JPS5929333B2 - How to form a metal plate into a cylindrical shape - Google Patents

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 processed part such as a bent part at one end into a cylindrical shape, such as a film storage cartridge, etc., the above-mentioned 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. As shown in FIG. 1a, this method uses a pair of left and right molding molds 20, 20, which have recesses 21, 21 whose opposing surfaces are approximately semicircular, and which are retractable. The plate s is placed across the metal plate s, and the upper end of the backup material 23, which is cushioned by a spring 22 placed in the center of the molds 20, 20, is brought into contact with the back surface of the metal plate s. The cylindrical core mold 24 located above the center is moved down to sandwich the metal plate s together with the backup material 23, and the core mold 24 is pushed down as shown in FIG. 1b.
When the core die 24 is completely moved down into the mold dies 20, 20, the mold dies 20, 20 are moved down as shown in FIG.
A method is adopted in which the metal plate s is rolled around the peripheral surface of the core mold 24 and formed into a cylindrical shape. However, in the above-described forming method, especially when the core die 24 is moved downward to bend the metal plate s as shown in FIG. Since the process is performed using a long bending fulcrum between the point O due to the clamping with the mold 24 and the point P that abuts the upper edge of the recess 21 of the mold 20, the point O
, P is likely to have a bent portion a as shown in the figure. Therefore, the traces of the bent part a that occurred during the process of forming the metal plate s into a cylindrical shape as shown in Fig. The drawback was 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 in a short and continuous manner around the entire circumference of the metal plate, the metal plate can be shaped into a smooth curved surface. The purpose of the present invention is to provide a molding method that can be processed into a cylindrical 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. In the figure, 1 and 1 are mold dies that face each other closely, and the workpiece plate S The supporting tables 2, 2 have positioning sides 2a, 2a for the workpiece plate. The opposing surfaces of the mold dies 1, 1 are provided with approximately semicircular recesses 3, 3, and these recesses 3, 3 form a perfect circle in the opposing gap (the forward position of the mold dies 1, 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.

A cam pulley 66 is attached to both ends of the drive shaft 5.
A cam groove 7 that is eccentric in the thickness direction of the pulley is provided on the rotating peripheral surface of both cams 6. In both cam grooves 7, 7, cam rolls 10 are attached via shaft pins 9, 9 to flanges 8, 8 protruding from the molds 1, 1, respectively.
, 10 are involved. As a result, the drive shaft 5 receives the driving force of a motor (not shown) and rotates together with the cams 6, 6, thereby moving the cam rolls 10, 10 engaged in the cam grooves 7, 7 of the cams back and forth. The molds 1, 1 can be moved forward and backward.
Further, a back-up material 11 is arranged between the mold dies 1, 1, and its upper end reaches the same plane as the tables 2, 2 of the mold dies 1, 1. The seat 11a of this back-up member 11 is spring-loaded with a spring 12. On the other hand, a cylindrical core mold 13 that can be raised and lowered above the center of the backup material 11 is arranged above the molding molds 1,1.

The means for lifting and lowering the core mold 13 is such that a crank 14 supports its shaft 15 on the machine frame 4, and a rod 1 attached to the crank 14 supports the crank 14 on the machine frame 4.
A lifting rod 17 is connected to 6 with a pin 18, and the lifting rod 17
The core mold 13 is provided at the lower end of the core. 19 is lifting rod 1
This is the guide who shows you around 7.

The forward and backward movement of the mold dies 1, 1 and the vertical movement of the core mold 13 are linked.

That is, when the core die 13 starts to descend, the mold die 1
. When the mold 13 reaches the maximum lowering time, the core mold 13 is moved to the mold mold 1,
completely covered by 1. Note that when the core die 13 rises, the mold dies 1, 1 move backward and forward in the same manner as described above and return to their original positions. FIG. 5 is a diagram of a workpiece S formed into a cylindrical shape by the method of the present invention, and is made of, for example, a rectangular metal plate for use in Batrone 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 S is placed in a mold 1,
When the workpiece plate S is positioned astride the tables 2 and 2 of 1 and then lowered the core mold 13, the core mold 13 moves downward.
and the back-up material 11, and in conjunction with the downward movement of the core die 13, the mold dies 1, 1 begin to retreat to the left and right. This retraction of the mold dies 1, 1 is caused by the upper edges 3a, 3a of the recesses 3, 3 retracting along the circumferential surface of the core mold 13, so that the workpiece plate S is pushed back into the recess as shown in FIG. Upper edge 3
a, 3a and is gradually molded onto the circumferential surface of the core mold 13, and when the core mold 13 is completely covered by the mold molds 1, 1, it is covered with the peripheral surface of the core mold 13. The processed plate Sl)S is cut to form a cylindrical body R as shown in FIG. FIG. 4 explains a situation in which the cylindrical body R 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.
The state in which the molds 1, 1 are moving on the circumferential surface of 3 is shown. In other words, with respect to point 0 where the workpiece S is sandwiched between the back-up material 11 and the core mold 13, the core mold 13
The upper edge 3a of the recess 3 moving along the circumferential surface of is the point Pl, p
2, move continuously like pr... Toe 9 The workpiece plate S is processed with short bending supports such as points Pl, P2, P, etc. with respect to point 0, so the workpiece plate S is bent so that no jig portion occurs. It can be formed into a cylindrical body with a smooth curved surface. As explained above, according to the present invention, the above-mentioned bending fulcrum of the workpiece plate is made short and continuous, thereby creating a smooth curved surface that does not have bending traces like that of conventional bending. 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 process diagram of a workpiece plate being formed. FIG. 4 is an explanatory 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.

Claims (1)

[Claims] 1. A method of forming a workpiece plate consisting of a rectangular metal plate having a bent part or other processed part at one end into a cylindrical shape, in which concave parts that are closely opposed and whose opposing surfaces are approximately semicircular are formed. A workpiece plate is placed across the molds that can move forward and backward, and back pressure is applied to the back surface of the workpiece plate by a spring cushion that retracts between the molds. While the workpiece is in contact with the upper end of the material, a cylindrical core mold provided on the central axis of the backup material is moved downward to sandwich and press the workpiece plate between the backup material and the core mold. By lowering the mold, the upper edge of the recess moves backward and forward in conjunction with the core mold, and the workpiece plate is wound around the outer peripheral surface of the core mold. A method for forming a metal plate into a cylindrical shape, characterized by forming the metal plate into a cylindrical shape.