Rate-of-use fuel consumption indicator for combustion engines

An arrangement for indicating the on-going fuel consumption of an operating internal combustion engine in a motor vehicle having a multi-stage transmission, comprising:

• means for sensing an engine operating parameter indicative of the quantity of fuel being supplied to the engine per engine revolution;
• an indicating instrument;
• means for transmitting to said instrument a signal representative of the sensed parameter;
• and means for modulating the signal as a function of the currently engaged stage of the transmission;
• said sensing means comprising a valve movable in response to changes in the engaged transmission stage to a plurality of positions each of which corresponds to a different engaged stage;
• and wherein said modulating means comprises a transducer having a housing, a pair of diaphragms of differential surface areas, a member connecting and movable with said diaphragms and defining with the same a chamber and a port communicating said chamber with said valve, said chamber being subjected to different pressures in dependence upon the position of said valve.

An arrangement for indicating the on-going fuel consumption of an operating internal combustion engine in a motor vehicle having a multi-stage transmission, comprising:

• means for sensing an engine operating parameter indicative of the quantity of fuel being supplied to the engine per engine revolution;
• an indicating instrument;
• means for transmitting to said instrument a signal representative of the sensed parameter;
• and means for modulating the signal as a function of the currently engaged stage of the transmission;
• a valve plate cooperating with a suction manifold valve seat and with an air valve seat which is coaxial thereto;
• said modulating means comprising a pressure transducer including three separate diaphragms each having a different surface area and means rigidly connecting said diaphragms to said valve plate, the diaphragm having the smallest surface area defining with a housing portion of the transducer a first chamber and with the next-larger diaphragm a first compartment, said next-larger diaphragm defining with the largest diaphragm a second compartment and said largest diaphragm defining with another housing portion a second chamber communicating with said transmitting means;
• and means for connecting said first chamber and first and second compartments to atmospheric pressure or to negative pressure in dependence upon the respectively engaged transmission stage, to thereby modulate the pressure in said second chamber which constitutes said signal.