Reducing and pitch-changing bent tooth pre-cutting threshing cylinder for small area

Abstract

The invention discloses a variable-diameter variable-pitch bent-tooth pre-cutting threshing cylinder for a small area, and belongs to the technical field of agricultural machinery, the variable-diameter variable-pitch bent-tooth pre-cutting threshing cylinder comprises a cylinder main body, the cylinder main body is composed of a hollow cylinder, an integrated double-air-duct fan, two transmission assemblies and a variable-diameter regulation and control mechanism, and the two ends of the hollow cylinder are connected with the transmission assemblies through mounting grooves; the hollow roller is internally and rotatably connected with an integrated double-air-duct fan, the hollow roller is connected with a variable-diameter regulation and control mechanism through a transmission assembly and the integrated double-air-duct fan, a plurality of plate tooth spacing adjustment mechanisms are fixedly arranged on the side, away from the axis, of the variable-diameter regulation and control mechanism, and a plurality of bent plate teeth are arranged on the plate tooth spacing adjustment mechanisms; the device is provided with the variable-diameter regulation and control mechanism and the plate tooth spacing adjustment mechanism, the spacing of bent plate teeth and the diameter range of the hollow roller can be adjusted, and accurate matching of the working diameter of the hollow roller and the crop space structure is achieved according to plant spacing and line spacing changes of crops in different plots.

Description

Technical Field

[0001] This invention belongs to the field of agricultural machinery technology, specifically relating to a small-diameter, variable-pitch curved-tooth threshing drum before cutting. Background Technology

[0002] Traditional rice combine harvesters use a "cut first, thresh later" method, which suffers from significant grain loss and machine clogging caused by damp straw. To overcome this bottleneck, many countries have explored "pre-harvest threshing" technology since the 20th century. The core of pre-harvest threshing technology lies in the threshing element operating in situ on the upright rice plants in the field, directly detaching the grains from the ear. Subsequently, the resulting mixture (containing grains, broken stems and leaves, husks, etc.) undergoes secondary threshing, separation, and cleaning to ultimately obtain clean grains.

[0003] Existing pre-harvest threshing drum devices generally suffer from the following limitations in structural design: the radial spacing between the threshing actuators—the teeth—is usually a fixed value, lacking adjustment capability, and mostly employs a traditional flat tooth structure. This type of structure is poorly adaptable to multi-variety breeding and harvesting operations in small plots, failing to meet the diverse needs of different crop varieties in terms of plant and row spacing. Due to the limitations of the tooth surface morphology, the contact area between the flat teeth and the crop ears is small, making it difficult to effectively remove kernels from the ears. This results in some kernels remaining on the cob, increasing unsorted losses. Therefore, how to provide a pre-harvest threshing drum with variable diameter and spacing curved teeth for small plots is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0004] The main objective of this invention is to provide a variable-diameter, variable-spacing curved-tooth pre-harvesting threshing drum for different plots, thereby solving the aforementioned technical problems. This device is equipped with a variable-diameter control mechanism and a tooth spacing adjustment mechanism, enabling adjustment of the spacing of the curved teeth and the diameter range of the hollow drum. Based on variations in plant spacing and row spacing in different plots, it achieves precise matching between the working diameter of the hollow drum and the spatial structure of the crop, effectively overcoming the problems of poor adaptability and insufficient grain threshing in heterogeneous breeding plots caused by single-diameter drums.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A variable-diameter, variable-pitch, curved-tooth threshing drum for pre-cutting in a small-area production area includes a drum body, which is composed of a hollow drum, an integrated dual-duct fan, two transmission components, and a variable-diameter control mechanism. Both ends of the hollow drum are connected to the transmission components via mounting slots located between the hollow drum and the variable-diameter control mechanism. The integrated dual-duct fan is rotatably connected inside the hollow drum. The hollow drum is connected to the variable-diameter control mechanism via the transmission components and the integrated dual-duct fan. Multiple tooth spacing adjustment mechanisms are fixedly installed on the side of the variable-diameter control mechanism away from the axis, and multiple curved teeth are provided on each tooth spacing adjustment mechanism.

[0007] Furthermore, the transmission component includes a small gear and a large gear, both of which are disposed within a mounting groove. A gear connecting hole is provided at the center of each gear. A rotating shaft is fixedly connected to the gear connecting hole of the small gear. A connecting shaft is provided inside the hollow roller. Both ends of the connecting shaft pass through both ends of the hollow roller and are connected to one end of the rotating shaft on the small gear. The other end of the rotating shaft is rotatably connected to a diameter adjustment mechanism. The large gear is connected to an integrated dual-duct fan through the gear connecting hole. The large gear and the small gear mesh with each other. The large gear has multiple arc-shaped sliding grooves, each containing a slidably connected cylindrical pin. The cylindrical pins are connected to the diameter adjustment mechanism. The small gear at one end of the hollow roller is connected to the output end of a gear drive motor through a rotating shaft. The gear drive motor is fixed to the diameter adjustment mechanism.

[0008] Furthermore, the variable diameter control mechanism includes two covers, multiple arc-shaped plates, and support rods. The two covers are detachably connected to both ends of the hollow roller. The multiple arc-shaped plates are arranged around the circumference of the hollow roller. The side of each arc-shaped plate near the center is fixedly connected to two support rods. The ends of the two support rods away from the arc-shaped plates pass through the sides of the two covers and are connected to cylindrical pins. A gear drive motor is also fixedly connected to the inner wall of the cover.

[0009] Furthermore, the tooth spacing adjustment mechanism includes a support frame fixed on the diameter adjustment mechanism. Multiple guide shafts and a contour cam are arranged between the support frames. Both ends of the guide shafts are fixedly connected to the support frames. A synchronous motor is fixedly mounted on the support frame. The output end of the synchronous motor passes through the support frame and is connected to one end of the contour cam. The other end of the contour cam is rotatably connected to the support frame. Multiple sliders are slidably connected to the guide shafts and the contour cam. Guide pins are connected to the sliders. A guide groove is provided on the contour cam. The end of the guide pin away from the slider is slidably connected to the guide groove. A bent tooth can also be detachably connected to the slider.

[0010] Furthermore, an integrated dual-duct fan is also installed inside the hollow drum. One end of the integrated dual-duct fan is provided with an air inlet pipe and an air outlet pipe, and the other end is provided with a fan shaft. The fan shaft extends axially through the hollow drum, the diameter adjustment mechanism, and the gear connection hole of the large gear at the same end, extending to the outside. The air inlet pipe and the air outlet pipe extend axially through the hollow drum, the diameter adjustment mechanism, and the gear connection hole of the large gear at the same end, extending to the outside. Roller bearings are provided at the contact points between the fan shaft and the hollow drum, the diameter adjustment mechanism, and the gear connection hole of the large gear. Roller bearings are also provided at the contact points between the air inlet pipe and the air outlet pipe and the gear connection hole of the hollow drum, the diameter adjustment mechanism, and the large gear. The integrated dual-duct fan is also provided with multiple air outlets and exhaust ports.

[0011] Compared with the prior art, the present invention has the following beneficial effects:

[0012] This invention is equipped with a diameter adjustment mechanism and a tooth spacing adjustment mechanism, which can adjust the spacing of the curved tooth and the diameter range of the hollow roller. According to the plant spacing and row spacing of crops in different plots, the working diameter of the hollow roller can be accurately matched with the spatial structure of the crop, effectively overcoming the problems of poor adaptability and insufficient grain shedding of single-diameter rollers in heterogeneous breeding plots.

[0013] The variable diameter control mechanism is equipped with a transmission component, and the tooth spacing adjustment mechanism is equipped with a contour cam with a guide groove. The transmission component and the contour cam can achieve a high degree of synergistic optimization of the overall structure and function of the device. The gap between the curved teeth is adjusted by the contour trajectory of the guide groove on the contour cam, which enhances the coupling contact ability between the teeth and the crop and improves the threshing effect.

[0014] The curved tooth design further expands the crop contact area and induces stronger airflow disturbance during operation, forming a stable turbulent field and generating beneficial disturbance force during grain stripping, which is significantly better than the traditional planar tooth structure.

[0015] In addition, the dual-duct fan system nested inside the hollow drum, including the suction and blowing ducts, can generate an intake airflow before the crop enters the threshing area to enhance the grain input efficiency, and generate a blowing airflow after threshing to assist in grain transport. Together with the disturbance effect of the bending plate teeth, it reduces grain re-carrying and residue rate, thereby significantly improving the overall harvesting performance and adaptability of the machine. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the structure of the present invention.

[0018] Figure 2 This is an exploded structural diagram of the hollowed-out roller and the diameter adjustment mechanism.

[0019] Figure 3 This is a side view of the variable diameter control mechanism.

[0020] Figure 4 A schematic diagram of the structure after the hollowed-out roller and the diameter adjustment mechanism are installed.

[0021] Figure 5 This is a schematic diagram of the plate tooth spacing adjustment mechanism.

[0022] Figure 6 This is a schematic diagram of the slider's structure.

[0023] Figure 7 This is a schematic diagram of the structure of an integrated dual-duct fan.

[0024] Figure 8 This is a schematic diagram of the profile cam.

[0025] Figure 9 This is a schematic diagram of the connection structure between the integrated dual-duct fan, the hollowed-out roller, and the diameter adjustment mechanism.

[0026] Among them, 1-roller body, 2-synchronous motor, 3-plate tooth spacing adjustment mechanism, 4-fan shaft, 5-roller bearing, 6-bent plate tooth, 7-integrated dual-duct fan, 8-hollowed-out roller, 9-diameter adjustment mechanism, 10-support rod, 11-large gear, 12-small gear, 13-cylindrical pin, 14-connecting shaft, 15-contour cam, 16-slider, 17-guide pin, 18-inlet pipe, 19-outlet pipe, 20-air outlet, 21-exhaust port. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] like Figures 1-9 As shown, this invention provides a variable diameter, variable pitch, curved tooth pre-threshing drum for small-scale crops, comprising a drum body 1. The drum body 1 consists of a hollow drum 8, an integrated dual-duct fan 7, two transmission components, and a variable diameter control mechanism 9. Both ends of the hollow drum 8 are connected to transmission components via mounting slots located between the hollow drum 8 and the variable diameter control mechanism 9. The integrated dual-duct fan 7 is rotatably connected inside the hollow drum 8. The hollow drum 8 is connected to the variable diameter control mechanism 9 via the transmission components and the integrated dual-duct fan 7. Multiple tooth spacing adjustment mechanisms 3 are fixedly installed on the side of the variable diameter control mechanism 9 away from the axis. Multiple curved teeth 6 are provided on the tooth spacing adjustment mechanisms 3. The variable diameter control mechanism 9 can change the diameter of the drum body 1, facilitating its use on different crops; the tooth spacing adjustment mechanisms 3 can adjust the spacing between the curved teeth 6, ensuring cutting effectiveness during cutting.

[0029] In this embodiment, the transmission component includes a small gear 12 and a large gear 11. Both the small gear 12 and the large gear 11 are disposed in the mounting groove. A gear connecting hole is provided at the center of both the small gear 12 and the large gear 11. A rotating shaft is fixedly connected in the gear connecting hole of the small gear. A connecting shaft 14 is provided inside the hollow roller 8. The two ends of the connecting shaft 14 pass through the two ends of the hollow roller 8 and are connected to one end of the rotating shaft on the small gear 12. The other end of the rotating shaft is rotatably connected to the diameter adjustment mechanism 9. The large gear 11 is connected to the integrated dual-duct fan 7 through the gear connecting hole. The large gear 11 and the small gear 12 mesh with each other. Multiple arc-shaped sliding grooves are provided on the large gear 11. A cylindrical pin 13 is slidably connected in each arc-shaped sliding groove. The cylindrical pin 13 is connected to the diameter adjustment mechanism 9. The small gear 12 at one end of the hollow roller 8 is connected to the output end of the gear drive motor through the rotating shaft. The gear drive motor is fixed on the diameter adjustment mechanism 9. The connecting shaft 14 connecting the two pinions 12 ensures that the two pinions 12 can rotate synchronously; in addition, when the pinion 12 rotates, it can drive the large gear 11 to rotate, and use the movement of the arc-shaped slide to push the cylindrical pin and the diameter adjustment mechanism 9 to move and change the diameter.

[0030] In this embodiment, the diameter adjustment mechanism 9 includes two covers, multiple arc-shaped plates, and support rods 10. The two covers are detachably connected to both ends of the hollow roller 8. The multiple arc-shaped plates are arranged around the circumference of the hollow roller 8. The side of each arc-shaped plate near the center is fixedly connected to the two support rods 10. The ends of the two support rods 10 away from the arc-shaped plates pass through the sides of the two covers and are connected to cylindrical pins 13. A gear drive motor is also fixedly connected to the inner wall of the covers. When the large gear 22 drives the arc-shaped groove to rotate, the cylindrical pins 13 are pushed by the arc-shaped groove, thereby pushing the support rods 10 to move telescopically, causing the distance between the arc-shaped plates and the axis of the hollow roller 8 to change, thus realizing the change of the diameter of the roller body 1.

[0031] In this embodiment, the tooth spacing adjustment mechanism 3 includes a support frame fixed on the diameter adjustment mechanism 9. Multiple guide shafts and a contour cam 15 are arranged between the support frames. Both ends of the guide shafts are fixedly connected to the support frames. A synchronous motor 2 is fixedly mounted on the support frame. The output end of the synchronous motor 2 passes through the support frame and is connected to one end of the contour cam 15. The other end of the contour cam 15 is rotatably connected to the support frame. Multiple sliders 16 are slidably connected to the guide shafts and the contour cam 15. Guide pins 17 are connected to the sliders 16. A guide groove is provided on the contour cam 15. The end of the guide pin 17 away from the slider 16 is slidably connected to the guide groove. Curved teeth 6 can also be detachably connected to the sliders 16. Due to its special curved surface structure, the curved teeth 6 disrupt airflow stability during contact with the crop, thus forming strong turbulence inside the drum body 1. This turbulence enhances the disturbance effect between the grains and the curved teeth 6, improving threshing efficiency, helping to completely separate the grains from the ears, and to a certain extent promoting the conveying of grains towards the discharge direction, reducing residue and backflow.

[0032] In this embodiment, an integrated dual-duct fan 7 is also provided inside the hollow drum 8. One end of the integrated dual-duct fan 7 is provided with an air inlet pipe 18 and an air outlet pipe 19, and the other end of the integrated dual-duct fan 7 is provided with a fan shaft 14. The fan shaft 14 extends axially through the gear connection holes of the hollow drum 8, the diameter adjustment mechanism 9, and the large gear 11 at the same end. The air inlet pipe 18 and the air outlet pipe 19 extend axially through the gear connection holes of the hollow drum 8, the diameter adjustment mechanism 9, and the large gear 11 at the same end. Roller bearings 5 ​​are provided at the contact points between the fan shaft 14 and the gear connection holes of the hollow drum 8, the diameter adjustment mechanism 9, and the large gear 11. Roller bearings 5 ​​are also provided at the contact points between the air inlet pipe 18 and the air outlet pipe 19 and the gear connection holes of the hollow drum 8, the diameter adjustment mechanism 9, and the large gear 11. The integrated dual-duct fan 7 is also provided with multiple air outlets 20 and exhaust ports 21. The exhaust duct connected to the blower creates a directional negative pressure airflow before the crop enters the comb tooth area, guiding the crop to make fuller contact with the curved tooth area and improving the initial threshing efficiency. After threshing, the blower connected to the blower applies a positive pressure airflow to push the grains to be quickly transported to the output channel. In coordination with the rotation direction of the drum, this effectively reduces the risk of grain residue and backflow.

[0033] Working principle: During operation, the diameter of the drum body 1 is adjusted by the diameter adjustment mechanism 9, and the spacing between the bent teeth 6 is adjusted by the inner tooth spacing adjustment mechanism 3. The entire drum device is rigidly connected to the output end of the output motor on the harvester through the flange, ensuring stable positioning of the device during operation. The drum body 1 is powered by the output motor on the harvester, which drives the drum body 1 to rotate and provides the energy input for each adjustment mechanism.

[0034] The variable diameter adjustment mechanism 9 integrated at the top of the hollow roller 8 drives the small gear 12 to rotate via a gear-driven motor, which in turn drives the large gear 11 at the center to rotate. During rotation, multiple arc-shaped grooves on the large gear 11 guide the support rods in the grooves to move radially through the cylindrical pins 13, thereby achieving dynamic adjustment of the outer diameter of the roller body 1. This adjustment process is mainly used to adapt to differences in crop spacing, row spacing, and ear size in different plots, enabling the roller structure to respond quickly to the spatial distribution of crops, thereby improving crop combing adaptability and operational efficiency.

[0035] During operation, the tooth spacing adjustment mechanism 3 drives the contour cam 15 to rotate via multiple synchronous motors. The contour cam 15 has continuous and equidistant contour trajectory guide grooves on its surface, which can form a sliding engagement with the guide pin 17 on the slider 16. As the contour cam 15 rotates, the slider 16 reciprocates linearly along its guide groove path, thereby causing the curved teeth 6 to move synchronously in the axial direction, achieving dynamic adjustment of the tooth spacing. This adjustment process aims to optimize the threshing contact area by adjusting the tooth arrangement density and contact intensity according to the physical characteristics of different crop varieties or maturity stages, such as grain density, ear hardness, and threshing sensitivity.

[0036] During operation, as the main body of the drum 1 continues to rotate, the curved plate teeth 6 installed on it move at high speed. The device also integrates an integrated dual-duct fan 7, which is fixedly installed at a certain angle in the internal cavity of the hollow drum 8. The relative rotation connection between the drum bearing 5 and the hollow drum 8 is achieved. The cooperation between the curved plate teeth 6 and the integrated dual-duct fan 7 results in higher overall threshing efficiency and better threshing effect, which can reduce the risk of grain residue and re-carrying.

[0037] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0038] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A variable diameter, variable pitch curved tooth threshing drum for pre-cutting in a small-area production area, characterized in that, The device includes a drum body (1), which consists of a hollow drum (8), an integrated dual-duct fan (7), two transmission components, and a diameter adjustment mechanism (9). Both ends of the hollow drum (8) are connected to the transmission components through mounting slots. The mounting slots are located between the hollow drum (8) and the diameter adjustment mechanism (9). The hollow drum (8) is rotatably connected to the integrated dual-duct fan (7). The hollow drum (8) is connected to the diameter adjustment mechanism (9) through the transmission components and the integrated dual-duct fan (7). Multiple tooth spacing adjustment mechanisms (3) are fixedly installed on the side of the diameter adjustment mechanism (9) away from the axis. Multiple curved teeth (6) are provided on the tooth spacing adjustment mechanism (3).

2. The pre-threshing drum for variable diameter and variable pitch curved teeth cutting according to claim 1, characterized in that, The transmission assembly includes a pinion (12) and a large gear (11), both of which are mounted in a mounting groove. A gear connecting hole is provided at the center of each of the pinion (12) and the large gear (11). A rotating shaft is fixedly connected to the gear connecting hole of the pinion. A connecting shaft (14) is provided inside the hollow roller (8). Both ends of the connecting shaft (14) pass through both ends of the hollow roller (8) and are connected to one end of the rotating shaft on the pinion (12). The other end of the rotating shaft is connected to a diameter adjustment mechanism. (9) Rotary connection, the large gear (11) is connected to the integrated dual-duct fan (7) through the gear connection hole, the large gear (11) and the small gear (12) mesh with each other, the large gear (11) is provided with multiple arc-shaped sliding grooves, and cylindrical pins (13) are slidably connected in each arc-shaped sliding groove. The cylindrical pins (13) are connected to the diameter adjustment mechanism (9), and the small gear (12) at one end of the hollow roller (8) is connected to the output end of the gear drive motor through the rotating shaft. The gear drive motor is fixed on the diameter adjustment mechanism (9).

3. A pre-threshing drum with variable diameter and pitch curved teeth according to claim 2, characterized in that, The variable diameter control mechanism (9) includes two covers, multiple arc plates, and support rods (10). The two covers are detachably connected to both ends of the hollow roller (8). The multiple arc plates are arranged around the circumference of the hollow roller (8). The side of each arc plate near the center is fixedly connected to the two support rods (10). The ends of the two support rods (10) away from the arc plates pass through the sides of the two covers and are connected to the cylindrical pins (13). A gear drive motor is also fixedly connected to the inner wall of the cover.

4. A pre-threshing drum with variable diameter and pitch curved teeth as described in claim 2, characterized in that, The tooth spacing adjustment mechanism (3) includes a support frame fixed on the variable diameter control mechanism (9). Multiple guide shafts and a profile cam (15) are provided between the support frames. Both ends of the guide shafts are fixedly connected to the support frames. A synchronous motor (2) is fixedly provided on the support frame. The output end of the synchronous motor (2) passes through the support frame and is connected to one end of the profile cam (15). The other end of the profile cam (15) is rotatably connected to the support frame. Multiple sliders (16) are slidably connected to the guide shafts and the profile cam (15). A guide pin (17) is connected to the slider (16). A guide groove is provided on the profile cam (15). The end of the guide pin (17) away from the slider (16) is slidably connected to the guide groove. A bent tooth (6) can also be detachably connected to the slider (16).

5. A pre-threshing drum with variable diameter and pitch curved teeth according to claim 2, characterized in that, The hollow drum (8) is also equipped with an integrated dual-duct fan (7). One end of the integrated dual-duct fan (7) is provided with an air inlet pipe (18) and an air outlet pipe (19). The other end of the integrated dual-duct fan (7) is provided with a fan shaft (14). The fan shaft (14) extends axially through the hollow drum (8), the diameter adjustment mechanism (9), and the gear connection hole of the large gear (11) at the same end. The air inlet pipe (18) and the air outlet pipe (19) extend axially through the hollow drum (8), the diameter adjustment mechanism (9), and the gear connection hole of the large gear (11) at the same end. The gear connection holes of the control mechanism (9) and the large gear (11) extend to the outside. The fan shaft (14) is provided with roller bearings (5) at the contact points of the hollow roller (8), the diameter control mechanism (9) and the large gear (11). The air inlet pipe (18) and the air outlet pipe (19) are provided with roller bearings (5) at the contact points of the hollow roller (8), the diameter control mechanism (9) and the large gear (11). The integrated dual-duct fan (7) is also provided with multiple air outlets (20) and exhaust ports (21).

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