Abstract: This invention is a hydraulic work machine having an electric assist motor coupled to an engine and a hydraulic pump, in the hydraulic work machine of which, a rotational speed and torque of the engine are controlled so that an operating point of the engine moves along a predetermined route for yielding a combustion state of the engine under a transient state that the engine changes in speed and torque. A target speed and torque of the engine 7 are set so that the rotational speed and torque of the engine 7 will change along a predetermined route F in a running region of the engine, respective rates of change of the target rotational speed and torque of the engine 7 are limited, and the engine 7 is controlled to yield the target engine speed. In addition, torque of the assist motor 10 is controlled to yield the target torque of the engine.

Abstract: To provide an engine lug-down suppressing device for hydraulic work machinery, capable of suppressing deterioration in operability of a hydraulic actuator when the hydraulic actuator is caused to operate quickly from a stopped state. Pilot pressure to a tilting control unit of a variable displacement hydraulic pump is controlled by a solenoid valve. A controller controls the solenoid valve in accordance with a target rotational speed signal from an input unit. This control differs according to whether or not a detector detects the pilot pressure created by an operating lever device. In an entire range of the target engine rotational speed, pump absorption torque at the time when the pilot pressure is not detected, falls within a range equal to or smaller than pump absorption torque at the time when the pilot pressure is detected, and is set to approach the pump absorption torque at the time when the pilot pressure is detected with an increase in the target engine rotational speed.

Abstract: To provide an engine lug-down suppressing device for hydraulic work machinery, capable of suppressing deterioration in operability of a hydraulic actuator when the hydraulic actuator is caused to operate quickly from a stopped state. Pilot pressure to a tilting control unit of a variable displacement hydraulic pump is controlled by a solenoid valve. A controller controls the solenoid valve in accordance with a target rotational speed signal from an input unit. This control differs according to whether or not a detector detects the pilot pressure created by an operating lever device. In an entire range of the target engine rotational speed, pump absorption torque at the time when the pilot pressure is not detected, falls within a range equal to or smaller than pump absorption torque at the time when the pilot pressure is detected, and is set to approach the pump absorption torque at the time when the pilot pressure is detected with an increase in the target engine rotational speed.

Abstract: A hydraulic drive system includes a pair of hydraulic drive motors connected in series. Each motor includes a hydraulic circuit with a spring-biased directional control valve and a pair of check valves. The circuits are located in the end cover for each motor, and are in fluid communication with the respective motor and with each other. The circuits are responsive to the pressure differential across the motors, due to the load and direction of the vehicle, and direct flow to one wheel or the other. Flow is directed to the inside motor when accelerating and/or climbing, while the outside motor is allowed to turn freely to compensate for the different turning radius. This reverses when the vehicle is going downhill and/or decelerating, when the motors are braking. If the drive wheel loses traction, the flow and pressure shifts to the other wheel (or to both wheels), until traction is regained.

Abstract: A method and apparatus that converts time-resolved sensor signals into frequency domain signals using Fast Fourier Transforms and power spectral densities. A signal, as a means to assess catalyst performance such as a signal based on sensing oxygen concentration in motor vehicle exhaust in accordance with the present invention is in the time domain and has multiple components at different frequencies. The use of Fast Fourier Transforms isolates the various spectral density which arise from different frequency components of the complex time domain signal. The analysis has been found to be substantially independent of operating conditions. The power spectral density has found to be a precise indication of oxygen storage and release of the catalyst and catalyst performance. The catalyst performance can be signaled to the vehicle operator for on board diagnostics (OBD) of the catalyst.

Abstract: A self-contained, hydraulically operated clutch-type coupling, allowing a minimum of two vehicular type internal combustion engines to be mounted in tandem replacing the standard single block, multi cylinder engine. Flexibility is provided to the driver by a computerized control system to select operation of one or more engines to produce minimum to maximum horsepower at the flywheel, necessary to meet specific road and traffic conditions while maintaining a constant engine (RPM) speed. In one embodiment, a single engine is started to minimize undesirable emissions due to the combination of cold start conditions and wall quenching and fuel conservation purposes. Upon attaining engine operating temperature uniformity, the succeeding engine(s) can be started and operated to provide maximum available horsepower/torque to meet road load conditions.

Abstract: In the disclosed internal combustion engine opposing identical pairs of pistons drive back and forth arm ends of a centrally pivoted beam which is symmetrical about its pivot. Torque is extracted from the beam through an eccentric mechanism which is located between the end of one arm and the pivot. The other arm is provided with a symmetrically located second eccentric mechanism symmetrically spaced from the pivot and substantially identical with the first as regards the dynamic balancing, but not connected to the same output shaft as is the first eccenter mechanism. Also disclosed are combinations in which two or more such engines are connected together as units so that one or more of the units may be completely decoupled from the output shaft and thus inactivated. A special controllable coupling connecting the main shafts of such multiple units permits selective disengagement of the units and synchronized reengagement with predetermined relative angular orientation.

Abstract: A drive system for use in a press in which a pneumatic cylinder and hydraulic pressure transformer are coupled together and connected by separate valves to respective gas and hydraulic sources. The valves are controlled by position transducers arranged along the path of movement of the output member of the transformer.

Abstract: An electronic control module comprising an operational amplifier used as a comparator senses the difference between the throttle settings of a master and slave engine as detected by a potentiometer associated with each engine's throttle control apparatus in order to accordingly adjust the control signal of a fluid pressure actuator of the slave engine, which actuator in turn adjusts the slave engine throttle setting until it corresponds to that of the master engine, at which point the slave engine throttle actuator control signal is maintained constant by reason of the operational amplifier sensing such correspondence.

Abstract: A combination automotive power system wherein a compressed-air motor supplements the primary gasoline-fueled internal combustion engine. Employs a common driveshaft and includes an air compressor powered by the primary gasoline engine, and a compressed-air storage tank intermediate of the compressor and the air motor.

Abstract: A hydraulically driving and controlling - unit comprises a power plant which drives a fluid flow producing device for the separate production and supply of pairs of flows of hydraulic fluid under pressure. The unit supplies at least one pair of flows to at least two fluid motors. Rates of flow in flows are proportionate to each other whereby motors of same pair of flow are actuated and maintained to act with to each other proportionate speed of motion. Unit may be transportable and adaptable to machines or vehicles. The drive unit may include a plurality of power plants and fluid flow producing devices. In such multiple unit one way valves are set into fluid lines which may combine partially after those one way valves for directing each one flow from a different power plant to the same motor. Thereby the unit can continue to operate, when one of the plurality of power plants fails.