US Patent: 3,840,791
|
| Alleviation of Delays and Inaccuracies in Machining by the Constant Surface Feet Per Minute Mode
|
|
Patentee:
|
|
| William H. Mack (exact or similar names) - North Fond du Lac, Fond du Lac County, WI |
| Manufacturer: |
| Not known to have been produced |
|
|
Patent Dates:
|
| Applied: |
Feb. 26, 1973 |
| Granted: |
Oct. 08, 1974 |
USPTO (New site tip)
Google Patents
Report data errors or omissions to steward
Joel Havens
"Vintage Machinery" entry for Giddings & Lewis Manufacturing Co.
|
|
Description: |
| Abstract:
Methods and apparatus for causing a turning machine tool to operate with selectable but "constant surface feet per minute" (CSFM) under the control of an iteratively computing numerical control director, and characterized by anticipation of the necessary spindle or table r.p.m. which will be required at the start of a cut, such that as the cutter is rapidly approaching a workpiece, the spindle or table is accelerated to that required speed, thereby to substantially eliminate the delay which would be necessary to wait for the required speed to be reached with spindle or table servo motors of limited power driving loads with high inertia. The invention is specifically embodied in methods and apparatus for substituting (in lieu of signals representing the actual radius of the cutter from the workpiece center) signals representing the radial distance from the work center which the cutter will reach at the end of a rapid traverse positioning motion and while that positioning motion is being executed in the steps and apparatus by which the table or spindle speed is made inversely proportional to a signaled radius value. |
|
