Abstract: A rotary pulse generator is disclosed for attachment to a rotary machine, such as a motor, having a rotary shaft extending therefrom. The generator includes a rotor which is secured to the shaft for rotation therewith. The rotor has a circumferential surface carrying an annular periodic pulse generating pattern, such as a magnetic pattern. A stator housing is secured to the machine. The stator housing carries a stator assembly including a sensor which is spaced radially from the rotor by a sensor gap. The sensor senses the pulse generating pattern and serves to provide pulses or the like having a frequency related to the angular velocity of the rotor. The sensor assembly includes a support block and a sensor support mounted to the support block for movement relative thereto between a retracted position located away from the rotor and a contact position wherein the sensor block contacts the rotor.

Abstract: Apparatus is presented for controlling the duty cycle of a pulse generator which provides a periodic input signal having a frequency proportional to the rate of movement of an input member. The input signal is compared with a threshold signal and, for each cycle of the periodic signal, an ON signal is provided so long as the magnitude of the input signal exceeds that of the threshold signal. The apparatus for controlling the duty cycle includes a clock source for providing clock pulses having a fixed frequency rate. A first counter counts the total number of clock pulses occurring during an interval corresponding with N of the ON pulses to provide a total count of B. A second counter counts the total number of clock pulses occurring during each of the N ON pulses and provide a total count of A. The ratio of A to B is calculated to provide a ratio R.

Abstract: Apparatus and method are disclosed for testing winding terminations and more particularly for testing armature winding termination continuity. A nonrotating, simultaneous test is made of the armature winding terminations to commutator bars by simultaneously applying equal currents to different sets of bar-to-bar winding terminations. The differences in the bar-to-bar voltages of selected pairs of bar-to-bar terminations are obtained and a determination is made as to whether any voltage difference exceeds a reference limit. If not, then an acceptable continuity test indication is given.

Abstract: Apparatus and method for testing windings, as for determining proper winding connections, by sensing the magnetic fields produced at the windings when energized by a time varying signal. Output signals are produced in dependence upon the polarity or direction of the magnetic fields. These signals are compared with a clock signal synchronized to the energizing signal to obtain an indication as to the phase relationship of the magnetic fields.