Patent GB-191112160-A (GB)
Title: Improvements in or relating to Speedometers.
Inventor: LEMAIGNEN ROBERT BERTIN AUGUST
IPC: G01P3/10
Filed: 1911-05-19
Granted: 1912-03-21
Abstract: 12,160. Lemaignen, R. B. A. May 19, 1910, [Convention date]. Periodic-counter speed indicators.-The counting-mechanism described in Specifications 7307/10 and 7308/10, [both in Class 106 (i), Calculating &c.], is combined with clock-work and provided with variable gearing to allow the instrument to be used for high and low speeds. Means are also provided whereby the clock is rewound by the device used for zeroizing the counter. The counter is operated by a cam 12<1>, Fig. 8, on the driven shaft 13 and a lever 8<1> secured to a shaft 8 bearing the actuating pawls. While the device is inoperative, t h e lever 8<1> is held out of gear by a pin 21 thereon engaging the end 19<3>, Fig. 9, of a spring- controlled lever 19<1> provided with an exterior push - piece 19<0>, by means of which it may be rocked. The lower end of the lever 19<1> is provided with a tail-piece 19<2> and a pin 19<4> adapted to engage, under the influence of a spring 20, with a notch 14<1> in the spring barrel or with a tongue 14<2> carried thereby. On forcing in the knob 19<0>, the barrel is free to revolve, and the lever 8<1> falls into gear with the cam 12<1> and the counter is actuated until the projection 19<2> falls into the notch in the barrel and stops the clock, as shown in Fig. 11. The end 19<3> of the lever moves under the pin 21 when the lever 8<1> reaches the highest point of its path. Means are provided to prevent the clock from being thrown out of gear without the counting - mechanism having been first zeroized by the rotation of the shaft 11. On the spindle 8 is mounted a lever 28<1>, Figs. 9 and 11, which is provided with pins 28<2>, 28<3> and is drawn towards the shaft 11 by a spring 29 connecting it to a lever 30<1> pivoted at 30. The pin 28<2> is adapted to engage a notch 19<5> formed at the end of the lever 19<1>. The lever 30<1> is formed with a terminal face 30<2> and a notch 30<3> which are adapted to receive the pin 28<2>. The lever also carries a pin 30<4> which engages the extension 19<3>. The zeroizing- spindle 11 is provided with a cam 31, adapted to engage the pin 28<3>, and also with a pin 32 adapted to engage with a face 30<6> of the lever 30<1>, which is recessed at 30<5> to allow movement of the pin 32. When in position for using the device, the pin 21 is held out of range of the driving-cam by the extension 19<3> of the lever 19<1>, as shown in Fig. 11, and the lever 30<1> is so placed as to prevent the movement of the pin 32 and thus the shaft 11. On depressing the push 19<0>, as shown in Fig. 9, the pin 21 and the lever 8<1> are released, and the lever 30<1> is moved, through the pin 30<4> striking the part 19<3>, to free the pin 28<2> and allow the lever 28<1> and the pin 28<2> to come into the path of the notch 19<5>. The face 30<6> releases the pin 32 and no longer prevents the rotation of the zeroizing-shaft 11. The pin 28<2> of the lever 28', released by the notch 19<5>, rests in the notch 30<3> of the lever 30' and prevents the movement of the lever 19<1>. The rotation of the zeroizing-shaft 11 raises the lever 28<1>, by means of the cam 30 and the pin 28<3>, to its original position, and the clock is rewound through gear wheels 27, 26. Transmission mechanism.-The variable gearing for use in measuring high and low speeds is carried by a frame 22<1> pivoted at 22 and formed of plates connected by shafts 23, 24, on which are mounted pinions 23<1>, 23<2> and 24<1>, 24<2>, respectively. The cam 12<1> is not mounted directly on the shaft 13, but on a loose sleeve 12, Fig. 5, provided with pinions 12<2>, 12<3>. Rocking of the frame from the exterior is effected by a knob 22<0>, and the gearing 13<1>, 23', 23<2>, 12<2> is arranged to give an increased speed to the driving cam, while the arrangement 13<2>, 24<1>, 24<2>, 12<3>, gives a decreased speed, the pinions 13'. 13<2> being mounted on the shaft 13.