JP2017225239A - Motor housing, motor, and motor with reduction gear - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively suppress the occurrence of undesired noise by suppressing the resonance of a bottom part of a second motor case.SOLUTION: A motor housing 5 comprises: a first motor case 6 and a second motor case 7 which are constructed so as to be dividable in an axial direction. The first motor case 6 houses a stator 8 and a rotor 9. The second motor case 7 comprises: a cylindrical peripheral wall part 14 to which one end is coupled to the first motor case 6; and a bottom part 13 that closes the other end of the peripheral wall part 14. An angle part 100 as a boundary part of the peripheral wall part 14 and the bottom part 13 is thicker than the peripheral wall part 14 and the bottom part 13.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a motor housing, a motor, and a motor with a reduction gear.

  Some motors include a motor housing, a stator that is fitted and fixed in the motor housing, and a rotor that is rotatably provided to the stator. A plurality of coils are wound around the stator. Then, electric power is selectively supplied to each coil by the controller board. On the other hand, a permanent magnet is provided on the outer peripheral surface of the rotor. Under such a configuration, when electric power is supplied to the coil, a magnetic field is formed in the stator, and a magnetic attractive force or repulsive force is generated between the magnetic field and the permanent magnet. Thereby, a rotor rotates continuously.

  By the way, as disclosed in Patent Document 1, for example, there is a motor having a motor housing in which a motor case housing a stator and a rotor and a casing (fan cowl) separate from the motor case are coupled.

JP 2008-92797 A

  In a configuration having a motor housing divided into a plurality of parts as disclosed in Patent Document 1, when the motor is operated, vibration due to rotation of the rotor is transmitted to the casing through the motor case, and the casing resonates. There is a problem of generating noise and the like. In particular, when the casing includes a cylindrical wall portion whose one end is connected to the motor case and a bottom plate that closes the other end of the cylindrical wall portion, the bottom plate vibrates like a drum film and noise increases. Sometimes.

  Therefore, the present invention has been made in view of the above-described circumstances, and provides a motor housing, a motor, and a motor with a speed reducer that can effectively suppress the generation of noise.

The present invention employs the following means in order to solve the above problems.
That is, the motor housing of the present invention includes a motor case that can accommodate a stator and a rotor, and the motor case includes a cylindrical peripheral wall portion and a bottom portion that closes one end of the peripheral wall portion, and the peripheral wall. A corner portion, which is a boundary portion between the portion and the bottom portion, is formed to be thicker than the peripheral wall portion and the bottom portion.

  It is preferable that the corner portion has a radius of curvature on the inner peripheral surface side of the motor case larger than a radius of curvature on the outer peripheral surface side of the motor case.

  The motor case includes a first motor case and a second motor case configured to be split in an axial direction, the first motor case can accommodate the stator and the rotor, and the second motor case includes: You may have the said surrounding wall part by which one end is connected with the said 1st motor case, and the said bottom part.

According to such a configuration, the rigidity of the bottom portion of the motor case is increased, and vibration and noise can be reduced. In particular, when the motor case is constituted by the first motor case and the second motor case that can be divided in the axial direction, the corner portions of the peripheral wall portion and the bottom portion of the second motor case are formed thick, When vibration is transmitted through the first motor case when the motor accommodated in the first motor case is operated, it is possible to prevent the bottom portion of the second motor case from resonating.
Further, by making the curvature radius on the inner peripheral surface side larger than the curvature radius on the outer peripheral surface side of the corner portion, the corner portion can be formed thicker than the peripheral wall portion and the bottom portion. Further, by forming the corner portion with a curved surface, it is possible to suppress stress due to vibration from being concentrated on the corner portion.

  In addition, the present invention includes a motor case that can accommodate a stator and a rotor, and the motor case includes a cylindrical peripheral wall portion and a bottom portion that closes one end of the peripheral wall portion, and the motor at the bottom portion. A rib extending in the radial direction of the bottom portion protrudes on the outer peripheral surface side of the case.

  The motor case includes a first motor case and a second motor case configured to be split in an axial direction, the first motor case can accommodate the stator and the rotor, and the second motor case includes: You may have the said surrounding wall part by which one end is connected with the said 1st motor case, and the said bottom part.

  According to such a configuration, the rigidity of the bottom portion of the motor case is increased, and vibration and noise can be reduced. In particular, when the motor case is constituted by a first motor case and a second motor case that can be divided in the axial direction, the operation of the motor accommodated in the first motor case is provided by providing a rib extending in the radial direction at the bottom. It is possible to prevent the bottom portion of the second motor case from resonating when the vibration generated by the above is transmitted through the first motor case.

  Further, according to the present invention, the first motor case and the second motor case are connected by a plurality of fastening portions spaced in the circumferential direction, and the ribs are disposed symmetrically with respect to the center of the bottom portion. Alternatively, it may be formed extending in a direction orthogonal to the direction connecting the two fastening portions.

  According to such a configuration, the strength of the bottom portion of the second motor case can be reliably increased, and the resonance of the bottom portion can be effectively suppressed.

  The motor according to the present invention includes the motor housing as described above, the stator that is fitted and fixed to the motor housing, the coil is wound around, the rotor that is rotatably supported by the motor housing, and the stator. And a rotor provided to be rotatable with respect to the stator on the radially inner side.

  According to the motor having such a configuration, generation of noise can be effectively suppressed.

  A motor with a speed reducer according to the present invention includes the motor as described above and a speed reducing unit that decelerates and outputs the rotation of the rotor of the motor.

  According to the motor with a speed reducer having such a configuration, generation of noise can be effectively suppressed.

  According to the present invention, the rigidity of the bottom portion of the motor case is increased, and vibration and noise can be reduced. In particular, when the motor case is constituted by the first motor case and the second motor case that can be divided in the axial direction, the corner portions of the peripheral wall portion and the bottom portion of the second motor case are formed thick, When vibration is transmitted through the first motor case when the motor accommodated in the first motor case is operated, it is possible to prevent the bottom portion of the second motor case from resonating.

It is a perspective view of the motor with a reduction gear in the 1st Embodiment of this invention. It is sectional drawing which follows the AA line of FIG. It is a perspective sectional view of the 2nd motor case which constitutes a motor with a reduction gear. It is a perspective view of a stator. It is sectional drawing which follows the EE line | wire of FIG. It is a perspective view of the 2nd motor case which comprises the motor with a reduction gear in the 2nd Embodiment of this invention. It is a figure which shows the natural vibration value analysis result in an Example.

  Next, a first embodiment of the present invention will be described with reference to the drawings.

(First embodiment)
1 is a perspective view of a motor 1 with a speed reducer, and FIG. 2 is a cross-sectional view taken along line AA of FIG.
(Motor with reduction gear)
As shown in FIGS. 1 and 2, the motor 1 with a speed reducer serves as a drive source for electrical components (for example, a power window, a sunroof, an electric seat, etc.) mounted on a vehicle, for example. The motor 1 with a speed reducer includes a motor unit (motor) 2, a deceleration unit 3 that decelerates and outputs the rotation of the motor unit 2, and a controller unit 4 that performs drive control of the motor unit 2. In the following description, the simple axial direction refers to the axial direction of the rotating shaft 31 of the motor unit 2, the simple circumferential direction refers to the circumferential direction of the rotating shaft 31, and simply refers to the radial direction. The radial direction of the rotating shaft 31 shall be said.

(Motor part)
The motor unit 2 includes a motor housing 5, a substantially cylindrical stator 8 housed in the motor housing 5, and a rotor 9 provided on the radially inner side of the stator 8 and rotatable with respect to the stator 8. It is equipped with.

(Motor case)
The motor housing 5 is formed of a material having excellent heat dissipation, such as aluminum die casting. The motor housing 5 includes a first motor case 6 and a second motor case 7 that are configured to be separable in the axial direction. The first motor case 6 and the second motor case 7 are each formed in a bottomed cylindrical shape, and the motor housing 5 having an internal space is formed by fitting the respective openings 6a and 7a.

More specifically, the first motor case 6 is integrally formed with the gear case 40 by joining the bottom portion 10 to the gear case 40 of the speed reduction portion 3. A through-hole 10 a through which the rotation shaft 31 of the rotor 9 can be inserted is formed at a substantially central portion of the bottom portion 10 in the radial direction.
Further, on the inner peripheral surface of the first motor case 6, a stator internal fitting portion 18 having a diameter increased by a step is formed between the opening 6 a and the substantially axial center. The outer peripheral surface of the stator 8 is fitted to the stator inner fitting portion 18. Further, a protruding strip portion 12 is provided on the outer peripheral surface of the peripheral wall portion 11 of the first motor case 6 so as to project over the entire periphery on the opening 6a side. An opening 7 a of the second motor case 7 is fitted to the ridge 12.

FIG. 3 is a perspective sectional view of the second motor case 7 constituting the motor 1 with a speed reducer.
As shown in FIGS. 2 and 3, the second motor case 7 is made of resin and has a cylindrical peripheral wall portion 14 having one end coupled to the first motor case 6 and a bottom portion that closes the other end of the peripheral wall portion 14. 13 and a bottomed cylindrical shape integrally provided.

  As shown in FIG. 3, in the second motor case 7, the corner portion 100 that is the boundary portion between the peripheral wall portion 14 and the bottom portion 13 is thicker than the thickness t1 of the peripheral wall portion 14 and the thickness t2 of the bottom portion 13. It is formed so that t3 becomes large. More specifically, in the corner portion 100, the outer peripheral surface 100a and the inner peripheral surface 100b of the second motor case 7 are respectively formed by curved surfaces, and the curvature of the inner peripheral surface 100b is larger than the curvature radius r1 of the outer peripheral surface 100a. The radius r2 is formed to be larger.

An inner diameter D <b> 2 of the peripheral wall portion 14 is set larger than an inner diameter D <b> 1 of the stator inner fitting portion 18 formed in the first motor case 6.
The fitting portion 15 is formed on the peripheral edge of the opening 7 a at one end of the peripheral wall portion 14 and is fitted to the ridge portion 12 of the first motor case 6. The fitting portion 15 is formed by integrating a first diameter-expanded portion 16 having a diameter increased from the peripheral wall portion 14 by a step and a second diameter-expanded portion 17 having a diameter increased from the first diameter-expanded portion 16 by a step. It is molded. Then, the ridge 12 of the first motor case 6 is fitted into the second enlarged diameter portion 17.

  Flange portions (fastening portions) 12 f and 15 f extending outward in the radial direction are formed on the outer peripheral surfaces of the protruding strip portion 12 of the first motor case 6 and the fitting portion 15 of the second motor case 7. These flange portions 12f and 15f are provided at, for example, two positions, that is, symmetrical positions sandwiching the center of the bottom portion 13 of the second motor case 7 at intervals in the circumferential direction. Each flange portion 12f of the first motor case 6 and the flange portion 15f of the second motor case 7 are fastened with screws 19 in a state where they are overlapped with each other.

  The relative position in the axial direction between the first motor case 6 and the second motor case 7 is determined by the end surface 12a of the ridge 12 contacting the stepped surface 17a of the second enlarged diameter portion 17. On the other hand, the first enlarged diameter portion 16 is formed so as to avoid contact with the tip side (opening edge side) of the first motor case 6 with respect to the ridge portion 12.

(Stator)
FIG. 4 is a perspective view of the stator 8.
As shown in FIGS. 2 and 4, the stator 8 fitted in the stator inner fitting portion 18 is formed in a substantially cylindrical shape and has a core portion 21 that forms a magnetic path, and radially inward from the stator core 20. A plurality of teeth 22 projecting toward each other has a stator core 20 integrally formed. The stator core 20 is formed by laminating a plurality of metal plates in the axial direction. The stator core 20 is not limited to the case where a plurality of metal plates are laminated in the axial direction, and may be formed, for example, by press-molding soft magnetic powder. The outer peripheral surface of the core portion 21 of the stator core 20 formed as described above is fitted into the stator inner fitting portion 18 of the first motor case 6.

  Here, as shown in FIG. 2, the inner diameter D <b> 2 of the peripheral wall portion 14 in the second motor case 7 is set larger than the inner diameter D <b> 1 of the stator inner fitting portion 18 formed in the first motor case 6. A gap S <b> 1 is formed between the inner peripheral surface of the peripheral wall portion 14 and the outer peripheral surface of the core portion 21.

As shown in FIGS. 2 and 4, a resin insulator 23 is attached to the teeth 22 of the stator core 20 so as to cover the periphery of the teeth 22.
The insulator 23 includes a bottom 23a covering the periphery of the teeth 22, an outer peripheral wall 23b erected on the radially outer side of the bottom 23a (a base end side (radially outer side) of the teeth 22), and a radially inner side of the bottom 23a ( An inner peripheral wall 23c erected on the tip side (radially inner side) of the tooth 22 is integrally formed.
A coil 24 is wound around each of the teeth 22 from above the insulator 23 configured as described above. Each coil 24 generates a magnetic field for rotating the rotor 9 by power feeding from the controller unit 4.

(Rotor)
As shown in FIG. 2, the rotor 9 provided so as to be rotatable with respect to the stator 8 is fitted to the rotary shaft 31, the columnar rotor core 32 that is externally fixed to the rotary shaft 31, and the outer peripheral surface of the rotor core 32. And a ring-shaped magnet 33 to be combined.

  The rotating shaft 31 is integrally formed with the worm shaft 44 that constitutes the speed reducing portion 3. The rotor core 32 is formed by laminating a plurality of metal plates in the axial direction. The rotor core 32 is not limited to the case where a plurality of metal plates are laminated in the axial direction, and may be formed, for example, by press-molding soft magnetic powder.

  A through hole 32 a penetrating in the axial direction is formed at the substantially center in the radial direction of the rotor core 32. The rotary shaft 31 is press-fitted into the through hole 32a. Alternatively, the rotary shaft 31 may be inserted into the through hole 32a, and the rotor core 32 may be externally fixed to the rotary shaft 31 using an adhesive or the like.

  The magnet 33 fitted to the outer peripheral surface of the rotor core 32 is magnetized so that a plurality of magnetic poles are formed in order in the circumferential direction. For example, in this embodiment, the magnet 33 is magnetized to four poles. The magnetic poles of the magnet 33 are skewed so as to be twisted (tilted) with respect to the axial direction.

(Decelerator)
FIG. 5 is a cross-sectional view taken along line EE in FIG.
As shown in FIGS. 1 and 5, the speed reduction unit 3 includes a gear case 40 to which the motor housing 5 is attached, and a worm speed reduction mechanism 41 accommodated in the gear case 40. The gear case 40 is made of a material with excellent heat dissipation, such as aluminum die cast. The gear case 40 is formed in a box shape having an opening 40a on one surface, and has a gear housing portion 42 for housing the worm reduction mechanism 41 therein. The side wall 40b of the gear case 40 is formed with an opening 43 that communicates the through hole 10a of the first motor case 6 and the gear housing portion 42 at a location where the first motor case 6 is integrally formed. Yes.

  Further, as shown in FIG. 1, three fixing brackets 54 a, 54 b, 54 c are integrally formed on the side wall 40 b of the gear case 40. These fixing brackets 54a, 54b and 54c are for fixing the motor 1 with a speed reducer to a vehicle body (not shown) or the like. The three fixing brackets 54a, 54b, 54c are arranged at substantially equal intervals in the circumferential direction so as to avoid the motor unit 2. Anti-vibration rubber 55 is attached to each of the fixed brackets 54a, 54b, 54c. The anti-vibration rubber 55 is for preventing vibrations when driving the motor 1 with a speed reducer from being transmitted to a vehicle body (not shown).

Further, a substantially cylindrical bearing boss 49 projects from the bottom wall 40 c of the gear case 40.
The bearing boss 49 is for rotatably supporting the output shaft 48 of the worm reduction mechanism 41, and a sliding bearing 50 is provided on the inner peripheral surface. Further, as shown in FIG. 5, an O-ring 51 is attached to the inner peripheral edge of the tip of the bearing boss 49. This prevents dust and water from entering from the outside to the inside via the bearing boss 49. A plurality of ribs 52 are provided on the outer peripheral surface of the bearing boss 49. Thereby, the rigidity of the bearing boss 49 is ensured.

  The worm speed reduction mechanism 41 housed in the gear housing portion 42 includes a worm shaft 44 and a worm wheel 45 that meshes with the worm shaft 44. The worm shaft 44 is disposed coaxially with the rotation shaft 31 of the motor unit 2. As shown in FIG. 2, the worm shaft 44 is rotatably supported by bearings 46 and 47 provided at both ends of the gear case 40. The end of the worm shaft 44 on the motor unit 2 side protrudes to the opening 43 of the gear case 40 through the bearing 46. The projecting end of the worm shaft 44 and the end of the rotating shaft 31 of the motor unit 2 are joined together so that the worm shaft 44 and the rotating shaft 31 are integrated.

  As shown in FIG. 5, the worm wheel 45 meshed with the worm shaft 44 is provided with an output shaft 48 at the radial center of the worm wheel 45. The output shaft 48 is arranged coaxially with the rotation axis direction of the worm wheel 45. As shown in FIG. 1, the output shaft 48 protrudes outside the gear case 40 through a bearing boss 49 of the gear case 40. A spline 48 a that can be connected to an electrical component (not shown) is formed at the protruding tip of the output shaft 48.

  As shown in FIG. 5, a sensor magnet 53 is provided at the center in the radial direction of the worm wheel 45 on the side opposite to the side from which the output shaft 48 protrudes. The sensor magnet 53 constitutes one of rotational position detectors 60 that detect the rotational position of the worm wheel 45. The magnetic detection element 61 that constitutes the other of the rotational position detection unit 60 is provided in the controller unit 4 that is disposed opposite to the worm wheel 45 on the sensor magnet 53 side (opening 40a side of the gear case 40) of the worm wheel 45. ing.

(Controller part)
The controller unit 4 that controls the drive of the motor unit 2 includes a controller board 62 on which the magnetic detection element 61 is mounted, and a cover 63 provided so as to close the opening 40a of the gear case 40. And the controller board | substrate 62 is opposingly arranged by the sensor magnet 53 side (opening 40a side of the gear case 40) of the worm wheel 45. As shown in FIG.

  The controller board 62 is obtained by forming a plurality of conductive patterns (not shown) on a so-called epoxy board. The controller board 62 is formed in a rectangular shape that is long in the direction orthogonal to the worm shaft 44 (left and right direction in FIG. 5). The magnetic detection element 61 is mounted on the one surface 62 a of the controller board 62 on the worm wheel 45 side and at a position corresponding to the sensor magnet 53 of the output shaft 48.

  The controller board 62 is connected to the terminal portion of the coil 24 drawn from the stator core 20 of the motor unit 2, and the terminal 64 a (see FIG. 1) of the connector 64 provided on the cover 63 is electrically connected. It is connected. Further, on the other surface 62b opposite to the one surface 62a of the controller board 62 (on the opening 40a side of the gear case 40), switching such as an FET (Field Effect Transistor) for controlling the current supplied to the coil 24 is performed. A capacitor and the like for smoothing the voltage applied to the power module 65 made of elements and the controller board 62 are mounted.

  A heat conduction plate 67 is attached to the power module 65 via a controller-side first heat dissipation sheet 66. The heat conduction plate 67 is formed in a strip shape and a crank shape in cross section so as to be long along the longitudinal direction (left and right direction in FIG. 54) of the controller substrate 62. That is, the heat conducting plate 67 is connected to the worm speed reduction mechanism 41 side from the end of the plate main body 68 disposed on the power module 65 and the side of the plate main body 68 where the worm speed reduction mechanism 41 is disposed (left side in FIG. 10). After being bent to the lower side in FIG. 5, the sub plate 69 further extends so as to be parallel to the plate body 68.

The width of the plate body 68 in the short direction is set to such a size that the entire upper surface of the power module 65 is covered by the plate body 68.
On the other hand, the sub plate 69 is formed so that the tip (the side opposite to the plate main body 68) protrudes from the end of the controller board 62. Further, the tip of the sub plate 69 extends to the end of the side wall 40 b of the gear case 40. Then, at the tip of the sub plate 69, one surface 69 a on the controller board 62 (worm reduction mechanism 41) side is in contact with the side wall 40 b of the gear case 40 via the controller side second heat radiating sheet 71.

The cover 63 covering the controller board 62 and the heat conducting plate 67 configured in this manner is made of resin and is formed so as to bulge slightly outward. The inner surface side of the cover 63 serves as a controller housing portion 56 that houses the controller board 62 and the heat conduction plate 67.
As shown in detail in FIG. 1, a connector 64 is integrally formed on the outer periphery of the cover 63. The connector 64 is formed so as to be fitted with a connector extending from an external power source (not shown). The terminal 64 a of the connector 64 extends in and out of the connector 64. The inner end of the terminal 64a is electrically connected to the controller board 62. As a result, the power of the external power supply is supplied to the controller board 62.

  Further, a fitting portion 81 that is fitted to the end portion of the side wall 40 b of the gear case 40 is formed to project from the opening edge of the cover 63. The fitting portion 81 is configured by two walls 81 a and 81 b along the opening edge of the cover 63. And the edge part of the side wall 40b of the gear case 40 is inserted (fitted) between these two walls 81a and 81b. As a result, a labyrinth portion 83 is formed between the gear case 40 and the cover 63. The labyrinth 83 prevents dust and water from entering between the gear case 40 and the cover 63. The gear case 40 and the cover 63 are fixed by fastening a bolt (not shown).

(Operation of motor with reduction gear)
Next, operation | movement of the motor 1 with a reduction gear is demonstrated.
In the motor 1 with a speed reducer, the power supplied to the controller board 62 via the connector 64 is selectively supplied to each coil 24 of the motor unit 2 via the power module 65. Then, a predetermined magnetic field is formed in the stator 8 (the teeth 22), and a magnetic attractive force and a repulsive force are generated between the magnetic field and the magnet 33 of the rotor 9. Thereby, the rotor 9 rotates continuously.
When the rotor 9 rotates, the worm shaft 44 integrated with the rotating shaft 31 rotates, and further the worm wheel 45 meshed with the worm shaft 44 rotates. Then, the output shaft 48 connected to the worm wheel 45 rotates to drive a desired electrical component.

  Further, the rotational position detection result of the worm wheel 45 detected by the magnetic detection element 61 mounted on the controller board 62 is output as a signal to an external device (not shown) via the connector 64. An external device (not shown) outputs a drive signal for the power module 65 based on the rotational position detection signal for the worm wheel 45. Thereby, the switching timing of the switching element of the power module 65 is controlled, and the drive control of the motor unit 2 is performed.

  Thus, in the above-described first embodiment, the corner portion 100 between the peripheral wall portion 14 and the bottom portion 13 of the second motor case 7 is formed thick. For this reason, the rigidity of the bottom part 13 can be improved. In addition, when the motor unit 2 accommodated in the first motor case 6 is operated, vibration is transmitted through the first motor case 6 to suppress the bottom 13 of the second motor case 7 from resonating. Can do. Therefore, it is possible to effectively suppress the generation of noise during the operation of the motor 1 with speed reducer.

  Further, the second motor case 7 makes the corner portion 100 easier than the peripheral wall portion 14 and the bottom portion 13 by making the curvature radius r2 on the inner peripheral surface 100b side larger than the curvature radius r1 on the outer peripheral surface 100a side of the corner portion 100. It can be formed thick. Further, by forming the corner portion 100 with a curved surface, it is possible to suppress stress due to vibration from being concentrated on the corner portion 100.

(Second Embodiment)
Next, a second embodiment of a motor housing, a motor, and a motor with a reduction gear according to the present invention will be described. Note that in the second embodiment described below, the same reference numerals are given to the same components as in the first embodiment, and description thereof will be omitted.
FIG. 6 is a perspective view of a second motor case 7 constituting the motor 1 with a speed reducer in the second embodiment of the present invention.

  As shown in FIG. 6, in the present embodiment, the second motor case 7B is made of resin, and has a cylindrical peripheral wall portion 14 having one end coupled to the first motor case 6 (see FIG. 1), and the peripheral wall portion. The bottom part 13 which obstruct | occludes the other end of 14 has comprised the bottomed cylinder shape provided integrally.

  On the outer peripheral surface of the fitting portion 15 of the second motor case 7B, a flange portion 15f extending radially outwardly sandwiches the two portions, that is, the center of the bottom portion 13 of the second motor case 7 at intervals in the circumferential direction. It is provided at a symmetrical position. The flange portion 15f of the second motor case 7 is fastened to each flange portion 12f (see FIG. 1) of the first motor case 6 by screws 19 (see FIG. 1).

  In such a second motor case 7B, a rib 110 extending in the radial direction of the bottom portion 13 is formed on the bottom portion 13 so as to protrude from the outer surface 13f of the bottom portion 13. The rib 110 extends in a direction orthogonal to the direction connecting the two flange portions 12 f and 12 f that are the fastening portions with the first motor case 6 at the bottom portion 13. The rib 110 has a length substantially equal to the diameter of the bottom portion 13 in the direction orthogonal to the direction connecting the flange portions 12f and 12f, and is formed over the entire radial direction of the bottom portion 13. The rib 110 preferably has a width dimension in a direction connecting the flange portions 12f and 12f, for example, about 1/3 of the diameter of the bottom portion 13.

  Thus, in the above-described second embodiment, the rib 110 extending in the radial direction of the bottom portion 13 of the second motor case 7B is provided. For this reason, the rigidity of the bottom part 13 can be improved. In addition, when the motor unit 2 accommodated in the first motor case 6 is operated, vibration is transmitted through the first motor case 6 to suppress the bottom 13 of the second motor case 7 from resonating. Can do.

  In addition, the rib 110 is formed to extend in a direction orthogonal to the direction connecting the two fastening portions arranged symmetrically with respect to the center of the bottom portion 13. According to such a configuration, the strength of the bottom portion 13 of the second motor case 7 can be reliably increased, and the resonance of the bottom portion 13 can be effectively suppressed.

(Modification of this embodiment)
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.
For example, in the above-described embodiment, the case where the motor 1 with a reduction gear is a drive source for electrical components (for example, a power window, a sunroof, an electric seat, etc.) mounted on the vehicle has been described. However, it is not restricted to this, The motor 1 with a reduction gear can be used for various uses.

  In the above-described embodiment, the motor housing 5 includes the first motor case 6 and the second motor case 7 that are configured to be divided in the axial direction. The first motor case 6 includes the stator 8 and the rotor 9. The case where is accommodated was explained. However, the present invention is not limited to this, and the first motor case 6 and the second motor case 7 may be integrated to form one motor case.

  In addition to this, the configuration described in the above embodiment can be selected or changed to another configuration as appropriate without departing from the gist of the present invention.

In addition, since the natural vibration value analysis was performed about the 2nd motor cases 7 and 7B of the structure shown by the said 1st, 2nd embodiment, the result is shown below.
In the second motor case 7 having the configuration shown in the first embodiment, the thickness t1 of the peripheral wall portion 14 is set to 1.5 mm, the thickness t2 of the bottom portion 13 is set to 1.0 mm, and the outer peripheral surface of the corner portion 100 is set. The curvature radius r1 on the 100a side was set to 3.0 mm, and the curvature radius r2 on the inner peripheral surface 100b side was set to 5.3 mm (Example 1).
In the second motor case 7B having the configuration shown in the second embodiment, the thickness t1 of the peripheral wall portion 14 is set to 1.5 mm, the thickness t2 of the bottom portion 13 is set to 1.0 mm, and the height of the rib 110 is set. The width of the rib 110 was set to 2 mm and 16 mm (Example 2).
For comparison, a motor case without the rib 110 and having a radius of curvature r2 on the inner peripheral surface 100b side smaller than the radius of curvature r1 on the outer peripheral surface 100a side was prepared (comparative example). In the motor case of this comparative example, the thickness t1 of the peripheral wall portion 14 is set to 1.5 mm, the thickness t2 of the bottom portion 13 is set to 1.0 mm, and the curvature radius r1 on the outer peripheral surface 100a side of the corner portion 100 is set to 3.0 mm. The curvature radius r2 on the inner peripheral surface 100b side was set to 2.0 mm.

For the motor cases of Examples 1 and 2 and Comparative Example, the natural vibration value analysis was performed in terms of frequency.
FIG. 7 shows the result.
As shown in FIG. 7, the motor case 7 of the first embodiment in which the curvature radius r2 of the inner peripheral surface 100b of the corner portion 100 is increased, and the motor case 7B of the second embodiment having the rib 110 have these configurations. It was confirmed that the response acceleration was lower in the vibration mode at frequencies of 1500 Hz and 2050 Hz than in the comparative example.

DESCRIPTION OF SYMBOLS 1 ... Motor with reduction gear 2 ... Motor part (motor)
DESCRIPTION OF SYMBOLS 3 ... Deceleration part 5 ... Motor housing 6 ... 1st motor case 7, 7B ... 2nd motor case 8 ... Stator 9 ... Rotor 13 ... Bottom part 14 ... Peripheral wall part 12f, 15f ... Flange part (fastening part)
24 ... Coil 100 ... Corner 100a ... Outer peripheral surface 100b ... Inner peripheral surface 110 ... Ribs r1, r2 ... Curvature radii t1, t2 ... Thickness

Claims (8)

A motor case that can accommodate the stator and rotor,
The motor case includes a cylindrical peripheral wall portion and a bottom portion that closes one end of the peripheral wall portion, and a corner portion that is a boundary portion between the peripheral wall portion and the bottom portion is formed from the peripheral wall portion and the bottom portion. The motor housing is also formed with a thick wall.   2. The motor housing according to claim 1, wherein the corner portion has a radius of curvature on the inner peripheral surface side of the motor case larger than a radius of curvature on the outer peripheral surface side of the motor case. The motor case is composed of a first motor case and a second motor case configured to be separable in the axial direction,
The first motor case can accommodate the stator and the rotor,
3. The motor housing according to claim 1, wherein the second motor case includes the peripheral wall portion, one end of which is connected to the first motor case, and the bottom portion. A motor case that can accommodate the stator and rotor,
The motor case includes a cylindrical peripheral wall portion and a bottom portion that closes one end of the peripheral wall portion, and a rib extending in a radial direction of the bottom portion projects from the outer peripheral surface side of the motor case at the bottom portion. A motor housing characterized by being made. The motor case is composed of a first motor case and a second motor case configured to be separable in the axial direction,
The first motor case can accommodate the stator and the rotor,
5. The motor housing according to claim 4, wherein the second motor case includes the peripheral wall portion, one end of which is connected to the first motor case, and the bottom portion. The first motor case and the second motor case are connected by a plurality of fastening portions spaced in the circumferential direction,
The motor housing according to claim 5, wherein the rib is formed to extend in a direction orthogonal to a direction connecting two fastening portions arranged symmetrically with respect to a center of the bottom portion. The motor housing according to any one of claims 1 to 6,
The stator that is fitted and fixed to the motor housing, and the coil is wound around;
A rotor that is rotatably supported by the motor housing and that is rotatably provided to the stator on the radially inner side of the stator;
A motor comprising: A motor according to claim 7;
A speed reducer that decelerates and outputs the rotation of the rotor of the motor;
A motor with a speed reducer.

Images