Advantages of small gears in the application of machine rack and pinion transmission system

In a rack and pinion drive system, the pitch diameter of the pinion gears is critical to the system.

If the pitch diameter of the gear is reduced, the starting torque and reduction ratio required by the reducer are reduced. In addition, the gear radius is small, and the linear clearance between the gearbox and the gear is also reduced.

Another significant advantage of the pinion is that the linearity stiffness is related to the torque of the gearbox. The linearity is inversely proportional to the square of the gear diameter. Therefore, for every half of the gear diameter used, the linearity can be increased by 4 times.

Example:

The following example will give you a good idea of the advantages of using pinions.

It is necessary to move 7,000 pounds of objects at a speed of 2,000 inches per minute and accelerate at 66.67 inches per second. The acceleration is 1489 pounds. We chose a helical gear with 40 teeth and 14 teeth and a modulus of 3 to compare:

As seen from the above example, it is obvious that the starting torque required for the use of the pinion is reduced, and the reduction gearbox size and reduction ratio are correspondingly reduced. The backlash is reduced by two-thirds, the linear stiffness is increased by four times, and the resonant frequency is more than twice that of the original.