JPH0698451B2 - Method of aligning work piece and die in cold plastic working - Google Patents

Description

Detailed Description of the Invention [Industrial applications]

The present invention relates to a method for aligning a workpiece and a die in cold plastic working of a spline piece in a gear clutch of a gear transmission, for example, in the final reverse taper forming step, the workpiece has a chamfer upward. Regarding phase matching when mounted.

[Prior art]

Regarding this type of cold plastic working, for example, Japanese Patent Publication No.
As shown in Japanese Patent No. 4696, a spline tooth having a complicated shape is formed by processing a work piece through a plurality of steps. Here, finally in some steps, there is a step of forming an inverse taper on both sides of the spline tooth and the tooth groove. In the reverse taper forming process,
Set the workpiece with the chamfer and straight spline teeth set in the die with the chamfer facing upward, and press the workpiece down with a punch in this state, so that the spline tooth below the chamfer is pressed by the die. It is designed to form an inverse taper. Therefore, in the preceding stage of this process, the spline teeth of the workpiece are placed in the recesses of the mold, and the tooth grooves are placed in the projections of the mold with the chamfer facing upward, and the peripheral phase is aligned. Need to be set.

[Problems to be Solved by the Invention]

Therefore, conventionally, it has been proposed that the work piece set in the inverse taper forming step is performed manually by an operator as shown in JP-A-53-64897, for example. Inability to perform automated processing. On the other hand, for example, in Japanese Examined Patent Publication No. 52-35337, there is shown a positioning method in the case of setting the workpiece with the chamfer facing downward in the process of forming the spline teeth, and the auxiliary punch is cut from the tip blade to the workpiece. Has been proposed for aligning the work piece while forcibly rotating the work piece. However, according to this method, there is a problem that the tip of the chamfer may be damaged, and the auxiliary punch and the work piece need to be properly joined before alignment and separated after the alignment. In view of the above-mentioned problems in the prior art, the present invention is an object to be phased in the workpiece before the inverse taper forming step is an object to be processed in cold plastic working which is automated so that an unreasonable force does not act on the object. It is an object of the present invention to provide a method of aligning a mold with a die.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, the present invention is to form a spline tooth on the outer periphery through a required cold plastic working process from a ring-shaped material, and a mountain-shaped chamfer formed at the end of the spline tooth. In the preceding stage of the step of forming a workpiece and setting the chamfer upward in the mold in the subsequent forming step to form the inverse taper surface on both sides of the tooth, In the method of performing the phase alignment between the spline teeth and the mold, the upper mold and the lower mold are opposed to each other, and the lower mold has the workpiece to be processed through the protrusion protruding on the plate and the chamfer upward. It is rotatably mounted in the above state, facing the upper side of the work piece, and provided with a hollow guide urged downward by a spring in the upper die so as to be movable up and down while being prevented from rotating, A splice of the work piece is formed on the lower circumference of the guide. Forming a mountain-shaped chamfer ring that fits into the tooth groove, and the chamfer ring elastically abuts the upward chamfer of the workpiece due to the lowering of the guide to rotate the workpiece due to the interference of the tapered surface, It is characterized in that the chamfering is fitted in the tooth space so as to match the phase.

[Action]

According to the above configuration, the work piece is rotatably placed on the lower plate through the protrusions with the chamfer facing upward, and the chamfer facing upward of the work piece is used to First, the chamfering is lightly contacted with a tapered surface, and then the work is rotated by the component force in the circumferential direction.Therefore, it is not necessary to apply an unreasonable force to the work or to consider escape. preferable. In addition, since no forcible turning means is provided, it does not damage the work piece,
Die failure and maintenance can be reduced.

【Example】

Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings. In FIG. 1, an example of the processing state of the workpiece in each step will be described. Reference numeral W is the workpiece, and initially has a ring shape having substantially the same diameter. Then, the workpiece W is extruded in step I to form the taper portion 1a and the spline portion 1b in steps, and the chamfer is formed on the outer periphery of the spline 1b.
A straight spline tooth 2 having a 2a and a tooth groove 3 are simultaneously formed, and further a front bottom face 3a is formed in the tooth groove 3, and a pushing wall 4 bulging outward in the radial direction is formed at the rear portion of the spline tooth 2. Have. Next, in step II, the pushing wall of the tooth groove portion of the workpiece W is punched and removed by the punching blade. Then, in the reverse taper molding of the process III, the workpiece W is set in the mold with the chamfer 2a facing upward, and the chamfer 2a
Reverse taper surfaces 2b are formed on both sides of the lower spline tooth 2 and a rear descending bottom surface 3b is formed behind the chamfer 2a of the tooth groove 3,
It will be a spline piece product. Therefore, the workpiece W is formed in the preceding stage of the reverse taper forming step III.
The phase matching device of this case will be described with reference to FIGS. 2 and 3. In the figure, reference numeral 10 is an upper die, 11 is a cylindrical pad which is attached to the upper die 10 by being locked by a key 24, and a hollow guide 13 having a stopper 12 inside the pad 11.
However, the outer vertical groove 14 is loosely fitted to the pin 15 of the pad 11 and is inserted so as to be vertically movable while being prevented from rotating, and the spring 16 is biased between the upper die 10 and the guide 13. Guide 13
A chamfer ring 17 that fits with the tooth groove 3 of the workpiece W is formed around the lower end of the workpiece as shown in FIG.
A plate 19 having a protrusion 18 slidably fitted into the shaft hole 5 of the workpiece W is fixed under the guide 13. Next, the operation of the phase matching dedicated apparatus thus configured will be described with reference to FIG. First, putt with upper mold 10
11 and the guide 13 move upward and stand by, and the workpiece W conveyed to the protrusion 18 of the plate 19 in this state is randomly fitted with the chamfer 2a facing upward. At this time, the guide 13 pops out to the bottom and the spring 16
Is weak, and when the upper die 10 is lowered after setting the workpiece W as described above, the guide 13 is also lowered as it is. Therefore, when the chamfer ring 17 of the guide 13 and the tooth groove 3 of the workpiece W do not coincide with each other, the chamfer ring 17 and the chamfer 2a of the workpiece W are tapered surfaces and are light as shown in FIG. 4 (a). Hit After that, as the upper mold 10 descends,
The guide 13 sequentially enters the pad 11, and the force of the spring 16 increases, whereby a component force in the circumferential direction acts from the chamfer ring 17 to the chamfer 2a. When the predetermined component force is reached, the workpiece W rotates, and the chamfer ring 17 is fitted into the tooth groove 3 as shown in FIG. 4 (b), and the phase matching is completed. Here, if the guide 13 is preliminarily positioned with respect to the mold of the reverse taper molding apparatus, the workpiece W can be conveyed in the state where the above-mentioned phase alignment is performed, so that the reverse taper molding apparatus can be accurately matched. become. Referring to FIG. 5, the case where the phase matching means is assembled to the inverse taper molding device will be described. The upper mold 10 is provided with the pad 11, the guide 13 and the spring 16 in the same manner as described above. The punch 20 is attached to the upper mold 10. A hollow lower mold 22 having an inverse taper molding concave portion 21 is coaxially installed below the guide 13, and a protrusion 18 is provided inside the lower mold 22.
A counter punch 23 having a is inserted so as to be vertically movable. Therefore, in this embodiment, when the workpiece W is set on the projection 18 of the counter punch 23 and the upper die 10 is lowered, the guide 13 is projected prior to the punch 20, so that the chamfering of the guide 13 is first performed. The workpiece W is held in the same phase matching state as described above while being rotated by the work piece 17, and after the punch 20 hits the work piece W, the work piece W comes out of the chamfering 17 and descends as it is. Lower mold
It is pushed into 22 and the reverse taper is formed. In this way, the workpiece W and the lower mold 22 are automatically phase-matched before the reverse taper molding.

【The invention's effect】

As is apparent from the above description, according to the phasing method of the present invention, the workpiece and the mold are automatically phased in the preceding stage of the inverse taper molding step, so that manual phasing is unnecessary. Therefore, the work efficiency can be improved. It is also possible to use a chamfer facing upward on the work piece, and first contact the chamfering with a lightly tapered surface, and then rotate the work piece with a circumferential component force, which is impossible for the work piece. Since it is not necessary to take into consideration any force or escape, it is preferable. When the phase matching means is assembled to the inverse taper molding device as in the embodiment of FIG. And so on, the accuracy is improved.

[Brief description of drawings]

FIG. 1 is a diagram showing each step of cold plastic working to which the present invention is applied, FIG. 2 is a sectional view showing a dedicated device for carrying out the method of the present invention, FIG. 3 is a partial sectional view, 4 (a), (b)
FIG. 5 is a diagram showing a phase matching operation, and FIG. 5 is a sectional view showing an inverse taper forming device with a phase matching means as another embodiment of the method of the present invention. W ... Workpiece, 2 ... Spline tooth, 2a ... Chamfer, 13 ... Guide, 17 ... Chamfering, 18 ... Protrusion.

Claims (1)

[Claims] 1. A work piece having a spline tooth and a mountain-shaped chamfer formed at an end portion of the spline tooth is formed from an annular material through a required cold plastic working step. In the preceding stage of the step of setting the chamfer upward in the mold in the next forming step to form the inverse taper surface on both sides of the tooth, the spline teeth of the workpiece and the die are formed. In the method for performing the phase matching, the upper mold and the lower mold are opposed to each other, and the lower mold is rotatably supported with the chamfer facing upward through the protrusion protruding on the plate. A hollow guide is placed on the upper die facing the above-mentioned work piece and is urged downward by a spring so that the hollow guide can be moved up and down. Chevron that fits with the spline tooth groove of the workpiece Forming a Chamfering of chamfering by the lowering of the guide,
Cold plasticity characterized by elastically abutting the upward chamfer of the work piece and rotating the work piece by interference of the tapered surface so that the chamfer ring fits into the tooth groove and the phases are aligned. Method for aligning the phase of the work piece and the mold in machining.