JPH02199322A - Electromagnetic clutch - Google Patents

Abstract

PURPOSE:To improve quietness of a clutch by absorbing vibration of an armature at the time of engagement of the clutch by means of a sheet-like rubber member and putting this sheet-like member between the armature and a metal plate so as to effectively decrease the vibration. CONSTITUTION:On an end surface opposing the side of a suction surface 24 of a clutch rotor 12 of an armature 23, a sheet-like rubber member 26 is stuck, and a steel plate 27 as a metal plate is fixed through the sheet-like rubber member 26. This sheet-like rubber member 26 absorbs vibration of the armature 23 generated by impact on the suction surface of the armature 23 which has been momentarily sucked by the suction surface 24 of the clutch rotor 12 at the time of excitation. In this way, vibration can be effectively decreased and quietness of a clutch can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] <Industrial Application Field> The present invention relates to an electromagnetic clutch, and particularly to an electromagnetic clutch that can reduce operating noise when the clutch is connected.

<Prior Art> Conventionally, various electromagnetic clutches have been used to transmit and interrupt rotational torque, but when the clutch is connected,
Since the armature is instantaneously attracted to the clutch rotor, the armature hits the axial end face of the clutch rotor, and the armature vibrates due to the impact force, producing a relatively loud latch operation noise. In order to reduce this clutch operation noise, for example, Japanese Utility Model Publication No. 61-46263 discloses a mechanism in which a metal plate is attached to the armature to reduce clutch noise.

According to the above structure, the clutch operation noise can be reduced by the allocation effect of the metal plate, but it is desirable to further reduce the clutch operation noise.

<Problems to be Solved by the Invention> Based on this viewpoint, the main object of the present invention is to provide an improved electromagnetic clutch that can reduce clutch operation noise caused by armature vibration during clutch operation. be.

[Structure of the Invention] <Means for Solving the Problems> According to the present invention, such an object is achieved by: an excitation unit;
In an electromagnetic clutch, the electromagnetic clutch includes a rotatable clutch rotor facing the excitation unit, and an armature that is attracted to the clutch rotor and rotates integrally with the clutch rotor when the excitation unit is excited. This is achieved by providing an electromagnetic clutch characterized in that a metal plate is fixed to the end face opposite to the face attracted by the clutch rotor via a rubber sheet-like member.

<Function> In this way, the vibration of the armature can be absorbed by the rubber sheet-like member, and since the rubber sheet-like member is sandwiched between the armature and the metal plate, the rubber sheet-like member The vibration absorption effect is increased.

<Embodiments> Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows a cross section of a main part of an electromagnetic clutch according to the present invention.
A rotating shaft 3 of the compressor is rotatably supported. A threaded portion 4 is formed on the outer periphery of the tip of the rotating shaft 3 that protrudes from the casing 1 to the right in the figure.
For example, a sleeve 5 having radially outward flange portions 6 formed at three locations with equal angular pitches is screwed.

An annular boss portion 7 that surrounds the tip of the rotating shaft 3 is integrally protruded from the casing 1, and a mechanical seal is provided between the inner peripheral surface of the annular boss portion 7 and the rotating shaft 3. It is being This mechanical seal consists of a fixed portion 8 fixed to the inner circumferential surface of the annular boss portion 7 and a rotating portion 9 that rotates integrally with the rotating shaft 3 while resiliently sliding on the fixed portion 8.

This mechanical seal prevents the lubricating oil that lubricates the ball bearing 2 from leaking to the outside.

A clutch rotor 12 is supported on the outer periphery of the boss portion 7 via a double-row ball bearing 11 so as to be coaxial with the rotating shaft 3 and rotatable. An annular groove 13 is coaxially recessed in the end surface of the clutch rotor 12 on the casing 1 side.
An excitation unit 14 is received therein. This excitation unit 14 includes a bracket 1 fixed to the casing 1.
an annular yoke 16 having a C-shaped cross section supported by an annular excitation coil 1 received in the yoke 16;
It consists of 7. A pulley portion 18 consisting of multiple 7-shaped grooves is formed on the outer periphery of the clutch rotor 12. is driven to rotate.

A circular end plate 19 with a recessed center portion is fixed to the flange portion 6 of the sleeve 4 by a rivet 20, and the end plate 19 is secured to the flange portion 6 of the sleeve 4 by a bolt 21 screwed onto the tip of the rotating shaft 3. Extraction has been stopped. An annular armature 23 is attached to the end plate 19 concentrically with the rotating shaft 3 through a plate spring 22 whose one end is riveted to the outer circumference of the end plate 19 and which is coupled to the other end of the plate spring 22 by a rivet 28. ing. The armature 23 is arranged on the end plate 1 so as to face a suction surface 24 formed from the right end surface in the axial direction of the clutch rotor 12 with a predetermined clearance.
It is positioned in the axial direction by a stopper (not shown) provided at 9.

By selectively exciting the excitation coil 17, the armature 23 is magnetically attracted to and magnetically engaged with the attraction surface 24 of the clutch rotor 12, and torque is transmitted between the rotating shaft 3 and the clutch rotor 12. be exposed. In addition, the clutch rotor 12 and the armature 23 are arranged in a staggered manner so that the magnetic flux is passed back and forth between the clutch rotor 12 and the armature 23 in order to increase the attractive force between them. A plurality of arc-shaped slots 25 are provided intermittently in the circumferential direction.

A rubber sheet-like member 26 is adhered to the end face of the armature 23 opposite to the suction surface 24 side of the clutch rotor 12, and a steel plate 27 as a metal plate is adhered via the rubber sheet-like member 26. ing. This rubber sheet-like member 26 is attached to the suction surface 24 of the clutch rotor 12 during excitation.
The armature 23 is momentarily attracted to the suction surface 24.
This is for absorbing vibrations of the armature 23 caused by impact.

Next, the operation procedure of this embodiment will be described below.

When the excitation coil 17 is excited, the armature is magnetically attracted to the attraction surface 24 of the clutch rotor 16 and magnetically engaged, thereby bringing the clutch into a connected state. As described above, the rotation of the clutch rotor 12 driven by the engine is transmitted to the rotating shaft 3 via the armature 23. When this clutch is connected, the clutch rotor 1
Since the armature 23 is instantaneously attracted to and hits the suction surface 24 of 2, the armature 23 vibrates due to the impact force and generates a loud latch operation sound, but the vibration is absorbed by the rubber sheet member 26. Can be absorbed. Further, since the rubber sheet-like member 26 is held between the armature 23 and the steel plate 27, and the rubber sheet-like member 26 is firmly attached to the armature 23,
The vibration of the rubber sheet-like member 26 can be suppressed, the vibration-absorbing effect of the rubber sheet-like member 26 can work effectively, and the clutch operation noise can be further reduced.

FIG. 2 is a diagram similar to FIG. 1 showing a second embodiment. Note that the same parts as in FIG. 1 are given the same reference numerals, and detailed explanation thereof will be omitted. In this second embodiment, an annular peripheral wall portion 31 bent along the axial direction is coaxially formed on the outer peripheral portion of the end plate 19, and
An annular bracket 32 having an L-shaped cross section is fixed to the armature 23 by a rivet 28 and is arranged to surround the entire outer circumference of the peripheral wall 31 at regular intervals in the radial direction. has been done.

An annular cushion rubber 3 is provided on each circumferential wall surface of the circumferential wall portion 31 and the bracket 32 facing each other so as to connect the two.
3 is firmly fixed, and this cushioned rubber 33 performs the function of the leaf spring 22 of the previous embodiment. In addition, on the armature 23 side of the cushioned rubber 33, there is an end plate 1 facing the steel plate 27 fixed to the armature 23.
An inward flange portion 34 extending radially inward along 9 is integrally formed. Therefore, exciting coil 1
When 7 is de-energized, the armature 23 separates from the suction surface 24 of the clutch rotor 12 due to the restoring force of the cushion rubber 33, but since the steel plate 27 comes into contact with the inward flange portion 34, the suction surface 24 of the clutch rotor 12 and the armature 23 is maintained at a predetermined value. Further, since the rubber sheet-like member 26 and the inward flange portion 34 collide with each other via the steel plate 27, it is possible to suitably prevent adhesive force from being generated between the two due to direct contact between the rubber members. In addition, clutch rotor 1
A dust cover 3 is provided on the side of the armature 23 in the center of the ball bearing 11 to prevent dust from entering the ball bearing 11 from the outside.
5 is provided.

In this second embodiment, the clutch operation noise is reduced by the same effect as in the previous embodiment, but in addition, the cushion rubber 3
Since the armature 23 is supported through the cushion rubber 33, the vibration absorption effect by the cushion rubber 33 can also be obtained.

In addition, in each embodiment, the rubber sheet-like member 2 which is separate from each other is used.
6 and the steel plate 27 were used, but for example, the armature 2 is made by baking a rubber material on the metal plate in advance and integrating it with the metal plate.
It may be fixed to 3.

[Effects of the Invention] As described above, according to the present invention, the vibration of the armature when the clutch is connected is absorbed by the rubber sheet-like member, and the rubber sheet-like member is sandwiched between the armature and the metal plate. As a result, the vibration absorption effect of the rubber sheet-like member can be increased, vibration can be effectively reduced, and clutch operation noise can be reduced, making the clutch quieter. .

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a main part of an electromagnetic clutch according to the present invention along the axial direction. FIG. 2 is a diagram similar to FIG. 1 showing a second embodiment. 1...Casing 2...Ball bearing 3...Rotating shaft 4...Threaded part 5...Sleeve
6...Flange part 7...Annular boss part 8...
Fixed part 9... Rotating part 11... Ball bearing 1
2...Clutch rotor 13...Groove portion 14...Excitation unit 15...Bracket 16...Yoke
17... Excitation coil 18... Pulley part 1
9... End plate 20... Rivet 21... Bolt 22... Leaf spring 23... Armature 2
4... Suction surface 25... Slot 26...
Rubber sheet member 27... steel plate 28... rivet 31...
- Peripheral wall part 32...Bracket 33...Cushion rubber 34...Inward flange part 35...Dust cover

Claims (1)

[Scope of Claims] An excitation unit, a rotatable clutch rotor facing the excitation unit, and an armature that is attracted to the clutch rotor and rotates integrally with the clutch rotor when the excitation unit is excited. An electromagnetic clutch having: a metal plate fixed to an end surface of the armature opposite to a surface attracted by the clutch rotor via a rubber sheet-like member.