Valve actuator

Abstract

A valve actuator for converting linear motion to rotary motion comprising: a housing; a force transmitting member disposed in the housing responsive to pressure applied to one side thereof for travel between first and second terminal positions; a rod member connected to the force transmitting member for reciprocal movement between first and second terminal positions in response to travel of the force transmitting member between its terminal positions; and a crank member connected to the rod member and rotatable in response to reciprocal movement of the rod member, about an axis substantially perpendicular to the axis of the rod member, through an angle of a preselected value. The crank member is provided with first and second pivot connections, at positions radially spaced from the crank axis, by which the rod member may be alternately connected to the crank means for changing the amount of rotational response of the crank member without altering the amount of reciprocal response of the rod member to the travel of the force transmitting member.

Dependencies are inferred from the claim text.