| Patents for Alexander F. Roberts |
Patents 31 -
45
of 69
      |
| Number | Date | Patentee | Title | Type |
| 81,450 | Aug. 25, 1868 | A. Wirsching | Improvement in watchmaker drills | watchmaker |
| 81,649 | Sep. 01, 1868 | A. Kipp, Jr. | Improvement in steam and fire-regulators | stationary boilers |
| 81,708 | Sep. 01, 1868 | J. Uhl | Improvement in saw-set | saw sets |
| 83,045 | Oct. 13, 1868 | J.C. Crumpton | Improvement in Vises | bench vises |
| 85,372 | Dec. 29, 1868 | J. Elliott | Pipe and Faucet Clamp | |
| 86,001 | Jan. 19, 1869 | C.W. Coe | Improved drilling and bolt-tapping machine | drill presses |
| 88,109 | Mar. 23, 1869 | J. Woodville | Improvement in plane-guide | jointer gauges |
| 89,925 | May 11, 1869 | J.S. Fray | Improvement in attachment to boring-brace | braces |
| 90,207 | May 18, 1869 | A. Thompson | Improvement in saw-filing machines | saw sharpening machines |
| 91,635 | Jun. 22, 1869 | T. Holt | Improvement in grooving-machine | dado machines |
| 92,927 | Jul. 27, 1869 | A. Amory | Improvement in guide-attachments for boring-instruments | drill accessories |
| 94,316 | Aug. 31, 1869 | C.L. Inslee, W.H. Inslee | Improvement in steam-engine valve-gear | valve gear |
| 95,060 | Sep. 21, 1869 | J. Winkelhouse | Improvement in bit-holder | brace chucks |
| 95,868 | Oct. 19, 1869 | J.F. Allen | Improvement in steam-engine slide-valves | steam engine valves |
| 97,090 | Nov. 23, 1869 | W.H. Howland | Improvement in knife-sharpener | sharpening apparatus |
