JPH0123618Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an edge insert used in a press, particularly an edge insert attached to an upper die.

B. Prior art For example, a press machine that performs drawing processing includes an upper mold 1, a lower mold 2, a punch 3, and
With the upper mold 1 and the lower mold 2 holding a thin plate press part (blank) 4 cut to a predetermined size, the blank 4 is lifted by relative movement between the upper mold 1 and the punch 3. It is configured to be squeezed into a mold 1 and formed into a cylindrical or square shape.

When drawing in the press machine, the important thing is not to wrinkle the product 4' and to reduce the frictional resistance between the blank 4 and the upper mold 1 and lower mold 2 to improve the sliding of the blank 4. is necessary. Therefore, conventionally, the pressing surfaces of the upper die 1 and the lower die 2 that press and hold the blank 4 are finished to be flat and mirror-finished.

However, in large press machines, the upper mold 1 and lower mold 2
Because the blank 4 is cast, the frictional resistance is large and slippage is poor, so edge inserts 5 and 6 made of die steel or the like with good slippage are usually attached to the corners of the blank 4 where slippage occurs. As described above, by using the edge inserts 5 and 6 with good sliding properties, the drawability can be improved, but the blank 4
When the amount of sliding increases, the blank 4 slides under strong pressure, which generates a large amount of heat due to friction between the blank 4 and the edge insert 5, which may cause seizing or damage the product 4', or cause the blank 4 to slip under strong pressure. There was a problem in that the amount of deformation of the material increased, causing breakage.

Therefore, conventionally, lubricating oil is interposed between the blank 4 and the edge insert 5 in order to reduce the frictional resistance. Conventionally, it has been difficult to supply this lubricating oil to the edge insert 5, so it has been applied to the surface of the blank 4 in a previous step or dripped using a special machine.

As described above, in the past, lubricating oil had to be applied in the previous process, and moreover, it had to be applied over a wide area, resulting in a large number of man-hours and poor work efficiency. Another problem was that dedicated workers and machines were required, resulting in high costs.

In addition, between the edge insert 5 attached to the upper die and the blank 4, the lubricating oil tends to separate from the edge insert 5 due to gravity, and strong pressure is applied, so the edge insert 5 does not move even in one drawing process. The oil film ran out, and lubricating oil had to be applied after each process, making the work extremely complicated.

On the other hand, when the edge insert 5 becomes large, it is difficult to integrally mold it, so as shown in FIG. 3, a split type edge insert 5 is used, which is a combination of a plurality of edges 5a, 5a, . . . divided into small pieces. In such an edge insert 5, due to distortion during heat treatment, etc., a minute step is formed at each joint portion 5b, 5b, etc., and pressure concentrates on this step, causing oil film breakage.
Burn-in and the like often occurred. The above-mentioned problem becomes a serious problem when the upper surface of the blank 4 becomes the product surface, resulting in a very high rate of defective products.

(b) Purpose of the invention This invention enables continuous supply of lubricating oil and eliminates the need to apply lubricating oil to the blank in the previous process, improving work efficiency and simplifying the work. It is an object of the present invention to provide an edge insert for a press that can reliably prevent oil film from running out.

C. Structure of the invention The edge insert in this invention is constructed by combining a plurality of edges divided into small pieces, and an oil sump through hole is bored in the center of each edge along the longitudinal direction. Lubricating oil is stored in the through-hole, and the end surfaces of each edge are brought into contact with each other with a surface pressure sufficient to allow the lubricating oil to seep out.

In the edge insert with the above structure, the lubricating oil stored in the through hole oozes out to the surface of the edge insert through the small gap between the end faces of each edge due to capillary action, gravity, etc. Always supply lubricating oil.

D. Embodiment FIG. 4 is a drawing showing an embodiment of the present invention, and shows a press that performs a drawing process in which the upper surface of the blank 4 becomes the surface of the product. In the figure, 10 is a lower mold, and edge inserts 11, 11 with good sliding properties are attached to each part that presses the peripheral edge of the blank 4. 12
is an upper die, and edge inserts 13, 13 with good sliding properties are attached to the corners into which the blank 4 slides. 14 is punch. The edge inserts 11, 11 attached to the lower die 10 are the same split type edge inserts as in the prior art.

Edge insert 13 attached to upper mold 12
For example, as shown in FIG. 5, a plurality of edges 15a, 15b to 15e divided into small pieces are arranged so that the end surfaces of each edge 15a, 15b to 15e are such that the lubricating oil 19 described later can seep out. They are assembled into a predetermined shape so that they come into contact with each other under pressure. This edge insert 13 has each edge 1
Oil reservoir through holes 16a to 16e are drilled along the longitudinal direction in the center of each of the through holes 16a to 15e.
a to 16e to the joint part 1 of each edge 15a to 15e.
7a to 17d are communicated. In addition, the through holes 16a, 16e of the edges 15a, 15e at both ends
After storing lubricating oil 19 inside, plugs 18, 18 are filled and sealed.

When the blank 4 is drawn using the upper mold 12 equipped with the edge inserts 13, 13 having the above structure, each edge 15 constituting the edge insert 13
Even if the end faces of a to 15e are finished with high precision, small gaps are created at each joint part 17a to 17d, and the through holes 16a are formed through the gaps due to the action of gravity acting on the lubricating oil 19 itself and capillary action. ~1
The lubricating oil 19 in 6e oozes out and spreads over the surfaces of the edge inserts 13, 13, so during machining, the lubricating oil 19 is interposed between the blank 4 and the edge inserts 13, 13, and even under strong pressure, both 4, 13 The frictional resistance between the edges is small, and even if there is a slight step at each joint 17a to 17d of the edge insert 13, the lubricating oil 19 is continuously supplied to each joint 17a to 17d, so pressure is concentrated. Good drawing processing can be performed without causing an oil film breakage.

E. Effects of the invention With this invention, if lubricant is stored in the through-hole of the edge insert, the lubricant is automatically and continuously supplied to the surface of the edge insert from each joint. There is no need to apply lubricating oil, which reduces the number of man-hours, and also eliminates the need to supply lubricating oil over a long period of time, greatly simplifying the work.

In addition, since lubricating oil is supplied from each joint of the edge insert, a large amount of lubricating oil is present at the joint where pressure is concentrated, and no oil film breaks. Therefore, when drawing a product with the top surface of the blank serving as the product surface using an upper mold equipped with this edge insert, the yield rate of the product is greatly improved without causing burning or scratches.

[Brief explanation of the drawing]

1 and 2 are cross-sectional views showing an example of a conventional press for drawing, FIG. 3 is an enlarged front view showing a conventional press edge insert, and FIG. 4 is a press equipped with an edge insert according to the present invention. FIG. 5 is a cross-sectional view of an example of the press, and FIG. 5 is a cross-sectional view of its edge insert. 4...Pressed parts (blank), 10...Lower mold,
11... (lower mold) edge insert, 12...
Upper mold, 13... (upper mold) edge insert, 1
4...Ponchi, 15a-15e...Etsuji, 16
a to 16e... through holes, 17a to 17d... joints, 19... lubricating oil.

Claims (1)

[Scope of utility model registration request] It is an edge insert constructed by combining a plurality of edges divided into small pieces, and an oil sump through hole is bored in the center of each edge along the longitudinal direction, and lubricating oil is poured into the oil sump through hole. An edge insert for a press, characterized in that it has a reservoir and the end surfaces of each edge are brought into contact with each other with a surface pressure that is sufficient to allow lubricating oil to ooze out.