Microphone shielding cover for telephone receiver handset - comprises tab-rotated grille whose holes can be aligned with holes in microphone cover, to selectively isolate microphone

摘要

A microphone (1) in a telephone handset (2) consists of a case (3) closed by a cover (4) with perforations (6) in its top. These allow the sound to reach the active part, which comprises a transducer (7) connected by finger contacts (8,9) and cable (10) to the handset base. Above the cover is a grille with perforations (12), which are arranged in an identical pattern to those of the cover. A pivot point (13) allows this grille to be rotated so that the perforations in the two elements can coincide. This allows the cover to be sealed or partially opened to the sound transmission. The rotation is effected by the user by slight rotation of a tail (16) attached to the grille and protruding through a slot (18).