GB698868A - Improvements in or relating to devices responsive to predetermined ratios of speed and arranged to operate indicating mechanism or control gear - Google Patents

Abstract

698,868. Differential switches. METROPOLITAN RAILCARS (GANZ PATENT), Ltd., and LEHEL, V. Dec. 18, 1950 (Sept. 24, 1949], No. 15027/49. Class 38 (v) [Also in Groups XIX and XXIV] A balk device responsive to changes in the relative speed of two rotating shafts, e.g. 5, 6, Fig. 1, comprises two or more friction clutches which release balk members in successive stages as predetermined speed ratios obtain between the shafts, permitting stepwise movement of a control number 3, which movement may merely indicate when a predetermined speed-ratio condition exists ; may be used as a safety speed governor where the shaft 5 is driven by a synchronous motor, or as part of a switch gear controlling paralleled alternators; or to control engagement of gears or dog-clutches in a vehicle change-speed gear. Fig. 1, which is explanatory only, has a single balk member 1 with limited circumferential freedom on splines 20, Fig. 3, associated with a gear wheel 8, driven by the shaft 6, and comprising one element of a cone or multi-plate friction clutch, the complementary element of which is a bevel 9 geared to the shaft 5. Relative rotation in the direction of the arrow 14 turns the balk-member 1 to one limit position, in which the apertures 23 therein are out of register with axial keys 21 on the control member 3 which latter is thereby prevented from axial movement, and pressure thereon engages the friction clutch. Relative rotation in the opposite sense turns the balk-member 1 to its other limit position in which its apertures 23 permit axial passage of the keys 21, thus allowing movement of the control member 3. The multi-stage balk devices are described only in relation to controlling engagement of gears and dog-clutches in a vehicle charge-speed gear (see Group XXIV).