DE8902460U1 - High voltage transformer - Google Patents

Description

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BOSCH-SIEMENS HOUSEHOLD APPLIANCES b'GMB« ^{v 5 ;} ■ ^; ßdOO -Munich 80, 20.02.1989

Hochstrasse 17

TZP 89/603 Thi/hü

High voltage transf crraaro r

The innovation relates to a high-voltage transformer which is particularly suitable for supplying a magnetron, whereby the magnetron generates high-frequency energy that is used in a household appliance for cooking, roasting or baking.

High-voltage transformers, generally consisting of a primary winding, a heating winding and a secondary winding, are required in household appliances operated with microwave energy to generate the heating voltage for the magnetron cathode and to generate the magnetron operating voltage. The maximum operating voltage is around 4 kV. This value can be significantly exceeded for switch-on voltage peaks. For microwave household appliances, the aim is to have the most efficient cooking chamber possible, so that the space available for the necessary electronic components is calculated. The high-voltage transformer is located close to the side wall of the appliance for operational reasons. If high levels of power are switched on or off, bang effects occur due to the switch-on voltage peaks.

The aim of the innovation is therefore to prevent the bang effect with simple measures. The arrangement according to the invention for solving this problem is characterized in that the high-voltage transformer is arranged in front of a side wall of the household appliance with a safety distance dependent on the field strength. An advantageous embodiment of the innovation is characterized in that the secondary winding of the high-voltage transformer attached to a mounting plate

TZP89/603

is arranged between the primary winding and the side wall. Further advantageous designs of the innovation are contained in the subclaims. An embodiment of the innovation is described in more detail below with reference to the drawing. It shows:

Fig. 1 a bang-free arrangement of the high-voltage transformer

Fig. 2 shows an arrangement of the high-voltage transformer at risk of explosion.

According to Fig. 1, a high-voltage transformer 1, consisting of a primary winding 2, a heating winding (not shown) and a secondary winding 3 is arranged opposite a side wall 4 and fastened to a mounting plate 5. The secondary winding 3 is located between the primary winding 2 and the side wall 4. This creates the necessary field strength-specific safety distance, with the secondary winding 3 developing a shielding effect of the side wall 4 by absorbing field energy.

Fig. 2 shows a structurally favorable arrangement, which is, however, susceptible to explosions. The primary winding of the high-voltage transformer is arranged opposite the side wall 4. When voltage peaks occur, a field strength so great that explosions develop via the side wall 4 can be achieved. This is particularly the case because the arrangement of the secondary winding does not provide any shielding effect with regard to the explosion effect with the side wall 4.

Claims (3)

TZP89/603 &Lgr;&eegr; s &rgr; r ü c he 1. High voltage transformer, particularly suitable for feeding a magnetron, whereby the magnetron generates HF energy which is used in a household appliance for cooking, roasting or baking, characterized in that the secondary winding (3) of the high voltage transformer (1) fastened to a mounting plate (5) is arranged between the primary winding (2) and the side wall (4). 2. High-voltage transformer according to claim 1, characterized in that the high-voltage transformer (1) is arranged in front of a side wall (4) of the household appliance with a field strength-dependent safety distance. 3. High-voltage transformer according to claim 1, characterized in that the distance from the primary winding center to the side wall (4) is greater than 8 cm.