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Show II 1 THE MODERN AUTOMOBILE By George Bergstroni, Instructor Auto-Meajianics, Ugden lligh School. Written especially for The Standard Examiner. IBRAK i S at Brakes arc considered one of the Jt most Important parts or units of ihel V car. Not only is It necessary at limes I !o stop quickly, but through the med-'l jH mm of tho brakes Is the car controlled I lU on grades or in traffic wherever Dei ;j;3 essary. It Is essential that the brak B y- be in perfect uorklny order at nil jtj times, which menns thai the llnlnp of HI tonae non-burning material Is In good jrl condition and that tfic. brake rode, HI pins, and arms aro kept well lubrl- BJi rated and properly adjusted. Tli.- f"r- n ward motion ot the car with its 18 weight of three or four thousand Mi pounds or more, causes considerable E Inertia which can be controlled i the motor to some extent. This In j done by shutting off the gas and Sf spark, leaving the clutch in. The or- ai dinary motor ha a compression W from 50 to 70 pounds per square Inch ill which is utilized by this method. This gin is using the engine for a brake and Wl the thoughtful driver will take ad van - wl 'age of this method of Snubbing th Sz forward movement as much as pa Si slble as it saves the other Wr.ikes. an helps to keep them In perfect worl Ing condition. CLASSIFIt lin : Brakes are divided and classified jju usually by their location, i. e., ex- Jj ternal or contracting. Internal or ex- 4j pending. The two classes can fur- WJ iher be divided according to the waj j they operate, the scissor action, cam, 'M'r and toggle. The brakes are usually It placed either on the r- ir axle or the flh drive shaft. This latter method onco Tj( went out of use, but Is now being re- jfjjjj vlved again by some rather prominent i -i i manufacturers. There are many ad- W vantages to this method The brake 'ytl drum is usually placed in the rear of 'tK the transml.lon and the brakes are rjj operated by a short shaft or rod. JffE This does away with many parts, and Hj5 also makes tho brakes more accessible X and easier to adjust. EXBSRS i nTii cnr; BRAKES Sternal contracting brakes arc dl- (tf 1 vlded Into two kinds: single acting ItS ;md double acting The single acting jjff type has only one continuous band 'ml which Is usually anchored at ono end. lf.i The free end is pulled or operated by irj 1 he brake rod. The type is usually Of held away from the brake drum b 'i small springs, so that the band does !( 1 not rub on the drum. The double act- rty will work equally well forward or 1M oackward, and eunsist.s of two p. tils, n upper and a lo ver half, The op erating levers are so attached that the name pull Is given to each section, and' I b one depends on the other for Its' braking power. Thn internal-expanding brake Is well thought of by many drivers, as! It is efficient, and seems to be gaining In favor In mountainous countries. Though not as powerful as the contracting con-tracting type, it cools better and does; not hac the tendency lo stick or1 freeze to the drum, locking the wheels ' Some of the higher grade of car are using this type of brakes with a good ii .ll of SI1C. I'fS. This brnke has two shoes which are lined either with some non-burning material made of fabric Interwoven with brass wire, or medium hard metal. This expands from the Inside of the brake drum, being operated by i cam. The brake drum is usually placed on the rear wheels. The external or contracting type. Is usually placed on the outside of the drum, the internal or expanding1 type is placed on the Inside. Somol ant have a double drum, each type 1 if brake operating on Its own drum Most types are op. rated by round iron or steel rods though some use i ables or small chains, also many combinations of chains, cables and ropes are used. One of the most Important Im-portant points is the proper adjustment adjust-ment of each so the pull is equalized and the brakes on each wheel work just the same and put forth the same pressure at the same time. This Is done by nn equalizing bar that is con-' nected from its center point to the j brake pedal shaft. When this pedal -Is pushed down this bar divides the pull equally between the two brakes I and the brake bands are adjusted the' same, tho yisame force will bo placed on each at the same time. no |