Printing device for medical packaging plastic film
By combining tension guidance and anti-deviation mechanism, the tension of plastic film is monitored and adjusted in real time to prevent deviation. This solves the problem of damage and misalignment caused by excessive tension or deviation during the printing process of plastic packaging film, thereby improving printing quality and film lifespan.
Patent Information
- Application Number
- CN202511479415.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-16
- Publication Date
- 2026-01-02
AI Technical Summary
Existing plastic packaging film printing equipment is prone to film damage and printing information misalignment during the tensioning process, and lacks an effective anti-deviation structure.
Employing a tension guiding mechanism and an anti-deviation mechanism, the system monitors changes in winding thickness using a distance sensor, controls motor speed, and combines components such as contact rollers, clamping rollers, and vacuum pumps to achieve tension adjustment, physical positioning, and negative pressure adsorption of the plastic film, preventing deviation.
It effectively prevents damage to the plastic film due to excessive tension or misalignment, improves printing quality and service life, and ensures accurate drug information.
Smart Images
Figure CN121247545A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of packaging film printing technology, specifically to a printing apparatus for pharmaceutical packaging plastic films. Background Technology
[0002] In the pharmaceutical packaging industry, plastic packaging film, as the packaging material that comes into direct contact with medicines, is crucial. Its printing quality not only affects the clarity of drug information labeling but also relates to safety indicators such as airtightness and sterility during drug storage. Most of the unwinding and tensioning devices for printing plastic packaging films on the market currently rely on the rewinding shaft built into the printing equipment. This can easily cause damage to the plastic packaging film when the tension is too high, and it can also cause misalignment at the printing station, resulting in misprinting of key information such as drug batch numbers and anti-counterfeiting labels. Therefore, we propose a printing device for pharmaceutical packaging plastic films. Summary of the Invention
[0003] To solve the above-mentioned technical problems, this application provides a printing device for pharmaceutical packaging plastic film, including a support, and a feeding roller and a winding roller arranged on the support and facing each other. The support is also provided with a tension guiding mechanism, a printing mechanism is also provided on the top of the support, and an anti-deviation mechanism is also provided on the support.
[0004] In some embodiments, the tension guiding mechanism includes a fixed plate disposed opposite to the support, a guide roller group symmetrically disposed inside the fixed plate, a movable block disposed on both sides of the guide roller group, a limit frame sleeved and slidably installed on the outer wall of the movable block, and the limit frame disposed on the fixed plate, and the inner wall of the fixed plate is also provided with uniformly distributed protrusions, and a plurality of first spring rods are disposed on the ground of the protrusions, and the first spring rods are inserted into the movable blocks and slidably installed.
[0005] In some embodiments, a motor is provided on one side of the take-up roller, a synchronization plate is slidably mounted on one side of the take-up roller, a movable top plate is provided on one side of the synchronization plate, and a distance sensor is provided on the top surface of the take-up roller.
[0006] In some embodiments, a movable frame is sleeved and slidably mounted on the outer wall of the protrusion, and the movable frames are connected to each other by a connecting frame, which is connected to one end of the synchronization plate.
[0007] In some embodiments, one end of the movable frame and one end of the second reduction gear set are both provided with toothed plates, the bracket is provided with the second reduction gear set, and the second reduction gear set meshes with the connecting frame and the synchronizing plate respectively through the toothed plates.
[0008] In some embodiments, the anti-deviation mechanism includes a contact roller disposed on a fixed plate, and a plurality of clamping rollers are disposed on one side of the contact roller.
[0009] In some embodiments, an air extraction cylinder is inserted into the contact roller, and the air extraction cylinder is connected to a negative pressure mechanism through an air pipe. A negative pressure port is opened on the air extraction cylinder, and two rows of adsorption holes facing each other are opened on one side of the outer wall of the contact roller.
[0010] In some embodiments, an isolation plate is provided between the contact roller and the suction cylinder. A second spring rod is inserted into and slidably installed in the contact roller. A contact block is provided at the top of the second spring rod. A switching plate is provided at the bottom of the second spring rod. An insert plate is symmetrically provided on the bottom surface of the switching plate. The insert plate is inserted into the isolation plate and slidably assembled. The insert plate has evenly distributed air holes. A first sealing plate is provided on both sides of the negative pressure port. The insert plate and the first sealing plate are slidably assembled. A partition is provided between the contact roller and the suction cylinder. The partition is located between two rows of opposite suction holes. A cam is rotatably installed on one side of the contact roller. A pulley assembly is provided between the cam and the take-up roller. A second sealing plate is provided on the top surface of the isolation plate. The switching plate and the second sealing plate are slidably assembled.
[0011] In some embodiments, the top surface of the contact roller is further provided with two rows of pressure relief holes that are opposite to each other, and the two rows of pressure relief holes are located on both sides of the second spring rod.
[0012] In some embodiments, a first reduction gear set is provided between the take-up roller and the pulley assembly.
[0013] This invention has at least the following beneficial effects: The distance sensor monitors the thickness change of the take-up roll in real time. When the thickness reaches the preset threshold, it sends a signal to the control system. The control system controls the motor to decelerate and reduce the winding speed to avoid the roll tension being too tight. As the take-up roll continuously winds up the plastic film, the movable top plate moves upward under the push of the take-up roll. Through the meshing transmission of the synchronous plate and the second reduction gear set, it drives the connecting frame and the movable frame to move upward, releasing the activity space for the guide roller group. If the plastic film tension changes at this time, the guide roller group can slide in the limit frame through the moving block and adjust its position using the buffer force of the first spring rod to adapt to the tension change and further prevent the plastic film from being torn. The anti-deviation structure, composed of components such as contact rollers, clamping rollers, and vacuum cylinders, further prevents plastic film deviation from both physical limiting and negative pressure adsorption. At the same time, the periodic switching of the adsorption position is achieved through components such as switching plates and cams. Compared with single-position adsorption, it can effectively reduce the deformation and damage to the plastic film caused by long-term adsorption in certain areas, thereby improving the printing quality and service life of the plastic film. Attached Figure Description
[0014] Figure 1 This is a schematic diagram of the overall first-view structure of the present invention; Figure 2 This is a front view of the overall structure of the present invention; Figure 3 This is a schematic diagram of the overall second-view structure of the present invention; Figure 4 This is a schematic diagram of the guide roller position structure of the present invention; Figure 5 This is a schematic diagram of the cooperative structure of the moving block and the limiting frame of the present invention; Figure 6 for Figure 3 Enlarged view of the middle section structure; Figure 7 This is a schematic diagram of the position structure of the second reduction gear of the present invention; Figure 8 This is a schematic diagram of the clamping roller position structure of the present invention; Figure 9 This is a schematic diagram of the internal structure of the contact roller of the present invention; Figure 10 for Figure 9 Enlarged view of point A in the middle.
[0015] In the diagram: 1. Support; 2. Feeding roller; 3. Rewinding roller; 4. Printing mechanism; 5. Tension guiding mechanism; 6. Anti-deviation mechanism; 7. Fixing plate; 8. Contact roller; 9. Limiting frame; 10. Moving block; 11. Guide roller group; 12. Protrusion; 13. Movable frame; 14. Connecting frame; 15. First spring rod; 16. Movable top plate; 17. Synchronization plate; 18. Distance sensor; 19. Motor; 20. First reduction gear group; 21. Pulley group; 22. Cam; 23. Contact block; 24. Pressure relief hole; 25. Second reduction gear group; 26. Second spring rod; 27. Clamping roller; 28. Adsorption hole; 29. Air extraction cylinder; 30. Partition plate; 31. Negative pressure port; 32. First sealing plate; 33. Switching plate; 34. Second sealing plate; 35. Air hole; 36. Insert plate; 37. Isolation plate. Detailed Implementation
[0016] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0017] Example 1 Please see Figures 1-10 The present invention provides a technical solution: A printing device for pharmaceutical packaging plastic film mainly consists of a support 1, a feeding roller 2, a winding roller 3, a tension guiding mechanism 5, a printing mechanism 4, and an anti-deviation mechanism 6. The components cooperate with each other to achieve stable printing of the plastic film.
[0018] The support frame 1, which serves as the supporting frame for the entire device, is made of high-strength aluminum alloy and is constructed into a stable rectangular frame structure through welding and bolting. The four corners of the support frame 1 are equipped with height-adjustable support feet to facilitate maintaining the device's horizontal stability in different ground environments. The feeding roller 2 and the winding roller 3 are arranged opposite each other on both sides of the support frame 1. The feeding roller 2 is used to place unprinted plastic packaging film rolls, and the winding roller 3 is used to collect printed plastic film. Both the feeding roller 2 and the winding roller 3 are rotatably mounted on the support frame 1 via bearings to ensure smooth rotation. The tension guiding mechanism 5 is located inside the support 1 and is the core part for controlling the tension of the plastic film. It includes a fixed plate 7 arranged opposite to each other on the inner side wall of the support 1. The fixed plate 7 is rectangular and fixed to the support 1 by bolts. A guide roller group 11 is symmetrically arranged inside the fixed plate 7. The guide roller group 11 consists of multiple parallel guide rollers. Both ends of each guide roller are rotatably mounted on the fixed plate 7 through bearings. Movable blocks 10 are arranged on both sides of the guide roller group 11. The movable blocks 10 are rectangular block structures. Limiting frames 9 are sleeved and slidably installed on their outer walls. The limiting frames 9 are fixed on the fixed plate 7 and restrict the movement direction of the movable blocks 10, so that the movable blocks 10 can only slide along the direction perpendicular to the plastic film conveying direction. The inner wall of the fixed plate 7 is also provided with evenly distributed protrusions 12. The protrusions 12 are cuboid in shape and are vertically fixed on the inner wall of the fixed plate 7. Several first spring rods 15 are provided on the bottom surface of the protrusions 12. The first spring rod 15 consists of a spring and a telescopic rod. The spring is sleeved on the outside of the telescopic rod. One end of the first spring rod 15 is fixed to the bottom surface of the protrusion 12, and the other end is inserted into the moving block 10 and slidably installed. This design allows the guide roller group 11 to move along the first spring rod 15 through the moving block 10. The spring of the first spring rod 15 provides a buffering force. When the tension of the plastic film changes, the guide roller group 11 can adaptively adjust its position to adapt to the tension change of the plastic film and avoid excessive or insufficient tension from affecting the printing quality.
[0019] A motor 19 is installed on one side of the take-up roller 3. The motor 19 is connected to the rotating shaft of the take-up roller 3 via a coupling, providing rotational power to the take-up roller 3. A synchronization plate 17 is also slidably installed on one side of the take-up roller 3. The synchronization plate 17 is a long strip plate structure, and a movable top plate 16 is provided on one side of it. The movable top plate 16 is perpendicularly connected to the synchronization plate 17 and can slide up and down on one side of the take-up roller 3 together with the synchronization plate 17. A distance sensor 18 is provided on the top surface of the take-up roller 3. The distance sensor 18 is used to detect the thickness change of the plastic film roll on the take-up roller 3. A movable frame 13 is sleeved and slidably installed on the outer wall of the protrusion 12. The movable frame 13 is a rectangular frame structure and can slide up and down along the outer wall of the protrusion 12. The movable frames 13 are connected to each other through a connecting frame 14. The connecting frame 14 is a long strip rod structure that connects the movable frames 13 on both sides into a whole. A toothed plate is provided at one end of both the connecting frame 14 and the synchronizing plate 17. A second reduction gear set 25 is provided on the bracket 1. The second reduction gear set 25 meshes with the connecting frame 14 and the synchronizing plate 17 respectively through the toothed plate. In the initial state, the movable frame 13 limits the guide roller group 11, keeping it immobile. As the take-up roller 3 continuously winds up the plastic film, the thickness of the take-up roll gradually increases, causing the movable top plate 16 to move upward. The movable top plate 16, through the meshing of the toothed plate on the synchronous plate 17 and the second reduction gear set 25, drives the connecting frame 14 to move upward synchronously, thereby causing all the movable frames 13 to move upward, providing elastic stretching space for the guide roller group 11. At this time, the guide roller group 11 can slide within the limiting frame 9 by the moving block 10, using the buffering force of the first spring rod 15 to adapt to changes in the plastic film tension. Simultaneously, the distance sensor 18 detects the distance to the synchronous plate 17 in real time to obtain the changes in the take-up roll thickness. When the detected thickness reaches a certain threshold, the motor 19 is controlled to decelerate to prevent the roll tension from becoming too tight. During the deceleration of the motor 19, the transmission of the second reduction gear set 25 ensures that there is still some room for movement between the guide roller groups 11, further preventing the plastic film from being torn due to excessive tightness.
[0020] The printing mechanism 4, located on top of the support 1, is a key component for printing on the plastic film. The printing mechanism 4 includes a printing frame, a printing roller, an ink supply system, and a printing plate. The printing frame is fixed to the top of the support 1, providing mounting support for other printing components. The printing roller is rotatably mounted on the printing frame via bearings, used to transport the plastic film and apply printing pressure. The ink supply system includes an ink tank, an ink pump, and ink delivery pipes. The ink tank stores the ink required for printing, and the ink pump draws ink from the ink tank and delivers it to the printing plate through the ink delivery pipes. The printing plate is engraved with pharmaceutical information patterns. When the plastic film passes between the printing roller and the printing plate, under printing pressure, the ink is transferred from the printing plate to the plastic film, completing the printing process.
[0021] In use, first, the unprinted plastic packaging film roll is installed on the feed roller 2. One end of the plastic film is pulled out and passed sequentially between the guide roller group 11 of the tension guiding mechanism 5, the printing cylinder of the printing mechanism 4 and the printing plate, and finally fixed on the take-up roller 3. The motor 19 is started and the take-up roller 3 starts to rotate, driving the plastic film to be conveyed from the feed roller 2 to the take-up roller 3. During the conveying process of the plastic film, in the initial state, the guide roller group 11 is limited by the movable frame 13 and is in a fixed state. As the take-up roller 3 continuously winds up the plastic film, the thickness of the take-up roll gradually increases. The movable top plate 16 moves upward under the push of the take-up roll. Through the meshing transmission of the synchronous plate 17 and the second reduction gear set 25, it drives the connecting frame 14 and the movable frame 13 to move upward, releasing the activity space for the guide roller set 11. At this time, if the tension of the plastic film changes, the guide roller set 11 can slide within the limit frame 9 through the moving block 10 and adjust its position using the buffer force of the first spring rod 15 to adapt to the tension change. At the same time, the distance sensor 18 monitors the change in the thickness of the take-up roll in real time. When the thickness reaches the preset threshold, it sends a signal to the control system. The control system controls the motor 19 to decelerate and reduce the winding speed to avoid the tension of the roll being too tight. During the deceleration of the motor 19, the transmission of the second reduction gear set 25 ensures that there is still a certain amount of activity space between the guide roller sets 11, further preventing the plastic film from being torn. When the plastic film passes through the printing mechanism 4, the printing mechanism 4 prints the drug information pattern on the plastic film according to the preset program. Finally, the take-up roller 3 completes the winding.
[0022] Example 2 Please see Figures 1-10 The present invention provides a technical solution: The anti-deviation mechanism 6 includes a contact roller 8 mounted on a fixed plate 7. The contact roller 8 is a cylindrical roller with its axis parallel to the direction of plastic film conveying. Several clamping rollers 27 are mounted on one side of the contact roller 8. The clamping rollers 27 are cylindrical and arranged parallel to the contact roller 8. They are mounted on the fixed plate 7 by a bracket and can rotate around their own axis. The function of the clamping rollers 27 is to press the plastic film onto the surface of the contact roller 8 when the plastic film is being wound up, so that the plastic film fits the contact roller 8 better and avoids deviation. An air extraction cylinder 29 is inserted inside the contact roller 8. The air extraction cylinder 29 has a hollow cylindrical structure, with one end closed and the other end connected to the negative pressure mechanism through an air pipe. A negative pressure port 31 is opened on the air extraction cylinder 29, which creates a negative pressure inside the air extraction cylinder 29. Two rows of adsorption holes 28 are opened on one side of the outer wall of the contact roller 8 and are evenly distributed on the circumferential surface of the contact roller 8. When a negative pressure is formed inside the air extraction cylinder 29, air is drawn into the air extraction cylinder 29 through the adsorption holes 28, thereby generating suction on the surface of the contact roller 8, adsorbing and fixing the plastic film on the contact roller 8, further improving the fixing effect of the plastic film and preventing displacement. An isolation plate 37 is provided between the contact roller 8 and the suction cylinder 29. The isolation plate 37 is a circular plate structure and is fixed on the inner wall of the contact roller 8, dividing the interior of the contact roller 8 into two independent spaces. A second spring rod 26 is inserted and slidably installed inside the contact roller 8. The second spring rod 26 consists of a spring and a telescopic rod. A contact block 23 is provided at the top of the second spring rod 26 and a switching plate 33 is provided at the bottom. The switching plate 33 is a plate structure and an insert plate 36 is symmetrically provided on the bottom surface. The isolation plate 37 is inserted and can be slidably assembled in the through hole on the isolation plate 37. The insert plate 36 has evenly distributed air holes 35, which are used to connect the suction cylinder 29 and the interior space of the contact roller 8. A first sealing plate 32 is provided on both sides of the negative pressure port 31. The first sealing plate 32 is fixed on the suction cylinder 29, and the insert plate 36 and the first sealing plate 32 are slidably assembled. A partition 30 is provided between the contact roller 8 and the suction cylinder 29. The partition 30 is a circular plate structure located between two rows of opposite suction holes 28, further separating the two spaces inside the contact roller 8 so that each space corresponds to a row of suction holes 28. A cam 22 is rotatably mounted on one side of the contact roller 8. The cam 22 is mounted on the fixed plate 7 through a bearing. A pulley group 21 is provided between the cam 22 and the take-up roller 3. The pulley group 21 consists of two pulleys and a belt, which is used to transmit the rotational power of the take-up roller 3 to the cam 22. A second sealing plate 34 is provided on the top surface of the partition plate 37. The second sealing plate 34 is fixed on the partition plate 37. The switching plate 33 and the second sealing plate 34 are slidably assembled. A first reduction gear group 20 is provided between the take-up roller 3 and the pulley group 21. The first reduction gear group 20 is used to reduce the rotational speed of the take-up roller 3 and slow down the rotational speed of the cam 22. The contact roller 8 is divided into two independent spaces by the sealing of the two isolation plates 37 and the partition plate 30. The switching plate 33 can control the connection state between these two spaces and the negative pressure port 31. When the switching plate 33 slides in the second sealing plate 34, the negative pressure port 31 is connected to the first space through the air hole 35. At this time, the row of adsorption holes 28 corresponding to the space generates suction to adsorb the plastic film. When the switching plate 33 slides upward out of the second sealing plate 34, the air hole 35 follows the sliding of the insert plate 36 into the isolation plate 37. At this time, the negative pressure port 31 is connected to the second space. The row of adsorption holes 28 corresponding to the second space generates suction to adsorb the plastic film. The up and down reciprocating movement of the switching plate 33 is achieved by the transmission of the pulley group 21 and the first reduction gear group 20, and by the power of the winding roller 3 driving the cam 22 to periodically push the contact block 23 upward. The top surface of the contact roller 8 is also provided with two rows of pressure relief holes 24 facing each other, and the two rows of pressure relief holes 24 are located on both sides of the second spring rod 26. When the adsorption hole 28 is blocked by the plastic film, excess gas can be replenished into the interior of the contact roller 8 through the pressure relief holes 24 to avoid deformation of the plastic film due to excessive internal pressure. Compared with Example 1, this example focuses on improving the anti-deviation mechanism 6. Example 1 mainly uses the tension guiding mechanism 5 to control the tension of the plastic film to reduce deviation. However, this example adds an anti-deviation structure composed of components such as the contact roller 8, clamping roller 27, and air pump 29. This structure further prevents the plastic film from deviating from both physical limiting and negative pressure adsorption aspects. At the same time, the periodic switching of the adsorption position is achieved through components such as the switching plate 33 and cam 22. Compared with adsorption at a single position, this can effectively reduce the deformation and damage of the plastic film caused by long-term adsorption in certain areas, thereby improving the printing quality and service life of the plastic film. During the plastic film winding process, the plastic film first passes between the clamping roller 27 and the contact roller 8. The clamping roller 27 presses the plastic film onto the surface of the contact roller 8, achieving initial positioning. When the winding roller 3 rotates, it drives the cam 22 to rotate through the transmission of the first reduction gear set 20 and the pulley set 21. During the rotation of the cam 22, it periodically pushes the contact block 23. The contact block 23 drives the switching plate 33 to move up and down reciprocally through the second spring rod 26. When the switching plate 33 slides down and is located inside the second sealing plate 34, the air hole 35 connects with the negative pressure port 31 to the first space. The row of suction holes 28 corresponding to this space generates suction, adsorbing the plastic film onto the surface of the contact roller 8. When the switching plate 33 slides up and slides out of the second sealing plate 34, the air hole 35 connects with the negative pressure port 31 to the second space. The row of suction holes 28 corresponding to the second space generates suction. The suction force adsorbs the plastic film. Through the periodic up-and-down movement of the switching plate 33, the two rows of suction holes 28 alternately adsorb the plastic film, avoiding deformation caused by prolonged local stress on the plastic film. During the adsorption process, when the suction holes 28 are blocked by the plastic film, the air inside the contact roller 8 cannot be discharged, and the pressure gradually increases. At this time, the excess gas is discharged or replenished through the pressure relief hole 24 to maintain the pressure balance inside the contact roller 8, prevent the plastic film from deforming due to excessive pressure, and ensure that the plastic film remains flat during printing and winding, effectively preventing deviation.
[0023] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.
[0024] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention.
Claims
1. A printing apparatus for pharmaceutical packaging plastic film, comprising a support (1), and a feed roller (2) and a take-up roller (3) disposed on the support (1) and arranged opposite to each other, characterized in that: The bracket (1) is also provided with a tension guiding mechanism (5), the top of the bracket (1) is also provided with a printing mechanism (4), the top of the bracket (1) is also provided with a printing mechanism (4), and the bracket (1) is also provided with an anti-deviation mechanism (6).
2. The printing apparatus for pharmaceutical packaging plastic film according to claim 1, characterized in that: The tension guiding mechanism (5) includes a fixed plate (7) arranged opposite to each other on the bracket (1). A guide roller group (11) is symmetrically arranged inside the fixed plate (7). A movable block (10) is arranged on both sides of the guide roller group (11). A limit frame (9) is sleeved and slidably installed on the outer wall of the movable block (10). The limit frame (9) is arranged on the fixed plate (7). The inner wall of the fixed plate (7) is also provided with evenly distributed protrusions (12). Several first spring rods (15) are arranged on the ground of the protrusions (12). The first spring rods (15) are inserted into the movable block (10) and slidably installed.
3. The printing apparatus for pharmaceutical packaging plastic film according to claim 2, characterized in that: A motor (19) is provided on one side of the take-up roller (3), and a synchronization plate (17) is also slidably installed on one side of the take-up roller (3). A movable top plate (16) is provided on one side of the synchronization plate (17), and a distance sensor (18) is provided on the top surface of the take-up roller (3).
4. The printing apparatus for pharmaceutical packaging plastic film according to claim 2, characterized in that: A movable frame (13) is fitted and slidably installed on the outer wall of the protrusion (12), and the movable frames (13) are connected to each other through a connecting frame (14). The connecting frame (14) is connected to one end of the synchronization plate (17).
5. The printing apparatus for pharmaceutical packaging plastic film according to claim 4, characterized in that: The movable frame (13) has a toothed plate at one end and the second reduction gear set (25) at one end. The bracket (1) has a second reduction gear set (25) on it, and the second reduction gear set (25) meshes with the connecting frame (14) and the synchronous plate (17) respectively through the toothed plate.
6. The printing apparatus for pharmaceutical packaging plastic film according to claim 5, characterized in that: The anti-deviation mechanism (6) includes a contact roller (8) disposed on a fixed plate (7), and a plurality of clamping rollers (27) are disposed on one side of the contact roller (8).
7. The printing apparatus for pharmaceutical packaging plastic film according to claim 6, characterized in that: An air extraction cylinder (29) is inserted inside the contact roller (8), and the air extraction cylinder (29) is connected to the negative pressure mechanism through an air pipe. A negative pressure port (31) is opened on the air extraction cylinder (29), and two rows of adsorption holes (28) facing each other are opened on one side of the outer wall of the contact roller (8).
8. The printing apparatus for pharmaceutical packaging plastic film according to claim 7, characterized in that: A partition plate (37) is provided between the contact roller (8) and the suction cylinder (29). A second spring rod (26) is inserted into and slidably installed inside the contact roller (8). A contact block (23) is provided at the top of the second spring rod (26). A switching plate (33) is provided at the bottom end of the second spring rod (26). An insert plate (36) is symmetrically provided on the bottom surface of the switching plate (33). The partition plate (37) is inserted into the insert plate (36) and slidably assembled. Air holes (35) are evenly distributed on the insert plate (36). Air holes (35) are provided on both sides of the negative pressure port (31). There is a first sealing plate (32), and the insertion plate (36) is slidably assembled with the first sealing plate (32). A partition plate (30) is provided between the contact roller (8) and the suction cylinder (29), and the partition plate (30) is located between two rows of suction holes (28) that are opposite to each other. A cam (22) is rotatably installed on one side of the contact roller (8), and a pulley group (21) is provided between the cam (22) and the winding roller (3). A second sealing plate (34) is provided on the top surface of the partition plate (37), and the switching plate (33) is slidably assembled with the second sealing plate (34).
9. The printing apparatus for pharmaceutical packaging plastic film according to claim 8, characterized in that: The top surface of the contact roller (8) is also provided with two rows of pressure relief holes (24) that are opposite to each other, and the two rows of pressure relief holes (24) are located on both sides of the second spring rod (26).
10. The printing apparatus for pharmaceutical packaging plastic film according to claim 8, characterized in that: A first reduction gear set (20) is provided between the take-up roller (3) and the pulley set (21).