JP2503575B2 - Rotating electric machine - Google Patents

Description

The present invention relates to a rotary electric machine such as an electric motor and a generator, and is particularly suitable for use as a starter of an internal combustion engine in which a brush holder is assembled using a connecting member for a bracket. Involved in rotating electric machines.

[Prior Art] Conventionally, as shown in FIG. 5, a small motor has a positive side connecting terminal 130 and a negative side between an inner wall surface 111 of a cast aluminum bracket 110 and an end surface 121 of a cylindrical yoke 120. The brush holder 150 in which the connection terminal 140 is insert-molded is sandwiched, and the outer peripheral surface 151 of each is held by the inner peripheral wall 11 of the bracket 110.
2 or fitted and fixed to the inner peripheral wall 122 of the yoke 120.

Therefore, this type of small motor has a problem that the number of assembling steps is large. Further, since cast aluminum is used as the material of the bracket 110, there are problems that the manufacturing cost is high, the dimensional accuracy of the bracket 110 is poor, and cutting is required after casting.

As a solution to this problem, in Japanese Utility Model Laid-Open No. 61-58843, a bracket made of a thin plate is adopted, and a brush holder is insert-molded to this bracket, and the brush holder and the yoke are fitted together in a cage. A rotating electric machine is shown.

[Problems to be Solved by the Invention] In the conventional rotary electric machine having the above-described configuration, in consideration of heat resistance from the brush sliding portion, it is necessary to select a thermosetting resin as the material of the brush holder.

However, it is very difficult to adopt a thermosetting resin for insert molding, and since the thermosetting resin does not have good dimensional accuracy, there are problems such as the need for cutting the seal cage fitting part. there were.

An object of the present invention is to provide a rotating electric machine that can easily assemble a brush holder to a bracket made of a thin plate without performing complicated insert molding or cutting work.

[Means for Solving the Problems] A rotating electric machine according to the present invention includes a rotating shaft to which a contactor such as a commutator or a slip ring is fixed, a tubular portion that rotatably passes through the rotating shaft, and a tubular portion of the tubular portion. A bracket having a plate-shaped portion extending in the outer peripheral direction, formed by press-molding a thin plate, a brush holder for holding a brush that contacts the contact and is electrically connected to the contact, The bracket has the first fitting portion fitted to the inner peripheral surface of the tubular portion, and the brush holder fitted to the second fitting portion. A configuration including a connecting member that is attached to the shape portion is adopted.

[Operation] The rotating electric machine of the present invention has the following operation due to the above configuration.

The first fitting portion of the connecting member is fitted to the inner peripheral surface of the tubular portion of the bracket, and the second fitting portion of the connecting member is fitted to the brush holder, thereby connecting the brush holder to the connecting member. Since it is attached to the plate part of the bracket using
Eliminates the need for complicated insert molding and cutting.

[Effects of the Invention] The rotating electric machine of the present invention has the following effects due to the above configuration and operation.

The brush holder can be easily assembled to the bracket using the connecting member without performing complicated insert molding or cutting work.

[Embodiment] An embodiment of the rotating electric machine of the present invention will be described with reference to FIGS. 1 to 4.

1 and 2 show a main part of a motor unit 1 of a starter for an internal combustion engine for automobiles.

A motor unit 1 of a starter (rotary electric machine) A of an internal combustion engine for an automobile includes a commutator 11, a rotating shaft 12, an armature core 13, and an armature coil (not shown) that is a rotating conductor.
An armature B which is a rotor composed of the above, and a field C which is a stator composed of a cylindrical yoke 2 and a pole core 14 such as a ferrite magnet. Fifteen
Is a washer for adjusting the thrust of the armature B.

The yoke 2 is made of a ferromagnetic material, has a pole core 14 attached to the inner peripheral wall thereof, and has a cylindrical portion 21 that coaxially houses the rotating shaft 12,
A flange plate 25 is formed extending outward from the outer periphery of the rear end portion 22 of the tubular portion 21 and having a fastening hole 24 for fastening with a screw 23 to the bracket 5.

The commutator 11 electrically connects the armature coil and the fixed bracket 5 via the + side brush 3 and the − side brush 4.

The + side brush 3 is attached to the + side leaf spring 31.
This leaf spring 31 is connected to a spring portion 32 that also serves as a brush spring and a brush lead wire for bringing the + side brush 3 into contact with the surface of the commutator 11, and a + side terminal 34 that is insert-molded in a resin bush 33. It consists of a connecting part 35.
In order to stabilize the position of the plus side brush 3, the spring part 32 has two fulcrums 32 that come into line contact with the brush holder 7.
a is provided. The connecting portion 35 has a tubular portion 36 into which the tip of the + side terminal 34 is press-fitted, and a collar-shaped portion 37 formed at the end of the tubular portion 36. The collar-shaped portion 37 presses the brush holder 7 toward the bracket 5 by a springback action.

The − side brush 4 is attached to the − side leaf spring 41.
The leaf spring 41 includes a spring portion 42 that also serves as a brush spring and a brush lead wire for bringing the minus brush 4 into contact with the surface of the commutator 11, and a connecting portion 45 connected to the minus terminal 44. This spring portion 42 is provided on the negative side brush 4
In order to stabilize the position of, the two fulcrums 42a that make line contact with the brush holder 7 are provided. The connecting portion 45 has a rectangular tubular portion 46 into which the tip of the minus side terminal 44 is press-fitted, and a collar-shaped portion 47 formed at the end of the tubular portion 46. The collar portion 47 is
The spring holder action presses the brush holder 7 toward the bracket 5.

The bracket 5 is formed by pressing a thin plate such as an iron plate or an aluminum plate, and has a cylindrical portion 50 that rotatably inserts the rotary shaft 12, and a plate portion that extends in the outer peripheral direction of the cylindrical portion 50.
Having 51.

The tubular portion 50 has a first tubular portion 52 into which the holder plate 6 is press-fitted, and a second tubular portion 54 provided from the first tubular portion 52 via a step 53. An oil seal 55 for preventing the lubricating oil of the internal combustion engine from flowing into the starter A is press-fitted into the inner periphery of the second tubular portion 54.

The plate-shaped portion 51 includes a flange plate 56 having an inner wall surface fixed to the outer wall surface of the flange plate 25 of the yoke 2, and an annular plate 57 formed on the inner circumference of the flange plate 56.

The flange plate 56 of the yoke 2 is screwed onto the flange plate 56.
To form a fastening hole 58 and a mounting hole (not shown) for mounting on the internal combustion engine.

The holder plate 6 which is a connecting member is attached to the inner wall surface of the annular plate 57, and a terminal hole 59 for fixing the bush 33 in which the + side terminal 34 is insert-molded is formed.

The holder plate 6 is formed by pressing a thin plate such as an iron plate or an aluminum plate, is electrically connected to the bracket 5, functions as a reinforcing member for the bracket 5, functions as a positioning member for the brush holder 7, and also serves as the bracket 5.
It is used to take out the minus side terminal 44.
The holder plate 6 includes an annular flat plate portion 60 attached to the inner wall surface of the annular plate 57 of the bracket 5, and the flat plate portion 60.
Is extended rearward from the inner circumference of the
Inner plate portion which is a first fitting portion press-fitted into the tubular portion 52 of the
61 and an outer plate portion 62 that is a second fitting portion that extends in a direction orthogonal to the outer periphery of the flat plate portion 60 and is fitted with the brush holder 7.
It consists of and.

The flat plate portion 60 is formed by cutting out a part of the inner circumference and then bending the yoke 2 toward the front end portion of the yoke 2 to form the negative terminal 44.
Are integrally formed. Further, the flat plate portion 60 is formed with a terminal hole 63 into which the bush 33 in which the + side terminal 34 is insert-molded is inserted.

A bearing 64, which is a bearing that rotatably supports the rotating shaft 12, is attached to the inner surface of the inner plate portion 61. The bearing 64 is sandwiched between an inner peripheral projection 65 formed on the inner plate portion 61 and a step 53 formed on the tubular portion 50 of the bracket 5.

The inner surface of the outer plate portion 62 centers the brush holder 7. The outer periphery of the outer side plate portion 62 constitutes the tightening margin of the O-ring 66 together with the rear end portion 22 of the yoke 2 and the inner wall surface of the annular plate 57 of the bracket, so that the O-ring 66 closely contacts the respective wall faces without any gap. Therefore, the waterproof property can be improved.

The brush holder 7 includes a plus side brush 3 and a minus side brush 4.
And is integrally molded with a thermosetting resin such as a phenolic resin.

The brush holder 7 is composed of an annular wall 70 attached to the inner wall surface of the flat plate portion 60 of the holder plate 6, and a ring-shaped side wall 71 extending in the orthogonal direction from the outer periphery of the annular wall 70.

The annular wall 70 is provided on the tip side surface of the + side brush mounting portion 70a that determines the mounting position of the + side brush 3 in the axial direction, and at a position facing the brush mounting portion 70a. Determine the axial mounting position-side brush mount 70
b is provided.

On the outer periphery of the side wall 71, a fitting portion 72 fitted to the inner side surface of the outer plate portion 62 of the holder plate 6, and a stepped portion 73 in which the tip end portion of the yoke 2 extends from the fitting portion 72 in the z-direction. Is provided.

A step 74, which is slightly smaller than the plate thickness of the outer plate portion 62 of the holder plate 6, is formed between the fitting portion 72 and the stepped portion 73. On the inner peripheral surface of the stepped portion 73, two contact portions 73a that make line contact with the fulcrum 32a of the spring portion 32 of the + side leaf spring 31 and two contact portions that make line contact with the fulcrum 42a of the spring portion 42 of the − side leaf spring 41. The portion 73b is provided. As a method of fitting the inner peripheral surface of the outer side plate portion 62 of the holder plate 6 and the fitting portion 72 of the brush holder 7, a fitting method such as a cage fitting, an interference fitting, or an uneven fitting may be used. .

A substantially semicircular terminal projecting portion 75 is formed on the inner periphery of the side wall 71 located between the + side brush mounting portion 70a and the − side brush mounting portion 70b of the annular wall 70.

In the terminal projecting portion 75, the + side terminal 34 and the − side terminal 44 are projected, and the + side leaf spring 31,
It has an axial hole 76 into which the end of the − side leaf spring 41 is fitted, and an insertion groove 77 formed on the side of the axial hole 76 and through which the + side leaf spring 31 and the end of the − side leaf spring 41 are inserted.

A method for attaching the brush holder 7 to the bracket 5 of the starter A of the automobile internal combustion engine of this embodiment will be described with reference to the drawings.

First, a yoke 2 is manufactured by molding a ferromagnetic material into a mold, and a thin plate such as an iron plate or an aluminum plate is pressed into a predetermined shape to manufacture a bracket 5 and a holder plate 6, and a brush is made of a thermosetting resin. The holder 7 is manufactured in a predetermined shape.

Then, the bush 33 in which the + side terminal 34 is insert-molded is press-fitted into the terminal hole 59 formed in the annular plate 57 of the bracket 5, and the second tubular portion of the bracket 5 is further inserted.
Assemble the oil seal 55 into 54 by press fitting.

On the other hand, a bearing 64 is attached to the inner side surface of the inner side plate portion 61 of the holder plate 6, and a part of the inner periphery of the flat plate portion 60 is cut and raised to form the-side terminal 44.

Then, the inner plate portion 61 of the holder plate 6 is press-fitted into the first tubular portion 52 of the bracket 5 without cutting, and the terminal hole 59 of the bracket 5 is inserted into the terminal hole 63 of the holder plate 6. The more protruding bush 33 is inserted to fix the flat plate portion 60 of the holder plate 6 to the inner wall surface of the annular plate 57 of the bracket 5.

At this time, the step formed on the tubular portion 50 of the bracket 5
Since the bearing 64 is sandwiched between 53 and the inner peripheral projection 65 formed on the inner plate portion 61 of the holder plate 6, it is possible to prevent the bearing 64 from falling off the holder plate 6.

Next, the + side terminal 34 and the − side terminal 44, which are assembled in a state that they are projected on the flat plate portion 60 of the holder plate 6,
Of the brush holder 7 into the axial holes 76 of the respective terminal projections 75 of the brush holder 7,
The 72 is fitted into the outer side plate portion 62 of the holder plate 6 without cutting. At this time, the brush holder 7
Centering is performed by the inner side surface of the outer side plate portion 62, and the center line of the brush holder 7 and the center line of the rotating shaft 12 coincide with each other.

Then, the cylindrical portions 36, 46 of the connecting portions 35, 45 of the leaf springs 31, 41 are fitted into the axial holes 76 of the terminal projecting portion 75 while being press-fitted into the projecting portions of the positive side terminal 34, the negative side terminal 44. . After that, the positive side terminal 34, the negative side terminal 44 and the tubular portions 36 and 46 are connected by welding, so that the collar-shaped portions 37 and 47 are spring-backed as shown in FIG. Is pressed toward the annular plate 57 of the bracket 5. Therefore, the movement of the brush holder 7 in the axial direction with respect to the bracket 5 is restricted, and the brush holder 7 is attached to the inner wall surface of the annular plate 57 of the bracket 5 via the holder plate 6.

Then, the armature B is attached to the bracket 5. (In addition, the commutator 11 and the spring portion 3 of the leaf springs 31 and 41
Assemble the + side brush 3 and the-side brush 4 between 2 and 42. ) At this time, the leaf springs 31 and 41 have two fulcrums 32.
When the a and 42a are in line contact with the contact portions 73a and 73b of the stepped portion 73 of the brush holder 7, the plus side brush 3 and the minus side brush 4 are formed.
The mounting position of is stable, and the + side brush 3 and-side brush 4
Comes into contact with the surface of the commutator 11 at the optimum position.

The outer plate portion 62 of the holder plate 6 and the side wall of the brush holder 7 are attached to the rear end portion 22 of the yoke 2 to which the pole core 14 is assembled.
The stepped portion 73 of 71 is fitted in the cage, and the flange plate 25 of the yoke 2
The fastening hole 24 formed in the bracket 5 is aligned with the fastening hole 58 formed in the flange plate 56 of the bracket 5, and the bracket 5 is fastened to the yoke 2 by the screw 23.

Therefore, the bracket 5 and the brush holder 7 are easily assembled by fixing the brush holder 7 to the inner wall surface of the thin bracket 5 by using the holder plate 6 without performing complicated insert molding or cutting. be able to.

[Other Embodiments] In this embodiment, the rotating electric machine of the present invention is used as a starter for an internal combustion engine for automobiles. However, other electric motors and generators in which the rotating electric machine of the present invention has a brush slidingly contacting a commutator or a slip ring. It may be used for

In this embodiment, the inner peripheral protrusion is formed on the inner plate portion of the holder plate to prevent the bearing from coming off.However, the inner peripheral protrusion may be formed to the brush holder to prevent the bearing from coming off. You don't have to keep it in place.

In this embodiment, the inner plate portion of the holder plate to which the bearing is attached is press-fitted into the tubular portion of the bracket. However, even if the inner plate portion of the holder plate to which the oil seal is attached is press-fitted into the tubular portion of the bracket. Alternatively, the inner plate portion of the holder plate may be independently press-fitted into the tubular portion of the bracket.

In this embodiment, the leaf spring end is fitted in the axial hole and the insertion hole formed in the terminal protruding portion of the brush holder, but the axial hole and the insertion hole and the plate formed in the terminal protruding portion of the brush holder are inserted. The end of the spring may be an interference fit.

In this embodiment, the holder plate is used as the connecting member for attaching the brush holder to the plate-shaped portion of the bracket, but a cylindrical body or a plurality of arc-shaped bodies fitted in the cylindrical portion of the bracket may be used as the connecting member. , In this case,
The second fitting portion is fitted to the inner peripheral surface of the brush holder. Further, the first fitting portion does not have to be cylindrical and may be a plurality of arc-shaped plates or flat plates. Furthermore, the second
The fitting portion may be a convex portion or a concave portion that fits into a concave portion or a convex portion formed on the annular wall of the brush holder.

Although the thermosetting resin is used as the material of the brush holder in the present embodiment, metal may be used for the brush holder as long as the brush, the bracket and the connecting member are electrically insulated.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a main part of a motor portion of a starter for an internal combustion engine for an automobile adopting an embodiment of the present invention, and FIG. 2 is a starter for an internal combustion engine for an automobile adopting an embodiment of the present invention. FIG. 3 is a plan view showing the main part of the motor section, and FIG. 3 is a yoke, a bracket, a holder plate, and
FIG. 4 is an exploded view of a brush holder and the like, FIG. 4 is a sectional view of a connecting portion of a brush holder and a leaf spring adopting an embodiment of the present invention, and FIG. 5 is a sectional view showing a main part of a motor portion of a conventional small-sized motor. It is a figure. A in the figure: Starter (rotary electric machine) for internal combustion engine for automobiles, 2 ...
… Yoke, 3 …… + side brush, 4 …… − side brush, 5…
... Bracket, 6 ... Holder plate, (connecting member),
7: Brush holder, 11: commutator, 12: rotating shaft, 50
...... Cylindrical part, 51 …… Plate-shaped part, 61 …… Inner plate part (first fitting part), 62 …… Outer plate part (second fitting part)

Claims (1)

(57) [Claims] 1. A rotary shaft to which a contact such as a commutator or a slip ring is fixed, and (b) a tubular portion rotatably inserted through the rotary shaft, and an outer peripheral direction of the tubular portion. A bracket formed by press-molding a thin plate, which has a formed plate-like portion, and (c) a brush holder that holds a brush that contacts the contact and is electrically connected to the contact, (d) The first holder includes a first fitting portion that is fitted to the inner peripheral surface of the tubular portion of the bracket, and a second fitting portion that is fitted to the brush holder. A rotating electric machine comprising: a connecting member attached to a plate-shaped portion.