RUBBER.

Press, Volume LXIII, Issue 19150, 5 November 1927, Page 5

RUBBER.

USB IN, MOTOR.VIfIfIICLKS. Rubber ii noming into mor* exten* *ive use in mQter*Ti»bicle construction aside from its largest, and. most important employment in tyres. It has long teen used for hose connexions, fan twite, windshield strips, floor »nd step mats, and door bumpers, but in recent years, as pointed out by C. Saurer at a recent meeting of the Indiana .section of the/'Society of Automotive Engineers, development of rubber' universal joints, radius-rod supports, torque joints, balancers, engine, supports, and spring mountings have been made. Mnch Experimental Work. A great deal of experimental work" has been done to develop a suitable compound and manufacturing processes for the, production of rubber shims, to be inserted between the chassis frame and car ' body, which will not be .affected It heat and will have.a long life. ' Rubber axle bumpers and other moulded parts can be made of a composition that will outlast the vehicle.

Rubber shock insulator mountings now applied to motor vehicle*, particularly motor coaches, include spring shackles, torque insulators, and mountings tor the engine transmission, radiator, steering post, petrol tank, passenger seats, and motortruck cab, said Charles Froesch. Absorbs Shocks Quickly.

The main advantages of rubber as a shock absorber, it was said; lies in the fact that it absorbs shocks quickly and stores them nearly fifty' times as long as steel, which continues to vibrate for a considerable time after shock, because the energy is absorbed slowly.

Rubber will withstand stretching to ten or - eleven times its length without rupture or appreciable permanent deformation. Its tensile, strength calculated oa it* cross section at the instant of breakage j* 50,000 pounds per square inch, which approaches that of steel.

Absorbing Power of Subfawr. If * one-inch cube of rubber is stretched to eleven inches by a load of 4000 pounds, the rubber will have absorbed 1600 foot pounds of energy, he *aid, and one pound of rubber, occupying about twenty-five cubic inches, will absorb 40,000 foot pounds. If the -elongation occurs in cycles Johme minute, the rubber will "absorb energy equal to one and one-quarter.horse-power. A. steel aprinu capable of doing this would weigh from fifty to one hundred pounds, he said, depending on the type of steel used.

The properties of rubber are approached by a steel spring in a <jasnypbt,but rubber is a. combined spring and 6hock absorber, within itselfl