HEAT EXCHANGER MODULE FOR A VEHICLE OR THE LIKE

Abstract: A heat exchanger module particularly suited for vehicular appli­ cation includes at least two adjacent heat exchangers (12, 14). At least one of the heat exchangers has a side defined by an outwardly opening channel (30, 32) which in turn receives a plastic bar or strip (18, 20). The bar is provided with a plurality of relatively deep recesses (70) which are alignable with holes (40) in the channel. The bottoms of the recesses are sufficiently thin as to be easily penetrable by a threaded fastener extending through the holes in the channel and into the recesses for securing components of the module together and yet are sufficiently thick as to prevent the flow of fluid through the recesses to thereby assure that heat exchange fluid will pass through the heat exchangers.

Description: This invention relates to a heat exchanger module comprising at least two metallic heat exchangers. The last several years has seen an increasing number of heat exchangers employed in vehicles. One heat exchange fluid is the air in which the vehicle is moving which is commonly ducted through a grill or the like to pass through the heat exchanger with assistance from a fan driven either by the engine or by a small electric motor. In the early days of vehicles, liquid cooled engines required only a single heat exchanger of the type alluded to previously. As is well known, they were commonly termed radiators and were utilized for cooling the liquid coolant for the engine. As the complexity of vehicles increased, other air cooled heat exchangers were added. Frequently, the provision of an automatic transmission requires a so-called oil cooler as a second form of heat exchanger. The increasing use of air conditioning in vehicles has necessitated that such vehicles have additional air cooled heat exchangers in the form of condensers. And, with the increased use of turbochargers, there has been an increasing move towards the use of so-called intercoolers or charge air coolers which are heat exchangers that cool compressed combustion air from the turbocharger prior to its being admitted into the engine combustion chamber or chambers. Constraints on vehicle fuel economy have led to constraints on vehicle size which in turn have led to constraints on the amount of grill area available on a car that may be occupied by the heat exchangers. Consequently, it is necessary to superimpose heat exchangers or dispose them in side-by-side relationship, or both. This leads to difficulty in installation during manufacture as well as to difficulty in achieving access to a given one of the heat exchangers in the event repair or other attention is required. In US-A-4137982 there is disclosed a pair of heat exchangers disposed in side-by-side relation. One of the heat exchangers comprises an engine fluid cooling core and the other heat exchanger comprises an implement fluid cooling core. The engine cooling core is relatively non-rigid and is reinforced by being releasably secured in a steel frame by bolts. The steel frame includes upper and lower face plates interconnected by side plates which extend along each side of the engine cooling core. The bolts extend through the side plates for securing the engine cooling core within the steel frame. One of the side plates abuts the adjacent side of the implement fluid cooling core which is substantially rigid usually being constructed of steel and thus not requiring a reinforcing frame. Thus, that side plate spaces the two heat exchangers, that is to say the engine fluid and implement fluid cooling cores, in non-contacting relation, and takes the form of an elongated bar. Further, that side plate in conjunction with the bolts which, of course, are fasteners having shanks form part of means mounting the heat exchangers to each other in spaced non-contacting relation. Such mounting means is completed by a pair of connector bars, each preferably of steel, which respectively extend along the tops and bottoms of the side-by-side heat exchangers and are bolted thereto, thereby securing the heat exchangers together. More precisely, the top connector bar is mounted against and bolted to the top of the implement fluid cooling core and further mounted against and bolted to the upper face plate of the steel frame rigifying the engine fluid cooling core. The bottom connector bar is mounted against and bolted to the bottom of the implement fluid cooling core and further mounted against and bolted to the lower face plate of the same steel frame. Thus, either of the cores can be removed from or installed into the vehicle independently of the other, or both cores can be removed from or installed simultaneously. Whilst the heat exchange module of US-A-4137982 provides a solution to the problem of mounting heat exchangers in side-by-side relation, the means by which it does so suffers from certain disadvantages. Thus, although the top and bottom connector bars can be selectively mounted to and demounted from the respective heat exchangers so that the heat exchangers may be independently or simultaneously removed for replacement or repair, because the bars are made of steel the holes in them receiving the bolt must be pre-formed and at defined centres coinciding with the holes which would also be preformed in the heat exchangers and through which the bolt shanks would be passed. Accordingly, no compensation is provided for lack of alignment in the various components which could give rise to difficulties in the assembly process. Moreover, where heat exchangers are made of metal components, contact between different ones of the heat exchangers should be avoided to prevent the passage of galvanic currents between them with the attendant risk of galvanic corrosion. In the heat exchange module of US-A-4137982, the side-by-side metallic heat exchangers are not only in such contact with each other via the steel frame reinforcing the engine cooling core but also physically joined by the top and bottom steel connector bars. In accordance with the present invention as claimed, a heat exchange module comprises at least two metallic heat exchangers and means mounting the heat exchangers in spaced non-contacting relation including fasteners having shanks and an elongated bar of plastic material, the bar having a series of recesses along its length, each recess having a closed bottom of sufficient thickness to prevent the flow of fluid through the recess and of sufficient thinness to be easily penetrable by the fasteners, the recesses being oversize in relation to the size of the shanks, each fastener extending through an associated one of the heat exchangers and penetrating the bottom of one of the recesses. With such a heat exchange module constructed in accordance with the present invention, a plurality of heat exchangers can readily be mounted in side-by-side relationship, and readily removed for repair or other attention. Thus, in one preferred embodiment of the invention, there is a pair of the heat exchangers in side-by-side, but spaced relation; each of the heat exchangers, at their point of adjacency, has an elongated, shallow channel facing the other heat exchanger, the side walls of each channel including aligned, apertured tabs with the tabs on one channel being staggered with respect to the tabs on the other channel; the elongated plastic bar is received in and spaces the channels, the bar having at least one row of the recesses opening towards the side walls of the channels, at least some of the recesses aligning with the apertures in the tabs, the bottoms of the recesses being sufficiently thin so as to be easily penetrable by the shank of a fastener and of sufficient thickness as to prevent the flow of fluid through the interface of the heat exchangers; and the fasteners shanks which are of smaller size than the recess extend through the apertures and the aligned recesses to secure the heat exchangers to each other via the plastic bar. A plurality of heat exchangers can readily be mounted in superimposed relationship using a heat exchange module constructed in accordance with the present invention. In such an arrangement comprising another preferred embodiment of the invention, the heat exchangers comprise first and second superimposed heat exchangers; one of the first and second heat exchangers has opposed sides defined by outwardly open channels, the sides of the channels including aligned apertures adapted to receive the shank of a fastener, a said elongated plastic bar is disposed in each channel and extends out of the same in the direction away from the heat exchanger, each bar having at least one row of elongated recesses, at least some of which are alignable with the apertures in the channels; apertured legs on the other of the heat exchangers space the same from said one heat exchanger and engage the bars in alignment with some of the recesses and in spaced relation to the channels; first ones of the fasteners penetrate the apertures in the channels and the aligned recesses to secure the bars to said one heat exchanger; and second ones of the fasteners penetrate the apertures in the legs and the aligned recesses to secure the other heat exchanger to the bars and thus to said one heat exchanger. A heat exchange module comprising both side-by-side and superimposed heat exchangers may be provided by said one preferred embodiment of the invention having the remote sides of the heat exchangers provided with additional ones of the channels and with additional plastic bars received in the additional channels; and which further includes a third heat exchanger in superimposed relation to, but spaced from, the pair of side-by-side heat exchangers, the third heat exchanger including apertured legs abutting the additional bars spaced in relation to the sides of the additional channels and additional fasteners impaling the legs to the additional bars. One advantage of the present invention is that by suitably dimensioning and positioning the recesses along the length of the elongated bar, such bars can be used in conjunction with the fasteners and with the apertured legs to mount heat exchangers as described in the aforesaid preferred embodiments thereby providing the degree of mounting flexibility required, i.e. heat exchangers in side-by-side relationship, superimposed relationship, or both. Another advantage is that by making the plastic bar with a series of oversized recesses relative to the size of the fasteners shanks and with the bottom of each recess closed but of sufficient thinness to be easily penetrable by the fastener shanks, considerable misalignment of the various components can be compensated for without difficulty. A further advantage is that because the plastic bar constitutes an insulator and mounts the heat exchangers in spaced, non-contacting relation, any possibility of galvanic corrosion is obviated. Attention is also drawn to US-A-3938587 which discloses a tension fastener for quickmounting an oil cooler in stacked relationship on one side of the radiator or condenser in an automotive or other engine system. In order that the invention may be well understood there will now be described an embodiment thereof, given by way of example, reference being had to the accompanying drawings, in which: Fig. 1 is an exploded view of a heat exchanger module, including a fan shroud, made according to the invention; Fig. 2 is a fragmentary, enlarged plan view of the same module with parts broken away for clarity; Fig. 3 is an enlarged, fragmentary elevation of the same module; Fig. 4 is an enlarged, fragmentary view of a strip or bar employed in the same module; and Fig. 5 is an enlarged, horizontal section of the bar or strip taken approximately along the line 5-5 in Fig. 3. The exemplary embodiment of the invention is illustrated in the drawings in the form of a heat exchanger module intended for vehicular applications. However, it is to be understood that the module may be utilized in other, non-vehicular applications where plural heat exchangers may be necessitated and it is desirable to provide for ease of manufacture and ease of maintenance or repair. As illustrated in Fig. 1, there is illustrated a fan shroud, generally designated 10, which may or may not be part of the heat exchanger module. In the usual case, it will not be part of the module but will be fabricated so as to cooperate therewith. The module may also include a first heat exchanger, generally designated 12. In a vehicular application, the heat exchanger 12 will typically be a radiator. A second heat exchanger, generally designated 14, is also included. The exchanger 14 in a vehicular application will conventionally be a so-called oil cooler. The heat exchanger 14 and the heat exchanger 12 are in side by side, but spaced relation as will more fully hereinafter appear. Superimposed on the heat exchangers 12 and 14 is a third heat exchanger, generally designated 16. As illustrated, the heat exchanger 16 may be a parallel flow condenser for use in the air conditioning system of a vehicle. The module is completed by securing strips or bars, one form of which is generally designated 18 and another form of which is generally designated 20. The bar 18 is used in connection with fasteners (not shown) to secure the heat exchangers 12 and 14 in side by side, but spaced relation. The bars 20 are utilized to secure the heat exchanger 16 to the assembled heat exchangers 12 and 14 or, simply to the heat exchanger 12 if the oil cooler 14 is omitted. In addition, the bars 20 are employed for securing the fan shroud 10 to the assembly of heat exchangers defining the module. Referring to the construction of the heat exchangers 12 and 14, the same are generally identical as far as the present invention is concerned, it being understood that their capacities and heat exchange capabilities may differ depending upon the application to which they are put. Each includes an upper header 22 and a lower header 24. A plurality of tubes 26 extend between the headers 22 and 24 and adjacent tubes 26 are interconnected by serpentine fins 28 as is well known. Opposed sides of the heat exchangers 12 and 14 are defined by relatively shallow, elongated channels 30 and 32. The ends of the channels are partially closed by tabs 34 extending outwardly from the associated header 22 or 24. The bars 18 and 20 are sized to be snugly received within the channels between the tabs 34 and to extend out of the channels in the direction away from the channel bottom, that is, away from the heat exchanger of which the channel is a part. Each side wall 36 of each of the channels 30 and 32 includes outwardly extending tabs 38 and corresponding tabs 38 have aligned apertures 40. As can be seen in Figs. 1 and 3, the tabs 38 on the heat exchanger 12 adjacent the heat exchanger 14 are staggered with respect to the tabs 38 on the heat exchanger 14 adjacent the heat exchanger 12. As best seen in Fig. 3, this allows the heat exchangers to be disposed in close side by side relation without contact between the two. In this connection, particularly where the heat exchangers are conventionally made of metal components, contact between different ones of the heat exchangers is to be avoided to prevent the possibility of galvanic corrosion. To this end, the bars or strips 18 and 20 are made of an insulating material. The use of an insulating material prevents the passage of galvanic currents between the adjacent or superimposed heat exchangers and thereby prevents galvanic corrosion from occurring. Any insulating material may be utilized but preferably, the same is a plastic which is not brittle and which is capable of withstanding the heat that may be imparted thereto through passage of the fluids to be cooled through the respective heat exchangers. Glass filled nylon as conventionally used in plastic tanks for radiators is but a single example of a plastic that may be used satisfactorily. The heat exchanger 16 may include tubular headers 50 and 52 between which tubes 54 extend. Again, serpentine fins 56 extend between the tubes 54. The header 50 mounts two spaced legs 58 each having a base 60 provided with an aperture 62. The header 52 also mounts two of the legs 58 which are provided with the apertures 62. As best seen in Fig. 2, the bases 60 of the legs 58 are so located with respect to the body of the heat exchanger 16 as to cause a space 62 to exist between the heat exchanger 16 on the one hand and the heat exchangers 12 and 14 on the other. In the case of each of the heat exchangers 12, 14, and 16, the location of inlet and outlet ports has been omitted since it is well within the skill of the art to locate the same wherever most desirable in a given system. Turning now to Figs. 4 and 5, the bars 18 and 20 will be described in detail. Only the bar 20 is illustrated in these figures, it being understood that the bar 18 may be identical to the bar 20 save for the differences that will be mentioned. Each of the bars 20 includes a plurality of oblong, deep recesses 70. The recesses 70 are aligned and are in two rows shown at A and B in Fig. 4. The bar 18 will have but a single one of the rows and typically will be narrower than the bar 20. Turning to Fig. 5, each of the recesses 70 has a bottom 72. In the preferred embodiment, for ease of molding, the recesses 70 open to but a single side of the bar 20, which will be one of the sides facing a side wall 36 of one of the channels 30 and 32. In such a case, the bottom 72 will be on the opposite side of the bar 20. In order to assure that all air flowing through the module is channeled through the areas containing the various tubes and serpentine fins for maximum heat transfer efficiency, the bottoms 72 are provided in the recesses. They are made sufficiently thick as to prevent air flow through the bars 18 and 20. That is to say, in the case of a vehicular installation, they are made of sufficient thickness as to withstand ram air pressures at the maximum speed contemplated for the vehicle. At the same time, they are made sufficiently thin so as to be easily penetrable by the shank of a fastener as, for example, a conventional threaded fastener. In the usual case, the thickness of the bottom 72 may be as little as 2 or 3 mils. As mentioned previously, the recesses 70 are elongated and in particular, are elongated in the direction transverse to the direction of elongation of the associated bar 18 or 20. In addition, as can be seen in Fig. 2, the same are made oversize with respect to the size of the shank of a threaded fastener that may be employed to secure the assemblage together. The recesses are further nominally centered in alignment with the apertures 40 in the various tabs 38 as well as the apertures 62 in the legs 58. To provide maximum flexibility in the use of the bars 18 and 20, they will typically contain many more of the recesses 70 than would be required for a given installation, thus allowing the bars to be used in several differing installations that may have different alignment of the various components. Furthermore, the use of plural ones of the recesses 70 minimizes the weight of the respective bar 18 and 20 and attains a material savings as well. In any event, headed, threaded fasteners having shanks 80 and heads 82 are passed through aligned ones of the apertures 40 in the channels 30 and 32 at the interface of the heat exchangers 12 and 14 and through the bottoms 72 to receive speed nuts 84 and thereby secure any heat exchangers 12 and 14 in side by side relation. Because the recesses 70 are elongated and oversize with respect to the size of the shanks 80 of the fasteners, considerable misalignment will be accommodated with little difficulty. Identical fasteners having shanks 80 and heads 82 are passed through the apertures 40 in each of the channels 30 and 32 receiving one of the bars 20 to each receive a speed nut 84. This construction secures the bars 20 to the assembled heat exchangers 12 and 14. It will be observed in Fig. 2 that this set of fasteners extends through the row of recesses 70 nearest to the associated heat exchanger. Additional fasteners having shanks 80 and heads 82 extend through apertures 85 (Fig. 1) aligned with the apertures 62 and the legs 58 and located in the periphery of the shroud 10 to receive speed nuts 84. Thus, such fasteners serve to secure the heat exchanger 16 to the heat exchangers 12 and 14 via the bars 20. They serve the additional function of mounting the heat exchanger module to the fan shroud 10 about its periphery such that all air passing through the module must pass through the same between the various tubes of the various heat exchangers in heat exchange relation with the associated fins. From the foregoing, it will be appreciated that a module made according to the invention is readily assembled during the manufacturing process. Very little effort is required to force the various threaded fasteners through the bottoms 72 of the grooves 70 and yet such bottoms are sufficiently thick to prevent short circuiting flow of cooling air, that is, prevent the flow of cooling air in paths that are not in heat exchange relationship with the fins of the various heat exchangers. The unique arrangement of the bars 18 and 20 further allows excellent compensation for lack of alignment in the various components while providing a means for economical cost for securing the components together in electrical isolation to prevent galvanic corrosion. It will also be observed that in the embodiment specifically disclosed, a total of eight fasteners interconnect three heat exchangers and a fan shroud. As a consequence, it will be appreciated that the module may be easily and readily disassembled for repair and/or maintenance of one or more of its components.

Claims: A heat exchanger module comprising at least two metallic heat exchangers (12, 14, 16) and means mounting the heat exchangers in spaced, non-contacting relation including fasteners having shanks (80) and an elongated bar (18; 20) of plastic material, the bar having a series of recesses (70) along its length, each recess having a closed bottom (72) of sufficient thickness to prevent the flow of fluid through the recess and of sufficient thinness as to be easily penetrable by the fasteners, the recesses being oversize in relation to the size of the shanks, each fastener extending through an associated one of the heat exchangers and penetrating the bottom of one of the recesses. A heat exchanger module as claimed in claim 1, wherein the recesses (70) are elongated in a direction transverse to the direction of elongation of the bar (18; 20). A heat exchanger module as claimed in claim 1 or claim 2, wherein the recesses (70) open to a single side of the plastic bar (18; 20). A heat exchanger module as claimed in any of the preceding claims, wherein the recesses (70) are aligned in a single row (A; B). A heat exchanger module as claimed in any of claims 1 to 3, wherein the recesses (70) are aligned in plural rows (A, B). A heat exchanger module as claimed in any of the preceding claims, wherein at least one of the heat exchangers (12, 14) includes a side defined by an outwardly opening channel (30; 32) with opposed side walls (36), the plastic bar (18; 20) being snugly received in the channel and the associated fasteners having their shanks (80) extending through each of the side walls as well as the bar. A heat exchanger module as claimed in any of claims 1 to 3, wherein there is a pair of the heat exchangers (12, 14) in side-by-side, but spaced relation; each of the heat exchangers, at their point of adjacency, has an elongated, shallow channel (30, 32) facing the other heat exchanger, the side walls (36) of each channel including aligned, apertured tabs (38, 40) with the tabs on one channel being staggered with respect to the tabs on the other channel; the elongated plastic bar (18) is received in and spaces the channels, the bar having at least one row (A; B) of the recesses (70) opening towards the side walls of the channels, at least some of the recesses aligning with the apertures (40) in the tabs, the bottoms (72) of the recesses being sufficiently thin so as to be easily penetrable by the shank (80) of a fastener and of sufficient thickness as to prevent the flow of fluid through the interface of the heat exchangers; and the fasteners shanks which are of smaller size than the recess extend through the apertures and the aligned recesses to secure the heat exchangers to each other via the plastic bar. A heat exchanger module as claimed in claim 7, wherein the remote sides of the heat exchangers (12, 14) are provided with additional ones of the channels (30, 32) and additional plastic bars (20) are received in the additional channels; and which further includes a third heat exchanger (16) in superimposed relation to, but spaced from the pair (12, 14), the third heat exchanger including apertured legs (58) abutting the additional bars in spaced relation to the sides of the additional channels and additional fasteners impaling the legs to the additional bars. A heat exchanger module as claimed in claim 8, further including a fan shroud (10) in superimposed relation to the heat exchangers (12, 14, 16), the additional fasteners additionally impaling the fan shroud. A heat exchanger module as claimed in any of claims 1 to 3, wherein the heat exchangers (12, 14, 16) comprise a first and second superimposed heat exchanger (12, 14; 16); one (12; 14) of the first and second heat exchangers has opposed sides defined by outwardly opening channels (30, 32), the sides (36) of the channels including aligned apertures (40) adapted to receive the shank (80) of a fastener; a said elongated plastic bar (20) is disposed in each channel and extends out of the same in the direction away from the heat exchanger, each bar having at least one row (A; B) of the recesses (70), at least some of which are alignable with the apertures in the channels; apertured legs (58) on the other (16) of the heat exchangers space the same from said one heat exchanger and engage the bars in alignment with some of the recesses and in spaced relation to the channels; first ones of the fasteners penetrate the apertures in the channels and the aligned recesses to secure the bars to said one heat exchanger; and second ones of the fasteners penetrate the apertures in the legs and the aligned recesses to secure said other heat exchanger to the bars and thus to said one heat exchanger. A heat exchanger module as claimed in claim 10, further including a fan shroud (10) superimposed on said other heat exchanger (16) and having apertures (85) aligned with the apertures (60) in the legs (58), the second fasteners additionally securing the fan shroud to the plastic bars (20).

Inventors: COSTELLO, NORMAN FRANCIS, GRANETZKE, DENNIS CLARE, STRUSS, RODNEY A.
Applicants: MODINE MANUFACTURING COMPANY
Application year: 1986
Main classification: F28F9
IPC codes: B60H1, F28D1, F28F9