摘要:
A fuel injection control device (an electronic governor (12) and a controller (13)) for an engine (1) is capable of controlling the governor region to an isochronus characteristic. A working machine controller (18) receives a delivery pressure signal (P) and controls a regulator (16) in such a manner that when the delivery pressure of a hydraulic pump exceeds a predetermined pressure (P1), the displacement volume of the hydraulic pump does not exceed a value determined by a preset pump absorption torque curve (20) and when the delivery pressure of the hydraulic pump (2) is not more than a predetermined pressure (P1), the displacement volume of the hydraulic pump increases as the delivery pressure of the hydraulic pump lowers from the predetermined pressure (p1). This makes it possible, even if the governor region is controlled to an isochronus characteristic, to increase the delivery rate of the hydraulic pump as the engine load becomes lighter.
摘要:
Disclosed is a hydraulic fluid pump (80) for a motor vehicle brake system, comprising delivery means (110, 120) for delivering hydraulic fluid against a hydraulic counter-pressure prevailing in one part of the vehicle brake system (140, 150). Said hydraulic fluid pump (80) further comprises means (270), preferably an elastomer component in the motor shaft bearing (200, 220), for modifying the volume delivered by the delivery means (110, 120) in accordance with the level of the hydraulic counter-pressure.
摘要:
The invention relates to an axial piston machine comprising a pivoting cradle having variable tilt. The axial piston machine has at least one adjustment device extending substantially in the longitudinal direction of the axial piston machine. The axial piston machine further comprises a return element for returning to a position of the pivoting cradle. The return element and the adjustment device are disposed in a plane extending parallel to an axis of rotation of the axial piston machine and perpendicular to a pivoting axis of the pivoting cradle.
摘要:
A pump torque control system is capable of preventing from hunting due to interference between speed sensing control and control on an engine speed of a prime mover when the temperature of a hydraulic fluid is low, and performing appropriate pump torque control. A regulator 31 controls displacement volumes of hydraulic pumps 2 and 3 to ensure that the total absorption torque of the hydraulic pumps 2 and 3 does not exceed a set maximum absorption torque. An engine sensor 33, a hydraulic fluid temperature sensor 34, a solenoid proportional valve 35, and a controller 23 perform the speed sensing control to ensure that the maximum absorption torque of the hydraulic pumps 2 and 3 is reduced. The maximum absorption torque is set in the regulator 31 based on a deviation between a target engine speed of the prime mover 1 and an actual engine speed of the prime mover 1. A second modification factor calculating section 45 and a control gain modifying section 49, which are included in the controller 23, change a control gain of the speed sensing control based on a value detected by the hydraulic temperature sensor 34 to ensure that the control gain is reduced as the temperature of the hydraulic fluid is reduced.
摘要:
A hydraulic circuit of construction machinery, wherein, when three hydraulic pumps are used, the displacement volumes of first and second hydraulic pumps are controlled based on the discharge pressures P1 and P2 of the first and second hydraulic pumps and a discharge pressure P3' obtained by reducing the discharge pressure P3 of a third hydraulic pump by a pressure reducing valve (14) and the displacement volume of the third hydraulic pump (3) is controlled only by the discharge pressure of the third hydraulic pump (3) so that one of the three hydraulic pumps is not affected by the variation of torque of the other hydraulic pumps, whereby a stable flow can be assured by preventing the pressure oil discharged from the third hydraulic pump (3) from being affected by the variation of the discharged flow from the first and second hydraulic pumps (1) and (2), i.e., by the variation of a torque consumption.