JPS5840904B2 - How to connect a slip ring to a rotating shaft - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a slip ring used for supplying field current in, for example, a vehicle alternator, and particularly relates to an improvement in the method of coupling a slip ring of this type to a rotating shaft. .

As is well known, in a vehicle alternator, a rotor including a field coil is coupled to a shaft rotated by an engine, and a slip ring is coupled to one side of the rotor.

The rotor is generally coupled by press-fitting the rotor into a knurled portion provided on the rotating shaft.

On the other hand, there are two ways to connect slip rings: one is to mold resin inside the slip ring to create a slip ring assembly, and press fit this onto the rotating shaft, and the other is to place the slip ring on the outer circumference of the rotating shaft and rotate it. A method of insert molding resin between a shaft and a slip ring is known.

Of these two methods, the latter method is superior to the former in that it requires fewer man-hours.

However, in this method of integrally molding the resin on the rotating shaft, a major problem is how to arrange the mold that creates the molding space for the resin on the rotating shaft.

In other words, this mold defines both axial end faces and the outer circumferential surface of the annular molded resin, and it has to be a split mold in order to be attached to the rotating shaft. Since there is a knurled portion for coupling the child, and a connection part is fixed to the slip ring, the installation of the split type is subject to significant restrictions due to these factors.

For this reason, in the past, it has been virtually impossible to manufacture a desirable slip ring integrated with a rotating shaft using such a method.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a method for coupling a slip ring to a rotating shaft, which can easily realize the method capable of reducing the number of man-hours described above.

An embodiment of the present invention will be described below with reference to the drawings.

In the figure, 10 is, for example, a rotating shaft of a vehicle alternator;
Reference numeral 11 indicates a knurled portion provided on a part of the rotating shaft 10 for press-fitting a rotor (not shown), and 12 indicates a slip ring coupling portion formed on the rotating shaft 10 on one side of the knurled portion 11. .

Further, 20.20' indicates two cylindrical slip rings, and 21.21' indicates a connection part whose one end is fixed by welding to the inner periphery of each slip ring.

Each connection par 21 , 21 ′ extends in the axial direction toward the knurled portion 11 side of the rotating shaft 10 .

Furthermore, 30 indicates a resin insert-molded between each slip ring 20, 20' and the slip ring coupling portion 12 of the rotating shaft 10, and 40 indicates a mold for forming a molding space for the resin 30. .

Therefore, in the present invention, the connection par 21 is installed in advance on the outer peripheral side of the slip ring coupling portion 12 of the rotating shaft 10.
The slip ring 20 is fixed to the slip ring 20 by combining the mold 40 holding the slip ring 20' with the rotating shaft 10.
．． The method is based on maintaining the resin 20' in a proper position, shaping the resin molding space, and insert-molding the resin 30 into this space.

Note that there are various methods for holding the slip rings 20, 20' within the mold 40, for example, the following method is used.

That is, the inner inner peripheral surface 42a of the mold 42, 42'.

42/a is partially formed with protrusions for gripping the slip rings 20, 20', and the mold 4 is divided into two so that the slip rings 20, 20' fit between the protrusions.
2, 42' are assembled onto the slip ring, and both dies 42, 42' are slid in the axial direction from the left side of the rotating shaft 10, and the second dies 42, 42' and the slip ring 20. 20'.

In this way, the second mold 42°42' is placed on the rotating shaft 10.
After assembling, the first mold 41 is assembled onto the rotating shaft 10 from the knurled part 11 side, and the through hole 41b of the first mold 41,
The connection par 41b is passed through 41b', the first and second molds are assembled, and the synthetic resin is insert-molded into these molds 40.

In this way, the slip rings 20 and 20' can be coupled to the rotating shaft 10 in an appropriate relationship using the resin 30 with a small number of man-hours.

At this time, in the present invention, in order to facilitate assembly of the mold 40, a stepped portion 13 is provided at one end of the slip ring coupling portion 12 of the rotating shaft 10 on the knurled portion side, so that the slip ring coupling portion 12 is closer to the knurled portion 11. The diameter is also set to be large.

In addition, a plate-shaped first mold 41 that defines one end surface of the resin 30 of the mold 40 is provided with a rotary shaft insertion hole 41a having a larger diameter than the knurled portion 11 of the rotary shaft 10 and a smaller diameter than the joint portion 12, and a connection. Hole 41b through which par 21.21' is inserted
.

41b/ is provided.

Then, this first mold 41 is inserted into the rotating shaft 10 in the axial direction from one end on the knurled part side, and brought into close contact with the step part 13 around the rotating shaft insertion hole 41a.
0 and the second mold 42, 42' described above.

The second mold consists of two radially separated molds 42, 42'.
This includes circumferential surfaces 42a, 42'a that define the outer peripheral surface of the resin 30, and an end surface 42b that defines the other end surface.
, 42'b are provided.

Then, the first and second molds 41, 42° 42'
The resin 30 is insert-molded into the space formed by the above, and after the molding, the mold is removed.

Note that the resin 30 is injected through an injection hole (not shown) that penetrates and connects the outside of the mold 40 and the end surface 42b inside the mold 42.

Now, in a conventional well-known type in which there is no stepped portion 13, a type corresponding to the first type is also divided in the radial direction of the rotating shaft 10, and is attached to the rotating shaft 10 from the radial direction. Must be removed.

The inner periphery of the mold must be in close contact with the rotating shaft, so if you try to insert or remove it from the axial direction, the knurling part 1
This is because 1 gets in the way.

However, in this case, the connection bars 21, 21'
(7) Treatment becomes a problem and must be extended in the radial direction.

This results in an increase in the size of the slip ring.

However, in the present invention described above, the first mold 41 can be inserted and removed from the axial direction due to the step portion 13, and the connection bar insertion holes 41b, 41 can be inserted into the first mold 41 from the axial direction.
By providing b', the resin 30 can be formed into an insert bottom shape while keeping the bars 21, 21/ in the axial direction.

As a result, according to the present invention, the excellent effect of making the slip ring small and connecting it to the rotating shaft with simple operations and at low cost is achieved.

[Brief explanation of drawings]

The figure is a schematic cross-sectional front view showing one step in the method of the present invention. 10...Rotating shaft, 12...Slip ring coupling portion, 13...Step, 20, 20'.
...Slip ring, 21, 21'...
Connection bar, 30...Resin, 41...
...First mold, 41a... Hole through which the rotating shaft is inserted, 41b... Hole through which the connection bar is inserted, 42, 42'... Second type.

Claims (1)

[Claims] 1. A slip ring 20.20' around the rotating shaft 10 via an insulating layer made of synthetic resin, and a connection ring 21.21 connected to the slip ring 20.20'.
In this method, a slip ring connecting part 12 is formed on the side of the knurled part 11 and has a larger diameter than the knurled part 11. and a step portion 13 formed between the slip ring coupling portion 12 and the knurled portion 11. a step of welding the connection par 21, 21' to the peripheral part; and internal circumferential surfaces 42a, 42'a, which are made of at least two divided molds and define the outer peripheral surface of the synthetic resin, and side end surfaces of the synthetic resin. Said inner circumferential surface 42 of the second mold 42, 42' having end face portions 42b, 42'b defining
A, 42'a are brought into contact with the outer peripheral surfaces of the slip rings 20, 20', and the second mold is attached to the slip rings 20, 20'.
．． 21', a step of covering the circumference of the slip ring coupling part 12 of the rotating shaft 10, and a rotating shaft insertion hole 41 having a larger diameter than the knurled part 11 of the rotating shaft 10 and a smaller diameter than the slip ring coupling part 12.
a1 and the connection par 21, 21' coupled to the slip ring, and a through hole 41b through which the force is inserted;
Inserting the rotary shaft 10 into the rotary shaft insertion hole 41a of the plate-shaped first mold 41 provided with the rotary shaft 41b',
a step of inserting the connection part 21° 21/ into the through holes 41b, 41b' and bringing the first mold 41 into contact with the stepped portion 13 of the rotating shaft and the side end surface of the second mold; , the side end surface of the first mold 41, the inner circumferential surfaces 42a, 42'a, and the end surfaces 42b, 42'b of the second mold. A material to be the synthetic resin is inserted into the space formed between the outer circumferential surface of the slip ring coupling part 12 of the rotating shaft 10 and the bottom of the material is inserted onto the slip ring coupling part 12 of the rotating shaft 10. A method for coupling a slip ring to a rotating shaft, comprising the step of fixing the slip ring via the synthetic resin.