Patent Description:
Vehicle air conditioning systems, particularly air conditioning systems of recreational vehicles, need to be serviced in regular intervals. During servicing, the refrigerant used in the refrigerant circuit of the vehicle air conditioning system is exchanged. That is, used refrigerant is replaced by fresh refrigerant. For this purpose, service units for vehicle air conditioning systems are known with which the exchange of the refrigerant can be performed. These service units regularly comprise pumps for draining used refrigerant from the refrigerant circuit and for refilling the refrigerant circuit with fresh refrigerant.

In order to ensure that no moisture or other contaminants remain in the refrigerant circuit, which would deteriorate the cooling performance and longevity of the vehicle air conditioning system, these service units additionally comprise a vacuum pump for evacuating the refrigerant circuit before refilling it with fresh refrigerant. Due to their design, these vacuum pumps require vacuum pump oil for lubrication of the moving parts of the vacuum pump and for sealing against atmospheric pressure. In order to maintain the desired vacuum performance of the vacuum pump, the vacuum pump oil has to be exchanged on a regular basis, as well.

For the vacuum pump to function correctly, is important that the correct amount of the correct type of vacuum pump oil is used when refilling the vacuum pump oil. Up to now, the vacuum pump oil is provided in standard oil containers and the user servicing the vacuum pump has to measure the correct amount of vacuum pump oil which needs to be refilled into the vacuum pump or check an inspection glass of the vacuum pump to ensure that the correct amount of vacuum pump oil is refilled. Depending on the vacuum pump of the service unit, different amounts of different types of vacuum pump oil are necessary, however. Especially in service centers which service different kinds of recreational vehicles for their customers, multiple service units for the different kinds of air conditioning units have to be available. These different service units may use different vacuum pumps which require different amounts of different types of vacuum pump oil. Thus, it is obvious that errors regarding the correct type or the correct amount of vacuum pump oil can occur when servicing the vacuum pumps of different service units.

Furthermore, in known service units, the vacuum pump is located within a housing of the service unit. To service the vacuum pump, that is, to exchange the vacuum pump oil, the housing of the service unit has to be opened, the used vacuum pump oil has to be drained from the vacuum pump and fresh vacuum pump oil has to be refilled into the vacuum pump using a funnel. Afterwards, the housing has to be closed again. This procedure is rather time consuming.

<CIT> discloses a service unit for an air conditioning system comprising a housing, a vacuum pump and a connection element configured to be connected to an oil container; a ventilation element is configured to be connected to the connection element.

Additionally, with the refrigerants used in vehicle air conditioning systems, it is important that the interior of the service unit is properly ventilated so that refrigerant gases which might leak during use of the service unit can evaporate. Improperly closing the housing of the service unit after servicing the vacuum pump is, therefore, another potential source of error.

In light of the above, it is an object of the present invention to provide a possibility for servicing a vacuum pump of a service unit for a vehicle air conditioning system in a quicker and more reliable manner.

This object is achieved with a vacuum pump servicing adapter according to claim <NUM>.

The vacuum pump servicing adapter for servicing a vacuum pump of a service unit for a vehicle air conditioning system according to the present invention comprises a connection element and a ventilation element. The connection element is configured to be connected to an oil container and the ventilation element is configured to be connected to the connection element in a storage orientation and in a ventilation orientation.

The ventilation element is a component which is separate from the connection element and which can be connected to the connection element in two different orientations. The connection between the ventilation element and the connection element as well as between the oil container and the connection element can be realized in multiple different manners such as via a screw connection or a plug-on connection. It is important, that the respective connection is a reversible connection. The connection between the ventilation element and the connection element in the ventilation orientation can be different than in the storage orientation. In particular, the ventilation element is connected to the connection element in the ventilation orientation via a screw connection. In particular, the ventilation element is connected to the connection element in the storage orientation via a plug-on connection. In particular, the connection element is connected to the oil container via a screw connection.

The vacuum pump servicing adapter according to the invention facilitates draining and refilling of vacuum pump oil from and into the vacuum pump of a service unit for a vehicle air conditioning system. Thus, servicing of the vacuum pump is achieved in a quicker and more reliable manner.

Preferably, the connection element comprises a first ventilation port, a second ventilation port, a ventilation line connecting the first ventilation port and the second ventilation port, a ventilation valve arranged in the ventilation line, a first oil port, a second oil port, an oil line connecting the first oil port and the second oil port, and an oil valve arranged in the oil line. In particular, the connection element comprises a connection element body in which the first ventilation port, the second ventilation port, the ventilation line, the ventilation valve, the first oil port, the second oil port, the oil line and the oil valve are provided. In particular, the first ventilation port comprises an opening in a side wall of the connection element body. In particular, the connection element body comprises an internal thread for connecting the ventilation element in the ventilation orientation and the oil container to the connection element. In particular, the ventilation element comprises an external thread for connecting the ventilation element to the connection element in the ventilation orientation. It is obvious to the skilled person that the ventilation element can comprise an internal thread and the connection element can comprise an external thread for connecting the two components. By providing the ventilation valve and the oil valve, the connection between the first ventilation port and the second ventilation port as well as the connection between the first oil port and the second oil port can be selectively opened and closed. This results in a controlled exchange of oil and a controlled ventilation.

Preferably, the ventilation valve is a check valve. Preferably, the oil valve is a check valve. In particular the ventilation valve is a spring-loaded check valve. In particular, the oil valve is a spring-loaded check valve. By providing check valves, in particular spring-loaded check valves, as the ventilation valve and the oil valve, the connection between the first ventilation port and the second ventilation port as well as the connection between the first oil port and the second oil port can be selectively opened and closed in a particularly reliable manner.

Preferably, the ventilation valve is opened by the ventilation element when the ventilation element is connected to the connection element in the ventilation orientation. In particular, the first ventilation port is open to the surroundings when the ventilation element is connected to the connection element in the ventilation orientation and the second ventilation port is connected to the surroundings via the ventilation line, the open ventilation valve and the first ventilation port. Thus, ventilation with the surroundings is possible when the ventilation element is connected to the connection element in the ventilation orientation.

Preferably, the ventilation valve is closed when the ventilation element is connected to the connection element in the storage orientation. In particular, a portion of the ventilation element covers the first ventilation port when the ventilation element is connected to the connection element in the storage orientation. Thus, the second ventilation port is not connected to the surroundings when the ventilation element is connected to the connection element in the storage orientation. Additionally, the first connection port is shielded from the surroundings by the ventilation element. This ensures that no contamination can enter into the connection element when the ventilation element is connected to the connection element in the storage orientation.

Preferably, the oil valve is opened by the oil container when the oil container is connected to the connection element. In particular, the oil valve and the ventilation valve are opened by the oil container when the oil container is connected to the connection element. Alternatively, the ventilation valve may be opened by the ventilation element when the ventilation element and the oil container are connected to the connection element. In particular, the oil container is connected to the first oil port and the second oil port is connected to the oil container via the oil line, the open oil valve and the first oil port when the oil container is connected to the connection element. In particular, the first ventilation port is open to the surroundings and the second ventilation port is connected to the surroundings via the ventilation line, the ventilation valve and the first ventilation port when the oil container is connected to the connection element. Thus, vacuum pump oil from the oil container is provided at the second oil port and ventilation with the surroundings is provided at the second ventilation port when the oil container is connected to the connection element.

Preferably, the vacuum pump servicing adapter further comprises a protection cap configured to be connected to the ventilation element when the ventilation element is connected to the connection element in the storage orientation. In particular, the protection cap comprises an internal thread for screwing onto an external thread of the ventilation element. The vacuum pump servicing adapter is in a storage state when the ventilation element is connected to the connection element in the storage orientation and the protection cap is connected to the ventilation element. With the protection cap, protection of the vacuum pump servicing adapter against contamination from the outside is increased when the vacuum pump servicing adapter is in the storage state.

Furthermore, the object of the invention is achieved with a service unit according to claim <NUM>. The service unit for a vehicle air conditioning system according to the invention comprises a housing, a vacuum pump and a vacuum pump servicing adapter as described above. The vacuum pump comprises a pump unit and an oil reservoir, wherein the oil reservoir comprises an oil drain.

With the service unit according to the present invention, the vacuum pump of the service unit can be serviced in a quicker and more reliable manner due to the vacuum pump servicing adapter.

Preferably, the service unit further comprises an oil pipe and a ventilation pipe and the oil reservoir further comprises an oil inlet and a ventilation connection. The vacuum pump servicing adapter is located outside the housing. The oil pipe is connected to the oil inlet and the vacuum pump servicing adapter and the ventilation pipe is connected to the ventilation connection and the vacuum pump servicing adapter. In particular, a first end of the oil pipe is connected to the oil inlet and a second end of the oil pipe is connected to the second oil port of the connection element of the vacuum pump servicing adapter. In particular, a first end of the ventilation pipe is connected to the ventilation connection and a second end of the ventilation pipe is connected to the second ventilation port of the vacuum pump servicing adapter. Thus, the vacuum pump can be serviced via the vacuum pump servicing adapter.

Preferably, the oil drain is accessible from outside the housing. Thus, the housing does not have to be opened to drain used vacuum pump oil from the oil reservoir of the vacuum pump.

Preferably, the vacuum pump is located inside the housing. Preferably, the vacuum pump further comprises an inspection glass visible from outside the housing. In particular, the vacuum pump oil level in the oil reservoir is visible through the inspection glass. Thus, the vacuum pump is securely located inside the housing. With the inspection glass visible from outside the housing, it is possible to check the level of the vacuum pump oil within the oil reservoir without opening the housing of the service unit which makes servicing the vacuum pump even more reliable.

Furthermore, the object is achieved with a method according to claim <NUM>. The method for servicing a vacuum pump of a service unit as described above comprises the steps of draining used vacuum pump oil from the oil reservoir of the vacuum pump and refilling the oil reservoir of the vacuum pump with fresh vacuum pump oil.

Preferably, the step of draining used vacuum pump oil comprises the steps of connecting the ventilation element of the vacuum pump servicing adapter to the connection element of the vacuum pump servicing adapter in the ventilation orientation, opening the oil drain of the oil reservoir, and closing the oil drain of the oil reservoir. In particular, the step of draining used vacuum pump oil additionally comprises the step of waiting until the entire used vacuum pump oil has been drained from the oil reservoir before closing the oil drain again. By connecting the ventilation element to the connection element in the ventilation orientation, the oil reservoir of the vacuum pump is connected to the surroundings via the ventilation connection, the ventilation pipe, the second ventilation port, the open ventilation valve and the first ventilation port. Thus, air can flow into the oil reservoir from the surroundings and the used oil can easily flow out of the oil drain of the oil reservoir when the oil drain is opened. Thus, the oil reservoir of the vacuum pump can be drained without opening the housing of the service unit.

Preferably, the step of draining used vacuum pump oil further comprises the step of removing the ventilation element from the connection element. Thus, the connection element is ready to be connected to an oil container. It is, however, also conceivable that the ventilation element stays connected to the connection element in the ventilation orientation and that the connection element is ready to be connected to an oil container, anyway.

Preferably, the step of refilling the oil reservoir comprises the steps of connecting a pressurized oil container to the connection element and removing the pressurized oil container from the connection element. In particular, the pressurized oil container is a two-chamber oil container comprising a rigid pressure chamber and a flexible oil chamber, wherein the pressure in the rigid pressure chamber causes the vacuum pump oil in the flexible oil chamber to exit the pressurized oil container once the pressurized oil container is connected to the connection element. Thus, the vacuum pump oil is provided to the oil reservoir via the vacuum pump servicing adapter automatically due to the pressure in the pressurized oil container. It is, however, also conceivable to additionally provide a vacuum oil pump to the service unit to suck fresh vacuum pump oil from an unpressurized oil container via the vacuum pump servicing adapter.

Preferably, the pressurized oil container contains the correct amount of vacuum pump oil necessary for refilling the oil reservoir of the vacuum pump. In particular, the pressurized oil container contains <NUM> or <NUM> of fresh vacuum pump oil. In particular, the step of refilling the oil reservoir comprises the step of waiting until the pressurized oil container is entirely empty before removing the pressurized oil container. Thus, it is not necessary to measure or check the correct amount of fresh vacuum pump oil refilled into the oil reservoir. Therefore, reliability of the servicing of the vacuum pump is further increased.

Preferably, the method further comprises the step of putting the vacuum pump servicing adapter into a storage state. In particular, the step of putting the vacuum pump servicing adapter into a storage state comprises the steps of connecting the ventilation element to the connection element in the storage orientation and connecting the protection cap to the ventilation element. However, the step of connecting the protection cap to the ventilation element can be omitted, if necessary and/ or desired. By putting the vacuum pump servicing adapter into the storage state, the vacuum pump servicing adapter is sufficiently protected from contamination from the outside when it is not used for servicing the vacuum pump.

In the following, an embodiment of the present invention is described with reference to the accompanying schematic figures, wherein:.

In <FIG>, a service unit <NUM> for a vehicle air conditioning system of a recreational vehicle is shown. The service unit <NUM> comprises a housing <NUM>, a vacuum pump <NUM> and a vacuum pump servicing adapter <NUM> which will be described in detail below. The vacuum pump <NUM> comprises a pump unit (not shown) and an oil reservoir <NUM>. The oil reservoir <NUM> comprises an oil drain <NUM>. The service unit <NUM> further comprises an oil pipe <NUM> and a ventilation pipe <NUM>. The oil reservoir <NUM> further comprises an oil inlet <NUM> and a ventilation connection <NUM>. A first end of the oil pipe <NUM> is connected to the oil inlet <NUM> of the vacuum pump <NUM> and a second end of the oil pipe <NUM> is connected to the vacuum pump servicing adapter <NUM>. A first end of the ventilation pipe <NUM> is connected to the ventilation connection <NUM> of the vacuum pump <NUM> and a second end of the ventilation pipe <NUM> is connected to the vacuum pump servicing adapter <NUM>.

The oil drain <NUM> is accessible from outside the housing <NUM>. In the present embodiment, the oil drain <NUM> is accessible from below the housing <NUM> as can be seen in <FIG>. The oil drain <NUM> has a closing element such as an oil drain plug or an oil drain screw for opening the oil drain <NUM> and draining used vacuum pump oil from the oil reservoir <NUM>.

In <FIG>, some elements such as the vacuum pump <NUM>, the oil pipe <NUM> and the ventilation pipe <NUM> are illustrated enlarged to facilitate understanding of the present invention. However, the vacuum pump <NUM> and the longest portions of the oil pipe <NUM> and the ventilation pipe <NUM> are located inside the housing <NUM>. The oil reservoir <NUM> of the vacuum pump <NUM> further comprises an inspection glass <NUM> which is visible from outside the housing <NUM>. For the inspection glass <NUM> to be visible from outside the housing <NUM>, the housing <NUM> comprises an opening or another inspection glass. Through the inspection glass <NUM>, the oil level in the oil reservoir <NUM> is visible.

A pressurized oil container <NUM> is illustrated in <FIG> which is connected to the vacuum pump servicing adapter <NUM>. The pressurized oil container <NUM> is a two-chamber oil container comprising a rigid pressure chamber <NUM> and a flexible oil chamber <NUM>. The flexible oil chamber <NUM> is located inside the rigid pressure chamber <NUM>, as can be seen in <FIG>. The pressure in the rigid pressure chamber <NUM> is used to push the oil contained in the flexible oil chamber <NUM> out of the pressurized oil container <NUM> once a valve closing the flexible oil chamber <NUM> is opened.

With respect to <FIG>, the vacuum pump servicing adapter <NUM> will now be described in detail. The vacuum pump servicing adapter <NUM> for servicing the vacuum pump <NUM> of the service unit <NUM> comprises a connection element <NUM> and a ventilation element <NUM> (see <FIG>). The connection element <NUM> is configured to be connected to the pressurized oil container <NUM> and the ventilation element <NUM> is configured to be connected to the connection element <NUM> in a storage orientation (see <FIG>) and in a ventilation orientation (see <FIG>). In comparison to <FIG> and <FIG> discussed below, the connection element <NUM> is illustrated upside down in <FIG>.

As can be seen in <FIG>, for example, the connection element <NUM> comprises a connection element body <NUM> in which a first ventilation port <NUM>, a second ventilation port <NUM>, a ventilation line <NUM> connecting the first ventilation port <NUM> and the second ventilation port <NUM>, a ventilation valve (not shown) arranged in the ventilation line <NUM>, a first oil port <NUM>, a second oil port <NUM>, an oil line <NUM> connecting the first oil port <NUM> and the second oil port <NUM> and an oil valve (not shown) arranged in the oil line <NUM> are arranged. The first ventilation port <NUM> is an opening in a side wall of the connection element body <NUM>. As seen in <FIG>, the ventilation line <NUM> is a channel in the connection element body <NUM> having a rectangular path and the oil line <NUM> is a channel in the connection element body <NUM> having a straight path.

The ventilation valve and the oil valve are spring-loaded check valves screwed into the ventilation line <NUM> and into the oil line <NUM>, respectively. For that purpose, the connection element <NUM> comprises a first internal thread <NUM> in the ventilation line <NUM> and a second internal thread <NUM> in the oil line <NUM>. The ventilation valve is screwed into the first internal thread <NUM> and the oil valve is screwed into the second internal thread <NUM>. Thus, the ventilation valve is arranged in the ventilation line <NUM> and the oil valve is arranged in the oil line <NUM>.

The connection element <NUM> further comprises a third internal thread <NUM> for connection with the ventilation element <NUM> and the pressurized oil container <NUM>. The recess in which the third internal thread <NUM> is arranged has an opening <NUM> towards the ventilation line <NUM> so that the ventilation valve can be screwed into the first internal thread <NUM> in the ventilation line <NUM>.

When the ventilation element <NUM> is connected to the connection element <NUM> in the ventilation orientation as shown in <FIG>, the ventilation valve is opened by the ventilation element <NUM>. As shown in <FIG>, the ventilation element <NUM> comprises an external thread <NUM>, a cylindrical portion <NUM> and a valve opening portion <NUM>. When the ventilation element <NUM> is screwed into the connection element <NUM>, the valve opening portion <NUM> abuts against an operating pin of the ventilation valve. Once the ventilation element <NUM> is completely screwed into the connection element <NUM> and, thus, connected to the connection element <NUM> in the ventilation orientation, the valve opening portion <NUM> has pushed the operating pin of the ventilation valve so far that the ventilation valve is completely open. In the present embodiment, if the pressurized oil container <NUM> is connected to the connection element <NUM>, that is, the pressurized oil container <NUM> is screwed into the third internal thread <NUM>, the ventilation valve is equally opened. Once the ventilation valve is open, the second ventilation port <NUM> is connected to the surroundings via the ventilation line <NUM>, the open ventilation valve and the first ventilation port <NUM>, thus enabling ventilation of the oil reservoir <NUM>.

In <FIG>, the ventilation element <NUM> is shown connected to the connection element <NUM> in a storage orientation. In comparison with <FIG>, the ventilation element <NUM> is turned by <NUM> degrees and has been pushed over the connection element <NUM> to form a plug-on connection. For this purpose, the inner diameter of the cylindrical portion <NUM> of the ventilation element <NUM> is slightly larger than the external diameter of the connection element body <NUM>. When the ventilation element <NUM> is connected to the connection element <NUM> in the storage orientation as shown in <FIG>, the interior of the cylindrical portion <NUM> covers the opening in the side wall of the connection element body <NUM>, that is, the first ventilation port <NUM>.

While the ventilation element <NUM> and the connection element <NUM> of the present embodiment are cylindrically shaped, these components can, of course, also have different matching shapes. As can also be seen in <FIG>, the external thread <NUM> of the ventilation element <NUM> is pointing away from the connection element <NUM> when the ventilation element <NUM> is connected to the connection element <NUM> in the storage orientation so that a protection cap (not shown) can be screwed onto the external thread <NUM> of the ventilation element <NUM>.

When the pressurized oil container <NUM> is connected to the connection element <NUM>, that is, when the pressurized oil container <NUM> is screwed into the third internal thread <NUM>, the oil valve arranged in the oil line <NUM> is opened in a generally known manner by the pressurized oil container <NUM>. Accordingly, the valve in the pressurized oil container is also opened so that the flexible oil chamber <NUM> is connected to the second oil port <NUM> via the first oil port <NUM>, the oil line <NUM> and the open oil valve.

As can be seen in <FIG>, the connection element <NUM> further comprises a fourth internal thread <NUM> and a fifth internal thread <NUM>. The fourth internal thread <NUM> is provided in the second ventilation port <NUM> for connecting the second end of the ventilation pipe <NUM> to the second ventilation port <NUM> of the connection element <NUM>. The fifth internal thread <NUM> is provided in the second oil port <NUM> for connecting the second end of the oil pipe <NUM> to the second oil port <NUM> of the connection element <NUM>.

A method for servicing the vacuum pump <NUM> of the service unit <NUM> for a vehicle air conditioning system will now be described with respect to <FIG>. The method basically comprises the steps of draining used vacuum pump oil from the oil reservoir <NUM> of the vacuum pump <NUM> of the service unit <NUM> and refilling the oil reservoir <NUM> with fresh vacuum pump oil.

Initially, the vacuum pump servicing adapter <NUM> will usually be in the storage state. That is, the protection cap is connected to the external thread <NUM> of the ventilation element <NUM> which is connected to the connection element <NUM> in the storage orientation as shown in <FIG>. As shown in <FIG>, after removing the protection cap, the ventilation element <NUM> is first removed from the connection element <NUM>, turned by <NUM> degrees and then connected to connection element <NUM> in the ventilation orientation, see <FIG>. That is, the external thread <NUM> of the ventilation element is screwed into the third internal thread <NUM> of the connection element <NUM> until the valve opening portion <NUM> of the ventilation element <NUM> has opened the ventilation valve of the connection element <NUM>. In this ventilation state, the oil reservoir <NUM> is connected to the surroundings via the ventilation connection <NUM>, the ventilation pipe <NUM>, the second ventilation port <NUM>, the ventilation line <NUM>, the open ventilation valve and the first ventilation port <NUM>.

As shown in <FIG>, air may flow out from the oil reservoir <NUM> to the surroundings due to pressure that has built in the oil reservoir <NUM>. After the oil reservoir <NUM> has been ventilated into the surroundings, an oil pan <NUM> is located under the oil drain <NUM> and the oil drain <NUM> is opened, as shown in <FIG>. Thus, the used vacuum pump oil contained in the oil reservoir <NUM> will flow out of the oil drain <NUM> into the oil pan <NUM>. After all the used oil has been drained into the oil pan <NUM>, the oil drain <NUM> is closed again.

As can be seen in <FIG>, in the present embodiment, the ventilation element <NUM> is removed again from the connection element <NUM> after the used oil has been drained from the oil reservoir <NUM> via the oil drain <NUM>.

Next, the oil reservoir <NUM> is refilled with fresh vacuum pump oil. For this purpose, the pressurized oil container <NUM> is connected to the connection element <NUM> as shown in <FIG>. When the pressurized oil container <NUM> is connected to the connection element <NUM>, the oil valve and the ventilation valve are opened by the pressurized oil container <NUM>. Thus, the oil reservoir <NUM> is connected to the flexible oil chamber <NUM> of the pressurized oil container <NUM> via the oil inlet <NUM>, the oil pipe <NUM>, the second oil port <NUM>, the oil line <NUM>, the open oil valve and the first oil port <NUM>. Now, the fresh vacuum pump oil contained in the flexible oil chamber <NUM> is pushed into the oil reservoir <NUM> by the pressure in the rigid pressure chamber <NUM> until the flexible oil chamber <NUM> is essentially empty. While the fresh vacuum pump oil is flowing into the oil reservoir, air can leave the oil reservoir via the ventilation connection <NUM>, the ventilation pipe <NUM>, the second ventilation port <NUM>, the ventilation line <NUM>, the open ventilation valve and the first ventilation port into the surroundings so that no undesirable pressure will build in the oil reservoir <NUM>.

Once the pressurized oil container <NUM> is empty, the pressurized oil container <NUM> is removed from the connection element <NUM> again which closes both the oil valve and the ventilation valve.

The pressurized oil container <NUM> is configured so that it contains the correct amount of vacuum pump oil necessary for refilling the oil reservoir <NUM> of the vacuum pump <NUM>. This ensures that the amount of vacuum oil refilled into the oil reservoir <NUM> is automatically neither too large nor too small because the pressure in the rigid pressure chamber <NUM> will reliably empty the flexible oil chamber <NUM> containing the correct amount of vacuum pump oil for the vacuum pump <NUM> into the oil reservoir <NUM>. It will, therefore, be obvious to the skilled person that providing the inspection glass <NUM> to the vacuum pump <NUM> and making it visible from outside the housing <NUM> is only required if a non-pressurized oil container is used in connection with a pump for refilling the oil reservoir <NUM> in an alternative embodiment of the present invention.

Finally, the vacuum pump servicing adapter <NUM> is put into the storage state again. The protection cap is connected to the ventilation element <NUM> and the ventilation element <NUM> is connected to the connection element <NUM> in the storage orientation. That is, the protection cap is screwed onto the external thread <NUM> of the ventilation element <NUM> and the cylindrical portion <NUM> of the ventilation element <NUM> is pushed over the connection element body <NUM> of the connection element <NUM>. In the storage state, the vacuum pump servicing adapter <NUM> is closed to and protected from the surroundings. The spring-loaded oil valve and the spring-loaded ventilation valve are automatically closed by their respective spring forces once the pressurized oil container <NUM> is removed from the connection element <NUM>, the first ventilation port <NUM> is covered by the cylindrical portion <NUM> of the ventilation element <NUM> and the first oil port is covered by the protection cap on the ventilation element <NUM>.

Claim 1:
Vacuum pump servicing adapter (<NUM>) for servicing a vacuum pump (<NUM>) of a service unit (<NUM>) for a vehicle air conditioning system comprising a connection element (<NUM>) and a ventilation element (<NUM>),
wherein the connection element (<NUM>) is configured to be connected to an oil container (<NUM>) and characterised in that the ventilation element (<NUM>) is configured to be connected to the connection element (<NUM>) in a storage orientation and in a ventilation orientation.