How to apply preload

TCG eliminates the backlash by realizing perpetual tooth-to-tooth contact. For this purpose, the application of an appropriate amount of preload against the tooth faces is required.
The insufficient amount of preload will cause backlash, and the excessive amount of preload will degrade the precision, increase the noise and the vibration, and shorten the life.
TCG is designed so that when it is mounted with the center-to-center distance given in the specifications (tolerance: 0.01mm, ambient temperature: 20ºC), the appropriate amount of preload can be obtained.
In order to obtain the appropriate amount of preload, it is recommended that the adjusting mechanism as follows should be used.

Appropriate preload amount （to ensure zero backlash）
Preload （Roller pinion pressing force）    

Models 1010 to 1210: 2kgf or less (excluding friction, etc.)
Models 1610 to 4014: 5kgf or less (excluding friction, etc.)

Center-to-center distance adjustment amount    　0 to －0.01mm
( Allowable amount: －0.02 to 0.1mm. If assembly is made in positive direction, backlash appears with amount of center-to-center displaced distance × 0.8mm.)

[Adjustment Example]
1.Measure the rack tooth height over the entire stroke and set the position according to the lowest point. Then mesh the pinion and rack while lightly pressing the pinion against the rack by hand.
The same procedure applies when using a ring.

2.Operate the system in the meshed condition and check that there are no abnormalities in positioning accuracy, running noise, or vibration.

3.Using the outer dimension A (center distance) as a reference, adjust the preload amount in the positive or negative direction using an adjustment mechanism such as a set screw.

4.Run the system again and confirm that it operates normally.