JPS6360041A - Upset forming equipment for piston - Google Patents

Abstract

PURPOSE:To enable an efficient working by upset forming with a simple die composition in case of working a seal groove at the outer peripheral part of the skirt side of a piston. CONSTITUTION:When an intermediate die 2 is pushed by engaging a preform 4 with the outer die 1, the outer peripheral end part 4d at the opening side of the preform 4 is pressed by the intermediate die 2 and the wall of the opening side outer peripheral end part 4d is moved for the opening side inner peripheral end part 4e. According to the movement of this pressing wall a recessed groove is made to form near the opening side inner peripheral end part 4e by the inner die 3 which is engaged with the opening side inner peripheral part 2a of the intermediate die 2. Since the upset forming can be performed almost with a simple die composition the manhour in cutting can be curtailed.

Description

Detailed Description of the Invention (Field of Industrial Application) This invention relates to a piston crushing device,
The seal groove of the piston was devised so that it could be processed using a simple forming device using the upset method.

(Prior Art) As a conventional method for forming a seal groove in the outer peripheral portion of the skirt side of a two-stone, a method using a roll is known.

This method is superior in terms of strength because it does not cut the fibers formed by rolling the material, unlike the method in which the seal groove is carved out by cutting only, but it requires expensive rolls. The number of man-hours required for cutting is also increasing.

(Problem to be Solved by the Invention) For example, a boot groove for locking the boot of a piston of a wheel cylinder used in an automobile brake system is sufficient as long as it prevents the boot from coming off. Then, the depth of the groove can be as shallow as, for example, 1 column. Considering this, the conventional processing method of forming the boot groove by rolling, cutting, and grinding is excessively shallow. Therefore, it is necessary to devise a simple molding method and thereby reduce processing costs.

Therefore, this invention attempts to reduce the processing cost by making it possible to form 11=7 using a simple forming device and eliminating the need for cutting. 4 outer peripheral part 4a and outer bottom part 4
an outer mold 1 that is approximately tightly fitted into each of b, and the material 4 that is in the tightly fitted state;
The middle mold 2 is fitted onto the inner peripheral part 1a of the outer mold 1 on the opening side in order to press the outer peripheral end 4d of the opening side and move the pressed meat toward the inner peripheral end 4e of the opening side. In order to form a shallow concave groove 5 near the opening side inner peripheral end 4e as the meat moves,
This is a piston upsetting device comprising an inner mold 3 fitted to an inner circumference 2a on the opening side of a medium mold 2.

(Function) When the material 4 is fitted to the outer mold 1 and the middle mold 2 is pushed, the material 4
The opening-side outer peripheral end 4d of is pressed by the middle die 2, and the meat of the opening-side outer peripheral end 4d moves toward the opening-side inner peripheral end 4e.

With this movement of the pressed meat, a groove 5 is formed in the vicinity of the opening-side inner peripheral end 4e of the material 4 by the inner mold 3 fitted to the opening-side inner peripheral part 2a of the medium mold 2. .

(Example) Next, an explanation will be given based on one embodiment of the present invention.

A hollow cylindrical outer part 1 whose longitudinal cross section is shown in FIG. A large diameter part 3a that can be fitted almost tightly into the opening side inner peripheral part 2a of the medium 2, a cylindrical small diameter part 3b having a smaller diameter than the large diameter part 3a, and a cheek part that connects the large diameter part 3a and the small diameter part 3b. An upsetting mold consisting of an inner mold 3 having 3C parts is used. The unheated pit-shaped material 4 shown in FIG.
When the small diameter part 3b of the inner mold 3 is fitted into the inner peripheral part 4C of the inner mold 3 and the medium mold 2 is pushed in the arrow direction in FIG. The meat near the opening-side outer circumferential end 4d is pushed by and the pushed-in meat moves toward the opening-side inner circumferential end 4e,
An opening side edge 4f that is thinner and protrudes than the opening side outer peripheral end 4d is formed.

Since this opening side edge 4f hits the chain part 3C of the inner mold 3 and receives a force directed outward from the outer periphery, a groove 5 illustrated in FIG. 1 is generated, and the molding is completed. Sometimes, as shown in FIG. 4, a ring-shaped groove 5 is formed near the open end 6a of the piston 6.

The outer mold 1 in the illustrated example is configured such that its bottom portion 1b can be separated from the main body IC, and when molding is completed, the bottom portion 1b is separated from the main body IC, the rear end of the outer mold 1 is opened, and then the inner By largely pushing the mold 3 in the direction of the arrow in FIG. 1, the piston 6 is removed from the mold. The molded piston 6 has the concave groove 5 finished by, for example, grinding.

The material 4 used is one shaped into a two-piece shape by hot working.

(Effects of the Invention) The piston upsetting device according to the present invention is constructed as described above, and includes a material 4 fitted to an outer mold 1 and a middle mold 2
When you push , the opening side outer peripheral end 4d of the material 4 moves to the middle size 2.
, the flesh of the outer circumferential end 4d of the opening grate 11 moves toward the inner circumferential end 4e on the opening side.

With this movement of the pressed meat, a shallow groove 5 is formed near the opening-side inner peripheral end 4e of the material 4 by the inner mold 3 fitted to the opening-side inner peripheral part 2a of the medium mold 2. According to the present invention, the desired piston 6 can be formed using a simple structure such as the outer mold 1, middle mold 2, and inner mold 3, the equipment cost is low, and the piston 6 can be formed into a desired piston 6 by using a cutting process such as a concave groove molding. This eliminates the increase in processing costs and achieves highly efficient molding.

[Brief explanation of drawings]

The figures show an embodiment of the present invention, and FIGS. 1 and 2 are longitudinal cross-sectional views of the molding device in its respective states, and FIG.
FIG. 4 is a longitudinal cross-sectional view showing each of the Nogistone products. 1... Outer mold, l a , 2a... Opening side inner peripheral part,
2...Medium size, 3...Inner mold, 4...Material, 4a...
- Outer peripheral part, 4b...outer bottom part, 4d...opening side outer peripheral end, 4e...opening side inner peripheral end, 5...concave groove.

Claims (1)

[Claims] An outer mold that fits substantially tightly into each of the outer periphery and outer bottom of the pot-shaped material, and the outer periphery end on the opening side of the tightly fitted material is pressed toward the inner periphery end on the opening side. A medium mold is fitted to the inner periphery on the opening side of the outer mold to move the meat, and an inner periphery on the opening side of the medium mold is fitted to the inner periphery on the opening side to form a shallow groove near the inner periphery on the opening side as the pressed meat moves. A piston upsetting molding device consisting of an inner mold fitted into a piston.