Previous RFQ Page Next Index Page Home Page This section will introduce most of the more common types of drive mechanisms found in linear motion machinery. Ideally, a drive system should not support any loads, with all the loads being handled by a bearing system. Topics discussed will include, but not be limited to, the mechanism of actuation, efficiency, accuracy, load transfer, speed, pitch, life cycle, application and maintenance. Each type of drive system will be accompanied by a diagram and useful equations when applicable | Previous RFQ Page Next Index Page Home Page Technical Information 5 Ball and Acme Screw Drive Mechanisms This section will introduce most of the more common types of drive mechanisms found in linear motion machinery. Ideally a drive system should not support any loads with all the loads being handled by a bearing system. Topics discussed will include but not be limited to the mechanism of actuation efficiency accuracy load transfer speed pitch life cycle application and maintenance. Each type of drive system will be accompanied by a diagram and useful equations when applicable. Some of the terms used with screws the most common drive component are as follows 1 Technical Information lead pitch advance of the nut along the length of the screw per revolution distance between corresponding points on adjacent thread forms pitch lead of starts of threads of starts outer diameter root diameter stub number of teeth found along a unit length of the screw 1 pitch number of helical grooves cut into the length of the shaft largest diameter over the threaded section at top of threads smallest diameter over the threaded section at base of threads specific type of ACME thread where the root diameter is larger to provide for a more heavy-duty screw the threads look stubby critical shaft speed operating speed of spinning shaft that produces severe vibrations during operation. This is a function of length diameter and end supports. maximum compressive load maximum load that can be axially applied to the screw before buckling or permanent deformation is experienced. Also referred to as column strength. end bearing supports the screw must be supported at one or both ends with thrust type bearings. Depending upon the application it may also be desirable to provide for a stiffer system by incorporating angular contact bearings fixed support . Although shafts gear trains belt and pulley rack and pinion and chain and sprocket drives are practical in other applications they require special
