JP2009177904A - Brush unit for motor, and motor with brush - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide brush units for a motor that flatten the motor with a brush. <P>SOLUTION: The brush units 20, 30 have a forked brush piece 21 contacting with a rectifier 8 so as to be slidable, and a brush terminal 22 which fixedly holds the brush piece, and is embedded in a resin-made bottom lid 4 which is fit to a motor case 1. The brush terminal 22 has a first insertion fixing piece 22b having a first locking protrusive piece F<SB>1</SB>at a lower part with one side of a connecting plate 22a bent and curved, and a second insertion fixing piece 22c having a second locking protrusive piece F<SB>2</SB>at a lower part with the other side of the connecting plate 22a bent and curved. The first insertion fixing piece 22b and the second insertion fixing piece 22c face each other via a groove 22d, and the forked brush piece 21 is face-joined to the first insertion fixing piece 22b at its one side, and oriented in parallel with the extension direction of the groove 22d. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a structure of a brush unit in a motor with a brush and a support structure for the brush unit.

As a brush unit used for a small motor, for example, as disclosed in Japanese Patent Laid-Open No. 9-215278, a brush piece that is in sliding contact with a commutator and a bottom lid that is fixedly held by the brush piece and fitted into a motor case are installed. The brush terminal piece has a locking projection that exerts an anchor effect, and is fixed by being inserted into the through hole of the bottom lid.
JP-A-9-215278 (FIGS. 1 and 2)

  However, in the brush terminal piece in which the locking projection is caught on the hole wall of the through hole, the insertion depth of the brush terminal piece into the through hole is suppressed in order to prevent the brush terminal piece from falling down, which affects the orthogonality of the brush piece to the commutator. Therefore, the depth of the through-hole, that is, the thickness of the bottom cover must be increased, and this obstructs the flattening of the small motor.

  Then, in view of the said problem, the subject of this invention is providing the brush unit for motors which can achieve flattening of the motor with a brush.

  In order to solve the above-mentioned problems, the present invention is for a motor having a brush piece that is in sliding contact with a commutator, and a brush terminal that is fixedly held in the brush and is embedded in a resin bottom lid that fits into a motor case. In the brush unit, the brush terminal is bent at one side of the connecting plate portion and has a first insertion fixing piece having a first locking protrusion on the lower side, and is bent at the other side of the connecting plate portion and moved downward. A second insertion fixing piece having two locking protrusions, the first insertion fixing piece and the second insertion fixing piece facing each other through a groove, and the brush piece has one end side thereof It is characterized in that it is surface-bonded to the first insertion fixing piece and oriented parallel to the extending direction of the groove.

  In the brush unit for a motor having such a structure, the brush terminal forms a groove portion by the first insertion fixing piece having the first locking projection piece and the second insertion fixing piece having the second locking projection piece. Because it is configured in a bifurcated shape, the support strength of the brush terminal can be increased even if the insertion depth of each insertion fixing piece to the resin bottom lid is short, so the thickness of the resin bottom lid can be reduced. Further, the brushed motor can be flattened.

  Here, in the motor with a brush using the brush unit for motor, the first and second insertion grooves corresponding to the first and second insertion fixing pieces, and the first and second locking protrusions are provided. Resin bottom having corresponding first and second through-holes and an outer surface side wiring recess for drawing out the lead wire connected to the locking protrusion protruding from at least one of the through-holes in the radial direction of the motor case It is desirable to use a lid.

  The lead wire connected to the locking protrusion of the insertion fixing piece can be pulled out in the radial direction of the motor case through the inside of the resin-side bottom-side wiring housing recess. Thus, a motor with a brush can be mounted, and the mounting height can be suppressed at least by the wire diameter of the lead wire.

  Furthermore, the resin bottom cover corresponds to a caulking recess for pressing and bending the lower edge of the motor case inward to a part on the outer surface side of the outer periphery, and a caulking recess on the inner surface side of the outer periphery. It is desirable to have the reinforcing convex part piled up in the position.

  The reinforcing convex part is formed on the inner surface side of the outer peripheral edge at a position corresponding to the caulking concave part. Therefore, when the lower end edge of the motor case is caulked and fixed to the caulking concave part, the resin bottom cover is thin. But it can suppress cracks.

  Embodiments of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a cutaway perspective view showing a motor with a flat brush according to an embodiment of the present invention, FIG. 2 is an assembly perspective view of the motor with a flat brush, and FIG. 3A is a brush with the motor with the flat brush. FIG. 3B is a perspective view showing the outer surface side of the bottom cover with the brush, and FIG. 4 is a bottom view of the motor with the flat brush.

  The motor with a flat brush of this example includes a motor case 1 that holds a metal bearing 2 on a burring portion 1a and an annular magnet 3 on an inner peripheral surface, and a resin bottom lid 4 that closes the lower end side opening of the motor case 1. And have. The resin bottom lid 4 has a central recess 4a in which the receiving plate 5 and the metal bearing 6 are fitted on the inner surface side thereof. The rotor includes a commutator 8 fixed to the shaft 7 and a coil 10 wound around the laminated core 9.

The resin bottom lid 4 supports the first and second brush units 20 and 30 arranged at a brush angle of 90 ° on the inner surface side thereof. Each of the brush units 20 and 30 has the same configuration, and as shown in FIGS. 5 to 7, a bifurcated brush piece 21 slidably contacting the commutator 8, and the bifurcated brush piece 21 are fixedly held to hold the resin bottom It has a brush terminal 22 implanted in the lid 4 and a vibration damper 23 fixed to the base side of the forked brush piece 21. The brush terminal 22 is an inverted U-shaped (reverse U-shaped) bent plate, bent on one side of the connecting plate portion 22a, and has a first insertion fixing piece 22b having a _first locking projection F1 below, It has a second insertion fixing piece 22c having a _second locking projection F2 bent downward by bending the other side of the connecting plate portion 22a, and the first insertion fixing piece 22b and the second insertion fixing piece 22c. Face each other through the groove 22d. Each of the locking protrusions F ₁ and F ₂ is formed with a return portion T that exhibits an anchor effect at both edges thereof, and a round hole H for inserting and soldering a lead wire end. have. One end of the bifurcated brush piece 21 is surface-bonded to the first insertion fixing piece 22b with the two projections W attached, and is oriented parallel to the extending direction of the groove 22d. Due to the notch S formed at the corner, the width dimension of the first insertion fixing piece 22b is shorter than the width dimension of the second insertion fixing piece 22c.

The resin bottom lid 4 that supports the brush units 20 and 30 has a trapezoidal shape for holding the first and second brush units 20 and 30 by being built up in an island shape at 90 ° arrangement on the inner surface side. First and second brush support portions 40 and 50 are provided. Each of the brush support portions 40 and 50 includes first and second insertion grooves 41 and 42 corresponding to the first and second insertion fixing pieces 22b and 22c, and the first and second insertion grooves 41 and 42, respectively. A crowning convex portion 43 that is partitioned and into which the groove portion 22d fits, and is formed in the back of the first and second insertion grooves 41 and 42, and corresponds to the first and second locking projections F ₁ and F ₂ . 1 and a second through-hole _h 1, and a _{h 2.}

Plastic bottom cover 4 is connected at one end to the first second round hole H of the locking projection F ₂ round hole H and the second brush units 30 of the locking projection F ₁ of the first brush unit 20 And a fan-shaped outer surface side wiring housing recess 60 for drawing out the lead wires L ₁ and L ₂ through the narrow portion 61 in the radial direction of the motor case 1. Further, a caulking concave portion V having a gradient for pressing and bending the lower end edge of the motor case 1 inward is formed every 90 ° on the outer surface side of the outer peripheral edge. Z is for inserting a pin for bringing the forked brush piece 21 in advance so that the forked brush piece 21 is properly placed on the peripheral surface of the commutator 8 when the motor case 1 is closed with the resin bottom lid 4. This is a work hole.

In such a motor with a brush, the brush terminal 22 of each brush unit 20, 30 has a first insertion fixing piece 22b having a _first locking projection piece F1 and a _second locking projection piece F2. Since the groove 22d is formed with the second insertion fixing piece 22c and the fitting area is widened, the insertion fixing pieces 22b and 22c are inserted into the insertion grooves 41 and 42 of the resin bottom lid 4 respectively. Even if the insertion depth is short, the support strength of the brush terminal 22 can be increased, so that the thickness of the resin bottom lid 4 can be reduced and the motor with brush can be flattened. Since the two protrusions W also fit into the first insertion groove 41, the fixing strength can be increased.

Further, the lead wires L ₁ and L ₂ connected to the locking protrusions F ₁ and F ₂ of the insertion fixing pieces 22 b and 22 c are connected to the motor case 1 via the inside of the outer surface side wiring housing recess 60 of the resin bottom lid 4. Since it can be pulled out in the radial direction, the motor with a brush can be mounted with the resin bottom lid 4 in close contact with the substrate or equipment, and the mounting height can be suppressed at least by the wire diameter of the lead wires L ₁ and L ₂ . The solder terminal B shown in FIG. 4 can prevent the brush terminal 22 from coming off from the first and second insertion grooves 41 and 42.

  FIG. 8 is a perspective view showing an inner surface side of another brushed bottom cover used for the flat brushed motor. In the resin bottom lid 4 ′, the reinforcing convex portion 65 is formed at a position corresponding to the caulking concave portion V on the inner surface side of the outer peripheral edge. For this reason, when the lower end edge of the motor case 1 is caulked and fixed to the caulking recess V, cracks and the like can be suppressed even with the resin bottom lid 4 'having a small thickness.

1 is a cutaway perspective view showing a flat brush motor according to an embodiment of the present invention. It is an assembly perspective view of the motor with the flat brush. (A) is a perspective view which shows the inner surface side of the bottom cover with a brush in the same flat motor with a brush, (B) is a perspective view which shows the outer surface side of the bottom cover with the brush. It is a bottom view of the motor with a flat brush. (A) is the perspective view which shows the brush unit used for the motor with the same flat brush, (B) is the perspective view which looked at the brush unit from the back side. (A) is a plan view of the brush unit, (B) is a front view of the brush unit, and (C) is a bottom view of the brush unit. (A) is a rear view of the brush unit, (B) is a right side view of the brush unit, and (C) is a left side view of the brush unit. It is a perspective view which shows the inner surface side of another bottom cover with a brush used for the same motor with a flat brush.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Motor case 1a ... Burring part 2, 6 ... Metal bearing 3 ... Ring magnet 4, 4 '... Resin bottom cover 4a ... Central recessed part 5 ... Base plate 7 ... Shaft 8 ... Commutator 9 ... Laminated core 10 ... Coil 20 ... first brush unit 21 ... bifurcated brush piece 22 ... brush terminal 22a ... connecting plate portion 22b ... first insertion fixing piece 22c ... second insertion fixing piece 22d ... groove 23 ... damping damper 30 ... second Brush unit 40 ... first brush support portion 41 ... first insertion groove 42 ... second insertion groove 43 ... crowning projection 50 ... second brush support portion 60 ... outer surface side wiring housing recess 61 ... narrow portion 65 ... reinforcing protruding portion B ... solder _{F 1} ... first locking projections _{F 2} ... second locking protrusion H ... round hole _{h 1} ... first through hole _{h 2} ... second through-hole _L 1, L 2 _... leads S ... notch T ... barb V ... concave for the caulking W ... projections Z ... work for long hole

Claims (3)

In a brush unit for a motor having a brush piece that is in sliding contact with the commutator, and a brush terminal that is fixedly held on the resin case and that is fitted on the motor case and fitted to the motor case,
The brush terminal includes a first insertion fixing piece that is bent on one side of the connecting plate portion and has a first locking protrusion on the lower side, and a second lower portion on the other side of the connecting plate portion that is bent downward. A second insertion fixing piece having a locking protrusion, the first insertion fixing piece and the second insertion fixing piece facing each other through a groove, and the brush piece has one end thereof A brush unit for a motor, characterized in that the side is surface-bonded to the first insertion fixing piece and oriented parallel to the extending direction of the groove. The motor with a brush using the brush unit for a motor according to claim 1, wherein the resin bottom cover includes first and second insertion grooves corresponding to the first and second insertion fixing pieces, First and second through holes corresponding to the first and second locking protrusions, and lead wires connected to the locking protrusions protruding from at least one of the through holes in the radial direction of the motor case A motor with a brush having an outer surface side wiring housing recess for drawing out. 3. The motor with brush according to claim 2, wherein the resin-made bottom cover includes a caulking concave portion that is fixed by pressing and bending a lower end edge of the motor case to a part of an outer surface side of the outer peripheral edge thereof, and the outer peripheral edge. A brushed motor comprising: a reinforcing convex portion built up at a position corresponding to the caulking concave portion on the inner surface side of the brush.

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