JPS6231213B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in electromagnets for electromagnetic clutches. Fig. 1 shows a conventional electromagnetic clutch, which includes a rotor 1 fitted in a bearing 3, a leaf spring 8 which is arranged with a gap facing the end face of the rotor 1 and has elasticity in the axial direction, and a load machine. The armature 5 is engaged with the fixed hub 4 by a rivet 6,
The rotor 1 includes an electromagnet 2 housed in an annular groove having a U-shaped cross section. In the above configuration, when the rotor 1 is rotating due to external power, the electromagnet 2 is energized, and magnetic flux is generated in the magnetic path composed of the rotor 1, the armature 5, and the electromagnet 2, and the armature 5 is rotated by the leaf spring. The rotation is transmitted by the hub 4 which is attracted to the end surface of the rotor 1 against the load of 8 and is engaged with the leaf spring 8.

2 and 3 show the configuration of a conventional electromagnet 2, which includes a flange 9 fixed to a load machine, a yoke 10 for forming a magnetic path, and a coil 12 that also serves as a part of this yoke 10. An annular casing 11 having a U-shaped cross section for accommodating the coil is fixed together, the coil is housed therein, and resin is filled. In the conventional example described above, the housing 11 is formed by press working, but
Due to the influence of variations in the thickness of the steel plate used as the material, the draft angle of the drawing die, the spring back of the material, etc., it is necessary to ensure the accuracy of the roundness, cylindricity, and centrality of the inner and outer cylinders, and the flatness of the bottom. is extremely difficult, and
The coil 12, which is separately wound and whose outer periphery is taped with an insulating tape 15, is stored in a state in which an allowance is made in the internal volume of the coil storage portion of the casing 11 to facilitate resin filling. Since the clutch is located at the bottom of the casing, it has the disadvantage of falling down, and the electromagnet 2 has been the main factor preventing the overall clutch from becoming more compact.

The present invention has been made in view of the drawbacks of the conventional example, and embodiments of the present invention will be described with reference to FIGS. 4 to 7. Note that explanations of parts common to those of the conventional example will be omitted, and the same numbers will be used for the same parts. An insulator 19 for electrical insulation from the coil 12 is coated on the outer peripheral surface of the electromagnetic cylinder 21 having an L-shaped cross section as shown in FIG.
After the connection of the lead wire 13 of No. 2 is completed, the exposed creeping surface of the coil 12 and the creeping portion of the opposite side to the yoke 10 are covered with a fixing material 2 such as varnish, paint, resin, etc.
0 to form an insulating layer that also serves as an outer cover. 22 is an insulating bushing. FIG. 5 shows a method of winding the coil 12 directly around the electromagnetic cylinder 21 coated with the insulator 19. The self-fused wire is wound around the electromagnetic cylinder 21 which is fixed to the shaft 23 of the winding machine with side plates 24 and 25. A wound coil 12 is formed, and lead wires 17 are provided at both ends of the winding.
In this configuration, the yoke 10 shown in FIG. 6 is press-fitted and fixed from the connected state. Figure 4 is shown in yoke 10.
A lead wire storage section 26 and a lead wire lead-out notch 27 shown in FIGS. 6 and 7 are provided to facilitate drawing out the lead wire.

According to the embodiment with the above configuration, the conventional case 11
By using the electromagnetic cylinder 21 instead of
Not only is it free from the difficulty of drawing and forming, but the outer diameter of the electromagnet can be significantly reduced without requiring a long time for resin filling.

In addition, since the coil 12 is directly wound around the insulator 19 coated on the electromagnetic cylinder 21, the space factor of the coil storage area is significantly improved, and the coating that covers the exposed surface of the coil 12 is also formed into an extremely thin film. It can be processed in a very short time by spraying, dipping, heat-shrinking tubes, etc., resulting in a large saving in the amount of materials used.

Furthermore, by providing the lead wire lead-out notch 27 in the yoke 10, when the yoke 10 is press-fitted into the electromagnetic cylinder 21, it is difficult to take out the lead wire 17 through the through hole as in the conventional example. It can be easily attached from the outer circumference of the yoke 10 without any need for the yoke.

As described above, the present invention has the following unique effects.

(1) To form a coil with self-fused wire,
Mechanical coil shape retention means are not required;
Miniaturization can be achieved.

(2) By providing a notch that penetrates the yoke and draws out the lead wire, it becomes easier to pull out the lead wire, connect the lead wire, etc., and it does not become difficult due to thickening of the coil. .

(3) Since the yoke part has a lead wire storage groove, it can be shortened in the length direction, and miniaturization can also be achieved in this respect.

[Brief explanation of the drawing]

Figure 1 is a sectional view of a conventional electromagnetic clutch, Figure 2 is a sectional view of a conventional electromagnetic clutch.
3 is a perspective view showing the configuration of the coil in FIG. 1, FIG. 4 is a partial sectional view of the electromagnet according to the embodiment of the present invention, and FIG. FIG. 6 is a cross-sectional view showing a method of winding an electromagnet coil according to an embodiment of the present invention, FIG. 6 is a perspective view showing the structure of the electromagnet according to the present invention, and FIG. 7 is a plan view of the yoke. 1... Rotor, 2... Electromagnet, 3... Bearing,
5... Armature, 10... Yoke, 12... Coil, 27... Notch for leading out lead wire.

Claims (1)

[Claims] 1. In an electromagnet of an electromagnetic clutch housed in an annular rotor that is rotatably supported by a bearing and has a groove having a substantially U-shaped cross section with an armature disposed opposite the end face, the electromagnet is located close to the inner cylindrical portion that constitutes the groove. An insulating layer is formed on the outer periphery of the electromagnetic cylinders arranged facing each other by coating or adhering, and a coil made of self-fused wire is directly wound on the insulating layer, and a magnetic path is formed with the electromagnetic cylinder. and an annular yoke having a lead wire storage groove is provided opposite to the coil, and an insulating layer that also serves as an outer covering that covers the creeping surface of the coil and a portion of the yoke facing the coil, An electromagnet for an electromagnetic clutch, wherein the yoke is provided with a notch for taking out the lead wire of the coil from the end of the coil through the yoke.