The swash plate type block is a model of a swash plate mechanism in which an axial piston hydraulic pump and a motor are used to convert a translational motion of a piston into a rotational motion of a drive shaft. The mechanism is a cylinder block or a rotor, a combination of a piston inside, and an angled swash plate. The angular position of the plate is controlled by an actuator, usually a servo cylinder, acting along the line of action of the actuator. The distance between the actuator line and the swashplate at zero angle is equal to the length of the actuator arm. The piston breaks off the swashplate by offsetting. The swashplate angle can be changed to increase or decrease the piston stroke. When the rotor rotates, the piston slides on the swashplate, which causes the piston to reciprocate. The sliding contact between the piston and the swash plate is maintained by a guide rail as shown in the figure.
In a hydraulic press, the piston moves along a slot in the port plate and is therefore periodically connected to the air intake or exhaust port of the machine. This model simulates a single piston interacting with a swash plate piston pump . Mechanically, the mechanism performs the sum of two movements caused by the rotation of the swash plate relative to its axis and the rotation of the rotor, and converts them into displacements of the piston. Assume that the positive direction of the actuator points to the left from the vertical axis and the positive direction of the piston movement points upwards, as shown in the figure. The two moving reference points correspond to a plate perpendicular to the rotor axis. For angular motion of the rotor, clockwise rotation is assumed to be positive.
An example of a hydraulic swashplate piston pump with load sensing and pressure limit control simulates a test bench to study the interaction between an axial piston pump and a typical control unit while performing load sensing and pressure limiting functions. In order to ensure the required accuracy, the pump model needs to take into account the characteristics of the interaction between the piston, swash plate and port plate, which makes it necessary to build a detailed pump model.