DE911571C - Process for the production of die forms, in particular by cold countersinking - Google Patents

Description

Process for the production of die forms, in particular by cold countersinking The invention relates to a method for the production of die forms., In particular by cold countersinking a preferably metallic workpiece that is produced during pressing is set in resonance vibrations.

It is known per se to remove workpieces during deformation by tensile, To put pressure or thrust forces in a forced oscillation. In one proceeding in this way it is proposed to set the workpiece in resonance vibrations, which correspond to a harmonic of the 'workpiece. This is called a body of revolution trained workpiece vibrated at high speed, so that the centrifugal forces act as additional deformation forces. According to the invention is used in a method for the production of die forms, in particular by means of cold countersinking one. preferably metallic workpiece, which during pressing ün resonance vibrations is offset, the workpiece is designed as a clay mushroom and by exciting its end faces set in resonance vibrations in this way, i.e. in the middle where the die is pressed in will result in large pressure amplitudes.

In a preferred arrangement for implementing the inventive concept the resonance excitation takes place at a low frequency of, for example, 100 Hz or Grid frequency.

The design of the workpiece specified according to the invention and the application lower frequencies have the significant advantage that the equipment can be set up very simply to generate the vibrations. It consists in In this case from the vibration generator - a suitably constructed electromagnet can be, and a converter of corresponding power.

In order to carry out the invention, the excitation for oscillation takes place advantageous so that the end faces of the clay mushroom vibrate against each other. the Vibration is generated by electromagnetic excitation of a ferromagnetic or magnetostrictive material produced by existing clay mushrooms. The frequencies of the the workpiece stimulating vibrations can be regulated so that always the exact Resonance frequency can be maintained.

In the following the invention with reference to the accompanying drawing explained. "Cold sinking" is described as an example. Naturally the method according to the invention can also be used for hot forming. Here, however, are the upper temporal limits, the area of application for the Procedure determined by the Curie point of the particular material used. the The position of the Curie point itself depends on the composition of the material, especially with alloyed iron types.

According to the drawing, i should be in the middle part of the workpiece Die form are pressed in. The workpiece i is designed as a clay mushroom. A clay mushroom is an oscillation structure with two masses, which are essentially different from the one connecting them Elasticity are separated. It represents the coupled oscillation structure, that are most easily excited to resonance vibrations with low energy can. After completion, the ends of the workpiece i are cut off, since only the middle part with the pressed-in die should be used. This Part rests on the counter bearing .2, which during pressing the high pressure of one hard material existing sinking punch 3 must take up. According to the drawing the die 3 already has one. Impression 4 generated in the workpiece.

At both ends of the workpiece i. Is a vibration generator Electromagnet 6 attached, when energized with an alternating current suitable frequency the workpiece vibrates.

In each of the end faces of the workpiece is a package 5 of laminated High permeability iron embedded and screwed. This laminated core forms the armature 5 of the electromagnet 6 with the winding 7. The magnetic cores are e.g. E-shaped. Both magnets 6 are mounted on a strong mounting bracket .8, which should vibrate as little as possible when the magnets are excited.

The magnets 6 are so to achieve the highest possible effect excited that their facing surfaces vibrate against each other, which is caused by In-phase excitation of the magnet windings 7 is achieved. The anchor 5 and therefore the clay mushrooms are now set in vibration by the electromagnets6. at Resonance excitation vibrate the end faces 9 of the Tonpilze, s with a large amplitude. In the middle of the workpiece i, where the die is pressed in, large ones are created Pressure amplitudes and correspondingly large forces. It is through these forces that the process becomes when pressing the die, it is greatly facilitated and accelerated.

The arrangement is with a not shown and known per se Device for regulating the frequency provided so that always the exact resonance frequency of the workpiece i designed as a clay mushroom can be complied with.

Claims (5)

PATENT CLAIMS: i. Process for the production of die molds, in particular by cold countersinking a preferably metallic workpiece that is produced during pressing is set in resonance vibrations, characterized in that the workpiece is designed as a clay mushroom and so in resonance vibrations by exciting its end faces is offset that in the middle where the die is pressed in, large pressure amplitudes develop. 2. Arrangement for performing the method according to claim i, characterized characterized in that the resonance excitation with a low frequency of for example a few hundred hertz or network frequency. 3. Arrangement for the implementation of the Method according to claim i or 2, characterized in that the excitation for Vibration takes place in such a way that the end faces of the clay mushroom vibrate against each other. 4. Arrangement according to claim 2 and 3, characterized in that the vibrations by electromagnetic excitation of a ferromagnetic or magnetostrictive Material existing clay mushrooms can be produced. 5. Arrangement according to claim i to 4, characterized in that the frequency of the vibrations exciting the workpiece can be regulated in such a way that the exact resonance frequency is always maintained.