JP2011046202A - Repairing method for honeycomb sandwich panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reinforcing method for a honeycomb sandwich panel, which reinforces a desired region to be reinforced of the honeycomb sandwich panel while suppressing a decrease in the quality of a product or an increase in air force resistance, and a repairing method for the pinhole formed on the outer sheet of the honeycomb sandwich panel. <P>SOLUTION: In the reinforcing method for the honeycomb sandwich panel, the holes 21 communicating with cells 11 are bored on the outer sheet 20 and the peripheral regions of the holes 21 are covered with a cover material 30 to hermetically close the holes 21 while the pressure in the cells 11 is set to high vacuum pressure by drawing a vacuum to provide a resin sump 40 outside the cover material 30 to store a liquid resin 50 and the resin 50 is allowed to flow in the cells 11 through the holes 21 under the high vacuum pressure in the cells 11 to be cured. In the repairing method for the honeycomb sandwich panel, the liquid resin 50 is stored in the resin sump 40 provided outside the pinhole 22, a pressure difference is produced between the inside and outside of the cells 11 adjacent to the pinhole 22 by heating and cooling and the resin 50 in the resin sump 40 is charged in the pinhole 22 through a resin inflow hole 41 under the pressure difference to be cured. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for reinforcing and repairing a honeycomb sandwich panel.

  Currently, honeycomb sandwich panels that are lightweight and exhibit excellent strength against bending stress, shear stress, and the like are used as structural members for aircraft and the like. The honeycomb sandwich panel is configured by adhering an outer plate of a fiber reinforced resin composite material on both surfaces of a honeycomb core made of a metal material or a synthetic resin.

  There has been proposed a technique for reinforcing a specific portion of the honeycomb sandwich panel (a portion requiring high compressive strength or a portion to which a metal fitting such as a fastener is attached). For example, when manufacturing the honeycomb sandwich panel 100 as shown in FIG. 7A, specific cells (cells to be reinforced) 111 of the honeycomb core 110 are prefilled with a filler 200 such as a resin or a potting agent. After that, a reinforcing method has been proposed in which the outer plate 120 is bonded to the honeycomb core 110 by heating (or the outer plate 120 is formed by bringing the prepreg into close contact with the honeycomb core 110 and heat-curing it).

  On the other hand, a technique for repairing the pinhole 121 formed in the outer plate 120 of the honeycomb sandwich panel 100 shown in FIG. For example, as shown in FIG. 8B, the pinhole 121 of the outer plate 120 is filled with a filler 300 such as a resin, and the patch 400 is attached to the surface of the outer plate 120 with an adhesive 410 to pinhole 121. Has been proposed (see, for example, Patent Document 1).

JP-A-10-156633

  However, when the conventional reinforcing method is adopted, the following problems occur. First, air is mixed when the filler 200 is filled into the cells 111 of the honeycomb core 110, and as shown in FIG. 7 (a), voids 112 are formed in the filled portions in the cells 111, and a desired compressive strength is formed. There is a problem that cannot be obtained. In addition, the filler 200 filled in the cells 111 of the honeycomb core 110 is thermally expanded by heating at the time of adhesion or curing molding of the outer plate 120, and as shown in FIG. 122 is formed, the quality is deteriorated, and there is a problem that aerodynamic resistance is increased in a portion where the air flow is touched. Further, due to the heat shrinkage strain due to cooling of the outer plate 120 after heating, a tensile stress acts on the filler 200, and as shown in FIG. The problem that the intensity | strength and quality of this will fall occurred.

  Further, when the conventional repair method as described in Patent Document 1 is adopted, the patch 400 is attached to the surface of the outer plate 120 of the honeycomb sandwich panel 100, so that the aerodynamic resistance is increased and the weight of the product is increased. It will increase. Further, since the pinhole 121 of the honeycomb sandwich panel 100 is usually generated on the outer surface side of the machine body, if the patch 400 is used for repairing the pinhole 121, the appearance of the product is impaired and the quality is deteriorated. It becomes.

  An object of the present invention is to provide a method for reinforcing a honeycomb sandwich panel that can reinforce a desired reinforcing portion without causing a decrease in strength and quality of a product and an increase in aerodynamic resistance.

  Another object of the present invention is to provide a method for repairing a honeycomb sandwich panel capable of repairing a pinhole formed in an outer plate without causing a decrease in product quality or an increase in weight / aerodynamic resistance. It is.

  In order to solve the above problems, a first method for reinforcing a honeycomb sandwich panel includes a honeycomb core and a reinforcing panel of a fiber reinforced resin composite material bonded to both surfaces of the honeycomb core. A hole drilling step of drilling a hole leading to a cell to be reinforced of the honeycomb core in one of the outer plates, and covering the peripheral region of the hole with a covering material; Covering and sealing step for making a specific space surrounded by the covering material airtight, and exhausting air from the specific space and the cell to set the pressure in the specific space and the cell to a predetermined vacuum pressure A vacuuming step, a resin reservoir step in which a resin reservoir is provided outside the covering material, and a liquid resin is stored in the resin reservoir, and the resin in the resin reservoir is passed through the holes by the vacuum pressure in the cell. Characterized in that it comprises a resin feeding step of flowing into the cell, and a resin curing step of curing the resin which has flowed into the cell Te.

  According to a second aspect of the present invention, in the reinforcing method of the first honeycomb sandwich panel, in the resin reservoir step, the resin in the resin reservoir is adjacent to the hole with the coating material interposed therebetween, and in the resin inflow step, the coating is performed. A resin inflow hole is formed in a portion adjacent to the hole of the material, and the pressure difference between the atmospheric pressure acting on the resin in the resin reservoir and the vacuum pressure in the specific space and the cell, The resin in the resin reservoir is caused to flow into the cell through the resin inflow hole and the hole.

According to a third method for reinforcing a honeycomb sandwich panel, in a honeycomb sandwich panel in which a fiber reinforced resin composite outer plate is bonded on both sides, a hole leading to a cell is provided on one outer plate, and the honeycomb sandwich panel is formed with the hole on the upper side. A step of placing a panel; a step of forming a sealed space having a predetermined volume between the outer plate and the outer plate so as to cover the hole; and a hole communicating with the sealed space to connect to an air discharge means and the sealing A step of providing another hole communicating with the space to connect to a resin reservoir containing resin, a step of discharging air from the sealed space by the air discharging means, and a step of sending resin from the resin reservoir and storing the resin in the sealed space And introducing air into the sealed space and pressurizing the resin in the sealed space to flow into the cell;
And a step of curing the introduced resin.

The method for repairing a honeycomb sandwich panel according to claim 1 is formed on the outer plate of the honeycomb sandwich panel having a honeycomb core and a fiber reinforced resin composite outer plate bonded to both surfaces of the honeycomb core. A method of repairing a pinhole, wherein a resin reservoir is provided outside the honeycomb sandwich panel so as to surround the pinhole with the pinhole facing upward, and a liquid resin is stored in the resin reservoir, A step of covering the pinhole; a step of heating the surrounding area of the pinhole to expand air in the cells of the honeycomb core adjacent to the pinhole, and discharging a part of the air; In the cell of the honeycomb core adjacent to the pinhole, by cooling the peripheral area of the pinhole following the heating step A cooling step to produce a pressure difference,
A resin filling step of filling the pinhole with the resin in the resin reservoir through a resin inflow hole due to a pressure difference between the inside and outside of the cell generated by the cooling step;
And a resin curing step of curing the resin filled in the pinhole.

The method for repairing a honeycomb sandwich panel according to claim 2 is formed on the outer plate of the honeycomb sandwich panel having a honeycomb core and a fiber reinforced resin composite outer plate bonded to both surfaces of the honeycomb core. A method of repairing a pinhole, the heating step of heating a peripheral region of the pinhole to expand air in the cells of the honeycomb core adjacent to the pinhole and discharging a part thereof,
A sealed space forming step of forming a sealed space by covering the pinhole from the outside of the outer plate to form a sealed space, a resin reservoir step of providing a resin reservoir in which liquid resin is stored outside the sealed space, and the heating step. A cooling step for cooling the surrounding area of the heated pinhole to depressurize the inside of the cell, and a hole that leads from the resin reservoir to the pinhole are provided, and the resin generated by the pressure difference between the cell generated in the cooling step and the atmosphere A resin filling step for filling the pinhole with the resin in the reservoir, and a resin curing step for curing the resin filled in the pinhole.

  According to any one of the first to third aspects of the invention, since the resin is filled in the vacuum cell, the entire cell can be reliably filled with resin, and the formation of voids in the cell can be prevented. . As a result, it is possible to prevent a reduction in strength and quality of the product after reinforcement. Further, since the reinforcement can be performed after the outer plate is bonded to the honeycomb core and the honeycomb sandwich panel is manufactured, the smoothness of the outer plate and the cracking of the filler do not occur. As a result, it is possible to prevent a decrease in strength and quality of the product and an increase in aerodynamic resistance.

  In addition, since it is possible to reinforce after manufacturing the honeycomb sandwich panel by bonding the outer plate to the honeycomb core, the conventional reinforcing method (method of bonding the outer plate after filling the cell with the filler) was adopted. In this case, the problem of poor smoothness of the outer plate and the problem of cracking of the filler can be solved all at once. As a result, it is possible to prevent a decrease in strength and quality of the product and an increase in aerodynamic resistance.

  According to the first or second aspect of the invention, the pinhole can be closed without using the “patch”. As a result, it is possible to prevent the quality of the product from deteriorating and to prevent the product from increasing in weight and aerodynamic resistance.

It is a perspective view which shows the jig | tool used for the reinforcement method which concerns on the 1st Embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is for demonstrating the reinforcement method which concerns on the 1st Embodiment of this invention, (a) is explanatory drawing which shows the state before pouring resin into the cell of a honeycomb core, (b) is a resin dam. FIG. 6 is an explanatory view showing a state where the resin inflow hole is formed in the cell and the resin is made to flow into the cell, and (c) is an explanatory view showing a state where the filling of the resin into the cell is completed. It is a perspective view which shows the jig | tool used for the reinforcement method which concerns on the 2nd Embodiment of this invention. It is for demonstrating the reinforcement method which concerns on the 2nd Embodiment of this invention, (a) is explanatory drawing which shows the state before pouring resin into a vacuum vessel, (b) is a cell of a honeycomb core Explanatory drawing which shows the state before making resin flow in, (c) is explanatory drawing which shows the state which is flowing resin into a cell. BRIEF DESCRIPTION OF THE DRAWINGS It is for demonstrating an example of the repair method which concerns on embodiment of this invention, (a) is explanatory drawing which shows the state which has heated the surrounding area of the pinhole arrange | positioned upward, (b) is resin It is explanatory drawing which shows the state which has filled the resin in a reservoir into the pinhole. It is for demonstrating the other example of the repair method which concerns on embodiment of this invention, (a) is explanatory drawing which shows the state which has heated the surrounding area of the pinhole arrange | positioned below, (b) FIG. 5 is an explanatory view showing a state where a resin in a resin reservoir is filled in a pinhole. 1 shows a cross section of a honeycomb sandwich panel reinforced by a conventional reinforcing method, (a) is a cross sectional view showing a state in which a void is formed inside a filler filled in a cell, and (b) is a cell. It is sectional drawing which shows the state by which the crack was generate | occur | produced in the filler with which it filled and the convex part was formed in the outer plate | board. It is for demonstrating the conventional repair method, (a) is explanatory drawing which shows the pinhole formed in the outer panel of a honeycomb sandwich panel, (b) is filling the resin into the pinhole shown to (a) It is explanatory drawing which shows the state which affixed and the patch which covers a pinhole while doing.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

<Reinforcing method for honeycomb sandwich panel>
Initially, the reinforcement method of the honeycomb sandwich panel which concerns on embodiment of this invention is demonstrated using FIGS. 1-4. In the present embodiment, resin is filled into a predetermined reinforcing portion of a honeycomb sandwich panel 1 having a honeycomb core 10 and an outer plate 20 of a fiber reinforced resin composite material bonded to both surfaces of the honeycomb core 10. A method of reinforcing will be described.

[First embodiment]
First, a reinforcing method according to the first embodiment of the present invention will be described with reference to FIGS. 1 and 2. As shown in FIG. 2 (a), a hole 21 leading to a specific cell (cell to be reinforced) 11 of the honeycomb core 10 is drilled in one outer plate 20 of the honeycomb sandwich panel 1 (hole drilling step). ). In the present embodiment, as shown in FIG. 2A, four holes 21 communicating with the four cells 11 are formed. The diameter of the hole 21 is set to a value (for example, about 1 mm) that does not deteriorate the strength and quality of the honeycomb sandwich panel 1 while allowing inflow of resin.

  Next, as shown in FIGS. 1 and 2, the peripheral region of the hole 21 formed in the outer plate 20 of the honeycomb sandwich panel 1 is covered with a bagging film 30 as a covering material, and a sealant 31 is provided around the covered portion. By arranging the above, the specific space surrounded by the outer plate 20 and the bagging film 30 is made airtight (covering sealing step). The shape and area of the region covered with the bagging film 30 (the region surrounding the hole 21) can be appropriately determined according to the shape of the outer plate 20, the position, size, number, and the like of the holes 21. In the covering and sealing step in the present embodiment, as shown in FIG. 2A, a deaeration breather 32 is disposed between a region around the hole 21 formed in the outer plate 20 and the bagging film 30. At the same time, a vacuum cap 33 is provided on the bagging film 30.

  Next, as shown in FIGS. 1 and 2, a vacuum pump (not shown) is connected to the vacuum cap 33 via a vacuum tube 34, and air is discharged from the specific space and the cell 11 using this vacuum pump. (Evacuation) is performed, and the pressure in the specific space and the cell 11 is set to a predetermined vacuum pressure (evacuation step). The resin filling rate in the cell 11 is determined by the degree of vacuum and the sealing property in the cell 11. In the vacuuming step in the present embodiment, the specific space and the cell 11 are set to a high vacuum pressure (for example, 760 Torr).

  Next, as shown in FIGS. 1 and 2, a resin dam 40 as a resin reservoir is formed outside the bagging film 30 using a sealant, and a liquid resin 50 is injected and stored inside the resin dam 40. Thus, the resin 50 is made to be adjacent to the hole 21 with the bagging film 30 therebetween (resin storing step). As the resin 50 used in the resin reservoir process, a resin that can obtain relatively high fluidity (low viscosity) under low temperature conditions (for example, 100 ° C. or less) and is cured under low temperature conditions is adopted. For example, “High sole EA-9396 (trade name: manufactured by HENKEL LOCTITE AEROSPACE)” or the like can be employed.

  In the resin reservoir step, a heating lamp (not shown) is disposed in the vicinity of the resin dam 40, and a thermocouple thermometer 45 is connected to the resin dam 40 as shown in FIG. The fluidity (viscosity) of the resin 50 is maintained by heating to about 50 ° C. and maintaining the temperature. The resin reservoir used in the resin reservoir process is not limited to the resin dam 40 made of a sealant. For example, a metal or synthetic resin container may be employed. However, when a metal or synthetic resin container is used as the resin reservoir, a resin inflow hole is provided in advance at the bottom, and the resin inflow hole is closed with a seal film or the like. The periphery of the resin dam 40 is sealed with a sealant.

  Next, as shown in FIG. 2 (b), the resin inflow holes 41 and 35 are formed by piercing the needle 60 into the bottom of the resin dam 40 and the specific part of the bagging film 30 (the part adjacent to the hole 21). The liquid resin 50 stored in the resin dam 40 is passed through the resin inflow holes 41 and 35 and the hole 21 due to the pressure difference between the atmospheric pressure acting on the resin 50 and the vacuum pressure in the specific space and the cell 11. To flow into the cell 11 (resin inflow step). In the resin inflow process, the resin 50 is appropriately supplemented inside the resin dam 40 so that the resin 50 inside the resin dam 40 does not completely flow out.

  After the resin inflow step is completed, the vacuum tube 34 is removed from the vacuum cap 33 to prevent leakage, and then the resin 50 that has flowed into the cell 11 is left with the bagging film 30 and the resin dam 40 left in place. Curing (resin curing process). In the resin curing step, the resin 50 remaining inside the resin dam 40 is also cured as it is. After confirming the completion of the curing of the resin 50, the resin dam 40 and the needle 60 are removed from the bagging film 30, and the bagging film 30 and the like are peeled off from the outer plate 20 to remove excess resin attached to the surface of the outer plate 20. .

Thereafter, the remaining cells 11 are filled with the resin 50 in the cells 11 by sequentially performing the vacuuming step, the resin reservoir step, the resin inflow step, and the resin curing step. Then, as shown in FIG. 2C, it is confirmed that all the cells 11 to be reinforced are filled with the resin 50 and reinforced, and the operation is finished.
The holes 21 of the cells not filled with resin other than the cells adjacent to the resin dam 40 and filled with the resin may be closed with an adhesive film. This is to prevent the resin from being fully filled and cured.

  In the reinforcing method according to the embodiment described above, a hole 21 communicating with the cell 11 to be reinforced of the honeycomb core 10 of the honeycomb sandwich panel 1 is formed in one outer plate 20, and a region around the hole 21 is defined. A specific space covered with the bagging film 30 and surrounded by the outer plate 20 and the bagging film 30 is made airtight. After the air is discharged from the specific space and the cell 11 to set the pressure in the specific space and the cell 11 to a high vacuum pressure, the bottom of the resin dam 40 provided on the hole 21 with the bagging film interposed therebetween. And by making the resin inflow holes 41 and 35 in a specific part (the part adjacent to the hole 21) of the bagging film 30, the resin 50 in the resin dam 40 flows into the cell 11 and is cured.

  Accordingly, since the liquid resin 50 is allowed to flow into the cell 11 in a high vacuum state and cured, the resin 50 can be reliably filled in the entire cell 11 and the formation of voids in the cell 11 can be prevented. can do. As a result, it is possible to prevent a reduction in strength and quality of the product after reinforcement.

  Further, in the reinforcing method according to the embodiment described above, the reinforcing can be performed after the outer plate 20 is bonded to the honeycomb core 10 and the honeycomb sandwich panel 1 is manufactured. Therefore, the conventional method described with reference to FIG. To solve the problem of smoothness of the outer plate and cracking of the filler that occurred when the reinforcing method (adhesion of the outer plate after filling the cell with the filler) was adopted at once. Can do. As a result, it is possible to prevent a decrease in strength and quality of the product and an increase in aerodynamic resistance.

  In the reinforcing method according to the embodiment described above, the filling of the resin 50 is performed for each cell 11 by sequentially performing the evacuation process, the resin reservoir process, the resin inflow process, and the resin curing process for each cell 11. Although the example which performed was shown, the resin inflow path which connects the holes 21 using glass fiber fabric etc. was provided, and resin 50 was poured into all the cells 11 by this resin inflow path at one time. And can be cured. When such a method is employed, it is only necessary to perform the vacuuming step, the resin reservoir step, the resin inflow step, and the resin curing step once, so that the working time and labor can be greatly reduced. In this case, it is necessary to sufficiently consider the characteristics of the resin, the securing of the resin flow path, and the time for filling the resin in all the cells.

[Second Embodiment]
Next, a reinforcing method according to the second embodiment of the present invention will be described with reference to FIGS. In the reinforcing method according to the present embodiment, instead of the bagging film 30, the resin dam 40, and the vacuum pump in the first embodiment, the “vacuum container 70”, the “syringe 80”, and the “vacuum chamber 90” are respectively provided. The other configuration is substantially the same as that of the first embodiment. For this reason, the changed configuration will be mainly described, and the same reference numerals as those in the first embodiment are assigned to the same components as those in the first embodiment.

  First, as shown in FIG. 4 (a), a hole 21 leading to a specific cell (cell to be reinforced) 11 of the honeycomb core 10 is formed in one outer plate 20 of the honeycomb sandwich panel 1 (hole drilling). Installation step), the honeycomb sandwich panel 1 is placed with the holes 21 facing upward. While the diameter dimension of the hole 21 in the present embodiment is set to a sufficiently small value, the flow of the resin 50 into the cell 11 is allowed when a pressure difference greater than or equal to a predetermined value occurs inside and outside the cell 11, When there is no pressure difference between the inside and outside of the cell 11, the inflow of the resin 50 into the cell 11 is prevented.

  Next, as shown in FIG. 3 and FIG. 4, the lower surface of the figure is opened in the peripheral region of the hole 21 formed in the outer plate 20 of the honeycomb sandwich panel 1, and two holes (70a, 70B) are provided on the upper surface. Further, the specific space surrounded by the outer plate 20 and the vacuum container 70 is made airtight by covering with a vacuum container 70 as a covering material and disposing a sealant 71 around the covered portion (covering and sealing step). . The shape and area of the region covered with the vacuum vessel 70 (the region surrounding the hole 21) can be appropriately determined according to the shape of the outer plate 20, the position, size, number, and the like of the holes 21. As shown in FIG. 4A, the vacuum container 70 is provided with an insertion hole 70 a for inserting the needle 81 of the syringe 80 and a connection port 70 b connected to the vacuum chamber 90.

  Next, as shown in FIGS. 3 and 4, a syringe 80 is prepared as a resin reservoir filled with a liquid resin 50 therein, and the needle 81 of the syringe 80 is inserted into the insertion hole 70a of the vacuum container 70 (resin Reservoir process). In the resin reservoir step, the space between the needle 81 and the insertion hole 70a is sealed with a sealant or the like. Further, a not-shown stopper is sandwiched between the piston 82 of the syringe 80 and the flange 83 so that the piston 82 of the syringe 80 is not lowered by the vacuum pressure in the next evacuation step.

  Next, as shown in FIGS. 3 and 4, a vacuum chamber 90 is connected to the connection port 70 b of the vacuum vessel 70 through a vacuum tube 72, and air from the specific space and the cell 11 is used using the vacuum chamber 90. Is discharged (evacuation), and the pressure in the specific space and the cell 11 is set to a predetermined vacuum pressure (for example, 760 Torr) (evacuation step). In the evacuation step in the present embodiment, the inside of the vacuum chamber 90 is evacuated in advance using a predetermined vacuum pump, and the vacuum vessel 70 and the vacuum chamber 90 are connected in a state where a predetermined on-off valve is closed. After that, this on-off valve is opened to perform evacuation.

  Next, as shown in FIG. 4B, the stopper of the syringe 80 is removed, and the piston 82 is lowered by the vacuum pressure in the specific space, whereby the resin 50 in the syringe 80 is injected into the specific space. At this time, since the pressure in the specific space and in the cell 11 are both set to the vacuum pressure, there is no pressure difference between the inside and outside of the cell 11, and the surface tension acts on the resin 50. Does not flow into the cell 11.

  Next, an open / close valve for introducing air (not shown) of the vacuum chamber 90 is opened to cause atmospheric pressure to act on the resin 50 injected into the specific space, so that the air is passed through the hole 21 as shown in FIG. Then, the resin 50 is caused to flow into the cell 11 (resin inflow step), and the infused resin 50 is cured (resin curing step). Then, after confirming the completion of the curing of the resin 50, the vacuum tube 72 and the syringe 80 are removed from the vacuum container 70, the vacuum container 70 is removed from the outer plate 20, and excess resin adhering to the surface of the outer plate 20 is removed. Thereafter, the remaining cells 11 are filled with resin in the same procedure, and it is confirmed that the resin 50 is filled and reinforced in all the cells 11 to be reinforced, and the operation is finished.

  In the reinforcing method according to the embodiment described above, a hole 21 communicating with the cell 11 to be reinforced of the honeycomb core 10 of the honeycomb sandwich panel 1 is formed in one outer plate 20, and a region around the hole 21 is defined. The specific space covered with the vacuum vessel 70 and surrounded by the outer plate 20 and the vacuum vessel 70 is brought into an airtight state. Then, air is discharged from the specific space and the cell 11 to set the pressure in the specific space and the cell 11 to a predetermined vacuum pressure, and a liquid resin 50 is injected into the specific space, and the atmospheric pressure is applied to the resin 50. By acting, the resin 50 flows into the cell 11 and is cured.

  Accordingly, since the liquid resin 50 is allowed to flow into the vacuumed cell 11 to be cured, the entire cell 11 can be reliably filled with the resin 50 and the formation of voids in the cell 11 can be prevented. be able to. As a result, it is possible to prevent a reduction in strength and quality of the product after reinforcement.

  Further, in the reinforcing method according to the embodiment described above, the reinforcing can be performed after the outer plate 20 is bonded to the honeycomb core 10 and the honeycomb sandwich panel 1 is manufactured. Therefore, the conventional method described with reference to FIG. The problem of smoothness of the outer plate and the cracking of the filler that occurred when the reinforcing method (method of bonding or heat-curing the outer plate after filling the cell with the filler) was adopted at once. Can be solved. As a result, it is possible to prevent a decrease in strength and quality of the product and an increase in aerodynamic resistance.

  Further, in the reinforcing method according to the embodiment described above, since “vacuum container 70” is adopted as the covering material and “injector 80” is adopted as the resin reservoir, the covering sealing process and the resin can be performed in a small space. A reservoir step can be performed. Therefore, even if the panel size is relatively small, the reinforcement work can be easily performed. Further, since the “vacuum chamber 90” that is relatively easy to carry is employed in the evacuation process, there is an advantage that the evacuation work (and thus the reinforcement work) can be performed without restrictions on the place.

<Repair method for honeycomb sandwich panel>
Next, a method for repairing the honeycomb sandwich panel according to the embodiment of the present invention will be described with reference to FIGS. 5 and 6. In the present embodiment, a pin formed on one outer plate 20 of a honeycomb sandwich panel 1 having a honeycomb core 10 and a fiber-reinforced resin composite outer plate 20 bonded to both surfaces of the honeycomb core 10. A method of repairing the hole 22 by filling the resin will be described.

  First, as shown in FIG. 5 (a), a heating lamp 2 is arranged in the vicinity of a pinhole 22 formed in the outer plate 20 of the honeycomb sandwich panel 1, and the surrounding area of the pinhole 22 using this heating lamp 2 is arranged. Is heated, the air in the cells 11 of the honeycomb core 10 adjacent to the pinhole 22 is expanded, and a part thereof is discharged (heating step).

  Next, as shown in FIG. 5B, a resin dam 40 is formed as a resin reservoir using a sealant on the outside of the pinhole 22 with the pinhole 22 facing upward, and a liquid dam is formed inside the resin dam 40. Resin 50 is stored (resin storing step). In the resin reservoir step, a resin inflow hole 41 is formed in advance at the bottom of the resin dam 40, and the resin inflow hole 41 is closed with a seal film. Further, the resin inflow hole 41 of the resin dam 40 is disposed so as to be adjacent to the pinhole 22, and the sealant 42 is disposed around the resin dam 40 so that the space surrounded by the resin dam 40 and the outer plate 20 is airtight. And Note that the heating process is continued while the resin reservoir process is being performed.

  Next, the seal film that closes the resin inflow hole 41 provided in the resin dam 40 is pierced with a needle or the like (hole drilling step). When the hole drilling process is performed, the temperature inside and outside the cell 11 is the same, so there is no pressure difference inside and outside the cell 11 and the diameter of the pinhole 22 is very small. 50 is not filled into the pinhole 22 through the resin inflow hole 41.

  Next, heating by the heating lamp 2 is stopped and the peripheral region of the pinhole 22 is cooled, thereby generating a pressure difference between the inside and outside of the cell 11 of the honeycomb core 10 adjacent to the pinhole 22 (cooling step). Then, the resin 50 in the resin dam 40 is filled into the pinhole 22 through the resin inflow hole 41 due to the pressure difference between the inside and outside of the cell generated by this cooling process (resin filling process). In addition, since the resin is easily dropped only by filling the resin 50 only in the pinhole 22, in the resin filling process, the resin larger than the pinhole diameter is formed inside the portion of the outer plate 20 where the pinhole 22 is formed. It is preferable that the resin 50 filled in the pinhole 22 is bonded to the inner surface of the outer plate 20 by forming a lump.

  Here, the principle of the resin filling process will be described. Since the resin filling rate into the pinhole 22 (and the cell 11) in the resin filling step is proportional to the thermal expansion coefficient of the air in the cell 11, the temperature in the cell 11 is adjusted in the heating step by adjusting the temperature in the cell 11. By adjusting the thermal expansion coefficient, the resin filling rate into the pinhole 22 can be set to a desired value. Table 1 shows the thermal expansion coefficient of air when the air at room temperature (about 27 ° C.) is heated to 40 ° C. to 100 ° C.

  For example, when the temperature in the cell 11 is set to 40 ° C. in the heating process, the thermal expansion coefficient of the air in the cell 11 is 1.05 according to Table 1, and the volume of the air in the cell 11 is compared with the volume at room temperature. About "5%". Therefore, when the temperature in the cell 11 is cooled from 40 ° C. to room temperature in the cooling process, the volume of air in the cell 11 contracts by about “5%” compared to the volume at 40 °, and accordingly the cell The air pressure in 11 will drop. The resin 50 is filled into the pinhole 22 (and the cell 11) due to the volume shrinkage and the air pressure drop caused by the cooling of the air in the cell 11, and the filling rate is about “5%” which is equal to the volume shrinkage rate. It becomes. When the temperature in the cell 11 is set to 100 ° C. in the heating process, it can be seen from Table 1 that the coefficient of thermal expansion is 1.25 and the resin filling rate is about “25%”.

  When the resin filling process is completed, the resin 50 filled in the pinhole 22 (and the cell 11) is cured while the resin dam 40 is left at the position (resin curing process). Thereafter, it is confirmed whether or not the resin 50 is cured, and the operation is finished. If the resin 50 has a low viscosity, the excess resin filled in the pinholes 22 may fall to the lower part of the panel, so that the honeycomb sandwich panel 1 is turned upside down after the resin filling process is finished.

  In the repair method according to the embodiment described above, the resin dam 40 is provided outside the pinhole 22 formed in the outer plate 20 of the honeycomb sandwich panel 1, and the liquid resin 50 is stored in the resin dam 40. The resin 50 is adjacent to the pinhole 22 with the space 40 therebetween, and the space surrounded by the resin dam 40 and the outer plate 20 is airtight. In addition, after the area around the pinhole 22 is heated to expand the air in the cell 11 of the honeycomb core 10 adjacent to the pinhole 22 once, the area around the pinhole 22 is cooled to remove the air in the cell 11. A difference is caused between the pressure and the pressure of the air outside the cell 11 (atmospheric pressure).

  A resin inflow hole 41 is formed in a specific portion of the resin dam 40 (a portion adjacent to the pinhole 22), so that the resin 50 in the resin dam 40 can be moved into the pinhole 22 by a pressure difference between the inside and outside of the cell 11. And the resin 50 is cured to close the pinhole 22. Therefore, since the pinhole 22 can be closed without using a “patch” as in the prior art, it is possible to prevent the quality of the product from deteriorating and to prevent the product from increasing in weight and aerodynamic resistance.

  In the repair method according to the embodiment described above, the resin 50 is filled in a state where the outer plate 20 in which the pinholes 22 are formed is arranged on the upper side, and if necessary, the honeycomb sandwich panel 1 is filled after the resin filling. Although an example in which it is turned upside down has been shown, as shown in FIG. 6, the resin 50 may be filled in a state where the outer plate 20 in which the pinholes 22 are formed is previously disposed below.

  That is, as shown in FIG. 6A, the outer plate 20 in which the pinhole 22 is formed is disposed below, and the surrounding area of the pinhole 22 is heated by the heating lamp 2 disposed in the vicinity of the pinhole 22. By this, the air in the cell 11 of the honeycomb core 10 adjacent to the pinhole 22 is expanded, and a part thereof is discharged (heating process). Next, as shown in FIG. 6B, the resin dam 40 is disposed in the vicinity of the pinhole 22, and the resin inflow hole 41 of the resin dam 40 and the pinhole 22 are connected by the resin introduction pipe 43. The liquid resin 50 is stored inside (resin storing step). At this time, the connection portion between the resin inflow hole 41 and the resin introduction tube 43 and the connection portion between the pinhole 22 and the resin introduction tube 43 are closed with a sealant 42 to form an airtight state.

  Next, the seal film closing the resin inflow hole 41 of the resin dam 40 is pierced with a needle or the like (hole drilling step). Then, by stopping the heating by the heating lamp 2 and cooling the peripheral region of the pinhole 22, a pressure difference is generated inside and outside the cell 11 of the honeycomb core 10 adjacent to the pinhole 22 (cooling step). Then, the resin 50 stored in the resin dam 40 is filled into the pinhole 22 through the resin inflow hole 41 and the resin introduction pipe 43 (resin filling process), and the resin 50 is cured (resin curing process).

  Further, in the repair method according to the embodiment described above, an example in which the peripheral region of the pinhole 22 is heated using the “heating lamp 2” is shown. However, the means for heating the peripheral region of the pinhole 22 is not limited to this. It is not limited to. For example, after the entire panel is housed in a “heating and isothermal furnace” and the area around the pinhole 22 is heated, the resin dam 40 and the resin inflow hole 41 are formed in the “heating and isothermal furnace” It is also possible to take out the panel from the “heating thermostat” and cool the surrounding area of the pinhole 22 to fill and cure the resin 50.

  In the repair method according to the embodiment described above, an example in which the resin reservoir process is performed “after” the heating process has been shown. When a resin 50 having a viscosity) is employed, the resin reservoir process can be performed “before” the heating process.

  If the resin reservoir process is performed “before” the heating process in this way, the resin dam installation work in a situation where the outer plate 20 is heated becomes unnecessary, so that the burden on the operator can be reduced. In addition, the air in the cells 11 of the honeycomb core 10 adjacent to the pinholes 22 is expanded by the heating process and discharged from the pinholes 22 and discharged as bubbles in the resin 50 in the resin dam 40. Can be observed. Accordingly, it is possible to easily recognize the pressure balanced state inside and outside the cell 11 in the heating process (the state in which the bubbles are not discharged), so that it is possible to determine the start time of the next process (cooling process). is there.

DESCRIPTION OF SYMBOLS 1 Honeycomb sandwich panel 10 Honeycomb core 11 Cell 20 Outer plate 21 Hole 22 Pinhole 30 Bagging film (coating material)
35 Resin inflow hole 40 Resin dam (resin reservoir)
41 Resin inflow hole 50 Resin 70 Vacuum container (coating material)
80 Syringe (resin reservoir)

Claims (2)

A method for repairing pinholes formed in the outer plate of a honeycomb sandwich panel having a honeycomb core and a fiber reinforced resin composite outer plate bonded to both sides of the honeycomb core,
Providing a resin reservoir on the outside of the honeycomb sandwich panel so as to surround the pinhole with the pinhole on the upper side, storing a liquid resin in the resin reservoir and covering the pinhole with the resin;
A heating step of expanding the air in the cells of the honeycomb core adjacent to the pinhole by heating a peripheral region of the pinhole, and discharging a part of the air;
A cooling step that causes a pressure difference between the inside and outside of the honeycomb core adjacent to the pinhole by cooling a peripheral region of the pinhole following the heating step;
Due to the pressure difference between the inside and outside of the cell generated by the cooling step, the tree in the resin reservoir

A resin filling step of filling the pinhole with fat through a resin inflow hole;
A resin curing step of curing the resin filled in the pinhole;
A method for repairing a honeycomb sandwich panel. A method for repairing pinholes formed in the outer plate of a honeycomb sandwich panel having a honeycomb core and a fiber reinforced resin composite outer plate bonded to both sides of the honeycomb core,
A heating step of heating a peripheral region of the pinhole to expand air in the cells of the honeycomb core adjacent to the pinhole and discharging a part thereof;
A sealed space forming step of covering and sealing the pinhole from the outside of the outer plate to form a sealed space;
A resin reservoir step of providing a resin reservoir in which liquid resin is accumulated outside the sealed space;
A cooling step of cooling the surrounding area of the pinhole heated in the heating step to decompress the inside of the cell;
A resin filling step of providing a hole from the resin reservoir to the pinhole, and filling the pinhole with the resin in the resin reservoir due to a pressure difference between the cell generated in the cooling step and the atmosphere;
A resin curing step of curing the resin filled in the pinhole;
A method for repairing a honeycomb sandwich panel.

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