Film winding and unwinding mechanism and digital film writing device
By using a tension sensor and controller to adjust the motor speed in the film rewinding and unrewinding mechanism, the problem of untimely film tension adjustment is solved, ensuring stable film transportation within the appropriate tension range and avoiding deformation and breakage.
Patent Information
- Application Number
- CN202421515047.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-28
- Publication Date
- 2025-09-16
- Estimated Expiration
- 2034-06-28
AI Technical Summary
The film rewinding and unwinding mechanism in the prior art cannot adjust the film tension in time, resulting in poor reliability and stability in film transportation and rewinding. Too little tension affects transportation, while too much tension causes deformation or breakage.
The film unwinding tension sensor and film rewinding tension sensor are used to detect the film tension in real time, and the speed of the film unwinding motor and film rewinding motor are adjusted through the controller to keep the film transported within the appropriate tension range.
The film can be transported stably within a suitable tension range, deformation and breakage can be avoided, and the reliability and stability of transportation can be improved.
Smart Images
Figure CN223342027U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of digital films, in particular to a film retracting and unreeling mechanism and a digital film writing device. Background Art
[0002] With the development of the internet and big data technologies, global data is exploding, and data storage has become a research hotspot. Currently, digital film and glass media are suitable for long-term offline data storage. Unlike hard drives and optical disks, which rely on rotational access, digital film and glass media use rectangular dot matrix storage to maximize the storage area of media like film and glass, achieving massive storage capacity.
[0003] The film unwinding and rewinding mechanism of a digital film writing device includes a film unwinding assembly and a film rewinding assembly. During operation, the unwinding and rewinding assemblies transport film at a constant speed. During this process, the diameter of the film wound on the unwinding and rewinding assemblies continuously changes, and accordingly, the film tension in the unwinding and rewinding assemblies also changes. However, existing unwinding and rewinding mechanisms are unable to adjust the film tension in a timely manner. Excessive film tension can affect the reliability and stability of film transport and rewinding. Excessive film tension can cause irreversible deformation and, in severe cases, even break the film. Utility Model Content
[0004] The purpose of the utility model is to provide a film retracting and unreeling mechanism and a digital film writing device, which can timely adjust the tension of the film during transportation, avoid film deformation and breakage, and ensure that the film is always transported within an appropriate tension range.
[0005] To achieve this purpose, the present invention adopts the following technical solutions:
[0006] A film-reeling and -unreeling mechanism comprises a substrate and a film-reeling assembly, a film-reeling assembly, a film-reeling tension sensor and a film-reeling tension sensor arranged on the substrate; wherein,
[0007] The film placing assembly and the film collecting assembly are spaced apart;
[0008] The film unloading assembly includes a film unloading motor and a film unloading spindle, the housing of the film unloading motor is fixed on the base plate, and the film unloading spindle is fixed on the output shaft of the film unloading motor;
[0009] The film collection assembly includes a film collection motor and a film collection spindle, the housing of the film collection motor is fixed on the base plate, and the film collection spindle is fixed on the output shaft of the film collection motor;
[0010] The first end of the film is connected to and wound on the film unwinding spindle, and the second end of the film is connected to and wound on the film winding spindle. The film released from the film unwinding spindle is wound around the film unwinding tension sensor and the film winding tension sensor in sequence and then wound onto the film winding spindle. The film unwinding tension sensor is used to detect the tension of the film released by the film unwinding spindle, and the film winding tension sensor is used to detect the tension of the film to be wound onto the film winding spindle.
[0011] Preferably, it further includes a guide assembly, wherein the guide assembly includes a first guide shaft and a second guide shaft provided on the base plate; wherein,
[0012] The first guide shafts are arranged in pairs below the film unloading tension sensors, and the film unloading tension sensors and the two first guide shafts are distributed in a triangle shape;
[0013] The second guide shafts are arranged in pairs below the film receiving tension sensor, and the film receiving tension sensor and the two second guide shafts are distributed in a triangle shape;
[0014] The film released from the film unwinding spindle is sequentially wound around one of the first guide shafts, the film unwinding tension sensor, another first guide shaft, one of the second guide shafts, the film taking-up tension sensor, another second guide shaft, and then wound onto the film taking-up spindle.
[0015] Preferably, it also includes a film unloading ultrasonic sensor and a film rewinding ultrasonic sensor arranged on the substrate, the film unloading ultrasonic sensor is used to detect the rewinding amount of the film on the film unloading spindle, and the film rewinding ultrasonic sensor is used to detect the rewinding amount of the film on the film rewinding spindle.
[0016] Preferably, the film placing assembly further comprises a film placing tray, the film placing tray is fixedly connected to the output shaft of the film placing motor, and the film placing spindle is arranged on the film placing tray;
[0017] The film receiving assembly further includes a film receiving tray, which is fixedly connected to the output shaft of the film receiving motor, and the film receiving spindle is arranged on the film receiving tray.
[0018] Preferably, a first connecting shaft is provided on a side of the film placing tray facing away from the film placing spindle, and the first connecting shaft is fixedly connected to the output shaft of the film placing motor;
[0019] A second connecting shaft is provided on the side of the film receiving tray facing away from the film receiving spindle, and the second connecting shaft is fixedly connected to the output shaft of the film receiving motor.
[0020] Preferably, the first connecting shaft is fixedly connected to the output shaft of the film unwinding motor via a first coupling, and the second connecting shaft is fixedly connected to the output shaft of the film taking-up motor via a second coupling.
[0021] Preferably, a first through hole is provided on the film placing tray, and a second through hole is provided on the film receiving tray.
[0022] Preferably, the film-unloading spindle is further provided with a first buckle for clamping the film, and the film-receiving spindle is further provided with a second buckle for clamping the film.
[0023] Preferably, a first connecting frame is fixed on the housing of the film unloading motor, and the housing of the film unloading motor is fixed on the base plate through the first connecting frame;
[0024] A second connecting frame is fixed on the housing of the film-collecting motor, and the housing of the film-collecting motor is fixed on the base plate through the second connecting frame.
[0025] A digital film writing device, comprising any of the film retracting and unreeling mechanisms described above, further comprising:
[0026] The film grabbing gear mechanism comprises a film grabbing gear and a driving motor, wherein the housing of the driving motor is fixed on the base plate, the film grabbing gear is fixed to the output shaft of the driving motor, and the film grabbing gear is meshed with the tooth holes of the film.
[0027] Beneficial effects:
[0028] The film rewinding mechanism provided by the utility model is characterized in that the film released from the unwinding spindle is sequentially wound around the unwinding tension sensor and the take-up tension sensor before being rewound onto the take-up spindle. During operation, the unwinding motor and the take-up motor rotate simultaneously, releasing the film wound on the unwinding spindle, which is then conveyed and rewound onto the take-up spindle after passing through the unwinding sensor and the take-up sensor in sequence. During this process, the unwinding tension sensor detects the tension of the film released by the unwinding spindle in real time, and the take-up tension sensor detects the tension of the film about to be rewound onto the take-up spindle in real time. Based on the tension values detected by the unwinding tension sensor and the take-up tension sensor, the output shaft speeds of the unwinding motor and the take-up motor are adjusted accordingly. The film is always conveyed within an appropriate tension range, and the tension during film transportation is adjusted in a timely manner to prevent film deformation and breakage.
[0029] The digital film writing device provided by the utility model applies the above-mentioned film retracting and unreeling mechanism, which can timely adjust the tension of the film during transportation, avoid film deformation and breaking, and ensure that the film is always transported within an appropriate tension range. BRIEF DESCRIPTION OF THE DRAWINGS
[0030] Figure 1This is a structural diagram of the digital film writing device provided by the utility model;
[0031] Figure 2 This is a structural diagram of the sheet placing assembly provided by the utility model;
[0032] Figure 3 It is a structural schematic diagram of the film collecting assembly provided by the utility model.
[0033] In the picture:
[0034] 1. Base plate; 11. First guide shaft; 12. Second guide shaft; 13. First connecting frame; 14. Second connecting frame; 15. Third guide shaft; 16. Fourth guide shaft;
[0035] 2. Film unloading assembly; 21. Film unloading motor; 22. Film unloading spindle; 221. First buckle; 23. Film unloading tray; 231. First connecting shaft; 232. First through hole; 24. First coupling;
[0036] 3. Film collection assembly; 31. Film collection motor; 32. Film collection spindle; 321. Second buckle; 33. Film collection tray; 331. Second connecting shaft; 332. Second through hole; 34. Second coupling;
[0037] 41. Unwinding tension sensor; 42. Rewinding tension sensor;
[0038] 51. Film unloading ultrasonic sensor; 52. Film receiving ultrasonic sensor;
[0039] 6. Grabbing gear mechanism;
[0040] 7. Buffer mechanism;
[0041] 8. Exposure window and position adjustment mechanism. DETAILED DESCRIPTION
[0042] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all of its components.
[0043] In the description of this utility model, unless otherwise specified or limited, the terms "connected," "connect," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.
[0044] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.
[0045] In the description of this embodiment, the terms "upper," "lower," "right," and other orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely for ease of description and simplified operation. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meaning.
[0046] This embodiment provides a sheet retracting and unfolding mechanism. Figures 1 to 3 As shown, the film retracting and unfolding mechanism includes
[0047] The substrate 1 includes a film unwinding assembly 2, a film take-up assembly 3, a film unwinding tension sensor 41, and a film take-up tension sensor 42. The film unwinding assembly 2 and the film take-up assembly 3 are spaced apart. The film unwinding assembly 2 includes a film unwinding motor 21 and a film unwinding spindle 22. The housing of the film unwinding motor 21 is fixed to the substrate 1, and the film unwinding spindle 22 is fixed to the output shaft of the film unwinding motor 21. The film take-up assembly 3 includes a film take-up motor 31 and a film take-up spindle 32. The housing of the film take-up motor 31 is fixed to the substrate 1, and the film take-up spindle 32 is fixed to the output shaft of the film take-up motor 31. The first end of the film is connected to and taken up by the film unwinding spindle 22, and the second end of the film is connected to and taken up by the film take-up spindle 32. The film released by the unwinding spindle 22 is wound around the unwinding tension sensor 41 and the winding tension sensor 42 in sequence and then wound onto the winding spindle 32. The unwinding tension sensor 41 is used to detect the tension of the film released by the unwinding spindle 22, and the winding tension sensor 42 is used to detect the tension of the film to be wound onto the winding spindle 32.
[0048] In this embodiment, the film released from the unwinding spindle 22 is sequentially wound around the unwinding tension sensor 41 and the take-up tension sensor 42 before being reeled onto the take-up spindle 32. During operation, the unwinding motor 21 and the take-up motor 31 rotate simultaneously, releasing the film wound on the unwinding spindle 22. The film is then conveyed and reeled onto the take-up spindle 32 after passing through the unwinding and take-up sensors. During this process, the unwinding tension sensor 41 detects the tension of the film released from the unwinding spindle 22 in real time, while the take-up tension sensor 42 detects the tension of the film about to be reeled onto the take-up spindle 32 in real time. Based on the tension values detected by the unwinding tension sensor 41 and the take-up tension sensor 42, the output shaft speeds of the unwinding and take-up motors 21 and 31 are adjusted accordingly. This ensures that the film is always conveyed within an appropriate tension range, and timely adjustments are made to the film tension during transportation to prevent film deformation and breakage.
[0049] Specifically, the film unwinding and rewinding mechanism includes a controller, to which the unwinding and rewinding tension sensors 41 and 42 are respectively connected in communication. The unwinding and rewinding motors 21 and 31 are also respectively connected in communication with the controller. Specifically, the unwinding and rewinding tension sensors 41 and 42 transmit their detected tension values to the controller, which then adjusts the speeds of the unwinding and rewinding motors 21 and 31 accordingly.
[0050] Specifically, the unwinding tension sensor 41 detects the film tension released by the unwinding spindle 22 in real time, which in turn adjusts the speed of the unwinding motor 21. The take-up tension sensor 42 detects the film tension released by the take-up spindle 32 in real time, which in turn adjusts the speed of the take-up motor 31. For example, when the unwinding tension sensor 41 detects that the film tension released by the unwinding spindle 22 is excessive, the controller promptly increases the speed of the unwinding motor 21. When the unwinding tension sensor 41 detects that the film tension released by the unwinding spindle 22 is too low, the controller promptly reduces the speed of the unwinding motor 21. When the take-up tension sensor 42 detects that the film tension released by the take-up spindle 32 is excessive, the controller promptly reduces the speed of the take-up motor 31. When the take-up tension sensor 42 detects that the film tension released by the take-up spindle 32 is too low, the controller promptly increases the speed of the take-up motor 31.
[0051] Optionally, the controller can be configured as a PCB control board.
[0052] Furthermore, the film rewinding and unwinding mechanism includes a guide assembly, which comprises a first guide shaft 11 and a second guide shaft 12 disposed on the base plate 1. The first guide shafts 11 are arranged in pairs below the film unwinding tension sensor 41, with the two first guide shafts 11 arranged in a triangular configuration. The second guide shafts 12 are arranged in pairs below the film take-up tension sensor 42, with the two second guide shafts 12 arranged in a triangular configuration. The film released from the film unwinding spindle 22 is sequentially wound around one of the first guide shafts 11, the film unwinding tension sensor 41, the other first guide shaft 11, one of the second guide shafts 12, the take-up tension sensor 42, and the other second guide shaft 12 before being reeled onto the take-up spindle 32.
[0053] By providing the first guide shafts 11, the film is sequentially wound around one of the first guide shafts 11, the unwinding tension sensor 41, and the other first guide shaft 11, thereby ensuring that the unwinding tension sensor 41 is in close contact with the film surface, further ensuring the reliability and effectiveness of tension detection by the unwinding tension sensor 41. By providing the second guide shafts 12, the film is sequentially wound around one of the second guide shafts 12, the take-up tension sensor 42, and the other second guide shaft 12, thereby ensuring that the take-up tension sensor 42 is in close contact with the film surface, further ensuring the reliability and effectiveness of tension detection by the take-up tension sensor 42.
[0054] Furthermore, the guide assembly includes a third guide shaft 15 and a fourth guide shaft 16 disposed on the base plate 1. The film released from the film unwinding spindle 22 is sequentially wound around the third guide shaft 15, one of the first guide shafts 11, the film unwinding tension sensor 41, the other first guide shaft 11, one of the second guide shafts 12, the film taking-up tension sensor 42, the other second guide shaft 12, and the fourth guide shaft 16 before being rewound to the film taking-up spindle 32.
[0055] In this embodiment, the film unwinding and rewinding mechanism further includes a film unwinding ultrasonic sensor 51 and a film rewinding ultrasonic sensor 52 disposed on the base plate 1. The film unwinding ultrasonic sensor 51 is used to detect the amount of film rewound on the film unwinding spindle 22, and the film rewinding ultrasonic sensor 52 is used to detect the amount of film rewound on the film rewinding spindle 32. Specifically, the film unwinding ultrasonic sensor 51 and the film rewinding ultrasonic sensor 52 are respectively communicatively connected to a controller. Specifically, the film unwinding ultrasonic sensor 51 and the film rewinding ultrasonic sensor 52 transmit the detected film rewinding amounts on the film unwinding spindle 22 and the film rewinding spindle 32, respectively, to the controller. The controller can also adjust the rotational speeds of the film unwinding motor 21 and the film rewinding motor 31 accordingly based on the acquired film rewinding amounts on the film unwinding spindle 22 and the film rewinding spindle 32.
[0056] Specifically, the film unwinding assembly 2 also includes a film unwinding tray 23, which is fixedly connected to the output shaft of the film unwinding motor 21. The film unwinding spindle 22 is mounted on the film unwinding tray 23. The film unwinding tray 23 provides reliable support for the film wound around the film unwinding spindle 22. The film take-up assembly 3 also includes a film take-up tray 33, which is fixedly connected to the output shaft of the film take-up motor 31. The film take-up spindle 32 is mounted on the film take-up tray 33. The film take-up tray 33 provides reliable support for the film wound around the film take-up spindle 32.
[0057] Furthermore, a first connecting shaft 231 is provided on the side of the film unloading tray 23 facing away from the film unloading spindle 22, and the first connecting shaft 231 is fixedly connected to the output shaft of the film unloading motor 21. A second connecting shaft 331 is provided on the side of the film receiving tray 33 facing away from the film receiving spindle 32, and the second connecting shaft 331 is fixedly connected to the output shaft of the film receiving motor 31.
[0058] Furthermore, the first connecting shaft 231 is fixedly connected to the output shaft of the film unwinding motor 21 via the first coupling 24, and the second connecting shaft 331 is fixedly connected to the output shaft of the film rewinding motor 31 via the second coupling 34. As a reliable and efficient torque transmission device, couplings have high sensitivity, high transmission efficiency, long service life, good shock absorption performance, and good corrosion resistance, and are widely used in connecting shafts.
[0059] Furthermore, a first through hole 232 is formed on the film placing tray 23, and a second through hole 332 is formed on the film receiving tray 33. The first through hole 232 and the second through hole 332 can reduce the weight of the film placing tray 23 and the film receiving tray 33.
[0060] Furthermore, the film-unloading spindle 22 is provided with a first buckle 221 for clamping the film, thereby fixing the film-unloading spindle 22 to the first end of the film. The film-collecting spindle 32 is also provided with a second buckle 321 for clamping the film, thereby fixing the film-unloading spindle 22 to the second end of the film.
[0061] Furthermore, a first connecting frame 13 is fixed to the housing of the film unwinding motor 21, and the housing of the film unwinding motor 21 is fixed to the base plate 1 via the first connecting frame 13. A second connecting frame 14 is fixed to the housing of the film take-up motor 31, and the housing of the film take-up motor 31 is fixed to the base plate 1 via the second connecting frame 14. The provision of the first connecting frame 13 and the second connecting frame 14 can effectively secure the housings of the film unwinding motor 21 and the film take-up motor 31 to the base plate 1.
[0062] Continue to refer to Figure 1 As shown, this embodiment also provides a digital film writing device, which includes the above-mentioned film reeling and unreeling mechanism. The digital film writing device also includes a film grabbing gear mechanism 6. Specifically, the film grabbing gear mechanism 6 includes a film grabbing gear and a drive motor. The housing of the drive motor is fixed to the base plate 1, and the film grabbing gear is fixed to the output shaft of the drive motor. The film grabbing gear meshes with the perforations of the film. Specifically, when the device is operating normally, the drive motor drives the film grabbing gear to rotate at a constant speed. The rotation of the film grabbing gear drives the film to move through the meshing between the gears of the film. In conjunction with the film unloading assembly 2 and the film reeling assembly 3, the film can be transported more reliably and efficiently.
[0063] Furthermore, the digital film writing device includes a buffer mechanism 7, which reduces the sudden tension on the film when the device is started and stopped. This prevents the film from being deformed or even broken by the sudden tension caused by the sudden acceleration and deceleration of the multiple motors. This provides primary protection for the film.
[0064] Furthermore, the digital film writing device also includes an exposure window and position adjustment mechanism 8. This mechanism consists of the exposure window, a backplate, and a forward and backward adjustment slide. The exposure window is fixed to the base plate 1, the backplate is fixed to the slide, and the slide is fixed to the base plate 1. This allows for adjustable relative positions between the backplate and the exposure window. During operation, the film is positioned between the exposure window and the backplate. Adjustment here controls the distance between the exposure window and the backplate, thereby controlling the tightness of the film at this point. This ensures both film flatness and moderate pressure for smooth operation.
[0065] It is understandable that for connection methods not explicitly described herein, common connection methods such as threaded connection, welding or bonding may be selected as needed.
[0066] Obviously, the above-described embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention and are not intended to limit the manner in which the present invention is to be implemented. A person skilled in the art would be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is not necessary and impossible to enumerate all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.
Claims
1. A sheet retracting and unfolding mechanism, characterized in that: It comprises a substrate (1), and a film placing assembly (2), a film collecting assembly (3), a film placing tension sensor (41), and a film collecting tension sensor (42) arranged on the substrate (1); wherein, The film placing component (2) and the film collecting component (3) are arranged at intervals; The film unloading assembly (2) comprises a film unloading motor (21) and a film unloading spindle (22), the housing of the film unloading motor (21) is fixed on the substrate (1), and the film unloading spindle (22) is fixed on the output shaft of the film unloading motor (21); The film collection assembly (3) comprises a film collection motor (31) and a film collection spindle (32), the housing of the film collection motor (31) is fixed on the base plate (1), and the film collection spindle (32) is fixed on the output shaft of the film collection motor (31); The first end of the film is connected to and wound on the film unwinding spindle (22), and the second end of the film is connected to and wound on the film taking-up spindle (32). The film released from the film unwinding spindle (22) is wound around the film unwinding tension sensor (41) and the film taking-up tension sensor (42) in sequence and then wound onto the film taking-up spindle (32). The film unwinding tension sensor (41) is used to detect the tension of the film released from the film unwinding spindle (22), and the film taking-up tension sensor (42) is used to detect the tension of the film to be wound onto the film taking-up spindle (32).
2. The sheet retracting and unfolding mechanism according to claim 1, characterized in that: It also includes a guide assembly, the guide assembly including a first guide shaft (11) and a second guide shaft (12) arranged on the base plate (1); wherein, The first guide shafts (11) are arranged in pairs below the sheet-unloading tension sensors (41), and the sheet-unloading tension sensors (41) and the two first guide shafts (11) are distributed in a triangular shape; The second guide shafts (12) are arranged in pairs below the film receiving tension sensor (42), and the film receiving tension sensor (42) and the two second guide shafts (12) are distributed in a triangular shape; The film released from the film unwinding spindle (22) is sequentially wound around one of the first guide shafts (11), the film unwinding tension sensor (41), another of the first guide shafts (11), one of the second guide shafts (12), the film receiving tension sensor (42), another of the second guide shafts (12), and then wound onto the film receiving spindle (32).
3. The sheet retracting and unfolding mechanism according to claim 1, characterized in that: It also includes a film unwinding ultrasonic sensor (51) and a film rewinding ultrasonic sensor (52) arranged on the substrate (1), wherein the film unwinding ultrasonic sensor (51) is used to detect the amount of film rewinding on the film unwinding spindle (22), and the film rewinding ultrasonic sensor (52) is used to detect the amount of film rewinding on the film rewinding spindle (32).
4. The sheet retracting and unfolding mechanism according to claim 1, characterized in that: The film placing assembly (2) further includes a film placing tray (23), wherein the film placing tray (23) is fixedly connected to the output shaft of the film placing motor (21), and the film placing spindle (22) is arranged on the film placing tray (23); The film receiving assembly (3) further comprises a film receiving tray (33), wherein the film receiving tray (33) is fixedly connected to the output shaft of the film receiving motor (31), and the film receiving spindle (32) is arranged on the film receiving tray (33).
5. The sheet retracting and unfolding mechanism according to claim 4, characterized in that: A first connecting shaft (231) is provided on the side of the film placing tray (23) facing away from the film placing spindle (22), and the first connecting shaft (231) is fixedly connected to the output shaft of the film placing motor (21); A second connecting shaft (331) is provided on the side of the film receiving tray (33) facing away from the film receiving main shaft (32), and the second connecting shaft (331) is fixedly connected to the output shaft of the film receiving motor (31).
6. The sheet retracting and unfolding mechanism according to claim 5, characterized in that: The first connecting shaft (231) is fixedly connected to the output shaft of the film unwinding motor (21) via a first coupling (24), and the second connecting shaft (331) is fixedly connected to the output shaft of the film collecting motor (31) via a second coupling (34).
7. The sheet retracting and unfolding mechanism according to claim 4, characterized in that: The film placing tray (23) is provided with a first through hole (232), and the film receiving tray (33) is provided with a second through hole (332).
8. The sheet retracting and unfolding mechanism according to claim 1, characterized in that: The film-unloading spindle (22) is further provided with a first buckle (221) for clamping the film, and the film-receiving spindle (32) is further provided with a second buckle (321) for clamping the film.
9. The sheet retracting and unfolding mechanism according to claim 1, characterized in that: A first connecting frame (13) is fixed to the housing of the film unloading motor (21), and the housing of the film unloading motor (21) is fixed to the substrate (1) via the first connecting frame (13); A second connecting frame (14) is fixed to the housing of the film-collecting motor (31), and the housing of the film-collecting motor (31) is fixed to the base plate (1) via the second connecting frame (14).
10. A digital film writing device, characterized in that: The sheet retracting and unfolding mechanism according to any one of claims 1 to 9 further comprises: The film grabbing gear mechanism (6) comprises a film grabbing gear and a driving motor, wherein the housing of the driving motor is fixed on the base plate (1), the film grabbing gear is fixed to the output shaft of the driving motor, and the film grabbing gear is meshed with the tooth holes of the film.