Inner buckle pressing ring preloading device of shock absorber skin bag and its position judgment control method

Abstract

The application discloses an inner buckle pressing ring preloading device for a shock absorber skin bag, which comprises a workbench (1), a material placing table (2) is arranged on the upper portion of the workbench (1), and an inner supporting mechanism (3) for fixing the skin bag is arranged in the material placing table (2); a centering mechanism (4) is arranged on the workbench (1) and located on both sides of the material placing table (2); a pressing mechanism (16) is arranged on the upper portion of the workbench (1) and located above the inner supporting mechanism (3), a cylindrical column (10) is arranged at the lower end of the pressing mechanism (16), and a sealing chuck (11) with a visual camera arranged in the bottom end is arranged at the lower end of the cylindrical column (10). The inner buckle pressing ring can be stably pressed into the skin bag from the top, and the pressing accuracy is improved.

Description

Technical Field

[0001] This invention relates to the field of shock absorber assembly equipment, specifically to a pre-assembly device for the inner buckling ring of a shock absorber bladder and its position and orientation judgment and control method. Background Technology

[0002] Air spring dampers, utilizing the nonlinear stiffness characteristics of air springs, can effectively balance comfort and handling, leading to their increasingly widespread application in the automotive industry. For example, Chinese invention patent CN116372546A discloses a bladder support ring assembly device, characterized by comprising a worktable, a positioning fixture, a ring clamping mechanism, and a vertical lifting mechanism. The positioning fixture includes a bladder support member and a positioning assembly. The upper part of the positioning assembly is tapered, and a first supporting step is located below the tapered part. The bladder support member is connected to the worktable and has a through-structure in the vertical direction. The bottom of the positioning assembly is connected to the vertical lifting mechanism and moves up and down within the through-structure of the bladder support member. The ring clamping mechanism is connected to the top surface of the worktable and located around the bladder support member. The vertical lifting mechanism is connected to the bottom surface of the worktable. In this type of device, the bladder is fixed by a ring clamping mechanism when the support ring is installed. The support ring is placed on the vertical lifting mechanism and inserted into the bladder by bottom lifting. Because the outer ring clamping mechanism clamps inward, the bladder cannot be opened well, which affects the smooth entry of the support ring, reduces the installation accuracy, and the assembly efficiency is not ideal. Summary of the Invention

[0003] The purpose of this invention is to provide a pre-installation device for the inner buckling ring of a shock absorber bladder and a method for determining and controlling its position. This invention can stably press the inner buckling ring into the bladder from the top, improving the accuracy of the pressing.

[0004] The technical solution of the present invention: a pre-installation device for the inner buckling ring of a shock absorber bladder, comprising a workbench, a material placement platform on the upper part of the workbench, an inner support mechanism for fixing the bladder inside the material placement platform; a centering mechanism located on both sides of the material placement platform on the workbench; a pressing mechanism located above the inner support mechanism on the upper part of the workbench, a cylindrical column at the lower end of the pressing mechanism, a sealing clip with a vision camera built into the bottom end at the lower end of the cylindrical column, and an annular groove for placing the inner support ring on the circumferential surface of the sealing clip;

[0005] The bladder is placed on the material placement platform. The inner support mechanism clamps and positions the bottom of the bladder, while the centering mechanisms on both sides support it. The inner support ring is then placed onto the groove of the sealing clip. The pressing mechanism is activated, driving the sealing clip at the lower end of the cylindrical column into the bladder. Simultaneously, gas is injected into the bladder, causing it to inflate and expand. Once the inner support ring reaches the installation position, the sealing clip retracts, and the inner support ring is installed in the designated position. Through the coordinated operation of the positioning and installation components, the inner support ring is pressed into the bladder. By firmly fixing the bottom of the bladder and inflating it, the sealing clip is pressed in from the top, improving the installation accuracy of the inner support ring.

[0006] In the aforementioned pre-installation equipment for the inner buckling ring of the shock absorber bladder, the material placement platform consists of a base platform and an upper platform, with a positioning seat provided inside the base platform.

[0007] In the aforementioned pre-installation equipment for the inner buckling ring of the shock absorber bladder, the inner support mechanism includes a lifting cylinder bracket located at the bottom of the workbench, a lifting cylinder mounted on the lifting cylinder bracket, an inflation channel connected to an air pipe on the side of the material placement platform, and a lifting column at the extended end of the lifting cylinder; an inner support block is slidably mounted around the upper end of the positioning seat, an arc-shaped block accommodated in the upper platform is mounted on the inner support block, a positioning plate is mounted on the side of the positioning seat, and the positioning plate is elastically connected to the inner support block; the lifting column cooperates with the inner end of the inner support block.

[0008] In the aforementioned pre-installation equipment for the inner buckling ring of the shock absorber bladder, the centering mechanism includes a centering bracket set on the workbench, a centering cylinder on the centering bracket, a block support seat on the centering bracket, an intermediate block passing through the block support seat at the extended end of the centering cylinder, and a circumferential block that contacts the air bladder at the intermediate end.

[0009] In the aforementioned pre-installation equipment for the inner buckling ring of the shock absorber bladder, the pressing mechanism includes a top bracket fixed to the upper end of the workbench, a pressing cylinder is provided on the top bracket, an intermediate platform is provided at the extended end of the pressing cylinder, a connecting column is provided at the lower part of the intermediate platform, and a positioning platform composed of multiple plates is provided at the lower part of the connecting column; the cylindrical column is located at the middle of the bottom end of the positioning platform.

[0010] In the aforementioned pre-installation equipment for the inner buckling ring of the shock absorber bladder, the centering mechanisms on both sides are arranged in a horizontally staggered manner.

[0011] The specific steps in the aforementioned method for determining and controlling the position of the inner buckling ring pre-installation device of the shock absorber bladder are as follows:

[0012] Step 1: Use the vision camera at the bottom of the sealing head to take pictures of the position of the inner support ring installed inside the bladder, collect a number of standard inner support ring and inclined inner support ring images, and preprocess the images;

[0013] Step 2: Label the preprocessed images, and then divide the labeled dataset into training and validation sets;

[0014] Step 3: Feed the training set into the deep learning network for pre-training to obtain pre-training weights. Then, use these weights to feed the training set into the deep learning network again for training. Statistically measure the accuracy of the validation set under different thresholds using the trained deep learning network. Set the inner loops below the threshold as unqualified inner loops, and the others as qualified inner loops. Test to find the most suitable threshold at the highest accuracy.

[0015] Step 4: After training is complete, the real-time acquired images are input into the deep learning network. The most suitable threshold obtained in Step 3 is used to judge the inner support rings. Those below the threshold are unqualified in the initial inspection, and those below are qualified inner support rings.

[0016] In the aforementioned control method for the pre-installation device of the inner buckling ring of the shock absorber bladder, in step 1, the image preprocessing includes image filtering, image grayscale conversion, and image enhancement.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] 1. In this invention, the bladder is placed on the material placement platform, the inner support mechanism clamps and positions the bottom of the bladder, the centering mechanisms on both sides of the bladder support the bladder, the inner support ring is fitted onto the annular groove of the sealing clip, the pressing mechanism is activated, driving the sealing clip at the lower end of the cylindrical column into the bladder, and at the same time, gas is injected into the bladder to inflate and expand it. When the inner support ring reaches the installation position, the sealing clip retracts, and the inner support ring is installed in the designated position. Through the coordinated operation of the positioning component and the installation component, the inner support ring can be pressed into the bladder. By firmly fixing the bottom of the bladder and inflating it, the sealing clip is pressed in from the top, improving the installation accuracy of the inner support ring.

[0019] 2. The internal support mechanism uses a lifting column to push the surrounding internal support blocks, which in turn drive the arc-shaped expansion through the end of the bladder to clamp and fix it. The structure is simple, the operation is convenient, and the clamping is stable.

[0020] 3. The image quality is improved by filtering, grayscale conversion, and image enhancement of the obtained inner support ring image, which makes it easier to determine the position information of the inner support ring. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of the present invention;

[0022] Figure 2 This is a schematic diagram of the downward-pressing cylinder;

[0023] Figure 3 This is a schematic diagram of a material placement platform;

[0024] Figure 4 This is a schematic diagram of the positioning seat;

[0025] Figure 5 This is a schematic diagram of the internal support block;

[0026] Figure 6 This is a schematic diagram of the intermediary organization.

[0027] Figure 7 This is a schematic diagram of a sealing clip;

[0028] Figure 8 This is a flowchart illustrating the pose detection process.

[0029] Figure 9 This is a schematic diagram of image edge detection;

[0030] Figure 10 A flowchart for image feature extraction;

[0031] Figure 11 This is a schematic diagram of the image training process.

[0032] The markings in the attached diagram are as follows: 1-Workbench, 2-Material placement platform, 3-Internal support mechanism, 4-Centering mechanism, 5-Top support, 6-Pressing cylinder, 7-Intermediate platform, 8-Connecting column, 9-Positioning platform, 10-Cylindrical column, 11-Sealing clip, 12-Annular groove, 13-Bottom platform, 14-Upper platform, 15-Positioning seat, 16-Pressing mechanism, 301-Lifting cylinder support, 302-Lifting cylinder, 303-Inflation channel, 304-Lifting column, 305-Internal support block, 306-Arc-shaped block, 307-Positioning piece, 401-Centering support, 402-Centering cylinder, 403-Block support seat, 404-Intermediate block, 405-Encircling block. Detailed Implementation

[0033] The present invention will be further described below with reference to the accompanying drawings and embodiments, but this should not be construed as limiting the present invention.

[0034] Example: Pre-installation equipment for the inner buckling ring of a shock absorber bladder, including a workbench 1, with a material placement platform 2 on the upper part of the workbench 1, as shown in the attached figure. Figure 1 As shown, the material placement platform 2 is equipped with an internal support mechanism 3 for fixing the bladder; the workbench 1 has a centering mechanism 4 located on both sides of the material placement platform 2; the workbench 1 is equipped with a top support 5, and the top support 5 is equipped with a downward pressing cylinder 6, as shown in the attached diagram. Figure 2As shown, the extended end of the downward-pressing cylinder 6 is provided with an intermediate platform 7, the lower part of the intermediate platform 7 is provided with a connecting column 8, the lower part of the connecting column 8 is provided with a positioning platform 9 composed of multiple plates, the lower end of the positioning platform 9 is provided with a cylindrical column 10, the lower end of the cylindrical column 10 is provided with a sealing clip 11 with a vision camera built into its bottom end, and the circumferential surface of the sealing clip 11 is provided with an annular groove 12 for placing an inner support ring, as shown in the attached figure. Figure 7 As shown, the inner support ring is manually placed on the ring groove, which is mainly formed by cylindrical structures with different diameters on the upper and lower sides. The diameter of the upper cylinder is larger than that of the lower cylinder, forming a stepped structure. When the sealing head with the inner support ring enters the bladder, the inner support ring will come into contact with and rub against the inside of the bladder, pushing the inner support ring upward. However, due to the existence of this stepped structure, the inner support ring is blocked by the stepped ring groove, and the inner support ring is stable in the ring groove. After reaching the installation position of the inner support ring in the bladder, the sealing head retracts, and the lower end of the inner support ring is not obstructed, so it can fall into the installation position. The bladder has an installation groove for the inner support ring.

[0035] The material placement platform 2 consists of a base platform 13 and an upper platform 14, as shown in the attached figure. Figure 3 As shown, a positioning seat 15 is provided inside the base platform 13. The internal support mechanism 3 includes a lifting cylinder bracket 301 located at the bottom of the workbench 1, a lifting cylinder 302 mounted on the lifting cylinder bracket 301, and an inflation channel 303 connected to an air pipe on the side of the material placement platform 2. When the bladder needs to be inflated, air is inflated into the bladder through the inflation channel. A lifting column 304 is provided at the extended end of the lifting cylinder 302. An internal support block 305 is slidably provided around the upper end of the positioning seat 15. An arc-shaped block 306 is provided on the inner support block 305 and accommodated in the upper platform 14. A positioning piece 307 is provided on the side of the positioning seat 15, as shown in the attached figure. Figure 4 and 5 As shown, the positioning piece 307 and the inner support block 305 are elastically connected; the lifting column 304 cooperates with the inner end of the inner support block 305. The inner support mechanism pushes the surrounding inner support blocks through the lifting column, and the inner support blocks drive the arc-shaped expansion through the end of the bladder to clamp and fix it. The structure is simple, the operation is convenient, and the clamping is stable.

[0036] The centering mechanism 4 includes a centering bracket 401 mounted on the workbench 1, as shown in the attached figure. Figure 6 As shown, a centering cylinder 402 is provided on the centering bracket 401, and a block support seat 403 is also provided on the centering bracket 401. The extended end of the centering cylinder 402 is provided with an intermediate block 404 that passes through the block support seat 403. The end of the intermediate block 404 is provided with a circumferential block 405 that contacts the airbag. The centering cylinder drives the circumferential block to surround the main bladder and provide support for the bladder. The centering mechanisms 4 on both sides are arranged in a horizontally staggered manner. By setting them at different heights in the height direction, a better support effect is achieved for the bladder.

[0037] The specific steps for determining and controlling the position of the inner buckling ring pre-installed equipment of the shock absorber bladder are as follows:

[0038] Step 1: Use the vision camera at the bottom of the sealing head to photograph the position of the inner support ring installed inside the bladder, acquiring a number of images of the standard inner support ring and the inclined inner support ring, and preprocess the images. A schematic diagram of the entire process is attached. Figure 8 As shown;

[0039] In step 1, image preprocessing includes image filtering, image grayscale conversion, and image enhancement. Bilateral filtering is used during image filtering, primarily through the following formula:

[0040]

[0041] In the formula, g(x,y) is the filtered image, ω s (i,j) represents the spatial domain weights, ω r (i,j) represents the grayscale weights, ω P Let I(i,j) be the normalization parameter, I(i,j) be the noisy image, and Ω be the neighborhood range at pixel (x,y). The spatial domain weights, gray-level domain weights, and normalization parameters are represented by the following formulas:

[0042]

[0043]

[0044]

[0045] When converting an image to grayscale, the weighted average method calculates a weighted average of the three components according to their importance. The formula is as follows:

[0046] Gray = ω1R + ω2G + ω3B;

[0047] In the formula, R, G, B represent the three primary colors, and ω1, ω2, ω3 represent the weighting coefficients.

[0048] Image enhancement mainly includes image edge detection and image feature extraction. Image edge detection primarily uses the Sobel operator, employing a 3x3 convolution kernel to perform convolution operations on the grayscale image for edge detection. The convolution kernel template is attached. Figure 9 As shown, for any point P0 in this image, edge detection in the horizontal and vertical directions is performed using the two convolution kernels shown respectively:

[0049] G x (P0)=(P3+2P5+P8)-(P1+2P4+P6)

[0050] G y(P0)=(P6+2P7+P8)-(P1+2P2+P3);

[0051] G x (P0) and G y (P0) represents the horizontal and vertical edge response intensities at point P0, with values ​​indicating the likelihood that the point is an image edge. During feature extraction, starting from the top right corner of the image, all pixels are traversed from left to right and top to bottom, as shown in the attached diagram. Figure 10 As shown, g(x,y) is the gradient value of the edge detection image, T is the gradient threshold, and L is the lane width. When the gradient g(x,y) of a certain point is greater than the threshold T, and the gradient value of the pixel point g(x+L,y) at a horizontal distance L is also greater than the threshold T, then this is a possible inner ring edge point. The pixel values ​​between these two points are all set to 255, and the pixel values ​​of pixels that do not meet the conditions are set to 0.

[0052] Step 2: Label the preprocessed images, and then divide the labeled dataset into a training set and a validation set in a 1:1 ratio;

[0053] Step 3: Feed the training set into the deep learning network for pre-training to obtain pre-training weights. Then, use these weights to feed the training set into the deep learning network again for training. Statistically measure the accuracy of the validation set under different thresholds using the trained deep learning network. Set the inner loops below the threshold as unqualified inner loops, and the others as qualified inner loops. Test to find the most suitable threshold at the highest accuracy.

[0054] Step 4: After training, the real-time acquired images are input into the deep learning network. Based on the most suitable threshold obtained in Step 3, the images are judged. Those below the threshold are considered initially unqualified inner support rings; otherwise, they are considered qualified inner support rings. The deep learning network used is the YOLOv7 network, employing the Wiou loss function. Assume the anchor box is B = [x, y, w, h] and the target box is B... gt =[x gt ,y gt ,w gt ,h gt The formula for calculating wiou is as follows:

[0055]

[0056]

[0057]

[0058]

[0059] L wIoUv1 =R wIoUL IoU

[0060]

[0061] Among them, W i H i W represents the size of the overlapping portion of the two boxes. g H g Let be the size of the minimum bounding box, α be the weighting coefficient, and v be the similarity calculation for the aspect ratio of the two boxes. x, y, w, and h are the x and y coordinates of the center point of the anchor box, and the width and height of the anchor box, respectively. gt y gt w gt h gt W represents the x and y coordinates of the center point of the prediction box, the width and height of the anchor box, respectively. g H g The minimum bounding box size is indicated by the superscript *. g H g Separating it from the computation graph and turning it from a variable into a constant can prevent R from being... WIoU This generates a gradient that hinders convergence. CIoU L represents the loss of CIoU. IoU L represents the loss of IoU. WIoUv1 R represents the loss of WIoU. WIoU This represents the amplification factor for the IoU loss of a standard anchor frame. The entire process is shown in the attached figure. Figure 11 As shown.

[0062] Based on deep learning networks, image training is optimized to improve image comparison efficiency, which helps to better determine whether the inner support ring meets the installation requirements and improves detection efficiency.

[0063] The working principle of this invention is as follows: The bladder is placed on the material placement platform. The inner support mechanism clamps and positions the bottom of the bladder. The centering mechanisms on both sides of the bladder support it. The inner support ring is placed on the annular groove of the sealing clip. The pressing cylinder is activated, which drives the sealing clip at the lower end of the cylindrical column into the bladder. At the same time, gas is injected into the bladder, causing it to inflate and expand. When the inner support ring reaches the installation position, the sealing clip retracts, and the inner support ring is installed in the designated position. Through the coordinated operation of the positioning and installation components, the inner support ring can be pressed into the bladder. By firmly fixing the bottom of the bladder and inflating it, the installation accuracy of the inner support ring is improved through the pressing of the sealing clip.

[0064] The above embodiments merely illustrate implementation methods of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. Furthermore, in these embodiments, "up," "down," "left," "right," "front," and "back" represent relative positions only, not absolute positions. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A device for pre-installing the inner buckling ring of a shock absorber bladder, comprising a workbench (1), characterized in that: The workbench (1) is provided with a material placement platform (2) on the upper part, and an inner support mechanism (3) for fixing the bladder is provided inside the material placement platform (2); the workbench (1) is provided with a centering mechanism (4) on both sides of the material placement platform (2); a pressing mechanism (16) is provided above the workbench (1) and located above the inner support mechanism (3); a cylindrical column (10) is provided at the lower end of the pressing mechanism (16); a sealing clip (11) with a vision camera built into the bottom end is provided at the lower end of the cylindrical column (10); and a ring groove (12) for placing the inner support ring is provided on the circumferential surface of the sealing clip (11). Place the bladder on the material placement platform (2), the inner support mechanism (3) clamps and positions the bottom of the bladder, the centering mechanism (4) on both sides of the bladder supports the bladder, the inner support ring is put into the ring groove (12) of the sealing clip (11), the pressing mechanism (16) is started, driving the sealing clip (11) at the lower end of the cylindrical column (10) into the bladder, and at the same time, gas is filled into the bladder to make the bladder bulge and expand. When the inner support ring reaches the installation position, the sealing clip (11) retracts and the inner support ring is installed in the designated position; press the inner support ring into the bladder, stabilize and fix the bottom of the bladder, and inflate and expand it. Press it in from the top through the sealing clip to improve the installation accuracy of the inner support ring; The material placement platform (2) consists of a base platform (13) and an upper platform (14). The base platform (13) is provided with a positioning seat (15). The internal support mechanism (3) includes a lifting cylinder bracket (301) located at the bottom of the workbench (1). The lifting cylinder bracket (301) is provided with a lifting cylinder (302). The side of the material placement platform (2) is provided with an inflation channel (303) connected to an air pipe. The extended end of the lifting cylinder (302) is provided with a lifting column (304). The upper end of the positioning seat (15) is provided with an internal support block (305) that slides around it. Above the internal support block (305) is an arc-shaped block (306) that is accommodated in the upper platform (14). The positioning seat (15) is provided with a positioning piece (307) on its side. The positioning piece (307) and the inner support block (305) are elastically connected. The lifting column (304) is engaged with the inner end of the inner support block (305). The centering mechanism (4) includes a centering bracket (401) set on the workbench (1). The centering bracket (401) is provided with a centering cylinder (402). The centering bracket (401) is also provided with a block support seat (403). The extended end of the centering cylinder (402) is provided with an intermediate block (404) that passes through the block support seat (403). The end of the intermediate block (404) is provided with a circumferential block (405) that contacts the airbag.

2. The pre-installation device for the inner buckling ring of the shock absorber bladder according to claim 1, characterized in that: The pressing mechanism (16) includes a top bracket (5) fixed on the upper end of the workbench (1), a pressing cylinder (6) is provided on the top bracket (5), an intermediate platform (7) is provided at the extended end of the pressing cylinder (6), a connecting column (8) is provided at the lower part of the intermediate platform (7), and a positioning platform (9) composed of multiple plates is provided at the lower part of the connecting column (8); the cylindrical column (10) is located at the middle of the bottom end of the positioning platform (9).

3. The pre-installation device for the inner buckling ring of the shock absorber bladder according to claim 1, characterized in that: The centering mechanisms (4) on both sides are arranged in a horizontally staggered manner.

4. A control method for implementing the pre-installation device of the inner buckling ring of the shock absorber bladder according to any one of claims 1 to 3, characterized in that: The specific steps are as follows: Step 1: Use the vision camera at the bottom of the sealing head to take pictures of the position of the inner support ring installed inside the bladder, collect a number of standard inner support ring and inclined inner support ring images, and preprocess the images; Step 2: Label the preprocessed images, and then divide the labeled dataset into training and validation sets; Step 3: Feed the training set into the deep learning network for pre-training to obtain pre-training weights. Then, use these weights to feed the training set into the deep learning network again for training. Statistically measure the accuracy of the validation set under different thresholds using the trained deep learning network. Set the inner loops below the threshold as unqualified inner loops, and the others as qualified inner loops. Test to find the most suitable threshold at the highest accuracy. Step 4: After training is complete, the real-time acquired images are input into the deep learning network. The most suitable threshold obtained in Step 3 is used to judge the inner support rings. Those below the threshold are unqualified in the initial inspection, and those below are qualified inner support rings.

5. The control method for the pre-installation device of the inner buckling ring of the shock absorber bladder according to claim 4, characterized in that: In step 1, image preprocessing includes image filtering, image grayscale conversion, and image enhancement.

Images