DK2994326T3 - Serviceudstyr til vedligeholdelse af køretøjsklimaanlæg samt fremgangsmåde til drift af et sådant serviceudstyr - Google Patents

Description

SERVICE DEVICE FOR THE MAINTENANCE OF VEHICLE AIR-CONDITIONING SYSTEMS AND METHOD FOR OPERATING A SERVICE DEVICE OF THIS TYPE

AREA OF THE INVENTION

The invention relates to a service device for the maintenance of vehicle air-conditioning systems and a method for operating a service device of this type according to the generic part of Claims 1 and 8. Accordingly, a generic service device comprises a coolant supply and a first separation stage feeding the coolant supply and for the separation of coolant and any non-condensable gases from compressor oil and any additives. As a result, the compressor oil and liquid additives of the mixture in the first separation stage of the service device can be separated from a coolant/non-condensable gases/compressor oil mixture of a vehicle air-conditioning system and the coolant cleansed of compressor oil and any noncondensable gases in the coolant supply can be collected. Therefore, the separation stage substantially separates compressor oil from the coolant/non-condensable gases. The coolant/compressor oil mixture can be heated by constructing the oil separator as a heat exchanger in such a manner that the coolant is completely evaporated and no liquid components pass into the compressor connected in downstream. The compressor oil, which is as a rule contaminated and still liquid, is separately collected.

TECHNOLOGICAL BACKKGROUND A generic service device for the maintenance of vehicle air-conditioning systems is known from WO 2011/063961 A1 by the same applicant, filed under the application number PCT/EP2010/007155 on November 25, 2010 and published on June 03, 2011, which is included in the present disclosure in its totality by reference.

The block wiring diagram according to figure 1 shows the basic construction of a service device for vehicle air-conditioning systems as is preferred by WO 2011/063961 A1. According to it, service connection connectors 109A, 109B are provided for the connection to the coolant/compression circuit of a vehicle air-conditioning system (not shown here) for its maintenance, in particular to empty it and refill it. There is a fluidic connection by pressure hoses 111 A, 111B to a first switching valve block 130 whose function will be explained further below. The switching valve block 130 is fluidically connected on the one hand to a separation stage 140 shown on the right in the image and which will be explained further below, and on the other hand to a vacuum unit 150 (on the left in the image below) which will also be explained further below. A low-pressure manometer 126A and a high-pressure manometer 126B on the switching valve block 130 serve, among other things, to control the status and the function of the coolant-compressor oil circuit of the vehicle air-conditioning system. Furthermore, the switching valve block 130 is fluidically connected to a refilling system 119 for compressor oil and additives with weighing devices 117C and 117D for donors 119C, 119D, for example, for an additive for finding leaks or for fresh oil. The system pressure inside the switching block 130, which is significant after the beginning of the emptying of the fluid circuit for the system control, which will be explained further below, is monitored by a pressure sensor 131 connected to a collection line of the switching valve block 130 so that the system pressure, in particular the coolant pressure of the vehicle air-conditioning system is monitored so that, among other things, the subsequently explained circuit systems (separation stage 140 and vacuum unit 150 and associated valve cir-cuits) can be controlled. The lines associated with the circuit of the separation stage 140 are shown in dots inside the switching valve block 130. In contrast thereto, the lines associated with the vacuum unit 150 are shown in dot-dash lines in order to be able to better differentiate in the following the work phases of the system.

The functioning of the separation stage 140 is as follows: After the connection of the service connection connector 109A, 109B to the corresponding ports of the vehicle air-conditioning system and the releasing of the corresponding valves LP, HP, CX2 of the switching valve block 130, the system pressure of the vehicle air-conditioning system is available for transferring a first part of the contents of the coolant compressor oil circuit of the vehicle air-conditioning system into the separation stage 140. This system pressure is already about 3 bars absolute at 0°C and is already at a magnitude of 6 bars absolute at about 20°C, so that the transport of coolant-compressor oil mixture into the separation stage 140 even takes place automatically at first. Otherwise, this transporting is supported, as explained further below, by operating the compressor 112 and is kept going later with a falling system pressure. The coolant-compressor oil mixture passes from the switching valve block 130 via a coarse filter 114 and a constant pressure valve 141 adjusted to about 3.5 bars absolute into a double-jacket heat exchanger 142, namely, into its inner container 142A. There, the volatile components are evaporated and the gaseous phase passes via a line 146A into a gas dryer 146 and from there into the compressor 112.

The double-jacket heat exchanger 142 simultaneously serves as a separator for liquid components of the coolant-compressor oil mixture, which basically concerns the compressor oil, optionally contained additives and residual a-mounts of the coolant still bound in the compressor oil. This liquid phase is supplied via an oil outlet valve 116A to an old oil container 116. The accumulating amounts can be registered by a weighing device 117A which also weighs the container.

The compressor 112 ensures that the coolant is compressed at its output side to a pressure of up to, e.g., 19 bars absolute. A compressor emergency valve 112A limits the pressure to 19 bars as a rule. Since the lubricating oil of the compressor also passes into the compressed coolant, it is separated in an oil separator 112B and is returned to the lubrication of the compressor 112 via a capillary tube 112C which acts as a pressure throttle. The coolant, which is compressed, dried and freed of compressor oil and additives, passes into a heating coil 142C located in the gas chamber of the inner container 142A of the double-jacket heat exchanger 142. As a result, the compression heat contained in the compressed coolant can be given off in order to evaporate as far as possible the coolant/compressor oil mixture arriving fresh out of the vehicle air-conditioning system on the cold side. From the heating coil 142C the cleaned (recycled) coolant first passes into the outer jacket area (outer container 142B) of the double-jacket heat exchanger 142 and from there via a valve block 142D and a connection hose 129 to the coolant supply 115 (supply container). The supply container is weighed with contents by a weighing device 117B. The supply container also carries a coolant liquefier 115A, which is advantageously also weighed at the same time and in which the coolant standing under compression pressure is condensed in order to pass in liquid form into the coolant supply 115. The separator 112B as well as the coolant supply 115 are therefore designed as so-called pressure containers. The pressure in the coolant supply 115 is secured against excess by a valve 115B because the gaseous phase of non-condensable gasses forming above the liquid level must be let off in a regulated manner after a certain excess pressure of, e.g., 16 bars for safety reasons. This can also take place in a non-automatic manner by an operator via a handle 115C.

The liquid coolant passes via a non-return valve 115D and a standpipe 115E into the liquid area of the coolant supply 115. In order to be able to refill the vehicle air-conditioning system with coolant, liquid coolant passes via the standpipe 115E, a valve 115F and a connection line 115G back into the switching valve block 130.

As soon as the vehicle air-conditioning system has been emptied to the extent that the compressor 112 can no longer draw in sufficient coolant/compressor oil mixture on its low-pressure side, which can absolutely be the case at a pressure of 0.7 bars, the vacuum unit 150 is put in operation by actuating the corresponding valves. In this manner, other gas components are drawn in from the liquid circuit of the vehicle air-conditioning system via the collection line of the switching valve block 130 by the vacuum pump 113. From the output side of the vacuum pump 113 this gas or gaseous mixture passes via a (second) switching valve block 151 and magnetic valves VC2 back to the switching valve block 130 and from there into the connection line 143 which fluidically couples the switching valve block 130 to the separation stage 140. The gas amounts transported by the vacuum pump 113 out of the vehicle air-conditioning system are now treated in the separation stage 140 exactly like the amounts of coolant/compressor oil mixture exiting independently at the beginning of the emptying process from the vehicle air-conditioning system. The difference from the first phase, designated here as flowoff phase, is that no liquid components, that is, substantially gaseous coolants or any air from the vehicle air-conditioning system, are drawn in from the vehicle air-conditioning system on account of the previous flowoff phase supported by the compressor 112. At first, relatively large amounts of gas are to be managed whereas toward the end of the second phase, designated here as the evacuation phase, the gas amounts become clearly less. At an inlet pressure of about 1 mbar or after the passage of a fixed, previously set process time the evacuation process is ended.

The gas pressure generated by the vacuum pump 113 on its output side should not exceed a magnitude of 2 bars absolute in order not to damage the vacuum pump 113. For the pressure control the switching valve block 151 connected in downstream from the vacuum pump is associated with a pressure switch 151A with the aid of which the vacuum pump 113 cuts off when an output pressure of e.g. 2 bars is exceeded until the output pressure has again dropped in a corresponding manner so that the vacuum pump 113 can be cut in again.

Since the service device is used not only for drawing off and refilling the vehicle air-conditioning system in normal maintenance operation but also for repairs to air-conditioning systems, e.g., component replacement, the switching valve block 151 connected in downstream from the vacuum pump 113 is provided with an outlet valve VC3 which can run, e.g., to the atmosphere. Therefore, if only air is drawn off from the repaired vehicle air-conditioning system for a subsequent refilling, it does not pass into the separation stage 140.

Therefore, WO 20011/063961 A1 provides, among other things, monitoring the pressure in the coolant supply 115 and letting off in a regulated manner the gaseous phase of non-condensed and non-condensable gases forming above the liquid level after a certain excess pressure of, e.g., 16 bars for safety reasons. In such a supply container the separated coolant is present as a rule in liquefied form and the gases above the coolant liquid level which are not condensable under the prevailing conditions of pressure and temperature also comprise certain amounts of coolant. If appreciable residual amounts of coolants accumulate in the gas phase in the supply container on account of the prevailing conditions of pressure and temperature, it is optionally provided to supply them via the vacuum pump 113 or, based on the inner pressure of the coolant supply container, back to the separation stage. The same can be carrier out with the non-condensed gaseous components which accumulate in the separation stage in gaseous form in the old oil container 116 connected in downstream from the oil separator, or with the residual coolant amounts which are still not dissolved in the compressor oil. US 5,598,714 discloses a service device for the maintenance of vehicle air-conditioning systems according to the generic part of Claim 1 in which a separation stage for separating on the one hand coolant and non-condensable gases from on the other hand compressor oil feeds a coolant supply. Another separating stage for separating coolant on the one hand from non-condensable gases on the other hand is fed in the known device by the gaseous phase of the coolant supply and comprises an uncooled intermediate container. A baffle plate in the intermediate container assists in the separation in such a manner that coolant settles on the bottom of the intermediate container and non-condensable gas rises upward in the container.

In the device known from US 5,167,126, means for heating is provided on an intermediate container.

Also, a service device for maintaining vehicle air-conditioning systems is known from US 5, 582,019 in which an intermediate container for the coolant is not cooled.

PRESENTATION OF THE INVENTION

It was found that the amount of coolant in the gas volume above the liquid level of the coolant supply in a generic service device for vehicle air-conditioning systems can be so significant that it would be desirable or even required for reasons of cost and/or of safety not to discharge these residual coolant amounts into the environmental atmosphere. In order to achieve this, the suggestion of guiding the noncondensable gases purposely discharged from the coolant supply back to the separating stage is basically suited for solving the problem. However, one of the difficulties is that all non-condensable gases, in particular air, must be run in the circuit through the separating stage in this way. There is no sink for noncondensable gases.

The invention presented in the Claims 1 and 8 solves this problem. In a method according to the invention for maintaining a vehicle air-conditioning system, in particular with a service device according to Claim 1, a mixture of coolants/non-condensable gases/compressor oil of the vehicle air-conditioning system is conducted - as is known - into a service device, the compressor oil of the mixture is separated in a first separation stage of the service device, and the mixture of coolant/non-condensable gases cleaned of the compressor oil is collected in a coolant supply. According to the invention the coolant/non-condensable gaseous mixture is conducted out of the coolant supply into an intermediate container and the gaseous coolant is cooled off in the intermediate container until condensation. According to a first aspect, the present invention can provide separating the gas volumes discharged from the gaseous phase of the coolant supply container from time to time under appropriate pressure conditions in a separate, second separation stage by cooling them off in an intermediate container for non-condensed gases into a gaseous phase comprising non-condensable gases and a liquid phase comprising condensed coolant, preferably in batches. The gaseous phase in the intermediate container can subsequently be discharged e.g. into the environment down to a low residual pressure which is preferably above the environmental atmosphere. The liquid phase accumulating in the intermediate container can be supplied back to the coolant circuit, preferably to the coolant supply, in a suitable manner. According to the invention, the service device therefore comprises a second separating stage which is supplied from the coolant supply, in particular from its gaseous phase and which stage has an intermediate container for separating coolant and non-condensable gases. The second separating stage has the basic task of spatially separating the condensable coolant from the non-condensable gases.

It turned out that an efficient “sink” for non-condensable gases is created in the previously described manner which contains significantly fewer remnants of still gaseous coolant than the gaseous phase in the coolant supply of the service device for vehicle air-conditioning systems.

It is now possible to carry out the invention in several ways: thus, it can be advantageous to re-evaporate the liquid phase from the intermediate container for non-condensed gases, meaning the “fully condensed” coolant, following a complete or partial discharging of the gaseous atmosphere in order to be able to substantially discharge it, remove it by suction or expel it as a gas in a simple manner from the intermediate container in this way.

In any case, it is advantageous to resupply the coolant amounts accumulating in the intermediate container, preferably batch-wise, to the coolant supply in condensed form. For this, device components of a separating stage for a coolant/compressor oil mixture which are described in the prior art according to WO 2011/063961 A1 are especially suitable. However, it is not necessary as a rule for this purpose to use the vacuum pump which is selectively provided in such a service device for vehicle air-conditioning systems. Their use is preferably eliminated.

The service device for the maintenance of vehicle air-conditioning systems, in particular for the replacement of a coolant/compressor oil mixture, serves at first to replace the coolant/compressor oil mixture but also to repair vehicle air-conditioning systems. Both replacement and repair are combined with the concept “maintenance”.

The term “non-condensable gases” denotes such gases which only condense under extreme conditions, therefore under extreme pressures and/or temperatures and as a rule penetrate in an undesired manner into the coolant/compressor oil circuit of the vehicle air-conditioning system. They are in particular air, which among other things can markedly reduce the efficiency of the air-conditioning system. A compressor can be used to on the one hand obtain the pressure necessary for the liquefying of coolant. Compression heat from the compressed gaseous mixture can be utilized in a heat exchanger.

The coolant supply can receive fresh coolant delivered by the producer but also or exclusively coolant which was reprocessed; it is collected in a coolant supply container and dispensed as needed to a vehicle air-conditioning system. As a rule, a liquid and a gaseous phase form in the coolant supply container. The liquid phase comprises in any case slightly contaminated coolant, in contrast to which the gaseous phase can also comprise, in addition to non-condensable gases, gaseous coolant which stands in a particular equilibrium with its liquid phase as a function of the pressure and the temperature.

It is now possible in various ways to bring about the condensing of the coolant components in the intermediate container for non-condensed / non-condensable gases. To this end, liquid coolant from the coolant supply is preferably evaporated in an evaporator such as an evaporator coil located on or especially preferably inside the intermediate container. The coolant evaporated here can subsequently be returned, in particular via the separation stage for the coolant/compressor oil mixture, re-liquefied and without residue to the coolant supply container in liquid form.

The intermediate container preferably contains means for the cooling for the condensation of the coolant. The coolant condenses and collects on the bottom of the intermediate container, in contrast to which, the non-condensable gases collect above the condensed coolant. The area in which the liquid coolant is typically located in the intermediate container can be designated as the liquid zone and the typical area of the non-condensed gases as the gaseous zone.

The coolant supply can have an outlet for the coolant/non-condensable gaseous mixture. This outlet serves for the further conduction of the coolant/non-condensable gaseous mixture to the separation stage, that is, in particular to the intermediate container. In a corresponding manner, the intermediate container can have an inlet for the coolant/non-condensable gaseous mixture from the coolant supply. This creates a connection between the coolant supply, in particular between the gaseous phase of the coolant supply, and the intermediate container. If the intermediate container has a first outlet for the non-condensable gases which leads in particular to the environmental atmosphere, a sink can be created in this manner for the non-condensable gases. The first outlet can be arranged in the gaseous zone, preferably in the upper area, and especially preferably at the upper end of the intermediate container. The non-condensable gases can be removed at first in this manner, if desired, from the intermediate container. This removal can be achieved by an excess pressure in the intermediate container but also with a vacuum produced outside of the intermediate container.

If the intermediate container comprises a second outlet provided for the coolant, the condensed coolant can be e.g. directly returned into the coolant supply or also directly into the vehicle air-conditioning system and/or into the first separation stage and/or into a second coolant supply. The second outlet can be arranged in the liquid zone, preferably in the lower area, and especially preferably at the lower end of the intermediate container. The coolant can be removed in this manner from the intermediate container due to gravity even if the non-condensable gases had already been discharged and a pressure compensation, e.g., with the surroundings, had been made. The lower the outlet is, the more completely the intermediate container can be emptied and the more effective the separating process is. If the non-condensable gases are still present in the intermediate container and an excess pressure prevails, a sensor, for example, can recognize when the cool ant completely ran out from or was expelled from the intermediate container and then bring about a valve closure. Therefore, the emptying sequence can also be changed.

If the coolant supply has an outlet for liquid coolant from the coolant supply, the liquid coolant can flow into an inlet of the intermediate container, preferably into an evaporator coil. The cold, liquid coolant cools the evaporator coil, which is preferably located inside the intermediate container and therefore cools the gaseous coolant/non-condensable gaseous mixture. Subsequently, the coolant transferred from the gaseous phase of the coolant supply into the intermediate container condenses while the components of non-condensable gases remain gaseous.

The outlet of the evaporator coil can be connected to or is connected to the second output of the intermediate container. In this manner the coolant used for the cooling and the coolant condensed in the intermediate container can be jointly supplied to the vehicle air-conditioning system and/or to the coolant supply and/or to the first separation stage and/or to the second coolant supply.

The intermediate container and/or the coolant supply and/or the evaporator coil and/or associated lines and/or associated valves are provided for or designed for a batch-wise filling and emptying of the intermediate container. This brings about, among other things, a greater process efficiency.

If the (first) outlet of the intermediate container provided for the gaseous phase is controllable and/or has an opening threshold pressure of 1.01 bars to 2 bars, preferably from 1.03 bars to 1.3 bars and especially preferably from 1.05 bars to 1.15 bars, no other device components, for example, a vacuum pump, are required for conducting the non-condensable gases out of the intermediate container. The outlet can be opened manually or automatically and remains open preferably until a threshold pressure has been reached.

The concept “one” and in all of its possible grammatical cases is regularly to be understood as “at least one”. If “exactly one” is meant, this will be expressly clarified. This also applies to all other piece numbers, so that, e.g., “four pieces” regularly denotes “at least four pieces” if not expressly limited. In the case of technical and scientific magnitudes (temperature, pressure, force, energy, current strength, substance amount, etc.) on the other hand, indications of number are regularly to be understood as an example of a range known in the area of application if not expressly deviated from.

The structural parts which were previously cited and those claimed and described and to be used according to the invention in the exemplary embodiments are not subject to any special exceptional conditions as regards their size, shape, material selection and technical design, so that the selection criteria known in the area of application can be used in an unlimited manner.

Other details, features and advantages of the subject matter of the invention result from the subclaims and from the following description and the associated drawings which show - by way of example - an exemplary embodiment of a service device for vehicle air-conditioning systems.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

The sole figure (figure 2) shows a section of a block wiring diagram of those components of an air-conditioning service device for vehicle air-conditioning systems which are selectively or preferably used for the purpose of the invention. Otherwise, the service device for vehicle air-conditioning systems can contain other components such as are used, among other things, in the following protective rights of the applicant: WO 2007/085480 A1, WO 2011/063961 A1, WO 2012/034695 A1, DE 102009/054436 A1, DE 202006/001374 U1, DE 202006/001376 U1, DE 202008/003123 U1.

In the block wiring diagram according to figure 2, a coolant supply 215 for reprocessed coolant can be seen at the bottom left. It concerns a pressure container with, e.g., a 16 litre capacity in which substantially pure coolant is located underneath a liquid level whereas gaseous cooling components in addition to the noncondensable gases such as air are also present in the gas chamber above the latter in an amount dependent on the temperature and the pressure. The coolant supply 215 can be weighed in its entirety, as is known but not specifically shown. A coolant liquefier 215A connected upstream from the coolant can be located directly on the wall of the coolant supply 215, as is known but not specifically shown and weighed at the same time, or, e.g., as is shown in the drawings, it can be Io- cated at a separate position. Prepared coolant, that is, coolant substantially freed of compressor oil and any additive in a separating stage 240 known from WO 2011/063961 A1 then passes (after compression by a compressor 212, separation from compressor oil of the compressor in an oil separator 212B and having given off a part of the compression heat in a heating coil 242C of the heat exchanger 242) via switchable valves 212D and 242D into the coolant liquefier 215A. In this the coolant, which is compressed, for example, to 15 bars, is condensed giving off heat in order to subsequently pass (in liquid form) via a non-return valve 215D and a multi-port valve 215F and an immersion tube which also functions as a standpipe 215E into the lower receiving area of the coolant supply 215.

During the filling of a vehicle air-conditioning system the liquid coolant passes from the coolant supply 215 via the standpipe 215E, the multi-port valve 215F and other switching valves, such as the valve RE of a valve switching block not shown in the drawings, in dosed form into the vehicle air-conditioning system.

If, (starting as a rule from the high-pressure service connection of the vehicle air-conditioning system), coolant/compressor oil mixture is transported with the aid of the compressor 212 into the separating stage 240 (optionally with interpositioning of a vacuum pump not shown in fig. 2), it passes (optionally after passing a coarse filter not shown in the drawings) into the heat exchanger 242, which serves as an oil separator. In this heat exchanger 242, not yet evaporated coolant components are evaporated by the heating coil 242C and supplied via a line 246A to a gas dryer 246. The coolant freed from liquid components in this manner subsequently passes into the compressor 212, which is protected by a compressor emergency valve 212A against overload. The compressor oil needed for the compressor 212 also passes into the coolant compressed, e.g., to 1 to 19 bars and is resupplied in the circuit via the oil separator 212B and a capillary tube 212C to the compressor 212 in the circuit. Old compressor oil from the vehicle air-conditioning system and any additives in liquid form accumulate in the heat exchanger 242 in its sump area and can pass via a switchable oil discharge valve 216A into an old oil container (not shown in the drawings). Any gaseous components collecting in the old oil container can be removed by suction from time to time by the vacuum pump, which is not shown, and resupplied to the separating stage 240. To this extent, the service device for vehicle air-conditioning systems is known, among other things, from WO 2011/063961 A1.

In order to be able to free to the extent possible the gas volume present in the coolant supply container 215 and which consists to a large part of noncondensable gases (NKG), in particular of air and a pressure- and temperature -dependent amount of gaseous coolant, from the non-condensable gases so that they can be given off to the “environment”, an intermediate container 225 with a holding capacity which is as a rule comparatively lower (e.g., about 2.2 Itr.) than the coolant supply 215 is provided. It can be constructed as a pressure tank. The non-condensed gases standing under pressure pass from the gas chamber of the supply container 215 upon the opening of an overflow valve 225A into intermediate container 225 whose inner chamber is at first approximately at ambient pressure or, preferably at a pressure level below ambient pressure, which can be generated by the compressor 212 as explained in the following. A connection line 225G running from the intermediate container 225 to the separating stage 240 is held closed by a switchable separating valve 225F so that when the overflow valve 225A is open, the non-condensed gases can flow over into the intermediate container 225 until a pressure compensation with the gas chamber of the supply container 215 has been substantially achieved. The overflow valve 225A can then be closed again.

In order to condense the coolant components in the intermediate container 225, its gas chamber is cooled to, e.g., -30° Celsius. To this end, coolant can be transferred from the coolant supply 215 via a switchable valve 215G into an evaporator coil 225B. The liquid coolant is expanded via the thermostatic expansion valve 220. The thermostatic expansion valve measures the temperature at the output of the evaporator coil 225B on the power connection 225H and ensures a slight overheating of the coolant. The coolant gases evaporated here can pass via a non-return valve 225H and the line 225G to the compressor 212 in order to be fed back into the liquid phase of the supply container 215 after compression via the liquefier 215A. The coolant condensed from the non-condensed gases in the intermediate container 225 form a liquid level inside the intermediate container 225. Substantially only not-yet condensable gases such as in particular air are located above this liquid level.

It is now possible in different ways to remove the liquid and gas volumes that are separately present from the intermediate container 225. A possibility here is to utilize an excess pressure forming in the gaseous phase relative to the ambient pressure and to discharge the gaseous phase via a switchable outlet valve 225C into the environment. A slight residual pressure of, e.g., 1.1 bars absolute in the gaseous phase of the intermediate container 225 should preferably not be dropped below in order to avoid to the extent possible an entrance of noncondensable gases from the outside into the gas chamber of the intermediate container 225. After the closing of the outlet valve 225C, there are then distinctly fewer condensable gases in the intermediate container 225 than previously.

It is possible to allow the condensed coolant to flow off downward from the intermediate container 225 in order to evaporate it subsequently in the line 225G and/or in the heat exchanger 242. It is also possible to allow the condensed coolant (not shown) to flow off from the lower end of the intermediate container 225 directly into the coolant supply 215. For this, intermediate container 225C must be at an appropriate height level. This overflowing can be started and terminated by a magnetic valve (not shown).

Alternatively, the coolant condensed in the intermediate container 225 can be directly evaporated in the intermediate container 225 after the discharging of the non-condensable gases. To this end, a heating element 225D on the surface of the otherwise preferably thermally insulated intermediate container 225 can be used. In this manner the coolant passes, in particular as wet vapor, via the lines 225G and the heat exchanger 242 into the compressor 212, as described above, into the coolant supply container 215.

LIST OF REFERENCE NUMBERS

Claims (10)

1. Serviceudstyr til vedligeholdelse af køretøjsklimaanlæg, især til udskiftning af en blanding af kølemiddel/kompressorolie, med et kølemiddelreservoir (215) og med et skilletrin (240), der forsyner kølemiddel reservoiret til adskillelse af kølemiddel og ikke-kondenserbare gasser fra kompressorolie, hvor serviceudstyret omfatter et yderligere skilletrin med en mellembeholder (225), der forsynes fra kølemiddelreservoiret (215), især med dettes gasfase, til adskillelse af kølemiddel fra ikke-kondenserbare gasser, kendetegnet ved, at mellembeholderen (225) indeholder midler til køling og dermed kondensation af kølemidlet.

2. Serviceudstyr ifølge krav 1, kendetegnet ved, at kølemiddel reservoiret (215) har en overliggende udgang (225A’) til en blanding af kølemiddel/ikke-kondenserbare gasser fra kølemiddel reservoiret (215), der via et fortrinsvis aflukkeligt rør (225E) er forbundet med en indgang (225E’) i mellembeholderen (225) til blandingen af kølemiddel/ikke-kondenserbare gasser fra kølemiddelreservoiret (215).

3. Serviceudstyr ifølge krav 1 eller 2, kendetegnet ved, at mellembeholderen (225) har en første, fortrinsvis i det øvre område af mellembeholderen (225) anbragt, afspærrelig udgang (225C’) for de ikke-kondenserbare gasser til omgivelserne og en anden, fortrinsvis i det nedre område af mellembeholderen (225) anbragt, afspærrelig udgang (225F’) til kølemidlet.

4. Serviceudstyr ifølge krav 3, kendetegnet ved, at den anden udgang (225F’) er forbundet eller kan forbindes til det første skilletrin (240) og/eller kølemiddelreservoiret (215) og/eller køretøjsklimaanlægget og/eller et andet kølemiddelreservoir.

5. Serviceudstyr ifølge et af kravene 1 til 4, kendetegnet ved, at mellembeholderen (225) omfatter en fordamperslange (225B), som har en indgang (220’) og en udgang (225H’), der kan forbindes med en udgang (215G’) fra kølemiddelreservoiret (215).

6. Serviceudstyr ifølge krav 5, kendetegnet ved, at fordamperslangens (225B) udgang (225H’) kan forbindes med en anden udgang (225F’) i mellembeholderen (225).

7. Serviceudstyr ifølge et af kravene 3 til 6, kendetegnet ved, at mellembeholderens (225) første udgang (225C’) kan reguleres og/eller viser en åbningstryktærskel på 1,01 bar til 2 bar, fortrinsvis 1,03 bar til 1,3 bar og særligt foretrukket 1,05 bar til 1,15 bar.

8. Fremgangsmåde til drift af et serviceudstyr til vedligeholdelse af et -køretøjsklimaanlæg, ved hvilken - en blanding af kølemiddel/ikke-kondenserbare gasser/kompressorolie i kørertøjsklimaanlægget ledes ind i serviceudstyret, navnlig i et serviceudstyr ifølge ét af kravene 1 til 7, - blandingens kompressorolie udskilles i et første skilletrin (240) i serviceudstyret, -den for kompressorolien befriede blanding af kølemiddel/ikke-kondenserbare gasser samles i et kølemiddel reservoir (215), - i det mindste en del af blandingen af kølemiddel/ikke-kondenserbare gasser ledes ud af kølemiddel reservoiret (215) ind i en mellembeholder (225), kendetegnet ved, at - det gasformige kølemiddel afkøles i mellembeholderen (225), fortrinsvis ved fordampning af flydende kølemiddel, indtil i det mindste en overvejende kondensation.

9. Fremgangsmåde ifølge krav 8, kendetegnet ved, at i det mindste en del af de ikke-kondenserbare gasser efter kondensation af kølemidlet i mellembeholderen (225) afgives ved overtryk til omgivelserne.

10. Fremgangsmåde ifølge krav 8 eller 9, kendetegnet ved, at det kondenserede kølemiddel i mellembeholderen (225) ledes af tyngdekraft og/eller overtryk ud af mellembeholderen (225) eller i det mindste fordampes delvis efter en forudgående bortledning af ikke-kondenserede gasser og fjernes efterfølgende under overtryk og/eller ved udsugning fra mellembeholderen.