CN214164390U

CN214164390U - Switching device of double-sided printing flexographic rotary printing machine

Info

Publication number: CN214164390U
Application number: CN202022911633.1U
Authority: CN
Inventors: 肖成兵; 陈飞跃; 张振豪
Original assignee: Guangzhou Penghua Poker Co ltd
Current assignee: Guangzhou Penghua Poker Co ltd
Priority date: 2020-12-07
Filing date: 2020-12-07
Publication date: 2021-09-10
Anticipated expiration: 2030-12-07

Abstract

A switching device of a double-sided printing flexographic rotary printing machine comprises a box body, a printing stock, a printing assembly, a second supporting plate, a first rotating shaft, a second rotating shaft and an induction assembly; six groups of guide roller sets are arranged in the box body; the printing stock passes through six groups of guide roller sets in sequence; the sliding plate is arranged on the inner wall of the rear side of the box body, and a power device is arranged on the sliding plate; the first supporting plate is arranged on the sliding plate; the first spring is arranged on the first supporting plate; the first rotating shaft is rotatably connected with the box wall at the rear side of the box body, and the end part of the first rotating shaft is provided with a special-shaped cam; the second rotating shaft is rotatably connected with the box wall at the rear side of the box body, and a cam is arranged at the end part of the second rotating shaft; the fifth supporting plate is arranged on the inner wall of the rear side of the box body, and a pressure sensor is arranged on the fifth supporting plate; the moving plate is horizontally arranged on the sliding plate. The utility model discloses in, just can switch the printing state through rotating first axis of rotation and second axis of rotation, select to carry out single face printing still two-sided printing, printing state switches labour saving and time saving, easy operation.

Description

Switching device of double-sided printing flexographic rotary printing machine

Technical Field

The utility model relates to a lithography apparatus technical field especially relates to a two-sided printing flexographic rotary press auto-change over device.

Background

Flexography is a printing method that uses a flexographic plate to apply ink by passing it through an anilox roller. Flexography can only be usually carried out single-sided printing, the printing efficiency is lower, and double-sided printing generally needs to turn over the printing coiled material to the other side to continue printing of the second side after one side is printed, so that the turning process is long in time consumption, and is not beneficial to improving the printing production efficiency.

SUMMERY OF THE UTILITY MODEL

Objects of the invention

For solving the technical problem who exists among the background art, the utility model provides a two-sided printing flexographic rotary press auto-change over device just can switch the printing state through rotating first axis of rotation and second axis of rotation, selects to carry out single face printing still two-sided printing, and can also select to use first printing component still second printing component when the single face printing, and the printing state switches labour saving and time saving, easy operation.

(II) technical scheme

The utility model provides a switching device of a double-sided printing flexible plate rotary printing machine, which comprises a box body, a printing stock, a printing assembly, a second support plate, a first rotating shaft, a second rotating shaft and an induction assembly; the printing assembly comprises a sliding plate, an impression cylinder, a printing unit, a first supporting plate and a first spring; the induction assembly comprises a fifth supporting plate and a moving plate;

the box body is internally provided with six groups of horizontal guide roller sets, each group of guide roller sets comprises two groups of rotating rollers which are parallel to each other, the six groups of guide roller sets are distributed in three rows and two columns, and the left end and the right end of the box body are provided with through holes for printing stocks to pass through; the printing stock penetrates through the through hole at the left end of the box body and extends into the box body, the printing stock penetrates through the first row of guide roller sets from left to right, then penetrates through the second row of guide roller sets from right to left, then penetrates through the third row of guide roller sets from left to right, and finally penetrates out of the through hole at the right end of the box body;

the sliding plate is arranged on the inner wall of the rear side of the box body in a sliding manner, the sliding direction is the up-down direction, the sliding plate is positioned between a printing stock and the inner wall of the rear side of the box body, and a power device for driving the imprinting roller to rotate is arranged on the end face, facing the front of the box body, of the sliding plate; the impression cylinder is parallel to the guide roller group and is positioned between the first row of guide roller group and the second row of guide roller group; the printing unit is positioned above the first row of guide roller sets and is parallel to the impression cylinder; the first supporting plate is horizontally arranged on the end face, facing the box wall on the left side of the box body, of the sliding plate; the first spring is vertically arranged on the end face, facing the second support plate, of the first support plate, the end part of the first spring is connected with the second support plate, and the first spring is in a stretching state; the printing assemblies are arranged into two groups and comprise a first printing assembly positioned above the second row of guide roller sets and a second printing assembly positioned below the second row of guide roller sets, the impression cylinder of the second printing assembly is positioned between the second row of guide roller sets and the third row of guide roller sets, and the printing unit in the second printing assembly is positioned below the third row of guide roller sets; the first rotating shaft penetrates through the box body rear side box wall and is in rotating connection with the box body rear side box wall, the first rotating shaft is parallel to the guide roller set, the first rotating shaft is located between the two groups of sliding plates, a special-shaped cam is arranged at the end part of the first rotating shaft located in the box body, and the special-shaped cam is provided with two convex parts which are horizontally symmetrical relative to the first rotating shaft; a first rotating assembly which drives the first rotating shaft to rotate ninety degrees clockwise is arranged on the outer wall of the rear side of the box body; the second rotating shaft penetrates through the box body rear side box wall and is connected with the box body rear side box wall in a rotating mode, the second rotating shaft is parallel to the guide roller set, the second rotating shaft is located between the two groups of sliding plates, a cam is arranged at the end portion, located in the box body, of the second rotating shaft, the protruding portion of the cam faces the box body left side box wall, the cam is located between the special-shaped cam and the box body rear side inner wall, and a second rotating assembly for driving the second rotating shaft to rotate ninety degrees clockwise or anticlockwise is arranged on the box body rear side outer wall; a positioning component for fixing the positions of the first rotating component and the second rotating component is arranged on the inner wall of the rear side of the box body; the fifth supporting plate is horizontally arranged on the inner wall of the rear side of the box body, and a pressure sensor is arranged on the end face, facing the moving plate, of the fifth supporting plate; the moving plate is horizontally arranged on the sliding plate, and when the sliding plate is positioned at the top, the moving plate is contacted with the pressure sensor; the two groups of sensing assemblies are arranged and correspond to the two groups of printing assemblies one by one; the device is provided with a control system, the control system is in control connection with the power device, and the control system is in signal transmission connection with the pressure sensor.

Preferably, the first rotating assembly comprises a first rotating plate and a first limiting rod; the first rotating plate is horizontally arranged on the end part of the first rotating shaft, which is positioned at the rear part of the box body; a first arc-shaped groove is formed in the outer wall of the rear side of the box body, the arc center of the first arc-shaped groove is located on the axis of the first rotating shaft, and the arc center angle of the first arc-shaped groove is ninety degrees; the first limiting rod is vertically arranged on the end face, facing the box body, of the first rotating plate, and the end portion of the first limiting rod is inserted into the first arc-shaped groove in a matched mode.

Preferably, the second rotating assembly comprises a second rotating plate and a second limiting rod; the second rotating plate is horizontally arranged on the end part of the second rotating shaft, which is positioned at the rear part of the box body; a second arc-shaped groove is formed in the outer wall of the rear side of the box body, the arc center of the second arc-shaped groove is located on the axis of the second rotating shaft, and the arc center angle of the second arc-shaped groove is one hundred eighty degrees; the second limiting rod is vertically arranged on the end face, facing the box body, of the second rotating plate, and the end portion of the second limiting rod is inserted into the second arc-shaped groove in a matched mode.

Preferably, the positioning assembly comprises a third support plate, a second spring, a fourth support plate and a guide block; the third supporting plate is horizontally arranged on the outer wall of the rear side of the box body; the second spring is vertically arranged on the third support plate, and the end part of the second spring is connected with the fourth support plate; the fourth supporting plate is arranged on the outer wall of the rear side of the box body in a sliding mode, and the sliding direction is the up-down direction; the guide block is arranged on the end face, facing the first arc-shaped groove, of the fourth support plate, the vertical section of the guide block is in the shape of a quarter circle, the circumference of the guide block faces the first limiting rod, and the first limiting rod is located between the guide block and the wall of the first arc-shaped groove when the first rotating plate rotates clockwise by ninety degrees; the positioning assemblies are arranged in three groups, and the three groups of positioning assemblies are respectively positioned above the first arc-shaped groove, above the second arc-shaped groove and below the second arc-shaped groove.

Preferably, the bottom of the box body is provided with a plurality of groups of universal wheels.

Preferably, two groups of drying mechanisms are arranged in the box body, one group of drying mechanisms is located above the first row of guide roller sets, the drying mechanisms are located in front of the printing units in the first printing assembly in the moving direction of the printing stock, the other group of drying mechanisms is located below the third row of guide roller sets, and the drying mechanisms are located in front of the printing units in the second printing assembly in the moving direction of the printing stock.

The above technical scheme of the utility model has following profitable technological effect: open box body front side lid, pass the stock in proper order and close the lid behind the multiunit guide roller group, if need single face printing, rotate the second axis of rotation through second rotating assembly ninety degrees can, if clockwise rotation then second printing component prints, if anticlockwise rotation then first printing component prints, if need two-sided printing, through first rotating assembly with first axis of rotation clockwise ninety degrees, the two sets of slides of dysmorphism cam promotion are kept away from each other, first printing component and second printing component print the stock two sides simultaneously, just can switch the printing state through rotating first axis of rotation and second axis of rotation, choose to carry out single face printing or two-sided printing, and can also select to use first printing component or second printing component when single face printing, the printing state switches labour saving and time saving, and easy operation.

Drawings

Fig. 1 is a schematic structural diagram of a switching device of a double-sided printing flexographic rotary printing machine according to the present invention.

Fig. 2 is a rear view of the switching device of the double-sided printing flexographic rotary printing machine according to the present invention.

Reference numerals: 1. a box body; 2. a guide roller set; 3. a via hole; 4. a substrate; 5. a slide plate; 6. a power plant; 7. an impression cylinder; 8. a printing unit; 9. a first support plate; 10. a first spring; 11. a second support plate; 12. a first rotating shaft; 13. a shaped cam; 14. a first rotating plate; 15. a first limit rod; 16. a first arc-shaped slot; 17. a second rotating shaft; 18. a cam; 19. a second rotating plate; 20. a second limiting rod; 21. a second arc-shaped slot; 22. a fifth support plate; 23. a pressure sensor; 24. a third support plate; 25. a second spring; 26. a fourth support plate; 27. a guide block; 28. a drying mechanism; 29. and (5) moving the plate.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in detail with reference to the accompanying drawings. It should be understood that the description is intended to be illustrative only and is not intended to limit the scope of the present invention. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present invention.

As shown in fig. 1-2, the switching device of a double-sided printing flexographic plate rotary press according to the present invention comprises a box body 1, a printing material 4, a printing assembly, a second supporting plate 11, a first rotating shaft 12, a second rotating shaft 17 and an induction assembly; the printing assembly comprises a sliding plate 5, an impression cylinder 7, a printing unit 8, a first supporting plate 9 and a first spring 10; the induction assembly comprises a fifth support plate 22 and a moving plate 29;

the front side of the box body 1 is provided with a box cover, six groups of horizontal guide roller sets 2 are arranged in the box body 1, each group of guide roller sets 2 comprises two groups of rotating rollers which are parallel to each other, the six groups of guide roller sets 2 are distributed in three rows and two columns, and the left end and the right end of the box body 1 are provided with through holes 3 for printing stocks 4 to pass through; the printing stock 4 penetrates through the through hole 3 at the left end of the box body 1 and extends into the box body 1, the printing stock 4 penetrates through the first row of guide roller sets 2 from left to right, then penetrates through the second row of guide roller sets 2 from right to left, then penetrates through the third row of guide roller sets 2 from left to right, and finally penetrates out of the through hole 3 at the right end of the box body 1;

the sliding plate 5 is arranged on the inner wall of the rear side of the box body 1 in a sliding way, the sliding direction is the up-down direction, the sliding plate 5 is positioned between the printing stock 4 and the inner wall of the rear side of the box body 1, and the end surface of the sliding plate 5 facing the front side of the box body 1 is provided with a power device 6 for driving the impression cylinder 7 to rotate; the impression cylinder 7 is parallel to the guide roller group 2, and the impression cylinder 7 is positioned between the first row of guide roller group 2 and the second row of guide roller group 2; the printing unit 8 is positioned above the first row of guide roller groups 2, and the printing unit 8 is parallel to the impression cylinder 7; the first supporting plate 9 is horizontally arranged on the end surface of the sliding plate 5 facing to the left box wall of the box body 1; the first spring 10 is vertically arranged on the end face, facing the second support plate 11, of the first support plate 9, the end part of the first spring 10 is connected with the second support plate 11, and the first spring 10 is in a stretching state; the printing assemblies are arranged into two groups, and each group comprises a first printing assembly positioned above the second row of guide roller sets 2 and a second printing assembly positioned below the second row of guide roller sets 2, an impression cylinder 7 of each second printing assembly is positioned between the second row of guide roller sets 2 and the third row of guide roller sets 2, and a printing unit 8 in each second printing assembly is positioned below the third row of guide roller sets 2; the first rotating shaft 12 penetrates through the box wall at the rear side of the box body 1, the first rotating shaft 12 is rotatably connected with the box wall at the rear side of the box body 1, the first rotating shaft 12 is parallel to the guide roller set 2, the first rotating shaft 12 is positioned between the two groups of sliding plates 5, the end part of the first rotating shaft 12, which is positioned in the box body 1, is provided with a special-shaped cam 13, and the special-shaped cam 13 has two convex parts which are horizontally symmetrical with respect to the first rotating shaft 12; a first rotating assembly which drives the first rotating shaft 12 to rotate ninety degrees clockwise is arranged on the outer wall of the rear side of the box body 1; a second rotating shaft 17 penetrates through the box wall at the rear side of the box body 1, the second rotating shaft 17 is rotatably connected with the box wall at the rear side of the box body 1, the second rotating shaft 17 is parallel to the guide roller set 2, the second rotating shaft 17 is positioned between the two groups of sliding plates 5, a cam 18 is arranged at the end part of the second rotating shaft 17 positioned in the box body 1, the convex part of the cam 18 faces the box wall at the left side of the box body 1, the cam 18 is positioned between the special-shaped cam 13 and the inner wall at the rear side of the box body 1, and a second rotating assembly for driving the second rotating shaft 17 to rotate ninety degrees clockwise or anticlockwise is arranged on; a positioning component for fixing the positions of the first rotating component and the second rotating component is arranged on the inner wall of the rear side of the box body 1; a fifth supporting plate 22 is horizontally arranged on the inner wall of the rear side of the box body 1, and a pressure sensor 23 is arranged on the end face, facing the moving plate 29, of the fifth supporting plate 22; the moving plate 29 is horizontally arranged on the sliding plate 5, and when the sliding plate 5 is positioned at the top, the moving plate 29 is contacted with the pressure sensor 23; the two groups of sensing assemblies are arranged and correspond to the two groups of printing assemblies one by one; the device is provided with a control system, the control system is in control connection with the power device 6, and the control system is in signal transmission connection with the pressure sensor 23.

The utility model discloses in, open 1 front side lid of box body, close the lid after passing multiunit guide roller set 2 with stock 4 in proper order, if need single face printing, through second rotating assembly with second axis of rotation 17 rotate ninety degrees can, if clockwise rotation then second printing component prints, if anticlockwise rotation then first printing component prints, if need two-sided printing, through first rotating assembly with 12 clockwise rotations ninety degrees of first axis of rotation, special-shaped cam 13 promotes two sets of slides 5 and keeps away from each other, first printing component and second printing component print stock 4 two sides simultaneously. The utility model discloses in, just can switch the printing state through rotating first axis of rotation 12 and second axis of rotation 17, select to carry out single face printing or two-sided printing, and can also select to use first printing module or second printing module when single face printing, printing state switches labour saving and time saving, easy operation.

In an alternative embodiment, the first rotation assembly includes a first rotation plate 14 and a first limit lever 15; the first rotation plate 14 is horizontally provided on an end portion of the first rotation shaft 12 located at the rear of the case 1; a first arc-shaped groove 16 is formed in the outer wall of the rear side of the box body 1, the arc center of the first arc-shaped groove 16 is located on the axis of the first rotating shaft 12, and the arc center angle of the first arc-shaped groove 16 is ninety degrees; the first limiting rod 15 is vertically arranged on the end face, facing the box body 1, of the first rotating plate 14, and the end part of the first limiting rod 15 is inserted into the first arc-shaped groove 16 in a matched mode; the first rotating shaft 12 is rotated by rotating the first rotating plate 14.

In an alternative embodiment, the second rotation assembly comprises a second rotation plate 19 and a second limit lever 20; the second rotating plate 19 is horizontally arranged on the end part of the second rotating shaft 17 at the rear part of the box body 1; a second arc-shaped groove 21 is formed in the outer wall of the rear side of the box body 1, the arc center of the second arc-shaped groove 21 falls on the axis of the second rotating shaft 17, and the arc center angle of the second arc-shaped groove 21 is one hundred eighty degrees; the second limiting rod 20 is vertically arranged on the end face, facing the box body 1, of the second rotating plate 19, and the end part of the second limiting rod 20 is inserted into the second arc-shaped groove 21 in a matched mode; the second rotating plate 19 is rotated to drive the second rotating shaft 17 to rotate.

In an alternative embodiment, the positioning assembly comprises a third support plate 24, a second spring 25, a fourth support plate 26 and a guide block 27; the third supporting plate 24 is horizontally arranged on the outer wall of the rear side of the box body 1; the second spring 25 is vertically arranged on the third support plate 24, and the end part of the second spring 25 is connected with the fourth support plate 26; the fourth supporting plate 26 is arranged on the outer wall of the rear side of the box body 1 in a sliding mode, and the sliding direction is the up-down direction; the guide block 27 is arranged on the end face, facing the first arc-shaped groove 16, of the fourth supporting plate 26, the vertical section of the guide block 27 is in a shape of a quarter circle, the circumference of the guide block is facing the first limiting rod 15, and the first limiting rod 15 is positioned between the guide block 27 and the groove wall of the first arc-shaped groove 16 when the first rotating plate 14 rotates clockwise by ninety degrees; the three groups of positioning assemblies are respectively positioned above the first arc-shaped groove 16, above the second arc-shaped groove 21 and below the second arc-shaped groove 21; after the first rotating plate 14 or the second rotating plate 19 rotates ninety degrees, the guide block 27 blocks the first limiting rod 15 or the second limiting rod 20, so that the first limiting rod 15 or the second limiting rod 20 cannot move reversely, the first rotating shaft 12 or the second rotating shaft 17 is fixed, the first rotating shaft 12 or the second rotating shaft 17 cannot rotate automatically, and stability in a printing process is guaranteed.

In an optional embodiment, a plurality of groups of universal wheels are arranged at the bottom of the box body 1; the device is convenient to move.

In an alternative embodiment, two sets of drying mechanisms 28 are arranged in the box body 1, wherein one set of drying mechanisms 28 is positioned above the first row of guide roller sets 2, in the moving direction of the printing materials 4, the drying mechanism 28 is positioned in front of the printing units 8 in the first printing assembly, the other set of drying mechanisms 28 is positioned below the third row of guide roller sets 2, and in the moving direction of the printing materials 4, the drying mechanism 28 is positioned in front of the printing units 8 in the second printing assembly; and the printed surface is dried in time, so that the printing effect is improved.

It is to be understood that the above-described embodiments of the present invention are merely illustrative of or explaining the principles of the invention and are not to be construed as limiting the invention. Therefore, any modification, equivalent replacement, improvement and the like made without departing from the spirit and scope of the present invention should be included in the protection scope of the present invention. Further, it is intended that the appended claims cover all such variations and modifications as fall within the scope and boundaries of the appended claims or the equivalents of such scope and boundaries.

Claims

1. A switching device of a double-sided printing flexographic rotary printing machine is characterized by comprising a box body (1), a printing stock (4), a printing assembly, a second supporting plate (11), a first rotating shaft (12), a second rotating shaft (17) and an induction assembly; the printing assembly comprises a sliding plate (5), an impression cylinder (7), a printing unit (8), a first supporting plate (9) and a first spring (10); the induction assembly comprises a fifth support plate (22) and a moving plate (29);

the box cover is arranged on the front side of the box body (1), six groups of horizontal guide roller sets (2) are arranged in the box body (1), each group of guide roller sets (2) comprises two groups of rotating rollers which are parallel to each other, the six groups of guide roller sets (2) are distributed in three rows and two columns, and through holes (3) for printing stocks (4) to pass through are formed in the left end and the right end of the box body (1); the printing stock (4) penetrates through the through hole (3) at the left end of the box body (1) and extends into the box body (1), the printing stock (4) penetrates through the first row of guide roller sets (2) from left to right, then penetrates through the second row of guide roller sets (2) from right to left and then penetrates through the third row of guide roller sets (2) from left to right, and the printing stock (4) finally penetrates out of the through hole (3) at the right end of the box body (1);

the sliding plate (5) is arranged on the inner wall of the rear side of the box body (1) in a sliding mode, the sliding direction is the up-down direction, the sliding plate (5) is located between the printing stock (4) and the inner wall of the rear side of the box body (1), and a power device (6) for driving the impression cylinder (7) to rotate is arranged on the end face, facing the front side of the box body (1), of the sliding plate (5); the impression cylinder (7) is parallel to the guide roller group (2), and the impression cylinder (7) is positioned between the first row of guide roller group (2) and the second row of guide roller group (2); the printing unit (8) is positioned above the first row of guide roller sets (2), and the printing unit (8) is parallel to the impression cylinder (7); the first supporting plate (9) is horizontally arranged on the end face, facing the left box wall, of the box body (1), of the sliding plate (5); the first spring (10) is vertically arranged on the end face, facing the second supporting plate (11), of the first supporting plate (9), the end part of the first spring (10) is connected with the second supporting plate (11), and the first spring (10) is in a stretching state; the printing assemblies are arranged into two groups and comprise a first printing assembly positioned above the second row of guide roller sets (2) and a second printing assembly positioned below the second row of guide roller sets (2), the impression cylinder (7) of the second printing assembly is positioned between the second row of guide roller sets (2) and the third row of guide roller sets (2), and the printing unit (8) in the second printing assembly is positioned below the third row of guide roller sets (2); the first rotating shaft (12) penetrates through the box wall on the rear side of the box body (1), the first rotating shaft (12) is rotatably connected with the box wall on the rear side of the box body (1), the first rotating shaft (12) is parallel to the guide roller set (2), the first rotating shaft (12) is located between the two groups of sliding plates (5), the end part, located in the box body (1), of the first rotating shaft (12) is provided with a special-shaped cam (13), the special-shaped cam (13) has two protruding parts, and the two protruding parts are horizontally symmetrical about the first rotating shaft (12); a first rotating assembly which drives the first rotating shaft (12) to rotate ninety degrees clockwise is arranged on the outer wall of the rear side of the box body (1); the second rotating shaft (17) penetrates through the box wall on the rear side of the box body (1), the second rotating shaft (17) is rotatably connected with the box wall on the rear side of the box body (1), the second rotating shaft (17) is parallel to the guide roller set (2), the second rotating shaft (17) is positioned between the two groups of sliding plates (5), a cam (18) is arranged at the end part of the second rotating shaft (17) positioned in the box body (1), the protruding part of the cam (18) faces the box wall on the left side of the box body (1), the cam (18) is positioned between the special-shaped cam (13) and the inner wall on the rear side of the box body (1), and a second rotating assembly for driving the second rotating shaft (17) to rotate ninety degrees clockwise or anticlockwise is arranged on the outer wall on the rear side of the box body (1); a positioning component for fixing the positions of the first rotating component and the second rotating component is arranged on the inner wall of the rear side of the box body (1); the fifth supporting plate (22) is horizontally arranged on the inner wall of the rear side of the box body (1), and a pressure sensor (23) is arranged on the end face, facing the moving plate (29), of the fifth supporting plate (22); the moving plate (29) is horizontally arranged on the sliding plate (5), and when the sliding plate (5) is positioned at the top, the moving plate (29) is contacted with the pressure sensor (23); the two groups of sensing assemblies are arranged and correspond to the two groups of printing assemblies one by one; the device is provided with a control system, the control system is in control connection with the power device (6), and the control system is in signal transmission connection with the pressure sensor (23).

2. The changeover device of a double-sided printing flexographic printing machine according to claim 1, characterized in that the first rotary assembly comprises a first rotary plate (14) and a first limit lever (15); the first rotating plate (14) is horizontally arranged on the end part of the first rotating shaft (12) positioned at the rear part of the box body (1); a first arc-shaped groove (16) is formed in the outer wall of the rear side of the box body (1), the arc center of the first arc-shaped groove (16) is located on the axis of the first rotating shaft (12), and the arc center angle of the first arc-shaped groove (16) is ninety degrees; the first limiting rod (15) is vertically arranged on the end face, facing the box body (1), of the first rotating plate (14), and the end portion of the first limiting rod (15) is inserted into the first arc-shaped groove (16) in a matched mode.

3. The changeover device of a perfecting flexographic printing press according to claim 1, characterized in that the second rotary assembly comprises a second rotating plate (19) and a second limit lever (20); the second rotating plate (19) is horizontally arranged on the end part of the second rotating shaft (17) positioned at the rear part of the box body (1); a second arc-shaped groove (21) is formed in the outer wall of the rear side of the box body (1), the arc center of the second arc-shaped groove (21) is located on the axis of the second rotating shaft (17), and the arc center angle of the second arc-shaped groove (21) is one hundred eighty degrees; the second limiting rod (20) is vertically arranged on the end face, facing the box body (1), of the second rotating plate (19), and the end portion of the second limiting rod (20) is inserted into the second arc-shaped groove (21) in a matched mode.

4. The double-sided printing flexographic printing press switching device according to claim 1, characterized in that the positioning assembly comprises a third support plate (24), a second spring (25), a fourth support plate (26) and a guide block (27); the third supporting plate (24) is horizontally arranged on the outer wall of the rear side of the box body (1); the second spring (25) is vertically arranged on the third support plate (24), and the end part of the second spring (25) is connected with the fourth support plate (26); the fourth supporting plate (26) is arranged on the outer wall of the rear side of the box body (1) in a sliding mode, and the sliding direction is the vertical direction; the guide block (27) is arranged on the end face, facing the first arc-shaped groove (16), of the fourth support plate (26), the vertical section of the guide block (27) is in the shape of a quarter circle, the circumference of the guide block faces the first limiting rod (15), and the first limiting rod (15) is located between the guide block (27) and the groove wall of the first arc-shaped groove (16) when the first rotating plate (14) rotates clockwise by ninety degrees; the positioning assemblies are arranged in three groups, and the three groups of positioning assemblies are respectively positioned above the first arc-shaped groove (16), above the second arc-shaped groove (21) and below the second arc-shaped groove (21).

5. The changeover device of a perfecting flexographic printing machine according to claim 1, characterized in that the bottom of the box (1) is provided with sets of universal wheels.

6. The changeover device of a perfecting flexographic printing machine according to claim 1, characterized in that two sets of drying means (28) are provided in the box (1), one set of drying means (28) being located above the first set of guide rollers (2), the drying means (28) being located in front of the printing units (8) in the first printing group in the direction of movement of the substrate (4), the other set of drying means (28) being located below the third set of guide rollers (2), the drying means (28) being located in front of the printing units (8) in the second printing group in the direction of movement of the substrate (4).