SERVICING DEVICE FOR VEHICLE AIR-CONDITIONING SYSTEMS AND METHOD FOR OPERATING SAID DEVICE

Abstract

The invention relates to a servicing device for vehicle air-conditioning systems comprising an evacuation assembly for withdrawing the coolant/compressor oil mixture from the coolant circuit of a vehicle air-conditioning system and comprising a coolant gas analyzer. In said device, a gas analysis connection is provided on or in at least one of the connection lines between the servicing device and the vehicle air-conditioning system. Said gas analysis connection is fluidically connected or can be fluidically connected to the coolant gas analyzer via an oil separator that can be evacuated and that is connected at least at intervals to an evacuation assembly.

Description

FIELD OF THE INVENTION

The invention relates to a servicing device for vehicle air-conditioning systems with upstream refrigerant gas analysis having the features of the preamble of claim 1, and to a method for operating said device. Accordingly, a servicing device for vehicle air-conditioning systems comprises at least one emptying device for extracting the refrigerant/compressor oil mixture from the refrigerant circuit system of a vehicle air-conditioning system, and a refrigerant gas analyzer. As is known per se, at least one compressor oil separator, a refrigerant compressor, a separator stage, a refrigerant weighing device, a vacuum pump for emptying the residual contents of the refrigerant circuit system of the vehicle air-conditioning system and/or at least one pressure-controlled and/or time-controlled switchover valve block for optionally directly connecting the refrigerant circuit system of the vehicle air-conditioning system fluidically to the separator stage or to a refilling system for refilling the vehicle air-conditioning system with refrigerant, compressor oil and possibly additive can preferably also be provided.

TECHNOLOGICAL BACKGROUND

Servicing devices for vehicle air-conditioning systems serve, inter alia, within the context of maintenance, to empty the refrigerant circuit of a very wide variety of vehicle air-conditioning systems from time to time and to introduce a new refrigerant filling. It is necessary here to maintain precise quantities and refrigerant specifications. Moreover, in many cases lubricant for the compressor of the refrigerant circuit of the vehicle air-conditioning system has to be removed and as a rule refilled again. This also takes place in quantities and specifications which are dependent on the vehicle type and/or air-conditioning unit type. Moreover, some vehicle air-conditioning systems require an additive for the refrigerant circuit, which additive is likewise replaced at least partially during a maintenance service. The compressor oil usually passes into the refrigerant circuit and is therefore also circulated during operation of the vehicle air-conditioning systems. Only very specific pairings of refrigerant and compressor oil are compatible with one another for this purpose. In order for it to be possible, after the extraction of the refrigerant/compressor oil mixture, to recover at least part, preferably the predominant part, of the refrigerant for re-use, servicing units for vehicle air-conditioning systems usually also have a separator, by way of which refrigerant can be separated from the refrigerant/compressor oil mixture for re-use (compressor oil separator). Used compressor oil and, optionally, used additive is/are collected as a rule by the servicing device, in order to be discarded or reused later.

WO 2007/085480 from the applicant has disclosed a servicing device for vehicle air-conditioning systems in accordance with the block circuit diagram according to FIG. 1. With a solid line, said figure shows the essential constituent parts of a usual servicing device for a vehicle air-conditioning system and, with dashed lines, shows a vehicle air-conditioning system to be maintained. The latter comprises an oil-lubricated compressor 1′, a condenser 2′, an evaporator 3′, and pipelines 4A′-4C′ which produce a closed coolant system between said components. Furthermore, a dryer 5′ is provided which can also serve as collector or reservoir for refrigerant. Finally, two servicing connections 6A′/6B′ are installed into the refrigerant circuit for the exchange of fluid. The cold which is available at the evaporator 3′ is led away by a cold air fan 7′ and fed to the vehicle interior. The condensation heat of the condenser 2′ is transported away by a warm air fan 8′. Servicing connection connectors 9A′ and 9B′ allow refrigerant/compressor oil mixture to be drawn off or filled at the servicing connections 6A′, 6B′ in the case of maintenance. The vehicle air-conditioning system which is denoted overall by 10′ differs from vehicle type to vehicle type and is not the subject matter of the present invention.

The servicing device which is denoted overall by 20′ for a vehicle air-conditioning system has flexible pressure hoses 11A′, 11B′ for connecting the servicing unit 20′ to the vehicle air-conditioning system 10′ via the servicing connection connectors 9A′, 9B′ at the servicing connections 6A′, 6B′. An exhaust pump 12′ which is configured as a refrigerant compressor conveys used refrigerant/compressor oil mixture via the pressure hoses 11A′ and 11B′ and the separator 14′. The latter separates refrigerant from the extracted mixture by way of evaporation and feeds it to a refrigerant store 15′ which is configured as a pressure container. Compressor oil/additive mixture which is separated in the separator 14′ is collected in an exchangeable waste oil container 16′ and is weighed by means of a weighing device 17A′. An air-cooled refrigerant condenser 15A′ is connected fixedly to the refrigerant store 15′. Returned refrigerant is therefore fed predominantly in liquid form to the refrigerant store 15′. The entire refrigerant store including condenser rests on a further weighing device 17B′ for detecting the refrigerant which is fed in and is led away and also the available refrigerant. After the extraction of the used mixture, a vacuum pump 13′ provides the vacuum which is required for refilling in the circuit of the vehicle air-conditioning system and discharges the extracted gas volume to the atmosphere.

A refilling system which is denoted overall by 19′ comprises substantially exchangeable storage vessels 19D′ for compressor oil and 19C′ for additives, a control unit 19A′ with valve block and control lines 19B′, a remote indication 19E′ and metering and valve units 19F″ to 19F″″. The storage vessels 19C′ and 19D′ can preferably be weighed. Further weighing devices 17C′, 17D′ serve for this purpose.

DE 20 2008 003 123 U1 has disclosed a further servicing device for vehicle air-conditioning systems from the applicant, in which the refilling capability of the previously evacuated vehicle air-conditioning system is improved by a heat source, provided in the refrigerant storage vessel, for increasing the pressure of the refrigerant. A comparable servicing device for vehicle air-conditioning systems is known from US 2009/0158756A1.

In a further servicing device of the generic type for vehicle air-conditioning systems from the applicant, DE 2009 054 446 which is still unpublished and was filed on Nov. 25, 2009 has disclosed, in a first maintenance phase, to extract a circuit mixture of refrigerant, compressor oil and optionally further mixture constituent parts from a vehicle air-conditioning system into a separator stage by means of a refrigerant compressor via a separator and in the process to separate, compress and collect refrigerant by means of the separator from the extracted circuit mixture, and to determine its quantity. In a second maintenance phase, the refrigerant circuit system of the vehicle air-conditioning system has its remaining contents largely removed by means of a vacuum pump. Residual gases which are pumped out in the second maintenance phase are guided by means of the refrigerant compressor through the separator stage and the quantity of the remaining refrigerant which is collected in the process is determined. The diagnosis of the state of the vehicle air-conditioning system, inter alia, is improved by way of this measure.

In order to avoid a refrigerant which is, for example, used erroneously there from passing from a vehicle air-conditioning system to be maintained into the servicing device, which refrigerant is not compatible with the remaining refrigerant/refrigerants extracted by the servicing device and stored in it, gas analysis devices for refrigerant to be extracted have been used since relatively recently. One of the disadvantages comprises the fact that the accuracy of the analysis fluctuates as a rule and the analysis device therefore has to be tested frequently.

SUMMARY OF THE INVENTION

Proceeding from this, the invention is based on the object of improving the stability of the accuracy of the analysis in a servicing device for vehicle air-conditioning systems with upstream refrigerant gas analysis.

In order to solve the problem on which the invention is based, a servicing device of the generic type for vehicle air-conditioning systems having the features of claim 1 and a method having the features of claim 4 are proposed. Accordingly, a gas analysis connection is provided on or in at least one of the connecting lines between the servicing device and the vehicle air-conditioning system. Said gas analysis connection is connected or can be connected fluidically to the gas analyzer for refrigerant via an oil separator which can be evacuated and is connected at least temporarily to an evacuating device.

The invention proceeds from the finding that the presence of compressor oil in the refrigerant to be exchanged represents a substantial cause of malfunctions of the analysis device.

If the oil separator can be connected to a separator stage for refrigerant/compressor oil mixture, the sample of refrigerant/compressor oil mixture which is drawn from the vehicle air-conditioning system for the purpose of refrigerant gas analysis can be treated further in the same way as the refrigerant/compressor oil mixture which accumulates during emptying of the vehicle air-conditioning system and, in particular, refrigerant can be recovered.

If the region of the connecting lines between the oil separator and service connection connectors of the servicing device can be emptied of refrigerant/compressor oil mixture via connectors, the servicing device can be protected as a result in a simple way against refrigerants and/or compressor oils which are not accepted.

By way of the invention, the predominant part of the refrigerant/compressor oil mixture which is present for sample-taking for the gas analysis can be separated from compressor oil components in an integrated process with an extremely justifiable outlay. As a result, malfunctions of the gas analyzer and/or fluctuating analysis values are ruled out as far as possible, without it being necessary for complicated maintenance work to be carried out for this purpose. If required, a gas analysis means according to the invention can be retrofitted into an existing servicing device for vehicle air-conditioning systems, in particular as a module. A preliminary setup which is already provided for this purpose, for example in the form of suitable connection points, is helpful.

The abovementioned components and the claimed components which are described in the exemplary embodiments and are to be used according to the invention are not subject to any special exceptional conditions in terms of their size, shape, material selection and technical design, with the result that the selection criteria which are known in the field of use can be used in an unrestricted manner.

Further details, features and advantages of the subject matter of the invention result from the subclaims, and from the following description and the associated drawing, in which one exemplary embodiment of a servicing device for vehicle air-conditioning systems is shown by way of example. Individual features of the claims or the embodiments can also be combined with other features of other claims and embodiments.

BRIEF DESCRIPTION OF THE FIGURES

In the drawing:

FIG. 2 shows a servicing device for vehicle air-conditioning systems as a block circuit diagram, in a basic position,

FIG. 3 shows the same servicing device in the evacuating phase of an oil separator (156),

FIG. 4 shows the same servicing device in the filling phase of the oil separator (156),

FIG. 5 shows the same servicing device in the sample-taking phase of the analyzer (161),

FIG. 6 shows the same servicing device in the analysis phase of the analyzer (161),

FIG. 7 shows the same servicing device in the emptying phase of the oil separator (156), after approval of the analyzed refrigerant, and

FIG. 8 shows the same servicing device in the emptying phase of the oil separator (156), after rejection of the analyzed refrigerant.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

The basic construction of a servicing device of the generic type for vehicle air-conditioning systems results from the block circuit diagram according to FIG. 2, not all the components which are shown being necessary constituent parts of the present invention, however. Accordingly, servicing connection connectors 109A, 109B are provided for connection to the coolant/compressor oil circuit of a vehicle air-conditioning system (not shown here), in order to service the latter, in particular to empty it and refill it. There is a fluidic connection via pressure hoses 111A, 111B to a first switchover valve block 130, the function of which will be explained further below. The switchover valve block 130 is connected fluidically firstly to a separator stage 140 which is shown on the right in the figure and will be explained further below, and secondly (at the bottom left in the figure) to a vacuum unit 150 which will likewise be explained further below. A low pressure manometer 126A and a high pressure manometer 126B, connected to the switchover valve block 130, serve, inter alia, to check the state and function of the coolant/compressor oil circuit of the vehicle air-conditioning system. Furthermore, the switchover valve block 130 is connected fluidically to a refilling system 119 for compressor oil and additives, having weighing devices 117C and 117D for dispensers 119C, 119D, for example for an additive for leak search and for fresh oil, respectively. The system pressure within the switchover valve block 130, which is of significance for the system controller which will be explained further below after emptying has begun of the fluid circuit, is monitored via a pressure sensor 131A which is connected to a collecting line 130A of the switchover valve block 130, with the result that the system pressure, in particular the refrigerant pressure of the vehicle air-conditioning system is monitored, as a result of which, inter alia, the circuit systems which are explained in the following text (separator stage 140 and vacuum unit 150 and associated valve circuits) can be controlled.

The method of operation of the separator stage 140 is as follows: after connection of the servicing connection connectors 109A, 109B to the corresponding ports of the vehicle air-conditioning system and opening of the corresponding valves LP, HP, Z2 of the switchover valve block 130, the system pressure of the vehicle air-conditioning system is available, in order to transfer a first part of the contents of the refrigerant/compressor oil circuit of the vehicle air-conditioning system into the separator stage 140. Said system pressure is already approximately 3 bar absolute at 0° C. and is already in an order of magnitude of 6 bar absolute at approximately 20° C., with the result that, as in the filling phase according to FIG. 4, for example, the conveying of refrigerant/compressor oil mixture takes place. The initial emptying of the vehicle air-conditioning systems (not shown) toward the separator stage 140 can likewise first of all take place automatically. Otherwise, this conveying is assisted by operation of a compressor 112, as explained further below, and is later kept further in motion when the system pressure drops. From the switchover valve block 130, the refrigerant/compressor oil mixture passes via a coarse filter 114 and a constant pressure valve 141 which is set to approximately 3.5 bar absolute into a jacketed heat exchanger 142, to be precise into the inner container 142A thereof. There the volatile components are evaporated and the gas phase passes via a line 146A into a gas-drying apparatus 146 and from there into the compressor 112.

The jacketed heat exchanger 142 serves at the same time as a separator for liquid constituent parts of the refrigerant/compressor oil mixture; these are essentially the compressor oil, any additives which are contained and residual quantities of the refrigerant which are still bound in the compressor oil. This liquid phase is fed via an oil discharge valve 116A to a waste oil container 116. The quantities which accumulate can be registered via a weighing device 117A which also weighs the container.

The compressor 112 ensures that, at its output side, the refrigerant is compressed to a pressure of up to, for example, 19 bar absolute. A compressor emergency shut-off valve 112A limits the pressure as a rule to 19 bar. Since the lubricating oil of the compressor 112 also passes into the compressed refrigerant, it is separated in a (first) oil separator 112B and is fed via a capillary tube 112C which acts like a pressure throttle to the lubrication means of the compressor 112 again. Via a solenoid valve 112D, the compressed, dried refrigerant which is freed from compressor oil and additives passes into a heating coil 142C which is situated in the gas space of the inner container 142A of the jacketed heat exchanger 142. As a result, the heat of compression which is contained in the compressed refrigerant can be dissipated, in order to evaporate the refrigerant/compressor oil mixture which arrives freshly from the vehicle air-conditioning system as far as possible on the cold side. From the heating coil 142C, the purified (recycled) refrigerant passes first of all into the outer jacket region (outer container 142B) of the jacketed heat exchanger 142 and from there via a valve block 142D and a connecting hose 129 to the refrigerant store 115 (storage vessel).

The storage vessel including contents is weighed by a weighing device 117B. The storage vessel also carries a refrigerant condenser 115A which is also advantageously weighed and in which the refrigerant which is under compression pressure is condensed, in order to pass in liquid form into the refrigerant store 115. Both the (first) separator 112B and the refrigerant store 115 are designed as what are known as pressure vessels. The pressure in the refrigerant store 115 is secured against overpressure via a valve 115B because the gas phase, which forms above the liquid level, of gases which cannot be condensed has to be discharged in a regulated manner for safety reasons above a defined overpressure of, for example, 16 bar. This can also take place in a non-automatic manner via a handle 115C by an operator.

The liquid refrigerant passes via a nonreturn valve 115D and a riser pipe 115E into the liquid region of the refrigerant store 115. In order for it to be possible to refill the vehicle air-conditioning system with refrigerant, liquid refrigerant passes via the riser pipe 115E, a valve 115F and a connecting line 115G back into the switchover valve block 130, preferably into its collecting line.

As soon as the vehicle air-conditioning system is emptied to such an extent that the compressor 112 can no longer suck in sufficient refrigerant/compressor oil mixture on its low pressure side, which can be the case, for example, at a pressure of 0.7 bar absolute, the vacuum unit 150 is started, optionally by actuation of the corresponding valves. Further gas constituent parts are thus sucked out of the fluid circuit of the vehicle air-conditioning system by the collecting line of the switchover valve block 130 by the vacuum pump 113. From the outlet side of the vacuum pump 113, this gas or gas mixture passes via a (second) switchover valve block 151 and solenoid valves AU into the connecting line 143 which couples the switchover valve block 130 fluidically to the separator stage 140. The gas quantities which are conveyed by the vacuum pump 113 from the vehicle air-conditioning system are then treated in the separator stage 140 in exactly the same way including weighing as the quantities of refrigerant/compressor oil mixture which exit the vehicle air-conditioning system automatically at the beginning of the emptying process. The difference from the first phase, called outflow phase here, consists in the fact that no liquid constituent parts are sucked out of the vehicle air-conditioning system on account of the preceding outflow phase which is assisted by the compressor 112, that is to say that substantially only gaseous refrigerant or optionally air is still sucked out of the vehicle air-conditioning system. Relatively large gas quantities are to be dealt with first of all here. Toward the end of the second phase, called the evacuating phase here, the gas quantities become considerably smaller, however. At an inlet pressure of approximately 1 mbar or after a process time which has been preset fixedly has elapsed, the evacuating process is ended.

The gas pressure which is generated by the vacuum pump 113 on its outlet side should not exceed an order of magnitude of 2 bar absolute, in order not to damage the vacuum pump 113. For pressure checking, the switchover valve block 151 which is connected downstream of the vacuum pump is assigned a pressure switch 151A, with the aid of which the vacuum pump 113 switches off if an outlet pressure of, for example, 2 bar is exceeded, until the outlet pressure has again dropped correspondingly, with the result that the vacuum pump 113 can be switched on again.

Since the servicing device can be used not only for extracting and refilling the vehicle air-conditioning system in normal maintenance operation, but rather can also be used for cases of repair to air-conditioning systems, for example the exchange of components, the switchover valve block 151 which is connected downstream of the vacuum pump 113 is equipped with a discharge valve VO which can lead, for example, into the atmosphere. If merely air is therefore sucked out of the repaired vehicle air-conditioning system for subsequent refilling, this does not necessarily have to pass into the separator stage 140.

At or close to its upper end, a (second) oil separator 156 which can be evacuated is connected fluidically to the low-pressure side via a connecting line 157A which can be shut off and, for example, a shut-off valve 156A and (not shown) optionally 156B which can be actuated automatically or is operated by hand, in a first (shown) embodiment, close to or, in the exemplary embodiment, on the inlet side of the first switchover valve block 130.

At or close to its lower end, the oil separator 156 can be connected fluidically to the suction side of the vacuum pump 113 via at least one further shut-off valve 156C and (not shown) optionally 156D and a connecting line 157B, and further via the first switchover valve block 130 and its collecting line 130A. A direct flow connection can therefore be produced between the oil separator 156 which can be evacuated and the vacuum pump 113. The connecting line 157B preferably also has a flow connection to the waste oil container 116, in particular at a line region 157C which is inclined downward, with the result that compressor oil which accumulates in the second oil separator 156 can also be received directly by the waste oil container 116.

The method of operation is as follows: at the beginning of a refrigerant exchange, the servicing connection connectors 109A, 109B are coupled fluidically to the corresponding coupling points of the refrigerant circuit of a vehicle air-conditioning system. An evacuating routine for the (second) oil separator 156 is then carried out, as can be seen in bold lines from FIG. 3. To this end, the shut-off valves 156A and 161B are closed, optionally automatically, and the shut-off valve 156C is kept open or is opened, preferably electrically. Shut-off valves 156A and optionally 156B (not shown) upstream of the oil separator 156 and/or shut-off valves 156C and optionally 156D downstream of the oil separator 156 can (in principle) be replaced by a single shut-off valve (156A or 156C), as shown. In the above-described way, the oil separator 156 can be evacuated and its internal pressure can be reduced to, for example, 1 mbar absolute. The short lines upstream of the oil separator 156 toward said shut-off valve/valves are likewise evacuated, with the result that there are no gases which distort the later analysis, above all in the oil separator 156. Any residues of compressor oil are transferred out of the oil separator 156 into the waste oil container 116.

In the following work step, the sample provision, as indicated by the bold lines in FIG. 4, the oil separator 156 is shielded toward the vacuum pump 113 by closure of the shut-off valve 156C, and is connected fluidically via the connecting line 157A to the gas analysis connection 161A and the low pressure line, such as the pressure hose 111A, by opening of the shut-off valve 156A. The oil separator 156 is therefore also connected in a fluidically conducting manner to the servicing connection connector 109A of the low pressure side and the vehicle air-conditioning system which is connected upstream. As a result of the positive pressure which prevails as a rule in the vehicle air-conditioning system at the beginning, but at any rate on account of the vacuum in the oil separator 156, refrigerant/compressor oil mixture then flows over into the oil separator 156 until its internal pressure is equalized with that of the vehicle air-conditioning system, or until the shut-off valve 156A is closed again. At any rate, it is awaited as a rule until a certain positive pressure prevails in the oil separator 156. The liquid phase of the refrigerant/compressor oil mixture settles in the bottom region at the lower end of the oil separator 156 as early as during the flow of used refrigerant/compressor oil mixture over into the oil separator 156 and also after closure of its shut-off valve 156A which is situated upstream, whereas evaporated refrigerant and possibly air are situated in the gas phase which is formed above said liquid level. The degree of separation is preferably 99% or better, but should at least lie above 90%.

In the next work phase, as shown in FIG. 5 by bold lines, the oil separator 156 is connected fluidically to the gas analyzer 161 by opening of the inlet-side shut-off valve 161B. As a result of the positive pressure which prevails in the gas phase of the oil separator as a rule, refrigerant gas and possibly air, but no compressor oil, then flows over into the gas analyzer 151. The gas analyzer 161 can have a dedicated pump (not shown) which is known per se, in order to suck sample gas into the gas analyzer. The gas analysis is carried out (FIG. 6) as early as during the flow over of the sample gas or else, as preferred, after fluidic separation of the oil separator 156 from the gas analyzer 161 by closure of the shut-off valve 161B, and the tested refrigerant sample is subsequently discharged from the analyzer.

If the gas analyzer 161 accepts the refrigerant gas, the refrigerant which is present in the oil separator 156 and the compressor oil can then be extracted, as shown by way of bold lines in FIG. 7, by the shut-off valve 156C being opened again. However, the mixture which is extracted in the process is preferably not discharged into the atmosphere, but rather is fed by the vacuum pump 113 via the second valve block 151 and a connecting line 143 to the jacketed heat exchanger 142, in order to separate the compressor oil into the waste oil container 116 and to recover the refrigerant in the same way as takes place during the step of emptying the vehicle air-conditioning system. Here, as has already been mentioned further above in conjunction with FIG. 2, the compressor oil can also be received directly by the waste oil container 116 via the connecting line 157B and a flow connection to the waste oil container 116, in particular at a line region 157C which is inclined downward. Otherwise, the refrigerant/compressor oil mixture passes via the first valve block 130 into the separator stage 140 and is treated there, as has already been explained in greater detail in conjunction with FIG. 2.

If, in contrast, the gas analyzer 161 does not accept the refrigerant sample which was obtained from the vehicle air-conditioning system, the refrigerant/compressor oil mixture must not flow, or must not flow further, from the vehicle air-conditioning system into the servicing device 100. In this case, as shown by way of bold lines in FIG. 8, the refrigerant/compressor oil mixture is returned via the connecting line 157A and the gas analysis connection 161A and is discharged via connectors 162A, 162B on the pressure hoses 111A, 111B or their end-side connections from the vehicle air-conditioning system and the oil separator 156 to a further reclamation means, and also does not pass, or does not pass further, into the switchover valve block 130.

LIST OF DESIGNATIONS

• • 1′ Compressor
  • 2′ Condenser
  • 3′ Evaporator
  • 4A′-C′ Pipelines
  • 5′ Separator
  • 6A′/B′ Servicing connections
  • 7′ Cold air fan
  • 8′ Warm air fan
  • 9A′/B′ Servicing connection connectors
  • 10′ Vehicle air-conditioning system
  • 11A′/B′ Pressure hoses
  • 12′ Exhaust pump
  • 13′ Vacuum pump
  • 14′ Separator
  • 15′ Refrigerant store
  • 15A′ Refrigerant condenser
  • 16′ Waste oil container
  • 17A′-J′ Weighing devices
  • 18′ Relief device
  • 19′ Refilling system
  • 19A′ Control unit with valve block
  • 19B′ Control lines
  • 19C′ Storage vessel
  • 19D′ Storage vessel
  • 19E′ Remote indication
  • 19F″ Metering and valve unit
  • 19F″′ Metering and valve unit
  • 19F″′ Metering and valve unit
  • 20′ Servicing device
  • 26A′ Low pressure manometer
  • 26B′ High pressure manometer
  • 100 Servicing device
  • 109A Servicing connection connector
  • 109B Servicing connection connector

111A Pressure hoses

• • 111B Pressure hoses
  • 112 Compressor
  • 112A Compressor emergency shut-off valve
  • 112B (First) oil separator
  • 112C Capillary tube
  • 112D Solenoid valve
  • 113 Vacuum pump
  • 114 Coarse filter
  • 115 Refrigerant store
  • 115A Refrigerant condenser
  • 115B Valve
  • 115C Handle
  • 115D Nonreturn valve
  • 115E Riser pipe
  • 115F Valve
  • 115G Connecting line
  • 116 Waste oil container
  • 116A Oil discharge valve
  • 117A Weighing device
  • 117B Weighing device
  • 117C Weighing device
  • 117D Weighing device
  • 119 Refilling system
  • 119C Dispenser
  • 119D Dispenser
  • 126A Low pressure manometer
  • 126B High pressure manometer
  • 129 Connecting hose
  • 130 First switchover valve block
  • 130A Collecting line
  • 131A Pressure sensor
  • 140 Separator stage
  • 141 Constant pressure valve
  • 142 Jacketed heat exchanger
  • 142A Inner container
  • 142B Outer container
  • 142C Heating coil
  • 142D Valve block
  • 143 Connecting line
  • 146 Gas drying apparatus
  • 146A Line
  • 150 Vacuum unit
  • 151 Second switchover valve block
  • 151A Pressure switch
  • 152A Pressure reducer
  • 152B Pressure reducer
  • 153 Flushing medium tank
  • 154 Filter
  • 155 Inspection window
  • 156 (Second) oil separator
  • 156A,C Shut-off valves
  • 157A Connecting line
  • 157B Connecting line
  • 157C Line region
  • 158 Shut-off valve
  • 159 Coupler
  • 160 Evacuating line
  • 161 Gas analyzer
  • 161A Gas analysis connection
  • 161B Shut-off valve
  • 162A/B Connector

Claims

1. A servicing device for vehicle air-conditioning systems comprising an emptying device for extracting the refrigerant/compressor oil mixture from the refrigerant circuit system of a vehicle air-conditioning system, and a refrigerant gas analyzer, characterized in that a gas analysis connection is provided on or in at least one of the connecting lines between the servicing device and the vehicle air-conditioning system, which gas analysis connection) is connected or can be connected fluidically to the gas analyzer for refrigerant via an oil separator which can be evacuated and is connected at least temporarily to an evacuating device.

2. The servicing device as claimed in claim 1, characterized in that the oil separator can be connected or is temporarily connected fluidically to a separator stage for refrigerant/compressor oil mixture.

3. The servicing device as claimed in claim 1, characterized in that the region of the connecting lines between the oil separator and servicing connection connectors can be emptied of refrigerant/compressor oil mixture via connectors

4. A method for the upstream refrigerant gas analysis in servicing devices for vehicle air-conditioning systems, characterized in that a sample of refrigerant/compressor oil mixture from the vehicle air-conditioning system is transferred from the vehicle air-conditioning system into a previously evacuated oil separator and, after the connecting line to the vehicle air-conditioning system is closed again and, after a separation into a gas phase and a liquid phase which is carried out in the oil separator, the gas phase region is connected to the gas analyzer for refrigerant analysis.

5. The method as claimed in claim 6, characterized in that the oil separator which is connected upstream of the gas analyzer is connected to a separator stage for refrigerant/compressor oil mixture which comes from the vehicle air-conditioning system, with the result that the sample volume, drawn for the purpose of gas analysis, of refrigerant/compressor oil mixture from the vehicle air-conditioning system is treated further.

6. The method as claimed in claim 4, characterized in that refrigerant/compressor oil mixture which is not accepted by the gas analyzer is discharged separately from the oil separator and the connecting lines to the vehicle air-conditioning system and from the vehicle air-conditioning system, without coming into contact with the remaining lines and containers which are present in the servicing device for refrigerant and/or compressor oil.

7. The servicing device as claimed in claim 2, characterized in that the region of the connecting lines between the oil separator and servicing connection connectors of the servicing device can be emptied of refrigerant/compressor oil mixture via connectors.

8. The method as claimed in claim 5, characterized in that refrigerant/compressor oil mixture which is not accepted by the gas analyzer is discharged separately from the oil separator and the connecting lines to the vehicle air-conditioning system and from the vehicle air-conditioning system, without coming into contact with the remaining lines and containers which are present in the servicing device for refrigerant and/or compressor oil.