A screen printing machine frame clamping device and its control method

Abstract

This invention relates to the field of screen printing technology, specifically to a screen printing frame clamping device and its control method for a screen printing machine. This application achieves triple clamping of the screen frame. First, an electromagnetic adsorption clamping mechanism is controlled to adsorb and fix the screen frame, achieving first-level clamping. Then, a motor drives the clamping mechanism to rotate, causing one clamping base to move towards the other, achieving second-level clamping. Subsequently, when one clamping base moves towards the other, an elastic pull-back clamping mechanism generates a pull-back force, causing the two clamping bases to move towards each other, further achieving clamping of the screen frame and adjustment of the dynamic clamping force. This application increases system redundancy through triple clamping. Simultaneously, by introducing a dynamic compensation force system formed by spring pull-back, it actively counteracts the periodic external forces during the printing process, providing hardware assurance for achieving ultra-high precision registration.

Description

Technical Field

[0001] This invention relates to the field of screen printing technology, specifically to a screen printing machine frame clamping device and its control method. Background Technology

[0002] Current screen printing machine frame fixing solutions mainly include mechanical quick clamps and cylinder clamping. Mechanical quick clamps use eccentric wheels or cam handles for manual, rapid locking; however, this method makes clamping force uncontrollable. Excessive clamping force can easily cause deformation of the aluminum alloy frame or failure of the screen to be stretched, while insufficient clamping force directly leads to displacement. Cylinder clamping uses cylinder push rods on one or both sides of the frame to clamp it. While this method can control the clamping force within a fixed range, it cannot provide "adaptive" and precise force control based on frame specifications and process requirements. It also cannot effectively counteract the periodic lateral shearing force and vibration generated by the reciprocating motion of the squeegee during printing. This results in "micron-level creep displacement" of the frame, which accumulates into visible registration deviations, ultimately reducing the yield of printed products. Summary of the Invention

[0003] This invention provides a screen printing machine frame clamping device and its control method, which effectively solves the problem that existing screen printing machine clamping devices cannot accurately control the clamping force of the screen frame during dynamic printing.

[0004] According to the first aspect, one embodiment provides a screen printing machine frame clamping device, including: a controller, an electromagnetic adsorption clamping mechanism, a motor-driven clamping mechanism, and an elastic pull-back clamping mechanism. The electromagnetic adsorption clamping mechanism includes two symmetrically arranged clamping bases and an electromagnetic block disposed on the clamping bases; the clamping bases are used for initial positioning of the mesh frame; the electromagnetic block is disposed on the clamping bases and is used to adsorb and fix the mesh frame after the initial positioning is completed. The motor-driven clamping mechanism is connected to the clamping base on one side of the electromagnetic adsorption clamping mechanism. The motor-driven clamping mechanism is used to drive the clamping base on one side to move to the clamping base on the other side. The elastic pull-back clamping mechanism is disposed on the clamping base on the other side of the electromagnetic adsorption clamping mechanism; the elastic pull-back clamping mechanism and the motor-driven clamping mechanism are disposed at the same end of the clamping base and are connected to the motor-driven clamping mechanism; when the motor-driven clamping mechanism drives the clamping base on one side to move to the clamping base on the other side, the elastic pull-back clamping mechanism generates a pull-back force, and the elastic pull-back clamping mechanism is used to move the clamping base on the other side to the clamping base on one side through the pull-back force; The controller is electrically connected to the electromagnetic block and the motor-driven clamping mechanism respectively. The controller is used to control the power-on of the electromagnetic block and to control the movement of the motor-driven clamping mechanism.

[0005] In one feasible implementation, the motor-driven clamping mechanism includes a drive motor, a lead screw, and a lead screw nut. The drive motor is fixedly mounted on the screen printing machine, and the drive shaft of the drive motor is coaxially connected to the lead screw; the lead screw nut is fixedly connected to the clamping base on one side, and the lead screw and the lead screw nut cooperate with each other.

[0006] In one feasible implementation, the motor-driven clamping mechanism further includes a first clamping block and a guide rail; the first clamping block is connected to the lead screw nut. One end of the guide rail is fixedly connected to the first clamping block, and the other end of the guide rail is fixedly connected to the elastic pull-back clamping mechanism.

[0007] In one feasible implementation, the elastic pull-back clamping mechanism includes a connecting structure, a second clamping block, an elastic element, and a fixing element; The connecting structure is connected to the clamping base on the other side; The fastener is fixedly mounted on the screen printing machine; The other end of the guide rail passes through the fixing member and is fixedly connected to the connecting structure by the second clamping block; One end of the elastic element is connected to the fixing element, and the other end of the elastic element is connected to the connecting structure.

[0008] In one feasible implementation, two motor-driven clamping mechanisms are provided, with each of the two motor-driven clamping mechanisms respectively located at both ends of the clamping base on one side.

[0009] In one feasible implementation, two elastic pull-back clamping mechanisms are provided, and the two elastic pull-back clamping mechanisms are respectively provided at both ends of the clamping base on the other side; The elastic pull-back clamping mechanism and the motor-driven clamping mechanism, located at the same end of the clamping base, are connected.

[0010] According to a second aspect, one embodiment provides a control method for a screen printing machine frame clamping device, wherein the frame clamping device described above is used to clamp and control the frame, the method comprising: Obtain the placement signal of the wire frame, and trigger a clamping command based on the placement signal; The electromagnetic adsorption clamping mechanism is controlled to adsorb and clamp the wire frame according to the clamping command; The moving distance of the motor-driven clamping mechanism is determined according to the preset model of the mesh frame, and the motor-driven clamping mechanism is controlled to drive the clamping base on one side to move the moving distance to the clamping base on the other side. After the clamping base on one side of the motor-driven clamping mechanism moves the distance to the clamping base on the other side, the elastic pull-back clamping mechanism generates a pull-back force, which pulls the clamping base on the other side back to the clamping base on one side.

[0011] In one feasible implementation, the control method further includes: When the scraper acts on the mesh plate along the clamping base on one side to the clamping base on the other side, the pull-back force generated by the elastic pull-back clamping mechanism is increased. The increased pullback force pulls the clamping base on the other side back to the clamping base on one side, so as to counteract the displacement tendency generated when the scraper acts on the mesh plate.

[0012] In one feasible implementation, the motor-driven clamping mechanism includes a drive motor, a lead screw, and a lead screw nut. The drive motor is fixedly mounted on the screen printing machine, and the drive shaft of the drive motor is coaxially connected to the lead screw. The lead screw nut is fixedly connected to the clamping base on one side, and the lead screw and the lead screw nut cooperate with each other. The control of the motor-driven clamping mechanism to move the clamping base on one side to the clamping base on the other side by the specified distance includes: The drive motor is controlled to drive the lead screw to rotate in a first direction, thereby causing the lead screw nut to move the clamping base on one side to the clamping base on the other side by the specified distance.

[0013] According to a third aspect, one embodiment provides a computer-readable storage medium storing a computer program that can be executed by a processor to implement the method described above.

[0014] According to the above embodiment, a screen printing machine frame clamping device and its control method, by triple clamping the screen frame, firstly, after the screen frame is placed between clamping bases, the controller controls the electromagnetic adsorption clamping mechanism to adsorb and fix the screen frame, achieving the first clamping; then, the controller controls the motor to drive the clamping mechanism to rotate, causing one clamping base to move towards the other clamping base, reducing the distance between the two clamping bases, achieving the second clamping of the screen frame; subsequently, since an elastic pull-back clamping mechanism is installed on the other clamping base, when the clamping base moves from one side to the other, the elastic pull-back clamping mechanism generates a pull-back force, which causes the other clamping base to move towards the one clamping base, further achieving clamping of the screen frame, and enabling dynamic adjustment of the clamping force. By adopting the solution of this application, the entire clamping process is automatically completed by the controller without any manual mechanical adjustment. Furthermore, the triple clamping increases the redundancy of the system. Even if one system fails occasionally, the other two can still provide basic fixation, improving safety. At the same time, by introducing a dynamic compensation force system formed by spring pull-back, the periodic external forces of the printing process are actively countered, fundamentally solving the problem of "micro-displacement" of the screen frame and providing hardware guarantee for achieving ultra-high precision registration. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of a screen printing machine frame clamping device provided in this embodiment; Figure 2 This is a schematic diagram of the clamping device with a wire mesh frame provided in this embodiment; Figure 3 This is a flowchart illustrating a control method for a screen printing machine frame clamping device provided in this embodiment.

[0016] Reference numerals: 10, electromagnetic adsorption clamping mechanism; 11, electromagnet; 12, clamping base; 20, motor-driven clamping mechanism; 21, drive motor; 22, lead screw; 23, lead screw nut; 24, first clamping block; 25, guide rail; 30, elastic pull-back clamping mechanism; 31, elastic element; 32, connecting element; 33, second clamping block; 34, fixing element; 40, mesh frame. Detailed Implementation

[0017] The present invention will now be described in further detail with reference to specific embodiments and accompanying drawings. Similar elements in different embodiments are referred to by associated similar element reference numerals. In the following embodiments, many details are described to facilitate a better understanding of this application. However, those skilled in the art will readily recognize that some features may be omitted in different situations, or may be replaced by other elements, materials, or methods. In some cases, certain operations related to this application are not shown or described in the specification. This is to avoid obscuring the core parts of this application with excessive description. For those skilled in the art, detailed description of these related operations is not necessary; they can fully understand the related operations based on the description in the specification and general technical knowledge in the art.

[0018] Furthermore, the features, operations, or characteristics described in the specification can be combined in any suitable manner to form various embodiments. At the same time, the steps or actions in the method description can be rearranged or adjusted in a manner obvious to those skilled in the art. Therefore, the various orders in the specification and drawings are only for the clear description of a particular embodiment and do not imply a necessary order, unless otherwise stated that a particular order must be followed.

[0019] The serial numbers assigned to components in this document, such as "first" and "second," are used only to distinguish the described objects and have no sequential or technical meaning. The terms "connection" and "linkage" used in this application, unless otherwise specified, include both direct and indirect connections (linkages).

[0020] In high-precision screen printing, especially in multi-color or high-speed printing, the absolute stability of the screen frame is the cornerstone of ensuring printing accuracy. However, the core challenge of existing clamping technologies lies in their insufficient "static fixation" and "dynamic interference resistance" capabilities. Specifically, traditional clamping structures can fix the screen frame in a static state, but they cannot effectively counteract the periodic lateral shearing force and vibration generated by the reciprocating motion of the squeegee during printing. This leads to "micron-level creep displacement" of the screen frame, which accumulates into visible registration deviations, a major cause of low yield rates in high-end printing. Furthermore, existing clamping devices rely heavily on worker experience or constant air pressure, resulting in inaccurate clamping force control. Excessive clamping force can easily cause deformation of the aluminum alloy screen frame or screen failure, while insufficient clamping force directly causes displacement. Therefore, it is impossible to achieve "adaptive" and precise force control based on screen frame specifications and process requirements. In addition, when dealing with multi-variety, small-batch production and frequent changes to different sized screen frames, existing equipment suffers from cumbersome fixture adjustments, poor positioning consistency, and long production preparation times. In this application, a screen printing machine frame clamping device and its control method are proposed to solve the above-mentioned problems.

[0021] refer to Figure 1This embodiment provides a screen printing machine frame 40 clamping device, including: a controller, an electromagnetic adsorption clamping mechanism 10, a motor-driven clamping mechanism 20, and an elastic pull-back clamping mechanism 30. The electromagnetic adsorption clamping mechanism 10 includes two symmetrically arranged clamping bases 12 and an electromagnetic block disposed on each clamping base 12. The clamping bases 12 are used for initial positioning of the screen frame 40. The electromagnetic blocks, disposed on the clamping bases 12, are used to adsorb and fix the screen frame 40 after initial positioning. The motor-driven clamping mechanism 20 is connected to one clamping base 12 of the electromagnetic adsorption clamping mechanism 10, and is used to drive the clamping base 12 on one side to move to the clamping base 12 on the other side. The elastic pull-back clamping mechanism 30 is disposed on the other clamping base of the electromagnetic adsorption clamping mechanism 10. On the base 12, the elastic pull-back clamping mechanism 30 and the motor-driven clamping mechanism 20 are disposed at the same end of the clamping base 12 and connected to the motor-driven clamping mechanism 20. When the motor-driven clamping mechanism 20 drives the clamping base 12 on one side to move to the clamping base 12 on the other side, it causes the elastic pull-back clamping mechanism 30 to generate a pull-back force. The elastic pull-back clamping mechanism 30 is used to move the clamping base 12 on the other side to the clamping base 12 on one side through the pull-back force. The controller is electrically connected to the electromagnetic block and the motor-driven clamping mechanism 20 respectively. The controller is used to control the power-on of the electromagnetic block and also to control the movement of the motor-driven clamping mechanism 20.

[0022] Specifically, the screen frame 40 clamping device in this embodiment uses a controller to control a triple clamping mechanism to construct a composite force clamping system that is "actively pre-tightened, dynamically following, and closed-loop controllable." This achieves intelligent clamping with dynamic following compensation for the screen frame 40, not only firmly locking the screen frame 40 in a static state but also actively resisting external forces during dynamic printing, achieving "zero displacement" fixation and improving the automation level of plate changing. Specifically, an array of electromagnets 11 (or a large-area electromagnetic chuck) are embedded in the mounting plane of the clamping base 12. After being powered on by the controller, they generate a strong adsorption force perpendicular to the mounting surface, quickly flattening the back of the screen frame 40 and making it completely fit with the reference surface of the screen printing machine, eliminating the initial gap and laying the foundation for high-precision printing. Subsequently, the controller controls the motor-driven clamping mechanism 20 to provide an actively adjustable main clamping force. Specifically, the motor-driven clamping mechanism 20 is installed at one end of one of the two symmetrically arranged clamping bases 12. When the controller controls the motor-driven clamping mechanism 20 to move, it can drive the clamping base 12 connected to it to move towards the other clamping base 12, so that the clamping force between the two clamping bases 12 can clamp the frame of the mesh frame 40. The drive motor 21 in the motor-driven clamping mechanism 20 has a built-in encoder that provides real-time feedback of the stroke, and the current loop feedback can indirectly monitor the clamping force. Finally, since the elastic pull-back clamping mechanism 30 and the motor-driven clamping mechanism 20 are interconnected, when the motor-driven clamping mechanism 20 drives one clamping base 12 to move towards the other clamping base 12, the elastic element 31 in the elastic pull-back clamping mechanism 30 will be stretched, thereby generating a force opposite to the stretching direction (i.e., pull-back force). When the drive motor 21 continues to run a small stroke, the pull-back force further increases. This pull-back force will drive the other clamping base 12 connected to the elastic pull-back clamping mechanism 30 to pull back towards the clamping base 12 connected to the motor-driven clamping mechanism 20, further clamping the mesh frame 40 and forming a pre-tightening of the mesh frame 40. The entire clamping force is controlled by the motor current threshold to ensure accurate and repeatable force. In practical applications, the electromagnetic block in the electromagnetic adsorption clamping mechanism 10 can also be replaced by a vacuum adsorption platform (with an adsorption hole array on the base connected to a vacuum generator), which can also achieve rapid surface bonding and positioning of the mesh frame 40.

[0023] During the printing process, when the squeegee applies a force F_squeepee to the screen, it tends to cause a slight displacement Δx in the squeegee's moving direction. This displacement tendency causes the elastic pull-back clamping mechanism 30 on one side to be further stretched, instantly increasing the pull-back force F_spring; simultaneously, the spring pull-back force on the other side decreases accordingly, but remains greater than zero. This dynamically changing pull-back force, together with the electromagnetic adsorption force and the motor's static clamping force, forms an adaptive adjustment net, firmly locking the squeegee 40 and suppressing the displacement Δx. At the end of printing, the controller controls the drive motor 21 of the clamping mechanism 20 to rotate in the opposite direction, causing the clamping base 12 to retract to its initial open position, completely releasing the spring pull-back preload. Subsequently, the electromagnetic adsorption unit is powered off, allowing the operator to easily remove the squeegee 40.

[0024] The solution proposed in this application automates the clamping process, with the clamping force precisely controlled by the motor current. This eliminates human error and over-clamping damage, ensuring consistency in each clamping operation. Furthermore, the clamping stroke and force can be adjusted via a program, eliminating the need for any manual mechanical adjustments. This allows for compatibility with screen frames 40 of different sizes and thicknesses, reducing changeover time by over 50%, making it ideal for flexible production needs. In addition, by introducing a dynamic compensation force system formed by spring pullback, the system actively counteracts the periodic external forces during the printing process, fundamentally solving the persistent problem of "micro-displacement" in the screen frame 40 and providing hardware support for achieving ultra-high precision registration.

[0025] Furthermore, such as Figure 2 As shown, the motor-driven clamping mechanism 20 includes a drive motor 21, a lead screw 22, and a lead screw 22 nut; the drive motor 21 is fixedly mounted on the screen printing machine, and the drive shaft of the drive motor 21 is coaxially connected to the lead screw 22; the lead screw 22 nut is fixedly connected to the clamping base 12 on one side, and the lead screw 22 and the lead screw 22 nut cooperate with each other.

[0026] Specifically, in the motor-driven clamping mechanism 20, the drive motor 21 can be fixedly connected to the base of the screen printing machine, that is, the drive motor 21 is fixedly mounted on the screen printing machine, and the output shaft of the drive motor 21 is coaxially connected to the lead screw 22. When the controller controls the output shaft of the drive motor 21 to rotate in the forward direction, the lead screw 22 also rotates in the forward direction. At the same time, the lead screw 22 nut, which cooperates with the lead screw 22, moves forward or backward along the axis of the lead screw 22 while the lead screw 22 rotates. Since the lead screw 22 nut is fixedly connected to the end of one of the clamping bases 12, when the drive motor 21 drives the lead screw 22 to rotate in the forward direction, it drives the lead screw 22 nut towards the other clamping base 12 (i.e., Figure 2When the movement occurs (in the direction indicated by the dashed arrow), the clamping base 12, which is fixedly connected to the nut of the lead screw 22, also moves towards another clamping base 12, causing the clamping base 12 to clamp the edge of the mesh frame 40 with a preset clamping force. In practical applications, the drive motor 21 can be a servo motor or a closed-loop stepper motor to achieve precise drive. Of course, the drive motor 21 can also be replaced with a hydraulic cylinder or pneumatic cylinder with a high-precision proportional valve and a position sensor to achieve stepless adjustment of the clamping force.

[0027] Similarly, when the drive motor 21 drives the lead screw 22 to rotate in the opposite direction, the nut of the lead screw 22 moves away from the other clamping base 12 (i.e., Figure 2 (In the opposite direction of the direction indicated by the dashed arrow) the clamping base 12, which is fixedly connected to the screw 22 nut, also moves away from the other clamping base 12. The clamping base 12, which is fixedly connected to the screw 22 nut, returns to the initial position to loosen the clamping on the mesh frame 40.

[0028] Furthermore, refer to Figure 2 The motor-driven clamping mechanism 20 also includes a first clamping block 24 and a guide rail 25; the first clamping block 24 is connected to the lead screw 22 nut; one end of the guide rail 25 is fixedly connected to the first clamping block 24, and the other end of the guide rail 25 is fixedly connected to the elastic pull-back clamping mechanism 30.

[0029] In practical applications, the motor-driven clamping mechanism 20 can also be associated with the elastic pull-back clamping mechanism 30. Specifically, the motor-driven clamping mechanism 20 is set at the end of the clamping base 12 on one side, and the elastic pull-back clamping mechanism 30 is set at the end of the clamping base 12 on the other side, with the motor-driven clamping mechanism 20 and the elastic pull-back clamping mechanism 30 located at the same end. The first clamping block 24 is connected to the lead screw 22 nut. When the lead screw 22 nut moves, it will drive the first clamping block 24 to move together, and clamp one end of the guide rail 25 through the first clamping block 24. When the first clamping block 24 moves, it will also drive the guide rail 25 to move together. That is to say, the lead screw 22 nut, the first clamping block 24, and the guide rail 25 move synchronously. The elastic pull-back clamping mechanism 30 is connected to the other end of the guide rail 25. When the first clamping block 24 drives the guide rail 25 to move, the elastic pull-back clamping mechanism 30 will also produce a corresponding displacement, causing the elastic element 31 to be stretched, thereby generating a pull-back force.

[0030] Furthermore, refer to Figure 2The elastic pull-back clamping mechanism 30 includes a connecting structure, a second clamping block 33, an elastic element 31, and a fixing element 34; the connecting structure is connected to the clamping base 12 on the other side; the fixing element 34 is fixedly mounted on the screen printing machine; the other end of the guide rail 25 passes through the fixing element 34 and is fixedly connected to the connecting structure through the second clamping block 33; one end of the elastic element 31 is connected to the fixing element 34, and the other end of the elastic element 31 is connected to the connecting structure.

[0031] In practical applications, the elastic pull-back clamping mechanism 30 is connected to the end of the clamping base 12 on the other side via a connecting structure. Specifically, an elastic element 31, such as a butterfly spring / compression spring, is provided above the connecting structure. One end of the compression spring is connected to the connecting structure, and the other end is connected to the fixing element 34. The fixing element 34 can be fixedly connected to the base of the screen printing machine to ensure that the fixing element 34 remains stationary during the movement of the drive motor 21. Furthermore, a second clamping block 33 is provided below the connecting structure, allowing the other end of the guide rail 25 to pass through the fixing element 34 and be fixedly connected to the second clamping block 33. When the guide rail 25 moves with the first clamping block 24, the second clamping block 33 connected to the other end of the guide rail 25 will also move in the same direction, thereby driving the connecting structure to move synchronously. At this time, the compression spring is stretched, simultaneously generating a pull-back force in the opposite direction of the stretching. This pull-back force can counteract the movement tendency of the clamping base 12 connected to the elastic pull-back clamping mechanism 30. Furthermore, the more obvious (or greater) the movement tendency brought by the drive motor 21 to the clamping base 12 connected to the elastic pull-back clamping mechanism 30, the greater the pull-back force. This ensures that the entire clamping force remains dynamically clamped, preventing deformation or loss of mesh tension in the aluminum alloy mesh frame 40 due to excessive clamping force, and also preventing displacement directly caused by insufficient clamping force. This allows the above-mentioned solution of this application to achieve "adaptive" precise force control of the mesh frame 40's specifications and process requirements. The function of the disc spring / compression spring in this embodiment can be achieved by a nitrogen spring, a polyurethane elastomer, or an air spring with adjustable preload.

[0032] In some implementations, reference Figure 1 and Figure 2 There are two motor-driven clamping mechanisms 20, which are respectively located at both ends of the clamping base 12 on one side.

[0033] In practical applications, in order to ensure the clamping effect, clamping accuracy and clamping stability of the mesh frame 40, a motor-driven clamping mechanism 20 can be set at both ends of one of the clamping bases 12. The setting method is described above, and will not be elaborated further in this embodiment.

[0034] refer to Figure 1 and Figure 2Based on this, two elastic pull-back clamping mechanisms 30 are provided, and the two elastic pull-back clamping mechanisms 30 are respectively located at both ends of the clamping base 12 on the other side; the elastic pull-back clamping mechanism 30 located at the same end of the clamping base 12 is connected to the motor-driven clamping mechanism 20.

[0035] In practical applications, to ensure that both ends of the clamping base 12 have a dynamic clamping effect, a motor-driven clamping mechanism 20 is provided at both ends of the clamping base 12 on one side, and an elastic pull-back clamping mechanism 30 is provided at both ends of the clamping base 12 on the other side. The motor-driven clamping mechanism 20 and the elastic pull-back clamping mechanism 30 located at the same end are associated. The dynamic clamping method has been described in detail in the above embodiments, and will not be repeated here.

[0036] refer to Figure 3 This embodiment provides a control method for the clamping device of the screen printing frame 40, which uses the clamping device of the screen printing frame 40 as described above to clamp and control the screen printing frame 40. The method specifically includes the following steps: Step 100: Obtain the placement signal of the wire frame 40, and trigger the clamping command according to the placement signal; Step 200: Control the electromagnetic adsorption clamping mechanism 10 to adsorb and clamp the mesh frame 40 according to the clamping command; Step 300: Determine the moving distance of the motor-driven clamping mechanism 20 according to the preset model of the wire frame 40, and control the motor-driven clamping mechanism 20 to drive the clamping base 12 on one side to move to the clamping base 12 on the other side by a certain distance. Step 400: After the clamping base 12 on one side is moved a distance by the motor-driven clamping mechanism 20 to the clamping base 12 on the other side, the elastic pull-back clamping mechanism 30, which is connected to the motor-driven clamping mechanism 20, generates a pull-back force, which pulls the clamping base 12 on the other side back to the clamping base 12 on one side.

[0037] In practical applications, the specific clamping operation process is as follows: First, the operator places the mesh frame 40 in the approximate area of ​​the clamping base 12 and triggers the "clamping" command. The control system, based on the "clamping" command, first energizes the electromagnetic adsorption clamping mechanism 10, causing the mesh frame 40 to be instantly flattened, achieving precise positioning. Then, the control system calculates the required moving distance of the drive motor 21 based on the preset mesh frame 40 model (or the frame width automatically detected by a sensor). The clamping base 12 moves this distance to the target position. With motor-driven clamping mechanisms 20 at both ends of the clamping base 12, the drive motors 21 at both ends move synchronously, causing the clamping base 12 to run a preset "spring stroke" (e.g., 0.5-2mm), stretching the spring assembly and generating a pre-tensioning force from the compression spring. The entire clamping force is controlled by the motor current threshold, ensuring precise and repeatable force.

[0038] Using the control method of this application, the clamping process is automatically completed by the controller, and the clamping force is precisely controlled by the motor current, eliminating human error and over-clamping damage, and ensuring consistency in each clamping. Furthermore, the clamping stroke and force can be adjusted via a program, eliminating the need for any manual mechanical adjustments, and it is compatible with screen frames 40 of different sizes and thicknesses, reducing plate changeover time by more than 50%, making it ideal for flexible production needs. In addition, by introducing a dynamic compensation force system formed by spring pullback, it actively counteracts the periodic external forces during the printing process, fundamentally solving the persistent problem of "micro-displacement" of the screen frame 40, and providing hardware support for achieving ultra-high precision registration.

[0039] Furthermore, control methods also include: When the scraper acts on the mesh plate along the direction from one clamping base 12 to the other clamping base 12, the pull-back force generated by the elastic pull-back clamping mechanism 30 is increased. The increased pull-back force pulls the clamping base 12 on the other side back to the clamping base 12 on one side, so as to counteract the displacement tendency generated when the scraper acts on the screen.

[0040] During the printing process, when the squeegee applies a force F_squeepee to the screen, it tends to cause a slight displacement Δx in the squeegee's moving direction. This displacement tendency causes the elastic pull-back clamping mechanism 30 on one side to be further stretched, instantly increasing the pull-back force F_spring; simultaneously, the spring pull-back force on the other side decreases accordingly, but remains greater than zero. This dynamically changing pull-back force, together with the electromagnetic adsorption force and the motor's static clamping force, forms an adaptive adjustment net, firmly locking the squeegee 40 and suppressing the displacement Δx. At the end of printing, the controller controls the drive motor 21 of the clamping mechanism 20 to rotate in the opposite direction, causing the clamping base 12 to retract to its initial open position, completely releasing the spring pull-back preload. Subsequently, the electromagnetic adsorption unit is powered off, allowing the operator to easily remove the squeegee 40.

[0041] In one feasible implementation, the motor-driven clamping mechanism 20 includes a drive motor 21, a lead screw 22, and a lead screw 22 nut. The drive motor 21 is fixedly mounted on the screen printing machine, and the drive shaft of the drive motor 21 is coaxially connected to the lead screw 22. The lead screw 22 nut is fixedly connected to a clamping base 12 on one side, and the lead screw 22 and the lead screw 22 nut cooperate with each other. Controlling the motor to drive the clamping mechanism 20 to move the clamping base 12 on one side to the clamping base 12 on the other side by a distance includes: controlling the drive motor 21 to drive the lead screw 22 to rotate in a first direction, thereby causing the lead screw 22 nut to drive the clamping base 12 on one side to move to the clamping base 12 on the other side by a distance.

[0042] Specifically, in the motor-driven clamping mechanism 20, the drive motor 21 can be fixedly connected to the base of the screen printing machine, that is, the drive motor 21 is fixedly mounted on the screen printing machine, and the output shaft of the drive motor 21 is coaxially connected to the lead screw 22. When the controller controls the output shaft of the drive motor 21 to rotate in the forward direction, the lead screw 22 also rotates in the forward direction. At the same time, the lead screw 22 nut, which cooperates with the lead screw 22, moves forward or backward along the axis of the lead screw 22 while the lead screw 22 rotates. Since the lead screw 22 nut is fixedly connected to the end of one of the clamping bases 12, when the drive motor 21 drives the lead screw 22 to rotate in the forward direction, it drives the lead screw 22 nut towards the other clamping base 12 (i.e., Figure 2 When the movement occurs (in the direction indicated by the dashed arrow), the clamping base 12, which is fixedly connected to the nut of the lead screw 22, also moves towards another clamping base 12, causing the clamping base 12 to clamp the edge of the mesh frame 40 with a preset clamping force. In practical applications, the drive motor 21 can be a servo motor or a closed-loop stepper motor to achieve precise driving.

[0043] Similarly, when the drive motor 21 drives the lead screw 22 to rotate in the opposite direction, the nut of the lead screw 22 moves away from the other clamping base 12 (i.e., Figure 2 (In the opposite direction of the direction indicated by the dashed arrow) the clamping base 12, which is fixedly connected to the screw 22 nut, also moves away from the other clamping base 12. The clamping base 12, which is fixedly connected to the screw 22 nut, returns to the initial position to loosen the clamping on the mesh frame 40.

[0044] This embodiment provides a computer-readable storage medium storing a computer program that can be executed by a processor to implement the method described above. Since the control method for the screen printing machine's frame clamping device has been described in detail in the above embodiments, it will not be repeated here.

[0045] Those skilled in the art will understand that all or part of the functions of the various methods in the above embodiments can be implemented by hardware or by computer programs. When all or part of the functions in the above embodiments are implemented by computer programs, the program can be stored in a computer-readable storage medium, which may include: read-only memory, random access memory, disk, optical disk, hard disk, etc., and the program is executed by a computer to achieve the above functions. For example, the program can be stored in the memory of a device, and when the program in the memory is executed by the processor, all or part of the above functions can be achieved. In addition, when all or part of the functions in the above embodiments are implemented by computer programs, the program can also be stored in a server, another computer, disk, optical disk, flash drive, or external hard drive, etc., and can be downloaded or copied to the memory of a local device, or the system of the local device can be updated. When the program in the memory is executed by the processor, all or part of the functions in the above embodiments can be achieved.

[0046] The above examples illustrate the present invention only to aid in understanding it and are not intended to limit the scope of the invention. Those skilled in the art can make various simple deductions, modifications, or substitutions based on the principles of this invention.

Claims

1. A screen printing machine frame clamping device, characterized in that, include: Controller, electromagnetic adsorption clamping mechanism, motor-driven clamping mechanism, and elastic pull-back clamping mechanism; The electromagnetic adsorption clamping mechanism includes two symmetrically arranged clamping bases and an electromagnetic block disposed on the clamping bases; the clamping bases are used for initial positioning of the mesh frame; the electromagnetic block is disposed on the clamping bases and is used to adsorb and fix the mesh frame after the initial positioning is completed. The motor-driven clamping mechanism is connected to the clamping base on one side of the electromagnetic adsorption clamping mechanism. The motor-driven clamping mechanism is used to drive the clamping base on one side to move to the clamping base on the other side. The elastic pull-back clamping mechanism is disposed on the clamping base on the other side of the electromagnetic adsorption clamping mechanism; the elastic pull-back clamping mechanism and the motor-driven clamping mechanism are disposed at the same end of the clamping base and are connected to the motor-driven clamping mechanism; when the motor-driven clamping mechanism drives the clamping base on one side to move to the clamping base on the other side, the elastic pull-back clamping mechanism generates a pull-back force, and the elastic pull-back clamping mechanism is used to move the clamping base on the other side to the clamping base on one side through the pull-back force; The controller is electrically connected to the electromagnetic block and the motor-driven clamping mechanism respectively. The controller is used to control the power-on of the electromagnetic block and to control the movement of the motor-driven clamping mechanism.

2. The wire mesh frame clamping device as described in claim 1, characterized in that, The motor-driven clamping mechanism includes a drive motor, a lead screw, and a lead screw nut; The drive motor is fixedly mounted on the screen printing machine, and the drive shaft of the drive motor is coaxially connected to the lead screw; the lead screw nut is fixedly connected to the clamping base on one side, and the lead screw and the lead screw nut cooperate with each other.

3. The wire mesh frame clamping device as described in claim 2, characterized in that, The motor-driven clamping mechanism further includes a first clamping block and a guide rail; the first clamping block is connected to the lead screw nut; One end of the guide rail is fixedly connected to the first clamping block, and the other end of the guide rail is fixedly connected to the elastic pull-back clamping mechanism.

4. The wire mesh frame clamping device as described in claim 3, characterized in that, The elastic pull-back clamping mechanism includes a connecting structure, a second clamping block, an elastic element, and a fixing element; The connecting structure is connected to the clamping base on the other side; The fastener is fixedly mounted on the screen printing machine; The other end of the guide rail passes through the fixing member and is fixedly connected to the connecting structure by the second clamping block; One end of the elastic element is connected to the fixing element, and the other end of the elastic element is connected to the connecting structure.

5. The wire mesh frame clamping device as described in claim 1, characterized in that, There are two motor-driven clamping mechanisms, which are respectively located at both ends of the clamping base on one side.

6. The wire mesh frame clamping device as described in claim 5, characterized in that, Two elastic pull-back clamping mechanisms are provided, and the two elastic pull-back clamping mechanisms are respectively located at both ends of the clamping base on the other side; The elastic pull-back clamping mechanism and the motor-driven clamping mechanism, located at the same end of the clamping base, are connected.

7. A control method for a screen printing machine frame clamping device, characterized in that, The wire mesh frame is clamped and controlled using the wire mesh frame clamping device as described in any one of claims 1-6, the method comprising: Obtain the placement signal of the wire frame, and trigger a clamping command based on the placement signal; The electromagnetic adsorption clamping mechanism is controlled to adsorb and clamp the wire frame according to the clamping command; The moving distance of the motor-driven clamping mechanism is determined according to the preset model of the mesh frame, and the motor-driven clamping mechanism is controlled to drive the clamping base on one side to move the moving distance to the clamping base on the other side. After the clamping base on one side of the motor-driven clamping mechanism moves the distance to the clamping base on the other side, the elastic pull-back clamping mechanism generates a pull-back force, which pulls the clamping base on the other side back to the clamping base on one side.

8. The control method as described in claim 7, characterized in that, Also includes: When the scraper acts on the mesh plate along the clamping base on one side to the clamping base on the other side, the pull-back force generated by the elastic pull-back clamping mechanism is increased. The increased pullback force pulls the clamping base on the other side back to the clamping base on one side, so as to counteract the displacement tendency generated when the scraper acts on the mesh plate.

9. The control method as described in claim 7, characterized in that, The motor-driven clamping mechanism includes a drive motor, a lead screw, and a lead screw nut. The drive motor is fixedly mounted on the screen printing machine, and the drive shaft of the drive motor is coaxially connected to the lead screw. The lead screw nut is fixedly connected to the clamping base on one side, and the lead screw and the lead screw nut cooperate with each other. The control of the motor-driven clamping mechanism to move the clamping base on one side to the clamping base on the other side by the specified distance includes: The drive motor is controlled to drive the lead screw to rotate in a first direction, thereby causing the lead screw nut to move the clamping base on one side to the clamping base on the other side by the specified distance.

10. A computer-readable storage medium, characterized in that, The medium stores a computer program that can be executed by a processor to implement the method as described in any one of claims 7-9.

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