The gasoline automobile is an excellent example of a self-contained means of transportation. Its essential parts are the chassis, comprising the frame with running and steering gears; the motor, an internal combustion gasoline engine; the transmission system, by means of which the energy developed in the engine is applied to the wheels as work; the ignition and lighting systems; and the lubrication and cooling systems.
Since the frame of an automobile is subjected to severe strains, manufacturers use for this purpose an alloy of steel that has been given its maximum tensile strength by means of a heat treatment.
Since the frame of an automobile is subjected to severe strains, manufacturers use for this purpose an alloy of steel that has been given its maximum tensile strength by means of a heat treatment The engines are of many forms, varying in the number of cylinders. The operation of the piston in a four-stroke engine is shown in Fig. 267. The gasoline and air are mixed in proper proportions in the carburetor, and ignition in the cylinders is produced by electric sparks.
The transmission system includes the speed-shifting gears and the shafts and gears required for changing the reciprocating movement of the pistons of the engine into the rotation of the rear wheels of the chassis.
Cooling systems are of various kinds, some employing a draft of air forced past the radiator, others a forced current of water, and still others a water circulation which depends upon the difference between the specific gravity of cold and of hot water.
A cross section of the engine, transmission, etc., of a much-used type of car is shown in detail in Fig. 1, Figure 2 shows details of the mechanism of the rear axle and its accessories. One form of carburetor is shown in Fig. 3.
FIG. 1. -Automobile Engine and Transmission
FIG. 3. - Carburetor
