Detection system and detection method for detecting package squareness based on flexible pressure

Abstract

The invention belongs to the technical field of package detection, and relates to a detection system and a detection method for detecting package squareness based on flexible pressure. The system comprises a detection platform, a flexible pressure acquisition unit and a data acquisition and processing unit, wherein the detection platform is used for extruding and clamping a cuboid-shaped to-be-detected sample relative to an outer vertical surface through a pressure flat plate; the flexible pressure acquisition unit is used for detecting pressure distribution of a pressed surface of the to-be-detected sample; the data acquisition and processing unit is used for acquiring, calculating and analyzing pressure distribution data so as to judge a squareness characteristic; a pressure sensor of the flexible pressure acquisition unit is arranged on the outer side surface, facing the to-be-detected sample, of a pressure flat plate of the detection platform, and the flexible pressure acquisition unit is electrically connected to the data acquisition and processing unit; the invention provides an accurate, efficient, convenient and stable solution for package squareness detection.

Description

Technical Field

[0001] This invention belongs to the field of packaging inspection technology, specifically relating to a detection system and method for detecting the squareness of packaging based on flexible pressure. Background Technology

[0002] Product packaging squareness, as a key indicator of product packaging quality, plays a vital role in protecting products, improving efficiency, and strengthening brand image. Packaging squareness can protect product integrity, improve production and logistics efficiency, enhance brand professionalism, and reduce costs. In short, while packaging squareness may seem like a detail, it is a crucial element in assessing production process control, equipment performance assurance, and operational status.

[0003] However, existing research on pre-packaged goods mainly focuses on the safety and suitability testing of packaging materials, printed image recognition, intelligent inspection by detectors, and improvements to packaging equipment, while research on the squareness characteristics of packaging is relatively limited. Current methods for detecting the squareness characteristics of packaging typically involve visual inspection, contact measurement, and non-contact detection based on computer vision.

[0004] Visual inspection involves directly observing whether the packaging is square. This method is very rough, not very accurate, and easily affected by visual factors such as the color of the trademark on the packaging, resulting in significant subjective differences.

[0005] Contact measurement methods use tools such as vernier calipers to directly contact the edge of the packaging to measure dimensions. These methods are prone to squeezing and deforming the packaging itself during the measurement process, which can lead to deviations in the measurement results and affect the measurement accuracy.

[0006] Non-contact inspection using computer vision acquires images or 3D point cloud data of packaging using industrial cameras and 3D measurement technology, and then calculates its squareness through algorithm analysis. While this method solves the problem of packaging deformation caused by contact measurement, its detection accuracy is affected by various factors such as shooting angle, equipment calibration, and the complexity of image processing algorithms. In addition, some early non-contact image acquisition devices, lacking a leveling system, may have their own horizontal state affecting the final inspection results.

[0007] Therefore, a detection device or method that can accurately quantify the squareness characteristics of packaging is needed to solve the above-mentioned technical problems. Summary of the Invention

[0008] This invention provides the following technical solution: a detection system for the squareness of packaging based on flexible pressure detection, comprising: The testing platform is used to press and clamp the rectangular sample to be tested against its two large, opposite outer surfaces in a horizontal direction using a pressure plate.

[0009] The flexible pressure acquisition unit is used to detect the pressure distribution on the pressure surface of the sample under test when it is subjected to pressure from two opposing directions.

[0010] The data acquisition and processing unit is used to acquire, calculate, and analyze the pressure distribution data detected by the flexible pressure acquisition unit, thereby determining the squareness characteristics of the sample to be tested.

[0011] The pressure sensor of the flexible pressure acquisition unit is located on the outer side of the pressure plate of the detection platform facing the sample to be tested, and the flexible pressure acquisition unit is electrically connected to the data acquisition and processing unit.

[0012] Preferably, the detection platform includes: a stage, a left detection pressure plate, and a right detection pressure plate. The left and right detection pressure plates are slidably connected to the upper surface of the stage, and the left and right detection pressure plates are arranged facing each other. When the left and right detection pressure plates slide towards each other, the left and right detection pressure plates are respectively attached to the two opposite outer surfaces of the sample to be tested.

[0013] More preferably, a center positioning line is provided in the middle of the upper surface of the stage; the left detection pressure plate and the right detection pressure plate are controlled to slide through a centering linkage mechanism.

[0014] More preferably, the flexible pressure acquisition unit includes: a pressure sensor, a distance sensor, a pressure sensor fixing slot, and a distance sensor fixing slot. The pressure sensor and the distance sensor are disposed on the vertical surfaces of the left and right detection pressure plates that are attached to the sample to be tested. The pressure sensor is disposed in the pressure sensor fixing slot, and the distance sensor is disposed in the distance sensor fixing slot.

[0015] More preferably, the pressure sensing fixing groove is cylindrical, square, or elliptical, with its central axis perpendicular to the vertical surface of each pressure plate, and the pressure sensing fixing grooves are evenly distributed in an array on the vertical surface of each pressure plate; the ranging sensing fixing groove is located at the lower middle position of the left and right detection pressure plates.

[0016] Even better, when the pressure sensing mounting groove is cylindrical, the cylindrical surfaces of two adjacent pressure sensing mounting grooves are externally tangent to each other.

[0017] This invention also discloses a method for detecting the squareness of packaging based on flexible pressure. This method employs the aforementioned detection system and includes the following steps: Step 1: Turn on the power to the testing platform, flexible pressure acquisition unit, data acquisition and processing unit, and host computer to ensure the power supply to the testing organization is connected. The flexible pressure acquisition unit and data acquisition and processing unit will enter the testing state. Place the sample to be tested on the center positioning line of the stage.

[0018] Step 2: The left and right detection pressure plates are driven to move towards each other and make contact with the sample to be tested by the centering linkage mechanism. The flexible pressure acquisition unit collects the contact surface pressure value in real time. The contact surface pressure value gradually increases as the distance between the left and right detection pressure plates decreases.

[0019] Step 3: The data acquisition and processing unit judges the pressure data. When the real-time acquired pressure value is greater than or equal to the limit pressure, the control of the left and right detection pressure plate translation drive motors stops.

[0020] Step 4: After the motor stops for a unit of time, the motor restarts and controls the left and right detection pressure plates to move a small distance toward the sample to be tested and then stop, and collects the pressure data of each pressure sensor.

[0021] Step 5: The data acquisition and processing unit calculates the pressure distribution data.

[0022] Step 6: The data acquisition and processing unit evaluates the packaging squareness of the sample by the pressure ratio of the left and right detection pressure plates. The closer the ratio is to 1, the better the packaging squareness; the further the ratio deviates from 1, the worse the packaging squareness.

[0023] Preferably, in step 4, the unit time is 1 to 5 seconds and the distance is 0.5 to 2.5 mm.

[0024] Preferably, in step 3, the pressure data determination formula for stopping the drive motors of the left and right detection pressure plates is as follows: (1) (2) in, This indicates the maximum pressure value collected by the pressure detection plate, in Pa. This represents the pressure value collected in the i-th row and j-th column of the pressure detection plate, in Pa. m and n are the row and column numbers of the pressure sensor, respectively, and i and j are the i-th row and j-th column of the pressure sensor, respectively. This indicates the limit pressure at which the pressure detection plate stops moving, expressed in Pa.

[0025] Preferably, in step 5, the formula for calculating the pressure distribution data is: Average pressure of the left detection pressure plate for: (3) The average pressure of the right detection pressure plate for: (4) In the formula, The pressure values ​​collected by the sensors in the i-th row and j-th column of the left detection pressure plate are the pressure values ​​obtained by the sensors. Let be the pressure value collected by the sensor in the i-th row and j-th column of the right detection pressure plate, i=1,…,m; j=1,…,n.

[0026] In step 6, the formula for calculating the squareness of the packaging is: (5) In the formula, This represents the ratio of packaging squareness. The beneficial effects of this invention are: This invention provides an accurate, efficient, convenient, and stable solution for packaging squareness detection. Regarding accuracy, a high-precision flexible pressure sensor and precise calculation methods ensure the reliability of the detection results, accurately reflecting the squareness characteristics of the packaging and avoiding subjective errors inherent in traditional detection methods. In terms of efficiency, the automated detection process significantly shortens detection time, improves production efficiency, and enables companies to control product quality more quickly. Regarding ease of operation, simple operating steps and a highly automated process reduce the professional skills required of operators and minimize the impact of human factors on the detection results. In terms of stability and reliability, the system can operate stably for extended periods, providing strong support for continuous production. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the detection plate structure of a detection system and method for detecting the squareness of packaging based on flexible pressure according to the present invention. Figure 2 This is a schematic diagram of the pressure sensor layout of the present invention; Figure 3 This is a schematic diagram of the detection system of the present invention; Figure 4 This is a flowchart illustrating the detection method of the present invention.

[0028] In the diagram, 1 is the detection platform; 2 is the flexible pressure acquisition unit; 3 is the data acquisition and processing unit; 11 is the stage; 12 is the left detection pressure plate; 13 is the right detection pressure plate; 14 is the center positioning line; 21 is the pressure sensor; 22 is the distance sensor; 23 is the pressure sensor fixing slot; and 24 is the distance sensor fixing slot. Detailed Implementation

[0029] The related technologies of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0030] like Figures 1-4 As shown, the detection system for packaging squareness based on flexible pressure detection in this embodiment includes: a detection platform 1, a high-precision flexible pressure acquisition unit 2, and a data acquisition and processing unit 3.

[0031] The testing process and logic are as follows: The sample to be tested is fixed at the center of the adaptive testing platform via the sample positioning line. The large packaging surface of the sample to be tested is in contact with the pressure detection plate. After the sample is placed on the positioning line, the drive motor is started and the centering mechanism in the testing platform 1 is linked, so that the left and right pressure detection plates in the high-precision flexible pressure acquisition unit 2 move towards each other and approach the large packaging surface of the sample to be tested. The pressure detection plates start to collect pressure data at the same time. The detection plates are embedded with high-precision flexible pressure sensors 21. After the detection plates contact the packaging surface of the sample to be tested, the collected pressure data gradually increases. When the detected pressure data exceeds the limit, the drive motor of the pressure detection plates is turned off. After the sample to be tested is left to stand for a certain period of time, the motor drives the two detection plates to move forward by a designed displacement (1mm~2mm) towards the sample to be tested. The displacement of the detection plates is detected by the built-in distance sensor 22. At the same time as the motor starts, the pressure data of each contact surface is collected. The squareness of the sample packaging is evaluated based on the pressure distribution in the two pressure detection plates.

[0032] The high-precision flexible pressure acquisition unit 2 includes: multiple high-precision flexible pressure sensors 21, a sensor load panel, a reserved channel for data transmission lines, a ranging sensor 22, a pressure relay, etc. The sensor load panel is designed with embedded slots for flexible pressure sensors 21 and embedded slots for ranging sensors 22 on the contact surface between the sensor load panel and the sample to be tested. The embedded slots for pressure sensors 21 are preferably designed to be circular, with the circular slots being mutually circumscribed circles and arranged in a matrix. The embedded slots for ranging sensors 22 are preferably designed to be located at the center of the bottom of the load panel.

[0033] The testing platform 1 includes: a stage 11, a center positioning line 14, a centering linkage mechanism, a fixed plate, a drive motor, a guide rail, etc. The testing plate is located above the stage 11, and the center positioning line 14 is located at the center of the stage 11. It is preferably designed as a multi-level equally spaced centrally symmetrical graphic. The centering mechanism drives the two testing plates to move synchronously towards each other around the center positioning groove. The centering mechanism can preferably be designed as a linkage structure.

[0034] The data acquisition and processing unit 3 includes: a host computer, a pressure acquisition transmitter, a voltage conversion module, and a data transmission line. The acquired pressure is transmitted to the calculation program. When the real-time pressure data of adjacent points is less than or equal to a Pa, the average value of these adjacent pressure data is taken as the raw data for each acquisition point. The data processing system calculates the raw pressure distribution data according to the method for characterizing packaging squareness. Squareness (Sy) is used as the evaluation index for packaging squareness characteristics, representing the degree of regularity of the three-dimensional packaging. The closer the Sy value is to 1, the better the packaging squareness; the larger the Sy value, the worse the packaging squareness.

[0035] in: Methods for testing packaging squareness (Sy): The motion commands of the two detection plates need to be determined by the collected pressure data to give a start or stop signal. The determination method is calculated according to formulas (1) to (2): (1) (2) The squareness (Sy) calculation process is as follows: the pressure values ​​detected at the same horizontal position of the two detection plates are divided, and the side with the larger average pressure value of each detection plate is taken as the numerator. The data with a pressure ratio greater than or equal to 1 at each pressure detection point are added together, and the mean of the ratio of each pressure point participating in the statistics is further calculated. The closer the Sy value is to 1, the better the squareness of the packaging; the larger the Sy value, the worse the squareness of the packaging.

[0036] The formula is as follows: The left pressure plate is used to measure the average pressure. for: (3) The pressure average value of the pressure sensor plate on the right. for: (4) In the formula, m is the number of rows of flexible pressure sensors embedded in each pressure detection plate, and n is the number of columns of flexible pressure sensors embedded in each pressure detection plate. The pressure values ​​(i=1, ..., m; j=1, ..., n) collected by the sensors in the i-th row and j-th column of the left detection pressure plate are given in Pa. The pressure values ​​(i=1, ..., m; j=1, ..., n) collected by the sensors in the i-th row and j-th column of the right detection pressure plate are given in Pa. This represents the average pressure collected by the right pressure plate, in Pa. This represents the average pressure collected by the right pressure plate, in Pa.

[0037] (5) In the formula, For the squareness of the packaging.

[0038] Example: Example 1: The flexible pressure testing device for packaging squareness achieves contact between the left and right pressure testing plates and the sample to be tested through the centering mechanism and drive motor in the testing platform 1. The distance sensor 22 is used to precisely control the movement and displacement of the testing plates. The high-precision flexible pressure sensor 21 detects the pressure signals of each contact surface of the sample to be tested. The data acquisition and processing unit 3 converts the pressure signals at each point into pressure data, collects them in real time, and calculates the collected data according to the squareness calculation program.

[0039] The test was conducted using the squareness of cigarette pack packaging as the test object. The specific implementation steps are as follows: Step 1: Turn on the power to the detection device and the host computer in sequence. Place the cigarette box to be inspected on the center positioning line 14 of the stage 11, which can be fixed by adhesive.

[0040] Step 2: Start the left and right detection plate drive motors. The detection plates move closer to the cigarette box to be tested through the centering mechanism. After the detection plates contact the cigarette box to be tested, the data acquisition and processing unit 3 collects the contact surface pressure value in real time. The detection pressure value gradually increases as the contact distance decreases. Step 3: The data acquisition and processing unit 3 judges the pressure data according to formula (1). When the real-time acquired pressure value is greater than or equal to the limit pressure, the controller outputs an electrical signal to the contactor to control the detection board drive motor to stop running.

[0041] Step 4: After the drive motor stops for a certain period of time, the host computer outputs a motor start signal through the controller and contactor. The distance sensor 22 precisely controls the left and right pressure detection plates to move a certain distance towards the cigarette box to be inspected and then stop. In this embodiment, the distance is 2mm. The pressure data is collected as the moving distance increases and the contact pressure gradually increases.

[0042] Step 5: The host computer analyzes the raw data according to the data analysis program and formulas (3) and (4) to obtain the average detection pressure of the detection plate and calculate it: Step 6: Calculate the packaging squareness according to formula (5). Take the side with the larger average pressure as the numerator. Add up the data of each pressure detection point with a pressure ratio greater than or equal to 1. Further calculate the average ratio of each pressure point participating in the statistics. The closer the Sy value is to 1, the better the packaging squareness; the larger the Sy value, the worse the packaging squareness.

[0043] Example 2: Cigarette cartons produced by different packaging machines were tested. One carton was randomly sampled from each machine, and one carton was tested each time, with 10 cartons tested per carton. The results are shown in Table 1 below:

[0044] The average squareness of 10 packs of cigarette boxes tested on machine #1 was 0.24, significantly higher than that tested on machine #2, indicating that machine #2 produced better squareness. This demonstrates that the testing device and method can effectively quantify and evaluate the differences in the squareness of cigarette box packaging.

[0045] In summary, this invention achieves effective detection of the squareness of packaging such as cigarette boxes. In practical applications, this detection system and method significantly improves the accuracy and efficiency of detection, and can accurately quantify the squareness characteristics of the packaging. Compared with traditional detection methods, this invention utilizes a high-precision flexible pressure sensor and advanced calculation methods, transforming squareness detection from subjective judgment to objective and accurate quantitative analysis.

[0046] It plays a crucial role in improving packaging quality. By promptly detecting products with substandard packaging squareness, it prevents these products from entering the market, thus protecting brand image and consumer satisfaction. Simultaneously, for manufacturers, it enables targeted process improvements and quality control, reducing scrap rates and increasing production efficiency.

[0047] In terms of ease of operation, the system offers a superior user experience. Operators simply need to place the sample and start the motor according to the predetermined steps to complete the testing process. The entire process is highly automated, minimizing human error. Furthermore, the system's stability and reliability have been proven in practice, enabling it to operate stably for extended periods and providing strong support for the company's continuous production. It should be emphasized that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any way. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A system for detecting the squareness of a flexible pressure detecting package, characterized by, The utility model relates to a kind of detection method and detection system of squareness of sample, including: Detection platform (1) is used to be pressed and clamped by pressure flat along horizontal direction from two large-area opposite outer facade of cuboid sample to be detected to sample to be detected is adhered to each other inwardly; Flexible pressure acquisition unit (2) is used to detect the pressure distribution of the pressure surface of sample to be detected when being pressed in two opposite directions; Data acquisition and processing unit (3) is used to collect, calculate and analyze the pressure distribution data detected by the flexible pressure acquisition unit (2), so as to determine the squareness of sample to be detected; The pressure sensor (21) of the flexible pressure acquisition unit (2) is arranged on the outer side of the pressure flat of the detection platform (1) towards sample to be detected, and the flexible pressure acquisition unit (2) is electrically connected to the data acquisition and processing unit (3).

2. The system for detecting the squareness of a flexible pressure detecting package according to claim 1, wherein The detection platform (1) includes a stage (11), a left detection pressure plate (12) and a right detection pressure plate (13), the left detection pressure plate (12) and the right detection pressure plate (13) are respectively slidably connected to the upper surface of the stage (11), and the left detection pressure plate (12) and the right detection pressure plate (13) are oppositely arranged. When the left detection pressure plate (12) and the right detection pressure plate (13) slide towards each other, the left detection pressure plate (12) and the right detection pressure plate (13) are respectively adhered to the two opposite outer facades of sample to be detected.

3. The system for detecting the squareness of a flexible pressure detecting package according to claim 2, wherein The upper surface of the stage (11) is provided with a center positioning line (14) in the middle, and the left detection pressure plate (12) and the right detection pressure plate (13) are controlled to slide through the center linkage mechanism.

4. The system for detecting the squareness of a flexible pressure detecting package according to claim 2, wherein The flexible pressure acquisition unit (2) includes a pressure sensor (21), a distance measuring sensor (22), a pressure sensor fixing groove (23) and a distance measuring sensor fixing groove (24), the pressure sensor (21) and the distance measuring sensor (22) are arranged on the facade of the left detection pressure plate (12) and the right detection pressure plate (13) adhered to sample to be detected, the pressure sensor (21) is arranged in the pressure sensor fixing groove (23), and the distance measuring sensor (22) is arranged in the distance measuring sensor fixing groove (24).

5. The system for detecting the squareness of a flexible pressure detecting package according to claim 4, wherein The pressure sensor fixing groove (23) is in the shape of a cylindrical groove, a square groove or an oval groove, the central axis of the pressure sensor fixing groove (23) is perpendicular to the facade of the respective pressure plate, and the pressure sensor fixing grooves (23) are arrayed and uniformly distributed on the facade of the respective pressure plate, and the distance measuring sensor fixing groove (24) is arranged at the lower middle position of the left detection pressure plate (12) and the right detection pressure plate (13).

6. The system for detecting the squareness of a flexible pressure detecting package according to claim 5, wherein When the pressure sensor fixing groove (23) is in the shape of a cylindrical groove, the cylindrical surfaces of two adjacent pressure sensor fixing grooves (23) are mutually tangent.

7. A method for detecting the squareness of a flexible pressure detection package, characterized by, The detection method adopts the detection system of any one of claims 1 to 6, and the detection method comprises the following steps: Step 1: turn on the power supply of the detection platform, the flexible pressure acquisition unit, the data acquisition and processing unit and the upper computer, ensure the power supply connection of the detection mechanism, and the flexible pressure acquisition unit and the data acquisition and processing unit enter the detection state; place the sample to be detected on the center positioning line of the stage. Step 2: The flexible pressure acquisition unit acquires the contact surface pressure value in real time by driving the left and right detection pressure plates to move towards each other to contact the sample to be measured, and the contact surface pressure value gradually increases as the distance between the left and right detection pressure plates decreases; Step 3: The data acquisition and processing unit determines the pressure data, and when the real-time acquisition pressure value is greater than or equal to the limited pressure, the left and right detection pressure plate translation drive motor stops; Step 4: After the motor stops for a unit time, the motor is restarted and the left and right detection pressure plates are moved by a small distance to the sample to be measured and then stopped under the control of the distance measuring sensor, and the pressure data of each pressure sensor is acquired; Step 5: The data acquisition and processing unit calculates the pressure distribution data: Step 6: The data acquisition and processing unit evaluates the packaging squareness of the sample to be measured by the pressure ratio of the left and right detection pressure plates, and the closer the ratio is to 1, the better the packaging squareness; the farther the ratio deviates from 1, the worse the packaging squareness.

8. The method of claim 7, wherein the method is based on a flexible pressure detection package orthogonality detection method. In step 4, the unit time is 1-5 seconds, and the distance is 0.5-2.5 mm.

9. The method of claim 7, wherein the method is based on a flexible pressure detection package orthogonality detection method. In step 3, the pressure data determination formula for stopping the left and right detection pressure plate drive motor is: （1） （2） wherein, represents the maximum pressure value collected by the pressure detection plate, represents the pressure value collected by the i-th row and j-th column of the pressure detection plate, m and n are respectively the number of rows and columns of the pressure sensor, i and j are respectively the i-th row and j-th column of the pressure sensor, represents the limit pressure value at which the pressure detection plate stops moving.

10. The method of claim 7, wherein the method is based on a flexible pressure detection package orthogonality detection method. In step 5, the calculation formula of the pressure distribution data is: left detection pressure plate pressure average value is: （3） right detection pressure plate pressure average value is: （4） In the formula, Pi,j is the pressure value collected by the i-th row, j-th column sensor of the left detection pressure plate, Pi,j is the pressure value collected by the i-th row, j-th column sensor of the right detection pressure plate, i = 1, …, m; j=1, …, n; In step 6, the calculation formula of the packaging squareness is: （5） In the formula, is the packing squareness ratio.

Images