Hydrogen concentration measuring element and hydrogen concentration measuring device

Abstract

According to one embodiment, a hydrogen concentration measuring element (100, 100a, 100b) comprises: a wire-shaped detection part (110) comprising a first metal wire (111) whose electrical resistance value is changed by hydrogen absorption and a first protective coating layer (112) having hydrogen permeability and covering the first metal wire (111); a plate-shaped fixing part (130); two first terminal parts (151, 152) each provided on one of two surfaces of the fixing part (130); and a plurality of guides (140) which are provided on at least one surface of the fixing part (130) to protrude from the surface and enable the detection part (110) to be laid between the two first terminals while changing a direction. Figure for abstract: Fig 2

Description

Title of the invention: Hydrogen concentration measuring element and hydrogen concentration measuring apparatus FIELD OF THE INVENTION

[0001] Embodiments of the present invention relate to a hydrogen concentration measuring element and a hydrogen concentration measuring apparatus comprising the same.

[0002] CONTEXT OF THE INVENTION

[0003] Typical hydrogen concentration measuring devices include those using catalytic combustion type and semiconductor type measuring methods.

[0004] Technologies for the catalytic combustion type include that which uses combustion heat on a catalyst that promotes the combustion of hydrogen and oxygen, and detects the hydrogen concentration on the basis of a change in resistance value occurring in a resistance measuring device (thermistor) caused by the change in temperature due to the combustion heat. Technologies for the semiconductor type include that which uses a change in electrical resistance value due to a change in carrier density on the surface of a semiconductor, such as tin oxide, caused by the absorption of a reducing gas.

[0005] Furthermore, hydrogen concentration measurement technologies for nuclear power plants include a technology for determining the volume expansion of palladium due to its absorption of hydrogen and for determining a change in scattered light when light having a specific wavelength penetrates through an optical fiber and a technology for determining an electrical resistance value of a hydrogen-absorbing material.

[0006] A hydrogen concentration measuring apparatus for determining the electrical resistance value of the hydrogen absorbing material comprises: a hydrogen concentration measuring element including a detecting part in which a metal wire acting as the hydrogen absorbing material is covered with a protective coating layer having hydrogen permeability and a fixing part around which the detecting part is wound; and a calculating device that calculates the hydrogen concentration from the electrical resistance value in the hydrogen concentration measuring element.

[0007] PRIOR ART DOCUMENT

[0008] PATENT DOCUMENT

[0009] Patent Document 1: Japanese Patent No. 6,585,463 Summary of the invention

[0010] PROBLEMS TO BE SOLVED BY THE INVENTION

[0011] In the above-described hydrogen concentration measuring apparatus, the metal wire elongates / contracts by thermal expansion. Therefore, when the temperature increases / decreases during shipping tests of the hydrogen concentration measuring element or during use thereof, friction occurs in a contact portion between the protective coating layer covering the metal wire and the peripheral members, resulting in the peeling of the protective coating layer. In particular, in the structure where the detection portion is wound around the fixing portion, a portion of the detection portion that contacts and rubs against the fixing portion changes randomly. Therefore, a peeled area of ​​its film enlarges when the temperature repeatedly increases and decreases, resulting in the deterioration of hydrogen detection performance.Furthermore, this leads to a problem of increasing variation between products.

[0012] An object of the present invention is to provide a hydrogen concentration measuring element and a hydrogen concentration measuring apparatus capable of suppressing deterioration in hydrogen detection performance. SOLUTION TO THE PROBLEM

[0013] According to one aspect of the present invention, there is provided a hydrogen concentration measuring element comprising: a wire-shaped detection part including a first metal wire whose electrical resistance value is changed by hydrogen absorption and a first protective coating layer having hydrogen permeability and covering the first metal wire; a plate-shaped fixing part; two first terminal parts each provided on one of two surfaces of the fixing part; and a plurality of guides which are provided on at least one surface of the fixing part to protrude from the surface and enable the detection part to be laid between the two first terminals while changing a direction. Brief description of the drawings

[0014] [Fig. 1] is a block diagram illustrating the configuration of a hydrogen concentration measuring apparatus according to one embodiment.

[0015] [Fig.2] is a perspective view illustrating the structure of the hydrogen concentration measuring element in the hydrogen concentration measuring apparatus according to the first embodiment.

[0016] [Fig.3] is a vertical sectional view illustrating the structure of the detection portion in the hydrogen concentration measuring element of the hydrogen concentration measuring apparatus according to the first embodiment.

[0017] [Fig.4] is a cross-sectional view illustrating the structure of the detection portion in the hydrogen concentration measuring element of the hydrogen concentration measuring apparatus according to the first embodiment.

[0018] [Fig.5] is a perspective view illustrating a first example of modification of the guide in the hydrogen concentration measuring element of the hydrogen concentration measuring apparatus according to the first embodiment.

[0019] [Fig.6] is a perspective view illustrating a second example of modification of the guide in the hydrogen concentration measuring element of the hydrogen concentration measuring apparatus according to the first embodiment.

[0020] [Fig.7] is a perspective view illustrating a third example of modification of the guide in the hydrogen concentration measuring element of the hydrogen concentration measuring apparatus according to the first embodiment.

[0021] [Fig.8] is a perspective view illustrating a fourth example of modification of the guide in the hydrogen concentration measuring element of the hydrogen concentration measuring apparatus according to the first embodiment.

[0022] [Fig.9] is a perspective view illustrating a fifth example of modification of the guide in the hydrogen concentration measuring element of the hydrogen concentration measuring apparatus according to the first embodiment.

[0023] [Fig. 10] is a perspective view illustrating the structure of a hydrogen concentration measuring element in a hydrogen concentration measuring apparatus according to a second embodiment.

[0024] [Fig. 11] is a vertical sectional view illustrating the structure of the reference detection portion in the hydrogen concentration measuring element of the hydrogen concentration measuring apparatus according to the second embodiment.

[0025] [Fig. 12] is a cross-sectional view illustrating the structure of the reference detection portion in the hydrogen concentration measuring element of the hydrogen concentration measuring apparatus according to the second embodiment.

[0026] [Fig. 13] is a front view illustrating the structure of the hydrogen concentration measuring element in the hydrogen concentration measuring apparatus according to the second embodiment.

[0027] [Fig. 14] is a front view illustrating the structure of a hydrogen concentration measuring element in a hydrogen concentration measuring apparatus according to a third embodiment.

[0028] [Fig. 15] is a sectional view taken in the direction of arrow AA in [Fig. 14], illustrating the structure of the hydrogen concentration measuring element 100b in the hydrogen concentration measuring apparatus according to the third embodiment.

[0029] [Fig. 16] is a side view observed in the direction of arrow BB, illustrating the structure of the hydrogen concentration measuring element in the hydrogen concentration measuring apparatus according to the third embodiment.

[0030] Hereinafter, a hydrogen concentration measuring element and a hydrogen concentration measuring apparatus according to embodiments of the present invention will be described with reference to the accompanying drawings. The same reference numerals are given to the same or similar parts, and repetition of the description will be omitted. DETAILED DESCRIPTION [0031 ] [First embodiment]

[0032] [Fig. 1] is a block diagram illustrating the configuration of a hydrogen concentration measuring apparatus 10 according to one embodiment. [Fig. 1] illustrates an example in which a measurement target of the hydrogen concentration measuring apparatus 10 is an atmosphere in a nuclear reactor containment vessel 1 of nuclear reactor facilities (not shown). The nuclear reactor containment vessel 1 is an enclosure for housing a nuclear reactor containment vessel (not shown). It should be noted that the measurement target of the hydrogen concentration measuring apparatus 10 is not limited to the atmosphere in the nuclear reactor containment vessel 1 and may be other targets such as an atmosphere whose hydrogen concentration is to be measured, for example, in hydrogen production facilities or hydrogen supply facilities.

[0033] The hydrogen concentration measuring apparatus 10 comprises a hydrogen concentration measuring element 100, a resistor 31, a connection line 32 and an information processing unit 33.

[0034] The hydrogen concentration measuring element 100 comprises a detection part 110 (see [Fig. 2] which will be described later) which is a metal wire having a hydrogen absorption capacity and whose electrical resistance value is changed by the absorption of hydrogen, and which is a part which detects hydrogen. The details of the hydrogen concentration measuring element 100 will be described later with reference to FIGS. 2 to 9.

[0035] The resistor 31 connects to the detection part 110 via the connecting line 32. The electrical resistance value of the sensing part 110 is measured when a current flows through the resistor 31. As the resistor 31, a known resistor is used. In the case where the resistor 31 uses a measurement method other than a four-terminal method, for example, a two-terminal method or a Wheatstone bridge, a resistor suitable for the measurement method is used.

[0036] The information processing unit 33 comprises a CPU (Central Processing Unit) and a memory. The information processing unit 33 calculates the hydrogen concentration based on the electrical resistance value of the detection part 110 measured using the resistor 31. That is, it uses a phenomenon that the electrical resistance value of the detection part 110 increases upon absorption of hydrogen. Based on a hydrogen concentration-electrical resistance value correlation formula obtained in advance and the electrical resistance value of the detection part 110 measured by means of the resistor 31, the information processing unit 33 sequentially calculates the hydrogen concentration.

[0037] [Fig.2] is a perspective view illustrating the structure of the hydrogen concentration measuring element 100 in the hydrogen concentration measuring apparatus 10 according to the first embodiment.

[0038] The hydrogen concentration measuring element 100 comprises the wire-shaped detection part 110, a fixing part 130 which is a rectangular flat plate, a plurality of guides 140 provided on one surface of the fixing part 130, and terminal parts 151, 152 in the form of two first terminal parts arranged on the same plane as that where the guides 140 are arranged. If necessary, the hydrogen concentration measuring element 100 may have a protective plate 160 which protects the detection part 110 from the outside.

[0039] It should be noted that the planar shape of the fixing portion 130 is not limited to the rectangular shape, even though [Fig. 2] illustrates the case where it is rectangular. The shape of the fixing portion 130 may be appropriately decided according to the spatial restriction conditions, a state, etc. of an installation place of the hydrogen concentration measuring element 100. As long as it is ensured that the detection portion 110 can be laid without contacting with others, the fixing portion 130 may have a non-coplanar shape, such as a shape partially having a curved surface. Furthermore, the fixing portion 130 itself may have a hole through which the measurement target gas can flow.

[0040] The detection portion 110 is placed between the terminal portion 151 and the terminal portion 152. The detection portion 110 will be described in detail below with reference to Figures 3 and 4.

[0041] The guides 140 protrude from the fixing portion 130 and are supporting members which support a part of the detection portion 110 and where a wiring direction of the detection portion 110 can be changed when the wire-shaped detection portion 110 is wired and laid.

[0042] The guides 140 are arranged at positions where the detection portion 110 changes direction to meander between the terminal portion 151 and the terminal portion 152. The detection portion 110 can slide relative to the guides 140. As illustrated in [Fig. 2], on one side portion 132a on the side of the fixing portion 130, four of the plurality of guides 140 are arranged at intervals along the side portion 132a. Furthermore, on the other side portion 132b on the side opposite to the side portion 132a of the fixing portion 130, three of the guides 140 are arranged at intervals along the side portion 132b. The guides 140 are fixed to the fixing portion 130 by welding, screwing, or the like.

[0043] Although [Fig. 2] illustrates the case where the number of guides 140 is four and three for example, the number is not limited to these and may be greater or less than these. Furthermore, although the case where the number on one side is greater than one is illustrated as an example, the numbers on one side and the other side may be equal.

[0044] The positional relationship between the guides 140 arranged on the side of the lateral portion 132a and the guides 140 on the side of the lateral portion 132b is as follows in the example illustrated in [Fig.2].

[0045] More specifically, firstly, the intervals between the guides 140 arranged on the side of the lateral portion 132a and the intervals between the guides 140 arranged on the side of the lateral portion 132b are equal. Secondly, the guides 140 arranged on the side of the lateral portion 132b are each arranged at a position such that its plane center is equidistant from the plane centers of the two guides 140 among the guides 140 arranged on the side of the lateral portion 132a. However, this is not limiting and, for example, one of the two aforementioned guides 140 may deviate in the longitudinal direction of the arrangement.

[0046] In the example described above, the guides 140 are arranged in two rows parallel to each other, and the detection portion 110 is sequentially arranged between the guides 140 of the two rows facing each other. However, the arrangement of the guides 140 is not limited to this. Another adoptable example is that the guides 140 are arranged in a spiral and the detection portion 110 is laid in the circumferential direction to extend radially outward from the center or in the opposite direction. In this case, the laid detection portion 110 may have a circular or polygonal shape, or may change direction at right angles at the guides 140.

[0047] The guides 140 each have a groove 141 formed as a guide portion in the middle of its column in an axial direction. The detection portion 110 changes direction along a portion of the surfaces of the grooves 141. The sensing portion 110 and the surfaces of the grooves 141 can slide relative to each other. In the guides 140, portions closer to the fixing portion 130 than the grooves 141 act as internal stops 142 which are anti-contact devices that prevent the sensing portion 110 from coming into contact with the fixing portion 130. In the guides 140, portions on a side further outward than the grooves 141 act as external stops 143 that prevent the sensing portion 110 from coming loose. The external stops 143 are stopping aids that prevent the sensing portion 110 from coming loose from the guides 140 in the direction in which the guides 140 protrude from the fixing portion 130.The outer stops 143 as stopping aids are each provided by a portion extending in a direction opposite to a direction of the resultant tension force that is generated on a plane perpendicular to the protrusion direction of the guide 140 from the fixing portion 130 when the detection portion 110 is caught by the guide 140, such as, for example, the outer stop 143 which is the portion on the side further outward than the groove 141 in the guide 140 in this embodiment. In the case where the cover plate 160 is provided, the outer stops 143 have the function of preventing the detection portion 110 from coming into contact with the cover plate 160.

[0048] At least the surfaces of the parts that come into contact with the detection part 110, for example the surfaces of the grooves 141, may be covered with electrical insulators.

[0049] The protective plate 160 has substantially the same shape and size as those of the fixing portion 130. The protective plate 160 is disposed opposite the fixing portion 130 through the guides 140 to face the fixing portion 130. The protective plate 160 has a plurality of vents 161 arranged two-dimensionally at intervals. The vents 161 may be any as long as they allow the passage of hydrogen molecules, and they may be holes of a porous body, or the like, for example, but from the viewpoint of real-time detection of a hydrogen concentration, the vents 161 preferably allow the permeation of such a large amount of hydrogen molecules per unit time. The protective plate 160 is joined to some of the plurality of guides 140 by screwing, welding, or the like, but this is not limiting.For example, the protective plate 160 may be attached to the attachment portion 130 by a spacer having the same height as that of the guides 140.

[0050] [Fig.3] is a vertical sectional view illustrating the structure of the detection portion 110 in the hydrogen concentration measuring element 100 of the hydrogen concentration measuring apparatus 10 according to the first embodiment, and [Fig.4] is a cross-sectional view thereof. The detection part 110 will be described in detail below.

[0051] The sensing portion 110 has a metal wire 111 and a protective coating layer 112 provided on the outer side of the metal wire 111. The metal wire 111 acts as the first metal wire and the protective coating layer 112 acts as the first protective coating layer.

[0052] The metal wire 111 contains at least one of palladium and niobium and has a hydrogen absorption capacity. The diameter of the metal wire 111 having the hydrogen absorption capacity is not limited and is preferably greater than or equal to about 1 μm and less than or equal to about 1000 μm. This is because if the metal wire 111 has a diameter less than 1 μm, there is a high risk of it breaking due to its tension, and if the metal wire 111 has a diameter greater than 1000 μm, its resistance value per unit length is low, resulting in a decrease in hydrogen detection performance.

[0053] The protective coating layer 112 contains at least one of an oxide, a nitride, and a carbide of silicon or aluminum, and is formed of an inorganic substance allowing selective permeation by hydrogen. The thickness of the protective coating layer 112 is preferably 5 nm or more and 200 nm or less. The protective coating layer 112 having a thickness of 5 nm or more has a remarkable effect of preventing the progress of a side reaction attributable to chemical species from an external gas layer of oxygen, iodine, or the like. The protective coating layer 112 having a thickness of 200 nm or less has excellent hydrogen permeability.

[0054] The detection part 110 is here formed by applying or vapor deposition of the protective coating layer 112 on the metal wire 111 having the hydrogen absorption capability. As the application or vapor deposition method, a typical method is used, such as CVD (chemical vapor deposition), PVD (physical vapor deposition), a sol-gel method, or an impregnation method. Here, the CVD (chemical vapor deposition) includes atomic layer deposition having a high vapor deposition coating capability, even if its target is a three-dimensional object. Furthermore, the detection part 110 formed by any of these methods is used after heat treatment at a temperature of 350°C or higher and 500°C or lower.

[0055] Figures 5 to 9 are perspective views illustrating examples of modification of the guide in the hydrogen concentration measuring element of the apparatus of hydrogen concentration measurement according to the first embodiment, [Fig.5] illustrating a first example of modification, [Fig.6] a second example of modification, [Fig.7] a third example of modification, [Fig.8] a fourth example of modification, and [Fig.9] a fifth example of modification.

[0056] A guide 140a according to the first modification example illustrated in [Fig. 5] has annular elements fixed to both axial ends of its column. A guide 140b according to the second modification example illustrated in [Fig. 6] has, as a guide part, a groove 141b whose section in the axial direction is curved, unlike the guide 140 which has, as a guide part, the groove 141 whose section in the axial direction is rectangular. A guide 140c according to the third modification example illustrated in [Fig. 7] is composed of two frustoconical elements whose small diameter sides are connected in the axial direction. Alternatively, the guide 140c may be formed from a column in this shape by cutting.

[0057] A guide 140d according to the fourth modification example shown in [Fig. 8] is cut from a column so that its side surface, as a guide portion, is fully curved in section in the axial direction. A guide 140e according to the fifth modification example shown in [Fig. 9] is formed of a bent bar-shaped member 145e. On its inner side, a recess 141e is formed as a guide portion. The detection portion 110 is capable of changing its direction by sliding on the recess 141e.

[0058] It should be noted that some or all of the guides 140 and the guides 140a, 140b, 140c, 140d and 140e according to the modification examples described above may be present in combination. In all of the modification examples in FIGS. 5 to 9, the guides 140a, 140b, 140c, 140d, and 140e have portions extending in the direction opposite to the direction of the resultant force of the tension that is generated on planes perpendicular to the direction of protrusion of the guides 140a to 140e from the attachment portion 130 when the detection portion 110 is caught by the guides 140a to 140e, and these portions act as stopping aids that prevent the detection portion 110 from detaching in the direction of protrusion of the guides 140a to 140e from the attachment portion 130.

[0059] As described above, the guides 140 or any of the modification examples thereof are arranged on the plate-shaped fixing part 130 so as to protrude from the fixing part 130, and this allows the detection part 110 to change direction by sliding at the guides 140 and to be laid along the fixing part 130 with a required length. It is also possible to lay the detection part 110 while preventing the detection part 110 from detaching from the fixing part 130, by preventing the part from detection portion 110 from contacting the fixing portion 130, and preventing portions of the detection portion 110 from contacting each other.

[0060] According to this embodiment, the regions against which the protective coating layer 112 of the detection part 110 rubs are only the guide parts, and the peeled area of ​​the protective coating layer 112 enlarges less. Therefore, it is possible to reduce the deterioration of the detection performance of the hydrogen concentration measuring apparatus 10 and to reduce the variations between products. In addition, the plate shape of the fixing part 130 contributes to the thinning of the entire hydrogen concentration measuring element 100, which has the effect of arrangement merit. In addition, due to the plate shape of the fixing part 130, a measure for protecting the detection part 110 during transportation may only be to cover the surface of the fixing part 130 with a temporary plate or with the protective plate 160 if the protective plate 160 is provided.

[0061] [Second embodiment]

[0062] [Fig. 10] is a perspective view illustrating the structure of a hydrogen concentration measuring element 100a in a hydrogen concentration measuring apparatus 10a according to a second embodiment.

[0063] The second embodiment is a modification of the first embodiment. The hydrogen concentration measuring element 100a has a wire-shaped reference detection part 120 in addition to a detection part 110. The reference detection part 120 is disposed on the same surface of a fixing part 130 where the detection part 110 is disposed. Therefore, the hydrogen concentration measuring element 100a has a plurality of first guides 140f and a plurality of second guides 140s, i.e., two types of guides provided with guide parts having different diameters. It also has terminal parts 151a, 152a as two first terminal parts for the detection part 110 and terminal parts 151b, 152b as two second terminal parts for the reference detection part 120.Each of the two second terminal parts is adjacent to each of the first terminals.

[0064] The first guides 140f and the second guides 140s each have the same shape as that of any of the guides 140 described in the first embodiment and the guides 140a, 140b, 140c, 140d, 140e according to the modification examples. Furthermore, these shapes may be present in combination as shapes of the first guides 140f and the second guides 140s.

[0065] The height in the axial direction of the first guides 140f and the height in the axial direction of the second guides 140s are equal. The diameter of the parts of guide of the first guides 140f is greater than the diameter of the guide portions of the second guides 140s. The arrangement of the first guides 140f and the second guides 140s will be described below with reference to [Fig. 13]. It should be noted that the height in the axial direction of the first guides 140f and the height in the axial direction of the second guides 140s may be different, although the height in the axial direction of the first guides 140f and the height in the axial direction of the second guides 140s are equal in this embodiment.

[0066] [Fig. 11] is a vertical sectional view illustrating the structure of the reference detection portion 120 in the hydrogen concentration measuring element 100a of the hydrogen concentration measuring apparatus 10a according to the second embodiment. [Fig. 12] is a cross-sectional view illustrating the structure of the reference detection portion 120 in the hydrogen concentration measuring element 100a of the hydrogen concentration measuring apparatus 10a according to the second embodiment.

[0067] The reference sensing portion 120 comprises a metal wire 121 and a protective coating layer 122 covering the radially outer surface of the metal wire 121. The metal wire 121 acts as a second metal wire and the protective coating layer 122 acts as a second protective coating layer.

[0068] The metal wire 121 is made of a material whose electrical resistance value varies with a change in temperature, such as platinum used in a resistance temperature detector, and has no hydrogen absorption capacity. The diameter of the metal wire 121 is greater than or equal to about 1 μm and less than or equal to about 1000 μm, like the diameter of the metal wire 111 of the sensing portion 110. The protective coating layer 122 contains at least one of an oxide, a nitride, and a silicon or aluminum carbide, and is made of an inorganic substance allowing the selective permeation of hydrogen, like the protective coating layer 112 of the sensing portion 110. The protective coating layer 122 preferably has a thickness greater than or equal to 5 nm and less than or equal to 200 nm, like the protective coating layer 112 of the sensing portion 110.

[0069] The information processing unit 33 calculates the temperature in the vicinity of the metal wire 121 on the basis of the electrical resistance value of the metal wire 121 of the reference detection part 120. The information processing unit 33 further removes a component attributable to the temperature from the electrical resistance value measured in the metal wire 111 of the detection part 110 to separate a component attributable to the absorption of hydrogen and calculates the hydrogen concentration.

[0070] [Fig. 13] is a front view illustrating the structure of the hydrogen concentration measuring element 100a in the hydrogen concentration measuring apparatus 10a according to the second embodiment. It should be noted that the illustration of a protective plate 160 is omitted.

[0071] The first guides 140f and the second guides 140s are arranged as follows.

[0072] More specifically, firstly, on a side portion 132a on the side of the fixing portion 130, four of the first guides 140f having a larger diameter are arranged at intervals along the side portion 132a, as in the first embodiment. Further, on a side portion 132b on the side opposite the side portion 132a of the fixing portion 130, three of the first guides 140f are arranged at intervals along the side portion 132b.

[0073] Second, on the inner side of the first four guides 140f arranged along the side portion 132a, the second guides 140s of smaller diameter are arranged. Furthermore, the second guides 140s are arranged on the inner side of the first three guides 140f arranged along the side portion 132b.

[0074] Here, the inner side refers to a side toward a region sandwiched by the first guides 140f arranged along the side portion 132a and the first guides 140f arranged along the side portion 132b. It should be noted that the aforementioned number of the guides illustrated in [Fig. 10] and [Fig. 13] are only examples and the numbers are not limited thereto as in the first embodiment.

[0075] By the arrangement described above, the detection portion 110 extends from the terminal portion 151a, passes through the first guide 140f on the side portion 132a side, the second guide 140s on the side portion 132b side, the first guide 140f on the side portion 132a side, and the second guide 140s on the side portion 132b side several times, and then reaches the terminal portion 152a.

[0076] The reference detection portion 120 extends from the terminal portion 151b, passes through the second guide 140s on the side portion 132a side, the first guide 140f on the side portion 132b side, the second guide 140s on the side portion 132a side, and the first guide 140f on the side portion 132b side several times, and then reaches the terminal portion 152b.

[0077] As described above, as in the first embodiment, the detection part 110 and the reference detection part 120 are capable of changing by sliding their directions on the guide parts along the surface of the fixing part 130, and it is also possible to lay the detection part 110 and the reference detection part 120 with a required length while preventing the detection part 110 and the reference detection part 120 from contacting the fixing part 130 and the protective plate 160, and preventing the detection part 110 and the reference detection part 120 from contacting each other. the other.

[0078] Furthermore, as in the first embodiment, the peeled areas of the protective coating layers 112, 122 enlarge less and, therefore, it is possible to reduce the deterioration of the detection performance of the hydrogen concentration measuring apparatus 10a and to reduce the variations between the products. Furthermore, the thinning of the entire hydrogen concentration measuring element 100a is achieved.

[0079] [Third embodiment]

[0080] [Fig. 14] is a front view illustrating the structure of a hydrogen concentration measuring element 100b in a hydrogen concentration measuring apparatus 10 according to a third embodiment. [Fig. 15] is a sectional view viewed in the direction of arrow AA in [Fig. 14], illustrating the structure of the hydrogen concentration measuring element 100b in the hydrogen concentration measuring apparatus 10 according to the third embodiment. [Fig. 16] is a side view viewed in the direction of arrow BB in [Fig. 14], illustrating the structure of the hydrogen concentration measuring element 100b in the hydrogen concentration measuring apparatus 10 according to the third embodiment.

[0081] The present embodiment is a modification of the first embodiment. As illustrated in [Fig. 15] and [Fig. 16], guides 140 are provided on both surfaces of a fixing portion 130. Furthermore, as illustrated in [Fig. 15] and [Fig. 16], a terminal portion 151 and a terminal portion 152 are provided on opposite surfaces of the fixing portion 130. Therefore, a range where the detection portion 110 is laid extends from one surface to the other surface of the fixing portion 130.

[0082] The arrangement of the guides 140 and the arrangement of the detection part 110 on these surfaces are the same as those of the first embodiment.

[0083] A through portion 170 is formed to allow the detection portion 110 to pass from a first surface 130f ([Fig. 15]) to a second surface 130s ([Fig. 15]) of the fixing portion 130. In more detail, as illustrated in [Fig. 15] and [Fig. 16], guide through portions 171 are provided at the same position in the first surface 130f and the second surface 130s, with the fixing portion 130 therebetween. The guide through portions 171 each have a curved through hole 171a ([Fig. 14], [Fig. 15]), so that a contact portion of the detection portion 110 with the guide through portion 171 is curved. Furthermore, the fixing portion 130 has, at its portion to which the guide through portions 171 are fixed, a through hole 131 ([Fig.15]), has a diameter larger than that of the curved through holes 171a and smaller than the outer diameter of the guide through portions 171. .

[0084] According to the present embodiment as structured above, it is possible to lay the detection part 110 along both surfaces of the fixing part 130. Therefore, to lay the detection part 110 with the same length, the fixing part 130 only needs to have substantially half an area of ​​that of the first embodiment. Therefore, installation at a location where the area of ​​the fixing part 130 needs to be small due to the arrangement reason becomes easy, which gives more options for the installation location of the fixing part 130.

[0085] According to the embodiments described so far, it is possible to provide a hydrogen concentration measuring element and a hydrogen concentration measuring apparatus which experience less deterioration in hydrogen detection performance.

[0086] [Other embodiments]

[0087] Although embodiments of the present invention have been described, the embodiments have been presented by way of example and are not intended to limit the scope of the inventions. In addition, the features of the second embodiment and the third embodiment may be used in combination. The embodiments may be embodied in various other forms. Various omissions, substitutions, and modifications may be made without departing from the spirit of the invention. The above embodiments and variations thereof fall within the scope and spirit of the invention, and are likewise within the scope of the invention defined in the appended claims and the range of equivalence thereof.

[0088] EXPLANATION OF REFERENCE SYMBOLS

[0089] 1: nuclear reactor containment enclosure, 10, 10a: measuring device hydrogen concentration, 31: resistor, 32: connecting line, 33: information processing unit, 100, 100a, 100b: hydrogen concentration measuring element, 110: detection part, 111: wire, 112: protective coating layer, 120: reference detection part, 121: wire, 122: protective coating layer, 130, 130a: fixing part, 131: through hole, 132a, 132b: side part, 140, 140a, 140b, 140c, 140d, 140e: guide, 140f: first guide, 140s: second guide, 141, 141a, 141b: groove, 141e: recess, 142: stopper internal, 143: external stop, 145e: bent bar-shaped element, 151, 151a, 151b, 152, 152a, 152b: terminal part, 160, 160a: protective plate, 161: vent, 170: through-part, 171: guide through-part, 171a: curved through-hole

Claims

Claims

1. A hydrogen concentration measuring element (100, 100a, 100b) comprising: a wire-shaped detection part (110) comprising a first metal wire (111) whose electrical resistance value is changed by hydrogen absorption and a first protective coating layer (112) having hydrogen permeability and covering the first metal wire (111); a plate-shaped fixing part (130); two first terminal parts (151, 152) each provided on one of two surfaces of the fixing part (130); and a plurality of guides (140) which are provided on at least one surface of the fixing part (130) to protrude from the surface and enable the detection part (110) to be laid between the two first terminal parts (151, 152) while changing a direction.

2. The hydrogen concentration measuring element (100, 100a, 100b) according to claim 1, wherein the plurality of guides (140) are slidable relative to the detection portion (110).

3. A hydrogen concentration measuring element (100, 100a, 100b) according to claim 1 or claim 2, the element (100, 100a, 100b) further comprising a protective plate (160, 160a) facing the fixing portion (130) for covering an outer side of the detection portion (110).

4. The hydrogen concentration measuring element (100, 100a, 100b) according to any one of claims 1 to 3, wherein the plurality of guides (140) each comprise: a contact prevention device that prevents the detection part (110) from coming into contact with the fixing part (130); and a stopping aid that prevents the detection part (110) from leaving in a direction in which the guides (140) protrude from the fixing part (130).

5. The hydrogen concentration measuring element (100, 100a, 100b) according to any one of claims 1 to 4, wherein the plurality of guides (140a, 140b, 140c, 140d) each have a groove-shaped guide portion in the middle in an axial direction of a column of the guide.

6. A hydrogen concentration measuring element (100, 100a, 100b) according to any one of claims 1 to 4, wherein the plurality of guides (140e) each have a shape in which a bar is bent, and have a guide portion formed on an inner side.

7. The hydrogen concentration measuring element (100b) according to any one of claims 1 to 6, wherein: the detection part (110) is laid on a first surface of the fixing part (130) and is further continuously laid on a second surface on a back side of the first surface; and the fixing part (130) has a through part (170) for allowing the detection part (110) to pass through from the first surface to the second surface.

8. A hydrogen concentration measuring element (100, 100a, 100b) according to any one of claims 1 to 7, wherein at least one surface of portions that contacts the detection portion (110) in each of the plurality of guides (140) is an electrical insulator.

9. The hydrogen concentration measuring element (100a) according to any one of claims 1 to 8, further comprising: a wire-shaped reference detection part (120) comprising a second metal wire (121) whose electrical resistance value is changed by a temperature change and a second protective coating layer (122) covering the second metal wire (121); two second terminal parts (151b, 152b) provided adjacent to the first terminal parts (151a, 152a); and a plurality of second guides (140s) which guide the reference detection part (120), wherein: in the second guides (140), the parts which come into contact with the reference detection part (120) have a diameter different from that of the parts which come into contact with the detection part (110) in the guides (140);and the reference detection part (120) is laid along the detection part (110) between the two second terminal parts (151b, 152b) without contacting the detection part (110).;

10. A hydrogen concentration measuring apparatus (10, 10a) comprising: the hydrogen concentration measuring element (100, 100a, 100b) according to any one of claims 1 to 9; and an information processing unit (33) which calculates the hydrogen concentration from the electrical resistance value of the first metal wire (111) of the hydrogen concentration measuring element (100, 100a, 100b).

11. A hydrogen concentration measuring apparatus (10, 10a) according to claim 10, wherein a measurement target is an atmosphere in a nuclear reactor containment vessel (1).

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