Heat exchanger with internal slotted manifold

Abstract

A heat exchanger that includes a manifold tube having a plurality of spaced apart openings formed through its wall in flow communication with a flow passageway, and a plurality of stacked flat tube elements each including a first plate and a second plate defining a flow channel therebetween, the plates each being provided with an aperture therethrough, the apertures in the first and second plates being substantially in alignment with each other. The manifold tube is received through the apertures in the first and second plates of each of the flat tube elements with each of the spaced apart openings in flow communication with the flow channel of a respective one of the flat tube elements. During assembly, the wall of the manifold tube is radially enlarged so that an outer surface of the manifold tube engages an inner surface surrounding the aperture in each of the first and second plates to secure the flat tube elements to the manifold tube. Also provided is a stacked plate heat exchanger having a manifold tube with an error proofing hole for ensuring a baffle cup is in place in the manifold tube, and a stacked plate heat exchanger having a manifold tube and a port fixture having an annular flow way in communication with a flow passage in the manifold tube through a plurality of radially spaced openings through the manifold tube.

What is claimed is:  
     
         1 . A heat exchanger comprising: 
 a manifold tube having a wall defining a flow passage therethrough and having a plurality of longitudinally spaced apart openings formed through the wall in flow communication with the flow passageway; and    a plurality of flat tube elements located along a longitudinal axis of the manifold tube, each including a first plate and a second plate defining a flow channel therebetween, the plates each being provided with an aperture therethrough, the apertures in the first and second plates of each of the tube elements being substantially in alignment with each other, the manifold tube being received through the apertures in the first and second plates of each of the flat tube elements with each of the spaced apart openings in flow communication with the flow channel of a respective one of the flat tube elements;    the wall of the manifold tube and the apertures being respectively sized that an outer surface of the manifold tube engages an inner surface surrounding the aperture in each of the first and second plates to secure the flat tube elements to the manifold tube, the flat tube elements being supported by the manifold tube.    
     
     
         2 . The heat exchanger of  claim 1  wherein the manifold tube is radially expanded at least along portions thereof where the outer surface engages the first and second plates of the flat tube elements.  
     
     
         3 . The heat exchanger according to  claim 1  wherein the inner surface of the aperture in the first and second plates that is engaged by the wall of the manifold tube is defined by an integral peripheral flange extending outward from the plate such that an overlap joint is formed between the wall and the peripheral flange, and the wall is brazed to the peripheral flange of each of the plates to seal a juncture therebetween.  
     
     
         4 . The heat exchanger according to  claim 1  wherein the first and second plates each have a substantially planar elongate central portion surrounded by a planar edge portion inwardly offset from and parallel to the planar central portion, the first and second plates of each flat tube element being joined together with the planar central portions spaced apart from each other to define the flow channel and the offset edge portion of the first plate abutting against the offset edge portion of the second plate.  
     
     
         5 . The heat exchanger or  claim 1  wherein, in at least some of the flat tube elements, the first plates and second plates are identical to each other.  
     
     
         6 . The heat exchanger according to  claim 1  wherein the flat tube elements are spaced apart from each other defining lateral passageways therebetween, and including fins located in the lateral passageways and in thermal contact with the flat tube elements.  
     
     
         7 . The heat exchanger of  claim 1  wherein the spaced apart openings include openings of more than one size.  
     
     
         8 . The heat exchanger of  claim 1  wherein the spaced apart openings are progressively larger along a length of the manifold tube.  
     
     
         9 . The heat exchanger of  claim 1  including at least one flat tube element having a flow channel that is in flow communication with the flow passage of the manifold tube through a plurality of radially spaced openings formed through the manifold tube wall.  
     
     
         10 . The heat exchanger of  claim 1  wherein the flat tube elements are spaced apart from each other and the spacing distance between the flat tube elements varies along the manifold tube.  
     
     
         11 . The heat exchanger of  claim 1  wherein the flow passage through the manifold tube is divided into first and second flow chambers with some of the flat tube elements being in flow communication with the first chamber and others of the flat tube elements being in flow communication with the second flow chamber.  
     
     
         12 . The heat exchanger of  claim 11  wherein a baffle cup located within the manifold tube divides the manifold tube into the first and second flow chambers, the baffle cup having a cylindrical wall having an outer surface in engagement with an inner surface of the manifold tube wall.  
     
     
         13 . The heat exchanger of  claim 12  wherein an error proofing opening is provided through the manifold tube wall at a location where the wall of the baffle cup overlaps the manifold tube wall, the error proofing opening being sized to permit visual confirmation of the presence of the wall of the baffle cup.  
     
     
         14 . The heat exchanger of  claim 1  including a mounting bracket having a collar engaging the manifold tube between two adjacent flat tube elements.  
     
     
         15 . The heat exchanger of  claim 1  wherein at least some of the flat tube elements include first and second plates having portions that are spaced further apart from each other closer to the manifold tube than further from the manifold tube to define a higher flow channel, relative to the longitudinal axis of the manifold tube, nearer the manifold tube than further from the manifold tube.  
     
     
         16 . The heat exchanger of  claim 1  including a port fixture mounted to the manifold tube, the port fixture defining a flow passageway that is in flow communication, through a port opening in the manifold, with the flow passage through the manifold tube, the port fixture including a collar surrounding an annular area of the manifold tube.  
     
     
         17 . The heat exchanger of  claim 16  wherein the collar of the port fixture defines an annular fluid flow way about the annular area of the manifold tube, the annular area having a plurality of radially spaced openings through which the annular fluid flow way is in flow communication with the flow passage through the manifold tube.  
     
     
         18 . The heat exchanger of  claim 17  wherein the collar is located between two adjacent flat tube elements.  
     
     
         19 . The heat exchanger of  claim 17  wherein the port fixture is a banjo-type fitting and the collar engages an end of the manifold tube.  
     
     
         20 . The heat exchanger of  claim 1  wherein the outer surface of the manifold tube engages substantially an entire circumference of the inner surface of the aperture in each of the plates in a butt-joint fashion.  
     
     
         21 . The heat exchanger of  claim 1  including a further manifold tube having a wall defining a flow passage therethrough and having a plurality of spaced apart openings formed through the wall in flow communication with the flow passageway, each of the plurality of first and second plates being provided with a further aperture therethrough, the manifold tube being received through the further apertures in the first and second plates of each of the flat tube elements with each of the spaced apart openings through the further manifold tube in flow communication with the flow channel of a respective one of the flat tube elements, the wall of the further manifold tube and the further apertures being respectively sized that an outer surface of the further manifold tube engages an inner surface surrounding the further aperture in each of the first and second plates to secure the flat tube elements to the further manifold tube, the flat tube elements being supported by the manifold tube and the further manifold tube; 
 the heat exchanger further including a inlet port in flow communication with the flow passage through the manifold tube, and an outlet port in flow communication with the flow passage through the further manifold tube.  
 
     
     
         22 . The heat exchanger of  claim 21  wherein the manifold openings though the manifold tube and the further manifold tube are inwardly oriented towards each other.  
     
     
         23 . The heat exchanger of  claim 21  wherein the manifold openings through the manifold tube and the further manifold tube are outwardly oriented away from each other.  
     
     
         24 . The heat exchanger of  claim 21  wherein the manifold tubes are joined together by a bypass manifold tube.  
     
     
         25 . The heat exchanger of  claim 24  wherein the bypass manifold tube includes fluid flow control means for controlling the flow of fluid therethrough.  
     
     
         26 . The heat exchanger of  claim 21  further including: 
 third and fourth elongate spaced-apart manifold tubes each having a wall defining a flow passage therethrough and having a plurality of longitudinally spaced apart manifold openings formed through the wall in flow communication with the flow passageway;  
 the first and second plates of the flat tube elements each having aligned third and fourth apertures therethrough receiving the third and fourth manifold tubes respectively,  
 a plurality of further flat tube elements including a first plate and a second plate defining a flow channel therebetween, the plates of the further flat tube elements each being provided with respectively aligned first, second third and fourth apertures therethrough receiving the manifold tube, the further manifold tube and the third and fourth manifold tubes respectively, the flow channel of each of the further flat tube elements being in communication at a first portion thereof with the flow passage of the third manifold tube through a respective one of the manifold openings in the third manifold tube and at a second portion thereof with the flow passage of the fourth manifold tube through a respective one of the manifold openings in the fourth manifold tube;  
 the wall of the third manifold tube being enlarged at least along portions thereof such that an outer surface of the third manifold tube engages an inner surface surrounding the third aperture in each of the first and second plates of the further flat tube element to secure the further flat tube elements to the third manifold tube, the wall of the fourth manifold tube being enlarged at least along portions thereof such that an outer surface of the fourth manifold tube engages an inner surface surrounding the fourth aperture in each of the first and second plates of the further flat tube element to secure the further flat tube elements to the fourth manifold tube,  
 the flat tube elements and further flat tube elements being interspersed adjacent each other.  
 
     
     
         27 . The heat exchanger of  claim 1  wherein the manifold tubes and flat tube elements are formed from polymers.  
     
     
         28 . A method of assembling a stacked plate heat exchanger, comprising: 
 (a) providing a manifold tube having a wall defining a flow passage therethrough and having a plurality of longitudinally spaced apart openings formed through the wall along a length thereof in flow communication with the flow passageway;    (b) providing a plurality of flat tube elements each including a first plate and a second plate defining a flow channel therebetween, the plates each being provided with an aperture therethrough, the apertures in the first and second plates of each of the flat tube elements being substantially in alignment with each other;    (c) positioning the-manifold tube-through the apertures in the first and second plates of each of the flat tube elements with each of the spaced apart openings in flow communication with the flow channel of a respective one of the flat tube elements; and    (d) radially expanding at least portions of the manifold tube such that manifold tube engages each of the first and second plates about the apertures thereof to secure the flat tube elements to the manifold tube.    
     
     
         29 . The method of  claim 28  wherein the flat tube elements are braze clad, and further including, subsequent to expansion step (d), applying heat to the manifold tube and flat tube elements to seal a joint between each of the first and second plates and the manifold tube.  
     
     
         30 . The method of  claim 28  wherein step (b) includes providing an integral peripheral flange around the apertures of the first and second plates, the peripheral flange of each aperture defining a circumference that is engaged by the radially expanded manifold tube.  
     
     
         31 . The method of  claim 28  wherein the manifold tube is radially expanded substantially uniformly along substantially an entire length thereof.  
     
     
         32 . The method of  claim 28  wherein the manifold tube is selectively radially expanded in a vicinity of each of the flat tube elements.  
     
     
         33 . The method of  claim 28  wherein the manifold tube is radially expanded using a hydraulic bladder.  
     
     
         34 . The method of  claim 28  including providing fins between and in thermal contact with adjacent flat tube elements.  
     
     
         35 . The method of  claim 34  including assembling a core stack by aligning stacked alternating flat tube elements and fins to a desired height with the apertures in alignment and subsequently inserting the manifold tube through the aligned apertures.  
     
     
         36 . The method of  claim 34  including assembling a core stack by building up flat tube elements on the manifold tube.  
     
     
         37 . The method of  claim 34  including compressing a core stack comprising the flat tube elements and the fins prior to radially expanding the manifold tube.  
     
     
         38 . The method of  claim 28  wherein said step (b) of providing a plurality of flat tube elements includes roll forming substantially identical first and second plates each with a central planer portion having longitudinal edge flanges provided along both longitudinal side edges thereof for joining the first and second plates together; cutting the roll formed first and second plates at a desired length and forming ends thereon, and piercing the apertures through the first and second plates.  
     
     
         39 . A heat exchanger comprising a manifold tube having a wall defining a fluid flow passage therethrough; a stack of flat tube elements connected to the manifold tube and each having a flow channel therethrough in fluid communication with the fluid flow passage; and a baffle cup having a wall engaging an inner surface of the manifold tube wall, the manifold tube wall having an error proofing hole formed therethrough at a location where the baffle cup wall is positioned, the hole being sized such that a visual check can be performed to ensure that the baffle cup is in place, the error proofing hole being sealably covered by the wall of the baffle cup.  
     
     
         40 . A heat exchanger comprising a manifold tube having a wall defining a fluid flow passage therethrough; a stack of flat tube elements connected to the manifold tube and each having a flow channel therethrough in flow communication with the fluid flow passage; and a port fixture having a collar providing a flow way surrounding at least a portion of the manifold tube wall having a plurality of spaced openings formed therethrough, the flow way being in flow communication with the fluid flow passage through the spaced openings, the port fixture having a connecting member extending from the collar and defining a fluid passageway in flow communication with the flow way.  
     
     
         41 . The heat exchanger according to  claim 40  wherein the collar includes an annular wall having a first end wall formed at one end thereof and a second end wall formed at an opposite end thereof, the first and second end walls each having an opening therethrough through which the manifold tube passes, the annular wall and first and second end walls defining the flow way.  
     
     
         42 . The heat exchanger according to  claim 40  wherein the port fixture is a banjo-type fitting, and the collar includes an annular wall having a first end wall formed at one end thereof and a second end wall formed at an opposite end thereof, the first end wall having an opening therethrough through which the manifold tube passes, an end of the manifold tube being positioned within the collar, the annular wall and first and second end walls defining the flow way.  
     
     
         43 . The heat exchanger according to  claim 40  wherein the manifold tube passes internally through openings provided through the flat tube elements and the collar of the port fixture includes an annular wall having a first end that is sealably engaged by an annular portion of one of the flat tube elements surrounding the manifold tube, and a second end that is sealably engaged by an annular portion of a further one of the flat tube elements surrounding the manifold tube, the annular wall and said annular portions defining the flow way.