Heating appts. for flexible mats, textiles, car seat covers, etc. - heats people individually to save energy by using textile-embedded heating wires each with two wires connected to DC voltage supply

摘要

The arrangement has heating wires connected to a voltage supply via control devices. Each heating wire consists of two closely-spaced sub-wires. The voltage source is balanced (=symmetric w.r.t. earth). The currents through the two sub-wires are also balanced and equal and opposite. The control devices connect the heating wires to the voltage supply via switches (21-22) controlled by clock pulses. The two sub-wires in each heating wire may take various forms, e.g. twisted and/or screened. The switches are electronic devices, e.g. FETs. The control devices may be smart power modules that include the switches. The d.c. voltage may be obtained from the a.c. mains by rectification. Monitors monitor balancing. USE/ADVANTAGE - As electric blankets, flying suits etc. Efficiency. Fault free.