GB197730A - Improvements in or relating to machines for testing resistance to wear, lubricating properties, and the like - Google Patents

Abstract

197,730. Spindel, M. Feb. 15, 1922. Testing physical qualities of materials; testing and measuring lubricating efficiency of liquids.- In a machine for testing the resistance to wear and machining of materials, the quality of tools, the lubricating properties of oils, &c., one of the two test pieces acting on one another is rotated and the other N is mounted on an independently supported frame H which is rotatable about the axis of rotation of the rotary piece F, the longitudinal force transmitted from the piece F to the frame H being measured by a dynamometer T. The machine may be self-contained, or the shaft carrying the frame H may be mounted between the centres or on the saddle cf a lathe and the piece F on the lathe spindle. The, test piece N is carried by a lever L<2> pivoted on an adjustable slide, J, pressure being exerted by a weight or a screw 7. The wear of the two pieces N, F is measured by the displacement of the lever L<2>, and the wear on the one piece F by the displacement of a lever 0<2> pivoted on the slide, J, the movements of the levers being recorded on a drum 25. The distance from the pivot K to the points of contact Q, R is maintained substantially the same throughout the test by adjusting the slide J. The frame H may be balanced by means of a pendulum 9 having an adjustable weight 10. Instead of hanging a weight directly on the lever L<2>, the free end of the, lever may be connected to a chain 3 running over pulleys 1, .2 and carrying movable weights 6 on both sides. The lever is first balanced by means of the weights and then the load is applied by shifting weights from one side to the other, without affecting the equilibrium of the frame H. The movement of the dynamometer T may be recorded on a drum 24 driven by the gearing shown. The drum 25 for recording the movements of the levers L<2>, O<2> is mounted on the frame H and driven through shafts 22, 23 geared together by a chain or cord passing round pulleys 17 in the plane of the axis of rotation of the frame H. The test pieces are roughened and cleaned before testing and the piece F is rotated so slowly that the rubbing surfaces never become smooth. During a grinding test the grinding disc F grinds into the flat test piece N and the specific grinding pressure decreases, the resistance to wear being ascertained by registering the lineal distance that the disc has passed over the flat test piece, the depth, length, and width of the cut made, and the work performed for each depth. Lubricating oils may be tested by being fed between the rotary disc and the flat test piece until there is no further noticeable grinding action. Bearings and lubricants may be tested by mounting the bearing on the lever L<2> and the corresponding shaft in the place of the test piece. F. The frame H may be moved laterally during a test by screw-and-nut gearing.