Abstract: A stator for a stepping motor, the stator having a plurality of salient poles and at least two windings, each winding comprising at least two conductors each of which is wound upon one or more separate poles. The conductors of each winding may be connected either in series or in parallel. This winding arrangement is particularly advantageous when the conductors of each winding are connected in series and driven with a bipolar drive, as problems which exist with bifilar windings, such as high conductor-to-conductor potentials and inductive spikes, are avoided.

Abstract: An up/down counter interface converts input information suitable for the operation of one type up/down counter, which type receives input information in the form of a direct current logic signal indicating direction and a train of electric pulses representing increments of information, to input information suitable for the operation of a second type up/down counter, which second type receives input information in the form of two identical pulse trains representing increments of information, direction being determined by the relative displacement in time of the two pulse trains.

Abstract: An adjustable voltage transformer having a commutating surface formed of segments of electrical conductors upon which a contact brush is movable while in electrical engagement therewith. Means are provided to "step" the brush between segments, so that when at rest, the brush contacts no more than one segment, thus reducing short-circuiting currents and overheating; however, when the brush is being moved, it is in contact with two segments, thus allowing uninterrupted output from the transformer.

Abstract: A coil for a variable transformer is provided having multiple layers of wire. Winding of such a coil is facilitated by providing an end form having a series of raised fins, or partitions, between which stacked layers of wire are held. The construction provides for easy and economical machine-winding and ensures that the segments of wire forming the commutating surface are held relatively immovable with respect to each other, thus preserving the integrity of the commutating surface.

Abstract: The Detector Module derives a synchronization signal from the half-wave crossovers of the AC power line. A half-wave peak detector detects the peak voltage of each half wave. An impulse detector detects the voltage of any impulses occurring during a half-wave. A common mode detector detects the peak value of each half-wave across the common mode terminals. A microcomputer is provided together with a clock/calendar for recording threshold values and for each half-cycle if a SAG or SURGE is detected; the time that the SAG or SURGE was initiated; the voltage of the half cycle of greatest SAG or SURGE during the event and the number of cycles is recorded. For LO and HI AVERAGE an average resistor stores the average of the peak values for each of the last thirty-two half cycles and that average is compared with the threshold to determine if an event has occurred. If an event has occurred, the duration and the lowest average occurring during the event is stored.

Abstract: A method and system for controlling a digital motor to allow operation in a microstepping mode at low velocities where microstepping is advantageous and to allow operation in a non-microstepping mode at high motor velocities to take advantage of the higher torque attainable. The transition from microstepping to non-microstepping or from non-microstepping to microstepping is accomplished free of velocity perturbations in the motor phases.

Abstract: An electromagnetic device of the type having a rotor and a stator with magnetically coacting peripheries, with the stator having toothed pole structures, has the stator pole teeth set at nonuniform spacing to improve the operating characteristics of the device. When the device is a stepping motor, improved step accuracy is attained through reduction of residual (or detent) torque. Reduction of airborne noise is reduced in all motor types.

Abstract: An improved electrical device of the type having a coil and a base and having a thermally conductive electrical insulating material placed between the coil and the base so as to facilitate the flow of heat from the coil to the base, and further having a base with an extended surface area so as to promote the flow of heat from the base to the surrounding air. In one construction, the insulating material is cast in place, thus cementing the coil and the base together.

Abstract: An overcurrent detection and protection device for stepping motors has means for detecting an overcurrent condition in the power supply to a stepping motor. Means responsive to the detecting means rapidly provides a signal to the stepping motor drive system causing the current to terminate and to remain terminated for a predetermined interval of time, at the end of which interval the device resets itself causing the current to resume. The device is sufficiently fast-acting to protect electronic components such as transistors.

Abstract: The rotor in each of the disclosed stepping motors comprises a permanent magnet disc between toothed pole pieces, the diameter of the magnet disc is essentially equal to the outer diameter of the toothed pole pieces.

Abstract: The disclosed stepping motors have a toothed rotor surrounded by a stator having poles extending toward the rotor, and coils on the poles. At one end of the stator, serial connections between the coils are held at safe positions by detent portions of an annular insulator. Those connections are laid into the detents during the winding process.

Abstract: A bobbin wound stepping motor has a stator formed of a plurality of stamped metal pieces that are concentrically secured together by projection welding through the use of an arbor except for its rear plate which is positioned concentrically by locating holes and half-blanks and secured in the assembled motor by push nuts after insertion of the rotor.

Abstract: In the disclosed electro-mechanical system of a stepping motor and its control circuit, positive electrical damping is provided for avoiding loss of synchronism and loss of torque over the range of intermediate and high stepping frequencies by imposing a self-adjusting limit on the motor current over a period of time longer than any prominent period of parametric oscillation of the system and supplying current to the motor with a d-c supply having high impedance.

Abstract: A power control unit causes a high supply voltage to be intermittently chopped to provide energy pulses in a core transformer and the energy in the core is discharged into a capacitor with the capacitor constituting the power source for a stepping motor and with the extent of the energy pulse accepted by the capacitor being determined by the condition of the capacitor which in turn is set by the instantaneous operating state of the motor.

Abstract: A stepping motor control circuit that had accepted manual adjustments for setting the stepping rate and direction of rotation of a stepping motor is made to have its stepping rate and direction controlled by the value of an analog command voltage.

Abstract: A test probe for providing a releasable tensioned electrical connection to a selectable part or component of a printed circuit board by either hooking a wire or component lead with the probe end or inserting the probe end into an aperture of a test terminal.

Abstract: Lead wires of a motor are stapled to a somewhat rigid, insulating disc to have their stripped ends be at selected points on the disc, the ends of the motor windings are placed in selected slots adjacent the stripped ends and wrapped thereabout and then soldered thereto to interconnect the winding ends with the appropriate lead wires, another insulating disc is positioned over the first and push nuts secure the assembly to the stator.

Abstract: A regulator for providing two different steps of bucking and two different steps of boosting correcting voltages to maintain the value of its output voltage within a selectable range with the regulator effecting each step correction for the next half-cycle based on the peak output voltage of the last half-cycle.