JPH044489Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field This invention relates to a device for controlling the height of the planting part of a rice transplanter.

(b) Conventional technology Conventionally, a planting section of a rice transplanter is used to maintain the planting section of a rice transplanter at a predetermined height from the planting surface of the field to keep the planting depth of the seedlings constant and prevent floating seedlings, etc. The height control device is
Various ideas have been devised, for example, Japanese Patent Application Laid-open No. 57-102102.
As shown in the publication, the float below the planting
The front end is vertically swingable around the rear end,
The hydraulic control valve is configured to be operated via the inner part of the Bowden wire connected to the front end of the machine, and a weight suspended from the traveling body and the outer part of the wire are interlocked and the machine travels by the operation of the weight. It is configured to perform pitching correction of the aircraft, and the one published in Japanese Patent Publication No. 57-27682 is
There was a configuration in which a horizontal sensing switch was installed in the planting section, and the output from the switch was used to correct the forward/backward tilting of the planting section via a hydraulic cylinder installed in the traveling aircraft, using the aircraft as a fulcrum. .

(c) Problems to be solved by the invention However, according to the invention disclosed in JP-A-57-102102, the relationship between the pitching of the traveling machine and the height of the planting part from the planting surface is not necessarily constant. Therefore, the height control of the planting part may not be suitable for the field conditions, and furthermore, the transmission of the operation via the Bowden wire requires considerable force because the wire has frictional resistance. Since this frictional resistance varies depending on the degree of bending of the wire, the operation sensitivity is slow and inconsistent, and furthermore, it is difficult to make the outer of the wire perform a corrective action at an angle of inclination comparable to pitching of the traveling aircraft. The rice transplanter cannot be controlled satisfactorily unless an unreasonably large weight is used, and if such a large weight is used, it will result in excessive weight of the machine and an imbalance in the weight distribution, and the rice transplanter may become unbalanced. It has the disadvantage that it impairs the overall performance, and the one published in Japanese Patent Publication No. 57-27682 is configured to correct the tilting of the planting part using the traveling body as a fulcrum, so the pitting of the traveling body does not affect the planting. There was a risk that the horizontal sensing switch would pick up the pitching and operate to correct the pitching, and the reaction force of the corrective action would induce pitching in the traveling aircraft, creating a vicious cycle.

(d) Means to solve the problem In this invention, a sensing float is installed below the planting area to slide on the planting surface of the field, and the rear part of the float is connected to the planting area. The front end of the float is pivoted on the lower surface so that its position can be adjusted and fixed freely, and the front end of the float is swingable up and down. Planting section height of a rice transplanter configured to maintain a constant height of the planting section from the planting surface by controlling expansion and contraction of a hydraulic cylinder for raising and lowering the planting section based on detection output The purpose of this invention is to provide a control device.

(e) Effect In this device, the center of ground pressure of the sensing float is located in front of the pivot point at the rear end of the sensing float, and if the planting part sinks with respect to the planting surface, the float will be in a state of forward upward slope. Conversely, when the planting section floats up, the float is tilted forward and downward. Since the forward and backward tilting of this float is detected by a horizontal sensor, only the height of the planting area from the planting surface can be measured, regardless of the pitching of the traveling body or the relative position between the traveling body and the planting area. The pitching correction of the traveling machine itself is not required, and the planting section can closely follow the planting surface and the planting depth of the seedlings can be adjusted without correction due to the depth of the hard ground in the field or the hardness or softness of the planting surface. It is to be held constant.

In addition, to adjust the planting depth of seedlings, it is only necessary to initialize the height of the planting part by changing the pivot point position of the rear end of the float up and down, and the work such as sensitivity adjustment that was required with conventional technology is eliminated. Nothing is necessary.

(f) Effects According to this invention, the horizontal sensor detects the longitudinal inclination angle of the float whose rear end is pivotally supported on the planting section to control the raising and lowering of the planting section. The attachment part can be made to follow the planting surface with high sensitivity, keeping the planting depth of seedlings constant to obtain good planting results, and eliminating the need for work such as sensitivity adjustment associated with adjusting the planting depth. This has the effect of simplifying the operation.

(G) Example The example of the present invention will be explained in detail based on the drawings.
A indicates a riding-type rice transplanter. The rice transplanter A consists of a traveling body B and a planting part C. The traveling body B has a prime mover section 2 mounted on the front part of a body frame 1, and receives power from the prime mover section 2. The power is transmitted to the transmission mechanism 4 via the belt interlocking mechanism 3, and transmitted to the rear wheels 6 disposed on the rear left and right sides of the fuselage frame 1 via the chain interlocking mechanism 5 disposed on the left and right sides of the transmission 4. Front wheels 7 arranged on the lower left and right sides of the prime mover section 2
is steered via a steering handle 9 installed upright in the driving part 8, and the planting part C connected to the rear of the traveling body B is towed, and the seedling planting work is performed while traveling in the field. It is structured as possible.

The planting section C is located below a planting section frame 11 which is connected to the rear part of the traveling body B via an elevating link 10 such as a parallel link or a trapezoidal link so as to be able to rise and fall freely.
A sensing float 12 that slides on the planting surface of the field and serves as a center float that supports part of the weight of the planting section C, and left and right floats 13 are arranged diagonally behind the same float 12 on the left and right sides, and the planting section frame 1
A seedling stand 14 is provided above the seedling stand 14 with a downward slope, and a predetermined amount of seedlings are placed at the same time from the lower edge of the seedling pine 15 placed on the upper surface of the stand 14 by rotating the planting claws 16. The material is collected at the tip of the claw 16 and planted on the planting surface of the field. It is installed vertically at the front end of the arm 18, and a planting crank 19 is connected to the middle of the arm 18.
The crank 19 is rotated by a drive mechanism built into the planting section frame 11, so that the tips of the planting claws 16 are rotated for planting.

Therefore, the planting rotation locus of the tip of the planting claw 16 is the same as that of the swing lever 17, the planting arm 18, and the planting crank 1.
9, and planting will be performed at the lowest position of the same trajectory, and since the same trajectory is constant with respect to the planting area C, the planting depth of the seedlings relative to the planting surface of the field The height will be determined by the height of the planting section C from the planting surface.

In order to maintain the optimum planting depth by keeping the height of the planting part C constant from the planting surface, the middle part of the top link 20 of the parallel link 10 that connects the traveling body B and the planting part C is A hydraulic cylinder 22 is interposed between the bracket 21 connected to the traveling body B, and the planting part C is moved up and down by the expansion and contraction of the cylinder 22. The planting area C is controlled via the controller 38 by the output from the horizontal sensor 23 disposed on the sensing float 12 which also serves as a center float.
The structure is such that it is maintained at a constant height from the planting surface.

That is, the rear part 12 of the sensing float 12
-1 A pivot point 24 protruding from the top surface and a pivot point 24
A swingable and fixable pivot arm 25 is interposed between the lower surface of the planting section frame 11 in front of the float 12, and the front end 12-2 of the float 12 is attached to the planting section frame 11. The float 12 is connected to be swingable about a pivot point 24, and a horizontal sensor 23 is disposed on the upper surface of the float 12 to detect forward and backward tilting of the float 12.
3, a substantially fan-shaped pendulum 27 made of a non-magnetic and electrically conductive material such as copper or aluminum is placed inside a case 26 fixed to the float 12, and a shaft support 28 is mounted at a substantially fan-shaped center position of the pendulum 27. Then, the same pendulum 2
The front and rear edges 29, 2 of the pendulum 27 when the sensing float 12 is horizontal and the pendulum 27 is in a freely stationary state.
9′ are the front and rear light emitting diodes 30, 3 facing each other, which are disposed in the case 26 with a distance between them.
0' and the front and rear phototransistors 31, 31', respectively, and the sensing float 1
2 tilts back and forth, and when the pendulum 27 deviates, the amount of light received by the front and rear phototransistors 31, 31' fluctuates, and the amount of light received by the phototransistors 31, 31' changes.
The output voltage fluctuates in height, and the same voltage is input to the front and rear comparators 32 of the controller 38, and when the input voltage is higher than the reference voltage Vr set to the comparator 32, it is output from the comparator 32, and the Amplifier 33, control and output relay 34, 3
4', it is configured to output to the lifting solenoids 36, 36' of an electromagnetically actuated spring center type hydraulic directional control valve 35 that controls the operation of the hydraulic cylinder 22.

The relationship between the inclination angle θ of the horizontal sensor 23 and the output voltage Vo of the front and rear phototransistors 31, 31' is as shown in FIG.
9, 29' are front and rear phototransistors 31, 3
1', the output voltage Vo increases and decreases monotonically with respect to the inclination angle θ, and the fluctuations in the output voltage Vo are converted into reference voltages by the front and rear comparators 32, respectively.
Compared to Vr, front and rear phototransistors 31, 3
Only when the output voltage Vo of 1' is higher, the output is directed to the lifting solenoids 36 and 36', respectively. Front and rear phototransistors 31, 3
1' output voltage Vo is both reference voltage
The dead zone d, which is lower than Vr and in which there is no output from both the front and rear comparators 32, is an extremely narrow range centered on the horizontal position, so this period can be regarded as the horizontal position, and the hydraulic directional control valve 35 is in a neutral state. The hydraulic cylinder 22 is maintained in a stopped state. Therefore, if the reference voltage is set low, the sensitivity of the horizontal sensor 23 becomes sharp, and if the reference voltage is set high, it becomes dull.

Note that the output voltage Vo of the front and rear comparators 32, 32' is positively fed back 46 to the reference voltage to provide hysteresis characteristics and prevent control bouncing near the reference voltage Vr.

Furthermore, the pendulum 27 is a free pendulum, and free vibration may impede inclination angle detection, but a pair of strong left and right permanent magnets 37, 37' are arranged in the case 26 with a slight gap between them. The central part of the pendulum 27 is inserted into the gap without contacting the magnets 37, 37', and the energy of the vibration of the pendulum 27 is consumed as heat by the eddy current induced in the pendulum 27, which is a good electrical conductor. Although it is a non-contact type, it obtains a damping characteristic equivalent to viscous resistance that is approximately proportional to the speed of movement, quickly absorbs vibrations, and quickly converges the pendulum 27 to a free resting position.

In this way, when the forward and backward tilting of the sensing float 12 is detected, and when the float 12 is in the forward upward tilting state, the planting section C is in a sinking state with respect to the planting surface, so the hydraulic cylinder 22 is extended and operated. When C is raised and the front is tilted downward, the planting part C is in a floating state, so the hydraulic cylinder 22 is retracted and the planting part C is automatically kept at a constant height from the planting surface. It is held in place.

Furthermore, the control relay 34 in the controller 38 is connected 44 to a lifting operation lever 39 disposed in the driving part 8 in order to raise and lower the planting part C via an automatic/manual switching relay 45. , four operating positions are set in order from the front: planting 40, lowering 41, fixed 42, and raising 43. The height of the planting section C is automatically controlled by an automatic/manual switching relay 45. It operates only when the lever 39 is between the lowering 40 and the lowering 41, and when the lever 39 passes the lowering 40 and is between the raising 43, the automatic control is canceled by the relay 45 and manual operation is performed. The lever 39 is configured to control the raising operation of the planting part C and the holding of the stopped position, and the initial setting of the planting depth of the seedlings is performed by setting the height of the planting part C by manual operation of the same lever 39. Okay, pivot arm 2
This is achieved by fixing the swinging of the pivot point 24 and adjusting the vertical position of the pivot point 24 relative to the planting section C.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram (side view) showing the main parts of the planting part height control device of the rice transplanter according to the present invention. Figure 2 shows
A schematic diagram (perspective view) showing the horizontal sensor. FIG. 3 is a graph showing the output characteristics of the horizontal sensor. Fourth
The figure is a block diagram showing the operation of the control device. Fifth
The figure is an overall side view of a rice transplanter having the proposed device. C...Planting section, 12...Sensing float,
12-1... Rear end part, 12-2... Front end part,
22...Hydraulic cylinder, 23...Horizontal sensor,
24... Pivotal point.

Claims (1)

[Scope of utility model registration request] A sensing float 12 for sliding on the planting surface of the field is arranged below the planting section C, and the rear part 12-1 of the float 12 can be adjusted and fixed in the vertical position on the bottom surface of the planting section C. The front end 12-2 is pivoted 24 to be vertically swingable, and the float 12
A horizontal sensor 23 is installed to detect the longitudinal inclination angle θ of the float 12 from the horizontal plane, and the detection output from the sensor 23 controls the expansion and contraction of the hydraulic cylinder 22 for raising and lowering the planting section C. A planting part height control device for a rice transplanter configured to maintain a constant height of the planting part C from the planting surface.