The invention discloses an axial
piston variable pump with four oil ports and low-
noise parallel distribution structure. The pump comprises a shell, a
front cover, a rear cover, a main shaft, a
swash plate cradle, a set plate, a
cylinder block, a valve plate, pistons, sliding shoes, a bearing, a variable control mechanism, etc. The
cylinder block of the pump is provided with ten
piston holes divided into two groups, and each group includes five
piston holes located on different reference circles respectively; the pistons are fit to the piston holes of the
cylinder block; the center of the cylinder block is provided with a spline hole, and the main shaft penetrates through the cylinder block, and is fit to the spline hole; a friction pair is formed by the distribution end surface of the cylinder block and the valve plate, and another friction pair is formed by the sliding shoes of the pistons in the piston holes of the cylinder block and the
swash plate cradle; the upper distribution plane of the rear cover is in static connection with the corresponding end surface of the valve plate; the valve plate adopts a window structure of inner and outer ring distribution, and
oil absorption and
discharge distribution windows are of parallel double-ring structures which are symmetrical by taking the connecting line passing a
top dead center and a bottom dead center as an axis; the rear cover is provided with four oil ports which are independent respectively; and the
piston pump has different working
modes through combining the four oil ports.