An intelligent lettuce leaf-removing harvester

Abstract

The present invention discloses an intelligent lettuce defoliating harvester, which belongs to a harvester in the technical field of agricultural machinery and equipment. Its technical solution includes: a vehicle frame, and a walking wheel assembly is arranged at the bottom of the vehicle frame; a harvesting conveyor device, which is arranged at the front end in the walking direction of the vehicle frame and is used for cutting and conveying lettuce; a defoliating treatment device, which is arranged at the upper end of the vehicle frame and is connected to the conveying end of the harvesting conveyor device for defoliating treatment of lettuce; the defoliating treatment device includes a defoliating conveyor belt arranged above the harvesting conveyor device and a lifting conveyor belt arranged below the defoliating conveyor belt; The present invention provides an intelligent lettuce defoliating harvester. Through the movement control of the vehicle frame by the walking wheel assembly, the mutual cooperation between the harvesting conveyor device and the defoliating treatment device is realized, so as to perform operations such as defoliating and conveying after cutting the lettuce, improve the intelligent and automated level of agricultural production and save costs, thereby improving production efficiency.

Description

Technical Field

[0001] The present invention belongs to the technical field of agricultural machinery and equipment, and particularly relates to an intelligent lettuce leaf-removing harvester. Background Art

[0002] At present, lettuce is a widely planted and consumed vegetable, playing an important role globally. With the continuous advancement of agricultural modernization and the improvement of agricultural mechanization level, the planting scale of lettuce has gradually expanded, so the demand for lettuce harvesters is also increasing day by day. The traditional manual harvesting method is inefficient, labor-intensive, and the leaf-removing process is cumbersome, unable to meet the needs of modern agriculture. The research and development of lettuce harvesters emerged as the times require and became an important tool to improve production efficiency and save labor costs.

[0003] In recent years, mechanized operations have been implemented for the cultivated land and transplanting work of lettuce planting in China, but the research on the harvesting mechanization technology for vegetables such as lettuce in China is still continuously carried out and improved. Although the existing equipment has solved a large number of problems in the mechanized harvesting of lettuce in China, it still relies on other agricultural machinery and its lettuce leaf-removing function has not been perfected and is not fully intelligent. Therefore, the machine that urgently needs to be studied is to achieve the full intelligence of lettuce harvesting.

[0004] The construction of agricultural mechanization and intelligence in China has received much attention, covering the following aspects:

[0005] I. Automation and Intelligence: Some companies such as Zoomlion Heavy Industry Science & Technology Co., Ltd., YTO (Luoyang) Agricultural Equipment Co., Ltd. focus on the development of automatic navigation, intelligent recognition, and adaptive control technologies to improve the harvesting efficiency and reduce labor costs.

[0006] II. Multifunction and Integration: Companies such as Jiangsu Century Sunshine Group, Shenyang Agricultural Machinery Research Institute are committed to the research and development of S multifunctional vegetable harvesters, which can adapt to different crops and terrains, achieve multi-purpose use of one machine, and improve the equipment utilization rate.

[0007] III. Precision Agriculture Technology: Beijing Academy of Agricultural Intelligent Equipment, Zhejiang University, etc. carry out the use of Internet of Things, big data, and artificial intelligence technologies to achieve precise monitoring of the vegetable growth environment and accurate grasp of the harvesting time.

[0008] IV. Energy Conservation and Emission Reduction: Companies such as Golden Sun Agricultural Machinery Group, Lovol Heavy Industry Co., Ltd. are committed to the development of energy-saving vegetable harvesters to reduce energy consumption and emissions and respond to the national energy conservation and emission reduction policy.

[0009] V. Human-Machine Interaction: Companies such as Zhejiang Yuhuan Numerical Control Machinery Co., Ltd. are committed to improving the operation interface, enhancing the user experience, making the operation more convenient, and reducing the labor intensity of the operator.

[0010] Based on the above advantages and disadvantages, the project of lettuce harvester was designed and developed. Summary of the Invention

[0011] The object of the present invention is to provide an intelligent lettuce defoliating harvester. Through the motion control of the frame by the walking wheel assembly, the mutual cooperation between the harvesting and conveying device and the defoliating treatment device is realized, so as to realize operations such as cutting and defoliating and conveying of lettuce, improve the intelligent and automated level of high agricultural production, save costs, and thus improve production efficiency.

[0012] The object of the present invention is achieved as follows. An intelligent lettuce defoliating harvester includes:

[0013] A frame, with a walking wheel assembly arranged at the bottom of the frame;

[0014] A harvesting and conveying device, arranged at the front end in the walking direction of the frame, for cutting and conveying lettuce;

[0015] A defoliating treatment device, arranged at the upper end of the frame and connected to the conveying end of the harvesting and conveying device, for defoliating treatment of lettuce; and,

[0016] The defoliating treatment device includes a defoliating conveyor belt arranged above the harvesting and conveying device and a lifting conveyor belt arranged below the defoliating conveyor belt. The cooperation of the defoliating plates in the defoliating conveyor belt and the lifting conveyor belt is used for lifting, squeezing and defoliating lettuce.

[0017] Further, the walking wheel assembly includes 4 independently driven walking wheels arranged at the bottom of the frame, forming differential drive for the walking and turning of the frame.

[0018] Further, the harvesting and conveying device includes a cutting tool fixedly arranged at the bottom of the frame and a clamping conveyor belt arranged above the cutting tool. The clamping conveyor belt is arranged obliquely upward or horizontally along the conveying direction; the cutting tool includes two disc blade groups, and the disc-shaped blades in the two disc blade groups are horizontally adjacent and cooperatively arranged; the front end of the clamping conveyor belt is placed above the front of the two disc blade groups.

[0019] Further, the clamping conveyor belt includes two parallel conveyor belt units. The conveyor belt unit includes a vertically arranged conveyor belt and a power source for driving the conveyor belt. A plurality of flexible clamping strips are arranged in the width direction of the outer surface of the conveyor belt, and the plurality of flexible clamping strips are evenly distributed in the length direction of the conveyor belt; the two power sources rotate in reverse synchronously for the clamping conveyor belt to convey towards the inside of the frame.

[0020] Further, the defoliating conveyor belt includes two stripping conveyor track units arranged in parallel along the conveying direction and the defoliating plate. The stripping conveyor track unit includes a track motor vertically fixed on the vehicle frame and a stripping conveyor track rotatably connected to the track motor. A plurality of clamping heads are arranged on the outer surface of the stripping conveyor track, and the plurality of clamping heads are evenly distributed in the length direction of the stripping conveyor track; the two track motors rotate in reverse synchronously for conveying the defoliating conveyor belt to the outside of the vehicle frame.

[0021] Further, the lifting conveyor belt includes a supporting conveyor belt and a driving roller shaft group. The driving roller shaft group is inclinedly arranged on the vehicle frame and is driven by a conveying motor fixedly arranged on the vehicle frame; a plurality of transverse rods are arranged on the outer surface of the supporting conveyor belt, the transverse rods are arranged in the width direction of the supporting conveyor belt, and the plurality of transverse rods are evenly distributed in the length direction of the supporting conveyor belt.

[0022] Further, a storage container is arranged on the vehicle frame, and the storage container is arranged directly below the output end of the lifting conveyor belt.

[0023] Further, the end of the stripping conveyor track is coaxially connected to the end adjacent to the driving conveyor belt, and the conveying speeds of the clamping conveyor belt, the defoliating conveyor belt and the lifting conveyor belt are the same.

[0024] Further, the clamping conveyor belt is inclinedly arranged, and its inclination angle is 20°.

[0025] Further, the storage container is detachably arranged on the vehicle frame, and a pressure sensor and a buzzer are electrically connected in the storage container.

[0026] The beneficial effects of the present invention are embodied in:

[0027] 1. In the present invention, the movement of the vehicle frame is controlled by setting the walking wheel assembly, so that the harvesting conveyor device on the vehicle frame can cut and convey the lettuce, and convey the cut lettuce to the defoliating device for defoliation operation; further, under the cooperation of the lifting conveyor belt and the defoliating conveyor belt, the cut lettuce is conveyed in a lifting manner, and during the lifting process of the lettuce, upward extrusion is realized under the guiding and conveying of the defoliating conveyor belt, and the old leaves on the side wall of the lettuce fall off under the action of the corresponding blocking members, so as to remove the old leaves of the lettuce. The operation of the whole device on the lettuce has the functions of integration and automation, greatly improving the convenience of harvesting the lettuce.

[0028] 2. In the present invention, by providing 4 independently driven walking wheels in the walking wheel assembly, differential driving between the wheels can be achieved, and sliding friction is utilized to achieve a steering effect. Moreover, it is applicable to wild mountain terrains, compensating for the drawback that lettuce harvesting is restricted by terrain. The physical structure of a mechanical differential is eliminated, and only an electronic differential controller based on Ackermann steering for front-wheel steering needs to be designed. By coordinately controlling the rotational speeds of the four hub motors respectively, the rotational speeds of each wheel meet the requirements during turning, thereby achieving a steering purpose and greatly improving the efficiency of lettuce harvesting.

[0029] 3. In the present invention, by providing a cutting tool and a clamping conveyor belt above the cutting tool to cooperate, the cutting of lettuce is completed and it is conveyed to the leaf-removing device for waiting to have its leaves removed. When the lettuce is placed into the machine, the disk blade will cut it off. During this process, the lettuce moves forward while the disk blade cuts behind the lettuce. In the actual lettuce harvesting process, the disk cutting blade should cut the lettuce at an angle perpendicular or nearly perpendicular to the lettuce itself. This cutting method can ensure that the lettuce is evenly cut into the required flat cut surface, thereby facilitating subsequent conveying, leaf-removing operations, and storage and sorting.

[0030] 4. In the present invention, by providing two parallel conveyor belt units, the lettuce can be effectively output in a clamping manner. During the actual operation process, the clamping conveyor belt is arranged to slope upward, and the two power sources rotate in reverse synchronously, which can effectively convey the lettuce to a higher place. The design of the conveyor belt can better wrap and hold the lettuce, avoiding the situation of unstable clamping and tipping due to the problem of the vertical center of gravity height of the lettuce. Further, a plurality of flexible clamping strips are arranged in the width direction of the outer surface of the conveyor belt, strengthening the stability of the clamping of the lettuce.

[0031] 5. In the present invention, by providing the cooperation between two rejection conveyor track units and two leaf-removing plates, and making the distance between the two leaf-removing plates smaller than the distance between the two rejection conveyor track units, the two leaf-removing plates remove the old leaves of the clamped, guided, and rising lettuce below the two rejection conveyor track units. The plurality of clamping heads arranged on the outer surface of the rejection conveyor track strengthen the clamping stability effect of the lettuce. The setting of the two rejection conveyor track units can hold the lettuce to prevent it from tipping, and at the same time can also clamp the top of the lettuce to make it move up stably.

[0032] 6. In the present invention, by providing a lifting conveyor belt, the lettuce conveyed by the clamping conveyor belt is lifted and conveyed, so that the lettuce can be vertically guided and clamped in the two rejection conveyor track units above, and pass through between the two leaf-removing plates to remove the old leaves; further, a plurality of cross bars are provided on the outer surface of the support conveyor belt, and a card slot is formed between the two cross bars, which is beneficial to clamping the lettuce and preventing it from falling down under the action of gravity. Because the length of the lettuce is too long, the center of gravity is relatively high. The two rejection conveyor track units guide and clamp the upper end of the lettuce, and then apply a supporting force at its top to prevent it from falling down, which is convenient for stably removing the old leaves. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0034] Figure 1 Side view structural schematic diagram of the harvester of the present invention;

[0035] Figure 2 Top view structural schematic diagram of the harvester of the present invention;

[0036] Figure 3 Front view structural schematic diagram of the harvester of the present invention;

[0037] Figure 4 Simple working view of the walking wheel assembly of the present invention;

[0038] Figure 5 Schematic diagram of the speed analysis of the walking wheel assembly of the present invention;

[0039] Figure 6 Finite element analysis diagram of the disc-shaped blade of the present invention;

[0040] Figure 7 Force analysis diagram of the lettuce conveyance of the present invention.

[0041] In the attached drawings, 1 is the vehicle frame, 2 is the traveling wheel assembly, 3 is the harvesting conveyor device, 4 is the leaf-removing processing device, 5 is the leaf-removing conveyor belt, 6 is the lifting conveyor belt, 7 is the leaf-removing plate, 8 is the traveling wheel, 9 is the cutting tool, 10 is the clamping conveyor belt, 11 is the disc blade group, 12 is the disc-shaped blade, 13 is the conveyor belt, 15 is the flexible clamping strip, 16 is the rejection conveyor track unit, 17 is the leaf-removing plate, 18 is the rejection conveyor track, 19 is the clamping head, 20 is the track motor, 21 is the supporting conveyor belt, 22 is the driving roller shaft group, 23 is the conveyor motor, 24 is the cross bar, 25 is the storage container, 26 is the conveyor belt unit, 27 is the universal joint coupling. Detailed implementation manners

[0042] Hereinafter, embodiments of the technical solution of the present invention will be described in detail with reference to the attached drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, so they are only examples and cannot be used to limit the protection scope of the present invention.

[0043] It should be noted that unless otherwise specified, the technical terms or scientific terms used in this application should have the ordinary meanings understood by those skilled in the art to which the present invention belongs.

[0044] As Figures 1-7 shown, an intelligent lettuce leaf-removing harvester includes:

[0045] The vehicle frame 1, and the traveling wheel assembly 2 is arranged at the bottom of the vehicle frame 1;

[0046] The harvesting conveyor device 3, which is arranged at the front end in the traveling direction of the vehicle frame 1 and is used for cutting and conveying lettuce;

[0047] The leaf-removing processing device 4, which is arranged at the upper end of the vehicle frame 1 and is connected to the conveying end of the harvesting conveyor device 3, and is used for leaf-removing processing of lettuce; and,

[0048] The leaf-removing processing device 4 includes a leaf-removing conveyor belt 5 arranged above the harvesting conveyor device 3 and a lifting conveyor belt 6 arranged below the leaf-removing conveyor belt 5. The leaf-removing conveyor belt 5 and the lifting conveyor belt 6 cooperate in the conveyance of the leaf-removing plate 7 to lift, squeeze and remove the leaves of lettuce.

[0049] The function of the intelligent leaf-removing lettuce harvester is to realize the leaf-removing and harvesting of lettuce through the mutual cooperation between mechanical structures, greatly improving the harvesting efficiency of users, reducing a large amount of human resources, and making the harvesting of lettuce more mechanized and intelligent.

[0050] By setting the walking wheel assembly 2 to control the movement of the frame 1, the harvesting conveyor device 3 on the frame 1 can cut and convey the lettuce, and convey the cut lettuce to the leaf-removing device 4 for leaf-removing operation; further, the cut lettuce is conveyed in a lifting manner under the cooperation of the lifting conveyor belt 6 and the leaf-removing conveyor belt 5, and during the lifting process of the lettuce, upward extrusion is achieved under the guiding conveyance of the leaf-removing conveyor belt 5. The old leaves on the side wall of the lettuce fall off under the action of the corresponding blocking members, so as to remove the old leaves of the lettuce. The operation of the whole device on the lettuce has the functions of integration and automation, greatly improving the convenience of harvesting lettuce.

[0051] As a preferred mode of this embodiment, the harvester is composed of four parts, namely the frame 1, the harvesting conveyor device 3, the leaf-removing device 4 and the collection basket. A high-strength bottom plate and the frame 1 are used to carry the harvesting part and resist the destructive factors brought by various terrains. The whole body adopts a frame structure, which not only realizes the light weight of the product but also ensures the mechanical performance requirements during work. In terms of lettuce harvesting, the disc blade and the conveyor belt 13 are combined to realize the harvesting and transmission of lettuce.

[0052] In lettuce leaf-removing, the two pairs of leaf-removing conveyor belts 5 and leaf-removing plates 7 of the leaf-removing device 4 are used to remove the leaves of the lettuce and convey them to the rear collection box, thus completing the harvesting of the lettuce. In order to ensure the reliability of the transmission and be able to normally harvest lettuce in a harsh environment, four-wheel drive is used to ensure sufficient driving force. To ensure the stability of the vehicle body during operation, tires with a large diameter and a rough surface are adopted.

[0053] Preferably, the walking wheel assembly 2 includes 4 independently driven walking wheels 8 arranged at the bottom of the frame 1, forming a differential drive for the walking and steering of the frame 1.

[0054] By setting 4 independently driven walking wheels in the walking wheel assembly, differential drive between the wheels can be realized, and a steering effect can be achieved by using sliding friction. Moreover, it is suitable for field mountain terrains, making up for the shortcoming that lettuce harvesting is restricted by terrain, eliminating the physical structure of the mechanical differential, and only needing to design an electronic differential controller based on Ackermann steering for the front-wheel steering. By coordinately controlling the rotational speeds of the four hub motors respectively, the rotational speeds of each wheel can meet the requirements during turning, so as to achieve a steering purpose, greatly improving the efficiency of harvesting lettuce.

[0055] Analysis of the longitudinal component speed of the left wheels:

[0056] As Figure 5 shown, the speeds of the contact points of the two left wheels with the ground can be expressed as

[0057]

[0058] Among them, v1 and v2 respectively represent the linear velocities of points A and B, and r1 and r2 respectively correspond to their turning radii.

[0059] In right triangles A-Q-ICR and B-Q-ICR, formula (1) is transformed using trigonometric transformation and expressed as

[0060]

[0061] In the formula, α1 and α2 respectively represent the angles between A-ICR, B-ICR and Q-ICR.

[0062] When further simplifying formula (2), it is expressed as

[0063]

[0064] In the formula, and respectively represent the component velocities of v1 and v2.

[0065] Based on the above analysis, it can be known that the longitudinal component velocities of points A and B are the same. Similarly, it can be analyzed that the longitudinal component velocities of points C and D are the same, but the longitudinal component velocities of the left and right wheels are different.

[0066] Analysis of the lateral component velocity of the front wheels: Using the same idea as the analysis method of the longitudinal component velocities of the two side wheels, as Figure 5 shown, the velocities of the contact points of the two front wheels with the ground can be expressed as

[0067]

[0068] Among them, v4 represents the linear velocity of point D, and r4 corresponds to its turning radius.

[0069] In right triangles A-Q-ICR and D-P-ICR, formula (4) is transformed using trigonometric transformation and expressed as

[0070]

[0071] In the formula, α1 and α4 respectively represent the angles between A-ICR, D-ICR and P-ICR.

[0072] Because the lengths of AQ and DP are the same, when further simplifying formula (5), it is expressed as

[0073]

[0074] In the formula, and respectively represent the component velocities of v1 and v4.

[0075] Based on the above analysis, it can be known that the lateral component velocities of points A and D are the same. Similarly, it can be analyzed that the lateral component velocities of points B and C are the same, but the lateral component velocities of the front and rear wheels are different.

[0076] Advantages of the differential drive device: The reasons for using four-wheel differential to drive the combine harvester are as follows: (1) This technology involves the four front and rear wheels of the combine harvester in the steering process, thus improving the handling stability during high-speed steering and the maneuverability during low-speed turning of the combine harvester. (2) Compared with the traditional steering system, the mechanical structure of differential steering is relatively simple. Since components such as steering gears, steering rods, and steering gearboxes are not required, the overall weight and complexity of the vehicle can be reduced, and the manufacturing cost and maintenance cost are lowered. (3) Differential steering can achieve precise steering control by fine-tuning the rotational speed difference between the left and right wheels, making the vehicle more flexible, stable, and easy to control during operation. This is particularly important for vehicles that require precise operation, such as construction machinery and agricultural tractors. (4) Differential steering can enable the vehicle to more easily pass obstacles in complex terrains because it can fine-tune the vehicle's trajectory by controlling the rotational speed difference between the left and right wheels, thereby improving the vehicle's passability and off-road ability. (5) Compared with the traditional steering system, differential steering can reduce the damage to the ground when the vehicle is turning because it can achieve steering by controlling the rotational speed difference between the left and right wheels without generating a large lateral frictional force on the ground, thus reducing the wear of the ground. (6) Differential steering is applicable to various types of vehicles, including tracked vehicles, wheeled vehicles, agricultural tractors, construction machinery, etc., so it has strong versatility and adaptability.

[0077] Related calculations of the forces on the differential drive: During the driving process of the combine harvester chassis on the road surface, various resistances need to be overcome, so it is necessary to determine the power performance of the chassis. According to the fact that the motor output power is equal to the sum of the resistances acting on the moving chassis, the motion relationship is listed, and the vehicle driving equation is established:

[0078]

[0079] In the formula: ∑F is the sum of the driving resistances, including the rolling resistance ∑F, the air resistance ∑F, the gradient resistance F i and the acceleration resistance F i .

[0080] 1. Rolling resistance

[0081] When the moving chassis is driving on the ground, the tire and the ground contact will generate normal and tangential interaction forces, as well as the deformation of the tire when it rolls on the road surface. The rolling resistance formula is simplified to:

[0082] Ff = Wf#(8)

[0083] Where: W is the wheel load; f is the rolling resistance coefficient

[0084] 2. Air resistance

[0085] When the vehicle is moving in a straight line, the component of the air force acting on the vehicle in the direction of travel is called air resistance. Air resistance mainly consists of two parts: pressure resistance and frictional resistance. The air resistance formula is:

[0086]

[0087] Where: C D is the air resistance coefficient; A is the frontal area ( ); u is the vehicle speed (m / s)

[0088] 3. Grade resistance

[0089] When the mobile chassis climbs a slope, the component of the gravity of the chassis along the slope direction is the grade resistance. Its formula is:

[0090]

[0091] Where: G is the gravity acting on the mobile chassis (N); a is the slope angle.

[0092] 4. Acceleration resistance

[0093] When the mobile chassis is moving, there is an inertial force to maintain a constant speed. When accelerating, this inertial force must be overcome, which is the acceleration resistance. The formula for acceleration resistance is:

[0094]

[0095] Where: δ is the vehicle rotating mass conversion coefficient; m is the vehicle mass (kg); Traveling acceleration.

[0096] Since the working speed of the harvester is relatively low, it is approximately considered that the air resistance it receives is zero, that is. Then the energy consumption of the chassis is related to the rolling resistance, maximum slope and acceleration during driving. Secondly, the weight of the harvester chassis is designed to be 35 kg, and the rolling resistance coefficient is taken according to the data

[0097] First, calculate the traction force required by the motor according to the maximum vehicle speed. When the chassis is traveling on a horizontal road surface at the maximum designed vehicle speed, the grade resistance and the acceleration resistance are both 0, so

[0098] Fc = F f = fxG#(12)

[0099] Substitute each parameter into the formula to get F c = 87.5 N

[0100] Preferably, the harvesting and conveying device 3 includes a cutting tool 9 fixedly arranged at the bottom of the vehicle frame 1 and a clamping conveyor belt 10 arranged above the cutting tool 9. The clamping conveyor belt 10 is arranged obliquely upward or horizontally along the conveying direction; the cutting tool 9 includes two disc blade groups 11, and the disc-shaped blades 12 in the two disc blade groups 11 are horizontally adjacent and cooperatively arranged; the front end of the clamping conveyor belt 10 is placed above and in front of the two disc blade groups 11.

[0101] As a preferred embodiment of this example, disc-shaped blades 12 are added to the bottom end of the front part of the machine and directly driven by a motor to rotate. Such a cutting device is symmetrical left and right and is used to better cut the root parts of lettuce close to the ground. The cutting blades need to meet basic characteristics such as hardness, elasticity, wear resistance, and corrosion resistance, and also need to meet the requirements of mechanical structure parameters to achieve cutting effects such as small cutting resistance, neat cutting stubble, and smooth cross-section. When the lettuce is placed into the machine, the disc blades will cut it off. During this process, the lettuce moves forward, and at the same time, the disc blades cut behind the lettuce. In the actual lettuce harvesting process, the disc cutting blades should cut the lettuce at an angle perpendicular or nearly perpendicular to the lettuce itself. This cutting method can ensure that the lettuce is evenly cut into the required flat cut surface.

[0102] The finite element stress analysis of the cutting tool is as Figure 6 shown. Under the action of a 30 N force on the cutting edge and the upper surface of the tool, the tool made of tool steel will not produce stress deformation. This proves the rationality of the design of the cutting disc blades. When performing stress analysis on it, the yield force is 26 Mp, and the maximum stress concentration point is 22 Mp, which is less than the maximum yield force. The tool structure design is very reasonable. It can easily cut the lettuce without causing the transverse cutting tool to break.

[0103] Before the front harvesting knife harvests, the lettuce will first enter the sandwich of a pair of inclined clamping conveyor belts 10 through the forward movement of the trolley. A pair of clamping conveyor belts 10 are driven by a motor to drive the conveyor belt 13 to move. The left conveyor belt 13 rotates counterclockwise, and the right conveyor belt 13 rotates clockwise, so as to ensure that the lettuce can be smoothly moved to the rear-end leaf-removing mechanism after being clamped by the conveyor belt 13.

[0104] Since the motor drives the bearing and then a conveyor belt is sleeved for conveying work. The motor specification used here is the JGB37-520 coded motor with 12V / 110 revolutions per minute. At the same time, because the motor directly drives the bearing to drive the conveyor belt, the transmission ratio is 1:1 and the transmission efficiency η is also 1.

[0105] V = wrη #(13)

[0106] V: Linear velocity of the conveyor belt (unit: m / s)

[0107] w: Angular velocity of the motor (unit: rad / s)

[0108] r: Radius of the conveyor belt (unit: m)

[0109] η: Transmission efficiency (usually a decimal between 0 and 1 considering energy loss in transmission)

[0110] The diameter D of the conveyor belt = 35mm = 0.035m, so the radius

[0111] The rotational speed w of the motor = 1∶0rpm, since So

[0112] The transmission efficiency is n = 1.

[0113] From the above formula, the maximum linear velocity V of the conveyor belt can be obtained as V = 0.20m / s. At this speed, not only can an effective conveying rate be ensured, but also secondary damage to the lettuce during harvesting can be avoided, thus avoiding the impact on its freshness and taste caused by the harvesting loss of lettuce.

[0114] Preferably, the clamping conveyor belt 10 includes two conveyor belt units 26 arranged in parallel. The conveyor belt unit 26 includes a vertically arranged conveyor belt 13 and a power source for driving the conveyor belt 13. A plurality of flexible clamping strips 15 are arranged on the outer surface of the conveyor belt 13 in the width direction, and the plurality of flexible clamping strips 15 are evenly distributed in the length direction of the conveyor belt 13; the two power sources rotate in reverse synchronously for clamping the conveyor belt 10 to convey it into the frame 1.

[0115] As a preferred mode of this embodiment, the two clamping conveyor belts 10 rotate in reverse synchronously, which can effectively convey the lettuce to a high place. The design of the conveyor belt 13 can better wrap and hold the lettuce, avoiding the situation of unstable clamping and tipping due to the problem of the vertical center of gravity height of the lettuce.

[0116] According to the design requirements, at most six mature lettuce plants can be clamped on the conveyor belt at one time, further ensuring that the lettuce will not fall during the upward inclined conveyor process. The angle of the conveyor belt for clamping should also be considered as appropriate. The lettuce is affected by the conveying force and gravity as Figure 7 shown. G is the gravity of the lettuce, P is the conveying force of the conveyor belt on the lettuce, and F is the supporting force of the conveying mechanism on the lettuce obliquely upward. The force analysis is shown in the figure as the inclination angle θ of the conveyor belt. According to the force analysis, P = Fcosθ. During the conveying process, the inclination angle θ of the conveyor belt affects both the conveying force P and the supporting force F, and has an impact on the conveying of the lettuce.

[0117] In the actual harvesting production process, we fully consider that in order to further enhance the frictional force of the lettuce on the conveyor belt, the conveyor belt material is PVC (polyvinyl chloride) and is not easy to fall off. And multiple flexible clamping strips are manufactured using 3D printing technology. The lettuce will be stably moved upward by the conveyor belt.

[0118] Preferably, the deleafing conveyor belt 5 includes two stripping conveyor track units 16 arranged in parallel along the conveying direction and the deleafing plate 7. The stripping conveyor track unit 16 includes a track motor 20 vertically fixed on the vehicle frame 1 and a stripping conveyor track 18 rotatably connected to the track motor 20. A plurality of clamping heads 19 are arranged on the outer surface of the stripping conveyor track 18, and the plurality of clamping heads 19 are evenly distributed in the length direction of the stripping conveyor track 18; the two track motors 1 rotate in reverse synchronously for the deleafing conveyor belt 5 to convey to the outside of the vehicle frame 1.

[0119] By setting the cooperation between the two stripping conveyor track units 16 and the two deleafing plates 7, and making the distance between the two deleafing plates 7 less than the distance between the two stripping conveyor track units 16, the two deleafing plates 7 remove the old leaves of the clamped and guided and rising lettuce below the two stripping conveyor track units 16. The plurality of clamping heads 19 arranged on the outer surface of the stripping conveyor track 18 enhance the clamping stability effect on the lettuce. The setting of the two stripping conveyor track units 16 can hold the lettuce to prevent it from falling, and at the same time can also clamp the top of the lettuce to make it move upward stably.

[0120] During the lettuce harvesting process, in order to retain the stem of the main edible part and remove the old leaves, the processing mechanism of the harvester is designed as specifically Figure 1。The processing mechanism adopts a left-right symmetrical structure, including a leaf-removing plate at the top that can be used to remove leaves. The leaf-removing plate is made of acrylic. The lettuce is guided by the front conveyor belt to the leaf-removing processing device. On the outer surface of the support conveyor belt 21 in the lifting conveyor belt 6 below the leaf-removing processing device, there are a plurality of transverse rods 24, which can hold the lettuce to prevent it from tipping over. At the same time, the clamping conveyor belt 10 can also clamp the top of the lettuce to make it move up steadily. Then, through the obstruction of the acrylic plate, its old leaves are removed, thus realizing the overall process of removing the old leaves of the lettuce. After the processing is completed, the processed lettuce is directly conveyed to the next link to ensure an efficient and continuous operation process.

[0121] Preferably, the lifting conveyor belt 6 includes a support conveyor belt 21 and a driving roller shaft group 22. The driving roller shaft group 22 is inclinedly arranged on the vehicle frame 1, and the driving roller shaft group 22 is driven by a conveyor motor 23 fixedly arranged on the vehicle frame 1; on the outer surface of the support conveyor belt 21, there are a plurality of transverse rods 24. The transverse rods 24 are arranged in the width direction of the support conveyor belt 21, and the plurality of transverse rods 24 are evenly distributed in the length direction of the support conveyor belt 21.

[0122] As Figure 7 As shown in the force analysis diagram of the lettuce at the leaf-removing device, G is the gravity of the lettuce, FN is the support force of the support conveyor belt on it, and P is the conveying force of the conveyor belt: the transverse rods on the surface of the support conveyor belt are used to hold the lettuce to prevent it from falling down under the action of gravity; the acrylic plate is used to remove the old leaves of the lettuce. The lettuce moves slowly upward through the conveyance of the two upper and lower conveyor belts, namely the clamping conveyor belt 10 and the lifting conveyor belt 6. In this way, the acrylic plate can remove the old leaves of the lettuce through friction; the upper conveyor belt 13, that is, the clamping conveyor belt 10, is used to support the lettuce. Because the length of the lettuce is too long and the center of gravity is too high, a supporting force needs to be applied at its top to prevent it from falling down.

[0123] Preferably, a storage container 25 is arranged on the vehicle frame 1, and the storage container 25 is arranged directly below the output end of the lifting conveyor belt 6.

[0124] Preferably, the conveying speeds of the clamping conveyor belt 10, the leaf-removing conveyor belt 5, and the lifting conveyor belt 6 are the same. Keeping the conveying speeds of these three ends nearly similar can ensure that the lettuce moves stably on the conveyor belt.

[0125] The conveyor belts of the clamping conveyor belt 10 and the leaf-removing conveyor belt 5 are connected by a universal joint coupling 27. Through precise angle calculation and on-site physical debugging, one motor can drive two conveyor belts, so the transmission speeds at these two places are the same.

[0126] The linear speed of the lower conveyor belt is the same as the above calculation formula.

[0127]

[0128] V: Linear velocity of the conveyor belt (unit: m / s)

[0129] w: Angular velocity of the motor (unit: rad / s)

[0130] r: Radius of the conveyor belt (unit: m)

[0131] η: Transmission efficiency (usually a decimal between 0 and 1 considering energy loss during transmission)

[0132] The diameter D of the conveyor belt is 60 nm = 0.060 m, so the radius D is 60 nm = 0.060 m

[0133] The rotational speed w of the motor is 1:0 rpm. Since Therefore

[0134] The transmission efficiency is η = 1.

[0135] The calculated maximum linear velocity V of the conveyor belt is 0.35 m / s. Since the maximum velocity of the conveyor belt for cutting and conveying is only V = 0.2 m / s, and it is connected to the upper conveyor belt by a universal coupling, the velocities are the same. However, we need to keep the conveying velocities of these three ends nearly similar so that the lettuce can move stably on the conveyor belt.

[0136] Preferably, the clamping conveyor belt 10 is inclined, and its inclination angle is 20°.

[0137] If the inclination angle θ is too large, the lettuce is likely to fall and slide during transportation. If the inclination angle θ is too small, the conveying length will be extended, which is not convenient for the harvesting operation and cannot reserve a certain height for the subsequent processing device. According to the overall design requirements, the inclination angle θ of the conveyor belt under the rated state is determined to be 20°.

[0138] Preferably, the storage container 25 is detachably arranged on the vehicle frame 1, and a pressure sensor and a buzzer are electrically connected inside the storage container 25. When the weight of the lettuce contained in the storage container 25 reaches a predetermined amount, the buzzer gives an alarm by sounding.

[0139] The working principle and process of the present invention are as follows:

[0140] When the intelligent lettuce leaf-removing harvester provided by the present invention is working, the movement of the vehicle frame 1 is controlled by setting the traveling wheel assembly 2, so that the harvesting conveyor device 3 on the vehicle frame 1 can cut and convey the lettuce, and convey the cut lettuce to the leaf-removing processing device 4 for leaf-removing operation. Further, under the cooperation of the lifting conveyor belt 6 and the leaf-removing conveyor belt 5, the cut lettuce is conveyed in a lifting manner, and during the lifting process of the lettuce, upward extrusion is achieved under the guiding conveyance of the leaf-removing conveyor belt 5. The old leaves on the side wall of the lettuce fall off under the action of the corresponding blocking members, so as to remove the old leaves of the lettuce. The operation of the whole device on the lettuce has the functions of integration and automation, greatly improving the convenience of harvesting the lettuce.

[0141] Further, by setting the lifting conveyor belt 6, the cut lettuce conveyed by the clamping conveyor belt 10 is conveyed in a lifting manner, so that the lettuce can be vertically guided and clamped in the two upper rejection conveyor track units 16, and pass through between the two leaf-removing plates 7 for removing old leaves. Further, a plurality of cross bars 24 are arranged on the outer surface of the supporting conveyor belt 21, and a card slot is formed between the two cross bars 24, which is beneficial to clamping the lettuce and preventing it from falling down under the action of gravity. Because the length of the lettuce is too long and the center of gravity position is too high, the two rejection conveyor track units 16 guide and clamp the upper end of the lettuce, then a supporting force is applied at its top to prevent it from falling down, facilitating the stable removal of old leaves.

[0142] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered by the scope of the claims and the description of the present invention.

Claims

1. An intelligent lettuce leaf removing harvester, characterized in that: include: A frame, wherein a running wheel assembly is disposed at the bottom of the frame, and the running wheel assembly includes four independently driven running wheels disposed at the bottom of the frame, forming a differential drive for the running and steering of the frame; A harvesting and conveying device is arranged at the front end of the frame in the walking direction, and is used for cutting and conveying lettuce. The harvesting and conveying device includes a cutting tool fixedly arranged at the bottom of the frame and a clamping conveyor belt arranged above the cutting tool. The clamping conveyor belt is arranged upwardly inclined or horizontally along the conveying direction. The cutting tool includes two disc blade groups, and the disc-shaped blades in the two disc blade groups are arranged horizontally adjacent to each other; the front end of the clamping conveyor belt is placed in front of the two disc blade groups. When conveying lettuce, the lettuce is in a vertical state compared to the horizontal plane; A leaf removal device is arranged at the upper end of the frame and connected to the conveying end of the harvesting and conveying device, and is used for leaf removal of lettuce; and The defoliation processing device includes a defoliation conveyor belt arranged above the harvesting conveyor device and a lifting conveyor belt arranged below the defoliation conveyor belt, the defoliation conveyor belt cooperates with the defoliation plate in the lifting conveyor belt for lifting, squeezing and defoliating the lettuce, the defoliation conveyor belt includes two removal conveyor crawler units and the defoliation plate arranged in parallel along the conveying direction, the removal conveyor crawler unit includes a crawler motor vertically fixed on the frame and a removal conveyor crawler rotatably connected to the crawler motor, the outer surface of the removal conveyor crawler is provided with a plurality of clamping heads, and the plurality of clamping heads are evenly distributed in the length direction of the removal conveyor crawler; the two crawler motors rotate synchronously in opposite directions for conveying the defoliation conveyor belt to the outside of the frame, the lifting conveyor belt includes a supporting conveyor belt and a driving roller group, the driving roller group is tilted on the frame, and the driving roller group is driven by a conveying motor fixed on the frame; the outer surface of the supporting conveyor belt is provided with a plurality of transverse rods, the transverse rods are arranged in the width direction of the supporting conveyor belt, and the plurality of transverse rods are evenly distributed in the length direction of the supporting conveyor belt.

2. The intelligent lettuce leaf removing harvester according to claim 1, characterized in that: The clamping conveyor belt includes two parallel conveyor belt units, each of which includes a vertically arranged conveyor belt and a power source for driving the conveyor belt. A plurality of flexible clamping strips are arranged in the width direction of the outer surface of the conveyor belt, and the plurality of flexible clamping strips are evenly distributed in the length direction of the conveyor belt. The two power sources rotate synchronously in opposite directions to clamp the conveyor belt and transport it to the inside of the frame.

3. The intelligent lettuce leaf removing harvester according to claim 1, characterized in that: A storage container is arranged on the frame, and the storage container is arranged just below the output end of the lifting conveyor belt.

4. The intelligent lettuce leaf removing harvester according to claim 2, characterized in that: The end of the rejection conveyor belt is coaxially connected to the end adjacent to the driving conveyor belt, and the conveying speeds of the clamping conveyor belt, the leaf removal conveyor belt and the lifting conveyor belt are consistent.

5. The intelligent lettuce leaf removing harvester according to claim 1, characterized in that: The clamping conveyor belt is tilted, and its inclination angle is 20°.

6. The intelligent lettuce leaf removing harvester according to claim 3, characterized in that: The storage container is detachably arranged on the vehicle frame, and an electrically connected pressure sensor and a buzzer are arranged in the storage container.

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