CN109230745B

CN109230745B - Paper-feeding steady pictorial machine with electric control swing roller

Info

Publication number: CN109230745B
Application number: CN201810841662.XA
Authority: CN
Inventors: 李阳
Original assignee: Zhengzhou New Century Digital Technology Co ltd
Current assignee: Zhengzhou New Century Digital Technology Co ltd
Priority date: 2018-07-27
Filing date: 2018-07-27
Publication date: 2020-05-05
Anticipated expiration: 2038-07-27
Also published as: CN109230745A

Abstract

A portrait machine with an electric control swing roller for stable paper feeding comprises a rack, a printing body, a winding roller, a winding motor, an unwinding roller and an unwinding motor, wherein a front rotating roller is rotatably arranged on the rack below the front part of the printing body; the rear rotary roller is rotatably arranged on the frame below the rear part of the printing body, rear cranks are respectively arranged at two shaft ends of the rear rotary roller, a rear tension roller is hinged between the two rear cranks, and matched second proximity switches are arranged on the shaft end of the rear rotary roller and the frame at the shaft end. The printer with the stable paper feeding and the electric control swing roller has the advantages of scientific design, stable paper feeding, high structural strength, bending resistance and high paper feeding precision, and can avoid the tension roller from impacting a printing medium.

Description

Paper-feeding steady pictorial machine with electric control swing roller

Technical Field

The invention relates to the technical field of photo machines, in particular to a photo machine with an electric control swing roller and a stable paper feeding function.

Background

The printer is used in advertisement, graph and text and CAD industry and is one large format printer with various color patterns sprayed with nozzle onto special material. The printing medium is generally a soft film or special cloth or special roll paper, and in the printing process of the printer, the printing medium needs to stay on a printing platform for a certain time to match with an ink vehicle to drive a spray head to reciprocate on an ink vehicle track, so that the spray head can spray ink uniformly on the wide surface of the printing medium, therefore, the printing medium intermittently moves on the printing platform and moves to a winding end once by a certain length, while the traditional winding and unwinding roller system generally uniformly unwinds and winds at a set speed, so that the printing medium suddenly loosens within a time period each time in the unwinding and winding processes to bend and separate from the roller surface in the winding and unwinding roller system, the paper feeding is not stable, and the printing platform is easy to wrinkle when inputting and outputting the printing medium; in the prior art, a tension roller is additionally arranged in a take-up and pay-off roller system, the tension roller generally applies tension to a printing medium in a moving process by means of self gravity, although the printing medium can be kept in a tensioning state, the impact force of the tension roller on the printing medium in a vertical track movement is large, and the printing medium is easy to damage; the flatness of the upper surface and the lower surface of a printing platform of a common printer is not high, and bulges or pits are easy to appear locally, so that a printing medium generates an indentation after printing is finished; the leg structure of the existing printer is usually fixedly connected or directly welded only by bolts, so that the strength is not enough and the bending resistance is not high; the general back pendant and back pendant bearing structure are integrated into one piece's frame type structure section bar, and the outer terminal surface of back pendant is for propping the paper structure, easily receives the extrusion deformation when the paper feeding, causes the paper feeding precision to hang down.

In order to solve the above problems, people are always seeking an ideal technical solution.

Disclosure of Invention

The invention aims to overcome the defects of the prior art, and provides the printer which has the advantages of scientific design, stable paper feeding, high structural strength of a frame, bending resistance and high paper feeding precision, avoids the impact of a tension roller on a printing medium, and stably feeds the paper with the electric control swing roller.

In order to achieve the purpose, the invention adopts the technical scheme that: a printer with an electric control swing roller for stable paper feeding comprises a frame, a printing body, a winding roller, a winding motor, an unwinding roller and an unwinding motor, the printing body, the winding roller, the winding motor, the unwinding roller and the unwinding motor are respectively arranged on the rack, the winding motor drives the winding roller to rotate, the unwinding motor drives the unwinding roller to rotate, a front rotating roller is rotatably arranged on the machine frame at the front lower part of the printing body, front cranks with the same angle and direction are respectively arranged at two shaft ends of the front rotating roller, a front tension roller is hinged between the two front cranks, the front tension roller is arranged in parallel with the front rotating roller, two front limiting stop posts for limiting the front-back swing amplitude of the front crank are arranged on a frame at the end of the front rotating roller, a matched first proximity switch is arranged on the shaft end of the front rotating roller and the rack at the shaft end; a rear rotating roller which is symmetrical to the front rotating roller is rotatably arranged on a rack below the rear part of the printing body, rear cranks with the same angle and direction are respectively arranged at two shaft ends of the rear rotating roller, a rear tension roller is hinged between the two rear cranks and is arranged in parallel with the rear rotating roller, two rear limiting stop posts for limiting the front-rear swinging amplitude of the rear cranks are arranged on a rack at the shaft end of the rear rotating roller, and matched second proximity switches are arranged on the shaft end of the rear rotating roller and the rack at the shaft end; the rack is also provided with an electric cabinet, a power supply, a winding relay and an unwinding relay are arranged in the electric cabinet, and the power supply is respectively and electrically connected with the winding motor, the unwinding motor, the first proximity switch and the second proximity switch; the first proximity switch is electrically connected with the winding relay, the winding relay is electrically connected with the winding motor, when a probe of the first proximity switch detects an approach signal, the winding relay is triggered to control the winding motor to start, the winding roller rotates to wind, and when the probe of the first proximity switch does not detect the approach signal, the winding relay is triggered to control the winding motor to close; the second proximity switch is electrically connected with the unwinding relay, the unwinding relay is electrically connected with the unwinding motor, when a probe of the second proximity switch cannot detect an approaching signal, the unwinding relay is triggered to control the unwinding motor to be started, the unwinding roller rotates to unwind, and when the probe of the second proximity switch detects the approaching signal, the unwinding relay is triggered to control the unwinding motor to be turned off; the printing device comprises a printing body, a winding roller, an unwinding roller and a printing medium, wherein the printing body is provided with a printing medium, the winding roller and the unwinding roller are arranged on the printing body, and the winding length and the unwinding length are the same as the moving length.

Basically, print the body including horizontal two erect the square steel main part and the print platform on landing leg top, a plurality of printing support section bars are installed to the up end of square steel main part, the print platform assembly is in each upper end of printing the support section bar, print platform is integrated into one piece's aluminium alloy panel, the upper and lower surface of aluminium alloy panel mills through the milling machine and levels.

The printing machine comprises a machine frame, a printing body, a machine frame and a machine frame, wherein the machine frame comprises transverse support legs arranged on two sides of the printing body, vertical support legs assembled with the transverse support legs, a vertical plate and a cross beam, the vertical plate and the cross beam are installed on the outer side walls of the vertical support legs, the transverse support legs, the vertical support legs and the cross beam are all rectangular welded pipe fittings, the bottoms of the vertical support legs are vertically connected in the middle of the transverse support legs in a penetrating mode, corner plates are connected at the joints of the vertical support legs and the cross beam in a penetrating mode to fix the vertical support legs, two end portions of the cross beam are vertically connected in the middle of the vertical support legs in a penetrating mode, corner plates are connected at the joints of the cross beam and the vertical support legs to fix the cross beam, the bottom edges of the vertical plate are pressed on the upper planes of.

On the base, the wind-up roll is rotatably installed on the vertical plate at the front lower part of the printing body, the unreeling roll is rotatably installed on the vertical plate at the rear lower part of the printing body, and two reel stoppers are installed on the wind-up roll and the unreeling roll.

Based, print the body and still include the fixed subassembly of back pendant and back pendant, the back pendant is integrated into one piece's arc section bar, the arc angle of back pendant is less than 90, the fixed subassembly of back pendant is the fixed section bar of notch cuttype, the fixed subassembly assembly of back pendant is in the square steel main part, back pendant covers and installs on the fixed subassembly of back pendant.

Based, the fixed subassembly of back pendant supports the strengthening rib and becomes the back pendant backup pad of notch cuttype including the back pendant fixed plate, a plurality of back pendant of becoming the L type, back pendant backup pad includes inboard vertical board, middle horizontal board and the vertical board in the outside, inboard vertical board middle horizontal board with the vertical board integrated into one piece in the outside is the ladder section bar, the vertical board lower extreme integrated into one piece in the outside has U type hem, the interior riser upper end integrated into one piece of back pendant fixed plate has the right angle hem, back pendant fixed plate with the vertical butt joint of the vertical board in inboard, each back pendant supports the perpendicular fixed connection of strengthening rib equidistance back pendant fixed plate the lower terminal surface with the medial surface of the vertical board in inboard.

Basically, each back pendant supporting reinforcing rib and each printing supporting section bar are arranged in a staggered and parallel mode, the lower end face of a back pendant fixing plate is fixedly arranged on the upper end face of each back pendant supporting reinforcing rib, the inner side face of an inner side vertical plate is fixedly arranged on the outer side face of each printing supporting section bar, the lower end face of a middle transverse straight plate is in press connection with the upper surface of a square steel main body, the inner side face of an outer side vertical plate is in press connection with the outer side face of the square steel main body, the upper end of a back pendant is arranged on a right-angle folded edge of the back pendant fixing plate, the lower end of the back pendant is provided with a plurality of clamping grooves with downward openings, the lower end of the back pendant is assembled and clamped on a U-shaped folded edge of the outer side vertical plate through the clamping grooves, a paper feeding flat plate is integrally formed at the upper end of the back pendant, the edge of the paper feeding flat plate is in butt joint with the front edge of the printing platform, and the paper feeding flat plate is flush with the upper surface of the printing platform.

Compared with the prior art, the invention has outstanding substantive characteristics and remarkable progress, in particular to the invention, the front tension roller and the rear tension roller respectively swing back and forth around the front rotating roller and the rear rotating roller, a printing medium is moved out after jet printing is finished on the printing platform, and moves for a certain length in the winding roller direction once, the front tension roller presses the surface of the printing medium to swing forwards so as to prop flat the printing medium, the printing medium is prevented from bending and wrinkling and the winding quality is influenced, when the front tension roller swings forwards until the front crank abuts against the front limit stop post at the front end of the front rotating roller, the probe of the first proximity switch triggers the winding relay to control the winding motor to start, the winding roller rotates to wind the printed printing medium, when the probe of the first proximity switch does not detect the proximity signal, triggering the winding relay to control the winding motor to be closed; similarly, paper feeding and paper discharging at the rear end of the printing platform are synchronous, namely, when the printing medium finishes jet printing with a certain length, the unprinted printing medium moves to the printing platform with a certain length, the rear tension roller swings forwards under the driving of the printing medium to support the printing medium, so that the surface of the printing medium is flat when the printing medium enters the printing platform, meanwhile, the probe of the second proximity switch cannot detect a proximity signal, the unwinding relay is triggered to control the unwinding motor to start, the unwinding roller rotates to unwind, when the rear tension roller swings forwards until the orientation of the rear crank is upwards close to vertical, the probe of the second proximity switch detects the proximity signal, the unwinding relay is triggered to control the unwinding motor to close, and meanwhile, the movement of the printing medium on the printing body is finished; each rolling of the rolling roller and each rolling of the rolling roller are synchronous with each movement of the printing medium on the printing body, and the rolling length are the same as the moving length; so, can guarantee that the paper feed is steady, preceding tension roller with back tension roller props flat print media through the swing, has avoided forming great impact force to print media, not fragile print media.

Further, print platform is integrated into one piece's aluminium alloy panel, the upper and lower surface of aluminium alloy panel mills through the milling machine and levels, guarantees that the print medium is in print platform goes up to level and removes, is difficult for appearing the indentation.

Furthermore, the transverse supporting legs, the vertical supporting legs and the cross beams are all rectangular welded pipe fittings, the transverse supporting legs are fixedly connected with the vertical supporting legs in a penetrating mode, the vertical supporting legs are fixedly connected with the cross beams in a penetrating mode, a tongue-and-groove structure is formed, the bending resistance is good, and the structural strength is high.

Further, the back pendant is the arc section bar, the lower extreme of back pendant be equipped with a plurality of draw-in groove structures with the lower extreme assembly joint of back pendant backup pad guarantees the lower extreme of back pendant with the lower extreme relative activity of back pendant backup pad, then back pendant receives the extrusion alright elasticity adjustment from top to bottom because of propping paper when the paper feed to avoid warping, back pendant fixed plate with the section bar of notch cuttype is constituteed to back pendant backup pad, and structural strength is high, and easy installation and installation accuracy are high, can strengthen the structural stability of back pendant, the paper feed precision is high.

The paper feeding device has the advantages of scientific design, stable paper feeding, high structural strength of the frame, bending resistance and high paper feeding precision, and the tension roller is prevented from impacting a printing medium.

Drawings

Fig. 1 is a schematic structural view of the present invention.

Fig. 2 is a front view of the present invention.

Fig. 3 is a side view of the present invention.

Fig. 4 is a sectional view taken along line a-a in fig. 2.

Fig. 5 is a schematic structural view of the rear suspension member and the rear suspension member fixing assembly according to the present invention.

In the figure: 1. printing the body; 2. a wind-up roll; 3. a winding motor; 4. unwinding rollers; 5. an unwinding motor; 6. a front rotating roller; 7. a front crank; 8. a front tension roller; 9. a front limit catch post; 10. a first proximity switch; 11. a rear rotating roller; 12. a rear crank; 13. a rear tension roll; 14. a rear limit stop post; 15. a second proximity switch; 16. a power source; 17. a winding relay; 18. an unwinding relay; 19. a square steel body; 20. a printing platform; 21. a transverse leg; 22. vertical support legs; 23. a vertical plate; 24. a cross beam; 25. a gusset; 26. a caster wheel; 27. a roll stop; 28. a rear suspension member; 29. a rear suspension member fixing plate; 30. the rear suspension piece supports the reinforcing ribs; 31. the back pendant backup pad.

Detailed Description

The technical solution of the present invention is further described in detail by the following embodiments.

As shown in fig. 1-5, a photo machine with an electric control swing roller for stable paper feeding comprises a frame, a printing body 1, a winding roller 2, a winding motor 3, an unwinding roller 4 and an unwinding motor 5, wherein the printing body 1, the winding roller 2, the winding motor 3, the unwinding roller 4 and the unwinding motor 5 are respectively mounted on the frame, the winding motor 3 drives the winding roller 2 to rotate, the unwinding motor 5 drives the unwinding roller 4 to rotate, a front rotating roller 6 is rotatably mounted on the frame below the front of the printing body 1, front cranks 7 with the same angle direction are respectively mounted at two shaft ends of the front rotating roller 6, a front tension roller 8 is hinged between the two front cranks 7, the front tension roller 8 is parallel to the front rotating roller 6, two front limiting stop posts 9 for limiting the front-back swing amplitude of the front crank 7 are mounted on the frame of the front rotating roller, a matched first proximity switch 10 is arranged on the shaft end of the front rotating roller 6 and the rack at the shaft end; a rear rotating roller 11 which is symmetrical to the front rotating roller 6 is rotatably mounted on a frame below the rear of the printing body 1, rear cranks 12 with the same angle and direction are respectively mounted at two shaft ends of the rear rotating roller 11, a rear tension roller 13 is hinged between the two rear cranks 12, the rear tension roller 13 is arranged in parallel with the rear rotating roller 11, two rear limiting blocking columns 14 for limiting the front-rear swinging amplitude of the rear cranks 12 are mounted on a frame at the shaft end of the rear rotating roller, and a matched second proximity switch 15 is mounted on the shaft end of the rear rotating roller 11 and the frame at the shaft end; the rack is also provided with an electric cabinet, a power supply 16, a winding relay 17 and an unwinding relay 18 are arranged in the electric cabinet, and the power supply 16 is respectively and electrically connected with the winding motor 3, the unwinding motor 5, the first proximity switch 10 and the second proximity switch 15; the first proximity switch 10 is electrically connected with the winding relay 17, the winding relay 17 is electrically connected with the winding motor 3, when a probe of the first proximity switch 10 detects an approach signal, the winding relay 17 is triggered to control the winding motor 3 to start, the winding roller 2 rotates to wind, and when the probe of the first proximity switch 10 does not detect the approach signal, the winding relay 17 is triggered to control the winding motor 3 to close; the second proximity switch 15 is electrically connected with the unwinding relay 18, the unwinding relay 18 is electrically connected with the unwinding motor 5, when the probe of the second proximity switch 15 cannot detect a proximity signal, the unwinding relay 18 is triggered to control the unwinding motor 5 to be started, the unwinding roller 4 rotates to unwind, and when the probe of the second proximity switch 15 detects a proximity signal, the unwinding relay 18 is triggered to control the unwinding motor 5 to be turned off; each rolling of the winding roller 2 and each unwinding of the unwinding roller 4 are synchronous with each movement of the printing medium on the printing body 1, and the rolling length and the unwinding length are the same as the movement length.

Print body 1 including transversely putting two erect square steel main part 19 and print platform 20 on landing leg 22 top, a plurality of printing support section bars are installed to the up end of square steel main part 19, print platform 20 assembles in each upper end of printing support section bar, print platform 20 is integrated into one piece's aluminium alloy panel, the upper and lower surface of aluminium alloy panel mills through the milling machine and levels.

The frame comprises a horizontal leg 21 arranged at two sides of the printing body 1, a vertical leg 22 assembled with the horizontal leg 21, a vertical plate 23 and a cross beam 24 arranged on the outer side wall of the vertical leg 22, the transverse legs 21, the vertical legs 22 and the transverse beams 24 are all rectangular welded pipe fittings, the bottom of the vertical leg 22 vertically penetrates the middle part of the horizontal leg 21, an angle plate 25 is connected at the joint of the vertical leg 22 and the horizontal leg 21 to fix the vertical leg 22, two end parts of the cross beam 24 vertically penetrate through the middle parts of the vertical legs 22, corner plates 25 are connected at the joints of the cross beam 24 and the vertical legs 22 to fix the cross beam 24, the bottom edge of the vertical plate 23 presses on the upper plane of the horizontal leg 21, an angle plate 25 is connected to the joint of the vertical plate 23 and the horizontal leg 21 to fix the vertical plate 23, and casters 26 are mounted at two ends of the bottom plate of the horizontal leg 21.

The winding roller 2 is rotatably mounted on a lower front vertical plate 23 of the printing body 1, the unwinding roller 4 is rotatably mounted on a lower rear vertical plate 23 of the printing body 1, and two winding drum stoppers 27 are mounted on the winding roller 2 and the unwinding roller 4.

Print body 1 and still include the fixed subassembly of back pendant 28 and back pendant, back pendant 28 is integrated into one piece's arc section bar, the arc angle of back pendant 28 is less than 90, the fixed subassembly of back pendant is the fixed section bar of notch cuttype, the fixed subassembly assembly of back pendant is in on the square steel main part 19, back pendant 28 covers and installs on the fixed subassembly of back pendant.

The fixed subassembly of back pendant supports strengthening rib 30 and becomes the back pendant backup pad 31 of notch cuttype including the back pendant fixed plate 29, a plurality of back pendant of the L type, back pendant backup pad 31 includes the vertical board in inboard vertical board, middle horizontal board and the vertical board in the outside, the vertical board in inboard vertical board in middle horizontal board with the vertical board integrated into one piece in the outside is the ladder section bar, the vertical board lower extreme integrated into one piece in the outside has U type hem, the interior riser upper end integrated into one piece of back pendant fixed plate 29 has the right angle hem, back pendant fixed plate 29 with the vertical butt joint of the vertical board in inboard, each back pendant supports the perpendicular fixed connection of strengthening rib 30 equidistance back pendant support the lower terminal surface of back pendant fixed plate 29 with the medial surface of the vertical board in inboard.

Each back pendant supporting reinforcing rib 30 and each printing supporting section bar are arranged in a staggered and parallel mode, the lower end face of each back pendant supporting reinforcing rib 30 is fixedly installed on the upper end face of each back pendant supporting reinforcing rib 30, the inner side face of the inner side vertical plate is fixedly installed on the outer side face of each printing supporting section bar, the lower end face of the middle horizontal straight plate is in press connection with the upper surface of the square steel main body 19, the inner side face of the outer side vertical plate is in press connection with the outer side face of the square steel main body 19, the upper end of the back pendant 28 is installed on the right-angle folding edge of the back pendant fixing plate 29, the lower end of the back pendant 28 is provided with a plurality of clamping grooves with downward openings, the lower end of the back pendant 28 is assembled and clamped on the U-shaped folding edge of the outer side vertical plate through each clamping groove, the upper end of the back pendant 28 is integrally formed with a paper feeding, the edge of the paper feeding flat plate is butted at the front edge of the printing platform 20, and the paper feeding flat plate is flush with the upper surface of the printing platform 20.

The working principle and the advantages of the printer with the electric control swing roller for paper feeding stability of the invention are that the front tension roller 8 and the rear tension roller 13 respectively swing back and forth around the front rotating roller 6 and the rear rotating roller 11, a printing medium is moved out after spray printing is completed on the printing platform 20, and moves for a certain length once towards the winding roller 2, so that the front tension roller 8 presses the surface of the printing medium to swing forwards to prop up the printing medium, the printing medium is prevented from bending and wrinkling and the winding quality is prevented from being influenced, when the front tension roller 8 swings forwards until the front crank 7 props against the front limit stop post 9 at the front end of the front rotating roller 6, when a probe of the first proximity switch 10 detects a proximity signal, the winding relay 17 is triggered to control the winding motor 3 to start, the winding roller 2 rotates to wind the printed printing medium, when the probe of the first proximity switch 10 does not detect a proximity signal, triggering the winding relay 17 to control the winding motor 3 to be turned off; similarly, the paper feeding and paper discharging at the rear end of the printing platform 20 are synchronous, that is, when the printing medium finishes the spray printing with a certain length, the non-printed printing medium moves to the printing platform 20 with a certain length, the rear tension roller 13 swings forward under the driving of the printing medium to support the printing medium, so that the surface of the printing medium is flat when the printing medium enters the printing platform 20, meanwhile, the probe of the second proximity switch 15 cannot detect a proximity signal, the unwinding relay 18 is triggered to control the unwinding motor 5 to start, the unwinding roller 4 rotates to unwind, when the rear tension roller 13 swings forward until the orientation of the rear crank 12 is close to vertical upward, the probe of the second proximity switch 15 detects a proximity signal, triggers the unwinding relay 18 to control the unwinding motor 5 to be turned off, and meanwhile, the movement of the printing medium on the printing body 1 is finished; each winding of the winding roller 2 and each unwinding of the unwinding roller 4 are synchronous with each movement of the printing medium on the printing body 1, and the winding length and the unwinding length are the same as the movement length; therefore, the paper feeding stability can be ensured, the front tension roller 8 and the rear tension roller 13 support and level the printing medium through swinging, so that the printing medium is prevented from being impacted greatly and is not easy to damage;

the printing platform 20 is an integrally formed aluminum profile panel, the upper surface and the lower surface of the aluminum profile panel are milled and leveled by a milling machine, so that a printing medium is guaranteed to move flatly on the printing platform 20, and indentations are not easy to occur;

the transverse supporting legs 21, the vertical supporting legs 22 and the cross beams 24 are all rectangular welded pipe fittings, the transverse supporting legs 21 and the vertical supporting legs 22 are fixedly connected in a penetrating manner, the vertical supporting legs 22 and the cross beams 24 are fixedly connected in a penetrating manner, a tongue-and-groove structure is formed, the bending resistance is good, and the structural strength is high;

the back pendant 28 is the arc section bar, the last lower extreme of back pendant 28 is fixed connection respectively in the upper end of back pendant fixed plate 29 with the lower extreme of back pendant backup pad 31, back pendant fixed plate 29 with back pendant backup pad 31 is the section bar of taking the right angle, and structural strength is high, and easy installation and installation accuracy are high, strengthens the structural stability of back pendant 28 prevents back pendant 28 warp at the paper feed in-process, and the paper feed precision is high.

Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present invention and not to limit the same; although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art will understand that: modifications to the specific embodiments of the invention or equivalent substitutions for parts of the technical features may be made; without departing from the spirit of the present invention, it is intended to cover all aspects of the invention as defined by the appended claims.

Claims

1. The utility model provides a steady pictorial machine who takes automatically controlled balance roller of paper feed, includes the frame, prints body, wind-up roll, rolling motor, unreels the roller and unreels the motor, print body, wind-up roll, rolling motor, unreel the roller and unreel the motor and install respectively in the frame, the rolling motor drive the wind-up roll rotates, unreel motor drive the unreel the roller and rotate its characterized in that: a front rotating roller is rotatably arranged on a rack below the front of the printing body, front cranks with the same angle and direction are respectively arranged at two shaft ends of the front rotating roller, a front tension roller is hinged between the two front cranks and is arranged in parallel with the front rotating roller, two front limiting stop posts used for limiting the front and back swing amplitude of the front cranks are arranged on the rack at the shaft end of the front rotating roller, and matched first proximity switches are arranged on the shaft end of the front rotating roller and the rack at the shaft end; a rear rotating roller which is symmetrical to the front rotating roller is rotatably arranged on a rack below the rear part of the printing body, rear cranks with the same angle and direction are respectively arranged at two shaft ends of the rear rotating roller, a rear tension roller is hinged between the two rear cranks and is arranged in parallel with the rear rotating roller, two rear limiting stop posts for limiting the front-rear swinging amplitude of the rear cranks are arranged on a rack at the shaft end of the rear rotating roller, and matched second proximity switches are arranged on the shaft end of the rear rotating roller and the rack at the shaft end;

the rack is also provided with an electric cabinet, a power supply, a winding relay and an unwinding relay are arranged in the electric cabinet, and the power supply is respectively and electrically connected with the winding motor, the unwinding motor, the first proximity switch and the second proximity switch; the first proximity switch is electrically connected with the winding relay, the winding relay is electrically connected with the winding motor, when a probe of the first proximity switch detects an approach signal, the winding relay is triggered to control the winding motor to start, the winding roller rotates to wind, and when the probe of the first proximity switch does not detect the approach signal, the winding relay is triggered to control the winding motor to close; the second proximity switch is electrically connected with the unwinding relay, the unwinding relay is electrically connected with the unwinding motor, when a probe of the second proximity switch cannot detect an approaching signal, the unwinding relay is triggered to control the unwinding motor to be started, the unwinding roller rotates to unwind, and when the probe of the second proximity switch detects the approaching signal, the unwinding relay is triggered to control the unwinding motor to be turned off; each rolling of the rolling roller and each rolling of the rolling roller are synchronous with each movement of the printing medium on the printing body, and the rolling length are the same as the moving length;

the printing body comprises a rear pendant and a rear pendant fixing component, the rear pendant is an integrally formed arc-shaped section, an arc angle of the rear pendant is smaller than 90 degrees, the rear pendant fixing component is a stepped fixing section, and the rear pendant is covered and installed on the rear pendant fixing component;

the subassembly is fixed to back pendant includes back pendant fixed plate, a plurality of back pendant support strengthening rib and the back pendant backup pad of becoming the notch cuttype of L type, back pendant backup pad includes the vertical board in inboard vertical board, middle horizontal straight board and the vertical board in the outside, the vertical board in inboard vertical board in middle horizontal straight board with the vertical board integrated into one piece in the outside is the ladder section bar, the vertical board lower extreme integrated into one piece in the outside has U type hem, the interior riser upper end integrated into one piece of back pendant fixed plate has the right angle hem, back pendant fixed plate with the vertical butt joint of the vertical board in inboard, each back pendant supports the perpendicular fixed connection of strengthening rib equidistance the lower terminal surface of back pendant fixed plate with the medial surface of the vertical board in inboard.

2. The printer of claim 1, wherein the printer is characterized in that: the printing body is still including transversely installing square steel main part and print platform in the frame, a plurality of printing support section bars are installed to the up end of square steel main part, print platform assembles in the upper end that each prints the support section bar, print platform is integrated into one piece's aluminium alloy panel, the upper and lower surface of aluminium alloy panel mills through the milling machine and makes level and smooth, the fixed subassembly assembly of back pendant is in the square steel main part.

3. The printer of claim 2, wherein the printer is characterized in that: the printing machine comprises a rack, a printing body, a printing head, a machine frame and a printing head, wherein the rack comprises transverse support legs arranged on two sides of the printing body, vertical support legs assembled with the transverse support legs, a vertical plate and a cross beam, the vertical plate and the cross beam are installed on the outer side walls of the vertical support legs, the transverse support legs, the vertical support legs and the cross beam are all rectangular welded pipe fittings, the bottoms of the vertical support legs are vertically connected in the middle of the transverse support legs in a penetrating manner, corner plates are connected at the joints of the vertical support legs and the vertical support legs to fix the vertical support legs, corner plates are connected at the joints of the vertical plate and the vertical support legs to fix the cross beam, the bottom edges of the vertical plate are pressed on the upper planes of the transverse support legs, corner plates are connected at the joints of the vertical plate; the square steel main body is arranged at the top ends of the two vertical supporting legs.

4. The printer of claim 3, wherein the printer is characterized in that: the winding roller is rotatably installed on a vertical plate below the front portion of the printing body, the unwinding roller is rotatably installed on a vertical plate below the rear portion of the printing body, and two winding drum blocking pieces are installed on the winding roller and the unwinding roller.

5. The printer of claim 4, wherein the printer is characterized in that: each back pendant supports strengthening rib and each prints support profile dislocation parallel arrangement, the lower terminal surface fixed mounting of back pendant fixed plate is at the up end of each back pendant support strengthening rib, the medial surface fixed mounting of inboard vertical board is on the lateral surface of each printing support profile, the lower terminal surface crimping of middle horizontal straight board is in the upper surface of square steel main part, the medial surface crimping of outside vertical board is in the lateral surface of square steel main part, the upper end of back pendant is installed on the right angle hem of back pendant fixed plate, the lower extreme of back pendant is equipped with a plurality of draw-in grooves of downward opening, the lower extreme of back pendant passes through each draw-in groove assembly joint in the U type hem of outside vertical board, the upper end integrated into one piece of back pendant has the paper feed flat board, the equidistant a plurality of rectangular paper feed wheel mounting holes that are equipped with of paper feed flat board, the border butt joint of paper feed flat board is in the preceding border of printing platform, the paper feeding flat plate is flush with the upper surface of the printing platform.