A10VSO pump

The A10VSO pump is a swashplate-type axial variable displacement piston pump commonly used in open-loop hydraulic systems. Below is a detailed explanation of its operating principle:

First, Basic Structure

The A10VSO pump primarily consists of the pump housing, cylinder block, pistons, swashplate, distributor plate, drive shaft, and other components. The cylinder block is mounted within the pump housing and rotates driven by the drive shaft. Multiple pistons are evenly distributed within the piston bores of the cylinder block, capable of reciprocating motion within these bores. The swashplate is mounted at a specific angle relative to the cylinder block's axis. The distributor plate is fixed to the pump housing and positioned on one side of the cylinder block.

Second, Working Principle

1. Suction Process

When the prime mover drives the drive shaft to rotate, the cylinder block rotates accordingly. Due to the angle between the swash plate and the cylinder block axis, the plungers perform reciprocating motion within their bores while rotating with the cylinder block. As a plunger moves from the farthest point to the nearest point relative to the swash plate, the volume of its chamber gradually increases, creating a local vacuum. At this point, the suction port on the distributor plate connects to this piston chamber. Hydraulic fluid from the reservoir enters the piston chamber through the suction inlet and the distributor plate's suction port under atmospheric pressure, completing the suction process.

2. Pressure Fluid Process

As the cylinder continues rotating, the piston moves from the closest to the farthest point on the swashplate, gradually decreasing the volume of the piston chamber. At this point, the discharge port on the distributor connects to this piston chamber. The hydraulic fluid within the piston chamber is compressed, increasing pressure. The fluid then exits through the distributor's discharge port and the pump's outlet, entering the hydraulic system to supply pressurized oil, completing the discharge process.

3. Flow Regulation Principle

Flow regulation in the A10VSO pump is achieved by altering the swashplate's tilt angle. A larger swashplate angle increases the piston stroke per cylinder rotation, resulting in a larger volumetric change within the piston chamber. This, in turn, increases the pump displacement and output flow rate. Conversely, a smaller swashplate angle reduces both displacement and output flow. By adjusting the swashplate angle through the control mechanism, the pump achieves stepless flow regulation to meet varying hydraulic system flow demands under different operating conditions.

Third, Operational Characteristics Under Different Control Modes

The A10VSO pump supports multiple control modes, such as pressure control (DR) and load-sensing control (DFR). Taking pressure control as an example: when system pressure reaches the set value, the control mechanism automatically reduces the swashplate angle based on pressure feedback signals. This decreases the pump's output flow rate, matching the pump's output power to the system load. This achieves energy savings and protects the system.

Rexroth A10VSO series 31

A10VSO manual