Tobacco leaf base cutting and severing apparatus and method with adjustable gap clamp conveyor

Abstract

The application discloses a tobacco leaf base cutting and cutting device with adjustable gap clamping conveying and a method, and relates to the technical field of tobacco processing equipment. The device comprises a support frame, a conveying mechanism, an adjustable gap clamping mechanism, a gap adjusting mechanism, a cutting mechanism, a driving mechanism and a control system. The adjustable gap clamping mechanism is arranged directly above the conveying mechanism, and a clamping gap is formed between the two. The clamping mechanism and the conveying mechanism run synchronously and in the same direction to realize flexible clamping and conveying of the tobacco leaf. The gap adjusting mechanism drives the clamping mechanism to ascend and descend through a lead screw and a vertical guide slide rail, thereby realizing accurate stepless adjustment of the clamping gap. The cutting mechanism comprises an upper cutter and a lower cutter, and the two cutters rotate synchronously to cut the tobacco leaf base. The control system is electrically connected with the driving mechanism to regulate and control the running speed of each mechanism. Through the effective combination of adjustable gap flexible clamping, synchronous up-down cutting and intelligent collaborative control, the processing quality and production efficiency of the tobacco leaf base cutting are significantly improved.

Description

Technical Field

[0001] This invention relates to the field of tobacco processing equipment technology, and more specifically to the field of tobacco leaf cutting device and method with adjustable gap clamping and conveying. Background Technology

[0002] In the tobacco re-drying process, stem cutting (i.e., removing the stem base) is a crucial step to ensure homogenization in subsequent processing. The stem base is the hard part at the base of the main vein, and its moisture content and density differ significantly from the main leaf. If it is not effectively removed, it will directly affect the uniformity of moisture content in the re-dried tobacco leaves and the effectiveness of subsequent threshing and winnowing. With the tobacco industry's increasing demands for raw material homogenization, automating and standardizing the stem cutting process has become an urgent industry need.

[0003] Currently, tobacco leaf cutting mainly relies on the following two technical solutions.

[0004] Manual cutting method: This method only includes a simple operating table and a hand-held cutting tool. The edge of the operating table is equipped with positioning strips for aligning the stems. During operation, workers lay the tobacco leaves flat on the table one by one, align them with the positioning strips, and manually cut them with the hand-held tool. The entire process involves no mechanized conveying or clamping, and is a typical intermittent operation, one leaf at a time.

[0005] Simple mechanical tobacco cutting equipment: The existing equipment consists of a fixed frame, conveyor belt, ordinary motor, fixed pressure plate, single cutter mechanism, and cutter drive motor. The conveyor belt is horizontally installed on the frame; the fixed pressure plate is fixed above the conveyor belt by a rigid bracket, forming a fixed, non-adjustable gap between the two; the single cutter is located at the discharge end of the conveyor belt. During operation, the conveyor belt and the cutter are driven at a constant speed by independent motors. The tobacco leaves are conveyed along the conveyor belt, limited by the pressure plate, and then fed to the cutter, where they are cut by the rotating single cutter. The entire machine has no sensors or control systems; each mechanism operates independently.

[0006] The two solutions described above have the following problems due to their respective structural limitations: The drawbacks of manual cutting methods include: extremely low efficiency, intermittent operation cannot match the pace of continuous re-drying production lines; high labor intensity and high labor costs; the cutting position and cutting force are entirely dependent on worker experience, resulting in poor quality consistency and stability; and the cutting process easily pulls on the tobacco leaves, causing breakage and high raw material loss.

[0007] Disadvantages of simple mechanical cutting equipment: (1) The clamping gap is fixed and cannot be adjusted, making it unsuitable for various grades of tobacco leaves. The gap between the pressure plate and the conveyor belt is fixed after manufacturing. When processing thick tobacco leaves, the forced compression causes damage, and when processing thin tobacco leaves, the excessive gap causes slippage and skew, resulting in deviation in the cutting position. This structure cannot meet the flexible processing requirements of tobacco leaves of different thicknesses and grades.

[0008] (2) The single-blade structure leads to poor cutting quality. When the stem base is cut by applying force from only one side, it is easy to cause pulling during cutting, resulting in rough cuts and tearing of the stem base instead of a clean cut, with a high breakage rate; it is particularly inadequate for cutting coarse and hard stem bases.

[0009] (3) There is no coordinated control between conveying and cutting, resulting in low precision. The conveying speed and the cutting speed are both driven by independent motors at fixed speeds, which cannot be adjusted or coordinated, leading to random deviations in the cutting position and poor consistency of the cut.

[0010] (4) Lack of intelligent control capabilities. It has no sensors, no controllers, and no parameter setting and memory functions. It cannot adjust the operating parameters according to the characteristics of raw materials, resulting in poor equipment applicability and low level of automation.

[0011] In summary, existing technologies cannot simultaneously address the issues of clamping adaptability, cutting quality, and intelligent control. Manual solutions are limited by human physiological limitations, while mechanical solutions are constrained by fixed parameters and the structural defects of unidirectional cutting. The root cause lies in the fact that existing technologies cannot achieve flexible adaptation of the clamping gap, force balance during the cutting process, and precise coordinated control of transport and cutting. Therefore, there is an urgent need for a novel cutting solution that integrates adjustable gap flexible clamping, synchronous upper and lower cutting, and intelligent coordinated control. Summary of the Invention

[0012] The purpose of this invention is to solve the technical problems of poor clamping adaptability, low cutting quality and insufficient intelligence level in the prior art. This invention provides a tobacco leaf cutting device and method with adjustable gap clamping and conveying.

[0013] To achieve the above objectives, the present invention specifically adopts the following technical solution: One aspect of the present invention provides a tobacco leaf cutting device with adjustable gap clamping and conveying, comprising: Supporting framework; A conveying mechanism, located at the lower part of the support frame, is used to carry and convey tobacco leaves along a first direction; An adjustable gap clamping mechanism is set on the upper part of the support frame and located directly above the conveying mechanism. An adjustable gap clamping mechanism and the conveying mechanism form a clamping gap for clamping tobacco leaves. The adjustable gap clamping mechanism is configured to run synchronously and in the same direction as the conveying mechanism to form a flexible clamping and conveying of tobacco leaves. The gap adjustment mechanism, connected to the adjustable gap clamping mechanism, is used to drive the adjustable gap clamping mechanism to rise and fall relative to the conveying mechanism in order to adjust the size of the clamping gap. The cutting mechanism is mounted on the support frame and located at the discharge end of the conveying mechanism. The cutting mechanism includes an upper cutter and a lower cutter, which are configured to rotate synchronously to cut the tobacco stem base conveyed to the cutting station. The drive mechanism is used to drive the conveying mechanism, the adjustable gap clamping mechanism, and the cutting mechanism. The control system, electrically connected to the drive mechanism, is used to regulate the conveying speed of the conveying mechanism, the running speed of the adjustable gap clamping mechanism, and the rotational speed of the upper and lower cutters.

[0014] In one embodiment, the adjustable gap clamping mechanism includes a clamping belt, a drive roller, a driven roller, and a sliding support. The drive roller and the driven roller are rotatably mounted on the sliding support. The clamping belt is wrapped around the drive roller and the driven roller. The lower surface of the clamping belt is parallel to the upper surface of the conveying mechanism and forms a clamping gap. The gap adjustment mechanism includes a lead screw and a vertical guide rail. The lead screw is threadedly connected to the sliding support, and the sliding support is slidably engaged with the vertical guide rail. Rotating the lead screw drives the sliding support to rise and fall along the vertical guide rail to achieve precise stepless adjustment of the clamping gap.

[0015] In one embodiment, the conveying mechanism includes a conveyor belt, a drive roller, and a driven roller. The drive roller and the driven roller are rotatably mounted on the lower part of the support frame, and the conveyor belt is wrapped around the drive roller and the driven roller. The driving mechanism includes a first variable frequency motor, a second variable frequency motor, and a reducer. The first variable frequency motor is driven by the drive roller, the second variable frequency motor is driven by the drive roller, and the reducer is driven by the upper cutter and the lower cutter.

[0016] In one embodiment, the upper cutter is mounted on the upper cutter shaft, and the lower cutter is mounted on the lower cutter shaft. The upper and lower cutter shafts are respectively mounted on the discharge end of the support frame via bearing seats. The output end of the reducer is simultaneously connected to the upper and lower cutter shafts via the same transmission chain, so that the upper and lower cutters rotate synchronously in the same direction and at the same speed.

[0017] In one embodiment, the bearing housing is provided with an elongated mounting hole, through which the positions of the upper and lower cutters in the horizontal direction can be finely adjusted to adjust the cutting length.

[0018] In one embodiment, the control system includes a frequency converter, a PLC controller, and a position sensor. The frequency converter is electrically connected to the motors of the drive mechanism and the cutting mechanism, respectively. The position sensor is located at the entrance side of the cutting station and is signal-connected to the PLC controller. The PLC controller controls the cutting action of the cutting mechanism based on the detection signal from the position sensor. The control system also includes a human-machine interface, which is communicatively connected to the PLC controller and is used to set and display operating parameters.

[0019] In one embodiment, the PLC controller has a parameter storage unit for storing process parameter sets corresponding to different tobacco leaf grades. The process parameter sets include clamping gap values, conveying speed values, and cutter rotation speed values.

[0020] In one embodiment, it further includes at least one of the following: a stem base collection hopper disposed below the cutting mechanism, tobacco leaf sorting guide plates disposed on both sides of the feed end of the conveying mechanism, and a safety protective cover disposed outside the cutting mechanism.

[0021] A second aspect of the present invention provides a method for cutting tobacco leaf cutting substrate, comprising the following steps: S1. Parameter preset steps: According to the thickness of the tobacco leaves to be processed and the process requirements, adjust the size of the clamping gap through the gap adjustment mechanism, and set the conveying speed parameters and the cutting speed parameters in the control system. S2. Feeding step: Lay the tobacco leaves flat on the feed end of the conveying mechanism, with the stem base of the tobacco leaves facing the cutting mechanism. S3. Clamping and conveying steps: Start the conveying mechanism and the adjustable gap clamping mechanism to run synchronously in the same direction. The tobacco leaves are clamped in the clamping gap and stably conveyed to the cutting station. S4. Cutting step: The upper and lower cutters rotate synchronously to precisely cut the tobacco stem base that has reached the cutting position in one go. S5. Discharge Steps: The cut tobacco leaves are output through the conveying mechanism, and the cut stems fall and are collected.

[0022] In one embodiment, in step S4, a position sensor located at the entrance of the cutting station detects the tobacco leaf arrival signal, and the control system controls the cutting action of the upper and lower cutters according to the arrival signal; the conveying speed and the cutter speed are controlled in coordination by a frequency converter, and the cutter speed is matched with the conveying speed to ensure a smooth cut.

[0023] The beneficial effects of this invention are as follows: 1. Improved cutting quality and significantly reduced breakage rate: The synchronous upper and lower cutters cut in the same direction, and the tobacco leaves are subjected to force from both the top and bottom during cutting, resulting in a smooth and even cut without roughness, tearing, or pulling. Combined with the adjustable gap flexible clamping conveyor, the tobacco leaves are stably clamped throughout the entire conveying process without slippage or deviation, and are not subjected to excessive compression. The entire process from conveying to cutting effectively reduces tobacco leaf breakage and significantly improves raw material utilization.

[0024] 2. Highly adaptable and widely applicable: The screw adjustment mechanism can continuously and precisely adjust the clamping gap, and together with the vertical guide rail, it ensures that the clamping belt rises and falls smoothly and always remains parallel to the conveyor belt. This allows the equipment to flexibly adapt to tobacco raw materials of different grades, thicknesses, moisture contents, and shapes, meeting the flexible processing needs of multiple types of raw materials and making it a multi-purpose machine.

[0025] 3. Significantly improved production efficiency: The entire process is continuously automated, with the conveyor belt and clamping belt running synchronously and the cutter rotating continuously. The operating speed is infinitely adjustable and can be flexibly matched to different rhythms of the tobacco re-drying production line according to production needs. The operating efficiency is far higher than that of manual cutting, greatly reducing manual input and significantly reducing labor intensity and labor costs.

[0026] 4. High degree of standardization of operation: The entire process is parameterized and controlled. The clamping gap, conveying speed, cutting speed and cutting position can be precisely set, executed and accurately reproduced, completely eliminating the dependence on human experience and ensuring a high degree of consistency in the cutting quality between different operators and different production batches, fully meeting the strict requirements of the cigarette industry for homogenization of raw materials.

[0027] 5. High level of intelligent management and control: It integrates frequency conversion drive and PLC control system, and has the functions of group storage and one-click recall of process parameters, real-time monitoring and display of operating status, and automatic alarm and diagnosis of faults; the human-machine interface is easy to operate and the information is intuitive, while facilitating production quality control and process optimization traceability, and providing data support for intelligent manufacturing. Attached Figure Description

[0028] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of a tobacco leaf cutting device with adjustable gap clamping and conveying.

[0030] Figure 2 yes Figure 1 A side view.

[0031] Figure 3 yes Figure 1 A magnified view of a portion of the image.

[0032] Figure label: 1. Conveying mechanism; 2. Adjustable gap clamping mechanism; 3. Gap adjustment mechanism; 4. Cutting mechanism; 5. Supporting frame; 6. Drive mechanism; 7. Tobacco leaf sorting guide plate; 8. Collection bucket for the rootstock; 9. Safety guard; 21. Sliding support; 22. Clamping strap; 23. Drive roller; 31. Lead screw; 32. Vertical guide rail; 41. Upper cutting blade; 42. Lower cutter. Detailed Implementation

[0033] To make the technical problems, technical solutions, and technical effects of the present invention clearer, 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. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0034] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0035] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0036] In the description of the embodiments of the present invention, it should be noted that the terms "inner", "outer", "upper", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the present invention.

[0037] Example 1 like Figures 1 to 3 As shown, this embodiment provides a tobacco leaf cutting device with adjustable gap clamping and conveying, including a support frame 5, a conveying mechanism 1, an adjustable gap clamping mechanism 2, a gap adjusting mechanism 3, a cutting mechanism 4, a driving mechanism 6, and a control system.

[0038] The support frame 5 serves as the foundational load-bearing structure for the entire device. It is constructed from high-strength steel profiles and possesses sufficient structural rigidity and stability. The support frame 5 has an overall rectangular frame structure, divided into upper and lower sections, with each mechanism installed in its corresponding section.

[0039] The conveying mechanism 1 is located at the lower part of the support frame 5 and is used to carry and convey tobacco leaves in a first direction (i.e., from the feed end to the discharge end). The conveying mechanism 1 includes a conveyor belt, a drive roller, and a driven roller. The drive roller and the driven roller are rotatably mounted at both ends of the lower part of the support frame 5 via bearings, with the drive roller located on the discharge end side and the driven roller located on the feed end side. The conveyor belt is wrapped around the drive roller and the driven roller, forming a closed annular belt drive structure. The upper surface of the conveyor belt is the bearing surface, used to place the tobacco leaves to be processed. The drive roller rotates under the drive mechanism 6, driving the conveyor belt to run through friction, which in turn drives the driven roller to rotate synchronously, realizing the continuous conveying of tobacco leaves.

[0040] The adjustable gap clamping mechanism 2 is located on the upper part of the support frame 5, directly above the conveying mechanism 1. The adjustable gap clamping mechanism 2 includes a clamping belt 22, a drive roller 23, a driven roller, and a sliding support 21. The drive roller 23 and the driven roller are rotatably mounted on both ends of the sliding support 21 via bearings. The clamping belt 22 is wrapped around the drive roller 23 and the driven roller, forming a closed annular belt drive structure. The lower surface of the clamping belt 22 is parallel to the upper surface of the conveyor belt, forming a clamping gap between them for clamping the tobacco leaves. Both the clamping belt 22 and the conveyor belt are made of materials with a certain degree of flexibility and friction coefficient, such as rubber conveyor belts or polyurethane conveyor belts, to ensure flexible clamping of the tobacco leaves without damaging them. The adjustable gap clamping mechanism 2 is configured to run synchronously and in the same direction as the conveying mechanism 1, that is, the running direction of the clamping belt 22 is the same as the running direction of the conveyor belt, and the linear speed is the same, so as to form a flexible clamping and conveying of the tobacco leaves clamped between the two, which not only ensures that the tobacco leaves do not slip or deviate during the conveying process, but also avoids squeezing damage to the tobacco leaves.

[0041] The gap adjustment mechanism 3 is connected to the sliding support 21 of the adjustable gap clamping mechanism 2, and is used to drive the entire adjustable gap clamping mechanism 2 to rise and fall relative to the conveying mechanism 1 to adjust the size of the clamping gap. The gap adjustment mechanism 3 includes a lead screw 31 and a vertical guide rail 32. The lead screw 31 is vertically arranged, with its middle part rotatably mounted on the support frame 5 through a bearing seat, and its upper end is equipped with a handwheel or connected to a drive motor. The lead screw 31 is threadedly connected to the threaded hole provided on the sliding support 21, forming a lead screw and nut transmission pair. The vertical guide rail 32 is fixedly installed on the support frame 5 and extends in the vertical direction. The sliding support 21 is provided with a guide groove or guide block that slides and engages with the vertical guide rail 32. When the lead screw 31 is rotated, the sliding support 21 rises and falls smoothly along the vertical guide rail 32 under the drive of the lead screw and nut pair, thereby driving the entire adjustable gap clamping mechanism 2 to rise and fall, realizing precise stepless adjustment of the clamping gap. The vertical guide rail 32 ensures that the sliding support 21 remains horizontal during the lifting process, and keeps the lower surface of the clamping belt 22 parallel to the upper surface of the conveyor belt, ensuring that the clamping gap is uniform throughout the entire width range.

[0042] The cutting mechanism 4 is mounted on the support frame 5, located at the discharge end of the conveying mechanism 1. The cutting mechanism 4 includes an upper cutter 41 and a lower cutter 42. The upper cutter 41 is mounted on an upper cutter shaft, and the lower cutter 42 is mounted on a lower cutter shaft. The upper and lower cutter shafts are respectively mounted on the discharge end of the support frame 5 via bearing seats, and are arranged vertically opposite each other. Both the upper cutter 41 and the lower cutter 42 are disc-shaped rotating cutters with circumferentially distributed blades. The upper cutter 41 and the lower cutter 42 are configured to rotate synchronously; specifically, they rotate synchronously at the same speed and in the same direction to precisely cut the tobacco stem base conveyed to the cutting station in one pass. When the tobacco stem base enters the interlocking area between the upper cutter 41 and the lower cutter 42, the upper cutter 41 applies a shearing force to the stem base from above and downward, while the lower cutter 42 applies a shearing force to the stem base from below and upward. The two cutters apply shearing forces to the stem base from above and below at the same time, forming a shearing state of force balance, which effectively avoids the pulling and tearing caused by applying force on one side.

[0043] The bearing housing is provided with elongated mounting holes. The positions of the upper cutter 41 and the lower cutter 42 in the horizontal direction can be finely adjusted through the elongated mounting holes. Specifically, after loosening the fixing bolts of the bearing housing, the bearing housing can be moved horizontally to the desired position, and then the fixing bolts can be tightened again, thereby adjusting the horizontal positions of the upper cutter 41 and the lower cutter 42 to adjust the cutting length of the stem base and meet different process requirements.

[0044] The drive mechanism 6 is used to drive the conveying mechanism 1, the adjustable gap clamping mechanism 2, and the cutting mechanism 4. The drive mechanism 6 includes a first variable frequency motor, a second variable frequency motor, and a reducer. The first variable frequency motor is connected to the drive roller of the conveying mechanism 1 via a belt or chain drive, and is used to drive the drive roller to rotate, thereby driving the conveyor belt. The second variable frequency motor is connected to the drive roller 23 of the adjustable gap clamping mechanism 2 via a belt or chain drive, and is used to drive the drive roller 23 to rotate, thereby driving the clamping belt 22. Both the first and second variable frequency motors are variable frequency speed control motors, which can achieve stepless speed regulation through a frequency converter, thereby precisely controlling the running speed of the conveyor belt and the clamping belt 22, and ensuring that they run synchronously and in the same direction.

[0045] The reducer is connected to the upper cutter 41 and lower cutter 42 of the cutting mechanism 4. Specifically, the output end of the reducer is simultaneously connected to both the upper and lower cutter shafts via the same transmission chain. The transmission chain passes over the sprockets on the upper and lower cutter shafts, forming a closed transmission loop. The output power of the reducer is transmitted to both the upper and lower cutter shafts simultaneously via the transmission chain, causing the upper cutter 41 and lower cutter 42 to rotate synchronously at the same speed and in the same direction. Using the same transmission chain to drive both cutter shafts simultaneously ensures the synchronicity of the upper cutter 41 and lower cutter 42, avoiding speed differences and phase deviations that may occur due to independent driving.

[0046] The control system is electrically connected to the drive mechanism 6 and is used to regulate the conveying speed of the conveying mechanism 1, the running speed of the adjustable gap clamping mechanism 2, and the rotational speed of the upper cutter 41 and the lower cutter 42. The control system includes a frequency converter, a PLC controller, and position sensors. The frequency converter is electrically connected to the drive motors of the first and second variable frequency motors of the drive mechanism 6 and the reducer of the cutting mechanism 4, respectively. Stepless speed regulation of each motor is achieved by adjusting the output frequency of the frequency converter. Position sensors are located at the entrance side of the cutting station (i.e., in front of the meshing area of ​​the upper cutter 41 and the lower cutter 42) to detect whether the tobacco leaves have reached the cutting station. Position sensors can be non-contact detection elements such as photoelectric sensors, proximity sensors, or laser sensors. The position sensors are signal-connected to the PLC controller. When the tobacco leaves reach the cutting station, the position sensor generates a detection signal and sends it to the PLC controller. Based on the detection signal from the position sensor, the PLC controller controls the start / stop or speed of the reducer's drive motor via the frequency converter, thereby precisely controlling the timing of the cutting action of the cutting mechanism 4.

[0047] The control system also includes a human-machine interface (such as a touch screen), which communicates with the PLC controller to set and display operating parameters. Operators can input process parameters such as clamping gap, conveying speed, and cutter rotation speed through the human-machine interface, and can also view the equipment's operating status and various parameters in real time.

[0048] The PLC controller has a parameter storage unit that stores process parameter sets corresponding to different tobacco leaf grades. These process parameter sets include clamping gap values, conveyor speed values, and cutter rotation speed values. Operators can access the corresponding process parameter sets through the human-machine interface based on the grade and characteristics of the tobacco leaves to be processed, achieving one-click switching without needing to reset parameters each time, greatly improving production efficiency and parameter consistency.

[0049] The device in this embodiment also includes a stem collection hopper 8 located below the cutting mechanism 4, tobacco leaf sorting guide plates 7 located on both sides of the feed end of the conveying mechanism 1, and a safety cover 9 covering the outside of the cutting mechanism 4. The stem collection hopper 8 is funnel-shaped, wider at the top and narrower at the bottom, and is located directly below the cutting mechanism 4. It is used to collect the cut stems for easy centralized cleaning. The tobacco leaf sorting guide plates 7 are located on both sides of the feed end of the conveying mechanism 1, opening outwards in a V-shape. They guide the tobacco leaves to automatically center themselves when entering the conveyor belt, ensuring the stems face the cutting mechanism 4 for precise subsequent cutting. The safety cover 9, made of a transparent material (such as plexiglass), covers the outside of the cutting mechanism 4. It facilitates observation of the cutting process and effectively prevents operators from accidentally touching the rotating cutter, ensuring operational safety.

[0050] The working principle of this embodiment is explained in detail below: The core working principle of this device can be summarized as a three-in-one system of "adjustable gap flexible clamping, synchronous and balanced cutting from top and bottom, and intelligent and precise control".

[0051] The principle of clamping gap adjustment: Before starting the equipment, the operator needs to adjust the clamping gap according to the thickness and grade of the tobacco leaves to be processed. The thickness of the tobacco leaves varies depending on factors such as grade, origin, and moisture content, and different tobacco leaves require different clamping forces. The operator turns the handwheel to rotate the lead screw 31, and the lead screw 31 and the threaded hole on the sliding support 21 form a lead screw and nut transmission pair. When the lead screw 31 rotates, the sliding support 21 moves along the axial direction (i.e., the vertical direction) of the lead screw 31. During this process, the vertical guide rail 32 guides and constrains the sliding support 21, preventing the sliding support 21 from shifting horizontally or tilting, and ensuring that the sliding support 21 only moves in the vertical direction. Since the clamping belt 22, the drive roller 23, and the driven roller are all mounted on the sliding support 21, the entire adjustable gap clamping mechanism 2 rises and falls synchronously with the sliding support 21. The vertical distance between the lower surface of the clamping belt 22 and the upper surface of the conveyor belt is the clamping gap. This gap value changes continuously with the lifting and lowering of the sliding support 21, achieving stepless adjustment from zero to the maximum stroke range. The vertical guide rail 32 ensures that the clamping belt 22 remains horizontal during the lifting and lowering process, making the clamping gap uniform across the entire width.

[0052] The principle of clamping and conveying tobacco leaves: After the equipment starts, the first variable frequency motor drives the drive roller to rotate via a belt or chain. The drive roller drives the conveyor belt by friction with the conveyor belt. At the same time, the second variable frequency motor drives the drive roller 23 to rotate via a belt or chain. The drive roller 23 drives the clamping belt 22 by friction with the clamping belt 22. The first and second variable frequency motors are driven by the same frequency converter or multiple frequency converters controlled synchronously to ensure precise matching of their speeds, thereby enabling the conveyor belt and the clamping belt 22 to run synchronously at the same linear speed and in the same direction.

[0053] When the tobacco leaves enter the clamping gap between the conveyor belt and the clamping belt 22 from the feed end, the upper surface of the tobacco leaves contacts the lower surface of the clamping belt 22, and the lower surface of the tobacco leaves contacts the upper surface of the conveyor belt. Since the clamping gap is pre-adjusted to be slightly smaller than the natural thickness of the tobacco leaves, the clamping belt 22 and the conveyor belt apply a certain normal clamping force to the tobacco leaves. This clamping force is generated by the elastic deformation of the clamping belt 22 and the conveyor belt, and is a flexible clamping method that will not damage the tobacco leaves. Simultaneously, the friction between the clamping belt 22, the conveyor belt, and the tobacco leaves drives the tobacco leaves forward. Because the linear velocities of the upper and lower belts are the same and in the same direction, the tobacco leaves are driven by pure shear friction during the clamping and conveying process, and will not slip relative to the conveyor belt or the clamping belt 22, thus ensuring that the tobacco leaves reach the cutting station at a constant speed and with an accurate posture.

[0054] The principle of synchronous transection of the stromal base: When the tobacco stem base is conveyed to the cutting station, the position sensor detects the tobacco leaf arrival signal and sends it to the PLC controller. The PLC controller calculates the optimal cutting time according to the preset collaborative control algorithm and precisely controls the drive motor of the reducer through the frequency converter.

[0055] The output of the reducer simultaneously drives the upper and lower cutter shafts to rotate via a transmission chain. Since the sprockets on both the upper and lower cutter shafts have the same meshing relationship with the transmission chain, and the transmission path is the same closed chain, the upper and lower cutter shafts rotate at the same speed and in the same direction. The upper cutter 41 rotates synchronously with the upper cutter shaft, and the lower cutter 42 rotates synchronously with the lower cutter shaft.

[0056] When the tobacco stem base enters the interlocking area between the upper cutter 41 and the lower cutter 42, the blade of the upper cutter 41 cuts into the stem base from top to bottom, and the blade of the lower cutter 42 cuts into the stem base from bottom to top. The cutting positions of the two blades in the thickness direction of the stem base are staggered, but the shearing surfaces overlap. The stem base is subjected to shearing forces in both directions simultaneously. The two shearing forces are opposite in direction but equal in magnitude, forming a pure shear stress state on the stem base cross-section. Compared with the single-sided force cutting method, bidirectional synchronous shearing avoids the bending deformation and tensile tearing of the stem base caused by unilateral force during the cutting process, so that the stem base is cleanly cut in one go under pure shearing action, with a smooth and flat cut.

[0057] The principle of adjusting the cutting length: Cutting length refers to the residual length of the stem base remaining on the main body of the tobacco leaf after the stem base has been removed. By adjusting the horizontal positions of the upper cutter 41 and the lower cutter 42, the position of the cutting station relative to the tobacco leaf conveying direction can be changed, thereby adjusting the cutting length.

[0058] Specifically, after loosening the fixing bolts on the bearing housing, the bearing housing can slide horizontally along the elongated mounting hole. Since the upper and lower cutter shafts are respectively mounted on their corresponding bearing housings, the upper cutter 41 and lower cutter 42 move horizontally synchronously with the bearing housing. When the upper cutter 41 and lower cutter 42 move inward, the remaining length of the cut stem base increases; when the upper cutter 41 and lower cutter 42 move outward, the remaining length of the cut stem base decreases. After adjustment, tightening the fixing bolts will fix the cutting position. The elongated mounting hole provides a continuously adjustable range, allowing the cutting length to be flexibly adjusted according to different tobacco leaf grades and process requirements.

[0059] The principle of coordinated control of conveying and cutting off: The coordinated matching of conveyor speed and cutter rotation speed is crucial to ensuring a smooth cut and consistent cutting position. The PLC controller uses frequency converters to control the drive motors of the first variable frequency motor, the second variable frequency motor, and the reducer, achieving speed coordination among the three.

[0060] Under stable operating conditions, the linear speed v of the conveyor belt, the circumferential linear speed u of the cutter 41 / 42, and the conveying speed of the tobacco leaves remain consistent. The PLC controller calculates the required cutter speed based on the set conveyor speed value and precisely controls the drive motor speed of the reducer through the frequency converter. When the conveyor speed needs to be adjusted due to production cycle time, the PLC controller automatically adjusts the cutter speed synchronously to maintain the matching relationship between the two.

[0061] A position sensor detects the position of the tobacco stem base in real time, and the PLC controller performs closed-loop correction on the cutting timing based on the feedback signal from the position sensor. When there is a deviation between the actual arrival time and the theoretical arrival time of the tobacco stem base, the PLC controller ensures that the cutting action is executed precisely when the stem base reaches the optimal cutting position by fine-tuning the speed of the reducer or delaying / advancing the cutting action.

[0062] The principle of parameter grouping storage and one-click retrieval: The PLC controller's parameter storage unit pre-stores multiple sets of process parameters, each corresponding to a tobacco leaf grade or a processing technology. The process parameter sets include clamping gap values ​​(calibrated by the number of rotations of the lead screw 31 or the feedback value of the displacement sensor), conveying speed values ​​(corresponding to the operating frequencies of the first and second variable frequency motors), and cutter speed values ​​(corresponding to the operating frequency of the reducer drive motor).

[0063] When it is necessary to change the grade of tobacco leaves, the operator selects the corresponding grade through the human-machine interface, and the PLC controller automatically retrieves the corresponding process parameter set. For the clamping gap value, the PLC controller can automatically drive the lead screw 31 to rotate to the target position via a servo motor connected to the lead screw 31, or the operator can be prompted to manually adjust it to the target gap value via the display screen. For the conveyor speed and cutter speed, the PLC controller automatically adjusts each motor to the target speed via a frequency converter. The entire process enables rapid production changeover, eliminating the need for operators to memorize or calculate parameters and avoiding human error.

[0064] Example 2 This embodiment describes a method for cutting tobacco leaf cutting base using the device described in Embodiment 1, comprising the following steps: S1. Parameter Preset Stage: The operator selects the corresponding tobacco grade based on the grade and thickness of the tobacco leaves to be processed through the human-machine interface. The PLC controller retrieves the corresponding process parameter group from the parameter storage unit and displays the target value of the clamping gap, the conveying speed, and the cutting speed on the display screen. Based on the displayed target clamping gap value, the operator rotates the handwheel to rotate the lead screw 31, causing the sliding support 21 to rise and fall along the vertical guide rail 32 to the target position, thus achieving the set clamping gap value. Simultaneously, the PLC controller automatically adjusts the drive motors of the first variable frequency motor, the second variable frequency motor, and the reducer to the target speed via the frequency converter.

[0065] S2, Feeding Stage: The operator lays the tobacco leaves to be processed one by one flat on the feed end of the conveyor belt, with the stem base of the tobacco leaves facing the cutting mechanism 4. When the tobacco leaves enter the conveyor belt, the tobacco leaf sorting guide plates 7 on both sides guide the tobacco leaves to automatically center, ensuring that the tobacco leaves enter the clamping gap in the correct posture.

[0066] S3. Clamping and Conveying Stage: Upon starting the equipment, the first variable frequency motor drives the drive roller 23 to move the conveyor belt, and the second variable frequency motor drives the drive roller 23 to move the clamping belt 22. The conveyor belt and clamping belt 22 move synchronously at the same linear speed and in the same direction. After the tobacco leaves enter the clamping gap, they are flexibly clamped and stably conveyed to the cutting station under the combined action of the conveyor belt and clamping belt 22. Throughout the entire conveying process, the tobacco leaves are flexibly clamped, without slippage, skewness, or compression damage.

[0067] S4. Cutting Stage: When the tobacco stem base is conveyed to the cutting station, the position sensor detects the tobacco stem arrival signal and sends it to the PLC controller. Based on the arrival signal, the PLC controller controls the drive motor of the reducer via the frequency converter, causing the upper cutter 41 and the lower cutter 42 to rotate synchronously. The upper cutter 41 applies shearing force to the tobacco stem base simultaneously from top to bottom and the lower cutter 42 from bottom to top, performing a precise one-time cut of the stem base under pure shearing conditions. The conveying speed and the cutter speed are controlled collaboratively by the frequency converter, ensuring that the cutter speed matches the conveying speed and guarantees a smooth and even cut.

[0068] S5. Discharge and Collection Stage: The cut tobacco leaves continue to be conveyed forward by the conveyor belt and output to the next process. The cut stems fall into the stem collection hopper 8 below the cutting mechanism 4 under gravity and are collected. At this point, the cutting of a single tobacco leaf is completed, and the equipment operates continuously, realizing the continuous automated processing of tobacco leaf cuttings.

Claims

1. A tobacco leaf cutting device with adjustable gap clamping and conveying, characterized in that, include: Supporting framework; A conveying mechanism, located at the lower part of the support frame, is used to carry and convey tobacco leaves along a first direction; An adjustable gap clamping mechanism is disposed on the upper part of the support frame and located directly above the conveying mechanism. An adjustable gap clamping mechanism and the conveying mechanism form a clamping gap for clamping tobacco leaves. The adjustable gap clamping mechanism is configured to operate synchronously and in the same direction as the conveying mechanism to form a flexible clamping and conveying of tobacco leaves. A gap adjustment mechanism, connected to the adjustable gap clamping mechanism, is used to drive the adjustable gap clamping mechanism to move up and down relative to the conveying mechanism to adjust the size of the clamping gap; A cutting mechanism is provided on the support frame and located at the discharge end of the conveying mechanism. The cutting mechanism includes an upper cutter and a lower cutter, which are configured to rotate synchronously to cut the tobacco stem base conveyed to the cutting station. A drive mechanism is used to drive the conveying mechanism, the adjustable gap clamping mechanism, and the cutting mechanism to operate. The control system, electrically connected to the drive mechanism, is used to regulate the conveying speed of the conveying mechanism, the running speed of the adjustable gap clamping mechanism, and the rotational speed of the upper cutter and the lower cutter.

2. The tobacco leaf cutting device with adjustable gap clamping and conveying according to claim 1, characterized in that, The adjustable gap clamping mechanism includes a clamping belt, a drive roller, a driven roller, and a sliding support. The drive roller and the driven roller are rotatably mounted on the sliding support. The clamping belt is wrapped around the drive roller and the driven roller. The lower surface of the clamping belt is parallel to the upper surface of the conveying mechanism and forms the clamping gap. The gap adjustment mechanism includes a lead screw and a vertical guide rail. The lead screw is threadedly connected to the sliding support, and the sliding support is slidably engaged with the vertical guide rail. Rotating the lead screw causes the sliding support to rise and fall along the vertical guide rail, thereby achieving precise stepless adjustment of the clamping gap.

3. The tobacco leaf cutting device with adjustable gap clamping and conveying according to claim 2, characterized in that, The conveying mechanism includes a conveyor belt, a drive roller, and a driven roller. The drive roller and the driven roller are rotatably mounted on the lower part of the support frame, and the conveyor belt is wrapped around the drive roller and the driven roller. The driving mechanism includes a first variable frequency motor, a second variable frequency motor, and a reducer. The first variable frequency motor is driven by the drive roller, the second variable frequency motor is driven by the drive roller, and the reducer is driven by the upper cutter and the lower cutter.

4. The tobacco leaf cutting device with adjustable gap clamping and conveying according to claim 3, characterized in that, The upper cutter is mounted on the upper cutter shaft, and the lower cutter is mounted on the lower cutter shaft. The upper cutter shaft and the lower cutter shaft are respectively mounted on the discharge end of the support frame through bearing seats. The output end of the reducer is simultaneously connected to the upper cutter shaft and the lower cutter shaft through the same transmission chain, so that the upper cutter and the lower cutter rotate synchronously in the same direction and at the same speed.

5. The tobacco leaf cutting device with adjustable gap clamping and conveying according to claim 4, characterized in that, The bearing housing is provided with an elongated mounting hole, through which the positions of the upper cutter and the lower cutter in the horizontal direction can be finely adjusted to adjust the cutting length.

6. The tobacco leaf cutting device with adjustable gap clamping and conveying according to any one of claims 1-5, characterized in that, The control system includes a frequency converter, a PLC controller, and a position sensor. The frequency converter is electrically connected to the motors of the drive mechanism and the cutting mechanism, respectively. The position sensor is located at the entrance side of the cutting station and is signal-connected to the PLC controller. The PLC controller controls the cutting action of the cutting mechanism based on the detection signal from the position sensor. The control system also includes a human-machine interface, which is communicatively connected to the PLC controller and is used to set and display operating parameters.

7. The tobacco leaf cutting device with adjustable gap clamping and conveying according to claim 6, characterized in that, The PLC controller has a parameter storage unit, which is used to store process parameter sets corresponding to different tobacco leaf grades. The process parameter sets include clamping gap value, conveying speed value, and cutting speed value.

8. The tobacco leaf cutting device with adjustable gap clamping and conveying according to any one of claims 1-5, characterized in that, It also includes at least one of the following: a stem collection hopper located below the cutting mechanism, tobacco leaf sorting guide plates located on both sides of the feed end of the conveying mechanism, and a safety guard covering the outside of the cutting mechanism.

9. A method for cutting tobacco leaf cutting base using the apparatus described in any one of claims 1-8, characterized in that, Includes the following steps: S1. Parameter preset step: According to the thickness of the tobacco leaves to be processed and the process requirements, the size of the clamping gap is adjusted by the gap adjustment mechanism, and the conveying speed parameter and the cutting speed parameter are set in the control system. S2. Feeding step: Lay the tobacco leaves flat on the feed end of the conveying mechanism, with the stem base of the tobacco leaves facing the cutting mechanism. S3. Clamping and conveying step: Start the conveying mechanism and the adjustable gap clamping mechanism to run synchronously and in the same direction. The tobacco leaves are clamped in the clamping gap and stably conveyed to the cutting station. S4. Cutting step: The upper cutter and the lower cutter rotate synchronously to cut the tobacco stem base that has reached the cutting position in one precise cut. S5. Discharge step: The cut tobacco leaves are output through the conveying mechanism, and the cut stems fall and are collected.

10. The method for cutting tobacco leaf cutting base according to claim 9, characterized in that, In step S4, a position sensor located at the entrance of the cutting station detects the tobacco leaf arrival signal, and the control system controls the cutting action of the upper and lower cutters according to the arrival signal; the conveying speed and the cutting speed are controlled in coordination by a frequency converter, and the cutting speed is matched with the conveying speed to ensure a smooth cut.

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