Liquid discharge head and device for discharging liquid

Abstract

To provide a liquid discharge head and a device for discharging liquid that can improve the responsiveness of a valve member.SOLUTION: A liquid discharge head includes: a needle valve 17 being a valve member that opens / closes a nozzle for discharging liquid; and a movement mechanism that has an actuator and moves the needle valve 17 between an open position where the nozzle is opened by displacement of the actuator and a closed position where the nozzle is closed. The movement mechanism includes a plate spring member 30 that is connected to the needle valve 17 and biases the needle valve 17 toward the nozzle side when the needle valve 17 is located at the closed position. The plate spring member 30 includes: an inclined part 32 as an elastically deformable part that is elastically deformed to generate biasing force when the needle valve 17 is located at the closed position; and a valve connection part 31 that is formed by being bent from the inclined part 32 and connected to the needle valve 17. The valve connection part 31 is reinforced by a reinforcing member 51 being a reinforcing part.SELECTED DRAWING: Figure 5

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 is known which includes a valve member that opens and closes a nozzle for ejecting a liquid, and a moving mechanism having an actuator that moves the valve member between an open position where the nozzle is opened and a closed position where the nozzle is closed by displacement of the actuator.

[0003] Patent Document 1 describes a liquid ejection head of the above type, in which the moving mechanism includes a reverse spring mechanism formed by molding a rubber, a soft resin, or the like that can be appropriately deformed, or a thin metal plate or the like. The reverse spring mechanism includes a deformed portion having a substantially trapezoidal cross section formed so as to contact the actuator-side end portion of the valve body, a fixed portion fixed to the inner wall surface of the apparatus main body, and a guide portion connected to the end surface of the actuator. The valve body side of the deformed portion is the upper base of the trapezoid, and the actuator side is the lower base of the trapezoid. The actuator-side end portion of the valve body is connected to the upper base of the deformed portion, and the lower base of the deformed portion is connected to the fixed portion to form a bent side.

[0004] When the actuator is driven, the guide portion moves toward the nozzle side and presses the vicinity of the center of the bent side of the deformed portion. As a result, the peripheral portion of the bent side of the deformed portion is deformed so as to be drawn toward the actuator side. As a result, the upper base of the deformed portion connected to the valve body moves toward the actuator side. As a result, the valve body is attracted toward the actuator side and the discharge port is opened, and ink is discharged from the discharge port.

[0005] When the actuator is not driven, the deformed portion of the reverse spring mechanism is in a swollen state, and the valve body is urged in the direction of the discharge port by the elastic force of the deformed portion, and the discharge port is closed by the end surface of the valve body.

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, there was a risk that the responsiveness of the opening and closing of the valve member to the displacement of the actuator would deteriorate.

Means for Solving the Problem

[0007] In order to solve the above-described problems, the present invention provides a liquid discharge head including a valve member that opens and closes a nozzle for discharging a liquid, an actuator, and a movement mechanism that moves the valve member between an open position where the actuator displacement opens the nozzle and a closed position where the actuator displacement closes the nozzle. The movement mechanism includes a leaf spring member connected to the valve member and biasing the valve member toward the nozzle side when the valve member is in the closed position. The leaf spring member has an elastically deformable portion that elastically deforms to generate a biasing force when the valve member is in the closed position, and a valve connection portion formed by being bent from the elastically deformable portion and connected to the valve member, and is characterized by including a reinforcing portion that reinforces the valve connection portion.

Effect of the Invention

[0008] According to the present invention, the responsiveness of the valve member can be improved.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

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Figure 5

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Figure 8

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Figure 10

Figure 11

Figure 12

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Figure 14

Figure 15

Figure 16

Figure 17

Figure 18

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Figure 22

Figure 23

Best Mode for Carrying Out the Invention

[0010] The best mode for carrying out the present invention will be described below 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 this invention and does not limit the scope of the claims.

[0011] FIG. 1 is an overall perspective view of the liquid ejection head 10. In FIG. 1, the longitudinal direction (the arrangement direction of the nozzles 14) of the liquid ejection head 10 is defined as the X direction, the short-side direction of the liquid ejection head 10 is defined as the Y direction, and the height direction (the opening and closing direction of the needle valve 17, the moving direction of the needle valve 17, the liquid ejection direction from the nozzles 14) of the liquid ejection head 10 is defined as the Z direction. And it is assumed that the definition of this coordinate in the following figures is the same unless otherwise specified.

[0012] The liquid ejection head 10 includes a housing 11 that serves as a casing. The housing 11 is made of metal or resin. Further, the housing 11 is provided with a connector 29 for communication of electrical signals at its upper part. Also, at one end of the housing 11 in the X direction, there is a supply port 12 for supplying a liquid such as ink into the head, and at the other end in the X direction, there is a recovery port 13 for discharging the liquid from the head.

[0013] FIG. 2 is a schematic configuration diagram showing the head unit 60 and is also a view showing a cross section of the liquid ejection head 10 taken along the line A-A in FIG. 1. The head unit 60 has a liquid ejection head 10 and a drive control device 40.

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

[0015] With the above configuration, the supply port 12 takes in the pressurized liquid from the outside, sends the liquid in the direction of arrow a1, and supplies the liquid to the flow path 16. The flow path 16 sends the liquid from the supply port 12 in the direction of arrow a2. Then, the recovery port 13 discharges the liquid that has not been ejected from the nozzle 14 arranged along the 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. In this example, a configuration is shown that includes eight liquid ejection modules 70 corresponding to eight nozzles 14 arranged in a single row. Note that the number and arrangement of the nozzles 14 and the liquid ejection modules 70 are not limited to the above. For example, the number of the nozzles 14 and the liquid ejection modules 70 may be one instead of a plurality. Also, it may be eight or more or less than eight. And the arrangement of the nozzles 14 and the liquid ejection modules 70 may be arranged in multiple rows instead of a single row.

[0017] Each liquid ejection module 70 includes a needle valve 17 that is a valve member for opening and closing the nozzle 14, and a piezoelectric element 18 that is an actuator for driving the needle valve 17. By displacing the piezoelectric element 18, the needle valve 17 is opened and closed to eject the liquid from the nozzle 14.

[0018] Inside the housing 11, there are provided a plurality of accommodating portions 11a (see FIG. 3) in which the liquid ejection modules 70 are respectively accommodated. Inside each accommodating portion 11a, a piezoelectric element restricting member 19 is provided at a position facing the upper end portion of the piezoelectric element 18. This piezoelectric element restricting member 19 is in contact with the upper end portion of the piezoelectric element 18 and forms a fixing point of the piezoelectric element 18.

[0019] Between the accommodating portion 11a and the flow path 16, a through hole through which the needle valve 17 penetrates is formed, and an O-ring 22 (see FIG. 3) is provided in the through hole to seal between the through hole and the needle valve 17.

[0020] At the tip of the needle valve 17, a sealing member which is an elastic member is provided. When the sealing member of the needle valve 17 is pressed against the nozzle plate 15, the sealing member is compressed, so that the needle valve 17 surely closes the nozzle 14.

[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 a moving mechanism 58 described later. As a result, the needle valve 17 is separated from the nozzle 14 to open the nozzle 14. Thereby, the liquid pressurized and supplied to the flow path 16 is ejected from the nozzle 14. Also, when no voltage is applied to the piezoelectric element 18, the needle valve 17 closes the nozzle 14. In this state, even if the liquid is pressurized and supplied to the flow path 16, the liquid does not eject from the nozzle 14.

[0022] The drive control device 40 includes a waveform generation circuit 41 which is a drive pulse generation unit and an amplification circuit. The waveform generation circuit generates a drive pulse waveform described later, and the amplification circuit amplifies the voltage value to a required value. Then, the amplified voltage is 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 and controls the ejection of the liquid from the liquid ejection head 10. However, when the waveform generation circuit can apply a voltage of a sufficient value, the amplification circuit may be omitted.

[0023] The waveform generation circuit 41 generates drive pulses, which are waveforms of the voltage applied to the piezoelectric element 18 over time. The waveform generation circuit receives print data from an external PC or a microcomputer inside the device and generates drive pulses based on this input data. The waveform generation circuit can change the voltage applied to the piezoelectric element 18 and can generate a plurality of drive pulses. As described above, when the waveform generation circuit generates drive pulses, the piezoelectric element 18 expands and contracts according to the drive pulses, causing the needle valve 17 to move open and closed.

[0024] FIG. 3 is a schematic configuration diagram showing the basic configuration of the liquid ejection module 70. FIG. 3(a) is a schematic configuration diagram showing the state where the needle valve 17 closes the nozzle 14, and FIG. 3(b) is a schematic configuration diagram showing the state where the needle valve 17 opens the nozzle 14. The liquid ejection module 70 is housed in the housing portion 11a of the housing 11 and includes a needle valve 17, which is a valve member that opens and closes the nozzle 14, and a movement mechanism 58. The movement mechanism 58 includes a piezoelectric element 18, a moving member 20, a pair of arm members 21, and a leaf spring member 30. One end of the moving member 20 is fixed to the piezoelectric element 18, and a pair of arm members 21 are rotatably attached to the other end. The moving member 20 is movably attached in the Z direction to a holder 63 that holds the piezoelectric element 18. The pair of arm members 21 are rotatably supported by a support shaft 21a attached to the holder 63.

[0025] The leaf spring member 30 is formed by bending a sheet metal made of SUS, and forms a valve connection portion 31 connected to the needle valve 17, a pair of inclined portions 32 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 inclined portions 32 as elastic deformation portions extend obliquely upward in the drawing from both ends of the valve connection portion 31. The arm connection portion 33 is fitted into a slit portion provided in the arm member 21 and attached to the arm member 21.

[0026] As shown in FIG. 3(a), when the needle valve 17 closes the nozzle 14 (when the needle valve 17 is in the closed position), a pair of inclined portions 32 of the leaf spring member 30 are elastically deformed as shown by the broken line in the figure, generating a biasing force that presses the needle valve 17 against the nozzle plate 15.

[0027] As shown by the black arrow in FIG. 3(b), when the piezoelectric element 18 is displaced toward the nozzle 14, the moving member 20 moves toward the nozzle side, pushing the pair of arm members 21 into the nozzle side. As a result, the pair of arm members 21 rotate about the support shaft 21a as a fulcrum. When the pair of arm members 21 rotate, both ends of the leaf spring member 30 move in a direction away from each other. Thereby, the needle valve 17 is lifted, the nozzle 14 is opened, and liquid is discharged from the nozzle 14 (corresponding to the state where the needle valve 17 is in the open position where it opens the nozzle 14).

[0028] FIG. 4 is a diagram for explaining the operation when opening the nozzle 14 in the conventional liquid ejection module 70. FIG. 4(a) shows the state where the needle valve 17 closes the nozzle 14 (the state of being in the closed position), FIG. 4(c) shows the state where the needle valve opens the nozzle 14 (the state of being in the open position), and FIG. 4(b) shows the process of the needle valve 17 moving from the closed position to the open position. As shown in FIG. 4, the valve connection portion 31 of the leaf spring member 30 is bent from the nozzle-side end of the inclined portion 32 and provided so as to be orthogonal to the Z direction. As shown in FIG. 4(b), when both ends of the leaf spring member 30 move in a direction away from each other, a compressive force is applied to the valve connection portion 31 from each inclined portion 32. Then, conventionally, as shown by the arrow in FIG. 4(b), the portions of the valve connection portion 31 that are not joined to the needle valve 17 (both sides with reference to the valve through hole through which the needle valve in the center of the valve connection portion penetrates) are elastically deformed so as to curve.

[0029] Therefore, conventionally, the start of movement of the needle valve 17 from the closed position closing the nozzle 14 to the open position opening the nozzle 14 is as follows. That is, first, after the elastic deformation shown by the broken line in FIG. 3(a) of the inclined portion 32 of the leaf spring member 30 is eliminated, the valve connection portion 31 elastically deforms by a predetermined amount and then the movement of the needle valve 17 starts. As a result, the time lag from the start of driving of the piezoelectric element 18 until the needle valve 17 starts to move becomes long, and the responsiveness of the movement of the needle valve 17 to the driving of the piezoelectric element 18 is poor.

[0030] Also, when the needle valve 17 closes the nozzle 14, the valve connection portion 31 is elastically deformed so as to bend slightly by the urging force due to the elastic deformation of the inclined portion 32 shown by the broken line in FIG. 3, and this also becomes a factor deteriorating the responsiveness.

[0031] As described above, since the responsiveness of the movement of the needle valve 17 to the driving of the piezoelectric element 18 is poor, when the frequency of the driving waveform applied to the piezoelectric element 18 is increased to a high frequency, the movement of the needle valve 17 cannot follow the driving of the piezoelectric element 18. As a result, there is a possibility that the needle valve 17 cannot be opened and closed.

[0032] Therefore, in the present embodiment, a reinforcing member as a reinforcing portion for reinforcing the valve connection portion 31 of the leaf spring member 30 is provided to suppress the elastic deformation of the valve connection portion 31. Hereinafter, the characteristic portions of the present embodiment will be described with reference to the drawings.

[0033] FIG. 5 is an enlarged schematic configuration diagram showing the periphery of the leaf spring member 30 of the liquid discharge module 70 of the present embodiment. As shown in FIG. 5, in the present embodiment, it has a reinforcing member 51 as a reinforcing portion, and the valve connection portion 31 of the leaf spring member 30 is fitted into the slit portion 51a of the reinforcing member 51, and the valve connection portion 31 is clamped by the reinforcing member 51 in the Z direction.

[0034] FIG. 6 is an enlarged perspective view showing the reinforcing member 51 and the periphery of the valve connection portion 31 of the leaf spring member 30, and FIG. 7 is a diagram for explaining the fixing of the needle valve 17. The reinforcing member 51 is made of a material such as aluminum or titanium for weight reduction of the device. The slit portion 51a into which the valve connection portion 31 is fitted is provided at the center in the thickness direction of the reinforcing member 51. The thickness of the reinforcing member 51 is 2 mm to 3 mm. If the reinforcing member 51 has a thickness of about 1 mm with respect to the valve connection portion 31, the bending deformation of the valve connection portion 31 can be favorably suppressed.

[0035] The reinforcing member 51 is formed with a filling hole 51b into which the adhesive 35 is filled. The valve connection portion 31 of the leaf spring member 30 is fitted into the slit portion 51a so that the center of the valve through hole 31a through which the needle valve 17 provided in the valve connection portion 31 penetrates coincides with the center of the filling hole 51b of the reinforcing member 51. Next, after the piezoelectric element side of the needle valve 17 is passed through the valve through hole 31a, the needle valve 17 is fixed by filling the filling hole 51b with the adhesive 35. In the present embodiment, a heat-curing epoxy resin-based adhesive is used as the adhesive 35, but an ultraviolet-curing adhesive or the like may be used.

[0036] In the present embodiment, the needle valve 17 is fixed using the adhesive 35. However, for example, the reinforcing member 51 may be fixed to the needle valve 17 by screwing. However, the needle valve 17 and the reinforcing member 51 are small members, and it is difficult to form screw grooves in them, and the manufacturing cost may increase compared to the case of fixing with the adhesive 35. Also, there is a possibility that the weight may increase compared to the case of fixing with the adhesive 35. Therefore, it is preferable to fix the needle valve 17 with an adhesive.

[0037] Further, by providing the filling hole 51b for filling the adhesive 35 in the reinforcing member 51, the amount of the adhesive 35 can be quantified, and the adhesion range can be mechanically managed.

[0038] As shown in FIG. 7, the valve connection portion 31 is fitted into the slit portion 51a of the reinforcing member 51, so that the vicinity of the connection portion with the inclined portion 32 of the valve connection portion 31 is clamped and reinforced by the reinforcing member 51 in the moving direction (Z direction) of the needle valve 17. Further, the valve connection portion 31 is reinforced on both sides in the Z direction by a resin layer made of an adhesive 35 filled in the filling hole 51b of the reinforcing member 51. Thereby, when the needle valve 17 is moved to the open position, it is possible to suppress the valve connection portion 31 from elastically deforming so as to bend. Thereby, the responsiveness of the movement of the needle valve 17 with respect to the displacement of the piezoelectric element 18 can be improved. As a result, even when the frequency of the drive waveform applied to the piezoelectric element 18 is increased to a high frequency, the needle valve 17 can be moved following the drive waveform, and droplets can be ejected favorably.

[0039] In order to preferably suppress the bending elastic deformation of the valve connection portion 31, it is preferable to reinforce the entire valve connection portion 31 with a resin layer composed of the reinforcing member 51 and the adhesive 35 as much as possible. Therefore, as shown in FIG. 7, the outer end portion of the reinforcing member 51 is preferably positioned in the range of ±0.1 mm in the left-right direction in the figure with respect to the intersection O1 (center of the bending R) of the inner bending allowance and the outer bending allowance of the bending portion between the valve connection portion 31 and the inclined portion 32 as a reference point. If the outer end portion of the reinforcing member 51 is positioned more than 0.1 mm outside with respect to the intersection O1, the outer end portion of the reinforcing member 51 may contact the inclined portion 32.

[0040] FIG. 8 is a graph showing the lift amount from the closed position of the needle valve 17 when a drive pulse for gradually increasing the voltage from 0 V to 24 V is input to the piezoelectric element 18. As shown in FIG. 8, the lift amount when the applied voltage is 6 to 12 V at the initial stage of applying the drive pulse to the piezoelectric element 18 increased by providing the reinforcing member 51. This is because, by providing the reinforcing member 51 and reinforcing the valve connection portion 31 of the leaf spring member 30, as described with reference to FIG. 4 above, the bending elastic deformation of the valve connection portion 31 at the start of driving is suppressed. As a result, the start of movement of the needle valve 17 from the closed position is earlier than when there is no reinforcing member 51, and it is considered that the lift amount at 6 to 12 V at the initial stage of applying the drive pulse is larger than when there is no reinforcing member 51.

[0041] Figure 9 is a graph comparing the pushing loads on the piezoelectric element 18 when the reinforcing member 51 is present and when it is absent. The left side in the figure is the pushing load when the reinforcing member 51 is provided, and the right side in the figure is the pushing load when the reinforcing member 51 is not provided. The pushing load is the load when the piezoelectric element 18 is pushed toward the nozzle side after the needle valve 17 is positioned at the closed position and pushed until no liquid leaks from the nozzle 14. Also, in Figure 9, the needle valve 17 and the valve connection portion 31 were fixed with an adhesive, the pushing load was measured, then the reinforcing member 51 was attached, and the pushing load was measured again. These load measurements are the results for 15 liquid ejection modules 70.

[0042] As shown in Figure 9, by providing the reinforcing member 51, the pushing load on the piezoelectric element 18 was suppressed, and the nozzle 14 could be sealed with a small pushing load. This is because by providing the reinforcing member 51, the deformation of the valve connection portion 31 is suppressed, and the biasing force due to the elastic deformation of the inclined portion 32 of the leaf spring member 30 being absorbed by the bending elastic deformation of the valve connection portion 31 is suppressed. As a result, it is considered that the nozzle 14 could be sealed with a small pushing load.

[0043] The fact that the pushing load is small means that the piezoelectric element 18 is located further away from the nozzle 14, and the elastic deformation amount of the inclined portion 32 when the nozzle is closed is small. As a result, when the needle valve 17 is moved from the closed position to the open position, the elastic deformation (flexure) of the inclined portion 32 is quickly eliminated, the time lag from the start of driving until the needle valve 17 starts to move is shortened, and the responsiveness is improved. Also, the fact that the elastic deformation amount of the inclined portion 32 when the nozzle is closed is small means that the time from the nozzle open state to the closed state is also shortened, and the responsiveness at the time of closing is also improved.

[0044] Figure 10 is a graph showing the displacement of the needle valve 17 when a predetermined drive pulse is applied to the piezoelectric element 18. As shown in FIG. 10, it can be seen that by providing the reinforcing member 51, the needle valve 17 quickly displaces from the nozzle closed position to the open position. Also, it can be seen that the needle valve 17 quickly displaces from the open position to the closed position as well.

[0045] As shown in FIG. 10, by providing the reinforcing member 51, the needle valve 17 quickly displaces from the nozzle closed position to the open position, and the time during which the needle valve 17 is located at the open position becomes longer compared to the case where the reinforcing member 51 is not provided. The amount of droplets discharged from the nozzle 14 increases as the time during which the needle valve 17 is located at the open position becomes longer. Therefore, by providing the reinforcing member 51, the amount of liquid of the droplets with respect to the voltage application time of the drive pulse can be increased. As a result, even if the voltage application time of the drive pulse is shorter than that of the case without the reinforcing member 51, droplets of a desired size can be discharged from the nozzle 14. Thereby, the frequency of the drive pulse can be increased.

[0046] Also, by providing the reinforcing member 51, the needle valve 17 can quickly displace from the open position to the closed position, and satellite droplets (trailing of droplets) can be suppressed. Also, by the needle valve 17 quickly displacing from the open position to the closed position, the pressure of the needle valve 17 applied to the droplets discharged from the nozzle 14 increases. Thereby, the speed of the droplets discharged from the nozzle 14 can be increased.

[0047] FIG. 11(a) is a diagram showing the flying state of the droplet T0 discharged from the nozzle 14 of the liquid discharge head 10 of the present embodiment provided with the reinforcing member 51. FIG. 11(b) is a diagram showing the flying state of the droplets discharged from the nozzle 14 of the liquid discharge head of the comparative example not provided with the reinforcing member 51. FIGS. 11(a) and 11(b) are diagrams observed from a direction orthogonal to the liquid discharge direction of the nozzle 14 of the liquid discharge head 10. The flying droplet T0 is discharged from the nozzle 14 located on the left side in the figure and flies along the Z direction which is the droplet discharge direction. As can be seen from the comparison between FIGS. 11(a) and 11(b), the droplets T0 ejected from the nozzle 14 of the liquid ejection head 10 of the present embodiment provided with the reinforcing member 51 have less trailing T of the droplets and a better droplet shape compared to the comparative example without the reinforcing member 51. The flight state of the droplet T0 and the trailing T of the droplet can be observed by photographing with a high-speed camera from a direction (such as the Y direction) orthogonal to the liquid ejection direction (Z direction) of the liquid ejection head 10. Alternatively, it is also possible to observe the droplet T0 and the trailing T of the droplet by photographing with a digital camera using a strobe issued in synchronization with the ejection frequency of the droplet.

[0048] In this way, by reinforcing the valve connection portion 31 of the leaf spring member 30 with the reinforcing member 51 and suppressing the elastic deformation of the valve connection portion 31, the responsiveness of the needle valve 17 to the displacement of the piezoelectric element 18 can be enhanced. As a result, even in the case of high-frequency driving, droplets can be ejected satisfactorily, and droplets with a good shape with suppressed trailing can be ejected from the nozzle 14.

[0049] [Modification Example 1] FIG. 12 is an enlarged perspective view of the periphery of the leaf spring member of the liquid ejection module 30A of Modification Example 1. As shown in FIG. 12, in Modification Example 1, a reinforcing member 52 is provided on the piezoelectric element 18 side with respect to the valve connection portion 31, and a reinforcing portion 34 made of resin formed with an adhesive is provided on the nozzle side with respect to the valve connection portion 31. Further, in this Modification Example 1, an assist spring 23 for assisting the biasing on the nozzle side of the needle valve 17 is provided.

[0050] By providing the assist spring 23, the pushing load on the piezoelectric element 18 can be reduced, and the nozzle 14 can be sealed so that liquid does not leak from the nozzle 14 at a position where the piezoelectric element 18 is separated from the nozzle side. Thereby, the elastic deformation of the inclined portion 32 of the leaf spring member 30 can be suppressed, and the responsiveness can be further improved.

[0051] FIG. 13 is a schematic configuration diagram of the reinforcing member 52 used in Modification 1, (a) is a perspective view, (b) is a plan view, and (c) is a side view. The reinforcing member 52 used in Modification 1 has a cylindrical shape, and a valve press-fitting hole 52b into which the needle valve 17 is lightly press-fitted is provided at the center thereof. Further, four filling holes 52a filled with an adhesive are provided around the valve press-fitting hole 52b. The filling holes 52a are arranged at intervals of 90° in the circumferential direction, and each filling hole 52a communicates with the valve press-fitting hole 52b.

[0052] By providing the valve press-fitting hole 52b into which the needle valve 17 is lightly press-fitted in the reinforcing member 52, the filling holes 52a can be filled with the adhesive without performing temporary fixing or the like, and the manufacturing cost can be reduced.

[0053] FIG. 14 is a diagram for explaining the fixing of the needle valve 17 in Modification 1. After passing the needle valve 17 through the valve through-hole 31a of the valve connection portion 31, the needle valve 17 is lightly press-fitted into the valve press-fitting hole 52b of the reinforcing member 52. Then, the filling holes 52a of the reinforcing member 52 are filled with an adhesive to adhesively fix the reinforcing member 52 and the valve connection portion 31 to the needle valve 17. Further, an adhesive is applied to the nozzle-side surface of the valve connection portion 31 and formed into a substantially trapezoidal cross-sectional shape as shown in FIG. 14 to form a reinforcing portion 34 made of resin.

[0054] As shown in FIG. 14, in Modification 1, the valve connection portion 31 of the leaf spring member 30 is reinforced in such a manner that it is sandwiched by the reinforcing portion 34 made of resin formed by the reinforcing member 52 and the adhesive. Thereby, also in Modification 1, the bending elastic deformation of the valve connection portion 31 can be favorably suppressed, and the responsiveness of the needle valve 17 can be improved. Further, in Modification 1, by forming the reinforcing portion 34 made of resin on the nozzle side with an adhesive, the number of parts can be reduced as compared with the case where the reinforcing portion 34 on the nozzle side is configured by a separate member, and the cost of the apparatus can be reduced.

[0055] In addition, in this Modification 1, the reinforcing portion 34 on the nozzle side is formed of an adhesive. However, as shown in FIG. 15, a configuration in which a reinforcing portion 37 on the nozzle side is provided on the needle valve 17 may be adopted. For example, the reinforcing portion 37 may be provided on the needle valve 17 by cutting or the like, or a separate member may be fixed to the needle valve 17 by welding, adhesion, or the like to provide the reinforcing portion 37 on the needle valve 17. As shown in FIG. 15, by providing the reinforcing portion 37 on the needle valve 17, the number of assembly steps can be reduced and an increase in manufacturing cost can be suppressed as compared with the case of a separate member for the reinforcing portion on the nozzle side.

[0056] Further, in the present embodiment, as described with reference to FIG. 4, the valve connection portion 31 elastically deforms so as to be curved in the Z direction. Specifically, the centers on both sides sandwiching the valve through-hole 31a of the valve connection portion 31 elastically deform toward the piezoelectric element side, and both ends of the valve connection portion 31 (connection portions with the inclined portions 32) elastically deform toward the nozzle side. Therefore, in order to reinforce the valve connection portion 31 so that it does not elastically deform as a separate member from the leaf spring member 30, it is necessary to provide reinforcing portions on both the nozzle side and the piezoelectric element side with respect to the valve connection portion 31 and sandwich and reinforce the valve connection portion 31. However, when the valve connection portion 31 elastically deforms only on either the nozzle side or the piezoelectric element side, a reinforcing portion may be provided on the side where the valve connection portion 31 elastically deforms.

[0057] Also, as shown in FIG. 16, a reinforcing portion 53 may be formed on the leaf spring member 30 by coining. Further, a reinforcing portion 54 shown in FIG. 17 may be formed by performing cutting on a sheet metal having a certain thickness. Specifically, after performing cutting while leaving the portion that will become the reinforcing portion 54, bending is performed to obtain the leaf spring member 30 having the shape shown in FIG. 17. In this way, by directly forming a reinforcing portion on the leaf spring member 30 (integrally forming the reinforcing portion with the same material as the leaf spring member 30), the valve connection portion 31 has the same thickness as the other portions of the leaf spring member 30, and the bending rigidity of the valve connection portion 31 can be increased compared to a case where the valve connection portion 31 is formed by bending (the other portions of the leaf spring member 30 and the valve connection portion 31 are integrally formed of the same material). Thereby, the bending elastic deformation of the valve connection portion 31 can be suppressed. Further, a reinforcing portion may be provided by welding to the valve connection portion 31 of the leaf spring member 30. The thickness of the reinforcing portion 54 shown in FIG. 17 and the length of the reinforcing portion 54 in the left-right direction in the figure may be appropriately set so that the valve connection portion 31 does not bend due to the load applied to the valve connection portion 31 when the needle valve 17 moves.

[0058] Also, when directly forming a reinforcing portion on the leaf spring member 30 (integrally forming the reinforcing portion with the same material as the leaf spring member 30), if the reinforcing portion is provided on either the nozzle side or the piezoelectric element side with respect to the valve connection portion 31, the elastic deformation of the valve connection portion 31 can be favorably suppressed.

[0059] The above-described liquid ejection head 10 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 discharge target in the distance (several tens of mm ahead). Further, the nozzle diameter can be increased, and a liquid containing a material with a large particle size can also be ejected well. Thus, since a highly viscous liquid can be ejected, the above-described liquid ejection head 10 is suitable for painting of vehicle bodies of cars and trucks, aircraft fuselages, building walls, road surfaces, etc., and printing of images. Further, it can also be suitably used for forming electrodes such as lithium ion batteries mounted on vehicle bodies.

[0060] Hereinafter, an example of an apparatus for ejecting a liquid having the above-described liquid ejection head 10 will be described.

[0061] FIG. 18 is a schematic configuration diagram of an inkjet printer 810 as a device for discharging a liquid, and FIG. 19 is a perspective view showing an arrangement example of the inkjet printer 810 with respect to an automobile U1. As shown in FIG. 18, the inkjet printer 810 includes a liquid discharge unit 100 having a liquid discharge head, and a camera 812 as imaging means disposed in the vicinity of the liquid discharge unit 100. Further, it includes an X-Y table 811 as a scanning movement mechanism for moving the liquid discharge unit 100 and the camera 812 in the X direction and the Y direction.

[0062] The inkjet printer 810 also includes a control unit 600. The control unit 600 operates the X-Y table 811 based on image editing software S for editing an image captured by the camera 812 and a preset control program to discharge ink from the liquid discharge 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 discharge unit 100 at predetermined positions based on control from the control unit 600 to perform imaging and printing operations.

[0063] The liquid discharge unit 100 includes a plurality of liquid discharge heads that discharge ink toward a surface to be painted of an automobile U1 (see FIG. 19) as an object to be painted. Here, the "ink" is assumed to include "paint". The nozzle surface of the liquid discharge head is parallel to the X-Y plane formed by the movement of the X-Y table 811, and ink dots discharged from each nozzle are discharged in the Z direction perpendicular to the X-Y plane.

[0064] The plurality of liquid discharge heads included in the liquid discharge unit 100 are each connected to an ink tank of a predetermined color, and the ink tank is pressurized by a pressurizing device. The ink in the ink tank is supplied from a supply port 12 (see FIG. 1) of the liquid discharge head and discharged from a recovery port 13 (see FIG. 1) of the liquid discharge head. The ink discharged from the recovery port 13 is recovered into the ink tank.

[0065] If the distance between the nozzle surface of the liquid ejection head and the printed surface of the automobile U1 is about 20 cm, ink dots can be ejected onto the printed surface of the automobile U1 without problems.

[0066] The X-Y table 811 includes 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.

[0067] A liquid ejection unit 100 and a camera 812 (to be described later) are attached to a slider held by the Y-axis rail 813. Further, a shaft 815 is provided on the X-axis movement mechanism 814, and this shaft 815 is held by a robot arm 816. By this robot arm, the liquid ejection unit 100 can be freely arranged at a predetermined position where printing is to be performed with respect to the automobile U1.

[0068] For example, it can be arranged on the upper part of the automobile U1 as shown in Fig. 19(a) or at the lateral position of the automobile U1 as shown in Fig. 19(b) by the robot arm 816. Note that the operation of the robot arm 816 is controlled based on a program stored in advance in the control unit 600.

[0069] The camera 812 is disposed on a slider of the Y-axis rail 813 in the vicinity of the liquid ejection unit 100 and takes pictures of a predetermined range of the printed surface of the automobile U1 at a constant minute interval while moving in the X-Y direction. The camera 812 is a so-called digital camera, and as described above, specifications such as the lens specifications and resolution that enable taking a plurality of sub-divided images of a predetermined range of the printed surface are appropriately selected. The taking of a plurality of sub-divided images of the printed surface by the camera 812 is performed continuously and automatically according to a program provided in advance in the control unit 600.

[0070] The control unit 600 includes a storage device that records and stores various programs and data of photographed images, data of images to be printed, etc., and a central processing unit that executes various processes according to the programs. Further, the control unit 600 is composed of a so-called microcomputer equipped with an input device such as a keyboard and a mouse, and a DVD player etc. as required.

[0071] Also, the inkjet printer 810 further includes a monitor 610, and displays input information to the control unit 600, processing results by the control unit 600, etc. As will be described later, the control unit 600 performs image processing on a plurality of sub-divided image data photographed by the camera 812 using image processing software, and generates a composite print surface obtained by projecting the print surface of the non-planar automobile U1 onto a plane. Further, the control unit 600 edits the drawing target image as follows to generate an edited drawing target image. That is, the drawing target image, which is an image to be printed so as to be continuous with the already printed image on the print surface, is overlaid on the composite print surface, and the drawing target image is edited so as to be continuous with the edge of the printed image.

[0072] For example, for the drawing target image, an edited drawing target image is generated by editing (deforming) the drawing target image so as to be aligned with the composite print surface so that a non-printing area is not formed between adjacent drawing target images. Then, printing is actually performed by the liquid ejection unit 100 based on this edited drawing target image. As a result, it becomes possible to print a print image without a gap between the already printed print image. Note that the photographing of a plurality of sub-divided images by the camera 812 and the printing by ejecting ink from the nozzles of the respective liquid ejection heads of the liquid ejection unit 100 are performed by a drive unit 620 whose operation is controlled by the control unit 600.

[0073] FIG. 20 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 installed opposite the ejection target U2. The frame unit 840 includes a Y-axis rail 833 extending horizontally, a plurality of X-axis rails 834 extending vertically and provided at a predetermined interval, and a Z-axis rail 835 intersecting the X-axis rails 834 and the Y-axis rail 833.

[0074] Each X-axis rail 834 holds the Y-axis rail 833 so that the horizontally extending Y-axis rail 833 can move in the X direction (the nozzle array direction of the liquid ejection head, which is the vertical direction). Also, the Y-axis rail 833 holds the Z-axis rail 835 so that the Z-axis rail 835 can move in the Y direction. And the Z-axis rail 835 holds the carriage 831 so that the carriage 831 can move in the Z direction.

[0075] The carriage 831 includes 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. 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.

[0076] Further, it includes a first Z-direction driving unit 838 that moves the carriage 831 in the Z direction (which is the liquid ejection direction and the approach / separation direction with respect to the ejection target U2) along the Z-axis rail 835. Also, it includes a Y-direction driving unit 836 that moves the Z-axis rail 835 in the Y direction (which is a direction orthogonal to both the liquid ejection direction of the liquid ejection head and the nozzle array direction, and is a horizontal direction) along the Y-axis rail 833. Further, it includes an X-direction driving unit 837 that moves the Y-axis rail 833 in the X direction (which is the nozzle array direction of the liquid ejection head and is a vertical direction) along the X-axis rail 834. The Y-axis rail 833 is supported by the X-direction driving unit 837 held by each X-axis rail 834. Furthermore, it includes a second Z-direction driving unit 839 that moves the head holder 832 in the Z direction with respect to the carriage 831.

[0077] This inkjet printer 830 ejects paint from a liquid ejection head provided on the head holder 832 while moving the carriage 831 in the X-axis, Y-axis, and Z-axis directions, and performs drawing on the ejection target U2. Here, the movement of the carriage 831 and the head holder 832 in the Z direction does not necessarily 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 ejection head is a single row, the carriage 110 may hold the liquid ejection head so as to be tiltable with respect to the X direction, and the nozzle pitch may be made variable.

[0078] FIG. 21 is a schematic perspective view showing still another example of an inkjet printer as a device for ejecting liquid. The inkjet printer shown in FIG. 21 is, for example, an unmanned vehicle capable of traveling on a road surface, and can move on a road surface U3 such as a roadway or a sidewalk by driving wheels 871. Liquid (for example, paint) stored in a liquid tank 873 is supplied to a liquid ejection unit 872 having the liquid ejection head of the present embodiment through a cable 874. Paint is ejected from the liquid ejection unit 872 toward the road surface U3, and, for example, crosswalks, stop lines, center lines, etc. are formed on the painted portion P of the road surface U3.

[0079] Next, as another example of an apparatus for discharging a liquid including the liquid discharge head of the present embodiment, an electrode manufacturing apparatus will be described.

[0080] FIG. 22 is a schematic perspective view showing an example of an electrode manufacturing apparatus 850. The electrode manufacturing apparatus 850 shown in FIG. 22 is an apparatus for manufacturing a negative electrode used in an electrochemical element such as a primary battery, a secondary battery, a capacitor, or a condenser. The electrode manufacturing apparatus 850 includes a liquid discharge unit 852 having the liquid discharge head 10 of the present embodiment, and discharges a liquid onto a negative electrode substrate U4 on a stage 851 using an inkjet method.

[0081] The liquid tank 853 stores a liquid composition D1 for forming a negative electrode composite layer 855, and supplies the liquid composition D1 from the liquid tank 853 to the liquid discharge unit 852 via a tube 854.

[0082] FIG. 23 is a schematic perspective view showing another example of the electrode manufacturing apparatus 850. The electrode manufacturing apparatus 850 shown in FIG. 23 winds a strip-shaped negative electrode substrate U4 made of stainless steel, copper, or the like around a cylindrical core, and loads it onto a feed roller 857 and a take-up roller 859 with the surface for forming the negative electrode composite layer 855 facing upward. The feed roller 857 and the take-up roller 859 rotate counterclockwise, and the negative electrode substrate U4 moves in the direction from right to left in the figure.

[0083] The liquid tank 853 stores a liquid composition D1 for forming a negative electrode composite layer 855, and supplies the liquid composition D1 from the liquid tank 853 to the liquid discharge unit 852 via a tube 854. The liquid discharge unit 852 is installed above the negative electrode substrate U4 between the feed roller 857 and the take-up roller 859. Also, a plurality of liquid discharge units 852 may be installed in a direction substantially parallel or substantially perpendicular to the conveyance direction of the negative electrode substrate U4.

[0084] The delivery roller 857 and the winding roller 859 convey the negative electrode substrate U4 with the liquid composition D1 thereon to the drying device 858. As a result, the liquid composition D1 on the negative electrode substrate U4 is dried by the drying device 858 to become the negative electrode composite material layer 855, and a negative electrode 856 is formed in which the negative electrode composite material layer 855 is adhered to the negative electrode substrate as the negative electrode substrate. Thereafter, the negative electrode 856 is cut into a desired size by punching or the like.

[0085] The drying device 858 is not particularly limited as long as it does not directly contact the liquid composition D1, and can be appropriately selected. For example, a resistance heater, an infrared heater, a fan heater, etc. can be mentioned. Note that the drying device 858 may be configured to be installed on either the upper or lower side of the negative electrode substrate U4. Also, a plurality of drying devices 858 may be installed.

[0086] In the above, the device for manufacturing the negative electrode used in the electrochemical element has been described as an example, but it is of course possible to apply it to the device for manufacturing the positive electrode. When manufacturing the positive electrode, replace the negative electrode substrate with the positive electrode substrate, and replace the liquid composition D1 for forming the negative electrode composite material layer 855 with the liquid composition for forming the positive electrode composite material layer. Also, as the configuration other than the electrode composite material layer in the electrochemical element, there is no particular limitation, and known ones can be appropriately selected. For example, a positive electrode, a negative electrode, a separator, etc. can be mentioned.

[0087] Also, an external tank may be provided, and by controlling the valve, when the liquid composition D1 in the liquid tank 853 decreases, the liquid composition D1 may be supplied from the external tank 860 to the liquid tank 853.

[0088] As described above, the preferred embodiments of the present invention have been described. However, the present invention is not limited to such specific embodiments, and various modifications and changes are possible within the scope of the gist of the present invention described in the claims as long as it is not particularly limited in the above description.

[0089] In the above description, an embodiment has been described in which the piezoelectric element 18 opens and closes the needle valve 17. However, the present invention is not limited to this, and the needle valve 17 may be opened and closed by pneumatic or hydraulic pressure. In this case, the drive pulse generated by the drive control device 40 is a drive waveform for driving at a pressure set by a pressurizing mechanism using pneumatic or hydraulic pressure.

[0090] In the present application, the "device for discharging a liquid" includes a liquid discharge head or a liquid discharge unit in which functional components and mechanisms are integrated with the liquid discharge head, and is a device that 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 components or mechanisms are fixed to each other by fastening, adhesion, engagement, etc., and those in which one is held movably with respect to the other. Also, the liquid discharge head and the functional components or mechanisms may be detachable from each other.

[0091] 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.

[0092] Also, as the liquid discharge unit, there are those in which the liquid discharge head and the carriage are integrated, and those in which the liquid discharge head, the carriage, and the scanning movement mechanism are integrated. Also, as the liquid discharge unit, there is one in which the liquid discharge head is movably held by a guide member that constitutes a part of the scanning movement mechanism, and the liquid discharge head and the scanning movement mechanism are integrated.

[0093] As a liquid ejection unit, there is one in which a cap member that is a part of a maintenance and recovery mechanism is fixed to a carriage to which a liquid ejection head is attached, and the liquid ejection head, the carriage, and the maintenance and recovery mechanism are integrated. Also, as a liquid ejection unit, there is one in which a tube is connected to a liquid ejection head to which a head tank or a flow path component is attached, and the liquid ejection head and a supply mechanism are integrated. Through this tube, the liquid from a liquid storage source is supplied to the liquid ejection head.

[0094] The scanning movement mechanism shall include a single guide member. The supply mechanism shall include a single tube and a single loading unit.

[0095] 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.

[0096] 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 pretreatment devices, post-treatment devices, and the like.

[0097] For example, as a "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 a layer shape of powder in order to model a three-dimensional object (3D object).

[0098] Also, the "device for ejecting liquid" is not limited to those in which a significant image such as characters or figures is visualized by the ejected liquid. For example, those that form a pattern or the like that has no meaning by itself, and those that model a three-dimensional image are also included.

[0099] The above-mentioned "object to which liquid can adhere" refers to the object to which the liquid described above is to be ejected, 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, and media such as test cells, and include all objects to which liquid adheres unless otherwise particularly limited.

[0100] 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.

[0101] In addition, as for the "device for ejecting liquid", there is a device in which the head unit and the object to which liquid can adhere move relatively, but it is not limited thereto. Specific examples include a serial type device that moves the head unit and a line type device that does not move the head unit.

[0102] In addition, as the "device for ejecting liquid", there are also a treatment liquid coating device that ejects 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.

[0103] What has been described above is an example, and each of the following aspects has specific effects. (Aspect 1) A liquid ejection head 10 includes a valve member such as a needle valve 17 that opens and closes a nozzle 14 for ejecting a liquid, and an actuator such as a piezoelectric element 18. The liquid ejection head 10 further includes a movement mechanism 58 that moves the valve member between an open position where the nozzle 14 is opened and a closed position where the nozzle 14 is closed in accordance with displacement of the actuator. The movement mechanism 58 includes a leaf spring member 30 that is connected to the valve member and biases the valve member so that the valve member is positioned at the closed position. The leaf spring member 30 has an elastically deformable portion such as an inclined portion 32 that elastically deforms to generate a biasing force when the valve member is positioned at the closed position, and a connection portion with the valve member such as a valve connection portion 31 formed by being bent from the elastically deformable portion. The leaf spring member 30 further includes a reinforcing portion that reinforces the connection portion. When the valve member is pulled toward the actuator side by the leaf spring member to open the nozzle, a portion of the valve connection portion connected to the valve member that is not joined to the valve member may elastically deform. When the valve connection portion elastically deforms, after the valve connection portion elastically deforms to a certain extent, the movement of the valve member from the closed position to the open position is started, and there is a possibility that the responsiveness of the opening and closing of the valve member with respect to the displacement of the actuator deteriorates. On the other hand, in the present embodiment, by reinforcing the valve connection portion with the reinforcing portion, it is possible to suppress the elastic deformation of the valve connection portion when moving the valve member from the closed position to the open position. Thereby, the responsiveness of the opening and closing of the valve member with respect to the displacement of the actuator can be improved.

[0104] (Aspect 2) In aspect 1, the movement mechanism 58 has a pair of arm members 21 that rotate in conjunction with the displacement of an actuator such as the piezoelectric element 18. The leaf spring member 30 includes a first arm connection portion connected to one of the pair of arm members 21, a second arm connection portion connected to the other arm member, a first elastically deformable portion inclined with respect to the opening and closing direction of a valve member such as the needle valve 17 between the first arm connection portion and a connection portion such as the valve connection portion 31, and a second elastically deformable portion inclined with respect to the opening and closing direction between the second arm connection portion and the connection portion. According to this, as described in the embodiment, when the pair of arm members 21 rotate due to the displacement of an actuator such as the piezoelectric element 18, the valve member such as the needle valve 17 can be moved from the closed position to the open position via the leaf spring member 30. Further, when the valve member is positioned at the closed position, each elastic deformation portion that is inclined can be elastically deformed so as to bend, and the valve member can be biased toward the nozzle side. Thereby, the nozzle can be favorably sealed by the valve member, and leakage of the liquid from the nozzle can be suppressed.

[0105] (Aspect 3) In Aspect 1 or 2, the reinforcing portion is provided on at least one of the actuator side and the nozzle side with respect to the valve connection portion 31. According to this, compared with the case where there is no reinforcing portion, elastic deformation of the valve connection portion 31 is suppressed, and the responsiveness of the movement of the valve member with respect to the displacement of the actuator such as the piezoelectric element 18 can be improved.

[0106] (Aspect 4) In any one of Aspects 1 to 3, the reinforcing portion is provided on the actuator side and the nozzle side with respect to the valve connection portion 31, such as the piezoelectric element 18. According to this, compared with the case where the reinforcing portion is provided only on one side, elastic deformation of the valve connection portion 31 can be suppressed, and the responsiveness of the movement of the valve member with respect to the displacement of the actuator such as the piezoelectric element 18 can be further improved.

[0107] (Aspect 5) In Aspect 4, one of the reinforcing portion on the actuator side and the reinforcing portion on the nozzle side with respect to the valve connection portion 31 is a reinforcing member that is a separate member from the leaf spring member 30, and the other reinforcing portion is composed of an adhesive. According to this, as described with reference to FIG. 14, compared with the case where each of the reinforcing portion on the actuator side and the reinforcing portion on the nozzle side with respect to the valve connection portion 31 is configured by a reinforcing member that is a separate member from the leaf spring member 30, the number of parts can be reduced, and cost reduction of the device can be achieved.

[0108] (Aspect 6) In aspect 4, the reinforcing part on the actuator side with respect to the valve connection part 31 is a reinforcing member that is a separate member from the leaf spring member 30, and the reinforcing part on the nozzle side is formed on the valve member. According to this, as described with reference to FIG. 15, compared with the case where the reinforcing part on the nozzle side is a separate member, the number of assembly steps can be reduced, and an increase in manufacturing cost can be suppressed.

[0109] (Aspect 7) In aspect 4, the reinforcing part is a reinforcing member that is a separate member from the leaf spring member 30, and the reinforcing member has a slit part 51a into which the valve connection part 31 is fitted at the central part in the moving direction of the valve member such as the needle valve 17. According to this, as described in the embodiment, with one reinforcing member, the valve connection part 31 can be reinforced on both sides in the moving direction of the valve member. Thereby, compared with the case where each of the reinforcing part on the actuator side and the reinforcing part on the nozzle side with respect to the valve connection part 31 is configured by a reinforcing member that is a separate member from the leaf spring member 30, the number of parts can be reduced, and cost reduction of the device can be achieved.

[0110] (Aspect 8) In any one of aspects 1 to 7, the reinforcing part is a reinforcing member that is a separate member from the leaf spring member 30, and the reinforcing member is adhesively fixed to at least one of the valve member and the valve connection part 31. According to this, compared with the case of screwing the reinforcing member to a valve member such as a needle valve as described in the embodiment, the reinforcing member can be fixed with an inexpensive configuration.

[0111] (Aspect 9) In aspect 8, the reinforcing member is formed with a filling hole filled with an adhesive. According to this, as described in the embodiment, the amount of the adhesive can be quantified, and the adhesion range can be mechanically managed. Further, the valve connection part 31 can be reinforced with the adhesive filled in the filling hole.

[0112] (Aspect 10) In any one of Aspects 1 to 9, the reinforcing portion and the leaf spring member 30 are an integral body made of the same material. According to this, as described with reference to FIGS. 16 and 17, compared with the valve connection portion 31 having the same thickness as other portions of the leaf spring member 30 formed by bending the leaf spring member 30, the bending rigidity of the valve connection portion 31 can be increased. Thereby, elastic deformation of the valve connection portion 31 can be suppressed, and the responsiveness of the movement of the valve member such as the needle valve 17 with respect to the displacement of the actuator such as the piezoelectric element 18 can be improved.

[0113] (Aspect 11) In any one of Aspects 1 to 10, an assist biasing member such as an assist spring 23 for assisting the biasing of the valve member such as the needle valve 17 of the leaf spring member 30 is provided. According to this, as described with reference to FIG. 12, even if the biasing force due to the elastic deformation of the elastic deformation portion such as the inclined portion 32 of the leaf spring member 30 when the valve member such as the needle valve 17 is in the closed position is weak, it is possible to seal so that the liquid does not leak from the nozzle 14, and the elastic deformation of the elastic deformation portion can be suppressed. Thereby, the responsiveness of the valve member with respect to the displacement of the actuator when the actuator is displaced and the valve member is moved from the closed position to the open position via the leaf spring member 30 can be improved.

[0114] (Aspect 12) In an apparatus for discharging a liquid including the liquid discharge head 10, any one of the liquid discharge heads according to Aspects 1 to 9 is used as the liquid discharge head 10. According to this, even if the drive pulse applied to the actuator such as the piezoelectric element 18 is a high frequency, the valve member can be favorably reciprocated between the closed position and the open position, and the liquid can be favorably discharged.

Explanation of Reference Numerals

[0115] 10: Liquid discharge head 11: Housing 11a: Accommodating portion 12: Supply port 13: Recovery port 14: Nozzle 15: Nozzle plate 16: Flow path 17: Needle valve 18: Piezoelectric element 19: Piezoelectric element regulating member 20: Moving member 21: Arm member 21a: Support shaft 22: O-ring 23: Assist spring 29: Connector 30: Leaf spring member 31: Valve connection part 31a: Valve through-hole 32: Inclined part 33: Arm connection part 34: Reinforcing part 35: Adhesive 37: Reinforcing part 40: Drive control device 41: Waveform generation circuit 42: Amplification circuit 51: Reinforcing member 51a: Slit part 51b: Filling hole 52: Reinforcing member 52a: Filling hole 52b: Valve press-fitting hole 53: Reinforcing part 54: Reinforcing part 58: Moving mechanism 60: Head unit 62: Holder 63: Holder 70: Liquid ejection module 100: Liquid ejection unit 110: Carriage 600: Control unit 610: Monitor 620: Drive part 810: Inkjet printer 811: X-Y table 812: Camera 813: Y-axis rail 814: X-axis movement mechanism 815: Shaft 816: Robot arm 830: Inkjet printer 831: Carriage 832: Head holder 833: Y-axis rail 834: X-axis rail 835: Z-axis rail 836: Y-direction drive unit 837: X-direction drive unit 838: First Z-direction drive unit 839: Second Z-direction drive unit 840: Frame unit 850: Electrode manufacturing device 851: Stage 852: Liquid ejection unit 853: Liquid tank 854: Tube 855: Negative electrode composite layer 856: Negative electrode 857: Feeding roller 858: Drying device 859: Take-up roller 860: External tank 871: Wheel 872: Liquid ejection unit 873: Liquid tank 874: Cable

Prior art documents

Patent documents

[0116]

Patent Document 1

Claims

1. A valve member that opens and closes a nozzle for discharging a liquid, and a liquid discharge head having an actuator and a moving mechanism that moves the valve member between an open position where the nozzle is opened and a closed position where the nozzle is closed by displacement of the actuator. The moving mechanism includes a leaf spring member that is connected to the valve member and biases the valve member toward the nozzle side when the valve member is in the closed position. The leaf spring member has an elastically deformable portion that elastically deforms to generate a biasing force when the valve member is in the closed position, and a valve connection portion that is formed by being bent from the elastically deformable portion and is connected to the valve member. A liquid discharge head, characterized by comprising a reinforcing portion for reinforcing the valve connection portion.

2. In the liquid discharge head according to Claim 1, the moving mechanism has a pair of arm members that rotate in conjunction with displacement of the actuator, the leaf spring member has a first arm connection portion connected to one of the pair of arm members, a second arm connection portion connected to the other arm member, a first elastically deformable portion inclined with respect to the opening and closing direction of the valve member between the first arm connection portion and the valve connection portion, and a second elastically deformable portion inclined with respect to the opening and closing direction between the second arm connection portion and the valve connection portion. A liquid discharge head, characterized by having the same.

3. In the liquid discharge head according to Claim 1, the reinforcing portion is provided on at least one of the actuator side and the nozzle side with respect to the valve connection portion. A liquid discharge head, characterized by this.

4. In the liquid discharge head according to Claim 3, the reinforcing portion is provided on the actuator side and the nozzle side with respect to the valve connection portion. A liquid discharge head, characterized by this.

5. In the liquid discharge head according to Claim 4, one of the reinforcing portions on the actuator side and the nozzle side with respect to the valve connection portion is a reinforcing member that is a separate member from the leaf spring member, and the other reinforcing portion is made of resin. A liquid discharge head, characterized by this.

6. In the liquid discharge head according to Claim 4, the reinforcing portion on the actuator side with respect to the valve connection portion is a reinforcing member that is a separate member from the leaf spring member, and the reinforcing portion on the nozzle side is formed on the valve member. A liquid discharge head, characterized by this.

7. In the liquid discharge head according to Claim 4, The reinforcing portion is a reinforcing member that is a separate member from the leaf spring member, The liquid discharge head is characterized in that the reinforcing member has a slit portion into which the valve connection portion is fitted at a central portion in the moving direction of the valve member. **Claim 8** In the liquid discharge head according to claim 1, The reinforcing portion is a reinforcing member that is a separate member from the leaf spring member, The liquid discharge head is characterized in that the reinforcing member is adhesively fixed to at least one of the valve member and the valve connection portion. **Claim 9** In the liquid discharge head according to claim 8, The liquid discharge head is characterized in that a filling hole filled with an adhesive is formed in the reinforcing member. **Claim 10** In the liquid discharge head according to claim 1, The liquid discharge head is characterized in that the reinforcing portion and the leaf spring member are an integral body made of the same material. **Claim 11** In the liquid discharge head according to claim 1, The liquid discharge head is characterized in that an assist biasing member for assisting the biasing of the valve member of the leaf spring member is provided. **Claim 12** In an apparatus for discharging a liquid provided with a liquid discharge head, The apparatus for discharging a liquid is characterized in that the liquid discharge head according to claim 1 is used as the liquid discharge head.

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