JP2001317565A - Electromagnetic spring clutch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electromagnetic spring clutch provided with a coil spring having corrosion resistance. SOLUTION: In the electromagnetic spring clutch used for a water pump heater as an automotive auxiliary machine, coil spring 4 is disposed on a winding surface of an input pulley 1 and an output hub 7. The coil spring 4 is made by plating a surface of machined spring steel with an yellow chromate (rust preventive processing), and has corrosion resistance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic spring clutch, and more particularly, to an electromagnetic spring clutch used for intermittently driving automotive accessories such as a water pump heater and a compressor by a driving force from an engine.

[0002]

2. Description of the Related Art For example, an electromagnetic spring clutch used for automotive accessories such as a water pump heater and a compressor connects an input pulley and an output hub as needed, and rotational driving force from an engine is used. Is transmitted to the rotating shaft of the vehicle accessory via the input pulley and the output hub. Conventionally, this type of electromagnetic spring clutch includes an electromagnetic coil on the side of an input pulley that rotates by receiving rotational driving force from an engine. Also, on the output hub side provided on the rotating shaft of the auxiliary equipment for automobiles,
An armature is provided that is attracted to or released from the input pulley in response to energization or interruption of energization of the electromagnetic coil. In addition, one end is connected to the armature, and the other end is connected to the output hub, and includes a coil spring disposed on a winding surface set on the input pulley and the output hub. Then, when the armature is attracted to the input pulley by energizing the electromagnetic coil, the coil spring is wound around the winding surface of the input pulley and the output hub, and the rotational torque of the input pulley is transmitted to the automobile through the output hub by the tightening force. It is transmitted to the rotating shaft of the auxiliary machine.

[0003]

In the above-mentioned conventional electromagnetic spring clutch, the coil spring is made of steel. When an electromagnetic spring clutch having such a coil spring is used for a device installed indoors such as a copying machine or a printer, corrosion of the coil spring hardly occurs. However, when an electromagnetic spring clutch having such a coil spring is used for an auxiliary machine for an automobile, the coil spring may be exposed to a corrosive environment outdoors. For example, when salt is brought into the electromagnetic spring clutch when traveling on a seaside road or when a deicing agent is brought in when traveling on a road in winter, the metal part of the coil spring is corroded by the salt or the deicing agent. Is concerned.
If the coil spring is corroded, there is a possibility that the rotational torque transmitted to the auxiliary machine for the vehicle is reduced, and if the corrosion is severe, the coil spring itself may be damaged. As described above, the coil spring is an important member in transmitting the rotational driving force from the engine to the rotating shaft of the automotive accessory through the input pulley and the output hub. There is a demand for corrosiveness.

Accordingly, the present invention has been made in view of the above points, and an object of the present invention is to provide an electromagnetic spring clutch having a coil spring having corrosion resistance.

[0005]

In order to solve the above-mentioned problems, an electromagnetic spring clutch according to the present invention is configured as described in claims 1 and 2. Here, claim 1,
The terms described in other claims and the detailed description of the invention are to be interpreted as follows unless otherwise limited. (1) “Auxiliary equipment for automobiles” includes a compressor, a viscous heater, and the like in addition to a water pump heater.

According to the electromagnetic spring clutch of the first aspect, the use of the rust-preventive coil spring makes it possible to prevent the coil spring from being corroded. Here, the coil spring is a dacro treatment (a treatment of immersing in a solution of a zinc chromate compound and baking at high temperature to adhere a zinc chromate composite film) to the steel material, as described in claim 2. , Chromate treatment, or black dyeing treatment (treatment of adhering an oil film by dipping in high-temperature machine oil) is preferred. Thus, a coil spring having corrosion resistance and low processing cost can be realized.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the electromagnetic spring clutch according to the present invention will be described below. In the present embodiment, a water pump heater, which is an auxiliary machine for an automobile, will be described.

First, the configuration and the like of an electromagnetic spring clutch according to an embodiment of the present invention will be described with reference to FIG. Here, FIG. 1 is a longitudinal sectional view of an electromagnetic spring clutch according to one embodiment of the present invention. As shown in FIG.
The substantially cylindrical input pulley 1 as an input-side member in the present invention is an outer peripheral of a small-diameter cylindrical portion 2a formed at one end of a pump housing 2 of a water pump heater provided as a heating auxiliary, for example, as an auxiliary machine for an automobile. Are rotatably supported by bearings 3. Then, the rotational driving force of the engine E as a driving source is taken out via a V-belt,
The input pulley 1 is driven by this rotational driving force. The input pulley 1 is made of a magnetic material, for example, a steel material, and is subjected to a chromate treatment for rust prevention.

The input pulley 1 has a cylindrical portion 1a that protrudes concentrically from one (left side in the drawing) side toward the anti-pump housing 2 (left side in the drawing), and the outer periphery of the cylindrical portion 1a. The surface constitutes a winding surface of the coil spring 4. A stator 5 containing an annular electromagnetic coil 5 a is fixed to the pump housing 2 by a circlip (fixing tool) 6. The stator 5 is provided on the other side of the input pulley 1 (right side in the figure). It is inserted into an annular concave groove 1b formed on the side surface. In addition, concave groove 1
A small gap is formed between the groove b and the outer peripheral surface of the stator 5, so that when the input pulley 1 rotates, the groove 1b does not contact the stator 5.

The output hub 7 as an output-side member in the present invention has a cylindrical portion 7a and a flange portion 7b.
a is spline-fitted to the outer peripheral end of the pump shaft 8 (corresponding to the rotating shaft in the present invention) of the water pump heater,
It is fixed by a bolt 10 via a thick washer 9 and is prevented from falling off. The outer peripheral surface of the flange portion 7b of the output hub 7 is aligned with the outer peripheral surface of the cylindrical portion 1a of the input pulley 1 to form a winding surface of the coil spring 4. Also,
An electromagnetic coil 5 is provided on the side surface of the input pulley 1 on the side of the cylindrical portion 1a.
An annular armature 11 (corresponding to the suction / removal member in the present invention) is disposed opposite to a.

A coil spring 4 as a torque transmitting member is disposed on a winding surface formed by the outer peripheral surface of the cylindrical portion 1a of the input pulley 1 and the outer peripheral surface of the flange portion 7b of the output hub 7. One end of the spring 4 is hooked and coupled to a concave portion formed on the inner peripheral side of the armature 11, and the other end is coupled to a concave portion formed on the outer peripheral side of the flange portion 7b. The coil spring 4 is made of, for example, processed spring steel (piano wire (SWP
B)) has a surface subjected to yellow chromate plating. Accordingly, the coil spring 4 has corrosion resistance. Therefore, even if salt or a deicing agent is brought into the electromagnetic spring clutch and the coil spring 4 is exposed to a corrosive environment, the coil spring 4 is not damaged. Corrosion of the spring 4 can be prevented.

The output hub 7, the coil spring 4, and the armature 11 are covered by a spring cover 12. That is, the spring cover 12
Is formed in a shape having a cylindrical portion 12a and a flange portion 12b capable of wrapping the above three components from outside.
The flange portion 7 of the output hub 7 is formed by the cylindrical portion 12a.
The outer peripheral portion is arranged so as to wrap around the side surface of the coil spring 4 from outside, and the peripheral portion is fastened by a plurality of bolts 13 in a state of being superimposed on the side surface of the flange portion 7b.

The collar 12b of the spring cover 12
The armature 11 has an outer peripheral edge protruding in a cylindrical shape in the axial direction, and an armature 11 is fitted on the inner peripheral surface of the cylindrical portion so as to be slidable in the axial direction. On the surface of the armature 11 facing the spring cover 12, magnets 14 are attached at a plurality of locations on the circumference. Therefore, when the electromagnetic coil 5a is not energized, the armature 11 is attracted to the flange 12b of the spring cover 12 via the magnet 14.

Next, the operation of the electromagnetic spring clutch configured as described above will be described. First, in the state where the electromagnetic coil 5a is not energized, the magnet 14 is attracted to the spring cover 12 as described above, so that air is generated between the friction surface 1c of the input pulley 1 and the friction surface 11a of the armature 11. A gap called a gap is maintained, only the input pulley 1 rotates, and the output hub 7 is stationary. When the electromagnetic coil 5a is energized in such a state,
The electromagnetic coil 5a is excited, and the friction surface 1 of the armature 11 is
1 a is attracted to the friction surface 1 c of the input pulley 1. As a result, the armature 11 is rotated, and the coil spring 4 is wound around the outer peripheral surface of the cylindrical portion 1a of the input pulley 1 and the flange portion 7b of the output hub 7, and the rotational torque of the input pulley 1 is output by the tightening force. The power is transmitted to the pump shaft 8 via the hub 7.

According to the electromagnetic spring clutch of the present embodiment configured as described above, since the coil spring 4 has been subjected to a rust-preventive treatment (yellow chromate plating), it is possible to prevent the coil spring 4 from being corroded. Can be prevented. Further, since the rust prevention treatment by yellow chromate plating is used, the processing cost is lower than, for example, the case where a resin coating is used.

It should be noted that the present invention is not limited to only the above-described embodiment, and various applications and modifications are conceivable. For example, each of the following embodiments to which the above embodiment is applied may be implemented.

In the above embodiment, the coil spring 4
Used the one in which the surface of the machined spring steel was subjected to yellow chromate plating (chromate treatment). For example, the coil spring used the dacro treatment of the surface of the machined spring steel (dipped in a zinc chromate compound solution, By baking dry to adhere the zinc-chromate composite film),
Alternatively, a black dyeing treatment (a treatment in which an oil film is adhered by dipping in high-temperature machine oil) may be used. Further, the coil spring itself may be made of a material having corrosion resistance. Note that this case also corresponds to the form in which the rust prevention treatment is performed in the present invention.

In the above embodiment, the case where the electromagnetic spring clutch is provided in the water pump heater has been described. However, the present invention can be applied to an electromagnetic spring clutch provided in an auxiliary machine for an automobile other than the water pump heater. .

[0019]

As described above, according to the present invention,
An electromagnetic spring clutch including a coil spring having corrosion resistance can be realized.

[Brief description of the drawings]

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

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Input pulley 4 ... Coil spring 5 ... Stator, 5a ... Electromagnetic coil 7 ... Output hub 8 ... Pump shaft 11 ... Armature 12 ... Spring cover

Claims (2)

[Claims] An input-side member which rotates by receiving a driving force of an engine, an output-side member provided on a rotating shaft of an auxiliary machine for an automobile, an electromagnetic coil, and an energizing or de-energizing of the electromagnetic coil. A suction / detachment member which is adsorbed or desorbed to / from the input side member, and one end is connected to the suction / detachment member, and the other end is connected to the output side member, respectively; A coil spring disposed on a surface, and energizing the electromagnetic coil so that the adsorption / desorption member is attracted to the input side member, and the coil spring is wound around the input side member and the output side member. An electromagnetic spring clutch that wraps around an attached surface and transmits a rotational torque of the input-side member to a rotation shaft of the auxiliary machine for an automobile via the output-side member by the tightening force; Electromagnetic spring clutch, characterized in that the anticorrosive treatment has been made. 2. The electromagnetic spring clutch according to claim 1, wherein the spring is made of a steel material by any of dacro treatment, chromate treatment, and blackening treatment. .