| Patents for Ralph D. Gardner |
Patents 1 -
10
of 10
      |
| Picture | Number | Date | Patentee | Title |
| | 1,416,952 | May 23, 1922 | R.D. Gardner | Ring-grinding machine |
| | 1,465,762 | Aug. 21, 1923 | R.D. Gardner | Double-spindle disk grinder |
| | 1,523,952 | Jan. 20, 1925 | J. Nielsen, R.D. Gardner, E.B. Gardner | Grinding machine |
| | 1,563,901 | Dec. 01, 1925 | R.D. Gardner | Grinding machine |
| | 1,651,382 | Dec. 06, 1927 | R.D. Gardner, J. Nielsen, E.B. Gardner | Grinding machine |
| | 1,659,092 | Feb. 14, 1928 | E.B. Gardner | Ring-grinding machine |
| | 1,661,330 | Mar. 06, 1928 | R.D. Gardner, J. Nielsen, E.B. Gardner | Grinding machine |
| | 1,670,111 | May 15, 1928 | E.B. Gardner | Grinding machine |
| | 2,103,074 | Dec. 21, 1937 | R.D. Gardner | Clamping device |
 | 2,107,566 | Feb. 08, 1938 | R.D. Gardner | Abrasive-sawing machine |
