What type of actuator has a single piston shaft resulting in unequal working areas?

An unbalanced actuator is characterized by having a single piston shaft, which leads to differing surface areas on either side of the piston. This design creates a situation where the force exerted by the actuator can vary depending on the pressure applied, allowing for precise control in applications where torque or force needs to be varied or where a strong return force is necessary to move components.

In contrast, balanced actuators have equal areas on both sides of the piston, resulting in a symmetrical force application when fluid power is applied. Pneumatic actuators and hydraulic cylinders can be types of balanced or unbalanced actuators depending on their design, but the key defining feature of unbalanced actuators is indeed their single piston shaft that leads to unequal working areas. This distinct design is what makes unbalanced actuators particularly effective in specific applications where their unique force characteristics are beneficial.