JPH0128922Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a spline forming press device for forming splines on the outer periphery of a press work.

(Prior Art) Some automatic transmission parts for automobiles have tooth-shaped grooves or splines formed along the axial direction on the outer periphery of the part. The conventional method for forming this spline is, for example, as shown in Japanese Utility Model Application Publication No. 59-89339, by ironing, in which a workpiece is passed through a die having a circular arrangement of rollers.

(Problem to be solved by the invention) However, in this iron forming, the relative sliding speed of the workpiece with respect to the die is high, so it is easy to cause seizure between the die and the workpiece, and furthermore, the surface of the workpiece is scratched. This problem not only impairs the quality of the spline molded product but also shortens the life of the die.

In addition, as shown in Japanese Utility Model Application Publication No. 53-93538, a plurality of dies are arranged radially on the base so as to correspond to the spline forming part of the press work, and each of the dies is moved forward and backward with respect to the press work. It has been proposed that the spline is formed by moving the die blade to contact the entire width of the press working width. However, with this method, the spline is formed by bringing the die into contact with the entire width of the press by moving the die in one direction, which requires a large load to be input to the die, resulting in an increase in the size of the device. There is.

The present invention was developed in view of the above-mentioned problems, such as scratches on press work,
The purpose of the present invention is to obtain a spline forming press device that can reliably perform spline forming without causing seizure between the press work and the die or punch and without inputting a large load to the die. It is.

(Means for Solving the Problem) In order to achieve the above object, the solving means of the present invention is directed to a press device that forms a spline on the outer periphery of a press work. A plurality of dies are arranged radially on the base so as to correspond to the spline forming portion of the press work. The die is tilted and supported with respect to the base so as to be able to swing up and down using the outer end as a fulcrum, and the inner end of the die is formed in an arc shape around the rotation point of the outer end. An arcuate portion is provided, and the arcuate portion has a convex cross-sectional shape in a direction perpendicular to the tangential direction thereof, corresponding to the concave portion of the spline. A workpiece mounting table on which a press work is placed is provided on the base so as to be movable up and down. A punch mount is provided above the workpiece mounting table, and is equipped with a punch having a tooth pattern corresponding to a spline shape formed on its outer periphery, and a die pressing member for pressing each of the dies. The workpiece mounting table is lowered by the downward movement of the table, and the die is rotated downward while the arcuate portion at the inner end is brought into contact with the press workpiece.

(Function) As a result, in the present invention, when the press work is placed on the work mounting table and the punch mount is lowered, the punch comes into contact with the press work and holds it, and the die pressing members also Contact with the top surface of the die. When the punch mounting base is further lowered from this state, the punch pushes down the press work and the work mounting base, and the die is also pushed down by the die pressing member, and the die works on the press work with its outer end as a fulcrum. First, the lower end of the arc-shaped part contacts the outer periphery of the press work, and then the outer periphery of the press work is sequentially pressed from the lower end of the arc-shaped part to the upper end. Since it fits into the tooth pattern of the punch, the outer circumferential portion of the press work is compressed between the tooth pattern and the circular arc portion, and a spline is formed around the entire outer circumferential portion.

In this case, while moving the die and press workpiece in the same direction (downward), a part of the circular arc at the inner end of the die is brought into contact with the press workpiece to locally form a spline recess, so input from the die is required. Since the load can always be concentrated on the contact portion at the inner end of the die, spline forming can be performed reliably without inputting a large load to the die.

(Example) Hereinafter, an example of the present invention will be described based on the drawings.

As shown in FIGS. 1 and 2, the press device 1 for spline forming includes an upper mold 2 and a lower mold 3,
A polygonal 6 (octagonal in this example) recess 4a is formed in the center of the base 4 of the lower mold 3. In the recess 4a, there are 8 dies 7, 7, .
The dice are arranged radially such that the inner end of each die faces the center of the octagon. The outer ends 7b, 7b... of the dice are projections 5 formed on the inner ends of the presser plates 5, 5... fixed to the outer peripheral part 4b of the base 4.
a, 5a, . . . and is supported so as to be able to swing up and down.

The dies 7, 7... have a convex shape corresponding to the concave portion of the spline S of the press work 8 at their inner ends, and are formed in an arc shape in the vertical direction centering on the fulcrum A of the die outer ends 7b, 7b... arc-shaped part 7
It is equipped with a, 7a... That is, the arcuate portion 7a has a convex cross-sectional shape in a direction perpendicular to the tangential direction thereof, corresponding to the concave portion of the spline S. In addition, the upper surface 7c of the dice 7, 7,
7c... is a die pressing member 18, 18... which will be described later.
It is formed into a wave shape so that it comes into contact with the and,
These dies 7, 7... are kept at a predetermined angle α when the upper die 2 is not acted upon by resilient members 10, 10... interposed between the dies 7 and the base 4. The outer end portions 7b, 7b, .

On the other hand, a guide bar 12 is fixed to the bottom of the workpiece mounting table 11, and the guide bar 12 is fitted into a guide hole 13 formed in the center of the recess 4a so as to be slidable up and down. Further, the workpiece mounting table 11 is always urged upward with respect to the base 4 by an elastic member 15 fitted to the guide bar 12, and maintains a predetermined height h when the upper die 2 is not acting. It is supported as such.

The punch mount 16 of the upper mold 2 is movable up and down by a press means (not shown), and a punch 17 is attached to the bottom of the punch mount 16 facing the workpiece mounting table 11. The punch 17
There is a tooth pattern 1 corresponding to the shape of the spline S on the outer periphery of the
7a is formed. In addition, the punch mounting base 16
On the outer circumferential side of the punch 17, die pressing members 18, 18, .

Next, a method of forming a spline on a press work using the apparatus of the above embodiment will be explained in order.

Press work 8 previously formed into a cylindrical shape with a bottom
is placed on the workpiece mounting table 11, and when the punch mounting table 16 is lowered by a press means (not shown), the punch 17 comes into contact with and holds the presswork 8, and the die pressing member 18, 18
...also the top surface 7c of each die 7, 7...
7c... (see Figure 1). When the punch mounting base 16 is further lowered from this state, the punch 17 pushes down the press work 8 and the work mounting base 11 against the elastic member 15, and the dies 7, 7... are also pushed down by the die pressing member 18. ,1
8... is pressed down against the resilient members 10, 10..., and the dice 7, 7... are pushed down at the fulcrum A.
The arc-shaped portion 7
The lower ends of a, 7a, . 17a, the outer periphery of the press work 8 is compressed between the tooth pattern 17a and the arcuate portions 7a, 7a, . . . , and a spline S is formed around the entire outer periphery.

After forming the spline S on the press work 8, when the punch mounting base 16 is raised by the press means, the dies 7, 7... and the work mounting base 11 are set at a predetermined angle α and a predetermined height as shown in FIG. Since each return is made up to h, the next press work 8 can be processed.

In this case, while moving the die 7 and the press work 8 in the same direction (downward), a part of the circular arc portion 7a at the inner end of the die 7 is brought into contact with the press work 8 to locally form a concave portion of the spline S. Therefore, the input load from the die 7 can always be concentrated on the abutting portion of the inner end of the die 7, so that spline forming can be performed reliably without inputting a large load to the die 7.

(Effect of the invention) As described above, according to the invention, by moving the punch mount downward, the workpiece mounting table is lowered and the die is brought into contact with the press workpiece with its inner arcuate part. The spline is formed by pressing the outer periphery of the press workpiece on the workpiece mounting table with the tooth pattern formed on the punch and the circular arc portion of the die.
The relative sliding speed between the press work and the die is reduced, reducing seizure between the two and the occurrence of scratches on the press work surface, which not only improves the quality of the product after spline forming, but also extends the life of the die and punch. do. Furthermore, while moving the die and the press workpiece downward, a part of the circular arc of the die is brought into contact with the press workpiece to form a localized spline recess, so that the input load from the die is always kept in contact with the inner end of the die. This has the excellent effect of being able to concentrate only on the contact portion, ensuring spline forming without inputting a large load to the die, and making it possible to downsize the device.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a longitudinal cross-sectional view of a press device for spline forming, showing the state before forming splines, FIG. 2 is a plan view showing a part of the device, and FIG. is a longitudinal sectional view of the same device, showing the state when spline formation is completed. DESCRIPTION OF SYMBOLS 1... Press device for spline forming, 4... Base, 7... Die, 7a... Arc-shaped part, 7b...
Die outer end, 8...Press work, 10...Resilient member, 11...Work mounting table, 15...Elastic member, 16...Punch mounting base, 17...Punch, 1
8...Dice pressing member, A...Fully point, S...Spline.

Claims (1)

[Claims for Utility Model Registration] A press device for forming splines on the outer periphery of a press work, comprising a plurality of dies arranged radially on a base so as to correspond to the spline forming portion of the press work, The die is tilted and supported with respect to the base so that it can swing up and down with the outer end as a fulcrum, and the inner end of the die has an arc shape formed around the rotation point of the outer end. The arcuate cross section in the direction perpendicular to the connection direction has a convex shape corresponding to the concave portion of the spline, and the workpiece mounting table on which the press work is placed is movable up and down on the base. A punch mount is provided above the workpiece mounting table, and is provided with a punch having a tooth pattern corresponding to a spline shape formed on the outer periphery, and a die pressing member for pressing each of the dies. For spline forming, characterized in that the work mounting table is lowered by the downward movement of the punch mount, and the die is rotated downward while the arcuate portion at the inner end is in contact with the press work. Press equipment.