JP6643866B2 - Micro displacement output device - Google Patents

Description

  The present invention relates to a small displacement output device, and more particularly to a small displacement output device having a membrane portion that is elastically deformed in a planar shape by gas pressure.

  Moving mechanisms using gas actuators generate less contamination, generate no electromagnetic noise, and are less affected by temperature changes, vibration, and noise than other mechanisms such as piston / cylinder mechanisms and small stepping motors. . Therefore, it is expected to be used not only for positioning actuators such as semiconductor devices, but also for actuators for canceling vibrations in vibration isolators. Therefore, it has been proposed to use a gas actuator to configure a responsive minute movement mechanism.

  For example, Patent Literature 1 includes a housing portion and a lid portion as a micro-displacement output device, and its internal space includes a plurality of plate-shaped movers aligned with a support shaft and an output mover. Configurations are disclosed. Here, when a gas having a control gas pressure is supplied from the gas supply port of the housing toward the plurality of plate-like movers, the gas passes through each gap between adjacent plate-like movers and the like. The gas flows from the inner diameter side to the outer diameter side and is exhausted. At this time, due to the action of the gas bearing mechanism, the gap between the respective gaps changes according to the control gas pressure against the pressing force of the membrane-shaped thin plate serving as the lid, and the gap is minutely displaced. The displacement or the force corresponding to the displacement can be taken out.

  According to the technique of Patent Document 1, since the displacement or force is output by the control gas pressure using the action of the gas bearing mechanism, the displacement can be performed with an accuracy of 1 μm or less without performing the feedback control by detecting the displacement or speed. It is possible to do.

  Patent Literature 2 discloses an appropriate minute displacement output device that does not require the accuracy of the technology of Patent Literature 1, omits a plurality of plate-like movers, and detects displacement of a membrane portion that is elastically deformed in a plane instead. A configuration that includes a displacement detection unit that performs the operation is described.

Japanese Patent No. 4106392 JP 2010-196844 A

  A displacement or a force corresponding to the displacement can be applied to an external load by using a membrane portion that is elastically deformed by the control gas pressure. Here, it is convenient if a wide range from the pressing force to the retraction force can be obtained as the force applied to the load. It is desired that permanent deformation of the membrane does not occur even if the force applied to the load is increased.

  An object of the present invention is to provide a small displacement output device capable of outputting a wide range of force from a pressing force to a retraction force as a force applied to a load. Another object is to provide a small displacement output device that can suppress permanent deformation of the membrane even when the force applied to the load is increased. The following measures contribute to at least one of the above objects.

A minute displacement output device according to the present invention forms a housing having a gas chamber recess surrounded by a cylindrical outer peripheral portion, and forms a gas chamber covering the gas chamber recess of the housing, and supplies the gas to the gas chamber. A disk-shaped membrane portion that is elastically deformed in a planar shape in accordance with the control gas pressure to be applied, is made of a thin metal plate, and is hermetically attached to the cylindrical outer peripheral portion of the housing portion at the outer peripheral mounting portion. and the membrane unit, and an output shaft unit that outputs a displacement caused by elastic deformation of the membrane portion to the outside, is disposed in intimate wear on the upper surface of the membrane portion, and the elastic members for suppressing deformation suppressing excessive deformation of the membrane portion, the provided elastic members for suppressing deformation may have a periphery attachment portion attached to the cylindrical outer periphery of the casing with the outer peripheral attaching portion of the membrane portion, thin metal plate which have the same outer diameter as the membrane portion The spring portion, the displacement rigidity in the axial direction along the output shaft portion is Characterized in that less than vertical displacement stiffness.

In the micro displacement output device according to the present invention, an elastic member for initial pressing that applies a predetermined initial pressing force to the membrane portion along the axial direction of the output shaft portion, and the elastic member for initial pressing is a housing. A metal thin plate spring portion having an outer peripheral mounting portion mounted on the cylindrical outer peripheral portion of the portion, and an inner peripheral mounting portion mounted on the output shaft, wherein the axial displacement rigidity along the output shaft portion is Smaller than the displacement rigidity in the direction perpendicular to the direction, the inner peripheral mounting portion is arranged at a predetermined interval along the axial direction of the output shaft portion from the inner peripheral portion of the membrane portion corresponding to the initial pressing force. Is preferred .

  In the minute displacement output device according to the present invention, the elastic member for initial pressing includes a first elastic member and a second elastic member which are arranged in parallel at a predetermined interval in the axial direction. Is preferred.

  In the minute displacement output device according to the present invention, the thin plate spring portion has a predetermined plate thickness, and the displacement rigidity in the axial direction along the output shaft portion is smaller than the displacement rigidity in the direction perpendicular to the axial direction. Preferably, a spring plate is used, the first elastic member is formed of a first predetermined number of predetermined spring plates, and the second elastic member is formed of a second predetermined number of predetermined spring plates.

  In the minute displacement output device according to the present invention, it is preferable that the elastic member for suppressing deformation is constituted by a third predetermined number of predetermined spring plates.

  It is preferable that the minute displacement output device according to the present invention further includes a displacement detection unit that detects displacement due to elastic deformation of the membrane unit.

  ADVANTAGE OF THE INVENTION According to the micro displacement output apparatus which concerns on this invention, it is provided with the disk-shaped membrane part elastically deformed planarly according to control gas pressure, and the elastic member for deformation suppression which suppresses the excessive deformation of a membrane part. Therefore, excessive deformation of the membrane part can be suppressed.

  According to the minute displacement output device according to the present invention, a disk-shaped membrane portion elastically deformed in a planar shape according to the control gas pressure, and a predetermined initial pressing force on the membrane portion along the axial direction of the output shaft portion. And an elastic member for initial pressing. The membrane is configured to apply a pressing force to the load as elastic deformation according to the control gas pressure, and to set the initial drawing force when the control gas pressure is zero to a force that pulls in the load, thereby providing a force to the load. It can output in a wide range from the pressing force to the retraction force.

  In the minute displacement output device according to the present invention, since the elastic members for initial pressing include the first elastic member and the second elastic member which are arranged in parallel at a predetermined interval in the axial direction with respect to each other, these elastic members are provided. The output shaft section that outputs the deformation moves along the axial direction. Thus, the displacement applied to the load or a force corresponding to the displacement is always applied to the load in a fixed direction.

  In the minute displacement output device according to the present invention, the first elastic member is constituted by a first predetermined number of predetermined spring plates, and the second elastic member is constituted by a second predetermined number of predetermined spring plates. By setting the predetermined number of sheets according to the specification of the force applied to the load by the minute displacement output device, permanent deformation of the predetermined spring plate can be suppressed.

Minute displacement output apparatus according to the present invention, together with the elastic member for the initial pressing, are disposed closely to the membrane portion comprises an elastic member for suppressing deformation suppressing excessive deformation of the membrane portion. As a result, the force applied to the load can be output in a wide range from the pressing force to the retraction force, and in that case, excessive deformation of the membrane portion can be suppressed.

  In the minute displacement output device according to the present invention, it is preferable that the elastic member for suppressing deformation of the membrane portion is configured by a third predetermined number of predetermined spring plates. By setting a predetermined number of elastic members for deformation suppression according to the specification of the force applied to the load by the minute displacement output device, permanent deformation of the membrane portion can be suppressed.

  In the minute displacement output device according to the present invention, since the displacement detection unit that detects the displacement due to the elastic deformation of the membrane unit is provided, by reflecting the detected value to the control gas pressure, the displacement applied to the load or the force corresponding to the displacement is obtained. The accuracy is improved.

It is a figure showing appearance of a minute displacement output device concerning the present invention. FIG. 1A is a top view, and FIG. 1B is a front view. FIG. 2 is a sectional view taken along the line CC of FIG. 1. It is the elements on larger scale of FIG. 3A is an enlarged view of a portion A in FIG. 2, and FIG. 3B is an enlarged view of a portion B in FIG. It is a figure showing a predetermined spring board in a minute displacement output device concerning the present invention. It is a lineblock diagram of a displacement detector in a minute displacement output device concerning the present invention. It is an exploded view of the minute displacement output device concerning the present invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The dimensions, materials, numbers, numerical values, and the like described below are examples for explanation, and other conditions can be used according to the purpose of use. In the following, the same reference numerals are given to the same elements in all the drawings, and redundant description will be omitted.

  FIG. 1 is a diagram showing a configuration of the small displacement output device 10. FIG. 1A is a top view, and FIG. 1B is a front view.

The micro-displacement output device 10 has an outer shape composed of a housing portion 12 and a cover 14, and a membrane portion 16 is arranged in an internal space of the cover 14. The membrane portion 16 is elastically deformed in a planar shape in response to an external control gas pressure (−P _A1 to + P _A2 ), and outputs a force (−F _O1 to + F _O2 ) corresponding to the displacement of the elastic deformation. 20, and the magnitude of the displacement of the membrane section 16 is detected by the displacement detecting section 30. The detection value of the displacement detection unit 30 is fed back to the control gas pressure by a control device (not shown). As a result, a highly accurate displacement or a force corresponding to the displacement is output to the output shaft section 20.

Since a load (not shown) is connected to the output shaft section 20, the load can be applied with a wide range of force from a pulling force ( _-FO1 ) to a pressing force (+ _FA2 ). Since the membrane portion 16 is displaced by planar elastic deformation, the displacement or a force corresponding to the displacement is output to the output shaft portion 20. For example, when the load is a positioning unit or the like, the output of the output shaft unit 20 can be used as “displacement”. As another example, when the load is a vibration isolation unit or the like, the output of the output shaft unit 20 is used. Can be used as "force". Hereinafter, the output of the output shaft unit 20 is referred to as “force”.

  FIG. 1 shows an X direction, a Y direction, and a Z direction as three orthogonal directions. The Z direction is the axial direction of the output shaft unit 20, the direction of the "force" that is the output of the output shaft unit 20, the "+" side is the direction of the pressing force against the load, and the "-" is the retraction force against the load. Direction. The X direction and the Y direction are directions perpendicular to the direction of the “force” of the output shaft section 20. Here, the housing section 12 and the cover 14 have a substantially square outline in a top view, and one side of the substantially square side. Is defined as an X direction, and a direction perpendicular to the X direction is defined as a Y direction. In the example of FIG. 1, since the upper surface of the output shaft section 20 is substantially rectangular, the direction parallel to the long side is defined as the X direction.

  FIG. 2 is a sectional view taken along the line CC of FIG. The CC line is a line that passes through the center position of the output shaft section 20 on the XY plane and is parallel to the X direction.

  The housing 12 is a member having substantially square flanges at both ends in the Z direction of the cylindrical portion. A control gas supply port 70 to which a gas having a control gas pressure from a gas supply source (not shown) is supplied is provided on the flange portion on the end side in the −Z direction. An annular cylindrical outer peripheral portion 74 is provided so as to protrude from the upper surface of the flange portion on the + Z direction end side. A gas flow path 72 extending in the Z direction is provided inside the housing 12. One end of the gas flow path 72 is connected to the control gas supply port 70, and the other end is opened to a gas chamber recess 75 which is a space surrounded by a cylindrical outer peripheral portion 74. The gas chamber dent 75 becomes the gas chamber 76 by arranging and covering the upper surface of the cylindrical outer peripheral portion 74 with the membrane portion 16.

  A displacement detection unit 30 is arranged at the center of the housing 12. The displacement detection unit 30 includes a probe unit 31 that displaces integrally with the displacement of the output shaft unit 20 along the Z direction, and a differential coil unit 34 that detects the displacement of the probe unit 31 along the Z direction. Details of the displacement detection unit 30 will be described later.

  The casing 12 may be formed by processing an appropriate metal material into a predetermined shape. To describe the dimensions of the housing 12 as an example, the outer diameter of the cylindrical portion is about 30 to 50 mm, the side of the substantially square flange is about 40 to 60 mm, and the outer diameter of the cylindrical outer peripheral section 74 is about 40 mm. The width of the cylindrical outer peripheral portion 74, which is the difference between the outer shape and the inner diameter, is about 1 mm to 3 mm. This is an example for explanation, and can be appropriately changed according to the specifications of the minute displacement output device 10.

  The cover 14 is a substantially square cup-shaped member having a circular opening 15 (see FIG. 6) on the −Z direction side. The cover 14 has a central opening through which the output shaft 20 passes. The outer shape of the cover 14 in the plan view is substantially the same as the substantially square outer shape of the flange portion of the housing 12, and the circular opening 15 is slightly larger than the outer diameter of the annular cylindrical outer peripheral portion 74 of the housing 12. It has a large inner diameter. Holes for passing a plurality of bolts 40 and 42 are provided at four corners outside the circular opening 15 on the outer periphery of the substantially square outer shape of the cover 14 (see FIG. 1A). The cover 14 and the housing 12 are integrally fixed by the plurality of bolts 40 and 42.

  As the cover 14, similarly to the case 12, a cover formed by processing an appropriate metal material into a predetermined shape can be used. Taking the dimensions of the cover 14 as an example, the height dimension along the Z direction is about 10 to 20 mm, and one side of the substantially square is about 40 to 60 mm. This is an example for explanation, and can be appropriately changed according to the specifications of the minute displacement output device 10.

  The membrane part 16 is a thin disk having a center hole. The outer diameter of the thin disk is set to be the same as the outer diameter of the cylindrical outer peripheral portion 74 of the housing portion 12, and the inner diameter of the center hole is set to a size through which the output shaft portion 20 passes. The membrane portion 16 hermetically covers the gas chamber recess 75 surrounded by the cylindrical outer peripheral portion 74, whereby the gas chamber recess 75 becomes a gas chamber 76. A gas having a control gas pressure is supplied to the gas chamber 76 from a control gas supply port 70 via a gas flow path 72. The membrane portion 16 is elastically deformed in a planar shape according to the magnitude of the control gas pressure.

As the membrane section 16, a thin metal disk is used. To give an example of the dimensions of the membrane part 16, the outer diameter is the same as the outer diameter of the cylindrical outer peripheral part 74 of the housing part 12, and is about 40 to 50 mm. The thickness of the membrane 16, the strength is insufficient with respect to the maximum value of the too thin and the control gas pressure (-P _A1 ~ + P _A2), it is too thick, a wide range of control gas pressure (-P _A1 ~ + P _A2) The elastic deformation in the form of a plane does not become linear. Therefore, the thickness of the membrane section 16 is set to an appropriate value in consideration of the specifications of the small displacement output device 10.

  The output shaft portion 20 is formed by integrally assembling the first shaft member 22, the second shaft member 24, and the connection shaft 26. The first shaft member 22 is a shaft member having a flange portion 80 that comes into contact with the membrane portion 16. The second shaft member 24 is a shaft member having a flange portion 82 having a screw hole 28 for mounting a load (not shown) at one end and a flange portion 84 at the other end facing the flange portion 80 of the first shaft member 22. . The connection shaft 26 is a shaft member that integrally connects the first shaft member 22 and the second shaft member 24 to each other by using screw means. At the tip of the connection shaft 26, a probe unit 31 constituting a part of the displacement detection unit 30 is arranged. The connection of each member constituting the output shaft section 20 will be described later with reference to an exploded view of FIG.

  The first shaft member 22, the second shaft member 24, and the connection shaft 26, except for the probe portion 31, may be formed by processing an appropriate metal material to have a predetermined shape.

  In the internal space of the circular opening 15 of the cover 14, the membrane 16 and the output shaft 20 are arranged, and further, a plurality of spacers and a plurality of thin plate springs are arranged. These arrangement relationships will be described with reference to FIG. 3, which is a partially enlarged view of FIG. 3A is an enlarged view of a portion A in FIG. 2, and FIG. 3B is an enlarged view of a portion B in FIG.

  In the portion A, between the cylindrical outer peripheral portion 74 of the housing portion 12 and the bottom portion 17 of the circular opening 15 of the cover 14, the membrane portion 16, the elastic member 50 for suppressing deformation, the first elastic member 54, The spacer 58, the second elastic member 60, and the spacer 64 are arranged in this order.

  In the portion B, between the flange portion 80 of the first shaft member 22 and the flange portion 84 of the second shaft member 24 in the output shaft portion 20, the membrane portion 16, the elastic member 50 for suppressing deformation, the spacer 52, The first elastic member 54, the spacer 56, the second elastic member 60, and the spacer 62 for height adjustment are arranged in this order.

The outer diameter of the spacers 58 and 64 in the portion A is the same as the outer diameter of the cylindrical outer peripheral portion 74 of the housing portion 12, and the inner diameter is the same as the inner diameter of the cylindrical outer peripheral portion 74 of the housing portion 12. The spacers 52, 56, and 62 in the portion B have the same inner diameter as the outer diameter of the shaft portion of the first shaft member 22, and the same outer diameter as the outer diameter of the flange portion 80 of the first shaft member 22. The spacer 56 and the spacer 58 have the same thickness t ₀ . The thickness t ₁ of the spacer 52 and the thickness t ₂ of the spacer 64 have a relationship of t ₂ > t ₁ .

As the elastic members 50, the first elastic members 54, and the second elastic members 60 for suppressing deformation, a predetermined number of predetermined spring plates 100 are used. In the example of FIG. 3, an N ₁ = 4 a predetermined number of the first elastic member 54 as a first predetermined number N _1, N ₂ a predetermined number of the second elastic member 60 as a second predetermined number N ₂ = 3 , and N ₃ = 1, where the predetermined number of elastic members 50 for suppressing deformation is the third predetermined number N ₃ . This is merely an example, and N ₁ , N ₂ , and N ₃ may be one or more, and the specific predetermined value is the control gas pressure (−) that is the operation specification of the small displacement output device 10. P _A1 to + P _A2 ) and the output force (−F _O1 to + F _O2 ).

  FIG. 4 shows a plan view of the predetermined spring plate 100. The predetermined spring plate 100 includes an inner peripheral support portion 104 of an annular portion outside the center hole 102, an outer peripheral support portion 106 of an outer annular portion, and a plurality of openings between the inner peripheral support portion 104 and the outer peripheral support portion 106. This is a leaf spring having a predetermined shape provided with the portion 108. By the plurality of arms 110 having a narrow width and a curved shape formed between the plurality of openings 108, the predetermined spring plate 100 is configured such that the corrugated arm or the cloud-shaped arm as a whole is It has a form arranged between the support portion 104 and the support portion 104. The predetermined spring plate 100 is easily displaced in the axial direction and hardly displaced in the radial direction perpendicular to the axial direction by the arm portion 110 having the thin bent shape. That is, in the predetermined spring plate 100, the displacement rigidity in the axial direction along the output shaft portion 20 is smaller than the displacement rigidity in the direction perpendicular to the axial direction.

  As the predetermined spring plate 100, a thin metal plate punched into a predetermined shape or formed into a predetermined shape by etching can be used. As the metal material, a stainless steel material or the like can be used. The thickness of the predetermined spring plate 100 is larger than the thickness of the membrane part 16. To give an example, the thickness of the predetermined spring plate 100 is about 0.15 mm to 0.3 mm, with the thickness of the membrane part 16 being about 0.1 mm.

  The outer diameter of the predetermined spring plate 100 is set to be the same as the outer diameter of the cylindrical outer peripheral portion 74 of the housing 12, and the diameter of the center hole 102 is slightly larger than the outer diameter of the shaft of the first shaft member 22. Is set. Further, the width of the inner peripheral supporting portion 104 is set to be the same as the width of the spacers 52, 56, and 62 in the B portion, and the width of the outer peripheral supporting portion 106 is set to be the same as the width of the spacers 58 and 64 in the A portion. You.

  As a result, the outer peripheral support portion 106 of each predetermined spring plate 100 is sandwiched between the cylindrical outer peripheral portion 74 of the housing portion 12, the spacers 58 and 64, and the bottom portion 17 of the circular opening 15 of the cover 14 at the portion A. Acts as a peripheral mounting part that can be mounted. The inner peripheral support portion 104 is provided between the flange portion 80 of the first shaft member 22, the spacers 52 and 56, the height adjusting spacer 62, and the flange portion 84 of the second shaft member 24 in the output shaft portion 20 at the portion B. It works as an inner peripheral mounting part which is sandwiched and mounted on each.

  The predetermined spring plate 100 that constitutes the elastic member 50 for suppressing deformation is arranged in close contact with the membrane portion 16 and suppresses excessive deformation of the membrane portion 16.

The first elastic member 54 and the second elastic member 60 are elastic members for initial pressing for applying a predetermined initial pressing force to the membrane 16 along the axial direction of the output shaft 20. The first elastic member 54 and the second elastic member 60 are each composed of a predetermined number of predetermined spring plates 100. As shown in FIGS. 3A and 3B, the axial interval between the membrane portion 16, the elastic member 50 for suppressing deformation, and the first elastic member 54 is set at the outer peripheral support portion, which is the portion A. Although the distance is zero, the interval corresponding to the thickness t ₁ of the spacer 52 in the inner peripheral support portion which is the portion B. That is, the inner peripheral mounting portion of the first elastic member 54 is offset from the inner peripheral portion of the membrane 16 by a predetermined distance in the + Z direction along the axial direction of the output shaft portion 20 by the thickness t ₁ of the spacer 52. Be placed.

Due to this offset, the first elastic member 54 gives an initial pressing force in the “−Z” direction to the membrane part 16. The first elastic member 54 is an elastic member for initial pressing. The initial pressing force is a “force in the −Z direction” output to the output shaft portion 20 when the control gas pressure is zero, and serves as a pulling force against the load. When the control gas pressure becomes a positive value, the membrane unit 16 generates a “+ Z direction force” according to the control gas pressure, and subtracts “the force in the −Z direction” corresponding to the initial pressing force. "Force" to the output shaft section 20. By applying the initial pressing force to the membrane section 16 in this manner, when the control gas pressure changes from the negative pressure “−P _A1 ” to the positive pressure “+ P _A2 ”, the output shaft section 20 is pressed. Applies ( _-FO1 to + _FO2 ) to the load as "force" in a wide range from "pulling force" to "pressing force".

As shown in FIG. 3A, the second elastic member 60 is disposed at a distance corresponding to the thickness t ₀ of the spacer 58 with respect to the first elastic member 54 in the outer peripheral support portion, which is the portion A. . As shown in FIG. 3B, in the inner peripheral supporting portion, which is a portion B, the first elastic member 54 is disposed at a distance corresponding to the thickness t ₀ of the spacer 56. That is, the second elastic member 60 and the first elastic member 54 have a parallel relationship with each other in the Z direction. That is, the first elastic member 54 and the second elastic member 60 move along the Z axis integrally as a whole while maintaining a parallel state. As a result, the output shaft portion 20 that outputs the displacement of the planar elastic deformation of the membrane portion 16 or a force corresponding to the displacement moves along the Z-axis direction. As a result, the displacement applied to the load by the output shaft section 20 or a force corresponding to the displacement is always applied to the load in a fixed direction.

  Returning to FIG. 2 again, the displacement detection section 30 provided in the housing section 12 is a displacement sensor of a linear variable differential transformer (LVDT) type.

  FIG. 5 is a detailed configuration diagram of a portion related to the displacement detection unit 30. The displacement detection unit 30 includes a probe unit 31 attached to a tip of the connection shaft 26 of the output shaft unit 20, and a differential coil unit 34. The probe section 31 includes a magnetic body shaft 32 on the distal end side and a non-magnetic body shaft 33 on the connection shaft 26 side. The non-magnetic shaft 33 is provided for magnetically separating the magnetic shaft 32 and the connection shaft 26 from each other. The differential coil unit 34 detects a displacement of the magnetic body shaft 32 along the Z direction. The housing 12 has a bottomed hole 13 for passing the probe 31 along the Z direction. The dry tube 112 and the shield part 114 are arranged in the bottomed hole 13. The dry tube 112 is a waterproof tube that does not allow moisture to pass through. The shield part 114 air-tightly separates the probe part 31 moving in the atmosphere of the same gas pressure as the gas chamber 76 from the differential coil part 34, and the gas in the gas chamber 76 It is a shield sheath having a function of preventing leakage through a hole through which a wire passes. The probe section 31 moves in a sheath of the shield section 114 extending in the Z direction.

  The differential coil unit 34 includes a primary-side excitation coil 116 and a secondary-side detection coil 118. The detection coil 118 on the secondary side is composed of two coils connected with opposite polarities. Leader wires are respectively connected to both ends of the primary excitation coil 116, and both terminals of the two connected coils and a connection point to which the two coils are connected are connected to the secondary detection coil 118. Are connected to the respective lead wires. A total of five outgoing lines are drawn out from the input / output port 120 to the outside.

  FIG. 5 shows the detection control unit 130, which is not a component of the small displacement output device 10. The detection control unit 130 includes an excitation circuit 132 connected to the excitation coil 116, a detection circuit 134 connected to the detection coil 118, and a displacement output circuit 136 that converts an output value of the detection circuit 134 into a displacement of the membrane unit 16 and outputs the displacement. including. The displacement data output from the displacement output circuit 136 is transmitted to a control device (not shown) and fed back to the setting of the control gas pressure. This feedback improves the accuracy of the value of the “force” output by the output shaft unit 20.

  The procedure for assembling the small displacement output device 10 having such a configuration will be described with reference to the exploded view of FIG. FIG. 6 is an exploded view of the sectional view of FIG. In the housing 12, a cylindrical outer peripheral portion 74 protrudes in an annular shape on the upper surface which is the end surface in the + Z direction. The region surrounded by the cylindrical outer peripheral portion 74 is a gas chamber depression 75 that becomes the gas chamber 76. The first shaft member 22 of the output shaft portion 20 is arranged at the center of the gas chamber recess 75.

  The first shaft member 22 is a shaft member having a flange portion 80 at an end in the -Z direction. The first shaft member 22 is provided with a through hole 87 through which the probe unit 31 passes, and a part of the through hole 87 is a screw hole 88. The screw hole 88 meshes with the external thread 86 of the connection shaft 26 of the output shaft 20. The probe portion 31 is press-fitted into a portion of the through hole 87 where the screw hole 88 is not provided, as described later.

  The membrane portion 16 is a thin metal disk having the same outer diameter as the outer diameter of the cylindrical outer peripheral portion 74 and an inner diameter slightly larger than the outer diameter of the shaft portion of the first shaft member 22. By passing the shaft portion of the first shaft member 22 through the inner diameter hole of the membrane portion 16, the inner peripheral mounting portion on the inner peripheral side of the membrane portion 16 is arranged on the upper surface of the flange portion 80 of the first shaft member 22, and the outer peripheral mounting portion on the outer peripheral side is arranged. The part is arranged on the upper surface of the cylindrical outer peripheral part 74 of the housing part 12. Thereby, the membrane portion 16 covers the gas chamber recess 75, the inner peripheral wall of the cylindrical outer peripheral portion 74 of the housing portion 12, the bottom surface of the gas chamber recess 75, the inner peripheral wall of the flange portion 80 of the first shaft member 22, The space surrounded by the lower surface of the membrane part 16 forms the gas chamber 76. A gas having a control gas pressure is supplied to the gas chamber 76 from a control gas supply port 70 of the housing 12 via a gas flow path 72.

  The elastic member 50 for suppressing deformation is constituted by one predetermined spring plate 100 described with reference to FIG. The predetermined spring plate 100 has the same outer diameter as the outer diameter of the cylindrical outer peripheral portion 74 and has an inner diameter slightly larger than the outer diameter of the shaft portion of the first shaft member 22. That is, the inner diameter and the outer diameter of the predetermined spring plate 100 are the same as the inner diameter and the outer diameter of the membrane portion 16. The shaft member of the first shaft member 22 is passed through the inner diameter hole of the deformation suppressing elastic member 50, and the deformation suppressing elastic member 50 is disposed in close contact with the upper surface of the membrane portion 16.

The spacer 52 is a metal ring whose outer diameter is the same as the outer diameter of the flange portion 80 of the first shaft member 22, whose inner diameter is slightly larger than the outer diameter of the shaft portion of the first shaft member 22, and whose thickness is t _1. is there. The ring-shaped width of the spacer 52 is the same as the width of the inner peripheral support 104 of the predetermined spring plate 100. By passing the inner diameter hole of the spacer 52 through the shaft of the first shaft member 22, the ring-shaped portion of the spacer 52 is disposed on the upper surface of the inner peripheral support 104 of the predetermined spring plate 100.

  Next, four predetermined spring plates 100 constituting the first elastic member 54 are arranged. By passing the shaft portions of the first shaft member 22 through the inner diameter holes of the four predetermined spring plates 100, the inner peripheral support portions 104 of the four predetermined spring plates 100 are arranged on the upper surface of the ring-shaped portion of the spacer 52. You.

Subsequently, the spacer 56 and the spacer 58 are arranged on the upper surface of the predetermined spring plate 100 disposed on the top of the four predetermined spring plates 100 constituting the first elastic member 54. Inner and outer diameters of the spacer 56 is the same as the inner diameter and outer diameter of the spacer 52, it is different from a thickness of t _0. The spacer 56 is disposed on the upper surface of the inner peripheral support portion 104 of the predetermined spring plate 100 on the uppermost side of the first elastic member 54 by passing the shaft portion of the first shaft member 22 through the inner diameter hole. The inner and outer diameters of the spacer 58 are the same as the inner and outer diameters of the cylindrical outer peripheral portion 74. The thickness is t _0, which is the same as that of the spacer 56. Since the inner diameter of the spacer 58 is sufficiently larger than the outer diameter of the first shaft member 22, the spacer 58 is arranged as it is on the upper surface of the predetermined spring plate 100 on the uppermost side of the first elastic member 54.

  Next, three predetermined spring plates 100 constituting the second elastic member 60 are arranged. By passing the shaft portions of the first shaft member 22 through the inner diameter holes of the three predetermined spring plates 100, the inner peripheral support portions 104 of the three predetermined spring plates 100 are arranged on the upper surface of the ring-shaped portion of the spacer 56. You. The spacer 58 is disposed between the upper surface of the uppermost predetermined spring plate 100 of the first elastic member 54 and the lower surface of the lowermost predetermined spring plate 100 of the second elastic member 60.

  Subsequently, a spacer 62 for height adjustment is arranged. The height adjusting spacer 62 is for adjusting the height position of the output shaft section 20, and may be omitted in some cases. The inner and outer diameters of the height adjusting spacer 62 are the same as the inner and outer diameters of the spacers 52 and 56. The spacer 62 for height adjustment is disposed on the upper surface of the inner peripheral supporting portion 104 of the predetermined spring plate 100 on the uppermost side of the second elastic member 60 by passing the shaft portion of the first shaft member 22 through the inner diameter hole. Is done.

Next, the spacer 64 is arranged. Inner and outer diameters of the spacer 64 is the same as the inner diameter and outer diameter of the spacer 58, it is different from a thickness of t _2. The thickness t ₂ is greater than the thickness t ₁ of the spacer 52.

  Thus, the arrangement of the membrane portion 16, the eight predetermined spring plates 100, and the five spacers 52, 56, 58, 62, 64 is completed. Next, the second shaft member 24 of the output shaft portion 20 and the cover 14 are arranged.

  The second shaft member 24 of the output shaft portion 20 is a shaft member having a substantially rectangular flange portion 82 having a screw hole 28 for mounting a load at the end in the + Z direction, and having a flange portion 84 also at the end in the -Z direction. . The second shaft member 24 has an opening 90 on the flange portion 84 side into which the shaft portion of the first shaft member 22 is fitted, and has an opening 92 on the flange portion 82 side through which the connection shaft 26 passes. The opening 90 and the opening 92 are connected via a step 94 having a center hole. The step portion 94 is for supporting the bolt head of the connection shaft 26, and the inner diameter of the center hole of the step portion 94 is set to a size through which the shaft portion of the connection shaft 26 passes.

  The flange portion 84 of the second shaft member 24 is addressed to the upper surface of the spacer 62 for height adjustment, and the opening 90 is fitted into the shaft portion of the first shaft member 22 so that the first shaft member 22 and the The biaxial member 24 is arranged side by side along the Z direction.

  The connection shaft 26 is a fastening bolt having a head portion and a shaft portion, and a male screw portion 86 is engraved on the shaft portion. The outer diameter of the head is set to a size that can be inserted into the opening 92 of the second shaft member 24 and rotated for tightening. The external thread portion 86 is provided at an intermediate portion of the shaft portion along the Z axis. This is because, except that the male screw portion 86 meshes with the screw hole 88 of the first shaft member 22, the opening 92 of the second shaft member 24, the inner diameter hole of the step portion 94, the opening 90, and the front end side of the shaft portion are the first. This is for insertion into the bottomed hole 13 of the housing 12 through the through hole 87 of the shaft member 22.

  The probe section 31 constituting the displacement detecting section 30 is composed of a magnetic shaft 32 and a non-magnetic shaft 33 above the magnetic shaft 32. The probe section 31 may be integrated with the connection shaft 26, but is preferably separate from the connection shaft 26 because the connection shaft 26, which is a tightening bolt, is rotated. The probe part 31 is press-fitted into the through hole 87 of the first shaft member 22 and is integrated with the first shaft member 22. The position of the magnetic body shaft 32 on the distal end side of the probe unit 31 along the Z direction is set so as to have a predetermined positional relationship with the position of the differential coil unit 34 of the displacement detection unit 30. This position setting is performed by engaging the external thread portion 86 of the connection shaft 26 with the screw hole 88 of the first shaft member 22, and press-fitting the through-hole 87 of the first shaft member 22 at the end of the connection shaft 26 in the −Z direction. This is performed by pressing the end of the probe unit 31 in the + Z direction.

  As described above, while positioning the probe portion 31 in the Z direction, the external thread portion 86 of the connection shaft 26 is engaged with the screw hole 88 of the first shaft member 22 and tightened, so that the first shaft member 22 and the second The shaft member 24 and the connection shaft 26 are integrated. By this integration, between the flange portion 80 of the first shaft member 22 and the flange portion 84 of the second shaft member 24, the membrane portion 16, the predetermined spring plate 100, the spacers 52 and 56, and the spacer 62 for height adjustment Are sandwiched and fixed. The membrane portion 16 and the inner peripheral support portion of the predetermined spring plate 100 are sandwiched and fixed as an inner peripheral fixing portion, and the inner peripheral side of the membrane portion 16 is airtightly fixed. Thus, the output shaft section 20 can output a displacement corresponding to the planar elastic deformation of the membrane section 16 or a force corresponding to the displacement.

  The cover 14 has a substantially square planar shape as shown in FIG. 1, but has a circular opening 15 on the −Z direction side. The inner diameter of the circular opening 15 is set slightly larger than the outer diameter of the annular cylindrical outer peripheral portion 74 of the housing 12. The outer diameter of the membrane part 16, the predetermined spring plate 100, and the spacers 58, 64 is the same as the outer diameter of the annular cylindrical outer peripheral part 74 of the housing part 12. The outer diameter of the membrane 16, the predetermined spring plate 100, and the spacers 58, 64 is set along the inner peripheral wall of the circular opening 15 of the cover 14, and the bottom 17 of the circular opening 15 of the cover 14 is directed to the upper surface of the spacer 64. U. As a result, the membrane portion 16, the predetermined spring plate 100, and the spacers 58 and 64 can be arranged inside the outer periphery of the circular opening 15 of the cover 14.

  As shown in FIG. 1A, holes for passing a plurality of bolts 40 and 42 are provided at four corners on the outer periphery of the substantially square outer shape of the cover 14. Correspondingly, screw holes that engage with the plurality of bolts 40 and 42 are arranged in the housing 12. By integrally fixing the cover 14 to the housing 12 by using a plurality of bolts 40 and 42, the membrane 16, the predetermined spring plate 100, and the spacers 58 and 64 are connected to the bottom 17 of the circular opening 15 of the cover 14. And the cylindrical outer peripheral portion 74 of the housing portion 12 and are fixed. The outer peripheral supporting portion of the membrane portion 16 and the predetermined spring plate 100 is an outer peripheral fixing portion sandwiched and fixed, and the outer peripheral side of the membrane portion 16 is airtightly fixed.

The plurality of predetermined spring plates 100 forming the first elastic member 54 and the second elastic member 60 have a flat shape before the micro displacement output device 10 is assembled, as shown in FIG. When the micro-displacement output device 10 is assembled, the plurality of predetermined spring plates 100 constituting the first elastic member 54 and the second elastic member 60 are moved in the Z direction of the inner peripheral support portion as shown in FIGS. The position along is offset in the + Z direction from the position along the Z direction of the outer peripheral support. As described in FIG. 3, the offset between the axial direction between the membrane portion 16, the deformation suppressing elastic member 50, and the first elastic member 54 is zero in the outer peripheral support portion which is the portion A. , B, the inner peripheral support portion has an interval corresponding to the thickness t ₁ of the spacer 52. Due to this offset, the first elastic member 54 and the second elastic member 60 apply an initial pressing force in the “−Z” direction to the membrane portion 16.

  The cover 14 has a central opening through which the second shaft member 24 constituting the output shaft portion 20 passes. As shown in FIG. 6, a portion 96 of the central opening of the cover 14 is set so as to overlap the outer diameter of the flange portion 84 of the second shaft member 24. This is a safety stopper that prevents the output shaft section 20 from being excessively displaced in the + Z direction. With this central opening portion 96, the cover 14 and the second shaft member 24 appear to be unassembled. Actually, the central opening of the cover 14 is not a circular hole, but has a different dimension in the X and Y directions. Similarly, the flange portion 84 of the second shaft member 24 is not a circular flange, and has different dimensions in the X and Y directions. Utilizing this dimensional difference, the direction of the large dimension of the central opening of the cover 14 and the direction of the large dimension of the flange portion 84 of the second shaft member 24 are matched, and the cover 14 is attached to the shaft portion of the second shaft member 24. Through. Thereafter, the cover 14 is rotated with respect to the second shaft member 24 so that the portion 96 of the central opening of the cover 14 and the outer diameter of the flange portion 84 of the second shaft member 24 have the relationship shown in FIG. In this way, a safety stopper against excessive displacement of the output shaft portion 20 in the + Z direction is provided.

  As described above, the membrane portion 16 which is elastically deformed by the control gas pressure is used to apply a wide range of force from the pressing force to the retraction force to the load, and the permanent deformation of the membrane portion 16 is prevented even when the force applied to the load is increased. The small displacement output device 10 that can be suppressed can be assembled.

  Reference Signs List 10 micro displacement output device, 12 housing part, 13 bottomed hole, 14 cover, 15 circular opening, 16 membrane part, 17 bottom, 20 output shaft part, 22 first shaft member, 24 second shaft member, 26 connection Shaft, 28,88 screw hole, 30 Displacement detector, 31 Probe, 32 Magnetic shaft, 33 Non-magnetic shaft, 34 Differential coil, 40, 42 Bolt, 50 Elastic member for suppressing deformation, 52, 56 , 58, 62, 64 Spacer, 54 First elastic member (elastic member for initial pressing), 60 Second elastic member (elastic member for initial pressing), 70 Control gas supply port, 72 Gas flow path, 74 Tubular Outer periphery, 75 gas chamber recess, 76 gas chamber, 80, 82, 84 flange, 86 male thread, 87 through hole, 90, 92, 108 opening, 94 step, 96 part, 100 predetermined Plate, 102 center hole, 104 inner peripheral support (corresponding to inner peripheral mounting part), 106 outer peripheral supporting part (corresponding to outer peripheral mounting part), 110 arm part, 112 dry tube, 114 shield part, 116 excitation coil, 118 detection Coil, 120 input / output port, 130 detection control unit, 132 excitation circuit, 134 detection circuit, 136 displacement output circuit.

Claims (6)

A housing portion having a gas chamber recess surrounded by a cylindrical outer peripheral portion,
A gas chamber is formed by covering the gas chamber recess of the housing section, and is a disk-shaped membrane section that is elastically deformed in a plane according to a control gas pressure supplied to the gas chamber, and is a thin metal plate. A membrane portion that is configured and hermetically attached to the cylindrical outer peripheral portion of the housing portion at the outer peripheral mounting portion,
An output shaft for outputting displacement due to elastic deformation of the membrane to the outside,
Disposed closely wear on the upper surface of the membrane portion, and the elastic members for suppressing deformation suppressing excessive deformation of the membrane portion,
With
The elastic member for suppressing deformation is
Have a periphery attachment portion attached to the cylindrical outer periphery of the casing with the outer peripheral attaching portion of the membrane portion, a thin metal plate spring portion which have the same outer diameter as the membrane portion, along the output shaft portion A minute displacement output device wherein the axial displacement rigidity is smaller than the axial displacement rigidity. The minute displacement output device according to claim 1,
An elastic member for initial pressing that applies a predetermined initial pressing force to the membrane along the axial direction of the output shaft,
With
The elastic member for initial pressing is
An outer peripheral mounting portion attached to a cylindrical outer peripheral portion of the housing portion, and a metal thin plate spring portion having an inner peripheral mounting portion attached to the output shaft portion,
The displacement rigidity in the axial direction along the output shaft is smaller than the displacement rigidity in the direction perpendicular to the axial direction.
The minute displacement output device, wherein the inner peripheral mounting portion is arranged at a predetermined interval along the axial direction of the output shaft portion from the inner peripheral portion of the membrane portion in accordance with the initial pressing force. The minute displacement output device according to claim 2,
The elastic member for initial pressing is
A minute displacement output device comprising: a first elastic member and a second elastic member arranged in parallel with each other at a predetermined interval in an axial direction. The minute displacement output device according to claim 3,
The thin leaf spring part
Using a predetermined spring plate having a predetermined plate thickness, the displacement rigidity in the axial direction along the output shaft portion is smaller than the displacement rigidity in the direction perpendicular to the axial direction,
The first elastic member is configured by a first predetermined number of predetermined spring plates,
The minute displacement output device, wherein the second elastic member is constituted by a second predetermined number of predetermined spring plates. The minute displacement output device according to claim 4 ,
The minute displacement output device, wherein the elastic member for suppressing deformation is constituted by a third predetermined number of predetermined spring plates. The minute displacement output device according to any one of claims 1 to 5 ,
A minute displacement output device comprising a displacement detection unit for detecting a displacement due to elastic deformation of a membrane unit.

Images