Patent application number | Description | Published |
20080223026 | HYDRAULIC POWER MANAGEMENT SYSTEM - A machine having a hydraulic power management system. The machine includes an internal combustion engine driving first and second fixed displacement pumps to produce a combined flow of pressurized fluid. Main and auxiliary implements are operable in response to a flow of pressurized fluid, and a control valve selectively directs the combined flow to the main and auxiliary implements. A power management system is operable to stop the flow of pressurized fluid to the main implement from the second pump when the pressure of the combined flow exceeds a pressure indicative of the impending engine stall. A means for providing the combined flow to the auxiliary implement without regard to the pressure of the combined flow is also provided, and may take the form of a power management override or bypass mechanism. | 09-18-2008 |
20080236153 | Method for operating a multiple speed hydraulic motor - A method of operating a hydraulic motor. In one embodiment, the method includes measuring a temperature of hydraulic fluid associated with the hydraulic motor and comparing the measured temperature of the hydraulic fluid to a first temperature threshold. The method also includes controlling an operational state of one or more hydraulic motor functions based at least partially on the comparison of the measured temperature of the hydraulic fluid and the first temperature threshold. | 10-02-2008 |
20090191068 | VARIABLE VOLUME RESERVOIR - A reservoir for a hydraulic pump system includes a reservoir body, an inner wall dividing an interior of the reservoir body into a first pressure chamber and a second pressure chamber, and a one-way valve connecting the first pressure chamber and the second pressure chamber. A piston assembly forms a first cylinder portion connected to the first pressure chamber and a second cylinder portion that is vented. The piston is movable within the cylinder under the influence of a biasing member to increase and decrease the overall volume of the first pressure chamber. The piston pressures a piston pump inlet connected to the first pressure chamber and maintains a constant pressure within the first pressure chamber under a variety of piston pump operating conditions. | 07-30-2009 |
20100101223 | FLOW COMPENSATED RESTRICTIVE ORIFICE FOR OVERRUNNING LOAD PROTECTION - A hydraulic circuit for an actuator that has a piston and piston rod that will move a load in a first direction, and which can be externally loaded in an opposite direction, includes a flow compensated valve between the actuator and a control valve. When the piston in the actuator is moved in the second opposite direction under the external load and the rate of flow of fluid out of the actuator through the flow compensated valve exceeds a selected rate, an orifice is introduced in the flow path to restrict flow from the actuator. | 04-29-2010 |
20130318958 | CONTROL VALVE ASSEMBLY - A power machine and a power conversion system for a power machine are disclosed. In an exemplary embodiment, the power conversion system includes a pump configured to provide a source of pressurized hydraulic fluid and a control valve assembly to receive the hydraulic fluid. The control valve assembly includes a first valve element configured to direct hydraulic fluid to an actuator when the first valve element is in first and second actuated positions. The control valve assembly also includes a second valve element downstream of the first spool. The first valve element is moveable between an unactuated position and the first and second actuated positions and is configured to direct hydraulic fluid received from the actuator through the second actuated position to the second valve element and to direct hydraulic fluid received from the actuator through the first actuated position to bypass the second valve element. | 12-05-2013 |