JP4498050B2 - Inner rotor type brushless motor - Google Patents

Description

  The present invention relates to an inner rotor type brushless motor having a plurality of amateur cores and a magnetic circuit constituting member to which an outer peripheral portion of the amateur core is press-fitted and fixed.

  There exists patent document 1 as a prior art example of an inner rotor type brushless motor. Most of the windings of this type of inner rotor brushless motor are applied from the inner circumference to the teeth that protrude toward the inside of the stacked armature cores. For the purpose of improving the utilization factor or the like, a method is used in which winding is performed by dividing the shape into teeth that can be wound from the outer peripheral side or for each tooth portion, and then coupled to a magnetic circuit component member. This conventional example is shown in FIGS.

  FIG. 5 is a plan view showing one of a plurality of armature cores of a conventional inner rotor type brushless motor which is divided into teeth for each of the teeth portions and provided with a winding. In this conventional example, a winding is wound around the tooth portion 101 a of each amateur core 101, and then the outer peripheral portion 101 b of each amateur core 101 is fixed to the inner peripheral portion of the magnetic circuit constituent member 102. Yes.

FIG. 6 is a cross-sectional view showing the configuration of another conventional inner rotor brushless motor that is similarly divided into teeth and wound. In this brushless motor, a magnet 203 is fixed via an attachment member 202 fixed to a rotating shaft 201, and constitutes a rotating portion. The plurality of armature cores 204 are provided with resin members 205 that serve as both insulation and positioning. A plurality of teeth 204a projecting inward are multi-poles whose energization is sequentially switched by the pole position of the magnet 203. A winding 206 for generating a magnetic field is wound from the outside, and a rotational force is obtained between the magnets 203 magnetized to opposite multipoles. The armature core 204 around which the winding 206 is wound is coupled to the inner peripheral surface of the magnetic circuit constituting member 208 via a low magnetic resistance member 207.
JP 2002-345223 A

  However, in the conventional example of FIG. 5, there is a possibility that a magnetic resistance is generated at a joint portion between the armature core 101 and the magnetic circuit constituent member 102 and the motor characteristics are deteriorated. For this reason, it is effective to suppress the magnetic resistance so as not to cause clearance by press-fitting the coupling portion, but in order to prevent the occurrence of scraping due to plastic deformation while maintaining a predetermined strength, the coupling portion is It was necessary to apply with high precision. That is, it is necessary to finish the outer peripheral portion 101b of the armature core 101 and the inner peripheral portion of the magnetic circuit constituent member 102 with high accuracy.

  Further, in the conventional example of FIG. 6, it is necessary to interpose a low magnetic resistance separate member (low magnetic resistance member 207) in the coupling portion to prevent deterioration of the characteristics. Had a problem.

(Object of invention)
The object of the present invention is to suppress the clearance between the outer peripheral portion of the armature core and the magnetic circuit constituent member without requiring high-precision machining or additional members, and prevent deterioration of motor characteristics due to increase in magnetic resistance. An inner rotor type brushless motor is to be provided.

To achieve the above object, an inner rotor type brushless motor of the present invention includes a rotating member comprising a magnet, and a plurality of armature cores are positioned by the resin member which also serves as an electrical insulation around said rotary body, said In an inner rotor type brushless motor having a magnetic field generating winding wound around a plurality of armature cores and a cylindrical magnetic circuit constituting member on which outer peripheral portions of the plurality of armature cores are press-fitted and fixed . A plurality of amateur cores are laminated and formed by being joined and fixed at a joint part, and a projecting part is provided on both sides of the outer peripheral part of the armature core, and a peripheral part including the projecting part is elastic. with deformable portions are provided, wherein the elastically deformable portion not be provided the coupling portion, front outer periphery of the armature core When press-fitted into a member for the magnetic circuit structure, wherein the elastically deformable portion is elastically deformed inwardly, by press-fitted into the inner peripheral surface of the magnetic circuit structure member, the projection of the outer periphery of the armature core parts is characterized in that so as to intimate contact with the inner peripheral surface of at least the magnetic circuit configuration member.

  In the above configuration, the projecting portions are provided at symmetrical positions on both sides of the outer peripheral portion of the armature core, and the outer periphery including the projecting portions is elastically deformed so that the periphery of the protruding portion is elastically deformed, thereby forming the magnetic circuit constituent member. By press-fitting and fixing, a predetermined strength is obtained by the stress of the press-fitting, and a clearance generated between the outer peripheral portion of the armature core and the inner peripheral surface of the magnetic circuit constituting member is suppressed to reduce the magnetic resistance.

  According to the present invention, it is possible to suppress the clearance between the outer peripheral portion of the armature core and the magnetic circuit constituent member without requiring high-precision machining and additional members, and to prevent deterioration of motor characteristics due to increase in magnetic resistance. An inner rotor type brushless motor can be provided.

  As shown in the following examples.

  1 to 4 are diagrams according to an embodiment of the present invention. Specifically, FIG. 1 is a cross-sectional view of an inner rotor type brushless motor, and FIG. 2 is a plan view of the armature core of FIG. FIG. 3 is a plan view showing a modification of the armature core of FIG. 2, and FIG. 4 is a plan view showing the armature core of FIG.

  As shown in FIG. 1, a magnet 3 is fixed via an attachment member 2 fixed to a rotating shaft 1 to constitute a rotating portion. A plurality of teeth 4a projecting toward the inside of a substantially H-shaped armature core 4 formed by laminating a plurality of sheets are provided with a multipolar magnetic field generating winding 6 that can be sequentially switched in accordance with the pole position of the magnet 3. A rotational force is obtained between the magnets 3 which are wound and magnetized to the opposite multipoles. A resin member 5 is provided for the purpose of electrical insulation and positioning with respect to a portion around which the winding 6 is wound.

  As shown in FIG. 2A, a projecting portion 4 b having a t <b> 1 dimension is provided at both sides symmetrical positions of the outer peripheral portion of the armature core 4. Moreover, the thin part 4c is provided in the peripheral part containing this protrusion part 4b so that elastic deformation is possible. The thin-walled portion 4c is not necessary when the amount of interference fit near the protruding portion 4b is small.

Here, an example of the manufacturing process from the manufacture of the armature core 4 to the press-fitting of the armature core 4 into the cylindrical magnetic circuit constituting member 7 will be enumerated below.
(1) Press punching of single amateur core (2) Lamination of amateur core (by caulking / adhesion / welding etc.)
(3) Assembling a plurality of laminated amateur cores 4 to the resin member 5 (light press-fitting etc.)
(4) Winding the winding 6 around the amateur core 4 from the outer periphery (for multiple amateur cores)
(5) Press-fit the member assembled in (4) above into the cylindrical magnetic circuit constituent member 7 (5) will be described in more detail. The outer peripheral portion including the protruding portion 4b of the armature core 4 is configured as a magnetic circuit. When coupled to the member 7, the vicinity of the protrusion 4 b is elastically deformed in the inner direction along the inner peripheral surface of the cylindrical magnetic circuit constituent member 7. Then, as shown in FIG. 4, the protruding portion 4b is in close contact with the inner peripheral surface of the magnetic circuit constituting member 7, and the outer peripheral portion between the protruding portions 4b has a slight clearance t2 inside the magnetic circuit constituting member 7. It is almost in close contact with the peripheral surface. Therefore, the projecting dimension of the projecting part 4b is reduced by the dimension of (t1-t2), and the outer peripheral part including the projecting part 4b of the armature core 4 is press-fitted and fixed to the inner peripheral surface of the magnetic circuit constituent member 7. Thus, the magnetic resistance between them can be reduced to a level that does not cause deterioration of characteristics without making the coupling portion highly accurate as in the conventional case of FIG.

  The protrusion 4b has two functions of being in close contact with the magnetic circuit constituent member 7 even if it is partial, allowing a large amount of magnetic flux to pass therethrough, and mechanically fixing. Moreover, the effect of reducing the t2 dimension (gap distance) is expected by elastically deforming the vicinity of the protrusion 4b inward.

  Note that the t2 dimension can be set to be substantially 0 within a range in which the magnetic resistance is not increased. Moreover, the shape of the thin part 4c is not limited to FIG. 2, and it is not necessarily required if this part can be elastically deformed. Further, as shown in FIG. 2B, a plurality of laminated armature cores 4 are respectively connected and fixed by welding, adhesion, caulking, etc., but maintain close contact with the magnetic circuit constituent member 7 side. Depending on the purpose, the connecting portion is not provided in a portion (the thin plate portion 4c portion) that can be elastically deformed.

  3 shows an example in which the shape of the protruding portion 4b of the amateur core 4 shown in FIG. 2 is changed, and a protruding portion 4b ′ having a t1 dimension is formed on the outer periphery of the amateur core 4 ′. Also, a thin portion 4c ′ is provided so that the peripheral portion can be elastic. Here, one protrusion 4b 'is provided at each end, but two may be provided.

  According to the above embodiment, the protrusions 4a and 4a 'are provided for coupling on a part of the outer peripheral part of the armature cores 4 and 4', and the vicinity of the protrusions 4a and 4a 'is formed into a shape that can be elastically deformed. Therefore, the increase in magnetic resistance due to the clearance between the outer peripheral portion of the armature cores 4 and 4 ′ and the magnetic circuit component member 7 can be prevented without requiring high-precision processing and additional members as in the prior art. An inner rotor brushless motor that does not deteriorate the characteristics can be obtained.

It is sectional drawing which shows the inner rotor type brushless motor concerning the Example of this invention. It is a top view which shows the amateur core of FIG. It is a top view which shows the modification of the amateur core of FIG. It is a top view which shows the armature core of FIG. 1, and its outer peripheral part periphery. It is a top view which shows one of the amateur cores with which the conventional inner rotor type brushless motor is comprised. It is sectional drawing which shows the structure of the other conventional inner rotor type brushless motor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rotating shaft 2 Mounting member 3 Magnet 4, 4 'Amateur core 4a, 4a' Teeth part 4b, 4b 'Protrusion part 4c, 4c' Thin part 5 Resin member 6 Winding 7 Magnetic circuit constituent member

Claims (1)

A rotary body including a magnet, and a plurality of armature cores are positioned by the resin member which also serves as an electrical insulation around the rotating body, and the magnetic field generating windings wound on said plurality of armature core, said plurality An inner rotor type brushless motor having a cylindrical magnetic circuit constituent member on which an outer peripheral portion of the armature core is press-fitted and fixed ,
Around the plurality of armature cores are plurally stacked, there is formed by being fixedly coupled at the junction, the projecting portions are provided on both sides symmetrical positions of the outer periphery of the armature core, including the projecting portions The part is provided with an elastically deformable part, and the joint part is not provided in the elastically deformable part,
When the outer peripheral portion of the armature core is press-fitted and fixed to the magnetic circuit component member , the elastically deformable portion is elastically deformed inward, and press-fitted and fixed to the inner peripheral surface of the magnetic circuit component member, An inner rotor type brushless motor characterized in that the projecting portion of the outer peripheral portion of the amateur core is in close contact with at least the inner peripheral surface of the magnetic circuit constituting member.

Images