Abstract: A motor driving apparatus for driving a motor with a constant voltage by a driving pulse having a predetermined pulse width when the motor is rotated at a high speed, and for chop-driving the motor by using a chopping clock when the motor is rotated at a low speed.

Abstract: A sewing machine speed control device comprising: memory means for storing speed data representing the sewing speeds suitable for various types of sewing machines, sewing-machine-type selecting means for selecting a desired one of the various types of sewing machines and providing a sewing-machine-type selection signal for the selected type of sewing machine, data selecting means for reading the speed data of the selected type of sewing machine from the memory means in response to the sewing-machine-type selection signal, and speed control means for controlling the sewing speed of the selected sewing machine according to the speed data outputted by the data selecting means.

Abstract: Differential wheel slip control is desirable in a locomotive having wheels driven by a plurality traction motors which receive power from an engine driven generator. Wheel slip control in known systems involves increased cost and complexity resulting from sensors required to determine an actual locomotive or individual traction motor speeds. In the subject invention a microprocessor under software control is used to detect and control differential wheel slip. A difference signal is generated in response to a difference between the highest and lowest individual traction motor currents. A first-order-lag of the actual locomotive speed is calculated and compared to the difference signal. If the compared signals differ by more than a preselected reference, a differential slip condition exists and the generator power is reduced by a preselected magnitude. Generator power is continually reduced until the slip condition no longer detected.

Abstract: An apparatus for selectively controlling a plurality of electric motors for driving individual work objects, the apparatus including an electrical switch which is adapted to produce predetermined speed signals for the electric motor selected, a programmable controller disposed in signal receiving relation relative to the electrical switch and which is adapted to generate a predetermined signalling sequence in response to the signal received from the electrical switch, a variable speed motor drive electrically coupled with the programmable controller, and with the electric motor selected, the variable speed motor drive selectively driving the selected electric motor at a predetermined speed in response to the signalling sequence received from the programmable controller, and a sensor adapted to indicate the work performed by the electric motor whereby the electric switch may be selectively adjusted to control the operation of the electric motor selected.

Abstract: A mold clamping apparatus having a plurality of servomotors for drivingly rotating a ball screw as a spindle. A driven timing gear pulley is mounted on a ball nut threadedly engaged with the ball screw whereby the pulley is rotatable integrally with the nut, and driving timing gear pulleys are fixed to output shafts of the respective motors. A timing belt is wound between the driven and driving pulleys. The servomotors are driven so as to produce the same torque by means of driving circuits which respond to the same torque command generated in accordance with a signal representative of a rotational position of one of the servomotors.

Abstract: In a magnet wire fabrication process in which the drawing of wire is "in-line" with the enameling process, it is often a requirement that the drawing machines be supplied with electrical power from the utility grid rather than relying on an "in-house," closely regulated supply of electrical power. In such cases, during voltage dips on the grid, the drawing machine motors will slow down while the wires continue to be pulled from the drawing machine at the same speed as before. A wire accumulator is interposed between the drawing machines and the enameling oven to prevent breakage of wire by providing an accumulation of wire to be used in the event of such a voltage dip. The present invention discloses an apparatus for controlling the various channels of the accumulator so as to provide roughly equivalent amounts of wire in each channel so that the integrity of all channels during a power dip is assured. A central operator control station for effecting the desired control is disclosed.

Abstract: The present invention provides method and apparatus to control a plurality of DC motors each having an encoder by a sole microcomputer. The actual rotating speed of each DC motor is detected in response to the signal from the encoder. A pulse width of a voltage which is applied to each motor is controlled due to the deviation between the actual speed and a preset speed. The output signals from the encoders regarding a specific DC motor to the other DC motor are sequentially selected by a selection signal, thereby controlling the speed measurements and calculations regarding a plurality of DC motors and the duties of electric powers which are applied to the DC motors.

Abstract: An electronic boat controller which can be plugged in and removed from a boat which is hard wired to a plurality of locations which when plugged into allows the boat controller to become electrically wired to power controllers which supply power on a pulse basis to electric motors from a common power supply. This power supply is an electric battery mounted at the rear of the boat. The controller controls two channels which control ultimately two power supplies to two separate and distinct electric motors which are spacially separated at the rear of the motor permitting turning as well as forward control of the boat.

Abstract: In a ring spinning or other textile machine with a multiplicity of thread-winding stations each including one or more variable-speed motors, a central controller supplies periodic or continuous timing signals to respective speed setters of all stations for a predetermined progressive speed change of the associated variable-speed motors. In a specific embodiment, the timing signals are recurrent pulses for the advance of identical programs of the local speed setters whereby the several stations will follow the same routine but with possible relative staggering in time, taking individual delays due to thread breaks or the like into account.

Abstract: In the inching of a grinding mill or similar apparatus which is driven by a pair of synchronous motors through fluid actuated clutches, the motors must be angularly alined one with the other in order that the load be shared equally between the motors. The apparatus of the invention connects the field supply to both motor fields and then it connects a zero frequency supply (i.e. a DC supply) to the stator windings of both motors and ramps up or increases the amplitude of the supply. This brings the rotors into alinement without undue oscillation. When the amplitude of the low frequency supply reaches a predetermined level, the clutches are closed or locked and the motors are connected to the load with the rotors in angular coincidence or alinement.

Abstract: A direct current electric motor marine propulsion system is provided with a pair of shunt wound direct current electric motors which are alternatively connected in a series/parallel circuit configuration. A forward biased diode between the motors in the series circuit, provides for smooth switching characteristics. Fine control of low speed operation is accomplished through the use of a chopper in series with the power source. A contactor connected across the diode provides for reverse current flow during regenerative braking.

Abstract: In a speed control method for digitally controlling the speeds of motors in a sectional drive system including the steps of setting a speed difference of each section with respect to a line speed reference, the speed difference set value is varied by pressing a push button switch and varying the speed difference set value by a unit value every unit operation time when the button switch is pressed.

Abstract: A frequency control utilizing a reference oscillator and a signal controlled oscillator is disclosed. The frequency control maintains the frequency of an output signal at the same frequency as the reference oscillator if there is no signal present at a frequency control input. A signal at the frequency control input causes the frequency of the output signal to be varied accordingly. The frequency control contains a feedback loop which compares the output of the signal controlled oscillator with the fixed frequency of the output of the reference frequency oscillator. The frequency control of the present invention has particular applicability as a frequency control for parallel-connected AC systems.

Abstract: A cable extending onto a drum-cutter loader mining machine has divided branch cable sections to supply electrical current to the individual drive motors for each of two cutting drums. A branch switch coupled in each divided branch cable section and a thyristor controller is coupled in one branch cable section before the switch therein. Crossover lines bridge the branch switches in each divided branch cable section. Bridge switches in each of the bridging crossover lines are used together with the branch switches to deliver electrical current from the controller to either or, if desired, both of the separate drive motors.

Abstract: Apparatus is disclosed for controlling the current flow through first and second loads, such as motors, to thereby control the direction and speed of the motors. The apparatus comprises a first power amplifier connected to the first motor and including an oscillator for generating an oscillator signal having a predetermined frequency of oscillation and circuitry responsive to the oscillator signal for developing a first control current through the first motor. A second power amplifier is connected to the second motor and includes circuitry responsive to the same oscillator signal for developing a second control current through the second motor. The oscillator signal is coupled from the oscillator of the first power amplifier to the circuitry of the second power amplifier, whereby the second power amplifier is slaved to the first power amplifier.

Abstract: A turntable drive motor comprises a stator having a core defining an airgap for receiving a rotor, and a field winding for establishing an alternating magnetic flux of a given frequency therein. An elastic belt is disposed about a pully mounted on the rotor shaft and a flange secured to the turntable. A ring having a plurality of permanently magnetized poles of alternate polarity along its periphery is attached to the flange. A pair of elements are secured to the core for diverting a portion of the stator magnetic flux to a region adjacent to the ringed magnets. The relationship between the excitation frequency and the number of the permanently magnetized poles is such that deviations in the rate of rotation of the turntable for a desired rotational rate are opposed.

Abstract: The invention relates generally to a method of regulating the onboard voltage of a spacecraft and of steering the same by at least two contrarotating motor-generator dynamoelectrical machines.According to said method, there are provided two phases:The energy storage mode, during which each machine receives electrical energy from solar generators through a velocity controlling generator commanded from a synthesis of the data relating to position and rotor velocity;The energy restitution mode, during which each generator supplies energy to a load consisting of the onboard equipment of the satellite. Output monitoring systems effect a synthesis of the data relating to position rotor velocity and additionally control the power switches.