JPH11299190A - Resin molding apparatus of armature coil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a presser structure for preventing the coming off of the armature coils of a motor whereby the part cost and assembling cost of the motor can be reduced. SOLUTION: In this resin molding apparatus, providing protrusively inward in the radial direction of a die 2 coil-presser-oriented rib-form protruding portions 8 on the inner peripheral surface of the die 2 for molding the whole of an armature core 1, the number and lengths of the portions 8 are made nearly equal to the ones of respective core slots 1a of the armature core 1 correspondingly to the core slots 1a to provide the portions 8 so as to be protruded by a predetermined amount into the respective corresponding core slots 1a in the state of inserting the armature core 1 into the die 2 and setting it. As a result, making preventable the coming off of armature coils from the core slots 1a of the armature core 1 when molding the armature core 1, the attachments of conventional wedges for preventing the coming off of the armature coils are made unnecessary prior to molding the armature core 1. Therefore, making unnecessary the wedges, the part cost of a motor can be reduced, and making unnecessary their attaching processes, the manufacturing cost of the motor can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an armature coil resin molding apparatus for resin-molding an outer peripheral surface of an armature core with a coil wound between core slots.

[0002]

2. Description of the Related Art In a winding process of a motor, when a coil is wound between core slots of an armature core, the coil is wound so as to be received in the core slot. A part of the coil may jump out of the core slot due to the elastic restoring force of the coil. As a conventional structure for preventing the coil from popping out after the winding, there is a conventional structure in which a coil holding wedge is provided in a core slot as disclosed in, for example, Japanese Patent Application Laid-Open No. 6-233503.

[0003] In a device using the wedge as described above, as shown in FIG.
The wedge 11 having a width larger than the gap between adjacent ones of the 0 flange portions 10a is housed in the core slot 1a, and the wedges 11 are prevented from falling outward in the radial direction by the two flange portions 10a. The coil 7 received in 1a is prevented from protruding radially outward from the gap between the flanges 10a of the core teeth 10. Further, as disclosed in Japanese Patent Application Laid-Open No. 8-140318, a coil wound around a core is molded with resin so as to cover the entire core to prevent the coil from jumping out.

[0004]

However, in the above-described conventional coil pop-out prevention structure, the coil pop-out prevention by wedges requires wedges in the number of slots and also requires a wedge insertion step. .
Therefore, there has been a problem that the cost of the product increases due to the cost of parts and assembly of the wedge. Further, also in the resin mold, there is a problem that the coil is damaged by the final cutting of the outer periphery of the core.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems and to realize an armature coil pop-out holding structure which can reduce the cost of parts and the cost of assembly, the present invention provides a core for an armature core. Apparatus for resin-molding the outer peripheral surface of the armature core with the coil wound between the core slots, in order to prevent the coil wound between the slots from jumping radially outward from the core slot. A radially inward coil holding projection which can enter the core slot is provided on an inner peripheral surface surrounding the armature core of the device.

[0006] By doing so, resin molding can be performed while preventing the coil from popping out by the mold, and it is not necessary to prevent popping out by the wedge, so that the number of parts and the number of assembling steps can be reduced.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to specific examples shown in the accompanying drawings.

FIG. 1 is a side sectional view showing a main part of a molding apparatus for performing resin molding on an armature core 1 of a motor to which the present invention is applied. In the present molding apparatus, a cylindrical mold 2 with a bottom formed so as to be able to receive the armature core 1 in a state of being inserted in the axial direction, and an upper opening for closing the upper opening of the mold 2 in the drawing. A lid 3 is provided. A motor shaft support hole 2a is opened at the center of the bottom of the mold 2, and the motor shaft support hole 2a is provided.
a is shielded by an axial end of the inserted motor shaft 4 and a base 5 supporting the lower surface of the mold 2 in the drawing.

Before performing molding with the present molding apparatus,
The armature core 1 and the metal body 6 which finally becomes a commutator are coaxially integrated with the motor shaft 3 and the armature core 1
Has been completed. Note that, in the motor according to the present embodiment, the metal body 6 which is finally formed by dividing each segment in the circumferential direction and thereby serving as a commutator has a disc-like shape. The upper axial end face of the metal body 6 which finally becomes a commutator in the figure becomes a brush sliding contact face, and each lead wire portion of the coil 7 is joined to the lower axial end face of the figure.

The armature unit having completed the winding process as described above is inserted into the mold 2 in the axial direction as shown in FIG. 1, and a resin material is injected from the lid 3 side, so that the entire armature core 1 is formed. Is formed on the inner peripheral surface of the mold 2, as shown in FIG. 2, a rib-shaped coil pressing protrusion 8 protruding inward in the radial direction is provided corresponding to each core slot 1 a. They are provided with substantially the same length and the same number. When the armature core 1 is inserted and set in the mold 2 as described above, the coil holding projections 8 project into the corresponding core slots 1a by a predetermined amount as shown in FIG. It has become.

Therefore, the armature core 1 is connected to the mold 2
When inserting the core slots 1a, the core slots 1a and the coil holding projections 8 are aligned and inserted. When the armature core 1 is set in the mold 2, the coil holding protrusion 8 protrudes into the core slot 1 a.
The coil 7 in a is pressed radially inward from the outer peripheral surface of the armature core 1.

In order to make it easy for the coil holding projection 8 to rush into the core slot 1a when the armature core 1 is inserted into the mold 2, the coil holding projection 8 has a tapered shape in the insertion direction of the armature core 1. Is formed. The tapered shape is such that as the armature core 1 is inserted, the coil holding projection 8 advances into the core slot 1a. Therefore, the radially inwardly projecting amount of the coil holding projection 8 is larger on the bottom side than on the opening side of the mold 2.

In this manner, it is possible to prevent the coil 7 from jumping out of the core slot 1a during molding without attaching the wedge shown in the conventional example. Then, as described above, the resin material is injected and the entire armature core 1 is molded. When the resin material is solidified, the resin-coated armature core 1 is taken out of the mold 2 and the process proceeds to the next step.

Since the resin material does not flow into the portion where the coil pressing protrusion 8 protrudes into the core slot 1a, there is also an effect that the injection amount of the resin material can be reduced as compared with the conventional example.

In the above-described embodiment, the mold 2 having the coil holding projection 8 integrally formed on the inner peripheral surface is used.
As shown in FIG. 2, a plate-shaped coil holding core 9 as a coil holding protrusion is formed separately from the mold 2 and provided so as to be able to advance and retreat in the radial direction with respect to the inner peripheral surface of the mold 2. good. In this case, when the armature core 1 is inserted into the mold 2, the coil holding core 9 is retracted, and after the armature core 1 and the device 2 are positioned before the injection of the resin material, the coil The pressing core 9 protrudes into the core slot 1a.

By doing so, the core slot 1a is provided in a helical shape as shown in the above-described embodiment. Although it is necessary to insert it by twisting it together, in the mold structure shown in FIG. 4, the insertion work becomes easy. Although the commutator of the motor according to the embodiment of the present invention has a disk shape, the present invention can be practiced with other commutator shapes, for example, a cylindrical shape.

[0017]

As described above, according to the present invention, it is possible to prevent the coil from protruding from the core slot at the time of molding by the coil holding projection provided on the mold for molding the armature core. Since there is no need to attach a wedge for preventing coil protrusion, the cost of parts can be reduced because the wedge is not required, and the manufacturing cost of the motor can be reduced since the mounting step is not required.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a main part of a molding apparatus for performing resin molding on an armature core of a motor to which the present invention is applied.

FIG. 2 is a partially cutaway perspective view of a mold according to the present invention.

FIG. 3 is a partially enlarged cross-sectional view taken along the line of FIG. 1;

FIG. 4 is a view corresponding to FIG. 3, showing another embodiment of the mold.

FIG. 5 is a partially enlarged cross-sectional view of an armature core and a mold showing a conventional molding procedure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Armature core, 1a core slot 2 Die, 2a Motor shaft support hole 3 Lid 4 Motor shaft 5 Base 6 Metal body 7 Coil 8 Coil holding projection 9 Core for coil holding 10 Core teeth 10a Collar part 11 Wedge

Claims (4)

[Claims] 1. An armature core having a coil wound between said core slots in order to prevent a coil wound between the core slots of said armature core from projecting radially outward from said core slot. An apparatus for resin-molding an outer peripheral surface, wherein an inner circumferential surface surrounding the armature core of the apparatus is provided with a radially inward coil holding protrusion that can protrude into the core slot. Characteristic resin molding equipment for armature coils. 2. The resin molding device for an armature coil according to claim 1, wherein the inner peripheral surface of the device is formed in a cylindrical shape that can be inserted and removed in an axial direction of the armature core. 3. The coil pressing protrusion extends in a longitudinal direction of the core slot, and protrudes radially inward from a near side to a far side in an insertion direction of the armature core. The resin molding device for an armature coil according to claim 2, wherein the resin molding device is formed in a tapered shape. 4. The resin molding apparatus for an armature coil according to claim 1, wherein the coil holding projection is provided so as to be displaceable with respect to the mold.