| All Patents in class 72/20.2 |
Patents 1 -
6
of 6
      |
| Number | Date | Patentee | Title | Type |
| 1,311,942 | Aug. 05, 1919 | A. Aldridge, H. Terhune | Electromagnetically-controlled board drop-hammer | drop hammers |
| 1,531,489 | Mar. 31, 1925 | J.R. Bowie, G.P. Macready | Pneumatic drop hammer | drop hammers |
| 2,220,037 | Oct. 29, 1940 | R.P. Fitzgerald | Double-acting drop hammer | drop hammers |
| 3,142,206 | Jul. 28, 1964 | W.W. Hague, G.A. Householder | Control system for impact device | drop hammers |
| 3,180,123 | Apr. 27, 1965 | A.R. Kull | Work Transfer Mechanism for Forging Presses and the Like | forging apparatus and accessories |
| 3,282,079 | Nov. 01, 1966 | A.R. Kull | Work Handling Mechanism for Forging Presses and the Like | workpiece changers and storage mechanisms |
