Patent ID: 9290079
Filing Date: 2016-03-22
CPC Classification: B60H,F23C,F23D,F23M

Claim Text:
1. A vehicle heater comprising a burner arrangement, the burner arrangement comprising: a combustion chamber; a flame tube with a waste gas outlet end area, said flame tube carrying combustion waste gases away from said combustion chamber and extending elongated in a direction of a longitudinal axis with a constant cross sectional area; a heat exchanger housing with a circumferential wall, which surrounds said flame tube and defines a waste gas backflow space extending essentially annularly about the longitudinal axis and with a bottom area located opposite said waste gas outlet end area of said flame tube, said heat exchanger housing having a waste gas outlet for releasing combustion waste gases from said waste gas backflow space in an outlet circumferential area of said heat exchanger housing, wherein a flow cross section provided between said flame tube and said circumferential wall in a first axial area of said waste gas backflow space is smaller in said outlet circumferential area than in a circumferential area located opposite the outlet circumferential area in relation to the longitudinal axis, and a flow cross section in said outlet circumferential area increases in an expansion area following said first axial area in an axial direction, wherein at least one of: a flow cross section in the outlet circumferential area in a direction of said waste gas outlet in a second axial area following said expansion area corresponds essentially to a flow cross section in an opposite circumferential area; and a flow cross section increases in a stepped manner in said expansion area.