Air conditioning system for a motor vehicle with a hot air duct section to a refrigerant storage unit and motor vehicle with such an air conditioning system

Abstract

An air conditioning system (10) for a motor vehicle (100) is described, comprising a refrigeration system (12) which has at least one heat exchanger (14, 16, 18) supplied with ambient air and / or recirculated air, such that conditioned air (KL) is provided downstream of the heat exchanger (14, 16, 18) with respect to a main airflow direction (HLR), wherein the refrigeration system (12) has a refrigerant storage tank (20) arranged, in particular on the low-pressure side, and wherein the air conditioning system (10) has at least one ventilation duct section (22) downstream of the heat exchanger (14, 16, 18) with respect to the main airflow direction (HLR), which is connected to at least one outlet opening (22a) in an interior space (102) of the motor vehicle (100).It is provided that the air conditioning system (10) has at least one heated air duct section (24) downstream of the heat exchanger (14, 16, 18) with respect to the main airflow direction (HLR), which is configured to supply conditioned air (KL) to the refrigerant storage tank (20) as needed. Furthermore, a motor vehicle (100) with such an air conditioning system (10) is described.

Description

DESCRIPTION:

[0001] The invention relates to an air conditioning system according to the preamble of claim 1 for a motor vehicle with a refrigeration system which has at least one heat exchanger which is acted upon by ambient air and / or circulating air in such a way that conditioned air is provided downstream of the heat exchanger with respect to a main air flow direction, wherein the refrigeration system has a refrigerant accumulator arranged in particular on the low-pressure side, wherein the air conditioning system has at least one ventilation duct section downstream of the heat exchanger with respect to the main air flow direction, which is connected to at least one outlet opening in an interior of the motor vehicle.

[0002] Such an air conditioning system is known, for example, from JP 2013-208 939 A. For the state of the art for the relevant refrigeration systems, reference is also made to DE 10 2022 115 608 A1, DE 10 2007 036 299 A1 and DE 39 14 252 A1.

[0003] Furthermore, it is known from the prior art to provide an electric heating device on a refrigerant storage tank, particularly on the low-pressure side of a refrigeration system, in order to heat the refrigerant as needed during operation of the refrigeration system. Reference is made to DE 10 2018 205 432 A1, DE 10 2017 208 227 A1, and DE 10 2017 208 225 A1 as examples. EP 2 075 873 A1 and DE 10 2022 205 666 A1 are also worth mentioning.

[0004] Heating the refrigerant can be particularly advantageous during service work on the refrigeration system, as it supports the essentially complete removal of the refrigerant from the refrigeration system (emptying the refrigeration system). Furthermore, heating the refrigerant can also be advantageous in a refrigeration system that has a heat pump function.

[0005] The object underlying the invention is to provide a refrigerant storage device that can be heated in an energy-efficient manner, in particular using heat sources already present in a motor vehicle.

[0006] This problem is solved by an air conditioning system and a motor vehicle having the features of the respective independent patent claim. Advantageous embodiments with useful further developments are specified in the dependent patent claims.

[0007] What is proposed is an air conditioning system for a motor vehicle, comprising a refrigeration system having at least one heat exchanger supplied with ambient air and / or recirculated air, such that conditioned air is provided downstream of the heat exchanger with respect to a main air flow direction. The refrigeration system has a refrigerant reservoir, arranged in particular on the low-pressure side. The air conditioning system has, downstream of the heat exchanger with respect to the main air flow direction, at least one ventilation duct section which is connected to at least one outlet opening in an interior of the motor vehicle. It is provided that, downstream of the heat exchanger with respect to the main air flow direction, the air conditioning system has, downstream of the heat exchanger with respect to the main air flow direction, at least one heating air duct section which is configured to convey conditioned air to the refrigerant reservoir as required.

[0008] This makes it possible to heat refrigerant contained in the refrigerant storage unit due to heat transfer from the conditioned air to the refrigerant storage unit, in particular its housing, and the refrigerant stored therein.

[0009] In the air conditioning system, the hot air duct section has an air damper arranged downstream of the heat exchanger, which is configured to enable or disable the conveyance of conditioned air toward the refrigerant reservoir. This allows the conveyance of conditioned air to the refrigerant reservoir to be adjusted as needed. In particular, such an air damper can be connected to a control unit of the air conditioning system, which is configured to adjust an opening position of the air damper.

[0010] In the air conditioning system, the hot air duct section has a fan device configured to adjust the air volume flow delivered to the refrigerant storage unit. In addition to the free air flow, the air volume flow can be used to ensure a forced air flow to the refrigerant storage unit and adjust it as needed.

[0011] Such a fan device can be arranged, in particular, downstream of the air damper. A reversed arrangement of the fan device and air damper is also conceivable. Furthermore, such a fan device is connected to the control unit of the air conditioning system, whereby the fan device can be operated, in particular switched on / off, depending on the opening position of the air damper.

[0012] In the air conditioning system, the hot air duct section can have an outflow section facing the refrigerant reservoir, such that conditioned air impinges on the refrigerant reservoir. Such an outflow section can also be referred to as an outflow nozzle. In particular, the outflow section can be designed so that the conditioned air impinges on the largest possible area of ​​the refrigerant reservoir housing in order to efficiently control the temperature of the refrigerant reservoir.

[0013] In the air conditioning system, the heating air duct section can be connected to a heating line section running along a housing of the refrigerant storage unit and / or through the housing, through which the conditioned air flows.

[0014] The heating line section can be connected to a return air duct section configured to reintroduce conditioned air after it has flowed through the heating line section upstream of the heat exchanger relative to the main air flow direction, such that the conditioned air reaching the refrigerant storage unit is (re)circulated. Such a configuration with a return air duct section represents a kind of expansion stage of the air conditioning system, whereby targeted (re)circulation can be implemented in addition to the free outflow of the air flow acting on the refrigerant storage unit.

[0015] Due to (re)circulation of the conditioned air, a desired temperature level in the area of ​​the refrigerant storage can be efficiently achieved and adjusted.

[0016] In the air conditioning system, an additional electric heating element can be arranged in the hot air duct section, particularly downstream of the fan device. This makes it possible to additionally heat the air already conditioned by the heat exchanger. The additional heating element can be connected to the control unit of the air conditioning system, so that it can be switched on / off, particularly depending on the opening position of the air flap and / or the operating state of the fan device.

[0017] Optional temperature sensors can monitor the condition of the airflow entering the refrigerant storage tank and provide feedback to the control unit. Additional temperature sensors in the optional return air duct section enable (at least approximately) balancing of the heat loss in the airflow and thus the heating capacity in the refrigerant storage tank in combination with an air volume flow derived via the fan characteristic curve, taking into account the air density and air mass flow.

[0018] In the air conditioning system, the refrigeration system may further comprise: a refrigerant compressor; a first heat exchanger, in particular a gas cooler or condenser; a second heat exchanger, in particular an evaporator; a third heat exchanger, in particular a heating register; wherein the second heat exchanger and the third heat exchanger are arranged one after the other with respect to the main air flow direction.

[0019] The refrigeration system can comprise a fourth heat exchanger, in particular a chiller, which is arranged parallel to the second heat exchanger with respect to the refrigerant flow direction and which is connected to a coolant circuit in such a way that heat transfer is possible between the coolant and the refrigerant.

[0020] A motor vehicle may be equipped with an air conditioning system as described above.

[0021] Further advantages and details of the invention will become apparent from the following description of embodiments with reference to the figures. Fig. 1 a simplified and schematic representation of an air conditioning system for a motor vehicle with a heating air duct section; Fig. 2 a simplified and schematic representation of a refrigerant storage tank with a heating air duct section; Fig. 3 a simplified and schematic representation of an air conditioning system for a motor vehicle with a heating air duct section and a return air duct section; Fig. 4 a simplified and schematic representation of a refrigerant storage tank with heating air duct section and return air duct section; Fig. 5 a simplified and schematic representation of a conditioning ring channel with a refrigerant storage.

[0022] In Fig. 1 shows a simplified and schematic representation of an air conditioning system 10 of a motor vehicle 100.

[0023] The air conditioning system 10 comprises a refrigeration system 12 having at least one heat exchanger 14, 16, 18, which is supplied with ambient air UL and / or recirculated air, such that, relative to a main air flow direction HLR, conditioned air KL is provided downstream of the heat exchanger 14, 16, 18. The refrigeration system 12 further comprises a refrigerant reservoir 20, arranged in particular on the low-pressure side.

[0024] It is pointed out that in the Fig. 1 the refrigeration system 12 is mentioned with some components, but no known refrigerant circuit of the refrigeration system 12 is shown.

[0025] In the example of Fig. 1, an evaporator 14, a heating register 16 and an electric heating element 18 are shown as heat exchangers for conditioning air. However, it should be noted that this is a purely exemplary configuration that does not necessarily have to be present in a refrigeration system 12. In particular, the heating register 16 or the electric heating element 18 can be understood as optional, so that only one of these two components is present in a refrigeration system 12. Furthermore, it would also be conceivable to integrate, for example, a heating heat exchanger through which fluid, i.e. a water-glycol mixture, flows instead of a heating register 16, or to provide both heat exchanger designs together.

[0026] The air conditioning system 10 has, with respect to the main air flow direction HLR, downstream of the (at least one) heat exchanger 14, 16, 18, at least one ventilation duct section 22 which is connected to at least one outlet opening 22a in an interior 102 of the motor vehicle 100.

[0027] The air conditioning system 10 has, with respect to the main air flow direction HLR, at least one heating air duct section 24 downstream of the (at least one) heat exchanger 14, 16, 18, which is configured to convey conditioned air to the refrigerant storage unit 20 as required.

[0028] In this example, the heating air duct section 24 has an air flap 26 arranged downstream of the (at least one) heat exchanger 14, 16, 18, which is designed to enable or prevent the conveyance of conditioned air KL in the direction of the refrigerant storage unit 20.

[0029] In addition to the free flow of a refrigerant reservoir 20 via the heating air duct section 24, the heating air duct section 24 can have a blower device 28 which is designed to specifically adjust an air volume flow conveyed to the refrigerant reservoir 20 in order to thereby realize a forced flow.

[0030] The hot air duct section 24 can have an additional heating element 29 to further heat the air flowing to the refrigerant reservoir 20 as needed. An optionally provided, but not shown, temperature measurement sensor system can be used to monitor the amount of heat introduced and the resulting achievable or resulting inflow temperature of a refrigerant reservoir 20, or can be arranged in the area of ​​the hot air duct section 24.

[0031] Furthermore, the heating air duct section 24 in this example has an outflow section 30 facing the refrigerant storage 20, such that conditioned air KL hits the refrigerant storage 20. As can be seen from the Fig. 1, the outflow section 30 can be designed such that the conditioned air KL hits the refrigerant storage 20 over as large an area as possible, which is illustrated by the three parallel contour arrows.

[0032] In this example, the conditioned air KL supplied to the refrigerant reservoir 20 escapes into the environment of the air conditioning system 10, in particular into an engine compartment of the motor vehicle 100 (not shown here).

[0033] Fig. 2 shows in a simplified and schematic representation the refrigerant storage 20 of the Fig. 1 with the outlet section 30 of the heating air duct section 24.

[0034] From the presentation of the Fig. 2 it can be seen that the usually cylindrically shaped refrigerant reservoir 20 can be at least partially surrounded by conditioned air KL on its outer side 20a. In the example of Fig. 2, the conditioned air KL hits the refrigerant storage tank from the left (upstream side). The conditioned air KL then flows at least partially along the refrigerant storage tank before escaping to the right side into the environment.

[0035] Please note that the outlet section 30 shown here is purely exemplary. It may, in particular, have a different shape or at least partially encompass the refrigerant reservoir, allowing the conditioned air to be distributed more precisely.

[0036] Fig. 3 shows essentially the same air conditioning system 10 as in the Fig. 1. Accordingly, a renewed description of the above-mentioned Fig. 1 mentioned components and reference is made to the above description.

[0037] In the air conditioning system 10 of the Fig. 3, the heating air duct section 24 is connected to a heating line section 32 running along the housing of the refrigerant storage unit 20, through which the conditioned air flows. For example, the heating line section 32 can be hollow-cylindrical, so that the conditioned air flows along the entire circumference of the refrigerant storage unit 20.

[0038] Furthermore, in the example of Fig. 3 the heating line section 32 is connected to a return air duct section 34 which is designed to reintroduce conditioned air after flowing through the heating line section 32 upstream of the heat exchanger 14, 16, 18 with respect to the main air flow direction HLR, such that conditioned air KL reaching the refrigerant storage 20 is (re-)circulated.

[0039] In the example of Fig. 3, the heating line section 32 is arranged outside the housing of the refrigerant storage unit 20. However, it is also conceivable that the heating line section 32 is guided through an interior space of the refrigerant storage unit 20 delimited by the housing.

[0040] Fig. Figure 5 shows a simplified and schematic view of an alternative concept for supplying the refrigerant storage 20 with conditioned air. The concept according to Fig. 5 is based on the idea of ​​(re-)circulation of conditioned air according to the example of Fig. 3 and Fig. 4 on.

[0041] In the Fig. In the concept illustrated in Figure 5, the refrigerant reservoir 20 is arranged or integrated in an independent or separate conditioning ring duct 36. A blower device 28 and a heating element 29 are arranged in the conditioning ring duct 36. This allows the refrigerant reservoir 20 to be supplied with an air flow or conditioned air KL that can be adjusted by the blower device 28 and tempered by the heating element 29. The air flow is continuously (re)circulated in the conditioning ring duct 36. The part of the conditioning ring duct 36 downstream from the heating element 29 to the refrigerant reservoir 20 can be understood as the heating line section 32, and the part of the conditioning ring duct 36 downstream from the refrigerant reservoir 20 to the blower device 28 can be understood as the return air duct section 34.

[0042] The above-mentioned with reference to the Fig. The (temperature) measurement sensors described in 1 to 4, which can be provided as optional accessories, can be used to monitor and balance the air flow in the heating line section 32 and in the return air duct section 34. The corresponding measured values ​​or data are processed via a control unit that is not further described or sketched.

[0043] The use of the described conditioning concept according to the examples of Fig. 1 to 5 of a refrigerant storage unit 20 can be used both during operation of a motor vehicle 100, in particular when the refrigeration system 12 is operated in heat pump mode, and for servicing purposes for the accelerated and optimized emptying of a refrigeration system 12. In the latter case, a special service mode should preferably be activated by the workshop in order to be able to specifically implement the conditioning of the air flow acting on the refrigerant storage unit 20 even in such an application.

[0044] With regard to possible embodiments of a refrigerant storage device with a heating device, reference is also made to the German patent application filed by the applicant at the same time with the title "Refrigerant storage device with heating line section through which heating fluid flows, thermal management system with such a refrigerant storage device and motor vehicle with such a thermal management system", in which conditioned air from a ventilation system is also listed as a possible heating fluid.

[0045] Finally, with regard to heating refrigerant during service work using a suction device and with regard to a corresponding method, reference is made to the German patent application filed concurrently by the applicant entitled "Method for emptying a refrigeration system of a motor vehicle and refrigeration system for carrying out the method." For example, a refrigerant storage device 20 as described above can be used in the method and refrigeration system described therein.

Claims

[1] Air conditioning system (10) for a motor vehicle (100) with a refrigeration system (12) which has at least one heat exchanger (14, 16, 18) which is supplied with ambient air and / or recirculated air, such that conditioned air (KL) is provided downstream of the heat exchanger (14, 16, 18) with respect to a main air flow direction (HLR), wherein the refrigeration system (12) has a refrigerant accumulator (20) arranged in particular on the low-pressure side, wherein the air conditioning system (10) has at least one ventilation duct section (22) downstream of the heat exchanger (14, 16, 18) with respect to the main air flow direction (HLR), which is connected to at least one outlet opening (22a) in an interior (102) of the motor vehicle (100), wherein the air conditioning system (10) has, downstream of the heat exchanger (14, 16, 18) with respect to the main air flow direction (HLR), at least one heating air duct section (24) which has an air flap (26) arranged downstream of the heat exchanger (14, 16, 18), characterized by that the heating air duct section (24) is designed to convey conditioned air (KL) to the refrigerant storage (20) as required, and the air flap (26) is designed to enable or prevent the conveyance of conditioned air (KL) in the direction of the refrigerant storage (20), wherein the heating air duct section (24) has a fan device (28) which is designed to adjust an air volume flow conveyed to the refrigerant reservoir (20), and wherein the blower device (28) is connected to a control unit of the air conditioning system (10) and is operable depending on an opening position of the air flap (26). [2] Air conditioning system (10) according to claim 1, characterized by that the heating air duct section (24) has an outflow section (30) facing the refrigerant accumulator (20) such that conditioned air (KL) hits the refrigerant accumulator (20). [3] Air conditioning system (10) according to claim 1 or 2, characterized by that the heating air duct section (24) is connected to a heating line section (32) running along a housing of the refrigerant accumulator (20) and / or through the housing, through which the conditioned air (KL) flows. [4] Air conditioning system (10) according to claim 3, characterized byin that the heating line section (32) is connected to a return air duct section (34) which is designed to reintroduce conditioned air (KL) after flowing through the heating line section (32) upstream of the heat exchanger (14, 16, 18) with respect to the main air flow direction (HLR), such that conditioned air reaching the refrigerant reservoir (20) is (re-)circulated. [5] Air conditioning system (10) according to one of the preceding claims, characterized by that an additional electric heating element (29) is arranged in the heating air duct section (24), in particular downstream of the blower device (28). [6] Air conditioning system (10) according to one of the preceding claims, characterized by that the refrigeration system has: a refrigerant compressor; a first heat exchanger, in particular a gas cooler or condenser; a second heat exchanger (14), in particular an evaporator; a third heat exchanger (16), in particular a heating register; wherein the second heat exchanger (14) and the third heat exchanger (16) are arranged one after the other with respect to the main air flow direction (HLR). [7] Air conditioning system (10) according to claim 6, characterized by in that the refrigeration system (12) has a fourth heat exchanger, in particular a chiller, which is arranged parallel to the second heat exchanger (14) with respect to the refrigerant flow direction and which is connected to a coolant circuit in such a way that heat transfer is possible between the coolant and the refrigerant. [8] Motor vehicle (100) with an air conditioning system (10) according to one of the preceding claims.

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