JP3038544U - Small DC motor - Google Patents

Abstract

(57) [Summary] [PROBLEMS] The present invention aims to improve the performance of a small DC motor, and particularly to extend its service life. An end cap in a small direct current motor includes a ring-shaped fitting portion and a pair of bearing support members that support the bearing portion, and the end cap is provided between the ring-shaped fitting portion and the bearing portion. And a plurality of protrusions and wall grooves are formed in the bearing wall and the facing wall of the ring-shaped fitting portion facing the bearing portion of the ring-shaped fitting portion. The terminals connected to the brush are integrally disposed on a pair of brush mounting members that are engaged and held by the plurality of protrusions and the wall grooves, and the pair of brush mounting members are formed of a metal plate having a spring property. , A brush supporting portion for inserting a brush into the brush insertion space, and an obtuse angle rising from the brush supporting portion and abutting against the opposing wall of the ring-shaped fitting portion while urging the spring. A pair of brush mounting members having brushes can be attached and detached by engaging and disengaging the leaf spring portion with the plurality of protrusions.

Description

[Detailed description of the invention]

[0001]

[Industrial applications]

 The present invention relates to a small direct current motor, and more particularly to a small direct current motor in which a brush can be attached and detached, that is, a brush can be replaced, and a long life of the motor can be realized.

[0002]

[Prior art]

 As is well known, various motors are used for consumer and industrial use, and various shapes and sizes are used according to their applications. Among them, especially small DC motors are It has a wide range of applications and is widely used in various fields.

In general, the small DC motor has a cylindrical casing having an open end on one side and a closed end face on the other side, and a magnet inside thereof, and a casing arranged inside the casing. A rotor having a rotating shaft and an end cap fitted to the opening end of the casing, and a coil to which current is supplied from a commutator arranged around the rotating shaft is arranged in the rotor. The end cap is equipped with a pair of brushes for supplying an electric current to the coil of the rotor arranged in the casing through a commutator and a terminal connected to the brush.

Then, the rotating shaft of the rotor is supported by the bearing portion formed on the closed end surface of the casing and the end cap, and a magnet is arranged in the casing to attach the brush and the brush mounted on the end cap. The rotor is rotated by supplying a current from a connecting terminal to a coil arranged in the rotor through a commutator, and the rotation of the rotor is used as a driving force.

By the way, due to the rotation of the rotor, the brush contacting the rectifier arranged around the rotation axis of the rotor gradually wears. When the brush wears and reaches the end of its life, It is necessary to replace the brush, and with a large DC motor, which has a relatively large brush itself, the brush can be replaced and used for a long period of time.

However, the brush of a small DC motor is very small, and in most cases, it is formed integrally with the end cap that fits in the casing, and the brush is fixed to the end cap. Therefore, to replace the brush, you have to remove the end cap from the casing, and it is not easy to replace the brush.Therefore, when the brush wears and reaches the end of its life, the small DC motor itself must be removed. In the case of a small DC motor, the brush life will be the life of the small DC motor when used under normal usage conditions, in order to extend the life of the small DC motor. It was necessary to improve the wear resistance of the material forming the brush.

[0007]

[Problems to be solved by the device]

 According to the above-mentioned conventional technology, in order to realize a long life of a small DC motor, it is considered to use a material having excellent wear resistance as a material for forming the brush. Even if a brush is made of a material that excels in durability, the life of the brush is not dramatically improved, and the length of a small DC motor that is worth the cost of forming the brush with a material with excellent wear resistance The reality is that the life has not been shortened, and no technology has been proposed to replace the brush in a small DC motor.

[0008]

[Purpose of the invention]

 Therefore, the object of the present invention is to solve the problems of the conventional technology as described above, and it is possible to replace the brush, which determines the longevity of the small DC motor, and to replace the brush of the small DC motor. It is to provide a small DC motor with a replaceable brush that can achieve a longer life.

[0009]

Means for Solving the Problems In order to achieve the above object, the present invention has the following technical means. That is, to explain with reference to the reference numerals used in the accompanying drawings corresponding to the embodiments, a cylindrical casing having an open end 11 on one side and a closed end face 12 on the other side, in which a magnet is arranged. 1 and a rotor having a rotating shaft 31 arranged in the casing 1, and an end cap 2 fitted into the open end 11 of the casing 1. The rotor is arranged around the rotating shaft 31. A coil to which current is supplied from the commutator is disposed, and the end cap 2 is provided with a pair of brushes for supplying current to the coil of the rotor disposed in the casing 1 through the commutator. 4 and a terminal 5 connected to the brush 4 are mounted to support the rotary shaft 31 of the rotor by the bearing of the closed end face 12 of the casing 1 and the bearing of the bearing portion 8 formed on the end cap 2 and at the same time. A magnet is arranged in the housing 1, and a current is supplied from a pair of brushes 4 mounted on the end cap 2 and a terminal 5 connected to the brush 4 to a coil arranged on the rotor through a commutator. In a small direct current motor that rotates a rotor by means of a rotary shaft 31 of the rotor to obtain driving force, the end cap 2 has a ring-shaped fitting portion 6 that fits into an open end 11 of a casing 1, and It is composed of a pair of bearing support members 7 that stand up in a pair from the ring-shaped fitting portion 6 with the rotary shaft 31 of the rotor interposed therebetween, and a bearing portion 8 supported by the pair of bearing support members 7. A brush insertion space S is formed between the fitting portion 6 and the bearing portion 8, and the facing wall 18 facing the bearing portion 8 of the ring-shaped fitting portion 6 is perpendicular to the rotating shaft 31 of the rotor. In shape A pair of bearing support members 7 that are provided with a plurality of protrusions 22 on the periphery thereof and rise from the ring-shaped fitting portion 6 are parallel to the rotating shaft 31 of the rotor and that have the ring shape. Has a side wall 19 perpendicular to the facing wall 18 of the fitting portion 6, and the bearing portion 8 has a side wall 20 which is flush with the side wall 19 of the pair of bearing support members 7 and an inclination inclined toward the side wall 20. The pair of brushes 4 mounted on the end cap 2 and the terminals 5 connected to the brushes 4 have a wall groove 23 formed by the surface 21 and the wall 5 opposite to the ring-shaped fitting portion 6 facing wall. It is formed integrally with a pair of brush mounting members 3a, 3b which are engaged and held by a plurality of protrusions 22 formed on the peripheral edge of 17 and a wall groove 23 formed in the bearing 8. The pair of brush mounting members 3a, 3b , The brush 4 and the terminal 5 connected to the brush 4 are formed of a metal plate having a spring property and come into contact with the side wall 19 of the pair of bearing members 7 and the side wall 20 of the wall groove 23 of the bearing portion 8. Together, the brush support portion 9 in which the brush support piece 26 for inserting the brush 4 into the brush insertion space S is formed, and the brush support portion 9 rises at an obtuse angle and is provided on the opposing wall 17 of the ring-shaped fitting portion 6. A pair of brush mounting members 3a having a brush 4 is formed by a leaf spring portion 10 that abuts while being biased by a spring, and by engaging and disengaging the leaf spring portion 10 and the plurality of protrusions 22. , 3b can be attached and detached, which is a small DC motor.

[0010]

[Action]

 The present invention comprises the above-mentioned technical means, and the ring-shaped fitting portion 6 in which the end cap 2 fitted in the casing 1 of the small direct current motor is fitted in the opening end 11 of the casing 1, and the ring-shaped fitting. The ring-shaped fitting portion includes a pair of bearing support members 7 rising from the portion 6 with the rotary shaft 31 of the rotor sandwiched therebetween, and a bearing portion 8 supported by the pair of bearing support members 7. A brush insertion space S is formed between the bearing 6 and the bearing portion 8, and a pair of brush mounting members 3a and 3b integrally formed with the brush 4 and a terminal 5 connected to the brush 4 are provided as a pair of bearings. The support members 7 are paired so as to be sandwiched therebetween and are detachably attached to the end caps 2. However, the brush attachment members 3a and 3b are attached to the end caps 2 only by the brush attachment members 3a, 3b This can be performed only by engaging the brush support portion 9 and the leaf spring portion 10 with the wall groove 23 and the plurality of protrusions 22 of the end cap 2, and the mounting can be performed very easily. By disengaging the brush supporting portion 9 and the leaf spring portion 10 of the brush mounting members 3a and 3b from the wall groove 23 and the plurality of protrusions 22 of the end cap 2, the brush mounting members 3a and 3b can be easily terminated. It can be removed from the cap 2.

[0011]

【Example】

 Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. First, a general small DC motor has a cylindrical casing 1 having an open end 11 on one side and a closed end face 12 on the other side, and a magnet (not shown) arranged therein, and the above casing. The rotor includes a rotor (not shown) having a rotating shaft 31 disposed inside the casing 1, and an end cap 2 fitted into the open end 11 of the casing 1. The rotor is arranged around the rotating shaft 31. A coil (not shown) to which a current is supplied from a commutator (not shown) is arranged, and the end cap 2 is connected to the coil of the rotor arranged in the casing 1 via the commutator. A pair of brushes 4 for supplying an electric current and a terminal 5 connected to the brushes 4 are mounted, and the rotary shaft 31 of the rotor is formed on a bearing (not shown) of the closed end face 12 of the casing 1 and the end cap 1. Bearing part 8 In addition to being supported by a receiver (not shown), a magnet is arranged in the casing 1, and a pair of brushes 4 mounted on the end cap 2 and terminals 5 connected to the brushes 4 are arranged on the rotor. By supplying an electric current to the coil via a commutator, the rotor is rotated and a driving force is obtained from the rotating shaft 31 of the rotor.

The small DC motor of the present invention, as shown in FIGS. 1 to 6, is fitted to the open end 11 of the casing 1 instead of the end cap of the conventional general small DC motor. Supported by the pair of bearing support members 7 and the pair of bearing support members 7 that stand up in a pair from the ring-shaped fit portion 6 with the rotary shaft 31 of the rotor interposed therebetween. The end cap 2 is composed of a bearing portion 8 and a brush insertion space S 1 is formed between the ring-shaped fitting portion 6 and the bearing portion 8. Is detachably mounted in a pair so that a pair of brush mounting members 3a and 3b integrally formed with a brush 4 and a terminal 5 connected to the brush 4 sandwich a pair of bearing support members 7. With things is there.

The end cap 2 of the present invention will be described in more detail. As shown in FIGS. 7, 8 and 9, the end cap 2 faces the bearing portion 8 of the ring-shaped fitting portion 6 that constitutes the end cap 2. The facing wall 18 is formed perpendicularly to the rotating shaft 31 of the rotor, and has a plurality of protrusions 22 on the periphery thereof.

A pair of bearing support members 7 that stand up in a pair with the rotary shaft 31 of the rotor sandwiched from the ring-shaped fitting portion 6 are parallel to the rotary shaft 31 of the rotor and have the ring shape. Has a side wall 19 perpendicular to the facing wall 18 of the fitting portion 6, and each of the pair of bearing support members 7 is formed by a plurality of bearing support pieces 25 arranged in a lattice pattern. It improves the air permeability inside and outside the end cap 2 and inside and outside the motor.

A bearing (not shown) for supporting the rotating shaft 31 of the rotor is arranged in the bearing portion 8 and is flush with the side walls 19 of the pair of bearing supporting members 7. A wall groove 23 composed of the side wall 20 and an inclined surface 21 inclined toward the side wall 20 is formed. At the center of the wall groove 23, a pair of brush mounting members 3 a mounted on the end cap 2 are provided. Positioning protrusions 24 for positioning 3b are formed.

Next, the pair of brush mounting members 3a and 3b mounted on the end cap 2 will be described in detail. As shown in FIGS. 10, 11 and 12, the pair of brush mounting members 3a and 3b are installed. Are integrally formed with the brush 4 and the terminal 5 connected to the brush 4, and are formed on the peripheral edge of the opposing wall 18 of the ring-shaped fitting portion 6 constituting the end cap 2. The protrusion 22 and the wall groove 23 formed in the bearing 8 are engaged and held.

The pair of brush mounting members 3 a, 3 b are made of a metal plate having a spring property and provided with a brush 4 and a terminal 5 connected to the brush 4, and the side wall 19 and the bearing portion of the pair of bearing support members 7 are provided. 8, a brush supporting portion 9 which is in contact with the side wall 20 of the wall groove 23 of the No. 8 and which is formed with a brush supporting piece 26 for inserting the brush 4 into the brush insertion space S and a terminal piece 27 constituting the terminal 5, and the brush supporting portion. 9 is an obtuse angle, and is composed of a leaf spring portion 10 that abuts against the opposing wall 18 of the ring-shaped fitting portion 6 while biasing the spring, and the brush support portion 9 includes the bearing portion 8 A notch 29 that engages with a positioning protrusion 24 formed in the center of the wall groove 23 is formed, and the leaf spring portion 10 is formed in the opposing wall 18 of the ring-shaped fitting portion 6. Success A cutout portion 30 that engages with the plurality of formed protrusions 22 is formed.

Next, the attachment / detachment of the pair of brush mounting members 3a and 3b will be described. Here, the description will be given based on the brush mounting member 3a on the left side in FIG. 3 among the pair of brush mounting members 3a and 3b. First, when the brush mounting member 3a is mounted on the end cap 2 of the small DC motor, the brush supporting piece 26 formed on the brush supporting portion 9 of the brush mounting member 3a and the brush 4 are placed in the brush insertion space S of the end cap 2. After inserting the brush supporting portion 9 into the wall groove 23 of the bearing portion 8, the notch portion 29 of the brush supporting portion 9 and the positioning protrusion 24 of the wall groove 23 are engaged. Let

Next, with the end portion 28 of the brush support portion 9 engaged with the wall groove 23 of the bearing portion 8, the entire brush mounting member 3 a is tilted toward the end cap 2 side to form a pair of end caps 2. The brush support portion 9 is brought into contact with the side wall 19 of the bearing support member 7 and the side wall 20 of the wall groove 23 of the bearing portion 8, and the brush 4 supported by the brush support piece 26 is positioned in the brush insertion space S. A leaf spring portion 10 that elastically abuts against a child (not shown) and rises from the brush support portion 9 at an obtuse angle is provided on the opposing wall 18 of the ring-shaped fitting portion 6 that constitutes the end cap 2. The brush mounting member 3a is abutted while being urged by the spring, and the cutout portion 30 formed in the leaf spring portion 10 is engaged with the plurality of protrusions 22 formed in the facing wall 18. The mounting on the end cap 2 is completed.

The brush mounting member 3a is mounted on the end cap 2 by attaching the brush supporting portion 9 and the leaf spring portion 10 of the brush mounting member 3a to the wall groove 23 and the plurality of protrusions 22 formed on the end cap 2. Can be carried out only by engaging the brush supporting member 9 and the plate spring portion 10 of the brush mounting member 3a with the wall groove 23 of the end cap 2 and the plurality of protrusions 22. Since the leaf spring portion 10 of the brush mounting member 3a works in a state in which the spring is biased, there is no fear that the brush mounting member 3a mounted on the end cap 2 will accidentally fall off. is there.

Furthermore, when removing the brush mounting member 3a from the end cap 2, it can be easily performed by a procedure reverse to the above-described mounting procedure. Since no tools are required, the brush mounting member 3a having the brush 4 can be replaced very easily, the life of the small DC motor can be extended, and the brush 4 can be easily attached / detached (replaced). As a result, it becomes easier to assemble a small DC motor, and at the same time, the brush 4 can be replaced according to the purpose of the small DC motor and the required performance. Is obtained.

The protrusions 22 formed on the ring-shaped fitting portion 6 described in the above embodiment, the wall groove 23 of the bearing portion 8, the pair of brush mounting members 3 a and 3 b are the bearing support members 7. The brush mounting members shown in FIGS. 10, 11 and 12 are symmetrical with respect to each other (see FIG. 3), but the brush mounting member 3a on the left side in FIG. 3 is shown. However, since the brush mounting member 3b on the right side in FIG. 3 has a bilaterally symmetrical shape, the description thereof will be omitted.

Further, the curved surface 13 between the closed end surface 12 of the casing 1 and the side surface 14 of the casing 1 has a plurality of symmetrical positions on both sides of the rotary shaft 31 of the rotor protruding from the closed end surface 12 of the casing 1. The ventilation slots 15 are formed, and the plurality of ventilation slots 15 improve the ventilation of the inside and outside of the casing 1 and the motor. In particular, the closed end surface 12 of the casing 1 is used as a motor mounting plate or the like. Even when it is attached, since the ventilation slot 15 is formed in the curved surface 13, its breathability is not impaired and excellent cooling performance is provided.

In addition, as shown in FIG. 13, the part punched out when forming the ventilation slot 15 in the curved surface 13 of the casing 1 is left as the ventilation slot forming piece 16 in the casing 1, and It is possible to form the magnet receiving portion 17 for positioning and fixing the magnet mounted in the casing 1 by bending the ventilation long hole forming piece 16 inside the casing 1, and it is possible to obtain excellent air permeability ( In addition to having a cooling property, the positioning of the magnets in the casing 1 is facilitated, so that the motor can be easily assembled.

[0025]

[Effect of the invention]

 As described in detail above, the present invention has the following effects. That is, according to claim 1, since the brush mounted on the small DC motor is detachably attached to the end cap, the brush can be replaced and the life of the small DC motor can be extended. The long life of the DC motor can be achieved without being affected by the life of the DC motor, and the brushes can be easily replaced.This makes it easy to assemble a small DC motor, and at the same time, depending on the application and required performance of the small DC motor. Since the brushes can be replaced, a compact DC motor with greater usability can be provided.

According to the second aspect, since the plurality of ventilation elongated holes are formed in the curved surface connecting the closed end surface of the casing to the side surface of the casing, the ventilation of the inside and outside of the casing and the inside and outside of the motor is improved. In addition, the cooling performance of the motor is improved, the overheating of the bearing, the contact part of the brush and the commutator, or the coil formed in the rotor is prevented, and problems due to overheating of the small DC motor are prevented. According to claim 3, the portion punched out when forming the ventilation slot in the casing is left as a ventilation slot forming piece in the casing, and by bending this inside the casing, the magnet is placed in the casing. Since a magnet receiving part for positioning and fixing when mounting is formed, it is possible to easily assemble a small DC motor.

Further, according to claim 4, each of the pair of bearing support members rising from the ring-shaped fitting portion of the end cap and supporting the bearing portion is formed in a lattice shape by the plurality of bearing support pieces. Since it is formed on the end cap, air permeability inside and outside the end cap and inside and outside the motor is improved, cooling performance of the motor is improved, and the bearing, the contact part between the brush and the commutator, or the coil installed in the rotor is improved. It prevents overheating and prevents problems due to overheating of small DC motors.

[Brief description of the drawings]

FIG. 1 is an overall perspective view of a small DC motor of the present invention.

FIG. 2 is a front view of the small DC motor of the present invention.

FIG. 3 is a left side view of the small DC motor shown in FIG.

4 is a right side view of the small DC motor shown in FIG. 2. FIG.

5 is a plan view of the small DC motor shown in FIG. 2. FIG.

6 is a bottom view of the small DC motor shown in FIG. 2. FIG.

FIG. 7 is a front view of an end cap of the small DC motor of the present invention.

FIG. 8 is a plan view of an end cap of the small DC motor of the present invention.

9 is a cross-sectional view taken along the line X-X 'in FIG.

FIG. 10 is a front view of a brush member of the small DC motor of the present invention.

FIG. 11 is a view on arrow Y in FIG.

FIG. 12 is a view as viewed in the direction of the arrow Z in FIG. 11;

FIG. 13 is a cross-sectional view showing a magnet receiving portion formed in a ventilation elongated hole portion of a casing.

[Explanation of symbols]

 1 casing 2 end caps 3a, 3b pair of brush mounting members 4 brush 5 terminal 6 ring-shaped fitting portion 7 pair of bearing support members 8 bearing portion 9 brush support portion 10 leaf spring portion 11 casing opening end 12 casing closing End surface 13 Curved surface of casing 14 Side surface of casing 15 Vent long hole 16 Vent long hole forming piece 17 Magnet receiving portion 22 Plural protrusions 23 Wall groove

Claims (4)

[Utility model registration claims] 1. An open end 11 on one side and a closed end face 12 on the other side.
And a rotor having a rotating shaft 31 arranged in the casing 1, and an end cap fitted to the open end 11 of the casing 1. 2, a coil to which a current is supplied from a commutator arranged around the rotary shaft 31 is arranged in the rotor, and a coil of the rotor arranged in the casing 1 is arranged in the end cap 2. A pair of brushes 4 for supplying an electric current through a commutator and a terminal 5 connected to the brushes 4 are attached to the rotary shaft 31 of the rotor.
Is supported by the bearing of the closed end surface 12 of the casing 1 and the bearing of the bearing portion 8 formed on the end cap 2, and a magnet is arranged in the casing 1 to install a pair of brushes 4 mounted on the end cap 2. And a small DC motor that rotates a rotor by supplying a current from a terminal 5 connected to the brush 4 to a coil arranged in the rotor through a commutator, and obtains a driving force from a rotation shaft 31 of the rotor. The end cap 2 is a pair of ring-shaped fitting portions 6 that fit into the open ends 11 of the casing 1 and a pair of standing-up portions that rise from the ring-shaped fitting portions 6 with the rotary shaft 31 of the rotor interposed therebetween. The bearing support member 7 and the bearing portion 8 supported by the pair of bearing support members 7 are provided, and the brush insertion space S is provided between the ring-shaped fitting portion 6 and the bearing portion 8. The opposing wall 18 that is formed and is opposed to the bearing portion 8 of the ring-shaped fitting portion 6 is formed perpendicularly to the rotating shaft 31 of the rotor, and has a plurality of protrusions 22 on the periphery thereof. The pair of bearing support members 7 rising from the ring-shaped fitting portion 6 has side walls 19 parallel to the rotation shaft 31 of the rotor and perpendicular to the facing wall 18 of the ring-shaped fitting portion 6. The bearing portion 8 has a wall groove 23 formed of a side wall 20 that is flush with the side walls 19 of the pair of bearing support members 7 and an inclined surface 21 that is inclined toward the side wall 20.
Further, the pair of brushes 4 mounted on the end cap 2 and the terminals 5 connected to the brushes 4 have a plurality of protrusions formed on the periphery of the opposing wall 17 of the ring-shaped fitting portion 6. 22 and a wall groove 23 formed in the bearing portion 8 are integrally formed with a pair of brush mounting members 3a and 3b that are engaged and held, and the pair of brush mounting members 3a and 3b are , Brush 4 and terminal 5 connected to brush 4
And a wall groove 23 of the bearing portion 8 which is formed of a metal plate having a spring property and which has a spring property.
The side wall 20 of the brush supporting portion 9 and a brush supporting portion 9 in which a brush supporting piece 26 for inserting the brush 4 into the brush insertion space S is formed, and an obtuse angle rising from the brush supporting portion 9 and the ring-shaped fitting portion 6 A pair of brushes having a brush 4 by engaging and disengaging the leaf spring portion 10 and the plurality of protrusions 22 with each other. A small direct current motor characterized in that the mounting members 3a, 3b can be attached and detached. 2. The casing 1 has a curved surface 1 between a closed end surface 12 of the casing 1 and a side surface 14 of the casing 1.
3 has a plurality of ventilation slots 15 and the plurality of ventilation slots 1
5. The small DC motor according to claim 1, wherein the reference numerals 5 are formed symmetrically with respect to the rotary shaft 31 of the rotor projecting from the closed end surface 12 of the casing 1. 3. The ventilation slot 15 is left inside the casing 1 as a ventilation slot forming piece 16 that is punched out when the ventilation slot 15 is formed in the casing 1, and the ventilation slot forming piece 16 is bent inside the casing 1. The small DC motor according to claim 2, wherein the magnet receiving portion 17 for positioning and fixing the magnet mounted in the casing 1 is formed. 4. A pair of bearing support members 7 that stand up from the ring-shaped fitting portion 6 of the end cap 2 and support the bearing portion 8 are each formed by a plurality of bearing support pieces 25 arranged in a grid pattern. The small direct current motor according to claim 1, wherein the small direct current motor is provided.