JP2011062661A - Inkjet head and inkjet device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inkjet head and an inkjet device which can be miniaturized even if an operation part for jetting droplets of a coating solution through an orifice can be installed in a large number of installation parts as compared with that in a case of using a common PZT. <P>SOLUTION: The inkjet head 10 for discharging a coating solution in form of droplets is provided with an orifice 51, a pressurizing chamber 50 communicated with the orifice 51 and into which the coating solution 98 is introduced, a diaphragm 14 for transmitting pressure wave to the coating solution 98 in the pressurizing chamber 50 to discharge droplets L through the orifice by being vibrated, and an operation part 20 for vibrating the diaphragm 14. The operation part 20 comprises a container part 99 filled with a liquid 62, and a thermocouple terminal 61 for expanding and shrinking the liquid in the container part 99 to vibrate the diaphragm 14. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an inkjet head and an inkjet apparatus including the inkjet head, and more particularly to an inkjet head and an inkjet apparatus that apply a droplet of a coating liquid onto a workpiece.

  The structure of the ink-jet head is disclosed in Patent Document 1. The structure of the inkjet head disclosed in Patent Document 1 is shown in FIGS. 10 (A) and 10 (B). FIG. 10A is a plan view of the inkjet head, and FIG. 10B is a cross-sectional view of the inkjet head shown in FIG.

  The ink jet head shown in FIGS. 10A and 10B has a plurality of driving units 300, but there is a limit to downsizing the driving unit 300, so the orifices 301 are simply arranged in one row. Can not be placed. For this purpose, the driving units 300 are arranged in a staggered manner to realize a one-row arrangement of the orifices 301.

  The internal structure of the ink jet head will be further described. As shown in FIG. 10B, the coating liquid in the manifold 310 is supplied to the L-shaped channel 312 through the slit 311. The drive unit 300 propagates a pressure wave to the coating liquid. Specifically, vibration generated by the drive unit 300 that is PZT (lead zirconate titanate: piezo actuator) in the vertical direction (longitudinal direction) in FIG. It is transmitted to the coating liquid in the L-shaped channel 312. Further, the pressure wave of the coating liquid is transmitted to the orifice 301, and the coating liquid droplet 320 is discharged from the orifice 301.

  When droplets are ejected from the orifice 301, there is a problem that bubbles tend to remain on the surface of the diaphragm 313. In addition, there is a problem that air is left on the inner wall 315 of the L-shaped flow path 312 due to the outside air entering due to the reverse flow immediately after discharging the droplet. In the case of a coating solution containing a solid content, the solid content accumulates and aggregates at the bottom of the manifold 310 and enters the L-shaped flow path 312, causing clogging of the orifice 301.

JP 2006-321231 A

  By the way, when it is required to increase the number of drive units and the number of orifices in the inkjet head in order to increase the efficiency of applying droplets to the workpiece, as described above, PZT is used as the drive unit 300. Therefore, when the number of the drive units 300 is large, the ink jet head becomes large, the ink jet head cannot be miniaturized, and the ink jet apparatus having the ink jet head cannot be enlarged.

  The present invention has been made in view of the above, and an object of the present invention is to provide an inkjet head and an inkjet apparatus that can be miniaturized even if the number of drive units for discharging droplets of a coating liquid from an orifice is increased. Is to provide.

The inkjet head of the present invention is
An orifice for discharging the coating liquid in droplets;
A pressure chamber that leads to the orifice and into which the coating solution is introduced;
A diaphragm for transmitting a pressure wave generated by vibration to the coating liquid in the pressurizing chamber to discharge the liquid droplets from the orifice;
A drive unit for vibrating the diaphragm,
The drive unit is
A container portion for enclosing a liquid;
And a thermocouple terminal that oscillates the diaphragm by expanding and contracting the liquid in the container portion.

The inkjet device of the present invention is an inkjet device including an inkjet head that discharges a coating liquid in droplets, and the inkjet head includes:
An orifice for discharging the coating liquid in droplets;
A pressure chamber that communicates with the orifice and into which the coating liquid is introduced;
A diaphragm for transmitting a pressure wave generated by the vibration to the coating liquid in the pressurizing chamber and discharging the droplet from the orifice;
A drive unit that vibrates the diaphragm;
The drive unit is
A container portion for enclosing a liquid;
And a thermocouple terminal for expanding and contracting the liquid in the container portion to vibrate the diaphragm.

  According to the present invention, it is possible to provide an ink jet head and an ink jet apparatus that can be reduced in size even when the number of drive units for discharging droplets of a coating liquid from an orifice is increased.

In an embodiment of the present invention, it is a perspective view showing an ink jet device provided with an ink jet head. 1 is a perspective view showing an ink jet head used in an ink jet apparatus in an embodiment of the present invention. It is sectional drawing in the AA line which shows the internal structure of the inkjet head shown in FIG. It is a figure which expands and shows the drive part and pressurization chamber vicinity. It is a figure which shows a drive part and pressurization chamber vicinity. It is a top view of an inkjet head. It is sectional drawing in the BB line of the inkjet head shown in FIG. It is a figure which shows the assembly procedure of an inkjet head. It is a figure which shows a mode that water is inject | poured in a drive part. It is a figure which shows the prior art example of an inkjet head.

  Embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view showing an embodiment of an ink jet apparatus including the ink jet head of the present invention.

  An inkjet apparatus 200 shown in FIG. 1 is an apparatus that applies a coating liquid as droplets onto the surface of a workpiece W. The workpiece W is, for example, a glass substrate or a semiconductor wafer for a liquid crystal display device, but is not particularly limited.

  The ink jet apparatus 200 includes an ink jet head unit 201 and a work holding unit 202. In the inkjet head unit 201, for example, a plurality of inkjet heads 10 are arranged along the X direction. The inkjet head unit 201 can be positioned by moving up and down in the Z direction by rotating the feed screw 251 by the operation of the motor M1. Each inkjet head 10 of the inkjet head unit 201 is connected to the coating liquid supply unit 203, and the coating liquid in the coating liquid supply unit 203 can be supplied to the inlet of each inkjet head 10. The coating liquid is a liquid for forming droplets.

  The work holding unit 202 illustrated in FIG. 1 includes a first moving unit 211, a second moving unit 212, and a base 213. The first moving unit 211 is disposed on the second moving unit 212, and the second moving unit 212 is disposed on the base 213. The workpiece W is detachably fixed to the upper surface of the first moving unit 211, for example, by suction.

  The output shaft of the motor M2 is connected to the feed screw 252. The feed screw 252 is engaged with a nut 272 fixed to the first moving unit 211 side. Similarly, the output shaft of the motor M3 is connected to the feed screw 253, and the feed screw 253 is engaged with a nut 273 fixed to the second moving portion 212 side.

  The first moving portion 211 can be positioned by moving in the X direction along the guide rail 262 by rotating the feed screw 252 by the operation of the motor M2. The second moving unit 212 can be positioned by moving in the Y direction along the guide rail 263 by rotating the feed screw 253 by the operation of the motor M3. The X, Y, and Z directions are orthogonal.

  The operations of the motors M1, M2, and M3 are controlled by commands from the control unit 280. Further, the operation of the coating liquid supply unit 203 to send the liquid to each inkjet head 10 is controlled by a command from the control unit 280.

  In the inkjet apparatus 200 shown in FIG. 1, the nozzle surfaces of the inkjet heads 10 of the inkjet head unit 201 are positioned in the Z direction by operating the motor M <b> 1 so as to be at a predetermined interval with respect to the workpiece W. The first moving unit 211 is moved in the X direction by operating the motor M2, and is moved in the Y direction together with the second moving unit 212 by operating the motor M3. Thereby, since the inkjet head unit 201 moves relative to the workpiece W in the X direction, the Y direction, and the Z direction, the workpiece W has an orifice on the nozzle surface of each inkjet head 10 of the inkjet head unit 201. The coating liquid can be selectively discharged and applied.

  FIG. 2 is a perspective view showing an embodiment of an inkjet head used in the inkjet apparatus of the present invention shown in FIG. FIG. 3 is a cross-sectional view taken along line AA showing the internal structure of the inkjet head shown in FIG.

  2 and 3 constitutes an inkjet head unit 201 shown in FIG. 1 by arranging a plurality of inkjet heads 10. The ink jet head 10 includes a packing pressing plate 11, a packing 12, a drive unit constituting plate 13, a diaphragm 14, a chamber plate 16, an orifice plate 17, and a drive unit 20.

  As shown in FIG. 3, the packing pressing plate 11 and the drive unit constituting plate 13 are flat members. The packing pressing plate 11 is disposed on the driving unit constituting plate 13, and the packing 12 is sandwiched between the packing pressing plate 11 and the driving unit constituting plate 13.

  As shown in FIG. 3, the drive unit constituting plate 13, the diaphragm 14, the chamber plate 16 and the orifice plate 17 are laminated.

  As shown in FIGS. 2 and 3, the drive unit 20 is provided at the center position of the laminate of the packing pressing plate 11, the packing 12, and the drive unit constituting plate 13. The nozzle unit 30 includes a chamber plate 16 and an orifice plate 17. A plurality of nozzle units 30 are arranged at intervals along the X direction shown in FIGS. 2 and 3. Therefore, the orifices 51 formed on the nozzle surface N are formed at a predetermined pitch along the X direction. As shown in FIG. 3, the driving unit 20 is provided corresponding to the position of the upper portion of each nozzle unit 30.

  As shown in FIG. 3, a coating liquid introduction port 40, a manifold 41, and a slit 42 are formed between the packing 12 and the drive unit constituting plate 13. Further, between the packing 12 and the drive unit constituting plate 13, passages 49, 44, 45, a manifold 46 for introducing the coating liquid, and a purge outlet 47 are formed. Further, passages 48 and 49 and a pressurizing chamber 50 are formed between the diaphragm 14 and the chamber plate 16. An orifice 51 is formed in the orifice plate 17.

  As shown in FIG. 3, the inlet 40 and the manifold 41 for introducing the coating liquid are formed between the packing 12 and the drive unit constituting plate 13 along the Y direction. The slit 42 has a passage 42 </ b> A and passages 43 and 48. The passage 42 </ b> A is formed along the Y direction between the packing 12 and the drive unit constituting plate 13. The passage 43 is formed in the Z direction across the drive unit constituting plate 13, the diaphragm 14, and the chamber plate 16. The passage 48 connects the passage 43 and the pressurizing chamber 50 and is formed in the Y direction.

  Moreover, the manifold 41 is formed long in the X direction as shown in FIG. As shown in FIG. 3, the introduction port 40, the manifold 41, and the slit 42 are connected in order. A first end of the manifold 41 is connected to the introduction port 40, and a second end of the manifold 41 is connected to the slit 42. The manifold 41 has a curved bottom surface portion 52.

  On the other hand, as shown in FIG. 3, the passages 49 and 45, the manifold 46, and the discharge port 47 are formed along the Y direction, and the passage 44 is formed along the Z direction. The manifold 46 is formed long in the X direction as shown in FIG. The passages 44 and 45, the manifold 46, and the discharge port 47 are connected in order to form a bubble vent channel 59 described later. A first end of the manifold 46 is connected to the slit 45, and a second end of the manifold 41 is connected to the discharge port 47. The manifold 46 has a curved bottom surface portion 53.

  As shown in FIG. 3, the passage 48 of the slit 42 is connected to the upper end portion 50 </ b> A of the pressurizing chamber 50 of the nozzle unit 30. The pressurizing chamber 50 of the nozzle unit 30 is positioned below the driving unit 20, and the lower end 50 </ b> B of the pressurizing chamber 50 is connected to the orifice 51. The orifice 51 is formed in the orifice plate 17.

  In FIG. 3, the coating liquid is introduced from the introduction port 40, moves to the pressurizing chamber 50 through the passages 42 </ b> A, 43, 48 of the manifold 41 and the slit 42, and is discharged as droplets L from the orifice 51. it can. The passages 42 </ b> A, 43, 48 of the slit 42 are formed to be narrower than the introduction port 40 and the manifold 41. As a result, the coating liquid introduced from the introduction port 40 can pass through the slits 42 to make the liquid supply pressure to each nozzle unit 30 uniform, and at the same time, in the pressure chamber 50 of each nozzle unit 30. Can prevent trash from entering.

  Further, as shown in FIG. 3, the piezoelectric vibrator 60 is disposed in the drive unit constituting plate 13 below the manifold 41 on the coating liquid introduction side. The piezoelectric vibrator 60 is provided so as to be long in the X direction so as to correspond to the manifold 41 as shown in FIG. As a result, the piezoelectric vibrator 60 vibrates the manifold 41, thereby preventing the solid content of the coating liquid from being deposited on the bottom surface portion 52 of the manifold 41. Accordingly, it is possible to eliminate the inconvenience that the coating liquid does not pass and the droplet L cannot be discharged.

  The pressure wave generated when the diaphragm vibration surface 14D of the diaphragm 14 of the drive unit 20 shown in FIG. 3 is vibrated is propagated to the orifice 51, so that the coating liquid in the pressure chamber 50 is transferred from the pressure chamber 50 to the nozzle surface N. It can be discharged as a droplet L through the orifice 51.

  If bubbles enter the pressure chamber 50, the bubbles are likely to adhere to the diaphragm vibration surface 14D of the diaphragm 14. In order to remove the adhering bubbles from the diaphragm vibrating surface 14D, an air bubble removal channel 59 for removing air bubbles is provided on the opposite side of the introduction port 40. The bubble removal flow path 59 includes passages 49, 44, 45, a manifold 46 and a discharge port 47. The passages 49, 44, 45 are formed narrower than the manifold 46 and the discharge port 47.

  As a result, when the purge outlet 47 is set to a negative pressure, a flow parallel to the diaphragm vibration surface 14D of the diaphragm 14 is created from the inlet 40 toward the purge outlet 47 on the opposite side. Air bubbles adhering to the surface 14 </ b> D can be reliably extracted to the outside from the discharge port 47 through the air bubble removal channel 59. Accordingly, it is possible to eliminate the inconvenience that the coating liquid does not pass and the droplet L cannot be discharged. When introducing the coating liquid into the inkjet head 10, it is possible to prevent bubbles and dust from entering the inkjet head 10, and it is possible to prevent bubbles from entering the inkjet head 10 when discharging the coating liquid.

  Next, a structural example of the drive unit 20 will be described.

  4 is an enlarged view showing the vicinity of the drive unit 20 and the pressurizing chamber 50 shown in FIG. FIG. 5 shows an example of dimensions of the drive unit 20.

  Conventionally, in order to increase the efficiency of applying droplets to a workpiece, when it is required to increase the number of arrangements of drive units and orifices in an inkjet head, PZT is used as the drive unit as described above. Therefore, if the number of drive units is large, the ink jet head becomes large, the ink jet head cannot be miniaturized, and the ink jet apparatus having the ink jet head cannot be enlarged.

  Therefore, in the embodiment of the present invention, in order to reduce the size of the drive unit, PZT is not used, but a thermocouple terminal 61 having a thickness smaller than that of PZT is used. As shown in FIGS. 3 and 4, the drive unit 20 includes a thermocouple terminal 61, a liquid 62, and a container unit 99 as a measure for preventing the inkjet head 10 from becoming large.

  As shown in FIG. 4, in the inkjet head 10 that discharges the coating liquid as droplets, the pressurizing chamber 50 communicates with the orifice 51, and the coating liquid 98 is introduced into the pressurizing chamber 50. The diaphragm vibrating surface 14 </ b> D of the diaphragm 14 transmits a pressure wave generated by the vibration to the coating liquid 98 in the pressurizing chamber 50 and discharges the droplet L from the orifice 51. The drive unit 20 that vibrates the diaphragm vibration surface 14D of the diaphragm 14 is a thermoelectric that vibrates the diaphragm vibration surface 14D of the diaphragm 14 by expanding and contracting the container part 99 that encloses the liquid 62 and the liquid 62 in the container part 99. A counter terminal 61 is provided.

  The container part 99 of the drive part 20 shown in FIG. 4 has the main body container 20M and the cover part 20N. The upper part of the main body container 20M is closed by a lid 20N, and a thermocouple terminal 61 is attached to the lid 20N. A projection 64 is provided inside the main body container 20M so as to face each other. The lower opening 20T of the main body container 20M is closed by a diaphragm vibration surface 214D of the diaphragm 14. The main body container 20M is filled with a liquid 62.

  As shown in FIG. 3, the temperature controller 63 is electrically connected to the thermocouple terminal 61, and controls the temperature of the thermocouple terminal 61 by applying an applied voltage to the thermocouple terminal 61. Thus, the thermocouple terminal 61 changes the liquid temperature of the liquid 62 in the container part 99.

  Thereby, the diaphragm 62 of the diaphragm 14 is vibrated by expanding and contracting the liquid 62 in the container part 99. In addition, although the kind of this liquid 62 is arbitrary, water can be used, for example. When water is used as the liquid 62 in this way, if the liquid 62 is heated by the thermocouple terminal 61, the liquid 62 is heated and expanded toward the diaphragm vibrating surface 14D. The pressure wave can be propagated by pushing the coating liquid in 50.

  Conversely, if the thermocouple terminal 61 is cooled to 0 ° C. or lower, the liquid 62 will coagulate and expand toward the diaphragm vibrating surface 14D, so that the diaphragm vibrating surface 14D pushes the coating liquid in the pressurizing chamber 50. Pressure waves can be propagated. At this time, a protrusion 64 is provided in the drive unit 20 so that the solidified substance does not move and contact the thermocouple terminal 61 in the drive unit 20.

  The driving unit 20 shown in FIGS. 4 and 5 uses a thermocouple terminal 61. Instead of expanding and contracting the PZT, the thermocouple terminal 61 vibrates the diaphragm 14 using the Peltier effect. Specifically, the temperature of the liquid 62 in the container 99 of the drive unit 20 is changed by the temperature change of the thermocouple terminal 61, and the liquid 62 is expanded and contracted. The diaphragm vibration surface 14D of the diaphragm 14 is vibrated by the pressure fluctuation of the liquid 62 generated when the liquid 62 expands and contracts.

  The arrangement pitch of the flow path of the coating liquid leading to the normal orifice is, for example, 1000 μm (1 mm) when driven using normal PZT expansion / contraction, but in order to reduce the size of the inkjet head 10, In the embodiment, the arrangement pitch of the flow paths of the slits 42 needs to be suppressed to about 50% (0.5 mm) of 1000 μm. As shown in FIG. 5, the thickness of the thermocouple terminal 61 is a minimum of 0.25 mm, and the drive units 20 can be arranged in a line at a pitch of 0.5 mm.

In the embodiment of the present invention, the displacement caused by the vibration of the diaphragm vibrating surface 14D of the diaphragm 14 shown in FIG. 4 is the discharge amount of the coating liquid 98 when the coating liquid 98 is discharged as the droplet L from the orifice 51. But,
10PL (picoliter) + back flow rate of coating liquid to the inlet side 10PL = 20PL
It is necessary to generate a volume change.

This volume change is equivalent to a volume change caused by a displacement caused by driving a PZT that is normally used. Since the flow path of the slit 42 is narrow and extremely short, and the introduction port 40 is narrowed, the reverse flow rate of the coating liquid to the introduction port at the time of discharge is considered to be about 10 PL. The amount of displacement of this coating solution is
20PL = 2e-8cc = volume (π × 0.025 ² /4)×0.05×expansion coefficient 0.207e-3 × temperature change Δ (delta) T. From this, if the temperature change Δ (delta) T = 4 ° C. is changed, 10 PL of coating liquid can be discharged.

In the embodiment of the present invention, the expansion / contraction time of the diaphragm vibrating surface 14D of the diaphragm 14 can be realized at 1 μs / 20 PL when contracted and 0.1 μs / 20 PL or more when expanded, which is equivalent to PZT that is usually used. There is a need to. Also in the thermocouple terminal 61, the thermocouple terminal 61 may be heated at 4 ° C./μs in order to realize a discharge amount of 20 PL / μs equivalent to PZT. The energy required for expansion at this time is
Specific heat 1 × mass (π × 0.025 ² /4)×0.05×4° C. × 4.19 (J) = 4.11 × 10 ⁻⁴ J
Here, in order for the thermocouple terminal 61 to realize a contraction time of 1 μs / 20PL similar to PZT, the above equation is divided by 1 μs and power 411 W is required. Moreover, in order for the thermocouple terminal 61 to realize an expansion time of 0.1 μs / 20PL similar to PZT, power 4110 W is required. Note that if ethanol is used instead of water as the liquid 62 in FIG. 4, an electric power of 2370 W is sufficient to realize an expansion time of 0.1 μs / 20 PL similar to PZT.

  By using water as the liquid 62, the thermal conductivity of water is 1.4 kcal / (m · s · ° C.), that is, 1.4 × 4190 = 5866 J / (s · m · k). The thermal conductivity of SUS of the surrounding material is 16.3 J / (s · m · k). Accordingly, since the thermal conductivity of water is 360 times that of SUS and the thermal conductivity of water is dominant, the heat of the liquid 62 escapes from the surrounding SUS-made parts during driving of the driving unit 20. There is no fear of going.

  As shown in FIG. 2, the plurality of driving units 20, the pressurizing chambers 50, and the orifices 51 are arranged at intervals in series along the X direction. That is, the drive unit 20 and the orifices 51 can be arranged in a row without arranging the plurality of drive units 20, the pressurizing chambers 50, and the orifices 51 in a staggered manner. A plurality of drive units 20, pressurizing chambers 50, and orifices 51 are provided with a manifold 41 on the application liquid introduction side and a purge manifold 46 in parallel. Thereby, the enlargement of an inkjet head can be avoided.

(Other embodiments)
Next, another embodiment of the ink jet head of the present invention will be described with reference to FIGS.

  6 is a plan view of the inkjet head 10A, and FIG. 7 is a cross-sectional view taken along the line BB of the inkjet head 10A shown in FIG. FIG. 8 is a diagram illustrating an assembly procedure of the inkjet head 10A. FIG. 9 is a diagram illustrating a state in which water is injected into the drive unit 120.

  As shown in FIG. 8A, the drive unit constituting plate 113 and the diaphragm 114 are bonded together with an epoxy adhesive 170. As shown in the enlarged view of FIG. 8B, the thermocouple terminal 161 is inserted until it hits the diaphragm 114 through the insertion hole 113H of the driving unit constituting plate 113 in order to suppress variations among the driving units 120. Has been. If there is a gap between the thermocouple terminal 161 and the insertion hole 113H of the drive unit constituting plate 113, liquid or air accumulates in the gap, causing a drive error.

  Therefore, it is necessary to reduce the influence as much as possible so that the space between the thermocouple terminal 161 and the insertion hole 113H of the drive unit constituting plate 113 is not formed so as not to be a reservoir for liquid or air. For this reason, a counterbore 172 having a concave cross section is provided as shown in FIG. After the thermocouple terminal 161 is inserted into the insertion hole 113H, the concave portion of the spot facing 172 is filled with an epoxy-based adhesive 173. ing.

  As shown in FIGS. 7 and 8D, the drive unit 120 includes a thermocouple terminal 161, a liquid 62, and a container unit 199.

  As shown in FIG. 7, in the inkjet head 10 </ b> A that discharges the coating liquid as droplets, the pressurizing chamber 150 communicates with the orifice 151, and the coating liquid 98 is introduced into the pressurizing chamber 150. The diaphragm vibrating surface 114 </ b> D of the diaphragm 114 transmits a pressure wave generated by the vibration to the coating liquid 98 in the pressurizing chamber 150 and discharges the droplet L from the orifice 151. The drive unit 120 that vibrates the diaphragm vibration surface 114D of the diaphragm 114 is a thermoelectric that vibrates the diaphragm vibration surface 114D of the diaphragm 114 by expanding and contracting the container part 199 that encloses the liquid 62 and the liquid 62 in the container part 199. A counter terminal 161 is provided.

  The container part 199 shown in FIG. 7 is formed in the drive part structure board 113, and the liquid 62 is accommodated in the container part 199. The liquid 62 is, for example, water, but this water is injected into the container part 199 at the stage shown in FIG. The method for injecting the liquid 62 is as follows.

  As shown in FIG. 9A, water 175 as the liquid 62 is accommodated in the container 174, and the drive unit 120 is submerged in the water 175. A suction jig 177 is connected to the injection port 176 of the drive unit 120, and the air in the container portion 199 of the drive unit 120 is sucked from the suction jig 177 through the injection port 176 to make a vacuum.

  Thereafter, the suction jig 177 is removed from the inlet 176 in the water 175, and the container 199 is filled with the water 175 through the inlet 176. The inlet 176 is sealed by pressing the packing 112 in water. As shown in FIG. 8C, the packing 112 is fixed to the drive unit constituting plate 113 with a packing pressing plate 111 and screws 178.

  Next, as shown in FIG. 8D, the chamber plate 116 and the orifice plate 117 are both made of SUS and integrated by diffusion bonding. On this chamber plate 116, a SUS reductor 115 is placed.

  As shown in FIG. 8D, the driving unit 120 is fixed on the assembly unit of the restrictor 115, the chamber plate 116, and the orifice plate 117 constituting the flow path portion of the coating liquid by screws 179. . A slit 142 is formed in the restrictor 115. The slit 142 is formed in the lower part of the driving unit 120.

  As shown in FIG. 8D, the chamber plate 116 is formed with a manifold 141 and a manifold 146. A pressurizing chamber (also referred to as a chamber) 150 is formed between the manifold 141 and the manifold 146 of the chamber plate 116. The manifold 141 and the manifold 146 are connected to the pressurizing chamber 150 through the slit 142. The pressurizing chamber 150 is at a position corresponding to the diaphragm vibrating surface 114D of the diaphragm 114.

  As shown in FIG. 7, the piezoelectric vibrator 60 is disposed in the chamber plate 116 below the manifold 141. The piezoelectric vibrator 60 is provided in the X direction so as to correspond to the manifold 141. As a result, the piezoelectric vibrator 60 vibrates the lower portion of the manifold 141, thereby preventing the solid content of the coating liquid from being deposited on the bottom surface portion 152 of the manifold 141.

  The inkjet head 10A configured as described above can be used in the inkjet head unit 201 shown in FIG.

  In the inkjet head 10 </ b> A shown in FIG. 7, the coating liquid 98 is introduced from the inlet 140, moves in the order of the pressurizing chamber 150 of the nozzle unit 130 through the manifold 141 and the slit 142, and drops from the orifice 151. Can be discharged.

  The slit 142 is formed to be narrower than the manifold 141. As a result, the liquid supply pressure of the introduced coating liquid 98 to each nozzle unit 130 can be made uniform, and dust can be prevented from entering the nozzle units 130. The coating liquid 98 can be discharged as a droplet L from the pressure chamber 150 through the orifice 151 by propagating a pressure wave generated when the diaphragm vibrating surface 114 </ b> D of the diaphragm 114 of the driving unit 120 is vibrated to the orifice 151. .

  If air bubbles enter the pressure chamber 150, there is a high possibility of adhering to the diaphragm vibration surface 114D of the diaphragm 114. In order to remove the attached bubbles, an air bubble removal channel 159 for removing air bubbles is formed on the side opposite to the introduction port 140. The bubble removal channel 159 has a slit 142, a manifold 146, and a discharge port 147.

  Accordingly, by making the purge outlet 147 have a negative pressure, a flow parallel to the diaphragm vibrating surface 114D of the diaphragm 114 is created from the inlet port 140 toward the purge outlet 147, thereby generating a diaphragm vibrating surface. Bubbles attached to 114D can be removed. In this way, when introducing the coating liquid into the inkjet head 10A, it is possible to prevent bubbles and dust from entering the inkjet head 10A, and to prevent bubbles from entering the inkjet head 10A when discharging the coating liquid. Can be prevented.

  As shown in FIG. 7, as a measure for avoiding the increase in size of the inkjet head 10 </ b> A, the drive unit 120 is smaller than the PZT as described above without using PZT for the drive unit 120. The thermocouple terminal 161, the liquid 62, and the container part 199 are comprised. As shown in FIG. 7, the temperature controller 163 is electrically connected to the thermocouple terminal 161, and controls the temperature of the thermocouple terminal 161 by applying an applied voltage to the thermocouple terminal 161. As a result, the thermocouple terminal 161 changes the liquid temperature of the liquid 62. As a result, the liquid 62 is expanded and contracted to vibrate the diaphragm vibration surface 114D of the diaphragm 114.

  In addition, although the kind of this liquid 162 is arbitrary, water can be used, for example. When water is used as the liquid 62, if the liquid 162 is heated by the thermocouple terminal 161, the liquid 62 is heated and expanded toward the diaphragm vibration surface 114D, so that the diaphragm vibration surface 114D is applied in the pressurizing chamber 150. The pressure wave can be propagated by pushing the liquid 98.

  Conversely, if the thermocouple terminal 161 is set to 0 ° C. or lower, the liquid 62 is solidified and expanded toward the diaphragm vibrating surface 114D, and therefore the diaphragm vibrating surface 114D pushes the coating liquid 98 in the pressurizing chamber 150. Pressure waves can be propagated.

  In an embodiment of the present invention, an ink jet head and an ink jet device including the ink jet head can be reduced in size even when the number of drive units for discharging droplets of the coating liquid from the orifice is increased. When air bubbles are introduced, air bubbles are prevented from entering, and even if air bubbles enter, they can be removed, and the solid content can hardly be deposited on the bottom of the manifold.

  In addition, this invention is not limited to the said embodiment.

  For example, the configuration of the inkjet apparatus shown in FIG. 1 is an example, and the moving direction of the inkjet head unit and the moving direction of the workpiece W are not particularly limited.

  Furthermore, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiments of the present invention. For example, you may delete some components from all the components shown by embodiment of this invention. Furthermore, you may combine the component covering different embodiment suitably.

10, 10A inkjet head, 11 packing pressing plate, 12 packing, 13 driving part constituting plate, 14 diaphragm, 14D diaphragm vibrating surface, 16 chamber plate, 20, 120 driving part, 30 nozzle unit, 40 inlet for coating liquid, 41 Manifold, 42 Slit, 44, 45, 49 Passage, 46 Manifold, 47 Discharge port, 50 Pressurization chamber, 51 Orifice, 59 Bubble vent channel, 60 Piezoelectric vibrator, 61 Thermocouple terminal of drive unit, 62 Drive unit Liquid, 99 drive unit container, 200 inkjet device, 201 inkjet head unit, 202 work holding unit, 211 first moving unit, 212 second moving unit, 213 base, 280 control unit, W work, L droplet

Claims (5)

An orifice for discharging the coating liquid in droplets;
A pressure chamber that communicates with the orifice and into which the coating liquid is introduced;
A diaphragm for transmitting a pressure wave generated by the vibration to the coating liquid in the pressurizing chamber and discharging the droplet from the orifice;
A drive unit that vibrates the diaphragm,
The drive unit is
A container portion for enclosing a liquid;
An ink jet head comprising: a thermocouple terminal for expanding and contracting the liquid in the container portion to vibrate the diaphragm. An inlet that introduces the coating liquid into the pressurizing chamber, a manifold that is connected to the inlet and introduces the coating liquid, and a slit that connects the manifold and the pressurizing chamber;
The inkjet head according to claim 1, wherein the slit is formed narrower than the manifold.   The inkjet head according to claim 1, further comprising a piezoelectric vibrator that vibrates the manifold.   The inkjet head according to claim 3, wherein the pressurizing chamber has a bubble vent channel for discharging bubbles of the coating liquid generated in the pressurizing chamber to the outside. An inkjet apparatus including an inkjet head that discharges a coating liquid in droplets,
The inkjet head is
An orifice for discharging the coating liquid in droplets;
A pressure chamber that communicates with the orifice and into which the coating liquid is introduced;
A diaphragm for transmitting a pressure wave generated by the vibration to the coating liquid in the pressurizing chamber and discharging the droplet from the orifice;
A drive unit that vibrates the diaphragm;
The drive unit is
A container portion for enclosing a liquid;
An ink jet apparatus comprising: a thermocouple terminal that expands and contracts the liquid in the container portion to vibrate the diaphragm.

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