A New or Improved Automatic and Autographic Testing Machine, chiefly for use in Testing the Cutting Efficiency of Tool Steel.

摘要

26,321. Herbert, E. G., and Fletcher. C. Dec. 5. Lathes; drilling.-In apparatus for testing the cutting efficiency and durability of tool steel, and the relative value of various cutting compounds or lubricants, or for determining the power absorbed by the tool and its efficiency with various cutting- angles and under different cutting-speeds, the tool 29, Fig. 1, is mounted upon a pivoted carriage 27, resembling a steelyard, and is applied to the lower edge of a rotating vertical standard test tube 22 ; the cross-section of the cut is thus kept constant. The carriage, Fig. 5, is provided with knife-edges 30 in an horizontal plane, and the balance beam 35, 33 is controlled by an adjustable counterpoise 36 and dash-pot 37, 38 on one side, and on the other side by weights 91 and an adjustable weight 34, which, by means of a scale 39, facilitates adjustment of the upward pressure applied to the tool 29 in order to maintain the cut. The tool is provided with a screw 29a and with means 77, 78, Fig. 7, for enabling it to be set horizontally. The tube 22 is fed vertically downwards against a fixed supporting- plate 40, which, however, allows room for the tool to act, by means of weights 13, Fig. 1, upon the spindle 9. The length of tube cut away before the tool becomes blunted is graphically recorded, as shown in Fig. 15, against the number of revolutions of the tube by device 42, 41, Fig. 1. In testing lubricants, a tank 87, pump 88, and supply and return pipes 89, 90 are provided to force the lubricant into the test tube and on to the tool. An arrangement 71, 72, 75a, Fig. 19, is provided for measuring the force required to balance the reactive turning-effort of the tube upon the tool. The tool may be set to take a cut of definite extent, instead of being merely pressed against the tube with a definite pressure, by means of a screw 80, Fig. 11, engaging with an extension 81 upon the end of the balance beam 27, and may also be set so as to be out of action, when a predetermined amount of wear has taken place, by means of a micrometer screw 82. The tube 22 can be driven at various speeds by means of friction wheels 7, 8, the adjustment to a required speed being facilitated by the aid of a speed-indicating arrangement consisting of a mechanicallyoperated bell-hammer and of an adjustable pendulum. A rack traversing- motion 15, 16, 20 for moving the tube vertically is provided. Various modifications are described dealing with the provision of a drill for forming the test-tube from a solid rod as the test proceeds, and with arrangements in which the tool is rotated while the test-tube is held stationary.