JPH0323816Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a small motor, particularly a small motor in which the brush mounting plate and the case lid are not integrated but are separate parts.

[Prior art and its problems]

When assembling a conventional small motor, a brush mounting plate is assembled after a large diameter oil washer is assembled at the end of the rotor's commutator.
Set the brush on the commutator during assembly (ballistic contact)
In order to do this, it is necessary to open the brush attached to the brush mounting plate to a greater extent than the outer diameter of the oil washer. This causes the brush arm to bend excessively, causing deformation or "sagging" in the brush arm. Further, in order to open the brush, it is necessary to make a hole in the case lid for opening the brush, which has disadvantages such as electrical noise leakage.

[Purpose and structure of the idea]

An object of the present invention is to provide a small motor that overcomes the above-mentioned drawbacks.

The present invention consists of a motor case having one bearing and a magnet attached thereto and an opening, a rotor provided inside the motor case and having a rotating shaft to which a commutator is attached, and a brush arm having brushes attached thereto. and a brush base having a terminal; a brush mounting plate provided at the opening of the motor case so that the brush comes into elastic contact with the commutator; In a small motor, the brush base of the brush body is formed by a locking piece and a case lid which is provided on the brush mounting plate and is fixed to the motor case. The brush mounting plate has a commutator escape hole in the center thereof through which the rotating shaft passes through, and a terminal hole into which the brush base of the brush body can be press-fitted, and the terminal hole is It is characterized by having a wall surface that engages with the locking piece of the brush base, and a protrusion that guides the tongue piece of the brush base.

〔Example〕

FIG. 1 is a partial sectional view showing the overall structure of a small motor according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view for explaining the assembled state of the small motor shown in FIG.

1 and 2, 1 is a motor case, 2 is a magnet, 3 and 4 are bearings, 5 is a rotating shaft, 6 is a rotor, 7 is a commutator, and 8 is a commutator 7
9 is a brush arm 11 that supports a brush 10 and a terminal 1.
14 is a brush mounting plate that holds the brush body 9, and 15 is a case lid fixed to the motor case so as to overlap the brush mounting plate.

The brush mounting plate 14 and the case lid 15 are constructed as separate parts, and the brush mounting plate 14 is made of an insulating material such as synthetic resin, and the case lid 15 is made of the same metal material as the motor case 1, such as aluminum. There is.

The motor case 1 is cylindrical and has an opening 16. A commutator escape hole 17, which is a hole for allowing the commutator 7 to escape, is provided in the center of the brush mounting plate 14, and a plurality of protrusions 18 are provided in the peripheral portion of the brush mounting plate 14. There is. These protrusions act as a cushioning material when fixing the case lid 15 to the motor case 1, and also absorb machining dimensional errors and deformations of the motor case 1, the brush mounting plate 14, and the case lid 15, and prevent variations in component dimensions. It works to prevent rattling caused by gaps caused by The brush mounting plate 14 further includes a plurality of recesses 19 through which a plurality of pawl receivers (to be described later) of the case lid 15 pass.
is provided at the periphery. The case lid 15 has a concave bearing holding portion 20 that holds the bearing 4, and is provided with a plurality of terminal boss holes 22 through which the plurality of terminal bosses 21 of the brush mounting plate 14 protrude. It is being Furthermore, a plurality of concave pawl receivers 24 are provided on the peripheral edge of the case lid 15 to receive locking pawls when the open end 23 of the motor case is crimped when the case lid 15 is fixed to the motor case 1. It is provided.

To assemble the above-mentioned small motor in which the brush mounting plate 14 and the case lid 15 are configured separately, first,
The assembly consisting of the rotating shaft 5, the rotor 6, and the commutator 7 is assembled into the motor case 1 through the opening 16, and then the brush mounting plate 14 with the brush body 9 attached thereto is inserted into the commutator escape hole 1.
The commutator 7 and rotating shaft 5 are passed through the motor case 7 and fitted into the opening 16 of the motor case 1 to be assembled. In this case, the brushes 10 of the brush body 9 attached to the brush mounting plate 14 are pressed so as to contact each other by the elastic force of the brush arm 11, so that the brushes 10 are brought into elastic contact with the commutator 7. To do so, the brush 10 must be opened. This is done by attaching a brush opening jig to the commutator 7 in advance, and assembling the brush mounting plate 14 into the motor case opening 16 while passing the brush opening jig through the commutator relief hole 17 of the brush mounting plate 14. Later, the brush opening jig is removed from the commutator 7 and the brush 10 is brought into elastic contact with the commutator 7, or an automatic machine tool is inserted through the commutator escape hole 17 of the brush mounting plate 14 without using the brush opening jig. You can do it by leaning. In either method, the oil stopper washer 8 is assembled in a later assembly process, so it is unnecessary to make the brush opening dimension larger than the diameter of the oil stopper washer 8.

After assembling the brush mounting plate 14 into the motor case opening 16, the oil stopper washer 8 is attached to the commutator 7.
Incorporate it into the end of the Next, the case lid 15 is fitted into the opening 16 of the motor case 1 so as to overlap the brush mounting plate 14 and assembled. This incorporation is
The claw receiving part 24 of the case lid 15 passes through the corresponding recess 19 of the brush mounting plate 14, and the brush mounting plate 14
This is done so that the terminal boss 21 passes through the terminal boss hole 22 of the case lid 15. Finally, the open end 23 of the motor case 1 is crimped to fix the case lid 15 to the motor case 1.

Hereinafter, parts directly related to the present invention will be explained.

FIG. 3 is a diagram for explaining the brush body 9. FIG. 3A is a plan view of the brush body 9, and FIG. 3B is a cross-sectional view taken along line A-A' in FIG. 3A. There is.

Brush arm 1 with brush 10 attached
1 has a location 2 on the brush base 13 whose tip end is the terminal 12 at its base 25.
6 and 26' are integrated by spot welding, for example, to form the brush body 9. A plurality of saw blade-shaped locking pieces 27 are formed on the edge between the terminal 12 of the brush base 13 and the welding location, and a tongue piece 28 formed by cutting and bending is formed on the flat part. . This tongue piece 28 is bent toward the side to which the brush arm 11 is welded, as shown in FIG. 3B.

FIG. 4 shows two brush bodies 9 as described above,
Fig. 9 is a view of the brush mounting plate 14 with the brush 9' attached thereto, as seen from the commutator side. The commutator side of the brush mounting plate 14 has two brush bases 29, 29' to which the brush bodies 9, 9' are attached (actually there are four brush bases, but two of them are used. ) and a wall portion 31 in which the commutator relief hole 17 is raised.
A recess 32 is formed by.

FIG. 5 is a diagram for explaining the structure of the brush base 29. FIG. 5A is a diagram showing the brush base 29 to which the brush body 9 is not attached, and FIG. 5B is a diagram shown in FIG. - Sectional view at A', Figure 5C
is a sectional view taken along line BB' in FIG. 5A.

The brush base 29 has a terminal hole 33 penetrating from the brush base to the terminal boss 21 side, and as shown in FIGS. 5A and 5C, one side wall 34 of this terminal hole 33 has a A semi-cylindrical protrusion 35 for pressing and fixing the brush base 13 and a tongue piece 28 provided on the brush base 13.
A prismatic protrusion 36 is provided for guiding. Both of these protrusions 35 and 36 extend in parallel from the brush base 29 toward the terminal boss 21, and a guide groove 37 is formed between the protrusions 35 and 36.

FIG. 6 is a diagram showing a state in which the brush body 9 is press-fitted into the terminal hole 33 as described above.
Figures A and B correspond to Figures A and B, respectively.

Attaching the brush body 9 to the terminal hole 33 is as follows:
The brush base 13 is press-fitted into the terminal hole 33 so that the tongue piece 28 of the brush body 9 is guided by the guide groove 37 until the terminal 12 protrudes from the terminal boss 21. The brush base 13 is
The side walls 38 and 39 of the terminal hole 33 are pressed by the pressing force of the protrusion 35 and the tongue piece 28.
[See FIG. 5C] and the saw blade-shaped locking piece 27 of the brush base 13 restrict the position of the brush base 13 and therefore the brush body 9 to the terminal hole 3.
It is held firmly within 3. Therefore, vibration of the brush arm base 25 due to vibration of the brush 10 is prevented.

Next, although it is not directly related to the present invention, the assembly structure of the motor case 1, brush mounting plate 14, and case lid 15 in assembling the small motor of this embodiment will be explained.

FIG. 7 is a view seen from the case lid 15 side to show the state in which the case lid 15 is fixed to the motor case 1, and shows the terminal boss hole 2 of the case lid 15.
Terminal boss 21 and terminal 12 that protrude from terminal boss 2 are omitted in the figure.

FIG. 8A is a sectional view taken along line X-X′ shown in FIG.
FIG. 8B is a sectional view taken along Y-Y′ shown in FIG.
FIG. 8C is a sectional view taken along line Z-Z' in FIG.

A motor case stepped portion 40 is formed on the inner peripheral surface of the motor case near the opening 16 of the motor case 1, and a brush mounting step portion 41 that comes into contact with the stepped portion 40 is formed on the brush mounting plate 14. It is provided. As shown in FIGS. 8B and 8C, when the brush mounting plate 14 is fitted into the motor case opening 16 during assembly, the stepped portion 41 of the brush mounting plate 14 comes into contact with the stepped portion 40 of the motor case 1. Brush mounting plate 14 is positioned relative to motor case 1.

Further, as shown in FIGS. 8A and 8C, when the case lid 15 is fitted into the motor case opening 16 so as to overlap the brush mounting plate 14, the bottom of the pawl receiver 24 of the case lid 15 The claw receiving bottom part 4 is
2 passes through the recess 19 of the brush mounting plate 14 and comes into contact with the motor case step 40, so that the case lid 15 is positioned with respect to the motor case 1.

The case lid 15 is fixed to the motor case 1 by caulking the motor case opening end 23, as described above. Due to this crimping,
The locking claw 43 cut out by the opening end 23 is bent and locked in the claw receiving part 24 of the case lid 15 as shown in FIGS. Fixed.

When fixing the case cover 15 to the motor case 1 in this way, the plurality of protrusions 18 provided on the peripheral edge of the brush mounting plate 14 come into contact with the case cover 15. Acts as a buffer material when Furthermore, these protrusions 18 function to absorb machining dimensional errors and deformations of the motor case 1, brush mounting plate 14, and case lid 15, thereby preventing rattling due to gaps caused by variations in the dimensions of these parts.

〔effect〕

According to the present invention, the oil stopper can be attached to the end of the commutator after the brush mounting plate is assembled, so when the brush mounting plate is assembled,
Since the size of the brush opening when the brush is brought into elastic contact with the commutator can be reduced, deformation or sagging of the brush arm will not occur.

In addition, since the brush body is firmly held on the brush mounting plate, vibration of the brush arm base due to brush vibration is prevented, allowing stable commutation and reducing vibration of the motor itself. can.

[Brief explanation of drawings]

Fig. 1 is a partial sectional view showing the overall structure of a small motor that is an embodiment of the present invention, Fig. 2 is an exploded perspective view for explaining the assembled state of the small motor shown in Fig. 1, and Fig. 3A. is a diagram showing the brush body, FIG. 3B is a sectional view taken along line A-A' in FIG. 3A, and FIG.
Figure 5A is a diagram showing the base of the brush, Figure 5B is a diagram showing the brush base.
5C is a sectional view taken along line BB' shown in FIG. 5A, FIG. 6A is a view showing the brush body attached to the brush base,
FIG. 6B is a sectional view taken along line A-A' in FIG. 6A;
Fig. 7 is a diagram showing a state in which the case lid is fixed to the motor case, Fig. 8A is a cross-sectional view taken along line X-X' shown in Fig. 7, and Fig. 8 B is a cross-sectional view taken along line Y-Y' shown in Fig. 7. 8C is a cross-sectional view taken along line Z-Z' in FIG. 7. In the figure, 1 is a motor case, 2 is a magnet, 3 and 4 are bearings, 5 is a rotating shaft, 6 is a rotor, 7 is a commutator, 8 is an oil washer, 9 is a brush body, 10 is a brush, and 11 is a brush arm, 12 is a terminal, 13 is a brush base, 14 is a brush mounting plate,
15 is a case lid, 27 is a locking piece, 28 is a tongue piece, 2
Reference numeral 9 indicates a brush base, 33 indicates a terminal hole, and 35 and 36 indicate protrusions, respectively.

Claims (1)

[Claims for Utility Model Registration] A motor case to which one bearing and a magnet are attached and which has an opening, a rotor which is provided inside the motor case and has a rotating shaft to which a commutator is attached, and a brush to which the brushes are attached. A brush body consisting of a brush arm and a brush base having a terminal is attached to the brush mounting plate provided at the opening of the motor case so that the brush comes into elastic contact with the commutator, and the other bearing is attached. In the small motor, the brush base of the brush body has a through hole through which the terminal passes, and a case lid provided on the brush mounting plate and fixed to the motor case. and a tongue piece formed by cutting and bending, and the brush mounting plate has a commutator escape hole in the center thereof through which the rotating shaft passes through, and a terminal hole into which the brush base of the brush body can be press-fitted; A small motor characterized in that the terminal hole has a wall surface that engages with the locking piece of the brush base, and a protrusion that guides the tongue piece of the brush base.