Display glass corner high-precision grinding system and method thereof

Abstract

The invention belongs to the technical field of display glass processing, and particularly discloses a display glass corner high-precision grinding system and a method thereof.The device comprises a workbench, a grinding device, a grinding moving support, a pressure adjusting system, a pressure feedback system, a fixing tool, a positioning adjusting device, a positioning detecting system, a power system and a central control system; by means of equidistant grinding, grinding pressure control and processing of process data through a central control system, the grinding process is continuously iteratively optimized, the abrasion loss of a grinding head can be counted, the precision influence caused by the abrasion loss can be eliminated, the consistency and high precision of the edge quality of display glass are guaranteed, and the method is particularly suitable for batch machining of the same specification. Through a pressure-error space-time coupling relationship, position-related pressure compensation along a grinding path, weighted learning of historical grinding data, stability guarantee of system dynamic characteristics and real-time pressure fluctuation compensation are realized.

Description

Technical Field

[0001] The invention belongs to the technical field of display glass processing, and in particular relates to a display glass corner high-precision grinding system and method. Background Art

[0002] In the display glass manufacturing and processing industry, the grinding of glass corners is a crucial link. High-quality corner grinding can not only improve the appearance of the product, but also ensure its physical properties and service life.

[0003] Traditional display glass corner grinding processes are mostly carried out manually or with semi-automatic equipment. In batch processing, it is often difficult to balance efficiency and precision. In addition, wear of the grinding head will lead to a decrease in grinding efficiency and will also affect the grinding precision, making it difficult for the corner quality of the final product to meet the design requirements. During long-term operation, the grinding quality gradually decreases. For example, in the Chinese invention patent with patent announcement number CN106166699B, the edge of the workbench is provided with a slide rail extending along the edge of the glass substrate, and the grinding wheel and the grinding motor are movably arranged on the slide rail along the edge of the glass substrate, and grind in a straight line along the slide rail. However, the grinding wheel (or grinding head) will continue to wear during use, thereby affecting the subsequent grinding amount, and thus easily reducing the uniformity and precision of the grinding effect. Summary of the invention

[0004] In view of the problem that the uniformity and precision of display glass corner grinding in the prior art need to be improved, a display glass corner high-precision grinding system and method are proposed. The present invention provides the following technical solutions:

[0005] A high-precision grinding system for display glass corners, comprising:

[0006] Workbench, used to provide stable support;

[0007] A grinding device, used for grinding the corners of the display glass;

[0008] A grinding movable support, used to form a grinding movable track of the grinding device, and the grinding device is movably connected thereto through a power system;

[0009] The pressure adjustment system is used to adjust the input grinding pressure F of the grinding device on the display glass. 1 ;

[0010] The pressure feedback system is used to feedback the actual grinding pressure F of the grinding device on the display glass. 2 ;

[0011] A fixing tool, used for fixing the display glass, which can be movably arranged on the workbench as a whole;

[0012] A positioning adjustment device, used to adjust the position of the fixing fixture to make different edges of the display glass equidistant from the grinding movement track of the grinding device;

[0013] A positioning detection system, which is used to detect whether the positioning adjustment device displays different edges of the glass at equal distances from the grinding movement track of the grinding device;

[0014] A power system for providing driving support;

[0015] The central control system is used to receive the actual grinding pressure fed back by the pressure feedback system and the positioning detection system to control the operation of the power system. It adjusts the input grinding pressure accordingly through the pressure adjustment system.

[0016] Preferably, it also includes a quality inspection system for inspecting the display glass after grinding, which is connected to the central control system.

[0017] Preferably, the grinding device comprises a grinder and a grinding bracket, wherein the grinder is rotatably connected to the grinding bracket, and the grinding bracket is relatively movably connected to the grinding movable bracket.

[0018] Preferably, the pressure adjustment system comprises an elastic tension device for providing pre-tension to the grinder and a thruster for adjusting the input grinding pressure.

[0019] Preferably, the elastic tension device is a tension spring, one end of which is connected to the grinder, and the other end of which is connected to the grinding bracket.

[0020] Preferably, it also includes a lifting and adjusting device, which is installed and connected to the workbench, and the grinding movable bracket is installed and fixed on the output end of the lifting and adjusting device.

[0021] Preferably, it also includes a grinding head detection device for detecting wear data and external dimension data of the grinding device.

[0022] A method for high-precision grinding of display glass corners is based on a high-precision grinding system for display glass corners, and the steps include:

[0023] S1, pretreatment;

[0024] S11. Fix the display glass on the fixed fixture;

[0025] S12, matching the display glass with the grinding movable frame, so that the outer contour of the display glass and the grinding moving track formed by the grinding movable frame form a similar body relationship;

[0026] S2, basic positioning;

[0027] S21, moving the fixed tooling to a specified state through the positioning and adjusting device, the specified state includes:

[0028] S211, if the number of edges to be processed n=1, move until the edge to be processed is parallel to a part of the grinding movement trajectory;

[0029] S212, if the number of edges to be processed n≥2, move until the centroid of the display glass and the grinding movement track coincide with each other, and each edge is equidistant from the grinding movement track;

[0030] S3. Adjust the actual grinding pressure F of the grinding device 2 ;

[0031] S31, adjust the input grinding pressure F through the pressure adjustment system 1 ;

[0032] S4, grinding along the grinding moving track at equal intervals; during grinding, the actual grinding pressure is recorded in real time through the pressure feedback system;

[0033] S5, obtain the data after grinding; test the display glass after grinding through the quality inspection system, and transmit the quality inspection data to Central Control system;

[0034] S6. Iterative optimization and adjustment of the central control system;

[0035] According to the correspondence between the grinding error obtained by the previous piece of glass and the actual grinding pressure at each point on the path, the actual grinding pressure is adjusted in real time by adjusting the input grinding pressure in real time, ensuring that the grinding error obtained by the previous piece of glass is continuously reduced or controlled within a smaller range during the subsequent grinding process.

[0036] Preferably, an adaptive pressure regulation formula system is constructed based on iterative learning control:

[0037] Discretize the grinding trajectory into m positions, for the kth piece of glass:

[0038] Δe (k) (i) = y d (i)-y (k) (i),i=1,2,…,m

[0039] Where: y d (i) is the target size of the i-th point, y (k) (i) is the actual size of the kth piece after grinding, Δe (k) (i) is the error of the i-th point in the k-th slice;

[0040] The pressure sensitivity matrix is ​​established through experimental data:

[0041]

[0042] Where: S∈R^{m×m} is the pressure influence matrix (diagonally dominant), ε is the system noise;

[0043] Iterative learning control law:

[0044]

[0045] Where: γ(i) is the position-dependent learning rate (recommended value is 0.3-0.8), Φ(x) = tanh(x / τ), error transformation function with saturation characteristics, τ = error saturation threshold, Pressure influence weight function, β = 10 -3 , F c = critical pressure value;

[0046] Spectral radius condition:

[0047] ρ(I-ΓS)<1

[0048] Where: -Γ=diag(γ(1),...,γ(m)), S must satisfy diagonal dominance: |s ii |∑ j≠i ||;

[0049] Multiple sheets of glass are recursively updated using exponentially weighted memory:

[0050]

[0051] Where λ∈(0,1) is the forgetting factor.

[0052] Preferably, in step S6, real-time pressure compensation is performed:

[0053] F 2 (k) (i) = F 1 (k) (i) -k·Δx (k) (i)+μ·v (k) (i)+η (k) (i)

[0054] Compensation:

[0055] ΔF 1 (k) (i) = k·Δx (k) (i) -μ·v (k) (i)-E[η (k) (i)]

[0056] Among them, k = elastic coefficient of the tension spring, Δx = displacement of the grinding head, μ = friction coefficient, and v = grinding movement speed.

[0057] Compared with the prior art, the present invention has the following beneficial effects:

[0058] 1. The present application sets a grinding movable bracket to make different edge lines of the display glass equidistant from the grinding moving track of the grinding device, ensuring that the grinding device always maintains the same contact position with the display glass on the grinding moving track, reducing the difference in grinding between different edge lines, which is conducive to improving uniformity and accuracy. ;

[0059] 2. According to the corresponding relationship between the grinding error of the previous piece of glass and the actual grinding pressure at each point on the path, the actual grinding pressure is adjusted in real time by adjusting the input grinding pressure in real time, so as to ensure that the grinding error of the previous piece of glass is continuously reduced or controlled within a smaller range in the subsequent grinding process;

[0060] 3. The grinding process is continuously optimized iteratively, which can take into account the wear of the grinding head and eliminate the impact on the accuracy it brings, ensuring the consistency and high precision of the edge quality of the display glass, which is especially suitable for batch processing of the same specifications. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 It is a schematic diagram of the process structure of the present invention; DETAILED DESCRIPTION

[0062] In order to enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention is clearly and completely described below in conjunction with the accompanying drawings of the present invention. The directional words mentioned in the following embodiments, such as "up", "down", "left" and "right", etc., are only reference to the directions of the accompanying drawings. Therefore, the directional words used are used to illustrate rather than limit the invention.

[0063] Example 1

[0064] In this embodiment, the high-precision grinding system for display glass corners includes:

[0065] Workbench, used to provide stable support;

[0066] A grinding device, used for grinding the corners of the display glass;

[0067] A grinding movable support, used to form a grinding movable track of the grinding device, and the grinding device is movably connected thereto through a power system;

[0068] A pressure adjustment system for adjusting the input grinding pressure of the grinding device on the display glass;

[0069] A pressure feedback system, which is used to feedback the actual grinding pressure of the grinding device on the display glass;

[0070] A fixing tool, used for fixing the display glass, which can be movably arranged on the workbench as a whole;

[0071] A positioning adjustment device, used to adjust the position of the fixing fixture to make different edges of the display glass equidistant from the grinding movement track of the grinding device;

[0072] A positioning detection system, which is used to detect whether the positioning adjustment device has the same distance between different edges of the displayed glass and the grinding movement track of the grinding device;

[0073] A power system for providing driving support;

[0074] The central control system is used to receive the pressure feedback system and the positioning detection system to control the operation of the power system. Force Feedback The system feeds back the actual grinding pressure and adjusts the input grinding pressure accordingly through the pressure adjustment system.

[0075] When different edge lines are equidistant from the grinding moving track of the grinding device, it will be ensured that the grinding device always maintains the same contact position with the display glass on the grinding moving track, reducing the difference in grinding between different edge lines, which is conducive to improving uniformity and accuracy.

[0076] Example 2

[0077] On the basis of Example 1, the grinding device includes a grinder and a grinding bracket. The grinder is rotatably connected to the grinding bracket, and the grinding bracket can move horizontally along a grinding moving trajectory on a grinding moving bracket. Under the condition of ensuring that the grinding moving trajectory is equidistant from the display glass, the grinding moving bracket can be customized to different specifications according to different display glasses to adapt to the processing of display glasses of different specifications.

[0078] The pressure adjustment system comprises an elastic tension device for providing pre-tension to the grinder and a thruster for adjusting the input grinding pressure.

[0079] The elastic tension device adopts a tension spring, one end of which is connected to the grinder, and the other end is connected to the grinding bracket.

[0080] Example 3

[0081] On the basis of Example 1 or 2, it also includes a quality inspection system for inspecting the display glass after grinding, which is connected to the central control system.

[0082] Furthermore, it also includes a lifting and adjusting device, which is installed and connected to the workbench, and the grinding movable bracket is installed and fixed on the output end of the lifting and adjusting device.

[0083] Furthermore, it also includes a grinding head detection device for detecting wear data and external dimension data of the grinding device.

[0084] Additionally, the grinder can be set to be able to move horizontally and vertically relative to the grinding movement trajectory of the grinding bracket to finely adjust the position of the grinder, so as to perform fine adjustment and compensation. It can be driven by a linear drive device belonging to the power system, which is mainly applicable to scenarios of adjustment or replacement of the grinding head when the wear amount is too large.

[0085] In addition, the grinding device, power system, lifting adjustment device, etc. in this application can each adopt existing mature components, and the realization of their functions is relatively easy for those skilled in the art and is not the key point emphasized in this application, so they will not be elaborated here.

[0086] Embodiment 4

[0087] A method for high-precision grinding of the edges and corners of display glass, which is based on a high-precision grinding system for the edges and corners of display glass, and its steps include:

[0088] S1. Pretreatment;

[0089] S11. Fix the display glass on the fixing tooling;

[0090] S12. Match the display glass with the grinding movement frame so that the outer contour of the display glass and the grinding movement trajectory formed by the grinding movement frame form a similar body relationship;

[0091] S2. Basic positioning;

[0092] S21. Move the fixing tooling to the specified state through the positioning adjustment device, and the specified state includes:

[0093] S211. If the number of sides to be processed n = 1, move to a local parallelism between the side to be processed and the grinding movement trajectory;

[0094] S212. If the number of sides to be processed n ≥ 2, move to the centroid of the display glass and the grinding movement trajectory to coincide with each other, and each side is equidistant from the grinding movement trajectory;

[0095] S3. Adjust the actual grinding pressure F of the grinding device 2 ;

[0096] S31. Adjust the input grinding pressure F through the pressure adjustment system 1 ;

[0097] S4. Grind along the grinding movement trajectory at an equal distance and maintain the same speed; during grinding, the actual grinding pressure F is recorded in real time through the pressure feedback system 2 ;

[0098] S5. Obtain the data after grinding; detect the display glass after grinding through the quality inspection system, and transmit the quality inspection data to the central control system;

[0099] S6. Iterative optimization and adjustment of the central control system;

[0100] According to the correspondence between the grinding error obtained by the previous piece of glass and the actual grinding pressure at each point on the path, the actual grinding pressure is adjusted in real time by adjusting the input grinding pressure in real time, ensuring that the grinding error obtained by the previous piece of glass is continuously reduced or controlled within a smaller range during the subsequent grinding process.

[0101] During the next grinding, the height h of the grinding device is adjusted by driving the lifting and adjusting device according to the external dimension data to ensure that the grinding device is in contact with the display glass.

[0102] An adaptive pressure regulation formula system is constructed based on iterative learning control, specifically:

[0103] Discretize the grinding track into m positions at the same height h. For the kth piece of glass:

[0104] Δe (k) (i) = y d (i)-y (k) (i),i=1,2,…,m

[0105] Where: y d (i) is the target size of the i-th point, y (k) (i) is the actual size of the kth piece after grinding, Δe (k) (i) is the error of the i-th point of the k-th sheet; the pressure sensitivity matrix is ​​established through experimental data:

[0106]

[0107] Where: S∈R^{m×m} is the pressure influence matrix (diagonally dominant), ε is the system noise;

[0108] Iterative learning control law:

[0109]

[0110] Where: γ(i) is the position-dependent learning rate (recommended value is 0.3-0.8), Φ(x) = tanh(x / τ), error transformation function with saturation characteristics, τ = error saturation threshold, Pressure influence weight function, β = 10 -3 , F c = critical pressure value;

[0111] In order to ensure high dynamic stability, the spectral radius condition must be met:

[0112] ρ(I-ΓS)<1

[0113] Where: -Γ=diag(γ(1),...,γ(m)), S must satisfy diagonal dominance: |s ii |∑ j≠i ||;

[0114] Construct the elastic pressure balance equation:

[0115] F 2 =F 1 -k·Δx+μ·v

[0116] Among them, k = elastic coefficient of the tension spring, Δx = displacement of the grinding head, μ = friction coefficient, and v = grinding movement speed.

[0117] Real-time pressure compensation based on the elastic pressure balance equation:

[0118] F 2 (k) (i) = F 1 (k) (i) -k·Δx (k) (i)+μ·v (k) (i)+η (k) (i)

[0119] Compensation:

[0120] ΔF 1 (k) (i) = k·Δx (k) (i) -μ·v (k) ((i)-E[η (k) (i)]

[0121] Among them, k = elastic coefficient of the tension spring, Δx = displacement of the grinding head, μ = friction coefficient, and v = grinding movement speed.

[0122] Multiple sheets of glass are recursively updated using exponentially weighted memory:

[0123]

[0124] Where λ∈(0,1) is the forgetting factor.

[0125] In actual application, the learning rate γ is 0.5±0.3 (adjusted according to the condition number of the S matrix), the forgetting factor λ is 0.6-0.8, and it is updated after each piece of glass is ground, and the saturation threshold τ is 1.5 times the allowable error; and the error-pressure database can be established through the central control system.

[0126] Furthermore, the algorithm and processing data can be shared by multiple devices through data transmission, reducing the initial optimization time of new equipment, and because the positioning accuracy of the device itself can also be ensured by devices such as three-coordinate and laser interferometers, it can achieve higher precision itself; on this basis, through this method, the wear of the grinding head can be taken into account and the impact of the wear on the precision can be eliminated, thereby ensuring the consistency and high precision of the edge quality of the display glass, which is particularly suitable for batch processing of the same specifications.

[0127] Through the spatiotemporal coupling relationship of pressure-error, position-related pressure compensation along the grinding path, weighted learning of historical grinding data, stability guarantee of system dynamic characteristics, and real-time pressure fluctuation compensation are achieved.

Claims

1. A high-precision grinding system for display glass corners, characterized in that: include: Workbench, used to provide stable support; A grinding device, used for grinding the corners of the display glass; A grinding movable support, used to form a grinding movable track of the grinding device, and the grinding device is movably connected thereto through a power system; A pressure adjustment system, which is used to adjust the input grinding pressure F1 of the grinding device acting on the display glass; A pressure feedback system, which is used to feedback the actual grinding pressure F2 of the grinding device on the display glass; A fixing tool, used for fixing the display glass, which can be movably arranged on the workbench as a whole; A positioning adjustment device, used to adjust the position of the fixing fixture to make different edges of the display glass equidistant from the grinding movement track of the grinding device; A positioning detection system, which is used to detect whether the positioning adjustment device displays different edges of the glass at equal distances from the grinding movement track of the grinding device; A power system for providing driving support; The central control system is used to receive the actual grinding pressure fed back by the pressure feedback system and the positioning detection system to control the operation of the power system. It adjusts the input grinding pressure accordingly through the pressure adjustment system.

2. The display glass corner high-precision grinding system according to claim 1, characterized in that: It also includes a quality inspection system for inspecting the display glass after grinding, which is connected to the central control system.

3. The display glass corner high-precision grinding system according to claim 1, characterized in that: The grinding device comprises a grinder and a grinding bracket, wherein the grinder is rotatably connected to the grinding bracket, and the grinding bracket is relatively movably connected to the grinding movable bracket.

4. The display glass corner high-precision grinding system according to claim 3, characterized in that: The pressure adjustment system comprises an elastic tension device for providing pre-tension for the grinder and a thruster for adjusting the input grinding pressure.

5. The display glass corner high-precision grinding system according to claim 4, characterized in that: The elastic tension device adopts a tension spring, one end of which is connected to the grinder, and the other end is connected to the grinding bracket.

6. The display glass corner high-precision grinding system according to claim 1, characterized in that: It also includes a lifting and adjusting device, which is installed and connected to the workbench, and the grinding movable bracket is installed and fixed on the output end of the lifting and adjusting device.

7. The display glass corner high-precision grinding system according to claim 1, characterized in that: It also includes a grinding head detection device for detecting wear data and external dimension data of the grinding device.

8. A method for high-precision grinding of display glass corners, characterized in that: The high-precision grinding system for display glass corners according to claim 1 comprises the following steps: S1, pretreatment; S11. Fix the display glass on the fixed fixture; S12, matching the display glass with the grinding movable frame, so that the outer contour of the display glass and the grinding moving track formed by the grinding movable frame form a similar body relationship; S2, basic positioning; S21, moving the fixed tooling to a specified state through the positioning and adjusting device, the specified state includes: S211, if the number of edges to be processed n=1, move until the edge to be processed is parallel to a part of the grinding movement trajectory; S212, if the number of edges to be processed n≥2, move until the centroid of the display glass and the grinding movement track coincide with each other, and each edge is equidistant from the grinding movement track; S3, adjusting the actual grinding pressure F2 of the grinding device; S31, adjusting the input grinding pressure F1 through the pressure adjustment system; S4, grinding along the grinding moving track at equal intervals; during grinding, the actual grinding pressure is recorded in real time through the pressure feedback system; S5, obtaining the data after grinding; testing the display glass after grinding through the quality inspection system, and transmitting the quality inspection data to the central control system; S6. Iterative optimization and adjustment of the central control system; According to the correspondence between the grinding error obtained by the previous piece of glass and the actual grinding pressure at each point on the path, the actual grinding pressure is adjusted in real time by adjusting the input grinding pressure in real time, ensuring that the grinding error obtained by the previous piece of glass is continuously reduced or controlled within a smaller range during the subsequent grinding process.

9. The method for high-precision grinding of display glass corners according to claim 7, characterized in that: Construct an adaptive pressure regulation formula system based on iterative learning control: Discretize the grinding trajectory into m positions, for the kth piece of glass: Δe (k) (i)=y d (i)-y (k) (i),i=1,2,…,m Where: y d (i) is the target size of the i-th point, y (k) (i) is the actual size of the kth piece after grinding, Δe (k) (i) is the error of the i-th point in the k-th slice; The pressure sensitivity matrix is ​​established through experimental data: Where: S∈R^{m×m} is the pressure influence matrix (diagonally dominant), ε is the system noise; Iterative learning control law: Where: γ(i) is the position-dependent learning rate (recommended value is 0.3-0.8), Φ(x) = tanh(x / τ), error transformation function with saturation characteristics, τ = error saturation threshold, Pressure influence weight function, β = 10 -3 , F c = critical pressure value; Spectral radius condition: ρ(I-ΓS)<1 Where: -Γ=diag(γ(1),...,γ(m)), S must satisfy diagonal dominance: |s ii |∑ j≠i ||; Multiple sheets of glass are recursively updated using exponentially weighted memory: Where λ∈(0,1) is the forgetting factor.

10. The method for high-precision grinding of display glass corners according to claim 7, characterized in that: In step S6, real-time pressure compensation is performed: F2 (k) (i)=F1 (k) (i)-k·Δx (k) (i)+μ·v (k) (i)+η (k) (i) Compensation: ΔF1 (k) (i)=k·Δx (k) (i)-μ·v (k) (i)-E[η (k) (i)] Among them, k = elastic coefficient of the tension spring, Δx = displacement of the grinding head, μ = friction coefficient, and v = grinding movement speed.

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