CN213833801U

CN213833801U - Conveying paper pressing mechanism for printing machine

Info

Publication number: CN213833801U
Application number: CN202022361048.9U
Authority: CN
Inventors: 鲁保成; 邓燕
Original assignee: Nanjing Gaode Color Printing Co ltd
Current assignee: Nanjing Gaode Color Printing Co ltd
Priority date: 2020-10-21
Filing date: 2020-10-21
Publication date: 2021-07-30
Anticipated expiration: 2030-10-21

Abstract

The application relates to a conveying nipper constructs for printing machine, comprises a workbench, be equipped with the conveyer belt on the workstation, the direction of transmission of conveyer belt is unanimous with paper feeding direction, be equipped with the mount on the workstation, be equipped with on the mount and press the paper subassembly, press the paper subassembly including pinch roller, first connecting piece and the buffer assembly that is used for preventing the paper wrinkle, the pinch roller rotates with first connecting piece to be connected, first connecting piece passes through the buffer assembly and is connected with the mount, the pinch roller extends to the conveyer belt surface. This application adds buffering subassembly between pinch roller and mount, has reduced the contact force of pinch roller with the paper contact, has both made this application press the paper respond well, plays the guard action to the paper again.

Description

Conveying paper pressing mechanism for printing machine

Technical Field

The application relates to the field of printing machines, in particular to a conveying paper pressing mechanism for a printing machine.

Background

A printing machine is a machine for printing characters and images, and generally comprises mechanisms such as plate loading, inking, stamping, paper feeding and the like. Before printing, an operator needs to convey paper into a printing machine, and because the paper for printing is usually thin, the paper can be tilted if meeting external resistance in the transportation process, and then characters or patterns printed on the surface of the paper are inclined and unclear, so that the printing quality of the paper is reduced. In order to reduce the occurrence of the situation of paper tilting, a paper pressing mechanism is often additionally arranged between an ink coating mechanism and a paper feeding mechanism in the related art.

In the correlation technique, chinese patent with publication number CN209411455U discloses a press paper mechanism of a printing press, which includes a base, a paper feeding table, a first support and a hold-down bolt, wherein the first support is connected with a plurality of paper pressing elastic bands, the paper pressing elastic bands are arranged in an arc shape, and during operation, the hold-down bolt supports the paper pressing elastic bands tightly, so that the paper feeding table is pressed tightly by the paper pressing elastic bands, and the hold-down action is performed on paper, thereby preventing the paper from tilting.

With respect to the related art among the above, the inventors consider that the following drawbacks exist: when the paper is fed, the paper pressing elastic block is in rigid contact with the paper, the contact force is large, and the paper pressing elastic belt can generate scratches on the surface of the paper in the paper conveying process, so that the printing quality is affected.

SUMMERY OF THE UTILITY MODEL

In order to optimize the technical problem that scratches can be generated on paper in the related art, the application provides a conveying paper pressing mechanism for a printing machine.

The application provides a conveying nipper constructs for printing machine adopts following technical scheme:

the application relates to a conveying nipper constructs for printing machine, comprises a workbench, be equipped with the conveyer belt on the workstation, the direction of transmission of conveyer belt is unanimous with paper feeding direction, be equipped with the mount on the workstation, be equipped with on the mount and press the paper subassembly, press the paper subassembly including pinch roller, first connecting piece and the buffer assembly that is used for preventing the paper wrinkle, the pinch roller rotates with first connecting piece to be connected, first connecting piece passes through the buffer assembly and is connected with the mount, the pinch roller extends to the conveyer belt surface.

By adopting the technical scheme, when the paper pressing machine works, paper is conveyed on the workbench along the feeding direction under the conveying action of the conveying belt, the pressing wheel rolls on the paper in the conveying process, so that the paper pressing effect is realized, the buffering assembly has a buffering effect on the pressing wheel, the contact force of the pressing wheel and the paper is reduced, and scratches cannot be left on the paper by the pressing wheel in the paper pressing process; the conveying nipper constructs slide mechanism of this application plays the cushioning effect to the pinch roller, has reduced the damage of this nipper to the paper, and in addition, this application rotates the contact through pinch roller and paper, has both realized pressing the paper effect, has reduced the static when contacting again, and then makes the printing process go on high-efficiently.

Optionally, the first connecting piece includes a support column and two support plates oppositely disposed on the surface of the support column, a rotating shaft is disposed between the two support plates, the pressing wheel is rotatably connected with the rotating shaft, the two ends of the rotating shaft penetrate through the support plates, the support plates are provided with fixing nuts, and the two ends of the rotating shaft are both in threaded connection with the fixing nuts.

By adopting the technical scheme, during installation, an installer firstly rotatably connects the pressing wheel with the rotating shaft, then rotatably connects the rotating shaft between the two supporting support plates, and finally fixes the rotating shaft between the two supporting support plates through the fixing nut; fixation nut and pivot threaded connection, when the pinch roller broke down in the use, the operator can follow two blocks with the pinch roller and support and dismantle between the extension board, the change of being convenient for, convenient and practical.

Optionally, the buffer assembly comprises a limit ring plate, a spring and a sleeve, the limit ring plate is fixedly connected to the outer peripheral wall of the support column, the spring is sleeved on the support column, one end of the spring is abutted against the limit ring plate, the other end of the spring is connected with the inner bottom wall of the sleeve, the support column is connected with the sleeve in a sliding mode, and the sleeve is fixedly connected with the fixing frame.

By adopting the technical scheme, when the paper pressing device is used, the pressing wheel is abutted to paper, the sleeve is fixed by the fixing frame to compress the spring, the compressed spring has a resetting trend, one end of the compressed spring abuts against the limiting ring plate, and the pressing wheel abuts against the paper; the spacing ring plate, the spring and the sleeve are matched, so that the contact force of the pinch roller and the paper is effectively buffered, and the paper is protected to a greater extent.

Optionally, the buffering assembly comprises an elastic arc piece, a supporting plate and a fastening bolt for fastening the elastic arc piece, one end of the elastic arc piece is fixedly connected with the supporting column, the other end of the elastic arc piece is fixedly connected with the fixing frame, one end of the supporting plate is fixedly connected with the fixing frame, the other end of the supporting plate extends to the paper feeding direction, one end of the fastening bolt is in threaded connection with the supporting plate, and one end of the fastening bolt, which penetrates out of the supporting plate, is abutted against the elastic arc piece.

By adopting the technical scheme, when the paper pressing device is used, paper is abutted to the pressing wheel, one end of the elastic arc piece is bent under the fixing action of the fixing frame, elasticity is stored, the other end of the elastic arc piece abuts against the pressing wheel, so that the pressing wheel abuts against the paper, in addition, an operator can control the bending degree of the elastic arc piece by adjusting the abutting bolt, and the abutting degree of the pressing wheel against the paper is adjusted; the elastic arc piece, the abutting bolt and the supporting plate are matched, so that an operator can adjust the abutting degree of the pressing wheel to paper according to different printing products or printing environments, and the conveying paper pressing mechanism is suitable for different printed matters.

Optionally, the mount is including the loop bar that slides, the length direction perpendicular to paper feed direction of the loop bar that slides, the loop bar that slides passes through the gear assembly and connects on the wall with workstation both sides, the buffering subassembly is connected with the loop bar that slides.

Through adopting above-mentioned technical scheme, the perpendicular paper feeding direction of loop bar that slides sets up, and the buffering subassembly of being convenient for sets up along paper feeding direction to make the pinch roller can roll by paper feeding direction, reduced the frictional force between pinch roller and the paper to a great extent.

It is optional, the loop bar that slides includes connecting cylinder, dwang and butterfly bolt, the dwang rotates to be connected in the connecting cylinder, the connecting cylinder is stretched out at the dwang both ends, butterfly bolt and connecting cylinder threaded connection, the butterfly bolt stretches into the one end of connecting cylinder and supports tight dwang lateral wall, vertical protrusion is equipped with the fixed plate on the both sides wall of workstation along paper feed direction, the loop bar that slides is connected between two fixed plates, the dwang slides with the fixed plate and is connected, the dwang is close to the equal fixedly connected with rolling disc of lateral wall at both ends.

Through adopting above-mentioned technical scheme, when printing paper size changed, the operator need change the position of pinch roller for keep away from the juncture of two papers of pinch roller butt of feeding one side, in order to avoid keeping away from the paper perk of feeding one side.

When the printing size changes, the operator at first unscrews the butterfly bolt for connecting cylinder and dwang can rotate relatively, and the operator rotates the rolling disc afterwards, and the rolling disc drives the dwang and slides on the fixed plate and rotates, and connecting cylinder and dwang rotate and connect, make pinch roller, the buffering subassembly etc. of connecting on the connecting cylinder not along with dwang synchronous revolution, when the dwang slides along paper feeding direction, the pinch roller rolls at the workstation surface.

When the pinch roller rolled to two paper handing-over departments, the operator screwed up the butterfly bolt, rotated through connecting cylinder and slide bar and connected, and the operator can easily realize the translation of slip loop bar through rolling disc and fixed plate to realize the removal of pinch roller position, operation process is simple convenient, has increased this conveying nipper mechanism's application range.

Optionally, the outer wall of the connecting cylinder is provided with a paper pressing strip and a second connecting piece, one end of the paper pressing strip is connected with the outer wall of the connecting cylinder through the second connecting piece, and the other end of the paper pressing strip extends along the feeding direction of paper.

By adopting the technical scheme, when the paper pressing device is used, the paper pressing strip falls on paper and plays a paper pressing role by virtue of gravity, and the paper pressing strip has elasticity and lighter weight, so that the paper can not be damaged while a good paper pressing effect is achieved; the paper pressing strip further increases the paper pressing effect of the conveying paper pressing mechanism.

Optionally, the second connecting piece includes connection frame and fixing bolt, connection frame and fixing bolt threaded connection, the connection frame is worn to locate along self length direction by the connecting cylinder, the diapire of connecting cylinder and the diapire butt in the connection frame, press the paper strip to be located between connecting cylinder and the connection frame, the connection frame roof is worn to locate by fixing bolt, fixing bolt one end is worn out the connection frame roof and is supported and sticiss the paper strip.

By adopting the technical scheme, during installation, an operator firstly abuts against the groove wall of the connecting cylinder and the fixing groove far away from the fixing bolt, then one end of the paper pressing strip is placed on the connecting cylinder, then the fixing bolt is screwed, one end of the fixing bolt abuts against and presses the paper strip, the paper pressing strip is fixed in the fixing groove, and therefore the connecting block and the paper pressing strip are both fixed on the connecting cylinder; connecting block and fixing bolt cooperation for press the paper strip and can dismantle the change, convenient practicality.

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

1. the connecting cylinder of this application rotates with the dwang to be connected for the operator can be at the asynchronous pivoted condition translation loop bar that slides of pinch roller, and then makes the pinch roller of keeping away from feeding one side can compress tightly handing-over department of two papers.

2. This application can dismantle on the loop bar that slides and be connected with the pressure note, has further increased this conveying nipper's the effect of pressing paper.

3. The sliding sleeve and the fixing plate are meshed and connected, and the position of the pressing wheel can be changed conveniently, so that the paper pressing device is applicable to paper with different sizes.

Drawings

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

FIG. 2 is a partially exploded view of a slip stem used in embodiments embodying the present application.

Figure 3 is a partially exploded view of a paper pressing strip and a second connector for embodying embodiments of the present application.

Fig. 4 is an exploded view schematically showing the connection relationship between the rotating rod and the fixing plate in the embodiment of the present application.

FIG. 5 is an exploded view of a buffer assembly and a platen assembly in accordance with embodiment 1 of the present application

Fig. 6 is a schematic structural diagram of a buffer assembly used in embodiment 2 of the present application.

Description of reference numerals: 1. a work table; 11. a fixing plate; 111. a sliding groove; 112. a rack; 12. a limiting block; 121. a limiting groove; 122. mounting grooves; 2. a conveyor belt; 3. a fixed mount; 4. a paper pressing assembly; 41. a pinch roller; 42. a first connecting member; 421. a support pillar; 422. a support plate; 423. a rotating shaft; 424. fixing a nut; 425. connecting holes; 43. a buffer assembly; 431. a limit ring plate; 432. a spring; 433. a sleeve; 434. an elastic arc piece; 435. a support plate; 4351. a second threaded hole; 436. tightly abutting against the bolt; 5. a guide bar; 6. sliding the loop bar; 61. connecting the circular rings; 611. a connecting rod; 62. a connecting cylinder; 621. a first threaded hole; 622. pressing the paper strips; 623. a second connecting member; 6231. a connecting frame; 6232. fixing the bolt; 63. rotating the rod; 631. rotating the disc; 632. a gear; 64. butterfly bolt.

Detailed Description

The present application is described in further detail below with reference to figures 1-6.

The embodiment 1 of the application discloses a conveying paper pressing mechanism for a printing machine.

Example 1

Referring to fig. 1, the conveying paper pressing mechanism for the printing machine comprises a workbench 1, wherein a conveying belt 2 is arranged on the workbench 1, the conveying belt 2 has the same effect as a first conveying belt in the related technology, the conveying direction of the conveying belt 2 is the same as the paper feeding direction, and the upper surface of the conveying belt 2 is flush with the table board of the workbench 1, so that paper can be conveyed conveniently.

The worktable 1 is provided with a fixed frame 3, and the fixed frame 3 is provided with a paper pressing component 4 for preventing paper from wrinkling.

Referring to fig. 1 and 2, the fixing frame 3 includes a guide rod 5 and at least two sliding sleeve rods 6, the guide rod 5 is vertically connected with the sliding sleeve rods 6, and the length direction of the guide rod 5 is the same as the paper feeding direction.

Referring to fig. 1, two fixing plates 11 are oppositely arranged at the edge of a workbench 1, the length direction of the fixing plates 11 is the same as the paper feeding direction, the fixing plates 11 are vertically and fixedly connected with the workbench 1, and a sliding loop bar 6 is vertically connected between the two fixing plates 11.

Referring to fig. 1 and 2, the sliding sleeve rod 6 includes a connecting cylinder 62, a rotating rod 63 and a butterfly bolt 64 spanning between two fixing plates 11, the rotating rod 63 is rotatably connected in the connecting cylinder 62, the connecting cylinder 62 extends out of two ends of the rotating rod 63, a first threaded hole 621 is arranged on the side wall of the connecting cylinder 62 close to the end of the connecting cylinder 62, the butterfly bolt 64 is in threaded connection with the first threaded hole 621, and one end of the butterfly bolt 64 penetrates out of the first threaded hole 621 and abuts against the side wall of the rotating rod 63.

Referring to fig. 3, a paper pressing strip 622 and a second connecting piece 623 are connected to the outer peripheral wall of the connecting cylinder 62, the second connecting piece 623 comprises a connecting frame 6231 and a fixing bolt 6232, the connecting cylinder 62 penetrates through the connecting frame 6231 along the length direction of the connecting cylinder, the connecting frame 6231 wraps the outer peripheral wall of the connecting cylinder 62, one end of the paper pressing strip 622 is clamped between the upper inner wall of the connecting frame 6231 and the upper inner wall of the connecting cylinder 62, the fixing bolt 6232 is in threaded connection with the top wall of the connecting frame 6231, the fixing bolt 6232 penetrates through the top wall of the connecting frame 6231, one end of the fixing bolt 6232 penetrates through the top wall of the connecting frame 6231 and abuts against the paper pressing strip 622, and one end, far away from the connecting cylinder 62, of the paper pressing strip 622 is lapped on paper.

Referring to fig. 4, a sliding groove 111 is formed in the top wall of the fixed plate 11 along the self direction, a rack 112 is formed in the bottom wall of the sliding groove 111, a gear 632 is fixedly connected to the rotating rod 63, the gear 632 is meshed with the rack 112, rotating discs 631 are fixedly connected to the side walls of the rotating rod 63 near the two ends, and the gear 632 is located between the two rotating discs 631.

Referring to fig. 4, be equipped with the locating part on the fixed plate, the locating part includes stopper 12, and a wall of stopper 12 runs through and is equipped with the spacing groove 121 that is used for spacing dwang 63, runs through on the stopper 12 and is equipped with mounting groove 122, during the use, installs stopper 12 on fixed plate 11 for in fixed plate 11 card goes into the mounting groove 122, and dwang 63 card goes into spacing groove 121 simultaneously, and the locating part passes through the bolt fastening about two walls of mounting groove 122 symmetry.

Referring to fig. 5, the paper pressing assembly 4 includes a pressing wheel 41, a first connecting piece 42 and a buffering assembly 43, the first connecting piece 42 is connected with the connecting cylinder 62 through the buffering assembly 43, the first connecting piece 42 includes a supporting column 421 and two supporting support plates 422 arranged oppositely, one end of each supporting support plate 422 is welded to the bottom wall of the corresponding supporting column 421, a rotating shaft 42 and a fixing nut 424 are arranged between the pressing wheel 41 and the supporting support plates 422, a connecting hole 425 is arranged on each supporting support plate 422, one end of each rotating shaft 423 is arranged through one connecting hole 425 and is in threaded connection with the corresponding fixing nut 424, and the other end of each rotating shaft 423 is arranged through the other connecting hole 425 and is in threaded connection with the corresponding fixing nut 424; an operator may secure puck 41 by tightening retaining nut 424 and, in the event of a puck 41 failure, the operator may remove replacement puck 41 by loosening retaining nut 424.

Referring to fig. 5, the buffer assembly 43 includes a limit ring plate 431, a spring 432, a sleeve 433 and a connecting rod 611, the limit ring plate 431 is welded around the outer peripheral wall of the supporting column 421, the spring 432 is sleeved on the peripheral wall of the supporting column 421, one end of the spring 432 abuts against the upper surface of the limit ring plate 431, the other end of the spring 432 is fixedly connected with the inner bottom wall of the sleeve 433, the supporting column 421 is connected with the sleeve 433 in a sliding manner, the sliding sleeve rod 6 is fixedly connected with a connecting ring 61, one end of the connecting rod 611 is welded with the top of the sleeve 433, and the other end of the connecting rod 611 is welded perpendicularly to the connecting ring 61.

The implementation principle of the embodiment 1 is as follows:

when the paper feeding device works, under the transmission action of the conveyor belt 2, paper is transmitted between the pressing wheels 41 and the conveyor belt 2 along the feeding direction, in the transmission process, the pressing wheels 41 roll on the paper, and at least one pair of pressing wheels 41 are compacted at the junction of the two paper;

the operator can unscrew butterfly bolt 64, rotates connecting cylinder 62 along paper feeding direction again, and sleeve 433 and spacing ring plate 431 play the squeezing action to spring 432 this moment, and compressed spring 432 has the trend of reseing to support spacing ring plate 431, and then make pinch roller 41 support the paper, when the butt power of pinch roller 41 and paper reachd the work needs, the operator screws up butterfly bolt 64.

When the paper size of printing changes, the operator takes off stopper 12 to unscrew butterfly bolt 64, rotate rolling disc 631, make gear 632 on the dwang 63 roll on rack 112, thereby make the loop bar 6 that slides along the direction of feed translation, when pinch roller 41 and two paper junctures butt, screw up butterfly bolt 64, rethread stopper 12 fixes dwang 63 on fixed plate 11.

Example 2

Referring to fig. 6, the difference between this embodiment and embodiment 1 is that the buffering assembly 43 includes an elastic arc plate 434, a supporting plate 435, and a fastening bolt 436, one end of the elastic arc plate 434 is fixedly connected to the supporting column 421, the other end of the elastic arc plate 434 is fixedly connected to the fixing frame 3, one end of the supporting plate 435 is vertically and fixedly connected to the connecting ring 61, the other end of the supporting plate 435 extends in the paper feeding direction, a second threaded hole 4351 is formed in the supporting plate 435, one end of the fastening bolt 436 is in threaded connection with the second threaded hole 4351 and penetrates through the supporting plate 435, and one end of the fastening bolt 436 penetrating through the supporting plate 435 abuts against the elastic arc plate 434.

The implementation principle of the embodiment 2 is as follows: an operator can unscrew the butterfly bolt 64, and then tighten the fastening bolt 436 to increase the length of the fastening bolt 436 penetrating out of the second threaded hole 4351, so that the fastening degree of the fastening bolt 436 to the elastic arc piece 434 is increased, the elastic arc piece 434 has elasticity, bending is generated under the fastening of the fastening bolt 436, the butterfly bolt 64 is reset, the pressing wheel 41 is fastened to paper, and when the fastening force of the pressing wheel 41 and the paper reaches the working requirement, the butterfly bolt 64 is tightened by the operator.

The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.

Claims

1. The utility model provides a conveying nipper constructs for printing machine, includes workstation (1), its characterized in that: the utility model discloses a paper folding press, including workstation, (1) be equipped with conveyer belt (2) on the workstation, the transmission direction of conveyer belt (2) is unanimous with paper direction of feed, be equipped with mount (3) on workstation (1), be equipped with on mount (3) and press paper subassembly (4), press paper subassembly (4) including pinch roller (41), first connecting piece (42) and the buffer unit (43) that are used for preventing the paper wrinkle, pinch roller (41) rotate with first connecting piece (42) and are connected, first connecting piece (42) are connected with mount (3) through buffer unit (43), pinch roller (41) extend to conveyer belt (2) surface.

2. The transport platen mechanism for a printer according to claim 1, characterized in that: first connecting piece (42) are including support column (421) and two support extension board (422) of setting relatively on support column (421) surface, be equipped with pivot (423) between two support extension board (422), pinch roller (41) rotate with pivot (423) and be connected, support extension board (422) are worn to locate at pivot (423) both ends, be equipped with fixation nut (424) on support extension board (422), pivot (423) both ends all with fixation nut (424) threaded connection.

3. The transport platen mechanism for a printer according to claim 2, characterized in that: buffer unit (43) include spacing crown plate (431), spring (432) and sleeve (433), spacing crown plate (431) fixed connection is on support column (421) periphery wall, spring (432) cup joint on support column (421), spring (432) one end and spacing crown plate (431) butt, spring (432) other end and sleeve (433) inner bottom wall connection, support column (421) and sleeve (433) slide and are connected, sleeve (433) and mount (3) fixed connection.

4. The transport platen mechanism for a printer according to claim 2, characterized in that: the buffer assembly (43) comprises an elastic arc piece (434), a support plate (435) and a tightening bolt (436) used for tightening the elastic arc piece (434), one end of the elastic arc piece (434) is fixedly connected with the support column (421), the other end of the elastic arc piece (434) is fixedly connected with the fixing frame (3), one end of the support plate (435) is fixedly connected with the fixing frame (3), the other end of the support plate (435) extends to the paper feeding direction, one end of the tightening bolt (436) is in threaded connection with the support plate (435), and one end, penetrating out of the support plate (435), of the tightening bolt (436) is abutted to the elastic arc piece (434).

5. The transport platen mechanism for a printer according to claim 1, characterized in that: the fixing frame (3) comprises a sliding sleeve rod (6), the length direction of the sliding sleeve rod (6) is perpendicular to the paper feeding direction, the sliding sleeve rod (6) is connected to the two side walls of the workbench (1) through a gear assembly, and the buffering assembly (43) is connected with the sliding sleeve rod (6).

6. The transport platen mechanism for a printer according to claim 5, wherein: slide loop bar (6) including connecting cylinder (62), dwang (63) and butterfly bolt (64), dwang (63) are rotated and are connected in connecting cylinder (62), connecting cylinder (62) are stretched out at dwang (63) both ends, butterfly bolt (64) and connecting cylinder (62) threaded connection, butterfly bolt (64) stretch into the one end of connecting cylinder and support tight dwang (63) lateral wall, vertical protrusion is equipped with fixed plate (11) on the both sides wall of paper feeding direction is followed in workstation (1), slide loop bar (6) and connect between two fixed plates (11), dwang (63) slide with fixed plate (11) and be connected, the equal fixedly connected with rolling disc (631) of lateral wall that dwang (63) are close to both ends.

7. The transport platen mechanism for a printer according to claim 6, wherein: be equipped with on the outer wall of connecting cylinder (62) and press paper strip (622) and second connecting piece (623), press paper strip (622) one end to pass through second connecting piece (623) and connecting cylinder (62) outer wall connection, press paper strip (622) other end to extend along paper feed direction.

8. The transport platen mechanism for a printer according to claim 7, wherein: the second connecting piece (623) comprises a connecting frame (6231) and a fixing bolt (6232), the connecting frame (6231) is in threaded connection with the fixing bolt (6232), the connecting cylinder (62) penetrates through the connecting frame (6231) along the length direction of the connecting cylinder, the bottom wall of the connecting cylinder (62) is abutted to the inner bottom wall of the connecting frame (6231), the paper pressing strip (622) is located between the connecting cylinder (62) and the connecting frame (6231), the fixing bolt (6232) penetrates through the top wall of the connecting frame (6231), and one end of the fixing bolt (6232) penetrates through the top wall of the connecting frame (6231) and is abutted to the paper pressing strip (622).