VARIABLE STROKE MOTOR AND VALVE

摘要

A fluid valve shaft (16) is provided for a variable stroke motor (10). The valve shaft (16) has a housing (12) forming a cylinder (14), a first fluid input (18) into the cylinder (14), a first fluid output (20) out of the cylinder (14), a second fluid input (22) into the cylinder (14), and a second fluid output (24) out of the cylinder (14). Provided within the cylinder (14) is the valve shaft (16) provided with slots (26), (28), (90) and (92). As the valve shaft (16) rotates into a first position, fluid communication between the first fluid input (18) and the first fluid output (20) is shut off, while fluid communication between the second fluid input (22) and second fluid output (24) is opened. As the valve shaft (16) rotates to a second position, communication between the first fluid input (18) and first fluid output (20) is opened, while the communication between the second fluid input (22) and the second fluid output (24) is shut off. The device is preferably hooked up to a drive cylinder (48) in fluid communication with the first fluid output (20) and the second fluidinput (22). A piston (52) is provided within the drive cylinder (48). A fluid supply is operably coupled to the first fluid input (18) and means (42) are provided for rotating the valve shaft (16) at a constant speed. As pressure of the fluid increases, the stroke of the piston (52) increases, thereby generating a longer piston stroke, while the speed of the rotating valve shaft (16) remains constant.