High efficiency early fuel evaporation carburetion system

Abstract

A carburetion system for improving cold starting of an automotive engine comprises a carburetor having an air-fuel passage, an air inlet to the passage, a fuel inlet to the passage for mixing fuel and air in the passage, and an outlet from the passage for delivering a mixture of an air and vaporized fuel to the engine. A heater comprising a ceramic resistor body of a material of positive temperature coefficient of resistivity has a plurality of relatively large passages extending in a pattern in spaced side-by-side relation to each other through the body between opposite ends of the body for defining thin webs of the resistor material between adjacent body passages. The heater is mounted at the outlet of the carburetor air-fuel passage with the heater passages aligned with the air-fuel passage to pass the air-fuel mixture through the heater passages in heat transfer relation to the body. Ohmic contacts are disposed on the inner walls of the heater body passages to provide a large area of ohmic contact to the resistor material. The ohmic contacts in alternate body passages are connected together at one end of the body while the ohmic contacts in the other body passages are connected together at the opposite end of the body, each group of interconnected ohmic contacts being connected to a system terminal extending around the side of the resistor body for directing electrical current through the thin webs of resistor material between ohmic contacts of opposite polarity in adjacent body passages, whereby the heater means is more efficiently operable in a 12 volt automotive power supply system to heat the air-fuel mixture for achieving improved fuel vaporization promptly after initiation of engine operation and for achieving improved flow of the air-fuel mixture to the engine.