JPH05133426A - Electromagnetic clutch - Google Patents

Abstract

PURPOSE:To increase the outside diameter of a cushion rubber and improve durability by eliminating conventional rivet-fixing which needs a large space. CONSTITUTION:A circular outer plate 12 is mounted on the outside periphery of an inner hub 13 which transmits rotational force to a shaft for compressor, and the outside peripheral wall of the inner hub 13 and the inner peripheral wall of the outer plate 12 are jointed to each other by a cushion rubber 18. Moreover, a rotor 2 which is a cushion rubber 18. Moreover, a rotor 2 which is rotatably-supported to a housing rotates by receiving the rotational force transmitted to a pulley 4 through a belt. An armature 9 is installed facing the rotor 2 so that, it may be connected and disconnected to/from the rotor. A fixing part 15 which extends in an axial direction of the outer plate 12 is fixed. When an exciting coil 1 is energized, the armature 9 is attracted to the rotor 2 against the elastic force of the cushion rubber 18.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic clutch used for the intermittent action of power transmission.

[0002]

2. Description of the Related Art Some electromagnetic clutches of compressors used in automobile air conditioners are provided with cushion rubber for the purpose of absorbing torque fluctuations. In this type of electromagnetic clutch, an outer plate is provided on the outer peripheral portion of the cushion rubber, and an armature is fixed to the outer plate by rivets.

[0003]

According to such a conventional electromagnetic clutch, when the pulley diameter is small, it is necessary to secure a space required for fixing the rivet. Therefore, the outer diameter of the cushion rubber is as large as the space is secured. Is limited. Therefore, when the outer diameter of the cushion rubber is limited, in order to give the cushion rubber an axial elastic force smaller than the elastic force corresponding to the suction force of the clutch, the inner diameter of the cushion rubber is made smaller or the cushion rubber has a smaller thickness. There is a problem that durability becomes low due to the need to reduce the thickness.

The present invention has been made in order to solve such a problem. The conventional rivet fixing which occupies a large space is eliminated, the outer diameter of the cushion rubber is increased, and the intermittent action of power is improved. It is an object of the present invention to provide an electromagnetic clutch having such a structure.

[0005]

An electromagnetic clutch according to the present invention for achieving the above object is provided with a rotor rotatably supported by a housing and rotating by receiving a rotational force from a drive unit. An armature arranged to be able to come into contact with and separate from the rotor, an exciting coil for attracting the armature to the rotor in an energized state, an inner hub for transmitting a rotational force to a driven part, and an annular shape provided on an outer peripheral part of the inner hub. An outer plate, and a rubber member that joins the outer peripheral wall of the inner hub and the inner peripheral wall of the outer plate,
And a fixing portion fixed to the armature, which is a portion extending in the axial direction of the outer plate.

[0006]

According to the electromagnetic clutch of the present invention, since the outer plate is fixed to the armature at the axially extending portion, the outer diameter of the outer plate can be increased and the outer diameter of the cushion rubber adhered to the inner peripheral wall of the outer plate can be increased. Therefore, the mounting strength of the cushion rubber is increased and the durability is improved. Moreover, the number of parts can be reduced by eliminating the conventional rivets.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show the configuration of a first embodiment in which the present invention is applied to an electromagnetic clutch of a car cooler compressor. In FIGS. 1 and 2, 1 is an exciting coil, 2 is a rotor, which is formed by molding an iron material that is a magnetic material into a ring shape having a U-shaped cross section. In the space surrounded by the rotor 2, a stator 3 in which the exciting coil 1 is fixed with epoxy resin or the like is arranged,
The stator 3 holds the exciting coil 1 in a fixed manner without contacting the rotor 2.

The pulley 4 is press-fitted into the rotor 2 and integrated by welding. The inner diameter portion of the rotor 2 is connected to the cylindrical protrusion 6 of the compressor housing via the bearing 5.
It is rotatably attached to. A pulley groove 7 that engages with a poly V belt (not shown) is formed on the outer diameter portion of the pulley 4. Accordingly, the pulley 4 is rotated by receiving the driving force of an automobile running engine (not shown) via the poly V belt.

The armature 9 faces the extension of the outer plate 12 in the axial direction, has a ring shape, and is made of an iron material which is a magnetic material. Three or more fixing holes 14 are provided on the circumference of the armature 9, and the fixing portions 15 of the outer plate 12 are fitted into these fixing holes 14. As a result, the armature 9 and the outer plate 12 are coupled on the axial friction surface side of the outer plate 12.

The inner hub 13 is the outer plate 12
The inner side of the inner hub 13 and the outer side of the outer plate 12 are annular cushion rubber 1 provided on the inner diameter side of the cushion rubber 1
Combined by 8. Next, the operation will be described. When a voltage is applied to the exciting coil 1, the armature 9 overcomes the reaction force of the cushion rubber 18 and moves to the right in the axial direction in FIG. 1 to be attracted to the rotor 2, and the armature 9 and the rotor 2 are connected. As a result, the power from the engine is transmitted to the pulley 4,
It is transmitted to a compressor (not shown) via the rotor 2, the armature 9, the outer plate 12, the cushion rubber 18, and the inner hub 13. At this time, the cushion rubber 18 applies a reaction force against the electromagnetic attraction force to the outer plate 1
It is given to the armature 9 via 2. Excitation coil 1
When the voltage to the armature 9 is cut off, the armature 9 moves axially left from the rotor 2 in FIG.
As a result, the power from the armature 9 to the rotor 2 is no longer transmitted.

Next, the assembling procedure will be described. Rubber is injected between the inner hub 13 and the outer plate 12 to manufacture the hub portion. The armature 9 is assembled to the manufactured hub portion, the fixing portion 15 of the outer plate 12 is bent, and the fixing portion 15 is fixed to the fixing hole 14 of the armature 4. According to the first embodiment, it is possible to eliminate the rivet that has conventionally been provided on the outer diameter side of the outer plate 12. Therefore, for example, the outer diameter 106
When an armature of mm was used, the outer diameter of the outer plate was 80.2 mm in the conventional example, but could be increased to 98.8 mm in this example. Further, when the same cushion rubber is used, the outer diameter of the armature can be reduced from the conventional 106 mm to 87.4 mm.

In the first embodiment, the outer plate 12
The armature 9 was fixed by bending and fixing. Instead of this, fixing by spot welding, projection welding or the like is also possible. In the case of these weldings, the shape accuracy of the fixing hole 14 of the above embodiment can be loosened. A second embodiment of the present invention is shown in FIG.

The second embodiment is an example in which an annular bent portion 12a is formed on the axial friction surface side of the outer plate 12, and the claw 9a of the armature 9 is caulked and fixed to the bent portion 12a. A plurality of claws 9a of the armature 9 are formed on the outermost circumference of the armature 9, and extend in the radially outer end of the armature 9 in the direction opposite to the axial friction surface, and extend in the radially inward direction from the extension. Are doing Concerning other constituent parts, constituent parts that are substantially the same as those in FIG.

According to the second embodiment, the outer diameter of the outer plate can be greatly increased by eliminating the rivet and using an armature having the same outer diameter as compared with the conventional one, and the cushion rubber of the same size. If you use, you can significantly reduce the outer diameter of the armature. For example, if the rubber dimensions are the same, the outer diameter of the armature can be reduced by about 10 mm, and the pulley diameter can be reduced by about 10 mm. Further, according to the second embodiment, if the pulley diameter is the same as that of the conventional one, the radial dimension of the cushion rubber 18 can be increased, and the rubber life can be greatly improved. For example, it has been found that increasing the radial dimension of the cushion rubber from 10 mm to 15 mm can increase the durability of the rubber 2-3 times.

According to the present invention, the claw 9 of the armature 9 is provided.
It is also possible to provide a slit in the outer plate corresponding to a. Further, as another embodiment of the present invention, the armature may be divided into an inner ring and an outer ring. In this case, the inner ring and the outer ring are separately and integrally fixed to the outer plate, or the inner ring and the outer ring are fixed to the outer plate by another method.

[0016]

As described above, according to the electromagnetic clutch of the present invention, since the outer plate and the armature are connected to each other on the axial side of the outer plate, the rivet is fixed to the outer peripheral portion of the outer plate. Since no space is required, the outer diameter of the outer plate can be increased, and therefore the inner diameter of the cushion rubber that connects the outer plate and the inner hub can be increased or the wall thickness of the cushion rubber can be increased. This has the effect of improving the durability of the clutch. Further, there is an effect that the number of parts can be reduced by eliminating rivets.

[Brief description of drawings]

FIG. 1 is a partial sectional view showing an electromagnetic clutch according to a first embodiment of the present invention.

FIG. 2 is a schematic view of the armature shown in FIG. 1 viewed in the direction of arrow A.

FIG. 3 is a partial sectional view showing an electromagnetic clutch according to a second embodiment of the present invention.

[Explanation of symbols]

 1 Excitation Coil 2 Rotor 4 Pulley 9 Armature 12 Outer Plate 12a Bent Part (Fixed Part) 13 Inner Hub 14 Fixing Hole 15 Fixed Part 18 Action Rubber (Rubber Member)

Claims (1)

[Claims] 1. A rotor rotatably supported by a housing and rotated by receiving a rotational force from a drive unit, an armature facing the rotor and capable of coming into contact with and separating from the rotor; An exciting coil for attracting the armature to the rotor, an inner hub for transmitting a rotational force to a driven part, an annular outer plate provided on an outer peripheral portion of the inner hub, an outer peripheral wall of the inner hub and an inner peripheral wall of the outer plate. An electromagnetic clutch comprising: a rubber member for connecting the armature and a fixing portion that is a portion that extends in the axial direction of the outer plate and that is fixed to the armature.