A low-impact rice pot body blanket seedling precision transfer device and transfer method

Abstract

The application discloses a low-impact rice pot body blanket seedling precision transfer device and a transfer method. In the application, the box is driven to reciprocate by a transverse movement mechanism, so that each pot seedling in each row of the two pot body blanket seedlings placed on two belt conveying mechanisms is sequentially translated to a seedling taking position, transverse seedling conveying work of the pot body blanket seedlings is realized, and after the transverse seedling conveying work of each row of pot seedlings is completed, the two belt conveying mechanisms on the box are driven to work by a longitudinal movement mechanism, so that the two rows of pot body blanket seedlings are conveyed by a distance of one row of pot seedlings, longitudinal seedling conveying work of the pot body blanket seedlings is realized, and a curve groove wheel is adopted in the longitudinal movement mechanism. A plurality of trapezoidal outer teeth are uniformly distributed on the outer surface of the conveying belt of the belt conveying mechanism, and a plurality of circular platform protrusions are arranged equidistantly along the width direction of the conveying belt between every two adjacent trapezoidal outer teeth. The application can realize the precision transfer of the rice pot body blanket seedlings, and the longitudinal seedling conveying precision and stability are high.

Description

Technical Field

[0001] This invention belongs to the field of agricultural machinery technology, specifically relating to a low-impact rice seedling pot-shaped blanket-like precision transfer device and transfer method. Background Technology

[0002] The mechanized and simplified rice transplanting technology using rice seedlings in pots effectively reduces root damage during planting and offers advantages such as early rooting, early survival, and early tillering. It improves seedling survival rate and shortens the field growing period, which is beneficial for resolving crop rotation conflicts in double-cropping rice areas, increasing grain yield, and improving the level of mechanization in planting, thus meeting the requirements for increasing rice yield per unit area. The function of the rice seedling transfer device is to accurately supply seedlings to the transplanting mechanism. However, existing transfer devices experience significant impact during high-speed operation, leading to unstable longitudinal seedling delivery accuracy and hindering the high-speed development of rice transplanting. Furthermore, due to the structural characteristics of traditional seedling transfer devices, it is difficult to achieve precise positioning and effective constraint of the seedlings in the pots. This results in lateral movement and longitudinal slippage of the seedlings during transport, causing errors and problems such as "half-pot" seedlings and low whole-pot rates. It also exacerbates the compression and deformation of the seedlings during transport, severely damaging the root system. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and to propose a low-impact rice seedling pot-shaped blanket-like precision transfer device and transfer method.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] The present invention provides a low-impact rice seedling tray precision transfer device, comprising a longitudinal moving mechanism, a seedling box, a transverse moving mechanism, and a frame.

[0006] The seedling box includes a box body, a slide rail, and a belt conveyor mechanism; the box body is arranged at an inclination, and the lower end of the box body forms a sliding pair with the horizontally arranged slide rail, which is fixed to the frame; the box body has two rectangular openings arranged at intervals, and a belt conveyor mechanism is provided at each of the two rectangular openings, with the input end of the belt conveyor mechanism being higher than the output end, the conveying direction of the belt conveyor mechanism being perpendicular to the slide rail, and multiple trapezoidal external teeth that are integrally formed and evenly distributed along the circumference are fixed on the outer surface of the conveyor belt of the belt conveyor mechanism, and multiple frustum protrusions that are equidistantly arranged along the width direction of the conveyor belt are fixed between each two adjacent trapezoidal external teeth;

[0007] The lateral movement mechanism includes a drive shaft, a transmission shaft, striking rods, a double helical shaft, and a slider; the drive shaft, transmission shaft, and double helical shaft are all parallel to the slide rail and form a rotating pair with the mechanism; one end of the drive shaft is connected to the optical shaft section of one end of the double helical shaft through a gear pair, and the other end is connected to the transmission shaft through a chain drive mechanism; striking rods are fixed at both ends of the transmission shaft; the slider and the threaded section in the middle of the double helical shaft form a threaded pair and are fixed to the housing;

[0008] The longitudinal moving mechanism includes a curved grooved wheel, a dial, a rocker arm, a planetary carrier, a first cylindrical gear, a ring gear carrier, a second cylindrical gear, a rotating shaft, and a return torsion spring. The rocker arm, planetary carrier, and ring gear carrier are arranged sequentially along the axial direction of the rotating shaft, which is located between two conveyor mechanisms and is coaxially fixed to the drive shafts of the two conveyor mechanisms. An integrally formed cylindrical column and a return torsion spring on the rocker arm are both fitted onto the rotating shaft, forming a rotating pair with the rotating shaft. The two ends of the return torsion spring are fixed to the cylindrical column and the rotating shaft, respectively. The planetary carrier is supported on the cylindrical column by a one-way bearing. The ring gear carrier is fitted onto the rotating shaft and fixed to the housing. The two coaxially fixed... Cylindrical gear two is placed inside the ring gear carrier and forms a revolute pair with the rotating shaft; cylindrical gear one and drive pin gear are both placed between cylindrical gear two and the ring gear carrier, and cylindrical gear one meshes with the internal teeth of cylindrical gear two near the planet carrier and the ring gear carrier, forming a revolute pair with the planet carrier; drive pin gear meshes with the internal teeth of another cylindrical gear two away from the planet carrier and the ring gear carrier, forming a revolute pair with the integrally formed connecting plate on the ring gear carrier; a dial is fixed on the drive pin gear, and two drive pins are fixed on the dial symmetrically arranged about the center of the dial; the curved grooved wheel is fixed to the rotating shaft.

[0009] Preferably, the slide rail is fixed to the frame by a plurality of support frames arranged at intervals.

[0010] Preferably, the conveyor mechanism includes a drive shaft, a driven shaft, a conveyor roller, and a conveyor belt. Both the drive shaft and the driven shaft form a rotating pair with the housing. A conveyor roller is fixed on both the drive shaft and the driven shaft, and the two conveyor rollers are connected by the conveyor belt.

[0011] More preferably, the inner surface of the conveyor belt is provided with a plurality of integrally formed and circumferentially distributed internal teeth, and a plurality of integrally formed and circumferentially distributed trapezoidal external teeth on the conveyor roller mesh with a plurality of internal teeth on the inner side of the conveyor belt.

[0012] Preferably, the chain drive mechanism includes a driving sprocket, a chain, and a driven sprocket, with the driving sprocket and the driven sprocket fixed to the drive shaft and the transmission shaft, respectively, and connected by the chain.

[0013] Preferably, a sleeve is fixedly fitted on the rotating shaft; the cylindrical tube and the reset torsion spring are both fitted on the sleeve, the cylindrical tube and the sleeve form a rotating pair, and the two ends of the reset torsion spring are fixed to the cylindrical tube and the sleeve; the cylindrical gear II forms a rotating pair with the sleeve; and the curved grooved wheel is fixed to the sleeve.

[0014] The present invention discloses a low-impact rice pot-shaped blanket seedling precision transfer device and a rice pot-shaped blanket seedling transfer method, the details of which are as follows:

[0015] Two potted blanket-shaped seedlings are placed on two conveyor belts with conveyor mechanisms. Each trapezoidal external tooth on each conveyor belt is engaged between two adjacent rows of seedlings at the bottom of the corresponding potted blanket-shaped seedling, and each frustum-shaped protrusion is engaged between two adjacent columns of seedlings. An external power source drives the shaft to rotate, which in turn drives the double helix shaft to rotate via a gear pair. This, in turn, drives the transmission shaft and each striking rod to rotate via a chain drive mechanism. As the double helix shaft rotates, the slider moves the box back and forth along the slide rail, causing each row of the two potted blanket-shaped seedlings placed on the box to be moved sequentially to the seedling picking position, thus performing the lateral feeding of the potted blanket-shaped seedlings. Whenever the slider moves to the end of the threaded section of the double helix shaft, one of the striking rods at the same end contacts the swing rod, pushing the swing rod to drive the cylinder to rotate clockwise. The cylinder drives the planetary carrier to rotate via a one-way bearing, and the planetary carrier drives the cylindrical gear one to rotate around the axis. Because the cylindrical gear one is close to the row The internal teeth of one cylindrical gear 2 on the planetary frame and the ring gear frame are meshed, causing the cylindrical gear 1 to rotate around its own central axis while rotating around the rotating shaft. This, in turn, drives the two cylindrical gear 2 to rotate. The cylindrical gear 2 away from the planetary frame meshes with the drive pin gear, thereby driving the drive pin gear and the dial to rotate. This causes a drive pin on the dial to enter a radial groove in the curved groove wheel, driving the curved groove wheel to rotate. The curved groove wheel drives the two drive shafts with conveyor mechanisms to rotate through the rotating shaft, causing the two conveyor mechanisms to work and convey the two potted blanket-shaped seedlings downward. When the striking rod disengages from the swing rod, the column cylinder reverses to its original position under the restoring force of the return torsion spring. At this time, the one-way bearing unlocks, the column cylinder no longer drives the planetary frame to rotate, and the two conveyor mechanisms stop working. At this time, the two potted blanket-shaped seedlings have been conveyed downward by one row of seedlings, performing the longitudinal seedling delivery work.

[0016] Preferably, the design process of the curved Geneva mechanism, consisting of a curved Geneva wheel, a dial, and two drive pins, is as follows:

[0017] Let the rotation center of the dial be point O, the radius of the drive pin be r, the installation radius of the drive pin be r0, the rotation center of the curved grooved wheel be point O1, the center distance between the dial and the curved grooved wheel be R, and when the center of one tooth of the curved grooved wheel coincides with point O, the midpoint of the adjacent tooth behind it is point O2. Let the number of grooves on the curved grooved wheel be Z. Then the pitch angle of the curved grooved wheel is... The length of line segment OO2 is The initial and final positions of the driving pin are points A0 and B0, respectively, and point B0 is the midpoint of line segment OO2. Line segment O1B0 perpendicularly bisects line segment OO2. The radial groove profile of the curved Geneva wheel consists of an arc segment A0A1 and a curved segment A1G, with the curved segment A1G and the arc segment A0A1 being tangent at point A1. The theoretical center circle of the driving pin intersects the line segment OO1 at point E. Let the deepest point of the radial groove of the curved Geneva wheel be point G, which lies on a circle centered at point O1 and passing through point E. This is further defined by setting... The angle is determined, and the radius of the circle centered at point O1 and passing through point E is... The radial groove major diameter of the curved groove wheel is The radial groove minor diameter is ;

[0018] Set dial to When the dial rotates at a constant speed and the center point of the driving pin moves along the arc segment A0A1, the angle of rotation of the dial is... With the curved pulley stationary, as the center point of the drive pin moves along the curved segment A1G, the angle of rotation of the dial relative to the line segment OA1 is... And drive the center point to reach At point 1, the curved groove wheel rotates. Then the center point of the drive pin moves in the opposite direction along the radial groove until the dial rotates 180° relative to its initial position, and the swivel wheel rotates to the indexing angle. Complete one vertical seedling delivery operation;

[0019] The arc segment A0A1 is part of the theoretical center circle of the drive pin, while the curve segment A1G is solved in reverse according to the preset motion law, using the relative motion relationship between the dial angle and the curve groove wheel angle.

[0020] More preferably, the design process for curve segment A1G is as follows:

[0021] Establish a Cartesian coordinate system for the dial with point O as the origin, the axis containing line segment OO1 as the x-axis, and the axis perpendicular to the x-axis as the y-axis. Establish a Cartesian coordinate system for the curved grooved wheel with point O1 as the origin, the axis containing line segment OO1 as the x-axis, and the axis perpendicular to the x-axis as the y-axis. The coordinates of point O in the Cartesian coordinate system of the curved grooved wheel are: Let the angle between line segment OA1 and the x-axis be such that the center point of the drive pin is at point A1. The local coordinates of the drive pin center point in the dial plane rectangular coordinate system are:

[0022] (1)

[0023] The absolute position vector of the drive pin center point in the Cartesian coordinate system of the curved grooved wheel plane is:

[0024] (2)

[0025] Let the rotation angle of the curved groove wheel be... Establish the coordinate transformation matrix:

[0026] (3)

[0027] The coordinate matrix of the center point of the drive pin relative to the curved grooved wheel is:

[0028] (4)

[0029] Substituting equation (2) into equation (4), we get:

[0030] (5)

[0031] Converting equation (5) to polar coordinates, the polar radius of the drive pin center point relative to the center of rotation of the curved groove wheel is... and polar angle They are respectively:

[0032] (6)

[0033] Construct a motion law model for a curved grooved wheel based on a fifth-order polynomial:

[0034] (7)

[0035]

[0036] In the formula, The angle that the drive pin center point needs to rotate relative to the curved pulley from point A1 to point G;

[0037] The time corresponding to the starting point of the curve segment. The function is the time corresponding to the termination point of the curve segment. Satisfying the boundary constraint set :

[0038] (8)

[0039] and

[0040] (9)

[0041] In the formula, , and These are the rotation of the center point of the drive pin. Then, the angular displacement, angular velocity, and angular acceleration of the curved grooved wheel;

[0042] Boundary constraint set Substituting into equation (9), we get:

[0043] (10)

[0044] The motion law model expression for the curved Geneva wheel is:

[0045] (11)

[0046] in:

[0047]

[0048] Adjusted using a genetic algorithm , , and The motion law model of the curved groove wheel is optimized, and the optimized motion law model of the curved groove wheel is substituted into equation (5) to obtain the optimized A1G parameter equation of the curved segment.

[0049] More preferably, adjusting through a genetic algorithm , , and The process of optimizing the motion law model of the curved Geneva wheel is as follows:

[0050] Define design variables and determine the design variables. The range of values ​​for each parameter, and the design variables. for:

[0051] (12)

[0052] Define the objective function for:

[0053] (13)

[0054]

[0055] In the formula: , , and All are weighting coefficients; As an indicator of global smoothness and flexibility; For key position speed control indicators, Let be the angular velocity of the curved grooved wheel at the critical position j. Let M be the set of key locations, and M be the number of key locations. It serves as a peak suppression and oscillation control indicator. Let be the angular acceleration of the curved grooved wheel. This represents the number of peak values ​​in the angular velocity curve of the curved groove wheel. This represents the number of peak values ​​in the angular acceleration curve of the curved groove wheel. As a penalty factor; As a boundary stationarity index, and Let A1G be the angular velocity at the start and end points of the curve segment. and Let A1G be the angular acceleration at the starting and ending points of the curve segment. This is the weighting coefficient between angular velocity and angular acceleration;

[0056] Set the population size, number of iterations, crossover probability, and mutation probability, and derive the results using a genetic algorithm. , , and The optimal value is obtained and substituted into equation (11) to obtain the optimized motion law model of the curved groove wheel.

[0057] The present invention has the following beneficial effects:

[0058] This invention enables precise transfer of rice seedlings in pots, exhibiting high accuracy and stability in longitudinal seedling delivery. Specifically, the invention uses a lateral movement mechanism to drive the box to reciprocate, causing each row of seedlings in two pots placed on two conveyor belts to be sequentially moved to the seedling collection position, thus achieving lateral seedling delivery. After each row of seedlings is delivered laterally, the longitudinal movement mechanism drives the two conveyor belts on the box to deliver the two rows of seedlings downwards by the distance of one row, thus achieving longitudinal seedling delivery. The outer surface of the conveyor belts of the conveyor belts is fixed with multiple trapezoidal teeth evenly distributed circumferentially, and multiple frustum-shaped protrusions are fixed between each pair of adjacent trapezoidal teeth, equidistantly arranged along the width of the conveyor belt. The trapezoidal teeth are used to engage between adjacent rows of seedlings at the bottom of the pot, and the frustum-shaped protrusions are used to engage between adjacent rows. This design achieves precise lateral and longitudinal positioning of the seedlings in the pots, preventing root deformation caused by poor positioning during transport when using belt friction drives. Furthermore, addressing the issue of flexible impact during the start-up of traditional linear grooved wheel longitudinal seedling delivery mechanisms, this invention employs curved grooved wheels. The radial groove contour of the curved grooved wheel consists of circular arc segments and curved segments. By constructing a motion law model of the curved grooved wheel based on a high-order polynomial and establishing an objective function with multi-objective optimization evaluation indicators, a genetic algorithm is used to globally optimize key design parameters, resulting in the optimal motion law model of the curved grooved wheel and the optimal parametric equations for the curved segments. This eliminates the flexible impact at the start-up of the grooved wheel mechanism, improving the accuracy and stability of seedling delivery. Attached Figure Description

[0059] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0060] Figure 2 This is a schematic diagram of the seedling box in this invention;

[0061] Figure 3 This is a schematic diagram of the structure with a conveying mechanism in this invention;

[0062] Figure 4 This is a schematic diagram of the lateral movement mechanism in this invention;

[0063] Figure 5 This is a schematic diagram of the longitudinal moving mechanism in this invention;

[0064] Figure 6 This is an exploded view of the longitudinal moving mechanism in this invention;

[0065] Figure 7 This is a simplified structural diagram of the curved Geneva mechanism in this invention;

[0066] Figure 8 This is a comparison diagram of the radial groove profile, angular displacement, angular velocity, and angular acceleration curves of the curved groove wheel before and after optimization in this invention.

[0067] Figure 9 This is a motion curve diagram of the optimized curved Geneva mechanism in this invention;

[0068] Figure 10 This is a motion curve diagram of a traditional linear Geneva mechanism. Detailed Implementation

[0069] The present invention will now be further described with reference to the accompanying drawings.

[0070] like Figure 1 As shown, the present invention provides a low-impact rice seedling tray precision transfer device, which includes a longitudinal moving mechanism 1, a seedling box 2, a transverse moving mechanism 3, and a frame (not shown in the figure).

[0071] like Figure 2 and Figure 3As shown, the seedling box 2 includes a box body 21, a slide rail 22, a support frame 23, and a belt conveyor mechanism. The box body 21 is arranged at an angle, and the lower end of the box body 21 forms a sliding pair with the horizontally arranged slide rail 22. The slide rail 22 is fixed to the frame through several support frames 23 arranged at intervals. The box body 21 has two rectangular openings arranged at intervals, and a belt conveyor mechanism is provided at each of the two rectangular openings. The input end of the belt conveyor mechanism is higher than the output end, and the conveying direction of the belt conveyor mechanism is perpendicular to the slide rail 22. The outer surface of the conveyor belt of the belt conveyor mechanism has multiple trapezoidal external teeth 24 integrally formed and evenly distributed along the circumference. Between each pair of adjacent trapezoidal outer teeth 24, there are multiple frustum protrusions 26 arranged at equal intervals along the width of the conveyor belt; wherein, the distance between each pair of adjacent trapezoidal outer teeth 24 is equal to the distance between four rows of seedlings in the pot, and the distance between each pair of adjacent frustum protrusions 26 is equal to the distance between four rows of seedlings. The trapezoidal outer teeth 24 are used to lock between two adjacent rows of seedlings at the bottom of the pot, and the frustum protrusions 26 are used to lock between two adjacent rows of seedlings, so as to achieve precise horizontal and vertical positioning of the potted blanket seedlings. This can prevent the seedlings from sliding and causing root deformation due to poor positioning effect during the conveying process when using belt friction transmission.

[0072] like Figure 4 As shown, the lateral movement mechanism 3 includes a drive shaft 301, a transmission shaft 307, a striking rod 310, a double helix shaft 311, and a slider 313. The drive shaft 301, transmission shaft 307, and double helix shaft 311 are all parallel to the slide rail 22 and form a rotating pair with the machine frame. One end of the drive shaft 301 is connected to the optical shaft section of one end of the double helix shaft 311 through a gear pair, and the other end is connected to the transmission shaft 307 through a chain drive mechanism. The striking rods 310 are fixed at both ends of the transmission shaft 307. The slider 313 and the threaded section in the middle of the double helix shaft 311 form a threaded pair and are fixed to the housing 21 of the seedling box 2.

[0073] like Figure 5 and Figure 6As shown, the longitudinal moving mechanism 1 includes a curved grooved wheel 101, a dial 102, a rocker arm 103, a planetary carrier 105, a first cylindrical gear 106, a ring gear carrier 107, a second cylindrical gear 108, a rotating shaft 109, and a return torsion spring 113. The rocker arm 103, planetary carrier 105, and ring gear carrier 107 are arranged sequentially along the axial direction of the rotating shaft 109. The rotating shaft 109 is located between two conveyor mechanisms and is coaxially fixed with the drive shafts of the two conveyor mechanisms. The integrally formed cylindrical column and the return torsion spring 113 on the rocker arm 103 are both sleeved on the rotating shaft 109. The cylindrical column and the rotating shaft 109 form a revolute pair. The two ends of the return torsion spring 113 are fixed to the cylindrical column and the rotating shaft 109, respectively. The planetary carrier 105 is supported on the cylindrical column by a one-way bearing 104. The ring gear carrier 107 is sleeved on the rotating shaft 109 and fixed to the housing 21. Two coaxially fixed cylindrical gears 108 are placed inside the ring gear carrier 107 and both form a revolute pair with the rotating shaft 109. Cylindrical gear 106 and drive pin gear 112 is positioned between cylindrical gear 108 and ring gear carrier 107. Cylindrical gear 106 meshes with the internal teeth of cylindrical gear 108 and ring gear carrier 107 near planet carrier 105, forming a revolute pair with planet carrier 105. Drive pin gear 112 meshes with the internal teeth of cylindrical gear 108 and ring gear carrier 107 away from planet carrier 105, forming a revolute pair with the integrally formed connecting plate on ring gear carrier 107. A dial 102 is fixed on drive pin gear 112, and two drive pins are fixed on dial 102 symmetrically arranged about the center of dial. Curved grooved wheel 101 is fixed to rotating shaft 109. Curved grooved wheel 101, dial 102 and two drive pins constitute curved grooved wheel mechanism.

[0074] In a preferred embodiment, the two ends of the drive shaft 301 are supported on the frame by bearing housing 1 302 and bearing housing 2 304.

[0075] In a preferred embodiment, the gear pair includes a meshing first gear 303 and a second gear 312, with the second gear 312 and the first gear 303 respectively fixed to the optical axis section of the double helical shaft 311 and the drive shaft 301.

[0076] In a preferred embodiment, the chain drive mechanism includes a drive sprocket 305, a chain 306, and a driven sprocket 309. The drive sprocket 305 and the driven sprocket 309 are respectively fixed on the drive shaft 301 and the transmission shaft 307, and are connected by the chain 306.

[0077] In a preferred embodiment, the drive shaft 307 is supported on the frame at both ends by two bearing seats 308.

[0078] In a preferred embodiment, the striking rod 310 is fixed to the drive shaft 307 by a set screw 314.

[0079] In a preferred embodiment, the conveyor mechanism includes a drive shaft, a driven shaft, a conveyor roller 25, and a conveyor belt. Both the drive shaft and the driven shaft form a rotating pair with the housing 21. A conveyor roller 25 is fixed on both the drive shaft and the driven shaft, and the two conveyor rollers 25 are connected by the conveyor belt.

[0080] More preferably, the inner surface of the conveyor belt is provided with a plurality of integrally formed and circumferentially distributed internal teeth, and a plurality of integrally formed and circumferentially distributed trapezoidal external teeth on the conveyor roller 25 mesh with a plurality of internal teeth on the inner side of the conveyor belt.

[0081] In a preferred embodiment, a sleeve 110 is fixedly sleeved on the rotating shaft 109, and the cylindrical tube and the reset torsion spring 113 are both sleeved on the sleeve 110. The cylindrical tube and the sleeve 110 form a rotating pair, and the two ends of the reset torsion spring 113 are fixed to the cylindrical tube and the sleeve 110. The cylindrical gear 108 and the sleeve 110 form a rotating pair. The curved grooved wheel 101 is fixed to the sleeve 110.

[0082] More preferably, the cylinder is supported on the sleeve 110 by a deep groove ball bearing 111.

[0083] This invention discloses a method for precise transplanting of low-impact rice seedlings in pots, as detailed below:

[0084] Two potted blanket-shaped seedlings are placed on two conveyor belts with conveyor mechanisms. Each trapezoidal external tooth 24 on each conveyor belt engages between two adjacent rows of seedlings at the bottom of the corresponding potted blanket-shaped seedling, providing longitudinal positioning. Each frustum-shaped protrusion 26 engages between two adjacent rows of seedlings, providing lateral positioning. An external power source drives the shaft 301 to rotate (either directly driven by a motor or by the wheel axle on the mobile chassis driven by a chain drive mechanism). The drive shaft 301 drives the double helix shaft 311 to rotate via a gear pair, and drives the transmission shaft 307 and each striking rod 310 to rotate via the chain drive mechanism. As the double helix shaft 311 rotates, the slider 313 drives the box 21 to reciprocate along the slide rail 22, so that the seedlings in each row of the two potted blanket-shaped seedlings placed on the box 21 are aligned sequentially. Moved to the seedling picking position, the horizontal feeding of the blanket-shaped seedlings in the pot is achieved. Whenever the slider 313 moves to the end of the threaded section of the double helical shaft 311, a striking rod 310 located at the same end contacts the swing rod 103, pushing the swing rod 103 to rotate the cylinder clockwise. The cylinder drives the planetary carrier 105 to rotate via a one-way bearing. The planetary carrier 105 drives the first cylindrical gear 106 to rotate around the rotating shaft 109. Because the first cylindrical gear 106 interacts with a second cylindrical gear 108 and a ring gear near the planetary carrier 105... The internal teeth of the planetary carrier 107 are all meshed, causing the first cylindrical gear 106 to rotate around the rotating shaft 109 while also rotating around its own central axis. This, in turn, drives the two second cylindrical gears 108 to rotate. One of the second cylindrical gears 108, located away from the planetary carrier 105, meshes with the drive pin gear 112, thereby driving the drive pin gear 112 and the dial 102 to rotate. This causes a drive pin on the dial 102 to enter a radial groove in the cam groove wheel 101, driving the cam groove wheel 101 to rotate. The cam groove wheel 101 then... The rotating shaft 109 drives the two drive shafts with conveying mechanisms to rotate, causing the two conveying mechanisms to work and convey the two potted blanket seedlings downward. When the striking rod 310 disengages from the swing rod 103, the column is reversed to its original position under the restoring force of the return torsion spring 113. At this time, the one-way bearing 104 is unlocked, the column does not drive the planetary frame 105 to rotate, and the two conveying mechanisms stop working. At this time, the two potted blanket seedlings have been conveyed downward by one row of seedlings, thus realizing the longitudinal seedling delivery work of the potted blanket seedlings.

[0085] The design process of the curved Geneva mechanism, consisting of the curved Geneva 101, the dial 102, and two drive pins, is as follows:

[0086] like Figure 7As shown, let the rotation center of the dial 102 be point O, the radius of the drive pin be r, the installation radius of the drive pin (the distance from the center of the drive pin B1 to the center of the dial) be r0, the rotation center of the curved grooved wheel 101 be point O1, the center distance between the dial 102 and the curved grooved wheel 101 be R, when the center of one tooth of the curved grooved wheel 101 coincides with point O, the midpoint of the adjacent tooth behind it is point O2, and the number of grooves of the curved grooved wheel 101 is Z. Then the pitch angle of the curved grooved wheel 101 is... The length of line segment OO2 is The initial and final positions of the driving pin are points A0 and B0, respectively, and point B0 is the midpoint of line segment OO2. Line segment O1B0 perpendicularly bisects line segment OO2. The radial groove profile of the curved groove wheel 101 is composed of an arc segment A0A1 and a curved segment A1G. To ensure that the speed of the curved groove wheel 101 is continuous and smooth at the intersection of the arc segment and the curved segment during movement, the curved segment A1G and the arc segment A0A1 are tangent at point A1. The theoretical center circle of the driving pin (a circle with center O and radius r0) intersects the line segment OO1 at point E. Let the deepest point of the radial groove of the curved groove wheel 101 be point G. Point G is located on the circle with center O1 and passing through point E. This is further defined by setting... The angle is determined, and the radius of the circle centered at point O1 and passing through point E is... The radial groove major diameter of the curved groove wheel 101 is The radial groove minor diameter is .

[0087] When in operation, dial 102 is set to... When the drive pin center point moves along the arc segment A0A1 at a constant speed, the rotation angle of the dial 102 is: With the curved grooved wheel 101 stationary, as the center point of the drive pin moves along the curved segment A1G, the rotation angle of the dial 102 relative to the line segment OA1 is... And drive the center point to reach At point 101, the curved groove wheel 101 rotates. Then, the center point of the drive pin moves in the opposite direction along the radial groove (from point G to point A0) until the dial 102 rotates 180° relative to its initial position (including the angle). and angle ), Curved Grooved Wheel 101 Rotation Pitch Angle (Include This completes one vertical seedling delivery operation.

[0088] Based on the motion process of the curved grooved wheel 101, the arc segment A0A1 can be designed according to the geometric dimensions of the dial 102, and is part of the theoretical center circle of the drive pin. However, the curved segment A1G needs to be solved in reverse according to the preset motion law (a fifth-order polynomial), using the relative motion relationship between the dial angle and the curved grooved wheel angle. The design process of the curved segment A1G is as follows:

[0089] Establish a Cartesian coordinate system for the dial with point O as the origin, the axis containing line segment OO1 as the x-axis, and the axis perpendicular to the x-axis as the y-axis. Establish a Cartesian coordinate system for the curved grooved wheel with point O1 as the origin, the axis containing line segment OO1 as the x-axis, and the axis perpendicular to the x-axis as the y-axis. The coordinates of point O in the Cartesian coordinate system of the curved grooved wheel are: Let the angle between line segment OA1 and the x-axis be such that the center point of the drive pin is at point A1. The local coordinates of the drive pin center point in the dial plane rectangular coordinate system are:

[0090] (1)

[0091] The absolute position vector of the drive pin center point in the Cartesian coordinate system of the curved grooved wheel plane is:

[0092] (2)

[0093] Let the rotation angle of the curved groove wheel be... To convert the absolute motion of the drive pin center point into relative motion, the absolute position vector of the drive pin center point needs to be projected onto a moving coordinate system that rotates with the curved grooved wheel. The corresponding coordinate transformation matrix is:

[0094] (3)

[0095] The coordinate matrix of the center point of the drive pin relative to the curved grooved wheel is:

[0096] (4)

[0097] Substituting equation (2) into equation (4), and expanding the matrix multiplication, we can simplify using trigonometric identities to obtain:

[0098] (5)

[0099] Equation (5) is the parametric equation of the curve segment A1G of the radial groove profile of the curved groove wheel, which is the motion trajectory of the center point of the driving pin relative to the moving coordinate system. Further converting equation (5) into polar coordinate form, the polar radius of the center point of the driving pin relative to the rotation center of the curved groove wheel is... and polar angle They are respectively:

[0100] (6)

[0101] Furthermore, to address the issue of significant impact in existing high-speed rice transplanting operations leading to unstable longitudinal seedling delivery accuracy, the designed curve segment A1G must meet the requirement of no impact (no abrupt change in angular acceleration) at both the starting point (A1 point) and the ending point (G point). A motion law model of the curved wheel based on a fifth-order polynomial is constructed, abstracting the design of the trajectory of curve segment A1G into a mathematical optimization problem. The motion law model of the curved wheel is as follows:

[0102] (7)

[0103]

[0104] In the formula, The angle that the drive pin center point needs to rotate relative to the curved pulley from point A1 to point G;

[0105] This corresponds to the time when the starting point of the curve segment reaches point A1, i.e., the time when the center point of the drive pin reaches point A1. The coefficient vector represents the time corresponding to the end point of the curve segment, i.e., the time when the center point of the corresponding drive pin reaches point G. ,function Boundary constraint set must be satisfied :

[0106] (8)

[0107] and

[0108] (9)

[0109] In the formula, , and These are the rotation of the center point of the drive pin. Afterwards, the angular displacement of the curved grooved wheel (i.e. ), angular velocity and angular acceleration.

[0110] Boundary constraint set Substitute into equation (9) to solve for the coefficient vector We can obtain:

[0111] (10)

[0112] The motion law model expression for the curved Geneva wheel is:

[0113] (11)

[0114] in:

[0115]

[0116] The motion law model of the curved groove wheel is subject to , , and Four parameters influence the adjustment via a genetic algorithm. , , and To optimize the motion law of the curved grooved wheel, design variables are defined. for:

[0117] (12)

[0118] Through analysis , , and The influence of the value of on the motion of the curved groove wheel was initially selected in this embodiment. , , , And determine the value range of each parameter: The value range is 30°~50°. The value ranges from 6° to 9°. The value range is 0~5 rad / s. The value range is -20 to 0 rad / s 2 .

[0119] Considering the residual vibration energy, flexible impact, and risk of motion reversal of the curved Geneva mechanism, the objective function is defined. for:

[0120] (13)

[0121]

[0122] In the formula: , , and These are all weighting coefficients, used to balance the importance of each indicator in the optimization process; This is a global smoothness and flexibility index used to balance the degree of acceleration change during motion. The smaller the value, the smoother the change, indicating a gentler acceleration change and less impact. For speed control at critical positions (starting and ending points of the curve segment), the smaller the angular velocity at the critical position, the smaller the momentum change when entering or exiting the curve segment engagement, and the smaller the impact and vibration. Let be the angular velocity of the curved grooved wheel at the critical position j. Let M be the set of key locations, and M be the number of key locations. This is a peak suppression and oscillation control indicator to avoid repeated acceleration oscillations caused by excessively high polynomial order or improper parameters. The larger the peak acceleration, the greater the inertial force, and the worse the force on the curved groove wheel. Let be the angular acceleration of the curved grooved wheel. This represents the number of peak values ​​in the angular velocity curve of the curved groove wheel. This represents the number of peak values ​​in the angular acceleration curve of the curved groove wheel. It serves as a penalty factor to suppress multi-peak values, which are equivalent to frequent changes in angular velocity and angular acceleration, easily leading to resonance or fatigue. This is a boundary stability index derived from the boundary conditions of a fifth-degree polynomial and the requirement of no impact at the start and end points of the curve segment. If there are sudden acceleration changes at the start and end points of the curve segment, rigid or flexible impacts will occur, leading to collisions when entering and exiting the circular arc segment A0A1. This index ensures motion continuity and reduces impacts. and Let G be the angular velocity of the curved wheel at the starting point (point A1 when entering the curved section) and the ending point (point G) of the curved section A1G. and The angular accelerations at the start and end points of the curve segment are... This is the weighting coefficient between angular velocity and angular acceleration.

[0123] The genetic algorithm is set with a population size of 50, 100 iterations, a crossover probability of 0.9, and a mutation probability of 0.05. This embodiment uses the genetic algorithm to derive... , , and The optimal values ​​are 44.93°, 8.56°, 2.81 rad / s, and -2.32 rad / s, respectively. 2 Substituting the optimized motion law model of the curved groove wheel into equation (5), we obtain the optimized A1G parametric equation for the curved segment.

[0124] like Figure 8 Figures (a), (b), (c), and (d) show the curve comparison of the radial groove profile, angular displacement, angular velocity, and angular acceleration of the curved Geneva wheel before and after optimization by the genetic algorithm. They visually demonstrate that the radial groove profile of the optimized curved Geneva wheel is smoother (the value in the Y direction changes more smoothly with the X direction), and effectively reduces the peak values ​​of the angular velocity and angular acceleration of the optimized curved Geneva wheel mechanism.

[0125] like Figure 9 and Figure 10As shown, comparing the motion curves of the optimized curved Geneva mechanism of this invention with those of the traditional linear Geneva mechanism (where the curved segment A1G of the radial groove profile in this invention is a straight segment in the traditional linear Geneva mechanism), it can be seen that the traditional linear Geneva mechanism differs significantly in motion when the drive pin enters the straight segment, exits the straight segment, and the entire motion cycle ends (see...). Figure 10 At the three vertical positions within one motion cycle, the angular acceleration exhibits abrupt changes. However, the acceleration curve of the optimized curved Geneva mechanism of this invention only shows abrupt changes at the end of the entire motion cycle (the instant the drive pin exits the radial groove). The angular acceleration at the starting point, ending point, and point A1 when exiting the curve segment A1G remains constant (ensuring no abrupt change in angular acceleration at the starting point guarantees no abrupt change in angular acceleration at point A1 when exiting the curve segment). Furthermore, since the radial groove arc segments of both are identical, the angular acceleration values ​​at the moment of exiting the radial groove are the same. In the remaining stages, the acceleration curve of the optimized curved Geneva mechanism of this invention exhibits a continuous, abrupt, closed curve. Figure 9 and Figure 10 The comparison of motion curves verified that the optimized curved Geneva mechanism of the present invention eliminates the flexible impact at the moment of startup (the moment of starting rotation, rather than the moment of entering the arc segment) present in the traditional straight Geneva mechanism, thereby improving the seedling delivery accuracy and stability of the transfer device.

Claims

1. A low-impact rice seedling tray precision transfer device, comprising a longitudinal moving mechanism, a seedling box, a transverse moving mechanism, and a frame, characterized in that: The seedling box includes a box body, a slide rail, and a belt conveyor mechanism; the box body is arranged at an inclination, and the lower end of the box body forms a sliding pair with the horizontally arranged slide rail, which is fixed to the frame; the box body has two rectangular openings arranged at intervals, and a belt conveyor mechanism is provided at each of the two rectangular openings, with the input end of the belt conveyor mechanism being higher than the output end, the conveying direction of the belt conveyor mechanism being perpendicular to the slide rail, and the outer surface of the conveyor belt of the belt conveyor mechanism having multiple trapezoidal external teeth integrally formed and evenly distributed along the circumference, and multiple frustum protrusions are fixed between each two adjacent trapezoidal external teeth and are equidistantly arranged along the width direction of the conveyor belt; The lateral movement mechanism includes a drive shaft, a transmission shaft, striking rods, a double helical shaft, and a slider; the drive shaft, transmission shaft, and double helical shaft are all parallel to the slide rail and form a rotating pair with the mechanism; one end of the drive shaft is connected to the optical shaft section of one end of the double helical shaft through a gear pair, and the other end is connected to the transmission shaft through a chain drive mechanism; striking rods are fixed at both ends of the transmission shaft; the slider and the threaded section in the middle of the double helical shaft form a threaded pair and are fixed to the housing; The longitudinal moving mechanism includes a curved grooved wheel, a dial, a rocker arm, a planetary carrier, a first cylindrical gear, a ring gear carrier, a second cylindrical gear, a rotating shaft, and a return torsion spring. The rocker arm, planetary carrier, and ring gear carrier are arranged sequentially along the axial direction of the rotating shaft, which is located between two conveyor mechanisms and is coaxially fixed to the drive shafts of the two conveyor mechanisms. An integrally formed cylindrical column and a return torsion spring on the rocker arm are both fitted onto the rotating shaft, forming a rotating pair with the rotating shaft. The two ends of the return torsion spring are fixed to the cylindrical column and the rotating shaft, respectively. The planetary carrier is supported on the cylindrical column by a one-way bearing. The ring gear carrier is fitted onto the rotating shaft and fixed to the housing. The two coaxially fixed... Cylindrical gear two is placed inside the ring gear carrier and forms a revolute pair with the rotating shaft; cylindrical gear one and drive pin gear are both placed between cylindrical gear two and the ring gear carrier, and cylindrical gear one meshes with the internal teeth of cylindrical gear two near the planet carrier and the ring gear carrier, forming a revolute pair with the planet carrier; drive pin gear meshes with the internal teeth of another cylindrical gear two away from the planet carrier and the ring gear carrier, forming a revolute pair with the integrally formed connecting plate on the ring gear carrier; a dial is fixed on the drive pin gear, and two drive pins are fixed on the dial symmetrically arranged about the center of the dial; the curved grooved wheel is fixed to the rotating shaft.

2. The low-impact rice seedling tray precision transfer device according to claim 1, characterized in that: The slide rail is fixed to the frame by a number of support frames arranged at intervals.

3. The low-impact rice seedling tray precision transfer device according to claim 1, characterized in that: The belt conveyor mechanism includes a drive shaft, a driven shaft, conveyor rollers, and a conveyor belt. Both the drive shaft and the driven shaft form a rotating pair with the housing. Conveyor rollers are fixed on both the drive shaft and the driven shaft, and the two conveyor rollers are connected by the conveyor belt.

4. The low-impact rice seedling tray precision transfer device according to claim 3, characterized in that: The inner surface of the conveyor belt is provided with a plurality of integrally formed and circumferentially distributed internal teeth, and a plurality of integrally formed and circumferentially distributed trapezoidal external teeth on the conveyor roller mesh with a plurality of internal teeth on the inner side of the conveyor belt.

5. The low-impact rice seedling tray precision transfer device according to claim 1, characterized in that: The chain drive mechanism includes a driving sprocket, a chain, and a driven sprocket. The driving sprocket and the driven sprocket are fixed on the drive shaft and the transmission shaft, respectively, and are connected by the chain.

6. The low-impact rice seedling tray precision transfer device according to claim 1, characterized in that: A sleeve is fixedly fitted on the rotating shaft; a cylindrical tube and a reset torsion spring are both fitted on the sleeve, the cylindrical tube and the sleeve form a rotating pair, and the two ends of the reset torsion spring are fixed to the cylindrical tube and the sleeve; the second cylindrical gear and the sleeve form a rotating pair; the curved grooved wheel is fixed to the sleeve.

7. The method for transferring rice seedlings in pots using a low-impact rice pot-shaped blanket-like seedling precision transfer device according to any one of claims 1 to 6, characterized in that: Specifically as follows: Two potted blanket-shaped seedlings are placed on two conveyor belts with conveyor mechanisms. Each trapezoidal external tooth on each conveyor belt is engaged between two adjacent rows of seedlings at the bottom of the corresponding potted blanket-shaped seedling, and each frustum-shaped protrusion is engaged between two adjacent columns of seedlings. An external power source drives the shaft to rotate, which in turn drives the double helix shaft to rotate via a gear pair. This, in turn, drives the transmission shaft and each striking rod to rotate via a chain drive mechanism. As the double helix shaft rotates, the slider moves the box back and forth along the slide rail, causing each row of the two potted blanket-shaped seedlings placed on the box to be moved sequentially to the seedling picking position, thus performing the lateral feeding of the potted blanket-shaped seedlings. Whenever the slider moves to the end of the threaded section of the double helix shaft, one of the striking rods at the same end contacts the swing rod, pushing the swing rod to drive the cylinder to rotate clockwise. The cylinder drives the planetary carrier to rotate via a one-way bearing, and the planetary carrier drives the cylindrical gear one to rotate around the axis. Because the cylindrical gear one is close to the row The internal teeth of one cylindrical gear 2 on the planetary frame and the ring gear frame are meshed, causing the cylindrical gear 1 to rotate around its own central axis while rotating around the rotating shaft. This, in turn, drives the two cylindrical gear 2 to rotate. The cylindrical gear 2 away from the planetary frame meshes with the drive pin gear, thereby driving the drive pin gear and the dial to rotate. This causes a drive pin on the dial to enter a radial groove in the curved groove wheel, driving the curved groove wheel to rotate. The curved groove wheel drives the two drive shafts with conveyor mechanisms to rotate through the rotating shaft, causing the two conveyor mechanisms to work and convey the two potted blanket-shaped seedlings downward. When the striking rod disengages from the swing rod, the column cylinder reverses to its original position under the restoring force of the return torsion spring. At this time, the one-way bearing unlocks, the column cylinder no longer drives the planetary frame to rotate, and the two conveyor mechanisms stop working. At this time, the two potted blanket-shaped seedlings have been conveyed downward by one row of seedlings, performing the longitudinal seedling delivery work.

8. The method for transferring rice seedlings in pots using a low-impact, blanket-like seedling transfer device according to claim 7, characterized in that: The design process of the curved Geneva mechanism, consisting of a curved Geneva wheel, a dial, and two drive pins, is as follows: Let the rotation center of the dial be point O, the radius of the drive pin be r, the installation radius of the drive pin be r0, the rotation center of the curved grooved wheel be point O1, the center distance between the dial and the curved grooved wheel be R, and when the center of one tooth of the curved grooved wheel coincides with point O, the midpoint of the adjacent tooth behind it is point O2. Let the number of grooves on the curved grooved wheel be Z. Then the pitch angle of the curved grooved wheel is... The length of line segment OO2 is The initial and final positions of the driving pin are points A0 and B0, respectively, and point B0 is the midpoint of line segment OO2. Line segment O1B0 perpendicularly bisects line segment OO2. The radial groove profile of the curved Geneva wheel consists of an arc segment A0A1 and a curved segment A1G, with the curved segment A1G and the arc segment A0A1 being tangent at point A1. The theoretical center circle of the driving pin intersects the line segment OO1 at point E. Let the deepest point of the radial groove of the curved Geneva wheel be point G, which lies on a circle centered at point O1 and passing through point E. This is further defined by setting... The angle is determined, and the radius of the circle centered at point O1 and passing through point E is... The radial groove major diameter of the curved groove wheel is The radial groove minor diameter is ; Set dial to When the dial rotates at a constant speed and the center point of the driving pin moves along the arc segment A0A1, the angle of rotation of the dial is... With the curved pulley stationary, as the center point of the drive pin moves along the curved segment A1G, the angle of rotation of the dial relative to the line segment OA1 is... And drive the center point to reach At point 1, the curved groove wheel rotates. Then the center point of the drive pin moves in the opposite direction along the radial groove until the dial rotates 180° relative to its initial position, and the swivel wheel rotates to the indexing angle. Complete one vertical seedling delivery operation; The arc segment A0A1 is part of the theoretical center circle of the drive pin, while the curve segment A1G is solved in reverse according to the preset motion law, using the relative motion relationship between the dial angle and the curve groove wheel angle.

9. The method for transferring rice seedlings in pots using a low-impact, blanket-like seedling transfer device according to claim 8, characterized in that: The design process for curve segment A1G is as follows: Establish a Cartesian coordinate system for the dial with point O as the origin, the axis containing line segment OO1 as the x-axis, and the axis perpendicular to the x-axis as the y-axis. Establish a Cartesian coordinate system for the curved grooved wheel with point O1 as the origin, the axis containing line segment OO1 as the x-axis, and the axis perpendicular to the x-axis as the y-axis. The coordinates of point O in the Cartesian coordinate system of the curved grooved wheel are: Let the angle between line segment OA1 and the x-axis be such that the center point of the drive pin is at point A1. The local coordinates of the drive pin center point in the dial plane rectangular coordinate system are: (1) The absolute position vector of the drive pin center point in the Cartesian coordinate system of the curved grooved wheel plane is: (2) Let the rotation angle of the curved groove wheel be... Establish the coordinate transformation matrix: (3) The coordinate matrix of the center point of the drive pin relative to the curved grooved wheel is: (4) Substituting equation (2) into equation (4), we get: (5) Converting equation (5) to polar coordinates, the polar radius of the drive pin center point relative to the center of rotation of the curved groove wheel is... and polar angle They are respectively: (6) Construct a motion law model for a curved grooved wheel based on a fifth-order polynomial: (7) In the formula, The angle that the drive pin center point needs to rotate relative to the curved pulley from point A1 to point G; The time corresponding to the starting point of the curve segment. The function is the time corresponding to the termination point of the curve segment. Satisfying the boundary constraint set : (8) and （9） In the formula, , and These are the rotation of the center point of the drive pin. Then, the angular displacement, angular velocity, and angular acceleration of the curved grooved wheel; Boundary constraint set Substituting into equation (9), we get: (10) The motion law model expression for the curved Geneva wheel is: (11) in: Adjusted using a genetic algorithm , , and The motion law model of the curved groove wheel is optimized, and the optimized motion law model of the curved groove wheel is substituted into equation (5) to obtain the optimized A1G parameter equation of the curved segment.

10. The method for transferring rice seedlings in pots using a low-impact, blanket-like seedling transfer device according to claim 9, characterized in that: Adjusted using a genetic algorithm , , and The process of optimizing the motion law model of the curved Geneva wheel is as follows: Define design variables and determine the design variables. The range of values ​​for each parameter, and the design variables. for: (12) Define the objective function for: (13) In the formula: , , and All are weighting coefficients; As an indicator of global smoothness and flexibility; For key position speed control indicators, Let be the angular velocity of the curved grooved wheel at the critical position j. Let M be the set of key locations, and M be the number of key locations. It serves as a peak suppression and oscillation control indicator. Let be the angular acceleration of the curved grooved wheel. This represents the number of peak values ​​in the angular velocity curve of the curved groove wheel. This represents the number of peak values ​​in the angular acceleration curve of the curved groove wheel. As a penalty factor; As a boundary stationarity index, and Let A1G be the angular velocity at the start and end points of the curve segment. and Let A1G be the angular acceleration at the starting and ending points of the curve segment. This is the weighting coefficient between angular velocity and angular acceleration; Set the population size, number of iterations, crossover probability, and mutation probability, and derive the results using a genetic algorithm. , , and The optimal value is obtained and substituted into equation (11) to obtain the optimized motion law model of the curved groove wheel.

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