Rack-and-Pinion Drives Often Top Other Drives For Durability, Efficiency, and Economics

Wittenstein RAPLinear motors, ball screws, and rack-and-pinion drives are good options when it comes to electro-mechanical linear motion systems. Ball screws are very popular, and linear motors are noted for precision and dynamic performance. Rack-and-Pinion drives are often overlooked when it comes to accuracy and performance, but they cannot only match but exceed what is offered by competing hardware. This is made possible through the advances in precision manufacturing, and the recent advent of electronic preloading. In fact, rack-and-pinion units often top the others in terms of durability, efficiency, and economics.

You might ask, how is this possible? Rack-and-pinion systems convert rotary motion to linear motion. A pinion engages a geared rack which moves the pinion and gearbox back and forth along the rack as the pinion rotates. The advantages to this include unlimited travel length, and backlash free operation in dual drive systems with electronic preloading. One of the biggest benefits over other designs is its lower costs because of unlimited travel length. Travel is only limited by the length of the rack, and rack sections can be linked together end-to-end to increase travel length.

Rack-and-pinion actuators have high force capacity, and they are capable of high acceleration rates and peak speeds nearly as high as linear motors. Ball screws cannot accelerate like rack-and-pinion sets, nor can they maintain the same speeds. Their stiffness is lower and less constant. Rack-and-pinion units have lower mass moment of inertia and higher natural frequency and efficiency over ball screws.

Rack-and-pinion drives boast efficiencies as high as 97%. In comparison, linear motors generally have overall efficiencies of 85%, though some are considerably lower. Ball screws, depending on if they preloaded, can have efficiencies up to 90%.

Typical rack-and-pinion applications include gantry, transport, and packaging machines that carry from a few pounds to several tons. Next generation rack-and-pinion sets are also used in woodworking, high-speed metal cutting, and assembly machines.

Wittenstein’s Rack-and-Pinion Drives Alpha Value Lines are competitively priced. They are in stock and ready to ship from their manufacturing facility immediately. For the fastest delivery, you can use the rack-and-pinion drives with their linear systems designed with inline gearheads. For more information, please contact your McNaughton-McKay representative to assist with your questions and purchases.