CN113777041A

CN113777041A - Film flaw detection device and detection method

Info

Publication number: CN113777041A
Application number: CN202111075429.3A
Authority: CN
Inventors: 刘勤学; 王郑聊; 周旭; 李林
Original assignee: Ningbo Qinbang New Material Technology Co ltd
Current assignee: Ningbo Qinbang New Material Technology Co ltd
Priority date: 2021-09-14
Filing date: 2021-09-14
Publication date: 2021-12-10

Abstract

The application discloses a film flaw detection device and a detection method, which comprises a rack, a conveying mechanism and a detection mechanism; the rack is used for supporting and fixing the conveying mechanism and the detection mechanism; the conveying mechanism is used for conveying the film to pass through the detection mechanism; the detection mechanism comprises an airflow seat and a sensing table, the airflow seat and the sensing table are respectively arranged on two sides of the film, the airflow seat is suitable for ejecting airflow to the film, the airflow is suitable for penetrating through the defect part of the film, a plurality of sensing blocks are distributed on the sensing table and are suitable for sensing the airflow penetrating through the film and acquiring the position information of the airflow occurrence part, and the detection device can rapidly detect, record and mark the defect part of the solar backboard film in the production process, so that subsequent analysis is facilitated, and the process is improved.

Description

Film flaw detection device and detection method

Technical Field

The application relates to the technical field of solar cells, in particular to a film defect detection device and a detection method.

Background

The main production process methods of the solar cell back plate include three types: the solar back plate is a three-layer composite process of a fluorine-containing film such as PVF/PVDF and the like, a BOPET film, a PVF/PVDF and the like, which is widely accepted by manufacturers of photovoltaic module brands, namely the solar back plate is composed of a three-layer structure, wherein the outer layer is a T film, the middle layer is a P film, and the T film and the P film are bonded by glue. Wherein T represents a fluorine-containing film such as polyvinyl fluoride (PVF)/polyvinylidene fluoride (PVDF), and the layer is used as a main layer of a solar cell packaging material and has the functions of weather resistance, UV resistance, aging resistance and the like; p represents a polyester film (BOPET) and has the main functions and functions of electrical insulation, water vapor barrier property, resistance to wet heat aging, dimensional stability, tear resistance, easy processability and the like; one kind is to take a common polyester film (BOPET) as a middle layer substrate, compound modified polyester films on two sides, namely a three-layer compound process of modified polyester film, common polyester film and modified polyester film, wherein the modified polyester film material is equivalent to the function and function of a fluorine-containing film; the third type is that polyester film (BOPET) is used as a substrate, and fluorine-containing resin is coated and cured on the surface of the polyester film by a surface coating process.

With the further improvement of the requirements of photovoltaic cell assembly manufacturers on prolonging the service life of the cell and the photoelectric conversion efficiency, the requirements on the polyester film which is a matching material of the photovoltaic cell are more and more strict, the produced film has the requirements on soft, flat and smooth surface, and has no defects of wrinkles, tearing, particles, bubbles, pinholes, external impurities and the like, and the edge of the film is neat and has no damage.

However, the existing production process of the solar back sheet film has the following defects: because the film is transparent material, and is comparatively frivolous, be difficult to comparatively comprehensive discovery flaw and the defect on the film in process of production, it is not ideal to use optical principle to carry out analysis recognition effect.

Disclosure of Invention

An object of the present application is to provide a film defect detecting apparatus and a detecting method capable of rapidly detecting, recording and marking a defect portion of a solar back sheet film in a production process.

In order to achieve the above purposes, the technical scheme adopted by the application is as follows: a film flaw detection device and a detection method comprise a frame, a conveying mechanism and a detection mechanism;

the rack is used for supporting and fixing the conveying mechanism and the detection mechanism;

the conveying mechanism is used for conveying the film to pass through the detection mechanism;

the detection mechanism comprises an airflow seat and a sensing table, the airflow seat and the sensing table are respectively arranged on two sides of the film, the airflow seat is suitable for ejecting airflow to the film, the airflow is suitable for penetrating through the flaw part of the film, a plurality of sensing blocks are distributed on the sensing table, and the sensing blocks are suitable for sensing the airflow penetrating through the film and acquiring the position information of the airflow occurrence part.

The induction table comprises an induction top plate and an induction screen plate, the induction top plate, the induction screen plate, a film and an airflow seat are sequentially arranged in the detection mechanism from top to bottom, a plurality of induction columns are arranged at equal intervals below the induction top plate, the induction columns are provided with a current-conducting plate in an up-and-down sliding mode, a plurality of fixed meshes are uniformly formed in the induction screen plate, conducting plates are distributed around the fixed meshes, the induction screen plate is provided with conducting heads connected with the conducting plates, the induction columns are installed in a matched mode in the fixed meshes, the conducting plates are conducted with the conducting plates when static, and the conducting plates are suitable for being blown by airflow generated at the defect of the film and are disconnected with the conducting plates.

As an improvement, the main body shape of the conductive plate is cross-shaped, independent conductive circuits are arranged on the conductive plate in the longitudinal direction and the transverse direction, and the conductive circuits are suitable for respectively connecting the conductive plates in the longitudinal direction and the conductive plates in the transverse direction.

As an improvement, a plurality of air inlets are uniformly arranged around the air flow seat, a plurality of air outlets communicated with the air inlets are arranged above the air flow seat at equal intervals, a constant pressure cavity is arranged in the air flow seat and is respectively communicated with the air inlets and the air inlets, the ratio of the total area of the air inlets to the total area of the air outlets is alpha, and alpha is more than or equal to 1.4 and less than or equal to 1.6.

As an improvement, the end part of the induction column is conical, the gas outlet is provided with injection pipes, and the injection pipes are matched with the induction column one by one.

As an improvement, still include marking mechanism, marking mechanism includes guide rail, motor, slip subassembly and mark head, the guide rail transversely set up in the film top of detection mechanism's ejection of compact side, slip subassembly slidable set up in on the guide rail, mark head detachable set up in on the slip subassembly, the motor is used for control slip subassembly's slip, slip subassembly includes transmission wheelset and pulley, one side of guide rail is provided with connects the tooth, transmission wheelset with guide rail rack and pinion connects, the opposite side of guide rail is provided with the sliding tray, the pulley sets up in the sliding tray to the cooperation transmission wheelset centre gripping the guide rail.

As an improvement, the marking mechanism further comprises an imaging device, the imaging device is arranged in the detection mechanism, and the imaging device is used for shooting a film picture at the position where the airflow appears.

Specifically, the conveying mechanism comprises a feeding roller, a coiling roller and a conveying wheel set, the feeding roller and the coiling roller are arranged at two ends of the rack, the conveying wheel set is arranged at two sides of the rack, the conveying wheel set comprises a first conveying wheel and a second conveying wheel, the first conveying wheel and the second conveying wheel are matched with each other to clamp the film, and the first conveying wheel and the second conveying wheel are suitable for enabling the film to move towards the coiling roller.

As an improvement, the conveying wheel set is arranged around the detection mechanism, the conveying wheel set is matched with and tensions the film in the detection mechanism, force measuring modules are arranged at two ends of the winding roller, and the force measuring modules are suitable for detecting pulling force at two ends of the winding roller so as to control the rotating speed of the conveying wheel set at two sides of the rack.

A method for detecting defects of a thin film comprises the following steps:

a film to be detected is wound on the feeding roller, a guide film is arranged at the front end of the film and connected with the winding roller, and the conveying wheel set tensions the film in the detection mechanism;

the air flow seat is used for inflating the constant-pressure cavity through the air inlet and then injecting air to the film from the air outlet through the injection pipe, and the air flow is suitable for being injected to the induction column through the flaw part of the film so as to disconnect the circuit of the conductive plate and the conductive plate;

the induction table acquires position information of a circuit disconnection position, and the image device shoots and archives a damaged position of the film;

the material rolling roller and the conveying wheel set synchronously rotate to enable the next part to be detected of the film to enter the detection mechanism, the material rolling roller receives the detected film, the force measuring module detects the pulling force at two ends of the material rolling roller when the material rolling roller is received, and adjusts the rotating speed of the conveying wheel set at two sides of the film in real time to enable the film not to transversely shift when moving;

the background system calculates a marking position and marking time through position information at a circuit breaking position and the rotating speed of the conveying wheel set, the sliding assembly enables the marking head to move to the position above the marking position in advance according to data calculated by the background system, and after the marking time, the marking head sprays color paint to mark the damaged position of the film.

Compared with the prior art, the beneficial effect of this application lies in: utilize gas to detect the physical properties and the flaw defect of the film of production, its tensile strength and surface tension of gaseous oppression film detectable, if there is slight damaged flaw or the weak position that the performance is not enough on the film, can be fast with its identification record, and use image device to shoot and stay the shelves, rethread marking mechanism sprays the damaged position of coating mark, thereby be convenient for follow-up carry out the improvement that the production technology was realized to the problem analysis, this check out test set structure is comparatively simple, the manufacturing difficulty is low, the not fragile film that does not have the flaw position in the testing process, can carry out regional detection to the film, detection efficiency is high.

Drawings

FIG. 1 is a perspective view of a preferred embodiment according to the present application;

FIG. 2 is an exploded view of a preferred embodiment according to the present application;

FIG. 3 is a front view of a preferred embodiment according to the present application;

FIG. 4 is an enlarged structural view of an inductive column according to a preferred embodiment of the present application;

FIG. 5 is an enlarged view at a in FIG. 2 according to a preferred embodiment of the present application;

FIG. 6 is an enlarged view at b of FIG. 2 in accordance with a preferred embodiment of the present application;

FIG. 7 is an overall structural view of a conveying wheel set according to a preferred embodiment of the present application;

fig. 8 is an overall structural view of a marking mechanism according to a preferred embodiment of the present application.

In the figure: 1. a frame; 2. a conveying mechanism; 21. a feed roller; 22. a material rolling roller; 221. a force measuring module; 23. a conveying wheel set; 231. a first delivery wheel; 232. a second delivery wheel; 3. a detection mechanism; 31. an induction table; 311. an induction top plate; 3111. an induction column; 3112. a conductive plate; 312. sensing the screen plate; 3121. fixing meshes; 3122. a conductive sheet; 3123. a conductive head; 32. an airflow seat; 321. an air inlet; 322. an air outlet; 3221. an injection pipe; 323. a constant pressure chamber; 4. a marking mechanism; 41. a guide rail; 411. a sliding groove; 42. a motor; 43. a sliding assembly; 431. a transmission wheel set; 432. a pulley; 44. a marking head; 45. an imaging device.

Detailed Description

The present application is further described below with reference to specific embodiments, and it should be noted that, without conflict, any combination between the embodiments or technical features described below may form a new embodiment.

In the description of the present application, it should be noted that, for the terms of orientation, such as "central", "lateral", "longitudinal", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., it indicates that the orientation and positional relationship shown in the drawings are based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, but does not indicate or imply that the device or element referred to must have a specific orientation, be constructed in a specific orientation, and be construed as limiting the specific scope of protection of the present application.

It is noted that the terms first, second and the like in the description and in the claims of the present application are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order.

The terms "comprises," "comprising," and "having," and any variations thereof, in the description and claims of this application, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

The present application is further described with reference to the accompanying drawings:

as shown in fig. 1 to 3, a preferred embodiment of the present application includes a frame 1, a conveying mechanism 2, a detecting mechanism 3, and a marking mechanism 4.

The frame 1 is used for supporting and fixing the conveying mechanism 2, the detection mechanism 3 and the marking mechanism 4.

Conveying mechanism 2 includes feed roll 21 and winding up roller 22, and feed roll 21 and winding up roller 22 set up in the both ends of frame 1, and feed roll 21 is suitable for placing the film that waits to detect, and winding up roller 22 is suitable for accomodating the film after detecting, can in time accomodate the film, reduces the probability that the film damaged in detecting the flow.

The marking mechanism 4 is disposed between the detection mechanism 3 and the winding roller 22, and the marking mechanism 4 is used for marking the defect position of the detected film.

The detection mechanism 3 comprises an airflow seat 32 and a sensing table 31, the airflow seat 32 and the sensing table 31 are respectively arranged on two sides of the film, the airflow seat 32 is suitable for spraying airflow to the film, the airflow is suitable for penetrating through the flaw part of the film, a plurality of sensing blocks are distributed on the sensing table 31, and the sensing blocks are suitable for sensing the airflow penetrating through the film and acquiring the position information of the airflow occurrence part.

As shown in fig. 2 to 6, the sensing platform 31 includes a sensing top plate 311 and a sensing screen plate 312, the sensing top plate 311 is sequentially disposed from top to bottom in the detection mechanism 3, the sensing screen plate 312, a film and an airflow seat 32, a plurality of sensing posts 3111 are disposed below the sensing top plate 311 at equal intervals, a conductive plate 3112 is disposed at the sensing posts 3111 in an up-and-down sliding manner, a plurality of fixed meshes 3121 are uniformly disposed on the sensing screen plate 312, conductive plates 3122 are distributed around the fixed meshes 3121, the fixed meshes 3121 and the conductive plates 3122 form a sensing block, conductive heads 3123 connected to the conductive plates 3122 are disposed around the sensing screen plate 312, the sensing posts 3111 are installed in the fixed meshes 3121 in a matching manner, the conductive plates 3112 are conducted with the conductive plates 3122 when in a static state, the conductive plates 3112 are suitable for being blown by the airflow occurring at the film defect and disconnected from the conductive plates 3122.

The shape of conducting plate 3112 is the cross, conducting plate 3112 is provided with independent conducting wire longitudinally and transversely, be convenient for when setting up conducting plate 3112, align conducting wire and conducting plate 3122, avoid the conducting wire skew and do not switch on conducting plate 3122, the conducting wire is suitable for switching on vertically conducting plate 3122 and transversely upward conducting plate 3122 respectively, because fixed mesh 3121 can't the undersize, can only carry out the affirmation of scope nature when conducting plate 3112 breaks off, separate setting horizontal circuit and vertical circuit, the break-make that breaks away from only can trigger a circuit takes place for the one end of conducting plate 3112, break-make through two circuits can increase the detection precision, can roughly fix a position which side of defect position in mesh, thereby the small defect of easier location.

A plurality of air inlets 321 are uniformly arranged around the air flow seat 32, a plurality of air outlets 322 communicated with the air inlets 321 are arranged above the air flow seat 32 at equal intervals, a constant pressure cavity 323 is arranged in the air flow seat 32, the constant pressure cavity 323 is respectively communicated with the air inlets 321 and the air inlets 321, the ratio of the total area of the air inlets 321 to the total area of the air outlets 322 is alpha, alpha is more than or equal to 1.4 and less than or equal to 1.6, the constant pressure cavity 323 can balance the air pressure of each air outlet 322, so that the air pressure is the same, uniform air flow impacts the thin film to be subjected to the same compression force during detection, the detection precision is increased, the total area of the air inlets 321 and the total area of the air outlets 322 need to be in the proportion range of 1.4 to 1.6, thereby ensuring that the air flow intensity at the air outlets 322 meets the detection requirements (meets the critical value of the thin film intensity), the flawless thin film is damaged when the air flow intensity is too high, and the detection requirement cannot be met when the air flow intensity is too low, defective portions cannot be detected effectively.

The bottom of response post 3111 is the toper, be provided with injection pipe 3221 on the gas outlet 322, injection pipe 3221 aligns the setting with response post 3111 cooperation one by one, injection pipe 3221 can provide comparatively concentrated air current, the damaged back of film, if damaged department undersize, can be probably because of the not enough current intensity can't blow the current conducting plate 3112, injection pipe 3221 can promote air current intensity, but response post 3111's toper design effective dispersion air current, guide air current strikes current conducting plate 3112, promote the response precision.

The sensing net plate 312 is utilized to subdivide the detection area into a plurality of small areas, each small area is a small grid, and if the film at the position is damaged or the strength of the film at the position is not enough to be blown by wind flowing out of the air outlet, the conductive plate 3112 can be separated from the conductive sheet 3122 around the area, so that the damaged position of the corresponding film can be quickly and accurately positioned.

As shown in fig. 7, the conveying mechanism 2 further includes a conveying wheel set 23, the conveying wheel set 23 is disposed on two sides of the frame 1, the conveying wheel set 23 includes a first conveying wheel 231 and a second conveying wheel 232, the first conveying wheel 231 and the second conveying wheel 232 are respectively disposed on the upper side and the lower side of the film, the first conveying wheel 231 and the second conveying wheel 232 are suitable for conveying the film to move toward the material winding roller 22, and through the cooperation of the first conveying wheel 231 and the second conveying wheel 232, the stress of the film in the conveying process can be balanced, and the pulling force during the movement can be reduced.

The feed roller 21 has no rotation capability, but can be provided with rotation damping, when the roll-up roller 22 and the conveying wheel set 23 convey films, the feed roller 21 can be driven to rotate for feeding, the rotation damping can avoid the feed roller 21 from spreading excessive films, the two ends of the roll-up roller 22 are provided with the force measuring modules 221, the force measuring modules 221 preferably use pressure sensors, the force measuring modules 221 are suitable for detecting the pulling force at the two ends of the roll-up roller 22, so as to control the rotating speed of the conveying wheel sets 23 at the two sides of the frame 1, the feeding speed of the conveying wheel sets 23 at the two sides is adjusted according to the detected pulling force, if the pulling force at the right end of the roll-up roller 22 is greater than that at the left end, the conveying wheel set 23 at the right side slows down the rotating speed to reduce the pulling force of the film at the right side, and vice versa, the pulling force at the two sides of the film is balanced by the force measuring modules 221, so as to improve the flatness of the film wound into the roll-up roller 22, and the pulling caused by different conveying speeds of the two sides of the film which is not coiled into the coiling roller 22 can be avoided, and the probability of the film damage in the conveying process can be reduced.

Conveying wheelset 23 sets up around detection mechanism 3, and conveying wheelset 23 cooperates the film in the tensioning detection mechanism 3, and conveying wheelset 23 sets up and plays location and supporting role in detecting the structure four corners to the film, and dynamics when making the film receive the air current oppression is more balanced, avoids the film to lead to taking place to damage in the non-defective department because of the atress is uneven.

As shown in fig. 8, the marking mechanism 4 includes a guide rail 41, a motor 42, a sliding assembly 43 and a marking head 44, the guide rail 41 is transversely disposed above the film, the sliding assembly 43 is slidably disposed on the guide rail 41, the marking head 44 is detachably disposed on the sliding assembly 43, the marking head 44 is fixed on the sliding assembly 43 by a snap, a paint connecting pipe is connectable to an upper portion of the marking head 44, the marking head is externally connected to a paint spraying device, and the motor 42 is used for controlling the sliding of the sliding assembly 43.

The sliding assembly 43 comprises a transmission wheel set 431 and a pulley 432, one side of the guide rail 41 is provided with a connecting tooth, the transmission wheel set 431 is in gear-rack connection with the guide rail 41, the motor 42 rotates through controlling the transmission wheel set 431 to transversely move on the guide rail 41, the other side of the guide rail 41 is provided with a sliding groove 411, the pulley 432 is arranged in the sliding groove 411 in a matched mode, the stability of the marking head 44 can be enhanced through the combination of the transmission wheel set 431 and the pulley 432, and the color paint is not prone to shaking when being sprayed.

The marking mechanism 4 can position the detection result, and when the background system gave the mark signal through calculating, a certain amount of colour coating can be spouted to the mark head 44, makes things convenient for follow-up direct damaged position to the film to observe the analysis, and the photo when the detection that cooperates the image device 45 to shoot can obtain more comprehensive data, reduces the optimization degree of difficulty of production technology and equipment.

As shown in fig. 3, the marking mechanism 4 includes a marking mechanism 4, the marking mechanism 45 includes an imaging device 45, the imaging device 45 is used for taking a film photo of the place where the airflow appears, and then uploading the photo to a background system for retaining, when optimizing the process and the equipment, the photo can be used for analysis and comparison, targeted optimization is performed, and optimization efficiency is improved.

The detection device can detect and screen the defective film, can also optimize the production process and production equipment by recording and marking the defect position of the film, and reduces the defect number of the subsequently produced film.

The application also provides a film defect detection method, which comprises the following steps:

a film to be detected is wound on the feeding roller 21, a guide film is arranged at the front end of the film and connected with the winding roller 22, and the conveying wheel set 23 tensions the film in the detection mechanism 3;

the air flow seat 32 inflates air into the constant pressure cavity 323 through the air inlet 321, and then sprays air to the film from the air outlet 322 through the spraying pipe 3221, and the air flow is suitable for penetrating through the flaw part of the film to be sprayed to the position of the induction column 3111, so that the electric circuit between the conductive plate 3112 and the conductive plate 3122 is disconnected;

the induction table 31 acquires the position information of the circuit breaking position, and the image device 45 shoots and archives the damaged position of the film;

the coiling roller 22 and the conveying wheel set 23 synchronously rotate to enable the next part to be detected of the film to enter the detection mechanism 3, the coiling roller 22 receives the detected film, the force measuring module 221 detects the pulling force at two ends when the coiling roller 22 is received, and adjusts the rotating speed of the conveying wheel set 23 at two sides of the film in real time to enable the film not to transversely shift when moving;

the background system calculates the marking position and the marking time according to the position information of the circuit disconnection and the rotation speed of the conveying wheel set 23, the sliding assembly 43 moves the marking head 44 to the position above the marking position in advance according to the data calculated by the background system, and after the marking time, the marking head 44 sprays the color paint to mark the damaged position of the film.

The foregoing has described the general principles, essential features, and advantages of the application. It will be understood by those skilled in the art that the present application is not limited to the embodiments described above, which are merely illustrative of the principles of the application, but that various changes and modifications may be made without departing from the spirit and scope of the application, and these changes and modifications are intended to be within the scope of the application as claimed. The scope of protection claimed by this application is defined by the following claims and their equivalents.

Claims

1. A film flaw detection device is characterized in that: comprises a frame, a conveying mechanism and a detection mechanism;

2. The apparatus of claim 1, wherein: the response platform is including response roof and response otter board, from last response roof, response otter board, film and the air current seat of setting gradually extremely down in the detection mechanism, the equidistant range in below of response roof is provided with a plurality of response posts, response post department slides from top to bottom and is provided with the current conducting plate, a plurality of fixed meshes have evenly been seted up on the response otter board, the distribution all around of fixed mesh has the conducting strip, the response otter board be provided with all around in the conductive head that the conducting strip is connected, the cooperation of response post is installed extremely in the fixed mesh, the current conducting plate when static with the conducting strip switches on, the current conducting plate be suitable for by the air current that film flaw department appears blow and with conducting strip off-connection.

3. The apparatus of claim 2, wherein: the main body shape of the conductive plate is cross-shaped, independent conductive circuits are arranged on the conductive plate in the longitudinal direction and the transverse direction, and the conductive circuits are suitable for being respectively connected with the conductive plates in the longitudinal direction and the transverse direction.

4. The apparatus of claim 2, wherein: the air flow seat is uniformly provided with a plurality of air inlets at the periphery, a plurality of air outlets communicated with the air inlets are arranged above the air flow seat at equal intervals, a constant pressure cavity is arranged in the air flow seat and is respectively communicated with the air inlets and the air inlets, the ratio of the total area of the air inlets to the total area of the air outlets is alpha, and alpha is more than or equal to 1.4 and less than or equal to 1.6.

5. The apparatus of claim 4, wherein: the end part of the induction column is conical, the gas outlet is provided with an injection pipe, and the injection pipe and the induction column are matched one by one.

6. The apparatus of claim 1, wherein: still include marking mechanism, marking mechanism includes guide rail, motor, slip subassembly and mark head, the guide rail transversely set up in the film top of detection mechanism's ejection of compact side, slip subassembly slidable set up in on the guide rail, mark head detachable set up in on the slip subassembly, the motor is used for control slip subassembly's slip, slip subassembly include transmission wheelset and pulley, one side of guide rail is provided with connects the tooth, transmission wheelset with guide rail rack and pinion connects, the opposite side of guide rail is provided with the sliding tray, the pulley sets up in the sliding tray, and the cooperation transmission wheelset centre gripping the guide rail.

7. The apparatus of claim 6, wherein: the marking mechanism further comprises an imaging device, the imaging device is arranged in the detection mechanism, and the imaging device is used for shooting a film photo at the position where the airflow appears.

8. The apparatus of claim 1, wherein: the conveying mechanism comprises a feeding roller, a coiling roller and a conveying wheel set, the feeding roller and the coiling roller are arranged at two ends of the rack, the conveying wheel set is arranged at two sides of the rack and comprises a first conveying wheel and a second conveying wheel, the first conveying wheel and the second conveying wheel are matched with each other to clamp a film, and the first conveying wheel and the second conveying wheel are suitable for enabling the film to move towards the coiling roller.

9. The apparatus of claim 8, wherein: the conveying wheel set is arranged on the periphery of the detection mechanism, the conveying wheel set is matched with and tensioned with the film in the detection mechanism, force measuring modules are arranged at two ends of the winding roller and are suitable for detecting the pulling force at two ends of the winding roller, and therefore the rotating speed of the conveying wheel set on two sides of the rack is controlled.

10. A method for detecting a defect in a thin film, comprising the steps of: