Radial piston motors produce very high torque at low speed. They are used as wheel motors for large equipment. Pistons operate in radial bores in…
Category: Hydraulic Pumps
Bent axis motors were developed to improve the operating and stall torque efficiencies of high-speed motors. The design (Fig. 5.15) operates in a manner similar…
Before beginning our discussion of closed-loop hydrostatic transmissions, it is necessary to first learn how a servo-controlled pump operates. A variable displacement axial piston pump…
The principle of operation of the radial piston pump is shown in Fig. 4.16. In this case, the cylinders are positioned radially around the axis…
The axial piston pump has a series of cylinders (typically 7 or 9) mounted parallel to the axis of rotation. (The arrangement is similar to…
A vane pump (Fig. 4.7) has a series of vanes that slide back and forth in slots. There are springs in these slots that push…
Variable displacement pump circuits are called demand flow circuits. A simple example is shown in Fig. 4.6. (The astute reader will quickly observe that this…
A simple circuit with fixed displacement pump is shown in Fig. 4.3. Circuits with fixed displacement pumps are called constant-flow circuits. The key concept is…
Vane and piston pumps are available as fixed or variable displacement pumps. If the cam ring is fixed in position (vane pump), or the swashplate…
The simplest and most robust positive displacement pump, having just two moving parts, is the gear pump. Its parts are non-reciprocating, move at constant speed…