| All Patents in class 72/220 |
Patents 1 -
8
of 8
      |
| Number | Date | Patentee | Title | Type |
| 6,332X | Jan. 11, 1831 | G. Stoudinger | Springs, edging and drawing steel points | steel maker |
| 16,337 | Jan. 06, 1857 | J.J. Laubach | Grooving Sheet-Metal | sheet metal |
| 78,486 | Jun. 02, 1868 | W. Serviss | Machine for Grooving Sheet Metal | grooving machines |
| 98,002 | Dec. 14, 1869 | R. McChesney, D. Wilcox | Improved machine for making carriage-clips | |
| 128,287 | Jun. 25, 1872 | R. Crooker | Improvement in machines for straightening rolled-metal plates | metal straightening machines |
| 407,530 | Jul. 23, 1889 | T.W. Irwin | Machine for Shaping Sheet Metal | sheet metal brakes |
| 450,463 | Apr. 14, 1891 | G. Kennedy | Grooving Machine Attachment | grooving machines |
| 924,828 | Jun. 15, 1909 | S.A. James, J.A. Pittman | Pipe Joining Machine | pipe making machines |
