Abstract: A microprocessor-based motor control system operates the rapid advance motor on a slide transfer machine to carry out rapid traverse motions in minimal time. A velocity profile is stored during the acceleration portion of the move and this data is employed to determine when deceleration should begin and to control velocity during the deceleration portion of the move. A position feedback circuit having programmable resolution is employed to develop the velocity profile.

Abstract: A programmable controller has eight I/O buses which will support a corresponding number of I/O modules. The I/O capacity of the programmable controller may be increased by replacing four of the I/O modules with an I/O address module and three I/O interface modules that drive I/O expansion buses. Up to eight I/O racks, each containing three I/O modules and one adaptor circuit, can be connected to the I/O expansion buses.

Abstract: The ends of a loop-gap resonator are extended along a closed path to define an enclosed chamber with a gap extending along its length. A lumped circuit resonator is formed and the magnetic field is confined to the chamber. Openings may be formed in the chamber wall to direct magnetic flux through sample materials outside the chamber, and the cross sectional area of the chamber may be altered to control the energy density distribution of the magnetic field.

Abstract: An improved heating unit comprises a combustion chamber which includes a fuel-supporting perforated burning platform located a distance from the bottom of the combustion chamber. A perforated air plenum is disposed within the combustion chamber a short distance from the combustion chamber top wall to overly a portion of the burning platform. A blower forces air upwardly through the perforations in the burning platform to facilitate waste material combustion and the blower also forces air downwardly through the plenum perforations against the burning platform to further oxygenate the flames and thereby achieve nearly complete combustion. The pressure of incoming air into the combustion chamber forces the exhaust gases through the air passageway above the plenum and out through an exhaust pipe. A heat exchanger, taking the form of a water jacket, surrounds the combustion chamber to cool the combustion chamber and to recover the heat radiated upon combustion of the waste combustible material.

Abstract: An inductor having an air gap in its magnetic core is provided with a magnetic shield which surrounds the inductor air gap to not only reverse bias the inductor magnetic circuit so as to increase the amount of current required to achieve inductor saturation but also to return any stray flux radiating from the inductor back into the inductor magnetic circuit to reduce the radiated electromagnetic interference.

Abstract: Linear motors are employed to position fabricating materials in work stations. The fabricating material forms the movable element of the linear motor and the positioning of the fabricating material is precisely controlled by a closed loop positioning control system which drives the stator windings of the linear motor. Two embodiments are disclosed; one for sheet metal and the other for tubular metal.

Abstract: A dc motor drive includes a current limit circuit which produces a current limit signal that inhibits motor current to its commutation limit over a wide speed range. The current limit circuit includes an analog divider circuit which produces an output signal which decreases as an inversed function of motor speed.

Abstract: A microprocessor-based static converter control circuit includes a free-running counter which is synchronized with the powerline phase and frequency using a zero-crossing detector circuit. Firing angle commands are received and converted to a corresponding firing count. The microprocessor outputs a firing code for the thyristor firing pulse circuit when the count of the free running counter reaches the firing count.

Abstract: A disposable bobbin for a cassette cleaner unit includes a filament spool which holds a cleaning filament that is prewetted with a cleaning fluid. The bobbin is packaged in an impermeable pouch which prevents evaporation of the cleaning fluid until its use in a video cassette player. The bobbin may be used in either Beta or VHS cassette cleaner units.

Abstract: The control program for a programmable controller is entered and edited through a program terminal which displays the control program symbolically as a ladder diagram. Comment instructions are entered into the control program and associated comment data is entered and stored. The comment data is subsequently displayed by the program terminal along with the ladder diagram rung containing the comment instruction.

Abstract: A lumped circuit loop-gap resonator is formed by a plurality of openings formed through a block of material. The openings form inductive loop elements and these are interconnected in a variety of possible networks by capacitive gap elements. String, star, ring and lattice networks are described.

Abstract: Programmable controllers are connected in a ring by serial data links. Each controller periodically transmits information packets on the ring which contain its I/O image table data. All controllers on the ring receive such data and store it in their data tables, and such data is thus available for examination by each controller processor during its execution of the user's control program.

Abstract: An improved semiconductor heat sink for securing a semiconductor thereto for dissipating the heat generated by the semiconductor as well as for supporting those circuit board components which extend upwardly from the circuit board adjacent to the heat sink comprises a vertically extending leg fastened at its lower end to a printed circuit board. The leg has at least one mounting surface thereon for receiving a semiconductor in face to face relationship therewith. Extending outwardly from the leg in opposite directions are a pair of fins, each fin being perpendicular to the mounting surface on the leg. Running along the end of each fin is a downwardly extending projection for engaging a complementary groove in a separate one of a pair of circuit board components, such as connector blocks which each extend upwardly from the circuit board adjacent to a separate one of the fins so that the edges serve to impart further rigidity to the connector blocks.

Abstract: A programmable motor protector includes a protect module which connects through one serial link to a programmer module and through a second serial link to an RTD module. The protect module is a microprocessor which is programmed to monitor the values of various motor operating parameters and compare them against alarm limits and trip limits which are entered through the programmer module. In addition to indicating a trip or alarm condition, the system saves in a diagnostic table an image of the motor operating conditions at the moment a trip is detected. This diagnostic table may be examined using the programmer module.

Abstract: A system for simultaneously displaying graphics and alphanumeric data on a raster scan display screen is particularly suited for use with a computerized and numerical control system for controlling machine tools or the like. A first memory stores a multi-bit data word which includes first and second subgroups of data bits respectively corresponding to an alphanumeric character and several modifications of the data to be displayed. The first subgroup of data bits defines a character field on the screen which consists of lines and columns of pixels, and is delivered as an address to a character generator which produces an output representing an alphanumeric character. A second memory stores graphics data in the form of multi-bit words which correspond to groups of pixels on each line of the screen. The alphanumeric and graphics data, as well as the second subgroup of modification bits, are selectively gated to a decoder which outputs signals to a video generator according to a preselected priority scheme.

Abstract: A PWM, controlled current, voltage source inverter controls an induction motor in response to signals from a power factor control circuit. The power factor control circuit receives signals related to motor terminal voltages and multiplexes them to a comparator. The inverter and multiplexer are sequenced each time the comparator input reaches a reference level. The frequency of the inverter is thus self generated. The power factor of the system can be controlled to implement a variety of control strategies.

Abstract: A current sensing circuit includes an impedance network having a capacitor which produces a voltage proportional to the steady-state component of current and an inductance which produces a voltage proportional to the transient component. The capacitor voltage modulates a carrier signal which conveys the steady-state component through an isolation transformer to a demodulator. The transient component is conveyed through a second isolation transformer and is summed with the demodulated steady-state component.

Abstract: A CRT terminal includes a main unit which houses circuitry and the CRT display. An application module which includes a keyboard plugs into the front of the main unit and electrically connects to its circuitry. A flexible membrane keyboard is employed which includes a keyboard overlay that is easily changed to provide keyboard symbols appropriate to a wide variety of different applications. Resilient bumpers extend completely around the main unit to facilitate its use in industrial applications where physical abuse is common.

Abstract: A tag suitable for attachment to an animal includes a programmed microprocessor which monitors the activity of the animal. Activity is measured by counting the closures of a mercury switch, and when the current activity exceeds a reference activity by a preset amount, a light emitting diode is energized. Four light emitting diodes are provided to indicate four separate levels of activity.

Abstract: A programmable controller includes a memory which stores an I/O image table and a data table. An I/O scanner module updates the I/O image table with the status of I/O devices connected to the programmable controller. The processor executes a control program to perform logical and arithmetic operations on the data in the data table. Such operations may be performed on data of different types and any necessary data conversions are performed automatically. Also, such operations may be performed on entire data files without degrading the response time of the programmable controller.