Manual fixed-length cutting device

Abstract

The utility model discloses a manual fixed-length cutting device, which belongs to the technical field of cutting devices and comprises a base, and a fixed-length mechanism is slidably connected to the outside of a rotating shaft. The rear end of the rotating shaft is fixedly connected with a transmission mechanism, and the top end of the fixing shaft is rotationally connected with an opposite mechanism. The two sides of the fixing shaft are slidably connected with shielding mechanisms, and a reset mechanism is arranged at the bottom of the fixing shaft. Through the length fixing mechanism, the cutting length can be accurately set, operation is easy and convenient, dependence on experience of operators is not needed, and high cutting precision is guaranteed; efficient linkage of power transmission is achieved through the design of the transmission mechanism, rotation of the rotating shaft can synchronously drive the third shaft to rotate, operation is convenient and fast, and practicability is high; the opposite mechanism achieves synchronous opposite or opposite movement of the two racks through meshing of fluted discs and the racks, the structure is simple, cost is low, mechanical transmission is completely relied on, and complex control is not needed.

Description

Technical Field

[0001] This utility model relates to the field of cutting device technology, and in particular to a manual fixed-length cutting device. Background Technology

[0002] In the materials processing industry, cutting is a key process that remains irreplaceable for small businesses and specific processing scenarios (such as the initial processing of materials for handmade crafts and small workshops).

[0003] However, traditional manual cutting methods, such as using scissors or knives, rely heavily on the operator's experience and manual operation, resulting in low cutting length accuracy and difficulty in meeting the market's increasingly demanding requirements for product quality. Although some more advanced manual cutting equipment has attempted to introduce a fixed-length structure, these devices are often complex in structure, expensive, and have problems such as inconvenient adjustment, easy failure, and difficult maintenance.

[0004] Therefore, there is an urgent need to provide a manual fixed-length cutting device to solve the above problems. Utility Model Content

[0005] The technical problem to be solved by this utility model is to overcome the shortcomings of the prior art and provide a manual fixed-length cutting device.

[0006] To solve the above technical problems, the present invention provides a manual fixed-length cutting device, including a base, a conveyor belt for conveying the workpiece to be processed is rotatably connected inside the base, a rotating shaft is rotatably connected to one side of the base, a fixed-length mechanism is slidably connected to the outside of the rotating shaft, and a blade for cutting the workpiece is fixedly connected to the bottom of the fixed-length mechanism.

[0007] The base is fixedly connected to a fixed shaft at its top, a baffle for blocking is rotatably connected to the bottom of the fixed shaft, a transmission mechanism is fixedly connected to the rear end of the rotating shaft, and an opposing mechanism is rotatably connected to the top end of the fixed shaft.

[0008] The fixed shaft is slidably connected to both sides by a shielding mechanism, and a reset mechanism is provided at the bottom of the fixed shaft.

[0009] The present invention is further configured such that: the fixed length mechanism includes a sleeve slidably connected to the outside of the rotating shaft; a protrusion slidably connected to the outside of the rotating shaft is fixedly connected to the outside of the sleeve; a bolt with its front end in contact with the rotating shaft is rotatably connected to the outward side of the sleeve; a long rod with its bottom fixedly connected to the blade is fixedly connected to the inward side of the sleeve; and a handle is fixedly connected to the other end of the long rod.

[0010] The main function of the length-fixing mechanism, as described above, is to stabilize the blade and precisely set the required cutting length. During operation, the desired cutting length is positioned by sliding the sleeve on the rotating shaft to the desired location. Once the sleeve reaches the target position, the rotating bolt ensures that its front end is in close contact with the rotating shaft, thus fixing the sleeve's position. During cutting, simply gripping the handle drives the long rod to deflect, which in turn causes the blade to rotate around the rotating shaft, achieving the cutting action. Simultaneously, the deflection of the handle, long rod, and blade causes the sleeve to deflect, which in turn causes the protrusion to deflect, and the rotating shaft to rotate. This process is both fast and convenient, with a simple and practical design and low cost. This mechanism ensures high precision in cutting length without relying on the operator's experience or manual accuracy, and it is easy to adjust, has a low failure rate, and is relatively easy to maintain.

[0011] The present invention is further configured as follows: the transmission mechanism includes a helical gear disk fixedly connected to the rear end of the rotating shaft; a plurality of first brackets are fixedly connected to the top of the base; two of the first brackets are rotatably connected to the rotating shaft; the other two of the first brackets are fixedly connected to a fixed shaft; a second bracket is fixedly connected to the top of the first bracket located at the rear end of the rotating shaft; a second shaft is rotatably connected inside the second bracket; a helical gear disk is also fixedly connected to the outside of the second shaft; the two helical gear disks mesh with each other; a transmission wheel is also fixedly connected to the outside of the second shaft; a third bracket is fixedly connected to the top of the first bracket located on one side of the fixed shaft; a third shaft is rotatably connected inside the third bracket and rotatably connected to the fixed shaft; a transmission wheel is also fixedly connected to the outside of the third shaft; and a transmission belt connects the two transmission wheels.

[0012] Through the above technical solution, the function of the transmission mechanism is to use a series of precise mechanical transmissions to cause the third shaft to rotate. Specifically, when the deflection handle is operated to cause the rotating shaft to rotate, this initial power is transmitted sequentially to the helical gear plate, which in turn drives the other helical gear plate meshing with it to rotate. This rotational kinetic energy is then transmitted to the second shaft, and through the linkage of the transmission wheel and the transmission belt, it drives another transmission wheel and finally the third shaft to rotate. This series of smooth mechanical transmission processes ensures that while the deflection handle drives the rotating shaft to rotate, it can also effectively drive the third shaft to rotate synchronously. This design is not only simple to operate, practical and efficient, but also achieves two goals in power transmission, fully demonstrating its ingenuity and practicality.

[0013] The present invention is further configured such that: the opposing mechanism includes a gear disk fixedly connected to the bottom of the shaft three, and two first brackets located on both sides of the fixed shaft are fixedly connected to the inner side of the brackets, and racks that mesh with the sides of the gear disk are slidably connected in the two racks, and the two racks are designed to be centrally symmetrical about the gear disk.

[0014] Through the above technical solution, the function of the opposing mechanism is to control the relative approach or distance movement of the two racks within the limiting cylinder; when the shaft rotates, it drives the gear plate to rotate synchronously, and this rotation in turn causes the two racks to move synchronously towards or away from each other within the limiting cylinder; this process is not only convenient to operate and highly practical, but also relies entirely on mechanical transmission to achieve this, without the need for complex control, thus resulting in low cost and simple mechanism structure; this design effectively achieves the expected effect through mechanical linkage, which is both economical and efficient.

[0015] The present invention is further configured such that: the blocking mechanism includes two collars slidably connected to both sides of the fixed shaft, the two collars are fixedly connected to two racks respectively, the front ends of the two collars are fixedly connected to a front stop block that contacts the front end of the baffle, and the rear ends of the two collars are fixedly connected to a rear stop block that contacts the rear end of the baffle.

[0016] Through the above technical solution, the blocking mechanism, by deflecting the rotating shaft, can flexibly control the position of the baffle, realizing the function of blocking or allowing the workpiece to pass, ensuring that the workpiece can be smoothly transported on the conveyor belt. In the initial state, the collar is installed on the fixed shaft and can slide freely. At the same time, the front stop and the rear stop on the collar are located on the front and rear sides of the baffle and keep in contact. When the rear stop contacts the baffle, the baffle will effectively block the workpiece on the conveyor belt, allowing the blade to perform fixed-length cutting. After the cutting task is completed, the blade rotates 180 degrees. This action triggers a series of rotations and movements of the rotating shaft, helical gear plate, transmission belt, transmission wheel, shaft three, gear plate and rack, ultimately This causes the two collars to move away from each other. During this process, although the front stop remains in contact with the front end of the baffle, the rear stop has disengaged from the baffle and no longer forms an obstruction. At this point, the conveyor belt is started, allowing the workpiece to be held against the baffle and tilted, and then the workpiece can pass smoothly, achieving rapid transfer of the workpiece after processing. If the next round of processing is required, the previously rotated 180-degree blade is rotated 90 degrees in the opposite direction, making it perpendicular to the base. This reverse operation also triggers a series of mechanical linkages, causing the rear stop to re-engage with the baffle. Subsequently, the workpiece to be processed is placed on the conveyor belt, and the rear stop will block the workpiece, allowing it to enter the processing flow. It is convenient, fast, practical, and efficient.

[0017] The present invention is further configured such that: the reset mechanism includes a fourth shaft fixedly connected to the bottom of the fixed shaft, the fourth shaft being rotatably connected to the baffle, and torsion springs are sleeved on both sides of the fourth shaft, with the two ends of the torsion springs being fixedly connected to the fourth shaft and the baffle respectively.

[0018] Through the above technical solution, the main function of the reset mechanism is to ensure that the baffle can automatically return to its initial position. After the workpiece is processed, the workpiece will press against the baffle and force it to deflect. During this process, the torsion spring will be compressed. Once the workpiece passes smoothly through the conveyor belt, the baffle loses the squeezing force. At this time, the torsion spring will automatically push the baffle back to its initial state by its elastic force, preparing for the next operation. It is fast and convenient.

[0019] The beneficial effects of this utility model are as follows:

[0020] 1. This utility model uses a fixed-length mechanism to accurately set the cutting length, which is simple to operate and does not rely on the operator's experience, ensuring high cutting accuracy; the design of the transmission mechanism realizes efficient linkage of power transmission, so that the rotation of the rotating shaft can synchronously drive the rotation of the shaft three, which is convenient to operate and highly practical; the opposing mechanism realizes the synchronous opposite or opposite movement of the two racks through the meshing of the gear plate and the rack, which is simple in structure and low in cost, and relies entirely on mechanical transmission without complex control.

[0021] 2. This utility model flexibly controls the position of the baffle plate by cooperating with the collar and the front and rear blocks on the blocking mechanism, thereby blocking or releasing the workpiece and ensuring its smooth transmission on the conveyor belt. The reset mechanism utilizes the elastic force of the torsion spring to automatically reset the baffle plate to its initial state after the workpiece passes, preparing it for the next operation quickly and conveniently. The overall design is simple and practical, highly efficient in operation, has a low failure rate, and is easy to maintain, achieving the functions of high-precision cutting and rapid transmission. Attached Figure Description

[0022] Figure 1 This is a first-view structural diagram of the present invention;

[0023] Figure 2 This is a second-view sectional view of the present invention;

[0024] Figure 3 for Figure 2 A magnified view of a section at point A in the middle;

[0025] Figure 4 for Figure 2 Another sectional view;

[0026] Figure 5 for Figure 4 A magnified view of a section at point B in the middle;

[0027] Figure 6 for Figure 4 A magnified view of a section at point C;

[0028] Figure 7 for Figure 4 Another sectional view;

[0029] Figure 8 for Figure 7 A magnified view of a section at point D.

[0030] In the diagram: 1. Base; 2. Conveyor belt; 3. Rotating shaft; 4. Fixed length mechanism; 401. Sleeve; 402. Protrusion; 403. Bolt; 404. Long rod; 405. Handle; 5. Blade; 6. Fixed shaft; 7. Baffle; 8. Transmission mechanism; 801. Helical gear plate; 802. First support; 803. Second support; 804. Shaft 2; 805. Transmission wheel; 806. Third support; 807. Shaft 3; 808. Transmission belt; 9. Opposing mechanism; 901. Gear plate; 902. Limiting cylinder; 903. Rack; 10. Blocking mechanism; 1001. Collar; 1002. Front stop; 1003. Rear stop; 11. Reset mechanism; 1101. Shaft 4; 1102. Torsion spring. Detailed Implementation

[0031] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the scope of protection of the present invention.

[0032] Please see Figures 1-8This embodiment of a manual fixed-length cutting device includes a base 1, a conveyor belt 2 for conveying the workpiece to be processed is rotatably connected inside the base 1, a rotating shaft 3 is rotatably connected to one side of the base 1, a fixed-length mechanism 4 is slidably connected to the outside of the rotating shaft 3, a blade 5 for cutting the workpiece is fixedly connected to the bottom of the fixed-length mechanism 4, the fixed-length mechanism 4 includes a sleeve 401 slidably connected to the outside of the rotating shaft 3, a protrusion 402 slidably connected to the outside of the rotating shaft 3, a bolt 403 with its front end contacting and abutting the rotating shaft 3 is rotatably connected to the outward side of the sleeve 401, a long rod 404 with its bottom fixedly connected to the blade 5 is fixedly connected to the inward side of the sleeve 401, and a handle 405 is fixedly connected to the other end of the long rod 404. The main function of the fixed-length mechanism 4 is to stabilize the blade 5 and accurately set the required cutting length accordingly. During operation, the desired cutting length can be positioned by sliding the sleeve 401 on the rotating shaft 3 to the desired position. Once the sleeve 401 has slid to the target position, the rotating bolt 403 makes its front end tightly contact the rotating shaft 3, thereby fixing the position of the sleeve 401. When cutting, simply gripping the handle 405 will drive the long rod 404 to deflect, which in turn drives the blade 5 to rotate around the rotating shaft 3, thus realizing the cutting action. At the same time, when the handle 405, long rod 404, and blade 5 deflect, the sleeve 401 deflects, which in turn drives the protrusion 402 to deflect, which in turn drives the rotating shaft 3 to rotate. This process is both fast and convenient, and the design is simple, practical, and low in cost. This mechanism does not rely on the operator's experience and manual precision to ensure high precision in cutting length, and it is easy to adjust, has a low failure rate, and is relatively easy to maintain.

[0033] like Figures 4-6As shown, a fixed shaft 6 is fixedly connected to the top of the base 1, and a baffle 7 for blocking is rotatably connected to the bottom of the fixed shaft 6. A transmission mechanism 8 is fixedly connected to the rear end of the rotating shaft 3. The transmission mechanism 8 includes a helical gear disk 801 fixedly connected to the rear end of the rotating shaft 3. Multiple first brackets 802 are fixedly connected to the top of the base 1. Two first brackets 802 are rotatably connected to the rotating shaft 3, and the other two first brackets 802 are fixedly connected to the fixed shaft 6. A second bracket 803 is fixedly connected to the top of the first bracket 802 located at the rear end of the rotating shaft 3. A shaft 804 is rotatably connected inside the second bracket 803. A helical gear disk 801 is also fixedly connected to the outside of the shaft 804. The two helical gear disks 801 mesh with each other. A transmission wheel 805 is also fixedly connected to the outside of the shaft 804. A third bracket 806 is fixedly connected to the top of the first bracket 802 located on one side of the fixed shaft 6. A shaft rotatably connected to the fixed shaft 6 is rotatably connected inside the third bracket 806. The shaft 3 (shaft 3) is also fixedly connected to a transmission wheel 805. A transmission belt 808 connects the two transmission wheels 805. The function of the transmission mechanism 8 is to use a series of precise mechanical transmissions to make the shaft 3 (shaft 3) rotate. Specifically, when the deflection handle 405 is operated to cause the rotating shaft 3 to rotate, this initial power is transmitted sequentially to the helical gear disk 801, which in turn drives the other helical gear disk 801 to rotate. This rotational kinetic energy is then transmitted to the shaft 2 (shaft 3), and through the linkage of the transmission wheel 805 and the transmission belt 808, it drives the other transmission wheel 805 and finally the shaft 3 (shaft 3) to rotate. This series of smooth mechanical transmission processes ensures that the deflection handle 405 can effectively drive the shaft 3 (shaft 3) to rotate synchronously while driving the rotating shaft 3 to rotate. This design is not only simple to operate, practical and efficient, but also achieves two goals in power transmission, fully demonstrating its ingenuity and practicality.

[0034] like Figures 4-6 As shown, a counter-rotating mechanism 9 is rotatably connected to the top of the fixed shaft 6. The counter-rotating mechanism 9 includes a gear disk 901 fixedly connected to the bottom of the shaft 807. Two first supports 802 located on both sides of the fixed shaft 6 are fixedly connected to the inward side of a limiting cylinder 902. Racks 903, which mesh with the sides of the gear disk 901, are slidably connected inside the two limiting cylinders 902. The two racks 903 are designed to be centrally symmetrical about the gear disk 901. The function of the counter-rotating mechanism 9 is to control the relative movement of the two racks 903 within the limiting cylinders 902. When the shaft 807 rotates, it drives the gear disk 901 to rotate synchronously. This rotation, in turn, causes the two racks 903 to move synchronously towards or away from each other within the limiting cylinders 902. This process is not only convenient to operate and highly practical, but also relies entirely on mechanical transmission, requiring no complex control. Therefore, it has low cost and a simple structure. This design effectively achieves the expected effect through mechanical linkage, making it both economical and efficient.

[0035] like Figures 7-8 As shown, a blocking mechanism 10 is slidably connected to both sides of the fixed shaft 6. The blocking mechanism 10 includes two collars 1001 slidably connected to both sides of the fixed shaft 6. The two collars 1001 are fixedly connected to two racks 903. The front end of each collar 1001 is fixedly connected to a front stop block 1002 that contacts the front end of the baffle 7. The rear end of each collar 1001 is fixedly connected to a rear stop block 1003 that contacts the rear end of the baffle 7. The blocking mechanism 10 can flexibly control the position of the baffle 7 by deflecting the rotating shaft 3, so as to realize the function of blocking or releasing the workpiece and ensure that the workpiece can be smoothly transported on the conveyor belt 2. In the initial state, the collar 1001 is installed on the fixed shaft 6 and can slide freely. At the same time, the front stop block 1002 and the rear stop block 1003 on the collar 1001 are located on the front and rear sides of the baffle 7 and keep in contact. When the rear stop block 1003 contacts the baffle 7, the baffle 7 will effectively block the workpiece on the conveyor belt 2, allowing the blade 5 to perform fixed-length cutting. After the cutting task is completed, the blade 5 rotates 180 degrees. This action triggers a series of rotations and movements of the rotating shaft 3, helical gear disc 801, transmission belt 808, transmission wheel 805, shaft 807, gear disc 901, and rack 903, ultimately causing the two collars 1001 to move away from each other. During this process, although the front stop 1002 remains in contact with the front end of the baffle 7, the rear stop 1003 has disengaged from the baffle 7 and no longer forms an obstruction. At this time, the conveyor belt 2 is started, allowing the workpiece to be held against the baffle 7 and tilted, and then the workpiece can pass smoothly, realizing the rapid transfer of the workpiece after processing. If the next round of processing is required, the blade 5, which has rotated 180 degrees, is rotated 90 degrees in the opposite direction, making it perpendicular to the base 1. This reverse operation also triggers a series of mechanical linkages, causing the rear stop 1003 to re-engage with the baffle 7. Subsequently, the workpiece to be processed is placed on the conveyor belt 2, and the rear stop 1003 will block the workpiece, allowing it to enter the processing flow. It is convenient, fast, practical, and efficient.

[0036] like Figures 7-8 As shown, a reset mechanism 11 is provided at the bottom of the fixed shaft 6. The reset mechanism 11 includes a shaft 1101 fixedly connected to the bottom of the fixed shaft 6. The shaft 1101 is rotatably connected to the baffle 7. Torsion springs 1102 are sleeved on both sides of the shaft 1101. The two ends of the torsion springs 1102 are fixedly connected to the shaft 1101 and the baffle 7, respectively. The main function of the reset mechanism 11 is to ensure that the baffle 7 can automatically return to its initial position. After the workpiece is processed, the workpiece will press against the baffle 7 and force it to deflect. During this process, the torsion spring 1102 will be compressed. Once the workpiece passes smoothly through the conveyor belt 2, the baffle 7 loses the squeezing force. At this time, the torsion spring 1102 automatically pushes the baffle 7 back to its initial state by its elastic force, preparing for the next operation. It is fast and convenient.

[0037] In use, the sleeve 401 on the sliding rotating shaft 3 is moved to the desired position, and the rotating bolt 403 fixes the sleeve 401, setting the cutting length. When the workpiece needs to be cut, the handle 405 is gripped to drive the long rod 404 to deflect upward, causing the blade 5 to rotate upward around the rotating shaft 3. The workpiece is then placed on the transmission belt 808 for transmission until it is blocked by the baffle 7. The blade 5 is then deflected downward to cut the workpiece. After cutting, the handle 405 is rotated 180 degrees. The deflection of the handle 405, long rod 404, and blade 5 causes the sleeve 401 and protrusion 402 to deflect, thereby causing the rotating shaft 3 to rotate. The rotation of the rotating shaft 3 transmits power through the helical gear disc 801, shaft 2 804, transmission wheel 805, and transmission belt 808, ultimately driving shaft 3 807 to rotate. The rotation of shaft 3 807 drives the gear disc 901 to rotate, making... Two racks 903 move synchronously in opposite directions within the limiting sleeve 902; the opposite movement of the racks 903 causes the collars 1001 to slide, causing the two collars 1001 to move away from each other, causing the two rear stops 1003 to disengage from the baffle 7 simultaneously. Then, the transmission belt 808 is activated, causing the processed workpiece to contact the baffle 7, and the workpiece abuts against the baffle 7, causing it to tilt. At this time, the torsion spring 1102 is compressed. After the workpiece passes, the torsion spring 1102 pushes the baffle 7 back to its initial state, ready for the next operation. Then, the blade 5 is rotated 590 degrees in the opposite direction so that the blade 5 is perpendicular to the ground. At the same time, through a series of mechanical transmissions, the rear stops 1003 block the baffle 7 again. The baffle 7 is controlled by the front stops 1002 and the rear stops 1003 to block or release the workpiece. The whole process is simple to operate, practical and efficient, and achieves high-precision cutting and fast transmission.

[0038] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made based on the description and drawings of this utility model, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A manual cut-to-length device comprising a base (1), characterized in that: The base (1) is rotatably connected with a conveying belt (2) for conveying workpieces to be processed, one side of the base (1) is rotatably connected with a rotating shaft (3), the outer part of the rotating shaft (3) is slidably connected with a fixed length mechanism (4), the bottom of the fixed length mechanism (4) is fixedly connected with a blade (5) for cutting workpieces; The top of the base (1) is fixedly connected with a fixed shaft (6), the bottom of the fixed shaft (6) is rotatably connected with a blocking piece (7), the rear end of the rotating shaft (3) is fixedly connected with a transmission mechanism (8), the top end of the fixed shaft (6) is rotatably connected with a facing mechanism (9); The two sides of the fixed shaft (6) are slidably connected with a shielding mechanism (10), and the bottom of the fixed shaft (6) is provided with a reset mechanism (11).

2. A manual cut-to-length apparatus according to claim 1, wherein: The fixed length mechanism (4) comprises a sleeve (401) slidably connected to the outer part of the rotating shaft (3), the outer part of the rotating shaft (3) is fixedly connected with a protrusion (402) slidably connected with the sleeve (401), the outward side of the sleeve (401) is rotatably connected with a bolt (403) having a front end in contact with the rotating shaft (3), the inward side of the sleeve (401) is fixedly connected with a long rod (404) having a bottom fixedly connected with the blade (5), and the other end of the long rod (404) is fixedly connected with a handle (405).

3. A manual cut-to-length apparatus according to claim 1, wherein: The transmission mechanism (8) comprises a helical gear disc (801) fixedly connected to the rear end of the rotating shaft (3), a plurality of first supports (802) are fixedly connected to the top of the base (1), two of the first supports (802) are rotatably connected with the rotating shaft (3), the other two first supports (802) are fixedly connected with the fixed shaft (6), the top of the first support (802) located at the rear end of the rotating shaft (3) is fixedly connected with a second support (803), the second support (803) is rotatably connected with a shaft two (804) inside, the outer part of the shaft two (804) is also fixedly connected with a helical gear disc (801), the two helical gear discs (801) are meshed with each other, the outer part of the shaft two (804) is also fixedly connected with a transmission wheel (805), the top of the first support (802) located at one side of the fixed shaft (6) is fixedly connected with a third support (806), the third support (806) is rotatably connected with a shaft three (807) rotatably connected with the fixed shaft (6) inside, the outer part of the shaft three (807) is also fixedly connected with a transmission wheel (805), and the two transmission wheels (805) are connected with a transmission belt (808).

4. A manual cut-to-length apparatus according to claim 3, wherein: The facing mechanism (9) comprises a gear disc (901) fixedly connected to the outer bottom end of the shaft three (807), two first supports (802) located on the two sides of the fixed shaft (6) are fixedly connected with a limiting cylinder (902) on the inward side, two limiting cylinders (902) are slidably connected with a rack (903) meshed with the two sides of the gear disc (901) respectively, and the two racks (903) are designed to be centrally symmetric with the gear disc (901) as the center.

5. A manual cut-to-length apparatus according to claim 4, wherein: The shielding mechanism (10) includes two collars (1001) slidingly connected on both sides of the fixed shaft (6), the two collars (1001) are fixedly connected with two racks (903) respectively, the front ends of the two collars (1001) are fixedly connected with front stop blocks (1002) in contact with the front ends of the shielding pieces (7), and the rear ends of the two collars (1001) are fixedly connected with rear stop blocks (1003) in contact with the rear ends of the shielding pieces (7).

6. A manual cut-to-length apparatus according to claim 1, wherein: The reset mechanism (11) includes a fourth shaft (1101) fixedly connected at the bottom of the fixed shaft (6), the fourth shaft (1101) is rotatably connected with the shielding piece (7), the two sides of the fourth shaft (1101) are sleeved with torsional springs (1102), and the two ends of the torsional spring (1102) are fixedly connected with the fourth shaft (1101) and the shielding piece (7) respectively.

Images