KR100337745B1 - Brush Holder - Google Patents

Abstract

The present invention relates to a brush holder of an electric motor mounted on a rotary device such as an electric vacuum cleaner and an electric tool. The brush holder is integrally molded with synthetic resin to solve the problem of right angle deviation, thereby improving productivity and maintaining the brush. By designing the shape of the part to cool the brush, the temperature of the brush holder is also lowered to provide a broach holder having excellent brush sliding characteristics without causing thermal deformation, so that the brush is kept in the inserted state. The frame fixing part which fixes the brush holding part to the frame of the electric motor so that the holding part and the tip of the brush are in sliding contact with the commutator is integrally formed with a resin material. Is formed, and the airflow passes through the voids. It was set as.

By such a structure, the effect that the perpendicularity which arises at the time of production can be prevented can be improved, productivity can be improved, and the brush holder which is excellent in the sliding characteristic of a brush can be provided without a thermal deformation.

Description

Brush Holder {

The present invention relates to a brush holder of an electric motor mounted on a rotary device such as an electric vacuum cleaner and an electric tool.

In the related art, for example, as disclosed in Japanese Utility Model Laid-Open Publication No. 54-5709, since a brush that energizes with a commutator of an electric motor generates heat due to friction with a surface of a commutator rotating at high speed and sparks of current. The brush holder holding this brush is known to be used by fixing a metal frame with heat resistance to an insulating support in consideration of thermal deformation. 24 is an exploded perspective view of a conventional brush holder. Reference numeral 21 is a metal frame, and a caulking claw 23 for fixing to an insulating support 22 is formed on the upper portion thereof. On the other hand, the caulking hole 24 suitable for this caulking claw 23 is also formed in the insulating support part 22. As shown in FIG. Moreover, when the metal frame 21 is inserted into the inner wall 25 of the insulating support part 22, this metal frame 21 is fixed to the locking end part 26 provided in the inner wall 25. As shown in FIG. At this time, the caulking claw 23 is bent and the caulking hole 24 is caulked to fix the metal frame 21 and the insulating support portion 22. Here, the caulking hole 24 and the locking end 26 of this insulating support part 22 are formed in substantially the same height.

Since it has the said structure, even if the brush and the insulating support part 22 do not directly contact, and even if the insulating support part 22 becomes high temperature and generate | occur | produces thermal deformation, the metal frame 21 and the insulating support part 22 are fixed. The position is about the same height, and research has been conducted that does not cause displacement due to thermal deformation and does not adversely affect the sliding characteristics of the brush.

However, since the conventional brush holder is composed of two parts of the metal frame and the insulating support part, any deviation occurs in the squareness of the metal frame and the insulating support part due to the nonuniformity of the manufacturing process, so that the power supply of the commutator motor is performed. It was adversely affecting the sliding of the brush and commutator. Particularly, when the tip portion of the brush contacting the commutator is formed in a shape that follows the R shape of the commutator in order to improve rectification, commutation defects are likely to occur if there is a slight surface contact misalignment at a right angle. There existed a problem that the lifetime of a brush fell by lack and spark (spark) defect. On the other hand, when the brush holder is integrally molded with synthetic resin without providing a metal frame, there is a problem in that the temperature of the holder portion in contact with the brush may be high to cause thermal deformation.

An object of the present invention is to solve the above-mentioned problems, by forming the brush holder integrally with a synthetic resin or the like to solve the problem of the deviation of the right angle to improve the productivity, devise the shape of the part holding the brush By cooling the brush, the temperature of the brush holder is also lowered to provide a broach holder having excellent brush sliding characteristics without causing thermal deformation.

1 is a cross-sectional view showing a configuration of an electric motor showing the configuration of Embodiment 1 of the present invention;

2 is a top view of the brush holder of the electric motor showing the configuration of Embodiment 1 of the present invention;

3 is a side view of the brush holder of the electric motor showing the configuration of Embodiment 1 of the present invention;

4 is a cross-sectional view of the brush holder with the carbon brush showing the configuration of Example 1 of the present invention (a view taken along line III-III of FIG. 3),

5 is a cross-sectional view of the brush holder in which the carbon brush is inserted showing the configuration of Example 1 of the present invention (a view taken along line III-III of FIG. 3),

6 is a cross-sectional view of the brush holder in which the carbon brush is inserted showing the configuration of Example 1 of the present invention (a view taken along line III-III of FIG. 3),

7 is a cross-sectional view of the brush holder with the carbon brush showing the configuration of Example 1 of the present invention (a view taken along line II-II of FIG. 2),

8 is a rear view of the brush holder inserted with the carbon brush showing the configuration of Example 1 of the present invention;

9 is a temperature distribution diagram of a brush holding unit with and without a gap between the carbon brush and the brush holding unit;

FIG. 10 is a cross-sectional view of the brush holder with the carbon brush showing the configuration of Example 1 of the present invention (a view taken along line III-III of FIG. 3),

FIG. 11 is a cross-sectional view of the brush holder in which the carbon brush is inserted (the view taken along the line III-III of FIG. 3) showing the configuration of Embodiment 2 of the present invention;

12 is a cross-sectional view of a brush holder in which a carbon brush is inserted (a view taken along line III-III of FIG. 3) showing the configuration of Embodiment 2 of the present invention;

FIG. 13 is a cross-sectional view of the brush holder in which the carbon brush is inserted (the view taken along line III-III of FIG. 3) showing the configuration of Embodiment 2 of the present invention;

14 is a top view of the brush holder of the electric motor showing the construction of Embodiment 3 of the present invention;

Fig. 15 is a side view of the brush holder of the electric motor showing the construction of Embodiment 3 of the present invention;

FIG. 16 is a cross-sectional view of a brush holder in which a carbon brush is inserted (a view taken along line III-III of FIG. 15) showing the configuration of Embodiment 3 of the present invention;

FIG. 17 is a cross-sectional view of the brush holder with the carbon brush showing the configuration of Example 3 of the present invention (a view taken along line III-III of FIG. 15),

FIG. 18 is a cross-sectional view of the brush holder with the carbon brush showing the configuration of Example 3 of the present invention (a view taken along line III-III of FIG. 15);

Fig. 19 is a side view of the brush holder of the electric motor showing the construction of Embodiment 4 of the present invention;

20 is a side view of the brush holder of the electric motor showing the construction of Embodiment 4 of the present invention;

FIG. 21 is a cross-sectional view of the brush holder with the carbon brush showing the configuration of Example 4 of the present invention (a view taken along line III-III of FIG. 20);

Fig. 22 is a sectional view of the brush holder with the carbon brush showing the construction of the fourth embodiment of the present invention (a view taken along line III-III of Fig. 20),

FIG. 23 is a cross-sectional view of a brush holder in which a carbon brush is inserted (a view taken along line III-III of FIG. 20) showing the configuration of Embodiment 4 of the present invention;

24 is an exploded perspective view of a conventional brush holder.

※ Explanation of symbols about main part of drawing ※

1: frame of electric motor, 2: rotor, 3: stator, 4: commutator, 5: carbon brush, 6: brush holder, 7: brush holder, 8; Frame fixing, 9; Brush holder inner wall, 9a; Fixing part 9b; Recess, 9c; Arc, 9d; Uneven groove, 9e: corrugated groove, 9f: triangular groove, 10: slit, 11: inlet, 21: metal frame, 22: insulating support, 23: caulking claw, 24: caulking hole, 25: inner wall of brush holder, 26 ; Hanging end.

The present invention is integrally formed with a resin material of the cylindrical brush holding portion for holding the brush in the inserted state and the frame fixing portion for fixing the brush holding portion to the frame of the motor so that the tip of the brush is in sliding contact with the commutator, A gap penetrated in the longitudinal direction of the brush holding portion is formed between the inner wall of the brush holding portion and the brush, and air flows through the space.

In addition, the present invention is integrally formed with a resin material of the cylindrical brush holding portion for holding the brush in the inserted state and the frame fixing portion for fixing the brush holding portion to the frame of the motor so that the tip of the brush is in sliding contact with the commutator. In addition, a gap penetrated in the longitudinal direction of the brush holding portion is formed between the brush holding portion inner wall and the brush, and one end of the commutator side of the brush holding portion is provided with a ventilation slit communicating with the void.

In addition, the present invention is integrally formed with a resin material of the cylindrical brush holding portion for holding the brush in the inserted state and the frame fixing portion for fixing the brush holding portion to the frame of the motor so that the tip of the brush is in sliding contact with the commutator. In addition, a gap penetrated in the longitudinal direction of the brush holding portion is formed between the inner wall of the brush holding portion and the brush, and a ventilation hole communicating with the gap is formed on the side of the brush holding portion.

EXAMPLE

Example 1

1 is a cross-sectional view of a motor according to a first embodiment of the present invention, FIG. 2 is a top view of a carbon brush and a brush holder of the motor, and FIG. 3 is a side view of a carbon brush and a brush holder of the motor.

1 to 3, reference numeral 1 denotes an outer frame of the electric motor, in which a rotor 2, a stator 3, and a commutator 4 are provided in the frame 1 of the electric motor. Reference numeral 5 denotes a carbon brush having a substantially rectangular pillar. The tip is formed in an R shape so as to be in contact with the surface of the commutator 4 which rotates at high speed and to conduct electricity to the commutator 4. (6) is a brush holder holding the carbon brush (5), which is provided on the left and right of the commutator (4). The brush holder 6 is composed of a brush holding portion 7 having an insertion opening for inserting a carbon brush therein and a frame fixing portion 8 for holding and fixing the brush holding portion 7 to the frame 1. . Both the brush holding part 7 and the frame fixing part 8 are integrally molded with a thermosetting resin, for example, a phenol resin.

4 is a cross-sectional view taken along line III-III of the brush holder shown in FIG. 3. Here, (9) is an inner wall which directly holds the carbon brush of the brush holding part 7. The inserts have a shape of a support 9a for supporting the four corners of the carbon brush 5, a recess 9b for forming a gap between the carbon brush 5 and the brush holding portion 7, and an arc 9c. ) Is formed. Therefore, when the carbon brush 5 of a substantially rectangular pillar is inserted into this brush holding part inner wall 9, the space | gap of the recessed part 9b or the circular arc part 9c will generate | occur | produce in the side surface of the carbon brush 5, respectively.

This gap is not limited to the combination of the concave shape and the arc shape as shown in FIG. 4, and may be other than the combination of the arc shape, the combination of the concave shapes as shown in FIGS. 5 and 6. The larger the distance between the recess 9b and the carbon brush 5 and the distance between the top of the arc 9c and the carbon brush 5, the greater the cooling effect. It is preferable to set between 5 (mm) and 5 (mm).

In addition, as shown in FIG. 7, the recessed part 9b and the arc part 9c which form a space | gap pass through the longitudinal direction of the brush holder 6, and an airflow flows. That is, wind flows out from the hole formed by the recessed part 9b and the arc part 9c which were shown in the figure (FIG. 8) which looked at the brush holder 6 in the C direction of FIG.

Here, the thermal time strength (bending strength) of the resin material for forming the brush holder 6 will be described below. PPS (containing 40% glass), PET (containing 45% glass), PBT (containing 30% glass) of thermoplastic resins has a bending sensitivity of 200 to 250 (Mpa) at room temperature and a bending modulus of 10000 to 14000 (Mpa). At 250 ° C, the bending strength is 0 (Mpa) and the bending modulus decreases to 2000 (Mpa). On the other hand, thermosetting phenolic resin has a bending strength of 180 to 190 (Mpa) and a bending elastic modulus of 18000 (Mpa) at room temperature, but at 250 ° C., the bending strength is 100 (Mpa) and the bending elastic modulus of 12000 to 14000 (Mpa) is maintained. Doing.

Moreover, also in the dimension change in high temperature area | region (200 degreeC), in the case of a thermoplastic resin, -0. 2%--0. 6%, but in the case of thermosetting phenolic resin -0. -0 at 1%, 1000 hours. It is stable at 2% and shows the same tendency with respect to warping. Therefore, it is preferable to use thermoplastic phenol resin for the brush holder 6.

Next, the operation of the brush holder in Embodiment 1 configured as described above will be described. For example, when used in an electric vacuum cleaner motor, since the electric power is supplied to the commutator 4 via the carbon brush 5 by starting the electric motor, the temperature of the carbon brush 5 rises due to friction or the like. In particular, when an arc occurs at the tip of the carbon brush 5, the temperature may further rise to exceed 200 ° C. However, in this embodiment, since the gap is provided in the brush holding part 7 with the carbon brush 5, the carbon brush 5 and the brush holding part 7 can be cooled.

That is, in the gap between the recess 9b and the arc 9c formed on the inner wall 9 of the brush holding part 9, the wind drawn by the blower passes through the air vent of the frame 1 along the arrow direction in A in FIG. In this direction, the blower discharge wind enters the gap between the carbon brush 5 and the brush holding portion 7 and has a function of cooling the carbon brush 5. In addition, since the heat resistance of the carbon brush 5 can be reduced by this cooling action, the resistance loss is also reduced.

9 is a temperature distribution diagram of the carbon brush 5 in the case where a void is provided or not. In FIG. 9, the vertical axis | shaft is temperature (degreeC) and the horizontal axis | shaft is the air volume of the blower at the time of arrange | positioning the brush holder of this invention to an electric blower. Here, ○ represents the temperature distribution of the metal frame of the conventional brush holder. On the other hand,? And? Are the molded parts of the brush holder 6 integrally with a phenolic resin, where? Is the temperature distribution of the brush holding part 7 when no void is provided, and? Is the present embodiment in which the void is provided. The temperature distribution of the brush holding | maintenance part 7 concerning this. Thereby, it turns out that the temperature of the brush holding | maintenance part 7 falls about 10 degreeC by the cooling effect by providing the space | gap.

Moreover, since this brush holding part 7 is molded with a thermosetting phenolic resin, it can maintain sufficient strength also in bending strength and bending elastic modulus, and it is 500-600 hours also in the dimensional change in high temperature area | region (200 degreeC). In -0. -0 at 1%, 1000 hours. 2%. Also, even in the case where there is such a dimensional change, the position between the brush holding portion 7 and the frame fixing portion 8 is because the brush holding portion 7 and the frame fixing portion 8 are integrally molded. The shift does not occur, so that the sliding characteristics of the commutator 4 and the carbon brush 5 are not affected.

In this embodiment, the cooling voids are provided to face the four side surfaces of the carbon brush 5 having a substantially rectangular cross section. However, the present invention is not limited thereto, but the strength and carbon brush of the brush holding portion 7 are not limited thereto. In view of the holding force of (5) and the like, a gap may be provided to face two side surfaces of the carbon brush 5 as shown in FIG.

In addition, in this embodiment, since the wind flows in the direction B of the frame 1 along the direction of the arrow in A in Fig. 1, the warm discharge wind agitated by the blower causes the carbon brush 5 and the brush holding part ( 7) Although it is made to flow in the space | gap between them, this invention is not limited to this, You may provide special blowing means, etc., and let wind flow in B direction in FIG. In this case, since air (natural wind) that is cooler than the blower discharge wind flows into the gap between the carbon brush 5 and the brush holding portion 7, the carbon brush 5 and the brush holding portion 7 can be cooled further. .

Example 2

11 to 13 are cross-sectional views taken along line III-III of the brush holder shown in FIG. 11 to 13, 9d is an uneven groove, 9e is a wavy groove, and 9f is a triangular groove. Therefore, since the contact surfaces between the brush holding portion 7 and the carbon brush 5 are larger than those described in Example 1, the effect of cooling the carbon brush 5 is reduced, but the holding of the carbon brush 5 is more sure. It can be done. Accordingly, the shape of the voids formed in the brush holder 6 may be changed into a groove shape in consideration of the balance between the holding performance of the carbon brush 5 and the cooling action depending on the use of the electric motor on which the brush holder 6 is disposed.

Example 3

Fig. 14 is a top view of the carbon brush and the brush holder of the electric motor, Fig. 15 is a side view of the carbon brush and the brush holder of the electric motor, and Figs. 16 to 18 are sectional views taken along line III-III of the brush holder shown in Fig. 15. to be. 14-18, the same code | symbol as Example 1 shows the same or an equivalent part.

In FIG. 14 and FIG. 15, (10) is a slit formed to the side of the brush holding part 7 toward the longitudinal direction, and is provided in two or four places of the side of the brush holding part 7, and the dimension is a brush In order to maintain the intensity | strength of the holding | maintenance part 7 more than a fixed level, it is set within 20% of the length dimension of the brush holding part 7, and within 50% of the width dimension.

In this embodiment, the blower discharge wind is introduced into the brush holding portion 7 (in the direction of the arrows in FIGS. 14 and 15) from the slit 10 and passes through the pores 9b and 9c in the brush holding portion 7. You can. Therefore, the blower discharge wind can be brought into direct contact with the carbon brush 5, and the blower discharge wind can be further flowed into the carbon brush 5 by increasing the inlet opening area of the blower discharge wind. Cooling effect can be further enhanced, and the temperature of the brush holding part 7 of the brush holder 6 can be further reduced.

Moreover, since this slit 10 is formed so that it may communicate with the space | gap of the inner wall 9 of the brush holding part, it does not affect the support and fixation of the carbon brush 5, and it does not affect the commutator 4 and the carbon brush 5. Does not adversely affect the sliding characteristics.

Example 4

Fig. 19 is a top view of the carbon brush and the brush holder of the electric motor, Fig. 20 is a side view of the carbon brush and the brush holder of the electric motor, and Figs. 21 to 23 are sectional views taken along line III-III of the brush holder shown in Fig. 20. to be. 19-23, the same code | symbol as Example 1 shows the same or an equivalent part.

In Fig. 19 and Fig. 20, reference numeral 11 denotes an inlet for introducing a blower discharge wind, and penetrates through the inner wall of the brush holding portion 9. As shown in Figs. 21 to 23, these inlets are formed corresponding to the gaps between the two or four brush holder inner walls 9, respectively. In addition, since the hole area is 5% or more of the area of the brush holding portion 7, the blower discharge wind can be sufficiently introduced.

In the third embodiment, the blower discharge wind is introduced into the brush holding unit 7 from the slit 10, but in this embodiment, a hole is formed in the side and the upper and lower surfaces of the brush holding unit 7 instead of the slit 10, It is to introduce blower discharge wind.

As is clear from the above invention, the brush holder according to the present invention is a frame for holding a brush in the cylindrical state holding the brush and the brush holding portion fixed to the frame of the motor so that the front end of the brush sliding contact with the commutator The fixing portion is integrally molded with a resin material, and a gap penetrated in the longitudinal direction of the brush holding portion is formed between the inner wall of the brush holding portion and the brush, and air flows through the space. As a result, it is possible to provide a brush holder which is excellent in sliding characteristics of the brush without causing thermal deformation, thereby improving productivity by preventing misalignment caused during production.

In addition, the brush holder according to the present invention comprises a cylindrical brush holding portion for holding the brush in the inserted state and a frame fixing portion for fixing the brush holding portion to the frame of the motor so that the tip of the brush is in sliding contact with the commutator. It is formed integrally with the furnace, and a gap penetrated in the longitudinal direction of the brush holding portion is formed between the inner wall of the brush holding portion and the brush, and one end of the commutator side of the brush holding portion is provided with a ventilation slit communicating with the void. As a result, it is possible to provide a brush holder which is excellent in sliding characteristics of the brush without causing thermal deformation, thereby improving productivity by preventing misalignment caused during production.

In addition, the brush holder according to the present invention comprises a cylindrical brush holding portion for holding the brush in the inserted state and a frame fixing portion for fixing the brush holding portion to the frame of the motor so that the tip of the brush is in sliding contact with the commutator. It is formed integrally with the furnace, and the air gap penetrating in the longitudinal direction of the brush holding portion is formed between the inner wall of the brush holding portion and the brush, and the ventilation hole communicating with the air gap is formed on the side of the brush holding portion. As a result, it is possible to provide a brush holder which is excellent in sliding characteristics of the brush without causing thermal deformation, thereby improving productivity by preventing misalignment caused during production.

Claims (3)

A cylindrical brush holding portion for holding the brush in the inserted state and a frame fixing portion for fixing the brush holding portion to the frame of the motor so that the tip of the brush is in sliding contact with the commutator are integrally formed of a resin material, and the brush holding The brush holder which is formed between the inner wall of the part and the brush in the longitudinal direction of the brush holding portion, the air flow passes through the gap. A cylindrical brush holding portion for holding the brush in the inserted state and a frame fixing portion for fixing the brush holding portion to the frame of the motor so that the tip of the brush is in sliding contact with the commutator are integrally formed of a resin material, and the brush holding A brush holder is formed between the inner wall of the part and the brush, the air gap penetrating in the longitudinal direction of the brush holding portion, and one end of the commutator side of the brush holding portion is provided with a ventilation slit communicating with the air gap. A cylindrical brush holding portion for holding the brush in the inserted state and a frame fixing portion for fixing the brush holding portion to the frame of the motor so that the tip of the brush is in sliding contact with the commutator are integrally formed of a resin material, and the brush holding A brush holder characterized in that a gap penetrated in the longitudinal direction of the brush holding portion is formed between the inner wall of the portion and the brush, and a ventilation hole communicating with the void is formed on the side of the brush holding portion.