| Patents Granted on 1981-03-?? |
Patents 1 -
7
of 7
      |
| Number | Date | Patentee | Title | Type |
| 4,253,351 | Mar. 03, 1981 | H. Allen | Cork extractor | lever cork extractors |
| 4,253,359 | Mar. 03, 1981 | D.H. Youden | Drive System for Multiple Spindle Machine Tool | metalworking power transmission |
| 4,254,895 | Mar. 10, 1981 | E.G. Cheak | Apparatus for automatic alignment and attachment of a doorjamb and stop | specialty woodworking machines |
| 4,255,861 | Mar. 17, 1981 | H. Suwa, K. Nakata | Electrically Digital Display Micrometer | micrometers |
| 4,256,295 | Mar. 17, 1981 | E.A. Egner | Adjustable Clamp | clamps |
| GB-2,056,896 | Mar. 25, 1981 | M. Orrow | Improvements in and relating to punch assemblies | punch presses |
| CH-622,203 | Mar. 31, 1981 | F. Kagerer | Device for Clamping a Tool-Spindle Sleeve Which Can Perform a Feed Movement | |
