JPS6263221A - Repro-joint outer race and its manufacturing device - Google Patents

Abstract

PURPOSE:To lower the molding pressure and reduce the weight of an outer race by providing a projection on the forming surface of a punch so that a recessed part is formed at the corresponding part among ball-rolling-grooves in the outer periphery of a cup part, thereby enhancing the fill-up performance of the material. CONSTITUTION:A triangular projection 3 is provided on a forming surface 1 of a punch 1. The projections of punches neighboring with each other are reversed in their directions, and the tip ends of the projections are extended to the middle in the direction of height of the punch 1. This punch 1 is built in into a mode. In coining, a recessed part 8 is created owing to the projection 3 at the corresponding part among the ball-rolling-grooves 7 in the outer periphery of a cup part 6 of an outer race 5. The weight of the race is reduced by the amount corresponding to this recessed part 8, and moreover the underfill at the end of the rolling groove can be prevented from occurring. Therefore, the accuracy of the groove can be enhanced without raising the forming pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a constant velocity joint having a cross groove, a so-called revlogi actuator race, and an apparatus for manufacturing the same.

(Prior Art) As shown in FIGS. 5 and 6, the outer race of the Rebrozi joint has six cross-shaped ball rolling grooves 12 on the inner surface of the cup portion 11. The inner races are brought together via balls (not shown) to form an integral constant velocity joint.

Conventionally, the ball rolling grooves 12 of the outer race 10 were generally finished by machining (reaming), but in recent years, the ball rolling grooves 12 have been finished in consideration of productivity and cost.
Many attempts have been made to create 12 by plastic working, and some have been put into practical use.

FIGS. 7 to 9 show an example of a mold structure for performing the plastic working. In these figures, 21 is a lower mold, 22 is an upper mold, and in the center of the lower mold 21 is disposed a mandrel body 24 integrally provided with a mandrel pin 23 on the outer periphery. The lower die 21 also includes the mandrel body 2.
A plurality of punches 25 are arranged in an annular manner around 4. This punch 25 is slidable on the lower mold 21, and has a curved flat molding surface 25 on the front surface thereof. An inclined surface 25b is provided on the rear surface. On the other hand, a work holding pad 26 is disposed on the upper mold 22 facing the mandrel main body 24, and is located around the work holding pad 26 and can be held on the inclined surface 25b of the punch 25. Inclined surface 27. A cam 27 is provided.

With this configuration, the workpiece W, which has been previously forged into a cup shape, is set on the mandrel 24, and the upper die 22 is lowered by driving the upper press ram. Then, first, the work holding pad 26 engages with the shoulder of the work W, and the work W is fixed on the lower mold 21. Then, the cam 27 engages with the punch 25, and the punch 25 is Inclined surface 25b127a
The wedge action causes the workpiece to move toward the W side using a cam method. Finally, the forming surface 25a of the punch 25 comes into contact with the cup portion W of the work W, and the work W is moved to the mandrel pin 2.
3. ! : Under the cooperative coining action of the mandrel body 24 and the punch 25, it is finally formed into a predetermined size,
An outer race 10 having a shaped ball transfer groove 12 is formed.

Incidentally, due to the coining described above, a burr 13 is generated on the outer periphery of the outer race 10 located between the punches 25, but this burr 13 is removed in a subsequent process.

(Problem to be solved by the invention) However, in the case of the above conventional mold structure, the coin f
During the molding process, the fill-up properties of the material on the inner diameter side of the outer race 10 were poor, and there was a risk of underfilling, particularly at the corner portion 10a (FIG. 8) corresponding to the rising portion of the mandrel bin 25.

For this reason, in the past, the forming force was increased to prevent the above-mentioned underfilling, but increasing the forming force not only leads to an increase in the equipment cost by increasing the size of the press machine, but also shortens the life of the mold. This is the cause of a decline in the quality of the product, and a fundamental improvement has been desired.

On the other hand, it is desirable that the outer race itself of Reprogi Soo India be as light as possible as long as the accuracy of the ball rolling groove 12 can be guaranteed, but if the above-mentioned fill-up property is taken into account,
The reality is that there is a limit to how much weight can be reduced, and it is not possible to reduce the weight as much as desired.

One object of the present invention is to provide a replica indoor outer race that is lightweight without sacrificing the accuracy of the ball transfer groove.

Another object of the present invention is to provide a manufacturing apparatus that can reduce molding force as much as possible by improving fill-up properties in coining and manufacturing a lightweight outer lace.

(Means for Solving the Problems) Therefore, the Rebrozi field indoor outer race according to the present invention is characterized in that a recess is provided in a portion corresponding to the ball transfer grooves on the outer periphery of the cup portion. do.

Furthermore, the manufacturing device for the internal outer race according to the present invention includes a mandrel for forming ball rolling grooves and a plurality of punches that move from the lateral direction with respect to the mandrel in a shifting cam method. The manufacturing apparatus is characterized in that the molding surface of each of the punches is provided with a protrusion that can be press-fitted onto the outer periphery of the cup portion of the roughly shaped material.

(Function) In the reprogy-into-outer lace having the above configuration, the outer lace itself is made as light as possible by providing the recessed portion on the outer periphery of the cup portion.

In addition, in the manufacturing equipment, the protrusion provided on the forming surface of the punch is press-fitted into the outer periphery of the cup portion of the rough profile material during coining, thereby promoting the flow of material toward the inner diameter side and improving fill-up performance. Accordingly, the molding pressure can be reduced, making it possible to downsize the press machine and extend the life of the mold.

(Embodiments) Hereinafter, embodiments of the present invention will be described based on the accompanying drawings.

Figure 1 (a), (b) and Figure 2 (a), (b) are
This figure shows the shape of a punch, which is a component of the apparatus for manufacturing a Replogi shoulder indoor outer lace according to the present invention.

The overall structure of the manufacturing apparatus is basically the same as that shown in FIGS. 7 and 8 above, so its explanation will be omitted here. In these figures, numerals 1 and 2 indicate two punches arranged adjacent to each other, each having a triangular protrusion 6.4 integrally protruding from its forming surface 1a, 2a.

The protrusion 3 and the protrusion 4Fi, adjacent punches 1.2, are oriented in opposite directions, and the tips of each are attached to the punches 1.2.
It extends to the middle of the height direction of 2. That is, when the punch 1.2 is assembled into the mold, the protrusion 3.4 forms a product (outer lace), which will be described later, as shown in FIG.
The balls are alternately positioned between the rolling grooves 6 of the 5 balls. Note that the protrusion distance of the protrusion 5.4 is preferably about sm at maximum.

However, when the punch provided with the protrusion 3.4 is assembled into the mold shown in Fig. 6.7 and coining is performed using the same procedure as described above, the amount of coining is Then, the protrusion 6.4 is gradually press-fitted into the outer periphery of the cup portion W of the workpiece W, thereby promoting the flow of the material inward.

The material flowing inwardly fills up sufficiently along the mandrel body 24 including the mandrel pin 23, thereby creating a ball transfer groove having a predetermined size and shape.

FIG. 4 shows the shape of the repro joint outer race obtained by the manufacturing apparatus having the above-mentioned mold structure. In the corresponding part there is provided a recess 8 created by said projection 3.4. That is, the outer lace 5Fi and the recessed portion 8 are lightened in weight.

In the above embodiment, the protrusion 5.4 has a triangular shape, but its shape is not limited, and can be, for example, trapezoidal. Further, its size is not particularly limited, and may be set as appropriate depending on the material and diameter of the outer race.

(Effects of the Invention) As described in detail above, the inventive outer race of the present invention has a concave portion in the portion corresponding to between the ball rolling grooves on the outer periphery of the cup portion. It was possible to reduce the weight of the ball transfer groove as much as possible without sacrificing its accuracy.

In addition, the outer lace manufacturing device has a protrusion on the forming surface of the punch that moves in a cam manner, so that the protrusion is press-fitted into the outer periphery of the cup portion of the rough profile during coining, thereby filling the material. The pressability was improved, and the molding pressure could be reduced accordingly, making the press machine more compact and extending the life of the mold.

[Brief explanation of drawings]

Figures 1 (a) and (b) and Figure 2 (a) (can) show the shape of a punch that is part of the repro joint outer lace manufacturing apparatus according to the present invention. Figure 1 (a
) and Fig. 2(a) are plan views, Fig. 1(b) and Fig. 2(b)
) is a front view, FIG. 3 is a developed view showing the arrangement of the protrusions provided on the punch with respect to the ball rolling grooves, FIG. Figures 5 and 6 are a plan view and a cross-sectional view showing the shape of a conventional replica indoor outer lace, and Figures 7 and 8 show the mold structure of a conventional manufacturing device that has the same basic structure as this manufacturing device. The sectional view and FIG. 9 are front views showing the shape of a conventional punch. 1.2... Punch 1a, 2. ... Molding surface 3.4 ... Protrusion 5 ... Outer race 6 ... Cup portion of outer race 7 ... Ball transfer groove 8 ... Recessed part 23 ... Mandrel pin 24 ... Mandrel body 27 ...Cam W...Rough-shaped material W--Cup portion of the rough-shaped material Patent applicant: Toyota Motor Corporation Alpha Chin Figure 4, Figure 1, Figure 1.2 - Claws la, 2a... Molding surface 3 .4... Anori Figure 2 (a) (b) Figure 3 Figure 7 Figure 5 Figure 6 Figure 8

Claims (2)

[Claims] (1) A repro joint outer race characterized in that a recess is provided in a portion corresponding to between the ball rolling grooves on the outer periphery of the cup portion. (2) In a repro joint outer race manufacturing apparatus equipped with a mandrel for forming ball rolling grooves and a plurality of punches that move laterally with respect to the mandrel in a cam method, a rough profile is formed on the forming surface of each of the punches. A manufacturing device characterized in that a protrusion that can be press-fitted is provided on the outer periphery of a cup portion.