JPH0416619Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention relates to DC motors, and in particular, to improvements in the brush holding structure and bearing structure thereof, and is effective for use in small motors, for example. Regarding.

[Prior Art] Some conventional small motors have a rotor shaft that is rotatably supported by a self-aligning bearing member installed in an end bracket near a commutator to which the rotor shaft is fixed. In such a small motor, the self-aligning function of the bearing member reduces the difficulty of aligning the rotor shaft.

[Problem that the invention attempts to solve]

However, in such small motors, since a bearing member with a self-aligning function is installed in the end bracket, the rotor shaft swings when assembling the yoke to the end bracket, making it difficult to assemble the motor. There is a problem in that it hinders automation.

An object of the present invention is to provide a DC machine that can prevent the rotor shaft from swinging during assembly work and promote automation of the assembly work.

[Means for solving problems]

In the DC machine according to the present invention, a brush holder is disposed near the bearing member, and the protruding portion of the brush holder is brought into contact with the end face of the commutator when the end bracket is assembled, so that the rotor shaft can be roughly fixed. It is characterized by being protruded so as to maintain a vertical state.

[Effect]

According to the above-mentioned means, when the end bracket is assembled, the protrusion comes into contact with the end face of the commutator, thereby maintaining the rotor shaft in a substantially vertical state. , the other end of the rotor shaft can be fitted into the bearing member of the yoke.

〔Example〕

FIG. 1 is a vertical cross-sectional view showing a small motor which is an embodiment of the present invention, and FIGS. 2 and 3 are vertical cross-sectional views showing the same during assembly.

In this embodiment, the motor 1 as a DC machine includes a housing 2, and the housing 2 has a yoke 3 formed in a substantially cylindrical shape with one end open and the other end closed, and It is composed of an end bracket 4 which is fitted over the end bracket 4. Oil-impregnated bearing metals (hereinafter sometimes referred to as bearing metals) 5 and 6 as bearing members are disposed in the closing wall of the yoke 3 and in the center of the end bracket 4, respectively, and both metals 5 and 6 are made of metal. They are held by holders 7 and 8, respectively. Felts 9 and 10 are arranged adjacent to the bearing metals 5 and 6 and held by metal holders 7 and 8, respectively, and the felts 9 and 10 are designed to absorb oil. The bearing metals 5 and 6 have a convex spherical outer shape, and exhibit a self-aligning function by rotating in a three-dimensional direction relative to the metal holders 7 and 8.

A rotor shaft 11 is installed on the center line within the housing 2, and this shaft 11 has both bearing metals 5,
It is rotatably supported by 6. Rotor shaft 1
A plurality of thrust rings 12 are provided at one end of the 1.
The bearing metal 5 is arranged so as to sandwich the bearing metal 5 so that it abuts against a sleeve fixed to the armature of the rotor shaft 11 on the commutator side, and against a stopper ring fitted on the rotor shaft 11 on the opposite side from the commutator. and is hard-packed.
The position of the rotor shaft 11 in the axial direction is regulated by thrust rings 12 on both sides. Rotor shaft 1
1, an armature 13 is disposed and fixed in the middle part, and the armature 13 is disposed on the inner circumferential surface of the yoke 2 so as to face a plurality of magnets 14 disposed at approximately equal intervals in the circumferential direction. It is set up. A commutator 15 for supplying power to the armature 13 is arranged and fixed to the rotor shaft 11 at the end on the end bracket 4 side.

A brush holder 16 is fitted into the end bracket 4 so as to face the commutator 15, and the brush holder 16 is integrally molded from synthetic resin. The brush holder 16 is formed into a circular ring shape having approximately the same diameter as the end bracket 4, and is arranged and fixed so as to come into contact with the inner end surface of the end bracket 4. The brush holder 16 has a pair of accommodating parts 17 which are arranged to face each other with a phase difference of 180 degrees and are formed into a substantially square cylindrical shape. They are each housed in a slidable manner so as to come into sliding contact with the outer circumferential surface of the commutator 15 under pressure.

A protrusion 20 is provided on the inner edge of the brush holder 16.
is formed into a ring shape with an L-shaped cross section. They are arranged concentrically so as to surround the outer periphery of 6.

Next, the action will be explained.

A pair of brushes 1 held in a brush holder 16
When power is supplied to the armature 13 from 8 and 18 through the commutator 15, the magnetic flux of the armature coil (not shown) cuts the magnetic field of the magnet 14, causing the rotor shaft 11 to rotate around the bearing metals 5 and 6. .

Since the bearing metals 5 and 6 contain lubricating oil, the rotor shaft 11 and the metals 5 and 6 are sufficiently lubricated. This lubricating oil becomes easy to flow due to rotational friction heat, etc., and flows out to the outside. However, brush holder 1
6 surrounds the bearing metal 6, the spilled oil is caught by the protrusion 20 and prevented from flowing out, and the felt 1
It is recovered by being absorbed by 0.

By the way, when assembling the motor 1, the rotor shaft 11 to which the armature 13 and commutator 15 are fixed is fitted into the bearing metal 6 on the end bracket 4 side by inserting the protrusion 20 of the brush holder 16. At this time, brush holder 1
Without the protrusion 20 of 6, since the bearing metal 6 is formed into a convex spherical surface, the bearing metal 6 would rotate in a three-dimensional direction with respect to the metal holder 8, and the rotor shaft 1
1 tilts around the bearing metal 6 so as to swing its head.

However, in this embodiment, the brush holder 1
Since the protrusion 20 is integrally molded on the rotor shaft 1 and disposed so as to face the end face of the commutator 15, as shown in FIG.
When the commutator 1 is fitted into the bearing metal 6 and stands vertically, it is lowered by the weight of the armature 13, etc., so that the downward end surface of the commutator 15 rests on the upper surface of the protrusion 20 and receives its own weight. At this time, since the end face of the commutator 15 and the protrusion 20 are in a horizontal plane, the rotor shaft 11 applies its entire weight to the protrusion 20, thereby standing vertically on the protrusion 20.

In this standing state, as shown in FIG. 3, by covering the rotor shaft 11 with the yoke 8, the other end of the rotor shaft 11 is fixed to the
can be easily inserted into the In other words, by aligning the yoke 3 with the end bracket 4 and lowering it vertically relatively, the work of assembling the end bracket 4 and the yoke 3 can be automated.

According to the embodiment described above, the following effects can be obtained.

(1) By forming the protruding part on the brush holder in an annular shape so as to face the end face of the commutator, the end face of the commutator can be received by the protruding part, so it is easy to attach the rotor shaft to the brush holder during motor assembly work. Therefore, it is possible to temporarily support the motor, and as a result, work efficiency in assembling the motor can be improved.

(2) By forming a protrusion on the brush holder to surround the bearing metal, it is possible to prevent the lubricating oil from the bearing metal from leaking out, thereby preventing the oil from reaching electrical equipment parts such as commutators and impairing their functions. damage can be prevented.

(3) By integrally molding the protruding part on the brush holder, the number of parts can be reduced and the number of work steps can be reduced, increasing work efficiency and productivity. can.

(4) By integrally molding the protruding part on the brush holder, the support structure for the protruding part can be omitted, so the protruding part can be formed into a thin plate, and as a result, the commutator and the bearing metal can be easily connected. By setting the gap small, the axial size of the motor can be reduced.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and may be modified without departing from the gist thereof.
It goes without saying that various changes are possible.

For example, the brush holder is not limited to being integrally molded using resin, and the protruding portion is not limited to being molded simultaneously with the brush holder, but may be constructed as a separate piece and protruded by an appropriate means such as welding. You may.

The protrusions are not limited to being formed in a circular annular shape, but at least three protrusions are partially formed in the circumferential direction so that the rotor axis is approximately vertical by receiving the end face of the commutator when the end bracket is assembled. It may be placed in

The shapes, structures, etc. of the bearing metal, commutator, end bracket, and rotor shaft are not limited to those of the embodiments described above, and can be appropriately selected depending on the conditions.

[Effect of idea]

As explained above, according to the present invention, by providing the protrusion on the brush holder, the protrusion receives the end face of the commutator and maintains the rotor shaft approximately vertically when the end bracket is assembled. As a result, automation of assembly work can be promoted.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view showing a small motor which is an embodiment of the present invention, and FIGS. 2 and 3 are longitudinal cross-sectional views showing the same during assembly. 1...Motor (DC machine), 2...Housing,
3...Yoke, 4...End bracket, 5,6
... Oil-impregnated bearing metal (bearing member), 7, 8 ... Metal holder, 9, 10 ... Felt, 11 ... Rotor shaft, 12 ... Thrust ring, 13 ... Armature, 14 ... Magnet, 15 ... . . . Commutator, 16 . . . Brush holder, 17 . . . Brush accommodating portion, 18 . . . Brush, 19 .

Claims (1)

[Scope of Claim for Utility Model Registration] (1) The rotor shaft is rotatably supported in the vicinity of the commutator to which it is fixed by a bearing member with a self-aligning function provided on the end bracket of the housing. In a DC machine,
A brush holder for slidingly contacting the brush with the commutator is disposed near the bearing member, and the brush holder has a protrusion that contacts the end face of the commutator when the end bracket is assembled, thereby causing the rotor shaft to move. A direct current machine characterized by a protruding structure that maintains a vertical state. (2) The brush holder is integrally molded using resin into a substantially disk shape, and the protruding portion is formed into a ring shape with an L-shaped cross section and is integrally molded with the brush holder. A DC machine according to claim 1.