Operating modes of drives
are the same (1st quadrant). On hydrostatic displacement machines this situation represents normal pump/motor operation. With two quadrant operation either the direction of the torque remains the same and [...] with a changing direction of torque (driving and braking, 3rd and 4th quadrant). Example: hydraulic pump that becomes a motor due to the pull from the load. With four quadrant operation the drive operates
Pressure losses due to throttles
is a cross-section constriction). Another type of throttle loss occurs if in a system with constant pump the speed control is undertaken via flow valves ( control with throttle ). The losses that result
Idle circulation valve
Valve with the task of switching circulating the pump flow rate back to the container without pressure if it is not needed. In order to keep power losses low in doing so, this takes place on the shortest
Radial gap compensation
To reduce the leakage losses, the ring gear of an internal gear pump is pressed against the internal gear and a sickle-shaped body is placed between the ring gear and internal gear, minimising the play
Corner power
Highest hydrostatic power of a pump/motor/ transmission that is given by the max. flow rate and the max. pressure (Figure E 1) : P E = Q max · p max = M 2 · 2πn 2. On constant pumps and variable pumps
Pressure regulator (zero-stroke regulator)
Fixture which changes the flow rate of a variable pump in such a way that is becomes ever smaller as the pressure increases (e.g. up to around 5% of Q max). The pressure at which adjustment starts is
Inlet pressure
if the fluid feed height is not positive. Min. and max. inlet pressure are dependent on the type of pump. On hydrostatic displacement units the min. inlet pressure is, as a rule, limited by the occurrence
Control springs
valve control spool of a continuously adjustable valve or on the adjustment piston of a hydraulic pump ( Figure R 15 ).
Internal feedback control
feedback can be provided. Similar device-internal feedback controls are also used in flow valves or pump adjustments .
Flow division
three possible options for flow division to supply multiple consumers in a defined ratio from one pump: The most commonly used is the flow divider (valve) with two subflows. In the case of multiple subflows