Abstract: An improved electronic proximity sensor and crack detector that is primarily responsive to the induced resistance in a coil; including an LC resonating circuit that utilizes constant current and a DC power source. By sensing changes in the induced resistance, the invention detects various conditions of parts present and probe fault and can detect a crack in a rotating metal object that is in proximity with the probe. This is accomplished by sensing changes in the induced resistance that occur at the same frequency at which the metal object is rotating.

Abstract: A combination of a programmable logic controller with analog circuitry. The analog circuitry includes a summation point to which several items are coupled. Analog inputs are selectively coupled to the summation point through analog switches. Also, the output of a digital to analog converter couples to the summation point. Still further, the analog output for the controller is obtained from a sample and hold circuit which has its input connected to the summation point and which includes means for outputting the analog value at its output back to the summing point. Even still further, a comparator input couples to the summation point. The arrangement provides for direct processing of analog information either by direct output of analog processed analog data or by obtaining one bit data from the comparator which represents whether a threshold has been reached by the analog data.

Abstract: An induction motor circuit which effectively prevents voltage spikes caused by leakage inductance of the induction motor stator windings without otherwise interfering with the overall operation of the induction motor. The circuit incorporates two windings between a common point and the positive supply and two other windings between the common point and the negative supply. Voltage spikes are suppressed by diodes connecting directly from the ends of each of the windings to the supply terminals oriented to the opposite end of the respective windings.

Abstract: A transformer-coupled isolation amplifier which has a minimally sized transformer, high common mode rejection, and a highly linear response over a wide dynamic range. A first chopper periodically alternates by 180.degree. the connection of the input through a high resistance to the primary of a small square loop pulse transformer. The secondary, with the end of the winding closest to the primary grounded, has the inputs of an operational amplifier placed across it. Negative feedback is provided around the amplifier to provide an apparent very low impedance across the secondary of the transformer. The negative feedback induces a current in the transformer secondary which cancels the flux produced by current flowing in the primary, thereby allowing usage of the transformer normally suitable only for high speed pulses. The output of the amplifier connects to a second chopper synchronous with the first to generate the amplified analog signal.

Abstract: A circuit which effectively prevents voltage spikes caused by leakage inductance of the step motor windings without otherwise interfering with the overall operation of the step motor. The circuit incorporates two windings between a common point and the positive supply and two other windings between the common point and the negative supply. Voltage spikes are suppressed by diodes connecting directly from the ends of each of the windings to the supply terminals oriented to the opposite end of the respective windings.

Abstract: A programmable logic controller includes a plurality of input interfaces and a plurality of output interfaces for connection to industrial equipment such as automatic assembly equipment, textile machinery, materials handling equipment, and chemical processes. The input and output circuits can be randomly addressed as to their state through an eight bit bus, which connects in parallel with up to 16 groups of eight input and/output circuits. The controller includes groups of timers which are each manually adjustable as to the timing operation and which are sequentially addressed each time a timing function is called for by the program. The timers are designed to be cascaded in groups to virtually any number of timers. The controller includes a scratch pad memory, half of which retains memory upon power failure and half of which does not. The control of the controller by the operator is made more nearly foolproof by interlocking the operations of control switches.

Abstract: Apparatus and method are disclosed for inspecting a row of hollow pin receptacles in a housing to determine whether or not pins have been properly mounted in the receptacles. A collimated inspection light beam is directed toward one surface of the housing as it passes through an inspection position, so that the inspection beam successively impinges on the receptacles. A photodetector is disposed to face the opposing surface of the housing to receive light, if any, which has passed through the receptacles. Means responsive to the photodetector are provided for generating an output signal indicative of whether or not the pin has been properly mounted in the receptacle. The output signal generating means preferably comprises a threshold detector for detecting when the output of the photodetector exceeds a predetermined threshold.

Abstract: The present invention comprises computer system equipment useful for detection of faults in data transmission within a computer system. Fault detection is accomplished by monitoring the current flow through a digital signal source means, which is characterized in that it only draws significant current during a non-transition period when a fault condition occurs.

Abstract: The disclosure is directed to an apparatus for inspecting the surface of an object at an inspection position. In accordance with an embodiment of the invention, source means are provided for generating a relatively narrow collimated beam of radiation, the source preferably, but not necessarily, being a laser. A scanning means, spaced from the inspection position, is provided for effecting a substantially circularly shaped scan of the laser beam at the inspection position. The scanning means may typically comprise a tilted rotatable mirror which is rotated at the scan rate. A reflector means is disposed between the scanning means and the inspection position. The reflector means, typcially a mirror, has an aperture therein to allow passage of the scanning beam travelling toward the inspection position. The mirror reflective surface is oriented angularly with respect to the axis of the scan so that radiation received from the object is reflected toward an off-axis region.

Abstract: An electrical load in series with a source of AC power is connected across the anodes of a triac with the secondary of a transformer being connected between the triac gate and one of the triac anodes. An electronic switch controls current flow in the primary of the transformer such that a negative voltage is supplied at the gate of the triac during conduction by the primary until saturation of the transformer occurs. After saturation, the electronic switch opens the transformer primary initiating a flyback period during which the triac gate potential rings positive and a consistent peak positive current is supplied to the triac gate from the secondary of the transformer. A half-wave rectifier circuit and transistor may be substituted for the triac for DC load control, or a pair of these transistor circuits may be connected in series to provide AC load control.

Abstract: The present invention is directed to an apparatus for automatically examining hardware items progressing along a track to detect their characteristics and automatically sort the items in accordance with their characteristics. In accordance with one embodiment of the invention there is provided a nut inspection apparatus for monitoring the height of nuts, the apparatus being adaptable to also determine if threading is present on the inner surface of the nuts. In this embodiment there is provided a ramp for carrying the nuts, the ramp having a slot which defines an inspection position. A laser beam is split into first and second beams and adjustable means are provided for directing the first beam transverse the ramp and over the slot at the inspection position, the means being adjustable to a predetermined position above the ramp. A first photodetector is provided for receiving the first beam in the absence of a nut of prescribed height at the inspection position.