm receiving portion 8c of the arm member 3 is a flat surface, when the actuator 2 is in the OFF state, as shown in FIG. 13(a), the lower surface of the arm receiving portion 8c is in surface contact with the contact portion of the arm member 3. As shown in FIG. 13(b), when a voltage is applied to the piezoelectric element 2a and the arm member 3 starts to rotate clockwise in the figure, the arm member 3 contacts on the left side of the arm receiving portion 8c in the figure. As a result, as shown in FIG. 13(c), the arm receiving portion 8c tends to tilt following the tilt of the arm member 3 by the biasing force of the compression spring 7, and the needle valve 8 fixed to the arm receiving portion 8c tilts together with the arm receiving portion 8c. As a result, there is a risk of hitting the through hole 3b of the arm member 3 or the valve receiving portion 20.

[0064] FIG. 14 is a schematic view showing the periphery of the contact portion of the arm member 3 of the present embodiment. FIG. 14(a) shows the periphery of the contact portion of the arm member 3 when the needle valve 8 is in the closed position, and FIG. 14(b) shows the periphery of the contact portion of the arm member 3 when the needle valve 8 is in the closed position. In the present embodiment, as described above, the inner diameter of the through hole 3b is made larger than the outer diameter of the needle valve 8, and a gap d1 is formed between the inner peripheral surface of the through hole 3b as the arm side surface and the outer peripheral surface of the needle valve 8. Thereby, when the arm member 3 rotates, it is possible to suppress the inner peripheral surface of the through hole 3b from hitting the needle valve 8 and to suppress the movement of the needle valve 8 to the open position from being inhibited. As a result, the needle valve 8 can be stably moved between the open position and the closed position, and droplets can be ejected from the nozzle 14a satisfactorily.

[0065] Further, in the arm member 3 of the present embodiment, the contact portion 3a protrudes in the direction opposite to the upper liquid discharge direction (-Z direction), and the contact surface that contacts the arm receiving portion 8c has an arc shape when viewed from the X direction. As shown in Fig. 14(a), before the arm member 3 rotates, the top of the contact portion 3a is in contact with the center of the arm receiving portion 8c in the left - right direction (Y - direction) in the figure. When the arm member 3 rotates, the contact position between the contact portion 3a and the arm receiving portion 8c shifts to the left side (the other - end side of the arm member) as shown in Fig. 14(b). At this time, since the contact surface between the contact portion 3a and the arm receiving portion 8c is arc - shaped when viewed from the X - direction, the contact position between the arm receiving portion 8c and the contact portion 3a hardly changes as the arm member 3 rotates. Therefore, the contact between the central portion of the arm receiving portion 8c in the left - right direction (Y - direction) in the figure is maintained. As a result, the arm receiving portion 8c can be suppressed from tilting in the Z - direction by the biasing force of the compression spring 7, and the needle valve 8 can be suppressed from hitting the inner peripheral surface of the through - hole 3b or the valve receiving portion 20. Thus, it is possible to prevent the movement of the needle valve 8 to the open position from being inhibited, and the needle valve 8 can be stably moved between the open position and the closed position, and droplets can be discharged well from the nozzle 14a. Here, the central portion where the contact portion 3a contacts the arm receiving portion 8c is preferably in the range from the center of the needle valve 8 to the outer diameter of the needle valve 8 when viewed from the X - direction. That is, by making the contact position between the arm receiving portion 8c and the contact portion 3a within the range of the outer diameter of the needle valve 8 when viewed from the X - direction (maintaining the contact with the central portion), the inclination of the needle valve 8 can be suppressed.

[0066] Also, by making the contact portion 3a an arc surface, the shift of the contact position between the contact portion 3a and the arm receiving portion 8c can be smoothly performed, and the arm member 3 can be smoothly rotated. As a result, the needle valve 8 can be stably displaced, and variations in droplets and the like can be suppressed.

[0067] Also, as shown in FIG. 11, the bottom surface 3fa of the main body 3f of the arm member 3 is a flat surface. The assembly of the liquid ejection module 1 is performed by placing the arm member 3 on the reference surface of a reference member such as a block gauge and setting the arm member 3 in the initial posture (the posture when the actuator is OFF). By making the bottom surface 3fa of the main body 3f a flat surface, it is possible to suppress the arm member 3 from tilting with respect to the reference surface when assembling the liquid ejection module 1. As a result, it is possible to suppress the arm member 3 from being tilted and assembled with respect to the target initial posture. Thereby, when the actuator 2 is in the OFF state, the above straight line A2 can be accurately assembled so as to be orthogonal to the displacement direction A1 of the actuator 2. In addition, it is possible to suppress the occurrence of a location where the gap between the inner peripheral surface of the through hole 3b and the outer peripheral surface of the needle valve 8 is narrow.

[0068] Also, the main body 3f of the arm member 3 is designed to have a sufficient sectional second moment with respect to the rotation direction of the arm member 3 so that it bends and deforms when the actuator 2 is displaced and no displacement loss occurs.

[0069] In the present embodiment, the arm member 3 is formed of SUS440. SUS440 is a martensitic stainless steel that hardens by quenching and tempering, and is excellent in strength, hardness, and wear resistance. Thus, by forming the material of the arm member with SUS440, which is excellent in strength and hardness, it is possible to have a sufficient sectional second moment with respect to the rotation direction of the arm member. In addition, by forming the material of the arm member with SUS440, which is excellent in strength, it is possible to increase the life of the connecting portion 3d2 that bends and deforms. The thermal expansion coefficient of this SUS440 is about 10 (×10 -6 / °C).

[0070] FIG. 15 is a diagram showing the displacement distribution in the Z direction of the arm member 3 of the present embodiment when the actuator 2 is driven. In FIG. 15, the darker the color, the greater the displacement in the Z direction. As shown in FIG. 15, by configuring the arm member 3 as described above, the arm member 3 can be rotated well, and a displacement distribution can be obtained in which the displacement in the Z direction increases as the distance from the center of rotation increases. Further, as can be seen from the displacement distribution in FIG. 15, the displacement amount in the Z direction on the contact portion side of the other end side of the arm member 3 is larger than that on the connection portion side of the one end side of the arm member 3, and it can be understood that the displacement of the actuator 2 is amplified by the arm member 3 to move the needle valve 8.

[0071] FIG. 16 is a schematic view showing a modified example of the arm member 3. (a) is a cross-sectional view of the arm member 3 as viewed from the X direction, and (b) is a view of the arm member 3 as viewed from the Z direction (nozzle side). In this modified example of the arm member 3, the through portion through which the needle valve 8 passes is a groove-shaped through groove 3g. Also in this modified example, the groove side surface as the arm side surface of the through groove 3g faces the outer peripheral surface of the needle valve 8 with a gap d1. Thereby, when the arm member 3 rotates due to the displacement of the actuator 2, it is possible to suppress the groove side surface from hitting the needle valve 8, and the needle valve 8 can be moved smoothly.

[0072] [Modified Example] FIG. 17 is a schematic view of a main part of a modified example of the liquid ejection head 10A. FIG. 17(a) is a view as viewed from the Z direction, and FIG. 17(b) is a cross-sectional view taken along line E-E of FIG. 17(a). Further, FIG. 18 is an enlarged view of the broken line G portion of FIG. 17. In this modified example of the liquid ejection head 10A, the needle valve 8 is configured to open and close a plurality of nozzles 14a. In this modified example, as shown in FIG. 17(a), on the nozzle plate 14, the nozzles 14a are arranged in a 2-row and 2-column configuration in which they are also arranged in the Y direction.

[0073] As shown in Fig. 17, the nozzle plate 14 is formed with a branch flow path 14f in which the flow path branches in two directions in the X direction from a flow path opening / closing portion 14d to which a sealing member 8a at the tip of the needle valve 8 is in close contact, and each flow path of the branch flow path 14f communicates with the nozzle 14a, respectively. Note that if the flow velocities of the droplets ejected from each nozzle 14a are approximately the same and the landing timings are synchronized well, the dimensions of each flow path of the branch flow path 14f and the diameters and depths of the plurality of nozzles 14a may be made different from each other. Also, if the landing timings are synchronized well, droplets may be ejected from three or more nozzles in one liquid ejection module.

[0074] In this modification, droplets can be ejected from a plurality of nozzles 14a in one liquid ejection module 1, the number of liquid ejection modules 1 can be reduced, and the cost of the apparatus can be reduced.

[0075] Also, in the modification, the nozzle pitch in the nozzle row can be reduced compared to the configuration in which one nozzle 14a is provided on the axis of the needle valve 8. Thereby, in one nozzle row, the same resolution in the X direction as that obtained when using two nozzle rows arranged in a staggered pattern can be obtained.

[0076] The liquid ejection head of the present embodiment is of the valve jet type, and can eject a highly viscous liquid or large droplets (with a diameter of several tens to several hundreds of μm) toward a distant ejection target (several tens of mm ahead). Also, the nozzle diameter can be increased, and a liquid containing a material with a large particle size can be ejected well. Thus, since a highly viscous liquid can be ejected, the liquid ejection head of the present embodiment is suitable for painting of vehicle bodies of cars and trucks, aircraft fuselages, building walls, road surfaces, etc., and printing of images. It can also be suitably used for forming electrodes such as lithium ion batteries mounted on vehicle bodies.

[0077] Next, an example of an apparatus for ejecting a liquid having the above-described liquid ejection head 10 will be described.

[0078] Fig. 19 is a schematic perspective view of an apparatus 100 for ejecting a liquid. The liquid ejecting device 100 includes a movable frame unit 120 that is installed to face the object to be ejected 200. The frame unit 120 includes a Y-axis rail 101 extending in the horizontal direction, a plurality of X-axis rails 102 extending in the vertical direction and provided at a predetermined interval, and a Z-axis rail 103 intersecting the X-axis rails 102 and the Y-axis rail 101.

[0079] Each X-axis rail 102 holds the Y-axis rail 101 so that the Y-axis rail 101 extending horizontally can move in the X direction (the nozzle arrangement direction of the liquid ejection head, which is the vertical direction). Further, the Y-axis rail 101 holds the Z-axis rail 103 so that the Z-axis rail 103 can move in the Y direction. And the Z-axis rail 103 holds the carriage 110 so that the carriage 110 can move in the Z direction.

[0080] The carriage 110 includes a head holder 130. The head holder 130 holds, for example, liquid ejection heads of different colors. For example, it holds a C-color liquid ejection head that ejects cyan paint, an M-color liquid ejection head that ejects magenta paint, a Y-color liquid ejection head that ejects yellow paint, and a K-color liquid ejection head that ejects black paint. Further, it may hold a W-color liquid ejection head that ejects white paint. Also, it may hold a liquid ejection head that ejects a clear (transparent) coating paint and perform coating simultaneously with printing.

[0081] Further, it includes a first Z-direction driving unit 140a that moves the carriage 110 in the Z direction (which is the liquid discharge direction and the approach / separation direction with respect to the discharge target 200) along the Z-axis rail 103. Also, it includes a Y-direction driving unit 150 that moves the Z-axis rail 103 in the Y direction (which is a direction orthogonal to both the liquid discharge direction of the liquid discharge head and the nozzle array direction, and is a horizontal direction) along the Y-axis rail 101. Further, it includes an X-direction driving unit 160 that moves the Y-axis rail 101 in the X direction (which is the nozzle array direction of the liquid discharge head and is a vertical direction) along the X-axis rail 102. The Y-axis rail 101 is supported by the X-direction driving unit 160 held on each Y-axis rail 101. Furthermore, it includes a second Z-direction driving unit 140b that moves the head holder 130 in the Z direction with respect to the carriage 110.

[0082] The apparatus 100 for discharging liquid discharges paint, which is an example of liquid, from a liquid discharge head provided on the head holder 130 while moving the carriage 110 in the directions of the X-axis, Y-axis, and Z-axis, and performs drawing on the liquid discharge target 200. Here, the movement of the carriage 110 and the head holder 130 in the Z direction does not need to be parallel to the Z direction, and may be an oblique movement as long as it includes at least a component in the Z direction. Also, when the nozzle row of the liquid discharge head is in a single row, the carriage 110 may be held so as to be tiltable with respect to the X direction of the liquid discharge head, and the nozzle pitch may be made variable.

[0083] FIG. 20 is a diagram showing an example of a supply device 170 that supplies paint, which is a liquid, to a plurality of liquid discharge heads 10 included in the apparatus 100 for discharging liquid. The supply device 170 includes tanks 172a to 172d as sealed containers that store the paints 171a to 171d discharged from the respective liquid discharge heads 10a to 10d held by the head holder 130.

[0084] The tank 172 and the supply port 12 (see FIG. 1) of the liquid ejection head 10 are connected via tubes 173, respectively. On the other hand, the tank 172 is connected to a compressor 176 via a pipe 175 including an air regulator 174. The compressor 176 supplies pressurized air to the tank 172. As a result, the paint in the liquid ejection head 10 is pressurized, and the paint is ejected from the nozzle 14a by opening the aforementioned needle valve 8.

[0085] In FIG. 19, the surface shape of the liquid ejection object 200 is shown as a flat surface, but the surface shape of the liquid ejection object 200 may be a surface close to vertical or a surface with a large radius of curvature, such as the body of a car, a truck, or an aircraft.

[0086] FIG. 21 is a diagram showing an example of an electrode manufacturing apparatus 700 as an apparatus for ejecting a liquid including the liquid ejection head of the present embodiment. The electrode manufacturing apparatus 700 includes an ejection process section 710 including a process of applying a liquid composition onto a printing substrate 704 having an ejection object to form a liquid composition layer, and a heating process section 730 including a process of heating the liquid composition layer to obtain an electrode composite layer.

[0087] The printing substrate 704 on which the liquid composition layer is formed is not particularly limited as long as it is an object for forming a layer having an electrode material, and can be appropriately selected according to the purpose. Examples thereof include an electrode substrate (current collector), an active material layer, and a layer having a solid electrode material.

[0088] In addition, the ejection process section 710 may be configured to form a layer having an electrode material by directly ejecting the liquid composition as long as it is possible to form a layer having an electrode material on the printing substrate 704. Also, it may be configured to form a layer having an electrode material by indirectly ejecting the liquid composition. The heating process section 730 is a process of heating the liquid composition ejected onto the printing substrate 704 in the ejection process section 710. The liquid composition layer can be dried by heating.

[0089] The electrode manufacturing apparatus 700 includes a conveyance unit 705 that conveys a printing substrate 704, and the conveyance unit 705 conveys the printing substrate 704 at a preset speed in the order of a discharge process unit 710 and a heating process unit 730. As a method for manufacturing the printing substrate 704 having a discharge object such as an active material layer, there is no particular limitation, and a known method can be appropriately selected. The discharge process unit 710 includes a printing apparatus 281a including the liquid discharge head 10 of the present embodiment that discharges a liquid composition onto the printing substrate 704. Further, it includes a storage container 281b that stores the liquid composition and a supply tube 281c that supplies the liquid composition stored in the storage container 281b to the printing apparatus 281a.

[0090] The storage container 281b stores the liquid composition 707, and the discharge process unit 710 discharges the liquid composition 707 from the printing apparatus 281a and applies the liquid composition 707 onto the printing substrate 704 to form a liquid composition layer in a thin film shape. Note that the storage container 281b may be configured to be integrated with the manufacturing apparatus for the electrode composite layer, or may be configured to be removable from the manufacturing apparatus for the electrode composite layer. Further, it may be a container used for adding to a storage container integrated with the manufacturing apparatus for the electrode composite layer or a storage container removable from the manufacturing apparatus for the electrode composite layer. Further, the storage container 281b and the supply tube 281c can be arbitrarily selected as long as they can stably store and supply the liquid composition 707.

[0091] The heating process unit 730 has a heating device 703 and includes a solvent removal step of heating and drying the solvent remaining in the liquid composition layer by the heating device 703 to remove it. Thereby, an electrode composite layer can be formed. The heating process unit 730 may perform the solvent removal step under reduced pressure.

[0092] There is no particular limitation on the heating device 703, and it can be appropriately selected according to the purpose. For example, substrate heating, an IR heater, a hot air heater, etc. can be mentioned, and these may be combined. Further, regarding the heating temperature and time, they can be appropriately selected according to the boiling point of the solvent contained in the liquid composition 707 and the formed film thickness.

[0093] When the liquid discharge head 10 of the present embodiment is used in the electrode manufacturing apparatus 700, the liquid composition can be discharged to the target position of the object to be discharged. The electrode mixture layer can be suitably used, for example, as a part of the configuration of an electrochemical element. There are no particular restrictions on the configuration other than the electrode mixture layer in the electrochemical element, and known ones can be appropriately selected, for example, a positive electrode, a negative electrode, a separator, and the like.

[0094] As described above, the embodiments of the present invention have been described. However, the present invention is not limited to the above-described embodiments, and it goes without saying that various modifications can be made without departing from the gist of the present invention.

[0095] In the above description, the example in which the drive control device 30 applies a voltage to a drive body such as the piezoelectric element 2a to open and close the needle valve 8 has been described. However, the present invention is not limited to this, and the needle valve 8 may be opened and closed by pneumatic pressure or hydraulic pressure. In this case, the drive pulse generated by the drive control device 30 is a drive waveform for driving with a pressure set by a pressurizing mechanism using pneumatic pressure or hydraulic pressure.

[0096] In the present application, the “device for discharging a liquid” includes a liquid discharge head or a liquid discharge unit in which functional parts and mechanisms are integrated with the liquid discharge head, and drives the liquid discharge head to discharge the liquid. The above integration includes, for example, those in which the liquid discharge head and the functional parts or mechanisms are fixed to each other by fastening, adhesion, engagement, etc., and those in which one is movably held with respect to the other. Further, the liquid discharge head and the functional parts or mechanisms may be detachable from each other.

[0097] As the liquid discharge unit, there are those in which the liquid discharge head and the head tank are integrated, and those in which both are connected to each other by a tube or the like and integrated. Here, it is also possible to add a unit including a filter between the liquid discharge head and the head tank of these liquid discharge units.

[0098] As the liquid ejection unit, there is one in which the liquid ejection head and the carriage are integrated, and one in which the liquid ejection head, the carriage, and the scanning movement mechanism are integrated. Also, as the liquid ejection unit, there is one in which the liquid ejection head is movably held by a guide member that constitutes a part of the scanning movement mechanism, and the liquid ejection head and the scanning movement mechanism are integrated.

[0099] As the liquid ejection unit, there is one in which a cap member that is a part of the maintenance and recovery mechanism is fixed to the carriage to which the liquid ejection head is attached, and the liquid ejection head, the carriage, and the maintenance and recovery mechanism are integrated. Also, as the liquid ejection unit, there is one in which a tube is connected to the liquid ejection head to which the head tank or the flow path component is attached, and the liquid ejection head and the supply mechanism are integrated. Through this tube, the liquid from the liquid storage source is supplied to the liquid ejection head.

[0100] The scanning movement mechanism shall include the guide member alone. The supply mechanism shall include the tube alone and the loading unit alone.

[0101] The "device for ejecting liquid" includes not only a device capable of ejecting liquid onto an object to which the liquid can adhere, but also a device for ejecting liquid into the air or into a liquid.

[0102] This "liquid ejection device" can also include means related to the feeding, conveying, and paper discharging of an object to which the liquid can adhere, as well as other pre-treatment devices, post-treatment devices, and the like.

[0103] For example, as the "device for ejecting liquid", there is an image forming device that ejects ink to form an image on paper, and a three-dimensional modeling device (3D modeling device) that ejects a modeling liquid onto a powder layer formed in layers of powder in order to model a three-dimensional object (3D object).

[0104] In addition, the "device for discharging liquid" is not limited to those in which a significant image such as characters or figures is visualized by the discharged liquid. For example, those that form a pattern having no meaning by itself, those that create a three-dimensional image, etc. are also included.

[0105] The above-mentioned "object to which liquid can adhere" refers to the object to which the liquid described above is discharged, and means an object to which the liquid can adhere at least temporarily, such as an object to which the liquid adheres and adheres firmly, an object to which the liquid adheres and penetrates, etc. Specific examples include recording media such as paper, recording paper, recording sheets, films, and cloth, electronic components such as electronic substrates and piezoelectric elements, powder layers (powder layers), organ models, media such as test cells, etc. and all objects to which liquid adheres are included unless otherwise particularly limited.

[0106] The material of the above-mentioned "object to which liquid can adhere" may be paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, ceramics, etc. as long as the liquid can adhere even temporarily.

[0107] In addition, as the "device for discharging liquid", there is a device in which the head unit and the object to which liquid can adhere move relative to each other, but it is not limited to this. Specific examples include a serial type device that moves the head unit and a line type device that does not move the head unit.

[0108] In addition, as the "device for discharging liquid", there are also a treatment liquid coating device that discharges a treatment liquid onto paper for the purpose of modifying the surface of the paper, etc., and an injection granulation device that injects a composition liquid in which raw materials are dispersed in a solution through nozzle holes to granulate fine particles of the raw materials.

[0109] What has been described above is an example, and each of the following aspects has a specific effect. (Aspect 1) In a liquid discharge head 10 having a nozzle 14a for discharging a liquid, a valve member such as a needle valve 8 for opening and closing the nozzle 14a, and a moving mechanism 6 for moving the valve member between an open position for opening the nozzle 14a and a closed position for closing the nozzle 14a, the moving mechanism 6 includes an actuator 2, and an arm member 3 that has a connection portion 3d connected to the actuator 2 and a contact portion 3a that contacts the valve member and is rotatably supported. An arm side surface (in this embodiment, the inner peripheral surface of the through hole 3b) of the arm member 3 that faces the outer peripheral surface of the valve member along the moving direction (Z direction) of the valve member has a predetermined gap and faces the outer peripheral surface. In Patent Document 1, as described above, a push rod movably supported in the moving direction of the valve element on the housing is fixed to a lever that rotates with the displacement of the actuator. Therefore, the push rod rotates together with the lever. As a result, there is a possibility that the push rod may not move smoothly in the displacement direction of the valve element, such as hitting against the housing. As a result, the valve element, which is a valve member that moves with the displacement of the push rod, may not move smoothly, and there has been a possibility that the valve member such as the valve element cannot be stably displaced. On the other hand, in Aspect 1, a predetermined gap is formed between the arm side surface of the arm member that rotates with the displacement of the actuator and faces the outer peripheral surface of the valve member along the moving direction of the valve member, and the outer peripheral surface of the valve member. Thereby, when the arm member rotates due to the displacement of the actuator, it is possible to suppress the arm side surface of the arm member from colliding with the outer peripheral surface of the valve member. Thereby, it is possible to prevent the movement of the valve member from being inhibited by the side surface of the arm member hitting against the outer peripheral surface of the valve member. As a result, the valve member can be moved smoothly, the valve member can be stably displaced, and droplets can be stably discharged from the nozzle.

[0110] (Aspect 2) In Aspect 1, a restricting member such as a valve receiving portion 20 for restricting the movement of a valve member such as the needle valve 8 in a direction orthogonal to the moving direction (Z direction) is provided, and the gap d1 between the arm side surface (the inner peripheral surface of the through hole 3b) and the outer peripheral surface is wider than the gap d2 between the restricting side surface of the restricting member facing the outer peripheral surface and the outer peripheral surface. According to this, as described in the embodiment, the gap d1 between the arm side surface (the inner peripheral surface of the through hole 3b) and the outer peripheral surface is smaller than the gap d2 between the regulating side surface facing the outer peripheral surface of a regulating member such as the valve receiving portion 20 and the outer peripheral surface. Thus, when the arm member rotates, it is possible to suppress the arm side surface from hitting the valve member.

[0111] (Aspect 3) In Aspect 1 or 2, a biasing member such as a compression spring 7 is provided that biases a contact portion 3a of the arm member 3 in the moving direction (Z direction) against a contact portion such as an arm receiving portion 8c of a valve member such as a needle valve 8. The contact portion 3a contacts the central portion of the contact portion when viewed from the rotation axis direction (X direction) of the arm member 3. When the arm member 3 rotates, the contact of the contact portion 3a with the central portion of the contact portion is maintained. According to this, as described in the embodiment, when the arm member 3 rotates, it is possible to suppress a contact portion such as the arm receiving portion 8c from inclining following the inclination of the arm member 3 due to the biasing force of the biasing member. Thereby, it is possible to suppress the needle valve 8 together with the contact portion from inclining and hitting an arm side surface such as the inner peripheral surface of the through hole 3b or hitting a regulating member such as the valve receiving portion 20. Thereby, the valve member can be displaced stably.

[0112] (Aspect 4) In Aspect 3, the contact surface of the contact portion 3a of the arm member 3 with a contact portion such as the arm receiving portion 8c is arc-shaped when viewed from the rotation axis direction (X direction) of the arm member 3. According to this, as described in the embodiment, when the arm member 3 rotates, it is possible to maintain the contact of the contact portion 3a with the central portion of the contact portion. Also, when the arm member 3 rotates, the contact location of the contact surface of the contact portion with the contact portion can be smoothly changed, and the arm member 3 can be rotated smoothly.

[0113] (Aspect 5) In any of Aspects 1 to 4, the arm side surface is the side surface of a through portion such as a through hole 3b through which a valve member such as a needle valve 8 provided in the arm member 3 penetrates. According to this, as described in the embodiment, it is possible to suppress the side surface of the through portion from hitting the valve member such as the needle valve 8 when the arm member rotates, and it is possible to suppress the movement of the valve member from being inhibited.

[0114] (Aspect 6) In Aspect 5, the through portion has a hole shape or a groove shape in which a part of the outer peripheral surface of a valve member such as the needle valve 8 is exposed. According to this, as described in the embodiment, it is possible to suppress the inner peripheral surface of the through portion having a hole shape or the side surface of the through portion having a groove shape from hitting the valve member such as the needle valve 8 when the arm member rotates, and it is possible to suppress the movement of the valve member from being inhibited.

[0115] (Aspect 7) In any one of Aspects 1 to 6, when viewed from the rotational axis direction (X direction) of the arm member 3, when the drive of the actuator 2 is in the OFF state, a line A2 connecting the connection point S between the main body 3f of the arm member 3 of the connection portion 3d and the rotation center O1 of the arm member 3 is orthogonal to the displacement direction A1 of the actuator 2. According to this, as described in the embodiment, when a voltage is applied to the actuator and the actuator is displaced, the direction in which the connection point S is pressed and the direction in which the connection point S is displaced when the arm member rotates can be made to coincide. Thereby, the arm member can be rotated satisfactorily by the displacement of the actuator.

[0116] (Aspect 8) In any one of Aspects 1 to 7, the bottom surface 3fa of the main body 3f of the arm member 3 is a flat surface. According to this, as described in the embodiment, the arm member 3 can be stably placed on the reference plane of a reference member such as a block gauge, and it is possible to suppress the arm member from tilting in the rotational direction with respect to the posture (initial posture) when the actuator is OFF during the assembly of the liquid ejection module. As a result, the gap d1 between the arm side surface and the needle valve can be accurately set to a specified gap, and it is possible to satisfactorily suppress the arm side surface from hitting the valve member when the arm member rotates. Further, when the drive of the actuator 2 is in the OFF state, a line A2 connecting the connection point S between the main body 3f of the arm member 3 of the connection portion 3d and the rotation center O1 of the arm member 3 can be accurately orthogonal to the displacement direction A1 of the actuator 2.

[0117] (Aspect 9) In any one of Aspects 1 to 8, the arm member 3 amplifies the displacement of the actuator 2 and moves a valve member such as the needle valve 8. According to this, as described in the embodiment, the movement amount of the valve member increases, and the gap between the nozzle and the valve member when the valve member is in the open position can be increased. As a result, liquid can easily flow through the nozzle, the amount of liquid ejected from the nozzle increases, and the size of the liquid droplets can be increased.

[0118] (Aspect 10) In any one of Aspects 1 to 9, there are a plurality of nozzles 14a, a valve member such as the needle valve 8, and a movement mechanism 6. According to this, droplets can be ejected from a plurality of nozzles, and productivity can be improved.

[0119] (Aspect 11) In any one of Aspects 1 to 10, a valve member such as the needle valve 8 opens and closes a plurality of nozzles 14a. According to this, as described in the modification example, the number of valve members and movement mechanisms can be reduced, and the cost of the device can be reduced. (Aspect 12) In a device 100 that ejects liquid and includes a liquid ejection head 10, as the liquid ejection head 10, a liquid ejection head according to any one of Aspects 1 to 11 is used. According to this, high-quality images can be obtained.

Explanation of Signs

[0120] 1: Liquid ejection module 2: Actuator 2a: Piezoelectric element 2b: Holder 3: Arm member 3a: Contact portion 3b: Through hole 3d: Connection portion 3d1: Adhesive surface portion 3d2: Connecting portion 3f: Main body of arm member 3fa: Bottom surface of arm member 3g: Through groove 4: Support shaft 5: Flow path 6: Moving mechanism 7: Compression spring 8: Needle valve 8a: Sealing member 8c: Arm receiving portion 10: Liquid ejection head 11: Cover 11a: Accommodating portion 11b: Valve through hole 12: Supply port 13: Discharge port 14: Nozzle plate 14a: Nozzle 14b: Through hole 14c: Positioning hole 14d: Flow path opening / closing portion 14f: Branch flow path 15: Flow path member 15a: Sealing member 15b: Female screw portion 15c: Pin fitting hole 16: Harness passing hole 17: Connection member 18: Spring receiving plate 19: Sealing member 20: Valve receiving portion 21: Fixed Holder 22: Biasing Holder 22a: Spring Portion 23: Holder 24: Biasing Receiver 25: Holder Body 26: Cover Member 27: Holder Spring 28: Actuator Lever 28a: Arm Connection Portion 28b: Element Contact Portion 28c: Connecting Side Surface Portion 30: Drive Control Device 31: Waveform Generation Circuit 32: Amplification Circuit 100: Device for Discharging Liquid O1: Rotation Center of Arm Member S: Connection Location d1: Gap between Inner Peripheral Surface of Through-Hole and Outer Peripheral Surface of Needle Valve d2: Gap between Inner Peripheral Surface of Valve Receiver and Outer Peripheral Surface of Needle Valve

Prior Art Documents

Patent Documents

[0121]

Patent Document 1

Claims

1. A nozzle for discharging a liquid, a valve member for opening and closing the nozzle, In a liquid discharge head having a moving mechanism for moving the valve member between an open position for opening the nozzle and a closed position for closing the nozzle, The moving mechanism includes an actuator, a connecting portion connected to the actuator, and an arm member that is rotatably supported and has a contact portion that contacts the valve member, A liquid discharge head, wherein an arm side surface of the arm member facing an outer peripheral surface of the valve member along a moving direction of the valve member faces the outer peripheral surface of the valve member with a predetermined gap therebetween.

2. In the liquid discharge head according to Claim 1, A restricting member for restricting movement of the valve member in a direction orthogonal to the moving direction is provided, A liquid discharge head, wherein a gap between the arm side surface and the outer peripheral surface of the valve member is wider than a gap between a restricting side surface of the restricting member facing the outer peripheral surface of the valve member and the outer peripheral surface of the valve member.

3. In the liquid discharge head according to Claim 1, A biasing member for biasing a portion of the valve member to be contacted by the contact portion of the arm member in the moving direction of the arm member toward the contact portion is provided, A liquid discharge head, wherein the contact portion contacts a central portion of the portion of the valve member to be contacted when viewed in the rotational axis direction of the arm member, and the contact of the contact portion with the central portion of the portion of the valve member to be contacted is maintained even when the arm member rotates.

4. In the liquid discharge head according to Claim 3, A liquid discharge head, wherein a contact surface between the contact portion of the arm member and the portion of the valve member to be contacted is arc-shaped when viewed in the rotational axis direction of the arm member.

5. In the liquid discharge head according to Claim 1, A liquid discharge head, wherein the arm side surface is a side surface of a through portion provided in the arm member through which the valve member passes.

6. In the liquid discharge head according to Claim 5, A liquid discharge head, wherein the through portion has a hole shape or a groove shape in which a part of the outer peripheral surface of the valve member is exposed.

7. In the liquid discharge head according to Claim 1, A liquid discharge head, wherein when viewed in the rotational axis direction of the arm member, when the drive of the actuator is in an OFF state, a line connecting a connection portion of the connecting portion to the main body of the arm member and the rotational center of the arm member is orthogonal to the displacement direction of the actuator.

8. In the liquid ejection head according to claim 1, A liquid ejection head, wherein a bottom surface of a main body of the arm member is a flat surface.

9. In the liquid ejection head according to claim 1, A liquid ejection head, wherein the arm member amplifies displacement of the actuator to move the valve member.

10. In the liquid ejection head according to claim 1, A liquid ejection head, comprising a plurality of the nozzles, the valve members, and the movement mechanisms.

11. In the liquid ejection head according to claim 1, A liquid ejection head, wherein the valve member opens and closes a plurality of nozzles.

12. In an apparatus for ejecting a liquid, comprising the liquid ejection head, An apparatus for ejecting a liquid, wherein the liquid ejection head according to claim 1 is used as the liquid ejection head.

Images