The present application discloses a testing device and a testing method for multiple piston assembly of a cam-lobe hydraulic motor. N cylinder blocks are installed on the cylinder block base, and piston assemblies to be tested are installed on the cylinder blocks. A driving plate is installed on the cylinder block base, and N uniformly-distributed driving plate clamping grooves are formed in the driving plate. A cylinder block protrusion is arranged at the bottom of each cylinder block, and the cylinder block protrusions are clamped in the driving plate clamping grooves. When the driving plate is rotated, the N driving plate clamping grooves drive the N cylinder blocks to rotate synchronously through the cylinder block protrusions, to synchronously change the pressure angle between a driving shaft and each piston assembly.

The present application discloses a testing device and a testing method for multiple piston assembly of a cam-lobe hydraulic motor. N cylinder blocks are installed on the cylinder block base, and piston assemblies to be tested are installed on the cylinder blocks. A driving plate is installed on the cylinder block base, and N uniformly-distributed driving plate clamping grooves are formed in the driving plate. A cylinder block protrusion is arranged at the bottom of each cylinder block, and the cylinder block protrusions are clamped in the driving plate clamping grooves. When the driving plate is rotated, the N driving plate clamping grooves drive the N cylinder blocks to rotate synchronously through the cylinder block protrusions, to synchronously change the pressure angle between a driving shaft and each piston assembly.