JPS6312655Y2 - - Google Patents

Description

[Detailed explanation of the idea]

The present invention relates to a transplanter, and more specifically, it simplifies the electronic circuit for driving the solenoid valves provided for switching the oil passages of the hydraulic circuit for the steering system and the hydraulic circuit for the lifting system of the planting section. We proposed a transplanter equipped with an automatic steering device that can provide a rational supply of pressure oil. The present invention will be described in detail below with reference to drawings showing embodiments thereof. Fig. 1 is a left side view of a rice transplanter equipped with an automatic steering device according to the present invention. This is done by cutting off the pressure oil supply to one of the hydraulic motors attached to each of the front wheels, and the pressure oil supply can be stopped manually by rotating the steering wheel 101 or by using a solenoid valve. This can be done automatically by energizing solenoids 2l and 2r (see Figure 4). The planting section 103 is connected to the front of the fuselage body by one top link 104 and a pair of left and right lower links 105 (only the left one is shown in the figure).
Further, the lift arm 106 (only the left one is shown in the figure) connected to the left and right lower links 105 is moved up and down by vertical movement. Four sets of seedling sensors are attached to the left and right lower links 105, respectively. That is, lower link 1 is connected to the left seedling sensor as shown in FIG.
A sensor box 108 is attached to the tip of an arm 107 made of a pipe that extends outward from the fuselage. It is set up. The touch rods 81 to 84 are made of thin conductors, the front and rear ends thereof are curved upward, the straight part in the middle is approximately 150 mm, and the front end is fixed within the sensor box 108, and the inner end thereof is curved upward. connected to electronic circuits. The touch rods 81 to 84 are spaced approximately 50 mm apart in the left and right directions of the aircraft.
3 and 84 are arranged side by side from left to right in this order, and in order to ensure this separation dimension, horizontal rods 1 made of electrical insulators are provided at the front curved part of the straight part and the rear end part.
09, 109 in an appropriate manner, and is constructed in the shape of a sled as a whole. and four tentacles81
The touch rod group consisting of ~84 is in a state where the planting part 103 is lowered and its float 110 is landing on the water,
The length of the arm 107 and the length of the touch rod itself are determined so that it can come into contact with the upper part of the seedling that constitutes the row of planted seedlings closest to the aircraft among the group of planted seedlings. FIG. 3 is a steering control circuit diagram of the transplanter of the present invention. Seedling sensor 81l shown in detail in this figure
To explain its structure, the touch rod 81 is connected to the - input terminal of the comparator 11 via a protective resistor 15, and a bias resistor 14 and two anti-parallel resistors are connected between the + and - input terminals of the comparator. Two protective diodes 16, 16 are connected in parallel. The bias resistor 14 has a high resistance value of about 10MΩ,
The potential of the - input terminal of the comparator 11 is biased to be slightly higher than the potential of the + input terminal. Now, the surface resistance value of the planted seedling Z from the base to the tip that comes into contact with the touch rod 81 is in the range of approximately 50MΩ to 100MΩ, although it depends on its moisture absorption state or moisture adhesion state, and the value is generally around 80MΩ. It is becoming. The plant base of the already planted seedling Z is in water in the field, and its potential is the same as the body ground, so when its tip comes into contact with the contact rod 81, the contact rod is grounded through the high resistance of the already planted seedling Z. Therefore, the potential of the - input terminal of the comparator 11 is slightly lower than the potential of the + input terminal, and the output terminal OUT of the comparator 11 is connected to the planted seedling Z.
will change from a low level in the case of non-contact to a high level. In this way, one seedling sensor consists of one touch rod and an electronic circuit such as a comparator 11 and a bias resistor 14 connected to it. The group of touch rods provided in
The seedling sensors related to Nos. 1, 82, 83, and 84 are represented as 81l, 82l, 83l, and 84l, respectively. On the other hand, the structure of the right hand group 8r is the same as the one on the left, with the contact rods 81, 82, 83, 81, 82, 83,
They are arranged in the order of 84. And the right handle 8
The seedling sensors related to Nos. 1, 82, 83, and 84 are respectively represented as 81r, 82r, 83r, and 84r, and the outputs of these eight left and right seedling sensors, that is, the output terminals OUT of the respective comparators 11 are obtained from the output terminals OUT of the respective comparators 11. The signals to be received are 81l and 81r, 82l and 82r, 83l
and 83r, and 84l and 84r, respectively, are input into pairs as a pair to the input ports _P10 to _P13 of the data processing device 1, which is the control center of the transplantation machine of the present invention. The sensor unit 80l consisting of seedling sensors 81l to 84l and the sensor unit 80r consisting of seedling sensors 81r to 84r are respectively attached to the left and right lower links 105 as described above, but the data processing device 1 is attached to the machine body. It is stored in a suitable place in the main body, for example, in the operation column 111. The seedling sensor is highly sensitive and detects the presence of high-resistance planted seedlings when they come into contact with the touch rod, so the end of the touch rod on the sensor box side has a structure with a covering and a grounding external conductor, like a shielded wire. and comparator 1
1. It is best to use shielded wires for the conductors used to connect to the bias resistor 14, etc., to prevent malfunctions due to external interference, and for the same purpose, shorten the distance between the touch rod and the comparator 11. However, since the output impedance of the comparator 11 is low, the wiring from the comparator 11 to the data processing device 1 (two for power supply per sensor unit, one for output per seedling sensor) is There is no need for shielding or the like for the wiring, and even if it is long, there is no need for any support. A pipe-shaped arm 107 is used for this wiring. The mounting position of the sensor unit is not limited to the above-mentioned lower link, but may be mounted on the side of the bumper 103' of the planting section 103 in front of the lower link so that information for steering can be obtained more quickly. The data processing device 1 is a so-called microcomputer, and in this embodiment, a one-chip microcomputer 8748-8 manufactured by Intel Corporation in the United States, which is also equipped with a memory device, is used. The data processing device 1 is programmed to recognize the relative positional relationship between the planted seedlings and the machine body in the following manner. That is, depending on the planting process, the planted seedlings Z will come into contact with the contact rod group 8l or 8r of either the left or right sensor unit 80l or 80r, but in either case, only the leftmost contact rod 81 will come into contact with the seedlings Z. If the seedling comes into contact with the robot (that is, if only the output of the comparator 11 connected to the touch rod 81 is reversed and this is detected by the data processing device 1), it is recognized that the aircraft is largely biased to the right. . In other words, if the row of already planted seedlings is to the left (or right) of the aircraft, it is recognized that the aircraft is too far away from (or too close to) the row of already planted seedlings. Next, when the touch rods 81 and 82 come into contact with planted seedlings, it is recognized that the aircraft is slightly biased to the right. Further, if the touch rods 82 and 83 are in contact with the planted seedlings, the machine maintains a desired distance from the row of planted seedlings and recognizes that the machine's position is normal. Furthermore, if a planted seedling comes into contact with the touch rods 83 and 84, the aircraft will be slightly biased to the left, and if a planted seedling comes into contact only with the touch lever 84, the aircraft will be greatly biased to the left. Recognize that there is. Then, depending on each situation, the steering angle required to make the vehicle travel along the rows of already planted seedlings is determined as shown in Table 1.

[Table] However, the positive and negative signs of the steering angle are positive to indicate steering to the left and negative to indicate steering to the right, and θ ₂ >
Let θ be ₁ . In addition, in order to prevent hunting in the control system and deterioration of riding comfort due to unnecessary steering, contact conditions between the seedling and the touch rod that do not apply to each of the cases 1 to 5 in Table 1. If this occurs, the steering angle is determined to be smaller (if there are four levers as in the embodiment, the steering angle is 0). For example, if only the touch rod 82 or 83 is touched, 3 of 0, 81, 82, 83 or 82, 83, 84
If it comes into contact with a book, it is set to 0. In this way, seedling sensors 81l to 84l or 81r
When the steering angle is determined based on the combination of the outputs of ~84r, that is, the output pattern, the data processing device 1 issues steering control signals from the output ports P ₁₄ and P ₁₅ to realize this steering angle. The electronic circuit connected to these output ports P ₁₄ and P ₁₅ is the solenoid valve 2 in the hydraulic circuit for steering drive shown in Fig. 4.
This is a drive circuit for controlling energization of the solenoids 2ls, 2rs, and 2cs of the solenoids 2ls, 2rs, and 2c, respectively, and includes comparators 21l, 21r, and two PNP transistors 22 connected to each other in Darlington.
1, 23l, 22r, 23r, etc. Output port P ₁₄ (or P ₁₅ ) is at a high level when the determined steering angle is 0, and when the steering angle is +θ ₂ ,
+θ ₁ (or −θ ₂ , −θ ₁ ), it becomes low level. The steering control signal issued from this output port P ₁₄ (or P ₁₅ ) is sent to the comparator 21l (or 21r).
The output terminal outputs a signal corresponding to the high/low level of the output port. This signal is input to the base of one of the Darlington-connected transistors 22l (or 22r). While the signal is at a high level, the transistor 22l (or 22r) is off, but when it changes to a low level, it is turned on, and as a result, the other transistor 23l (or 23r) is turned off.
will also turn on. In this way, the emitter of the transistor 23l (or 23r), which is turned on when the output port P ₁₄ (or P ₁₅ ) becomes low level, is at a positive potential +Vcc, and the collector is grounded to the body via the solenoid 2ls (or 2rs). ing. On the other hand, one end of the solenoid 2cs is grounded to the body, and the other end is connected to the cathodes of diodes 24 and 25 and the anode of a diode 26. The anodes of the diodes 24 and 25 are connected to the collectors of the transistors 23l and 23r, respectively, and
The cathode of diode 26 is connected to the +Vcc line. Furthermore, the cathode of another diode 27 is connected to the +Vcc line, and the anode is connected to the collector of the transistor 23l. Therefore, when the transistor 23l (or 23r) is turned on, the solenoids 2ls, 2cs (or 2rs,
2cs) will be energized. Next, the hydraulic circuit shown in FIG. 4 will be explained. 30
is a variable displacement hydraulic pump, and has a solenoid valve 2c.
and the left and right front wheels 3 through 2l and 2r, respectively.
Hydraulic motor 31l mounted directly on each of 2l and 32r
and 31r, and to the hydraulic motors 31'l and 31'r directly mounted on the left and right rear wheels 32'l and 32'r via the solenoid valve 2c to rotate them. Therefore, left front and rear wheels 32l, 32'
A hydraulic pump 3 is configured to drive the right front and rear wheels 32r and 32'r, and communicates the oil flow direction and pressure oil supply amount to a speed change lever 112 (see FIG. 1).
Adjustments are made using the movable swash plate 0, which allows selection of forward and backward movement and adjustment of travel speed. The solenoid valve 2c is a 3-port, 2-position switching type directional control valve, and when the solenoid 2cs is demagnetized, it is in the first position shown in the figure, and the solenoid valve 2d is connected to the hydraulic motor 31l side and for controlling the elevation of the planting section 103. It is designed to supply pressure oil to. On the other hand, when the solenoid 2cs is energized, it is switched to the second position to cut off the supply of pressure oil to the electromagnetic valve 2d and supply pressure oil to the hydraulic motor 31l and the like. Solenoid valve 2d has 3 ports 3
A position switching type directional control valve with solenoid 2
When demagnetizing ds ₁ and 2 ds ₂ , the pressure oil from the hydraulic pump 30 is sealed off in the illustrated position, and the oil chamber of the single-acting hydraulic cylinder 34, which is a driving member for the planting section that raises and lowers the planting section, is sealed. The planting portion 103 connected to the piston rod of the hydraulic cylinder 34 is held at the current position. On the other hand, when the solenoid 2ds ₁ is energized, the position is switched in the direction of the arrow, supplying pressure oil to the hydraulic cylinder 34, advancing the piston rod, and rotating the lift arm 106 upward to raise the planting section 103. let On the other hand, when the other solenoid _2ds2 is energized, the position is switched in the direction opposite to the arrow mark, so that the pressure oil in the oil chamber of the hydraulic cylinder 34 can be returned to the tank. As a result, the planting section 103 descends due to its own weight. On the other hand, the solenoid valve 2l (or 2r) is a two-position switching type stop valve, and when the solenoid 2ls (or 2rs) is demagnetized, the solenoid valve 2l (or 2r) is in the position shown, and the pressure oil is supplied to the hydraulic motor 31l (or 31r). and rotate it. On the other hand, solenoid 2LS
(or 2rs) is excited, the position is switched, the supply of pressure oil to the hydraulic motor 31l (or 31r) is cut off, and its rotational drive is stopped and braking is applied. Therefore, when solenoid 2ls (or 2rs) is energized, the left (or right) front wheel 3
The rotation of 2l (or 32r) will stop and the aircraft will turn to the left (or right), but as mentioned above, when solenoid 2ls (or 2rs) is energized, solenoid 2cs is also energized. Therefore, the supply of pressure oil to the hydraulic system for raising and lowering the planting section 103, that is, the solenoid valve 2d side, is cut off, so all the pressure oil is supplied to the hydraulic motor 31r, etc. (or 31l, etc.) side, and its rotation speed is controlled. As a result, the left (or right)
A strong turn will be made. Note that while such steering is performed, pressure oil is not supplied to the hydraulic cylinder 34, so if the planting section 103 is being driven upward, the upward movement is temporarily stopped, but automatic steering is not performed. During this period, the planting is in progress, and there is no need to drive the planting section 103 upward, so there is virtually no problem. In addition, 35 is a pressure relief valve, and 36 is a charge pump. Now, returning to FIG. 3 again, comparators 21l, 21
Switches 28l and 28r are interposed between the output terminals of r and the body ground, respectively. The switch 28l (or 28r) is arranged so as to close the circuit when the steering wheel 101 is rotated to the left (or right) by an appropriate amount, and the output of the comparator 21l (or 21r) is With the terminal set to low level, transistors 22l, 23l (or 22
r, 23r) is turned on, thereby energizing the solenoid 2ls (or 2rs), allowing manual steering operation. In this manner, manual operation is sufficient by simply closing the switches 28l and 28r, so there is no need to provide the steering wheel 101, and the switches 28l and 28r may be provided as push button switches on the operation column 111. Now, 41 is a steering sensor for detecting the actual steering angle of this rice transplanter. That is, the fuselage of this rice transplanter is of a folding type, and the front fuselage F relative to the rear fuselage R is rotated at the pivot joint 113 between the front fuselage F and the rear fuselage R.
In order to capture the angle of horizontal rotation, that is, the steering angle,
It is composed of a potentiometer that changes the output voltage according to the amount of horizontal rotation of the front body F. The output voltage of this steering sensor 41 is a timer IC (type 555)
The signal is input to a V/F (voltage/frequency) converter 42 consisting of a V/F converter 42, and the signal subjected to V/F conversion is input to the input port _T1 of the data processing device. This input signal allows the data processing device 1 to detect the actual steering state based on the steering control signals from the output ports P ₁₄ and P ₁₅ . Then, the data of the steering angles ±θ ₁ and ±θ ₂ determined as described above and stored in appropriate registers and the actual steering angle inputted from the steering sensor 41 via the V/F converter 42 are used. If the data of the angle of entry match, the output port P ₁₄ ,
The output of P ₁₅ is returned to high level, and the state of straight-line driving is restored. Note that the signal AUTO inputted to the data processing device 1 by an appropriately provided switch is a signal that instructs this transplanter to operate in automatic mode, and is activated by energizing the solenoid 2ds ₂ . A predetermined initial operation is performed, including the lowering of the planting section 103, and then the automatic operation as described above is performed. As detailed above, the transplanting machine according to the present invention has 1
a planting section driving member that raises and lowers the planting section using pressure oil generated by the hydraulic pump; a hydraulic motor that separately drives the left and right traveling sections; A steering solenoid valve is interposed between the hydraulic pump and supplies and disconnects pressure oil to each of the hydraulic motors; a switching solenoid valve that switches between a first position that can supply water to both sides and a second position that can supply water only to the hydraulic motor side; a seedling sensor that detects the relative positional relationship between the already planted seedlings and the machine body; a steering control circuit that controls the steering solenoid valve and the switching solenoid valve based on the sensor output, and when the seedling sensor detects a positional relationship in which the aircraft direction should be performed, the steering control circuit The steering solenoid valve is configured to supply pressure oil and the other to shut off, and the switching solenoid valve is set to the second position, so when turning the aircraft to the left (or right), the hydraulic pressure is As the pressure oil supply to the cylinder 34 is cut off, the pressure oil supply to the left (or right) hydraulic motor 31l (or 31r) is also cut off, so the pressure oil supply to the right (or left) hydraulic motors 31r, 31l is increased. ,
The advantage is that the turning force is strengthened and the steering performance is improved. In addition, in the case of the embodiment, the rear hydraulic motor 3
Pressure oil is supplied to 1'l (or 31'r), but
Due to the braking caused by the cutoff of pressure oil supply to the hydraulic motor 31l (or 31r), the oil flow resistance of the hydraulic pump on the same side increases, and the hydraulic motor 31l (or 31r)
The increase in the amount of pressure oil supplied to r) is minute.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which Fig. 1 is a left side view of the rice transplanter according to the invention, Fig. 2 is a perspective view of a group of touch rods, and Fig. 3 is a view of the rice transplanter according to the invention. FIG. 4 is a block diagram schematically showing the main parts of the electronic circuit, and FIG. 4 is a circuit diagram schematically showing the main parts of the hydraulic system. 1...Data processing device, 2l, 2r, 2c...
Solenoid valve, 2ls, 2rs, 2cs...solenoid, 22
l, 22r, 23l, 23r...transistor,
24, 25, 26, 27...diode, 34...
... Hydraulic cylinder, 103 ... Planting section.

Claims (1)

[Scope of utility model registration request] One hydraulic pump, a planting section drive member that raises and lowers the planting section using pressure oil generated by the hydraulic pump, a hydraulic motor that drives the left and right running sections separately, and each hydraulic motor. A steering solenoid valve is interposed between the hydraulic pump and supplies and disconnects pressure oil to each of the hydraulic motors; a switching solenoid valve that switches between a first position where oil can be supplied to both sides and a second position where oil can be supplied only to the hydraulic motor side; a seedling sensor that detects the relative positional relationship between the already planted seedlings and the machine body; a steering control circuit that controls the steering solenoid valve and the switching solenoid valve based on the seedling sensor output, and when the seedling sensor detects a positional relationship in which the aircraft direction should be performed, the steering control circuit A transplant machine characterized in that one steering solenoid valve is configured to supply pressure oil, the other is configured to shut off, and the switching solenoid valve is configured to be in a second position.