DE10352514A1 - Tube-to-tube heat exchanger unit - Google Patents

Abstract

A tube-to-tube heat exchanger for use in an air conditioning system of a motor vehicle has a unitary tube which is divided internally in the longitudinal direction into a first passage and a second passage by a thermally conductive main web. A hot fluid line is connected directly to each end of the first pass without the need for a separate connector. A cold fluid return line is connected directly to each end of the second pass without the need for a separate connector. The fluid lines are connected to the heat exchanger by cold soldering. In one embodiment, the land is substantially planar and the cross-section of both the first passage and the second passage is substantially D-shaped. The heat exchanger may further comprise a support web which extends approximately halfway along the main web perpendicularly therefrom. In a further embodiment, the cross sections of the first and second passageways can be substantially circular, the main web being shaped accordingly. In a further embodiment, the first passage can be substantially circular in cross section and the second passage can be substantially crescent-shaped, the main web being shaped accordingly.

Description

Territory of invention

The invention relates to heat exchangers and particularly concerns heat exchangers for the Use in automotive air conditioning systems.

background the invention

It is known that an internal heat exchangers (also known as a heat exchanger performance in the suction line or simply as a heat exchanger) an air conditioning or cooling system improved by heat transfer between a warm liquid feed line and a cold steam return line is allowed. The expression "internal" means in this Context that heat intem is exchanged within the system, in contrast z. B. to a condenser or evaporator, which heat between the system and the environment. One type of internal heat exchanger that could be used in motor vehicles is a "pipe-in-pipe" or "duplex" heat exchanger, in which there is a fluid line through the center of the heat exchanger extends and a further fluid line surrounds the first fluid line. Such a tube-in-tube heat exchanger is in U.S. Patent Application 200110020786 A1 filed February 23 2001 in the name of Takamatsu et al. However, internal heat exchangers typically not used in motor vehicles because they are in the Usually voluminous. are heavy and / or expensive. The tube-in-tube heat exchanger requires e.g. B. a complicated connector to the through the center of the heat exchanger running fluid line from the surrounding fluid line separate. Such connectors are usually relatively large, heavy, expensive, difficult to install, and they typically cause a significant increase in pressure loss in the suction line, which z. B. occurs when fluids around corners or edges move. Such pressure drops reduce performance of the air conditioning system (or wherever the heat exchanger is arranged). In extreme cases can be where the pressure loss in the suction line is particularly significant is the efficiency of the air conditioning system may be worse than if it were in the system a heat exchanger entirely would be omitted.

In view of the above, it would be desirable a heat exchanger to have the for use in an air conditioning system of a motor vehicle is suitable, installation requirements is customizable, the one simple and inexpensive connection to the cooling or air conditioning system has no excessive weight, Volume or no excessive pressure loss in the suction line.

Summary the invention

According to a first aspect, supplies the invention a tube-to-tube heat exchanger unit, in particular for the Use in an air conditioning system of a motor vehicle, the unit being a unitary heat exchanger with a pipe has that through a main web internally in the longitudinal direction divided into a first pass and a second pass is, the main web is thermally conductive; with a first pair of fluid lines and a second pair of fluid lines; one line of the first pair of fluid lines directly with one end of the first passage is connected and the other line the first pair of fluid lines directly to the other end of the first passage is connected and a line of the second Pair of fluid lines connected directly to one end of the second passage and the other line of the second pair of fluid lines is directly connected to the other end of the second pass.

The invention could be used in applications over the Context of motor vehicles can be used in a virtually unlimited range of applications where heat exchange necessary or desirable is.

Different embodiments can be advantageous the present invention, the use of a heat exchanger in a motor vehicle allow that is easy to manufacture and / or easy to bend is to adapt it to the installation requirements, and / or the simple and inexpensive with a cooling or air conditioning system can be connected and / or no significant weight, volume or there is no pressure loss in the suction line.

Summary of the drawings

Preferred embodiment of the invention now with reference to the attached Described drawings in which:

1 FIG. 10 is a schematic view of a heat exchanger unit shown within a representative air conditioning system of a motor vehicle;

2a FIG. 3 is a perspective view (not to scale) of one end of a heat exchanger in accordance with an embodiment of the present invention, with directly connected fluid lines extending from the heat exchanger;

2 B a perspective view of the heat exchanger and the fluid lines 2a is from the other end;

2c a sectional view of the heat exchanger 2a in the longitudinal direction;

2d a sectional view along lines 2d - 2d in 2c is;

2e a sectional view along lines 2e - 2e in 2c is;

3a 5 is a sectional view of a heat exchanger in accordance with another embodiment of the present invention;

3b Figure 3 is a sectional view of a heat exchanger in accordance with yet another embodiment of the present invention; and

3c 5 is a sectional view of a heat exchanger in accordance with yet another embodiment of the present invention.

detailed Description of the preferred embodiments

Regarding 1 is a schematic view of a representative air conditioning system 10 of a large motor vehicle shown for illustration purposes. In this example, a coolant leaves 12 a capacitor 24 as high pressure liquid and flows through an internal heat exchanger (IHX) 18 and then through a thermal expansion valve 20 and a rear additional module evaporator 22 therethrough. The coolant 12 leaves the rear additional module evaporator 22 as low pressure steam and flows through the IHX 18 and then through an accumulator 24 and by a compressor 26 back through. The refrigerant leaves the compressor 26 as high pressure steam and flows through the condenser 14 therethrough.

If the coolant 12 the capacitor 14 leaves, in this embodiment it flows along two different paths. One way, as mentioned above, is through the IHX 18 therethrough. The other way is through a nozzle tube 30 through and then through a front module evaporator 32 through where the brine 12 emerges as low-pressure steam and then, as mentioned above, through the accumulator 24 flows through.

Regarding 2a is the IHX 18 shown in a perspective view (not to scale) from one end, with an outgoing line 34 for a warm fluid (in this example a liquid) and a return line 36 for a cold fluid (a vapor in this example) from the other end of the IHX 18 extend from. 2 B represents the IHX 18 out 2a in a perspective view from the other end. Views in cross section are in the 2c (along a longitudinal axis), in 2d (across the IHX 18 ) and in 2e (across the fluid lines 34 . 36 , with a view of the IHX 18 ) shown. The IHX 18 is a generally cylindrical tube 38 with an internal, thermally conductive, generally planar bridge 42 which covers the inside surface of the IHX 18 in two passes 44 . 46 divided.

The 2a and 2d show that in a cross section through the width of the IHX 18 the jetty 42 two essentially large D-shaped passages 44 . 46 generated. end up 48 . 50 the hot liquid supply line 34 or the cold steam return line 36 are shaped to go into the passageways 44 respectively. 46 fit. Although in the 2a . 2 B and 2c the hot liquid supply line 34 and the cold steam return line 36 are only depicted as being from one end of the IHX 18 would extend in operation a further hot liquid supply line (not shown) and a further steam return line (not shown) from the other end of the IHX 18 extend in a similar way as in 1 is indicated. The combination of the direct with the instructions 34 and the return lines 36 connected IHX 18 can be referred to as a heat exchanger unit.

The IHX 18 is preferably a single or unitary piece of material formed by extrusion. Since the purpose of a heat exchanger is then to transfer heat, the material should be thermally conductive. The IHX 18 is preferably made of aluminum in view of its cost, weight, thermal conductivity and ability to be bent. Other materials that could be used include steel, stainless steel, copper, an INCONEL ^™ material, or plastic.

The ends 48 . 50 the hot liquid supply line 34 and the cold steam return line 36 are formed by one of many methods known to those skilled in the art to be in the passageways 44 respectively. 46 of the IHX 18 sit. One such method involves the use of a machine (not shown) that strikes the end of a fluid line with a shaping iron so that the desired shape is created.

The ends 48 . 50 the hot liquid supply line 34 and the cold steam return line 36 are then in the passageways 44 respectively. 46 used and directly connected by cold soldering (not shown). The type of cold soldering material used is somewhat dependent on the material used to manufacture the IHX 18 has been used and is known to those skilled in the art. If e.g. B. the IHX 18 is made of aluminum, then the cold soldering material is preferably a paste of an aluminum alloy, the paste is expected to be a suspension of aluminum in a flux paste. If the IHX 18 is made of copper, then the cold soldering material z. B. be silver phosphorus.

Alternatively, the hot liquid supply line could 34 and the cold steam return line 36 directly with the IHX 18 be directly connected by a notch, each line 34 . 36 on the IHX 18 would be attached through the use of a mechanical force.

Before attaching the hot liquid supply line 34 and the cold steam return line 36 on the IHX 18 becomes the IHX 18 be trained so that this assumes a contour (not shown) which corresponds to that where it is to be installed in a motor vehicle (not shown). The IHX 18 is formed using a method known to those skilled in the art. One such method involves the use of a machine (not shown) around an end or area of the IHX 18 to clamp while another machine (not shown) a different area of the IHX 18 pushes or pulls around the IHX 18 to bend so that the desired shape is created.

As noted above, is 2d a view in cross section of the IHX 18 along the width of the IHX 18 which have a special configuration of the web 42 shows. The cross section can, however, by using z. B. different web configurations can be modified. A possible modification is in 3a shown where the jetty 42 which as a main footbridge 42 can be referred to, is essentially the same as the one described in 2d is shown, wherein a vertical support web 50 added, which is the IHX 18 provides additional support when the IHX 18 is bent. With the in 2d shown embodiment, the entire main web 42 over the length of the IHX 18 extend, and would preferably also extend so far. In the in 3a shown embodiment, the support web ends 50 at positions (not shown) within the tube 38 , which are roughly where the end of the instructions 34 or the return lines 36 to the IHX 18 would be attached, otherwise the support web 50 the instructions 34 or the return lines 36 when pushing into the IHX 18 would hinder while the main walkway 42 over the length of the IHX 18 can extend. The instructions 34 and the return lines 36 would then go to the IHX 18 as described above.

Another variation of a web configuration is in 3b shown. In this embodiment, a pair of fluid lines would likely (though not necessarily) the return lines 36 , With its ends circular (not shown) to be formed in the through the main web 56 generated, substantially circular area 54 to fit through (unless the ends of the return lines 36 in its original form, without the need for modification, in the area 54 would fit). Similar to that related to 3a The embodiment described above extends the support web 58 out 3b not over the length of the pipe 38 , Instead, the support bridge ends 58 at positions (not shown) within the tube 38 , roughly where the ends of the leads 34 (or the return lines 36 , whichever is the case) to the IHX 18 would be attached. In this embodiment, an end portion of each forwarding would 34 then shaped as a crescent, so this into the tube 38 fits. The instructions 34 and the return lines 36 would within the IHX 18 be attached as described above.

Another embodiment is in 3c shown where both the shape of the tube 38 as well as the web configuration differs from those described above. In the in 3c The embodiment shown is the view of the tube 38 in cross-section essentially peanut-shaped, with a main web 62 two circular passages 64 . 66 limited. In this embodiment, the end regions of the outgoing line 34 and the return line 36 be able to modify the passages without modification 64 respectively. 66 of the IHX 18 to fit. The circular profiles of the passageways 64 . 66 However, due to the reduced surface area compared to the web configurations in the other embodiments, they can only provide a limited heat exchange. Also the circular profiles of the passageways 64 . 66 a bending of the IHX 18 restrict in a different plane than in the horizontal plane.

Numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described here. For example, the IHX 18 can be used for other applications within a motor vehicle, although the IHX 18 Above was primarily described for use in an application for air conditioning a motor vehicle, which has a rear additional module and a conventional coolant. For example, the IHX 18 in a vehicle with only one front module or with other refrigerants, such as carbon dioxide or ammonia. In another example, the IHX 18 be used as part of a heat pump or a short cycle system for warming up or extracting heat from the engine coolant to produce heat for a passenger compartment of the motor vehicle. It could also be used to cool engine, transmission, or axle / propshaft fluids. In addition, the IHX 18 be used in applications beyond the context of automobiles where heat exchange is necessary or desirable. For example, the IHX 18 in chemical process engineering or wherever an inexpensive heat exchanger is required. As another example, the IHX 18 are used in domestic water heaters for pools or baths, e.g. B. based on refrigerant cycles, or in water heater systems.

Claims (18)

Tube-to-tube heat exchanger unit, in particular for use in an air conditioning system of a motor vehicle, the unit comprising - a uniform heat exchanger ( 18 ) with a pipe ( 38 ) through a main footbridge ( 42 ; 56 ; 62 ) internally in the longitudinal direction in a first pass ( 44 . 64 ) and in a second round ( 46 ; 66 ) is divided, with the main web ( 42 ; 56 ; 62 ) is thermally conductive; - a first pair of fluid lines ( 34 ) and - a second pair of fluid lines ( 36 ); where a line ( 34 ) the first pair of fluid lines directly with one end of the first passage ( 44 ; 64 ) is connected and the other line ( 34 ) the first pair of fluid lines directly to the other end of the first passage ( 44 ; 64 ) is connected and a line ( 36 ) of the second pair of fluid lines directly with one end of the second passage ( 46 ; 66 ) is connected and the other line ( 36 ) of the second pair of fluid lines directly to the other end of the second passage ( 46 ; 46 ) connected is. The unit of claim 1, in which the first pair of fluid lines ( 34 ) Are hot fluid supply lines and the second pair of fluid lines ( 36 ) Are cold fluid return lines. Unit according to claim 1, in which the main web ( 42 ) is essentially planar. Unit according to claim 1, in which the heat exchanger ( 18 ) is an extrusion product. Unit according to claim 1, in which the heat exchanger ( 18 ) is made of aluminum. The unit of claim 1, in which both the first pass ( 44 ) as well as the second round ( 46 ) are substantially "D" shaped in their end view. A unit according to claim 6, in which one end of each of the hot fluid feed lines ( 34 ) and the cold fluid return lines ( 36 ) are substantially "D" shaped in their end view. The unit of claim 1, in which both the first pass ( 44 ) as well as the second round ( 46 ) is essentially circular in its end view. Unit according to claim 1, in which each of the hot fluid supply lines ( 34 ) and the cold fluid return lines ( 36 ) by cold soldering directly with the heat exchanger ( 18 ) connected is. Unit according to claim 7, in which the heat exchanger ( 18 ) also a support bridge ( 50 ) in the longitudinal direction, which extends from the main web ( 56 ) to the pipe ( 38 ) extends. Unit according to claim 10, in which the main web ( 56 ) and the support bridge ( 50 ) together look essentially T-shaped in an end view. Unit according to claim 11, in which the main web ( 56 ) in the longitudinal direction essentially over the entire length of the tube ( 38 ) extends. A unit according to claim 12, in which the support web is at a distance from each end of the tube ( 38 ) ends with the introduction of hot liquid feed lines ( 34 ) or the cold steam feed lines ( 36 ) in the pipe ( 38 ) to allow. Unit according to claim 1, in which the main web ( 62 ) is essentially arcuate in an end view, the ends of the main web ( 62 ) at positions on an inner circumference of the tube ( 38 ) end in such a way that the first pass ( 64 ) with an essentially crescent shape and the second pass ( 66 ) is generated with an essentially circular shape. Unit according to claim 14, in which the heat exchanger ( 18 ) also a support bridge ( 50 ), which is essentially planar and in an end view about half way through the main web ( 62 ) away from this to the inner circumference of the tube ( 38 ) extends. The unit of claim 15, in which each line ( 34 ) of the first pair of fluid lines in an end view is shaped to match the cross section of the second passage ( 66 ) is adapted, and each line ( 36 ) of the second pair of fluid lines in an end view is shaped to match the cross section of the first passage ( 64 ) is adjusted. Unit according to claim 16, in which the main web ( 62 ) essentially over the entire length of the pipe ( 38 ) extends. Unit according to claim 17, in which the support web ( 50 ) ends at a distance from each end of the heat exchanger in order to introduce the hot liquid feed lines ( 34 ) or the cold steam return lines ( 36 ) in the pipe ( 38 ) to allow.