Heat Exchanger
20170248371 · 2017-08-31
Inventors
Cpc classification
F28D1/0233
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F28D1/05333
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F28F2275/122
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F28D7/1684
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F28F9/0219
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F28D21/0003
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
International classification
Abstract
The invention relates to a heat exchanger including exchange components and fluid flow components (2, 2′, 3), at least one fluid collecting tank (11, 11′) into which the exchange components open out (2, 2′, 3), at least one collecting plate (10) for holding the exchange components (2, 2′, 3) and a housing (4) for accommodating the exchange components (2, 2′, 3). The exchanger is characterized in that it includes a flange (5) for fixing the collecting tank (11, 11′) on the housing (4).
Thanks to the invention, the transmission of stresses from the flange (5) to the collecting plate (10) is avoided, which means that a thinner collecting plate (10) is able to be formed.
Claims
1-10. (canceled)
11. A heat exchanger including exchange components and fluid flow components, said heat exchanger comprising: a housing for accommodating the exchange components; a fluid collecting tank into which the exchange components open out; and a flange for fixing said fluid connecting tank to said housing, said flange including two peripheral grooves, a first one of said two peripheral grooves for holding said housing and a second one of said peripheral grooves for holding said fluid collecting tank.
12. The heat exchanger as claimed in claim 11, wherein each of said two peripheral grooves define an opening, with said opening of said first one of said two peripheral grooves opening in a direction opposite said opening of said second one of said two peripheral grooves.
13. The heat exchanger as claimed in claim 12, wherein said direction corresponds to a length L of the heat exchanger, said length L corresponding to the largest overall dimension of the heat exchanger and the overall direction of fluid flow in the heat exchanger.
14. The heat exchanger as claimed in claim 11, wherein said first one of said two peripheral grooves comprises: an internal longitudinal wall extending along its length in a direction corresponding to a length L of the heat exchanger, said length L corresponding to the largest overall dimension of the heat exchanger and the overall direction of fluid flow in the heat exchanger; an intermediate longitudinal wall extending along its length parallel to said internal longitudinal wall; and an internal transverse wall connecting said internal longitudinal wall to said intermediate longitudinal wall and extending in a direction between and transverse to said internal longitudinal wall and said intermediate longitudinal wall, wherein said internal longitudinal wall and said intermediate longitudinal wall define a first opening therebetween at a location remote from and opposite said internal transverse wall, said first opening in a direction corresponding to said length L of the heat exchanger.
15. The heat exchanger as claimed in claim 14, wherein said second one of said two peripheral grooves comprises: said intermediate longitudinal wall; an external longitudinal wall extending along its length in a direction parallel to said intermediate longitudinal wall; and an external transverse wall connecting said external longitudinal wall to said intermediate longitudinal wall and extending in a direction between and transverse to said external longitudinal wall and said intermediate longitudinal wall, wherein said external longitudinal wall and said intermediate longitudinal wall define a second opening therebetween at a location remote from and opposite said external transverse wall, wherein said second opening opens in a direction opposite said first opening.
16. The heat exchanger as claimed in claim 15, wherein said housing includes a wall extending in the direction corresponding to said length L of the heat exchanger, and wherein said wall is accommodated within said first one of said peripheral grooves such that an end of said wall is adjacent to said internal transverse wall, and wherein said fluid collecting tank includes a side edge extending in the direction corresponding to said length L of the heat exchanger, and wherein said side edge is accommodated within said second one of said peripheral grooves such that an end of said side edge is adjacent to said external transverse wall.
17. The heat exchanger as claimed in claim 16, wherein said wall is brazed to said flange within said first one of said peripheral grooves.
18. The heat exchanger as claimed in claim 15, wherein said flange further includes lugs extending from said external longitudinal wall opposite said external transverse wall for crimping said fluid collecting tank to said flange.
19. The heat exchanger as claimed in claim 18, wherein said lugs are hooked over said side edge of said fluid collecting tank to crimp said fluid collecting tank to said flange.
20. The heat exchanger as claimed in claim 11, wherein said flange is brazed to said housing and said housing includes at least one locating lug designed to be accommodated in an opening in said flange to hold this latter on said housing whilst both parts are being brazed.
21. The heat exchanger as claimed in claim 11 further comprising a collecting plate for holding the exchange components fixed to said housing.
22. The exchanger as claimed in claim 21, in which said flange and said collecting plate are fixed to said housing independently of each other and wherein said collecting plate is spaced from said flange.
23. The heat exchanger as claimed in claim 21, wherein the exchange components include tubes within which a first fluid is flow-connected to said fluid collecting tank and around which flows a second fluid, wherein said collecting plate provides a sealing between said first fluid and said second fluid and said flange provides a sealing between said first fluid and the outside of the heat exchanger.
24. The heat exchanger as claimed in claim 21, wherein said collecting plate is brazed to said housing.
25. The heat exchanger as claimed in claim 24, in which said collecting plate includes a skirt with an area along which said collecting plate is brazed to said housing.
26. The heat exchanger as claimed in claim 16, wherein said internal transverse wall includes an opening, and wherein an end of said wall includes a vane having a locating lug, said locating lug extending within said opening of said internal transverse wall.
27. The heat exchanger as claimed in claim 26, wherein said locating lug extends through said opening and is crimped to a surface of said internal transverse wall opposite said first one of said peripheral grooves.
28. The heat exchanger as claimed in claim 11, wherein the corners of said flange include a pushed-in portion at said first one of said peripheral grooves.
29. The heat exchanger as claimed in claim 28, further comprising a seal ring arranged at a bottom of said second one of said peripheral grooves adjacent to said external transverse wall.
30. The heat exchanger as claimed in claim 29, wherein the corners of said fluid collecting tank includes a swelling corresponding to each one of said pushed-in portions to hold said seal ring in position within said second one of said peripheral grooves.
Description
[0027] The invention will be better understood by way of the following description of the preferred embodiment of the exchanger of the invention, with reference to the sets of accompanying drawings, in which:
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[0043] With reference to the figures and more particularly to
[0044] The exchanger 1 describes a so-called “air-water” exchanger, that is to say an exchanger in which the fluids which exchange heat are air and water. It is, for example, a water cooler for so-called “recirculated” exhaust gases of a heat combustion engine for an automotive vehicle or perhaps a charge-air cooler for such an engine; the water is preferably so-called <<low temperature water from the cooling circuit of said engine; it is typically glycolized water.
[0045] With reference to
[0046] With reference to
[0047] Fins 2′ for agitating the air flow are mounted in the tubes 2 allowing the heat exchanges between the air and the water to be facilitated through the walls of the tubes 2. Said fins 2′ are well known to the person skilled in the art and it is not necessary to describe them in detail; in this case they have an undulating form and their cross section, when seen in an end view in the axis of the length L of the exchanger 1, is in the form of a coil between the walls of each tube 2.
[0048] The water flow agitators (not shown) are mounted in the water flow ducts 3 arranged between the tubes 2, said flow preferably being against the current, that is to say in the opposite direction to the direction of flow of the air. The agitators are in the form of plates which extend appreciably over the entire lateral area of the tubes 2 (the lateral area is the area of the tubes 2 defined by the dimensions parallel to the length L and to the width l of the exchanger 1) and in all the space between successive tubes 2 to which they are brazed; agitators are also provided between the end tubes 2 and the walls of the housing 4. The shape of the agitators creates the turbulence in the flow of water passing across them in order to promote the heat exchanges, in a known manner.
[0049] As alluded to further above, the exchanger 1 includes, at each of its ends (in the dimension of its length L), an air collecting tank 11, 11′. On the right-hand side (in
[0050] The structure of the exchanger will be described in more detail by its connection to the inlet tank 11. The description given applies equally to the exchanger at its output tank 11′. The input 11 and output tanks 11′, in this particular case, are similar and are mounted symmetrically; obviously, according to another embodiment, they can be different.
[0051] The exchanger 1 includes at its end a collecting plate 10, the function of which is to hold the tubes 2 in position, to guide the flow of air between the inside volume of the collecting tank 11 and the tubes 2 and to prevent water flowing toward the inside volume of the collecting tank 11, while preventing flows of air and water converging; in other words, the collecting plate 10 ensures the seal between the air and the water. The person skilled in the art often refers to the collecting plate 10 using the term collector 10 and it will be designated as such below.
[0052] The collector 10 is fixed to the housing 4, in this particular case by means of brazing, at an area of a peripheral edge. More precisely in this particular case, the collector 10 includes a peripheral skirt 10a having a lateral area along which the collector 10 is brazed to the housing 4; this allows for simpler positioning between said two parts before they are brazed but also for a better hold between the two since the contact area (and therefore the brazing area) is larger than if the collector 10 were brazed along an edge.
[0053] The peripheral skirt 10a is formed by the edge of the collector 10 which is bent over, in this particular case along its entire periphery. The skirt 10a therefore extends perpendicularly with respect to the overall plane of the plate forming the collector 10, in parallel, therefore, with the direction of the length L of the exchanger 1. The skirt 10a can be bent over in one direction (as in
[0054] With reference to
[0055] In the embodiment shown, the housing 4 includes two walls 15, 16 being formed into an L. In other words, each wall 15, 16 has a cross section (compared with the direction of the length L of the exchanger 1) in the shape of an L. Each wall 15, 16 is formed into an L by bending around an edge to form two vanes (15a, 15b), (16a, 16b) perpendicular with respect to each other. The idea of the walls 15, 16 in the shape of an L is their simplicity of manufacture and storage in view of the manufacture of the exchangers (storage being possible simply by assembling the walls together one on top of another).
[0056] More precisely, each wall 15, 16, in this case, includes a large vane 15a, 16a and a small vane 15b, 16b. The large vane 15a, 16a is in the form of a rectangular plate with dimensions appreciably equal to the length L of the exchanger 1 and to its width l, whilst the small vane 15b, 16b is in the form of a rectangular plate with dimensions appreciably equal to the length L of the exchanger 1 and to its height h. The concepts of large and small vanes are introduced here to allow each of the vanes (15a, 15b), (16a, 16b) of each wall 15, 16 to be designated in a distinct manner
[0057] The water inlet 9 and outlet pipes 8 into and out of the exchanger 1 are connected here to a same side of the exchanger 1, in this particular case to the small vane 16b of the second wall 16.
[0058] The walls 15, 16 of the housing 4 are fixed to each other around the exchange components 2, 2′, 3; in this particular case, they are brazed. To this end, each wall 15, 16 includes, at the free end of its small vane 15b, 16b, a raised edge 15c, 16c, which is an edge 15c, 16c to be fixed to the large vane 16a, 15a of the other wall 16, 15. Said raised edge 15c, 16c extends perpendicularly with respect to the small vane 15b, 16b, from an edge of the bend by means of which it is connected thereto. Crimping lugs R are arranged to ensure the connection between the raised edges 15c, 16c and the corresponding large vanes 16a, 15a. Brazing allows the contact areas to be locked together and held one against the other.
[0059] Once the walls 15, 16 have been fixed, the vanes (15a, 15b), (16a, 16b) of the walls 15, 16 formed into an L form the four lateral sides of the exchanger 1 (lateral sides are referred to with regard to the direction of its length L).
[0060] It is remembered here that in the embodiment described, the collector 10 is fixed to the housing 4 by means of brazing. More precisely, the outside area of its peripheral skirt 10a is brazed to the internal area of the vanes (15a, 15b), (16a, 16b) of the walls 15, 16.
[0061] One particular characteristic of the walls 15, 16 will be described now with reference to
[0062] It is noted that the walls 15, 16 each include two widenings E, respectively, in the direction of the height h of the exchanger 1, arranged close to each end of its large vane 15a, 16a. Said widenings E are formed here by chasing the wall 15, 16. They are provided as the dimensions of the collector 10 are greater, in the direction of the height h of the exchanger 1, than the dimension of the small vanes 15b, 16b of the walls 15, 16 in an L; these are therefore the widenings E (or stampings E) for accommodating the collector 10. Said stampings E have an additional advantage: insofar as they accommodate the collectors 10 in the direction of the height h of the exchanger 1, they form a stop in the dimension of the length L of the exchanger 1; thus, they form axial holding means (in this direction L) for the collectors 10 and therefore for all the exchange components 2, 2′ whilst all the components of the exchanger 1 are being brazed.
[0063] Furthermore, the exchanger 1 includes a flange 5 for fixing the collecting tank 11 to the housing 4. Said flange 5 is brought onto the housing 4. It is fixed (in this particular case by means of brazing) to the end of the housing 4, along the periphery of said housing; this is therefore a peripheral flange 5, with an overall rectangular form, in this particular case formed from one single part. It is fixed to the housing 4 independently of the collector 10 and is not fixed to this latter; in other words, the exchanger 1 does not include any means for fixing the flange 5 to the collector 10.
[0064] The flange 5 includes an internal longitudinal wall 17 (in the direction of the length L) which extends along its entire periphery; said internal longitudinal wall 17 is arranged in order to extend from the internal side of the walls 15a, 15b, 16a, 16b of the housing 4 and to be brazed to them.
[0065] The internal longitudinal wall 17 is bent out toward the outside and in the direction of the exchanger 1, thus forming an internal transverse wall 18 and an intermediate longitudinal wall 19 providing, with the internal longitudinal wall 17, a peripheral groove G1 for accommodating the walls 15a, 15b, 16a, 16b of the housing 4, fulfilling a function of fixing the housing 4 in this way. The internal transverse wall 18 forms a stop for the end of the walls 15a, 15b, 16a, 16b of the housing 4.
[0066] The intermediate longitudinal wall 19 is bent out toward the outside and in the opposite direction of the bend forming the peripheral groove G1, thus forming an external transverse wall 20 and an external longitudinal wall 21 providing, with the intermediate longitudinal wall 19, a peripheral groove G2 for accommodating a side edge 11a of the end of the collecting tank 11, fulfilling a function of fixing the collecting tank 11 in this way; this is the end of the tank 11 by means of which it is fixed to the flange 5; the side edge 11a of the tank 11 will be called the fixing edge 11a.
[0067] Thus, the flange includes two peripheral grooves G1, G2 formed by the walls 17, 18, 19, 20, 21 of the flange 5, said grooves G1, G2 including a common wall 19. Each groove G1, G2 is provided for holding a part, in this particular case for holding the housing 4 and the collecting tank 11, respectively. More precisely, the housing 4 and the collecting tank 11 are each arranged so that their longitudinal end walls (in the direction of the length L of the exchanger 1) are inserted longitudinally into a peripheral groove G1, G2, by means of the transverse opening in said groove G1, G2. The grooves G1, G2 are oriented in opposite directions, that is to say that their openings are turned in two opposite directions in the direction of the length L of the exchanger 1. On account of their structure with a common wall 19, they provide the exchanger 1 with great compactness and a high level of hold for the parts 4, 11, whether this be in view of their brazing (for the housing 4) or in view of their crimping (for the collecting tank 11). Indeed, the collecting tank 11 and the housing 4 are fixed to each other in a compact manner without actually being fixed directly to each other, which ensures that the assembly is sturdy and notably allows for good stress transmission.
[0068] In the extension of the external longitudinal wall 21, the flange 5 includes lugs 22 for crimping the tank 11 to the flange 5. Said lugs 22 are arranged so as to be hooked (bent over) on the fixing edge 11a. The crimping lugs 22 are shown bent over (that is to say in the crimping position) in all the figures. The tank 11 is therefore crimped to the flange 5.
[0069] With reference in particular to
[0070] The holding of the tubes 2 is ensured by the collector 10 and the holding of the collecting tank 11 is ensured (by crimping) by the flange 5, itself brazed to the housing 4, the collector 10 and the flange 5 both being brazed to the housing 4 but, in this case, independently of one another; in this particular case, they do not even contact one another. In this way, the stresses to which the flange 5 is subjected on account of its function of holding the collecting tank 11 are not transmitted directly to the collector 11 which is connected to the housing 4 and to the tubes 2.
[0071] Insofar as the stresses applied to the flange 5 are not transmitted to the collector 11, this latter can be formed so as to be able to receive the tubes 2 with a streamlined cross section and separated from each other by a small spacing. In particular, it is possible to form the collector 11 by means of a traditional chasing process on plate with a very thin thickness; in such a process, the collars 13 of the collector 11 are stamped then their bottom is punched in order to form the openings, in a known manner. By way of example, as the plate allowing the collector 10 to be formed has a thickness of approximately 1 mm, a collector 10 can be formed with openings 12 of 100 mm by 7 or 8 mm approximately, with an inter-tube space of 2 to 3 mm. The space occupied (dimension parallel to the direction of the length L of the exchanger 1) by the collars 13 can be appreciably equal to 4 mm; in this way, by removing the thickness of the straps 14 (1 mm), the collars 13 have a useful area for the application of the end of the tubes 2 and for brazing thereto of approximately 3 mm.
[0072] Furthermore, as the collector 10 is brazed directly to the housing 4, the radius of its corners is relatively large and the collector 10 is simpler to manufacture, which is of interest as, on account of the thickness of the collector 10, it is not always easy to form it correctly.
[0073] One additional advantage is that, industrially, the invention can be implemented with collectors of the prior art, which are thin but not very strong, simply by adding a flange 5.
[0074] The openings 23 for receiving the locating lugs 24 protruding longitudinally out of the vanes 15a, 15b, 16a, 16b of the housing 4 are arranged in the internal transverse wall 18 of the flange 5 (that is to say in the bottom of the groove G1). Each lug 24 extends in the extension of the vane 15a, 15b, 16a, 16b supporting it; one vane 15a, 15b, 16a, 16b can include one or several lugs 24; all the vanes 15a, 15b, 16a, 16b or just some of them can include one or several lugs 24. In this particular case, the exchanger 1 includes one locating lug 24 located in the middle of the end of each small vane 15a, 16a of the housing 4 and two locating lugs 24 located at the end of each large vane 15b, 16b of the housing 4.
[0075] The locating lugs 24 are arranged so as to be able to be bent over or deformed so as to hold the flange 5 in position in relation to the housing 4 by means of crimping. The function of their deformation is also to ensure they are brazed perfectly to the inside areas of the openings 23 into which they are inserted so as to take up the mounting clearance with said areas and to avoid any air escaping here, in other words to ensure the sealing of the openings 23. To this end, the lugs 24 can be bent over against the internal transverse wall 18, for example by resting on this latter itself abutting against the end edge of the vanes 15a, 15b, 16a, 16b of the housing 4. They can also simply be deformed rather than crimped, inasmuch as simple deformation would preclude any movement in relation to the flange 5.
[0076] The function of said lugs 24 is to allow the positioning and the holding of the flange 5 on the housing 4 during the manufacture of the exchanger 1 and in particular before and during the brazing of its various constituent components.
[0077] The manufacture of the exchanger 1 is made easier in this way. The tubes 2 are stacked and inserted into the openings of the collectors 10 and the L-shaped walls 15, 16 of the housing 4 placed around them and held in position one with respect to another thanks to the crimping lugs R; it can be noted here that other holding means such as clinching means could be provided. The flanges 5 are moved to the ends of the housing 4, the locating lugs 24 being inserted into the openings 23 provided for this purpose and deformed, bent over or crimped to ensure the holding of the assembly. Everything can then be brazed and is placed in a furnace for this purpose, in a known manner. The areas intended to be brazed to the housing 4 (and notably the outside areas of the skirts 10a of the collectors 10 and the areas of the grooves G1) have consistent dimensions, which allows for quality brazing, the contact areas being large. The input 11 and output collecting tanks 11′ can then be crimped to the exchanger 1, in this particular case whilst arranging a seal ring 27 in the bottom of the groove G2 receiving the fixing edge 11a of the tank 11, in a known manner; this is an O-ring 27 which is shown schematically in
[0078] One particular characteristic of the exchanger 1 can be seen in
[0079] Such a pushed-in portion 25 is provided for facilitating the manufacture of the flange 5 and for promoting the quality of its brazing on the housing 4, by ensuring a sufficient brazing area including in the corners. Indeed, the flange 5, in this particular case, is formed by chasing and it is difficult to bend the material in the corners, as is known. Thus, thanks to the pushed-in portions 25, the quantity of material in the corners is less great, which allows them to be chased in such a way so as to form an internal longitudinal wall which has, including in the corners, sufficient length to enable quality brazing to the housing 4.
[0080] Obviously, the shape of the housing, and more particularly the shape of the corners of the ends of the housing 4, is adapted to the shape of the flange 5, as can be seen, for example, in
[0081] The collecting tank 11 includes, at each corner, a swelling 26 corresponding to the pushed-in portion 25 of the flange 5. Said swelling 26 is accommodated in the pushed-in portion 25, ensuring a function of holding the seal ring 27 in position; indeed, the seal ring 27 would not be contained in the corners on account of the pushed-in portions 25 of the flange 5.
[0082] The second, third, fourth and fifth embodiments of the flange 5 of the exchanger 1 can be seen in
[0083] In the second embodiment shown in
[0084] In the third embodiment shown in
[0085] In the fourth embodiment shown in
[0086] In the fifth embodiment shown in
[0087] The operation of the exchanger 1 (whatever its embodiment) is as follows (it is described in a concise manner as it is well known by the person skilled in the art). Air is supplied to the air input tank 11, flows in the tubes 2 (said flow being agitated by the fins 2′) and leaves the exchanger 1 again by means of the air outlet tank 11′. Furthermore, water is supplied to the exchanger through the water inlet pipe 9, circulates in the water flow ducts 3 (said circulating being agitated by means of the agitators) and leaves the exchanger 1 again by means of the water outlet pipe 8. The flows of air and water are counter-directional in the direction of the length L of the exchanger 1; this is called a “countercurrent” heat exchanger; the efficiency of such an exchanger 1 is very good.
[0088] The heat exchanger 1 has been described in connection with air circulating in its tubes 2 and water circulating between the tubes by means of the agitators. It goes without saying that this could be reversed, that is to say water in the tubes and air between the tubes. Furthermore, it could also be air in both cases or water in both cases, or other fluids.
[0089] The invention has been described in connection with preferred embodiments, but it goes without saying that other embodiments are conceivable. In particular, the characteristics of the different embodiment described can be combined together, if there are no incompatibilities.