JPH075953Y2 - Cam mechanism - Google Patents

Description

TECHNICAL FIELD The present invention relates to a torsion spring mounting machine that is preferably implemented when mounting a torsion spring at a predetermined position such as a chassis.

2. Description of the Related Art Conventionally, the work of mounting a torsion spring at a predetermined position such as a chassis has been performed manually by using a tool such as a pin set as shown below. The shaft provided in the chassis or the like is inserted into the insertion opening formed in the facing surface of a member such as a U-shaped bent metal plate. At this time, a torsion spring is inserted around the axis between the facing surfaces of a member such as a metal plate. One end of the torsion spring is locked by a locking protrusion formed on the member. The operator sandwiches the other end of the torsion spring with a tool such as a pin set and angularly displaces it against the spring force of the torsion spring. The chassis is provided with a locking projection at a predetermined locking position where the other end of the torsion spring is to be locked, and the other end of the torsion spring is locked to the locking projection. In this way, the torsion spring is attached to the chassis.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention In the above-mentioned conventional technique, the other end of the torsion spring must be angularly displaced against the spring force beyond the locking projection provided on the chassis. Therefore, the other end of the torsion spring must be displaced while avoiding contact with the side opposite to the side that is locked by the locking projection, and must also be displaced in the axial direction of the torsion spring. . This kind of work requires skill,
Especially when a torsion spring having a strong spring force is used, the work is extremely difficult and requires a long time.

Another prior art for automating this work is disclosed in JP-A-60
-221226. This prior art is equipped with three air cylinders and two rotary reactors in order to realize the complicated operation when mounting the above-mentioned torsion spring, and there is a big problem that it is necessary to control complicated timing. is there.

Another prior art is disclosed in JP-A-61-121843.
This prior art does not disclose a specific configuration of the drive source for mounting the torsion spring, and does not include any device for simplifying the configuration.

An object of the present invention is to provide a cam mechanism capable of realizing a complicated operation of a torsion spring mounting machine or the like with a simple structure.

MEANS FOR SOLVING THE PROBLEMS The present invention includes a shaft 6, a main body 25 that rotatably supports the shaft 6, and rotary reactor means 2 to 5 provided on the main body 25 to drive the shaft 6 in an angular displacement manner. A support member 12 through which the shaft 6 is inserted, is displaceable in the axial direction of the shaft 6, and is angularly displaced together with the shaft 6 in the rotation direction of the shaft 6.
A working member 13 provided on the support member 12 and extending to one end side of the shaft 6 for performing work; and a spring for applying a spring force to the support member 12 on the other end side of the shaft 6.
15, the shaft 6 is inserted, and the shaft 6 is inserted in the axial direction of the shaft 6 rather than the support member 12.
An angular displacement member 7 rotatably provided around the shaft 6 on the other end side of the shaft 6 and a cam means, the cam means facing the axial direction of the shaft 6 and having an axial position in the circumferential direction. Changing cam surface 9
And a follower 10 opposed to the cam surface 9, which is interposed between the angular displacement member 7 and the support member 12. The spring 15 presses the cam surface 9 and the follower 10 together. , Either one (8 or 10) is attached to the angular displacement member 7,
One of the other (10 or 8) is attached to the support member 12, and the main body 25 is provided with one end and the other end is connected to the angular displacement member 7 to expand and contract to angularly displace the angular displacement member 7. A cam mechanism including cylinder means 18 to 24, 28 which are driven to change the relative positions of the angular displacement member 7 and the support member 12.

Operation According to the present invention, the main body 25 such as the main body of the spring mounting machine supports the shaft 6 which is driven to be angularly displaced by the rotary actuator means 2 to 5, and the support member 6 is the shaft 6. Is axially displaceable, and is angularly displaced together with the shaft 6 in the rotation direction of the shaft 6, and the support member 12 is supported by the spring 15 on the other end side of the shaft 6 (see FIG. 3, which will be described later). (In the example above)
Is provided with a spring force, and an angular displacement member 7 is provided rotatably around the shaft 6 so as to be angularly displaced and driven by the cylinder means 18 to 24, 28. A cam means is interposed therebetween, and either one of the cam 8 and the follower 10 of the cam means is attached to the angular displacement member 7, and the other of the cam 8 and the follower 10 is attached to the support member 12. Therefore, the support member 12 is angularly displaced by the rotary actuator means 2 to 5 and is provided on the support member 12, for example, the end portion 43 of the torsion spring 41.
Working member 13 that performs work such as a locking pin that locks
Is angularly displaced, and the angular displacement member 7 is angularly driven by the expansion / contraction drive of the cylinder means 18-24, 28, whereby the cam 8 of the cam means attached to the angular displacement member 7 or One of the above-mentioned ones of the Hollow 10 is angularly displaced,
As a result, the other one displaces the support member 12 in the axial direction of the shaft 6, and thus the working member 13 is displaced in the axial direction of the shaft 6. In such a configuration, the rotary actuator means 2-5 and the cylinder means 18-24, 28 are provided,
It is easy to perform the operation of the working member 13 at the timing of those operations, so that the relatively complicated operation of the working member 13 can be realized with a simple configuration.

Embodiment FIG. 1 is a perspective view showing a partial configuration of a torsion spring mounting machine 1 provided with a cam mechanism according to an embodiment of the present invention. The torsion spring mounting machine 1 has a rotary actuator 2 and gears 4,5.
A cylinder 24, a drive piece 18, an angular displacement member 7, an end piece cam 8, a support member 12, and a pin 13. The rotary actuator 2 angularly displaces the output shaft 3 by, for example, air pressure. The output shaft 3 of this rotary actuator 2 is connected to a gear 4 which meshes with a gear 5. The rotary actuator 2 and the gears 4 and 5 constitute an angular displacement driving means.

The gear 5 is fixed to the shaft 6, and the output shaft 3 of the rotary reactor 2 is angularly displaced, so that the shaft 6 is also angularly displaced in conjunction.

The support member 12 is supported so as to be displaceable in the longitudinal direction of the shaft 6, that is, the axial direction, and to be angularly displaced together with the shaft 6 in the rotation direction of the shaft 6, and a pin 13 is fixed below the support member 12 in FIG. A recess 14 is formed at the end of the pin 13 for locking the end of a torsion spring described later. In this way, the motive power is output by the angular displacement of the rotary actuator 2 to the output shaft 3 and the gear.
It is transmitted to the support member 12 via the shafts 6 and 4, and the pin 1
3 is angularly displaced.

Direction or arrow indicated by arrow 33 for cylinder 24
The piston rod 23 displaceable in the direction indicated by 34 is a drive piece 18
Connected to. The drive piece 18 has slots 19, 20 and notches 21,
22 is formed. For example, a protrusion 28 formed on the angular displacement member 7 is loosely inserted in the notch 22.

The angular displacement member 7 is supported by a bearing 16 so as to be angularly displaceable with the shaft 6, and the end piece cam 8 is provided at the lower portion of the angular displacement member 7 in FIG.
Is fixed. The roller 11 of the follower 10 fixed to the support member 12 is in contact with the cam surface 9 of the end piece cam 8.
The support member 12 is spring-biased upward in FIG. 1 by a spring 15, whereby the roller 11 is pressed against the cam surface 9.

The angular displacement member 7 is fixed to the angular displacement member 7 by the displacement of the drive piece 18 connected to the piston rod 23 in this way with respect to the cylinder 24 in the direction indicated by the arrow 33 or the arrow 34. The end piece cam 8 is angularly displaced. End piece cam 8
1. The contact position between the cam surface 9 having a step and the roller 11 which will be described later is displaced in accordance with the angular displacement of the support member 12, whereby the support member 12 is displaced in the vertical direction in FIG. Is displaced to.

FIG. 2 is a diagram for explaining the operation of the pin 13. First, the entire main portion of the torsion spring mounting machine 1 including the pin 13 is displaced in the direction indicated by the arrow 61 by the elevator 40 described later, and stopped at a predetermined position. The output shaft 3 is then angularly displaced by the rotary actuator 2, which causes the pin 13 to be displaced as indicated by the arrow 62. At this time, since the roller 11 moves along the cam surface 9, the pin 13 also moves in the axial direction. The drive piece 18 is then displaced relative to the cylinder 24 in the direction indicated by the arrow 34 in FIG. 1, whereby the pin 13 is displaced axially as indicated by the arrow 63. After this, the rotary actuator 2 is driven to rotate again,
This causes the pin 13 to be displaced as indicated by arrow 64. During the displacement indicated by the arrow 64, the end of the torsion spring locked to the pin 13 is locked to the locking piece 30 fixed to the chassis or the like. After this, the drive piece 18 is displaced in the direction indicated by the arrow 33 and returns to the original position. At this time, the pin 13 is not displaced. Finally, the lifter 40, which will be described later, allows the pin 13
The main part of the torsion spring mounting machine 1 including is displaced in the direction indicated by the arrow 65.

FIG. 3 is a sectional view showing the configuration of the main part of the torsion spring mounting machine 1. A lever 35 is fixed to the upper part of the output shaft 3 of the rotary actuator 2, and the lever 35 is attached to the stopper 36.
By contacting with, the displacement angle at which the output shaft 3 is angularly displaced is adjusted as described later. The gear 4 fixed to the output shaft 3 is meshed with a gear 5b in addition to the gear 5 described above,
The gear 5b meshes with a gear 5a having the same structure as the gear 5. The gear 5b is provided to change the rotation direction of the gear 5a. The configuration of the gear 5a on the lower side of FIG. 3 is the same as the configuration of the above-described first illustration, and is represented by the same reference numeral with reference numeral a.

The gear 5 is fixed to a shaft 6, and is supported together with the shaft 6 by bearings 26 and 27 with respect to the main body 25 so as to be angularly displaceable. The angular displacement member 7 is rotatably supported by the bearing 16 with respect to the shaft 6, and is fixed by the receiving member 29 in the vertical direction in FIG.

As described above, the support member 12 is angularly displaced together with the shaft 6,
It is mounted so as to be displaceable in the vertical direction, and the follower 10 is fixed. A roller 11 is provided above the follower 10, whereby the support member 12 is displaced along the cam surface 9 in the longitudinal direction of the shaft 6. Further, a pin 13 is supported on the opposite side of the support member 12 in the radial direction of the follower 10 and extends downward in FIG. A pressing member 55 is attached to the lower part of the shaft 6.

The pressing member 55 includes a main body 53, a spring 52, and an actuating piece 54, and the main body 53 has two elongated holes 37 and 38. The locking rod 39 provided on the shaft 6 is loosely inserted into the long holes 37 and 38,
Thereby, the main body 53 is locked to the shaft 6. A spring 15 is provided between the main body 53 and the support member 12, whereby the support member 12 is pressed upward in FIG. 3 and the roller 11 is pressed against the cam surface 9.

The spring 52 is mounted between the bottom surface of the shaft 6 and the operating piece 54, and presses the operating piece 54 downward in FIG. The operating piece 54 is locked by the main body 53. This spring 52 is chosen to have a smaller spring constant than the spring 15.

An optical fiber 32 is fixed in the vicinity of the operating piece 54, and the optical fiber 32 is connected to a detector 31 including a light emitting element and a light receiving element. This detector 31 is fixed to the main body 25. Such an optical fiber 32 and the detector 31 constitute an optical sensor, and it is detected that the operating piece 54 is pressed upward from below in FIG. 3 against the spring force of the spring 52 against the main body 53. To do.

FIG. 4 is a side view of the torsion spring mounting machine 1. Elevator
40 is composed of a stopper cylinder 71, stoppers 76, 99, a guide rod 73 which is a piston rod, a lifting cylinder 74, and a support body 75. The guide rod 73 is fixed to the support body 75, while the lifting cylinder 74 is displaced in the vertical direction in FIG. 4 by air pressure or the like. The main body 25 of the torsion spring mounting machine 1 is connected to the lifting cylinder 74. Since the main part of the torsion spring mounting machine 1 is fixed or supported by the main body 25, it is displaced in the vertical direction in FIG. There are two positions at which the downward displacement of the main part of the torsion spring mounting machine 1 in FIG. 4 is stopped. First, in the first stop position, the lifting cylinder 74 is displaced downward while the stopper cylinder 71 is displaced in the direction indicated by the arrow 100, and the stopper 76 and the contact piece 72 fixed to the lifting cylinder 74 are Is the position where abutted. The second stop position is
This is the position where the stopper cylinder 71 is displaced to the arrow 101 from the state of the first stop position, and the lower end portion 74a of the elevating cylinder 74 abuts the tip of the stopper 99. 7 for each
By adjusting 6,99, the first and second stop positions can be adjusted. Whether the first stop position is a normal position of the work 45 described later as shown in FIG. 7 (1) or an abnormal position as shown in FIG. 7 (2) is the first stop position. Position for detecting the
After confirming that the work 45 is in the state shown in FIG. 7 (1), the stop position is further displaced when the torsion spring mounting machine 1 is displaced downward and the torsion spring 41 is mounted on the locking piece 30. The position. At this time, spring the work 45 up.
It is prevented by 15 and the pressing member 55.

FIG. 5 is a plan view of the torsion spring mounting machine 1. As described above, the lever 35 is fixed to the output shaft 3 of the rotary actuator 2, and the lever 35 is moved along with the angular displacement of the output shaft 3 from the position shown by the solid line in FIG. That is, it is angularly displaced by the displacement angle θ. Virtual line 58
The stop position indicated by can be adjusted by operating the stopper 36. The fact that the lever 35 is at the position shown by the solid line in FIG. 5 is detected by the detector 60, and the fact that it is at the stop position shown by the phantom line 58 is at the detector 59.
Is detected by. By detecting the position of the lever 35 in this manner, a series of operations can be reliably performed. For example, if the detector 59 detects that the lever 35 has angularly displaced from the position shown by the solid line in FIG. 5 in the direction shown by the arrow 66 and has reached the position shown by the phantom line 58, as described above. Thus, the piston rod 23 is displaced with respect to the cylinder 24 in the direction indicated by the arrow 34.

This cylinder 24 is fixed to the bracket 51,
51 is fixed to the main body 25. Therefore, when the piston rod 23 is displaced in the direction of the arrow 34 with respect to the main body 25, the angular displacement member 7 and the angular displacement member 7a are thereby displaced by the arrows 78 and 80.
Are angularly displaced in the directions indicated by. Thus, as described above, the pin 13 and the pin 13a are respectively displaced in the axial direction.

Conversely, the lever 81 moves from the position indicated by the phantom line 58 to the arrow 81.
When it is detected by the detector 60 that the piston rod 23 is angularly displaced in the direction indicated by and is angularly displaced until it is indicated by the solid line in FIG. 5, the piston rod 23 is displaced in the direction indicated by the arrow 33. It As a result, the angular displacement member 7 and the angular displacement member 7a are angularly displaced in the directions indicated by arrows 77 and 79, respectively.
Return to the initial position.

FIG. 6 is a sectional view taken along section line VI-VI in FIG. The driving piece 18 is fixed to the piston rod 23,
Displaces with 23 displacements. This drive piece 18 has slots 19 and 2
0 and notches 21 and 22 are formed. A pin 90 is loosely inserted into the long hole 19 and a pin 91 is loosely inserted into the long hole 20, and the drive piece 18 is guided and displaced by the long holes 19 and 20 in accordance with the displacement of the piston rod 23.

Further, projections 28a and 28 provided on the angular displacement members 7a and 7 are loosely inserted into the notches 21 and 22, respectively.
With the displacement of 18, the angular displacement member 7 and the angular displacement member 7a are angularly displaced. For example, when the piston rod 23 is displaced in the direction indicated by the arrow 33, the angular displacement members 7a, 7 are angularly displaced in the directions indicated by the arrows 77, 79, respectively.

On the contrary, when the piston rod 23 is displaced in the direction indicated by the arrow 34, the angular displacement members 7a, 7 are angularly displaced in the direction indicated by the arrows 78, 80.

A circumferential development view of the end piece cam 8 fixed to the angular displacement member 7 is shown in FIG. 10 (1). The cam surface 9 of the end piece cam 8 connects the two surfaces 93 and 95 perpendicular to the axial direction of the shaft 6 and having the step 1 and these two surfaces 93 and 95, and the boundary with the side surface is a spiral line. And a surface 94 forming a part. Since the end piece cam 8 is angularly displaced in the directions indicated by the arrows 79 and 80 in accordance with the angular displacement of the angular displacement member 7, the roller 11 is pressed through the support member 12 via the support member 12 when being pressed against the surface 94. The pin 13 connected to the roller 11 is displaced downward or upward in FIG. 10 (1).

As described above, when the main part of the torsion spring mounting machine 1 is displaced downward in FIG. 4 by the elevator 40, the operating piece 54 of the pressing member 55 is moved to the downward direction in FIG. As shown in, a slight gap is provided with the work 45, or a slight contact is made. The work 45 is a U-shaped metal plate or the like, and a large-diameter insertion hole 47 and a small-diameter insertion hole 46 are formed on the opposing surfaces, respectively. This insertion hole
A shaft 49 penetrates 47, and a small diameter portion of the tip end of the shaft 49 is fitted in the insertion hole 46. A coil-shaped torsion spring 41 is fitted in the large-diameter portion of the shaft 49, and one end 42 of the torsion spring 41 is locked by a locking piece 48 formed on a work 45.
The end 43 of the torsion spring 41 is locked by the pin 13 as described later.

An optical fiber 32 fixed to the main body 25 is provided in the vicinity of the operating piece 54 of the pressing member 55, whereby the positional relationship between the operating piece 54 and the main body 53 is detected. That is, for example, as shown in FIG. 7 (2), the small diameter portion of the tip of the shaft 49 is inserted through
When it is not fitted in 46, the operating piece 54 is pushed upward in FIG. At this time, the first stop position for stopping by the stopper 76 is adjusted so that the work 45 is pressed only by the contraction of the spring 52. When such a state is detected by the optical fiber 32, the torsion spring mounting machine 1 is configured to warn of an abnormal state by, for example, stopping the operation.

FIG. 8 is a diagram for explaining the operation of the gears 4,5, 5a, 5b. The gear 4 connected to the output shaft 3 of the rotary actuator 2 meshes with the gear 5 and the gear 5b. The gear 5b also meshes with the gear 5a. Therefore, for example, when the gear 4 is angularly displaced in the direction indicated by the arrow 66, the gears 5 and 5b are angularly displaced in the directions indicated by the arrows 67 and 68, respectively, and the gear 5a is in the opposite direction to the gear 5, that is, It is angularly displaced in the direction indicated by arrow 69. In this way, in this embodiment, the structure for mounting one torsion spring corresponding to the gear 5 and the structure for mounting another torsion spring corresponding to the gear 5a are individually provided, Two torsion springs can be installed at the same time.

Gears 5 and 5a are supported by shafts 6 and 6a in the direction of angular displacement.
It is fixed to 7,7a respectively, and therefore pins 13,13a
Is angularly displaced along with the angular displacement of the gears 5, 5a.

FIG. 9 is a diagram for explaining the operation of such a torsion spring mounting machine 1. With the elevator 40 described above, the pin 13
Is displaced to the above-mentioned second stop position as indicated by arrow 61 in the lower part of FIG. At this time, the work 45 is a pressing member.
It is pressed and fixed by 55. The positional relationship between the cam surface 9 of the end piece cam 8 and the roller 11 at this time is shown in FIG. 10 (1).

Next, with the angular displacement of the rotary actuator 2, the pin 13
The recess 14 is displaced in the direction indicated by the arrow 62. At this time, the recess 14 locks the end portion 43 of the torsion spring 41 at the position P1, and displaces the end portion 43 in the direction opposite to the direction in which the torsion spring 41 urges the spring. The roller 11 is sequentially moved to the surfaces 93, 94, 95, and has the positional relationship shown in FIG. 10 (2). The end portion 43 of the torsion spring 41 at this time is shown by an imaginary line 96 in FIG.

Thereafter, the piston rod 23 is displaced by the cylinder 24 and the end piece cam 8 is angularly displaced in the direction indicated by the arrow 80, so that the pin 13 together with the roller 11 is indicated by the arrow 63. Then, it is displaced downward in FIG. At this time, the roller 11 is connected near the center of the surface 94, as shown in FIG. 10 (3). The state of the end portion 43 of the torsion spring 41 at this time is shown by an imaginary line 97.

Next, when the rotary actuator 2 is angularly displaced in the opposite direction to that described above, this causes the roller 11 to move from the surface 94 to the surface 93, whereby the recess 14 of the pin 13 is indicated by the arrow 64. Displace in the direction shown. In the middle of this displacement, the end portion 43 is locked by the locking projection 30, and the end portion 43 stops at the position shown by the imaginary line 98 in FIG. Pin 13 separates from torsion spring 41
Return to P1. The state of the roller 11 at this time is shown in FIG. 10 (4). After that, the piston rod 23 is displaced by the cylinder 24 and the end piece cam 8 is angularly displaced in the direction indicated by the arrow 79, and the positional relationship between the roller 11 and the end piece cam 8 is the tenth.
It is returned to the initial state shown in FIG.

After that, the pin 13 is displaced in the direction shown by the arrow 65 in FIG. 9 by the elevator 40, and thus the torsion spring 41 is attached to the chassis where the locking projection 30 and the shaft 49 are fixed together with the work 45. To be done.

As described above, according to this embodiment, the torsion spring can be easily operated.
It becomes possible to attach 41 to chassis. Further, in the present embodiment, since the angular displacement around the shaft 6 and the axial displacement of the pin 13 can be performed at the same time, the stopping point of the pin 13 can be reduced, and thus the device can be reduced. It is possible to simplify the configuration of.

The shape of the tip of the pin 13 may be any other shape as long as it can lock the end portion 43 of the torsion spring 41.

The present invention is not only implemented in connection with a torsion spring mounting machine, but can be widely implemented in other fields.

In the illustrated embodiment described above, the cam 8 is attached to the angular displacement member 7 and the follower 10 is attached to the support member 12. However, as another embodiment of the present invention, the cam 8 is supported. The structure may be such that it is attached to the member 12 and the follower 10 is attached to the angular displacement member 7.

Advantageous Effect of the Invention According to the present invention, the shaft 6 is angularly driven by the rotary actuator means 2-5, whereby the support member 12 is angularly displaced together with the shaft 6 and is provided on the support member 12. The cam 13 is caused by angularly displacing the working member 13 such as a locking pin for locking the end 43 of the torsion spring 14 to be driven and rotationally driven around the shaft 6 by the cylinder means 18 to 24, 28. The means drive the support member 12 and thus the working member 13 in the axial direction of the shaft 6, thus driving the working member 13 in the axial direction of the shaft 6 and making a complex angular displacement about the shaft 6. It is possible to realize various operations with a simple configuration.

[Brief description of drawings]

FIG. 1 is a perspective view showing a part of the structure of a torsion spring mounting machine 1 provided with a cam mechanism of one embodiment of the present invention, and FIG. 2 is a view for explaining the operation of a pin 13 of the torsion spring mounting machine 1. Figure,
3 is a sectional view showing the structure of the main part of the torsion spring mounting machine 1, FIG. 4 is a side view of the torsion spring mounting machine 1, FIG. 5 is a plan view of the torsion spring mounting machine 1, and FIG. Cut plane line of Fig. 3
VI-VI sectional view, FIG. 7 is a view for explaining a state in which the pressing portion 55 is pressing the work 45, FIG. 8 is a gear 4,
5, 5a, 5b are views for explaining the angular displacement mode, FIG. 9 is a perspective view for explaining the operation of the pin 13, and FIG. 10 is a roller 11
End cam 8 for explaining the positional relationship between the end cam 8 and the end cam 8.
FIG. 1 ... torsion spring mounting machine, 2 ... rotary reactor, 3 ... output shaft, 4,5 ... gear, 6 ... shaft, 7 ... angular displacement member, 8 ... end cam, 9 ... … Cam surface, 10 …… Hollower, 11 …… Roller, 12 …… Supporting member, 13 …… Pin, 14…
… Concave, 18 …… Drive piece, 23 …… Piston rod, 24 …… Cylinder, 25 …… Main body, 26,27 …… Bearing, 28 …… Protrusion, 30
...... Locking piece, 40 ...... Elevator, 41 ...... Torsion spring, 42,43
...... End, 45 …… Workpiece, 46,47 …… Insertion hole, 48 …… Locking piece, 49 …… Shaft, 55 …… Pressing member

Claims (1)

[Scope of utility model registration request] 1. A shaft 6, a main body 25 for rotatably supporting the shaft 6, a rotary reactor means 2-5 provided on the main body 25 for driving the shaft 6 in an angular displacement, and a shaft 6 inserted therethrough, A support member 12 that is displaceable in the axial direction of the shaft 6 and is angularly displaced together with the shaft 6 in the rotation direction of the shaft 6.
A working member 13 provided on the support member 12 and extending to one end side of the shaft 6 for performing work; and a spring for applying a spring force to the support member 12 on the other end side of the shaft 6.
15, the shaft 6 is inserted, and the shaft 6 is inserted in the axial direction of the shaft 6 rather than the support member 12.
An angular displacement member 7 rotatably provided around the shaft 6 on the other end side of the shaft 6 and a cam means, the cam means facing the axial direction of the shaft 6 and having an axial position in the circumferential direction. Changing cam surface 9
And a follower 10 opposed to the cam surface 9, which is interposed between the angular displacement member 7 and the support member 12. The spring 15 presses the cam surface 9 and the follower 10 together. , Either one (8 or 10) is attached to the angular displacement member 7,
One of the other (10 or 8) is attached to the support member 12, and the main body 25 is provided with one end and the other end is connected to the angular displacement member 7 to expand and contract to angularly displace the angular displacement member 7. A cam mechanism including cylinder means 18-24, 28 that are driven to change the relative positions of the angular displacement member 7 and the support member 12.