MOTORING

Hawera Star, Volume XLVII, 7 January 1928, Page 13

MOTORING

RUBBER AND VIBRATION absorbing shook. lii recent years many new uses have been found for rubber in automobile production, and there are good reasons for believing that the applications of this material will he developed still farther. In the days of low speed engines and rough roads most of the shocks experienced by motorists resulted from road obstacles, and even then the most effective shock absotoer was a rubber product —the pneumatic tyre. With the increase in engine speeds and the improvement in roads there has been a shifting of the relative importance of sources of vibration and to-day various unpleasant forms of roughness and noise have their origin in the engine, fu the four-cylinder type we have the unbalanced secondary force and in engines with more than four cylinders we often have torsional vibration at certain critical speeds. The occupants of the car know of the existence of these vibrations only through their transmission to the chassis and thence to the body, and if such transmission -can be prevented the actual engine vibration becomes much less objectionable. It, is for this reason that rubber cushions are now widely used foi engine supports, rubber or rubberised- fabiic spring connections are coming into use, rubber centres are inserted in clutches to prevent the transmission of irregularities in the torque impressed on that part. Even the steering gear is now in some cases provided with a flexible member of rubber or rubberised fabric to protect the hands and arms of the driver against road shock.