JP2008148451A - Electric motor and method of assembling same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric motor capable of improving sealing performance of a portion where a harness is led out to the outside and improving dustproof/waterproof effects, and to provide a method of assembling the electric motor. <P>SOLUTION: The electric motor 1 includes a yoke housing 2 having an opening 9; a rotary shaft 5 rotatably supported by the yoke housing 2; a resolver 25 for detecting a rotation angle of the rotary shaft 5; and a bracket 30 attached on the opening 9 of the yoke housing 2, wherein an insertion hole 34 for inserting a harness 35 of the resolver 25 is formed on the bracket 30 and a grommet 36 for dustproof/waterproof is provided on the insertion hole 34. A resolver holder 40 for restricting the movement of the resolver stator 25b in an axial line direction and a rotation direction is provided on the resolver 25, an extending portion 52 for supporting the grommet 36 from the inside and a pressing plate 53 are provided on the resolver holder 40, and a plate 38 for pressing the grommet 36 from the outside is provided on the bracket 30. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electric motor mounted on a vehicle such as an automobile and an assembling method of the electric motor.

2. Description of the Related Art Conventionally, for example, a DC motor including a resolver that detects a rotation angle of a rotation shaft is known as an electric motor mounted on a vehicle such as an automobile.
This type of electric motor has a stator press-fitted into a bottomed cylindrical yoke housing, and a rotor provided to be rotatable with respect to the stator.
The stator has a substantially cylindrical stator core, and a winding is wound after an insulating member is mounted on the stator core. In the rotor, a permanent magnet and a resolver rotor of a position detecting resolver are arranged in order on a rotating shaft. The permanent magnet is magnetized so that the magnetic poles change in order in the circumferential direction.

  A bracket for attaching the electric motor to the vehicle is provided in the opening of the yoke housing, and a resolver stator that constitutes a resolver together with the resolver rotor is attached to a portion corresponding to the resolver rotor of the bracket. The resolver stator is restricted from moving in the axial direction relative to the rotation axis and in the rotation direction by a resolver holder fastened and fixed to the bracket. The harness connected to the resolver is pulled out of the electric motor through a grommet for dustproof and waterproof.

The grommet is fixed so as to be sandwiched between the yoke housing and the bracket. By configuring in this way, the sealability between the yoke housing and the grommet and the bracket and the grommet at the portion where the harness is pulled out is secured (for example, see Patent Document 1).
JP 2004-323019 A

  However, the grommet is opened in a direction intersecting the direction in which the yoke housing and the bracket are compressed only by sandwiching the grommet provided in the harness pull-out portion between the yoke housing and the bracket as in the above-described conventional technology. Therefore, there is a problem that it is difficult to ensure complete sealing performance.

  Accordingly, the present invention has been made in view of the above-described circumstances, and provides an electric motor and an electric motor assembling method capable of improving the sealing performance of a portion where a harness is pulled out and improving the dustproof and waterproof effect. It is to provide.

In order to solve the above problems, the invention described in claim 1 is a yoke housing having an opening, a rotating shaft rotatably supported by the yoke housing, and a resolver for detecting a rotation angle of the rotating shaft. And a bracket attached to the opening of the yoke housing, the insertion hole for inserting a lead wire for connecting to the harness of the resolver or an external power source is formed in the bracket, and the dustproof and waterproofing is formed in the insertion hole The resolver comprises: a resolver rotor that rotates integrally with the rotary shaft; and a resolver stator that is disposed outside the resolver rotor, and the resolver stator includes the resolver stator. A resolver holder is provided for restricting movement in the axial direction and the rotational direction of the rotating shaft. Provided with a supporting member for supporting the Met from the inside, characterized in that a plate for pressing the grommet into the bracket from the outside.
In this case, as in the invention described in claim 2, the bracket and the plate may be integrally formed.
By comprising in this way, a grommet can be compressed along the axial direction of an insertion hole, and also a compressive force can be made to act also in the direction which cross | intersects an axial direction.

The invention described in claim 3 is the method for assembling the electric motor according to claim 1 or 2, wherein the harness is inserted into the grommet in advance, and the harness is externally connected to the end opposite to the resolver side. After the coupler for connecting to the connection terminal is attached, the resolver is assembled to the bracket.
By setting it as such an assembly method, it becomes possible to unitize a resolver, a harness, a grommet, and a coupler previously.

According to the present invention, the grommet can be compressed along the axial direction of the insertion hole, and a compressive force can also be applied in a direction intersecting the axial direction. As a result, the grommet spreads outward in the direction intersecting the compression direction, and the sealing function can be exerted on the entire periphery of the grommet to improve the adhesion between the grommet and the insertion hole. For this reason, the sealing property of a harness drawer part can be made reliable, and the electric motor excellent in dustproof waterproofness can be provided.
In addition, since the resolver, harness, grommet, and coupler can be unitized in advance, the assembly work efficiency of the electric motor can be improved.

Next, embodiments of the present invention will be described with reference to the drawings.
As shown in FIGS. 1 and 2, the electric motor 1 is a motor with a DC brush, and has a configuration in which an armature 3 is rotatably disposed in a bottomed cylindrical yoke housing 2. A permanent magnet 4 is fixed to the inner peripheral surface of the yoke housing 2. The permanent magnet 4 is magnetized so that the magnetic poles change in order in the circumferential direction.

  An outer flange 2 a is formed at the opening edge of the yoke housing 2. On the other hand, the end portion (bottom portion) 2b of the yoke housing 2 is formed with a recess 26 in the center in the radial direction, and a bearing 27 is press-fitted into the recess 26. One end of the rotating shaft 5 of the armature 3 is rotatably supported by the bearing 27.

The armature 3 has an armature core 6 and a commutator (commutator) 13 arranged in order on a rotating shaft 5, and a resolver that detects the rotation angle of the rotating shaft 5 is disposed at the other end of the rotating shaft 5. Twenty-five resolver rotors 25a are provided.
The armature core 6 is obtained by laminating a plurality of ring-shaped metal plates 8 in the axial direction. A plurality of T-shaped teeth (not shown) are radially formed on the outer peripheral portion of the metal plate 8 at equal intervals along the circumferential direction.

  By fitting a plurality of metal plates 8 to the rotation shaft 5, dovetail-shaped slots (not shown) are formed between adjacent teeth on the outer periphery of the armature core 6. The slots extend along the axial direction, and a plurality of slots are formed at equal intervals along the circumferential direction. An enamel-wrapped winding 12 is wound between the slots, whereby a plurality of armature coils 7 are formed on the outer periphery of the armature core 6.

  The commutator 13 is for performing so-called rectification that switches the direction of the current flowing through the armature coil 7. A plurality of segments 14 made of a conductive material are attached to the outer peripheral surface of the commutator 13. The segment 14 is made of a plate-like metal piece that is long in the axial direction, and is fixed in parallel at equal intervals along the circumferential direction while being insulated from each other.

  A riser 15 is integrally formed at an end portion of each segment 14 on the armature core 6 side and is bent in a manner of being folded back to the outer diameter side. A winding 12 serving as a winding start end and a winding end end of the armature coil 7 is wound around the riser 15, and the winding 12 is fixed to the riser 15 by fusing. Thereby, the segment 14 and the armature coil 7 corresponding to this are electrically connected.

  A substantially disc-shaped cover 17 is provided in the opening 9 of the yoke housing 2. The cover 17 is integrally formed with a coupler 28 for connecting an external connector. A cylindrical fitting portion 18 is provided at the radial center of the cover 17. The yoke housing 2 side of the fitting portion 18 is fitted to the peripheral wall 2 c of the yoke housing 2. As a result, the cover 17 is fixed to the yoke housing 2.

  A brush (not shown) is attached to the inside of the cover 17 via a spring (not shown). The brush is electrically connected to the terminal 28a of the coupler. Further, since the brush is urged toward the commutator 13 by a spring, it is in sliding contact with the segment 14. As a result, external power is supplied to the commutator 13 via the brush.

  A bracket 30 is provided on the opposite side of the cover 17 from the yoke housing 2 so as to cover the cover 17. The bracket 30 is for attaching the electric motor 1 to the vehicle, and is formed in a bottomed cylindrical shape. The bottom wall 30a is provided with two bolt holes 22 (see FIG. 2). The bracket 30 has a bolt (not shown) screwed into the bolt hole 22 and is fastened and fixed to an outer flange 2 a formed at the opening edge of the yoke housing 2. A recess 31 corresponding to the outer shape of the cover 17 is formed in the bottom wall 30 a of the bracket 30.

A hole 20 is formed in the recess 31 at the center in the radial direction. A bearing 21 is press-fitted and fixed in the hole 20, and the rotating shaft 5 is rotatably supported by the bearing 21.
Further, a recess 32 is formed in the bottom wall 30a of the yoke housing 2 on the surface opposite to the recess 31, and a resolver stator 25b that constitutes the resolver 25 together with the resolver rotor 25a is fitted and fixed thereto.

  The resolver stator 25b is fixed corresponding to the mounting position of the resolver rotor 25a, and can detect the rotation angle of the resolver rotor 25a that rotates integrally with the rotary shaft 5. A harness 35 is connected to the resolver stator 25b via a terminal box 43, and a coupler 19 for connecting to an external connector (not shown) is connected to the opposite end of the harness 35 to the terminal box 43. Yes.

  As shown in FIG. 1, a boss portion 33 is formed on the peripheral wall 30b of the bracket 30, and an insertion hole 34 penetrating the peripheral wall 30b is formed therein. The insertion hole 34 is for drawing out the harness 35 and the coupler 19 connected to the resolver stator 25b to the outside, and the cross-sectional shape of the insertion hole 34 is formed so that the coupler 19 can be inserted. A grommet 36 that is aligned with the inner surface of the insertion hole 34 is fitted into the insertion hole 34 in order to prevent the entry of dust and water from the outside. The grommet 36 has an outer shape corresponding to the insertion hole 34 of the boss portion 33, and a hole 37 through which the harness 35 can be inserted is formed at a substantially central portion.

  Here, the grommet 36 is compressed so as to be sandwiched from the axial direction of the insertion hole 34 by the plate 38 that closes the insertion hole 34 of the boss portion 33 from the outside and the resolver holder 40 attached to the resolver stator 25b. ing. The plate 38 is formed so as to correspond to the outer shape of the boss portion 33, and is fastened and fixed to the boss portion 33 by bolts 41 (see FIG. 2). A hole 39 through which the coupler 19 can be inserted and which is smaller than the cross-sectional shape of the insertion hole 34 is formed in the approximate center of the plate 38.

The resolver holder 40 is for restricting movement of the resolver stator 25b in the axial direction with respect to the rotation shaft 5 and in the rotation direction, and is fastened and fixed to the peripheral wall 32a forming the recess 32 of the bracket 30 by bolts 42. Has been.
As shown in FIGS. 1, 3A, and 3B, the resolver holder 40 is formed by pressing a metal plate material and has a substantially annular holder body 45. ing. The holder main body 45 includes a concave portion 46 formed substantially in the center in the radial direction, and a flange portion 51 that continues to the opening edge of the concave portion 46.

  The concave portion 46 is for externally fixing and fixing the resolver stator 25b, and includes a peripheral wall 46a and an upper wall 46b. The resolver stator 25b is fitted to the peripheral wall 46a. A hole 47 that substantially matches the outer diameter of the resolver rotor 25a is formed in the upper wall 46b of the recess 46 at a substantially center in the radial direction, and the rotary shaft 5 of the armature 3 passes through the hole 47 (FIG. 1). reference).

  The depth H1 of the recess 46 is set to be larger than the height H2 (see FIG. 1) from the flange portion 24 formed at the center in the axial direction of the resolver stator 25b to the upper surface 44 of the resolver stator 25b. Thus, when the holder main body 45 is fitted and fixed to the resolver stator 25b, a gap is formed between the upper wall 46b of the recess 32 and the upper surface 44 of the resolver stator 25b.

  That is, the movement of the resolver stator 25b in the axial direction is restricted by the flange portion 51 of the holder body 45 overlapping the flange portion 24 of the resolver stator 25b fitted and fixed to the recess 32. In the flange portion 24 of the resolver stator 25b, a plurality of grooves 23 formed along the axial direction are formed at equal intervals in the circumferential direction.

  The holder main body 45 is formed with two protrusions 49 at portions corresponding to the bolts 42 screwed into the recesses 32, and bolt holes 48 are formed therein. Further, the holder main body 45 is formed with a notch 50 corresponding to the terminal box 43 of the resolver stator 25b. A tongue piece 54 is provided in the recess 46 of the holder main body 45 on the side opposite to the notch 50.

The tongue piece 54 extends from the peripheral wall 46a of the recess 46 toward the resolver stator 25b (on the side opposite to the recess 46, the lower side in FIG. 1). Further, the tongue piece 54 is formed so as to correspond to the groove 23 of the flange portion 24 in the resolver stator 25b.
That is, the movement of the resolver stator 25b in the rotational direction is restricted by the tongue piece portion 54 formed in the holder main body 45 being interposed in the groove 23 of the flange portion 24 in the resolver stator 25b. Further, the notch 50 corresponding to the terminal box 43 is formed in the holder main body 45, thereby restricting the horizontal movement of the terminal box 43 and protecting the terminal box 43.

The flange portion 51 of the holder main body 45 includes an extension portion 52 that extends from the side opposite to the notch portion 50 toward the boss portion 33 of the bracket 30 (to the right side in FIG. 3), and this extension portion. A pressing plate 53 that is bent from the tip of 52 to the armature 3 side and extends along the axial direction is provided in series.
The length L1 of the extending portion 52 is set to a length that allows the pressing plate 53 to press the inner surface 36a of the grommet 36. The presser plate 53 has a notch 55 for preventing interference between the harness 35 and the presser plate 53.

Next, a method for assembling the electric motor 1 will be described.
First, the permanent magnet 4 is attached to the inner peripheral surface of the yoke housing 2, and the bearing 27 is press-fitted and fixed in the recess 26 formed in the end portion 2 b of the yoke housing 2.
Next, the armature 3 is assembled. First, the armature core 6 is attached to the rotating shaft 5, and the armature coil 7 is wound around the armature core 6.

Then, the commutator 13 is attached to the rotary shaft 5, and then the winding 12 of the armature coil 7 is wound around the riser 15 integrally formed with the segment 14 of the commutator 13, and the winding 12 is fixed to the riser 15 by fusing. Note that the armature coil 7 may be wound around the armature core 6 after the commutator 13 is attached to the rotating shaft 5.
Then, the armature 3 assembled in this way is set in the yoke housing 2.

  After setting the armature 3 in the yoke housing 2, the cover 17 with the brush attached is set in the opening 9 of the yoke housing 2, and the bracket 30 with the bearing 21 attached in the hole 20. Then, the resolver rotor 25 a is attached to the other end side of the rotating shaft 5, while the resolver stator 25 b is attached to the recess 32 of the bracket 30.

  Here, as shown in FIG. 4, the resolver stator 25b is connected to the harness 35 in advance, and the harness 35 is inserted into the grommet 36 and the coupler 19 is connected to the end of the harness 35 opposite to the resolver stator 25b. deep. After the resolver stator 25b of the resolver unit 60 thus unitized is attached to the recess 32 of the bracket 30, the harness 35 and the coupler 19 are moved from the inside of the bracket 30 to the outside through the insertion hole 34 of the boss portion 33. And pull out.

  After the harness 35 and the coupler 19 are pulled out, the grommet 36 of the resolver unit 60 is inserted into the insertion hole 34. Then, the plate 38 is fastened and fixed to the boss portion 33 with bolts 41, the resolver holder 40 is set to the resolver stator 25 b, and the resolver holder 40 is fastened and fixed to the peripheral wall 32 a of the recess 32 with bolts 42. This completes the assembly of the electric motor 1.

  Therefore, according to the above-described embodiment, the extending portion 52 and the pressing plate 53 are provided in the resolver holder 40 for restricting movement of the resolver stator 25b in the axial direction with respect to the rotation shaft 5 and in the rotation direction. The grommet 36 inserted into the insertion hole 34 of the boss portion 33 can be supported from the inside. Further, since the plate 38 is attached to the boss portion 33 of the bracket 30, the grommet 36 can be pressed from the outside. For this reason, the grommet 36 can be set at a desired position.

  Moreover, since the length L1 of the extending portion 52 of the resolver holder 40 is set to a length that allows the pressing plate 53 to press the inner surface 36a of the grommet 36, the grommet 36 is pressed against the pressing plate 53 and the plate 38. And can be compressed along the axial direction of the insertion hole 34. As a result, the grommet 36 expands outward in the direction intersecting the compression direction, and the sealing function can be exerted around the grommet 36 to improve the adhesion between the grommet 36 and the insertion hole 34. . For this reason, the sealing performance by the grommet 36 is improved, and it becomes possible to provide the electric motor 1 having excellent dustproof and waterproof properties.

It is also conceivable to apply a sealing agent or the like between the grommet 36 and the insertion hole 34 in order to improve the sealing performance of the grommet 36. However, according to this embodiment, since the sealing performance of the grommet 36 can be improved only by providing the extending portion 52 and the pressing plate 53 in the conventional resolver holder, the amount of the sealing agent is reduced, or the sealing agent Can be abolished. For this reason, the manufacturing cost can be reduced.
Furthermore, according to the above-described embodiment, the resolver 25 (resolver stator 25b), the harness 35, and the coupler 19 can be unitized in advance as the resolver unit 60, so that the assembly work efficiency of the electric motor 1 is improved. Can be made.

The present invention is not limited to the above-described embodiment, and includes various modifications made to the above-described embodiment without departing from the spirit of the present invention.
Moreover, although the above-mentioned embodiment demonstrated the case where the electric motor 1 was a motor with a DC brush, it is not restricted to this, A DC brushless motor may be sufficient.
Further, in the above-described embodiment, the case where the boss portion 33 of the bracket 30 is provided with the plate 38 for pressing the grommet 36 from the outside is not limited to this, and the plate 38 may be integrally formed with the bracket 30. Good. In this case, since the number of parts of the electric motor 1 can be reduced, the manufacturing cost can be further reduced.

And in the above-mentioned embodiment, although the penetration hole 34 was formed in the boss | hub part 33 of the bracket 30, and the harness 35 of the resolver stator 25b was pulled out here via the grommet 36, it was not restricted to this. For example, a lead wire or the like for connecting to an external power source may be inserted through the grommet 36.
Moreover, although the above-mentioned embodiment demonstrated the case where the grommet 36 was supported from the inner side by the extension part 52 and the pressing plate 53 which were provided in the resolver holder 40, this is applied and other components are applied to the resolver holder 40. You may add the supporting member to support.

It is a longitudinal cross-sectional view of the electric motor in embodiment of this invention. It is a top view of the electric motor in the embodiment of the present invention. The resolver holder in embodiment of this invention is shown, (a) is a top view, (b) is sectional drawing which follows the AA line of (a). It is a block diagram of the resolver unit in embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electric motor 2 Yoke housing 5 Rotating shaft 9 Opening part 19 Coupler 25 Resolver 25a Resolver rotor 25b Resolver stator 30 Bracket 34 Insertion hole 35 Harness 36 Grommet 38 Plate 40 Resolver holder 52 Extension part (support member)
53 Presser plate (supporting member)
60 resolver unit

Claims (3)

A yoke housing having an opening; a rotating shaft rotatably supported by the yoke housing; a resolver for detecting a rotation angle of the rotating shaft; and a bracket attached to the opening of the yoke housing.
An electric motor in which an insertion hole for inserting a lead wire for connecting to the harness of the resolver or an external power source is formed in the bracket, and a grommet for dustproof and waterproof is provided in the insertion hole,
The resolver includes a resolver rotor that rotates integrally with the rotating shaft, and a resolver stator that is disposed outside the resolver rotor,
The resolver is provided with a resolver holder that restricts movement of the resolver stator in the axial direction and the rotational direction,
An electric motor comprising: a support member that supports the grommet from the inside on the resolver holder; and a plate that presses the grommet from the outside on the bracket.   The electric motor according to claim 1, wherein the bracket and the plate are integrally formed. An electric motor assembling method according to claim 1 or 2,
The electric motor is characterized in that the harness is inserted into the grommet in advance, a coupler for connecting to an external connection terminal is attached to an end opposite to the resolver side of the harness, and then the resolver is assembled to the bracket. Assembling method of motor.

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