Vacuum brick packaging system automatically adapting to changes in material density

Abstract

The application discloses a kind of automatic adaptation material density change's vacuum brick type packaging system, it includes quantitative weighing device, film roll bag device, brick type cavity device, PLC system, the weighing hopper of quantitative weighing device is equipped with material level detection switch, material level detection switch detects the material level height value in weighing hopper, the film roll bag device includes the film feeding drum with rotary encoder, the brick type cavity device includes cavity bottom plate, the lower end middle part of cavity bottom plate is connected with the upper end of air bag pneumatic cylinder, the lower end of air bag pneumatic cylinder is connected with cavity base, air bag pneumatic cylinder is connected with electromagnetic reversing valve, the lower end both sides of cavity bottom plate is also equipped with vibrator, the side plate upper end of the brick type cavity device is equipped with material detection switch, the PLC system is coordinated control to all devices in packaging system.The application can also make material surface height, bag mouth height keep consistency when material bulk density changes, improve the production efficiency and sealing property of vacuum sealing process.

Description

Technical Field

[0001] This invention discloses a vacuum brick-type packaging system that automatically adapts to changes in material density, belonging to the field of packaging machinery. Background Technology

[0002] Patent document CN201049743Y discloses a brick-shaped vacuum packaging machine with manual bagging method. The shaping mechanism shapes the bag filled with granular material into a cuboid (i.e., brick shape), and then the vacuuming mechanism and sealing mechanism complete the air extraction and heat sealing. The packaged finished product is brick-shaped, which facilitates subsequent stacking operations. Currently, most brick-type packaging machines use automatic film roll bag making and automatic bagging. In particular, with the development of the photovoltaic industry, vacuum brick-type packaging machines for granular polycrystalline silicon have been widely used. Due to the high cleanliness requirements of the packaging bags used for granular silicon, a single PE material is used, resulting in thicker, stiffer, and more expensive bags. Wrinkles at the bag opening can cause heat sealing failure and lead to air leakage. In addition, due to the influence of the granular silicon production process, the bulk density of granular silicon is constantly changing, causing the material level in the bag to fluctuate. The distance between the vacuum tube and the material level also changes accordingly. When the material level is high, the vacuum tube is prone to sucking away or clogging the vacuum tube, causing vacuum failure. When the material level is low, the vacuuming time will be longer, and the vacuum tube may also be blocked by the deformed bag opening, causing vacuum failure and reducing the production efficiency of the packaging machine. Summary of the Invention

[0003] To address the problems of long vacuuming time and vacuuming failure in existing vacuum brick packaging machines when the bulk density of granular materials changes, this invention proposes a vacuum brick packaging system that automatically adapts to changes in material density. It includes a quantitative weighing device 1, a film roll forming device 3, a brick-shaped cavity device 6, and a PLC system. The quantitative weighing device 1 has a material level detection switch 2 on its weighing hopper, which detects the material level height within the hopper. The film roll forming device 3 includes a film feeding roll 4 with a rotary encoder. The brick-shaped cavity device 6 includes a cavity bottom plate 8, the lower middle of which is connected to the upper end of an airbag cylinder 10. The lower end of the airbag cylinder 10 is connected to a cavity base 9. The airbag cylinder 10 is connected to an electromagnetic reversing valve 11. Vibrators 7 are also provided on both sides of the lower end of the cavity bottom plate 8. A material detection switch 5 is provided on the upper end of the side plate of the brick-shaped cavity device 6. The PLC system coordinates and controls all devices in the packaging system.

[0004] After each weighing is completed, the PLC system receives the material level height value from the material level detection switch 2 and calculates the difference C = material level height value - preset height value. Then, it controls the film roll bag making device 3 and the brick-shaped cavity device 6 according to the following rules:

[0005] (L1) If the difference C>0, the PLC system increases the number of rotations of the film feeding roll 4, so that the length of the empty bag A produced by the film roll bag making device 3 becomes longer according to the size of the difference C. After the material is filled into the brick-shaped cavity device 6 and the material is vibrated and compacted by the vibrator 7, the PLC system controls the electromagnetic reversing valve 11 to lower the cavity bottom plate 8 until the upper surface of the material is flush with the axis of the detection switch 5.

[0006] (L2) If the difference C < 0, the PLC system reduces the number of rotations of the film feeding roll 4, so that the length of the empty bag A produced by the film roll bag making device 3 becomes shorter according to the size of the difference C. After the material is filled into the brick-shaped cavity device 6 and the material is vibrated and compacted by the vibrator 7, the PLC system controls the electromagnetic reversing valve 11 to raise the cavity bottom plate 8 until the upper surface of the material is flush with the axis of the detection switch 5.

[0007] (L3) If the difference C=0, the PLC system keeps the number of rotations of the film feeding roll 4 at the preset value, and the length of the empty bag A produced by the film roll bag making device 3 is equal to the preset length value. At the same time, the PLC system keeps the cavity bottom plate 8 at the initial preset position.

[0008] The beneficial effects of this invention are:

[0009] (A) The material level height in the weighing hopper is measured by the material level detection switch 2. The change in this material level height represents the change in the material bulk density. The length of the empty bag A is appropriate according to the material level height. This can avoid the empty bag being too long and causing waste, and also avoid the empty bag being too short and affecting the subsequent vacuum sealing process.

[0010] (B) Adjust the lifting and lowering of the cavity bottom plate 8 according to the change of material bulk density (i.e. the size of the material level height value) so that the upper surface of the material inside the bag is aligned with the axis of the detection switch 5. This ensures that the distance between the upper surface of the material and the vacuum tube of the subsequent process remains consistent. This can prevent the granular material from clogging the vacuum tube and also prevent the vacuum tube from being blocked after the bag opening is deformed during vacuuming, thereby achieving a good, stable and consistent vacuuming effect.

[0011] (C) After the material bulk density changes, by adjusting the length of the empty bag A and the vertical position of the cavity bottom plate 8, when the brick-shaped cavity device 6 moves the material bag to the vacuum sealing position, the height distance between the upper end face of the bag opening and the heat sealing mechanism remains unchanged. This avoids the problem of the bag opening bending and deforming due to interference with other mechanisms caused by the bag opening being too high, thereby avoiding the problem of wrinkles at the heat sealing position causing air leakage. Attached Figure Description

[0012] Figure 1 This is a system composition and control principle diagram of the present invention. Detailed Implementation

[0013] For detailed embodiments of the present invention, please refer to Figure 1 A vacuum brick-type packaging system that automatically adapts to changes in material density includes a quantitative weighing device 1, a film roll bag-making device 3, a brick-type cavity device 6, and a PLC system. The quantitative weighing device 1 has a material level detection switch 2 on its weighing hopper, which detects the material level height in the weighing hopper. The film roll bag-making device 3 includes a film feeding roll 4 with a rotary encoder. The brick-type cavity device 6 includes a cavity bottom plate 8, the lower middle part of which is connected to the upper end of an airbag cylinder 10. The lower end of the airbag cylinder 10 is connected to a cavity base 9. The airbag cylinder 10 is connected to an electromagnetic reversing valve 11. Vibrators 7 are also provided on both sides of the lower end of the cavity bottom plate 8. A material detection switch 5 is provided on the upper part of the side plate of the brick-type cavity device 6. The PLC system coordinates and controls all devices in the packaging system.

[0014] After each weighing is completed, the PLC system receives the material level height value from the material level detection switch 2 and calculates the difference C = material level height value - preset height value. Then, it controls the film roll bag making device 3 and the brick-shaped cavity device 6 according to the following rules:

[0015] (L1) If the difference C>0, the PLC system increases the number of rotations of the film feeding roll 4, so that the length of the empty bag A produced by the film roll bag making device 3 becomes longer according to the size of the difference C. After the material is filled into the brick-shaped cavity device 6 and the material is vibrated and compacted by the vibrator 7, the PLC system controls the electromagnetic reversing valve 11 to lower the cavity bottom plate 8 until the upper surface of the material is flush with the axis of the detection switch 5.

[0016] (L2) If the difference C < 0, the PLC system reduces the number of rotations of the film feeding roll 4, so that the length of the empty bag A produced by the film roll bag making device 3 becomes shorter according to the size of the difference C. After the material is filled into the brick-shaped cavity device 6 and the material is vibrated and compacted by the vibrator 7, the PLC system controls the electromagnetic reversing valve 11 to raise the cavity bottom plate 8 until the upper surface of the material is flush with the axis of the detection switch 5.

[0017] (L3) If the difference C=0, the PLC system keeps the number of rotations of the film feeding roll 4 at the preset value, and the length of the empty bag A produced by the film roll bag making device 3 is equal to the preset length value. At the same time, the PLC system keeps the cavity bottom plate 8 at the initial preset position.

Claims

1. A vacuum brick-type packaging system that automatically adapts to changes in material density, comprising a quantitative weighing device (1), a film roll bag-making device (3), a brick-type cavity device (6), and a PLC system, characterized in that: The quantitative weighing device (1) is equipped with a material level detection switch (2) on the weighing hopper. The material level detection switch (2) detects the material level height value in the weighing hopper. The film roll bag making device (3) includes a film feeding roll (4) with a rotary encoder. The brick-shaped cavity device (6) includes a cavity bottom plate (8). The lower middle part of the cavity bottom plate (8) is connected to the upper end of the airbag cylinder (10). The lower end of the airbag cylinder (10) is connected to the cavity base (9). The airbag cylinder (10) is connected to the electromagnetic reversing valve (11). Vibrators (7) are also provided on both sides of the lower end of the cavity bottom plate (8). The upper part of the side plate of the brick-shaped cavity device (6) is equipped with a material detection switch (5). The PLC system coordinates and controls all devices in the packaging system. After each weighing is completed, the PLC system receives the material level height value from the material level detection switch (2), calculates the difference C = material level height value - preset height value, and then controls the film roll bag making device (3) and the brick-shaped cavity device (6) according to the following rules: (L1) If the difference C>0, the PLC system increases the number of rotations of the film feeding roll (4) so ​​that the length of the empty bag (A) produced by the film roll bag making device (3) becomes longer according to the size of the difference C. After the material is filled into the brick-shaped cavity device (6) and the material is vibrated and compacted by the vibrator (7), the PLC system controls the electromagnetic reversing valve (11) to lower the cavity bottom plate (8) until the upper surface of the material is flush with the axis of the detection switch (5). (L2) If the difference C < 0, the PLC system reduces the number of rotations of the film feeding roll (4) so ​​that the length of the empty bag (A) produced by the film roll bag making device (3) becomes shorter according to the size of the difference C. After the material is filled into the brick-shaped cavity device (6) and the material is vibrated and compacted by the vibrator (7), the PLC system controls the electromagnetic reversing valve (11) to raise the cavity bottom plate (8) until the upper surface of the material is flush with the axis of the detection switch (5). (L3) If the difference C=0, the PLC system keeps the number of rotations of the film feeding roll (4) unchanged at the preset value, and the length of the empty bag (A) produced by the film roll bag making device (3) is equal to the preset length value. At the same time, the PLC system keeps the cavity bottom plate (8) unchanged at the initial preset position.

Images