Abstract:
The invention concerns a secondary-control hydraulic drive system for lifts, wherein a hydrostatic unit driven by an electric motor feeds pressure medium into an operating pressure line (8) in which an applied pressure, if possible a constant pressure, is maintained. One or a plurality of hydrostatic lift cage driving motors (1), designed as hydrostatic units with lifting displacement, is/are connected to the operating pressure network. If these driving motors operate as pumps driven from the lift cage, flow medium is drawn out of a low-pressure line (12) and conveyed into the operating pressure network. Since sufficient flow medium for the pumping operation of the driving motors is always available owing to the preloaded pressure in the low-pressure line, the assembly can be set up in the cellar of a building in order to generate and maintain the high operating pressure whilst the driving motors can be installed at a separate location. This would be impossible if the driving motors were connected in the conventional manner to a tank pipe or a reservoir, since in that case no flow medium could be drawn out of a lower lying tank line during a pumping operation.
Abstract:
The invention concerns an adaptation algorithm for a controller which is monitored by a higher-level measuring loop. The control deviation xw.k is filtered through a noise filter in the measured value detection loop, the filtering factor of said noise filter being varied as a function of the control result and noise level of the measured values. The measuring loop contains a signal filter controlled by the quality of the measured values. The measuring clock sequence with which the controller will be initiated is selected as a function of the measured value quality and control result. The adaptation algorithm is provided in particular for digital controllers.
Abstract:
The invention concerns a valve arrangement (1) for supplying, in a manner adapted to the pressure and volume flow, at least one consumer which, via two working connections (A1, B1, A2, B2) of a constantly adjustable directional control valve (4, 6), can be supplied with hydraulic fluid or connected to a tank (T). Associated with the two working connections (A1, B1, A2, B2) of the valve arrangement (1) is a common pressure balance (16, 18) whose piston (66) is guided in an axially displaceable manner in an axial bore (32) in the directional control valve slide (12) such that, when the directional control valve (4, 6) is suitably triggered, one of the two working connections (A1, B1, A2, B2) can be connected alternatively to the pump connection (P). A control pressure (25), which corresponds, for example, to the highest system load pressure, the individual load pressure or a pressure derived therefrom, acts on both end faces of the directional control valve slide (12) and on the spring side of the pressure balance piston (66).
Abstract:
The hose coupling for the disk-shaped housing (1) of a hydraulic component is intended for coupling and uncoupling by means of a lever a connector provided on a hydraulic pipe and a coupling sleeve provided in the disc-shaped component. Said lever can be displaced in a plane parallel to that of the hydraulic component (10). A shaft secured to the lever (62) has a recess (63) in which the guide element and/or the control piston (40) of the coupling sleeve for linking or disconnecting the connector and the sleeve is installed. The lever can be located in a cavity of the housing (1).
Abstract:
Disclosed is a radial piston pump wherein the fluid to be compressed is drawn through the piston, which can be driven by an eccentric shaft. Piston inlet opening axis is displaced in relation to a centre plane of the drive shaft, parallel to the pistonaxis, so that one of the circumferential edges of the eccentric can be used to control the suction opening.
Abstract:
The invention concerns a hydraulic control circuit in which the pressure medium conveyed by a hydraulic pump of variable delivery (10) is fed, in each case via a metering aperture (17, 31), as a priority to a first hydraulic consumer (14) and only secondly to a second hydraulic consumer (15). It is already prior art to provide a priority valve (45) which comprises a first connection (46) connected to a line section (13) upstream of the metering aperture (17) of the priority hydraulic consumer (14) and a second connection (47) which is connected to the load-indicating line and whose valve member (48) can be acted upon in the opening direction of the connection between the first connection (46) and the second connection (47) by the load pressure of the priority hydraulic consumer (14) and an additional force (51). According to the invention, a priority control system is now produced without additional delivery losses and with sufficient amounts of pressure medium being conveyed in that the valve member (48) of the priority valve (45) can be acted upon in the closure direction of the connection between the first connection (46) and the second connection (47) by a pressure prevailing in a line section (13) upstream of the first metering aperture (17).
Abstract:
Disclosed is an electrically operated directional valve, which can be put in a working position through two magnet units, inside which two operative linkages can be connected using either a pump or a tank. Providing a third magnet unit enables the final position of the valve gate to be set.
Abstract:
Offenbart ist eine Ventilanordung zur Ansteuerung eines Verbrauchers (116) und ein Verfahren zur Ansteuerung der Ventilanordnung, bei denen eine Zulauf-Drosseleinrichtung (4) und eine Ablauf-Drosseleinrichtung (6, 8) unabhängig voneinanderan steuerbar sind. Bei einfach wirkenden Verbrauchern wird die Ablauf-Drosseleinrichtung (6) derart angesteuert, dass bei Erreichen des gewünschten Hydrauliköl-Volumenstromes der Öffnungsquerschnitt der Ablaufdrossel (6) maximal ist, so dass die Energieverluste in der Ablaufleitung (120) auf ein Minimum reduziert sind.
Abstract:
To adjust the incline of a ramp and to create a bending-resistant connection for a ramp (3) pivotably connected to a bridge support (1), a differential cylinder (10) is mounted in the area of the pivot point (2). The piston surfaces of the differential cylinder (10) are impinged upon with pressure that is adjusted in accordance with the prevailing load (11). The pressure in the cylinder chamber (10s) on the side of the rod is a measure of the bending moment in the connecting area between the ramp (3) and bridge support (1). A pressure limiting valve (13) serving as safety valve limits the bending moment. The pressure limiting valve (13) is arranged inside a line (12) directly connecting the two cylinder chambers (10s, 10b) to each other. When the pressure limiting valve (13) is actuated, hydraulic fluid is displaced from the cylinder chamber (10s) facing the rod and fed to the cylinder chamber (10b) facing the floor. To the low-pressure side of the pressure limiting valve (13) is connected a volume control container (15) which equalizes the volume between the hydraulic fluid displaced from the cylinder chamber (10s) facing the rod and the hydraulic fluid needed by the cylinder chamber (10b) facing the floor, and which, when the load on the ramp (3) is reduced, absorbs from the cylinder chamber (10b) facing the floor hydraulic fluid not required by the cylinder chamber (10s) facing the rod.
Abstract:
The invention relates to distributing valve for load-independent control of a hydraulic consumer with regard to direction and speed. Similar distributing valves known per se have a control valve (30) which can be axially displaced in a slide bore hole (11) of a valve housing (10). In a neutral position, said control valve (30) blocks off two consumer chambers (13, 15) from a feed chamber (14) and selectably connects one of the two consumer chambers (13, 15) to a feed chamber (14) and the other consumer chamber (15, 13) to a return chamber in two operating positions. In addition, two brake pistons (51, 52) are arranged in two opposite lying receiving areas (33, 34) of the control valve (30). Both pistons can be pressurized in the direction of an enlargement of the opening section of a flow path leading from one consumer chamber (13, 15) to a return chamber (12, 16) via the respective receiving area, said pistons being pressurized in the other consumer chamber (15, 13) in a direction opposite to that of a spring (53) placed in a spring chamber (12). According to the invention, a slide longitudinal bore hole (36) which can be connected to a load indicator channel (22) extends from one pressure chamber (58) on one brake piston (51, 52) to the other pressure chamber (58) on the other brake piston (51, 52), and can be connected, upon displacement of the control valve (30) from the neutral position, to one consumer chamber (13) or another consumer chamber (15) depending on the direction of displacement.