RGB ENGINEERING

INSTALLATION EXAMPLES: FARREL SLIDEWAY INFEED - PRE 1960 VINTAGE ROLL GRINDER

COMPUTERIZED CROWNER RETROFIT SYSTEM

The photo below shows a pre tilt infeed 1955 vintage Farrel roll grinder before the crowner retrofit.  To change crowns, the operator must position the wheel at center of the roll face, select and install the correct change gears for the roll being ground, relieve the weight on the cam using the lift jack, manually adjust the cam eccentricity, and lower the wheelhead back onto the cam.

The schematic on the right shows the modifications required with the RGB crowner retrofit system, and the photos below show the same machine with these new parts installed.  The Servo Cam Actuator (SCA) utilizes the existing cam drive train to tilt the wheel in and out.  An absolute carriage position encoder is belt driven from the "drive" change gear shaft.  The new servo motor connects through a harmonic drive reducer and a Ringfeder keyless friction coupling to rotate the input worm.  The cam is preset for a fixed eccentricity large enough to provide the required infeed amount.  A LVDT provides position feedback of the tilting wheelhead to close the servo loop.  With this arrangement, the operator can set all the crown variables at the FFG computer station.  No manual adjustments are required.  A very important advantage of this design is that the original mechanical crown drive arrangement remains intact ready to be used as a standby spare if ever needed.