Tion device for stopping a rotating member at a predetermined angular posi

Claim 1

Apparatus for stopping a rotating member at a predetermined angular position, comprising: a rotating member; high speed driving means for driving said rotating member at a high speed; low speed driving means for driving said rotating member at a low speed lower than said high speed; drive selector means for selecting between said high speed and low speed driving means; brake means for acting on said low speed drive means; rotational position detecting means, including magnetic means rotating with said rotating member and a pair of coils in which pulse voltages are induced by said rotating magnetic means, said pair of coils being spaced apart a predetermined rotational angular distance from each other; a bi-stable multivibrator, the inputs of which are connected to the outputs of said pair of coils; first switching means connected to the output of said bi-stable multivibrator, said switching means being operated by the output of said bi-stable multivibrator; a charged circuit including a resistor and capacitor connected in series, said charged circuit being connected in parallel with said first switching means through a normally open relay contact; an electromagnetic relay having a plurality of contacts including said normally open contact and a magnetic coil connected in series with said charged circuit; at least one of said relay contacts being connected in the Power circuit of said low speed driving means; another of said relay contacts being connected to said brake means to control the operation thereof; and second switching means connected across said charged circuit and being connected to and operated by said drive selector means.