JP6527776B2 - Motor device - Google Patents

Description

  The present invention relates to a motor device suitable for use as a drive source of various devices mounted on a vehicle.

  In vehicles such as automobiles, various devices such as a power window device and a power seat device are mounted, and a drive source of these devices is a motor having a motor operated by a power supply such as a battery mounted in the vehicle. Devices are often used. Most of such motor devices include a reduction mechanism for reducing the rotation of the motor in addition to the motor, and the reduction mechanism is accommodated in a case integrated with the motor. More specifically, the case is provided with a gear accommodating portion, and at least one of the plurality of gears constituting the speed reduction mechanism is rotatably accommodated in the gear accommodating portion (Patent Document 1).

JP 2012-70564 A

  The gear housed in the gear housing rotates while in contact with the inner surface of the gear housing. For example, the gear is placed at the bottom of the gear housing and rotates while in contact with the bottom inner surface. For this reason, if the sliding resistance between the gear and the inner surface of the gear housing is large, the sliding portion may be worn or abnormal noise may be generated from the sliding portion, and the durability and reliability of the motor device may be reduced. Do. Furthermore, in order to reduce sliding resistance, grease may be applied to the sliding part, but grease breakage may occur in a short period of time.

  An object of the present invention is to reduce the sliding resistance between a gear and a gear housing, and to improve the durability and reliability of a motor device.

  The motor device according to the present invention comprises a motor, a reduction mechanism for reducing the rotation of the motor, a gear case for accommodating the reduction mechanism, and a gear provided on the gear case for rotatably accommodating the gears constituting the reduction mechanism. The housing portion has a plurality of sliding contact projections provided on the inner surface of the gear housing portion and in sliding contact with the gear, and the plurality of sliding contact projections are circles of a circle centered on the rotation axis of the gear. They are arranged at predetermined intervals on the circumference.

  In one aspect of the present invention, the gear housing portion has a bottom facing the side surface of the gear, and a side wall rising from the bottom to surround the gear, and the sliding protrusion is an inner surface of the bottom Provided in

  In another aspect of the present invention, a recess for holding grease is formed on the end face of the sliding contact protrusion.

  In another aspect of the present invention, the plurality of sliding projections are arranged at equal intervals.

  In another aspect of the present invention, the gear is provided with an annular sliding contact ring portion, and the sliding contact protrusion is in sliding contact with the sliding contact ring portion.

  In another aspect of the present invention, an end face of the sliding ring portion slidingly contacting the sliding protrusion is a circular arc surface.

  In another aspect of the present invention, the speed reduction mechanism includes a plurality of gears, and the gear in sliding contact with the sliding projections is a gear of the final stage of the speed reduction mechanism.

  In another aspect of the present invention, the gear storage portion is continuous with a first bottom portion on which the gear of the final stage is mounted, and a step portion at the first bottom portion, and a gear just before the gear of the final stage And the sliding contact protrusion is provided on the inner surface of the first bottom portion in a region avoiding the step portion.

  According to the present invention, a highly durable and reliable motor device is realized in which the sliding resistance between the gear and the gear housing portion is reduced.

FIG. 1 is a schematic view showing an automobile equipped with a motor device for seat position adjustment. It is a top view of a motor apparatus. It is a disassembled perspective view which shows the internal structure of a motor apparatus. It is a partially expanded perspective view which shows an engagement convex part and an engagement recessed part. It is a partial expanded sectional view which shows the contact part of a sliding contact protrusion and an output gear.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. The motor device according to the present embodiment is mounted on an automobile together with a power seat device, and is used as a drive source of the power seat device.

  An automobile 10 shown in FIG. 1 is a sedan type passenger car, and a power seat device 11 capable of electrically adjusting the position and height of the seat surface, the inclination of the seat back, etc. is provided in the driver's seat and the passenger seat. It is mounted.

  The power seat device 11 includes a seat cushion portion 12 and a seat back portion 13. In the seat cushion portion 12 and the seat back portion 13, a motor device 20 for seat position adjustment is incorporated.

  The motor device 20 incorporated in the seat cushion 12 moves the seat cushion 12 in the longitudinal direction or the vertical direction of the vehicle. The motor device 20 built in the seat back portion 13 reclines the seat back portion 13 and moves the lumbar support portion 13 a of the seat back portion 13 inward (vehicle rear) or outside (vehicle front).

  The plurality of motor devices 20 incorporated in the power seat device 11 are rotationally driven in forward and reverse directions by the operation of the operation switches by the driver or the passenger, and appropriately perform the above-described movement operation. Hereinafter, the structure of the motor device 20 will be described in detail.

  As shown in FIGS. 2 and 3, the motor device 20 includes a motor unit 30 and a gear unit 40. Further, a feed member 50 for supplying a drive current to the motor unit 30 is provided between the motor unit 30 and the gear unit 40. The motor unit 30 and the gear unit 40 are coupled to each other and coupled by three fastening screws SC (only two are shown in the figure), and between the coupled motor unit 30 and the gear unit 40 The feed member 50 is held.

  As shown in FIG. 2, the motor unit 30 includes a motor yoke 31 formed by forming a steel plate made of a magnetic material into a predetermined shape by pressing or the like. Specifically, a step-like bottom 31a is provided on one longitudinal side (right side in the figure) of the motor yoke 31 by press working, and a flange 31b is provided on the other longitudinal side (left side in the figure) by pressing. Is provided. The motor yoke 31 includes a pair of arc surface portions 31 c and a pair of flat portions 31 d (only one of which is shown in the drawing), and rotatably accommodates the rotating body RU. The pair of arc surface portions 31c and the pair of flat portions 31d are opposed to each other in the direction intersecting with the axial direction of the axial center C1 of the rotating body RU. The pair of arc surface portions 31c and the pair of flat portions 31d are alternately connected along the circumferential direction of the rotating body RU, whereby the cross-sectional shape of the motor yoke 31 is substantially oval.

  That is, in the motor yoke 31, the thickness dimension along the direction in which the pair of flat surface portions 31d opposes is thinner than the thickness dimension along the direction in which the pair of arc surface portions 31c opposes. As a result, the motor unit 30 becomes flat and it becomes easy to install the motor device 20 in a narrow space. The gear case 41 forming the gear portion 40 also has a flat shape following the flat shape of the motor yoke 31.

  A permanent magnet 32 having a substantially C-shaped cross-sectional shape is fixed to the inside of the arc surface portion 31 c of the motor yoke 31. Inside the pair of permanent magnets 32, an armature 34 having a coil (winding) 33 wound thereon is rotatably accommodated via a predetermined gap. Furthermore, an armature shaft (rotational shaft) 35 is disposed inside the armature 34. The armature shaft 35 passes through the axial center of the armature 34 and is fixed to the armature 34. The armature shaft 35 is provided to traverse both the motor unit 30 and the gear unit 40. One side (right side in the figure) of the armature shaft 35 in the axial direction is disposed in a bearing holding portion 31e further formed to project from the stepped bottom portion 31a, and is rotated by a first bearing B1 disposed in the bearing holding portion 31e. It is freely supported. On the other hand, the other axial side (left side in the drawing) of the armature shaft 35 is disposed in the gear case 41, and is rotatably supported by a second bearing B2 disposed in the gear case 41.

  A substantially cylindrical commutator 36 is fixed at a substantially central portion along the axial direction of the armature shaft 35 and at a position close to the armature 34. The end of the coil 33 wound around the armature 34 is electrically connected to the commutator 36.

  A pair of brushes 54 provided on the power supply member 50 is in sliding contact with the outer periphery of the commutator 36. The pair of brushes 54 are respectively pressed toward the commutator 36 with a predetermined pressure by the torsion type spring members. When a drive current is supplied from the on-vehicle controller (not shown) to the pair of brushes 54, the drive current is supplied to the commutator 36 to generate an electromagnetic force in the armature 34. Thus, the armature shaft 35 rotates at a predetermined number of rotations and rotational torque.

  A worm gear 37 is provided at an end of the armature shaft 35 entering the gear case 41. The worm gear 37 has a substantially cylindrical shape, and is integrally provided on the armature shaft 35 by rolling or the like. The worm gear 37 meshes with a worm wheel gear 42 rotatably accommodated in the gear case 41. Thus, the worm gear 37 rotates in the gear case 41 as the armature shaft 35 rotates, and the rotation is transmitted to the worm wheel gear 42.

  As shown in FIGS. 2 and 3, the gear case 41 is formed in a predetermined shape by a resin material such as plastic. The gear case 41 includes a plurality of gears and accommodates at least a speed reduction mechanism SD (FIG. 2) for decelerating the rotation of the motor unit 30. As shown in FIG. 3, in the gear case 41, a bottom 41a including a first bottom 41a1, a second bottom 41a2 and a step 41a3, and a side wall 41b vertically or substantially perpendicularly rising from the bottom 41a. A gear housing portion 60 is formed with an opening.

  The step 41a3 is interposed between the first bottom 41a1 and the second bottom 41a2, and the first bottom 41a1 is connected to the second bottom 41a2 through the step 41a3, and the second bottom 41a2 is formed by the step 41a3. It is continuous with the first bottom 41a1.

  The worm wheel gear (first gear) 42 and the output gear (final gear) 43 are incorporated into the gear housing 60 via the opening 41 d. The worm wheel gear 42 incorporated in the gear housing 60 is mounted on the second bottom 41a2, and the output gear 43 is mounted on the first bottom 41a1. Further, the worm wheel gear 42 and the output gear 43 incorporated in the gear housing 60 are surrounded by the side wall 41 b of the gear housing 60. The output gear 43 corresponds to the final gear of the reduction gear mechanism SD, and the worm wheel gear 42 corresponds to the gear immediately before the final gear of the reduction gear SD.

  As shown in FIG. 3, the opening 41 d of the gear housing portion 60 is formed in a substantially gourd shape following the shapes of the worm wheel gear (small diameter gear) 42 and the output gear (large diameter gear) 43. The opening 41 d is closed by a gear cover 44 formed in a substantially gourd shape by a resin material such as plastic. Here, as shown in FIG. 2, three engaging projections 41 e are provided on the outside of the side wall portion 41 b of the portion where the output gear 43 of the gear housing portion 60 (FIG. 3) is incorporated. Three engagement claws 44a engaged with the engagement projections 41e are provided. Further, as shown in FIG. 3, three female screw parts 41 f are provided in the vicinity of the opening 41 d of the side wall part 41 b of the part where the worm wheel gear 42 is incorporated in the gear housing 60. Three screw insertion holes 44b are provided to face the portion 41f.

  That is, the gear cover 44 is fixed to the gear case 41 by three engagement protrusions 41 e and three engagement claws 44 a in addition to the fixation with the three fixing screws S. Thus, when the motor device 20 is assembled, temporary fixing of the gear cover 44 to the gear case 41 can be reliably performed by the engagement protrusions 41 e and the engagement claws 44 a provided three by three, thereby assembling the motor device 20. Workability is improved. Further, even when a large load is applied when the motor device 20 is used, the gear cover 44 is firmly fixed to the gear case 41 by the three fixing screws S. Accordingly, rattling of the gear cover 44 with respect to the gear case 41 is suppressed, and the generation of abnormal noise from the motor device 20 is suppressed.

  Furthermore, as shown in FIG. 3, an engagement convex portion 41 h is formed around the female screw portion 41 f closest to the motor portion 30 among the three female screw portions 41 f. On the other hand, an engagement recess 44d is formed around the screw insertion hole 44b communicating with the female screw portion 41f. As shown in FIG. 4, when the gear cover 44 is put on the gear case 41, the engagement convex portion 41 h provided on the gear case 41 is fitted inside the engagement concave portion 44 d provided on the gear cover 44. As shown in FIG. 2 and FIG. 3, the engaging convex portion 41 h and the engaging concave portion 44 d include an axial center (rotational axis) C 3 of the worm wheel gear 42 and an axial center (rotational axis) C 4 of the output gear 43. It is arranged on the connecting straight line X. More specifically, the opposing set of engaging protrusion outer surface and engaging recess inner surface are located on one side of the straight line X, and the other pair of opposing engaging protrusion outer surface and engaging recess inner surface are straight It is located on the other side of X. Therefore, the elastic deformation (twisting) of the gear cover 44 is effectively prevented even when a large torque is applied to the gear cover 44 by the engagement of the engagement convex portion 41 h and the engagement concave portion 44 d shown in FIG. 4. The rattling of the gear cover 44 with respect to the gear case 41 and the generation of abnormal noise due to the collision of the gear cover 44 and the gear case 41 are suppressed. The gear cover 44 is mirror-symmetrical with the straight line X shown in FIG. 2 as the axis of symmetry. Generally as a motor device mounted in a car, for example, as typified by a motor device for driving a power window, a pair of left and right pair is often used. In that case, the output shaft 43a to the gear case 41 is Are designed to differ by 180 degrees (so-called p-type q-type motor device). Even in the gear case 41 in the present embodiment, two types of gear cases 41 are set to correspond to such purpose of use. However, as described above, the gear cover 44 has a straight line X along the axis of symmetry. Because of the mirror-symmetrical shape, the gear cover 44 can be shared by making the shape of the opening 41 d of the gear case 41 the same, even when the specifications of the gear case 41 are different. It is possible to cope with the layout change of the motor device 20 without increasing the number of parts.

  Refer to FIG. 3 again. The worm wheel gear 42 constituting the reduction mechanism SD (FIG. 2) is formed substantially in a disk shape from a resin material such as plastic, and has a large diameter gear portion 42a and a small diameter gear portion 42b smaller in diameter than the large diameter gear portion 42a. Is equipped. The worm wheel gear 42 is rotatably supported by a support pin P, one end of which is fixed to the second bottom 41a 2 of the gear housing 60. That is, the axial center of the support pin P is the axial center (rotational axis) C3 of the worm wheel gear 42. The large diameter gear portion 42 a of the worm wheel gear 42 is meshed with a worm gear 37 provided on the armature shaft 35.

  The other end side of the support pin P is fixed to an engaging portion 44 e provided on the gear cover 44 (not shown in detail). Therefore, in order to prevent gear cover 44 from rattling gear case 41 due to a relatively large load applied to support pin P, three fixing screws S are arranged at intervals of approximately 120 degrees so as to surround support pin P. It is done. Note that one of the three fixing screws S is disposed on the straight line X as described above (see FIG. 2).

  An output gear 43, which constitutes the reduction mechanism SD (FIG. 2) together with the worm wheel gear 42, has a diameter larger than that of the worm wheel gear 42, and is engaged with the small diameter gear portion 42b of the worm wheel gear 42. A substantially cylindrical output shaft 43a is integrally provided on a shaft center (rotational shaft) C4 of the output gear 43. A serration fitting portion 43b formed in an uneven shape is formed on the inner side in the radial direction of the output shaft 43a. A power transmission mechanism (not shown) such as a screw for reclining the seat back portion 13 (FIG. 1) is fitted to the serration fitting portion 43b so as to be integrally rotatable.

  Both axial direction sides of the output shaft 43 a are respectively projected from both side surfaces along the axial direction of the output gear 43 at a predetermined height. And both sides in the axial direction of the output shaft 43a are a case-side boss portion (support hole) 41g integrally provided on the first bottom portion 41a1 of the gear housing portion 60 and a cover-side boss portion 44c integrally provided on the gear cover 44. And are each rotatably supported.

  As shown in FIG. 3, in the first bottom portion 41 a 1 of the gear housing portion 60, in the portion facing the side surface of the output gear 43, the contact area with the output gear 43 is reduced to slide the output gear 43. A plurality of sliding projections 70 are provided to reduce the resistance. Each sliding contact projection 70 is formed one step higher than the first bottom portion 41 a 1, and on the end face of each sliding contact projection 70, a recess (grease reservoir) 71 for holding grease (not shown) is formed. It is done.

  The plurality of sliding projections 70 are arranged on the circumference of a circle centered on the axial center (rotational axis) C3 of the output gear 43, and are arranged at predetermined intervals in a region avoiding the step portion 41a3. In the present embodiment, six sliding projections 70 are arranged at equal intervals on the circumference. Among the six sliding projections 70, the sliding projections 70 at both ends in the arrangement direction have a shorter length in the arrangement direction than the other sliding projections 70. Further, two grease reservoirs 71 are formed on the end faces of the four sliding contact projections 70 whose length in the arrangement direction is relatively long, and two sliding contacts of both ends in which the length in the arrangement direction is relatively short are formed. One grease reservoir 71 is formed on the end face of the projection 70.

  A plurality of sliding contact projections 70 are adjacent to each other via a gap 72, and between adjacent sliding contact projections 70, a gap that allows communication between a region inside the sliding contact projection 70 of the bottom portion 41a and a region outside the sliding contact projection 70 ( Aisle 72 is present.

  Here, as shown in FIG. 3, the output gear 43 is provided with an annular sliding ring portion 43 c. Specifically, the output gear 43 is formed with a plurality of connecting portions 43d radially extending around the output shaft 43a, and a sliding contact portion 43c concentric with the output shaft 43a is formed at the tip of the connecting portions 43d. An outer peripheral gear portion 43e which is formed and is engaged with the small diameter gear portion 42b of the worm wheel gear 42 is formed around the sliding contact ring portion 43c. That is, the output gear 43, which is the gear of the final stage of the reduction gear mechanism SD (FIG. 2), includes the output shaft 43a, the sliding contact portion 43c formed around the output shaft 43a, and the periphery of the sliding contact ring 43c. The output shaft 43a, the sliding ring 43c, and the outer peripheral gear 43e are concentric. Furthermore, the sliding contact ring portion 43c of the output gear 43 is located on the same circumference as the circumference where the sliding contact projection 70 is disposed.

  As shown in FIG. 5, while the end surface 70a of the sliding contact protrusion 70 provided on the inner surface of the first bottom portion 41a1 is a flat surface, the end surface 43f of the sliding contact ring 43c slidingly contacts the end surface 70a of the sliding contact protrusion 70. Is a circular arc surface. The apex of the end face (circular arc surface) 43f of the sliding contact ring portion 43c is located on the same circumference as the circumference where the sliding contact projection 70 is disposed. As a result, the contact area between the sliding contact protrusion 70 (bottom 41a of the gear housing 60) and the sliding ring 43c (output gear 43) is further reduced, and the sliding resistance of the output gear 43 is further reduced.

  As described above, in the motor device 20 according to the present embodiment, the plurality of sliding contact projections 70 are provided in a projecting manner on the first bottom portion 41 a 1 of the gear housing 60 and are accommodated in the gear housing 60 by the sliding projections 70. An output gear 43 is rotatably supported. Therefore, the sliding resistance between the gear accommodating portion 60 and the output gear 43 accommodated in the gear accommodating portion 60 is reduced, and the generation of noise from the abrasion of the sliding portion and the sliding portion is prevented or suppressed. Improved durability and reliability of 20. Furthermore, concave portions (grease reservoirs) 71 for retaining grease are provided in the respective sliding contact projections 70, and as the output gear 43 rotates, the grease circulates between the grease reservoirs 71. Therefore, the grease applied to the sliding portion is not broken in a short time, and smooth sliding is maintained for a long time. Further, since the sliding contact projection 70 is formed in a region avoiding the step portion 41a3 between the first bottom portion 41a1 and the second bottom portion 41a2, even if the motor device 20 has a step in the bottom portion 41a of the gear case 41. The sliding contact projection 70 can be provided to hold the grease effectively regardless of the shape of the bottom 41a.

  The present invention is not limited to the above embodiment, and various modifications can be made without departing from the scope of the invention. For example, the motor unit 30 can be replaced by a brushless motor. Further, the motor unit 30 is not limited to the electric motor, and may be replaced by a hydraulic motor or a pneumatic motor.

  Further, the present invention is applicable not only to the motor device for adjusting the seat position but also to a motor device used as a drive source of other devices such as a power window device and a wiper device.

DESCRIPTION OF SYMBOLS 10 car 11 power seat device 12 seat cushion portion 13 seat back portion 13a lumbar support portion 20 motor device 30 motor portion 31 motor yoke 31a step-like bottom portion 31b flange portion 31c arc surface portion 31d flat portion 31e bearing holding portion 32 permanent magnet 33 coil 34 Armature 35 Armature shaft 36 Commutator 37 Worm gear 40 Gear portion 41 Gear case 41a Bottom portion 41a1 First bottom portion 41a2 Second bottom portion 41a3 Stepped portion 41b Side wall portion 41d Opening 41e Engaging projection 41f Female thread 41h Engaging projection 42 Worm wheel gear 42a Large Diameter gear portion 42b Small diameter gear portion 43 Output gear 43a Output shaft 43b Serration fitting portion 43c Sliding contact portion 43d Coupling portion 43e Outer peripheral gear portion 43f (at sliding contact portion) end face 44 Gear cover 44a Engaging claw 44b Screw insertion hole 44c Cover side boss 44d Engaging recess 44e Engaging part 50 Feeding member 54 Brush 60 Gear housing 70 Sliding contact projection 70a (Sliding projection) end face 72 Clearance B1 First bearing B2 Second Bearings C1, C2, C3 Axis (rotational axis)
P Support pin RU Rotor S Fixing screw SC Fastening screw SD Reduction mechanism X Straight

Claims (7)

A motor device comprising: a motor; a reduction mechanism for reducing the speed of rotation of the motor; and a gear case for accommodating the reduction mechanism.
A gear accommodating portion provided in the gear case and rotatably accommodating a gear constituting the reduction gear mechanism;
A plurality of sliding contact projections provided on an inner surface of the gear housing and in sliding contact with the gear;
The plurality of sliding projections are disposed at predetermined intervals on the circumference of a circle centered on the rotation axis of the gear .
The gear has an annular sliding contact ring portion, an outer peripheral gear portion provided around the sliding contact ring portion, and a radially outer side than the sliding contact ring portion and an inner radial direction than the outer peripheral gear portion And a recess provided in the
The sliding projection always slides on the sliding ring portion,
Motor device. The motor device according to claim 1,
The gear housing includes a bottom facing the side of the gear, and a side wall rising from the bottom and surrounding the gear.
The sliding projection is provided on the inner surface of the bottom portion.
Motor device. In the motor device according to claim 1 or 2,
A recess for holding grease is formed on the end face of the sliding contact protrusion,
Motor device. The motor device according to any one of claims 1 to 3.
The plurality of sliding projections are arranged at equal intervals,
Motor device. In the motor device according to claim 4 ,
The end face of the sliding contact portion slidingly contacting the sliding contact protrusion is a circular arc surface,
Motor device. In the motor device according to any one of claims 1 to 5 ,
The speed reduction mechanism includes a plurality of gears.
The gear in sliding contact with the sliding projection is a gear of the final stage of the reduction gear mechanism,
Motor device. In the motor device according to claim 6 ,
The gear accommodating portion is connected to a first bottom portion on which the gear of the final stage is mounted, and a second bottom portion on which the gear immediately before the gear of the final stage is mounted on the first bottom portion via a step portion. And
The sliding projection is provided on an inner surface of the first bottom portion, in a region avoiding the step portion.
Motor device.

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