Gearhead/Linear Head: Gearhead Structure

The figure below illustrates the structure of a gearhead with the output shaft arranged parallel to the motor shaft. The names and roles of each part are as follows.

Backlash

The backlash is the gap between the tooth surfaces when they are interlocked, as shown in the figure below. The gap between gears is set to absorb assembly errors in the gearhead.

Backlash has no effect on unidirectional operation, but when changing the rotation direction and during positioning operations, deviation from the theoretical rotation angle is caused in degree to the size of the backlash. Therefore, in our company, for gearheads designed for high-precision positioning with stepper motors or servo motors, efforts are made to eliminate or adjust the backlash. This ensures the capability for highly accurate positioning operations.
The backlash value for each gearhead is the initial value when there is no load.

Sealing Insert Design

Our company's gearheads use grease lubrication for the gears.
The structure is designed to seal with oil seals, O-rings, gaskets, etc. depending on the consistency of the grease enclosed, and the degree of protection class when combined with the motor.
The sealing capacity of the oil seal that seals the sliding portion of the shaft varies greatly, depending on the operating ambient temperature and operation conditions, but the standard is 10,000 hours. For equipment averse to grease oil, please install an oil catcher.
We have sealed an appropriate amount of grease to prevent early damage, even if a small amount of grease occasionally exudes. Therefore, there is no need to inject additional grease.
To enhance the sealing capability of the oil seal, we are implementing the use of special oil seals in some of the gearheads.

For details, refer to the structure of each gearhead.