Chatter free gear driven cam actuated vacuum pump

摘要

A vacuum pump having a cam actuated spring-biased pumping element and a gear for rotatably driving the cam has a torque counterbalancing spring and plunger device engaging the cam in a position out of phase with the pumping element and arranged to apply counterbalancing torques that prevent the application of torque reversals to the gear and thus avoid gear oscillation and chatter.