A threshing system having a reverse screening cylinder

Abstract

The application discloses a threshing system with a reverse screening roller, which comprises a cylindrical screening roller and a threshing roller arranged concentrically with the screening roller; the threshing roller is connected with a power source; the rotation direction of the threshing roller is opposite to that of the screening roller; the application further comprises a transition shaft, which is connected with the central shaft of the threshing roller through a same-direction transmission component; the transition shaft is fixed with a first gear, and the screening roller is fixed with a second gear; the first gear is directly engaged with the second gear. The transmission system composed of the transition shaft, the same-direction transmission component and the gear set establishes the transmission relationship between the threshing roller and the screening roller, so that the threshing roller and the screening roller rotate reversely; the screening roller does not need an additional power source to drive the operation, the cost can be reduced, the rotation speed of the screening roller can be always adapted to the speed of the threshing roller, and in addition, the transmission system can play a role in speed reduction, so that the rotation speed of the screening roller is far less than that of the threshing roller.

Description

Technical Field

[0001] The invention relates to the technical field of crop threshing, in particular to a threshing system with a reverse screening drum. Background Art

[0002] When a combine harvester harvests crops such as rice, wheat, and rapeseed, it needs to thresh the crops at the same time. A threshing device is integrated in the harvester. For example, the mainstream threshing device provided by patent CN202019562U includes a concave screen, a guide assembly, and a threshing drum. The guide assembly includes a grass guide plate. When this threshing device is working, the crops are rubbed by the threshing drum and the concave screen, so that the grains are separated from the straw and fall from the sieve holes. When this device is operated for a long time, the sieve holes of the concave screen are easily blocked, affecting the discharge of the grains. The sieve holes need to be cleaned more frequently, and the separation area of ​​the concave screen is limited. The crops cannot be separated in time, resulting in multiple blows, the material is finely broken, and the amount of material on the screen surface is large, which increases the difficulty of cleaning in the subsequent cleaning link. In order to solve the above problems, the applicant's prior application CN114631432A discloses a full-angle threshing and separation device and a threshing method, which includes a 360° rotary concave screen that rotates in the opposite direction to the threshing drum. When in use, the threshing drum is connected to a power source, and the concave screen is driven by a transmission device connected to another power source. The transmission device includes a right-angle commutator, a chain, a bolt, and a driving wheel. The chain is installed in the center of the concave screen and arranged around the concave screen. In actual use, this structure has a high failure rate and is easily affected by materials and stuck. It also requires two power sources, which is more expensive. The single-point drive has a large and unstable resistance to the reversing drum speed, and the structural strength is also poor. In addition, it is necessary to coordinate the speeds of the threshing drum and the concave screen, and the control also requires additional costs. Summary of the Invention

[0003] Purpose of the invention: In order to overcome the deficiencies in the prior art, the present invention provides a threshing system with a reversing screening drum, which has a simple structure, high stability, good reliability, low cost and can adapt the rotation speed of the screening drum to the threshing drum.

[0004] Technical solution: To achieve the above-mentioned object, the present invention provides a threshing system with a reverse screening drum, which comprises a cylindrical screening drum and a threshing drum arranged concentrically with the screening drum; the threshing drum is connected to a power source, which can be a rotational torque directly or indirectly transmitted from a motor or an engine; the rotation direction of the threshing drum is opposite to that of the screening drum;

[0005] It also includes a transition shaft, and a transmission relationship is established between the transition shaft and the central shaft of the threshing drum through a same-direction transmission component, so that the transition shaft and the central shaft rotate in the same direction; a first gear is fixed on the transition shaft, and a second gear is fixed on the screening drum, and the first gear is directly meshed with the second gear.

[0006] Furthermore, the same-direction transmission component includes a first sprocket fixed on the central shaft and a second sprocket fixed on the transition shaft; power is transmitted between the first sprocket and the second sprocket via a chain.

[0007] Furthermore, the second gear is fixed to both ends of the screening drum, and the first gear is fixed to both ends of the transition shaft, and the first gear is meshed with the second gear in a one-to-one correspondence.

[0008] Furthermore, both ends of the screening drum have rolling flanges; the threshing system also includes a rolling guide frame arranged corresponding to each rolling flange, and the rolling guide frame includes a frame body and a plurality of rollers rotatably mounted relative to the frame body and arranged along a circular arc path. The frame body is composed of two circular arc plates, and all rollers are placed between the two circular arc plates. The rolling flange contacts all rollers in the corresponding rolling guide frame. The roller is a groove wheel with an annular groove in the middle, so that the rolling flange can be kept from contacting the circular arc plate body. The rolling flange located at the same end of the screening drum is installed adjacent to the second gear.

[0009] The central shaft is located laterally of the central axis, i.e., adjacent to the left or right quadrant of the screening drum. Therefore, the meshing position of the first and second gears avoids the concentrated point of material movement, thus preventing material from entering between the first and second gears. This is achieved due to the simple and compact design of the transmission system of the present invention.

[0010] Furthermore, a cover is provided above the screening drum. The projection of the cover in the axial direction of the screening drum is narrow at the top and wide at the bottom. In this embodiment, the axial projection is a trapezoid. By providing the cover, the grains thrown out from the upper screen of the screening drum can be blocked by the cover, preventing the grains from scattering and preventing grain loss.

[0011] Furthermore, multiple sets of grass guide assemblies are mounted on the inner wall of the screening drum. Each set of grass guide assemblies includes multiple parallel grass guide plates, with the ends of the grass guide plates staggered axially along the screening drum. As the screening drum rotates, the material passes through the grass guide plates, which act on the material to cause axial movement relative to the screening drum, causing it to move forward along the screening drum. After cleaning, impurities are discharged from the end of the screening drum.

[0012] Furthermore, the inclination angle of the grass guide plate relative to the axial direction of the screening drum can be adjusted. In this way, the speed of travel of the material along the screening drum can be adjusted as needed.

[0013] Furthermore, the screening drum is composed of a framework and multiple sets of concave plate screen bodies. Specifically, the framework includes two rolling flanges at each end and a central connecting plate arranged in a circular array between the two rolling flanges. Multiple mounting rings are arranged parallel to the rolling flanges. Together, the central connecting plates and mounting rings divide the screening surface of the screening drum into multiple sections, each of which is secured with an arc-shaped concave plate screen body. This ensures a reliable structure for the entire screening drum and reduces manufacturing complexity by dividing the screening surface into multiple concave plate screen bodies.

[0014] Furthermore, the cross-section of the intermediate connecting plate is U-shaped, comprising a bottom plate portion and side plate portions on both sides. A pair of edges in the concave plate sieve body are connected to the side plate portions of the intermediate connecting plate, and the other pair of edges are connected to the mounting ring. The bottom plate portion of the intermediate connecting plate has sieve holes and also has axially extending strip holes. Each concave plate sieve body includes a grass guide plate mounting piece located in the middle, and the grass guide plate mounting piece has a plurality of mounting holes arranged in a linear array; one end of the grass guide plate is connected to the mounting hole and is rotatably connected relative to the grass guide plate mounting piece, and the other end of the grass guide plate is connected to the strip hole by a screw. The screw can be adjusted along the strip hole to change the angle of the grass guide plate. After the adjustment is completed, the grass guide plate is locked and fixed by the screw.

[0015] Furthermore, the threshing drum includes multiple groups of threshing components arranged in a circular array around the central axis. Each group of threshing components includes a rod member, a short-grained rod fixed to the front end of the rod member, and a plurality of toothed rods arranged in a linear array fixed to the rear end of the rod member. The threshing drum also includes two end plates and two intermediate support plates. The rod member is fixed between the two end plates and is also fixedly connected to each intermediate support plate. The central axis is also fixedly connected to the end plates and the intermediate support plates.

[0016] Beneficial effects: The threshing system with a reverse screening drum of the present invention has the following beneficial effects:

[0017] (1) The transmission relationship between the threshing drum and the screening drum is established through a transmission system composed of a transition shaft, a same-direction transmission component and a gear set. On the one hand, the threshing drum and the screening drum can be rotated in opposite directions. The structure is simple and no additional power source is required to drive the screening drum to operate, which can reduce costs. On the other hand, the rotation speed of the screening drum can always be adapted to the speed of the threshing drum. On the third hand, the transmission system can play a deceleration role, so that the rotation speed of the screening drum is much lower than the rotation speed of the threshing drum. The slower rotation speed of the screening drum can enable the screening drum to achieve a better screening effect. The reverse rotation of the screening drum can enable the screens around the screening drum to rotate to perform the screening operation, reduce the probability of screen hole blockage, and improve the cleaning efficiency.

[0018] (2) The layout of the gear assembly enables the two ends of the screening drum to be uniformly stressed, the screening drum will not be twisted and deformed due to uneven stress at the two ends, and the position of the driving force on the screening drum is very close to the rolling flange, and the screening drum does not have the risk of being stuck when rolling.

[0019] (3) The installation of the grass guide assembly is reasonable, the grass guide plate mounting piece is arranged on the concave plate sieve body, and the strip-shaped hole is arranged on the middle connecting plate of the framework, so that the grass guide plate can be conveniently installed, and the inclination angle of the grass guide plate can be conveniently adjusted. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 is a front view of the threshing system;

[0021] Figure 2 is a perspective view of the threshing system;

[0022] Figure 3 is a perspective view of the screening drum;

[0023] Figure 4 is Figure 3 is an enlarged view of part A;

[0024] Figure 5 is Figure 3 is an enlarged view of part B;

[0025] Figure 6 is a structural view of the threshing drum;

[0026] Figure 7 is a structural view of the concave plate sieve body;

[0027] Figure 8 is a structural view of the rolling guide frame;

[0028] Figure 9 is a partial structural view of the screening drum in the preferred embodiment.

[0029] In the drawings: 1-screening drum; 11-rolling flange; 12-concave plate sieve body; 12a-grass guide plate mounting piece; 12b-arc-shaped plate; 12c-straight plate; 12d-slot; 13-middle connecting plate; 13a-sieve hole; 13b-strip-shaped hole; 14-mounting ring; 2-threshing drum; 21-middle shaft; 2A-threshing component; 22-rod; 23-short fluted rod; 24-toothed rod; 25-end plate; 26-middle support plate; 27-conical drum section; 3-transition shaft; 4-constant direction transmission component; 41-first sprocket; 42-second sprocket; 43-chain; 5-gear set; 51-first gear; 52-second gear; 6-rolling guide frame; 61-frame body; 62-rolling wheel; 7-cover body; 8-grass guide assembly; 81-grass guide plate; 9-bolt. DETAILED DESCRIPTION

[0030] The present invention will be further described below with reference to the accompanying drawings.

[0031] like Figure 1-2 The threshing system with a reverse screening drum shown in the figure comprises a cylindrical screening drum 1 and a threshing drum 2 arranged concentrically with the screening drum 1; the threshing drum 2 is connected to a power source, which can be a rotational torque directly or indirectly transmitted by a motor or an engine; the rotation direction of the threshing drum 2 is opposite to the rotation direction of the screening drum 1.

[0032] like Figure 3 As shown, the screening drum 1 is composed of a skeleton and multiple groups of concave plate screen bodies 12. Specifically, the skeleton includes two rolling flanges 11 at both ends, and also includes an intermediate connecting plate 13 arranged in a circumferential array between the two rolling flanges 11. There are also multiple mounting rings 14 arranged parallel to the two rolling flanges 11; in this way, the intermediate connecting plate 13 and the mounting rings 14 divide the screen surface of the screening drum 1 into multiple blocks, and each block is installed with an arc-shaped concave plate screen body 12. In this way, the entire screening drum 1 is not only structurally reliable, but the screen surface is also split into multiple concave plate screen bodies 12, which reduces the manufacturing difficulty. The concave plate screen body 12 has a screen mesh, with arc-shaped plates 12b at both axial ends of the screen mesh and straight plates 12c installed at both radial ends of the screen mesh.

[0033] like Figure 6 As shown, the threshing drum 2 includes multiple groups of threshing components 2A arranged in a circular array around a central axis 21. Each group of threshing components 2A includes a rod 22. A short-grained rod 23 is fixed to the front end of the rod 22, and a plurality of toothed rods 24 arranged in a linear array are fixed to the rear end of the rod 22. The threshing drum 2 also includes two end plates 25 and two intermediate support plates 26. The rod 22 is fixed between the two end plates 25 and is also fixedly connected to each intermediate support plate 26. The central axis 21 is also fixedly connected to the end plates 25 and the intermediate support plates 26. The kneading action between the short-grained rods 23 and the screening drum 1 can help the grains separate from the crop stems. The short-grained rods 23 then strike the stems, forcing the grains that have already separated from the stems but are still mixed in the stems out of the stalk pile. The threshing drum 2 also includes a tapered drum section 27.

[0034] A cover 7 is provided above the screening drum 1. The projection of the cover 7 in the axial direction of the screening drum 1 is narrow at the top and wide at the bottom. In this embodiment, the axial projection is a trapezoid. The cover 7 blocks the seeds thrown out of the upper screen of the screening drum 1, preventing them from scattering and loss.

[0035] The threshing system further comprises a transition shaft 3, which is in driving relationship with the central shaft 21 of the threshing cylinder 2 through a same-direction driving component 4, so that the transition shaft 3 rotates in the same direction as the central shaft 21. The transition shaft 3 is fixed with a first gear 51, and the screening cylinder 1 is fixed with a second gear 52, and the first gear 51 directly engages with the second gear 52.

[0036] Preferably, the same-direction driving component 4 comprises a first sprocket 41 fixed on the central shaft 21 and a second sprocket 42 fixed on the transition shaft 3. The first sprocket 41 and the second sprocket 42 transmit power through a chain 43.

[0037] With the above structure, the driving relationship between the threshing cylinder 2 and the screening cylinder 1 is established through the transmission system composed of the transition shaft 3, the same-direction driving component 4 and the gear set 5. On the one hand, the reverse rotation of the threshing cylinder 2 and the screening cylinder 1 can be realized, the structure is simple, and the additional power source is not needed to drive the screening cylinder 1 to rotate, which can reduce the cost. On the second hand, the rotating speed of the screening cylinder 1 can always be adapted to the speed of the threshing cylinder 2. On the third hand, the number of teeth of the first sprocket 41 is less than the number of teeth of the second sprocket 42, and the number of teeth of the first gear 51 is less than the number of teeth of the second gear 52, so that the above transmission system can play a role of speed reduction, so that the rotating speed of the screening cylinder 1 is much smaller than the rotating speed of the threshing cylinder 2. The slower rotating speed of the screening cylinder 1 can make the screening cylinder 1 have a better screening effect (too fast rotating speed of the screening cylinder 1 will affect the screening effect), and the reverse rotation of the screening cylinder 1 can make the screens around the screening cylinder 1 rotate to perform the screening work, which can reduce the probability of screen hole blockage and improve the screening efficiency. In the embodiment, the speed reduction ratio of the same-direction driving component 4 is 51:15, the speed reduction ratio of the gear set 5 is 135:28, and the total speed reduction ratio of the transmission system is 16.4.

[0038] Preferably, the two ends of the screening cylinder 1 are both fixed with the second gears 52, and the two ends of the transition shaft 3 are also both fixed with the first gears 51, and the first gears 51 and the second gears 52 engage one by one. In this way, the two ends of the screening cylinder 1 can be uniformly stressed, and the screening cylinder 1 will not be twisted and deformed due to uneven stress on the two ends.

[0039] The threshing system further comprises a rolling guide frame 6 arranged corresponding to each rolling flange 11, such as Figure 8As shown, the rolling guide frame 6 includes a frame body 61, and a plurality of rollers 62 rotatably mounted relative to the frame body 61 and arranged along an arc path. The frame body 61 is composed of two arc plates, and all rollers 62 are placed between the two arc plates. The rolling flange 11 is in contact with all rollers 62 in the corresponding rolling guide frame 6. The roller 62 is a grooved wheel with an annular groove in the middle, so that the rolling flange 11 can be kept from contacting the arc plate. The rolling flange 11 located at the same end of the screening drum 1 is installed adjacent to the second gear 52. In this way, the position on the screening drum 1 that is subjected to the driving force is very close to the rolling flange 11, and there is no risk of the screening drum 1 being stuck when rolling.

[0040] The central axis 21 is located laterally of the central axis 21, that is, beside the left or right quadrant of the screening drum 1. Therefore, the meshing position of the first gear 51 and the second gear 52 avoids the concentrated position of material movement, thereby preventing material from entering between the first gear 51 and the second gear 52. This is also achieved due to the simple and compact design of the transmission system of the present invention.

[0041] like Figure 3 As shown, multiple sets of grass guide assemblies 8 are mounted on the inner wall of the screening drum 1. Each set of grass guide assemblies 8 includes multiple parallel grass guide plates 81, with the ends of the grass guide plates 81 staggered axially with respect to the screening drum 1. As the screening drum 1 rotates, the material passes through the grass guide plates 81. The grass guide plates 81 act on the material, causing it to move axially relative to the screening drum 1, causing it to move forward along the screening drum 1. After cleaning, impurities are discharged from the end of the screening drum 1.

[0042] The inclination angle of the grass guide plate 81 relative to the axial direction of the screening drum 1 can be adjusted. In this way, the speed of the material along the screening drum 1 can be adjusted as needed. The grass guide plate 81 is installed on the shaft section corresponding to the short-grain rod 23, which can achieve a good propulsion effect.

[0043] In one embodiment, the cross section of the intermediate connecting plate 13 is U-shaped, which includes a bottom plate portion and side plate portions on both sides. A pair of edges of the concave plate sieve body 12 are connected to the side plate portions of the intermediate connecting plate 13, and the other pair of edges are connected to the mounting ring 14. Figure 4 As shown, the bottom plate portion of the intermediate connecting plate 13 has a sieve hole 13a and an axially extending strip hole 13b. Figure 7 As shown, each concave plate screen body 12 includes a grass guide plate mounting member 12a located in the middle, and the grass guide plate mounting member 12a has a plurality of mounting holes arranged in a linear array; Figure 5As shown, one end of the grass guide plate 81 is connected to the mounting hole and is rotatably connected relative to the grass guide plate mounting piece 12a, and the other end of the grass guide plate 81 is connected to the strip hole 13b through a screw (not shown in the figure). The screw can adjust its position along the strip hole 13b to change the angle of the grass guide plate 81. After the adjustment is completed, the grass guide plate 81 is locked and fixed by the screw.

[0044] In another embodiment, the intermediate connecting plate 13 also has sieve holes 13a and strip holes 13b, and the functions of the sieve holes 13a and strip holes 13b are exactly the same as those in the previous embodiment. Figure 9 As shown, the inner side of the curved plate 12b of the concave plate screen body 12 has a slot 12d, which makes the concave plate screen body 12 as a whole have elastic bending ability. The intermediate connecting plate 13 can move and fix its position in the radial direction of the mounting ring 14. The straight plate 12c of the concave plate screen body 12 is located on the outside of the intermediate connecting plate 13. The straight plates 12c of two adjacent concave plate screen bodies 12 that are close to each other are located on the outside of the same intermediate connecting plate 13 and are connected by bolts 9 located on the outside of the intermediate connecting plate 13. In this way, the roller gap between the concave plate screen body 12 and the threshing component 2A can be changed by tightening or loosening the bolts. After adjusting the gap, the intermediate connecting plate 13 is fixed relative to the mounting ring 14. The above-mentioned adjustment structure is relatively simple, the structural changes are small, and the structural volume will not be increased.

[0045] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A threshing system with a reverse screening drum, comprising a cylindrical screening drum (1) and a threshing drum (2) arranged concentrically with the screening drum (1); the threshing drum (2) is connected to a power source; the rotation direction of the threshing drum (2) is opposite to the rotation direction of the screening drum (1); Its characteristics are: It also includes a transition shaft (3), wherein a transmission relationship is established between the transition shaft (3) and the central shaft (21) of the threshing drum (2) via a same-direction transmission component (4); a first gear (51) is fixed on the transition shaft (3), and a second gear (52) is fixed on the screening drum (1), and the first gear (51) and the second gear (52) are directly meshed; The screening drum comprises a skeleton, which comprises two rolling flanges at both ends and an intermediate connecting plate arranged in a circular array between the two rolling flanges. There are also multiple mounting rings arranged parallel to the two rolling flanges between the two rolling flanges. The intermediate connecting plate and the mounting ring divide the screen surface of the screening drum into multiple blocks, and each block is equipped with a concave plate screen body, the concave plate screen body has a screen, and the axial ends of the screen are provided with arc plates, and the radial ends of the screen are equipped with straight plates; the cross-section of the intermediate connecting plate is U-shaped, which includes a bottom plate portion and side plate portions on both sides, a pair of edges in the concave plate screen body are connected to the side plate portions of the intermediate connecting plate, and the other pair of edges are connected to the mounting ring; the inner side of the arc plate has a slot, so that the concave plate screen body as a whole has elastic bending ability, the intermediate connecting plate can move and fix its position in the radial direction of the mounting ring, the straight plate is located on the outer side of the intermediate connecting plate, and the straight plates of the two adjacent concave plate screen bodies that are close to each other are located on the outer side of the same intermediate connecting plate, and are connected by bolts located on the outer side of the intermediate connecting plate. The gap between the concave plate screen body and the threshing drum can be changed by tightening or loosening the bolts.

2. The threshing system with a reverse screening drum according to claim 1, characterized in that The same-direction transmission component (4) comprises a first sprocket (41) fixed on the central shaft (21) and a second sprocket (42) fixed on the transition shaft (3); power is transmitted between the first sprocket (41) and the second sprocket (42) via a chain (43).

3. The threshing system with a reverse screening drum according to claim 1, characterized in that The second gear (52) is fixed on the screening drum (1), the first gear (51) is fixed on the transition shaft (3), and the first gear (51) and the second gear (52) are correspondingly meshed.

4. The threshing system with a reverse screening drum according to claim 1, characterized in that A cover body (7) is provided above the screening drum (1), and the projection of the cover body (7) in the axial direction of the screening drum (1) is in a shape that is narrow at the top and wide at the bottom.

5. The threshing system with a reverse screening drum according to claim 1, characterized in that A plurality of grass guide assemblies (8) are installed on the inner wall of the screening drum (1), and each group of the grass guide assemblies (8) comprises a plurality of grass guide plates (81) arranged in parallel, and the two ends of the grass guide plates (81) are staggered in the axial direction of the screening drum (1).

6. The threshing system with a reverse screening drum according to claim 1, characterized in that The threshing drum (2) comprises a plurality of groups of threshing components (2A) arranged in a circular array around the central axis (21), each group of the threshing components (2A) comprises a rod (22), a short-grained rod (23) is fixed to the front section of the rod (22), and a plurality of toothed rods (24) arranged in a linear array are fixed to the rear section of the rod (22).

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