JPH0315865Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to electromagnetic coupling devices such as electromagnetic clutches and electromagnetic brakes.

[Conventional technology]

Conventionally, among this type of electromagnetic coupling device, the one shown in FIG. 2 has been adopted as an example of an electromagnetic clutch, and this will be briefly explained based on the same figure. In the figure, 1 is a driven shaft; 2 is a rotor fixed to the driven shaft 1 with a key 3; 4 is a lining provided on the rotor 2; 5 is a hub loosely fitted to the driven shaft 1 so as to be relatively rotatable; 6 is the hub 5. It is rotated by a drive source (not shown) by a gear formed on the outer periphery of the motor. Reference numeral 7 denotes an armature that faces the lining 4 via a gap g and is supported non-rotatably on the hub 5 via a leaf spring 8, and is provided so as to be movable in the axial direction by the elasticity of the leaf spring 8. . 9 is an annular yoke that is relatively rotatably supported by the rotor 2 via a metal 10; 9a is an annular groove formed in this yoke 9; 9b is a draw-out hole that communicates with and penetrates this groove 9a; Reference numeral 11 denotes an annular excitation coil installed in the groove 9a, and its magnetic flux is indicated by Φ in the figure. Reference numeral 12 denotes a bobbin around which the excitation coil is wound, and has a knurled portion 12a on its inner peripheral portion, and is fixed to the groove portion 9a by the knurled portion 12a so as not to be movable in the rotational and axial directions. Reference numeral 13 denotes a lead wire of the excitation coil, which is led out from the lead-out hole 9b and connected to a power source (not shown). Reference numeral 14 denotes a grommet attached to the pull-out hole 9b, and the lead wire 13 passes through the grommet 14.

Next, the operation will be explained. When the excitation coil 11 is energized, a magnetic flux Φ is generated, a magnetic circuit is formed, and the armature 7 is magnetically attracted to the rotor 2 against the elastic force of the leaf spring 8. Therefore, the rotational force of the drive source (not shown) is transmitted to the driven shaft 1 via the gear 6, hub 5, leaf spring 8, armature 7, lining 4, rotor 2, and key 3, and the driven shaft 1 rotates. be done. Furthermore, when the excitation coil 11 is de-energized, the magnetic flux Φ disappears, and the armature 7 is separated from the rotor 2 by the elastic force of the leaf spring 8 and faces the rotor 2 via the gap g. The transmission path of the rotational force is cut off, and the lining 4, the rotor 2,
The key 3 and driven shaft 1 stop.

Here, when the rotor 2 rotates when the excitation coil 11 is energized, a slight rotational force acts on the yoke 9 via the metal 10, but this rotational force is received by a rotation prevention holder (not shown). , rotation of the yoke 9 is prevented.

[Problem that the invention attempts to solve]

In the conventional electromagnetic coupling device as described above, the bobbin 12 and the yoke 9 are connected to the groove 9a of the knurled portion 12a.
Although it is fixed by press fitting into the bobbin 12
Since it is made of synthetic resin, the dimensions of the knurling part become large due to thermal expansion, moisture absorption, etc., and the groove part 9a
The press-fitting allowance is small. For this reason, a predetermined holding force between the bobbin 12 and the yoke 9 cannot be obtained, and the bobbin 12 becomes movable in the axial and rotational directions, which interferes with the rotor 2 and breaks the lead wire 13 due to this interference, making it inoperable. There was a problem with the lack of reliability.

In addition, when press-fitting the bobbin 12 into the yoke 9, it is difficult to align the lead wire 13 with the lead wire 9b. There was a problem in that the coating of the lead wire 13 was peeled off, resulting in poor withstand voltage.

In addition, it is necessary to insert and fix the grommet 14 into the pull-out hole 9b in order to insulate the yoke 9 and the lead wire 13, which, together with the press-fitting of the bobbin 12, causes problems such as poor workability and low productivity. Ta.

This idea was created to solve the problems mentioned above. It not only allows the bobbin to be securely held in the yoke, but also prevents the lead wire from getting caught in the pull-out hole, resulting in high reliability and improved productivity. The purpose of this invention is to obtain an electromagnetic coupling device with excellent performance.

[Means to solve the problem]

The electromagnetic coupling device according to this invention includes an insulating cylinder inserted into a pull-out hole of a yoke, and locking parts provided at both ends of the insulating cylinder and each latched in the axial direction at the bottom of a groove in the yoke. is formed integrally with the bobbin.

[Effect]

In this invention, since the bobbin is locked in the axial direction by the locking portion, there is no reduction in holding force due to expansion of the bobbin as in the conventional case, and the bobbin is completely fixed. In addition, alignment of the yoke and the bobbin when passing the lead wire through is facilitated, improving work efficiency, and the lead wire is not caught in the lead wire, thereby preventing breakdown voltage failure.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, reference numeral 12b is an insulating cylinder inserted into the draw-out hole 9b and formed integrally with the bobbin 12. 12c and 12d are formed integrally with the bobbin 12 and the insulating cylinder 12b at both ends of the insulating cylinder 12b, and at the bottom 9c of the groove 9a of the yoke 9,
Each of the locking portions is locked in the axial direction, and the locking portion 12c on the distal end side is tapered so that it can be inserted into the pull-out hole. The rest of the configuration is the same as the conventional device, so the explanation thereof will be omitted.

In the structure as described above, since the bobbin 12 and the locking parts 12c and 12d are integrally formed and fixed by sandwiching the bottom part 9c of the yoke 9, there is no reduction in holding force due to expansion of the bobbin 12. , the yoke 9 and the bobbin 12 are securely fixed.
Further, since the bobbin 12 and the insulating cylinder 12b are integrally formed, the lead wire 13 is prevented from being caught when the lead wire 13 is passed through the extraction hole 9b. Further, when inserting the bobbin 12 into the yoke 9, the locking portion 12c serves as a guide, making it easy to align the yoke 9 and the bobbin 12, improving work efficiency. Furthermore, the conventional grommet 14 is no longer necessary, and the number of parts is reduced.

[Effect of idea]

As described above, according to this invention, there is an insulating tube that is inserted through the leet wire pull-out hole of the yoke, and a lock that is provided at both ends of the insulating tube and that is axially locked at the bottom of the yoke groove. Since the part is formed integrally with the bobbin, it is possible to securely fix the bobbin and yoke, and it also prevents voltage resistance failures due to lead wires being caught, resulting in high reliability. Positioning at the time of insertion is facilitated, and an electromagnetic coupling device with excellent productivity can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a partial sectional view showing an electromagnetic coupling device according to an embodiment of the invention, and FIG. 2 is a partial sectional view showing a conventional device. In the figure, 2 is the rotor, 7 is the amateur, and 9
9a is a yoke, 9a is a groove, 9b is a draw-out hole, 9c is a bottom, 11 is an excitation coil, 12 is a bobbin, 12b is an insulating tube, 12c and 12d are locking portions, and 13 is a lead wire. In each figure, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] A yoke having an annular groove in which a bobbin of an excitation coil is housed, and a draw-out hole that communicates with the groove and penetrates in the axial direction, an insulating tube inserted through the draw-out hole; Locking portions provided at both ends of the cylinder and locked to the yoke are integrally formed with the bobbin, and the lead wire of the coil is led out from the insulating tube, and the locking portions are connected to the bobbin. An electromagnetic coupling device, characterized in that: is fixed to the yoke.