A rotary actuator including a housing provided with a fluid actuated drive assembly operatively connected to a rotary plate arranged to affect the drive thereof, wherein the housing and the rotary plate are provided with complementary cooperating stop abutment and groove or track for limiting the angular rotation of the rotary plate in either the clockwise or counterclockwise rotation. An adjustment is provided to adjust the angular rotation of the rotary plate. Also provided is a control or adjustment for independently regulating the speed of rotation of the rotary plate either in the clockwise or counterclockwise rotation.An object of the rotary actuator is to provide a rotary actuator in which the rotation of the actuator is determined in a manner whereby the impact imparted on the gearing thereof is eliminated. Another object of the rotary actuator is to provide a rotary actuator wherein the precision and accuracy thereof can be maintained over a longer period of time, thereby increasing the useful life thereof. Another object of the rotary actuator is to provide a rotary actuator in which the degree of angular rotation, in either the clockwise or counterclockwise direction, can be adjusted within predetermined limits. Another object of the rotary actuator is to provide a rotary actuator wherein the speed of rotation in either a clockwise or counterclockwise direction is independently controlled. Another object is to provide a rotary actuator which is readily simple in construction, can be readily manufactured, and is more durable and accurate in use.
The foregoing objects and other features and advantages are attained by a rotary actuator that includes a housing having formed therein a pair of spaced apart piston chambers. A piston having a rack portion is reciprocally disposed in each of the piston chambers. Connected into communication with each of the respective piston chambers is a fluid inlet for directing an operating fluid medium into the associated cylinder in an alternating manner. Each of the respective piston chambers are interconnected in communication by a passageway so that fluid introduced in one of the fluid outlets will effect the displacement of the piston in each of the respective chambers. Disposed in meshing relationship with the rack of the respective pistons is a pinion gear to which a rotary plate is connected. Projecting outwardly from the housing is a stop abutment arranged to be received in a complementary arcuate groove formed in the complementary surface of the rotary plate. The arrangement is such that the angular rotation of the rotary plate is determined by the engagement of the end portion of the arcuate groove of the rotary plate with the stop abutment as the rotary plate is driven in one direction or the other. To adjust the limits of the angular rotation of the rotary plate, the ends of the groove may be defined by an adjusting screw.
