EP3314178A1

EP3314178A1 - Device and method for deicing a heat exchanger in evaporator operation of a cooling system and vehicle having such a device

Info

Publication number: EP3314178A1
Application number: EP16753579.8A
Authority: EP
Inventors: Otfried Schwarzkopf
Original assignee: Voss Automotive GmbH
Current assignee: Voss Automotive GmbH
Priority date: 2015-06-26
Filing date: 2016-06-27
Publication date: 2018-05-02
Also published as: WO2016206816A1; DE102015008325A1

Abstract

In order to deice a heat exchanger in evaporator operation of a cooling system (1), which heat exchanger was iced at low evaporation temperatures, wherein refrigerant (30) can flow or flows through the heat exchanger in evaporator operation (20), a device for deicing such a heat exchanger in evaporator operation (20) is a heat exchanger device (12, 55) which is situated in a second coolant circuit or a separate, connectable and disconnectable path of the at least one first coolant circuit (65) and can be provided or is provided in heat exchange with the heat exchanger in evaporator operation (20). In a vehicle (100), in particular a land vehicle, having at least one electric drive (50) and/or at least one traction battery (59) and having at least one cooling system (1) which can be or is operated in heat pump mode and which has at least one heat exchanger in evaporator operation (20) which, as part of a refrigerant circuit (66), can have or has refrigerant (30) flowing through it, and having at least one first coolant circuit (65), at least one heat exchanger device (12, 55), which is provided in a second coolant circuit or a separate, connectable and disconnectable path of the at least one first coolant circuit (65), is placed in heat-conducting contact with the heat exchanger in evaporator operation (20) for deicing the heat exchanger in evaporator operation.

Description

Device and method for defrosting a heat exchanger in the

Evaporator operation of a refrigeration system and vehicle with such

Facility

The invention relates to a device and a method for deicing a heat exchanger in the evaporator operation of a refrigeration system, when receiving heat from the environment or ambient air, wherein the heat exchanger in the evaporator operation as part of a refrigerant circuit for receiving heat from the environment with refrigerant flowed through or flowed through or is, the refrigeration system in the heat pump mode is operated or operated and wherein at least a first coolant circuit of a vehicle is provided, and a vehicle, in particular land vehicle, with at least one electric drive and / or at least one traction battery and at least one refrigeration system with at least one heat exchanger in evaporator operation.

Vehicles, such as land vehicles, with air conditioning or refrigeration systems with

Air conditioners are known in the art. Such a Klimaanlange consists at least of the following components: a compressor, a condenser or gas cooler, depending on whether a refrigerant dependent one

Condensation takes place or not, as well as an expansion element and an evaporator. If no condensation takes place, but a cooling of a supercritical gas as refrigerant, which was previously brought into the supercritical state, is spoken by a gas cooler. If a condensation occurs in the wet steam area when using another refrigerant, for example HFO1, 2,3,4yf can be used as the refrigerant, this is referred to as a condenser. In a gas cooler, for example, CO ₂ can be used as the refrigerant. In the closed system, a cycle takes place. The refrigerant is low in pressure

gaseous state sucked by the compressor and compressed to a higher pressure. The refrigerant then flows through the condenser or gas cooler, depending on which refrigerant is used, and condenses under heat release. The refrigerant is then expanded to a low pressure and subsequently receives heat via the evaporator. This process starts again from the beginning.

CONFIRMATION COPY Also known are heat pumps that require a comparable system technology as for an air conditioner. In an air conditioning system, the benefit is to extract heat from a room via the evaporator, removing the heat from the room by absorbing heat from the system by evaporating a refrigerant and then passing it through the condenser or

Gas cooler is discharged to the environment again. With a heat pump, the benefit lies on the condenser or gas cooler side. Here, heat from the environment is taken up by the evaporator and a space, e.g. the vehicle cabin, fed by the gas cooler or condenser.

Refrigeration systems that can perform both functions are also known for use in vehicles, which can thus cool and heat. These

Refrigeration systems are designed to allow cooling in summer and heating in winter. In the Air Conditioning (AC) mode or in summer mode, a heat exchanger is driven here as a condenser or gas cooler to dissipate the heat. In winter operation, the same heat exchanger is run as an evaporator to absorb heat. To enable this even at low outdoor temperatures, the evaporation temperatures are correspondingly low. Accordingly, the surface temperature of the

Heat exchanger in evaporator operation below the freezing point of water. Since the humidity on the cold evaporator is reflected as ice, over time creates an ice sheet, which reduces the efficiency of the refrigeration system, as it leads to thermal insulation, which is also known as a negative effect in, for example, refrigerators. As already mentioned in the article "Energy Efficient

Deicing with passenger car heat pump systems ", ATZ 02/2015, 117. Jg., P. 40-43, noted, decreases due to the low thermal conductivity of the forming ice layer in comparison to the material of the heat exchanger in the

Evaporator operation of heat transfer. Usually, the heat exchanger is traversed by air. Due to ice formation, however, the air path through the heat exchanger is blocked, making it even higher

Pressure loss and to reduce the existing surface for heat transfer comes. For efficient operation of the refrigeration system, it is therefore necessary to remove the ice sheet from time to time by defrosting. An acquaintance Possibility here is to drive a reverse mode heat pump operation- refrigeration system operation, in which the "cold side" of the

This causes the evaporator to thaw out or come to a standstill However, driving the refrigeration system in reverse mode to defrost or defrost the evaporator is disadvantageous. Mode) heat can not be generated in cooling mode, although there is a need for this in winter, for example: vehicles with an AC and an HP mode are, for example, the Renault Zoe and the BMW i3 For example, an electric heater must be provided or activated, but this is not an advantage since energy for generating heat must be additionally generated during the reverse operation, which is disadvantageous in hybrid and electric vehicles the additional energy requirement of the electric heater significantly reduces the range of the vehicle.

From DE 10 2009 009 538 A1, for example, such

Heat pump mode in which the air conditioner is designed so that it can be operated either in a cooling mode and in a heating mode known. From DE 10 2013 008 801 A1 it is also known, a

Provide refrigerant circuit, wherein condenser or gas cooler of the

Refrigerant circuit are arranged to generate convection for heat dissipation on the vehicle front. To avoid heat losses in heat pump mode, short lines are used and the individual

Components arranged in close proximity to each other.

A condenser is often provided with a condenser fan for supplying air. In the condenser or gas cooler, the gaseous, superheated refrigerant is cooled to a lower temperature and liquefied. Since heat is drawn from the refrigerant during liquefaction, the condenser must deliver this heat to a surrounding cooling medium, such as air or water. The condenser fan has the task in all

Operating conditions of the vehicle for adequate ventilation of the vehicle

To provide capacitor. By a sufficient ventilation of the condenser while the refrigerant pressure is kept low on the high pressure side. Here, it is also known to turn on and off the condenser fan depending on the refrigerant pressure by a pressure switch. This is often a, cooling coil condenser used in which a passage of air is particularly well possible.

However, if the heat exchanger in the form of the coil condenser is driven as an evaporator to absorb heat, e.g. During winter operation, the ice layer on the outside of the heat exchanger, which forms at low temperatures, may obstruct the passage of air or even make it completely impossible.

From DE 11 2012 005 079 T5 a heat pump cycle is known which comprises a refrigerant circuit and a coolant circuit. A first heat exchanger and a second heat exchanger are between the

Refrigerant circuit and the coolant circuit arranged. The first

The heat exchanger includes an outer heat exchanger that functions as an evaporator in a heating operation, and a radiator for radiating heat from a coolant. The second heat exchanger transfers heat from a refrigerant under a high pressure to the refrigerant in the heating operation. The temperature of the refrigerant within the second heat exchanger is higher than the temperature of the refrigerant within the first heat exchanger. Heat, which is obtained from the second heat exchanger is from the first

Heat exchanger supplied by the coolant. Heat obtained from the second heat exchanger is stored in the coolant. In one

Defrosting operation, the coolant that has stored heat is delivered to the first heat exchanger. It is thus a heat exchanger system

provided in which a radiator of the cooling water system with a

Condenser of a refrigeration system is coupled, wherein both components in the vehicle behind the radiator grille arranged in series one behind the other and in a

common component are provided so that they inevitably come in a thermally conductive contact. According to EP 1 108 575 A1, a similar arrangement of an air conditioning system for vehicles is disclosed. From DE 196 44 488 A1 a method for defrosting a cooler or heat exchanger in a refrigeration system is known, wherein the cooler is flowed through by a coolant. The radiator is shut off from the coolant circuit and only the coolant contained in the radiator is heated, allowing it to circulate through the radiator via a bypass line, so that as little as possible energy is required for the defrosting process. It is provided a bypass line surrounding the radiator, in which a pump and a

Heating device are arranged. Warmsole flows through as a heat transfer medium the closed circuit of the heating register. Again, a fluid is thus used to defrost an evaporator. Similar solutions can also be found in US Pat. No. 6,318,107 B1, EP 2 119 986 A1, EP 2 940 409 A1 and DE 29 46 466 A1.

It turns out to be problematic, as already mentioned, to remove a once built up ice layer on such a heat exchanger in the evaporator operation again. Therefore, it would be desirable to provide measures by which this without great and expensive effort and without the need for driving the refrigeration system or its heat exchanger in the reverse mode or at least only briefly driving the refrigeration system or of their

Heat exchanger in reverse mode is enabled.

The present invention is therefore an object of the invention to provide a device or a method for deicing a heat exchanger in the evaporator operation of a refrigeration system, in particular a vehicle, wherein the

Heat exchanger in the evaporator operation is flowed through or flowed through with refrigerant, which allows an energy-efficient defrosting, without the

Necessity for reverse operation of the heat exchanger or for only lesser cycle length and / or intensity of reverse mode

Heat exchanger.

The object is achieved for a device according to the preamble of claim 1, characterized in that the device is a heat exchanger device arranged in a second coolant circuit or a separate, connectable and disconnectable path of the at least one first coolant circuit and in Heat exchange with the heat exchanger in the evaporator operation is providable or provided. For a method for deicing a heat exchanger in

Evaporator operation of a refrigeration system according to the preamble of claim 8, the object is achieved in that removed by a heat exchanger means heat a refrigerant circuit and the heat exchanger in

Evaporator operation is supplied. For a vehicle according to the preamble of claim 11, the object is achieved in that at least one

Heat exchanger device, as mentioned above, in a second

Coolant circuit or a separate, switched on and off path of the at least one first coolant circuit is arranged, is provided in the heat exchanger to the heat exchanger in the evaporator operation. Further developments of the invention are defined in the dependent claims.

As a result, a device for defrosting a heat exchanger, which is operated in the so-called heat pump mode (for heat generation) in evaporator operation, is provided as components of a system or refrigeration system or an arrangement or a system in a vehicle. Such a vehicle refrigeration system can be operated both in an air conditioning mode and in a heat pump mode. In each of the modes, the vehicle refrigeration system includes one

Evaporator operation, wherein evaporator in the refrigeration mode is an evaporator of the refrigeration system and in the heat generation mode of the heat exchanger, which is operated as an evaporator in the latter mode of operation of the heat exchanger, this tends to icing. In the air conditioning mode, however, the heat exchanger is operated as a condenser or gas cooler, in which he is to dissipate heat and therefore usually does not tend to icing.

The device for defrosting the heat exchange is as

Formed by heat exchange or heat-conducting contact with the heat exchanger in the evaporator operation or flowing through the heat exchanger in the evaporator operation or flowable refrigerant defrosting of the ice layer on the heat exchanger in

Evaporator operation. As a heat exchanger in the evaporator operation here any heat exchanger of a refrigeration system is referred to, as a heat exchanger in the heat Pump mode operates in the evaporator mode, wherein the refrigerant flowing through it absorbs heat and evaporates, using ambient air as the heat source, and accordingly at low

Evaporation temperatures tends to icing. The heat exchanger device serves as an additional device for defrosting ice layers on the

Heat exchanger in evaporator operation. In particular, the

Heat exchanger device to a coolant circuit of a vehicle, such as in particular an electric vehicle, which is equipped with the refrigeration system or system that includes the heat exchanger in the evaporator operation, heat and supplies them to the enteisenden heat exchanger in the evaporator operation.

Due to the provision of a heat exchange or in particular

thermally conductive contact with the heat exchanger in the evaporator operation, a heat transfer from the heat exchanger means to the

Heat exchanger in the evaporator operation done. Under a heat exchange, any exchange of heat with the heat exchanger in the

Evaporator operation, under a thermally conductive contact with the heat exchanger in the evaporator operation is always the heat-conducting contact with any part of the heat exchanger in the evaporator operation, ie in particular a possibly provided housing and / or a frame and / or at least one Durchströmungsweg the heat exchanger in the evaporator operation by the Refrigerant can flow or flows, understood. The heat exchanger device is provided as an independent component in addition to a cooler and an evaporator or the heat exchanger in the evaporator operation. The

Heat exchanger device is arranged in a separate, second coolant circuit or in a separate, connectable and disconnectable path of the at least one first coolant circuit, which in particular comprises the radiator. When providing a separate second coolant circuit comprising the heat exchanger device, there are thus at least two coolant circuits.

intended. When providing the separate path of the first coolant circuit comprising the heat exchanger device, it can advantageously be switched on and off by means of at least one switching valve.

The heat exchanger in evaporator operation is defrosted on the outside. This means that preferably the heat is a frame and / or housing of the Heat exchanger in the evaporator mode and / or the ice layer or the outside built on the heat exchanger in the evaporator operation

Ice sheet is supplied. Optionally, a heat transfer from the refrigerant also take place. Advantageously, however, the heat supply to the refrigerant should not lead to a reduction in the supply of heat to be defrosted ice sheet on the heat exchanger in the evaporator operation. It can therefore also be provided for the Abtaubetrieb, ie during the defrosting process, to prevent flow through the heat exchanger in the evaporator operation, so no refrigerant through the heat exchanger in

Evaporator operation or evaporator to flow to supply the heat only the ice layer on the heat exchanger in the evaporator mode or evaporator to defrost this. By a temporary

Preventing the flow through the heat exchanger or evaporator with refrigerant, the defrost cycle can be shortened.

However, if the heat exchanger in the evaporator operation or evaporator continues to flow through the refrigerant, then advantageously there is also a heat absorption via this, wherein only a short-term heat supply will take place over it. The system can be a refrigeration system, which in the

Air conditioning and heat pump mode can be operated or a pure heat pump system, due to the provision of

Heat exchanger device can thus heat in the heat exchanger in

Be evaporated evaporator operation to defrost this and thus to remove an ice layer of this. Accordingly, at least the cycle duration and / or the intensity of a reverse operation of the heat exchanger in the evaporator operation can be significantly shortened or can optimally be dispensed with a reverse operation, since heat is otherwise coupled via the heat exchanger device into the heat exchanger in the evaporator operation or the refrigerant flowing through it. that is sufficient for its thawing.

It is thus provided a heat exchange in the heat exchanger in the evaporator operation. A defrosting of an iced heat exchanger in the evaporator operation can by supplying a coolant as a heat exchange medium respectively. The heat exchange medium can eg cooling water or a

Cooling water-glycol mixture be. As a refrigerant to flow through the

Heat exchanger in the evaporator operation is in this case natural refrigerant, in particular CO ₂ , R744 or ammonia, the latter, however, less suitable for use in a vehicle, or synthetic refrigerant such as halogenated or non-halogenated hydrocarbons, such as R134a / HFO 1, 2 , 3,4 yf. Defrosting the heat exchanger in evaporator operation is possible by supplying heat through the heat exchanger medium to the heat exchanger in evaporator operation. There are vehicle heat pumps with a heat source in the form of air or ambient heat. Further, it is possible to use cooling water as a heat source. The latter could be with electric vehicles due to compared with vehicles with

Internal combustion engine lower amount of heat may not be sufficient. When defrosting the heat exchanger in the

Evaporator operation would also transfer heat to the refrigerant, this could therefore prove to be disadvantageous for the defrosting of the heat exchanger, as this then takes a longer time or the available amount of heat then may not be sufficient. As already mentioned, it proves to be advantageous, if necessary, for a short time the refrigerant is not through the

To flow heat exchanger.

Furthermore, it proves to be further advantageous to design the heat exchanger device such that it extends along the refrigerant heat exchanger or a part or region of the refrigerant heat exchanger, in particular a section of at least one of the refrigerant

permeable or flowed through pipe and / or a frame and / or housing of the heat exchanger in the evaporator operation extends. Here, at least one surface of the at least one pipe of the

Heat exchanger be provided in the evaporator operation magnifying element. For example, the at least one pipeline can be provided on the outside with ribs which extend as a stocking along at least part of the pipeline of the heat exchanger in the evaporator operation. The at least one pipe of the heat exchanger in the evaporator operation is in particular designed as a pipe line, wherein through the intermediate spaces between the individual sections of the pipe coil air can flow through. When flowing air through the interstices of the outside with the ribs pipe coil of the heat exchanger in the evaporator operation in cross flow to the refrigerant flowing through the pipe coil refrigerant is a particularly good heat transfer due to the larger

Heat transfer surface possible. Depending on whether the heat exchanger as a heat exchanger in the evaporator mode or in the heat pump mode as

Capacitor is operated, the refrigerant evaporates as it flows past the air on the pipe or with the at least one surface enlarging element, such as outside ribs, provided surface or it condenses there. The risk of icing of the heat exchanger in

Evaporator operation, as already mentioned, especially at

Evaporation temperatures below 0 ° C.

The extending along at least one section

Heat exchanger device is advantageous for passing a

Heat exchange medium formed like a conduit or may comprise at least one pipe. Further advantageously, the heat exchanger device is arranged above and / or below and / or laterally of the heat exchanger in the evaporator operation in heat exchange or heat-conducting contact with this and / or the refrigerant flowing through it or flowing through it. Advantageously, coolant, in particular cooling water or cooling water, can be passed through a further medium, in particular a cooling water / glycol mixture, through the heat exchanger device. The heat exchanger device can thus in particular in the form of a pipe on the top and / or bottom and / or side of the coiled tubing heat exchanger, which can operate in the evaporator operation extend, wherein the at least one pipe of the heat exchanger device in. Heat exchanging or

thermally conductive contact with the at least one pipe of the

Heat exchanger is.

In order to fasten the conduit-like or in the form of a pipe or at least one such comprehensive heat exchanger device to the heat exchanger in the evaporator operation or a housing of this heat exchanger can, is advantageously at least one fastening device for securing the heat exchanger device in heat exchange or heat-conducting contact to the heat exchanger in the evaporator operation and / or provided by this flowing or flowing refrigerant therethrough. The

Fastening device may be formed in particular like a clip, to clipping the heat exchanger device on the housing or frame of the heat exchanger in heat exchange or heat-conducting contact with the at least one pipe or through which it flows

Refrigerant to provide. For example, the at least one pipe of the heat exchanger device in a frame, such as a plastic frame, which aufgen on the housing or the frame of the heat exchanger or

can be clipped, arranged and a contact or a heat transfer to the housing or the frame of the heat exchanger in the evaporator operation, which / consists in particular of aluminum, thus good thermal conductivity, allow. Advantageously, the heat exchanger device or its frame and / or fastening device is thus arranged and fastened to the housing or frame of the heat exchanger in the evaporator mode at the top and / or bottom and / or laterally thereof, but advantageously neither before nor behind, in order not to allow air to flow through it to block. For supplying heat for defrosting the heat exchanger in the evaporator operation is thus only, for example, a single component, such as a pipeline of the

Heat exchanger device provided, over this already the defrosting or thawing of the heat exchanger is made possible in the evaporator mode, without requiring large amounts of energy. The range, in particular, of a vehicle equipped with such a device with electric drive is thus not affected or at least hardly negatively.

The cost of a possibly provided reversing operation can be reduced with provision of the heat exchanger device or the temperature difference can be reduced. By providing the heat exchanger device, the duration of the reversing operation can be reduced or it is possible to switch the system at least not as often as previously in the reverse operation, in the event that this despite provision of the heat exchanger device continues to make sense or

required appears. The provision of the device for defrosting can not only be used advantageously in vehicles with electric drive, but also in vehicles with internal combustion engine and conventional cooling circuit or hybrid / range extender vehicles, thereby extending the range or provide for certain driving cycles, thus not requiring an electric heater for defrosting the heat exchanger in the evaporator operation and to provide no additional electrical energy for this.

In vehicles with electric drive or vehicles that are powered solely by an electric drive with traction battery, so pure battery electric, also the waste heat of components of the vehicle that generate heat, also advantageous for defrosting the heat exchanger in

Evaporator operation can be used. Here, the refrigeration system is part of such a vehicle with heat-generating components, such as a traction battery and power electronics, wherein waste heat at least one of

heat generating components of the vehicle over the

Heat exchanger device to the through the heat exchanger in

Evaporator operation flowing refrigerant is discharged to defrost the • heat exchanger in the evaporator operation. The traction battery, as well

Electric motor, an AC / DC converter with power electronics, etc. can

Be components of a coolant circuit. The heating in operation components are flowing through the flowing in the coolant circuit

Cooling cooled, these components may be connected in the coolant circuit in series or in parallel. The cooling water heated after flowing through the traction battery for the cooling thereof can be passed through the heat exchanger device, wherein the heat extracted by this heat can be supplied to the heat exchanger in the evaporator operation in the refrigerant circuit to defrost this. The heat exchanger device is therefore in heat-conducting contact with the heat exchanger in

Evaporator mode or its housing and / or frame and / or

Pipe (s) and / or the refrigerant flowing therethrough. Thus, the waste heat of the few heat-generating components can be used in a vehicle with electric drive or traction battery for defrosting the heat exchanger in the evaporator operation. Thus, it is thus the coolant circuit or in particular the cooling water circuit with the refrigeration system, which is operated or operated as a heat pump, or the system that includes the heat exchanger in the evaporator operation, interconnected for the purpose of heat exchange. The coolant circuit or cooling water circuit absorbs heat from the coolant

Cooling water circuit connected components, such as in an electric vehicle from the traction battery, an electric motor, an AC / DC converter with power electronics, etc. Preferably, the heat or waste heat of a component is used to defrost the heat exchanger, which is not the

Internal combustion engine of an internal combustion engine vehicle is.

In a vehicle, in particular land vehicle, with at least one

Electric drive and / or at least one traction battery and with at least one refrigeration system with at least one heat exchanger in the evaporator operation, which tends to freeze in at least one operating mode for icing, it is also advantageously possible, the heat exchanger device parallel and / or longitudinal to a radiator of the coolant circuit the vehicle and in heat exchange, in particular heat-conducting contact to switch with the heat exchanger to be deiced in the evaporator operation of the refrigerant circuit, in particular parallel and / or longitudinal to a radiator of the heat generating component of the vehicle. It is also possible to connect such a heat exchanger device in series with a cooler of the coolant circuit of the vehicle, in particular a heat-generating component of the vehicle, and in heat exchange, in particular heat-conducting contact with the heat exchanger to be deaerated in the evaporator operation of the refrigerant circuit. The

Heat exchanger device is particularly small in size, in order to be able to be provided even in confined space available, but still sufficient for heat transfer to the heat exchanger to be deiced in the evaporator operation. Advantageously, when providing a series connection, a bypass line for bridging the heat exchanger device is provided in order to enable operation without it. With provision of a

Parallel connection is a "bridging" of the heat exchanger device already by the parallel connection of the heat exchanger device and the Heat exchanger in evaporator operation possible. Also when arranging the

Heat exchanger device in a connectable and disconnectable path of the

Coolant circuit is a "bypass" by switching off the path,

For example, by pressing a switching valve, in a simple manner possible.

In each case, an additional heat exchanger device is thus provided which is in heat-conducting contact with the heat exchanger in the

Evaporator operation or the refrigerant which flows or can flow through the heat exchanger in the evaporator operation is provided to couple heat into the heat exchanger in the evaporator operation or the refrigerant of the heat exchanger in the evaporator operation and thereby the heat exchanger in

Evaporator operation to deice.

For a more detailed explanation of the invention are hereinafter

Embodiments of this will be described in more detail with reference to the drawings. These show in:

Figure 1 is a schematic view of a refrigeration system comprising a

Heat exchanger in evaporator operation of an air conditioner, in arrangement in a vehicle _*

FIG. 2 shows a schematic view of a heat exchanger in the evaporator mode with rib stocking on its pipeline coil,

3 is a schematic diagram of a heat exchanger in the evaporator operation with the outside rib stocking its pipe line and with inventive heat exchanger device on the top and bottom of the heat exchanger in the evaporator operation,

Figure 3a is a longitudinal sectional view taken along the line A-A through the

Heat exchanger in the evaporator operation according to Figure 3, in a broken view,

Figure 4 is a schematic diagram of a parallel connection of a small heat exchanger device according to the invention and a radiator of a

Coolant circuit comprising an electric motor and an AC / DC converter, arranged in a vehicle, Figure 5 is a schematic diagram of a vehicle with a small heat exchanger device according to the invention in parallel to a radiator provided coolant circuit, comprising a battery system that can be tempered either by a heater and a cooling device, and

Figure 6 is a schematic diagram of a vehicle with an inventive

small heat exchanger means in series with a cooler provided coolant circuit, wherein the heat exchanger means can be bridged by a bypass line.

1 shows a schematic sketch of a refrigeration system 1, arranged in a vehicle 100, which is suitable for operation in the air conditioning (AC) mode for cooling and in the heat pump (HP) mode for heat generation. The vehicle 100 is shown only schematically in FIGS. 1 and 4 to 6. It has a front side 101 and a rear side 102, wherein in the figures 1 and 4, only the front portion of the vehicle 100 with the

Front side 101 is indicated, while in the figures 5 and 6 each of the entire vehicle 100 is indicated with front 101 and rear side 102.

The refrigeration system comprises a heat exchanger 20, adjacent to which a heat exchanger device 55 of a coolant circuit 65 and a

Fan 3 are arranged for supplying and discharging air, and a compressor 10. Further, the refrigeration system comprises an air conditioner 4 and a HVAC unit with an evaporator 40, a condenser 41 and a fan or fan 42. The refrigeration system 1 comprises Furthermore, a collector 5, two switching valves 6, 7 and two expansion valves 8, 9. The heat exchanger 20 of the refrigeration system, depending on the refrigerant used as a condenser or gas cooler, both condenser and gas cooler for heat absorption from the ambient air, through this flows, serve, or as

Evaporators are operated for heat absorption in the heating mode

Refrigeration system. The refrigeration system 1 always comprises an evaporator operation, in the mode for refrigeration (air conditioning mode) serves to evaporate refrigerant, the evaporator 40, in the mode for heat generation (heat pump mode) is used for this purpose, the heat exchanger 20. refrigerant decreases in the latter Evaporator operation (heat pump mode) when the heat exchanger 20 as

Operate evaporator, thus is in the evaporator operation, heat when flowing through this and evaporates there. In the air conditioning mode, the heat exchanger 20 is in the condenser mode in which heat is dissipated to generate cold. In the air conditioning mode, the evaporator 40 serves to absorb heat and to evaporate the refrigerant as it flows through the evaporator 40.

In the illustrated refrigerant circuit 66 of the refrigeration system 1 is the through the lines 11, the individual components mentioned above the

Refrigeration system 1 communicate with each other, compressed refrigerant first compressed in the compressor 10. The refrigerant is then gaseous and is under a high pressure. In winter operation (heat pump mode), the refrigerant then passes through the condenser 41, in which it condenses with the release of heat to the air (in the Ig-ph diagram, the wet steam area) or supercritically cooled further (in the Ig-ph diagram gas area ), depending on the used

Refrigerant. The then liquid, but still under high pressure refrigerant then flows through the expansion valve 8. Das

Expansion valve is used to reduce the pressure by increasing the volume, so that the refrigerant behind the expansion valve 8 is in a liquid state and is under, a low pressure. Downstream of the expansion valve 8 is the heat exchanger 20. In this winter, heat from a stream of air flowing therethrough into the system, ie the refrigerant, is introduced via the heat exchanger 20. Downstream of this, the second switching valve 7 is provided, via which the refrigerant is supplied to the collector 5 and from there back to the compressor 10. In winter operation of the refrigeration system, heat is thus coupled into the refrigerant via the heat exchanger 20, the refrigerant evaporating in the heat exchanger 20 and accordingly prone to freezing in this operating mode.

In summer mode (air conditioning mode) flows through the refrigerant after the compressor 10, the switching valve 6. The condenser 41 is flowed through during summer without heat dissipation, especially at

corresponding flap control in the HVAC unit, without air flow there. Downstream of the switching valve 6, the heat exchanger 20. In this heat is released to the outside during summer operation. He works in the

Capacitor operation. Downstream of this, the second switching valve 7 is provided, via which the refrigerant in the summer mode on the second

Expansion valve 9 is supplied to the evaporator 40. In summer operation takes place when passing the refrigerant through the expansion valve 9 only there

Pressure reduction and subsequent evaporation in the evaporator 40, wherein the refrigerant changes its state of matter from liquid to gaseous while receiving heat from the environment and release of evaporative cooling. After passing through the evaporator 40, the refrigerant first passes into the collector 5 during summer operation, before it returns to the compressor 0 from there. In summer operation, heat is thus discharged from the refrigerant via the heat exchanger 20 (condenser operation), so that the heat exchanger 20 normally does not tend to freeze.

Located in the heat pump mode (heat pump mode) of the refrigeration system of the heat exchanger 20 in the evaporator mode, which absorbs heat from the environment, the heat exchanger 20 is hereinafter referred to as a heat exchanger in

Evaporator operation called. In order to allow heat absorption even at low outside temperatures, the evaporation temperatures are sometimes well below 0 ° C. Accordingly, the sinks also

Surface temperature of the heat exchanger 20 in the evaporator operation below the freezing point of water, which leads to ice formation on the surface. To counteract this or to be able to defrost an iced heat exchanger 20 in the evaporator operation again, the heat exchanger 20 is provided in the evaporator operation with the at least one heat exchanger device 55, as they

is shown in particular in Figures 1 to 6.

As illustrated in FIGS. 2 and 3, in the evaporator operation, the heat exchanger 20 shown there has a pipe coil 21, which is provided on the outside with ribs 22, as in the detail view of FIG

Piping to see in Figure 2. The pipe coil 21 is in a

Frame construction 23 of the heat exchanger 20 in the evaporator operation

arranged, these two side frame parts 24, 25 and a middle part 26 has. The side frame parts have outside attachment eyelets 27 for securing the heat exchanger in the evaporator operation in the vehicle 100, in particular in a land vehicle, such as an electric vehicle, which is not shown in Figure 2, however. The pipe coil 21 is coiled several times in the frame construction 23 of the heat exchanger 20 in FIG

Evaporator operation arranged and has an inlet opening 28 and a

Outlet opening 29 on. In the inlet opening 28, refrigerant 30, here illustrated by the arrow, flows in and out through the outlet opening 29. Further, air 31, illustrated by arrows, passed across the heat exchanger 20 in the evaporator operation, ie in cross-flow to the

flowing refrigerant 30. By providing the ribs 22 on the

Outside of the pipe coil 21 is on the one hand, although the to

Flowing through the air 31 reduces available space between the individual branches of the pipe coil 21, by the provision of the ribs 21, however, icing may be difficult and thawing of a

Furthermore, an expanding ice layer on the ribs 22 will be thinner than if it were built up on a continuous surface, so that these subsequently also possibly easier to solve again. A thinner layer of ice hinders the operation of the heat exchanger 20 in the. Evaporator operation also less strong than a thick layer of ice, since the heat transfer is better for a thinner layer of ice than for a thick.

As shown in Figure 3, 3a, a heat exchanger device 12 in the form of two parallel to the longitudinal extension of the pipe coil 21 and the heat exchanger 20 in the evaporator operation extending pipes 120, 121 provided in heat-conducting contact with the heat exchanger in the evaporator operation or the pipe coil 21. The two pipes 120, 121 are connected to each other via a piping system 122. By the

Pipe system 122, coolant 123 may be introduced into the two pipes 120, 121. This is illustrated in Figure 3 by an arrow. The two pipes 120, 121 each have a housing 124, 125 surrounding them on the outside. This particular housing is made in particular of plastic and serves to connect to the frame structure 23 of the heat exchanger 20 in the evaporator operation. For example, the respective housing 124 or 125 of the heat exchanger device 12 to the

Frame structure 23 be clipped or be, as indicated in Figure 3a. Other forms of attachment, in particular releasable attachment, are of course possible here. In each case, the respective pipe 120 or 121 as close as possible in heat exchange, in particular heat-conducting contact with the frame construction 22 of the heat exchanger 20 in

Evaporator operation brought to heat transfer from the

Cooling water to the frame structure 23 and the pipe snake 21 of the heat exchanger 20 recorded herein in the evaporator operation to cause thawing, this being additionally by the ribs 22, the

Piping coil 21 surrounded, can be supported, as explained above.

About the heat exchanger device 55 can be in a to be deiced

Heat exchangers 20 are also coupled in the evaporator operation, such heat, which as waste heat in heat-generating components of a

Vehicle, such as an electric vehicle, occurs and over the cooling water used for cooling this respective component through the

Heat exchanger device is guided. The heat removed there is subsequently provided to the heat exchanger 20 in the evaporator operation to make the desired deicing. Such

heat generating component, for example, a pure battery electric powered vehicle may be its traction battery. The battery,

Electric motor and AC / DC converter can be connected in series or parallel to each other. Figures 4, 5 and 6 show two examples of such a circuit, in Figure 4, an electric motor 50 with an AC / DC converter 51 in series and with a charger 52 is connected in parallel. The AC / DC converter 51 may be part of a unit that further comprises power electronics. AC / DC converter and power electronics are advantageously arranged in the vicinity of the electric motor 50, which serves to drive the vehicle 100. For operation in the Standstill in which the electric motor 50 is not running, the charger 52 is parallel to the electric motor 50 and the AC / DC converter 51 together with the

Power electronics switched. Switching between the charger 52 and the operation with electric motor 50 and AC / DC converter 51 via a

Switching valve 53. The circuit shown in Figure 4 further comprises a radiator 54, the small heat exchanger device 55 is connected in parallel. One

Switching between these two components of the circuit is possible via a second switching valve 56. For transporting the medium through a conduit system 58 connecting the said components

Coolant circuit 65 is also a pumping device 57 is provided.

In contrast to the embodiment according to FIG. 4, the coolant circuit 65 according to FIGS. 5 and 6 comprises a battery system 59 instead of the electric motor 50 and the AC / DC converter or the unit therefrom and the power electronics Cooling device 61 is arranged and optionally switched on and off via a switching valve 62. For pumping the medium in a line system 63 interconnecting the individual components, a pump device 64 is provided.

The (small) heat exchanger device 55, which is connected in parallel with the cooler 54 of the coolant circuit 65, serves as additional

Heat exchanger device for transferring heat to the heat exchanger 20 not shown in Figures 4, 5 and 6 in the evaporator operation of

Refrigerant circuit. It is therefore advantageous in heat exchange,

in particular heat-conducting contact, even with the enteisenden

Heat exchanger 20 in the evaporator operation. The radiator 54 serves to cool the battery system 59. The radiator 54 according to FIG. 4 serves to cool the battery

Electronic components, ie in particular the AC / DC converter 51 with

Power electronics and the electric drive in the form of the electric motor 50 and the AC / DC converter 51 and the charger 52. The small

Heat exchange device 55 removes the heat absorbed during cooling in the coolant and transfers it to the to be de-ice

Heat exchanger 20 in the evaporator operation. Thus, in the coolant circuit 65 falling heat through the small heat exchanger device 55 the Coolant circuit 65 removed and the heat exchanger 20 in the evaporator operation of the refrigerant circuit 66 (see, for example, Figure 1) are supplied to serve for thawing or defrosting of the heat exchanger 20 in the evaporator operation.

In contrast to the embodiment according to FIG. 5, in the heat exchanger device 55 shown in FIG. 6 in series with the radiator 54 of the coolant circuit of the vehicle and in heat exchange, in particular heat-conducting contact, with the heat exchanger 20 to be deiced

Evaporator operation of the refrigerant circuit connected or here in series with a cooler 54 of the heat-generating components 59, 60 of the

Vehicle 100. In order to bridge the heat exchanger device 55, if this is not to be used, a bypass line 67 is provided. Alternatively, the heat exchanger device 55 could also be in a switchable by, for example, a switching valve and connectable path of the

Coolant circuit 6 may be arranged, whereby also a "bridging" of the heat exchanger device is made possible.

Refrigerant for flowing, inter alia, the heat exchanger 20 in

Evaporator operation can be in particular CO ₂ , R134a / HFO 1, 2,3,4 yf, ammonia and halogenated medium, in particular fluorinated,. Or non-halogenated medium. For coupling heat into the heat exchanger 20 to be deiced in the evaporator operation, the heat exchanger device 12 or 55 of a coolant, such as a mixture of cooling water and a

Heat exchange medium, such as glycol, are flowed through. By supplying a corresponding heat exchanger medium, in particular by the

Heat exchanger device 12, it is possible to remove an ice layer on the outside of the heat exchanger 20 in the evaporator operation.

For energy-efficient deicing, in particular a heat exchanger in the

Evaporator operation of a refrigeration system of, for example, a vehicle, such as a land vehicle, may thus include various types of

Heat exchanger devices are used, which extract heat in particular from the coolant of the coolant circuit and the heat exchanger in the Supply evaporator operation by advantageously arranging the

Heat exchanger device in heat exchange, in particular heat-conducting contact with the heat exchanger to be deaerated in the evaporator operation and / or the refrigerant to be deaerated by the heat exchanger to be deiced in the evaporator operation or flowing.

In addition to the variants of devices and methods for defrosting a heat exchanger in the evaporator operation of a refrigeration system described above and shown in the embodiments, the heat exchanger can be flowed through or flowed through with refrigerant in the evaporator operation, numerous other, even any combinations of the aforementioned embodiments can be provided in which in each case such a heat exchanger device for coupling heat from a coolant circuit and coupling heat into the heat exchanger to be deiced in the evaporator operation or the refrigerant flowing through it are provided.

LIST OF REFERENCE NUMBERS

1 refrigeration system

3 fans

4 air conditioner / HVAC unit

5 collectors

6 switching valve

7 switching valve

8 expansion valve

9 expansion valve

10 compressors

11 line

12 heat exchanger device

20 heat exchangers (in evaporator mode)

21 pipe line

22 rib

23 frame construction

24 side frame part

25 side frame part

26 middle part

27 fixing lugs

28 inlet opening

29 outlet opening

30 refrigerants (arrow)

31 air (arrow)

40 evaporators

41 condenser / gas cooler

42 fan / fan

50 electric motor

51 AC / DC converters

52 charger

53 switching valve

54 coolers

55 (small) heat exchanger device Switching valve Pumping device Cable system Battery system Heating device Cooling device Switching valve Line system Pumping device Coolant circuit Refrigerant circuit Bypass line Vehicle

front

rear side

pipeline

Pipe piping system coolant (arrow) housing

casing

Claims

claims

1. Device for deicing a heat exchanger in the evaporator operation (20) of a refrigeration system (1), wherein the heat exchanger in

Evaporator operation (20) as part of a refrigerant circuit (66) with

Refrigerant (30) can be flowed through or through, the refrigeration system (1) is operated or operated in heat pump mode and wherein at least a first coolant circuit (65) of a vehicle is provided, characterized in that

the device is a heat exchanger device (12, 55) which is arranged in a second coolant circuit or a separate, connectable and disconnectable path of the at least one first coolant circuit (65) and can be provided or provided in heat exchange with the heat exchanger in the evaporator operation (20).

2. Device according to claim 1,

characterized in that

for switching on and off the path of the coolant circuit (65) at least one switching valve is provided.

3. Device according to claim 1 or 2,

characterized in that

the heat exchanger means for passing a

Heat exchange medium (123) is formed like a conduit or at least one pipe (120,121) and includes and / or below and / or laterally of the heat exchanger in the evaporator operation (20) in

Heat exchange, in particular heat-conducting contact, with this and / or the flow through or through this ...

flowing refrigerant (30) is arranged.

4. Device according to one of the preceding claims,

characterized in that

at least one coolant is provided as a heat exchange medium (123), in particular cooling water or a cooling water / glycol mixture, and the Refrigerant (30) is a natural refrigerant, in particular CO ₂ , R744, or a synthetic refrigerant, in particular halogenated or non-halogenated hydrocarbons, such as R134a or HFO 1, 2,3,4 yf.

5. Device according to one of the preceding claims,

characterized in that

the heat exchanger means (12,55) along the refrigerant heat exchanger or a portion or region of the refrigerant heat exchanger, in particular a portion of at least one of the refrigerant (30) through-flow or through-flow pipe (21) and / or a frame (23) and / or housing of the heat exchanger in the evaporator operation (20) extends.

6. Device according to one of claims 3 to 5,

characterized in that

at least one fastening device for fastening the

Heat exchanger device (12,55) in heat exchange, in particular heat-conducting contact, is provided to the heat exchanger in the evaporator operation (20) and / or through this flowing or through flowing refrigerant (30).

7. Device according to claim 6,

characterized in that

the fastening device is designed clip-like for clipping the heat exchanger device (12) on a housing or frame (23) of the heat exchanger in the evaporator operation (20).

8. A method for deicing a heat exchanger in the evaporator operation (20) of a heat pump mode operable or operated refrigeration system (1), wherein the heat exchanger as part of a refrigerant circuit (66) in the evaporator operation (20) with refrigerant (30) is flowed through,

characterized in that heat is taken from a coolant circuit (65) by a heat exchanger device (12, 55) and is transferred to the heat exchanger in the

Evaporator mode (20) is supplied.

9. The method according to claim 8,

characterized in that

the heat a frame (23) and / or housing and / or a

Ice layer on the heat exchanger in the evaporator mode (20) is supplied.

10. The method according to claim 8 or 9,

characterized in that

during the defrosting of the heat exchanger in the evaporator operation (20), a flow through the same with refrigerant (30) is prevented.

11. Vehicle (100), in particular land vehicle, with at least one

Electric drive (50) and / or at least one traction battery (59) and with at least one in the heat pump mode operable or operated refrigeration system (1) with at least one heat exchanger in the

Evaporator operation (20), which as part of a refrigerant circuit (66) with refrigerant (30) is flowed through or through, and with at least a first coolant circuit (65),

characterized in that

at least one heat exchanger device (12, 55), which is arranged in a second coolant circuit or a separate, connectable and disconnectable path of the at least one first coolant circuit (65), in FIG

Heat exchange is provided to the heat exchanger in the evaporator operation (20).

12. vehicle (100) according to claim 11,

characterized in that

at least one heat-generating component is provided, in particular the traction battery (59), an electric motor (50),

Power electronics, and / or other or other heat-generating Components, and the at least one heat exchange means (55) in a coolant circuit (65) for controlling the temperature of the heat generating component (50,51, 52,59) is arranged and for defrosting the

Heat exchanger in the evaporator operation (20) the waste heat of the at least one heat generating component (50,51, 52,59) of the vehicle (100) to the heat exchanger in the evaporator operation (20) supplies.

13. vehicle (100) according to claim 11 or 12,

characterized in that

the heat exchanger device (55) parallel and / or longitudinally to a cooler (54) of the at least one first coolant circuit (65) of the vehicle (100) and in heat exchange, in particular heat-conducting contact, with the heat exchanger to be deaerated in the evaporator operation (20) of the refrigerant circuit ( 66), in particular parallel and / or longitudinally connected to a cooler (54) of the at least one heat-generating component (50, 51, 52, 59) of the vehicle (100).

14. Vehicle (100) according to claim 11 or 12,

characterized in that

the heat exchanger device (55) in series with a cooler (54) of the at least one first coolant circuit (65) of the vehicle (100) and in heat exchange, in particular heat - conducting contact with the heat exchanger to be deiced in the evaporator operation (20) of

Refrigerant circuit (66), in particular in series with a cooler (54) of the at least one heat-generating component (50,51, 52,59,60) of the vehicle (100) is connected.

15. Vehicle (100) according to claim 14,

characterized in that

a bypass line (67) is provided for bridging the heat exchanger device (55) or the heat exchanger device is arranged in a path of the coolant circuit (65) which can be switched on and off.