| Patents for none listed |
Patents 1171 -
1185
of 3266
      |
| Number | Date | Patentee | Title | Type |
| DE-518,155 | Feb. 13, 1931 | n. listed | Machine for Grinding Balls by Means of Two Cylindrical Grinding or Guide Discs | cylindrical grinders |
| FR-699,351 | Feb. 13, 1931 | n. listed | Improvements to Grinding Machines | grinding machines |
| FR-699,483 | Feb. 16, 1931 | n. listed | Improvements to Grinding or Grinding Machines | grinding machines |
| 1,793,112 | Feb. 17, 1931 | F. McMahon | Angle Plate | angle bars and angle plates |
| 1,793,714 | Feb. 24, 1931 | E. Newberg | Duplex Wrench | nut wrenches |
| 1,794,340 | Feb. 24, 1931 | M.K. Parkhurst | Optical Measuring Device | measurement gauges |
| 1,794,361 | Mar. 03, 1931 | L.F. Nenninger, B.P. Graves, E.J. Kearney, J.B. Armitage | Milling-Machine Spindle and Tool | milling machine tools |
| 1,797,121 | Mar. 17, 1931 | F.J. Bohn | Micrometer Gage for Internal Threads | micrometers |
| 1,797,122 | Mar. 17, 1931 | F.J. Bohn | Micrometer Gauge for Internal Threads | thread gages |
| GB-345,092 | Mar. 19, 1931 | n. listed | Improvements in or Relating to Grinding or Abrading Machines | grinding machines |
| 1,797,730 | Mar. 24, 1931 | E.M. Pfauser | Socket Attachment for Tools | socket wrenches |
| 1,798,194 | Mar. 31, 1931 | J.H. Dodge | Reversible Ratchet Wrench | ratchet wrenches |
| 1,798,481 | Mar. 31, 1931 | N.F. McNaught, E.H. Peterson | Ratchet lever | ratchet wrenches |
| 1,798,482 | Mar. 31, 1931 | N.F. McNaught, E.H. Peterson | Ratchet lever | |
| 1,798,496 | Mar. 31, 1931 | J. Reid | Lubricating Eccentric Driving Gears | internal combustion engine lubrication |
