They run quieter than the straight, especially at high speeds
They have an increased contact ratio (the number of effective teeth engaged) than straight, which increases the load carrying capacity
Their lengths are great round numbers, 
e.g. 500.0 mm and 1,000.0 mm, for easy integration with machine bed lengths; Directly racks lengths are always a multiple of pi., e.g. 502.65 mm and 1005.31 mm.
A rack and pinion is a type of linear gearrack china linear actuator that comprises a pair of gears which convert rotational movement into linear movement. This mixture of Rack gears and Spur gears are generally known as “Rack and Pinion”. Rack and pinion combinations tend to be used as part of a simple linear actuator, where the rotation of a shaft powered by hand or by a electric motor is changed into linear motion.
For customer’s that require a more accurate movement than ordinary rack and pinion combinations can’t provide, our Anti-backlash spur gears are available to be utilized as pinion gears with our Rack Gears.
The rack product range includes metric pitches from module 1.0 to 16.0, with linear force capacities as high as 92,000 lb. Rack styles include helical, straight (spur), integrated and round. Rack lengths up to 3.00 meters can be found standard, with unlimited travels lengths possible by mounting segments end-to-end.
Helical versus Directly: The helical style provides several key benefits more than the directly style, including:
These drives are perfect for a wide range of applications, including axis drives requiring precise positioning & repeatability, traveling gantries & columns, pick & place robots, CNC routers and material handling systems. Large load capacities and duty cycles may also be easily taken care of with these drives. Industries served include Materials Managing, Automation, Automotive, Aerospace, Machine Device and Robotics.
Timing belts for linear actuators are usually made of polyurethane reinforced with internal metal or Kevlar cords. The most typical tooth geometry for belts in linear actuators is the AT profile, which has a large tooth width that provides high resistance against shear forces. On the driven end of the actuator (where in fact the electric motor is certainly attached) a precision-machined toothed pulley engages with the belt, while on the non-driven end, a set pulley simply provides assistance. The non-powered, or idler, pulley is often used for tensioning the belt, although some designs offer tensioning mechanisms on the carriage. The kind of belt, tooth profile, and applied stress pressure all determine the force that can be transmitted.
Rack and pinion systems used in linear actuators consist of a rack (also referred to as the “linear gear”), a pinion (or “circular equipment”), and a gearbox. The gearbox really helps to optimize the velocity of the servo electric motor and the inertia match of the machine. The teeth of a rack and pinion drive could be directly or helical, although helical teeth are often used because of their higher load capacity and quieter procedure. For rack and pinion systems, the utmost force that can be transmitted is certainly largely determined by the tooth pitch and the size of the pinion.
Our unique knowledge extends from the coupling of linear system components – gearbox, electric motor, pinion and rack – to outstanding system solutions. We offer linear systems perfectly made to meet your unique application needs in terms of the simple running, positioning accuracy and feed pressure of linear drives.
In the study of the linear movement of the apparatus drive mechanism, the measuring platform of the apparatus rack is designed to be able to measure the linear error. using servo engine straight drives the gears on the rack. using servo electric motor directly drives the apparatus on the rack, and is based on the motion control PT point setting to understand the measurement of the Measuring range and standby control requirements etc. In the process of the linear motion of the gear and rack drive system, the measuring data is obtained by using the laser interferometer to measure the placement of the actual movement of the apparatus axis. Using the least square method to solve the linear equations of contradiction, and also to lengthen it to any number of moments and arbitrary quantity of fitting functions, using MATLAB development to obtain the real data curve corresponds with design data curve, and the linear positioning precision and repeatability of gear and rack. This technology can be prolonged to linear measurement and data evaluation of nearly all linear motion system. It may also be used as the foundation for the automatic compensation algorithm of linear movement control.
Consisting of both helical & directly (spur) tooth versions, in an assortment of sizes, components and quality levels, to meet nearly every axis drive requirements.