JP5369650B2 - High pressure gas tank manufacturing apparatus and high pressure gas tank manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique for removing bubbles generated in a thermosetting resin in a high-pressure gas tank manufactured by a filament winding method. <P>SOLUTION: As regards a high-pressure gas tank manufacturing apparatus 200, while a tank container 10 in which a fiber-reinforced resin layer is formed on the outer surface by winding fibers 20 impregnated with the thermosetting resin is rotated, the whole tank container is heated, and the heat curing treatment of the tank container is implemented. With regard to the high-pressure gas tank manufacturing apparatus 200, in the heat curing treatment, the bubbles generated in the surface layer of the tank container 10 are removed by irradiating the surface layer with supersonic waves by a supersonic wave bubble removing part 230. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a high-pressure gas tank for storing gas.

  The high-pressure gas tank may be mounted on a moving body such as a fuel cell vehicle, and the weight reduction is required. As a method for reducing the weight of a high-pressure gas tank, a method for manufacturing a high-pressure gas tank by a filament winding method (FW method) is known. In the method of manufacturing a high-pressure gas tank by the filament winding method, a fiber impregnated with a thermosetting resin such as an epoxy resin is wound around the outer periphery of a relatively lightweight resin tank container, and the thermosetting resin is thermally cured. , Improve the strength of the tank container.

  However, in the filament winding method, air that has entered between fibers gradually moves to the surface of the thermosetting resin layer during the thermosetting process, and bubbles are generated in the thermosetting resin layer. There was a problem. When bubbles are generated in the thermosetting resin layer in the high-pressure gas tank, irregularities due to the bubbles are generated on the outer surface of the high-pressure gas tank. Then, an error occurs in the dimension of the high pressure gas tank, and the assembling property of the high pressure gas tank is deteriorated. Moreover, such irregularities on the outer surface cause a decrease in the design of the high-pressure gas tank. Furthermore, when sticking a display label etc. on the outer surface of a high pressure gas tank, not only the sticking property of a display label will fall, but the visibility of the stuck display label will also fall. Until now, various techniques have been proposed in order to suppress the generation of bubbles in the thermosetting process of the filament winding method (Patent Document 1, etc.).

JP-A-6-254974 JP 2003-53853 A

  However, even with the above technique, the generation of bubbles in the thermosetting resin has not been sufficiently suppressed in the thermosetting process.

  An object of the present invention is to provide a technique for removing bubbles generated in a thermosetting resin in a high-pressure gas tank manufactured by a filament winding method.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

[Application Example 1]
A high-pressure gas tank manufacturing apparatus that heats the entire tank container in which a fiber-reinforced resin layer is formed on the outer surface by winding fibers impregnated with a thermosetting resin, and heat-treats the fiber-reinforced resin layer. A high-pressure gas tank manufacturing apparatus comprising: a tank container thermosetting unit that performs the above and a bubble removing unit that removes bubbles generated on a surface layer of the tank container using air in the thermosetting process.
According to this high-pressure gas tank manufacturing apparatus, air is used to cure the thermosetting resin by using the air bubbles generated in the thermosetting resin of the high-pressure gas tank manufactured by the filament winding method. Can be easily removed before.

[Application Example 2]
The high-pressure gas tank manufacturing apparatus according to Application Example 1, wherein the bubble removing unit includes an ultrasonic irradiation unit that removes the bubbles by irradiating the bubbles with ultrasonic waves.
According to this high pressure gas tank manufacturing apparatus, bubbles generated in the thermosetting resin can be easily removed by ultrasonic waves.

[Application Example 3]
The high pressure gas tank manufacturing apparatus according to Application Example 1 or Application Example 2, wherein the bubble removing unit includes a negative pressure generating unit that generates a negative pressure around the tank container to remove the bubbles. manufacturing device.
According to the high-pressure gas tank manufacturing apparatus, bubbles can be expanded and broken by the negative pressure generated by the negative pressure generator. Therefore, bubbles generated in the thermosetting resin can be easily removed.

[Application Example 4]
A method for manufacturing a high-pressure gas tank, comprising:
(A) preparing a tank container having a fiber reinforced resin layer impregnated with a thermosetting resin formed on the outer surface;
(B) A step of heating and thermally curing the entire fiber reinforced resin layer, and using air to remove bubbles generated on the surface layer of the tank container.
According to this manufacturing method, bubbles generated in the thermosetting resin layer of the high-pressure gas tank manufactured by the filament winding method are easily removed before the thermosetting resin is cured. be able to.

[Application Example 5]
The manufacturing method according to Application Example 4, wherein the step (b) includes a step of removing the bubbles by irradiating the bubbles with ultrasonic waves.

[Application Example 6]
6. The manufacturing method according to application example 4 or application example 5, wherein the step (b) includes a step of generating a negative pressure around the tank container to remove the bubbles.

  The present invention can be realized in various forms. For example, a high-pressure gas tank manufacturing apparatus, a high-pressure gas tank manufacturing method, a computer program for realizing the functions of these methods or apparatuses, and the computer program therefor Can be realized in the form of a recording medium or the like on which is recorded. In addition, the present invention can be realized in the form of, for example, a high-pressure gas tank, a vehicle including the high-pressure gas tank, and the like.

A. First embodiment:
FIGS. 1A to 1C are schematic views for explaining a part of a manufacturing process of a high-pressure gas tank by a filament winding method as one embodiment of the present invention. FIG. 1A is a schematic diagram showing a tank container 10. In manufacturing the high-pressure gas tank, first, the tank container 10 is prepared as a first step. The tank container 10 is a hollow container having a substantially cylindrical cylinder portion 11 and substantially dome-shaped dome portions 13 provided at both ends thereof. The tank container 10 is made of, for example, a resin such as nylon resin. In addition, the tank container 10 may have another shape and may be configured by other members.

  FIG. 1B is a schematic diagram showing a process of winding the carbon fiber 20 around the outer surface of the tank container 10. In this step, the tank container 10 is attached to the rotation drive unit 110 and rotated about the central axis CX of the cylinder unit 11. Further, the carbon fiber 20 is wound around the outer surfaces of the cylinder portion 11 and the dome portion 13 while the reel 120 around which the carbon fiber 20 is wound is reciprocated along the axial direction of the central axis CX. The carbon fiber 20 is pre-impregnated with an epoxy resin that is a thermosetting resin. This thermosetting resin functions as an adhesive for the carbon fiber 20 by being thermoset by a thermosetting process described later.

  FIG. 1C is a schematic diagram showing the tank container 10 after the carbon fiber 20 is wound thereon. The strength of the tank container 10 is improved by winding the carbon fiber 20 around the outer surface. Hereinafter, the tank container 10 around which the carbon fiber 20 is wound is referred to as a “fiber reinforced tank container 10”. In the fiber reinforced tank container 10, for example, a fiber reinforced layer of carbon fibers 20 is formed with a thickness of about 20 μm to 30 μm with respect to a thickness of a nylon resin container wall of about 3 mm.

  FIG. 2A is a schematic perspective view illustrating a thermosetting processing apparatus 200 that performs a thermosetting process for thermosetting the thermosetting resin of the fiber reinforced tank container 10. In FIG. 2A, a partition 215 that covers the entire apparatus is shown by a broken line. In FIG. 2A, arrows x, y and z indicating three-dimensional directions orthogonal to each other are shown. The arrow z direction coincides with the upward direction of gravity, and the arrow y direction coincides with the axial direction of the central axis CX of the fiber reinforced tank container 10.

  FIG. 2B is a schematic side view of the thermosetting apparatus 200 as viewed from the direction along the x-axis direction of FIG. Note that in FIG. 2B, illustration of the partition wall 215 illustrated by a broken line in FIG. 2A is omitted. FIG. 2B also shows arrows x, y, and z corresponding to the arrows x, y, and z in FIG.

  The thermosetting apparatus 200 includes a base 210, tank mounting parts 221 and 222, a rotation driving part 225, and an ultrasonic bubble removing part 230 in an internal space WS surrounded by a partition wall 215. The tank mounting parts 221 and 222 and the rotation driving part 225 are respectively arranged on the base 210. The tank attachment portions 221 and 222 hold the fiber reinforced tank container 10 from both ends so that the fiber reinforced tank container 10 can be rotated about its central axis CX. The rotation drive unit 225 can rotate the fiber reinforced tank container 10 held by the tank mounting units 221 and 222 in the direction of arrow R at a substantially constant speed.

  As the thermosetting process, the thermosetting apparatus 200 raises the temperature in the space WS to about 130 ° C. while rotating the fiber reinforced tank container 10 attached to the tank attaching parts 221 and 222 by the rotation driving part 225. The fiber reinforced tank container 10 is heated for about 7 to 8 hours. Thereby, the thermosetting resin impregnated in the carbon fiber 20 is thermoset. In general, when the thermosetting resin is heated for thermosetting, the viscosity of the thermosetting resin is once lowered and softened until it becomes almost liquid. In addition, when the thermosetting resin is further heated from the softened state, the crosslinking reaction proceeds and is cured.

  Further, the thermosetting resin has a property of shrinking with curing. Therefore, as the curing of the thermosetting resin proceeds, a force acts on the fiber reinforced tank container 10 in a direction in which the tank diameter decreases due to the shrinkage of the thermosetting resin. Therefore, in this thermosetting processing apparatus 200, the pressure inside the fiber reinforced tank container 10 is adjusted by a tank internal pressure adjusting unit (not shown), and the tank diameter is reduced by contracting the pressure and the thermosetting resin. The force acting on the balance is balanced, and the tank diameter is prevented from being reduced in the thermosetting process.

  By the way, in the fiber reinforced layer of the fiber reinforced tank container 10, there are air that has entered between the fibers when the carbon fiber 20 is wound, air that has originally entered the carbon fiber 20, and the like. As described above, in the thermosetting process of the fiber reinforced tank container 10, when the viscosity of the thermosetting resin is relatively lowered, the air entering the fiber reinforced layer moves through the thermosetting resin. It becomes easy to do. Accordingly, in the thermosetting treatment step, bubbles may be generated on the outer surface of the fiber reinforced layer by such air moving in the thermosetting resin toward the surface layer of the fiber reinforced layer.

  If the thermosetting resin is cured while bubbles are generated on the outer surface of the fiber reinforced layer, irregularities due to the bubbles are generated on the outer surface of the fiber reinforced tank container 10. If the fiber reinforced tank container 10 has such irregularities, it may cause a dimensional error of the high-pressure gas tank as a finished product, and the assembling property of the high-pressure gas tank may be deteriorated. In addition, such irregularities on the outer surface may cause a decrease in the design of the high-pressure gas tank. This also causes a reduction in the visibility of the displayed label.

  Therefore, the thermosetting apparatus 200 of the present embodiment is provided with an ultrasonic bubble removing unit 230 for physically removing bubbles generated on the outer surface of the fiber reinforced tank container 10 in the thermosetting process. . The ultrasonic bubble removing unit 230 includes a hollow resonance chamber 231, a nozzle 233, and an ultrasonic emission unit 235. The nozzle 233 has an injection port inserted into the resonance chamber 231 from the upper side in the direction of gravity, and can inject high-pressure air (compressed air) into the resonance chamber 231. The air in the resonance chamber 231 is vibrated by the injection of high-pressure air from the nozzle 233, and ultrasonic waves are emitted from the ultrasonic emission unit 235 provided on the lower side of the resonance chamber 231 in the gravity direction. Note that the frequency of the ultrasonic wave can be changed by adjusting the distance between the nozzle 233 and the bottom of the resonance chamber 231.

  The ultrasonic bubble removing unit 230 is attached to the upper side in the gravity direction of the fiber reinforced tank container 10 attached to the tank attaching units 221 and 222 so as to be movable in the direction along the arrow y. Moreover, the ultrasonic bubble removal part 230 can also move to the direction along the arrow z, and can adjust the distance between the fiber reinforced tank containers 10. With this configuration, the ultrasonic bubble removing unit 230 breaks and removes bubbles by irradiating ultrasonic waves on the outer surface of the fiber reinforced tank container 10 that is rotationally driven in the thermosetting process.

  FIG. 3 is a schematic diagram for explaining bubble removal by the ultrasonic bubble removing unit 230 in the thermosetting process. FIG. 3 is an enlarged schematic cross-sectional view of the broken line region 3 shown in FIG. FIG. 3 shows a partial cross section of the container wall of the fiber reinforced tank container 10, a partial cross section of the fiber reinforced layer 20 </ b> L laminated on the container wall and formed of the carbon fiber 20 and the thermosetting resin 23, An arrow indicating the traveling direction of the sound wave is schematically shown. The thermosetting resin 23 is in a relatively softened state before being cured.

  As described in FIG. 2, bubbles 25 are generated in the softened thermosetting resin 23, and the bubbles 25 gradually move toward the surface layer of the fiber reinforced layer 20L. Therefore, in the thermosetting apparatus 200 of the present embodiment, the ultrasonic bubble removing unit 230 irradiates the fiber reinforcing layer 20L facing the ultrasonic emitting unit 235 with ultrasonic waves to break the bubbles 25. As described above, the ultrasonic bubble removing unit 230 can remove the bubbles 25 without directly contacting the thermosetting resin 23. Therefore, it is possible to avoid damaging the outer surface of the fiber reinforced tank container 10 by contacting the thermosetting resin 23 in the bubble removing step.

  The inventors of the present invention have experimentally confirmed that it is preferable to irradiate ultrasonic waves of 150 dB or more in order to break the bubbles 25. In addition, the ultrasonic wave is removed by the ultrasonic bubble removing unit 230 is preferably in the initial time period of the thermosetting process in which the viscosity of the thermosetting resin is relatively low in the thermosetting process. This is because the lower the viscosity of the thermosetting resin, the easier it is to break the bubbles.

  After the thermosetting process is completed, the fiber reinforced tank container 10 is removed from the thermosetting apparatus 200, and a high-pressure gas tank is manufactured using the fiber reinforced tank container 10. Thus, according to the configuration of the present embodiment, in the thermosetting treatment of the high-pressure gas tank manufactured by the filament winding method, the thermosetting resin layer is avoided while avoiding direct contact with the thermosetting resin. Bubbles generated in can be removed by ultrasonic waves.

B. Second embodiment:
FIGS. 4A and 4B are schematic views showing the configuration of a thermosetting apparatus 200A as a second embodiment of the present invention. 4 (A) and 4 (B) are substantially the same as FIGS. 2 (A) and 2 (B), respectively, except that a negative pressure type bubble removing unit 240 is provided instead of the ultrasonic bubble removing unit 230. is there. The fiber reinforced tank container 10 is prepared in the same manner as in the first embodiment (FIG. 1) and attached to the thermosetting apparatus 200A.

  The negative pressure type bubble removing unit 240 includes a nozzle 241 and a deflector 243 attached to the tip of the nozzle 241. The nozzle 241 injects high-pressure air in the direction of gravity. The deflector 243 can block the high-pressure air ejected from the nozzle 241 and change the flow from the gravity direction to the lateral direction intersecting the gravity direction. The negative pressure type bubble removing unit 240 is attached to the upper side in the gravity direction of the fiber reinforced tank container 10 so as to be movable in the direction along the arrow y. Further, the negative pressure type bubble removing unit 240 can move in the direction along the arrow z, and the distance between the deflector 243 and the fiber reinforced tank container 10 can be adjusted.

  FIG. 5 is a schematic diagram for explaining the removal of bubbles by the negative pressure type bubble removing unit 240. FIG. 5 is substantially the same as FIG. 3 except that a part of the negative pressure type bubble removing unit 240 is added and that an arrow indicating an air flow is shown instead of an arrow indicating an ultrasonic wave. It is. The negative pressure type bubble removing unit 240 injects high-pressure air from the nozzle 241 toward the fiber reinforced tank container 10 during the thermosetting process. The high-pressure air ejected from the nozzle 241 becomes an air jet flow in the lateral direction by the deflector 243 and generates a negative pressure below the deflector 243. Due to the negative pressure generated between the fiber reinforced layer 20L and the deflector 243, the bubbles 25 in the thermosetting resin 23 are expanded and broken.

  As described above, according to the negative pressure type bubble removing unit 240, the partial area of the outer surface of the fiber reinforced tank container 10 facing the deflector 243 is set to a negative pressure from the other areas, thereby reducing the partial area. The bubbles 25 generated in the thermosetting resin 23 can be broken. The negative pressure type bubble removing unit 240 is subjected to a reciprocating motion in the direction along the rotation axis CX of the fiber reinforced tank container 10 and a rotational motion by the rotation driving unit 225 of the fiber reinforced tank container 10 during the thermosetting process. The air bubbles on the entire outer surface of the fiber reinforced tank container 10 can be removed.

  By the way, if the bubble removing process is executed by the negative pressure type bubble removing unit 240 before the thermosetting resin 23 starts to be cured, the generated negative pressure causes the air present inside the fiber reinforced layer 20L to be exposed to the outside. Can be directed towards. That is, the generation of the bubbles 25 can be promoted and the bubbles 25 can be removed in the time zone in which the bubbles 25 are relatively easy to break and the thermosetting resin 23 is relatively soft. Therefore, the bubbles 25 can be removed more effectively.

  As described above, according to the thermosetting apparatus 200A of the second embodiment, in the thermosetting process, a negative pressure region is generated on the outer periphery of the fiber reinforced tank container 10 to remove bubbles. Therefore, in the thermosetting treatment of the high-pressure gas tank manufactured by the filament winding method, it is possible to easily remove bubbles generated in the thermosetting resin layer while avoiding direct contact with the thermosetting resin. Can do.

C. Variations:
The present invention is not limited to the above-described examples and embodiments, and can be implemented in various modes without departing from the gist thereof. For example, the following modifications are possible.

C1. Modification 1:
In the said Example, the ultrasonic bubble removal part 230 and the negative pressure type bubble removal part 240 removed the bubble produced in the surface layer of the fiber reinforced tank container 10 by utilizing air. However, the bubble removing unit may remove the bubbles by other means using air. For example, the bubbles 25 may be broken by injecting high-pressure air toward the bubbles 25. Thus, it is good also as what removes a bubble by applying external force to a bubble using air as a medium.

C2. Modification 2:
In the above embodiment, the carbon fiber 20 is impregnated with an epoxy resin as a thermosetting resin. However, the carbon fiber 20 may be impregnated with another thermosetting resin. For example, as the thermosetting resin, phenol resin, urea resin, melamine resin, unsaturated polyester resin, or the like may be used.

  Moreover, in the said Example, although the thermosetting resin was previously impregnated to the carbon fiber 20, the thermosetting resin does not need to be impregnated beforehand. For example, the thermosetting resin may be impregnated in the carbon fiber 20 in the step of winding the carbon fiber 20 around the tank container 10.

C3. Modification 3:
In the first embodiment, the ultrasonic bubble removing unit 230 of the thermosetting apparatus 200 generates ultrasonic waves by jetting compressed air from the nozzle 233. However, the ultrasonic bubble removing unit 230 may generate ultrasonic waves by other methods. For example, ultrasonic waves may be generated by a magnetostrictive element using ferrite or a vibrator using a piezoelectric element.

C4. Modification 4:
In the said 2nd Example, the negative pressure type bubble removal part 240 was generating the negative pressure on the outer periphery of the fiber reinforced tank container 10 with the flow of the air jet. However, the negative pressure type bubble removing unit 240 may generate negative pressure by other methods. For example, a negative pressure may be generated in a partial region of the outer surface of the fiber reinforced tank container 10 by a vacuum device that sucks air.

The schematic diagram for demonstrating the preparation process of a fiber reinforced tank container. Schematic which shows the structure of the thermosetting processing apparatus of 1st Example. The schematic diagram for demonstrating the bubble removal process of the fiber reinforcement layer surface layer in 1st Example. Schematic which shows the structure of the thermosetting processing apparatus of 2nd Example. The schematic diagram for demonstrating the bubble removal process of the fiber reinforcement layer surface layer in 2nd Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Tank container, fiber reinforced tank container 11 ... Cylinder part 13 ... Dome part 20 ... Fiber 20L ... Fiber reinforced layer 23 ... Thermosetting resin 25 ... Bubble 110 ... Rotation drive part 120 ... Reel 200, 200A ... Thermosetting processing apparatus 210: Base 215 ... Bulkheads 221, 222 ... Tank mounting part 225 ... Rotation drive part 230 ... Ultrasonic bubble removal part 231 ... Resonance chamber 233 ... Nozzle 235 ... Ultrasonic injection part 240 ... Negative pressure type bubble removal part 241 ... Nozzle 243 ... Deflector CX ... Center axis R ... Arrow WS ... Internal space

Claims (6)

A high-pressure gas tank manufacturing device,
A tank container thermosetting unit that heats the entire tank container in which a fiber reinforced resin layer is formed on the outer surface by wrapping fibers impregnated with a thermosetting resin, and executes a thermosetting process of the fiber reinforced resin layer When,
In the thermosetting treatment, an air bubble removing unit that removes air bubbles generated on the surface layer of the tank container by an ultrasonic wave using air as a medium or a negative pressure generated by air injection ;
A high-pressure gas tank manufacturing apparatus comprising: The high-pressure gas tank manufacturing apparatus according to claim 1,
The said bubble removal part is a high pressure gas tank manufacturing apparatus provided with the ultrasonic irradiation part which removes the said bubble by irradiating an ultrasonic wave to the said bubble. The high-pressure gas tank manufacturing apparatus according to claim 1 or 2,
The said bubble removal part is a high pressure gas tank manufacturing apparatus provided with the negative pressure generation part which generates the negative pressure around the said tank container and removes the said bubble. A method for manufacturing a high-pressure gas tank, comprising:
(A) preparing a tank container having a fiber reinforced resin layer impregnated with a thermosetting resin formed on the outer surface;
(B) The entire fiber reinforced resin layer is heated and thermally cured, and bubbles generated in the surface layer of the tank container are generated by ultrasonic waves using air as a medium or negative pressure generated by air injection. Removing, and
A manufacturing method comprising: The manufacturing method according to claim 4,
The said process (b) is a manufacturing method including the process of removing the said bubble by irradiating the said bubble with an ultrasonic wave. The manufacturing method according to claim 4 or 5, wherein
The step (b) includes a step of generating a negative pressure around the tank container to remove the bubbles.

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