Abstract: The invention relates to a heat exchanger, especially for motor vehicles, which consists of a plurality of fins disposed in a parallel, spaced relationship, having openings and collars of oval or planar cross section adjoining the openings, and of a plurality of tubes of corresponding cross section disposed perpendicularly thereto and passing through the openings and collars. The tubes are joined to the fins by expanding their cross section after they have been inserted into the openings and collars thereby forcing their walls against the margins of the openings and collars.

Abstract: The present invention relates to a louvered heat transfer fin in which the air-passing resistance of the louver is varied so as to increase the overall heat exchange quantity, and thereby to greatly enhance the heat transfer performance of the fin. The arrangement of each louver is such that the projection area in the vicinity of the longitudinal central portion of the louver projected in the direction in which air passes is larger than the projection area of each of the longitudinal end sides of the louver projected in the same direction.

Abstract: The heat exchanger is formed of parallel rows of tubes and transverse ribs. The ribs have flat uncorrugated parts extending in zones about and along the rows of tubes as well as corrugated parts extending between the rows of tubes. The flat parts may be separated from the corrugated parts by stepped parts or fillers may be provided in the gaps between the uncorrugated parts. The gaps are to conduct a flow of medium in heat exchange relation to a flow of medium through the tubes. The crests and troughs of each corrugated part extend from the same plane adjacent a flat part and terminate in a similar plane at an adjacent flat part. Streamline-shaped inflow and outflow members aligned with the stepped part of the fin direct the flow of air.

Abstract: A sine-wave like plate fin for a finned tube heat exchanger coil is provided having an improved enhanced heat transfer area between adjacent pairs of holes in the plate fin. The enhanced heat transfer area includes a plurality of rows of triangular delta wings and ramp wings which generate counter rotating vortices to promote restarting or thinning of the hydrodynamic boundary layer and mixing the bulk fluid.

Abstract: A heat exchanger assembly of the side-entry cross-fin type includes first and second integral fin units, each comprising a single sheet of material provided with a plurality of aligned apertures, the sheet of material being folded in accordian-fashion such that the apertures define a plurality of notches arranged in rows which extend longitudinally of the fin unit. Two of the fin units are assembled together with a single length of heat exchange tube which threads the notches of the fin units, the tube extending over an oval-shaped helical path through the two fin units. In another embodiment, a single folded fin unit is provided with notches in fins on its upper and lower surface, a single length of tube being wrapped around the single fin unit threading the apertures therein, the tube extending in a generally oval-shaped helix path.

Abstract: A heat exchanger comprises a plurality of regularly corrugated fins placed one over another in layers at regular pitches in a back-to-back arrangement so as to form alternate wide and narrow fluid passage between the adjacent corrugated fins, and each having a plurality of small through holes, a plurality of collars formed in a staggered arrangement, and an annular area not having any small through hole and formed so as to surround the root of each collar; and pipes for passing a secondary fluid therethrough, each inserted through the collars of the layers of the corrugated fins. The height of the collar from the lower surface of the annular area corresponds to the pitch between the adjacent corrugated fins, and thereby the corrugated fins can be assembled at regular pitches simply by placing one over another. The pipes are expanded after being inserted through the collars so that the pipes are firmly and closely joined to the collars for satisfactory heat transmission between the fins and the pipes.

Abstract: A heat exchanger having replaceable heat exchange surfaces comprises a plurality of tubes formed into a bundle wherein the tubes are arranged linearly side by side. The heat exchanger is provided with a header and reverse header at either end of the tube bundle for directing the flow of fluid therethrough. A heat exchange structure is positionable about the tube bundle in thermal contact therewith. The heat exchange structure has a surface matrix from which extend a plurality of fins for receiving heat conducted from the tube bundle. The heat exchange structure may be conveniently formed into a U-shaped sleeve which may be slid over the tubes of the tube bundle and affixed in place by means of a thermal conductive cement. The tubes may be shaped to provide a streamlined flow of a cooling fluid about the fins thereby increasing the efficiency of heat transfer to the cooling fluid.

Abstract: A heat exchanger comprising fins and at least one heat transfer tube. An even number, not smaller than four, of louvers are severed and raised in an alternate and staggered manner with respect to a fin base line between the remaining adjacent fin base. Furthermore, the louvers raised on the same side with respect to the fin base line have heights defined by a line slanted at a constant angle in a stepped manner.

Abstract: A plurality of rows of circular openings for supporting water tube sections and turbulence fin arrays comprising plural vertically arrayed fin slots for guiding combustion gas to flow upwards at an angle therethrough are provided on each of a plurality of fin plates which are arrayed in parallel and disposed at the upper end of a water heater. The circular openings and the turbulence fin arrays of each row are alternately positioned. Therefore, each circular opening of a lower row is located below either of the turbulence fin arrays of a next higher row and each turbulence fin array of a lower row is located below either of said circular openings of a next higher row.

Abstract: The heat exchanger comprises tubes engaged into fins and tube plates connected to header boxes. The header boxes form on their smaller sides stirrups between the legs of which are defined inner edges on which are crimped the ends of platens formed by the tube plates. Moreover, the lugs of the side flanges are bent over on the sides of the stirrups.

Abstract: A heat exchanger core assembly having an improved tube-to-header joint construction wherein each individual tube end portion is preformed into a diamond-shaped configuration and each mating header plate is likewise preformed to include a plurality of diamond-shaped openings adaptable for receiving the corresponding diamond-shaped tube ends therethrough. Each tube member includes a body portion, a diamond-shaped end portion located at each opposite end thereof, and a gradual transition section which extends from each opposite end of the tube body portion to the respective diamond-shaped tube end portions. When mated together, each tube-to-header joint is bonded together such as by soldering or brazing. Each of the diamond-shaped openings in the mating header plates may also include an increased flange area extending at least partially therearound to improve the structural integrity and strength of the soldered or brazed joint between the tube end portions and the mating header plates.

Abstract: Heat exchanger having a tube plate made of plastic, in which metallic tubes are fixed. The tube plate has elevations having openings for accommodating the tube ends, with the openings being subdivided into three sections in axial extension. The center section has the smallest cross-section and the end sections are in each case widened. The elevations extend on both sides of the tube plate, the total height of the elevations located in the area of an opening, inclusive of the tube plate thickness, being about 1.8 to 2.5 times the single tube plate thickness.

Abstract: In this heat exchanger, an improvement comprises the following. The fin plates each have louvered portions interposing the aligned openings in the fin plates. The louvered portions in each fin plate define a nominal plane and include a plurality of louvers and a base. The base has base portions including rise portions and flank portions, three each. The rise portions and flank portions alternate with each other in a transverse direction across the width of the fin plate. The rise portions and flank portions form three peaks, which are a central peak and two outer peaks. The peaks are raised in a first direction perpendicular to the nominal plane. The rise portions and flank portions further form two valleys in the opposite, second direction perpendicular to the nominal plane. The valleys are spaced from each other and are each between the central peak and an outer peak. The rise portions are substantially parallel to each other and intersect the nominal plane at a first acute angle.

Abstract: Disclosed is a heat exchanger arranged such that a plurality of groups of cuttouts are formed on the surfaces of flat fins as between vertically adjacent heat transfer tubes by providing a plurality of cutouts, including two openings extending transverse to the direction of the air flow and two legs nonparallel with said direction of the air flow, on the front and reverse sides of the flat fins. This arrangement remarkably reduces the heat resistance between the air and the fin surfaces. Since the plurality of cutouts or the plurality of groups of cutouts are formed in the identical configuration, maintenance of a mold can be facilitated.

Abstract: Disclosed is a heat exchanger having a plurality of flat fins disposed in parallel at predetermined intervals and adapted such that the air flows therebetween and a plurality of heat-transfer tubes disposed to intersect at right angles with the plurality of fins and adapted such that a fluid flows therethrough. The heat-transfer tubes are arranged such that a line connecting the adjacent heat-transfer tubes in the longitudinal direction of the fin is perpendicular to the direction of the air flow. The projection area in the direction of the air flow of any of the heat-transfer tubes located on the upstream side with respect to the air flow partially overlaps the position of at least one of the heat-transfer tubes disposed on the downstream side thereof. The pitch of adjacent heat-transfer tubes is smaller in the direction perpendicular to the air flow than in the direction of the air flow. Such an arrangement excells in both the frosting characteristics and performance.

Abstract: A heat exchanger for the independent heating of the driver and front-seat passenger side of a passenger space, having flow pipes located at the ends of the heat exchanger at the transition between the upper and lower water compartment. These flow pipes are connected to the central flow connection via a flow channel transverse to the central flow connection and corresponding juncture channel. The transverse channel is located above a collecting chamber which is located at the lower side of the upper water compartment. The flow pipes guide the flow from the upper water compartment to the lower water compartment. Return pipes are positioned to guide the flow from the lower water compartment into the collecting chamber in the upper water compartment. From the collecting chamber the flow travels out of the upper water compartment through return connections.

Abstract: A fin-and-tube heat exchanger designed for one-way airflow, in which louvers, formed from the fin stock, progressively increase in length from the fin leading edge to its trailing edge. Their end walls channel air into stagnant air spaces behind the tubes. The tube collars may be offset somewhat toward the fin trailing edge, further reducing the stagnant air zones. In those bent heat exchangers in which air flows in from outside the curve, offsetting the collars also lessens the angular convergence of fin trailing edges inside the curve and presents less resistance to airflow.

Abstract: A generally corrugated fin of a finned tube heat exchanger is formed to have a plurality of cylindrical collars that fit closely around tubes containing a first fluid, for good thermally conductive contact therewith. The collars are arrayed in rows along the corrugations and, within each local fin region between adjacent collars, cuts are provided parallel to and between adjacent crests and troughs, with a portion of each crest locally inverted to form a local trough and each trough inverted to form a local crest between successive cuts. A second fluid flowing outside the tubes between adjacent fins is thereby enabled to form numerous short boundary layers and to flow from one side of each fin to the other, thereby promoting turbulence and flow-mixing that enhance heat transfer between the two fluids.

Abstract: A radiator comprising a plurality of longitudinally finned tubes formed from extruded aluminum and extending between upper and lower header pipes likewise of extruded aluminum. A water-tight joint is formed at the junction of each finned tube with the adjacent header by means of an interference fit nipple. The fins are shaped so as to define a gap between adjacent finned tubes through which air to be heated may be drawn. Such air enters a chamber defined between each adjacent pair of finned tubes and exits to the rear via louvers formed in the rear fins of the finned tubes, taking the general direction of arrows A. A degree of control of the heat output of the radiator may be achieved by rotation of a flap located at the bottom of the space between the radiator and the adjacent wall surface.

Abstract: A heat exchanger is provided in an air conditioner, refrigerator or the like, and is provided for the indirect transmission and reception of heat between fluids. The heat exchanger comprises a plurality of flat plate fins which are arranged parallel to one another at predetermined intervals so as to allow air stream to flow therebetween, and a plurality of heat transfer tubes passing through the flat plate fins for allowing a fluid to flow therethrough. Each fin is provided with a number of groups of air vents arranged to cross the wake side of the air stream. Each of the air vents is defined by a slat having four sides in which two sides, facing the air stream, are opened and other two sides are provided with leg portions for connecting the slat with the fin. The leg portions are aligned with each other and are inclined with respect to the normal line of the leading edge of the fin.

Abstract: An improved fin configuration is provided for use in central air conditioning unit heat exchangers in which heat transfer takes place between a first fluid, typically a refrigerant, flowing inside a nested plurality of tubes and a second fluid, typically air, flowing between the tubes and through a plurality of heat conducting fins attached to and arrayed between the tubes. Lanced pairs of streamwise adjacent bridge-like formations, one out each side of a generally corrugated fin surface, provide numerous leading edges to generate a plurality of reforming velocity and heat transfer boundary layers which leads to an increase in flow turbulence for enhanced heat transfer between the fins and the second fluid. By strategic location of a pair of such formations between tubes, with the upstream one of the pair at a positive angle of attack to the flow, air flow is directed through the fin to mix with flow on the other side of the fin and hence the heat transfer rate is improved.

Abstract: An air conditioner evaporator system that is interchangeable with existing automotive systems, and yet has substantial other uses, that employs an expandable liquid/gas media, such as freon, that is injected into a unique staggered coil arrangement, whereby the expanding gas travels through limited predetermined cycles only, before returning to the compressor for condensation and recycling; and wherein the exposed ends of the coils are insulated in a very facile way to preserve the refrigerating capability of the freon gas within the interior of the coils and simultaneously prevent sweating (condensation) on the exterior surface of the coils.

Abstract: An engine supercharger system has a heat exchanger cooling the supercharger air flow in response to supercharger pressure.

Abstract: A header of plastic material for a heat exchanger of the tube type has two identical faces provided with projecting ribs. The internal partition-wall of a water box is fitted between the ribs of one header face while the ribs of the other face are applied against an end fin of the tube bank.

Abstract: A plate-fin-tube type heat exchanger is constructed with a multitude of plate fins juxtaposed one another and a plurality of heat transmitting tubes passing through said plate fins and being held thereby. A plurality of cut and raised pieces are formed to intersect orthogonally with the air flowing direction at both front and rear surfaces of said plate fins with a certain space interval among them in the air flowing direction and at a location between the adjacent heat transmitting tubes arranged in the longitudinal direction of said plate fins, and then the edge portion on both sides of each cut and raised piece is re-bent in the direction opposite to the lifting direction of said piece and in substantially parallel with the surface of said plate fin so that the cross-section of said cut and raised piece may assume a sloping form in the direction of the air flow and that fin base plate portion may be present between the adjacent cut and raised pieces in parallel with the air flow.

Abstract: The purpose of this invention is to store hydrogen in the form of a metal hydride. The hydride is disposed on the surface of a plurality of metal fins which are attached to heat transfer tubes. The fins are closely spaced so that the weight of hydrogen stored per unit volume is high, approaching one pound per cubic foot. Because the formation of a metal hydride is quite exothermic, the rate of addition or removal of hydrogen to or from the hydride is limited by the ability of the apparatus to conduct heat to or from the hydride. The structure of the present invention provides for rapid heat transfer, so that the cell can be used in a heat pump, a hydrogen compressor, or to store hydrogen fuel for a vehicle. The invention includes embodiments wherein the heat transfer medium is either a liquid or a gas. The invention also comprises a new method of applying a metal or metal alloy, capable of forming a metal hydride, to a metal surface.

Abstract: A fin-and-tube type heat exchanger is disclosed in which the height of each raised, slotted louver from a fin base portion continuously changes in a direction crossing at right angles both the direction of the air flow and the direction of lamination of fins, and two or three kinds of such louver pairs, each consisting of louvers symmetric with each other with respect to the fin base portion, are arranged regularly.

Abstract: A plate fin heat exchanger including generally parallel rows of flattened tubes extending through a stack of generally parallel plate fins. Each of the plate fins is provided with generally H-shaped deformations with the H-shaped deformations being in rows which are staggered with respect to each other. The deformations increase the rigidity of the plate fins during tube pushing and act to induce turbulence in a fluid flowing through the heat exchanger to enhance heat transfer.

Abstract: A tube-and-plate heat exchanger comprising a plurality of plain tubes intended for a first heat carrier to pass through, which tubes are arranged in parallel rows and are received in broached holes of spaced plates. In cross section the plates are profiled so as to form, in the direction of flow of another, for example, a gaseous heat carrier, a continous symmetrically waved line, thereby forming a passage of undulatory shape for the gaseous heat carrier to flow through. Projections and depressions of each plate face corresponding projections and depressions of the other adjacent plate, thereby forming passages with alternating diverging-converging sections. The projections and the depressions of the cooled plates are made contiguous by rectilinear sections which each have an angle (.phi.) of inclination to the axis of symmetry of the cross-sectional wave line ranging from 8 to 45 deg.

Abstract: An evaporator comprising a plurality of heat transfer fins arranged mutually parallelly relative to the direction of air current and a multiplicity of louver boards formed by cuts inserted in substrates of said heat transfer fins perpendicularly to the direction of air current and sloped to prescribed angles from said substrates so as to be divided into a plurality of louver groups by the direction of sloping, which evaporator has the louver at the downstream zone of the fins in the direction of air current sloped so that the flow of the water condensate by gravity directs to the direction of an interior of the evaporator.

Abstract: An improved evaporator unit in which a cooling tube core is placed between guide panels which permit a portion of the refrigerated air band to by-pass the front air opening of the core and to thereafter be forced into the core along a substantial longitudinal length of one or more side air openings. The flow of an auxilliary portion of the air stream into the side air opening permits the diffusion of frost build-up within the cooling tube core. A heater is provided for use during a defrost cycle in order to add heat directly into the cooling tube core. The improved evaporator is designed for use with reverse flow air defrost refrigerated container apparatus. Use of the evaporator permits improved refrigeration and defrost cycle operation.

Abstract: Heat exchangers depend for efficiency upon optimum fluid flow, such as air, through their fins and about tubes extending through the fins. The air flow, particularly at the ends of a heat exchanger, can sometimes be of a significantly reduced amount owing to the construction of, or arrangement of elements in, the heat exchanger. First and second cores (12,14) of a heat exchanger (10) are positioned in a general "V" configuration with their inlet ends (24,42) adjacent one another. Apparatus (64) is provided upstream of the inlet ends (28,46) of the cores (12,14) to direct the air flow in a preselected orientation to inlet surfaces (20,38) of the cores (12,14) at the ends (28,46) of the cores (12,14). Air flow is thus improved over a portion of the heat exchanger (10) to increase its heat transfer efficiency.

Abstract: A motor vehicle heat exchanger for independently heating different passenger areas comprising first and second tube/fin block units for transferring heat from coolant flowing through tubes thereof to air flowing therethrough to first and second passenger areas, respectively. Common upper and lower coolant reservoir tanks supply coolant to both tube/fin units and receive coolant returning therefrom respectively. Intake tubes extend through a common gap between the first and second tube/fin units to supply heated coolant to the lower cooling tank.

Abstract: A heat exchanger such as a radiator for an automotive engine is produced by fixing lengths of flattened tubes and corrugated fins to each other by brazing within a furnace. The flattened tube is formed by bending a strip and welding the opposing edges of the bent strip to each other to form a tube of a substantially circular cross-section, and applying pressure to the tube along the weld line to form the flattened tube while depressing the tube wall along the weld line to form an elongated recess or groove along the weld line. Then, a brazing material is applied to the outer surfaces of the flattened tube to cover and fill up any minute weld defects which may exist in the flattened tube whereby the weld defects are repaired.

Abstract: An improved louver pattern for fins of a tube and fin type heat exchanger, in which groups of louvers are formed radially with respect to the tubes, extending from each tube to adjacent tubes. Each louver group consists of a plurality of parallel slits in the fin extending in the radial direction, and defining elongate rectangular portions of the fin therebetween, which are twisted at an angle to form inclined louvers in an otherwise generally planar fin. The louver groups thus formed provide improved turbulence and mixing to break up the viscous or boundary layer of flow across the fin, and to create turbulence and vorticity to further improve mixing of the fluid and heat transfer.

Abstract: A single inlet/outlet-tank U-shaped tube heat exchanger is disclosed comprising a tank having a header plate and a plurality of U-shaped tubes whose legs extend through and terminate with an open end at one side of the header plate. A first group of the tubes is arranged so that the two open ends of each of these tubes are located in one and the other of two outboard rows extending longitudinally of the header plate. A second group of the tubes with a smaller radius return bend is arranged in staggered pairs intermediate those in the first group and with their return bends parallel to each other and angled to those in the first group so that one open leg end of each of the tubes in the second group is located in one and the other of the outboard rows and the remaining open leg end of each of these tubes is located in a third and inboard row extending between the two outboard rows.

Abstract: A solderless type automotive engine radiator has upper and lower tanks and a heat exchanger core connected at the upper and lower ends to the tanks through upper and lower header plates. The core is formed by tubes and fins secured to the tubes without soldering. The upper and lower ends of the tubes are in gripping engagement with inner peripheral surfaces of holes formed in the header plates. Layers of adhesive are formed on the surfaces of the header plates adjacent to the core to form liquid-tight seals between the header plates and the tubes. The adhesive layers and the fins are arranged such that at least the fin nearest to an adjacent adhesive layer is either in face-to-face engagement with the adjacent adhesive layer or embedded in the adjacent adhesive layer to strengthen the adhesive layer and protect the same against foreign materials such as water and dirt whereby the durability of the seals is improved.

Abstract: Heat exchangers depend for efficiency upon maximizing fluid flow, such as air, through their fins about tubes extending through the fins. The air flow, particularly at the ends of a heat exchanger, can sometimes be of a significantly reduced amount owing to flow restrictions caused by the construction of, or arrangement of elements in, a heat exchanger. A core (12) of a heat exchanger (10) of the present invention utilizes a relatively varied angular arrangement for tubes (16) in the core (12) which improves air flow, particularly at the ends (28,40) of the core (12). Air flow is thus improved over a portion of the heat exchanger (10) to increase heat transfer, as well as purging of debris, for the folded or zipzag core arrangement described.

Abstract: A single inlet/outlet-tank U-shaped tube heat exchanger is disclosed comprising a tank having a header plate and a plurality of U-shaped tubes whose legs extend through and terminate with an open end at one side of the header plate. A first group of the tubes is arranged so that the two open ends of each of these tubes are located in one and the other of two outboard rows extending longitudinally of the header plate. A second and remaining group of the tubes is arranged so that the return bends of these tubes criss-cross those of alternate tubes in the first group and have their open leg ends all located in a third and inboard row extending between the two outboard rows.

Abstract: A joint construction for a fin-and-tube type heat exchanger formed of aluminum suitable for use as an evaporator of a cooling system for an automotive vehicle, wherein an end plate near the open ends of tubes is formed with openings larger in diameter than the openings formed in fins to which the tubes are securedly fixed. The joint construction includes a flare formed at the open end of the tube by inserting a tube end flaring punch and restrained by the opening formed in the end plate to be kept from outwardly expanding more than is necessary. Thus the flare produced has high dimensional accuracy and a tube member can be joined to the open end of each tube by brazing with a high degree of accuracy and precision. The brazed joint produced has higher reliability in performance than brazed joints of the prior art. The use of the improved joint construction enables brazing to be carried out automatically and allows a compact size to be obtained in a fin-and-tube type heat exchanger.

Abstract: A fin element for a heat exchanger has alternate fins A and B in parallel planes in a longitudinal central zone 10. Edge zones 12 are bent at obtuse included angles with respect to the parallel planes. The fin element is formed from a metallic strip of material by pressing the fins A and B in opposite directions and allowing the overall width of the strip to reduce so that the finished element has a constant thickness.

Abstract: Disclosed is a heat exchanger, preferably for use in automotive vehicles, comprising a plurality of parallel tubes and a plurality of ribs extending the tubes, together with lateral parts fastened to the ends of the ribs. According to the invention, the lateral part consists of a strip applied against the ends of the ribs and joined with the ribs by means of an adhesive or by the embedding of the rib ends into the material of the strip. Also disclosed is a process for the manufacture of heat exchangers of this type.

Abstract: An air to air heat exchanger maximizes the space that is available for cooling process air while keeping the pressure drop of the process air through the heat exchanger at a minimum and at the same time utilizes easily available components for manufacture. A pair of headers are provided in the air to air heat exchanger and the headers are connected with a plurality of tubes arranged in a triple tube arrangement such that there are a plurality of sets of three tubes in each set. The sets of tubes are spaced along the length of the headers. Each of the tubes are bent into an "S" shape so each tube has three lengths or sections extending from side to side of the heat exchanger between the input header and output header.

Abstract: A heat exchanger with at least one main tube, closed off at one end, into which compressed air, which is to be heated, is admitted and, after being heated, is removed. The main tube has at least two channel guideways which are separated from one another in the longitudinal direction. U-shaped or curved compressed air lines project from the main tube and contact the hot gases. Each compressed air line is connected at one end to the channel guideway of the main tube into which compressed air is admitted, and at its other end with the channel guideway through which the heated compressed air is removed. The compressed air lines are formed primarily from hollow bodies, which extend in the direction of flow of the hot gas and which preferably are tapered at the inflow and outflow ends in order to aid the flow.

Abstract: A heat exchanger fin according to the invention has a multiplicity of fins arranged substantially in parallel with the direction of air flow and at least one heat transfer tube to which said fins are connected in a heat conducting relation. A multiplicity of louvers inclined by a small angle to the direction of air flow are formed in said fins.According to this construction, it is possible that the air as a whole can flow substantially straight across the heat exchanger and can strongly collide with all louvers, thereby to ensure a reduced flow resistance encountered by the air flow, as well as improved heat transfer performance of the heat exchanger.

Abstract: A radiator for motor vehicles is provided which has several tubes opening to respective upper and lower radiator tanks and arranged parallel to one another for the guidance of heat exchange fluid. Heat exchange fins are disposed perpendicularly to the tubes and are fixedly connected thereto. The fins exhibit respective cut-out openings forming a groove at at least one of the surfaces of the fin blocks, which groove expands toward the inside and serves for connecting lateral parts, which lateral parts grip with tabs into the groove formed by the cut-outs. Each lateral part is formed of two halves which are pivotally connected with one another along an axis running in the direction of the groove and which are provided with tabs which extend outwardly over the lateral edges of the halves into the groove and abut the fins on the lateral walls of the groove. To form a rigid or stiff connection between the lateral part halves after their installation in the groove, locking or closing elements are provided.

Abstract: A plate floor heat exchanger has a plurality of conductive mutually parallel plates spaced apart by narrow gaps defined by spacer bands which can have a streamlined shape and each of which are traversed by a plurality of tubes extending perpendicular to the plates. The spaces between longitudinal edges of these bands define flow channels for a fluid in a heat exchange relationship with the fluid traversing the tubes.

Abstract: A method and apparatus for appropriately deforming the tube extensions projecting beyond the tube sheet is disclosed. The excess extension material is rolled backwardly toward the tube sheet and slit to prevent catastrophic failure of the extension such that the tube extensions are all configured to extend equidistantly from the tube sheet notwithstanding the fact that they extended various distances depending upon the irregularities of the expansion process. The tooling includes a cylindrical tool having portions for rolling material back towards the tube sheet and spaced teeth for slitting the material to relieve any potential for catastrophic failure.

Abstract: An improved fin element adapted for use in a fin and tube type heat exchanger core assembly, the improved fin element having a plurality of tube openings extending therethrough and having a "dog-bone" type pattern of corrugations extending substantially over the entire planar surface thereof, the corrugated pattern forming a uniform, discontinuous, six-sided configuration about each respective tube opening for altering the fluid flow characteristics across the fin in such a manner as to enhance its heat transfer capability. The particular pattern of corrugations utilized on the subject fin element effectively induces turbulent flow thereacross; it causes circulation of the fluid medium flowing thereacross to the downstream side of the tubes extending therethrough; and, it effectively reduces the thickness of the boundary layer associated therewith to achieve increased heat transfer performance without a corresponding increase in fluid flow resistance.

Abstract: Tube circuits for heat exchangers which provide same-end inlet and outlet connections are disclosed, in which each circuit includes conduits of two types. In a preferred embodiment, the first type conduit has two tubes and is generally U-shaped, and the second type conduit has four tubes. The inlets for each conduit are disposed adjacent each other in the assembled heat exchanger, as are the outlets for the conduits. To equalize flow and pressure drop a turbulence promoting device can be disposed in the U-shaped conduit. The circuits can be used for providing same-end connections on coils previously available only in opposite end connection configurations, such as for example, three-row full-circuited and six-row double circuited coils.