Patent ID: 11957943
Assignee: SIEMENS SCHWEIZ AG
Field: Environmental technology (Chemistry)
Classification: CPC A | IPC A

Claim 13:
14. A method for blocking a drive direction of a drive element for a fire damper, the method comprising:
arranging a wrap spring around a drive shaft driven by a drive unit;
prestressing the wrap spring using a thermocouple;
wherein the thermocouple, in the event of a fire or in the event of overheating of a machine, decreases in strength or melts, with the prestressed wrap spring relaxing as a result;
wherein a material of the thermocouple has a lower melting temperature compared to a melting temperature of the wrap spring;
wherein the relaxed wrap spring has a smaller internal diameter than the prestressed wrap spring;
wherein the wrap spring, due to the reduced internal diameter, blocks rotation of the drive shaft in the drive direction, and allows it in an opposite direction of rotation.