JP2000320575A - Electromagnetic connection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce attraction sound of an armature, prevent wrong operation of the armature and improve the durability of a damper rubber. SOLUTION: A damper rubber 15 is stored in a damper rubber storing part 16 provided on the flange 10 of an armature hub 11. At least the inside of the outer periphery edge of the head 18b of a pin 18 with head penetrated a pin main body 18a in the insertion hole 24 of the damper rubber is formed into an arc-shape part 40. A cylindrical projection 25 is integrally provided on the opening edge of the insertion hole of the damper rubber. A surface 41 which retreats in the axial direction, going toward the outside is formed on the diametrical direction outside of the surface which faces the head of the damper rubber.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a damper rubber type electromagnetic coupling device used as, for example, an electromagnetic clutch for a car air conditioner, and more particularly, to prevent the generation of an attraction sound by reducing an impact when an armature magnetically attracts to a rotor. The present invention relates to an electromagnetic coupling device using a so-called non-adhesion type damper rubber in which a damper rubber is attached to an armature hub in an unbonded state.

[0002]

2. Description of the Related Art For example, an electromagnetic clutch mounted on a compressor for a car air conditioner employs a structure in which an armature is supported by an armature hub mounted on a rotating shaft of the compressor via a leaf spring or damper rubber or both members. The damper rubber alleviates the impact when the armature is magnetically attracted to the rotor, thereby preventing the generation of an attraction sound.

Recently, there have been many types of electromagnetic clutches of this type using a damper rubber system using a damper rubber. Such a damper rubber type electromagnetic clutch is disclosed, for example, in Japanese Utility Model Registration No. 2533764, and Japanese Patent Application Laid-Open No. 10-23.
No. 53, an adhesive type in which a damper rubber is fixed to a rivet fixed to an armature is disclosed in, for example, Japanese Utility Model Publication No. 58-8997, and Japanese Unexamined Patent Publication No. 9-2100.
As shown in Japanese Patent Publication No. 95, it is classified into an adhesiveless type in which a damper rubber is pressed into a headed pin and held.

FIG. 4 of Japanese Patent Application Laid-Open No. 9-210095 discloses a stopper plate fixed with rivets to a flange portion of an armature hub, and an insertion hole formed in the stopper plate. A cup-shaped damper cover fixed to the part, a damper rubber pressed into the inside of the damper cover, and a headed pin fixed to the armature by a caulked portion at the tip of the pin body while being pressed into an insertion hole formed in the center of the damper rubber. A provided structure is disclosed.

[0005] A cylindrical projection is formed on the end face of the damper rubber on the side opposite to the armature, and the tip of the pin body of the headed pin is caulked while the armature is in contact with the stopper plate. The inner surface of the head of the pin is in contact with the end surface of the cylindrical projection of the damper rubber.
In addition, a gap having a size smaller than the size of an air gap formed between the armature and the rotor is formed between the head of the headed pin and an end surface other than the cylindrical protrusion of the damper rubber.

In the electromagnetic clutch having such a structure, the armature is magnetically attracted to the rotor against the elasticity of the damper rubber. After the cylindrical protrusion of the damper rubber is compressed, the damper rubber is compressed by the entire inner surface of the head of the headed pin. Therefore, just before the armature is magnetically attracted to the rotor, the elastic restoring force of the damper rubber is increased, so that the impact when the armature is magnetically attracted to the rotor is reduced, and a striking sound between metal members called so-called armature attracting sound is generated. Is prevented.

[0007]

In the above-described electromagnetic clutch, the load acting on the damper rubber increases until the rotation of the rotor (drive side) and the rotation of the rotary shaft of the compressor (driven side) are completely synchronized. At the same time, when the rotation of the rotor and the rotation shaft are completely synchronized, the load acting on the damper rubber is reduced. Further, the load acting on the damper rubber changes due to the rotation fluctuation of the rotor and the rotation fluctuation of the rotating shaft due to the fluctuation of the load of the compressor.

In other words, the axis of the headed pin is shifted with respect to the axis of the damper cover in a state where the damper rubber is compressed in the axial direction and elastically deformed. The end face of the damper rubber is rubbed at the corner. When such a phenomenon is repeated, the end face of the damper rubber becomes rough, and cracks are easily generated in the damper rubber, and there is a problem that durability is reduced.

To improve the durability of such a damper rubber, Japanese Patent Application Laid-Open No. Hei 7-332393 discloses a structure as shown in FIG.
And the structure described in paragraph [0037] have been proposed.
In this conventional electromagnetic clutch, when the armature is magnetically attracted to the rotor, the outer peripheral edge portion of the head and the end surface of the damper rubber are arranged so that the inner corner of the outer periphery of the headed pin does not contact the end surface of the damper rubber. The damper rubber is formed in a shape provided with a cylindrical projection between which a gap having a dimension equal to or larger than an air gap can be formed.

However, according to such a structure, the operation and effect obtained by using the damper rubber having the shape shown in FIG. 4 of JP-A-9-210095 cannot be obtained.
Armature suction noise cannot be reduced. In addition, simply increasing the elastic restoring force of the damper rubber results in a malfunction of the armature in which the attraction force of the armature is relatively reduced by the magnetic flux of the electromagnetic coil.

Further, unless the above-described structure is employed in which the end surface of the damper rubber is pressed by the entire inner surface of the head of the headed pin immediately before the armature is magnetically attracted to the rotor, the function of absorbing the vibration of the armature is reduced and the armature is reduced. The suction sound cannot be reduced. To prevent this, the contact area between the above-described damper rubber and the inner surface of the head of the headed pin may be increased, but this may increase the size of the damper device portion, which may lead to an increase in the size of the entire electromagnetic clutch. is there.

That is, the above-mentioned Japanese Patent Application Laid-Open No. 7-33239
In the conventional electromagnetic clutch using the damper rubber shown in FIG. 10 of Japanese Patent Publication No. 3 (1993), a gap larger than the air gap is designed between the corner inside the outer periphery of the head of the headed pin and the escape portion of the damper rubber. It was merely provided, and the size of the damper device could not be reduced even if the durability of the damper rubber was improved, and the armature suction noise could not be reduced to a satisfactory level.

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and alleviates the impact when the armature is magnetically attracted to the rotor, thereby reducing the armature suction noise and rubbing the end face of the damper rubber. It is possible to prevent the occurrence of cracks in the rubber of the damper and to prevent malfunction of the armature (for example, a longer suction time for magnetically attracting the armature to the rotor, an operation of separating the armature from the rotor). It is an object of the present invention to obtain an electromagnetic coupling device that does not cause the problem of becoming slow.

[0014]

In order to meet this object, an electromagnetic coupling device according to a first aspect of the present invention comprises an armature hub mounted on a rotating shaft, and a damper rubber provided on a flange portion of the armature hub. A damper rubber that is housed in the housing from one side and has an insertion hole through which the pin body of the headed pin penetrates, and the flange portion fixed by a caulking portion at the tip of the pin body that passes through the damper rubber and the flange portion of the armature hub; In an electromagnetic coupling device including an armature that moves forward and backward in the axial direction on the other side surface, and an excitation device that magnetically attracts the armature against the elasticity of the damper rubber, an outer peripheral edge of a head of the headed pin is provided. At least the inside is formed in an arc shape, and a cylindrical projection is integrally provided on the opening edge of the insertion hole of the damper rubber, and the cylindrical projection is opposed to the head. Characterized in that the formation of the surface to be retracted in the axial direction in accordance yuku outwardly radially outer portion of that surface.

According to a second aspect of the present invention, in the electromagnetic coupling device according to the first aspect, the surface of the damper rubber that retreats in the axial direction faces the arc-shaped portion of the outer peripheral edge of the head of the headed pin. It is characterized in that it is formed in one of a tapered surface and a curved surface whose height gradually decreases from the portion toward the outside in the radial direction.

According to the present invention, even when the damper rubber is compressed and elastically deformed by the head of the headed pin when the armature is magnetically attracted, the amount of swelling of the portion abutting the arc-shaped portion inside the outer peripheral edge of the head is reduced. Few. Further, even if the damper rubber is raised, it comes into contact with the arc-shaped portion on the outer peripheral edge of the head of the headed pin.

That is, according to the present invention, the damper rubber is elastically deformed by being pressed by the inner side surface of the head of the headed pin. Since there is little swelling of the damper rubber in the outer portion, the end face of the damper rubber does not come into contact with the outer peripheral edge of the head. Further, even if the swelling is slightly increased, the hit is small because the inside of the outer peripheral edge of the head escapes as an arc-shaped portion.

[0018]

1 to 3 show one embodiment of an electromagnetic clutch to which an electromagnetic coupling device according to the present invention is applied. In these figures, reference numeral 1 denotes an electromagnetic clutch. The electromagnetic clutch 1 includes an armature assembly 4 mounted on a rotating shaft 3 of a compressor 2 for a car air conditioner and a cylinder formed on a housing 5 of the compressor 2. A rotor 7 rotatably supported by a portion 5a via a bearing 6 and an excitation device 8 fixed to the housing 5 are provided.

The armature assembly 4 has an armature hub 11 which is serrated and connected to the shaft end of the rotating shaft 3 of the compressor 2 and is fixed together with a stopper plate 10 by bolts 9. Stopper plate 1
Reference numeral 0 denotes a flange portion of the armature hub 11 by being fixed to the disk portion 11a of the armature hub 11 with a plurality of rivets 12.

The shape of the stopper plate 10 as viewed from the front is substantially triangular, and through holes 13 are formed near each corner. This stopper plate 10
It may be formed integrally with the disk portion 11a of the armature hub 11. That is, the flange portion of the armature hub 11 is a flange portion formed of the disk portion 11a of the armature hub 11 extending in the radial direction, or the disk portion 11a of the armature hub 11 and fixed to the disk portion 11a. Any of the flange portions formed by the stopper plate 10 may be used. A shim (not shown) for adjusting an air gap G described later is interposed between the inner surface of the stopper plate 10 and the shaft end surface of the rotating shaft 3.

In FIG. 1 and FIG.
A cup-shaped damper cover 16 forming a rubber accommodating portion of a damper rubber 15 is fixed to a position corresponding to each of the through holes 13 by welding or the like on the front side of the stopper plate 10 constituting the first flange portion. . The damper cover 16 has a through-hole 17 communicating with the through-hole 13 at the bottom 16a. A torque transmission pin 18, which is a headed pin, is inserted through the through-hole 17 and the damper rubber 15 is press-fitted. .

The pin body 18a of the torque transmitting pin 18
Is inserted into the stepped hole 23 of the armature 22 through the through hole 13 of the stopper plate 10 and fixed by caulking. The damper cover 16 may be formed integrally with the stopper plate 10 by integral molding of an aluminum alloy or a synthetic resin material.

2 (a) and 2 (b), the damper rubber 15 is formed in a cylindrical shape from synthetic rubber having excellent vibration absorbing properties, so that the torque transmitting pin 1 is located on the axis.
8 has an insertion hole 24 through which the pin body 18 a is inserted, and is press-fitted into the damper cover 16. The damper rubber 15 is incorporated into the damper cover 16 by the inner side surface of the head 18b by inserting the pin body 18a into the insertion hole 24 and fixing the armature 22 by the caulking portion 18c at the tip. Will be retained.

The insertion hole is formed in the surface of the damper rubber 15, that is, a surface (hereinafter referred to as a pressed surface) 15 a facing the front opening of the damper cover 16 and pressed by the head 18 b of the torque transmission pin 18. A cylindrical projection 25 surrounding the opening edge of the projection 24 is integrally provided.

The damper rubber 15 is assembled in a compressed state in the damper cover 16 as shown in FIG. 2 (a), and urges the armature 22 in a direction away from the rotor 7 by its repelling force. ing. That is, the damper rubber 15 is attached to the bottom 16 of the damper cover 16 while the head 18b of the torque transmission pin 18 is in contact with the cylindrical projection 25.
a.

The armature 22 has a disc shape, though not shown in its entirety, and has a stepped hole 23 and a magnetic flux formed at an interval on the same circle at a position dividing the circumferential direction into three equal parts. An arc-shaped elongated hole 27 for bypassing the hole is formed. Then, a surface (friction surface) 2 facing the rotor 7
The stopper plate 1 is arranged such that the surface 2c faces the surface (friction surface) 7d of the rotor 7 while maintaining a predetermined air gap G.
0 through a torque transmission pin 18.

The movement of the armature 22 to the damper rubber 15 side is restricted by the stopper plate 10. As shown in FIG. 2B, when the electromagnetic clutch 1 is excited, the magnetic flux of the exciting coil 8a constituting the exciting device 8 magnetically attracts the friction surface 22c of the armature 22 to the friction surface 7d of the rotor 7. Is adsorbed. When the electromagnetic clutch 1 returns to the non-excited state,
As shown in FIG. 2A, the armature 22 is separated from the rotor 7 and returned to the initial state by the elastic return force of the damper rubber 15.

The rotor 7 has a cylindrical outer peripheral wall 7a and an inner peripheral wall 7b, and a disk portion 7 connecting one end of these two walls.
c is integrally mounted on the cylindrical portion 5a of the housing 5 via the bearing 6 so as to be rotatable. A V-shaped groove 32 is formed on the outer surface of the outer peripheral wall 7a.
A V-belt (not shown) of a vehicle accessory other than the vehicle engine side or the compressor 2 is hung on the groove 32. The surface of the disk portion 7c forms the friction surface 7d, and has an arc-shaped long hole 34 for bypassing magnetic flux.

An annular groove 35 formed by the outer peripheral wall 7a, the inner peripheral wall 7b, and the disk portion 7c is open on the side opposite to the armature 22, and incorporates the exciting device 8. The exciting device 8 includes the housing 5
The yoke 8b is supported by a mounting plate 36 provided in the above and is inserted into the annular groove 35 in a non-contact manner, and the exciting coil 8a and the like are incorporated into the yoke 8b via a coil bobbin 8c. Although not shown in detail, 8d is a power supply unit for supplying power to the exciting coil 8a.

The electromagnetic clutch 1 having such a structure
When the excitation coil 8a is energized, the magnetic flux is diverted from the rotor 7 to the armature 22 to form a double-flux type magnetic circuit, so that the friction surface 22c of the armature 22 Magnetically attracted to the friction surface 7d {see FIG. 2 (b)}. Thereby, the rotation of the rotor 7 is transmitted to the rotating shaft 3 and drives the compressor 2.

When the power supply to the exciting coil 8a is cut off, the magnetic flux disappears.
The transmission of power to the rotating shaft 3 is cut off by being separated from the rotor 7 by the elastic return force of. Therefore, compressor 2
Stops. Armature 22 separated from rotor 7
Is a damper rubber 1 as shown in FIG. 1 and FIG.
The elastic restoring force of 5 causes the stopper plate 10 to abut and be held.

According to this embodiment, in the electromagnetic clutch 1 having the above-described structure, at least the inside of the outer peripheral edge of the head 18b of the torque transmitting pin 18 as the headed pin is formed in an arc shape (the arc-shaped portion 40). ), A surface 41 that retreats in the axial direction as it goes outward, on a radially outer portion of the surface of the damper rubber 15 that faces the head 18b.
Is formed.

That is, the surface 41 that retreats in the axial direction gradually moves toward the armature 22 toward the outside in the radial direction from a portion facing the arc-shaped portion 40 on the outer peripheral edge of the head portion 18b of the torque transmission pin 18. It may be formed on either the inclined tapered surface or the curved surface. In this embodiment, the damper rubber 15 is formed in a tapered surface shape in which the height of the end face 15a gradually decreases from the portion facing the arc-shaped portion 40 inside the outer peripheral edge of the head portion 18b toward the outside in the radial direction. I have.

As described above, the end face 15a of the damper rubber 15 which is pressed by the inner surface of the head 18b of the damper rubber 15 and is elastically deformed is formed with the surface 41 which retreats in the axial direction, thereby compressing the head 18b. Bulges due to the elastic deformation caused by the arc-shaped portion 40 inside the outer peripheral edge of the head 18b.
The amount of swelling of the portion that comes into contact with is reduced.

According to such a configuration, the armature 2
2 is pressed by the arc-shaped portion 40 inside the outer peripheral edge of the head portion 18b of the torque transmission pin 18 when the magnetic force is attracted to the rotor 7 by the excitation device 8, a large compressive stress is generated in the local portion of the damper rubber 15. Do not let. Also, this arc-shaped portion 4
By forming the cross-sectional shape of the damper rubber 15, particularly the outer peripheral side of the end face on the side of the head 18 b, with the curved surface 41 so as to escape the zero, the contact with the arc-shaped portion 40 can be more reliably prevented. .

Therefore, according to such a structure, even if the damper rubber 15 is elastically deformed by being pressed by the inner surface of the head 18b of the torque transmitting pin 18, the arc-shaped portion 40 inside the outer peripheral edge of the head 18b is formed. Is small due to the elastic deformation of the damper rubber 15 opposed to
Even if the outer peripheral edge of the head 18b slides on the end face of the damper rubber 15, no crack is generated.

In this embodiment, FIGS. 2A and 2B
As shown in FIG. 3, the inside of the open end of the damper cover 16 forming the damper rubber accommodating portion is formed by an arcuate surface 16b. With such a structure, when the damper rubber 15 rises due to elastic deformation,
Can prevent damage.

In the electromagnetic clutch 1 using the damper rubber 15, when the armature 22 is magnetically attracted to the rotor 7, the armature 22 is pressed by the arc-shaped portion 40 inside the outer peripheral edge of the head 18 b of the torque transmission pin 18. No local compressive stress is generated on the end surface 15a of the damper rubber 15. Therefore, the crack, which has been a problem in the related art, can be prevented only by changing the sectional shape of the damper rubber 15 without changing the design dimensions of the damper device of the existing product.

According to such a structure, the reduction of the armature suction noise can be satisfied, and the operation failure of the armature 22, for example, the suction time in which the armature 22 is magnetically attracted to the rotor 7 side becomes longer, or the armature 22 is moved to the rotor 7 side. The occurrence of cracks in the damper rubber 15 can be prevented without causing problems such as slowing down of the operation of separating from the side.

According to the structure described above, the damper rubber 15 is connected to the torque transmitting pin 1 similarly to the conventional electromagnetic clutch.
8 is elastically deformed by being pressed by the inner side surface of the head 18b. However, since the amount of protrusion of the end face of the damper rubber 15 facing the arcuate portion 40 inside the outer peripheral edge of the head 18b is small, the end face of the damper rubber 15 is A crack does not occur due to sliding contact with the arc-shaped portion 40, and the durability of the damper rubber 15 can be improved.

According to the above-described embodiment, when the armature 22 is magnetically attracted to the rotor 7, the damper rubber 15 moves between the bottom 16a of the damper cover 16 and the head 18b of the torque transmitting pin 18. It is sandwiched and compressed. Further, the rotational direction side of the damper rubber 15 is sandwiched and compressed between the torque transmitting pin 18 and the inner peripheral surface of the damper cover 16 by the load of the rotary shaft 3 of the compressor 2.

The electromagnetic clutch 1 provided with the above-described damper rubber 15 has the friction surface 22 c of the armature 22 having the rotor 7.
The vibration when magnetically attracted to the friction surface 7d of the
Therefore, the generation of the suction sound of the armature 22 can be prevented. The electromagnetic clutch 1 is provided with a cylindrical projection 25 on the surface of the damper rubber 15. Immediately before the armature 22 is magnetically attracted to the rotor 7, the entire inner surface of the head 18 b of the torque transmission pin 18 is provided. Since the structure for pressing the pressed surface 15a of the damper rubber 15 is employed, the impact when the armature 22 is magnetically attracted to the rotor 7 is reduced, and the armature 2
2, the generation of the suction noise can be suppressed.

The present invention is not limited to the structure described in the above embodiment, and it goes without saying that the shape, structure, etc. of each part can be appropriately modified or changed. For example, the shape and structure of the damper rubber 15, the damper rubber housing 16, the headed pin 18, the shape and structure of the armature hub 11, particularly the shape and structure of the flange portion thereof, and the shape and structure of each part such as the structure of the exciting device 8 may be appropriately changed. Be free.

The outer periphery of the outer periphery of the head 18b of the torque transmission pin 18 may be formed in an arc shape like the inside.

Further, in the embodiment of the present invention, the electromagnetic clutch 1 mounted on an auxiliary machine for an automobile (compressor for a car air conditioner) has been described. The present invention can be applied to any electromagnetic coupling device.

[0046]

As described above, according to the electromagnetic coupling device according to the present invention, the damper rubber which is compressed by the head of the headed pin and elastically deformed when the armature is magnetically attracted is larger than the outer peripheral edge of the head. The amount of swelling on the radially outer side can be reduced, and swelling beyond the outer peripheral edge of the head can be prevented. Therefore, the damper rubber does not easily come into contact with the outer peripheral edge of the head.

According to the present invention, when the armature is magnetically attracted to the rotor, a compressive stress is not generated at a portion of the damper rubber pressed by the outer peripheral edge of the head of the headed pin. Escape of the pressed portion can be dealt with only by changing the cross-sectional shape of the damper rubber without changing the design dimensions of the damper device of the existing product.

According to the present invention, the armature suction noise can be reduced and the operation of the armature separated from the rotor, the operation failure of the armature (the suction time for magnetically attracting the armature to the rotor increases, and the operation of separating the armature from the rotor) can be improved. This can economically prevent the damper rubber from cracking without causing problems such as slowing down.

According to the present invention, similarly to the conventional electromagnetic clutch, the damper rubber is elastically deformed by being pressed by the inner side surface of the head of the headed pin. The protrusion of the end face of the damper rubber opposed to the head is small, and the end face of the damper rubber does not slidably contact the inner corner of the outer peripheral edge of the head to cause a crack, thereby improving the durability of the damper rubber.

[Brief description of the drawings]

FIG. 1 is a sectional view showing one embodiment of an electromagnetic clutch to which an electromagnetic coupling device according to the present invention is applied.

FIG. 2A is an enlarged cross-sectional view of a main part of a housing portion of a damper rubber for movably holding an armature on a flange portion of an armature hub in the electromagnetic clutch of FIG. 1;
FIG. 3B is a cross-sectional view of a main part showing a compression deformation state of the damper rubber when the armature moves.

FIG. 3 is an enlarged view of a damper rubber mounting portion characterizing the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Electromagnetic clutch, 2 ... Compressor, 3 ... Rotary shaft, 4
... armature assembly, 5 ... housing, 7 ... rotor,
8 Exciting device, 10 Stopper plate, 11 Armature hub, 15 Damper rubber, 15a Pressed surface, 1
6 damper cover, 16a arcuate surface, 18 torque transmitting pin (headed pin), 18a pin body, 18b head
22: armature, 24: insertion hole, 25: cylindrical projection,
40: arc-shaped portion, 41: surface retreating in the axial direction.

Claims (2)

[Claims] An armature hub mounted on a rotating shaft, a damper rubber housed in a damper rubber housing portion provided on a flange portion of the armature hub from one side, and having a through hole through which a pin body of a headed pin penetrates; An armature which is fixed by a caulking portion at the tip of the pin body penetrating the damper rubber and the flange portion of the armature hub and which moves forward and backward in the axial direction on the other side surface of the flange portion; and the armature resists the elasticity of the damper rubber. An electromagnetic coupling device having an exciting device for magnetically attracting, wherein at least the inside of the outer peripheral edge of the head of the headed pin is formed in an arc shape, and a cylindrical projection is integrally provided on the opening edge of the insertion hole of the damper rubber. In addition, a surface that retreats in the axial direction as it goes outward is formed on a radially outer portion of the surface facing the head. And an electromagnetic coupling device. 2. The electromagnetic coupling device according to claim 1, wherein the surface of the damper rubber that retreats in the axial direction is directed radially outward from a portion of the headed pin facing the arc-shaped portion of the outer peripheral edge of the head. An electromagnetic coupling device formed in one of a tapered surface and a curved surface whose height gradually decreases.