Plug-type switch

Claim 1

An electric power supply operated switch clock for an appliance plug, comprising a housing, constant speed drive motor means in said housing, a plug head mounted in said housing adjacent a back wall thereof and centrally located in said back wall having pin contacts adapted to be engaged in the power supply and being connected to said drive motor means, a plug socket in said housing coaxial with and spaced from said plug head adjacent an opposite front wall of said housing having pin bushings axially aligned with said pin contacts and a socket cup having an opening in said front wall for receiving the appliance plug, a switch ring rotatably mounted in said housing coaxially disposed about said plug socket for timed rotary movement about said plug socket connected to said drive motor means for rotation thereby, a quick-break switch gear in said housing outside said switch ring including at least one pair of switch contacts connected between at least one of said pin contacts and at least one of said pin bushings, said switch ring having an annular shoulder with a plurality of switch rider receiving bores which are angularly equidistantly spaced from each other in said annular shoulder, at least one switch rider in at least one of said receiving bores, said quick-break switch gear having a switching element disposed in the path of movement of said at least one of said switch riders for actuation of movement of said switch rider with said switch ring to make and break contact between said pair of switch contacts, said housing being substantially square in shape with the diameter of said switching ring being slightly smaller than the length of a side of said housing, said drive motor means including a synchronous motor, a timer mechanism having a pinion gear connected between said synchronous motor and said switch ring to rotate said switch ring at a constant timed speed and accommodate it in said housing between said plug head and said plug socket and connected between said plug head and said plug socket, a substantially cylindrical guide body located within said switch ring and connected thereto and extending axially beyond each end thereof with one end portion having a toothed rim engaged with said pinion gear of said timed mechanism and its opposite end portion having an outer grip surface, said housing including a partition wall with a circular rib extending therefrom, said switch ring engaged over and guided for rotation on said rib and said cylindrical guide body engaged around and guided for rotation on said socket cup, said synchronous motor, timing mechanism and quick-break switch gear being disposed around said plug socket in said housing.