Infiltration die head automatic control system capable of improving dispersion and distribution uniformity of long glass fibers

Abstract

The invention relates to the technical field of plastic melting devices, in particular to an automatic infiltration die head control system capable of improving dispersion and distribution uniformity of long glass fibers, which comprises a die head main body, a heater and a die head unit of a rotating roller, wherein the surface of the die head main body is provided with a long glass fiber bundle input port, a melt input port and a long glass fiber reinforced plastic output port; a first channel and a second channel are arranged in the die head main body, a converging cavity is formed in one end, close to the long glass fiber bundle input port, of the first channel, and an infiltration cavity is formed between the first channel and the long glass fiber reinforced plastic output port; comprising a cold water tank; comprising a traction machine; an acquisition unit; and the control unit is used for increasing the rotating speed of the rotating roller under the condition of judging that the infiltration of the long glass fiber tow does not meet the preset standard, or secondarily judging whether the infiltration of the long glass fiber tow meets the preset standard or not according to the arrangement evaluation value, so that the quality of the long glass fiber reinforced plastic is improved.

Description

Technical Field

[0001] The invention relates to the technical field of plastic melting devices, in particular to an automatic control system for a wetting die head capable of improving the dispersion and distribution uniformity of long glass fibers. Background Art

[0002] Long glass fiber reinforced plastic is a high-performance composite material that uses long glass fibers as reinforcing materials and is compounded with matrix materials through a specific process. The addition of long glass fibers significantly improves the mechanical properties of the material, giving it higher strength and modulus.

[0003] The dispersion and distribution uniformity of long glass fibers have a significant impact on the performance of long glass fiber reinforced plastics. When long glass fibers are well dispersed and evenly distributed in the plastic matrix, they can effectively improve the mechanical properties of the material, such as tensile strength, bending strength and impact strength; if the long glass fibers are unevenly dispersed, it will lead to problems such as stress concentration and crack propagation in the material.

[0004] The impregnation die is a specially designed die whose main function is to ensure that the long glass fiber can be evenly and fully impregnated in the molten material during the composite material manufacturing process.

[0005] China Patent Publication (Announcement) No.: CN105109008B, discloses a twin-screw extruder long glass fiber reinforced die head, including a die body, a runner and a cooling device, one side of the die body is provided with an insert, the runner includes a first runner, a second runner, and a third runner, a feed port is provided on the surface of the insert, one end of the feed port is connected to the first runner, one end of the first runner is connected to the third runner through the second runner, one end of the third runner is connected to the discharge pipe, a runner is provided with a flow comb inside, and the cooling device includes an upper cooling pipe, a lower cooling pipe, an upper suction pipe, a lower suction pipe, an upper air intake pipe, a lower air intake pipe, an air intake pump and a refrigerator. The twin-screw extruder long glass fiber reinforced die head can achieve fine extrusion of molten plastic by setting the first runner, the second runner and the third runner of different shapes, and ensure that the extruded plastic wire has high roundness accuracy. It can be seen that although the long glass fiber reinforced die of the twin-screw extruder in the prior art realizes the fine extrusion of the molten plastic by setting the branch channels of different shapes, thus ensuring the high roundness accuracy of the extruded plastic wire, the dispersion and distribution uniformity of the long glass fiber in the die are not considered, resulting in poor wetting effect of the long glass fiber in the plastic matrix, thus leading to poor quality of the long glass fiber reinforced plastic. Summary of the invention

[0006] To this end, the present invention provides an automatic control system for a wetting die head that can improve the uniformity of dispersion and distribution of long glass fibers, so as to overcome the problem in the prior art that the uniformity of dispersion and distribution of long glass fibers in the die head is not taken into consideration, resulting in poor wetting effect of long glass fibers in the plastic matrix, thereby leading to poor quality of long glass fiber reinforced plastics.

[0007] To achieve the above object, the present invention provides an automatic control system for a wetting die head capable of improving the uniformity of dispersion and distribution of long glass fibers, characterized in that it comprises:

[0008] a die unit including a die body, a heater and a rotating roller;

[0009] The surface of the die body is provided with a long glass fiber bundle input port, a molten material input port and a long glass fiber reinforced plastic output port, the die body is provided with a first channel and a second channel, the first channel is connected with the long glass fiber bundle input port and the long glass fiber reinforced plastic output port respectively, one end of the second channel is connected with the molten material input port, the other end of the second channel is connected with the first channel through a convergence cavity, an impregnation cavity is provided between the first channel and the long glass fiber reinforced plastic output port; the heater is provided on the side wall of the second channel; the rotating roller is provided in the impregnation cavity, and the surface of the rotating roller is provided with equidistant protrusions;

[0010] A cooling unit, which is arranged at the output end of the die unit and includes a cold water tank;

[0011] A traction unit, which is arranged at the output end of the cooling unit and includes a traction machine;

[0012] A collection unit, comprising an image collection module for collecting the hairiness length on the surface of the long glass fiber bundle and the crack length on the end surface of the long glass fiber reinforced plastic, and a mechanical property collection module for collecting the tensile modulus and tensile strength of the long glass fiber reinforced plastic;

[0013] A control unit is respectively connected to the die unit, the cooling unit, the traction unit and the collection unit, and is used to increase the rotation speed of the rotating roller under the condition that the wetting of the long glass fiber bundle does not meet the preset standard according to the wetting uniformity characteristic value, or to determine whether the wetting of the long glass fiber bundle meets the preset standard for the second time according to the arrangement evaluation value.

[0014] Furthermore, the control unit determines whether the wetting of the long glass fiber bundle meets a preset standard according to the wetting uniformity characteristic value, wherein:

[0015] If the wetting uniformity characteristic value is less than the first preset wetting uniformity threshold value, the control unit determines that the wetting of the long glass fiber bundle does not meet the preset standard, and increases the rotation speed of the rotating roller according to the difference between the first preset wetting uniformity threshold value and the wetting uniformity characteristic value;

[0016] If the infiltration uniformity characteristic value is greater than or equal to the first preset infiltration uniformity threshold value and less than the second preset infiltration uniformity threshold value, the control unit determines that the infiltration of the long glass fiber bundle does not meet the preset standard, and determines whether the infiltration of the long glass fiber bundle meets the preset standard for the second time according to the arrangement evaluation value;

[0017] If the wetting uniformity characteristic value is greater than or equal to the second preset wetting uniformity threshold, the control unit determines that the wetting of the long glass fiber bundle meets the preset standard.

[0018] Furthermore, the wettability uniformity characteristic value is an average value of the hairiness length on the surface of the long glass fiber bundle.

[0019] Furthermore, the control unit is provided with several speed increasing modes for increasing the speed of the rotating roller, wherein:

[0020] If the wetting difference is less than the first preset wetting difference, the control unit increases the rotation speed of the rotating roller using a first preset adjustment coefficient;

[0021] If the wetting difference is greater than or equal to the first preset wetting difference and less than the second preset wetting difference, the control unit increases the rotation speed of the rotating roller using a second preset adjustment coefficient;

[0022] If the wetting difference is greater than or equal to the second preset wetting difference, the control unit increases the rotation speed of the rotating roller using a third preset adjustment coefficient;

[0023] The wetting difference is the difference between the first preset wetting uniformity threshold and the wetting uniformity characteristic value.

[0024] Furthermore, the control unit determines whether the infiltration of the long glass fiber bundle meets the preset standard based on the arrangement evaluation value of the long glass fiber bundle, wherein:

[0025] If the arrangement evaluation value is less than the preset arrangement threshold, the control unit determines that the infiltration of the long glass fiber bundle does not meet the preset standard, and determines the adjustment method under the condition that the infiltration of the long glass fiber bundle does not meet the preset standard according to the tensile characteristic value;

[0026] If the arrangement evaluation value is greater than or equal to the preset arrangement threshold, the control unit determines that the wetting of the long glass fiber bundle meets the preset standard.

[0027] Furthermore, the arrangement evaluation value is obtained by the distance between each long glass fiber filament in the long glass fiber reinforced plastic.

[0028] Furthermore, the control unit determines an adjustment method under the condition that the impregnation of the long glass fiber bundle does not meet the preset standard according to the tensile characteristic value of the long glass fiber reinforced plastic, wherein:

[0029] If the stretch characteristic value is less than the preset stretch threshold value, the control unit increases the injection pressure of the melt according to the difference between the preset stretch threshold value and the stretch characteristic value;

[0030] If the stretching characteristic value is greater than or equal to the preset stretching threshold, the control unit reduces the traction rate of the traction machine according to the difference between the stretching characteristic value and the preset stretching threshold;

[0031] The tensile characteristic value is determined by the tensile modulus of the long glass fiber reinforced plastic and the tensile strength of the long glass fiber reinforced plastic. Further, the increase of the injection pressure is positively correlated with the tensile difference, wherein the tensile difference is the difference between the preset tensile threshold and the tensile characteristic value.

[0032] Further, under the first preset condition, the control unit determines the correction method of the injection pressure according to the crack characteristic difference of the long glass fiber reinforced plastic, wherein:

[0033] If the crack characteristic difference is less than a first preset crack characteristic difference, the control unit uses a first pressure correction coefficient to correct the injection pressure;

[0034] If the crack characteristic difference is greater than or equal to the first preset crack characteristic difference and less than the second preset crack characteristic difference, the control unit uses a second pressure correction coefficient to correct the injection pressure;

[0035] If the crack characteristic difference is greater than or equal to the second preset crack characteristic difference, the control unit corrects the injection pressure using a third pressure correction coefficient;

[0036] The first preset condition is that after the injection pressure of the melt is increased, the crack characteristic value of the long glass fiber reinforced plastic exceeds the preset crack characteristic value; the crack characteristic difference is the difference between the crack characteristic value and the preset crack characteristic value.

[0037] Furthermore, the crack characteristic value is determined by the total length of the cracks on the end surface of the long glass fiber reinforced plastic.

[0038] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention optimizes the production of long glass fiber reinforced plastics through the combined design of the die unit, the cooling unit, the traction unit, the collection unit and the control unit; the dispersion and distribution uniformity of the long glass fiber impregnation is evaluated through the impregnation uniformity characteristic value and the arrangement evaluation value, and the corresponding measures are discovered and taken in time, thereby improving the quality of the long glass fiber reinforced plastics.

[0039] Furthermore, the present invention determines whether the wetting of the long glass fiber bundle meets the preset standard according to the wetting uniformity characteristic value through the control unit, accurately controls the wetting process of the die head, ensures the wetting uniformity of the long glass fiber bundle, and thus improves production efficiency.

[0040] Furthermore, the present invention is provided with a wetting uniformity characteristic value determined by the average curvature of the long glass fiber bundle and the hairiness value on the surface of the long glass fiber bundle. The average curvature of the long glass fiber bundle characterizes its overall bending shape, the hairiness value is used to measure the roughness of the fiber surface for real-time evaluation of the wetting effect, and the wetting uniformity characteristic value is the average value of the hairiness length, which can comprehensively reflect the quality of the wetting effect, thereby more accurately judging whether the wetting of the long glass fiber bundle meets the standard.

[0041] Furthermore, the present invention determines whether the wetting of the long glass fiber bundle meets the preset standard by secondarily judging the arrangement evaluation value of the long glass fiber bundle, thereby improving the accuracy of the determination.

[0042] Furthermore, the present invention determines the adjustment method under the condition that the impregnation of the long glass fiber bundle does not meet the preset standard through the tensile characteristic value of the long glass fiber reinforced plastic, optimizes the parameters of the impregnation process, and thus improves the intelligence level of the control system.

[0043] Furthermore, the present invention is provided with a correction method for determining the injection pressure according to the crack characteristic difference of the long glass fiber reinforced plastic. If the injection pressure is too high, excessive stress will be generated inside the material, resulting in cracks. By controlling the injection pressure, the crack generation is reduced, thereby improving product quality.

[0044] Furthermore, the present invention provides that the increase amplitude of the injection pressure is positively correlated with the stretching difference, thereby achieving precise regulation of the increase amplitude of the injection pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 This is a unit connection diagram of an automatic control system for a wetting die head that can improve the uniformity of dispersion and distribution of long glass fibers according to an embodiment of the present invention;

[0046] Figure 2 This is a schematic structural diagram of a die unit capable of improving the dispersion and distribution uniformity of long glass fibers according to an embodiment of the present invention;

[0047] Figure 3 This is a flow chart of determining whether the infiltration of a long glass fiber bundle meets a preset standard according to an infiltration uniformity characteristic value according to an embodiment of the present invention;

[0048] Figure 4 This is a flow chart of an embodiment of the present invention for secondary determination of whether the wetting of a long glass fiber bundle meets a preset standard according to an arrangement evaluation value;

[0049] In the figure: 11, die body; 12, heater; 13, rotating roller; 14, long glass fiber bundle input port; 15, melt input port; 16, long glass fiber reinforced plastic output port; 17, converging chamber; 18, impregnation chamber. DETAILED DESCRIPTION

[0050] In order to make the objects and advantages of the present invention more clearly understood, the present invention is further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0051] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0052] See also Figure 1 , Figure 2 , Figure 3 as well as Figure 4 As shown, they are respectively a unit connection diagram of an automatic control system for a wetting die that can improve the uniformity of dispersion and distribution of long glass fibers according to an embodiment of the present invention; a structural schematic diagram of a die unit that can improve the uniformity of dispersion and distribution of long glass fibers according to an embodiment of the present invention; a flow chart of determining whether the wetting of a long glass fiber bundle meets a preset standard based on a wetting uniformity characteristic value according to an embodiment of the present invention; and a flow chart of determining whether the wetting of a long glass fiber bundle meets a preset standard based on an arrangement evaluation value according to an embodiment of the present invention.

[0053] An embodiment of the present invention provides an automatic control system for a wetting die head capable of improving the dispersion and distribution uniformity of long glass fibers, characterized in that it includes:

[0054] The die unit includes a die body 11, a heater 12 and a rotating roller 13;

[0055] The surface of the die body 11 is provided with a long glass fiber bundle input port 14, a molten material input port 15 and a long glass fiber reinforced plastic output port 16, and the die body 11 is provided with a first channel and a second channel, wherein the first channel is connected to the long glass fiber bundle input port 14 and the long glass fiber reinforced plastic output port 16 respectively, one end of the second channel is connected to the molten material input port 15, and the other end of the second channel is connected to the first channel through a converging cavity 17, and an impregnation cavity 18 is provided between the first channel and the long glass fiber reinforced plastic output port 16; the heater 12 is provided on the side wall of the second channel; the rotating roller 13 is provided in the impregnation cavity 18, and the surface of the rotating roller 13 is provided with equidistant protrusions;

[0056] A cooling unit, which is arranged at the output end of the die unit and includes a cold water tank;

[0057] A traction unit, which is arranged at the output end of the cooling unit and includes a traction machine;

[0058] A collection unit, comprising an image collection module for collecting the hairiness length on the surface of the long glass fiber bundle and the crack length on the end surface of the long glass fiber reinforced plastic, and a mechanical property collection module for collecting the tensile modulus and tensile strength of the long glass fiber reinforced plastic;

[0059] A control unit is respectively connected to the die unit, the cooling unit, the traction unit and the collection unit, and is used to increase the rotation speed of the rotating roller 13 under the condition that the wetting of the long glass fiber bundle does not meet the preset standard according to the wetting uniformity characteristic value, or to determine whether the wetting of the long glass fiber bundle meets the preset standard for the second time according to the arrangement evaluation value.

[0060] In this embodiment, the specific models of the cold water tank and the traction machine are not limited, and they only need to meet the requirements of traction of the long glass fiber bundle and cooling of the long glass fiber bundle after soaking.

[0061] The specific structure of the control unit is not limited, and it can be composed of logic components, including field programmable components, computers or microprocessors in computers.

[0062] Specifically, the control unit determines whether the wetting of the long glass fiber bundle meets the preset standard according to the wetting uniformity characteristic value, wherein:

[0063] If the wetting uniformity characteristic value is less than the first preset wetting uniformity threshold value of 0.36 mm, the control unit determines that the wetting of the long glass fiber bundle does not meet the preset standard, and increases the rotation speed of the rotating roller 13 according to the difference between the first preset wetting uniformity threshold value and the wetting uniformity characteristic value;

[0064] If the infiltration uniformity characteristic value is greater than or equal to the first preset infiltration uniformity threshold value and less than the second preset infiltration uniformity threshold value of 0.67 mm, the control unit determines that the infiltration of the long glass fiber bundle does not meet the preset standard, and determines whether the infiltration of the long glass fiber bundle meets the preset standard according to the arrangement evaluation value for the second time;

[0065] If the wetting uniformity characteristic value is greater than or equal to the second preset wetting uniformity threshold, the control unit determines that the wetting of the long glass fiber bundle meets the preset standard.

[0066] Specifically, the long glass fiber bundle is photographed by a high-resolution camera, and the average value of the hairiness length on the surface of the long glass fiber bundle is obtained by a contour extraction algorithm, and recorded as the wetting uniformity characteristic value.

[0067] It can be understood that the wettability of long glass fiber refers to the interaction ability between long glass fiber and molten material, which affects the performance and quality of long glass fiber reinforced plastics.

[0068] It is understandable that the hairiness on the surface of the long glass fiber bundle is the part of the fiber protruding from the fiber end or break. When the glass fiber bundle is soaked in the molten material, the molten material will penetrate between the fibers and try to cover the fiber surface. If the soaking is uneven, the distribution of the molten material on the fiber surface will be inconsistent, resulting in the hairiness in some areas being fully covered by the molten material, while the hairiness in other areas remains intact or is only partially covered. Therefore, the average value of the length of the hairiness is detected to characterize the uniform soaking effect of the molten material on the long glass fiber.

[0069] Specifically, the control unit is provided with several speed increasing modes for increasing the speed of the rotating roller 13, wherein:

[0070] If the wetting difference is less than the first preset wetting difference of 0.12, the control unit increases the rotation speed of the rotating roller 13 using a first preset adjustment coefficient of 1.04;

[0071] If the wetting difference is greater than or equal to the first preset wetting difference and less than the second preset wetting difference of 0.31, the control unit increases the rotation speed of the rotating roller 13 using the second preset adjustment coefficient of 1.06;

[0072] If the wetting difference is greater than or equal to the second preset wetting difference, the control unit increases the rotation speed of the rotating roller 13 using a third preset adjustment coefficient of 1.08;

[0073] The wetting difference is the difference between the first preset wetting uniformity threshold and the wetting uniformity characteristic value.

[0074] Specifically, the control unit determines whether the wetting of the long glass fiber bundle meets the preset standard based on the arrangement evaluation value of the long glass fiber bundle.

[0075] If the arrangement evaluation value is less than the preset arrangement threshold value of 0.44, the control unit determines that the infiltration of the long glass fiber bundle does not meet the preset standard, and determines the adjustment method under the condition that the infiltration of the long glass fiber bundle does not meet the preset standard according to the tensile characteristic value;

[0076] If the arrangement evaluation value is greater than or equal to the preset arrangement threshold, the control unit determines that the wetting of the long glass fiber bundle meets the preset standard.

[0077] Specifically, the ranking evaluation value is calculated by the following formula:

[0078]

[0079] In the formula, Q represents the ranking evaluation value; n represents the total number of distance values; d i Represents the distance value between the i-th fiber filaments; Represents the average value of all distance values; i=1, 2, 3, ..., n;

[0080] The distance between each long glass fiber in the long glass fiber reinforced plastic is measured by a fiber spacing measuring instrument.

[0081] Specifically, the control unit determines the adjustment method under the condition that the wetting of the long glass fiber bundle does not meet the preset standard according to the tensile characteristic value of the long glass fiber reinforced plastic, wherein:

[0082] If the stretching characteristic value is less than the preset stretching threshold value of 0.68, the control unit increases the injection pressure of the melt according to the difference between the preset stretching threshold value and the stretching characteristic value;

[0083] If the stretching characteristic value is greater than or equal to the preset stretching threshold, the control unit reduces the traction rate of the traction machine according to the difference between the stretching characteristic value and the preset stretching threshold;

[0084] It can be understood that when the tensile characteristic value is less than the preset tensile threshold value, it means that the tensile strength and tensile modulus of the long glass fiber reinforced plastic are unqualified, and the bonding force between the fiber and the melt is small, thereby reducing the tensile properties of the material; to solve this problem, increasing the injection pressure of the melt helps the melt to better penetrate into the fiber bundle and improve the wetting effect;

[0085] When the tensile characteristic value is greater than or equal to the preset tensile threshold, it means that the tensile performance of the long glass fiber reinforced plastic meets the standard under the condition that the impregnation of the long glass fiber bundle does not meet the standard. Even if the tensile performance meets the standard, if the pulling rate of the pulling machine is too high, defects will occur or the product quality will be reduced. Therefore, the control unit will reduce the pulling rate of the pulling machine according to the difference between the tensile characteristic value and the preset tensile threshold. This can reduce the stress of the material during the pulling process, reduce the generation of defects, and maintain the tensile performance of the material.

[0086] The tensile characteristic value is calculated by the following formula:

[0087]

[0088] In the formula, P is the tensile characteristic value; E1 is the tensile modulus of long glass fiber reinforced plastic; E0 is the preset tensile modulus, E0=7000MPa; Provides tensile strength for long glass fiber reinforced plastics; To preset the tensile strength, ; is the weight coefficient of the tensile modulus of long glass fiber reinforced plastics, ; is the weight coefficient of the tensile strength of long glass fiber reinforced plastics, .

[0089] In this embodiment, the tensile modulus of the long glass fiber reinforced plastic is obtained according to standards, such as GB / T1446-2013.

[0090] In this embodiment, the tensile strength of the long glass fiber reinforced plastic is obtained according to standards, such as GB / T1447-2005.

[0091] Specifically, the increase in the injection pressure is positively correlated with the stretching difference, wherein the positive correlation is, for example, a linear positive correlation or a nonlinear positive correlation, and the linear slope of the linear positive correlation is not specifically limited. It can be understood that the larger the stretching difference is, the larger the increase in the injection pressure is; the stretching difference is the difference between a preset stretching threshold and a stretching characteristic value.

[0092] Specifically, under the first preset condition, the control unit determines the correction method of the injection pressure according to the crack characteristic difference of the long glass fiber reinforced plastic, wherein:

[0093] If the crack characteristic difference is less than the first preset crack characteristic difference of 0.25, the control unit uses a first pressure correction coefficient of 0.97 to correct the injection pressure;

[0094] If the crack characteristic difference is greater than or equal to the first preset crack characteristic difference and less than the second preset crack characteristic difference of 0.42, the control unit uses a second pressure correction coefficient of 0.95 to correct the injection pressure;

[0095] If the crack characteristic difference is greater than or equal to the second preset crack characteristic difference, the control unit uses a third pressure correction coefficient of 0.93 to correct the injection pressure;

[0096] The first preset condition is that after increasing the injection pressure of the melt, the crack characteristic value of the long glass fiber reinforced plastic exceeds the preset crack characteristic value; the crack characteristic difference is the difference between the crack characteristic value and the preset crack characteristic value of 0.94.

[0097] It is understandable that excessive injection pressure will cause the molten material to flow too violently in the mold, generating greater shear force and impact force. When the internal stress exceeds the material's bearing limit, cracks will occur on the end face, which will also cause greater residual stress inside the plastic part. The cracks will extend in the direction of stress concentration. As the cracks extend, their length will gradually increase, eventually leading to a serious decrease in the mechanical properties of long glass fiber reinforced plastics.

[0098] Specifically, the crack characteristic value is the ratio between the total crack length of the end surface of the long glass fiber reinforced plastic and the preset total crack length.

[0099] In this embodiment, the crack length of the end surface of the long glass fiber reinforced plastic is measured by scanning electron microscopy, and the total crack length of the end surface of the long glass fiber reinforced plastic is the sum of the crack lengths of several end surfaces of the long glass fiber reinforced plastic.

[0100] In this embodiment, the preset total crack length has a value range of [15 mm, 18 mm]. Preferably, the preset total crack length is 15 mm.

[0101] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

[0102] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An automatic control system for a wetting die head capable of improving the uniformity of dispersion and distribution of long glass fibers, characterized in that: include: a die unit including a die body, a heater and a rotating roller; The surface of the die body is provided with a long glass fiber bundle input port, a molten material input port and a long glass fiber reinforced plastic output port, the die body is provided with a first channel and a second channel, the first channel is connected with the long glass fiber bundle input port and the long glass fiber reinforced plastic output port respectively, one end of the second channel is connected with the molten material input port, the other end of the second channel is connected with the first channel through a convergence cavity, an impregnation cavity is provided between the first channel and the long glass fiber reinforced plastic output port; the heater is provided on the side wall of the second channel; the rotating roller is provided in the impregnation cavity, and the surface of the rotating roller is provided with equidistant protrusions; A cooling unit, which is arranged at the output end of the die unit and includes a cold water tank; A traction unit, which is arranged at the output end of the cooling unit and includes a traction machine; A collection unit, comprising an image collection module for collecting the hairiness length on the surface of the long glass fiber bundle and the crack length on the end surface of the long glass fiber reinforced plastic, and a mechanical property collection module for collecting the tensile modulus and tensile strength of the long glass fiber reinforced plastic; A control unit is respectively connected to the die unit, the cooling unit, the traction unit and the collection unit, and is used to increase the rotation speed of the rotating roller under the condition that the wetting of the long glass fiber bundle does not meet the preset standard according to the wetting uniformity characteristic value, or to determine whether the wetting of the long glass fiber bundle meets the preset standard for the second time according to the arrangement evaluation value.

2. The automatic control system for the impregnation die head capable of improving the uniformity of dispersion and distribution of long glass fibers according to claim 1, characterized in that: The control unit determines whether the impregnation of the long glass fiber bundle meets the preset standard according to the impregnation uniformity characteristic value, wherein: If the wetting uniformity characteristic value is less than the first preset wetting uniformity threshold value, the control unit determines that the wetting of the long glass fiber bundle does not meet the preset standard, and increases the rotation speed of the rotating roller according to the difference between the first preset wetting uniformity threshold value and the wetting uniformity characteristic value; If the infiltration uniformity characteristic value is greater than or equal to the first preset infiltration uniformity threshold value and less than the second preset infiltration uniformity threshold value, the control unit determines that the infiltration of the long glass fiber bundle does not meet the preset standard, and determines whether the infiltration of the long glass fiber bundle meets the preset standard for the second time according to the arrangement evaluation value; If the wetting uniformity characteristic value is greater than or equal to the second preset wetting uniformity threshold, the control unit determines that the wetting of the long glass fiber bundle meets the preset standard.

3. The automatic control system for the impregnation die head capable of improving the dispersion and distribution uniformity of long glass fibers according to claim 2, characterized in that: The wet uniformity characteristic value is the average value of the hairiness length on the surface of the long glass fiber bundle.

4. The automatic control system for the impregnation die head capable of improving the uniformity of dispersion and distribution of long glass fibers according to claim 3, characterized in that: The control unit is provided with several speed increasing modes for increasing the speed of the rotating roller, wherein: If the wetting difference is less than the first preset wetting difference, the control unit increases the rotation speed of the rotating roller using a first preset adjustment coefficient; If the wetting difference is greater than or equal to the first preset wetting difference and less than the second preset wetting difference, the control unit increases the rotation speed of the rotating roller using a second preset adjustment coefficient; If the wetting difference is greater than or equal to the second preset wetting difference, the control unit increases the rotation speed of the rotating roller using a third preset adjustment coefficient; The wetting difference is the difference between the first preset wetting uniformity threshold and the wetting uniformity characteristic value.

5. The automatic control system for the impregnation die head capable of improving the uniformity of dispersion and distribution of long glass fibers according to claim 4, characterized in that: The control unit determines whether the infiltration of the long glass fiber bundle meets the preset standard based on the arrangement evaluation value of the long glass fiber bundle. If the arrangement evaluation value is less than the preset arrangement threshold, the control unit determines that the infiltration of the long glass fiber bundle does not meet the preset standard, and determines the adjustment method under the condition that the infiltration of the long glass fiber bundle does not meet the preset standard according to the tensile characteristic value; If the arrangement evaluation value is greater than or equal to the preset arrangement threshold, the control unit determines that the wetting of the long glass fiber bundle meets the preset standard.

6. The automatic control system for the impregnation die head capable of improving the uniformity of dispersion and distribution of long glass fibers according to claim 5, characterized in that: The arrangement evaluation value is obtained by the distance between each long glass fiber filament in the long glass fiber reinforced plastic.

7. The automatic control system for the impregnation die head capable of improving the uniformity of dispersion and distribution of long glass fibers according to claim 6, characterized in that: The control unit determines the adjustment method under the condition that the impregnation of the long glass fiber bundle does not meet the preset standard according to the tensile characteristic value of the long glass fiber reinforced plastic, wherein: If the stretch characteristic value is less than the preset stretch threshold value, the control unit increases the injection pressure of the melt according to the difference between the preset stretch threshold value and the stretch characteristic value; If the stretching characteristic value is greater than or equal to the preset stretching threshold, the control unit reduces the traction rate of the traction machine according to the difference between the stretching characteristic value and the preset stretching threshold; The tensile characteristic value is determined by the tensile modulus of the long glass fiber reinforced plastic and the tensile strength of the long glass fiber reinforced plastic.

8. The automatic control system for the impregnation die head capable of improving the dispersion and distribution uniformity of long glass fibers according to claim 7, characterized in that: The increase amplitude of the injection pressure is positively correlated with the stretch difference, wherein the stretch difference is the difference between a preset stretch threshold and a stretch characteristic value.

9. The automatic control system for the impregnation die head capable of improving the dispersion and distribution uniformity of long glass fibers according to claim 8, characterized in that: Under the first preset condition, the control unit determines the correction method of the injection pressure according to the crack characteristic difference of the long glass fiber reinforced plastic, wherein: If the crack characteristic difference is less than a first preset crack characteristic difference, the control unit uses a first pressure correction coefficient to correct the injection pressure; If the crack characteristic difference is greater than or equal to the first preset crack characteristic difference and less than the second preset crack characteristic difference, the control unit uses a second pressure correction coefficient to correct the injection pressure; If the crack characteristic difference is greater than or equal to the second preset crack characteristic difference, the control unit corrects the injection pressure using a third pressure correction coefficient; The first preset condition is that after the injection pressure of the melt is increased, the crack characteristic value of the long glass fiber reinforced plastic exceeds the preset crack characteristic value; the crack characteristic difference is the difference between the crack characteristic value and the preset crack characteristic value.

10. The automatic control system for the impregnation die head capable of improving the dispersion and distribution uniformity of long glass fibers according to claim 9, characterized in that: The crack characteristic value is determined by the total length of the cracks on the end surface of the long glass fiber reinforced plastic.

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