JPH055828Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a small synchronous motor with reinforced electrical insulation of a coil bobbin.

[Prior art]

Conventionally, as shown in FIG. 6, a coil bobbin 3 of a small synchronous motor has circular flanges 3b and 3c on both sides, and a winding 11 is wound therebetween, covering the coil bobbin 3 so as to span between the circular coil bobbin and both flanges. A cylindrical insulating cover 8 is fitted from one side of the flange 3b, and the vinyl-coated lead wire 1 is inserted as shown in FIG.
3 and 13 are fitted into the grooves of the flange, and the side to be connected to the end wire of the winding is bent toward the winding at the notches 3e, 3e and connected to the end wire, and this coil bobbin has pole teeth on both sides. It was housed in cases 1 and 2.

When current is passed through the winding, the vinyl coating melts due to heat generation, and the core wire of the lead wire 13 is exposed for a long time as shown in FIG. Since the insulation distance between the winding and the case 2 is not sufficient, there is a drawback that moisture enters after the moisture resistance test and the insulation performance deteriorates significantly. Furthermore, since the distance between the winding 11 and the case 2 is short at the notch 3e in the dielectric strength test, there is a drawback that insulation failure is likely to occur.

[Purpose of invention]

SUMMARY OF THE INVENTION In view of the above-mentioned drawbacks, the present invention provides a small synchronous motor with a simple structure and enhanced insulation between the windings of a coil bobbin and a magnetic metal case.

[Structure of the idea]

The present invention provides a circular coil bobbin with circular flanges on both sides and a wire wound therebetween between opposed metal cases with pole teeth formed thereon. It has a cylindrical insulating cover, and a circular insulating plate having the same shape and having a diameter equal to or larger than the outer diameter of the flange is provided between the metal case and the coil bobbin.

[Example] The present invention will be explained below with reference to the illustrated example. In Fig. 1, a small synchronous motor is constructed by combining left and right magnetic metal cases 1 and 2, in which a circular coil bobbin 3 is housed, and bearings 4 and 5 are fixed to the cases 1 and 2, respectively, to drive the rotor. The shaft 6 is supported,
A rotor 7 is fixed to a rotor shaft 6.

In the cases 1 and 2, pole teeth 1a and 2a are cut and raised, respectively, and the pole teeth 1a and 2a are arranged in an alternate combination, and sizing coils 10 and 10 are fitted into the roots of the pole teeth 1a and 2a, respectively. The coil bobbin 3 is held in a groove-shaped recess 3a shown in FIG.

The circular coil bobbin 3 has circular flanges 3b and 3c formed on both sides, and the winding wire 11 is wound therebetween, and a cylindrical insulating cover 8 covering the coil bobbin 3 extends between the flanges 3b and 3c on one side. The insulating cover is fitted from the side of the flange 3b, and both the flange parts and the insulating cover are in contact with each other. As shown in FIGS. 1 and 2, between the flanges 3b and 3c and the cases 1 and 2, both the insulating cover on the cylinder and the coil bobbin each have a diameter larger than the contact surface with the flanges. , circular insulating plates 12, 12 made of polyester film or the like having the same shape are inserted to cover the contact surfaces.

As shown in FIG. 3, two arc-shaped grooves 3d, 3d and notches 3e, 3e are formed in the flange 3b, into which two vinyl-coated lead wires 13 are fitted,
One end of the lead wire 13 is connected to the winding 11 at the notch 3e.
It is bent to the side and connected to the end wire of the winding 11.

A magnet 14 which is magnetized with multiple poles in the circumferential direction is fixed to the outer periphery of the rotor 7, and an output gear 15 is fixed to one end of the rotor shaft 6.

When the small synchronous motor is configured as described above,
The space between both sides of the coil bobbin 3 and the cases 1 and 2 has a diameter larger than the contact surface between the cylindrical insulating cover and the flanges 3b and 3c provided on both sides of the coil bobbin, and the contact surface Since the circular insulating plates 12, 12 of the same shape are inserted, the winding 11 and the cases 1, 2 are isolated by the insulating plates 12, 12, and the insulation is strengthened. The insulation distance between the winding 11 and the case 1 has been improved by about 25% in the dielectric strength test, and the insulation distance between the case 2 and the flange 3c is longer and moisture does not enter the winding side, so the humidity is 90 to 95%, for example, 40%. ℃
Even after a humidity test of 168 hours, the insulation performance is significantly improved and insulation defects are prevented.

Furthermore, if the insulating plates 12, 12 to be inserted on both sides have the same size, there is no need to select them on the assembly line, making assembly easier, and if the insulating plates 12, 12 are shaped like a ring, the directionality can be eliminated when inserting. This makes assembly work easier.

Figures 4 and 5 show other embodiments of a small synchronous motor with a substantially rectangular outer shape, in which a coil bobbin 3 sandwiched between insulating plates 12, 12 is placed on one side of the cases 1 and 2, and the coil bobbin 3 is placed on the other side. Pole teeth 1a, 2a and rotor 7
is located. A magnetic core material 16 is passed through the center of the coil bobbin 3, and the through holes 1b and 2b of the cases 1 and 2 are inserted into the coil bobbin 3.
A frame 9 made of synthetic resin is fitted to the outside of the pole teeth 1a, 2a, and the saging coil 10,
10 is held, and the frame 9 is connected to the pin 9a and cases 1 and 2.
It is positioned by the through hole.

In this embodiment, the shape of the coil bobbin 3 may be circular or square, and the insulating plates 12, 12
The coil bobbin 3 is also formed to match the coil bobbin 3.

[Effect of idea]

As described above, the present invention provides a small synchronous motor with a simple structure in which a circular insulating cover has a diameter larger than the contact surface between the circular insulating cover and the flanges provided on both sides of the circular coil bobbin, and which has the same shape as the flanges that cover the contact surfaces, is overlapped and inserted into the case. This extends the insulation distance between the case and the windings, and moisture does not enter the windings during moisture resistance tests, thereby significantly improving the insulation performance after the test and improving the insulation voltage. This provides a small synchronous motor with excellent practical effects.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; Fig. 1 is a cross-sectional side view of a small synchronous motor, Fig. 2 is a cross-sectional side view of the disassembled main parts of the small synchronous motor, and Fig. 3 is one case, coil bobbin, and insulating cover. Fig. 4 is a cross-sectional plan view of a small synchronous motor of another shape, Fig. 5 is a cross-sectional side view of the same, Fig. 6 is a cross-sectional side view of main parts of a conventional small synchronous motor, and Fig. 7 is a lead FIG. 3 is a cross-sectional side view showing a state in which the vinyl coating of the wire is melted. 3...Circular coil bobbin, 3b, 3c...Circular collar, 8...Cylindrical insulation cover, 11...
Winding wire, 12...circular insulating plate.

Claims (1)

[Scope of utility model claims] A circular coil bobbin with circular flanges on both sides and a wire wound therebetween is provided between opposing metal cases with pole teeth formed thereon. It has an insulating cover, and includes circular insulating plates having the same shape and having a diameter equal to or larger than the outer diameter of the flanges provided on both sides of the coil bobbin between the metal case and the coil bobbin. A small synchronous motor.