Expanding clutches and brakes

How constricting elements work​

Airflex expanding drum clutch and brake elements use a rugged, tire-like neoprene and cord tube that expands radially outward when pressurized. The expansion forces a friction surface against an inner cylindrical drum to create torque..​

Force applied at maximum radius from axis​

Instead of the reduced radius that occurs in plate clutches, expanding clutches concentrate the frictional force on the inside drum diameter to achieve maximum torque. The radius acts as the torque lever arm to generate and apply force uniformly around the circumference.​

Uniform contact velocity​

In Airflex expanding clutches and brakes, friction shoe contact occurs across the cylindrical surface of the drum where the contact velocity is constant. This is an advantage over plate-type clutches where the contact velocity varies across the friction plate face.​

Fast and continuous heat dissipation​

Heat generated at the inner drum surface quickly travels to the drum's exposed outer surface area where it dissipates by radiation and convection. This feature is ideal for slip clutch and tension brake applications where heat needs to be continuously dissipated.​

Self-adjusting to compensate for wear​

As friction surfaces wear, the tube simply expands farther as needed. Normal wear does not reduce torque capacity.​

No lubrication required​

Expanding clutches and brakes do not need lubrication because they lack close-fitting sliding components.​

Operates in any plane​

Unlike plate clutches that operate best in a vertical plane, an expanding design combined with its centrifugal effects allows for clutch operation in any plane.