JP7039866B2 - Manufacturing method of liquid discharge device and liquid discharge device - Google Patents

Description

The present invention relates to a liquid discharge device and a method for manufacturing a liquid discharge device.

An actuator such as a piezoelectric element (piezo element) displaces the vibrating plate attached to the liquid chamber, and the liquid such as ink contained in the liquid chamber is discharged from a nozzle communicating with the liquid chamber. A discharge device is known (for example, Patent Document 1 below).

Japanese Unexamined Patent Publication No. 7-290702

In the above-mentioned technique of Patent Document 1, the elastic member is compressed by the elongation of the piezoelectric element, and the liquid is discharged from the nozzle by displaced the diaphragm, and the diaphragm is flexed and deformed by the expansion and contraction of the piezoelectric element. However, the energy loss due to the liquid discharge is suppressed. However, in the technique of Patent Document 1, the diaphragm and the piezoelectric element are bonded by an adhesive (paragraph 0016 of Patent Document 1). Therefore, there is a problem that the adhesive material is peeled off, the diaphragm cannot follow the shrinkage of the piezoelectric element, and the liquid ejection accuracy is lowered. Further, in the liquid discharge device, depending on the liquid discharge characteristics, the liquid discharge accuracy may change depending on the driving conditions thereof. As described above, in the liquid discharge device, there is still room for improvement in the liquid discharge accuracy.

The present invention has been made to solve at least a part of the above-mentioned problems, and can be realized as the following forms.
It is a liquid discharge device
A head main body having a liquid chamber for accommodating a liquid and a nozzle for discharging the liquid in the liquid chamber.
The diaphragm that forms part of the wall of the liquid chamber,
An elastic member arranged between the diaphragm and the head body and supporting the diaphragm, and
A drive unit connected to the diaphragm, elastically deforming the elastic member to displace the diaphragm, and applying an external force to discharge the liquid from the nozzle to the diaphragm.
A fastening portion for fastening the drive portion, the diaphragm, and the head main body portion so as to support the diaphragm in a compressed state of the elastic member.
Equipped with
A liquid discharge device having a spacer between the diaphragm and the head body portion that limits compression of the elastic member.

[1] One embodiment of the present invention is provided as a liquid discharge device. The liquid discharge device of this form includes a head main body having a liquid chamber for accommodating the liquid and a nozzle for discharging the liquid in the liquid chamber; and a vibrating plate forming a part of a wall portion of the liquid chamber. An elastic member arranged between the vibrating plate and the head body and supporting the vibrating plate; connected to the vibrating plate, the elastic member is elastically deformed to displace the vibrating plate, and the nozzle A drive unit that applies an external force to discharge the liquid from the vibrating plate; the drive unit, the vibrating plate, and the head main body portion so as to support the vibrating plate in a compressed state of the elastic member. And a fastening portion for fastening;
According to this form of the liquid discharge device, the drive portion, the diaphragm, and the head main body portion are fastened with the elastic member compressed by the fastening portion, so that the drive portion and the diaphragm are separated from each other. It is suppressed that the diaphragm does not follow the drive of the drive unit. Therefore, it is possible to prevent the liquid discharge accuracy from being lowered due to the deterioration of the followability of the diaphragm with respect to the drive unit.

[2] In the liquid discharge device of the above embodiment, the amount of compression of the elastic member by the fastening portion may be adjusted according to the driving conditions of the driving portion.
According to this form of the liquid discharge device, the compression amount of the elastic member can be adjusted to change the liquid discharge characteristics so as to meet the drive conditions of the drive unit. Therefore, it is possible to suppress the occurrence of variation in the discharge accuracy of the liquid due to the difference in the driving conditions of the driving unit.

[3] In the liquid discharge device of the above embodiment, the fastening portion may have an adjusting portion for adjusting the compression amount of the elastic member.
According to this form of the liquid discharge device, the compression amount of the elastic member can be adjusted by the adjusting unit, so that the liquid discharge characteristics can be easily adjusted. Therefore, it is easy to control the discharge accuracy of the liquid.

[4] The liquid discharge device of the above embodiment may have a spacer between the diaphragm and the head main body to limit the compression of the elastic member.
According to this form of the liquid discharge device, it is possible to prevent the elastic member from being excessively compressed and deteriorated, and the elastic force thereof being lowered. Therefore, it is possible to prevent the liquid discharge accuracy from being lowered due to the deterioration of the elastic member.

[5] In the liquid discharge device of the above embodiment, the head main body portion surrounds the liquid chamber below the diaphragm, is inclined downward toward the liquid chamber, and has an inclined wall surface facing the diaphragm. The elastic member may be arranged so as to be sandwiched between the inclined wall surface and the diaphragm.
According to this form of the liquid discharge device, when the diaphragm is displaced by the drive unit, the elastic member is suppressed from being deformed so as to expand toward the outside of the liquid chamber by the inclined wall surface. Therefore, it is possible to prevent the energy for discharging the liquid from being diminished by the expansion and deformation of the elastic member toward the outside of the liquid chamber.

[6] In the liquid discharge device of the above embodiment, the head main body portion has a plurality of the liquid chambers; the nozzle, the diaphragm, the drive portion, and the elastic member are in the liquid chamber, respectively. One for each; the head body, the plurality of diaphragms, the plurality of drive units, and the plurality of elastic members may be fastened by a common fastening portion.
According to this form of the liquid discharge device, a plurality of sets of drive parts, a diaphragm, an elastic member, and a head main body can be fastened with a single fastening part, so that the number of parts of the liquid discharge device can be reduced. be able to. In addition, the liquid discharge device can be miniaturized.

[7] In the liquid discharge device of the above-described embodiment, the fastening portion may have a plurality of individual adjusting portions for individually adjusting the compression amount of each of the elastic members as the adjusting portion.
According to this form of the liquid discharge device, the compression amount of each elastic member can be individually adjusted by the individual adjustment unit, so that the liquid discharge accuracy of each nozzle can be adjusted.

[8] In the liquid discharge device of the above-described embodiment, the fastening portion may have, as the adjusting portion, a common adjusting portion for commonly adjusting the compression amount of each of the elastic members.
According to this form of the liquid discharge device, the compression amount of the plurality of elastic members can be adjusted collectively, so that the liquid discharge accuracy can be efficiently adjusted.

[9] In the liquid discharge device of the above embodiment, the head main body is further a flow path of the liquid connected to the liquid chamber, and at least an inflow path for supplying the liquid to the liquid chamber. It may be provided with a flow path including the liquid chamber and a pressure transmission adjusting unit for controlling the inflow of the liquid from the liquid chamber to the flow path to adjust the transmission of pressure from the liquid chamber to the flow path.
According to this form of the liquid discharge device, by having the pressure transmission adjusting unit, it is possible to efficiently generate a pressure change for discharging the liquid in the liquid chamber, so that the liquid discharge efficiency is improved.

[10] The liquid discharge device of the above embodiment includes a control unit that controls the drive unit and the pressure transmission adjusting unit to execute a discharge process for discharging the liquid from the nozzle, and the control unit is the control unit. In the discharge process, (i) in a state where the transmission of pressure from the liquid chamber to the flow path is suppressed by the pressure transmission adjusting unit, the drive unit reduces the volume of the liquid chamber to reduce the volume of the liquid chamber. When a predetermined elapsed time elapses between the pressurizing process of increasing the pressure of the above and initiating the outflow of the liquid from the nozzle and (ii) the outflow of the liquid from the nozzle. At least one of a decompression process of reducing the pressure in the liquid chamber by driving at least one of the pressure transmission adjusting unit and the driving unit to separate droplets from the liquid of the nozzle and fly them. You may do one.
According to this form of the liquid discharge device, the liquid discharge efficiency and the controllability of the liquid discharge in the liquid discharge device can be improved by the pressurization treatment and the depressurization treatment.

[11] In the liquid discharge device of the above embodiment, the pressure transmission adjusting unit is an inflow amount changing unit that changes the volume of the inflow passage to change the inflow amount of the liquid from the inflow passage to the liquid chamber. The inflow path communicates with the liquid chamber through a connection opening opened in the liquid chamber, and the nozzle communicates with the liquid chamber through a communication port opened in the liquid chamber. The communication port may be located on the connection opening side of the center of the vibrating plate in the liquid chamber.
According to this form of the liquid discharge device, it is easy to efficiently transmit the pressure change caused by the operation of changing the volume of the inflow path by the inflow amount changing unit to the nozzle. Therefore, it is possible to improve the controllability of the pressure change in the liquid chamber by the inflow amount changing unit.

[12] In the liquid discharge device of the above embodiment, the head main body portion may further have an inflow path for flowing the liquid into the liquid chamber and an outflow path for flowing out the liquid in the liquid chamber. ..
According to this form of the liquid discharge device, it is possible to generate a flow of liquid from the inflow path to the outflow path in the liquid chamber. Therefore, it is possible to suppress the retention of the liquid in the liquid chamber, and it is possible to suppress the defective discharge of the liquid due to the retention of the liquid. In addition, the bubbles in the liquid chamber can be discharged together with the liquid from the outflow path, and the occurrence of poor discharge of the liquid due to the bubbles in the liquid chamber can be suppressed.

[13] In the liquid discharge device of the above embodiment, the flow path may further include an outflow path through which the liquid in the liquid chamber is discharged.
According to this form of the liquid discharge device, it is possible to suppress the liquid from staying in the liquid chamber due to the flow of the liquid from the inflow path to the outflow path, and it is possible to suppress the poor discharge of the liquid due to the retention of the liquid. In addition, air bubbles in the liquid chamber can be discharged together with the liquid from the outflow path.

[14] Another aspect of the present invention is provided as a method for manufacturing a liquid discharge device. In this embodiment of the manufacturing method, a vibrating plate constituting a part of the wall portion of the liquid chamber with respect to the head main body portion having the liquid chamber for accommodating the liquid and the nozzle for discharging the liquid in the liquid chamber. Is arranged with an elastic member sandwiched between the head body and the head body, the elastic member is elastically deformed to displace the vibrating plate, and an external force for discharging the liquid from the nozzle is applied to the vibrating plate. The assembly step of connecting the drive unit to the vibrating plate; the drive unit, the vibrating plate, and the head main body portion are fastened so as to support the vibrating plate in a state where the elastic member is compressed. The fastening process and; are provided. The fastening step includes a step of adjusting the compression amount of the elastic member.
According to the method for manufacturing a liquid discharge device of this form, it is possible to obtain a liquid discharge device in which the liquid discharge accuracy is adjusted by the amount of compression of the elastic member.

The plurality of components of each embodiment of the invention described above are not all essential, and may be used to solve some or all of the above-mentioned problems, or part or all of the effects described herein. In order to achieve the above, it is possible to change, delete, replace a part of the plurality of components with new other components, and partially delete the limited contents, as appropriate. Further, in order to solve a part or all of the above-mentioned problems, or to achieve a part or all of the effects described in the present specification, the technical features included in the above-mentioned embodiment of the present invention. It is also possible to combine some or all with some or all of the technical features contained in the other embodiments of the invention described above to form an independent embodiment of the invention.

The present invention can also be realized in various forms other than the liquid discharge device and its control method. For example, it can be realized as a liquid discharge system or a head portion for discharging a liquid. In addition, it can be realized in the form of a liquid discharge device, a liquid discharge system, a method for manufacturing and assembling a head portion, a method for adjusting discharge characteristics, and the like.

The schematic block diagram which shows the structure of the liquid discharge apparatus in 1st Embodiment. Schematic exploded perspective view of the head portion in the first embodiment. The schematic sectional view of the head part in 1st Embodiment. The first explanatory view which shows the change of the ejection characteristic of a head part by the compression amount of an elastic member. The second explanatory view which shows the change of the ejection characteristic of a head part by the compression amount of an elastic member. The flow chart of the manufacturing process of the liquid discharge apparatus of 1st Embodiment. FIG. 3 is a schematic cross-sectional view of a head portion included in the liquid discharge device of the second embodiment. FIG. 3 is a schematic cross-sectional view of a head portion included in the liquid discharge device of the third embodiment. FIG. 6 is a schematic exploded perspective view of a head portion included in the liquid discharge device of the fourth embodiment. A schematic exploded perspective view of a head portion included in the liquid discharge device of the fifth embodiment. FIG. 6 is a schematic cross-sectional view of a head portion included in the liquid discharge device of the sixth embodiment. The flow chart which shows the control process in the discharge process of 6th Embodiment. FIG. 6 is a schematic cross-sectional view of a head portion included in the liquid discharge device of the seventh embodiment.

A. First Embodiment:
FIG. 1 is a schematic block diagram showing the overall configuration of the liquid discharge device 100A according to the first embodiment. The liquid discharge device 100A of the first embodiment includes a tank 10, a pressurizing pump 11, a supply path 12, a discharge path 15, a liquid storage unit 16, a negative pressure generation source 17, a circulation path 18, and a head. A unit 20A and a control unit 25 are provided.

The tank 10 contains a liquid. The liquid is, for example, an ink having a predetermined viscosity. The liquid in the tank 10 is supplied to the head portion 20A through the supply path 12 connected to the head portion 20A. The pressurizing pump 11 supplies the liquid in the tank 10 to the head portion 20A through the supply path 12.

The head portion 20A discharges the liquid supplied from the supply path 12. The operation of the head unit 20A is controlled by the control unit 25. The configuration of the head portion 20A will be described later. The discharge passage 15 connects the head portion 20A and the liquid storage portion 16. The liquid not discharged by the head unit 20A is discharged to the liquid storage unit 16 through the discharge path 15.

A negative pressure generation source 17 is connected to the liquid storage unit 16. The negative pressure generation source 17 sucks the liquid from the head portion 20A through the discharge passage 15 by making the inside of the liquid storage portion 16 negative pressure. The negative pressure generation source 17 is composed of various pumps.

In the liquid discharge device 100A, the pressurizing pump 11 and the negative pressure generation source 17 function as a liquid supply unit that generates a differential pressure between the supply path 12 and the discharge path 15 to supply the liquid to the head portion 20A. It should be noted that either the pressure pump 11 or the negative pressure generation source 17 may be omitted, and the liquid supply unit may be configured by either the pressure pump 11 or the negative pressure generation source 17 alone.

The circulation path 18 is a flow path for circulating the liquid discharged from the head portion 20A through the discharge passage 15 to the head portion 20A again. The circulation path 18 connects the liquid storage unit 16 and the tank 10. The liquid discharged from the head portion 20A and stored in the liquid storage portion 16 through the discharge passage 15 is returned to the tank 10 through the circulation passage 18 and is again supplied to the head portion 20A by the pressurizing pump 11. The circulation passage 18 may be provided with a pump for sucking the liquid from the liquid storage unit 16.

Since the liquid discharge device 100A includes the circulation path 18, the liquid discharged from the head portion 20A can be reused. Therefore, it is possible to prevent the liquid from being wasted, and the efficiency of using the liquid is improved. The liquid storage unit 16 and the tank 10 may be provided with an adjustment unit for adjusting various states such as the concentration, viscosity, and temperature of the liquid to be reused. Further, the discharge passage 15 and the circulation passage 18 may be provided with a filter portion for removing air bubbles and foreign substances contained in the liquid.

The control unit 25 is configured as a computer equipped with a CPU and a memory, and has various functions for controlling the liquid discharge device 100A by reading and executing control programs and instructions stored in the memory by the CPU. Realize. The control program may be recorded on various non-temporary tangible recording media. The control unit 25 may be configured by a circuit. The control unit 25 controls, for example, the voltage applied to the drive unit (described later) of the head unit 20A to execute a discharge process for discharging the liquid to the head unit 20A.

The configuration of the head portion 20A of the first embodiment will be described with reference to FIGS. 2 and 3. FIG. 2 is a schematic exploded perspective view of the head portion 20A. FIG. 3 is a schematic cross-sectional view of the head portion 20A in the 3-3 cutting shown in FIG. In FIG. 3, the pedestal portion 51 is not shown.

The head portion 20A includes a head main body portion 30, a diaphragm 40, an elastic member 42, a drive portion 45, and a fastening portion 50 (FIG. 3). The head body portion 30 has an internal space SP. The internal space SP of the head main body 30 constitutes a liquid chamber 31, an inflow path 32, an outflow path 33, and a nozzle 35.

The liquid chamber 31 accommodates the liquid LQ discharged by the head portion 20A and functions as a pressure chamber as described later. The inflow path 32 is a flow path for flowing the liquid LQ into the liquid chamber 31. The outflow passage 33 is a flow path through which the liquid LQ flows out from the liquid chamber 31. In the first embodiment, the liquid chamber 31 is configured as a space having a substantially cylindrical shape. The inflow path 32 and the outflow path 33 are configured as linear flow paths formed at positions facing each other with the liquid chamber 31 interposed therebetween.

The inflow path 32 is provided with a valve section that controls the flow of the liquid LQ in the inflow path 32 under the control of the control section 25 (not shown). The valve portion is realized by a configuration in which the flow path resistance of the inflow path 32 is changed by displacing the wall surface of the inflow path 32 by an actuator such as a piezo element and changing the opening cross-sectional area of the inflow path 32. .. The valve portion of the inflow path 32 may be omitted. Further, a similar valve portion may be provided in the outflow path 33.

The head main body 30 has a nozzle 35 that communicates with the liquid chamber 31 and discharges the liquid LQ of the liquid chamber 31. In the first embodiment, the nozzle 35 is composed of a through hole that opens at the bottom surface of the liquid chamber 31. The nozzle 35 has a tapered portion 35t whose diameter is reduced toward the discharge port 35o that opens at the bottom surface of the head main body portion 30.

The head body portion 30 has an opening 36, an inflow port 37, and an outflow port 38. The internal space of the opening 36 constitutes a part of the liquid chamber 31. In the first embodiment, the opening shape of the opening 36 is substantially circular. The opening 36 is closed by the diaphragm 40, as will be described later.

The inflow port 37 is open at the upstream end of the inflow path 32. A supply path 12 is connected to the inflow port 37. The outlet 38 is open at the downstream end of the outflow channel 33. A discharge path 15 is connected to the outlet 38.

In the first embodiment, the head main body portion 30 is configured by laminating three laminated plates 30a, 30b, and 30c (FIG. 2). Each of the laminated plates 30a to 30c is composed of a flat metal plate having a quadrangular surface, and has substantially the same size other than the thickness. The plate surface of each of the laminated plates 30a to 30c does not have a substantially quadrangular shape, and may have a circular shape, for example. Further, the thicknesses of the laminated plates 30a to 30c may be substantially the same, or the size and shape of the plate surfaces may be different from each other. Further, each of the laminated plates 30a to 30c may be made of different kinds of metals. Each laminated plate 30a to 30c may be made of a material other than metal. The boundary surfaces of the laminated plates 30a to 30c are airtightly bonded.

The first laminated plate 30a constitutes the bottom wall portion of the liquid chamber 31. The first laminated plate 30a is provided with a through hole constituting the nozzle 35. The second laminated plate 30b is laminated on the first laminated plate 30a. In the center of the second laminated plate 30b, a through hole 31p having a substantially circular cross section forming a part of the liquid chamber 31 and a slit 32s connected to the through hole 31p to form an inflow path 32 and an outflow path 33. , 33s, and are formed. The third laminated plate 30c is laminated on the second laminated plate 30b. The third laminated plate 30c is provided with an opening 36, an inflow port 37, and an outflow port 38 as through holes.

The diaphragm 40 is arranged so as to close the opening 36 of the head main body 30 (FIG. 2). The diaphragm 40 constitutes a part of the wall portion of the liquid chamber 31 (FIG. 3). In the first embodiment, the diaphragm 40 is arranged on the third laminated plate 30c and constitutes the upper surface wall portion of the liquid chamber 31. The diaphragm 40 is composed of, for example, a metal plate.

The elastic member 42 is arranged between the head main body 30 and the diaphragm 40 (FIG. 2). The elastic member 42 supports the diaphragm 40. As will be described later, the elastic member 42 supports the diaphragm 40 in a state of being compressed by the fastening force of the fastening portion 50. In the first embodiment, the elastic member 42 is composed of an annular resin member and is arranged on the upper surface of the third laminated plate 30c so as to surround the opening 36 (FIG. 3). The elastic member 42 is made of, for example, a thermoplastic elastomer material such as urethane-based, styrene-based, olefin-based, ester-based, amide-based, PVC-based, or fluorine. More specifically, diene rubber such as styrene / butadiene rubber, isoprene rubber, acrylonitrile / butadiene rubber, and non-diene rubber such as butyl rubber (IIR) urethane rubber, ethylene / propylene / diene rubber, silicone rubber, and fluororubber. Consists of rubber. Further, it may be composed of a plastic material also called a super engineering plastic such as PEEK, PPS, PC, PE, PP or other general-purpose plastic material. Alternatively, the elastic member 42 may be made of polyurethane, a curable resin such as an epoxy resin, a melamine resin, or a silicon resin. The resin material constituting the elastic member 42 is not limited to the above-mentioned material amount.

In the first embodiment, the elastic member 42 is configured as a replaceable O-ring. In the first embodiment, the space on the inner circumference of the elastic member 42 constitutes a part of the liquid chamber 31, and the inner peripheral surface thereof constitutes a part of the wall surface of the liquid chamber 31 (FIG. 2). The elastic member 42 also functions as a sealing portion for suppressing leakage of the liquid LQ.

The drive unit 45 is connected to the diaphragm 40 (FIG. 3). The drive unit 45 is arranged so that an external force can be applied to the diaphragm 40. The drive unit 45 elastically deforms the elastic member 42 to displace the diaphragm 40, and applies an external force to discharge the liquid LQ from the nozzle 35 to the diaphragm 40. In the first embodiment, the drive unit 45 is composed of a piezoelectric element. The drive unit 45 is arranged so as to expand and contract in the stacking direction of the diaphragm 40 and the elastic member 42. The stacking direction of the diaphragm 40 and the elastic member 42 is also a direction from the diaphragm 40 toward the nozzle 35.

In the first embodiment, the bottom surface of the drive unit 45 in contact with the diaphragm 40 is formed of a flat surface capable of pressing the entire upper surface of the elastic member 42. As a result, the diaphragm 40 is prevented from bending and deforming when the drive unit 45 is expanded and contracted. In the first embodiment, the drive portion 45 and the diaphragm 40 are not provided with an adhesive portion made of an adhesive material or a joint portion made of welding, welding, or the like.

The fastening portion 50 fastens the head main body portion 30, the diaphragm 40, and the drive portion 45 (FIG. 2). In the first embodiment, the fastening portion 50 includes a pedestal portion 51, a support member 52, a fastening screw 53, a pressing plate 54, and an adjusting screw 55. The pedestal portion 51 has a base portion 60 and two side wall portions 63, 64.

The base portion 60 is composed of a plate-shaped member on which the head main body portion 30 is laminated. The upper surface of the base portion 60 is provided with a recess 61 into which the head main body portion 30 is fitted and fixed. The bottom surface of the recess 61 is provided with an opening 62 for exposing the nozzle 35 provided on the bottom surface of the head main body 30 from the lower surface of the base 60.

The first side wall portion 63 and the second side wall portion 64 are erected on the upper surface of the base portion 60 so as to project upward. The first side wall portion 63 and the second side wall portion 64 are arranged at positions facing each other with the head main body portion 30 interposed therebetween. Screw holes 65 for screwing the fastening screw 53 are provided on the upper end surfaces of the first side wall portion 63 and the second side wall portion 64, respectively.

The support member 52 is a plate-shaped beam member, which is arranged above the head main body portion 30, the diaphragm 40, and the drive portion 45, and is substantially horizontal over the upper end surfaces of the two side wall portions 63 and 64 of the base portion 60. It is erected in. Through holes 52p into which fastening screws 53 are inserted are provided at both ends of the support member 52 in the horizontal direction. Further, in the center of the support member 52, an adjustment screw hole 52s is provided which penetrates the support member 52 and has a screw groove (not shown) to which the adjustment screw 55 is screwed. The adjusting screw hole 52s is located above the drive unit 45.

The pressing plate 54 is arranged between the support member 52 and the driving unit 45. The pressing plate 54 is arranged below the adjusting screw hole 52s of the support member 52.

The support member 52 is fixed to the base portion 60 by screwing the fastening screw 53 into the screw holes 65 of the side wall portions 63 and 64 of the base portion 60. When the support member 52 is fixed to the base portion 60, the drive portion 45 receives a pressing force from the support member 52 in the stacking direction of the diaphragm 40 and the drive portion 45 via the pressing plate 54. Using this pressing force as a fastening force, the head main body portion 30, the diaphragm 40, and the driving portion 45 are fastened. Further, the elastic member 42 supporting the diaphragm 40 is put into a compressed state by the fastening force.

When the adjusting screw 55 is screwed into the adjusting screw hole 52s of the support member 52 and its tip protrudes from the adjusting screw hole 52s, the tip of the adjusting screw 55 causes the pressing plate 54 to move toward the drive portion 45. Pressed (Fig. 3). As a result, the elastic member 42 is further compressed. The amount of compression of the elastic member 42 can be adjusted by adjusting the length of the adjusting screw 55 protruding from the support member 52 through the adjusting screw hole 52s.

The "compression amount of the elastic member 42" is the thickness of the elastic member 42 when no external force is applied, and when the drive portion 45 is not driven and is compressed by the fastening force from the fastening portion 50. It means the absolute value of the difference in the thickness of the elastic member 42 of. The "thickness of the elastic member 42" means the height of the elastic member 42 in the direction of being pressed by the diaphragm 40 when assembled to the head portion 20A. Further, the "state in which the drive unit 45 is not driven" is a state in which a voltage for expansion / contraction deformation is not applied to the drive unit 45. The "state in which the drive unit 45 is not driven" can also be interpreted as a state in which the drive unit 45 is stationary at a predetermined reference length.

As described above, in the head portion 20A, the support member 52, the pressing plate 54, and the adjusting screw 55 function as the adjusting portion 70 for adjusting the compression amount of the elastic member 42. The pressing plate 54 may be omitted. As will be described later, in the liquid discharge device 100A of the first embodiment, the discharge characteristics of the head portion 20A are adjusted by adjusting the compression amount of the elastic member 42.

The liquid LQ discharge operation by the head portion 20A will be described with reference to FIG. First, the control unit 25 sets the length of the drive unit 45 in the expansion / contraction direction to a predetermined reference length. In the first embodiment, the reference length is the length when no voltage is applied to the drive unit 45. Further, the control unit 25 controls the pressurizing pump 11 and the negative pressure generation source 17 shown in FIG. 1 to set the pressure of the liquid chamber 31 to a predetermined reference pressure equal to or lower than the meniscus pressure resistance of the nozzle 35. Adjust to.

When the liquid LQ discharge timing arrives, the control unit 25 instantaneously extends the drive unit 45 by a length corresponding to the liquid LQ discharge amount. As a result, the diaphragm 40 is pressed against the drive unit 45, the elastic member 42 elastically contracts, the diaphragm 40 is displaced toward the liquid chamber 31, and the pressure for discharging the liquid LQ into the liquid chamber 31 is increased. Occurs. Using this pressure as a driving force, the outflow of droplets from the nozzle 35 is started. After that, the control unit 25 instantaneously contracts the drive unit 45 to the initial reference length. Then, the diaphragm 40 is displaced by following the lower end portion of the drive unit 45 due to the elastic force of the elastic member 42, and a negative pressure is generated in the liquid chamber 31. Due to this negative pressure, the droplets are separated from the liquid LQ of the nozzle 35, and the droplets fly toward the ejection target.

With reference to FIGS. 4A and 4B, adjustment of the discharge characteristic of the head portion 20A by adjusting the compression amount of the elastic member 42 will be described. FIG. 4A is a graph showing the change in the speed of the diaphragm 40 with respect to the drive frequency of the drive unit 45 when the compression amount of the elastic member 42 is adjusted to a, b (0 <a <b). The graphs G1a and G2a are graphs when the compression amount of the elastic member 42 is a, and the graphs G1b and G2b are graphs when the compression amount of the elastic member 42 is b. Graphs G1a and G1b show the speed of the diaphragm 40 when the drive unit 45 extends, and graphs G2a and G2b show the speed of the diaphragm 40 when the drive unit 45 contracts. FIG. 4B is a graph showing the change in the displacement amount of the diaphragm 40 with respect to the drive frequency of the drive unit 45 when the compression amount of the elastic member 42 is adjusted to a and b. The graph Ga is a graph when the compression amount of the elastic member 42 is a, and the graph Gb is a graph when the compression amount of the elastic member 42 is b.

As shown in the graphs of FIGS. 4A and 4B, the inventor of the present invention experimentally changed the displacement speed of the diaphragm 40 with respect to the drive frequency of the drive unit 45 by changing the compression amount of the elastic member 42. We obtained the finding that the amount of displacement changes. The speed and the amount of displacement of the diaphragm 40 affect the discharge characteristics of the liquid LQ in the head portion 20A. This means that the discharge characteristics of the liquid LQ of the head portion 20A can be changed by changing the compression amount of the elastic member 42.

In the present specification, the "discharge characteristic of the liquid LQ of the head unit 20A" means the response performance to a constant pulse signal applied to the drive unit 45 for discharging the liquid LQ. The discharge characteristics of the liquid LQ of the head portion 20A can be known from the response results such as the discharge amount of the liquid LQ when the pulse signal is applied, the discharge speed of the liquid LQ, and the timing at which the discharge of the liquid LQ is started. can.

Here, the discharge accuracy of the liquid LQ of the head portion 20A is determined by the discharge characteristics of the liquid LQ of the head portion 20A, and changes depending on the drive conditions of the drive unit 45. The “liquid LQ ejection accuracy” means the accuracy with respect to the flight state and the landing state of the target droplet. The "driving condition of the driving unit 45" includes the magnitude of the applied voltage, the period of the pulse voltage which is the driving cycle of the driving unit 45, and the type and viscosity of the liquid LQ to which the external force is applied.

In the liquid discharge device 100A of the first embodiment, the amount of compression of the elastic member 42 by the fastening portion 50 is adjusted according to the drive conditions of the drive portion 45 so that a constant standard discharge accuracy can be obtained. Whether or not the compression amount of the elastic member 42 is adjusted according to the drive condition of the drive unit 45 is determined by changing the compression amount of the elastic member 42 between the liquid discharge devices 100A in which the drive condition is changed. It can be verified by whether or not it is present.

As described above, according to the liquid discharge device 100A, the discharge accuracy of the liquid LQ can be appropriately adjusted according to the drive conditions of the drive unit 45 by compressing the elastic member 42 by the fastening portion 50. In particular, in the liquid discharge device 100A of the first embodiment, the fastening portion 50 has an adjusting portion 70, and the compression amount of the elastic member 42 can be easily adjusted by the adjusting screw 55 of the adjusting portion 70.

The manufacturing process of the liquid discharge device 100A will be described with reference to FIGS. 2 and 5. FIG. 5 is a flow chart showing a manufacturing process of the head portion 20A of the liquid discharge device 100A. Step 1 is an assembly step of laminating each member constituting the discharge mechanism of the head portion 20A. In step 1, the manufacturer first laminates the three laminated plates 30a, 30b, and 30c to form the head main body portion 30. Then, the diaphragm 40 forming a part of the wall portion of the liquid chamber 31 is arranged above the liquid chamber 31 with respect to the head main body portion 30. At this time, the elastic member 42 is sandwiched between the head body 30 and the diaphragm 40. Further, a drive unit 45 is installed above the diaphragm 40, and the diaphragm 40 and the drive unit 45 are connected to each other.

Step 2 is a fastening step of fastening the drive portion 45, the diaphragm 40, and the head main body portion 30 so as to support the diaphragm 40 in a compressed state of the elastic member 42. In step 2, the manufacturer arranges the head main body portion 30 in which the elastic member 42, the diaphragm 40, and the drive portion 45 are laminated in the recess 61 of the base portion 60 of the fastening portion 50. Next, the pressing plate 54 is arranged on the drive unit 45, and the support member 52 is further arranged on the pressing plate 54. Then, the pedestal portion 51 and the support member 52 are fastened by the fastening screw 53. This fastening force brings the elastic member 42 into a compressed state.

Step 2 includes a step of adjusting the amount of compression of the elastic member 42. In step 2, the manufacturer adjusts the compression amount of the elastic member 42 to a suitable value obtained by the test in advance according to the predetermined driving condition of the driving unit 45 by the adjusting unit 70. For example, the manufacturer adjusts the compression amount of the elastic member 42 so that the target displacement speed and the target displacement amount of the diaphragm 40 can be obtained with respect to the drive frequency of the drive unit 45. Alternatively, the compression amount of the elastic member 42 is adjusted so that the target displacement speed and the target displacement amount of the diaphragm 40 can be obtained with respect to the viscosity of the liquid LQ to be discharged. In this way, the manufacturer adjusts the compression amount of the elastic member 42 so that the target liquid LQ discharge performance can be obtained with respect to the drive conditions of the drive unit 45. When adjusting the compression amount of the elastic member 42 in the step 2, the drive unit 45 is expanded and contracted to a reference length in advance. The reference length of the drive unit 45 may be, for example, the reference length at the time of the discharge process described above, or the length when the drive unit 45 is most extended.

According to the liquid discharge device 100A of the first embodiment, in the above-mentioned discharge process, it is possible to generate a pressure for discharging the liquid LQ into the liquid chamber 31 without substantially bending and deforming the diaphragm 40. Therefore, the external force applied to the diaphragm 40 by the drive unit 45 is suppressed from being absorbed by the elastic deformation of the diaphragm 40, so that the energy loss for discharging the liquid LQ is reduced. Therefore, the liquid LQ can be efficiently discharged.

In particular, in the liquid discharge device 100A of the first embodiment, as described above, the bottom surface of the drive unit 45 is formed of a flat surface capable of pressing the entire upper surface of the elastic member 42. As a result, the bending deformation of the diaphragm 40 due to the driving of the driving unit 45 is further suppressed, and the energy loss due to the discharge of the liquid LQ is further reduced.

According to the liquid discharge device 100A of the first embodiment, the diaphragm 40 and the drive unit 45 are fastened by the fastening portion 50 in a state where the elastic member 42 is compressed. As a result, it is possible to prevent the diaphragm 40 and the drive unit 45 from being separated from each other even when the drive unit 45 is instantaneously contracted in the discharge process. As described above, by fastening the diaphragm 40 and the drive portion 45 by the fastening portion 50, the followability of the diaphragm 40 to the expansion and contraction of the drive portion 45 is enhanced, and the discharge accuracy of the liquid LQ is enhanced.

In the liquid discharge device 100A of the first embodiment, the adhesive portion and the joint portion between the diaphragm 40 and the drive portion 45 are omitted. Therefore, the manufacturing process of the liquid discharge device 100A can be simplified and the manufacturing cost can be reduced by the amount that the processing process and the control process for bonding and joining the diaphragm 40 and the drive unit 45 can be omitted. Manufacturing efficiency is improved. Further, when the drive unit 45 is driven at a high frequency, the adhesive portion and the joint portion between the diaphragm 40 and the drive unit 45 deteriorate, and the diaphragm 40 and the drive unit 45 are separated from each other. The occurrence of problems is suppressed.

According to the liquid discharge device 100A of the first embodiment, the compression amount of the elastic member 42 is adjusted according to the drive conditions of the drive unit 45 described above. Therefore, it is possible to suppress that the discharge accuracy of the liquid LQ of the liquid discharge device 100A varies depending on the drive conditions of the drive unit 45. Further, according to the liquid discharge device 100A of the first embodiment, since the adjusting portion 70 for adjusting the compression amount of the elastic member 42 is provided in the fastening portion 50, the compression amount of the elastic member 42 can be adjusted. It can be done easily and accurately.

According to the manufacturing process of the liquid discharge device 100A of the first embodiment, the head portion 20A of the liquid discharge device 100A can be manufactured by a simple laminating work and fastening work of the members. Further, by adjusting the compression amount of the elastic member 42 in the head portion 20A, it is possible to suppress the occurrence of variation in the discharge performance of the liquid discharge device 100A.

As described above, according to the liquid discharge device 100A of the first embodiment, the followability of the diaphragm 40 to the drive unit 45 is enhanced by the elastic member 42 arranged in the compressed state, and the liquid is discharged. The discharge accuracy of the liquid LQ of the device 100A is improved. Further, the discharge characteristics of the liquid LQ of the liquid discharge device 100A are appropriately adjusted by the compression amount of the elastic member 42, and the occurrence of variation in the discharge accuracy of the liquid LQ of the liquid discharge device 100A is suppressed. In addition, according to the liquid discharge device 100A of the first embodiment and the manufacturing method thereof, various effects described in the above-described embodiment can be obtained.

B. Second embodiment:
FIG. 6 is a schematic cross-sectional view showing the configuration of the head portion 20B included in the liquid discharge device 100B of the second embodiment. The configuration of the liquid discharge device 100B of the second embodiment is the liquid discharge device 100A of the first embodiment except that the head portion 20B of the second embodiment is provided instead of the head portion 20A of the first embodiment. It is almost the same as the configuration of (Fig. 1). The configuration of the head portion 20B of the second embodiment is substantially the same as the configuration of the head portion 20A of the first embodiment except that the spacer 72 is provided.

The spacer 72 is provided between the diaphragm 40 and the head body 30. The spacer 72 is a member for limiting the compression of the elastic member 42. In the second embodiment, the spacer 72 is composed of an annular member and is arranged so as to surround the elastic member 42. The thickness of the spacer 72 is smaller than the thickness of the elastic member 42 when the drive unit 45 is not driven. The "thickness of the spacer 72" means the height of the spacer 72 in the stacking direction of the diaphragm 40 and the elastic member 42. The thickness of the spacer 72 is larger than the limit thickness of the elastic member 42 in which the elastic force of the elastic member 42 is significantly reduced by compression.

According to the head portion 20A of the second embodiment, when the drive portion 45 is extended or the compression amount of the elastic member 42 is increased by the adjusting portion 70, the spacer 72 causes the elastic member 42 to exceed the limit. It is suppressed that it is compressed too much. Therefore, deterioration of the elastic member 42 due to compression is suppressed, and deterioration of the discharge accuracy of the liquid LQ of the liquid discharge device 100B due to deterioration of the elastic member 42 is suppressed. In addition, according to the liquid discharge device 100B of the second embodiment, various effects described in the first embodiment can be obtained.

C. Third embodiment:
FIG. 7 is a schematic cross-sectional view showing the configuration of the head portion 20C included in the liquid discharge device 100C of the third embodiment. The configuration of the liquid discharge device 100C of the third embodiment is the liquid discharge device 100A of the first embodiment except that the head portion 20C of the third embodiment is provided instead of the head portion 20A of the first embodiment. Is almost the same as (Fig. 1). The configuration of the head portion 20C of the third embodiment is substantially the same as the configuration of the head portion 20A of the first embodiment except that the inclined wall surface 75 is provided on the inner peripheral edge of the opening 36.

In the head portion 20C of the third embodiment, the head main body portion 30 surrounds the liquid chamber 31 below the diaphragm 40, is inclined downward toward the liquid chamber 31, and has an inclined wall surface 75 facing the diaphragm 40. Have. The inclined wall surface 75 is inclined with respect to the direction in which the diaphragm 40 is displaced. The elastic member 42 is arranged so as to be sandwiched between the inclined wall surface 75 and the diaphragm 40.

In the head portion 20C, when the diaphragm 40 is displaced by the drive portion 45, the elastic member 42 expands toward the outside of the liquid chamber 31 in a direction orthogonal to the displacement direction of the diaphragm 40. It is suppressed by the wall surface 75. Therefore, it is suppressed that the energy for discharging the liquid LQ is absorbed and reduced due to the expansion and deformation of the elastic member 42. Therefore, the discharge efficiency of the liquid LQ in the liquid discharge device 100C is enhanced. In addition, according to the liquid discharge device 100C of the third embodiment, various effects described in the first embodiment can be obtained.

D. Fourth Embodiment:
FIG. 8 is a schematic exploded perspective view of the head portion 20D included in the liquid discharge device 100D of the fourth embodiment. The configuration of the liquid discharge device 100D of the fourth embodiment is the liquid discharge device 100A of the first embodiment except that the head portion 20D of the fourth embodiment is provided instead of the head portion 20A of the first embodiment. Is almost the same as (Fig. 1).

In the head portion 20D of the fourth embodiment, the head main body portion 30D has a plurality of liquid chambers 31. FIG. 8 illustrates a configuration in which the head main body 30D has two liquid chambers 31. The number of liquid chambers 31 included in the head body portion 30D is not limited to two. The head body portion 30D may have three or more liquid chambers 31.

The first laminated plate 30a constituting the head main body portion 30D is provided with one through hole constituting the nozzle 35 for each of the plurality of liquid chambers 31. The second laminated plate 30b is provided with a plurality of through holes 31p constituting the liquid chamber 31, and slits 32s forming the inflow passage 32 and slits 33s forming the outflow passage 33 for each liquid chamber 31. The third laminated plate 30c is provided with one opening 36 for each of the plurality of liquid chambers 31. Further, one through hole constituting the inflow port 37 is provided for each of the plurality of liquid chambers 31, and one through hole constituting the outflow port 38 is provided for each of the plurality of liquid chambers 31. Has been done.

In the head portion 20D, the diaphragm 40, the drive portion 45, and the elastic member 42 are provided one by one corresponding to each of the plurality of liquid chambers 31. The pressing plate 54 of the fastening portion 50 is arranged so as to straddle the upper ends of the plurality of driving portions 45. As a result, in the head portion 20D, the plurality of diaphragms 40, the plurality of drive portions 45, and the plurality of elastic members 42 are fastened by the common fastening portion 50. Further, the adjusting portion 70 of the fastening portion 50 functions as a common adjusting portion that collectively adjusts the compression amount of each of the plurality of elastic members 42.

According to the liquid discharge device 100D of the fourth embodiment, since a plurality of sets of drive units 45 and the diaphragm 40 can be fastened with one fastening portion 50, the number of parts can be reduced and the manufacturing process can be performed. It is possible to simplify the process and reduce the manufacturing cost. Further, the liquid discharge device 100D can be downsized. According to the liquid discharge device 100D of the fourth embodiment, the compression amount of the plurality of elastic members 42 can be collectively adjusted by the adjustment unit 70 which is a common adjustment unit, so that the discharge accuracy of the liquid LQ can be efficiently adjusted. be able to. In addition, according to the liquid discharge device 100D of the fourth embodiment, various effects described in the first embodiment can be obtained.

E. Fifth Embodiment:
FIG. 9 is a schematic exploded perspective view of the head portion 20E included in the liquid discharge device 100E of the fifth embodiment. The configuration of the liquid discharge device 100E of the fifth embodiment is the liquid discharge device 100A of the first embodiment except that the head portion 20E of the fifth embodiment is provided instead of the head portion 20A of the first embodiment. It is almost the same as the composition of. The configuration of the head portion 20E of the fifth embodiment is substantially the same as the configuration of the head portion 20D of the fourth embodiment except that the fastening portion 50E has the individual adjustment portion 70E instead of the adjustment portion 70. Is.

The configuration of the fastening portion 50E of the fifth embodiment has a plurality of pressing plates 54 and a plurality of adjusting screws 55, except that the support member 52E is provided with a plurality of adjusting screw holes 52s. 4 It is almost the same as the fastening portion 50 of the embodiment. The number of each of the pressing plate 54, the adjusting screw 55, and the adjusting screw hole 52s is the same as the number of the liquid chambers 31 included in the head portion 20E. FIG. 9 illustrates a configuration in which two pressing plates 54, two adjusting screws 55, and two adjusting screw holes 52s are provided for each of the two liquid chambers 31.

The plurality of pressing plates 54 are arranged one above each of the plurality of driving units 45. The plurality of adjusting screw holes 52s are provided one above each of the plurality of drive units 45. Each of the plurality of adjusting screws 55 is inserted into the corresponding adjusting screw hole 52s, and a pressing force is applied to one drive unit 45 arranged below the adjusting screw hole 52s to press the elastic member 42 under the pressing force. Compress. In the head portion 20E, the support member 52E, the plurality of pressing plates 54, and the plurality of adjusting screws 55 function as individual adjusting portions 70E for individually adjusting the compression amount of each of the plurality of elastic members 42. The plurality of pressing plates 54 may be omitted.

According to the liquid discharge device 100E of the fifth embodiment, the compression amount of each elastic member 42 can be individually adjusted by the individual adjustment unit 70E, so that the discharge accuracy of the liquid LQ from each of the plurality of nozzles 35 can be adjusted. become. Therefore, the discharge characteristics of the liquid LQ can be adjusted so that the discharge characteristics of each nozzle 35 do not vary. Alternatively, the discharge characteristics of the liquid LQ can be changed for each nozzle 35. For example, the discharge characteristics of the liquid LQ can be adjusted for each nozzle 35 so as to match the drive conditions of the corresponding drive unit 45. In addition, according to the liquid discharge device 100E of the fifth embodiment, various actions and effects described in the fourth embodiment can be obtained.

F. Sixth Embodiment:
FIG. 10 is a schematic view showing the configuration of the head portion 20F included in the liquid discharge device 100F according to the sixth embodiment. The configuration of the liquid discharge device 100F of the sixth embodiment is almost the same as the configuration of the liquid discharge device 100A of the first embodiment except that the head portion 20F of the sixth embodiment is provided instead of the head portion 20A. (Fig. 1). In the configuration of the head portion 20F of the sixth embodiment, the head portion of the first embodiment is configured except that the inflow amount changing unit 80 is connected to the inflow path 32 and the outflow amount changing unit 90 is connected to the outflow path 33. It is almost the same as the configuration of 20A.

The inflow amount changing unit 80 adjusts the inflow amount of the liquid LQ into the liquid chamber 31 under the control of the control unit 25. As will be described later, the inflow amount changing unit 80 is a pressure transmission adjusting unit that controls the inflow of the liquid LQ from the liquid chamber 31 to the inflow passage 32F and adjusts the transmission of the pressure from the liquid chamber 31 to the inflow passage 32F. Function.

The inflow amount changing unit 80 includes an additional inflow path 81, a drive chamber 83, a valve body 85, and a drive unit 86. The additional inflow path 81 is a flow path of the liquid LQ connected to the inflow path 32. In the head portion 20F of the sixth embodiment, the inflow path 32 and the additional inflow path 81 form an inflow path 32F for supplying the liquid LQ to the liquid chamber 31.

The drive chamber 83 is a room provided in the housing of the head portion 20F, and accommodates the drive portion 86. In the sixth embodiment, the drive chamber 83 is provided above the additional inflow path 81. The additional inflow path 81 and the drive chamber 83 are communicated with each other by a through hole 84 extending in a straight line.

The valve body 85 is a metal columnar member. The valve body 85 is arranged so as to straddle the additional inflow path 81 and the drive chamber 83 via the above-mentioned through hole 84. Hereinafter, the end portion of the valve body 85 on the additional inflow path 81 side is referred to as a "tip portion", and the end portion on the drive chamber 83 side is referred to as a "rear end portion". The valve body is arranged so that its longitudinal direction is along the direction of gravity, with the tip end facing down and the rear end end facing up. In the sixth embodiment, the tip portion of the valve body 85 is configured as a hemispherical convex portion. It can be interpreted that the surface of the valve body 85 arranged in the additional inflow path 81 constitutes a part of the inner wall surface of the inflow path 32F in the head portion 20F.

The drive unit 86 is connected to the rear end portion of the valve body 85, and applies an external force to the valve body 85 to displace the valve body 85 along its longitudinal direction. In the sixth embodiment, the drive unit 86 is composed of a piezo element, and by expanding and contracting in the vertical direction in the drive chamber 83, the valve body 85 is moved up and down by a piston. In the through hole 84, a sealing member that comes into contact with the side surface of the valve body 85 and airtightly seals the drive chamber 83 is arranged (not shown). The valve body 85 makes a piston movement while rubbing the inner peripheral surface of the seal portion.

FIG. 10 illustrates a state in which the drive unit 86 contracts and the length of the valve body 85 protruding into the additional inflow path 81 is the shortest. When the drive unit 86 extends from this state, the valve body 85 moves downward, the length of the valve body 85 protruding into the additional inflow path 81 increases, the volume of the inflow path 32F is reduced, and the inflow path 32F is reduced. Flow path resistance increases. On the contrary, when the drive unit 86 contracts, the volume of the inflow path 32F increases, and the flow path resistance of the inflow path 32F is reduced.

In the sixth embodiment, the additional inflow path 81 has a valve seat portion 82. The valve seat portion 82 is provided at a position facing the tip end portion of the valve body 85. The valve seat portion 82 is configured as a tapered portion whose diameter gradually decreases in the moving direction when the valve body 85 moves toward the additional inflow path 81. When the valve body 85 protrudes most into the additional inflow path 81, its tip comes into contact with the inner wall surface of the valve seat portion 82 and closes the inflow path 32F. In the state where the inflow path 32F is blocked, the flow of the liquid LQ in the inflow path 32F may not be completely blocked. As described above, in the sixth embodiment, the inflow amount changing unit 80 moves the valve body 85 in the direction in which the flow path resistance of the inflow path 32F increases, and closes the inflow path 32F. Further, the valve body 85 is moved in the direction in which the flow path resistance of the inflow path 32F is reduced to open the inflow path 32F.

The outflow amount changing unit 90 adjusts the outflow amount of the liquid LQ from the liquid chamber 31 under the control of the control unit 25. As will be described later, the outflow amount changing unit 90 adjusts the inflow amount of the liquid LQ from the liquid chamber 31 to the outflow passage 33F, thereby adjusting the pressure transmitted from the liquid chamber 31 to the outflow passage 33F. Functions as an adjustment unit.

The outflow amount changing unit 90 includes an additional outflow path 91, a drive chamber 93, a valve body 95, and a drive unit 96. The additional outflow passage 91 is a flow path of the liquid LQ connected to the outflow passage 33. In the head portion 20F of the sixth embodiment, the outflow passage 33 and the additional outflow passage 91 form an outflow passage 33F for discharging the liquid LQ from the liquid chamber 31.

The drive unit 96 and the valve body 95 of the outflow amount changing unit 90 have the same configuration as the drive unit 86 and the valve body 85 of the inflow amount changing unit 80. The drive chamber 93 is a room provided in the housing of the head portion 20F, and accommodates the drive portion 96. The drive chamber 93 is provided above the additional outflow passage 91. The drive chamber 93 and the additional outflow passage 91 are communicated with each other by a through hole 94 extending in a straight line.

The valve body 95 is arranged in the through hole 94 so that the tip portion thereof is exposed to the additional outflow path 91. A seal member is arranged in the through hole 94 as in the through hole 84 of the inflow amount changing portion 80 (not shown). It can be interpreted that the surface of the valve body 95 arranged in the outflow passage 33F constitutes a part of the inner wall surface of the outflow passage 33F.

In the outflow amount changing unit 90, the drive unit 96 connected to the rear end portion of the valve body 95 expands and contracts in the vertical direction to cause the valve body 95 to move up and down by a piston. In the outflow amount changing unit 90, the volume of the outflow passage 33F is reduced and the flow path resistance of the outflow passage 33F is increased by extending the drive unit 96. On the contrary, the contraction of the drive unit 96 increases the volume of the outflow path 33F and reduces the flow path resistance of the outflow path 33F.

In the sixth embodiment, the outflow passage 33F has a valve seat portion 92 similar to the valve seat portion 82 of the additional inflow passage 81. The valve seat portion 92 is provided at a position facing the tip end portion of the valve body 95 of the outflow amount changing portion 90. When the valve body 95 protrudes most into the additional outflow passage 91, its tip portion comes into contact with the inner wall surface of the valve seat portion 92 and closes the outflow passage 33F. In this way, the outflow amount changing unit 90 moves the valve body 95 in the direction in which the flow path resistance of the outflow path 33F increases, and closes the outflow path 33F. Further, the valve body 95 is moved in the direction in which the flow path resistance of the outflow path 33F is reduced to open the outflow path 33F.

FIG. 11 is a flow chart showing a control process in the discharge process executed by the control unit 25 in the liquid discharge device 100F. The control unit 25 controls the drive unit 45, the inflow amount changing unit 80 and the outflow amount changing unit 90, which are pressure transmission adjusting units, to execute a discharge process of discharging the liquid LQ from the nozzle 35. When starting the execution of the discharge process, the control unit 25 sets the drive unit 45 to the reference length described in the first embodiment, and adjusts the pressure of the liquid chamber 31 to a reference pressure equal to or lower than the meniscus withstand voltage.

Step 1 is a pressurizing step in which the transmission of pressure to the inflow path 32F, which is the flow path of the liquid LQ, is suppressed, the pressure in the liquid chamber 31 is increased, and the outflow of the liquid LQ is started from the nozzle 35. Is. In step 1, the control unit 25 executes the following pressurization process. In the pressurizing process, the control unit 25 first increases the flow path resistance of the inflow path 32F to the inflow amount changing unit 80 so that the pressure transmission from the liquid chamber 31 to the inflow path 32F is suppressed. .. The control unit 25 extends the drive unit 86 of the inflow amount changing unit 80, displaces the valve body 85 downward, and closes the inflow path 32F.

In the pressurizing process, the control unit 25 increases the flow path resistance of the outflow passage 33F to the outflow amount changing unit 90 so that the transmission of pressure from the liquid chamber 31 to the outflow passage 33F is suppressed. The control unit 25 extends the drive unit 96 of the outflow amount changing unit 90, displaces the valve body 95 downward, and closes the outflow path 33F. In the pressurizing process, at least the pressure transmission from the liquid chamber 31 to the inflow path 32F may be suppressed by the inflow amount changing section 80, and the outflow path 33F by the above-mentioned outflow amount changing section 90 may be suppressed. The blockage process may be omitted.

In the pressurizing process, the control unit 25 further compresses the elastic member 42 in the drive unit 45 to instantaneously displace the diaphragm 40, thereby reducing the volume of the liquid chamber 31 and reducing the volume of the liquid chamber 31. Increase pressure. As the pressure in the liquid chamber 31 increases, the outflow of the liquid LQ from the nozzle 35 is started.

In the pressurization process, as described above, the pressure transmission from the liquid chamber 31 to the inflow path 32F is suppressed, so that the pressure generated by the displacement of the diaphragm 40 escapes toward the inflow path 32F. It is suppressed that it ends up. Therefore, it is suppressed that the driving force for flowing out the liquid LQ from the nozzle 35 is suppressed, and the discharge efficiency of the liquid LQ from the nozzle 35 is improved. In the sixth embodiment, as described above, the pressure transmission from the liquid chamber 31 to the outflow passage 33F is also suppressed, so that the pressure generated in the liquid chamber 31 escapes to the outflow passage 33F. It is suppressed that it ends up. Therefore, the discharge efficiency of the liquid LQ from the nozzle 35 is further improved.

In step 2, after the outflow of the liquid LQ from the nozzle 35 is started by the pressurizing step, the pressure in the liquid chamber 31 is reduced while the liquid LQ is flowing out from the nozzle 35, so that the liquid in the nozzle 35 is discharged. This is a depressurizing step of separating the droplets from the LQ and causing them to fly. In step 2, the control unit 25 executes the following decompression process.

In the depressurization process, while the liquid LQ is flowing out from the nozzle 35, when a predetermined elapsed time elapses, the inflow amount changing unit 80, which is a pressure transmission adjusting unit, is driven to drive the liquid chamber 31. Reduce pressure. "While the liquid LQ is flowing out from the nozzle 35" means a state in which the liquid LQ hangs down from the discharge port 35o of the nozzle 35 so as to trail a tail. This period is a period in which the volume of the liquid chamber 31 is maintained in a state of being reduced from the initial volume by the drive unit 45, and the pressure of the liquid chamber 31 remains higher than before the execution of the pressurizing treatment. It is a period in.

During that period, the control unit 25 contracts the drive unit 86 of the inflow amount changing unit 80, displaces the valve body 85 upward, and opens the inflow path 32F. As a result, the volume of the inflow path 32F is increased, and the flow path resistance of the inflow path 32F is reduced. Therefore, the pressure is promoted to be released from the liquid chamber 31 to the inflow passage 32F, the pressure in the liquid chamber 31 is lowered, and a negative pressure acting in the direction of pulling the liquid LQ of the nozzle 35 toward the liquid chamber 31 is generated. This negative pressure promotes the separation of the droplet from the liquid LQ of the nozzle 35, and the flight of the droplet is started.

In the liquid discharge device 100F of the sixth embodiment, the depressurization process is executed by the drive unit 86 of the inflow amount changing unit 80, which is different from the drive unit 45 that executes the pressurization process. Therefore, even if the elapsed time after the execution of the pressurization process is shorter than the natural period of the drive unit 45, the execution of the depressurization process can be started. That is, it is possible to prevent the start timing of the decompression process from being affected by the operating performance of the drive unit 45. Therefore, a negative pressure for separating the droplets at a more suitable timing can be generated in the liquid chamber 31, and the controllability of the droplet ejection from the nozzle 35 is enhanced.

In the depressurization process, the volume of the liquid chamber 31 is increased by driving the drive unit 45 instead of or in addition to the operation of increasing the flow path resistance of the inflow path 32F by the inflow amount changing unit 80, so that the liquid is liquid. A negative pressure for separating the droplets may be generated in the chamber 31. Further, in the depressurization process, the outflow passage 33F is opened by driving the outflow amount changing unit 90, the outflow amount of the liquid LQ to the outflow passage 33F is increased, and the transmission of the pressure to the outflow passage 33F is promoted. A negative pressure may be generated in the chamber 31 to separate the droplets. In the depressurization process, the pressure in the liquid chamber 31 may be reduced so that the separation of the droplets from the nozzle 35 is promoted by driving at least one of the pressure transmission adjusting unit and the driving unit 45. As a result, a negative pressure for separating the droplets can be easily generated in the liquid chamber 31.

As described above, according to the liquid discharge device 100F of the sixth embodiment, since the head unit 20F includes the pressure transmission adjusting unit, the pressure change in the liquid chamber 31 is more efficient when the discharge process is executed. Can be caused to. Therefore, the discharge efficiency of the liquid LQ by the pressure treatment can be improved. In addition, the effect of separating the droplets by the decompression treatment can be enhanced, and the droplets can be prevented from trailing unnecessarily, the generation of unnecessary mist, and the shape of the droplets from being distorted. Therefore, deterioration of the flight state and the landing state of the droplet is suppressed, and the reliability of the liquid discharge by the head portion 20F is enhanced. In addition, according to the liquid discharge device 100F of the sixth embodiment, various effects described in the first embodiment can be obtained.

G. Seventh Embodiment:
FIG. 12 is a schematic cross-sectional view showing the configuration of the head portion 20G included in the liquid discharge device 100G of the seventh embodiment. In FIG. 12, the central axis CX indicating the central position of the diaphragm 40 is shown by a alternate long and short dash line. The configuration of the liquid discharge device 100G of the seventh embodiment is almost the same as the configuration of the liquid discharge device 100F of the sixth embodiment except that the head portion 20G of the seventh embodiment is provided instead of the head portion 20F. Is. The configuration of the head portion 20G of the seventh embodiment is almost the same as the configuration of the head portion 20F of the sixth embodiment except that the forming position of the nozzle 35 is different. The control unit 25 of the liquid discharge device 100G executes the discharge process described in the sixth embodiment (FIG. 11).

The inflow path 32 communicates with the liquid chamber 31 through the connection opening 32o that is open in the liquid chamber 31. Further, the outflow passage 33 communicates with the liquid chamber 31 through the connection opening 33o opened in the liquid chamber 31. The nozzle 35 communicates with the liquid chamber 31 through a communication port 39 opened at the bottom surface of the liquid chamber 31.

In the head portion 20G of the seventh embodiment, the communication port 39 of the nozzle 35 is provided at a position closer to the connection opening 32o side of the inflow path 32 than the center of the diaphragm 40. As a result, the pressure change generated in the inflow path 32F due to the operation of changing the volume of the inflow path 32F by the inflow amount changing unit 80 can easily reach the nozzle 35 of the liquid chamber 31. Therefore, in the depressurizing treatment for reducing the pressure in the liquid chamber 31 by driving the inflow amount changing unit 80 described in the sixth embodiment, the negative pressure for separating the droplets in the liquid chamber 31 is more efficiently applied. Can be caused. Therefore, the controllability of liquid discharge by the liquid discharge device 100G is further enhanced. In addition, according to the liquid discharge device 100G of the seventh embodiment, various effects similar to those described in the first embodiment and the sixth embodiment can be obtained.

H. Other embodiments:
The various configurations described in each of the above embodiments can be modified, for example, as follows. Each configuration of each of the other embodiments described below is positioned as an example of an embodiment for carrying out the invention, similarly to each of the above embodiments.

H1. Other Embodiment 1:
In each of the above embodiments, the drive unit 45 is composed of a piezo element. On the other hand, the drive unit 45 may be configured by an actuator other than the piezo element. The drive unit 45 may be configured by, for example, another actuator such as an air cylinder, a solenoid, or a magnetostrictive element. The same applies to the drive unit 86 of the inflow amount changing unit 80 and the drive unit 96 of the outflow amount changing unit 90 in the sixth embodiment and the seventh embodiment.

H2. Other Embodiment 2:
In each of the above embodiments, the fastening portions 50 and 50E may have a configuration other than the configuration including the pedestal portion 51, the support members 52 and 52E, the fastening screw 53, the pressing plate 54, and the adjusting screw 55. The fastening portions 50 and 50E may have, for example, a configuration in which the adjusting screw 55 and the pressing plate 54 functioning as the adjusting portions 70 and 70E are omitted. In this case, for example, the compression amount of each elastic member 42 may be adjusted by adjusting the distance between the support members 52 and 52E and the base portion 60 with the fastening screw 53. Further, the pedestal portion 51 may be omitted, and the support member 52 may be directly fastened to the head main body portions 30 and 30D. Alternatively, the support member 52 and the head main body portions 30 and 30D may have a configuration in which a wire-shaped member is wound and fastened while sandwiching the drive portion 45, the diaphragm 40, and the elastic member 42. The fastening portions 50 and 50E may be configured so as to be able to connect the drive portion 45 and the diaphragm 40 by applying a pressing force so that the elastic member 42 is in a compressed state.

H3. Other Embodiment 3:
The adjusting portions 70, 70E of each of the above embodiments may have a configuration other than the configuration in which the elastic member 42 is pressed by the adjusting screw 55 attached to the support members 52, 52E. The adjusting units 70, 70E may be configured by a stretchable mechanism such as a piezoelectric element, an airbag, or a jack arranged between the support members 52, 52E and the driving unit 45.

H4. Other Embodiment 4:
In each of the above embodiments, the elastic member 42 may not be composed of an annular resin member, or may be composed of another member having an elastic force. The elastic member 42 may be composed of, for example, a spring. Further, it may have a structure in which a plurality of elastic members are arranged around the liquid chamber 31. In the case of these configurations, a seal member that expands and contracts according to the displacement of the diaphragm 40 and forms a part of the wall portion of the liquid chamber 31 is arranged between the liquid chamber 31 and the elastic member. Will be done.

H5. Other Embodiment 5:
In each of the above embodiments, the head main body portions 30 and 30D have a configuration in which a plurality of laminated plates 30a to 30c are laminated. On the other hand, the head main body portions 30 and 30D do not have to have a configuration in which a plurality of laminated plates 30a to 30c are laminated. The head main body portions 30 and 30D may be manufactured, for example, by providing an internal space SP constituting the liquid chamber 31 inside the metal piece. In the fourth embodiment and the fifth embodiment described above, the head main body portion 30D may have a configuration in which each liquid chamber 31 is separated.

H6. Other Embodiment 6:
The spacer 72 of the second embodiment may not be composed of an annular member. The spacer 72 may be configured as a convex portion of the head main body portion 30 projecting toward the diaphragm 40 next to the elastic member 42. Alternatively, the spacer 72 may be configured as a convex portion protruding toward the head main body portion 30 at the outer peripheral end portion of the diaphragm 40.

H7. Other Embodiment 7:
The spacer 72 of the second embodiment and the other embodiment 4 and the inclined wall surface 75 of the third embodiment are the liquid discharge device 100D of the third embodiment, the fourth embodiment, the fifth embodiment, and the sixth embodiment. It may be applied to the head portion 20D to 20G of about 100G.

H8. Other Embodiment 8:
In the liquid discharge devices 100A to 100G of each of the above embodiments, a configuration may be applied in which the circulation path 18 is omitted and the liquid LQ is not circulated. For example, in the liquid discharge devices 100A to 100G of each of the above embodiments, a configuration may be applied in which the liquid LQ discharged through the outflow passage 33 of the head portions 20A to 20G is discharged to the outside as it is.

H9. Other Embodiment 9:
In the head portions 20A to 20G of the liquid discharge devices 100A to 100G of each of the above embodiments, the outflow path 33 may be omitted. The flow path of the liquid LQ in the head portions 20A to 20G may include at least the inflow path 32. In this case, the discharge passage 15, the liquid storage portion 16, the negative pressure generation source 17, and the circulation passage 18 are omitted, and the liquid LQ supplied to the head portions 20A to 20G through the supply passage 12 instead of the pressurizing pump 11. A pressure adjusting unit is provided to adjust the pressure of the above to a predetermined pressure. The pressure adjusting unit includes a pump that sucks the liquid LQ from the tank 10, a valve that opens and closes so that the pressure of the liquid chamber 31 of the head units 20A to 20G becomes a predetermined pressure, and the like.

H10. Other Embodiment 10:
In the liquid discharge devices 100A to 100G of each of the above embodiments, the compression amount of the elastic member 42 may not be adjusted according to the drive conditions of the drive unit 45. The compression amount of the elastic member 42 may be adjusted so as to obtain, for example, the displacement speed and the displacement amount of the target diaphragm 40.

H11. Other Embodiment 11:
In the sixth embodiment and the seventh embodiment, the configuration in which the head portions 20F and 20G have a plurality of liquid chambers 31 may be applied as in the fourth embodiment and the fifth embodiment. In this case, an inflow amount changing unit 80 or an outflow amount changing unit 90 may be provided for each liquid chamber 31.

H12. Other Embodiment 12:
In the sixth embodiment and the seventh embodiment described above, the pressurizing step of executing the pressurizing process may be omitted. In this case, instead of the pressurizing process described in the sixth embodiment, the drive unit 45 is not adjusted for pressure transmission to the flow paths 32F and 33F by the inflow amount changing unit 80 and the outflow amount changing unit 90. May be processed to increase the pressure in the liquid chamber 31. Further, in the sixth embodiment and the seventh embodiment, the decompression step of executing the depressurization treatment may be omitted. In the discharge process in this case, the droplets may be separated and flown by the inertial force generated in the liquid LQ flowing out from the nozzle 35 without generating a negative pressure in the liquid chamber 31.

H13. Other Embodiment 13:
In the sixth and seventh embodiments described above, the inflow amount changing unit 80 operates so as to open and close the inflow path 32F. The inflow amount changing unit 80 does not have to make the inflow path 32F completely closed or open. The inflow amount changing unit 80 may change the flow path resistance of the inflow path 32F by the operation of changing the volume of the inflow path 32F. In this case, the valve seat portion 82 of the inflow path 32F may be omitted. The same applies to the outflow amount changing portion 90 and the valve seat portion 92 thereof. In each of the above embodiments, the operation of changing the volume of the inflow path 32F by the inflow amount changing unit 80 can be interpreted as a configuration of changing the flow path cross-sectional area of the inflow path 32F. The same applies to the operation of changing the volume of the outflow path 33F by the outflow amount changing unit 90.

H14. Other Embodiment 14:
In the sixth and seventh embodiments, the inflow amount changing unit 80 displaces the valve body 85 by the driving unit 86 to change the volume of the inflow path 32F and change the flow path resistance of the inflow path 32F. ing. On the other hand, the inflow amount changing unit 80 may change the volume of the inflow path 32F and change the flow path resistance of the inflow path 32F according to the configuration different from the sixth embodiment and the seventh embodiment described above. good. For example, the inflow amount changing unit 80 may bend and deform the diaphragm forming a part of the inner wall surface of the inflow path 32F to change the volume of the inflow path 32F. Further, the inflow amount changing unit 80 may be configured to change the volume of the inflow path 32F by the shutter wall portion that moves across the inflow path 32F to change the flow path resistance of the inflow path 32F. A modification of the same configuration may be applied to the outflow amount changing unit 90.

H15. Other Embodiment 15:
In the liquid discharge device 100A of the first embodiment described above, the valve portion of the inflow path 32 and the outflow path 33 may be omitted. In the sixth and seventh embodiments described above, either one of the inflow amount changing unit 80 and the outflow amount changing unit 90, which are pressure transmission adjusting units, may be omitted.

H16. Other Embodiment 16:
The present invention is not limited to the liquid ejection device that ejects ink, but can be applied to any liquid ejection device that ejects a liquid other than ink. For example, the present invention can be applied to various liquid discharge devices such as the following.
(1) An image recording device such as a facsimile machine.
(2) A color material ejection device used for manufacturing a color filter for an image display device such as a liquid crystal display.
(3) An electrode material ejection device used for forming electrodes such as an organic EL (Electroluminescence) display and a surface emission display (Field Emission Display, FED).
(4) A liquid discharge device that discharges a liquid containing a bioorganic substance used for manufacturing a biochip.
(5) A sample ejection device as a precision pipette.
(6) Lubricating oil discharge device.
(7) Resin liquid discharge device.
(8) A liquid discharge device that pinpointly discharges lubricating oil to precision machines such as watches and cameras.
(9) A liquid ejection device that ejects a transparent resin liquid such as an ultraviolet curable resin liquid onto a substrate in order to form a micro hemispherical lens (optical lens) used for an optical communication element or the like.
(10) A liquid discharge device that discharges an acidic or alkaline etching solution for etching a substrate or the like.
(11) A liquid ejection device including a liquid ejection head that ejects another arbitrary minute amount of droplets.

As used herein, the term "liquid" may be any material that can be consumed by the liquid discharge device. For example, the "liquid" may be a material in a liquid state when the substance is in a liquid phase, and may be a material in a liquid state with high or low viscosity, and a sol, gel water, other inorganic solvent, organic solvent, solution, etc. Liquid materials such as liquid resins and liquid metals (metal melts) are also included in "liquid". Further, not only a liquid as a state of a substance but also a liquid in which particles of a functional material made of a solid substance such as a pigment or a metal particle are dissolved, dispersed or mixed in a solvent are included in the "liquid". Typical examples of liquids include ink and liquid crystal. Here, the ink includes general water-based inks, oil-based inks, and various liquid compositions such as gel inks and hot melt inks. Further, the “droplet” refers to a state of the liquid discharged from the liquid discharge device, and includes a granular, tear-like, and thread-like tail.

The present invention is not limited to each of the above-described embodiments, and can be realized with various configurations within a range not deviating from the gist thereof. For example, the technical features in the embodiments corresponding to the technical features in each embodiment described in the column of the outline of the invention are for solving a part or all of the above-mentioned problems, or one of the above-mentioned effects. It is possible to replace or combine as appropriate to achieve the part or all. In addition, the technical features are not limited to those described in the present specification as not essential, and if the technical features are not described as essential in the present specification, they may be appropriately deleted. Is possible.

10 ... tank, 11 ... pressurizing pump, 12 ... supply path, 15 ... discharge path, 16 ... liquid storage section, 17 ... negative pressure source, 18 ... circulation path, 20A ... head section, 20B ... head section, 20C ... Head unit, 20D ... Head unit, 20E ... Head unit, 20F ... Head unit, 20G ... Head unit, 25 ... Control unit, 30 ... Head body unit, 30D ... Head body unit, 30a ... First laminated plate, 30b ... First 2 laminated board, 30c ... 3rd laminated board, 31 ... liquid chamber, 31p ... through hole, 32 ... inflow path, 32F ... inflow path, 32o ... connection opening, 32s ... slit, 33 ... outflow path, 33F ... outflow path, 33o ... Connection opening, 33s ... Slit, 35 ... Nozzle, 35o ... Discharge port, 35t ... Tapered part, 36 ... Opening, 37 ... Inlet, 38 ... Outlet, 39 ... Communication port, 40 ... Vibrating plate, 42 ... Elastic member, 45 ... drive part, 50 ... fastening part, 50E ... fastening part, 51 ... pedestal part, 52 ... support member, 52E ... support member, 52p ... through hole, 52s ... adjustment screw hole, 53 ... fastening screw, 54 ... Press plate, 55 ... Adjustment screw, 60 ... Base, 61 ... Recess, 62 ... Opening, 63 ... First side wall, 64 ... Second side wall, 65 ... Screw hole, 70 ... Adjustment, 70E ... Individual Adjustment part, 72 ... Spacer, 75 ... Inclined wall surface, 80 ... Inflow amount changing part, 81 ... Additional inflow path, 82 ... Valve seat part, 83 ... Drive chamber, 84 ... Through hole, 85 ... Valve body, 86 ... Drive part , 90 ... Outflow amount changing part, 91 ... Additional outflow path, 92 ... Valve seat part, 93 ... Drive chamber, 94 ... Through hole, 95 ... Valve body, 96 ... Drive part, 100A ... Liquid discharge device, 100B ... Liquid discharge Device, 100C ... Liquid discharge device, 100D ... Liquid discharge device, 100E ... Liquid discharge device, 100F ... Liquid discharge device, 100G ... Liquid discharge device, LQ ... Liquid, SP ... Internal space

Claims (13)

It is a liquid discharge device
A head main body having a liquid chamber for accommodating a liquid and a nozzle for discharging the liquid in the liquid chamber.
The diaphragm that forms part of the wall of the liquid chamber,
An elastic member arranged between the diaphragm and the head body and supporting the diaphragm, and
A drive unit connected to the diaphragm, elastically deforming the elastic member to displace the diaphragm, and applying an external force to discharge the liquid from the nozzle to the diaphragm.
A fastening portion for fastening the drive portion, the diaphragm, and the head main body portion so as to support the diaphragm in a compressed state of the elastic member.
Equipped with
A liquid discharge device having a spacer between the diaphragm and the head body portion that limits compression of the elastic member. The liquid discharge device according to claim 1.
A liquid discharge device in which the amount of compression of the elastic member by the fastening portion is adjusted according to the driving conditions of the driving portion. The liquid discharge device according to claim 1 or 2.
The fastening portion is a liquid discharge device having an adjusting portion for adjusting the amount of compression of the elastic member. The liquid discharge device according to any one of claims 1 to 3.
The head main body portion has an inclined wall surface that surrounds the liquid chamber, is inclined downward toward the liquid chamber, and faces toward the diaphragm, below the diaphragm.
The elastic member is a liquid discharge device arranged between the inclined wall surface and the diaphragm. The liquid discharge device according to any one of claims 1 to 4.
The head main body portion has a plurality of the liquid chambers, and the head main body portion has a plurality of the liquid chambers.
The nozzle, the diaphragm, the drive unit, and the elastic member are provided one by one in each of the liquid chambers.
A liquid discharge device in which the head body portion, the plurality of diaphragms, the plurality of drive portions, and the plurality of elastic members are fastened by a common fastening portion. The liquid discharge device according to claim 5, which is subordinate to claim 3.
The fastening portion is a liquid discharge device having a plurality of individual adjusting portions for individually adjusting the compression amount of each of the elastic members as the adjusting portion. The liquid discharge device according to claim 5, which is subordinate to claim 3.
The fastening portion is a liquid discharge device having a common adjusting portion for adjusting the compression amount of each of the elastic members in common as the adjusting portion. The liquid discharge device according to any one of claims 1 to 7.
The head body is further
A flow path of the liquid connected to the liquid chamber, at least a flow path including an inflow path for supplying the liquid to the liquid chamber.
A pressure transmission adjusting unit that controls the inflow of the liquid from the liquid chamber to the flow path and adjusts the transmission of pressure from the liquid chamber to the flow path.
A liquid discharge device. The liquid discharge device according to claim 8.
A control unit that controls the drive unit and the pressure transmission adjusting unit to execute a discharge process for discharging the liquid from the nozzle is provided.
The control unit is used in the discharge process.
(I) In a state where the pressure transmission from the liquid chamber to the flow path is suppressed by the pressure transmission adjusting unit, the volume of the liquid chamber is reduced by the driving unit to increase the pressure of the liquid chamber. And the pressure treatment to start the outflow of the liquid from the nozzle,
(Ii) While the liquid is flowing out from the nozzle, when a predetermined elapsed time elapses, at least one of the pressure transmission adjusting unit and the driving unit is driven to drive the liquid chamber. A decompression process that reduces the pressure to separate droplets from the liquid in the nozzle and fly them.
A liquid discharge device that performs at least one of them. The liquid discharge device according to claim 8 or 9.
The pressure transmission adjusting unit is an inflow amount changing unit that changes the volume of the inflow passage to change the inflow amount of the liquid from the inflow passage to the liquid chamber.
The inflow path communicates with the liquid chamber through a connection opening that is open in the liquid chamber.
The nozzle communicates with the liquid chamber through a communication port opened in the liquid chamber, and the nozzle communicates with the liquid chamber.
The communication port is a liquid discharge device located on the connection opening side of the center of the diaphragm in the liquid chamber. The liquid discharge device according to any one of claims 1 to 7.
The head main body further includes an inflow path for allowing the liquid to flow into the liquid chamber and an outflow path for causing the liquid to flow out of the liquid chamber. The liquid discharge device according to any one of claims 8 to 10.
The flow path is a liquid discharge device including an outflow path through which the liquid in the liquid chamber is discharged. It is a manufacturing method of a liquid discharge device.
With respect to the head main body having the liquid chamber for accommodating the liquid and the nozzle for discharging the liquid in the liquid chamber, the vibrating plate forming a part of the wall portion of the liquid chamber is attached to the head main body. An elastic member is sandwiched between the two, a spacer that limits compression of the elastic member is arranged between the vibrating plate and the head body, and the elastic member is elastically deformed to form the vibrating plate. An assembly step of connecting a drive unit that is displaced and applies an external force for discharging the liquid from the nozzle to the vibrating plate to the vibrating plate.
A fastening step of fastening the drive unit, the diaphragm, and the head body portion so as to support the diaphragm in a compressed state of the elastic member.
Equipped with
The fastening step is a manufacturing method including a step of adjusting a compression amount of the elastic member.

Images