JP2008148450A - Electric motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric motor capable of improving earthquake resistance by suppressing wobbling of an axial direction of a terminal unit and preventing disconnection of a connection portion between the terminal unit and a coil. <P>SOLUTION: The electric motor 1 includes a housing 2 having an opening 27; a stator 3 fixed in the housing 2 and having a coil 12 wound thereon; a rotor 4 rotatably supported in the inside of the stator 3; a bracket 7 attached on the opening 27 of the housing 2; and a terminal unit 30 electrically connected to the coil 12. The electric motor 1 includes a regulating member 40 for pressing and holding the terminal unit 30 onto the stator 3 side via the bracket 7. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electric motor used for a vehicle brake device, for example.

2. Description of the Related Art Conventionally, a vehicle brake device that generates a braking force by an output torque of an electric motor is known.
Many of the electric motors used in this brake device are of the brushless type including a stator fixed in a bottomed cylindrical housing and a rotor rotatably provided inside the stator. The stator has a substantially annular stator core, and a coil is wound after an insulator, which is an insulating material, is attached to the stator core. In the rotor, a magnet and a resolver rotor of a position detection resolver are sequentially arranged on a rotation shaft.

  A bracket is attached to the open end of the housing, and a terminal unit is provided on the stator side of the bracket. The terminal unit has a role of electrically connecting the coil wound around the stator and the lead wire drawn from the outside of the electric motor, and from the external power source connected via the lead wire to the coil. Current supply is possible.

By the way, this type of electric motor is required to have a vibration proof performance because of its location. Therefore, the terminal unit is provided with a claw portion, and the insulator is provided with an engagement hole that engages with the claw portion, and the terminal unit is fixed to the insulator so as to improve the vibration resistance of the joint portion between the terminal unit and the coil. A technique has been proposed (see, for example, Patent Document 1).
JP 2002-78272 A

  However, in the above-described prior art, since the claw portion and the insulator of the terminal unit are each formed of resin, rattling due to vibration is likely to occur. In addition, since it is difficult to manage the dimensions of the claw portion and the engagement hole, the clearance between the two is inevitably increased, and there is a possibility that the backlash in the axial direction of the terminal unit is further increased. For this reason, there is a problem that a large stress is applied to the joint portion between the terminal unit and the coil, and the joint portion may be disconnected.

  Therefore, the present invention has been made in view of the above-described circumstances, and suppresses backlash in the axial direction of the terminal unit and prevents breakage of the joint portion between the terminal unit and the coil, thereby improving the earthquake resistance. An electric motor that can be used is provided.

In order to solve the above-mentioned problem, the invention described in claim 1 is a housing having an opening, a stator fixed in the housing and wound with a coil, and rotatable inside the stator. An electric motor comprising: a rotor supported by the housing; a bracket attached to the opening of the housing; and a terminal unit electrically connected to the coil. The terminal unit is connected to the stator side via the bracket. It is characterized in that a regulating member for pressing and holding is provided.
By configuring in this way, the terminal unit can be restricted from moving in the axial direction by the restricting member without providing a claw in the terminal unit or providing an engagement hole in the insulator of the stator. And the stator can be integrated.

According to a second aspect of the present invention, the restricting member has a cylindrical portion surrounding the terminal unit, and an inner flange portion that presses the terminal unit toward the stator is provided on one end side of the cylindrical portion. An outer flange portion formed between the housing and the bracket is formed on the other end side of the cylindrical portion.
By comprising in this way, since a cylindrical part surrounds the circumference | surroundings of a terminal unit, a contact with a terminal unit and a bracket can be prevented.
Further, the inner flange portion can function as a pressing plate that presses the terminal unit toward the stator.
Further, since the outer flange portion is sandwiched between the housing and the bracket, the regulating member is securely fixed in the electric motor without rattling.

According to the first aspect of the present invention, the movement of the terminal unit in the axial direction can be regulated by the regulating member without providing the claw portion in the terminal unit or providing the engaging hole in the insulator of the stator. The terminal unit and the stator can be integrated. For this reason, while reducing the manufacturing cost of terminal units and insulators,
It is possible to prevent disconnection of the joint portion between the terminal unit and the coil, and to provide an electric motor with excellent vibration resistance.

According to the invention described in claim 2, since the cylindrical portion surrounds the periphery of the terminal unit, the contact between the terminal unit and the bracket can be prevented. For this reason, the insulation of a terminal unit can be improved.
Further, the inner flange portion can function as a pressing plate that presses the terminal unit toward the stator. For this reason, the backlash of the axial direction with respect to the stator of a terminal unit can be suppressed reliably, and the disconnection of the junction part of a terminal unit and a coil can be prevented reliably.

Further, since the outer flange portion is sandwiched between the housing and the bracket, the regulating member is securely fixed in the electric motor without rattling. For this reason, the movement to the axial direction of a terminal unit can be controlled more reliably.
Here, the housing and the bracket are usually formed of a metal whose dimensions can be easily managed. For this reason, even if it is a case where a control member is formed with resin, a control member can be easily arranged in a desired position to a terminal unit. Therefore, it is not necessary to provide a tolerance in consideration of the dimensional variation of the regulating member at the design stage, and as a result, the manufacturing cost can be reduced.

Next, embodiments of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the electric motor 1 includes a stator 3 fitted and fixed to a metal housing 2, and a rotor 4 provided to be rotatable with respect to the stator 3. This is a brushless type motor in which a metal bracket 7 is attached to the opening 27 of the motor, and is used, for example, in a vehicle brake device.

  The housing 2 is formed by integrally molding a bottomed cylindrical yoke body 20 and a bracket housing portion 21 provided at the opening end of the yoke body 20. The stator 3 is fitted and fixed to the peripheral wall 20 </ b> A of the yoke body 20. A bearing 5 is press-fitted into the central portion of the end portion (bottom portion) 20B of the yoke body 20, and the rotating shaft 6 of the rotor 4 is rotatably supported by the bearing 5.

  The diameter of the peripheral wall 21A of the bracket housing portion 21 is set larger than the diameter of the peripheral wall 20A of the yoke body 20, and the metal bracket 7 is fitted and fixed to the peripheral wall 21A. A flange 52 is formed at the opening edge of the bracket housing portion 21. A bolt hole (not shown) is formed in the flange 52, and a bolt (not shown) is screwed into the bolt hole to fasten and fix the housing 2 and the bracket 7.

  The stator 3 has a substantially cylindrical stator core 10. The stator core 10 is formed by laminating a plurality of metal plates (electromagnetic steel plates) 29 punched in a substantially annular shape by pressing in the axial direction, and a plurality of teeth portions 33 for winding the coils 12 are radially formed. Has been. An insulator 11 that is an insulating material is attached to each tooth portion 33 over the entire circumference, and a coil 12 is wound on the insulator 11.

  The insulator 11 has a head portion 61 that comes into contact with both end portions in the longitudinal direction (axial direction) of the tooth portion 33. The head 61 is formed in a substantially U-shaped cross section, and has an extending portion 63A and an extending portion on each of the inner peripheral side (rotor 4 side) and the outer peripheral side (housing 2 side). A portion 63B is formed. The extending portions 63A and 63B extend along the axial direction, and have a substantially arc shape in a plan view from the axial direction.

Further, the height in the axial direction of the extending portion 63B on the outer peripheral side is set to be higher than the height in the axial direction of the extending portion 63A on the inner peripheral side.
Further, a slit 64 is formed in the extending portion 63B. The slit 64 is for pulling out the coil 12 toward the joint portion 36 with the terminal unit 30 described later, and for restricting movement of the terminal unit 30 in the rotation direction.

  The rotor 4 is provided with a permanent magnet 13 at a portion corresponding to the stator 3 of the rotating shaft 6 and a resolver rotor 14A constituting a position detecting resolver 14 on the side opposite to the bearing 5 of the rotating shaft 6. It is. The permanent magnet 13 is attached to the outer peripheral surface of a cylindrical collar 22 that is externally fitted and fixed to the rotary shaft 6, and is magnetized so that the magnetic poles change in order in the circumferential direction.

  The bracket 7 has a stepped cylindrical bracket main body 71, and a fitting cylindrical portion 72 is integrally formed on the bracket main body 71 on the housing 2 side. The fitting cylindrical portion 72 is fitted into the bracket housing portion 21 of the housing 2. Further, the end surface 71 </ b> A on the housing 2 side of the bracket body 71 is a mating surface with the flange 52 of the bracket housing portion 21. And the fitting cylindrical part 72 and end surface 71A of these brackets 7, and the bracket accommodating part 21 of the housing 2 function as a sealing surface, and prevent intrusion of dust from the outside.

  On the other hand, the opening 71 </ b> B on the opposite side to the housing 2 of the bracket body 71 is closed by a disk-shaped plate 73. The plate 73 is for preventing dust from entering from the opening 71B of the bracket body 71, and a through hole 74 through which the rotary shaft 6 passes is formed in the center in the radial direction.

  A housing 15 is formed at the center of the bracket body 71 in the radial direction. A bearing 16 is press-fitted and fixed in the housing 15, and the rotating shaft 6 is rotatably supported by the bearing 16. Further, a resolver stator 14B constituting the resolver 14 is fixed corresponding to the position of the resolver rotor 14A, and the rotational position of the resolver rotor 14A that rotates integrally with the rotary shaft 6 can be detected.

  A hole 31 for drawing an external lead wire 23 into the bracket 7 is formed in the peripheral wall 71 </ b> C of the bracket body 71. A grommet 32 for preventing dust from entering from the outside is inserted into the hole 31. A plate 34 is provided at a portion corresponding to the hole 31 of the peripheral wall 71 </ b> C, and the hole 31 is closed by the grommet 32 and the plate 34. The grommets 32 and the plate 34 are formed with insertion holes 35 and 38 for inserting the lead wires 23, respectively.

  A terminal unit 30 in which a plurality of terminals 28 are arranged is provided on the radially outer side of the housing 15 formed at the radial center of the bracket 7. The terminal unit 30 has a role of electrically connecting the stator winding 17 drawn from the coil 12 on the stator 3 side and the lead wire 23 drawn from the outside, and is connected via the lead wire 23. A current can be supplied to the coil 12 from an external power source. One end of the terminal 28 is connected to the stator winding 17.

  The terminal unit 30 has a plurality of protrusions 37 formed at equal intervals in the circumferential direction toward the stator 3 side. The protrusion 37 is formed so as to correspond to the slit 64 provided in the extending portion 63 </ b> B of the insulator 11. And the protrusion 37 fits into the slit 64 so that the movement of the terminal unit 30 in the rotational direction is restricted.

Further, in the terminal unit 30, a resin-made regulating member 40 is in contact with the upper surface 30A on the side opposite to the insulator 11 side, thereby restricting movement in the axial direction.
As shown in FIGS. 2 to 5, the regulating member 40 has a cylindrical portion 41 formed in a cylindrical shape. The tubular portion 41 is formed so as to surround the terminal unit 30. The outer diameter E1 (see FIGS. 3 and 4) of the cylindrical portion 41 is set so as to substantially match the inner diameter E2 (see FIG. 1) of the bracket 7, whereby the restricting member 40 is fitted to the bracket 7. It is in a combined state.

An outer flange portion 42 is formed at the stator 3 side (lower side in FIG. 3) end of the cylindrical portion 41. The outer flange portion 42 is formed to correspond to the gap between the fitting cylindrical portion 72 of the bracket 7 and the bracket accommodating portion 21 of the housing 2.
That is, as shown in FIG. 4, the dimension T1 in the thickness direction of the outer flange portion 42 is set so as to substantially match the distance T2 between the fitting cylindrical portion 72 and the bracket housing portion 21, and The outer diameter E3 of the outer flange portion 42 is set so as to substantially match the inner diameter E4 (see FIG. 1) of the bracket housing portion 21 of the housing 2. Thus, the outer flange portion 42 is sandwiched between the housing 2 and the bracket 7.
The regulating member 40 may be press-fitted and fixed to the peripheral wall 21A of the bracket housing portion 21 by setting the outer diameter E3 of the outer flange portion 42 to be slightly larger than the inner diameter E4 of the bracket housing portion 21.

  On the other hand, as shown in FIGS. 2 and 3, an inner flange portion 43 is integrally formed on the cylindrical portion 41 of the regulating member 40 on the side opposite to the outer flange portion 42 (upper side in FIG. 3). The inner flange portion 43 is for pressing the terminal unit 30 toward the stator 3 and is formed in a substantially U shape in plan view. The opening 44 formed in the inner flange 43 prevents the interference between the connecting wire 23A for electrically connecting the lead wire 23 and the terminal unit 30, and various sensor wires (not shown) and the regulating member 40. belongs to.

The inner flange portion 43 includes a bulging portion 43A that is continuous with the periphery of the tubular portion 41, and an extending portion 43B that extends radially inward from the bulging portion 43A. The bulging portion 43A bulges toward the opposite side of the outer flange portion 42 (toward the upper side in FIG. 3). The bulging portion 43A can secure a joining space around the joining portion 36 between the stator winding 17 of the coil 12 and the terminal 28, and has a function as a spring.
The extending portion 43B has a function as a pressing plate for pressing the terminal unit 30 toward the stator 3 by contacting the upper surface 30A of the terminal unit 30.

That is, as shown in FIGS. 1 and 5, after the stator 3 and the terminal unit 30 are set in the housing 2, the restriction member 40 is set, and then the bracket 7 is fitted into the bracket accommodating portion 21 of the housing 2. When the restriction member 40 is fixed, the extending portion 43 </ b> B of the restriction member 40 contacts the terminal unit 30.
At this time, the mutual positional relationship between the set position of the extension part 43B and the set position of the terminal unit 30 is set so that the set position of the extension part 43B is slightly lower than the upper surface 30A of the terminal unit 30. . For this reason, the bulging portion 43A is elastically deformed, and the extending portion 43B moves toward the side opposite to the outer flange portion 42 (in the direction of arrow Z in FIG. 5).

  Then, a restoring force due to elastic deformation acts on the bulging portion 43A, and as a result, the inner flange portion 43 presses the terminal unit 30 toward the stator 3 side (insulator 11 side, downward in FIG. 5). Become. The terminal unit 30 is urged toward the stator 3 and is in contact with the extending portion 63B of the insulator 11 (see FIG. 1). As a result, the terminal unit 30 is not only restricted from moving in the axial direction, but is always urged toward the insulator 11 side, so that the terminal unit 30 is integrated with the insulator 11 without rattling. .

  Therefore, according to the above-described embodiment, the movement of the terminal unit 30 in the axial direction can be regulated by the regulating member 40 without performing any processing on the terminal unit 30 or the insulator 11. For this reason, the terminal unit 30 and the insulator 11 (stator 3) can be integrated. In addition, since the inner flange portion 43 of the regulating member 40 presses the terminal unit 30 toward the insulator 11, it is possible to suppress backlash in the axial direction of the terminal unit 30 with respect to the stator 3 (insulator 11).

Therefore, it is possible to prevent the joint portion 36 between the terminal unit 30 and the stator winding 17 on the stator 3 side from being broken due to vibration while reducing the manufacturing cost of the terminal unit 30 and the insulator 11. As a result, it is possible to provide the electric motor 1 that is inexpensive and excellent in vibration resistance.
Moreover, although the method of preventing the backlash with respect to the insulator 11 of the terminal unit 30 by adhere | attaching both using an adhesive agent etc. is also considered, it can prevent the backlash of the terminal unit 30 more easily than managing the adhesion | attachment process. Can do.

  Furthermore, according to the above-described embodiment, rattling in the axial direction of the regulating member 40 can be prevented by sandwiching the outer flange portion 42 of the regulating member 40 between the housing 2 and the bracket 7. In addition to this, the outer flange portion 42 is press-fitted and fixed to the peripheral wall 21 </ b> A of the bracket housing portion 21, and / or the cylindrical portion 41 of the restriction member 40 is fitted and fixed to the bracket 7, so that the restriction member 40 extends in the radial direction. It is possible to prevent rattling. For this reason, the regulating member 40 is securely fixed in the electric motor 1 without rattling. Therefore, the terminal unit 30 can be held more reliably.

  Since the housing 2 and the bracket 7 are formed of a metal whose dimensions are easy to manage, even if the restricting member 40 is formed of a resin whose dimensions are difficult to control, the restricting member 40 is located at a desired position with respect to the terminal unit 30. Can be easily arranged. For this reason, it is not necessary to provide a tolerance considering the dimensional variation of the regulating member 40 at the design stage, and as a result, it is possible to reduce the manufacturing cost.

  Further, according to the above-described embodiment, the tubular portion 41 of the restricting member 40 is formed so as to surround the terminal unit 30. For this reason, it can prevent that the junction part 36 of the terminal 28 of the terminal unit 30 and the stator coil | winding 17 by the side of the stator 3 contacts the bracket 7 directly, and can improve insulation.

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 used for the brake device for vehicles, it is not restricted to this.

  Furthermore, in the above-described embodiment, the case where the backlash of the regulating member 40 in the axial direction is prevented by sandwiching the outer flange portion 42 of the regulating member 40 between the housing 2 and the bracket 7 has been described. However, the present invention is not limited to this, and for example, by providing a wave washer or the like between the outer flange portion 42 and the bottom wall 21B of the bracket housing portion 21 (see FIG. 4), rattling in the axial direction of the restricting member 40 is performed. May be prevented.

  That is, for example, the dimension T1 (see FIG. 3) in the thickness direction of the outer flange portion 42 is smaller than the distance T2 (see FIG. 4) between the fitting cylindrical portion 72 and the bracket housing portion 21 due to a molding error. Even in such a case, it is possible to absorb a dimensional error in the axial direction of the outer flange portion 42 of the regulating member 40 by a wave washer or the like. For this reason, the regulating member 40 can be more reliably fixed in the electric motor 1.

It is a longitudinal cross-sectional view of the electric motor in embodiment of this invention. It is a top view of the regulating member in the embodiment of the present invention. It is a partial cross section figure of the regulating member in the embodiment of the present invention. It is the X section enlarged view of FIG. It is the Y section enlarged view of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electric motor 2 Housing 3 Stator 4 Rotor 7 Bracket 12 Coil 27 Opening part 30 Terminal unit 40 Restriction member 41 Cylindrical part 42 Outer flange part 43 Inner flange part

Claims (2)

A housing having an opening, a stator fixed in the housing and wound with a coil, a rotor rotatably supported inside the stator, and a bracket attached to the opening of the housing; In an electric motor comprising a terminal unit electrically connected to the coil,
An electric motor comprising a restriction member that presses and holds the terminal unit toward the stator via the bracket.   The regulating member has a cylindrical portion surrounding the terminal unit, and an inner flange portion that presses the terminal unit toward the stator is formed on one end side of the cylindrical portion. The electric motor according to claim 1, wherein an outer flange portion sandwiched between the housing and the bracket is formed on an end side.

Images