JPH0736935B2 - Universal joint outer ring processing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Industrial field of application) The present invention relates to an apparatus for processing a universal joint, for example, an inner ball portion and a ball groove of an outer ring of a constant velocity joint. In order to produce a product that does not require final post-processing or has a small machining allowance, by cold-ironing the pre-formed material as shown in Fig. 8 to form the desired shape as shown in Fig. 8. Of the universal joint outer ring processing device.

(Prior Art) Conventionally, as a processing apparatus of this type, for example, Japanese Patent Publication No. 59-44
Some are described in Japanese Patent No. 138. This is provided with a radial guide groove (contact portion B in the publication) in the tip portion of a mandrel (guide punch 6 in the publication) which is step-molded so that the tip has a gradually smaller diameter. At the same time, the tip of the segment (inner circumference restraining die 5 in the publication) is fitted into the guide groove to position the tip of the segment, the segment base is extended in the radial direction, and is rotatably held on the mandrel side. It is said. The diameter of the segment can be reduced by changing the contact area between the inclined surface inside the segment and the mandrel stepped portion by the relative displacement between the segment and the mandrel, so that the segment can be extracted after processing the outer ring of the universal joint. It is said to have been done.

(Problems to be Solved by the Invention) However, the above-mentioned publication is generally treated as a consumable item, and a segment that requires high-precision machining extends the base portion in the outer diameter direction and holds it by rotation on the mandrel side. Therefore, the segment becomes large and the manufacturing cost and running cost are high.

In addition, a method of using a rotary shaft has been conventionally used for the rotary holding mechanism of the segment applied to the configuration as described in the above publication, but this requires a complicated maintenance work when replacing the segment and a large maintenance work. There was a problem that required time.

Further, in the above publication, since the mandrel must be stepped and the guide groove for radially guiding the guide groove for the segment must be provided at the tip end, the mandrel processing man-hour becomes large and the manufacturing cost and manufacturing time are increased. There was a great deal of inconvenience. In addition, since the above-mentioned publication uses a stepped mandrel and the segment is held away from the mandrel in the radial direction, even if a slight deviation occurs in the rotational support position of the segment, the segment The dimensions of the ball rolling groove forming part of
There was a problem that a very high level of dimensional accuracy was required.

[Structure of Invention]

(Means for Solving Problems) The present invention has been devised in view of the above, and its gist is to provide a rod-shaped mandrel whose tip portion is formed in a regular polygonal column shape and a substantially annular shape. The segment holding member slidably fitted on the mandrel and having a plurality of fitting grooves radially arranged on the tip side of the mandrel so as to correspond to the prismatic surfaces of the mandrel, and the base are respectively fitted to each other. The mandrel is fitted in the groove and extends in the axial direction of the mandrel. The inner surface of the mandrel is in contact with the prismatic surface of the mandrel. A plurality of segments, a ball hole formed in the segment holding member by tilting from the side surface of the fitting groove toward the base end side, and recessed in the base side surface of the segment corresponding to the opening of the ball hole Ball receiver Part, a ball which is urged by a spring inserted in the ball hole and is disposed between the ball hole opening and the ball receiving part and serves as a rotation supporting part of the segment, and a tip of the segment holding member. From the side of the ball hole, the ball hinge mechanism having a release hole having a diameter smaller than that of the ball, and a recess formed in the center of the inner peripheral surface of the segment toward the tip of the mandrel of the segment holding member. When the mandrel is located near the end of the mandrel due to the sliding displacement, the notch formed to allow the inward rotation of the segment tip and the inner surface of the segment tip contact the tip of the mandrel. In this state, the segment has a die for ironing the outer peripheral portion of the preformed material inserted into the inner surface portion, and a processing device for a universal joint outer ring.

(Operation) According to the present invention, the segment is inserted into the inner peripheral surface of the preformed material in a state where the inner surface of the segment front portion is in contact with the prismatic surface of the tip of the mandrel, and the outer periphery of the preformed material is obtained by the die. When ironing is performed, a product in which the outer peripheral portion, the inner surface portion and the rolling groove are formed in a predetermined shape is obtained.

After that, if the segment holding member is slidably displaced toward the tip of the mandrel to position the notch of the segment near the end of the tip of the mandrel, the inward rotation of the tip of the segment is allowed. Therefore, it is possible to reduce the segment diameter and extract the segment from the processed product. In addition, since the segment is rotatably held by the segment holding member by the ball hinge mechanism, if a small pin is inserted into the release hole and the ball is pushed into the ball hole against the biasing force of the spring, the ball and segment The segment can be easily removed by disengagement from the ball receiving portion, and the segment can be easily replaced.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the accompanying drawings. 1 to 6 show an embodiment of the present invention.
FIG. 1 is a cross-sectional view showing the apparatus of this embodiment, in which the left half of FIG. 1 shows the upper mold 1 at the top dead center position, and the right half of FIG. The state at the dead point position is shown. The upper mold 1 and the lower mold 2 are to be mounted between the rambeds of a press device (not shown). The lower die 2 comprises a mandrel 3, a lower die body 4, a lower die 5, a segment holding ring 6, a segment 7, and a biasing spring 8.

The mandrel 3 is formed in a rod shape and includes a cylindrical base portion 31 fixed to the lower mold body 4, and a hexagonal columnar tip portion 32 extending upward from the base portion 31. The lower die 5 is formed in a substantially annular shape and is slidably fitted on the mandrel 3. The lower inner peripheral surface of the lower die 5 is the outer peripheral surface of the mandrel tip portion 32, and the lower inner peripheral surface is the mandrel base end portion 31. It slides on the outer peripheral surface of.

As shown in FIG. 2, the lower die 5 has a flange 51 which is provided on the outer periphery of the lower portion so as to have an enlarged diameter, and is configured to be housed in a space 41 formed in the lower body 4. . The lower die 5 is slidable within a range in which the flange 51 is located between the bottom surface of the space 41 and the stopper surface 42 provided on the upper part of the space 41. Further, in the small-diameter step portion 55 provided on the upper part of the lower die 5, six fitting grooves 52 radially arranged corresponding to the prismatic surface of the tip portion 32 of the mandrel 3 are notched. Is formed in. In addition, the lower die 5 has a third and fourth
As shown in the figure, a ball hole 53 (only two of which are shown in FIG. 4) that is inclined downward from one side surface of the fitting groove 52 and extends downward is formed, and a small-diameter step portion of the lower die 5 is formed. 55 The top surface of the ball hole 53 has a smaller diameter release hole 54 on the upper surface than the ball hole 53.
Are pierced downward.

Further, the segments 7 are provided above the lower die 5 by fitting the base portions 71 into the fitting grooves 52 of the lower die 5, respectively. As shown in FIG. 3, the segments 7 surround the tip end portion 32 of the mandrel 3 and are radially formed. It is supposed to be placed. In addition, segment 7
The outer peripheral side of the base is held by the segment holding ring 6 fitted onto the small-diameter step portion 55 of the lower die 5. By the way, the segment holding ring 6 and the lower die 5 form a segment holding member. Segment 7 is first
As shown in the figure, the inner surface 72 of the mandrel 3 is in contact with the prismatic surface of the tip portion 32 of the mandrel 3. A ball receiving portion 73 is provided at a position corresponding to the ball hole 53 opening of the fitting groove 52 of the base 71 of the segment 7. The outer surface of this segment 7 has a shape corresponding to the ball rolling groove of the product,
The segment 7 is inserted into the inner surface portion of the preformed material A with the inner surface 72 in contact with the prismatic surface of the mandrel 3, and the rolling groove is formed in the inner surface portion by ironing.

Further, as shown in FIG.
Is inserted and the opening of the ball hole 53 and the segment 7
The ball 10 is provided between the ball receiving portion 73 and the ball receiving portion 73 in a state of being biased by the spring 9, and the ball 10 serves as a rotation fulcrum of the segment 7. Incidentally, the ball hole 53, the release hole 54, the spring 9, and the ball 10 form a ball hinge mechanism. Further, a cutout portion 74 is formed in the center portion of the inner side surface 72 of the segment 7, and the cutout portion 74 is formed in the lower die 5 as shown in FIG.
It is formed so as to contact the tip of the mandrel 3 by the sliding displacement of the mandrel to the tip side of the mandrel to permit the inward rotation of the segment 7 and to reduce the diameter of the segment 7.

The biasing spring 8 includes a lower die 5, a segment holding ring 6,
The segment 7 is interposed between the lower die 5 and the lower die main body 2 so as to soften the impact when the segment 7 slides up and down.

On the other hand, the upper die 1 has a port 11 as a guide for the work ironing.
Is provided with a die 12 having an expanded hole shape and an inner surface shape corresponding to the outer surface of the product, and a knockout pin 13 for extracting the processed product from the die 11.

Hereinafter, the molding operation with the above configuration will be described in order.

First, in the state before processing shown in the left half of FIG. 1, the lower die 5, the segment holding ring 6, and the segment 7 are positioned toward the base end side of the mandrel 3 against the biasing force of the biasing spring 8 due to their own weight. Therefore, in the segment 7, the upper part of the inner side surface 72 of the segment 7 is in contact with the prismatic surface of the mandrel 3 and is in an upright state. Then, the preformed material A is placed on the lower mold 2 so that the segment 7 is inserted into the inner surface of the preformed material A and set.

Thereafter, the press die (not shown) is lowered to lower the upper die 1 to the state shown in the right half of FIG. 1 and the working operation is completed. That is, at this time, the preformed material A is ironed by the die 12 on the outer peripheral surface, and at the same time, is ironed by the segment 7 on the inner surface to form the desired shape B. And product B after the above ironing
Is separated from the lower mold 2, and this state is shown in FIG.
In the state shown in FIG. 2, the product B cannot be extracted because it is molded along the inner surface of the die 12 and the outer surface of the mandrel 3 segment 7. In this state, when the press ram (not shown) is raised to raise the upper die 1, the product B, the lower die 5, the segment holding ring 6, and the segment are integrally raised together with the upper die 1. In this case, the outer peripheral surface of the mandrel 3, the inner surface 72 of the segment 7, and the lower die 5
The flange 51 and the side surface of the space 41 of the lower mold body 4 slide, respectively, and the state shown in FIG. 5 is reached. In this state, the flange 51 of the lower die 5 comes into contact with the stopper surface 42 of the lower die body 4, and the lower die 5, the segment holding ring 6, and the segment 7 are prevented from rising. At this time, the cutout portion 74 of the segment 7 is located at a position beyond the upper end of the tip end 32 of the mandrel 3, and the upper die 1 is further raised, so that the segment 7 is as deep as the cutout portion 74. The notch 74 contacts the upper end of the mandrel 3 by rotating inward. For this reason, the diameter of the upper half portion of the segment 7 is reduced, and the segment 7 bypasses the side opening (the recessed portion of the opening) of the product B, and the segment 7 and the product B are separated from each other. When the segment 7 and the product B are separated, the lower die 5, the segment holding ring 6, and the segment 7 descend by their own weight and return to the state shown in the left half of FIG. On the other hand, the product B further rises together with the upper die 1, but is pushed out of the upper die 1 by the knockout pin 13 which descends after the upper die 1 has finished ascending.

Further, according to the above configuration, the release hole provided in the lower die 5
By inserting a small pin or the like from 54 and pushing the ball 10 into the ball hole 53 against the biasing force of the spring 9, the engagement between the ball 10 and the ball receiving portion 73 of the segment 7 is released. The segment can be removed from the lower die 5. In this state, another segment 7 can be newly fitted into the fitting groove 52 of the lower die 5 and the pin can be removed to easily replace the segment 7. Is something that can be done.

According to the above embodiment, the ball is inserted by inserting the pin into the release hole 54.
Since the segment 7 can be easily attached / detached and replaced by pushing 10, the maintenance work of the device can be facilitated and the maintenance time can be reduced.

Further, the segment 7 is fitted in the fitting groove 52 of the lower die 5 and is rotatably held by the ball hinge mechanism, and a cutout portion is formed on its inner surface to allow the same rotational movement.
Since 74 is provided, it is possible to reduce the manufacturing cost and running cost by downsizing the segment that requires the most complicated processing. Also, since the segment support position is located as close to the product processing surface as possible, the support position The effect of the error of 1) on the product is reduced, and the dimensional accuracy of the molded product can be easily ensured.

Further, since the mandrel 6 is formed in a hexagonal prism shape and the inner surface of the segment 7 is brought into contact with the prismatic surface to ensure dimensional accuracy, the dimensional accuracy of the product is excellent and the mandrel 6 can be easily processed. The effect that the device can be manufactured at low cost is achieved.

The present invention is not limited to the above-described embodiment, and an inverted arrangement as shown in FIG. 6 may be used. In this case, instead of the spring 8, the lower die 5 is biased upward. It is necessary to provide the spring 14 that operates.

Needless to say, various modifications can be made without departing from the scope of the invention.

〔The invention's effect〕

As described above in detail with reference to the embodiments, according to the present invention, the ball hinge mechanism makes it possible to attach / detach and replace the segments extremely easily, which facilitates the maintenance work of the apparatus.

In addition, the size of the segment is greatly reduced compared to conventional products, and the manufacturing cost and running cost of the segment are reduced.

Further, since a rod-shaped mandrel whose tip portion is formed in a uniform distribution prismatic shape is used, there is an effect that machining can be performed at a lower cost than a conventional mandrel.

In addition, the segment whose rotation is allowed by the notch is held by the segment holding member by the ball hinge mechanism, which makes it easier to shift the segment support point closer to the mandrel than before, and at the same time the inner surface of the segment. Since the dimensional accuracy is ensured by making contact with the prismatic surface of the mandrel, the positional deviation of each member is reduced and the dimensional accuracy of the molded product is excellent.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention, FIG. 2 is a perspective view of a lower die which is a part of a segment holding member, and FIG. 3 is a plan view showing a state in which a segment is mounted on the segment holding member. Figures 4 and 5 are the same cross-section, Figure 5 is a cross-section showing the state where the segment comes off after ironing, Figure 6 is a cross-section showing other examples, and Figure 7 is a cross-section of the preformed material. Figures and 8 are cross-sectional views of products. 1 …… Upper mold, 2 …… Lower mold 3 …… Mandrel, 4 …… Lower mold body 5 …… Lower die, 6 …… Segment retaining ring 7 …… Segment, 9 …… Spring 10… Ball, 12 …… Dice 53 ... Ball hole, 54 ... Release hole 74 ... Notch

Claims (1)

[Claims] 1. A rod-shaped mandrel whose tip portion is formed in a regular polygonal column shape, and a substantially annular shape, which is slidably fitted on the mandrel and which corresponds to each prism surface of the mandrel. And a segment holding member having a plurality of radially arranged fitting grooves, and a base portion which is fitted into the fitting grooves and extends in the axial direction of the mandrel so that the inner surface is in contact with the prismatic surface of the mandrel. A plurality of segments which are radially arranged on the outer surface of the tip of the mandrel and iron-roll a rolling groove on the inner surface of the preformed material, and the segment holding member is inclined from the side surface of the fitting groove toward the base end side. The ball hole that is bored, the ball receiving portion that is recessed in the side surface of the base of the segment corresponding to the opening of the ball hole, and the ball hole opening and the ball hole opening that is biased by the spring inserted into the ball hole. baud A ball, which is disposed between the ball and the receiving portion and serves as a rotation supporting portion of the segment, and a release hole having a diameter smaller than that of the ball, which is provided in communication from the tip end side of the segment holding member to the vicinity of the ball hole opening. When the ball hinge mechanism is provided and the segment holding member is recessed in the central portion of the inner peripheral surface of the segment and is displaced near the tip of the mandrel by the sliding displacement of the segment holding member toward the tip of the mandrel, the segment is inward of the tip of the segment. And a notch formed so as to allow the rotation of the preform and the outer peripheral portion of the preformed material in which the segment is inserted into the inner surface portion while the inner surface of the segment front portion is in contact with the tip of the mandrel. A universal joint outer ring machining device with a die for machining