Abstract: An improved slag sensor taphole nozzle assembly for a metallurgical vessel having electromagnetic coils protectively located in grooves in the nozzle sidewall, with the nozzle sidewall being (1) non-ferromagnetic and (2) having high electrical resistivity.

Abstract: Resolvers are in common use as angular position sensing devices. Such resolvers normally require difficult to generate sine-wave excitation signals, and extensive decoding circuitry for producing an output signal related to angular position. The subject apparatus utilizes a generator to produce a rectangular-wave timing signal. A logic circuit receives the timing signal and responsively produces first and second rectangular-wave excitation signals, which are delivered to respective stator coils of a resolver. A decoding circuit receives one of the excitation signals and the phase encoded signal magnetically induced in the rotor coil of the resolver, and produces an angular position signal having a duty cycle responsive to the phase difference between the received signals.

Abstract: A hybridized solenoid driver circuit includes a first and second current sensing resistor. The first current sensing resistor is disposed within the flyback current path of the windings of an electrically actuated solenoid and provides a signal proportional to the flyback current only. Control of the solenoid current is effected by operation of a power transistor to controllably connect and disconnect the solenoid from the power supply at a preselected duty cycle. Operation of the driver circuit in the energization mode has no effect on the first current sensing resistor. Conversely, the second current sensing resistor is disposed within the energization current path and provides a signal proportional to the energization current only. Operation of the driver circuit in the flyback mode has no effect on the second current sensing resistor.

Abstract: Improved infrared camera system better enables furnace burden surface temperature measurements and temperature profile measurements and displays of such measurements to be made at various stocklines. An infrared data processing system is incorporated with the camera system which provides automatic acquisition, validation and preprocessing of thermal images from an infrared camera, defines and extracts key features of the thermal images, provides automatic classification and storage of thermal images, periodically reports on displays and printer burden temperature information, and provides convenient data retrieval and data archiving capability. The invention may be incorporated in new or existing methods and apparatus.

Abstract: A power supply circuit (20) having an inductive load (12), three power lines (A,B,C) for conducting current of a 3-phase AC source, an SCR network (24) of six SCRs (1-6) for coupling the current of the source between the power lines (A,B,C) and the load (12), a phase sensor (30) for generating a reference signal in response to one reference phase voltage (AB) of the source, and a trigger circuit (35) for triggering "on" the SCRs (1-6) at predetermined phase angles relative to the voltage (AB). The power supply circuit (20) overcomes constraints such as load inductance which limit the rate of current build-up or decay through the load (12) by gating "on" the SCRs (1-6) at the predetermined phase angles to maximize such current build-up or decay.

Abstract: A circuit (10) and method for converting a circuit input frequency signal (f.sub.i) to a circuit output frequency signal (f.sub.o) comprising a phase-locked loop (22) for multiplying the input frequency signal (f.sub.i) by a value M to produce a multiple frequency signal (f.sub.i M), and a presettable divider for dividing the frequency signal (f.sub.i M) by a settable value N to produce the output frequency signal (f.sub.o). The circuit (10) and method are used to determine engine speed by converting the signal (f.sub.i) to the signal (f.sub.o) which can be used with a counter having a one second time base to determine such speed. The conversion occurs in the frequency domain and follows smoothly any change in engine speed.

Abstract: A frequency/speed controller is provided for controlling the frequency or speed of a device by comparing the frequency of the device to a known reference frequency and matching the device frequency with the reference frequency. The controller uses an up/down counter whose count at any given time is the digital quantized form of ##EQU1## where f.sub.1 and f.sub.2 are the frequencies to be matched.

Abstract: Apparatus (11) for moving a member in accordance with a predetermined speed curve (1) having a plurality of sequential intervals (0-0', 1-2, 2-3, 3-4, 4-5, 5-6, 6-7, 7-8), including controlled devices (12, 14, 16, 18, 30, 34, 40, 44) for controlling the speed of the member and an automatic controller (10) to control the controlled devices to run the member as specified by the speed curve. Prior systems required a highly skilled operator to manipulate various controls to actuate the controlled devices (12, 14, 16, 18, 30, 34, 40, 44), but this has been eliminated through the use of the automatic controller (10). The apparatus (11) can principally be used to control the speed of an engine through a sequence of intervals to test, for example, for smoke emissions during certain of the intervals.