WordNet
n. a water pump that uses the kinetic energy of flowing water to force a small fraction of that water to a reservoir at a higher level [syn: hydraulic ram]
Wikipedia
Hydraulic pumps are used in hydraulic drive systems and can be hydrostatic or hydrodynamic. A hydraulic pump is a mechanical source of power that converts mechanical power into hydraulic energy (hydrostatic energy i.e. flow, pressure). It generates flow with enough power to overcome pressure induced by the load at the pump outlet. When a hydraulic pump operates, it creates a vacuum at the pump inlet, which forces liquid from the reservoir into the inlet line to the pump and by mechanical action delivers this liquid to the pump outlet and forces it into the hydraulic system. Hydrostatic pumps are positive displacement pumps while hydrodynamic pumps can be fixed displacement pumps, in which the displacement (flow through the pump per rotation of the pump) cannot be adjusted, or variable displacement pumps, which have a more complicated construction that allows the displacement to be adjusted. Although, hydrodynamic pumps are more frequent in day-to-day life. Hydrostatics pump which are of various types works on the principle of Pascal's law. It states that the increase in pressure at one point of the enclosed liquid in equilibrium of rest is transmitted equally to all other points of the liquid, unless the effect of gravity is neglected.(in case of statics)
Usage examples of "hydraulic pump".
He retarded the throttles experimentally, instinctively wanting to get down to about 250 knots so the emergency hydraulic pump would not have to work so hard to move the control surfaces.
The emergency hydraulic pump was designed to allow just enough control to exit a combat situation, just enough to allow the crew to get to a safe place to eject.
The canopy opened slowly, the battery driving a small hydraulic pump that whined loudly in protest.
Once a huge piece of machinery which seemed to be the valves and piston of a hydraulic pump projected itself, all rusted, from a clump of furze.
Soon the governors would burn out and without the seals so would the hydraulic pump, while the blades broke up under the stress.
Before Yaz sat a huge, disassembled gear clutch and its hydraulic pump system.
It took a little tinkering to compress the Twing-Ding down to fit between the cubes, but by about midnight I had the apparatus loaded and started the hydraulic pump to pressurize the system.
OTL fore carts vary between those that simply adapt the tractor hitch system to horse-drawn and those carts that carry a motor and/or a hydraulic pump to operate the tractor version equipment.
He tried a hand-operated hydraulic pump, but he could not regain pressure.