| Class / Patent application number | Description | Number of patent applications / Date published |
|---|
| 060426000 | Speed of, pressure in, or position of one output motor or motor section controls another | 11 |
| 20080245065 | Control System for Hydraulic Construction Machine - A computing section computes a reference revolution-speed decrease modification amount DNLR; and multiplies an engine revolution speed modification gain KNL by a reference revolution-speed decrease modification amount DNL and then DNLR, to thereby compute an engine revolution-speed decrease modification amount DND based on input change of an operation pilot pressure, which is modified in accordance with DNLR. At the time when a lever operation input from an operation command unit is changed from full stroke to half stroke, if a pump delivery pressure is in a pressure range of a pump absorption torque control region Y where the pump delivery pressure is lower than that in a region X, the reference revolution-speed decrease modification amount computing section | 10-09-2008 |
| 20080282691 | Pressure-compensating directional control valve - A pressure-compensating directional control valve, for actuating hydraulic actuators, comprising at least one modular valve body, with one through receptacle for a slidable shuttle, a driving fluid delivery port connected to a pump, a discharge fluid port, a first output opening and a second output opening, connected to the first and second chamber, of a hydraulic actuator, at least one bridge for selective communication, by way of the shuttle, of the delivery port with the first or second chambers of the actuator, for actuation thereof, a unidirectional hydrostat connected to the bridge to draw selectively a pressure signal of the load of the actuator, the signal for adjusting selectively the delivery pressure of the pump so as to keep substantially constant the pressure drop between the delivery port and the actuator in any load condition. | 11-20-2008 |
| 20080307783 | LOAD SENSE BOOST DEVICE - A vehicle is disclosed having a hydraulic system. The hydraulic system includes a pressure regulator that maintains the output pressure from a hydraulic pump above a predetermined minimum pressure. | 12-18-2008 |
| 20090266070 | POST-PRESSURE COMPENSATED HYDRAULIC CONTROL VALVE WITH LOAD SENSE PRESSURE LIMITING - An array of valve sections in a hydraulic system are connected to a supply line, a tank return line, and a load sense line. One valve sections includes a control valve with a metering orifice through which fluid flows from the supply line to a valve outlet. A load sense node is coupled by a load sense orifice to the load sense line. A load sense pressure limiter prevents pressure at the load sense node from exceeding a threshold level. A pressure compensator is connected in a fluid path between the valve outlet and one of the hydraulic actuators. The pressure compensator opens and closes the fluid path in response to pressure at the valve outlet and pressure at the load sense node, thereby governing the maximum amount of pressure that the respective valve section can apply to the hydraulic actuator. | 10-29-2009 |
| 20100024411 | Hydraulic system having automated ride control activation - A hydraulic system for a mobile machine having an implement is disclosed. The hydraulic system may have a hydraulic actuator configured to move the implement, a storage device configured to store pressurized fluid, and a valve operable to fluidly communicate the storage device with the hydraulic actuator. The hydraulic system may also have a sensor associated with the mobile machine to generate a signal indicative of a speed of the mobile machine, and a controller in communication with the valve and the sensor. The controller may be configured to compare the speed of the mobile machine to a setpoint and to determine an amount of time elapsed while the speed of the mobile machine exceeds the setpoint. The controller may further be configured to selectively operate the valve to fluidly communicate the storage device with the actuator based on the elapsed amount of time and the speed to cushion movement of the implement. | 02-04-2010 |
| 20100024412 | Control Apparatus for Working Vehicle - There are provided: a travel circuit HC | 02-04-2010 |
| 20100031649 | Hydraulic Drive Device for Hydraulic Excavator - [Problem] To provide a hydraulic drive system for a hydraulic excavator, which makes it possible to efficiently perform grading work by using residual energy of pressure oil in a hydraulic circuit although no attention has been paid to the residual energy in conventional technologies. | 02-11-2010 |
| 20100212308 | HYDRAULIC CONTROL ARRANGEMENT - The invention relates to a hydraulic control arrangement for a mobile machine tool, particularly for a forklift, comprising at least two hydraulic loads ( | 08-26-2010 |
| 20100218493 | TORQUE CONTROL APPARATUS FOR CONSTRUCTION MACHINE THREE-PUMP SYSTEM - Torque control for a construction machine three-pump system that can accurately control the total absorption torque of first, second, and third hydraulic pumps and effectively use the output torque of an engine. A pump base torque computation section | 09-02-2010 |
| 20110131968 | METHOD FOR CONTROLLING A PUMP AND MOTOR SYSTEM - A method of controlling a pump and motor system having at least one of a variable displacement pump and a variable displacement motor. The method may comprise providing an engine drivingly coupled to a primary load and a secondary load, the secondary load being driven by the pump and motor system. The method may also comprise sensing a change in engine speed in response to a change in the primary load. The method may further comprise changing the engine speed to compensate for the primary load change. The method may further comprise changing a displacement of the at least one variable displacement pump and the variable displacement motor to maintain a constant secondary load. | 06-09-2011 |
| 20150113971 | HYDRAULIC CONTROL SYSTEM - A hydraulic control system includes a first oil passage, a first oil pump, a second oil passage, a second oil pump and a check valve. The first oil pump is disposed in the first oil passage. The second oil passage bypasses the first oil pump, includes an intake oil passage and a discharge oil passage, the intake oil passage and the first oil passage are connected to each other at a connection point, and the discharge oil passage includes an air vent hole. The second oil pump is disposed in the second oil passage, configured to take in oil from the intake passage, and configured to discharge the oil into the discharge oil passage. The check valve is provided between the connection point and the air vent hole, configured to restrict flow of the oil from the air vent hole toward the connection point via the second oil pump. | 04-30-2015 |
