CN214163092U

CN214163092U - Plastic bag cutting device

Info

Publication number: CN214163092U
Application number: CN202023258818.3U
Authority: CN
Inventors: 王存波
Original assignee: Qingdao Guangxinyuan Packaging Material Co ltd
Current assignee: Qingdao Guangxinyuan Packaging Material Co ltd
Priority date: 2020-12-29
Filing date: 2020-12-29
Publication date: 2021-09-10
Anticipated expiration: 2030-12-29

Abstract

The utility model discloses a plastic bag cutting device, which relates to the technical field of plastic bag production equipment and comprises a base, wherein support frames are fixedly arranged on both sides of the upper surface of the base, a wind-up roll is rotatably arranged between the two support frames, a servo motor is fixedly arranged on one side of any one support frame, and a driving end of the servo motor is in transmission connection with the wind-up roll; a plurality of support rods are integrally and fixedly arranged at the two ends of the winding roller, the support rods are in one-to-one correspondence, and connecting rods are arranged between the support rods in a sliding manner; mounting rods are fixedly arranged at two ends of the wind-up roll, limiting plates are arranged on one sides of the two mounting rods, which are far away from the wind-up roll, in parallel, mounting boxes are arranged on the limiting plates, which are arranged on the wind-up roll in a sliding manner along the length direction of the wind-up roll, and cutting knives are arranged in the mounting boxes in a sliding manner; two flattening blocks are arranged on two adjacent connecting rods of the limiting plate in a lifting mode. The screw rod rotates to drive the mounting box to slide on the limiting plate, and the mounting box drives the cutting knife to cut the plastic bag, so that the function of automatically cutting the plastic bag is realized.

Description

Plastic bag cutting device

Technical Field

The utility model relates to a plastic bag production facility technical field especially relates to a plastic bag cutting device.

Background

The plastic bag is a bag made of plastic serving as a main raw material and is an essential article in daily life of people, a double-layer plastic film needs to be made of plastic in the production process of the plastic bag, then the plastic film is thermally sealed to be made into a long plastic bag, the long plastic bag is cut into small plastic bags in a point-breaking and cutting mode, and a winding device needs to be used for winding the long plastic bag before the cutting process.

Aiming at the problem of winding of plastic bags, a Chinese patent with a patent publication number of CN203922179U provides a plastic bag winding device, which comprises a base, wherein a main bracket and an auxiliary bracket are respectively arranged at two ends of the base, and a limiting groove for placing a winding drum is fixed at the top end of the auxiliary bracket; both sides of the top end of the main support are provided with shaft sleeves, a winding roller is arranged between the two shaft sleeves, a plurality of groups of adjustable winding mechanisms which are crossed and arranged in a radial shape are installed on the winding roller, and one end of the winding roller is fixedly connected with a handle.

According to the technical scheme, workers cut the plastic bags into equal sections, the manual cutting efficiency is low, the plastic bags are easily damaged in the cutting process, and the quality of a single plastic bag finished product is influenced.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a plastic bag cutting device has the automatic cutout plastic bag, keeps the neat and quick braking wind-up roll's of plastic bag incision department function.

The utility model discloses a can realize through following technical scheme:

a plastic bag cutting device comprises a base, wherein support frames are fixedly arranged on two sides of the upper surface of the base, a discharging roller and a winding roller are rotatably arranged between the two support frames, a servo motor is fixedly arranged on one side of any one support frame, and a driving end of the servo motor is in transmission connection with the winding roller; a plurality of support rods are fixedly arranged at both ends of the winding roller integrally, correspond to each other one by one and are provided with connecting rods in a sliding manner; mounting rods are fixedly arranged at two ends of the winding roller, a limiting plate is arranged on one side, away from the winding roller, of each mounting rod in parallel, a mounting box is arranged on each limiting plate in a sliding mode along the length direction of the winding roller, and a cutting knife is arranged in each mounting box in a sliding mode; two flattening blocks are arranged on the two adjacent connecting rods of the limiting plate in a lifting mode; a movable plate is arranged between the two support frames in a lifting mode, a cutting groove is formed in one side, facing the mounting box, of the movable plate, and the cutting groove is located right above the cutting knife.

By adopting the technical scheme, before the plastic bag is rolled, a worker rotates the material receiving roller to enable the mounting box to be positioned right above the material rolling roller, and then the material discharging end of the plastic bag is adhered to the connecting rod which is at the same side as the mounting box and close to the material discharging roller; when the plastic bag is wound, the winding roller rotates, the plastic bag is gradually wound and wound around the connecting rod, when the plastic bag is wound to a specified number of turns and the mounting box is positioned right above the winding roller, the piston block moves towards the air inlet groove, the piston block pushes air into the air inlet groove, and the gradually compressed air pushes the clamping block to prop against the inner wall of the support frame, so that the winding roller stops rotating, and the rapid braking is realized when the winding roller rotates to a required position; then the flattening blocks at the two ends of the connecting rod move oppositely and then uniformly move towards the winding roller until the flattening blocks and the connecting rod are attached to the plastic bag in a staggered mode, so that the plastic bag is tensioned, and the plastic bag is prevented from falling off after being cut off; when the piston blocks move in opposite directions, the movable plate descends until the movable plate is tightly attached to the roller and tightly clamps the plastic bag together with the roller, the cutting knife in the mounting box rises at the moment, the mounting box slides in the groove, the cutting knife cuts the plastic bag along the cutting groove, quick cutting of the plastic bag is realized, and the cutting opening of the plastic bag is neat, so that the cutting quality is improved.

Further setting the following steps: the mounting box is internally provided with a limiting groove, a movable block is arranged in the limiting groove in a sliding manner and fixedly connected with the cutting knife, one side of the mounting box is fixedly provided with a propulsion cylinder, the end part of a piston rod of the propulsion cylinder is fixedly provided with a sliding block, one side of the sliding block is provided with an inclined plane, and one side of the movable block is matched with the inclined plane.

Through adopting the above technical scheme, when cutting the plastic bag, it starts and promotes the slider and removes to impel the cylinder, slider jack-up movable block, the movable block drives the cutting knife and rises, later the mounting box drives the cutting knife and slides, cut the plastic bag, the plastic bag is cut off the back, impel the cylinder to reset and drive the slider and roll back, make the cutting knife retrieve to spacing inslot, the stretching out and the recovery function of cutting knife have been realized, the cutting knife only just can rise when the cutting, prevent that the staff from by the cutting knife fish tail, and the protection cutting knife has prolonged the life of cutting knife.

Further setting the following steps: one side of the movable block, which is far away from the winding roller, is fixedly provided with a limiting spring, and the limiting spring is fixedly connected with the inner wall of the limiting groove.

Through adopting above-mentioned technical scheme, the cutting knife compresses spacing spring when rising, and when the cutting finishes, the cutting knife can be withdrawed fast to spacing spring's elastic force effect, protection staff's safety.

Further setting the following steps: one side of the limiting plate, which is far away from the wind-up roll, is provided with a groove, and a convex block is fixedly arranged on the mounting box and is matched with the groove in a sliding manner.

Through adopting above-mentioned technical scheme, realized that the mounting box slides on the limiting plate.

Further setting the following steps: two it is provided with the screw rod to rotate between the installation pole, the screw rod screw thread is worn to locate the mounting box, arbitrary set firmly step motor on the installation pole, step motor with the screw rod transmission is connected.

Through adopting above-mentioned technical scheme, the cutting knife rises the back, and step motor starts and drives the screw rod and rotates, and the screw rod drives the mounting box and slides on the limiting plate, realizes the cutting to the plastic bag.

Further setting the following steps: the mounting box is provided with a plurality of running rollers towards one side rotation of limiting plate.

Through adopting above-mentioned technical scheme, the fly leaf descends, pastes tight running roller and tightly presss from both sides the plastic bag with running roller resultant force until it, and the running roller rotates when the mounting box slides, can avoid the mounting box to rub the plastic bag at the in-process that slides, causes the damage to the plastic bag.

Further setting the following steps: a plurality of clamping grooves are formed in one end of the winding roller, clamping blocks are arranged in the clamping grooves in a sliding mode, and clamping springs are fixedly arranged in the clamping grooves and are fixedly connected with the clamping blocks.

Through adopting above-mentioned technical scheme, can withstand the support frame inner wall when the fixture block protrusion wind-up roll's outer wall, the reverse effort of support frame inner wall makes the wind-up roll unable rotation.

Further setting the following steps: an air inlet groove is formed in the center of one end of the winding roller and communicated with the clamping grooves, and a piston block is arranged in the air inlet groove in a sliding mode.

Through adopting above-mentioned technical scheme, in pushing into the air inlet duct with the air, the air that compresses gradually promotes the fixture block and withstands support frame inner wall, and support frame inner wall's reaction force makes wind-up roll stall, has realized braking fast when the wind-up roll rotates to required position.

Further setting the following steps: the movable plate is provided with a guide groove which is funnel-shaped, and one side of the guide groove with a small opening is connected with the cutting groove.

Through adopting above-mentioned technical scheme, the guiding groove can play the effect that the guide cutting knife got into the cutting groove, takes place to hit the sword when preventing that the cutting knife from getting into the cutting groove, causes the cutter body to damage.

Further setting the following steps: the connecting rod both ends all set firmly the lantern ring, the bracing piece penetrates in the lantern ring, adjusting bolt is worn to be equipped with by one side screw thread of lantern ring.

Through adopting above-mentioned technical scheme, the staff loosens adjusting bolt and can adjust the connecting rod, and every winding round is the length that needs cut off promptly after the adjustment, and keeps the heat-seal line all the time directly over the wind-up roll to the cutting knife is to its cutting.

To sum up, the utility model discloses a beneficial technological effect does:

(1) the screw rod rotates to drive the mounting box to slide on the limiting plate, and the mounting box drives the cutting knife to cut the plastic bag, so that the function of automatically cutting the plastic bag is realized.

(2) By arranging the movable plate and the cutting groove, when the plastic bag is cut, the movable plate descends and abuts against the roller, so that the function of stabilizing the plastic bag before the plastic bag is cut by the cutting knife is realized; the cutting knife cuts the plastic bag along the cutting groove, so that the cut of the plastic bag is neat, and the cutting quality is improved.

(3) In pushing into the air inlet duct through the piston piece, the air that compresses gradually promotes the fixture block and withstands the support frame inner wall, and the reaction force of support frame inner wall makes wind-up roll stall, has realized quick braking when the wind-up roll rotates to required position.

Drawings

Fig. 1 is a schematic view of the overall structure of the present invention;

FIG. 2 is an enlarged view of a portion A of FIG. 1;

fig. 3 is a top view of the present invention;

FIG. 4 is a cross-sectional view taken along line B-B of FIG. 3;

FIG. 5 is an enlarged view of a portion C of FIG. 4;

FIG. 6 is a cross-sectional view taken along line D-D of FIG. 3;

fig. 7 is an enlarged view of a portion E of fig. 6.

FIG. 8 is an enlarged view of a portion F of FIG. 6

Reference numerals: 1. a base; 2. a support frame; 3. a wind-up roll; 4. a servo motor; 5. a support bar; 6. a connecting rod; 7. mounting a rod; 8. a limiting plate; 9. mounting a box; 10. a cutting knife; 11. flattening the block; 12. a movable plate; 13. cutting the groove; 14. a limiting groove; 15. a movable block; 16. propelling the cylinder; 17. a slider; 18. a bevel; 19. a limiting spring; 20. a groove; 21. a bump; 22. a screw; 23. a stepping motor; 24. a roller; 25. a guide groove; 26. an adjusting cylinder; 27. a lifting cylinder; 28. a piston block; 29. a telescopic cylinder; 30. a discharge roller; 31. metal wrapping; 32. an air inlet groove; 33. a chucking spring; 34. a clamping block; 35. a card slot; 36. clamping the air cylinder; 37. a collar; 38. adjusting the bolt; 39. and (5) fixing blocks.

Detailed Description

The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

Referring to fig. 1, for the utility model discloses a plastic bag cutting device, including base 1, base 1 upper surface both sides have all set firmly support frame 2, rotate between two support frames 2 and are provided with wind-up roll 3 and blowing roller 30, and one side of arbitrary support frame 2 has set firmly servo motor 4, and servo motor 4's drive end passes through the shaft coupling and is connected with 3 transmissions of wind-up roll. The servo motor 4 is started and drives the winding roller 3 to rotate, and the function of winding the plastic bag is achieved.

Referring to fig. 2 and 4, 3 both ends of wind-up roll all set firmly two spinal branch vaulting poles 5, and wind-up roll 3 is the cross structure with two spinal branch vaulting poles 5 of one side, and the one-to-one just slides between the two between the bracing piece 5 at 3 both ends of wind-up roll is provided with connecting rod 6, and connecting rod 6 is total four and all with wind-up roll 3 parallel arrangement, and 6 both ends of connecting rod have all set firmly the lantern ring 37, and in bracing piece 5 penetrated the lantern ring 37, adjusting bolt 38 was worn to be equipped with by one side screw thread of lantern ring 37. Before the plastic bag rolling, the staff rotates wind-up roll 3, the mounting box 9 mentioned below is rotated to the wind-up roll 3 directly over, later the staff loosens adjusting bolt 38 and can adjust connecting rod 6, every wind the length that the round is required to cut off around connecting rod 6 after the adjustment, and keep the heat seal line all the time to remain directly over wind-up roll 3, so that the cutting knife 10 mentioned below cuts it, locking adjusting bolt 38 after the position is confirmed, glue the plastic bag of the discharge end of blowing roller 30 on the connecting rod 6 with mounting box 9 homonymy and be close to blowing roller 30.

Referring to fig. 6 and 8, a plurality of clamping grooves 35 are formed in one end of the wind-up roll 3, clamping blocks 34 are arranged in the clamping grooves 35 in a sliding mode, clamping springs 33 are fixedly arranged in the clamping grooves 35, and the clamping springs 33 are fixedly connected with the clamping blocks 34. An air inlet groove 32 is formed in the center of one end of the winding roller 3, the air inlet groove 32 is communicated with a plurality of clamping grooves 35, a piston block 28 is arranged in the air inlet groove 32 in a sliding mode, a clamping cylinder 36 is fixedly arranged at one end of the winding roller 3, the piston block 28 is fixedly arranged at the end portion of a piston rod of the clamping cylinder 36, and the piston block 28 extends into the air inlet groove 32. Referring to fig. 2, the servo motor 4 starts and drives the wind-up roll 3 to rotate, the plastic bag is wound and wound around four connecting rods 6 gradually, when the plastic bag is wound to a specified number of turns and the mounting box 9 mentioned below rotates right above the wind-up roll 3, the chucking cylinder 36 starts and drives the piston block 28 to move, the piston block 28 pushes air into the air inlet groove 32, the air is compressed gradually and pushes the fixture block 34 after entering the clamping groove 35, the fixture block 34 protrudes out of the surface of the wind-up roll 3 and abuts against the inner wall of the support frame 2, the reverse acting force of the inner wall of the support frame 2 on the fixture block 34 makes the wind-up roll 3 unable to rotate, thereby achieving the purpose that the plastic bag is wound around the wind-up roll 3 for a certain number of turns and locks the wind-up roll 3 when the mounting box 9 rotates to be located right above the wind-up roll 3. After the wind-up roll 3 stops rotating, the clamping cylinder 36 drives the piston block 28 to reset, and the clamping block 34 retracts into the clamping groove 35 under the elastic force of the clamping spring 33.

Referring to fig. 2 and 5, the both ends of wind-up roll 3 all set firmly installation pole 7, and one side that wind-up roll 3 was kept away from to two installation poles 7 sets firmly limiting plate 8 with wind-up roll 3 parallel arrangement, slides along its length direction on the limiting plate 8 and is provided with mounting box 9, and recess 20 has been seted up to one side that wind-up roll 3 was kept away from to limiting plate 8, has set firmly lug 21 on mounting box 9, and lug 21 and recess 20 cooperation of sliding. A screw 22 is rotatably arranged in the groove 20, the screw 22 penetrates through the mounting box 9 in a threaded manner, a stepping motor 23 is fixedly arranged at one end of the limiting plate 8, and the stepping motor 23 is in transmission connection with the screw 22. After the cutting knife 10 mentioned below rises, the stepping motor 23 starts and drives the screw rod 22 to rotate, the screw rod 22 drives the mounting box 9 to slide on the limiting plate 8, the mounting box 9 slides on the limiting plate 8 through the convex block 21 and the groove 20, and the plastic bag is cut. The mounting box 9 rotates towards one side of limiting plate 8 and is provided with four running rollers 24, and four running rollers 24 evenly distributed in the both sides of cutting knife 10. The movable plate 12 mentioned below descends until the movable plate 12 clings to the roller 24 and cooperates with the roller 24 to clamp the plastic bag, and the roller 24 rotates when the mounting box 9 slides, so that the plastic bag can be prevented from being damaged by the plastic bag rubbed by the mounting box 9 in the moving process.

Referring to fig. 6 and 7, a cutting knife 10 is slidably arranged in the mounting box 9, a limiting groove 14 is formed in the mounting box 9, a movable block 15 is slidably arranged in the limiting groove 14, the movable block 15 is fixedly connected with the cutting knife 10, a propulsion cylinder 16 is fixedly arranged on one side of the mounting box 9, a sliding block 17 is fixedly arranged at the end of a piston rod of the propulsion cylinder 16, an inclined surface 18 is arranged on one side of the sliding block 17, and one side of the movable block 15 is matched with the inclined surface 18. When cutting the plastic bag, the propulsion cylinder 16 starts and promotes the slider 17 and remove, and slider 17 jack-up movable block 15, movable block 15 drive cutting knife 10 and rise, and later mounting box 9 drives cutting knife 10 and slides, cuts the plastic bag. After the plastic bag is cut off, it resets and drives slider 17 and rolls back to impel cylinder 16 for cutting knife 10 is withdrawed to spacing groove 14 in, realizes stretching out and withdrawing of cutting knife 10, and cutting knife 10 only just can rise when the cutting, can prevent that the staff from being by cutting knife 10 fish tail, and the life of protection cutting knife 10 extension cutting knife 10. And a limiting spring 19 is fixedly arranged on one side of the movable block 15, which is far away from the winding roller 3, and the limiting spring 19 is fixedly connected with the inner wall of the limiting groove 14. When the cutting knife 10 rises, the limiting spring 19 is compressed, and when cutting is finished, the cutting knife 10 can be quickly retracted into the mounting box 9 under the elastic force action of the limiting spring 19.

Referring to fig. 2 and 3, two flattening blocks 11 are arranged on two adjacent connecting rods 6 of the limiting plate 8 in a lifting mode, an adjusting cylinder 26 is fixedly arranged on four adjacent supporting frames 2 of the limiting plate 8, a fixing block 39 is fixedly arranged at the end part of a piston rod of the adjusting cylinder 26, a telescopic cylinder 29 is fixedly arranged on one side, far away from the material receiving roller, of the fixing block 39, and the end part of the piston rod of the telescopic cylinder 29 is fixedly connected with the flattening blocks 11. When the plastic bag is completely wound, the telescopic cylinder 29 is started and drives the flattening blocks 11 to move in opposite directions, and when the piston rod of the telescopic cylinder 29 extends to the maximum length, the adjusting cylinder 26 is started and drives the telescopic cylinder 29 to move towards the winding roller 3 until the flattening blocks 11 are abutted against the connecting rods 6 and are attached to the connecting rods 6 in a staggered mode, so that the plastic bag is tensioned.

Referring to fig. 2 and 7, a movable plate 12 is disposed between the two support frames 2 in a lifting manner, a cutting groove 13 is formed in one side of the movable plate 12 facing the mounting box 9, and the cutting groove 13 is located right above the cutting knife 10. The lift cylinder 27 starts and drives the fly leaf 12 and descends, closes tightly the plastic bag until it pastes tight running roller 24 and with running roller 24 closes with the power of force, and the cutting knife 10 in the mounting box 9 rises afterwards, slides along the mounting box 9, and cutting knife 10 cuts the plastic bag along cutting groove 13, and this kind of cutting mode can make the incision department of plastic bag neat, improves the plastic bag cutting quality. The movable plate 12 is provided with a guide groove 25, the guide groove 25 is funnel-shaped, and the side of the guide groove 25 with a small opening is connected with the cutting groove 13. The guiding groove 25 can guide the cutting knife 10 to enter the cutting groove 13, and prevent the cutting knife 10 from colliding with the cutting groove 13 to damage the knife body. And metal covering edges 31 are fixedly arranged on two sides of the opening of the cutting groove 13. The cutting knife 10 and the cutting groove 13 are matched with each other to form a two-edge staggered structure, so that paper is cut, and the paper cutting effect is good.

The utility model discloses a theory of operation does:

before the plastic bag is wound, a worker rotates the winding roller 3 to enable the mounting box 9 to be located right above the winding roller 3, and then the discharge end of the plastic bag is adhered to the connecting rod 6 which is on the same side as the mounting box 9 and close to the discharging roller 30; when plastic bags are wound, the winding roller 3 rotates, the plastic bags are wound and wound around the connecting rod 6 gradually, when the plastic bags are wound to a specified number of turns and the mounting box 9 is positioned right above the winding roller 3, the piston blocks 28 move towards the air inlet groove 32, the piston blocks 28 push air into the air inlet groove 32, and the gradually compressed air pushes the clamping blocks 34 to prop against the inner wall of the support frame 2, so that the winding roller 3 stops rotating; then, the flattening blocks 11 at the two ends of the connecting rod 6 move in opposite directions and then move towards the wind-up roll 3 uniformly until the flattening blocks 11 are attached to the connecting rod 6 in a staggered mode to tension the plastic bag; when the piston blocks 28 move in opposite directions, the movable plate 12 descends until the movable plate clings to the roller 24 and tightly clamps the plastic bag together with the roller 24, at the moment, the cutting knife 10 in the mounting box 9 rises, the mounting box 9 slides in the groove 20, the cutting knife 10 cuts the plastic bag along the cutting groove 13, the movable plate 12, the piston blocks 28, the flattening blocks 11 and the cutting knife 10 reset in advance after the plastic bag is cut off, then the mounting box 9 resets, and a worker takes away the plastic bag and sticks the plastic bag on the connecting rod 6 which is at the same side as the mounting box 9 and is close to the discharging roller 30.

The utility model has the advantages that:

the screw 22 rotates to drive the mounting box 9 to slide on the limiting plate 8, and the mounting box 9 drives the cutting knife 10 to cut the plastic bag, so that the function of automatically cutting the plastic bag is realized. By arranging the movable plate 12 and the cutting groove 13, when the plastic bag is cut, the movable plate 12 descends and abuts against the roller 24, so that the function of stabilizing the plastic bag before the cutting knife 10 cuts the plastic bag is realized; the cutting knife 10 cuts the plastic bag along the cutting groove 13, so that the cut of the plastic bag is neat, and the cutting quality is improved. Air is pushed into the air inlet groove 32 through the piston block 28, the gradually compressed air pushes the clamping block 34 to abut against the inner wall of the support frame 2, the reaction force of the inner wall of the support frame 2 enables the wind-up roll 3 to stop rotating, and the fast braking when the wind-up roll 3 rotates to a required position is realized.

The above, only do the preferred embodiment of the present invention, not limit the protection scope of the present invention according to this, so: all equivalent changes made according to the structure, shape and principle of the utility model are covered within the protection scope of the utility model.

Claims

1. A plastic bag cutting device is characterized in that: the winding machine comprises a base (1), wherein support frames (2) are fixedly arranged on two sides of the upper surface of the base (1), a discharging roller (30) and a winding roller (3) are rotatably arranged between the two support frames (2), a servo motor (4) is fixedly arranged on one side of any one support frame (2), and a driving end of the servo motor (4) is in transmission connection with the winding roller (3); a plurality of support rods (5) are integrally and fixedly arranged at two ends of the winding roller (3), the support rods (5) are in one-to-one correspondence, and connecting rods (6) are arranged between the support rods and the support rods in a sliding manner; mounting rods (7) are fixedly arranged at two ends of the winding roller (3), a limiting plate (8) is arranged on one side, far away from the winding roller (3), of the two mounting rods (7) in parallel, a mounting box (9) is arranged on the limiting plate (8) in a sliding mode along the length direction of the winding roller (3), and a cutting knife (10) is arranged in the mounting box (9) in a sliding mode; two flattening blocks (11) are arranged on the two adjacent connecting rods (6) of the limiting plate (8) in a lifting manner; a movable plate (12) is arranged between the two support frames (2) in a lifting mode, a cutting groove (13) is formed in one side, facing the mounting box (9), of the movable plate (12), and the cutting groove (13) is located right above the cutting knife (10).

2. The plastic bag cutting apparatus according to claim 1, wherein: a limiting groove (14) is formed in the mounting box (9), a movable block (15) is arranged in the limiting groove (14) in a sliding mode, the movable block (15) is fixedly connected with the cutting knife (10), a propulsion cylinder (16) is fixedly arranged on one side of the mounting box (9), a sliding block (17) is fixedly arranged at the end portion of a piston rod of the propulsion cylinder (16), an inclined plane (18) is arranged on one side of the sliding block (17), and one side of the movable block (15) is matched with the inclined plane (18).

3. The plastic bag cutting apparatus according to claim 2, wherein: one side of the movable block (15) far away from the winding roller (3) is fixedly provided with a limiting spring (19), and the limiting spring (19) is fixedly connected with the inner wall of the limiting groove (14).

4. The plastic bag cutting apparatus according to claim 3, wherein: one side, far away from wind-up roll (3), of limiting plate (8) is provided with a groove (20), a convex block (21) is fixedly arranged on mounting box (9), and convex block (21) is matched with groove (20) in a sliding manner.

5. The plastic bag cutting apparatus according to claim 4, wherein: two it is provided with screw rod (22) to rotate between installation pole (7), screw rod (22) screw thread is worn to locate mounting box (9), arbitrary set firmly step motor (23) on installation pole (7), step motor (23) with screw rod (22) transmission is connected.

6. The plastic bag cutting apparatus according to claim 5, wherein: the mounting box (9) is provided with a plurality of rollers (24) towards one side of the limiting plate (8) in a rotating mode.

7. The plastic bag cutting apparatus according to claim 1, wherein: a plurality of clamping grooves (35) are seted up to wind-up roll (3) one end, the inside sliding of clamping groove (35) is provided with fixture block (34), clamping spring (33) just have set firmly in clamping groove (35) clamping spring (33) with fixture block (34) link firmly.

8. The plastic bag cutting apparatus according to claim 7, wherein: an air inlet groove (32) is formed in the center of one end of the winding roller (3), the air inlet groove (32) is communicated with the clamping grooves (35), and a piston block (28) is arranged in the air inlet groove (32) in a sliding mode.

9. The plastic bag cutting apparatus according to claim 1, wherein: the movable plate (12) is provided with a guide groove (25), the guide groove (25) is funnel-shaped, and one side of the guide groove (25) with a small opening is connected with the cutting groove (13).

10. The plastic bag cutting apparatus according to claim 1, wherein: the utility model discloses a support rod, including connecting rod (6), bracing piece (5), connecting rod, bracing piece, connecting rod and connecting rod, the lantern ring (37) both ends all set firmly, bracing piece (5) penetrate in the lantern ring (37), adjusting bolt (38) are worn to be equipped with by one side screw thread of lantern ring (37).