RU2255826C2 - Forming apparatus - Google Patents

Abstract

FIELD: plastic working of metals, possibly manufacture of parts with variable wall thickness from sheet blanks.

SUBSTANCE: forming apparatus includes die and sectional punch and in addition it includes support arranged over die. Between die and said support gasket is placed with possibility of changing it. Central punch has axial recess for placing buffer gasket having plug or draw plate overlapping it in order to provide desired resistance of buffer gasket to metal flowing process.

EFFECT: possibility for forming large size parts at high accuracy.

1 dwg

Description

The invention relates to the field of metal forming and can be used in all engineering industries to obtain parts from sheet materials with a variable wall thickness.

A device for stamping thin-walled ends of large diameter for pressure housings, which contains a matrix with an insert, the workpiece holder and telescopic punches, as well as the lower matrix. The known device is intended for the manufacture of parts with the same thickness throughout the part (UK Application No. 1438207, IPC B 21 D 22/12, publ. 06/03/76. "Device for stamping thin-walled ends of large diameter for pressure casings").

Closest to the proposed device relates to a device for sectional stamping, which includes a sectional punch and a die. On the known device, the workpiece is deformed sequentially in separate annular sections (E.I. Semenov “Forging and Die Forging” Moscow, “Higher School”, 1972, p.142). The disadvantages of this device include the low accuracy of the stamped parts. After sectional stamping, mechanical refinement of the manufactured part is required.

The problem solved by the invention is the development of a device on which it is possible to stamp large-sized parts with high accuracy on relatively low-power and small-sized universal presses, which are widely used in industry. The efforts developed by these presses are quite acceptable for the long-term operation of die tooling.

The technical result obtained by using the present invention is to be able to stamp large products with an accuracy of at least 9 degrees according to ST SEV 144-75.

The solution to this problem lies in the fact that in the proposed device, as well as in the known one, containing a matrix and a sectional punch, it is provided to additionally introduce a support and place it above the matrix, while it is proposed to install a gasket between the matrix and the support, which should be replaced at subsequent transitions with gasket of a different thickness. A recess is made along the axis of the central punch, in which a buffer gasket with a cap overlapping it is placed. The plug used after the first transition has a central through hole.

The drawing shows a device for stamping, a stamp is indicated to the left of the center line, the details of which occupy a position at the end of the first transition, and a stamp is indicated to the right of the axial line, a stamp whose parts occupy a position at the end of the second transition, where 1 is a matrix, 2 is a gasket for the first transition , 3 - support, 4 - centering sleeve, 5 - plug, 6 - die, 7 - punch-sleeve, 8 - gasket for the second transition, 9 - buffer gasket, 10 - central punch, 11 - stamped part (shell).

A blank 11 is placed in the matrix 1. A recess is made along the axis in the central punch, in which a buffer gasket 9 is placed with a cap 5. The gasket 2 is installed between the support 3 and the matrix 1, which is replaced by a thinner one at subsequent transitions.

The stamping process proceeds as follows. A blank 11 is installed in the matrix 1. At the first transition, the blank is deformed by a central punch 10, which is centered by a sleeve 4. A buffer strip 9 made of aluminum AD1 or the like. and installed in the Central recess of the punch, block the plug 5, which prevents the leakage of the buffer strip 9, which transfers the stamping force from the support 3 to the punch 10. The thickness of the strip 2 provides the stroke size of the punch for the first transition.

For the second transition, instead of gasket 2, gasket 8 is installed.

The method is carried out in three transitions as follows. Using a sheet blank, the first transition is performed, for the implementation of which a buffer pad 9 is made of aluminum AD1, A5 or the like. and interacting with the central punch 10, install a plug 5, which prevents the leakage of aluminum buffer strip. Install the gasket 2, the thickness of which provides the magnitude of the stroke of the punch for the first transition. The sleeve 4 centers the punch 10. During the first transition, the punch 10 is introduced into the stamped part (shell) 11. At the first transition, the buffer strip 9 serves to transfer the stamping force from the support 3 to the punch 10. In the drawing to the left of the center line, the stamp is indicated, details which occupy a position at the end of the first transition.

To perform the second transition, instead of the gasket 2, a gasket 8 of a smaller thickness is installed, which provides the required stroke of the punch-sleeve 7. Instead of the plug 5, the die is installed 6. The centering sleeve 4 is removed and the punch-sleeve 7 is installed instead. the punch-sleeve 7 is introduced, while the force of pressing the punch 10 against the stamped shell 11 should provide two conditions:

1) the punch should remain motionless relative to the stamped shell (not penetrate into it);

2) the punch should be pressed against the stamped shell with such a force that the shell material does not flow under the punch.

The force of pressing the punch 10 to the stamped shell 11 corresponding to the above conditions is provided by the resistance value of the buffer strip 9 when it expires through the die 6.

The third transition of the stamping operation is performed similarly to the second, namely, instead of the punch 10 with the punch-sleeve 7, a punch is installed, the outer diameter of which is equal to the outer diameter of the punch-sleeve 7. In order to perform the third transition, a second punch-sleeve is installed, the gasket 8 is removed and a new one is installed buffer pad. During the third transition, the punch also remains stationary relative to the stamped shell.

The final design of the shell occurs due to movement under the action of the press force of the second punch-sleeve relative to the stamped shell.

Claims (1)

A stamping device comprising a die and a sectional punch, characterized in that the device further comprises a support located above the die, wherein a gasket is installed between the die and the support with the possibility of its replacement, and a recess is made on the central punch along the axis, in which a buffer gasket is installed with a cap or die overlapping it, providing the required resistance to the process of expiration of a buffer strip through it.