Electrical Equipment of Automobiles.
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The second meeting of the Institution of Automobile Engineers for the current session was held on Wednesday, the 8th inst., when a, paper by Ar. A. Ludlow Clayden member of the Society of Automobile Engineers Of America, entitled "The Electrical Equipment of a Car," was read by Mr. F. S. Bennett, the British agent for Cadillac cars.
The paper was devoted entirely to the consideration of starting and lighting outfits. The author pointed out that besides the Delco system, which is of a special nature having particular advantages and which can only be made under licence from that company, there are two main systems. In one of these a single unit serves with the help of a battery, of course, both to generate a current for starting and lighting and also as a motor to revolve the engine. In the other and more popular system, two units are employed, a separate generator and a starting motor.
The second system has proved in the light of American experience to be the more satisfactory one. This, he stated, is principally due to the fact that with the single unit driven at the most at three times the engine speed-, a heavy armature is necessary if it is Lo be used as a motor. The inertia of this armature having to be overcome when the engine is rapidly accelerated or decelerated, necessitates heavy driving gears.
Various systems of dynamo control were discussed, and the author stated that the situation in regard to these in America is indefinite.
The weakest point in the electrical equipment of an automobile is undoubtedly the accumulator.
Turning to the general question of ignition, starting and lighting, the author went on to say "Judging by articles and correspondence in the Press. the British industry. is not yet convinced that the days of magneto ignition for motorcars are numbered. Certainly to return to battery ignition does at present seem to be a retrogression. The principal reason why American manufacturers have adopted battery ignition again to so large an extent is admittedly that having the dynamo and accumulator, battery ignition becomes cheaper than magneto ignition. Obviously if the dynamo can be depended upon to furnish enough current of the same reliability as the magneto, there is no object in carrying the additional weight of a separate electrical machine." It is.to be regretted that the author in his paper has evidently entirely omitted to consider the commercial chassis. There is no doubt that in considering the matter from this point of view, an entirely different set of conditions is to be met. It is unlikely that for some time to come self-starting will be a common feature of heavy vehicles. Not only is the demand for luxury and ease absent from this side of the industry, but it is fairly obvious that the difficulties which have been encountered in connection with starting and lighting sets, such as power required to start large engines when cold, depreciation of the battery charge in oases where a fair number of stops per day are made and where the straightaway running of the engine, in between stops is not sufficient to recharge the batteries with the resultant failure of these owing to heavy discharging and failure to recharge, will be accentuated. Moreover, the consequence of failure is more far-reaching. The discussion was opened byalr: Woods of the British Westinghouse Electric and Manufacturing Co, Ltd. He suggested that the difficulty in connection with single-unit systems would not be so great in this country where the use or small and therefore more easily started engines is prevalent. Mr. Berryman, of the Daimler Co., in relating some experiences of his, reminded us that increased manipulation of the spark-advance lever. becomes essential when a return to battery and coil ignition is made, thus rendering driving more a matter of skill instead of less, which must be the trend.
Mr. A. A. Remington, of Wolseleys, also contributed to the discussion. He raised doubts as to the superiority of the two-unit system.
An interesting and lively participation was on the part of a, Mr. Martin, an electrical engineer, who had, as he stated, attended the meeting out of curiosity. He related his own experience of electric starting and lighting, which occurred 14 years ago on an old Panhard in the wilds of Ireland. He stated that lie and a friend built a satisfactory starting and lighting set, and, moreover, he claimed that the car itself, the engine, and gearbox fell to pieces while his start. ing and lighting set was still in a good state of repair.
Mr. Bennett replied on behalf of the author to the points raised and the meeting was closed in the usual manner.
The next will take place on the 13th prox., when Mr. Lanchester will read a Paper on worm gears. B35