Abstract: The present teachings relate to a fluid mechanical converter having at least one energy-accumulator mass system that can be powered by a power drive. To provide a fluid mechanical converter, which improves overall efficiency using the simplest components, it is proposed according to the present teachings that the displacement of the driven energy accumulator-mass system is overlaid with a displacement that is caused by at least one inertial force.

Abstract: The invention relates to a fluid mechanical converter having at least one energy-accumulator mass system that can be powered by a power drive. To provide a fluid mechanical converter, which improves overall efficiency using the simplest components, it is proposed according to the invention that the displacement of the driven energy accumulator-mass system is overlaid with a displacement that is caused by at least one inertial force.

Abstract: A hydraulic pump system having a pump for pressurizing fluid and a hydraulic chamber for receiving fluid from the pump. An even flow of fluid is outputted from the chamber to a valve assembly. The chamber is formed from a resonator and a resonator cover that are attached in a fluid tight manner by elastic fasteners. The resonator cover acts as a pressure controller in that when the pressure of fluid is of sufficient magnitude, this force creates a gap for controlling fluid pressure output to the valve assembly.

Abstract: The object of the present invention is to provide a method for limiting the hydraulic maximum pressure of a power-assisted steering system, which permits effective pressure limitation and thus protects the individual elements of the power-assisted steering system, i.e., a pressure limitation not far above the desired maximum operating pressure, but on the other hand does not require an overdimensioning of the individual segments of the power-assisted steering system.

Abstract: To improve a method for controlling the valve characteristic in electrohydraulic power-assisted steering systems of motor vehicles so as to prevent any impairment of the steering precision, the invention proposes to control the speed of the electric motor as a function of the current consumption such that the actual current consumption and the actual speed of the electric motor are continuously measured up to a maximum speed and compared with values for the setpoint speed at the respective value of the current consumption stored in a memory and in case of deviation a correction to the setpoint speed is effected.

Abstract: A apparatus for use with an open center steering valve (3) of a hydraulic power-assisted steering unit of a motor vehicle. The apparatus comprises an electric motor operated pump (5) and a hydraulic accumulator (7) for storing a pressurized quantity of hydraulic fluid. The hydraulic accumulator (7) is hydraulically connected to the pump (5). The pump (5) supplies the pressurized hydraulic fluid to the hydraulic accumulator (7). The apparatus further comprises a valve arrangement (10) for controlling hydraulic fluid flow from the hydraulic accumulator (7). The valve arrangement (10) has a riser (25), a slide valve (19), a valve seat (21), and an electromagnet. The riser (25) is hydraulically connected to the pump (5). The valve seat (21) has an opening which hydraulically connects the riser (25) and the hydraulic accumulator (7).

Abstract: In order to reduce the number of components required and increase the service life by preventing friction resulting from large-diameter seals, a steering valve (1) is provided which has a closed center for supplying hydraulic pressure to an actuator and which comprises an input shaft (2), an output shaft (3), a torsionally resilient element (11) which is connected at one end to the input shaft (2) and at the other end to the output shaft (3), a control pressure switching arrangement (4), and an axial force conversion unit (19-23), wherein at least one hydraulic line (15) guides reaction pressure in the input shaft (2).

Abstract: The invention concerns a steering valve with a closed center for supplying an actuator with hydraulic pressure, the steering valve comprising an input shaft, and output shaft, a torsionally resilient element which is connected at one end to the input shaft and at the other end to the output shaft, a control pressure switching arrangement and a torque/axial force conversion unit. A spring loaded seat valve is located in a bore of the input shaft, and closes a fluid passage passing through the torsion tube. The torque/axial force convertor opens the seat valve when relative twisting of the input shaft with respect to the valve casing occurs. According to the invention, in order to improve the response dynamics of such a steering valve, the valve comprises at least one axial bore for supplying hydraulic pressure. At one end this bore is closed by a valve which is loaded by the torque/axial force conversion unit against the hydraulic pressure.

Abstract: A torsion element (1) for a steering valve is provided. The torsion element (1) comprises a torsionally elastic rod member (2) having axially opposite first and second end areas (3, 4) which are rotatable relative to one another. The rod member (2) has a circumferentially spaced plurality of radially and axially extending indentations (10) adjacent the second end area. A generally tubular, torsionally stiff sleeve member (6) encircles the rod member (2) and is fixedly attached to the first end area (4) of the rod member. The sleeve member (6) includes a circumferentially spaced plurality of radially and axially extending grooves (9) which align with and radially overlie the plurality of indentations (10) in a neutral steering condition. The sleeve member (6) further includes a circumferentially spaced plurality of radial slots (7).

Abstract: In order to improve a method for controlling the speed of an electromotor-driven pump of a hydraulic power steering device of a motor vehicle as a function of the steering speed, so that the overall efficiency of the system is optimized in a simple manner; it is proposed that the required volume flow of hydraulic fluid, calculated according to a determined steering speed, is increased up to a maximum by an additional correction factor that takes into account the overall efficiency of the system, in order to use the result to calculate and to adjust the set speed of the pump.