Abstract: A quench detector for a superconducting coil is provided which utilizes an optical coupling and a rotary encoder. The presence of a resistive voltage in the superconducting coil created by a quench will cause a rotatable readout coil to move. Movement of the readout coil will be detected by light passing through or reflected by an optical encoder, which will interrupt or transmit light passing from one or more light sources towards one or more light sensors. Preferred embodiments utilize optic fibers for the light sources and sensors, which are unaffected by the high magnetic fields or hostile environment of the superconductor coil.

Abstract: The present invention provides a passive superconducting sensor for quench detection in a superconducting coil. The sensor consists of a first circuit electrically connected to two voltage taps of a superconducting coil. The first circuit uses nonsuperconducting components and preferably contains a resistive element. The first circuit is magnetically coupled to a second circuit by a hybrid transformer. The second circuit is superconducting and contains a readout coil and preferably a second hybrid transformer. The second hybrid transformer is magnetically coupled to a sense coil which detects flux changes in the superconducting coil. The readout coil is coupled to a readout device which measures changes in the current through the readout coil. The current in the readout coil can be made a function only of the resistance of the superconducting coil between the voltage turns and thus can be used to detect a quench.

Abstract: The present invention provides a straightforward sensor and method for quench detection in a superconducting coil, magnet or inductor. The superconducting sensor of the present invention consists of a probe having a twisted loop of superconducting wire in a protective sheath which is co-wound with the superconducting coil, and a readout device. A very small amount of energy is applied to the superconducting loop of wire in the probe by the readout device and its resistance is monitored by readout device. When joule heating occurs in the superconducting coil as a result of a portion becoming normal, the heat is transferred to a corresponding portion of the probe causing a portion of the superconducting wires therein to become normal. This causes the resistance in the superconducting wires to change and this change is detected or measured by the readout device which is magnetically coupled to the wires of the probe.

Abstract: An auctioneering circuit is provided which utilizes voltage signals that are representative of current signals passing through secondary windings of current transformers. A voltage signal is provided which is representative of the current passing through two or more current transformers. This voltage signal is passed alternatively through a resistive path or an inverting amplifier. Negative portions of the voltage signal are passed through an inverting amplifier to provide a positive signal to the non-inverting input of an operational amplifier. This non-inverting input of the operational amplifier is also connected through a resistive path to the source of the originating volt signal. The input signals to the operational amplifier represent a full wave rectified signal. Three such circuits are connected together at a common connection point and the common connection point is connected to ground through a load resistor across which the maximum of two or more voltage signals can be measured.

Abstract: An electronic sensing and triggering circuit including an integrated overvoltage protection circuit is used in conjunction with an energy storage capacitor as well as output transistors for providing a vigorous voltage pulse supplied through a current pulse transformer to the gate of an SCR in a brushless excitation circuit discharge circuit branch.

Abstract: Method and apparatus for monitoring the time rate of successive events the rate of occurrence of which can vary over a wide range by: detecting the successive events during a succession of consecutive time intervals of equal duration; producing successive counts each representing the number of events occurring during each interval in which at least one event occurs; producing successive counts each representing the number of intervals between the end of a respective interval in which at least one event occurred and the end of the immediately preceding interval in which at least one event occurred; and storing representations of the successive counts produced.

Abstract: Electrical apparatus is disclosed in which a line voltage supplies current to an electrically operated solenoid through an operable switch interconnected therebetween. A control circuit is coupled to the switch and controls the operation thereof such that the control circuit operates to increase the duration of current flow to the solenoid when the line voltage level decreases. The control circuit includes appropriate circuitry for generating a reference voltage independent of the line voltage level, for generating a control voltage proportional to the line voltage level, and for operating the switch to permit current flow to the solenoid whenever the control voltage exceeds the reference voltage. The control circuit can also include circuitry to increase the duration of current flow to the solenoid upon the occurrence of vibration with the solenoid above a predetermined level, and/or for increasing the duration of current flow upon initial energization of the solenoid.

Abstract: A microprocessor controlled motor starter is utilized in which an operator can preprogram within limits the number of starts which a motor can be subjected to in a programmed period of time to thus prevent destruction of the motor by accumulated overheating. Significantly more heat is generated during a start of a motor than during the run mode. The foregoing is accomplished by utilizing memory locations in which accumulated times from a first start are sequentially stored in order. If the time found in the latest memory location is larger than the predetermined maximum allowable time then the start is allowed to take place. If it is less than that time then the start is prevented from taking place and a readout alerts the operator as to how much time must expire before the next allowable start may take place.

Abstract: A microprocessor controlled motor starter is utilized in which the short term temperature differential between the rotor bars and the rotor end bells is accounted for by the microprocessor-based system as a function of operator programmed stall time and locked rotor current for the particular rotor in question. The latter information is supplied to the operator by the manufacturer of the motor. The foregoing takes into account a slight deviation between the shutdown temperature, which should be predicted as a function of the manufacturer's data, and the actual shutdown temperature as expressed by an exponential. In the event that the short term temperature differential is exceeded, the microprocessor will enter a TRIP routine causing the motor controller to shut the motor down, thus preventing serious damage to the motor.

Abstract: A microprocessor controlled motor starter is utilized in which the sign values of two phases of voltage are sampled and stored prior to actual motor startup to determine if a phase reversal, a phase imbalance, or a phase loss exists. If any of the preceding conditions exist, the motor start operation is aborted. This generally requires sampling the signs of the appropriate voltages three times during each voltage cycle at approximately equal intervals of 120.degree., give or take 10.degree. or so, and then forming a matrix of voltage signs versus sampling intervals. By comparing diagonal measurements of the sign values in the matrix for three diagonals in a direction of advancing time, phase loss or imbalance can be determined. The determining factor is that each diagonal must contain two values which should be equal, that is, both should be digital ones or both should be digital zeros. If such is the case for the three diagonal measurements, then no phase imbalance or loss exists.

Abstract: A microprocessor control motor starter is utilized in which the microprocessor measures the status of AC input signals which are coupled thereto by way of an isolating electro-optical device. The electro-optical device provides a square wave output signal. Thirty-six samples are made to determine if the output signal is at a digital "1" level or a digital "0" level. If more than 18 digital "1's" are found, that is an indication that the device has failed and a trip operation is initiated by the microprocessor. If less than 18 but greater than some arbitrarily chosen small number such as 6 is found, that is an indication that the switch empowering the optoelectrical device is in a closed but valid disposition. If a number less than 6 is found, that is an indication that the switch is in the open disposition. If the device is failed, the microprocessor will trip the motor.

Abstract: A method is provided for testing induction motors, particularly single-phase fractional horsepower motors, which enables routine testing of all motors in production for both starting and running torque and other desired characteristics. The method consists essentially of applying power to the motor for a very short period of time, such as three or four cycles of the supply voltage, then interrupting the power supply and immediately measuring the instantaneous speed by observing the induced voltage from the deenergized motor terminals. The torque then is verified from the change in speed over this short period. Both starting and running torques can be tested very quickly in this manner by means of solid-state control and computing devices, without connecting anything to the motor other than the power leads. Other desired characteristics of the motor can also be readily determined.

Abstract: An automatic punch press and monitoring system. The monitoring system includes a piezoelectric accelerometer mounted within the stationary die shoe of the punch press, and electronic circuitry including a variable gain amplifier, a detector, an integrator, and a comparator. The monitoring system is manually placed in a "LEARN" mode whereupon the signal produced by the accelerometer during normal operation of the punch press is amplified, detected, and integrated over the time period of one stroke to produce a test function. The gain of the amplifier is automatically adjusted during successive normal strokes of the punch press until the test function is equal to an arbitrary set point, thereby establishing a reference function. The monitoring system is then automatically placed in an "AUTO CONTROL" mode whereupon on each succeeding stroke, with the gain of the amplifier fixed, the test function produced is compared with the reference function.

Abstract: An electronic system to monitor the performance of a pneumatic impact forming tool is disclosed. A signal is generated in real time representing the actuating pressure of the pneumatic tool. Electronic functions operate on the real time pressure signal over a predetermined time portion of each work cycle of the pneumatic tool to generate signals representative of the energy and friction developed in the pneumatic tool during the predetermined time portions of one or more work cycles. The electronic system additionally provides a count of the number of work cycles generated by the pneumatic tool during operation thereof.

Abstract: An automatic punch press and monitoring system. The monitoring system includes a piezoelectric accelerometer mounted within the stationary die shoe of the punch press, and electronic circuitry including a variable gain amplifier, a detector, an integrator, and a comparator. The monitoring system is manually placed in a "LEARN" mode whereupon the signal produced by the accelerometer during normal operation of the punch press is amplified, detected, and integrated over the time period of one stroke to produce a test function. The gain of the amplifier is automatically adjusted during successive normal strokes of the punch press until the test function is equal to an arbitrary set point, thereby establishing a reference function. The monitoring system is then automatically placed in an "AUTO CONTROL" mode whereupon on each succeeding stroke, with the gain of the amplifier fixed, the test function produced is compared with the reference function.

Abstract: A circuit breaker including a flux transfer trip mechanism and a solid state passive overcurrent sensing device having a temperature-dependent switching resistor of resistance material such as vanadium dioxide or lanthanum cobalt oxide.