JPH0724664Y2 - Electromagnetic coupling device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an electromagnetic coupling device used as an electromagnetic clutch for transmitting rotational torque or an electromagnetic brake for braking.

[Prior Art] Generally, a friction type electromagnetic coupling device such as an electromagnetic clutch is
The magnetic flux generated by the excitation of the electromagnetic coil is passed between the rotor and the armature whose friction surfaces are opposed to each other, and the magnetic attraction force and the spring force that opposes the magnetic force force the friction surfaces into contact with each other or separate them from each other. As a result, the rotational torque is transmitted or cut.

The electromagnetic coil in such an electromagnetic clutch is housed in the annular groove of the yoke.
Various types have been conventionally proposed. For example, Mitsuko Sho 58-333
What is disclosed in Japanese Patent Publication No. 05 is such that an electromagnetic coil is wound around a coil bobbin having an L-shaped cross section and formed in an annular shape.
This is accommodated in the annular groove of the yoke, the opening of the annular groove is closed by an annular lid, and the lid is prevented from coming off by a caulking portion integrally provided on a part of the peripheral edge of the opening. The impregnating varnish is injected into the space of the annular groove from a plurality of holes formed in the lid to fix the electromagnetic coil, thereby preventing vibration and movement due to vibration and achieving electrical insulation.

[Problems to be Solved by the Invention] However, in such a conventional electromagnetic clutch, there is a work of injecting an impregnated varnish from an opening of a lid in order to insulate the electromagnetic coil from the outside, and thus productivity is poor. Also,
The varnish is not sufficiently injected into the annular groove because it is wound from the wound electromagnetic coil to the electromagnetic coil, the bobbin / electromagnetic coil outer peripheral surface, and the inner peripheral surface of the yoke annular groove, respectively. As a result, the electromagnetic coil shakes and rotates due to the vibration, and the coil is broken.

Therefore, the present invention has been made in view of the above-mentioned conventional drawbacks, and an object thereof is to securely fix an electromagnetic coil without injecting an impregnating varnish, improving productivity, and An object of the present invention is to provide an electromagnetic coupling device capable of preventing a coil disconnection accident.

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present invention provides a yoke having an annular groove and an electromagnetic coil which is formed in an annular shape having a U-shaped cross section and is previously wound into a polygonal shape. A coil bobbin that is housed in a state in which a coil is exposed in a substantially half portion and is inserted into the annular groove of the yoke with the opening side thereof facing the same direction, and the coil bobbin is formed in an annular shape having a U-shaped cross section. A cover which is open to the opening side of the electromagnetic coil and which is capped on the exposed portion of the electromagnetic coil protruding from the coil bobbin and press-fitted into the annular groove of the yoke, and by partially caulking the opening end of the yoke. The cover is fixed in the yoke, and at least one of the coil bobbin and the annular groove formed in the cover matches the shape of the peripheral surface of the electromagnetic coil having a polygonal shape. It is a rectangular annular groove.

[Operation] In the present invention, the electromagnetic coil is formed in a polygonal shape, and the annular groove of at least one of the coil bobbin and the cover into which the electromagnetic coil is fitted is formed in a polygonal shape that matches the electromagnetic coil. Prevents the rotation of the electromagnetic coil.

[Embodiment] Hereinafter, the present invention will be described in detail based on an embodiment shown in the drawings.

FIG. 1 is a sectional view showing an embodiment in which the electromagnetic coupling device according to the present invention is applied to an electromagnetic clutch for a compressor of a car cooler, FIG. 2 is a front view of a yoke, and FIG. 3 is an enlargement of an electromagnetic coil storage portion. A sectional view and FIG. 4 are sectional views taken along line IV-IV in FIG. In these drawings, a yoke 2 made of an annular body having a U-shaped cross section is fixedly supported in a housing 1 of a compressor via a support plate. The electromagnetic coil 4 fixed by the structure described in detail is housed and connected to the power supply via the lead wire 5. A bearing 6 is fitted on the outer periphery of the nose portion 1a of the housing 1, and its axial movement is restricted by a snap ring. An annular groove 8a for engaging the yoke 2 is fitted to the outer ring of the bearing 6. The rotor 8 provided with
The movement in the axial direction is restricted by the snap ring 9 and the snap ring 9, and the snap ring 9 is fitted and fixed.

Reference numeral 10 denotes a V-pulley which is fitted and integrated on the outer peripheral surface of the rotor 8. A V-belt (not shown) is stretched between the V-pulley 10 and a drive source such as an automobile engine. The rotor 8 is configured to be rotationally driven from the drive shaft side.

On the other hand, the housing 1 is penetrated through the central hole 1b of the housing 1.
The armature hub 12 formed in the shape of a disc with a boss is fixed to the tip of the rotary shaft 11 supported by a bearing (not shown) on the side by bolts 13 and washers 14. An annular armature 16 is fixedly supported between the rotor 8 and the armature hub 12 at the free end portion of the leaf spring 15 that is tacked to a plurality of equal parts in the direction. The armature 16 is biased by the leaf spring 15 in the direction away from the rotor 8.

Next, the fixing structure of the electromagnetic coil 4 will be described.

The electromagnetic coil 4 formed in a ring shape is inserted into a coil bobbin 17 having a U-shaped cross section in a state where it is preliminarily fixed with a bond wire, and a half portion thereof is inserted into the coil bobbin 17.
Exposed to the outside. The exposed portion of the electromagnetic coil 4 is covered with a cover 18 having an annular U-shaped cross-section, and the outer cylindrical portion 18a and the inner cylindrical portion 18b are the peripheral surface of the electromagnetic coil 4. And the inner peripheral surface of the annular groove 3 are press-fitted to fix the electromagnetic coil 4. At the open end of the annular groove 3 of the yoke 2, a plurality of caulking pieces 19 are cut and raised in parallel in the circumferential direction, and the cover 18 is pulled out by bending the caulking pieces inward. To prevent the electromagnetic coil 4 from being fixed. Further, since the front end surface a (FIG. 3) of the coil bobbin 17 and the front end surface b of the cover 18 are formed as slopes that are inclined in opposite directions to each other, when the caulking piece 19 is caulked, the slopes a, b Are engaged with each other to further firmly fix the electromagnetic coil 4, and the electromagnetic coil 4 is completely closed to the outside world. Also, the coil bobbin
The annular groove 17A of 17 and the annular groove 18A of the cover 18 are both formed into a regular octagon, and the electromagnetic coils 4 inserted into these grooves 17A and 18A are also formed into a regular octagon of substantially the same size. Therefore, when the electromagnetic coil 4 is fitted and housed in the coil bobbin 17 and the annular grooves 17A and 18A of the cover 18, these three members are integrally connected, and thus the relative vibrations of these coils can be obtained without injecting the impregnated varnish. , Rotation is blocked.

In this case, in this embodiment, the annular groove 17A of the coil bobbin 17 is
And the annular groove 18A of the cover 18 are both formed into a regular octagon, but at least one of them may be formed into a regular octagon, and the shape is not limited to a regular octagon, and may be a hexagon, a hexagon, or the like. The electromagnetic coil 4 may be formed in a polygonal shape so as to match this. Further, the electromagnetic coil 4 is not a self-bonding copper wire that is hardened in advance with a bond wire, but is a copper wire having a general insulating coating, and is an electromagnetic coil that is wound in a polygonal shape and then fixed with an insulating tape. May be.

One terminal in the circumferential direction of the coil bobbin 17 is a terminal box 20 (fourth terminal box) formed in the shape of a substantially rectangular box.
(Fig.) Is integrally formed, and this terminal box 20 protrudes from the hole 2B of the yoke 2 to the outside. The wire 21 at either the winding start or the winding end of the electromagnetic coil 4 is inserted into this terminal box 20. It is inserted and stored. Reference numeral 22 is a concave groove provided to facilitate the insertion. A cover 23 formed in a substantially rectangular box shape longer than the terminal box 20 is capped on the protruding portion of the terminal box 20 from the yoke 2. The cover 23 is ultrasonically welded or bonded by an adhesive agent. Sticked to 20. The wire 21 inserted into the terminal box 20 and the lead wire 5 are connected by the terminal metal fitting 24 in the terminal box 20, and the lead wire 5 is connected to the coil bobbin in the cover 23.
Waterproof rubber bush 2 engaged in groove 20d formed in 17
After being protected by 5, it is pulled out from the concave groove 23a of the cover 23. And, the terminal metal fitting 24 is 2 in the terminal box 20.
It is press-fitted between the wall surfaces 20a and 20b, and its end face is brought into contact with the wall surface 20c so as to be firmly fixed. As a result, the external force applied to the lead wire 5 does not act on the wire 21. Reference numeral 26 is a ground-side terminal fixed to the surface of the yoke 2 by screwing or caulking, to which a ground wire 27 drawn from the coil bobbin 17 is connected.

The operation of the electromagnetic clutch configured as above will be described. When the V-pulley 10 is driven and rotated from the drive source side, the rotor 8 integrated with the V-pulley 10 rotates via the bearing 6 on the nose portion 1a of the housing 1. At this time, when the electromagnetic coil 4 is excited, a magnetic flux is formed from the yoke 2 through the outer pole of the rotor 8 and then to the armature 16 by the action of the demagnetization portion and returns to the yoke 2 through the inner pole of the rotor 8. So armature 16
Is attracted to the rotor 8 against the elastic force of the leaf spring 15. As a result, the armature 16 rotates integrally with the rotor 8, the rotating shaft 11 integral with the armature 16 rotates, and the air compressor operates.

When the excitation of the electromagnetic coil 4 is released, the armature 16 is a leaf spring.
The elastic force of 15 separates from the rotor 8 to release the rotation transmission and stop the rotation of the rotating shaft 11.

In such an electromagnetic clutch, when the electromagnetic coil 4 is incorporated in the yoke 2, the electromagnetic coil 4 previously hardened with a bond wire is housed in the coil bobbin 17 and the wire 21 is inserted.
After pulling out the ground wire 27 and the ground wire 27, the coil bobbin 17 is inserted into the annular groove 3 of the yoke 2 with its opening end in the same direction. Then, when the annular cover 18 is capped on the exposed portion of the electromagnetic coil 4 from the coil bobbin 17, the cylindrical portions 18a and 18b of the cover 18 are separated from the peripheral surface of the electromagnetic coil 4 and the annular groove 3.
The coil bobbin 17 is fixed by press-fitting with the inner peripheral surface of the coil bobbin 17, but when the crimping piece 19 is further bent and crimped, the coil bobbin 17 is firmly fixed in a state of being prevented from coming off.
During caulking, the inclined surface a at the tip of the coil bobbin 17 and the inclined surface b at the end of the cover 18 bite into each other, so that the coil bobbin 17 is more firmly fixed, and the electromagnetic coil 4 is completely blocked from the outside. Moreover, since the electromagnetic coil 4 is formed in a regular octagon, and is fitted in the regular octagonal coil bobbin 17 and the annular grooves 17A, 18A of the cover 18, which can be rotated by vibration or the like. Without
There is no need to fix with impregnated varnish or the like as in the past.

Next, the wire 21 drawn into the terminal box 20 and the external lead wire 5 are connected by the terminal fitting 24, and the terminal fitting 24
Is press-fitted between the two wall surfaces 20a and 20b in the terminal box 20, the end surface of the terminal box 20 is brought into contact with the wall surface 20c of the terminal box 20, and the rubber bush 25 is engaged with the groove 20d. To connect to the power supply. As a result, the end surface of the terminal fitting 24 abuts and is fixed to the wall surface 20c, so that the lead wire 5
Even if an external force is applied to the wire 21, it does not reach the wire 21 or the like. Also in this case, there is no need to inject resin or the like into the terminal box 20 as in the conventional case. By connecting the ground wire 27 to the ground terminal 26, the mounting work of the electromagnetic coil 4 is completed.

[Advantages of the Invention] As described above, according to the electromagnetic coupling device of the present invention, the electromagnetic coil is wound in a polygonal shape, and the annular groove of at least one of the coil bobbin for accommodating the electromagnetic coil and the cover is formed in the electromagnetic coil. Since it is formed in a polygonal shape, the electromagnetic coil can be securely fixed without being filled with the impregnated varnish as in the conventional case, and its rotation and the disconnection accident of the coil can be prevented. It can be installed easily and in a short time, improving productivity and reducing labor.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment in which the electromagnetic coupling device according to the present invention is applied to an electromagnetic clutch for a compressor of a car cooler, FIG. 2 is a front view of a yoke, and FIG. 3 is an enlargement of an electromagnetic coil storage portion. A sectional view and FIG. 4 are sectional views taken along line IV-IV in FIG. 2 ... Yoke, 3 ... Annular groove, 4 ... Electromagnetic coil, 5 ...
… Lead wire, 17 …… Coil bobbin, 17A …… Annular groove, 18
...... Cover, 18A ...... annular groove, 19 ...... Crimping piece.

Claims (1)

[Scope of utility model registration request] 1. A yoke having an annular groove, and an electromagnetic coil, which is formed in an annular shape having a U-shaped cross section, and which is previously wound in a polygonal shape, is housed in a state in which a substantially half portion is exposed. A coil bobbin inserted into the annular groove of the coil bobbin with its opening side oriented in the same direction as the coil bobbin and having a U-shaped cross-section, and opening to the opening side of the coil bobbin and protruding from the coil bobbin of the electromagnetic coil. And a cover press-fitted into the annular groove of the yoke, the cover being fixed in the yoke by partially caulking the opening end of the yoke, and the coil bobbin and the At least one of the annular grooves formed in the cover is a polygonal annular groove that matches the shape of the peripheral surface of the electromagnetic coil having a polygonal shape.