JP2000134856A - Housing structure of magnet-rotation-type motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate the control of dimensions when laminating a stator and to eliminate the vibration noise of a stator part by providing a plurality of elastic cut and raise parts in the direction of the lamination of the stator at a housing and pinching the stator with the elastic cut and raise part. SOLUTION: A cut and raise part 16 for achieving elasticity in the lamination direction of a bracket 14 presses a first-layer outer stator core 8a in a lower direction due to the elasticity. Similarly, a cut and raise part 17 where one portion of a cup-type case 13 is allowed to be elastic in a lamination direction presses a second-layer outer stator core 8b upward due to its elasticity. In this manner, the first-layer and second-layer stators are securely pinched by the cup-type case 13 and the bracket 14 and hence facilitating the control of each part machining dimension and preventing the vibration and noise of the stator.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a stepping motor, and more particularly to a stepping motor housing structure in which a coil bobbin and a plurality of stator cores are laminated in a motor housing in a rotor axial direction.

[0002]

2. Description of the Related Art A claw-pole type motor having a core formed by punching a metal plate with a sheet metal or the like and standing at a right angle has been proposed. This will be described below with reference to the drawings. FIG. 8 shows the structure of a conventional claw-pole type stepping motor. In FIG. 8, reference numeral 1 denotes a housing of a claw pole type stepping motor. 2 is a cup-shaped case made of a metal material, and 3 is a bracket made of a metal material fitted and fixed to an opening of the cup-shaped case 2,
The bracket 3 and the cup-shaped case 2 form a housing. Reference numeral 4 denotes a fixed shaft implanted at the center of the bottom of the cup-shaped case 2, and reference numeral 5 denotes a rotor having a bearing 6 rotatably supported by the fixed shaft 4 and made of a resin such as polyacetal or polyamide. A gear g is engraved on one end of the rotor 5 (the free end side of the fixed shaft 4), and a ring magnet 7 is formed around the gear g.
Are integrally formed. Numeral 12 denotes a stator having two layers. That is, the first layer is configured as follows. 8 is to punch or cut a central portion of a substantially circular magnetic plate to form a plurality of teeth facing the center,
The outer stator core is formed by bending the teeth in a right angle direction. Reference numeral 9 denotes an inner stator core formed in the same manner as the outer stator core 8. The teeth of the outer stator core 8 and the teeth of the inner stator core 9 face each other, and the plurality of teeth are alternately loosely arranged. Reference numeral 10 denotes a coil bobbin which is inserted into a reel having the outer stator core 8 and the inner stator core.
Coil. Further, a second layer having the same configuration is laminated on the first layer. The rotor and the stator configured as described above are connected to the cup-shaped case 2.
After that, it is held down by the bracket 3.

[0003]

However, in such a conventional method, as described above, the total stacking dimensions of the stators which are stacked and assembled in the housing 1 are set to improve the yield during operation. It is set smaller than the inner dimension of the housing 1. In other words, the housing 1 can be assembled with a certain gap. However, since there is a gap between the inside of the housing 1 and the stator section 12 as described above, the stator section 12 is not restrained. Therefore, when starting the motor,
And free vibration occurs when the rotor rotates. Since this causes a noise, a method of inserting a cushion material into a gap or applying an adhesive has been proposed. However, these methods have a problem that the life of the effect is short because the cushion material is displaced or the adhesive is peeled off.

SUMMARY OF THE INVENTION It is an object of the present invention to facilitate dimensional control in stacking stators without increasing the number of parts, and to ensure vibration of the stator due to an assembly gap between the stator and the housing with a simple structure. It is a solution to noise.

[0005]

In order to solve the above-mentioned problems, according to the first aspect of the present invention, there is provided a magnet rotating type comprising a plurality of stators laminated in a housing comprising a case and a bracket. In the motor, this is achieved by providing a plurality of elastic cut-out portions in the housing in the stacking direction of the stator, and sandwiching the stacked stator by the elastic cut-out portions. In the invention described in claim 2, the cut-and-raised portion is achieved by being provided at a position substantially corresponding to the case and the bracket. According to the third aspect of the present invention, the cut-and-raised portion is achieved by making the tip one of a waveform and a hemispherical shape. According to the invention as set forth in claim 4, the present invention is attained by forming a portion of the stator sandwiched by the cut-and-raised portions as a through hole. According to the fifth aspect of the present invention, it is achieved that the portion of the stator sandwiched between the cut-and-raised portions is a concave portion.

[0006]

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view of an essential part showing a first embodiment of the present invention. 2A is an enlarged sectional view of a portion indicated by A in FIG. 1, FIG. 2B is an enlarged sectional view of a portion indicated by B in FIG. 1, and FIG. Plan view. FIG. 3B is an enlarged cross-sectional view showing a cross section taken along line CC of FIG. 3A. FIG. 4A shows the cup type case 1 of FIG.
FIG. 3 is a plan view for explaining No. 3; FIG. 4 (b) is the same as FIG.
It is an expanded sectional view which shows the DD section.

1 to 4, reference numeral 1 denotes a housing of a claw-pole type stepping motor. Reference numeral 13 denotes a cup-shaped case made of a metal material. Reference numeral 14 denotes a bracket made of a metal material fitted and fixed to an opening of the cup-shaped case 13.
3 together form a housing. Reference numeral 4 denotes a fixed shaft implanted at the center of the bottom of the cup-shaped case 13, and 5 has a bearing 6 rotatably supported by the fixed shaft 4.
The rotor is made of a resin such as polyacetal or polyamide. A gear 15 is engraved on one end (the free end side of the fixed shaft 4) of the rotor 5, and a ring magnet 7 is integrally formed therearound. 12
In this embodiment, a stator is described as an example having two layers. However, it is needless to say that an n-layer may be used.

That is, the first layer is configured as follows. Reference numeral 8 denotes an outer stator core formed by punching or cutting a central portion of a substantially circular magnetic plate to form a plurality of teeth facing the center, and bending the teeth in a perpendicular direction. 9
Is an inner stator core formed in the same manner as the outer stator core 8. The teeth of the outer stator core 8 and the teeth of the inner stator core 9 face each other, and the plurality of teeth are alternately and loosely arranged. Reference numeral 10 denotes a coil bobbin inserted into a reel formed by the outer stator core 8 and the inner stator core, and 11 denotes a coil wound around the coil bobbin 10.

The second layer has the same configuration. Here, the first layer is stacked on the second layer. After the rotor and the stator configured as described above are inserted into the cup-shaped case 13, the rotor and the stator are sandwiched and held between the cup-shaped case 13 and the bracket 14. For simplicity, the components of the first layer are denoted by a after the number, and the corresponding components of the second layer are denoted by b after the same number.

Next, the laminated stator 12 which is a main part of the present invention is housed in the housing 1 and
The point of holding between the bracket 3 and the bracket 14 will be described in detail. In FIG. 2, FIG. 2A is an enlarged sectional view of a portion A in FIG. In FIG. 2A, reference numeral 16 denotes a cut-and-raised portion in which the bracket 14 has elasticity in the stacking direction. The cut-and-raised portion 16 is the outer stator core 8 of the first layer.
a is pressed downward by its elasticity. h1 is a gap between the bracket 14 and the upper surface of the first layer outer stator core 8a. Next, FIG. 2B is an enlarged sectional view of a portion B in FIG. In FIG. 2B, reference numeral 17 denotes a cut-and-raised portion in which a part of the cup-shaped case 13 has elasticity in the stacking direction. 17 presses the outer stator core 8b of the second layer upward by its elasticity. h2 is a gap between the cup-shaped case 13 and the lower surface of the second layer outer stator core 8b. This ensures that the first and second layer stators are sandwiched between the cup-shaped case 13 and the bracket 14.

Next, referring to FIG. 3 and FIG.
And the cut-and-raised portion 16 in the cup-shaped case 13 respectively.
The case in which steps 17 and 17 are provided will be described. FIG. 3 (a)
Has three cut-and-raised portions 16 in the plan view of the bracket 14. FIG. 3B is an enlarged cross-sectional view of a portion C-C in FIG. Since the cut-and-raised portion 16 is generally processed with a thin iron-based metal plate, it can be easily made elastic. h3 is the height of the cut and raised portion 16. FIG. 4A is a plan view of only the cup-shaped case 13 and three cut-and-raised portions 17 are provided substantially corresponding to the cut-and-raised portions 16. FIG. 4 (b) is a diagram showing the D in FIG. 4 (a).
It is an expanded sectional view of the -D part. Since the cut-and-raised portion 16 is generally processed with a thin iron-based metal plate, it can be easily made elastic. h4 is the height of the cut and raised portion 17. Further, there is a relationship of h3 + h4> h1 + h2, and preferably, h3 = h4, h1 = h2, and
The relationship of h3> h1 or h4> h2 is good. As a result, free vibration of the two-layer stator portion in the housing 1 can be eliminated.

FIG. 5 is a perspective view for explaining a second embodiment of the present invention. FIG. 5 shows an example in which a cut-and-raised portion of the cup-shaped case 13 or the bracket 14 has a hemispherical convex portion 18 formed at the tip. Naturally, in the case of the cut-and-raised portion of the bracket 14, the convex portion 18 faces downward.

FIG. 6 is a sectional view for explaining a third embodiment of the present invention. In the third embodiment, the outer stator core 8 (8
a or 8b), a through hole 19 is provided in a portion thereof. Third
In the embodiment of FIG.
Reference numerals 17 and 18 press the outer stator core 8 side. Therefore, the stators of the first and second layers can be free from free vibration due to radial and axial gaps with respect to the rotor shaft, and can be reliably positioned. In the case of the bracket 14, the projection 1
6, or 18 is facing down.

FIG. 7 is a sectional view for explaining a fourth embodiment of the present invention. A portion of the outer stator core 8 (8a or 8b) that contacts the cut-and-raised portions 16, 17, and 18 is provided with a spherical concave portion 20 slightly smaller than the diameter of the spherical convex portion of the cut and raised portions 16, 17, and 18; Also make a recess in the corresponding part. In this way, the same effects as in FIG. 6 can be obtained by fitting them together in the assembly and lamination.

In the above embodiment, an example of a fixed shaft type motor has been described. However, a rotor is fixed to a shaft, and this shaft is rotatably supported by bearings.
It goes without saying that a gear may be provided on the output side of the shaft to be of a shaft rotation type. Also, the case has been described as a cup-shaped case and the bracket is a flat plate, but it is obvious that the case may be a flat plate and the bracket may be an inverted cup type.

[0016]

According to the present invention, there is provided a magnet rotary type motor in which a plurality of stators are stacked in a housing comprising a cup-shaped case and a bracket as described above. The stacked stator portions are sandwiched by the elastic cut-and-raised portions, so that the stacked stator portions can be reliably pressed and clamped, so that the processing of each part can be easily managed and the motor can be started at the time of starting the motor. In addition, it is possible to prevent the stator from vibrating during rotation, thereby preventing noise.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a main part showing a first embodiment of the present invention.

FIG. 2 is an enlarged sectional view of a part of FIG.

FIG. 3 is a plan view showing the bracket 14 of FIG.

FIG. 4 is a plan view for explaining the cup type case 13 of FIG. 1;

FIG. 5 is a perspective view showing a second embodiment of the present invention.

FIG. 6 is a cross-sectional view for explaining a third embodiment of the present invention.

FIG. 7 is a sectional view for explaining a fourth embodiment of the present invention.

FIG. 8 is a sectional view of a conventional claw-pole type stepping motor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Housing 2,13 Cup type case 3,14 Bracket 4 Fixed shaft 5 Rotor 6 Bearing part g, 15 Gear 7 Ring magnet 8 Outer stator core 9 Inner stator core 10 Coil bobbin 11 Coil 12 Stator 13 Cup type case 14 Bracket 16 First cut Raised part 17 Second cut-raised part 18 Convex part 19 Through-hole 20 Recess 21 Recess

Claims (5)

[Claims] 1. A rotating magnet motor comprising a plurality of stators stacked in a housing consisting of a case and a bracket, wherein the housing is provided with a plurality of elastically cut and raised portions in the stator stacking direction. A housing structure of a magnet rotary motor in which the laminated stator is sandwiched by elastically cut and raised portions. 2. The cut-and-raised portion is provided at a position substantially corresponding to a case and a bracket.
The housing structure of the magnet rotary motor according to the above. 3. The cut-and-raised portion has a wave-like or hemispherical tip at the tip.
The housing structure of the magnet rotary motor according to the above. 4. The stator according to claim 1, wherein the portion of the stator sandwiched between the cut-and-raised portions is a through hole.
A housing structure for the magnet rotary motor according to claim 3. 5. The stator according to claim 1, wherein a portion of the stator held by the cut-and-raised portion is a concave portion.
A housing structure for the magnet rotary motor according to claim 3.