A gerotor is a tool used for pumping liquids. This small, circular rotor's unique hydraulic design provides a smooth, consistent method for shuttling oil, water and other liquids within an enclosed tube system. This method of pumping has many benefits and is utilized by a variety of industries.
The term "gerotor" is short for "generated rotor," a tool that was invented in 1921. European engineer Myron Hill dedicated many years of his life to the development of this pump. After he had created the gerotor, he also went on to develop a great deal of geometric theory based on the use of rotors.
A gerotor has a distinctive design that is the key to its success. This circular rotor actually has a second rotor encased within it. The inner rotor has a certain number of oblong teeth and is situated off center, and the outer rotor has one more tooth than the inner rotor has. When both rotors rotate, the teeth lock together and unlock because of the off-center position, creating intermittent open pockets between the rotors during operation.
A gerotor functions as a pumping mechanism when a liquid passes through the teeth, creating a suction port. The liquid propels the rotors and spins the gears, creating suction and discharge ports whenever the teeth are meshed together. The rotation and mesh of teeth also creates a tight seal between these ports and sucks the liquid through at a consistent speed.
This type of pumping system has many advantages over traditional, motor-driven pumps. Its most obvious benefit is that its lower number of moving parts and valves keep it from breaking down as frequently as other pump systems. The consistency of a self-propelled vacuum also is beneficial because it moves liquid at one speed, based on the push of the liquid. This differs from motor-driven pumps because it requires no adjustment or monitoring to perform correctly.
Gerotor pumps are used in many industries and in many ways. The automotive industry has embraced this technology by using gerotos in everything from fuel injection systems to power steering drives. Manufacturing industries also have found ways to use these rotors, especially when oils need to be sent by tube over a great distance to lubricate machinery. Factories that produce oils, such as cooking oils, also use the vacuum-powered system to transport the goods.
By Patrick Wensink