Viscous speed governor is safe and quiet

Controlling the rotation of shafts on industrial doors, fire doors, in steering and materials handling applications can cause major problems for design engineers

Problem: Controlling the rotation of shafts on industrial doors, fire doors, in steering and materials handling applications can cause major problems for design engineers, especially if they require consistent speed control through 360° of rotation in both directions and low noise output. Solution: Enidine has developed a viscous speed governor (VSG) that safely and quietly controls rotary motion. The patented device controls the rotation of shafts and hinged loads by using silicone-based viscous shearing technology. An inner rotor is surrounded by silicone fluid within the stationery housing. As the shaft rotates, the inner rotor shears the silicone fluid providing resistance and smooth motion. Fluid viscosity of each VSG is selected after considering variables such as the component size, weight, spring assist and desired cycle time. The VSG has industry standard shaft and keyway mounting configurations and can operate indoor or outdoor in temperatures from -40°C to 95°C. Ken Bradford, UK sales manager at Enidine told Eureka: "The VSG is currently in use by most major door manufacturers. It meets industry standards outlined by Underwriters Laboratory, Warnock Hersey and Factory Mutual. It has passed the three-hour fire door burn test and conforms to numerous industry standards." Applications: Applications for the VSG are numerous. In new and retrofit applications, a single VSG can be installed on rolling doors by simply mounting to the keyed door shaft as per the original door manufacturer's instructions. It requires no adjustments during installation or while in service and can control the closing and opening speed of most large doors. And multiple governors can be used to handle over-sized doors. The device could be used for the braking of free conveyor rollers and ramps; for free-fall load protection on hoists; steering control; as a limiter in the amusement industry; for the control of shafts or hinged loads in industrial safety; overhead and rolling steel fire doors; and in marine applications. DP