Connection adapters, especially for air conditioning systems

Description

[0001] The invention relates to a connection adapter for establishing a detachable fluid connection between a first fluid system and a second fluid system, in particular for establishing a detachable fluid connection between a fluid system of an air conditioning system and the fluid system of an air conditioning service unit, wherein the connection adapter has a switching valve which can be actuated via an actuating element in order to selectively open and close a fluid connection between a pressure chamber provided in a housing of the connection adapter and a valve chamber provided in the housing, wherein the actuating element is designed as a rotary handle which can be screwed into a threaded bore of a housing for actuating the switching valve, wherein a venting path leads from the valve chamber out of the connection adapter, which venting path can be closed and opened by a venting lock.wherein a fluid connection from the pressure chamber to the first fluid system can be established via a connection element, wherein the valve chamber is in fluid communication with a quick-release socket for connecting a connection element of the second fluid system, wherein the connection adapter has a locking mechanism for the quick-release socket and wherein the locking mechanism is restricted to a locked position when the venting block closes the venting path.

[0002] Connection adapters are used, for example, to create a secure and detachable connection between two fluid systems. This is necessary, for instance, to connect air conditioning systems, particularly automotive air conditioning systems, to an air conditioning service unit or refrigerant storage tank for filling or servicing. Previous solutions for connection adapters for filling / emptying air conditioning systems, especially those in the automotive industry that use CO2 as a refrigerant, are based on existing solutions for other refrigerants and do not meet the high sealing requirements while simultaneously offering a long service life / operating cycles.

[0003] Furthermore, existing solutions do not offer long-term durability of the sealing systems while maintaining high levels of tightness during operation under pressure, especially when CO2 is used as a refrigerant. Either a second energy source is required for operation, or mechanically vulnerable sealing systems are used. The reasons for this are primarily found in the sealing systems or sealing arrangements for the venting function.

[0004] DE 10 2009 012 267 A1 discloses a 3 / 2-way valve switchable via two rocker valves for connecting a service unit to an air conditioning system. Both rocker valves are actuated by a common control piston, with one rocker valve being the main valve that connects or disconnects the fluid systems of the service unit and the air conditioning system, and the other rocker valve serving for venting.

[0005] WO 2004 / 005787 A1 and US 2003 / 0140971 A1 each disclose a device according to the preamble of claim 1, or a method according to the preamble of claim 5.

[0006] The aim of the invention is to create a connection adapter that avoids the disadvantages of the prior art, is simple and safe to use, and has high stability.

[0007] According to the invention, these and further objectives are achieved by a connection adapter of the type mentioned above, in which the venting stop moves axially with the actuating element when the actuating element is actuated, wherein the actuating element can be brought into contact with a valve head of the switching valve when screwed in, after the venting stop has closed the venting path, wherein by further moving the actuating element towards the quick-release bushing the fluid connection between the pressure chamber and the valve chamber can be opened by moving a closure part and a valve pin of the switching valve towards the quick-release bushing.

[0008] Advantageously, the actuating element is designed as a rotary handle that can be screwed into a threaded bore in a housing to actuate the switching valve. This allows for intuitive, simple, and safe operation in a compact design.

[0009] In an advantageous embodiment, the actuating element, when screwed in, comes into contact with a valve head of the switching valve after the venting stop has closed the venting path. This ensures that premature opening of the main valve (i.e., while the venting path is still open) is not possible.

[0010] Advantageously, the actuating element can have a stop that blocks the locking mechanism in the locked position when the venting stop closes the venting path. This represents a structurally simple and effective measure to restrict the locking mechanism according to the invention.

[0011] In another advantageous embodiment, the venting barrier can be designed as a sleeve and arranged to be slidable on the housing along a valve axis. This allows for a structurally simple implementation with a minimum of moving parts.

[0012] Preferably, a sealing element can be provided on the housing, against which the venting barrier engages to create a seal when the vent passage is closed. Simple, cost-effective, and durable sealing elements, such as an O-ring, can be used for this purpose.

[0013] In a further advantageous embodiment, the actuating element can be rotatably connected to the venting stop. This allows the venting stop to move axially in a purely translational manner with the actuating element, without being coupled to the rotational movement of the actuating element. Furthermore, the permissible extent of movement of the actuating element can be easily limited via the venting stop.

[0014] The present invention is described below with reference to the Figures 1 to 3 In more detail, the invention is explained, and exemplary, schematic, and non-restrictive embodiments are shown. This includes showing Fig. 1 a sectional view of the connection adapter according to the invention in a first position, Fig. 2 the connection adapter of Fig. 1 in a second position and Fig. 3 the connection adapter of Fig. 1 in a third position.

[0015] The connection adapter 11 according to the invention has a housing 3 which includes a pressure chamber 12. The pressure chamber 12 is essentially designed as a central recess or bore extending along a valve axis 13, in which a switching valve 4 is arranged to be displaceable along the valve axis 13. A supply line 14 opens into the pressure chamber 12 transversely to the valve axis. A connection element 15 is provided on the supply line, via which the connection adapter 11 is connected, for example, via a line to a service device or a coolant storage tank. Fig. 1 A first fluid system 37 is shown schematically, with which the supply line or the connection element is connected.

[0016] The switching valve 4 has a closing element 7 on one side, which in the closed position of the switching valve 4 ( Fig. 1 and 2The pressure chamber 12 is sealed at a conical valve surface 16. On the side of the pressure chamber 12 axially opposite the valve surface 16, the pressure chamber 12 is limited by a fittingly enlarged diameter of the switching valve 4 and sealed with corresponding sealing elements 17. The end of the switching valve 4 axially opposite the closure element 7 has a substantially mushroom-shaped valve head 18, to which a valve spring 19 is attached, pressing the switching valve 4 into the closed position.

[0017] The housing 3 has an axial threaded bore 20 on the side of the valve spring 19 and the valve head 18, into which an actuating element 5, designed as a rotary handle and with an adjusting thread 21, is screwed in and out. By screwing in the actuating element 5, it comes into contact with the valve head 18 ( Fig. 2) and subsequently pushes the valve head 18 and thus the entire switching valve 4 against the force of the valve spring into an open position (as described in Fig. 3 (as shown).

[0018] On the side of the valve surface 16, a part of the housing 3 is designed as a connection sleeve 22, wherein the connection sleeve 22 has a quick-release socket 23 with which the connection adapter 11 can be connected to a correspondingly designed connection element 35 (in Fig. 2 and 3(schematically shown), for example, a service connection of a vehicle air conditioning system. In a known manner, locking balls 25 are inserted in radial bores 24, which are provided in the connection sleeve 22 in the area of ​​the quick-release socket 23. These locking balls are pressed into the radial bores 23 (which taper towards the inner wall of the connection sleeve 22) by a locking sleeve 1 pushed onto the connection sleeve 22, such that they protrude into the quick-release socket 23. They either secure a connection element 35 inserted therein or block the insertion of such a connection element 35 into the quick-release socket 23. The spring-loaded locking sleeve 1 and the locking balls 25 inserted into the bores 23 thus form a locking mechanism 39 for the quick-release socket 23.

[0019] To connect and remove the connecting element 35, the locking sleeve 1 is slidably retracted against the pressure of a tension spring 26 on the connecting sleeve 22 until an extended area 33 of the locking sleeve 1 is positioned over the locking balls 25, allowing the balls to "disengage" into the extended area 33 and thus enabling the connecting element to be inserted and removed. The connecting sleeve 22 can be made in one or more parts and can be detachably or permanently connected to the other parts of the housing 3. If necessary, the housing 3 can also be made in one piece, provided this is feasible from a manufacturing perspective.

[0020] A connection seal 8 is provided in the quick-release socket 23 to seal the connection element 35 inserted into the quick-release socket 23. The closure part 7 of the switching valve 4 has a valve pin 27 on its side facing away from the pressure chamber, projecting axially towards the quick-release socket 23, the end of which extends into the area of ​​the quick-release socket 23. The valve pin 27 serves to press open a valve body of a shut-off valve 36, which may be provided in the connection element 35, when the connection element 35 is inserted into the quick-release socket 23 and the fluid connection is established. The valve pin 27 is preferably dimensioned such that it opens the shut-off valve 36 in the connection element 35 only when the switching valve 4 also opens and the valve pin 27, together with the closure part 7, moves axially in the opening direction, i.e., towards the quick-release socket 23 (see Fig. 2 and 3 ).

[0021] In the area between the quick-release socket 23 (or the end of a connection element inserted therein) and the closure part 7 abutting the valve surface 16 (the volume in this area is hereinafter referred to as the valve chamber 31), a number of vent channels 28 are radially arranged in the connection sleeve 22. Any residual pressure present in this area must be released through these channels before the connection element 35 is removed from the quick-release socket 23. Especially at the high pressures of approximately 150 bar required for CO2 air conditioning systems, it would pose a significant safety risk if the connection element 35 could be opened while residual pressure was still present, as the pressure would then escape uncontrollably and suddenly.

[0022] To seal the vent channels 28 for "normal" valve operation, a sleeve-like vent stop 2 is slidably arranged on the housing. The vent stop 2 has a guide slot 30 into which a guide element 9 provided on the housing 3 engages, securing the vent stop 2 against rotation. The guide element 9 can optionally also project beyond the outer wall of the vent stop 2 and engage in a corresponding groove in the locking sleeve 1, thus also securing the locking sleeve against rotation. When the vent stop 2 is moved towards the quick-release bushing 23, it first covers the outer openings of the vent channels 28 and then engages with a sealing element 6 (several sealing elements may be provided if necessary), which is located on the outer wall of the connecting sleeve 22, orin corresponding sealing grooves provided in the connecting sleeve. The venting barrier 2 thus seals the vent channels 28 pressure-tight as soon as the venting barrier 2 has been moved sufficiently far towards the quick-release bushing 23 (. Fig. 2 and 3 The sealing element 6, which is located opposite the vent channels 28 on the side of the quick-release bushing 23, is arranged in a sealing groove formed by a holder 10 that can be screwed onto the connecting sleeve 22. This facilitates the replacement of this sealing element 6, which is subject to considerable stress due to its frequent engagement with the vent lock 2.

[0023] The locking sleeve 1 has vent holes 29 through which the space inside the locking sleeve 1 can be vented. Since the vent channels 28 also open into this space when the vent lock 2 is in its retracted position ( Fig. 1The valve chamber 31 can be vented by pushing back the venting lock 2 via the venting channels 28 and the venting bores 29. (In the context of the present invention, the direction "back" refers to the axial direction pointing away from the quick-release bushing 23).

[0024] At its rear end, i.e., the end furthest from the quick-release bushing 23, the vent stop 2 is rotatably connected to the actuating element 5 via a ball bearing 32. The ball bearing 32 allows the actuating element 5 to rotate relative to the vent stop 2. This causes the vent stop 2 to move axially with the actuating element 5 without rotating with it. Thus, the actuation of the closure part 7 (i.e., the main valve of the connector adapter), the actuation of the valve pin 27, which opens the shut-off valve 36 of the connector 35, and the displacement of the vent stop 2 are all possible with a single actuating element 5. Simultaneously, the maximum possible deflection of the actuating element 5 is limited by the guide slot 30 and the guide element 9.

[0025] The use of the connection adapter 11 is described below with reference to the Figs. 1 to 3 An example is provided. The in Fig. 1 The initial position shown depicts the connection adapter 11 in an inactive position, with the sealing element 7 holding the main valve closed, the venting path 40 defined by the vent channels 28 and the vent bores 29 being open, and the valve pin 27 projecting freely into the area of ​​the quick-release bushing 23, where no connection element 35 is yet located. The connection adapter 11 is connected to the first fluid system 37, for example, an air conditioning service unit, via the connection element 15. This unit is used to drain old refrigerant from a vehicle air conditioning system, evacuate the system, and refill it with fresh refrigerant and lubricant.

[0026] In order to establish a connection to a second fluid system 38 via the quick-release socket 23, which for example includes the lines of a vehicle air conditioning system, a connection element 35 suitable for the quick-release socket 23 is provided for the second fluid system 38 ( Fig. 2 ).

[0027] To establish a connection between the first fluid system 37 and the second fluid system 38, for example for air conditioning service or for the initial filling of an air conditioning system, the connection element 35 is inserted into the quick-release socket 23 of the connection adapter 11. For this purpose, the locking sleeve 1, which slides on the vent stop 2, must be retracted until the extended area 33 of the locking sleeve 1 releases the locking balls 25 sufficiently to allow the connection element 35 to be fully inserted into the quick-release socket 23, i.e., until the locking mechanism 39 is open. The connection element 35 is then sealed by the connection seal 8, but the valve pin 27 is in a position where the shut-off valve 36 in the connection element 35 is not yet open.This connection process is only possible when the actuating element 5 is in its fully extended position, otherwise the locking sleeve 1 would be abutting a stop 34 on the actuating element at its rear end before the locking balls 25 are released. This also ensures that the venting lock 2 is in the retracted position, in which the vent channels 28 are open and the vent path 40 is clear.

[0028] To establish the fluid connection between the first fluid system 37 and the second fluid system 38, the actuating element 5 is now turned and screwed in, whereby initially only the venting stop moves with the actuating element 5 and closes the venting channels 28, so that the valve chamber 31 is now hermetically sealed. This position is in Fig. 2As shown. It should be noted that in this position, although the main valve and the shut-off valve 36 are still closed, it is no longer possible to release the lock of the quick-release bushing 23, since the locking sleeve 1 would be abutting the stop 34 before the locking balls 25 would be released. The in Fig. 2 The depicted position also shows that the actuating element 5 is already in contact with the valve head 18. Further screwing in of the actuating element 5 would therefore move the switching valve 4, and thus the sealing element 7 and the valve pin 25, towards the quick-release bushing 23, and first open the main valve, i.e., create a fluid connection between the pressure chamber 12 and the valve chamber 31. Subsequently, the valve pin 27 then comes into contact with the shut-off valve 36 and opens it, so that a fluid connection is now also created between the valve chamber 31 and the second fluid system 38. This position is shown in Fig. 3 As shown, the stop 34 of the actuating element 5 now rests against, or almost rests against, the rear end of the locking sleeve 1, so that movement of the locking sleeve 1 is essentially no longer possible. Thus, a stable connection is created, and the various drainage, evacuation, and filling processes can now be carried out via the connection adapter.

[0029] To subsequently disconnect the connection between the connecting element 35 and the connecting adapter 11, the process described above is carried out in reverse, whereby the actuating element 5 is unscrewed from the threaded bore 20 of the housing 3. First, the shut-off valve 36 closes and the valve pin 27 detaches from the shut-off valve 36. Then, the sealing element 7 comes into contact with the valve surface 16, so that the main valve also closes (this corresponds again to the process described in...). Fig. 2(as shown). It should be noted that residual pressure exists in valve chamber 31 because vent channels 28 are still closed by the vent stop 2. The position of the stop 34 ensures that the quick-release bushing cannot be unlocked in this position. Only when the actuating element 5 is unscrewed far enough (i.e., into the position shown) Fig. 1 (as shown), and once the valve chamber 31 has been vented via the now open vent channels 28 and vent bores 29 (which form the vent path 40), it is possible to retract the locking sleeve 1 far enough to release the locking balls 25 and thereby release the locking mechanism 39. Now the connecting element 35 can also be pulled out of the quick-release socket 23 and the connecting adapter 11 is again in the position shown. Fig. 1 initial situation shown.

[0030] The above description represents, purely by way of example, a preferred embodiment of the invention. However, it is clear to those skilled in the art that the invention can also be implemented in other ways. For example, it is not necessary for the connection adapter to be connected to the service unit and to the connection element of the air conditioning system via the quick-release socket 23; instead, the connection adapter 11 can also form part of the air conditioning system. In this case, only one connection element would be required for the air conditioning service unit, which is plugged into the connection adapter of the air conditioning system. In general, the connection adapter according to the invention can be advantageously used as a valve for various applications in which two fluid systems are to be connected. Reference symbol list:

[0031] Locking sleeve (1) Venting stop (2) Housing 3 Switching valve (4) Actuating element (5) Sealing element (6) Closure part 7 Connection seal 8 Guide element 9 Holder (10) Connection adapter 11 Pressure chamber 12 Valve shaft 13 Supply line 14 Connection element 15 Valve surface 16 Sealing elements 17 Valve head 18 Valve spring 19 Threaded bore 20 Adjusting thread 21 Connection sleeve 22 Quick-release bushing 23 Radial bores 24 Locking balls 25 Tension spring 26 Valve pin 27 Venting channels 28 Venting holes 29 Guide slot 30 Valve chamber 31 Ball bearing 32 Extended area 33 Stop 34 Connection element 35 Shut-off valve 36 First fluid system 37 Second fluid system 38 Locking mechanism 39 Venting path 40

Claims

1. A device for connecting a first fluid system (37) and a second fluid system (38), comprising a connection adapter (11), - wherein a connection element (35) can be inserted into a quick fastener socket (23) of the connection adapter (11), - wherein the connection adapter (11) has a switching valve (4), which is actuatable by an actuation element (5), to selectively open and close a fluid connection between a pressure chamber (12) provided in a housing (3) of the connection adapter (11) and a valve chamber (31) provided in the housing (3) via a closing part (7) on the switching valve (4), wherein the closing part (7) has a valve pin (27) projecting axially in the direction of the quick fastener socket (23) on its side facing away from the pressure chamber (12), the end of the valve pin (27) extending into an area of the quick fastener socket (23), - wherein the actuation element (5) is designed as a rotary knob, which is screwable into a threaded bore (20) of the housing (3) for actuating the switching valve (4), - wherein a ventilation path (40) leads out of the connection adapter (11) from the valve chamber (31), which ventilation path (40) can be closed off and opened by a ventilation shut-off means (2), - wherein a fluid connection can be established from the pressure chamber (12) to the first fluid system (37) by a connection element (15), - wherein the valve chamber (31) is fluidically connected to the quick fastener socket (23) for connecting the connection element (35) of the second fluid system (38), in which a locking valve (36) is provided, and - wherein the connection adapter (11) has a locking mechanism (39) for the quick fastener socket (23), which is formed by a spring-loaded locking sleeve (1) and locking balls (25) inserted into radial bores (24), characterized in that the locking sleeve (1) sliding on the ventilation shut-off means (2) can be retracted, whereby an enlarged region (33) of the locking sleeve (1) releases the locking balls (25) to such an extent that the connection element (35) can be completely inserted into the quick fastener socket (23), wherein the connection element (35) can be sealed by a connection seal (8), and the valve pin (27) is in a position, in which the locking valve (36) in the connection element (35) is not open, and wherein the actuation element (5) is in a maximum turned-out position, in which ventilation channels (28) are open and the ventilation path (40) is unblocked; that the ventilation shut-off means (2) can be moved together with the actuation element (5) by turning and screwing the actuation element (5) and closes the ventilation channels (28), so that the valve chamber (31) can be hermetically sealed, wherein a main valve and also with the locking valve (36) are also still closed, wherein the actuation element (35) has a mechanical stop (34) blocking the locking mechanism (39) in the locked position, when the ventilation shut-off means (2) closes the ventilation path (40), wherein a lock of the quick fastener socket (23) can no longer be released, since the locking sleeve (1) abuts against the mechanical stop (34) provided on the actuation element (5) before the locking balls (25) can be released, and wherein the actuation element (5) is already in contact with a valve head (18); that by further screwing in the actuation element (5), the switching valve (4) and thus the closing part (7) and the valve pin (27) can be moved towards the quick fastener socket (23) and first open the main valve to establish the fluid connection between the pressure chamber (12) and the valve chamber (31), and that by further screwing in the actuation element 85), the valve pin (27) can be added to the locking valve (36) and opens the locking valve (36) to establish a fluid connection between the valve chamber (31) and the second fluid system (38) in the connection element (35), wherein the mechanical stop (34) of the actuation element (5) now abuts against a rear end of the locking sleeve (1), so that it is no longer possible to move the locking sleeve (1).

2. The device according to claim 1, characterized in that the ventilation shut-off means (2) is shaped like a sleeve and is arranged on the housing (3) so that it may slide along a valve axis (13).

3. The device according to claim 2, characterized in that a sealing element (6) is provided on the housing (3), wherein the ventilation shut-off means (2) comes into sealing engagement with the sealing element upon closing off the ventilation path (40).

4. The device according to any of the claims 1 to 3, characterized in that the actuation element (5) is rotatably connected to the ventilation shut-off means (2).

5. A method for connecting a first fluid system (37) with a second fluid system (38), - wherein a connection element (35) is inserted into a quick fastener socket (23) of the connection adapter (11), - wherein the connection adapter (11) has a switching valve (4), which is actuated by an actuation element (5), to selectively open and close a fluid connection between a pressure chamber (12) provided in a housing (3) of the connection adapter (11) and a valve chamber (31) provided in the housing (3) via a closing part (7) on the switching valve (4), wherein the closing part (7) has a valve pin (27) projecting axially in the direction of the quick fastener socket (23) on its side facing away from the pressure chamber (12), the end of the valve pin (27) extending into an area of the quick fastener socket (23), - wherein the actuation element (5) is designed as a rotary knob, which is screwed into a threaded bore (20) of the housing (3) for actuating the switching valve (4), - wherein a ventilation path (40) leads out of the connection adapter (11) from the valve chamber (31), which ventilation path (40) is closed off and opened by a ventilation shut-off means (2), - wherein a fluid connection is established from the pressure chamber (12) to the first fluid system (37) by a connection element (15), - wherein the valve chamber (31) is fluidically connected to the quick fastener socket (23) for connecting the connection element (35) of the second fluid system (38), and - wherein the connection adapter (11) has a locking mechanism (39) for the quick fastener socket (23), which is formed by a spring-loaded locking sleeve (1) and locking balls (25) inserted into radial bores (24), characterized in that for connecting, the following steps are performed: a) Retracting of the locking sleeve (1) sliding on the ventilation shut-off means (2), whereby an enlarged region (33) of the locking sleeve (1) releases the locking balls (25), and the connection element (35) is completely inserted into the quick fastener socket (23) and is sealed by a connection seal (8) and the valve pin (27) is in a position, in which the locking valve (36) in the connection element (35) is not open, and wherein the actuation element (5) is in a maximum turned-out position, in which ventilation channels (28) are open and the ventilation path (40) is unblocked; b) turning and screwing in of the actuation element (5), wherein first only the ventilation shut-off means (2) is moved together with the actuation element (5) and closes the ventilation channels (28), so that the valve chamber (31) can be hermetically sealed, wherein a main valve and also with the locking valve (36) are also still closed, wherein the actuation element (35) has a mechanical stop (34) blocking the locking mechanism (39) in the locked position, when the ventilation shut-off means (2) closes the ventilation path (40), wherein a lock of the quick fastener socket (23) can no longer be released, since the locking sleeve (1) would abut against the mechanical stop (34) provided on the actuation element (5), before the locking balls (25) can be released, and wherein the actuation element (5) is already in contact with a valve head (18) to ensure that a premature opening of the main valve is not possible; c) further screwing in of the actuation element (5), wherein the switching valve (4) and thus the closing part (7) and the valve pin (27) are moved towards the quick fastener socket (23), wherein first the main valve is opened to establish the fluid connection between the pressure chamber (12) provided in the connection element (35) and the valve chamber (31); d) further screwing in of the actuation element (5), wherein the valve pin (27) is added to the locking valve (36) and the locking valve (36) is opened, so that a fluid connection between the valve chamber (31) and the second fluid system (38) in the connection element (35) is established, wherein the mechanical stop (34) of the actuation element (5) now abuts against a rear end of the locking sleeve (1), so that it is no longer possible to move the locking sleeve (1).