JP2000230576A - Electromagnetic clutch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a design appropriate for relieving a shock at sucking of an armature and to sufficiently reduce an operation sound at the time of suction of the armature. SOLUTION: A friction plate 4 comprising a magnetic substance and disposed in opposed to an armature 8 is retained by a retaining member (flat spring) 40, so as to be displaceable in an axial direction of a rotating member 1. The friction plate 4 is projected by a predetermined quantity δ to the armature 8 side from the rotation member 1 at non-energizing of an electromagnetic coil 2. According to this, a shock at suction of the armature 8 is relieved by a shock-absorbing function due to a resilient deformation of the flat spring 40 at the time of suction of the armature 8, and operation sound is reduced. Since the flat spring 40 is a special-use member for obtaining the shock- absorbing function, it is possible that a quality, a dimension, a shape and the like thereof are designed so as to obtain a resilient force appropriate for the shock-absorbing function. Thereby, the operation sound can be further reduced in comparison with conventional ones.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic clutch for intermittently transmitting power, and more particularly to a reduction in operating noise when an armature is sucked, which is suitable for driving a compressor of a refrigerating cycle of an air conditioner for an automobile. .

[0002]

2. Description of the Related Art A conventional electromagnetic clutch includes a rotor driven to rotate, an armature opposed to the rotor,
An electromagnetic coil that generates an electromagnetic attractive force, the armature is attracted to the rotor by the electromagnetic attractive force of the electromagnetic coil,
It is designed to transmit power.

[0003] Further, there is also a type in which a friction material is assembled on a friction surface of a rotor. This friction material is obtained by mixing metal powder, graphite, or the like with a fiber as a base material and heating and molding with a binder. And thus are used to improve transmission torque. And patent 2808
The electromagnetic clutch described in Japanese Patent Application Laid-Open No. 895-895 has a friction material assembled as described above, in which a small amount of the friction material protrudes from the friction surface of the rotor toward the armature, so that the armature is first applied to the friction material during the suction of the armature. By using the elastic deformation of the friction material, the shock at the time of armature suction is reduced, and the operation noise is reduced.

[0004]

However, since the original purpose of using the friction material is to improve the transmission torque, a friction material having a high friction coefficient is selected, and the size and shape of the friction material are also transmitted. Determined in relation to torque. Due to such restrictions, the material, size, shape, etc. of the friction material,
It is difficult to optimize the armature suction to reduce the impact. Therefore, in the above publication,
There has been a problem that the operation sound at the time of armature suction cannot be sufficiently reduced.

[0005] The present invention has been made in view of the above points,
An object of the present invention is to enable a design suitable for reducing an impact at the time of armature suction, and to sufficiently reduce an operation sound at the time of armature suction.

[0006]

In order to achieve the above object, according to the first to fifth aspects of the present invention, when the electromagnetic coil (2) is not energized, the electromagnetic coil (2) projects toward the armature (8) from the rotating member (1). A friction plate (4) made of a magnetic material,
An elastic holding member (40, 50) for holding the friction plate (4) on the rotating member (1) so as to be displaceable in the axial direction is provided.

According to this, at the time of armature suction, the armature (8) hits the friction plate (4) before hitting the rotating member (1), and the armature and the friction plate (4) are elastically deformed by the holding members (40, 50). Rotating member (1)
And the shock at the time of armature suction is reduced by the buffering action of the elastic deformation of the holding members (40, 50). Therefore, the operation sound at the time of armature suction can be reduced.

Further, since the holding members (40, 50) are dedicated members for obtaining the above-mentioned buffering action, their materials, dimensions, shapes and the like are designed so as to obtain an elastic force suitable for the buffering action. Therefore, the operation noise can be reduced more effectively than before. Also,
According to the second aspect of the present invention, the rotating member (1) includes an inner cylindrical portion (1b), an outer cylindrical portion (1c), and an annular concave portion formed between the two cylindrical portions (1b, 1c). (1d), the opening of the recess (1d) is opposed to the armature (8), and the electromagnetic coil (2), the friction plate (4) and the holding member ( 40, 5
0) is arranged.

[0009] According to this, friction for damping is provided by utilizing the space in the annular recess (1d) in the electromagnetic clutch of the type in which the rotating member (1) and the electromagnetic coil (2) rotate integrally. Plate (4) and holding member (40, 5
Since the arrangement of (0) is arranged, it can be carried out without increasing the size of the electromagnetic clutch. The holding member may be a metal leaf spring (40) as described in claim 3, or may be formed of an elastomer as in claim 4.

Further, the invention according to claim 5 is characterized in that the electromagnetic coil (2) is fixed to the rotating member (1) by a holding member (50) made of an elastomer. According to this, since both the electromagnetic coil (2) and the friction plate (4) are held and fixed by the holding member (50), the number of assembly steps and the number of parts can be reduced. In the invention according to the sixth aspect, the holding member (5) made of an elastomer is disposed on the rotating member (1) at a position facing the armature (8).
0), and the holding member (50) is projected to the armature (8) side of the rotating member (1) when the electromagnetic coil (2) is not energized.

According to this, at the time of armature suction, the armature (8) hits the holding member (50) before hitting the rotating member (1). At that time, the shock at the time of armature suction is generated by the buffering action due to the elastic deformation of the holding member (50). Be relaxed. Therefore, the operation sound at the time of armature suction can be reduced. In addition, the material and the like of the holding member (50) can be selected so that an elastic force suitable for the buffering action can be obtained, so that the operation noise can be more effectively reduced than before.

Further, the holding member (50) is a friction plate (4).
Since the setting is softer than that, the sound when the armature (8) hits the holding member (50) can also be reduced. In addition, the code | symbol in the parenthesis of each said means shows the correspondence with the concrete means of embodiment mentioned later.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) An embodiment of the present invention will be described below with reference to the drawings. 1 to 6 show a first embodiment of the present invention, in which 1 is a driving-side rotor,
A pulley portion 1a having a multiple V-groove into which the multiple V-belt is engaged is provided integrally with the outer peripheral portion. The drive-side rotor 1 is a drive-side rotating member that rotates by receiving torque from an automobile engine via a belt (not shown), and is made of an iron-based metal (ferromagnetic material) such as low carbon steel and has a U-shaped cross section. 2
It is shaped into a heavy ring.

An annular concave portion 1d is formed between the inner cylindrical portion 1b and the outer cylindrical portion 1c of the drive-side rotor 1, and a radial side surface of the rotor 1, that is, the inner cylindrical portion 1b. And a friction surface 1 on the axial end of the outer cylindrical portion 1c.
e is formed. Reference numeral 2 denotes an electromagnetic coil for generating an electromagnetic attraction force, which is provided in the recess 1 d of the driving-side rotor 1. The electromagnetic coil 2 is insulated and fixed to the recess 1d by a resin member 3 formed in the recess 1d while being wound on a resin winding frame 2a. Therefore, the electromagnetic coil 2 rotates integrally with the drive-side rotor 1.

Reference numeral 4 denotes a flat ring-shaped friction plate made of an iron-based metal (ferromagnetic material) such as low-carbon steel, which is disposed in the recess 1d of the driving-side rotor 1 on the opening side of the recess 1d. ing. The friction plate 4 is held by a leaf spring (holding member) 40 spot-welded to the friction plate 4 so as to be displaceable in the axial direction (the left-right direction in FIG. 1). The leaf spring 40 is made of a spring material such as stainless steel (non-magnetic material). As shown in FIG. 4, a plurality of (three in this example) protrusions 40b are integrally formed at equal intervals on the outer peripheral side of the ring-shaped main body 40a. Molding. The plurality of protrusions 40b are inserted into and supported by the annular groove 1f (see FIGS. 1, 2, and 3) of the outer peripheral cylindrical portion 1c of the rotor 1.
The projection 40b is fixed to the outer cylindrical portion 1c of the rotor 1 by welding or other means.

FIG. 3 shows a state in which the friction plate 4 and the leaf spring 40 are assembled to the rotor 1. After the electromagnetic coil 2 is insulated and fixed in the recess 1d of the rotor 1 by the resin member 3, it is integrated in advance. The friction plate 4 and the leaf spring 40 are assembled to the rotor 1. Then, as shown in FIG. 2, the protrusion 40 b abuts on the side wall surface of the annular groove 1 f to position the friction plate 4 and the leaf spring 40 in the axial direction.
Further, as shown in FIGS. 2 and 3, the outer peripheral end of the protrusion 40b abuts on the outer peripheral wall of the annular groove 1f, thereby positioning the friction plate 4 and the leaf spring 40 in the radial direction. Since there is no particular need to position the friction plate 4 and the leaf spring 40 in the circumferential direction, no circumferential positioning means is provided.

Here, as shown in FIG.
When the electric current is not supplied, the friction surface 4a of the friction plate 4 is moved by a predetermined amount δ toward the armature (described in detail later) 8 from the friction surface 1e of the rotor 1.
The axial direction of the friction plate 4 is set so as to protrude (for example, 0.01 to 0.20 mm). Reference numeral 5 denotes a compressor as a driven device (rotary machine), and reference numeral 6 denotes a front housing of the compressor 5 located on the electromagnetic clutch side. The front housing 6 is made of an aluminum-based metal, and has a boss 6a that projects cylindrically outward in the axial direction.
Is integrally molded at the center. Here, the compressor 5 is for compressing a refrigerant in a refrigeration cycle of an air conditioner for a vehicle, and may be any type such as a known swash plate type, a vane type, and a scroll type.

Reference numeral 7 denotes a bearing for rotatably supporting the drive-side rotor 1 on a boss 6a of the front housing 6. In this embodiment, the bearing 7 includes an outer ring 7a fixed to the inner peripheral surface of the drive-side rotor 1. Inner ring 7 fixed to the outer peripheral surface of boss 6a
and a ball bearing 7b rotatably held between the two 7a and 7b.

Reference numeral 8 denotes a friction surface 1e of the rotor 1 and a friction plate 4
The armature is opposed to the armature, and is formed of a ferrous metal (ferromagnetic material) such as low carbon steel in a ring-shaped flat plate shape. When the electromagnetic coil 2 is not energized, the armature 8 is placed at a position (a position shown in FIGS. 1 and 2) at a predetermined minute distance from the friction surface 1e of the rotor 1 and the friction surface 4a of the friction plate 4 (elastic connecting member). 9 is held by the spring force. The leaf springs 9 are in the form of elongated thin plates, and are arranged in plural numbers in the circumferential direction of the armature 8. One end of each leaf spring 9 is connected to the armature 8 by a rivet (not shown). The end is a hub 1 with rivets 10
Connected to 1.

Here, in the radial direction of the armature 8,
A plurality of arc-shaped grooves 8a extending in the circumferential direction are formed as magnetic shielding portions in a portion opposed to the middle of the friction plate 4, and the magnetic circuit B of the electromagnetic coil 2 is formed by forming the grooves 8a in FIG. 2, the armature 8 is bent between the friction plate 4 and the radially intermediate portion of the armature 8. The hub 11 is formed of a ferrous metal into a shape having a disk portion 11a extending in the radial direction and a central cylindrical portion 11b, and a stopper member 12 made of an elastic material such as rubber is provided on the outer peripheral side of the disk portion 11a. The stopper member 12 defines the axial position of the armature 8 (position when the coil is not energized).

The center cylindrical portion 11b of the hub 11 is
And is fitted to the rotating shaft 13 by a spline connection or the like. Then, a bolt 14 is screwed into a screw hole at the tip of the rotating shaft 13 so that the inner peripheral flange 11 of the hub 11 is rotated.
The hub 11 is integrally connected to the rotating shaft 13 by sandwiching c between the stepped portion of the rotating shaft 13. Next, the configuration of the current path to the electromagnetic coil 2 that rotates together with the rotor 1 will be described. In this current path configuration, slip rings 19, 20 and brushes are provided on the inner peripheral side of the compressor boss 6a supporting the bearing 7. 22 and 23 are provided.

The layout of the sliding energizing mechanism is specifically configured as follows. On the inner peripheral side of the electromagnetic coil 2 in the inner peripheral cylindrical portion 1b of the rotor 1, grooves 1h and 1i are formed in a portion on the armature 8 side, and a positive electrode side electrically connected to both ends of the electromagnetic coil 2; The two lead wires 16 and 17 on the negative electrode side are spaced at a predetermined interval, and the inside of the groove portions 1h and 1i is wired in the inner circumferential direction while securing electrical insulation between them.
1 and 2 show only one of the two lead wires 16 and 17 for simplification of the drawing. In this example, the lead wires 16 and 17 are bare wires exposing a conductive metal such as copper or aluminum.

On the inner peripheral side of the friction plate 4 and the armature 8, a ring-shaped holding plate 18 made of an electric insulating material such as resin is disposed. The holding plate 18 is integrated with the inner peripheral portion of the rotor 1 by fitting and locking the projection 18a into a concave portion 1k provided in the inner peripheral protruding end 1j of the inner peripheral cylindrical portion 1b of the rotor 1. , And rotates with the rotor 1 at one end.

On the inner peripheral side of the holding plate 18, two positive and negative slip rings 19, 20 are fixed concentrically to the boss 6 a side. As shown in FIG. 5, the inner peripheral portions of the lead wires 16 and 17 are formed so as to be embedded inside the thickness of the holding plate 18.
Are connected to the positive and negative slip rings 19 and 20, respectively.

On the other hand, a cylindrical space 21 is secured between the central cylindrical portion 11b of the hub 11 fixed to the rotating shaft 13 of the compressor 5 and the inner peripheral surface of the boss portion 6a. 2
1, brushes 22 and 23 on the positive electrode side and the negative electrode side are arranged. The brushes 22 and 23 have a cylindrical shape, and ring-shaped holding members 24 and 25 formed of an electric insulating material such as a resin are arranged at both ends in the axial direction.

The two holding members 24 and 25 maintain a predetermined radial distance between the cylindrical brushes 22 and 23 to achieve electrical insulation. The outer peripheral extension of the holding member 25 ensures electrical insulation between the outer brush 22 and the inner peripheral surface of the boss 6a. One holding member 24 is the holding plate 1
8 can be integrally formed, but the separate plate
8 may be fixed.

Further, a cylindrical holding member 26 extending from the inner peripheral portion of the inner brush 23 to the compressor 5 side is disposed in the space 21, and this holding member 26 is also formed of an electrically insulating material such as resin. As shown in FIG. 6, a plurality of projections 26b are formed on the outer periphery of the flange 26a of the holding member 26, and these projections 26b are fitted and locked in recesses 6b provided on the inner peripheral surface of the boss 6a. By doing so, the holding member 26 is held on the inner peripheral portion of the boss 6a.

The inner peripheral surface of the holding member 26 and the hub 1
The holding member 26 is fixed to the boss portion 6a side while maintaining a predetermined interval between the holding member 26 and the outer peripheral surface of the central cylindrical portion 11b. The holding member 25 described above is held between the outer peripheral surface of the holding member 26 and the inner peripheral surface of the boss 6a. A coil spring 27 is disposed between the holding member 25 and the flange 26a of the holding member 26 as an elastic pressing member for the brushes 22, 23, and the springs of the coil spring 27 apply the brushes 22, 23 to the slip ring 19. , 20 are elastically pressed into contact with each other. One ends of the two lead wires 28 and 29 on the positive electrode side and the negative electrode side penetrate the holding member 25 and are electrically connected to the brushes 22 and 23. Only one of these two lead wires 28 and 29 is shown for simplicity of illustration.

The two lead wires 28 and 29 are formed by covering the periphery of the conductor with an insulating coating, and the other ends thereof are exposed to the outside of the flange 26a through the flange 26a of the holding member 26. I have. Of the two lead wires 28 and 29, bent portions 28a and 29a having a spring action are formed at the exposed ends. Reference numeral 30 denotes a resin connector body which is molded and fixed on the outer surface of the front housing 6 and has two thin flat connection terminals 31 made of conductive metal inside the connector body 30. , 32 are provided at predetermined intervals so as to extend outward in the radial direction of the front housing 6. Only one connection terminal 31, 32 is shown for simplicity of illustration.

The connection terminals 31 and 32 are connected to the holding member 2.
The flat plate portions 31a and 32a are arranged on the surface facing the flange portion 26a of No. 6, and the lead wires 28 and
The electrical connection between the lead wires 28, 29 and the connection terminals 31, 32 is obtained by elastically pressing the bent portions 28a, 29a of the 29. The lead wire 16 described above,
17, slip rings 19, 20, brushes 22, 23,
By the lead wires 28 and 29 and the connection terminals 31 and 32,
The current path of the electromagnetic coil 2 is configured. Connector body 3
The 0 connection terminals 31 and 32 are electrically connected to an external control circuit (not shown) for controlling the on / off operation of the electromagnetic clutch (that is, the on / off operation of the compressor 5).

Next, the operation of the above configuration will be described.
Since the rotor 1 is rotatably supported on the outer peripheral surface of the boss 6a of the front housing 6 by the bearing 7,
When an automobile engine (not shown) is operated, the rotation of the crank pulley of the engine is transmitted to the pulley 1a via a belt (not shown), and the rotor 1, the electromagnetic coil 2, the friction plate 4, and the leaf spring 40 constantly rotate. .

As the rotor 1 and the like rotate, the lead wire 1
6, 17, the holding plate 18, the holding member 24 and the slip rings 19, 20 rotate together. On the other hand, brushes 22, 23, holding members 25, 26, coil spring 2
7, and the lead wires 28 and 29 are all held and fixed on the boss 6a side. Therefore, one end faces in the axial direction of the brushes 22 and 23 are pressed against the rotating slip rings 19 and 20 by the spring force of the coil spring 27 and slide.

In the above state, when the voltage of the vehicle-mounted power supply is applied to the connection terminals 31 and 32 of the connector body 30 from the external control circuit to operate the compressor 5, the above members (16, 17, 19, 20, 22, 23, 28, 2
The electromagnetic coil 2 is energized through an energizing path constituted by 9). Then, a magnetic flux flows in a magnetic circuit B (see FIGS. 1 and 2) formed between the rotor 1 and the armature 8, and thereby, the friction surface 1e of the rotor 1 and the friction surface 4a of the friction plate 4 and the armature 8 , An electromagnetic attraction force is generated between the armature 8 and the armature 8.
Of the rotor 1 and the friction surface 4a of the friction plate 4 against the leftward force of the rotor 1).

At this time, the armature 8 first contacts the friction surface 4a of the friction plate 4, and the armature 8 and the friction plate 4 are displaced rightward in FIG. The shock at the time of suction of the armature 8 is reduced by the buffering action due to the deformation, and the operating noise is reduced. Moreover, since the leaf spring 40 is a dedicated member for obtaining the above-described buffering action, it is easy to design its material, dimensions, shape, and the like so as to obtain an elastic force suitable for the buffering action. As a result, the operation noise can be more effectively reduced than before.

Then, the armature 8 is attracted to the friction surface 1e of the rotor 1 and the friction surface 4a of the friction plate 4, and as a result, the rotor 1 and the armature 8 rotate integrally. It rotates integrally with the hub 11 via the rivet 10. Therefore, the rotation of the rotor 1 is transmitted to the rotating shaft 13 of the compressor 5 via the hub 11,
The compressor 5 operates.

On the other hand, when stopping the compressor 5, the power supply to the electromagnetic coil 2 is cut off. As a result, the electromagnetic attraction force disappears, so that the armature 8 is separated from the friction surface 1e of the rotor 1 and the friction plate 4 by the axial elastic force of the leaf spring 9, and the rotation transmission to the rotary shaft 13 of the compressor 5 is interrupted. Therefore, the compressor 5 stops. The friction plate 4 is a leaf spring 4
Due to the elastic force of 0, the rotor 1 is returned to a position projecting a predetermined amount δ from the rotor 1 as shown in FIGS.

In the present embodiment, since the friction plate 4 and the leaf spring 40 for performing the buffering action are arranged by utilizing the space in the annular concave portion 1d, the electromagnetic clutch can be implemented without increasing the size. can do. In the above embodiment, a soft rubber or the like may be arranged between the resin member 3 and the leaf spring 40, and the rubber or the like and the leaf spring 40 may perform a buffering action.

(Second Embodiment) FIG. 7 shows a second embodiment. In the above embodiment, the friction plate 4 is held by a leaf spring 40, whereas in this embodiment, a rubber-based elastomer is used. The friction plate 4 is held on the rotor 1 by the holding member 50. The holding member 50 is made of an elastic resin (for example, nylon 6) having excellent electrical insulation, heat resistance, and wear resistance.
6) Or made of rubber, holding the friction plate 4 and insulatingly fixing the electromagnetic coil 2 to the rotor 1, thereby reducing the number of assembly steps and the number of parts.

When the electromagnetic coil 2 is not energized, the friction surface 4a of the friction plate 4 is moved a predetermined amount δ (for example, 0.01 to 0.20 m) closer to the armature 8 than the friction surface 1e of the rotor 1.
m) The friction plate 4 is axially positioned so as to project. Since the leaf spring 40 is not used, the annular groove 1f of the outer peripheral cylindrical portion 1c of the rotor 1 is omitted.

When the electromagnetic coil 2 is energized, the armature 8 is attracted to the rotor 1 and the friction plate 4 side. At this time, the armature 8 first strikes the friction surface 4a of the friction plate 4 and elastically deforms the holding member 50. While the armature 8 and the friction plate 4 are displaced rightward in FIG. 7, the shock at the time of suction of the armature 8 is reduced by the buffering action due to the elastic deformation of the holding member 50, and the operating noise is reduced.

Moreover, since the holding member 50 is a dedicated member for obtaining the above-mentioned buffering action, its material and characteristics can be selected so that an elastic force suitable for the buffering action can be obtained. Thereby, the operation noise can be reduced more effectively than in the past. Further, since the friction plate 4 and the holding member 50 for performing the buffering action are arranged by utilizing the space in the annular concave portion 1d, it is possible to carry out without increasing the size of the electromagnetic clutch.

(Third Embodiment) FIG. 8 shows a third embodiment. In the second embodiment, the friction surface 4a of the friction plate 4 is used.
Is made to protrude from the friction surface 1 e of the rotor 1, whereas in the present embodiment, the grease member 50 is connected to the friction surface 1 e of the rotor 1.
a predetermined amount δ (e.g., 0.01 to
0.20 mm).

When the electromagnetic coil 2 is energized, the armature 8 is attracted to the rotor 1 and the friction plate 4 side. At this time, the armature 8 first hits the holding member 50, and the armature 8 is elastically deformed. 8 is rotor 1
8 until it comes into contact with the friction surface 1e of the friction plate 4 and the friction surface 4a of the friction plate 4. The shock at the time of suction of the armature 8 is reduced by the buffering action due to the elastic deformation of the holding member 50, and the operating noise is reduced. .

Moreover, since the holding member 50 is softer than the friction plate 4, the sound when the armature 8 hits the holding member 50 can be reduced. Further, since the holding member 50 is a dedicated member for obtaining the above-described buffering action, its material, characteristics, and the like can be selected so that an elastic force suitable for the buffering action can be obtained. Can be more effectively reduced than before.

Further, since the holding member 50 for performing the buffering action is disposed by utilizing the space in the annular concave portion 1d, the present invention can be carried out without increasing the size of the electromagnetic clutch. (Other Embodiments) In the above embodiment, the example in which the pulley portion 1a is formed integrally with the rotor 1 has been described, but the pulley portion 1a formed separately may be integrally joined to the rotor 1.

Further, the specific configuration of the current supply path to the electromagnetic coil 2 is not limited to the illustrated one, but can be variously changed according to the specifications of the electromagnetic clutch. Further, in the above-described embodiment, the example in which the present invention is applied to the coil rotation type electromagnetic clutch in which the rotor 1 and the electromagnetic coil 2 rotate integrally has been described. ,
The present invention is applicable.

In each of the above embodiments, the drive-side rotor (drive-side rotating member) 1 integrated with the pulley portion 1a is provided.
The present invention is applied to a coil rotation type electromagnetic clutch of a type in which the electromagnetic coil 2 is disposed on the rotating shaft 13 of a compressor (rotating machine) 5 as another type of coil rotation type electromagnetic clutch. The electromagnetic coil 2 is arranged on the hub (driven-side rotating member) 11 side, and the armature 8 is connected to the driving-side rotor 1 via a leaf spring (elastic connecting member) 9 to reduce the electromagnetic attraction of the electromagnetic coil 2. A type in which the rotation of the driving rotor 1 is transmitted to the rotating shaft 13 via the armature 8 and the hub 11 by adsorbing the armature 8 to the hub 11 by means of an electromagnetic clutch is known. The present invention can also be applied.

[Brief description of the drawings]

FIG. 1 is a half cross-sectional view of an electromagnetic clutch according to a first embodiment of the present invention, and shows an AA cross section of FIG.

FIG. 2 is a half cross-sectional view of the electromagnetic clutch according to the first embodiment of the present invention, showing a cross section taken along line CC of FIG. 3;

FIG. 3 is a front view of a rotor portion of the electromagnetic clutch of FIGS.

FIG. 4 is a front view of a leaf spring of the electromagnetic clutch of FIGS.

FIG. 5 is a sectional view taken along the line JJ of FIG. 3;

FIG. 6 is a cross-sectional view showing an arrangement of a boss portion and a cylindrical holding member in the electromagnetic clutch of FIGS.

FIG. 7 is a half sectional view of an electromagnetic clutch showing a second embodiment of the present invention.

FIG. 8 is a half sectional view of an electromagnetic clutch showing a third embodiment of the present invention.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 rotor (rotating member), 2 electromagnetic coil, 4 friction plate, 8 armature, 40 leaf spring (holding member), 50
... holding member.

Claims (6)

[Claims] 1. A rotating member (1) made of a magnetic material, an electromagnetic coil (2) that generates an electromagnetic attraction force when energized, and a rotating member (1) The rotating member (1) generated by the electromagnetic attraction force
And an armature (8) made of a magnetic material, which is attracted to the armature (8). A friction plate (4) made of a magnetic material disposed; and an elastic holding member (40, 50) for holding the friction plate (4) on the rotating member (1) so as to be axially displaceable.
And an electromagnetic clutch comprising: 2. The rotating member (1) has an inner peripheral cylindrical portion (1).
b), an outer peripheral cylindrical portion (1c), and both cylindrical portions (1b,
1c) is formed in a sectional shape having an annular recess (1d) formed between the recesses (1d), and the opening of the recess (1d) faces the armature (8). The electromagnetic clutch according to claim 1, wherein an electromagnetic coil (2), the friction plate (4), and the holding members (40, 50) are arranged. 3. The holding member is a leaf spring made of metal.
The electromagnetic clutch according to claim 1, wherein: 4. The electromagnetic clutch according to claim 1, wherein the holding member is made of an elastomer. 5. The holding member (50) is made of an elastomer, and the holding member (50) fixes the electromagnetic coil (2) to the rotating member (1). Electromagnetic clutch as described. 6. A rotating member (1) made of a magnetic material, an electromagnetic coil (2) for generating an electromagnetic attraction force when energized, and a rotating member (1) The rotating member (1) generated by the electromagnetic attraction force
An armature (8) made of a magnetic material that is attracted to the armature (8), wherein the holding member (5) made of an elastomer is disposed on the rotating member (1) at a position facing the armature (8).
0), wherein the holding member (50) is made to protrude more toward the armature (8) than the rotating member (1) when the electromagnetic coil (2) is not energized.