Sealing device

A sealing device, comprising:

• a bag conveying mechanism configured to convey packaging bags;
• a sealing module configured to seal the opening of a packaging bag;
• and
• a module conveying mechanism configured to convey the sealing module so that the sealing module is moved synchronously with the packaging bag;
• wherein the sealing module is arranged above the packaging bag,
• wherein the sealing module comprises:
• a base and an actuator, and a first sealing block and a second sealing block arranged on the base,
• wherein the base is arranged on the module conveying mechanism, the first sealing block being hinged to the base, and a clamping opening being arranged between the first sealing block and the second sealing block,
• wherein the actuator is configured to open and close the clamping opening,
• wherein the actuator comprises a push rod and a horizontal actuation track, the push rod being horizontally slidably arranged on the base, a gear transmission structure being arranged between the push rod and the first sealing block, the push rod driving the first sealing block to swing via the gear transmission structure, and thereby the clamping opening is opened or closed,
• wherein a horizontal guide post is arranged vertically on the push rod and slidably connected to the horizontal actuation track, and the horizontal actuation track is arranged along a conveying path of the module conveying mechanism,
• wherein the sealing module is moved along the conveying path of the module conveying mechanism, the horizontal guide post sliding along the horizontal actuation track, the horizontal actuation track driving the push rod via the horizontal guide post to move horizontally, and thereby the clamping opening is opened or closed,
• wherein the push rod is perpendicular to the conveying path of the module conveying mechanism,
• wherein, in a projection on the horizontal plane, the distance between the horizontal actuation track and the module conveying mechanism is a horizontal control distance,
• wherein the size of the clamping opening is controlled by adjusting the horizontal control distance,
• wherein, according to the horizontal control distance, the horizontal actuation track comprises a wider track section and a narrower track section,
• wherein the clamping opening is opened when the sealing module travels on the wider track section,
• wherein the clamping opening is closed when the sealing module travels on the narrower track section,
• wherein, a transition track section is arranged between the wider track section and the narrower track section;
• or the wider track section and the narrower track section are separated from each other, and a track switching device is arranged between the wider track section and the narrower track section, the track switching device comprises a spur gear and a gear driving device, and the push rod is provided with a toothed rack structure meshed with the spur gear;
• in a process that the sealing module is conveyed, the gear driving device pushes the push rod to slide horizontally via the spur gear and the toothed rack structure, and, as the open/close state of the clamping opening is changed, the distance between the horizontal guide post and the module conveying mechanism is adjusted, and thereby transition between the wider track section and the narrower track section is realized,
• wherein the first sealing block and the second sealing block are respectively provided with a heating block configured to heating up and sealing an opening part of the packaging bag on one side of the clamping opening, and the heating blocks are connected to a power supply unit,
• wherein the first sealing block and the second sealing block are respectively provided with a soft sealing strip comprised of an elastic material on one side of the clamping opening, and wherein the first sealing block and the second sealing block clamp the packaging bag via the soft sealing strips,
• wherein the sealing device further comprises a vacuum pumping and nitrogen charging module configured to perform vacuum pumping and nitrogen charging for the packaging bag,
• wherein the vacuum pumping and nitrogen charging module comprises an air extraction and gas charging tube and a vertical actuation track, the air extraction and gas charging tube being arranged on the push rod in a way that it can slide up and down, and being connected to a vacuum generator and a nitrogen source respectively,
• wherein the air extraction and gas charging tube extend into the packaging bag for vacuum pumping and nitrogen charging for the packaging bag when it is moved downward,
• wherein the vertical actuation track is arranged along the horizontal actuation track, the air extraction and gas charging tube being provided with a vertical guide post slidably connected to the vertical actuation track, and
• wherein the sealing module is moved along the conveying path of the module conveying mechanism, the vertical guide post sliding along the vertical actuation track, the vertical actuation track driving the air extraction and gas charging tube to move up and down via the vertical guide post, and thereby the air extraction and gas charging tube extends into the packaging bag or retracts out of the packaging bag.