Automatic deviation rectifying mechanism and method for bag making machine

Abstract

The invention discloses an automatic deviation rectifying mechanism and method for a bag making machine, and belongs to the technical field of packaging machinery. Comprising a rack, a detection unit, a driving unit, a deviation rectifying roller assembly and a control unit. The detection unit comprises an ultrasonic electric eye and a height adjusting assembly, the ultrasonic electric eye is installed on the rack through the height adjusting assembly, and the ultrasonic electric eye is located on the side of a material film and used for detecting the edge position of the material film in real time; the driving unit is installed on the machine frame, the output end of the driving unit is fixedly connected with the deviation rectifying roller assembly, and a material film penetrates through the deviation rectifying roller assembly to form 90-degree bending conveying. The control unit is electrically connected with the detection unit and the driving unit, and the control unit controls the driving unit to drive the deviation rectifying roller assembly to move transversely according to a real-time detection signal of the ultrasonic electric eye. The system has the advantages of being fast in response, high in precision, high in universality and the like, and the bag making efficiency and the product quality can be remarkably improved.

Description

Technical Field

[0001] The present invention relates to the technical field of packaging machinery, and particularly relates to an automatic deviation correction mechanism and method for a bag making machine. Background Art

[0002] A bag making machine is a core device in the packaging industry, which produces plastic bags through steps such as continuous feeding, heat sealing, and cutting. However, during high-speed operation, the film is prone to shift due to uneven tension or mechanical vibration, resulting in problems such as inconsistent sizes of finished bags and misaligned patterns.

[0003] In the prior art, a manual adjustment deviation correction device is mostly used to adjust the position of the film through a screw and a handle. However, manual operation has low efficiency, slow response speed, and cannot adapt to dynamic deviation in real time, seriously affecting production efficiency and product quality. Therefore, there is an urgent need for a mechanism that can detect and automatically correct film deviation in real time. Summary of the Invention

[0004] The present invention provides an automatic deviation correction mechanism and method for a bag making machine, which can solve the problems of low efficiency, slow response speed, and inability to adapt to dynamic deviation in real time existing in the manual adjustment deviation correction device in the prior art.

[0005] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] An automatic deviation correction mechanism for a bag making machine includes:

[0007] A frame;

[0008] A detection unit, the detection unit includes an ultrasonic electric eye and a height adjustment component. The ultrasonic electric eye is installed on the frame through the height adjustment component, and the ultrasonic electric eye is located on the side of the film for real-time detection of the edge position of the film;

[0009] A driving unit and a deviation correction roller assembly. The driving unit is installed on the frame, and the output end of the driving unit is fixedly connected to the deviation correction roller assembly. The film passes through the deviation correction roller assembly to form a 90° bending conveyance;

[0010] A control unit, the control unit is electrically connected to the detection unit and the driving unit respectively. The control unit controls the driving unit to drive the deviation correction roller assembly to move horizontally according to the real-time detection signal of the ultrasonic electric eye.

[0011] As a further scheme of the present invention: The driving unit includes:

[0012] A C-shaped bracket, the C-shaped bracket is fixedly installed on one side of the frame;

[0013] A permanent magnet motor, which is fixedly installed on the end plate on the side of the C-shaped bracket away from the frame;

[0014] A ball screw, one end of which is fixedly connected to the output shaft of the permanent magnet motor, and the ball screw is rotationally connected to the deviation rectifying roller assembly.

[0015] As a further scheme of the present invention: the deviation rectifying roller assembly includes:

[0016] A deviation rectifying base, which is slidably arranged between the two slide rods of the C-shaped bracket, and the ball screw rotates through the deviation rectifying base;

[0017] A deviation rectifying plate, which is obliquely and fixedly installed on the deviation rectifying base;

[0018] A deviation rectifying roller body, which is mounted on the deviation rectifying plate.

[0019] As a further scheme of the present invention: one end of the deviation rectifying plate is provided with an arc-shaped waist hole, and one end of the deviation rectifying roller body is detachably installed on the arc-shaped waist hole through a positioning pin.

[0020] As a further scheme of the present invention: the height adjustment assembly includes:

[0021] A positioning plate, which is fixedly installed on the top of the frame;

[0022] A limit sleeve, which is fixedly installed on the side of the frame;

[0023] An adjustment rod, which is movably inserted between the positioning plate and the limit sleeve, and the ultrasonic electric eye is installed on the adjustment rod;

[0024] A locking screw, one end of which is connected to the adjustment rod through a connecting plate, and the other end of the locking screw is screwed to the positioning plate.

[0025] As a further scheme of the present invention: the height adjustment assembly further includes an adjustment block, one end of which is slidably sleeved on the adjustment rod, the other end of the adjustment block is fixedly connected to the ultrasonic electric eye, and the adjustment block is fixed to the adjustment rod through a locking screw.

[0026] As a further scheme of the present invention: the control unit is a PLC controller, which receives the real-time detection signal of the ultrasonic electric eye, calculates the deviation value and then outputs a control signal to the drive unit.

[0027] As a further scheme of the present invention: the detection frequency of the ultrasonic electric eye is 10 - 50 kHz, and the detection accuracy is ±0.1 mm.

[0028] As a further solution of the present invention: the output end of the permanent magnet motor is directly connected to the ball screw through a coupling, and an encoder is built in the permanent magnet motor to form a closed-loop control system with the control unit.

[0029] The present invention also provides an automatic deviation correction method for the bottom compensation of a bag making machine, which is implemented by using the automatic deviation correction mechanism for a bag making machine, and includes the following steps: the ultrasonic electric eye continuously detects the edge position of the material film. When deviation is detected, the control unit calculates the deviation value and outputs a control signal to control the driving unit to drive the deviation correction roller assembly to move horizontally to the target position, so that the material film returns to the center line.

[0030] The beneficial effects of the present invention:

[0031] Through the coordinated cooperation of the detection unit, driving unit, deviation correction roller assembly and control unit of the automatic deviation correction mechanism of the present invention, during the operation of the bag making machine, the ultrasonic electric eye continuously detects the edge position of the material film. When deviation is detected, the control unit calculates the deviation value and outputs a control signal. The control unit calculates the deviation value and outputs a control signal to control the driving unit to drive the deviation correction roller assembly to move horizontally to the target position, so that the material film returns to the center line. The whole process does not require manual intervention, and the response time is less than 50 ms, ensuring stability under high-speed production; compared with the traditional manual adjustment of deviation correction, it can be more rapid and labor-saving, greatly improving the working efficiency. Compared with the manual adjustment of deviation correction, the automatic deviation correction can provide instant adjustment according to real-time subtle changes, realizing the full-automatic process of "detection - feedback - adjustment". Description of the Drawings

[0032] The following further describes the present invention with reference to the drawings.

[0033] Figure 1 It is a schematic structural diagram of an automatic deviation correction mechanism for a bag making machine of the present invention;

[0034] Figure 2 It is a partial structural schematic diagram of an automatic deviation correction mechanism for a bag making machine of the present invention;

[0035] Figure 3 It is a schematic structural diagram of the deviation correction roller assembly of the present invention;

[0036] Figure 4 It is Figure 3 The enlarged schematic diagram of the structure at A in

[0037] In the figure: 1, frame; 2, detection unit; 21, ultrasonic electric eye; 22, positioning plate; 23, limit sleeve; 24, adjusting rod; 25, locking screw; 26, adjusting block; 27, locking screw; 3, driving unit; 31, C-shaped bracket; 32, permanent magnet motor; 33, ball screw; 34, coupling; 4, deviation rectifying roller assembly; 41, deviation rectifying base; 42, deviation rectifying plate; 43, deviation rectifying roller body; 44, arc-shaped long hole. Detailed implementation manners

[0038] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Apparently, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without making creative efforts shall fall within the protection scope of the present invention.

[0039] In the description of the present invention, it should be understood that the terms "upper", "lower", "left", "right", "front", "rear", etc. indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, specific orientation structure and operation. Therefore, it should not be construed as a limitation of the present invention.

[0040] In addition, unless otherwise clearly defined and limited, the terms "installation", "connection", "connection", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the internal communication of two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0041] Please refer to Figures 1-4 As shown, the embodiment of the present invention provides an automatic deviation rectifying mechanism for a bag making machine, including a frame 1, a detection unit 2, a driving unit 3, a deviation rectifying roller assembly 4 and a control unit.

[0042] Please refer to Figure 1As shown, the detection unit 2 includes an ultrasonic electric eye 21 and a height adjustment component. The ultrasonic electric eye 21 is installed on the frame 1 through the height adjustment component. The ultrasonic electric eye 21 is located on the side of the material film. The ultrasonic electric eye 21 is used to detect the edge position of the material film in the operation of the bag making machine in real time, obtain the deviation data through non-contact measurement, and transmit the signal to the control unit to trigger the drive unit 3 to perform the deviation correction action. The drive unit 3 is installed on the frame 1, and the output end of the drive unit 3 is fixedly connected to the deviation correction roller assembly 4. When in use, the material film passes through the deviation correction roller assembly 4 to form a 90° bend and is transported through the ultrasonic electric eye 21. The ultrasonic electric eye 21 detects the edge position of the material film in the operation of the bag making machine in real time. The control unit (not shown in the figure) is electrically connected to the detection unit 2 and the drive unit 3 respectively. The control unit can be a PLC controller, which receives the real-time detection signal of the ultrasonic electric eye 21 and calculates the deviation value and then outputs the control signal to the drive unit 3, and controls the drive unit 3 to drive the deviation correction roller assembly 4 to move horizontally.

[0043] When the bag making machine is running, the ultrasonic electric eye 21 continuously detects the edge position of the material film. When a deviation is detected, the control unit calculates the deviation value and outputs a control signal to control the drive unit 3 to drive the deviation correction roller assembly 4 to move horizontally to the target position, so that the material film returns to the center line. The whole process does not require manual intervention, and the response time is less than 50ms, ensuring stability under high-speed production.

[0044] See also Figure 1 As shown, in this embodiment, the drive unit 3 includes a 匚-shaped bracket 31, a permanent magnet motor 32 and a ball screw 33. The 匚-shaped bracket 31 is fixedly mounted on one side of the frame 1 to play a supporting and connecting role. The permanent magnet motor 32 is fixedly mounted on the end plate of the 匚-shaped bracket 31 away from the side of the frame 1; one end of the ball screw 33 is fixedly connected to the output shaft of the permanent magnet motor 32, and the ball screw 33 is rotatably connected to the deviation correction roller assembly 4. The permanent magnet motor 32 is preferably a servo permanent magnet synchronous motor. The permanent magnet motor 32 is directly connected to the ball screw 33 through a coupling 34, omitting the deceleration mechanism in the traditional transmission chain, reducing the mechanical clearance, improving the transmission accuracy, and the repeat positioning accuracy is ≤0.01mm. The permanent magnet motor 32 has a built-in encoder, which forms a closed-loop control system with the control unit to achieve precise deviation correction. The PLC controller receives the offset signal of the ultrasonic electric eye 21 and generates a target position instruction. The permanent magnet motor 32 adjusts the speed and direction through the PID algorithm according to the real-time position feedback from the encoder, driving the ball screw 33 to drive the deviation correction roller assembly 4 to move horizontally to the set position. The high speed characteristics of the permanent magnet motor 32 cooperate with the lead of the ball screw 33 to achieve rapid fine-tuning of the deviation correction roller assembly 4, with a moving speed of ≥50mm / s. It is understandable that the permanent magnet motor 32 has a built-in temperature sensor and a current monitoring module, which triggers shutdown protection when the load is abnormal (such as torque exceeding the limit).

[0045] See alsoFigure 1 and Figure 3 As shown in Figure 3 , in this embodiment, the deviation rectifying roller assembly 4 includes a deviation rectifying base 41, a deviation rectifying plate 42 and a deviation rectifying roller body 43. The deviation rectifying base 41 is slidably arranged between two slide bars of the C-shaped bracket 31, and the ball screw 33 rotatably penetrates through the deviation rectifying base 41. The rotation of the ball screw 33 can drive the deviation rectifying base 41 to move horizontally along the two slide bars of the C-shaped bracket 31. The deviation rectifying plate 42 is obliquely and fixedly installed on the deviation rectifying base 41 by bolts, and the deviation rectifying roller body 43 is mounted on the deviation rectifying plate 42. When the bag-making machine is running, the film enters the deviation rectifying roller body 43 vertically from the bottom, and then forms a 90° bend through the deviation rectifying roller body 43. Further, please refer to Figure 4 As shown in Figure 4 , an arc-shaped waist hole 44 is formed at one end of the deviation rectifying plate 42, and one end of the deviation rectifying roller body 43 is detachably installed on the arc-shaped waist hole 44 through a positioning pin. The design of the arc-shaped waist hole 44 facilitates the adjustment of the inclination angle of the deviation rectifying roller body 43.

[0046] During specific implementation, the permanent magnet motor 32 drives the ball screw 33 to rotate. The rotating ball screw 33 drives the deviation rectifying base 41 to move horizontally along the two slide bars of the C-shaped bracket 31, thereby driving the deviation rectifying roller body 43 to move horizontally. The horizontal movement of the deviation rectifying roller body 43 adjusts the position of the film passing through the deviation rectifying roller body 43, so that the film returns to the center line.

[0047] Please refer to Figure 1 and Figure 2 As shown in Figure 2 , in this embodiment, the height adjustment assembly includes a positioning plate 22, a limit sleeve 23, an adjustment rod 24 and a locking screw 25. The positioning plate 22 is fixedly installed on the top of the frame 1 by bolts, the limit sleeve 23 is fixedly installed on the side of the frame 1 by bolts, the adjustment rod 24 is movably inserted between the positioning plate 22 and the limit sleeve 23, the ultrasonic electric eye 21 is installed on the adjustment rod 24, one end of the locking screw 25 is connected to the adjustment rod 24 through a connecting plate, and the other end of the locking screw 25 is screwed to the positioning plate 22. Further, the height adjustment assembly further includes an adjustment block 26. One end of the adjustment block 26 is slidably sleeved on the adjustment rod 24, the other end of the adjustment block 26 is fixedly connected to the ultrasonic electric eye 21, and the adjustment block 26 and the adjustment rod 24 are fixed through a locking screw 27. The height adjustment assembly with such a structural setting can adjust the height position of the adjustment rod 24 and the position of the ultrasonic electric eye 21 on the adjustment rod 24 in real time to meet the deviation rectifying requirements of different specifications of films.

[0048] It should be noted that the ultrasonic electric eye 21 is based on the principle of ultrasonic pulse reflection. The transmitter of the ultrasonic electric eye 21 emits high-frequency ultrasonic waves (frequency range: 10 - 50 kHz) towards the edge of the film. The receiver of the ultrasonic electric eye 21 captures the reflected wave and calculates the time difference, and obtains the offset of the film from the reference position through the formula D = v·t / 2 (where v is the speed of sound and t is the time difference). The detection frequency of the ultrasonic electric eye 21 is 10 - 50 kHz, and the detection accuracy is ±0.1 mm, which meets the real-time deviation correction requirements of high-speed bag-making machines (speed ≥ 200 m / min). The ultrasonic electric eye 21 has a built-in filtering algorithm, which can shield false signals caused by mechanical vibration or environmental noise, ensuring the reliability of detection. The ultrasonic electric eye 21 outputs a 4 - 20 mA analog signal to the control unit, and the control unit generates a deviation correction instruction according to a preset threshold (such as offset ≥ 0.5 mm). The response time from detection to the completion of the deviation correction action is ≤ 50 ms, avoiding batch defective products caused by cumulative offset of the film. It supports closed-loop control with the permanent magnet motor 32 and the ball screw 33, realizing a full-automatic process of "detection - feedback - adjustment".

[0049] The PLC controller uses the STM32F407 chip and has a built-in PID algorithm module. The parameter settings are as follows:

[0050] The proportional coefficient Kp = 0.8, the integral time Ti = 0.1 s, and the derivative time Td = 0.05 s;

[0051] The deviation correction frequency is set to 30 times per second, and the response time is ≤ 30 ms;

[0052] The human-machine interface supports inputting parameters such as the width and thickness of the film, and automatically matching the deviation correction amplitude.

[0053] An automatic deviation correction mechanism for a bag-making machine disclosed by the present invention can detect the edge position of the film in real time through the ultrasonic electric eye 21, and drive the permanent magnet motor 32 and the ball screw 33 by the PLC controller to adjust the lateral displacement of the deviation correction roller body 43, realizing high-speed and precise deviation correction. This automatic deviation correction mechanism has the advantages of fast response, high precision, and strong versatility, and can significantly improve the bag-making efficiency and product quality.

[0054] The automatic deviation correction mechanism of the present invention realizes the real-time detection and adjustment of the film position through the following steps:

[0055] Film edge detection

[0056] During the film transportation process, the ultrasonic electric eyes 21 symmetrically installed on both sides of the film continuously emit high-frequency pulse signals, and calculate the real-time position of the film edge through the time difference of receiving the reflected signals. The detection accuracy of the ultrasonic electric eye 21 is ±0.1 mm, and the sampling frequency is 100 Hz, ensuring the dynamic tracking ability for the high-speed moving film.

[0057] Offset calculation and control instruction generation

[0058] After the PLC controller receives the position signal transmitted by the ultrasonic electric eye 21, it calculates the deviation value between the actual position and the preset alignment position through the built-in PID control algorithm (proportional coefficient Kp = 0.8, integral time Ti = 0.1 s, derivative time Td = 0.05 s). If the deviation exceeds the threshold (default ±0.5 mm), the PLC controller generates a pulse width modulation (PWM) signal to drive the permanent magnet motor 32 to execute forward or reverse instructions.

[0059] Deviation correction execution and mechanical transmission

[0060] The permanent magnet motor 32 is directly connected to the ball screw 33 through the coupling 34, converting the rotational motion of the permanent magnet motor 32 into a linear motion. The lead of the ball screw 33 is 5 mm, the rated load is 500 N, and the response time ≤ 30 ms. When the permanent magnet motor 32 receives the control instruction, it drives the ball screw 33 to drive the deviation correction roller body 43 to move horizontally along the slide rod, thereby applying a horizontal thrust to the material film to correct its position deviation.

[0061] Closed-loop feedback and real-time calibration

[0062] The closed-loop feedback system is composed of the ultrasonic electric eye 21, the PLC controller, and the encoder of the permanent magnet motor 32. The encoder real-time feedbacks the rotational speed and position signals of the permanent magnet motor 32 to the PLC controller, forming a double closed-loop control (position loop + speed loop) with the detection data of the ultrasonic electric eye 21 to ensure the real-time performance and accuracy of the deviation correction action. The deviation correction frequency of the system is 30 times per second, and the dynamic deviation correction accuracy reaches ±0.2 mm. If the deviation still exceeds the threshold after 3 consecutive deviation corrections, the PLC controller triggers an alarm and stops the machine to avoid mechanical overload or material film tearing.

[0063] The above has described the preferred embodiments of the present invention in detail, and it cannot be considered as limiting the scope of implementation of the present invention. All equivalent changes and improvements made according to the scope of the present invention application shall still fall within the scope covered by the patent of the present invention.

Claims

1. An automatic deviation rectifying mechanism for a bag making machine, characterized in that, Comprising: A frame (1); A detection unit (2), the detection unit (2) includes an ultrasonic electric eye (21) and a height adjustment component. The ultrasonic electric eye (21) is mounted on the frame (1) through the height adjustment component. The ultrasonic electric eye (21) is located on the side of the material film and is used to detect the edge position of the material film in real time; A driving unit (3) and a deviation rectifying roller assembly (4). The driving unit (3) is mounted on the frame (1). The output end of the driving unit (3) is fixedly connected to the deviation rectifying roller assembly (4). The material film passes through the deviation rectifying roller assembly (4) to form a 90° bending conveyance; A control unit, the control unit is electrically connected to the detection unit (2) and the driving unit (3) respectively. The control unit controls the driving unit (3) to drive the deviation rectifying roller assembly (4) to move horizontally according to the real-time detection signal of the ultrasonic electric eye (21).

2. The automatic deviation rectifying mechanism for a bag making machine according to claim 1, characterized in that: The driving unit (3) includes: A U-shaped bracket (31), the U-shaped bracket (31) is fixedly installed on one side of the frame (1); A permanent magnet motor (32), the permanent magnet motor (32) is fixedly installed on the end plate of the U-shaped bracket (31) away from the frame (1); A ball screw (33), one end of the ball screw (33) is fixedly connected to the output shaft of the permanent magnet motor (32), and the ball screw (33) is rotationally connected to the deviation rectifying roller assembly (4).

3. The automatic deviation rectifying mechanism for a bag making machine according to claim 2, characterized in that: The deviation rectifying roller assembly (4) includes: A deviation rectifying base (41), the deviation rectifying base (41) is slidably arranged between the two slide bars of the U-shaped bracket (31), and the ball screw (33) rotatably penetrates through the deviation rectifying base (41); A deviation rectifying plate (42), the deviation rectifying plate (42) is obliquely and fixedly installed on the deviation rectifying base (41); A deviation rectifying roller body (43), the deviation rectifying roller body (43) is mounted on the deviation rectifying plate (42).

4. The automatic deviation rectifying mechanism for a bag making machine according to claim 3, wherein: One end of the deviation rectifying plate (42) is provided with an arc-shaped waist hole (44), and one end of the deviation rectifying roller body (43) is detachably installed on the arc-shaped waist hole (44) through a positioning pin.

5. The automatic deviation rectifying mechanism for a bag making machine according to claim 1, wherein: The height adjustment component includes: A positioning plate (22), the positioning plate (22) is fixedly installed on the top of the frame (1); A limit sleeve (23), the limit sleeve (23) is fixedly installed on the side of the frame (1); An adjustment rod (24), the adjustment rod (24) is movably inserted between the positioning plate (22) and the limit sleeve (23), and the ultrasonic electric eye (21) is installed on the adjustment rod (24); A locking screw (25), one end of the locking screw (25) is connected to the adjustment rod (24) through a connecting plate, and the other end of the locking screw (25) is screwed to the positioning plate (22).

6. The automatic deviation rectifying mechanism for a bag making machine according to claim 5, characterized in that: The height adjustment component further includes an adjustment block (26). One end of the adjustment block (26) is slidably sleeved on the adjustment rod (24), the other end of the adjustment block (26) is fixedly connected to the ultrasonic electric eye (21), and the adjustment block (26) is fixed to the adjustment rod (24) through a locking screw (27).

7. An automatic deviation rectifying mechanism for a bag making machine according to claim 1, characterized in that: The control unit is a PLC controller, which receives the real-time detection signal of the ultrasonic electric eye (21), calculates the deviation value, and then outputs a control signal to the drive unit (3).

8. The automatic deviation rectifying mechanism for a bag making machine according to claim 1, characterized in that: The detection frequency of the ultrasonic electric eye (21) is 10-50 kHz, and the detection accuracy is ±0.1 mm.

9. An automatic deviation rectifying mechanism for a bag making machine according to claim 2, characterized in that: The output end of the permanent magnet motor (32) is directly connected to the ball screw (33) via a coupling (34); the permanent magnet motor (32) has a built-in encoder, and forms a closed-loop control system with the control unit.

10. An automatic deviation rectification method for the bottom compensation of a bag-making machine, which is executed by using the automatic deviation rectification mechanism for a bag-making machine described in any one of claims 1-9, characterized in that, The following steps are involved: The ultrasonic electric eye (21) continuously detects the edge position of the material film. When a deviation is detected, the control unit calculates the deviation value and outputs a control signal to control the drive unit (3) to drive the deviation correction roller assembly (4) to move laterally to the target position, so that the material film returns to the center line.

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