Abstract: A proximity switch assembly (10) for signaling the location of a movable member (36) at either of opposite end limits of movement relative to a stationary frame (44, 46) includes a compact elongate housing (58) adapted to be mounted on the frame to extend along the path of movement of a power driven member (32), such as the piston rod of a hydraulic cylinder, which shifts the movable member between its end limits. The proximity switch is fixedly mounted in the housing and carries a switch actuating member (68) mounted for sliding movement over a relatively short distance sufficient to move an actuating target (74) into and out of actuating proximity of an air core proximity sensing coil (120) within the housing. Lost motion abutment shoulders (70, 72) on the switch actuation member and power driven member (54) move into engagement with each other as a power driven member approaches each end of its stroke.

Abstract: An optoelectronic triangulation sensor mounted adjacent a path of travel of a material web or individual paper sheets has a pivotable lever biased toward a fixed reference platen to bias the article(s) against the platen. The sensor light source is focused on a target carried on the back of the lever and reflected to a position-sensitive detector (e.g. lateral-effect photo-diode), the output of which varies in an analog signal in direct proportion to displacement of the lever. A relatively wide included angle between light source and PSD receiver shortens the range of the sensor and eliminates a need for pulse modulated light. The current driving the light source is monitored to emit a signal when the light source current exceeds a threshold, signaling the need for maintenance on the sensor such as cleaning the lens.

Abstract: A displacement gauge or gauge for detecting misalignment (3) employs four magnetic coils (24N, etc.) 90.degree. apart, (each) energized by an oscillator (36N, etc.), to sense the dislocation of a machine part, such as a post (12), near their center. A nominal position of the part (9 or 12) relative to a reference component (6) of the machine is first established. Subsequent displacements are detected and are indicated if they exceed a predetermined threshold magnitude.Signals from the four coils are combined in such a way that the magnitude of the radius of a displacement of the part (9 or 12) from the nominal position is ascertained approximately, irrespective of the direction of displacement from the reference part (6). The combination signal (at 64) is the greatest of (a) the absolute value of a north/south displacement signal, (b) the absolute value of an east/west displacement signal, and (c) 0.

Abstract: A displacement sensor or displacment gauge (3) for detecting misalignment measures the dislocation of a machine part, such as a post (12), by means of four magnetic coils (24N, etc.) deployed 90.degree. apart around the post and each energized by an oscillator (36N, etc.). A reference position of the machine part (12) relative to another component (6) of the machine is first established. Subsequent displacement is detected and excessive displacement is indicated if it exceeds a predetermined threshold magnitude.Signals from the four coils are processed combined in such a way that the magnitude of the radius of a displacement of the machine part (12) from the reference position is ascertained and provided irrespective of the direction of the displacement.

Abstract: A through-beam optical detector system using a universal dual port transmitter housing module is provided with an auxiliary light source in the available but unused port of the transmitter housing module for transmitting visible light to aid alignment of transmitter and receiver.

Abstract: A new and improved method and apparatus is disclosed for detecting a target location with respect to an inductive tank circuit. A sensing field such as an electromagnetic field is established having an amplitude which changes in value due to the presence of a target in the sensing field. A first energy level is provided to maintain the field at an amplitude. A second energy level is provided to achieve a value for the field within the predetermined amount of time after initiation of the field.

Abstract: A universal 3-wire switch module is provided for normally open and/or normally closed load control modes. The universal switch module is field convertible from P type DC to N type DC to P type AC to N type AC configurations as programmed by installation wire connection, without internal changes to the switch module. A single switch module replaces the prior dedicated switch modules used for the various configurations. The switch module is further characterized by its versatile application to a wide range of voltage.

Abstract: A circuit for a switch which receives an input from a sensor head (18) such as a proximity sensor, limit switch, or other type of condition-responsive sensor. In its most complex form the circuit includes a power supply/regulator (24), an output load current source (12), an output load current sink (14), input logic (16) to receive the signal from the sensing head, a selector (10) to determine whether the source and sink will be normally open or normally closed, and a device (26) for checking the outputs for faults and indicating the presence of such. Other circuits include certain combinations of these parts or variations of these parts.

Abstract: An A.C. electric power usage measuring and display system using microcomputer based digital processing. Power usage pulses optically sensed from a watthour meter rotary disc and time pulses sensed from the 60 Hz A.C. power line are input to a microprocessor that is programmed to calculate and display the day of the week 1 to 7, the time of day on a 24-hour clock basis, the total watthours and kilowatthours since the start of a billing period on a decimal basis, the peak interval watthours and kilowatthours on a decimal basis, the peak interval start time and end time on a 24-hour clock basis for a peak interval of predetermined time, the peak power demand in kilowatts on a decimal basis, the day of the peak demand on a weekly 1 to 7 basis, the time of the peak demand on a 24-hour clock basis, and the present demand in kilowatts on a decimal basis.

Abstract: A ground fault interrupter for two and three wire, single phase load circuits employing a circuit breaker having an electro-responsive contact trip-open mechanism, a fault sensing differential transformer, an operational amplifier providing characteristic output pulses whose magnitude depends upon the non-presence or presence of a ground fault and whether the latter is resistive or reactive in kind, and an energizing circuit for the electro-responsive contact trip-open mechanism including a transistor which is normally held non-conducting in the absence of a ground fault and rendered conducting whenever a resistive ground fault occurs. A capacitor in circuit with the amplifier output and transistor base renders the transistor immune from amplifier pulses characteristic of reactive ground faults. Varistors are included between the load circuit wires to suppress transient voltage surges from falsely inducing nuisance ground fault interrupting action.

Abstract: An electronic A.C. switch which affords either "normally open" or "normally closed" type of operation to a connected alternating current source and load in accordance with which of two alternate terminals such source and load are connected in addition to a third common terminal. Its operation is automatically inhibited in the event the A.C. source and load are connected to both of such alternate terminals simultaneously. It can be used with a wide variety of electrical sensor devices for effecting its operation between either of its normal and opposite circuit states.

Abstract: An on-delay timer of the solid state type incorporating integrated circuit (IC) modules including a five-transistor array in a dual-in-line package (DIP), a multiple-transistor monolithic triggering comparator circuit used as a timer, and a bidirectional thyristor or Triac. All voltages are referenced to one power line to afford simplicity of circuitry wherein the load current does not flow through the pilot switch. A leaky switch detector circuit using a simple voltage divider is incorporated in the pilot switch circuit.

Abstract: Ground to neutral fault protection employing dormant oscillators which are only energized and function on the .[.occurance.]. .Iadd.occurrence .Iaddend.of such type of a ground fault. Combined with known types of two and three wire single phase AC ground fault interrupters to provide circuit interruption regardless of which wire is faulted to ground.