JP2009027807A - Commutator motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a motor 1 which suppresses deterioration in commutation by maintaining a brush 3 and a commutator in an excellent and stable contact state. <P>SOLUTION: The commutator surface 8 in contact with a brush 3 is inclined to the surface orthogonal to the axis of an armature 2. A brush holder 6 has a brush insertion hole 6a to allow the brush 3 to insert therethrough, wherein the brush insertion hole 6a is formed in the direction vertical to the armature surface 8. Thus, the brush 3 is inserted into the brush insertion hole 6a to be slidably retained in the direction vertical to the commutator surface 8, and is brought into contact with a brush spring 7 vertically to the commutator surface 8. The brush 3 is vertically brought into contact with the commutator surface 8 having an inclination angle α to stably press the brush 3 to the commutator surface 8. As a result, the contact state between the commutator surface 8 and the brush 3 can be excellently maintained, suppressing deterioration of commutation. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a commutator motor having a commutator and a brush.

As a prior art, there is a rotating electric machine described in Patent Document 1.
As shown in FIG. 4, this rotating electrical machine forms a commutator by using an end portion of an armature coil 100 that constitutes a coil end, and axially extends on the surface of the commutator (referred to as a commutator surface 110). To the brush 120. The brush 120 is slidably held by a resin brush holder 130 and is pressed against the commutator surface 110 by a brush spring 140 housed in the brush holder 130.
In addition, the end of the armature coil 100 forming the commutator is provided with a substantially equal cross-sectional area from the outer diameter side to the inner diameter side of the armature 150. It is formed so as to gradually become thicker from the inner diameter side toward the inner diameter side. Therefore, the commutator surface 110 with which the brush 120 contacts is provided to be inclined by a predetermined angle α with respect to the surface orthogonal to the axis of the armature 150.
JP 2004-187436 A

However, in the above prior art, the brush 120 is pressed against the inclined commutator surface 110 in parallel (axial direction) with the axis of the armature 150. That is, since the end surface of the brush 120 (the surface that contacts the commutator surface 110) is inclined according to the inclination of the commutator surface 110, the brush 120 is parallel to the commutator surface 110 (outer diameter direction). A component force of the brush spring 140 is generated. Due to the action of this component force, the brush 120 is easily lifted from the commutator surface 110, causing deterioration of rectification and causing a decrease in performance.
Further, since the brush 120 is pressed against the inner surface of the brush holder 130 due to the component force acting in the outer diameter direction, the strength of the brush holder 130 needs to be increased. As a result, the thickness of the brush holder 130 is increased, resulting in a high material cost.
The present invention has been made based on the above circumstances, and an object of the present invention is to provide a commutator motor that can suppress deterioration of commutation by maintaining a good and stable contact state between the brush and the commutator. There is to do.

(Invention of Claim 1)
The present invention relates to a commutator provided in an armature, a brush that comes into sliding contact with the commutator as the armature rotates, a brush spring that presses the brush against the commutator, a brush holder that holds the brush, and the brush holder The commutator motor is configured such that the surface of the commutator with which the brush is in sliding contact is inclined with respect to a plane perpendicular to the axis of the armature, and the brush holder has the brush inside There is a brush insertion hole to be inserted, and this brush insertion hole is formed in a direction perpendicular to the surface of the commutator, and the brush is inserted into the brush insertion hole and slides in a direction perpendicular to the surface of the commutator. It is held freely and pressed perpendicularly to the surface of the commutator by a brush spring. The meaning of “vertical” according to the present invention includes a range of ± 3 ° with respect to a vertical line that intersects the commutator surface at a right angle.

According to the above configuration, even when the surface of the commutator (referred to as a commutator surface) is inclined with respect to a surface orthogonal to the axis of the armature, the brush is pressed perpendicularly to the commutator surface. That is, since a component force is not generated in a direction parallel to the commutator surface with respect to the load of the brush spring, the brush is not pressed against the inner surface of the brush holder, and the brush can be stably pressed against the commutator surface. As a result, the brush does not float from the commutator surface, and the contact state between the two is kept good, so that deterioration of rectification can be suppressed.
In addition, since the load of the brush spring is not dispersed and the entire load is applied to the brush in a direction perpendicular to the commutator surface, the load of the brush spring can be reduced as compared with the prior art (Patent Document 1). The life of the brush spring can be expected to be improved by reducing the stress.
Furthermore, since the brush is not pressed against the inner surface of the brush holder, the strength of the brush holder can be reduced and the thickness can be reduced, and the material cost can be reduced accordingly.

(Invention of Claim 2)
The commutator motor according to claim 1, wherein a brush spring is housed in the brush insertion hole, and a bottom surface of the brush insertion hole that receives an end of the brush spring on the side opposite to the brush is formed in parallel with the surface of the commutator. It is characterized by.
In this case, one end of the brush spring that urges the end surface of the brush and the other end of the brush spring that contacts the bottom surface of the brush insertion hole can be formed in parallel, so there is no need to manufacture a new brush spring, (For example, a JIS standard product) brush spring can be used. Even if the brush spring rotates in its circumferential direction, the pressing force for urging the brush does not change, and the brush can be stably pressed perpendicularly to the commutator surface.

(Invention of Claim 3)
The commutator motor according to claim 1 or 2, wherein the end frame is integrally provided with a concave holder holding portion for holding the brush holder, and the brush holder is fitted into the holder holding portion. It is characterized by that.
In this case, since it is not necessary to provide the brush holder integrally with the end frame, for example, the holder holding portion can be formed integrally with the end frame by die-casting and can be manufactured by die cutting in one direction.
Further, since the brush holder is fitted into the holder holding portion and attached, for example, it is not necessary to use parts such as metal fittings and screws, and the cost can be reduced.

(Invention of Claim 4)
The present invention relates to a commutator provided in an armature, a brush that comes into sliding contact with the commutator as the armature rotates, a brush spring that presses the brush against the commutator, and a brush holder that holds the brush via a guide member. A commutator motor configured such that the surface of the commutator with which the brush is in sliding contact is inclined with respect to a plane perpendicular to the axis of the armature, and the brush holder is provided integrally with the end frame, and A mounting hole for mounting the guide member is formed, the guide member has a cylindrical shape with both ends open, a brush is slidably inserted therein, and is perpendicular to the surface of the commutator. The brush is attached to the mounting hole in an inclined manner so that the brush can move. The brush is slidably held in the vertical direction with respect to the surface of the commutator via the guide member, and the brush spring. Characterized in that it pressed perpendicularly to the surface of the commutator by. The meaning of “vertical” according to the present invention includes a range of ± 3 ° with respect to a vertical line that intersects the commutator surface at a right angle.

According to the above configuration, even when the surface of the commutator (referred to as a commutator surface) is inclined with respect to a surface orthogonal to the axis of the armature, the brush is pressed perpendicularly to the commutator surface. That is, since no component force is generated in the direction parallel to the commutator surface with respect to the load of the brush spring, the brush is not pressed against the inner peripheral surface of the guide member, and the brush can be stably pressed against the commutator surface. . As a result, the brush does not float from the commutator surface, and the contact state between the two is kept good, so that deterioration of rectification can be suppressed.
In addition, since the load of the brush spring is not dispersed and the entire load is applied to the brush in a direction perpendicular to the commutator surface, the load of the brush spring can be reduced as compared with the prior art (Patent Document 1). The life of the brush spring can be expected to be improved by reducing the stress.

Further, since the brush is not pressed against the inner surface of the guide member, the strength of the guide member can be reduced and the thickness can be reduced, and the material cost can be reduced accordingly.
Since the guide member can be made into a simple cylindrical shape by pressing from an iron plate or the like, the cost can be kept low. In addition, since the guide member has a cylindrical shape, a gap is formed inside the brush holder, so that heat transmitted from the brush does not stay inside the brush holder, and it is easy to dissipate heat, improving the heat resistance of the guide member. .

(Invention of Claim 5)
5. The commutator motor according to claim 4, wherein the brush holder has a spring chamber that houses a brush spring, the spring chamber is formed continuously with the mounting hole, and an end portion of the brush spring on the side opposite to the brush The bottom surface of the spring chamber is configured to be parallel to the surface of the commutator.
In this case, one end of the brush spring that urges the end surface of the brush and the other end of the brush spring that contacts the bottom surface of the brush insertion hole can be formed in parallel, so there is no need to manufacture a new brush spring, (For example, a JIS standard product) brush spring can be used. Even if the brush spring rotates in its circumferential direction, the pressing force for urging the brush does not change, and the brush can be stably pressed perpendicularly to the commutator surface.

  The best mode for carrying out the present invention will be described in detail with reference to the following examples.

In the first embodiment, an example in which the commutator motor of the present invention (hereinafter referred to as motor 1) is used as a starter will be described.
FIG. 1 is a half sectional view of a motor portion used in a starter.
The starter has a known function of starting the engine by transmitting rotational torque generated by the motor 1 from a pinion gear (not shown) to an engine ring gear (not shown).
The motor 1 is a known commutator having a commutator (described below) and a brush 3 for switching the current flowing through the armature 2 according to the rotation phase so that the built-in armature 2 can rotate in a certain direction. It is an electric motor.

The commutator is configured using a coil end of an armature coil.
As shown in FIG. 1, the armature coil has two types of coil conductors (an inner coil conductor 4 and an outer coil conductor 5) formed in advance in a substantially U shape and inserted into the slot of the armature 2. After being assembled into two layers, the end portions of the inner coil conductor 4 and the outer coil conductor 5 inserted into slots having different circumferential directions are electrically joined by welding or the like.
Here, the outer coil conductor 5 includes a coil straight portion 5a inserted into the slot, and a pair of coil end portions 5b extending from both ends of the coil straight portion 5a to bend toward the inner diameter side of the armature 2, respectively. A commutator is formed using one (right side in the drawing) of the coil end portions 5b of the set of coil end portions 5b.

The brush 3 is held by a brush holder 6 which will be described below, and an end face (referred to as a commutator face 8) on the outer side in the axial direction of one coil end 5 b by a brush spring 7 housed in the brush holder 6. ).
However, one coil end 5b forming the commutator has an axial direction (left-right direction in the figure) from the outer diameter side in order to provide substantially the same cross-sectional area from the outer diameter side to the inner diameter side of the armature 2. It is formed so as to gradually become thicker toward the inner diameter side. That is, the commutator surface 8 against which the brush 3 is pressed is provided so as to be inclined by an angle α with respect to a surface orthogonal to the axis OO of the armature 2 as shown in FIG.

The brush holder 6 is made of, for example, an insulating material such as resin, and is fixed to an end frame 9 that closes the rear portion of the motor 1. The brush holder 6 has a brush insertion hole 6 a for inserting the brush 3 therein, the brush insertion hole 6 a is formed in a direction perpendicular to the commutator surface 8, and the brush spring 7 has an anti-brush side. A bottom surface 6 b of the brush insertion hole 6 a that receives the end of the first end is formed in parallel with the commutator surface 8. Therefore, the brush 3 is inserted into the brush insertion hole 6 a, is held so as to be slidable in the vertical direction with respect to the commutator surface 8, and is pressed perpendicularly to the commutator surface 8 by the brush spring 7.
The end frame 9 is made of, for example, a metal such as aluminum, and is fitted and assembled to an end side (opposite engine side) opening of the motor yoke 10, and at the end side end of the armature shaft 2 a via the bearing 11. The part is supported rotatably.

(Effect of Example 1)
In the above configuration, the brush 3 is pressed perpendicularly to the commutator surface 8 having the inclination angle α. In this case, no component force is generated in the direction parallel to the commutator surface 8 with respect to the load of the brush spring 7, so that the brush 3 is not pressed against the inner surface of the brush holder 6, and the brush 3 is stably rectified. It can be pressed against the child face 8. As a result, the brush 3 does not float from the commutator surface 8, and the contact state between the commutator surface 8 and the brush 3 is kept good, so that deterioration of commutation can be suppressed.
Further, since the load of the brush spring 7 is not dispersed and the entire load is applied to the brush 3 in a direction perpendicular to the commutator surface 8, a conventional technique in which a component force acts on the brush 3 in the outer diameter direction (patent) Compared with literature 1), the load of the brush spring 7 can be reduced. As a result, the life of the brush spring 7 can be expected to be improved by reducing the stress.

Furthermore, since the brush 3 is not pressed against the inner side surface of the brush holder 6, the material cost can be reduced as much as the strength of the brush holder 6 can be reduced and the thickness can be reduced.
Further, the brush holder 6 has a brush insertion hole 6a formed in a direction perpendicular to the commutator surface 8, but the bottom surface 6b of the brush insertion hole 6a (surface receiving the end of the brush spring 7 on the side opposite to the brush). Since the commutator surface 8 is formed in parallel, both end surfaces of the brush spring 7 can be formed in parallel. In this case, it is not necessary to newly manufacture the brush spring 7, and a standard product (for example, JIS standard product) brush spring 7 can be used. Further, even if the brush spring 7 rotates in its circumferential direction, the pressing force for urging the brush 3 does not change, and the brush 3 can be stably pressed perpendicularly to the commutator surface 8.

FIG. 2 is a half sectional view of a motor portion used in the starter.
As shown in FIG. 2, the brush holder 6 shown in the second embodiment is fitted and attached to a holder holding portion 9 a provided on the end frame 9.
The holder holding portion 9a is provided in a concave shape that opens in the axial direction from the axial end face of the end frame 9, and is molded integrally with the end frame 9 by, for example, a die casting method.
As in the first embodiment, the brush holder 6 is made of an insulating material such as resin, has a brush insertion hole 6a formed in a direction perpendicular to the commutator surface 8, and a holder holding portion provided in the end frame 9. It has the fitting part 6c fitted by 9a. In addition, the holder holding part 9a and the fitting part 6c, for example, form the holder holding part 9a in a box-shaped concave shape, and form the fitting part 6c in a box-shaped convex shape, thereby fitting the two into an uneven shape. Thus, the fitting portion 6c is provided so as not to rotate inside the holder holding portion 9a.

  According to the above configuration, the brush 3 does not lift from the commutator surface 8 and the contact state between the commutator surface 8 and the brush 3 is kept good as in the first embodiment. it can. Further, since the fitting portion 6c of the brush holder 6 is fitted and attached to the inside of the holder holding portion 9a provided on the end frame 9, in order to fix the brush holder 6 to the end frame 9, for example, metal fittings, screws, etc. It is not necessary to use these parts, and the cost can be reduced. Furthermore, since the holder holding portion 9a is provided in a concave shape that opens in the axial direction from the axial end surface of the end frame 9, the holder holding portion 9a can be integrally formed with the end frame 9 by, for example, a die casting method. Moreover, it can be manufactured by die cutting in one direction.

FIG. 3 is a half sectional view of a motor portion used in the starter.
In the third embodiment, as shown in FIG. 3, a brush holder 12 is provided on the end frame 9, and the brush 3 is held on the brush holder 12 via a guide member 13.
The end frame 9 is integrally provided with a brush holder 12 having a concave shape. The brush holder 12 is formed with an attachment hole 12a for attaching the guide member 13 and a spring chamber 12b for accommodating the brush spring 7. Has been.

The guide member 13 has a cylindrical shape with both ends open, the brush 3 is slidably inserted into the guide member 13, and the brush 3 can move in a direction perpendicular to the commutator surface 8. It is attached to the attachment hole 12a formed in the state inclined.
The brush 3 is slidably held in the vertical direction with respect to the commutator surface 8 via the guide member 13, and is pressed perpendicularly to the commutator surface 8 by the brush spring 7.
The spring chamber 12 b is formed continuously with the attachment hole 12 a, and the bottom surface 12 c of the spring chamber 12 b that receives the end of the brush spring 7 on the opposite brush side is formed in parallel with the commutator surface 8.

According to the above configuration, the brush 3 does not lift from the commutator surface 8 and the contact state between the commutator surface 8 and the brush 3 is kept good, as in the first embodiment. it can. Further, since the load of the brush spring 7 is not dispersed, the load of the brush spring 7 can be reduced, and the life of the brush spring 7 can be expected to be improved by reducing the stress.
Furthermore, since the guide member 13 can be formed into a simple cylindrical shape by press molding from an iron plate or the like, and the brush 3 is not pressed against the inner peripheral surface of the guide member 13, the thickness of the guide member 13 can be reduced. It is possible to keep costs low. In addition, since the guide member 13 has a cylindrical shape, a gap is formed inside the brush holder 12, so that heat transmitted from the brush 3 is not trapped inside the brush holder 12, and heat is easily radiated. Heat resistance is improved.

  Further, since the brush holder 12 has a bottom surface 12c of the spring chamber 12b (a surface receiving the end of the brush spring 7 opposite to the brush side) formed in parallel with the commutator surface 8, as in the case of the first embodiment. The both end surfaces of the brush spring 7 can be formed in parallel. Thereby, it is not necessary to newly manufacture the brush spring 7, and a standard product (for example, JIS standard product) brush spring 7 can be used. Further, even if the brush spring 7 rotates in its circumferential direction, the pressing force for urging the brush 3 does not change, and the brush 3 can be stably pressed perpendicularly to the commutator surface 8.

  The brush holder 12 shown in the third embodiment is provided integrally with the metal end frame 9, and the end of the brush spring 7 is in contact with the bottom surface 12 c of the spring chamber 12 b formed in the brush holder 12. . For this reason, when the metal brush spring 7 is used, the brush 3 and the end frame 9 are electrically connected through the brush spring 7. Therefore, the brush holder 12 shown in the third embodiment can be applied to the negative brush 3. On the other hand, when applied to the brush 3 on the plus side, for example, the brush spring 7 can be made of an insulating material such as resin. Alternatively, the brush holder 6 shown in Example 1 or Example 2 may be used.

  In the first to third embodiments, the expressions “perpendicular to the commutator surface 8” and “perpendicular to the commutator surface 8” are used. It shall include a range of ± 3 ° with respect to a perpendicular line intersecting at a right angle.

(Example 1) which is a semi-sectional view of the motor part used for a starter. (Example 2) which is a semi-sectional view of the motor part used for a starter. (Example 3) which is a semi-sectional view of the motor part used for a starter. It is a half sectional view of a motor part used for a starter (prior art).

Explanation of symbols

1 Motor (commutator motor)
2 Armature 3 Brush 5b One coil end (commutator)
6 Brush holder (Examples 1 and 2) 6a Brush insertion hole 6b Bottom surface of brush insertion hole 7 Brush spring 8 Commutator surface (commutator surface)
9 End frame 9a Holder holding part 12 Brush holder (Example 3)
12a Mounting hole 12b Spring chamber 12c Bottom surface of spring chamber 13 Guide member

Claims (5)

A commutator provided in the armature;
A brush slidably contacting the commutator as the armature rotates;
A brush spring that presses the brush against the commutator;
A brush holder for holding the brush;
An end frame to which the brush holder is attached;
The commutator motor is configured such that the surface of the commutator in sliding contact with the brush is inclined with respect to a plane orthogonal to the axis of the armature,
The brush holder has a brush insertion hole for inserting the brush therein, and the brush insertion hole is formed in a direction perpendicular to the surface of the commutator,
The brush is inserted into the brush insertion hole, is slidably held in a direction perpendicular to the surface of the commutator, and is pressed perpendicularly to the surface of the commutator by the brush spring. Characteristic commutator motor. In the commutator motor according to claim 1,
The brush spring is housed in the brush insertion hole, and the bottom surface of the brush insertion hole that receives the end of the brush spring opposite to the brush is formed in parallel with the surface of the commutator. Commutator motor. In the commutator motor according to claim 1 or 2,
The end frame is integrally provided with a concave holder holding portion for holding the brush holder,
The brush holder is attached by being fitted into the holder holding portion. A commutator provided in the armature;
A brush slidably contacting the commutator as the armature rotates;
A brush spring that presses the brush against the commutator;
A brush holder for holding the brush via a guide member;
The commutator motor is configured such that the surface of the commutator in sliding contact with the brush is inclined with respect to a plane orthogonal to the axis of the armature,
The brush holder is provided integrally with the end frame, and an attachment hole for attaching the guide member is formed,
The guide member has a cylindrical shape with both ends open, the brush is slidably inserted into the guide member, and the brush is movable in a direction perpendicular to the surface of the commutator. It is attached to the hole in an inclined state,
The brush is slidably held in the vertical direction with respect to the surface of the commutator via the guide member, and is pressed perpendicularly to the surface of the commutator by the brush spring. Commutator motor. In the commutator motor according to claim 4,
The brush holder includes a spring chamber that houses the brush spring. The spring chamber is formed continuously with the mounting hole, and receives the end of the brush spring on the side opposite to the brush. Is formed in parallel with the surface of the commutator.

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