US Patent 8241320 Surgical instrument

An articulated surgical instrument includes a handle, an actuating assembly associated with the handle, and a shaft including a proximal end coupled to the handle, a deflectable portion and an end effector. Distal portions of deflection wires are connected to the shaft. Proximal portions of the wires are connected to the actuating assembly. Movement of the actuating assembly moves the deflection wires to cause a deflection of the deflectable portion. The actuating assembly includes one or more actuators and one or more slider members associated with the actuators and connected to the deflection wires. The slider members are movable linearly between first and second positions, the proximal portions of the deflection wires being connected to the slider members. One of the actuators and slider members has a cam track and the other has a cam follower, such that movement of an actuator by the user of the instrument causes a linear movement of a slider member from its first position to its second position, so as to move the deflection wires causing a corresponding deflection of the deflectable portion.