PTC fuel heater for heating alcohol fuel

Claim 1

A fuel heater comprising: a container having an electrically insulated interior defining a fuel flow path and further having an inlet and an outlet, being connected to the opposite ends of said flow path for the passage of fuel therethrough; and a stack of generally planar foraminous PTC heaters disposed in said container in the flow path between the inlet and the outlet and arranged transversely of the flow direction of the flow of fuel; and an array of flat ring-like conductive elements, each having an electrical contact projecting from an edge thereof, the contact means of said array of elements being arranged in two rows, the electrical contact means in one row being arranged so as to be radially offset from the electrical contact means of the other row, each conductive element of each row being disposed between alternate PTC heaters in said stack, each of said conductive elements engaging substantially only the perimeter of the PTC heaters to leave the foraminous central portion thereof unobstructed to allow flow of fuel through said stack of PTC heaters from said inlet to said outlet; and a pair of radially offset channels disposed on the interior of said container; and electrical contact means of one row being disposed in one of said channels and electrical contact means of the other row being disposed in the other of said channels; and means connecting the outsides of the opposite end-most PTC heaters in the stack to the opposite sides of a power supply and means connecting the electrical contact means of said one row and the electrical contact means of said other row to opposite sides of the same power supply.