Abstract: A stepping motor mechanism for a rotary device in which one member is indexed linearly and/or rotationally relative to a second rotating member. The indexing member includes at least one portion with a series of equi-distantly spaced ridges and the rotating member includes at least three ferromagnetic members adapted to rotate with the rotating member and spaced from one another, each of the ferromagnetic portions having defined thereon ridges complementary to the ridges on the indexing member but angularly or linearly displaced from one another. A fixed coil and coil carrier is positioned spaced from but adjacent to the ferromagnetic members such that as current is applied to the coils, a magnetic field is induced in the coil carrier and adjacent rotating ferromagnetic member thereby causing the ridges on the adjacent ferromagnetic member to align with the ridges defined on the rotating member.

Abstract: A sequentially operated machine employs two positionable members, a movable center selection piston member and a movable transducer member for accessing a record storage member selected by the central piston member. Making the record storage member available to the transducer reuires a predetermined time delay. Accordingly, the servomechanism powering the selecting mechanism has a high response, while a following servomechanism transporting the transducer has a low response such that cost is reduced while not adversely affecting access time to the record member.