| All Patents in class 451/418 |
Patents 1 -
10
of 13
      |
| Picture | Number | Date | Patentee | Title |
| | 459,572 | Sep. 15, 1891 | A.K. Bonta | Commutator Turning Device |
| | 586,514 | Jul. 13, 1897 | P.B. Bosworth | Commutator Truing Device |
| | 632,666 | Sep. 05, 1899 | F. Wilkie | Commutator Grinding Rig |
| | 635,346 | Oct. 24, 1899 | R.S. Papprill | Tool for Abrasive Purposes |
| | 651,342 | Jun. 12, 1900 | E.D. Carr | Commutator-Truing Device |
 | 660,618 | Oct. 30, 1900 | P.B. Bosworth | Device for truing commutators |
| | 723,399 | Mar. 24, 1903 | J.B. MacIntosh | Device for Filing Commutators for Dynamos or Motors |
| | 803,657 | Nov. 07, 1905 | O. Zschockelt | Collector-Polisher |
| | 945,784 | Jan. 11, 1910 | O.E. Hunt | Commutator Truing Machine |
| | 971,753 | Oct. 04, 1910 | O.E. Hunt | Commutator Truing Machine |
