GB190304444A - Improvements relating to Dynamometers - Google Patents

Abstract

4444. Weston, E., and Benecke, A. O. Feb. 25. Dynamometers for power-driven machines are adapted to make continuous time records of the power supplied. The driving-pulley y transmits the power to be measured to the shaft m through a strong coiled spring o. An arm h is integral with a metallic sleeve h<2> secured to the shaft m, and the arm carries a brush h<1> adapted to bear on a resistance r connected at its ends to rings t, t<1>, on which bear brushes j, j<1> connected through an adjustable resistance q with the battery l. A third brush j<2> makes contact with the sleeve h<2> and arm h. A certain fraction of the battery pressure is taken from the resistance r through the brushes j<1>, j<2> and wires w<3>, this fraction depending on the relative position of the arm h and pulley y, i.e., on the torque transmitted. The current in the wires w<3> passes through the moving coil c of a measuring- instrument, of which i is the index needle. A movement of the index needle closes the contact p<1>, s' or p<2>, s<2> according to its direction, thus sending current from the split battery b in one or other direction through the wires w to the motor a. The worm gear g and arms a<1>, a<2> are turned by the motor until the index needle is again free, the number of revolutions of the motor being thus proportional to the deviation of the index needle, i.e., to the torque in the shaft m. An arm n with a recording-stylus makes a continuous record of the torque or power on a clock-driven cylinder e.