CN114793555A - Ditching depth adjustment mechanism based on shovel point pressure - Google Patents
Ditching depth adjustment mechanism based on shovel point pressure Download PDFInfo
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- CN114793555A CN114793555A CN202210584033.XA CN202210584033A CN114793555A CN 114793555 A CN114793555 A CN 114793555A CN 202210584033 A CN202210584033 A CN 202210584033A CN 114793555 A CN114793555 A CN 114793555A
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- 230000007246 mechanism Effects 0.000 title claims abstract description 15
- 238000000034 method Methods 0.000 claims abstract description 30
- 230000008569 process Effects 0.000 claims abstract description 11
- 238000012544 monitoring process Methods 0.000 claims abstract description 10
- 230000008859 change Effects 0.000 claims abstract description 9
- 238000012806 monitoring device Methods 0.000 claims abstract description 4
- 239000002689 soil Substances 0.000 claims description 22
- 230000001681 protective effect Effects 0.000 claims description 19
- 238000001914 filtration Methods 0.000 claims description 6
- 230000009471 action Effects 0.000 claims description 4
- 238000006243 chemical reaction Methods 0.000 claims description 4
- 238000005070 sampling Methods 0.000 claims description 3
- 230000001788 irregular Effects 0.000 claims description 2
- 230000035515 penetration Effects 0.000 claims 1
- 238000010899 nucleation Methods 0.000 abstract description 15
- 238000003971 tillage Methods 0.000 abstract description 9
- 238000005520 cutting process Methods 0.000 description 4
- 230000010365 information processing Effects 0.000 description 3
- 230000006872 improvement Effects 0.000 description 2
- 238000003466 welding Methods 0.000 description 2
- 230000002146 bilateral effect Effects 0.000 description 1
- 230000006378 damage Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
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- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
- A01C—PLANTING; SOWING; FERTILISING
- A01C5/00—Making or covering furrows or holes for sowing, planting or manuring
- A01C5/06—Machines for making or covering drills or furrows for sowing or planting
- A01C5/062—Devices for making drills or furrows
Abstract
The invention provides a real-time monitoring and adjusting mechanism for the ditching depth of a no-tillage seeding ditcher, which can monitor the ditching depth change condition of the ditcher in real time and make corresponding and timely adjustment when the ditching depth deviates from a proper depth range, thereby realizing the stability and consistency of the ditching depth in the no-tillage seeding process. The invention provides a novel ditching depth monitoring device, which utilizes a pressure sensor to detect the pressure change condition borne by a shovel tip in real time, and then uses a single chip microcomputer to control a motor to rotate positively and negatively to drive a shovel handle to lift through a straight-tooth gear rack so as to achieve the purpose of controlling the sinking depth of a ditcher.
Description
Technical Field
The invention belongs to the field of agricultural no-tillage seeding and ditching, and particularly relates to a real-time adjusting device for seeding and ditching depth.
Background
In recent years, the level of agricultural mechanization in China is continuously improved, wherein a no-tillage seeding machine is developing towards high speed, precision and automation as a key device for modern agricultural mechanization seeding. With the gradual maturity of the no-tillage seeding technology in China, the use of the no-tillage seeding machine greatly reduces the operation intensity of farmers, improves the operation environment and improves the working efficiency. However, as the no-tillage seeding technology in China starts late, although the no-tillage seeding technology develops rapidly in recent years, a lot of technical shortages still exist, such as the problems of uneven seeding grain distance, unstable seeding depth, inappropriate earthing pressure and the like, so that the seed emergence rate is always low, the ditching depth of a ditcher is the most critical factor influencing the unstable seeding depth, the ditching depth adjustment of the ditcher in China is almost manually adjusted currently, the adjusting process is complicated, and the workload is large; and the existing automatic profiling mechanism is mostly a single-point profiling or parallel four-bar mechanism, which has the characteristics of larger profiling lag or advance, and the accuracy and the response sensitivity of the adjusting mechanism are poorer. In addition, other devices, such as a 'ditcher ditching depth quick adjusting mechanism' with the patent number of CN200620023088.X, manually adjusting a locking nut to control a depth limiting wheel has the disadvantages of complicated operation, large workload and incapability of real-time adjustment. The 'automatic control system for the ditching depth of the disc type ditcher' with the patent number CN201010217322.3 adopts the hydraulic adjustment disc ditcher to limit the depth of the soil entering wheel, and oil leakage and liquid compressibility can influence the accuracy of the movement of an actuating element. Therefore, the furrow opener depth adjusting mechanism which is simple in structure, convenient to adjust and high in automation degree and accuracy is urgently needed.
Disclosure of Invention
The invention aims to provide a rapid ditching depth adjusting mechanism which can rapidly, accurately and automatically adjust the ditching depth to a high degree in a no-tillage seeding process.
The technical scheme adopted for achieving the purpose is as follows: the pressure sensor (11), the pressure sensor backing plate (10) and the pressure sensor protective shell (1) are connected through rivets (12) and are mounted on the furrow opener (2) together. The step motor (6) is connected with the straight-tooth gear (8) through a key, the step motor (6) is fixed on the motor fixing plate (9) through a bolt, the straight-tooth gear (8) is meshed with the straight-tooth rack (7), and the straight-tooth rack (7) is installed on the furrow opener shovel handle (3) through a bolt. The shovel handle (3) moves up and down along the guide pipe (5). The four furrow openers are connected together through a connecting frame (4) to simultaneously operate.
A ditching depth adjusting mechanism based on shovel tip pressure comprises a method for monitoring ditching depth by a pressure sensor, a signal processing combination method and a ditching depth closed-loop control, wherein the method for monitoring the ditching depth by the pressure sensor is that when a ditcher is in a working state, one end of a pressure sensor protective shell (1) is fixed on the pressure sensor (11), the other end of the pressure sensor protective shell is in direct contact with soil, the pressure sensor protective shell (1) is subjected to resistance of the soil in a running process to further press the pressure sensor (11), the pressure sensor is always under the action of pressure, and the ditching depth change condition of the ditcher can be obtained by detecting the pressure change of the pressure sensor (11). The signal processing and combining method comprises three links, wherein the first link is provided with a low-pass filter to eliminate regular vibration and power frequency interference, the second link is used for carrying out high-frequency acquisition on signals subjected to low-pass filtering, and the third link is used for converting acquired pressure signals (analog signals) into digital signals after a plurality of processes of sampling, holding, quantizing and encoding of an AD conversion module. The ditching depth closed-loop control method comprises the steps of firstly collecting a pressure value borne by a ditcher in real time, comparing the pressure value with a target pressure value after signal processing, and controlling the action of a stepping motor (6) in real time to realize the closed-loop control of the ditching depth.
Preferably, the information processing and combining method is used for filtering before signal acquisition so as to eliminate interference of radio frequency interference, electrostatic induction and the like on the signals of the pressure sensor.
Preferably, the information processing combination method performs high-frequency acquisition on the filtered signals.
Preferably, the information processing combination method performs AD conversion on the high-frequency acquired signal subjected to the filtering processing to convert the signal into a digital signal.
In the relative movement process of the soil and the part in the shovel body soil, the influence of lateral force (bilateral symmetry) is not considered, a two-surface wedge shape is formed along the section of the cutting edge, and the stress analysis in the working state is shown in the attached figure 7.
The blade of the shovel body generates cutting resistance in the soil cutting process, the upper surface and the lower surface are subjected to the sliding friction force of the soil, and the adhesion force of the upper surface and the cheek surface. The force applied to the furrow opener in the direction X, Y can be expressed as
PX=(S+F1+Fni)cosα+N1sinα-N2sinβ+F2cosβ+Fni-R1+Rside
+Nicosβ(1)
Py=N2cosβ+F2sinβ+(S+F1+Fni)sinα-N1cosα- G - Nisinβ(2)
The method comprises the following steps of obtaining a soil cutting resistance (N), F1 and F2, namely sliding friction force N of the upper surface and the bottom of a shovel body respectively, Fni, adhering force N of soil to the shovel body, N1 and N2, normal pressure N of the soil to the upper surface and the bottom of the shovel body, N-inertia impact force N, beta-soil destruction angle (DEG), G-furrow opener gravity N, R1-furrow opener inlet part working resistance N and Rside furrow opener cheek surface friction force N.
The stress of the pressure sensor is schematically shown in figure 8, the stress direction of the pressure sensor is perpendicular to the surface of the pressure sensor, and as indicated by arrows in the figure, when the stress exceeds the measuring range, the protrusion on the backing plate of the pressure sensor can prevent the pressure sensor from continuously deforming, so that the effect of protecting the sensor is achieved.
The pressure experienced by the pressure sensor from the shovel housing may be expressed as:
F =( Px + Py )cosα（3）
has the advantages that: the invention provides a real-time monitoring and adjusting device for the ditching depth of a ditcher, which can monitor the change condition of the ditching depth of the ditcher in real time and is convenient for a ditching depth adjusting system to carry out closed-loop control so as to achieve the consistency and the stability of the ditching depth.
And the ditching depth quick adjustment mechanism of the ditcher with the above structural characteristics has the following advantages: simple structure, quick convenience, the degree of accuracy height, very big improvement work efficiency, the uniformity of furrow opener ditching degree of depth is good, has very big improvement to the seeding rate of emergence.
The working principle of the invention is that when the furrow opener starts to work, the pressure sensor protective shell (1) firstly enters the soil and is in direct contact with the soil, when the furrow opener moves in the soil, the pressure sensor protective shell (1) in direct contact with the soil is subjected to the resistance of the soil, and then the pressure sensor (11) is pressed to deform, pressure signals obtained by the pressure sensor (11) are filtered by an AD converter and then converted into digital signals which are collected by a single chip machine and then compared with target pressure values, and then the straight-tooth gear (8) is driven to rotate forward and backward through the forward and backward rotation of the stepping motor (6) so as to drive the straight-tooth rack (7) connected with the shovel handle (3) to move up and down, thereby achieving the purpose of adjusting the lifting of the furrow opener. Wherein the shovel handle (3) moves up and down along the shovel handle guide tube (5).
FIG. 1 is a general schematic view of a ditching depth adjusting mechanism based on shovel tip pressure.
FIG. 2 is a schematic structural view of a ditching depth change monitoring device of the ditching depth adjusting mechanism based on the shovel tip pressure.
FIG. 3 is a schematic view of a depth adjusting device of the furrowing depth adjusting device of the furrow opener.
FIG. 4 is a schematic view of a fixed connection device of the ditching depth adjusting device of the ditcher.
Fig. 5 is a signal processing flow chart.
FIG. 6 is a schematic view of a ditching depth closed-loop control method.
FIG. 7 is a schematic view of a partial stress analysis in shovel soil.
Fig. 8 is a force diagram of the pressure sensor structure.
The device comprises a pressure sensor protective shell, a furrow opener shovel tip, a furrow opener shovel handle, a connecting frame, a guide pipe, a stepping motor, a straight-tooth rack 7, a straight-tooth gear 8, a stepping motor fixing plate 9, a pressure sensor backing plate 10, a pressure sensor 11 and a rivet 12, wherein the pressure sensor protective shell is arranged on the pressure sensor backing plate 1.
Detailed Description
A ditching depth adjusting mechanism based on shovel tip pressure comprises a ditching depth monitoring device, a depth adjusting device and a fixed connecting device. The device for monitoring the ditching depth is formed by connecting a shovel tip (2) of a ditcher, a pressure sensor base plate (10), a pressure sensor (11) and a pressure sensor protective shell (1) together through a rivet (13). The depth adjusting device is formed by connecting a stepping motor (6) with a straight-tooth gear (8) in a key connection mode, meshing a straight-tooth rack (7) with the straight-tooth gear (8), and connecting the straight-tooth rack (7) with a shovel handle (3) of the furrow opener through a bolt. The fixed connecting device consists of a shovel handle guide tube (5), a connecting frame (4) and a stepping motor fixing plate (9).
The present invention will be described in further detail with reference to the following examples and the accompanying drawings. A device for monitoring the ditching depth of the ditching depth adjusting device of the ditcher is sequentially connected with a pressure sensor protective shell (1), a pressure sensor (11), a pressure sensor base plate (10) and a ditcher shovel tip (2) through rivets (12) as shown in figure 2.
As shown in figure 3, the depth adjusting device of the ditching depth adjusting device of the ditcher is formed by connecting a stepping motor (6) with a straight-tooth gear (8) in a key mode, meshing a straight-tooth rack (7) with the straight-tooth gear (8), and connecting the straight-tooth rack (7) with a shovel handle (3) of the ditcher through a bolt.
The fixed connecting device of the ditching depth adjusting device of the ditcher is formed by welding a shovel shaft guide pipe (5) with a connecting frame (4) and welding a stepping motor fixing plate (9) with the shovel shaft guide pipe (5) as shown in figure 4.
The method for monitoring the ditching depth, the signal processing combination method and the ditching depth closed-loop control method of the pressure sensor are further described with reference to the attached drawings and the embodiment.
The method for monitoring the ditching depth by using the pressure sensor comprises the steps that the pressure sensor protective shell (1), the pressure sensor (11), the pressure sensor base plate (10) and a ditcher shovel tip (2) are connected with each other through a rivet (12) to form a structure shown in a figure 2, when the ditcher is in a working state, one end of the pressure sensor protective shell (1) is fixed on the pressure sensor (11), one end of the pressure sensor protective shell is in direct contact with soil, the pressure sensor protective shell (1) is subjected to resistance of the soil in the advancing process and then presses the pressure sensor (11), the pressure sensor (11) is always under the action of pressure, the pressure sensor base plate (10) is provided with a protection protruding block which prevents the pressure sensor (11) from being stressed to break through the maximum measuring range, the situation of the ditching depth can be obtained by monitoring the pressure change of the pressure sensor (11).
The signal processing combination method comprises three links, as shown in fig. 5, wherein the first link is provided with a low-pass filter to eliminate irregular vibration and power frequency interference of a machine in work, and the second link is used for performing high-frequency acquisition and mean filtering on a signal subjected to low-pass filtering to eliminate the influence of a random noise dynamic signal; the third step is that the collected pressure signal (analog signal) is converted into digital signal after sampling, holding, quantizing and coding processes of the AD conversion module.
As shown in FIG. 6, the ditching depth closed-loop control method provided by the invention comprises the steps of firstly collecting a pressure signal value of a pressure sensor in real time, comparing the signal value with a target pressure value after signal processing, and controlling the forward and reverse rotation of a stepping motor in real time to realize the closed-loop control of the ditching depth.
The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by the present specification, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.
Claims (8)
1. A furrow opener furrowing depth adjusting device based on shovel tip pressure is characterized by comprising a furrow opener shovel tip (2), a pressure sensor (11), a pressure sensor protective shell (1), a pressure sensor base plate (10), a stepping motor (6), a straight-tooth gear (8), a straight-tooth rack (7), a stepping motor fixing plate (9) and a furrow opener shovel handle guide pipe (5), wherein a furrow opener furrowing depth device single body is connected by a connecting frame (4) to jointly operate.
2. The ditcher shovel tip (2), the pressure sensor backing plate (10), the pressure sensor (11) and the pressure sensor protective shell (1) are connected together through a rivet (12) to form a ditching depth monitoring device of a ditcher ditching depth adjusting device according to claim 1.
3. The step motor (6) is connected with a straight-tooth gear (8) in a key way according to claim 1, a straight-tooth rack (7) is meshed with the straight-tooth gear (8), and the straight-tooth rack (7) is connected with a shovel handle (3) of a furrow opener through a bolt to form a depth adjusting mechanism of the furrow opener furrowing depth adjusting device.
4. According to the claim 1, when the singlechip receives the digital signal processed by the AD converter and then compares the digital signal with the target pressure value, the stepping motor is driven to rotate positively and negatively to adjust the lifting of the shovel handle of the furrow opener so as to adjust the soil penetration depth of the shovel tip of the furrow opener until the pressure value applied to the pressure sensor returns to the target pressure value range.
5. The shovel shaft guide tube (5), the connecting frame (4) and the stepping motor fixing plate (9) form a fixed connecting device of a ditching depth adjusting device of the ditcher according to claim 1, wherein the stepping motor (6) is fixedly connected with the stepping motor fixing plate (9) through bolts, and the shovel shaft guide tube (5) is welded on the stepping motor fixing plate (9).
6. The method for monitoring the ditching depth by the pressure sensor according to claim 1, wherein when the ditcher is in a working state, one end of the pressure sensor protective shell (1) is fixed on the pressure sensor (11), and the other end of the pressure sensor protective shell is in direct contact with soil, and the pressure sensor protective shell (1) is subjected to the resistance of the soil in the advancing process to further press the pressure sensor (11), so that the pressure sensor (11) is always under the action of pressure, and the ditching depth change condition of the ditcher can be obtained by detecting the pressure change of the pressure sensor (11).
7. The signal processing combination method according to claim 1 comprises three links, wherein the first link is provided with a low-pass filter to eliminate irregular vibration and power frequency interference of a machine in work, and the second link is used for performing high-frequency acquisition and mean filtering on the low-pass filtered signal to eliminate the influence of random noise dynamic signals; the third step is that the collected pressure signal (analog signal) is converted into digital signal after sampling, holding, quantizing and coding processes of the AD conversion module.
8. The closed-loop control method for the ditching depth according to claim 1, wherein a pressure signal value of a pressure sensor (11) is acquired in real time, and is compared with a target pressure value after signal processing, and the forward and reverse rotation of a stepping motor (6) is controlled in real time to realize the closed-loop control of the ditching depth.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202210584033.XA CN114793555A (en) | 2022-05-27 | 2022-05-27 | Ditching depth adjustment mechanism based on shovel point pressure |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202210584033.XA CN114793555A (en) | 2022-05-27 | 2022-05-27 | Ditching depth adjustment mechanism based on shovel point pressure |
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| CN114793555A true CN114793555A (en) | 2022-07-29 |
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| CN202210584033.XA Withdrawn CN114793555A (en) | 2022-05-27 | 2022-05-27 | Ditching depth adjustment mechanism based on shovel point pressure |
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| CN109729788A (en) * | 2019-02-28 | 2019-05-10 | 河南科技大学 | One inter-species kind seeder |
| CN111373909A (en) * | 2020-04-13 | 2020-07-07 | 中国农业机械化科学研究院 | Seeding depth control method and device for no-tillage seeding machine |
| CN113632621A (en) * | 2021-08-05 | 2021-11-12 | 黑龙江八一农垦大学 | Sowing depth control device and method based on depth limiting arm pressure and angle adjustment |
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2022
- 2022-05-27 CN CN202210584033.XA patent/CN114793555A/en not_active Withdrawn
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201007686Y (en) * | 2007-02-13 | 2008-01-16 | 中国农业大学 | Farm implement operation drag measuring device |
| CN101785386A (en) * | 2010-01-26 | 2010-07-28 | 中国农业大学 | Adjusting device used for sowing depth automatic control system |
| CN105103722A (en) * | 2015-08-12 | 2015-12-02 | 北京农业信息技术研究中心 | Seeding device and control method capable of adjusting depth of seeding |
| CN207354848U (en) * | 2017-07-04 | 2018-05-15 | 中国农业大学 | A kind of intelligence essence amount corn seeding monomer |
| CN208128849U (en) * | 2018-03-23 | 2018-11-23 | 中国农业科学院北京畜牧兽医研究所 | A kind of root guard top dressing device |
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| CN109729788A (en) * | 2019-02-28 | 2019-05-10 | 河南科技大学 | One inter-species kind seeder |
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Application publication date: 20220729 |