DE602005002995T2 - Device combining an internal heat exchanger and accumulator for a cycle of an air conditioner - Google Patents

Abstract

The device has an outer cylindrical wall (20) with channels (22) to vertically circulate refrigerant upwards at high pressure and temperature. An annular space (48) is defined between the wall (20) and a cylindrical wall of a refrigerant container (32) to vertically circulate the refrigerant downwards at low pressure and temperature. Heat is exchanged between the refrigerants. Connections for the refrigerant, and for connection to an evaporator and a compressor, are grouped respectively in an upper flange (26) and a lower flange (24). An independent claim is also included for a gas cooler for an air-conditioning circuit circulated by a refrigerant in gaseous phase.

Description

The The invention relates to the field of air conditioning circuits in particular for motor vehicles.

In a conventional one Air conditioning circuit is the coolant, usually a fluorine compound, in the form of two different phases, namely a gaseous and a liquid phase available. The gaseous coolant set in motion by a compressor is compressed in a compressor in a liquid state and subsequently relaxed in a pressure reducer. From there it gets into one Evaporator in which it is converted to the gaseous state, to get to the compressor, etc.

Around attributable to the use of environmentally harmful compounds To avoid disadvantages, has been proposed, the conventional coolant with less harmful coolant, especially by natural Replace compounds such as the carbon dioxide (CO2) with the coolant mostly in gaseous form Condition remains.

It are thus air conditioning circuits have been proposed in which such natural coolants are used, which are present in the supercritical state and with significant higher pressure operated as in the case of conventional air conditioning circuits. In such circuits becomes the gaseous coolant through the compressor to a gas cooler and then into sent a first part of an internal heat exchanger before it passes to a pressure reducer and then an evaporator. At the exit from the evaporator, the coolant reaches an accumulator and flows through a second part of the internal heat exchanger before going to the Return to the compressor returns.

in the internal heat exchanger exchanges the coolant with high pressure and high temperature heat with the same coolant with low pressure and low temperature.

To simplify the construction of such air conditioning circuits, has already been proposed, as in U.S. Patent 6,523,365 taught to form an integrated in an accumulator internal heat exchanger. However, this known device has a certain number of disadvantages. The volume occupied by the internal heat exchanger within the accumulator is relatively large. The diameter of the accumulator is determined by the minimum radius of curvature of the coaxially arranged heat exchanger. The inner wall of the heat exchanger has a low temperature, which causes extensive heat exchange with the environment and results in a loss of system efficiency. In addition, the relatively thick wall of the accumulator has no function other than to be a container for the coolant.

Like in U.S. Patent 6,539,746 It has also been proposed to integrate an accumulator and an internal heat exchanger within the gas cooler. However, this known device has a certain number of disadvantages. The accumulator and the internal heat exchanger form two different components, which are assembled together with the gas cooler, whereby the number of parts is larger.

The Thickness of the wall of the accumulator must be relatively strong in order to be relative size Withstand bursting pressure levels. The wall of the accumulator is in direct contact with the Environment and is located in an area with high air circulation, whereby the heat exchange increases with the environment and leads to a loss of efficiency. The connections for the coolant are at the four corners of the heat exchange module arranged, which leads to elaborate connections.

According to the U.S. Patent 6,189,334 is also known an air conditioning system in which the internal heat exchanger is combined with a compressor and a collector.

In addition, from the U.S. Patent 6,751,983 an air conditioning system is known in which the internal heat exchanger has spirally arranged lines.

The Invention aims to provide a combined device from an internal heat exchanger and an accumulator for an air conditioning circuit through which a coolant flows, to provide that makes it possible overcome the aforementioned disadvantages.

One Another object of the invention is to provide such a device To provide a type whose structure is simple and which allows to pool the coolant connections.

For this purpose, the invention proposes such a combined device of the type defined in the introduction, which comprises a cylindrical outer wall in which a plurality of channels for circulating the coolant at high pressure and high temperature are formed, a lower flange which is a lower Close the end of the cylindrical wall, an upper flange which can close an upper end of the cylindrical wall, access openings for the coolant, which are arranged in the lower and upper flange, a Be container, which is disposed in the space defined by the outer cylindrical wall and the lower and upper flange, a supply of low-pressure, low-temperature refrigerant connected to the container, and a passage for circulating the low-pressure refrigerant and low temperature, which is formed between the cylindrical wall and the container and supplied from the container.

• – sie ermöglicht es, einen Wärmeaustausch zwischen dem Kühlmittel mit niedrigem Druck und niedriger Temperatur am Ausgang des Akkumulators und dem Kühlmittel mit hohem Druck und hoher Temperatur am Ausgang des Gaskühlers durchzuführen, und
• – sie ermöglicht es, für den Akkumulator einen unter Druck stehenden Behälter auszubilden.

The internal heat exchanger therefore has a coaxial structure which is integrated directly in the wall of the accumulator. The wall of the accumulator, which may for example be formed in the form of an extruded profile or a plurality of coaxial tubes, now has a double function:

• It makes it possible to carry out a heat exchange between the low pressure and the low temperature refrigerant at the outlet of the accumulator and the high pressure and high temperature refrigerant at the outlet of the gas cooler, and
• - It makes it possible to form a pressurized container for the accumulator.

The Connections, around the coolant to connect with the evaporator and the compressor are in the upper or lower flange folded, which simplifies the structure.

Of the Term "container" refers to here an element that essentially has an area for separating the Phases for the coolant limited, d. H. around the gaseous Phase and the liquid Phase of this coolant to separate. It is also advantageous that this container also an area for storing the refrigerant in the liquid phase and thus a liquid supply forms.

According to the invention For example, the channels formed in the cylindrical outer wall are preferably parallel.

Of the lower flange and the upper flange form closure elements, around the cylindrical outer wall complete at the bottom and top. The lower or upper Flange is advantageously each with a lower recess provided, which is arranged around the lower and an upper end the cylindrical outer wall take.

According to one embodiment The invention comprises the container a cylindrical inner wall extending from the cylindrical outer wall spaced inwardly to define an annular space, the a passage for circulating the refrigerant with low pressure and low temperature, that in the upper Part with the container and in the lower part with a passage for the discharge of the coolant associated with low pressure and low temperature, the traverses the lower flange.

In this first embodiment The invention may be the annular Room a passage without Obstacles or a direct passage for the circulation of the coolant form with low pressure and low temperature. As a variant can the aforementioned annular Space a means for the heat exchange pick up a spiral Channel between the cylindrical outer wall and the cylindrical To form inner wall. This means for heat exchange, for example, a helically Organ or a helical one Capillary tube, which continues into the container.

In this first embodiment closes advantageously, the cylindrical inner wall to a curved bottom on, which bears against the lower flange.

The cylindrical outer wall is advantageously formed of an extruded profile in which the channels for the Circulate the coolant with high pressure and high temperature are formed.

In a second embodiment invention, the device comprises an extruded profile, the outside channels, the the channels for the Circulating the coolant form with high pressure and high temperature, and inner channels, the the passage for circulating of the coolant form with low pressure and low temperature.

The Supply of coolant with low pressure and low temperature, which connected to the container is advantageously includes means for forming a turbulence in the coolant with low pressure and low temperature, which penetrates into the container, around the gaseous Phase and the liquid Phase of the coolant to separate.

The For example, means which allow the formation of a turbulence may consist of a helical tube, that in the container is arranged, or even consist of means that an eddy current form.

The Device of the invention advantageously comprises a reversing member, to promote one from the coolant transport lubricating oil from the bottom of the container off to the passage for circulation of the coolant to ensure low pressure and low temperature.

Advantageously, the lower comprises Flange an internal passage, which forms an input port, which can be connected to the output of a compressor, and an output port, which can be connected to the input of a gas cooler.

According to the invention is the coolant advantageously carbon dioxide.

Under In another aspect, the invention relates to a gas cooler for a Air conditioning circuit consisting of a refrigerant in gaseous phase is flowing through, with this cooler with a combined device of an internal heat exchanger and an accumulator as defined above.

Of the gas cooler preferably comprises a collector with an inlet opening, at the exit of a compressor through a passage can be connected, which is formed in the lower flange is, and with an exit opening, to an entrance opening the lower flange can be connected.

In the following description, which is given by way of example only is on the attached drawings Referenced, showing:

1 a schematic axial sectional view of a combined according to a first embodiment of the invention device in which also those elements of the air conditioning circuit are shown, to which this device is connected;

2 a detailed axial sectional view of the upper part of one of 1 similar device;

3 a final view of the upper flange of the device of 2 ;

4 an axial sectional view of the lower part of the device of 2 ;

5 a sectional view taken along the line VV of 4 ;

6 a perspective view of the outer wall and the inner wall of the device of 1 to 4 ;

7 one of the 6 similar view in an embodiment;

8th a sectional view of the wall of the device in an embodiment in which the coolant circulates in multiple passes;

9 an axial sectional view of an embodiment in which the coolant coming from the accumulator circulates in a helical tube;

10 a front view of a gas cooler, in which a combined device according to the invention is integrated;

11 one of the 5 similar view in an embodiment;

12 a partial sectional view on an enlarged scale along the line XII-XII of 11 ;

13 one of the 5 similar sectional view in a further embodiment; and

14 a partial sectional view on an enlarged scale along the line XIV-XIV of 13 ;

First, it will open 1 Reference is made, which represents a combined device of an internal heat exchanger and a rechargeable battery, denoted overall by the reference numeral 10 is provided. The device 10 belongs to an air conditioning circuit, which is traversed by a gaseous coolant and in the supercritical state, for example, the carbon dioxide (CO ₂ ) works. In addition to the device 10 the circuit includes a compressor 12 , a gas cooler 14 , a pressure reducer 16 and an evaporator 18 ,

The device 10 includes a cylindrical outer wall 20 , which in the example has a circular cross-section, in which a plurality of channels parallel in the example 22 for circulating the gas cooler 14 coming coolant are formed at high pressure and high temperature. The wall 20 is from an inner surface 20a and an outer surface 20b limited, both being cylindrical. The wall 20 is between a lower flange 24 and an upper flange 26 appropriate. The lower flange 24 is with a lower, here circular depression 28 provided so as to be the lower end of the cylindrical wall 20 receives. Similarly, the upper flange 26 with an upper, here circular depression 30 provided, which is arranged so that it the upper end of the cylindrical outer wall 20 receives.

A container 32 is arranged in the space (cylindrical volume), passing through the cylindrical outer wall 20 and the flanges 24 and 26 is defined. The container 32 simultaneously delimits a region for separating the gaseous and liquid phases of the coolant and a region for storing the coolant in the liquid phase, thus forming a liquid container for collecting the cooling is formed by means of.

This container comprises a cylindrical wall 34 that are coaxial and spaced apart from the outer wall 20 is arranged, and a vaulted ground 36 that is against a top surface 38 of the lower flange 24 is applied. The latter is also outside by a lower surface 40 limited. The wall 34 may be referred to as the "inner wall" of the device insofar as it is from the outer wall 20 spaced inwardly. The wall 34 is by an inner surface 34a and an outer surface 34b limited. The arched floor 36 and the lower flange 24 define an annular channel for the drainage of the coolant, as will be seen below.

The upper flange 26 is through a bottom surface 42 and an upper surface 44 limited. The two flanges are advantageously formed as elaborated blocks.

The cylindrical wall 34 of the container 32 includes an open end 46 located at the small distance d of the lower surface 42 the upper flange is located. So can the interior of the container 32 with an annular passage 48 communicate between the outer wall 20 and the container is enclosed, said passage is designed for the circulation of the refrigerant at low pressure and low temperature.

In the embodiment of the 1 goes the aforementioned passage 48 in the annular space above, between the cylindrical wall 34 the container, which forms an inner wall, and the cylindrical outer wall 20 is limited. This annular space here allows a passage without obstacles or a direct passage for circulating the refrigerant at low pressure and low temperature.

The annular space thus formed is in the lower part with a passage 50 connected to the drain of the low pressure and low temperature coolant, which is the lower flange 24 between its surfaces 38 and 40 passes through and thus an exit opening 52 forms. The passage 50 opens in the upper part in the aforementioned annular channel, which is between the curved bottom 36 and the upper surface 38 of the lower flange 24 is formed.

The upper flange 26 includes a passage 54 for the supply of the coolant at low pressure and low temperature. This passage 54 is designed as a bore through the flange 26 goes through and on its surfaces 42 and 44 empties. The passage 54 forms an entrance opening 56 for the low pressure and low temperature coolant coming out of the evaporator 18 comes.

In the lower part of the passage 54 is an end 58 a pipe 60 pushed in, helical inside the container 32 is arranged and with one end 62 concludes. This helical tube 60 forms means for forming turbulence within the low pressure, low temperature refrigerant flowing into the container. This allows the separation of the gaseous and liquid phase of the coolant. The thus separated liquid phase accumulates in the container 32 , wherein the liquid level is denoted by the reference numeral N in 1 while the gaseous phase is the passage 48 reached to the device 10 over the drain passage 50 to leave.

In addition, the coolant promotes an oil that is necessary to lubricate the compressor 12 to ensure. This lubricating oil runs out of the container 32 about a reversal organ 64 from, which is designed here as a capillary tube, the lower end 66 reaches to the bottom of the container while the rod-shaped upper end 68 in the upper part of the passage 48 empties.

The upper flange 26 also includes an exit port 70 that with the upper recess 30 connected to the input of the pressure reducer 16 can be connected.

The lower flange 24 has an opening 72 on that into the lower recess 28 opens and with the exit of the gas cooler 14 can be connected. In addition, the lower flange 24 an internal passage 74 on, which is formed of two right-angled holes, which are interconnected and on the lower surface 40 of the flange 24 and on a side surface 76 of the flange open to an inlet opening 78 connected to the output of the compressor 12 can be connected, and an output port 80 to form with the entrance of the gas cooler 14 can be connected. The openings 72 and 80 of the flange 24 are arranged close to each other and open on the side surface 76 To connect or solder the flange to the gas cooler 14 to facilitate.

The thus-equipped circuit of the device 10 works as follows. That from the compressor 12 incoming gaseous coolant passes through the internal passage 74 of the flange 24 to the gas cooler 14 to reach. The coolant then reaches the lower recess 28 and then circulates vertically from bottom to top in the channels 22 the Wall 20 as shown by the arrows. Subsequently, the coolant reaches the upper recess 30 and crosses the one after the other Pressure reducer and the evaporator 18 to the entrance opening 56 to reach. The coolant then reaches the container 32 over the helical tube 60 , Due to the resulting vortex movement separate the liquid and gaseous phase of the coolant. The gaseous coolant then reaches the passage 48 to the drain passage 50 to arrive and to the entrance of the compressor 12 to return. The lubricating oil in turn flows from the bottom of the container over the capillary tube 64 and is then fed into the coolant to allow lubrication of the compressor.

Due to this structure, heat exchange is obtained between the high-pressure-high-temperature refrigerant perpendicularly from the bottom to the top of the channels 22 the Wall 20 circulates, and the low-pressure, low-temperature coolant perpendicularly from top to bottom in the annular space 48 circulates between the wall 20 and the cylindrical wall 34 the container is defined. This makes it possible to obtain an integrated structure with a small footprint and weight and a minimum of connections, the latter all at the flanges 24 and 26 are merged.

In addition, the thermal performance is increased by the heat exchange between the accumulator (ie the container 32 ) and the environment is reduced. There is also a reduction in possible losses due to the reduced number of connections.

In the embodiment of 1 is the cylindrical outer wall 20 advantageously as an extruded profile, preferably made of metal, in which the parallel channels 22 are formed. In this example, the container is 32 as a separate component, in this case designed as a container with a curved bottom, within this wall 20 is included. As can be seen further, however, further embodiments are conceivable.

The 2 is a detailed view of an upper part of one of 1 corresponding device 10 , The elements with those of 1 are common, are provided with the same reference numerals. There is also a hole 82 to see, which is executed as blind hole, which at the upper surface 44 of the upper flange 26 empties. This hole is provided for the attachment of a counter flange (not shown) via a screw or the like.

In 3 , which is a final view of the upper flange 26 is, are also the hole 82 and the openings 56 and 76 to see.

The 4 is a detailed view of the lower part of the combined device of 2 , The elements with those of 1 are common, are provided with the same reference numbers. The lower flange 24 also has a hole 84 on, which is designed as a blind hole on the lower surface 40 of the flange 24 empties. This hole is provided for the attachment of a counter flange (not shown) via a screw or the like.

The 5 is a horizontal sectional view of the device of 4 , It shows in detail the structure of the cylindrical wall 20 , which is designed as an extruded profile and the channels 22 Are defined. It can also be seen that the container 32 is designed as a separate component, which is coaxial within the wall 20 is included.

The 6 is a perspective view showing the coaxial arrangement of the outer wall 20 and the inner wall 32 of the container 32 shows.

In the embodiment of the 7 the device has an extruded profile 86 on the one hand, external channels 22 which form the parallel channels for circulating the coolant at high pressure and high temperature, and internal channels 88 comprising the passage for circulating the low-pressure, low-temperature refrigerant. The channels 22 are arranged in a circular shape, one more, through the channels 88 surrounds formed circular design. In this way, the high pressure, high temperature coolant circulates against the low pressure, low temperature coolant flow.

In the previous embodiments, the coolant circulates in a single pass both in the channels 22 as well as in transit 48 or in the channels 88 , It is still conceivable to circulate the coolant in several passes. As in 8th shown is the outer wall 20 in two parts, namely one part 20A for circulating the coolant in one direction and one part 20B split for circulating the coolant in a different direction. Similarly, the passage 48 in two parts, namely one part 48A according to the part 20A and a part 48B according to the part 20B divided up. The coolant may, for example, from top to bottom in the part 20A and from bottom to top in the part 20B , from bottom to top in part 48A and from top to bottom in the part 48B circulate. This, of course, requires forming the recesses of the flanges, to allow each time a return of the coolant.

It is now on the 9 Cover ge taken, which represents a further embodiment, in which the annular space between the outer wall 20 and the wall 34 of the container 32 a means for heat exchange 90 , for example, a helical around the wall 34 wrapped flat metal wire takes up a helical channel 91 between the walls 20 and 34 to build. As a variant, it may be a helically wound capillary tube, which continues into the container to the above-mentioned tube 64 to build. The desired goal is the passage cross section in the annular cross section 48 reduce to cause an increase in the flow speed of the coolant with low pressure and low temperature. This increase in speed has a positive effect on the heat exchange coefficient between the wall 20 and the coolant.

The 10 shows a gas cooler 14 that with a combined device according to the invention 10 Is provided. The gas cooler 14 includes one between two tubular collectors 94 and 96 attached bundles 92 which can be arranged vertically. The combined device 10 is substantially perpendicular and coaxial along the collector 94 built-in. As in the 1 and 4 includes the lower flange 24 an entrance opening 72 and an exit port 80 , The exit opening 80 can with an entrance opening 98 of the collector 94 for connecting the collector to the outlet of the compressor 12 through the passage formed in the lower flange 74 be connected through. The collector 94 also includes an exit port 100 connected to the entrance opening 72 the lower flange can be connected to the lower recess 28 empties. In the 10 are also the openings 52 and 78 of the lower flange connecting to the compressor 12 allow, as well as the openings 70 and 56 of the upper flange, showing the connection with the pressure reducer 16 and the evaporator 18 enable.

In the embodiment of the 11 and 12 has the cylindrical wall 34 of the container 32 an outer surface 34b with a slightly wavy shape to form waves against the inner surface 20a the Wall 20 be pressed, and thus channels 102 for circulating the refrigerant at low pressure and low temperature. These channels 102 thus together form the aforementioned passage 48 , The container 32 is thus in thermal contact with the profile 20 and the exchange surface in contact with the low pressure, low temperature coolant is substantially increased. In addition, the inner surface 34a the Wall 34 with an insulating coating 104 coated to transfer the heat from the wall 20 to in the container 32 reduce refrigerant contained in liquid form.

The 13 and 14 illustrate a further variant in which a cylinder 106 with corrugated surface between the inner surface 20a the Wall 20 and the outer surface 34b the Wall 34 is used. The corrugated cylinder 106 is on the wall 20 soldered, both of which are formed for example of a material of aluminum base. The container 32 On the other hand, it is made of a material such as steel, which is not easy to solder with aluminum to withstand the soldering temperature. In this embodiment, the container 32 not with an inner coating 104 Mistake.

The The invention is not limited to the embodiments described above by way of example limited and extends to other variants.

Claims (19)

Combined device consisting of an internal heat exchanger and an accumulator for an air-conditioning circuit, through which a coolant flows, characterized in that it has a cylindrical outer wall ( 20 ), in which a plurality of channels ( 22 ) are formed for circulating the coolant at high pressure and high temperature, a lower flange ( 24 ), which has a lower end of the cylindrical outer wall ( 20 ), an upper flange ( 26 ), which has an upper end of the cylindrical outer wall ( 20 ), access openings ( 52 . 78 ; 56 . 70 ) for the coolant, which are arranged in the lower and upper flange, a container ( 32 ), in which through the cylindrical outer wall ( 20 ) and the lower and upper flange defined space, a supply ( 54 ) with low-pressure, low-temperature coolant connected to the container ( 32 ) and a passage ( 48 ; 88 ; 90 ) for circulating the low pressure, low temperature coolant between the outer cylindrical wall ( 20 ) and the container ( 32 ) is formed and supplied from the container. Device according to claim 1, characterized in that the container ( 32 ) limits a region for phase separation for the coolant and a region for storing the coolant in the liquid phase. Device according to one of claims 1 and 2, characterized in that in the cylindrical outer wall ( 20 ) formed channels ( 22 ) are parallel to each other. Device according to one of claims 1 to 3, characterized in that the lower flange ( 24 ) and upper flange ( 26 ) each with a lower one ( 28 ) or upper ( 30 ) Are provided, which is arranged around the lower or an upper end of the cylindrical outer wall ( 20 ). Device according to one of claims 1 to 4, characterized in that the container ( 32 ) a cylindrical inner wall ( 34 ) formed by the cylindrical outer wall ( 20 ) is spaced inwardly to form an annular space ( 48 ), which forms a passage for the circulation of the low-pressure and low-temperature coolant, which in the upper part with the container ( 32 ) and in the lower part with a passage for the drain ( 50 ) is connected to the low pressure and low temperature coolant, the lower flange ( 24 ). Apparatus according to claim 5, characterized in that the annular space ( 48 ) forms a passage without obstacles for circulating the low-pressure, low-temperature refrigerant. Apparatus according to claim 5, characterized in that the annular space ( 48 ) a means for heat exchange ( 90 ; 64 ) to form a spiral channel between the cylindrical outer wall ( 20 ) and the cylindrical inner wall ( 34 ) to build. Apparatus according to claim 7, characterized in that the means for heat exchange a helical member ( 90 ). Apparatus according to claim 7, characterized in that the means for heat exchange, a helical capillary tube ( 64 ), which is in the container ( 32 ) continues. Device according to one of claims 5 to 9, characterized in that the cylindrical inner wall ( 34 ) of the container to a curved bottom ( 36 ), which against the lower flange ( 24 ) is present. Device according to one of claims 5 to 10, characterized in that the cylindrical outer wall ( 20 ) is formed of an extruded profile in which the channels ( 22 ) are formed for circulating the coolant at high pressure and high temperature. Device according to claim 1, characterized in that it has an extruded profile ( 86 ), the outer channels ( 22 ), which form the channels for circulating the coolant at high pressure and high temperature, and internal channels ( 88 ) which form the passage for circulating the low pressure, low temperature coolant. Device according to one of claims 1 to 12, characterized in that the supply ( 54 ) with low-pressure, low-temperature coolant connected to the container ( 32 ), means ( 60 ) for forming a turbulence in the low-pressure, low-temperature refrigerant which enters the container to separate the gaseous phase and the liquid phase of the refrigerant. Apparatus according to claim 13, characterized in that the means for forming a turbulence a helical tube ( 60 ) contained in the container ( 32 ) is arranged. Device according to one of claims 1 to 14, characterized in that it is a reversing member ( 64 ) for conveying a lubricant oil transported by the coolant from the bottom of the container ( 32 ) to the passage ( 48 ) for circulating the refrigerant at low pressure and low temperature. Device according to one of claims 1 to 15, characterized in that the lower flange ( 24 ) an internal passage ( 74 ) having an entrance opening ( 78 ) connected to the output of a compressor ( 12 ) and an exit port ( 80 ) to the entrance of a gas cooler ( 14 ) can be connected. Device according to one of claims 1 to 16, characterized that the coolant is carbon dioxide is. Gas cooler for an air-conditioning circuit through which a gaseous phase refrigerant flows, characterized in that it is provided with a combined device ( 10 ), which consists of an internal heat exchanger and a rechargeable battery according to one of claims 1 to 17. Gas cooler according to claim 18, characterized in that it is a collector ( 94 ) with an entrance opening ( 98 ) connected to the outlet of a compressor ( 12 ) through a passage ( 74 ) which can be connected in the lower flange ( 24 ) is arranged, and with an exit opening ( 100 ), which are connected to an inlet opening of the lower flange ( 24 ) can be connected.