Pasting boundary quality control method of film connecting buckle of cotton harvesting packaging film

Abstract

The invention relates to a pasting boundary quality control method for a film connecting buckle of a cotton harvesting and packaging film, which comprises the following steps of: capturing and calculating the offset of a tooth-shaped line relative to a reference tooth-shaped line in the advancing direction of the packaging film in real time by adopting an industrial camera visual feature detection method, and controlling an infrared gradienter to do follow-up offset motion according to the offset; deviation caused by uncertain stop positions of tooth-shaped lines on the packaging film due to unstable equipment operation is avoided, a red marking line is projected on the packaging film through an infrared gradienter, the red marking line serves as a datum line for pasting the thin film connecting buckle, an operator only needs to refer to the red marking line to complete pasting operation of the thin film connecting buckle, and the operation efficiency is improved. And the accuracy and the consistency of the pasting position of the film connecting buckle are ensured.

Description

Technical Field

[0001] This invention relates to the pasting operation of film connectors on cotton harvesting and baling films, specifically to a method for quality control of the pasting boundary of film connectors on cotton harvesting and baling films. Background Technology

[0002] Large-scale cotton harvesting typically utilizes integrated harvesting and baling machines. These machines require specialized baling films for baling the cotton. This method offers high harvesting efficiency, facilitates transportation of the baled cotton, and significantly improves overall economic benefits. The production of the baling film for cotton harvesters involves attaching a film connector used to seal the baling film. The connector has double-sided adhesive strips; after peeling off the release liner, the connector is attached to the baling film. The placement of the connector relative to the spacing of the serrated lines on the baling film greatly affects the sealing effect. Substandard quality can lead to the baling film bursting during transportation or foreign objects like sand and dust entering the cotton, significantly impacting subsequent processing.

[0003] With the continuous expansion of cotton planting in my country, the mechanization rate of cotton harvesting and the increasing demands for cotton quality are leading to a growing need for high-quality specialized packing films. Currently, the production process of packing films requires attaching film connectors along the serrated lines. Due to cost considerations, existing technology primarily relies on two operators manually attaching these connectors, with the placement depending on visual estimation. This makes it difficult to guarantee the accuracy of the final attachment position and the consistency of products produced on a large scale. As the requirements for the quality of packing films during cotton harvesting and the need for comprehensive information management become increasingly stringent, improving the accuracy of the manual attachment of film connectors has become an urgent engineering challenge. Summary of the Invention

[0004] This invention discloses a method for quality control of the bonding boundary of the film connecting buckle of cotton harvesting and baling film, which can significantly improve the bonding accuracy of the film connecting buckle and the overall quality of baling film production.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows: The method for quality control of the bonding boundary of the film connecting buckle of cotton harvesting and packaging film includes the following steps: Step 1): Form serrated lines on the packaging film; Step 2): Convey the entire roll of packing film in the winding direction until the toothed line of one piece of packing film reaches the visual inspection window area of ​​the industrial camera, then stop conveying. Step 3): The industrial camera takes a picture of the position of the toothed line that reached the visual inspection window area in Step 2) on the plane of the packaging film, and feeds the toothed line position picture back to the host computer system. The host computer system stores the position information of the toothed line, and the position of the toothed line here is used as the position of the reference toothed line. Step 4): Continue conveying the entire roll of packaging film in the winding direction. Stop moving when the serrated line of another piece of packaging film enters the visual inspection window area. Take an image of the position of the serrated line on the plane of the packaging film within the visual inspection window area using an industrial camera, and send the image back to the host computer system. The host computer system uses a visual feature detection method to obtain the offset ΔL of the serrated line relative to the reference serrated line in the direction of packaging film movement. The origin of the offset calculation is the position of the reference serrated line, and the positive direction is the direction of packaging film movement. Step 5): The host computer system sends the offset to the slave computer. The slave computer controls the infrared level to move in a direction perpendicular to the movement of the packing film. The offset distance of the infrared level is L+ΔL, where L is the distance of the initial position of the infrared level in the negative direction of the reference tooth line. The infrared level illuminates a red mark line on the packing film. Step 6): The operator peels off the double-sided adhesive strip from the film connector and then sticks the film connector onto the packing film, making sure that the outer edge of the short side double-sided adhesive strip on the film connector aligns with the red marking line. Step 7): After completing Step 6), the industrial camera takes a picture of the location of the film connector buckle and sends the picture back to the host computer system. The host computer system obtains the distance value between the outer edge line of the short-side double-sided adhesive film and the toothed line on the film connector buckle through visual online measurement, and judges whether the distance value is within the preset qualified deviation range. If it is, the film connector buckle is judged to be qualified; otherwise, it is judged to be unqualified.

[0006] Furthermore, in step 2), the packing film moves 750mm in the winding direction and then stops.

[0007] Furthermore, a dark yellow kraft release paper is laid under the packaging film at the location of the visual detection window area.

[0008] Furthermore, the red marking line is 300mm long and 1mm wide.

[0009] Furthermore, within the visual inspection window area, a supplementary light source is used to obliquely illuminate the plane where the packaging film is located, thereby assisting the industrial camera in capturing images.

[0010] Furthermore, the acceptable deviation is set to ±2mm.

[0011] Furthermore, in step 4), the packing film moves 750mm in the winding direction and then stops.

[0012] Furthermore, the toothed line is a dotted splicing line formed by punching. After punching, it forms intermittent punches with a width of 0.5 mm and a length of 8 mm. During the conveying process, the packaging film is stretched by the take-up roller, and the punches form an ellipse shape with a width of 1 mm. When there are more than five consecutive elliptical punches in the visual inspection window area, a regular center point line can be formed. This center point line forms an axial position deviation between the reference toothed line on the packaging film plane and the packaging film in the direction of travel. This position deviation is the offset.

[0013] Furthermore, the packing film moves at a speed of 3 meters per second.

[0014] This invention employs an industrial camera visual feature detection method to capture and calculate in real time the offset of the toothed line relative to the reference toothed line in the direction of the packing film's movement. Based on the offset, an infrared level is controlled to perform a follow-up offset movement, avoiding deviations caused by unstable equipment operation leading to inconsistent stopping positions of the toothed line on the packing film. The infrared level projects a red marking line onto the packing film, which serves as the reference line for attaching the film connector. Operators only need to refer to the red marking line to complete the attachment of the film connector, ensuring the accuracy and consistency of the film connector's attachment position. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of the film connector buckle in the embodiment; Figure 2 for Figure 1 Enlarged view of the area circled in the middle; Figure 3 A schematic diagram showing the marking lines indicating the positions where the film connectors are attached to the packaging film; Figure 4 This is a flowchart illustrating the method for controlling the bonding boundary quality of the film connector buckle in this embodiment.

[0016] Figure label: 1. Film connector buckle; 101. Long side film double-sided adhesive; 102. Long side film; 103. Short side film double-sided adhesive; 104. Short side film; 105. Short side film outer edge line; 106. Short side film double-sided adhesive outer edge line; 107. Long side film outer edge line; 108. Long side film double-sided adhesive inner edge line; 109. Fold line; 2. Serrated line; 3. Base serrated line; 4. Red marking line. Detailed Implementation

[0017] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0018] This embodiment discloses a method for quality control of the bonding boundary of the film connecting buckle of cotton harvesting and packing film. Before introducing the technical solution of the present invention, the background technology of the packing film and the film connecting buckle 1 in the prior art will be explained first, so as to fully understand the technical solution protected by the present invention.

[0019] The entire roll of packing film is divided into multiple individual sheets by a toothed line 2. During processing, the packing film is punched at intervals using a toothed line punching device to form the toothed lines 2. The toothed lines 2 can be viewed as dotted splicing lines, formed by multiple spaced punches. After the entire roll of packing film is installed on the automatic cotton harvester, during the automatic cotton harvesting and rolling process, after one roll of cotton is harvested, the harvester will break adjacent sheets of packing film apart at the toothed lines. In this embodiment, the punch width of the toothed line 2 is approximately 0.5 mm, the length is approximately 8 mm, and the two ends of the toothed line 2 are approximately 150 mm from the edge of the packing film.

[0020] During production, each sheet of packing film needs to be affixed with a film connector 1, with the connector 1 covering the serrated line 2. The structure of the film connector 1 is as follows: Figure 1 and Figure 2 As shown, the film connector 1 is a folded double-sided adhesive splicing seam connector with unequal side lengths, and its overall shape is a long rectangle. Figure 2 As shown, the membrane connector 1 is folded towards the bottom along the fold line 109, forming a width (here, width refers to...) Figure 2 Two parts with different horizontal lengths, among which, Figure 2 The film is wider at the top and narrower at the bottom when folded. For easy distinction, the wider top part is called the long side film 102, and the narrower bottom part is called the short side film 104. A double-sided adhesive tape 101, approximately 30mm wide, is attached near the outer edge 107 of the long side film. A double-sided adhesive tape 103, approximately 200mm wide, is attached to the short side film 104. The distance between the outer edge 106 and the outer edge 105 of the short side film is 6mm. A certain distance is maintained between the outer edge 105 of the folded short side film and the inner edge 108 of the long side film. When the film connector 1 with the above structure is attached to the packaging film, it is combined with… Figure 3 As shown, it is necessary to make the outer edge line 105 of the short side film coincide with the toothed line 2 as much as possible. However, since the short side film 104 is folded under the long side film 102, although the film connecting buckle 1 is a transparent film, it is difficult to visually align and stick the outer edge line 105 of the short side film with the toothed line 2, which often results in operational errors exceeding the allowable range.

[0021] Therefore, this invention proposes a method for quality control of the bonding boundary of the film connecting buckle of cotton harvesting and packaging film, such as... Figure 4 As shown, the main steps include the following: The method for quality control of the bonding boundary of the film connecting buckle of cotton harvesting and packaging film includes the following steps: Step 1): Form serrated lines 2 at intervals on the entire roll of packaging film. This step can be completed using existing technology.

[0022] Step 2): Obtain the position of the reference tooth profile 3; Specifically, the starting end of the entire roll of packing film is conveyed and moved approximately 750mm in the winding direction and then stopped. At this point, the serrated line 2 of the first packing film rests within the visual inspection window area of ​​the industrial camera, awaiting inspection. In this embodiment, a visual feature detection method based on an industrial camera is used. To improve the post-processing feature recognition of the images captured by the industrial camera, this embodiment utilizes both an industrial camera and a supplementary light source to complete the image capture. Both the industrial camera and the supplementary light source are located inside a light shield. The light shield provides impact protection for the industrial camera and reduces the influence of external light sources. Under the supplementary light source, the industrial camera forms a visual inspection window area. The visual inspection window area is defined as the area on the surface of the packing film where the serrated line 2 is located, which is captured by the industrial camera after the serrated line 2 moves below the industrial camera. The serrated line 2 is approximately located at the center of the visual inspection window area. The supplementary light source is tilted downwards, which avoids reflections on the packing film caused by vertical supplementary lighting and also improves the post-processing feature recognition of the images captured by the industrial camera. The reference toothed line 3 is the initial stage of the fixed installation of the industrial camera. The position information of the toothed line 2 on the plane of the packaging film is collected when the operator moves the packaging film 750 mm in the direction of the packaging film according to the product quality standard and stops. This position information will be used as the real-time position deviation comparison target of the toothed line 2 in the subsequent actual production process.

[0023] Step 3): Real-time capture and calculation of the offset ΔL of the toothed line 2 relative to the reference toothed line 3 in the direction of the packing film's travel; Specifically, the industrial camera captures an image of the position of the toothed line 2 on the packaging film plane in step 2) that reaches the visual inspection window area, and feeds it back to the host computer system. The host computer system stores the position of the reference toothed line. Then, the entire roll of packaging film continues to be fed 750mm in the winding direction. When the toothed line 2 of another piece of packaging film enters the visual inspection window area, the movement stops. The industrial camera captures another image of the position of the toothed line 2 on the packaging film plane that has entered the visual inspection window area, and feeds the image back to the host computer system. The host computer system obtains the offset ΔL of the toothed line 2 relative to the reference toothed line 3 in the packaging film's traveling direction based on a visual feature detection method. The origin of the offset calculation is the position of the reference toothed line 3, and the positive direction is the traveling direction of the packaging film. Therefore, the offset can be positive or negative. In this embodiment, the moving speed of the packaging film along the traveling direction is controlled at 3 meters per second.

[0024] In this embodiment, the offset is obtained using a visual feature detection method. During the conveying process, the front end of the packing film is continuously wound by the winding roller. During the winding process, the packing film is subjected to tensile force, stretching the perforation of the toothed line 2 from its original width of approximately 0.5 mm to approximately 1 mm, making the perforation elliptical, which is more conducive to visual feature detection and edge extraction by industrial cameras. When there are more than five consecutive elliptical perforations in the visual detection window area, a regular center point line can be formed. The center point line forms an axial position deviation between the reference toothed line 3 and the packing film plane in the direction of packing film travel. This position deviation is the offset.

[0025] Step 4): Project red marking lines 4 onto the packaging film; Specifically, in this embodiment, the red marker line 4 is generated by an infrared level. An infrared level can be installed below the packing film, directly opposite the industrial camera. The level is mounted on an electric sliding module that can drive its movement. The infrared level moves back and forth along the packing film's travel direction. The infrared level emits high-brightness, vertical, sheet-like infrared rays towards the packing film, projecting a red marker line 4 onto the film. The length of the red marker line 4 is perpendicular to the packing film's transport direction. In this embodiment, a dark yellow kraft release paper is laid below the packing film at the location of the visual inspection window. After laying the dark yellow kraft release paper, the color difference between the inside of the holes in the toothed line 2 captured by the industrial camera and the packing film is significant, which helps improve feature recognition. The infrared level projects a red marker line 4, approximately 300mm long and 1mm wide, onto the dark yellow kraft release paper. The operator can refer to the red marker line 4 when attaching the film connector 1.

[0026] The movement of the infrared level is controlled based on the real-time offset. The host computer system sends the acquired offset to the PLC slave computer that controls the movement of the infrared level. The PLC slave computer controls the electric slide module to drive the infrared level to move in a direction perpendicular to the movement of the packing film. The following offset distance of the infrared level is L+ΔL, where L is the initial distance of the infrared level in the negative direction of the reference toothed line 3. After receiving the offset ΔL, the PLC slave computer drives the infrared level to move a distance of L+ΔL in the direction of the reference toothed line 3. The red marking line 4 formed by the infrared level on the dark yellow kraft release paper also makes an equidistant following offset movement.

[0027] Step 5): Attach the film connector 1 to the packing film; Specifically, the operator peels off the double-sided adhesive strip from the film connector 1, and then sticks the film connector 1 onto the packing film. When sticking, the outer edge line 106 of the short side double-sided adhesive strip on the film connector 1 is aligned with the red marking line 4. At this time, the outer edge line 105 of the short side film is aligned with the toothed line 2.

[0028] Step 6): Check and judge whether the position of the pasted film connector 1 is qualified; Specifically, an industrial camera captures an image of the location of the film connector 1 and sends the image to a host computer system. The host computer system uses online vision measurement to obtain the distance between the outer edge line 106 of the short-side double-sided adhesive film and the toothed line 2 on the film connector 1, and determines whether this distance is within a preset acceptable deviation range. The acceptable deviation is the operational error caused by manual operation when the outer edge line 106 of the short-side double-sided adhesive film coincides with the red marker line 4 during pasting. This operational error is generally ±2mm. In extreme cases, the outer edge line 106 of the short-side double-sided adhesive film may not coincide with the toothed line 2. The host computer system determines whether this distance is within the acceptable deviation range. If it is within the acceptable deviation range, the pasting position of the film connector 1 is acceptable, and the packaging film continues to be conveyed for subsequent processes. If it is deemed unacceptable, an alarm signal is activated to remind the operator to paste it again. If it is unacceptable both times, the production line quality manager determines whether to scrap it.

[0029] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for quality control of the bonding boundary of the film connecting buckle of cotton harvesting and packaging film, characterized in that, Includes the following steps: Step 1): Form serrated lines on the packaging film; Step 2): Convey the entire roll of packing film in the winding direction until the toothed line of one piece of packing film reaches the visual inspection window area of ​​the industrial camera, then stop conveying. Step 3): The industrial camera takes a picture of the position of the toothed line that reached the visual inspection window area in Step 2) on the plane of the packaging film, and feeds the toothed line position picture back to the host computer system. The host computer system stores the position information of the toothed line, and the position of the toothed line here is used as the position of the reference toothed line. Step 4): Continue conveying the entire roll of packaging film in the winding direction. Stop moving when the serrated line of another piece of packaging film enters the visual inspection window area. Take an image of the position of the serrated line on the plane of the packaging film within the visual inspection window area using an industrial camera, and send the image back to the host computer system. The host computer system uses a visual feature detection method to obtain the offset ΔL of the serrated line relative to the reference serrated line in the direction of packaging film movement. The origin of the offset calculation is the position of the reference serrated line, and the positive direction is the direction of packaging film movement. Step 5): The host computer system sends the offset to the slave computer. The slave computer controls the infrared level to move in a direction perpendicular to the movement of the packing film. The offset distance of the infrared level is L+ΔL, where L is the distance of the initial position of the infrared level in the negative direction of the reference tooth line. The infrared level illuminates a red mark line on the packing film. Step 6): The operator peels off the double-sided adhesive strip from the film connector and then sticks the film connector onto the packing film, making sure that the outer edge of the short side double-sided adhesive strip on the film connector aligns with the red marking line. Step 7): After completing Step 6), the industrial camera takes a picture of the location of the film connector buckle and sends the picture back to the host computer system. The host computer system obtains the distance value between the outer edge line of the short-side double-sided adhesive film and the toothed line on the film connector buckle through visual online measurement, and judges whether the distance value is within the preset qualified deviation range. If it is, the film connector buckle is judged to be qualified; otherwise, it is judged to be unqualified.

2. The method for quality control of the bonding boundary of the film connecting buckle of the cotton harvesting and packaging film according to claim 1, characterized in that: In step 2), the packing film moves 750mm in the winding direction and then stops.

3. The method for quality control of the bonding boundary of the film connecting buckle of the cotton harvesting and packaging film according to claim 1, characterized in that: Dark yellow kraft release paper is laid under the packaging film at the location of the visual inspection window area.

4. The method for quality control of the bonding boundary of the film connecting buckle of the cotton harvesting and packaging film according to claim 1, characterized in that: The red marking line is 300mm long and 1mm wide.

5. The method for quality control of the bonding boundary of the film connecting buckle of the cotton harvesting and packaging film according to claim 1, characterized in that: Within the visual inspection window area, a supplementary light source is used to obliquely illuminate the plane where the packaging film is located, and the supplementary light source assists the industrial camera in taking pictures.

6. The method for quality control of the bonding boundary of the film connecting buckle of the cotton harvesting and packaging film according to claim 1, characterized in that: The acceptable deviation is set to ±2mm.

7. The method for quality control of the bonding boundary of the film connecting buckle of the cotton harvesting and packaging film according to claim 1, characterized in that: In step 4), the packing film moves 750mm in the winding direction and then stops.

8. The method for quality control of the bonding boundary of the film connecting buckle of the cotton harvesting and packaging film according to claim 1, characterized in that: The toothed line is a dotted splicing line formed by punching. After punching, it forms intermittent punches with a width of 0.5 mm and a length of 8 mm. During the conveying process, the packaging film is stretched by the take-up roller, and the punches form an ellipse shape with a width of 1 mm. When there are more than five consecutive elliptical punches in the visual inspection window area, a regular center point line can be formed. This center point line forms an axial position deviation between the reference toothed line on the packaging film plane and the packaging film in the direction of travel. This position deviation is the offset.

9. The method for quality control of the bonding boundary of the film connecting buckle of the cotton harvesting and packaging film according to claim 1, characterized in that: The packing film moves at a speed of 3 meters per second.

Images