JPH0519274B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an apparatus for manufacturing a brush sliding sleeve for a vehicular alternator installed in a vehicle such as an automobile or a motorcycle.

[Prior Art and Problems to be Solved by the Invention] In general, this type of vehicle alternator has a resin part made of an insulating material, which has a shaft hole formed in the center and whose outer peripheral surface part has a circular cross section. A pair of slip rings are integrally provided on the outer peripheral surface of the resin part, and the base end is integrally fixed to the inner peripheral surface of each slip ring with the base end embedded in the resin part, and the tip part is integrally provided on the outer peripheral surface of the resin part. A brush contact sleeve is provided, which is comprised of a pair of terminals protruding in the outer radial direction at opposing angles of 180 degrees from the brush contact sleeve.

This brush-sliding sleeve is produced by setting the slip ring to which the pair of terminals are fixed in advance in a mold, and injecting a resin material in this state.

However, when manufacturing a conventional brush contact sleeve, as shown in FIG. At the beginning of injection, it flows into the mold avoiding the terminal part that creates resistance to flow, and in the final stage it fills into the terminal part that has high resistance. There was a risk that the resin material would not flow sufficiently into the narrow gap between the molds, resulting in unfilling, or that welding would occur, resulting in problems of deterioration in molding accuracy and strength.

[Means for Solving the Problems] In view of the above-mentioned circumstances, the present invention was devised for the purpose of providing a manufacturing device for a brush contact sleeve for a vehicle alternator that can eliminate these drawbacks. The resin part is made of an insulating material and has a shaft hole formed in the center and has a circular cross section on the outer peripheral surface, a pair of slip rings integrally provided on the outer peripheral surface of the resin part, and a base. A pair of terminals whose ends are embedded in the resin part and are integrally fixed to the inner peripheral surface of each slip ring, and whose tips protrude radially outward from the outer peripheral surface of the resin part at opposite angles of 180 degrees. In the vehicular alternator equipped with a brush sliding contact sleeve, the brush sliding contact sleeve is manufactured by injecting a resin material into a mold in which a slip ring to which the pair of terminals is fixed is preset. In doing so, the shaft hole split die for forming the shaft hole has a roughly elliptical cross section;
The tip of the terminal is located on both sides in the short axis direction, while the injection port for injecting the resin material into the assembled mold is located at the center of the shaft.
It is characterized by being set at a position eccentric to either one of the major axis directions of the ellipse of the split mold for the shaft hole.

According to the present invention, with this configuration, the molding accuracy of the brush contact sleeve can be significantly improved.

[Example] Next, an example of the present invention will be described based on the drawings. In the drawings, reference numeral 1 denotes a rotor of a vehicle alternator, and the rotor 1 includes a rotor shaft 2, a rotor core 3 around which a rotor coil 3a is wound, and a brush formed by the manufacturing apparatus of the present invention. It is formed by integrally fixing the sliding sleeve 4 in an externally fitted manner.

The brush contact sleeve 4 includes a resin part 5 made of an insulating resin material, a pair of slip rings 6 integrally provided on the outer peripheral surface of the resin part 5, and a base end embedded in the resin part 5. It is formed by a pair of terminals 7 and 8, which are fixed to the slip ring 6 in a state of In addition to being connected to the rotor coil 3a, a brush (not shown) is in sliding contact with the slip ring 6 in an elastic manner.

On the other hand, reference numeral 9 denotes a mold constituting the manufacturing apparatus for the brush sliding sleeve 4, and the mold 9 has a slip ring 6 (in addition,
As shown in FIG. 2, this slip ring 6 is a pair of slip rings that are integrated with a cutting allowance 6a), and then a resin material is injected into the brush sliding sleeve 4. It will be molded. Incidentally, the molded brush sliding contact sleeve 4 is subjected to a cutting process on the inner circumferential surface and the outer circumferential surface in order to ensure accuracy. It is designed to be divided into two rings 6b and 6c which are insulated from each other.

Now, the mold 9 includes a first split mold 10 for molding the shaft hole surface of the brush contact sleeve 4, and a second split mold 10 that is fitted onto the first split mold 10 and molds the outer circumferential surface of the brush contact sleeve 4. A split mold 11, a third split mold 13 that fits onto the second split mold 11 and forms the outer peripheral surface of the flange 5a formed at the end of the brush contact sleeve 4 on the rotor core 3 side, and a resin material injection port. 14a is provided as described later, and is constructed by combining a plurality of split molds such as a fourth split mold 14 for molding the side surface of the brush contact sleeve 4 on the rotor core 3 side on a mold base 15. A recess 13a for setting the tips of the terminals 7 and 8 is formed at the upper end of the third split mold 13, and a presser mold member 1 is inserted into this recess 13a.
A convex portion 16a formed on the terminal 6 is fitted to press the terminals 7 and 8.

Further, the second split mold 11 has an air vent hole 11a communicating from the inner circumferential surface to the outer circumferential surface, and an air vent groove 11b connected to the air vent hole 11a on the outer circumferential surface. is the air vent groove 1 above.
1b is formed, and these are connected to each other so that one end opens to the outer circumferential surface of the brush contact sleeve 4 and the other end opens to the outside of the mold 9. At the time of injection of material, air remaining in the mold 9 is extracted to the outside. In other words, the air remaining in the mold 9 passes through the small gap between the slip ring 6 and the inner circumferential surface of the second split mold 11 into the air vent hole 11a.
Even if some resin material were to enter the gap at this time, there would be no problem since the outer peripheral surface of the brush contact sleeve 4 would be cut after molding as described above. do not have.

On the other hand, the first split mold 10 for forming the shaft hole has a substantially elliptical cross section,
Moreover, the terminals 7 and 8 are located on both sides in the short axis direction.
The terminals 7 and 8 of the brush contact sleeve 4 are configured so that the portion where the terminals 7 and 8 are buried therein is thick and the portion that avoids the terminals 7 and 8 is thin.

On the other hand, the injection port 14a is eccentric in a direction away from both the terminals 7 and 8 with respect to the axis of the brush contact sleeve 4, that is, in either one of the long axis directions of the ellipse in the first split mold 10. It is formed on the lower surface of the fourth mold 14 in such a manner as to be positioned at the same position as shown in FIG.
Then, as seen in the plan view shown in FIG. 3, the resin material injected from the injection port 14a flows into a position away from both terminals 7 and 8, and is divided toward both terminals 7 and 8, and then flows into each terminal. After passing through the terminals 7 and 8, they merge on the opposite side of the injection port 14a, so that the weld position where the resin materials separated in this way merge is a position that avoids both terminals 7 and 8. is set to . In other words, the resin material injected as described above is
The flow is divided and flows towards terminals 7 and 8,
The width of the flow path is widened at the terminals 7 and 8, making the flow smoother, making it difficult for the resin to flow into the terminals 7 and 8 and the second split mold 1.
1 and also into the gaps between the terminals 7, 8 and the slip ring 6. The inner peripheral surface of the brush contact sleeve 4 formed into an oval shape by the first split mold 10 is as follows.
As mentioned above, it is cut into a perfect circle after molding.

In the embodiment of the present invention configured as described above, the resin material injected from the injection port 14a flows into the mold 9 from a position where the wall becomes thin, avoiding both terminals 7 and 8, and becomes thick. The flow is divided towards both terminals 7 and 8. The resin material is placed between the terminals 7 and 8 and the slip ring 6,
After sufficiently flowing into the narrow gap between the terminals 7 and 8 and the second split mold 11, they merge on the opposite side of the injection port 14a, and the merging position avoids both terminals 7 and 8. This will be the thinner part. Moreover,
When the resin material flows through the terminals 7 and 8, the channel becomes wide and the flow becomes smooth, so that the resin material flows more actively into the gap between the terminals 7 and 8. Therefore, there is no problem such as the gap in the terminals 7 and 8 being unfilled or welds occurring, which is the case with conventional products where the injected resin material inevitably merges at the terminals 7 and 8. The resin material is reliably filled even in the small details, and as a result, it is possible to prevent a decrease in strength and to significantly improve the molding accuracy of the brush contact sleeve 4.

[Operations and Effects] In short, the present invention is constructed as described above, so that the resin material injected from the injection port flows into the mold from the thin part avoiding both terminal parts, and then increases in thickness. The liquid flows to both terminal parts, and then joins at a thin part on the opposite side of the injection port.

As a result, the flow path of the injected resin material becomes wider at the terminal area, and its flow is promoted, so that the injected resin material merges at the terminal area, like the conventional injection from the center position of the shaft hole. This will not happen, and the resin material will actively flow into the gap between the terminal parts. Therefore, unlike conventional products where the injected resin material inevitably merges at the terminal part, there are no problems such as unfilled gaps in the terminal part and welds, and the details of the terminal part are not affected. Since the resin material is reliably filled, it is possible to prevent a decrease in strength, and the molding accuracy of the brush contact sleeve can be significantly improved, making it easy to create a brush contact sleeve with excellent reliability. This means that it can be manufactured in

[Brief explanation of drawings]

The drawings show an embodiment of the apparatus for manufacturing a brush contact sleeve for a vehicle alternator according to the present invention, in which FIG. 1 is a front view showing the rotor of the generator, and FIG. 2 is a mold. FIG. 3 is a cross-sectional view of the mold showing the flow of the injected resin material, and FIG. 4 is a cross-sectional view of the mold showing the conventional example. In the figure, 4 is a brush contact sleeve, 5 is a resin part, and 6
1 is a slip ring, 7 and 8 are terminals, 9 is a mold, 10 is a first split mold for forming a shaft hole, and 14a is an injection port.

Claims (1)

[Claims] 1. A resin part made of an insulating material with a shaft hole formed in the center and an outer circumferential surface having a circular cross section, a pair of slip rings integrally provided on the outer circumferential surface of the resin part, and a base end made of a resin part. A brush slide consisting of a pair of terminals that are integrally fixed to the inner peripheral surface of each slip ring while being embedded in the resin part, and whose tips protrude radially outward from the outer peripheral surface of the resin part at opposite angles of 180 degrees. In a vehicle alternator equipped with a contact sleeve, when manufacturing the brush contact sleeve by injecting a resin material into a mold in which a slip ring to which the pair of terminals is fixed is preset, a shaft hole is formed. The split mold for the shaft hole for forming the shaft hole has a substantially elliptical cross section, and is set so that the terminal tips are located on both sides in the short axis direction. The inlet of
1. An apparatus for manufacturing a brush contact sleeve for a vehicle alternator, characterized in that the sleeve is set eccentrically in one of the major axis directions of the ellipse of the split mold for the shaft hole with respect to the shaft center.