阅读说明：本技术 一种根据薄膜厚度自调节高度的绿色包装膜用覆膜装置 (According to film thickness self-interacting high green packaging film with tectorial membrane device ) 是由 张振旭 于 2021-07-09 设计创作，主要内容包括：本发明涉及绿色包装膜技术领域,且公开了一种根据薄膜厚度自调节高度的绿色包装膜用覆膜装置,包括牵引轮,所述牵引轮的内部开设有环形排列的液压腔,所述液压腔相背的一侧均开设有回油孔和进油孔,所述回油孔的内部均转动连接有球塞,所述牵引轮的前后内壁之间焊接有弹性气囊,所述牵引轮的外部插接有环形排列的牵引机构,所述牵引轮的内侧壁插接有环形排列的调节机构。通过位于下方的控制板受到包装膜向上的挤压力,进而带动下方的控制板收缩,控制板收缩时会通过支撑弹簧带动挤压板挤压弹性油囊,弹性油囊内的液压油在压力的作用下从进油孔进入液压腔内,直到不会继续收缩,从而达到了根据薄膜厚度自动调节牵引机构高度的效果。(The invention relates to the technical field of green packaging films, and discloses a film laminating device for a green packaging film, wherein the height of the green packaging film is self-adjusted according to the thickness of a film, the film laminating device comprises a traction wheel, a hydraulic cavity which is annularly arranged is formed in the traction wheel, an oil return hole and an oil inlet hole are formed in the opposite side of the hydraulic cavity, a ball plug is rotatably connected in the oil return hole, an elastic air bag is welded between the front inner wall and the rear inner wall of the traction wheel, an annularly arranged traction mechanism is inserted in the outer part of the traction wheel, and an annularly arranged adjusting mechanism is inserted in the inner side wall of the traction wheel. Receive the ascending extrusion force of packaging film through the control panel that is located the below, and then drive the control panel shrink of below, can drive stripper plate extrusion elasticity oil pocket through supporting spring during the control panel shrink, hydraulic oil in the elasticity oil pocket gets into the hydraulic pressure intracavity from the inlet port under the effect of pressure until can not continue the shrink to reached according to the effect of film thickness automatically regulated drive mechanism height.)

1. The utility model provides a height is from adjusting tectorial membrane device for green packaging film according to film thickness, includes traction wheel (1), its characterized in that: the utility model discloses a traction wheel, including traction wheel (1), hydraulic pressure chamber (11) that the annular was arranged are seted up to the inside of traction wheel (1), oil gallery (12) and inlet port (13) have all been seted up to one side that hydraulic pressure chamber (11) carried on the back mutually, the inside of oil gallery (12) all rotates and is connected with ball stopper (6), the welding has elastic air bag (2) around traction wheel (1) between the inner wall, the outside grafting of traction wheel (1) has drive mechanism (3) that the annular was arranged, the inside wall grafting of traction wheel (1) has adjustment mechanism (4) that the annular was arranged, the both sides of drive mechanism (3) all rotate and are connected with stop gear (5).

2. The film covering device for green packaging film of claim 1, wherein the height is self-adjusted according to the film thickness, and the device comprises: traction mechanism (3) include movable rod (31), control panel (32) have all been welded to one side that movable rod (31) carried on the back mutually, two supporting spring (33) have all been welded to one side that control panel (32) is in opposite directions, supporting spring (33) one side in opposite directions all has welded stripper plate (34), stripper plate (34) one side in opposite directions all sliding connection have elasticity oil pocket (35).

3. The film covering device for green packaging film of claim 2, wherein the height is self-adjusted according to the film thickness, and the device comprises: one side that oil gallery (12) and inlet port (13) carried on the back mutually all communicates with elasticity oil pocket (35), the inside of elasticity oil pocket (35) and hydraulic pressure chamber (11) all is equipped with hydraulic oil, the inside of inlet port (13) all is provided with the check valve, the through-hole has been seted up in the left side of ball stopper (6), the bottom of ball stopper (6) is provided with the balancing weight.

4. The film covering device for green packaging film of claim 1, wherein the height is self-adjusted according to the film thickness, and the device comprises: adjustment mechanism (4) are including extrusion stem (41), extrusion piston (42) have all been welded to one side that extrusion stem (41) carried on the back mutually, arc push pedal (43) have all been welded to one side in opposite directions of extrusion stem (41).

5. The film covering device for green packaging film of claim 4, wherein the height is self-adjusted according to the film thickness, and the device comprises: the extrusion pistons (42) are located inside the hydraulic cavity (11), and the extrusion rods (41) are sleeved with adjusting springs.

6. The film covering device for green packaging film of claim 2, wherein the height is self-adjusted according to the film thickness, and the device comprises: the limiting mechanism (5) comprises a limiting clamping wheel (51), a rotating wheel (52) is inserted into the limiting clamping wheel (51), and an arc-shaped clamping block (53) is rotatably connected to the inner rear wall of the rotating wheel (52).

7. The film covering device for green packaging film, which adjusts height automatically according to film thickness, as claimed in claim 6, wherein: the draw-in groove that the annular was arranged is seted up to the inside wall of spacing calorie of wheel (51), arc fixture block (53) are located the draw-in groove, the bottom of arc fixture block (53) all is provided with the balancing weight, movable rod (31) both sides all are provided with the shrink tooth that the equidistance was arranged, movable rod (31) are through shrink tooth and spacing calorie of wheel (51) meshing.

Technical Field

The invention relates to the technical field of green packaging films, in particular to a film laminating device for a green packaging film, wherein the height of the film laminating device is self-adjusted according to the thickness of the film.

Background

The green packaging material is a material or material product which can save resources and energy sources, can be rapidly and naturally degraded or recycled after being discarded, cannot damage ecological balance, has wide sources and low energy consumption, is easy to recycle and has high recycling rate, and common green packaging materials of people mainly comprise degradable plastics, natural biomolecular materials and the like.

Along with the improvement of people's environmental protection consciousness, the use amount of green packaging film is also higher and higher, the tectorial membrane is essential step when the packing, the drive mechanism of current laminating machine can not be according to the thickness self-regulation height of packaging film when using, lead to changing behind the packaging film of different thickness, the phenomenon that many films were pulled out simultaneously appears easily, reduce the quality of packing, cause the waste of film simultaneously, we have proposed a tectorial membrane device for green packaging film according to film thickness self-interacting height from this.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention aims to provide a film covering device for green packaging films, the height of which is self-adjusted according to the thickness of the film, and the film covering device has the advantage of automatically adjusting the height of a traction mechanism according to the thickness of the film.

The invention adopts the following technical scheme for realizing the technical purpose: the utility model provides a green tectorial membrane device for packaging film according to film thickness self-interacting height, includes the traction wheel, the hydraulic pressure chamber that the annular was arranged is seted up to the inside of traction wheel, oil gallery and inlet port have all been seted up to one side that the hydraulic pressure chamber was carried on the back mutually, the inside of oil gallery all rotates and is connected with the ball stopper, the welding has elastic airbag between the inner wall around the traction wheel, peg graft in the outside of traction wheel has the drive mechanism that the annular was arranged, peg graft in the inside wall of traction wheel and have the adjustment mechanism that the annular was arranged, drive mechanism's both sides all rotate and are connected with stop gear.

As optimization, drive mechanism includes the movable rod, the control panel has all been welded to one side that the movable rod carried on the back mutually, two supporting spring have all been welded to one side that the control panel is in the same direction, supporting spring in the same direction all has been welded the stripper plate, the equal sliding connection in one side in the same direction of stripper plate has the elasticity oil pocket, and supporting spring plays the effect of extrusion control panel and stripper plate.

As optimization, one side that oil gallery and inlet port carried on the back mutually all communicates with the elastic oil bag, the inside in elastic oil bag and hydraulic pressure chamber all is equipped with hydraulic oil, the inside of inlet port all is provided with the check valve, and the check valve can restrict the hydraulic oil in the hydraulic pressure chamber and get into the elastic oil bag from the inlet port, the through-hole has been seted up in the left side of ball stopper, the bottom of ball stopper is provided with the balancing weight, and the balancing weight can make the through-hole on the ball stopper be in the horizontality all the time.

As optimization, the adjusting mechanism comprises an extrusion rod, extrusion pistons are welded on one sides of the extrusion rod, which are opposite to each other, and arc-shaped push plates are welded on one sides of the extrusion rod, which are opposite to each other.

Preferably, the extrusion pistons are located inside the hydraulic cavity, and the extrusion rods are sleeved with the adjusting springs to achieve the effect of extruding the extrusion pistons.

Preferably, the limiting mechanism comprises a limiting clamping wheel, a rotating wheel is inserted into the limiting clamping wheel, and an arc-shaped clamping block is rotatably connected to the inner rear wall of the rotating wheel.

As optimization, the draw-in groove that the annular was arranged is seted up to the inside wall of spacing calorie of wheel, the arc fixture block is located the draw-in groove, plays the spacing calorie of wheel pivoted effect of restriction, the bottom of arc fixture block all is provided with the balancing weight, and the balancing weight can make the arc fixture block can not rotate along with stop gear's rotation, the movable rod both sides all are provided with the shrink tooth that the equidistance was arranged, the movable rod passes through shrink tooth and spacing calorie of wheel meshing, and when the movable rod was retracted in the traction wheel, the shrink tooth can not drive spacing calorie of wheel rotation, and when the movable rod stretched out the traction wheel, the shrink tooth can stretch out and mesh with spacing calorie of wheel.

Compared with the prior art, the invention provides the film laminating device for the green packaging film, the height of which is self-adjusted according to the thickness of the film, and the film laminating device has the following beneficial effects:

1. the film covering device for the green packaging film with the height self-adjusted according to the thickness of the film drives the traction mechanism to rotate through the traction wheel, the control plate positioned below is firstly contacted with the packaging film, and is pressed upwards by the packaging film, the thickness of the packaging film is different, the pressing force is also different, and then the control panel below is driven to contract, the extrusion plate is driven to extrude the elastic oil bag through the supporting spring when the control panel contracts, hydraulic oil in the elastic oil bag pushes open the one-way valve in the oil inlet hole under the action of pressure and enters the hydraulic cavity from the oil inlet hole, until the extrusion force applied to the control panel is transmitted to the elastic oil bag through the supporting spring and the extrusion plate, the one-way valve in the oil inlet hole is not enough to be opened, and the control panel can not continuously contract at the moment, thereby reached according to the effect of film thickness automatically regulated drive mechanism height, do not need staff's manual regulation.

2. This according to film thickness self-interacting laminating device for green packaging film of height, can drive the movable rod and remove to the traction wheel when contracting through the control panel, when the movable rod removes to the traction wheel, can automatic shrink when the shrink tooth of its both sides and spacing calorie of wheel contact, can not drive spacing calorie of wheel rotation, when the movable rod wants to stretch out, can stretch out when shrink tooth and spacing calorie of wheel contact, and then mesh with spacing calorie of wheel, rotate the arc fixture block in the wheel this moment and block in the draw-in groove under the effect of balancing weight, can restrict spacing calorie of wheel rotation, and then restrict the movable rod and drive the control panel and stretch out, the removal of control panel has been restricted with the extrusion force cooperation of film to the control panel, thereby reached the effect of avoiding the excessive extrusion film of control panel, make the control panel be in appropriate scope all the time to the traction force of film.

3. This according to film thickness self-height-adjusting's tectorial membrane device for green packaging film, increase the back through the oil mass in the hydraulic pressure intracavity in below, can drive extrusion piston to the direction that is close to elastic air bag and remove, and then drive arc push pedal extrusion elastic air bag through the stripper bar, elastic air bag receives the extrusion back, its inside pressure can grow, and then the reaction force grow for all the other arc push pedals, this moment is in the horizontality with the oil gallery of left side drive mechanism intercommunication, the through-hole on the ball stopper also is in the horizontality under the effect of balancing weight, oil gallery and through-hole intercommunication, and then make elastic oil bag and hydraulic pressure chamber intercommunication, the arc fixture block on the left side stop gear breaks away from in the draw-in groove under the effect of balancing weight simultaneously, no longer restrict spacing card wheel and rotate, elastic air bag receives left arc push pedal of extrusion back extrusion left side behind the arc push pedal, and then drive the hydraulic oil in the left side hydraulic pressure intracavity through extrusion piston and get back to elastic oil through oil gallery and through the through-hole on oil gallery and the ball stopper In the bag, the elastic oil bag drives the extrusion plate and the control plate to reset, so that the height of the control plate can be readjusted when the film is pulled by the traction mechanism every time, and the effect of avoiding overlarge or undersize traction force of the control plate on the film due to uneven thickness of the film is achieved.

Drawings

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

FIG. 2 is an enlarged view of the portion A of FIG. 1 according to the present invention;

FIG. 3 is an enlarged view of the portion B of FIG. 2 according to the present invention;

FIG. 4 is an enlarged schematic view of the limiting mechanism of FIG. 3 according to the present invention;

FIG. 5 is an enlarged view of the structure of the portion C in FIG. 2 according to the present invention.

In the figure: 1. a traction wheel; 11. a hydraulic chamber; 12. an oil return hole; 13. an oil inlet hole; 2. an elastic air bag; 3. a traction mechanism; 31. a movable rod; 32. a control panel; 33. a support spring; 34. a pressing plate; 35. an elastic oil pocket; 4. an adjustment mechanism; 41. an extrusion stem; 42. a squeeze piston; 43. an arc-shaped push plate; 5. a limiting mechanism; 51. a limiting clamping wheel; 52. a rotating wheel; 53. an arc-shaped fixture block; 6. and (4) a ball plug.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The first embodiment is as follows:

please refer to fig. 1-2, a film covering device for green packaging film according to film thickness self-adjusting height, including traction wheel 1, hydraulic pressure chamber 11 that the annular was arranged is seted up to traction wheel 1's inside, return oil hole 12 and inlet port 13 have all been seted up to one side that hydraulic pressure chamber 11 was carried on the back mutually, the inside of return oil hole 12 all rotates and is connected with ball stopper 6, welding elasticity gasbag 2 between the inner wall around traction wheel 1, the outside of traction wheel 1 is pegged graft and is had the drive mechanism 3 that the annular was arranged, the inside wall of traction wheel 1 is pegged graft and is had the adjustment mechanism 4 that the annular was arranged, the both sides of drive mechanism 3 all rotate and are connected with stop gear 5.

Traction mechanism 3 includes movable rod 31, control panel 32 has all been welded to one side that movable rod 31 carried on the back mutually, two supporting spring 33 have all been welded to one side that control panel 32 is in opposite directions, stripper plate 34 has all been welded to one side that supporting spring 33 is in opposite directions, the equal sliding connection of one side in opposite directions of stripper plate 34 has elastic oil bag 35, supporting spring 33 plays the effect of extrusion control panel 32 and stripper plate 34, one side that oil gallery 12 and inlet port 13 carried on the back mutually all communicates with elastic oil bag 35, hydraulic oil is all equipped with to elastic oil bag 35 and hydraulic pressure chamber 11's inside, the inside of inlet port 13 all is provided with the check valve, the check valve can restrict hydraulic pressure intracavity 11 in hydraulic oil gets into elastic oil bag 35 from inlet port 13, the through-hole has been seted up in the left side of ball stopper 6, the bottom of ball stopper 6 is provided with the balancing weight, the balancing weight can make the through-hole on the ball stopper 6 be in the horizontality all the time.

Drive mechanism 3 through traction wheel 1 and rotate, the control panel 32 that is located the below at first contacts with the packaging film, and receive the ascending extrusion force of packaging film, the thickness of packaging film is different, the extrusion force that receives is also different, and then drive the shrink of the control panel 32 of below, can drive stripper plate 34 extrusion elasticity oil pocket 35 through supporting spring 33 during the control panel 32 shrink, hydraulic oil in the elasticity oil pocket 35 is under the effect of pressure with the single-way valve in the inlet port 13 to be washed away, get into hydraulic chamber 11 from the inlet port 13, when the extrusion force that until control panel 32 received transmits for elasticity oil pocket 35 through supporting spring 33 and stripper plate 34, be not enough to open the check valve in the inlet port 13, control panel 32 can not continue the shrink this moment, thereby reached according to the effect of film thickness automatically regulated drive mechanism 3 height, staff's manual regulation does not need.

Example two:

please refer to fig. 1-4, a film covering device for green packaging film according to film thickness self-adjusting height, comprising a traction wheel 1, a hydraulic chamber 11 arranged in an annular shape is provided inside the traction wheel 1, an oil return hole 12 and an oil inlet hole 13 are provided on one side of the hydraulic chamber 11 opposite to each other, the inside of the oil return hole 12 is connected with a ball plug 6 in a rotating manner, an elastic air bag 2 is welded between the front and rear inner walls of the traction wheel 1, a traction mechanism 3 arranged in an annular shape is inserted outside the traction wheel 1, an adjusting mechanism 4 arranged in an annular shape is inserted in the inner side wall of the traction wheel 1, and a limiting mechanism 5 is connected to both sides of the traction mechanism 3 in a rotating manner.

The traction mechanism 3 comprises a movable rod 31, a control plate 32 is welded on one side of the movable rod 31 opposite to each other, two support springs 33 are welded on one side of the control plate 32 opposite to each other, extrusion plates 34 are welded on one sides of the support springs 33 opposite to each other, elastic oil bags 35 are connected on one sides of the extrusion plates 34 opposite to each other in a sliding mode, the support springs 33 play a role in extruding the control plate 32 and the extrusion plates 34, a limiting mechanism 5 comprises a limiting clamp wheel 51, a rotating wheel 52 is inserted into the limiting clamp wheel 51, an arc-shaped clamping block 53 is rotatably connected to the inner rear wall of the rotating wheel 52, clamping grooves which are annularly arranged are formed in the inner side wall of the limiting clamp wheel 51, the arc-shaped clamping block 53 is positioned in the clamping grooves and plays a role in limiting the rotation of the limiting clamp wheel 51, balancing weights are arranged at the bottoms of the arc-shaped clamping blocks 53 and can enable the arc-shaped clamping block 53 not to rotate along with the rotation of the limiting mechanism 5, shrinkage teeth which are arranged at equal intervals are arranged on two sides of the movable rod 31, the movable rod 31 is meshed with the limiting clamping wheel 51 through the contraction teeth, when the movable rod 31 retracts into the traction wheel 1, the contraction teeth cannot drive the limiting clamping wheel 51 to rotate, and when the movable rod 31 extends out of the traction wheel 1, the contraction teeth can extend out of the limiting clamping wheel 51 to be meshed.

Can drive movable rod 31 when contracting through control panel 32 and remove to traction wheel 1, when movable rod 31 removed in to traction wheel 1, can automatic shrink when the shrink tooth of its both sides and spacing calorie of wheel 51 contact, can not drive spacing calorie of wheel 51 and rotate, when movable rod 31 wants to stretch out, can stretch out when shrink tooth and spacing calorie of wheel 51 contact, and then mesh with spacing calorie of wheel 51, rotate arc fixture block 53 in the wheel 52 this moment and block in the draw-in groove under the effect of balancing weight, can restrict spacing calorie of wheel 51 and rotate, and then restriction movable rod 31 drives control panel 32 and stretches out, the removal of control panel 32 has been restricted to the extrusion force cooperation of control panel 32 with the film, thereby reached the effect of avoiding control panel 32 excessively to extrude the film, make control panel 32 be in appropriate scope to the traction force of film all the time.

Example three:

please refer to fig. 1-5, a film covering device for green packaging film according to film thickness self-adjusting height, comprising a traction wheel 1, a hydraulic chamber 11 arranged in an annular shape is provided inside the traction wheel 1, an oil return hole 12 and an oil inlet hole 13 are provided on one side of the hydraulic chamber 11 opposite to each other, the inside of the oil return hole 12 is connected with a ball plug 6 in a rotating manner, an elastic air bag 2 is welded between the front and rear inner walls of the traction wheel 1, a traction mechanism 3 arranged in an annular shape is inserted outside the traction wheel 1, an adjusting mechanism 4 arranged in an annular shape is inserted in the inner side wall of the traction wheel 1, and a limiting mechanism 5 is connected to both sides of the traction mechanism 3 in a rotating manner.

The traction mechanism 3 comprises a movable rod 31, a control plate 32 is welded on one side of the movable rod 31 opposite to each other, two supporting springs 33 are welded on one side of the control plate 32 opposite to each other, extrusion plates 34 are welded on one sides of the supporting springs 33 opposite to each other, elastic oil bags 35 are slidably connected on one sides of the extrusion plates 34 opposite to each other, the supporting springs 33 play a role of extruding the control plate 32 and the extrusion plates 34, one sides of the oil return holes 12 opposite to the oil inlet holes 13 are communicated with the elastic oil bags 35, hydraulic oil is filled in the elastic oil bags 35 and the hydraulic cavity 11, check valves are arranged in the oil inlet holes 13 and can limit the hydraulic oil in the hydraulic cavity 11 to enter the elastic oil bags 35 from the oil inlet holes 13, a through hole is formed in the left side of the ball plug 6, a balancing weight is arranged at the bottom of the ball plug 6 and can enable the through hole in the ball plug 6 to be always in a horizontal state, the adjusting mechanism 4 comprises an extrusion rod 41, extrusion pistons 42 are welded on one opposite sides of the extrusion rods 41, arc push plates 43 are welded on one opposite sides of the extrusion rods 41, the extrusion pistons 42 are located inside the hydraulic cavities 11, adjusting springs are sleeved outside the extrusion rods 41 to play a role in extruding the extrusion pistons 42, the limiting mechanism 5 comprises limiting clamp wheels 51, rotating wheels 52 are inserted inside the limiting clamp wheels 51, arc-shaped clamping blocks 53 are rotatably connected to the inner rear walls of the rotating wheels 52, clamping grooves which are annularly arranged are formed in the inner side walls of the limiting clamp wheels 51, the arc-shaped clamping blocks 53 are located in the clamping grooves to play a role in limiting rotation of the limiting clamp wheels 51, balancing weights are arranged at the bottoms of the arc-shaped clamping blocks 53, the balancing weights can enable the arc-shaped clamping blocks 53 not to rotate along with rotation of the limiting mechanism 5, shrinkage teeth which are equidistantly arranged on two sides of the movable rod 31, the movable rod 31 is meshed with the limiting clamp wheels 51 through the shrinkage teeth, when the movable rod 31 retracts into the traction wheel 1, the contraction teeth cannot drive the limiting clamping wheel 51 to rotate, and when the movable rod 31 extends out of the traction wheel 1, the contraction teeth can extend out to be meshed with the limiting clamping wheel 51.

Increase the back through the oil mass in the below hydraulic pressure chamber 11, can drive extrusion piston 42 to the direction removal that is close to elastic airbag 2, and then drive arc push pedal 43 extrusion elastic airbag 2 through extrusion stem 41, elastic airbag 2 receives the extrusion back, its inside pressure can grow, and then the reaction force grow for all the other arc push pedal 43, this moment is in the horizontality with the oil gallery 12 of left side drive mechanism 3 intercommunication, the through-hole on ball stopper 6 also is in the horizontality under the effect of balancing weight, oil gallery 12 and through-hole intercommunication, and then make elastic oil bag 35 and hydraulic pressure chamber 11 intercommunication, arc fixture block 53 on the left side stop gear 5 breaks away from in the draw-in groove under the effect of balancing weight simultaneously, no longer restrict spacing card wheel 51 and rotate, elastic airbag 2 receives left side extrusion arc push pedal 43 behind the extrusion of below arc push pedal 43, and then drive the hydraulic oil in the left side hydraulic pressure chamber 11 through extrusion piston 42 and get back to elastic oil bag 35 through oil gallery 12 and the through-hole on ball stopper 6 In the film drawing device, the elastic oil bag 35 drives the extrusion plate 34 and the control plate 32 to reset, so that the height of the control plate 32 can be adjusted again when the film is drawn by the drawing mechanism 3 every time, and the effect of avoiding overlarge or undersize drawing force of the control plate 32 on the film due to uneven thickness of the film is achieved.

Example four:

please refer to fig. 1-5, a film covering device for green packaging film according to film thickness self-adjusting height, comprising a traction wheel 1, a hydraulic chamber 11 arranged in an annular shape is provided inside the traction wheel 1, an oil return hole 12 and an oil inlet hole 13 are provided on one side of the hydraulic chamber 11 opposite to each other, the inside of the oil return hole 12 is connected with a ball plug 6 in a rotating manner, an elastic air bag 2 is welded between the front and rear inner walls of the traction wheel 1, a traction mechanism 3 arranged in an annular shape is inserted outside the traction wheel 1, an adjusting mechanism 4 arranged in an annular shape is inserted in the inner side wall of the traction wheel 1, and a limiting mechanism 5 is connected to both sides of the traction mechanism 3 in a rotating manner.

The traction mechanism 3 comprises a movable rod 31, a control plate 32 is welded on one side of the movable rod 31 opposite to each other, two supporting springs 33 are welded on one side of the control plate 32 opposite to each other, extrusion plates 34 are welded on one sides of the supporting springs 33 opposite to each other, elastic oil bags 35 are slidably connected on one sides of the extrusion plates 34 opposite to each other, the supporting springs 33 play a role of extruding the control plate 32 and the extrusion plates 34, one sides of the oil return holes 12 opposite to the oil inlet holes 13 are communicated with the elastic oil bags 35, hydraulic oil is filled in the elastic oil bags 35 and the hydraulic cavity 11, check valves are arranged in the oil inlet holes 13 and can limit the hydraulic oil in the hydraulic cavity 11 to enter the elastic oil bags 35 from the oil inlet holes 13, a through hole is formed in the left side of the ball plug 6, a balancing weight is arranged at the bottom of the ball plug 6 and can enable the through hole in the ball plug 6 to be always in a horizontal state, the adjusting mechanism 4 comprises an extrusion rod 41, extrusion pistons 42 are welded on one opposite sides of the extrusion rods 41, arc push plates 43 are welded on one opposite sides of the extrusion rods 41, the extrusion pistons 42 are located inside the hydraulic cavities 11, adjusting springs are sleeved outside the extrusion rods 41 to play a role in extruding the extrusion pistons 42, the limiting mechanism 5 comprises limiting clamp wheels 51, rotating wheels 52 are inserted inside the limiting clamp wheels 51, arc-shaped clamping blocks 53 are rotatably connected to the inner rear walls of the rotating wheels 52, clamping grooves which are annularly arranged are formed in the inner side walls of the limiting clamp wheels 51, the arc-shaped clamping blocks 53 are located in the clamping grooves to play a role in limiting rotation of the limiting clamp wheels 51, balancing weights are arranged at the bottoms of the arc-shaped clamping blocks 53, the balancing weights can enable the arc-shaped clamping blocks 53 not to rotate along with rotation of the limiting mechanism 5, shrinkage teeth which are equidistantly arranged on two sides of the movable rod 31, the movable rod 31 is meshed with the limiting clamp wheels 51 through the shrinkage teeth, when the movable rod 31 retracts into the traction wheel 1, the contraction teeth cannot drive the limiting clamping wheel 51 to rotate, and when the movable rod 31 extends out of the traction wheel 1, the contraction teeth can extend out to be meshed with the limiting clamping wheel 51.

The working principle is as follows: when in use, the traction mechanism 3 is driven to rotate by the traction wheel 1, the control plate 32 positioned at the lower part is firstly contacted with the packaging film, and is pressed upwards by the packaging film, the thickness of the packaging film is different, the pressing force is also different, and then the control board 32 below is driven to contract, when the control board 32 contracts, the extrusion board 34 is driven by the supporting spring 33 to extrude the elastic oil bag 35, the hydraulic oil in the elastic oil bag 35 pushes open the one-way valve in the oil inlet 13 under the action of pressure, and enters the hydraulic cavity 11 from the oil inlet 13 until the extrusion force applied to the control board 32 is transmitted to the elastic oil bag 35 through the supporting spring 33 and the extrusion board 34, it is not enough to open the check valve in the oil inlet hole 13, at which time the control plate 32 does not continue to contract, therefore, the effect of automatically adjusting the height of the traction mechanism 3 according to the thickness of the film is achieved, and manual adjustment by workers is not needed; can drive movable rod 31 when contracting through control panel 32 and remove to traction wheel 1, when movable rod 31 removed in to traction wheel 1, can automatic shrink when the shrink tooth of its both sides and spacing calorie of wheel 51 contact, can not drive spacing calorie of wheel 51 and rotate, when movable rod 31 wants to stretch out, can stretch out when shrink tooth and spacing calorie of wheel 51 contact, and then mesh with spacing calorie of wheel 51, rotate arc fixture block 53 in the wheel 52 this moment and block in the draw-in groove under the effect of balancing weight, can restrict spacing calorie of wheel 51 and rotate, and then restriction movable rod 31 drives control panel 32 and stretches out, the removal of control panel 32 has been restricted to the extrusion force cooperation of control panel 32 with the film, thereby reached the effect of avoiding control panel 32 excessively to extrude the film, make control panel 32 be in appropriate scope to the traction force of film all the time.

Increase the back through the oil mass in the below hydraulic pressure chamber 11, can drive extrusion piston 42 to the direction removal that is close to elastic airbag 2, and then drive arc push pedal 43 extrusion elastic airbag 2 through extrusion stem 41, elastic airbag 2 receives the extrusion back, its inside pressure can grow, and then the reaction force grow for all the other arc push pedal 43, this moment is in the horizontality with the oil gallery 12 of left side drive mechanism 3 intercommunication, the through-hole on ball stopper 6 also is in the horizontality under the effect of balancing weight, oil gallery 12 and through-hole intercommunication, and then make elastic oil bag 35 and hydraulic pressure chamber 11 intercommunication, arc fixture block 53 on the left side stop gear 5 breaks away from in the draw-in groove under the effect of balancing weight simultaneously, no longer restrict spacing card wheel 51 and rotate, elastic airbag 2 receives left side extrusion arc push pedal 43 behind the extrusion of below arc push pedal 43, and then drive the hydraulic oil in the left side hydraulic pressure chamber 11 through extrusion piston 42 and get back to elastic oil bag 35 through oil gallery 12 and the through-hole on ball stopper 6 In the film drawing device, the elastic oil bag 35 drives the extrusion plate 34 and the control plate 32 to reset, so that the height of the control plate 32 can be adjusted again when the film is drawn by the drawing mechanism 3 every time, and the effect of avoiding overlarge or undersize drawing force of the control plate 32 on the film due to uneven thickness of the film is achieved.

Having shown and described embodiments of the present invention, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and alterations can be made in the embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.