A corrugated cardboard box compressive strength testing device and method

Abstract

The present invention belongs to the technical field of compressive strength detection, in particular to a corrugated cardboard box compressive strength detection device and method. The device includes a flat plate and a pressing plate. A hydraulic rod is connected to the top of the pressing plate. A plurality of sliding grooves are opened at the bottom of the pressing plate. The two sides of the sliding grooves penetrate. A limiting groove is opened at the top of the sliding grooves. A sliding plate is slidably connected to the inner wall of the sliding grooves. The outer wall of the bottom of the sliding plate is flush with the bottom of the pressing plate. Sliders are installed on both sides of the top of the sliding plate, and the sliders are slidably limited in the limiting grooves. In the process of compressive strength detection, the present invention can identify and detect small bending or damage conditions of the cardboard box, thereby improving the accuracy of compressive strength detection, and can ensure that the top surface of the cardboard box is always vertically pressed with a complete plane during continuous downward pressing.

Description

Technical Field

[0001] The present invention relates to the technical field of compressive strength detection, and particularly relates to a corrugated cardboard box compressive strength detection device and method. Background Art

[0002] The equipment for detecting the compressive strength of corrugated cardboard boxes generally refers to a cardboard box pressure testing machine, also known as a cardboard box compressive strength tester or a cardboard box compressive testing machine.

[0003] Referring to the Chinese patent with the patent publication number CN118243522B, a corrugated cardboard box compressive strength detection equipment and detection method are disclosed. Among them, a corrugated cardboard box compressive strength detection equipment includes a base, a support frame arranged on the base, a transmission gear one arranged on the support frame, and a chain arranged on the transmission gear one. It also includes a pressure testing unit arranged on the support frame and a power unit arranged in the base, and the power unit is connected to the chain.

[0004] In the prior art, for the sampling detection of corrugated cardboard boxes, generally, only the upper pressing plate presses down on the top of the corrugated cardboard box until the corrugated cardboard box is damaged. However, since it is difficult to judge the degree of damage of the corrugated cardboard box, it is often only discovered when there is a large degree of damage, which will result in inaccurate actual detection results. Summary of the Invention

[0005] Based on the technical problems existing in the background art, the present invention proposes a corrugated cardboard box compressive strength detection device and method.

[0006] A corrugated cardboard box compressive strength detection device proposed by the present invention includes a flat plate and a pressing plate. A hydraulic rod is connected to the top of the pressing plate. A plurality of sliding grooves are opened at the bottom of the pressing plate, and both sides of the sliding grooves penetrate. A limiting groove is opened at the top of the sliding grooves. A sliding plate is slidably connected to the inner wall of the sliding grooves. The bottom outer wall of the sliding plate is flush with the bottom of the pressing plate. Sliding blocks are installed on both sides of the top of the sliding plate, and the sliding blocks are limited and slide in the limiting grooves.

[0007] Furthermore, extension shafts are fixed at both ends of the sliding blocks, and extension sleeves are rotatably connected to the outer walls of the extension shafts. The extension sleeves are in rolling contact with the inner wall of the limiting grooves. A magnetic attraction sheet is installed at the middle position of the top of the sliding plate, and an electromagnetic block is fixed at the middle position of the inner wall of the top of the limiting groove.

[0008] Furthermore, turntables are arranged at the four corner positions of the flat plate. The top outer wall of the turntables is flush with the top outer wall of the flat plate. Air pipes are installed on the turntables. The top ends of the air pipes are flush with the tops of the turntables, and the bottom ends of the air pipes are connected to air pumps.

[0009] Further, the turntable is provided with a rotating plate and a rotating ring. The rotating ring is installed at the bottom end of the rotating plate. The rotating ring extends downward to the lower part of the outer wall of the bottom of the flat plate. The outer diameter of the rotating ring is smaller than that of the rotating plate. A toothed ring is installed at the bottom of the outer wall of the turntable.

[0010] Further, an electric push rod is installed at the bottom of the flat plate. One end of the electric push rod is connected with a driving frame. The position of the driving frame corresponding to the turntable is set as a rack. The rack is arranged parallel to the extending direction of the electric push rod. The rack meshes with the toothed ring.

[0011] Further, a connecting groove is opened at the position of the outer side of the pressing plate corresponding to the air pipe. A side bar extending vertically downward is connected in the connecting groove in a limited sliding manner. A horizontal bar is arranged at the bottom of the outer side of the side bar. A vertical through groove is opened at the middle position of the horizontal bar. An air pressure intensity sensor is installed in the vertical through groove.

[0012] Further, a pressure sensor is connected between the hydraulic rod and the pressing plate. The pressure sensor is used to monitor the extrusion force between the hydraulic rod and the pressing plate in real time. A distance sensor is installed on the side of the limiting groove. The distance sensor is used to monitor the distance between the distance sensor and the corresponding slider.

[0013] A corrugated cardboard box compressive strength detection method, according to the above-mentioned corrugated cardboard box compressive strength detection device, includes the following steps:

[0014] Step 1: Before placing the cardboard box, rotate the air pipes at the four corners to the inside.

[0015] Step 2: When placing the cardboard box, make the bottom of the cardboard box cover the air pipes at the four corners. After placing the cardboard box, slide the side bars corresponding to the positions of the respective air pipes into the connecting grooves so that the side bars are attached to the surface of the cardboard box.

[0016] Step 3: Make the top ends of the air pipes inhale downward.

[0017] Step 4: Lower the pressing plate until it fits the top surface of the cardboard box. Stop the inhalation operation of the air pipes and restore the air pressure in the air pipes to normal. Rotate the air pipes to the outside of the cardboard box.

[0018] Step 5: The pressing plate continues to press down for compressive strength detection. When the cardboard box is locally cracked and bent, the top surface of the cardboard box will tilt. The reverse force of the tilt causes the corresponding sliding plate to slide horizontally. The top ends of the air pipes blow air upward.

[0019] The pressure sensor is used to monitor the extrusion force between the hydraulic rod and the pressing plate in real time. The distance sensor is used to monitor the distance between the distance sensor and the corresponding slider. The air pressure intensity sensor is used to monitor the air flow intensity generated by blowing air through the air pipes at the corresponding positions in real time. Upload the monitored values to the central processing unit, and calculate the evaluation coefficient through comprehensive analysis.

[0020] Furthermore, the calculation and acquisition logic of the evaluation coefficient:

[0021] Step 1: Denote the real-time monitoring data of the pressure sensor as P; denote the real-time monitoring data of the distance sensor as D; denote the real-time monitoring data of the air pressure intensity sensor as A.

[0022] Step 2: The calculation formula of the evaluation coefficient E:

[0023] ,

[0024] In the formula, , and are weight coefficients, and , and the weights can be determined through multiple experiments by analyzing the correlation degree between the data of each sensor and the actual damage situation of the carton; among them, is the predicted maximum pressure value measured when the carton is completely damaged, is the maximum distance value predicted to be measured by the distance sensor when the sliding plate offsets to the limit position, is the maximum air pressure intensity value measured by the air pressure intensity sensor when the carton is not damaged;

[0025] Step 3: Analyze the evaluation coefficient E and the reference coefficient:

[0026] If E is greater than the reference coefficient, it indicates that the carton is damaged;

[0027] If E is less than the reference coefficient, the carton is still within the normal use range.

[0028] The beneficial effects of the present invention are as follows:

[0029] 1. In the present invention, when the top surface of the carton is inclined and the pressing plate continues to press down, the sliding plate will offset and slide towards one side due to the reverse force of the inclined top surface of the carton, so that it can identify and detect minor bending or damage of the carton during the compression test, thereby improving the accuracy of the compression test, and can ensure that the top surface of the carton is always vertically pressed with a complete plane during the continuous pressing process.

[0030] 2. In the present invention, through the setting of the bottom turntable and the air pipe, the stability of the carton placement and the flatness effect of the bottom are maintained by the air pipe before the pressing plate contacts the carton, and the bottom flatness is maintained by the turntable during the extrusion test, thereby improving the accuracy of the compression test during the overall use process.

[0031] 3. In the present invention, by comprehensively analyzing the extrusion force of monitoring the position of the hydraulic rod, the offset distance of the sliding plate, and the air pressure change caused by the offset of the side strip, the effectiveness and accuracy of detecting the change in the damage degree of the carton are improved. Description of the Drawings

[0032] Figure 1 Schematic diagram of the overall structure of a corrugated cardboard box compression testing device proposed in Embodiment 1 of the present invention;

[0033] Figure 2 Schematic diagram of the pressing plate structure of a corrugated cardboard box compression testing device proposed by the present invention;

[0034] Figure 3 Schematic diagram of the internal structure of the limiting groove of a corrugated cardboard box compression testing device proposed in Embodiment 1 of the present invention;

[0035] Figure 4 Schematic diagram of the chute and limiting groove structure of a corrugated cardboard box compression testing device proposed by the present invention;

[0036] Figure 5 Schematic diagram of the sliding plate structure of a corrugated cardboard box compression testing device proposed by the present invention;

[0037] Figure 6 Schematic diagram of the first usage state of the turntable of a corrugated cardboard box compression testing device proposed by the present invention;

[0038] Figure 7 Schematic diagram of the second usage state of the turntable of a corrugated cardboard box compression testing device proposed by the present invention;

[0039] Figure 8 Schematic diagram of the driving frame structure of a corrugated cardboard box compression testing device proposed by the present invention;

[0040] Figure 9 Schematic diagram of the turntable structure of a corrugated cardboard box compression testing device proposed by the present invention;

[0041] Figure 10 Schematic diagram of the overall structure of a corrugated cardboard box compression testing device proposed in Embodiment 2 of the present invention;

[0042] Figure 11 For a corrugated cardboard box compression testing device proposed by the present invention Figure 10 Enlarged structure schematic diagram of part A;

[0043] Figure 12 Schematic diagram of the position structure of the connecting groove of a corrugated cardboard box compression testing device proposed by the present invention;

[0044] Figure 13 Schematic diagram of the internal structure of the limiting groove of a corrugated cardboard box compression testing device proposed in Embodiment 2 of the present invention.

[0045] In the figure: 1 flat panel, 2 cardboard box, 3 support frame, 4 hydraulic rod, 5 pressure plate, 501 chute, 502 limiting groove, 503 connecting groove, 6 sliding plate, 7 slider, 701 extension shaft, 702 extension sleeve, 8 magnetic sheet, 9 electromagnetic block, 10 base, 11 turntable, 111 rotating plate, 112 rotating ring, 12 air pipe, 13 toothed ring, 14 drive frame, 15 electric push rod, 16 stabilizing frame, 17 side bar, 171 connecting block, 172 horizontal bar, 18 air pressure intensity sensor, 19 distance sensor. Detailed implementation mode

[0046] Example 1: Refer to Figures 1-9 , a corrugated cardboard box compression testing device, including a flat panel 1 and a pressure plate 5. The cardboard box 2 is placed on the flat panel 1. The top of the pressure plate 5 is connected to a hydraulic rod 4. A support frame 3 is installed between the hydraulic rod 4 and the flat panel 1. Multiple chutes 501 are opened at the bottom of the pressure plate 5. The two sides of the chutes 501 penetrate. The multiple chutes 501 are arranged in parallel. A limiting groove 502 is opened at the top of the chutes 501. The width of the limiting groove 502 is greater than the width of the chutes 501. The inner wall of the chutes 501 is slidably connected to a sliding plate 6. The bottom outer wall of the sliding plate 6 is flush with the bottom of the pressure plate 5. Sliders 7 are installed on both sides of the top of the sliding plate 6. The sliders 7 are limited and slide in the limiting groove 502. It should be noted that: before the compression test, the sliding plate 6 is placed in the middle position of the chutes 501, that is, both sides of the sliding plate 6 are flush with both sides of the pressure plate 5, and the cross-section of the pressure plate 5 is much larger than the cross-section of the cardboard box 2; and in the process of placing the cardboard box 2 on the flat panel 1 and then lowering the pressure plate 5 through the hydraulic rod 4 for the compression test, since the cross-section of the pressure plate 5 is much larger than the cross-section of the cardboard box 2, it can ensure that the bottom surface of the pressure plate 5 can completely cover the top surface of the cardboard box 2 for the extrusion test operation, and during the test: on the one hand, through the horizontally slidable setting of the sliding plate 6, when the cardboard box 2 is squeezed and there are bending deformations at other positions that cannot be quickly detected, the top surface of the cardboard box 2 will tilt due to the deformations at other places. When the top surface of the cardboard box 2 tilts and the pressure plate 5 continues to press down, the sliding plate 6 will shift and slide towards one side due to the reaction force of the tilt of the top surface of the cardboard box 2. Thus, it can identify and detect smaller bending or damage conditions of the cardboard box 2 during the compression test, thereby improving the accuracy of the compression test; on the other hand, through the limited sliding setting of the sliding plate 6, the sliding plate 6 can only slide horizontally, and through the settings that the widths of the pressure plate 5 and the sliding plate 6 are much larger than the cardboard box 2, even if the sliding plate 6 slides a short distance, it can ensure the coverage of the top surface of the cardboard box 2. Therefore, during the continuous pressing process, it can ensure that the top surface of the cardboard box 2 is always vertically pressed with a complete plane until the cardboard box 2 is damaged, thereby further improving the accuracy and effectiveness of the compression resistance test of the cardboard box 2.

[0047] In the present invention, extension shafts 701 are fixed at both ends of the slider 7. The outer wall of the extension shaft 701 is rotatably connected with an extension sleeve 702. The extension sleeve 702 is in rolling contact with the inner wall of the limiting groove 502. By means of the extension shafts 701 and the extension sleeves 702 that horizontally extend towards both ends, the slider 7 is limited, so that the sliding plate 6 and the slider 7 can only horizontally move along the extending direction of the sliding groove 501, ensuring the flatness of the downward extrusion. The rolling-connected extension sleeve 702 is used to reduce the friction of the horizontal movement of the sliding plate 6 and the slider 7, ensuring the sliding effect of the reverse force applied by the sliding plate 6 after the top surface of the cardboard box 2 is tilted;

[0048] A magnetic attraction sheet 8 is installed at the middle position between the two sliders 7 at the top of the sliding plate 6. An embedding groove is formed at the middle position of the inner wall of the top of the limiting groove 502. An electromagnetic block 9 is fixed on the inner wall of the embedding groove. When the pressing plate 5 is lifted, and during the process of the pressing plate 5 descending from the topmost position to just contacting the top surface of the cardboard box 2, the electromagnetic block 9 is energized to magnetically adsorb with the magnetic attraction sheet 8, so as to keep the sliding plate 6 at the middle position of the sliding groove 501, and the two sides of the sliding plate 6 are just aligned with the two sides of the pressing plate 5, facilitating observation during the compressive strength test; at the same time, the electromagnetic block 9 is used to limit the two side sliders 7 to prevent the sliding plate 6 from sliding out from the side during normal placement, ensuring the effectiveness of the long-term use of the equipment.

[0049] In the present invention, turntables 11 are arranged at the four corners of the flat plate 1. The top outer wall of the turntable 11 is flush with the top outer wall of the flat plate 1. An air pipe 12 is installed on the turntable 11. The top end of the air pipe 12 is flush with the top of the turntable 11. The bottom end of the air pipe 12 is connected with an air pump. A plurality of bases 10 are installed on the outside of the flat plate 1, and the flat plate 1 is horizontally arranged through the plurality of bases 10; it should be noted that: the positions of the turntables 11 and the air pipes 12 correspond to the size of the cardboard box 2. For cardboard boxes 2 of different sizes, different flat plates 1 and corresponding turntables 11 can be pre-selected;

[0050] During the process of placing the cardboard box 2, as Figure 7 shown in the usage state two: rotate the air pipe 12 on the turntable 11 to a position close to the center of the flat plate 1; during the placement of the cardboard box 2, the four corners of the cardboard box 2 just block the top ends of the air pipes 12 on the four turntables 11;

[0051] When the pressing plate 5 gradually descends from the topmost position to close to the top surface of the cardboard box 2: the air pump is used to suck air downward through the air pipe 12, generating a suction force between the top end of the air pipe 12 and the bottom position of the cardboard box 2. The cardboard box 2 is stabilized through the suction force at the four corners below the cardboard box 2 until the pressing plate 5 contacts the top surface of the cardboard box 2, and the bottom of the cardboard box 2 is kept flat before being pressed through the suction force at the four corner positions;

[0052] Then, before the pressing plate 5 continues to press down, as Figure 6The first usage state shown: The turntable 11 rotates to turn the air pipe 12 out of the carton 2; By using other positions of the turntable 11 to be flush with the top of the flat plate 1, it is ensured that the bottom surface of the carton 2 is in flat contact during the process of the pressing plate 5 squeezing the top surface of the carton 2; Thus, the accuracy of the compressive strength test during the overall usage process is improved.

[0053] In the present invention, the turntable 11 is provided with a rotating plate 111 and a rotating ring 112. The rotating ring 112 is installed at the bottom end of the rotating plate 111. The rotating ring 112 extends downward to the lower part of the outer wall of the bottom of the flat plate 1. The outer diameter of the rotating ring 112 is smaller than the outer diameter of the rotating plate 111. It should be noted that: corresponding positions of the flat plate 1 and the turntable 11 are provided with a rotating groove and a rotating hole distributed from top to bottom. The rotating hole is located below the rotating groove. The inner diameter of the rotating groove is larger than the inner diameter of the rotating hole. The outer wall of the rotating plate 111 is in sliding contact with the inner wall of the rotating groove. The outer wall of the rotating ring 112 is in sliding contact with the inner wall of the rotating hole; A toothed ring 13 is installed at the bottom of the outer wall of the turntable 11. It should be noted that: the toothed ring 13 is installed on the outer wall of the rotating ring 112, and the toothed ring 13 is located at the lower position of the outer wall of the bottom of the flat plate 1.

[0054] In the present invention, an electric push rod 15 is installed at the bottom of the flat plate 1. One end of the electric push rod 15 is connected with a driving frame 14. The position of the driving frame 14 corresponding to the turntable 11 is set as a rack. The rack is arranged parallel to the extending direction of the electric push rod 15. The rack is meshed with the toothed ring 13. It should be noted that: stabilizing frames 16 are installed at both ends of the bottom of the flat plate 1. The bottom outer wall of the driving frame 14 is in sliding contact with the stabilizing frames 16. During the process of the electric push rod 15 reciprocally moving the driving frame 14, the stabilizing frames 16 are used to improve the stability of the driving frame 14 during use; Thus, by driving the driving frame 14 to reciprocally move horizontally through the electric push rod 15, the rack on the driving frame 14 can be meshed with the toothed ring 13 outside the turntable 11 to drive the turntable 11 to reciprocally deflect, thereby realizing the movement and replacement of the position of the air pipe 12 on the turntable 11.

[0055] A method for testing the compressive strength of a corrugated carton, according to the above-mentioned device for testing the compressive strength of a corrugated carton, includes the following steps:

[0056] Step 1: Before placing the carton, rotate the air pipes 12 at the four corner positions to the inside;

[0057] Step 2: When placing the carton, cover the air pipes 12 at the four corner positions with the bottom of the carton;

[0058] Step 3: Make the top end of the air pipe 12 inhale downward, so that the carton is placed stably and the bottom of the carton is flattened by the suction at the four corner positions;

[0059] Step 4: The pressing plate 5 descends to fit with the top surface of the carton, stop the suction operation of the air pipe 12 and make the air pressure in the air pipe 12 return to normal, and rotate the air pipe 12 to the outside of the carton;

[0060] Step Five: The pressing plate 5 continues to press down for compressive strength detection. When the local part of the carton is broken and bent, the top surface of the carton will tilt, and the reverse force of the tilt causes the corresponding sliding plate 6 to slide horizontally, so as to observe and monitor the possible local small breakage and bending through the sliding of the sliding plate 6.

[0061] Embodiment 2: Refer to Figure 2 and Figures 4-13 , a corrugated carton compressive strength detection device. On the basis of Embodiment 1, a connection groove 503 is opened at the position corresponding to the air pipe 12 on the outside of the pressing plate 5. A side strip 17 extending vertically downward is connected in the connection groove 503 in a limited sliding manner. It should be noted that: the bottom of the connection groove 503 is penetrated, and the bottom end of the connection groove 503 is of a reduced opening structure. The top end of the side strip 17 is connected with a connecting block 171 of a spherical structure, and the connecting block 171 is limited to slide in the connection groove 503; a horizontal strip 172 is arranged at the bottom outside the side strip 17, and a vertical through groove is opened in the middle position of the horizontal strip 172. A pneumatic pressure intensity sensor 18 is installed in the vertical through groove. When the pressing plate 5 descends to fit with the top surface of the carton 2, the side strip 17 approaches the carton 2 in the horizontal direction and will not cause extrusion force on the outside of the carton 2, thus avoiding excessive force and affecting the accuracy of the detection. And the horizontal strip 172 and the pneumatic pressure intensity sensor 18 are exactly above the air pipe 12 that rotates to the outside during the detection process. During the detection process, the air pipe 12 blows air slightly upward through the air pump, so that the pneumatic pressure intensity sensor 18 can detect the value, and the blowing air is blocked by the side strip 17 and the horizontal strip 172 and will not cause excessive force on the edge position of the carton 2. When a slight bend that is not easy to detect occurs at the corner position of the carton 2, the side strip 17 will slide horizontally due to the contact with the bend of the carton 2, so that the pneumatic pressure intensity sensor 18 below deviates from the vertically upward blowing air, resulting in a decrease in the detected value, so as to cooperate to improve the accuracy of the compressive strength detection.

[0062] In the present invention, a pressure sensor is connected between the hydraulic rod 4 and the pressing plate 5. The pressure sensor is used to monitor the extrusion force between the hydraulic rod 4 and the pressing plate 5 in real time, so as to monitor the compressive strength in various situations during the extrusion process; a distance sensor 19 is installed on the side of the limiting groove 502. The distance sensor 19 is used to monitor the distance between the distance sensor 19 and the corresponding slider 7, so as to immediately monitor and identify through the distance sensor 19 when the sliding plate 6 deviates.

[0063] A corrugated carton compressive strength detection method. According to the above-mentioned corrugated carton compressive strength detection device, it includes the following steps:

[0064] Step One: Before placing the carton, rotate the air pipes 12 at the four corner positions to the inside;

[0065] Step 2: When placing the carton, cover the air pipes 12 at the four corners with the bottom of the carton; after placing the carton, slide the side strips 17 corresponding to the positions of the respective air pipes 12 into the connection grooves 503 so that the side strips 17 are in contact with the surface of the carton;

[0066] Step 3: Make the top ends of the air pipes 12 suck air downward so that the carton is stably placed and the bottom of the carton is flattened by sucking air at the four corners;

[0067] Step 4: The pressing plate 5 descends to be in contact with the top surface of the carton, stop the air suction operation of the air pipes 12 and make the air pressure in the air pipes 12 return to normal, and rotate the air pipes 12 to the outside of the carton;

[0068] Step 5: The pressing plate 5 continues to press down for compressive strength detection. When the carton is locally broken and bent, the top surface of the carton will be inclined, and the reverse force of the inclination makes the corresponding sliding plate 6 slide horizontally, so as to observe and monitor the possible local small breakage and bending through the sliding of the sliding plate 6, and the top ends of the air pipes 12 blow air upward;

[0069] The pressure sensor is used to monitor the extrusion force between the hydraulic rod 4 and the pressing plate 5 in real time. The distance sensor 19 is used to monitor the distance between the distance sensor 19 and the corresponding slider 7. The air pressure intensity sensor 18 is used to monitor the air flow intensity generated by blowing air through the air pipes 12 at the corresponding positions in real time. Upload the monitored values to the central processor, calculate the evaluation coefficient through comprehensive analysis, and compare the evaluation coefficient with the reference coefficient. If the evaluation coefficient is greater than the reference coefficient, it means that the carton is damaged in this state. If the evaluation coefficient is less than the reference coefficient, it means that the carton is still within the normal use range in this state. Therefore, through the comprehensive analysis of the extrusion force monitoring at the position of the hydraulic rod 4, the offset distance monitoring of the sliding plate 6, and the air pressure change caused by the offset of the side strip 17, the effectiveness and accuracy of the detection of the change in the damage degree of the carton are improved.

[0070] In the present invention, the calculation and acquisition logic of the evaluation coefficient:

[0071] Step 1: The real-time monitoring data of the pressure sensor is recorded as P; the real-time monitoring data of the distance sensor 19 is recorded as D; the real-time monitoring data of the air pressure intensity sensor 18 is recorded as A;

[0072] Step 2: The calculation formula of the evaluation coefficient E:

[0073] ,

[0074] In the formula, , and are weight coefficients, and , and the weights can be determined through multiple experiments and analyzing the correlation degree between the data of each sensor and the actual damage situation of the carton; among them, It is the predicted maximum pressure value measured when the cardboard box is completely damaged and can be set through multiple historical records. It represents the ratio of the current pressure to the maximum pressure and is used to measure the contribution of pressure to the damage of the cardboard box. It is the maximum distance value predicted to be measured by the distance sensor when the sliding plate offsets to the extreme position and can be pre-determined through multiple historical records. It represents the ratio of the current offset distance of the sliding plate to the maximum offset distance and reflects the influence of the sliding plate offset on the judgment of cardboard box damage. It is the maximum air pressure intensity value measured by the air pressure intensity sensor when the cardboard box is not damaged. It represents the change ratio of the current air pressure intensity relative to the normal state and reflects the role of air pressure change in the detection of cardboard box damage.

[0075] Step Three: Analyze the evaluation coefficient E and the reference coefficient.

[0076] If E is greater than the reference coefficient, it indicates that the cardboard box is damaged.

[0077] If E is less than the reference coefficient, the cardboard box is still within the normal use range.

[0078] As described above, it is only the preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

Claims

1. A corrugated cardboard box compressive strength detection device, comprising a flat plate (1) and a pressing plate (5), wherein a hydraulic rod (4) is connected to the top of the pressing plate (5), and is characterized in that, A plurality of sliding grooves (501) are formed at the bottom of the pressing plate (5). Both sides of the sliding groove (501) penetrate through. A limiting groove (502) is formed at the top of the sliding groove (501). A sliding plate (6) is slidably connected to the inner wall of the sliding groove (501). The bottom outer wall of the sliding plate (6) is flush with the bottom of the pressing plate (5). Sliders (7) are installed on both sides of the top of the sliding plate (6). The sliders (7) are slidably limited in the limiting groove (502). Extension shafts (701) are fixed at both ends of the slider (7). The outer wall of the extension shaft (701) is rotatably connected to an extension sleeve (702). The extension sleeve (702) is in rolling contact with the inner wall of the limiting groove (502). A magnetic sheet (8) is installed at the middle position of the top of the sliding plate (6). An electromagnet (9) is fixed at the middle position of the inner wall of the top of the limiting groove (502).

2. The corrugated cardboard box compression testing device according to claim 1, wherein, Rotary discs (11) are arranged at the four corner positions of the flat plate (1). The top outer wall of the rotary disc (11) is flush with the top outer wall of the flat plate (1). An air pipe (12) is installed on the rotary disc (11). The top end of the air pipe (12) is flush with the top of the rotary disc (11). The bottom end of the air pipe (12) is connected to an air pump.

3. The corrugated cardboard box compressive strength detection device according to claim 2, characterized in that, The rotary disc (11) is provided with a rotating plate (111) and a rotating ring (112). The rotating ring (112) is installed at the bottom end of the rotating plate (111). The rotating ring (112) extends downward to below the bottom outer wall of the flat plate (1). The outer diameter of the rotating ring (112) is smaller than the outer diameter of the rotating plate (111). A toothed ring (13) is installed at the bottom of the outer wall of the rotary disc (11).

4. A corrugated cardboard box compressive strength detection device according to claim 3, characterized in that, An electric push rod (15) is installed at the bottom of the flat plate (1). One end of the electric push rod (15) is connected to a driving frame (14). The position of the driving frame (14) corresponding to the rotary disc (11) is set as a rack. The rack is arranged parallel to the extending direction of the electric push rod (15). The rack is meshed with the toothed ring (13).

5. The corrugated cardboard box compressive strength detection device according to claim 2, characterized in that, A connection groove (503) is formed at the position of the pressing plate (5) corresponding to the air pipe (12). A side bar (17) extending vertically downward is slidably limited in the connection groove (503). A horizontal bar (172) is arranged at the bottom of the outer side of the side bar (17). A vertical through groove is formed at the middle position of the horizontal bar (172). A pneumatic pressure sensor (18) is installed in the vertical through groove.

6. The corrugated cardboard box compression testing device according to claim 5, wherein A pressure sensor is connected between the hydraulic rod (4) and the pressing plate (5). The pressure sensor is used to monitor the extrusion force between the hydraulic rod (4) and the pressing plate (5) in real time. A distance sensor (19) is installed on the side of the limiting groove (502). The distance sensor (19) is used to monitor the distance between the distance sensor (19) and the corresponding slider (7).

7. A method for detecting the compressive strength of a corrugated cardboard box, according to the corrugated cardboard box compressive strength detection device described in claim 6, characterized in that, Including the following steps: Step 1: Before placing the carton, rotate the air pipes (12) at the four corner positions to the inner side. Step 2: When placing the carton, cover the air pipes (12) at the four corner positions with the bottom of the carton. Step 3: Make the top end of the air pipe (12) suck air downward. Step 4: Lower the pressing plate (5) until it fits against the top surface of the carton. Stop the air suction operation of the air pipe (12) and restore the air pressure in the air pipe (12) to normal. Rotate the air pipe (12) to the outside of the carton. Step Five: The pressing plate (5) continues to press down for compressive strength detection. When the local part of the cardboard box is broken and bent, the top surface of the cardboard box will tilt, and the reverse force of the tilt causes the corresponding sliding plate (6) to slide horizontally.

8. A method for detecting the compressive strength of a corrugated cardboard box according to claim 7, characterized in that, In Step Two, after placing the cardboard box, slide the side strips (17) corresponding to the positions of the respective air pipes (12) into the connection grooves (503) so that the side strips (17) are in contact with the surface of the cardboard box. In Step Five, the top end of the air pipe (12) blows air upward. In Step Five, the pressure sensor is used to monitor the extrusion force between the hydraulic rod (4) and the pressing plate (5) in real time. The distance sensor (19) is used to monitor the distance between the distance sensor (19) and the corresponding slider (7). The air pressure intensity sensor (18) is used to monitor the air flow intensity generated by blowing air through the air pipe (12) at the corresponding position in real time. The monitored values are uploaded to the central processing unit, and the evaluation coefficient is calculated through comprehensive analysis and compared with the reference coefficient.

9. A method for detecting the compressive strength of a corrugated cardboard box according to claim 8, characterized in that, Calculation and acquisition logic of the evaluation coefficient: Step One: The data monitored by the pressure sensor in real time is denoted as P; the data monitored by the distance sensor (19) in real time is denoted as D; the data monitored by the air pressure intensity sensor (18) in real time is denoted as A. Step Two: Calculation formula for the evaluation coefficient E: ， In the formula, , and are weighting coefficients, and . The determination of the weights can be obtained by conducting multiple experiments and analyzing the correlation degree between the data of each sensor and the actual damage condition of the carton. Among them, is the predicted maximum pressure value measured when the carton is completely damaged; is the maximum distance value measured by the predicted distance sensor when the sliding plate offsets to the limit position; is the maximum air pressure intensity value measured by the air pressure intensity sensor when the carton is not damaged. Step Three: Analyze the evaluation coefficient E and the reference coefficient: If E is greater than the reference coefficient, it indicates that the cardboard box is damaged. If E is less than the reference coefficient, the cardboard box is still within the normal use range.

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