JP2010166672A - Diaphragm-type actuator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a diaphragm-type actuator that prevents a film member from being creep-deformed. <P>SOLUTION: The diaphragm-type actuator 1 includes a case 2 in which a film stretching opening 20 is opened, a plurality of electrode films 300, a dielectric-elastomer-made dielectric film 301 that is interposed between at least a pair of electrode films 300 of a plurality of electrode films 300 so as to expand/contract in the surface direction by changes in applied voltage between the pair of electrode films 300, a film member 3 for sealing the film stretching opening 20 while the peripheral edge is fixed to the rim of the film stretching opening 20, a biasing member 4 that applies a biasing force to the film member 3 in the driving direction intersecting with the surface direction of the film member 3, and a suppressing member 6 for suppressing at least a part of the biasing force applied to the film member 3. In a non-use state, the suppressing member 6 suppresses at least a part of the biasing force applied to the film member 3. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a diaphragm actuator that outputs a driving force or displacement using a film member that is electrostricted.

  For example, Patent Document 1 [FIG. 6] discloses a diaphragm pump using an electrostrictive membrane member. FIG. 13 is a sectional view in the axial direction of the diaphragm pump described in the document. As shown in FIG. 13, the diaphragm pump 100 described in the document includes a first case 101, a second case 102, a membrane member 103, and a coil spring 104. The membrane member 103 is interposed between the first case 101 and the second case 102. A pump chamber 105 is defined between the first case 101 and the membrane member 103. A spring chamber 106 is defined between the second case 102 and the membrane member 103. The coil spring 104 is accommodated in the spring chamber 106. The coil spring 104 is interposed between the inner surface of the bottom wall of the second case 102 and the membrane member 103.

  The film member 103 includes a pair of electrode films 103a and a dielectric film 103b. The dielectric film 103b is interposed between the pair of electrode films 103a. The membrane member 103 is urged toward the pump chamber 105 by a coil spring 104. When a voltage is applied between the pair of electrode films 103a, the dielectric film 103b, that is, the film member 103 is relaxed. The membrane member 103 bulges toward the pump chamber 105 by the biasing force of the coil spring 104 according to the amount of relaxation. For this reason, the volume of the pump chamber 105 decreases. Therefore, the fluid in the pump chamber 105 is sent out to the outside. When the application of the voltage is released, the membrane member 103 contracts by its own elastic restoring force against the urging force of the coil spring 104. For this reason, the volume of the pump chamber 105 increases. Therefore, fluid flows into the pump chamber from the outside. As described above, the diaphragm pump 100 described in this document increases or decreases the volume of the pump chamber 105 by deforming the membrane member 103. That is, the fluid is pumped.

JP 2001-286162 A

  However, according to the diaphragm pump 100 described in the document, a biasing force is always applied from the coil spring 104 to the membrane member 103. For this reason, there exists a possibility that the film | membrane member 103 may carry out creep deformation. That is, when the urging force of the coil spring 104 continues to be applied for a long time, the membrane member 103 may be distorted over time. When the film member 103 creep-deforms, the film thickness of the dielectric film 103b is reduced accordingly. For this reason, when a voltage is applied between the pair of electrode films 103a, the pair of electrode films 103a is likely to be conducted through the dielectric film 103b.

  The diaphragm actuator of the present invention has been completed in view of the above problems. Accordingly, an object of the present invention is to provide a diaphragm actuator in which the membrane member is not easily creep-deformed.

  (1) In order to solve the above-described problem, the diaphragm actuator of the present invention includes a case in which a film extending opening is opened, a plurality of electrode films, and a gap between at least a pair of the electrode films. And a dielectric film made of a dielectric elastomer that expands and contracts in a plane direction by a change in applied voltage between the pair of electrode films, and a peripheral edge portion is fixed to a rim portion of the film stretching opening. And a biasing member capable of applying a biasing force to the membrane member in a driving direction intersecting the surface direction of the membrane member. A suppression member capable of suppressing at least a part of the urging force applied to the membrane member, and a non-use state, a low voltage state, and a high voltage state in which the applied voltage is higher than the low voltage state In the use state that can be switched to, and in the non-use state The suppressing member suppresses at least a part of the urging force applied to the membrane member. In the use state, the suppressing member releases the urging force applied to the membrane member, and In the voltage state, the urging force is applied to the membrane member. In the high voltage state, the membrane member tries to expand in the surface direction with the peripheral edge portion being fixed to the mouth edge portion. The membrane member is relaxed, and the membrane member is deformed in the driving direction by the biasing force according to the amount of relaxation of the membrane member (corresponding to claim 1).

  The diaphragm actuator of the present invention can be switched between a non-use state in which it is stopped and a use state in use. In the unused state, the suppressing member suppresses at least a part of the urging force applied from the urging member to the membrane member. For this reason, the urging | biasing force added to a film | membrane member becomes small compared with the case where there is no suppression member. Therefore, the membrane member is not easily creep-deformed. In other words, it is difficult for the dielectric film to be thin. Therefore, in a use state, particularly in a high voltage state, it is difficult for the pair of electrode films to conduct through the dielectric film. Further, since the film member is not easily creep-deformed, the amount of displacement of the film member in the driving direction when switching between the low voltage state and the high voltage state is difficult to decrease.

  (1-1) Preferably, in the configuration of the above (1), the membrane member is stretched at a stretch rate of 10% or more and 600% or less at the membrane stretching port. Stretch ratio is stretch ratio (%) = {√ (S / S0) −1} × 100 (S0: area of the film member before stretching (natural state = no load state), S: area of the film member after stretching. ). When the membrane member is stretched in the stretched state, the amount of displacement of the membrane member in the driving direction when switching between the low voltage state and the high voltage state increases. In addition, the voltage resistance is improved. On the other hand, when there is no suppression member, when the membrane member is stretched in the stretched state, the membrane member is likely to be creep-deformed by the urging force of the urging member.

  In this respect, according to the present configuration, the suppressing member suppresses at least a part of the urging force applied from the urging member to the membrane member in the non-use state. For this reason, the film member is not easily creep-deformed. Therefore, according to this configuration, the displacement amount of the membrane member can be increased, the voltage resistance can be improved, and creep deformation of the membrane member can be suppressed.

  Here, the reason why the stretching ratio is set to 10% or more is that when it is less than 10%, the amount of displacement of the membrane member becomes small. Moreover, it is because a withstand voltage property falls. On the other hand, the reason why the stretching ratio is set to 600% or less is that when it exceeds 600%, the membrane member tends to deteriorate. More preferably, the stretching ratio is 50% or more and 300% or less. When the stretching ratio is 50% or more, it is easy to ensure a desired amount of displacement of the membrane member. Moreover, it is easy to ensure desired voltage resistance. When the stretching ratio is 300% or less, the membrane member is not easily deteriorated.

  (2) Preferably, in the configuration of the above (1), the suppression member includes a sealing case in which a sealing port is provided in the membrane extending port through the membrane member, and the sealing member A pressure adjusting member capable of adjusting the internal pressure of the case, and canceling at least a part of the urging force applied to the film member by adjusting the internal pressure in the non-use state. It is better to have a configuration (corresponding to claim 2).

  The membrane member is interposed between a membrane extending port, that is, a case, and a sealing port, that is, a sealing case. For example, when an urging force is applied to the membrane member in a direction in which the film member bulges toward the sealing case, the internal pressure of the sealing case in the unused state is made higher than the internal pressure of the sealing case in the low voltage state. Further, for example, when an urging force is applied to the membrane member in the direction in which the film member bulges, the internal pressure of the sealing case in the unused state is made lower than the internal pressure of the sealing case in the low voltage state. According to this configuration, at least part of the urging force can be offset by adjusting the internal pressure of the sealing case. For this reason, creep deformation of the membrane member can be suppressed.

  (3) Preferably, in the configuration of (1), the urging member applies the urging force to one surface of the membrane member, and the suppression member faces away from the one surface of the membrane member. A counter member capable of applying a counter biasing force in a direction opposite to the biasing force to the surface, and canceling at least a part of the biasing force by the counter biasing force in the non-use state. It is better to have a configuration (corresponding to claim 3).

  For example, when an urging force is applied to the membrane member in a direction to bulge outward from the case, an anti-urging force is applied to the membrane member in a direction to bulge inward from the case when not in use. Further, for example, when a biasing force is applied to the membrane member in a direction in which the membrane member bulges inside the case, an anti-biasing force is applied to the membrane member in a direction in which the membrane member bulges outside the case. According to this configuration, at least a part of the urging force can be canceled by applying a counter urging force from the opposite direction to the urging force. For this reason, creep deformation of the membrane member can be suppressed.

  (4) Preferably, in any one of the configurations (1) to (3), the biasing member is a coil spring (corresponding to claim 4). According to this configuration, the biasing force applied to the membrane member can be set to a desired value by appropriately adjusting the spring constant, total length, diameter, pitch, and the like of the coil spring.

  (5) Preferably, in the configuration of any one of the above (1) to (4), further connected to the membrane member so as to be able to transmit power, and can reciprocate in the driving direction according to deformation of the membrane member. It is better to have a structure having a simple output member (corresponding to claim 5). According to this structure, a driving force and a displacement can be output outside via an output member.

  (6) Preferably, in the configuration of the above (5), the case further includes a bottom wall portion facing the extension opening and having an output hole formed therein, and the output member includes the membrane A flange portion that comes into contact with the member, and a rod portion that protrudes from the flange portion and is reciprocally inserted into the output hole and has an engaged portion on the outer peripheral surface, and the biasing member includes: An elastically compressed state is interposed between the flange portion and the bottom wall portion, and the suppression member is a lock member that can be engaged with and disengaged from the engaged portion. In use, the lock member is engaged with the engaged portion to restrict the movement of the rod portion, and at least a part of the urging force applied to the membrane member through the flange portion is blocked. It is better to have a configuration (corresponding to claim 6).

  According to this configuration, the flange portion is in contact with the membrane member. In addition, the biasing member is interposed between the flange portion and the bottom wall portion in an elastically compressed state. For this reason, when there is no lock member, a biasing force is applied from the biasing member to the membrane member via the flange portion in the direction of pressing the membrane member. In this regard, according to the present configuration, the locking member is engaged with the engaged portion of the rod portion when not in use. For this reason, the movement of the rod portion, that is, the flange portion when not in use is restricted. Therefore, at least a part of the urging force applied to the membrane member can be blocked.

  (7) Preferably, in any one of the configurations (1) to (4), the case further includes a pump chamber whose volume changes according to deformation of the membrane member, and a volume change of the pump chamber. Accordingly, it is preferable to have a configuration including an inflow port for allowing fluid to flow into the pump chamber from the outside and an outflow port for allowing fluid to flow out of the pump chamber according to a change in volume of the pump chamber. 7).

  That is, this structure uses the diaphragm type actuator of the present invention as a diaphragm type pump. According to this structure, fluid can be pumped by the volume change of the pump chamber.

  According to the present invention, it is possible to provide a diaphragm actuator in which the membrane member is not easily creep-deformed.

It is an axial sectional view in the non-use state of the diaphragm type actuator of a first embodiment. It is a perspective view of the same diaphragm type actuator. It is a disassembled perspective view of the same diaphragm type actuator. It is a disassembled perspective view of the expansion-contraction film | membrane of a film | membrane member. It is an enlarged view in the frame V of FIG. It is an axial sectional view in the low voltage state of the diaphragm type actuator. It is an axial sectional view in the high voltage state of the diaphragm type actuator. It is an axial direction sectional view in the state of non-use of the diaphragm type actuator of a second embodiment. It is an axial sectional view in the low voltage state of the diaphragm type actuator. It is an axial direction sectional view in the state of non-use of the diaphragm type actuator of a third embodiment. It is an axial sectional view in the low voltage state of the diaphragm type actuator. It is an axial sectional view in a non-use state of a diaphragm type actuator of a fourth embodiment. It is an axial sectional view of a conventional diaphragm pump.

  Embodiments of the diaphragm type actuator of the present invention will be described below.

<First embodiment>
[Configuration of diaphragm actuator]
First, the structure of the diaphragm type actuator 1 of this embodiment is demonstrated. FIG. 1 is a sectional view in the axial direction of the diaphragm type actuator according to the present embodiment when not in use. FIG. 2 shows a perspective view of the diaphragm actuator. FIG. 3 shows an exploded perspective view of the diaphragm actuator. As shown in FIGS. 1 to 3, the diaphragm actuator 1 of the present embodiment includes a case 2, a membrane member 3, a coil spring 4, an output member 5, a pressure adjusting member 6, and four spacers 7. It is equipped with.

(Case 2)
The case 2 is made of resin and has a bottomed cylindrical shape (cup shape) that opens upward. The case 2 includes a membrane extending opening 20, a bottom wall portion 21, a flange portion 22, and a membrane fixing groove 23. An output hole 210 is formed in the bottom wall portion 21. The flange portion 22 has a ring shape. The flange portion 22 is provided around the outer peripheral surface of the case 2. The flange portion 22 projects outward in the radial direction from the outer peripheral surface of the case 2. Bolt fixing holes 220 are formed in the flange portion 22. A total of four bolt fixing holes 220 are arranged every 90 ° in the circumferential direction of the flange portion 22. The film stretching port 20 is disposed at the upper end opening of the case 2. The film stretching port 20 and the bottom wall portion 21 face each other in the vertical direction. The membrane fixing groove 23 is provided around the outer peripheral surface of the case 2. The membrane fixing groove 23 is disposed above the flange portion 22.

(Membrane member 3)
The film member 3 includes an upper stretch film 30 and a lower insulating film 31. The membrane member 3 is stretched at a membrane tension opening 20 of the case 2 with a predetermined tension (stretching rate 100%). The peripheral edge of the membrane member 3 is clamped by the clamp ring 32 from the outside in the radial direction while entering the membrane fixing groove 23 of the case 2.

  A laminated structure of the film member 3 will be described. FIG. 4 shows an exploded perspective view of the stretchable membrane of the membrane member. FIG. 5 shows an enlarged view in the frame V of FIG. As shown in FIGS. 4 and 5, the stretchable film 30 includes a six-layer electrode film 300 and a five-layer dielectric film 301. The six-layer electrode films 300 and the five-layer dielectric films 301 are alternately stacked in the vertical direction so that the electrode films 300 are the uppermost layer and the lowermost layer. The electrode film 300 is made of acrylic rubber in which conductive carbon black is dispersed, and has a circular thin film shape. The electrode film 300 can be expanded and contracted so as not to restrict the expansion and contraction of the dielectric film 301. Of the six-layer electrode film 300, the three-layer electrode film 300 is connected to the positive side of the power supply via the switch S. Of the six-layer electrode films 300, the remaining three-layer electrode films 300 are connected to the negative side of the power source. The plus-side electrode film 300 and the minus-side electrode film 300 are adjacent to each other in the vertical direction with the dielectric film 301 interposed therebetween. The dielectric film 301 is made of nitrile rubber and has a circular thin film shape. The dielectric film 301 has a larger diameter than the electrode film 300. The insulating film 31 is made of nitrile rubber and has a circular thin film shape. The insulating film 31 is disposed on the lower surface of the lowermost electrode film 300. The insulating film 31 can be expanded and contracted so as not to restrict the expansion and contraction of the elastic film 30.

(Output member 5)
The output member 5 is made of resin and has a nail shape as a whole. That is, the output member 5 includes a flange portion 50 and a rod portion 51. The flange portion 50 has a disk shape. The flange portion 50 is in contact with the lower surface of the film member 3, that is, the lower surface of the insulating film 31. The rod portion 51 has a cylindrical shape. The rod portion 51 protrudes downward from the approximate center of the lower surface of the flange portion 50. The rod portion 51 is inserted into the output hole 210 of the bottom wall portion 21 of the case 2 so as to be movable up and down (reciprocating). The lower end of the rod portion 51 is connected to the driven member 90.

(Coil spring 4)
The coil spring 4 is made of metal and is wrapped around the rod portion 51. The coil spring 4 is interposed between the lower surface of the flange portion 50 and the upper surface of the bottom wall portion 21 in an elastically compressed state. The coil spring 4 applies an upward biasing force to the membrane member 3 via the flange portion 50.

(Pressure adjusting member 6)
The pressure adjusting member 6 includes a sealing case 60 and a gas supply device 61. The gas supply device 61 is included in the pressure adjusting unit of the present invention. The sealing case 60 is made of resin and has a bottomed cylindrical shape (cup shape) that opens downward. The sealing case 60 is disposed above the case 2 and the membrane member 3. The sealing case 60 includes a sealing port 600, an upper bottom wall portion 601, and a flange portion 602. A gas supply hole 601a is formed in the upper bottom wall portion 601. The sealing port 600 is disposed in the lower end opening of the sealing case 60. The sealing port 600 and the upper bottom wall portion 601 are opposed to each other in the vertical direction. The sealing port 600 is laid down on the membrane tensioning port 20 via the membrane member 3. The flange portion 602 has a ring shape. The flange portion 602 is provided around the outer peripheral surface of the sealing case 60. The flange portion 602 projects radially outward from the edge portion of the sealing port 600. A bolt insertion hole 602 a is formed in the flange portion 602. A total of four bolt insertion holes 602a are arranged every 90 ° in the circumferential direction of the flange portion 602. The four bolt insertion holes 602a and the four bolt fixing holes 220 face each other in the vertical direction. The four bolts 62 pass through the four bolt insertion holes 602a from the upper side to the lower side, and are fixed to the four bolt fixing holes 220. That is, the sealing case 60 is fixed to the case 2 by the four bolts 62.

  The gas supply device 61 is connected to the gas supply hole 601a. The gas supply device 61 can adjust the internal pressure of the sealing case 60. Specifically, the gas supply device 61 can increase the internal pressure of the sealing case 60 by increasing the amount of air inside the sealing case 60. Further, the gas supply device 61 can reduce the internal pressure of the sealing case 60 by reducing the amount of air inside the sealing case 60.

(Spacer 7)
Each of the four spacers 7 is made of resin and has a cylindrical shape. The four spacers 7 are mounted around the outer peripheral surface of the four bolts 62 between the pair of upper and lower flange portions 602 and 22. The total length of the four spacers 7 in the axial direction (vertical direction) is the same. By disposing the four spacers 7, the sealing case 60 can be fixed to the case 2 in a state where the pair of upper and lower flange portions 602 and 22 are substantially parallel to each other.

[Diaphragm actuator movement]
Next, the movement of the diaphragm actuator 1 of this embodiment will be described. The diaphragm actuator 1 can be switched between a non-use state and a use state. In addition, the diaphragm actuator 1 can be switched between a low voltage state and a high voltage state in use.

(Motion when switching from non-use state to use state (low voltage state))
The non-use state refers to a state where the diaphragm actuator 1 is not used. For example, it means a state where the main power supply is stopped. In an unused state, the urging force of the coil spring 4 is applied to the membrane member 3 from below. On the other hand, the internal pressure of the sealing case 60 is applied to the membrane member 3 from above. The membrane member 3 is in a substantially planar state by balancing the loads acting from above and below, as represented by these urging forces and internal pressures (including the urging force and internal pressure, as well as the weight of the membrane member 3). That is, the state which is not elastically deformed up and down is maintained.

  FIG. 6 is a sectional view in the axial direction of the diaphragm actuator according to the present embodiment in a low voltage state. When switching from a non-use state to a low voltage state, the internal pressure of the sealing case 60 is reduced until it becomes substantially atmospheric pressure. That is, the air inside the sealing case 60 is leaked. When the internal pressure of the sealing case 60 decreases, the balance position of the load that acts on the membrane member 3 from the vertical direction is shifted upward. For this reason, when the non-use state is switched to the low voltage state, the membrane member 3 bulges upward by a slight amount. In the low voltage state, the urging force of the coil spring 4 is applied to the membrane member 3 from below. On the other hand, the elastic restoring force of the membrane member 3 acts on the membrane member 3 in the direction of returning to the substantially planar state shown in FIG.

(Motion when switching from a low voltage state to a high voltage state)
FIG. 7 is a sectional view in the axial direction of the diaphragm actuator of the present embodiment in a high voltage state. When switching from the low voltage state shown in FIG. 6 to the high voltage state shown in FIG. 7, the switch S shown in FIG. 4 is closed. When the switch S is closed, a voltage is applied between the positive-side three-layer electrode film 300 and the negative-side three-layer electrode film 300. For this reason, an electrostatic attractive force is generated between a pair of electrode films 300 adjacent in the vertical direction via the dielectric film 301. Due to the electrostatic attractive force, the dielectric film 301 is compressed in the vertical direction (film thickness direction). In addition, the dielectric film 301 tends to expand in the radial direction (plane direction) by the amount compressed. Here, the peripheral edge portion of the dielectric film 301 (that is, the film member 3) is fixed by the clamp ring 32. For this reason, the dielectric film 301 cannot relax in the radial direction and relaxes. Following the dielectric film 301, the electrode film 300 and the insulating film 31 also relax. Accordingly, the entire membrane member 3 is relaxed.

  In the low voltage state shown in FIG. 6, the membrane member 3 and the output member 5 are urged upward by the coil spring 4. Due to the urging force, the membrane member 3 bulges upward as shown in FIG. Further, the output member 5 moves upward. When the output member 5 moves upward, the driven member 90 also moves upward accordingly. Thus, when the low voltage state is switched to the high voltage state, the driven member 90 can be raised.

(Motion when switching from high voltage state to low voltage state)
When switching from the high voltage state to the low voltage state, the switch S shown in FIG. 4 is opened. When the switch S is opened, the applied voltage between the positive three-layer electrode film 300 and the negative three-layer electrode film 300 is released. For this reason, the electrostatic attractive force between the pair of electrode films 300 adjacent in the vertical direction via the dielectric film 301 is released. Therefore, the dielectric film 301 contracts in the radial direction and expands in the vertical direction while resisting the biasing force of the coil spring 4 by its own elastic restoring force. Following the dielectric film 301, the electrode film 300 and the insulating film 31 also contract in the radial direction and expand in the vertical direction while resisting the urging force of the coil spring 4 due to their elastic restoring force. Therefore, the entire membrane member 3 contracts in the radial direction and expands in the vertical direction. The membrane member 3 moves backward to the state shown in FIG. 6 (a state in which the membrane member 3 bulges slightly upward). That is, the membrane member 3 is displaced downward. Therefore, the output member 5 moves downward. When the output member 5 moves downward, the driven member 90 also moves downward accordingly. Thus, when the high voltage state is switched to the low voltage state, the driven member 90 can be lowered.

(Motion when switching from the use state (low voltage state) to the non-use state)
When switching from the low voltage state to the non-use state, the internal pressure of the sealing case 60 is increased. That is, air is pumped into the sealing case 60 by the gas supply device 61. When the internal pressure of the sealing case 60 increases, the balance position of the load acting on the membrane member 3 from above and below is shifted downward. Therefore, when switching from the low voltage state to the non-use state, as shown in FIG. 1, the membrane member 3 moves back to a substantially flat state, that is, a state where it is not elastically deformed in the vertical direction.

[Function and effect]
Next, the effect of the diaphragm type actuator 1 of this embodiment is demonstrated. The diaphragm actuator 1 of this embodiment can be switched between a non-use state and a use state. In the non-use state, the pressure adjusting member 6 cancels out almost all the urging force applied from the coil spring 4 to the membrane member 3. For this reason, the urging force applied to the membrane member 3 is extremely small as compared with the case where the pressure regulating member 6 is not provided. Accordingly, the membrane member 3 is not easily creep-deformed. In other words, the dielectric film 301 is unlikely to be thin. Therefore, the plus-side electrode film 300 and the minus-side electrode film 300 are less likely to conduct through the dielectric film 301 in a use state, particularly in a high voltage state. In addition, since the film member 3 is not easily creep-deformed, the amount of displacement of the film member 3 in the vertical direction (driving direction) when switching between the low voltage state and the high voltage state is difficult to decrease. The membrane member 3 is stretched at a stretch rate of 100% in the membrane stretching port 20 of the case 2. For this reason, the displacement amount of the membrane member 3 in the vertical direction, that is, the displacement amount of the driven member 90 can be set large. In addition, the dielectric strength of the dielectric film 301 is increased.

  Further, according to the diaphragm actuator 1 of the present embodiment, substantially all of the urging force applied from the coil spring 4 to the membrane member 3 can be canceled only by adjusting the internal pressure of the sealing case 60. For this reason, the structure of the diaphragm actuator 1 is simplified.

  Moreover, according to the diaphragm type actuator 1 of this embodiment, the coil spring 4 is used as an urging member. For this reason, the biasing force applied to the membrane member 3 can be set to a desired value by appropriately adjusting the spring constant, total length, diameter, pitch, and the like of the coil spring 4.

<Second embodiment>
The difference between the diaphragm actuator of the present embodiment and the diaphragm actuator of the first embodiment is that a solenoid is arranged instead of the pressure regulating member. Therefore, only the differences will be described here.

  FIG. 8 shows an axial cross-sectional view of the diaphragm type actuator according to this embodiment in a non-use state. In addition, about the site | part corresponding to FIG. 1, it shows with the same code | symbol. FIG. 9 is a sectional view in the axial direction of the diaphragm actuator in a low voltage state. In addition, about the site | part corresponding to FIG. 6, it shows with the same code | symbol.

  As shown in FIGS. 8 and 9, the diaphragm actuator 1 of this embodiment includes a solenoid 80. The solenoid 80 is included in the counter member of the present invention. The solenoid 80 includes a case 800 and a shaft 801. The case 800 includes a coil (not shown). The shaft 801 includes a flange portion 801a and a rod portion 801b. The flange portion 801a has a disk shape. In the non-use state shown in FIG. 8, the flange portion 801 a is in contact with the upper surface of the membrane member 3, that is, the upper surface of the stretchable membrane 30. The flange portion 801a and the flange portion 50 of the output member 5 face each other in the vertical direction with the membrane member 3 interposed therebetween. The area of the lower surface of the flange portion 801a and the area of the upper surface of the flange portion 50 are substantially the same. The rod portion 801b has a cylindrical shape. The rod portion 801b protrudes upward from the approximate center of the upper surface of the flange portion 801a. The rod portion 801b is inserted inside the case 800 in the radial direction of the coil so as to be movable up and down (reciprocating). The shaft 801 can be driven by passing a current through the coil.

  In the non-use state shown in FIG. 8, the urging force of the coil spring 4 is applied to the membrane member 3 from below. On the other hand, the counter biasing force of the shaft 801 is applied to the membrane member 3 from above. As represented by these urging forces and counter-biasing forces, the membrane member 3 is balanced by a load acting from above and below (including not only the urging force and counter-biasing force but also the weight of the membrane member 3). A substantially flat state, that is, a state in which it is not elastically deformed in the vertical direction is maintained.

  When switching from the unused state to the low voltage state shown in FIG. 9, the shaft 801 is raised to remove the counter-biasing force from the membrane member 3. When the counter-biasing force disappears, the balance position of the load acting on the membrane member 3 from above and below is shifted upward. For this reason, when the non-use state is switched to the low voltage state, the membrane member 3 bulges upward by a slight amount. In the low voltage state, the urging force of the coil spring 4 is applied to the membrane member 3 from below. On the other hand, the elastic restoring force possessed by itself is acting on the membrane member 3 in the direction of returning to the substantially planar state shown in FIG.

  The diaphragm actuator 1 according to the present embodiment and the diaphragm actuator according to the first embodiment have the same functions and effects with respect to parts having the same configuration. Further, in the membrane member 3, the urging force from the coil spring 4 concentrates at a portion where the flange portion 50 of the output member 5 contacts. In this regard, according to the diaphragm actuator 1 of the present embodiment, the flange portion 801a of the solenoid 80 and the flange portion 50 of the output member 5 face each other in the vertical direction with the membrane member 3 interposed therebetween. In addition, the area of the lower surface of the flange portion 801a and the area of the upper surface of the flange portion 50 are substantially the same. For this reason, the counter-biasing force can be accurately applied to the portion where the biasing force from the coil spring 4 is concentrated.

  Moreover, according to the diaphragm type actuator 1 of this embodiment, a pressure regulation member is unnecessary. For this reason, piping etc. for supplying gas are unnecessary. Therefore, the diaphragm type actuator 1 can be reduced in size.

<Third embodiment>
The difference between the diaphragm actuator of the present embodiment and the diaphragm actuator of the second embodiment is that a lock member is disposed instead of the solenoid. Therefore, only the differences will be described here.

  FIG. 10 is a cross-sectional view in the axial direction when the diaphragm actuator according to this embodiment is not used. In addition, about the site | part corresponding to FIG. 8, it shows with the same code | symbol. FIG. 11 is a sectional view in the axial direction of the diaphragm actuator in a low voltage state. In addition, about the site | part corresponding to FIG. 9, it shows with the same code | symbol.

  As shown in FIGS. 10 and 11, the diaphragm actuator 1 of this embodiment includes a lock member 81. An engaged hole 510 is formed in the rod portion 51 of the output member 5. The engaged hole 510 is included in the engaged portion of the present invention. The engaged hole 510 penetrates the rod portion 51 in the diameter direction (horizontal direction). The lock member 81 can be engaged and disengaged with respect to the engaged hole 510.

  In the non-use state shown in FIG. 10, the lock member 81 is locked in the engaged hole 510. The lock member 81 is hooked on the bottom surface of the bottom wall portion 21. For this reason, the rod part 51, ie, the output member 5, cannot raise. Therefore, the membrane member 3 and the output member 5 are not in contact. The film member 3 maintains a substantially planar state, that is, a state in which it is not elastically deformed in the vertical direction.

  When switching from the unused state to the low voltage state shown in FIG. 11, the lock member 81 is extracted from the engaged hole 510. When the lock member 81 is extracted, the output member 5 is raised by the urging force of the coil spring 4. The flange portion 50 pushes up the lower surface of the membrane member 3. For this reason, when the non-use state is switched to the low voltage state, the membrane member 3 bulges upward by a slight amount. In the low voltage state, the urging force of the coil spring 4 is applied to the membrane member 3 from below. On the other hand, the elastic restoring force of the membrane member 3 acts on the membrane member 3 in the direction of returning to the substantially planar state shown in FIG.

  The diaphragm actuator 1 according to the present embodiment and the diaphragm actuator according to the second embodiment have the same functions and effects with respect to parts having the same configuration. Further, according to the diaphragm actuator 1 of the present embodiment, there is no possibility that the membrane member 3 is compressed from above and below in the unused state. That is, there are mainly two loads acting on the membrane member 3 in a non-use state: a tensioning force on the membrane tensioning port 20 and a weight of the membrane member 3. For this reason, the creep deformation of the membrane member 3 can be further suppressed. Moreover, it is not necessary to arrange another member above the membrane member 3. For this reason, the diaphragm type actuator 1 can be reduced in size.

<Fourth embodiment>
The difference between the diaphragm actuator of the present embodiment and the diaphragm actuator of the first embodiment is that the diaphragm actuator is used as a diaphragm pump. Further, the coil spring is housed in the sealing case. Therefore, only the differences will be described here.

  FIG. 12 is a sectional view in the axial direction of the diaphragm actuator according to the present embodiment when not in use. In addition, about the site | part corresponding to FIG. 1, it shows with the same code | symbol. As shown in FIG. 12, a spring seat member 82 is disposed on the upper surface of the membrane member 3. The spring seat member 82 includes a bottom wall portion 820 and a convex portion 821. The bottom wall portion 820 has a disk shape. The bottom wall portion 820 is disposed on the upper surface of the membrane member 3. The convex portion 821 has a short-axis cylindrical shape. The convex portion 821 protrudes upward from the approximate center of the upper surface of the bottom wall portion 820. On the other hand, a spring seat 601 b is formed around the gas suction hole 601 c of the upper bottom wall portion 601 of the sealing case 60. The spring seat 601b has a ring rib shape. The spring seat 601b and the spring seat member 82 face each other in the vertical direction. The coil spring 4 is interposed between the spring seat 601 b and the spring seat member 82. The coil spring 4 urges the membrane member 3 downward via a spring seat member 82. The gas suction device 64 is connected to the gas suction hole 601c. The gas suction device 64 can depressurize the inside of the sealing case 60. The gas suction device 64 is included in the pressure adjusting unit of the present invention.

  A pump chamber 25 is defined inside the case 2. An inflow port 211 a and an outflow port 211 b are opened in the bottom wall portion 21 of the case 2. The inflow port 211a, the pump chamber 25, and the outflow port 211b are in communication. A check valve (not shown) is disposed upstream of the inflow port 211a. A check valve (not shown) is disposed on the downstream side of the outlet 211b. The two check valves can be opened only in the direction in which fluid flows from the upstream side to the downstream side.

  In an unused state, the urging force of the coil spring 4 is applied to the membrane member 3 from above. In addition, the membrane member 3 is sucked by the gas suction device 64 from above. That is, the membrane member 3 is pressed and sucked from above. In a non-use state, the membrane member 3 maintains a substantially planar state, that is, a state in which it is not elastically deformed in the up-down direction.

  When switching from the non-use state to the low voltage state, the internal pressure of the sealing case 60 is increased until the pressure becomes approximately atmospheric pressure. When the internal pressure of the sealing case 60 increases, the membrane member 3 bulges out by a slight amount due to the urging force of the coil spring 4 as shown by the dotted line A in FIG. In the low voltage state, the urging force of the coil spring 4 is applied to the membrane member 3 from above. On the other hand, the elastic restoring force possessed by itself is acting on the membrane member 3 in the direction of returning to the substantially planar state shown in FIG.

  When switching from the low voltage state to the high voltage state, a voltage is applied to the membrane member 3 to relax the membrane member 3. The membrane member 3 bulges downward as indicated by a dotted line B in FIG. When the membrane member 3 is displaced from the dotted line A state to the dotted line B state, the volume of the pump chamber 25 is reduced accordingly. For this reason, the fluid is pumped from the outlet 211b to the outside.

  When switching from the high voltage state to the low voltage state, the voltage applied to the membrane member 3 is released and the membrane member 3 is contracted. The membrane member 3 is displaced from the dotted line B state to the dotted line A state by an elastic restoring force. For this reason, the volume of the pump chamber 25 increases. Therefore, the fluid flows into the inflow port 211a from the outside.

  When switching from the low voltage state to the non-use state, the internal pressure of the sealing case 60 is decreased. That is, the air inside the sealing case 60 is sucked by the gas suction device 64. When the internal pressure of the sealing case 60 decreases, the membrane member 3 moves back to a substantially flat state, that is, a state where it is not elastically deformed in the vertical direction.

  The diaphragm actuator 1 according to the present embodiment and the diaphragm actuator according to the second embodiment have the same functions and effects with respect to parts having the same configuration. Moreover, according to the diaphragm type actuator 1 of this embodiment, a fluid can be pumped by switching a low voltage state and a high voltage state.

<Others>
The embodiment of the diaphragm actuator of the present invention has been described above. However, the embodiment is not particularly limited to the above embodiment. Various modifications and improvements that can be made by those skilled in the art are also possible.

  For example, in the first embodiment, air is used for regulating the pressure inside the sealing case 60, but other gases such as nitrogen and rare gases may be used. A compressor may be used as the gas supply device 61. Further, as the gas supply device 61, an existing gas transportation pipe may be used in a factory or the like. Further, a liquid such as water or oil may be used for adjusting the pressure inside the sealing case 60. In this case, instead of the gas supply device 61, a liquid supply device such as a pump may be arranged as a pressure adjusting unit. Note that the pressure adjusting fluid (gas or liquid) preferably has an insulating property in order to suppress leakage from the electrode film 300.

  In the second embodiment, the solenoid 80 is used as the counter member of the present invention, but a hydraulic cylinder, an air cylinder, a ball screw, or the like may be used. Further, the shaft 801 may be driven by converting the rotational force of the motor into a linear force by a rack and pinion mechanism or the like.

  Moreover, in 3rd embodiment, the to-be-engaged hole 510 which penetrates the rod part 51 as a to-be-engaged part was arrange | positioned. However, the engaged portion does not have to penetrate the rod portion 51. That is, the engaged recess may be formed on the outer peripheral surface of the rod portion 51 as the engaged portion.

  A vacuum pump may be used as the gas suction device 64 in the diaphragm type actuator 1 of the fourth embodiment. In the fourth embodiment, the diaphragm type actuator 1 is provided with one inlet 211a and one outlet 211b. However, a plurality of inflow ports 211a and a plurality of outflow ports 211b may be arranged in the diaphragm actuator 1. Moreover, the arrangement number of the inflow port 211a and the arrangement number of the outflow port 211b do not need to correspond.

  Moreover, in the said embodiment, although the insulating film 31 was made from nitrile rubber, the material of the insulating film 31 is not specifically limited. It is preferable that the dielectric film 301 can be expanded and contracted according to the expansion and contraction of the dielectric film 301. For example, silicone rubber, acrylic rubber, ethylene-propylene-diene terpolymer (EPDM), natural rubber (NR), butyl rubber (IIR), isoprene rubber (IR), acrylonitrile-butadiene copolymer rubber (NBR), hydrogen Flexible materials such as nitrile rubber (H-NBR), hydrin rubber, chloroprene rubber (CR), and urethane rubber are suitable. In addition, when the material of the insulating film 31 and the material of the dielectric film 301 are matched (including the case where only the base material is matched), the deformation of the insulating film 31 can more easily follow the deformation of the dielectric film 301.

  Moreover, the material of case 2 is not specifically limited. Various resins and various metals may be used. Moreover, in the said embodiment, although the coil spring 4 was arrange | positioned as a biasing member, you may arrange | position other types of springs, such as a leaf | plate spring and a disc spring. An elastomer may be used as the biasing member. Moreover, in the said embodiment, although the film | membrane member 3 was fixed with the clamp ring 32, you may fix by other methods, such as adhesion | attachment.

  Also, the type of dielectric elastomer that forms the dielectric film 301 is not particularly limited. The dielectric film 301 only needs to be deformed according to the electrostatic attractive force between the electrode films 300 adjacent in the vertical direction via the dielectric film 301. In addition to nitrile rubber, for example, one or more kinds selected from silicone rubber, fluorine rubber, urethane rubber, acrylic rubber, ethylene propylene rubber, styrene butadiene rubber, and natural rubber may be used. These dielectric elastomers are suitable for forming the dielectric film 301 because they have high dielectric properties and high dielectric breakdown properties. Further, the number of stacked electrode films 300 and dielectric films 301 in the film member 3 is not particularly limited.

  In the above embodiment, the urging force of the coil spring 4 is applied in the direction in which the membrane member 3 is pressed. However, the urging force of the coil spring 4 may be applied in the direction in which the membrane member 3 is pulled.

1: Diaphragm actuator, 2: Case, 3: Membrane member, 4: Coil spring, 5: Output member, 6: Pressure adjusting member, 7: Spacer.
20: Membrane port, 21: Bottom wall portion, 22: Flange portion, 23: Membrane fixing groove, 25: Pump chamber, 30: Stretchable membrane, 31: Insulating membrane, 32: Clamp ring, 50: Flange portion, 51 : Rod portion, 60: Sealing case, 61: Gas supply device (pressure adjusting portion), 62: Bolt, 64: Gas suction device (pressure adjusting portion), 80: Solenoid (counter member), 81: Lock member, 82 : Spring seat member, 90: driven member.
210: output hole, 211a: inflow port, 211b: outflow port, 220: bolt fixing hole, 300: electrode film, 301: dielectric film, 510: engaged hole, 600: sealing port, 601: upper bottom wall 601a: gas supply hole, 601b: spring seat, 601c: gas suction hole, 602: flange portion, 602a: bolt insertion hole, 800: case, 801: shaft, 801a: flange portion, 801b: rod portion, 820: bottom Wall part, 821: convex part.
S: Switch.

Claims (7)

A case where a membrane opening was opened,
A dielectric film made of a dielectric elastomer that is interposed between at least a pair of the electrode films among the plurality of electrode films and expands and contracts in a plane direction by a change in applied voltage between the pair of electrode films. And a membrane member that seals the membrane tensioning port in a state where the peripheral edge portion is fixed to the rim of the membrane tensioning port,
A biasing member capable of applying a biasing force to the membrane member in a driving direction intersecting the surface direction of the membrane member;
A suppressing member capable of suppressing at least a part of the biasing force applied to the membrane member;
With
It is possible to switch between a non-use state, a low voltage state and a use state where the applied voltage can be switched to a higher voltage state than the low voltage state,
In the non-use state, the suppressing member suppresses at least a part of the urging force applied to the membrane member,
In the use state, the restraining member releases the biasing force applied to the membrane member,
In the low voltage state, the biasing force is applied to the membrane member,
In the high voltage state, with the peripheral edge portion fixed to the mouth edge portion, the membrane member relaxes in an attempt to extend in the surface direction, and depending on the amount of relaxation of the membrane member, A diaphragm actuator that deforms the membrane member in the driving direction. The restraining member includes a sealing case in which a sealing port that is installed under the membrane extending port is opened via the membrane member, and a pressure adjusting unit that can adjust the internal pressure of the sealing case. A pressure regulating member,
2. The diaphragm actuator according to claim 1, wherein in the non-use state, at least a part of the urging force applied to the membrane member is canceled by adjusting the internal pressure. The biasing member applies the biasing force to one surface of the membrane member,
The restraining member is a counter member capable of applying a counter biasing force in a direction opposite to the biasing force to the other surface facing the one surface of the membrane member,
The diaphragm actuator according to claim 1, wherein in the non-use state, at least a part of the biasing force is canceled by the counter biasing force.   The diaphragm actuator according to any one of claims 1 to 3, wherein the urging member is a coil spring.   The diaphragm actuator according to any one of claims 1 to 4, further comprising an output member connected to the membrane member so as to be capable of transmitting power and capable of reciprocating in the driving direction in accordance with deformation of the membrane member. . The case further includes a bottom wall portion facing the extension opening and having an output hole formed therein,
The output member includes a flange portion that contacts the membrane member, and a rod portion that protrudes from the flange portion and is inserted into the output hole so as to be reciprocally movable and has an engaged portion on the outer peripheral surface. ,
The biasing member is interposed between the flange portion and the bottom wall portion in an elastically compressed state.
The suppression member is a lock member that can be engaged with and disengaged from the engaged portion,
In the non-use state, the lock member is engaged with the engaged portion to restrict the movement of the rod portion, and at least a part of the urging force applied to the membrane member via the flange portion is reduced. The diaphragm actuator according to claim 5, wherein the diaphragm actuator is shut off.   The case further includes a pump chamber whose volume changes according to deformation of the membrane member, an inflow port through which fluid flows into the pump chamber from the outside according to volume change of the pump chamber, and a volume of the pump chamber The diaphragm actuator according to any one of claims 1 to 4, further comprising an outflow port through which fluid flows out from the pump chamber in response to a change.

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