JP2009144804A - High-pressure tank - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-pressure tank capable of determining the damage originating from an impact directly, visually, and at low cost. <P>SOLUTION: Several sorts of color emitting films 41 (41a-41c) emitting colors due to an impact given externally are affixed together according to the part on the peripheral area of the high-pressure tank 21. Affixing the films 41 should preferably be done in accordance with the limit strength of the part on the peripheral area of the tank 21. It is also preferable that a colored ink with hue or brightness varying with time be encapsulated in a microcapsule included in the color emitting films 41. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a high-pressure tank. More specifically, the present invention relates to an improvement in the structure of a high-pressure tank used as a fuel tank for vehicles.

  In recent years, much research and development has been conducted on vehicles equipped with fuel cells as power generation devices. As a fuel cell used as a power source of a vehicle or the like, for example, a polymer electrolyte fuel cell is mounted, and a fuel tank for supplying fuel gas (for example, hydrogen gas) to the fuel cell is also mounted. Conventionally, high-pressure hydrogen tanks of about 35 MPa have been used as these fuel tanks, and for example, a plurality of them are mounted in a state where they are arranged in parallel in the front-rear direction of the vehicle.

  For such a high-pressure tank, it is important to have a configuration that can accurately determine how much damage is received, for example, when an impact is applied from the outside during a light vehicle collision. If the degree of damage can be accurately determined, it is possible to more accurately determine the remaining life, such as whether to use the high-pressure tank continuously.

Conventionally, there has been disclosed a high-pressure tank in which a material that can be crushed is disposed on the surface, which is physically changed by an external impact to detect damage received by the high-pressure tank and detect it if abnormal ( For example, see Patent Document 1). Also disclosed is a technique (for example, refer to Patent Document 2) in which damage can be determined by a piezo sensor installed on the surface of a high-pressure tank, and a technique using a G sensor or an AE (acoustic emission) sensor.
JP-A-8-35598 JP 2006-275223 A

  However, although the conventional technique is suitable for detecting an abnormality in the high-pressure tank, there are cases where it is not sufficient in terms of accurately judging the damage received by the impact from the outside. The various sensors described above capture damage indirectly, and are not suitable for obtaining visual and direct determination results.

  Therefore, an object of the present invention is to provide a high-pressure tank having a structure capable of directly and visually determining damage received due to an impact at low cost.

  In order to solve this problem, the present inventor has made various studies. For example, a conventionally used G sensor also outputs a dummy impact that is unrelated to the damage of the high-pressure tank, so that it is difficult to determine a serious damage that affects the remaining life of the high-pressure tank (FIG. 11). reference). In addition, since the AE sensor cannot be detected unless it is turned on at the moment when damage occurs (that requires real-time detection), for example, when mounted on a vehicle, the vehicle is stopped (ignition off). In this case, the AE sensor needs to be energized. Furthermore, for example, a detection device itself using an AE sensor is generally expensive. From these viewpoints, the present inventor who has repeatedly studied new sensing means and the like has obtained new knowledge that leads to the solution of such problems.

  The high-pressure tank according to the present invention has been made based on this finding, and it is said that a plurality of types of color-developing films that are colored by the influence of an external impact are bonded to the outer periphery of the tank according to the outer peripheral part of the tank. Is. In this case, it is preferable that the coloring film is bonded according to the limit strength at the outer periphery of the tank.

  Further, the high-pressure tank according to the present invention is such that a color-developing film that develops color under the influence of an external impact is wound into a plurality of layers when the filament is wound around the outer periphery of the tank. As the coloring film, it is preferable to use a plurality of types of films having different colors at the time of coloring.

  Furthermore, the high-pressure tank according to the present invention is such that a coloring material that develops color under the influence of an external impact is disposed on the outer periphery of the tank in a state of being mixed with the constituent members constituting the outer peripheral portion of the tank. For example, microcapsules are used as the color former. Further, the constituent member may be a resin material.

  It is also preferable that a colored ink whose hue or brightness changes with time is enclosed in microcapsules encapsulated in a color-developing film.

  In the high-pressure tank according to the present invention, when the high-pressure tank is damaged by an impact, the coloring film, microcapsule, and the like at that portion develop color (refer to, for example, JP-A-10-206342). It is possible to directly grasp and judge the degree of impact from the color development level through vision. In addition, when a plurality of types of color developing films are used, it is possible to determine the details of damage by different colors. Moreover, unlike a conventional device (for example, a detection device using an AE sensor), a device for detecting damage can be configured at a lower cost.

  According to the present invention, damage received by impact can be detected directly and visually at a low cost.

  Hereinafter, the configuration of the present invention will be described in detail based on an example of an embodiment shown in the drawings. In the following embodiments, examples in which the present invention is applied to the fuel tank 21 of the fuel cell system 1 used in a fuel cell vehicle or the like are shown. Hereinafter, the outline of the fuel cell system 1 including the fuel cell 2 and the fuel tank (high-pressure tank) 21 will be described first, and then the configuration of the fuel tank 21 for detecting damage received by impact will be described. .

  As shown in FIG. 1, the fuel cell system 1 includes a fuel cell 2, an oxidizing gas piping system 3, and a fuel gas piping system 4. The fuel cell system 1 can be mounted on a vehicle, but of course can be applied not only to the vehicle but also to various moving bodies (for example, ships, airplanes, robots, etc.) and stationary power sources.

  The fuel cell 2 has a stack structure in which a large number of single cells are stacked. The solid polymer electrolyte type single cell has an air electrode on one surface of the electrolyte membrane, a fuel electrode on the other surface, and a pair of separators so as to sandwich the air electrode and the fuel electrode from both sides. . As the electrolyte membrane, a fluorine-based membrane is generally used. An oxidizing gas is supplied to the oxidizing gas channel 2a of one separator, and a fuel gas is supplied to the fuel gas channel 2b of the other separator. The fuel cell 2 generates electric power by an electrochemical reaction between the supplied oxidizing gas and fuel gas. In addition, the fuel cell 2 generates heat and generates water on the air electrode side due to the electrochemical reaction. The temperature of the solid polymer electrolyte fuel cell 2 is approximately 60 to 80 ° C.

  The oxidizing gas piping system 3 has a supply path 11 and a discharge path 12. The compressor 14 is provided in the supply passage 11, takes in outside air as an oxidizing gas via the air cleaner 13, and pumps it to the oxidizing gas passage 2 a of the fuel cell 2. Moisture exchange is performed between the oxidizing gas fed under pressure and the oxidizing off-gas by the humidifier 15 and humidified appropriately. The oxidizing off gas is discharged from the oxidizing gas flow path 2a to the discharge path 12, and after passing through the air pressure regulating valve 16 and the humidifier 15, is finally exhausted into the atmosphere outside the system as exhaust gas through a muffler (not shown).

  The fuel gas piping system 4 supplies and discharges hydrogen gas as fuel gas to and from the fuel cell 2. The fuel gas piping system 4 includes a hydrogen supply source 21, a supply path 22, a circulation path 23, a hydrogen pump 24, and a purge path 25. The hydrogen gas flows out from the hydrogen supply source 21 to the supply path 22 by opening the main valve 26, and is supplied to the fuel gas flow path 2b through the regulator 27 and the shutoff valve 28. Thereafter, the hydrogen gas is discharged from the fuel gas passage 2b to the circulation passage 23 as hydrogen off gas. The hydrogen off-gas is pumped by a hydrogen pump 24 to a junction A between the circulation path 23 and the supply path 22, merges with the hydrogen gas, and is supplied to the fuel gas flow path 2b again. A part of the hydrogen off-gas is discharged from the circulation path 23 to the purge path 25 by appropriately opening the purge valve 33, and is discharged outside through a hydrogen diluter (not shown).

  Next, the configuration of the fuel tank 21 for detecting damage received by impact will be described (see FIGS. 2 to 10). In the present embodiment, when the fuel tank 21 receives an impact from the outside due to a vehicle collision or the like (see FIG. 2), a coloring material such as a microcapsule is colored so that the impact level can be determined from the coloring level. (See FIG. 3).

<First Embodiment>
A plurality of types of coloring films 41 that develop color under the influence of an external impact are attached to the outer periphery of the fuel tank 21 according to the outer periphery of the tank (see FIGS. 4 and 5). For example, in the case of this embodiment, three types of color films 41 a to 41 c are attached to the outer periphery of the fuel tank 21.

  As the coloring film 41 (41a to 41c), for example, a sheet-like film such as pressure-sensitive paper having a structure in which a coloring layer, an adhesive layer, and the like are laminated and microcapsules are included in the coloring layer can be used. . A microcapsule is a small container enclosing colored ink or the like, and bursts by receiving an external force of a predetermined size to disperse the colored ink or the like. A known film may be used as the above-described coloring film 41 or microcapsule.

  In this case, it is preferable that the coloring film 41 is attached to each outer peripheral portion of the fuel tank 21. For example, in the present embodiment, three types of color forming films 41 a to 41 c made of a split sheet to generate different colors are used as a dome-shaped tip portion, a cylindrical trunk portion, and a dome-shaped base end portion of the fuel tank 21 (FIG. 4, FIG. 4). In FIG. 5, the respective parts are attached to each other (refer to FIGS. 4 and 5). Further, in this case, if the limit strength is different for each outer peripheral portion of the fuel tank 21, the color development level (surface pressure at which color development occurs) of the color development films 41a to 41c (or the microcapsules included therein) is made different. In addition, if pasting is performed according to the limit strength, the degree of damage can be more accurately determined according to the property (strength) of each part. For example, when the dome-shaped tip or base end is superior in strength to the cylindrical body, the color development levels of the color films 41a and 41c employed for the dome-shaped tip and base end are raised. be able to.

  In the fuel tank 21 configured as described above, since the microcapsules of the color developing films 41a to 41c bonded to the impacted part are ruptured and color is generated at the part, the impact is detected from the color developing level. The degree of damage and the degree of damage received by the part can be directly determined visually. In general, if an external impact is applied to the fuel tank (high pressure tank) 21, the strength and fatigue durability of the tank will decrease. Although it may be difficult to determine particularly serious damage that affects the remaining life, in the present embodiment, the above determination result is used to include whether or not the fuel tank 21 is used continuously. The remaining life can be determined with higher accuracy. In addition, it is possible to adopt a configuration in which damage can be accurately determined at a lower cost than a detection device using a conventional AE sensor.

<Second Embodiment>
In the present embodiment, when the filament (fiber) is wound around the outer periphery of the fuel tank 21 (winding), the coloring layer 41 is formed so as to wind the coloring film 41 (see FIG. 6). In this case, it is preferable that the coloring film 41 is disposed in the vicinity of the surface layer of the fuel tank 21 (portion close to the outer surface) so that the impact from the outside is sufficiently transmitted to the microcapsules.

  A specific example is a fuel tank 21 in which an FRP layer is formed. In this case, the coloring film 41 is wound when the glass fiber is wound to form a coloring layer (see FIG. 6). In addition, in FIG. 6 etc., the cross section of the coloring film 41 wound in the glass fiber and provided in the FRP layer is shown by the black line.

  It is also preferable to use a plurality of types of coloring films 41 that develop different colors (see FIG. 7). By disposing a plurality of types of coloring films 41 (in FIG. 7, two kinds of coloring films are denoted by reference numerals 41d and 41e) in layers such as the outer side, the middle, and the inner side, the damage in the fuel tank 21 progresses to which layer. It becomes easy to judge whether you are doing.

<Third Embodiment>
In the present embodiment, the microcapsule (denoted by reference numeral 42 in FIG. 9) that is a coloring material is arranged on the outer peripheral portion of the fuel tank 21 in a state of being mixed with the members constituting the outer peripheral portion of the fuel tank 21. (See FIGS. 8 and 9). It is preferable that the outer peripheral portion of the fuel tank 21 is configured so that the impact from the outside is sufficiently transmitted to the microcapsule 42.

  A specific example of the fuel tank 21 having such a configuration is a high-pressure hydrogen tank in which an FRP layer is formed. In this case, the microcapsules 42 are mixed on the surface layer side of the FRP layer, and the damage detection made of the resin, fibers and the microcapsules 42 is formed on the outer peripheral side (surface layer side) of the normal layer N made of resin and fibers. Layer D is formed (see FIG. 9).

  In this case, the color development is differentiated by using a plurality of types of microcapsules 42 that develop different colors (for example, red on the inside, yellow on the middle, blue on the outside, etc.), and visually indicate the degree of progress of impact and damage. It is also preferable to make it easier to judge (see FIG. 10). By providing a plurality of mixed layers of the microcapsules 42, it is easy to determine to which layer the damage in the fuel tank 21 has progressed.

  The above-described embodiment is an example of a preferred embodiment of the present invention, but is not limited thereto, and various modifications can be made without departing from the scope of the present invention. For example, in each of the above-described embodiments, the case where the coloring material (the microcapsule 42 or the coloring film 41 including the coloring material) is disposed as a part of the fuel tank 21 in the outer layer (outer peripheral portion) is exemplified. It is good also as applying to 21 other structural members, such as a tank protective cover. For example, if the coloring film 41 is attached to a cover for protecting the fuel tank 21 mounted on the vehicle, the cover first receives an impact from the outside, and therefore the fuel tank 21 is moved to the fuel tank 21 based on the damage received by the cover. It is possible to determine the degree of impact.

  Of course, a coloring material such as the coloring film 41 may be arranged and used in the fuel tank 21 when mounted on the vehicle. However, the coloring film 41 may be used at a stage before that, for example, at a stage before production or transportation. Etc. can also be arranged. In such a case, if there is a drop, collision, impact by a tool, etc. during the manufacturing process or transportation, it is possible to leave the impact history in a form that is easy to detect, for example, easy detection by visual inspection, As a result, quality control functions will be strengthened.

  Further, a colorant whose color and its luminance change with time may be adopted. For example, it is possible to specify the time of color development, that is, the time of impact by the difference in luminance of color development. Alternatively, it is possible to estimate the order (time) of impacts in the fuel tank 21 that has received a plurality of impacts by employing microcapsules in which the color of ink deteriorates with time. In general, even with similar damage, the relatively old and old ones should be judged more severely when judging the remaining life of the product. Use of the change over time is suitable for such a determination.

  In the above-described embodiment, the fuel tank 21 mounted on the vehicle is illustrated as an example of the high-pressure tank. However, this is only a preferable example, and in various tanks such as a pressure vessel that encloses compressed gas or high-pressure liquefied gas. Also, the present invention can be applied.

1 is a diagram schematically showing a configuration example of a fuel cell system mounted on a fuel cell vehicle. FIG. It is a figure which shows a mode that the impact from the outside was added to the fuel tank. It is a figure which shows a mode that it was made to color using coloring materials, such as a microcapsule, when the impact was added. It is a figure which shows the multiple types of coloring film stuck on a fuel tank and its outer periphery. It is a figure which shows the fuel tank by which the multiple types of coloring film were bonded together. It is sectional drawing of the fuel tank which arrange | positioned the coloring film around the FRP layer of the outer periphery. FIG. 3 is a cross-sectional view of a fuel tank in which a plurality of types of coloring films are wound around an outer peripheral FRP layer and arranged in layers. It is sectional drawing of the fuel tank which mixed the microcapsule with the FRP component and distribute | arranged to the outer peripheral part. It is an enlarged view of the rectangular broken line part in FIG. FIG. 5 is a cross-sectional view of a fuel tank in which a plurality of mixed layers of microcapsules are provided on an FRP component. It is a reference figure which shows the high-pressure tank of the conventional structure provided with G sensor and AE sensor.

Explanation of symbols

21 ... Fuel tank (high pressure tank), 41 (41a-41e) ... Coloring film, 42 ... Microcapsule

Claims (8)

  A high-pressure tank characterized in that a plurality of kinds of color-developing films that develop color under the influence of an external impact are bonded to the outer periphery of the tank in accordance with the outer periphery of the tank.   The high-pressure tank according to claim 1, wherein the coloring film is bonded according to a limit strength at a portion of the outer periphery of the tank.   A high-pressure tank characterized in that a color-developing film that develops color under the influence of an external impact is wound into a plurality of layers when the filament is wound around the outer periphery of the tank.   The high-pressure tank according to claim 3, wherein a plurality of types of films having different colors at the time of color development are used as the color development film.   A high-pressure tank characterized in that a coloring material that develops color under the influence of an external impact is disposed on the outer periphery of the tank in a state of being mixed with a constituent member constituting the outer peripheral portion of the tank.   The high pressure tank according to claim 5, wherein microcapsules are used as the coloring material.   The high-pressure tank according to claim 5 or 6, wherein the constituent member is a resin material.   The high pressure tank according to any one of claims 1 to 7, wherein a colored ink whose hue or luminance changes with time is enclosed in a microcapsule included in the coloring film.