SU1761390A2 - Device for stress concentrating deposition - Google Patents

Abstract

Use: Apply a stress concentrator to the workpiece for subsequent separation. SUMMARY OF THE INVENTION: The device comprises a high-frequency electric generator to which a single-turn inductor is connected, having a narrowed cross-sectional area and a ferromagnetic element installed in the zone of this area of the inductor. The ratio of the width of the inductor to the width of its narrowed area lie in the range of 5-15. 1 il.

Description

The invention relates to the processing of metals by pressure, can be used in the blank production, and is an improvement for the application of a stress concentrator according to the author. No. 1696184.

The device for applying a stress concentrator comprises an electric generator, an inductor having a narrowed cross-sectional area and a ferromagnetic element mounted in the zone of this inductor.

The disadvantage of the device is low work efficiency, namely low efficiency, productivity and efficiency of formation of the concentrator. The first two factors of work efficiency decrease as a result of the lack of a choice of the ratio between the width of the inductor and the width of its narrowed portion. As a result - significant heating of the surface of the workpiece under the wide part of the inductor. This leads to the fact that energy is expended here, which reduces efficiency, and the time increases

heating the surface of the workpiece under the narrowed part of the inductor, which reduces the performance of the operation. The presence of unproductive energy costs and an increase in the time of the heating process lead to the spread of heat in the zone of application of the intended concentrator. As a result, the temperature gradient levels out and the formation efficiency of the concentrator drops.

The object of the further invention is to increase efficiency by increasing productivity and efficiency.

This goal is achieved by the fact that in a device for applying a stress concentrator, containing a tool for creating a stress concentrator, made in the form of a high-frequency electric generator, a single-turn inductor having a narrowed cross-section and a ferromagnetic element mounted in it this section of the inductor, relative (L

WITH

vi o

with che about

Yu

The inductor width to width of its narrowed portion is 5 ... 15.

The drawing shows a device for applying a stress concentrator.

The device for applying a voltage concentrator contains a high-frequency electric generator 1 to which a single-turn inductor 2 is connected, for example an annular form (drawing). Inductor 2 has a conductor with a part 3 of constant width and a narrowed part 4. In the zone of which the ferromagnetic element 5 is located. The ratio of the width of part 3 to the width of part 4 of inductor 2 lies in the range from 5 to 15. A workpiece 6 is placed inside inductor 2, on the surfaces of which it is necessary to apply a stress concentrator against narrow part 4 and inductor 2.

The device works as follows.

When electric current flows through the inductor 2 after switching on the generator 1, the current density in the preform b is unevenly distributed. Against the narrowed part

4 inductor 2 on the surface of the workpiece b, the maximum current density is observed, which provides greater heating of this surface area of the workpiece 6. Due to the choice of the ratio of the widths of parts 3 and 4 of inductor 2, heating of the part of workpiece 6 lying against part 4 of inductor 2 goes

with high speed. In this case, the portion of the preform lying against the part 3 of the inductor 2 is heated slightly. In addition, due to the presence of a ferromagnetic element

5, there is an uneven heating of the surface in the area of the workpiece 6 against the part 4 of the inductor 2 along the generator of the workpiece 6. After the heating is stopped due to disconnection

Generator 1 as a result of different cooling rates of the locally heated surface of the workpiece 6, namely its middle part, opposite the center line of the narrow part 4 of the inductor 2, in this zone a crack forms along the perimeter, which is a sharp stress concentrator upon further breaking the workpiece into press (not shown).

Claims (2)

A decrease in the ratio of the widths of parts 3 and 4 to less than 5 leads to a decrease in the efficiency of the device, since as a result, the energy coming from the generator 1 to heat up begins to be redistributed, so that the heating rate of the surface of the workpiece 6 is reduced. and increases the temperature of the heating surface of the workpiece 6, which lies against part 3 of the inductor 2. These factors immediately begin to affect the efficiency of the formation of the concentrator. The latter either does not form or does not form over the entire surface, depending on the degree of decrease in the ratio of the widths of parts 3 and 4. Increasing the ratio of the widths of parts 3 and 4 of inductor 2 by more than 15 is impractical, since the effect remains unchanged, and the consumption of the material from which the inductor is made increases, which causes an unjustified increase in the cost of equipment, its size and weight. The invention The device for applying a stress concentrator according to the author. No. 1696184, about the fact that. in order to increase efficiency by increasing productivity and efficiency, the ratio of the width of the inductor to the width of its narrowed portion is 5-15.