JPS5832536A - Screw forming device for press die - Google Patents

Abstract

PURPOSE:To obtain a titled screw forming device of extremely simple structure which facilitate the manufacture of an upper die edge and a lower one and also reduces the manufacturing cost of the dies, by thread-cutting a workpiece of a plate material with the upper and lower edges having screw threads. CONSTITUTION:A workpiece 4 of a plate material is placed on the lower die edge 3 of a press equipment 1 and the ram of the press is lowered to form a semicircular recessed part 5 and a semicircular projected part 6 respectively. Then when the ram reaches its lower dead point, the workpiece 4 is threadcut into a screw 7. Namely, in regard to the work of the internal circumferential screw 7 of the recessed part 5, the ram of the press is lowered and a screw thread edge 8 projecting in a semicircular shape in the center of the tip of an upper die edge 2 cuts and bends the workpiece 4 into the center recessed edge 9 of the cutting edge 3 to form the recessed part 5. Further, the ram is lowered up to the lower dead point and then the screw 7 is press-worked in the internal circumference.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thread forming device for a press die that forms a thread with a press die.

Conventionally, when performing thread cutting in a press mold,
Using a commercially available tap, the downward motion of the mold is converted into rotational motion for thread cutting. Alternatively, it is common to provide another drive source such as a motor within the mold and perform thread cutting by rotating a tap.

However, these methods require a driving device to drive the tap inside the μ mold, resulting in an expensive mold. In addition, since thread cutting is performed by rotating the tap, it is not possible to increase the cutting speed of the press very much.As a result, punching, bending, etc. in the same mold are sacrificed, which is the most important feature of press processing. The object of the present invention is to provide a thread forming device for a press die that alternately forms threads on a workpiece using upper and lower cutters provided with threads, with the result that a certain cutting speed is reduced.

An embodiment of the present invention will be described below with reference to the drawings. Figure 1 (al is a plan view of screw holes machined in a plate workpiece, Figure 1 (bl is a cutaway side view of main parts of Figure 1, and !J1 Figure fc) is Figure 1 ( Front view of al, Figure 2 ta
+ is a front view of the upper cutter that forms the thread, Figure 112 (b
l is a side view of Fig. 2 fa), Fig. 3 fil is a front view of the lower cutter, Fig. 3 (b) is a side view of the third enclosure), and Fig. 4 is a recessed part in a plate workpiece. FIG. 3 is a vertical cross-sectional view of the gold layer of the main part when forming the screw with the screw thread knife of the upper mold knife. Invention μN84
Figure (two shown press equipment 1 gIp12 figure and !IfII
Attach the upper cutter 2 and the lower cutter 3 shown in Fig. a, and place the workpiece 4 in the semicircle shown in Fig. 1(b) by lowering the ram of the press using the overwriting device of the lower cutter 3. The arc-shaped concave portion 5 and convex portion 6 are each formed into a semicircular arc shape, and when the bottom dead center is reached, a screw 7 is formed on the workpiece. For example, W! The method of machining the inner circumferential screw 7 of the semicircular arc-shaped recess 5 of the workpiece 1 shown in FIG. The threaded knife 8 is
The plate workpiece 4 is cut into the concave cutter 9 at the center of the knife 3 to form a semi-circular concave s5, and when the ram of the press descends and reaches the bottom dead center, the inner A screw 7 is formed around the circumference by press working. Incidentally, at the same time as the screws 7 are machined on the inner periphery of the semi-circular concave portion 5 of the workpiece 40, the method of machining the screws 7 inside the semi-circular convex portion 6 of the work piece 4 is to machine both sides of the tip of the lower cutter 3. A screwed cutter 10 protruding in a semicircular arc shape is attached to the upper cutter 2.
A plate workpiece 4 is cut and bent into the concave blades 12 on both sides of the plate to form a semicircular arc-shaped convex portion 6 above, and when the ram of the press descends and reaches the bottom dead center, the convex One screw hole 7 is formed on the inner circumference of the portion 6 by press working, and a screw hole 13 is formed all at once.

As described above, according to the present invention, in the descending stroke of the press, the upper die cutter and the lower die cutter individually form the threads, so the structure is extremely simple, and the molds for the upper die cutter and the lower die cutter are formed. Since it is easy to manufacture, it has the effect of reducing mold manufacturing costs.

In addition, because the operation is simple, there are fewer failures, and the cutting speed can be made as fast as general press processing, making it possible to obtain screw forming processing suitable for mass production using high-speed press processing. You can obtain a mold screw forming device.

[Brief explanation of the drawing]

Fig. 1 jB) is a plane IA where screw holes are machined in a plate workpiece, Fig. 1 (b) is a cross-sectional view of the main part of Fig. 1 iB), and Fig. 1 10> is a plane view of Fig. 1 jl) front view, vlPI2 figure fal U front view of the upper cutter, W12 figure tbl tU figure 2) a) side view, figure 3 ja) a front view of the lower cutter, figure 3 tb) FIG. 3(a) is a side view, and FIG. 4 is a longitudinal cross-sectional view of a main part of a mold when forming a concave screw in a plate workpiece using a screw thread blade of an upper mold blade. 2... Upper cutter 3... Lower cutler ゛・
4... Plate workpiece 5... Concave portion 6.
...Convex part 7...Screw 8...Central screw thread knife 9...Central concave knife 10...Threaded knife on both sides 12...Concave knife on both sides 13...Screw hole ( 7317) Agent: Patent Attorney Noriyuki Chika (and 1 others)
Figure 1 (0-) (b) (C) Figure 2jl (α) (b) Figure 3 Figure 4

Claims (1)

[Claims] Attach the upper cutter and lower cutter to the press mold device,
In a machine that press-forms a screw by cutting each workpiece of plate material into a semicircular arc shape, the screw thread blade of the upper mold protrudes in the center and has concave blades on both sides, and the screw thread of the opposing lower mold knife protrudes in the center. Center I: A concave knife is provided on each side, and the threaded knife of the upper knife mentioned above is inside the central concave knife of the lower knife, and the threaded knives on both sides of the lower knife are inside the upper knife. In the concave blades on both sides of the plate, each workpiece is cut to form a concave part and a convex part in a semicircular arc shape, and a screw is press-processed at the bottom dead center of the lowering of the ram of the press, and a screw hole is formed. A screw forming device for all press molds, which is characterized by forming.