CN-121118524-B - Woodworking glue fluidity control method based on multi-parameter cooperative optimization

Abstract

The application provides a woodworking glue fluidity control method based on multi-parameter collaborative optimization, which comprises the steps of analyzing fiber orientation angles and micro-warpage heights by adopting a finite element method, calculating glue seam thickness deviation and local stress concentration distribution by combining plate deformation characteristics to obtain a glue seam thickness distribution map and civil glue fluidity, obtaining civil glue viscosity distribution and environmental temperature influence data, combining the glue seam thickness distribution map and the civil glue fluidity, analyzing to obtain glue solution filling differences, edge extrusion rates, glue solution permeation rates and glue solution boundary layers of soil-wood glue in glue seams, verifying laminating time sequence schemes and force distribution parameters by adopting fluid dynamics simulation, and analyzing the glue seam thickness deviation and the glue solution filling differences by combining glue seam interface roughness influence factors to obtain glue seam uniformity and glue solution distribution stability prediction data.

Inventors

• GU XINMING
• XU YONG
• Xiao Changxi

Assignees

• 广东邦尼达化学工业有限公司

Dates

Publication Date

20260508

Application Date

20250828

Claims (6)

1. 1. The carpenter's glue fluidity control method based on multi-parameter cooperative optimization is characterized by comprising the following steps: step 1, acquiring surface data of a plate to obtain a fiber orientation angle and a warping height, and carrying out statistical analysis and numerical fitting treatment on the fiber orientation angle and the warping height to obtain the roughness of a glue line interface; Step 2, constructing three-dimensional grid units of the plate by adopting a finite element method, setting the main material direction of each grid unit according to the fiber orientation angle, applying displacement boundary conditions at grid nodes according to the data of the warp height, obtaining the stress value of each grid unit by analysis, extracting normal stress components perpendicular to the surface of the plate from the stress values, forming local stress concentration distribution data based on the normal stress components, calculating the elastic deformation of each position according to the stress values in the local stress concentration distribution data by using Hooke's law, subtracting the elastic deformation from the initial design thickness of a glue line to obtain actual glue line thickness values, carrying out bilinear interpolation on the actual glue line thickness values of all grid units to generate a continuous glue line thickness distribution map, calculating the thickness gradient from the thickness difference value and the distance of the adjacent positions of the glue line thickness distribution map, calculating the colloid flow speed according to the pressure difference and the colloid viscosity generated by the thickness gradient, carrying out time integration on the colloid flow speed to obtain colloid migration volume, and determining the woodworking fluidity numerical value by the ratio of the colloid migration volume to the total volume; step 3, obtaining woodworking adhesive strength distribution data and environmental temperature data, and combining the adhesive seam thickness distribution map and the woodworking adhesive fluidity numerical value to determine adhesive filling difference and edge extrusion rate of the woodworking adhesive in the adhesive seam, wherein the adhesive filling difference refers to the difference of adhesive filling time in different areas; Step 4, if the edge extrusion rate exceeds a preset threshold, acquiring viscosity measurement data of the woodworking adhesive at different shear rates, calculating the decreasing proportion of the viscosity along with the shear rate as a shear thinning rate, and simultaneously measuring the time required for the viscosity to recover to ninety percent of an initial value after the shearing is stopped as recovery time; the method comprises the steps of adjusting the shear thinning rate according to woodworking adhesive distribution data, obtaining an adjusted glue solution thixotropic property value based on the adjusted shear thinning rate and recovery time, determining control parameters of a pressing process based on the adjusted glue solution thixotropic property value, obtaining pressure values applied by pressing equipment at different positions of a plate, and calculating a force gradient value by dividing the pressure difference value of adjacent positions by the position distance to form force gradient distribution data of the pressing equipment; Step 5, according to the adjusted thixotropic value of the glue solution and the force gradient distribution data of the pressing equipment, combining the geometric constraint condition of the edge of the plate to obtain a pressing time sequence scheme and force distribution parameters; and 6, verifying the pressing time sequence scheme and the force distribution parameters by adopting fluid dynamics simulation.
2. 2. The method for controlling the fluidity of the wood working glue based on the multi-parameter cooperative optimization according to claim 1, wherein the step 1 specifically comprises: the method comprises the steps of obtaining three-dimensional coordinate data of a plate surface point by point through a three-dimensional laser scanning device, calculating the height difference and the horizontal distance between adjacent scanning points based on the three-dimensional coordinate data, and determining the local surface inclination angle; Judging the fiber orientation angle through the direction distribution of the local surface inclination angle, and determining the warping height based on the deviation value of the scanning point height coordinate and the reference plane; Respectively calculating probability density distribution of fiber orientation angles and probability density distribution of warping heights by a kernel density estimation method, and respectively carrying out numerical fitting on the two probability density distribution by a least square method to obtain a fiber orientation angle distribution function and a warping height distribution function; According to the fiber orientation angle distribution function and the warping height distribution function, calculating deformation gradients of all areas of the plate, wherein the deformation gradients are defined as products of warping height differences of adjacent areas and fiber orientation angle differences, and integral operation is carried out on the deformation gradients of all areas to obtain integral deformation characteristic parameters of the plate; Identifying the position of a glue line interface based on the integral deformation characteristic parameters of the plate, extracting the height profile data perpendicular to the interface direction at the position of the glue line interface, calculating the root mean square deviation of the height profile data to generate a local roughness value, and carrying out weighted average on the local roughness value to generate the numerical value of the glue line interface roughness.
3. 3. The method for controlling the fluidity of the wood working glue based on the multi-parameter cooperative optimization according to claim 1, wherein the step 3 specifically comprises: The method comprises the steps of obtaining viscosity measurement values of woodworking glue at different temperatures, obtaining a functional relation between viscosity and temperature by fitting the viscosity measurement values and the temperature data, calculating flow resistance coefficients of all positions by combining thickness data of all positions in a glue seam thickness distribution diagram, calculating average flow speeds of glue solution in glue seams with different thicknesses on the basis of the flow resistance coefficients and the glue seam flowability values, determining filling time of all areas on the basis of the average flow speeds and the glue seam lengths, comparing filling time of adjacent areas to generate glue solution filling difference data, calculating pressure gradient on the basis of pressure difference inside and outside glue seams, and determining edge extrusion rate on the basis of the pressure gradient and the glue seam edge cross section area.
4. 4. The method for controlling the fluidity of a wood adhesive based on the multi-parameter collaborative optimization according to claim 1, wherein the adjusting the shear-thinning rate according to the wood adhesive distribution data and obtaining the adjusted thixotropic value of the adhesive based on the adjusted shear-thinning rate and the recovery time comprises identifying a high viscosity area and a low viscosity area according to the wood adhesive distribution data, increasing the upper limit of the shear rate measuring range for the high viscosity area, decreasing the lower limit of the shear rate measuring range for the low viscosity area, re-measuring the viscosity change in the adjusted shear rate range, calculating the adjusted shear-thinning rate, and obtaining the adjusted thixotropic value of the adhesive by using the product of the adjusted shear-thinning rate and the recovery time.
5. 5. The method for controlling the fluidity of a wood working glue based on the cooperative optimization of multiple parameters according to claim 1, wherein the step 5 further comprises: According to the height deviation and the inclination angle in the geometric constraint condition of the plate edge, calculating a pressure compensation value required by the edge region according to a geometric compensation principle, obtaining the edge region pressure value by adding the pressure compensation value to a central region reference pressure value, obtaining a pressure gradient change rate by subtracting the central region pressure value from the edge region pressure value and dividing the central region pressure value by the distance from the center to the edge, and forming a force distribution parameter comprising the central region pressure value, the edge region pressure value and the pressure gradient change rate.
6. 6. The method for controlling the flowability of a wood working glue based on multi-parameter cooperative optimization according to claim 1, wherein the step of verifying the pressing timing scheme and the force distribution parameters by using hydrodynamic simulation comprises the steps of: constructing a glue line flow calculation domain by adopting a fluid dynamics simulation method, setting pressure boundary conditions of all time nodes according to a pressing time sequence scheme, and generating glue solution speed field and pressure field distribution of glue solution at different moments; the method comprises the steps of calculating a correction coefficient based on the glue joint interface roughness, generating an expected thickness based on the correction coefficient and the glue joint initial design thickness, generating glue joint thickness deviation based on the expected thickness and the glue joint initial design thickness, calculating standard deviation of all position thickness deviation values as glue joint uniformity values based on the glue joint thickness deviation and glue solution filling difference, dividing the standard deviation of filling completion time of each region by average filling time to obtain glue solution distribution stability values, and forming predicted data of glue joint uniformity and glue solution distribution stability.

Description

Woodworking glue fluidity control method based on multi-parameter cooperative optimization Technical Field The invention relates to the technical field of information, in particular to a woodworking glue fluidity control method based on multi-parameter collaborative optimization. Background The application of the woodworking glue in the manufacturing of furniture and wood processing is crucial, and the flow stability of the woodworking glue in the glue line of the jointed boards directly influences the quality and the production efficiency of the jointed boards. The stable glue flow can ensure that the glue line is even and firmly bonded, thereby improving the strength and durability of the wood product. However, the existing method ignores the influence of the fiber direction difference and micro-warpage of the plate material on the flowing of the glue solution in the actual production when processing the complex jointed board scene, so that the quality of the glue joint is unstable, and particularly in the high-precision furniture manufacturing, the strict technological requirements are difficult to meet. In the splicing process, the difference of the fiber directions of adjacent plates can cause uneven distribution of glue flow resistance, thereby affecting the penetration and distribution of glue in glue joints. Especially when the plate is slightly warped, the thickness of the glue line is locally thinned or thickened, and the flowing complexity of glue solution is further increased. For example, in the production of solid wood furniture panels, if the fiber direction of one panel is greatly different from that of an adjacent panel, glue may flow out too quickly in some areas, resulting in uneven edge extrusion rate, and even a void or glue overflow phenomenon in a local glue line. Such uneven flow not only reduces the bond strength, but may also cause quality defects during subsequent lamination. The thixotropic property of the glue solution is used as another key factor and is closely related to the dynamic adjustment of the plate pressing time sequence. If the thixotropic property is not properly controlled, the glue solution may be lost rapidly due to the excessively strong fluidity at the initial stage of lamination, or the glue line cannot be fully filled due to the insufficient fluidity, so that the uniformity and stability of the glue line are affected. Therefore, how to ensure the flow stability and uniform distribution of the glue solution in the glue line by cooperatively optimizing the thixotropic property and the pressing time sequence of the glue solution under the dynamic conditions of the difference of the fiber directions of the plates and the micro-warpage becomes a key problem for improving the quality of the jointed boards. Disclosure of Invention The invention provides a carpenter's glue fluidity control method based on multi-parameter cooperative optimization, which mainly comprises the following steps: The method comprises the steps of obtaining sheet surface data, obtaining fiber orientation angles and micro-warping heights, carrying out statistical analysis based on the fiber orientation angles and the micro-warping heights, determining sheet deformation characteristics and glue line interface roughness, adopting a finite element analysis method to process the fiber orientation angles and the micro-warping heights, calculating glue line thickness distribution and local stress concentration distribution by combining the sheet deformation characteristics, determining soil and wood glue fluidity parameters, obtaining civil glue viscosity distribution data and environment temperature data, combining the glue line thickness distribution and the civil glue fluidity parameters, determining glue filling difference and edge extrusion rate, adjusting glue solution thixotropic property parameters and glue line laminating equipment strength distribution based on the edge extrusion rate and the civil glue viscosity distribution data, combining sheet edge geometric constraint conditions, determining a laminating time sequence scheme and the glue line strength distribution parameters, combining the glue line interface roughness, adjusting the glue line uniformity parameters and glue line distribution stability parameters by fluid dynamics simulation verification. Further, the scanning obtains the surface data of the plate to obtain a fiber orientation angle and a micro-warpage height, and the statistical analysis is performed based on the fiber orientation angle and the micro-warpage height to determine the deformation characteristic and the adhesive joint interface roughness of the plate, including: The method comprises the steps of obtaining three-dimensional coordinate data of a plate surface point by point through a three-dimensional laser scanning device, calculating height differences and horizontal distances between adjacent points based on the three-dimensional coordinate data, determ