JP2002331318A - Die for manufacturing belleville spring - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a die for manufacturing a coned disc spring capable of shortening working hours and reducing costs of the product since the height of the die and the punch can easily be adjustable while being installed on the press, without disconnecting the die from the press for disassembling. SOLUTION: In order to combine a die 15 into a mold, traditional metal spacer and setscrew are not used and a fundamental section 15a of the die is abutted to the slant surface 31a of a cam by providing the cam in the mold and by installing a micrometer 33 to the mold, a spindle 33a is applied to the end section of the cam, the cam is operated with the micrometer. The slant surface of the cam operates so that the die position is finely adjusted up and down. The cam is pulled back by the action of a spring 36. The space 14 is made of an elastic body like polyurethane rubber and the die is always imposed to the cam with elasticity. The punch side can also have the same structure. The operation of the micrometer enables necessary adjustments while the mold is being fixed to the press.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a press die for manufacturing a disc spring to be incorporated as a component in a tact switch or the like.

[0002]

2. Description of the Related Art FIGS. 2A and 2B are drawings of a disc spring incorporated as a component in a tact switch or the like. FIG. 2A is a plan view, and FIG. As shown in the figure, a thin metal plate is formed in a dish shape which is circular, substantially spherical and shallowly curved. When the disc spring 1 is incorporated into a switch, the disc spring 1 is placed on a circuit board on which a conductive pattern is formed, and its outer periphery contacts the first fixed contact on the circuit board. Is provided with a second fixed contact. When the vertex of the bend of the disc spring 1 is pressed down directly or through a push button or the like, when the pressing force reaches a certain level, a kind of buckling occurs, and the curvature of the central portion is rapidly reversed,
The lower surface of the apex contacts the second fixed contact of the circuit board. As a result, the first fixed contact and the second fixed contact become conductive, and a switching operation is performed.

FIG. 3 shows a state of a workpiece when such a disc spring 1 is manufactured by a progressive press die. The material is a strip 2 where a number of parts to be processed are connected as shown in FIG.
An enlarged view of a portion B surrounded by a square is shown in FIG. Strip 2
Has a reference hole 3 for feeding and positioning, and a large window (octagon here) is opened between the reference holes 3, and a disc-shaped disc spring portion 4 is formed inside the window. , And is connected to a surrounding frame portion by a connecting portion 5. The disc spring portion 4 is drawn with a die as it is to form a shallow dish, and the strip material is removed from the strip material at the cutting portion 6.

FIG. 4 is a front sectional view of a die for drawing a strip 2 into a dish shape. The upper mold and the lower mold are separated, and the lower mold is a die holder 11, a die pad 12, and a die plate 13.
The die 15 is accommodated inside the die and fixed with set screws 16. The height relationship between the upper surface of the die plate 13 and the concave surface at the upper end of the die 15 is determined by the spacer 14 of the metal ring.
The upper die accommodates a punch 21 inside the punch holder 17, the punch pad 18, and the punch plate 19, and is fixed with a set screw 22. The relationship is determined by the spacer 20 of the metal ring.

[0005] Between the upper mold and the lower mold, the band 2 shown in FIG.
Is placed and pressed by a press and squeezed, whereby the disc spring portion 4 of the strip 2 is formed into a dish shape. FIG. 5 shows such a state, in which the disc spring portion 4 of the band is sandwiched between the die 15 and the punch 21.
After this, the cutting section 6 is cut at another stage of the progressive type,
A completed disc spring 1 as shown in FIG. 2 is obtained.

[0006]

Normally, if a die is mounted on a press and a drawing process is started, a desired disc spring cannot be obtained immediately. An error occurs. That is, there are variations (thickness, hardness) of the band material as the raw material, accuracy of the press machine, set error in changing the mold, springback of the workpiece, and the like. In such a case, it is necessary to delicately change the curvature and curvature of the disc spring to achieve the intended characteristics, or to use a disc spring with a different specification and slightly different characteristics without changing the mold. There are times when you want to achieve just by adjusting the mold.

The conventional countermeasure in these cases is to change the thicknesses of the spacer 14 and the spacer 20 in FIGS. 4 and 5 so that the punch 21 and the surrounding upper die part and the die 15 and the surrounding lower die part are not changed. To adjust the height relationship, the mold is removed from the press, disassembled and the spacers 14, 2
You have to replace 0 with another one. Therefore, it takes time until the start of manufacturing, and the manufacturing cost increases. An object of the present invention is to provide a disc spring manufacturing mold capable of facilitating the adjustment of the mold and shortening the time until product delivery.

[0008]

SUMMARY OF THE INVENTION In a conventional mold, a die 15 is used.
When assembling the punch 21 with the lower die and the upper die, they are positioned by the spacers 14 and 20 and fixed by the set screws 16 and 22. In the present invention, the metal spacer and the set screw are eliminated. Instead of the set screw, the base of the die or punch is supported by a cam with a slope. Thus, the height is adjusted by moving the cam in a direction perpendicular to the axis of the die or punch and moving the root of the die or punch up or down along the slope of the cam.

It is necessary to apply force to the die or punch so that the root portion always hits the slope of the cam. For this purpose, the spacer is made of an elastic material such as urethane rubber instead of a metal ring. Further, a micrometer is arranged on the mold, the tip of the spindle is applied to the cam, and the cam is moved by feeding the screw of the micrometer. From the relationship between the pitch of the screw of the micrometer and the angle of the slope of the cam, the amount by which the die and the punch move up and down with one graduation of the micrometer can be accurately defined. In this way, the height of the die and the punch is adjusted only by operating the micrometer, and the setup of the press working becomes more efficient.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view of a mold according to an embodiment of the present invention. For simplicity, the structure of a portion related to the present invention is shown. 4 and the like, the die holder 11, the die pad 12, the die plate 13 and the like constitute a lower die, and the die 1
5 are accommodated. Characteristically, the cam 31 is arranged by providing a space in the shape of a horizontal hole in the die pad 12, so that the cam 3
1 is slidable left and right on the die holder 11, and has a slope 31a on the upper side. The die 15 also has the lower surface of the root portion 15a formed as a slope, and rides on the slope 31a of the cam 31.

The holding portion 3 is provided on the upper surface of the die holder 11.
2, and a micrometer 33 is fixed thereto.
The tip of the spindle 33a of the micrometer 33 is inserted into the sunken portion 31b on the right end surface of the cam 31 and is brought into contact with the bottom surface. Also, a pin 34 is set up on the front side of the cam 31 and a pin 35 is set up on the upper surface of the die holder 11, and a spring 36 is hung between the pins 34 to pull the cam to the right.

With this structure, when the knob of the micrometer 33 is turned to cause the spindle 33a to protrude to the left,
The right end of the cam 31 is pushed to move to the left, and the root 15a of the die 15 is pushed by the slope 31a of the cam 31 and rises.
However, due to the action of the slope 31a, the amount of rise of the die 15 is smaller than the amount of protrusion of the spindle 33a of the micrometer 33,
It will be greatly reduced. If the micrometer 33 is turned in the reverse direction to retract the spindle 33a to the right, the cam 31 moves to the right without leaving the spindle 33a by the force of the spring 36, and the die 15 descends along the slope 31a.

In order for the die 15 to move up and down closely following the movement of the cam 31, it is necessary to apply a downward force to the die 15 so that the root 15a is always pressed against the slope 31a. For this purpose, for example, a coil spring having a large deformation amount is accommodated in the place of the spacer 14, and it is satisfactory if the root portion 15a of the die 15 can be pushed down. However, usually, there is no space for inserting the coil spring in this portion. I can't get it. Since the movement amount required for the die 15 is originally not a large value, a wave washer may be used instead of a coil spring. However, in the present invention, a spacer 14 made of an elastic material capable of expanding and contracting in volume is used in this portion. As the elastic material, for example, urethane rubber is preferable, and the object can be achieved by forming the spacer 14 from urethane rubber and applying a preload thereto to incorporate the spacer.

FIG. 1 shows only a part of the punch plate 19, the punch 21 and the stripper 23 for the upper die, but the upper die is also provided with a mechanism similar to that of the lower die for adjusting the height of the punch 21. It goes without saying that you can do it.

As described above, while the cam 31 is pushed by the micrometer 33 and pulled back by the spring 36, the movement of pushing the cam 31 by the micrometer 33 is
It is more reliable than the movement of pulling back by the spring 36, and in the actual adjustment work, the height of the cam 31 is not determined in the return stroke of the cam 31 by relying on the spring 36.
And the cam 31 is returned, and the cam 31 is pushed again by the micrometer 33 by an appropriate amount to determine the height.
However, this is a work problem.

[0016]

According to the present invention, it is not necessary to remove the mold from the press and disassemble it as in the prior art, and the height of the punch and the die can be easily adjusted while the mold is still attached to the press. In addition, since the micrometer is used, the amount of movement is accurately determined, and since the movement is reduced by a cam with a slope, 1/1
Fine adjustment in units of 000 mm is possible. This allows fine adjustment of spring characteristics and improves quality,
The working time is shortened and the product cost is reduced.

[Brief description of the drawings]

FIG. 1 is a partial sectional view of a mold according to the present invention.

2A is a plan view of the disc spring, and FIG. 2B is a sectional view taken along line BB of FIG. 2A.

FIG. 3A is a plan view of a strip in a state where a disc spring is processed,
(B) is a partially enlarged view of (A).

FIG. 4 is a sectional view of a conventional mold.

FIG. 5 is a cross-sectional view of the mold of FIG. 4 during operation.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 disc spring 2 band material 4 disc spring portion 11 die holder 12 die pad 13 die plate 14, 20 spacer 15 die 16, 22 set screw 17 punch holder 18 punch pad 19 punch plate 21 punch 31 cam 31 a slope 31 holding portion 33 micrometer 33a spindle 36 spring

Claims (3)

[Claims] 1. A die having a punch and a die for producing a disc spring by drawing, wherein a cam having an inclined surface is provided so as to be movable in a direction substantially perpendicular to the axis of the punch or the die. Place the micrometer on the slope of the cam and attach the micrometer with the spindle on the cam so that the movement of the micrometer spindle pushes and moves the cam, the punch or die root and the inner surface of the mold A die for manufacturing a disc spring, wherein a spacer made of an elastic material is arranged between the punches and a punch or a die is pressed against the cam by the elasticity of the spacer. 2. The disc spring manufacturing die according to claim 1, wherein the elastic material of the spacer is urethane rubber. 3. The disk spring manufacturing die according to claim 1, further comprising a spring for urging the cam to press the cam against a spindle of the micrometer.