JPS62127129A - Working method for bulge - Google Patents

Abstract

PURPOSE:To improve workability etc., by equipping hollow part for storing a cylindrical body inside a die and installing plural grooves, then forming bulges successively on the cylindrical body through a pair of pistons set oppositely. CONSTITUTION:The hollow parts 9 for storing the pipe 4 respectively on the upper die 2 and the lower die 3 composing the dies 1 and the plural grooves 10 are installed at a prescribed distance in the longitudinal direction. At first, the first and second pistons 5, 8 are inserted from the right and left openings into the pipe 4 inserted in the hollows 9 to fix the pistons 5, 8 at the positions corresponding to the arbitrary grooves 10. A pressurizing fluid 6 is fed forcibly to a passage 7 of the piston 5 and the fluid 6 is injected into the pipe 4 to form the bulge parts 17 in the pipe 4. The pistons 5, 8 are moved successively to form the bulge parts 17 in order at the place corresponding to the other groove 10. In this way, the workability is improved and the number of dies are reduced.

Description

[Detailed description of the invention] a. Industrial application field The present invention relates to a bulge processing method.

b. Prior Art Conventionally, automotive camshafts and the like have been molded, for example, by a bulge process (fluid press) using a mold 50 as shown in FIGS. 2 and 3. This mold 5
0 consists of an upper mold 54 and a lower mold 55, each of which is provided with a storage recess 52 for storing a pipe 51 that is the raw material for the camshaft, and has a groove 53 formed at opposing positions.

Now, in order to mold a camshaft having a plurality of cams by the bulging method, first the pipe 51 is stored in the storage recess 52 of the mold 50. Next, when a pressurizing fluid is pressurized into the vibrator 51 by an appropriate means, the pipe 51 at a portion corresponding to the groove 53 bulges and deforms toward the groove 53, and a bulge that becomes a cam is formed on the outer peripheral surface of the pipe 51. A section 56 is formed (see FIG. 2). Next, the pipe 51 is inserted into the mold 50.
After removing the pipe 51 from the mold, the pipe 51 is placed in another mold 57 in which two grooves 53 are formed, and bulges 56 are successively formed on the outer peripheral surface of the pipe 51 by the same operation as described above. (See Figure 3).

C1 Problems to be Solved by the Invention However, in the conventional bulge processing method as described above, when a part of the vibrator 51 bulges into the groove 53 of the mold 50, 57, the vibrator 2 simultaneously Since it contracts in the longitudinal direction, it has been difficult to form multiple cams in one process with a normal vibrator due to restrictions on elongation. Therefore, in order to mold a camshaft having a plurality of cams using the conventional bulge processing method, the number of processing steps and molds corresponding to the number of cams are required, and the manufacturing cost of the camshaft is high. Also, when processing a part of a long vibrator to bulge out, a mold with the same length as the vibrator is required.
This led to an increase in the size of the mold.

The present invention has been made in view of the above circumstances, and its purpose is to provide a bulge processing method that can solve the above-mentioned problems.

d. Means for solving the problems In order to solve the problems of the above-mentioned prior art, in the present invention, a storage recess for storing the cylindrical body is provided,
and a splittable mold in which a plurality of grooves are formed in the longitudinal direction at predetermined intervals in the housing recess, a first piston having a passage for pressurizing fluid, and a first piston and the first piston at a predetermined interval. inserting and arranging the cylindrical body into the mold using a second piston facing each other, and slidingly fitting the first piston and the second piston into the self-registering cylindrical body, respectively; Both pistons are moved and fixed in positions corresponding to arbitrary grooves, and in this state, pressurizing fluid is pressurized into the cylindrical body through the passage of the first piston, thereby closing the cylindrical body. The cylindrical body is bulged and deformed toward the groove, thereby sequentially forming a bulge on the outer peripheral surface of the cylindrical body.

Hereinafter, the present invention will be explained in detail based on illustrated embodiments.

FIG. 1 explains one embodiment of the present invention. In the figure, l is a mold consisting of an upper mold 2 and a lower mold 3, 4 is a vibrator that is the raw material for the camshaft, and 5 is a pressurizing fluid 6. A first piston 8 having a passage 7 is a second piston disposed facing the first piston 5 at a predetermined distance. Above upper mold 2
Each of the lower molds 3 is provided with a storage recess 9 for storing the vibrator 4, and a plurality of grooves 1O are formed in the storage recess 9 at predetermined intervals in the longitudinal direction. The grooves lO of the upper mold 2 and the lower mold 3 are arranged to face each other.

On the other hand, the first piston 5 is composed of a head 12 having a recess 11 formed in the center thereof, and a shaft portion 13 having a passage 7 inserted into the recess 11 . Accordingly, the outer circumferential wall of the head 12 is brought into closer contact with the inner circumferential wall of the vibrator 4 due to the pressure of the pressurizing fluid 6 press-fitted into the recess 11. In addition, the second piston 8
is a head 15 with a recess 14 formed in the center of the shank and a shaft 1
6, and the head 15 is the head 1 of the first piston 5.
Similar to 2, it is adapted to be in closer contact with the inner circumferential wall of the vibrator 4.

In order to mold a camshaft having a plurality of cams by the bulge processing method using each member of the above configuration, first the upper mold 2
and the lower mold 3, and insert the vibrator 4 into the respective housing recesses 9.Next, the first piston 5 and the second piston 8 are inserted into the vibrator 4 on the left and right sides using a drive means (not shown). Both pistons 5.8 are inserted into the respective openings, moved to a location corresponding to an arbitrary groove 10, and fixed at a position between the locations as shown in the figure.

In this state, the pressurized fluid 6 is force-fed from a conventional device (not shown) into the passage 7 of the first piston 5, and is injected into the pipe 4 through the passage 7. Then, vibrator 4
is bulged and deformed toward the groove lO of the upper mold 2 and lower mold 3 by the pressure of the injected pressurizing fluid 6, and a bulged portion 17 serving as a cam is formed on the outer peripheral surface.

Next, the first piston 5 and the second piston 8 are moved and fixed to locations corresponding to the other grooves 10 by the driving means, and the same operations as described above are repeated. A required number of bulges 17 are sequentially formed on the outer peripheral surface of the
Then, the camshaft is formed.

1 above, the wall invention described for one embodiment of the invention:
The present invention is not limited to the embodiments described above, and various modifications and changes can be made based on the technical concept of the present invention.

For example, in the embodiments described above, a case has been described in which a camshaft is molded, but it is also possible to mold other pond members.

e. Effects of the Invention - As described in F, the bulge processing method according to the present invention includes storing a cylindrical body in a mold having a plurality of concave grooves, and a second mold having a pressurizing fluid passage inside the cylindrical body. A first piston and a second piston disposed opposite to the first piston are slidably fitted, and both pistons are moved to a position corresponding to an arbitrary concave groove and fixed, and in this state, the process is performed. Pressurizing fluid is pressurized into the cylindrical body through the passage of the first piston, and the cylindrical body is deformed to bulge toward the groove by this pressure, and the cylindrical body is sequentially bulged on the outer circumferential surface of the cylindrical body. Since I tried to form the parts,
A large number of bulges can be formed using only one mold, improving work efficiency and reducing the number of molds.

Moreover, even when processing a part of a long cylindrical body, there is no need to increase the size of the mold itself to accommodate the cylindrical body, which is economically advantageous.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing a state in which a camshaft is processed by the bulge processing method according to the present invention, and FIGS. 2 and 3 are longitudinal sectional views showing the state in which a camshaft is processed by a conventional bulge processing method. be. DESCRIPTION OF SYMBOLS 1... Mold, 2... Upper mold, 3... Lower mold, 4... Pipe, 5... First piston, 6... Pressurizing fluid, 7... Passage,
8... Second piston, 9... Storage recess,
10...Concave groove, 17...Bulging part.

Claims (1)

[Claims] A divisible mold is provided with a storage recess for storing the cylindrical body, and a plurality of grooves are formed in the storage recess in the longitudinal direction at predetermined intervals, and a mold having a pressurizing fluid passage. 1
The cylindrical body is inserted into the mold using a piston and a second piston disposed opposite to the first piston at a predetermined distance, and the first piston and the second piston are inserted into the mold. Two pistons are slidably fitted into each piston, and both pistons are moved and fixed to a location corresponding to an arbitrary groove, and in this state, pressurizing fluid is supplied to the cylindrical shape through the passage of the first piston. A bulging method characterized in that the cylindrical body is press-fitted into a body to cause the cylindrical body to bulge and deform toward the groove, thereby sequentially forming a bulging portion on the outer peripheral surface of the cylindrical body.