| Patents for John Armstrong |
Patents 1 -
7
of 7
      |
| Number | Date | Patentee | Title | Type |
| 499,508 | Jun. 13, 1893 | W.C. Redfield, J.C. Booth | Pipe Wrench | chain and strap wrenches |
| 700,865 | May 27, 1902 | J. Armstrong, S. Welter | Cutting Tool | |
| 707,472 | Aug. 19, 1902 | J. Armstrong, S. Welter | Tool Holder | metal planer tool holders |
| 725,019 | Apr. 14, 1903 | J. Armstrong | Tool Holder | lathe tool holders and tool posts |
| 745,758 | Dec. 01, 1903 | S. Welter, J. Armstrong | Slotting Machine Tool Holder | slotting machine tool holders |
| 779,516 | Jan. 10, 1905 | J. Armstrong | Process of Cuttting Self Hardening Steel | |
| 1,155,542 | Oct. 05, 1915 | E.B. Bennett, J. Armstrong | Combined Gage and Compass | trammels |
