To use a rolling ring drive, the shaft extension must be coupled to a drive source. The drive source may be a motor or the Uhing shaft may be belted to another shaft.
Regardless, the gear ratio between the drive source and the Uhing shaft is critical to establishing the correct linear pitch range for the Uhing drive unit.
In the example below, the Uhing shaft is being driven via belt linkage to spool shaft.
Each Uhing Model RG linear drive has a specific maximum linear pitch (distance of travel per one shaft revolution).
The pitch control lever on the RG drive unit enables a 10:1 turndown range on the maximum linear pitch. Simply move the pitch control lever to change the linear pitch.
For example, the Model RG3-15-2MCRF drive unit has a maximum linear pitch (pitch control lever set at #10 on scale) of 0.44”. Using the pitch control lever permits turning down the pitch from 0.45” to 0.04”.
To make the maximum linear pitch greater than 0.45”, wheel A in the illustration above must be smaller than wheel B. To make the maximum linear pitch less than 0.45”, wheel A must be larger than wheel B.
For example, suppose 0.225” is the desired maximum pitch of a Uhing RG3-15-2MCRF drive unit. wheel A then must be one half the size of wheel B. The gear ratio of the Uhing shaft to the spool shaft is then 0.5 :1 and the RG3-15-2MCRF unit will move 0.5 x 0.45” or 0.225” per shaft revolution. Once the correct gear ratio is established, it remains set regardless of drive motor speed.