Barcode printing quality online detection system

Abstract

The invention discloses an online detection system for barcode printing quality, comprising a main control system unit, an imaging system unit, a winding servo unit, a fixed roller, a floating roller, a pressure roller mechanism, a bottom plate, a vertical plate and a cabinet; the main control system unit comprises an industrial computer, a display, a PLC controller, a photoelectric sensor, a power supply and distribution unit, a switch and an indicator light, an alarm, an upper limit sensor, and a lower limit sensor; the PLC controller is respectively connected with the photoelectric sensor, the switch and an indicator light, an alarm, an upper limit sensor, a lower limit sensor, an imaging system unit, and a winding servo unit, the imaging system unit is connected with the industrial computer, and the winding servo unit is connected with the industrial computer. The invention can realize the barcode online high-speed, high-precision, high-accuracy full inspection and the barcode jump code and repeated code database mark storage and data retrieval functions, reduce equipment investment, avoid rewinding and derivative problems, improve detection efficiency, and enhance the intelligent level in the field of barcode detection.

Description

Technical Field

[0001] The invention belongs to the technical field of barcode detection, and relates to an online detection system for barcode printing quality. Background Art

[0002] With the gradual improvement of the level of intelligence, barcodes have been widely used in various production management fields due to their economical and convenient advantages. Many companies use barcodes with poor printing quality on their products, which leads to serious problems such as product assembly errors and delivery errors. It is particularly important to test the quality of printed barcodes. Manual inspection can no longer meet the production needs of large-scale full inspection. The offline inspection equipment on the market has shortcomings such as barcode rewinding.

[0003] Offline testing equipment can achieve high-speed testing and ensure testing consistency, but there is a barcode rewinding process, which can easily cause secondary damage such as barcode shedding and adhesion. Installing it again on offline testing equipment for testing will also increase the workload and cause problems such as low work efficiency. The problem of skipping and duplication of printed barcodes is also one of the existing problems, which seriously affects the testing and use of production sites. Summary of the invention

[0004] The purpose of the present invention is to provide a barcode printing quality online detection system to solve the problem that the barcode cannot be monitored online and the offline equipment cannot be rewound.

[0005] The technical solution adopted by the present invention is a barcode printing quality online detection system, comprising a main control system unit, an imaging system unit, a winding servo unit, a fixed roller, a floating roller, a pressure roller mechanism, a bottom plate, a vertical plate and a cabinet; the main control system unit comprises an industrial computer, a display, a PLC controller, a photoelectric sensor, a power supply and distribution unit, a switch and an indicator light, an alarm, an upper limit sensor, and a lower limit sensor; the PLC controller is respectively connected to the photoelectric sensor, the switch and the indicator light, the alarm, the upper limit sensor, the lower limit sensor, the imaging system unit, and the winding servo unit, the imaging system unit is connected to the industrial computer and the display in sequence, and the winding servo unit is connected to the industrial computer; the imaging system unit comprises a camera and a lens, a light source controller, a light source, an imaging panel, a camera adjustment mechanism, and a light source adjustment mechanism; the camera and the lens are installed at the top of the cabinet through the camera adjustment mechanism, the light source adjustment mechanism is arranged below the camera and the lens and one end is connected to a light source, and an imaging panel is arranged in parallel below the light source; the winding servo unit comprises a servo driver, a servo motor, a reducer, a coupling, an expansion shaft, and a baffle.

[0006] The present invention is also characterized in that

[0007] The photoelectric sensor is arranged at one end of the imaging panel and is opposite to the light source adjustment mechanism. The pressure roller mechanism is arranged adjacent to the photoelectric sensor. There are two fixed rollers and they are symmetrically arranged at the bottom end of the light source adjustment mechanism and the outside of the pressure roller mechanism. A floating roller is arranged between the pressure roller mechanism and the fixed roller at the end. The upper limit sensor and the lower limit sensor are respectively arranged at the top and bottom of the floating roller.

[0008] Further, the servo driver is mounted on the base plate through fasteners, the servo motor is connected to the reducer through fasteners, the reducer is connected to the expansion shaft through a coupling using fasteners, and the baffle is connected to the expansion shaft through fasteners;

[0009] Furthermore, the display, switch, indicator light and alarm are installed on the front of the cabinet, and the PLC controller is installed on the vertical plate by fastening screws and structural parts;

[0010] Furthermore, the PLC controller is connected to a power supply and distribution unit, the power supply and distribution unit is connected to a light source controller, and the light source controller is connected to the light source.

[0011] The present invention can realize online high-speed, high-precision and high-accuracy full inspection of barcodes, and realize the printed barcode skipping and repeated code database mark storage and data retrieval functions. It has good versatility, can effectively reduce equipment investment, avoid rewinding and derivative problems, greatly improve detection efficiency, and enhance the level of intelligence in the field of barcode detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic diagram of the barcode printing quality online detection system of the present invention.

[0013] Figure 2 It is a front schematic diagram of the barcode printing quality online detection system of the present invention.

[0014] Figure 3 This is a front side internal structure diagram of the barcode printing quality online detection system of the present invention.

[0015] Figure 4 This is a diagram of the internal structure of the back side of the barcode printing quality online detection system of the present invention.

[0016] In the figure: 1. Main control system unit, 1-1. Industrial computer, 1-2. Display, 1-3. PLC controller (including lower computer software), 1-4. Photoelectric sensor, 1-5. Power supply and distribution unit, 1-6. Switch (with built-in indicator light), 1-7. Alarm, 1-8. Upper limit sensor, 1-9. Lower limit sensor; 2. Imaging system unit, 2-1. Camera and lens, 2-2. Light source controller, 2-3. Light source, 2-4. Imaging panel, 2-5. Camera adjustment mechanism, 2-6. Light source adjustment mechanism; 3. Winding servo system unit, 3-1. Servo driver, 3-2. Servo motor, 3-3. Reducer, 3-4. Coupling, 3-5. Expansion shaft, 3-6. Baffle; 4. Fixed roller; 5. Floating roller; 6. Pressing roller mechanism; 7. Bottom plate; 8. Vertical plate; 9. Cabinet. DETAILED DESCRIPTION

[0017] The technical solution of the present invention is clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0018] like Figure 1-Figure 4 As shown, the present invention includes a main control system unit 1, an imaging system unit 2, a winding servo unit 3, a fixed roller 4, a floating roller 5, a pressure roller mechanism 6, a bottom plate 7, a vertical plate 8 and a cabinet 9; the main control system unit 1 includes an industrial computer 1-1, a display 1-2, a PLC controller 1-3, a photoelectric sensor 1-4, a power supply and distribution unit 1-5, a switch and an indicator light 1-6, an alarm 1-7, an upper limit sensor 1-8, and a lower limit sensor 1-9, and the industrial computer 1-1 contains a host computer software; the PLC controller 1-3 is connected to the photoelectric sensor 1-4, the switch and the indicator light 1-6, the alarm 1-7, the upper limit sensor 1-8, the lower limit sensor 1-9, the imaging system unit 2, and the winding servo unit 3 through a digital input interface and a digital output interface, and the imaging system unit 2 is connected to the industrial computer 1-1 through a communication network port. 3 is connected to the industrial computer 1-1 through a communication interface; the PLC controller 1-3 is connected to the industrial computer 1-1 through a communication interface; the imaging system unit 2 includes a camera and lens 2-1, a light source controller 2-2, a light source 2-3, an imaging panel 2-4, a camera adjustment mechanism 2-5, and a light source adjustment mechanism 2-6; the camera and lens 2-1 are installed on the top of the cabinet 9 through the camera adjustment mechanism 2-5, the light source adjustment mechanism 2-6 is arranged below the camera and lens 2-1 and one end is connected to the light source 2-3, and an imaging panel 2-4 is arranged in parallel below the light source 2-3; the light source controller 2-2 is connected to the light source 2-3, and the brightness of the light source is adjusted by adjusting the output voltage of the light source controller 2-2; the winding servo unit 3 includes a servo driver 3-1, a servo motor 3-2, a reducer 3-3, a coupling 3-4, an expansion shaft 3-5, and a baffle 3-6.

[0019] The photoelectric sensor 1-4 is arranged at one end of the imaging panel 2-4 and is opposite to the light source adjustment mechanism 2-6. The pressure roller mechanism 6 is arranged adjacent to the photoelectric sensor 1-4. There are two fixed rollers 4 and they are symmetrically arranged at the bottom end of the light source adjustment mechanism 2-6 and the outside of the pressure roller mechanism 6. A floating roller 5 is arranged between the pressure roller mechanism 6 and the fixed roller 4 at the end. The upper limit sensor 1-8 and the lower limit sensor 1-9 are respectively arranged at the top and bottom of the floating roller 5.

[0020] The servo driver 3-1 is mounted on the base plate 7 through fasteners, the servo motor 3-2 is connected to the reducer 3-3 through fasteners, the reducer 3-3 is connected to the expansion shaft 3-5 through the coupling 3-4 using fasteners, and the baffle 3-6 is connected to the expansion shaft 3-5 through fasteners;

[0021] The display 1-2, the switch and indicator light 1-6, and the alarm 1-7 are installed on the front of the cabinet 9, and the PLC controller 1-3 is installed on the vertical plate 8 by fastening screws and structural parts;

[0022] The PLC controller 1-3 is connected to the power supply and distribution unit 1-5, the power supply and distribution unit 1-5 is connected to the light source controller 2-2, and the light source controller 2-2 is connected to the light source 2-3.

[0023] In the main control system unit 1 of the present invention, the power supply and distribution unit 1-5 supplies power to the camera and lens 2-1 and the light source controller 2-2 in the imaging system unit 2, and the PLC controller (including the lower computer software) 1-3 sends a signal through the digital output interface to realize the trigger control of the camera and lens 2-1 in the imaging system unit 2 according to the counting of the barcode by the photoelectric sensor 1-4, and realizes image acquisition. The camera and lens 2-1 further send the acquired image to the industrial computer 1-1 to realize image processing detection. In the main control system unit 1, the PLC controller (including the lower computer software) 1-3 controls the winding servo system unit 3 to realize the winding action of the barcode, specifically, the PLC controller (including the lower computer software) 1-3 sends a control signal to the servo driver 3-1 through the digital output interface, and the servo driver 3-1 further realizes the control of the servo motor 3-2, and according to the number of rotations of the servo motor 3-2 collected by the servo driver 3-1, the speed and torque of the servo motor 3-2 are controlled in sections, and finally the stable winding and subsequent detection of the barcode are realized.

[0024] The power supply and distribution unit 1-5 provides power for the entire system and has protection functions such as overcurrent. The switch and indicator light 1-6 complete the system start and stop, as well as the corresponding indication function. The alarm is used to alarm when the equipment detects unqualified products. The photoelectric sensor 1-4 is used to detect barcode counting. According to the group set by the industrial computer 1-1, the PLC controller (including the lower computer software) 1-3 further sends a signal through the digital output interface to control the camera 2-1 to collect dynamic images. The industrial computer 1-1 is used for image processing detection and judgment, and displays the detection results through the display 1-2. The display 1-2 is also used to detect production rules, group and other parameter settings, as well as different printing format barcode template learning settings. The upper limit sensor 1-8 and the lower limit sensor 1-9 are mainly used for the acceleration and deceleration control of winding, so that the floating roller can float within the position range of the upper limit sensor 1-8 and the lower limit sensor 1-9.

[0025] The camera adjustment mechanism 2-5 adjusts the imaging object distance between the camera and the lens 2-1 through its own vertical slide rail, and then locks it through its own locking wheel. The light source adjustment mechanism 2-6 adjusts the lighting angle and lighting horizontal position of the light source 2-3 through rotation adjustment and horizontal sliding adjustment of its own horizontal slide bar. The light source adjustment mechanism 2-6 adjusts the lighting height of the light source 2-3 through up and down sliding adjustment of its own vertical slide bar. After adjustment, it is locked through its own locking wheel, providing good imaging conditions for the camera and the lens 2-1 to capture images.

[0026] The servo motor 3-2 is connected to the reducer 3-3 by fasteners, the reducer 3-3 is connected to the expansion shaft 3-5 by fasteners through the coupling 3-4, and the baffle 3-6 is connected to the expansion shaft 3-5 by fasteners. The servo driver 3-1 realizes the motion control of the servo motor 3-2 according to the control setting and control logic of the industrial computer 1-1 and the PLC controller 1-3, and the baffle 3-6 is used to ensure that the side of the inspected barcode is rolled flat.

[0027] The fixed roller 4 is used to ensure the stability and linearity of the barcode being transmitted. The floating roller 5 uses its own weight to ensure that the barcode at the barcode printing end can be transmitted to the system, realize the barcode cache function and the transmission isolation from the barcode printing end, so as to ensure that the system rewinding the barcode does not affect the normal operation of the barcode printing end. The pressure roller mechanism generates a constant tension when the barcode is rewound to ensure the tightness and flatness of the barcode rewinding.

[0028] Combination Figures 1 to 4 The entire detection process when the present invention is used is described as follows:

[0029] First, the barcode printed by the printing end is passed through the right window of the cabinet to the right fixed roller 4, and then through the floating roller 5 to the pressing roller mechanism 6. The pressing roller mechanism is first loosened, and the barcode is pressed down after passing through (pressure is adjustable), and further fixed to the reel of the expansion shaft 3-5 through the photoelectric sensor 1-4, the imaging panel 2-4 and the left fixed roller 4. After installation, turn on the power, set the detection parameters on the upper computer software through the display 1-2, including the barcode increment and decrement production rules, barcode groups and each detection defect threshold and other parameters, start the operation, the photoelectric sensor 1-4 counts the number of each group of barcodes, and the PLC controller 1-3 triggers the camera 2-1 to collect images, and sends them to the industrial computer 1-1 for graphic processing detection and judgment, and outputs the judgment results. If the alarm function is enabled, the alarm 1-7 will alarm when unqualified products are detected.

[0030] During the entire working process, when the winding line speed does not match the barcode printing line speed, the floating roller 5 floats up and down to achieve automatic dynamic adjustment. When the barcode floats up to the upper limit sensor 1-8, it means that the winding line speed is greater than the printing line speed, and the system slows down the winding to prevent the winding servo system unit 2 from directly pulling the barcode being printed at the right printing end of the device and affecting the normal printing performance. When the barcode floats down to the lower limit sensor 1-9, it means that the winding line speed is less than the barcode printing line speed, and the system accelerates the winding to ensure that the barcode will not accumulate at the floating roller.

[0031] For barcodes with different printing formats (such as changes in group, font size, and printing information), the established font library collects qualified images to learn templates for each detection area of ​​each barcode. After the template learning is completed, it is saved and the barcode can be detected by importing the template later. Barcode defect detection is realized based on the key technologies of barcode black and white bar recognition and detection and barcode character recognition and detection, making the equipment highly versatile to meet various usage requirements.

[0032] Specific implementation method of online detection:

[0033] First, the following parameters are determined by measurement (all dimensions are in m): minimum roll diameter D1, maximum roll diameter D2, single-layer barcode thickness h, and further calculate the innermost layer circumference C1, outermost layer circumference C2, and the length change of each layer n. The barcode printing line speed V0 (unit: m / min), the reducer gear ratio K, and the target winding tension are set to F (unit: N). Then: the single-side layer thickness of the winding barcode Rolling layers

[0034] Based on the above parameters, the present invention proposes a segmented control implementation method for the motor winding speed and winding torque:

[0035] 1) Implementation method of motor winding speed segment control:

[0036] According to the formula:

[0037] The maximum motor speed (When the coil diameter is minimum)

[0038] Minimum motor speed (When the coil diameter is at maximum)

[0039] In order to achieve the best speed regulation effect, the speed regulation amount of each section is set to 1, then the number of segmented control is Vmax-Vmin, and the number of layers of further speed segmented control is:

[0040] Cn=N / (Vmax-Vmin). If it is not divisible evenly, just make a choice based on the size of the remainder.

[0041] 2) Implementation method of motor winding torque segment control:

[0042] According to the formula:

[0043] The maximum torque of the motor (When the coil diameter is at maximum)

[0044] Minimum motor torque (When the coil diameter is minimum)

[0045] In order to achieve the best speed regulation effect, the torque adjustment amount of each section is set to the torque value t corresponding to 1% of the servo rated torque. The number of layers of speed segment control is further:

[0046] Ct=N / (Tmax-Tmin), if it is not divisible, you can choose it according to the actual situation.

[0047] When the equipment is winding and running, the present invention proposes that the PLC collects the encoder signal of the servo motor through the servo driver, specifically collects the open collector Z phase pulse to realize the collection of the number of motor rotations Np. The circuit design is simple, and no high-speed counter is needed. The ordinary digital input terminal of the PLC can be used, and no complex pulse number calculation is required. The control logic of the PLC lower computer software is also relatively simple.

[0048] When the detected number of motor rotations Np is an integer multiple of Cn, the PLC calculates the current speed When the detected number of motor rotations Np is an integer multiple of Ct, the PLC calculates the current torque once

[0049] After each calculation of Vp and Tp is completed, the present invention proposes that the PLC sends the data to the industrial computer through a serial port or other communication method, and the industrial computer further sends the data to the servo driver through a serial port or other communication method to achieve dynamic control and adjustment of the motor running speed and torque, thereby ensuring the consistency of the winding line speed and the barcode printing line speed, the stability of the winding tension, and the winding torque are basically constant. The present invention does not discuss the transmission efficiency of the reducer, etc., and the motor torque can be further converted according to actual conditions.

[0050] The present invention is based on signal collection of the number of motor rotations, and does not use speed sensors and tension sensors for signal collection, thereby realizing open-loop control of motor speed and motor torque, ensuring that the winding line speed is basically matched with the barcode printing line speed, and the winding torque is basically stabilized to a fixed value, so that the online winding of the barcode is stable and reliable, laying a good foundation for image collection and subsequent detection.

[0051] The present invention designs a floating roller and a pressing roller mechanism. When the winding line speed does not match the barcode printing line speed, the floating roller floats up and down to achieve automatic dynamic adjustment, so as to prevent the barcode from piling up at the floating roller; at the same time, the winding process and the barcode printing end are well isolated. The pressing roller mechanism generates a tension on the surface of the transmitted barcode, so that the barcode is rolled densely and neatly, and the barcode at the imaging panel is ensured to be flat to achieve good image acquisition.

[0052] Barcode code skipping and re-code detection implementation method:

[0053] For barcode skipping and duplicate code detection, the conventional detection method is to directly alarm and shut down the machine, and the user intervenes to handle it. Otherwise, the subsequent barcode numbers will not meet the printing requirements. This processing method has low detection efficiency, especially for large-scale online detection of barcodes. The normal printing and detection efficiency of the barcodes is affected because the machine is shut down due to skipping and duplicate code processing.

[0054] The present invention proposes that when code skipping and duplication are detected, the group of barcodes is marked and stored using a database, and the previous group is marked and stored, indicating that code skipping and duplication exist between the two groups. At the same time, if the group of barcodes has no defects, it is a qualified product, and if there are defects, it is a defective product. It is further proposed to assign the number of the group of barcodes to the detection setting number to achieve continuous automatic detection without the need for human intervention. After the roll is printed and the detection is completed, it can be searched through the database to check whether there is code skipping and duplication in the entire roll. When the barcode is used, the skipping code can be supplemented and the duplicate code can be eliminated.

[0055] The present invention realizes good online winding of barcodes through open-loop control of motor speed and torque, combined with floating roller and pressure roller mechanism, realizes image acquisition and barcode defect detection, proposes and realizes code skipping and code repetition database tag storage and data retrieval, and has good engineering application value. The design architecture based on open-loop control has low cost and good cost competitive advantage.

[0056] The present invention proposes and realizes online detection, as well as print barcode skipping and re-code database mark storage and data retrieval functions, avoiding problems such as offline equipment rewinding links and can meet the technical requirements for large-scale online detection of barcodes.

[0057] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. Barcode printing quality online detection system, characterized by: It comprises a main control system unit (1), an imaging system unit (2), a winding servo unit (3), a fixed roller (4), a floating roller (5), a pressing roller mechanism (6), a bottom plate (7), a vertical plate (8) and a cabinet (9); The main control system unit (1) comprises an industrial computer (1-1), a display (1-2), a PLC controller (1-3), a photoelectric sensor (1-4), a power supply and distribution unit (1-5), a switch and an indicator light (1-6), an alarm (1-7), an upper limit sensor (1-8), and a lower limit sensor (1-9); the PLC controller (1-3) is respectively connected to the photoelectric sensor (1-4), the switch and an indicator light (1-6), the alarm (1-7), the upper limit sensor (1-8), the lower limit sensor (1-9), the imaging system unit (2), and the winding servo unit (3); the imaging system unit (2) is connected to the industrial computer (1-1), and the winding servo unit (3) is connected to the industrial computer (1-1); The imaging system unit (2) comprises a camera and lens (2-1), a light source controller (2-2), a light source (2-3), an imaging panel (2-4), a camera adjustment mechanism (2-5), and a light source adjustment mechanism (2-6); the camera and lens (2-1) are mounted on the top of the cabinet (9) via the camera adjustment mechanism (2-5); the light source adjustment mechanism (2-6) is arranged below the camera and lens (2-1) and has one end connected to the light source (2-3); and an imaging panel (2-4) is arranged below the light source (2-3) in parallel; The winding servo unit (3) comprises a servo driver (3-1), a servo motor (3-2), a reducer (3-3), a coupling (3-4), an expansion shaft (3-5), and a baffle (3-6); The rewinding servo unit (3) can dynamically adjust the speed and torque of the rewinding barcode under the control of the main control system unit (1), the steps are as follows: First, get the number of reel layers N of the reel barcode. , R is the thickness of one side of the rolled barcode, and h is the thickness of a single-layer barcode; Secondly, the number of intervals of speed segmented control is: Cn = N / (Vmax-Vmin); the number of intervals of torque segmented control is: Ct = N / (Tmax-Tmin); Vmax is the maximum motor speed corresponding to the minimum roll diameter D1 of the rolling barcode, and Vmin is the minimum motor speed corresponding to the maximum roll diameter D2 of the rolling barcode; Tmax is the maximum torque of the motor corresponding to the maximum roll diameter D2 of the rolled barcode, and Tmin is the minimum torque of the motor corresponding to the minimum roll diameter D1 of the rolled barcode; Third, when the winding servo unit (3) is running, the main control system unit (1) detects the number of rotations Np of the servo motor (3-2); When the number of rotations Np is an integer multiple of Cn, the current speed Vp = Vmax- 1; When the number of detected rotations Np is an integer multiple of Ct, the current torque Tp is obtained. ; Finally, the main control system unit (1) dynamically adjusts the speed and torque of the winding servo unit (3) through the obtained Vp and Tp.

2. The barcode printing quality online detection system according to claim 1 is characterized by: The photoelectric sensor (1-4) is arranged at one end of the imaging panel (2-4) and is opposite to the light source adjustment mechanism (2-6); the pressure roller mechanism (6) is arranged adjacent to the photoelectric sensor (1-4); there are two fixed rollers (4) which are symmetrically arranged at the bottom end of the light source adjustment mechanism (2-6) and outside the pressure roller mechanism (6); a floating roller (5) is arranged between the pressure roller mechanism (6) and the fixed roller (4) at the end; and the upper limit sensor (1-8) and the lower limit sensor (1-9) are arranged at the top and bottom of the floating roller (5), respectively.

3. The barcode printing quality online detection system according to claim 2 is characterized by: The servo drive (3-1) is mounted on a base plate (7) via fasteners, the servo motor (3-2) and the reducer (3-3) are connected via fasteners, the reducer (3-3) is connected to the expansion shaft (3-5) via a coupling (3-4) using fasteners, and the baffle (3-6) and the expansion shaft (3-5) are connected via fasteners.

4. The barcode printing quality online detection system according to claim 2 is characterized by: The display (1-2), switch and indicator light (1-6), and alarm (1-7) are mounted on the front of the cabinet (9), and the PLC controller (1-3) is mounted on the vertical plate (8) by means of fastening screws and structural parts.

5. The barcode printing quality online detection system according to claim 2 is characterized by: The PLC controller (1-3) is connected to a power supply and distribution unit (1-5), the power supply and distribution unit (1-5) is connected to a light source controller (2-2), and the light source controller (2-2) is connected to a light source (2-3).

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