| All Patents in class 451/347 |
Patents 1 -
9
of 9
      |
| Number | Date | Patentee | Title | Type |
| 1,987,837 | Jan. 15, 1935 | A.W. Mall | Portable grinding machine | |
| 2,081,360 | May 25, 1937 | A.W. Mall | Rail slotter | |
| 2,106,034 | Jan. 18, 1938 | A.W. Mall | Rail grinder | |
| 2,116,491 | May 03, 1938 | A.W. Mall | Angle grinding spindle | |
| 2,148,766 | Feb. 28, 1939 | A.W. Mall | Track grinding machine | |
| 2,214,141 | Sep. 10, 1940 | A.W. Mall | Rail slotter | |
| 2,223,732 | Dec. 03, 1940 | A.W. Mall | All purpose grinding apparatus | |
| 3,509,667 | May 05, 1970 | K.L. Lindmark | Method of grinding welded rail | track maintenance machinery |
| 3,566,546 | Mar. 02, 1971 | K.L. Lindmark | Apparatus for grinding welded rail | track maintenance machinery |
