JPS58193939A - Electromagnetic spring clutch - Google Patents

Abstract

PURPOSE:To shorten the shaft length of an electromagnetic spring clutch, by making the titled clutch into structure wherein an armature is provided between an exciting coil and a rotor and a spring for transfer of torque is inserted into the inside of the exciting coil. CONSTITUTION:The inner cylindrical part 16 of a rotor 15 is supported turnably by a shaft 19 through a bearing 23. An exciting coil 17 is provided on the inside of the rotor 15 and is secured to a front housing of a compressor with a screw 18b through a yoke 18 and a stay 18a. An armature 21 made of iron arranged between a non-magnetic material plate 25 and the rotor 15 at the time of non-electrification of the exciting coil 17 is attracted by a magnet 26. A coil spring 22 for transmission of torque is inserted into an inner circumferential side of the yoke 18 through welding with pressure, its one end, a hook part 22a is supported in a notched part 21 of the armature and the other end, a hook part 22b is supported by a hole part 20 of an output hab 20 secured on a shaft 19.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention generally relates to improvements in electromagnetic spring clutches, and is suitable for use in electromagnetic spring clutches used, for example, in connection and disconnection of compressors for air conditioners in automobiles. It is something.

A typical structure of a conventional electromagnetic sublink clutch of this kind is as shown in FIG. Due to the excitation of the magnetic flux generated around the
The armature 5 is magnetically attracted and rotates together with the rotor 1, and one end is hooked to the notch 12 of the armature 5,
A coil spring 6 whose other end is hooked to a notch 18 of the output hub 4 connects the boss portion 1a of the rotor l and the peripheral body portion 4a of the output hub 4.
When the key 10 and the nut 11 are tightened to the outside, the torque of the rotor l is transmitted through the output hub 4 by this tightening force, and the key 10 and the nut 11 are
The structure is such that the signal is transmitted to the shaft 3 of the compressor, which is fixed to the shaft 3 of the compressor. The coil spring 6 is connected to the output hub 4
The armature 5 is supported by the flange portion 7a of the rotor 1411 of the spring cover 7, and the armature 5 is supported by the flange portion 7a of the rotor 1411 of the spring cover 7. It is held slidably and rotatably by. moreover.

The rotor 1 is rotatably supported by a bearing 9 attached to the outer periphery of a front housing 8 of the compressor. The permanent magnet 14 is used to release the armature 5 from the friction surface of the rotor 1 when the excitation is released.

However, in the electromagnetic spring clutch configured as described above, the flange portion 1a of the rotor 1 around which the spring 6 is wound is tightened.
protrudes in the axial direction from the friction surface of the rotor 1 and armature 5 (in Fig. 1, the flange portion 1a protrudes to the right from the friction surface), so the axial length of the entire clutch inevitably increases. There are drawbacks.

The present invention has been made in view of the above points, and has a structure in which an armature is disposed between an excitation coil and a rotor, and a spring for transmitting torque is inserted inside the excitation coil, thereby increasing the axial length of an electromagnetic spring clutch. The purpose is to shorten the

Embodiment ζ of the present invention shown in the drawings will be described below.

FIG. 92 shows a longitudinal sectional view of an embodiment of the present invention, in which a rotor (made of iron) 15 with an input boob portion 15a integrally formed on the outer periphery is attached to a shaft 19 of an air conditioning compressor for an automobile. The inner cylindrical portion 16 is rotatably supported via a bearing 28. Further, the excitation coil 17 is arranged inside the rotor 15, and is connected to the front housing of the compressor (not shown) via a 9WA iron 1B and a stay 188, for example, with a screw ta.
It is fixed at b. A non-magnetic plate 26 made of metal such as aluminum or brass is fixed to the yoke 18 that houses the excitation coil 17 at a position on the rotor 15 side by caulking, welding, or other methods. The plate 25 has a substantially circular ring shape, and permanent magnets 26 are embedded and fixed at several locations (for example, 4 locations) at equal intervals in the circumferential direction. This magnet 26 is connected to the non-magnetic plate 2 when the excitation coil 17 is not energized.
5 and the rotor 16. Note that the non-magnetic plate 25 is provided with a flange portion 25& for eliminating play in the radial direction of the armature 21. On the other hand, a coil spring 22 for torque transmission is provided on the inner peripheral side of the yoke 18.
is inserted by pressure welding.

The hook portion 22& at the - end is located within the notch 21B of the armature 21, and the hook portion 22b at the other end is supported by the hole 2Q& of the output hub 20 fixed to the shaft 19 with a key 24. . In the configuration of this example, when assembling, the yoke 18 that houses the excitation coil 17 is first fixed to the front housing of the compressor with screws 18b, and then the output hub that supports one end 22b of the coil spring 22 is attached. 20 into the shaft 19 via the key 24.

Next, the armature 21 is assembled to the non-magnetic plate 25 so that the notch 21 & of the armature 21 and the hook 22 & of the coil spring 22 fit together, and then the bearing 28 fixed to the rotor 15 is attached to the nut 27 . It is fixed and assembled to the shaft 19 using a washer 27& to prevent it from moving in the axial direction.

The operation of the electromagnetic spring clutch according to the present invention in the above configuration will be explained. When the excitation coil 17 is energized, the yoke 18, which is a fixed member, and the input rotor 15, which is being rotated by the engine (not shown), are magnetized, and magnetic flux flows along the path indicated by the broken line f, so that the electric current absorption force The armature 21 separated from r1gl is attached to the rotor 15.
suction to. Then, due to the frictional force between the armature 21 and the rotor 15, the spring 22 whose one end is restrained by the armature 21 is tightened in the rotational direction of the rotor 15.

This spring 22 is tightened around the outer peripheral surface of the inner cylindrical portion 16 of the rotor 15 and the outer peripheral surface of the output hub 20. As a result, the rotor 15 and the output hub 20 are integrally connected,
Since the rotation of the rotor 15 is transmitted to the shaft 19, the air conditioning compressor is put into operation.

On the other hand, when the power supply to the excitation coil 17 is cut off.

Since the magnetic flux f disappears, the armature 21 is separated from the rotor 15 by the attractive force of the permanent magnet 26 and returns to the position shown in FIG. As a result, the spring 22 also returns to the illustrated position, breaking the connection between the rotor 15 and the output hub 20, thereby stopping the compressor. When the compressor is stopped (when the excitation coil is not energized), the spring 22 is connected to the yoke 1.
Since it is in pressure contact with the inner circumferential surface of 8, no abnormal noise is generated due to vibration or the like.

In the embodiment shown in FIG. 2, the rotor 15 is directly supported by the shaft 19 of the compressor via the bearing 28, so it is necessary to increase the diameter of the shaft 19 due to the strength of the shaft 19. be. On the other hand, in the embodiments shown in FIGS. 8 and 4, a bearing 28 is disposed on the outer periphery of the yoke 18 that houses the excitation coil 17, and the structure is such that the bearing 28 supports the input pulley portion 15 & of the rotor 15. Therefore, the diameter of the shaft 19 can be reduced. and.

In this embodiment, a portion 28 of the outer ring of the bearing 28 fitted into the inner periphery of the input pulley portion 15 & of the rotor 15
& is made to protrude from a slit 29 provided in the rotor 15, and the circlip 80 is fitted into the groove 28b provided in the protrusion 28&.

The rotor 15 and bearing 28 are fixed. By adopting such a configuration, the shaft 19 can be made smaller in diameter and the entire clutch can be made smaller in diameter than the embodiment shown in Figure #I2, and at the same time, the shaft 19 can also be shortened, and torsional resonance of the shaft 19 can also be prevented. can.

Further, although the above-mentioned embodiments have been described with reference to the case where the compressor is applied to an automobile air conditioning compressor, the present invention is of course not limited to such an application, but can be widely applied to various other applications.

In addition, the input pulley portion 15B of the rotor 15 is not integrally formed, but is formed separately and joined to the rotor 15, etc.
It can be transformed into various shapes.

As detailed above, 1. According to the present invention, the flange portion 1a of the rotor in the conventional structure can be eliminated, and the axial length of the entire clutch can be shortened accordingly. This has the excellent effect of facilitating installation even in a small installation space.

Further, the spring cover 7 in the conventional structure can be eliminated, and the output hub and rotor have simpler shapes than in the conventional structure, resulting in cost reduction.

[Brief explanation of drawings]

111 is a vertical cross-sectional view of a conventional clutch, FIG. 2 is a vertical cross-sectional view of one embodiment of the clutch of the present invention, FIG. 8 is a vertical cross-sectional view of another embodiment of the clutch of the present invention, and FIG. It is a side view taken from arrow A in the figure. 15...rotor, 15&...input boolean section, 16...
... Inner cylindrical part, 17... Exciting coil, 18... Yoke, 19... Shaft, 20 Pa・Output hub, 21... Armature, 22... Coil spring, 28.28...
··bearing. Representative Patent Attorney Takashi Okabe 19

Claims (3)

[Claims] (1) An excitation coil, a yoke in which the excitation coil is housed, an input couple rotor to which one rotation is transmitted from the drive source, and an excitation coil located between the yoke and the rotor, and the excitation coil. An armature that is attracted to the rotor when the coil is energized, and an outer peripheral surface of an output hub that is located on the inner peripheral side of the yoke and that is connected to the inner cylindrical part of the rotor and the driven shaft. one end of this coil spring is locked to the output hub, and the other end is locked to the armature, and when the armature is attracted to the rotor, The electromagnetic spring clutch is configured such that the coil spring is wound tightly on the outer circumferential surface of the output hub and on the outer circumferential surface of the inner cylindrical portion of the rotor, so that the protruding hub and the rotor are integrally connected. (2) The electromagnetic spring clutch according to claim #I1, wherein a bearing that rotatably supports the rotor is provided between the inner cylindrical portion of the rotor and the shaft. (3) An electromagnetic spring according to claim 1, wherein a bearing that rotatably supports the rotor is provided between an inset portion on the outer circumference of the rotor and an outer circumference of the yoke. clutch.