Helac Rotary Actuator L20 Series

Helac’s innovative sliding-spline technology converts linear piston motion into powerful shaft rotation. Each actuator is comprised of a housing and two moving parts — the
central shaft and piston. Helical spline teeth on the shaft engage matching teeth on the piston’s inside diameter. A second set of helical splines on the piston’s outside diameter mesh with the gear in the housing.

Starting Position

The piston is completely bottomed out. Bars indicate starting positions of piston and shaft. The housing with integral gear remains stationary.

Ending Position

When hydraulic pressure is applied to the piston, it moves axially; while the helical gearing causes the piston and shaft to rotate simultaneously. Applying pressure to the opposite port will return the piston and shaft to their original starting positions.

For over 50 years, Helac has lead the way in actuator technology and innovation. Our extensive line of compact and powerful rotary actuators offer simple and cost-effective solutions to move, support and position rotating loads in countless applications. Helac actuators are designed to replace multiple components and function as a rotating device, mounting structure and bearing, all-in-one. They feature tremendous torque output and exceptional load bearing capability in compact dimensions.

• Powerful: High torque, high bearing capacity
• Durable: Moving parts enclosed, suitable for harsh environments
• Compact: High power density, fits in tight spaces
• Hold Position: Zero internal leakage, smooth operation, no external brake required
• Simplifies: Eliminates bearings, linkages & brackets, reduces bill of materials, simplifies supply chain, assembly and maintenance
• Backdrives in overload conditions: Hydraulic fuse,prevents mechanical damage when properly equipped

Cantilever Mount

The load is mounted to the shaft flange and is supported at only one end of the shaft. Cantilever mounting is not recommended for aerial work platforms or other critical and safety-related applications.

Straddle Mount

The load is supported at both ends of the shaft.

Manufactured from aluminum, the valve blocks are bolted to a flat mounting pad on the actuator housing. Three bolts secure the valve block to the actuator. See specification pages for valve location.The pilot ratio is 3:1. The valves are set to relieve at 3300 psi ±300 psi (228 bar ±21 bar).