DE102017203163A1 - Heat exchanger for a motor vehicle - Google Patents

Abstract

The invention relates to a heat exchanger (1) for a motor vehicle, the heat exchanger (1) having a heat exchanger stack (2) with at least one hot fluid duct arrangement (3), with at least one cold fluid duct arrangement (4) and with at least one thermoelectric element (5). Through the hot fluid channel arrangement (3) a hot fluid (6) can flow in a hot fluid direction (7) and through the cold fluid channel arrangement (4) a cold fluid (8) flows in a cold fluid direction (9). The heat exchanger (1) has a bracing arrangement (12) with a first clamping plate (13a) and with a second clamping plate (13b), wherein the first clamping plate (13a) and the second clamping plate (13b) the heat exchanger stack (2) in a stacking direction (15) tense. According to the invention, the tensioning arrangement (12) comprises a first frame plate (16a) and a second frame plate (16b), wherein the first frame plate (16a) and the second frame plate (16b) the heat exchanger stack (2) with a hot fluid outlet (10a) and with a Hot fluid inlet (10b) clamp in the hot fluid direction (7).

Description

The invention relates to a heat exchanger for a motor vehicle.

In a heat exchanger, the heat from a hotter fluid - for example, exhaust gases - to a colder fluid - for example, to a coolant - transferred. In the heat exchanger a plurality of fluid tubes having a plurality of channels for the colder fluid and for the hotter fluid are arranged alternately to a heat exchanger stack. The hotter fluid and the colder fluid are each distributed by a feed collector and a drain collector in the individual fluid pipes or collected by the individual fluid pipes.

Between the adjacent fluid pipes for the colder fluid and for the hotter fluid thermoelectric elements can be arranged, which allow a recovery of energy. The heat exchanger stack can - as in the publications DE 10 2007 063 173 A1 . JP 2007 221 895 A and US 5,584,183 described - are braced by bracing in a stacking direction.

Thermal expansion of the fluid tubes and the thermoelectric elements in the stacking direction, however, leads to distortion of the fluid tubes at contact points with the inlet collector and with the drain collector in the heat exchangers known from the prior art. This distortion can damage the heat exchanger.

The object of the invention is therefore to provide a heat exchanger in which the above-mentioned disadvantages are overcome and a risk of damage to contact points is reduced.

This object is achieved by the subject of independent claim 1. Advantageous embodiments are the subject of the dependent claims.

The present invention is based on the general idea to provide a heat exchanger in which a risk of damage is reduced. For this purpose, the heat exchanger has a heat exchanger stack with at least one hot fluid channel arrangement, at least one cold fluid channel arrangement and with at least one thermoelectric element, the thermoelectric element being arranged between the respective hot fluid channel arrangement and the respective cold fluid channel arrangement. By virtue of the hot fluid channel arrangement, a hot fluid can flow in a hot fluid direction, and through the cold fluid channel arrangement, a cold fluid can flow at least regionally in one of the hot fluid direction substantially orthogonal cold fluid direction. The heat exchanger also has a tensioning arrangement with a first tensioning plate and a second tensioning plate, wherein the first tensioning plate and the second tensioning plate are arranged on opposite stacking surfaces of the heat exchanger stack and clamp the heat exchanger stack in one of the hot fluid direction and the cold fluid direction substantially orthogonal stacking direction. According to the invention, the tensioning arrangement comprises a first frame plate and a second frame plate, wherein the first frame plate and the second frame plate are arranged on opposite frame surfaces / frame ends of the heat exchanger stack. The first frame plate and the second frame plate clamp the heat exchanger stack with a hot fluid inlet and a hot fluid exit in the hot fluid direction.

The heat exchanger stack is clamped in the stacking direction between the first clamping plate and the second clamping plate, so that a better surface contact of the hot fluid channel arrangement and the cold fluid channel arrangement is achieved with the respective thermoelectric element. Thereby, the heat transfer can be increased and consequently a higher efficiency of the thermoelectric element can be achieved. Advantageously, materials with different thermal expansion coefficients, such as, for example, metals, metal alloys, ceramics, plastics or other materials, can thereby also be used in the heat exchanger.

In addition, the respective hot fluid channel assemblies, the respective cold fluid channel assemblies, and the respective thermoelectric elements are frictionally locked together between the clamping plates so that the hot fluid channel assemblies, the cold fluid channel assemblies, and the thermoelectric elements remain independently expandable in the cold fluid direction or in the hot fluid direction and thereby mechanical constraints in the heat exchanger stack be minimized. Further heat conducting layers for improving the heat transfer can be defined in a reduced-cost manner between the thermoelectric element and the cold fluid channel arrangement as well as the hot fluid channel arrangement. By the heat conducting layers, the efficiency of the thermoelectric element can be further improved. According to the invention, the heat transfer stack is clamped in the hot fluid direction by the first frame plate and by the second frame plate and the hot fluid outlet and the hot fluid inlet are frictionally fixed to the respective hot fluid channel arrangement. In a thermal expansion of the heat exchanger stack in the stacking direction is characterized a distortion of the Hot fluid duct assemblies advantageously reduced at contact points with the hot fluid outlet and with the hot fluid inlet, so that the risk of damage is minimized. Advantageously, mechanical disturbances - such as vibration or vibration - transmitted attenuated to the heat exchanger stack, so that the risk of damage can be further reduced.

Furthermore, by the strain of the heat exchanger stack in the hot fluid direction higher thermal expansions of the heat exchanger stack can be compensated in the stacking direction, so that the heat exchanger according to the invention compared to a conventional heat exchanger can have more Heißfluidkanalanordnungen more Kaltfluidkanalanordnungen and correspondingly more thermoelectric elements. Overall, this can increase the recovery of energy. In addition, the manufacturing effort and the production costs can be reduced by the frictional connection of the Heißfluidkanalanordnungen.

Since the individual Heißfluidkanalanordnungen, the individual cold fluid channel arrangements and the individual thermoelectric elements in the stacking direction positively to each other and in the hot fluid direction frictionally fixed to the hot fluid outlet and the hot fluid inlet, they can be replaced in case of damage in a cost-reduced manner. As a result, both the repair costs and the repair costs can be significantly reduced.

In order to reduce unwanted deformation of the first frame plate and the second frame plate under tension and to meet requirements for sealing surfaces between the hot fluid exit and the hot fluid inlet and the hot fluid channel assemblies, the geometry and material of the first frame plate and the second frame plate may be adjusted accordingly.

In an advantageous development of the heat exchanger according to the invention, it is provided that the hot fluid outlet on the first frame plate and the hot fluid inlet on the second frame plate are integrally formed. Thus, the first frame plate and the second frame plate each have a bracing edge and an approximately centrally disposed Ausformbereich, which can be braced by the bracing edge of the heat transfer stack and can be integrally formed on the Ausformbereich the hot fluid outlet or the Heißfluideintritt. By such a design of the frame plates fewer components in the heat exchanger necessary, so that the manufacturing cost can be advantageously reduced.

The geometry and material of the first frame plate and the second frame plate may be adjusted to reduce undesirable deformation of the first frame plate and the second frame plate under tension and to meet sealing surface requirements between the hot fluid exit and the hot fluid inlet and the hot fluid channel arrangements.

In order to fix the first frame plate and the second frame plate to each other and to clamp the heat exchanger stack, it is advantageously provided that the first frame plate and the second frame plate are connected to the heat exchanger stack arranged therebetween by at least one clamping element. The clamping elements can connect the first frame plate and the second frame plate, for example, at the bracing edges on opposite frame sides, so that the heat exchanger stack is uniformly braced and the hot fluid outlet and the hot fluid inlet with the hot fluid channel arrangements are frictionally fixed to one another. The tensioning element can be for example a threaded rod or a clamp or a tension belt.

Advantageously, it is provided in a further development of the heat exchanger according to the invention that the first clamping plate and the second clamping plate on the first frame plate and on the second frame plate frictionally or positively - are fixed - for example by connecting bolts - and thereby form a Rahmengurt to the heat exchanger stack. In this way, the bracing arrangement can be stiffened so that undesired deformation in the heat exchanger stack is advantageously prevented.

In order to compensate for distortion of the Heißfluidkanalanordnungen, the Kaltfluidkanalanordnungen and the thermoelectric elements even at a higher thermal expansion in the stacking direction, it is advantageously provided that the bracing assembly has at least one sealing plate which is disposed between one of the frame surfaces of the heat exchanger stack and the respective frame plate of the tensioning arrangement , The seal plate forms a plain bearing for the hot fluid channel assemblies, for the cold fluid channel assemblies as well as for the thermoelectric elements on the frame plate, and mechanical stresses can be reduced.

It is advantageously provided that a cold fluid outlet with at least one of the cold fluid channel arrangements are fluid-conductively connected by a sealing element and / or a cold fluid inlet to at least one of the cold fluid channel arrangements by a sealing element. The sealing elements can thereby be sealing and flexible, so that mechanical stresses between the cold fluid channel arrangement and the cold fluid outlet and the cold fluid inlet can be reduced and a sealing connection between the cold fluid channel arrangements and the cold fluid outlet and the cold fluid inlet is achieved. Advantageously, it is provided that the bracing arrangement has at least one pressure plate, which rests against one of the stacking surfaces of the heat exchanger stack and which is fixed to the respective clamping plate by at least one spring element spaced. If the bracing arrangement has a pressure plate, the thermal expansion of the heat exchanger in the stacking direction is compensated on one side. In order to halve the thermal expansion to be compensated by the spring element or by the spring elements, the bracing arrangement can each have on both sides a pressure plate with at least one spring element. The spring element may be, for example, a plate spring, a leaf spring or a compression spring. Other potential energy stores can also be used.

In order to prevent heating of the pressure plate and to minimize the heat transfer in the clamping plates and in the frame plates, it is advantageously provided that a cold fluid channel arrangement is arranged at least on one of the stacking surfaces of the heat exchanger stack and that the pressure plate is arranged adjacent to the cold fluid channel arrangement. Thus, on both sides of the stack surfaces of the heat exchanger stack, the cold fluid channel arrangements are arranged, which are traversed by the cold fluid. The cold fluid channel arrangements have the lowest temperature in the heat exchanger stack and the heat transfer into the adjacent pressure plates and further into the spring elements, in the clamping plates and in the frame plates remains low. Thus, not only the spring elements are spared, but also the thermal load on the heat exchanger is reduced overall.

For the storage of the spring elements and the pressure plate on the tensioning arrangement is provided that the spring element and the pressure plate are slidably fixed to the respective clamping plate by a guide pin and a threaded sleeve in the stacking direction. The guide pin can be arranged displaceably in the threaded sleeve in the stacking direction and be fixed to the pressure plate, for example by a screw connection. The threaded sleeve can then be fixed to the clamping plate, so that the pressure plate is slidably fixed to the clamping plate by the sliding in the threaded sleeve guide pin in the stacking direction. A tension of the pressure plate is achieved by the spring element, which is arranged for example around the guide pin between the pressure plate and the clamping plate. The displacement of the guide pin in the stacking direction is limited on one side by the pressure plate. On the other hand, the displacement of the guide pin in the stacking direction can be limited, for example, by a stop element. In this way, the heat exchanger stack between the pressure plates or alternatively between the pressure plate and the opposite clamping plate can be braced and the thermal expansion of the heat exchanger stack in the stacking direction can be compensated advantageous.

Other important features and advantages of the invention will become apparent from the dependent claims, from the drawings and from the associated figure description with reference to the drawings.

It is understood that the features mentioned above and those yet to be explained below can be used not only in the particular combination given, but also in other combinations or in isolation, without departing from the scope of the present invention.

Preferred embodiments of the invention are illustrated in the drawings and will be described in more detail in the following description, wherein like reference numerals refer to the same or similar or functionally identical components.

• 1 eine Ansicht eines erfindungsgemäßen Wärmeübertragers;
• 2 eine Seitenansicht des in 1 gezeigten Wärmeübertragers mit einem angezeigten Heißfluidfluss;
• 3 eine weitere Seitenansicht des in 1 gezeigten Wärmeübertragers mit einem angezeigten Kaltfluidfluss;
• 4 eine Schnittansicht eines verspannten Wärmeübertragerstapels des in 1 gezeigten Wärmeübertragers;
• 5 eine Schnittansicht einer Spannplatte des in 1 gezeigten Wärmeübertragers.

It show, each schematically

• 1 a view of a heat exchanger according to the invention;
• 2 a side view of the in 1 shown heat exchanger with an indicated hot fluid flow;
• 3 another side view of the in 1 shown heat exchanger with a displayed flow of cold fluid;
• 4 a sectional view of a strained heat exchanger stack of in 1 shown heat exchanger;
• 5 a sectional view of a clamping plate of in 1 shown heat exchanger.

In 1 is a view of a heat exchanger according to the invention 1 and in 2 and in 3 are side views of the in 1 shown heat exchanger 1 shown. The heat exchanger 1 has a heat exchanger stack 2 with hot fluid channel arrangements 3 , with cold fluid channel arrangements 4 and with thermoelectric elements 5 on. The thermoelectric elements 5 are between the hot fluid channel arrangements 3 and the cold fluid channel assemblies 4 arranged, so that by a temperature gradient, a recovery of electrical energy is possible. Through the hot fluid channel arrangements 3 a hot fluid flows 6 in a hot fluid direction 7 and by the cold fluid channel arrangements 4 a cold fluid flows 8th at least in some areas in one of the hot fluid direction 7 essentially orthogonal cold fluid direction 9 , The hot fluid 6 is due to a hot fluid outlet 10a and a hot fluid inlet 10b - constructed here as diffusers - and the cold fluid 8th is due to a cold fluid outlet 11a and a cold fluid inlet 11b collected and distributed.

The heat exchanger 1 also has a tension arrangement 12 with a first clamping plate 13a and with a second clamping plate 13b on, with the first clamping plate 13a and the second clamping plate 13b on opposite stacking surfaces 14a and 14b of the heat exchanger stack 2 are arranged. The clamping plates 13a and 13b clamp the heat exchanger stack 2 in one of the hot fluid directions 7 and the cold fluid direction 9 essentially orthogonal stacking direction 15 , Due to the tension of the heat exchanger stack 2 will make better surface contact of the hot fluid channel assemblies 3 and the cold fluid channel arrangements 4 with the thermoelectric elements 5 and consequently achieves a higher efficiency. Since the Heißfluidkanalanordnungen 3 , the cold fluid channel arrangements 4 and the thermoelectric elements 5 are fixed to each other non-positively, they can independently in the hot fluid direction 7 and in the cold fluid direction 9 expand. As a result, mechanical constraints in the heat exchanger stack 2 advantageously minimized.

According to the invention, the tensioning arrangement 12 a first frame plate 16a and a second frame plate 16b on, with the first frame plate 16a and the second frame plate 16b on opposite frame surfaces 17a and 17b of the heat exchanger stack 2 are arranged. The hot fluid outlet 10a is on the first frame plate 16a and the hot fluid inlet 10b is on the second frame plate 16b integrally formed. The frame plates 16a and 16b clamp the heat exchanger stack 2 with the hot fluid outlet 10a and with the hot fluid inlet 10b in the hot fluid direction 7 , The hot fluid outlet 10a and the hot fluid inlet 10b are frictionally connected to the hot fluid duct assemblies 3 set, so that at a thermal expansion of the heat exchanger stack 2 in the stacking direction 15 thereby distorting the hot fluid channel assemblies 3 at contact points with the hot fluid exit 10a and advantageously reduced with the hot fluid inlet 10b. Between the cold fluid channel arrangements 4 and the cold fluid exit 11a and the cold fluid inlet 11b For this purpose sealing elements 11 are arranged. The sealing elements 11 connect the cold runner outlet 11a and the cold runner entry 11b sealed to the outside and fluid-conducting and flexible with the cold fluid channel arrangements 4 , allowing mechanical stresses in the hot fluid direction 7 can also be reduced advantageously here.

4 shows a sectional view of the strained heat exchanger stack 2 of the heat exchanger 1 , The frame plates 16a and 16b are on the opposite frame surfaces 17a and 17b of the heat exchanger stack 2 arranged and by clamping elements 18 braced. The clamping elements 18 are made here in the form of threaded rods and clamp the heat exchanger stack 2 in the hot fluid direction 7 , The clamping plates 13a and 13b are on the frame plates 16a and 16b non-positively by connecting bolts 19a and 19b and form a frame belt 19 around the heat exchanger stack 2, wherein the frame belt 19 an undesirable deformation in the heat exchanger stack 2 can prevent. Between the frame surfaces 17a and 17b of the heat exchanger stack 2 and the frame plates 16a and 16b are sealing plates 20a and 20b arranged, which is a sliding bearing for the Heißfluidkanalanordnungen 3 , for the cold fluid channel arrangements 4 as well as for the thermoelectric elements 5 on the frame plates 16a and 16b form and reduce mechanical stresses.

5 shows a sectional view of the tensioning arrangement 12 on the clamping plate 13a , The tensioning arrangement 12 has a pressure plate 21 on that at the stacking area 14a of the heat exchanger stack 2 abuts and the to the clamping plate 13a by spring elements 22 is set apart. The spring element 22 is a plate spring in this embodiment, but may also be a leaf spring or a compression spring. The heat exchanger stack 2 points to the stacking surface 14a the cold fluid channel arrangement 4 on, leaving the pressure plate 21 at the cold fluid channel arrangement 4 is applied and heating the pressure plate 21 is advantageously prevented. The printing plate 21 and the spring elements 22 are on the clamping plate 13a through guide bolts 23 and threaded sleeves 24 established. The guide pins 23 are in the threaded sleeves 24 in the stacking direction 15 slidably arranged and are on the pressure plate 21 by screws 25 established. The threaded sleeves 24 are fixed to the clamping plate 13a and the pressure plate 21 can relative to the clamping plate 13a in the stacking direction 15 be moved. The spring elements 22 are around the guide pins 23 arranged and allow over the frame belt 19 a strain of the heat exchanger stack 2 , Through the pressure plate 21 and stop elements 26 is the displacement of the guide pins 23 in the stacking direction 15 limited on both sides.

Due to the tension of the heat exchanger stack 2 in the stacking direction 15 and in the hot fluid direction 7 can be a thermal expansion of the heat exchanger stack 2 in the stacking direction 15 be compensated advantageous, so that the risk of damage is minimized. Advantageously, also the efficiency of the heat exchanger 1 be increased and the repair costs and production costs are reduced.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102007063173 A1 [0003]
• JP 2007221895 A [0003]
• US 5584183 [0003]

Claims (11)

Heat exchanger (1) for a motor vehicle, - wherein the heat exchanger (1) has a heat exchanger stack (2) with at least one hot fluid channel arrangement (3), at least one cold fluid channel arrangement (4) and at least one between the respective hot fluid channel arrangement (3) and the respective cold fluid channel arrangement ( 4) arranged thermoelectric element (5), - wherein the hot fluid channel arrangement (3) a hot fluid (6) in a hot fluid direction (7) and by the cold fluid channel arrangement (4) a cold fluid (8) at least partially in one of the hot fluid direction (7) wherein the heat exchanger (1) has a tensioning arrangement (12) with a first clamping plate (13a) and with a second clamping plate (13b), and wherein the first clamping plate (13a) and the second Clamping plate (13b) on opposite stacking surfaces (14a, 14b) of the heat exchanger stack (2) are arranged and the heat eübertragerstapel (2) in one of the hot fluid direction (7) and the cold fluid direction (9) clamp substantially orthogonal stacking direction (15); characterized in that the tensioning arrangement (12) has a first frame plate (16a) and a second frame plate (16b), wherein the first frame plate (16a) and the second frame plate (16b) are arranged on opposite frame surfaces (17a, 17b) of the heat exchanger stack (16b). 2), and - that the first frame plate (16a) and the second frame plate (16b) clamp the heat exchanger stack (2) with a hot fluid outlet (10a) and with a hot fluid inlet (10b) in the hot fluid direction (7). Heat exchanger after Claim 1 characterized in that the hot fluid outlet (10a) on the first frame plate (16a) and the hot fluid inlet (10b) on the second frame plate (10b) are integrally formed. Heat exchanger after Claim 1 or 2 , characterized in that the first frame plate (16a) and the second frame plate (16b) with the interposed heat exchanger stack (2) by at least one clamping element (18) are interconnected. Heat exchanger after Claim 3 , characterized in that the at least one clamping element (18) is a threaded rod or a clamp or a tension belt. Heat exchanger according to one of the preceding claims, characterized in that the first clamping plate (13a) and the second clamping plate (13b) on the first frame plate (16a) and on the second frame plate (16b) are fixed non-positively or positively and thereby a Rahmengurt (19 ) to form the heat exchanger stack (2). Heat exchanger according to one of the preceding claims, characterized in that the tensioning arrangement (12) has at least one sealing plate (20a, 20b) arranged between one of the frame surfaces (17a, 17b) of the heat exchanger stack (2) and the respective frame plate (16a, 16b). the tensioning arrangement (12) is arranged. Heat exchanger according to one of the preceding claims, characterized in that a cold fluid outlet (11a) with at least one of the cold fluid channel arrangements (4) by a sealing element and / or a cold fluid inlet (11b) with at least one of the cold fluid channel orders (4) by a sealing element (11) fluidly conductive are connected. Heat exchanger according to one of the preceding claims, characterized in that the bracing arrangement (12) has at least one pressure plate (21), which abuts one of the stacking surfaces (14a, 14b) of the heat exchanger stack (2) and which to the respective clamping plate (13a, 13b ) Is fixed spaced by at least one spring element (22). Heat exchanger after Claim 8 , characterized in that the spring element (22) is a plate spring, a leaf spring or a compression spring. Heat exchanger after Claim 8 or 9 , characterized in that at least one of the stacking surfaces (14a, 14b) of the heat exchanger stack (2) a cold fluid channel arrangement (4) is arranged and that the pressure plate (21) on the cold fluid channel arrangement (4) is arranged adjacent. Heat exchanger according to one of Claims 8 to 10 , characterized in that the spring element (22) and the pressure plate (21) on the respective clamping plate (13a, 13b) by at least one guide pin (23) and at least one threaded sleeve (24) in the stacking direction (7) are slidably fixed.

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