摘要:
The invention provides a variable speed hydraulic pump designed to operate at a maximum horsepower throughout its pressure range by adjusting motor speed according to motor load parameters. In particular, the variable speed hydraulic pump includes a hydraulic pump unit coupled to a variable speed electric motor by a drive unit and to a hydraulic fluid tank for pressurizing and pumping hydraulic fluid when operated by the motor. A motor controller is electrically connected to the motor to supply drive signals to the motor based on electrical characteristics of the drive signals which are dependent on the load exerted on the motor. Suction from the load is provided by both the main pump and a bidirectional supercharging pump by reversing the direction of the motor and shifting a 4/3 valve to connect the main pump inlet to the load and its outlet to tank. In addition, the controller reduces the motor speed at the maximum rated pressure to just maintain the pressure, to reduce the amount of fluid pumped through the maximum pressure relief valve.
摘要:
A drive assembly for driving a moveable component of a vehicle in which the component can adopt one or more positions in which the component prevents access to the vehicle or a part of the vehicle. The drive assembly has an actuator which is coupled to the component and provides the force for moving the component, and a control unit for actuating the actuator. In an emergency operating mode, the actuator can move freely in at least one direction, in such a manner that the actuator allows movement of the component caused by an external force being exerted on the component other than by means of the actuator, preferably by hand. The drive assembly is also provided with a theft detection unit for detecting theft or attempted theft of the vehicle or of goods which are present in the vehicle. The theft detection unit is coupled to the control unit. The drive assembly is designed so that if the assembly is in the emergency operating mode and the moveable component is in a position in which the component prevents access to the vehicle or a part of the vehicle, and then the theft detection unit detects theft or attempted theft, the emergency operating mode of the drive assembly is cancelled, and the drive assembly is then moved into a blocking mode, in which free mobility of the actuator is cancelled and the actuator blocks movement of the component caused by an external force being exerted on the component.
摘要:
A hydraulic operating system has a cylinder which is actuated to raise, hold or lower a load against the force of gravity. An electromagnetic 3/2 valve connects a working chamber of the cylinder to a hydraulic reservoir when not energized, and permits flow from a pump to the working chamber when energized. A non-return valve prevents flow from the working chamber to the pump when the valve is energized. A three position switch operates an electric control unit to raise, lower or hold the load in an intermediate position. When holding in an intermediate position, the control unit constantly energizes the valve during a first period, after which the control unit intermittently energizes and deenergizes the valve so as to lower the load in stepwise fashion during a second period.
摘要:
A hydraulic drive cylinder with a cylinder tube, which at its respective ends has a cylinder base and a cylinder head, thus delimiting a cylinder space. A piston can move to and fro in the cylinder space between the cylinder base and the cylinder head, which piston delimits a head-side chamber and a base-side chamber, which chambers are sealed off from one another by the piston. The piston rod has a free end which is delimited by an end face, which end face is situated in the head-side chamber. At the said free end, the piston rod is provided with a first stop. The piston is provided with a projection which extends towards the cylinder head inside the head-side chamber and is provided, at a distance from the piston, with a second stop, in such a manner that the piston rod can move to and fro along an axial travel with respect to the piston, between a retracted position with respect to the piston and an extended position with respect to the piston, in which the first and second stops bear against one another, and in such a manner that when hydraulic pressure is present in the head-side chamber the piston rod adopts the extended position with respect to the piston.
摘要:
Motor vehicle with a foldable roof, which foldable roof comprises a bow assembly with a main bow, a fabric tensioning bow which can be pivoted up and down, for the rear part of the foldable roof, and a buggy-link system with two links. These links at one side are pivotably connected to each other and are also pivotably connected to the fabric tensioning bow and to a fixing point of the bow assembly respectively. The foldable roof also comprises a power drive unit which is connected for drive purposes to the buggy-link system, and can move the buggy-link system between an extended position, in which the links thereof lie essentially in line with each other and thereby force the fabric tensioning bow downwards, and a bent position, in which the links lie at an angle relative to each other. The power drive unit, for example a hydraulic cylinder, is placed in a side wall part of the vehicle. A transmission mechanism is present, which transmission mechanism connects the drive unit for drive purposes to one of the links of the buggy-link system.
摘要:
Convertible top assembly for a vehicle with a passenger compartment, comprising a convertible top which can move between a closed position, in which the convertible top covers the passenger compartment of the vehicle, and an open position, in which the passenger compartment is open, and a hydraulic actuating device for moving one or more components of the convertible top assembly, the actuating device comprising a hydraulic pump with an associated drive motor and a reservoir for hydraulic fluid, as well as one or more hydraulic actuators, the actuators acting on the convertible top assembly and the pump being designed to supply pressurized hydraulic fluid to the actuators. The actuating device comprises control means which are designed to regulate the volumetric output of the pump while the convertible top assembly is being actuated.
摘要:
Hydraulic operating device, in particular for the operation of a selector fork of a gearbox, and gearbox provided with such an operating device. The device comprises a double-acting cylinder, which is coupled to the selector fork, and a reversible pump. The pump is connected to the working chambers of the cylinder by supply lines. A valve is mounted in each of the supply lines which is operated by fluid flow. This valve comprises a body, a bore formed in the body, a piston, which divides the bore into two chambers, a through-channel, formed in the piston and designed as a flow orifice, connecting the two chambers.
摘要:
The invention relates to a hydraulic circuit for the sequential control of two or more hydraulic cylinders and more particularly for opening and closing the folding roof a cabriolet type vehicle, in which the cylinder space under the piston of each piston cylinder device is selectively connectable to a hydraulic pressure source or to a reservoir for hydraulic fluid, and an additional valve device is provided by which the cylinder space above the piston is also connectable to the pressure source for at least some of the piston cylinder devices. The cylinder spaces above the pistons are hydraulically connected and the additional valve device is constituted by a common electrically operated valve for the piston cylinder devices, by which the cylinder spaces above the pistons are jointly connectable to either the pressure source or the reservoir.
摘要:
A method for producing a metal hose coupling which is designed to be mounted permanently on the end of a hose for pressurized hydraulic oil, which hose coupling creates a fluid connection between the hose and an attachment member, the hose coupling having at least one hose nipple which, in the fitted state, projects into the hose and a connecting part, which is designed to form a connection to the attachment member, the hose coupling furthermore comprising, for each hose nipple, a deformable sleeve which, in the fitted state, rests around that part of the hose which has been pushed onto the hose nipple and, with deformation to the sleeve, holds the hose on the hose nipple, an oil passage extending through the connecting part and the at least one hose nipple. The connecting part and the hose nipple are produced as a single-piece body by means of the metal injection moulding process.
摘要:
Hydraulic control unit, in particular for the folding roof of a vehicle, comprising a reservoir for hydraulic fluid, a pump for drawing hydraulic fluid out of the reservoir and provided with a delivery port for delivering compressed hydraulic fluid, and also at least one first hydraulic actuator of the double-acting type with a first and a second variable working chamber, which working chambers are separated by a piston and are provided with a first and a second connection respectively for supplying hydraulic fluid to said working chambers, further comprising a control valve assembly with a first exit port and a second exit port, which are connected respectively to the first and the second connection of the first actuator, for controlling the movements of the first actuator. The control valve assembly comprises one or more operable control valves and is designed for selectively connecting one of the two or both exit ports thereof to the delivery port of the pump or the reservoir. In addition, an AND valve is provided, having a first and a second entry port and an exit port. The entry ports of the AND valve are connected here respectively to the first and the second exit port of the control valve assembly. The exit port of the AND valve forms a third exit port for controlling one or more following actuators of the hydraulic control unit.