油圧式ピストンモータの性能比較に関する調査研究

Abstract

Hydraulic actuators, especially piston type motors, provide high power and rapid response. Hydraulic piston motors are divided into four types: swash plate type axial piston motor, bent axis type axial piston motor, crank type radial piston motor, and multi-stroke type radial piston motor. In this paper the performance of hydraulic piston motors has been surveyed, calculated, and evaluated on the basis of specifications listed for them in current catalogs. We selected 111 types of swash plate type axial piston motors, 98 types of bent axis type axial piston motors, 118 types of crank type radial piston motors, and 57 types of multi-stroke type radial piston motors available in the market. Mass, momentum inertia, rotation speed, rated torque, power density, and torque-inertia ratio of motors were selected as the performance indexes for comparison. It was confirmed that the piston motors show the different characteristics depending on structural type of the piston motor. In regard to the axial piston motors, the bent axis type motors showed higher performance than the swash plate type motors in almost all evaluation index. However, the newly developed small-size swash plate type motors showed almost same performance as the bent axis type motors for some evaluations.