阅读说明：本技术 一种基于组合仿生抗粘附旋耕犁刀 (Based on bionical anti-adhesion rotary tillage coulter of combination ) 是由 于海跃 邵雷童 张子强 张邦成 张维伦 于 2020-12-07 设计创作，主要内容包括：本发明一种基于组合仿生抗粘附旋耕犁刀,属于农业机械领域,其目的在于改善旋耕犁刀在耕犁土壤时刀刃上粘附土壤的现象,从而降低旋耕犁刀在耕犁土壤时的阻力,本发明运用仿生学的思想,借鉴蜣螂体表独特的凸包结构以及具有特殊流体动力学特性的叶序排布形式,提出一种基于组合仿生抗粘附旋耕犁刀,按二维叶序排布形式在两个刀刃上布置仿生凸包结构,这些凸包结构改变耕犁时刀具的受力情况,从而达到减粘降阻的效果,延长使用寿命,减轻能量损耗,提高效率。(The invention discloses a combined bionic anti-adhesion rotary plough coulter, belongs to the field of agricultural machinery, and aims to improve the phenomenon that soil adheres to blades of a rotary plough coulter when the soil is ploughed, so that the resistance of the rotary plough coulter when the soil is ploughed is reduced.)

1. The utility model provides an anti-adhesion rotary tillage coulter based on combination bionical thought, its characterized in that two cutting edges of rotary tillage coulter all design and have combination bionic structure, draw reference to the convex closure structure of soil excavation animal dung beetle body surface promptly, the convex closure structure arrange according to the phyllotaxis form of arranging that has good even characteristic on the cutting edge.

For the adhesion T of the soil to the tool, i.e. the tensile strength of the bond of the soil to the tool in the direction perpendicular to the bonding plane:

in the formula

P is the tensile force of the soil acting on the cutter bonding surface in the vertical direction,

s is the contact area of the soil and the bionic cutter,

S₀is the contact area of the soil and the original cutter,

n is the number of convex hulls.

Under the condition that the tensile force P acting on the vertical direction of the combining surface of the cutter by soil is not changed, the convex hull structure increases the contact area between the cutter and the soil, the contact surface area of the bionic cutter is larger than that of the original cutter, and the adhesion force on the bionic cutter is smaller than that of the original cutter, so that the viscosity reduction effect is achieved.

The resistance force F when the cutter plows can be obtained by the following coulomb formula:

F＝P_CA+F_Ntanβ [2]

in the formula

P_CIn order to provide adhesion between the soil and the cutter,

a is the actual contact area of the soil and the cutter,

F_Nis the normal force on the tool interface,

beta is the friction angle between the soil and the cutter.

When the cutter plows soil, the soil is filled into the gap of the convex hull structure, so that the adhesion force P of the soil is ensured_CThe actual contact area A between the soil and the cutter is reduced, the friction angle beta between the soil and the cutter is changed by the arc convex hull structure, and the resistance F of the cutter is reduced, so that the resistance reduction effect is achieved.

The three-dimensional mathematical model of the phyllotaxis arrangement is as follows:

in the formula

r，z is the coordinate of the phyllotactic point in the three-dimensional mathematical model,

R₀is the radius of the plant stem where the phyllotaxis is located,

n is the ordinal number of the plant leaf sequence point,

alpha is the helix angle between two adjacent phyllotactic points.

Formula [3]α in ═ 2 π τ²Is a golden angle, and the phyllotaxy system obtained according to the golden angle arrangement has good uniformity, thereby ensuring that the cutter is stressed uniformly when ploughing.

Wherein the Fibonacci sequence {1, 1, 2, 3, 5, 8, 13, 21, …, F_k，F_k+1… } the ratio of two adjacent numbers can be:

2. a rotary tillage pears blade provided with a dung beetle surface imitated convex hull structure (5) on the blade edge of the rotary tillage pears blade according to claim 1, wherein the convex hull structure is an arc convex hull, the diameter of the arc convex hull is 1mm, and the height of the arc convex hull is 0.5 mm.

3. A rotary tillage coulter blade ridge wrap configuration as claimed in claim 1, arranged in a two dimensional pattern of plant phyllotaxy alignment with good uniformity characteristics, said two dimensional pattern of phyllotaxy alignment being a pattern of plant leaf helical alignment that spreads out along the side, said helical alignment having a divergence angle of gold α ═ 2 π τ²137.508 deg., whereinThe helical arrangement density depends on the phyllotactic coefficients h and R₀Where h is 1mm, R₀＝10mm。

4. A rotary tillage coulter blade ridge construction according to claim 1, arranged at the front 120mm portion of the front blade (3) and the side blades (4).

The technical field is as follows:

the invention relates to a plough cutter, in particular to a rotary tillage plough cutter based on combination of bionic adhesion resistance, and belongs to the field of agricultural machinery.

Background art:

the rotary plow is a tillage machine for completing tillage and harrowing operations, has excellent soil crushing capacity and land surface leveling capacity after tillage, can simultaneously crush stubbles in soil and is convenient for seeder operation, China is an agricultural big country with huge tillage area, traditional tillage tools are gradually replaced by modern mechanical tillage machines, the rotary plow becomes an important agricultural machine in China, the rotary plow blade is an important component of a rotary tillage pear machine, soil can adhere to the rotary plow blade in the tillage process of the rotary plow blade, the resistance of the blade in the tillage process is increased, the efficiency of the tillage is affected, the blade breaking phenomenon can occur even when the blade is too large in the tillage process, and the surface of the rotary plow blade needs to be regularly cleaned after long-time high-speed tillage plow work, so that the tillage process is hindered.

At present, the rotary tillage coulter generally achieves the effect of drag reduction of the tillage plough by improving the arc surface angle of the cutter, however, the problem of soil adhesion on the surface of the rotary tillage coulter is not well solved, and the improved rotary tillage coulter still needs to be cleaned regularly.

The invention introduces the concept of bionics into the design of the rotary tillage coulter, and finally enables the cutter to achieve the purpose of resisting soil adhesion, thereby reducing the resistance of the cutter in soil tillage and the vibration of the cutter, reducing the times of cleaning the surface of the cutter and improving the efficiency.

The invention content is as follows:

the invention aims to provide a combined bionic anti-adhesion rotary tillage coulter which is characterized in that a main blade and a side blade of the rotary tillage coulter are both designed with a combined bionic structure, namely a body surface convex hull structure for excavating animal dung beetles by using soil is used for reference, the convex hull structure is that the contact area of the blade and the soil is increased by using an arc convex hull, and the friction angle between the soil and a cutter is changed, so that the effects of viscosity reduction and resistance reduction are realized, and the convex hull structures are arranged on the blade according to a phyllotactic arrangement form with good uniform characteristics, so that the surface stress of the blade is uniform, and the vibration is reduced.

The technical scheme of the invention is as follows:

the invention designs a combined bionic erosion-resistant rotary tillage coulter by combining with the bionics thought, the rotary tillage coulter comprises a shank (1), a blade body (2), a main blade (3) and a side blade (4), bionic convex hull structures (5) are arranged on the rotary tillage coulter blades (3) and (4), the bionic convex hull structures are used for reference of dung beetle body surface convex hull structures, the convex hull structures change the distribution state of soil on the body surface acting force, and the blade surfaces of the coulters are arranged in a two-dimensional form with plant leaf sequences.

The design concept of the invention is from a soil excavation animal, namely dung beetle, wherein the dung beetle has a structure with excellent soil adhesion resistance after long-time evolution on the surface, the characteristic element of the surface structure of the dung beetle is extracted, namely, a convex hull structure, and the adhesion force T of soil to a cutter, namely the tensile strength of the adhesion position of the soil and the cutter in the vertical direction of the adhesion surface is as follows:

in the formula

P is the tensile force of the soil acting on the cutter bonding surface in the vertical direction,

s is the contact area of the soil and the bionic cutter,

S₀is the contact area of the soil and the original cutter,

n is the number of convex hulls.

Under the condition that the tensile force P acting on the vertical direction of the combining surface of the cutter by soil is not changed, the convex hull structure increases the contact area between the cutter and the soil, the contact surface area of the bionic cutter is larger than that of the original cutter, and the adhesion force on the bionic cutter is smaller than that of the original cutter, so that the viscosity reduction effect is achieved.

The resistance force F when the cutter plows can be obtained by the following coulomb formula:

F＝P_CA+F_Ntanβ [2]

in the formula

P_CIn order to provide adhesion between the soil and the cutter,

a is the actual contact area of the soil and the cutter,

F_Nis the normal force on the tool interface,

beta is the friction angle between the soil and the cutter.

When the cutter plows soil, the soil is filled into the gap of the convex hull structure, so that the adhesion force P of the soil is ensured_CThe actual contact area A between the soil and the cutter is reduced, the friction angle beta between the soil and the cutter is changed by the arc convex hull structure, and the resistance F of the cutter is reduced, so that the resistance reduction effect is achieved.

The micro-size design scheme of the anti-adhesion blade surface is determined by taking the adhesion of soil when the cutter works as a main index, the arrangement mode among convex hulls is derived from plant phyllotaxy spiral arrangement with good uniform characteristics, so that the stress on the cutter surface is more uniform, and the three-dimensional mathematical model of phyllotaxy arrangement is as follows:

in the formula

r，z is the coordinate of the phyllotactic point in the three-dimensional mathematical model,

R₀is the radius of the plant stem where the phyllotaxis is located,

n is the ordinal number of the plant leaf sequence point,

alpha is the helix angle between two adjacent phyllotactic points,

formula [3]α in ═ 2 π τ²Is a golden angle, and the phyllotactic system obtained according to the golden angle arrangement has good uniformity, so that the cutter is stressed uniformly when ploughed, wherein the phyllonacci number series {1, 1, 2, 3, 5, 8, 13, 21, …, F_k，F_k+1… } the ratio of two adjacent numbers can be:

meanwhile, the bionic convex hull structure changes the stress condition of the surface of the blade during plowing, the convex hull isolates the stress concentration point of the surface of the blade, and most of stress is concentrated on the top end of the convex hull, so that the adhesion force on the blade is reduced, the time interval for cleaning the cutter is prolonged, and the efficiency is improved.

According to the technical scheme provided by the invention, the bionic convex hull structure is an arc convex hull, and the divergence angle alpha of the phyllotactic arrangement is 2 pi tau²137.508 deg., wherein

The invention greatly reduces the phenomenon that soil is adhered to the surface of the rotary plow blade, reduces the resistance of the plow, reduces the times of cleaning the cutter, simultaneously reduces the vibration phenomenon of the cutter, improves the efficiency and quickens the plow progress.

Description of the drawings:

FIG. 1 is a structural view of a bionic rotary tillage coulter of the present invention

FIG. 2 is a schematic view of the convex hull arrangement on the blade edge of the intertillage plow shown in FIG. 1

FIG. 3 is an enlarged view of a portion of the blade of the cultivating plow shown in FIG. 1

The specific implementation mode is as follows:

the invention is further described below with reference to the accompanying drawings:

the bionic anti-adhesion rotary tillage coulter based on combination shown in figure 1 comprises a knife handle (1), a knife body (2), a main blade (3) and a side blade (4), wherein a convex hull structure (5) simulating dung beetle body surface anti-soil adhesion is arranged on the front 120mm part of the main blade (3) and the side blade (4), and the convex hull structure is designed to be circular-arc.

FIG. 2 is a schematic diagram of two-dimensional phyllotaxy arrangement of a bionic circular arc convex hull, wherein the phyllotaxy arrangement density depends on phyllotaxy coefficients h and R₀Where h is 1mm, R₀＝10mm。

Fig. 3 is a partial enlarged view of the bionic arc convex hull, wherein the machining radius R of the arc convex hull is 0.5mm, and the centroid distance D of the arc convex hull is 2 mm.