Abstract A passage for returning gases from a gasoline engine crankcase to the carburetor and for preventing flame from propagating along the tube in the direction of the crankcase consists of a brass tube having an interior strip with a width equal to the internal diameter of the tube wound into a spiral along its length and fixed within the tube. Gasses passing through the tube are thus forced into a spiral path, cooling and breaking up any flames propagating along the tube. An alternative embodiment of the feed tube is used to communicate the air side of an engine diaphragm fuel pump to the carburetor so as to dispose of fuel reaching the air side in the event of rupture of the diaphragm. The tubes are formed by tinning the elongated edges of the spiral strip with a brazing compound, inserting the strip into the tube, and heating the exterior of the tube so as to braze the edges to the interior wall.
In a combustion engine having a carburetor for mixing air with fuel, a feed line for conveying combustible gases from a source to the carburetor including an elongated section of closed tube having one open end connected directly to the source and the other end connected to the carburetor so as to pass undiluted gases from the source directly to the carburetor, said tube having an interior flame arresting baffle formed of an elongated strip twisted about its elongated axis and having both of its longitudinal edges fixed to the interior of the tube so that the longitudinal axis of the strip coincides with the longitudinal axis of the tube and having one end terminating at the carburetor end of the tube.
Claim 2
Dependent Claim
122 words
In a combustion engine having a carburetor for mixing air with fuel, a feed line for conveying combustible gases from a source to the carburetor including an elongated section of closed tube having one open end connected directly to the source and the other end connected to the carburetor so as to pass undiluted gases from the source directly to the carburetor, said tube having an interior flame arresting baffle formed of an elongated strip twisted about its elongated axis and having both of its longitudinal edges fixed to the interior of the tube so that the longitudinal axis of the strip coincides with the longitudinal axis of the tube and having one end terminating at the carburetor end of the tube.
Claim 3
Dependent Claim
16 words
The engine of claim 1 wherein the source of combustible gases consists of the engine crankcase.
Claim 4
Dependent Claim
25 words
The engine of claim 1 wherein the source of combustible gases consists of the air side of a diaphragm type fuel pump for said engine.
Claim 5
Dependent Claim
20 words
The feed line of claim 1 wherein said elongated strip extends beyond the end of the tube at the carburetor.