Combined carburetor and impulse fuel pump

A combined carburetor and liquid fuel pump wherein the carburetor is of the type comprising a body that defines a mixing passage into which fuel is aspirated from a float bowl and the fuel pump is of the type comprising a resilient pump membrane that has portions which provide flatwise swingable flapper-type inlet and outlet check valves and another imperforate portion comprising a diaphragm that separates a pair of pumping chambers, one of said pumping chambers being an actuating chamber communicated with a source of pulsating pressure by which the diaphragm is flexed and the other of said pumping chambers being a liquid chamber into which fuel is drawn past the inlet check valve and from which it is expelled past the outlet check valve, said combined carburetor and liquid fuel pump being characterized by:

• A. the carburetor body
• (1) having a flat, vertical exterior surface which is overlain by said pump membrane and
• (2) having a cavity which opens to said surface and defines one of said pumping chambers;
• B. a pump body having opposite flat inner and outer surfaces, said pump body being secured to the carburetor body with its said surfaces vertical and its inner surface in flatwise opposing relation to said exterior surface on the carburetor body and cooperating therewith to sealingly clamp the pump membrane;
• C. said pump body having a cavity that opens to its said inner surface and is opposite said cavity in the carburetor body to provide the other pumping chamber;
• D. said pump body also having a pair of cavities opening to its said outer flat surface,
• (1) one of which has a portion near the bottom of the pump body and provides for an inlet surge chamber, and
• (2) the other of which has a portion near the top of the pump body and provides for an outlet surge chamber;
• E. an imperforate flexible membrane overlying said outer flat surface of the pump body to cooperate with said pair of cavities in defining said surge chambers and which, by its flatwise flexing, provides for expansion and contraction of said surge chambers;
• E. a cover member secured to the pump body and overlying the imperforate membrane to sealingly clamp the same against said outer surface on the pump body, said cover member having an inwardly opening recess opposite each of said surge chambers into which an underlying area of the imperforate membrane can flex for expansion of the surge chambers;
• and
• G. each of said bodies having passage portions which open to mouths at the flat surface on the body that opposes the flat surface on the other body, each passage portion in one body being communicated through the pump membrane with a complementary passage portion in the other body, said passage portions defining
• (1) an inlet passage that leads from said portion of said cavity that defines the inlet surge chamber, past the inlet check valve, to the liquid chamber,
• (2) an outlet passage that leads from the liquid chamber past the outlet check valve to said portion of said cavity that defines the outlet surge chamber, and
• (3) a delivery passage that leads from a bottom portion of said cavity that defines the outlet surge chamber to a float controlled inlet to the float bowl.