JPH09142572A - Fiber reinforced resin container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dispense with the change of an ancillary electric circuit and reduce the container cost and meet the replacing demand against existing containers, by achieving the light weight container by use of electric conductive reinforcing fiber like carbon fiber and at the same time, keeping the linear characteristic of an electrostatic capacity type liquid volume sensor. SOLUTION: This container is provided with an inner layer container 1 and a liquid volume sensor 20 constituted of a sensor electrode plate 3 fitted to the outer peripheral side of the inner container 1 and sensor terminal 10A getting in contact with the liquid in the container. And the container is reinforced by winding up carbon fiber 5, 6, 8, 9 on the outer periphery. The liquid volume in the inside can be informed on the basis of the electrostatic capacity corresponding to the liquid volume between the liquid 10 contained in the inner layer container 1 and the sensor electrode plate 3. The sensor terminal 10A and the innermost carbon fiber 5 are connected to each other in short circuit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lightweight and high-strength container mainly used as a container for storing liquids in aircrafts and ships, and more particularly to an improvement in a container using a fiber reinforced synthetic resin.

[0002]

2. Description of the Related Art As containers for storing liquids and the like in aircrafts and ships, containers made of synthetic resin have hitherto been used in order to satisfy the requirements of light weight and high strength. For example, JP-A-57-114479 discloses a container having a structure in which an inner layer of a thermoplastic synthetic resin is integrally bonded with a honeycomb core as a reinforcing layer. Further, in order to further increase the strength, it is also possible to wind a reinforcing fiber around the outer periphery, for example, JP-A-61-1.
Japanese Patent Laid-Open No. 30036 and Japanese Patent Laid-Open No. 64-35174 also disclose a container which is wound for strengthening. This structure will be exemplified later.

By the way, there are various means for knowing the remaining amount of the stored liquid (in most cases, drinking water) in such a container, and one of such methods is to obtain a certain degree of conductivity (general drinking water). There is a capacitance type that is applied in the case of a stored liquid having a certain degree. For example, Japanese Patent Laid-Open No. 6-
In Japanese Patent No. 26907, two long electrode plates fixed so as to face each other are suspended and held in a fluid to increase or decrease the fluid layer interposed between the two electrode plates according to the increase or decrease of the fluid amount. A "level detection device" is disclosed in which the amount of fluid is known from the electrostatic capacitance between the two electrode plates that changes accordingly. FIG. 5 is a block diagram of the electric circuit disclosed in the proposal (the explanation is omitted), and (6 ′) in the figure corresponds to the above-mentioned fluctuating capacitance. Note that, as in this example, in addition to a circuit in which an AC signal wave having a constant frequency and a constant amplitude is applied and the capacitance (hence, the amount of liquid) is known from the response level, the capacitance can be determined by the oscillation condition of the oscillation circuit. A circuit configuration in which the liquid amount is known from the change in the oscillation frequency by connecting to the circuit is generally known.

The structure of the liquid amount sensor unit for taking out the remaining liquid amount as a change in capacitance is as shown in FIGS. 2 to 4, that is, the liquid is used as one electrode and the liquid on the outer peripheral side of the container is The capacitance of the capacitor formed by the electrode plate facing the outer surface is monitored, and the change in the facing area that increases or decreases according to the increase or decrease in the amount of liquid is detected as a change in the capacitance to determine the remaining amount of liquid. Known configurations are known and are widely applied to cylindrical containers for horizontal use. The present invention also
The present invention relates to an improvement in a container structure provided with a liquid amount sensor unit having such a form, and is particularly aimed at improving the liquid remaining amount detection accuracy.

The structure of the conventional container of this type shown in FIGS. 2 to 4 will be described below. In the figure, reference numeral (1)
Is a thermoplastic synthetic resin inflation molded thickness 0.5
It is a thin film hollow inner layer container (inner liner). A reinforcing layer (4) made of fiber reinforced synthetic resin (eg, epoxy impregnated glass fiber cloth) is provided on the outer periphery of the inner layer container (1). Here, an electrode layer having a predetermined mesh shape that constitutes a liquid quantity sensor unit (20) at a predetermined portion between the two.
(3) The (mesh) has insulating films (2, 2) on both sides and is interposed to serve as one electrode forming the capacitor (C1).

That is, as shown in the side view of FIG. 2, a leaf-shaped electrode layer (3) is formed on one side of the side cylindrical surface of the container in which the width is wide in the center in the height direction and narrows in the vertical direction. ) Is provided, and the shape of the electrode (3) is formed so that the liquid volume inside the container and the electrode area below the liquid surface are proportional.
In order to connect the electrode layer (3) to the outside, one end of the electrode layer (3) is
A rod-shaped sensor terminal (3A) connected and fixed to (3) is provided with the other end protruding outward. (2A) is an insulating tube for the sensor terminal (3A).

The other electrode of the capacitor (C1) corresponds to a liquid such as drinking water stored inside the container. Since this internal liquid is electrically connected to the outside, a sensor terminal is provided on the bottom of the container. (10A) is provided. This sensor terminal (1
(0A) is made of a conductive material and is fixed to the container with one end protruding inward from the bottom of the container so that it can contact the liquid (10) contained in the inner container (1) and the other end protruding outside the container. Has been done. With the above configuration, the capacitance of the capacitor (C1)
(c1) increases or decreases according to the height of the contained internal liquid, and is directly proportional to the residual liquid amount as shown in the graph of FIG. 4 (b).

A filament (5: reinforcing fiber) is wound around the outer circumference of the reinforcing layer (4) with the electrode layer (3) interposed therebetween in order to further enhance the rigidity of the container, and a filament (5: reinforcing fiber) 6) is continuously and densely wound in a helical winding, and a honeycomb core (7) formed by bonding a number of hollow hexagonal columns using a non-metallic thin plate with a thickness of about 4 mm such as FRP to form a honeycomb shape (7 ) Is further wound, the filament (8) is wound in a helical winding, and the filament (9) is wound in a hoop winding, and then the whole is heated and cooled to solidify each part, and the fiber-reinforced resin container shown as an example. Is completed.

In the above-mentioned filament winding method used for a water tank or the like, conventionally, a reinforcing filament having a low conductivity such as glass fiber is used. A linear electric output corresponding to the amount of internal liquid was obtained only by converting (c1) into a voltage by the circuit shown in FIG. 5 or other appropriate circuit (21).

[0010]

By the way, it is conceivable to use a lighter and stronger carbon fiber as the above-mentioned reinforcing filament, but in this case, the function of the liquid amount sensor portion described above is hindered. Will end up. That is, since the carbon fiber has good conductivity, the wound carbon fiber layer itself functions as a kind of electrode plate, and a new capacitor element is formed between the carbon fiber and the liquid inside. FIG.
In (a), a capacitor (C2) is formed between the inner carbon fiber (filament (5)) and the outermost surface of the inner liquid (10) as shown by the broken line, and the carbon fiber (5) A capacitor (C3) is also formed between the electrode layer (3) and the electrode layer (3).
After all, what connected both capacitors (C2, C3) in series is
It will be connected in parallel with the capacitor (C1) that has been set up for capacitance measurement.

Here, the combined capacitance value (c2 / c3 / (c2 + c3)) of both capacitors (C2, C3) also changes with the increase of the internal liquid, but the change is as shown in FIG. 4 (c). It is not a linear change as illustrated in the graph. When carbon fiber is used for the filament (5), the total capacitance value (ct ') obtained by combining all the above capacitor elements also has no linearity as shown in the graph of Fig. 4 (d). I will end up. This means that if the conventional subsequent circuit is connected as it is, the true residual liquid amount and the indicated value of the measuring means are deviated from each other, and the accurate residual liquid amount cannot be known.

As a countermeasure, the above-mentioned capacitance (ct ')
Although it is conceivable to provide a correction circuit for electrically correcting the irregular change curve of 1), it is not preferable because the circuit becomes significantly complicated and the cost increases. In addition, it is difficult to use for replacing the conventional fiber-reinforced resin container because the incidental electric circuit must be changed at the same time. Furthermore, the correction circuit must add different correction characteristics depending on the volume and shape of the fiber-reinforced resin container, which complicates the manufacturing process.

The present invention has been made in consideration of the above circumstances, and the conventional capacitance type circuit for detecting liquid capacity is used as it is, while using highly conductive carbon fiber or the like as a reinforcing filament. The purpose was to propose a new fiber-reinforced resin container that has been carefully handled so that it can be used.This enables fiber-reinforced plastics to be made even lighter and more rigid without changing the accessory circuit. A resin container can be provided.

[0014]

In order to achieve the above object, in the present invention, an inner layer container (1), a sensor electrode plate (3) provided on the outer peripheral side of the inner layer container (1), and It is equipped with a liquid volume sensor part (20) consisting of a sensor terminal (10A) that comes into contact with liquid, and is reinforced by winding carbon fiber (5,6,8,9) around the outer periphery of the inner container (1) In the fiber-reinforced resin liquid container in which the internal liquid volume is known based on the electrostatic capacitance corresponding to the liquid volume between the liquid stored in (10) and the sensor electrode plate (3), the sensor terminal (10A ) And the innermost carbon fiber (5) among the carbon fibers are short-circuited.

Further, one end of the inner layer container (1) of a thin film hollow body made of a thermoplastic synthetic resin and the liquid (10) contained in the inner layer container (1) are arranged so as to be in contact with the other end to the outside. A sensor terminal (10A) made of a conductive material that is drawn out and a conductor of a predetermined shape that is sandwiched between insulators (2, 2) at a predetermined location on the outer periphery of the inner layer container (1) for measuring liquid volume. Sensor plate
(3) and a reinforcing layer made of reinforced synthetic resin formed by winding conductive reinforcing fibers (5, 6, 8, 9) on the outside, and solidifying the whole by heating and cooling. In a fiber-reinforced resin container, short-circuit terminals may be placed during the winding process of the above-mentioned reinforcing fibers (5,6).
By winding the reinforcing fiber (6) with the interposition of (11), the short-circuit terminal (11) is brought into contact with the innermost reinforcing fiber (5) and the tip portion (11a) of the short-circuit terminal (11) is ) Is projected to the outside and fixedly held, and the short-circuit terminal (11) and the sensor terminal (10A) are conductively connected.

[0016]

EXAMPLES The fiber-reinforced resin container of the present invention will be described below in more detail with reference to the accompanying drawings based on examples.
1 (a) to 1 (e) are views according to an embodiment of the present invention, in which (a) is a side view of an embodiment container (30A) and (b) is a carbon fiber (6). Short-circuit terminal for electrical connection (short-circuit) with the outside
(11) Enlarged cross-sectional view of the mounting part, (c) is a diagram showing the connection of each part of the liquid capacity measurement circuit, (d) is its equivalent circuit diagram,
(e) is a graph showing capacitance change and electric output in Examples.

The main construction of the embodiment is the same as that of the fiber-reinforced resin container (30) shown in FIGS. 2 and 3, and the short-circuit terminal (1
The only difference is that 1) is added. Below,
The description of the overlapping parts will be omitted or briefly described. In the figure, reference numeral (1) is an inner layer container (inner liner), and (4) provided on the outer periphery thereof is a reinforcing layer made of fiber reinforced synthetic resin,
(3) is a capacitance type liquid volume sensor section (2
The insulating film (2, 2) is arranged on both sides of the mesh-shaped electrode layer having a predetermined shape which serves as one of the electrodes constituting (0). Electrode layer
The shape of (3) is exactly the same as that described above, and it has a leaf-like shape with one side of the container on one side of the side wall that is wide in the center in the height direction and narrows in the vertical direction. The shape of (3) is formed so that the liquid volume inside the container is proportional to the electrode area below the liquid surface.

Reference numeral (3A) is a rod-shaped sensor terminal for connecting the electrode layer (3) to the outside, one end of which is connected and fixed to the electrode layer (3) and the other end of which is provided so as to project outward. There is. (2
A) is an insulating tube for the sensor terminal (3A). (10A) on the bottom surface of the container is a sensor terminal for electrically connecting the internal liquid such as drinking water stored inside the container, which is the other electrode (equivalent) of the capacitor (C1) to the outside, and is made of a conductive material. ,
One end projects inward so that it can contact the liquid (10) contained in the inner layer container (1), and the other end projects and is fixed to the outside of the container. These configurations are the same as the conventional ones, and the capacitance (c1) of the capacitor (C1) has a linear relationship with the internal liquid amount (see FIG. 1 (e)).

In this way, the carbon fiber (5) as a filament is wound around the outer periphery of the reinforcing layer (4) wound with the electrode layer (3) partially interposed (in order to increase the rigidity of the container). The carbon fiber (6) is wound around the base of the short-circuit terminal (11) from above. This short-circuit terminal (11) is made of copper or other conductive material and has one end formed on a disk-shaped pedestal with a stud protruding from the center, and a carbon fiber (6) filament wind (winding). In the process), the carbon fiber (6) is wound so that the carbon fiber (6) passes through the upper surface of the base while the bottom surface of the base is attached to the carbon fiber (5). The carbon fiber (6) is wound by helical winding.

This carbon fiber (6) not only reinforces the container, but also serves to fix the short-circuit terminal (11) located in the center of the container. Secure to each other and at the same time securely connect to each other. By this method of winding the short-circuit terminal (11) inside, the short-circuit terminal (11) can be arranged and fixed in the same process as in the past, and since the filament (6) is not divided, there is no decrease in the rigidity of the container. , The mounting of the short-circuit terminal (11) is firm and the electric connection is surely made.

The subsequent steps are the same as in the conventional method, and the honeycomb core (7) made of FRP is further wound, and the carbon fiber (8) (helical winding) and the carbon fiber (9) (hoop winding) are wound again. After turning, after solidifying each part by heating and cooling the whole, the short-circuit terminal (11) and the sensor terminal (3A) are short-circuited with a harness or the like to make a fiber-reinforced resin container
(30A) is completed. In this container, as shown in the equivalent circuit diagram of Fig. 1 (d), the capacitance value (C2), which had changed according to the liquid amount in the container in the previous explanation, became invalid due to a short circuit, and the sensor terminal The (combined) capacitance (Ct) seen from (3A) and the sensor terminal (10A) is always a constant capacitance (C3) and a capacitance value (linearly changing according to the remaining amount of liquid ( Since it is a parallel circuit of C1) and the linearity is maintained as shown in FIG. 1 (e), the correction is only a subtraction of a constant, and the correction circuit can be very simple. If it is a pointer type reading circuit, it is only necessary to change the scale marking.

As described above, the fiber-reinforced resin container (30A) of the embodiment is a conductive reinforcing filament (carbon fiber).
However, since the capacitance value of the liquid amount sensor unit for detecting the remaining amount of internal liquid changes linearly corresponding to the remaining amount of liquid, a correction circuit is unnecessary or extremely simple. . Therefore, even if the container is replaced with a container using an insulating reinforcing filament such as glass fiber to reduce the weight, the incidental circuit does not need to be changed or is slight, resulting in cost reduction.
In addition, there is an advantage that it can be used as it is for the repair / replacement demand of the existing container using the insulating filament.

In the embodiment, the short-circuit terminal (11) is provided at the center of the side surface, but it may be provided at any part of the container as long as the innermost layer of carbon fiber allows winding and contact. In the present invention, the point is that the sensor terminal (10A) in contact with the liquid inside the container and the sensor electrode plate (3) provided on the outer periphery of the inner layer container (1) are first wound further on the outer peripheral side. It is sufficient if the structure is such that the conductive container reinforcing filament (5) such as carbon fiber is short-circuited. Regardless of how the reinforcing fiber is wound, it may be appropriately adopted depending on the required performance of the container. Carbon fiber is preferably used as the conductive container reinforcing filament, but other composite materials are also highly conductive and have a certain degree or more of influence on the capacitance of the liquid amount sensor section. The present invention is similarly effective for the above. It should be noted that some powders can be stored in the above-mentioned container and the remaining amount can be known by a capacitance type.

[0024]

According to the present invention, an inner layer container, a sensor electrode plate provided on the outer peripheral side of the inner layer container, and a liquid amount sensor section composed of a sensor terminal in contact with the liquid inside the container are provided. Fiber reinforced resin that is reinforced by winding carbon fiber around the outer circumference and that knows the internal liquid volume based on the electrostatic capacity corresponding to the liquid volume between the liquid stored inside the inner layer container and the sensor electrode plate. In the liquid container, since the sensor terminal and the innermost carbon fiber among the carbon fibers are short-circuited, conductive carbon fibers are used for reinforcement to achieve weight reduction, and at the same time, originally The linearity of the sensor unit can be maintained by invalidating the newly formed capacitor that adversely affects the characteristics of the liquid amount sensor unit. This has the remarkable effect that it is not necessary to change the accessory electric circuit, the cost of the container can be reduced, and the demand for replacement with the conventional container is also possible.

Further, the inner layer container of a thin film hollow body made of a thermoplastic synthetic resin, and the sensor terminal made of a conductive material, one end of which is arranged to be in contact with the liquid contained in the inner layer container and the other end of which is drawn out to the outside. And a sensor electrode plate for measuring the amount of liquid, which is made of a conductor of a predetermined shape and is sandwiched between insulators at a predetermined portion on the outer periphery of the inner layer container, and further, a conductive reinforcing fiber is wound on the outside. In a fiber-reinforced resin container in which a reinforcing layer made of a reinforced synthetic resin is arranged, and the whole is solidified by heating and cooling, by winding a fiber by interposing a short-circuit terminal during the winding process of the reinforcing fiber, If the short-circuit terminal and the innermost fiber are brought into contact with each other and the tip of the short-circuit terminal is projected to the outside and fixedly held, the short-circuit terminal and the sensor terminal are conductively connected to each other to form a fiber-reinforced resin container. , The same effect as the above invention Of course the obtained further adding the shorting terminal can firmly fixed to reliable connections, yet nor lead to decrease in rigidity of the container. There is almost no increase in the manufacturing process and it contributes to the price reduction.

[Brief description of the drawings]

FIG. 1 is a side view (a) of a fiber-reinforced resin container which is an embodiment of the present invention, a sectional view (b) of the same, and a circuit diagram (c) for explaining internal liquid volume detection. , Its equivalent circuit
6D is a graph (e) showing the output of the detection circuit and the like.

FIG. 2 (a) is a side view showing an example of a conventional fiber-reinforced resin container.

FIG. 3 is an enlarged cross-sectional view (a) of a main part of the container of FIG. 2 and a schematic circuit diagram (b) illustrating detection of an internal liquid amount.

FIG. 4 is an electrical equivalent circuit diagram of a conventional fiber-reinforced resin container.
(a), a graph showing a change in capacitance between the electrode plate for measurement and the internal liquid (b), a graph showing a change in capacitance caused by the use of a conductive filament depending on the amount of the liquid (c), and a composite at the sensor terminal It is a graph (d) showing a change in capacitance.

FIG. 5 is a circuit block diagram showing an example of a known circuit for capacitance type liquid amount detection.

[Explanation of symbols]

 (1)… Inner container, (2,2)… Insulator, (3)… Sensor plate, (5,6,8,9)… Reinforcing fiber (carbon fiber), (10)… Liquid, (10A) … Sensor terminal, (11)… Short circuit terminal, (11a)… Tip, (20)… Liquid amount sensor section.

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[Procedure amendment]

[Submission date] March 4, 1996

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Figure 2

[Correction method] Change

[Correction contents]

FIG. 2 is a side view showing an example of a conventional fiber-reinforced resin container.

[Procedure amendment 2]

[Document name to be amended] Drawing

[Correction target item name] Fig. 1

[Correction method] Change

[Correction contents]

FIG.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical indication // B29L 22:00

Claims (2)

[Claims] 1. A liquid amount comprising an inner layer container (1), a sensor electrode plate (3) provided on the outer peripheral side of the inner layer container (1), and a sensor terminal (10A) in contact with the liquid inside the container. It is equipped with a sensor part (20) and is reinforced by winding carbon fiber (5,6,8,9) around the outer periphery, and the liquid (10) stored inside the inner layer container (1) and the sensor electrode plate ( 3) In the fiber-reinforced resin liquid container in which the internal liquid volume is known based on the electrostatic capacity corresponding to the liquid volume between, the sensor terminal (10A) and the innermost carbon fiber ( 5) A fiber-reinforced resin container characterized in that and are short-circuited. 2. An inner layer container (1) of a thin film hollow body made of a thermoplastic synthetic resin, and a liquid contained in the inner layer container (1).
A sensor terminal (10A) made of a conductive material, one end of which is arranged so that it can come into contact with the other end and the other end of which is pulled out to the outside, and an insulator (2, 2) is attached to a predetermined portion of the outer circumference of the inner layer container (1) A sensor electrode plate (3) consisting of a conductor of a predetermined shape sandwiched in between for measuring the liquid amount
And a reinforcing layer made of reinforced synthetic resin formed by winding conductive reinforcing fibers (5,6,8,9) on the outside, and the whole is solidified by heating and cooling. In the container, by winding the reinforcing fiber (6) with the short-circuit terminal (11) interposed during the winding process of the reinforcing fiber (5, 6), the short-circuit terminal (11)
And the innermost reinforcing fiber (5) are in contact with each other and the short-circuit terminal
A fiber-reinforced resin container in which a tip portion (11a) of (11) is projected outward and fixedly held, and the short-circuit terminal (11) and the sensor terminal (10A) are conductively connected.