Model RG Linear Drive With Adjustable Pitch

Jan. 10, 2013

All Model RG linear drives now feature a manual pitch control which permits a 10:1 adjustment of the linear pitch of the drive unit. Each of the 17 Model RG drive units has a specific maximum linear pitch. This is the linear distance the drive will move on the shaft per one revolution of the shaft. The pitch control lets users turn the pitch down in 0.01 increments across one hundred discrete settings. For example, the model RG30 drive has a maximum pitch of 26.0 mm (1.02 inches) and may be turned down to 2.6 mm (0.10 inches). 


In applications where it is desirable or necessary to keep the drive motor running at a constant speed, the adjustable pitch feature enables a variable-speed drive system without requiring changes or adjustments to the drive motor speed. If greater linear speed changes are needed than are afforded by the pitch control, then the drive motor speed may be increased or decreased without affecting the linear pitch of the drive. Once the pitch of the drive is set, it will remain the same regardless of the drive motor speed. The pitch will change only if the operator adjusts the pitch control. In applications where a specific linear pitch range is required, the traverse shaft may be driven via belt and pulley linkage to the main drive shaft. The ratio between the two pulleys establishes the desired linear pitch range. For example, if the pulley on the traverse shaft is twice as large as the pulley on the main drive shaft then the drive will move two times its normal pitch per one shaft revolution. 


Using proprietary software and based on application data, Amacoil technical support personnel can quickly calculate the correct pulley ratio to give the desired linear pitch range. Adjustable linear pitch is possible with Uhing Model RG drives because of the rolling ring-bearing assembly housed inside the drive unit. The angle of the bearing assembly relative to the shaft is adjustable via the pitch control. Turning the pitch control changes the bearing angle which changes the drive's pitch causing the unit to move faster or slower per one shaft revolution. This effectively changes the linear speed of the drive unit independently of drive motor speed. A variable speed system may, therefore, be free of clutches, cams, gears and so forth. In most cases this design permits the use of a relatively inexpensive, single-speed, unidirectional drive motor. Uhing rolling ring linear drives are used in production machinery for processes such as positioning, scanning, cutting, measuring, winding, and spraying. Applications exist in a variety of automated manufacturing industries including textile, automotive, wire/cable production, metrology and CNC machining. Uhing linear drive assemblies feature zero backlash and a jam-proof, smooth shaft. As the exclusive North American distributor for Uhing, Amacoil provides sales, technical support, service/repairs and parts. 

  • Axial Thrust (max.): 800 lb.
  • Linear Pitch: Variable
  • Zero Backlash