GB436107A - Control devices for variable speed gears - Google Patents

Abstract

436,107. Variable speed gearing. FLEISCHEL, G., BlÚneau, Yonne, France. July 13, 1934, No. 20593. [Class 80 (ii)] Relates to an engine-driven change-speed gear, the gear ratios of which are altered by a power-operated device controlled by a throttlepedal, or other member regulating the engine output. According to the invention, the power-operated device is controlled by two devices, 18d, 18m, of which one, 18d, is arranged to bring into action a lower gear, and the other, 18m, is arranged to bring into action a higher gear, the control member acting on one of the said devices at or near one of its extreme positions to produce a change in the gear ratio. The control device may also include automatic means, operated, e.g. by the speed of the driving shaft, for neutralizing or correcting, or for warning the driver of, an incorrect action he has made. Gear changing is effected by a cam-shaft 7 capable of being operated by a servo-motor, e.g. electric motor 8, or by an engine shaft. The motor 8 is rotated in one direction to step-up the gear, or in the other direction to reduce the gear according as to whether it is energized through terminals 9d or 9m. The latter are connected to an electric source 10 through switches 18d, 18m, respectively. The accelerator pedal 13 which is pivoted at 15, has a finger 17 which closes the switch 18m when the pedal is held raised by a spring 131. A switch 19 which is open when the engine clutch is disengaged prevents actuation of the motor 8. Depression of the throttle and brake pedals 13, 20 opens the switch 18<m> and closes switch 19, and a pusher 22 on the pedal 13 engages a spring blade 21 on a pivoted lever 16 to move a rod 14 and open the engine throttle. When the latter is fully open, further movement of the pedal 13 flexes the blade 21 and the finger 17 closes the switch 18d and causes a change to lower gear. If the car is insufficiently loaded the pedal 13 is released so that the finger closes switch 18m and produces a change to a higher gear. The switches 18d, 18<m> may be arranged so that the gear changes occur at intermediate positions of the pedal 13. Automatic means controlled by the engine may also be combined with the invention whereby the speed ratio is varied when necessary or whereby the driver is prevented from changing to an incorrect gear. As shown, a centrifugal governor 23 can move axially a rod 24 supporting a pivoted lever 25, the ends 251, 25<2> of which are connected to the electric source 10. Stationary contacts 26d, 27m are connected to terminals 9d, 9m, and contacts 26m, 27d are in series with switches 18m, 18<d> respectively. The lever 25 is acted upon by springs 28', 28<2>, the latter being stronger than the former. When the engine speed is low the contacts 26d, 27d are made and servo-motor 8 is energized to change to lower gear, and the driver cannot change to higher gear. At a greater engine speed spring 28<1> is overcome, contacts 26<m>, 27d are closed. The automatic action is then stopped and the driver can increase or decrease the gear ratio. At a still higher engine speed the spring 28<2> is overcome, contacts 26m, 27<m> are closed and a change to higher gear occurs, a change by the driver to lower gear being impossible. The springs 28<1>, 28<2> may be replaced by an equivalent single spring. If the variable-speed gear is of the step-by-step type and V<1>, V<2> are the high and low engine speeds it is necessary that the contacts 26d, 27m, 26<m>, 27d are closed when the engine speed equals V<2>, equals V<1>, is greater than V is greater than V<2>, respectively. For this purpose the lever 25 has ribs 29<1>, 29<2> engaging rollers 30', 30<2> on pivoted levers 31<1>, 31<2> acted upon by springs 32<1>, 32<2> of different strengths. The circuit between switch 18m and 9m and between switch 18d and 9d may include switches operable by the driver so that he can retain any gear ratio in action. The contacts 27m and 26d instead of being connected to 9m, 9d may be connected to an apparatus to warn the driver that he has forgotten to perform some necessary action. Alternatively, the apparatus may be arranged so that sometimes the driver is warned and sometimes the gears are changed automatically.