JPH0237268Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field of the Invention The present invention relates to an improvement in the magnetic pole structure of a small electric motor.

Prior Art In a small electric motor 1 of this type, as shown in FIG. The core 3 and the base plate 5 form a gear train chamber 6.
A rotatable rotor 7 is provided in the bobbin storage chamber 4.
A bobbin 9 on which an excitation winding 8 is wound is housed. A magnetic pole 10 bent from a desired position of the stator 2 and core 3 is interposed between the rotor 7 and the bobbin 9. Further, the gear train chamber 6 accommodates a gear train 14 that transmits the rotation of the rotor 7 to the output shaft 11 via a plurality of gears.

By the way, the conventional stator 2 is shown in FIGS. 2 and 3.
As shown in the figure, the magnetic pole 10 is a conformal pole 10a.
and an asymmetrical pole 10b. This unequal angle pole 1
0b determines the forward and reverse rotation directions of the rotor 7, and includes an unequal angle pole 10b for forward rotation (clockwise) shown in FIG. 2 and an unequal angle pole 10b for reverse rotation (counterclockwise) shown in FIG. The asymmetrical pole 10b is shifted by a predetermined angle to either side with the quarter line of the central angle as the boundary.

Therefore, depending on whether the stator 2 is for forward rotation or reverse rotation, the stator 2 must be separately pressed. Therefore, a press die for forward rotation and a press die for reverse rotation must be prepared separately, which poses a problem in that the manufacturing cost of this type of small electric motor increases.

Purpose of the invention Therefore, the purpose of the present invention is to construct a stator with a special shape and to create a compact stator that can be used for both forward rotation and reverse rotation by forming the stator into a single press die. Our goal is to provide electric motors.

Summary of the invention Therefore, the present invention forms a plurality of magnetic poles so that they can be bent radially within a magnetic pole forming hole drilled in the stator, and the plurality of magnetic poles lie on isometric lines except for at least two magnetic poles. and the at least two magnetic poles are provided as asymmetrical poles shifted in different rotational directions with respect to the isometric line,
The structure is such that one of the at least two magnetic poles is selectively bent depending on the specification of the rotation direction. With such a magnetic pole configuration, both forward and reverse stators can be punched out using one common press die, and the manufacturing cost of this type of small electric motor can be reduced.

Embodiment Hereinafter, a small electric motor of the present invention will be explained based on an embodiment shown in FIGS. 4 to 6.

4 and 5 show the magnetic pole configuration of the stator 2 used in the small electric motor 1 of the present invention. That is, on the bottom surface of the stator 2, a pair of equiangular poles 10a are arranged on one of the quarter lines of the central angle.
are formed to face each other, and the pair of axonometric poles 10b for forward rotation and the pair of axonometric poles 10b for reverse rotation are deviated from each other with the other line as the boundary, and are pressed, etc. It is formed by
When this stator 2 is used for normal rotation, as shown in FIG.
The non-conformal pole 10b for forward rotation is bent approximately at right angles. On the other hand, when the stator 2 is used for reverse rotation, as shown in FIG.
The asymmetrical pole 10b for reversal is bent.

Therefore, according to the user's request, one of the non-conformal poles 10b for normal rotation and reverse rotation is selectively bent in a substantially right-angled direction, and the non-conformal poles 10b and the non-conformal poles 10a are bent. Rotor 7 inside bent stator 2
and bobbin 9 are accommodated.

By the way, as shown in FIG. 1, the stator 2 accommodates a rotor 7 and a bobbin 9.
As shown in FIG. 6, the magnetic pole forming hole 12 of the magnetic pole 10
A protrusion 13 is formed on the collar 9a of the bobbin 9 facing the magnetic pole forming hole 12.
is mated to. The portion of this convex portion 13 that faces the non-conformal pole 10b is formed as a groove, so that the non-conformal non-conformal pole 10b is formed as a groove.
is fitted into the groove.

Therefore, when housing the bobbin 9 in the stator 2, the protrusion 13 provided on the collar 9a of the bobbin 9
The bobbin 9 can be easily positioned with respect to the stator 2 by fitting into the magnetic pole forming holes 12 of the equiangular poles 10a and the asymmetrical poles 10b. Moreover, since the non-conforming non-conformal pole 10b also fits into the groove of the convex portion 13, it plays the role of positioning the bobbin 9 and preventing it from rotating.

Effects of the invention In this invention, the stator is provided with at least one axonometric pole for forward rotation and one for reverse rotation, and according to specifications,
The structure is such that either one of the asymmetric poles is bent selectively. Therefore, it is possible to punch out a stator for forward rotation and reverse rotation using a single press die, which makes it possible to reduce the manufacturing cost of this type of small electric motor. .

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a small electric motor, Fig. 2 is a plan view of a conventional stator for forward rotation, Fig. 3 is a plan view of a conventional stator for reverse rotation, and Fig. 4 is a state in which the stator according to the present invention is used for forward rotation. 5 is a plan view showing a state in which the stator of the present invention is used for reverse rotation, and FIG. 6 is a bottom view showing a state in which the stator and bobbin are fitted. DESCRIPTION OF SYMBOLS 1...Small electric motor, 2...Stator, 3...Core, 4...Bobbin storage chamber, 5...Main plate, 6...Gear train chamber, 7...Rotor, 8...Winding, 9...Bobbin , 9a...Brim, 10...Magnetic pole, 10a...Conformal pole, 10b...Asymmetrical pole, 11...Output shaft, 12...Magnetic pole forming hole, 13...Convex portion.

Claims (1)

[Scope of utility model registration request] In a small electric motor comprising a magnetic pole forming hole drilled in a stator, a plurality of magnetic poles formed in the magnetic pole forming hole and arranged radially, and a rotor disposed opposite to the bent magnetic poles. , at least two of the plurality of magnetic poles are bendably provided as anomalous poles with different deviation directions from the equiangular pole position. A small electric motor characterized by having one of the parts selectively bent and facing the rotor.