The KNOLL Hydraulic pump is a positive displacement machine for fluid power applications, used to provide hydraulic flow to hydraulic devices such as cylinders, plungers, motors, etc. Power steering pumps in cars are an example of engine-driven rotation - vane pumps are common. The geared oil pump for an engine is another everyday example. Hydraulic pumps can also be motor-driven or manually operated. Variable displacement pumps are particularly useful because they can provide unlimited regulation in their speed range at constant input speeds.

The pump produces flow. Pressure is the resistance to flow. Centrifugal pumps can operate with clogged discharge without creating overpressure, while positive displacement pumps cannot. A hydraulic pump, like any positive displacement pump, requires overpressure protection, usually in the form of a pressure reducing valve. The overpressure relief device is usually built into the pump itself.

Hydraulic systems are used where compact power is required and where electrical, mechanical or pneumatic systems would become too large, dangerous or not up to the task. For construction equipment, hydraulic power provides the means to move heavy booms and buckets. In manufacturing, hydraulic power is used in presses and other high-force applications. The core of the hydraulic system is the pump itself, and the choice of the correct hydraulic pump depends on the expected function of the hydraulic system.

Starting with variable pumps, the main hydraulic pump types used include:

Axial piston pump

Axial piston pumps use axially mounted pistons that reciprocate within the inner cylinder to produce alternating suction and discharge flows. They can be designed as variable rate devices, allowing them to be used to control the speed of hydraulic motors and cylinders. In this design, the swash plate is used to change the depth at which each piston extends into its cylinder as the pump rotates, thereby affecting emissions. Pressure compensator pistons are used in some designs to maintain a constant discharge pressure under varying loads.

Radial piston pump

The radial piston pump arranges a series of pistons radially around the rotor hub. The rotor eccentricity is mounted in the pump housing and forces the piston in and out of the cylinder as it rotates, allowing hydraulic oil to be drawn into and then expelled from the cylinder chamber. The inlet and outlet of the pump are located in the valve of the central hub. Another design places the inlet and outlet around the pump housing. Radial piston pumps can be purchased as fixed displacement or variable displacement models. In variable displacement versions, the eccentricity of the rotor in the pump housing is changed to reduce or increase the stroke of the piston.

Vane pump

Rotary vane pumps use a series of rigid blades mounted in an eccentric rotor that sweep along the inner wall of the housing cavity to create a smaller volume that forces fluid out through the discharge port. In some designs, the volume of fluid leaving the pump can be adjusted by changing the axis of rotation of the rotor with respect to the pump housing. Zero flow occurs when the rotor and the housing axis coincide.

External gear pump

The external gear pump relies on the counter-rotating motion of the engaged external spur gear to transfer the motion to the fluid. They are usually fixed displacement designs, very simple and robust. They typically come in the form of tightly coupled designs, where the motor and pump share a common shaft and mounting. Oil flows around the pump housing between the gear teeth. On the outlet side, the meshing action of the teeth reduces the volume of the discharged oil. A small amount of oil between the remeshed gears is discharged through the bearing and returned to the suction side of the pump. External gear pumps are very popular in fixed displacement hydraulic applications because of their ability to deliver very high pressures.

Internal gear pump

The internal gear pump uses the meshing action of the internal and external gears combined with the crescent shaped sector element to generate fluid flow. The axis of the outer gear is offset from the axis of the inner gear, and when the two gears rotate, they detach and mesh to form the suction and discharge zones. This sector acts as a barrier between inhalation and discharge. Another type of internal gear pump, the cycloidal pump, uses meshed cycloidal gears to achieve the same suction and discharge areas without the need for sector elements.

The above content introduces the type of KNOLL hydraulic pump and what the working principle is. In addition, Shenzhen Oudejie Technology specializes in selling new original German imported KNOLL Kono pump, and promises to sell products are new original imported, while providing our customers with quotation, selection, product information and other services.