JPS60166128A - Method of shaving work - Google Patents

Abstract

PURPOSE:To make press capacity small by laminating a front stage die having larger die hole than the die hole of rear stage die on the rear stage die having die hole of the size of outer diameter of a product, and shaving with a punch having outer diameter of the size of rear stage die hole. CONSTITUTION:A blank 20 is blanked by a die hole of inner diameter Da which is larger than outer diameter D of a product by shaving allowance. The die hole 10A of the rear stage die 10 is equal to outer diameter of the product, and the size Dc of the die hole 9A of the rear stage die 9 in its upper part is made larger than the die hole 10A and desirably smaller than outer diameter Da of the blank 20. The size of outer diameter of the punch 11 is a little smaller than the die hole 10A. By making shaving lowering the shaving punch 11 and dividing into two by die holes 9A and 10A, the large breaking face is removed by one process of a press of small capacity, and the cost is lowered by miniaturizing the die.

Description

[Detailed description of the invention] (a) Technical field of the invention The present invention relates to a shaving method.

(b) Background of the technology When a punch and a die are placed in a press and a plate is punched out into a product with a desired external shape, the outer dimensions of the cut end of the product are the same as those of the die. A flat sheared surface is formed that is equal to the die hole, and a rough fractured surface that is smaller than the dimensions of the die hole is formed following the sheared surface on the punching die bunch side. Therefore, for products that require a flat outer circumferential cut and high precision in external dimensions, punch out the plate material.
It is common to process blanks with shaving and then shave the blanks.

(C) Prior Art and Problems A conventional shaving method will be explained with reference to FIGS. 1 to 3. Figure 1 is a cross-sectional view during blank processing, Figure 2
The figure is a cross-sectional view during shaving processing, and FIG. 3 is a cross-sectional view of the product.

In FIG. 1, the punching die 5 has a die hole 5A having an internal dimension Da larger than the external dimension of the product by the amount of shaving.
is provided. The outer shape of the punch 4 is the die hole 5.
It is formed to have an external dimension Db smaller than A by a clearance. This clearance is selected depending on the material of the plate 1, its thickness, and the processing accuracy required for the product.

When the plate material 1 is placed on the upper surface of such a punching die 5 and pressed by the punch 4, a blank 2 having a size approximately equal to the inner dimension of the gouging hole 5A is obtained.

The lower sheared surface 2a of the cut of this blank 2 is the die hole 5A.
It is flat and approximately equal in dimension to . However, at the upper part of the sheared surface 2a, a crank is inserted from the edge of the punch 4, forming a rough fractured surface 2b.

The dimensions of the upper end surface of the fractured surface 2b are approximately equal to the external dimensions of the punch 4.

In order to make such a blank 2 into a product 3 having the desired external dimensions shown in FIG. 3, it is shaved as shown in FIG.

In Figure 2, the shaving die is provided with a die hole 7A having an internal dimension equal to the external dimension of the product. The outer dimensions of the shaving punch 6 are approximately D, which is very slightly smaller than the die hole 7A.

When the blank 2 is placed on the top surface of the shaving die in alignment with the die hole 7A and pressed with the shaving punch 6, the cut of the blank 2 is shaved to become a flat and smooth cut, and the inner shape of the die hole 7A is A product 3 with dimensions equal to the dimensions is obtained.

However, if the plate material 1 is relatively thick, or if it is made of brittle material, or if the product 3 has a complicated external shape, such as a gear, the fracture surface 2b will become large, as shown in Fig. 3. A fractured surface 3b often remains on the upper surface of the product 3.

In order to also remove this fractured surface 3b, it is necessary to process the blank into a blank with a large degree of shaving. However, there is a limit to the amount of shaving that can be achieved in one shaving session, so either shave in two steps or
Alternatively, there is a problem in that the remaining fractured surface 3b must be removed by hand finishing or other machining means.

(d) Object of the Invention In view of the above-mentioned conventional problems, it is an object of the present invention to provide a shaving method capable of removing the fractured surface by -times of pressing strokes.

(e) Structure of the Invention In order to achieve this object, the present invention provides a rear die having a die hole equal to the external dimensions of the product, and a die hole desirably larger than the die hole of the rear die in the upper part of the rear die. a shaving die formed by laminating and combining pre-stage guides having
There is a method in which a shaving punch having an outer diameter equal to the size of the gouge hole of the latter die is used, and the punched blank having a desired shaving pattern is shaved in one stroke of the shaving punch.

(f) Embodiments of the Invention The present invention will be described in detail below with reference to illustrated embodiments.

FIG. 4 is a front view of a shaving mold according to an embodiment of the present invention, and FIGS. 5A and 5B are cross-sectional views during shaving processing, respectively.

In FIG. 4, reference numeral 20 denotes a blank punched by a punching die provided with a die hole having an internal dimension Da larger than the external dimension of the product by the amount of shaving.

On the upper surface of the bolster 8, which is the lower part of the shaving mold,
A shaving goo consisting of a rear die 10 and a front die 9 stacked on top of the rear die 1o is attached. The rear die 1o is provided with a die hole 10A having an outer dimension of 3° of the product. Further, the front die 9 stacked and mounted on the upper part of the rear die lo has a die hole 9A having an inner dimension Dc larger than the die hole 1°A of the rear die 1o and desirably smaller than the outer dimension Da of the blank 20. is provided. Note that the axes of the die hole 10A and the die hole 9A are aligned.

A shaving punch 11 is fixed to the center of the punch holder 12 so as to protrude vertically downward. The external dimensions of the shaving punch 11 are the die hole 1 of the rear die 10.
The outer dimensions are formed into a shape D which is very slightly smaller than 0A. A guide hole provided in the punch holder 12 is fitted into a guide bar 13 set up on the bolster 8, so that the shaving punch 11 is matched to the shaving die.

Such a shaving mold is inserted into a press (not shown). The blank 2o is guided by a not-illustrated guide plate mounted on the upper surface of the pre-stage die 9, and is aligned with the die hole 9A.

In FIG. 5(a), the shaving punch 11 descends, presses the top surface of the blank 20, forces the blank 20 into the die hole 9A of the pre-stage die 9, and shaves the punched cut on the outer peripheral surface of the blank 20. are doing. Approximately half of the blank 20 is shaved by this die hole 9A.

Further, the shaving bunch 11 descends and the blank 2 is removed.
When the blank 20 is completely pushed into the die hole 9A, the lower part of the blank 20 that has been roughly shaved by the front die 9 is pushed into the die hole 10A of the rear tie 10 as shown in FIG. 5(B). This allows the remaining shaving to be performed by the subsequent die l.
The sheared surfaces and fractured surfaces formed by the stamping process are completely removed by shaving with O. The product 30 obtained by shaving in this manner has a smooth, vertical, flat outer peripheral surface, and has a desired zero dimension, which is equal to the die hole 10A of the subsequent die IO.

Although this is a large amount of shaving, the present invention divides this shaving into two stages and performs shaving, so the shaving power is reduced by almost half, there is no need for a large-capacity press, and the strength is the same as before. A shaving type with a .

(g) Detailed Description of the Invention As described above, the present invention has practical advantages such as being able to remove a large fractured surface with one press stroke of a small-capacity press, and the shaving mold being small and low cost. This is an extremely effective shaving method.

[Brief explanation of the drawing]

Fig. 1 is a sectional view during blank processing, Fig. 2 is a sectional view during conventional shaving processing, Fig. 3 is a sectional view of a conventional product, and Fig. 4 is a shaving mold according to an embodiment of the present invention. 5A and 5B are cross-sectional views during shaving processing, respectively. In the figure, 1 is a plate material, 2.20 is a blank, 2a is a sheared surface, 2.
b, 3b are fractured surfaces, 3, 30 are products, 4 is a punch, 5 is a die, 5A, 7A. 9A and IOA are die holes, 6.11 is a shaving punch, 7 is a shaving die, 8 is a bolster, 19 is a front die, 10 is a rear die, 12 is a punch holder, and 13 is a guide bar. Thing 1 @ Tower? Drunkness■

Claims (1)

[Claims] A shaving gou is formed by laminating and combining a rear stage die having a die hole equal to the external dimensions of the product, and a front stage die having a die hole desirably larger than the die hole of the rear stage die on the upper part of the rear stage die; A shaving processing method characterized by shaving a punched blank with a desired shaving pattern by setting a shaving punch with an outer shape equal to the size of the gouging hole.