摘要:
The invention relates to a control and regulating device for a hydrostatic transmission which comprises a reversible hydraulic pump that can be driven by a driving motor, at least one hydraulic motor that is connected via two working lines to the hydraulic pump, and an adjusting device that can be acted on by an adjusting pressure for adjusting the volume and direction of displacement of the hydraulic pump, together with a displacement-direction control valve for controlling and regulating the action of the adjusting pressure on the adjusting device, can be actuated as desired both by a control signal that is proportional to the speed of rotation of the driving motor and predetermines the direction of displacement of the hydraulic pump and by a working pressure signal that is proportional to the working pressure in the working line then carrying the high pressure. To enable a load that has been decelerated to a standstill both to be maintained at a standstill and also to be shunted without mechanical braking, even when actuation of the displacement-direction control valve by the control signal is interrupted, the invention provides for switching over the working pressure signal applied to the displacement-direction control valve in the absence of the control signal.
摘要:
The invention relates to a hydrostatic drive comprising a hydraulic pump (1) and at least one hydraulic engine (3). Said hydraulic engine (3) is contacted to a closed circuit via a first working line (5) and a second working line (6). In order to limit the swept volume flowing in one of the two working lines (5) towards the hydraulic pump (1), a volume flow divider (60) is provided in the working line (5) and allows to remove a partial volume flow from the working line (5).
摘要:
The invention relates to a hydrostatic transmission having a hydraulic pump (1) and an adjustable hydraulic motor (2) which is connected to first and second working lines (13, 14) of which at least the first (13) leads to the hydraulic pump, and a setting member (40)--for setting the motor displacement volume--is connected with a setting device (4) which upon load operation of the hydrostatic transmission can be acted upon by a setting pressure in a first setting pressure line (44, 57, 43) connected at least to the first working line, and in the case of overrun operation, can be acted upon by the setting pressure in a second setting pressure line (45, 51, 43), connected at least to the second working line. There is a brake valve (6) arranged at least in the second working line downstream of the connection of the second setting pressure line and which upon overrun operation of the hydrostatic transmission the respective working line is restricted. In order to be able to adapt the braking effect to differing operating conditions, there is provided a relief valve device (9, 10) which upon overrun operation is controlled by means of a control pressure taken from the second setting pressure line (45, 51, 43), against a counter-pressure (66, 76) in the direction of throughflow position and in this throughflow position relieves the setting pressure in the second setting pressure line (45, 51, 43) controllably via a relief line (65) to the tank (12).
摘要:
In a summation power output regulating system for first and second hydrostatic machines (3, 4), having a common drive and comprising at least two hydrostatic transmissions (1, 2), each of the machines (3, 4) having a hydraulic control device (7, 8), wherein the second machine (4) is provided with a hydraulic power output regulator (24) which regulates the pressure acting on the control device (8) in dependence on the power output of the second machine at that time and a control pressure, dependant on the working pressure of the first machine, is transmitted by means of a hydraulic actuator to the power output regulator (24), substantially 100% utilization of the power available is attained with a simple construction and function by providing the first machine (3) with a power output measuring valve (34; 63, 64) which determines the power output at the time and regulates the control pressure (P.sub.3) in dependence on the power output of the first machine.
摘要:
A pressure limiting valve comprises a valve closing body (7) which comprises a valve closing surface (8) which together with a first valve seat (9) opposing the valve closing surface (8) forms a first seal seat and a valve closing body orifice (11), which is surrounded by a second valve seat (12) which together with a closing head (14) configured on an axially displaceable valve bolt (13) forms a second seal seat and with a spring plate (15) which is connected to the valve bolt (13) and axially displaceable therewith, and a first return spring (10) clamped between the spring plate (15) and the valve closing body (7), which pretensions the valve bolt (13) against the second valve seat (12) configured on the valve closing body (7) and a second return spring (35) which pretensions a valve unit (7, 13, 15, 10) against the first valve seat (9). In the valve bolt (13) a longitudinal bore (53) is provided extending over the entire axial length of the valve bolt (13).
摘要:
The gear pump unit (100) comprises a pump cover (1), an internal rotor (16) mounted rotatably in a recess (9) of the pump cover (1) and formed in a rotationally fixed manner on a driven plug-in shaft (11), and an external rotor (19), which is rotatably mounted in the recess (9) of the pump cover (1) eccentrically relative to the axis of rotation (A) of the internal rotor (16). The external rotor (19) is in mesh with the internal rotor (16) only in a first angle-of-rotation range (α). In a second angle-of-rotation range (β) lying opposite the first angle-of-rotation range (α), the internal rotor (16) is in contact with an inner surface (25) of a web (23), which is disposed in the recess (9). The outer surface (26) is in contact with the external rotor (19). After closing of the recess (9) by a cover plate (27) fastened to the pump cover (1), an admission pressure chamber (21) and a low-pressure chamber (22) are therefore formed in the recess (9). A holding element (33), which is held in the pump cover (1), in the initial assembled state of the gear pump unit (100) holds the cover plate (27) at a fixed angle of rotation on the pump cover (1).
摘要:
The invention relates to a hydraulic controller, in particular for the control of the rotating mechanism of an excavator. In a hydraulic drive circuit a drive hydraulic pump (2) and a drive hydraulic motor are provided, which are connected via working lines (3, 4). The hydraulic controller includes an adjustment arrangement (9) for adjusting a setting piston (12) arranged between two setting pressure chambers (10, 11) and acting upon the displacement volume of the drive hydraulic pump (2). Further, a pre-control arrangement (8) is provided which acts upon one of the setting pressure chambers (10, 11) with a setting pressure, in dependence upon the pressure difference between two control lines (6, 7). In accordance with the development according to the invention, the precontrol arrangement (8) is connected with a feed line (30) via a pressure regulation valve (56), whereby the precontrol arrangement (8), in a control position (42, 43), connects one of the two setting pressure chambers (10; 11) with the feed line (19) via the pressure regulation valve (56) and connects the respective other setting pressure chamber (11; 10) with a pressure fluid tank (17). In a neutral position (41), both setting pressure chambers (10, 11) are connected with the feed line (30) via the pressure regulation valve (56).
摘要:
A control apparatus for several drive assemblies, which consist of hydrostatic drive units, is described. The hydraulic pumps of the hydrostatic drives are driven by means of a common prime mover and are controlled in terms of output. The output control device consists of an adjusting piston, which is connected with the control element of the hydraulic pumps and upon both sides of which pressure acts, and of a spool valve which controls the pressure action on both pressure chambers at the front surfaces of the adjusting piston and upon which, on one side, the working pressure of the pumps acts and upon which, on the other side, an adjustable spring acts. In order to give priority to one of the hydraulic pumps or one of the drive assemblies and to allow sufficient output to come from the driving engine in each operating condition, there is provided a measuring piston upon which the working pressure of the priority hydraulic pump acts and which presses on a first lever which counteracts the force of the adjustable spring acting upon the spool valve of the output control apparatus.
摘要:
The invention relates to an axial piston machine (1) of swashplate construction, with two pivot bearing parts (13b, 13c), between which a gap (14) is arranged, in which a cage segment (15) is pivotably mounted with a plurality of rolling elements (13f) about a common pivot axis (13a), the cage segment (15) being guided by an elongated guide element (19) extending transversely to the gap (14) and projecting over the gap (14), and which at one of its ends has a round guide body (19c), with which it is pivotably mounted in a sliding guide (24), which is arranged on one of the two pivot bearing parts (13b, 13c) or built-on components thereof. The guide element (19) is respectively pivotably connected by a rotary bearing (21, 22) to the cage segment (15) and the other pivot bearing part (13c). In order to improve the guiding of the cage segment (15), the guide element (19) in the region of its rotary bearing (22) connected to the cage segment (15), is displaceably connected to the cage segment (15) by an elongated guide (23) in its longitudinal direction and in the region of its end region connected to the other pivot bearing part (13c) is rotatable by the associated rotary bearing (21) and rigidly connected in its longitudinal direction to the other pivot bearing part (13c).
摘要:
The invention concerns a pressure cutoff valve unit (34) with a shuttle valve (36), which has a first input connection (39) and a second input connection (40), which it is possible to connect to an output depending on the pressures at the input connections (39, 40). The shuttle valve (36) has a shuttle valve closing element (45′), which in a first end position connects the first input connection (39) to the output and in a second end position connects the second input connection (40) to the output. The shuttle valve closing element (45′) can be locked in a position between the two end positions, and in this locked position the first input connection (39) is connected to the second input connection (40).