Automatic cover turning machine for paperboard book

Abstract

The utility model relates to a paperboard book automatic cover turning machine which comprises a rack, a paperboard book composed of a cover and a paper core is arranged on the rack in a sliding mode, supporting frames are arranged on the two opposite sides of the rack, a conveying mechanism and a turning mechanism are arranged on the rack, and the conveying mechanism drives the paperboard book to move in the length direction of the supporting frames. The turnover mechanism comprises an inclined plate and a push roller which are sequentially arranged in the paperboard book conveying direction, the inclined plate is arranged on the side wall of the rack and inclines upwards in the paperboard book conveying direction, the push roller is slidably connected to the rack, and a first air cylinder used for driving the push roller to move is arranged on the outer side wall of the rack. Automatic operation of the paperboard book cover turning process is achieved through cooperation of the conveying mechanism and the cover turning mechanism, manual operation is not needed in the whole cover turning process, and time and labor are saved. The paperboard book production device has the effect of improving the paperboard book production efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of board book production equipment, in particular to an automatic board book cover turning machine. BACKGROUND

[0002] A board book is a board book using thicker paperboard as book page and cover material, generally including a cover and a book core. The board book is more rigid and wear-resistant than the ordinary paperboard book, and can provide better structural stability and durability, so the board book is usually used in the field of children's books, picture books or publications requiring additional durability.

[0003] In the production process of the existing board book, the paperboard constituting the board book is fixed together by gluing to form a solid whole, but the cover of the glued paperboard book is usually in an open flat state, so before the paperboard book is packaged and transported, a cover turning process is needed to attach the cover to the paper core to ensure that the board book is in a folded state. The current cover turning process is mostly done by workers turning the cover to attach it to the surface of the paper core, but the number of board book production is large, and manual cover turning will consume a lot of time, thus resulting in low production efficiency of the board book, which has obvious deficiencies. CONTENT OF THE INVENTION

[0004] In order to improve the production efficiency of the board book, the present application provides an automatic board book cover turning machine.

[0005] The automatic board book cover turning machine provided by the present application adopts the following technical solution:

[0006] An automatic board book cover turning machine, comprising a rack, a board book composed of a cover and a paper core is slidably arranged on the rack, support frames are arranged on opposite sides of the rack, the length direction of the support frame is parallel to the length direction of the rack, a conveying mechanism and a cover turning mechanism are arranged on the rack, the conveying mechanism drives the board book to move along the length direction of the support frame, the cover turning mechanism comprises an inclined plate and a push roller arranged in sequence along the conveying direction of the board book, the inclined plate is arranged on the side wall of the rack, the inclined plate is inclined upward along the conveying direction of the board book, the push roller is slidably connected to the rack, the moving direction of the push roller is perpendicular to the length direction of the rack, and a first air cylinder for driving the push roller to move is arranged on the outer side wall of the rack.

[0007] By adopting the technical scheme, the paperboard book is moved to the support frame of the rack after being glued, the conveying mechanism conveys the paperboard book, and the cover of the paperboard book is gradually turned up under the guidance of the inclined surface of the inclined plate during the conveying of the paperboard book, and the included angle between the cover and the book core gradually decreases. When the paperboard book moves to the push roller, the push roller abuts against the outer surface of the cover, the first air cylinder is started to drive the push roller to move towards the support frame, and the push roller pushes the cover against the paper core during the movement, and the turning cover process of the paperboard book is completed. Therefore, the automatic operation of the turning cover process of the paperboard book is realized, manual operation is not required during the whole turning cover process, time and labor are saved, and the production efficiency of the paperboard book is improved.

[0008] Optionally, the conveying mechanism comprises a conveying plate slidingly arranged in the rack, a first push block and a second push block are arranged on the surface of the conveying plate, first rodless air cylinders are arranged on the opposite inner side walls of the support frame, the length direction of the first rodless air cylinder is parallel to the length direction of the support frame, a plurality of second rodless air cylinders are arranged on the moving part of the first rodless air cylinder, the length direction of the second rodless air cylinder is perpendicular to the length direction of the support frame, and the end surface of the conveying plate is connected with the moving part of the second rodless air cylinder.

[0009] By adopting the technical scheme, during conveying, the second rodless air cylinder is started to drive the conveying plate to move upwards, the first push block is abutted against the end surface of the paperboard book to be turned over by the conveying plate, the second push block is abutted against the end surface of the paperboard book whose cover is turned over, then the first rodless air cylinder is started, the conveying plate is driven by the first rodless air cylinder to move towards the discharge end through the moving part, during the movement, the paperboard book to be turned over gradually approaches the push roller, and the paperboard book whose cover is turned over moves out of the rack. When the cover of the paperboard book to be turned over abuts against the push roller, the second rodless air cylinder is started again to drive the conveying plate to move downwards, at this time, the first push block is separated from the paperboard book, and the first rodless air cylinder is started to drive the conveying plate to move towards the feeding end, so as to convey the subsequent paperboard book. Therefore, the feeding and discharging of the paperboard book are simultaneously performed, and the production efficiency of the paperboard book is further improved.

[0010] Optionally, a mounting frame is arranged on the rack, two connecting frames are arranged on the mounting frame, a fixing plate is arranged on each connecting frame, a sliding groove is arranged on the opposite inner side walls of the connecting frame, the sliding groove is arranged obliquely, the two ends of the fixing plate are slidingly connected in the sliding groove, and a second air cylinder for driving the fixing plate to slide along the sliding groove is arranged on the outer side wall of the connecting frame. When the fixing plate moves to one end of the sliding groove close to the support frame, the end surface of the fixing plate abuts against the outer side wall of the paperboard book.

[0011] By adopting the technical scheme, before the push roller pushes the cover, the second cylinder is started to drive the fixed plate to gradually approach the paper book end face, when the fixed plate abuts on the paper book end face, the position of the paper book on the support frame is fixed, so the setting realizes the fixation of the paper book, reduces the occurrence of the position deviation of the paper book under the push force of the push roller and the pressure of the pressing plate, and guarantees the smooth progress of the paper book cover turning process.

[0012] Optionally, the mounting frame is provided with a pressing frame, the pressing frame is provided with a pressing assembly, the pressing assembly comprises a third cylinder provided at the top end of the mounting frame, and an output shaft of the third cylinder is provided with a pressing plate, and the pressing plate is vertically and slidingly arranged on the mounting frame.

[0013] By adopting the technical scheme, after the cover of the paper book is combined with the paper core, the third cylinder is started to drive the pressing plate to move downward, the pressing plate generates downward pressure on the cover in the process of moving downward, the cover is combined with the paper core more tightly and firmly under the action of the pressure, meanwhile, the glue between the cover and the paper core can be fully distributed and solidified in the pressing process, and the structural stability of the paper book as a whole is improved.

[0014] Optionally, the mounting frame is provided with a mounting plate on the side close to the feeding end of the rack, a plurality of grooves are equidistantly formed at the bottom end of the mounting plate, a pressing assembly is arranged in the grooves, the pressing assembly comprises a sliding shaft arranged in the groove, a pressing wheel is rotatably connected to the outer surface of the sliding shaft, a limiting groove is formed in the opposite inner side walls of the groove, both ends of the sliding shaft are slidingly connected in the limiting groove, a spring is arranged in the limiting groove, one end of the spring is connected to the inner side wall of the limiting groove, and the other end of the spring is connected to the sliding shaft.

[0015] By adopting the technical scheme, in the conveying process of the paper book, a plurality of pressing wheels jointly press the surface of the paper core, the deviation of the paper book in the conveying process is reduced under the action of the pressure of the pressing wheels, and when the thickness of the paper core of the paper book changes, the sliding shaft moves up and down along the limiting groove under the action of the spring force, so as to press the paper core of different thicknesses.

[0016] Optionally, the feeding end of the rack is provided with a transition assembly corresponding to the support frame, the transition assembly comprises two conveying wheels rotatably connected to the outer side walls of the support frame, and a conveying belt is jointly sleeved on the outer surfaces of the conveying wheels.

[0017] By adopting the technical scheme, when the paper book is transferred from the gluing equipment to the support frame, the paper book passes through the transition assembly first, the setting of the transition assembly can smoothly transfer the paper book to the support frame, avoids the possibility that the paper book is turned up in the conveying process due to the height difference between the gluing equipment and the support frame, and thus improves the conveying stability.

[0018] Optionally, the pressing plate is provided with a rubber pad close to the surface of the support frame.

[0019] By adopting the above technical scheme, the rubber pad plays a buffering role on the pressure of the pressing plate on the paper book, reducing the possibility of damage to the paper book by instantaneous pressure.

[0020] Optionally, the surface of the support frame in contact with the paper book is coated with polytetrafluoroethylene.

[0021] By adopting the above technical scheme, the setting of polytetrafluoroethylene reduces the friction between the paper book and the surface of the support frame, allowing the paper book to be smoothly conveyed on the support frame.

[0022] In summary, the present application includes at least one of the following beneficial technical effects:

[0023] 1. The present application sets a conveying mechanism and a turning mechanism, and realizes the automatic operation of the paper book cover turning process through the cooperation of the conveying mechanism and the turning mechanism. The entire cover turning process does not need manual operation, saving time and effort, and improving the production efficiency of the paper book.

[0024] 2. The present application sets a pressing assembly, which plays a limiting role on the paper book in the conveying process, reducing the possibility of deviation of the paper book in the conveying process. At the same time, under the action of the spring force, the sliding shaft moves up and down along the limiting groove to realize the pressing of paper cores of different thicknesses. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 is a structural schematic diagram of the present application.

[0026] Figure 2 is a structural schematic diagram of the conveying mechanism and the turning mechanism in the embodiment of the present application.

[0027] Figure 3 is a schematic diagram of the position of the pressing assembly and the connecting frame on the mounting frame in the embodiment of the present application.

[0028] Figure 4 is a sectional view of the mounting plate in the embodiment of the present application.

[0029] Figure 5 is Figure 4 is an enlarged view of A in

[0030] Explanation of reference signs: 01, paper book; 011, paper core; 012, cover; 1, rack; 2, support frame; 3, transition assembly; 31, conveying wheel; 32, conveying belt; 4, conveying mechanism; 41, conveying plate; 42, first push block; 43, second push block; 44, first rodless air cylinder; 45, second rodless air cylinder; 5, cover turning mechanism; 51, inclined plate; 52, push roller; 53, first air cylinder; 6, mounting frame; 61, connecting frame; 62, pressing frame; 63, mounting plate; 71, fixed plate; 72, sliding groove; 73, second air cylinder; 8, pressing assembly; 81, third air cylinder; 82, pressing plate; 9, rubber pad; 10, groove; 101, limiting groove; 11, pressing assembly; 111, sliding shaft; 112, pressing wheel; 113, spring. DETAILED DESCRIPTION

[0031] The following will be described in detail below with reference to the accompanying drawings. Figures 1-5 The application is further described in detail.

[0032] The paper book automatic cover turning machine is disclosed.

[0033] Reference Figure 1 and Figure 2 The paper book automatic cover turning machine comprises a rack 1, the feeding end of the rack 1 is communicated with the discharging end of a paper book adhesive binding device, support frames 2 are arranged on opposite sides of the rack 1, and a paper book 01 is slidably connected on the two support frames 2. The paper book 01 is composed of a cover 012 and a paper core 011. The surface of the support frame 2 in contact with the paper book 01 is coated with polytetrafluoroethylene to reduce the friction when the paper book 01 slides. The length direction of the support frame 2 is parallel to the length direction of the rack 1. The feeding end of the rack 1 is provided with transition assemblies 3 corresponding to the support frames 2. The transition assembly 3 comprises two conveying wheels 31 rotatably connected to the outer side walls of the support frames 2, and the outer surfaces of the two conveying wheels 31 are jointly sleeved with a conveying belt 32.

[0034] The conveying belt 32 is moved in the process of rotation of the conveying wheels 31. When the paper book 01 bound by adhesive moves to the feeding end of the rack 1, the paper book 01 is stably moved to the surface of the support frame 2 under the conveying guiding action of the conveying belt 32, and is ready for the subsequent cover turning process. The arrangement of the transition assembly 3 can smoothly transfer the paper book 01 to the support frame 2, avoiding the possibility of the paper book 01 being turned up in the conveying process due to the height difference between the adhesive binding device and the support frame 2, thereby improving the conveying stability.

[0035] Reference Figure 1 and Figure 2, the rack 1 is provided with a conveying mechanism 4 and a turning mechanism 5, the conveying mechanism 4 comprises a conveying plate 41 slidingly arranged on the rack 1, the conveying plate 41 is sequentially and fixedly connected with a first push block 42 and a second push block 43 along the conveying direction of the paper book 01, the opposite inner side walls of the two support frames 2 are both fixedly installed with a first rodless air cylinder 44, the length direction of the first rodless air cylinder 44 is parallel to the length direction of the support frame 2, a plurality of second rodless air cylinders 45 are fixedly connected to the moving part of the first rodless air cylinder 44, in the embodiment, the number of the second rodless air cylinders 45 is three, the three second rodless air cylinders 45 are equidistantly and uniformly distributed, the length direction of the second rodless air cylinder 45 is perpendicular to the length direction of the support frame 2, the first rodless air cylinder 44 is used for realizing the lifting of the conveying plate 41 in the horizontal direction, and the second rodless air cylinder 45 is used for realizing the lifting of the conveying plate 41 in the vertical direction.

[0036] With reference to Figure 1 And Figure 2 , the turning mechanism 5 comprises an inclined plate 51 and a push roller 52 which are sequentially arranged along the conveying direction of the paper book 01, the inclined plate 51 is fixedly connected to the inner side wall of the rack 1 near one end of the cover 012, when the conveying mechanism 4 drives the paper book 01 to move to the bottom end of the inclined plate 51, the surface of the inclined plate 51 is attached to the outer surface of the cover 012, the inclined plate 51 is inclined upward along the conveying direction of the paper book 01, the push roller 52 is slidingly connected to the rack 1, the moving direction of the push roller 52 is perpendicular to the length direction of the rack 1, a first air cylinder 53 is fixedly connected to the outer side wall of the rack 1, and the output shaft of the first air cylinder 53 is fixedly connected to the center of the push roller 52.

[0037] When the paper book 01 moves to the support frame 2, the second rodless air cylinder 45 is started to drive the conveying plate 41 to move upward, the conveying plate 41 drives the first push block 42 to abut against the end face of the paper book 01 to be turned, then the first rodless air cylinder 44 is started, the first rodless air cylinder 44 drives the conveying plate 41 to move towards the discharge end through the moving part, in the process of moving of the paper book 01, the cover 012 is gradually turned upward under the guide of the inclined surface of the inclined plate 51, the included angle between the cover 012 and the book core gradually becomes smaller, when the paper book 01 moves to the push roller 52, the push roller 52 abuts against the outer surface of the cover 012, at this time, the second rodless air cylinder 45 and the first air cylinder 53 are synchronously started, the second rodless air cylinder 45 drives the conveying plate 41 to move downward, the first push block 42 is separated from the paper book 01, the first air cylinder 53 drives the push roller 52 to move towards the direction of the support frame 2, the push roller 52 pushes and presses the cover 012 on the paper core 011 when moving, and the cover turning process of the paper book 01 is completed.

[0038] After the paperboard book 01 cover turning process is completed, the first rodless cylinder 44 drives the conveying plate 41 to move towards the feeding end, when the first push block 42 moves to the new paperboard book 01 to be turned, the second rodless cylinder 45 drives the conveying plate 41 to move downwards, at this time the first push block 42 abuts on the new paperboard book 01, the second push block 43 abuts on the paperboard book 01 which has been turned, then the first rodless cylinder 44 drives the conveying plate 41 to move towards the discharging end, in the moving process, the paperboard book 01 to be turned gradually approaches the push roller 52 to prepare for the turning process, the paperboard book 01 which has been turned moves out of the rack 1, so the setting realizes the automatic operation of the paperboard book 01 cover turning process, the whole cover turning process does not need manual operation, saves time and effort, and the production efficiency of the paperboard book is improved.

[0039] With reference to Figure 3 and Figure 4 The rack 1 is fixedly installed with a mounting frame 6, two connecting frames 61 are detachably connected on the mounting frame 6 through bolts, a fixed plate 71 is arranged in each connecting frame 61, a sliding groove 72 is formed on the opposite inner side wall of the connecting frame 61 and is inclined downward along the length direction of the connecting frame 61, the two ends of the fixed plate 71 are slidingly connected in the sliding groove 72, a second cylinder 73 is arranged on the outer side wall of the connecting frame 61, the output shaft of the second cylinder 73 is fixedly connected on the fixed plate 71, when the fixed plate 71 moves to the end of the sliding groove 72 close to the support frame 2, the end face of the fixed plate 71 abuts on the end face of the paperboard book 01.

[0040] Before the push roller 52 pushes the cover 012, the second cylinder 73 is started, the second cylinder 73 is started to drive the fixed plate 71 to move along the sliding groove 72, the fixed plate 71 gradually approaches the end face of the paperboard book 01, when the fixed plate 71 abuts on the end face of the paperboard book 01, the position of the paperboard book 01 on the support frame 2 is fixed, so the setting realizes the fixation of the paperboard book 01, reduces the occurrence of the position deviation of the paperboard book 01 when it is subjected to the pushing force of the push roller 52, and guarantees the smooth progress of the cover turning process of the paperboard book 01.

[0041] With reference to Figure 3 and Figure 4The mounting rack 6 is fixedly installed with a pressing frame 62, the pressing frame 62 is in a door type, the length direction of the pressing frame 62 is perpendicular to the length direction of the mounting rack 6, the pressing frame 62 is provided with a pressing assembly 8, the pressing assembly 8 comprises a third air cylinder 81 fixedly installed at the top end of the pressing frame 62, the output shaft of the third air cylinder 81 is fixedly connected with a pressing plate 82, the pressing plate 82 is vertically and slidingly connected on the pressing frame 62, the end face of the pressing plate 82 facing the support frame 2 is fixedly connected with a rubber pad 9, so as to buffer the instantaneous pressure received by the paper book 01, after the cover 012 of the paper book 01 is combined on the paper core 011, the third air cylinder 81 is started to drive the pressing plate 82 to move downward, the pressing plate 82 generates downward pressure on the cover 012, and the cover 012 is combined with the paper core 011 more tightly and firmly under the action of the pressure.

[0042] With reference to Figure 4 and Figure 5 The mounting rack 6 is fixedly connected with a mounting plate 63 close to the feeding end of the rack 1, a plurality of grooves 10 are uniformly and equidistantly formed in the bottom end of the mounting plate 63, a pressing assembly 11 is arranged in the groove 10, the pressing assembly 11 comprises a sliding shaft 111 slidingly connected in the groove 10, a pressing wheel 112 is rotatably connected to the outer surface of the sliding shaft 111, a limiting groove 101 is formed in the opposite inner side wall of the groove 10, both ends of the sliding shaft 111 extend into the limiting groove 101, the limiting groove 101 is vertically arranged, a spring is arranged in the limiting groove 101, one end of the spring is connected to the inner side wall of the limiting groove 101, and the other end of the spring is fixedly connected to the sliding shaft 111, and in the natural state of the spring, the sliding shaft 111 abuts against the end face of the limiting groove 101 close to the support frame 2.

[0043] During the conveying of the paper book 01, the plurality of pressing wheels 112 jointly press against the surface of the paper core 011, and under the action of the pressure of the pressing wheels 112, the deviation of the paper book 01 during the conveying is reduced, and when the thickness of the paper core 011 of the paper book 01 changes, the sliding shaft 111 moves up and down along the limiting groove 101 under the action of the spring force, so as to press against the paper core 011 with different thicknesses.

[0044] The implementation principle of the automatic cover turning machine for paperboard books is as follows: the paperboard book 01 is moved to the support frame 2 of the rack 1 after being glued, the conveying mechanism 4 conveys the paperboard book 01, in the conveying process of the paperboard book 01, the cover 012 of the paperboard book 01 is gradually turned up under the guidance of the inclined surface of the inclined plate 51, the included angle between the cover 012 and the book core gradually decreases, when the paperboard book 01 moves to the push roller 52, the push roller 52 abuts against the outer surface of the cover 012, the first air cylinder 53 drives the push roller 52 to move towards the support frame 2, the push roller 52 pushes the cover 012 on the paper core 011 when moving, the cover turning process of the paperboard book 01 is completed, the automatic operation of the cover turning process of the paperboard book 01 is realized by the above setting, manual operation is not needed in the whole cover turning process, time and labor are saved, and the production efficiency of the paperboard book 01 is improved.

[0045] The above are preferred embodiments of the present application, and are not intended to limit the protection scope of the present application, therefore: any equivalent changes made on the structure, shape and principle of the present application shall be covered within the protection scope of the present application.

Claims

1. A paper book automatic cover turning machine, comprising a frame (1), a paper book (01) composed of a cover (012) and a paper core (011) is slidably arranged on the frame (1), characterized in that, The rack (1) is provided with support frames (2) on opposite sides, the length direction of the support frame (2) is parallel to the length direction of the rack (1), the rack (1) is provided with conveying mechanism (4) and turnover mechanism (5), the conveying mechanism (4) drives the paper book (01) to move along the length direction of the support frame (2), the turnover mechanism (5) includes inclined plate (51) and push roller (52) arranged in turn along the conveying direction of the paper book (01), the inclined plate (51) is arranged on the side wall of the rack (1), the inclined plate (51) is inclined upward along the conveying direction of the paper book (01), the push roller (52) is slidingly connected on the rack (1), the moving direction of the push roller (52) is perpendicular to the length direction of the rack (1), the outer side wall of the rack (1) is provided with first cylinder (53) for driving the push roller (52) to move.

2. A paper book automatic cover turning machine according to claim 1, characterized in that, The conveying mechanism (4) includes a conveying plate (41) slidingly arranged in the rack (1), the conveying plate (41) is provided with a first push block (42) and a second push block (43) on the surface, the opposite inner side walls of the support frame (2) are provided with a first rodless cylinder (44), the length direction of the first rodless cylinder (44) is parallel to the length direction of the support frame (2), a plurality of second rodless cylinders (45) are arranged on the moving part of the first rodless cylinder (44), the length direction of the second rodless cylinder (45) is perpendicular to the length direction of the support frame (2), and the end surface of the conveying plate (41) is connected with the moving part of the second rodless cylinder (45).

3. A paper book automatic cover turning machine according to claim 1, characterized in that, The rack (1) is provided with a mounting frame (6), the mounting frame (6) is provided with two connecting frames (61), each connecting frame (61) is provided with a fixed plate (71), the opposite inner side walls of the connecting frame (61) are provided with a sliding groove (72), the sliding groove (72) is inclined, the both ends of the fixed plate (71) are slidingly connected in the sliding groove (72), and the outer side wall of the connecting frame (61) is provided with a second cylinder (73) for driving the fixed plate (71) to slide along the sliding groove (72), when the fixed plate (71) moves to one end of the sliding groove (72) close to the support frame (2), the end surface of the fixed plate (71) abuts against the outer side wall of the paper book (01).

4. A paper book automatic cover turning machine according to claim 3, characterized in that, The mounting frame (6) is provided with a pressing frame (62), the pressing frame (62) is provided with a pressing assembly (8), the pressing assembly (8) includes a third cylinder (81) arranged at the top end of the mounting frame (6), the output shaft of the third cylinder (81) is provided with a pressing plate (82), and the pressing plate (82) is vertically slidingly arranged on the mounting frame (6).

5. A paper book automatic cover turning machine according to claim 3, characterized in that, The mounting frame (6) is provided with a mounting plate (63) near one side of the feeding end of the rack (1), a plurality of grooves (10) are equidistantly arranged at the bottom end of the mounting plate (63), a pressing assembly (11) is arranged in the grooves (10), the pressing assembly (11) comprises a sliding shaft (111) arranged in the groove (10), a pressing wheel (112) is rotatably connected to the outer surface of the sliding shaft (111), a limiting groove (101) is arranged on the opposite inner side wall of the groove (10), the two ends of the sliding shaft (111) are slidably connected in the limiting groove (101), a spring is arranged in the limiting groove (101), one end of the spring is connected to the inner side wall of the limiting groove (101), and the other end of the spring is connected to the sliding shaft (111).

6. A paper book automatic cover turning machine according to claim 1, characterized in that, The feeding end of the rack (1) is provided with a transition assembly (3) corresponding to the support frame (2), the transition assembly (3) comprises two conveying wheels (31) rotatably connected to the outer side wall of the support frame (2), and the outer surfaces of the conveying wheels (31) are jointly sleeved with a conveying belt (32).

7. A paper book automatic cover turning machine according to claim 4, characterized in that, The pressing plate (82) is provided with a rubber pad (9) near the surface of the support frame (2).

8. A paper book automatic cover turning machine according to claim 1, characterized in that, The surface of the support frame (2) in contact with the paper book (01) is coated with polytetrafluoroethylene.

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