Abstract: An SCR bridge of an elevator speed control apparatus is connected between an induction motor 5 and two (R, S) of the three-phase power supply terminals. Two diagonally opposite legs of the bridge comprise single SCR's 25, 26, and the other two legs each comprise a pair of parallel, reverse polarity SCR's 21, 22; 23, 24. The third power supply terminal is connected directly to the motor through a single switch contact 8. By appropriately controlling the switch contact and the SCR.varies.s in accordance with the difference between the actual and commanded elevator speeds, the bridge can be configured to implement three phase running during acceleration and constant speed modes, single phase running during a transitional slow down mode, and D.C. braking during a deceleration mode.

Abstract: A wheel-slip control system for a multiple truck vehicle having a speed sensor for producing signals representative of the velocity of each of the wheel axle units. A differentiator connected to each of the speed sensors for differentiating the velocity signals to obtain rate signals. A rate determining circuit for determining the most negative-going rate signals of each of the wheel axle units of each truck. A plurality of deceleration threshold and rate direction detectors and data processing logic to initiate a brake force reduction action on the truck experiencing a wheel slip, and a positive logical "OR" gate for sensing a polarity shift in the most negative rate signal to cause the data processing logic to reapply a braking action.

Abstract: An anti-skid regulating system for front-wheel-drive vehicles. The brake circuits are such that the brakes of one front wheel and one rear wheel, especially the rear wheel diagonally opposite that front wheel, are included in one brake circuit. Measurement transducers are assigned only to the front wheels, and the pressure in each brake circuit is regulated in accordance with the wheel behavior of the associated front wheel. In order to prevent an excessive drop in pressure under certain road-surface conditions caused by the tractive engine torque, the braking effect of the engine on the driven wheels is at least reduced, at least temporarily, in the event that the anti-skid regulation comes into effect.

Abstract: The invention provides a turbocharger (20), compressor (170) and turbine (172) rotors mounted on a shaft (160) supported by ball bearing assemblies (162, 164) such that the compressor rotor (172) and turbine rotor (170) are overhung to one side of the bearing assemblies with the turbine rotor separated from the bearing assemblies by the compressor rotor. The turbocharger (20) includes a turbine nozzle area (230) having a plurality of nozzle vanes (234) spaced circumferentially about the turbine rotor and in the nozzle area through which exhaust air from the engine is received into the turbine. A control linkage (228) is positioned intermediate of the compressor rotor and turbine rotor and controls the position of the nozzle vanes to vary the flow of exhaust gases to the tubine rotor. A concentrically positioned cylindrical module (60) is supported within the compressor inlet by struts (62) extending from the inlet wall (64) to the module (60) thereby dividing the inlet into more than one inlet passage.

Abstract: A bi-directional driver system for an electrical load operable in response to two independent logic command signals provides a means for selecting the direction of current flow in the load when driven by the external command. A bridge circuit employs inputs to dual transistor switches operating in the saturated mode in series with the electrical load, cooperating with common emitter transistor linear amplifiers and diodes, and biased by the input logic signal so as to drive the load current in a predetermined direction. The circuit provides protection from undesired power supply current surges when logic command signals are applied to both inputs, and from transients due to failure of a saturated transistor switch at one input to cease conducting before the application of a command signal to the second input. Embodiments for inductive loads and annunciator lamps are described.

Abstract: A solid state circuit for sequencing a valve mechanism from its normal operating position through a sequence of cycles to blow down various different lines of the network to which the valve mechanism is connected. The circuit may be set to initiate its sequence at one of a number of time periods such as once a day or once a week. Once initiated, the circuit operates a motor drive for the valve mechanism continuing for a timed interval followed by a delay or dwell at each blow down position. A signal is provided to indicate that the circuit is about to enter a blow down sequence followed by the sequence itself. Various alarms and safeguards are provided for the sequence.

Abstract: A pair of interval timer units including a lower right timer (LRT) and a lower left timer (LLT) for controlling a pair of D.C. motors (RM, LM) to drive a pair of load devices accurately and consistently a predetermined lowering distance. The load devices are raised together until stopped by limit switches (LS1, LS2) but can be lowered individually under the interval timer (IT) control. Each timer unit (LRT) includes a voltage regulator (ZD1, ZR1) to provide a constant voltage to a ramp voltage generator (RG) and a reference voltage to a voltage inverter (VI). The ramp voltage is applied through a buffer (IC1B) to one input of a comparator (IC1C). The variable supply voltage is also applied to the voltage inverter (VI) that provides a time reference voltage that varies inversely with respect to variation in the supply voltage.

Abstract: A method for driving a stepper motor. The method includes varying the width of the high level drive impulses of a bi-level drive system based on the desired speed to be achieved by the stepper motor. A microprocessor is used to vary the pulse width.

Abstract: A microcomputer-based motor control system provides overload protection by incrementing a register whenever a full power condition exists and decrementing the register when less than a full power condition exists. When the register reaches a predetermined value, this indicates an overload condition.

Abstract: In an improved motor control system for a pulse width modulated synchronous brushless motor, means for adaptively controlling the "torque angle", i.e. the angle between the rotating magnetic field created by the stator windings and the rotor field created by the permanent magnets on the rotor, is provided. The relationship between the two magnetic fields is controlled as a function of load and speed to provide the optimum operating point at all times. Controlling the torque angle effectively varies the back EMF constant K.sub.e (V/RPM), and the torque constant K.sub.+ (torque/ampere) of the motor.

Abstract: An apparatus for decelerating an elevator at a terminating floor having a plurality of terminating detectors successively provided in the vicinity of the terminating floor for generating a terminating deceleration command value gradually decreasing upon operation of the detectors when the cage of the elevator approaches the terminating floor which comprises; a pulse generator for generating pulses corresponding to the moved distance of the cage; memories for storing the distances from the terminating floor to said respective terminating detectors; a counter for setting the distance information of the detectors of said memories upon operation of the detectors and counting the output pulses of said pulse generator, thereby subtracting the pulses from the set value; and a distance-to-speed converter for calculating the terminating deceleration command value corresponding to the output of said counter.

Abstract: At least one caisson which is part or all of a breakwater forms a water chamber therein whose closure is a pendulum having a natural period in rocking or oscillating the same as a period of stationary wave surges caused in the water chamber by rocking movement of the pendulum owing to wave force impinging against the pendulum. At least one double-acting piston and cylinder assembly is connected to the pendulum, so that when a piston of the assembly is reciprocatively moved by the pendulum, pressure difference between cylinder chambers on both sides of the piston of the assembly controls a change-over valve which in turn controls hydraulic pressure discharged from the cylinder chambers to be supplied to a plurality of hydraulic motors respectively having accumulators of a type wherein accumulated pressure and volume of the hydraulic liquid are proportional to each other, whereby driving a common generator alternately by the hydraulic motors.

Abstract: An engine starter protective and control module (PCM) and system having a 1/2 second start speed delay timer (DT) and a 30-second crank timer (CT) that are started when a start switch (SS) is closed to control a logic circuit (L) that operates a coil driver (CD) to energize the engine starter motor (ES). An engine speed signal from an engine-driven alternator (ALT) shaped in a wave shaping circuit (WSC) is detected by a crank frequency sensor (CFS) which by-passes the delay timer (DT) to continue the cranking if the engine attains an initial speed adequate for starting, otherwise, if the battery is too low, the delay timer (DT) terminates cranking. A run frequency sensor (RFS) receives the speed signal and provides a lockout signal to the logic circuit (L) when the engine speed reaches run RPM. A crank timer (CT) started by the start switch (SS) times a 30-second cranking cycle and a 2-minute cool-off lockout interval to prevent overheating of the starter motor (ES).

Abstract: A device for driving a stepping motor for use in a vehicle is disclosed. The device comprises a plurality of phase coils, a switching means connected to the phase coils, a pulse distributor circuit connected to the switching means for generating control signals thereby controlling the ON or OFF state of the switching means, a connection means for connecting the phase coils to a power supply source, and a current sustaining means connected between the connection means and the phase coils in common therewith.

Abstract: Disclosed is a system and method for recovering energy from elevator apparatus and utilizing the recovered energy for useful purposes. This is accomplished by selectively coupling a hydraulic pump to the elevator drive when surplus energy is available thereby to pump and store pressurized fluid in accumulator devices. Such fluid, when above a predetermined pressure, is utilized to deactivate electrically driven units and drive the same by hydraulic motors supplied with fluid from the accumulator devices. Additional energy is recovered from heat present in the hydraulic fluid downstream from the hydraulic pump and utilized beneficially.

Abstract: An apparatus for exciting a step motor such as a step motor employed as a drive source for conveying original documents in a reading device such as a facsimile system. To vary the feed pitch in the auxiliary scanning direction of the original, staircase waveform exciting currents are applied through A-phase and B-phase exciting coils of the step motor. The apparatus of the invention provides for equal step sizes of the two waveforms and waveforms which are precise complements of one another. Currents flowing in the two exciting coils are sensed and voltages representing the sensed currents are divided in ratios determined by division ratio control signals read from a ROM. The divided signals are compared with a reference signal to provide pulse drive signals of constant currents during each step.

Abstract: A driving and braking system having solid state switches for use with an electric motor. A first switch in series with a motor armature carries current from a power supply to the motor during the driving operation. A second switch couples a voltage from the motor armature to the first switch to render the first switch nonconductive and place the motor in a braking mode in response to a braking signal. The first switch provides armature current and couples a voltage from the motor armature to the second switch to render the second switch nonconductive and place the motor in a driving mode in response to a driving signal. The motor can be switched between the braking mode and the driving mode without bringing the motor to a stop.

Abstract: A motor drive circuit includes ROM in which a plurality of driving speed patterns are stored, a RAM for storing step data indicative of the number of driving rotational steps, and a data processing circuit for supplying motor driving data to a motor control unit in accordance with one of the driving speed patterns selected on the basis of the step data in the RAM. A series of step timing data is included in each of the driving speed patterns. The data processing circuit sequentially reads out the series of step timing data related to the selected driving speed pattern from the ROM and supplies the motor driving data to the motor control unit each time the period of time corresponding to this read-out step timing data elapses.

Abstract: A dynamic braking system is provided for electrically driven wheelchairs to slow the wheelchairs to a stop without needing to use a mechanical brake. A primary switch arrangement is provided for connecting resistors across the right and left wheelchair motors automatically when the switch control is in its off position, either because of purposely positioning the control by the patient or as a consequence of power failure. In addition, a secondary switching system is automatically actuated in response to the primary switching system being moved to its off position to cross connect or short circuit the terminals of the right and left motors to each other only after a given period of time to provide a secondary braking action to the motors and bring the wheelchair to a complete rest.

Abstract: Disclosed is a rotation control circuit for positioning a rotating member driven by a motor comprising a power supply and a motor relay which is energized by the power supply. A circuit is provided for intermittently energizing the relay. The circuit may comprise a first switch means connected to the power supply and a second switch means connecting the first switch means to the motor relay. The second switch means is normally closed and a timer is connected to the first switch means which is operable in response to a closing of the first switch means to generate a relay energizing signal after a predetermined time delay. This signal is operable, through an associated relay, to open the second switch means and thereby deenergize the motor relay after the predetermined time delay. The control circuit is also operable to energize the motor relay in the continuous mode. Finally, safety interlocks are provided in the control circuit to minimize any hazards to operating personnel.