DE102005021787A1 - Transcritical air-conditioning refrigerant e.g. carbon-di-oxide, treating apparatus for use in e.g. automobile, has flat multi-chamber tube extruded to extend straight over length of vessel - Google Patents

Abstract

The apparatus has a longitudinal vessel connected to a collecting tube of a heat exchanger, and defining a heat exchanger chamber and an accumulator chamber. The chambers extend parallel over a portion of the length of the vessel. A flat multi-chamber tube is extruded to extend straight over the length of the vessel, where refrigerant on one side flows through the tube and refrigerant on another side flows through the vessel. A heat-conducting rib extends around a periphery of the tube, and fills up the remaining cross-section of the heat exchanger chamber.

Description

The Invention relates to a device for treating the refrigerant, circulating in an air conditioning circuit containing: compressor, Gas cooler, Evaporator (heat exchanger) and expansion element and thereby a high pressure side and a low pressure side goes through in which the refrigerant has different temperature, wherein the device is a tube through which flows the one side and arranged in a container is, through which the other side flows to as an intermediate heat exchanger to serve, being in the container an accumulator chamber and a heat exchanger chamber formed is.

This device, which is often referred to as an internal heat exchanger in trans-critical air conditioning circuits, is from the DE 196 35 454 A1 is known and can be considered advanced, because the achievable heat exchange rate meets the requirements and because it also includes a Akkumulatorkammer. However, the fabrication of this device-located in the installation space of the motor vehicle-seems to be rather expensive, since the tubes are deformed as spirals and the insertion of the heat-conducting fins between the turns of the coils could also be complicated.

In the DE 103 22 028 B4 an intermediate heat exchanger was integrated as a coaxial tube in the manifold of the evaporator, creating a very compact design was created, which is apparently also cheaper to produce, but which has no accumulator.

In the German patent DE 199 18 617 C2 were an accumulator and - separately - and an internal heat exchanger combined with the gas cooler, creating a very compact design was created. The accumulator is connected to a manifold of the gas cooler. The inner heat exchanger is located at the top or bottom of the gas cooler, ie parallel to the tubes, and thus directly in the influence of the cooling air, which has a temperature of about 30-40 ° C in summer, whereby the intended effect of the internal heat exchanger is counteracted , The degree of intended cooling of the refrigerant on the high pressure side is somewhat reduced by the relatively high temperature of the cooling air. The inner heat exchanger is also quite expensive to produce. Its connection with the gas cooler also seems to be structurally difficult to carry out.

The The object of the invention is, with other design features a compactness and functionality comparable device to propose, which is cheaper can be produced.

The solution according to the invention in the device according to the preamble of claim 1 by the features in its characterizing part.

Because according to the invention the container containing the tube with the manifold of the heat exchanger, preferably the gas cooler, is connected to a structural unit, wherein the existing in the container Accumulator chamber and the heat exchanger chamber parallel to the manifold and over to extend a substantial portion of the length of the container was considered Compactness achieved a good result. At the same time opens up the cheap Possibility, a dryer and possibly also a filter in the accumulator chamber and / or the heat exchanger chamber of the container to arrange, since the space for This measure is sufficient. The filter and dryer ensure the desired drying and purification (treatment) of the transcritical refrigerant, for example CO2 can be.

Of the Accumulator serves the functionality of the plant, since it contributes to that only vaporous refrigerant reaches the compressor and thereby its proper operation guaranteed.

the does not preclude that the vaporous refrigerant just before leaving the heat exchanger chamber towards the compressor over an opening in the longitudinal wall small amounts of oil and liquid refrigerant supplied become. The refrigerant vapor is at this point in such a state that the feed of oil and liquid refrigerant another cooling through Evaporative cooling entails. The vaporous Condition of the refrigerant The compressor is thereby supported and the refrigerant inlet temperature on the compressor is lowered again. In the case mentioned above The technology needs the refrigerant after the return of the oil one more or less big Climb the slope, what Losses. According to the present invention the return is under Bypassing of the internal heat exchanger made directly into the suction line, creating a cheaper heat transfer is available.

The mentioned tube is preferably an extruded multi-chamber tube, which is essentially straight over a little extends at least a substantial length of the container, whereby, inter alia, the relatively inexpensive production of the device is effected. Preferably, the multi-chamber tube is covered around its entire circumference with the heat exchange rib.

A longitudinal wall is in the container formed the container divided into two parts, namely an accumulator chamber and a Heat exchanger chamber. The longitudinal wall has at least one opening to the refrigerant at one end from the accumulator chamber to flow into the heat exchanger chamber. At the other end of the longitudinal wall is another opening present, over the oil deposited in the accumulator into the refrigerant can get.

In the accumulator chamber can be a desiccant and also a filter to be ordered. An inlet tube is arranged in the accumulator chamber, to the deposition of any existing liquid refrigerant in the low pressure phase support. In or on the insertion tube can the dryer is located and immediately below it can be the filter be arranged.

It a plastic wall can be inserted into the container the unwanted heat transfer between the accumulator chamber and the heat exchanger chamber suppressed. The heat exchange should essentially in the heat exchanger chamber take place because it was specially equipped for it. That leads in total to something higher Temperature differences between the low pressure side and the high pressure side in the heat exchanger chamber itself, resulting in improved heat exchange efficiency.

Of the independent Claim 19 refers to a not with a heat exchanger, preferably the gas cooler, United device, rather, in a suitable place is located in the air conditioning circuit and is particularly inexpensive to produce and a has high activity.

These Device is characterized in that the container as slender, preferably produced by extrusion hollow body with a longitudinal wall or is formed with holders for holding an inserted longitudinal wall, wherein the longitudinal wall at least one opening has to the refrigerant from the accumulator chamber to flow into the heat exchanger chamber, and that the tube as preferably using the same extrusion process made multi-chamber tube is formed, which is characterized by the heat exchanger chamber extends and on all sides with heat exchange ribs is occupied. The device is particularly easy to manufacture and is characterized by its slim design, the contributes to a conventional one Air conditioning and air conditioning with transcritical refrigerant, for example, CO2, with substantially the same space requirements, what a not negligible Advantage for the Automobile manufacturers, who are therefore not forced, their space concepts within a range of automobiles depending on the type of air conditioning system to change. With regard to worldwide different environmental regulations Will you be automobiles for a market with conventional Want to equip air conditioners and for another market with CO2 air conditioners. Following are some embodiments described with reference to the accompanying drawings. In This description is further features and associated Contain benefits that turn out to be particularly important can.

Brief description of the pictures

The 1 shows a longitudinal section through a device according to the invention.

The 2 shows a cross section through the device according to the 1 or 3 ,

The 3 shows a longitudinal section in a preferred embodiment of the invention.

The 4 shows an alternative design in a cross section through the container.

The 5 shows a flat multi-chamber tube in a cross section according to another alternative.

The 6 . 7 and 8th show different versions of the container in cross section.

The 9 - 12 show purely schematically the connection of the device with a heat exchanger, preferably with the gas cooler.

The in the embodiments described devices are preferably for use in air conditioning systems of motor vehicles in approximately vertical arrangement determined.

The apparatus for treating the refrigerant according to the 1 and 3 differs by the arrangement of a filter 23 in the accumulator chamber 21 or in the heat exchanger chamber 22 , They otherwise agree that they have a container 20 with a longitudinal wall 26 which was produced by means of extrusion molding. The longitudinal wall 26 divides the container 20 in the two mentioned chambers 21 . 22 extending in parallel and essentially over the entire length of the container 20 extend. In the accumulator chamber 21 there is a dryer 24 in the this embodiment outside of an insertion tube 25 was arranged. Through the heat exchanger chamber 22 extends a flat multi-chamber tube 10 that with a heat conduction rib 11 equipped, which is the remaining cross-section of the heat exchanger chamber 22 largely filled in order to achieve good results in terms of heat exchange efficiency. Furthermore, in both versions an insulation 50 provided the surface of the container 20 covers. This measure is particularly suitable where temperature influences from the environment on the heat exchange in the container 20 want to avoid. Usually these are too high outside temperatures. The lower-pressure side, cooler refrigerant flows through an opening 40 in the upper lid 80 in the collector's chamber 21 one. To support the accumulator function or the settling of liquid and oil, an insertion tube protrudes 25 in the accumulator chamber 21 into it. In case of 1 this refrigerant flows through a filter basket 25 at the end of the insertion tube 25 , Oil in the refrigerant and residual liquid refrigerant settle in the accumulator chamber 21 down from. The gaseous refrigerant flows above via an inflow opening 31 in the longitudinal wall 26 into the heat exchanger chamber 22 a to pass through the heat conduction rib 11 down towards the exit 41 to get into the wall of the container 20 is arranged. The high-pressure side and warmer refrigerant flows through a channel 70 in the upper lid 80 in the multi-chamber tube 10 A, flows in the multi-chamber tube 10 down to the exit channel 71 in the lower lid 80 after the heat has been released to the low-pressure side refrigerant and in further cooled and therefore the performance improving state, the container 20 to leave in the direction of a not shown expansion element and the evaporator. The described direction of flow only serves to understand the figures. It is, moreover, determined in an appropriate manner. Down in the longitudinal wall 26 there is a channel 30 and a hole 32 to the low-pressure side refrigerant after flowing through the heat exchanger chamber 22 in the accumulator 21 to supply settled oil. ( 2 ) In the embodiment according to the 3 were two flat filter elements 24 intended. One of them was in front of the canal 30 arranged and the second is located in front of the already mentioned exit 41 in the heat exchanger chamber 22 , With this embodiment, it should be pointed out that the present invention with respect to the placement of such elements provides greater latitude for the designer than the prior art.

The 4 shows the cross section through the container 20 another particularly notable embodiment. In some cases, a larger or specially designed accumulator chamber 21 required, according to 4 was achieved by the flat multi-chamber tube 10 with one to the contour of the container 20 adapted shape and thus extends along a part of the container wall. Again, a longitudinal wall 26 used, which is also adapted to the mentioned contour. On the inside of the container wall there are grooves 27 , in which the longitudinal edges of the longitudinal wall 26 can be inserted. The recording grooves 27 limit the manufacturability of the container 20 by extrusion, not, ie they can be realized by this method. The multi-chamber tube 10 is preferably, but not necessarily, also an extruded tube, for example with two rows of apertures 12 , This training is particularly preferably carried out when, as in the 5 is shown on the corrugated heat exchange ribs 11 is to be omitted as an item by the multi-chamber tube 10 on the outside is equipped with rib-like channels. Here it is also possible, according to a development not shown, the longitudinal wall 26 also in one piece with the multi-chamber tube 10 form, whereby the insertion of a longitudinal wall 26 and on the necessary grooves 27 or the like can be dispensed with. In this case all parts are made of metal, for example aluminum. However, it brings certain advantages already mentioned above for the heat exchange with it when the longitudinal wall 26 made of a material with lower thermal conductivity, such as plastic, and used.

The 6 . 7 and 8th show further embodiments in cross section through an extruded container 20 with two longitudinal walls 26 which then has three chambers or compartments in the container 20 form. These chambers can according to the desired application as a battery chamber 22 or as a heat exchange chamber 21 be educated. In the example according to the 6 became the middle chamber as a heat exchange chamber 22 and the two other chambers as accumulator chambers 21 educated. In the heat exchanger chamber 22 there is a multi-chamber tube 10 which with reference to the above 5 already described. The 7 shows another example in which all three chambers as heat exchange chambers 22 are formed. With the reference number 90 was a design option pointed out, which is the wall thickness of the container 20 partially enlarge the cross section of the chambers - while maintaining the round cross-sectional shape of the container 20 - form so that the insertion of the tube 10 with the heat exchanger rib 11 is relieved. It can be common corrugated ribs 11 can be used, spiraling around the pipe 10 be wrapped. In other cases bie If such a "uniform" cross-section also for the collector chamber 21 at. In the 8th the "uniformed" cross-section was achieved by another means, namely a slight deviation from the round shape of the container, which is still acceptable despite the high pressures in the system.As can be seen from the figure, four were on the circumference of the container 20 distributed gradations 60 provided, which cause the cross section of the upper and lower heat exchanger chamber 22 can be approximately rectangular. The middle chamber was here as Akkumulatorkammer 21 educated.

The device described so far has been as in the following 9 - 12 is shown with the gas cooler 3 united to achieve a particularly compact design of the entire system. The container 20 can in principle be such as it is for example in the 3 shown and already described above.

As is common in prior art two-phase refrigerant air conditioners, the container becomes 20 parallel to a manifold 30 of the condenser, here however of the gas cooler 3 , arranged and connected. The difference is that the prior art is merely a collector, but in this case an accumulator 21 , combined with an internal heat exchanger 22 , at the gas cooler 3 is connected. Specifically, in the embodiment shown, the container 20 by means of two holders 5 at the manifold 4 attached. In the 9 the necessary components of the air conditioning circuit at the inflow and outflow points for the low pressure side LP and the high pressure side HD refrigerant were indicated by appropriate labeling. The gas cooler 3 receives from the compressor coming compressed, high-temperature gaseous HD refrigerant, which is in the gas cooler 3 is cooled by heat exchange with cooling air. The serpentine flow through the gas cooler 3 by groups of parallel flat tubes was indicated by arrows. In the headers 4 of the gas cooler 3 There are partitions that cause the described flow. The HD refrigerant occurs in the embodiment immediately after leaving the gas cooler 3 into the heat exchanger chamber 22 a, as described, in the through the chamber 22 extending multi-chamber tube 10 ,

In the 9 was provided, the passage from the gas cooler 3 to the container 20 by means of a short line 6 from the manifold 4 in the multi-chamber tube 10 make. As an alternative, the shows 12 a slightly more compact training, which is that the line 6 through one of the holders 5 goes through and the multi-chamber tube 10 connected. The ND refrigerant coming from the evaporator is in a state of hypothermia. It passes through the in the accumulator chamber 21 reaching insertion tube 25 in the accumulator chamber 21 and happens while the dryer 24 and a filter 23 at the end of the insertion tube 25 , In contrast to the previously described embodiments, the opening for the oil is in the longitudinal wall 26 directly in the area of the soil. At the upper end of the longitudinal wall 26 is the inflow opening 31 for the gaseous LP refrigerant contained in the heat exchanger chamber 22 through the heat exchanger rib 11 flows to the bottom of the chamber 22 towards the compressor. It is enriched with oil and settled liquid refrigerant, which passes immediately because of the heat absorbed in the heat exchanger in the gaseous state and assumes a lower temperature, whereby the compressor is relieved. The 10 shows, also schematically, a section of a plan view of the device according to 9 ,

The 11 shows a further development idea, which is that the container produced by extrusion 20 no integrated longitudinal wall 26 has, but only with grooves 40 was equipped. These grooves 40 serve to be able to use a plastic existing longitudinal wall, which is otherwise formed as described. Such a design brings advantages in terms of the efficiency of the heat exchange, and it is executable despite the prevailing high pressure, because it is between the heat exchanger chamber 22 and the accumulator chamber 21 There are no significant pressure differences.

In the 9 and 10 an additional longitudinal wall made of plastic was directly attached to the metal longitudinal wall 26 as indicated by the two parallel lines.

The container 20 The proposed device is also characterized by its slim design. The ratio of its length L to its diameter D is at least 3: 1, preferably the ratio is about 6: 1.

Claims (26)

Apparatus for treating the refrigerant circulating in a transcritical air conditioning circuit comprising: compressor ( 1 ), Gas cooler ( 3 ), Evaporator, (heat exchanger) and expansion element and thereby passes through a high-pressure side and low-pressure side, in which the refrigerant has different temperature, wherein the device is a flat multi-chamber tube ( 10 ), through which the one side flows and which in a container ( 20 ), through which the other side flows to to serve as an intermediate heat exchanger, wherein in the container ( 20 ) an accumulator chamber ( 21 ) and a heat exchanger chamber ( 22 ), characterized in that the multi-chamber tube ( 10 ) containing containers ( 20 ) with a collecting pipe ( 4 ) of a heat exchanger ( 3 ), wherein the accumulator chamber ( 21 ) and the heat exchanger chamber ( 22 ) parallel and over at least a substantial portion of the length of the slender container ( 20 ). Apparatus according to claim 1, characterized in that an insertion tube ( 25 ) for the low-pressure side in the accumulator chamber ( 21 ) is arranged. Apparatus according to claim 1 and 2, characterized in that a dryer ( 24 ) in or on the introduction tube ( 25 ) is arranged. Device according to one of the preceding claims, characterized in that in the container ( 20 ) at least one longitudinal wall ( 26 ) is arranged, at whose one end at least one inflow opening ( 31 ) is present to the low pressure side from the accumulator chamber ( 21 ) in the heat exchanger chamber ( 22 ) of the container ( 20 ) bring to. Device according to one of the preceding claims, characterized in that at the other end of the longitudinal wall ( 26 ) at least one opening ( 32 ) is present for refrigerant contained in the refrigerant. Apparatus according to claim 4 or 5, characterized in that the longitudinal wall ( 26 ) preferably outside the median plane of the container ( 20 ) is arranged so that the accumulator chamber ( 21 ) is larger than the heat exchanger chamber ( 22 ). Device according to one of the preceding claims, characterized in that the inside of the container ( 20 ) located heat exchanger chamber ( 22 ) extends to a partial radius thereof. Device according to one of the preceding claims, characterized in that the container ( 20 ) and the flat multi-chamber tube ( 10 ) are produced by extrusion. Apparatus according to claim 8, characterized in that the multi-chamber tube substantially undeformed by the heat exchanger chamber ( 22 ) of the container ( 20 ) and at least the major part of the tube length with heat-conducting ribs ( 11 ), as far as possible the entire remaining cross section of the heat exchange chamber ( 22 ) fill out. Device according to one of the preceding claims, characterized in that the container ( 20 ) with or without longitudinal wall ( 26 ) is a tube produced by extrusion, the ends of which are provided with a cover ( 80 ) are closed. Device according to one of the preceding claims, characterized in that an insulating plate or the like, adjacent to the longitudinal wall ( 26 ) is arranged. Device according to one of the preceding claims 1-10, characterized characterized in that instead of the longitudinal wall an insulation plate can be used in the pipe. Apparatus according to claim 12, characterized in that on opposite sides of the pipe wall grooves or the like receptacles ( 27 ) are formed, in which the insulation plate can be used. Device according to one of the preceding claims, characterized in that the container ( 20 ) is shielded from the flow of cooling air through the heat exchanger, preferably through the gas cooler. Device according to one of the preceding claims, characterized in that the collecting pipe ( 4 ) of the heat exchanger, preferably the gas cooler, and the container ( 20 ) are arranged at a small distance from each other and form a structural unit. Device according to one of the preceding claims, characterized in that the container ( 20 ) is arranged in the air flow direction behind an air guide plate. Device according to one of claims 1-15, characterized in that the container ( 20 ) on its outside at least partially with an insulation ( 50 ) is provided. Device according to one of the preceding claims, characterized in that in the container ( 20 ) one or more filters ( 23 ) are provided for the treatment of the refrigerant. A device for treating the refrigerant circulating in a transcritical air-conditioning circuit, comprising: compressor, gas cooler, evaporator, (heat exchanger) and expansion element, passing through a high-pressure side and low-pressure side, in which the refrigerant has different temperature, the device being a flat multi-chambered tube ( 10 ), through which the one side flows and which in a container ( 20 ), through which the other side flows to than To serve intermediate heat exchanger, wherein in the container ( 20 ) an accumulator chamber ( 21 ) and a heat exchanger chamber ( 22 ), characterized in that the container ( 20 ) as a slender hollow body with at least one longitudinal wall ( 26 ) or with brackets ( 27 ) is formed for holding at least one inserted longitudinal wall, wherein the at least one longitudinal wall ( 26 ) at least one opening ( 31 ), so that the refrigerant the chambers ( 21 . 22 ) and wherein the accumulator chamber ( 21 ) and the heat exchanger chamber ( 22 ) parallel and over at least a substantial portion of the length of the slender container ( 20 ). Apparatus according to claim 19, characterized in that the flat multi-chamber tube ( 10 ) longitudinally through the heat exchanger chamber ( 22 ) and with heat-conducting ribs ( 11 ) is busy. Device according to claim 19 or 20, characterized that the inserted longitudinal wall a lower heat transfer value has, for example, consists of plastic. Device according to claims 1-21, characterized in that the heat-conducting rib ( 11 ) the remaining cross section of the heat exchanger chamber ( 22 ) at least as far as possible. Device according to one of claims 18-22, characterized in that the longitudinal wall ( 26 ) is arranged outside the center plane of the container. Device according to one of the preceding claims, characterized in that the multi-chamber tube ( 10 ) including the heat-conducting ribs ( 11 ) can be produced as extruded product. Device according to one of claims 19-24, characterized in that a dryer ( 24 ) in the accumulator chamber ( 21 ) and preferably also a filter ( 23 ) in the container ( 20 ) are arranged. Device according to one of the preceding claims, characterized in that the ratio of the length (L) to the diameter (D) of the container ( 20 ) ≥ 3: 1.