JPH087148Y2 - Electromagnetic spring clutch - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a rotary shaft and a rotary body, which are arranged on the same axis by a coil spring being fastened to a flange of the rotary shaft and a boss of the rotary body. The present invention relates to an electromagnetic spring clutch that rotates integrally.

[Conventional technology]

Conventionally, an electromagnetic spring clutch of this type is disclosed in, for example, Japanese Utility Model Laid-Open No. 57-65235. This electromagnetic spring clutch is composed of a cylindrical non-magnetic metal material and has a rotary shaft having a flange at a substantially central portion in the axial direction, and a rotary shaft that is rotatably fitted on the rotary shaft and is adjacent to, for example, the right side of the flange. A rotary body having a boss of the same diameter is provided, and a coil spring having one end fixed to the right end of the boss is provided on the outer peripheral surface of the flange and the boss having substantially the same diameter from the fixed end. It is fitted over almost the entire length extending to the left end of the flange. A cylindrical boss of an armature having a disk portion is fitted to the coil spring so as to be movable back and forth in the axial direction, and the groove formed at the left end of the boss has a groove other than that of the coil spring. The edge is locked.

On the other hand, the rotor formed in an annular shape is adjacent to the flange of the rotary shaft and is integrally fitted on the rotary shaft,
Further, a coil bobbin around which an electromagnetic coil is wound is provided radially outward of the rotor and the boss of the armature.
The field core is arranged so as to be held by a field core that is fixed to the equipment fixing portion side, and the inner peripheral surface of the disc-shaped bottom of the field core is adjacent to the side opposite to the flange of the rotating shaft of the rotor. It is rotatably fitted to the rotary shaft directly or via a bearing.

With this configuration, when the rotating body is rotating, when a magnetic flux is generated by energizing the electromagnetic coil and the armature is magnetically attracted to the rotor,
Since the boss end side of the coil spring that was held at the boss end and was rotating with the rotating body stopped for a moment due to load resistance and the other end continued to rotate, the coil spring contracted due to the twisting action. It is fastened to the boss of the rotating body and the flange of the rotating shaft, and thereafter, the rotation of the rotating body is transmitted to the rotating shaft via the armature and the coil spring, and the rotating shaft is accompanied by the armature, the coil spring and the rotor. Rotate.

[Problems to be solved by the device]

However, in such a conventional electromagnetic spring clutch, since the magnetic circuit is formed in the path from the field core to the disk portion and the boss of the armature, and then to the field core via the rotor, the boss of the armature is Since it is necessary to form a space between the inner hole of the coil bobbin and the coil spring to a depth close to the rotor, as a result, the outer diameter dimension of the coil bobbin becomes large and the outer diameter dimension of the device becomes large in the radial direction. there were.

In addition, if the armature boss is configured deep inside the coil bobbin, the weight of the armature increases and the inertial force also increases.Therefore, there is a problem that abrasion powder is often generated due to frictional sliding contact between the armature and the rotor. It was

Further, since the inner surface of the bottom portion of the field core configured as a fixing member and the side surface of the rotor are in frictional sliding contact with each other, there is a problem that abrasion powder is generated from these frictional sliding surfaces.

The present invention has been made in view of the above points, and makes it possible to reduce the outer diameter of the coil bobbin to downsize the apparatus and to reduce wear particles and improve quality problems. It is an object of the present invention to provide an electromagnetic spring clutch that can be used.

[Means for solving the problem]

In order to achieve such an object, according to the present invention, an armature is fitted to a flange of a rotary shaft and a boss of a rotary body, which have substantially the same diameter and are adjacent to each other, via a coil spring, and one end and the other end of the coil spring are attached to the armature. The rotor is fixed to the boss and the armature of the rotating body respectively, and the rotor adjacent to the side opposite to the boss of the flange is fixed on the rotating shaft, and the electromagnetic coil is wound inside the field core on the equipment side. In the electromagnetic spring clutch in which the coil bobbin is arranged radially outward of the armature, the inner hole of the coil bobbin and the outer peripheral surface of the rotor are formed in a step shape having a large diameter portion and a small diameter portion, respectively, and a small diameter of the coil bobbin is formed. The portion is arranged between the bottom portion of the field core and the large diameter portion of the rotor, and the small diameter portion of the coil bobbin and the small diameter portion of the rotor are rotatably fitted.

[Action]

When the electromagnetic coil is energized and the armature is magnetically attracted to the rotor while the rotating body is rotating, the boss end side of the coil spring that was rotating with the rotating body for one moment is held by the boss end for a moment. Since the coil spring is stopped and the other end continues to rotate, the coil spring is reduced in diameter by a twisting action and clamped to the boss and the flange, and thereafter, the rotation of the rotating body is mediated by the armature and the coil spring. The rotary shaft is transmitted to the rotary shaft and is rotated via the armature and the coil spring, and the rotary shaft rotates together with the armature, the coil spring and the rotor.

In this case, even if the armature and the coil spring are deeply inserted into the inner hole of the coil bobbin, the coil bobbin and the rotor are formed in a stepped shape, so that the space part for winding the electromagnetic coil even in the small diameter part of the coil bobbin. Can be formed, and the entire electromagnetic spring clutch does not become large in the radial direction.

Also, the side surface of the coil bobbin is fixed to the inner surface of the bottom of the field core, and both the small diameter portion and the large diameter portion of the rotor are frictionally slidably contacted with the outer peripheral surface of the small diameter portion and the side surface of the small diameter portion of the rotor. To be done.

Furthermore, the boss of the armature does not have to be exposed to the deepest part of the inner hole of the coil bobbin, the weight of the armature is reduced, and the inertia acting on this armature is reduced,
It is possible to improve the generation of abrasion powder due to frictional sliding contact between the armor and the rotor.

〔Example〕

1 to 3 show an embodiment of an electromagnetic spring clutch according to the present invention. FIG. 1 is a side view showing an upper half of the electromagnetic clutch by breaking it, FIG. 2 is a front view of the same, and FIG. 3 is a coil bobbin. It is an enlarged front view of the principal part shown in order to demonstrate rotation stop. In the figure, reference numeral 1 is a rotating shaft formed of a non-magnetic metal material such as brass in a cylindrical shape, and has a cylindrical shape having a larger diameter than the other parts at the substantially central portion in the axial direction. Is formed on the left side, which has a larger diameter than the right side, on both sides of the flange 2 (hereinafter referred to as the right side and the left side according to FIG. 1). There is provided a screw hole 3 into which a screw for integrating the shaft to be inserted into is screwed.

Reference numeral 4 denotes a rotary body which has a boss 5 having substantially the same diameter as the flange 2 and is rotatably fitted to the rotary shaft 1 with the boss 5 being adjacent to the right side of the flange 2. For example, the rotary body 4 side is driven. On the side, the gear formed on the rotating body 4 is drivingly connected to the driving side. A cylindrical armature 6 is fitted on the outer circumferences of the flange 2 and the boss 5 having substantially the same diameter via a coil spring 7, and the armature 6 can move back and forth in the axial direction of the rotary shaft 1. Has been formed. The coil spring 7 is a spring formed so that a torsion spring force is accumulated by fixing one end and rotating the other end, and one end thereof is fixed to the boss 5 of the rotating body 4,
The other end is engaged with a long groove formed in the armature 6 that can move back and forth.

Reference numeral 8 denotes a rotor which is adjacent to the left side which is the opposite boss side of the flange 2 and which is press-fitted and fixed to the rotary shaft 1 to be integrated therewith, and includes a small diameter portion 8a press-fitted on the outer peripheral surface of the rotary shaft 1 and the flange 2 The large-diameter portion 8b fitted to the outer peripheral surface and the side surface of the is formed in a step shape, and is configured to rotate integrally with the rotating shaft 1. Reference numeral 9 denotes a small diameter portion 9a that fits with the large diameter portion 8a of the rotor 8, a large diameter portion 8b of the rotor 8 and the armature 6.
Is a coil bobbin formed in a step shape with a large-diameter portion 9b facing the electromagnetic coil 10 wound around the coil bobbin 9 in an annular shape with an L-shaped cross section. Is connected to the power supply by. Reference numeral 13 is a pair of detents provided on the coil bobbin 9.

Reference numeral 14 denotes a field core having a bottomed U-shape in which the coil bobbin 9 is provided. A substantially square plate-shaped substrate 14a forming the field core 14 has a detent for engaging with a device fixing portion. 14b is integrally formed. Reference numeral 15 denotes a rectangular plate made of a magnetic material, which is fixed to the bent end of the field core 14, and has a hole into which the armature 6 is inserted. Reference numeral 16 is a groove that engages the detent protrusion 13. Further, the field core 14 is a thrust washer 18
And snap ring 19 keeps it in place.

The operation of the electromagnetic spring clutch configured as above will be described. When the electromagnetic coil 10 is energized while the rotating body 4 is rotating, the field core 14 passes through the rectangular plate 15, the armature 6 and the rotor 8 and then the field core.
A magnetic flux returning to 14 is generated, the armature 6 is magnetically attracted to the rotor 8, and one end of the boss 5 is held by the end of the boss 5.
The end of the coil spring 7 on the rotor 8 side, which was rotating with it, stops momentarily due to the load resistance and the other end continues to rotate. Therefore, the coil spring 7 is reduced in diameter by a twisting action and the boss 5 and the flange 2 are rotated. It is fastened to. After that, the rotation of the rotating body 4 is transmitted to the rotary shaft 1 via the armature 6 and the coil spring 7, and the rotary shaft 1 is rotated by the armature 6.
It rotates with the coil spring 7 and the rotor 8.

In this case, the armature 6 has a cylindrical portion from the rectangular plate 15 to the rotor 8 as a movable iron core portion through which the magnetic flux of the electromagnetic coil 10 flows. In other words, the cylindrical portion of the armature 6 projecting from the rectangular plate 15 to the side of the rotating body 4 is unnecessary in the design, and the weight of the armature 6 can be reduced. Further, the small diameter portion 9a of the coil bobbin 9 and the side surface of the small diameter portion 9a serve as bearing surfaces that are in sliding contact with the rotor 8, and the rotor 8 is rotatably supported by these bearing surfaces, and both the small diameter portion 8a and the large diameter portion 8b of the rotor 8 are supported. Small diameter part 9a of coil bobbin 9
Since the side surface of the coil bobbin is fixed to the side surface of the small diameter portion 9a by frictional sliding contact and the side surface of the coil bobbin is fixed to the inner surface of the bottom portion of the field core, generation of abrasion powder is prevented.

When the electromagnetic coil 10 is de-energized in this state, the armature 6 separates from the rotor 8 and the coil spring 7 is expanded in diameter, so that the boss 5 and the flange 2 are formed by the coil spring 7.
Since the tightening is released, the rotating body 4 continues to rotate, but the rotating shaft 1 stops.

In the present embodiment, the example in which the armature 4 and the field core 14 are formed in a cylindrical shape and a U-shape with a bottom is shown, but the present invention is not limited to this. It may be formed in a V-shaped annular shape and a bottomed tubular shape.

[Effect of device]

As is apparent from the above description, according to the present invention, the cylindrical armature is fitted to the flange of the rotating shaft and the boss of the rotating body, which have the same diameter and are adjacent to each other, via the coil spring, and one end of the coil spring is attached. And the other end are respectively locked to the boss and the armature of the rotating body, the rotor adjacent to the side opposite the boss of the flange is fixed on the rotating shaft, and the electromagnetic coil is installed inside the field core on the equipment side. In an electromagnetic spring clutch in which a wound coil bobbin is arranged outward in the radial direction of an armature, an inner hole of the coil bobbin and an outer peripheral surface of the rotor are formed in a step shape having a large diameter portion and a small diameter portion, respectively. , The small diameter portion of the coil bobbin is arranged between the inner surface of the bottom of the field core and the side surface of the large diameter portion of the rotor, and the small diameter portion of the coil bobbin and the small diameter portion of the rotor are rotatably fitted. By allowed, the small diameter portion of the coil bobbin becomes possible to form a space portion for winding electromagnetic coils it is possible to reduce the diameter of the coil bobbin by that amount, it is possible to miniaturize the entire apparatus in the radial direction.

Further, the side surface of the coil bobbin is fixed to the inner surface of the bottom of the field core, and the small diameter portion and the large diameter portion of the rotor are frictionally slidably contacted with the small diameter portion of the coil bobbin and the side surface of the small diameter portion. It

Furthermore, the armature boss does not have to be exposed to the deepest part of the inner hole of the coil spring, and the armature can be made lighter by changing the shape of the armature to only the movable iron core that serves as the magnetic circuit of the electromagnetic coil. Since the inertial force also becomes small, it is possible to improve the generation of abrasion powder due to the friction sliding of the armature and the rotor.

[Brief description of drawings]

1 to 3 show an embodiment of an electromagnetic spring clutch according to the present invention. FIG. 1 is a side view showing an upper half of the electromagnetic clutch by breaking it, FIG. 2 is a front view of the same, and FIG. 3 is a coil bobbin. It is an enlarged front view of the principal part shown in order to demonstrate rotation stop. 1 ... Rotary axis, 2 ... Flange, 4 ... Rotating body, 5 ...
Boss, 6 ... Armature, 7 ... Coil spring, 8 ...
Rotor, 8a ... small diameter part, 8b ... large diameter part, 9 ... coil bobbin, 9a ... small diameter part, 9b ... large diameter part, 10 ... electromagnetic coil, 14 ... field core.

Claims (1)

[Scope of utility model registration request] 1. An armature is fitted to a flange of a rotary shaft and a boss of a rotary body which have substantially the same diameter and are adjacent to each other via a coil spring, and one end and the other end of the coil spring are connected to the boss of the rotary body and the armature. And to fix the rotor adjacent to the opposite boss side of the flange on the rotating shaft,
In addition, in an electromagnetic spring clutch in which a coil bobbin, which is installed in the field core on the equipment side and around which an electromagnetic coil is wound, is arranged radially outward of the armature, the inner hole of the coil bobbin and the outer peripheral surface of the rotor are respectively large. The coil bobbin is formed in a step shape consisting of a small diameter portion and a small diameter portion, the small diameter portion of the coil bobbin is arranged between the bottom portion of the field core and the large diameter portion of the rotor, and the small diameter portion of the coil bobbin and the small diameter portion of the rotor are rotated. An electromagnetic spring clutch that is freely fitted.