Axial piston pumps are typically composed of main components such as the cylinder block, distribution plate, pistons, and swashplate. The cylinder block contains multiple pistons arranged axially, meaning the pistons' centerlines are parallel to the drive shaft's axis, hence the name "axial piston pump." However, it differs from reciprocating piston pumps as its pistons not only move reciprocally within the pump cylinder but also rotate relative to the cylinder and swashplate. The pistons make contact with the swashplate via a spherical tip. The distribution plate features high and low-pressure crescent-shaped grooves, separated by walls to ensure a certain degree of sealing. These grooves are connected to the pump's intake and outlet ports. There is an inclination angle between the swashplate's axis and the cylinder block's axis.

The working principle of an axial plunger pump: As the motor drives the transmission shaft to rotate, the pump cylinder and the plunger rotate together. The plunger head remains in contact with the inclined plate, which forms an angle with the cylinder body. Thus, as the cylinder rotates, the plunger reciprocates within the pump cylinder. Taking a single plunger as an example, as it rotates from 0° to 180°, it reaches the position of the plunger above, and the volume of the plunger cylinder gradually increases, causing liquid to be drawn into the cylinder through the intake port 'a' of the oil distribution disk. When the plunger rotates from 180° to 360°, the volume of the plunger cylinder gradually decreases, and the liquid in the cylinder is discharged through the outlet of the oil distribution disk. As long as the transmission shaft continues to rotate, the pump operates continuously.

Altering the angle of the tilting element adjusts the stroke length of the plunger within the pump cylinder, thereby changing the pump's flow rate. A pump with a fixed tilt angle is called a fixed-displacement pump, while a pump with an adjustable tilt angle is known as a variable-displacement pump.

Axial plunger pumps are available in two types, depending on the inclined element:斜盘式 and 斜轴式.

The helical plate design features a tilted cylinder relative to the helical plate, causing the piston to reciprocate within the pump cylinder. The shaft axis and cylinder axis align. This structure is simple and has a high rotational speed, but stringent working conditions are required, as the contact point between the piston end and the helical plate is often a weak link. The helical shaft design has a helical plate axis aligned with the shaft axis. It operates due to the cylinder's tilt relative to the shaft axis, causing the piston to reciprocate. Flow regulation is achieved by adjusting the angle of the swinging piston cylinder, hence sometimes referred to as swing cylinder type. Compared to the helical plate design, it is more reliable, has a larger flow rate, but is more complex in structure.

Axial piston pumps are commonly used in the hydraulic transmission systems of machine tools, metallurgy, forging, mining, and lifting machinery, and are particularly widely applied in high-power hydraulic transmission systems. To enhance efficiency, gear pumps or vane pumps are often used as auxiliary oil pumps in their application, providing oil, compensating for leaks, and maintaining a certain pressure in the oil circuit.