JPS62247736A - Armature of miniaturized rotary electric machine and manufacture thereof - Google Patents

Abstract

PURPOSE:To enable an armature to form an anchor portion to prevent a coil from jumping out easily, by pressing and slewing the outside circumferential surface of an armature core with a knurling tool having a sharp uneven section. CONSTITUTION:An armature core 1 is cylinder-shaped, on the outside circumfer ence of which multiple slot portions 1d are provided radially against an axis of rotation where in the slots a set of armature coils 2 are inserted. After the coils 2 are inserted into a slot 1d, a flange portion 1a is formed which is the anchor portion to prevent the coil from leaping out due to rotating centrif ugal force. The flange portion 1a is formed by pressing a slot 3 having sharp uneven section on the surface of circumference to the outside circumference of the armature core 1 and by rotating it on the circumference.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an armature for a rotating electric machine, and particularly to an armature for a small rotating machine having an open slot shape and a method for manufacturing the same.

[Conventional technology]

Conventionally, the armature of a small rotating electric machine (DC generator) used, for example, in an automobile starter, etc.
As is known from No. 1, a protrusion is provided at the entrance of the slot 1 of the iron core, and after the coil is wound, this is bent to form a locking part to prevent the coil from flying out due to centrifugal force. Structures that prevent this are known.

In addition, as another method of forming a locking part for preventing coil protrusion,
It is also known to caulk the vicinity of the thrower 1- one by one using a V-shaped cutting tool.

[Problem that the invention seeks to solve]

However, in the above-mentioned conventional technology, especially in the former case in which a locking projection is provided, the outer diameter of the iron core before processing becomes large due to the shape thereof, and the yield of the material becomes poor. Further, after the coil is assembled, the protrusions are pressed toward the slot side and brought down, which is a troublesome process.

In addition, in the latter case, it is difficult to position the iron core near the slot when caulking with a V-shaped cutter, and if a deviation occurs in this position, a protrusion to prevent the coil from flying out can be sufficiently formed.
Alternatively, the coil and its insulation coating may be damaged and the insulation may be destroyed. Furthermore, accurate positioning requires large-scale equipment, and producing armatures with different numbers of slots requires caulking each slot, making it unsuitable for quantification.

An object of the present invention is to provide an armature for a small rotating machine in which a retaining portion for preventing coil protrusion can be easily formed using relatively simple equipment, in view of the above-mentioned drawbacks in the prior art.
Another object of the present invention is to provide a manufacturing method thereof.

[Means for solving problems]

The object of the present invention is to suppress and turn at least a part of the outer circumferential surface of an armature core having a plurality of slots formed on its outer circumferential surface and into which coils are inserted by means of a knurling having a sharp uneven cross-sectional shape. This can be achieved by a method of forming a locking part for coil protrusion, or by an armature having an armature core having a coil protrusion prevention part formed in this way.

[Effect]

As the knurling having the uneven cross-sectional shape rotates in a suppressing manner, the surface of the core near the slot is laterally deformed, thereby forming a coil protrusion prevention locking portion near the slot opening.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS An armature for a small rotating machine according to the present invention and a method for manufacturing the same will be described below with reference to the drawings.

In FIG. 1, an armature core 1 is a laminated core made by stacking a plurality of punched silicon steel plates, for example, and has a cylindrical shape, and has a plurality of slots 1d on its outer periphery relative to the rotating shaft. They are arranged radially, and a set of armature coils 2 are arranged inside them. As is clear from the figure,
The above slot ld is used to facilitate winding of the coil.
It is a so-called open slot, and after the coil 2 is opened, a collar portion 1a is formed as a locking portion to prevent the coil from flying out due to centrifugal force of rotation.

According to the present invention, the slot 1a is formed by rotating the armature core 1 circumferentially while pressurizing the outer circumferential surface of the armature core 1 with a slot 3 having a sharp uneven cross-sectional shape on the circumferential surface. It is something.

In the enlarged view of FIG. 2, when the knurl 3 is pressed against the outer periphery of the armature core 1 under pressure, the tip of the surface convex portion 3a of the knurl 3 locally applies a large deforming force to the core 1. This deforming force compresses the iron core 1 and at the same time expands the iron core 1 in the circumferential direction by the convex tip portion 3a of the piece, as shown by the arrow in the figure. On the other hand, the stress is greatest near the outer circumferential surface of the iron core 1, and as the knurling 3 rotates, the iron core gradually expands in the circumferential direction, thereby forming a flange 1a that protrudes from the open end 1b of the slot 1c. do. Such stress decreases from near the outer periphery of the iron core 1 toward the inside of the iron core. Therefore, the shape of the flange portion 1a which is deformed and formed to protrude by this stress is such that the inner peripheral side of the slot IC has a curved shape, as shown in the figure. Such a flange portion 1a prevents the coil 2 from coming into contact with the centrifugal force caused by the rotation of the armature.
It does not damage the insulating layer coated on its outer circumferential surface.
The same applies to the press-forming operation of the flange portion 1a. Therefore, when an armature is manufactured by such a method, its insulation properties can be ensured to be sufficiently high, which leads to an improvement in small stoppages and the like.

FIG. 3 shows a perspective view of an enlarged cross-section of the protruding flange of the slot opening of the armature core 1 formed in this manner. An open slot IC and a set of coils 2 are placed inside the IC, and after that, a knurling is pressed and rotated on the surface of the iron core to form a flange 1a to prevent the coils from flying out. The state shown is as follows. Also, in this example, helical knurling, which will be explained later, is used.

The knurling 3 used in the above manufacturing method of the present invention will be described in detail below. The knurling 3 has a sharp uneven cross-sectional shape on its surface. In the above embodiment, the pitch of the convex portions is about 1/10 of the width of the slot. For example, for an armature core with a slot width of 3 millimeters (nl), a knurling 3 having the following shape is used.

Module 2 0.3 Pitch: 0.942 Furthermore, the effects of the present invention are not limited to the above-mentioned knurling shape, but can also be obtained by using knurling having a pitch in the range of about 1/10 to 172 of the slot width. Obtainable.

Furthermore, the shape of the knurling is not limited to the flat knurl shown in FIG. 4(a), but also the inclined (helical) knurling shown in FIG. 4(b).

Furthermore, the same effect can be achieved by using the iris-shaped knurling shown in FIG. 3(c). According to experiments, when the helical-toothed knurl shown in Figure 4(b) is used to suppress the rotation, the deformation force acting on the outer periphery of the core is concentrated in the direction perpendicular to the direction of the teeth of the knurling. However, it has been confirmed that the suppressed iron core member moves in the bevel tooth direction and the stress in the circumferential direction is increased, so that the protruding flange can be formed more effectively.

Due to the suppressed rotation of the knurls, the surface of the iron core becomes uneven, thereby increasing the surface area and increasing the effect of dissipating heat generated by armature current. On the other hand, the unevenness of the surface also affects the magnetic resistance of the core surface. Therefore, as in the embodiment shown later, the influence can be reduced by suppressing the knurling to form the flange portion not over the entire circumference of the iron core, but only over a portion of the circumference. The influence can also be reduced by adjusting the ratio of the pitch of the knurling to the slot width, and it has been confirmed that particularly good results can be obtained when the ratio is set to 1/10.

Next, a method of suppressing and turning the knurling will be described below. According to the present invention, in addition to simply pressing the iron core surface, the large stress generated locally by using the knurling having a sharp convex portion is used, so that the protruding flange can be easily pressed with a relatively small pressing force. can be formed into Further, since troublesome work such as positioning is not required, it can be easily carried out using relatively simple equipment, and the work is also simple. However, this pressing force is determined by the two dimensions of the material of the core, the slot width, the desired dimensions of the flange, etc.

5 and 6 show a specific method of laminating the armature core on the rotating shaft, further mounting the coil and commutator, and then rotating the armature 4 to suppress the knurling on the outer circumferential surface. . Although it is possible to perform the suppressing rotation of the knurling 3 over the entire outer circumference of the cylindrical core of the armature 4, the same effect can also be achieved by performing it only on the portions close to both ends, as shown in Fig. 5. Ru. Furthermore, as shown in FIG. 6, it is also possible to further securely prevent the coil from flying out by further pressing and turning the knurling 3 to provide a flange in the center. In addition, FIG. 5 shows a method for obtaining the same effect as the suppressing rotation of the iris-shaped knurling by simultaneously suppressing and turning other bevel-toothed knurlings 3' having different inclination directions when using the helical-toothed knurling 3. is shown. In FIG. 6, two knurls are placed in parallel and simultaneously pressed and turned against the surface of the armature core, and a coil protrusion prevention collar is formed by the second operation.

〔Effect of the invention〕

As is clear from the above, according to the present invention, the coil protrusion prevention part can be formed with a relatively small suppressing force and without the need for troublesome work such as positioning, and can be formed quickly using relatively simple equipment. It is possible to manufacture an armature for a small rotating machine, and also to provide an armature for a small rotating machine that has excellent insulation performance due to the shape of the coil protrusion prevention part.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a method of manufacturing an armature for a small rotating electrical machine according to the present invention, FIG. 2 is a partially enlarged diagram of FIG. FIG. 3 is a cross-sectional perspective view showing the formation of the coil protruding part in FIG. 2, FIG. and FIG. 6 is a diagram showing a specific method of rotating the knurling while suppressing the armature surface. DESCRIPTION OF SYMBOLS 1... Armature core, 1a... Coil protrusion prevention part, 1b... Core surface, 1c... Slot, 2...
・Coil, 3...knurling.

Claims (1)

[Claims] 1. An armature core formed by laminating a plurality of steel plates and having a plurality of slots on its cylindrical surface, and an armature coil inserted into the slot of the core. The slot has a protruding flange formed at the open end of the slot by pressing and turning a knurling having a sharp uneven cross-sectional shape on the circumferential surface to prevent the coil from flying out. The armature of a small rotating electrical machine. 2. The armature of a small rotating electric machine according to claim 1, wherein the outer circumferential surface of the armature core on which the knurling presses and turns is at least a part of the outer circumferential surface. 3. The armature for a small rotating electric machine according to claim 1, wherein the pitch of the knurling is in a range of about 1/10 to 1/2 of the width of the slot. 4. Form the armature core by laminating multiple disc-shaped steel plates,
Armature coils are wound around a plurality of slots provided on the cylindrical outer periphery of the iron core, and then a knurling having a sharp uneven cross section is pressed and turned on the cylindrical outer periphery of the iron core, thereby forming a collar for preventing the coils from flying out. 1. A method of manufacturing an armature for a small rotating electrical machine, the method comprising forming an armature of a small rotating electric machine. 5. The method of manufacturing an armature for a small rotating electric machine according to claim 4, wherein the suppressing rotation of the knurling is performed only on at least a part of the outer peripheral surface of the armature core. 6. In claim 4, the knurling is pressed and turned using a pitch that is within a range of about 1/10 to 1/2 of the width of the slot formed in the armature core. A method for manufacturing an armature for a small rotating electrical machine, characterized by: