JP5812826B2 - Fluid pressure actuator - Google Patents

Description

  The present invention relates to a fluid pressure actuator, and more particularly to a fluid pressure actuator in which an output shaft extending from a spool can move straight and rotate.

  The fluid pressure actuator can drive the spool linearly by controlling the fluid pressure. By using the spool as the output shaft, linear output positioning control, load control, and the like can be performed on the output shaft. For example, in a chip bonding apparatus, a positioning control in a height direction in which an output shaft that holds a chip moves straight toward a bonding target to a predetermined height position, and a predetermined load at a predetermined predetermined height position. The pressing load control is performed.

  Here, if the output shaft can be rotated around the shaft, the degree of freedom in positioning control is increased. In the chip bonding apparatus, the rotation of the output shaft is controlled, so that the chip can be positioned not only in the height direction but also in a planar arrangement.

  For example, in Patent Documents 1 and 2, as an actuator capable of linear motion and rotational motion, in a piston / cylinder mechanism, a piston rod is supported by a guide flange in an axially slidable state, and the piston rod is mounted on a piston head. A configuration having a rotation driving mechanism that rotates together with the rotation mechanism is disclosed.

  Here, the guide flange has a through hole having a polygonal cross section, and its outer periphery is rotatably supported on the cylinder side via a bearing. The piston rod has the same cross-sectional shape as the polygonal through hole of the guide flange. With this structure, the piston head rotates by driving the guide flange relative to the cylinder side, and the piston head moves in the axial direction by driving the piston rod to move in the axial direction.

Japanese Patent No. 4171666 Japanese Patent No. 4268431

  In the configurations of Patent Documents 1 and 2, since the through hole of the guide flange is a polygonal through hole and the portion corresponding to the guide flange of the piston rod is a polygonal shape, complicated processing is required. Further, since the polygonal shaft moves in the axial direction in the multi-shaped hole, the linear accuracy and the rotational accuracy are limited due to friction, backlash and the like.

  An object of the present invention is to provide a fluid pressure actuator capable of accurately performing straight drive and rotational drive.

  A fluid pressure actuator capable of linearly moving and rotating according to the present invention includes a spool portion having at least one pressure receiving surface, an output shaft connected to the spool portion and extending in the axial direction of the spool portion, and the spool portion in the axial direction. An inner peripheral wall that is movably supported on the sleeve, and a sleeve portion that forms a pressure chamber in cooperation with the pressure receiving surface of the spool portion; and by supplying a fluid of a predetermined pressure to the pressure chamber, the output shaft is axially A rectilinear drive unit that is driven in a straight line, a rotating unit that is arranged coaxially with the output shaft, and that is rotatable about the axis of the output shaft, and a torsion spring body that is arranged coaxially with the output shaft and can extend and contract in the axial direction. A screw having one end fixed to the output shaft and the other end fixed to the rotating portion, and the rotation portion of the other end being rotationally driven to rotate the output shaft of the one end. And a spring body.

  Further, in the fluid pressure actuator according to the present invention, it is preferable that the torsion spring body has a low expansion / contraction rigidity in the axial direction with respect to the torsional rigidity.

  In the fluid pressure actuator according to the present invention, the torsion spring body has an inner peripheral side of one end fixed to the outer peripheral side of the output shaft, and an outer peripheral side of the other end fixed to the rotating portion. It is preferable that the output shaft goes straight through the space on the inner diameter side of the torsion spring body.

  In the fluid pressure actuator according to the present invention, the displacement sensor detects the axial displacement of the output shaft, and the axial force of the torsion spring body corresponding to the detected axial displacement is applied to the tip of the output shaft. It is preferable to provide a displacement sensor used for controlling the magnitude of the load.

  The fluid pressure actuator according to the present invention may include a pressure sensor that detects a fluid pressure supplied to the pressure chamber, and is used to control the magnitude of the load at the tip of the output shaft. preferable.

  In the fluid pressure actuator according to the present invention, the spool portion has a first pressure receiving surface and a second pressure receiving surface, and the sleeve portion cooperates with the spool portion to correspond to the first pressure receiving surface. And a second pressure chamber corresponding to the second pressure receiving surface, a fluid having a first pressure is supplied to the first pressure chamber, and a fluid having a second pressure higher than the first pressure is supplied to the second pressure chamber. Preferably, the pressure receiving area of the first pressure receiving surface is larger than the pressure receiving area of the second pressure receiving surface.

  With the above configuration, the fluid pressure actuator is supported by the sleeve portion so that the spool portion and the output shaft can move, and by supplying a fluid having a predetermined pressure to the pressure chamber formed by the cooperation of the spool portion and the sleeve portion, Drive the output shaft straight in the axial direction. In addition, the other end is fixed to the rotating portion arranged coaxially with the output shaft, and the other end rotating portion is fixed by using a torsion spring body that is fixed at one end to the output shaft and can be expanded and contracted in the axial direction. When rotated, the output shaft at one end can be rotated. The movement of the torsion spring body has no friction, so that it is possible to accurately drive straight drive and rotation.

  Further, in the fluid pressure actuator, the torsion spring body has low expansion / contraction rigidity in the axial direction with respect to the torsional rigidity, so that the accuracy of the straight drive is not lowered by the rotational drive.

  In the fluid pressure actuator, the torsion spring body has an inner diameter larger than the outer diameter of the output shaft, and the output shaft goes straight through the space on the inner diameter side of the torsion spring body. As a result, the straight drive of the output shaft is not disturbed.

  In the fluid pressure actuator, the torsion spring body has an inner peripheral side of one end fixed to the outer peripheral side of the output shaft and an outer peripheral side of the other end fixed to the rotating portion. Thereby, it is easy to maintain the coaxiality of the rotating part and the output part, and it is possible to perform straight driving and rotational driving with high accuracy.

  Further, the fluid pressure actuator includes a displacement sensor for detecting the axial displacement of the output shaft. This displacement sensor is used not only for the function of performing linear drive feedback, but also for the axial force of the torsion spring body corresponding to the detected axial displacement to control the magnitude of the load at the tip of the output shaft. It is done. Moreover, it is used for controlling the magnitude of the load at the tip of the output shaft based on the fluid pressure detected by the pressure sensor.

  In the fluid pressure actuator, the first pressure receiving surface and the second pressure receiving surface of the spool portion have a larger pressure receiving area on the first pressure receiving surface that receives a lower pressure than the pressure receiving area on the second pressure receiving surface that receives a high pressure. Thus, for example, even when a fluid having a constant high pressure is supplied to the second pressure receiving surface and a fluid having a control pressure is supplied to the first pressure receiving surface, the load at the tip of the output shaft can be changed by changing the control pressure. Can be accurately changed.

It is a figure which shows the structure of the fluid pressure actuator of embodiment which concerns on this invention. In FIG. 1, it is the elements on larger scale of the periphery of a torsion spring body. In FIG. 2, it is a figure which shows the mode of the torsion spring body when an output shaft displaces to an axial direction. In embodiment which concerns on this invention, it is a figure which shows the example of another spool part. In embodiment which concerns on this invention, it is a figure which shows the mode of the support of a spool part.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Hereinafter, a gas pressure actuator using gas will be described as the fluid pressure actuator, but a hydraulic actuator or water pressure actuator using a liquid other than gas may be used. Moreover, as gas used as a fluid, inert gas, such as nitrogen and argon other than general air and dry air, and other gas may be sufficient.

  In the following description, a coil spring will be described as the torsion spring body, but any elastic body having torsional rigidity and axial expansion / contraction rigidity may be used. It may be a continuous body in the circumferential direction like a bellows body. The material is not limited to metal, but may be plastic, rubber, plastic rubber, or the like.

  The shapes, dimensions, etc. used in the following are examples for explanation, and can be appropriately changed according to the specifications of the fluid pressure actuator. In the following description, the same elements are denoted by the same reference symbols in all the drawings, and redundant description is omitted. In the description in the text, the symbols described before are used as necessary.

  FIG. 1 is a diagram showing the configuration of the fluid pressure actuator 10. The fluid pressure actuator 10 includes a servo valve 42, and the collet 12 has a leading end using a gas having a control pressure Pc from the servo valve 42 and a gas having a supply pressure Ps supplied as an original pressure to the servo valve 42. The output shaft 18 attached to the shaft can be driven to move in the axial direction, and the output shaft 18 can be driven to rotate about the axis by a rotational drive mechanism (not shown). In FIG. 1, the axial direction of the output shaft 18 is shown as the X direction, and the rotational direction around the axis is shown as θ. The direction in which the output shaft 18 protrudes from the fluid pressure actuator 10 was defined as the + X direction.

  The fluid pressure actuator 10 is provided coaxially with the output shaft 18, the rod portion 14 including the spool portion 16 and the output shaft 18, the sleeve portion 20 that holds the spool portion 16 slidably in the axial direction, and is illustrated. A rotary part 50 connected to the rotary drive mechanism, a torsion spring body 30 having one end fixed to the output shaft 18 and the other end fixed to the rotary part 50, and an axial drive of the spool part 16 The linear drive part 40 and the displacement sensor 60 which detects the displacement of the axial direction of the output shaft 18 are comprised.

  The collet 12 is a holder that holds an electronic component chip such as a semiconductor chip. By attaching the collet 12 to the tip of the output shaft 18, for example, the semiconductor chip can be moved in the axial direction to be brought into contact with an object and a pressing load can be applied. In addition, the semiconductor chip can be appropriately rotated around the axis just before coming into contact with the object, and planar alignment with the object can be performed. Thus, by providing the collet 12, the fluid pressure actuator 10 can be used for a bonding apparatus.

  The rod portion 14 includes a spool portion 16 having a large outer diameter and an output shaft 18 that is connected to the spool portion 16 and extends in the axial direction. The spool portion 16 has a cylindrical shape with a circular cross section, and the outer diameter is finished with high accuracy. The output shaft 18 also has a cylindrical shape with a circular cross section, and its outer diameter is also finished with high accuracy. The surface on the −X side opposite to the + X side connected to the output shaft 18 of the spool portion 16 is a first pressure receiving surface 24 that receives the control pressure Pc. The surface corresponding to the step portion where the spool portion 16 is connected to the output shaft 18 is a second pressure receiving surface 28 that receives the supply pressure Ps.

  The sleeve portion 20 has an inner peripheral wall that supports the outer peripheral portion of the spool portion 16 so as to be slidable in the axial direction. The inner peripheral wall of the sleeve portion 20 has a cylindrical shape with a circular cross section, and the inner diameter thereof is finished with high accuracy so as to be slightly larger than the outer diameter of the spool portion 16. On the −X side of the sleeve portion 20, a lid portion 23 is provided so as to close and close the cylindrical shape. As a result, the first pressure chamber 22 is formed by the cooperation of the cover portion 23, the first pressure receiving surface of the spool portion 16, and the sleeve portion 20.

  The overhanging sleeve portion 21 that is a part of the sleeve portion 20 is a member having a cylindrical inner diameter that is disposed so as to cover the output shaft 18. The overhanging sleeve portion 21 supports the rotating portion 50 via a bearing 52. Therefore, the overhanging sleeve portion 21 does not contact the output shaft 18 and does not slide with the output shaft 18. The shielding member 25 provided at the end of the overhanging sleeve portion 21 on the −X side is an annular member having an inner diameter slightly larger than the outer diameter of the output shaft 18. A collar 27 is provided on the outer peripheral side of the output shaft 18 on the −X side of the shielding member 25. A second pressure chamber 26 is formed by the cooperation of the collar 27, the second pressure receiving surface 28 of the spool portion 16, and the sleeve portion 20.

  The rectilinear drive unit 40 is a gas pressure supply circuit that supplies a gas having a control pressure Pc to the first pressure chamber 22 and supplies a gas having a supply pressure Ps to the second pressure chamber 26. The rectilinear drive unit 40 generates a gas having a control pressure Pc from a gas having a supply pressure Ps supplied as a source pressure from a gas supply source (not shown), and the servo valve 42 to the first pressure chamber 22. The first gas flow path 44 for supplying a gas having a control pressure Pc to the first, the supply port 46 for supplying a gas having a supply pressure Ps separately from the supply to the servo valve 42, and the second pressure chamber 26 from the supply port 46. And a second gas channel 48 for supplying a gas having a supply pressure Ps. A gas having a supply pressure Ps may be supplied from the supply port 46 to the servo valve 42 and the second gas flow path 48 by diversion.

  Although the control pressure Pc is smaller than the supply pressure Ps, the pressure receiving area Ac of the first pressure receiving surface 24 is smaller than the pressure receiving area As of the second pressure receiving surface 28 as shown in FIG. Here, F (P) = (Pc × Ac−Ps × As) is an axial driving force of the output shaft 18 due to pressure. If the supply pressure Ps is a constant pressure, the magnitude of F (P) can be controlled by the control pressure Pc from the servo valve 42. This makes it possible to control linear drive for moving the output shaft 18 in the axial direction, and to control the magnitude of the component due to pressure in the axial load applied to the output shaft 18.

  The first gas channel 44 is provided with a pressure sensor 45 for detecting the control pressure Pc, and the second gas channel 48 is provided with a pressure sensor 49 for detecting the supply pressure Ps. The gas pressure detected by these is transmitted to a control device (not shown) and used for load control of the collet 12 at the tip of the output shaft 18.

The displacement sensor 60 is a detector that detects the axial displacement of the output shaft 18. Displacement sensor 60
A differential transformer type including a soft magnetic probe 62 and a transformer winding 64 can be used. That is, the soft magnetic probe 62 is extended along the axial direction from the −X side tip of the spool portion 16 integral with the output shaft 18 to the −X side, and the transformer winding 64 cooperating therewith is attached to the lid portion 23. Provided. The soft magnetic probe 62 is preferably aligned with the central axis of the rod portion 14. Alternatively, the center of gravity axis of the rod portion 14 and the axial center are preferably matched.

  The probe 62 is a shaft-like member composed of a nonmagnetic material fixed to the output shaft 18 and a soft magnetic material provided at the tip thereof. The probe 62 moves in the axial direction integrally with the output shaft 18, and a signal corresponding to the insertion length of the transformer winding 64 into the cavity is output from the transformer winding 64 as a displacement signal of the output shaft 18. The output displacement signal is transferred to a control device (not shown) and used for position control in the X direction of the collet 12 at the tip of the output shaft 18 of the fluid pressure actuator 10.

  As the displacement sensor 60, in addition to the differential transformer system, an optical detection type, a capacitance detection type, or a digital type position detection sensor using magnetism may be used. In addition to position control, the detected displacement may be used for speed control and acceleration control by performing an operation such as differentiation.

  Here, since the torsion spring body 30 is connected to the output shaft 18, when the output shaft 18 is displaced in the axial direction, the output shaft 18 is moved in the axial direction corresponding to the spring constant from the torsion spring body 30. Receives force F (S). The axial force F (S) by the torsion spring body 30 becomes a load as the axial force F at the collet 12 at the tip of the output shaft 18 together with the axial force F (P) due to the gas pressure. The axial force F as a load is represented by F = F (P) + F (S). F (S) is expressed as follows, where k is a spring constant in the axial direction of the torsion spring body 30, and ΔX1 is an axial displacement of the output shaft 18 with respect to the case where the torsion spring body 30 has a free length. (S) = k × (ΔX1). As described above, the output of the displacement sensor 60 is used for position control of the collet 12 at the tip of the output shaft 18 and the magnitude of the load applied to the collet 12 at the tip of the output shaft 18 is cooperated with the pressure sensors 45 and 49. It is also used to control and work.

  The rotating unit 50 is a cylindrical member that is disposed coaxially with the output shaft 18 and is rotatable around the output shaft 18. The rotating unit 50 is connected to a rotation drive mechanism (not shown) and is connected to the output shaft via the torsion spring body 30. 18 has a function of rotating around the axis.

  The torsion spring body 30 is a coil spring that is disposed coaxially with the output shaft 18, has low axial expansion / contraction rigidity with respect to the torsional rigidity, and can expand and contract in the axial direction. The torsion spring body 30 is fixed to the output shaft 18 on the inner peripheral side of the one end 32 in the −X axis direction, and is fixed to the rotating unit 50 on the outer peripheral side of the other end 34 in the + X axis direction.

  2 and 3 are enlarged detailed views around the torsion spring body 30 and the rotating portion 50. FIG. FIG. 2 shows a state where the output shaft 18 is at the right end position in the + X direction, and FIG. 3 shows a state where the output shaft 18 is displaced from the right end position in the −X direction by (−ΔX). In any case, if the torsion spring body 30 is displaced by ΔX1 from its free length, the axial force F (S) by the torsion spring body 30 is given by F (S) = k × ΔX1. It is done.

  As shown in FIGS. 2 and 3, the rotating portion 50 is attached to the overhanging sleeve portion 21 by a bearing 52 at an annular outer peripheral portion. The bearings 52 are rolling bearings and are provided in two rows in parallel along the axial direction. Two or more rows may be provided. Instead of the rolling bearing, a sliding bearing or a hydrostatic bearing may be used. The annular inner peripheral side of the rotating part 50 extends in the axial direction with a clearance from the outer periphery of the torsion spring body 30. The end on the −X side faces the + X side end on the outer peripheral side of the one end 32 of the torsion spring body 30, and when the torsion spring body 30 has a free length, The end is abutted against the + X side end of one end 32 of the torsion spring body 30. The inner peripheral side of the rotating part 50 extends in the axial direction with a gap from the outer periphery of the torsion spring body 30. The + X side end of the rotating portion 50 faces the + X side end on the outer peripheral side of the other end 34 of the torsion spring body 30 and is connected via a fixing screw 54.

  The torsion spring body 30 has one end 32 fixed to the outer peripheral side of the output shaft 18 by the crimping portion 19, the other end 34 fixed to the inner peripheral side of the rotating portion 50 via a fixing screw 54, A coil spring portion 36 between the end 32 and the other end 34 is included. As a fixing means between the one end 32 and the output shaft 18, in addition to the caulking portion 19, adhesion or a screw can be used.

  The coil spring portion 36 is formed by winding a flat spring material having a rectangular parallelepiped section with a predetermined number of turns in a spiral shape, and setting the direction in which the spiral advances as the axial direction of the spring to match the axial direction of the output shaft 18, It is arranged on the outer peripheral side of the shaft 18. An end portion in the −X direction of the coil spring portion 36 is connected to one end 32 of the torsion spring body 30, and an end portion in the + X direction is connected to the other end 34 of the torsion spring body 30. The inner diameter of the coil spring portion 36 is set to be larger than the outer diameter of the output shaft 18. Accordingly, the output shaft 18 can move straight along the axial direction in the space on the inner diameter side of the coil spring portion 36 without contacting the inner peripheral side of the coil spring portion 36.

  The short side of the rectangular parallelepiped shape of the cross section of the coil spring portion 36 is a side along the axial direction of the spring, and the long side is a side along the radial direction of the spring. Thus, by setting the thin plate thickness direction of the flat spring material as the axial direction of the coil spring portion 36, the coil spring portion 36 can have a characteristic that the expansion / contraction rigidity in the axial direction is lower than the torsional rigidity. As a result, when the output shaft 18 is displaced in the axial direction, unnecessary twisting does not occur. Further, when the output shaft 18 is rotated via the torsion spring body 30 by the rotation of the rotating portion 50, no extra axial expansion or contraction occurs.

  As described above, the coil spring portion 36 is disposed so as not to contact the outer peripheral side of the output shaft 18, and the rotating portion 50 is disposed so as not to contact the outer peripheral side of the coil spring portion 36. That is, from the inner diameter side, the output shaft 18, the coil spring portion 36, and the rotating portion 50 are arranged coaxially and concentrically so as to overlap in a triple structure. With this arrangement, when the rotating unit 50 is rotated around the axis by a rotation driving unit (not shown), the output shaft 18 rotates around the axis without friction. That is, when the rotating portion 50 rotates around the axis, the other end 34 of the torsion spring body 30 rotates integrally with the rotating portion 50, and the coil spring portion 36 does not expand and contract in the axial direction and twists its rotation. The torque is transmitted to one end 32 of the torsion spring body 30, and the output shaft 18 rotates about the axis integrally with the one end 32 of the torsion spring body 30.

  FIG. 3 is a diagram illustrating a state where the output shaft 18 is displaced by −ΔX in the axial direction by the linear drive unit 40. In response to this -ΔX displacement, the torsion spring body 30 extends by + ΔX from the right end position in FIG. At this time, if the torsion spring body 30 is deformed by ΔX1 = (ΔX−Δx) with reference to the free length, the output shaft 18 has F (S) = k × (ΔX1) = k × (ΔX−Δx). ) Axial force change F (S). Δx is a size in which the torsion spring body 30 has already been displaced from the free length before the displacement of −ΔX. Therefore, a load is applied to the collet 12 at the tip of the output shaft 18 within a range of F = F (P) −F (S). Even in this state, if the rotating unit 50 is rotated around the axis, the output shaft 18 rotates around the axis. That is, the output shaft 18 can be driven independently for straight advancement and rotation.

  In the above, the spool portion 16 has the first pressure receiving surface 24 and the second pressure receiving surface 28, the control pressure Pc from the servo valve 42 is applied to the first pressure receiving surface 24, and the supply pressure Ps is applied to the second pressure receiving surface 28. Explained as giving. FIG. 4 is a diagram illustrating the fluid pressure actuator 11 in which the second pressure receiving surface 28 is omitted and only the control pressure Pc from the servo valve 42 is applied to the first pressure receiving surface 24. Here, the rectilinear drive part 41 is comprised by the 1st gas flow path 44 which supplies the gas which has the supply pressure Ps to the 1st pressure chamber 22 from the servo valve 42 and the servo valve 42. FIG. The rod portion 15 is composed of a spool portion 17 and an output shaft 18 whose shaft diameters are hardly changed. By doing in this way, the structure of the rectilinear drive part 41 and the rod part 15 can be simplified.

  In the fluid pressure actuator 11, the load applied to the collet 12 at the tip of the output shaft 18 is F = F (P) −F (S) = (Pc × Ac) −F (S). Ac is a pressure receiving area of the first pressure receiving surface 24, and F (S) is an axial force applied to the output shaft 18 by the torsion spring body 30.

  In the above description, the spool portion 16 is held by the inner wall surface of the sleeve portion 20 so as to be slidable in the axial direction. However, a non-contact type can be achieved by using a hydrostatic bearing mechanism, and friction can be reduced. FIG. 5 is a diagram showing a configuration in which the spool portion 17 is supported by the sleeve portion 20 so as to be movable in the axial direction through a hydrostatic bearing mechanism, taking the fluid pressure actuator 11 of FIG. 4 as an example.

  Here, a supply port 70 for supplying a gas having a supply pressure Ps is provided in the lid portion 23 and connected to a decompression port 72 connected to a decompression device such as a vacuum pump (not shown) and an exhaust device (not shown). The exhaust port 74 is provided in the sleeve portion 20. Then, a static pressure bearing recess 90, an exhaust recess 94, a decompression recess 92, an exhaust recess 95, and a static pressure bearing recess 91 are sequentially formed on the outer peripheral portion of the spool portion 17 from the −X direction to the + X direction along the axial direction. Is placed. Each of these recesses is provided as an annular groove that goes around along the circumferential direction of the spool portion 17.

  The sleeve portion 20 is provided with a hydrostatic bearing flow path 80 from the supply port 70 toward the hydrostatic bearing recess 90 of the spool portion 17. Similarly, the sleeve portion 20 is provided with a pressure reducing flow path from the pressure reducing port 72 toward the pressure reducing depression 92 of the spool portion 17, and the exhaust flow path is provided from the exhaust port 74 toward the exhaust depression 94 of the spool portion 17. Provided.

  The spool portion 17 is provided with a static pressure communication passage 81 that communicates the two static pressure bearing recesses 90 and 91, and an exhaust communication passage 84 that communicates the two exhaust recesses 94 and 95. Further, a vacuum communication path 82 is provided in the spool portion 17, the output shaft, and the collet 12 along the axial direction from the vacuum recess 92 toward the collet 12. The vacuum communication path 82 opens at the end face of the collet 12 and becomes a chip suction hole 76.

  Here, a gas having a supply pressure Ps supplied from the supply port 70 is used as a static pressure bearing gas, and a gap between the inner wall surface of the sleeve portion 20 and the static pressure bearing recesses 94 and 95 of the spool portion 17 is used. To supply. As a result, the spool portion 17 floats with respect to the sleeve portion 20 by the action of the hydrostatic bearing. By this floating, the spool portion 17 can be supported by the sleeve portion 20 in a non-contact manner and movable in the axial direction. Of course, the spool portion 17 is non-contact type and can rotate around the axis. The gas used as the hydrostatic bearing is discharged to the outside through the exhaust port 74 and the decompression port 72.

  FIG. 5 is an example in which a hydrostatic bearing mechanism is provided in the fluid pressure actuator 11 of FIG. 4. Similarly, for the fluid pressure actuator 10 of FIG. 1, between the spool portion 16 and the sleeve portion 20, and A static pressure bearing mechanism can be provided in the decompression communication path 81 and the vacuum communication path 82.

  The fluid pressure actuator according to the present invention can be used in a bonding apparatus or the like.

  10, 11 Fluid pressure actuator, 12 Collet, 14, 15 Rod portion, 16, 17 Spool portion, 18 Output shaft, 19 Caulking portion, 20 Sleeve portion, 21 Overhang sleeve portion, 22 First pressure chamber, 23 Lid portion, 24 first pressure receiving surface, 25 shielding member, 26 second pressure chamber, 27 collar, 28 second pressure receiving surface, 30 torsion spring body, 32 one end, 34 other end, 36 coil spring portion, 40, 41 straight drive unit , 42 Servo valve, 44 1st gas flow path, 45, 49 Pressure sensor, 46 Supply port, 48 2nd gas flow path, 50 Rotating part, 52 Bearing, 54 Fixing screw, 60 Displacement sensor, 62 Probe, 64 Transformer winding Wire, 70 supply port, 72 pressure reducing port, 74 exhaust port, 76 tip suction hole, 80 hydrostatic bearing flow path, 81 hydrostatic communication path, 82 vacuum communication Passage, 84 Exhaust communication passage, 90,91 Hydrostatic bearing recess, 92 Depressurization recess, 94,95 Exhaust recess.

Claims (6)

A spool portion having at least one pressure receiving surface;
An output shaft connected to the spool portion and extending in the axial direction of the spool portion;
A sleeve portion having an inner peripheral wall supporting the spool portion so as to be movable in the axial direction, and forming a pressure chamber in cooperation with a pressure receiving surface of the spool portion;
A rectilinear drive unit that linearly drives the output shaft in the axial direction by supplying a fluid of a predetermined pressure to the pressure chamber;
A rotating part arranged coaxially with the output shaft and rotatable around the axis of the output shaft;
A torsion spring body that is coaxially arranged with the output shaft and is capable of expanding and contracting in the axial direction, having one end fixed to the output shaft and the other end fixed to the rotating portion, and rotation of the other end A torsion spring body in which the output shaft at one end is rotationally driven by rotating the part;
A fluid pressure actuator capable of going straight and rotating. The fluid pressure actuator according to claim 1,
The torsion spring body has a low axial expansion / contraction rigidity with respect to torsional rigidity. The fluid pressure actuator according to claim 2,
The torsion spring body
The inner peripheral side of one end is fixed to the outer peripheral side of the output shaft, and the outer peripheral side of the other end is fixed to the rotating part.
A fluid pressure actuator characterized by having an inner diameter larger than the outer diameter of the output shaft, and the output shaft goes straight through the space on the inner diameter side of the torsion spring body. The fluid pressure actuator according to claim 1,
A displacement sensor for detecting the axial displacement of the output shaft, wherein the axial force of the torsion spring body according to the detected axial displacement is used to control the magnitude of the load at the tip of the output shaft. A fluid pressure actuator comprising a displacement sensor. The fluid pressure actuator according to claim 1,
A fluid pressure actuator for detecting a fluid pressure supplied to a pressure chamber, the pressure sensor being used for controlling the magnitude of a load at a tip of an output shaft. The fluid pressure actuator according to claim 1,
The spool portion has a first pressure receiving surface and a second pressure receiving surface, and the sleeve portion cooperates with the spool portion to form a first pressure chamber corresponding to the first pressure receiving surface and a second pressure corresponding to the second pressure receiving surface. A fluid having a first pressure is supplied to the first pressure chamber, a fluid having a second pressure higher than the first pressure is supplied to the second pressure chamber, and a pressure receiving area of the first pressure receiving surface is increased. A fluid pressure actuator characterized by being wider than the pressure receiving area of the second pressure receiving surface.

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