Floating type cyperus esculentus digging table, harvester and control method

Abstract

The invention discloses a floating type cyperus esculentus digging table, a harvester and a control method, and belongs to the technical field of tuber crop harvesting.The digging table comprises a machine frame, a rotary tillage assembly is installed at the front end of the machine frame, and a lifting sieve located behind the rotary tillage assembly is installed in the middle of the machine frame; a hinge seat is mounted at the upper part of the rear end of the rack; the front end of a hydraulic cylinder hinged to the machine body is hinged to the lower side of the rear portion of the machine frame. A driving motor is installed on the machine frame, an output shaft of the driving motor is connected with a first chain transmission mechanism and a second chain transmission mechanism, and the first chain transmission mechanism is connected with a transmission shaft at the rear end of the lifting screen. And an angle sensor is mounted on the rack. According to the mandulapalka harvester, the digging depth can be accurately controlled, the soil digging amount is reduced, oil consumption is reduced, the strong soil screening capacity is achieved, the soil content conveyed to the harvester can be greatly reduced, and the mandulapalka harvesting efficiency and quality are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of root crop harvesting and relates to a floating cyperus oleifera digging platform, a harvester and a control method. Background Art

[0002] Cyperus oleiferus, also known as Cyperus oleiferus, tiger nut, and iron water chestnut, is an annual herbaceous plant of the Cyperaceae family. It has leaves on the ground and fruits underground. The fruit is a granular tuber, which is yellow-brown in color. Its shape and size are similar to those of yam fruit. It is a new agricultural product with extremely high comprehensive benefits. Cyperus oleiferus is a treasure from head to toe. It is easy to plant and manage, but difficult to harvest. In the process of harvesting cyperus oleiferus, efficient and low-loss excavation of the bean plant is the key. For the excavation stage of harvesting, the existing main means is still to excavate the plant by rotary tillage. However, during harvesting, the excavation depth is too shallow, and the cyperus oleiferus plant cannot be excavated as a whole, resulting in an increase in the fruit leakage rate; if the excavation depth is too deep, the mechanical consumables will increase and the tractor power consumption will increase, reducing the operation efficiency. Therefore, the control of the excavation depth is the key to efficient and low-loss excavation of cyperus oleiferus. At present, the monitoring of the excavation depth of the soil layer during the harvesting process is mainly based on manual measurement. The staff needs to select a large number of measurement points in the forward direction of the unit, manually dig the soil, and use the tillage depth gauge for measurement. The measurement accuracy is low and the labor intensity is high, which greatly reduces the efficiency of the harvesting operation. At the same time, since the digging depth data cannot be accurately controlled, the driver often needs to judge the digging effect based on personal experience. If the digging depth does not meet the standard, it is easy to miss the fruit, affecting the harvest quality. If the digging depth is too deep, the walking resistance is large, and the fuel consumption increases significantly after working for a long time. Therefore, in the process of cyperus rotundus harvesting, the precise control of the rotary tillage depth is the key to ensuring the harvest quality, improving the working efficiency and reducing the energy loss. It is also one of the problems that the improved cyperus rotundus harvester needs to solve urgently. Summary of the invention

[0003] In order to overcome the deficiencies in the prior art, the present invention provides a floating cyperus oleifera digging platform, a harvester and a control method. The purpose is to design a floating cyperus oleifera digging platform and a harvester using the digging platform as a digging device. By monitoring the posture of the digging device at the front end of the harvester, a control system is used in conjunction with monitoring data to determine the soil entry angle of the rotary tillage device and the posture during tillage, so as to achieve controllable digging depth during the harvesting process and ensure the digging quality.

[0004] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions.

[0005] A floating cyperus oleifera digging platform comprises a frame, a rotary tillage assembly is installed at the front end of the frame, a lifting screen located behind the rotary tillage assembly is installed in the middle of the frame, and a hinge seat is installed at the upper rear end of the frame for being hinged to the front end of the body of the harvester; the front end of the hydraulic cylinder hinged to the body is hinged to the lower rear side of the frame for adjusting the height of the rotary tillage assembly by telescoping the hydraulic cylinder; a driving motor is installed on the frame, and the output shaft of the driving motor is connected with a first chain transmission mechanism and a second chain transmission mechanism, the first chain transmission mechanism is connected with the transmission shaft at the rear end of the lifting screen for driving the transport network chain of the lifting screen to circulate; the second chain transmission mechanism is connected with the driving wheel of the belt transmission mechanism fixed to the frame, and the driven wheel of the belt transmission mechanism is connected with the rotary tillage assembly for driving the rotary tillage blade of the rotary tillage assembly to rotate; an angle sensor is installed on the frame for detecting the swing angle of the frame around the hinge seat; a displacement sensor is installed on the frame for detecting the horizontal offset of the frame.

[0006] As a further optimization, the rotary tilling assembly includes a rotary tilling shaft connected to the driven wheel, and a plurality of rotary tilling blades are connected to the rotary tilling shaft; a soil feed shovel is fixedly connected to the frame and is located between the rotary tilling blade and the lifting screen, and is used to scoop up the bean-soil mixture crushed by the rotary tilling blade and transport it to the lifting screen; the soil gathering outer shell cover is buckled on the outside of the rotary tilling blade, and baffles are provided on both sides thereof, and the two baffles are sealed and fixedly connected to the two ends of the soil feed shovel, and are used to gather the bean-soil mixture within the scooping range of the soil feed shovel.

[0007] As a further optimization, the multiple rotary tillers are divided into multiple pairs and are evenly spaced in the axial direction of the rotary tiller shaft; each pair of rotary tillers is distributed at 180° on the vertical section of the rotary tiller shaft, and each axially adjacent pair of rotary tillers form an angle of 60°; the blade heads of the rotary tillers have a bending angle of 120°, and the bending directions of the blade heads of each pair of rotary tillers are opposite.

[0008] As a further optimization, the transport network chain includes a plurality of chain plates connected at the ends; each of the chain plate bodies is L-shaped, including a chain plate bottom plate and a chain plate vertical plate fixedly connected to one side of the chain plate bottom plate; densely distributed long strip sieve holes are provided on the chain plate bottom plate for screening out soil from the bean-soil mixture on the lifting screen.

[0009] As a further optimization, the lifting screen also includes a vibration shaft located in the middle of the conveying network chain, the vibration shaft is installed on the frame, and is connected to the transmission shaft for synchronous rotation when the conveying network chain rotates in a cycle; a triangular support plate is connected to the vibration shaft for driving the conveying network chain to vibrate up and down when the vibration shaft rotates.

[0010] The present invention also provides a cyperus oleifera harvester, comprising the floating cyperus oleifera digging platform as described above.

[0011] As a further optimization, the center of the articulated seat and the hinge point of the hydraulic cylinder on the machine body are in the same vertical plane; and the control device of the hydraulic cylinder is arranged on the machine body for controlling the extension and retraction of the hydraulic cylinder.

[0012] The present invention also provides a control method for a floating cyperus oleiferus digging platform, using the cyperus oleiferus harvester as described above, comprising the following steps:

[0013] S1: Set the initial position; the position where the lower end of the rotary tillage assembly rests on the ground is the initial position; at this time, the digging depth is zero, the center position of the articulated seat is marked as point A, the hinge point of the hydraulic cylinder on the machine body is marked as point B, the hinge point of the hydraulic cylinder on the frame is marked as point O, and the axis of the rotary tillage assembly is marked as point C; the angle between OA and OB is θ.

[0014] S2: Setting an initial excavation depth h; controlling the extension and contraction amount ΔL of the hydraulic cylinder so that the point C reaches the excavation depth h; wherein ΔL is calculated by formula (5).

[0015] Formula (5); wherein, when point C reaches the digging depth h, the hinge point of the hydraulic cylinder on the frame is marked as O ’ Point, the axis of the rotary tillage assembly is marked as C ’ point, I will O ’ A and O ’ The angle between B.

[0016] S3: Start digging for Cyperus oleifera and collect the angle in real time through the angle sensor I will The value of the acquisition frequency is 5s, and the accuracy is not less than 0.5°; when the angle I will When the fluctuation range reaches a preset fluctuation angle, the control device of the hydraulic cylinder is started to correct so that the excavation depth is restored to h.

[0017] As a further optimization, stiffness trimming is also included to correct the ΔL in step S2; the corrected ΔL ’ Calculate according to formula (9).

[0018] Formula (9); where m is the stiffness variation coefficient of line segment OA.

[0019] As a further optimization, the fluctuation angle in step S3 is set as follows. i Digging depthh The normalized sensitivity S is set; S is calculated according to formula (10).

[0020] Formula (10); When 0<S≤0.05, the fluctuation angle is ±4°; when 0.05<S≤0.2, the fluctuation angle is ±3°; when 0.2<S≤1, the fluctuation angle is ±2°; when S>1, the fluctuation angle is ±1°; where, β It is the mechanical inherent angle between line segment AC and line segment OA.

[0021] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention sets the cyperus rotundus digging platform in a floating manner at the front end of the harvester, can accurately control the digging depth, reduce the amount of digging when digging cyperus rotundus, reduce fuel consumption, and also reduce the burden of soil screening on the subsequent mechanism of the harvester, and has a strong soil screening ability. Compared with the traditional cyperus rotundus digging device, it can greatly reduce the soil content delivered to the harvester's cleaning mechanism, and improve the efficiency and quality of cyperus rotundus harvesting. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the present invention.

[0023] Figure 2 It is a schematic structural diagram of a rotary tillage assembly according to an embodiment of the present invention.

[0024] Figure 3 It is a schematic structural diagram of a harvester according to an embodiment of the present invention.

[0025] Figure 4 The figure is a diagram showing the lifting working principle of the rotary tillage mechanism according to an embodiment of the present invention.

[0026] Figure 5 Parameter sensitivity classification table of an embodiment of the present invention.

[0027] In the figure: 1. frame; 2. rotary tillage assembly; 3. lifting screen; 4. lifting arm; 5. support rod; 6. articulated seat; 7. triangular support seat; 8. hydraulic cylinder; 9. hinge point B; 10. angle sensor; 11. displacement sensor; 12. rotary tillage blade; 13. rotary tillage shaft; 14. soil feed shovel; 15. soil gathering shell; 100. harvester body; 200. cyperus oleifera digging platform. DETAILED DESCRIPTION

[0028] The present invention is described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only some preferred embodiments of the present invention, rather than all embodiments. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0029] Example: See Figure 1-5 .

[0030] The present invention proposes a floating cyperus oleifera digging platform, which is installed at the front end of the harvester. The frame 1 is the main structure of the front end device of the harvester, and the rotary tillage assembly 2 and the lifting screen 3 are reliably connected. The lifting arm 4 and the support rod 5 are installed on the rear side of the frame 1, and are connected to the vertical wall on the rear end harvester body through the hinge seat 6. This structure can ensure that the front end device (rotary tillage assembly 2 and lifting screen 3) is stably and reliably lifted. The triangular support seat 7 at the center of the lifting arm 4 is connected to one end of the driving hydraulic cylinder 8, and the other end of the hydraulic cylinder 8 is fixed to the vertical wall through the hinge point. The component is driven by the electronic control system and can apply thrust or pulling force to the lifting arm 4, thereby driving the front end device to lift or lower. In addition, an angle sensor 10 is installed on one side of the lifting arm 4 near the hinge seat 6, which is used to monitor the angle between the lifting arm 4 and the vertical wall of the harvester body in real time. A displacement sensor 11 is installed on one side of the frame 1, which is used to monitor the horizontal displacement of the front end device of the harvester in real time when the harvester is moving.

[0031] The front side of the frame 1 is connected to the rotary tillage assembly 2, which includes a rotary tillage blade 12, a rotary tillage shaft 13, a soil shovel 14 and a soil collecting shell 15. The entire rotary tillage device is equipped with fourteen pairs of rotary tillage blades 12, and each pair of rotary tillage blades 12 is distributed at 180° on the vertical section of the rotating shaft. The heads of the rotary tillage blades 12 have a bending angle of 120°, and the bending direction is that the blade heads of each pair of rotary tillage blades 12 are dispersed and bent to both sides. When designed, the fourteen pairs of rotary tillage blades 12 are evenly installed on the rotary tillage shaft 13, and the adjacent pairs of rotary tillage blades 12 form an angle of 60°. In addition, the excavation area of ​​the adjacent interval rotary tillage blades 12 during the rotation process is smaller than the interval distance. This is because considering that the current planting environment of most cyperus oleifera is sandy land, the soil is relatively loose and has low viscosity. When the rotary tillage blades 12 are in operation, due to the bending design of the heads of the rotary tillage blades 12 and the high-speed rotation, the blades will generate lateral extrusion force after contacting the soil. Although there is an un-tilled area between two adjacent groups of rotary tilling blades 12, the extrusion force from both sides will still cause the soil in the middle un-tilled position to be broken, and the rotary tillage effect has been achieved. Such a design can reduce the consumables in the equipment manufacturing process and the power energy consumption in the use process. Due to the high-speed rotation of the cutter and the extrusion of the soil shovel 14 during the rotary tillage process, the broken bean-soil mixture will splash or scatter to both sides of the harvester's travel direction, which will affect the quality of the harvesting operation and increase the fruit leakage rate. In order to avoid the occurrence of this situation, a soil-collecting shell 15 is installed on the outside of the rotary tillage device. On the one hand, it is ensured that the rotary tillage and broken bean-soil mixture is transported to the rear end by the soil shovel 14 as much as possible, and on the other hand, it is prevented that the splashed debris enters the transmission device, damages the power mechanism, and reduces the service life of the harvester. The transmission device of the rotary tillage mechanism is installed on the right side of the rotary tillage shaft 13, is connected to the differential at the upper end, and is used to drive the rotary tillage blade 12 to rotate counterclockwise at high speed.

[0032] The lifting screen 3 is installed in the middle position of the frame 1, which includes a transport network chain, a vibration shaft, and a transmission device. The transport network chain is composed of a plurality of long perforated screen plates, and the transmission device is connected at both ends. The drive motor or hydraulic motor can drive the transport network chain to rotate clockwise and upward in a circular manner, so as to transport the bean-soil mixture excavated by the rotary tillage device to the rear end of the device. The vibration shaft is respectively installed in the middle position of the front end and the rear end of the transport network chain, and is connected to the drive motor or hydraulic motor through the transmission device. When the drive motor or hydraulic motor is in operation, in addition to driving the transport network chain to rotate clockwise, it also causes the two vibration shafts to rotate clockwise. Due to the presence of irregular triangular support plates at both ends of the vibration shaft, the transport network chain can vibrate up and down during the rotation process. When the bean-soil mixture moves upward with the rotation of the transport network chain, the perforated screen plate can initially screen out some debris such as soil blocks, and then the screen plate formed by the rotation of the vibration shaft oscillates up and down, and more sand or broken straw is separated, completing the first stage screening of the harvested material, reducing the amount of soil entering the rear of the harvester, and reducing the cleaning load of the subsequent device.

[0033] According to the design structure of the front-end device of the harvester, a monitoring unit and a control device are installed on the right side of the frame 1 connected to the position of the harvester body. Since the digging depth of the rotary tillage device is closely related to the working posture of the front-end device, on the basis of analyzing the movement process of the front-end device, the direct relationship between the real-time digging depth of the rotary tillage blades 12 pairs and the collected posture angle of the lifting arm 4 is obtained, and a digging depth calculation model is established to provide data support for the control system at the back end. From the connection structure between the front-end device and the harvester, it can be seen that the lifting and lowering of the front-end device mainly rely on the lifting arm 4 and the hydraulic cylinder 8, and other steel frame structures play a supporting and fixing role. Based on this, the design structure of the front-end device can be simplified for analyzing its movement process, such as Figure 4 shown.

[0034] Figure 4 The diagram is a diagram of the lifting working principle of the rotary tillage mechanism, where point O is the triangular support seat 7 at the center of the lifting arm 4, and points A and B are the hinge points of the lifting arm 4 and the hydraulic cylinder 8 on the vertical fixed surface of the harvester, that is, the center of the hinge seat is point A, and the hinge point B9 at the rear end of the hydraulic cylinder 8 is on the body of the harvester. Point C is the center point of the rotation axis of the rotary tillage device. When the rotary tillage device is lifted or lowered, the hydraulic cylinder 8 provides a driving force to control the length of the line segment OB so that the front end device rotates around the hinge point A. As can be seen from the figure, C' is the position of the center point of the rotation axis of the rotary tillage device after the descent. At this time, the rotation of the lifting arm 4 changes its angle with the vertical fixed surface. i , which can be used to determine the height of the rotary tillage device's rotating shaft center point h Perform modeling calculations, including formulas (1-4).

[0035] Formula (1).

[0036] Formula (2).

[0037] Formula (3).

[0038] Formula (4).

[0039] Where: h The digging depth of the rotary tillage device; l AC The distance between the center point C of the rotary tillage device and the hinge point A; f is the angle between line segment AC and the vertical fixed wall; l OC The distance between the center point C of the rotary tillage device and the triangular support seat 7 O; l OA is the distance between the triangular support seat 7 O and the hinge point A; α It is the mechanical inherent angle between the line connecting the rotary axis of the rotary tillage device and the triangular support seat 7 and the lifting arm 4; β is the mechanical inherent angle between line segment AC and line segment OA; i Angle monitoring for the sensor.

[0040] When the actual excavation depth is h, the contraction amount of the hydraulic cylinder 8 is ΔL; Formula (5).

[0041] Considering that the front-end structure of the harvester will inevitably deform during actual operation, this will lead to a、b、l OA 、l OC Parameters such as the depth of the excavation will change, which will cause errors in the calculated excavation depth data. It is necessary to introduce a correction coefficient into the model to compensate for the impact of the error.

[0042] Formula (6). Where: k is the error correction coefficient caused by structural deformation, k With the model α、l OA 、l OC The change in α、l OA 、l OC The coefficients of variation are z, m, and n respectively.

[0043] Formula (7).

[0044] Formula (8).

[0045] The actual contraction amount of the hydraulic cylinder 8 is: Formula (9); where m is the stiffness variation coefficient of line segment OA.

[0046] From the model, we can see that as long as we monitor i The digging depth of the rotary tillage device can be obtained by changing the angle of the rotary tillage device. i Then, determine the appropriate digging depth based on the growth depth characteristics of the cyperus oleifera plant. h , and use the excavation depth calculation model to obtain the I will During the operation, the electronic control system is used to control the hydraulic cylinder 8 to achieve the angle i The angle sensor 10 collects the changes in the angle between the lifting arm 4 and the vertical fixed surface in real time, with a collection frequency of 5s and an accuracy of 0.5°. The control device stops the angle information between the lifting arm 4 and the vertical fixed surface when the required angle is reached. Due to the influence of factors such as ground conditions, vehicle conditions and human factors during operation, the angle between the lifting arm 4 and the vertical fixed surface i may change, and a feedback mechanism needs to be set to correct the digging depth of the rotary tillage device in real time, that is, when the angle i When the fluctuation range reaches a certain angle, the control device is started to correct the collected angle information. This fluctuation angle can be adjusted according to the monitoring angle. i Digging depth h The normalized sensitivity S is set according to the actual operation requirements for the depth of excavation, combined with the monitoring angle i Change the digging depth h According to the sensitivity of the impact, select the appropriate fluctuation angle to achieve accurate control of the excavation depth quality. Figure 5 To be graded. Figure 5 This is a parameter sensitivity grading table.

[0047] Formula (10).

[0048] Similarly, in order to solve the linear stability problem of the harvester operation path, multiple displacement sensors 11 are used to monitor the horizontal displacement of the side wall of the frame 1 and the rotation displacement of the tractor front wheel. According to the multiple displacements monitored in real time, the straight driving state of the harvester is comprehensively judged. When the displacement exceeds a certain value, it is fed back to the direction control system, so as to quickly adjust the vehicle operation state in real time.

[0049] It can be seen that the floating cyperus oleifera digging platform of the present invention comprises a rotary tillage assembly 2 installed at the front end of the frame 1, a lifting screen 3 located behind the rotary tillage assembly 2 is installed in the middle of the frame 1, and an articulated seat 6 is installed at the upper rear end of the frame 1 for articulating with the front end of the harvester body; the front end of the hydraulic cylinder 8 articulated with the body is articulated at the lower rear side of the frame 1 for adjusting the height of the rotary tillage assembly 2 by telescoping the hydraulic cylinder 8; a hydraulic motor is installed on the frame 1, and the output shaft of the hydraulic motor is connected to the first chain transmission mechanism and the second chain transmission mechanism The first chain transmission mechanism is connected to the transmission shaft at the rear end of the lifting screen 3, and is used to drive the transport network chain of the lifting screen 3 to circulate; the second chain transmission mechanism is connected to the driving wheel of the belt transmission mechanism fixed to the frame 1, and the driven wheel of the belt transmission mechanism is connected to the rotary tillage component 2, and is used to drive the rotary tillage blade 12 of the rotary tillage component 2 to rotate; an angle sensor 10 is installed on the frame 1, which is used to detect the swing angle of the frame 1 around the articulated seat 6; a displacement sensor 11 is installed on the frame 1, which is used to detect the horizontal offset of the frame 1.

[0050] A preferred implementation of the rotary tilling assembly 2 is that the rotary tilling assembly 2 includes a rotary tilling shaft 13 connected to the driven wheel, and a plurality of rotary tilling blades 12 are connected to the rotary tilling shaft 13; a soil feed shovel 14 is fixedly connected to the frame 1 and is located between the rotary tilling blades 12 and the lifting screen 3, and is used to scoop up the bean-soil mixture crushed by the rotary tilling blades 12 and transport it to the lifting screen 3; a soil gathering shell 15 is buckled on the outside of the rotary tilling blades 12, and baffles are provided on both sides thereof, and the two baffles are sealed and fixedly connected to the two ends of the soil feed shovel 14, and are used to gather the bean-soil mixture within the scooping range of the soil feed shovel 14.

[0051] In order to improve the excavation effect and reduce the excavation resistance, the multiple rotary tillers 12 are divided into multiple pairs and are evenly spaced in the axial direction of the rotary tiller shaft 13; each pair of rotary tillers 12 is distributed at 180° on the vertical section of the rotary tiller shaft 13, and each axially adjacent pair of rotary tillers 12 form an angle of 60°; the blade heads of the rotary tillers 12 have a bending angle of 120°, and the bending directions of the blade heads of each pair of rotary tillers 12 are opposite.

[0052] The preferred embodiment of the lifting screen 3 is that the transporting network chain includes a plurality of chain plates connected at the end; each of the chain plates is L-shaped, including a chain plate bottom plate and a chain plate vertical plate fixedly connected to one side of the chain plate bottom plate; the chain plate bottom plate is provided with densely distributed long strip sieve holes for screening out the soil in the bean-soil mixture on the lifting screen 3. The chain plate bottom plate with sieve holes is used to screen the soil and retain the beans, and the vertical chain plate vertical plate is used to provide lifting force for the bean-soil mixture.

[0053] In order to improve the effect of screening soil, the lifting screen 3 also includes a vibration shaft located in the middle of the transport network chain, the vibration shaft is installed on the frame 1, and is connected to the transmission shaft, so that when the transport network chain rotates in a cycle, the vibration shaft rotates synchronously; a triangular support plate is connected to the vibration shaft, so that when the vibration shaft rotates, the transport network chain is driven to vibrate up and down. The transport network chain that vibrates up and down can first promote the separation of beans and soil, secondly, it can promote the rapid passage of soil particles through the sieve holes to avoid blockage, and thirdly, it can promote the crushing of large soil blocks, so that more soil particles can be screened out.

[0054] When the floating cyperus oleifera digging platform is applied to a self-propelled harvester, Figure 3 As shown, the cyperus oleifera digging platform 200 is connected to the front end of the harvester body 100. The center of the articulated seat 6 and the hinge point of the hydraulic cylinder 8 on the body are in the same vertical plane; the control device of the hydraulic cylinder 8 is arranged on the body to control the extension and retraction of the hydraulic cylinder 8.

[0055] The precise control of the stroke of the hydraulic cylinder can be achieved in the following ways. First, proportional valve control: the stroke of the hydraulic cylinder can be controlled by adjusting the opening of the proportional valve. The proportional valve can accurately control the stroke of the hydraulic cylinder according to the size of the input signal. Second, servo valve control: the servo valve is a valve that can accurately control the stroke of the hydraulic cylinder according to the input signal. By adjusting the opening of the servo valve, the precise control of the stroke of the hydraulic cylinder can be achieved. Third, position sensor feedback control: installing a position sensor on the hydraulic cylinder can monitor the stroke of the hydraulic cylinder in real time and feed back the stroke information to the control system. The control system can accurately control the stroke of the hydraulic cylinder according to the feedback information so that the stroke of the hydraulic cylinder reaches the predetermined position. Fourth, a closed-loop control system is used: the closed-loop control system can accurately control the stroke of the hydraulic cylinder by controlling the opening of the actuator (such as a proportional valve or a servo valve) according to the difference between the set value and the feedback value. The closed-loop control system can be adjusted according to the actual situation to achieve a more precise control effect. In short, the stroke control of the hydraulic cylinder can be precisely controlled by proportional valves, servo valves, position sensor feedback and closed-loop control systems. The specific method to be selected needs to be determined based on actual application needs and control requirements.

[0056] This embodiment includes the following steps when used.

[0057] S1: Set the initial position; the position where the lower end of the rotary tillage component 2 is against the ground is the initial position; at this time, the digging depth is zero, the center position of the articulated seat 6 is marked as point A, the hinge point of the hydraulic cylinder 8 on the machine body is marked as point B, the hinge point of the hydraulic cylinder 8 on the frame 1 is marked as point O, and the axis of the rotary tillage component 2 is marked as point C; the angle between OA and OB is θ.

[0058] S2: Setting an initial excavation depth h; controlling the extension and contraction amount ΔL of the hydraulic cylinder 8 so that the point C reaches the excavation depth h; wherein ΔL is calculated by formula (5).

[0059] Formula (5). When point C reaches the digging depth h, the hinge point of the hydraulic cylinder 8 on the frame 1 is marked as O ’ Point, the axis of the rotary tillage assembly 2 is marked as C ’ point, I will O ’ A and O ’ The angle between B.

[0060] S3: Start digging for cyperus oleifera and collect the angle in real time through the angle sensor 10 I will The value of the acquisition frequency is 5s, and the accuracy is not less than 0.5°; when the angle I will When the fluctuation range reaches the preset fluctuation angle, the control device of the hydraulic cylinder 8 is started to correct so that the excavation depth is restored to h.

[0061] As a further optimization, stiffness trimming is also included to correct the ΔL in step S2; the corrected ΔL ’ Calculate according to formula (9); Formula (9); where m is the stiffness variation coefficient of line segment OA.

[0062] As a further optimization, according to the angle i Digging depth h The normalized sensitivity S is set; S is calculated according to formula (10).

[0063] Formula (10); When 0<S≤0.05, the fluctuation angle is ±4°; when 0.05<S≤0.2, the fluctuation angle is ±3°; when 0.2<S≤1, the fluctuation angle is ±2°; when S>1, the fluctuation angle is ±1°; where, β It is the mechanical inherent angle between line segment AC and line segment OA.

[0064] Through graded control of sensitivity, on the basis of ensuring precise control of the excavation depth, excessive and frequent extension and retraction of the hydraulic cylinder 8 can be avoided, the working frequency of the hydraulic components can be reduced, and their service life can be protected.

[0065] In summary, the present embodiment sets the cyperus rotundus digging platform in a floating manner at the front end of the harvester, which can accurately control the digging depth, reduce the amount of soil excavation when digging cyperus rotundus, reduce fuel consumption, and also reduce the burden of soil screening on the subsequent mechanisms of the harvester. It has a strong soil screening ability. Compared with the traditional cyperus rotundus digging device, it can greatly reduce the soil content delivered to the harvester's cleaning mechanism, and improve the efficiency and quality of cyperus rotundus harvesting.

[0066] The parts of the present invention that are not described in detail are prior art. For ordinary technicians in this field, the technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

Claims

1. A floating cyperus oleifera digging platform, comprising a frame (1), characterized in that: A rotary tillage assembly (2) is installed at the front end of the frame (1); a lifting screen (3) located behind the rotary tillage assembly (2) is installed in the middle of the frame (1); an articulated seat (6) is installed at the upper rear end of the frame (1) for articulating with the front end of the harvester body; the front end of a hydraulic cylinder (8) articulated with the body is articulated at the lower rear side of the frame (1); The frame (1) is provided with a driving motor, the output shaft of the driving motor being connected to a first chain transmission mechanism and a second chain transmission mechanism; the first chain transmission mechanism is connected to a transmission shaft at a rear end of the lifting screen (3) and is used to drive a conveying net chain of the lifting screen (3) to circulate; the second chain transmission mechanism is connected to a driving wheel of a belt transmission mechanism fixed to the frame (1), and a driven wheel of the belt transmission mechanism is connected to the rotary tillage assembly (2) and is used to drive a rotary tillage blade (12) of the rotary tillage assembly (2) to rotate; An angle sensor (10) is installed on the frame (1) for detecting the swing angle of the frame (1) around the hinge seat (6); and a displacement sensor (11) is installed on the frame (1) for detecting the horizontal offset of the frame (1).

2. The floating cyperus oleifera digging platform according to claim 1, characterized in that: The rotary tillage assembly (2) comprises a rotary tillage shaft (13) connected to the driven wheel, and a plurality of rotary tillage blades (12) are connected to the rotary tillage shaft (13); a soil feed shovel (14) is fixedly connected to the frame (1) and is located between the rotary tillage blades (12) and the lifting screen (3), and is used to scoop up the bean-soil mixture crushed by the rotary tillage blades (12) and transport it to the lifting screen (3); a soil collecting shell (15) is buckled on the outside of the rotary tillage blades (12), and baffles are provided on both sides of the shell, and the two baffles are sealed and fixedly connected to the two ends of the soil feed shovel (14), and are used to gather the bean-soil mixture within the scooping range of the soil feed shovel (14).

3. The floating cyperus oleifera digging platform according to claim 2, characterized in that: The plurality of rotary tilling blades (12) are divided into a plurality of pairs and are evenly spaced in the axial direction of the rotary tilling shaft (13); each pair of rotary tilling blades (12) are distributed at 180° on a vertical section of the rotary tilling shaft (13), and each pair of axially adjacent rotary tilling blades (12) form an angle of 60°; the blade heads of the rotary tilling blades (12) have a bending angle of 120°, and the bending directions of the blade heads of each pair of rotary tilling blades (12) are opposite.

4. The floating cyperus oleifera digging platform according to claim 1, characterized in that: The transport network chain includes a plurality of chain plates connected at the ends; each chain plate body is L-shaped, including a chain plate bottom plate and a chain plate vertical plate fixedly connected to one side of the chain plate bottom plate; and densely distributed long strip sieve holes are provided on the chain plate bottom plate.

5. The floating cyperus oleifera digging platform according to claim 4, characterized in that: The lifting screen (3) also includes a vibration shaft located in the middle of the conveying network chain, the vibration shaft is installed on the frame (1) and is connected to the transmission shaft for synchronous rotation when the conveying network chain rotates in a circular motion; a triangular support plate is connected to the vibration shaft for driving the conveying network chain to vibrate up and down when the vibration shaft rotates.

6. A cyperus oleifera harvester, characterized in that: The invention comprises a floating cyperus oleifera digging platform as claimed in any one of claims 1 to 5.

7. The cyperus oleifera harvester according to claim 6, characterized in that: The center of the hinge seat (6) and the hinge point of the hydraulic cylinder (8) on the machine body are in the same vertical plane; and a control device of the hydraulic cylinder (8) is arranged on the machine body and is used to control the extension and retraction of the hydraulic cylinder (8).

8. A method for controlling a floating cyperus oleifera digging platform, characterized in that: The method of using the cyperus oleifera harvester as claimed in claim 7 comprises the following steps: S1: setting the initial position; the position where the lower end of the rotary tillage assembly (2) is against the ground is taken as the initial position; at this time, the digging depth is zero, the center position of the articulated seat (6) is marked as point A, the hinge point of the hydraulic cylinder (8) on the machine body is marked as point B, the hinge point of the hydraulic cylinder (8) on the frame (1) is marked as point O, and the axis of the rotary tillage assembly (2) is marked as point C; the angle between OA and OB is θ; S2: setting an initial excavation depth h; controlling the extension and contraction amount ΔL of the hydraulic cylinder (8) so that the point C reaches the excavation depth h; wherein ΔL is calculated by formula (5); Formula (5): When point C reaches the excavation depth h, the hinge point of the hydraulic cylinder (8) on the frame (1) is marked as O. ’ The axis of the rotary tillage assembly (2) is marked as C. ’ point, θ' O ’ A and O ’ The angle between B; S3: Start digging for cyperus oleifera and collect the angle in real time through the angle sensor (10) θ' The value of the acquisition frequency is 5s, and the accuracy is not less than 0.5°; when the angle θ' When the fluctuation range reaches a preset fluctuation angle, the control device of the hydraulic cylinder (8) is started to make corrections so that the excavation depth is restored to h.

9. The control method of the floating cyperus oleifera digging platform according to claim 8, characterized in that: It also includes stiffness trimming, which is to correct the ΔL in step S2; the corrected ΔL ’ Calculate according to formula (9); Formula (9): Where m is the stiffness variation coefficient of line segment OA.

10. The control method of the floating cyperus oleifera digging platform according to claim 8, characterized in that: The fluctuation angle in step S3 is set as follows: According to the angle θ Digging depth h The normalized sensitivity S is set; S is calculated according to formula (10); Formula (10): When 0<S≤0.05, the fluctuation angle is ±4°; when 0.05<S≤0.2, the fluctuation angle is ±3°; when 0.2<S≤1, the fluctuation angle is ±2°; when S>1, the fluctuation angle is ±1°; where, β It is the mechanical inherent angle between line segment AC and line segment OA.

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