JP2022050968A - Actuator - Google Patents

Abstract

To provide an actuator which enables a work shaft to move at high speed even if a movable stroke of the work shaft is increased.SOLUTION: An actuator 10 includes a ball screw 40, a slide part 31, a rod 11, and a first middle support unit 60. The ball screw 40 has a ball screw shaft 41 which moves in a rotating manner with rotary motion of a rotary shaft of a motor (a motor unit). The slide part 31 linearly moves in conjunction with rotary motion of the ball screw shaft 41. The rod 11 is connected to the slide part 31 so as to move linearly with the slide part 31 and formed with a hole for inserting a tip part at one side of the ball screw shaft 41 thereinto. The first middle support unit 60 is provided between a base end part at the other side of the ball screw shaft 41 and the slide part 31 so as to be slidable on the ball screw shaft 41 and supports the ball screw shaft 41.SELECTED DRAWING: Figure 4

Description

The present invention relates to an actuator.

In Patent Document 1, the ball screw shaft rotates with the rotation of the rotation shaft of the motor, and the ball screw nut screwed to the ball screw shaft with the rotation of the ball screw shaft is a rod (working shaft). A rod type actuator that moves forward and backward together with the screw is disclosed.

Japanese Unexamined Patent Publication No. 2013-36606

In the actuator described in Patent Document 1, it is desired by the user to lengthen the stroke, which is the range in which the working axis can be moved forward and backward, depending on the method of use and the installation location. However, in the case described in Patent Document 1, the length of the ball screw shaft can be extended to increase the stroke of the working shaft. In this case, the ball screw shaft bends, that is, the so-called "skipping rope phenomenon". May cause. Then, the "critical speed" of the actuator, which is a rotation speed that causes a dangerous state such as damaging the ball screw shaft, is lowered, and it may be difficult to drive the actuator at high speed.

The present invention has been made under the above circumstances, and an object of the present invention is to provide an actuator capable of moving the work axis at high speed even when the movable stroke of the work axis is lengthened.

In order to achieve the above object, the actuator according to the present invention is
A ball screw having a ball screw shaft that rotates with the rotational movement of the rotary shaft of the motor,
A slide portion that linearly moves with the rotational movement of the ball screw shaft,
A working shaft that is connected to the slide portion so as to move linearly with the slide portion and has a hole for inserting one tip of the ball screw shaft.
A first intermediate support unit that is slidably provided on the ball screw shaft and supports the ball screw shaft between the other base end portion of the ball screw shaft and the slide portion.
To prepare for.

A second intermediate support unit provided on the outer periphery of the work shaft between the tip portion and the slide portion of the ball screw shaft, and
A connecting member that connects the first intermediate support unit and the second intermediate support unit,
Equipped with
The first intermediate support unit moves linearly with the slide portion by causing the slide portion to come into contact with either the first intermediate support unit or the second intermediate support unit as the slide portion moves linearly. It may be provided as possible.

The connecting member may connect the first intermediate support unit and the second intermediate support unit outside the slide portion.

A hole for a connecting member that penetrates the ball screw shaft in the axial direction is formed in the slide portion.
The connecting member may be inserted into the connecting member hole.

The second intermediate support unit may have a sliding portion that slides on the outer peripheral surface of the work shaft.

The sliding portion may be made of a material having lubricity and may have a cylindrical portion having a through hole through which the working shaft is inserted.

The second intermediate support unit may be provided at the extended tip of the connecting member and may have a contact portion that abuts on the surface of the slide portion on the tip end side.

The contact portion of the second intermediate support unit has a flange-shaped portion that projects from the tip of the connecting member in a direction orthogonal to the extending direction and abuts on the surface of the slide portion on the tip end side. It may be formed.

A screw is formed at the tip of the connecting member.
The contact portion may be formed by a part of a fastener screwed into the screw.

The first intermediate support unit and the second intermediate support unit are connected to each other, and a second connecting member extending in parallel with the extending direction of the connecting member is provided.
The contact portion of the second intermediate support unit may be provided by connecting the extended tip of the connecting member and the extended tip of the second connecting member.

The second intermediate support unit may have a sliding portion that is arranged between the contact portion and the outer periphery of the work shaft and slides on the outer peripheral surface of the work shaft.

The second intermediate support unit is arranged between the contact portion and the outer circumference of the work shaft, and has a first rolling portion that rolls between the contact portion and the outer circumference of the work shaft. May be.

With a cover covering the work axis,
The second intermediate support unit may have a second rolling portion that is arranged between the abutting portion and the cover and rolls between the abutting portion and the cover.

A base end support portion that supports the base end portion of the ball screw shaft, and a base end support portion,
A first elastic member made of an elastic material, which is installed between the first intermediate support unit and the base end support portion,
A second elastic member made of an elastic material, which is installed between the slide portion and the first intermediate support unit,
May be provided.

The first elastic member and the second elastic member are elastically deformed when the slide portion moves linearly, so that the base end support portion is connected to the first elastic member at the first position. The slide portion may be provided so as to move the first intermediate support unit to an intermediate position between the slide portion and the second position connected to the second elastic member.

The ball screw shaft is slidably provided between the other base end portion of the ball screw shaft and the slide portion, and is provided closer to the base end portion than the first intermediate support unit. A third intermediate support unit that supports the ball screw shaft may be provided.

The ball screw shaft is slidably provided between the other base end portion of the ball screw shaft and the slide portion, and is provided closer to the base end portion than the first intermediate support unit. The third intermediate support unit that supports the ball screw shaft and
Between the tip portion and the slide portion of the ball screw shaft, a fourth intermediate support unit provided on the outer periphery of the work shaft and closer to the tip portion than the second intermediate support unit. ,
A third connecting member that connects the third intermediate support unit and the fourth intermediate support unit,
May be provided.

It may be provided with a steady rest member installed at the tip of the ball screw shaft and in contact with the inner peripheral surface of the hole of the work shaft to support the tip of the ball screw shaft.

The actuator according to the present invention includes a first intermediate support unit slidably provided on the ball screw shaft between the other base end portion and the slide portion of the ball screw shaft. The first intermediate support unit supports the ball screw shaft. Therefore, the ball screw shaft is prevented from bending. This makes it possible to provide an actuator capable of moving the work axis at high speed even when the movable stroke of the work axis of the actuator is lengthened in the present invention.

It is a perspective view of the actuator which concerns on Embodiment 1 of this invention. It is an exploded perspective view of the actuator which concerns on Embodiment 1. FIG. It is an exploded sectional view of the actuator which concerns on Embodiment 1. FIG. FIG. 5 is an enlarged perspective view showing a main part of the actuator according to the first embodiment. FIG. 5 is an exploded cross-sectional view showing a part of the actuator according to the first embodiment in a simplified manner. It is a perspective view (the 1) of the 1st intermediate support unit and the 2nd intermediate support unit. It is a front view of the 1st intermediate support unit. It is a perspective view (the 2) of the 1st intermediate support unit and the 2nd intermediate support unit. It is sectional drawing (the 1) for demonstrating the operation of the actuator which concerns on Embodiment 1. FIG. FIG. 2 is a cross-sectional view (No. 2) for explaining the operation of the actuator according to the first embodiment. FIG. 3 is a cross-sectional view (No. 3) for explaining the operation of the actuator according to the first embodiment. It is a perspective view (the 1) for demonstrating the maintenance work of the actuator which concerns on Embodiment 1. FIG. FIG. 2 is a perspective view (No. 2) for explaining the maintenance work of the actuator according to the first embodiment. It is sectional drawing of the actuator which concerns on a comparative example. It is a perspective view of the actuator which concerns on Embodiment 2. FIG. It is a perspective view of the actuator which concerns on Embodiment 3. FIG. It is a perspective view of the actuator which concerns on Embodiment 4. FIG. It is a front view of the slide part and the contact part of the actuator which concerns on Embodiment 4. FIG. It is a front view of the slide part and the contact part of the actuator which concerns on Embodiment 5. FIG. It is a front view of the slide part and the contact part of the actuator which concerns on Embodiment 6. It is sectional drawing of the actuator which concerns on Embodiment 7. It is sectional drawing of the actuator which concerns on modification 1. FIG. It is a perspective view of the 1st to 4th intermediate support units which concerns on modification 2. FIG.

Embodiment 1.
Hereinafter, the actuator 10 according to the first embodiment of the present invention will be described. As shown in FIG. 1, the Y-axis direction in the figure is a direction parallel to the moving direction D1 in which the rod 11 advances and retreats, and the X-axis direction and the Z-axis direction are directions orthogonal to the moving direction D1. .. The XY plane in the figure is a horizontal plane parallel to the plane on which the actuator 10 is installed.

As shown in FIG. 1, the actuator 10 is a rod-type linear actuator having a rod 11 (working axis) that reciprocates in the Y-axis direction. The actuator 10 is an actuator having a relatively long stroke (length in the Y-axis direction), which is the moving distance of the rod 11. The actuator 10 includes a rod 11 (working shaft), a motor unit 20, a front bracket 90, a rear bracket 100 (base end support portion), and a cover 18.

As shown in FIGS. 2 and 3, the cover 18 is a frame cover formed by, for example, extrusion molding of aluminum. However, the material and forming method of the cover 18 are not limited to this. The cover 18 may be something other than that formed by extrusion molding aluminum. The cover 18 is attached to and fixed to the front bracket 90 and the rear bracket 100 from the + Z side by fasteners 19 such as screws and bolts.

As shown in FIGS. 4 and 5, in addition to the above-mentioned rod 11 and the like, the actuator 10 includes a guide device 30 for guiding the rod 11 in the Y-axis direction, a ball screw 40, a steady rest member 50, and a first. It includes an intermediate support unit 60, a second intermediate support unit 70, a connecting member 81, and a connecting member 82 (second connecting member).

As shown in FIG. 5, the rod 11 (working shaft) is a cylindrical member having a hole 11a formed inside. The rod 11 is made of, for example, stainless steel. However, the material of the rod 11 is not limited to this. The material of the rod 11 may be other than stainless steel. The hole 11a of the rod 11 is formed so that the XZ cross section is a circular hole having a substantially perfect circle. The rod 11 has a tip fitting 12 screwed and fixed to the tip portion on the −Y side thereof. The tip metal fitting 12 of the rod 11 has, for example, a threaded surface formed on the outer periphery thereof. Various tools are screwed and attached to the tip metal fitting 12 according to the application of the actuator 10. Further, a male screw portion 11b is formed on the outer periphery of the base end portion on the + Y side of the rod 11. Note that FIG. 5 is a simplified diagram, and in the figure, the actuator 10 is shown by omitting or simplifying a part of the members such as the connecting members 81 and 82. ..

As shown in FIG. 3, the motor unit 20 has a motor 21, a motor housing 22, and an actuator cable.

The motor 21 has, for example, an output shaft 23 (rotating shaft), a rotor, a stator, an encoder, and the like. Electric power from a power source is supplied to the motor 21 via an actuator cable. By supplying electric power to the motor 21, the rotor of the motor 21 rotates. The rotary motion of the rotor is output to the output shaft 23. A coupling 23a is attached to the output shaft 23 (see FIG. 5).

The motor housing 22 is a substantially rectangular parallelepiped case. The motor housing 22 houses the motor 21 with the tip of the output shaft 23 protruding.

As shown in FIGS. 4 and 5, the guide device 30 guides the rod 11 in both the + Y direction and the −Y direction by fixing the rod 11 to the slide portion 31. The guide device 30 has a slide portion 31, a rail portion 32, and a rolling element formed in a spherical shape. The rolling element is made of a rigid material, specifically, a steel material. A plurality of rolling elements are arranged between the slide portion 31 and the rail portion 32, and are used to smoothly move the slide portion 31 with respect to the rail portion 32.

The slide portion 31 is movably supported by the rail portion 32 in the Y-axis direction via a rolling element. The slide portion 31 is fixed to a main body made of metal, a front return member fixed to the front end surface on the −Y side of the main body with fasteners, and a fastener or the like to the rear end surface on the + Y side of the main body. It has a return member on the rear side. Inside the pair of return members, a rolling element circulation path through which the rolling element passes is formed.

The main body of the slide portion 31 is a substantially rectangular parallelepiped member having a through hole 31a penetrating in the Y direction. The main body of the slide portion 31 is made of, for example, a metal such as iron. A female screw surface 31b is formed on at least a part of the inner peripheral surface of the through hole 31a. The male threaded portion 11b of the rod 11 is screwed and fixed to the female threaded surface 31b. Further, a groove portion for rolling the rolling element is formed on the + X side side surface and the −X side side surface of the main body portion of the slide portion 31. The inner surface of the groove portion is configured as a substantially curved surface.

The rail portion 32 has a plate-shaped bottom plate portion whose longitudinal direction is the Y-axis direction and a pair of side wall portions. The rail portion 32 is formed, for example, by extruding aluminum. Grooves for rolling the rolling elements are formed on the facing surfaces of the side walls corresponding to each other. The inner surface of the groove portion is configured as a substantially curved surface. A slide portion 31 is attached to the rail portion 32 via a plurality of rolling elements. When the slide portion 31 is attached to the rail portion 32, the rolling element is sandwiched between the groove portion on the side wall of the rail portion 32 and the groove portion on the side surface of the slide portion 31. As a result, the slide portion 31 can smoothly move in the Y-axis direction with respect to the rail portion 32 based on the rolling of the rolling element.

As shown in FIGS. 3 and 5, the ball screw 40 is used to move the slide portion 31 in a linear motion by converting the rotational motion of the output shaft 23 of the motor unit 20 into a linear motion. The ball screw 40 has a ball screw shaft 41 and a ball screw nut 42.

The ball screw shaft 41 has a ball screw shaft main body whose outer peripheral surface is configured as a spiral ball screw surface and a tip portion 41a on the −Y side of the ball screw shaft 41 formed to have a smaller diameter than the ball screw shaft main body. And a base end portion 41b on the + Y side.

A steady rest member 50 is fitted in the tip portion 41a. The steady rest member 50 is prevented from coming off from the tip portion 41a by the retaining member 43. The tip portion 41a is inserted into the hole 11a of the rod 11 from the + Y side. As a result, the tip portion 41a is arranged in the hole 11a of the rod 11 together with the steady rest member 50.

A coupling 44 is attached to the base end portion 41b. The base end portion 41b is connected to the coupling 23a attached to the output shaft 23 of the motor unit 20 so as to rotate together with the output shaft 23. As a result, the rotational movement of the output shaft 23 is transmitted to the ball screw shaft 41.

The ball screw nut 42 is screwed and arranged on the outer peripheral surface of the ball screw shaft 41. The ball screw nut 42 is fitted into the ball screw shaft 41 via a rigid sphere. The ball screw nut 42 is converted into a linear motion based on the rotational motion of the ball screw shaft 41.

As shown in FIG. 5, the steady rest member 50 is installed at the tip portion 41a of the ball screw shaft 41. The steady rest member 50 is a member for suppressing the runout of the tip portion 41a of the ball screw shaft 41. The steady rest member 50 has a substantially cylindrical steady rest member main body made of resin and an elastic member 51 fitted on the outer periphery of the steady rest member main body.

The elastic member 51 is an O-ring in the first embodiment. The material of the elastic member 51 is, for example, fluororubber. The elastic member 51 having an outer diameter slightly larger than the inner diameter of the hole 11a of the rod 11 is used. As a result, when the tip portion 41a of the ball screw shaft 41 is inserted into the hole 11a of the rod 11, the elastic member 51 is slidably contacted with the inner peripheral surface of the hole 11a. When the elastic member 51 slidably contacts the inner peripheral surface of the hole 11a, the steady rest member 50 causes the runout of the tip portion 41a of the ball screw shaft 41 caused by the rotation of the output shaft 23 of the motor 21. Suppress the rotation.

In the first embodiment, the steady rest member 50 is composed of a steady rest member main body made of resin and an elastic member 51 which is an O-ring. However, it is not limited to this. The steady rest member 50 may have a structure other than these, as long as the runout of the tip portion 41a of the ball screw shaft 41 can be suppressed. For example, the steady rest member 50 may be made of a single material made of only resin, or may have another structure.

As shown in FIG. 3, the first intermediate support unit 60 is provided between the base end portion 41b of the ball screw shaft 41 and the slide portion 31. Further, since the first intermediate support unit 60 is slidably provided on the ball screw shaft 41, the first intermediate support unit 60 is provided so as to be slidable in both the + Y direction and the −Y direction along the moving direction D1. .. The first intermediate support unit 60 supports the ball screw shaft 41 between the base end portion 41b and the slide portion 31 of the ball screw shaft 41, thereby suppressing the ball screw shaft 41 from bending. As shown in FIGS. 5 and 6, the first intermediate support unit 60 includes a main body portion 61, a bush 62 (sliding portion), rollers 63a to 63c, an adjust plate 64, stoppers 65 and 66, and a pipe. It has clamp portions 67R and 67L.

The main body 61 is made of, for example, metal. As shown in FIGS. 5 and 7, the main body 61 penetrates in the Y-axis direction and has a through hole 61a through which the ball screw shaft 41 and the bush 62 are inserted. The through hole 61a is not a circular hole but is formed by cutting out a part of the outside of the main body portion 61. By passing the bush 62 fitted in the ball screw shaft 41 through this notched portion, the main body portion 61 is formed so as to be removable from the bush 62 still fitted in the outer periphery of the ball screw shaft 41. Will be done.

As shown in FIGS. 5, 6 and 8, the bush 62 is fitted and arranged in the through hole 61a of the main body 61. The bush 62 is fixed to the main body 61 by fasteners 62a such as screws and bolts. The bush 62 is composed of a cylindrical portion formed in a cylindrical shape and a flange portion formed at an end portion on the + Y side of the cylindrical portion. The bush 62 is a sliding portion formed of a lubricating material and functions as a slide bearing that slides on the outer periphery of the ball screw shaft 41. In the first embodiment, the bush 62 is arranged by being directly fitted into the through hole 61a of the main body portion 61. However, it is not limited to this. The bush 62 may be fitted and arranged in the hole of the through hole 61a via a bush holder formed of metal. That is, a cylindrical bush holder may be fitted in the through hole 61a of the main body portion 61, and the bush 62 may be fitted and arranged in the through hole formed in the bush holder. ..

As shown in FIG. 7, the roller 63a is rotatably attached to the main body 61 via the adjust plate 64 in the rotation direction R1 with the Z axis as the central axis. As shown in FIGS. 6 and 7, the rollers 63b and 63c are rotatably attached directly to the main body 61 with the Z axis as the central axis. The rollers 63a to 63c roll on the grooves of the pair of side wall portions of the rail portion 32. As a result, the first intermediate support unit 60 is movably supported by the rail portion 32 along the moving direction D1 in the same manner as the slide portion 31.

The adjust plate 64 is a member for changing the roller 63a to a first position where the roller 63a fits into the groove portion of the pair of side wall portions of the rail portion 32 and a second position where the roller 63a deviates from the groove portion. The adjust plate 64 is formed in a rectangular plate shape. The adjust plate 64 is fixed to the main body 61 by two fasteners 64a such as bolts. When changing the roller 63a from the first position to the second position in the adjust plate 64, the user loosens one of the two fasteners 64a, and then loosens the other fastener 64a. As the rotation axis, it is rotated around the rotation direction R1 with the Z axis as the central axis. As a result, as shown by the arrow X1 in FIG. 7, the roller 63a is moved to the second position away from the groove portion of the rail portion 32.

As shown in FIG. 4, the stopper 65 is provided on the side surface of the main body 61 on the −Y side. The stopper 65 is made of an elastic material, for example, nitrile rubber. However, the stopper 65 may be made of a material other than nitrile rubber. The stopper 65 is provided to absorb the impact when the first intermediate support unit 60 comes into contact with the slide portion 31. The stopper 65 is fixed to the main body 61 by fasteners such as screws and bolts.

The stopper 66 is provided on the + Y side side surface of the main body 61. The stopper 66 is made of an elastic material, for example, nitrile rubber. However, the stopper 66 may be made of a material other than nitrile rubber. The stopper 66 is provided to absorb the impact when the first intermediate support unit 60 comes into contact with the rear bracket 100. The stopper 66 is fixed to the main body 61 by fasteners such as screws and bolts.

The pipe clamp portion 67R is formed on the + X side side portion of the main body portion 61. The + Y side end of the connecting member 81 is fixed to the pipe clamp portion 67R by fastening fasteners such as screws and bolts, for example.

The pipe clamp portion 67L is formed on the side portion of the main body portion 61 on the −X side. The + Y side end of the connecting member 82 is fixed to the pipe clamp portion 67L by fastening fasteners such as screws and bolts, for example.

As shown in FIG. 3, the second intermediate support unit 70 is provided on the outer periphery of the rod 11 between the tip portion 41a of the ball screw shaft 41 and the slide portion 31. Further, the second intermediate support unit 70 is provided so as to be slidable on the outer periphery of the rod 11 so as to be movable in both the + Y direction and the −Y direction along the moving direction D1. .. As shown in FIGS. 5 and 6, the second intermediate support unit 70 has a main body portion 71, a bush 72 (sliding portion), stoppers 73 and 74, and pipe clamp portions 75R and 75L.

The main body 71 is made of, for example, metal. As shown in FIG. 5, the main body portion 71 penetrates in the Y-axis direction and has a semicircular groove 71a having a semicircular YZ cross section.

As shown in FIGS. 5, 6 and 8, the bush 72 is provided so as to be slidable on the outer periphery of the rod 11. The bush 72 is arranged in the semicircular groove 71a of the main body 71. The bush 72 is composed of a cylindrical portion having a through hole and formed in a cylindrical shape, and a flange portion 72a formed at an end portion on the + Y side of the cylindrical portion. The bush 72 is formed so that the outer diameter of the cylindrical portion thereof is substantially the same as the inner diameter of the semicircular groove 71a of the main body portion 71. The bush 72 is a sliding portion formed of a lubricating material and functions as a slide bearing that slides on the outer peripheral surface of the rod 11 by inserting the rod 11 into the through hole of the cylindrical portion.

As shown in FIG. 4, the stopper 73 is provided on the + Y side side surface of the main body 71. The stopper 73 is made of an elastic material, for example, nitrile rubber. However, the stopper 73 may be made of a material other than nitrile rubber. The stopper 73 is provided to absorb the impact when the second intermediate support unit 70 comes into contact with the slide portion 31. The stopper 73 is fixed to the main body 71 by fasteners such as screws and bolts.

The stopper 74 is provided on the side surface of the main body 71 on the −Y side. The stopper 74 is made of an elastic material, for example, nitrile rubber. However, the stopper 74 may be made of a material other than nitrile rubber. The stopper 74 is provided to absorb the impact when the second intermediate support unit 70 comes into contact with the front bracket 90 (see FIG. 3). The stopper 74 is fixed to the main body 71 while sandwiching a part of the flange portion 72a of the bush 72 by fasteners 74a such as screws and bolts.

The pipe clamp portion 75R is formed on the + X side side portion of the main body portion 71. The end portion of the connecting member 81 on the −Y side is fixed to the pipe clamp portion 75R by fastening fasteners such as screws and bolts, for example.

The pipe clamp portion 75L is formed on the side portion on the −X side of the main body portion 71. The + Y side end of the connecting member 82 is fixed to the pipe clamp portion 67L by fastening fasteners such as screws and bolts, for example.

The connecting member 81 connects the first intermediate support unit 60 and the second intermediate support unit 70 outside the slide portion 31 without penetrating the slide portion 31.

Like the connecting member 81, the connecting member 82 (second connecting member) does not penetrate the slide portion 31, but outside the slide portion 31, the first intermediate support unit 60 and the second intermediate support unit 70. And concatenate.

By connecting the connecting members 81 and 82 to connect both the first intermediate support unit 60 and the second intermediate support unit 70, the first intermediate support unit 60, together with the second intermediate support unit 70, moves in the moving direction D1. Move along. Further, the connecting members 81 and 82 connect both the first intermediate support unit 60 and the second intermediate support unit 70, so that the first intermediate support unit 60 is moved along with the linear motion of the slide portion 31. When the slide portion 31 comes into contact with any of the first and second intermediate support units 60 and 70, the slide portion 31 is provided so as to be able to move linearly together with the slide portion 31.

As shown in FIG. 3, the front bracket 90 is fixed to the −Y side of the guide device 30 by fasteners such as bolts. The front bracket 90 has a bracket main body 91 and a front cover 92 that covers the bracket main body 91. The bracket body 91 is formed by, for example, die casting. Further, a through hole 91a for passing the rod 11 is formed in the bracket main body 91, and an oilless bearing is arranged on the inner peripheral surface of the through hole 91a. The oilless bearing supports the rod 11 so as to be movable in the Y-axis direction. Further, the front cover 92 is formed by, for example, resin molding. The bracket main body 91 and the front cover 92 may be formed of a material or molding method other than the above.

The rear bracket 100 (base end support portion) is fixed to the + Y side of the guide device 30 by fasteners such as bolts. The rear bracket 100 has a bracket main body 101 and a rear cover 102 that covers the bracket main body 101. The bracket body 101 is formed by, for example, die casting. Further, the bracket main body 101 is formed with a through hole for inserting the ball screw shaft 41, and a bearing 103 is arranged on the inner peripheral surface of the through hole. The ball screw shaft 41 is rotatably supported by the bearing 103. Further, the rear cover 102 is formed by, for example, resin molding. The bracket main body 101 and the rear cover 102 may be formed of a material or molding method other than the above.

The operation of the actuator 10 configured as described above will be described with reference to the drawings.

First, by supplying power to the motor 21 of the motor unit 20, as shown in FIG. 9, the output shaft 23 of the motor 21 rotates in a predetermined direction. When the output shaft 23 rotates (normal rotation), the couplings 23a and 44 are connected to each other, so that the ball screw shaft 41 connected to the output shaft 23 is an output shaft as shown by an arrow A1 in FIG. It rotates with 23.

When the ball screw shaft 41 rotates (normal rotation), the ball screw nut 42 makes a linear motion in the −Y direction as shown by the arrow A2 in FIG. As a result, the slide portion 31 and the rod 11 make a linear motion in the −Y direction, for example. At this time, since the slide portion 31 is supported by the rail portion 32 via the rolling element, the slide portion 31 moves smoothly due to the rolling of the rolling element.

As the slide portion 31 makes a linear motion in the −Y direction, the slide portion 31 eventually comes into contact with the second intermediate support unit 70, as shown in FIG. At this time, the stopper 73 of the second intermediate support unit 70 absorbs the impact generated by the contact between the second intermediate support unit 70 and the slide portion 31.

Further, when the slide portion 31 makes a linear motion in the −Y direction, the second intermediate support unit 70 makes a linear motion in the −Y direction together with the slide portion 31 as shown by the arrow A3. Further, since the first intermediate support unit 60 is connected to the second intermediate support unit 70 by the connecting members 81 and 82, the first intermediate support unit 60 is also pulled by the second intermediate support unit 70, and the first intermediate support unit 60 is also in the second intermediate. Together with the support unit 70 and the slide portion 31, it makes a linear motion in the −Y direction. At this time, the bush 62 slides on the outer periphery of the ball screw shaft 41 so that the first intermediate support unit 60 moves smoothly with respect to the ball screw shaft 41. When the second intermediate support unit 70 makes a linear motion in the −Y direction, the slide portion 31 eventually moves to the position closest to the front bracket 90 (rod end position) and comes into contact with the front bracket 90. .. At this time, the stopper 74 of the second intermediate support unit 70 absorbs the impact generated by the contact between the second intermediate support unit 70 and the front bracket 90.

As a result, the movement of the rod 11 in the −Y direction is completed.

Next, as shown by the arrow A4 in FIG. 11, when the output shaft 23 of the motor unit 20 rotates (reverses) in the direction opposite to the predetermined direction, the ball screw shaft 41 connected to the output shaft 23 outputs. It reverses with the shaft 23.

When the ball screw shaft 41 rotates (reverses), the ball screw nut 42 makes a linear motion in the + Y direction. As a result, the slide portion 31 and the rod 11 make a linear motion in the + Y direction, for example, as shown by the arrow A5. At this time, since the slide portion 31 is supported by the rail portion 32 via the rolling element, the slide portion 31 moves smoothly due to the rolling of the rolling element.

As the slide portion 31 makes a linear motion in the + Y direction, the slide portion 31 eventually comes into contact with the first intermediate support unit 60. At this time, the stopper 65 of the first intermediate support unit 60 absorbs the impact generated by the contact between the first intermediate support unit 60 and the slide portion 31.

Further, when the slide portion 31 makes a linear motion in the + Y direction, the first intermediate support unit 60 makes a linear motion in the + Y direction together with the slide portion 31 as shown by the arrow A6. Since the second intermediate support unit 70 is connected to the first intermediate support unit 60 by the connecting members 81 and 82, it is pulled by the first intermediate support unit 60, and the second intermediate support unit 70 is also the first intermediate support unit. Together with 60 and the slide portion 31, it makes a linear motion in the + Y direction. At this time, the bush 62 slides on the outer periphery of the ball screw shaft 41 so that the first intermediate support unit 60 moves smoothly with respect to the ball screw shaft 41. When the first intermediate support unit 60 makes a linear motion in the + Y direction, the slide portion 31 eventually moves to the position closest to the rear bracket 100 (rod origin position) and comes into contact with the rear bracket 100. At this time, the stopper 66 of the first intermediate support unit 60 absorbs the impact generated by the contact between the first intermediate support unit 60 and the rear bracket 100.

As a result, the movement of the rod 11 in the + Y direction is completed.

Next, a maintenance work method in the vicinity of the first intermediate support unit 60 in the actuator 10 will be described with reference to FIGS. 7 and 12. As can be seen with reference to FIG. 7, the maintenance operator removes one of the two fasteners 64a fixing the adjust plate 64 to the main body 61. Subsequently, the operator rotates the adjust plate 64 around the rotation direction R1 with the other fastener 64a as the central axis. As a result, the operator moves the roller 63a to a second position away from the groove portion of the rail portion 32. Subsequently, as shown in FIG. 12, the operator removes the fastener 62a for fixing the main body portion 61 and the bush 62. Then, the operator removes the main body 61 and the like from the bush 62 that is still fitted on the outer circumference of the ball screw shaft 41. After that, the parts of the actuator 10 are replaced or cleaned as necessary.

Subsequently, a maintenance work method in the vicinity of the second intermediate support unit 70 will be described. As shown in FIG. 13, the operator removes the fastener 74a for fixing the bush 72 and the stopper 74 to the main body 71. Then, the operator removes the main body 71 and the like from the bush 72 that is still fitted on the outer circumference of the rod 11. After that, the parts of the actuator 10 are replaced or cleaned as necessary.

As described above, the actuator 10 according to the first embodiment slides on the ball screw shaft 41 between the base end portion 41b and the slide portion 31 of the ball screw shaft 41, as shown in FIG. It is provided with a first intermediate support unit 60 that can be provided. Since the first intermediate support unit 60 supports the ball screw shaft 41, it suppresses the ball screw shaft 41 from bending. Thereby, in the first embodiment, the rod 11 can be moved at high speed even when the movable stroke of the rod 11 of the actuator 10 is lengthened.

For example, the actuator 1000 according to the comparative example shown in FIG. 14 has a first intermediate support unit 60 slidably provided on the ball screw shaft 41 between the base end portion 41b of the ball screw shaft 41 and the slide portion 31. I don't prepare. Therefore, in the actuator 1000, the ball screw shaft 41 tends to bend. In particular, when the length of the work shaft is extended by extending the length of the ball screw shaft 41, the bending of the ball screw shaft 41 becomes large, and the so-called "skipping rope phenomenon" is likely to occur. Then, the "critical speed" of the actuator 1000, which is a rotation speed that causes a dangerous state such as damaging the ball screw shaft, is lowered, and it may be difficult to drive the actuator 1000 at high speed.

On the other hand, as shown in FIG. 3, the actuator 10 according to the first embodiment includes the first intermediate support unit 60 that supports the ball screw shaft 41, so that the ball screw shaft 41 is suppressed from bending. do. Thereby, in the first embodiment, the rod 11 can be moved at high speed even when the movable stroke of the rod 11 of the actuator 10 is lengthened.

Further, as shown in FIGS. 3 and 4, the actuator 10 further includes a second intermediate support unit 70 and connecting members 81 and 82 in addition to the first intermediate support unit 60. Then, the first intermediate support unit 60 moves linearly together with the slide portion 31 when the slide portion 31 comes into contact with any of the first and second intermediate support units 60 and 70 as the slide portion 31 moves linearly. It is provided as possible. Therefore, the first intermediate support unit 60 is arranged at a position where the distance between the first intermediate support unit 60 and the slide portion 31 is equal to or less than a predetermined distance. As a result, the actuator 10 can further improve the effect of suppressing the bending of the ball screw shaft 41. As a result, in the first embodiment, the rod 11 can be moved at high speed even when the movable stroke of the rod 11 of the actuator 10 is lengthened.

(Modified Example of Embodiment 1)
In the first embodiment, the first and second intermediate support units 60 and 70 are connected by two connecting members 81 and 82. However, it is not limited to this. The first and second intermediate support units 60 and 70 may be connected by one connecting member 81, or may be connected by three or more connecting members.

Embodiment 2.
The second intermediate support unit 70 of the actuator 10 according to the first embodiment has a bush 72 that slides on the outer peripheral surface of the rod 11. However, the second intermediate support unit 70 is not limited to that of this structure. Hereinafter, the actuator 10A according to the second embodiment in which the second intermediate support unit 70 has a different structure will be described with reference to FIG. In the actuator 10A, the same reference numerals are used for the same or equivalent configurations as the actuator 10, and the description thereof will be omitted. The actuator 10A is the same as the actuator 10 according to the first embodiment in that the second intermediate support unit 70 is provided on the outer periphery of the rod 11. However, the actuator 10A has an embodiment in that the second intermediate support unit 70 is separated from the outer peripheral surface of the rod 11 without being in close contact with the outer peripheral surface of the rod 11 and does not have a sliding portion that slides on the outer peripheral surface of the rod 11. It is different from the actuator 10 according to 1.

As shown in FIG. 15, the second intermediate support unit 70 is provided at the tip extending in the −Y direction of the connecting members 81 and 82. The second intermediate support unit 70 has a contact portion 76R provided at the tip on the −Y side of the connecting member 81, and a contact portion 76L provided at the tip on the −Y side of the connecting member 82.

The contact portion 76R is formed so as to abut on the surface of the slide portion 31 on the −Y side (the tip end side of the ball screw shaft) as the slide portion 31 moves in the −Y direction. Specifically, the contact portion 76R has a flange shape that projects from the tip of the connecting member 81 in a direction orthogonal to the extending direction (Y-axis direction) and abuts on the −Y side surface of the slide portion 31. The part is formed. A surface parallel to the −Y side surface of the slide portion 31 is formed in this flange-shaped portion, whereby the contact portion 76R is provided so as to easily abut on the −Y side surface of the slide portion 31. Has been done. In the second embodiment, the contact portion 76R is the head of a fastener such as a nut screwed into a male screw (screw) formed at the tip of the connecting member 81. This head is formed as a flange-shaped portion that abuts on the surface of the slide portion 31 on the −Y side. The contact portion 76R is not limited to this structure. The contact portion 76R may be the head of a bolt (fastener) screwed into a screw hole (screw) formed at the tip of the connecting member 81.

The contact portion 76L is formed so as to abut on the surface of the slide portion 31 on the −Y side (the tip end side of the ball screw shaft) as the slide portion 31 moves in the −Y direction. Specifically, the contact portion 76L has a flange shape that projects from the tip of the connecting member 82 in a direction orthogonal to the extending direction (Y-axis direction) and abuts on the −Y side surface of the slide portion 31. The part is formed. A surface parallel to the −Y side surface of the slide portion 31 is formed in this flange-shaped portion, whereby the contact portion 76L is provided so as to easily abut on the −Y side surface of the slide portion 31. Has been done. In the second embodiment, the contact portion 76L is the head of a fastener such as a nut screwed into a male screw formed at the tip of the connecting member 82, similarly to the contact portion 76R. This head is formed as a flange-shaped portion that abuts on the surface of the slide portion 31 on the −Y side. The contact portion 76L is not limited to this structure. The contact portion 76L may be the head of a bolt (fastener) screwed into a screw hole (screw) formed at the tip of the connecting member 82.

The slide portion 31 is formed with a hole 31c (a hole for a connecting member) that penetrates the ball screw shaft 41 in the axial direction (Y-axis direction). In the second embodiment, the slide portion 31 is different from that of the first embodiment only in that the hole 31c is formed.

The connecting members 81 and 82 are inserted through the holes 31c of the slide portion 31 to connect the first intermediate support unit 60 and the second intermediate support unit 70. The connecting members 81 and 82 may have a sliding bearing or the like arranged on the inner surface of the hole 31c of the slide portion 31 and may be slidably inserted through the inner surface of the hole 31c of the slide portion 31. It may be inserted with a gap provided from the inner surface of the hole 31c.

As described above, in the actuator 10A according to the second embodiment, the same effect as that of the actuator 10 according to the first embodiment can be obtained while the second intermediate support unit 70 has a simple structure.

Further, in the second embodiment, the connecting members 81 and 82 are inserted into the holes 31c of the slide portion 31. Therefore, the connecting members 81 and 82 have the connecting members 81 and 82 inside the actuator 10A as compared with the first embodiment in which the first and second intermediate support units 60 and 70 are connected outside the slide portion 31. There is no need to provide extra space for placement. As a result, the actuator 10A can be downsized.

Further, in the second embodiment, the connecting members 81 and 82 are inserted into the holes 31c of the slide portion 31. Therefore, in the actuator 10A, the bending of the connecting members 81 and 82 themselves can be suppressed even if the second intermediate support unit 70 does not have a sliding portion that slides on the outer peripheral surface of the rod 11.

(Modified Example of Embodiment 2)
In the second embodiment, the second intermediate support unit 70 has two contact portions 76R and 76L. However, it is not limited to this. The second intermediate support unit 70 may have one contact portion 76R or may have three or more contact portions.

Further, in the second embodiment, the connecting members 81 and 82 are inserted into the hole 31c of the slide portion 31, but the present invention is not limited to this. If the contact portions 76R and 76L are formed so as to abut on the −Y side surface of the slide portion 31 as the slide portion 31 moves in the −Y direction, the connecting members 81 and 82 slide. The first and second intermediate support units 60 and 70 may be connected to the outside of the unit 31.

Embodiment 3.
In the second intermediate support unit 70 according to the second embodiment, the contact portion 76R is arranged apart from the contact portion 76L. However, it is not limited to this. Hereinafter, the actuator 10B according to the third embodiment in which the shape of the contact portion 77 is different will be described with reference to FIG. In the actuator 10B, the same reference numerals are used for the same or equivalent configurations as the actuators 10 and 10A, and the description thereof will be omitted.

As shown in FIG. 16, the second intermediate support unit 70 is provided with a contact provided by connecting the extended −Y side tip of the connecting member 81 and the extended −Y side tip of the connecting member 82. It has a part 77.

The contact portion 77 is formed in the shape of a rectangular parallelepiped plate whose longitudinal direction is the X-axis direction. The shape of the contact portion 77 is not limited to this, and may be a shape other than a rectangular parallelepiped plate. The contact portion 77 is fixed to the tips of the connecting members 81 and 82 by fasteners 77a such as nuts.

As described above, the actuator 10A according to the third embodiment also has the same effect as the actuators 10 and 10A according to the first and second embodiments while having a simple structure for the second intermediate support unit 70. be able to.

(Modified Example of Embodiment 3)
In the third embodiment, the connecting members 81 and 82 connect the first and second intermediate support units 60 and 70 outside the slide portion 31. However, it is not limited to this. A hole penetrating in the Y-axis direction is formed in the slide portion 31, and the connecting members 81 and 82 may be inserted into the hole in the slide portion 31.

Embodiment 4.
In the second intermediate support unit 70 according to the third embodiment, no member is arranged between the contact portion 77 and the rod 11, and the second intermediate support unit 70 is separated from the rod 11. .. However, it is not limited to this. Like the actuator 10C according to the fourth embodiment shown in FIGS. 17 and 18, the second intermediate support unit 70 is arranged between the contact portion 77 and the outer periphery of the rod 11, and slides on the outer peripheral surface of the rod 11. It may have a moving sliding portion 78. The sliding portion 78 is composed of, for example, a sliding bearing having a semicircular XZ cross section. In the actuator 10C, the same reference numerals are used for the same or equivalent configurations as those of the actuators 10, 10A and 10B, and the description thereof will be omitted.

The actuator 10C according to the fourth embodiment can also have the same effect as the actuators 10, 10A and 10B according to each of the above embodiments.

Embodiment 5.
In the second intermediate support unit 70 according to the fourth embodiment, a sliding portion 78 composed of a sliding bearing is arranged between the contact portion 77 and the rod 11. However, it is not limited to this. Like the actuator 10D according to the fifth embodiment shown in FIG. 19, the second intermediate support unit 70 is arranged between the abutting portion 77 and the outer circumference of the rod 11, and is arranged with the abutting portion 77 and the outer circumference of the rod 11. It may have a rolling element 79-1 (first rolling section) that rolls between. The rolling element 79-1 is, for example, a disk-shaped roller provided so as to be rollable around the rotation direction R2 with the rotation axis A7 as the central axis. In the actuator 10D, the same reference numerals are used for the same or equivalent configurations as those of the actuators 10A to 10C, and the description thereof will be omitted.

The actuator 10D according to the fifth embodiment can also have the same effect as the actuators 10, 10A to 10C according to each of the above embodiments.

In the fifth embodiment, the rolling element 79-1 is a disk-shaped roller provided so as to be rollable around the rotation direction R2 with the rotation axis A7 as the central axis. However, it is not limited to this. The rolling element 79-1 may be a sphere.

Embodiment 6.
In the second intermediate support unit 70 according to the fourth and fifth embodiments, no member is arranged between the contact portion 77 and the cover. However, it is not limited to this. Like the actuator 10E according to the sixth embodiment shown in FIG. 20, the second intermediate support unit 70 is arranged between the abutting portion 77 and the cover 18, and rolls between the abutting portion 77 and the cover 18. It may have a moving rolling element 79-2 (second rolling section). The rolling element 79-2 is, for example, a disk-shaped roller provided so as to be rollable around the rotation direction R3 with the rotation axis A8 as the central axis. In the actuator 10E, the same reference numerals are used for the same or equivalent configurations as those of the actuators 10A to 10D, and the description thereof will be omitted.

The actuator 10E according to the sixth embodiment can also have the same effect as the actuators 10, 10A to 10D according to each of the above embodiments. Further, since the actuator 10E has the rolling element 79-2, it is possible to prevent the second intermediate support unit 70 from floating and separating from the rod 11.

In the sixth embodiment, the rolling element 79-2 is a disk-shaped roller provided so as to be rollable around the rotation direction R3 with the rotation axis A8 as the central axis. However, it is not limited to this. The rolling element 79-2 may be a sphere.

Embodiment 7.
Hereinafter, the actuator 10F according to the seventh embodiment of the present invention will be described. In the actuator 10F, the same reference numerals are used for the same or equivalent configurations as those of the actuators 10A to 10E, and the description thereof will be omitted. Further, the actuator 10F is the same as the actuator 10 except that the first elastic member 110 and the second elastic member 120 composed of coil springs are provided in place of the second intermediate support unit 70 and the connecting members 81 and 82. It has a structure.

The first elastic member 110 is made of an elastic material, specifically, a coil spring. The first elastic member 110 is installed between the first intermediate support unit 60 and the rear bracket 100. In the seventh embodiment, the first elastic member 110 is composed of a coil spring surrounding the ball screw shaft 41. However, it is not limited to this. The first elastic member 110 may be made of a material other than the coil spring as long as it is made of an elastic material. Further, the first elastic member 110 composed of the coil spring may be installed between the first intermediate support unit 60 and the rear bracket 100 so as not to surround the ball screw shaft 41. However, from the viewpoint of reducing the size of the actuator 10F, it is preferable that the first elastic member 110 is arranged so as to surround the ball screw shaft 41.

The second elastic member 120 is made of an elastic material, and specifically, like the first elastic member 110, is composed of a coil spring. The second elastic member 120 is installed between the slide portion 31 and the first intermediate support unit 60. In the seventh embodiment, the second elastic member 120 is formed so that the length in the Y-axis direction thereof is equal to the length in the Y-axis direction of the first elastic member 110. In the seventh embodiment, the second elastic member 120 is composed of a coil spring that surrounds the ball screw shaft 41. However, it is not limited to this. The second elastic member 120 may be made of a material other than the coil spring as long as it is made of an elastic material. Further, the second elastic member 120 composed of the coil spring may be installed between the slide portion 31 and the first intermediate support unit 60 so as not to surround the ball screw shaft 41. However, from the viewpoint of reducing the size of the actuator 10F, it is preferable that the second elastic member 120 is arranged so as to surround the ball screw shaft 41.

The first elastic member 110 and the second elastic member 120 have a first position P1 in which the rear bracket 100 is connected to the first elastic member 110 due to the elastic deformation of the slide portion 31 by linearly moving in the Y-axis direction. The slide portion 31 is provided so as to move the first intermediate support unit 60 to an intermediate position P3 between the second elastic member 120 and the second position P2. Therefore, regardless of whether the slide portion 31 moves in the + Y direction or the −Y direction, the first intermediate support unit 60 is arranged at the intermediate position P3 in the Y-axis direction between the first position P1 and the second position P2. Will be done.

In the actuator 10F according to the seventh embodiment, the first elastic member 110 and the second elastic member 120 have the first intermediate support unit 60 at the intermediate position P3 between the first position P1 and the second position P2. Move it. Therefore, the effect of suppressing the bending of the ball screw shaft 41 can be enhanced. As a result, the rod 11 can be moved at high speed even when the movable stroke of the rod 11 of the actuator 10F is lengthened.

In the actuator 10F according to the seventh embodiment, the second intermediate support unit 70 and the connecting members 81 and 82 can be omitted. However, it is not limited to this. The actuator 10F may further include a second intermediate support unit 70 and connecting members 81 and 82.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments.

Modification example 1.
For example, the actuator 10 according to the first embodiment includes one first intermediate support unit 60. However, it is not limited to this. As in the first modification shown in FIG. 22, the actuator 10G may further include a third intermediate support unit 130 having a structure equivalent to that of the first intermediate support unit 60 in addition to the first intermediate support unit 60. ..

The third intermediate support unit 130 is slidably provided on the ball screw shaft 41 between the other base end portion 41b of the ball screw shaft 41 and the slide portion 31, and is more base than the first intermediate support unit 60. It is provided near the end portion 41b and supports the ball screw shaft 41.

Also in the first modification, the same effect as that of each of the above embodiments can be obtained.

The actuator 10G includes two units, a first intermediate support unit 60 and a third intermediate support unit 130 having a structure equivalent to that of the first intermediate support unit 60. However, it is not limited to this. The actuator 10G may include three or more units having the same structure as the first intermediate support unit 60.

Further, in the actuator 10G, an elastic member composed of a coil spring may be installed between the first intermediate support unit 60 and the third intermediate support unit 130.

Modification example 2.
Further, as shown in FIGS. 4 and 6, the actuator 10 according to the first embodiment includes one first intermediate support unit 60 and one second intermediate support unit 70, respectively. However, it is not limited to this. As shown in the second modification shown in FIG. 23, the actuator 10H includes a third intermediate support unit 130 having a structure equivalent to that of the first intermediate support unit 60 in addition to the first and second intermediate support units 60 and 70. A fourth intermediate support unit 140 having the same structure as the second intermediate support unit 70 may be further provided. In this case, the actuator 10H includes a third connecting member 83 and a fourth connecting member 84 that connect the third intermediate support unit 130 and the fourth intermediate support unit 140.

The third intermediate support unit 130 is slidably provided on the ball screw shaft between the other base end portion and the slide portion of the ball screw shaft, and is closer to the base end portion than the first intermediate support unit 60 ( It is provided on the + Y side) and supports the ball screw shaft.

The fourth intermediate support unit 140 is provided on the outer periphery of the rod 11 between the tip of the ball screw shaft and the slide portion, and is provided closer to the tip (-Y side) than the second intermediate support unit 70. Has been done.

The third connecting member 83 and the fourth connecting member 84 connect the third intermediate support unit 130 and the fourth intermediate support unit 140.

Also in the second modification, the same effect as that of each of the above embodiments can be obtained.

The present invention allows for various embodiments and modifications without departing from the broad spirit and scope of the invention. The embodiments described above are for the purpose of explaining the present invention and do not limit the scope of the present invention.

10, 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H, 1000: Actuator 11: Rod (working shaft)
11a: Hole 11b: Male thread 12: Tip bracket 18: Cover 19: Fastener 20: Motor unit 21: Motor 22: Motor housing 23: Output shaft (rotating shaft)
23a: Coupling 30: Guide device 31: Slide part 31a: Through hole 31b: Female thread surface 31c: Hole (hole for connecting member)
32: Rail part 40: Ball screw 41: Ball screw shaft 41a: Tip part 41b: Base end part 42: Ball screw nut 43: Retaining member 44: Coupling 50: Anti-sway member 51: Elastic member 60: First middle Support unit 61: Main body 61a: Through hole 62: Bush (sliding part)
62a: Fastener 63a, 63b, 63c: Roller 64: Adjust plate 64a: Fastener 65, 66: Stopper 67R, 67L: Pipe clamp part 70: Second intermediate support unit 71: Main body part 71a: Semicircular groove 72: Bush (Sliding part)
72a: Flange part 73, 74: Stopper 74a: Fastener 75R, 75L: Pipe clamp part 76R, 76L, 77: Contact part 77a: Fastener 78: Sliding part 79-1: Rolling element (first rolling element)
79-2: Rolling body (second rolling body)
81: Connecting member 82: Connecting member (second connecting member)
83: Third connecting member 84: Fourth connecting member 90: Front bracket 91: Bracket body 91a: Through hole 92: Front cover 100: Rear bracket (base end support)
101: Bracket body 102: Rear cover 103: Bearing 110: First elastic member 120: Second elastic member 130: Third intermediate support unit 140: Fourth intermediate support unit D1: Movement direction A1, A2, A3, A4, A5 A6, X1: Arrows A7, A8: Rotation axis P1: First position P2: Second position P3: Intermediate position

Claims (18)

A ball screw having a ball screw shaft that rotates with the rotational movement of the rotary shaft of the motor,
A slide portion that linearly moves with the rotational movement of the ball screw shaft,
A working shaft that is connected to the slide portion so as to move linearly with the slide portion and has a hole for inserting one tip of the ball screw shaft.
A first intermediate support unit that is slidably provided on the ball screw shaft and supports the ball screw shaft between the other base end portion of the ball screw shaft and the slide portion.
The actuator. A second intermediate support unit provided on the outer periphery of the work shaft between the tip portion and the slide portion of the ball screw shaft, and
A connecting member that connects the first intermediate support unit and the second intermediate support unit,
Equipped with
The first intermediate support unit moves linearly with the slide portion by causing the slide portion to come into contact with either the first intermediate support unit or the second intermediate support unit as the slide portion moves linearly. The actuator according to claim 1, which is provided as possible. The actuator according to claim 2, wherein the connecting member connects the first intermediate support unit and the second intermediate support unit outside the slide portion. A hole for a connecting member that penetrates the ball screw shaft in the axial direction is formed in the slide portion.
The actuator according to claim 2, wherein the connecting member is inserted into the connecting member hole. The actuator according to any one of claims 2 to 4, wherein the second intermediate support unit has a sliding portion that slides on an outer peripheral surface of the work shaft. The actuator according to claim 5, wherein the sliding portion is made of a material having lubricity and has a cylindrical portion having a through hole through which the working shaft is inserted. The second intermediate support unit is provided in any one of claims 2 to 4, wherein the second intermediate support unit is provided at an extended tip of the connecting member and has a contact portion that abuts on a surface of the slide portion on the tip end side. Actuator. The contact portion of the second intermediate support unit has a flange-shaped portion that projects from the tip of the connecting member in a direction orthogonal to the extending direction and abuts on the surface of the slide portion on the tip end side. The actuator according to claim 7, which is formed. A screw is formed at the tip of the connecting member.
The actuator according to claim 7 or 8, wherein the contact portion is formed by a part of a fastener screwed into the screw. The first intermediate support unit and the second intermediate support unit are connected to each other, and a second connecting member extending in parallel with the extending direction of the connecting member is provided.
The actuator according to claim 7, wherein the contact portion of the second intermediate support unit is provided by connecting an extended tip of the connecting member and an extended tip of the second connecting member. The actuator according to claim 10, wherein the second intermediate support unit is arranged between the contact portion and the outer periphery of the work shaft, and has a sliding portion that slides on the outer peripheral surface of the work shaft. The second intermediate support unit is arranged between the contact portion and the outer circumference of the work shaft, and has a first rolling portion that rolls between the contact portion and the outer circumference of the work shaft. The actuator according to claim 10. With a cover covering the work axis,
11. The actuator described. A base end support portion that supports the base end portion of the ball screw shaft, and a base end support portion,
A first elastic member made of an elastic material, which is installed between the first intermediate support unit and the base end support portion,
A second elastic member made of an elastic material, which is installed between the slide portion and the first intermediate support unit,
The actuator according to any one of claims 1 to 13. The first elastic member and the second elastic member are elastically deformed when the slide portion moves linearly, so that the base end support portion is connected to the first elastic member at the first position. The actuator according to claim 14, wherein the first intermediate support unit is provided so as to move the first intermediate support unit to an intermediate position between the slide portion and the second position connected to the second elastic member. The ball screw shaft is slidably provided between the other base end portion of the ball screw shaft and the slide portion, and is provided closer to the base end portion than the first intermediate support unit. The actuator according to any one of claims 1 to 13, further comprising a third intermediate support unit that supports the ball screw shaft. The ball screw shaft is slidably provided between the other base end portion of the ball screw shaft and the slide portion, and is provided closer to the base end portion than the first intermediate support unit. The third intermediate support unit that supports the ball screw shaft and
Between the tip portion and the slide portion of the ball screw shaft, a fourth intermediate support unit provided on the outer periphery of the work shaft and closer to the tip portion than the second intermediate support unit. ,
A third connecting member that connects the third intermediate support unit and the fourth intermediate support unit,
The actuator according to any one of claims 2 to 13. 17. The actuator according to any one item.

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