Patent EP-2264192-A1 (EP)
Inventor: BELLEN PASCAL
IPC: C21D1/10
Filed: 2010-06-15
Abstract: The hardening machine comprises an inductor (5) that is positioned for heating a part of the workpiece on the workpiece, a quenching spray (25) for a coolant for quenching the heated part of the workpiece, a protective gas connection through which the protective gas is guided during heating and/or quenching, and a protective gas hood (10) that is arranged on the workpiece so that a protective gas chamber (24) partially surrounding the part to be hardened emerges in which the inductor, the quenching spray and the protective gas connection are arranged. The hardening machine comprises an inductor (5) that is positioned for heating a part of the workpiece on the workpiece, a quenching spray (25) for a coolant for quenching the heated part of the workpiece, a protective gas connection through which the protective gas is guided during heating and/or quenching, and a protective gas hood (10) that is arranged on the workpiece so that a protective gas chamber (24) partially surrounding the part to be hardened emerges in which the inductor, the quenching spray and the protective gas connection are arranged. The protective gas hood comprises two side walls (23) that are positionable adjoining to the area to be hardened with an edge on a wall of the workpiece. The protective gas hood comprises a rear wall intended to the workpiece, where the rear wall connects the side wall. The protective gas connection and the quenching spray are arranged between the protective gas hood and the workpiece. The inductor, the protective gas connection and the quenching spray are movable for hardening a part of the workpiece along the part of the workpiece to a movable direction. The protective gas connection is arranged in movable direction towards the inductor. The quenching spray is arranged towards the protective gas connection in the moving direction and a hood part is arranged in the movement direction towards the workpiece. The hood part remains in its position against the workpiece during heating and/or quenching. The inductor and the protective gas connection are movable in the hood part so that the part of the workpiece to be hardened is quenched by the quenching spray. The moving direction passes in vertical direction from bottom towards top so that the hood part is arranged in vertical direction and the protective gas hood lateral to the workpiece that is arranged to the protective gas connection in vertical direction below the inductor. The quenching spray is arranged in vertical direction below the protective gas connection. The moving direction with a vertical passing solder includes a sharp angle and passes from bottom towards top. The hood part comprises side walls and cover walls, where the side walls comprises a closed form in a horizontal section and is arranged to the workpiece so that the edge of the side wall turned to the workpiece is partially superimposed on a wall of the workpiece vertically passing on the part to be hardened to the movement direction in the area of heating. The edge of the side wall is intended to the workpiece enclosed with the cover wall. A further protective gas connection arranged in the movement direction is arranged above the inductor. The inductor, the protective gas connection and the quenching spray are held on the protective gas hood and the protective gas hood is movable in movement direction along the part of the workpiece to be hardened. The protective gas hood is partially movable in the hood part and comprises a further side wall that is arranged in the area of the edges of the side wall in the movement direction before the inductor and encloses the wall of the workpiece turned to the protective gas hood. The further side wall has a further protective gas connection that is arranged so that the protective gas flows in the direction of the workpiece and/or the movement direction. The side wall of the protective gas hood extends itself in the movement direction from the quenching spray up to the hood part. The inductor, the protective gas connection and the quenching spray are mounted on a holder that is movable within the protective gas hood and the hood part to the movement direction. The protective gas hood and the hood part are tightly connected and change its position against the workpiece during heating and/or quenching. The hood part comprises a discharge opening. A suction unit is arranged to the discharge opening of the hood part for producing a flow of the protective gas in the movement direction. The sides of the side wall of the protective gas hood turned away from the hood are arranged to the workpiece. The quenching spray is oriented so that a column is sealable between the edge of the side wall of the protective gas hood and the wall of the workpiece. An antenna is arranged for automatic positioning of the hardening machine to the workpiece. A lower pressure of the protective gas is produced in the protective gas chamber by the antenna. The workpiece of individual teeth comprises gears with tooth profiles to be hardened, where two tooth profiles are movable during heating the inductor on the tooth base.