Fuel consumption calculator for vehicles - has mutually rotatable scale discs to show consumption per 100 KM

摘要

The calculator has two relatively rotatable discs with linear scales to obtain distance travelled by subtraction and two further relatively rotatable discs with logarithmic scales for calculation of the fuel consumption per 100 km from the fuel consumed and the distance. Pref. a fixed disc has two logarithmic scales, one with values from 10 to 100 to set the fuel tank contents and the other with valves from 100 to 1000 to set the distance. One of the scales is visible through a window in a rotatable disc so that when an index mark on the rotatable disc is set to the value giving fuel tank contents the fuel consumption per 100 km can be read off below the distance value on the rotatable disc scale.