Patent ID: 11961379
Assignee: SIEMENS SCHWEIZ AG
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 0:
1. A method for producing a cylindrical measurement chamber for a smoke detection unit of a smoke detector, the method comprising:
forming a measurement chamber cover using an injection molding process;
combining the measurement chamber cover with a complementary, essentially hollow or hollow cylindrical smoke inlet part to make up the measurement chamber;
wherein the measurement chamber cover comprises a spherical component with introduced angular concentric light trap structures shaped to form Fresnel light trap structures following the compact-design principle of a Fresnel stepped lens;
wherein the Fresnel light trap structures of the spherical measurement chamber cover, after the injection molding process, are free of undercuts;
wherein the spherical measurement chamber cover is formed into an essentially flat measurement chamber cover using a deformation process;
wherein the Fresnel light trap structures are shaped in the direction of the Fresnel axis and undercuts form;
wherein a Fresnel point, after the measurement chamber as a whole has been produced and after it has been attached to a smoke detection unit provided, is located at a light exit of a light emitter of the smoke detection unit.