GB623412A - Meter for indicating fuel consumption - Google Patents

Abstract

623,412. Fuel consumption meters. BOSE, B. N. Sept. 3, 1946, No. 26471. [Class 106 (iii)] In a fuel consumption meter for a motor vehicle of the type comprising, in combination, a fuel metering device for issuing a predetermined volume of fuel for consumption by the motor and means for indicating the distance travelled by the vehicle during the consumption of the predetermined volume of fuel, the indicating means includes a distance follower member moved according to the distance travelled by the vehicle during the measuring period, and a pointer connected to the member through a lost-motion device, the pointer being locked during the measuring period in the position in which it was just before the commencement of the measuring period and only being released and moved into the new position determined by the movement of the distance follower member during the measuring period under the control of the lost-motion device at or towards the end of the measuring period. Fuel enters the meter through a passage 2, Fig. 1, and is continuously fed to the motor through a pipe 4. The flow through passage 2 is normally in excess of the amount taken by the motor, and as the level rises in the chamber 1, an annular float 3 rises until it reaches a stop 5 on the valve stem 6. A further slight rise lifts the valve stem and shuts off the flow through the passage 2, the valve snapping into this position by virtue of springs 7 co-operating with a groove 9 in the stem. From this point the fuel supply to the engine is derived solely from the measured quantity in the chamber 1, and the float moves down until it reaches a lower stop 10 when further movement snaps open the valve again. The means for indicating the distance travelled comprises a worm 19, Fig. 3, driven, e.g. from the transmission shaft, adapted to drive a toothed sector 14 pivoted to a stirrup-shaped member 13 vertically slidable in guides 16. The clockwise movement of a lever 11, Fig. 1, pivoted to the valve stem 6, caused when the valve is closed by the float 3, acts through a spring 20 to press the toothed sector 14 into engagement with the worm 19. The sector is then driven counter-clockwise against a spiral spring 35 until the opening of valve 2 causes it to be disengaged. The sector 14 is coupled to a pointer 23, Fig. 3, by another spiral spring 21 constituting a lost-motion device. A drum 24 fixed to the pointer spindle is normally held by a pair of flat springs 25 pressing on its surface, but as the lever 11 rocks at the opening of valve 2, a pawl 29 pulls a ratchet-wheel 30 round one tooth-space together with a cam 28 which momentarily depresses a leaf 31 engaging the springs 25, causing the latter to bow outwards and so release the pointer, allowing it to assume a position corresponding with the maximum displacement of the sector 14.