Abstract:
A flow control system for controlling a variable displacement pump including a metering valve in fluid communication with the pump for metering an output of the pump. A regulating valve receives a portion of the output of the pump as a bypass flow at a first pressure, wherein an output of the regulating valve is at an interim pressure. The interim pressure is substantially equal to an average of the first pressure and a low reference pressure. An actuator sets a displacement of the pump by acting on a piston connected to a cam ring of the pump. The actuator receives the interim pressure and, thereby, the output of the variable displacement pump is determined.
Abstract:
A motor, such as an internal combustion engine or an electric motor, drives two or more pumps, which pump fluid through a discharge system, and a speed measuring device is provided for producing a signal when the speed of the motor is reduced due to the load on the motor reaching a predetermined high value, short of an overload. Two or more pump discharge regulators are provided, one for each pump, cooperating with the measuring device to reduce the output of at least one of the pumps in response to a signal to thereby prevent overloading of the engine or motor.
Abstract:
A radial cylinder hydraulic motor having continuously variable displacement capabilities includes: oscillating hydraulic cylinders which are driven to oscillate through an eccentric crankpin formed on the motor shaft and carrying a radially movable ring adapted to be shifted along the radial direction of the crankpin by actuation of opposed counteracting hydraulic cylinders housed within the crankpin; a hydraulic control circuit for controlling and adjusting the positions of said counteracting hydraulic cylinders in a continuous manner; an electronic control circuit adapted to control the hydraulic control circuit and process signals from at least one position sensor arranged to detect the positions of said oscillating cylinders; a rotary joint for hydraulic conduits through which said counteracting hydraulic cylinders are controlled and adjusted.
Abstract:
A radial cylinder hydraulic motor having continuously variable displacement capabilities comprises: oscillating hydraulic cylinders (1) which are driven to oscillate through an eccentric crankpin (2) formed on the motor shaft (3) and carrying a radially movable ring (14) adapted to be shifted along the radial direction of the crankpin by actuation of opposed counteracting hydraulic cylinders (5, 6, 7) housed within the crankpin; a hydraulic control circuit for controlling and adjusting the positions of said counteracting hydraulic cylinders in a continuous manner; an electronic control circuit adapted to control the hydraulic control circuit and process signals from at least one position sensor arranged to detect the positions of said oscillating cylinders; a rotary joint (8) for hydraulic conduits (9, 10) through which said counteracting hydraulic cylinders are controlled and adjusted; wherein the sensor (45) is an angular position sensor placed close to the oscillation axis (C) of at least one oscillating cylinder (1) to measure, based upon changes in the signal, an angular position currently entered by the cylinder liner during the swing.
Abstract:
Proposed is a hydrostatic radial-piston motor (10) with an adjustable cylinder ring (18) which has integrated means designed to determine the eccentricity (20) between the cylinder ring (18) and the rotor (14). The eccentric position of the cylinder ring (18) leads, in conjunction with the rotating rotor (14) and the restraining of the guide shoes (17) on the cylinder ring (18), to a stroke action of the piston (16) in the radial direction. This, and kinematic conditions in the motor (10), leads to a change in the distance between two consecutive guide shoes (17). This change in distance takes place in proportion to the eccentricity (20) of the cylinder ring (18) and is determined by a measuring device. This measuring device has a signal transducer (27) which generates an amplified voltage signal as the guide shoes, which act as signal generators, move over it. This signal is fed to evaluation electronics (28) where it is used to determine the eccentricity, rotor rpm and other parameters.