JPS5942123A - Method of forming metallic plate into cylindrical form - Google Patents

Abstract

PURPOSE:To form a cylindrical body having smooth curved surface by making the bending fulcrum of a plate to be worked short and performing bending continuously. CONSTITUTION:When a plate S to be worked is placed over tables 2, 2 of mold dies 1, 1 and a core die 13 is moved vertically, the plate S is held between the core die 13 and a back-up member 11, and the mold dies 1, 1 start retreat to left and right interlocking with downward movement of the core die 13. When the mold dies 1, 1 retreat, upper rims 3a, 3a of recessed parts 3, 3 retreat along peripheral face of the core die 13, and the plate S is bent by upper rims 3a, 3a of recessed parts, and formed gradually by the peripheral face of the core die 13. When the core die 13 is enclosed perfectly by the mold dies 1, 1, the plate S is enfolded around the core dies 13, and a cylindrical body is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of forming a metal plate into a cylindrical shape.

Generally, a roll forming method is widely used as a method for forming a metal plate into a cylindrical shape. However, when forming a metal plate having a bent portion or other processed portion at one end into a cylindrical shape, such as for example in a film storage cartridge, the roll forming method is extremely difficult. Therefore, in the case of such a metal plate, a forming method as shown in FIG. 1 is used. In this method, as shown in FIG. 1 (&), a bent portion Sa is formed at one end on a pair of left and right molding molds 20, 20 that can move forward and backward, and have semicircular recesses 21 and 21 on opposing surfaces. The spring 22 is placed across the metal plate S having the metal plate S, and is placed in the middle of the mold 20.
The upper end of the back-up material 23, which is spring-cushioned, is brought into contact with the back surface of the metal plate S, and thus the back-up material 2
The cylindrical core mold 24 located above the center of the plate 3 is moved downward to sandwich the metal plate S together with the back-up material 23.
), when the molds 20, 20 are completely moved down into the inside of the molds 20, 20, move the molds 20, 20 forward as shown in FIG. The method used is to form it into a cylindrical shape. However, in the above-mentioned forming method, when the core die 24 is moved down to process the metal plate S as shown in FIG. Point 0. is processed using a long bending fulcrum between point O due to the clamping with the core die 24 and point P that abuts the upper edge of the recess 21 of the mold die 20. A bent portion a as shown in the figure is likely to occur in the metal plate portion between P.

Therefore, the traces of the bends QH7jS a that occurred during the process of forming the metal plate S into a circular ihJ shape as shown in Fig. 1(c) will remain, and the final product will have a polygonal shape as a whole. Therefore, it had the disadvantage that it was difficult to create a cylindrical body with a smooth curved surface.

This invention aims to solve the above-mentioned drawbacks of the conventional art, and by moving the bending fulcrum over the entire circumference of the metal plate in a short and continuous manner, the metal plate can be shaped into a cylinder with a smooth curved surface. The purpose is to provide a molding method that can be processed into a body.

An embodiment of the present invention will be described below based on the drawings. Fig. 2 shows an apparatus for carrying out the method of the present invention. The supporting tables 2, 2 have positioning sides 2a, 2a for the workpiece plate. The opposing surfaces of the mold dies 1 and 10 are provided with semicircular recesses 3 and 3, and these recesses 3 and 3 form a perfect circle in the opposing gap (the forward position of the mold dies 1 and 1) as shown in the figure. It is showing.

Both molds 1, 1 can slide on rails 4a of a machine frame 4, and a drive shaft 5 is supported on the machine frame 4. Cam pulleys 6.degree. 6 are pivotally attached to both ends of the drive shaft 50, and cam grooves 7 are provided at rotational angles of both cam pulleys 60, which are eccentric in the thickness direction of the pulleys.

Cam rolls 10.10 are fitted into both cam grooves 7, 7, respectively, and are attached to flanges 8, 8, which are raised from the molding die 1.degree. 1, via shaft pins 9.9. As a result, the drive shaft 5 rotates together with the cam pulleys 6, 6 under the driving force of a motor (not shown), thereby moving the cam rolls 10, 10 engaged in the cam grooves 7, 7 of the cam pulleys forward and backward. The molds 1, 1 can be moved forward and backward. Further, a back-up material 11 is arranged between the molds 1.1, and its upper end reaches on the same plane as the tables 2, 2 of the molds 1, 1. This back-up material 11 has a seat 11a cushioned by a spring 12.

On the other hand, a cylindrical core mold 13 that can be raised and lowered above the center of the back-up material 11 is arranged above the molding molds 1, 1. The lifting means for the core mold 13 is such that a crank 14 supports a shaft 15 on the machine frame 4, a lifting rod 17 is connected to a rod 16 attached to the crank 14 by a pin 18, and the lower end of the lifting rod 17 is connected to a rod 16 attached to the crank 14. The core mold 13 is provided. 19
is a guide guiding the elevator rod 17.

The forward and backward movement of the mold dies 1, 1 and the up and down movement of the core mold 13 are linked. That is, when the core die 13 begins to descend, the mold dies 1, 1 begin to retreat, and the long diameter portion d of the core die 13 reaches the glue portions 2, 2 of the mold die 1.1.
When passing through the upper edges 2a, 2a of the molds 1, 1,
moves forward, and when the core metal W13 reaches the maximum downward position, the core metal die 13 is completely enclosed by the mold dies 1, 1.

Incidentally, when the core die 13 is raised, the mold die 1.1 moves backward and forward to its original position in the same manner as described above.

FIG. 5 is a diagram of a workpiece S formed into a cylindrical shape by the method of the present invention, which is made of, for example, a rectangular metal plate for use in a cartridge, etc., having a bent portion Sa at one end.

Next, a method for forming the workpiece plate S into a cylindrical shape will be explained. First, as shown in Fig. 2, the workpiece plate S is positioned astride the tables 2, 2 of the mold dies 1, 1, and then when the core mold 13 is lowered, the workpiece plate S moves downward. The core mold 13 and the muck-up material 11 are sandwiched together, and the mold molds 1, 1 are interlocked with the downward movement of the u-mold 13.
begins to retreat to the left and right. This retreat of the mold dies 1, 1 is caused by the upper edges 3a, 3a of the recesses 3, 3 retreating along the circumferential surface of the core die 13, as shown in FIG.
is curved at the upper edges 3a, 3a of the concave portion and gradually molded onto the circumferential surface of the core mold 13, and when the core mold 13 is completely enclosed by the mold dies 1, 1, the core metal A workpiece plate S is wound around the circumferential surface of the mold 13, and a cylindrical body R as shown in FIG. 6 is formed.

FIG. 4 explains a situation in which the cylindrical body 1N formed as described above can be processed into a smooth curved surface.

In the figure, core mold 1 is shown to make it easier to understand the molding state.
It is shown in a state 71 that the molds 1, 1 are moving on the circumferential surface of the mold 3. That is, with respect to point 0 where the workpiece plate S is sandwiched between the pack amplifier material 11 and the core mold 13, the upper m3a of the recess 3 moving along the circumferential surface of the core mold 130 is a point P.
# moves continuously like , , P, , P,... In other words, the workpiece plate S is at point P relative to point O, , 1)
2. By being processed using a short bending fulcrum as shown in P3..., the workpiece plate S can be formed into a cylindrical body with a so-called smooth curved surface without any bends.

As explained above, according to the present invention, the above-mentioned bending fulcrum of the workpiece plate is made short and continuous, and a smooth curved surface without bending traces as in the conventional method is achieved. It is possible to mold a cylindrical body of 1,000 yen, thereby making it possible to obtain a cylindrical product with high product value.

[Brief explanation of drawings]

Fig. 1 is a process diagram for explaining the conventional cylindrical forming method, Fig. 2 is an overall configuration diagram of an apparatus for carrying out the method of the present invention, and Fig. 3 is a forming of a workpiece and processed plate. The process diagram in the middle, FIG. 4 is an enlarged view showing how the plate to be processed is formed into a cylindrical shape, FIG. 5 is a perspective view of the plate to be processed, and FIG. 6 is a perspective view after forming. DESCRIPTION OF SYMBOLS 1... Mold die, 3... Recessed part, 3a... Upper edge of recessed part, 11... Bank up material, 12... Spring, 1
3... Core die, S... Work plate. Figure 1 (C) Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 n

Claims (1)

[Claims] A method of forming a workpiece plate made of a rectangular metal plate having a bent part or other processed part at one end into a cylindrical shape, in which the workpiece plate is formed into a cylindrical shape, and the opposing faces have four semicircular parts that are closely opposed to each other. A workpiece plate is placed across the mutually movable molds, and back pressure is applied to the back surface of the workpiece plate by a spring cushion that protrudes and retracts between the molds. While in contact with the upper end of the back-up material, a cylindrical core mold provided on the central axis of the back-up material is moved downward to sandwich the workpiece plate between the back-up material and the core mold. By pressing down on the core mold, the upper edges of the four parts of the mold move backward and forward along the circumferential surface of the core mold, and the workpiece plate is moved into the core mold. A method for forming a metal plate into a cylindrical shape, characterized by forming the metal plate into a cylindrical shape by rolling it around the outer peripheral surface.