JPH10184730A - Electromagnetic clutch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a noise generated in the attracting time and the removing time of an armature plate. SOLUTION: This electromagnetic clutch 1 is installed to a rotary shaft 2, and it furnishes a hub 10 having a flange 11; an armature plate 30 attracted to a rotor 20 in the exciting time; and a plate spring 40 to restore the armature plate 30 to the original position in the nonexciting time. In this case, a rivet 70 inserted to the insertion hole 42a of the spring member 40, and fixed to the armature plate 30; and a rubber stopper 50 holding a part of the spring member 40, and installed on the outer peripheral surface of the rivet 70; are provided, and a projection to contact with the armature plate 30 is provided on the end face at the clutch side of the rubber stopper 50.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic clutch, and more particularly to an electromagnetic clutch having an armature vibration damping structure.

[0002]

2. Description of the Related Art Conventionally, as an electromagnetic clutch having an armature anti-vibration structure, there is known an electromagnetic clutch described in Japanese Utility Model Publication No. 2-1541.

FIG. 6 is a longitudinal sectional view showing a part of a conventional electromagnetic clutch.

An elastic member 100 is pressed into a stopper plate 111 fixed to a hub (not shown).
The shape of the head of the elastic member 100 is trapezoidal in cross section. A through hole 110d is formed in the center of the elastic member 100, and a collar 113 is inserted into the through hole 110d. A stopper pin 112 is screwed into the screw hole 108a of the armature plate 108 via the collar 113, and the elastic member 100 is fixed to the armature plate 108. The elastic member 100 is connected to the head flange 112a of the stopper pin 112 and the armature. It is sandwiched between the plates 108 (see Japanese Utility Model Publication No. 2-1541).

According to the electromagnetic clutch, during excitation, the armature plate 108 is attracted to the friction surface of the rotor 103 against the elastic force of the spring member (fixed to the hub together with the stopper plate 111). The contact area between the head of the elastic member 100 and the flange 112a of the stopper pin 112 gradually increases, and the elastic member 100
Since the compression reaction force of the armature plate 108 increases, the suction speed of the armature plate 108 decreases, and the impact sound at the time of suction decreases.

[0006]

However, in the above-described electromagnetic clutch, the elastic member 100 is connected to the stopper plate 111.
Since the configuration is adopted in which the elastic member 100 is press-fitted into the hole 111a, it is necessary to largely deform the elastic member 100 when attaching to the stopper plate 108, and it is difficult to attach the elastic member 100 having high hardness. Therefore, the most appropriate high elastic member cannot be selected.

When the armature plate 1 is not energized,
08 is released from the restraint by the excitation, moves away from the rotor 103 and accelerates in the direction of the stopper plate 110, and collides with the elastic member 100 of the stopper plate 110. At this time, the armature plate 108 collides with the entire bottom surface of the elastic member 100, and the impact force at the time of the collision is transmitted to the hub via the elastic member 100, generating a large impact sound (separation sound). Also armature plate 1
08 and some elastic space between the elastic member 100,
The armature plate 108 vibrates in the gap and generates a vibration sound.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide an electromagnetic clutch that can reduce noise generated when an armature plate is attracted and detached.

[0009]

In order to solve the above-mentioned problems, an electromagnetic clutch according to the first aspect of the present invention is provided with a hub mounted on a rotating shaft and having a flange portion, and an armature plate which is attracted to a rotor when excited. A non-energized electromagnetic clutch having a spring member for returning the armature plate to the home position, wherein a fastening member inserted into the insertion hole of the spring member and fixed to the armature plate; An elastic member mounted on the outer peripheral surface of the fastening body with a part thereof sandwiched therebetween, and a protrusion that comes into contact with the armature plate is provided on a clutch-side end surface of the elastic member.

At the time of excitation, when the armature plate moves toward the rotor against the elastic force of the spring member, the fastener also moves toward the rotor at the same time, and the elastic member is compressed. At this time, the kinetic energy of the armature plate in the direction of the rotor is absorbed by the increase of the compression reaction force of the elastic member in the direction of the origin, and the moving speed is suppressed.

When the armature plate moves away from the rotor due to the elastic force of the spring member during non-excitation, the fastener also moves away from the rotor at the same time.
At this time, since the protrusion of the elastic member is always in contact with the armature plate, the elastic member attenuates the vibration of the armature plate. Further, since the armature plate compresses the elastic member from the protrusion, the elastic member gradually receives the force at the time of detachment from the armature plate, and the detachment speed and detachment force from the rotor are suppressed.

According to a second aspect of the present invention, there is provided the electromagnetic clutch according to the first aspect, wherein the elastic member has a cut which can be engaged with a part of the spring member, and the cut is perpendicular to the cut and the fastening is performed. A through hole for attaching a body is formed.

The elastic member can be easily sandwiched between the spring member only by engaging a part of the spring member with the cut of the elastic member.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

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

The electromagnetic clutch 1 includes a rotating shaft 2 of a refrigerant compressor.
, A hub 10 having a flange 11, a rotor 20 which is rotated by a rotational force from an engine (not shown) around a rotation shaft 2 of the refrigerant compressor, and a rotor 20 which is energized when an electromagnetic coil 21 is energized. The armature plate 30 which is adsorbed on the armature plate and the electromagnetic coil 21 interposed between the flange portion 11 of the hub 10 and the armature plate 30
And a leaf spring (spring member) 40 for returning the armature plate 30 to the home position when no current is supplied.

A pulley 60 is fixed to the outer peripheral surface of the rotor 20, a V-belt (not shown) is wound around the pulley 60, and the rotor 20 is connected to a crankshaft of the engine via the V-belt.

The rubber stopper (elastic member) 50 is
Stepped rivet 7 fixed to armature plate 30
It is attached to the leaf spring 40 by 0 (fastener).

FIG. 2 is a plan view of the armature plate, and FIG. 3 is a sectional view taken along line III-III in FIG.

The armature plate 30 is made of, for example, low carbon steel, and includes an annular portion 31 and a disk portion 33 formed inside the annular portion 31 with a magnetic interception portion 32 interposed therebetween. In the annular portion 31, insertion holes 31a are formed on the same circumference around the rotation shaft 2 at intervals of 120 °.

Each of the three leaf springs 40 is made of, for example, low carbon steel, and includes a substantially circular annular portion 41 and a tongue piece 42 projecting from the annular portion 41 toward the center. Three insertion holes 41a, 42a, 42b are formed in the diameter direction of the annular portion 41.

The flange portion 11 connected to the rotating shaft 2 has an annular shape, and insertion holes 11a are formed on the same circumference around the rotating shaft 2 at intervals of 120 °.

The rivet 12 is inserted into the insertion hole 42b and the insertion hole 11a, and the rivet 12 is swaged to fix a part of the leaf spring 40 to the lower surface of the flange portion 11.

A rivet 15 is inserted into the insertion hole 31a and the insertion hole 41a, and the rivet 15 is caulked to fix a part of the leaf spring 40 on the upper surface of the annular portion 31 of the armature plate 31.

A rubber stopper 50 is inserted from the side (the upper side in the figure) of the leaf spring 40, the tongue piece 42 of the leaf spring 40 is sandwiched by the rubber stopper 50, and the rubber stopper 50 is stepped through the rubber stopper 50 and the leaf spring 40. The rivet 70 is inserted into the armature plate 30 and the stepped rivet 70 is swaged.
At this time, the protrusion (described later) of the rubber stopper 50 is swaged by the stepped rivet 70 to thereby armature plate 30.
Presets are applied so that there is no backlash when pressed against.

FIG. 4A is a plan view of the rubber stopper, and FIG.
(B) is a longitudinal sectional view thereof.

The rubber stopper 50 is formed of an upper elastic portion 50a having a trapezoidal cross section and a lower elastic portion 50b having a rectangular cross section.

Two projections 51a and 51b are provided on the lower surface (clutch side end surface) of the lower elastic portion 50b facing the armature plate 30. A cut 52 having substantially the same shape as the tongue piece portion 42 in a plan view is formed in the lower elastic portion 50b.

The upper surface of the upper elastic portion has substantially the same circular shape as the flange portion 71 (see FIG. 3) of the stepped rivet 70, and the stepped rivet 70 is provided at the center in a direction perpendicular to the cut 52. A through hole 53 for attachment is formed.

FIGS. 5A and 5B are partially enlarged sectional views of the electromagnetic clutch for explaining the operation of the rubber stopper.

When the armature plate 30 moves in the direction of the rotor 20 against the elastic force of the leaf spring 40, the rivet 70 also moves in the direction of the rotor 20 at the same time. The stopper 50 is gradually compressed (see FIG. 5B).

The elastic reaction force of the upper elastic portion 50a is increased by the compression toward the rotor 20, and the kinetic energy of the armature plate 30 is absorbed by the elastic reaction force of the upper elastic portion 50a and the elastic force of the leaf spring 40. Therefore, the moving speed is suppressed, and the moving speed is reduced at the time of collision with the rotor 20, so that the impact sound at the time of the collision is reduced. At the same time, the vibration at the time of collision which cannot be absorbed by the leaf spring due to the characteristics of the rubber of the rubber stopper 50 is absorbed.

When the armature plate 30 moves away from the rotor 20 by the elastic force of the leaf spring 40, the stepped rivet 70 also moves away from the rotor 20 at the same time. At this time, the protrusion 5 of the rubber stopper 50
Since 1a and 51b are always in contact with the armature plate 30 (see FIG. 5B), the projections 51a and 51b
The rubber stopper 50 is gradually compressed from the position where the rubber stopper 50 is in contact with the upper surface of the armature plate 30 (FIG. 5).
(See (a)), the moving speed (separation speed) of the armature plate 30 can be reduced as in the case of the suction, and the vibration at the time of collision is absorbed.

According to this embodiment, the following effects are exhibited.

Projections 50a, 50b of rubber stopper 50
Since the armature plate 30 and the armature plate 30 are always in pressure contact with each other, the impact force caused by the collision between the armature plate 30 and the rubber stopper 50 when the armature plate 30 separates can be suppressed, and the impact noise can be reduced.

Since the leaf spring 40 is sandwiched between the rubber stoppers 50, the volume of the rubber stopper 50 can be increased, and the impact force at the time of suction and detachment can be more reliably absorbed and the impact noise can be reduced. Can be smaller.

The rubber stopper 50 is attached to the leaf spring 40, and a stopper plate 111 for attaching the rubber stopper 100 required in the conventional arrangement is provided.
Is omitted, the number of parts can be reduced.

Since the rubber stopper 50 is sandwiched between the leaf springs 40 and attached, any one having an arbitrary hardness can be selected, and the rubber stopper 50 having an optimum hardness with the greatest effect of reducing the impact sound is adopted. be able to.

In this embodiment, the case where the rubber stopper 50 is used as the elastic member has been described. However, a resin material may be used as long as it has elasticity.

[0040]

As described above, according to the electromagnetic clutch of the first aspect of the present invention, when the armature plate moves toward the rotor against the elastic force of the spring member during the attraction, the origin of the rubber stopper is reduced. Kinetic energy in the direction of the rotor is absorbed by the increase in the compression reaction force in the position direction, and the moving speed is suppressed. On the other hand, when the armature plate is moved away from the rotor by the elastic force of the spring member at the time of separation, the vibration of the armature plate is attenuated by the rubber stopper that is always in contact with the armature plate. In addition, since the armature plate compresses the rubber stopper from the protrusion, the detachment speed from the rotor can be suppressed.

Therefore, at the time of suction, the armature plate is decelerated and collides with the rotor, and at the time of detachment, the armature plate is decelerated and collides with the bottom surface of the rubber stopper. Withdrawal noise decreases together.

According to the electromagnetic clutch of the present invention, it is possible to easily attach the spring member to a part of the spring member simply by engaging the part of the spring member with the cut of the elastic member.
The number of parts can be reduced and the electromagnetic clutch can be manufactured at low cost.
You.

[Brief description of the drawings]

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

FIG. 2 is a plan view of an armature plate.

FIG. 3 is a sectional view taken along line III-III in FIG. 2;

FIG. 4A is a plan view of a rubber stopper, and FIG.
(B) is a longitudinal sectional view thereof.

FIGS. 5A and 5B are partially enlarged cross-sectional views of an electromagnetic clutch illustrating an operation of a rubber stopper.

FIG. 6 is a longitudinal sectional view showing a part of a conventional electromagnetic clutch.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electromagnetic clutch 2 Rotating shaft 10 Hub 11 Flange part 20 Rotor 30 Armature plate 40 Leaf spring (spring member) 42a Insertion hole 50 Rubber stopper (elastic member) 51a, 51b Projection part 52 Cut 53 Through hole 70 Rivet (fastened body)

Claims (2)

[Claims] 1. A hub mounted on a rotating shaft and having a flange portion, an armature plate which is attracted to a rotor when excited, and a spring member which returns the armature plate to an origin position when not excited. An electromagnetic clutch, comprising: a fastening member inserted into the insertion hole of the spring member and fixed to the armature plate; and an elastic member attached to an outer peripheral surface of the fastening member with a part of the spring member sandwiched therebetween. An electromagnetic clutch, wherein a projection that contacts the armature plate is provided on a clutch-side end surface of the elastic member. 2. The elastic member is provided with a cut which can be engaged with a part of the spring member, and a through-hole which is orthogonal to the cut and for attaching the fastening body. The electromagnetic clutch according to claim 1.