Abstract: A D.C. motor control circuit including a wheatstone bridge type speed regulating circuit with a transistor arranged for detection of the counter-EMF developed across the motor armature to control operation of a drive control circuit. In one embodiment of the invention, an actuating circuit comprises a constant voltage source formed from a constant current circuit connected parallel to an electrical power supply source for the motor and a variable resistor connected in series to the constant current voltage source. A diode applies the output of the variable resistor to the base of the transistor to thereby effect conduction of this transistor.

Abstract: A control system for powering the direct current drive motor of an electric vehicle from a storage battery employs a semi-conductor switch to connect the battery to the motor. Speed control of the vehicle is achieved through operator control of an accelerator which provides an analog output voltage. A multi-vibrator provides a bi-valued output signal varying between 100% on time and 100% off time as a function of the accelerator output. The motor energizing switch is conditioned by this output and by the output of a circuit which compares the motor armature current to a reference value. The circuit includes protection elements so that the switch is opened when the armature current exceeds a preset maximum and is allowed to close again if the multivibrator is still in an "on" mode when the armature current decays below a lower preset value.

Abstract: A three phase motor acceleration control fires SCR's to supply successively longer current pulses to the motor. The SCR's are controlled by comparing a chopped reference ramp and individual trigger ramps.

Abstract: A power generation system for the generation of electrica power from wave motions of the sea comprising a spine on which a plurality of ducks are rockably mounted and for each duck a power generation assembly comprising a hydrostatic transmission having a pump operatively connected with a drive which is rotated back and forth by the rocking motion of the duck, caused by the wave motions of the sea and a variable displacement motor hydraulically coupled to the pump so as to be driven by the pump. The system further includes an electric generator operatively connected to the motor to be driven thereby so as to provide electrical power and a sensing means for sensing the force or velocity condition of the duck and for varying the motor displacement in accordance with such condition.

Abstract: A direct current electric motor including a stator assembly having a stator core of magnetic material. The core has therethrough a generally cylindrical cavity and rotatably mounted therein is a cylindrical rotor assembly. Recesses are formed in the wall of the cavity, the recesses defining therebetween motor poles. Coil bobbins are provided, the bobbins being dimensioned to be slidably received in the recesses in positions bounding respective ones of the poles and each bobbin having wound thereon a selected plurality of turns of magnet wire. The length of the stator core and rotor assembly and the number of turns can be selectively varied to provide a motor of desired torque. The bobbins may be molded and provided with integrally formed end portions which close the recesses in the wall of the cavity and provide a cavity having a smooth and continuous cylindrical surface.

Abstract: A drive system for tape transducer capstan drive control for synchronously controlling capstan drive over a wide speed range, the system being a phase locked loop which encompasses the motor, all drive components, and the capstan. The capstan drive to a tape record receives rotation from a capstan drive motor which also provides a rotational sense output. A control circuit receives the sense output as well as a selected reference frequency signal and processes the signals in accordance with selected binary control input thereby to generate the requisite drive voltage for energization of the capstan drive motor.

Abstract: A speed control system is disclosed for a direct current motor drive energized by a thyristor armature supply. Voltage regulation for the thyristor supply is through a parallel current controller in which an armature current controller is arranged in parallel with positive and negative rate current controllers, the output of this parallel combination being applied as a voltage control signal to the thyristor supply through a parallel switch which mandates priority of control. Normally, the current controller will determine the thyristor armature supply voltage, but if the armature current rate exceeds a preset current rate reference, the parallel switch intercedes and the appropriate rate current controller takes over control of the thyristor supply voltage. When the thyristor armature supply current rate goes below the rate reference setting, the armature current controller will again resume control of the thyristor supply voltage.

Abstract: A protective means for a feeder of machinery having means for transmitting control signal formed from the differential between a predetermined revolution speed and an actual revolution speed of a DC-motor for driving the feeder, and a means to control current in the DC-motor according to said control signal, thereby protecting the motor against excessive current.

Abstract: An improved fluid driven turbine blade system is provided, which is self-governing at relatively high fluid velocities. This is achieved by a combination of two sets of turbine blades, one having a positive efficiency, and the other having a negative efficiency at the fluid velocity at which the self-governing effect occurs. Also provided is a variable friction drive apparatus for powering an energy conversion device. The combination of the improved turbine blade system and the variable friction drive comprises a windmill for driving an electric generator, the windmill having a low required start-up torque at low wind speeds and being self-governing so as not to overspeed the generator at high speeds.

Abstract: A motor speed control system detects a rotation speed of a motor, compares a detected output signal with a reference voltage or a reference frequency to produce an error signal, produces a saw-tooth wave signal of an appropriate repetition frequency, compares the error signal with the saw-tooth wave signal to produce a switching signal, and drives a motor by the switching signal to control the speed of the motor. The system includes a first driver circuit for driving the motor by the output signal of a first comparator circuit which produces the error signal, and a second driver circuit for driving the motor by the output signal of a second comparator circuit which produces the switching signal. The motor is normally driven by the second driver circuit for speed control and is driven by the first driver circuit when the motor is started or overloaded or when the second driver circuit is defective.

Abstract: A brake circuit for a universal motor having an armature and a field winding normally connected in series therewith, the circuit including switch means operable to disconnect the power source and electrically connect the armature in series with the field winding and a brake resistor, with voltage limiting means in parallel with the field winding. The voltage limiting means include biasing diodes for maintaining the voltage across the field generally constant, resulting in a more even deceleration rate and a lower total brake time.

Abstract: Herein described is an electronic control system for guiding a search unit of a nondestructive material tester over sloped or curved surfaces and shapes. More particularly described is the index system used on an indexing-scanning (inspection) device. An oscillator provides a preset number of pulses through an angle rate generator and direction logic to a binary coded decimal pulse counter. The counter keeps track of the input pulses provided thereto (each pulse represents an 0.1.degree. increment) therefore, its contents are indicative of the angle accumulated therein. A pair of read only memories provides the sine function and cosine function of the accumulated angle as a binary coded decimal trigonometric representation of the input angular degree. The signals therefrom control respective Y and Z rate generators whose input clock rate is indicative of the velocity along the curve of the pivot point of the search unit.

Abstract: An improved arrangement for testing the operability of drop wire circuitry associated with yarn handling equipment which does not require yarn movement to be interrupted during tests. A two-position switch operable between normal and test mode positions is included in the circuitry. A jack arrangement is rendered operable with the switch in the test position, thereby permitting an indicator to be selectively inserted in the drop wire circuitry path. The electrical characteristics of the indicator are such as to permit the indicator to be actuated when a drop wire falls while simultaneously disabling the normal response of the remaining drop wire circuitry. Means are provided to selectively bypass the indicator with the switch in the test position to thereby allow the drop wire circuitry to operate as if the switch were in the normal position.

Abstract: A power converter control apparatus comprising continuously controlled converter units and on-off controlled converter units for effecting powering control and regenerative braking control of a DC motor, which is arranged to include a unit change circuit for generating unit changing operation signals in response to a command for instructing the number of the converter units to be rendered operative from a master controllerand conduction phase signals from a phase shifter. In accordance with the unit changing operation signals, the conduction phase signals from the phase shifter are applied as a gate signal to the continuously controlled converter units in response to a powering control or a regenerative braking command, while a minimum conduction phase signal is applied as a gate signal to the on-off controlled converter units in response to a powering control command signal and a maximum conduction phase signal including a commutation marginal angle in response to a regenerative braking command signal.

Abstract: A drive system for a utility vehicle, such as a fork-lift truck, comprises a hydrostatic transmission whose pump is driven by an electric shunt-wound motor having a field winding so energized, under the control of a potentiometer responsive to the fluid pressure in the transmission, that the field current varies inversely with transmitted torque over at least a portion of the speed range of the vehicle. The automatic potentiometer control exerted by the fluid pressure may be overridden by a manually operable lever. The same potentiometer can be used to vary the motor speed in response to the output pressure of another pump which is driven by the electric motor and coupled with the fork-lifting mechanism of the vehicle.

Abstract: A motor heat control circuit is provided for heating an electrical motor during the time of motor shutdown, with the circuit functioning to interconnect a winding of the motor with a source of alternating current voltage for substantially an entire half-cycle of the alternating current voltage but only at intervals comprising a selected plurality of cycles of the alternating current voltage. In its preferred form, the motor heat control circuit is adapted to be connected in shunt circuit with a main motor contactor normally interconnecting the motor winding with the source of alternating current voltage, and includes a controllable semi-conductor switch controlled by digital counting logic which is responsive to clock pulses developed from the alternating current voltage.

Abstract: In a nodding duck for extracting power from waves on water, a control system is incorporated for generating a feedback force related to one or more of the parameters of movement, viz. the displacement position, velocity or acceleration of the duck. The relationship between the feedback force and the parameter is chosen to control the response of the duck for example to enhance the coupling between waves and the duck over a broader range of wave frequencies than would be practicable in the absence of the control system.

Abstract: A method and apparatus for generating electricity from a generator driven by the flow of fluid flowing from a fluid producing well. A fluid driven motor is positioned in the pipeline adjacent to or above the well head such that the fluid passes through the motor to turn the motor shaft to drive the generator. By controlling the electrical load connected to the generator, the force required to drive the motor and thereby the pressure reduction across the motor can be controlled. The electricity produced by the generator may be used to heat the fluid in the pipe to prevent freezing of the fluid. The electricity can be utilized to heat the emulsion in an emulsion separator dehydrator for separating gas, water, and oil prior to its introduction into the pipeline. Separate motor may be utilized for gaseous fluid and liquids. Where the well produces both gas and liquid a separator is employed to separate the gas and liquid.

Abstract: An apparatus is provided for discharging from a condensate sump large amounts of condensate as well as high viscous liquid by means of an electrically driven valve which is arranged at the outlet of the condensate sump and which is controlled to open and close in response to the position of a float whose location within the condensate sump is sensed by proximity switch means connected to operate the valve.

Abstract: An electrically powered instrument having a handle which is adapted to be engaged by the hand of a user during the utilization of the instrument can include a switch-type structure which is actuated by the mere engagement of the hand with the handle without any physical or mechanical motion occurring. The switch includes electrodes extending along the handle which are electrically insulated from one another and which are located in such a manner that they are electrically connected through the user's hand when the hand engages the handle. The switch also includes a power source or supply for applying a voltage between the electrodes and a discriminating or detection structure for detecting the change in the electrical resistance between the electrodes occurring either when the handle is engaged by the hand of the user or when the handle is released by the hand of the user.