JPH0662777U - Motor commutator - Google Patents

Abstract

(57) [Summary] [Purpose] Prevents oil from flowing into the commutator,
Prevents poor contact between the commutator and the brush. [Structure] An oil stop portion 12 is formed axially on a side surface of a commutator assembly 4 facing an oil-impregnated bearing 2 as a bearing. The oil flowing out from the oil-impregnated bearing 2 is stopped by the oil stopper 12 and therefore does not wrap around the surface of the commutator assembly 4.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a commutator for a motor, which is intended for various small motors.

[0002]

[Prior art]

 A structure shown in FIG. 5 is known as an example of a conventional small motor. An end of a rotary shaft 23 is rotatably supported by an oil-impregnated bearing 22 inside the projecting portion 21A of the case 21. A commutator 24 is fixed to the rotary shaft 23, and a segment 24A is attached to the commutator 24. The brush 25 is in sliding contact therewith. 26 is a thrust washer and 27 is a brush holder.

The oil washer 28 is fixed to the rotary shaft 23 by press fitting. A rotor 29 is fixed to the rotary shaft 23, and a stator 30 is fixed inside the case 21 so that the rotor 29 faces the rotary shaft 23. Reference numeral 31 is a rotor coil.

[0004]

[Problems to be solved by the device]

 By the way, in the conventional motor, when the oil cutting washer 28 is press-fitted into the rotating shaft 23, a gap 32 is formed between the rotating shaft 23 and the rotating shaft 23. There is a problem that contact failure occurs between the commutator 24 and the brush 25 because oil wraps around or the oil wraps around the oil washer 28 as shown by an arrow B.

The present invention has been made in consideration of the above problems, and prevents commutator oil from wrapping around the surface of the commutator and eliminates contact failure between the commutator and the brush. It is intended to provide.

[0006]

[Means for Solving the Problems]

 In order to achieve the above object, the present invention has a commutator fixed to a rotary shaft whose end is rotatably supported by a bearing, and a brush slidably contacting the commutator. Alternatively, it is characterized in that an oil stop portion formed in the axial direction is formed near the side surface.

[0007]

[Action]

 Since the oil stop portion is formed in the side surface or near the side surface of the commutator facing the bearing in the axial direction, the oil from the bearing is stopped or flowed by the oil stop portion. Therefore, since the oil is prevented from wrapping around the surface of the commutator, the poor contact between the commutator and the brush is eliminated.

[0008]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing a first embodiment of the present invention, in which 1 is a case, 2 is an oil-impregnated bearing provided inside the protruding portion 1A of the case 1, and 3 is an end portion rotatable by an oil-impregnated bearing 2. A rotating shaft 4 supported by the rotating shaft 4, a commutator set fixed to the rotating shaft 3, and a brush 5 slidably contacting the commutator set 4. Reference numeral 6 is a thrust washer, 7 is a brush holder, 9 is a rotor fixed to the rotating shaft 3, 10 is a stator fixed inside the case 1 so as to face the rotor 7, and 11 is a rotor coil. The commutator group 4 and the brush 5 are in contact with each other via the segment 4A.

Reference numeral 12 denotes an oil stop portion axially formed on a side surface of the commutator assembly 4 facing the oil-impregnated bearing 2. The oil stop portion 12 works so that the oil flowing out from the oil-impregnated bearing 2 does not wrap around the surface (cylindrical portion) of the commutator assembly 4 and the segment 4A.

According to such an embodiment, since the oil stop portion 12 is formed on the side surface of the commutator set 4, the oil flowing out from the oil-impregnated bearing 2 will be collected in the oil stop portion 12, and thus the commutator set 4 will be collected. It will not go around to the surface of 4. Therefore, it is possible to prevent electrical contact failure between the commutator group 4 and the brush 5. Further, since the oil drain washer as in the conventional case is not required, the number of parts can be reduced, and the assembling work can be simplified.

FIG. 2 shows a second embodiment of the present invention, showing an example in which an oil stop portion 12 is axially provided near the side surface of the commutator assembly 4 facing the oil-impregnated bearing 2. Even in the second embodiment, the same effect as in the first embodiment can be obtained only by changing the position of the oil stop portion 12.

FIG. 3 shows a third embodiment of the present invention, in which an oil stop portion 12 made of a through hole 12A is axially formed on the side surface of the commutator assembly 4 facing the oil-impregnated bearing 2. To show. FIG. 4 shows a sectional view taken along the line AA of FIG. Also according to the third embodiment, since the oil stop portion 12 including the through hole 12A is formed, the oil flowing out from the oil-impregnated bearing 2 flows through the through hole 12A, so that the oil can flow around the surface of the commutator assembly 4. There is no. Therefore, the same effect as the first embodiment can be obtained.

[0013]

[Effect of device]

 As described above, according to the present invention, the oil stopper formed in the axial direction is formed on the side surface of the commutator or in the vicinity of the side surface, so that the oil flowing out from the bearing can be prevented from wrapping around the surface of the commutator. Therefore, electrical contact failure between the commutator and the brush can be eliminated.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a first embodiment of the present invention.

FIG. 2 is a sectional view showing a second embodiment of the present invention.

FIG. 3 is a sectional view showing a third embodiment of the present invention.

4 is a cross-sectional view taken along the line AA of FIG.

FIG. 5 is a cross-sectional view showing a conventional example.

[Explanation of symbols]

 2 Oil-impregnated bearing 3 Rotating shaft 4 Commutator assembly 4A segment 5 Brush 9 Rotor 10 Stator 12 Oil stop 12A Through hole

Claims (1)

[Scope of utility model registration request] 1. A commutator is fixed to a rotary shaft whose end is rotatably supported by a bearing, and a brush is slidably contacted with the commutator. A commutator for a motor, characterized in that an oil stop portion is formed by drilling into the motor.