JPH07166708A - Torque limiter - Google Patents

Abstract

PURPOSE:To position and stop an output member which moves in accordance with load at a predetermined position securely without causing excessive load concerning a torque limiter. CONSTITUTION:A rotation limit means 319 which limits relative rotation angle of an input member 311 and an output member 313 of a torque limiter main body 311 in which the output member 313 is connected and interlocked with a positioning mechanism 33 to a fixed angle or less is provided, and a means which stops drive of the input member 311 when a claw 334 is caught into a groove 332 of a rotary plate 331 of the positioning mechanism 33. When torque transmission is shut off at a position where the groove 332 is not opposed to the claw 334, the rotary plate 331 is positioned at a predetermined position by rotating the input member 311 for more than a fixed period of time and drive of the input member 313 is stopped to prevent occurrence of excessive load.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a torque limiter, and more particularly to a torque limiter which can reliably position and stop an output member interlocking with a load at a predetermined position.

[0002]

2. Description of the Related Art Generally, a torque limiter is shown in FIG.
, An input member 131a for inputting a driving force,
The output shaft 131h is configured to rotate coaxially with the input member 131a when the load torque received by the output shaft 131h exceeds a certain value.

In this conventional example, the input member 13 is used.
A chrysanthemum seat surface 131b is formed on the end surface of 1a, and the output shaft 131
A ball 131d held by a ball holding plate 131c formed integrally with h is pressed against the chrysanthemum seat surface 131b by a spring 131f.

As shown in FIG. 1B, the chrysanthemum seat surface 131b.
When the ball 131d is pushed into the trough, the chrysanthemum seat surface 131d drives the ball 131d in the rotation direction of the input member 131a, and the ball holding plate 131c holding the ball 131d and the output shaft 131h move the input member 131a. Torque is transmitted.

When a load is applied to the output shaft 131h, the ball 131d is driven by the load in a direction opposite to the rotation direction of the input member 131a and moves toward the ridge of the chrysanthemum seat surface 131b. The spring 131 moves the ball 131d to the ridge.
Although suppressed by the pressure of 1f, when the ball 131d moves to the ridge of the chrysanthemum seating surface 131b due to the load as shown in FIG.
Transmission of torque to h is blocked, and overload is prevented.

After the torque transmission is cut off, the input member 131
Whether or not to continue driving a is free, but driving of the input member 131a is often stopped so as not to waste energy.

In the above structure, when the output shaft 131h is required to stop at a predetermined rotational position, a positioning mechanism 133 as shown in FIG. 19 is provided. This positioning mechanism has a positioning groove 133b at one position on the peripheral edge thereof, and is connected to the input member 131a in an interlocking manner with the rotary plate 133a.
And a claw 133c pressed by a spring 133d is provided on the peripheral surface of the rotary plate 133a.
3b to position the stop position of the output shaft 131h, and to release the positioning action by pulling the claw 133b against the spring 133d from the groove 133b by an actuator (not shown) against the spring 133d at the time of startup. I have to.

The positioning mechanism 133 releases its positioning action when the claw 133c is first pulled out of the groove 133b against the spring 133d. Then output shaft 131h
When the torque limiter is activated (or before the torque limiter is activated, the actuator is deactivated), and the spring 133d causes the claw 133 to move.
c is pressed against the peripheral surface of the rotary plate 133a. After that, the output shaft 131h rotates, the claw 133c is fitted into the groove 133b, the output shaft 131h is positioned and stopped.

As a result, the load torque applied to the torque limiter via the rotary plate 133a becomes a predetermined value or more,
The torque limiter interrupts the transmission of torque and prevents the motor from being overloaded. And nail 13
When it is detected that the roller has stopped at a predetermined position due to the position of 3c, the rotation phase of the rotary plate 133a, etc., the motor is stopped.

It is also possible to activate the positioning means after the torque limiter is activated. That is, after the torque limiter operates, the rotary plate 13 that rotates by inertia
The claw 133c is engaged with the groove of 3h.

[0011]

According to the above-mentioned conventional structure, as shown in FIG. 17 (a), when the ball 131d pushed into the valley of the chrysanthemum seat surface 131b gets over the ridge of the chrysanthemum seat surface 131b, input is made. The torque applied to the member 131a gradually increases. When the torque applied to the output shaft 131h is larger than the torque shown in FIG. 17A, the torque limiter operates, so there is no problem. However, as described later, the output of the output shaft 131h is used for twisting the wire rod. In such a case, as shown in FIG. 17B, the load torque applied to the output shaft 131h gradually increases according to the twist amount of the wire. In this case, the operating position of the torque limiter (operating rotational position: BC in FIG. 17A) becomes unstable, and the torque limiter often does not operate at the expected position.

Further, in the above-mentioned conventional positioning mechanism, the claw 133 is forcibly inserted into the groove 133b before the torque limiter operates.
When the torque limiter is actuated by engaging a, the output shaft 131h stops according to the intention of the operator regardless of the torque on the load side.

However, as will be described later, when the twisting torque of the wire needs to be a predetermined value or more, as in the case where the torque limiter is used for twisting the wire, the operator arbitrarily outputs the torque as described above. The above configuration of stopping the shaft 131h does not help.

Further, in the configuration in which the output shaft which rotates by inertia after the operation of the torque limiter is positioned, the output shaft 13 described above is used.
In order to secure the inertia of 1 h, a flywheel or the like is required, which is a large size.

The present invention has been proposed in view of the above-mentioned conventional circumstances, and the torque limiter operates accurately according to the torque of the load, and the rotation positioning mechanism of the output shaft when stopped is simple and accurate. An object of the present invention is to provide a torque limiter having various configurations.

[0016]

To achieve the above object, the present invention employs the following means. That is, as shown in FIG. 1, an input member (311) for inputting a driving force,
A torque limiter that includes an output member that rotates in conjunction with the input member and receives a load, and that cuts off the transmission torque between the input member (311) and the output member when the load torque exceeds a predetermined value. Limiter body (31)
The input member (311) has a ball pressing mechanism that presses the ball (313a) with a spring (333) against a circular hole (311c) having a diameter smaller than the diameter of the ball (314). .

An input member (311) for inputting a driving force
And a torque limiter body that cuts off the transmission torque between the input member (311) and the output member when the load torque exceeds a predetermined value while rotating in conjunction with the input member and receiving a load. In a torque limiter equipped with (31), a rotation limiting means (319) for limiting the relative rotation angle between the input member (311) and the output member after the torque limiter body (31) is activated to a certain angle or less. The torque limiter body (31) is provided with a positioning mechanism (33) for positioning the output member that rotates with an angle delay defined by the rotation limiting means (319) after the operation.

The rotation limiting means (319) is provided with an input member (31
1) The rotation limit pin (319a) standing upright and the output member rotate together to hold the ball (314) on the input member, and each rotation limit pin (319a) moves in the circumferential direction by a certain angle or less. The ball holding plate (312) is provided with a plurality of circular arc holes (319b) that can be inserted.

The positioning mechanism (33) is interlockingly connected to the output member of the torque limiter body (31) and has a rotating plate (331) having a positioning groove (332) formed on its peripheral surface, and the rotating plate (331). It is pressed against the peripheral surface of (331) by the spring (333),
The claw (334) that bites into the groove (332) is provided.

The positioning mechanism is provided with a positioning releasing means for separating the claw (334) bitten in the groove (332) from the groove (332) against the spring (333). Further, the torque limiter is an input member when the positioning mechanism (33) operates.
The drive stop means for stopping the drive of (311) is provided.

[0021]

According to the above ball pressing mechanism, the input member (31
Since the transmission torque of 1) sharply decreases with respect to the moving distance of the ball 314, the operating position becomes stable.

According to the rotation limiting means 319,
After the torque limiter is actuated, the relative rotation angle between the input member 311 and the output member 313b is limited to a certain angle or less. Therefore, when the torque limiting action of the torque limiter 31 is started, the output member 313b is temporarily rotated. However, when the input member 311 rotates with respect to the output member 313b by a certain angle or more, the input member 311 and the output member 3 are rotated.
The relative rotation with respect to 13b is restricted, and the output member 313b rotates again with the input member 311.
The rotary plate 331 of the positioning mechanism 33 that is interlocked with b is driven to a rotational phase in which the groove 332 formed on the peripheral surface and the claw 334 face each other.

Then, when the groove 332 and the claw 334 face each other, the claw 334 of the positioning mechanism 33 is pushed into the groove 332 by the spring 333, and the output member 313b is reliably stopped at a predetermined rotation phase. Moreover, since the driving of the input member 311 is stopped at the same time as this positioning, the occurrence of overload due to positioning is prevented.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A case where a twisted wire binding machine using a torque limiter according to an embodiment of the present invention is applied will be specifically described below with reference to the drawings.

As shown in FIG. 2, a twisted wire binding machine to which an embodiment of the present invention is applied is a bit 1 that rotates by engaging a twisted wire W, a motor 2, and a bit 1 for the motor 2. And a transmission mechanism 3 for interlocking the. The transmission mechanism 3 includes a torque limiter body 31, a one-way clutch 32, and a positioning mechanism 33 for restricting a stop position of the bit 1, that is, a rotation phase at the time of stop. An operation mechanism 4 for releasing the function is provided.

As shown in FIG. 3, the torque limiter main body 31 includes a rotary plate 311 as an input member that is interlockingly connected to the motor 2 via a first reduction gear mechanism 34. A central hole 311a is formed in the rotary plate 311, and the rotary plate 311 is provided on one surface opposite to the motor 2 at a predetermined distance from the rotation axis and at equal intervals in the circumferential direction.
Individual ball receiving holes 311b are formed.

Further, the torque limiter main body 31 has a ball holding plate 312 which is arranged so as to be coaxially rotatable so as to face the one surface of the rotary plate 311, and the ball holding plate 31.
Two ball holding holes 312a are formed in 2 at a predetermined distance from the axis of rotation corresponding to the ball receiving holes 311b and at equal intervals in the circumferential direction. Further, an output shaft 313 as an output member, which penetrates the shaft center of the ball holding plate 312 or is formed integrally with the ball holding plate 312, is fixed, and the output shaft 313 extends from the ball holding plate 312 to the rotary plate 311. A ball holding plate 312 and a long shaft portion 313b projecting from the ball holding plate 312 to the opposite side of the rotary plate 311. The short shaft portion 312a has the short shaft portion 313a.
It is rotatably fitted in the center hole 311a of the frame 11 and is rotatably supported by the inner end plate frame 36a of the frame 36 via a bush 39.

Further, three balls 314 are inserted into each ball holding hole 312a so as to be free to move in the direction of the rotation axis of the ball holding plate 312, and these balls 314 of the ball holding plate 312 correspond to the rotation plate 311 of the rotation plate 311. On the opposite side, the long shaft portion 313
In b, it is possible to move back and forth in the direction of the rotation axis of the ball holding plate 312,
The spring 316 presses the rotating plate 311 via the pressing plate 315 rotatably fitted around the rotation axis of the ball holding plate 312.

As shown in FIG. 4, the ball receiving hole 311b formed in the rotary plate 311 is a circular hole 311c having a diameter smaller than that of the ball 314, and the rotary plate 31 is continuous with the circular hole 311c.
It is formed with a countersink 311d that has a diameter increased as it approaches the surface of No. 1 and has a diameter larger than that of the ball 314 on the surface of the rotary plate 311. This maximizes the transmitted torque when the ball 314 begins to move, as shown in FIG.
The twisting torque of the twisted wire is determined only by the transmission torque when the movement of the ball 314 is started. The transmission torque when the ball 314 moves is as shown in FIG.
It is determined by the ratio between the diameter of 14 and the diameter of the circular hole 311c, and the pressure of the spring 316.

For example, if the pressure of the spring 316 is the same, the larger the ball diameter compared to the diameter of the circular hole 311c, the greater the initial transmission torque, and then the abrupt decrease. Further, as a matter of course, the larger the pressure of the spring 316, the larger the transmission torque. By design, circular hole 311c
It is advantageous to adopt a configuration in which the initial transmission torque is adjusted by adjusting the spring pressure to about half the diameter of the ball 314 or less and adjusting the spring pressure. Also, countersink 311d
Is essentially unnecessary, but in the present embodiment, a stroke for operating the lever 45 described later is provided with a countersink 311d.
It is secured by the taper.

Here, as shown in FIG. 3, the pressing plate 315 has a disk-shaped plate body 315a having a round hole at the center.
A cylindrical portion 315b for smoothing the forward and backward movement of the plate body 315a in the direction of the rotation axis of the ball holding plate 312. The spring 316 has a spring seat 318, which is prevented from coming out of the long shaft portion 313b by a pin 317 inserted into the tip of the long shaft portion 313b, and the pressing plate 315.
Between the main body 315a and the main body 315a. A small gear 35a of a second reduction gear mechanism 35, which will be described later, is integrally formed with the spring seat 318.

The torque limiter body 31 has a rotation limiting means 319 for limiting the relative rotation of the rotary plate 311 and the ball holding plate 312 to a certain angle or less.
Is provided. The rotation limiting means 319 is provided on the rotating plate 31.
The three limiting pins 319a protruding from the ball holding plate 312 side toward the ball holding plate 312, and the three rotation limiting pins 319a formed on the ball holding plate 312 are inserted so as to be movable within a predetermined angle in the circumferential direction. The circular arc hole 319b is provided, and the rotating plate 31 is provided by the torque limiting action of the torque limiter body 31.
After the torque transmission from 1 to the ball holding plate 312 is cut off, the rotation plate 311 is rotated by a predetermined angle or more by the motor 2 so that the ball holding plate 312 can be rotated in association with the rotation of the rotation plate 311. .

As shown in FIG. 2, the second reduction gear mechanism 35 interposed between the torque limiter body 31 and the one-way clutch 32 is rotatably supported by the small gear 35a and the intermediate plate frame 36b. The intermediate large gear 35b meshes with the small gear 35a, the intermediate small gear 35c fixed to the intermediate large gear 35b, and the final large gear 35d meshed with the intermediate small gear 35c.

As shown in FIGS. 6 and 7, the one-way clutch 32 is the final large gear 3 of the reduction gear mechanism 35.
An outer peripheral ring 321 formed integrally with the 5d, and a hexagonal shaft 32 coaxially rotatably inserted inside the outer peripheral ring 321.
2, and a pair of roller holding plates 323 are fixed to the hexagonal shaft 322 at appropriate intervals in the axial direction, and both ends of three roller shafts 324 are fixed to both roller holding plates 323. Arc-shaped holes 325 that are fitted so as to be movable in parallel in the circumferential direction are formed at equal intervals in the circumferential direction. Also, each roller shaft 3
The outer ring 3 is provided between the roller holding plates 323.
A clutch roller 326 having a diameter smaller than the maximum distance between the shaft 21 and the hexagonal shaft 322 and larger than the minimum distance is rotatably fitted onto the clutch roller 326. A round hole 328 into which both ends of the spring support shaft 327 is fitted is formed between the arcuate holes 325 of each roller holding plate 323, and a spiral spring held by both roller holding plates 323 via the spring support shaft 327. By 329, each clutch roller 325 is individually pressed against the outer peripheral surface of the hexagonal shaft 322.

The positioning mechanism 33 includes a rotary plate 331 coaxially rotatable with respect to the hexagonal shaft 322 of the one-way clutch 32 within a predetermined range.
31 is integrally formed with each roller shaft 324 of the one-way clutch 32, as shown in FIG. 6, FIG. 7 or FIG.
A positioning groove 332 is formed at one location on the outer peripheral surface.

The positioning mechanism 33 is swingably supported by the connecting shaft frame 36e of the frame 36 shown in FIG.
A claw 334 that is pressed against the outer peripheral surface of the rotating plate 331 by a spring 333 is provided. As shown in FIG. 6, the outer peripheral ring 321 and the hexagonal shaft 322 of the one-way clutch 32.
A central shaft 371 of the chuck device 37 is passed through the rotary plate 331 of the positioning mechanism 33.
71 is rotatably fitted in the outer peripheral ring 321 and fixed to the hexagonal shaft 332 by a pin 378. Further, one end portion 371a of the central shaft 371 is rotatably fitted into the intermediate plate frame 36b of the frame 36 of the transmission mechanism 3, and the central portion is fitted to the tip plate frame 36c of the frame 36 of the transmission mechanism 3 via the bush 38. It is rotatably supported.

A hexagonal hole 372 is formed in the other end 371c of the central shaft 371, and as shown in FIG.
A hexagonal shaft 11 corresponding to the hexagonal hole 372 is formed at the base end of the. Therefore, the hexagonal shaft 11 is attached to the hexagonal hole 37
When inserting into 2, set the mounting angle around the axis of bit 1 to 6
It can be switched every 0 °. Further, as shown in FIG. 6 or 7, the other end portion 371c of the central shaft 371 is
A ball holding hole 373 communicating with the hexagonal hole 372 is formed in the hole, and as shown in FIG. 8, the ball holding hole 37 of the bit 1 is formed.
A peripheral groove 12 is formed in a portion corresponding to 3, that is, in an intermediate portion of the hexagonal shaft 11. Further, as shown in FIG. 6, a positioning ball 374 is movably inserted into the ball holding hole 373, while a sleeve 375 is slidably fitted onto the central shaft 371.

When the sleeve 375 is moved to the chuck position on the side of the other end 371c of the central shaft 371, the ball holding hole 373 is covered with the sleeve 375 so that the ball 374 is pressed by the sleeve 375.
Hexagonal shaft 11 with a part of 74 inserted in hexagonal hole 372
The sleeve 375 into the central groove 371.
The sleeve 375 opens the ball holding hole 374 when moved to the uncuck position on the one end 371a side so that the ball 374 can freely retract into the ball holding hole 373.

A cap 376 is externally fitted and fixed to the other end 371c of the central shaft 371, and the other end of the sleeve 375 is received by the cap 376 so that the sleeve 375 is located at the other end of the central shaft 371 rather than at the chuck position. The movement toward the portion 371c is restricted, and the sleeve 375 is biased to the chuck position by the spring 377 arranged so as to surround the central shaft 371 between the bush 38 and the sleeve 375. .

As shown in FIGS. 2 and 10, the operating mechanism 4 includes an operating lever 42 and a floating lever 43 that are swingably provided around a fulcrum pin 41 fixed to the frame 36.

The operating lever 42 is an operating arm 421 extending from the fulcrum pin 41 to the outside of one end of the motor 2.
And the torque limiter body 31 from the fulcrum pin 41 to the other end side.
And an action arm 422 extended to the vicinity of the operation arm 422, and is attached in the operation release direction (direction in which the operation arm 422 separates from the motor 2) by a spring 44 mounted between the intermediate portion of the operation arm 421 and the frame 36. Energized. A pin lever 45 swingably driven by the main body 315a of the pressing plate 315 of the torque limiter main body 31 is pivotally attached to the tip of the action arm 422, and the free end portion of the pin lever 45 projects toward the floating lever 43 side. Pin 46 is continuously provided, and the free end of this pin lever 45 is the pin lever 4
5 is pressed against the main body 315a of the pressing plate 315 by a spring 47 that is mounted over the control lever 42 and the operation lever 42.

The floating lever 43 includes a switch operating arm 431 extending from the fulcrum pin 41 to the outside of one end of the motor 2 and an operating arm 432 extending from the fulcrum pin 41 to the positioning mechanism 33. The tip of the arm 432 is projected into an engagement hole 335 formed in the claw 334 of the positioning mechanism 33. A pin receiving portion 48 for engaging and disengaging the pin 46 of the pin lever 45 is attached to the action arm 432 of the floating lever 43.
Is provided.

As shown in FIG. 11A, with the pin 46 engaged with the pin receiving portion 48, the operating lever 42 is
Is operated in the operation direction (direction in which the operation arm 421 approaches the motor 2), the floating lever 43 operates the motor 2 in cooperation with the operation lever 42.
(See FIG. 2) is turned on, and the claw 334 of the positioning mechanism 33 is disengaged from the groove 332 against the spring 333.
The driving force of the motor 2 is transmitted to the bit 1 via the transmission mechanism 3, whereby the twisted wires W are twisted together. After that, when the twisting of the twisted wire W progresses and the twisted wire twisting torque acting on the torque limiter body 31 from the bit 1 exceeds the torque limit value, the pressing plate 315 of the torque limiter body 31 drives the pin lever 45, As shown in FIG. 11B, the pin 46 of the pin lever 45 separates from the pin receiving portion 48 of the floating lever 43. And
The claw 334 is elastically pressed against the outer peripheral surface of the rotary plate 331 by the spring 333 of the positioning mechanism 33, and the floating lever 43 interlocked with the claw 334 turns off the switch that operates the motor 2 when the claw 334 fits in the groove 332. To do.

At a position where the claw 334 does not fit into the groove 332, the pin 46 of the pin lever 45 is moved to the floating lever 4
When the pin 43 is separated from the pin receiving part 48, the floating lever 43 interlocked with the claw 334 is located at the same position as when the pin 46 is separated from the pin receiving part 48, and the switch for operating the motor 2 is not turned off. Therefore, the rotation of the motor 2 continues even after the torque limit by the torque limiter body 31 is started, and the rotary plate 331 of the torque limiter body 31 continues to rotate with respect to the ball holding plate 312 stopped by the twisting twisting torque. . When the rotation of the rotary plate 331 with respect to the ball holding plate 312 exceeds a certain angle, the rotation limiting means 319 acts to rotate the rotary plate 33.
1 drives the ball holding plate 312, and the rotary plate 331 of the positioning mechanism 33 rotates. When the groove 332 of the rotary plate 331 rotates to a position facing the claw 334, the claw 334 fits in the groove 332, and the floating lever 42 interlocks with the claw 332 to turn off the switch for operating the motor 2. , The rotation of the motor 2 is stopped.

After that, when the operation lever 42 is released, the operation lever 42 is driven in the operation releasing direction by the spring 44, and the pin 46 of the pin lever 45 returns to the position where it is engaged with the pin receiving portion 48 of the floating lever 43. To do.

Further, as shown in FIG.
Is a frame 36 that extends to the outside of one end of the motor 2.
A main body package 51 fixed to the base portion 36d and an operation lever 52 led out from the main body package.

The operating lever 52 of the switch 5 is pushed by the switch operating lever 431 of the floating lever 43 by the operating lever 42 by operating the operating lever 42 of the operating mechanism 4 in the operating direction as described above, and the switch 5 is turned on. When the pawl 334 of the positioning mechanism 33 is turned on and fitted into the groove 332 after the motor 2 is started, the switch operating lever 431 of the floating lever 43 is released to turn off the switch 5.

A hook-like portion 13 is formed at the tip of the bit 1 as shown in FIG. The hook-shaped portion 13 has an inclined portion 13a that inclines to one side from a position spaced a predetermined distance from the tip, a curved portion 13b that is bent to the axis of the bit 1 continuously from the inclined portion 13a, A sloped portion 13a extending from the shaft center 14 in the opposite direction, and a hook tip portion 13c that gently bends toward the base end direction of the bit 1;
Is smoothly connected to the tip side curved surface 13e of the hook tip portion 13c, and is 10 to the axis perpendicular to the axis 14 of the bit 1.
It is inclined by 20 ° (here, about 15 °).

As shown in FIG. 12, the frame 36,
The motor 2, the transmission mechanism 3, and the operation mechanism 4 are composed of the operation lever 41 of the operation mechanism 4, one end of the frame 36, and the transmission mechanism 3.
The main body case 6 is housed in the main body case 6 except for the cap 376 and the sleeve 375, and the base end portion of the operation lever 41 of the operation mechanism 4 and one end portion of the frame 36 are provided with the main body case 6 together with the switch 5, a dry battery as a power source and wiring. Is housed in a grip case 7 that is connected to one end side of the.

Holding the grip case 7 with one hand, as shown in FIG. 13, (a) insert the hook-shaped portion 13 of the bit 1 into the folded portion of the stranded wire W folded back in a U-shape, and further (b).
Hook the end portion of the twisted wire W with the other hand to the double wire of the twisted wire W, hook the hooked portion 13 of the bit 1, and twist the twisted wire binding machine once by hand to twist. Line W has a hook 1 with bit 1
Entangled in 3.

As described above, in this twisted wire binding machine, when the bit 1 is positioned at the position where the claw 334 fits into the groove 332 formed on the peripheral surface of the rotary plate 331 of the positioning mechanism 33, the bit 1 is moved to the previous position. Since the twisted wire binding work is completed, there is no risk of the bit 1 spinning idle when the twisted wire binding machine is screwed by hand to entangle the twisted wire W as described above, and the twisted wire binding machine is screwed once by hand. The twisted wire W can be surely entangled with the bit 1 only by turning, and the workability is improved.

In this way, the twisted wire W is connected to the hook-shaped portion 13 of the bit 1.
Then, when the operation arm 421 of the operation lever 42 of the operation mechanism 4 is squeezed together with the grip case 7, the positioning mechanism 33 releases the positioning action and the motor 2 rotates, as shown in FIG. The bit 1 rotates and the twisted wires W are twisted together. When the twisted wire twist torque increases above a certain level, the bit 1 is positioned in a predetermined rotation phase by the torque limiter body 31 and the positioning mechanism 33, and the floating lever 43 is driven by the spring 333 of the positioning mechanism 33 via the claw 334. Then, the switch 5 is turned off, and the motor 2 is stopped. Further, thereafter, (b) by moving the bit 1 in the opposite direction to the inserted direction, the hook-shaped portion 13 is easily pulled out from the twisted wire W.

In the above embodiment of the positioning mechanism, the ball receiving hole 311b of the torque limiter body 31 is replaced by the round hole 311.
c and a countersunk hole 311d, instead of this, a simple conical ball receiving hole 311b is formed as shown in FIG. 14, or the ball receiving hole 311b is replaced with a conventional one. The chrysanthemum seat surface may be formed.
In this case, the relationship between the transmission torque and the amount of movement of the ball 314 in the axial direction of the rotary plate 311 is proportional to the amount of movement of the ball 314, as shown in FIG. The torque increases, and the twisting torque of the twisted wire is determined depending on the transmission torque at the ratchet opening point where the ball 314 rides on the surface of the rotating plate 311.

However, when the ball receiving hole 311b is formed in a simple conical shape, the processing dimensions of the ball receiving hole 311b are likely to vary, and therefore the twisting torque of the twisted wire is likely to vary. Therefore, in the present invention, the ball receiving hole 311b is smaller than the ball 314 in the round hole 311 in order to reduce the variation in the twisting torque of the twisted wire to an extent that can be almost ignored.
It is recommended to be constituted by c and a countersink 311d which is continuous with this and has a diameter increased toward the surface of the rotary plate 311 and which has a diameter larger than that of the ball 314 on the surface of the rotary plate 331.

Finally, the present invention is widely applied not only to the torque limiter of the twisted wire binding machine, but also to the torque limiter when stable operation and a constant stop position are required.

[0056]

As described above, since the torque limiter of the present invention presses the ball against the circular hole,
When the torque limiter operates, the transmission torque sharply decreases with respect to the movement of the ball, resulting in stable operation.

Further, since the rotation limiting means for limiting the relative rotation of the input member and the output member of the torque limiter main body to a certain angle or less is provided, the rotation of the positioning mechanism stopped due to the torque limiting action outside the predetermined rotation phase. By continuing the rotation of the motor after starting the torque limitation of the plate, the rotating plate can be surely rotated to a predetermined rotation phase, and the claw can be engaged with the groove for positioning.

Since a means for stopping the driving of the input member when the claw is caught in the groove is provided, the driving of the input member is stopped at the same time as this positioning.
It is possible to prevent the occurrence of overload due to positioning.

[Brief description of drawings]

FIG. 1 is a perspective view showing a configuration of the present invention.

FIG. 2 is a side view of a main part of a twisted wire binding machine to which an embodiment of the present invention is applied.

FIG. 3 is an explanatory view of a torque limiter main body of an embodiment of the present invention, including (a) an exploded perspective view, (b) a sectional view when transmitting torque, and (c) a sectional view when shutting off the torque.

FIG. 4 is a sectional view of a ball receiving hole according to an embodiment of the present invention.

FIG. 5 is a characteristic diagram of an example of the present invention, showing (a) transmission torque characteristics and (b) twisted wire twisting torque characteristics.

FIG. 6 is a half sectional view of a one-way clutch and a positioning mechanism according to an embodiment of the present invention.

7A and 7B are explanatory views of a one-way clutch and a positioning mechanism according to an embodiment of the present invention, FIG. 7A is an exploded perspective view, and FIG.
It includes a front view of the one-way clutch during transmission, and (c) a front view of the one-way clutch when disengaged.

8A and 8B are explanatory views of the positioning mechanism according to the embodiment of the present invention, and FIG. 8A is a front view when positioning and FIG. 8B is a front view when positioning is released.

FIG. 9 is a side view of a bit of a twisted wire binding machine to which an embodiment of the present invention is applied.

FIG. 10 is an explanatory view of the operating mechanism of the embodiment of the present invention, including (a) a transverse bottom view and (b) an exploded perspective view.

FIG. 11 is an explanatory view of a pin lever of one embodiment of the present invention, including (a) a side view when the pin is engaged and (b) a side view when the pin is disengaged.

FIG. 12 is a perspective view of the appearance of a twisted wire binding machine to which an embodiment of the present invention is applied.

FIG. 13 is an explanatory diagram of a twisted wire entanglement work.

FIG. 14 is an explanatory diagram of a twisting operation of twisted wires.

FIG. 15 is a graph showing the relationship between transmission torque and ball movement distance.

FIG. 16 is a sectional view of a ball receiving hole according to another embodiment of the present invention.

FIG. 17 is a characteristic diagram of another example of the present invention, (a)
The transmission torque characteristic and (b) twisted wire torsion torque characteristic are shown.

FIG. 18 is an explanatory diagram of a conventional torque limiter,
Including (a) exploded perspective view, (b) sectional view at the time of torque transmission, and (c) sectional view at the time of torque interruption.

FIG. 19 is an explanatory view of a conventional positioning mechanism, (a)
The front view at the time of positioning and the front view at the time of (b) positioning cancellation are included.

[Explanation of symbols]

 16 Spring 31 Torque Limiter Main Body 33 Positioning Mechanism 311 Input Member 314 Ball 331 Rotating Plate 332 Groove 333 Spring 334 Claw

Claims (6)

[Claims] 1. An input member (311) for inputting a driving force, and an output member that rotates in conjunction with the input member and receives a load, and the input member (311) when the load torque exceeds a predetermined value. In the torque limiter that includes the torque limiter body (31) that blocks the transmission torque between the output member and the output member, the diameter of the ball (314) formed on the end surface of the input member (311) of the torque limiter body (31) A torque limiter comprising a ball pressing mechanism for pressing a ball (313a) by a spring (333) against a circular hole (311c) having a small diameter. 2. An input member (311) for inputting a driving force, and an output member that rotates in conjunction with the input member and receives a load, and the input member (311) when the load torque exceeds a predetermined value. In a torque limiter having a torque limiter body (31) for shutting off the transmission torque between the output member and the output member, relative rotation between the input member (311) and the output member after the torque limiter body (31) is activated. Rotation limiting means (319) for limiting the angle to a certain angle or less, detecting means for detecting the operation of the torque limiter body (31) and transmitting it to the output member, and operation of the torque limiter body detected by the detecting means. A torque limiter comprising a positioning mechanism (33) for positioning the output means in response to the result. 3. The rotation limiting means (319) rotates interlockingly with a rotation limiting pin (319a) provided upright on the input member (311) and an output member, and holds a ball (314) on the input member. The torque limiter according to claim 2, further comprising a ball holding plate (312) provided with an arc hole (319b) through which each rotation limiting pin (319a) is inserted so as to be movable in a circumferential direction by a predetermined angle or less. 4. A rotating plate (331) in which the positioning mechanism (33) is interlockingly connected to the output member of the torque limiter body (31) and has a positioning groove (332) formed on its peripheral surface. The torque limiter according to claim 2, further comprising: a claw (334) which is pressed by a spring (333) on the peripheral surface of the rotary plate (331) and is engaged with the groove (332). 5. A torque limiter having a positioning releasing means for separating a claw (334) bitten in the groove (332) from the groove (332) against a spring (333). 6. The torque limiter according to claim 2, further comprising drive stopping means for stopping the driving of the input member (311) when the positioning mechanism (33) operates. .