EP3620727A1 - Condenser with insert for an air conditioning system, in particular for a motor vehicle - Google Patents

Abstract

A condenser (10) for an air conditioning system, in particular for a motor vehicle, comprises a first and a second manifold (12, 14) and a plurality of heat exchanger channels (16) arranged one above the other, which extend between the two manifolds (12, 14). The condenser (10) further comprises an inlet (20) for essentially gaseous refrigerant, which is arranged on one of the two manifolds (12, 14), and an outlet (22) for essentially liquid refrigerant, which is located on one of the two manifolds (12, 14) is arranged. One of the two manifolds (12, 14) is provided with an insert (26). The insert part (26) defines a flow profile in the header pipe (12), which distributes the refrigerant over a large number of the heat exchanger channels (16).

Description

The invention relates to a condenser with a first and a second manifold, a plurality of heat exchanger channels arranged one above the other, which extend between the two manifolds, an inlet for essentially gaseous refrigerant, which is arranged on one of the two manifolds, and an outlet for essentially liquid Refrigerant, which is arranged on one of the two header tubes, one of the two header tubes being provided with an insert.

Such a condenser is part of a refrigerant circuit as used for a vehicle air conditioning system. Such air conditioning systems are also known for motor vehicles under the name HVAC. The essential components of such an air conditioning system are a compressor, the condenser and an evaporator.

The function of the condenser is to extract heat from the gaseous refrigerant so that it condenses. For this purpose, the refrigerant is passed through the heat exchanger channels, which are surrounded by ambient air on the outside.

Due to the functioning of the condenser and the usual flow paths, the inlet and the outlet for the refrigerant are usually arranged at a distance from one another. In a simple example, the refrigerant inlet is on one of the manifolds and the refrigerant outlet is on the other manifold. When the inlet and the outlet are on the same manifold, the inlet is usually located at one end, while the outlet is at the other end (e.g. up and down).

In view of the comparatively narrow installation space for such capacitors, however, it may be necessary to arrange the inlet and the outlet at other locations than is sensible in terms of fluid mechanics and / or thermodynamics. Up to now, an external auxiliary line ("jumper line") was usually used for this purpose, one at one end Forms the connection point for the corresponding refrigerant line and the other end leads to the actual inlet or outlet. However, this solution has the disadvantage that the overall space required for the capacitor is increased.

From the DE 10 2016 122 310 A1 is known a condenser of the type mentioned, in which one of the manifolds is provided with an insert which defines a flow channel. The flow channel is connected at one end to the refrigerant inlet and at the other end by means of an overflow opening to the interior of the header. The integration of the otherwise externally arranged additional line ("jumper line") into the interior of a header pipe, which is achieved in this way, increases the flexibility when connecting the condenser to a refrigerant line without increasing the installation space requirement.

The object of the present invention is to improve the flow conditions in the condenser.

This object is achieved by a capacitor having the features of claim 1. Advantageous and expedient refinements of the capacitor according to the invention are specified in the subclaims.

The condenser according to the invention for an air conditioning system, in particular for a motor vehicle, comprises a first and a second manifold as well as a plurality of heat exchanger channels arranged one above the other, which extend between the two manifolds. The condenser further comprises an inlet for essentially gaseous refrigerant, which is arranged on one of the two manifolds, and an outlet for essentially liquid refrigerant, which is arranged on one of the two manifolds. One of the two manifolds is equipped with an insert. The insert defines a flow pattern in the header pipe, which distributes the refrigerant over a large number of the heat exchanger channels.

As already indicated above, in the known condensers the externally arranged additional line ("jumper line") or the flow channel additionally created by means of an insert part ensures that the refrigerant is directed to a specific point in a collecting pipe and on the Way there does not enter adjacent heat exchanger channels in order in this way to specify a specific flow of the refrigerant through different groups of heat exchanger channels in the condenser.

In the condenser according to the invention, on the other hand, an insert is provided which defines a flow pattern in the header pipe, which causes the refrigerant to be distributed over a large number of heat exchanger channels. So no additional flow path should be created, but a targeted - ideally as even as possible - distribution of the refrigerant over a large number of heat exchanger channels is created.

A targeted distribution of the refrigerant within a header pipe of the condenser is important, since a large number of heat exchanger channels arranged one above the other typically results in the case that less refrigerant flows through some of the heat exchanger channels than through others. In particular, in the heat exchanger channels that are far away from the refrigerant inlet of the header pipe, the flow is less than in those closer to the refrigerant inlet. This disadvantageous flow behavior is avoided in the condenser according to the invention. Thanks to the insert part provided according to the invention, which ensures a targeted distribution of the refrigerant over the large number of heat exchanger channels, a similar flow can be achieved through all of these channels. As a result, the pressure loss in the condenser is reduced since more refrigerant can flow through the heat exchanger channels in the same time. This means that more refrigerant is supplied to the cooling system during this time, so that the efficiency of the condenser is increased.

The invention is particularly suitable for condensers in which only a single change of flow direction of the refrigerant is provided. In such condensers, the refrigerant flows through a first group of heat exchanger channels from the first into the second header and then through a second group of heat exchanger channels from the second into the first header. The insert supports the distribution of the refrigerant to one of the heat exchanger channel groups. In principle, an insert can also be arranged in the other collecting tube, in order to include the Support distribution of the refrigerant to the other heat exchanger channel group.

The insert part provided according to the invention preferably has a plurality of geometric structures which influence the flow of the refrigerant in the header in the desired manner. Such structures can e.g. B. certain obstacles, openings, guide or guide sections, etc.

According to a preferred embodiment of the invention, the insert has a first side wall facing the heat exchanger channels, in which a plurality of outlet openings are formed. The outlet openings ensure that only a certain amount of the refrigerant reaches the adjacent heat exchanger channels at predetermined points, while the remaining portion of the refrigerant is supplied to other heat exchanger channels.

The outlet openings are preferably elongated, the longitudinal extension of the outlet openings running in the direction of the arrangement of the heat exchanger channels one above the other. It has been shown that such a shape of the outlet openings is advantageous for a uniform distribution of the refrigerant.

The outlet openings preferably have a length in the range from 5 mm to 15 mm, preferably 10 mm, and a width in the range from 1 mm to 10 mm, preferably 5 mm.

The insert preferably has a second side wall facing away from the heat exchanger channels, which is interrupted by a recess.

An open section is preferably formed between an upper end of the first side wall and an upper edge of the recess provided in the second side wall.

In order to discharge a sufficient amount of refrigerant into heat exchanger channels arranged further up, a design in which the open section is elongated has proven to be advantageous, the longitudinal extent of the open section running in the direction of the stacking of the heat exchanger channels.

The open section preferably has a length in the range from 30 mm to 70 mm, preferably 50 mm, and a width in the range from 5 mm to 20 mm, preferably 12.5 mm.

According to a preferred configuration of the insert part, it has an inclined transition section which extends from a lower edge of the recess provided in the second side wall in the direction of the heat exchanger channels and merges into the first side wall. The transition section forms an inclined guide surface for the refrigerant, which slows down the flow only insignificantly.

In this transition section, an oil separation opening can be formed, through which at least a substantial part of the oil, which is transported into the condenser with the gaseous refrigerant, can be separated immediately and can thus be led to another location in the condenser so that it is the condenser again as quickly as possible leaves. Overall, there is less oil in the condenser, and accordingly more oil is available to lubricate the compressor. It is best to arrange the transition section with the oil separation opening in the immediate vicinity of the refrigerant inlet so that the oil can be removed there immediately from the further flow path of the gaseous refrigerant. The oil separation opening preferably has a surface area in the range from 0.75 mm ² to 9 mm ² , preferably 5 mm ² to 7.5 mm ² .

As mentioned above, the invention is particularly suitable for condensers in which two groups of heat exchanger channels are provided, the refrigerant flowing from the first header pipe through a first heat exchanger channel group in the direction of the second header pipe and through a second heat exchanger channel group in the opposite direction. The two groups, more precisely the access areas in the respective header pipe to the inlet openings of the two heat exchanger channel groups, must be separated from one another, for which purpose a simple partition plate is usually used. In this case, in the condenser according to the invention, the inlet openings of the plurality of heat exchanger channels, over which the refrigerant is distributed through the insert part, are arranged in a region which differs from a lower end of the header extends up to the divider in the header.

According to a preferred embodiment of the insert, it has an elongated shape and extends from the lower end of the collecting pipe to the separating plate in the collecting pipe.

The insert can be firmly connected to a cover, e.g. B. by clinching. The cover can in turn be tightly connected to the manifold, e.g. B. by soldering. In this way, a complete, externally sealed refrigerant distributor with the functionality according to the invention can be produced from a few components.

• Figur 1 einen erfindungsgemäßen Kondensator in einer geschnittenen Seitenansicht;
• Figur 2 eine erste perspektivische Ansicht des Einlegeteils des Kondensators aus Figur 1;
• Figur 3 eine zweite perspektivische Ansicht des Einlegeteils; und
• Figur 4 eine perspektivische Teilansicht einer Baugruppe aus Einlegeteil und Abdeckung.

Further features and advantages of the invention will become apparent from the following description and from the accompanying drawings, to which reference is made. The drawings show:

• Figure 1 a capacitor according to the invention in a sectional side view;
• Figure 2 a first perspective view of the insert part of the capacitor Figure 1 ;
• Figure 3 a second perspective view of the insert; and
• Figure 4 a partial perspective view of an assembly of insert and cover.

In Figure 1 A condenser 10 is shown, which is part of a refrigerant circuit of a motor vehicle air conditioning system.

The condenser 10 has a first header pipe 12, a second header pipe 14 and a plurality of heat exchanger channels 16 arranged one above the other, each of which extends between the first and the second header pipes 12, 14.

A dryer bottle 18 is attached to the second collecting pipe 14.

The first header pipe 12 is here provided with an inlet 20, through which refrigerant is supplied to the condenser 10 in the gaseous state.

An outlet 22 is also attached to the first header pipe 12 through which the refrigerant is discharged in the (at least for the most part) liquid state.

In Figure 1 arrows A and B show the flow paths of the refrigerant through the condenser 10. It can be seen that the refrigerant not only enters the heat exchanger channels 16 at the level of the refrigerant inlet 20, but is also distributed over a large area to a large number of heat exchanger channels 16. In the exemplary embodiment shown, this area extends from the lower end of the first header pipe 12 up to a separating plate 24.

A specially shaped insert 26, which is arranged in the interior of the collecting tube 12 and which is arranged in the inside of the header tube 12, ensures a uniform distribution of the refrigerant to the plurality of heat exchanger channels 16 Figures 2 and 3 is shown separately.

The insert 26 has an elongated shape. In the in Figure 1 In the illustrated embodiment, the insert part 26 extends from the lower end of the collecting tube 12 to the separating plate 24. More precisely, the lower end of the insert part 26 is arranged just below the refrigerant inlet 20, while the upper end is located at approximately three quarters of the height of the condenser 10.

The insert 26 has and a first side wall 28 facing away from the refrigerant inlet 20 and facing the heat exchanger channels 16 and a second side wall 30 facing the refrigerant inlet 20 and facing away from the heat exchanger channels 16.

Two edges 32, 34 rise from the longitudinal edges of the second side wall 30 in the direction of the heat exchanger channels 16. The second side wall 30 is recessed over a larger area. In the exemplary embodiment shown, this recess 36 extends from the height of the refrigerant inlet 20 to approximately one third of the height of the condenser 10.

An inclined transition section 38 extends from the lower edge of the recess 36, that is to say approximately at the level of the refrigerant inlet 20, in the direction of the heat exchanger channels 16. The transition section 38 merges into the first side wall 28, which runs parallel to the second side wall 30.

However, the first side wall 28 extends only to a height which is less than the height of the upper edge of the recess 36. An open section 40 thus remains between the upper end of the first side wall 28 and the upper edge of the recess 36. The open section In the illustrated embodiment, 40 has a width of approximately 12.5 mm and a height (in the longitudinal direction of the insert 26) of approximately 50 mm.

A plurality of elongated outlet openings 42 arranged one above the other are formed in the first side wall 28. In the exemplary embodiment shown, the outlet openings 42 have a width of approximately 5 mm and a height (in the longitudinal direction of the insert 26) of approximately 10 mm.

In the transition section 38 there is only a small oil separation opening 44. This has an area of the order of about 5 mm ² to 7.5 mm ² .

The refrigerant to be condensed is supplied to the condenser 10 via the refrigerant inlet 20 in a (substantially) gaseous state. Oil carried by the gas collects at the transition section 38 and is discharged downward through the oil separation opening 44 due to the prevailing pressure conditions. The gaseous refrigerant is largely directed upward from the insert 26, with a certain portion of the refrigerant in the lower section of the header tube 12 which is actually blocked by the first side wall 28 through the elongated outlet openings 42 from the insert 26 and into the lower heat exchanger channels 16 can occur.

In the area of the open section 40 and above, the gaseous refrigerant can freely enter the upper heat exchanger channels 16 below the separating plate 24.

Overall, the insert 26 with the elongated outlet openings 42 in the first side wall 28, the interrupted second side wall 30 and the open section 40 results in a largely homogeneous distribution of the refrigerant over the plurality of heat exchanger channels 16 up to the separating plate 24. Because of the uniform distribution of the refrigerant on the plurality of heat exchanger channels 16, the pressure loss of the refrigerant in the condenser 10 is minimized.

In the heat exchanger channels 16, the gaseous refrigerant flows in the direction of arrow A and is cooled in the process. In the second header pipe 14, it flows into the dryer bottle 18 and upwards in order to return in a region of the condenser 10 defined above the separating plate 24 through the heat exchanger channels 16 there in the direction of arrow B back to the first header pipe 12 and thus to the refrigerant outlet 22 to pour.

As the refrigerant cools, the proportion of the liquid phase increases. In the area of the refrigerant outlet 22, the coolant is (at least almost) completely liquid.

The oil contained in the gaseous refrigerant, which is discharged downward through the oil separating opening 44, is carried along by the liquid refrigerant and reintroduced into the refrigerant circuit via the refrigerant outlet 22.

The main advantage of the flow behavior of the refrigerant in the collecting tube 12 achieved with the insert part 26 is that the gaseous refrigerant can be distributed very evenly over a large number of heat exchanger channels 16 without any external add-on parts and without changing the installation space required for the condenser 10.

The manufacture of the insert 26 and the corresponding header 12 is described below.

The starting point is a blank in the form of a rectangular sheet metal blank. The wall thickness of the sheet can be of the order of 0.5 mm. In particular, basically the same material can be used that is also used for the manifold 12 and the other components of the capacitor 10.

The openings, which later form the open section 40, the elongated outlet openings 42 and the oil separation opening 44, are then punched at the two narrow ends of the blank facing away from one another.

The blank is then formed until it is in the Figures 2 and 3 insert 26 shown is formed. The first side wall 28 is thereby

Thermoformed and the blank bent to form the edges 32, 34 in the region of its longitudinal edges.

The insert 26 is then attached to a cover 46, as in FIG Figure 4 shown. The cover 46 is elongated and curved in cross section. The insert 26 is connected to the cover 46 such that a flow channel is formed between the concave side of the cover 46 and the first side wall 28 of the insert 26. However, the flow channel is not closed on the side facing the heat exchanger channels 16 due to the elongated outlet openings 42.

In the exemplary embodiment shown, the cover 46 additionally has a lower section 48, in which the refrigerant inlet 20 is located. Likewise, the cover can have an upper section in which the refrigerant outlet 22 is located.

The insert 26 and the cover 46 can be clipped together.

As the next step, the cover 46 is attached to the manifold 12. The collector tube 12 is provided on its side facing away from the cover 46 with a large number of inlet openings which open into the heat exchanger channels 16. The cover 46 and the manifold 12 are preferably soldered together.

Reference list

10th

capacitor

12th

first manifold

14

second manifold

16

Heat exchanger channels

18th

Dryer bottle

20

Refrigerant inlet

22

Refrigerant outlet

24th

Divider

26

Insert

28

first side wall

30th

second side wall

32

edge

34

edge

36

Recess

38

Transition section

40

open section

42

Outlet openings

44

Oil separation opening

46

cover

48

lower section

Claims (14)

Condenser (10) with a first and a second manifold (12, 14), a plurality of heat exchanger channels (16) arranged one above the other, which extend between the two manifolds (12, 14), an inlet (20) for essentially gaseous refrigerant, the is arranged on one of the two header pipes (12, 14), and an outlet (22) for essentially liquid refrigerant, which is arranged on one of the two header pipes (12, 14), one of the two header pipes (12, 14) with is provided with an insert part (26), characterized in that the insert part (26) defines a flow pattern in the header pipe (12) which causes the refrigerant to be distributed over a plurality of the heat exchanger channels (16). Condenser (10) according to claim 1, characterized in that the insert (26) has a plurality of geometric structures which influence the flow of the refrigerant in the header (12). Condenser (10) according to claim 1 or 2, characterized in that the insert (26) has a first side wall (28) facing the heat exchanger channels (16), in which a plurality of outlet openings (42) are formed. Condenser (10) according to claim 3, characterized in that the outlet openings (42) are elongated, the longitudinal extent of the outlet openings (42) running in the direction of the arrangement of the heat exchanger channels (16) one above the other. Capacitor (10) according to claim 3 or 4, characterized in that the outlet openings have a length in the range from 5 mm to 15 mm, preferably 10 mm, and a width in the range from 1 mm to 10 mm, preferably 5 mm. Condenser (10) according to one of the preceding claims, characterized in that the insert (26) has a second side wall (30) with a recess (36) facing away from the heat exchanger channels (16). Capacitor (10) according to any one of claims 2 and 5 and claim 6, characterized in that between an upper end of the first Sidewall (28) and an upper edge of the recess (36) an open portion (40) is formed. Condenser (10) according to Claim 7, characterized in that the open section (40) is elongate, the longitudinal extent of the open section (40) running in the direction of the stacking of the heat exchanger channels (16). Capacitor (10) according to claim 7 or 8, characterized in that the open section (40) has a length in the range from 30 mm to 70 mm, preferably 50 mm, and a width in the range from 5 mm to 20 mm, preferably 12, 5 mm. Condenser (10) according to one of claims 6 to 9, characterized in that the insert (26) has an inclined transition section (38) which extends from a lower edge of the recess (36) in the direction of the heat exchanger channels (16) and in the first side wall (28) merges. Capacitor (10) according to claim 10, characterized in that an oil separation opening (44) is formed in the transition section (38), which has an area in the range of 0.75 mm ² to 9 mm ² , preferably 5 mm ² to 7.5 mm ² , has. Condenser (10) according to one of the preceding claims, characterized in that inlet openings of the plurality of heat exchanger channels (16), over which the refrigerant is distributed through the insert part (26), are arranged in a region which extends from a lower end of the header pipe (12) up to a separating plate (24) in the manifold (12). Condenser (10) according to one of the preceding claims, characterized in that the insert (26) has an elongated shape and extends from a lower end of the collecting tube (12) to a separating plate (24) in the collecting tube (12). Capacitor (10) according to one of the preceding claims, characterized in that the insert (26) is fixedly connected to a cover (46), which in turn is tightly connected to the collecting tube (12).

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