Header plate and heat exchanger comprising same
The invention concerns a header plate, preferably for a heat exchanger, such as water cooled charge air cooler (WCCAC), comprising a coolant housing having two opposing walls made up from two header plates ( 11, 12 ), which are made of sheet metal of a defined thickness (t). The header plates ( 11, 12 ) form parts of air tanks and are passed by air tubes extending through said coolant housing from one of said header plates ( 11, 12 ) to the other. The header plates ( 11, 12 ) have stamped apertures ( 15 ), in which said air tubes are inserted and tightly connected to the header plate sheet metal. The apertures ( 15 ) have peripheral rims ( 22 ), which protrude on one side of the header plate ( 11, 12 ) in question and give an extra support to the air tubes inserted in the apertures ( 15 ) of said header plate ( 11, 12 ). The distance (da) between adjacent apertures ( 15 ) and thus the distance (dt) between adjacent air tubes is less than two times the thickness (t) of the header plate sheet metal.
1. A header plate ( 11 , 12 ) made of sheet metal of a defined thickness (t), the header plate ( 11 , 12 ) comprising:
oblong stamped apertures ( 15 ) for receiving air tubes ( 6 ) suitable to be inserted into the header plate ( 11 , 12 ), said apertures ( 15 ) having peripheral rims ( 22 );
wherein the sheet metal of said header plate ( 11 , 12 ) around a periphery of said stamped apertures ( 15 ) forms the peripheral rims ( 22 ), which protrude on one side of the header plate ( 11 , 12 ) and give an extra support to the air tubes ( 6 ) when these are inserted in the apertures ( 15 ) of said header plate ( 11 , 12 ); and
a distance (da) between of adjacent apertures ( 15 ) and thus a distance (dt) between adjacent air tubes ( 6 ) is less than two times the defined thickness (t) of of the sheet metal of said header plate ( 11 , 12 ), wherein said distance (da) between adjacent apertures ( 15 ) and thus the distance (dt) between adjacent air tubes ( 6 ) is measured between short sides of the oblong apertures ( 15 ) and thus between narrower sides of adjacent air tubes ( 6 ), said peripheral rims ( 22 ) having a wall thickness less than the defined thickness of said header plate ( 11 , 12 ).
2. A header plate ( 11 , 12 ) according to claim 1 , wherein said header plate ( 11 , 12 ) is channel-shaped having a centre web ( 16 ), in which said apertures ( 15 ) are provided, and flanges ( 17 , 18 ) extending along said centre web ( 16 ).
3. A header plate ( 11 , 12 ) according to claim 2 , wherein the rims ( 22 ) of said apertures ( 15 ) and said flanges ( 17 , 18 ) protrude on the same side of the header plate ( 11 , 12 ) and wherein the distance (di) between an inner face of either flange ( 17 , 18 ) and apertures ( 15 ) adjacent to said inner face is less than three times the thickness (t) of the header plate sheet metal.
4. A header plate according to claim 3 , wherein insertion spaces ( 26 , 27 ) are provided between said flanges ( 17 , 18 ) and rims ( 22 ) of adjacent apertures ( 15 ) for receiving edge portions ( 23 , 24 ) of casing walls ( 9 , 10 ).
5. A header plate ( 11 , 12 ) according to claim 1 , wherein said header plate ( 11 , 12 ) and the air tubes ( 6 ) are clad and pre-fluxed in order to be brazeable in an oven after insertion of the air tubes ( 6 ) into said apertures ( 15 ).
6. A heat exchanger ( 1 ) comprising a coolant housing passed by a plurality of air tubes ( 6 ), characterized in that said air tubes ( 6 ) are inserted in and attached to rimmed apertures ( 15 ) in at least one header plate ( 11 , 12 ) according to claim 1 .
7. A heat exchanger ( 6 ) according to claim 6 , wherein said coolant housing ( 7 ) comprises two opposing side walls made up from two header plates ( 11 , 12 ), wherein on at least one of the two header plates ( 11 , 12 ), the rims ( 22 ) of the apertures ( 15 ) protrude from said at least one header plate ( 11 , 12 ) on the header plate side turned away from the opposite header plate ( 11 , 12 ).
8. A heat exchanger ( 1 ) according to claim 6 , wherein said coolant housing ( 7 ) comprises two opposing side walls made up from two header plates ( 11 , 12 ), wherein on at least one of the two header plates ( 11 , 12 ) the rims ( 22 ) of the apertures ( 15 ) protrude from said at least one header plate ( 11 , 12 ) on the header plate side facing the opposite header plate ( 11 , 12 ).
9. A heat exchanger ( 1 ) according to claim 6 , wherein the heat exchanger ( 1 ) is a multi-rows exchanger and wherein the distance (da) between adjacent apertures ( 15 ) is the same between all adjacent apertures ( 15 ) of the header plate ( 11 , 12 ).