JPH0139086Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Technical Field of the Invention) The present invention relates to a small motor, and particularly to a small motor having a cover plate in which brushes and the like are supported by an insulator.

(Technical background and problems) Conventionally, terminals and brushes for supplying voltage to the commutator from the outside have been fixed to the cover plate of a small motor with brushes, and the fixed cover plate has been attached to the motor case of the small motor. (outer cylinder).

Since the cover plate is molded only from electrically insulating resin and the brushes, terminals, etc. are mounted thereon, it is deformed due to shrinkage after molding, plasticity of the resin, etc., and is difficult to hold accurately.

For this purpose, holes are generally made in a metal, for example iron, substrate for electromagnetic shielding, and the terminal portion of the brush is inserted into the hole and resin molded to electrically insulate it and fix it in a predetermined position. I was gone.

However, as will be described later with reference to FIG. 1, in order to hold and mold the terminal portion in the hole of the metal substrate, for example, approximately at the center, an automatic placement device is required, and moreover, It was necessary to use a vertical molding machine in order to mold both sides of the mold, making it difficult to use a horizontal molding machine.

In addition, resin molding is performed from both sides of the hole in the metal board, and the board is shaped into a cylindrical shape to increase the area of the part that contacts the motor case (outer cylinder) of the small motor and to stabilize it mechanically. It was also difficult to perform press processing, etc.

(Purpose and structure of the invention) The purpose of the invention is to solve the above-mentioned problems, and a terminal hole is provided in the center of a protruding boss made of an insulator for inserting and fixing the terminal of the brush device. At the same time, by press-fitting and fixing the protruding boss into the metal substrate,
To attach a brush device to a metal substrate in an electrically insulated state with a simple structure in a motor case of a small motor, and to firmly fix the metal substrate to an outer cylinder of the small motor. Therefore, the small motor of the present invention includes: a cylindrical motor case having a magnet on the inner wall; a rotor rotatably supported within the motor case; a rotating shaft fixed to the rotor; and the rotor. a brush device for supplying current to the motor case; the brush device is attached in an electrically insulated state, and a bearing for supporting the rotating shaft is provided in the center, and the brush device is engaged with the open end of the motor case. an insulator having a protruding boss configured with a terminal hole for causing a terminal portion, which is a voltage supply terminal of the brush device, to protrude to the outside of the small motor; and the metal substrate has a protrusion provided with a boss hole into which the protrusion-shaped boss provided on the insulator is press-fitted, and the boss on the insulator is formed on the metal substrate. The insulator is press-fitted into the boss hole to integrate the insulator and the metal substrate.

(Example of idea) The present invention will be explained in detail below based on the drawings.

Fig. 1 is a partial sectional view of an example of a cover plate of a conventional small motor, Fig. 2 is a right side view of an example of a cover plate of a conventional small motor shown in Fig. 1, and Fig. 3 is a portion of an embodiment of the present invention. 4 is an enlarged sectional view of the terminal portion of one embodiment of the present invention shown in FIG. 3, and FIG. 5 is an exploded partial perspective view of one embodiment of the present invention shown in FIG. 3.

In the figure, 1 is a rotor, 2 is a commutator, 3 is a rotating shaft, 4-1, 4-2 are bearings, 5 is a motor case, 6 is a metal board, 7-1 is a terminal, 7-
2 is a brush, 8-1 is a first insulator, 8-2 is a second insulator, 9 is a magnet, 10-1, 10-
2 is a hole, 11 is an insulator, 12 is a metal substrate, 12
-1 is a protruding part, 12-2 is a flange press-fitting part, 12
-3 flange, 13 a terminal hole, and 14 a boss.

The configuration and operation of the small motor will be briefly explained based on FIG.

One end of the rotating shaft 3 to which the rotor 1 and commutator 2 are fixed is connected via a bearing 4-1 to a motor case 5 made of a magnetic material and having a magnet 9 on the inner peripheral surface.
The other end is attached to a metal substrate 6 fixed to the motor case 5 via a bearing 4-2. A brush 7-2 is provided to supply current to the rotor 1 via the commutator 2.
A terminal 7-1 integrally formed with the terminal 7-1 is integrally molded with a first insulator 8-1 and a second insulator 8-2 and fixed to the metal substrate 6.

Terminal 7-1 of a small motor having the above configuration
When voltage is applied to the two terminals of brush 7-
2. A current is supplied to the rotor 1 through the commutator 2, and the rotor 1 is
rotates in a predetermined direction. The rotary shaft 3 at the left end in the figure is connected to a load.

As mentioned above, the metal substrate 6 of the small motor is generally designed to fix the rotating shaft 3 via the bearing 4-2, so strength, heat resistance, etc. are taken into consideration, and at the same time, it is used to shield undesired noise radio waves generated inside. For this reason, it has recently become common practice to use a cover plate having a substrate made of metal, particularly iron. For this reason, commutator 2
Terminals 7-1, which are current supply terminals integrated with the brush 7-2 that supplies current to the commutator 2 and the brush 7-2, are electrically insulated from the metal substrate 6, and are connected to the commutator 2 and the brush 7-2. There is a need for a simple, low-cost structure that can sufficiently withstand vibrations and heat generated by contact.

In the conventional case shown in FIG. 1, in order to electrically insulate the terminal 7-1 from the metal substrate 6, the terminal 7-1 is placed approximately in the center of the hole provided in the metal substrate 6.
-1 is arranged, and resin molding is performed from both sides of the metal substrate 6 using the illustrated first insulator 8-1 and second insulator 8-2.

Therefore, during manufacturing, a vertical injection molding machine is used to mold from both sides of the metal substrate 6, and the terminal 7-1 is positioned approximately in the center of the hole provided in the metal substrate 6. There were problems such as the need for an automatic placement device.

In addition, since molding is performed from both sides of the metal substrate 6, holes 10-1 for resin connection are shown in FIG.
1 and 10-2, and there was a problem in that electromagnetic noise generated inside the small motor would be radiated to the outside from the holes.

Furthermore, since the terminal 7-1 is also injection molded as an integral part, when fixing the metal board 6 to the motor case 5, conventionally the parts shown in FIGS. There is instability, and depending on the degree of caulking, the metal substrate 6 may be warped or deformed. Furthermore, in order to prevent undesired rotation of the metal substrate 6, it is necessary to provide a positioning mechanism as shown in FIG. 2, and the position of the positioning mechanism must be set individually depending on the application, such as forward rotation or reverse rotation. There was a problem that it had to be done.

Therefore, in the present invention, as shown in FIGS. 3 to 5, after separately molding an insulator 11 having a cylindrical boss with a rectangular terminal hole for fixing the terminal 7-1, The cylindrical boss of the insulator 11 is press-fitted into the cylindrical boss hole 14 provided in the metal substrate 12 and fixed, and the outer peripheral surface of the metal substrate 12 is formed into a cylindrical shape to form the motor case 5. It can be press-fitted and fixed. This will be explained below.

In Figure 3, 1 to 5, 7-1, 7 in the figure
-2 and 9 are the same as or have equivalent effect to those shown in FIG. 1, so their explanation will be omitted. Note that the metal substrate 12 and the insulator 11 integrated together are called a lid plate.

Reference numeral 11 in FIGS. 3 and 4 is an insulator that firmly fixes the terminal 7-1 to the metal substrate 12 in an electrically insulated state.

In the figure, a metal substrate 12 is made of metal, for example, iron that can be magnetically shielded, and the insulator 11 is fixed thereto. Further, the metal substrate 12 fixes the rotating shaft 3 to the motor case 5 via the bearing 4-2.

In the figure, reference numeral 12-2 denotes a flange press-fitting portion, which is press-fitted into the motor case 5, and serves to firmly fix the metal substrate 12 to the motor case 5.

Reference numeral 12-3 in the figure is a flange, which acts as a stopper when press-fitting the flange press-fitting part 12-2 into the motor case 5, and has a continuous flange-like shape as shown in the figure, or an intermittent shape. It can also be from.

FIG. 5A shows a perspective view of the insulator 11, in which a rectangular terminal hole 13 is provided approximately in the center of a cylindrical boss 11-1 provided in the insulator 11.
The terminal 7-1 is configured to be inserted into the terminal hole 13. As a result, the brush 7-
The terminal 7-1, which is integrally constructed with the insulator 2, is firmly fixed to the insulator 11, as will be described later.

FIG. 5B shows a perspective view of a metal substrate 12 made of iron, and a cylindrical protrusion 12 provided on the substrate 12.
-1 is provided with a boss hole 14, and the metal substrate 1
A flange press-fit part 12-2 for press-fitting into the motor case 5 and a flange 12 which is a stop part on the outer peripheral surface of 2.
-3 is provided.

By providing the boss hole 14 in the cylindrical protrusion 12-1, the contact area when the boss 11-1 shown in FIG. In addition, as shown in FIG. 4, the protruding portion of the boss 11-1 can be fixed more firmly, easily and reliably by mechanically caulking, caulking using heating or ultrasonic waves, or the like. Then, in order to press fit the boss 11-1 into the boss hole 14, the terminal 7 is inserted into the rectangular terminal hole 13 provided approximately at the center of the boss 11-1.
-1 is fixed by the boss 11-1.

In addition, as shown in FIG. 5B, a flange press-fit part 12-2 is provided on the outer circumferential surface of the metal substrate 12 to increase the contact area with the motor case 5, so that the metal substrate 6 can be caulked as shown in FIG. Compared to the case where the metal substrate 12 and the motor case 5 are firmly fixed, the positioning mechanism shown in FIG. 2 for stopping rotation is not required.

Therefore, it is possible to firmly fix the metal substrate 12 at any desired position that corresponds to forward rotation, reverse rotation, or forward and reverse rotation. Of course, a positioning mechanism may be provided as necessary for positioning when press-fitting the flange press-fitting part 12-2 into the motor case 5.

(Effect of the invention) As explained above, according to the invention, the insulator 1
A protruding boss 1 having a terminal hole 13 at 1
1-1, and the boss 11-1 is connected to the metal substrate 12.
The brush 7-2 and After separately manufacturing the integrated terminal 7-1, insulator 11, and metal substrate 12, it becomes possible to accurately and firmly attach them to the motor case 5 by a simple assembly operation.

[Brief explanation of the drawing]

Fig. 1 is a partial sectional view of an example of a cover plate of a conventional small motor, Fig. 2 is a right side view of an example of a cover plate of a conventional small motor shown in Fig. 1, and Fig. 3 is a portion of an embodiment of the present invention. 4 is an enlarged sectional view of the terminal portion of one embodiment of the present invention shown in FIG. 3, and FIG. 5 is an exploded partial perspective view of one embodiment of the present invention shown in FIG. 3. In the figure, 5 is a motor case, 7-1 is a terminal, 7-2 is a brush, 11 is an insulator, 12 is a metal board, 12-1 is a protrusion, 12-2 is a flange press-fit part, and 12-3 is a The flange, 13 represents a terminal hole, and 14 represents a boss hole.

Claims (1)

[Claims for Utility Model Registration] A cylindrical motor case 5 having a magnet 9 on the inner wall, a rotor 1 rotatably supported within the motor case 5, and a rotating shaft 3 fixed to the rotor 1. and brush devices 7-1 and 7-2 for supplying current to the rotor 1, and the brush devices 7-1 and 7-2 are installed in an electrically insulated state, and the rotating shaft 3 A small motor has a bearing 4-2 in the center that supports the motor case 5, and a metal substrate 12 that is engaged with the open end of the motor case 5. An insulator 11 having a protruding boss 11-1 with a terminal hole 13 for protruding a terminal portion, which is a terminal, to the outside of a small motor.
and the metal substrate 12 is provided with a protrusion 12-1 provided with a boss hole 14 into which the protrusion-shaped boss 11-1 provided on the insulator 11 is press-fitted, A small motor characterized in that a boss 11-1 on an insulator 11 is press-fitted into the boss hole 14 on the metal substrate 12, thereby integrating the insulator 11 and the metal substrate 12.