CN102810927A - electric motor - Google Patents

Abstract

The invention provides a four-pole motor. The motor includes a cylindrical motor base (1), a holder (2) on which a pair of brushes (23) are attached, and an end cover (3) covering one end of the motor base (1). The holder (2) has legs (21) extending radially in at least three directions, a hollow circular ring frame (22) supported by the legs (21), and a brush holder (24). The frame (24) supports a pair of brushes (23) at right angles to the annular frame (22). The end cover (3) has a plurality of flange pieces (32) fitted with the motor base (1), and a connector part (33) or a vent (34) is provided between the plurality of flange pieces (32). The motor base (1) is provided with holder fitting grooves (11) respectively fitted with the legs (21) of the holder (2) and a plurality of flange pieces (32) respectively fitted with the end cover (3) on one end thereof. ) a plurality of end cap fitting grooves (12) for fitting. According to this four-pole motor, even if the positioning accuracy of the brush holder is improved in this four-pole motor, it is possible to sufficiently cool the inside of the motor.

Description

electric motor

technical field

The present invention relates to a motor including a cylindrical motor base, a holder on which a pair of brushes are attached, and an end cover covering one end of the motor base. Wherein, four permanent magnets are oppositely arranged on the inner surface of the motor base.

Background technique

In the prior art, such motors include: a two-pole motor in which two permanent magnets are oppositely arranged on a cylindrical motor base, and a four-pole motor in which four permanent magnets are oppositely arranged. It is known that when a two-pole motor is compared with a four-pole motor, the four-pole motor is more prone to vibration and noise than the two-pole motor.

In order to prevent vibration and noise, as shown in the following Patent Document 1 (Japanese Patent Application Publication No. 4-502400) and Patent Document 2 (Japanese Utility Laid-Open Publication No. 6-44362), there is known a brush with an elastic member. A motor in which the holder is mounted to the motor base or endshield.

Here, in a four-pole motor, since it is necessary to improve the positioning accuracy of the brush holder relative to the permanent magnet of the motor base, as described in the above-mentioned Patent Document 1, it is desirable to directly connect the brush holder (without borrowing from the end cap) to the motor base.

However, when connecting the brush holder directly (without the end cover) to the motor base, it is necessary not only to provide the connection part of the end cover on the motor base, but also to provide the connection part of the brush holder on the motor base. As a result, there is a problem that the air vents capable of cooling the inside of the motor cannot be sufficiently ensured.

Contents of the invention

Therefore, the object of the present invention is to provide a four-pole motor. In this four-pole motor, even when the positioning accuracy of the brush holder is improved, it is possible to sufficiently cool the inside of the motor.

In order to achieve the above object, the motor of the first invention has a cylindrical motor base, a holder on which a pair of brushes are installed, and an end cover covering one end of the motor base. of permanent magnets, the motor is characterized in that,

The holder includes legs extending radially in at least three directions, a hollow circular ring frame supported by the legs, and a brush holder that holds the pair of brushes at right angles to each other. Supported on the ring frame,

The end cover has a plurality of flange pieces fitted to the motor base, and a connector part or a vent is provided between the plurality of flange pieces,

The motor base is provided with at least three holder fitting grooves respectively fitted to the legs of the holder and a plurality of end cover fittings respectively fitted to the plurality of flange pieces of the end cover on one end side thereof. Merge slot.

According to the motor of the first invention, since the holder is directly connected to the motor base through at least three legs, it is possible to satisfy the high positioning accuracy of the holder required in a four-pole motor.

Furthermore, by providing a plurality of flange pieces on the end cap, the flange pieces can be fitted into the end cap fitting grooves to fix the flange pieces. At the same time, a connector portion or a vent can be formed between the flange pieces. This ensures sufficient ventilation openings for cooling the inside of the motor

As described above, according to the motor of the first invention, in a four-pole motor, even when the positioning accuracy of the brush holder is improved, it is possible to sufficiently cool the inside of the motor.

The motor according to the second invention is characterized in that, in the first invention, the holder fitting groove and the end cover fitting groove of the motor base are formed in such a manner that the holder fitting groove is formed in the end cover fitting groove. on the fitting groove, so that the flange piece fitted to the fitting groove of the end cover covers the leg portion fitted to the fitting groove of the retainer.

According to the electric motor of the second invention, it is possible to ensure sufficient ventilation openings for cooling the inside of the electric motor. At the same time, by forming the holder fitting groove on the end cover fitting groove, the holder fitting groove and the end cover fitting groove can be simultaneously formed on one end side of the motor base. Furthermore, the leg portion of the holder fitted in the holder fitting groove can be prevented from coming out of the holder fitting groove by the flange piece fitted in the end cap fitting groove.

The motor according to the third invention is characterized in that, in the first or second invention, the leg portion of the holder is fitted into the holder fitting groove of the motor base via anti-vibration rubber.

According to the electric motor of the third invention, it is possible to ensure sufficient ventilation openings for cooling the inside of the electric motor. At the same time, vibration and noise reduction in the four-pole motor can be achieved by providing anti-vibration rubber on the legs of the holder that fit into the holder fitting grooves.

Description of drawings

FIG. 1 is an exploded view showing the structure of a motor.

FIG. 2 is a schematic view showing an assembled state of the motor of FIG. 1 .

Fig. 3 is an exploded view showing the configuration of a motor in another embodiment.

Symbol Description

1: Motor base; 2: Holder; 3: End cover; 11: Fitting groove of holder; 12: Fitting groove of end cover; 21: Leg; 21a: Anti-vibration rubber; 22: Ring frame; 23: Brush; 24: brush holder; 32: flange piece; 33: connector part; 34: air vent.

Detailed ways

Referring to FIG. 1, the structure of the electric motor of this embodiment is demonstrated.

The motor of this embodiment includes a motor base 1 , a holder 2 , and an end cover 3 .

The motor base 1 is a cylindrical member made of metal, and four permanent magnets 10 are provided facing each other on its inner surface. That is, the motor of this embodiment is a four-pole motor having four permanent magnets 10 .

The motor base 1 has a plurality of holder fitting grooves 11 for fixing the holder 2 and a plurality of end cover fitting grooves 12 for fixing the end cover 3 on one end thereof. Note that details of the holder fitting groove 11 and the end cap fitting groove 12 will be described later.

The other end of the motor base 1 is covered by a metal motor bracket 13, which constitutes a front bearing. In the motor bracket 13, a ventilation hole 13a composed of a plurality of through holes is formed.

The holder 2 is a holder made of synthetic resin, on which a pair of brushes 23 are mounted. The holder 2 includes legs 21 extending radially in three directions (120-degree intervals), and a hollow circular frame 22 supported by the legs 21 .

A pair of brush holders 24 are arranged on the annular frame 22 to support a pair of brushes 23 so that the pair of brushes 23 are at right angles. In addition, the brush 23 is urged inward in the circumferential direction by an urging mechanism not shown (for example, a coil spring). At the same time, the brush 23 is electrically connected to a connector described later by a braided wire.

Anti-vibration rubber 21a is attached to the tip of the leg portion 21 . A fitting groove 21c is formed on the rear end side of the anti-vibration rubber 21a, and a protruding portion 21b formed at the tip of the leg portion 21 is fitted into the fitting groove 21c. In addition, if necessary, an engaging portion or the like for preventing dropout may be formed on one or both of the protruding portion 21b and the fitting groove 21c. Further, a collar portion 21d that expands in diameter toward the outer periphery is formed on the rear end side of the anti-vibration rubber 21a.

The end cover 3 is a metal component used to cover one end of the motor base 1 . The end cover 3 includes a through hole 31 serving as a rear bearing and three flange pieces 32 fitted to the motor base 1 .

Three flange pieces 32 are formed on the outer peripheral portion of the end cap 3 at intervals of 120 degrees, like the legs 21 of the holder 2 . A connector portion 33 or a vent 34 is provided between adjacent flange pieces 32 . Moreover, the flange part 32 forms the collar part 32a which protrudes slightly to the outer side of a circumferential direction at the front-end|tip part.

More specifically, the connector portion 33 is connected to a portion where the notch 33 a is formed, and the vent 34 is formed between adjacent flange pieces 32 at a portion where the connector portion 33 is not connected. Cutouts 33 are formed on the outer peripheral edge of the end cap 3 between adjacent flange pieces 32 .

The connector part 33 has the convex part 33b which fits in the notch 33a, and the upper and lower side holding pieces 33c and 33d which pinch the convex part 33b. Thus, when the convex portion 33b is fitted into the notch 33a, the outer peripheral edge of the end cap 3 is held by the holding pieces 33c, 33d, whereby the connector portion 33 is fixed.

Next, the holder fitting groove 11 and the end cap fitting groove 12 formed in the motor base 1 which are pushed back from the description will be described.

The holder fitting grooves 11 are grooves in which the legs 21 of the holder 2 are respectively fitted. The holder fitting groove 11 is formed so that the anti-vibration rubber 21a of the leg portion 21 is fitted thereto.

The end cap fitting grooves 12 are grooves for respectively fitting the flange pieces 32 of the end cap 3 . The end cap fitting groove 12 is formed so that the flange part 32a of the flange piece 32 fits in this groove|channel especially.

Here, the holder fitting groove 11 and the end cap fitting groove 12 are formed in such a manner that the holder fitting groove 11 is formed at the bottom of the end cap fitting groove 12 so that the protrusion fitted into the end cap fitting groove 12 The edge piece 32 covers the leg portion 21 fitted in the holder fitting groove 11 .

Next, an assembled state of the motor will be described with reference to FIG. 2 . That is, the state where the holder 2 and the end cover 3 are attached to the motor 1 .

First, the three leg portions 21 of the holder 2 are respectively fitted into the three holder fitting grooves 11 of the motor base 1 via the anti-vibration rubber 21a. More specifically, at this time, the flange portion 21d of the anti-vibration rubber 21a is in contact with the inner surface of the motor base 1, and the tip portion of the anti-vibration rubber 21a is fitted into the fitting groove 11 of the holder.

Accordingly, since the holder 2 is directly connected to the motor base 1 through the three legs 21 , the high positioning accuracy of the holder 2 required in a four-pole motor can be satisfied. At the same time, vibration and noise at the four-pole motor can be reduced through the anti-vibration rubber 21a.

In addition, in this state, the bottom of each end cover fitting groove 12 of the motor base 1 and the leg part 21 fitted in the holder fitting groove 11 are horizontal. Furthermore, the three flange pieces 32 of the end cover 3 are fitted into the three end cover fitting grooves 12 of the motor base 1 .

Accordingly, the leg portion 21 of the holder fitted in the holder fitting groove 11 can be prevented from coming out of the holder fitting groove 11 by the flange piece 32 fitted in the end cap fitting groove 12 . At the same time, it is possible to securely form cooling vents on one end side of the motor base 1 on which the holder 2 and the end cover 3 are mounted.

That is, in this assembled state, the connector portion 33 or the vent 34 can be formed between adjacent flange pieces. At the same time, by forming the holder fitting groove 11 in the end cover fitting groove 12 , it is possible to avoid the problem of obstructing ventilation due to the leg portion 21 of the holder 2 being disposed between the flange pieces 32 .

In this way, according to the motor of the present embodiment, even when the positioning accuracy of the brush holder is improved by directly connecting the holder 2 to the motor base 1, it is possible to obtain the brush holder through the gap formed between the adjacent flange pieces 32. The air vent 34 fully cools the inside of the motor.

In this embodiment, the following configuration is described: the holder 2 has legs 21 extending in three directions (at intervals of 120 degrees), the motor base 1 has three holder fitting grooves 11, and the three Each leg portion 21 fits with three holder fitting grooves 11. At the same time, the end cover 3 has three flange pieces 32, and the motor base 1 has three end cover fitting grooves 12. These three flange pieces 32 and The three end cap fitting grooves 12 fit. However, the leg portion 21, the retainer fitting groove 11, the flange piece 32, and the end cap fitting groove 12 are not limited to three, and may be three or more. For example, it can be four, five, etc.

In addition, for example, as shown in the exploded view in FIG. 3 , the motor of the present invention can also be constructed in the following manner: the holder 2 has legs 21 extending radially in four directions (about 90 degree intervals), and the motor base 1 has four legs. There are four holder fitting grooves 11, and the four leg portions 21 fit into the four holder fitting grooves 11. Meanwhile, the end cover 3 has four flange pieces 32 , the motor base 1 has four end cover fitting grooves 12 , and the four flange pieces 32 are fitted with the four end cover fitting grooves 12 .

Claims (3)

1. A motor comprising a cylindrical motor base, a holder with a pair of brushes and an end cover covering one end of the motor base, four opposite permanent magnets are arranged on the inner side of the motor base , the motor is characterized in that, The holder includes legs extending radially in at least three directions, a hollow circular ring frame supported by the legs, and a brush holder that supports the pair of brushes at right angles. On the ring frame, The end cover has a plurality of flange pieces fitted to the motor base, and a connector part or a vent is provided between the plurality of flange pieces, The motor base is provided with at least three holder fitting grooves respectively fitted to the legs of the holder and a plurality of end cover fittings respectively fitted to the plurality of flange pieces of the end cover on one end side thereof. Merge slot. 2. The motor according to claim 1, wherein the retainer fitting groove and the end cap fitting groove of the motor base are formed in the following manner: the retainer fitting groove is formed in the end cap fitting groove. on the fitting groove, so that the flange piece fitted to the fitting groove of the end cover covers the leg portion fitted to the fitting groove of the retainer. 3. The electric motor according to claim 1 or 2, wherein the legs of the holder are fitted into the holder fitting grooves of the motor base via anti-vibration rubber.

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