Locking pawl for telephone dialling switch - has follower pawl on dialling disc, protruding into annular space between ring inner toothing and follower disc

摘要

The dialling switch has a follower disc, rotating with it both during selection and the dial resetting run. The disc follower pawl is out of contact with the inner toothing of a concentric toothed rim during dialling, while during resetting run engaging the inner toothing. The outer toothing of the rim drives a pulsing cam disc. The follower pawl (4) is loosely mounted in a recess of the dialling switch disc (2). It protrudes into an annular space between the periphery of the follower disc and the inner toothing (9) of the toothed rim (3). According to the direction of rotation of the follower disc it is pressed against, or lifted from, the inner toothing of the rim. This actuation is carried out by switching cams (6) of the dialling switch disc, mounted concentrically to the follower disc. The switching cams are formed by both ends of an arcuate switching strip, which provides radial guide for the dialling switch disc along the inner toothing of the rim.