Abstract: A heat exchanger finned tube 10 for use in fabricating a heat exchanger 1 useful as the evaporator for refrigerators or the like wherein a hydrocarbon refrigerant is used. Two tube insertion holes spaced apart from each other are formed in each of plate fins 12, and two straight tube portions 11a of a hairpin tube 11 are inserted through the respective holes of each plate fin to arrange the plate fins 12 in parallel into a plurality of fin groups 13 spaced apart on the straight tube portions 11a longitudinally thereof. The hairpin tube 11 is enlarged with use of a fluid to fixedly fit the plate fins 12 of each tin group 13 around an enlarged tube portion 14 of the hairpin tube 11 and provide a finless part 19 between each pair of adjacent fin groups 13 on each of the straight tube portions 11a. A restrained small-diameter portion 15 is provided in each of the finless parts 19 of each straight tube portion 11a.

Abstract: A cooling system is provided with a heat exchanger that has a thermally conductive tube over-molded with a plurality of thermally conductive fins. To form the heat exchanger, a thermally conductive tube is provided. Insert molding, over molding or injection molding is utilized to incorporate thermally conductive fins with the thermally conductive tubes. The molding process may also simultaneously create any required features, such as mounting features and fittings for tubing to be connected to the heat exchanger.

Abstract: A heat exchanger fin includes a plurality of vortex generator louvers spaced apart, such that there is a gap between adjacent louvers through which a fluid, such as air, flows. Each vortex generator louver is provided with one or more mini-vortex generators along an outer edge of the louver. The mini-vortex generators trigger vortices that flow across the vortex generator louvers.

Abstract: A fin is disclosed for use in a heat exchanger coils including tube segments extending through the fin. The fin includes a corrugated sheet of material having a plurality of major corrugations, about 8 to about 24 corrugations per inch (2.54 cm), each major corrugation being a peak or a valley with an amplitude “h” at the peaks or the valleys perpendicular to a reference major plane equally bisecting the major corrugations, and a width “w”; a plurality of orifices; a collar perpendicular to the reference major plane and extending from the sheet around each of the orifices; and a generally flat area that is generally parallel to or generally coextensive with the reference major plane and that surrounds each collar. The major corrugations have angled walls extending from at least one of the peaks and valleys to the generally flat areas adapted to create a vortex when air travels over the fin. A ratio of “h” to “w” is about 0.32 to about 0.7.

Abstract: A method of manufacturing metal fins suitable for use in a heat exchanger which includes providing a coated patterned fin stock having a series of parallel stripes disposed longitudinally across the width of one surface of the fin stock. The stripe pattern is evenly spaced in the central portion of the fin stock, and staggered or more further spaced apart at the edges of said fin stock. The fin stock is passed through a series of forming dies to form or draw a plurality of tube receiving collared holes in the fin stock, followed by slitting or cutting the fin stock longitudinally to form a plurality of fin strips. The staggered spacing compensates for transverse movement of the fin stock during the drawing operation, and assures for accurate positioning of the collars between the fin stripes. The invention also includes the use of the fins in a high density coil design for use in a heat exchanger.

Abstract: A heat exchanger includes at least two ducts for separating a first heat exchange fluid, inside the ducts, from a second heat exchange fluid, outside the ducts, the ducts having longitudinal axes that are substantially parallel to one another. A substantially planar cooling element is formed with apertures through which the ducts extend. The cooling element is inclined at a first predetermined acute angle to the longitudinal axes of the ducts. The cooling element is provided with louvers that are inclined at a second predetermined acute angle to the general plane of the cooling element. The first and second predetermined acute angles are substantially equal in magnitude.

Abstract: The invention relates to a cooler having means for directing a cooling medium, means for directing a medium to be cooled, and an essentially axially symmetrical housing. The means for directing the medium to be cooled is arranged in such a way that the medium to be cooled, in at least one first region, flows in an essentially axial direction, and the medium to be cooled, in at least one second region, flows in a direction having a radial component. The invention also relates to a method of cooling a medium and to various uses of a cooler according to the invention.

Abstract: A fin is disclosed for use in a heat exchanger coils including tube segments extending through the fin. The fin includes a corrugated sheet of material having a plurality of major corrugations, about 8 to about 24 corrugations per inch (2.54 cm), each major corrugation being a peak or a valley with an amplitude “h” at the peaks or the valleys perpendicular to a reference major plane equally bisecting the major corrugations, and a width “w”; a plurality of orifices; a collar perpendicular to the reference major plane and extending from the sheet around each of the orifices; and a generally flat area that is generally parallel to or generally coextensive with the reference major plane and that surrounds each collar. The major corrugations have angled walls extending from at least one of the peaks and valleys to the generally flat areas adapted to create a vortex when air travels over the fin. A ratio of “h” to “w” is about 0.32 to about 0.7.

Abstract: An evaporative heat exchanger of a medium condenser of a air/conditioning system with less cooling fins or even without cooling fins. The evaporative heat exchanger is composed of a plurality of streamline cross sectional tubes used instead of conventional round tubes for providing an evaporative efficiency, and being easy to clean and maintain.

Abstract: A plurality of angle portions 2c of the fins on an upstream side and those on a downstream side of an air flow are provided so as to be substantially symmetrical with each other. Due to this, bending forces are continuously exerted on a thin plate-like fin material in a direction where the bending deformation of the fin material is cancelled, during the fin forming process. Accordingly, when the angle portions 2c are formed it can be prevented in advance that the fin material 11 is deformed in a state where the repeated deformations of the fin material 11 are accumulated in the same direction.

Abstract: A fin for a heat sink is provided that includes a plate having a surface and an edge and at least one vane projecting outwardly from the surface and arranged relative to the edge so as to redirect a portion of a stream of air that is impinging upon the edge. A heat transfer system is also provided that includes a heat pipe having an elongate side and a fan that is arranged so as to direct a stream of air toward the elongate side of the heat pipe. At least one plate is arranged in parallel relation to a stream of air created by the fan. The plate includes an opening with the heat pipe positioned within the opening, a surface and an edge and at least one vane projecting outwardly from the surface and arranged relative to the edge so as to redirect a portion of the stream of air that is impinging upon the edge from the fan.

Abstract: A heat transfer device of a heat exchanger capable of promoting the heat transfer action thereof and reducing the pressure loss thereof by reducing a peeling wake area at the rear of a heat transfer tube, comprising a linear or tubular heat transfer body (T) coming into contact with a heat transfer fluid (A) for heat transfer and heat transfer fins (F) integrally formed so as to transfer heat to the heat transfer body, the heat transfer fins further comprising guide fins (10) disposed near the heat transfer body, wherein the guide fins guide the heat transfer fluid to the rear of the heat transfer body to reduce the peeling wake area (C) at the rear of the heat transfer body, and the peeling point positions (B) of the heat transfer fluid are set at angular positions (&bgr;) of 90° or more from the stagnation point (E) of the heat transfer body by setting the angle of attack (&agr;), shape, position, and dimensional ratio of the guide fins.

Abstract: A circulation path, a radiator and a reserve tank which can remove air bubbles from the fluid passageway, constitute parts of a closed circulation path, and are formed by joining a flow path wall-forming radiation board on which curved surfaces as flow path walls are formed, with a flat plate-like flow path wall-forming radiation board as another curved surface by welding or the like. Therefore, the efficiency of heat exchange of a cooling apparatus for electronic equipment can be improved, removal of air bubbles from the flow passageway and reduction in size, weight and thickness is made possible without causing air lock.

Abstract: A heat exchanger is provided for a refrigerator and includes one or more refrigerant tubes for refrigerant flow, and a plurality of straight fins having lengths different from each other fitted to the refrigerant tubes at fixed intervals in parallel to each other by means of through holes formed therein. The heat exchanger includes sections having different intervals or spaces between fins, wherein sections with the smallest fin spaces have a size 75% or less of a total size of the heat exchanger.

Abstract: A heat exchanger coil assembly is provided. The fins of the assembly include lance style enhancements on a corrugated shape of the fin. Lances are provided on both the upstream and the downstream sides of each corrugation. The upstream lance forms a first angle with respect to a direction of mean airflow and the downstream lance forms a second angle with respect to the direction of mean airflow. The first and second angles are not equal, such that the lances are canted with respect to one another. This generates two different streams of air flow such that a wake of the upstream lance will not impinge on the downstream lance, thereby maximizing heat transfer for both the upstream and the downstream lances.

Abstract: Baffles (20, 22) arranged alongside a plurality of conduits (12).

Abstract: Welds (111a) are provided in areas that are offset from curved portions (111b) where stress concentration is likely to occur. This allows excess stress to be inhibited to occur at the welds at the time of tube enlargement. Therefore, even if the welds are softened and proof stress (mechanical strength) is reduced at the time of welding, as the stress occurring at the welds at the time of the tube enlargement can be prevented from exceeding the proof stress (allowable stress) of the welds, the welded tubes can be adopted in a radiator in which the tubes (111) and the fins (112) are joined together mechanically by tube enlargement. As a result, the manufacturing cost of the tubes can be reduced in comparison with the case when seamless tubes are adopted as the tubes.

Abstract: An improved heat exchange apparatus for insertion in a housing comprises heat exchange tubes extending substantially parallel to a direction of fluid flow through the housing and a plurality of spaced and circumferential fins formed along the heat exchange tubes and extending substantially perpendicular to the direction of fluid flow through the housing. Preferably the housing is fit with a fluid mover for driving the fluid over the tubes. The improved heat exchanger can be applied in a method for extermination of pests comprising providing a minimal envelope, heating ambient air within the envelope using the improved heat exchanger and discharging the heated air into the envelope so that the temperature of air in the envelope is sufficiently high to kill pests. Moving air across steam filled tubes enables use of the system in explosion classified areas and without damage to goods or equipment.

Abstract: Heat exchange inefficiencies found in round tube plate fin heat exchangers are eliminated in an aluminum heat exchanger that includes first and second headers (20), (22) and at least one flattened tube (24), (70) extending between the headers (20), (22). A plurality of generally parallel tube runs are defined and each has opposite edges. A plurality of plate fins (26), (50) are arranged in a stack and each has a plurality of open ended slots (34), one for each run of the tubes (24), (70). Each of the tube runs (24), (70) is nested within corresponding slots (26) and the fins (26), (50) with one of the edges (40) of the tube runs extending outwardly of the corresponding fin (26). The assembly is brazed together.

Abstract: The present invention is directed to a thermosyphon heat exchanger. The thermosyphon system eliminates the need for costly and inefficient moving parts in the cooling system. The system also minimizes failures rendering the system inoperable by eliminating mechanical components subject to breakdowns that would render the system inoperable. The design of the heat exchanger coils provides for increased efficiency, reduced cost, and simplified construction and maintenance. The system further reduces the energy consumption required for cooling operation while still providing excellent cooling performance.

Abstract: In a single row evaporator coil having a last tube receiving refrigerant in a superheated condition, at least one baffle is provided to divert the flow of air passing over the superheat tube such that it also passes over a nonsuperheat tube so that air can be dehumidified by the cooling effect of the nonsuperheat tube prior to the air being passed downstream.

Abstract: A heat dissipating assembly (1) includes a plurality of fins (10), three heat pipes (20), and a base (30). Each fin defines three through holes (11) across a middle portion thereof. A plurality of dome-shaped protruding portions (14) is formed in each fin. The protruding portions are arranged in a regular array of offset rows. Adjacent protruding portions in any row protrude from front and rear faces of the fin in a regular alternating configuration. One end of each heat pipe is respectively inserted into the corresponding through holes of the fins, and an opposite end of each heat pipe is attached in the base. The base is attached on an electronic device, for absorbing heat produced by the electronic device. The protruding portions increase a heat dissipating surface area of the fins, and deflect airflow that passes across the fins in a direction parallel to the fins.

Abstract: A heat exchanger provided with tubes 210 through which a medium flows and tanks 300 to which the ends of the tubes are connected to perform heat exchange of the medium with heat conducted to the tubes, wherein the tanks each provided with an end plate 320 having holes 321 for connection of the ends of the tubes and a tank plate 310 to which the end plate is fitted; and when it is assumed that a cross section of the tank in its longitudinal direction has a passage area X and a total wetted perimeter length Y for the medium, they have a relationship of X=a·Y2/4&pgr; and 0.9≦a<1.0.

Abstract: A heat exchanger coil assembly is provided. The fins of the assembly include lance style enhancements on a corrugated shape of the fin. Lances are provided on both the upstream and the downstream sides of each corrugation. The upstream lance forms a first angle with respect to a direction of mean airflow and the downstream lance forms a second angle with respect to the direction of mean airflow. The first and second angles are not equal, such that the lances are canted with respect to one another. This generates two different streams of air flow such that a wake of the upstream lance will not impinge on the downstream lance, thereby maximizing heat transfer for both the upstream and the downstream lances.

Abstract: A heat exchanger, which is able to improve heat transmission function and reduce distances between fins to improve heat exchanging function and reduce a size by coating surfaces of the fins with certain materials to make condensate water attached on the surfaces of the fins discharged smoothly, comprises fins arranged with certain gaps therebetween to flow the air; and a tube, through which the fluid passes, installed to penetrate the fins, and the fins are arranged so that one surfaces treated by hydrophilic material and the other surfaces treated by water repellent material face each other with certain gaps therebetween.

Abstract: A heat sink includes a plurality of spaced laminas made of a thermally conductive material. Each of the laminas is integrally formed with a pair of convexo-concave spacers that each project from a first face of the lamina and define a cavity in a second face of the same lamina. Furthermore, each of the convexo-concave spacers is adapted to be partially and tightly fitted in a mating cavity of the next lamina.

Abstract: A fin tube heat exchanger. The fin tube heat exchanger comprises: a first tube row including a plurality of tubes; and a second tube row including a second plurality of tubes. The first and second tube rows includes a slab portion respectively in contiguous parallel relation with the counterpart slab portion of the other tube row. Each of the first and second tube rows includes a respective first and second spread portion wherein the first and second spread portions are in diverging non-contacting relation with respect to each other.

Abstract: A fin tube heat exchanger. The fin tube heat exchanger comprises: a first tube row including a plurality of tubes; and a second tube row including a second plurality of tubes. The first and second tube rows includes a slab portion respectively in contiguous parallel relation with the counterpart slab portion of the other tube row. Each of the first and second tube rows includes a respective first and second spread portion wherein the first and second spread portions are in diverging non-contacting relation with respect to each other.

Abstract: A finned-coil heat exchanger has a housing with spaced walls defining an internal chamber with air flowing from an upstream end to a downstream end, spaced transfer tubes with heat conducting media flowing therein from the downstream chamber end to the upstream chamber end, a series of spaced fins in contact with the tubes to transfer heat to flowing air, and a fan unit to move air through the exchanger. An air inlet is defined at the upstream end of the housing or in the lower end of one of the walls so that air can enter the internal chamber. The tubes each extend tortuously back and forth on a plane parallel to the direction of air flow so that there is a counterflow effect across the various segments of each tube. The tubes have at least six segments extending transversely across air flow with the tubes and fins being sized and spaced to provide for better air flow through the heat exchanger housing.

Abstract: A fin tube heat exchanger includes plate-shaped elongated fin members spaced at regular intervals, in parallel with one another. Each fin member has a fin base, through-holes in two rows in a longitudinal direction of the fin member, and raised portions with legs. Heat exchanger tubes are inserted into the through-holes. Each fin member has flat areas at a front and middle regions of a front half and a middle region of a rear half. The raised portion disposed at a rear region of the front half and a front region of the rear half has the legs inclined by a predetermined angle with respect to a traverse centerline which passes through the center of an adjacent through-hole of the front row. The distance from the centerline generally increases with a direction of airflow. A larger volume of air can be directed toward the vicinity of the tubes of the rear row. Each fin member has a front edge and a rear edge.

Abstract: An object of the present invention is to provide a heat exchanging fin capable of preventing cracks from forming in the flares of the collared tube holes, even if the metallic plate section is made of the thin and tough material. In the heat exchanging fin, a metallic plate section has a plurality of tube holes. A plurality of collars are respectively extended from edges of the tube holes. A plurality of flares are respectively formed at front ends of the collars. Each flare includes a plurality of radially extended sections, which are radially outwardly extended from the front end of each collar, and separation between the metallic plate section and each radially extended section is fixed.

Abstract: A method of manufacturing metal fins suitable for use in a heat exchanger which includes providing a coated patterned fin stock having a series of parallel stripes disposed longitudinally across the width of one surface of the fin stock. The stripe pattern is evenly spaced in the central portion of the fin stock, and staggered or more further spaced apart at the edges of said fin stock. The fin stock is passed through a series of forming dies to form or draw a plurality of tube receiving collared holes in the fin stock, followed by slitting or cutting the fin stock longitudinally to form a plurality of fin strips. The staggered spacing compensates for transverse movement of the fin stock during the drawing operation, and assures for accurate positioning of the collars between the fin stripes. The invention also includes the use of the fins in a high density coil design for use in a heat exchanger.

Abstract: The present invention relates to a heat exchanger in a refrigerator having, a simple structure and improved performance. The present invention includes refrigerant tubes for refrigerant flow, and a plurality of straight fins having lengths different from each other fitted to the refrigerant tubes at fixed intervals in parallel to each other by means of through holes formed therein, the heat exchanger having sections of different fin intervals, wherein a section with the smallest fin intervals has a size being 75% of a total size or less.

Abstract: The present invention discloses a heat exchanger fin having three rows of slit parts being arranged at the air inlet side and another three rows at the air outlet side relative to the centerline of heat transfer pipes 102, in order to reduce the ventilating resistance, prevent the growth of a boundary layer and reduce a dead zone on the downstream of the heat transfer pipes 102 to thus increase heat transfer performance. The outer slit parts 111 and 111′; and 116 and 116′ at the air inlet side and at the air outlet side are formed in pairs. The middle slit parts 112 and 112′ at the air inlet side are formed in pairs and the middle slit part 114 at the air outlet side is formed in a unit. The inner slit parts 113 and 114 at the air inlet side and at the air outlet side are also formed in a unit.

Abstract: A dog-bone type heat exchanger having a plurality of fin members for dissipating heat. Each of the plurality of fin members includes a pair of offset surfaces interconnected by a sloped interconnecting surface. The plurality of fins members may be spaced apart at a distance that is less than, equal to, or more than the offset distance between the pair of offset surfaces on each fin member, thereby maximizing the mixing of air flow and the conductive heat transfer of the heat exchanger through an impinging effect.

Abstract: A fin louver design using breaking and reversal louvers whose lengths are substantially longer than the half-length of the main louver but at slightly lower angles to the fin face, in order to increase the heat transfer while reducing or minimizing the airside air pressure drop. The reversal louvers will not dramatically change the airflow direction but rather permit air to follow the louver direction, thus preventing any dead area where the air speed is approximately zero in the central part between the two reversal louvers. Contact is provided between fresh moving air and the central part between the two reversal louvers.

Abstract: Welds (111a) are provided in areas that are offset from curved portions (111b) where stress concentration is likely to occur. This allows excess stress to be inhibited to occur at the welds at the time of tube enlargement. Therefore, even if the welds are softened and proof stress (mechanical strength) is reduced at the time of welding, as the stress occurring at the welds at the time of the tube enlargement can be prevented from exceeding the proof stress (allowable stress) of the welds, the welded tubes can be adopted in a radiator in which the tubes (111) and the fins (112) are joined together mechanically by tube enlargement. As a result, the manufacturing cost of the tubes can be reduced in comparison with the case when seamless tubes are adopted as the tubes.

Abstract: Disclosed is a fin and tube type heat-exchanger, which has a number of heat tubes of 6 mm or smaller to cause a reduction of the pressure loss and to prevent a drop in heat-exchange efficiency. Furthermore, the fin and tube type heat-exchanger can obtain the optimum heat-exchange efficiency, reduce the manufacturing cost and adapt to alternative refrigerants.

Abstract: Heat exchange surfaces are formed on a core object, by placing at least a part of a thermally conductive core object within a mold cavity that defines one or more heat exchange surfaces. A heated metal slurry such as, e.g., a magnesium alloy heated to a thixotropic state is injected under a predetermined pressure into the mold cavity. The heated metal slurry is then cooled to form a substantially continuous void free interface between the core object and the slurry when hardened.

Abstract: A new fin pattern of a ribbed vortex generator for use in an air conditioner or heat exchanger. It has multiple protruding turbulent prisms placed around a round tube on a radiation fin. Each protruding turbulent prism is strip rib-shaped 3D structure with one end higher and the other end lower. Each of the multiple protruding turbulent prisms is placed around the round tube at proper intervals, and oriented to the direction that fluid flows. The higher ends of a first pair of prisms are placed on the front end entrance of the round tube and the higher ends of a second pair of prisms are placed on the exit, which improves the heat transfer but causes little pressure drop-off.

Abstract: A micro-multi channel heat exchanger includes a lower header having a hollow for receiving refrigerant and an upper header opposite to the lower header. A plurality of tubes are arranged in a length direction of the upper and lower headers at fixed intervals, each having opposite ends fixed to the upper header and the lower header. A plurality of channels are formed in the tubes and elongated to be in communication with the hollows of the two headers. Each channel has an area of a section, parallel to a length direction of the two headers, reducing at a fixed ratio as the channels go from an air inlet side to an air outlet side. A plurality of fins are located between the tubes for heat exchange with the air.

Abstract: An improved heat exchange apparatus for insertion in a housing comprises heat exchange tubes extending substantially parallel to a direction of fluid flow through the housing and a plurality of spaced and circumferential fins formed along the heat exchange tubes and extending substantially perpendicular to the direction of fluid flow through the housing. Preferably the housing is fit with a fluid mover for driving the fluid over the tubes. The improved heat exchanger can be applied in a method for extermination of pests comprising providing a minimal envelope, heating ambient air within the envelope using the improved heat exchanger and discharging the heated air into the envelope so that the temperature of air in the envelope is sufficiently high to kill pests. Moving air across steam filled tubes enables use of the system in explosion classified areas and without damage to goods or equipment.

Abstract: A heat exchanger having refrigerant coil pipes connected in parallel is disclosed. The heat exchanger has a plurality of heat dissipating fins and a plurality of layers of refrigerant coil pipes which pass through the fins transversally. The plurality of refrigerant coil pipes are connected in parallel and then high pressure refrigerant driving by an air compressor is force into the refrigerant coil pipes. Air channels are formed between the refrigerant coil pipes and the fins.

Abstract: A heat exchanger fin collar for a plate-fin heat exchanger having close tolerance dimensions for achieving greater contact area on the tube. The fin collar comprises an elongated fin portion for dissipating heat and a leg connected with the fin portion. The leg has a height and includes a straight contact portion substantially perpendicular to the fin portion, wherein the contact portion has a contact height along which the contact portion contacts the tube. The height is in the range of 0.008 to 0.080 inches. It also includes a first curved end portion having a first radius extending from a first end of the contact portion and a stepped transitional portion connecting the contact portion and the elongated fin portion. The transitional portion has a second curved end portion having a second radius, wherein the second curved end portion extends from the contact portion opposite the first end. A method for forming the fin collar and a heat exchanger are also disclosed.

Abstract: In a heat transfer pipe, annular grooves in a direction inclined at an angle of 45° to 90° with respect to an axis of the pipe are continuously formed at an interval in a longitudinal direction of the pipe. The annular grooves desirably have a groove depth of 0.20 mm or more, and a groove pitch of two to five times larger than the groove depth. Moreover, a ratio W/P of a bottom width W of projections of the grooves to the groove pitch P is desirably 0.1 to 0.9.

Abstract: A fin for a heat exchanger coil assembly and a method of manufacturing the fin is provided. The fin includes a heat transfer enhancement pattern which appears sinusoidal in shape. The base wavy pattern of the enhancement pattern includes two wavelengths within each tube row and includes seven discrete segments. Six of the seven segments are circular arc segments. The seventh segment comprises two linear segments which form a condensate channel. The segments are arranged in a particular order at specific distances offset (above and below) from a leading edge nominal air streamline (LENAS) by a fraction of a nominal fin pitch Pf. The LENAS is related to the “normal” base wavy pattern used in other fins.

Abstract: A recess portion for setting an attachment position is formed in each plate fin at positions adjacent to both longitudinal ends of the plate fins on both upstream and downstream ends in an air flowing direction. Therefore, air passing through the plate fins is disturbed by a standing wall portion of the recess portion around the longitudinal ends of the plate fins. Thus, it can prevent a thermal boundary layer from being expanded in a heat exchanger having the plate fin, and heat-transmission efficiency can be improved in the heat exchanger. As a result, an entire area of the plate fin can be effectively used, thereby improving heat-exchanging capacity of the heat exchanger.

Abstract: An evaporator and method of making same includes a first end tank, a second end tank spaced from and opposing the first end tank, and a plurality of extruded fluid carrying tubes extending between and in fluid communication with the first end tank and the second end tank. The first end tank and the second end tank are formed as stampings.

Abstract: The wall thickness of at least a portion, which is plastically deformed, of a protruding portion used for calking is reduced to less than that of the other portions. Due to the foregoing, the bending rigidity of the protruding portion is decreased. Therefore, it is possible to bend (plastically deform) the protruding portion by a relatively low-intensity force. Accordingly, it is possible to easily execute the calking work (calking process) without the need to extend the length of the protruding portion (length from a forward end of the protruding portion to a bent portion). As a result, even if the pressure-withstanding property of an inter-cooler is enhanced by increasing the wall thickness of core plates, it is possible to prevent the calking workability from deteriorating and without increasing the size of the inter-cooler.

Abstract: Heat exchange inefficiencies found in round tube plate fin heat exchangers are eliminated in an aluminum heat exchanger that includes first and second headers (20), (22) and at least one flattened tube (24), (70) extending between the headers (20), (22). A plurality of generally parallel tube runs are defined and each has opposite edges. A plurality of plate fins (26), (50) are arranged in a stack and each has a plurality of open ended slots (34), one for each run of the tubes (24), (70). Each of the tube runs (24), (70) is nested within corresponding slots (26) and the fins (26), (50) with one of the edges (40) of the tube runs extending outwardly of the corresponding fin (26). The assembly is brazed together.