Gear-Changing Simplified

Sun (Auckland), Volume II, Issue 516, 20 November 1928, Page 7

Gear-Changing Simplified

New English Automatic Device AFTER five years of secret experimental work a British firm has evolved a method of automatic gear change which has proved successful in a test covering 50.000 miles, says the overseas “Daily Mail.” The firm is Armstrong Siddeley and the new system of control is to be installed on the 20 and 30 h.p. models.

There is no gear lever. The gear positions are clearly marked on a quadrant on the steering wheel, as in the case at present on most cars with the ignition retard and advance. The lettering is: Reverse, Neutral, Low, Medium, Normal, High. There is a pedal in the place of the normal clutch pedal. When you wish to start, says the article, you place a pointer on the quadrant opposite Low, which corresponds to the ordinary motor-car’s bottom gear. You then depress the pedal, and the car starts off smoothly and without fuss. HOW IT IS DONE To speed up, you place the pointer on the quadrant opposite Medium, which corresponds with the second gear of an ordinary motor-car. Depress the pedal again, and the automatic gear change comes into operation. So for Normal and for Fast speed, which correspond to the top gear of the ordinary car. The automatic gear changing device does not come into operation until you actually depress the pedal. Thus you can elect your next gear in advance. Let us suppose that you are in top gear—high on the quadrant—and are approaching a hill. It is obvious that you will require a lower gear when the engine begins to lose its speed. So you put the pointer on the quadrant opposite Normal. As soon as the engine shows the least sign of laboring you press the pedal, and the car changes down into Normal or third gear. The same applies in" traffic If you are in top gear it is obvious that the next change will be down. So you put your pointer opposite Normal, and when a check occurs you press the pedal and at once a change into the lower gear is effected. YOU CAN’T HEAR IT Another feature of the self-changing gear box is its silence. Except for the variation of engine note, due to its change of speed, it is impossible for tl\e driver, without reference to the lettering on the quadrant, to know in which gear the car is running. Silence on all gears is obtained by using a gear of the always-in-mesh type in place of the sliding gear. The automatic change mechanism consists of a mechanical finger. When you move the pointer on the quadrant opposite the gear into which you desire

to change, you move the mechanical linger into a position to effect the change. When you press the pedal the mechanical finger does its work. In the course of a te«t in which the “Daily Mail’s” motoring correspondent said the automatic proved itself to be fool-proof, as many as 15 gear changes

were made in ten seconds. The fact that no time is lost in changing speed means greatly increased acceleration. A comparative test with two cars with engines of equal power, of the same weight, and driven by the same driver up to a speed of 40 m.p.h. from a standing start, gave th-e following results: The car with the self-changing gear gained eleven seconds, or 33 per cent., on the car with the ordinary gear. In 25 seconds from a standing start the car with the self-changing gear gained 450 feet, or GO per cent. DRIVERS’ QUESTIONNAIRE It is the fashion to formulate questionnaires. An English motorist has invited replies to the following: (1) Do you consider it politically unconstitutional for a crankshaft to have continual revolutions? (2) Do you believe that some sparking plugs lead double lives? (3) Do you believe that police stopwatches are inspired? (4) If you cannot afford a car, what can you afford ? (5) If you saw a taxi-man pull into his left, and wave you on, would you be able to withstand the shock? (6) Are you in favour of a speed limit for speedometers?