Patent ID: 7090488

Claim:
A heat treatment furnace wherein a heating zone ( 4 ), a cooling zone ( 5 ), and a quenching zone ( 6 ) are provided inside a linear furnace body in this order, the heating zone ( 4 ), the cooling zone ( 5 ), and the quenching zone ( 6 ) being separated by partition doors ( 2 , 3 ), conveying means of a work (W) being a tray pusher ( 7 ) in the heating zone ( 4 ), conveying means of the work (W) comprising roller hearths ( 8 , 9 ) in the cooling zone ( 5 ) and the quenching zone ( 6 ), the roller hearths ( 8 , 9 ) being independently driven, wherein a front end of the roller hearth ( 8 ) belonging to the cooling zone ( 5 ) resides inside the heating zone ( 4 ) at the rear end of the heating zone ( 4 ), and wherein the front end of the roller hearth ( 8 ), which belongs to the cooling zone ( 5 ), resides inside the heating zone ( 4 ) by the length of one block of the work (W) from the partition door ( 2 ), which separates the heating zone ( 4 ) from the cooling zone ( 5 ), and a rear end of a work conveyor rail ( 33 ) provided in the heating zone ( 4 ) is connected to the front end of the roller hearth ( 8 ) in order to convey the work (W).