JP2006079882A - Fuel cell system, leak inspection device, leak inspection method, and fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel cell system, a leak inspection device, a leak inspection method, and a fuel cell, capable of appropriately preventing working defects of a switching valve due to foreign substance. <P>SOLUTION: For the fuel cell system 1 provided with a switching valve 44 opening and closing a channel 41 of a piping line 3, a foreign substance capturing means 43 for capturing the foreign substance flowing in the channel 41 by working in interlocking with switching movements of the switching valve 44 is provided at the piping line 3 at an upstream of the switching valve 44. The foreign matter capturing means 43 can be constituted of a filter mechanism, in which case, a filter 91 is switched over to a use position prior to completion of closing of the switching valve 44. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a fuel cell and a fuel cell system, and a leak inspection apparatus and a leak inspection method for inspecting a gas leak of a test object such as a fuel cell stack.

  Generally, in addition to piping elements and fuel cell stacks on a gas piping line, a structure such as a container is required to be airtight, so a gas leakage inspection is performed by a leakage inspection device before being used in an actual machine. As this type of leak inspection apparatus, for example, the one described in Patent Document 1 applied to a wafer container for housing a semiconductor wafer is known.

  This leak inspection apparatus includes an inspection container that can be filled with an inspection gas, and a pair of on-off valves that open and close an inlet-side passage and an outlet-side passage connected to the inspection container, respectively. In the leak inspection, first, a wafer container (inspected object) is placed inside the inspection container, the inspection gas flows into and out of the inspection container, and the inside of the inspection container is filled with the inspection gas. Thereafter, the on-off valve on the outlet side is closed while continuing the inflow of the inspection gas. After a predetermined time has elapsed, the on-off valve on the inlet side is closed to bring the inspection container and the wafer container into an airtight state. The leak characteristics of the wafer container are evaluated based on the pressure change in the inspection container in this state.

In addition, a fuel cell system that performs a gas leakage inspection is also known (see, for example, Patent Document 2). In this fuel cell system, on-off valves are provided in the fuel gas passages upstream and downstream of the fuel cell stack, and a predetermined closed space that is airtight is formed by closing these two on-off valves. The gas leakage is detected from the pressure change in the closed space in this state.
JP 2002-206985 (page 2 and FIG. 1) JP 2003-308866 A (page 5 and FIG. 1)

  However, in the leak inspection described in Patent Document 1, foreign matter may flow out of the wafer container during the flow of the inspection gas. If the foreign matter adheres to the outlet side on-off valve (particularly in the valve closing operation process) and the on-off valve is closed, the valve body and valve seat will be damaged. For this reason, at the time of leak inspection, leak may occur from the opening / closing valve portion, and there is a possibility that the leak inspection cannot be performed accurately.

  Also, in the fuel cell system described in Patent Document 2, foreign matter may flow out from the piping element or the like into the fuel gas passage, and there is a risk of damaging the on-off valve as described above.

  Of course, as a countermeasure against such foreign matter, it is conceivable to arrange a filter for capturing foreign matter on the passage on the upstream side of the on-off valve. However, even in this case, due to the influence of pressure loss due to filter clogging or the like, there is a possibility that the leak inspection cannot be performed accurately or the gas flow during system operation may be hindered.

An object of the present invention is to provide a fuel cell system that can appropriately prevent a malfunction of an on-off valve due to foreign matter.
It is another object of the present invention to provide a leak inspection apparatus, a leak inspection method, and a fuel cell that can appropriately prevent a malfunction of the on-off valve due to foreign matter and perform a leak inspection accurately.

  The fuel cell system of the present invention is a fuel cell system including an on-off valve that opens and closes a passage of a piping line. The piping line on the upstream side of the on-off valve operates in conjunction with the closing operation of the on-off valve. Foreign matter catching means for catching the foreign matter flowing through is provided.

According to this configuration, foreign matter can be prevented from flowing into the on-off valve by the foreign matter catching means operating in conjunction with the closing operation of the on-off valve. For this reason, adhesion of foreign matter to the on-off valve is prevented, and damage to the on-off valve due to foreign matter in the valve closing operation process can be effectively avoided. Thereby, the malfunction of an on-off valve can be prevented suitably.
Here, the “interlocking operation” of the foreign matter trapping means may be a mechanism that is mechanically performed with a valve closing operation of the on-off valve, or may be a configuration that is performed by electric / electronic control. The foreign matter catching means may be provided immediately upstream of the on-off valve, or may be provided upstream of the on-off valve with some structure interposed therebetween. In addition, examples of the foreign matter include dust, contaminated particles (so-called contamination) such as rust eluted from the piping elements of the piping line, and oil.
Here, the piping line may be an oxidizing gas or fuel gas supply line, a discharge line, a circulation line, or a fuel gas filling line to a high-pressure tank, for example. The piping line may be not only a gas piping line but also a refrigerant line for cooling the fuel cell.

  In this case, the foreign matter capturing means is configured by a filter mechanism having a filter facing the passage, and the filter mechanism is configured to be able to set the position of the filter with respect to the passage in conjunction with the opening / closing operation of the on-off valve. Is preferred.

  According to this configuration, foreign matter can be captured with a simple structure called a filter. Further, since the position of the filter can be set in conjunction with the opening / closing operation of the opening / closing valve, the specification can be made in consideration of the influence of pressure loss and the like.

  In this case, it is preferable that the filter mechanism switches between a use position and a non-use position of the filter with respect to the passage in conjunction with each opening / closing operation of the opening / closing valve.

According to this configuration, for example, when the gas is made to flow by opening the on-off valve, the influence of pressure loss can be avoided by setting the filter to the non-use position. Further, for example, when the gas flow is stopped by closing the on-off valve, the filter can be used as described above to prevent foreign matter from adhering to the on-off valve.
Here, the “non-use position” of the filter may be a configuration in which the filter is completely retracted from the passage, or may be a configuration in which the position of the filter in the passage is set so that the influence of pressure loss is reduced. Good. Also, the “use position” of the filter generally allows the fluid flowing through the pipeline to pass through the filter.

  In this case, the filter mechanism preferably switches the filter to the use position with respect to the passage in preference to the on-off valve closing the passage.

  According to this configuration, since the on / off valve is closed after the filter is switched to the use position, it is possible to reliably prevent the foreign matter from flowing into the on / off valve. Thereby, the malfunction of the on-off valve due to foreign matters in the valve closing operation process can be reliably prevented.

  In these cases, it is preferable that a plurality of filters having different filtration degrees are prepared.

  According to this configuration, it is possible to effectively deal with a plurality of types of foreign matters having different sizes. Note that filters may be prepared in stages from coarse meshes to fine meshes, or multiple types of filters combining meshes with different coarseness may be prepared.

  The leak inspection apparatus of the present invention includes an on-off valve that opens and closes a passage connected to the downstream side of the object to be inspected. The passage on the upstream side of the on-off valve is provided with foreign matter capturing means that operates in conjunction with the closing operation of the on-off valve and captures the foreign matter flowing through the passage.

According to this configuration, the foreign matter capturing means that operates in conjunction with the closing operation of the on-off valve can prevent foreign matter that can come out from the object to be inspected from flowing into the on-off valve. For this reason, adhesion of foreign matter to the on-off valve is prevented, and malfunction of the on-off valve due to foreign matter in the valve closing operation process can be suitably prevented. Thereby, since the leak from an on-off valve can be prevented appropriately, a leak test | inspection can be performed correctly.
Here, the “interlocking operation” of the foreign matter capturing means can be configured to be mechanically or electrically / electronically controlled with the closing operation of the on-off valve, as described above. Further, the arrangement position of the foreign matter capturing means is not limited to the upstream side of the on-off valve. The “passage connected to the downstream side of the object to be inspected” may be a case where the passage is directly connected to the object to be inspected, or by connecting the passage to an airtight sealed space, It may be a case where the passage is indirectly connected to the inspected object.

  As in the case of the fuel cell system described above, the foreign matter catching means is constituted by a filter mechanism having a filter facing the passage, and the filter mechanism is coupled to the opening / closing operation of the on-off valve to position the filter with respect to the passage. Is preferably configured to be settable. In addition, it is preferable that the filter mechanism switches between two positions of the use position and the non-use position of the filter with respect to the passage in conjunction with each opening / closing operation of the opening / closing valve. Further, the filter mechanism preferably switches the filter to the use position with respect to the passage in preference to the on-off valve closing the passage.

  In this case, it is preferable that the filter mechanism switches the filter to the non-use position with respect to the passage after the opening / closing valve is closed.

  According to this configuration, for example, the influence of pressure loss or the like can be avoided or reduced when the flow of the inspection gas is continued so that the object to be inspected is kept airtight after the opening / closing valve is closed.

  In these cases, it is preferable that a plurality of filters having different filtration degrees are prepared.

  According to this configuration, similarly to the above, it is possible to effectively cope with a plurality of types of foreign matters having different sizes and types of inspected objects.

  The leak inspection method of the present invention includes a step of connecting a passage provided with an opening / closing valve to the downstream side of the object to be inspected and making a portion of the passage between the opening / closing valve and the object to be inspected to be able to catch foreign matter. And a step of closing the open / close valve after this step to bring the device under test into an airtight state, and performing a leak inspection of the device under test based on a pressure change in the airtight space.

  According to this configuration, since the foreign matter that can come out from the object to be inspected can be captured upstream of the on-off valve, it is possible to prevent the foreign matter from adhering to the on-off valve during the valve closing operation process. For this reason, damage to the on-off valve due to foreign matters can be effectively avoided, and leakage from the on-off valve can be prevented at the time of leak inspection performed under airtightness. Therefore, since the pressure change in the airtight space depends on the object to be inspected, the inspected object can be accurately inspected for leak.

  The fuel cell of the present invention has been subjected to a leak test as an object to be inspected by the above-described leak test apparatus or leak test method of the present invention.

  According to this configuration, since the leak inspection is accurately performed, a highly reliable fuel cell can be provided.

  According to the fuel cell system of the present invention, malfunction of the on-off valve due to foreign matter can be prevented appropriately.

  According to the leak inspection apparatus and the leak inspection method of the present invention, it is possible to appropriately prevent a malfunction of the on-off valve due to a foreign substance and perform a leak inspection accurately. In addition, a highly reliable fuel cell can be provided.

  Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. The characteristic part of the present invention is that the foreign matter capturing means comprising a filter mechanism is provided upstream of the on-off valve that opens and closes the passage, and the filter mechanism is operated in conjunction with the closing operation of the on-off valve, thereby operating the on-off valve. It is intended to prevent defects. As an embodiment to which this is applied, a fuel cell system will first be described as a first embodiment, and a leak inspection apparatus will be described as a second embodiment.

<First Embodiment>
As shown in FIG. 1, the fuel cell system 1 includes a fuel cell 2 having a stack structure in which a large number of single cells are stacked. The fuel cell 2 generates power by receiving supply of air as an oxidizing gas and hydrogen gas as a fuel gas. As the fuel cell 2, there are various types such as a phosphoric acid type. Here, the fuel cell 2 is constituted by a solid polymer electrolyte type. The fuel cell system 1 having the fuel cell 2 of this type can be used for a stationary body such as a combined heat and power system as well as a mobile body such as a vehicle, an aircraft, and a ship.

  The piping line 3 of the fuel cell system 1 includes an oxidizing gas supply line 11 for supplying an oxidizing gas to the fuel cell 2, an oxidizing off gas line 12 for discharging the oxidizing off gas from the fuel cell 2, and a fuel cell 2. Hydrogen gas supply line 13 for supplying hydrogen gas, hydrogen off-gas circulation line 14 for circulating and supplying hydrogen off-gas discharged from the fuel cell 2 to the fuel cell 2 again, and for discharging hydrogen off-gas to the outside A hydrogen off-gas discharge line 15 and a hydrogen gas filling line 16 for filling the hydrogen gas supply source (high pressure tank 42) with hydrogen gas are provided. Although not shown, a refrigerant line for cooling the fuel cell 2 is also provided as the piping line 3.

  The supply passage 21 of the oxidant gas supply line 11 is provided with a compressor 23 that takes in air in the atmosphere and pumps it to the humidifier 22, and a filter 24 that filters dust and the like contained in the air taken in by the compressor 23. Has been. The humidifier 22 is provided over both the oxidizing gas supply line 11 and the oxidizing off gas line 12, and exchanges moisture between the purified oxidizing gas and the oxidizing off gas. The exhaust passage 31 of the oxidation off gas line 12 is provided with a pressure regulating valve 32 that adjusts the pressure of the oxidation gas in the fuel cell 2 and a silencer 33 that is located downstream of the humidifier 22 and silences the oxidation off gas. It has been.

  The supply passage 41 of the hydrogen gas supply line 13 extends from a high-pressure tank 42 that stores hydrogen gas at a high pressure to a gas inlet port of the fuel cell 2. In the supply passage 41, in order from the high-pressure tank 42 side, a filter mechanism 43 as foreign matter capturing means, an opening / closing valve 44 for opening / closing the supply passage 41, a manual valve 45 for manually opening / closing the supply passage 41, and hydrogen gas are supplied. A primary regulator 46 for reducing pressure, a secondary regulator 47 for further reducing hydrogen gas, and an inlet-side shut valve 48 for opening and closing the supply passage 41 are provided. Details of the filter mechanism 43 and the on-off valve 44 that are characteristic portions of the present embodiment will be described later.

  In the circulation passage 51 of the hydrogen off-gas circulation line 14, in order from the fuel cell 2 side, an outlet-side shut valve 52 that opens and closes the circulation passage 51, a gas-liquid separator 53 that separates moisture from the hydrogen off-gas, and hydrogen off-gas is supplied to hydrogen. A hydrogen pump 54 that pumps the gas to the gas supply line 13 and a check valve 55 that prevents backflow of hydrogen off-gas are provided. The circulation passage 51 is connected to the junction A of the supply passage 41, and the hydrogen off-gas circulated and supplied by the hydrogen pump 54 merges with the new hydrogen gas from the high-pressure tank 42 at the junction A. Is supplied to the fuel cell 2.

  The hydrogen off-gas discharge line 15 has a discharge passage 61 that is branched and connected to the circulation passage 51. The discharge passage 61 is provided with a purge valve 62 that is periodically opened and a gas processing device 63 such as a diluter into which hydrogen off-gas is sent through the purge valve 62 that is opened. The discharge passage 61 is branched from the downstream side of the gas processing device 63 to the oxidation off-gas discharge passage 31. The processing gas of the hydrogen off-gas processed by the gas processing device 63 merges with the oxidizing off-gas that has passed through the silencer 33 and is exhausted outside the system.

  In the filling passage 71 of the hydrogen gas filling line 16, in order from the high-pressure tank 42 side, a check valve 72 for preventing the backflow of hydrogen gas filling the high-pressure tank 42, a manual valve 73 for opening and closing the filling passage 71, And a filter 74 for capturing foreign substances that may be included in the hydrogen gas. The hydrogen gas is charged into the high-pressure tank 42 via the filter 74 by connecting the filling port 75 to a gas filling facility such as a hydrogen station and opening the manual valve 73. For example, in the case of a fuel cell vehicle, the filling port 75 is provided at the rear portion of the vehicle body.

  Here, the filter mechanism 43 and the on-off valve 44 of the hydrogen gas supply line 13 will be described in detail with reference to FIGS. The on-off valve 44 is a shut-off valve that opens or closes the supply passage 41 manually or electromagnetically. The on-off valve 44 is a valve of a type that uses the valve opening mainly in a fully open state or a fully closed state, or a valve that can adjust the valve opening. The on-off valve 44 can take various valve structures such as a gate valve, a ball valve, and a butterfly valve. In this embodiment, the on-off valve 44 is composed of a rotary valve that can adjust the opening degree of the valve electrically. Yes.

  The filter mechanism 43 is provided in the supply passage 41 on the upstream side of the on-off valve 44 and functions as a foreign matter capturing unit that captures the foreign matter flowing through the supply passage 41. Examples of the foreign matter include dust, contaminated particles such as rust eluted from the piping elements of the piping line 3 (so-called contamination), oil, and the like, but here, mainly foreign matter that can flow out from the high-pressure tank 42 is targeted.

  The filter mechanism 43 includes a filter 91 that faces the supply passage 41 and a filter operation mechanism (not shown) that sets the position of the filter 91 with respect to the supply passage 41. The filter 91 includes a filter element 93 having a filtration degree corresponding to the size of the target foreign matter, and a seal portion 94 provided at the peripheral edge of the filter element 93, and is formed in a substantially disc shape as a whole. Yes. The seal portion 94 is configured to be detachable from the inner wall of the supply passage 41.

  The filter element 93 has a mesh made of resin, stainless steel, brass, sintered metal, or the like. A plurality of meshes are prepared from coarse meshes to fine meshes, and the filter mechanism 43 is configured such that various filters 91 having different filtration degrees can be replaced with filter operation mechanisms. In the present embodiment, one filter 91 is used for one filter mechanism 43, but a plurality of filters 91 may be used instead. In this case, it is preferable that a plurality of types of filters 91 are juxtaposed from the upstream side of the supply passage 41 in descending order of filtration degree.

  The filter operating mechanism appropriately sets the filter 91 at a predetermined position in conjunction with the opening / closing operation of the opening / closing valve 44. For example, the filter operating mechanism includes an actuator that rotates the filter 91 around its axis in the supply passage 41 and a power transmission mechanism that transmits the power of the actuator to the filter 91. The actuator is driven in synchronism with the opening / closing valve 44 by electric / electronic control, so that the filter operating mechanism sets the filter 91 at a predetermined position (opening) in conjunction with the opening / closing operation of the opening / closing valve 44. To do.

  Specifically, the filter operating mechanism switches between the use position and the non-use position of the filter 91 with respect to the supply passage 41 in conjunction with the opening and closing operations of the opening / closing valve 44. In the non-use position (open state) of the filter 91, the filter 91 extends so as to be parallel to the hydrogen gas flow direction, and the resistance to the hydrogen gas flow is minimized. On the other hand, in the use position (closed state) of the filter 91, the filter 91 extends so as to be orthogonal to the flow direction of the hydrogen gas, the filter element 93 greatly faces the supply passage 41, and the seal portion 94 of the supply passage 41. Close to the inner wall of the tube.

  A series of operations of the filter mechanism 43 and the on-off valve 44 will be described with reference to FIGS. When the fuel cell system 1 is in operation, the on-off valve 44 is opened and hydrogen gas is supplied to the fuel cell 2. During this gas supply, the filter 91 of the filter mechanism 43 can be set to the non-use position as shown in FIG. 2, or can be set to the use position as shown in FIG.

  In general, by setting the filter 91 at the use position in FIG. 3, foreign matter that can flow out from the high-pressure tank 42 or the like can be captured on the upstream side of the fuel cell 2, for example, in consideration of circumstances such as pressure loss, The filter 91 can also be set at the non-use position in FIG. That is, the filter mechanism 43 can appropriately switch the position of the filter 91 in accordance with the open / close state of the on-off valve 44.

  When it is desired to stop the supply of hydrogen gas to the fuel cell 2 such as when the fuel cell system 1 is stopped, the on-off valve 44 is closed (the manual valve 45 and the inlet side shut valve 48 are also closed). In such a case, when the filter 91 is in the non-use position of FIG. 2, the filter 91 is first set to the use position of FIG. 3 before the on-off valve 44 closes the supply passage 41.

  That is, at the same time as the control command is output from the control device to the on-off valve 44, the filter mechanism 43 receives the control command from the control device, and uses the filter 91 with time priority over the closing of the on-off valve 44. Switch to position. The filter 91 at the use position prevents foreign matter from flowing into the on-off valve 44. After the filter 91 moves to the use position, the on-off valve 44 is closed as shown in FIG.

  As described above, according to the fuel cell system 1 of the present embodiment, the filter mechanism 43 operates in conjunction with the valve closing operation of the on-off valve 44, and after the filter 91 is switched to the use position, the on-off valve 44 is supplied to the supply passage. 41 is closed. As a result, it is possible to prevent foreign matter from adhering to the on-off valve 44 (the valve body thereof) during the valve closing operation process, so that damage to the on-off valve 44 due to the foreign matter during the valve closing operation process is effectively avoided. be able to.

  Therefore, the malfunction of the on-off valve 44 can be suitably prevented. In addition, the product life of the on-off valve 44 can be extended, and the number of replacement man-hours can be reduced. In this case, the filter mechanism 43 closes not only the on-off valve 44 immediately downstream thereof but also the manual valve 45 and the inlet-side shut valve 48 on the downstream side of the on-off valve 44. By interlocking with the valve operation, malfunction of these valves 45 and 48 is preferably prevented.

  In addition, this embodiment can take another modification in various points. For example, not only when the filter operating mechanism and the on-off valve 44 are electrically controlled as described above (controlled by the ECU), the filter operating mechanism and the on-off valve 44 are configured to be mechanically adjustable. By providing a link mechanism or the like between them, the filter operating mechanism may be mechanically interlocked with the opening / closing operation of the opening / closing valve 44. Further, although the filter 91 is rotated around its axis, the filter 91 may be configured as a swing type filter 91 such that the filter 91 can be rotated in the supply passage 41 via a hinge. However, when the filter 91 is in the use position, it is preferable that the sealing performance is secured through the seal portion 94.

  Further, the “non-use position (open state)” of the filter 91 may be configured such that the filter 91 is completely retracted from the supply passage 41. For example, a cylinder device is used as an actuator of the filter operation mechanism of the filter mechanism 43, and the filter 91 is coupled to a rod that is a power transmission mechanism of the cylinder device. In the case of this configuration, the rod 91 is extended by driving the cylinder device, so that the filter 91 faces the supply passage 41 as shown in FIG. On the other hand, by retracting the rod by driving the cylinder device, the filter 91 is moved out of the supply passage 41 and the filter 91 is set to the non-use position. In this case, needless to say, the filter mechanism 43 and the pipe of the supply passage 41 need to be hermetically sealed.

  Further, the filter mechanism 43 (foreign matter capturing means) can be applied not only to the hydrogen gas supply line 13 but also to various piping lines 3 of the fuel cell system 1. For example, when applied to the hydrogen gas filling line 16, the filter 74 may be configured as the filter mechanism 43 having the above configuration. In this case, the filter mechanism 43 sets the filter in the use position in conjunction with the closing operation of the check valve 72 and the manual valve 73. Further, the filter mechanism 43 may be interlocked with a structure other than the on-off valve 44.

  For example, when the filter mechanism 43 is provided in the oxidizing gas supply line 11, the filter mechanism 43 is provided on the upstream side of the compressor 23 instead of or together with the filter 24, and the filter mechanism 43 is interlocked with the driving of the compressor 23. be able to. During operation of the fuel cell system 1 driven by the compressor 23, the filter mechanism 43 sets the filter 91 to the non-use position in order to reduce the pressure loss of the oxidizing gas. On the other hand, when the fuel cell system 1 is stopped, the filter 91 is set to the use position in preference to the drive stop operation of the compressor 23, and it is possible to favorably avoid malfunction caused by foreign matter in the drive stop process of the compressor 23. it can. Similarly, when the filter mechanism 43 is provided in the hydrogen off-gas circulation line 14, it is possible to suitably prevent malfunction of the hydrogen pump 54.

Second Embodiment
Next, the leak inspection apparatus of the present invention will be described. FIG. 5 is a configuration diagram illustrating a main part of the leak inspection apparatus 110 according to the second embodiment. As shown in the figure, the leak inspection apparatus 110 includes an upstream passage 112a connected to the upstream side of the inspection object 111 to be inspected for leak inspection, and a downstream passage 112b connected to the downstream side of the inspection object 111. And.

  In the upstream passage 112a, in order from the upstream side, a filter mechanism 121a that functions as a foreign matter capturing means, an on-off valve 122a that opens and closes the upstream passage 112a, a pressure gauge 123a that detects the pressure in the upstream passage 112a, Is provided. Similarly, the downstream passage 112b includes, in order from the upstream side, a pressure gauge 123b that detects the pressure in the downstream passage 112b, a filter mechanism 121b that functions as a foreign matter capturing means, and an on-off valve that opens and closes the downstream passage 112b. 122b.

  The downstream end of the upstream passage 112a is detachably attached to the inlet port of the device under test 111. On the other hand, although not shown on the upstream end side of the upstream passage 112a, in addition to a gas supply source storing a test gas for leak inspection, a source pressure opening / closing valve serving as a first valve for the gas supply source In addition, a pressure reducing valve for reducing the pressure of the inspection gas from the gas supply source to the inspection object 111 is provided. As the inspection gas, an inert gas such as nitrogen gas or dry air can be used. The upstream end of the downstream passage 112b is detachably attached to the outlet port of the device under test 111, while the downstream end of the downstream passage 112b is open to the outside or a test gas recovery tank provided at this position. It is connected.

  The two upstream and downstream filter mechanisms 121a and 121b have a common structure, for example, the same structure as in the first embodiment. The two upstream and downstream on-off valves 122a and 122b have a common structure, for example, the same structure as in the first embodiment. Note that the two filter mechanisms 121a and 121b and the two on-off valves 122a and 122b may have different structures, but here, the same structure and the same structure as the first embodiment are used to avoid redundant description.

  By opening both the two on-off valves 122a and 122b, the inspection gas is exhausted from the downstream side passage 112b to the outside or the recovery tank via the device under test 111. On the other hand, by closing both the two on-off valves 122a and 122b, an airtight space (sealed space) is defined between the two on-off valves 122a and 122b with the object 111 to be inspected in between. That is, the inspected object 111 is placed in an airtight state.

  FIG. 6 shows the appearance of a fuel cell that is a typical example of the device under test 111. This fuel cell 111 can be applied to the fuel cell 2 of the fuel cell system 1 according to the first embodiment, and has a stack structure in which end plates 131 are arranged at both ends of a single cell in which a large number of layers are stacked. Has been. The end plate 131 on the near side in the figure is provided with a hydrogen gas inlet port 132a and an outlet port 132b, an oxidizing gas inlet port 133a and an outlet port 133b, and a refrigerant inlet port 134a. A refrigerant outlet port (not shown) is provided in the end plate 131 on the back side in the figure. In addition, the arrangement positions of the inlet ports 132a, 133a, and 134a and the outlet ports 132b and 133b of each fluid are arbitrary.

  The downstream end of the supply passage 41 and the downstream end of the upstream passage 112a of the first embodiment are detachably attached to the hydrogen gas inlet port 132a, and the circulation of the first embodiment is attached to the hydrogen gas outlet port 132b. The downstream end of the passage 51 and the upstream end of the downstream passage 112b are detachably mounted. In this case, both can be mounted via, for example, the quick joint 135. Similarly, the supply passage 21 and the upstream passage 112a are connected to the oxidation gas inlet port 133a, and the discharge passage 31 and the downstream passage 112b are connected to the oxidation gas outlet port 133b. The same applies to the refrigerant inlet port 134a and the outlet port. As described above, when the device under test 111 is a fuel cell, the flow path of each fluid (hydrogen gas, oxidizing gas, or refrigerant) in the fuel cell 111 is subjected to a leak test.

  Here, a series of leak inspections by the leak inspection apparatus 110 will be described with reference to FIGS. FIGS. 7 to 9 schematically show the filter mechanism 121b and the on-off valve 122b on the downstream side, and are the same views as FIGS. 2 to 4 of the first embodiment. FIG. 10 is a diagram schematically showing the upstream filter mechanism 121a and the on-off valve 122a.

  In the case of performing a leak inspection, from the state shown in FIG. 5 in which the upstream passage 112a and the downstream passage 112b are connected to the device under test 111, first, the filters 125a and 125b of the two filter mechanisms 121a and 121b are moved to the non-use positions ( Open), and then the two on-off valves 122a and 122b are opened. Then, as shown in FIG. 7, the inspection gas flows from the upstream side to the downstream side so as to pass through the inspection object 111. At this time, since the filters 125a and 125b are set to the non-use positions, the inspection gas flows without being affected by the pressure loss as much as possible. When a predetermined time elapses, the air present in the inspection object 111 (for example, a predetermined fluid flow path in the fuel cell 111) is replaced with the inspection gas.

  After gas replacement, as described in the first embodiment, for example, the control device outputs a valve closing control command to the downstream on-off valve 122b. At this time, the downstream filter mechanism 121b that receives a control command from the control device switches the filter 125b to the use position in preference to the closing of the on-off valve 122b. That is, as shown in FIG. 8, while continuing the flow of the inspection gas, the filter mechanism 121b operates in conjunction with the closing operation of the on-off valve 122b, and switches the filter 125b to the use position. Thereby, the flow of foreign matter into the on-off valve 122b is prevented. After a predetermined time has elapsed since the position of the filter 125b has been set, the closing of the on-off valve 122b is completed as shown in FIG.

  In this state, the upstream side open / close valve 122a is in the initial open state, and the upstream side filter mechanism 121a has the filter 125a set to the initial non-use position. Note that when the downstream on-off valve 122b is closed, the upstream filter 125a may also be set at the use position. In this case, when the flow of the inspection gas is continued after the downstream opening / closing valve 122b is closed, as shown in FIG. 10, the upstream filter 125a is opened while the upstream opening / closing valve 122a is opened. It is preferable to set to a non-use position. Thus, the inspection gas can be introduced into the inspection object 111 without being affected by the pressure loss due to the upstream filter 125a as much as possible. Note that the position of the downstream filter 125b may remain at the use position or may be set to a non-use position.

  After the setting as described above (after the downstream on-off valve 122b is closed), when it is confirmed that the pressure values detected by the two pressure gauges 123a and 123b are equal, the upstream on-off valve 122a is closed. To do. As a result, the device under test 111 is placed in an airtight state. When the upstream side opening / closing valve 122a is closed, if the upstream side filter 125a is in a non-use position, the filter 125a is used in conjunction with the closing operation of the opening / closing valve 122a. It is preferable to set to. Finally, the original pressure on-off valve and the like are closed. At this time, the pressure value of each part is measured by the two pressure gauges 123a and 123b. Here, the upstream pressure value is PD1, and the downstream pressure value is PD2.

  Then, this state is left, and after a predetermined time has elapsed, the pressure values of the respective parts are again measured by the two pressure gauges 123a and 123b. Here, the upstream pressure value is PL1, and the downstream pressure value is PL2. The evaluation of the leak characteristics of the device under test 111 is performed based on the measurement results of the pressure values of the pressure gauges 123a and 123b. For example, when there is no leak in the device under test 111, PD1 = PL1 and PD2 = PL2.

  However, if there is any leak on one or both of the inlet port side and the outlet port side of the device under test 111, there is a difference in pressure value between PD1 and PL1 and / or between PD2 and PL2. Will occur. In this way, it is possible to determine the presence or absence of leakage from the device under test 111 based on the pressure change in the airtight space where the device under test 111 is placed. The measurement result of each pressure value may be taken into a computer, and the presence or absence of a leak may be determined by the computer. The pressure values of the pressure gauges 123a and 123b are made visible so that the operator can You may determine the presence or absence of a leak based on a measurement result.

  As described above, according to the leak inspection apparatus 110 of the present embodiment, the filter mechanism 121b operates in conjunction with the valve closing operation of the on-off valve 122b on the downstream side of the device under test 111, and the filter 125b is in the use position. After that, the on-off valve 122b closes the downstream passage 112b. As a result, it is possible to prevent foreign matter from adhering to the on-off valve 122b during the valve-closing operation process, and thus it is possible to suitably prevent malfunction of the on-off valve 122b.

  Therefore, since leakage from the on-off valves 122a and 122b can be prevented, the leakage inspection of the device under test 111 can be performed accurately. Further, in the initial stage of the leak inspection, when the inspection gas is allowed to pass through the inspection object 111, the filters 125a and 125b are set to the non-use positions in conjunction with the opening operation of the on-off valves 122a and 122b. Therefore, it is possible to flow the inspection gas without being affected by the pressure loss caused by the filters 125a and 125b.

  In the above description, the fuel cell is taken as an example of the inspected object 111, but the inspected object 111 is not limited to this. For example, various pipe elements such as the pressure regulating valve 32 and the shut valve (48, 52) in the fuel cell system 1 of the first embodiment can be used as a test object to perform a leak test. Further, the present invention is not limited to the case where the upstream side passage 112a and the downstream side passage 112b are directly connected to the device under test 111 itself as in the fuel cell. For example, like the container described in Patent Document 1, a container to be inspected 111 is accommodated in an inspection container that forms a sealed space, and the upstream passage 112a and the downstream passage 112b are connected to the inspection container. May be. In addition, although inert gas etc. were used as test | inspection gas, instead of this, you may perform a leak test | inspection by making the airtight space defined by the leak test | inspection apparatus 110 into a vacuum.

<Third Embodiment>
Next, a modified example of the on-off valve and the filter mechanism will be described with reference to FIG. The assembly of the on-off valve 151 and the filter mechanism 152 is configured such that the on-off valve 151 and the filter mechanism 152 are mechanically interlocked, and the on-off valve 44 and the filter mechanism 43 of the first embodiment, or the second embodiment. It can be applied to the on-off valves 122a and 122b and the filter mechanisms 121a and 121b on the upstream side or the downstream side of the embodiment.

  As shown in FIG. 11, the on-off valve 151 has an angle valve structure as a whole, and is provided in a passage 153 on the downstream side of the filter mechanism 152. The on-off valve 151 is configured such that a valve body 162 can be attached to and detached from a valve seat 161 formed on the inner wall of the pipe.

  The filter mechanism 152 includes a filter 171 disposed coaxially with the valve body 162 of the on-off valve 151, and a filter operating mechanism 172 that sets the position of the filter 171. The filter 171 includes a filter element 181 and a seal portion 183 that can be attached to and detached from the sheet portion 182 formed on the inner wall of the tube, as in the above embodiment. The filter operating mechanism 172 includes a rod 191 connected to the center of the filter element 181 and an actuator 192 that moves the rod 191 back and forth in the axial direction.

  Here, the valve body 162 has a rod 191 inserted from the center thereof, and is configured to be movable relative to the rod 191 while maintaining sealing performance with the rod 191. The valve body 162 and the filter 171 are connected to each other via, for example, a tension spring 195 in the axial direction of the rod 191. With such a configuration, the opening and closing of the on-off valve 151 is performed via the tension spring 195 when the filter operating mechanism 172 operates.

  Specifically, when the on-off valve 151 is opened, the rod 191 is retracted by driving the actuator 192 and the filter 171 is separated from the seat portion 182, but at this time, the valve body 162 is connected via the tension spring 195. Is also separated from the valve seat 161. On the other hand, when the on-off valve 151 is closed, the rod 191 is extended by driving the actuator 192 and the filter 171 contacts the seat portion 182. At this time, the valve body 162 is also connected to the valve seat 161 via the tension spring 195. It moves so that it touches. In this case, the contact of the valve body 162 with the valve seat 161 is delayed from the contact of the filter 171 with the seat portion 182 due to the tension spring 195.

  As described above, according to this embodiment, the filter 171 that operates in conjunction with the closing operation of the on-off valve 151 is mechanically moved to the use position (closed state) before the on-off valve 151 is closed. Will be set. As a result, similarly to the above-described embodiments, it is possible to suitably prevent malfunction of the on-off valve 151 due to the valve closing operation process. It goes without saying that other structures can be applied to the interlocking mechanism between the on-off valve 151 and the filter 171. Further, as described in the first embodiment, various filters 171 having different degrees of filtration can be exchanged or used simultaneously.

It is a block diagram which shows the structure of the fuel cell system which concerns on 1st Embodiment. It is sectional drawing which shows typically the on-off valve and foreign material capture | acquisition means of 1st Embodiment. It is sectional drawing which shows typically the on-off valve and foreign material capture | acquisition means of 1st Embodiment. It is sectional drawing which shows typically the on-off valve and foreign material capture | acquisition means of 1st Embodiment. It is a block diagram which shows the structure of the principal part of the leak inspection apparatus which concerns on 2nd Embodiment. It is a perspective view which shows typically the external appearance of the fuel cell which is a to-be-inspected object. It is sectional drawing which shows typically the on-off valve and foreign material capture | acquisition means of the downstream of 2nd Embodiment. It is sectional drawing which shows typically the on-off valve and foreign material capture | acquisition means of the downstream of 2nd Embodiment. It is sectional drawing which shows typically the on-off valve and foreign material capture | acquisition means of the downstream of 2nd Embodiment. It is sectional drawing which shows typically the on-off valve and foreign material capture | acquisition means of the upstream of 2nd Embodiment. It is sectional drawing which shows typically the on-off valve and foreign material capture | acquisition means of 3rd Embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Fuel cell system, 2 Fuel cell, 3 Piping line, 41 Supply passage (passage), 43 Filter mechanism (foreign material capture means), 44 On-off valve, 91 filter, 110 Leak inspection apparatus, 111 Inspected object, 112a Upstream passage 112b Downstream passage, 121a filter mechanism, 121b filter mechanism, 122a on-off valve, 122b on-off valve, 125a filter, 125b filter, 151 on-off valve, 152 filter mechanism, 171 filter

Claims (13)

In a fuel cell system having an on-off valve that opens and closes a passage of a piping line,
The fuel cell system, wherein the piping line on the upstream side of the on-off valve is provided with foreign matter capturing means that operates in conjunction with the closing operation of the on-off valve and captures foreign matter flowing through the passage. The foreign matter capturing means is composed of a filter mechanism having a filter facing the passage,
The fuel cell system according to claim 1, wherein the filter mechanism is configured to be able to set a position of the filter with respect to the passage in conjunction with an opening / closing operation of the opening / closing valve.   3. The fuel cell system according to claim 2, wherein the filter mechanism switches between a use position and a non-use position of the filter with respect to the passage in conjunction with each opening and closing operation of the on-off valve.   The fuel cell system according to claim 3, wherein the filter mechanism switches the filter to a use position with respect to the passage in preference to the on-off valve closing the passage.   The fuel cell system according to any one of claims 2 to 4, wherein a plurality of types of filters having different filtration degrees are prepared. In the leak inspection apparatus comprising the on-off valve for opening and closing the passage connected to the downstream side of the object to be inspected, and performing the leak inspection of the object to be inspected by closing the on-off valve and making it airtight,
The leak inspection apparatus, wherein the passage on the upstream side of the on-off valve is provided with foreign matter capturing means that operates in conjunction with the closing operation of the on-off valve and captures the foreign matter flowing through the passage. The foreign matter capturing means is composed of a filter mechanism having a filter facing the passage,
The leak inspection apparatus according to claim 6, wherein the filter mechanism is configured to be able to set a position of the filter with respect to the passage in conjunction with an opening / closing operation of the opening / closing valve.   The leak inspection apparatus according to claim 7, wherein the filter mechanism switches between a use position and a non-use position of the filter with respect to the passage in conjunction with each opening and closing operation of the on-off valve.   The leak inspection apparatus according to claim 8, wherein the filter mechanism switches the filter to a use position with respect to the passage in preference to the on-off valve closing the passage.   The leak inspection apparatus according to claim 9, wherein the filter mechanism switches the filter to a non-use position with respect to the passage after the on-off valve is closed.   The leak inspection apparatus according to any one of claims 6 to 10, wherein a plurality of types of filters having different filtration degrees are prepared. Connecting the passage having the on-off valve to the downstream side of the object to be inspected, and making the portion of the passage between the on-off valve and the object to be inspected to be able to capture foreign matter;
And a step of closing the open / close valve after the step to bring the device under test into an airtight state, and performing a leak test of the device under test based on a pressure change in the airtight space.   A fuel cell that has been subjected to leak inspection as the object to be inspected by the leak inspection apparatus according to any one of claims 6 to 11 or the leak inspection method according to claim 12.

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