CN221024629U - Packaging box film sealing machine - Google Patents

Abstract

The utility model discloses a packaging box film sealing machine, which comprises: the conveying mechanism comprises a frame, a conveying belt and a first motor for driving the conveying belt to rotate; the edge sealing mechanism comprises an end sealing assembly and a side sealing assembly, wherein the end sealing assembly comprises two oppositely arranged first ironing plates and at least one first cylinder for driving the first ironing plates to be close to or far away from each other, the side sealing assembly comprises a bracket, a second ironing plate and a second cylinder for driving the second ironing plate to ascend or descend, and the second ironing plate is positioned above the conveying belt; thermoplastic mechanism, including the workstation, push away the box subassembly and thermoplastic the subassembly, thermoplastic the subassembly sets up the workstation, thermoplastic the subassembly includes that the third scalds board, fourth scalds the board, drive the fourth scalds the board is close to or keeps away from the third cylinder that the board was scalded to the third, push away the box subassembly with the packing carton push away the third scalds the board with the fourth scalds between the board. The utility model can enable the transparent film to be tightly attached to the surface of the packaging box.

Description

Packaging box film sealing machine

Technical Field

The utility model relates to the technical field of film sealing equipment, in particular to a packaging box film sealing machine.

Background

The transparent film three-dimensional packaging machine is mainly suitable for single-piece or multi-piece (integrated package) automatic outer packages of various box-shaped articles in the industries of medicines, foods, health-care products, tea, cosmetics, gifts, stationery, audio-visual products and the like, plays roles of anti-counterfeiting, dampproofing, dust prevention and the like, improves the grade of the products, and can also be provided with anti-counterfeiting easy-to-pull wires.

The existing film sealing equipment comprises a film coating mechanism, a film cutting mechanism, a folding mechanism, a film sealing mechanism and a conveying mechanism, wherein the film coating mechanism wraps the coiled transparent film on the outer surface of a packaging box, the film cutting mechanism cuts the coiled transparent film and the transparent film wrapped on the packaging box, the folding mechanism folds the transparent films at two ends of the packaging box, then the film sealing mechanism seals edges at the joints of the two ends of the packaging box and the transparent film, and finally the conveying mechanism conveys the packaged packaging box to the next procedure.

However, the existing film sealing mechanism only seals edges of two ends and one side edge of the packaging box wrapped with the transparent film, so that the transparent film cannot cling to the surface of the packaging box, and the packaging quality of products is affected.

Disclosure of utility model

The present utility model aims to solve at least one of the technical problems existing in the prior art. Therefore, the utility model provides a packaging box film sealing machine which can enable a transparent film to be tightly attached to the surface of a packaging box.

According to an embodiment of the utility model, a packaging box film sealing machine comprises: the conveying mechanism is used for conveying the packaging box wrapping the transparent film and comprises a frame, a conveying belt arranged on the frame and a first motor driving the conveying belt to rotate; the edge sealing mechanism is used for sealing edges of the transparent film wrapped on the packaging box and is arranged on the frame, and comprises an end sealing assembly and a side sealing assembly, wherein the end sealing assembly comprises two first ironing plates which are oppositely arranged, at least one first cylinder which drives the first ironing plates to be close to or far away from each other, the conveying belt is positioned between the two first ironing plates, the side sealing assembly comprises a support, a second ironing plate and a second cylinder which drives the second ironing plate to ascend or descend, the support is arranged on the frame, the second cylinder is arranged on the support, and the second ironing plate is positioned above the conveying belt; thermoplastic mechanism, including the workstation, push away the box subassembly and thermoplastic the subassembly, the workstation sets up frame one side, the workstation with the conveyer belt parallel and level, thermoplastic the subassembly sets up the workstation, thermoplastic the subassembly includes that the third scalds the board, the fourth scalds the board, drive the fourth scalds the board and is close to or keep away from the third cylinder that the board was scalded to the third, push away the box subassembly and push away the packing carton after the banding to the third scalds the board with between the board is scalded to the fourth.

The packaging box film sealing machine provided by the embodiment of the utility model has at least the following beneficial effects:

1. According to the utility model, the conveying mechanism is arranged, the packaging box wrapped with the transparent film is placed on the conveying belt, the conveying belt is driven by the first motor to rotate, and the conveying belt can drive the packaging box to automatically convey, so that the degree of automation is improved, and the labor intensity is reduced.

2. According to the utility model, the edge sealing mechanism is arranged, when the packaging box is conveyed between the two first ironing plates, the first ironing plates are driven by the at least one first cylinder to be close to the packaging box until the two first ironing plates are abutted against two ends of the packaging box, the transparent films at two ends of the packaging box are respectively edge-sealed by the two first ironing plates, then the first ironing plates are driven by the first cylinder to be far away from the packaging box, the packaging box is continuously conveyed to the position right below the second ironing plates by the conveying belt, at the moment, the second ironing plates are driven by the second cylinder to descend, and the edges of the transparent films at the side edges of the packaging box are sealed by the second ironing plates, so that all edge sealing of the transparent films can be realized, and the sealing performance of the transparent films is improved.

3. According to the utility model, the thermoplastic mechanism is arranged, when the conveyor belt conveys the sealed packaging box to one side of the box pushing assembly, the box pushing assembly pushes the sealed packaging box between the third ironing plate and the fourth ironing plate, the workbench is flush with the conveyor belt, the packaging box can be smoothly moved when pushed, the workbench can support the packaging box, then the third cylinder drives the fourth ironing plate to be close to the third ironing plate, the fourth ironing plate and the third ironing plate respectively heat the transparent films on two sides of the packaging box, and the transparent films undergo thermal shrinkage reaction after being heated, so that the transparent films can be tightly attached to the surface of the packaging box.

According to some embodiments of the utility model, the thermoplastic mechanism further comprises a baffle plate, the baffle plate is arranged on the frame, the baffle plate is used for blocking the packing boxes on the conveyor belt from moving, and the abutting surface of the baffle plate is flush with the working surface of the third ironing plate.

The beneficial effects are that: through setting up the baffle, when the packing carton was carried the baffle, the packing carton stayed in the butt face of baffle, the butt face of baffle and the working face parallel and level of third ironing board to, accurate location when can being convenient for promote the packing carton makes the packing carton can accurately push to the third ironing board and fourth ironing board between.

According to some embodiments of the utility model, the pushing assembly comprises a pushing plate, a fourth cylinder driving the pushing plate to move, and the pushing plate is used for pushing the packaging box blocked by the baffle plate.

The beneficial effects are that: through setting up push pedal and fourth cylinder, the packing carton is stayed behind the butt face of baffle, and fourth cylinder drive push pedal removes, and the push pedal promotes the packing carton and removes between third ironing board and the fourth ironing board, and the simple structure of fourth cylinder and push pedal easily realizes.

According to some embodiments of the utility model, the pushing box assembly further comprises a supporting plate, the supporting plate is arranged on the frame and the workbench, the baffle plate and the third ironing plate are fixed on one side of the supporting plate, the fourth air cylinder is fixed on the other side of the supporting plate, and the pushing plate is connected with the telescopic end of the fourth air cylinder through a connecting block.

The beneficial effects are that: through setting up the backup pad, the backup pad can support baffle, third scalds board and fourth cylinder, and moreover, the fourth cylinder sets up and keeps away from third in the backup pad and scalds board one side, can reduce the fourth cylinder on the length direction occupation space, makes the overall structure of equipment compact.

According to some embodiments of the utility model, a guide rail is arranged at the top of the supporting plate, the connecting block is slidably connected with the guide rail, and the guide rail is parallel to the baffle.

The beneficial effects are that: through setting up the guide rail, when fourth cylinder drives connecting block and push pedal and removes jointly, the connecting block can slide along the length direction of guide rail to, the guidance quality when can increasing the push pedal and remove, guarantee that the packing carton can accurately remove between third scalding plate and the fourth scalding plate.

According to some embodiments of the utility model, two first cylinders are provided, and the two first cylinders respectively drive the two first ironing plates to move.

The beneficial effects are that: through setting up two first cylinders, when the packing carton removes between two first ironing board, two first cylinders drive two first ironing board simultaneously relatively near respectively to, can make packing carton atress even, moreover, can improve production efficiency.

According to some embodiments of the utility model, the table is provided with a mounting plate for mounting the third cylinder.

The beneficial effects are that: through setting up the mounting panel, the mounting panel is used for installing the third cylinder to, the dismouting of the third cylinder of being convenient for.

According to some embodiments of the utility model, the fourth ironing plate is provided with a first guide rod, and the mounting plate is provided with a first guide hole for accommodating the first guide rod to pass through.

The beneficial effects are that: through setting up first guide bar and first guiding hole, when the third cylinder drive fourth scalds the board and removes, the fourth scalds the board and drives first guide bar and remove, and first guide bar slides through in first guiding hole to, can increase the guidance quality when the fourth scalds the board and remove.

According to some embodiments of the utility model, two first guide rods are provided, and the two first guide rods are respectively located at two sides of the third cylinder.

The beneficial effects are that: through making first guide bar be provided with two, two first guide bars are located the third cylinder both sides respectively, and when the third cylinder driven fourth scalded the board and remove, the fourth scalded the board and drives two first guide bars simultaneously and remove to, can prevent that the fourth from scalding the board and take place to warp, make the transparent film of parcel at the packing carton surface be heated evenly.

According to some embodiments of the utility model, the second ironing plate is provided with two second guide rods, the bracket is provided with two second guide holes, the two second guide rods respectively penetrate through the two second guide holes, and the two second guide rods are respectively positioned at two sides of the second cylinder.

The beneficial effects are that: through setting up two second guide bars and second guiding hole, when the second cylinder drove the second and scalds the board and remove, the second scalds the board and drives two second guide bars and remove, and two second guide bars remove along two second guiding holes respectively to, can increase the second and scald the guidance quality when the board removes, prevent that the second from scalding the board and take place to warp, guarantee that transparent film on the packing carton is heated evenly, guarantee the banding quality of packing carton.

Additional aspects and advantages of the utility model will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the utility model.

Drawings

The foregoing and/or additional aspects and advantages of the utility model will become apparent and may be better understood from the following description of embodiments taken in conjunction with the accompanying drawings in which:

Fig. 1 is a schematic structural view of a packaging box film sealing machine according to an embodiment of the present utility model;

FIG. 2 is a top view of FIG. 1;

fig. 3 is a side view of the edge banding mechanism of fig. 1.

Reference numerals: 100-conveying mechanism, 110-rack, 120-conveying belt, 130-first motor, 140-edge banding mechanism, 150-end packaging component, 160-side packaging component, 170-first ironing board, 180-first cylinder, 190-bracket, 200-second ironing board, 210-second cylinder, 220-thermoplastic mechanism, 230-workbench, 240-pushing box component, 250-thermoplastic component, 260-third ironing board, 270-fourth ironing board, 280-third cylinder, 290-baffle, 300-pushing plate, 310-fourth cylinder, 320-supporting board, 330-connecting block, 340-guide rail, 350-mounting plate, 360-first guide bar, 370-second guide bar.

Detailed Description

Embodiments of the present utility model are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative only and are not to be construed as limiting the utility model.

In the description of the present utility model, it should be understood that references to orientation descriptions such as upper, lower, front, rear, left, right, etc. are based on the orientation or positional relationship shown in the drawings, are merely for convenience of description of the present utility model and to simplify the description, and do not indicate or imply that the apparatus or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the present utility model.

In the description of the present utility model, a number means one or more, a number means two or more, and greater than, less than, exceeding, etc. are understood to not include the present number, and above, below, within, etc. are understood to include the present number. The description of the first and second is for the purpose of distinguishing between technical features only and should not be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

In the description of the present utility model, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.

A packaging box film sealing machine according to an embodiment of the present utility model is described below with reference to the accompanying drawings.

Referring to fig. 1 to 3, a film sealing machine for packaging boxes according to an embodiment of the present utility model includes a conveying mechanism 100, a sealing mechanism 140, and a thermoplastic mechanism 220.

Wherein, conveying mechanism 100 includes frame 110, sets up at the conveyer belt 120 of frame 110, the first motor 130 of drive conveyer belt 120 gyration, and the packing carton of parcel has the transparent film is placed on conveyer belt 120, and conveyer belt 120 can drive the packing carton and carry automatically to, improve degree of automation, reduce intensity of labour.

Functionally, the edge sealing mechanism 140 is used for sealing the edges of the transparent film wrapped on the packaging box.

Specifically, the edge sealing mechanism 140 is disposed on the frame 110, and includes an end packaging assembly 150 and a side packaging assembly 160, the end packaging assembly 150 includes two first ironing plates 170 disposed opposite to each other, at least one first cylinder 180 driving the first ironing plates 170 to approach or separate from each other, the conveyor belt 120 is disposed between the two first ironing plates 170, the side packaging assembly 160 includes a bracket 190, a second ironing plate 200, and a second cylinder 210 driving the second ironing plate 200 to ascend or descend, the bracket 190 is disposed on the frame 110, the second cylinder 210 is mounted on the bracket 190, and the second ironing plate 200 is disposed above the conveyor belt 120.

Further, the thermoplastic mechanism 220 includes a workbench 230, a box pushing assembly 240 and a thermoplastic assembly 250, the workbench 230 is disposed on one side of the frame 110, the workbench 230 is flush with the conveyor belt 120, the thermoplastic assembly 250 is disposed on the workbench 230, the thermoplastic assembly 250 includes a third ironing plate 260, a fourth ironing plate 270, and a third cylinder 280 driving the fourth ironing plate 270 to approach or separate from the third ironing plate 260, and the box pushing assembly 240 pushes the sealed package between the third ironing plate 260 and the fourth ironing plate 270.

In operation, the conveyor belt 120 conveys the package to between the two first ironing plates 170, at least one first cylinder 180 drives the first ironing plates 170 to approach the package until the two first ironing plates 170 are abutted against two ends of the package, the two first ironing plates 170 respectively seal edges of transparent films at two ends of the package, then the first cylinder 180 drives the first ironing plates 170 to be far away from the package, the conveyor belt 120 continues to convey the package to right below the second ironing plate 200, at this moment, the second cylinder 210 drives the second ironing plate 200 to descend, the second ironing plate 200 seals edges of transparent films at sides of the package, when the conveyor belt 120 conveys the sealed package to one side of the box pushing assembly 240, the box pushing assembly 240 pushes the sealed package to between the third ironing plate 260 and the fourth ironing plate 270, because the workbench 230 and the conveyor belt 120 can move smoothly when pushing the package, and the workbench 230 can support the package, then the third cylinder 280 drives the fourth ironing plate 270 to approach the third ironing plate 260, so that the fourth ironing plate 270 and the transparent films at two sides of the package are heated by the heat-shrinkable transparent films respectively.

Therefore, the utility model can enable the transparent film to be closely attached to the surface of the packaging box.

In some preferred embodiments, the thermoplastic mechanism 220 further includes a stop 290, the stop 290 being disposed on the frame 110, the stop 290 for stopping the movement of the cartons on the conveyor 120, the abutment surface of the stop 290 being flush with the working surface of the third ironing plate 260.

It can be appreciated that by providing the baffle 290, when the package is conveyed to the baffle 290, the package is stopped at the abutting surface of the baffle 290, and the abutting surface of the baffle 290 is flush with the working surface of the third ironing plate 260, so that the package can be conveniently and accurately positioned when being pushed, and the package can be accurately pushed between the third ironing plate 260 and the fourth ironing plate 270.

In some preferred embodiments, the pusher assembly 240 includes a pusher plate 300, a fourth cylinder 310 driving the pusher plate 300 to move, and the pusher plate 300 is used to push the package blocked by the barrier 290.

It can be appreciated that by arranging the push plate 300 and the fourth air cylinder 310, after the package box stays on the abutting surface of the baffle 290, the fourth air cylinder 310 drives the push plate 300 to move, and the push plate 300 pushes the package box to move between the third ironing plate 260 and the fourth ironing plate 270, so that the structure of the fourth air cylinder 310 and the push plate 300 is simple and easy to realize.

In some preferred embodiments, the pushing box assembly 240 further includes a support plate 320, the support plate 320 is disposed on the frame 110 and the table 230, the barrier 290 and the third ironing board 260 are fixed on one side of the support plate 320, the fourth air cylinder 310 is fixed on the other side of the support plate 320, and the pushing plate 300 is connected to the telescopic end of the fourth air cylinder 310 through a connection block 330.

It can be appreciated that by providing the support plate 320, the support plate 320 can support the baffle 290, the third ironing plate 260 and the fourth air cylinder 310, and the fourth air cylinder 310 is disposed at a side of the support plate 320 far from the third ironing plate 260, so that the space occupied in the length direction of the fourth air cylinder 310 can be reduced, and the overall structure of the apparatus is compact.

In some preferred embodiments, the top of the support plate 320 is provided with a guide rail 340, the connection block 330 is slidably connected to the guide rail 340, and the guide rail 340 is parallel to the barrier 290.

It can be appreciated that, by arranging the guide rail 340, when the fourth cylinder 310 drives the connecting block 330 and the push plate 300 to move together, the connecting block 330 can slide along the length direction of the guide rail 340, thereby increasing the guiding performance of the push plate 300 during moving, and ensuring that the packing box can accurately move between the third ironing plate 260 and the fourth ironing plate 270.

In some preferred embodiments, two first cylinders 180 are provided, and the two first cylinders 180 respectively drive the two first ironing plates 170 to move.

It can be appreciated that by providing two first cylinders 180, when the packing box moves between the two first ironing plates 170, the two first cylinders 180 respectively drive the two first ironing plates 170 to be relatively close together at the same time, so that the packing box can be uniformly stressed, and the production efficiency can be improved.

In some preferred embodiments, the table 230 is provided with a mounting plate 350, the mounting plate 350 being used to mount the third cylinder 280.

It will be appreciated that by providing the mounting plate 350, the mounting plate 350 is used to mount the third cylinder 280, thereby facilitating the removal and installation of the third cylinder 280.

In some preferred embodiments, the fourth ironing board 270 is provided with a first guide bar 360 and the mounting plate 350 is provided with a first guide hole for receiving the first guide bar 360 therethrough.

It can be appreciated that by providing the first guide bar 360 and the first guide hole, when the third cylinder 280 drives the fourth ironing plate 270 to move, the fourth ironing plate 270 drives the first guide bar 360 to move, and the first guide bar 360 slides through the first guide hole, thereby increasing the guiding property of the fourth ironing plate 270 when moving.

In some preferred embodiments, the first guide bars 360 are provided in two, and the two first guide bars 360 are located at both sides of the third cylinder 280, respectively.

It can be appreciated that by arranging two first guide rods 360, the two first guide rods 360 are respectively located at two sides of the third cylinder 280, and when the third cylinder 280 drives the fourth ironing plate 270 to move, the fourth ironing plate 270 simultaneously drives the two first guide rods 360 to move, so that the fourth ironing plate 270 can be prevented from being askew, and the transparent film wrapped on the outer surface of the packaging box is heated uniformly.

In some preferred embodiments, the second ironing board 200 is provided with two second guide bars 370, the bracket 190 is provided with two second guide holes, the two second guide bars 370 respectively pass through the two second guide holes, and the two second guide bars 370 are respectively located at both sides of the second cylinder 210.

It can be appreciated that by arranging the two second guide rods 370 and the second guide holes, when the second cylinder 210 drives the second ironing plate 200 to move, the second ironing plate 200 drives the two second guide rods 370 to move, and the two second guide rods 370 respectively move along the two second guide holes, thereby increasing the guiding performance of the second ironing plate 200 during moving, preventing the second ironing plate 200 from being skewed, ensuring that the transparent film on the packaging box is heated uniformly, and ensuring the edge sealing quality of the packaging box.

In the description of the present specification, reference to the terms "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the utility model. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The embodiments of the present utility model have been described in detail with reference to the accompanying drawings, but the present utility model is not limited to the above embodiments, and various changes can be made within the knowledge of one of ordinary skill in the art without departing from the spirit of the present utility model.

Claims (10)

1. A packaging box film sealing machine, which is characterized by comprising:

The conveying mechanism (100) is used for conveying the packaging box wrapping the transparent film and comprises a frame (110), a conveying belt (120) arranged on the frame (110) and a first motor (130) for driving the conveying belt (120) to rotate;

The edge sealing mechanism (140) is used for sealing edges of transparent films wrapped on the packaging box and is arranged on the frame (110), the edge sealing mechanism comprises an end sealing assembly (150) and a side edge sealing assembly (160), the end sealing assembly (150) comprises two oppositely arranged first ironing plates (170) and at least one first cylinder (180) for driving the first ironing plates (170) to be close to or far away from each other, the conveying belt (120) is arranged between the two first ironing plates (170), the side edge sealing assembly (160) comprises a support (190), a second ironing plate (200) and a second cylinder (210) for driving the second ironing plate (200) to ascend or descend, the support (190) is arranged on the frame (110), the second cylinder (210) is arranged on the support (190), and the second ironing plate (200) is arranged above the conveying belt (120).

Thermoplastic mechanism (220), including workstation (230), push away box subassembly (240) and thermoplastic subassembly (250), workstation (230) set up frame (110) one side, workstation (230) with conveyer belt (120) parallel and level, thermoplastic subassembly (250) set up workstation (230), thermoplastic subassembly (250) include third scalding plate (260), fourth scalding plate (270), drive fourth scalding plate (270) are close to or keep away from third cylinder (280) of third scalding plate (260), push away box subassembly (240) with the packing carton after the banding push away third scalding plate (260) with between fourth scalding plate (270).

2. The machine of claim 1, wherein the thermoplastic mechanism (220) further comprises a baffle (290), the baffle (290) is disposed on the frame (110), the baffle (290) is configured to block movement of the packages on the conveyor belt (120), and an abutment surface of the baffle (290) is flush with a working surface of the third ironing plate (260).

3. A packaging film sealing machine according to claim 2, wherein the box pushing assembly (240) comprises a push plate (300) and a fourth air cylinder (310) for driving the push plate (300) to move,

The push plate (300) is used for pushing the packing box blocked by the baffle plate (290).

4. A packaging box film sealing machine according to claim 3, wherein the box pushing assembly (240) further comprises a supporting plate (320), the supporting plate (320) is arranged on the frame (110) and the workbench (230), the baffle plate (290) and the third ironing plate (260) are fixed on one side of the supporting plate (320), the fourth air cylinder (310) is fixed on the other side of the supporting plate (320), and the pushing plate (300) is connected with the telescopic end of the fourth air cylinder (310) through a connecting block (330).

5. The packaging box film sealing machine according to claim 4, wherein a guide rail (340) is arranged at the top of the supporting plate (320), the connecting block (330) is slidably connected with the guide rail (340), and the guide rail (340) and the baffle (290) are parallel to each other.

6. A packaging box film sealing machine according to claim 1, wherein two first air cylinders (180) are arranged, and the two first air cylinders (180) respectively drive the two first ironing plates (170) to move.

7. A packaging film sealing machine according to claim 1, characterized in that the work bench (230) is provided with a mounting plate (350), the mounting plate (350) being used for mounting the third cylinder (280).

8. A packaging box film sealing machine according to claim 7, wherein the fourth ironing plate (270) is provided with a first guide rod (360), and the mounting plate (350) is provided with a first guide hole for accommodating the first guide rod (360) to pass through.

9. A packaging box film sealing machine according to claim 8, wherein two first guide rods (360) are arranged, and the two first guide rods (360) are respectively arranged at two sides of the third air cylinder (280).

10. A packaging box film sealing machine according to claim 1, wherein the second ironing plate (200) is provided with two second guide rods (370), the bracket (190) is provided with two second guide holes, the two second guide rods (370) respectively penetrate through the two second guide holes, and the two second guide rods (370) are respectively positioned at two sides of the second air cylinder (210).