Connection device for a test leak device

Abstract

The invention relates to a connection device (20) for connecting a test leak device (10) to a gas leak detection device (42) in order to check the proper working of the gas leak detection device or to calibrate the gas leak detection device. The test leak device (10) comprises an interior for holding a test fluid, said interior being surrounded by a test leak housing (12), and a test leak opening (16) which connects the interior to the external surroundings, and the gas leak detection device is designed to detect gas exiting from a device under test. The connection device comprises a first connection point (18) for the test leak device (10), a second connection point (28) for the gas leak detection device (42), and a connection channel (26) which connects the first connection point (18) to the second connection point (28). The first connection point (18) is provided with a carrier gas supply line (32) such that test fluid exiting from the test leak opening (16) is transported through the connection channel (26) to the second connection point (28) by carrier gas supplied via the carrier gas supply line (32).

Description

[0001] Connection device for a test leak device

[0002] The invention relates to a connecting device for connecting a test leak device to a gas leak detection device.

[0003] Gas leak detection devices typically have an evacuable test chamber into which a gas-filled or liquid-filled test specimen is placed. A gas analysis device—also referred to as a gas detector—is connected to the test chamber. This device analyzes the gas extracted from the test chamber to detect any leakage gas that has escaped into the test chamber from a leak in the test specimen, or liquid escaping and evaporating from the leak. It is particularly important to be able to determine the size of the leak from the amount of leakage gas detected. For this purpose, test leak devices are used. These contain a predetermined quantity of a known test gas or test fluid and are equipped with a leak with known dimensions and / or with known permeability for the fluid contained therein.Calibration leak detectors are typically used to check the functionality of a gas leak detection device and to calibrate the gas leak detection device.

[0004] Such a test leak device is described, for example, in WO 2021 / 259579 A1. The test leak device has a test leak housing enclosing an interior space, wherein the interior space accommodates a test fluid and is connected to the exterior of the test leak housing through a test leak opening in the test leak housing. The test leak opening can be closed, for example, by a membrane that is permeable to the test fluid. The test fluid can be a gas or a liquid. The test leak opening can, in particular, be formed in the base of the test leak device so that the test fluid escapes downward through the test leak opening due to the effect of gravity.

[0005] Conventionally, such test leak devices of the type described above are typically introduced into the test chamber of a gas leak detection device, with test fluid escaping from the test leak passing directly into the test chamber and from there being fed to the gas detector. However, it is also generally known to connect test leak devices to a gas leak detection device via a connection device, so that test fluid escaping from the test leak device passes through the connection device into the test chamber. The invention is based on the object of providing an improved connection device for connecting a test leak device to a gas leak detection device and an associated method.

[0006] The connection device according to the invention has a connection channel surrounded by a channel wall, which connects a first connection for the test leak device with a second connection for the gas leak detection device. The special feature of the invention is that a carrier gas supply line opens in the region of the first connection such that carrier gas flows from the carrier gas supply line into the region of the first connection and test fluid, which has escaped from the test leak device, is transported from the first connection through the second connection into the gas leak detection device, where it is detected by its gas detector. The carrier gas supply line can alternatively or additionally serve to supply a purge gas in order to purge the connection area for the test leak device and the downstream gas-carrying components of the connection device and the gas leak detection device with a purge gas.For the sake of simplicity, such a purge gas is also referred to as a carrier gas.

[0007] The test leak device generally comprises a test leak housing enclosing an interior space for the test fluid and having a test leak opening through which test fluid exits the interior space. The test leak opening can be closed with a membrane permeable to the test fluid. The test leak opening is preferably formed in a base of the test leak device or test leak housing, as described, for example, in WO 2021 / 259579 A1. The gas leak detection device typically comprises a test chamber for accommodating a test specimen to be tested or a connection for the test specimen to be tested, wherein the test chamber or connection is evacuated by a vacuum pump, and the evacuated gas from the test chamber or the test specimen is analyzed by a gas detector. In other words, the special feature of the invention is that a carrier gas process is used to transport test fluid leaked from the test leak device to the gas detector.

[0008] Conventional carrier gas methods are used to purge a test chamber to transport leak gas escaping from a test specimen into the test chamber to the gas detector. According to the invention, however, the carrier gas serves to purge a connection device for a test leak detection device without, however, surrounding the entire test leak detection device. This transports test fluid escaping from the test leak opening into the connection area through the connection channel to the gas leak detection device and its gas detector.

[0009] In the method according to the invention, the test leak device is connected to the first connection, while the second connection is connected to the gas leak detection device. The second connection is evacuated, preferably with the aid of the vacuum pump of the gas leak detection device, which can, for example, also evacuate a test chamber of the gas leak detection device or a connection for the test object. A carrier gas is supplied to the first connection via the carrier gas supply line. With the supplied carrier gas, test fluid leaked from the test leak device is transported through the connection channel into the gas leak detection device and detected by its gas detector.

[0010] Advantageously, the first connection of the connection device, when connected to the gas leak detection device, is configured to project upwards such that the test leak device can be placed on the first connection. A fluid-tight connection between the connection device and the test leak device can be created by evacuating the second connection. The vacuum generated in the connection channel draws the test leak device onto the first connection, thereby creating a stable, fluid-tight connection between the test leak device and the connection device. Separate mechanical connections or closure elements are then unnecessary or can be simplified.

[0011] Advantageously, the test leak device and in particular a region of the test leak device surrounding the test leak opening and the first connection are designed to be complementary to one another in order to create a positive connection between the test leak device and the first connection.

[0012] The carrier gas supply line is preferably guided through the channel wall of the connecting channel into the interior of the connecting channel and has a carrier gas outlet in the region of the first connection within the connecting channel. A carrier gas connection end of the carrier gas supply line opposite the carrier gas outlet is designed for connecting to a carrier gas source, such as a gas storage container.

[0013] The carrier gas supply line is preferably provided with a carrier gas shutoff valve that can be selectively opened and closed. When closed, the carrier gas shutoff valve seals the carrier gas supply line, preventing gas from passing from the carrier gas connection end to the carrier gas outlet. The carrier gas supply line can be provided with an adjustable flow restrictor that specifies a suitable carrier gas flow or is designed to selectively adjust a suitable carrier gas flow.

[0014] The connection device according to the invention advantageously has a connection valve for connecting to the gas leak detection device at the second connection. The connection valve can be selectively opened and closed. The second connection can, for example, be designed to be connected to a test chamber or the gas detector of the gas leak detection device. The conventional carrier gas method is described, for example, in EP 1 522 838 B1.

[0015] With the aid of the connection device according to the invention, carrier gas is not supplied to a test chamber to transport leak gas escaping from a test object to the gas detector. Rather, the carrier gas is guided into the connection area of ​​a test leak in order to transport test fluid escaping from the test leak directly into the connection device through the connection device and to the gas leak detection device. When the carrier gas is supplied to the gas leak detection device, it is already serving to transport test fluid, whereas with known carrier gas methods, the leak gas to be transported is first absorbed in the test chamber of a gas leak detection device.

[0016] The invention thus makes it possible to test and / or calibrate gas leak detection devices using test leak devices, where the test leak device does not necessarily have to fit into the test chamber of the gas leak detection device. Rather, the test leak device can be connected to the first connection of the connection device independently of the test chamber outside the gas leak detection device. In one embodiment, this is done by simply placing the test leak device on the first connection.

[0017] When the test leak device is connected to the connection device, the housing wall of the test leak housing is part of the outer wall of the vacuum system, which is formed by the gas leak detection device with its vacuum pump, the connection device, and the test leak device. This means that the vacuum pressure generated by the vacuum pump of the gas leak detection device is applied directly to the test leak opening of the test leak device due to the fluid-tight connection between the test leak housing and the connection channel. The test leak device is not surrounded by another outer wall of the vacuum system, such as a test chamber. With the help of the carrier gas, test fluid escaping from the test leak opening can be diverted from the connection area of ​​the first connection if the test fluid is not to be fed to the gas leak detection device.For this purpose, for example, an additional outlet of the connection valve at the second connection or a separate flushing valve of the connection device can be provided.

[0018] An exemplary embodiment of the invention is explained in more detail below with reference to the figure. The figure shows a schematic representation of a combination of a test leak device and a connection device with a leak detection device shown in dashed lines.

[0019] The test leak device 10 has a flat test leak housing 12 enclosing an interior space containing test fluid in the form of dimethyl carbonate. A test leak opening 16 is provided in a bottom surface 14 of the test leak housing 12, connecting the interior space to its external environment. A membrane selectively permeable to the test fluid is formed in the test leak opening 16. The test leak device 10 is connected in a vacuum-tight and fluid-tight manner to the first connection 18 of a connection device 20. For this purpose, the test leak device 10 is placed on an upwardly projecting connection flange 22. The connection flange 22 has a plane, a support surface 24 surrounding the first connection 18 on the outside, which contact the base 14 in a gas-tight manner. For this purpose, the connection flange 22 can have a sealing ring (not shown in the figure) that surrounds the first connection 18 on the outside.

[0020] The connection device 20 has a tubular connection channel 26, at one end of which the first connection 18 is formed and the other end of which has a second connection 28 for a gas leak detection device (not shown in the figure). The second connection 28 has a connection valve 30 in the form of a 3-2-way valve. A first connection of the connection valve 30 is connected to the second connection 28 of the connection device 20. A second connection of the connection valve 30 is connected to the gas leak detection device, for example, to a complementary connection of a test chamber of the gas leak detection device. A third connection of the connection valve 30 is open to the atmosphere and serves to purge the connection area of ​​the first connection 18 with carrier gas if this is not to be supplied to the gas leak detection device via the second connection of the connection valve 30.

[0021] A carrier gas supply line 32 is led from the outside into the interior of the connection channel 26 and opens into a carrier gas outlet 34 within the connection channel 26 and within the connection flange 22 in the region of the first outlet 18. The carrier gas outlet 34 is arranged concentrically within the connection channel 26 and within the first connection 18 and points directly to the test gas opening 16. The end of the carrier gas supply line 32 opposite the carrier gas outlet 34 forms a carrier gas connection end 38 outside the connection channel 26 for connecting a carrier gas source.

[0022] The carrier gas supply line 32 has a carrier gas shutoff valve (not shown in the figure) for selectively opening or closing the carrier gas supply line 32. Furthermore, the carrier gas supply line 32 is provided with an adjustable flow restrictor 40 for setting a suitable carrier gas flow.

[0023] The gas leak detection device 42 is shown in dashed lines in the figure to clarify that it is not part of the invention. Accordingly, the connection valve 30 is directly connected to a test chamber 44 for accommodating a test specimen. The test chamber 44 is vacuum-connected to a vacuum pump 46 for evacuating the test chamber 44. The test chamber 44 and the vacuum pump 46 are interconnected by a vacuum line 48. The vacuum line 48 contains a gas detector 50 for analyzing the gas extracted from the test chamber 44. When the connection valve 30 is open, the vacuum pump 46 evacuates the connection device 20. The vacuum resulting in the connection channel 26 draws the test leak device 10 onto the first connection 18, creating a vacuum-tight, stable connection between the test leak housing 12 and the connection flange 22.

[0024] A carrier gas source, not shown in the figure, can be connected to the carrier gas connection end 38, which can also serve as a carrier gas source for the test chamber 44. For this purpose, a direct connection can exist between the carrier gas source and the test chamber 44, which is formed separately and independently from the carrier gas supply line 32.

Claims

Claims 1. A connecting device (20) for connecting a test leak device (10) to a gas leak detection device (42) in order to check the functionality of the gas leak detection device or to calibrate the gas leak detection device, wherein the test leak device (10) has an interior space enclosed by a test leak housing (12) for receiving a test fluid and a test leak opening (16) connecting the interior space to the external environment, and the gas leak detection device is designed to detect gas escaping from a test object, with a first connection (18) for the test leak device (10), a second connection (28) for the gas leak detection device (42), a connection channel (26) connecting the first connection (18) to the second connection (28), characterized in that the first connection (18) is provided with a carrier gas supply line (32) such thatthat carrier gas supplied through the carrier gas supply line (32) transports test fluid emerging from the test leak opening (16) through the connection channel (26) to the second connection (28).

2. Connection device (20) according to claim 1, characterized in that the first connection (18) is designed to project upwards in the state mounted on the gas leak detection device (42) in such a way that by placing the test leak device (10) on the first connection (18) a fluid-tight connection is formed between the test leak device (10) and the connection channel (26).

3. Connection device (20) according to claim 1 or 2, characterized in that the carrier gas supply line (32) is guided through a channel wall of the connection channel (26) into its interior and forms a carrier gas outlet (34) in the region of the first connection (18).

4. Connection device (20) according to one of the preceding claims, characterized in that a carrier gas connection end (38) of the carrier gas supply line (32) opposite the carrier gas outlet (34) is designed for connection to a carrier gas source.

5. Connection device (20) according to one of the preceding claims, characterized in that the carrier gas supply line (32) has a carrier gas shut-off valve (40) for selectively closing the carrier gas supply line (32) or an adjustable flow restrictor (40) for selectively adjusting the carrier gas flow in the carrier gas supply line (32).

6. Connection device (20) according to one of the preceding claims, characterized in that the second connection (28) is provided with a connection valve (30) for the gas leak detection device (42).

7. Combination of a connection device (20) according to one of the preceding claims and a test leak device (10) which has an interior space enclosed by a test leak housing (12) for receiving a test fluid and a test leak opening (16) connecting the interior space to the external environment, characterized in that the test leak device (10) and the first connection (18) are designed to be complementary to one another in such a way that by placing the test leak device (10) on the first connection (18) a fluid-tight Connection is created between the test leak device (10) and the connection device (20).

8. A method for connecting a test leak device (10), which has an interior space enclosed by a test leak housing (12) for receiving a test fluid and a test leak opening (16) connecting the interior space to the external environment, to a gas leak detection device, using a connection device (20) according to one of claims 1-6, characterized by the steps Connecting the test leak device (10) to the first connection (18), Connecting the second connection (28) to the gas leak detection device (42), Evacuating the second port (28) by the leak detection device, Supplying carrier gas through the carrier gas supply line (32) to the first connection (18), Transporting test fluid emerging from the test leak opening (16) with the carrier gas through the connection channel (26) into the gas leak detection device (42), Detecting the transported test fluid with the gas detector (50).

9. Method according to the preceding claim, characterized in that the test leak device (10) is placed on the first connection (18) is connected to the connection channel (26) and a fluid-tight connection is established by evacuating the second connection (28).

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