JP2001339894A - Motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make assembling work easy for a motor. SOLUTION: In the motor, a resin-molded spool 1 is mounted at a stator core 6 for providing electrical insulation between the stator core 6 and a winding 8. The motor includes a bushing 3 molded with resin in a body with the spool 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electric motor having a bushing.

[0002]

2. Description of the Related Art An embodiment of a conventional motor will be described with reference to FIGS. FIG. 4 is a front view of a conventional stator. FIG. 5 is a front view when a lead wire with a bushing is attached to a circuit board. FIG.
FIG. 5 is an enlarged partial side sectional view when a circuit board is attached to the stator of FIG. 4. FIG. 7 is a side sectional view of an electric motor using the stator of FIG.

In FIG. 4, a stator 21 is formed of a back yoke 22 formed in a cylindrical shape and a plurality of teeth 23 extending from the inner peripheral portion of the back yoke 22 toward the axial center. Stator core 24 and stator core 2
4, a winding 25 wound around each tooth 23,
A resin-molded spool 26 is attached to the stator core 24 to electrically insulate the stator core 24 and the winding 25 from each other.
It is composed of

[0005] In FIGS. 5 and 6, a circuit board 27 is attached to one end face of the stator 21. On the circuit board 27, a pattern for connecting the windings 25 is provided, or a Hall IC 28 or the like for detecting the number of rotations is mounted.

[0005] The bushing 29 is composed of two pieces 30, 31, and is formed in a rectangular shape. Each of the pieces 30 and 31 is provided with a semicircular groove corresponding to the number of the lead wires 32 for accommodating the lead wires 32. The lead wire 32 is mounted in the bushing 29 by arranging the lead wire 32 in the groove and holding the lead wire 32 between the pieces 30 and 31. One piece 30 is provided with a projection 30a for attaching and fixing the bushing 29 to the circuit board 27.

A lead wire 32 is attached to the circuit board 27 by soldering. In addition, one piece 3
The zero protrusion 30a is inserted into and attached to the hole 27a provided in the circuit board 27 and fixed.

Therefore, the lead wire 32 is fixed to the stator 21 via the circuit board 27 because it is mounted in the bushing 29. In FIG. 7, the electric motor 33 includes a stator 21, a lead wire 32 attached to the stator 21, a circuit board 27, and a lead wire 32.
, A rotor 34 housed on the inner peripheral surface of the stator 21, and two bearings 3 mounted on both ends of the rotor 34 to make the rotor 34 rotatable.
5a, 35b, a bearing bracket 36 accommodating and fixing one bearing 35a, a stator 21, a circuit board 27
And a storage portion 37 for storing the other bearing 35b
a, and a motor frame 37 molded with a mold resin 38 to which a bearing bracket 36 is attached.

A part of the bushing 29 is built in the motor frame 37, and the remaining part is provided so as to protrude outside the motor frame 37.

[0009]

In a conventional motor with a bushing, the bushing is fixedly attached to a circuit board, but is not securely attached.
Also, the circuit board is not securely attached to the stator.

That is, it is difficult to reliably fix the position of the bushing, and the bushing is easily displaced by an external force.

[0011]

According to the present invention, there is provided a resin-molded spool mounted on a stator core and electrically insulating the stator core from the windings, and integrally formed with the spool. An electric motor comprising a resin-molded bushing.

[0012]

The number of components can be reduced by integrally molding a resin-molded spool that insulates the stator core from the winding and a bushing that protects the lead wire.
Since the bushing is securely fixed, the assemblability of the electric motor can be improved.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a motor with a bushing according to the present invention will be described with reference to FIGS. 1 to 3 taking a brushless DC motor as an example. FIG. 1 is a front view of a spool with a bushing according to the present invention. FIG. 2 is a front view of the stator when the lead wires are arranged on the bushing. FIG. 3 is a side sectional view of an electric motor using the stator of FIG.

In FIG. 1, the spool 1 is formed by resin molding. Further, the stator core has a two-piece configuration, and each piece is attached so as to sandwich the stator core from both end surfaces of the stator core. With such a configuration, insulation between the stator core and the winding is enabled.

Also, one piece 2 of the spool 1 has
The lower base of the bushing 3 is integrally formed so as to be formed in a direction perpendicular to the axis of the stator.

The bushing 3 is provided with semi-circular grooves 3a corresponding to the number of the lead wires for disposing the lead wires. At the end of the bushing 3, a hole 3b for attaching the upper base of the bushing is provided.

Referring to FIG. 2, a stator 4 includes a stator core 6
And a winding 8 wound around the teeth 7 of the stator core 6
And the spool 1 attached so as to cover the stator core 6.

A circuit board 10 to which a plurality of lead wires 9 are attached is attached to one end face of the stator 4. The lead wires 9 are respectively provided in the grooves 3 a on the lower stage of the bushing 3.

The lead wire 9 is sandwiched by overlapping an upper base (not shown) of the bushing 3 having a groove having the same shape as that of the lower base of the bushing 3 with a lower base.

In FIG. 3, the motor 11 comprises a stator 4, a lead wire 9 attached to the stator 4, a circuit board 10, and a bushing integrally formed on the spool 1, as in the conventional motor. 3, a rotor 12 housed on the inner peripheral surface of the stator 4, and two bearings 13a attached to both ends of the rotor 12 to make the rotor 12 rotatable;
13b, a bearing bracket 14 that houses and fixes one bearing 13a, and a housing 15a that houses the stator 4 and the circuit board 10 and houses the other bearing 13b. The motor frame 15 is formed of resin 16.

A part of the bushing 3 is built in the motor frame 15 and the other part is the motor frame 1.
5 protruding outside.

With the above configuration, the bushing can be fixed securely, and the workability of assembly is improved.
For example, when the stator to which the lead wire and the circuit board are attached is set in the mold and the bushing is stored in the bush storage section of the mold, the bushing position is determined with respect to the stator. There is no need to adjust the position and store it in the storage unit.

[0023]

According to the present invention, there is no need to fix the bushing when assembling the electric motor, and the assembling work can be easily performed. Also, the number of parts can be reduced.

[0024]

[Brief description of the drawings]

FIG. 1 is a front view of a spool with a bushing according to the present invention.

FIG. 2 is a front view of a stator when a lead wire is arranged on a bushing.

FIG. 3 is a side sectional view of an electric motor using the stator of FIG. 2;

FIG. 4 is a front view of a conventional stator.

FIG. 5 is a front view when a lead wire with a bushing is attached to the circuit board.

FIG. 6 is an enlarged partial side sectional view when a circuit board is attached to the stator of FIG. 4;

FIG. 7 is a side sectional view of an electric motor using the stator of FIG. 5;

[Explanation of symbols]

 1, 26 ... Spool 2, 30, 31 ... Piece 3, 29 ... Bushing 4, 21 ... Stator 6, 24 ... Stator core 7, 23 ... Teeth 8, 25 ... Winding 9, 32 ... Lead wire 10, 27 ... Circuit boards 11, 33 ... Electric motors 12, 34 ... Rotors 13a, 13b, 35a, 35b ... Bearings 14, 36 ... Bearing brackets 15, 37 ... Motor frame 22 ... Back yoke 28 ... Hall IC

Claims (1)

[Claims] An electric motor having a bushing for protecting a lead wire when the lead wire is drawn out of the motor frame. The electric motor is mounted on a stator core and electrically connected to a stator core and a winding. An electric motor, comprising: a resin-molded spool for insulation; and a bushing resin-molded integrally with the spool.