Automatic precise glue injection device for sealing cover assembly and process method

Abstract

The invention provides an automatic precise glue injection device for sealing cover assembly and a process method, belongs to the field of aeronautical manufacturing aircraft assembly, is applied to a surface sealing process for mounting sealing covers on the heads of bolts, nuts and rivets at structural sealing parts, and realizes automatic mixing of a sealant and automatic glue injection of the sealing covers by developing an automatic system. The gluing amount is accurately controlled, and the assembly quality is improved. The problems of sealant injection and sealant mixing of the sealing cover can be solved, and the technical problems of sealant mixing time control and precise control of the sealant injection amount of the sealing cover are mainly solved; the problem that the hollow quality is unstable during glue injection filling is solved; the problems of wiredrawing and leakage environment cleaning influence during glue injection are solved; the problems of reducing mixing time and rubber material waste and improving rubber injection efficiency are solved.

Description

Technical Field

[0001] The invention belongs to the field of aviation manufacturing aircraft assembly, and relates to an automatic precise glue injection device and a process method for assembling a sealing cover. Background Art

[0002] The overall structure of the oil tank is connected and assembled with thousands of standard fasteners. In order to meet the sealing requirements of the oil tank, it is necessary to install a sealing cover on the head of the fastener to achieve sealing. During the glue injection construction of the sealing cover, it is necessary to first prepare the mixed sealant, and then inject the mixed sealant into the sealing cover according to the specified quality within the active period, and then install the sealant cap on the head of the fastener to achieve a large number of rivets, bolts and other fasteners. Supplementary sealing.

[0003] Since the existing sealing cover glue injection process is manually operated, the specifications and sizes of the sealing covers are various, and the glue injection amount of each specification sealing cover is different. The glue injection amount cannot be accurately controlled by manually injecting the sealant into the sealing cover; during the manual glue injection process, there is a hollow phenomenon inside the sealing cover, which affects the quality stability; at the same time, a large number of rivets or bolts need to be installed in the sealing cover, and all manual operations are labor-intensive, which affects the installation efficiency. Summary of the invention

[0004] In order to solve the above problems, the present invention proposes an automatic and precise glue injection device and process method for sealing cover assembly, which is applied to the bolts, nuts, and rivet heads of the structural sealing parts to install the sealing cover for surface sealing. By developing an automated system, the automatic mixing of the sealant and the automatic glue injection of the sealing cover are realized, so as to accurately control the amount of glue applied and improve the assembly quality. The present invention can solve the problems of the sealing cover's own glue injection and sealant mixing, mainly including solving the technical problems of controlling the mixing time of the sealant and the precise control of the amount of glue injected into the sealing cover; solving the problem of the hollow quality instability of the glue injection filling; solving the problem of the wire drawing and dripping of the glue injection affecting the environmental cleaning; solving the problem of reducing the mixing time and the waste of glue and improving the efficiency of the glue injection.

[0005] The present invention adopts the following technical solutions:

[0006] A sealing cover is assembled with an automatic precision glue injection device, the automatic precision glue injection device comprising a sealant component a glue barrel 1, a component a conveying mechanism bracket 2, a component a conveying pump 3, a component a conveying pipe 4, a flexible fast switching workbench 5, a multi-purpose robot 6, a line laser camera 7, a component a screw pump and a numerical control unit 8, a component b screw pump and a numerical control unit 9, an actuator flange 10, a spiral blade static mixing tube 11, a sealing cap grasping mechanism 12, a front workpiece clamp 13, a rear front workpiece clamp 14, a component b conveying pipe 15, a component b conveying pump 16, a component b conveying mechanism bracket 17, and a sealant component b glue barrel 18.

[0007] The sealant component a glue barrel 1 and the sealant component b glue barrel 18 are respectively filled with component a colloid and component b colloid, and the two glue barrels are respectively placed stably by the component a conveying mechanism bracket 2 and the component b conveying mechanism bracket 17 to prevent tipping over. The upper ends of the two glue barrels are respectively connected with the component a conveying pipe 4 and the component b conveying pipe 15, and the two conveying pipes are respectively provided with the component a conveying pump 3 and the component b conveying pump 16, which are used to extract the two-component colloid from the glue barrels.

[0008] The flexible fast switching workbench 5 is provided with a plurality of mounting holes arranged in a matrix, so that the positions of the mounting components can be adjusted.

[0009] The multi-purpose robot 6 is a multi-angle rotatable robotic arm, whose lower end is installed on the flexible fast switching workbench 5, and its upper end is the execution end. The end is equipped with an actuator flange 10 for installing a line laser camera 7, a spiral blade static mixing tube 11 and a sealing cap grasping mechanism 12, wherein the spiral blade static mixing tube 11 is used for mixing and injecting two-component glue, the line laser camera 7 is used to scan and image the sealing area of ​​the processed part, and the sealing cap grasping mechanism 12 completes the picking and installation of the sealing cap in a suction cup manner. It can realize 3D high-speed translation in the workspace, as well as single-degree-of-freedom rotation around the plane normal of the flexible fast switching workbench 5, thereby completing the picking and placing of the target object.

[0010] The a component screw pump and CNC unit 8 and the b component screw pump and CNC unit 9 have the same structure. The inlet ends of the two are respectively connected to the a component delivery pipe 4 and the b component delivery pipe 15, and the outlet ends of the two are connected to the spiral blade static mixing pipe 11. The a component screw pump and CNC unit 8 and the b component screw pump and CNC unit 9 have built-in screw pumps and servo motors as quantitative delivery mechanisms to deliver the two components from the sealant a component glue barrel 1 and the sealant b component glue barrel 18 to the spiral blade static mixing pipe 11. Mixing, the screw pumps in the component a screw pump and CNC unit 8 and the component b screw pump and CNC unit 9 are driven by their own servo motors. Through the multi-servo collaborative control method based on disturbance suppression, the speed ratio of the two servo motors determines the ratio of the two components, and the speed of the two servo motors is proportional to the respective glue output speeds; the two servo motors can adjust the forward / reverse rotation of their own screw pumps, and adjust the back-sucking function through reverse rotation to reversely suck back the excess components to solve the problem of residual glue at the front end of the spiral blade static mixing tube 11. A mathematical model of a high-precision dispensing valve is established to obtain the transfer function between the output glue amount and the control input. The two servo motors are controlled by the high-precision dispensing valve injection-back-sucking double closed-loop control method to ensure precise and quantitative glue injection without glue accumulation, wire drawing, dripping, etc.

[0011] Furthermore, the screw pump and numerical control unit 8 of component A and the screw pump and numerical control unit 9 of component B have the same structure and are equipped with a built-in screw pump. Specifically, the screw pump includes an internal fixed character 19 of the screw pump and an internal rotating character 20 of the screw pump. The outer contour of the internal fixed character 19 of the screw pump is wavy and surrounds the internal rotating character 20 of the screw pump. The internal rotating character 20 of the screw pump is an eccentric screw. The two are meshed to form a spiral volume chamber. The internal rotating character 20 of the screw pump is driven by a servo motor. The internal rotating character 20 of the screw pump rotates to transport the components in the volume chamber from the inlet to the outlet, and each rotation thereof corresponds to a certain flow rate.

[0012] The spiral blade static mixer 11 is provided with alternately arranged 180-degree twisted spiral blades 21 and 90-degree twisted spiral blades 22. The components a and b are respectively transported to the inlet of the spiral blade static mixer 11 by the component a screw pump and numerical control unit 8 and the component b screw pump and numerical control unit 9 in proportion. The two components are obviously mixed at the inlet and gradually tend to a uniform concentration state after being divided by the 180-degree twisted spiral blades 21 and the 90-degree twisted spiral blades 22. For adhesives with high viscosity, the mixing performance is improved by increasing the number of blades.

[0013] The front workpiece fixture 13 and the rear workpiece fixture 14 form a frame-type fixture, which is fixedly installed on the flexible fast switching workbench 5 and is used for clamping and fixing the parts to be processed.

[0014] An automatic and precise glue injection process method for sealing cover assembly is implemented based on the automatic and precise glue injection device, and the process method comprises the following steps:

[0015] Step 1: Fix and clamp the parts to be processed.

[0016] The part to be processed is clamped and fixed on the flexible rapid switching workbench 5 by the front workpiece clamp 13 and the rear front workpiece clamp 14, and the area to be sealed is exposed.

[0017] Step 2: Screw image acquisition and identification and positioning.

[0018] The multi-purpose robot 6 carries a line laser camera 7 to perform reciprocating scanning imaging within a fixed range. After preprocessing the acquired depth image, the template matching is used to find the approximate position of the screws and rivets. The screws and rivets are cropped without changing the image size. Then the local image is converted into a point cloud model, and the root area and the end area of ​​the screws and rivets are separated by density clustering; the matching rubber cap type is determined by the end quasi-circle diameter, the root quasi-circle diameter and the vertical position difference; the end center point is used, combined with the linear fitting and inclination angle of the root area, to solve the three-dimensional coordinates of the screws and rivets and the robot posture information of each point to be operated. Specifically:

[0019] (1) Pretreatment

[0020] In order to make the detection more accurate, the image is preprocessed before using template matching to find the approximate positions of the screws and rivets. This includes image enhancement and converting the image pixel type from integer to floating point. Threshold segmentation is used to divide the area to be sealed into three areas, and screws and rivets are searched separately in each area to speed up the calculation and reduce the matching error rate.

[0021] (2) Template matching

[0022] In order to find the approximate position of the screw, a template matching algorithm based on cross-correlation is used to retrieve the ROI area in the depth map of the structural part to be inspected, and it is cropped in a rectangular frame while keeping the size consistent with the original image. The principle of the template matching algorithm based on cross-correlation is as follows: a matching method based on grayscale features, using a normalized cross correlation matching (Normalized Cross Correlation, NCC) based on row vectors to measure the relationship between the template image and the detection image. Therefore, compared with the matching algorithm based on grayscale values, this method is much faster and can adapt to linear illumination changes; compared with shape-based template matching, it can be applied to templates with a large number of subtle deformation textures or retrieval on blurred detection images.

[0023] (3) Point cloud screening

[0024] The pixel values ​​of the depth maps of the cropped screws and rivets are scaled to obtain the corresponding point cloud model. The point cloud is screened using unsupervised density clustering. After the parameters are adjusted, the root rectangular area and the end area are separated, and the noise is removed to obtain the end point cloud model and the root area target model.

[0025] (4) Quasi-circle diameter, position difference and matching rubber cap type

[0026] The end point cloud model is quasi-circularized to obtain the end quasi-circular diameter r; the root area target model is quasi-circular or quasi-hexagonal to obtain the root diameter R; the target height H of the rivet or screw is estimated by calculating the vertical difference between the end z-axis center and the root z-axis center, and the rubber cap type parameters in the finite sample library are retrieved and compared with the detection value to find the matching rubber cap type.

[0027] Step 3: Pick up and install the sealing cap

[0028] A robot kinematic model is established, and trajectory planning is performed in Cartesian space and joint axis space using a modified trapezoidal acceleration law. The sealing cap grasping mechanism 12 picks up the sealing cap in a suction cup manner, and moves the sealing cap to the bottom of the spiral blade static mixing tube 11 through planar motion. The servo motors in the a component screw pump and CNC unit 8 and the b component screw pump and CNC unit 9 are operated, and the a and b component glues enter the spiral blade static mixing tube 11 in proportion and are mixed and injected into the sealing cap from the outlet of the spiral blade static mixing tube 11 to complete the glue injection process. The position of the screws of the component to be processed is determined through the visual guidance of the line laser camera 7, and the multi-purpose robot 6 is controlled to install the sealing cap to the corresponding screw end.

[0029] Beneficial effects of the present invention:

[0030] (1) The sealant can be mixed automatically to achieve ready-to-use mixing, and the mixing amount can be accurately controlled. The mixing performance technical indicators meet the material technical standards to ensure the mixing quality.

[0031] (2) Realize precise control of the amount of glue injected into the sealing cover automatically, fill it densely without hollows, and improve the injection quality and production efficiency.

[0032] (3) The sealing cover injection process is achieved without drawing or dripping, and no additional cleaning is required, keeping the environment clean. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic diagram of the structure of the automatic precision glue injection device assembled on the sealing cover.

[0034] Figure 2 It is a schematic diagram of the assembly structure of the internal fixed characters and the internal rotating characters of the screw pump.

[0035] Figure 3 This is the structural diagram of the spiral blade static mixer.

[0036] In the figure, 1-sealant component a barrel; 2-bracket of component a delivery mechanism; 3-component a delivery pump; 4-component a delivery pipe; 5-flexible quick switching workbench; 6-multi-purpose robot; 7-line laser camera; 8-component a screw pump and CNC unit; 9-component b screw pump and CNC unit; 10-actuator flange; 11-spiral blade type static mixing tube; 12-sealing cap grasping mechanism; 13-front workpiece fixture; 14-rear front workpiece fixture; 15-component b delivery pipe; 16-component b delivery pump; 17-bracket of component b delivery mechanism; 18-sealant component b barrel; 19-internal fixed letter of screw pump; 20-internal rotation letter of screw pump; 21-180 degree twisted spiral blade; 22-90 degree twisted spiral blade. DETAILED DESCRIPTION

[0037] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. The drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0038] A sealing cover assembly automatic precision glue injection device, including a sealant component a glue barrel 1, a component a conveying mechanism bracket 2, a component a conveying pump 3, a component a conveying pipe 4, a flexible fast switching workbench 5, a multi-purpose robot 6, a line laser camera 7, a component a screw pump and a numerical control unit 8, a component b screw pump and a numerical control unit 9, an actuator flange 10, a spiral blade static mixing tube 11, a sealing cap grasping mechanism 12, a front workpiece fixture 13, a rear front workpiece fixture 14, a component b conveying pipe 15, a component b conveying pump 16, a component b conveying mechanism bracket 17, and a sealant component b glue barrel 18, such as Figure 1 shown.

[0039] The sealant component a rubber barrel 1 and the sealant component b rubber barrel 18 are respectively filled with component a colloid and component b colloid, and the two rubber barrels are respectively placed stably by the component a conveying mechanism bracket 2 and the component b conveying mechanism bracket 17 to avoid tipping over. The upper ends of the two rubber barrels are respectively connected with the component a conveying pipe 4 and the component b conveying pipe 15, and the two conveying pipes are respectively provided with the component a conveying pump 3 and the component b conveying pump 16, which are used to extract the two component colloids from the rubber barrels. Among them, the component a is a low-density modified polysulfide sealant base paste, and the component b is a vulcanizing agent.

[0040] The flexible fast switching workbench 5 is provided with a plurality of mounting holes arranged in a matrix, so that the positions of the mounting components can be adjusted.

[0041] The multi-purpose robot 6 is a multi-angle rotatable robotic arm, whose lower end is installed on the flexible fast switching workbench 5, and its upper end is the execution end. The end is equipped with an actuator flange 10 for installing a line laser camera 7, a spiral blade static mixing tube 11 and a sealing cap grasping mechanism 12, wherein the spiral blade static mixing tube 11 is used for mixing and injecting two-component glue, the line laser camera 7 is used to scan and image the sealing area of ​​the processed part, and the sealing cap grasping mechanism 12 completes the picking and installation of the sealing cap in a suction cup manner. It can realize 3D high-speed translation in the workspace, as well as single-degree-of-freedom rotation around the plane normal of the flexible fast switching workbench 5, thereby completing the picking and placing of the target object.

[0042] like Figure 2As shown, the a component screw pump and CNC unit 8 and the b component screw pump and CNC unit 9 have the same structure, the inlet ends of the two are respectively connected to the a component delivery pipe 4 and the b component delivery pipe 15, and the outlet ends of the two are connected to the spiral blade static mixing pipe 11. The a component screw pump and CNC unit 8 and the b component screw pump and CNC unit 9 have built-in screw pumps and servo motors as quantitative delivery mechanisms to deliver the two components from the sealant a component glue barrel 1 and the sealant b component glue barrel 18 to the spiral blade static mixing pipe 11. During mixing, the screw pumps in the component a screw pump and CNC unit 8 and the component b screw pump and CNC unit 9 are driven by their own servo motors. Through the multi-servo collaborative control method based on disturbance suppression, the speed ratio of the two servo motors determines the ratio of the two components, and the speed of the two servo motors is proportional to the respective glue output speeds; the two servo motors can adjust the forward / reverse rotation of their respective screw pumps, and adjust the back-sucking function through reverse rotation to reversely suck back the excess components to solve the problem of residual glue at the front end of the spiral blade static mixing tube 11. A mathematical model of a high-precision dispensing valve is established to obtain the transfer function between the output glue amount and the control input. The two servo motors are controlled by the high-precision dispensing valve injection-back-sucking double closed-loop control method to ensure precise and quantitative glue injection without glue accumulation, wire drawing, dripping, etc.

[0043] The screw pump and numerical control unit 8 of component A and the screw pump and numerical control unit 9 of component B have the same structure and are equipped with a built-in screw pump. Specifically, the screw pump includes an internal fixed character 19 of the screw pump and an internal rotating character 20 of the screw pump. The outer contour of the internal fixed character 19 of the screw pump is wavy and surrounds the internal rotating character 20 of the screw pump. The internal rotating character 20 of the screw pump is an eccentric screw. The two are meshed to form a spiral volume chamber. The internal rotating character 20 of the screw pump is driven by a servo motor. The internal rotating character 20 of the screw pump rotates to transport the components in the volume chamber from the inlet to the outlet. Each rotation of the screw pump corresponds to a certain flow rate.

[0044] like Figure 3 As shown, the spiral blade type static mixer 11 is provided with alternately arranged 180 degree twisted spiral blades 21 and 90 degree twisted spiral blades 22. The a and b components are respectively transported to the inlet of the spiral blade type static mixer 11 by the a component screw pump and numerical control unit 8 and the b component screw pump and numerical control unit 9 in proportion. The two components are obviously mixed at the inlet and gradually tend to a uniform concentration state after being divided by the 180 degree twisted spiral blades 21 and the 90 degree twisted spiral blades 22. For adhesives with high viscosity, the mixing performance is improved by increasing the number of blades.

[0045] The front workpiece fixture 13 and the rear workpiece fixture 14 form a frame-type fixture, which is fixedly installed on the flexible fast switching workbench 5 and is used for clamping and fixing the parts to be processed.

[0046] An automatic and precise glue injection process method for sealing cover assembly is implemented based on the automatic and precise glue injection device, and the process method comprises the following steps:

[0047] Step 1: Fix and clamp the parts to be processed.

[0048] The part to be processed is clamped and fixed on the flexible rapid switching workbench 5 by the front workpiece clamp 13 and the rear front workpiece clamp 14, and the area to be sealed is exposed.

[0049] Step 2: Screw image acquisition and identification and positioning.

[0050] The multi-purpose robot 6 carries a line laser camera 7 to perform reciprocating scanning imaging within a fixed range. After preprocessing the acquired depth image, the template matching is used to find the approximate position of the screws and rivets. The screws and rivets are cropped without changing the image size. Then the local image is converted into a point cloud model, and the root area and the end area of ​​the screws and rivets are separated by density clustering; the matching rubber cap type is determined by the end quasi-circle diameter, the root quasi-circle diameter and the vertical position difference; the end center point is used, combined with the linear fitting and inclination angle of the root area, to solve the three-dimensional coordinates of the screws and rivets and the robot posture information of each point to be operated. Specifically:

[0051] (1) Pretreatment

[0052] In order to make the detection more accurate, the image is preprocessed before using template matching to find the approximate positions of the screws and rivets. This includes image enhancement and converting the image pixel type from integer to floating point. Threshold segmentation is used to divide the area to be sealed into three areas, and screws and rivets are searched separately in each area to speed up the calculation and reduce the matching error rate.

[0053] (2) Template matching

[0054] In order to find the approximate position of the screw, a template matching algorithm based on cross-correlation is used to retrieve the ROI area in the depth map of the structural part to be inspected, and it is cropped in a rectangular frame while keeping the size consistent with the original image. The principle of the template matching algorithm based on cross-correlation is as follows: a matching method based on grayscale features, using a normalized cross correlation matching (Normalized Cross Correlation, NCC) based on row vectors to measure the relationship between the template image and the detection image. Therefore, compared with the matching algorithm based on grayscale values, this method is much faster and can adapt to linear illumination changes; compared with shape-based template matching, it can be applied to templates with a large number of subtle deformation textures or retrieval on blurred detection images.

[0055] (3) Point cloud screening

[0056] The pixel values ​​of the depth maps of the cropped screws and rivets are scaled to obtain the corresponding point cloud model. The point cloud is screened using unsupervised density clustering. After the parameters are adjusted, the root rectangular area and the end area are separated, and the noise is removed to obtain the end point cloud model and the root area target model.

[0057] (4) Quasi-circle diameter, position difference and matching rubber cap type

[0058] The end point cloud model is quasi-circularized to obtain the end quasi-circular diameter r; the root area target model is quasi-circular or quasi-hexagonal to obtain the root diameter R; the target height H of the rivet or screw is estimated by calculating the vertical difference between the end z-axis center and the root z-axis center, and the rubber cap type parameters in the finite sample library are retrieved and compared with the detection value to find the matching rubber cap type.

[0059] Step 3: Pick up and install the sealing cap

[0060] A robot kinematic model is established, and trajectory planning is performed in Cartesian space and joint axis space using a modified trapezoidal acceleration law. The sealing cap grasping mechanism 12 picks up the sealing cap in a suction cup manner, and moves the sealing cap to the bottom of the spiral blade static mixing tube 11 through planar motion. The servo motors in the a component screw pump and CNC unit 8 and the b component screw pump and CNC unit 9 are operated, and the a and b component glues enter the spiral blade static mixing tube 11 in proportion and are mixed and injected into the sealing cap from the outlet of the spiral blade static mixing tube 11 to complete the glue injection process. The position of the screws of the component to be processed is determined through the visual guidance of the line laser camera 7, and the multi-purpose robot 6 is controlled to install the sealing cap to the corresponding screw end.

[0061] The present invention has developed an automated system for sealant mixing under multi-servo collaborative control, and high-precision dispensing valve injection-backsuction double closed-loop control, focusing on realizing sealant mixing under multi-servo collaborative control, high-precision dispensing valve injection-backsuction double closed-loop control, screw identification and positioning in complex dynamic and unstable visual scenes, and robot-based soft rubber cap picking and installation involved in automatic glue injection and installation of sealing caps. At the same time, the system uses a precise control method to meet the ratio requirements and injection volume requirements, ensure the uniformity of glue injection, avoid problems such as glue drawing and dripping, greatly improve work efficiency, and improve assembly quality.

[0062] The above-described embodiments merely express the implementation methods of the present invention, but they should not be understood as limiting the scope of the present invention. It should be pointed out that for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. An automatic precision glue injection device for sealing cover assembly, characterized in that: The automatic precision glue injection device comprises a sealant component A glue barrel (1), a component A conveying mechanism bracket (2), a component A conveying pump (3), a component A conveying pipe (4), a flexible fast switching workbench (5), a multi-purpose robot (6), a line laser camera (7), a component A screw pump and a numerical control unit (8), a component B screw pump and a numerical control unit (9), an actuator flange (10), a spiral blade type static mixing tube (11), a sealing cap grasping mechanism (12), a front workpiece fixture (13), a rear front workpiece fixture (14), a component B conveying pipe (15), a component B conveying pump (16), a component B conveying mechanism bracket (17), and a sealant component B glue barrel (18); The sealant component a glue barrel (1) and the sealant component b glue barrel (18) are respectively filled with component a colloid and component b colloid, and the upper ends of the two glue barrels are respectively connected with a component a delivery pipe (4) and a component b delivery pipe (15), and the outsides of the two delivery pipes are respectively provided with a component a delivery pump (3) and a component b delivery pump (16) for extracting the two component colloids from the glue barrels; The multi-purpose robot (6) is a multi-angle rotatable mechanical arm, the lower end of which is mounted on a flexible fast switching workbench (5), and the upper end of which is an execution end, and an execution mechanism flange (10) is mounted on the end for mounting a line laser camera (7), a spiral blade static mixer (11) and a sealing cap grabbing mechanism (12), wherein the spiral blade static mixer (11) is used for mixing and injecting two-component glue liquids, the line laser camera (7) is used for scanning and imaging the parts to be processed, and the sealing cap grabbing mechanism (12) is used for completing the picking and installation of the sealing cap; The a component screw pump and numerical control unit (8) and the b component screw pump and numerical control unit (9) have the same structure. Their inlet ends are respectively connected to the a component delivery pipe (4) and the b component delivery pipe (15), and their outlet ends are both connected to the spiral blade static mixing pipe (11). The a component screw pump and numerical control unit (8) and the b component screw pump and numerical control unit (9) have built-in screw pumps and servo motors as quantitative delivery mechanisms to deliver the two components from the sealant a component glue barrel (1) and the sealant b component glue barrel (18) to the spiral blade static mixing pipe (11) for mixing. The screw pumps in the a component screw pump and numerical control unit (8) and the b component screw pump and numerical control unit (9) are respectively driven by their own servo motors. Through a multi-servo coordinated control method based on disturbance suppression, the ratio of the two components is controlled by the speed ratio of the two servo motors, and the glue output speed is controlled by the speed of the two servo motors. The spiral blade type static mixer (11) is provided with alternately arranged spiral blades (21) twisted by 180 degrees and spiral blades (22) twisted by 90 degrees. Components a and b are respectively transported to the inlet of the spiral blade type static mixer (11) in proportion by the spiral blades (21) twisted by 180 degrees and the spiral blades (22) twisted by 90 degrees. The components a and b are respectively transported to the inlet of the spiral blade type static mixer (11) by the spiral blades (21) twisted by 180 degrees and the spiral blades (22) twisted by 90 degrees and the concentrations are uniform at the outlet. The front workpiece clamp (13) and the rear workpiece clamp (14) form a frame-type clamp, which is fixedly mounted on the flexible fast switching workbench (5) and is used for clamping and fixing the parts to be processed.

2. The automatic precision glue injection device for sealing cover assembly according to claim 1, characterized in that: The sealant component A glue barrel (1) and the sealant component B glue barrel (18) are respectively stably placed by the component A conveying mechanism bracket (2) and the component B conveying mechanism bracket (17) to avoid tipping over.

3. The automatic precision glue injection device for sealing cover assembly according to claim 1, characterized in that: The flexible fast switching workbench (5) is provided with a plurality of mounting holes arranged in a matrix.

4. The automatic precision glue injection device for sealing cover assembly according to claim 1, characterized in that: The sealing cap grabbing mechanism (12) completes the picking up and installation of the sealing cap in a suction cup manner.

5. The automatic precision glue injection device for sealing cover assembly according to claim 1, characterized in that: The servo motors in the component A screw pump and CNC unit (8) and the component B screw pump and CNC unit (9) can adjust the forward / reverse rotation of their respective screw pumps, and adjust the back-suction function by reverse rotation to avoid residual glue at the front end of the spiral blade type static mixing tube (11).

6. The automatic precision glue injection device for sealing cover assembly according to claim 1, characterized in that: The screw pumps in the component A screw pump and numerical control unit (8) and the component B screw pump and numerical control unit (9) include an internal fixed letter (19) of the screw pump and an internal rotating letter (20) of the screw pump. The outer contour of the internal fixed letter (19) of the screw pump is wavy and surrounds the internal rotating letter (20) of the screw pump. The internal rotating letter (20) of the screw pump is an eccentric screw. The two mesh with each other to form a spiral volume chamber. The internal rotating letter (20) of the screw pump is driven by a servo motor. The internal rotating letter (20) of the screw pump rotates to transport the components in the volume chamber from the inlet to the outlet.

7. The automatic precision glue injection device for sealing cover assembly according to claim 1, characterized in that: The mixing performance is improved by increasing the number of the 180-degree twisted spiral blades (21) and the 90-degree twisted spiral blades (22).

8. An automatic precision glue injection process for sealing cover assembly, implemented based on the automatic precision glue injection device according to any one of claims 1 to 9, characterized in that: The process comprises the following steps: Step 1, fix and clamp the part to be processed; The part to be processed is clamped and fixed on the flexible rapid switching workbench (5) by means of a front workpiece clamp (13) and a rear front workpiece clamp (14), and the area to be sealed is exposed; Step 2: Screw image acquisition and identification and positioning; The multi-purpose robot (6) carries a line laser camera (7) to perform reciprocating scanning imaging within a fixed range, pre-processes the collected depth image, and uses template matching to find the approximate position of the screws and rivets, cuts out the screws and rivets without changing the image size, and then converts the local image into a point cloud model, and uses density clustering to separate the root area and the end area of ​​the screws and rivets; determines the matching rubber cap type by the end quasi-circle diameter, the root quasi-circle diameter and the vertical position difference; uses the end center point, combined with the linear fitting of the root area and the tilt angle, to solve the three-dimensional spatial coordinates of the screws and rivets and the robot posture information of each point to be operated; Step 3: Pick up and install the sealing cap The modified trapezoidal acceleration law is used to perform trajectory planning in Cartesian space and joint axis space respectively, the sealing cap grasping mechanism (12) completes the picking up of the sealing cap, and moves the sealing cap to the bottom of the spiral blade static mixing tube (11), the servo motors in the a component screw pump and numerical control unit (8) and the b component screw pump and numerical control unit (9) are operated, the a and b component glue liquids enter the spiral blade static mixing tube (11) in proportion and are mixed and injected into the sealing cap from the outlet of the spiral blade static mixing tube (11), completing the glue injection process; the position of the screw of the component to be processed is determined by the visual guidance of the line laser camera (7), and the multi-purpose robot (6) is controlled to install the sealing cap on the corresponding screw end.

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