Rack and pinions are used for lifting mechanisms (vertical movement), horizontal motion, positioning mechanisms, stoppers and to let the synchronous rotation of many shafts generally industrial machinery. On the other hand, also, they are found in steering systems to improve the direction of cars. The features of rack and pinion systems in steering are as follows: simple structure, high rigidity, little and lightweight, and superb responsiveness. With this system, the pinion, mounted to the steering shaft, is definitely meshed with a steering rack to transmit rotary motion laterlly (Spur Gear Rack transforming it to linear movement) to ensure that you can control the wheel. In addition, rack and pinions are utilized for several other purposes, such as playthings and lateral slide gates.
As a mechanical element to transfer rotary into linear motion, gear racks tend to be compared to ball screws. There are pros and cons for using racks instead of ball screws. The benefits of a gear rack are its mechanical simplicity, huge load carrying capacity, no limit to the space, etc. One drawback though is the backlash. The benefits of a ball screw are the high precision and lower backlash while its shortcomings include the limit in length due to deflection.
There are applications where the gear rack is stationary, as the pinion traverses and others where the pinion rotates upon a fixed axis while the gear rack moves. The previous is used broadly in conveying systems as the latter can be used in extrusion systems and lifting/lowering applications.
To provide many variants of rack and pinion, KHK has many types of equipment racks in stock. If the application requires a long length requiring multiple gear racks in series, we have racks with the tooth forms correctly configured at the ends. These are described as “equipment racks with machined ends”. When a equipment rack is created, the tooth cutting procedure and heat treatment process can cause it to try & go out of true. We are able to control this with particular presses & remedial processes.