JP3538047B2 - Brush holding structure, brush holding housing and motor in motor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brush holding structure for a motor, a brush holding housing provided with the brush holding structure, and a motor provided with the brush holding housing.

[0002]

2. Description of the Related Art Conventionally, as a brush holding structure in a small DC motor, for example, as disclosed in Japanese Utility Model Laid-Open No. 61-43768 and Japanese Utility Model Laid-Open No. 6-52370, a base end is separated from an output shaft. There has been proposed a brush holding structure using a leaf spring-like holding member fixed to the outer peripheral side and extending the tip end side to which the brush is fixed to the commutator side.

[0003] A brush holding structure for holding a brush with a leaf spring-like member is disclosed in, for example, Japanese Utility Model Laid-Open No. 4-111263, in which a brush provided with a guide portion provided in a motor casing has a diameter relative to a rotating shaft. Unlike the brush holding structure in which the brush is movably held in the direction and the brush is biased toward the commutator by a spring member provided outside the guide portion, the structure can be simplified.

[0004]

By the way, in order to suppress the loss of the motor caused by the brush, that is, the brush resistance loss and the brush friction loss, the brush is applied with an urging force within an appropriate range regardless of the wear amount. It must be pressed against the commutator. That is, it is necessary to minimize the change in the urging force with respect to the displacement of the leaf spring-like member due to the wear of the brush. For this purpose, it is necessary to make the length of the displaced portion of the spring member as long as possible so that the portion in contact with the brush has a small amount of change in the urging force applied to the brush with respect to the amount of displacement.

However, in the brush holding structure disclosed in Japanese Utility Model Laid-Open No. 61-43768 and Japanese Utility Model Laid-Open No. 6-52370, the length of the displaced portion of the leaf spring-like member is not sufficiently large. Therefore, as the brush wears, the biasing force pressing the brush against the commutator changes relatively significantly. For this reason, the amount of change in the abrasion amount in which the brush can be used, that is, the usable time of the brush, that is, the service life is shortened within a range where the loss due to the brush does not increase.

As another problem, the brush holding structure using the above-described leaf spring-shaped support member cannot further flatten the motor. In other words, for DC motors,
There is a motor in which a yoke for magnetically connecting a pair of field poles provided on both sides of an output shaft is flattened and a cross-sectional shape of a motor is flattened. Such flattening of the cross-sectional shape can reduce the space occupied by the motor without lowering the torque. However, in the brush holding structure using the leaf spring-shaped support member, the length of the elastic displacement portion needs to be as long as possible, which is an obstacle to further flattening the motor.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object thereof is to provide a brush holding structure for a motor in which a brush is held by a leaf spring-like member and is urged against a commutator. The object of the present invention is to make the motor flat while keeping the life of the brush as long as possible.

It is another object of the present invention to provide a brush holding housing having the brush holding structure and a motor having the brush holding housing.

[0009]

According to a first aspect of the present invention, there is provided a plate spring-like member for holding a brush, wherein the base of the plate spring-like member is on a stator side of a motor. And the elastic displacement portion provided integrally with the base portion is formed so as to extend in a plane perpendicular to the output shaft, and the brush is fixed to the distal end side, and the elastic displacement portion fixes the base portion. In the brush holding structure of the motor in which the leaf spring-like member is supported so as to be displaceable in the plane as an end, the yoke of the motor is formed in a cylindrical shape and has a cross section including a pair of flat portions and a pair of arc portions. And closed the opening of the yoke.
On the brush holding housing, the leaf spring-like member,
Electrically connected to the brush and supplying power to the brush
Receiving side where the power supply side terminal for connection can be connected from the outside
A terminal is provided, the elastic displacement portion is provided so as to extend substantially parallel to both flat portions of the yoke, and a base end thereof is disposed outside at least a position corresponding to an end portion of the flat portion ; The base is almost straight against the flat portions.
The power receiving side terminal is provided so as to extend in the
Is an inner peripheral side of the base, and a commutator of the motor.
It is provided so as to be arranged on the outer peripheral side of . In addition, "the base end is arrange | positioned outside from the position corresponding to the end part of the said flat part at least" means that the base end of an elastic displacement part is
This means that it is located at a position facing the end of the flat portion, or is located outside the flat portion that is not opposed to the flat portion.

[0010] According to a second aspect of the present invention, in the first aspect of the invention, the elastic displacement portion is disposed at a position where a base end thereof does not face the flat portions. According to a third aspect of the present invention, in the first or second aspect of the present invention, the brush holding housing includes the leaf spring member.
And gold provided with the power receiving side terminal electrically non-conductive
A substrate formed of a metal body, wherein the substrate is
Fixed to the opening in a state of being electrically connected to the yoke.
An insulating portion is provided on an inner surface of the substrate;
A brush holder comprising the above leaf spring-shaped member
The brush holder supports the leaf spring-shaped member.
And a support portion arranged parallel to the output shaft.
A flat portion to be placed, and a leaf spring-shaped portion above the flat portion.
The base of the material is opposite to the output shaft side in the flat part
A holding piece is provided for pressing and holding in contact with
Have been .

[0011] According to a fourth aspect of the invention, there Bei Ete brush holding structure according to 請 Motomeko 3.

According to a fifth aspect of the present invention, in the fourth aspect of the present invention, the shaft supporting portion is rotatably supported with one end of the output shaft being in contact with the substrate. Is provided.

According to a sixth aspect of the present invention, in the fourth or fifth aspect of the invention, when the field magnet is fixed to the opening of the yoke, the field magnet moves from a predetermined position to the opening side. A positioning portion is provided to abut the field magnet so as not to move.

According to a seventh aspect of the present invention, there is provided the brush holding housing according to any one of the fourth to sixth aspects. (Operation) According to the first aspect of the present invention, the length of the elastic displacement portion, which is greatly related to the change in the urging force with respect to the wear amount of the brush, is ensured within the range of the cross section of the flat yoke. At the same time, the yoke can be flattened while keeping the length of the elastic displacement portion as much as possible. Therefore, it is possible to flatten the entire motor without increasing the amount of change in the urging force with respect to the amount of wear of the brush. Also, the motor bias
The power supply terminal is connected from outside without obstructing
Power receiving side terminal is provided.

According to the invention described in claim 2, according to claim 1
In addition to the operation of the invention described in the above, since the base end of the elastic displacement portion is disposed at a position not opposed to the flat portion, the length of the elastic displacement portion is maximized and the length of the elastic displacement portion is reduced. It is possible to further flatten the brush holding portion while securing the maximum.

According to the third aspect of the invention, the first aspect is provided.
Alternatively, in addition to the function of the invention described in claim 2, the yoke and
The casing formed by the brush holding housing
The entire magnetic circuit inside the motor is electromagnetically shielded .

According to the invention described in claim 4, according to claim 3,
Has the same effect as the effect of the invention described in (1) . According to the fifth aspect of the invention, in addition to the function of the fourth aspect, the output shaft is electrically connected to the casing that electromagnetically shields the entire motor.

According to the invention described in claim 6, according to claim 4,
Alternatively, in addition to the operation of the invention described in claim 5, when the brush holding housing is assembled to the opening of the yoke, the field magnet is positioned so as not to move toward the opening by the positioning portion provided in the brush holding housing. You.

According to the seventh aspect of the present invention, the brush holding housing forming the motor has the function of the fourth aspect of the present invention.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. FIG. 2 shows the motor 1
It is a plane cross section at the central axis of 0. As shown in FIG.
The motor 10 includes a yoke 11 and a lid 12 as a brush holding housing. The yoke 11 is formed in a cylindrical body having one side closed and an opening 11 a provided on the other side, and the opening 11 a is closed by a lid 12.

FIG. 3 is a sectional view taken along line AA of FIG. As shown in FIG. 3, the yoke 11 has a pair of flat portions 13 whose shapes in a plane cross section perpendicular to the central axis are parallel to each other.
The right and left circular arc portions 14 are formed. Inside the yoke 11, a pair of field magnets 15 formed so as to be in close contact with the inner side surfaces of the respective arc portions 14 are housed.

As shown in FIG. 2, each field magnet 15 has a positioning portion 1 interposed between the field magnet 15 and a bottom wall 11b of the yoke 11.
6 is positioned at a predetermined fixed position separated from the bottom wall 11b by a predetermined distance. Yoke 11 and lid 12
An armature (armature core and windings) 18 is fixed to the output shaft 17 supported by. A commutator 19 is provided on the output shaft 17 closer to the lid 12 than the armature 18.

FIG. 1 is a perspective view showing the lid 12. As shown in FIG. 1, the lid 12 is
A substrate 20 as a metal body having a shape conforming to a is provided. The board 20 is made of a metal plate, and a connector portion 21 (shown in FIG. 2) made of a synthetic resin is provided on an outer surface thereof, and an insulating portion 22 is provided on an inner surface thereof. Substrate 20
Is formed by, for example, press punching from a metal plate, and the connector portion 21 and the insulating portion 22 are integrally formed by outsert molding.

On the insulating part 22, a bearing 23 is provided as a shaft supporting part made of, for example, metal. Bearing 23
As shown in FIG. 2, the output shaft 17 is provided so as to be supported in a state where the end of the output shaft 17 is in contact with the substrate 20, that is, in a state where the output shaft 17 and the substrate 20 are electrically connected. .

On the insulating portion 22, brush holders 24 are provided on both sides of the bearing 23. Brush holder 24
Are caulked and fixed to a fixing projection 25 provided on the insulating portion 22, as shown in FIG.

FIG. 4 shows the brush holder 24. The brush holder 24 includes a substrate 26 fixed to the insulating portion 22 and a leaf spring-like member 27 supported by the substrate 26. Substrate 2
6 is a base portion 2 that is in contact with the insulating portion 22 as shown in FIG.
8, a supporting portion 29 that supports the leaf spring-like member 27, and a female terminal portion 30 as a power receiving terminal. The substrate 26 is formed of a metal plate material having spring properties.

The base 28 has a hole 31 into which the fixing projection 25 is fitted. The support portion 29 includes a flat portion 32 arranged parallel to the central axis of the bearing 23. Above the flat portion 32, a holding piece 33 for pressing and holding the leaf spring-like member 27 in contact with the front side of the flat portion 32 is provided. The holding piece 33 is formed integrally with the support portion 29, and is formed so as to press the leaf spring-like member 27 toward the front side of the flat portion 32 by its spring property. In the plane part 32,
In order to prevent the holding piece 33 from being elastically deformed when the leaf spring-like member 27 is not held, a hole 34 for releasing the tip is provided.

Also, as shown in FIG.
On the left side in the X-axis direction, a pair of upper and lower convex portions 35 for positioning the leaf spring-like member 27 held in contact with the flat portion 32 in the Z-axis direction and restricting movement to the −X side is provided. Is formed. Similarly, a pair of upper and lower cut-and-raised portions 36 for positioning the leaf spring-like member 27 in the Z-axis direction is formed on the right side of the plane portion 32 in the X-axis direction. Further, the flat spring portion 32 is fixed between the pair of convex portions 35 by the leaf spring-like member 27 which is in contact with the both convex portions 35 and positioned in the X-axis direction so as not to move to the + X side. Are provided.

As shown in FIG. 2, the female side terminal portion 30 has a hole 4 formed through the connector portion 21 and the insulating portion 22.
2 is formed so as to be able to pinch a flat power supply terminal T which is inserted from the outside through the power supply terminal 2.

On the other hand, as shown in FIG. 6, the leaf spring-like member 27 is provided so as to extend from the end of the base 38 to the + Y side in the Y-axis direction. Elastic displacement portion 39 and elastic displacement portion 39
And a brush 40 fixed to the tip side of the brush. The leaf spring-like member 27 is formed by bending a metal plate having spring properties.

The base portion 38 is formed in a flat plate shape extending in the X-axis direction and in close contact with the flat portion 32. Base 38
The width in the Z-axis direction is between the two convex portions 35 and both the cut-and-raised portions 3
6 and are formed so as to fit each other.
It is formed in a shape in which movement in the X direction is regulated by the two convex portions 35. The base 38 is provided with an engaging hole 41 with which the convex locking part 37 is engaged.

The elastic displacement portion 39 is formed so that its base end extends from the end of the base 38 to the + Y side in the Y-axis direction, and its distal end side moves toward the -X side in the X-axis direction with respect to the base end. It is formed to extend to the side.

As shown in FIG. 4, the leaf spring-like member 27
In a state where the base portion 38 is in contact with the flat portion 32 of the base portion 26 with respect to the support portion 29, the base portion 38 is positioned in the Z-axis direction by the both convex portions 35 and the both cut-and-raised portions 36, and the two convex
And it is supported in a state where it is positioned in the X-axis direction by the convex locking portion 37.

As shown in FIG. 1, the leaf spring-like member 27
The elastic displacement portion 39 is provided to extend substantially parallel to the flat portion 13 of the yoke 11 with the brush 40 in contact with the outer peripheral surface of the commutator 19. The leaf spring-like member 27 is
The elastic displacement portion 39 is provided such that the base end thereof is disposed outside of between the flat portions 13.

The leaf spring-like member 27 is provided so that the base 38 extends in a direction substantially perpendicular to both flat portions 13.
The female terminal 30 is arranged on the inner peripheral side of the base 38.
Further, as shown in FIG. 1, a pair of support portions 43 extending in the center axis direction of the bearing 23 are provided integrally with the insulating portion 22 for each brush holder 24 on the lid 12. The support portions 43 are provided so as to abut against the support portions 29 of the substrate 26 from the inside to prevent the flat portion 32 from falling toward the commutator 19.

A positioning portion 44 extending in the central axis direction of the bearing 23 is provided integrally with the insulating portion 22 for each brush holder 24 on the lid 12. The positioning unit 44
As shown in FIG.
Each field magnet 15 positioned at a predetermined position in the direction of the central axis is provided so as to abut against the field magnet 15 so as not to move toward the opening 11a.

As described in detail above, according to this embodiment, the following operations and effects can be obtained. (A) The elastic displacement portion 39 of the leaf spring-like member 27 that holds the brush 40 is provided so as to extend substantially parallel to the flat portions 13, and its base end is located outside the space between the flat portions 13. I did it. Therefore, within the range of the cross section of the yoke 11 formed flat, the length of the elastic displacement portion 39 greatly related to the change of the urging force with respect to the amount of wear of the brush 40 is secured to the maximum, and the elastic displacement portion 39 The flattening of the motor 11 is possible with the maximum length secured. As a result, it is possible to flatten the motor 10 while extending the life of the brush 40 as much as possible.

(B) The base portion 38 of the leaf spring-like member 27 is provided so as to extend in a direction substantially perpendicular to the flat portion 13.
The female terminal 30 is provided on the inner peripheral side of the base 38. Therefore,
The female terminal 30 can be provided without obstructing the flattening of the motor 10, and the connection of the power supply line to the motor 10 can be easily performed.

(C) Lid 12 with brush holding structure
The substrate 20 was made of a metal plate, and was electrically connected to the yoke 11 in a state where the substrate 20 was assembled to the opening 11 a of the yoke 11. Therefore, the entire magnetic circuit inside the motor 10 is electromagnetically shielded by the casing formed by the yoke 11 and the lid 12, so that leakage of electromagnetic noise from the motor 10 can be reduced.

(D) Since the output shaft 17 is conducted to the casing (yoke 11, lid 12) for electromagnetically shielding the motor 10, electromagnetic noise can be prevented from leaking from the output shaft 17.

(E) When the cover 12 is assembled to the yoke 11, the positioning portion 44 provided on the cover 12
Is positioned at a predetermined fixed position, so that the field magnet 15 can be easily fixed to the yoke 11.

Note that the embodiment is not limited to the above-described embodiment, and may be modified as in the following different examples. The base end of the elastic displacement portion 39 is the flat portion 13 of the yoke 11
The plate-shaped spring member 27 may be provided so as to be disposed at a position opposite to the end of the plate spring. Even in this case, the motor 10 can be flattened while extending the life of the brush 40 as much as possible.

Each of the brush holders 24 has a female terminal 30
May be provided instead of a soldering terminal projecting from the lid 12 to the outside. In this case, the base portion 38 of the leaf spring-like member 27 may be provided, for example, from the base end of the elastic displacement portion 39 toward the commutator 19 side, instead of the direction perpendicular to both flat portions 13.

The yoke 11 may be a cylindrical body having openings on both sides, and lids may be fixed on both sides. In this case, the brush holding structure may be provided on the lid on the side where the output shaft 17 extends outside.

The brush holder 24 may be formed by integrating the substrate 26 and the leaf spring-like member 27. The plate spring-like member 27 is replaced with the substrate 26 and the insulating portion 22 is used.
May be supported by a structural unit provided integrally with the camera.

Further, the power receiving side terminal is supported by a structural part provided integrally with the insulating part 22, and a leaf spring-like member 27 is formed by a wiring pattern or the like.
May be conducted. The bearing of the shaft support is not limited to the metal bearing 23, but may be a rolling bearing (bearing).

The metal body forming the lid 12 is not limited to a metal plate pressed and stamped, but may be one formed by casting, forging, or the like. -Instead of using the brush holding housing as the cover 12 that constitutes the casing, the casing is formed by the yoke and the lid that is not provided with the brush holding structure, and is provided separately from the lid and housed in the casing. The present invention may be applied to a brush holding structure in a brush holding body that has been used. In this case, since electromagnetic shielding is not required, it can be formed of a synthetic resin instead of a metal body.

The motor is not limited to a motor whose casing is formed by a yoke, but may be a motor having a casing provided separately from the yoke. Hereinafter, it is understood from the above-described embodiment and each different example.
Technical ideas other than the inventions described in the claims are described together with their effects.

(1) A motor provided with the brush holding housing according to claim 5, wherein the positioning portion restricts the field magnet from moving toward the opening. According to such a configuration, the field magnet can be easily attached and fixed to the yoke.

[0050]

As described in detail above, according to the first to seventh aspects of the present invention, the motor can be flattened while the life of the brush is made as long as possible. Also outside
The power supply side terminal can be connected from the
Connection of electric wires can be easily performed.

According to the present invention, the motor can be flattened while the life of the brush is further extended .

According to the third to seventh aspects of the present invention, the entire motor can be electromagnetically shielded, and leakage of electromagnetic noise can be reduced. Claims 5 to 7
According to the invention described in (1), the entire motor is electrically connected to the casing for electromagnetically shielding, so that the electromagnetic noise is hardly leaked from the output shaft.

According to the sixth and seventh aspects of the present invention, the field magnet is positioned by attaching the brush holder to the yoke, so that the assembly is facilitated.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a lid provided with a brush holding structure.

FIG. 2 is a schematic plan sectional view showing a motor.

FIG. 3 is a sectional view taken along line AA in FIG. 2;

FIG. 4 is a perspective view showing a brush holder.

FIG. 5 is a perspective view showing a substrate.

FIG. 6 is a perspective view showing a leaf spring-like member.

[Explanation of symbols]

10 ... motor, 11 ... yoke, 11a ... opening, 12 ...
Lid as brush holding housing, 13 ... flat part, 1
4 ... Arc part, 15 ... Field magnet, 17 ... Output shaft, 19 ... Commutator, 20 ... Substrate as metal body, 23 ... Bearing as shaft support part, 27 ... Plate spring member, 30 ... Power receiving side terminal Female terminal part, 38 ... base part, 39 ... elastic displacement part, 40
... brush, 45 ... positioning part, T ... power supply side terminal.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) H02K 13/00

Claims (7)

(57) [Claims] 1. A leaf spring-like member for holding a brush,
The base of the leaf spring-shaped member is fixed to the stator side of the motor, and an elastic displacement portion provided integrally with the base is formed so as to extend in a plane perpendicular to the output shaft. Is fixed, and the elastic displacement portion has the base portion as a fixed end, and the leaf spring-like member is supported so as to be displaceable in the plane. The yoke of the motor is formed in a cylindrical shape. A brush holding housing having a flat cross section having a pair of flat portions and a pair of arc portions, and closing an opening of the yoke.
And electrically connected to the leaf spring-like member and the brush.
Power supply terminal for supplying power to the brush
A power receiving side terminal connectable to the yoke, the elastic displacement portion is provided so as to extend substantially parallel to both flat portions of the yoke, and a base end thereof is at least opposed to an end of the flat portion. It is arranged outside from a position, wherein the base extends in a direction substantially perpendicular to the two flat portions
The power receiving side terminal is provided on the inner peripheral side of the base.
And disposed on an outer peripheral side of a commutator of the motor.
The brush holding structure in the motor provided as follows. 2. The brush holding structure for a motor according to claim 1, wherein a base end of the elastic displacement portion is disposed at a position not opposed to the flat portions. 3. The brush holding housing according to claim 1 , wherein
Negative member and power receiving side terminal are provided in an electrically non-conductive state
A substrate formed of a metal body, wherein the substrate is
It is fixed to the opening of the yoke in a state where it is electrically connected to the yoke.
The insulating portion is provided on the inner surface of the substrate,
A bra comprising the leaf spring-like member on the insulating portion
A brush holder , wherein the brush holder supports the leaf spring-shaped member;
Wherein the support portion is a plane disposed parallel to the output shaft.
And a base portion of a leaf spring-shaped member on the upper side of the flat portion.
Abutted on the opposite side to the output shaft side in the plane portion
The brush holding structure of the motor according to claim 1, further comprising a holding piece for pressing and holding the brush in a state. Includes a brush holding structure according to claim 4] 請 Motomeko 3
Brush holding housings. 5. The brush holding housing according to claim 4, wherein a shaft support portion is provided so as to rotatably support one end of the output shaft in a state of being in contact with the substrate . 6. A positioning portion for contacting the field magnet so that the field magnet does not move from a predetermined position toward the opening when fixed to the opening of the yoke. The brush holding housing according to claim 4 or 5. 7. A motor comprising the brush holding housing according to claim 4. Description: