JPH06344049A - Shearing method by press - Google Patents

Abstract

PURPOSE:To manufacture tooth form parts, etc., of which whole surface is a sheared section without roll over. CONSTITUTION:A first working process is such that a sheet metal 100 that is set in a first die is worked for a half blanking for a first target shearing contour CONT 1 by a first punch having a negative first clearance, a return working force is applied on the metal from the bottom, and a first semi-finished article 200 and scrap are separated. A second working process is such that the first semi-finished article 200 which is turned upside down and set in a second die is pressed by a second punch having a negative second clearance, and, while a roll over due to the first working process is crushed, a shaving is performed for a second target shearing contour CONT 2 to obtain a second semi-finished article 300. A third working process is carried out, successively in this order, such that the second semi-finished article 300 on a third die is pressed by a third punch 11C having a positive third clearance and that a shaving is performed for the final shearing contour CONT 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shearing method for manufacturing tooth profile parts and the like using a press machine.

[0002]

2. Description of the Related Art FIG. 6 shows a case where a press machine 10 punches and shears, for example, a circular blank 110. In the same (A), when the plate material 100 is sheared at once by the punch 11 having a positive clearance with respect to the die 12, that is, the punch 11 having an outer diameter smaller than the inner diameter of the die 12, the blank 110 shown in the same (B) is obtained. A new surface composed of a fracture surface B and a shear surface S appears on the outer peripheral surface (cut surface).

By the way, among various industrial parts, many must have a sheared surface S on the entire surface and a drafted sagging surface is not allowed. In particular, a small and thin tooth profile component is strongly required to have a sheared surface S on the entire surface without sagging on the upper and lower surfaces. Thus, both of these requirements cannot be satisfied by press punching the blank 110 at once. Further, if the fracture surface B is large, it is not suitable as a tooth profile part.

If press working is performed by a so-called fine blanking method here, the generation of the fracture surface B can be prevented, but the generation of the sagging surface cannot be prevented. On the other hand, various methods for processing parts such as spur gears while reducing the occurrence of sagging surfaces have been proposed. For example, JP-A-63-25
No. 31, 2532, 10037, 13640 and Japanese Patent Laid-Open No. 64-2736.

[0005]

However, in any of the above-mentioned conventional processing methods, it is not possible to form a good punched surface which has advantages and disadvantages and has a sheared surface on the entire surface and does not have a sagging surface at the top and bottom. In particular, when manufacturing ratchet internal teeth, involute internal teeth, and tooth profile parts that partially have involute external teeth, the sag of the tooth profile convex portion that is the shear profile becomes extremely large. The contact area at is insufficient. Thus, the fact is that the material (plate material) is conventionally thickened to prevent the sagging.

However, this conventional measure cannot be said to be drastic. This is because the increase in the thickness of the finished product becomes a fatal defect in today's demand for thinner tooth profile parts. In other words, it is difficult to allow the cutting to be performed after the press processing, because the cost will increase.

It is an object of the present invention to provide a shearing method using a press machine capable of producing a tooth-shaped part or the like having a sheared surface on the entire surface and no sagging surfaces on the upper and lower sides.

[0008]

A shearing method using a press machine according to the present invention is a method of shearing a plate material to a first die in a state in which a component side of a first target shearing profile is pressed against the upper surface of a first die using a stripper. After setting, subsequently, using a first punch having a negative first clearance with respect to the first die, a pressing force is applied from the upper first surface side of the plate material to perform half blanking with the first target shearing contour, and thereafter, A first process for forming a first semi-finished product by using a reverse plate retainer slidable in the first die and applying a returning process force from the lower second surface side to separate the component side and the scrap side. The first step in the state where the first surface and the second surface of the first semi-finished product are reversed and the component side of the second target shearing profile is pressed against the upper surface of the second die using a stripper Set the semi-finished product on the second die, and then the absolute value is the first clearance. Is smaller than the second die and has a negative second clearance with respect to the second die, and a pressing force is applied from the second surface side above the first semi-finished product to the sag surface generated in the first processing step. The second processing step of forming the second semi-finished product by shaving with the second target shearing profile while eliminating the second die, and the third die using the stripper on the component side of the final shearing profile of the second semi-finished product. The second semi-finished product is set on the third die while being pressed against the upper surface of the
Finished by shaving with the final shearing contour by applying a pressing force from the upper second surface side of the second semi-finished product using a third punch that is smaller than the clearance and has a positive third clearance with respect to the third die. A third processing step for forming the product,
And has a feature that the shaving allowance is reduced in the subsequent process in this order.

[0009]

In the case of the present invention having the above construction, the first punch having the first negative clearance is used as shown in FIG.
Pressing force is applied from the upper first surface side of the plate set on the die to perform half blanking with the first target shear profile, and then reverse plate pressing is used to apply a returning processing force from the lower second surface side to the component side. A first semi-finished product is formed in the first processing step of separating the scrap side from the scrap side. Since the half punching process uses the first punch and the first die having a negative clearance and the reverse plate retainer, the occurrence of secondary fracture can be significantly suppressed.

Next, the upper and lower surfaces of the first semi-finished product are inverted (FIG. 4) and set on the second die, and the pressing force is applied from the upper second surface side using the second punch having the negative second clearance. The second semi-finished product is formed in the second processing step of shaving the second target shearing contour while adding. On this occasion,
The shaving surface caused by the first processing step disappears because the plate material is compressed on the upper surface of the second die by the shaving process. Further, since the shaving cost in the second processing step is small, no new sag surface is generated.

Subsequently, the second semi-finished product is set on the third die in the same posture (FIG. 5), and the third punch having the normal positive third clearance is used from the upper surface side thereof and the shaving is much smaller. Shaving is performed in the final shear profile in the machining allowance. That is, by performing the third processing step, it is possible to manufacture a finished product in which the entire surface is a sheared surface and the upper and lower surfaces are not sagging.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. The shearing method by this press machine is shown in FIGS.
It is supposed that the ratchet internal tooth component (100) shown in FIG. 1 is manufactured by the first machining step, the second machining step and the third machining step shown in sequence.

In FIG. 1, four positioning pilot holes 109 are provided in the plate member 100, which is hatched for convenience of description, and each die 12A, 12 described later in detail.
It is used to fit the respective pilot pins (not shown) provided at predetermined positions of B and 12C and to set them accurately on each die. The plate material 100 is JIS G31.
In No. 31, the plate thickness is 4.5 mm. Reference numeral 106 in FIG. 1 denotes a space after punching.

First, the mutual relationship between the processing steps will be described with reference to FIG. CONT1 is the first target shear profile, CON
T2 is the second target shear profile and CONT3 is the final target shear profile. The shaving allowance in each working step is such that the entire circumference of the ratchet internal tooth component is not uniform and the shaving allowance of each convex portion is made smaller toward the subsequent step.

That is, the shaving allowance Za1 between the first target shearing contour CONT1 and the second target shearing contour CONT2 in each convex portion, and the second target shearing contour CONT.
The relationship between the shaving work allowance Zb1 between 2 and the final shearing contour CONT3 is Za1> Zb1. However, the shaving allowance excluding the convex portions is Za2 (> Za).
1) and Zb2 (> Zb1).

Therefore, Za1> Zb1, Za2> Z
Since it is b2, the bending radii RA, RB, RC of each convex portion
Can be RA>RB> RC. That is, the first target shearing contour CONT of the convex portion in the first processing step.
Since the bending radius RA of 1 can be set to be large, it is possible to minimize the secondary fracture that occurs in the cut surface and reduce the sag surface of the convex portion.

A press machine suitable for carrying out the present invention will be described here. FIG. 3 shows the first processing step, in which the die 1 from the first punch 11A and the first die 12A.
0A is formed. 16A is a stripper, and the left side (first semi-finished product 200) side in FIG. 3 with the first target shearing contour CONT1 shown in FIG.
It is pressed against the upper surface of the die 12A with a pressing force P1.
Further, the reverse plate retainer 15A is slidable in the first die 12A, and a pressing force P2 as a returning process is added.

The first punch 11A has a negative first clearance C1 with respect to the first die 12A. That is, the outer diameter of the first punch 11A is larger than the inner diameter of the first die 12A by the first diameter.
Only the clearance C1 is large. This is because it is possible to perform a half blanking process that can suppress the occurrence of secondary fracture on the cut surface. That is, at the bottom dead center of the slide (not shown) to which the first punch 11A is attached, the lower end surface of the first punch 11A is seen from the upper surface of the first die 12A in FIG.
The die height is set so as to be located above the gap L1 shown in 2). Therefore, when the blanking process is performed, the left part (first semi-finished product 200) side and the right scrap (105) side have an uncut portion 101 of thickness L1.
It is in a continuous state with.

Then, as the slide (first punch 11A) rises from the bottom dead center, the reverse pushing plate 15A to which the pushing force P2 is applied rises to separate the uncut portion 101 [the same (A3)]. reference〕. Therefore, the return processing force (P2) is larger than the cutting force P1 and the pressing force P1 is equal to the uncut portion 101.
Is larger than the cutting force P'of. That is,
The relationship is P2 ≧ P1> P ′. However, the pressing force P'is determined by the gap L1. For example, the punching force is 1
3% or more. Incidentally, reference numeral 201 in the drawing denotes a sagging surface generated during the half blanking process.

Further, the first clearance C1 is determined to an appropriate value in consideration of the material and the plate thickness and in relation to the second working process. First punch 11A and stripper 16
A small clearance is provided between A and A in a range that does not hinder sliding. The same is true between the first die 12A and the reverse plate retainer 15A.

FIG. 4 shows a mold 1 for carrying out the second processing step.
Indicates 0B. The die 10B is formed of a second punch 11B and a second die 12B. Reference numeral 15B is a counter, and 16B is a second semi-finished product 200 shown in FIG.
The left side component (second semi-finished product 300) side in FIG. 4 with the target shearing contour CONT2 as a boundary is pressed against the upper surface of the second die 12B with a pressing force P1. Here, the first semi-finished product 200 is set on the second die 12B with its upper and lower surfaces inverted. The sag surface 201 is located below.

The second punch 11B has a negative second clearance C2 with respect to the second die 12A. That is, the outer diameter of the second punch 11B is greater than the inner diameter of the second die 12B by a second value.
Only the clearance C2 is large. This second clearance C
2 is smaller in absolute value than the first clearance C1 due to the relationship of shaving allowance Zb1 <Za1 shown in FIG. The second clearance C2 should be determined by changing the material and the plate thickness, but if it is too small, the sagging surface 201 due to the first processing step cannot be eliminated. However, if it is too large, the shaving residue 205 shown in FIG. 4 (B2) cannot be crushed.
You should choose carefully.

Further, in FIG. 4B1, Δl of the first semi-finished product 200 increases in proportion to the size of the first clearance C1. Therefore, if the first clearance C1 for carrying out the first working step is made too large, the shaving process in the second working step will be hindered.

Thus, if the values of the first clearance C1 and the second clearance C2 are selected and determined to be appropriate values, and the second punch 11B is lowered to apply the pressing force, the second target of the first semi-finished product 200 is obtained. Smooth shaving can be performed with the shearing contour CONT2, and the sag surface 201 generated in the first processing step can be eliminated by being compressed onto the upper surface of the second die 12B.

In FIG. 4B2, a shaving residue 205 generated by the shaving process of FIG. 4B1.
Is not separated from the second semi-finished product 300 because the second punch 11B and the second die 12B do not mesh with each other. That is, at the bottom dead center of the slide, a thickness of L2 remains between the lower surface of the second punch 11B and the upper surface of the second die 12B.
Since the smaller the gap L2 and the gap L1 in the first working process, the better, and therefore, the gap L2 is determined to be the minimum within the range allowed for the bottom dead center accuracy of the press machine.

The upper surface of the second die 12B and the counter 1
The step h1 between the upper surface of 5B and the upper surface of 5B is adjusted by observing the disappearance state of the sag surface 201 generated in the first processing step. If the disappearance is insufficient, it approaches zero (0). On the contrary, if the crushing force is too large, increase it.

In this way, when the second punch 11B is lowered, the first semi-finished product 200 whose upper and lower surfaces are inverted is shaving processed with the second target shearing contour CONT2, and the sagging surface 201 formed by the first processing step. Is the second die 12
It is compressed on the upper surface of B and disappears, and as a result, the second semi-finished product 300 is obtained. At this time, since the shaving allowance Za1 is small, a new sagging surface does not occur due to this working step. Further, the shavings 205 are crushed together with the counter 15B. However, it is not separated from the second semi-finished product 300.

Next, FIG. 5 shows the third working step, in which the die 10C is a third punch 11C and a third die 12C.
It is formed from and. Third punch 11C and third die 1
An ordinary positive clearance C3 whose absolute value is smaller than that of the second clearance C2 is provided between the 2C and 2C. 16C is a stripper.

That is, a pressing force is applied to the third punch 11C to lower it, and shaving is performed on the final target shearing contour CONT3 of the second semi-finished product 300. Although the bending radius RC of the convex portion is small as the final product, the shaving allowance Zb1 is very small, so that a new sag surface does not occur and a good punched surface can be obtained.

Further, since the shaving dregs 207 produced by this shaving process are stacked on the shaving dregs 205 generated in the second machining step, the inner diameter is the second.
It is tightly fitted into the third die 12C, which is larger than the inner diameter of the die 12B, and the scrap is integrated in two steps and has a large volume, so that scrap does not rise. Therefore, it is convenient in terms of shaving processing and scrap processing. This is more effective when the shaving process is performed many times.

Next, this press machine (upper molds 10A, 10
The main shearing method using B, 10C) will be described.

First, the plate member 100 is firstly shown in FIG.
Set on the die 12A. That is, the positioning pilot holes 109 of the plate material 100 are fitted to the pilot pins attached to the first die 12A. And the plate material 10
0 is set in a state where the left side component (first semi-finished product 200) in FIG. 3 (A1) with the first target shearing contour CONT1 shown in FIG. 2 as a boundary is pressed by the stripper 16A to which the pressing force P1 is applied. To do.

As soon as the setting of the plate material 100 is completed, the press drive is performed to lower the first punch 11A having the negative first clearance C1 so that the plate material 100 is bitten. Furthermore, as shown in the same (A2), it is lowered to the bottom dead center. A gap L1 is provided between the first punch 11A and the first die 12A at the bottom dead center. Therefore, the plate material 100 is half blanked. Since the machining allowance is large, the sagging surface 201 is generated on the left side of the plate material 100. However, since the gap L1 is provided, it is possible to significantly suppress the occurrence of secondary fracture on the cut surface, and it is possible to make the entire surface into a sheared surface. At this time, the component (200) side and the scrap (105) side are connected at the uncut portion 101.

Next, when the first punch 11A rises toward the top dead center, the reverse pressing plate 15A to which the pressing force (returning processing force) P2 is applied rises as shown in (A3). Since this pressing force P2 is larger than the cutting force P'of the uncut portion 101, the component (200) side and the scrap 105 side can be separated. Thus, the second processing step makes it possible to form the first semi-finished product 200 having no fracture surface.

Next, the first semi-finished product 200 is turned upside down and the positioning pilot holes 109 are used in the same manner as in the above case, and the second die 12B shown in FIG. 4B1 is obtained.
Set to. The left side of the second target shearing contour CONT2 is pressed by the stripper 16B and set.

A second punch 11B having an absolute value smaller than the first clearance C1 and having a negative second clearance C2.
When is lowered, shaving can be performed with a small shaving allowance Za1. Since the bending radius RB of the convex portion is large, a new sag surface does not occur. Moreover, the sagging surface 201 generated by the first processing step is the second die 1
It is compressed on the upper surface of 2B and disappears.

Also, at the bottom dead center, the second punch 11B
Does not mesh with the second die 12B. That is, FIG. 4 (B2)
Since the gap L2 is provided, the shaving residue 205 generated by the shaving process is not separated from the second semi-finished product 300 and is crushed by the cooperation of the second punch 11B and the counter 15B.

Therefore, by this second processing step,
While eliminating the sag surface 201 generated in the first processing step, without causing a new sag surface under the condition that the bending radius RB of the convex portion is relatively large and the shaving process allowance Za1 is small, Good shaving can be done. That is, the second semi-finished product 300 can be obtained.

Subsequently, the second semi-finished product 300 is held in the same posture, and the second die 12C shown in FIG.
Set the semi-finished product 300. Final shear contour CONT3
The left side (finished product 400) side with the boundary as a boundary is pressed onto the third die 12C by the stripper 16C to which a pressing force P1 is applied.

The bending radius RC of the final shearing contour CONT3 in the convex portion of the second semi-finished product 300 is much smaller than the bending radius RB in the second working step (FIG. 5), as shown in FIG. However, the shaving cost Z of the convex portion
Since b1 is made much smaller than the shaving allowance Za1 in the case of the second working step, a new sag surface does not occur and an excellent cut surface can be formed by this third working step.

That is, the third die 12C has a third positive clearance C3 for normal shaving.
While lowering the punch 11C, shaving is performed with the final shearing contour CONT3 shown in FIG. 5 (C1). The shaving residue 207 generated at this time is, as shown in (C2), the shaving residue 2 generated in the second processing step.
05, and both scraps 205 and 207 are firmly fitted into the third die 12C as a unit. Therefore, it is possible to perform a smooth shaving process that does not cause scraps to be generated, and to easily treat scraps.

In this way, it is possible to manufacture a finished product (ratchet internal tooth component) 400 in which the upper surface and the lower surface have no sag surface and the cut surface has a shear plane as a whole.

According to this embodiment, however, the first punch 11A having the negative first clearance C1 is used for the first die 12A to apply the pressing force from the upper first surface side of the plate material 100. 1 Half-cutting is performed with the target shearing contour CONT1, and then the reverse plate pressing member 15A is used to apply a returning processing force P2 from the lower second surface side (first semi-finished product 200).
The first semi-finished product 200 by separating the side and the scrap 105
And the first semi-finished product 200 are set upside down and set on the second die 12B, and the absolute value is smaller than the first clearance C1 and the second die 12
While using the second punch 11B having a negative second clearance C2 with respect to B, a pressing force is applied from the upper second surface side thereof to eliminate the sag surface 201 generated in the first processing step,
A second processing step of forming the second semi-finished product 300 by shaving with the second target shearing contour CONT2, and the third die 12 while keeping the posture of the second semi-finished product 300 as it is.
C, and the pressing force is applied from the upper second surface side using the third punch 11C having an absolute value smaller than the second clearance C2 and having a normal positive third clearance C3 with respect to the third die 12C. And a third processing step of forming the finished product 400 by shaving with the final shearing contour CONT3, and in this order, the shaving processing allowances Za1, Zb1, Za2, Zb2 become smaller as going to the post-processing step. Since this is a method of performing shearing by performing each processing step, it is possible to manufacture a good product even if it is a tooth-shaped component having a convex portion without a sagging surface and having a cut surface entirely on a sheared surface.

Further, the shaving allowances are not uniform all around, and the shaving allowances Za1, Zb1 of the convex portions are made smaller than the other shaving allowances Za2, Zb2 and become smaller in the subsequent process steps, and Since the bending radii RA, RB of the convex portion in the previous processing step are increased, the secondary fracture can be suppressed to a minimum and the sagging surface 201 can be significantly suppressed even if the thickness of the plate material 100 is reduced.

In the first working step (FIG. 3), the uncut portion 101 having the dimension L1 is left and the reverse plate holder 15 is left behind.
Since the first semi-finished product 200 and the scrap 105 are formed so as to be separated from each other by using A, a good drafted surface can be formed.

In the second processing step (FIG. 4), since the upper and lower surfaces of the first semi-finished product 200 are inverted and shaving processing is performed, the sag surface 201 generated by the first processing step is formed on the second die 12B. It can be completely eliminated by compressing it, and since the shaving process allowance Za1 is small, it is not necessary to generate a new sag surface.

In the second processing step (FIG. 4), since the gap L2 is provided between the second punch 11B and the second die 12B at the bottom dead center, the shaving residue 205 does not separate and the counter Since it is crushed by 15B,
Can be processed smoothly.

Further, in the third working step (FIG. 5), the bending radius RC of the convex portion is made small, but the shaving work allowance Zb2 is made smaller, so that even if normal shaving work is carried out. The sagging surface does not occur.

Further, the shaving dregs 207 generated in the third working step (FIG. 5) is stacked with the shaving dregs 205 generated in the second working step (FIG. 4) and
Since it is fitted in the die 12C, a smooth shaving process can be performed without generating scraps and scrap processing is easy.

Further, since the plate member 100 is provided with the four positioning pilot holes 109, it is possible to accurately position it on the respective dies 12A, 12B and 12C for carrying out the respective processing steps. Therefore, the highly accurate finished product 400 can be manufactured. Together with the plate material 100, the first semi-finished product 200, the second
The semi-finished product 300 can be automatically conveyed to the next mold 10B, 10C or the like.

[0051]

According to the present invention, the first punch having a negative first clearance with respect to the first die is used to apply a pressing force from the upper first surface side of the plate material so that the first target shearing contour is obtained. Punching is performed, and thereafter, using a reverse plate retainer, a returning process force is applied from the lower second surface side to separate the component (first semi-finished product) side and the scrap to form a first semi-finished product. And the second punch with the first semi-finished product turned upside down and set on the second die, and the absolute value is smaller than the first clearance and the second punch has a negative second clearance with respect to the second die. By applying a pressing force from the upper second surface side using
The second processing step of forming the second semi-finished product by shaving with the second target shearing contour while eliminating the sag surface generated in the processing step of Set the die and use a third punch with an absolute value smaller than the second clearance and having a normal positive third clearance with respect to the third die, and apply a pressing force from the upper second surface side to make the final shear profile. And a third processing step of forming a finished product by shaving, and in this order, each processing step is performed while the shaving processing cost is reduced toward the post-processing step, and shearing processing is performed. Therefore, even a tooth-shaped component having a convex portion or the like can be manufactured as a good product in which there is no sagging surface and the cut surface is entirely sheared.

[Brief description of drawings]

FIG. 1 is a diagram for explaining a plate material according to an embodiment of the present invention.

FIG. 2 is also a diagram for explaining a shaving allowance in each processing step.

FIG. 3 is also a diagram for explaining the first processing step.

FIG. 4 is likewise a diagram for explaining a second processing step.

FIG. 5 is also a diagram for explaining the third processing step.

FIG. 6 is likewise a view for explaining a cut surface according to a conventional example.

[Explanation of symbols]

10A 1st die 10B 2nd die 10C 3rd die 11A 1st punch 11B 2nd punch 11C 3rd punch 12A 1st die 12B 2nd die 12C 3rd die 15A Reverse plate retainer 15B Counter 16A, 16B, 16C Stripper 100 Plate material 101 Uncut part 105 Scrap 109 Positioning pilot hole 200 First semi-finished product 201 Dull surface generated by the first processing step 205 Shaving debris generated by the second processing step 207 Generated by the third processing step Shaving scrap 300 Second semi-finished product 400 Completed product CONT1 First target shearing profile CONT2 Second target shearing profile CONT3 Final shearing profile Za1, Za2 Shaving allowance by the second working process Zb1, Zb2 Shaving by the third working process Processing cost R , RB, the RC protrusion bending radius

Claims (1)

[Claims] 1. The first plate member is placed in a state where the component side of the first target shear profile is pressed against the upper surface of the first die using a stripper.
The die is set, and then the first punch having a negative first clearance with respect to the first die is used to apply a pressing force from the upper first surface side of the plate material to perform half blanking with the first target shearing contour, Then, a reverse plate retainer slidable in the first die is used to apply a restoring force from the lower second surface side to separate the component side and the scrap side to form a first semi-finished product. In the state where the first surface and the second surface of the first semi-finished product are reversed and the component side of the second target shearing profile is pressed against the upper surface of the second die using a stripper. First half finished product second
Set on the die and then press from the second surface side above the first semi-finished product using a second punch having an absolute value smaller than the first clearance and a negative second clearance with respect to the second die. A second processing step of forming a second semi-finished product by applying a force to eliminate the sagging surface generated in the first processing step and shaving with the second target shearing contour; and The second semi-finished product is set on the third die with the part side of the final shearing profile pressed against the upper surface of the third die using a stripper, and then the absolute value is smaller than the second clearance and on the third die. On the other hand, a third working step of forming a finished product by applying a pressing force from the upper second surface side of the second semi-finished product by using a third punch having a positive third clearance to perform shaving with the final shearing contour. ,, and and in this order Shearing method according to a press machine which is characterized in that smaller toward the post-processing step Bing machining margin.