Actuator unit, liquid discharge head, and device for discharging liquid

Abstract

To provide an actuator unit, a liquid discharge head, and a device for discharging a liquid that can favorably amplify displacement of an actuator while suppressing an increase in size of the actuator unit.SOLUTION: An actuator unit includes: a piezoelectric element 18 serving as an actuator; a pair of arm members 21 that rotate in conjunction with displacement of the piezoelectric element 18; and a connecting member serving as a plate spring member 30 that connects the pair of arm members 21 and a moving member. Then, when viewed from a rotation axis direction (a X direction) of each arm member 21, the pair of arm members were disposed so as to overlap each other so that a fulcrum b of the rotation of one arm member and the fulcrum b of the rotation of the other arm member coincide with each other, or so that a line A1 connecting the fulcrum of the rotation of one arm member and a connection part of the one arm member and the plate spring member and a line A2 connecting the fulcrum b of the rotation of the other arm member and the connection part of the other arm member and the plate spring member intersect with each other.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to an actuator unit, a liquid ejection head, and a liquid ejection device. [Background technology]

[0002] 2. Description of the Related Art Conventionally, there has been known an actuator unit that includes an actuator and an amplifying mechanism that is connected to a moving member via a connecting part and that amplifies the displacement of the actuator.

[0003] Patent Document 1 describes an actuator unit having an inverse spring mechanism as an amplification mechanism. The inverse spring mechanism has a deformation portion with a generally trapezoidal cross section that is formed to abut against a valve body as a moving member. The valve body side of the deformation portion is the trapezoidal upper base, and the actuator side is the trapezoidal lower base. The valve body is connected to the upper base of this deformation portion. A guide portion that is connected to the end face of the actuator is connected to the center of the lower base of the deformation portion. Furthermore, a fixing portion that is fixed to the inner wall surface of the device main body is connected between the center of the lower base of the deformation portion and the end.

[0004] When the actuator is driven, the guide portion moves toward the nozzle and presses against the center of the lower base of the deformation portion. This causes the lower base to bend, with one side of the lower base and the other side pivoting around the connection point with the fixed portion, based on the center of the lower base of the deformation portion. This causes the peripheral edge of the deformation portion to deform and be pulled toward the actuator, and the upper base of the deformation portion, which is connected to the valve body, to move toward the actuator. As a result, the valve body is pulled toward the actuator and moves from a closed position that blocks the nozzle to an open position.

[0005] By appropriately adjusting the distance between the upper and lower bases, which are the connecting parts with the valve body in the deformation part of the reverse spring mechanism, and the length of the lower base, it is possible to make the length of movement of the valve body longer than the length of extension of the actuator. In other words, it is described that the reverse spring mechanism can amplify the slight extension of the actuator. Summary of the Invention [Problem to be solved by the invention]

[0006] However, when the amount of amplification of the displacement of the actuator by an amplification mechanism such as a reverse spring mechanism is increased, the amplification mechanism becomes larger, which poses a problem of increasing the size of the actuator unit. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems, the present invention provides an actuator unit including an actuator and an amplifying mechanism that amplifies the displacement of the actuator to move a moving member, the amplifying mechanism having a pair of arm members that rotate in conjunction with the displacement of the actuator, and a connecting member that connects the pair of arm members and the moving member, the connecting member having a first connecting member that connects the moving member to an end of one arm member in a direction perpendicular to the moving direction of the moving member with the moving member as a reference, when viewed from the direction of the rotation axis of the arm members. and a second connection portion connecting the other end of the other arm member in the orthogonal direction to the movable member, wherein, when viewed from the rotation axis direction, a pair of arm members are arranged overlapping each other so that a fulcrum of rotation of the one arm member and a fulcrum of rotation of the other arm member coincide with each other, or a line connecting the fulcrum of rotation of the one arm member and a connection portion of the one arm member with the first connection portion intersects with a line connecting the fulcrum of rotation of the other arm member and a connection portion of the other arm member with the second connection portion. [Effects of the Invention]

[0008] According to the present invention, it is possible to effectively amplify the displacement of the actuator while suppressing an increase in the size of the actuator unit. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 2 is an overall perspective view of a liquid ejection head. [Figure 2]FIG. 2 is a schematic configuration diagram showing a head unit. [Figure 3] FIG. 4 is a diagram showing an example of a driving pulse applied to a piezoelectric element. [Figure 4] FIG. 2 is a schematic diagram showing the basic configuration of a liquid ejection module. [Figure 5] FIG. 2 is a schematic configuration diagram of an actuator unit. [Figure 6] FIG. 4 is a diagram illustrating an example of the dimensional relationship between a pair of arm members. [Figure 7] FIG. 4 is an enlarged view of the vicinity of the displacement connecting portion and the fixed connecting portion of the arm member. [Figure 8] FIG. 4A is a schematic diagram of an actuator unit of a comparative example, and FIG. 4B is a schematic diagram of an actuator unit of this embodiment. [Figure 9] 10A and 10B show the analysis results. [Figure 10] FIG. 10 is a diagram illustrating a first modified example. [Figure 11] FIG. 10 is a diagram illustrating a second modified example. [Figure 12] FIG. 10 is a diagram illustrating a third modified example. [Figure 13] FIG. 10 is a diagram illustrating a fourth modified example. [Figure 14] FIG. 10 is a diagram illustrating a fifth modified example. [Figure 15] FIG. 10 is a diagram showing an example in which displacement receiving portions of a pair of arm members are integrated together. [Figure 16] FIG. 13 is a diagram illustrating a sixth modification. [Figure 17] FIG. 1 is a schematic diagram illustrating the configuration of an inkjet printer. [Figure 18] FIG. 1 is a perspective view showing an example of the arrangement of an inkjet printer in a vehicle. [Figure 19] FIG. 10 is a schematic perspective view showing another example of an inkjet printer. [Figure 20] FIG. 10 is a schematic perspective view showing yet another example of an inkjet printer. [Figure 21] FIG. 1 is a schematic perspective view showing an example of an electrode manufacturing apparatus. [Figure 22] FIG. 10 is a schematic perspective view showing another example of an electrode manufacturing apparatus. DETAILED DESCRIPTION OF THE INVENTION

[0010] The best mode for carrying out the present invention will be described below with reference to the drawings. Note that a person skilled in the art can easily modify or alter the present invention within the scope of the claims to create other embodiments, and these modifications and alterations are included within the scope of the claims. The following description is an example of the best mode for carrying out the present invention and does not limit the scope of the claims.

[0011] Fig. 1 is an overall perspective view of a liquid ejection head 10. In Fig. 1, the longitudinal direction of the liquid ejection head 10 (the direction in which the nozzles 14 are arranged) is defined as the X direction, and the lateral direction of the liquid ejection head 10 is defined as the Y direction. The height direction of the liquid ejection head 10 (the opening and closing direction of the needle valve 17, the movement direction of the needle valve 17, and the direction in which liquid is ejected from the nozzles 14) is defined as the Z direction. The definitions of these coordinates will be the same in the subsequent figures unless otherwise specified.

[0012] The liquid ejection head 10 has a housing 11 that serves as a case. The housing 11 is made of metal or resin. The housing 11 also has a connector 29 on its top for communicating electrical signals. One end of the housing 11 in the X direction has a supply port 12 for supplying liquid such as ink into the head, and the other end in the X direction has a recovery port 13 for discharging liquid from the head.

[0013] 2 is a schematic configuration diagram showing the head unit 60, and is also a cross-sectional view of the liquid ejection head 10 taken along the line AA in FIG.

[0014] The liquid ejection head 10 has a nozzle plate 15. The nozzle plate 15 is joined to the housing 11. The nozzle plate 15 has a plurality of nozzles 14 for ejecting liquid arranged in the longitudinal direction (X direction) of the liquid ejection head 10. The housing 11 is provided with a flow path 16 through which the liquid flows. The flow path 16 is a path through which the liquid supplied from the supply port 12 passes over the nozzle plate 15 and is sent to the recovery port 13. The liquid is sent on the flow path 16 in the directions indicated by arrows a1 to a3 in FIG. 2.

[0015] With the above configuration, supply port 12 takes in pressurized liquid from the outside, sends the liquid in the direction of arrow a1, and supplies the liquid to flow path 16. Flow path 16 sends the liquid from supply port 12 in the direction of arrow a2. Then, recovery port 13 discharges the liquid that has not been ejected from nozzles 14 arranged along flow path 16 in the direction of arrow a3.

[0016] A plurality of liquid ejection modules 70 are arranged between the supply port 12 and the recovery port 13. The number of liquid ejection modules 70 corresponds to the number of nozzles 14, and in this example, a configuration is shown in which eight liquid ejection modules 70 corresponding to the eight nozzles 14 arranged in a row are provided. Note that the number and arrangement of the nozzles 14 and liquid ejection modules 70 are not limited to those described above. For example, the number of nozzles 14 and liquid ejection modules 70 may be one instead of multiple. The number may also be eight or more or less. The nozzles 14 and liquid ejection modules 70 may also be arranged in multiple rows instead of a single row.

[0017] Each liquid ejection module 70 includes a needle valve 17 as a valve member that opens and closes the nozzle 14, and a piezoelectric element 18 as an actuator that drives the needle valve 17. By displacing the piezoelectric element 18, the needle valve 17 is opened and closed, and liquid is ejected from the nozzle 14.

[0018] The housing 11 is provided with a plurality of storage sections 11a (see FIG. 4) that each store a liquid ejection module 70. Each storage section 11a is provided with a piezoelectric element regulating member 19 at a position facing the upper end of the piezoelectric element 18 that serves as an actuator. The piezoelectric element regulating member 19 abuts against the upper end of the piezoelectric element 18, and serves as a fixing point for the piezoelectric element 18.

[0019] A through-hole through which the needle valve 17 passes is formed between the storage section 11a and the flow path 16, and an O-ring 22 (see Figure 4) is provided inside the through-hole to seal the gap between the through-hole and the needle valve 17.

[0020] A sealing member, which is an elastic member, is provided at the tip of the needle valve 17. When the sealing member of the needle valve 17 is pressed against the nozzle plate 15, the sealing member is compressed, thereby reliably closing the nozzle 14 with the needle valve 17.

[0021] When a voltage is applied to the piezoelectric element 18 by the drive control device 40, the piezoelectric element 18 is displaced in the Z direction, and the needle valve 17 is pulled up in a direction away from the nozzle 14 by the actuator unit 58, which will be described later. This causes the needle valve 17 to move away from the nozzle 14 and open the nozzle 14. This causes the liquid supplied under pressure to the flow path 16 to be ejected from the nozzle 14. Furthermore, when no voltage is applied to the piezoelectric element 18, the needle valve 17 closes the nozzle 14. In this state, even if liquid is supplied under pressure to the flow path 16, the liquid will not be ejected from the nozzle 14.

[0022] The drive control device 40 has a waveform generation circuit 41, which is a drive pulse generation unit, and an amplifier circuit. The waveform generation circuit generates a drive pulse waveform, which will be described later, and the amplifier circuit amplifies the voltage value to the required value. The amplified voltage is then applied to the piezoelectric element 18. By applying this voltage, the drive control device 40 controls the opening and closing of the needle valve 17, thereby controlling the ejection of liquid from the liquid ejection head 10. However, if the waveform generation circuit can apply a sufficient voltage, the amplifier circuit may be omitted.

[0023] FIG. 3 is a diagram illustrating an example of a driving pulse. The waveform generating circuit 41 generates a drive pulse as shown in Figure 3, which is a waveform that changes over time as the voltage applied to the piezoelectric element 18 changes. The waveform generating circuit receives print data from an external PC or an internal microcomputer of the device and generates a drive pulse based on this input data. The waveform generating circuit can change the voltage applied to the piezoelectric element 18 and generate multiple drive pulses. As described above, when the waveform generating circuit generates a drive pulse, the piezoelectric element 18 expands and contracts in accordance with the drive pulse, opening and closing the needle valve 17.

[0024] FIG. 4 is a schematic diagram showing the basic configuration of the liquid ejection module 70. As shown in FIG. FIG. 4(a) is a schematic diagram showing the state in which the needle valve 17 closes the nozzle 14, and FIG. 4(b) is a schematic diagram showing the state in which the needle valve 17 opens the nozzle 14. The liquid ejection module 70 is accommodated in the accommodation portion 11a of the housing 11, and includes a needle valve 17, which is a movable member and valve member that opens and closes the nozzle 14, and an actuator unit 58. The actuator unit 58 has a piezoelectric element 18 as an actuator, a pair of arm members 21 as an amplification mechanism, and a leaf spring member 30 as a connecting part.

[0025] The pair of arm members 21 have an arm portion 21a, a fixed portion 21b, a displacement receiving portion 21c, a fixed connecting portion 21d, and a displacement connecting portion 21e. A fitting hole is formed in the center of the fixed portion 21b, and the fixed portion 21b is fitted and fixed to a fixed shaft 64 provided on a holder 63. The displacement receiving portion 21c is fixed to the piezoelectric element 18 with an adhesive or the like and receives the displacement of the piezoelectric element 18.

[0026] Fixed connecting portion 21d extends in the Z direction and connects fixed portion 21b and arm portion 21a. Displacement connecting portion 21e extends in the Z direction and connects displacement receiving portion 21c and arm portion 21a. Arm member 21 is made of stainless steel, and fixed connecting portion 21d and displacement connecting portion 21e are like leaf springs and are elastically deformable. Note that fixed connecting portion 21d and displacement connecting portion 21e may be made of other metals as long as they are elastically deformable, and the arm member may be made of an elastic material such as rubber or resin.

[0027] The leaf spring member 30 serving as a connecting member is formed by bending a stainless steel sheet metal to form a valve connection portion 31 connected to the needle valve 17, a pair of inclined portions 32 serving as elastic deformation portions, and a pair of arm connection portions 33. The needle valve 17 is joined to the valve connection portion 31 with an adhesive, and the inclined portions 32 serving as elastic deformation portions extend diagonally upward in the figure from both ends of the valve connection portion 31. The arm connection portions 33 are fitted into slits provided at the outer ends of the arm portions 21a of the arm member 21 in the Y direction, and are attached to the arm portions 21a.

[0028] As shown in FIG. 4(a), when the needle valve 17 closes the nozzle 14 (when the needle valve 17 is in the closed position), the pair of inclined portions 32 of the leaf spring member 30 elastically deform as shown by the dashed lines in the figure, generating a biasing force that presses the needle valve 17 against the nozzle plate 15.

[0029] As shown in FIG. 4(b), the piezoelectric element 18 is displaced toward the nozzle 14, thereby pressing against the displacement receiving portions 21c of the pair of arm members 21. As a result, the fixed connecting portions 21d and the displacement connecting portions 21e of the pair of arm members 21 are elastically deformed so as to bend, and the arm portions 21a rotate around the vicinity of the fixed portion 21b as a fulcrum. As the arm portions 21a rotate, both ends of the leaf spring member 30 move in directions away from each other. This lifts the needle valve 17, opening the nozzle 14 and causing liquid to be ejected from the nozzle 14 (this corresponds to a state in which the needle valve 17 is in the open position that opens the nozzle 14).

[0030] Next, the actuator unit 58, which is a feature of this embodiment, will be described in detail. FIG. 5 is a schematic diagram of the actuator unit 58. As shown in FIG. In this embodiment, as shown in FIG. 5(b), the pair of arm members 21 are arranged with a shift in the rotation axis direction (X direction), and the pair of arm members 21 are arranged so that a portion of the arm portion overlaps when viewed from the rotation axis direction (X direction).

[0031] In this embodiment, the arm member 21 amplifies the displacement of the piezoelectric element 18 using the principle of leverage to move the needle valve 17. The position in the Y direction of the connection point between the arm portion 21a and the displacement connection portion 21e is the force point a in the principle of leverage.

[0032] The point of connection between arm portion 21a and fixed connecting portion 21d serves as fulcrum b in the principle of leverage. The position in the Y direction of slit portion 21f of arm portion 21a, into which leaf spring member 30 is fitted, serves as point of action c in the principle of leverage.

[0033] 4(b), when the piezoelectric element 18 is displaced, the fixed connecting portion 21d is elastically deformed so as to bend, and the connection point of the arm portion 21a with the fixed connecting portion 21d, which is the fulcrum b of the arm portion 21a, is displaced. Therefore, the arm portion does not move in a perfect circle around the connection point of the arm portion 21a with the fixed connecting portion 21d as a fulcrum, but rather moves in a pseudo-rotation. However, in this pseudo-rotation, the connection point of the arm portion 21a with the fixed connecting portion 21d is displaced the least, and can be regarded as the fulcrum b in the principle of leverage.

[0034] The distance L1 from the force point a (the Y-direction position of the connection point between the arm portion 21a and the displacement connection portion 21e) to the fulcrum b (the Y-direction position of the connection point between the arm portion and the fixed connection portion 21d) is set shorter than the distance L2 from the fulcrum b to the action point c (the Y-direction position of the slit portion 21f). This makes it possible to amplify the displacement of the piezoelectric element 18. The amount of displacement amplification by the arm member can be expressed as (L2 / L1).

[0035] By amplifying the displacement of the piezoelectric element 18, the movement of the needle valve 17 increases, and the gap between the nozzle 14 and the needle valve 17 can be increased when the needle valve 17 is in the open position. As a result, the liquid flows more easily into the nozzle 14, the amount of liquid ejected from the nozzle 14 increases, and the size of the droplets can be increased.

[0036] The longer L2 is relative to L1, the greater the amount of amplification of the displacement of the piezoelectric element 18. Therefore, by increasing the length of the arm portion 21a in the Y direction, it becomes possible to increase L2 relative to L1, thereby increasing the amount of amplification of the displacement of the piezoelectric element 18. However, increasing the length of the arm portion 21a in the Y direction increases the size of the actuator unit 58 in the Y direction.

[0037] In this embodiment, the pair of arm members 21 are arranged so that the arm portions 21a partially overlap. Specifically, the pair of arm members 21 are overlapped so that a line A1 connecting the fulcrum b of one arm member to the slit portion 21f, which is the connection portion with the leaf spring member 30, intersects with a line A2 connecting the fulcrum b of the other arm member to the slit portion 21f. This makes it possible to increase the amount of amplification of the displacement of the piezoelectric element 18 while suppressing an increase in the size of the actuator unit 58 in the Y direction, compared to a non-overlapping configuration.

[0038] FIG. 6 is a diagram illustrating an example of the dimensional relationship between the pair of arm members 21. In FIG. As shown in Fig. 6, in this embodiment, the distance Aw from the outer end of one arm member in the Y direction to the outer end of the other arm member in the Y direction is 4 to 10 mm. The height (length in the Z direction) Ah of the arm portion of each arm member is 4 to 15 mm. The width (length in the Y direction) Sw of the leaf spring member 30 is 3.5 to 9.5 mm, and the length Sh from the bottom end of the arm member to the bottom end of the leaf spring member is 3.5 to 9.5 mm. The pair of arm members are preferably arranged so that the overlap width Pw between the pair of arm members is 60% or more of the above-mentioned Aw. The dimensions shown in FIG. 6 are merely an example, and may be appropriately designed depending on the required amount of displacement, resonance frequency characteristics, size of the piezoelectric element, etc.

[0039] FIG. 7 is an enlarged view of the vicinity of the displacement connecting portion 21e and the fixed connecting portion 21d of the arm member 21. As shown in FIG. In this embodiment, the arm member 21 is made of metal such as stainless steel. Therefore, the ratio (Bw / Bt) of the width (length in the Y direction) Bw to the thickness Bt of the fixed connecting portion 21d and the ratio (Cw / Ct) of the width (length in the Y direction) Cw to the thickness of the displacement connecting portion 21e are appropriately set to allow elastic deformation when the piezoelectric element 18 is displaced. Because the fixed portion 21b is fixed, the fixed connecting portion 21d elastically deforms when the arm portion 21a rotates, thereby suppressing stress concentration at the connection points of the fixed connecting portion 21d with the arm portion 21a and with the fixed portion 21b.

[0040] Displacement receiving portion 21c of arm member 21 is also fixed to piezoelectric element 18 with adhesive or the like so as to ensure good transmission of displacement from piezoelectric element 18. Therefore, when arm portion 21a rotates, displacement connecting portion 21e elastically deforms, thereby suppressing stress concentration at the connection point of displacement connecting portion 21e with arm portion 21a and the connection point with displacement receiving portion 21c.

[0041] However, if the values ​​of (Bw / Bt) and (Cw / Ct) are reduced to facilitate elastic deformation, the responsiveness of the needle valve 17 may decrease, preventing high-frequency driving. Furthermore, the elastic deformation of the displacement connecting portion 21e may absorb the displacement of the piezoelectric element 18, reducing the amount of rotation of the arm portion 21a and the amount of movement of the needle valve 17. Furthermore, if the fixed connecting portion 21d becomes more susceptible to elastic deformation, the function of the arm portion 21a as the fulcrum b of the lever may decrease, reducing the amount of deformation at the point of application c.

[0042] In this embodiment, in order to minimize elastic deformation of fixed connecting portion 21d and prevent damage to the arm member due to stress concentrated at the connecting point of fixed connecting portion 21d, the width Bw and thickness Bt of fixed connecting portion 21d are set as follows: That is, the ratio (Bw / Bt) of the width Bw to the thickness Bt of fixed connecting portion 21d is set to be 0.05 or more and 1.5 or less.

[0043] As for the displacement connecting portion 21e, in order to minimize elastic deformation and keep the stress concentrated at the connecting portion of the displacement connecting portion 21e below the yield point, the width Cw and thickness Ct of the displacement connecting portion 21e are set as follows: That is, the ratio of the width Cw to the thickness Ct of the displacement connecting portion 21e (Cw / Ct) is set to 0.05 or more and 1.5 or less.

[0044] This minimizes elastic deformation of the fixed connecting portion 21d and the displacement connecting portion 21e, while preventing damage to the arm member due to stress concentrated at the connecting points of the connecting portions 21d, 21e. This prevents a decrease in durability of the arm member 21. Furthermore, the elastic deformation of the fixed connecting portion 21d and the displacement connecting portion 21e is moderate, preventing a decrease in responsiveness and enabling high-frequency driving. It also prevents a decrease in the amount of movement of the needle valve 17. Furthermore, by setting the ratio (Bw / Bt) of the width Bw to the thickness Bt of the fixed connecting portion 21d to be 0.05 or more to prevent elastic deformation, it is possible to prevent a decrease in the function of the arm portion as the fulcrum b of the lever and prevent a decrease in the amount of deformation at the point of application c.

[0045] It is also preferable to set the above (Bw / bt) and (Cw / Ct) so that the stress applied to the connection points of each of the connecting portions 21d, 21e is 50% or more of the yield point but less than the yield point, thereby suppressing plastic deformation of the arm member 21 due to the stress applied to the connection points of each of the connecting portions 21d, 21e while minimizing elastic deformation of each of the connecting portions 21d, 21e.

[0046] Next, a test for confirming the effect of this embodiment will be described. FIG. 8(a) is a schematic diagram of the actuator unit of a comparative example, and FIG. 8(b) is a schematic diagram of the actuator unit of this embodiment. As shown in FIG. 8(a), the actuator unit of the comparative example has a configuration in which the pair of arm members do not overlap.

[0047] The distance Aw from the outer end of one arm member in the Y direction to the outer end of the other arm member in the Y direction, the height Ah of the arm member, the width Sw of the leaf spring member, and the height Sh of the leaf spring member shown in Fig. 8 are the same in the comparative example and this embodiment. That is, in this embodiment shown in Fig. 8(b), the pair of arm members are overlapped so that the distance Aw is the same as in the comparative example.

[0048] Furthermore, the width Bw of the fixed connecting portion 21d and the width Cw of the displacement connecting portion 21e are adjusted so that the stress applied to each connecting point of the fixed connecting portion 21d and each connecting point of the displacement connecting portion 21e is the same in the comparative example and this embodiment. Note that the thickness Bt of the fixed connecting portion 21d and the thickness Ct of the displacement connecting portion 21e are the same in the comparative example and this embodiment.

[0049] For the comparative example and the present embodiment, two pairs of arm members were prepared, each with a different ratio (L2 / L1) between the distance L1 from the force point a of the arm portion 21a (the connection point of the arm portion 21a with the displacement connection portion 21e) to the fulcrum b of the arm portion 21a (the connection point of the arm portion 21a with the fixed connection portion 21d) and the distance L2 from the fulcrum b of the arm portion 21a to the action point c of the arm portion 21a (the Y-direction position of the slit portion 21f). For the comparative example, the ratios were c and d (c > d), while for the present embodiment, the ratios were c1 (≒ c) and d1 (c1 > d1). Furthermore, the ratio (Bw / Bt) of the width Bw to the thickness Bt of the fixed connection portion 21d in the comparative example when the ratio was c was 0.2, while in the present embodiment, the ratio (Bw / Bt) when the ratio was c1 (≒ c) was 0.4.

[0050] In the effectiveness confirmation test, the amount of output displacement and the resonance frequency were examined when the force point a of the arm portion (the connection point of the arm portion 21a with the displacement connection portion) was displaced downward by 20 μm. The output displacement amount was analyzed by using analysis software (Ansys Mechanical, manufactured by ANSYS, Inc.) to measure the displacement amount of the valve connection portion 31 of the leaf spring member 30. The resonance frequency was also analyzed using the same analysis software.

[0051] Note that when measuring the output displacement and resonance frequency of an actual device, they can be measured using a laser Doppler vibrometer (LDV). The output displacement can be obtained by measuring the vibration of the valve connection portion 31 of the leaf spring member 30 in the Z direction using the laser Doppler vibrometer (LDV) and integrating the velocity transient response data measured by the laser Doppler vibrometer (LDV). The resonance frequency can be obtained by Fourier transforming the velocity transient response data measured by the laser Doppler vibrometer (LDV) in the free vibration state of the valve connection portion 31 of the leaf spring member 30 in the Z direction.

[0052] FIG. 9 is a diagram showing the analysis results. As shown in Figure 9, as the ratio increases, the resonant frequency decreases and the rigidity of the arm member weakens. This is because, although increasing the ratio increases the output displacement, as the ratio increases, the force required to lift the valve connection portion of the leaf spring member also increases. As a result, the stress applied to each connection point of the fixed connection portion 21d and each connection point of the displacement connection portion 21e also increases. Therefore, in order to maintain the stress applied to each connection point at a predetermined value, it is necessary to reduce the width-to-thickness ratios (Bw / Bt) and (Cw / cCt) of the fixed connection portion 21d and the displacement connection portion to facilitate elastic deformation. As a result, as the ratio increases, the resonant frequency of the arm member decreases.

[0053] Furthermore, as shown in FIG. 9 , when comparing the comparative example and this embodiment, the present embodiment can increase the rigidity of the arm member and therefore the resonant frequency. As described above, the ratio (Bw / Bt) of the width Bw to the thickness Bt of the fixed connecting portion 21d in the comparative example when the ratio is c is 0.2. However, in the present embodiment, when the ratio is c1 (≈c), the ratio (Bw / Bt) is 0.4, which increases the rigidity of the fixed connecting portion 21d. This is because, in this embodiment, the pair of arm members overlap, which increases the distance from the point of application c to the fulcrum b compared to the comparative example. This reduces the stress applied to the fulcrum b (the connection point between the fixed connecting portion 21d and the arm portion 21a) when the same amount of displacement is generated at the point of application c compared to the comparative example. In the effectiveness confirmation test, as described above, the width Bw of the fixed connecting portion 21d and the width Cw of the displacement connecting portion 21e were adjusted so that the stress applied to each connecting point of the fixed connecting portion 21d and each connecting point of the displacement connecting portion 21e was the same in the comparative example and the present embodiment. Therefore, in the present embodiment, in which the stress applied to the fulcrum portion b (the connecting point between the fixed connecting portion 21d and the arm portion 21a) is smaller than in the comparative example, (Bw / Bt) can be made larger than in the comparative example, and the rigidity of the fixed connecting portion 21d can be increased.

[0054] In this way, in this embodiment, by overlapping a pair of arm members, the output displacement amount can be increased without increasing the size of the device in the Y direction, and the rigidity of the arm members can be increased to improve responsiveness.

[0055] Next, a modified example of the actuator unit will be described.

[0056] [Variation 1] FIG. 10 is a diagram illustrating the first modification. 10, in Modification 1, a pair of arm members 21 are overlapped so that a line A1 connecting from the displacement receiving portion 21c of one arm member to the slit portion 21f, which is the connection portion with the leaf spring member 30, intersects with a line A2 connecting from the displacement receiving portion 21c of the other arm member to the slit portion 21f. Note that the displacement receiving portions 21c of each arm member 21 may be provided at the same position in the Y direction.

[0057] In the arrangement of the pair of arm members 21 of this embodiment shown in FIG. 5, the displacement receiving portion 21c of one arm member 21 and the displacement receiving portion 21c of the other arm member 21 are spaced apart in the Y direction. As a result, the piezoelectric element 18 is larger in the Y direction. On the other hand, in Modification 1 shown in FIG. 10, the displacement receiving portion 21c of one arm member 21 and the displacement receiving portion 21c of the other arm member 21 are closer in the Y direction, which makes it possible to reduce the size of the piezoelectric element 18. On the other hand, in the embodiment shown in FIG. 5, the overlap width Pw of the pair of arm members 21 can be made wider, which makes it possible to lengthen the arm members 21 in the Y direction, and this has the advantage of being able to effectively amplify the displacement of the actuator.

[0058] [Variation 2] FIG. 11 is a diagram illustrating the second modification. As shown in FIG. 11, in the second modification, the arm member 21 is provided with a displacement receiving portion 21c (displacement connecting portion 21e) between the fixed portion 21b (fixed connecting portion 21d) and the slit portion 21f in the Y direction. 11(a) shows a pair of arm members 21 arranged in the Y direction so that the displacement receiving portion 21c (displacement connecting portion 21e) is located between the fixed portions 21b of each arm member 21. FIG. 11(b) shows an arrangement in which the displacement connecting portion 21e of one arm member 21 overlaps the fixed portion 21b of the other arm member 21. In the configuration shown in FIG. 11(b), the fixed portion 21b of one arm member 21 is fixed to the device from the -X direction, and the fixed portion 21b of the other arm member 21 is fixed to the device from the +X direction.

[0059] In the configuration shown in Figure 11, by compressing the piezoelectric element 18 and pulling up the displacement receiving portion 21c of each arm member 21, the arm portion 21a of each arm member 21 is rotated so that both ends of the leaf spring member 30 move in directions away from each other.

[0060] [Variation 3] FIG. 12 is a diagram illustrating the third modification. In the third modification shown in FIG. 12, the fixing portions 21b of the arm members 21 are overlapped with each other. As shown in Figure 12(a), the fixed portion 21b of each arm member 21 has two fitting holes 21b1 arranged side by side in the Y direction, and a fixed shaft 64 (see Figure 4) fits into these fitting holes 21b1 to fix the fixed portion 21b of each arm member 21. In Figure 12(b), one fitting hole 21b1 is provided in the fixed portion 21b of each arm member 21, and one fixed shaft 64 fixes the fixed portion 21b of each arm member 21.

[0061] 12(a), the distance between the fixed axes can be narrowed compared to when the fixed portions 21b are not overlapped, and the device can be made more compact. Furthermore, the configuration shown in FIG. 12(b) is more preferable because it reduces the number of parts and reduces the cost of the device.

[0062] [Variation 4] FIG. 13 is a diagram illustrating the fourth modification. As shown in FIG. 13, in the fourth modification, the arm portion 21a of each arm member 21 is provided with a thick portion 21g. The thick portion 21g is provided in a portion of the arm portion 21a around the slit portion 21f into which the arm connecting portion 33 of the leaf spring member 30 is fitted, where the thick portion 21g does not overlap with the other arm member when the arm member rotates. This increases the rigidity around the slit portion 21f and suppresses deformation around the slit portion 21f of the arm member 21. This suppresses twisting of the leaf spring member 30 around the Z direction, stabilizing the opening and closing movement of the needle valve 17.

[0063] 13, only the periphery of the slit portion 21f of the arm portion 21a is thickened, but other portions of the arm portion 21a that do not overlap with the other arm member 21 when the arm member 21 rotates may also be thickened to increase the rigidity of the arm portion 21a. This can further suppress deformation of the arm portion 21a and suppress twisting of the leaf spring member 30 around the Z direction. Furthermore, the thick portion 21g may be provided on only one of the pair of arm members 21.

[0064] [Variation 5] 14A and 14B are diagrams illustrating Modification 5. Fig. 14A is an enlarged front view of a main part of the actuator unit of Modification 5, and Fig. 14B is a side view of the actuator unit of Modification 5. As shown in FIG. 14, in variant 5, a transmission member 65 is disposed between the piezoelectric element 18 and the arm member 21, so that the displacement of the piezoelectric element 18 is transmitted to the arm member 21 via the transmission member 65.

[0065] The transmission member 65 needs to transmit the displacement of the piezoelectric element 18 evenly to each arm member 21. For this reason, the contact surface between the lower surface of the piezoelectric element 18 and the transmission member 65 is perpendicular to the Z direction, and the contact surface is fixed to the lower surface of the piezoelectric element 18 so that the center of the contact surface of the transmission member coincides with the center of the lower surface of the piezoelectric element 18. Stainless steel is suitable as the material for the transmission member 65. However, the transmission member 65 may be made of other metals, resins, or the like, as long as it is strong enough not to deform when the piezoelectric element 18 is displaced.

[0066] 14, for ease of assembly, the displacement receiving portion 21c of each arm member 21 is joined to the respective side surface of the transmission member 65 that is perpendicular to the X direction. The displacement receiving portion 21c of each arm member 21 may also be joined to the side surface of the transmission member 65 that is perpendicular to the X direction. However, to ensure sufficient joint strength with the transmission member 65, it is preferable to join the displacement receiving portion 21c of each arm member 21 to the side surface of the transmission member 65 that is perpendicular to the X direction and has a large surface area.

[0067] Furthermore, in order to ensure sufficient joint strength between displacement receiving portion 21c and transmission member 65, it is preferable to shape transmission member 65 so that the side surface perpendicular to the X direction has as large an area as possible. Furthermore, a configuration may be provided in which displacement receiving portion 21c of each arm member 21 is provided with a positioning pin, and transmission member 65 is provided with a positioning hole, thereby positioning displacement receiving portion 21c to transmission member 65.

[0068] By providing a transmission member 65 as shown in Modification 4, the displacement transmitted to each arm member 21 can be made uniform compared to when the displacement receiving portion 21c of each arm member 21 is directly joined to the underside of the piezoelectric element. This makes it possible to prevent differences in the amount of output displacement of each arm member 21, and allows the needle valve 17 to move stably and straight in the Z direction.

[0069] 15, the displacement receiving portions 21c of the arm members 21 may be integrally configured. Even with this configuration, the displacement of the piezoelectric element 18 can be uniformly transmitted to the arm portions 21a of the arm members 21, preventing differences in the amount of output displacement of the arm members 21, and allowing the needle valve 17 to stably move straight in the Z direction.

[0070] [Variation 6] FIG. 16 is a diagram illustrating the sixth modification. FIG. 16(a) is a schematic front view of the actuator unit of the sixth modification, and FIG. 16(b) is a schematic front view of the actuator unit of the sixth modification with the front restricting member 67a removed. In the sixth modification, the holder 63 that holds the piezoelectric element 18 and the fixing portions 21b of each arm member 21 are positioned and fixed by a pair of regulating members 67a, 67b that regulate the position of the piezoelectric element 18 in the Z direction via the holder 63. The holder 63 is provided with a piezoelectric element fixing portion 63b to which the upper end of the piezoelectric element 18 is fixed, and two restriction holes 63a into which the restriction shaft 68 fits. Stainless steel is suitable as the material for the holder 63, but other metals or resins may also be used as long as they are strong enough not to deform when the actuator unit is driven.

[0071] Two restriction shafts 68 are provided on the upper part of one restriction member 67a of the pair of restriction members 67a, 67b, and two fixed shafts 64 are provided below this one restriction member 67a, which respectively fit into fitting holes 21b1 of the fixed portion 21b of each arm member 21. The other restriction member 67b is provided with two restriction holes that overlap with the two restriction holes 63a of the holder 63, and holding holes that overlap with the fitting holes 21b1 provided in the fixed portion 21b of the arm member 21 and hold the fixed shafts 64. The fixed shafts 64 and restriction shafts 68 may be provided on the restriction members by integral molding.

[0072] The material of each of the restricting members 67a, 67b is preferably a metal with a low coefficient of thermal expansion, such as Invar (for example, an alloy of Fe and Ni, whose linear expansion coefficient is 0 in a specific temperature range), which can suppress changes in overall length due to temperature rise when the piezoelectric element 18 is driven. Note that the material of each of the restricting members 67a, 67b is not limited to the above, and any material with a low coefficient of thermal expansion that does not deform due to displacement of the piezoelectric element 18 and has a low coefficient of thermal expansion may be used, such as resin.

[0073] By fitting the two regulating shafts 68 of one regulating member 67a into the regulating holes 63a of the holder 63 and the regulating holes of the other regulating member 67b, the piezoelectric element 18 held by the holder 63 is positioned in the Z direction by the regulating members.

[0074] In addition, each fixed shaft 64 provided on one regulating member 67a is fitted into the fitting hole 21b1 of the fixed portion 21b of each arm member 21, and the tip of the fixed shaft 64 is fitted into the retaining hole of the other regulating member 67b, thereby fixing each arm member 21 by the pair of regulating members.

[0075] In this sixth modification, the fixed portion 21b of each arm member 21 is fixed to regulating members 67a and 67b that regulate the Z-direction position of the piezoelectric element 18. This reduces the need for assembly precision and component precision, compared to when the fixed portion 21b of each arm member 21 is fixed to a fixed shaft held in the housing of the liquid ejection head, and makes it possible to improve the positional precision between the piezoelectric element 18 and each arm member 21.

[0076] In the above description, the pair of regulating members 67a, b sandwich the holder 63 and each arm member 21 in the X direction to regulate the positional relationship between the piezoelectric element 18 and each arm member 21, but a single regulating member may be used. However, using a pair of regulating members is preferable because it supports the regulating shaft 68 and the fixed shaft 64 at both ends and prevents the regulating shaft 68 and the fixed shaft 64 from tilting.

[0077] In the above description, the piezoelectric element 18 is used as the actuator, but the actuator may be another electrically driven device such as a pneumatically driven piston equipped with a solenoid or electromagnetic valve. Furthermore, the needle valve 17 may be opened and closed by air pressure or hydraulic pressure. In this case, the drive pulse generated by the drive control device 40 is a drive waveform for driving the pneumatic or hydraulic pressure pressurizing mechanism at a set pressure.

[0078] The liquid ejection head 10 described above is a valve jet type, and can eject highly viscous liquids and large droplets (diameters of tens to hundreds of μm) toward a target object located at a distance (tens of mm away). Furthermore, the nozzle diameter can be increased, and liquids containing large particle diameter materials can also be ejected effectively. Because the liquid ejection head 10 can eject highly viscous liquids, it is suitable for painting car and truck bodies, aircraft fuselages, building walls, road surfaces, and the like, as well as for printing images. It can also be used favorably for forming electrodes for lithium-ion batteries and the like installed in vehicle bodies.

[0079] An example of a liquid ejection device having the above-described liquid ejection head 10 will now be described.

[0080] FIG. 17 is a schematic diagram of an inkjet printer 810 as a device for discharging liquid, and FIG. 18 is a perspective view showing an example of the placement of the inkjet printer 810 relative to an automobile U1. 17, an inkjet printer 810 includes a liquid ejection unit 100 having a liquid ejection head, and a camera 812 serving as an image capturing means disposed near the liquid ejection unit 100. The inkjet printer 810 also includes an XY table 811 serving as a scanning movement mechanism that moves the liquid ejection unit 100 and the camera 812 in the X and Y directions.

[0081] The inkjet printer 810 also includes a control unit 600. The control unit 600 operates the XY table 811 based on image editing software S that edits images captured by the camera 812 and a preset control program to eject ink from the liquid ejection unit 100 and control printing on a surface to be printed. The inkjet printer 810 also includes a drive unit 620 that positions the camera 812 and the liquid ejection unit 100 at predetermined positions based on control from the control unit 600 and performs operations of capturing images and printing.

[0082] The liquid ejection unit 100 is equipped with multiple liquid ejection heads that eject ink toward the surface of an automobile U1 (see FIG. 18) that serves as the object to be coated. Note that "ink" here also includes "paint." The nozzle surfaces of the liquid ejection heads are parallel to the XY plane formed by the movement of the XY table 811, and ink dots ejected from each nozzle are ejected in the Z direction, which is perpendicular to the XY plane.

[0083] The liquid ejection unit 100 has a plurality of liquid ejection heads, each connected to an ink tank of a predetermined color, which is pressurized by a pressure device. Ink from the ink tank is supplied from a supply port 12 (see FIG. 1) of the liquid ejection head and discharged from a recovery port 13 (see FIG. 1) of the liquid ejection head. The ink discharged from the recovery port 13 is recovered into the ink tank.

[0084] If the distance between the nozzle surface of the liquid ejection head and the print surface of the car U1 is about 20 cm, ink dots can be ejected onto the print surface of the car U1 without any problems.

[0085] The XY table 811 is provided with a Y-axis rail 813 formed with a linear movement mechanism, and an X-axis movement mechanism 814 that moves the Y-axis rail 813 in the X direction while holding the Y-axis rail 813 with two arms.

[0086] The liquid discharge unit 100 and a camera 812, which will be described later, are attached to a slider held by a Y-axis rail 813. A shaft 815 is provided on the X-axis movement mechanism 814, and this shaft 815 is held by a robot arm 816. This robot arm allows the liquid discharge unit 100 to be freely positioned at a predetermined position on the automobile U1 where printing is to be performed.

[0087] For example, the robot arm 816 can be placed above the vehicle U1 as shown in Fig. 18(a) or to the side of the vehicle U1 as shown in Fig. 18(b). The operation of the robot arm 816 is controlled based on a program stored in advance in the control unit 600.

[0088] The camera 812 is mounted on a slider on a Y-axis rail 813 near the liquid discharge unit 100 and moves in the X and Y directions while capturing images of a predetermined range of the surface to be printed on the automobile U1 at constant, minute intervals. The camera 812 is a so-called digital camera, and as described above, the specifications of the lens, resolution, etc. that enable capturing multiple sub-divided images of the predetermined range of the surface to be printed are appropriately selected. The capturing of the multiple sub-divided images of the surface to be printed by the camera 812 is performed continuously and automatically according to a program pre-installed in the control unit 600.

[0089] The control unit 600 includes a storage device that records and saves various programs, data on captured images and data on images to be printed, and a central processing unit that executes various processes in accordance with the programs. The control unit 600 is also configured as a so-called microcomputer that includes input devices such as a keyboard and a mouse, and a DVD player, etc., if necessary.

[0090] In addition, the inkjet printer 810 further includes a monitor 610, which displays information input to the control unit 600, the results of processing by the control unit 600, and the like. As will be described later, the control unit 600 uses image processing software to process the multiple pieces of subdivided image data captured by the camera 812, and generates a composite print surface by projecting the non-flat print surface of the automobile U1 onto a flat surface. The control unit 600 also edits the image to be drawn as follows to generate the edited image to be drawn. That is, the image to be drawn, which is an image to be printed so as to be continuous with the image already printed on the print surface, is superimposed on the composite print surface, and the image to be drawn is edited so as to be continuous with the edge of the already printed image.

[0091] For example, an edited image to be drawn is generated by editing (deforming) the image to be drawn so that it fits into the composite print surface so that no non-print area is formed between adjacent images to be drawn. Then, based on this edited image to be drawn, printing is actually performed by the liquid ejection unit 100. This makes it possible to print a print image with no gaps between already printed print images. Note that the photographing of multiple subdivided images by the camera 812 and the printing by ejecting ink from the nozzles of each liquid ejection head of the liquid ejection unit 100 are performed by the drive unit 620, whose operation is controlled by the control unit 600.

[0092] FIG. 19 is a schematic perspective view showing another example of an inkjet printer as a device for ejecting liquid. Another example of an inkjet printer 830 includes a movable frame unit 840 that is installed facing an object U2 to be ejected. The frame unit 840 includes a Y-axis rail 833 extending horizontally, a plurality of X-axis rails 834 extending vertically and provided at predetermined intervals, and a Z-axis rail 835 intersecting the X-axis rail 834 and the Y-axis rail 833.

[0093] Each X-axis rail 834 holds a Y-axis rail 833 extending horizontally so that the Y-axis rail 833 can move in the X direction (the direction in which the nozzles of the liquid ejection head are arranged, which is the vertical direction). Furthermore, the Y-axis rail 833 holds a Z-axis rail 835 so that the Z-axis rail 835 can move in the Y direction. Furthermore, the Z-axis rail 835 holds the carriage 831 so that the carriage 831 can move in the Z direction.

[0094] The carriage 831 is equipped with a head holder 832. The head holder 832 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. It may also hold a W-color liquid ejection head that ejects white paint. It may also hold a liquid ejection head that ejects clear (transparent) coating paint, so that coating can be applied simultaneously with printing.

[0095] The carriage 831 is also provided with a first Z-direction driver 838 that moves the carriage 831 in the Z direction (the liquid ejection direction, which is the direction toward and away from the ejection target U2) along the Z-rail 835. The carriage 831 is also provided with a Y-direction driver 836 that moves the Z-rail 835 in the Y direction (the horizontal direction, which is perpendicular to both the liquid ejection direction and the nozzle arrangement direction of the liquid ejection head) along the Y-rail 833. The carriage 831 is also provided with an X-direction driver 837 that moves the Y-rail 833 in the X direction (the nozzle arrangement direction of the liquid ejection head, which is the vertical direction) along the X-rail 834. The Y-rail 833 is supported by the X-direction driver 837 that is held by each X-rail 834. The carriage 831 is also provided with a second Z-direction driver 839 that moves the head holder 832 in the Z direction relative to the carriage 831.

[0096] In this inkjet printer 830, paint is ejected from a liquid ejection head provided on a head holder 832 while a carriage 831 is moved in the X-, Y-, and Z-axis directions, to draw on an ejection target U2. Here, the movement of the carriage 831 and head holder 832 in the Z direction does not need to be parallel to the Z direction, and may be oblique movement as long as it includes at least a Z-directional component. Furthermore, if the liquid ejection head has a single nozzle row, the liquid ejection head may be held on the carriage 110 so as to be tiltable with respect to the X-direction, making the nozzle pitch variable.

[0097] FIG. 20 is a schematic perspective view showing yet another example of an inkjet printer as a device for ejecting liquid. 20 is, for example, an unmanned vehicle that can travel on a road surface, and can move on a road surface U3 such as a roadway or sidewalk by driving wheels 871. A liquid (e.g., paint) stored in a liquid tank 873 is supplied to a liquid discharge unit 872 having a liquid discharge head of this embodiment via a cable 874. Paint is discharged from the liquid discharge unit 872 toward the road surface U3, and a coating portion P of the road surface U3 is formed with, for example, a crosswalk, a stop line, a center line, etc.

[0098] Next, an electrode manufacturing apparatus will be described as another example of an apparatus for discharging liquid that includes the liquid discharge head of this embodiment.

[0099] FIG. 21 is a schematic perspective view showing an example of an electrode manufacturing apparatus 850. As shown in FIG. 21 is an apparatus for manufacturing negative electrodes used in electrochemical elements such as primary batteries, secondary batteries, capacitors, condensers, etc. The electrode manufacturing apparatus 850 is equipped with a liquid ejection unit 852 having the liquid ejection head 10 of this embodiment, and ejects liquid onto a negative electrode substrate U4 on a stage 851 using an inkjet method.

[0100] Liquid tank 853 contains liquid composition D 1 for forming negative electrode composite material layer 855 , and liquid composition D 1 is supplied from liquid tank 853 to liquid discharge unit 852 via tube 854 .

[0101] FIG. 22 is a schematic perspective view showing another example of an electrode manufacturing apparatus 850. As shown in FIG. 22, an electrode manufacturing apparatus 850 winds a strip-shaped negative electrode substrate U4 made of stainless steel, copper, or the like around a cylindrical core, and loads the electrode substrate U4 between a feed roller 857 and a take-up roller 859 with the surface on which the negative electrode composite layer 855 is to be formed facing upward. The feed roller 857 and the take-up roller 859 rotate counterclockwise, and the negative electrode substrate U4 moves from right to left in the drawing.

[0102] Liquid tank 853 contains liquid composition D1 for forming negative electrode composite layer 855, and supplies liquid composition D1 from liquid tank 853 to liquid discharge unit 852 via tube 854. Liquid discharge unit 852 is installed above negative electrode substrate U4 between delivery roller 857 and take-up roller 859. Furthermore, a plurality of liquid discharge units 852 may be installed in a direction substantially parallel to or substantially perpendicular to the transport direction of negative electrode substrate U4.

[0103] A delivery roller 857 and a take-up roller 859 transport the negative electrode substrate U4 carrying the liquid composition D1 to a drying device 858. As a result, the liquid composition D1 on the negative electrode substrate U4 is dried by the drying device 858 to form a negative electrode mixture layer 855, and a negative electrode 856 is formed in which the negative electrode mixture layer 855 is bonded to the negative electrode substrate serving as the negative electrode substrate U4. Thereafter, the negative electrode 856 is cut to a desired size by punching or the like.

[0104] The drying device 858 is not particularly limited as long as it does not come into direct contact with the liquid composition D1, and can be selected appropriately. Examples include a resistance heater, an infrared heater, and a fan heater. The drying device 858 may be installed either above or below the negative electrode substrate U4. Furthermore, multiple drying devices 858 may be installed.

[0105] While the above description has been given as an example of an apparatus for manufacturing a negative electrode for use in an electrochemical element, it is of course also applicable to an apparatus for manufacturing a positive electrode. When manufacturing a positive electrode, the electrode substrate for a negative electrode is replaced with an electrode substrate for a positive electrode, and liquid composition D1 for forming negative electrode composite layer 855 is replaced with a liquid composition for forming a positive electrode composite layer. Furthermore, the components other than the electrode composite layer in the electrochemical element are not particularly limited, and known components can be appropriately selected, such as a positive electrode, a negative electrode, and a separator.

[0106] Alternatively, an external tank may be provided and a valve may be controlled so that when the liquid composition D1 in the liquid tank 853 decreases, the liquid composition D1 is supplied from the external tank 860 to the liquid tank 853.

[0107] Although the preferred embodiments of the present invention have been described above, the present invention is not limited to such specific embodiments, and unless otherwise specifically limited in the above description, various modifications and variations are possible within the spirit and scope of the present invention as set forth in the claims.

[0108] In the above description, an embodiment has been described in which the needle valve 17 is opened and closed by the piezoelectric element 18. However, the present invention is not limited to this, and the needle valve 17 may be opened and closed by air pressure or hydraulic pressure. In this case, the drive pulse generated by the drive control device 40 is a drive waveform for driving the air pressure or hydraulic pressure pressurizing mechanism at a set pressure.

[0109] In this application, a "liquid ejection device" refers to a device that includes a liquid ejection head or a liquid ejection unit in which functional components and mechanisms are integrated with the liquid ejection head, and that ejects liquid by driving the liquid ejection head. The above-mentioned integration includes, for example, a device in which the liquid ejection head and the functional components or mechanisms are fixed to each other by fastening, bonding, engaging, etc., or a device in which one is held movably relative to the other. The liquid ejection head and the functional components or mechanisms may also be detachable from each other.

[0110] There are liquid ejection units in which the liquid ejection head and head tank are integrated, and in which the two are integrated by being connected to each other by a tube, etc. Here, it is also possible to add a unit including a filter between the liquid ejection head and head tank of these liquid ejection units.

[0111] There are liquid ejection units in which the liquid ejection head and carriage are integrated, and liquid ejection units in which the liquid ejection head, carriage, and scanning movement mechanism are integrated, and there are liquid ejection units in which the liquid ejection head is movably held by a guide member that constitutes part of the scanning movement mechanism, and the liquid ejection head and scanning movement mechanism are integrated.

[0112] Some liquid ejection units integrate the liquid ejection head, carriage, and maintenance and recovery mechanism by fixing a cap member, which is part of the maintenance and recovery mechanism, to a carriage on which the liquid ejection head is attached. Other liquid ejection units integrate the liquid ejection head and supply mechanism by connecting a tube to the liquid ejection head, which is equipped with a head tank or flow path components. Liquid from a liquid storage source is supplied to the liquid ejection head via this tube.

[0113] The scanning movement mechanism includes the guide member alone, and the supply mechanism includes the tube alone and the loading unit alone.

[0114] The term "device for ejecting liquid" includes not only a device that can eject liquid onto an object onto which the liquid can adhere, but also a device that ejects liquid into air or liquid.

[0115] This "liquid ejection device" can also include means for feeding, transporting, and discharging items onto which liquid can be attached, as well as pre-processing devices and post-processing devices.

[0116] For example, examples of "liquid ejecting devices" include image forming devices that eject ink to form images on paper, and three-dimensional modeling devices (three-dimensional modeling devices) that eject modeling liquid onto a powder layer formed from layers of powder in order to create a three-dimensional object (a three-dimensional model).

[0117] Furthermore, the term "liquid ejection device" is not limited to devices that use ejected liquid to visualize meaningful images such as letters and figures. For example, it also includes devices that form patterns that have no meaning in themselves, and devices that create three-dimensional images.

[0118] The above-mentioned "object onto which liquid can adhere" refers to the aforementioned object onto which liquid is ejected, and means an object onto which liquid can adhere at least temporarily, an object onto which the liquid adheres and sticks, an object onto which the liquid adheres and penetrates, etc. Specific examples include media such as paper, recording paper, film, and cloth, electronic circuit boards, electronic components such as piezoelectric elements, powder layers, organ models, and test cells, and unless otherwise specified, includes all objects onto which liquid can adhere.

[0119] The material of the "substance to which a liquid can adhere" may be any material to which a liquid can adhere, even temporarily, such as paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, or ceramics.

[0120] Furthermore, the "liquid ejection device" may be a device in which a head unit and an object onto which the liquid can be attached move relatively, but is not limited to this. Specific examples include a serial type device in which the head unit moves, and a line type device in which the head unit does not move.

[0121] Other examples of "liquid ejecting devices" include treatment liquid application devices that eject treatment liquid onto paper to apply the treatment liquid to the surface of the paper for purposes such as modifying the surface of the paper, and spray granulation devices that spray a composition liquid in which raw materials are dispersed through a nozzle hole to granulate fine particles of the raw materials.

[0122] Although the preferred embodiments of the present invention have been described above, the present invention is not limited to such specific embodiments, and unless otherwise specifically limited in the above description, various modifications and variations are possible within the spirit and scope of the present invention as set forth in the claims. For example, in the above description, the actuator unit of the present invention is applied to a mechanism that opens and closes the needle valve of a valve jet type liquid ejection head, but the actuator unit of the present invention can be applied to any moving mechanism that moves a moving member back and forth within a predetermined range, not limited to valve jet type liquid ejection heads.

[0123] The above description is merely an example, and each of the following aspects provides unique effects. (Aspect 1) In the actuator unit 58, which includes an actuator such as a piezoelectric element 18 and an amplifying mechanism that amplifies the displacement of the actuator to move a moving member such as a needle valve 17, the amplifying mechanism has a pair of arm members 21 that rotate in conjunction with the displacement of the actuator, and a connecting member such as a leaf spring member 30 that connects the pair of arm members 21 and the moving member such as the needle valve 17, and when viewed from the rotation axis direction (X direction) of the arm members, the connecting member is oriented in an orthogonal direction (Y direction) that is perpendicular to the movement direction (Z direction) of the moving member with respect to the moving member of one arm member. The arm member has a first connecting portion such as an inclined portion 32 that connects one end of the arm member to the movable member, and a second connecting portion such as an inclined portion 32 that connects the other end of the other arm member in the perpendicular direction to the movable member, and the pair of arm members are arranged so that, when viewed from the rotation axis direction (X direction), the fulcrum of rotation of one arm member coincides with the fulcrum of rotation of the other arm member, or so that a line connecting the fulcrum of rotation of one arm member to the connection part with the first connection part of the one arm member intersects with a line connecting the fulcrum of rotation of the other arm member to the connection part with the second connection part of the other arm member. In the inverse spring mechanism with a trapezoidal deformation part described in Patent Document 1, the longer the distance between the connection point with the fixed part, which is the fulcrum for the rotation of the lower base, and the end of the lower base, the greater the amount of movement of the end of the lower base toward the actuator in response to the displacement of the actuator. As a result, the amount of movement of the upper base, which is the deformation part connected to the end of the lower base via the left and right sides, toward the actuator increases, and the amount of movement of the moving member, which is the valve body connected to the upper base, toward the actuator can be increased. However, the lower base of the deformation portion becomes longer, and the actuator unit becomes larger in size in the direction perpendicular to the moving direction of the moving member. Therefore, in aspect 1, the amplification mechanism is configured with a pair of arm members that rotate in conjunction with the displacement of the actuator, and a connecting member that connects the pair of arm members and the moving member. The connecting member is provided with a first connecting portion that connects one end of one arm member to the moving member, and a second connecting portion that connects the other end of the other arm member to the moving member. This allows the pair of arm members and the connecting member to have the same function as the inverse spring mechanism of Patent Document 1, and when the actuator is displaced, the pair of arm members rotate in the same way as the lower base of the inverse spring mechanism, and the moving members connected to the ends of each arm member by the connecting member can be pulled toward the actuator and moved toward the actuator. Furthermore, in aspect 1, by configuring the portion corresponding to the lower base of the deforming portion of Patent Document 1 with a pair of arm members, it is possible to overlap one arm member with the other arm member as follows: That is, when viewed from the direction of the rotation axis, the pair of arm members are overlapped so that the fulcrum of rotation of one arm member and the fulcrum of rotation of the other arm member coincide with each other, or so that a line connecting the fulcrum of rotation of one arm member and the connection part with the first connection part of one arm member intersects with a line connecting the fulcrum of rotation of the other arm member and the connection part with the second connection part of the other arm member. This makes it possible to increase the distance between the pivot point and the connecting member of the arm member while preventing the actuator from becoming too large in the orthogonal direction, thereby preventing the actuator unit from becoming too large and increasing the amount of movement of the moving member in response to the displacement of the actuator.

[0124] (Aspect 2) In the actuator unit 58, which includes an actuator such as a piezoelectric element 18 and an amplification mechanism that amplifies the displacement of the actuator to move a moving member such as a needle valve 17, the amplification mechanism has a pair of arm members 21 that rotate in conjunction with the displacement of the actuator, and a connecting member such as a leaf spring member 30 that connects the pair of arm members 21 and the moving member such as the needle valve 17, and when viewed from the rotation axis direction (X direction) of the arm members, the connecting member has an inclined portion 32 that connects the moving member to one end on one side in the orthogonal direction (Y direction) that is orthogonal to the movement direction (Z direction) of the moving member with respect to the moving member of one arm member. and a second connection portion such as inclined portion 32 that connects the other end of the other arm member in the orthogonal direction to the moving member, and the pair of arm members are arranged overlapping each other so that, when viewed from the rotation axis direction (X direction), the displacement receiving portion 21c that receives displacement from the actuator of one arm member and the displacement receiving portion 21c that receives displacement from the actuator of the other arm member are aligned, or so that a line connecting the connection portion between the displacement receiving portion 21c of one arm member and the first connection portion of one arm member intersects with a line connecting the connection portion between the displacement receiving portion 21c of the other arm member and the second connection portion of the other arm member. As described in Modification 1, this prevents the actuator from becoming larger in the orthogonal direction compared to when the pair of arm members do not overlap, and prevents a decrease in the amount of movement of the moving member relative to the displacement of the actuator.

[0125] (Aspect 3) In aspect 1 or 2, the arm member 21 has an arm portion 21a, a fixed portion 21b fixed to the device, a displacement receiving portion 21c that receives displacement from an actuator such as a piezoelectric element 18, a fixed connecting portion 21d that connects the fixed portion 21b and the arm portion 21a, and a displacement connecting portion 21e that connects the displacement receiving portion 21c and the arm portion 21a, and the arm member 21 is configured so that at least the fixed connecting portion 21d and the displacement connecting portion 21e elastically deform to rotate the arm portion 21a, and when the width of the fixed connecting portion 21d is Bw and the thickness of the fixed connecting portion 21d is Bt, (Bw / Bt) is 0.05 or more and 1.5 or less, and when the width of the displacement connecting portion 21e is Cw and the thickness of the displacement connecting portion 21e is Ct, (Cw / Ct) is 0.05 or more and 1.5 or less. As described in the embodiment, this configuration minimizes elastic deformation of the fixed connecting portion 21d and the displacement connecting portion 21e, thereby preventing damage to the arm member due to plastic deformation caused by stress concentrated at the connecting points of the connecting portions 21d, 21e. This prevents a decrease in durability of the arm member 21. Furthermore, the elastic deformation of the fixed connecting portion 21d and the displacement connecting portion 21e is moderate, preventing a decrease in responsiveness and enabling high-frequency driving. It also prevents a decrease in the amount of movement of moving members such as the needle valve 17. Furthermore, by suppressing elastic deformation of the fixed connecting portion 21d, a decrease in the function of the arm portion as a fulcrum of leverage can be suppressed, and a decrease in the amount of deformation at the point of application c can be suppressed.

[0126] (Aspect 4) In any of aspects 1 to 3, in a direction (Y direction) perpendicular to both the rotation axis direction (X direction) of the arm member 21 and the movement direction (Z direction) of a movable member such as the needle valve 17, the fulcrum of rotation of the arm member is located between a force point a of the arm member that is pushed in by the displacement of an actuator such as the piezoelectric element 18, and a point of action c of the arm member that applies the displacement of the actuator to the movable member. As described in the embodiment, when the force point of the arm member is displaced to one side in the moving direction of the movable member such as the needle valve 17 due to the displacement of a piezoelectric element such as an actuator, the action point of the arm member is displaced to the other side in the moving direction of the movable member such as the needle valve 17, and the movable member can be moved in the opposite direction to the displacement direction of the actuator.

[0127] (Aspect 5) In any of aspects 1 to 4, in a direction (Y direction) perpendicular to both the rotation axis direction (X direction) of the arm member 21 and the movement direction (Z direction) of a movable member such as the needle valve 17, a force point a of the arm member that is pushed in by the displacement of the actuator is located between the fulcrum of the rotation of the arm member 21 and a point of application c of the arm member 21 that applies the displacement of the actuator such as the piezoelectric element 18 to a movable member such as the needle valve 17. According to this, as explained in the second modified example, when the force point portion of the arm member 21 is displaced to one side in the movement direction of the movable member such as the needle valve 17 due to the displacement of the piezoelectric element 18 such as the actuator, the action point portion of the arm member 21 is displaced to one side in the movement direction of the movable member such as the needle valve 17, and the movable member can be moved in the same direction as the displacement direction of the actuator.

[0128] (Aspect 6) In any of the aspects 1 to 5, the fixing portions 21b of the pair of arm members 21 fixed to the device are arranged so as to at least partially overlap when viewed from the rotation axis direction (X direction) of the arm members. As a result, as explained in Modification 3, it becomes possible to fix the fixed portions 21b of the pair of arm members with a single fixing member such as a single fixed shaft 64, thereby reducing the number of parts and the cost of the device.

[0129] (Aspect 7) In any of aspects 1 to 6, a connecting member such as a leaf spring member 30 is provided to connect a pair of arm members and a movable member such as a needle valve 17, and the thickness of the peripheral portion of the mounting portion such as the slit portion 21f to which the connecting member of at least one of the arm members is attached is made thicker than other portions. This makes it possible to increase the rigidity around the attachment portion, such as the slit portion 21f of the arm member, and suppress deformation around the attachment portion, as described in Modification Example 4. This makes it possible to suppress twisting of the connecting part, such as the leaf spring member 30, around the movement direction of the moving member, and stabilize the movement of the moving member.

[0130] (Aspect 8) In any of the first to seventh aspects, a transmission member 65 is provided that transmits the displacement of an actuator such as a piezoelectric element 18 to each of the pair of arm members 21. This makes it possible to make the displacement transmitted to each arm member 21 uniform compared to when each arm member 21 is directly joined to an actuator such as a piezoelectric element, as explained in Modification 5. This makes it possible to prevent differences in the amount of output displacement of each arm member 21, and allows moving members such as the needle valve 17 to move stably and straight.

[0131] (Aspect 9) In any of the first to eighth aspects, an actuator such as a piezoelectric element 18 and restriction members 67a, 67b that restrict the positions of the pair of arm members 21 are provided. This allows for improved positional accuracy between the actuator such as the piezoelectric element 18 and each arm member 21 compared to when the positions of the actuator such as the piezoelectric element 18 and each arm member 21 are restricted by different members, as described in variant example 6.

[0132] (Aspect 10) In a liquid ejection head 10 equipped with a valve member such as a needle valve 17 that opens and closes the nozzle 14, and an actuator unit 58 that moves the valve member between an open position that opens the nozzle 14 and a closed position that blocks the nozzle 14, any of the actuator units of embodiments 1 to 9 was used as the actuator unit. According to this, as explained in the embodiment, it is possible to prevent the liquid ejection head from becoming large, and to increase the size of the liquid droplets ejected from the nozzles.

[0133] (Aspect 11) In a liquid ejection device equipped with the liquid ejection head 10, the liquid ejection head of embodiment 10 was used as the liquid ejection head. This makes it possible to suppress an increase in the size of the device and to eject large droplets. [Explanation of symbols]

[0134] 10: Liquid ejection head 11: Housing 11a: Storage section 12: Supply port 13: Collection port 14: Nozzle 15: Nozzle plate 16: Flow path 17: Needle valve 18: Piezoelectric element 19: Piezoelectric element control member 21: Arm member 21a: Arm section 21b: Fixed part 21b1: Fitting hole 21c: Displacement receiving part 21d: Fixed connection part 21e: Displacement connection 21f: Slit section 21g: Thick part 22: O-ring 29: Connector 30: Leaf spring material 31: Valve connection part 32: Inclined part 33: Arm connection part 40: Drive control device 41: Waveform generating circuit 58: Actuator unit 60: Head unit 63: Holder 63a: Restriction hole 63b: Piezoelectric element fixing part 64: Fixed axis 65: Transmission component 67a: Regulating member 67b: Regulating member 68: Regulatory axis 810: Inkjet printer 830: Inkjet printer 850: Electrode manufacturing equipment Ah: Height of arm Aw: Distance from one arm member to the other arm member Pw: Overlap width of a pair of arm members Sh: Height of the leaf spring member a: emphasis b :Fulcrum c: Point of action [Prior art documents] [Patent documents]

[0135] [Patent Document 1] Japanese Patent Application Publication No. 2023-95912

Claims

1. An actuator; an amplification mechanism that amplifies the displacement of the actuator to move the moving member, the amplification mechanism includes a pair of arm members that rotate in conjunction with the displacement of the actuator, and a connection member that connects the pair of arm members and the moving member, When viewed from the rotation axis direction of the arm members, the connecting member has a first connecting portion that connects an end portion of one arm member on one side in an orthogonal direction perpendicular to the movement direction of the moving member with respect to the moving member of the one arm member, and the moving member, and a second connecting portion that connects an end portion of the other arm member on the other side in the orthogonal direction with the moving member, an actuator unit characterized in that, when viewed from the direction of the rotation axis, a pair of arm members are arranged to overlap each other so that the fulcrum of rotation of one arm member and the fulcrum of rotation of the other arm member coincide with each other, or so that a line connecting the fulcrum of rotation of one arm member and the connection part of the one arm member with the first connection part intersects with a line connecting the fulcrum of rotation of the other arm member and the connection part of the other arm member with the second connection part.

2. An actuator; an amplification mechanism that amplifies the displacement of the actuator to move the moving member, the amplification mechanism includes a pair of arm members that rotate in conjunction with the displacement of the actuator, and a connection member that connects the pair of arm members and the moving member, When viewed from the rotation axis direction of the arm members, the connecting member has a first connecting portion that connects an end portion of one arm member on one side in an orthogonal direction perpendicular to the movement direction of the moving member with respect to the moving member of the one arm member, and the moving member, and a second connecting portion that connects an end portion of the other arm member on the other side in the orthogonal direction with the moving member, an actuator unit characterized in that, when viewed from the direction of the rotation axis, a pair of arm members are arranged to overlap each other so that a displacement receiving portion of one arm member that receives displacement from the actuator and a displacement receiving portion of the other arm member that receives displacement from the actuator are coincident, or so that a line connecting the displacement receiving portion of one arm member and the connection portion of the first connection portion of the one arm member intersects with a line connecting the displacement receiving portion of the other arm member and the connection portion of the second connection portion of the other arm member.

3. 3. The actuator unit according to claim 1, the arm member has an arm portion, a fixed portion fixed to an apparatus, a displacement receiving portion that receives displacement from the actuator, a fixed connecting portion that connects the fixed portion and the arm portion, and a displacement connecting portion that connects the displacement receiving portion and the arm portion, The arm member is configured so that at least the fixed connecting portion and the displacement connecting portion are elastically deformed to rotate the arm portion, When the width of the fixed connecting portion is Bw and the thickness of the fixed connecting portion is Bt, (Bw / Bt) is 0.05 or more and 1.5 or less, An actuator unit characterized in that, when the width of the displacement connecting portion is Cw and the thickness of the displacement connecting portion is Ct, (Cw / Ct) is 0.05 or more and 1.5 or less.

4. 3. The actuator unit according to claim 1, an actuator unit characterized in that a fulcrum of rotation of the arm member is located between a force point of the arm member that is pushed in by the displacement of the actuator and a point of application of the arm member that applies the displacement of the actuator to the movable member, in a direction perpendicular to both the rotation axis direction of the arm member and the movement direction of the movable member.

5. 3. The actuator unit according to claim 1, an actuator unit characterized in that a force point of the arm member that is pushed in by the displacement of the actuator is located between a fulcrum of rotation of the arm member and a point of application of the arm member that applies the displacement of the actuator to the movable member, in a direction perpendicular to both the rotation axis direction of the arm member and the movement direction of the movable member.

6. 3. The actuator unit according to claim 1, An actuator unit characterized in that the fixing portions of the pair of arm members fixed to the device are arranged so as to at least partially overlap when viewed from the direction of the rotation axis of the arm members.

7. 3. The actuator unit according to claim 1, a connecting member that connects the pair of arm members and the moving member; An actuator unit characterized in that the thickness of a peripheral portion of a mounting portion to which the connecting member of at least one of the arm members is attached is made thicker than the thickness of other portions.

8. 3. The actuator unit according to claim 1, An actuator unit comprising a transmission member for transmitting the displacement of the actuator to each of the pair of arm members.

9. 3. The actuator unit according to claim 1, An actuator unit comprising a restricting member that restricts the positions of the actuator and the pair of arm members.

10. a valve member for opening and closing the nozzle; a liquid ejection head including an actuator unit that moves the valve member between an open position that opens the nozzle and a closed position that closes the nozzle, 3. A liquid ejection head, comprising the actuator unit according to claim 1 or 2 as the actuator unit.

11. In a liquid ejection device equipped with a liquid ejection head, 11. A liquid ejection device, comprising the liquid ejection head according to claim 10.

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