JP2000023434A - Dc motor with brush - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a DC motor with brush in which noise absorbing capacitors can be fixed easily in such a way that the capacitors are not moved by vibrations. SOLUTION: A brush holding plate 12 in the cover section 3 of a DC motor is provided with a pair of capacitor housing chambers between a lead wire lead-out section 25 and a stopper wall section 28 on both sides of the extension of a partition wall section 27. In each chamber, the noise absorbing capacitor on the corresponding side is housed. An insulation pressure plate 36 is arranged at the position at which the plate 36 covers a pair of lead wire lead-out grooves and the capacitor housing chambers on the side of the lead wire lead-out section 25 opposite to the brush press plate 12. The pressure plate 36 has a pair of wire pressure projections 38 which are respectively inserted into the lead wire lead-out grooves to press led-out lead wires 23 in the grooves and capacitor lead wires 31b on the other side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brushed DC motor having a noise absorbing capacitor for suppressing generation of noise due to rectified sparks of the brush DC motor.

[0002]

2. Description of the Related Art FIGS. 5 to 8 show the structure of a conventional brushed DC motor. FIG. 5 is a longitudinal sectional view of a main part of a conventional brushed DC motor, and FIG. FIG. 7 is an explanatory view showing a connection state between a conductive wire of a brush and an external lead wire in a conventional example, and FIG. 8 is a front view of a brush holding plate in a conventional example.

[0003] This DC motor with a brush has a substantially cylindrical metal housing 1 such as iron as shown in the figure. The housing 1 includes a housing main body 2 formed in a substantially cylindrical shape, and a rear cover 3 that closes an end of the housing main body 2. A rotor 4 is provided in the housing 1.
And the stator 5 are arranged.

[0004] The rotor 4 includes a rotor core 7 fixed to the outer periphery of the rotating shaft 6 and an armature winding 8 wound around a slot of the rotor core 7. A commutator 9 is fixed to the outer periphery of the rotating shaft 6, and the armature winding 8 is connected to the commutator 9. The rotating shaft 6 is rotatably supported by a bearing 10 provided at the center of the inner surface of the rear cover 3.

[0005] The stator 5 comprises a housing body 2 also serving as a yoke, and a permanent magnet 11 fixed to the inner periphery thereof.

A brush holding plate 12 is disposed inside the cover 3 of the housing 1 so as to be adjacent to the commutator 9.
As shown in FIG. 8, the brush holding plate 12 is formed by fitting a pair of brushes 14 that come into contact with the commutator 9 with a hole 13 that loosely penetrates the rotating shaft 6.
A pair of brush holding portions 15 for slidably holding the brush 4 in the radial direction of the commutator 9, a plurality of mounting holes 16 through which screws for mounting are passed, and a conducting wire 17 called a pigtail connected to each brush 14. For this purpose, a pair of conductive wire holding walls 18 and 19 provided on each side, and a spring holding projection 21 for holding a spring 20 for urging the brush 14 are provided. The brush holding plate 12 is fixed to the housing 1 by screwing a screw 22 passing through each mounting hole 16 into a screw hole of the rear cover 3. A proximal end of an external lead wire 23 is connected to a distal end of each conductive wire 17 by a crimping fitting 24.

[0007] The brush holding plate 5 is also provided with a lead wire lead-out portion 25. The lead wire deriving unit 25 includes:
A pair of lead wire lead-out grooves 26 is provided for leading out a pair of external lead wires 23. Each lead wire lead-out groove 26 is formed in a size that does not allow the crimp fitting 24 to come out. In the lead wire lead-out portion 25, a partition wall portion 27 is provided between the pair of lead wire lead-out grooves 26 so as to extend in a direction opposite to the lead-out direction of the external lead-out wires 23 (to the commutator 9 side). A stopper wall portion 28 is provided at an end of the partition wall portion 27 in the extending direction in a direction orthogonal to the stopper wall portion 28. Lead wire outlet groove 2
6 is exposed to the outside through a window 29 provided on the peripheral wall of the rear cover 3 of the housing 1, and the external lead-out wires 23 are respectively led out through lead-leading grooves 26.

[0008] In such a DC motor with a brush, the generation of noise due to the commutation spark generated at the commutator 9 and each brush 14 contacting the commutator 9 is suppressed by a noise absorbing capacitor. .

FIGS. 9 to 11 show a main part of a configuration of a brushed DC motor having a conventional noise absorbing capacitor. FIG. 9 shows a conventional brushed DC motor having a conventional noise absorbing capacitor. FIG. 10 is a configuration diagram of a noise absorption circuit, FIG. 10 is an explanatory diagram showing a connection state of a brush lead wire, an external lead wire, and a noise absorption capacitor in a brushed DC motor having a conventional noise absorption capacitor, and FIG. FIG. 4 is a front view showing a state in which components are incorporated in a brush holding plate by a brushed DC motor having the noise absorbing capacitor of FIG.

In the brushed DC motor provided with such a noise absorbing capacitor, as shown in the figure, a pair of noise absorbing capacitors 30 is configured such that one end of one capacitor lead wire 31a is connected to the end of the conducting wire 17 and the outside. The crimping fitting 24 is connected together with the base end of the lead wire 23,
The other capacitor lead wire 31b of the pair of noise absorbing capacitors 30 is mutually connected by a common ground crimp terminal 32, and the ground crimp terminal 32 is connected to the rear cover 3 of the metal housing 1 as a ground member. It is attached by doing. The external lead wire 23 is connected to the DC power supply E.

[0011]

However, the following problems have been encountered in the brushed DC motor provided with the conventional noise absorbing capacitor having such a structure.

(A) Since each of the noise absorbing capacitors 30 is floating from the brush holding plate 12, these noise absorbing capacitors 30 are easily moved by vibration, and each of the noise absorbing capacitors 30 moves. When,
The capacitor lead wires 31a and 31b may be broken due to fatigue due to vibration.

(B) Each of the noise absorbing capacitors 3
If 0 moves, the conductive wire 17 and the crimp terminal for ground 32 come into contact with each other, and the conductive wire 17 may be grounded.

(C) When an external force is applied to push each lead wire 23 out, each lead wire 17 is lifted,
Each noise absorbing capacitor 30 and the conducting wire 17 may rise and come into contact with other nearby metals.

(D) Each of the noise absorbing capacitors 30 is
It is conceivable to fix to the brush holding plate 12 with an adhesive so as not to move due to vibration. However, in this case, many steps are required for the bonding operation, and there is a problem that the cost increases.

An object of the present invention is to provide a brushed DC motor which can easily fix a noise absorbing capacitor so as not to move due to vibration.

Another object of the present invention is to provide a DC motor with a brush which can easily fix the noise absorbing capacitor and the conductive wire of the brush so as not to move due to vibration.

[0018]

SUMMARY OF THE INVENTION The present invention is directed to a rotor and a stator disposed in a metal housing, a brush holding plate fixed in a metal cover of the housing, and a brush holding plate fixed to the brush holding plate. A pair of brushes held and in contact with a commutator provided on the rotor, a pair of conductive wires electrically connected to the brushes, and a brush holding plate having a base end connected to a distal end of each of the conductive wires; And a pair of brushes generated at a contact portion between the commutator and a pair of external lead wires led out through a pair of lead wire lead grooves provided in parallel with the lead wire lead portion. And a pair of noise absorbing capacitors for absorbing noise transmitted to the side, and each of the noise absorbing capacitors is connected to the leading end of one of the capacitor leads and the proximal end of the lead wire and the base end of the external lead wire on the corresponding side. Pressure The other ends of the capacitor lead wires are connected to each other by a common ground crimp terminal and grounded, and the lead wire lead-out portion of the brush holding plate is connected between a pair of lead wire lead-out grooves. A partition wall portion is provided to extend in a direction opposite to the lead-out direction of the external lead wire, a stopper wall portion is provided at an end of the partition wall portion in an extending direction in a direction orthogonal to the partition wall portion, and a pair of conductive wires is a brush holding plate. The present invention is to improve a brushed DC motor disposed between a pair of conducting wire holding walls provided in the motor.

In the brush-equipped DC motor according to the present invention, the brush holding plate is provided with a pair of capacitor accommodating chambers on both sides of the extended portion of the partition wall and between the lead wire lead-out portion and the stopper wall. Have been. Each of these capacitor accommodation chambers accommodates a corresponding noise absorbing condenser. The pair of lead wire lead-out grooves accommodate an external lead wire on each side and the other capacitor lead wire, and are led out of the cover. The ground crimp terminal to which the other capacitor lead wire is commonly connected is electrically connected to the outer surface of the cover outside the cover. The lead wire lead-out portion is provided with a holding plate positioning portion. On the side facing the brush holding plate via the lead wire lead-out portion, at a position where the pair of lead wire lead-out grooves and the pair of capacitor accommodating chambers are closed, an insulating holding plate is provided with a holding plate positioning portion of the lead wire lead-out portion. It is positioned and arranged with the presser plate positioning portion of the insulating presser plate. The insulating holding plate is provided with a pair of wire holding projections respectively inserted into the pair of lead wire leading grooves to hold the internal external lead wire and the other capacitor lead wire.

As described above, the brush holding plate is provided with a pair of capacitor housing chambers on both sides of the extension of the partition wall and between the lead wire lead-out section and the stopper wall. Accommodates a noise absorbing capacitor,
Pressing the upper part with an insulating holding plate makes it possible to easily fix the noise absorbing capacitor so that it does not move due to vibration. Therefore, fatigue disconnection of the capacitor lead wire due to vibration of the noise absorbing capacitor can be prevented. Further, the insulating holding plate includes a pair of wire holding protrusions respectively inserted into the pair of lead wire leading grooves, and the wire holding protrusions allow the external lead wire in each lead wire leading groove and the other capacitor. Since the lead wire is held down, it is possible to prevent the external lead wire and the other capacitor lead wire from moving due to vibration or external force. Since the insulating holding plate is positioned at the lead wire lead-out portion by the holding plate positioning portion, the positioning of the insulating holding plate with respect to a required position becomes easy, and the insulating holding plate moves during use. Can also be reliably prevented.

In this case, it is preferable that the insulating holding plate is provided with a conductor-side cover that closes a space between the conductor-holding walls. With this configuration, it is possible to prevent the brush wires from jumping out due to vibration of the conductive wires.

[0022]

1 (A), 1 (B) through 4 show an example of an embodiment of a brushed DC motor provided with a noise absorbing capacitor according to the present invention. (B) is a rear view and a side view of a rear cover part used in the brushed DC motor of this embodiment, in which parts are incorporated, FIG. 2 is a front view of only this rear cover part, and FIG. 4A is a front view of a brush holding plate used in a DC motor, FIG. 4A is a bottom view of an insulating holding plate attached to the brush holding plate in this example, and FIG. 4B is a left side view of FIG. is there. Parts corresponding to those in FIGS. 5 to 11 described above are denoted by the same reference numerals.

In the brush-equipped DC motor having the noise absorbing capacitor of this embodiment, as shown in FIG. 10, the pair of noise absorbing capacitors 30 is connected to the tip of one capacitor lead 31a. The crimping fitting 2 together with the distal end of the conducting wire 17 and the proximal end of the external lead wire 23
4 and a pair of these noise absorbing capacitors 30
The other capacitor lead wires 31b are connected to each other by a common ground crimp terminal 32, and the ground crimp terminal 32 is connected to the rear cover 3 of the metal housing 1 as a grounding member. I have.

In the brushed DC motor provided with such a noise absorbing capacitor 30, the brush holding plate 5 is provided on both sides of the extension of the partition 27 and between the lead wire lead-out portion 25 and the stopper wall 28. Is provided with a pair of capacitor housing chambers 33. Each of the capacitor-accommodating chambers 33 accommodates a corresponding one of the noise absorbing capacitors 30 on the corresponding side.

In the pair of lead wire lead-out grooves 26 in the lead wire lead-out portion 25, the external lead wire 23 on each side and the other capacitor lead wire 31b are accommodated and led out of the rear cover part 3. . The crimp terminal 32 for grounding, which connects the other capacitor lead wire 31b in common,
Outside the rear cover 3, it is electrically connected to the outer surface of the rear cover. In this example, the ground crimping terminal 32 is fitted to a protruding portion of the screw 22 that fixes the brush holding plate 12 by screwing it into the screw hole 3 a of the rear cover portion 3 from the rear cover portion 3. Electrically and mechanically connected.

On the partition 27 of the lead wire lead-out section 25,
A presser plate positioning portion 35 composed of a pair of protrusions is provided. Further, in this example, the outer conductor holding wall 18 of the pair of conductor holding walls 18 and 19 for holding the conductor 17 is extended toward the lead wire lead-out portion 25 and integrated.

On the side facing the brush holding plate 12 via the lead wire lead-out portion 25, an insulating holding plate 36 is provided at a position where the pair of lead wire lead-out grooves 26 and the pair of capacitor housing chambers 33 are closed.
Are positioned and positioned by the convex holding plate positioning portion 35 of the lead wire lead-out portion 24 and the concave holding plate positioning portion 37 of the insulating holding plate 36. The insulation holding plate 36 has 1
The internal lead-out lead 23 and the other capacitor lead 31b are inserted into the pair of lead lead-out grooves 26, respectively.
Are provided.
The insulating holding plate 36 has conductive wire holding walls 18, 19.
The conductor-side cover portion 36a that closes the space therebetween is provided.

In the brush-equipped DC motor provided with such a noise absorbing capacitor, the brush holding plate 5 is provided on both sides of the extension of the partition 27 and between the lead wire lead-out portion 25 and the stopper wall 28. One pair of condenser storage rooms 3
3 are provided, and the corresponding noise absorbing capacitors 30 are accommodated in the capacitor accommodating chambers 33, and the noise absorbing capacitors 30 are pressed thereon by the insulating holding plate 36. Therefore, each noise absorbing capacitor 30 is easily fixed so as not to move due to vibration. be able to. For this reason, fatigue disconnection of the capacitor lead wires 31a and 31b due to vibration of the noise absorbing capacitor 30 can be prevented. The insulating holding plate 36 includes a pair of wire holding protrusions 38 respectively inserted into the pair of lead wire leading grooves 36, and the wire holding protrusions 38 use the respective lead wire leading grooves 36.
Since the external lead wire 23 and the other capacitor lead wire 31b are held down, it is possible to prevent the external lead wire 23 and the other capacitor lead wire 31b from moving due to vibration or external force. This insulating holding plate 36
The positioning of the insulating holding plate 36 with respect to a required position is facilitated by the positioning of the insulating holding plate 36 at the required position by the holding plate positioning portions 35 and 37, and the insulating holding plate 36 moves during use. Can also be reliably prevented. Further, the insulation pressing plate 36 has the conductor pressing wall 18,
Since the conductor-side cover portion 36a that blocks the space between 19 is provided, it is possible to prevent the brushes 14 from jumping out due to the vibration of the conductor 17.

[0029]

In the brush-equipped DC motor according to the present invention, one portion is provided on both sides of the extended portion of the partition wall with respect to the brush holding plate and between the lead wire lead-out portion and the stopper wall.
A pair of capacitor storage chambers are provided, and the capacitor for noise absorption on the corresponding side is stored in these capacitor storage chambers, and it is held down by an insulating holding plate, so it is easily fixed so that the noise absorption capacitor does not move due to vibration can do.
Therefore, fatigue disconnection of the capacitor lead wire due to vibration of the noise absorbing capacitor can be prevented. Also,
The insulating holding plate includes a pair of wire holding protrusions respectively inserted into a pair of lead wire leading grooves, and these wire holding protrusions provide an external lead wire in each lead wire leading groove and the other capacitor lead wire. Therefore, it is possible to prevent the external lead wire and the other capacitor lead wire from moving due to vibration or external force. Since the insulating holding plate is positioned at the lead wire lead-out portion by the holding plate positioning portion, the positioning of the insulating holding plate with respect to a required position becomes easy, and the insulating holding plate moves during use. Can also be reliably prevented.

[Brief description of the drawings]

FIGS. 1A and 1B are a rear view and a side view of a rear cover part in which components of an example of an embodiment of a brushed DC motor having a noise absorbing capacitor according to the present invention are incorporated.

FIG. 2 is a front view of only a rear cover shown in FIG.

FIG. 3 is a front view of a brush holding plate used in the brushed DC motor of the present embodiment.

FIG. 4A is a bottom view of an insulating holding plate attached to a brush holding plate in this example, and FIG. 4B is a left side view of FIG.

FIG. 5 is a vertical sectional view of a main part showing the structure of a conventional brushed DC motor.

FIG. 6 is a sectional view taken along line XX of FIG. 5;

FIG. 7 is an explanatory diagram showing a connection state between a conductive wire of a brush and an external lead wire in a conventional example.

FIG. 8 is a front view of a brush holding plate in a conventional example.

FIG. 9 is a configuration diagram of a noise absorbing circuit in a DC motor with a brush provided with a conventional noise absorbing capacitor.

FIG. 10 is an explanatory view showing a connection state of a brush lead wire, an external lead wire, and a noise absorbing capacitor in a DC motor with a brush having a conventional noise absorbing capacitor.

FIG. 11 is a front view showing a state in which components are incorporated in a brush holding plate in a brushed DC motor having a conventional noise absorbing capacitor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Housing 2 Housing main body 3 Rear cover part 4 Rotor 5 Stator 6 Rotating shaft 7 Rotor core 8 Armature winding 9 Commutator 10 Bearing 11 Permanent magnet 12 Brush holding plate 13 Hole 14 Brush 15 Brush holding part 16 Mounting hole 17 Conductors 18, 19 Conductor holding wall 20 Spring 21 Spring holding protrusion 22 Screw 23 External lead wire 24 Crimp fitting 25 Lead wire lead portion 26 Lead wire lead groove 27 Partition wall 28 Stopper wall 29 Window 30 Noise absorbing capacitor 31 a One of them Capacitor lead wire 31b The other capacitor lead wire 32 Crimping terminal for ground 33 Capacitor storage chamber 34 Nut 35 Holding plate positioning portion 36 Insulating holding plate 36a Conductor side cover portion 37 Holding plate positioning portion 38 Wire holding protrusion

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) JJ03 JJ06 JJ11 LL02 LL06 LL07 LL13

Claims (2)

[Claims] A rotor and a stator disposed in a metal housing; a brush holding plate fixed in a metal cover of the housing; and a rotor held by the brush holding plate. A pair of brushes for contacting the provided commutator, a pair of conductive wires electrically connected to the pair of brushes, and a base end connected to a distal end of the pair of conductive wires to hold the brush A pair of external lead-out leads led out through a pair of lead-out lead grooves provided in parallel with the lead lead-out portion of the plate; A pair of noise absorbing capacitors for absorbing noise transmitted to the pair of brushes;
The pair of noise-absorbing capacitors are connected by crimping fittings together with the leading end of the lead wire and the base end of the external lead wire on the side corresponding to the leading end of each of the one capacitor lead wires, and each of the other capacitor lead wires. Are connected to each other by a common ground crimping terminal and grounded, and a lead-out portion of the brush holding plate is provided with a partition wall between the pair of lead-out grooves so as to lead out the external lead-out wire. The partition wall portion is provided to extend in a direction opposite to the direction, and an end of the partition portion in the extension direction is provided with a stopper wall portion in a direction perpendicular to the extension direction, and the pair of conductive wires is provided in a pair with the brush holding plate. In the brush-equipped DC motor arranged between the conductive wire holding walls, the brush holding plate includes the lead wire lead-out portion and the stopper wall portion on both sides of an extension of the partition. A pair of capacitor accommodating chambers are provided in a portion between the two, and the capacitor accommodating chambers accommodate the respective noise absorbing capacitors on the corresponding side, and the pair of lead wire lead-out grooves include the outer side on each side. The lead-out lead wire and the other capacitor lead wire are accommodated and led out of the cover portion, and the ground crimp terminal commonly connecting the other capacitor lead wire is provided outside the cover portion. It is electrically connected to the outer surface of the cover part, and the lead wire lead-out part is provided with a pressing plate positioning part,
On the side opposite to the brush holding plate via the lead wire lead-out portion, an insulating holding plate is provided at a position for closing the pair of lead wire lead-out grooves and the pair of capacitor accommodating chambers. A positioning portion and a positioning plate positioning portion of the insulating holding plate are positioned and arranged. The insulating holding plate is inserted into the pair of lead wire lead-out grooves, respectively, and has an internal external lead wire and the other capacitor. A brushed DC motor, comprising a pair of wire holding projections for holding a lead wire. 2. The DC motor with a brush according to claim 1, wherein the insulating holding plate is provided with a conductor-side cover for closing a space between the conductor-holding walls.