JP2020178462A - Motor device - Google Patents

Abstract

To reduce the assembling failure of a brush in a motor device.SOLUTION: A motor device has a brush holder 60 holding a brush 28, a brush holder stay 64 provided with the brush holder 60, and a spring 29 pressing a back surface portion 28a of the brush 28 toward a commutator 27. An end portion 28b on the brush holder stay side of the back surface portion 28a is at a position separated from an armature shaft 26 than an end portion 28c on an armature core side of the back surface portion 28a. The brush holder 60 is equipped with a guiding surface 61c guiding a free end portion 29a of the spring 29 to the back surface portion 28a. The end portion 61a on the brush holder stay side of the guiding surface 61c is a position separated from the armature shaft 26 than an end portion 61b on the armature core side of the guiding surface 61c. An inclination angle with respect to the armature shaft 26 of the guiding surface 61c is larger than an inclination angle with respect to the armature shaft 26 of the back surface portion 28a.SELECTED DRAWING: Figure 6

Description

The present invention relates to a motor device in which a brush is brought into contact with a commutator to supply a current from the brush to a coil wound around a rotor.

As a drive source for a power window device or the like mounted on a vehicle such as an automobile, a motor device having a deceleration mechanism capable of obtaining a large output while being small is used. Then, by operating the switch provided in the vehicle interior, the motor device is rotated forward or reverse, and the window glass is moved up and down. For such a motor device, for example, the technique described in Patent Document 1 is used.

Patent Document 1 discloses a motor device including a brush pressed against a commutator, a brush holder for holding the brush, and a spring for urging the brush. The entire surface (back surface) of the rear end portion of the brush provided in this motor device is inclined at an angle to form a tapered portion, and the spring abuts on the rear end portion of the brush to direct the brush toward the commutator. Bounce.

Japanese Unexamined Patent Publication No. 8-214507

However, in the motor device shown in Patent Document 1, when the free end of the spring is set at the rear end of the brush in assembling the brush, the free end of the spring is set at the corner of the rear end of the brush. There was a problem that the part was caught and an assembly failure occurred.

An object of the present invention is to provide a motor device having improved assembling property.

One aspect of the present invention includes a rotating shaft, an armature core attached to the rotating shaft and around which a coil is wound, a commutator provided on the commutator, and a brush pressed against the commutator. A brush holder that holds the brush, a brush holder stay that is provided with the brush holder on the side opposite to the armature core side with respect to the brush, and a back portion of the brush. Has a spring having a free end and a spring support provided on the brush holder stay to support the spring, the back surface of the armature core of the armature core. In the radial direction, the end portion of the back surface portion on the brush holder stay side is inclined with respect to the rotation axis so as to be a position away from the rotation axis from the end portion of the back surface portion on the armature core side. The brush holder includes a guide surface that guides the free end portion of the spring to the back surface portion, and the guide surface is such that the end portion of the guide surface on the brush holder stay side in the radial direction is the guide surface. The tilt angle of the guide surface with respect to the rotation axis is such that the guide surface is inclined with respect to the rotation axis so as to be located away from the rotation axis from the end portion on the armature core side. Greater than the angle.

In the motor device, it is possible to reduce brush assembly defects.

It is a top view which shows the motor device of embodiment of this invention. It is a side view which shows the shape of the brush attached to the motor device of FIG. It is a partial side view which shows the pressing state to the brush by the spring in the motor device using the brush shown in FIG. It is a schematic diagram which shows the direction of the vector of the load by the pressing of a spring in the motor device shown in FIG. It is a partial perspective view which shows the moving state of the free end portion of a spring in the motor device shown in FIG. 1 to a brush holder. It is a schematic diagram which shows the movement start in the moving state of the free end portion of the spring shown in FIG. It is a schematic diagram which shows the end of movement in the moving state of the free end portion of the spring shown in FIG. It is a side view which shows an example of the inclination angle of the back part of the brush and the guide part of a brush holder in the motor device shown in FIG. It is a side view which shows the shape of the brush of the modification of embodiment of this invention. It is a side view which shows the shape of the brush in the motor device of the comparative example. It is a partial side view which shows the pressing state to the brush by the spring in the motor device of the comparative example. It is a side view which shows the assembly failure of the brush in the motor device of the comparative example.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Embodiment)
The motor device 10 shown in FIG. 1 is used as a drive source for a power window device mounted on a vehicle such as an automobile, and drives a wind regulator that raises and lowers a window glass. The motor device 10 is a small motor with a reduction mechanism capable of producing a large output, and is installed in a narrow space inside a vehicle door. The motor device 10 includes a motor unit 20 and a gear unit 40, and the motor unit 20 and the gear unit 40 are connected to each other by a plurality of fastening screws 11 to form a unit.

The motor unit 20 includes a motor case 21 formed in a bottomed tubular shape by pressing a steel plate made of a magnetic material or the like. The motor case 21 includes a pair of flat wall portions 21a facing each other and a pair of arcuate wall portions 21b facing each other, and the cross-sectional shape thereof is formed in a substantially oval shape. That is, the thickness dimension of the motor case 21 along the direction in which the flat wall portions 21a face each other (depth direction in FIG. 1) is reduced, whereby the motor portion 20 has a flat shape and the motor device 10 has a narrow space inside the door. It can be placed in. Here, the gear case 41 also has a flat shape following the flat shape of the motor case 21. In addition, in FIG. 1, only the flat wall portion 21a on the front side in the figure is shown.

Inside each arc-shaped wall portion 21b of the motor case 21, a plurality of magnets 22 having a substantially arc-shaped cross section are fixed. Inside each magnet 22, an armature 24 including an armature core 25 around which a coil 23 is wound is rotatably provided through a predetermined gap. A brush holder 60 is attached to the opening side of the motor case 21 (left side in FIG. 1), and the opening side of the motor case 21 is closed by the brush holder 60.

An armature shaft (rotation shaft) 26 penetrates and is fixed to the rotation center of the armature core 25 included in the armature 24. That is, the armature 24 has an armature shaft 26 which is a rotation shaft, and an armature core 25 which is attached to the armature shaft 26 and has a coil 23 wound around it. The armature shaft 26 is provided so as to cross both the motor portion 20 and the gear portion 40, and one side of the armature shaft 26 in the axial direction (right side in FIG. 1) is arranged in the motor case 21 and is the shaft of the armature shaft 26. The other side in the direction (left side in FIG. 1) is arranged in the gear case 41. That is, the armature shaft 26 is rotatably housed inside the motor case 21 and the gear case 41.

A commutator 27 formed in a substantially cylindrical shape is provided at a substantially intermediate portion along the axial direction of the armature shaft 26 and a portion close to the armature core 25. The commutator 27 rotates integrally with the armature shaft 26, and the end of the coil 23 wound around the armature core 25 is electrically connected to the commitator 27.

A plurality of brushes 28 held by the brush holder 60 are slidably contacted on the outer circumference of the commutator 27, and each brush 28 has a spring whose back surface (rear end) 28a shown in FIG. 3 of each brush 28 is coiled. Each of the free end portions 29a of 29 is pressed against the commutator 27 with a predetermined pressure. As a result, by supplying a drive current to the armature core 25 from an in-vehicle controller (not shown) via each brush 28, a rotational force (electromagnetic force) is generated in the armature core 25, and the armature shaft 26 eventually rotates in a predetermined rotation direction. Is rotated to.

As shown in FIG. 5, the spring 29 is attached to the spring support portion 63 provided on the brush holder stay 64.

Further, an annular sensor magnet 30 is fixed at a substantially intermediate portion along the axial direction of the armature shaft 26 and on the side of the commutator 27 opposite to the armature core 25 side. The sensor magnet 30 has a plurality of polarities along the rotation direction of the armature shaft 26. The sensor magnet 30 is integrally rotated with the armature shaft 26, so that the state of the magnetic flux line with respect to the rotation sensor 55 arranged on the outer side in the radial direction of the sensor magnet 30 changes with the rotation of the armature shaft 26. ing.

A worm 31 is provided on the other side of the armature shaft 26 in the axial direction from the sensor magnet 30. The worm 31 is formed in a substantially tubular shape and is fixed to the armature shaft 26 by press fitting or the like. The worm 31 is meshed with the tooth portions 43a (not shown in detail) of the worm wheel 43 rotatably housed in the gear case 41. As a result, the worm 31 is rotated by the rotation of the armature shaft 26 in the gear case 41, and the rotation is transmitted to the worm wheel 43. Here, the worm 31 and the worm wheel 43 form a reduction mechanism SD.

The bottom side (right side of FIG. 1) of the motor case 21 is formed in a stepped shape, and a small diameter portion 21c having a diameter smaller than that of the main body portion of the motor case 21 is provided at the portion. A first bearing member 32 is provided in the small diameter portion 21c, and the first bearing member 32 rotatably supports one side of the armature shaft 26 in the axial direction in the motor case 21.

The gear portion 40 includes a gear case 41 and a connector member 50. The opening portion (front side in FIG. 1) of the gear case 41 is closed by a gear cover 42 formed in a substantially disk shape. Further, the gear case 41 is formed into a predetermined shape by injection molding a resin material such as plastic, and is connected to the opening side of the motor case 21 via each fastening screw 11. That is, the gear case 41 and the motor case 21 both form an outer shell of the motor device 10.

In the gear case 41, a worm 31 fixed to the armature shaft 26 and a worm wheel 43 having a tooth portion 43a that meshes with the worm 31 on the outer peripheral portion are housed rotatably. Here, the worm 31 is formed in a spiral shape, and the tooth portion 43a is gently inclined in the axial direction of the worm wheel 43. This enables smooth power transmission from the worm 31 to the worm wheel 43.

An output member 43b is provided at the center of rotation of the worm wheel 43, and the output member 43b is connected to the wind regulator so as to be able to transmit power. That is, the rotation of the armature shaft 26 is decelerated by the reduction mechanism SD to increase the torque, and the increased torque rotational force is output from the output member 43b to the wind regulator.

A second bearing member 44 is provided in the gear case 41 at a portion of the armature shaft 26 corresponding to the other side in the axial direction. The second bearing member 44 rotatably supports the other side of the armature shaft 26 in the axial direction in the gear case 41.

A connector member assembly hole 41a is provided on a side surface portion (upper side of FIG. 1) of the gear case 41. The connector member 50 is inserted and fixed in the connector member assembly hole 41a. The extending direction of the connector member assembly hole 41a, that is, the insertion direction of the connector member 50 is a direction orthogonal to both the extending direction of the armature shaft 26 and the extending direction of the output member 43b.

Here, an O-ring (not shown) as a seal member is mounted between the connector member assembly hole 41a and the connector member 50, whereby rainwater or the like enters the connector member assembly hole 41a. Is blocked. Further, the connector member 50 is firmly fixed to the gear case 41 by a plurality of fixing screws (not shown) without rattling. The connector member 50 is formed into a substantially L shape by injection molding a resin material such as plastic. The connector member 50 includes an assembly portion (not shown) to be assembled to the gear case 41, and a connector connection portion 52 to which the external connector CN is connected. The connector member 50 is electrically connected to the brush holder 60 and supplies a drive current from the external connector CN to the brush holder 60.

The gear case 41 is provided with three fixing portions 41d. These fixing portions 41d are arranged around the gear case 41 at predetermined intervals (approximately 120 ° intervals) so as to surround the output member 43b. Then, fixing bolts (not shown) for fixing the motor device 10 in the door of the vehicle are attached to each fixing portion 41d. In this way, by providing the fixing portions 41d at predetermined intervals so as to surround the output member 43b, the motor device 10 is supported in a well-balanced manner in the narrow door. Therefore, even if a high load is applied to the motor device 10, it is possible to effectively prevent the motor device 10 from rattling in the door.

Next, the brush assembled to the motor device 10 of the present embodiment will be described.

First, the brush 78 of the comparative example that the present inventor has compared and examined with reference to FIGS. 10 to 12 will be described.

In the assembly of the brush 78 of the comparative example shown in FIG. 10, the free end portion 29a of the spring 29 is the surface opposite to the back surface portion of the brush 78 (as shown in FIG. 11 and rectified by contacting with the commutator 27). (Also referred to as the rear end portion) 78a, as shown in FIG. 12, the free end portion 29a of the spring 29 is caught by the corner portion of the upper end of the back surface portion 78a of the brush 78. As a result, there is a problem that the brush 78 is poorly assembled.

Further, the back surface portion 78a of the brush 78 pressed by the free end portion 29a of the spring 29 is a surface that is parallel to the armature shaft (rotation shaft) 26 shown in FIG. 11, and is formed on the armature shaft 26. On the other hand, the surface is not tilted. Therefore, when the back surface 78a of the brush 78 is pressed by the free end 29a of the spring 29, the load P applied to the back surface 78a is the brush holder stay 64 provided with the brush holder (see FIG. 5) 60. It is given in the horizontal direction with respect to.

As a result, a clearance Q is formed between the brush 78 and the brush holder stay 64, and when the armature core 25 rotates, the brush 78 tends to run wild.

Therefore, in the motor device 10 of the present embodiment, as shown in FIGS. 2 and 3, the back surface portion (rear end portion) 28a of the brush 28 pressed by the free end portion 29a of the spring 29 is attached to the armature shaft 26. On the other hand, it is inclined. That is, the back surface portion 28a of the brush 28 has a tapered surface inclined with respect to the armature shaft 26.

Specifically, in the radial direction K of the armature core 25, the end 28b of the back surface 28a of the brush 28 on the brush holder stay 64 side is located at a position away from the armature shaft 26 from the end 28c of the back surface 28a on the armature 24 side. 28a is a tapered surface that is inclined with respect to the armature shaft 26. That is, the back surface portion 28a and the armature shaft 26 are not parallel to each other. The pigtail 28d, which is a conductive wire, is electrically connected to the first surface 28e connected to the end portion 28c of the back surface portion 28a of the brush 28. The pigtail 28d is connected near the end of the first surface 28e. Here, in the side view of the brush 28, the length of the armature core 25 of the first surface 28e to which the pigtail 28d is connected along the radial direction K and the armature of the second surface 28f opposite to the first surface 28e. In terms of the length of the core 25 in the radial direction K, the second surface 28f has a longer length and protrudes in a direction away from the armature axis 26. In other words, the side view shape of the brush 28 is substantially trapezoidal.

Therefore, when the back surface portion 28a of the brush 28 is pressed by the free end portion 29a of the spring 29, the back surface portion 28a has a tapered surface inclined with respect to the armature shaft 26, as shown in FIG. A load is also applied to the brush holder stay 64 side like the load P1.

Specifically, as shown in FIG. 4, the load applied to the back surface portion 28a of the brush 28 by the free end portion 29a of the spring 29 is decomposed into P2 and P3, and further applied to the commutator 27 by the brush 2. The load is decomposed into P4 and P5.

As a result, the load (P3) pressed against the brush holder stay 64 is also applied to the brush 28, so that the brush 28 also comes into contact with the brush holder stay 64 as shown in FIG. That is, the clearance Q as shown in FIG. 11 is not formed between the brush 28 and the brush holder stay 64, and therefore, the brush runaway caused by the rotation of the armature 24 can be suppressed.

Further, as shown in FIG. 5, the brush holder 60 includes a guide portion 61 having a guide surface 61c that guides the free end portion 29a of the spring 29 to the back surface portion 28a of the brush 28. Further, as shown in FIGS. 6 and 7, the end portion 61a of the guide surface 61c of the guide portion 61 on the brush holder stay 64 side is a guide surface in the direction along the radial direction K of the armature core 25 shown in FIG. It is arranged at a position away from the armature shaft 26 from the end portion 61b on the armature core 25 side of 61c. As a result, the guide surface 61c is also a tapered surface inclined with respect to the armature shaft 26. That is, the guide surface 61c and the armature shaft 26 are not parallel.

In the motor device 10 of the present embodiment, the inclination angle α1 (see FIG. 8) of the guide surface 61c of the guide portion 61 of the brush holder 60 with respect to the armature shaft 26 is such that the back surface portion 28a of the brush 28 is tilted with respect to the armature shaft 26. The angle is larger than α2 (see FIG. 8) (α1> α2).

In the structure shown in FIG. 8, a predetermined line parallel to the armature axis 26 is represented as a reference line S, the inclination angle of the guide surface 61c with respect to the reference line S is α1, and the inclination angle of the back surface portion 28a with respect to the reference line S is set. It is set to α2. Then, α1> α2. As an example, α1 = 27 ° and α2 = 12 °.

Further, to explain the structure shown in FIG. 8 in another expression, the angle of the dent angle formed by the guide surface 61c and the reference line S is α1, and the angle of the dent angle formed by the back surface portion 28a and the reference line S is α2. It has become. At that time, α1> α2. In the present embodiment, the angle of the angle is the angle on the acute angle side of the angle of the angle formed by the guide surface 61c and the armature shaft 26, and similarly, the angle formed by the back surface 28a and the armature shaft 26. It is the angle on the acute angle side of the angles of.

As described above, the inclination angle α1 of the guide surface 61c with respect to the armature shaft 26 is formed to be larger than the inclination angle α2 of the back surface 28a with respect to the armature shaft 26, so that the guide surface 61c is inclined with respect to the armature shaft 26. The angle can be increased.

In other words, comparing the structure in which the guide surface 61c is not formed in the brush holder 60 and the structure in which the guide surface 61c shown in FIG. 5 is formed and the inclination angle of the guide surface 61c is large, the inclination is compared. By adopting a structure having a guide surface 61c formed with a large angle, the free end portion 29a of the spring 29 can be smoothly guided to the recess 62 of the brush holder 60 (R portion in FIG. 5).

That is, in the motor device 10 of the present embodiment, the shape of the side view of the brush 28 is substantially trapezoidal, the back surface 28a of the brush 28 is a tapered surface, and the inclination angle of the guide surface 61c of the brush holder 60. Is formed at an angle larger than the inclination angle of the back surface portion 28a of the brush 28. As a result, as shown in FIG. 6, the free end portion 29a of the spring 29 is guided to the recess 62 of the brush holder 60 (operations of the arrows R1 and R2 shown in FIG. 6), and the back surface portion 28a of the brush 28 is pressed. The free end 29a of the spring 29 can be smoothly guided along the shapes of the guide surface 61c and the recess 62 of the brush holder 60.

As a result, the free end 29a of the spring 29 is less likely to be caught at the corners of the upper end of the back surface 28a of the brush 28, and poor assembly of the brush 28 can be reduced. Thereby, the assembling property of the motor device 10 can be improved.

Further, as shown in FIG. 6, the end portion 61a of the guide surface 61c in the guide portion 61 of the brush holder 60 is the first surface 28e of the brush 28 (see FIG. 3) in the radial direction K (see FIG. 3) of the armature core 25. (See) protruding from the end 28c in a direction away from the armature shaft 26.

As a result, when guiding the free end 29a of the spring 29 to the back surface 28a of the brush 28 along the guide surface 61c of the brush holder 60, the upper end of the back surface 28a of the brush 28 of the free end 29a of the spring 29 It is possible to further reduce the possibility of catching at the corners and the like, and further reduce the assembly failure of the brush 28.

(Modification example)
The modified example shown in FIG. 9 shows a modified example of the shape of the brush 28, and the difference from the shape of the brush 28 shown in FIG. 2 is that the back surface portion 28a of the brush 28 is on the armature core 25 (see FIG. 3) side. The shape of the end portion 28c (T portion in FIG. 9) is a curved portion 28g.

That is, the brush 28 has a tapered surface whose back surface 28a is inclined with respect to the armature shaft 26 like the brush 28 shown in FIG. 2, and the end 28c of the back surface 28a on the armature core 25 side (FIG. 9). The T portion) is a curved portion (28 g). That is, the corner portion of the brush 28 where the first surface 28e to which the pigtail 28d is connected and the back surface portion 28a intersect has a curved shape (curved portion 28g).

Since the corners where the back surface 28a and the first surface 28e intersect are formed in a curved shape, the back surface 28a of the brush 28 is guided when the free end 29a of the spring 29 is guided to the back surface 28a of the brush 28. It is possible to further reduce the occurrence of catching of the free end portion 29a at the corner portion of the upper end of the. As a result, the assembly failure of the brush 28 can be further reduced, and the assembling property of the motor device 10 can be further improved.

Since the other effects obtained by the brush 28 of this modification are the same as the effects of the brush 28 of the embodiment shown in FIG. 2, the duplicate description will be omitted.

It goes without saying that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist thereof. For example, in the above embodiment, the case where the motor device 10 is used as a drive source for a power window device mounted on a vehicle such as an automobile has been described. However, the motor device 10 is, for example, driving a sunroof device. It may be the one used as the source.

10 Motor device 11 Fastening screw 20 Motor part 21 Motor case 21a Flat wall part 21b Arc-shaped wall part 21c Small diameter part 22 Magnet 23 Coil 24 Armature 25 Armature core 26 Armature shaft (rotating shaft)
27 Commutator
28 Brush 28a Back 28b End 28c End 28d Pigtail 28e 1st surface 28f 2nd surface 28g Curved part 29 Spring 29a Free end 30 Sensor magnet 31 Warm 32 1st bearing member 40 Gear part 41 Gear case 41a Connector member assembly Hole 41d Fixing part 42 Gear cover 43 Worm wheel 43a Tooth part 43b Output member 44 Second bearing member 50 Connector member 52 Connector connection part 55 Rotation sensor 60 Brush holder 61 Guide part 61a End part 61b End part 61c Guide surface 62 Recession 63 Spring support Part 64 Brush holder stay 78 Brush 78a Back part CN external connector SD deceleration mechanism

Claims (1)

It is a motor device including a rotating shaft, an armature core attached to the rotating shaft and around which a coil is wound, a commutator provided on the rotating shaft, and a brush pressed against the commutator. hand,
A brush holder that holds the brush and
The brush holder stay provided on the side opposite to the armature core side with respect to the brush, and the brush holder stay.
A spring with a free end that presses the back of the brush toward the commutator,
A spring support portion provided on the brush holder stay and supporting the spring,
Have,
The back surface portion is such that the end portion of the back surface portion on the brush holder stay side is located away from the rotation axis of the back surface portion on the armature core side in the radial direction of the armature core. Tilt with respect to the axis of rotation,
The brush holder includes a guide surface that guides the free end of the spring to the back surface.
The guide surface has a rotation shaft such that the end portion of the guide surface on the brush holder stay side is located away from the rotation shaft of the guide surface on the armature core side in the radial direction. Tilt against
A motor device in which the inclination angle of the guide surface with respect to the rotation axis is larger than the inclination angle of the back surface portion with respect to the rotation axis.

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