What are piston pumps?
The piston pump is a stable and relatively simple device. The basket pump consists of pistons, rooms and two valves. The pump works by lowering the piston into the chamber and compressing the medium inside.
For manual pumps, this is usually air.
When the air pressure exceeds the exhaust valve spring pressure, the compressed medium flows through the open exhaust valve. When the piston is pulled back, it opens the intake valve, closes the exhaust valve, and uses suction to draw in new support for compression. Although somewhat expensive, reciprocating pumps are one of the most efficient types of pumps.
It has good pressure (up to 10,000 psi) but is susceptible to contaminants due to its design. They provide a complete solution for many high pressure hydraulic oil injection applications.
What are axial piston pumps?
Axial piston pumps are positive displacement pumps that use multiple cylinders arranged around a central axis. A group of cylinders, usually composed of odd numbers, is called a cylinder block. The piston of each cylinder is attached to a blade plate. A swash plate, also called a cam or rocker plate, is attached to the swashplate.
As the shaft rotates, the angle of the swashplate changes, causing the piston to move in and out of each cylinder.
Since the rotary plate is positioned at an angle to the axis of rotation, the piston must interact axially as it rotates about the axis of the cylinder block. The axial movement of the piston is sinusoidal. As the piston moves up, it moves towards the valve plate. At this point of rotation, the fluid trapped between the buried end of the piston and the valve plate is discharged through one of the semicircular holes in the valve plate to the discharge port of the pump.
As the piston moves back against the valve plate, the fluid is pushed through the outlet port of the valve plate.
Read Also:- What Do You Know About Internal Gear Pumps?
Axial piston pumps can be designed as variable piston pumps, which makes them very useful for controlling hydraulic motors and cylinder speed. In this design, as the pump rotates, each piston is used to affect the displacement volume to change the depth it extends into the cylinder. A pressure compensating piston is used in some models to maintain a constant discharge pressure at different loads.
Inexpensive pressure washers sometimes use flat speed models. In a typical pressure-compensated pump, the vane angle is adjusted by valve action using pressure feedback to ensure that the pump output is sufficient to maintain a given pressure. As the load flow increases, the pressure momentarily drops, but the pressure compensation valve detects the drop and increases the swashplate angle to increase the pump output to restore the required pressure.
What are their applications?
The axial pumps may contain most part of the required chain to adjust the electricity and pressure to adjust the electricity and pressure. They can be very reliable and given to their remaining parts in a very simple and cheaper form for them.
They are used to power the hydraulic systems of jet aircraft, are driven by gears in the headstock of turbine engines, and are often used in automobile air conditioning compressors to cool the cabin.
The pump’s design meets the limited weight and space requirements of vehicle engine bays and minimizes vibration. Pressure washers also use these pumps and axial piston engines are used to power many machines.
It works like an axial piston pump, except that the rotating fluid is supplied at considerable pressure and the piston housing rotates to provide shaft power to other machines.
A common use for axial piston engines is to drive small earthmoving machinery such as wheel loaders.