A manual and automatic intermittent amplitude modulation and frequency modulation electromagnetic vibration platform and control method

Abstract

The present invention discloses a manual-automatic intermittent amplitude modulation and frequency modulation electromagnetic vibration platform and control method, including a vibration seed plate, an exciter, a bracket, a chassis, a single-chip microcomputer acting as a signal generator, a power amplifier, a vibration sensor, and a photoelectric switch, a control device capable of automatic frequency modulation and amplitude modulation, and a leveling device. When the switch is in automatic gear, the photoelectric sensor gives the single-chip microcomputer high and low level signals, and the single-chip microcomputer generates a signal generator for the received high and low level generation circuit according to programming, generates a voltage signal of corresponding frequency, and adjusts the amplitude of the voltage signal according to programming at the same time, amplifies the voltage and current through the power amplifier, increases the power, drives the vibration platform to vibrate ideally, and the vibration sensor gives the vibration parameters of the vibration platform to the single-chip microcomputer. If the expected value is not reached, the single-chip microcomputer will increase the amplitude and frequency of the signal. When in manual gear, the single-chip microcomputer generates a voltage signal of corresponding frequency and amplitude by manually adjusting the left and right buttons and the up and down buttons to modulate the frequency and amplitude respectively.

Description

Technical Field

[0001] The present invention relates to the field of agricultural precision seeding, and in particular to an intermittent amplitude modulation and frequency modulation electromagnetic vibration platform and a control method thereof. Background Art

[0002] Sowing is an important technical link in the agricultural production process. In the planting mode of seedling raising and transplanting, the sowing and seedling raising technology is directly related to whether rice production can achieve high quality, high yield and high efficiency. The sowing device is the main means to realize mechanized precision sowing technology. The air suction vibration type precision and small amount sowing device can meet the unique agronomic requirements of super hybrid rice seedling raising, such as 2±1 seeds / hole, high seedling rate, and strong seedlings. At present, during the vibration process of the seed tray of the air suction vibration type precision and small amount sowing device, due to the use of mechanical vibration, it is found that under working conditions, the bracket shakes violently and the population vibrates unevenly. At the same time, the damping spring has different degrees of distortion and deformation. The smaller the deformation of the spring, the smaller the vibration intensity of the seed tray at this position is compared with other positions, and the population tends to gather in this direction during the vibration process. By correcting the spring, the degree of aggregation of the population during the vibration process can be reduced, but obvious aggregation will still occur after long-term vibration. On the other hand, the mechanical vibration table keeps vibrating. After long-term operation, the bracket shakes more violently, the vibration uniformity is greatly reduced, the noise becomes larger and larger, and the seeding qualification rate decreases. At present, the mechanical vibration table uses a motor to drive the crank connecting rod up and down to make the seed plate vibrate. The vibration frequency can only be adjusted by changing the motor speed, and the vibration amplitude is determined by the crank connecting rod structure and cannot be adjusted during the vibration process. The seeding machine on the market now uses an exciter to impact the seed plate to make the seeds in the seed plate empty for the adsorption of the seed suction plate. Rollers are used on both sides of the seed suction plate. The air pressure rod allows the seed suction plate to move back and forth from the assembly line to the vibration table. The rollers roll back and forth on the plate. The equipment loss is quite large, which greatly reduces the service life of the equipment. In order to achieve better sowing results, the uniform vibration of the seed plate during the vibration process is particularly important. The uniformity of vibration has a great influence on the boiling movement of the population, which in turn affects the seed absorption and operation effect of the seedling raising machine. The electromagnetic vibration table uses the suction action of the energized conductor to drive the table to vibrate up and down. Its vibration is gentler than that of the mechanical vibration table, which is conducive to the uniform vibration of the population. At the same time, the electromagnetic vibration table can change the amplitude and frequency of the vibration process by adjusting the electrical parameters, which is conducive to the design to achieve the requirements of uniform vibration, save energy consumption, and reduce equipment wear. Summary of the invention

[0003] In order to improve the seed absorption rate and sowing effect of the air vibration disc seeding machine, the present invention provides a manual and automatic intermittent amplitude modulation and frequency modulation electromagnetic vibration platform and control method. The electromagnetic device is mainly used in the air vibration disc seeding machine.

[0004] The present invention comprises a seed plate (1) capable of adding an air field, a vibrator (4), a base frame (6), a control device (7) capable of adjusting frequency and amplitude including a single chip microcomputer serving as a signal generator, a power amplifier plate, a photoelectric switch and a vibration sensor, and a vibration table leveling device (8). The vibrating seed plate is connected to the seed plate base frame by bolts and nuts through four fixing sheets on the side. Four springs (3) of the same specification are fixedly connected to the four corners of the vibrating seed plate and the vibration table bracket (5), and the bolts (2) play a vertical restraining role; the top of the vibrator table (4a) and the hollow cylindrical block (9) under the base frame form a coaxial center and are welded together, and the top rod provides the vibrating seed plate with power for reciprocating simple harmonic motion; the leveling device is installed at the bottom end of the bracket and fixed by bolts and nuts. The small round hole (5b) on the bracket cooperates with the level gauge on the controller to compensate for the defect of the vibration table being uneven due to uneven ground as the leveling device moves.

[0005] The manual-automatic intermittent amplitude modulation and frequency modulation electromagnetic vibration platform, using the exciter (4), can adjust the amplitude of the seed plate to 0-10mm. Figure 2 ) The bottom surface of the seed tray (1) is provided with small holes spaced 1 cm apart, so as to provide an upward force to the seeds when adding an air flow field in the future, so as to achieve a better "boiling" effect for the seeds.

[0006] The described manual-automatic intermittent amplitude modulation and frequency modulation electromagnetic vibration platform has spring bolts installed at the four corners of the bracket, and a bolt in the middle of the spring plays a vertical restraining role, limiting it to vertical movement. The spring bolts of the same specifications at the four corners reduce the amplitude of the vibrating seed plate, thereby playing a vibration reduction role.

[0007] The leveling device is used to compensate for the uneven ground surface.

[0008] There are four sets of leveling devices, namely leveling device 1, leveling device 2, leveling device 3, and leveling device 4. If the bubble of the level is not in the center, the platform is not level. If any column is unstable, you can increase or decrease the length of the column through this leveling device until the vibration table is stable and the level reaches a level effect.

[0009] The manual and automatic intermittent amplitude modulation and frequency modulation electromagnetic vibration platform has a control device (7) on the side of the bracket, including a signal generator plate, a power amplifier plate, a vibration sensor on the vibration table, and a photoelectric switch a and a photoelectric switch b on the assembly line and the vibration table bracket, which can manually and automatically control the frequency and amplitude of the vibration plate vibration, adjust the output power of the power amplifier, and realize the vibration of the vibration table. Photoelectric switches a, b, and vibration sensors are connected to the single-chip microcomputer interface. The single-chip microcomputer, power amplifier plate, and exciter, which act as signal generators, are connected in series through wires to give the exciter a voltage signal. The single-chip microcomputer generates a circuit to generate a signal generator for the received high and low level signals according to programming to generate a voltage signal of corresponding frequency and amplitude, which is amplified by the power amplifier plate to control the exciter and make the vibration table vibrate. The single-chip microcomputer determines whether the expected value is reached based on the amplitude and frequency values ​​of the vibration sensor. If not, the signal amplitude and frequency are automatically adjusted.

[0010] The described manual-automatic intermittent amplitude modulation and frequency modulation electromagnetic vibration platform uses a single-chip microcomputer to make a signal generator, combined with photoelectric switches a, b, and vibration sensors, which can realize manual and automatic control of the exciter. When the switch is in automatic gear, photoelectric switches a and b give high and low level signals to the single-chip microcomputer. The single-chip microcomputer receives different high and low levels of photoelectric switches a and b according to the programming. The signal generator generates a voltage signal of the corresponding frequency, and adjusts the amplitude of the voltage signal according to the programming to generate a sinusoidal signal that meets the needs. When the manual-automatic switch is in manual gear, the left and right buttons and the up and down buttons can be used to adjust the frequency and amplitude respectively. The single-chip microcomputer generates a voltage signal of the corresponding frequency and amplitude according to the programming to generate a sinusoidal signal that meets the needs. The type of wave generated, the frequency and amplitude of the wave will be displayed on the liquid crystal, which is convenient for further understanding of the situation of the signal generator generating the signal.

[0011] The manual-automatic intermittent amplitude modulation and frequency modulation electromagnetic vibration platform uses multiple triodes to form a power amplifier, uses a common emitter amplifier circuit to increase the voltage, uses a common collector amplifier circuit to increase the current, and uses a sliding rheostat to control the amplified voltage and current. When the switch is in automatic mode, the sliding rheostat is at an ideal value and remains stationary. When the voltage signal from the signal generator is transmitted, the voltage and current are amplified to increase the output power to the exciter, allowing the exciter to vibrate. When the switch of the signal generator is in manual mode, when the output power of the power amplifier is insufficient, the resistance value can be changed by sliding the sliding piece of the sliding rheostat to amplify the voltage and current, and change the output power so that the exciter can achieve a good vibration effect.

[0012] The manual intermittent amplitude modulation and frequency modulation electromagnetic vibration platform and control method are characterized in that:

[0013] When the switch of the signal generator is in the automatic gear, intermittent automatic amplitude modulation and frequency modulation can be realized. During the work initialization, the single-chip microcomputer generates a low-frequency, low-amplitude sinusoidal signal with energy-saving parameters a (mm) and b (hz). Through the power amplifier, the vibrator is vibrated in an energy-saving state. The seed suction disc is located above the seedling tray of the assembly line. The photoelectric switch a detects the obstruction of the seed suction disc. The signal generated by the single-chip microcomputer remains unchanged. When the seed suction disc leaves the assembly line, the photoelectric switch a receives the signal that the seed suction disc has left. The photoelectric switch a prepares the single-chip microcomputer with a low-level signal in advance. The single-chip microcomputer gradually increases the voltage signal at a frequency and amplitude of 0.5s1hz.1mm according to the programming. The voltage and current are amplified by the power amplifier to increase the output power to the vibrator. Before the seed suction disc reaches the top of the vibration table, it increases to the ideal vibration parameters A (mm) and B (hz). The vibration sensor sends the vibration parameters of the vibration table to the single-chip microcomputer. If it does not reach the expected value, the single-chip microcomputer will increase the amplitude and frequency of the signal. When the seed-absorbing disc reaches the top of the seed-absorbing disc and is ready to absorb seeds, the photoelectric switch b detects that the obstruction of the seed-absorbing disc is at a high level, and the signal generated by the single-chip microcomputer remains unchanged, maintaining the voltage signal of the ideal frequency and amplitude, maintaining the power output of the power amplifier, allowing the exciter to maintain the ideal vibration parameters, allowing the seeds in the seed disc to vibrate evenly, facilitating the adsorption of the seed-absorbing disc and improving the seed-absorbing effect of the seed-absorbing disc. When the seed-absorbing disc finishes absorbing seeds and leaves the vibration table, the photoelectric switch b receives the signal that the seed-absorbing disc has left, and gives the single-chip microcomputer a low-level signal. The single-chip microcomputer receives the low-level signal of the photoelectric switch b according to the programming. The single-chip microcomputer gradually increases the voltage signal at a rate of 2hz / 1s and an amplitude of 2mm / s according to the programming, and amplifies the voltage and current through the power amplifier, reducing the output power to the exciter to the energy-saving parameters a (mm) and b (hz), so as to achieve the effect of not affecting the work of the seed-absorbing disc and saving energy, and at the same time prolonging the service life. When the seed suction tray reaches above the seedling tray of the assembly line, the photoelectric switch a detects the obstruction of the seed suction tray and gives a high-level signal to the microcontroller. The signal generated by the microcontroller remains unchanged, and the power amplifier puts the exciter in an ideal energy-saving state, thereby extending the service life of the vibration table.

[0014] When the switch is in manual mode, you can adjust the frequency and amplitude of the signal generator to achieve the desired parameters, transmit the signal to the power amplifier to amplify the voltage and current, and output the ideal power to the exciter, so that the vibration table can continue to vibrate ideally. If you feel that the output power needs to be increased, you can adjust the slider of the power amplifier's sliding rheostat, adjust the resistance value, and change the amplified voltage and current to increase the output power. The vibration sensor sends the vibration parameters of the vibration table to the microcontroller. If it does not reach the expected value, you can increase the amplitude and frequency of the signal by pressing the button.

[0015] Beneficial effects of the present invention:

[0016] 1. The present invention can achieve uniform vibration of the vibrating seed plate during the vibration process, thereby improving the uniformity of the seed population boiling effect.

[0017] 2. The present invention can also adjust the vibration frequency and amplitude of the vibrating seed disk, and can intermittently adjust different vibration frequencies and amplitudes for different seed thicknesses and different working times. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0019] Figure 2 This is a schematic diagram of the pore structure in the center of the seed tray;

[0020] Figure 3 Schematic diagram of the seed tray structure;

[0021] Figure 4 The schematic diagram of the chassis;

[0022] Figure 5 This is a schematic diagram of the assembly of the base frame and the seed tray;

[0023] Figure 6 It is a schematic diagram of the assembly of bolts, springs and bearing fixed ends;

[0024] Figure 7 This is a schematic diagram of the assembly of the seed tray, base, and bracket;

[0025] Figure 8 Schematic diagram and assembly diagram of the balancing structure;

[0026] Fig. 9 It is a schematic diagram of the center frame of the bracket;

[0027] Fig.10 This is a schematic diagram of the vibration exciter assembly;

[0028] Fig.11 is a schematic diagram of the device location of the controller;

[0029] Fig.12 A schematic diagram of the controller composition;

[0030] Fig.13 This is the main program flow chart of the frequency and amplitude modulation vibration control of the seed plate;

[0031] Fig.14 is a circuit diagram of a power amplifier;

[0032] In the figure: 1 is a seed plate, 1a is a small hole for air flow, and 1b is a first fixed sheet;

[0033] 2 is a bolt, 2a is the bearing fixing end;

[0034] 3 is a spring;

[0035] 4 is a vibration exciter, 4a is a vibration exciter table, 4b is a vibration exciter top rod, and 4c is a vibration exciter base;

[0036] 5 is a bracket; 5a is the center bracket of the vibration table, and 5b is a small round hole (through the front and back);

[0037] 6 is a base frame, 6a is a second fixing sheet, and 6b is a third fixing sheet;

[0038] 7 is a control device, 8 is a leveling device;

[0039] 9 is a hollow cylindrical block, 9a is a fourth fixed sheet, and 9b is a hollow cylinder; DETAILED DESCRIPTION

[0040] The present invention proposes a manual-automatic intermittent amplitude modulation and frequency modulation electromagnetic vibration platform and control method, which are used in a pneumatic vibration precision seeding machine. When the seed suction disc absorbs seeds, the seeds in the seed tray of the vibration table can be vibrated evenly, which is convenient for the seed suction disc to adsorb and sow the seeds into the seedling tray. The energy-saving effect can be achieved during the time period when the seed suction disc leaves the seed tray. The existing mechanical vibration table cannot be adjusted during the working process. Continuous vibration will cause the vibration table to have a high failure rate and waste resources. In view of these problems, the present invention designs a manual-automatic intermittent amplitude modulation and frequency modulation electromagnetic vibration platform and control method. The electromagnetic vibration device includes a vibration seed tray that can add an air field, a spring bolt, an exciter, a bracket, a chassis, a single-chip microcomputer that acts as a signal generator, a power amplifier plate, a vibration sensor, and a photoelectric switch that can automatically adjust the frequency and amplitude, and a leveling device. When the manual-automatic switch is in automatic gear, the photoelectric sensor sends high and low level signals to the single-chip microcomputer. The single-chip microcomputer generates a signal generator for the received high and low level according to the programming, generates a voltage signal of the corresponding frequency, and adjusts the amplitude of the voltage signal according to the programming. The power amplifier amplifies the voltage and current to increase the power and drive the vibration table to vibrate ideally. The vibration sensor sends the vibration parameters of the vibration table to the single-chip microcomputer. If the expected value is not reached, the single-chip microcomputer will increase the amplitude and frequency of the signal. When the manual-automatic switch is in manual gear, it can be adjusted manually by pressing the left and right buttons and the up and down buttons to adjust the frequency and amplitude respectively. The single-chip microcomputer generates a voltage signal of the corresponding frequency and amplitude according to the programming. The power amplifier amplifies the voltage and current to increase the power and drive the vibration table to vibrate ideally. The resistance value of the sliding rheostat of the power amplifier plate can also be adjusted to amplify the voltage and current, increase the power, and make the vibration table vibrate more. The vibration sensor sends the vibration parameters of the vibration table to the single-chip microcomputer. If the expected value is not reached, the amplitude and frequency of the signal can be increased by pressing the button. The electromagnetic vibration table uses the attraction of the energized conductor to drive the table to vibrate up and down. Its vibration is gentler than that of the mechanical vibration table, which is conducive to the uniform vibration of the population. At the same time, the electromagnetic vibration table can change the amplitude and frequency of the vibration process by adjusting the electrical parameters to achieve energy saving and extend the service life. The leveling device combined with the spirit level can easily solve the problem of the vibration table not being level, resulting in the seed plate vibrating non-vertically.

[0041] The present invention will be further described below in conjunction with the accompanying drawings.

[0042] like Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 , Fig. 9 , Fig.10 , Fig.11As shown, it is a schematic diagram of the overall mechanism of the electromagnetic vibration device and some mechanism parts. The electromagnetic vibration device includes: a seed plate 1, an exciter 4, a base frame 6, a control device 7, and a leveling device 8. The vibrating seed plate is connected to the base frame 6 fixed sheet 6a through four side fixed sheets with bolts and nuts, and the base frame 6 is connected to the fourth fixed sheet 9a of the base frame hollow cylindrical block 9 through two sheets with bolts and nuts. Four springs 3 and bolts 2 of the same specification are fixedly connected to the seed plate 1 and the four corners of the vibration table bracket 5. The bolts 2 play a vertical restraining role in the middle of the spring 3; the top of the exciter push rod 4b of the exciter 4 forms a coaxial center with the hollow cylinder 9 under the base frame 6, welded together, and the bottom is fixedly connected to the vibration table bracket 5a through bolts and nuts. The push rod provides power for the reciprocating simple harmonic motion of the vibrating seed plate; the adjustable stability device is installed at the bottom end of the bracket 5 and fixed by bolts and nuts. The small round hole 5b on the bracket cooperates with the level gauge on the controller to make up for the defect of the vibration table being not level due to uneven ground as the leveling device moves.

[0043] like Figure 2 In the middle of the seed tray 1, there is an array of small holes 1a with a diameter of 2mm and a spacing of 1cm for air field circulation, so that in the future, if the vibration does not achieve the ideal effect, air flow can be added to form an air flow field to assist the seeds to reach the "boiling" state.

[0044] like Figure 3 , Figure 4 The fixed sheets are distributed at the four corners of the seed tray. The first fixed sheet 1b, the second fixed sheet 6a, the third fixed sheet 6b, and the fourth fixed sheet 9a are fixed by bolts and nuts to achieve the effect of connecting the seed tray 1 with the base frame 6, and the base frame 6 with the hollow cylindrical block 9, to prevent the third fixed sheet 6b directly welded on the base frame from not being vertical enough, resulting in unstable vibration of the seed tray. The base frame and the hollow cylinder can be flexibly adjusted, so that the table of the exciter 4 can enter the hollow cylinder and vertically support the seed tray, which is also convenient for later replacement. The final effect is as follows Figure 5 shown.

[0045] like Figure 6 , spring 3 and bolt 2, their axes are in the same straight line, spring 3 is outside bolt 2, and the central axes of the two are in the same line. Spring 3 is pressed by bearing fixed end 2a to fix spring 3. The fixed end is welded to the vibration table bracket, and the other end of bolt 2 is welded to the vibration table bracket. The tail of bolt 2 is sleeved inside the bearing fixed end 2a. The final effect is as follows Figure 6 shown.

[0046] like Figure 7 At the bottom of the vibration table bracket 5, each bracket has a small round hole 5b for fixing the leveling device. The bolt 2 is inserted so that the vibration table bracket will not be displaced vertically.

[0047] like Figure 8Bolt 2 is put through the vibration table leveling device 8, and then through the small round hole 5b on the bracket, and is tightened with a nut. If the ground is uneven and causes one of the four columns to shake, bolt 2 can be moved in the groove of the vibration table leveling device 8 to lengthen the column to achieve the effect of stabilizing the vibration table without shaking, which indirectly solves the problem of the vibration table not being level and causing the seed plate to vibrate non-vertically. Add a level meter above the control device as a reference.

[0048] like Fig. 9 , Fig.10 The vibrator base 4c is fixedly connected to the center bracket 5a of the vibration table by bolts and nuts at the bottom of the center of the seed tray. The distance between the upper surface of the vibration table center bracket 5a and the lower surface of the seed tray in a stable state after assembly is equal to the original height of the vibrator. The table of the vibrator is against the bottom of the seed tray, causing the seed tray to vibrate. The springs at the four corners play a supporting and shock absorbing role. The four bolts in the sleeve constrain the seed tray to vibrate in the vertical direction without offset, reducing the influence of irregular vibration on the movement of the seed tray.

[0049] like Fig.11 The frequency-adjustable amplitude-modulated control device 7 is installed on the right side of the vibration table bracket 5 for easy adjustment and control. The control device is mainly composed of a single-chip microcomputer acting as a signal generator, a power amplifier plate, a photoelectric switch and a vibration sensor. The vibration table bracket 5 and the assembly line are respectively equipped with a photoelectric sensor a and a photoelectric sensor b. The photoelectric sensor a detects whether the seed suction disc reaches the vibration table so as to adjust to the ideal vibration parameters. The photoelectric sensor b detects whether the seed suction disc reaches the assembly line so as to adjust to the energy-saving vibration parameters.

[0050] like Fig.12 There is a controller on the side of the vibration table bracket 5, including a signal generator plate, a power amplifier plate, a vibration sensor on the vibration table, and photoelectric switches a and b on the assembly line and the vibration table bracket 5, which can manually and automatically control the frequency and amplitude of the vibration of the vibration disk, adjust the output power of the power amplifier, and realize the vibration of the vibration table. Photoelectric switches a, b, and vibration sensors are connected to the single-chip microcomputer interface. The single-chip microcomputer, power amplifier plate, and exciter, which act as signal generators, are connected in series through wires to give the exciter a voltage signal. The single-chip microcomputer generates a circuit to form a signal generator for the received high and low level signals according to the programming to generate a voltage signal of the corresponding frequency and amplitude, which is amplified by the power amplifier plate to control the exciter to make the vibration table vibrate. The single-chip microcomputer determines whether the expected value is reached based on the amplitude and frequency values ​​of the vibration sensor, and automatically adjusts the signal amplitude and frequency if it is not reached.

[0051] like Fig.13, use a single-chip microcomputer to make a signal generator, combined with photoelectric switches a, b, and vibration sensors, you can achieve manual and automatic control of the exciter. When the switch is in automatic mode, photoelectric switches a and b give high and low level signals to the single-chip microcomputer. The single-chip microcomputer generates a voltage signal of the corresponding frequency according to the programming of the different generation circuits of the high and low levels of the photoelectric switches a and b, and adjusts the amplitude of the voltage signal according to the programming to generate a sine signal that meets the needs. When the manual-automatic switch is in manual mode, you can use the left and right buttons and the up and down buttons to adjust the frequency and amplitude respectively. The single-chip microcomputer generates a voltage signal of the corresponding frequency and amplitude according to the programming to generate a sine signal that meets the needs. The type of wave generated, the frequency and amplitude of the wave will be displayed on the LCD, which is convenient for further understanding of the signal generated by the signal generator. Use multiple triodes to make a power amplifier, use the common emitter amplifier circuit to increase the voltage, and the common collector amplifier circuit to increase the current. Use the sliding rheostat to control the amplified voltage and current. When the switch is in automatic mode, the sliding rheostat is at an ideal value and remains stationary. When the voltage signal from the signal generator is transmitted, the voltage and current are amplified to increase the output power to the exciter, so that the exciter vibrates. When the switch of the signal generator is in manual mode, if the output power of the power amplifier is not enough, the resistance value can be changed by sliding the sliding piece of the rheostat to amplify the voltage and current, and change the output power so that the exciter can achieve a good vibration effect. When the switch of the signal generator is in automatic mode, intermittent automatic amplitude modulation and frequency modulation can be realized. During work initialization, the single-chip microcomputer generates a low-frequency, low-amplitude sinusoidal signal with energy-saving parameters a (mm) and b (hz). Through the power amplifier, the exciter is vibrated in an energy-saving state. The seed suction tray is located above the seedling tray of the assembly line. The photoelectric switch a detects the obstruction of the seed suction tray, and the signal generated by the single-chip microcomputer remains unchanged. When the seed suction tray leaves the assembly line, the photoelectric switch a receives the signal that the seed suction tray has left. The photoelectric switch a prepares the single-chip microcomputer with a low-level signal in advance. According to the programming, the single-chip microcomputer gradually increases the voltage signal at a rate of 2hz / 1s and an amplitude of 2mm / s. The voltage and current are amplified by the power amplifier to increase the output power to the exciter. Before the seed suction tray reaches the top of the vibration table, it increases to the ideal vibration parameters A (mm) and B (hz). The vibration sensor sends the vibration parameters of the vibration table to the single-chip microcomputer. If the expected values ​​are not reached, the single-chip microcomputer will increase the amplitude and frequency of the signal. When the seed suction tray reaches the top of the seed tray and is ready to absorb seeds, the photoelectric switch b detects that the cover of the seed suction tray is at a high level, the signal generated by the single-chip microcomputer remains unchanged, the voltage signal with ideal frequency and amplitude is maintained, the power output of the power amplifier is maintained, the exciter maintains ideal vibration parameters, and the seeds in the seed tray vibrate evenly, which is convenient for the seed suction tray to adsorb and improve the seed suction effect of the seed suction tray.When the seed-absorbing disc finishes absorbing seeds and leaves the vibration table, the photoelectric switch b receives the signal that the seed-absorbing disc has left and gives a low-level signal to the single-chip microcomputer. The single-chip microcomputer receives the low-level signal from the photoelectric switch b according to the programming. The frequency of the single-chip microcomputer is 2hz / 1s and the amplitude is 2mm / s. The voltage and current are amplified by the power amplifier, and the output power to the exciter is reduced to the energy-saving parameters a (mm) and b (hz), so as not to affect the work of the seed-absorbing disc and save energy. At the same time, the service life can be extended. When the seed-absorbing disc reaches the top of the seed-raising disc on the assembly line, the photoelectric switch a detects the obstruction of the seed-absorbing disc and gives a high-level signal to the single-chip microcomputer. The signal generated by the single-chip microcomputer remains unchanged. After the power amplifier, the exciter is in an ideal energy-saving state, which extends the service life of the vibration table. When the switch is in manual mode, the frequency and amplitude of the signal generator can be adjusted to achieve the desired parameters, and the signal is transmitted to the power amplifier to amplify the voltage and current, and the ideal power is output to the exciter, so that the vibration table can continue to vibrate ideally. If the output power needs to be increased, the slider of the sliding rheostat of the power amplifier can be adjusted to adjust the resistance value, change the amplified voltage and current size, and increase the output power. The vibration sensor sends the vibration parameters of the vibration table to the microcontroller. If it does not reach the expected value, the amplitude and frequency of the signal can be increased by pressing the button.

[0052] like Fig.14 , when U i When it is not 0, there will be a dynamic base current i in the input circuit based on the static circuit. b , correspondingly, a dynamic current i is generated in the output circuit c , collector resistance R c (R3) converts the change of the collector junction current into a change of voltage, so that the tube voltage drop U ce The change in the tube voltage drop is the output dynamic voltage U0, thereby achieving voltage amplification. i’ , and then participate in the common collector amplifier circuit, replacing U in the common collector amplifier circuit i , after being amplified by the Darlington circuit, the designed input resistance is large and the output resistance is small, achieving the effect of only amplifying the current.

[0053] The common-collector amplifier circuit is equivalent to a resistor, and the dynamic analysis theoretical amplification formula of the common-emitter amplifier circuit is as follows:

[0054]

[0055] R L’ =R3 / / {R5+[(1+β2)(1+β3)(1+β4)R6]}

[0056]

[0057] Where R L’ is the resistance of all parallel devices between R3 and the load, r bb’ is the transistor base resistance, β is the transistor gain, R e is the emitter resistance of the basic common emitter amplifier circuit, r be is the equivalent resistance of the emitter junction of transistor Q1, I CQ is the emitter current of the basic common emitter amplifier circuit, U T为 Temperature-voltage equivalent, substituting the data into the formula, the theoretical and actual measured amplification factors are very close.

[0058] The amplification formula of the common collector amplifier circuit theory dynamic analysis is as follows:

[0059]

[0060] Where β' is the magnification, that is, β2×β3×β4, R b’ The collector resistance of the common collector amplifier circuit is R5, r be is the equivalent resistance of the emitter junction of transistors Q2, Q3, and Q4, Re' is the resistance R6+R L The value of R b′ +r be The value is much smaller than (1+β′)R e′ , then A u2 ≈1, which is U 0’ ≈U i’ , U 0’ is the output voltage of the common-collector amplifier circuit, U i’ is the input voltage of the common-collector amplifier circuit, so the amplification factor of the common-collector amplifier circuit is approximately equal to 1.

[0061]

[0062] I b’ is the base current of the common-collector amplifier circuit, I e’ is the emitter current of the common-collector amplifier circuit

[0063] In the power amplifier circuit, the final amplified current is related to the internal resistance of the load. If the frequency increases, the impedance of the exciter becomes larger and the current becomes slightly smaller. Conversely, the current becomes slightly larger.

[0064] When the input voltage is, the base current is the DC component I BQ With the alternating current i b According to the control of the transistor base current on the collector current, the collector will generate an AC current i c， i c =βi b , the total current is i C =I CQ +βib, Collector dynamic current i c The collector resistor R c Generate a c The alternating voltage with the same waveform is due to R c The upper voltage increases, and the tube voltage drops u CE decreases, and vice versa, it increases, that is, the tube voltage drop is in the DC component U CEQ On this basis, the c The alternating voltage u changes in the opposite direction ce , the DC component U in the tube voltage drop CEQ Remove, and we get the same value as the input voltage u i The amplified AC voltage u0 with opposite phase. Set a suitable static operating point so that the AC signal is above the DC component, ensuring that the transistor always works in the amplified state during the entire cycle of the input signal, and the output voltage waveform will not produce nonlinear distortion.

[0065] The electromagnetic vibrator consists of an electromagnet, an electromagnetic coil and an armature. When the input of the vibrator is a sine wave, the suction formula is: [8] :

[0066]

[0067] Where μ0—vacuum magnetic permeability (H / m);

[0068] A0—Electromagnet air gap cross-sectional area (m 2 );

[0069] V m —voltage amplitude (V);

[0070] N0—number of turns of electromagnet coil;

[0071] L0—electromagnet coil inductance (M);

[0072] R m —Magnetic reluctance of the electromagnet (A / Wb);

[0073] t—time (s);

[0074] f i —Excitation frequency (Hz).

[0075] From the formula, we can see that changing the vibration frequency f i and the terminal voltage V of the electromagnet m The amplitude of the excitation force can be changed.

[0076] The general simple harmonic oscillation formula can be expressed as:

[0077] X(t)=Asin(ωt+ψ)

[0078] The period of simple harmonic oscillation is:

[0079]

[0080] The acceleration of simple harmonic oscillation is:

[0081]

[0082] The magnitude of the exciter force:

[0083] F=ma

[0084] The series of detailed descriptions listed above are only specific descriptions of feasible implementation methods of the present invention. They are not intended to limit the scope of protection of the present invention. All equivalent methods or changes that do not deviate from the technical creation of the present invention should be included in the scope of protection of the present invention.

Claims

1. A manual and automatic intermittent amplitude modulation and frequency modulation electromagnetic vibration platform, characterized in that: include: A seed plate (1), a vibrator (4), a bracket (5), a base frame (6), a control device (7) capable of adjusting frequency and amplitude, and a leveling device (8); The seed tray is connected to the seed tray base frame (6) by bolts and nuts through four side fixing sheets (1b); four springs (3) of the same specification are fixedly connected to the seed tray (1) and the four corners of the bracket (5) of the vibration table; the bolts (2) inside the springs play a vertical restraining role; the vibrator (4) is located in the middle position below the seed tray; the top of its table (4a) forms a coaxial center with the hollow cylindrical block (9) under the base frame (6) and is welded together; the top rod of the vibrator (4) provides power for the reciprocating simple harmonic motion of the vibrating seed tray; the leveling device (8) is installed at the bottom end of the bracket and fixed by bolts and nuts; the small round hole (5b) on the bottom end of the bracket cooperates with the spirit level on the control device to compensate for the defect of the vibration table being uneven due to uneven ground as the leveling device (8) moves; The control device (7) comprises a signal generator plate, a power amplifier plate, a vibration sensor on the vibration table, and a photoelectric switch a and a photoelectric switch b on the assembly line and the vibration table bracket, which can manually or automatically control the frequency and amplitude of the vibration plate vibration, adjust the output power of the power amplifier, and realize the vibration of the vibration table. The photoelectric switches a, b, and the vibration sensor are connected to the single-chip microcomputer interface. The single-chip microcomputer, the power amplifier plate, and the exciter, which act as a signal generator, are connected in series through wires to provide a voltage signal to the exciter. When automatically controlled, the single-chip microcomputer generates a voltage signal with a corresponding frequency and amplitude for the high and low level signals received from the photoelectric switch according to programming, and controls the exciter through amplification by the power amplifier plate to make the vibration table vibrate. The single-chip microcomputer determines whether the expected value is reached according to the amplitude and frequency values ​​of the vibration sensor. If not, the signal amplitude and frequency are automatically adjusted. When in manual mode, the left and right buttons and the up and down buttons can be used to adjust the frequency and amplitude respectively. The single-chip microcomputer generates a voltage signal with a corresponding frequency and amplitude according to programming to generate a sine signal that meets the needs, and displays the type of the generated wave, the frequency and amplitude of the wave on the liquid crystal screen at the same time.

2. The manual-automatic intermittent amplitude modulation and frequency modulation electromagnetic vibration platform according to claim 1 is characterized in that: The vibration exciter (4) can adjust the amplitude of the seed plate to 0-10mm.

3. The manual-automatic intermittent amplitude modulation and frequency modulation electromagnetic vibration platform according to claim 1 is characterized in that: The bottom surface of the seed tray (1) is provided with small holes spaced 1 cm apart, so as to provide an upward force to the seeds by adding an air flow field, thereby helping the seeds to achieve a better "boiling" effect.

4. The manual-automatic intermittent amplitude modulation and frequency modulation electromagnetic vibration platform according to claim 1 is characterized in that: Spring bolts are installed at the four corners of the bracket. The bolt in the middle of the spring plays a vertical constraint role, limiting vertical movement. The spring bolts of the same specifications at the four corners reduce the amplitude of the vibrating seed plate and play a vibration reduction role.

5. The manual-automatic intermittent amplitude modulation and frequency modulation electromagnetic vibration platform according to claim 1 is characterized in that: The leveling device (8) comprises four groups, namely, leveling device 1, leveling device 2, leveling device 3, and leveling device 4. If the controller detects that the bubble of the spirit level is not in the center, the platform is uneven, and the length of the column is increased or decreased by adjusting the corresponding leveling device until the vibration table is stable.

6. The manual-automatic intermittent amplitude modulation and frequency modulation electromagnetic vibration platform according to claim 1 is characterized in that: A triode is used to control the power amplifier, a common-emitter amplifier circuit is used to increase the voltage, a common-collector amplifier circuit is used to increase the current, and a sliding rheostat is used to control the amplified voltage and current; when in automatic mode, the sliding rheostat is at an ideal value and remains stationary. When the voltage signal from the signal generator is transmitted, the voltage and current are amplified to increase the output power to the exciter, allowing the exciter to vibrate; when the switch of the signal generator is in manual mode, when the output power of the power amplifier is insufficient, the resistance value can be changed by sliding the sliding piece of the sliding rheostat, thereby amplifying the voltage and current and changing the output power so that the exciter can achieve a good vibration effect.

7. The manual-automatic intermittent amplitude modulation and frequency modulation electromagnetic vibration platform according to claim 1 is characterized in that: A groove with a slope is arranged on the leveling device (8), so that the bolt (2) can move in the groove, so that the column is lengthened or shortened, and the vibration table is stable and does not shake.

8. A control method for a manual-automatic intermittent amplitude modulation and frequency modulation electromagnetic vibration platform, characterized in that: When the switch of the signal generator is in the automatic position, intermittent automatic amplitude modulation and frequency modulation are realized; the details are as follows: During work initialization, the single-chip microcomputer generates a low-frequency, low-amplitude sinusoidal signal with energy-saving amplitude a (mm) and frequency b (Hz). Through the power amplifier, the vibrator is vibrated in an energy-saving state. The seed suction disc is located above the seedling tray of the assembly line. The photoelectric switch a detects the obstruction of the seed suction disc, and the signal generated by the single-chip microcomputer remains unchanged. When the seed suction disc leaves the assembly line, the photoelectric switch a receives the signal that the seed suction disc has left. The photoelectric switch a gives the single-chip microcomputer a low-level signal in advance to prepare. According to the programming, the single-chip microcomputer gradually increases the voltage signal at a rate of 2hz / 1s and an amplitude of 2mm / s. The voltage and current are amplified by the power amplifier to increase the output power to the vibrator. Before the seed suction disc reaches the top of the vibration table, the amplitude A (mm) and frequency B (hz) are increased to the ideal vibration parameters. The vibration sensor gives the vibration parameters of the vibration table to the single-chip microcomputer. If the expected values ​​are not reached, the single-chip microcomputer will increase the amplitude and frequency of the signal. When the seed suction disc reaches the top of the seed tray and is ready to suck seeds, the photoelectric switch b detects that the obstruction of the seed suction disc is at a high level, and the signal generated by the single-chip microcomputer remains unchanged. , maintain the voltage signal of ideal frequency and amplitude, maintain the power output of the power amplifier, let the exciter maintain the ideal vibration parameters, let the seeds in the seed tray vibrate evenly, facilitate the adsorption of the seed suction tray, and improve the seed absorption effect of the seed suction tray; when the seed suction tray finishes absorbing seeds and leaves the vibration table, the photoelectric switch b receives the signal of the seed suction tray leaving and gives a low-level signal to the single-chip microcomputer. The single-chip microcomputer receives the low-level signal of the photoelectric switch b according to the programming. The single-chip microcomputer gradually increases the voltage signal at a rate of 2hz / 1s and an amplitude of 2mm / s according to the programming. The voltage and current are amplified by the power amplifier, and the output power is reduced to the exciter, which is reduced to the energy-saving parameters of amplitude a (mm) and frequency b (hz), so as not to affect the work of the seed suction tray and save energy, and at the same time, the service life can be extended; when the seed suction tray reaches the top of the assembly line seedling tray, the photoelectric switch a detects the obstruction of the seed suction tray and gives a high-level signal to the single-chip microcomputer. The signal generated by the single-chip microcomputer remains unchanged, and the exciter is in an ideal energy-saving state through the power amplifier, so that the service life of the vibration table is extended.

9. The control method of the manual-automatic intermittent amplitude modulation and frequency modulation electromagnetic vibration platform according to claim 8 is characterized in that: When in manual mode, adjust the frequency and amplitude of the signal generator to achieve the desired parameters, transmit the signal to the power amplifier to amplify the voltage and current, and output the ideal power to the exciter so that the vibration table can continue to vibrate ideally. If you feel that the output power needs to be increased, you can adjust the slider of the power amplifier's sliding rheostat to adjust the resistance value, change the amplified voltage and current to increase the output power. The vibration sensor sends the vibration parameters of the vibration table to the microcontroller. If the expected values ​​are not reached, the amplitude and frequency of the signal can be increased by pressing the button.

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