JP2010032478A - Forming regimes monitoring device and method of fiber-reinforced plastic, and manufacturing method of fiber reinforced plastics therewith - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a good compact with thickness as a designed value, by monitoring continuously, temporarily and correctly impregnation of liquid object and forming regimes of a fiber-reinforced substrate formed through thermoset process in forming of FRPs. <P>SOLUTION: The forming regime monitoring device and the monitoring method of fiber-reinforced plastics are characterized by measuring the thickness of the fiber enhancement substrate, such that, in impregnation of liquid object into plate-like enhancement fiber substrate arranged in a form block installed in a heating oven and thermoset process, each displacement measuring means arranged on a first plane of the enhancement fiber substrate and a first plane of the form block is used to alleviate influences of thermal deformation of a fixing means of the displacement measuring means, the form block, and the displacement measuring means. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a continuous thickness monitoring apparatus and a monitoring method for fiber reinforced plastics according to the molding conditions of fiber reinforced plastics, particularly liquid impregnation in a heating furnace, and thermosetting conditions.

  Carbon fiber reinforced plastic (hereinafter referred to as CFRP) using carbon fiber or glass fiber as reinforced fiber, fiber reinforced plastic (hereinafter referred to as FRP) represented by glass fiber reinforced plastic (hereinafter referred to as GFRP) is lightweight and has high durability. Since it has, it is applied as various components, such as a motor vehicle and an aircraft.

  As a typical method for producing these FRPs, an autoclave molding method using a prepreg is known. In such a molding method, an intermediate base material called a prepreg in which a reinforcing fiber is impregnated with a matrix resin in advance is stacked on a mold, and then vacuum-sealed with a film material and heated and pressurized in an autoclave to form a composite material. . However, since the matrix resin impregnated in the prepreg is a thermosetting resin containing a curing agent, the curing reaction proceeds gradually, and the usable time is short and a freezer storage facility is required. There was a limitation in using a matrix resin of a curable resin.

  Therefore, in recent years, the RTM molding method has attracted attention as a method that can be molded more easily than the conventional autoclave molding using a prepreg. Resin Transfer Molding (hereinafter referred to as RTM) molding method is a method in which a reinforcing fiber base material (a laminate of reinforcing fiber sheets shaped in advance) is placed in a mold and placed in a heating furnace, and then a matrix is formed on the reinforcing fiber base material. This is a method of injecting resin and curing the matrix resin by heating. In this RTM molding method, the main resin and the curing agent may be mixed just before the injection of the matrix resin, and there is no need to worry about the progress of the curing reaction. Further, since the matrix resin can be stored at room temperature by dividing the resin into the main resin and the curing agent, a large-scale freezing storage facility is not required. In addition, there is an advantage that large equipment such as an autoclave is not required at the time of molding.

  On the other hand, compared with autoclave molding using a prepreg, the RTM molding method tends to increase the thickness variation of the molded member including the reinforcing fiber base, particularly in the matrix resin injection step. For this reason, the injection amount of the matrix resin corresponding to the thickness change amount of the entire molding member is grasped, and when the thickness of the entire molding member reaches the target thickness, the matrix resin injection is stopped and injected. It is necessary to cure the matrix resin. However, it is difficult to visually grasp the thickness of the molded member impregnated with the matrix resin in the injection process and the curing process of the matrix resin in the heating furnace. As a result, even if the molded part in the matrix resin injection process and curing process in the heating furnace has a thickness different from the design value, check until the matrix resin has been cured and the molded part has been demolded. Therefore, there is also a problem that it is impossible to prevent the thickness of a part of the molded member from being defective and the entire product from being wasted.

  In particular, in a molding process in which a large amount of material is used for impregnation as in the case of aircraft wing molding, manufacturing loss due to defective thickness becomes large. For this reason, the amount of change in the thickness of the molded member is continuously measured in the heating furnace, and the amount of change in the thickness of the molded member that changes over time due to the injection and curing of the matrix resin is constantly grasped. That is very important.

  As a method for accurately measuring the thickness of a measurement object without being affected by temperature changes, a reference sample with small thermal expansion (small deformation with respect to temperature changes) in the heating atmosphere and the thickness change amount are measured. A method of measuring the thickness of a sample to be measured based on the difference in displacement of each detection rod by placing two detection rods connected to a differential transformer in contact with the respective samples. Known (Patent Document 1).

  In this measurement method, a device is devised in which the deformation of the two detection rods with respect to the temperature change is offset by using a differential transformer, and the thickness of the sample to be measured can be accurately measured.

  However, in this method, since it is necessary to arrange a sample serving as a reference with a small deformation with respect to a temperature change, sample preparation for measurement operation becomes complicated. Moreover, since it is necessary to make a detection rod contact a measuring object, there exists a problem of damaging a measuring object. Furthermore, since the measurement configuration uses a differential transformer, the distance between the reference sample and the sample to be measured is limited, and it is difficult to measure an arbitrary point.

  As another method for accurately measuring the thickness of the measurement object without being affected by the temperature change, a single displacement sensor using a laser beam is scanned to obtain a sample and a reference whose thickness is to be measured. By measuring the height (thickness) of each sample in a non-contact state with each sample and calculating the difference between the measured values, the influence of deformation on the temperature change of each sample can be removed and accurately A method for measuring the thickness of a measurement object is known (Patent Document 2).

  According to this method, since the measurement object is not contacted, there is no damage to the measurement object, but it is necessary to place a reference sample of the same material and thickness as the measurement object. The sample preparation becomes complicated. In addition, a displacement sensor that emits a laser beam has a problem that measurement cannot be performed in an environment heated to a temperature higher than that because the heat resistance temperature of the optical components inside the sensor, such as a lens, is about 40 ° C. at most. It was.

  Another method for accurately measuring the thickness of an object to be measured without being affected by changes in temperature is to place a laser light source in a room temperature atmosphere and to split the laser beam with a beam splitter placed in a heated atmosphere. A method of measuring the displacement of a measurement object using an interference fringe of a laser beam reflected from a reference position and a measurement object position is known (Patent Document 3).

  In this method, since the laser light source is arranged in a room temperature atmosphere, there is no problem in terms of heat resistance of the optical component, and since the measurement configuration is a non-contact, there is no damage to the measurement object. However, when the laser beam reflected in the heating atmosphere enters the light receiving element placed in the room temperature atmosphere, it is affected by the change in the refractive index due to the difference in air temperature, so it accurately measures the displacement of the measurement object. I could not do it.

As described above, there has been no technique for measuring the thickness of the measurement object easily and accurately without being affected by the temperature change in the heated atmosphere without damaging the measurement object.
Japanese Patent No. 2759770 JP 2001-289619 A JP 2003-302358 A

  When measuring the change in thickness of a part during molding using the monitoring method according to the prior art, the influence of the change in thickness due to temperature change on the measured value is inevitable, and damage to the part during molding The thickness of the member being molded in a heating furnace with a temperature change is limited. It cannot be measured accurately and easily.

  The object of the present invention is to solve such a problem, that is, in the molding of FRP, the molding condition of the member being molded, particularly the thickness of the member being molded, is continuously affected without being affected by temperature changes. Monitoring is to obtain a good molded body having a thickness as designed.

In order to achieve the above object, the present invention has one of the following configurations.
(1) An operation for processing a signal from the displacement measuring means, comprising a molding die and a plurality of sets of measuring means comprising a conductor and a displacement measuring means facing the conductor in a non-contact manner inside the heating furnace. A molding condition monitoring device for fiber-reinforced plastic, characterized by comprising a processing means.
(2) A reinforcing fiber base is disposed on the mold, and at least one set of the measuring means is disposed on the mold, and at least one set of the measuring means is also disposed on the reinforcing fiber base. The molding condition monitoring apparatus for fiber-reinforced plastic according to (1), characterized in that
(3) The fiber reinforced plastic molding condition monitoring device according to any one of (1) and (2), wherein the displacement measuring means is measured by electrical or magnetic means.
(4) The fiber-reinforced plastic molding condition monitoring device according to any one of (1) to (3), wherein the displacement measuring means constituting the measuring means is fixed via a fixing means. .
(5) The fiber-reinforced plastic molding according to any one of (1) to (4), wherein the fixing means for fixing the displacement measuring means is fixed to a single fixing member. Condition monitoring device.
(6) For the reinforcing fiber substrate disposed on the mold provided in the heating furnace,
While disposing a conductor on the first surface of the reinforcing fiber base and disposing the first displacement measuring means in the heating furnace so as to face the conductor in a non-contact manner,
A conductor is disposed on the first surface of the mold that is in contact with the second surface of the reinforcing fiber substrate, and the second displacement measuring means is disposed in the heating furnace so as to face the conductor in a non-contact manner. Placed in
The displacement amount in the thickness direction of the reinforcing fiber base is measured using the first displacement measuring means, and the displacement amount in the thickness direction of the mold is measured using the second displacement measuring means. A molding condition monitoring method for fiber-reinforced plastic, characterized in that.
(7) The amount of displacement obtained from the first displacement measuring means and the amount of displacement obtained from the second displacement measuring means are corrected by the arithmetic processing means, and the thickness direction of the reinforcing fiber substrate is corrected. The method of monitoring the molding status of the fiber-reinforced plastic according to (6), characterized in that the amount of displacement is used.
(8) The difference between the displacement amount obtained from the first displacement measuring means and the displacement amount obtained from the second displacement measuring means is calculated by the arithmetic processing means, and the thickness direction of the reinforcing fiber substrate The method of monitoring the molding state of the fiber-reinforced plastic according to (6), characterized in that the amount of displacement of
(9) The value of the displacement obtained from the first displacement measuring means and the value of the displacement obtained from the second displacement measuring means are corrected by the arithmetic processing means, and then after the correction processing. The molding condition monitoring method for fiber reinforced plastics according to (6), wherein the difference between the respective displacement amounts is calculated by the calculation processing means.
(10) A distance between each of the first displacement measuring means and the conductor disposed opposite thereto, and a distance between the second displacement measuring means and the conductor disposed opposite thereto. After the step of adjusting to the same distance before heating in the heating furnace, the method includes the step of starting measurement of the displacement amount in the thickness direction of the reinforcing fiber substrate or the displacement amount in the thickness direction of the mold. The molding condition monitoring method for a fiber-reinforced plastic according to any one of (6) to (9), characterized in that it is characterized.
(11) The step of measuring the thickness of the reinforcing fiber base in advance before heating the heating furnace, the thickness measurement value, and the reinforcing fiber obtained during and after heating of the heating furnace The fiber-reinforced plastic molding according to any one of (6) to (10), wherein the arithmetic processing means calculates the thickness of the reinforcing fiber base from the amount of displacement in the thickness direction of the base. Status monitoring method.
(12) A method for producing fiber reinforced plastic in which a reinforced fiber base material is impregnated with a liquid, and the impregnation step and the curing step are controlled using the molding state monitoring method according to any one of (6) to (11). A method for producing a fiber-reinforced plastic, characterized by being made.

  In the present invention, the “molding die” may be a molding die that forms a closed space (molding cavity), and may form a closed space (molding cavity) by combining a plurality of molds used in normal RTM molding. Alternatively, a molding die made of a film material in which a reinforcing fiber base material is disposed on a lower die and a closed space (molding cavity) is formed by a sealing material and a film may be used. As a material for the covering film (bagging film) for forming the closed space, a polyethylene terephthalate film or the like is preferable from the viewpoint of heat resistance. The present invention is applied to a step of impregnating and curing a liquid material in a reinforcing fiber base disposed in such a closed space.

  In the present invention, the term “reinforcing fiber base material” refers to a reinforced fiber fabric, knitted fabric, braided fabric, a laminate of reinforcing fiber fabrics such as paper made from short fibers of reinforcing fibers, or a reinforced fiber as a triaxial woven fabric. An aggregate with a certain thickness of reinforcing fibers. The reinforcing fiber contained in the reinforcing fiber base is usually a fiber bundle in which thousands to tens of thousands of single fibers are aggregated.

  In addition, the shape of the reinforcement fiber base material which this invention makes object should just have a plate-shaped part in at least one part. Although all of the reinforcing fiber bases may be plate-shaped, the portion that is impregnated with the liquid material and that monitors the molding state may be plate-shaped. The reinforcing fiber base material is a laminate of reinforcing fiber materials or a single body, and may be a curved surface, a polygonal surface, or a surface with irregularities. In the present invention, the “first surface of the reinforcing fiber substrate” refers to a surface opposite to the reinforcing fiber substrate surface that is in direct contact with the mold, and “the second surface of the reinforcing fiber substrate”. "Surface" refers to the surface of the reinforcing fiber substrate surface that is in direct contact with the mold.

  As the “reinforcing fiber” in the present invention, high-strength, high-modulus fiber such as carbon fiber, glass fiber, and aramid fiber can be used.

  In the present invention, the “first surface of the mold” refers to a surface that is in direct contact with the second surface of the reinforcing fiber substrate.

  In the present invention, the “displacement measuring means” refers to a sensor head for measuring displacement, and the “first displacement measuring means” is opposed to a conductor disposed on the reinforcing fiber substrate in a non-contact manner. The “second displacement measuring means” refers to a sensor head that is disposed in a non-contact manner and opposed to the conductor disposed on the mold. In the present invention, the “conductor” means an electrically conductive object having a resistance value of 4 kΩ or less with respect to the ground (GND) in a closed loop circuit including a displacement measuring means. In addition, it is preferable that the conductor is grounded in that it is less susceptible to electrical noise.

  In the present invention, “measuring means” is defined as a pair of the “conductor” and “displacement measuring means” that faces the conductor in a non-contact manner.

  In the present invention, “arranging the conductor on the first surface of the reinforcing fiber base” means that the conductor is not only disposed in contact with the first surface of the reinforcing fiber base. It also includes disposing a bagging film or a metal member between the body and the first surface of the reinforcing fiber substrate.

  In the present invention, the “heating furnace” refers to a heating furnace having a space in which a temperature operation of 40 ° C. or higher is performed in a range where the air temperature is 5 ° C. or higher and 200 ° C. or lower. As heating means, circulating heated air, controlling the heater output to heat the air so that the temperature in the heating furnace becomes a set value, and heated by a hot air heating method using heated air as a medium or by a heating medium Heating medium heating system that supplies heat energy to the object to be heated directly from the heated mold, and induction heating that heats the electric coil close to the object to be heated by the induced current (eddy current) obtained on the surface of the object to be heated Although there is a method, and the like is not particularly limited in the present invention, a hot air heating method can be preferably used from the viewpoint of easy installation of the mold and the reinforcing fiber base.

  The “liquid body” used in the present invention is only required to have fluidity as a whole, and a thermoplastic resin, a mere liquid such as water, or a liquid containing a solid content (for example, a particulate substance or the like is dispersed). May be included). In FRP molding, a thermosetting resin is mainly assumed, but includes not only liquids at room temperature but also those that flow at the molding temperature, such as thermoplastic resins. As the thermosetting resin, there are epoxy resin, phenol resin, melamine resin, etc., but epoxy resin is most preferable from the viewpoint of dimensional stability after curing, water resistance, chemical resistance, high electrical insulation, etc. Used.

  In the above description, the impregnation of the liquid material in the present invention is based on a process in which a fiber reinforced base material is placed in a mold and a liquid material (liquid resin) is injected from the outside. In addition to this process, a partially impregnated prepreg, which is a sheet-like reinforcing fiber substrate partially impregnated with a liquid resin in advance, and a resin film that is solid at room temperature are placed in a mold and laminated and raised. Also included are those in which the resin softens or melts and soaks between the reinforcing fibers or between the reinforcing fiber layers when warmed.

  ADVANTAGE OF THE INVENTION According to this invention, the thickness of the reinforced fiber base material which changes according to the impregnation and thermosetting of a liquid can be continuously and simply monitored in a heating atmosphere without being affected by temperature changes. And when producing a FRP molded object using the monitoring method of the present invention, the state of impregnation of the liquid material into the reinforcing fiber base material and the thickness of the member during molding that changes according to thermosetting can be simplified and It becomes possible to monitor reliably.

  As a result, early detection of abnormalities in the matrix resin injection and thermosetting processes and product approval standards can be more reliably satisfied based on the measured thickness of the part being molded in the production of FRP molded products. It becomes. Furthermore, based on the measured thickness value of the member being molded, it is possible to inject matrix resin, automate the stop operation, etc., and reduce manpower.

  In particular, in addition to the effects described above, it is possible to relate the production conditions of fiber reinforced plastics, which could not be known accurately in the past, and the thickness change of the reinforcing fiber base material. Thus, it is possible to obtain an effect that a good FRP molded product having a thickness as designed can be obtained.

  Hereinafter, preferred embodiments of a molding condition monitoring apparatus and monitoring method for fiber reinforced plastic according to the present invention will be described with reference to the drawings. In addition, the case where a flat base material is used as the reinforcing fiber base material will be described as an example. In addition, this invention is not restricted to these examples, For example, a reinforced fiber base material may have a polygonal surface.

  FIG. 1 is a side view schematically showing an embodiment of a fiber reinforced plastic molding condition monitoring apparatus according to the present invention using a non-contact type displacement sensor as a displacement measuring means. The mold 4 is disposed in the heating furnace 5 having a temperature change, and the reinforcing fiber base 3 is disposed on the first surface 41 of the mold 4. The temperature in the heating furnace 5 is controlled between room temperature and about 200 ° C. according to the respective processes of raising the temperature of the reinforcing fiber base 3, injecting and stopping the liquid material, and thermosetting. In addition, normal temperature means about 5 to 30 degreeC.

  The second surface 32 of the reinforcing fiber base 3 is disposed so as to be in close contact with the first surface 41 of the mold 4. The conductor 2S is arranged in the heating furnace 5 so as to be in close contact with the first surface 31 of the reinforcing fiber base 3, and the displacement measuring means 1S is arranged in the heating furnace 5 so as to face the conductor 2S in a non-contact manner. Has been. Further, the conductor 2R is disposed in the heating furnace 5 so as to be in close contact with the first surface 41 of the mold 4, and the displacement measuring means 1R is disposed in the heating furnace 5 so as to face the conductor 2R in a non-contact manner. Has been.

  Although not shown in FIG. 1, the displacement measuring means 1S and 1R are connected to a processing amplifier having a signal processing function disposed outside the heating furnace 5 via a cable, and the conductors 2S and 2R Is also connected to the ground terminal of the processing amplifier having the signal processing function via a cable.

  The displacement measuring means 1S and 1R are preferably sensors that measure displacement by electric or magnetic action. For example, in the electric type, a capacitance type displacement sensor that detects displacement from a change in capacitance by forming an electric field between the displacement measuring means 1S (1R) and the conductor 2S (2R), in the magnetic type, displacement measurement is performed. It is most preferable to use an eddy current displacement sensor or the like that forms a magnetic field between the means 1S (1R) and the conductor 2S (2R) and detects displacement from the impedance change.

  As the displacement measuring means 1S and 1R, if an optical displacement sensor, such as a laser displacement sensor that measures displacement by irradiating a laser beam, is used, as described above, thermal damage to optical components inside the sensor occurs. In addition to poor measurement accuracy, the sensor itself is more likely to fail. For this reason, when an optical sensor is used, a cooling facility for the sensor itself must be provided separately. Therefore, in order to provide a low-cost measurement method, as described above, an electric or magnetic displacement is used. Most preferably, a sensor is used.

  When an electric sensor is used for the displacement measuring means 1S, the same electric sensor is used for the displacement measuring means 1R, and when the magnetic sensor is used for the displacement measuring means 1S, the displacement measuring means 1R is the same. It is most preferable to use a magnetic type sensor from the viewpoint of minimizing the difference of the sensor with respect to the measuring ability. Furthermore, it is most preferable that the displacement measuring means 1S and 1R use the same type of sensor.

  The displacement measuring means 1S and 1R are arranged via the fixing means 6. FIG. 1 shows that only the displacement measuring means 1R is arranged via the fixing means 6. Although the solid means of the displacement measuring means 1S is not shown, the displacement measuring means 1S is also subject to displacement measurement. It is fixed by the same fixing means as the fixing means 6 of the means 1R.

  Note that it is most preferable to use the same fixing means as the fixing means 6 for the displacement measuring means 1S and 1R from the viewpoint of considering the thermal expansion of the fixing means 6 itself. For example, a material that is difficult to thermally expand, such as stainless steel, may be used, and fixing means having the same size and shape may be used. By using all the same fixing means, it is not necessary to use a material having a particularly low linear expansion coefficient, for example, an expensive material such as invar or titanium, and a low-cost measuring method can be provided.

  Most preferably, the displacement measuring means 1S and 1R fixing means 6 have a mechanism for moving the displacement measuring means 1S and 1R in the thickness direction of the reinforcing fiber base 3. This is because the thickness of the reinforcing fiber base 3 arranged on the mold 4 before the injection of the liquid material varies, and depending on the thickness of the reinforcing fiber base 3, the tip surface of the displacement measuring means 1S and This is because it is necessary to set and adjust the distance to the conductor 2S to be substantially constant. For example, as shown in FIG. 1, a micrometer head 6A or the like is installed on the fixing means 6, and the displacement measuring means 1S or 1R is disposed at the tip of the micrometer head 6A, so that only the knob of the micrometer head 6A is rotated. Thus, the displacement measuring means 1S or 1R can be easily moved in the thickness direction of the reinforcing fiber base 3.

  Further, regarding the moving mechanism such as the micrometer head 6A provided in the fixing means 6 of the displacement measuring means 1S or 1R, the micrometer head 6A itself also undergoes thermal expansion due to heating in the heating furnace 5, and the displacement measuring means 1S or 1R It can cause displacement measurement errors. For this reason, when the fixing means 6 having the same micrometer head 6A is used, the influence of the thermal expansion and contraction of the micrometer head 6A itself can be relatively canceled by the difference calculation described later, and the reinforcing fiber base 3 Most preferred is that the amount of change in thickness can be measured more accurately.

  By this moving mechanism, the distance between the tip surface of the displacement measuring means 1S and the conductor 2S and the distance between the tip surface of the displacement measuring means 1R and the conductor 2R can be adjusted. Each distance is preferably about half of the measurement range of the displacement measuring means 1S or 1R. For example, when the measurement range of the displacement measuring unit 1S is 0 to 5 mm, the moving mechanism is adjusted so that the distance between the distal end surface of the displacement measuring unit 1S and the conductor 2S is 2 to 3 mm. Most preferably, all the fixing means 6 installed in the heating furnace 5 are adjusted so as to have substantially the same distance.

  It is preferable that one fixing means 6 for fixing the displacement measuring means 1S or 1R is prepared for each displacement measuring means 1S or 1R. This is to make it easier to move the displacement measuring means 1S or 1R to an arbitrary position to be measured when measuring the thickness change amount of the reinforcing fiber base 3 using the displacement measuring means 1S and 1R.

  The fixing means 6 for fixing the displacement measuring means 1S or 1R is preferably fixed on one member, and particularly fixed on the first surface 41 of the mold 4 as shown in FIG. Most preferred. Since the molding die 4 also thermally expands as the temperature rises in the heating furnace 5 and heat shrinks as the temperature falls in the heating furnace 5, the fixing means 6 is placed on the first surface 41 of the molding die 4. In other words, the influence of the thermal expansion and contraction of the mold 4 brings the same amount of displacement measurement error to the displacement measuring means 1S and 1R. For this reason, by the difference calculation mentioned later, the influence of the thermal expansion or thermal contraction of the shaping | molding die 4 can be canceled relatively, and the thickness variation | change_quantity of the reinforced fiber base material 3 can be measured more correctly.

  The conductors 2S and 2R may be a plate-like electrically conductive material, and are most preferably a metal typified by iron or aluminum. It is preferable that the conductors 2S and 2R have the same thickness from the viewpoint of thermal expansion in a heated state, and a thickness of about 2 to 10 mm is preferable. Furthermore, the same material is most preferable. The conductors 2S and 2R may be made of a material having a small linear expansion coefficient, for example, an expensive material such as invar or titanium, but is not limited from the viewpoint of providing a low-cost measuring method, and SUS303 that is easy to process is used. Stainless steel such as SUS304 is preferably used. The displacement measuring means 1S or 1R is preferably arranged so that the parallelism between the conductor 2S and the displacement measuring means 1S or the parallelism between the conductor 2R and the displacement measuring means 1R is within 3 °.

  In the conductor 2S, the area of the surface facing the displacement measuring means 1S may be equal to or larger than the area of the tip of the displacement measuring means 1S, and is most preferably 1.2 times or more the area of the tip of the displacement measuring means 1S. Similarly, in the conductor 2R, the area of the surface facing the displacement measuring means 1R may be equal to or larger than the area of the tip of the displacement measuring means 1R, and 1.2 times or more the area of the tip of the displacement measuring means 1R is the most. preferable.

  Further, when considering a normal line perpendicular to the tip surface from an arbitrary position on the tip surface of the displacement measuring means 1S, each perpendicular line intersects the surface of the conductor 2S facing the displacement measuring means 1S. It is most preferable to arrange the conductor 2S and the displacement measuring means 1S. Similarly, when considering a normal in the normal direction to the tip surface from an arbitrary position on the tip surface of the displacement measuring means 1R, each perpendicular intersects the surface of the conductor 2R facing the displacement measuring means 1R. As described above, it is most preferable to dispose the conductor 2R and the displacement measuring means 1R.

  The distance between the distal end surface of the displacement measuring means 1S and the facing surface of the conductor 2S facing the displacement measuring means 1S may be arbitrarily set, but the measurement accuracy decreases as the distance increases, and the displacement Since the measuring means 1S becomes large in size, it is not practically preferable. Therefore, the distance between the distal end surface of the displacement measuring unit 1S and the facing surface of the conductor 2S facing the displacement measuring unit 1S is preferably 0.5 mm or more and 10 mm or less. Furthermore, in order to make the measurement accuracy higher, it is preferable to arrange at a distance as close as possible to the maximum value of the change in thickness of the reinforcing fiber base 3, and most preferably from 0.5 mm to 5 mm. preferable. The same applies to the distance between the distal end surface of the displacement measuring means 1R and the opposing surface of the conductor 2R facing the displacement measuring means 1R.

  Next, when using the monitoring apparatus configured as described above, the distance between the tip surface of the displacement measuring means 1S measured by the displacement measuring means 1S and the conductor 2S, or the displacement measurement measured by the displacement measuring means 1R. A preferred embodiment relating to the calculation processing of the distance between the tip surface of the means 1R and the conductor 2R will be described with reference to FIG.

FIG. 3 shows a conceptual diagram of a signal processing flow in the processing amplifier. As described above, the displacement measuring means 1S and 1R are connected to a processing amplifier (not shown) having a signal processing function arranged outside the heating furnace 5 via a cable, and from the displacement measuring means 1S and 1R, Each electric signal input into the processing amplifier is subjected to input processing such as signal amplification processing within the processing amplifier, and is output from the processing amplifier as a voltage output signal _Vout .

For example, when the distance between the distal end surface of the displacement measuring means 1S and the conductor 2S is d _A0 , the output voltage V _out from the processing amplifier is V _a0 . Ideally, as indicated by a broken line 3A in FIG. 3, a linear relationship V _out = k * d + α (k: constant, α: constant) is established between the actual distance d and the output voltage. Although it is preferable to do this, this linear relationship does not actually hold. For example, as shown by the solid line 3B in FIG. 3, the linear relationship often does not hold (this is called a linearity error). Therefore, linear correction processing (calculation processing 1) is performed inside the processing amplifier.

More specifically, for example, as shown in FIG. 3, when the distance between the tip surface and the conductor of the displacement measuring means is _{d A0,} the output is a voltage _V out _{= V a0,} the output voltage _{V a0,} V _A0 = k _* is converted into the output voltage _{V A0} calculated from _{d A0,} and outputs as _{V out.} Next, a difference calculation process is performed as the calculation process 2. This will also be described with reference to FIG. As described above, between the output voltage _Vout corrected by the calculation process 1 and the distance d between the distal end surface of the displacement measuring means and the conductor, as indicated by a solid line 3C in FIG. A linear relationship is established. Here, at the same time, if the output voltage after being input from the displacement measuring means 1S and being subjected to the arithmetic processing 1 is V _A1 and the output voltage being input from the displacement measuring means 1R and being after the arithmetic processing 1 is V _B , the distal end surface and the distance of the conductor 2S measuring means 1S, and the tip surface and the distance between the conductor 2R displacement measuring means 1R, _{respectively,} is recognized as d A1, _{d B.} Thereafter, at the same time after the lapse of the same time, the output voltage after being input from the displacement measuring means 1S and subjected to the arithmetic processing 1 is V _A1 ′, and the output voltage after being input from the displacement measuring means 1R and after the arithmetic processing 1 is V _{If B} ′, the distance between the distal end surface of the displacement measuring means 1S and the conductor 2S and the distance between the distal end surface of the displacement measuring means 1R and the conductor 2R are recognized as d _A1 ′ and d _B ′, respectively. The

From these facts, the amount of change Δd _A1 = d _A1 ′ −d _A1 between the distal end surface of the displacement measuring means 1S and the conductor 2S when the same time elapses, the distal end surface of the displacement measuring means 1R and the conductor 2R A distance change amount Δd _B = d _B ′ −d _B is expressed, and a calculation process 2 (difference calculation process) is performed as a difference value Δd ₁ = Δd _A1 −Δd _B between the two results. The difference value Δd ₁ obtained in this way is used as the amount of change in the thickness of the reinforcing fiber base 3.

As described above, in the actual measurement, before injecting the liquid material, more preferably before starting the heating of the heating furnace, the output voltage V after being input from the displacement measuring means 1S and subjected to the arithmetic processing 1 an output voltage V _B of after the input processing 1 from _A1 and displacement measuring means 1R, in other words, the tip and the conductive and the distance d _A1 between the tip and the conductor 2S displacement measuring means 1S displacement measuring means 1R If the distance d _B to the body 2R is adjusted to be the same using the micrometer head 6A, that is, if adjusted so that d _A1 = d _B , the amount of change Δd in the thickness of the reinforcing fiber base 3 ₁ = d _A1 ′ −d _B ′, and the calculation process 2 is simplified, which is most preferable.

The following effects (a) to (d) are obtained by the calculation process 2 (difference calculation process) as described above.
(A) The influence of thermal expansion or thermal contraction of each fixing means 6 of the displacement measuring means 1S and 1R can be reduced.
(B) The influence of the temperature characteristics of the displacement measuring means 1S and 1R can be reduced.
(C) The influence of thermal expansion or contraction of the conductors 2S and 2R can be reduced.
(D) The influence of thermal expansion or contraction of the mold 4 can be reduced.
Regarding (d), when the fixing means 6 of the displacement measuring means 1S or 1R are arranged on the first surface 41 of the mold 4 as described above, the mold 4 is molded by thermal expansion. Due to the deformation of the mold 4 in the thickness direction, the displacement measuring means 1S or 1R also moves in the thickness direction of the reinforcing fiber base 3 following the deformation via the fixing means 6, and at the same time, the reinforcing fiber base 3 and the conductor Since 2S and 2R itself also move in the thickness direction of the reinforcing fiber base 3, they are relatively less susceptible to the thermal expansion of the mold 4 and have no significant effect on the thermal expansion or contraction of the mold 4. . However, if the fixing means 6 cannot be arranged on the first surface 41 of the mold 4 due to the problem of the arrangement space and must be fixed on another member, the difference processing is performed. Thus, since the displacement in the thickness direction of the mold 4 can be canceled, the effect on the influence of thermal expansion or contraction of the mold 4 is great.

  The arithmetic processing 1 (straight line correction processing) and arithmetic processing 2 (difference arithmetic processing) described above may be performed within one processing amplifier, or each arithmetic operation may be performed using an individual arithmetic unit such as a personal computer. It may be processed. In this way, the value obtained by the difference process is output as a result.

Result output processing refers to calculation processing while repeating the following operations.
(A) For example, as shown in FIG. 4, the absolute thickness of the reinforcing fiber base 3 at the place where the conductor 2S is disposed is measured in advance with a thickness measuring instrument such as a micrometer (absolute thickness measurement value T ₀ ).
(B) As shown in FIG. 5, the displacement measuring means 1S or 1R is arranged via the fixing means 6, the conductors 2S and 2R are arranged, and the tip surface of the displacement measuring means 1S and the conductor 2S are arranged. distance d _A1, respectively adjusted using the moving mechanism 6A such as micrometers as the distance between the tip surface and the conductor 2R displacement measuring means 1R becomes d _B.
(C) Thereafter, as shown in FIG. 6 (fixing means 6 is not shown), for example, the tip of the displacement measuring means 1S when the thickness of the reinforcing fiber base 3 changes (increases) after a certain period of time, for example. When the distance between the surface and the conductor 2S is d _A1 ′, and the distance between the tip surface of the displacement measuring means 1R and the conductor 2R is d _B ′, the value Δd ₁ = ( Based on d _A1 ′ −d _A1 ) − (d _B ′ −d _B ), the thickness T of the reinforcing fiber base 3 is calculated by an arithmetic expression T = T ₀ −Δd ₁ .

  The result output process may include processing of storing various data, displaying a screen, printing, and the like.

  After the configuration and adjustment as described above, in the state where the displacement measuring means 1S or 1R, the conductor 2S or 2R, and the fixing means 6 are arranged, the molding process of the reinforcing fiber base 3 is performed using the arithmetic processing described above. While starting the continuous monitoring, the heating in the heating furnace 5 is started, and the heating is continued until the predetermined furnace temperature or the surface temperature of the reinforcing fiber base 3 reaches a predetermined temperature.

During this time, the displacement measuring means 1S or 1R and the conductor 2S or 2R, the fixing means 6, the reinforcing fiber base 3, and the mold 4 are mainly deformed due to thermal expansion as the temperature in the heating furnace 5 rises. Occurs. Under such circumstances, the displacement measuring means 1S continuously measures the distance to the conductor 2S in time, and the displacement measuring means 1R also measures the distance to the conductor 2R continuously in time. At the same time, the processing amplifier performs the above-described arithmetic processing 1, arithmetic processing 2, and result output processing to cancel the influence of the temperature change, and then set the thickness T of the reinforcing fiber base 3 alone to T = T _0. It is possible to measure accurately by calculating −Δd ₁ .

  The liquid material is injected into the reinforcing fiber base 3 after the inside of the heating furnace 5 reaches a predetermined temperature and after a predetermined elapsed time. Then, the impregnation of the liquid material shown in the hatched portion 11 in FIG. 1 proceeds according to the impregnation direction D in FIG. FIG. 1 is a schematic diagram during the impregnation of the liquid material, and there is an unimpregnated portion 12 indicating the impregnation of the liquid material. However, when the impregnation of the liquid material is completed, the unimpregnated portion 12 disappears.

In this liquid impregnation process, the thickness of the reinforcing fiber base 3 increases due to the influence of the injected liquid, and accordingly, the conductor 2S on the first surface of the reinforcing fiber base 3 is also measured for displacement. As a result, the distance d _A1 between the distal end surface of the displacement measuring unit 1S and the conductor 2S becomes smaller. Even in this process, the displacement measuring means 1S or 1R and the conductor 2S or 2R, the fixing means 6, the reinforcing fiber base 3, and the molding die 4 are deformed mainly due to thermal expansion. 1. By performing the calculation process 2 and the result output process, the influence of the temperature change due to the temperature rise is canceled, and the thickness T of only the reinforcing fiber base 3 impregnated with the liquid material is accurately calculated as T = It can be measured by calculating T ₀ −Δd ₁ .

In addition, after the liquid material has been impregnated into the reinforcing fiber base 3, the injection of the liquid material is stopped, and then the excess liquid material called bleed is discharged. In the process, since the surplus liquid material is discharged from the reinforcing fiber base 3, the thickness of the reinforcing fiber base 3 decreases, and accordingly, the conductor 2S on the first surface of the reinforcing fiber base 3 also becomes. The distance d _A1 between the distal end surface of the displacement measuring means 1S and the conductor 2S increases compared to immediately before the bleed operation is started.

Even in this process, the displacement measuring means 1S or 1R and the conductor 2S or 2R, the fixing means 6, the reinforcing fiber base 3, and the molding die 4 are deformed mainly due to thermal expansion. 1. By performing the calculation process 2 and the result output process, the influence of the temperature change due to the temperature rise is canceled, and the thickness T of only the reinforcing fiber base 3 impregnated with the liquid material is set to T = T ₀ − It can be measured accurately by calculating Δd ₁ .

Thereafter, the discharge of the surplus liquid material called bleed is stopped, and the temperature of the heating furnace 5 is further increased to a predetermined temperature while maintaining the injection amount of the liquid material impregnated in the reinforcing fiber base 3. This is a process of thermosetting the liquid material impregnated in the reinforcing fiber base 3. In this process, since the liquid material impregnated in the reinforcing fiber base 3 is thermally contracted, the thickness of the reinforcing fiber base 3 impregnated with the liquid is reduced. Along with this, the conductor 2S on the first surface of the reinforcing fiber base 3 also moves away from the tip surface of the displacement measuring means 1S, and the distance d _A1 between the tip surface of the displacement measuring means 1S and the conductor 2S. Becomes larger.

Even in this process, as the temperature in the heating furnace 5 increases, the displacement measuring means 1S or 1R, the conductor 2S or 2R, the fixing means 6, the reinforcing fiber base 3, and the mold 4 are mainly heated. Although deformation due to expansion occurs, by performing the calculation process 1, the calculation process 2 and the result output process, the influence of the temperature change due to the temperature rise is canceled, and the reinforced fiber base impregnated with the liquid material accurately. The thickness T of the material 3 alone can be measured by calculating T = T ₀ −Δd ₁ .

  After the temperature of the heating furnace 5 is further raised to a predetermined temperature, when a predetermined time has elapsed, the thermosetting of the liquid material impregnated in the reinforcing fiber base 3 is completed. Thereafter, through the process of lowering the temperature in the heating furnace 5 to room temperature, the molding of the fiber reinforced plastic is completed.

Even in this process, the temperature in the heating furnace 5 is gradually decreasing, and accordingly, the displacement measuring means 1S or 1R, and the conductor 2S or 2R, the fixing means 6, the reinforcing fiber base 3, the mold In each of 4, deformation due to thermal expansion so far is eased. However, by performing the calculation process 1, the calculation process 2 and the result output process, the thickness T of only the reinforcing fiber base 3 impregnated with the liquid material is accurately measured after canceling the influence of the temperature change due to the temperature drop. Can be measured by the calculation of T = T ₀ −Δd ₁ . Before the temperature of the heating furnace 5 reaches room temperature and the finished fiber reinforced plastic is taken out from the heating furnace 5, the monitoring of the molding state of the reinforcing fiber base 3 is terminated.

  In all the processes as described above, when the molding condition monitoring method according to the present invention is used, the thickness of the reinforcing fiber base 3 can be monitored continuously in time. In addition, it leads to early detection of abnormalities during molding in all the above processes, and by controlling the transition of each process based on the monitored values, it is possible to manufacture fiber reinforced plastic with the thickness as designed. It becomes.

  FIG. 2 is a side view schematically showing another embodiment of the method for monitoring the molding state of the fiber reinforced plastic according to the present invention using a non-contact type displacement sensor as the displacement measuring means. As shown in FIG. 2, a plurality of displacement measuring means 1S and conductors 2S are arranged at positions where the thickness of the reinforcing fiber base 3 is to be measured (FIG. 2 shows an example in which three sets of displacement measuring means 1S and conductors 2S are arranged. It is possible to measure the thickness of the reinforcing fiber base 3 at a plurality of positions at the same time by arranging and performing the above-described arithmetic processing 1, arithmetic processing 2 and result output processing.

[Example 1]
As shown in FIG. 1, in the FRP structure manufacturing process, an iron flat plate-shaped mold 4 having a thickness of 300 mm × 300 mm and a thickness of 5 mm was installed in a heating furnace 5. A mold release treatment is performed on the first surface 41 of the iron mold 4, and a 150 mm × 150 mm flat reinforcing fiber substrate 3 using carbon fibers as a reinforcing fiber of 150 mm × 150 mm is disposed thereon. did. This reinforcing fiber base 3 has a pseudo-isotropic laminated structure, in which 24 carbon fiber fabrics (CZ8431DP, T800 unidirectional fabric manufactured by Toray Industries, Inc.) are laminated. Incidentally, the thickness T ₀ of the reinforcing fiber base 3 was measured using a micrometer (Mitutoyo Corporation model: OMC-150MJ) before being placed on the mold 4 and was 20.642 mm.

  A bagging film was put on the reinforcing fiber base 3 so as to seal the reinforcing fiber base 3. Although omitted in the drawings, a release cloth, a resin diffusion medium, and a metal plate for pressurization are provided between the reinforcing fiber base 3 and the mold 4 or between the reinforcing fiber base 3 and the bagging film. I caught it. After reducing the pressure of the sealed space including the reinforcing fiber base 3 covered with the bagging film with a pump, the conductor 2S is placed on the first surface 31 of the reinforcing fiber base 3 via the bagging file. Displacement measuring means 1S was disposed so as to face it. Further, the conductor 2R is disposed on the first surface 41 of the mold 4 via a bagging film, and the displacement measuring means 1R is disposed so as to face the conductor 2R.

  Displacement measuring means 1S and 1R were disposed about 100 mm apart in the left-right direction in FIG. The displacement measuring means 1S and 1R fixing means 6 were installed on the first surface 41 of the mold 4 respectively. As the fixing means 6, a magnet stand (KANETEC Co., Ltd. model: MB-B) was used. All the connection points of the metal bars constituting the magnet stand were welded.

  As the conductors 2S and 2R, flat metal plates having a thickness of 3 mm and dimensions of 30 mm × 30 mm were used. The material of the metal plate was SUS303. Further, as the displacement measuring means 1S and 1R, capacitance type displacement sensors (Nanotex Corporation 200 ° C. heat resistant electrostatic probe core electrode diameter φ = 11 mm, measurement range: 0 to 5000 microns) were used.

Displacement measuring means 1S and 1R were respectively connected to signal input terminals of channel 1 and channel 2 via a processing amplifier (Nanotex Corporation model: PS-III-2D) via a high-frequency coaxial cable of about 10 m. The conductors 2S and 2R were also connected to the ground terminals (GND terminals) of the channel 1 and the channel 2 with a heat-resistant coated cable (cross-sectional area of 0.75 mm ² ) of about 10 m, respectively.

  The monitor output signal (analog voltage output signal) of each channel was extracted from the processing amplifier. The monitor output signal of each channel was set so that a voltage signal changing from 0 to 10 (V) was output with respect to a change of 0 to 5000 (microns) from the distance between the displacement measuring means and the conductor. However, the output voltage signal has only an accuracy of about 0 to + 2% linearity (that is, output up to 100 microns larger than the actual distance).

  Each monitor output signal was connected to an input signal terminal of an analog controller (Keyence Corporation model: RD-50R) one-to-one with a high-frequency coaxial cable having a length of about 50 cm. Each analog controller has a linearization function for calculating an input signal from the processing amplifier to a preset value. As a result, in the output voltage signal from the processing amplifier, a linearity of about 0 to + 2% is reduced to a linearity of about 0 to + 0.2% (that is, up to 10 microns with respect to the actual distance). It was confirmed that the accuracy could be improved.

  The signal linearized by the analog controller is taken out from the output terminal of each analog controller, and the channel 1 side of the processing amplifier (displacement) is connected to the channel 1 of the recording device (hereinafter referred to as data logger. KEYENCE CORPORATION Model: NR-1000). The output signal from the analog controller to which the signal of the measuring means 1S side) is input was captured. Also, the output signal from the analog controller in which the signal on the channel 2 side (displacement measuring means 1R side) of the processing amplifier is input to the channel 2 of the data logger is taken and the input signal from each analog controller is recorded at a cycle of 10 seconds. The configuration.

Then, using the moving mechanism 6A attached to the fixed unit 6, a distance d _A1 between the tip and the conductor 2S displacement measuring means _1S, and the distance d _B between the tip and the conductor 2R displacement measuring means 1R, The moving mechanism 6A was adjusted so that the voltage display of each analog controller was 5.000 ± 0.010 (V) while observing the voltage display on the front surface of each analog controller so as to approach about 2500 microns. As the moving mechanism 6A, a micrometer head (Mitutoyo Corporation model: MHK-15) was used for both.

  After the arrangement and adjustment of each device as described above, heating in the heating furnace 5 is started from about 20 ° C. to about 70 ° C., and at the same time, the amount of change in the thickness of the reinforcing fiber base 3 by recording with a data logger Started monitoring. Then, after the temperature in the heating furnace 5 reaches about 70 ° C., the temperature is maintained for a certain time, and the matrix resin (from the left of the reinforcing fiber base 3 in FIG. The liquid was started to flow from the left side to the right side, that is, according to the impregnation direction D. An epoxy resin composition was used as the matrix resin.

  After a certain period of time, the matrix resin injection was stopped, the bleed operation was performed, and a part of the injected matrix resin was discharged. Thereafter, the temperature in the heating furnace 5 was raised from about 70 ° C. to about 130 ° C., and the temperature in the heating furnace 5 was kept at about 130 ° C. for a certain period of time to thermally cure the injected matrix resin. Then, after the temperature in the heating furnace 5 was lowered to about 40 ° C., the recording of the data logger was stopped and the monitoring was finished.

In addition to the series of monitoring, the micrometer (Mitutoyo Co., Ltd.) was used immediately before the start of monitoring, immediately before resin injection, immediately before the start of bleed, immediately before the temperature rise from 70 ° C. to 130 ° C. The thickness of the reinforcing fiber base 3 was measured using a model: OMC-150MJ. Thickness measurement accuracy is evaluated by comparing the difference between the thickness immediately before the start of monitoring and the thickness obtained by micrometer measurement at each timing with the monitoring result (result output calculation result) of data logger channel 1. The results are shown in Table 1. From this result, the thickness situation (thickness change amount) of the reinforcing fiber base 3 in a series of molding processes such as liquid impregnation and thermosetting is accurately compared with the micrometer measurement value ΔT _ref specifically. And could be monitored with an error of up to 30 microns.

[Example 2]
Monitoring was performed under the same configuration and conditions as in Example 1, and a differential calculation process for each displacement measurement value recorded at the same time on channel 1 and channel 2 of the data logger was performed on a separately prepared personal computer. In the same manner as in Example 1, in conjunction with a series of monitoring, at the timing immediately before the start of monitoring, immediately before the resin injection, immediately before the start of bleed, immediately before the temperature increase from 70 ° C. to 130 ° C., and immediately before the stop of the monitoring after the temperature decrease is completed. Measure the thickness of the reinforcing fiber base 3 using a meter (Mitutoyo Co., Ltd. model: OMC-150MJ), and evaluate the match between the thickness immediately before the start of monitoring and the difference between the thickness obtained by micrometer measurement at each timing. went. The results are shown in Table 2.

From this result, by performing the differential treatment, the thickness state (thickness change amount) of the reinforcing fiber base 3 in a series of molding processes such as liquid impregnation and thermosetting is determined by the temperature change in the heating furnace 5. It was possible to reduce the influence and to monitor with higher accuracy, specifically, with an error of a maximum of 17 microns compared to the micrometer measurement value ΔT _ref .

[Example 3]
Monitoring was performed under the same configuration and conditions as in Example 2, and a differential calculation process for each displacement measurement value recorded at the same time on channel 1 and channel 2 of the data logger was performed on a separately prepared personal computer. Further, in the same manner as in Example 1, immediately before start of monitoring, the micrometer (Mitutoyo Corporation Model: OMC-150 MJ) with using the results T ₀ of the measurement of the thickness of the reinforcing fiber substrate 3, the A calculation of thickness T = T ₀ −Δd _{1 of} the reinforcing fiber base 3 was carried out on a separately prepared personal computer from the difference calculation result Δd ₁ obtained by the calculation on a separately prepared personal computer. Using the micrometer (Mitutoyo Corporation model: OMC-150MJ) at the timing immediately before resin injection, immediately before the start of bleed, immediately before the temperature rise from 70 ° C. to 130 ° C., and immediately before the stop of the monitoring after the completion of the temperature drop. A butt evaluation with the measured thickness measurement result of the reinforcing fiber base 3 was performed. The results are shown in Table 3.

  From this result, it is possible to reduce the influence of the temperature change in the heating furnace 5 and monitor the absolute thickness of the reinforcing fiber base 3 in a series of molding processes such as liquid impregnation and thermosetting with higher accuracy. did it.

[Reference Example 1] (Confirmation test of difference between individual displacement measuring means and fixing means and temperature effect)
As shown in FIG. 7, the reinforcing fiber base 3 is not disposed on the mold 4 and the conductor 2S is disposed directly on the first surface 41 of the mold 4, and the displacement measuring means 1S and the displacement measuring means 1R are disposed. The displacement data recorded in the channels 1 and 2 of the data logger were measured with the same configuration and conditions as in Example 1 except that the distance in the left and right directions was 30 mm. Table 4 shows the measurement results.

From this result, regardless of the temperature change in the heating furnace 5, the absolute value of the difference Δd ₁ between the measured values of the data logger channel 1 and channel 2 is within 5 microns, and the displacement measuring means 1S and the displacement measuring means 1R It was confirmed that the difference between individuals in the measurement ability and the difference between individuals in the thermal expansion of each fixing means 6 were extremely small.

  The above-described monitoring apparatus and monitoring method for the fiber-reinforced plastic molding of the present invention is a method for manufacturing an FRP structure in which a reinforcing resin substrate is impregnated with a liquid resin and then cured in a heating furnace. Although applied preferably, it is not limited to this as an application object, For example, it can use suitably also in monitoring of the thermal expansion amount of the measuring object arrange | positioned in a heating furnace.

It is a side view which represents typically one Embodiment of the molding condition monitoring method of the fiber reinforced plastic using the displacement measuring means 1S and the displacement measuring means 1R concerning this invention. It is a side view which represents typically one Embodiment of the molding condition monitoring method of the fiber reinforced plastic using multiple displacement measuring means 1S concerning this invention and the displacement measuring means 1R. It is a processing flowchart which shows one Embodiment regarding the calculation method of the measured value of the displacement measuring means 1S and the displacement measuring means 1R concerning this invention. It is a figure showing the image regarding the measurement of the initial thickness of the fiber reinforced base material 3. FIG. It is a figure showing the image of arrangement | positioning structure of a displacement measurement means other before temperature rising of a heating furnace. It is a figure showing the image of arrangement | positioning structure of a displacement measuring means other after the heating start of a heating furnace. It is an image figure showing the evaluation structure which performs a measurement and a calculation process using each displacement measurement means in the state where the reinforcing fiber base material 3 is not arranged on the mold 4.

Explanation of symbols

1S Displacement measuring means 1R Displacement measuring means 2S Conductor 2R facing the displacement measuring means 1S Conductor 3 facing the displacement measuring means 1R Reinforcing fiber substrate 31 First surface 32 of the reinforcing fiber substrate 3 Reinforcing fiber substrate 3 Second surface 4 Molding die 41 First surface 5 of molding die 4 Heating furnace 6 Displacement measuring means fixing means 6A Displacement measuring means moving mechanism 11 Liquid body 12 Unimpregnated portion D of liquid body 11 Liquid body 11 the curve representing the actual correlation between the distance V _out processing amplifier output voltage 3A distance d between the impregnation direction d tip and the conductive surface of the displacement measuring means and the ideal straight line 3B distance d between the output voltage V _out and the output voltage V _out 3C the distance d between the output voltage _{V out} processing amplifier output voltage before correction calculation corresponding to a distance _{V a0} distance _{d A0} between the tip and the conductive surface of the linear _{d A0} displacement measuring means representing a correlation between _{V A0} distance _{d A0} Phase Processing amplifier output voltage d _A1 after the correction calculation The distance d _A1 'between the tip of the displacement measuring means 1S before the start of monitoring and the conductor 2S d _A1 ' The tip of the displacement measuring means 1S after the start of monitoring and the conductor 2S tip distance d _B monitoring before the start of the displacement measuring means 1R tip and conductor 2R distance d _B 'distance V _A1 displacement measuring means 1S tip and conductor 2R displacement measuring means 1R after lapse monitoring starts after t seconds output voltage V _B after processing 1 when the output voltage V _A1 'distance of the tip and the conductor 2S displacement measuring means 1S is d _A1' after processing 1 when the distance d _A1 of the conductors 2S arithmetic processing when the output voltage V _B after processing 1 when the distance d _B of the tip and the conductor 2R displacement measuring means 1R 'distance of the tip and the conductor 2R displacement measuring means 1R is d _B' 1 output voltage Δd _A1 d after Enhancement was measured using a monitoring method according to the result T present invention a process of calculating the ₁ and 'the difference [Delta] d _B d _B between _{d A1'} and the difference [Delta] d ₁ [Delta] d _A1 and [Delta] d _B between the _{d B} 2 (difference operation) absolute thickness T ₀ initial reinforcing fiber base 3, which is measured before heating of the heating furnace 5 absolute thickness T _ref micrometer thickness readings delta _Tref micrometer reinforcing fiber base 3 by the fiber substrate 3 Thickness change of reinforcing fiber base 3 by measurement

Claims (12)

Arithmetic processing means for processing a signal from the displacement measuring means, comprising a molding die and a plurality of sets of measuring means comprising a conductor and a displacement measuring means facing the conductor in a non-contact manner inside the heating furnace. A molding condition monitoring device for fiber reinforced plastic, characterized by comprising. A reinforcing fiber substrate is disposed on the mold, and at least one set of the measuring means is disposed on the mold, and at least one set of the measuring means is disposed on the reinforcing fiber substrate. The molding condition monitoring device for fiber-reinforced plastic according to claim 1, characterized in that it is characterized in that 3. The fiber reinforced plastic molding condition monitoring apparatus according to claim 1, wherein the displacement measuring means is measured by an electric or magnetic means. The fiber reinforced plastic molding condition monitoring device according to any one of claims 1 to 3, wherein the displacement measuring means constituting the measuring means is fixed via a fixing means. The molding condition monitoring device for fiber-reinforced plastic according to any one of claims 1 to 4, wherein the fixing means for fixing the displacement measuring means are fixed together as one fixing member. For the reinforcing fiber substrate placed on the mold provided in the heating furnace,
While disposing a conductor on the first surface of the reinforcing fiber base and disposing the first displacement measuring means in the heating furnace so as to face the conductor in a non-contact manner,
A conductor is disposed on the first surface of the mold that is in contact with the second surface of the reinforcing fiber substrate, and the second displacement measuring means is disposed in the heating furnace so as to face the conductor in a non-contact manner. Placed in
The displacement amount in the thickness direction of the reinforcing fiber base is measured using the first displacement measuring means, and the displacement amount in the thickness direction of the mold is measured using the second displacement measuring means. A molding condition monitoring method for fiber-reinforced plastic, characterized in that. The displacement amount obtained from the first displacement measuring means and the displacement amount obtained from the second displacement measuring means are corrected by the arithmetic processing means, and the displacement amount in the thickness direction of the reinforcing fiber base The molding condition monitoring method for fiber reinforced plastic according to claim 6, wherein: The difference between the displacement amount obtained from the first displacement measuring means and the displacement amount obtained from the second displacement measuring means is calculated by the arithmetic processing means, and the displacement amount in the thickness direction of the reinforcing fiber substrate is calculated. The molding condition monitoring method for fiber reinforced plastics according to claim 6, wherein: The displacement amount value obtained from the first displacement measuring means and the displacement amount value obtained from the second displacement measuring means are corrected by the arithmetic processing means, and then the respective displacements after the correction processing are corrected. 7. The method of monitoring the molding status of fiber reinforced plastic according to claim 6, wherein the difference in quantity is calculated by the calculation processing means. A distance between each of the first displacement measuring means and the conductor disposed opposite to the first displacement measuring means, and a distance between the second displacement measuring means and the conductor disposed opposite to the first displacement measuring means. After the step of adjusting to the same distance before heating, the step of starting the measurement of the displacement amount in the thickness direction of the reinforcing fiber base or the displacement amount in the thickness direction of the mold The molding condition monitoring method of the fiber reinforced plastic according to any one of claims 6 to 9. A step of measuring the thickness of the reinforcing fiber base in advance before heating the heating furnace, the thickness measurement value, and the reinforcing fiber base obtained during and after heating of the heating furnace. The method for monitoring the molding status of a fiber reinforced plastic according to any one of claims 6 to 10, wherein the thickness of the reinforcing fiber base is calculated by the calculation processing means from the amount of displacement in the thickness direction. It is a manufacturing method of the fiber reinforced plastic which makes a reinforced fiber base material impregnate a liquid substance, Comprising: An impregnation process and a hardening process are controlled using the molding condition monitoring method in any one of Claims 6-11. A method for producing a fiber-reinforced plastic characterized.

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