A capacitive mold flow sensor system embedded in a mold and its implementation method

Abstract

This invention discloses a capacitive mold flow sensor system and its implementation method embedded in a mold. The system includes metal plates embedded in an upper and lower mold, forming parallel plate capacitors with each metal plate corresponding to its installation position. An energizing circuit is used to conduct electricity to the metal plates. A capacitance information converter is connected to the metal plates and measures the capacitance value of the parallel plate capacitors formed by the energized metal plates. An information processing module is connected to the capacitance information converter. The capacitance information converter measures the capacitance value of each parallel plate capacitor, and the information processing module generates capacitance value change curves for all parallel plate capacitors after a material medium is poured into the mold cavity. This invention constructs a mold flow sensor system for measuring the flow direction of the material medium within the mold cavity. By analyzing the sequence of capacitance changes in parallel plate capacitors at different positions, the flow direction and position of the material medium can be determined. This system features high detection accuracy and long service life.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of sensors, in particular to a mold-embedded capacitive mold flow sensor system and implementation method. BACKGROUND

[0002] High pressure resin transfer molding process, referred to as HP-RTM molding process, refers to the use of high pressure to mix and inject resin into a vacuum sealed mold pre-laid with fiber reinforced materials and pre-embedded inserts, through resin flow filling, impregnation, curing and demolding, to obtain a composite product forming process. The HP-RTM process cannot directly observe the resin flow in the mold cavity due to its closed molding characteristics, making process optimization difficult and trial and error costly. Mold flow monitoring through sensors is an important means to achieve HP-RTM process defect prediction and optimize process parameters.

[0003] The existing mold flow monitoring method mainly uses sensors embedded in the fiber preform, which collects data returned by the sensor through a special data acquisition device, and processes the data through data analysis software to convert the returned data into resin flow state information.

[0004] Currently, mold flow monitoring uses sensors embedded in the fiber preform. Due to long-term high-temperature working environment, the current sensor has a short service life and consumes quickly, and may also have a serious impact on product performance. SUMMARY

[0005] The present application aims to provide a mold-embedded capacitive mold flow sensor system and implementation method to solve the technical problem of low sensor survival rate, fast consumption, and possible serious impact on product performance in the prior art.

[0006] To solve the above technical problems, the present application specifically provides the following technical solutions:

[0007] A mold-embedded capacitive mold flow sensor system, comprising:

[0008] A metal plate embedded in the upper mold and the lower mold to form a parallel plate capacitor corresponding to the installation position of the metal plate;

[0009] An energizing circuit connected to the metal plate, the energizing circuit being configured to conduct electricity to the metal plate;

[0010] A capacitance information converter connected to the metal plate, the capacitance information converter being configured to measure the capacitance value of the parallel plate capacitor formed by the energized metal plate;

[0011] An information processing module connected to the capacitance information converter;

[0012] The capacitor information converter is used for measuring the capacitor value formed by each parallel plate capacitor, and the information processing module is used for recording the capacitor value change of all parallel plate capacitors and generating a curve.

[0013] As a preferred scheme of the present application, all the metal plates in the upper mold and the lower mold are respectively in the same plane, and the distance between each two corresponding metal plates on the upper mold and the lower mold is the same.

[0014] When the upper mold and the lower mold are closed, the installation position of each metal plate constitutes a parallel plate capacitor.

[0015] As a preferred scheme of the present application, the upper mold and the lower mold are internally provided with slots for installing the metal plates, and when the upper mold and the lower mold are made of metal, an insulating plate is arranged between the metal plate and the upper mold, and an insulating plate is also arranged between the metal plate and the lower mold.

[0016] A plurality of rows of metal plates are sequentially arranged on the plane formed by the slots in the upper mold and the lower mold, and each metal plate is sequentially marked and distinguished according to the order.

[0017] As a preferred scheme of the present application, the upper mold and the lower mold are internally provided with slots for installing the metal plates.

[0018] The distance between all the metal plates in the upper mold and the lower mold is the same, and the side surface area of all the metal plates is the same, and each two position-matched corresponding metal plates in the upper mold and the lower mold constitute a parallel plate capacitor.

[0019] As a preferred scheme of the present application, the information processing module is internally provided with a timer, and when the capacitor information converter measures the change of the capacitor value of the first parallel plate capacitor, the timer is started to begin timing.

[0020] A capacitor value change curve is generated based on the detection time and the capacitor measurement value corresponding to the change of the capacitor value of each parallel plate capacitor, the abscissa of the capacitor value change curve is the timing time, and the ordinate of the capacitor value change curve is the capacitor value detected by the capacitor information converter.

[0021] In order to solve the above technical problems, the present application further provides an implementation method of a capacitor type mold flow sensor system embedded in a mold, comprising the following steps:

[0022] The metal plates are installed in the upper mold and the lower mold.

[0023] The metal plates on the two molds are powered on, or all the metal plates and one of the molds are powered on, to form parallel plate capacitors corresponding to the installation positions of the metal plates, and initial capacitance values of each parallel plate capacitor without material medium are obtained;

[0024] The material medium is poured into the mold cavity, and the capacitance detection values of each parallel plate capacitor are obtained in real time, and the capacitance value change curves of each parallel plate capacitor are generated based on the capacitance detection values and the capacitance change time of each parallel plate capacitor.

[0025] The flow direction of the material medium in the mold cavity and the position of the material medium in the mold cavity are determined based on the capacitance value change curves of all the parallel plate capacitors.

[0026] As a preferred embodiment of the present application, the implementation method for generating the capacitance value change curve of each parallel plate capacitor is:

[0027] The capacitance value C of the parallel plate capacitor formed by each marked metal plate is detected in real time, and the starting time point t1 when the capacitance value starts to change and the ending time point t2 when the capacitance value converges stably are determined.

[0028] The capacitance value C detected in real time is data-fitted with the time point t corresponding to each detection capacitance value to form the capacitance value change curve of each parallel plate capacitor.

[0029] The flow direction of the material medium in the mold cavity and the position of the material medium in the mold cavity are determined based on the capacitance value change curves of all the parallel plate capacitors.

[0030] As a preferred embodiment of the present application, the implementation method for determining the capacitance change direction between the upper mold and the lower mold based on the capacitance value change curves of all the parallel plate capacitors is:

[0031] The capacitance value change curves of all the parallel plate capacitors are integrated into the same coordinate axis.

[0032] The time point t1 when the capacitance value of each parallel plate capacitor starts to change is determined, and the flow direction of the material medium in the mold cavity and the position of the material medium in the mold cavity are determined based on the time points t1 when the capacitance values of different parallel plate capacitors start to change.

[0033] As a preferred embodiment of the present application, the specific implementation method for determining the flow direction of the material medium in the mold cavity is:

[0034] Based on the distribution position of each metal electrode plate on a single mold, a virtual image of electrode plate distribution is constructed, and a virtual two-dimensional coordinate axis of the virtual image of electrode plate distribution is constructed to determine the two-dimensional coordinate value of each metal electrode plate;

[0035] Determine the detection time point corresponding to the change in capacitance value of each parallel plate capacitor formed by the metal plates, and form a two-dimensional array for dielectric flow analysis that integrates the detection time point of capacitance change and the two-dimensional coordinate value of each metal plate with capacitance change.

[0036] According to the detection time points in ascending order, the distribution positions of the metal plates represented by the two-dimensional coordinate values ​​are connected sequentially to form the flow direction of the material medium in the mold cavity.

[0037] As a preferred embodiment of the present invention, the convergence capacitance value of each parallel plate capacitor is determined based on the capacitance value change curve of each parallel plate capacitor, and the dielectric constant corresponding to the final convergence of the capacitance of each parallel plate capacitor is calculated.

[0038] Determine the standard dielectric constant of each of the parallel plate capacitors when the material dielectric is fully filled;

[0039] Calculate the difference between the dielectric constant of each of the parallel plate capacitors and the standard dielectric constant to determine whether there are any parallel plate capacitors that are outside the error range;

[0040] The formula for calculating the dielectric constant of each parallel plate capacitor is as follows:

[0041] ε=Cd / S;

[0042] Where C is the detected capacitance value of the parallel plate capacitor;

[0043] d represents the distance between the metal plates at the two positions on the upper and lower molds, respectively.

[0044] S is the lateral area of ​​the metal electrode plate.

[0045] Compared with the prior art, the present invention has the following advantages:

[0046] The parallel plate capacitor is creatively used as a sensor system for measuring the flowing direction of material medium (such as resin), has small loss, long service time, when the material medium flows into the area of a certain parallel plate capacitor, the filling medium in the parallel plate capacitor changes, thus the dielectric constant also changes, causing the capacitance of the whole parallel plate capacitor to change, thus the installation position of the corresponding metal plate of the parallel plate capacitor based on the capacitance change, and the starting time point of the parallel plate capacitor successively generating the capacitance change can determine the flowing of the material medium.

[0047] The present application can not only determine the flowing direction of the material medium through all the position change curves of the capacitance values of the parallel plate capacitors, but also determine whether the inverse mold of the position of each parallel plate capacitor is qualified based on the capacitance value change, so as to realize the quality inspection work. BRIEF DESCRIPTION OF DRAWINGS

[0048] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are only exemplary, and other drawings can be obtained by the provided drawings without creative labor for those skilled in the art.

[0049] Figure 1 The structure schematic diagram of the capacitive mold flow sensor system of the embodiment of the present application;

[0050] Figure 2 The installation structure schematic diagram of the metal plate of the embodiment of the present application;

[0051] Figure 3 The structure block diagram of the information processing module of the embodiment of the present application;

[0052] Figure 4 The capacitance value change curve schematic diagram of the embodiment of the present application;

[0053] The numbers in the figures respectively represent as follows:

[0054] 1-metal plate; 2-power supply circuit; 3-capacitance information converter; 4-information processing module; 5-information processing module;

[0055] 41-timer. DETAILED DESCRIPTION

[0056] With reference to the drawings and the embodiments of the present application, the technical solutions in the embodiments of the present application will be described clearly and completely. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all the other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application.

[0057] As shown in Figures 1 to 3 The present application provides a capacitive mold flow sensor system embedded in a mold, comprising: a metal plate 1, a power supply circuit 2, a capacitive information converter 3 and an information processing module 4.

[0058] The metal plate 1 is embedded in the upper mold and the lower mold to form a parallel plate capacitor corresponding to the installation position of the metal plate 1.

[0059] The power supply circuit 2 is connected with the metal plate 1, and the power supply circuit 2 is used to conduct electricity to the metal plate 1.

[0060] The capacitive information converter 3 is connected with the metal plate 1, and the capacitive information converter 3 is used to measure the capacitance value of the parallel plate capacitor formed by the metal plate 1 after being powered on.

[0061] The information processing module 4 is connected with the capacitive information converter 3.

[0062] The capacitive information converter 3 is used to measure the capacitance value formed by each parallel plate capacitor, and the information processing module 4 is used to generate the capacitance value change curve of all the parallel plate capacitors after pouring the material medium into the mold cavity.

[0063] It should be further supplemented that the metal plate 1 does not need to be arranged in all upper molds and lower molds in this embodiment, for example, when one of the molds is made of metal and the opposite surface of the mold is a two-dimensional planar structure, only the metal plate 1 needs to be installed in the other mold, and the metal plate 1 forms a parallel plate capacitor with the surface of the metal mold.

[0064] Otherwise, the metal plate 1 needs to be arranged in the upper mold and the lower mold, and the metal plates 1 with the same installation position in the two molds form a parallel plate capacitor.

[0065] In the embodiment, parallel-plate capacitors are formed between the metal electrode plates 1 and between the metal electrode plates 1 and the mold of metal material. The embodiment creatively uses the parallel-plate capacitors as a sensor system for measuring the flowing direction of the material medium (such as resin). When the material medium flows into the area of a certain parallel-plate capacitor, the filling medium in the parallel-plate capacitor changes, and thus the dielectric constant also changes, resulting in a change in the capacitance of the entire parallel-plate capacitor. Therefore, based on the parallel-plate capacitor corresponding to the metal electrode plate 1 installed at the position where the capacitance changes, and the starting time point of the parallel-plate capacitor where the capacitance changes in turn, the flowing of the material medium can be determined, and the flowing of the material medium is determined in units of area.

[0066] Further, the standard capacitance value of each parallel-plate capacitor at the standard mold thickness and the real-time capacitance value of the material medium flowing in can be calculated to determine whether the capacitance values of all parallel-plate capacitors after the material medium is poured are within a reasonable error range of the corresponding standard capacitance values. When the reasonable error range is exceeded, it means that the volume of the material medium at the position of the mold cavity corresponding to the parallel-plate capacitor is different from the standard volume, thereby achieving quality inspection of the product.

[0067] According to the above, in the embodiment, when the upper mold and the lower mold are of non-metal material, or when the opposite surfaces of the upper mold and the lower mold of metal material do not have a two-dimensional plane, grooves need to be provided in the upper mold and the lower mold, and the metal electrode plates 1 are arranged in the grooves. The metal electrode plates 1 on the same mold are in the same plane, that is, all the metal electrode plates 1 in the upper mold and the lower mold are respectively in the same plane, and the distance between every two corresponding metal electrode plates 1 on the upper mold and the lower mold is the same.

[0068] When the upper mold or the lower mold has a two-dimensional plane and the mold with the two-dimensional plane is of metal material, in order to reduce the number of metal electrode plates 1 and the secondary grooving work on the mold, the mold can be used as a parallel plate, and the metal electrode plates 1 are arranged in the other mold. Since the metal electrode plates 1 are in the same plane, the distance between the metal electrode plates 1 and the side surface of the other mold is the same.

[0069] That is, when the surface of the upper mold or the lower mold of metal material is a plane, only grooves for installing the metal electrode plates 1 are provided in the other lower mold or upper mold.

[0070] The distance between all the metal electrode plates 1 and the plane of the upper mold or the lower mold is the same, and each metal electrode plate 1 and the metal region of the same area on the other mold constitute a parallel-plate capacitor.

[0071] Therefore, each metal plate 1 can form a parallel plate capacitor with the two-dimensional plane of another mold, and the number of the parallel plate capacitors is determined by the number of the metal plates 1.

[0072] The upper mold and the lower mold are internally provided with grooves for mounting the metal plates 1, and a plurality of rows of the metal plates 1 are sequentially arranged on the planes formed by the grooves in the upper mold and the lower mold, and each metal plate 1 is sequentially marked and distinguished.

[0073] When the upper mold and the lower mold are made of metal, the metal plate 1 is provided with an insulating plate 5 between the metal plate 1 and the upper mold, and the metal plate 1 is also provided with an insulating plate 5 between the metal plate 1 and the lower mold.

[0074] Further, the implementation principle of measuring the capacitance by the metal plate to build the parallel plate capacitor is as follows: according to the LC resonance circuit principle, the oscillation frequency f can be calculated by the following formula:

[0075]

[0076] Wherein L and C are the original inductance and capacitance values in the measurement circuit before the inverse mode is poured, and ΔC is the change value of the capacitance in the measurement process. The change of the capacitance value is converted into the change of the frequency by the LC resonance circuit according to the principle. And the frequency is converted into a digital output, and the read digital quantity is converted back by the program according to the formula, so that the capacitance value can be obtained.

[0077] In production, most of the molds used are made of metal, and the copper plate cannot be directly embedded in the metal mold, because the whole mold will be electrified after being electrified, so the insulating material must be used to separate the plate and the metal mold, the insulating plate 5 is resistant to high temperature and rigid, and is suitable for insulation and fixation. The upper mold or the lower mold on one side is not metal, and does not need to be insulated.

[0078] The capacitor sensor plate embedded in the mold of the present application does not need to be replaced one by one, consumes slowly, and does not affect the appearance and performance of the product. The capacitor sensor has low cost and high precision, the whole system has low cost, is very suitable for industrial production, and the mold flow monitoring system can change the size, shape, number and the like of the capacitor sensor plate according to the process and product requirements, has wide application range and high flexibility.

[0079] In the embodiment, the metal plates 1 constituting the parallel plate capacitors are sequentially numbered, so that the information processing module 4 can receive the capacitance change of each parallel plate capacitor, further determine the number of the metal plate 1 corresponding to the parallel plate capacitor and the position of the metal plate 1 on the mold, and further determine the flowing direction of the material medium by combining the time when the metal plate 1 appears the capacitance change.

[0080] The information processing module 4 is provided with a timer 41, and the information processing module 4 starts the timer 41 to start timing when the capacitance information converter 3 measures that the capacitance value of the first parallel-plate capacitor changes.

[0081] A capacitance value change curve is generated based on the detection time and the capacitance measurement value corresponding to the change of the capacitance value of each parallel-plate capacitor, the abscissa of the capacitance value change curve is the timing time, and the ordinate of the capacitance value change curve is the capacitance value detected by the capacitance information converter 3.

[0082] Suppose that the cavity inlet of the mold cavity formed by the upper mold and the lower mold is at the upper end, after the material medium is poured into the cavity inlet, the material medium will move downward under the influence of gravity, in order to specifically detect the moving position of the material medium (such as resin), the implementation manner of the embodiment is as follows:

[0083] Before pouring the material medium, the two side plates of each parallel-plate capacitor are electrified, and the initial capacitance value of the parallel-plate capacitor formed by each position of the plate can be obtained.

[0084] After the material medium is poured, the capacitance of different parallel-plate capacitors starts to change because the material medium moves to the positions of different parallel-plate capacitors in turn, the time points at which the capacitance changes of different parallel-plate capacitors are detected, and based on the time sequence of the detected capacitance changes, the flowing direction of the material medium can be determined.

[0085] After the injection molding is completed, the capacitance of each parallel-plate capacitor gradually starts to converge, and the converged capacitance value is compared with the standard capacitance value of the parallel-plate capacitor at the position, when the converged capacitance value is greater than the standard capacitance value, it means that the material medium filling amount at the position is not in the standard range, similarly, when the converged capacitance value is less than the standard capacitance value, it means that the material medium filling amount at the position is not in the standard range, and the thickness of the product produced this time is uneven, so that the quality inspection work of the mold produced product can be further realized.

[0086] Only when the converged capacitance value is within a reasonable error range of the standard capacitance value, it means that the material medium filling amount at the position is in the standard range, so the mold flow sensor system in the embodiment not only detects the flowing direction of the material medium in the mold cavity, but also combines the principle of capacitance detection and the parameters affecting the capacitance value to perform quality inspection work on the products produced by the mold.

[0087] The implementation method of the capacitance type mold flow sensor system embedded in the mold includes the following steps:

[0088] The metal plate is installed in the upper mold and the lower mold;

[0089] The two metal plates on the two molds, or all the metal plates and one of the molds, are powered to form parallel-plate capacitors corresponding to the installation positions of the metal plates, and initial capacitance values of each parallel-plate capacitor without being powered into a material medium are obtained;

[0090] The material medium is poured into the mold cavity, real-time capacitance detection values of each parallel-plate capacitor are obtained, and capacitance value change curves of each parallel-plate capacitor are generated based on the capacitance detection values and capacitance change times of each parallel-plate capacitor;

[0091] The capacitance change direction between the upper mold and the lower mold is determined based on the capacitance value change curves of all the parallel-plate capacitors, so as to determine the flow direction of the material medium in the mold cavity and the position of the material medium in the mold cavity.

[0092] In the embodiment, metal plates are generally arranged in the upper mold and the lower mold, the metal plates in each mold are in the same plane, the spacing and distribution area of the metal plates in the two molds are the same, and the only parameter affecting the capacitance value between the two metal plates in the same position is the dielectric constant, i.e., the flow direction of the filled material medium (such as resin).

[0093] When one of the molds is a metal medium and the opposite surface of the mold to the other mold is a two-dimensional plane, the mold can be used as one side plate of a parallel-plate capacitor, and metal plates are arranged in the other mold by slotting, so that each metal plate and the surface of the opposite mold form a parallel-plate capacitor.

[0094] In order to further illustrate how to detect the flow direction of the material medium, it is assumed that four metal plates are arranged in the two molds respectively, and each two metal plates are oppositely distributed, so that the two metal plates on the two molds can form a parallel-plate capacitor.

[0095] The implementation method for generating the capacitance value change curve of each parallel-plate capacitor is as follows:

[0096] The capacitance value C of the parallel-plate capacitor formed by each marked metal plate is detected in real time, and the starting time point t1 at which the capacitance value starts to change and the ending time point t2 at which the capacitance value stably converges are determined;

[0097] The real-time detected capacitance value C and the time point t corresponding to each detection capacitance value are data-fitted to form the capacitance value change curve of each parallel-plate capacitor;

[0098] The starting time points t1 of the capacitance value change curves of all the parallel-plate capacitors are combined to determine the capacitance change direction between the upper mold and the lower mold.

[0099] Specifically, assuming that the material medium is poured from top into the mold cavity, the material medium will flow from top to bottom, so the capacitance between the two parallel plate capacitors in the upper row changes almost simultaneously at time t1, while the capacitance between the two parallel plate capacitors in the lower row changes simultaneously at time t2. After integrating the four capacitance value change curves into the same coordinate axis, the specific formation is as shown in the curve diagram. Figure 4

[0100] Since the capacitance change start time t2 of the two parallel plate capacitors in the lower row is greater than the capacitance change start time t1 of the two parallel plate capacitors in the upper row, it can be judged that the flow direction of the material medium is from top to bottom.

[0101] That is, the implementation method for determining the capacitance change direction between the upper mold and the lower mold based on the capacitance value change curves of all parallel plate capacitors is:

[0102] Integrating the capacitance value change curves of all parallel plate capacitors into the same coordinate axis;

[0103] Determining the time point t1 corresponding to the start of the capacitance value change of each parallel plate capacitor, and determining the flow direction of the material medium in the mold cavity and the position of the material medium in the mold cavity based on the time point t1 corresponding to the start of the capacitance value change of different parallel plate capacitors.

[0104] In order to further determine the flow direction of the material medium in the mold cavity, the distribution position of each metal electrode plate needs to be determined, and the specific implementation method is:

[0105] Based on the distribution position of each metal electrode plate on a single mold, a virtual image of the electrode plate distribution is constructed, and a virtual two-dimensional coordinate axis of the virtual image of the electrode plate distribution is constructed to determine the two-dimensional coordinate value of each metal electrode plate.

[0106] Determining the detection time point corresponding to the change of the capacitance value of the parallel plate capacitor formed by each metal electrode plate, and forming a medium flow direction analysis two-dimensional array integrating the detection time point and the two-dimensional coordinate value of each metal electrode plate with capacitance change.

[0107] According to the order of the detection time point from small to large, the distribution positions of the metal electrode plates represented by the two-dimensional coordinate values are connected in turn to form the flow direction of the material medium in the mold cavity.

[0108] Based on the capacitance value change curve of each parallel plate capacitor, the convergence capacitance value of each parallel plate capacitor is determined, and the dielectric constant corresponding to the final convergence of the capacitance of each parallel plate capacitor is calculated.

[0109] The standard dielectric constant corresponding to the standard fullness of the material medium of each parallel plate capacitor is determined respectively.​

[0110] a difference between the dielectric constant of each parallel-plate capacitor and a standard dielectric constant is calculated to determine whether the parallel-plate capacitor exceeds an error range;

[0111] wherein a calculation formula of the dielectric constant corresponding to each parallel-plate capacitor is:

[0112] ε = Cd / S;

[0113] wherein C is a detection capacitance value of the parallel-plate capacitor;

[0114] d is a distance between the metal plates corresponding to two positions respectively on the upper mold and the lower mold;

[0115] S is a side area of the metal plate.

[0116] Suppose that a standard dielectric constant corresponding to a standard full material medium at a position of each parallel-plate capacitor is ε1, and after the material medium is poured, when the capacitance of each parallel-plate capacitor finally converges, the dielectric constant of the parallel-plate capacitor at the position is ε2. The difference between the dielectric constant ε2 corresponding to the final convergence of the capacitance of each parallel-plate capacitor and the standard dielectric constant ε1 corresponding to the standard full material medium at the position is calculated. When the difference is within a reasonable range, it means that the thickness of the material medium at the position is within a reasonable thickness error range. When the difference exceeds the reasonable range, it means that the thickness of the material medium at the position exceeds the reasonable thickness error range.

[0117] Therefore, the embodiment can not only determine the flow direction of the material medium through the capacitance value change curve of all the parallel-plate capacitors, but also determine whether the inverted mold at the position of each parallel-plate capacitor is qualified based on the capacitance value change, so as to realize quality inspection work.

[0118] The above examples are only exemplary embodiments of the present application and are not used to limit the present application. The protection scope of the present application is defined by the claims. Those skilled in the art can make various modifications or equivalent replacements to the present application within the spirit and protection scope of the present application, and such modifications or equivalent replacements are also regarded as falling within the protection scope of the present application.

Claims

1. An implementation method of an embedded mold capacitive mold flow sensor system, characterized by, The method comprises the following steps: installing metal electrodes in the upper and lower molds; energizing all the metal electrodes on the two molds or all the metal electrodes and one of the molds to form parallel-plate capacitors corresponding to the installation positions of the metal electrodes, and obtaining initial capacitance values of each parallel-plate capacitor without being filled with a material medium; pouring the material medium into the mold cavity, obtaining capacitance detection values of each parallel-plate capacitor in real time, and generating a capacitance value change curve of each parallel-plate capacitor based on the capacitance detection value and the capacitance change time of each parallel-plate capacitor; determining the capacitance change direction between the upper and lower molds based on the capacitance value change curves of all the parallel-plate capacitors to determine the flow direction of the material medium in the mold cavity and the position of the material medium in the mold cavity; the implementation method for determining the capacitance change direction between the upper and lower molds based on the capacitance value change curves of all the parallel-plate capacitors is: integrating the capacitance value change curves of all the parallel-plate capacitors into the same coordinate axis; determining the time point t1 corresponding to the start of the capacitance value change of each parallel-plate capacitor, and determining the flow direction of the material medium in the mold cavity and the position of the material medium in the mold cavity based on the time points t1 corresponding to the start of the capacitance value change of different parallel-plate capacitors.

2. The implementation method of the capacitive mold flow sensor system embedded in the mold according to claim 1, wherein the implementation method for generating the capacitance value change curve of each parallel-plate capacitor is: detecting the capacitance value C of the parallel-plate capacitor formed by each marked metal electrode in real time, and determining the start time point t1 at which the capacitance value starts to change and the end time point t2 corresponding to the stable convergence of the capacitance value; performing data fitting on the capacitance value C detected in real time and the time point t corresponding to each detection capacitance value to form the capacitance value change curve of each parallel-plate capacitor; combining the capacitance value change curves of all the parallel-plate capacitors to determine the capacitance change direction between the upper and lower molds.

3. The implementation method of the capacitive mold flow sensor system embedded in the mold according to claim 1, wherein the specific implementation method for determining the flow direction of the material medium in the mold cavity is: constructing an electrode distribution virtual image based on the distribution positions of each metal electrode on a single mold, constructing a virtual two-dimensional coordinate axis of the electrode distribution virtual image, and determining the two-dimensional coordinate value of each metal electrode; determining the detection time point corresponding to the change of the capacitance value of the parallel-plate capacitor formed by each metal electrode, and forming a medium flow direction analysis two-dimensional array integrating the detection time point and the two-dimensional coordinate value of each metal electrode with capacitance change; connecting the distribution positions of the metal electrodes represented by the two-dimensional coordinate values in the order from small to large of the detection time points to form the flow direction of the material medium in the mold cavity. 4.The implementation method of the embedded mold capacitive mold flow sensor system according to claim 2, wherein, based on the capacitance variation curve of each parallel-plate capacitor, the convergent capacitance value of each parallel-plate capacitor is determined, and the dielectric constant corresponding to the final convergence of the capacitance of each parallel-plate capacitor is calculated. The standard dielectric constant of each parallel-plate capacitor when the material medium is fully charged is determined respectively. The difference between the dielectric constant and the standard dielectric constant of each parallel-plate capacitor is calculated to determine whether there is a parallel-plate capacitor that exceeds the error range. The calculation formula of the dielectric constant corresponding to each parallel-plate capacitor is as follows: ε=Cd / S; Wherein, C is the detected capacitance value of the parallel-plate capacitor; d is the distance between the two metal plates corresponding to the positions of the upper mold and the lower mold respectively; S is the side area of the metal plate. The capacitive mold flow sensor system comprises:

5. The method of claim 1, wherein, a metal plate (1) embedded in the upper mold and the lower mold to form a parallel-plate capacitor corresponding to the installation position of the metal plate (1); a power supply circuit (2) connected to the metal plate (1), the power supply circuit (2) is used to conduct electricity to the metal plate (1); a capacitance information converter (3) connected to the metal plate (1), the capacitance information converter (3) is used to measure the capacitance value of the parallel-plate capacitor formed by the metal plate (1) after being powered on; an information processing module (4) connected to the capacitance information converter (3); The capacitance information converter (3) is used to measure the capacitance value of each parallel-plate capacitor, and the information processing module (4) is used to record the capacitance value variation of all parallel-plate capacitors and generate a curve. 6.The implementation method of the embedded mold capacitive mold flow sensor system according to claim 5, wherein, all metal plates (1) in the upper mold and the lower mold are respectively in the same plane, and the distance between every two corresponding metal plates (1) on the upper mold and the lower mold is the same; when the upper mold and the lower mold are closed, the installation position of each metal plate (1) forms a parallel-plate capacitor. 7.The implementation method of the embedded mold capacitive mold flow sensor system according to claim 5, wherein, the upper mold and the lower mold are provided with slots for installing the metal plates (1), and when the upper mold and the lower mold are made of metal, the metal plate (1) is provided with an insulating plate (5) between the metal plate (1) and the upper mold, and the metal plate (1) is also provided with an insulating plate (5) between the metal plate (1) and the lower mold; a plurality of rows of metal plates (1) are sequentially arranged on the plane formed by the slots in the upper mold and the lower mold, and each metal plate (1) is sequentially marked and distinguished according to the order. 8.The implementation method of the embedded mold capacitive mold flow sensor system according to claim 7, wherein, the upper mold and the lower mold are provided with slots for installing the metal plates (1). ​ The distance between all metal plates (1) in the upper mold and the lower mold is the same, and the side surface area of all metal plates (1) is the same, and every two position-matched corresponding metal plates (1) in the upper mold and the lower mold constitute a parallel plate capacitor.

9. The implementation method of the embedded mold capacitive mold flow sensor system according to claim 5, characterized in that, The information processing module (4) is provided with a timer (41), and the information processing module (4) starts the timer (41) to start timing when the capacitive information converter (3) measures the change of the capacitance value of the first parallel plate capacitor; The capacitance value change curve is generated based on the detection time and the capacitance measurement value corresponding to the change of the capacitance value of each parallel plate capacitor, the abscissa of the capacitance value change curve is the timing time, and the ordinate of the capacitance value change curve is the capacitance value detected by the capacitive information converter (3).

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