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Uses of Storage Batteries—Internal Combustion Engine Ignition-Auto
mobile Starting and Lighting Systems—Shifting Gears by Electricity -Electric Pleasure and Commercial Automobiles—Isolated Lighting Plants — Train Lighting — Storage-Battery Locomotives — BatteryDriven Street Cars–Submarine Boats-Miscellaneous Marine Applications—Railway Switch and Signal Service-Stand-by and Booster Service Drawbridge Operation-Mine Lamp Battery.
Uses of Storage Batteries.-In this chapter the writer intends to describe briefly the most interesting of the many possible applications of storage batteries, some of which are unusual, to say the least. A rather flexible imagination is needed to consider that the cheerfully lighted farm home; the lifting of a massive drawbridge; the roaring start of a powerful automobile or hydroaeroplane engine and the noiseless movement of the electric automobile are all accomplished by the same agency. Storage batteries propel numerous electric launches on the water's surface, and are the sole power for the submarine lurking in its depths. Hundreds of palatial yachts are illuminated by this means, and the penetrating shaft of light from the miner's lamp is produced by the same energizing source. A wireless call for help from a ship in distress, with its life-saving possibilities, is produced from a few cells of a storage battery. The headlights of the myriad automobiles now using our highways after nightfall attest to the practical value of this current-producer.
The magnitude of the industry and the great possibilities of the field for storage batteries can be only briefly touched upon, but it is evident, from a perusal of the following list, that they can be used anywhere a dependable source of current is required. We find storage batteries used in: Central lighting and power stations; electric railway power houses ; municipal and office building lighting and power; steel mills; electric hoist and elevators;
isolated lighting plants for hotels; suburban residences and farms; railway switch and signal service; railway car lighting; interlocking switch service; United States Government submarine and gunfiring service; telephone, telegraph, wireless and fire-alarm service; laboratory and school work; electroplating; automobile enginestarting; gas-engine ignition; automobile lighting; electric trucks and pleasure cars; street railway cars; electric launches and mine and industrial locomotives.
The Storage Battery for Gasoline-Engine Ignition.—Because of the almost universal employment of electricity for lighting and starting ystems, the battery ignition system has been improved materially, inasmuch as the storage battery supplying the current is constantly charged by a generator. A number of systems have been devised, these operating on two different principles, the open circuit and the closed circuit. An example of the closed-circuit system is shown at Fig. 54, and is of Connecticut design, the complete ignition system consisting of a combined timer and hightension distributor, a separate induction coil and a switch. The system is distinctive in that the timer is so constructed that the primary circuit of the coil is permitted to become thoroughly saturated with electricity before the points separate, with a result that a spark of maximum intensity is produced. The action is very much the same as that of a magneto on account of the saturation of the winding. Another feature is the incorporation with the switch of a thermostatically operated electro-magnetic device, which automatically breaks the connection between the battery and the coil should the switch be left on with the motor idle.
The contact-breaker mechanism consists of an arm A carrying one contact, a stationary block B carrying the other contact, a fiber roller R, which is carried by the arm A, and operated by points on the cam C, which is mounted on the driving-shaft. Normally, the contacts are held together under the action of a light spring. As the four cams, which in touching the roller R raise the arm and separate the contacts, are 90 degrees for a fourcylinder motor, the period of saturation of the coil or the length of time the current flows through it to the battery is sufficiently long so that when the points have separated, the current, which
has “piled” up, induces an intensely hot spark at the plugs. This is an advantage, inasmuch as it insures prompt starting and regular ignition at low engine speed, as well as providing positive ignition at high engine speed.
The thermostatic circuit-breaking mechanism is very simple. This consists of the thermostat T, which heats when the current passes through it for from thirty seconds to four minutes without interruption, and thus is bent downward, making contact with the contact L. This completes an electrical circuit, which energizes the magnets M, causing the arm K to operate like the clapper in an electric bell. This arm strikes against the plate, which releases whichever of the two buttons in the switch may be depressed.
As will be observed, the transformer coil provided has five terminals. One of these is connected directly with the ground, the other leads to the central secondary distributing brush of the timer-distributor. Of the three primary leads, one goes to the switch, one to the wire leading from the storage battery to the timer, and one directly to a terminal on the timer. The switch is provided with three buttons, the one marked B being depressed to start the engine, as the ignition current is then drawn from the storage battery. After the engine has been started the button marked M is pressed in, this taking the current directly from the generator. To interrupt ignition the button "off” is pressed in, this releasing whichever of the buttons, B or M, is depressed. Four wires run from the distributor section of the igniter to the spark plug
One of the most popular of the combined starting, lighting and ignition systems is the Delco, which is shown at Fig. 55. For the present we will concern ourselves merely with discussing the ignition functions of the system, leaving the self-starting and electric-lighting features for consideration later. Current is produced by a one-unit type motor-generator, although the windings of the device when operated as a motor or a generator are entirely separate. The ignition current is obtained either from a storage battery, which is kept in a state of charge by the generator, or from a set of dry cells which are carried for reserve ignition. The ignition system consists of a one-unit non-vibrator coil,