JP2914604B2 - Electromagnetic coupling device - Google Patents

Abstract

PURPOSE:To enable the positive operation of an automatic gap adjusting device in any service condition. CONSTITUTION:A collar part 19c is formed at a torque transmission pin 19 fitted into the through hole of an armature hub 16, and the end part of a spring pin 22 press-fitted into another through hole of the armature hub 16 is fixed to the collar part 19c. When a gap G between an armature 13 and a rotor 3 is increased by wear, the inner bottom face of the through hole of the armature 13 collides with the head part of a headed locking member 19, and the torque transmission pin 19 is pulled out onto the rotor 3 side by the increase part of the gap G against the sliding resistance of the spring pin 22 by the magnetic attraction movement of the armature 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic coupling device having an automatic air gap adjusting device such as an electromagnetic clutch or an electromagnetic brake.

[0002]

2. Description of the Related Art As a conventional electromagnetic coupling device having an automatic air gap adjusting device, one disclosed in Japanese Utility Model Publication No. Sho 59-5238 is representative. A field core in which an electromagnetic coil is insulated and fixed by an insulating resin or the like, and a rotor in which an annular groove in which the front surface of the field core is fitted and formed is rotatably supported via a bearing in the field core. ,
An armature facing the friction surface of the rotor with a predetermined gap, a leaf spring having a free end fixed to the armature with rivets, an automatic gap adjusting device having a base end of the leaf spring fixed; It has a structure including an armature hub on which the automatic air gap adjusting device is arranged. The automatic air gap adjusting device is inserted through a torque transmitting pin having a rubber O-ring as a sliding resistance member and a stepped through hole formed in the armature, and is inserted into a base end of the leaf spring. It consists of a bolt as a headed locking member having a screw portion screwed into the screw hole of the torque transmission pin through the drilled mounting hole, and the torque transmission pin is inserted into the through hole of the armature hub via an O-ring. The press-fitting is performed, and the power to the electromagnetic coil is cut off between the head of the bolt fixing the base end of the leaf spring to the torque transmission pin and the inner bottom surface formed in the stepped through hole of the armature. A gap equal to the gap formed between the armature and the rotor when leaned is set.

An electromagnetic clutch having such a structure is
By energizing the electromagnetic coil, the armature is magnetically attracted to the rotor against the spring force of the leaf spring and frictionally engaged, so that the rotation of the drive shaft on which the rotor is mounted is transmitted to the driven shaft on which the armature hub is mounted. You. When the power supply to the electromagnetic coil is cut off, the armature is separated from the rotor by the spring force of the leaf spring, so that the rotation transmission from the drive shaft to the driven shaft is cut off. When the friction between the armature and the rotor is worn due to the repetition of such an operation and the gap between the armature and the rotor is increased when the power to the electromagnetic coil is cut off, the electromagnetic coil The magnetic resistance in the magnetic circuit increases, and the suction time of the armature becomes longer, thereby deteriorating the operation characteristics. Hit
The increase in the gap against the sliding resistance force by the O-ring,
Since the torque transmitting pin is pulled out from the through hole of the armature hub, the air gap is automatically adjusted, so that stable operating characteristics can always be maintained.

On the other hand, as an electromagnetic coupling device having an automatic gap adjusting device having a structure in which a predetermined gap is formed between the inner bottom surface of the through hole of the armature and the head of the headed locking member, Japanese Utility Model Application No. 58-63799 (Japanese Utility Model Application No. 59-63)
No. 168026) Some of the electromagnetic brakes disclosed in the specification and the drawings at the time of filing the application, and the electromagnetic brake described as an embodiment in the specification and FIG. 5 include an armature hub, a boss portion formed with spline grooves and an axis line. An inner hub composed of a flange portion having a through hole formed in the direction, a boss portion having a spline groove and a through hole formed in the axial direction, and a screw hole formed in the axial direction. After the inner hub and the outer hub are spline-fitted to each other, the inner hub and the outer hub are spline-fitted. A spring pin as a sliding resistance member is press-fitted.

[0005] In the screw hole of the flange portion of the outer hub, a screw portion of a bolt as a headed locking member inserted from a stepped through hole of the armature and passing through a mounting hole at the base end of the leaf spring. A gap equal to the gap formed between the armature and the field core (rotor in the case of an electromagnetic clutch) is set between the bolt head and the inner bottom surface of the through hole of the armature. I have. In the electromagnetic brake having such a structure, since the field core is configured as a fixed member, the armature hub is formed by energizing the electromagnetic coil and magnetically attracting the armature to the field core against the spring force of the leaf spring. The braked shaft on which is mounted is braked and rotation stops. Further, when the power supply to the electromagnetic coil is cut off, the armature is separated from the field core by the spring force of the leaf spring, so that the brake on the braked shaft is released and becomes rotatable.

When the frictional engagement surface between the armature and the field core is worn due to the repetition of such an operation, and the gap between these members becomes large when the power supply to the electromagnetic coil is cut off, the armature becomes in the field. When magnetically attracting to the core, the inner bottom surface of the through hole of the armature is hit against the head of the bolt, and the outer hub is placed in the field relative to the inner hub by an amount corresponding to the increase in the gap against the sliding resistance force of the spring pin. Since the air gap moves to the core side, the air gap is automatically adjusted, and stable operating characteristics can always be maintained.

[0007]

Among the conventional electromagnetic coupling devices, the electromagnetic clutch disclosed in Japanese Utility Model Publication No. 59-5238 has a rotor side rotation from an armature through a leaf spring, and a torque transmission pin of an automatic air gap adjusting device and a sliding resistance. It becomes a power transmission path transmitted to the armature hub through the member, and the driving torque acts on the sliding resistance member made of the elastic member, so that the deterioration is caused at an early stage. Depending on severe use conditions, there is a problem that reliable operation of the automatic air gap adjusting device becomes impossible.

In the electromagnetic brake disclosed in Japanese Utility Model Application No. 58-63799, a shaft to be braked is connected to an outer hub spline-fitted to an inner hub, and the braking torque when the armature is magnetically attracted to the field core is spline-fitted. The structure is such that it does not act on the sliding resistance member that has been absorbed by the joint portion and press-fitted between the inner hub and the outer hub. However, in the electromagnetic coupling device having such a spline fitting portion, there is a problem that the device cannot be provided at a low cost in view of processing time and processing cost of the spline groove. SUMMARY OF THE INVENTION It is an object of the present invention to provide an inexpensive electromagnetic coupling device capable of reliably operating an automatic air gap adjusting device under any use conditions.

[0009]

According to a first aspect of the present invention, a threaded portion of a headed locking member is provided with a stepped through-hole of an armature to form a leaf spring. It has a structure that is inserted into the mounting hole and screwed and fixed to the screw hole of the torque transmission pin fitted into the through hole of the armature hub, and protrudes from the through hole of the armature hub to the armature side or the side opposite to the armature. A flange portion is provided on the torque transmission pin thus formed, and a slide resistance member fixed to the flange portion is press-fitted into another through hole formed in the armature hub.

According to a second aspect of the present invention, a cushioning member is interposed between the outer peripheral surface of the torque transmitting pin and the inner peripheral surface of the through hole of the armature hub in which the torque transmitting pin is fitted. Features. Further, as a third invention, the sliding resistance member according to the first invention or the second invention is press-fitted into a metal material cylindrical member which is press-fitted and prevented from being inserted into another through hole of the armature hub via a buffer member. It is characterized by being fitted.

[0011]

In an electromagnetic coupling device having such an automatic air gap adjusting device, for example, in the case of an electromagnetic clutch, when an electromagnetic coil is energized to magnetically attract an armature to a rotor,
The rotation on the rotor side is transmitted to the armature hub via the armature, the leaf spring, and the torque transmission pin of the automatic air gap adjusting device, and no driving torque acts on the sliding resistance member of the automatic air gap adjusting device. Similarly, also in the electromagnetic brake, since the braking torque does not act on the sliding resistance member, the automatic gap adjusting device can be reliably operated.

[0012]

1 to 4 show an embodiment of the electromagnetic coupling device according to the present invention. FIG. 1 is a front view of an electromagnetic clutch, FIG. 2 is a sectional view taken along line AA of FIG. 1, and FIG. FIG. 4 is an enlarged view of a main part around a pin, and FIG. 4 is an enlarged view of a main part around a sliding resistance member.
Hereinafter, embodiments will be described with reference to these drawings.

An electromagnetic clutch 1 as an electromagnetic coupling device shown in these drawings is mounted on a drive shaft 2 of a general industrial machine and used as a power transmission device to a driven side. Code 3
Is a rotor which is key-fitted to the drive shaft 2 and whose movement in the axial direction is restricted. A field core 6 having a U-shaped cross-section to which a vibrating plate 5 is fixed and having a front face fitted into an annular concave portion of the flange 3b is attached to the boss 3 of the rotor 3.
a is supported via a bearing 7. Field core 6
Is provided with an electromagnetic coil 8 insulated and fixed with an insulating resin in an annular concave portion opened on the front side. The field core 6 is fixed by screwing a mounting plate 9 welded to the rear surface to a housing of a general industrial machine (not shown).

The boss 3a of the rotor 3 is mounted on the drive shaft 2.
A pair of bearings 11 is fitted via a collar 10 in contact with the end surface, and the armature assembly 12
It is supported rotatably. Armature assembly 12
Is an armature 13 having a friction engagement surface facing a front surface (friction engagement surface) of the flange portion 3b of the rotor 3 with a predetermined gap G, and a free end fixed to the armature 13 with a rivet (not shown). Ring-shaped or rectangular leaf spring 14, an automatic gap adjusting device 15 to which the base end of the leaf spring 14 is fixed, an armature hub 16 on which the automatic gap adjusting device 15 is arranged, and an armature hub 16 has a pulley 17 fixed integrally with a bolt (not shown). Reference numeral 18 denotes a vibration damping rigid plate fixed to the armature 13. The armature hub 16 of this embodiment has a boss 1 made of a steel material into which the bearing 11 is press-fitted.
6a, an aluminum-made flange 16b integrally formed on the outer periphery of the boss 16a by insert molding, and a flange 16b arranged at a position equally divided into three in the circumferential direction.
And a collar 16c made of a metal material and fixed integrally to the collar.

The automatic gap adjusting device 15 includes a screw hole 19a, two annular grooves 19b, and a flange 19c formed at an end of the armature hub 16 protruding from the collar 16c.
And a torque transmitting pin 19 made of a rubber material O-ring 20 (a metal-made corrugated ring spring may be used) as a buffer member fitted into the annular groove 19b. Each color 16c of the armature hub 16
Press fit. Further, the torque transmission pin 19 is inserted into the screw hole 19a of the armature 13 from the through hole 13a having an outer diameter opening through the through hole of the damping steel plate 18 and the mounting hole at the base end of the leaf spring 14. A screw portion 21a of a bolt 21 as a headed locking member is screwed and fixed. The bolt 21 has a neck portion 21 b for holding and fixing a peripheral edge of a mounting hole formed in a base end portion of the leaf spring 14 on an end surface of the torque transmission pin 19, and a through hole 13 of the armature 13.
The head 21c is opposed to the inner bottom surface 13b formed at a with a predetermined gap g.

A cylindrical fastening portion 1 is provided at both ends of a flange portion 19c extending in both circumferential directions of the torque transmitting pin 19.
9d is formed, and an end of a spring pin 22 as a sliding resistance member is press-fitted and fixed to each fastening portion 19d. The other end of the spring pin 22 is press-fitted into a through hole of a cylindrical member 23 made of a metal material. In addition, the cylindrical member 23 is connected to the flange portion 16b of the armature hub 16 via a rubber O-ring 24 (a metal ring spring may be used) as a buffer member fitted into the annular groove on the outer peripheral surface. It is press-fitted into the drilled through hole. Note that one end of the cylindrical member 23 is connected to the armature hub 16.
The armature hub 16 is fixed by being brought into contact with the inner flange portion of one of the through-hole openings, and the other end thereof is prevented from coming off by a ring 25 fitted into the other through-hole opening of the armature hub 16.

The electromagnetic clutch 1 having the above structure
When the electromagnetic coil 8 is energized, the magnetic flux
From the rotor 3, and from the rotor 3 to the armature 13 through the gap G, and from the rotor 3 to the field core 6.
, The armature 13 is magnetically attracted to the rotor 3 against the spring force of the leaf spring 14. The rotation of the drive shaft 2 is transmitted from the rotor 3 to the armature 1.
3, and the armature hub 16 and the pulley 1 through the leaf spring 14 and the torque transmission pin 19 of the automatic air gap adjusting device 15.
7 is transmitted. Since the magnetic flux disappears when the power supply to the electromagnetic coil 8 is stopped, the armature 13 is separated from the rotor 3 by the spring force of the leaf spring 14, and the rotation transmission is cut off.

By repeating such an operation, the frictional engagement surface between the rotor 3 and the armature 13 is worn and the gap G
When the armature 13 magnetically moves to the rotor 3 when the armature 13 moves, the inner bottom surface 13b of the through hole 13a of the armature 13 is hit against the head 21c of the bolt 21, and the torque transmission pin 19 is increased by the amount of the gap G. The air gap G is automatically adjusted because it is towed toward the rotor 3. In the electromagnetic clutch 1 of this embodiment, the driving torque is applied to the outer peripheral surface of the torque transmitting pin 19 and the collar 1 of the armature hub 16.
6c, but acts as a cushioning member.
Since the ring 20 is interposed, the impact on the outer peripheral surface and the inner peripheral surface is reduced. Further, the micro vibration of the armature 13 due to the frictional engagement of the members 13 when the armature 13 is magnetically attracted to the rotor 3 is absorbed by the leaf spring 14 and the O-ring 20, so that the generation of squealing noise is small. Particularly in this embodiment, the armature 13 is provided with a damping steel plate 18,
Further, since the damping steel plates 5 are fixed to the rotor 3, the generation of unpleasant squeals is extremely small.

On the other hand, in the electromagnetic clutch 1 of this embodiment,
Since the spring pin 22 as the sliding resistance member is inserted into the through hole of the armature hub 16 via the O-ring 24 as the cushioning member, the spring pin 2
2 is absorbed by the O-ring 24. In the above embodiment, the flange 19c of the torque transmission pin 19 is connected to the armature hub
5 and FIG. 6, as shown in the enlarged view of the main part corresponding to FIG. 3 and FIG.
9c may be configured on the armature 13 side, and the same operation and effect can be obtained. In these embodiments, the same components as those in the previous embodiment are denoted by the same reference numerals, and description thereof is omitted. In addition, in this embodiment, the electromagnetic clutch has been described as the electromagnetic coupling device.
Can be applied to an electromagnetic brake for magnetically attracting the magnetic field to the field core 6. Further, the flange portion of the torque transmission pin extends in both circumferential directions, and sliding resistance members are formed at both ends of the flange portion. However, the present invention is not limited to this. A flange may be formed on the pin so as to extend in the radial direction, and a sliding resistance member may be formed on the outside, inside, or both sides of the flange in the radial direction.

[0020]

As described above, in the electromagnetic coupling device according to the present invention, as a first invention, a flange portion is provided on a torque transmitting pin projecting from the through hole of the armature hub to the armature side or the side opposite to the armature. Since the sliding resistance member fixed to the flange portion is press-fitted into another through hole of the armature hub, no driving torque or braking torque acts on the sliding resistance member, and the automatic operation of the automatic gap adjusting device is ensured. Becomes possible. In addition, since there is no spline fitting structure unlike the conventional electromagnetic coupling device, the electromagnetic coupling device can be provided at low cost.

Further, in the second invention, in the first invention, a buffer member is interposed between the outer peripheral surface of the torque transmitting pin and the inner peripheral surface of the through hole of the armature hub. The outer peripheral surface and the inner peripheral surface are not deformed and the slidability of the torque transmitting pin does not deteriorate.
Also, the shock absorbing member can absorb the micro vibration of the armature when the rotor and the field core are frictionally engaged, and can reduce the unpleasant squeal. According to a third aspect, in the first and second aspects,
Since the sliding resistance member is press-fitted into another through-hole of the armature hub via a cushioning member and is fitted into the metal cylindrical member which is press-fitted and prevented, the sliding resistance member is deformed by the driving torque or the braking torque. There is no such thing. Therefore, it is possible to provide an electromagnetic coupling device that enables more reliable operation of the automatic air gap adjusting device.

[Brief description of the drawings]

FIG. 1 is a front view of an electromagnetic clutch according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is an enlarged view of a main part around a torque transmission pin of FIG. 2;

FIG. 4 is an enlarged view of a main part around a sliding resistance member of FIG. 2;

FIG. 5 is another embodiment of the present invention, and is an enlarged view of a main part around a torque transmission pin corresponding to FIG. 3;

6 is another embodiment of the present invention, and is an enlarged view of a main part around a sliding resistance member corresponding to FIG. 4. FIG.

[Description of Signs] 15 Automatic air gap adjusting device 19 Torque transmission pin 21 Bolt as headed locking member 22 Spring pin as sliding resistance member

Continuation of the front page (56) References Japanese Utility Model Showa 59-168026 (JP, U) Japanese Utility Model Showa 63-1009038 (JP, U) Japanese Utility Model Showa 61-22935 (JP, U) Japanese Utility Model Showa 61-524 (JP) , U) Jikai Hei 7-32233 (JP, U) Jiko 59-5238 (JP, Y2) (58) Fields investigated (Int. Cl. ⁶ , DB name) F16D 27/112 F16D 65/54

Claims (3)

(57) [Claims] 1. An armature in which a plurality of stepped through holes are formed at intervals in a circumferential direction, a leaf spring having a free end fixed to the armature, and a base end of the leaf spring. A neck abutting on the periphery of the mounting hole drilled in the head, a head facing the inner bottom surface formed in the through hole of the armature with a predetermined gap, and the head of the neck. A plurality of headed locking members having a screw portion formed on the opposite side, and a plurality of torque transmission pins having screw holes into which the screw portions of these headed locking members are screwed, An armature hub having a through hole into which the torque transmission pin is fitted, wherein the screw portion of the headed locking member is inserted from the through hole of the armature into the mounting hole of the leaf spring, and the torque transmission is performed. In the electromagnetic coupling device screwed into the screw hole of the pin, A flange is provided at an end of the torque transmission pin protruding from the through hole of the armature hub to the armature side or the side opposite to the armature, and a sliding resistance member fixed to the flange is attached to the armature hub. An electromagnetic coupling device, wherein the electromagnetic coupling device is press-fitted into another through hole. 2. The electromagnetic member according to claim 1, wherein a buffer member is interposed between an outer peripheral surface of the torque transmission pin and an inner peripheral surface of a through hole of the armature hub into which the torque transmitting pin is fitted. Coupling device. 3. The sliding resistance member is press-fitted into a metal cylindrical member which is press-fitted and prevented from being inserted into another through hole of the armature hub via a buffering member. Or the electromagnetic coupling device according to 2.