Equations have been derived for designing automatic tensioning variable speed V-belt drives. Such drives employ a screw principle to increase tension in the belt as loading of the drive increases. Adjustable tensioning makes it possible for variable speed drives to transmit significantly larger loads without overly penalizing belt life. This feature is possible because high tensions required by heavy loads are not retained during lighter loads experienced under normal operations.
Drives have been designed by these equations and have been proven successful both in the field and laboratory. Experience in designing the drives is discussed and general recommendations are provided for the design of new torque sensing drives. Other types of applications are described that would also benefit from torque-actuated tensioning.