CN-122003988-A - Variable-stiffness impact type deep scarification mechanism based on electromagnetic control and control method

CN122003988ACN 122003988 ACN122003988 ACN 122003988ACN-122003988-A

Abstract

The invention discloses a variable-stiffness impact type subsoiling mechanism based on electromagnetic control and a control method, which relate to the technical field of agricultural machinery and comprise a frame, a control center, an energy device and a subsoiling mechanism assembly, wherein the subsoiling mechanism assembly is provided with a plurality of components, the deep scarification mechanism assemblies are all connected with the frame, the frame is provided with a mounting platform, the mounting platform is connected with an energy device, the energy device comprises a pneumatic power source and an electric power supply unit, the energy device is electrically connected with a control center, and the control center is connected with the upper end of the front part of the frame. According to the variable-stiffness impact type deep scarification mechanism and the control method based on electromagnetic control, the stiffness of the mechanism is changed by adjusting the current of the repulsive force magnetic ring so as to maintain self-excitation vibration, and high-frequency micro-amplitude impact or large-stroke chiseling is respectively realized by the push-pull electromagnet or the impact cylinder so as to adapt to soil environments with different hardness.

Inventors

GUO MINGZHUO
HAN YULIANG
WANG ZIYUAN
SUN DEZHI
LI YUNXI
HE XINGPING
ZHAO JIALE
CONG YONGJIAN
ZHUANG JIAN

Assignees

吉林大学

Dates

Publication Date: 20260512
Application Date: 20260413

Claims (10)

1. The variable-stiffness impact type subsoiling mechanism based on electromagnetic control is characterized by comprising a rack, a control center, an energy device and a subsoiling mechanism assembly, wherein a plurality of subsoiling mechanism assemblies are arranged and are connected with the rack; the subsoiler mechanism assembly comprises a front support arm, a transverse support arm, a main arm, a rear support arm and a shovel handle assembly, wherein the shovel handle assembly comprises a subsoiler body, a swinging base and a subsoiler tip, the subsoiler tip is fixedly connected with the swinging base, the swinging base is connected with the tail end of the subsoiler body, a push-pull electromagnet is arranged in the subsoiler body, and the swinging base is driven to swing and drive the subsoiler tip to generate slight impact; The main arm is hinged with the transverse support arm, a circumferential permanent magnet array is arranged on the front support arm, a repulsive magnetic ring which is opposite to the circumferential permanent magnet array at intervals is arranged at the top of the main arm, an electromagnet unit which is electrically connected with the control center is embedded in the repulsive magnetic ring, and the magnetic repulsive force between the repulsive magnetic ring and the circumferential permanent magnet array is changed by adjusting current, so that the equivalent rigidity of the main arm in swinging is changed; The lower end of the main arm is connected with the rear support arm, an impact cylinder is arranged at the rear of the rear support arm so as to drive the shovel handle assembly to generate large-stroke impact, and the lower part of the rear support arm is connected with the shovel handle assembly.
2. The variable-stiffness impact deep scarification mechanism based on electromagnetic control of claim 1 is characterized in that the circumferential permanent magnet array is formed by splicing a plurality of neodymium-iron-boron permanent magnets with fan-shaped cross sections along the circumferential direction, the circumferential permanent magnet array adopts the halbach array magnetizing technology, and the magnetizing directions of all the permanent magnet monomers are sequentially and rotatably arranged along the circumferential direction, so that the magnetic field orientation of the outer surface of one side of the circumferential permanent magnet array is enhanced, and the permanent magnet array and the repulsive force magnetic ring form an oriented magnetic repulsive force.
3. The variable-stiffness impact deep scarification mechanism based on electromagnetic control of claim 2 is characterized in that an outer column surface of the circumferential permanent magnet array is opposite to an inner concave surface of a repulsive force magnetic ring, a gap is arranged between the repulsive force magnetic ring and the circumferential permanent magnet array, the repulsive force magnetic ring is fixedly arranged on a top plane of a main arm through bolts, a main shaft hole is formed in the middle of the main arm, the main shaft hole is connected with a main pin shaft, the main pin shaft penetrates through a U-shaped fork lug arranged at the rear end of a transverse support arm, and the transverse support arm is hinged with the main arm.
4. The variable-stiffness impact deep scarification mechanism based on electromagnetic control of claim 3 is characterized in that a hollow cavity with a downward opening is arranged at the lower end of the main arm, the hollow cavity is connected with the rear support arm, a double-lug support is arranged at the back of the rear support arm and connected with the impact cylinder, the tail end of a piston rod of the impact cylinder is connected with a hinging seat through a pin shaft, the hinging seat is arranged at the rear part of the shovel handle assembly, and the front end of the shovel handle assembly is hinged with the lower end of the rear support arm.
5. The variable-rigidity impact type subsoiler mechanism based on electromagnetic control of claim 4 is characterized in that the push-pull electromagnet is fixedly arranged in an inner cavity at the tail end of the subsoiler body, a hinged support is arranged at the tail end of the subsoiler body and is connected with the upper end of a swing base, and a subsoiler tip is fixedly arranged on the upper surface of the swing base.
6. The variable stiffness impact deep scarification mechanism based on electromagnetic control of claim 5 is characterized in that a limiting block is arranged at the rear end of the main arm, a spring fixing arm is arranged at the lower part of the limiting block and connected with the main arm through a bolt, the spring fixing arm is of a U-shaped structure, the front end of the spring fixing arm is connected with one end of a limiting spring through a guide rod, and the other end of the limiting spring is abutted against the front support arm.
7. The variable-stiffness impact deep scarification mechanism based on electromagnetic control of claim 6 is characterized in that an angle encoder is coaxially arranged at the other end of the main pin shaft, and the angle encoder, the impact cylinder and the push-pull electromagnet are electrically connected with the control center.
8. The control method for the variable stiffness impact subsoiler based on electromagnetic control by using the device of claim 7 is characterized by comprising the following steps: s1, a control center controls a power supply to supply initial current to an electromagnet unit in a repulsive magnetic ring to generate a magnetic field with the same polarity as a circumferential permanent magnet array, so that a main arm is kept at an initial balance position; S2, the angle encoder collects rotation angle data of the main arm in real time and transmits the rotation angle data to the control center, and the control center calculates real-time vibration frequency and vibration amplitude of the main arm; and step S3, the control center compares the real-time vibration frequency and vibration amplitude with a preset soil resistance model and executes a grading control strategy.
9. The method for controlling the variable stiffness impact deep scarification mechanism based on electromagnetic control of claim 8, wherein the polarity of the magnetic field generated by the repulsive force magnetic ring in the step S1 is the same as the polarity of the magnetic field of the outer cylindrical surface of the circumferential permanent magnet array, and magnetic repulsive force is generated between the magnetic field and the magnetic field.
10. The method for controlling a variable stiffness impact subsoiler mechanism based on electromagnetic control according to claim 9, wherein the hierarchical control strategy in step S3 comprises: When the vibration frequency is judged to be in the effective resonance interval, the control center adopts a PID algorithm to adjust the current magnitude of the repulsive magnetic ring, so that the natural frequency of the mechanism changes along with the soil excitation frequency; When the vibration amplitude is smaller than a first preset threshold value and the frequency fluctuation variance is larger than a second preset threshold value, the control center keeps the current of the repulsive magnetic ring unchanged, and outputs high-frequency pulse voltage to the push-pull electromagnet to drive the subsoiling shovel tip to execute micro impact action; When the main arm backward inclination angle is larger than the third preset threshold value and the duration time exceeds the fourth preset threshold value, the control center outputs a trigger signal to the impact cylinder to drive the shovel handle assembly to execute large-stroke chiseling action.

Description

Variable-stiffness impact type deep scarification mechanism based on electromagnetic control and control method Technical Field The invention relates to the technical field of agricultural machinery, in particular to a variable-stiffness impact type deep scarification mechanism based on electromagnetic control and a control method. Background The vibration subsoiling technology has become one of the key technologies of modern protective cultivation because of the effective reduction of soil cutting resistance and improvement of soil disturbance effect. Particularly, the self-excited vibration deep loosening of the shovel body vibration is maintained by utilizing the periodical change of the soil cutting resistance, and compared with the forced vibration driven by a motor or hydraulic pressure, the self-excited vibration deep loosening device has the advantages of simple structure, no need of additional power source, obvious energy-saving effect and the like. However, the existing self-excited vibration subsoiling mechanism still has the following significant technical limitations in actual field operation: Firstly, the constant rigidity of the elastic element limits the working condition adaptability of self-excited vibration, and the existing self-excited vibration mechanism mostly adopts a mechanical spiral spring as an energy storage element, and the rigidity coefficient of the mechanical spiral spring is a fixed value. However, the physical characteristics of the field soil have high spatial variability, which means that the excitation frequency and amplitude of the external world to the shovel body are changed in real time. According to the vibration theory, an effective resonance drag reduction effect can be generated only when the natural frequency of the system is matched with the external excitation frequency. The design of fixed rigidity causes that the mechanism can not adjust the natural frequency of the mechanism according to the soil hardness in real time, so that the optimal operation range of the existing self-excited vibration subsoiler is very narrow. Second, a single reciprocating vibration mode lacks the ability to crush for high strength plow layers. The motion trail of the existing vibration subsoiler is mostly single longitudinal or arc reciprocating motion, and the soil breaking mechanism mainly depends on continuous shearing and extrusion. This approach works well in treating general soils, but in the face of hard plow layers or extremely hardened soils formed by years of deposition, the energy density is insufficient to overcome the extreme shear strength of the soil interior by simply relying on the micro-amplitude vibrations excited by the soil counter-force. The cutting edge has difficulty initiating the propagation of an initial crack in extremely hard soil due to the lack of a separate impact earth breaking mechanism with instantaneous high energy release characteristics. The existing high-frequency forced vibration can provide energy, but has high energy consumption and is easy to damage machines, and the phenomenon of 'floating shovel' or insufficient operation depth can often occur when the existing high-frequency forced vibration is used for hard soil, so that the deep soil structure cannot be effectively crushed. Disclosure of Invention The invention aims to provide a variable-stiffness impact subsoiler based on electromagnetic control and a control method, which solve the problems that the existing self-excited vibration subsoiler cannot adapt to the space variability of field soil due to constant stiffness, so that the drag reduction effect is unstable, and the working depth is insufficient or a floating shovel is caused by lack of an independent high-energy impact mechanism when encountering a hard plow bottom. In order to achieve the above purpose, the invention provides an electromagnetic control-based variable stiffness impact type subsoiling mechanism, which comprises a rack, a control center, an energy device and a subsoiling mechanism assembly, wherein a plurality of subsoiling mechanism assemblies are arranged, and are connected with the rack; the subsoiler mechanism assembly comprises a front support arm, a transverse support arm, a main arm, a rear support arm and a shovel handle assembly, wherein the shovel handle assembly comprises a subsoiler body, a swinging base and a subsoiler tip, the subsoiler tip is fixedly connected with the swinging base, the swinging base is connected with the tail end of the subsoiler body, a push-pull electromagnet is arranged in the subsoiler body, and the swinging base is driven to swing and drive the subsoiler tip to generate slight impact; The main arm is hinged with the transverse support arm, a circumferential permanent magnet array is arranged on the front support arm, a repulsive magnetic ring which is opposite to the circumferential permanent magnet array at intervals is arranged at the top of the main arm, an electromag