CN117413694A - An axial-flow coaxially coupled corn threshing inner and outer double drum - Google Patents

Abstract

The invention belongs to the field of agricultural machinery and discloses an axial flow coaxially coupled corn threshing inner and outer double drum, which includes: a first spiral feeding head, which includes a first conical head and a plurality of first spiral blades; a first cone The head is a tapered cylinder with an open large-diameter end; the first cylinder is a cylinder with one end open; the open end of the first cylinder is coaxially fixedly connected to the large-diameter end of the first spiral feeding head; The first cylinder is provided with multiple sets of particle discharge openings; the second spiral feeding head includes a second conical head and a plurality of second spiral blades; the second cylinder is a cylinder and is coaxially arranged on In the first cylinder; one end of the second cylinder is fixedly connected to the small diameter end of the second screw feeding head; a plurality of convex ribs are provided on the outer wall of the second cylinder, and the convex ribs are arranged along the axial direction of the second cylinder; A first threshing element is provided on the outer wall of the first cylinder, and a second threshing element is provided on the inner wall; the first cylinder and the second cylinder can rotate in opposite directions respectively driven by the driving device.

Description

An axial-flow coaxially coupled corn threshing inner and outer double drum

Technical field

The invention belongs to the technical field of agricultural machinery, and particularly relates to an axial-flow coaxially coupled corn threshing inner and outer double drum.

Background technique

Corn is one of the main food crops in my country. In the corn production process, harvesting is one of the most critical and important links, and it is also the link that consumes the most labor and time. With the popularization of corn harvest mechanization, direct grain harvesting technology has gradually become a hot issue in the industry. The current mainstream corn threshing device uses a longitudinal-axial flow corn threshing drum to thresh, separate and remove impurities from the corn transported by the conveyor device. However, the single longitudinal axial flow corn threshing drum can only use one drum to operate the corn, and the large internal space is not properly utilized, resulting in serious waste of space, thus limiting the threshing efficiency of direct harvesting of corn kernels.

Although the existing double longitudinal axial flow corn threshing drum can improve threshing efficiency, the overall structure is huge and is not suitable for small plot operations. Therefore, there is currently no technology available for reference on how to improve the threshing efficiency of the corn threshing drum while also making the threshing drum occupy a smaller space and be suitable for small plot operations.

Contents of the invention

The object of the present invention is to provide an axial-flow coaxially coupled inner and outer double drum for corn threshing, which is provided with two inner and outer threshing drums and can fully utilize the internal space of a single longitudinal axial flow corn threshing drum without increasing the occupied space. Under the premise of improving threshing efficiency.

The technical solution provided by the invention is:

An axial flow coaxially coupled corn threshing inner and outer double drum, including:

A first spiral feed head, which includes a first conical head and a plurality of first spiral blades;

Wherein, the first cone-shaped head is a cone-shaped cylinder; the large-diameter end of the first cone-shaped head is open and the small-diameter end is closed; the first spiral blade is spirally fixed on the first cone. On the outer wall of the shaped head; the first conical head is provided with a plurality of ear feeding inlets;

The first cylinder is a cylinder with one end open and the other end closed; the open end of the first cylinder is coaxially fixedly connected to the large diameter end of the first screw feeding head; The first cylinder is provided with a plurality of sets of grain discharge openings for discharging the corn kernels in the first cylinder;

a second spiral feeding head, which includes a second conical head and a plurality of second spiral blades; the second spiral blades are spirally fixed on the outer wall of the second conical head;

Wherein, the second spiral feeding head is coaxially disposed in the first conical head, and the second spiral blade and the first spiral blade have opposite directions of rotation;

The second cylinder is a cylinder and is coaxially arranged in the first cylinder; one end of the second cylinder is fixedly connected to the small diameter end of the second spiral feeding head, and the other end is closed; A plurality of convex ribs are provided on the outer wall of the second cylinder, the convex ribs are arranged along the axial direction of the second cylinder, and the plurality of convex ribs are arrayed along the circumferential direction of the second cylinder;

A plurality of sets of first threshing elements, which are arranged on the outer wall of the first cylinder and are spaced apart along the axial direction of the first cylinder;

A plurality of sets of second threshing elements, which are arranged on the inner wall of the first cylinder and are spaced apart along the axial direction of the first cylinder;

Wherein, there is a gap between the second threshing element and the convex rib; the first cylinder and the second cylinder can rotate respectively under the drive of the driving device, and the first cylinder and the The rotation direction of the second cylinder is opposite.

Preferably, the axial-flow coaxially coupled inner and outer double drums for corn threshing also include:

A plurality of sets of first threshing separation elements, which are arranged on the outer wall of the first cylinder and spaced along the axial direction of the first cylinder;

A plurality of sets of second threshing separation elements are arranged on the inner wall of the first cylinder and are spaced apart along the axial direction of the first cylinder;

Wherein, there is a gap between the second threshing separation element and the convex rib.

Preferably, the particle discharge openings include: a first row of particle openings and a second row of particle openings; the width of the first row of particle openings is smaller than the width of the second row of particle openings;

Wherein, multiple sets of first rows of particle openings are arranged along the axial direction of the first cylinder and are arranged close to the open end of the first cylinder; multiple sets of second rows of particle openings are arranged along the axis of the first cylinder. To the array, and arranged close to the closed end of the first barrel;

Each group of the first row of grain openings is located between two adjacent groups of first threshing elements; each group of the second row of grain openings is located between two adjacent groups of first threshing separation elements or the first threshing element is adjacent to the first row of grain openings. between adjacent first threshing separation elements;

Wherein, the position of each group of second threshing elements corresponds to the position of each group of first threshing elements; the position of each group of second threshing separation elements corresponds to the position of each group of first threshing separation elements. One-to-one correspondence.

Preferably, the convex rib is a hollow cylindrical structure, and both ends of the convex rib are closed.

Preferably, the first threshing element and the first threshing separation element are distributed in a spiral around the axis of the first cylinder.

Preferably, the axial-flow coaxially coupled inner and outer double drums for corn threshing also include:

A plurality of first rows of miscellaneous plates, which are fixedly arranged on the outer wall of the closed end of the first cylinder, and the plurality of first rows of miscellaneous plates are arrayed along the circumferential direction of the first cylinder;

A plurality of garbage discharge openings are arranged between two adjacent first row garbage boards.

Preferably, the axial-flow coaxially coupled inner and outer double drums for corn threshing also include:

A plurality of second rows of miscellaneous plates are fixedly arranged on the outer wall of the closed end of the second cylinder, and the plurality of second rows of miscellaneous plates are arrayed along the circumferential direction of the second cylinder.

Preferably, a partition is fixed inside the first conical head, the partition is parallel to the end plate of the first conical head, and a gap is formed between the partition and the end plate of the first conical head. cavity;

Wherein, an annular groove is provided on the partition plate; an annular boss is provided on the large diameter end of the second conical head, and the annular boss is matchingly arranged in the annular groove and can be positioned relative to the The annular groove rotates.

Preferably, the axial-flow coaxially coupled inner and outer double drums for corn threshing also include:

A plurality of through holes are opened on the partition plate and located within the ring of the annular groove.

Preferably, a solid shaft runs coaxially through the second cylinder, and the solid shaft is fixedly connected to the second cylinder; a hollow shaft is coaxially and fixedly connected to the first conical head, and the hollow shaft The hollow sleeve is placed on the solid shaft;

Wherein, the driving device can drive the solid shaft and the hollow shaft to rotate in opposite directions respectively.

The beneficial effects of the present invention are:

(1) The invention provides an axial-flow coaxially coupled inner and outer double drum for corn threshing, which is provided with inner and outer double threshing drums. While the outer threshing drum is threshing the corn, the inner threshing drum is also working, which avoids the need for internal construction of the threshing drum. The waste of large space improves the corn threshing efficiency.

(2) The axial-flow coaxially coupled inner and outer double drums for corn threshing provided by the present invention adopt the design of double screw feeding heads, which can effectively sort and transport large feeding volumes, avoid clogging of the feeding inlet, and can It effectively increases the corn feeding amount per unit time and further improves the corn threshing efficiency; and through the design of grooves, bosses and through holes, dust accumulation can be prevented from affecting the work of the feeding head.

(3) The threshing elements in the first cylinder cooperate with the convex ribs on the second cylinder for threshing. The convex ribs are large in number and relatively dense, which is beneficial to increasing the number of collisions with the ears and reducing the rate of corn not being threshed.

(4) The axial-flow coaxially coupled inner and outer double drums of corn threshing are improved on the existing single longitudinal axial flow corn threshing drum, achieving efficient use of internal space, and can be better used for existing combine harvesters. Adaptation facilitates low-cost promotion and utilization in real life.

Description of the drawings

Figure 1 is a schematic diagram of the overall structure of an axial flow coaxially coupled corn threshing inner and outer double drum according to the present invention.

Figure 2 is a schematic structural diagram of the second cylinder according to the present invention.

Figure 3 is a schematic cross-sectional view of the first cylinder and the second cylinder according to the present invention.

Figure 4 is a schematic transverse cross-sectional view of the coupling threshing element between the first cylinder and the second cylinder according to the present invention.

Figure 5 is a schematic structural diagram of the partition plate of the first screw feeding head according to the present invention.

Figure 6 is a schematic diagram of the cooperation between the second screw feeding head and the first screw feeding head according to the present invention.

Figure 7 is a schematic diagram of the installation method of the solid shaft and the hollow shaft according to the present invention.

Figure 8 is a schematic diagram of the tail cover of the first cylinder according to the present invention.

Detailed ways

The present invention will be further described in detail below with reference to the accompanying drawings, so that those skilled in the art can implement it with reference to the text of the description.

As shown in Figures 1-8, the present invention provides an axial flow coaxially coupled inner and outer double drum for corn threshing, which mainly includes a first spiral feeding head 1, a second spiral feeding head 2, and a first threshing element 3 , the first threshing and separation element 4, the first cylinder 5, the first row of impurity plates 6, the second row of impurity plates 7, the second threshing element 8, the second threshing and separation element 9 and the second cylinder 10.

The first spiral feeding head 1 includes a first conical head and a plurality of first spiral blades; wherein, the first conical head is a conical cylinder; the large diameter end of the first conical head is open, and the small diameter end of the first conical head is open. The diameter end is closed by an end plate; the first spiral blade is spirally wound around the axis of the first conical head and fixed on the outer wall of the first conical head; a plurality of second spiral blades are equally spaced layout.

The first cylinder 5 is a cylinder. One end of the first cylinder 5 is open and the other end is closed by a tail cover 16 . Among them, the tail cover 16 is connected to the first cylinder 5 through bolts to facilitate the disassembly and installation of the first cylinder 5. The open end of the first cylinder 5 is coaxially and fixedly connected to the large diameter end of the first screw feeding head 1 , and the diameter of the opening end of the first cylinder 5 and the large diameter end of the first screw feeding head 1 are the same. A plurality of ear feeding inlets 1a are provided on the side wall of the first conical head, and the ear feeding inlets 1a are opened close to the large diameter section of the first conical head; corn ears enter the first tube through the ear feeding inlets 1a. In body 5. The first cylinder 5 is provided with multiple sets of grain discharge openings for discharging the corn kernels in the first cylinder 5 . Preferably, the edge of the ear feeding port 1a is a smooth arc, and one side of the ear feeding port 1a is provided along the bottom of the first spiral blade to prevent the corn ears from being stuck when entering.

The second spiral feeding head 2 includes a second conical head and a plurality of second spiral blades; the second conical head is conical, and the second spiral blades are spiral around the axis of the second conical head. Winding and fixed on the outer wall of the second conical head. A plurality of second spiral blades are arranged at equal intervals. Wherein, the second spiral feeding head 2 is coaxially arranged in the first conical head, and the spiral directions of the second spiral blade and the first spiral blade are opposite.

The second cylinder 10 is a cylinder, and the length of the second cylinder 10 is slightly smaller than the length of the first cylinder 5; the second cylinder 10 is coaxially arranged inside the first cylinder 5. One end of the second cylinder 10 is fixedly connected to the small diameter end of the second screw feeding head 2, and the other end of the second cylinder 10 is closed. A plurality of convex ribs 11 are provided on the outer wall of the second cylinder 10 . The convex ribs 11 are arranged along the axial direction of the second cylinder 10 . The plurality of convex ribs 11 are arrayed along the circumferential direction of the second cylinder 10 . The number of convex ribs 11 on the second cylinder 10 is large, relatively dense, and arranged in a concave plate shape imitating a circular tube, which is beneficial to increasing the number of collisions with corn ears and reducing the non-cleaning rate during corn operations.

Multiple sets of first threshing elements 3 are arranged on the outer wall of the first cylinder 5 , and multiple sets of first threshing elements 3 are arranged at intervals along the axial direction of the first cylinder 5 . Multiple sets of second threshing elements 8 are provided on the inner wall of the first cylinder 5 and are spaced apart along the axial direction of the first cylinder 5 . Multiple sets of first threshing and separation elements 4 are arranged on the outer wall of the first cylinder 5 and are spaced apart along the axial direction of the first cylinder 5 . Multiple sets of second threshing separation elements 9 are arranged on the inner wall of the first cylinder 5 and are spaced apart along the axial direction of the first cylinder 5 . The first cylinder 5, the first threshing element 3, the first threshing separation element 4, the second threshing element 8, the second threshing separation element 9 and the discharge opening form an outer threshing drum; the second cylinder 10 and The convex rib 11 forms the inner threshing drum. There is a gap between the second threshing element 8 and the second threshing separation element 9 and the protruding rib 11 respectively. The first cylinder 5 and the second cylinder 10 can rotate respectively under the drive of the driving device, and the rotation directions of the first cylinder 5 and the second cylinder 10 are opposite.

Preferably, the particle discharge openings include: a first row of particle openings 5a and a second row of particle openings 5b; the width of the first row of particle openings 5a is smaller than the width of the second row of particle openings 5b. Among them, multiple groups of first rows of particle openings 5a are arranged along the axial direction of the first cylinder 5, and multiple groups of first rows of particle openings 5a are arranged close to the open end of the first cylinder 5; multiple groups of second rows of particle openings 5b are arranged along the axial direction of the first cylinder 5. The first cylinder 5 is axially arrayed, and multiple sets of second rows of particle openings 5b are arranged close to the closed end of the first cylinder 5 . Each group of the first row of grain openings 5a is located between two adjacent groups of first threshing elements 3; each group of the second row of grain openings 5b is located between two adjacent groups of first threshing separation elements 4 or (the last group ) between the first threshing element 3 and its adjacent (first group) first threshing separation element 4. Each group of first rows of particle openings 5 a has multiple first rows of particle openings, and the plurality of first rows of particle openings are arrayed along the circumferential direction of the first cylinder 5 . Each group of first rows of particle openings 5b has a plurality of second rows of particle openings, and the plurality of first rows of particle openings are arrayed along the circumferential direction of the first cylinder 5 . Among them, the position of each group of second threshing elements 8 corresponds to the position of each group of first threshing elements 3; the position of each group of second threshing separation elements 9 corresponds to the position of each group of first threshing separation elements 4. Among them, the first threshing element 3 and the second threshing element 8 adopt textured bar threshing elements, and the first threshing separation element 4 and the second threshing separation element 9 adopt nail-tooth threshing separation elements.

By arranging the first row of grain openings 5a and the second row of grain openings 5b with different widths on the first cylinder, the first threshing element 3, the second threshing element 8, the first threshing separation element 4, and the second threshing separation element 9 The arrangement provides a reasonable installation space; the spacing between the first (second) threshing elements is smaller, which increases the number of threshing elements in the threshing section, increases the frequency of the threshing elements hitting the corn ears, and improves the threshing efficiency. and the threshing rate; at the same time, appropriately increasing the spacing between the first (second) threshing separation elements can reduce the number of elements in the threshing separation section, reduce the quality of the drum, and reduce power consumption.

As a preference, each group of first threshing elements 3 includes a plurality of first threshing separation elements, and the plurality of first threshing elements in the same group are arranged at intervals along the circumferential direction of the first cylinder 5; each group of first threshing separation elements 4 includes a plurality of first threshing separation elements, and the plurality of first threshing separation elements in the same group are arranged at intervals along the circumferential direction of the first cylinder 5 . The first threshing element and the first threshing separation element are distributed in multiple spirals around the outer wall of the first cylinder 5; correspondingly, the second threshing element and the second threshing separation element are arranged in the first cylinder There are multiple spirals distributed on the inner wall of 5; this can make the corn flow smoother during operation, reduce the phenomenon of corn kernels getting stuck or blocked, and improve the efficiency of corn threshing.

As a further preference, the convex rib 11 is configured as a hollow cylindrical (tube) structure, and both ends of the convex rib 11 are closed. Setting the rib 11 into a hollow structure can reduce the mass of the second cylinder and reduce power consumption.

A plurality of first trash discharge plates 6 are fixedly arranged on the outer wall of the closed end of the first cylinder 5. The plurality of first trash discharge plates 6 are arrayed along the circumferential direction of the first cylinder 5; a plurality of trash discharge openings 5c are opened and arranged adjacent to each other. Between the two first rows of debris plates 6, it is used to discharge corn cobs or other debris in the first cylinder 5.

A plurality of second rows of miscellaneous plates 7 are fixedly arranged on the outer wall of the closed end of the second cylinder 10 , and the plurality of second rows of miscellaneous plates 7 are arrayed along the circumferential direction of the second cylinder 10 . There is a gap between the outer edge of the second row of miscellaneous plates 7 and the inner wall of the first cylinder 5 to avoid interference between the two during rotation. Under the guidance of the threshing separation element, debris is discharged through the first row of debris plates 6 and the second row of debris plates 7, ensuring that the threshing operation proceeds smoothly.

As shown in Figures 5-6, in one embodiment, a partition 1b is fixedly installed inside the first conical head. The partition 1b is parallel to the end plate of the first conical head, and the partition 1b is parallel to the end plate of the first conical head. A cavity is formed between the end plates of a tapered head. Among them, the partition 1b is provided with an annular groove 102; the large diameter end of the second conical head is provided with an annular boss 201, the annular boss 201 is matched and embedded in the annular groove 102, and can be positioned relative to the annular Groove 102 rotates. A plurality of through holes 101 are opened on the partition plate 1 b, and are located inside the ring of the annular groove 102 and close to the center of the partition plate 1 b. By providing an annular boss 201 on the large diameter end surface of the second screw feeding head 2, it cooperates with the annular groove 102 on the partition plate 1b of the first screw feeding head 1, and a through hole 101 is opened on the partition plate 1b, Dust can be allowed to enter the cavity between the partition 1b and the end plate of the first conical head through the through hole 101, thereby preventing dust from accumulating between the first spiral feeding head 1 and the second spiral feeding head 2 and affecting the feeding process. Get to work.

As shown in Figures 7-8, in one embodiment, a solid shaft 13 coaxially penetrates the second cylinder 10, and the solid shaft 13 is fixedly connected to the second cylinder 10; the first conical head is coaxially connected A hollow shaft 12 is fixedly provided, and the hollow shaft 12 is hollowly sleeved on the solid shaft 13 . Among them, the outer side of the tail cover 16 is fixedly connected to the flange 14, and a bearing 15 is provided at the center of the flange 14. At the same time, bearings 15 are installed at both ends of the hollow shaft 12, and the solid shaft 13 is rotatably supported in multiple bearings 15.

The driving device can drive the hollow shaft 12 and the solid shaft 13 to rotate in opposite directions respectively, thereby driving the first cylinder 5 and the second cylinder 10 to rotate in the opposite direction. Among them, the rotation speeds of the first cylinder 5 and the second cylinder 10 can be controlled respectively to adjust the threshing speed of the inner and outer threshing drums.

Since the second threshing element 8 and the second threshing separation element 9 are installed inside the first cylinder, the linear speed during rotation is lower than that of the first threshing element 3 and the second threshing separation element 4. With the second cylinder 10's movement in the opposite direction works on the corn, and adjusts the speed of the inner and outer threshing drums respectively, so that the threshing can reach the ideal linear speed, which can further improve the threshing effect.

The working principle of the axial flow coaxial coupling of the inner and outer double drums of corn threshing provided by the present invention is: the corn ears are guided by the first spiral blade on the first spiral feeding head 1 and enter the recesses of the outer threshing drum and the corn threshing separation device respectively. The first-level outer threshing gap formed by the plate and the shell, and the second-level inner threshing gap formed between the outer threshing drum and the inner threshing drum. Wherein, after corn ears enter the first spiral feeding head 1 through the ear feeding inlet 1a on the first spiral feeding head 1, they enter the second spiral feeding head 2 through the push of the second spiral blade. Level threshing gap. The concave plate and shell of the corn threshing and separating device cooperate with the first threshing element 3, the first threshing and separating element 4, and the first impurity discharge plate 6 on the first cylinder 5 to perform threshing and impurity discharge; the second cylinder 10 and The second threshing element 8, the second threshing separation element 9, and the second impurity row plate 7 interact with each other for threshing and impurity removal, realizing the axial flow coaxially coupled corn double drum threshing operation of corn. Among them, the concave plate and the shell are the original structures of the corn threshing and separation device, and will not be described again here.

The invention provides an axial flow coaxially coupled inner and outer double drum for corn threshing, which is provided with an inner and an outer double threshing drum. While the outer threshing drum performs threshing operations on corn, the inner threshing drum also performs threshing operations, making full use of the outer threshing drum. internal space and improves corn threshing efficiency. The present invention adopts the design of a double-spiral feeding head, which can effectively sort and transport large-volume feeding operations, avoid clogging of the feeding inlet, effectively increase the corn feeding amount per unit time, and improve the threshing of corn. Efficiency, the two spiral feeding heads are matched through grooves and bosses, and the through-hole design can prevent dust accumulation from affecting the operation of the feeding heads. In the present invention, the threshing element provided inside the first cylinder cooperates with the convex ribs on the second cylinder for threshing. The convex ribs are large in number and relatively dense, which is beneficial to increasing the number of collisions with the ear and reducing the rate of corn not being threshed.

The axial-flow coaxially coupled inner and outer double drums for corn threshing provided by the present invention are improved on the existing single longitudinal axial flow corn threshing drum, achieving efficient utilization of the internal space and enabling more efficient use of existing combine harvesters. Good adaptation facilitates low-cost promotion and utilization in real life.

Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the description and embodiments. They can be applied to various fields suitable for the present invention. For those familiar with the art, they can easily Additional modifications may be made, and the invention is therefore not limited to the specific details and illustrations shown and described herein without departing from the general concept defined by the claims and equivalent scope.

Claims (10)

1. An axial flow coaxially coupled corn threshing inner and outer double drum, which is characterized by including: A first spiral feed head, which includes a first conical head and a plurality of first spiral blades; Wherein, the first cone-shaped head is a cone-shaped cylinder; the large-diameter end of the first cone-shaped head is open and the small-diameter end is closed; the first spiral blade is spirally fixed on the first cone. On the outer wall of the shaped head; the first conical head is provided with a plurality of ear feeding inlets; The first cylinder is a cylinder with one end open and the other end closed; the open end of the first cylinder is coaxially fixedly connected to the large diameter end of the first screw feeding head; The first cylinder is provided with a plurality of sets of grain discharge openings for discharging the corn kernels in the first cylinder; a second spiral feeding head, which includes a second conical head and a plurality of second spiral blades; the second spiral blades are spirally fixed on the outer wall of the second conical head; Wherein, the second spiral feeding head is coaxially disposed in the first conical head, and the second spiral blade and the first spiral blade have opposite directions of rotation; The second cylinder is a cylinder and is coaxially arranged in the first cylinder; one end of the second cylinder is fixedly connected to the small diameter end of the second spiral feeding head, and the other end is closed; A plurality of convex ribs are provided on the outer wall of the second cylinder, the convex ribs are arranged along the axial direction of the second cylinder, and the plurality of convex ribs are arrayed along the circumferential direction of the second cylinder; A plurality of sets of first threshing elements, which are arranged on the outer wall of the first cylinder and are spaced apart along the axial direction of the first cylinder; A plurality of sets of second threshing elements, which are arranged on the inner wall of the first cylinder and are spaced apart along the axial direction of the first cylinder; Wherein, there is a gap between the second threshing element and the convex rib; the first cylinder and the second cylinder can rotate respectively under the drive of the driving device, and the first cylinder and the The rotation direction of the second cylinder is opposite. 2. The axial flow coaxially coupled inner and outer double drums for corn threshing according to claim 1, characterized in that it also includes: A plurality of sets of first threshing separation elements, which are arranged on the outer wall of the first cylinder and spaced along the axial direction of the first cylinder; A plurality of sets of second threshing separation elements are arranged on the inner wall of the first cylinder and are spaced apart along the axial direction of the first cylinder; Wherein, there is a gap between the second threshing separation element and the convex rib. 3. The axial flow coaxially coupled inner and outer double drum of corn threshing according to claim 2, characterized in that the grain discharge opening includes: a first row of grain openings and a second row of grain openings; The width is smaller than the width of the second row of grain openings; Wherein, multiple sets of first rows of particle openings are arranged along the axial direction of the first cylinder and are arranged close to the open end of the first cylinder; multiple sets of second rows of particle openings are arranged along the axis of the first cylinder. To the array, and arranged close to the closed end of the first barrel; Each group of the first row of grain openings is located between two adjacent groups of first threshing elements; each group of the second row of grain openings is located between two adjacent groups of first threshing separation elements or the first threshing element is adjacent to the first row of grain openings. between adjacent first threshing separation elements; Wherein, the position of each group of second threshing elements corresponds to the position of each group of first threshing elements; the position of each group of second threshing separation elements corresponds to the position of each group of first threshing separation elements. One-to-one correspondence. 4. The axial-flow coaxially coupled inner and outer double drum for corn threshing according to claim 3, characterized in that the convex rib is a hollow cylindrical structure, and both ends of the convex rib are closed. 5. The axial flow coaxially coupled inner and outer double drum of corn threshing according to claim 3 or 4, characterized in that the first threshing element and the first threshing separation element surround the axis of the first cylinder Distributed in a spiral. 6. The axial flow coaxially coupled inner and outer double drums for corn threshing according to claim 5, characterized in that it also includes: A plurality of first rows of miscellaneous plates, which are fixedly arranged on the outer wall of the closed end of the first cylinder, and the plurality of first rows of miscellaneous plates are arrayed along the circumferential direction of the first cylinder; A plurality of garbage discharge openings are arranged between two adjacent first row garbage boards. 7. The axial flow coaxially coupled inner and outer double drums for corn threshing according to claim 6, characterized in that it also includes: A plurality of second rows of miscellaneous plates are fixedly arranged on the outer wall of the closed end of the second cylinder, and the plurality of second rows of miscellaneous plates are arrayed along the circumferential direction of the second cylinder. 8. The axial flow type coaxially coupled corn threshing internal and external double drum according to claim 7, characterized in that a partition is fixedly provided in the first conical head, and the partition between the partition and the first conical head The end plates are parallel, and a cavity is formed between the partition plate and the end plate of the first tapered head; Wherein, an annular groove is provided on the partition plate; an annular boss is provided on the large diameter end of the second conical head, and the annular boss is matchingly arranged in the annular groove and can be positioned relative to the The annular groove rotates. 9. The axial flow coaxially coupled corn threshing inner and outer double drum according to claim 8, characterized in that it also includes: A plurality of through holes are opened on the partition plate and located within the ring of the annular groove. 10. The axial flow coaxially coupled internal and external corn threshing drum according to claim 9, characterized in that a solid shaft coaxially penetrates the second cylinder, and the solid shaft is fixedly connected to the second cylinder. ; A hollow shaft is coaxially fixedly connected to the first conical head, and the hollow shaft is hollowly sleeved on the solid shaft; Wherein, the driving device can drive the solid shaft and the hollow shaft to rotate in opposite directions respectively.