| All Patents in class 408/192 |
Patents 1 -
14
of 14
      |
| Number | Date | Patentee | Title | Type |
| 52,174 | Jan. 23, 1866 | A. Parsons, C.F. Kimball | Improvement in Bits for Boring Holes | countersinks |
| 62,849 | Mar. 12, 1867 | T. Hofstatter | Improvement in Augers | countersinks |
| 63,392 | Apr. 02, 1867 | M. Jincks | Improvement in Boring Bits | countersinks |
| 80,915 | Aug. 11, 1868 | L. Colt | Auger | drill depth stops |
| 137,373 | Apr. 01, 1873 | F. Jonas | Adjustable Countersink Bit-Assembly | countersinks |
| 178,448 | Jun. 06, 1876 | W.H. Laughlin | Improvement in Countersinks | countersinks |
| 256,979 | Apr. 25, 1882 | J.W. Cooper | Washer Cutter and Adjustable Bit | washer cutters |
| 326,342 | Sep. 15, 1885 | J.C. Smith | Adjustable Concentric Channeler | adjustable drill bits |
| 327,641 | Oct. 06, 1885 | G.W. Abbott, G.S. Forrest | Countersink | countersinks |
| 458,091 | Aug. 18, 1891 | C. Beauchene | Expansion-Bit | adjustable drill bits |
| 488,701 | Dec. 27, 1892 | T.O. Smith | Brace, bit attachment | |
| 727,580 | May 12, 1903 | G.W. Brackin | Countersink | countersinks |
| 860,488 | Jul. 16, 1907 | A. Koontz | Boring-Tool | countersinks |
| 1,398,779 | Nov. 29, 1921 | L.S. Hayden | Tool for boring and counterboring wood | drill bits |
