AN APPROACH TO ENERGY CONSERVATION FOR AIR MOTOR

Abstract

There are many methods to improve actuator efficiency in pneumatic systems. In this research, the authors remodeled rotary valve of radial piston type air motor. During forward rotation, increasing Cut-off ratio of rotary valve which controls supply and exhaust timing can increase expansion process in this motor. As a result, air consumption was reduced, torque was increased and efficiency that we define as the ratio of air consumption to torque was improved. And the authors clarified the existence of an optimum angle in Cut-off ratio.
Considering practical utilizations, performance of this motor is demanded for the same forward rotation as backward rotation. But actually, increasing Cut-off ratio increases compression process andderives efficiency worse.
So the authors have proposed to remodel the casing of this motor in addition to increasing Cut-off ratio. This remodeling makes this motor the same performance forward rotation as backward rotation, but clearance volume expands. So the rate of increasing efficiency under this condition is less than under only remodeling Cut-off ratio. But we directed to possibility of improving efficiency.