Method for clamping a rectangular ring-shaped product and clamping tool therefor

Abstract

The application belongs to the technical field of CNC tooling fixture, and particularly relates to a clamping method of a rectangular ring product and a clamping tool thereof. The clamping method of the rectangular ring product comprises the following steps: S1, all clamping pieces are in an initial position; S2, a workpiece-to-position signal sent by an upper device is received, and all clamping pieces are driven to move towards the direction of approaching the rectangular ring product; S3, when the clamping pieces abut against the rectangular ring product, the driving of the clamping pieces is stopped; S4, when all clamping pieces abut against the rectangular ring product, all clamping pieces are driven to abut against the rectangular ring product with a preset driving force; S5, the actual abutting force between each clamping piece and the rectangular ring product is monitored in real time, an actual fluctuation value between the actual abutting force and the driving force is obtained, the size of the preset driving force is adjusted, and the actual fluctuation value is always within a preset fluctuation range; and S6, when an end signal of a CNC machine tool is received, all clamping pieces are driven to move to the initial position.

Description

Technical Field

[0001] This invention relates to the field of CNC tooling and fixture technology, and in particular to a clamping method and clamping fixture for rectangular ring-shaped products. Background Technology

[0002] Before performing CNC machining on a rectangular ring-shaped product, it is necessary to pre-clamp and fix the rectangular ring-shaped product.

[0003] Existing rectangular ring-shaped products are clamped and fixed using two sets of clamping components. Specifically, the rectangular ring-shaped product is first placed on a base with its axial direction extending vertically. One set of clamping components is placed at each end along the length direction of the rectangular ring-shaped product, and another set is placed at each end along the width direction. The two sets of clamping components clamp and fix the rectangular ring-shaped product from both ends along the length and width directions, respectively. However, the existing clamping components cannot actively adjust the clamping force on the rectangular ring-shaped product according to the actual force applied to it, and therefore cannot meet the adaptive clamping requirements for rectangular ring-shaped products.

[0004] Therefore, there is an urgent need to invent a clamping method and clamping fixture for rectangular ring-shaped products to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to provide a clamping method and clamping fixture for rectangular ring-shaped products, so as to achieve flexible clamping of rectangular ring-shaped products and improve the clamping efficiency of rectangular ring-shaped products.

[0006] To achieve this objective, the present invention adopts the following technical solution: A method for clamping a rectangular ring-shaped product, wherein the rectangular ring-shaped product is placed on a base with its axial direction extending vertically. The method for clamping the rectangular ring-shaped product involves clamping and fixing the product at both ends along its length and at both ends along its width. The method includes the following steps: S1. All of the clamping components are in the initial position; S2. Receive the workpiece arrival signal sent by the host device, and synchronously drive all the clamping parts to move towards the rectangular ring product at a preset speed. S3. When the clamping member comes into contact with the rectangular ring-shaped product, stop driving the clamping member; S4. When all the clamping members are in contact with the rectangular ring product, all the clamping members are driven to contact the rectangular ring product simultaneously with a preset driving force. S5. Monitor the actual contact force between each clamping component and the rectangular ring-shaped product in real time, and obtain the actual fluctuation value between the actual contact force and the preset driving force. If the actual fluctuation value is within the preset fluctuation range, keep the preset driving force unchanged; if the actual fluctuation value is not within the preset fluctuation range, adjust the magnitude of the preset driving force until the actual fluctuation value is within the preset fluctuation range. S6. Upon receiving the end signal from the CNC machine tool, synchronously drive all the clamping parts to move to the initial position.

[0007] As an optional solution, in S2, the preset speed is 5mm / s-15mm / s.

[0008] As an optional solution, in step S5, the absolute values ​​of the maximum and minimum values ​​of the preset fluctuation range are both 10% of the preset driving force, the maximum value of the preset fluctuation range is positive, and the minimum value of the preset fluctuation range is negative.

[0009] A clamping fixture for rectangular ring-shaped products, wherein the clamping fixture for rectangular ring-shaped products adopts the clamping method for rectangular ring-shaped products as described above, and the clamping fixture for rectangular ring-shaped products includes the base, multiple sets of clamping components and a controller; The multiple sets of clamping assemblies are divided into at least one first opposing clamping unit and at least one second opposing clamping unit. The first opposing clamping unit includes two sets of clamping assemblies arranged opposite each other along the length direction of the rectangular ring-shaped product. The second opposing clamping unit includes two sets of clamping assemblies arranged opposite each other along the width direction of the rectangular ring-shaped product. Each set of clamping assemblies includes a servo motor, a lead screw and nut structure, a force sensor, and a clamping member. The servo motor is connected to the lead screw of the lead screw and nut structure. The force sensor is connected to the clamping member and the nut in the lead screw and nut structure, respectively. The force sensor is used to detect the actual contact force between the clamping member and the rectangular ring-shaped product. The force sensor, the servo motor, the host device, and the CNC machine tool are all communicatively connected to the controller.

[0010] As an optional solution, each set of clamping components further includes: An encoder is used to detect the rotation angle of the servo motor, and the encoder is communicatively connected to the controller.

[0011] As an optional solution, the clamping element is made of polyoxymethylene material.

[0012] As an optional solution, the lead screw nut structure further includes: A guide rail is fixed on the base, the guide rail extends along the axial direction of the lead screw, and the nut is slidably engaged with the guide rail.

[0013] As an optional solution, the lead screw nut structure further includes: A coupling is fixedly connected to the output shaft of the servo motor and the lead screw, respectively.

[0014] As an optional feature, the force sensor has a range of not less than 50N; The force sensor has a detection accuracy of no more than 0.1N.

[0015] As an optional solution, stop blocks are provided at both ends of the lead screw along the axial direction, and the nut is clamped between the two stop blocks along the axial direction of the lead screw, and the stop blocks can be stopped and fixed with the nut.

[0016] The beneficial effects of this invention are: The present invention provides a method for clamping rectangular ring-shaped products. The rectangular ring-shaped product is placed on a base with its axial direction extending vertically. Clamping members located at both ends of the rectangular ring-shaped product along its length and at both ends along its width are used to clamp and fix the product. Initially, all clamping members are in their initial positions. Upon receiving a workpiece arrival signal from a host device, all clamping members are synchronously driven to move closer to the rectangular ring-shaped product. The movement stops when the clamping members come into contact with the rectangular ring-shaped product. The clamping components are driven until each component abuts against the rectangular ring-shaped product, completing the initial positioning of the product. Then, a preset driving force synchronously drives all the clamping components to abut against the rectangular ring-shaped product. This allows for clamping and fixing the rectangular ring-shaped product from both its length and width directions, enabling rapid abutment between the clamping components and the rectangular ring-shaped product even before contact, thus improving the docking efficiency. This is achieved through the process of driving the clamping components to abut against the rectangular ring-shaped product with a preset driving force. During the process, the actual contact force between each clamping component and the rectangular ring-shaped product is monitored in real time, and the actual fluctuation value between the actual contact force and the preset driving force is obtained. If the actual fluctuation value is within the preset fluctuation range, the preset driving force remains unchanged; if the actual fluctuation value is not within the preset fluctuation range, the magnitude of the preset driving force is adjusted until the actual fluctuation value is within the preset fluctuation range. This allows for proactive force compensation of the rectangular ring-shaped product based on its actual stress condition during subsequent processing, achieving flexible clamping and fixing of the rectangular ring-shaped product, solving the problem of deformation under stress, and improving the protection of the rectangular ring-shaped product. When the end signal of the CNC machine tool is received, all clamping components are synchronously driven to move to the initial position so that the clamped rectangular ring-shaped product can be released after processing is completed. From the moment the rectangular ring-shaped product is placed in the clamping position by the host device to the end of the CNC machine tool's processing of the rectangular ring-shaped product, no manual intervention is required. The fully automatic clamping operation reduces the labor intensity of workers and solves the processing risks caused by human error. In addition, the preset driving force and preset fluctuation range are adjustable, which can be designed for rectangular ring products of different materials and sizes, and has a wide range of applications. For example, the clamping parameters (such as feed speed, clamping force, holding time, etc.) of rectangular ring products of different materials and sizes can be pre-stored in the controller. When a specific product needs to be clamped and fixed, the clamping parameters can be called with one click, further improving the clamping efficiency.

[0017] The present invention also provides a clamping fixture for rectangular ring-shaped products. By applying the above-mentioned clamping method for rectangular ring-shaped products to the clamping fixture for rectangular ring-shaped products, flexible clamping and fixing of rectangular ring-shaped products can be achieved, thereby improving the clamping efficiency of rectangular ring-shaped products. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the clamping fixture for rectangular ring-shaped products provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the clamping assembly provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the structural principle of the clamping fixture for rectangular ring-shaped products provided in an embodiment of the present invention; Figure 4 This is a control flowchart of the clamping fixture for rectangular ring-shaped products provided in an embodiment of the present invention.

[0019] In the picture: 100. Clamping assembly; 110. Servo motor; 120. Lead screw and nut structure; 121. Lead screw; 122. Nut; 123. Guide rail; 130. Clamping component; 140. Force sensor; 200. Abutment; 300. Rectangular ring-shaped products. Detailed Implementation

[0020] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar components or components having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0021] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection or a detachable connection; a mechanical connection or an electrical connection; a direct connection or an indirect connection through an intermediate medium; or the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0022] In the description of this invention, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0023] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0024] This embodiment provides a clamping method for a rectangular ring-shaped product, used to clamp and fix the rectangular ring-shaped product 300, wherein, as shown... Figures 1-2 As shown, the rectangular ring-shaped product 300 is placed on the base 200 with its axial direction extending vertically. The rectangular ring-shaped product is clamped and fixed by clamping members 130 located at both ends of the rectangular ring-shaped product 300 along its length direction and at both ends of the rectangular ring-shaped product 300 along its width direction. The clamping method of the rectangular ring-shaped product includes the following steps: S1. All clamping parts 130 are in their initial positions; S2. Receive the workpiece arrival signal sent by the host device and synchronously drive all the clamping parts 130 to move towards the rectangular ring product 300 at a preset speed. S3. When the clamping member 130 comes into contact with the rectangular ring-shaped product 300, stop driving the clamping member 130. S4. When all the clamping parts 130 are in contact with the rectangular ring product 300, all the clamping parts 130 are driven to contact the rectangular ring product 300 simultaneously with a preset driving force. S5. Monitor the actual contact force between each clamping component 130 and the rectangular ring product 300 in real time, and obtain the actual fluctuation value between the actual contact force and the preset driving force. If the actual fluctuation value is within the preset fluctuation range, keep the preset driving force unchanged; if the actual fluctuation value is not within the preset fluctuation range, adjust the magnitude of the preset driving force until the actual fluctuation value is within the preset fluctuation range. S6. Upon receiving the end signal from the CNC machine tool, synchronously drive all clamping parts 130 to move to their initial positions.

[0025] The clamping method for this rectangular ring-shaped product involves placing the rectangular ring-shaped product 300 on the base 200 with its axial direction extending vertically. The rectangular ring-shaped product 300 is clamped and fixed using clamping members 130 located at both ends along its length and width. Initially, all clamping members 130 are in their initial positions. Upon receiving a workpiece arrival signal from the host device, all clamping members 130 are synchronously driven to move closer to the rectangular ring-shaped product 300. The clamping stops when the clamping members 130 come into contact with the rectangular ring-shaped product 300. The driving of the clamping members 130 is stopped until each clamping member 130 abuts against the rectangular ring-shaped product 300, completing the initial positioning of the rectangular ring-shaped product 300. Then, all the clamping members 130 are driven synchronously with a preset driving force to abut against the rectangular ring-shaped product 300. This allows the rectangular ring-shaped product 300 to be clamped and fixed from both its length and width directions. This enables rapid abutment between the clamping members 130 and the rectangular ring-shaped product 300 even before they are in contact, improving the docking efficiency of the clamping members 130 and the rectangular ring-shaped product 300. This is achieved by driving the clamping members with a preset driving force. During the contact process between clamping component 130 and rectangular ring product 300, the actual contact force between each clamping component 130 and the rectangular ring product 300 is monitored in real time, and the actual fluctuation value between the actual contact force and the preset driving force is obtained. If the actual fluctuation value is within the preset fluctuation range, the preset driving force is kept constant; if the actual fluctuation value is not within the preset fluctuation range, the magnitude of the preset driving force is adjusted until the actual fluctuation value is within the preset fluctuation range. This allows for proactive force compensation of the rectangular ring product 300 based on its actual stress condition during subsequent processing, thus achieving the desired performance of the rectangular ring product. The flexible clamping and fixing mechanism 130 solves the problem of deformation of the rectangular ring-shaped product 300 under stress, improving the protection of the rectangular ring-shaped product 300. Upon receiving the end signal from the CNC machine tool, all clamping components 130 are synchronously driven to move to the initial position, releasing the clamped rectangular ring-shaped product 300 after processing. From the moment the rectangular ring-shaped product 300 is placed in the clamping position by the host device to the completion of processing by the CNC machine tool, the entire process requires no manual intervention. The fully automated clamping operation reduces the labor intensity of workers and eliminates the processing risks caused by human error. Furthermore, the preset driving force and preset fluctuation range are adjustable, allowing for targeted design for rectangular ring-shaped products of different materials and sizes, making it widely applicable. For example, clamping parameters (such as feed rate, clamping force, and holding time) for products of different materials and specifications can be pre-stored in the controller. When a specific product needs to be clamped and fixed, the clamping parameters can be recalled with a single click, further improving clamping efficiency.

[0026] In an optional scheme S2, the preset speed is 5mm / s-15mm / s. It should be noted that in S2 of this embodiment, the preset speed is preferably 10mm / s. In other embodiments, the specific value of the preset speed can be adjusted within the range of 5mm / s-15mm / s according to actual needs; this embodiment does not impose a specific limitation.

[0027] Furthermore, in S5 of this embodiment, the absolute values ​​of both the maximum and minimum values ​​of the preset fluctuation range are 10% of the preset driving force, the maximum value of the preset fluctuation range is positive, and the minimum value of the preset fluctuation range is negative. In other embodiments, the maximum and minimum values ​​of the preset fluctuation range can also be adjusted according to actual needs; this embodiment does not impose specific limitations.

[0028] This embodiment also provides a clamping fixture for a rectangular ring-shaped product. The clamping fixture for the rectangular ring-shaped product 300 is clamped and fixed using the aforementioned clamping method. The clamping fixture includes a base 200, multiple sets of clamping assemblies 100, and a controller. The multiple sets of clamping assemblies 100 are divided into at least one set of first opposing clamping units and at least one set of second opposing clamping units. Each first opposing clamping unit includes two sets of clamping assemblies 100 arranged opposite each other along the length direction of the rectangular ring-shaped product 300. Each second opposing clamping unit includes two sets of clamping assemblies 100 arranged opposite each other along the width direction of the rectangular ring-shaped product 300. Each set of clamping assemblies 100 includes a servo motor. The system includes a motor 110, a lead screw and nut structure 120, a force sensor 140, and a clamping component 130. The servo motor 110 is connected to the lead screw 121 of the lead screw and nut structure 120. The force sensor 140 is connected to both the clamping component 130 and the nut 122 within the lead screw and nut structure 120. The force sensor 140 is used to detect the actual contact force between the clamping component 130 and the rectangular ring-shaped product 300. The force sensor 140, the servo motor 110, the host device, and the CNC machine tool are all connected to the controller. By applying the above-described clamping method for the rectangular ring-shaped product to the clamping fixture for this product, flexible clamping and fixing of the rectangular ring-shaped product 300 is achieved, improving the clamping efficiency of the rectangular ring-shaped product 300.

[0029] It should be noted that, in this embodiment, the clamping fixture for the rectangular ring-shaped product includes four sets of clamping components 100. These four sets of clamping components 100 are divided into a first opposing clamping unit and a second opposing clamping unit. The first opposing clamping unit includes two sets of clamping components 100 arranged opposite each other along the length direction of the rectangular ring-shaped product 300, and the second opposing clamping unit includes two sets of clamping components 100 arranged opposite each other along the width direction of the rectangular ring-shaped product 300. In other embodiments, the specific number of clamping components 100 can be arbitrarily adjusted within an even number of sets (four or more) according to actual needs; this embodiment does not impose a specific limitation.

[0030] Combination Figure 3 The specific structure of the clamping fixture for rectangular ring-shaped products is described below. Each clamping assembly 100 also includes an encoder, which is used to detect the rotation angle of the servo motor 110. The encoder is connected to the controller. By setting the encoder connected to the controller, the rotation angle of the servo motor 110 can be detected by the encoder, and the movement distance of the clamping component 130 can be obtained, which is convenient for subsequent data analysis.

[0031] In addition, the clamping fixture for rectangular ring-shaped products also includes a human-machine interface (HMI). The HMI is connected to the controller, allowing operators to control the start and stop of the clamping fixture via the HMI. For rectangular ring-shaped products 300 of different materials and specifications, clamping parameters (such as feed speed, clamping force, and holding time) can be pre-stored in the controller and retrieved through a window on the HMI. When a specific product needs to be clamped and fixed, the clamping parameters can be retrieved with a single click, further improving clamping efficiency.

[0032] In this embodiment, the controller is communicatively connected to the servo driver of the servo motor 110, and the controller controls the servo motor 110 by controlling the servo driver. It is understood that the controller can be a PLC motion control module or an embedded motion controller, and communicates with four servo drivers via an EtherCAT bus. The communication principles between the controller, servo drivers, human-machine interface, force sensor 140, CNC machine tool, and encoder are all existing technologies and will not be described in detail here.

[0033] Based on the clamping fixture for rectangular ring-shaped products provided in this embodiment, combined with Figure 4 In the above embodiment, the clamping member 130 is driven to abut against the rectangular ring-shaped product 300 by a preset driving force. This means that the servo motor 110 outputs a preset torque, which is converted into a preset driving force on the clamping member 130 through the lead screw and nut structure 120. When it is necessary to adjust the specific value of the preset driving force, the output torque of the servo motor 110 can be adjusted.

[0034] As an optional feature, the lead screw and nut structure 120 also includes a guide rail 123, which is fixed to the base 200 and extends axially along the lead screw 121. The nut 122 is slidably engaged with the guide rail 123. By providing the guide rail 123 extending axially along the lead screw 121, and allowing the guide rail 123 to slidably engage with the nut 122, guidance can be provided for the movement of the nut 122 along the axial direction of the lead screw 121.

[0035] In addition, the lead screw nut structure 120 also includes a coupling, which is fixedly connected to the output shaft of the servo motor 110 and the lead screw 121 respectively, so as to improve the driving stability of the servo motor 110 on the lead screw 121.

[0036] To ensure the normal use of the lead screw 121 and the nut 122, stop blocks are provided at both ends of the lead screw 121 along the axial direction. The nut 122 is clamped between the two stop blocks along the axial direction of the lead screw 121. The stop blocks can stop and fix the nut 122, so as to limit the extreme position of the nut 122 relative to the lead screw 121 along the axial direction and prevent the nut 122 from coming off the lead screw 121.

[0037] In some embodiments, the clamping member 130 is made of polyoxymethylene (POM). By using POM to make the clamping member 130, the problem of the clamping member 130 scratching the rectangular ring-shaped product 300 can be solved, thus improving the protection of the rectangular ring-shaped product 300.

[0038] In some embodiments, the force sensor 140 is a miniature strain gauge sensor, the range of the force sensor 140 is not less than 50N, and the detection accuracy of the force sensor 140 is not more than 0.1N.

[0039] In this embodiment, the rectangular ring-shaped product 300 has a size range of 100mm×80mm-105mm×85mm, is made of aluminum alloy, and has a wall thickness of 2mm. When clamping and fixing the rectangular ring-shaped product 300, the clamping force must be ≤20N to prevent deformation. In this embodiment, the servo motor 110 is a 200W AC servo motor with a brake. The encoder is a 17-bit absolute encoder. The lead screw 121 has a diameter of 12mm, a lead of 5mm, and a stroke of 50mm. The guide rail 123 has a width of 15mm and a length of 80mm. The controller uses a PLC motion control module or an embedded motion control module and communicates with the servo driver inside the servo motor 110 via an EtherCAT bus.

[0040] Combination Figure 3 and Figure 4 The specific workflow of the clamping fixture for the rectangular ring-shaped product provided in this embodiment is described below: 1) All clamping elements 130 within the four clamping assemblies 100 are in their initial positions; 2) The host device places the rectangular ring-shaped product 300 in the clamping position of the base 200, and sends the workpiece arrival signal to the controller. 3) The controller synchronously drives the clamping parts 130 in the four sets of clamping assemblies 100 to move toward the rectangular ring-shaped product 300 according to the workpiece arrival signal; 4) As the clamping member 130 moves continuously, it is determined whether the clamping member 130 is in contact with the rectangular ring product 300. The current in the servo motor 110 can be used to determine whether the clamping member 130 is in contact with the rectangular ring product 300. When the current in the servo motor 110 surges, it indicates that the clamping member 130 is in contact with the rectangular ring product 300. 5) If the clamping member 130 comes into contact with the rectangular ring-shaped product 300, stop driving the clamping member 130; 6) Determine whether all clamping members 130 are in contact with the rectangular ring-shaped product 300. If not all clamping members 130 are in contact with the rectangular ring-shaped product, keep the clamping members 130 that are in contact with the rectangular ring-shaped product 300 stationary, and let the clamping members 130 that are not in contact with the rectangular ring-shaped product 300 continue to move, and obtain the information that the clamping members 130 are in contact with the rectangular ring-shaped product 300 according to the determination method in 4) above. 7) The servo motors 110 in the four clamping components 100 synchronously output preset torque, so as to drive the four clamping parts 130 to abut against the rectangular ring product 300 with preset driving force using the lead screw and nut structure 120. 8) The controller sends a signal to the CNC machine tool. After receiving the signal from the controller, the CNC machine tool determines that the rectangular ring product 300 has been clamped and fixed, and then begins to process the rectangular ring product 300. 9) Determine whether the rectangular ring product 300 has been processed. If the processing is completed, the clamping part 130 returns to the initial position and the rectangular ring product 300 is released. If the processing is not completed, the servo motor 110 continues to output the preset torque and the CNC machine tool continues to work. 10) During the continuous output of the preset torque by the servo motor 110 in 9) above, the force sensor 140 monitors the actual contact force between the clamping member 130 and the rectangular ring product 300 in real time, and obtains the actual fluctuation value between the actual contact force and the preset driving force. If the actual fluctuation value is within the preset fluctuation range, the servo motor 110 continues to output the preset torque, thereby keeping the preset driving force on the clamping member 130 unchanged; if the actual fluctuation value is not within the preset fluctuation range, the output torque of the servo motor 110 is adjusted to change the magnitude of the preset driving force until the actual fluctuation value is within the preset fluctuation range.

[0041] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A method for clamping rectangular ring-shaped products, characterized in that, A rectangular ring-shaped product (300) is placed on a base (200) with its axial direction extending vertically. The rectangular ring-shaped product is clamped and fixed by clamping members (130) located at both ends of the rectangular ring-shaped product (300) along its length direction and at both ends of the rectangular ring-shaped product (300) along its width direction. The clamping method of the rectangular ring-shaped product includes the following steps: S1. All of the clamping members (130) are in the initial position; S2. Receive the workpiece arrival signal sent by the host device and synchronously drive all the clamping parts (130) to move towards the rectangular ring product (300) at a preset speed. S3. When the clamping member (130) abuts against the rectangular ring product (300), stop driving the clamping member (130); S4. When all the clamping members (130) abut against the rectangular ring product (300), all the clamping members (130) are driven to abut against the rectangular ring product (300) simultaneously with a preset driving force. S5. Monitor the actual contact force between each clamping member (130) and the rectangular ring product (300) in real time, and obtain the actual fluctuation value between the actual contact force and the preset driving force. If the actual fluctuation value is within the preset fluctuation range, keep the preset driving force unchanged. If the actual fluctuation value is not within the preset fluctuation range, adjust the magnitude of the preset driving force until the actual fluctuation value is within the preset fluctuation range. S6. Upon receiving the end signal from the CNC machine tool, synchronously drive all the clamping parts (130) to move to the initial position.

2. The clamping method for rectangular ring-shaped products according to claim 1, characterized in that, In S2, the preset speed is 5mm / s-15mm / s.

3. The clamping method for rectangular ring-shaped products according to claim 1, characterized in that, In step S5, the absolute values ​​of the maximum and minimum values ​​of the preset fluctuation range are both 10% of the preset driving force, the maximum value of the preset fluctuation range is positive, and the minimum value of the preset fluctuation range is negative.

4. A clamping fixture for rectangular ring-shaped products, characterized in that, The clamping fixture for the rectangular ring-shaped product adopts the clamping method for the rectangular ring-shaped product as described in any one of claims 1-3. The clamping fixture for the rectangular ring-shaped product includes the base (200), multiple sets of clamping components (100), and a controller. The multiple sets of clamping assemblies (100) are divided into at least one first opposing clamping unit and at least one second opposing clamping unit. The first opposing clamping unit includes two sets of clamping assemblies (100) arranged opposite each other along the length direction of the rectangular annular product (300). The second opposing clamping unit includes two sets of clamping assemblies (100) arranged opposite each other along the width direction of the rectangular annular product (300). Each set of clamping assemblies (100) includes a servo motor (110), a lead screw and nut structure (120), a force sensor (140), and the clamping member. (130) The servo motor (110) is connected to the lead screw (121) of the lead screw nut structure (120). The force sensor (140) is connected to the clamping member (130) and the nut (122) in the lead screw nut structure (120) respectively. The force sensor (140) is used to detect the actual contact force between the clamping member (130) and the rectangular ring product (300). The force sensor (140), the servo motor (110), the host device and the CNC machine tool are respectively connected to the controller.

5. The clamping fixture for rectangular ring-shaped products according to claim 4, characterized in that, Each of the clamping assemblies (100) further includes: An encoder is used to detect the rotation angle of the servo motor (110), and the encoder is communicatively connected to the controller.

6. The clamping fixture for rectangular ring-shaped products according to claim 4, characterized in that, The clamping element (130) is made of polyoxymethylene material.

7. The clamping fixture for rectangular ring-shaped products according to claim 4, characterized in that, The lead screw nut structure (120) also includes: The guide slide rail (123) is fixed on the base (200), the guide slide rail (123) extends along the axial direction of the lead screw (121), and the nut (122) slides in engagement with the guide slide rail (123).

8. The clamping fixture for rectangular ring-shaped products according to claim 4, characterized in that, The lead screw nut structure (120) also includes: The coupling is fixedly connected to the output shaft of the servo motor (110) and the lead screw (121).

9. The clamping fixture for rectangular ring-shaped products according to claim 4, characterized in that, The range of the force sensor (140) is not less than 50N; The detection accuracy of the force sensor (140) is no more than 0.1N.

10. The clamping fixture for rectangular ring-shaped products according to claim 4, characterized in that, The lead screw (121) is provided with stop blocks at both ends along the axial direction. The nut (122) is clamped between the two stop blocks along the axial direction of the lead screw (121). The stop blocks can be stopped and fixed with the nut (122).

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