JP2019109038A - Heat recovery device and corresponding manufacturing process - Google Patents

Abstract

To provide a heat recovery device.SOLUTION: A wall part (41) of a grate (39) has a planar portion (65) that is oriented to a main body (19) around an orifice (43). The main body (19) has an opening (25) defined by a flat marginal part (69) which is pressed against the planar portion (65). The planar portion (65) and the flat marginal part (69) are firmly attached to each other so as to be made air-tight to exhaust gas.SELECTED DRAWING: Figure 5

Description

  The present invention relates generally to heat recovery devices for exhaust lines.

  A motor vehicle exhaust line may comprise a heat exchanger of the type shown in FIG. Such a heat exchanger 1 includes a plurality of exhaust gas circulation pipes 3. These tubes are held by the grate 5 at each of their longitudinal ends. The housing 7 is disposed around the tube 3 and the grate 5. The pipe 3, the grate 5 and the housing 7 are attached to each other by brazing in a furnace.

  Each grate 5 is provided with an upright edge 9 directed towards the outside of the heat exchanger so as to be mounted relative to the body 11, as shown in FIG. By integrating the body 11 into, for example, a three-way valve, exhaust gas can be selectively directed to the heat exchanger or to the heat exchanger bypass pipe. The end rim 13 of the upstanding edge 9 is between the grate 5 and the housing 7 so that the braze securing the grate 5 to the housing 7 does not melt during welding of the grate 5 onto the body 11 It must be sufficiently separated from the joint.

  The great 5 has a substantially rectangular shape. The grate 5 may be formed from a flat metal sheet, the sides of which are folded into a bowl shape, thus forming an upstanding edge 9. This metal sheet is then perforated to form an orifice for receiving the tube 3.

  During the forming of the flat metal sheet, the material is compressed at each corner of the upstanding edge 9. The surface condition inside the four corners is not good. Chews can be seen both inside and outside the bowl.

  Therefore, the forming of the grate makes it impossible to provide a good surface condition or a good dimensional margin at each corner of the upstanding edge 9.

  Furthermore, it becomes difficult to obtain good flatness of each of the sides of the upstanding edge 9. This is due to the elastic return of the material at the four corners.

  Furthermore, as can be seen in FIG. 2, the exchanger 1 can be mounted on a barrel stretcher 15 arranged in the body 11. The upstanding edge 9 is inserted into the interior of the barrel stretcher 15.

  Barrel extension is obtained by stretching rather than compression of the material, but the edge of the barrel stretcher 15 is never flat due to the elastic return of the material during molding. The edge of the barrel stretcher is not perpendicular to the plane of the opening defined in the body 11 and the undercut angle is about 2 °.

  Thus, the play between the upright edge 9 of the great and the barrel stretcher 15 is not constant and may average more than 0.5 mm.

  In the configuration shown in FIG. 2, it may be conceivable to butt weld the upstanding edge 9 and the barrel stretcher 15.

  In the exhaust field, the welding method conventionally used is MAG (Metal Active Gas (Metal Active Gas)). With such a welding method, large play between the upstanding edge and the barrel stretcher may cause defects or even holes.

  In the case of lap welding it is necessary to allow the upstanding edge 9 and the barrel stretcher 15 to pass over each other. However, the length of the upstanding edge 9 is limited by the fact that the compression of the material at the corners becomes impossible when the certain limit is exceeded.

  Similarly, the barrel stretcher has a maximum length in relation to the maximum allowable elongation of the material.

  Furthermore, the MAG method has several known disadvantages, the most significant of which is the deformation of the parts to be welded. Because these parts are heated to high temperatures and locally heated.

  This drawback is due to the fact that the axis of the flap can be rotated without interfering with the valve body, and for the valve body which must have a good final shape, in order for the valve to have a good sealing level. It is particularly fatal when the heat exchanger 1 has to be firmly mounted.

  In this context, the present invention aims to propose a heat recovery device which does not have the above drawbacks.

To this end, the invention is a heat recovery device for an exhaust line, which device comprises a body defining an exhaust gas circulation passage inside and a heat exchanger, the heat exchanger comprising
A housing having a proximal edge defining a proximal opening;
A plurality of exhaust gas circulation pipes extending inside the housing;
At least one grate disposed in the proximal opening, the wall portion having the orifices disposed therein, each tube engaging one of the orifices and being mounted on the grate The grate is extended around the wall and further has an upstanding edge projecting from the wall towards the interior of the heat exchanger, the upstanding edge being rigidly attached to the housing Equipped with at least one great,
-The wall of the grate has a flat surface directed towards the body around the orifice,
The body has an opening defined by a flat edge pressed against the plane,
-A heat recovery device, wherein the flat and flat edges are rigidly attached to one another in such a way that they are airtight against the exhaust gas.

  Thus, in the present invention, the greats are bent in the opposite direction as in FIG. This makes it possible to connect between the body and the grate in the plane of the grate surrounding the orifice receiving the tube. Thus, the barrel extension around the opening of the body is no longer necessary and the connection between the body and the grate is made in two planes parallel to one another.

  Advantageously, this makes it possible to secure the grate and the body either by a brazing method or a laser welding method.

  These methods are advantageous because they do not require significant heating of the parts, thus minimizing the risk of deformation of the body.

  Obtaining good flatness of the flat surface of the grate and the flat edge of the body is easier than monitoring the shape of the barrel extension or upstanding edge in the device of FIGS. 1 and 2.

  Furthermore, the height of the upstanding edge is much lower than the height in FIGS. 1 and 2. This is because there is no need to extend the height of the upstanding edge in FIGS. 1 and 2 to the free edge of the barrel stretcher. It is only necessary to provide a junction with the heat exchanger housing. The manufacture of the Great is easier and the deformation is less noticeable.

The heat recovery device may also have one or more of the following features in any combination considered individually or considered technically.
The flat and flat edges are rigidly attached to one another by laser welding or brazing.
The upright edge of the grate is rigidly attached to the proximal edge of the housing, the wall of the grate being offset towards the outside of the housing.
The plane has a closed contour and has a width of at least 2 millimeters.
The housing comprises a central tubular portion having a first linear cross section, the proximal opening having a second cross section larger than the first cross section.
The proximal edge of the housing is connected to the central tubular portion by a tubular segment extending from the central tubular portion, the tubular segment defining a heat transfer fluid circulation channel along the grate.
The housing has a heat transfer fluid inlet and a heat transfer fluid outlet, the heat transfer fluid inlet being arranged in the central tubular portion, the central tubular portion to move from the heat transfer fluid inlet to the heat transfer fluid circulation channel It has a zone extending towards the exterior of the housing extending along.
The tubes have ridges forming spacers which maintain a predetermined spacing between the tubes and between the tubes and the housing, all the ridges in contact with the housing transferring heat along the grate Located outside the fluid circulation channel.
The plane extends in the first plane, the orifice is surrounded by the ridges adjacent to the plane, the ridges being parallel to the first plane and thermally with respect to the first plane It extends in a second plane which is offset towards the interior of the exchanger.

According to a second aspect, the present invention is a method for manufacturing a device having the features described above,
Assembling the housing, the tube and the grate together by brazing;
Attaching the flat edges of the grate and the flat edges of the body to one another by laser welding or brazing.

  Other features and advantages of the present invention will become apparent from the detailed description of the present invention provided below, for reference and not limitation.

FIG. 2 is a cross-sectional view of a heat exchanger not according to the invention FIG. 2 is a cross-sectional view of one end of the heat exchanger of FIG. 1 mounted to a body. FIG. 5 is an exploded view of the heat exchanger of the heat recovery device according to the invention. FIG. 4 is a longitudinal cross-sectional view of the heat exchanger of FIG. 3 in an assembled state; 5 is a cross-sectional view of one end of the heat exchanger of FIGS. 3 and 4 mounted to the body. FIG. It is a perspective view of the heat exchanger of FIGS. 3-5. FIG. 7 is a bottom view of a heat exchanger for an alternative embodiment. 5 is an enlarged cross-sectional view of a portion of one of the heat exchangers of FIGS. 3 and 4; FIG. It is a perspective view of the great of FIG.

  The heat recovery device 17 is provided to be integrated into the exhaust line, typically the exhaust line of a vehicle equipped with a heat engine. The vehicle is, for example, a motor vehicle, typically a car or a truck.

  A heat recovery device 17 is provided to recover a portion of the thermal energy from the exhaust gases circulating in the exhaust line. The thermal energy thus recovered is used by being mounted on a vehicle, for example, to accelerate the temperature rise of the heat engine or to heat the cabin.

  The heat recovery device 17 shown in FIGS. 3 to 5 includes a main body 19 (FIG. 5) that defines the exhaust gas circulation passage 21 inside, and a heat exchanger 23.

  The main body 19 has an opening 25, and the circulation passage 21 communicates with the heat exchanger 23 through the opening 25.

  The main body 19 is, for example, a valve main body. In this case, the valve is typically a three-way valve, and the body 19 has at least one exhaust gas inlet and two outlets, all in fluid communication with the circulation passage 21. The inlet is in fluid communication with a collector that captures exhaust gases at the outlet of the combustion chamber of the heat engine. One of the outlets constitutes an opening 25 and communicates with the exhaust gas circulation side of the heat exchanger 23. The other outlet is connected to the heat exchanger bypass pipe. Only one opening 25 is shown in FIG.

  Alternatively, the main body 19 is an exhaust gas circulation pipe, and the heat exchanger is detour mounted on the pipe.

  As shown in FIGS. 3 to 5, the heat exchanger 23 includes a housing 27 and a plurality of exhaust gas circulation pipes 29 extending inside the housing 27.

  The tube 29 is in fluid communication with the circulation passage 21 via the opening 25.

  The housing 27 has a proximal edge 31 defining a proximal opening 33.

  The housing 27 also comprises a distal edge 35 defining a distal opening 37. The proximal edge 31 and the distal edge 35 have a closed contour.

  The heat exchanger 23 also comprises at least one grate 39 disposed in the proximal opening 33. The grate 39 comprises a wall 41 in which an orifice 43 is arranged.

  Each tube 29 has a proximal end 45 disposed in one of the orifices 43 and attached to a grate 39.

  Advantageously, the heat exchanger 23 comprises another grate 47 arranged in the distal opening 37. This further grate 47 comprises a wall 49 in which the orifice 51 is arranged. Each tube 29 has a distal end 53 engaged with one of the orifices 51 and attached to this other grate 47.

  Typically, the Great 39 and this other Great 47 are identical in all respects. Thus, only the Great 39 will be described in detail below.

  Preferably, the tube 29 is straight and extends longitudinally from the proximal end 45 to the distal end 53.

  For example, the tube 29 has a substantially rectangular cross-section that is constant along the entire longitudinal length of the tube 29 in a lateral plane that is perpendicular to the longitudinal direction. This cross section is long along the transverse direction T. The longitudinal direction L and the transverse direction T are shown in FIG.

  Thus, each tube 29 has two major faces 55, 57 located opposite one another and connected to one another by a shear edge 59. These major surfaces 55, 57 extend substantially in the plane including the longitudinal direction L and the transverse direction T. These planes are perpendicular to the upward direction E embodied in FIG.

  Advantageously, any tubes 29 are stacked along the ascending direction. In other words, the heat exchanger 23 comprises only a single tube in the lateral plane.

  Thus, each tube 29 extends substantially over the full width of the heat exchanger 23. The tubes 29 are stacked such that the large base 55 of a given tube is disposed opposite the large base 57 of the tube immediately below in a stack along the upward direction.

  Fins 61 are placed inside each tube 29 to promote heat exchange on the gas side. The fins 61 are produced, for example, in the form of a metal sheet which is bent into an accordion shape and inserted into the inside of the tube 29.

  The orifices 43 and 51 of the grate 39 and 47 have a shape that is paired with the orifice of the tube 29. Thus, these orifices 43 and 51 have a laterally elongated shape and extend over substantially the entire width of the grate. These orifices 43 and 51 are arranged in a single column.

  The grate 39 comprises an upstanding edge 60 extending around the wall 41 and projecting from the wall 41 towards the interior of the heat exchanger 23.

  In the example shown, the wall 41 is substantially rectangular with rounded corners. As a result, the upstanding edges 60 are substantially parallel to one another and with two segments 61 extending along the lateral direction T, substantially parallel to one another and along the ascending direction E And two extending segments 63. Preferably, the two segments 61 are parallel to one another and extend along the transverse direction T. Preferably, the two segments 63 are parallel to one another and extend along the ascending direction E. The segments 61 and 63 are connected to each other by a curved portion.

  The upstanding edge 60 projects along the longitudinal direction L. As shown in FIG. 4, the upstanding edge 60 engages within the proximal edge 31 of the housing 27, and the proximal edge 31 is pressed against the outer surface of the upstanding edge 60. The upright edge 60 is rigidly attached to the housing 27. More specifically, the proximal edge 31 is brazed onto the upstanding edge 60.

  The wall 39 of the grate 39 is offset towards the outside of the housing 27. The wall 41 is offset along the longitudinal direction L. That is, the wall portion 41 is not located inside the housing 27 and is located beyond the proximal end 31 of the housing 27 in the longitudinal direction.

  The wall 39 of the grate 39 has a flat surface 65 bent towards the body 19 around the orifice 43.

  Typically, the plane 65 extends in a predetermined plane. This plane is perpendicular to the longitudinal direction L and thus comprises a transverse direction T and an ascending direction E.

  The flat surface 65 extends around the entire circumference of the orifice 43. Thus, the plane 65 has a closed contour.

  The plane 65 has a width of at least 2 mm, for example between 2 mm and 5 mm. This width is measured along a direction perpendicular to the bond line 67 between the upstanding edge 60 and the wall 41. In other words, this width is measured along the ascending direction E along the segment 61 of the upstanding edge 60 and along the transverse direction T along the segment 63 of the upstanding edge 60.

  The flat surface 65 extends, in the example shown, to the joining line 67 between the upstanding edge 60 and the wall 41, ie to the outer edge of the wall 41.

  The opening 25 is cut out in the wall of the body 19.

  Typically, the openings 25 are cut out in a substantially planar zone 68 of the wall, which preferably has a flatness of less than 0.3. This planar zone 68 defines on one side the interior of the circulation passage 21 and is thus in direct contact with the exhaust gas. On the opposite side, this planar zone 68 is in contact with the heat exchanger 39.

  The opening 25 of the body 19 is defined by a flat edge 69 which is pressed against the plane 65.

  Thus, the flat edge 69 is in contact with the plane 65 on one side and in the opposite side of the plane 65 with the exhaust gas circulating in the body 19.

  The flat surface 65 and the flat edge 69 are rigidly attached to one another so as to be gas tight with respect to the exhaust gas.

  The flat surface 65 and the flat edge 69 are attached directly to one another.

  The flat surface 65 and the flat edge 69 are rigidly attached to one another by laser welding or brazing.

  The planar zone 68 has no relief around the flat edge 69 so as to be able to adjust the position of the grate 39 relative to the body 19.

  It should be noted that another grate 47 is also mounted above the flat zone to allow adjustment of the position of the heat exchanger ends relative to one another.

  The flat edge 69 has a flat outer surface 71 pressed against the flat surface 65 towards the heat exchanger 23.

  This planar outer surface 71 extends in a plane, which is perpendicular to the longitudinal direction L in the example shown.

  The edge 69 has a closed contour and extends all around the opening 25.

  The openings 25 are sized and shaped such that all orifices 43 are positioned in line with the openings 25. The proximal end 45 of the tube 29 projects beyond the grate 39 and penetrates somewhat inside the opening 25 as shown in FIG.

  The heat exchanger 23 also comprises a reinforcing grate 73 arranged to reinforce the connection between the tube 29 and the grate 39. The heat exchanger 23 advantageously comprises a further reinforcement grate 75 arranged to reinforce the connection between the tube 29 and the further grate 47. Great 73 and Great 75 are identical, and therefore only Great 73 will be described below.

  The reinforcing mass 73 is a plate in which the apertures 77 are arranged. Apertures 77 are defined by necks 79 (FIG. 5), each being penetrated by the proximal end 45 of one of the tubes 29. The apertures 77 are each disposed opposite one of the orifices 43. The neck 79 is brazed onto the tube 29. The outer edge 81 of the reinforcing plate and the field 83 located between the apertures 77 are brazed onto the inner surface of the wall 41.

  In the illustrated example, the proximal edge 31 and the distal edge 35 of the housing 27 are located at their two opposite longitudinal ends.

  The housing 27 is made of two half shells 85, 87. The half shells 85, 87 are fixed relative to one another by brazing along two longitudinal lines 89 (FIG. 6).

  Each half shell 85, 87 has a U-shaped cross section in a plane perpendicular to the longitudinal direction L.

  The housing 27 comprises a central tubular portion 91 having a first linear cross-section, and the proximal opening 33 has a second cross-section greater than this first cross-section (FIG. 4). Similarly, the distal opening 37 has a cross-section that is larger than the first cross-section and is typically equivalent to the second cross-section.

  For this purpose, the proximal edge 31 of the housing 27 is connected to the central tubular portion 91 by a tubular segment 93 extending from the central tubular portion 91.

  Similarly, the distal edge 35 of the housing 27 is connected to the central tubular portion 91 by another tubular segment 95 that flares from the central tubular portion 91.

  The tubular segment 93 defines a heat transfer fluid circulation channel 97 along the grate 39. Similarly, tubular segment 95 defines a heat transfer fluid circulation channel 98 in contact with another gore 47.

  The passage cross section provided to the heat transfer fluid by the circulation channel 97 and further by the channel 98 is substantially larger than the passage cross section in the heat exchanger shown in FIG.

  This occurs as a result of some structural arrangements of the heat exchanger.

  First, the plane 65 of the wall 41 is significantly wider in the present invention than in the heat exchanger of FIG. In fact, this plane 65 is intentionally made wide in the present invention to allow a good quality airtight fit of the flat edge 69 on the plane 65.

  Furthermore, as emphasized and mentioned above, in the present invention, the wall 41 is offset towards the outside of the housing 27. In the heat exchanger of FIG. 1, the wall in which the receiving orifice of the tube is arranged is arranged inside the housing 7.

  This large passage section 97 is particularly advantageous as it allows the heat transfer fluid flow in contact with the grate 39 to be increased. Typically, the gas 39 is located at the exhaust gas inlet inside the heat exchanger. However, the heat exchangers used in the exhaust line must never reach boiling point. This zone, where boiling is most critical, is always located on the exhaust gas inlet side, ie in the zone where the exhaust gas is at the highest temperature. When boiling, the heat transfer fluid turns into steam, and the heat exchange at the inlet of the heat exchanger is locally between the gases. As a result, the surface temperature of the exchanger can rise quickly and approach the temperature of the exhaust gas (e.g., about 850 ° C). This causes thermal shock and temperature gradients locally, resulting in failure and hence leakage in the braze that secures the various components of the heat exchanger together.

  Thus, in this type of heat exchanger, it is important that the heat transfer fluid flow rate in the grate 39 be sufficiently large to prevent boiling risk.

  The housing 27 has a heat transfer fluid inlet 99 and a heat transfer fluid outlet 101 (FIGS. 3 and 6).

  In the illustrated example, the heat transfer fluid inlet 99 and the outlet 101 are configured in a half shell 87. The heat transfer fluid inlets 99 and outlets 101 are arranged side by side and longitudinally offset with respect to each other. The inlet 99 is located on the side of the grate 39 and the outlet 101 is located on the side of the grate 47. In other words, the heat transfer fluid inlet 99 is located towards the exhaust gas inlet and the heat transfer fluid outlet 101 is located towards the exhaust gas outlet.

  The heat transfer fluid inlet 99 is located at the central tubular portion 91 of the housing 27. Advantageously, and as shown in FIG. 7, the central tubular portion 91 projects towards the outside of the housing 27 which extends along the grate 39 from the heat transfer fluid inlet 99 to the heat transfer fluid circulation channel 97 It has a zone 103.

  Zone 103 is not shown in FIGS.

  More specifically, the housing 27 has two major faces 105 and 107 substantially perpendicular to the rising direction E, and the faces 105 and 107 substantially perpendicular to the lateral direction T It has two side surfaces 109 to connect. The heat transfer fluid inlet 99 and typically the heat transfer fluid outlet 101 are disposed on one of the side faces 109. The projecting zone 103 is preferably arranged on the major surface 107. The protruding zone 103 has a substantially triangular shape as shown in FIG. The protruding zone 103 extends laterally from the heat transfer fluid inlet 99 to the opposite side 109 of the heat transfer fluid inlet 99. The width of the projecting zone 103 measured along the longitudinal direction decreases from the heat transfer fluid inlet 99 towards the opposite side 109 of the heat transfer fluid inlet 99.

  Advantageously, the projecting zone 103 projects relative to the central zone 111 of the central tubular portion 91 over a height substantially equal to the height of the proximal end 31.

  The protruding zone 103 enables the heat transfer fluid to be collected at the heat transfer fluid inlet 99 and to be preferentially directed to the circulation channel 97. This promotes cooling at the inlet of the heat exchanger and limits the boiling risk.

  Advantageously, the housing 27 also comprises another projecting zone 112 which extends along another grid 47 from the heat transfer fluid outlet 101 to the heat transfer fluid circulation channel 98 (FIG. 7).

  The projecting zone 112 is symmetrical to the projecting zone 103 with respect to the median plane of the heat exchanger which is perpendicular to the longitudinal direction L.

  The tubes 29 have ridges 113 forming spacers that maintain a predetermined spacing between the tubes 29 and between the tubes 29 and the housing 27. These ridges 113 are distributed over the major surfaces 55 and 57 of the tube.

  In the illustrated example, each major surface 55, 57 has about ten ridges 113.

  The raised portion 113 projects towards the outside of the tube 29. These raised portions 113 are obtained by deformation of the metal constituting the tube 29.

  The ridges 113 in contact with the housing 27 are all outside the heat transfer fluid circulation channel 97 along the grate 39, and typically also outside the heat transfer fluid circulation channel 98 along another grate 47. To position.

  This is advantageous for the mechanical strength between the housing 27 and the ridge 113.

  Preferably, these ridges are also located outside the projecting zone 103 and also outside the projecting zone 112.

  Typically, the raised portion 113 formed on the major surface 55 of the tube 29 is located opposite to the raised portion 113 formed on the major surface 57 of the tube 29. “Ahead” means that they are on opposite sides along the ascending direction E. Similarly, the ridge 113 formed on a given tube 29 is located in the extension of the ridge 113 of another tube 29 along the ascending direction E, as shown in FIG. In other words, all the tubes 29 have the same configuration on their two opposite sides 55, 57 so that the ridges 113 form a stack in the column along the ascending direction E. Having the raised portion 113. This is advantageous in increasing the rigidity of the heat exchanger 23.

  According to another advantageous aspect of the invention, the plane 65 of the grate 39 extends in the first plane P1, the orifice 43 is surrounded by the ridge 115 adjacent to the plane 65, the ridge 115 being It extends in a second plane P2 which is parallel to one plane P1 and which is offset towards the interior of the heat exchanger 23 with respect to the first plane P1. This is illustrated in FIG.

  The ridges 115 extend over the entire outer edge of the orifice 43. The ridge 115 has a closed contour and is adjacent to the inside of the plane 65. The ridges 115 are separated from the plane 65 by a step.

  Therefore, during brazing of the heat exchanger 23, it is impossible for the brazing material to spread on the flat surface 65. The brazing material is retained by the steps which separate the ridges 115 from the flat surface 65.

  According to another aspect, the present invention relates to a process for manufacturing the heat recovery device 17 described above.

The manufacturing process comprises the following steps:-assembling the housing 27, the tube 29 and the grate 39 together by brazing;
Mounting the flat surface 65 of the grate 39 and the flat edge 69 of the body 19 together by laser welding or brazing.

  Typically, in the assembling step, another grate 47 is assembled by brazing to the housing 27 and the tube 29.

  Furthermore, advantageously, the reinforcing grate 73, 75 is assembled by brazing to the tube 29 and the grate 39, 47 in the same step.

  Also, this assembly step makes it possible to fix the half shells 85, 87 of the housing 27 to each other.

  As described above, the housing 27 is assembled to the grate 39 by brazing the proximal edge 31 onto the upstanding edge 60.

  The tubes 29 are assembled to one another by brazing, which is preferably done at the ridges 113.

  The tube 29 is assembled to the housing 27 by brazing of the ridges 113 onto the housing 27 and more particularly onto the central tubular portion 91 of the housing 27.

  The brazing step is preferably carried out in a furnace.

  If the mounting of the plane 65 on the flat edge 69 is carried out by laser welding, this welding is done by the permeability through the flat edge 69. The welding line has a closed contour and extends over the entire outer edge of the opening 25.

  When the attachment is performed by brazing, brazing paste is placed between the flat edge 69 and the flat surface 65. The brazing paste is melted, for example, by disposing the main body 19 and the heat exchanger 23 in a furnace. In this case, brazing of the flat surface 65 and the flat edge 69 may be performed simultaneously with assembly by brazing the various elements of the heat exchanger together.

  The heat recovery device 17 and the corresponding manufacturing process can take several variants.

  The grate 47 disposed within the distal opening 37 of the housing 27 may be of a different type than the grate disposed within the proximal opening 33.

  The tube 29 does not necessarily have the shape described above. The tube 29 may have a circular cross section, an oval cross section, or any other suitable cross section. These tubes are not necessarily straight, but alternatively are curved. In this case, the distal opening 37 of the housing 27 is not necessarily disposed opposite to the proximal opening 33 in the longitudinal direction.

  The heat transfer fluid is typically a liquid. Alternatively, the heat transfer fluid is another type of fluid.

  The heat exchanger 23 is not necessarily symmetrical with respect to the central cross section of the heat exchanger. The heat exchanger 23 may not include the heat transfer fluid circulation channel 98 in contact with another bulk 47 and / or may not include the protruding zone 112.

  The wall 39 of the great 39 can have any type of shape. The wall 41 is not necessarily rectangular. Alternatively, this wall 41 is circular or oval or has any other suitable shape.

  In this case, the openings 25 arranged in the body 19 also do not have a rectangular shape. The opening 25 has a shape that typically corresponds to the shape of the grate 39, and more specifically to the shape of the wall 41.

  The upstanding edge 60 is not necessarily engaged to the inside of the proximal edge 31 of the housing 27 in order to attach the grate 39 to the housing 27. Alternatively, the upstanding edge 60 is the proximal edge 31 of the housing 27 engaged within the upstanding edge 60 of the grate 39.

  The housing 27 is not necessarily made of two half shells 85, 87 assembled together. The housing 27 may be obtained by winding a metal sheet around the longitudinal axis or by deforming the tube segment.

  The tube 29 can be arranged inside the heat exchanger 23 in various ways in any type. In particular, it is possible to arrange a plurality of tubes 29 adjacent to one another in the lateral direction, not just one as described above.

  The plane 65 does not necessarily extend in a single plane. The plane 65 may comprise a plurality of planar zones arranged in planes parallel to one another or inclined relative to one another. In these cases, flat edge 69 has substantially the same shape as plane 65. In either case, the flat edge 69 and the flat surface 65 contact each other over a zone having a closed contour surrounding the opening 25 and surrounding all the orifices 43, 51. This zone has a width sufficient to allow the flat surface 65 and the flat edge 69 to be attached to each other, preferably by laser welding or brazing.

Reference Signs List 1 heat exchanger, 3 exhaust gas circulation pipe, 5 grate, 7 casing, 9 upright edge, 11 body, 13 end rim, 15 barrel stretcher, 17 heat recovery device, 19 body, 21 exhaust gas circulation passage, 23 Heat exchanger, 25 opening, 27 housing, 29 exhaust gas circulation pipe, 31 proximal edge, proximal end, 33 proximal opening, 35 distal edge, 37 distal opening, 39 grate, 41 wall , 43 orifices, 45 proximal ends, 47 grates, 49 walls, 51 orifices, 53 distal ends, 55 large faces, large base, 57 large faces, large base, 59 sheared edges, 60 upstanding edges, 61 fins, segments, 63 segments, 65 planes, 67 joint lines, 68 planar zones, 69 flat edges, 71 planar outer surfaces, 73 reinforcements, 75 reinforcements Ht, 77 aperture, 79 neck, 81 outer edge, 83 fields, 85 half shells, 87 half shells, 91 central tubular portion, 93 tubular segments, 95 tubular segments, 97 heat transfer fluid circulation channels, large passage sections , 98 heat transfer fluid circulation channel, 99 heat transfer fluid inlet, 101 heat transfer fluid outlet, 103 protrusion zone, 105 face, 107 large surface, 109 side, 111 central zone, 112 protrusion zone, 113 ridge, 115 ridge, P1 1st surface, P2 2nd surface

Claims (11)

A heat recovery device for an exhaust line, said device (17) comprising: a main body (19) defining an exhaust gas circulation passage (21) inside; and a heat exchanger (23), the heat exchanger (23) is
A housing (27) having a proximal edge (31) defining a proximal opening (33);
A plurality of exhaust gas circulation pipes (29) extending inside the housing (27);
At least one grate (39) arranged in said proximal opening (33), said grate (39) comprising a wall (41) in which an orifice (43) is arranged, each A tube (29) engages the one of the orifices (43) and has a proximal end (45) attached to the grate (39), the grate (39) being the wall The upstanding edge (60) further comprising an upstanding edge (60) extending around the portion (41) and projecting towards the interior of the heat exchanger (23) from the wall (41) And at least one grate (39) rigidly attached to the housing (27);
The wall (41) of the grate (39) has a plane (65) directed towards the body (19) around the orifice (43);
Said body (19) has an opening (25) defined by a flat edge (69) pressed against said plane (65);
-A heat recovery device, wherein the flat (65) and the flat edge (69) are rigidly attached to one another so as to be airtight against exhaust gases.   The device according to claim 1, wherein the flat surface (65) and the flat edge (69) are rigidly attached to one another by laser welding or brazing.   The upstanding edge (60) of the grate (39) is rigidly attached to the proximal edge (31) of the housing (27) and the wall (41) of the grate (39) The device according to claim 1 or 2, wherein is offset towards the outside of the housing (27).   The device according to any of the preceding claims, wherein the plane (65) has a closed contour and has a width of at least 2 millimeters.   Claim 46. The housing (27) comprises a central tubular portion (91) having a first linear cross-section, the proximal opening (33) having a second cross-section greater than the first cross-section. A device according to any one of the preceding claims.   The proximal edge (31) of the housing (27) is connected to the central tubular portion (91) by a tubular segment (93) extending from the central tubular portion (91), the tubular segment (93) being The device according to claim 5, wherein a heat transfer fluid circulation channel (97) is defined along the grate (39).   The housing (27) has a heat transfer fluid inlet (99) and a heat transfer fluid outlet (101), the heat transfer fluid inlet (99) being disposed in the central tubular portion (91), The central tubular portion (91) has a zone (103) projecting towards the outside of the housing (27), the housing from the heat transfer fluid inlet (99) to the heat transfer fluid circulation channel ( A device according to claim 6, extending along the grate (39) up to 97).   The tubes (29) have ridges (113) forming spacers that maintain a predetermined spacing between the tubes (29) and between the tubes (29) and the housing (27). The heat transfer fluid circulation channel (97) according to claim 6 or 7, wherein the ridges (113) in contact with the housing (27) are all located along the grate (39). Device.   The plane (65) extends into the first plane (P1), the orifice (43) is surrounded by a ridge (115) adjacent to the plane (65), and the ridge (115) A second surface (P2) parallel to the first surface (P1) and offset towards the interior of the heat exchanger (23) with respect to the first surface (P1) 9. A device according to any one of the preceding claims, which extends inward.   A device according to any of the preceding claims, wherein the opening (25) is cut out in a wall of the body (19). 11. A method for manufacturing a device according to any one of the preceding claims,
Assembling the housing (27), the pipe (29) and the grate (39) together by brazing;
Mounting the flat edge (69) of the grate (39) and the flat edge (69) of the body (19) together by laser welding or brazing.