GB107591A - Improvements in or relating to Speedometers. - Google Patents

Abstract

107,591. Soulat, J. Oct. 30, 1915, [Convention date]. Periodic-counter speed indicators. - Motion is communicated from a shaft f through toothed gearing to two spring-barrels c, b containing friction springs, on the arbor of the second of which is secured an escape wheel b<0> governed by a balance b<5>. Also secured to the arbor b<1> are two ratchet wheels b<2>, b<3> engaged by spring-controlled levers d<2>, d<3>, the teeth of the wheels being so spaced that one and a half seconds elapse during the progress of a lever along a tooth. The levers either differ in length sufficiently, or the wheels are so arranged with regard to one another that the times of the fall of the levers from the teeth of the wheels b<2>, b<3> differ by half a second. Secured to the arbor c' of the barrel c are arms c <1>, c<2> which form a four point star and are arranged in the planes of the levers d<2>, d<3>. Also mounted on the arbor c<1> are cams c<4>, c<5> which control spring-depressed levers e<4>, e<5>, pivoted at e, and pawl-levers i<40>, i<50>. Mounted in the levers e<4>, e<5> are the shafts of pairs of wheels h<1>, h<2>; h<3>, h<4>, the wheels h<1>, h<3> being driven from the shaft f and the wheels h<2>, h<4> being provided with ratchet teeth to engage similarly toothed wheels j<1>, j<2> driving the indicating hand. The arrangement of the cams c<1>, c<5> with regard to the other timeoperated parts is such that the wheels j<1>, j<2> are alternately driven for one second, then held by the pawls i<40>, i<50> for a second and a half, during which time the levers e<4>, e<5> carrying the driving-wheels have been raised to the disengaged position, and finally released by the pawls and returned during half a second towards the starting point by spiral springs attached to wheels j<10>, j<20> secured to the wheels j<1>, j<2>. Pins j<100>, j<200> serve as zero stops, and pins j<1000> and j<2000> on the wheels j<1>, j<2> are adapted to engage pins m<1> on a disk m secured to the shaft of the indicating-hand. Braking- fans n may be driven by the wheels j<1>, j<2>. Means for stopping the clockwork when the device is idle comprise a three-armed lever p, one arm p<4> of which bears a spring p<40> adapted to engage the balance b<5> when an arm of the lever p has fallen into a notch m<0> in the disk m at the zero point and a third arm p' has fallen into one of a series of notches in a disk b<10> on the arbor b<1>, such notches being arranged so that one of the ratchet wheels h<2>, h<4> is always in engagement with one of the wheels j<1>, j<2> when the arm p<3> has fallen into a notch.