JP2003164116A - Brush device for small motor and manufacturing method thereof - Google Patents

Abstract

[PROBLEMS] To set a brush holder holding a brush or a brush fixing portion after assembling a case, a rotor and an end bell, and to set a brush sliding portion on a commutator. A brush holder supports two brush opening pins provided corresponding to two brush arms, and the brush opening pins are located on opposite sides of the two brush arms and correspond to each other. When a force acts in the brush arm side direction, the brush arms are configured to abut against each other and open to each other. The end bell side wall is provided with a protrusion configured to engage the brush opening pins and cause them to open in the direction of opening each other, and to release the engagement in the final mating position. After inserting the integrally assembled rotor into the metal case, an end bell is fitted to close the opening of the metal case, and then a brush holder is fitted and attached to the end bell opening.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brush device for a small motor, in which a brush sliding portion can be easily and surely set on a commutator, and a manufacturing method thereof.

[0002]

2. Description of the Related Art In the assembly of a conventional small-sized motor, a case having a hollow cylindrical shape with a bottom and made of a metal material and having a magnet as a stator magnetic pole attached, a rotor magnetic pole and a commutator are integrally assembled on a shaft. Prepare the rotor and the end bell to which the brush arms supporting the two brushes are attached respectively, and after inserting the rotor integrally assembled on the shaft from the opening of this case, open the opening of the case. It was done by fitting the end bell so that it would close. Since an elastic force is applied to the brush arm in the direction in which the two brushes come into contact with each other, when the end bell is fitted, it is necessary to bring the two brush sliding parts into contact with each other on the commutator with the sliding parts open. There is.

As a method of opening the brush sliding portion of a small motor and setting it on the commutator, a brush opening pin with a dedicated jig is inserted from the end bell opening, and the commutator of the rotor is opened with the brush open. Is set at a predetermined position, the brush is closed, and then the brush opening pin is removed.

However, such a brush setting method is
It is necessary to provide an opening for inserting a special jig such as a brush opening pin for setting the brush sliding portion on the commutator. In particular, when a waterproof function is required as in the case of using a small motor for a power window of an automobile, it is necessary to separately seal the opening. Further, it is difficult to set the brush or the brush holder holding the brush fixing portion after assembling the case, the rotor and the end bell.

FIG. 8 is a diagram showing another conventional brush setting method (Japanese Utility Model Laid-Open No. 4-61467). When the brush body is assembled to the brush housing, the guide flange formed on the brush body is assembled along the end surface of the brush guide. The guide flange is
It is provided on the brush holding plate to which the brush is attached. The figure shows the brush as being in three intermediate positions during brush assembly. The brush at the first position in the figure shows a state in which the brush inserted from below into the brush housing is now in contact with the brush guide. At the second brush position in the figure, it is shown that the guide flange slides along the end surface of the brush guide as the brush body moves upward, thereby generating a force to open the brush to the left and right. Then, in the third brush position in the figure, the brush is in the most opened state, and when it is further raised a little, the guide flange is separated from the engagement with the brush guide. As a result, the brush comes into contact with the commutator. It will be.

However, such a brush setting method is
Since the brush guide acts substantially directly on the brush holding plate to which the brush is attached to open it,
(Carbon) May cause damage to the brush itself. Moreover, there is a problem that it is not possible to easily discover that damage has occurred after it has been incorporated. Further, due to the direct action of the brush guide and the guide flange in this way, when a failure occurs, it cannot be disassembled for repair and reuse.

[0007]

Therefore, the present invention eliminates the need to provide the end bell with an opening for inserting the brush opening pin by a dedicated jig, which allows the present invention to provide a motor without any special parts. The purpose is to enable the end bell part to have a waterproof function.

Further, the present invention eliminates the need for a dedicated jig for setting the brush sliding portion on the commutator, and the brush holding the brush or the brush fixing portion after the case, the rotor (commutator) and the end bell are assembled. The holder can be set and the brush sliding part can be set on the commutator.

Another object of the present invention is to make it easy to assemble the (carbon) brush itself without causing damage, and to disassemble, repair and reuse it when a failure occurs. There is.

[0010]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides a brush holder having a brush opening pin and an end bell having a brush opening pin opening / closing mechanism portion, and a brush fixing portion held by the brush holder. At the same time as setting the brush sliding part on the commutator at the same time as setting the end bell on the end bell, an opening for inserting the dedicated jig for setting the brush sliding part on the commutator and the brush opening pin of the end bell. Is unnecessary.

A brush device for a small-sized motor according to the present invention comprises a bottomed hollow cylindrical metal case to which a stator magnetic pole is attached, an end bell fitted so as to close an opening of the metal case, and a bottom portion of the metal case. A rotor configured by integrally assembling a rotor magnetic pole and a commutator on a shaft that is rotatably supported by bearings provided on the end bell and two brushes that are in contact with the commutator are attached. And a brush holder that supports two brush arms. The brush holder supports two brush opening pins that are provided corresponding to the two brush arms, and the brush opening pins are located inside respective opposite sides of the two brush arms and are arranged in the corresponding brush arm side direction. When a force is applied, the brush arm and the brush supported by the brush arm are opened so as to abut against each other. The end bell is provided with an opening constituted by a side wall extending in a direction perpendicular to the rotor axis direction, and a brush holder is fitted and attached to the end bell opening. Protrusions are provided on the side wall of the end bell that are configured to engage the brush opening pins to act in the direction of opening them together and to release this engagement in the final mating position.

Further, the protrusion has a predetermined height sufficient to engage the tip of the brush opening pin, and its width is such that it is in contact with the brush opening pin at the final insertion position of the brush holder. Until the contact is released, the side faces of the protrusions can be made substantially gradually wider so that the side faces of the protrusions come into contact with the brush opening pins and open them from each other as the brush holder is inserted.

The brush opening pin has a predetermined length extending substantially parallel to the brush arm, and at least the tip of the brush opening pin is brought into contact with the side surface of the protrusion so that the protrusion of the brush opening pin is provided. It is possible to make it into an L-shape that is bent to the side wall side of the end bell opening provided with.

Further, the brush opening pin is integrally molded and fixed to a pedestal integrally molded with the brush holder so as to abut against the extension direction of the brush arm at right angles thereto.

Further, in the method of manufacturing a brush device for a small motor of the present invention, the brush holder supports two brush opening pins provided corresponding to the two brush arms, and the brush opening pins include two brush opening pins. It is located inside each of the arms facing each other, and is configured to abut against the brush arm and open the brush arm and the brush supported by the brush arm when the force acts in the lateral direction of the corresponding brush arm. The end bell is provided with an opening constituted by a side wall extending in a direction perpendicular to the rotor axis direction, and the end bell side wall is engaged with the brush opening pin so that they act in the direction of opening each other, and A protrusion configured to release this engagement is provided at the target mating position. After inserting the rotor integrally assembled into the metal case, the end bell is fitted so as to close the opening of the metal case, and then the brush holder is fitted and fitted into the end bell opening. It is a thing.

[0016]

1 is a view showing the appearance of a small motor to which the present invention is applied, showing a state in which assembly is completed. FIG. 2 is a sectional view of the completed small motor shown in FIG. In both figures, (A) on the left side of the figure shows a front view in which the rotor shaft is viewed laterally,
A side view seen from the end bell side is shown in (B) on the right side of the figure. The small-sized motor 1 of the present invention can be made the same as the conventional structure except for the mounting structure of the end bell portion and the brush. The metal case 15 is formed of a metal material in a hollow cylindrical shape with a bottom, and the magnet 1 as a stator magnetic pole.
7 is attached. The yoke 2 is attached to the outer periphery of the metal case 15. The rotor 3 has a shaft 16
The rotor magnetic pole and the commutator 4 are integrally assembled on the upper side. This rotor 3 has a metal case bottom and an end bell 5.
And rotatably supported by bearings respectively provided on the and. The current supplied from the external power source through the brush and the commutator flows through the windings wound around the rotor magnetic poles, which allows the motor to rotate. The above-described configuration and operation are normal, and a detailed description thereof will be omitted.

A small motor to which the present invention is applied is characterized by a brush holder for mounting a brush and an end bell for mounting the brush holder. After inserting the rotor 3 integrally assembled on the shaft 16 from the opening of the metal case 15 having a hollow cylindrical shape with a bottom, the end bell 5 made of resin is fitted so as to close the opening of the metal case 15. .
In this state, the rotor 3 is rotatably supported, but the brush is not yet in contact with the commutator 4.

As shown in the figure, the end bell 5 is provided with an opening formed by an integrally molded resin side wall extending in a direction perpendicular to the rotor axis direction (lower side in the figure). A brush holder that supports a brush arm to which a brush is attached is fitted and attached to the end bell opening.
At this time, at least a part of the end bell opening must be in a position facing the commutator 4 so that the brush abuts on the commutator. In the process of fitting the brush holder into the opening from the lower side of the drawing, the two brush arms to which the brushes are attached are opened by the feature of the present invention, and finally, the two brushes are placed on the commutator. Will come into contact with. The first example of the brush opening pin will be described below with reference to FIGS. 3 to 5.

FIG. 3 is a view of the same small motor as illustrated in FIGS. 1 and 2, but after fitting the endbell 5 in the metal case 15, but still with the brush holder 9 in the endbell opening. 6 shows a state in which it is not inserted. FIG. 5 is a schematic perspective view for facilitating the understanding of the mutual relationship of the main components. The cross-sectional shape of the end bell opening 6 (the shape viewed from the brush holder insertion side) can be any shape such as a circle, but the illustrated configuration is configured to have a substantially rectangular cross-section. Therefore, the end bell opening 6 is 4
Has four wall surfaces, and these four wall surfaces are
It is composed of two wall surfaces facing each other in the axial direction of the shaft and two wall surfaces facing each other at right angles. The details will be described later on the inner surface of one of the two wall surface portions facing each other in the shaft axial direction of the four wall surface portions (in the example shown, on the inner surface on the side closer to the magnetic pole in the shaft axial direction). The protrusion 7 is provided for engaging the brush opening pin 11 and opening it.

Although not a feature of the present invention, when the brush holder 9 is inserted into the end bell opening 6, the brush holder 9 is properly attached to the inner surface of the wall surface different from the one provided with the protrusion 7. It is possible to appropriately provide one or more line-shaped projections or grooves functioning as guide rails for positioning the brush holders 9 and corresponding line-shaped grooves or projections in the brush holder 9.
Further, it is possible to provide a line-shaped projection that functions to increase the strength of the wall surface portion of the end bell opening made of synthetic resin.

A protrusion 7 that engages with the brush opening pin 11.
Does not need to be high, but has a predetermined height high enough for the tip of the brush opening pin 11 to engage, and
As the brush holder 9 is inserted, the width of the protruding portion 7 is increased so that the side surface of the protruding portion 7 surely abuts the brush opening pin 11 and gradually opens the mutual. However, at the final insertion position of the brush holder 9, the protrusion 7 corresponding to the brush opening pin 11 does not exist, whereby the contact with the brush opening pin 11 is released. in this way,
The protrusion 7 does not necessarily need to be flat in the center of the protrusion 7 as long as the side faces on both sides thereof are configured to properly engage with the brush opening pin 11, and the protrusion 7 may be slightly smaller than the side face height. There is no problem with raising or lowering.

The brush holder 9 has a brush fixing portion 10 for fixing two brush arms 12 each supporting a brush 13. Brush opening pins 11 are fixed to the inside of each of the two opposing brush arms 12 and to the brush fixing portion 10. Brush opening pin 1
1 has a predetermined length in a direction in which the brush arm extends substantially parallel to the brush arm and has a certain elastic force. For example, it can be made of a synthetic resin having a predetermined thickness and a predetermined width. At least the tip of the brush opening pin 11 needs to contact the side surface of the projection 7 provided in the end bell opening. Therefore, it is desirable that the tip end portion of the brush opening pin 11 be formed in an L-shape that is bent toward the side wall side of the end bell opening where the protrusion 7 is provided, and that the bent inside is tapered (FIG. In the drawing of the brush holder 9 of FIG. 3A, only the tip end portion of the brush opening pin 11 bent into the L shape is visible.). Since this portion is tapered, the brush holder 9 can be pulled out even after the motor is completed, and disassembly in the event of a failure becomes possible. Further, when the tip ends of the brush opening pins come into contact with the side surfaces of the protrusions to open each other, they come into contact with the respective brush arms to act to open the brush arms. As shown in FIG.
As shown in the drawing of the brush holder 9 in (B), the tip end portion of the brush opening pin 11 is configured to be wide.

The brush holder 9, including the brush opening pin 11 and the brush fixing portion 10, can be integrally formed of synthetic resin. The brush arm 12 may pass through the brush fixing portion 10 and be electrically and mechanically connected to a terminal (not shown) for external connection, or may be integrally formed with the terminal. With this configuration, when the brush holder 9 is inserted into the end bell opening 6 and attached, the brush opening pin insertion is required to set the brush on the commutator in the conventional configuration. However, in order to ensure the waterproof function, a sealing material such as packing should be inserted in the gap between the brush holder 9 and the end bell opening 6 based on a technique known per se. You can

FIG. 4 is a view of the same small motor as illustrated in FIG. 3, but shows a state in the middle of inserting the brush holder 9 into the end bell opening. The state in which the brush opening pin 11 abuts on the wide portion of the protruding portion 7 so that the brush arm 12 and the brush 13 supported by the brush arm 12 are wide open is illustrated. After that, when the brush holder 9 is further inserted into the end bell opening, the protrusion 7
Is disengaged from the brush opening pin 11, and the final assembled state described above with reference to FIG. 2 is obtained.

The brush opening pin 11 can be configured to hit the brush arm 12 just at the end of the abrasion of the carbon brush. With this configuration, the brush arm and the commutator do not slide after abrasion of the carbon brush. Therefore, as long as the wear of the commutator has not significantly increased, it can be used as a motor by replacing the carbon brush (the carbon brush is softer and wears faster than the commutator, so the replacement as described above is possible). Will lead to reuse of the motor).

The material itself of the brush 13 and the brush arm 12 supporting the brush 13 may be the same as that conventionally used.

6 and 7 are perspective views showing a second example of the brush opening pin, FIG. 6 shows the brush holder before the brush arm is attached, and FIG. 7 is the brush holder with the brush arm attached. Is shown. The configuration illustrated here is
It is the same as the first example described with reference to FIGS. 1 to 5, except for the brush opening pin and its related configuration. However, FIGS. 6 and 7 are shown in the upside-down direction of FIG.

The brush holder 9 is provided with a brush fixing portion 10 for fixing two brush arms 12 each supporting a brush 13 as in the first example. Then, in this second example, the pedestal 14 which is entirely flat is integrally formed of resin so as to extend from the brush fixing portion 10 in the extension direction of the brush arm 12. A printed circuit board can be attached to one surface of the pedestal 14. On the other surface side (the side where the brush arm is located) of this pedestal 14, a pair of brush opening pins 11
Is fixed to the pedestal 14 by integral molding so that the brush arm 12 contacts the extension direction of the brush arm 12 at a right angle.

The brush opening pin 11 configured as described above
When the brush holder 9 is inserted into the end bell opening, a protrusion (not shown in FIGS. 6 and 7) provided on the side wall of the end bell opening is engaged in the same manner as in the first example. Can be combined. Further, similarly to the first example, the inside of the tip of the brush opening pin 11 (the side toward the brush arm base) can be tapered so that the brush holder 9 can be pulled out even after the motor is completed. desirable.

Since the brush opening pin of the second example can be configured to have a shorter length as compared with the first example, it is possible to easily secure the rigidity sufficient to overcome the elasticity of the brush arm. It will be possible. Further, since the brush opening pin of the second example is attached in the direction perpendicular to the brush arm extension direction, it is possible to surely and uniformly act on the brush arm. Further, this also makes it possible to suppress vibration of the brush arm during rotation of the motor and reduce noise. Furthermore, since the brush opening pin is connected to the pedestal when resin-molding the brush opening pin together with the pedestal and the brush fixing portion,
The mold shape is simple.

[0031]

According to the present invention, it is not necessary to provide an end bell with an opening for inserting a brush opening pin by a dedicated jig, and a dedicated jig for setting a brush sliding portion on a commutator. Can be eliminated.

Further, according to the present invention, the case, the rotor (commutator), the brush holder which holds the brush or the brush fixing portion after the end bell is assembled, and the brush sliding portion can be set on the commutator. As a result, not only can the brush sliding portion of the small motor be easily and surely set on the commutator, but the number of steps and the function can be reduced.

Further, according to the present invention, the (carbon) brush itself can be easily assembled without causing damage, and when a failure occurs, it can be disassembled, repaired and reused.

[Brief description of drawings]

FIG. 1 is a diagram showing an appearance of a small motor to which the present invention is applied, showing a state where assembly is completed. (A)
Shows the front view of the rotor shaft in the horizontal direction,
(B) shows a side view as seen from the end bell side.

FIG. 2 is a cross-sectional view of the completed small motor shown in FIG.

FIG. 3 is a view of the same small motor as illustrated in FIGS. 1 and 2, but after fitting the endbell to the metal case, but without inserting the brush holder into the endbell opening. Is shown.

FIG. 4 is a view of the same small motor as illustrated in FIG. 3, but showing a state in the middle of inserting the brush holder into the end bell opening.

FIG. 5 is a schematic perspective view for facilitating the understanding of the mutual relationship of the main components.

FIG. 6 is a perspective view showing a second example of the brush opening pin, showing the brush holder before attachment of the brush arm.

FIG. 7 is a perspective view showing a second example of the brush opening pin, showing the brush holder with the brush arm attached.

FIG. 8 is a diagram showing a brush setting method according to a conventional technique.

[Explanation of symbols]

1 Small motor 2 York 3 rotor 4 commutator 5 End bell 6 End bell opening 7 Projection 9 Brush holder 10 Brush fixing part 11 Brush opening pin 12 brush arms 13 brushes 14 pedestal 15 metal case 16 shafts 17 magnets

Claims (8)

[Claims] 1. A bottomed hollow cylindrical metal case to which a stator magnetic pole is attached, an end bell fitted to close an opening of the metal case, and a bottom portion of the metal case and the end bell. A rotor configured to integrally assemble a rotor magnetic pole and a commutator on a shaft rotatably supported by a bearing, and two brush arms having two brushes abutting on the commutator, respectively. And a brush holder for a small motor, the brush holder supporting two brush opening pins provided corresponding to the two brush arms, the brush opening pins facing each other of the two brush arms. When the force is applied to the corresponding brush arm sideward, the brush arm contacts the brush arm and the brush arm and it The held brushes are configured to open each other, and the end bell is provided with an opening formed by a side wall extending in a direction perpendicular to the rotor axis direction, and the brush holder is fitted into the end bell opening. Then install,
When the brush holder is fitted, the protrusions that are engaged with the brush opening pins and act in a direction in which they open each other, and release the engagement in the final fitting position, are provided with the end bell sidewalls. A brush device for a small motor, which is provided in. 2. The protrusion has a predetermined height sufficient to engage the tip of the brush opening pin, and
The width of the protrusion is substantially gradual so that the side surface of the protrusion abuts against the brush opening pin as the brush holder is inserted and opens the mutual opening until the contact with the brush opening pin is released at the final insertion position of the brush holder. The brush device for a small motor according to claim 1, wherein the brush device is formed wide. 3. The brush opening pin has a predetermined length that extends substantially parallel to the brush arm, and the tip of the brush opening pin is arranged so that at least the tip of the brush opening pin contacts the side surface of the protrusion. The brush device for a small motor according to claim 1, wherein the brush device has an L-shape that is bent toward the side wall of the end bell opening provided with the protrusion. 4. The small motor according to claim 1, wherein the brush opening pin is fixed by integral molding to a pedestal integrally molded with the brush holder so as to contact the brush arm at right angles to the extension direction of the brush arm. Brush device. 5. A hollow cylindrical metal case having a bottom to which a stator magnetic pole is attached, an end bell fitted so as to close an opening of the metal case, a bottom part of the metal case and the end bell. A rotor configured to integrally assemble a rotor magnetic pole and a commutator on a shaft rotatably supported by a bearing, and two brush arms having two brushes abutting on the commutator, respectively. In the method for manufacturing a brush device for a small motor including a brush holder, the brush holder supports two brush opening pins provided corresponding to the two brush arms, and the brush opening pins of the two brush arms are provided. Located on the inner side of each other, when a force acts in the direction of the corresponding brush arm side, it abuts the brush arm and the brush arm And a brush supported by the brush are opened to each other, the end bell is provided with an opening constituted by a side wall extending in a direction perpendicular to the rotor axial direction, and the end bell side wall is provided with the brush opening pin and While engaging and acting it in the direction of opening each other, a protrusion configured to release this engagement at the final fitting position is provided, and the rotor integrally assembled and configured in the metal case. After the insertion, the end bell is fitted so as to close the opening of the metal case, and then the brush holder is fitted and attached to the end bell opening. 6. The protrusion has a predetermined height sufficient to engage the tip of the brush opening pin, and
The width of the protrusion is substantially gradual so that the side surface of the protrusion abuts against the brush opening pin as the brush holder is inserted and opens the mutual opening until the contact with the brush opening pin is released at the final insertion position of the brush holder. The method for manufacturing a brush device for a small motor according to claim 5, wherein the brush device is formed wide. 7. The brush opening pin has a predetermined length extending substantially parallel to the brush arm, and at least the tip end of the brush opening pin contacts the side surface of the protrusion, The method of manufacturing a brush device for a small motor according to claim 5, wherein the brush device has an L-shape that is bent toward the side wall of the end bell opening provided with the protrusion. 8. The small motor according to claim 5, wherein the brush opening pin is fixed by integral molding to a pedestal integrally molded with the brush holder so as to contact the brush arm at right angles to the extension direction of the brush arm. Of manufacturing brush device of.