Work vehicle

Abstract

To solve the problem with a conventional work vehicle that the usability when using convenient functions is not always satisfactory, more specifically, in a work vehicle like a conventional rice planting machine, fertility degree measurement for automatically adjusting a fertilizer application amount, for example, cannot always be used easily.SOLUTION: A rice planting machine for planting seedlings to a farm field while travelling includes: a seedling planting device 20 for planting seedlings; and a sensor 30 for detecting electric resistance of soil between a first sensor electrode part 31 and a second sensor electrode part 32 for calculating a fertility degree of soil in the farm field. The first sensor electrode part 31 and the second sensor electrode part 32 are attached to the seedling planting device 20.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a work vehicle such as a rice transplanter.

Background Art

[0002] In a work vehicle provided with a material conveying device at the front part of a traveling vehicle body, a fertilizer applying device at the rear part of the traveling vehicle body, a first field information detecting member for detecting field information on the traveling vehicle body, and a control device for changing the fertilizer application amount of the fertilizer applying device from the field information detected by the first field information detecting member, a work vehicle having the first field information detecting member provided below the material conveying device is known (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, the inventor of the present invention considers various needs of work vehicle users and believes that the trend of continuously implementing convenient functions on work vehicles such as rice transplanters is accelerating more and more.

[0005] However, the inventor has noticed that the usability of conventional work vehicles is not always good when using convenient functions.

[0006] More specifically, the inventor has noticed that, for a work vehicle such as a conventional rice transplanter, for example, the fertility measurement for automatically adjusting the fertilizer application amount is not always easily available.

[0007] An object of the present invention is to provide a work vehicle that can improve usability in consideration of the above-described conventional problems.

Means for Solving the Problems

[0008] The first invention is a work vehicle that plants seedlings in a field while traveling, a seedling planting device for planting the seedlings, a sensor that detects the electrical resistance of the soil between a first sensor electrode part and a second sensor electrode part in order to calculate the fertility of the soil in the field, and is provided with a work vehicle characterized in that the first sensor electrode part and the second sensor electrode part are attached to the seedling planting device.

[0009] In the second invention, the seedling planting device has a float whose bottom surface of the float is brought into contact with the soil surface of the soil, and a seedling planting main body frame from which the float is suspended, and the work vehicle according to the first invention, characterized in that the first sensor electrode part and the second sensor electrode part are attached to the seedling planting main body frame.

[0010] In the third invention, the seedling planting device has a float whose bottom surface of the float is brought into contact with the soil surface of the soil, and the work vehicle according to the first invention, characterized in that the first sensor electrode part and the second sensor electrode part are attached to the bottom surface of the float.

[0011] In the fourth invention, the seedling planting device has a furrow opener for making a furrow on the soil surface, the first sensor electrode part and the second sensor electrode part are attached in front of the furrow opener, and the work vehicle according to the second invention, characterized in that the first sensor electrode part and the second sensor electrode part are higher than the bottom surface of the furrow opener of the furrow opener.

[0012] In the fifth invention, the work vehicle according to the fourth invention is characterized in that the first sensor electrode part and the second sensor electrode part are lower than the bottom surface of the float.

[0013] According to the sixth aspect of the present invention, the seedling planting device has a land leveling rotor for leveling the soil surface, and the first sensor electrode portion and the second sensor electrode portion are attached behind the land leveling rotor, which is a working vehicle according to the fifth aspect of the present invention.

[0014] According to the seventh aspect of the present invention, the positions of the first sensor electrode portion and the second sensor electrode portion are shifted inward or outward of the vehicle body with respect to the left - right direction compared to the positions of the left and right wheels, which is a working vehicle according to the sixth aspect of the present invention.

[0015] According to the eighth aspect of the present invention, the calculation of the fertility based on the detected electrical resistance is adjusted according to the seedling planting depth at which the seedlings are planted, which is a working vehicle according to the seventh aspect of the present invention.

[0016] According to the ninth aspect of the present invention, the float is suspended from the seedling planting main body frame via a float suspension member rotatably attached to the seedling planting main body frame, a seedling planting depth adjustment lever member for rotating the float suspension member is provided, a pin member is erected on the float suspension member, a pin member attitude sensor for detecting the attitude of the pin member is attached to the seedling planting main body frame, and the direction of the pin member is upward at a rotation angle of the float suspension member corresponding to a predetermined seedling planting depth, which is a working vehicle according to the eighth aspect of the present invention.

Advantages of the Invention

[0017] According to the first aspect of the present invention, it is possible to improve usability.

[0018] According to the second aspect of the present invention, in addition to the effect of the first aspect of the present invention, it is possible to further improve usability.

[0019] According to the third aspect of the present invention, in addition to the effects of the first aspect of the present invention, it is possible to further improve the usability.

[0020] According to the fourth aspect of the present invention, in addition to the effects of the second aspect of the present invention, it is possible to reduce the burden on the operator.

[0021] According to the fifth aspect of the present invention, in addition to the effects of the fourth aspect of the present invention, it is possible to improve the convenience.

[0022] According to the sixth aspect of the present invention, in addition to the effects of the fifth aspect of the present invention, it is possible to further improve the convenience.

[0023] According to the seventh aspect of the present invention, in addition to the effects of the sixth aspect of the present invention, it is possible to improve the practicality.

[0024] According to the eighth aspect of the present invention, in addition to the effects of the seventh aspect of the present invention, it is possible to improve the reliability.

[0025] According to the ninth aspect of the present invention, in addition to the effects of the eighth aspect of the present invention, it is possible to simplify the configuration.

Brief Description of the Drawings

[0026]

Figure 1

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Figure 19

Embodiments for Carrying Out the Invention

[0027] While referring to the drawings, embodiments of the present invention will be described in detail.

[0028] The same applies hereinafter. However, some components may not be shown in the drawings, or may be shown perspectively or omitted.

[0029] While explaining the operation of the rice transplanter according to the embodiment of the present invention, the operation control method of the work vehicle of the invention related to the present invention, which is realized by the rear controller 103 or the like, will also be explained.

[0030] Such a rice transplanter is a work vehicle that plants seedlings in a field while traveling, and is a specific example of the work vehicle in the present invention.

[0031] (1) First, the configuration and operation of the rice transplanter according to the embodiment of the present invention will be specifically described.

[0032] The sensor 30 is a sensor that detects the electrical resistance of the soil between the first sensor electrode part 31 and the second sensor electrode part 32 in order to calculate the fertility of the soil in the field. The first sensor electrode part 31 and the second sensor electrode part 32 are attached to the seedling planting device 20 that plants seedlings.

[0033] For example, as shown in FIG. 1(a), which is a left side view of the rice transplanter according to the embodiment of the present invention, and FIG. 1(b), which is a plan view of the rice transplanter according to the embodiment of the present invention, in the fertility measurement by the first sensor electrode part 31 and the second sensor electrode part 32 as the rice transplanter float electrodes, the attachment of the first sensor electrode part 31 and the second sensor electrode part 32 is performed at the symmetric float electrode arrangement position P.

[0034] In a rice transplanter to which a fertilizer applicator is attached, by arranging a first sensor electrode part 31 and a second sensor electrode part 32 on a float 26 of a planting part of a seedling planting device 20, it is possible to measure the fertility of soil. A configuration in which electrode arrangement is performed by providing a so-called slip ring to a wheel 10 such as a front wheel tends to be expensive, but by arranging the electrodes on the float 26, it is possible to measure the fertility of the soil in the field with a low-cost configuration.

[0035] The first sensor electrode part 31 and the second sensor electrode part 32 are symmetrically arranged with respect to the left-right direction so that the float 26, which is a central float of the planting part, is sandwiched therebetween. By measuring the electrical resistance between two points of the soil sandwiched by the first sensor electrode part 31 and the second sensor electrode part 32, the amount of electrolyte inside the soil can be estimated.

[0036] The seedling planting device 20 has a float 26 in which a float bottom surface 26f is brought into contact with the soil surface of the soil. The first sensor electrode part 31 and the second sensor electrode part 32 are attached to the float bottom surface 26f.

[0037] For example, as shown in Fig. 2(a), which is a perspective view of the vicinity of the float 26 of the rice transplanter according to the embodiment of the present invention, and Fig. 2(b), which is a bottom view of the vicinity of the float 26 of the rice transplanter according to the embodiment of the present invention, the attachment states of the first sensor electrode part 31 and the second sensor electrode part 32 are visible from the side float upper surface and the side float bottom surface of the float 26.

[0038] The first sensor electrode part 31 and the second sensor electrode part 32 are arranged at two or more locations on the float bottom surface 26f by being fastened to the float part of the float 26 with bolts or the like, and are not in electrical contact with other electrodes and metal parts 102 such as a metal frame and are insulated. By insulating the electrodes of the first sensor electrode part 31 and the second sensor electrode part 32 in this way, it is possible to accurately measure the electrical resistance between two points of the soil while eliminating unnecessary electrical resistance.

[0039] The first sensor electrode portion 31 and the second sensor electrode portion 32 are attached to the float 26 by being clamped together with the covering plate 101, and by utilizing electrical conduction with the covering plate 101, a sufficient sensor electrode contact area with the soil can be ensured.

[0040] Of course, since it is important to ensure such a sensor electrode contact area, a configuration in which the covering plate 101 overlaps the first sensor electrode portion 31 and the second sensor electrode portion 32 in plan view may be adopted, or a configuration in which the soil plate 101 does not overlap the first sensor electrode portion 31 and the second sensor electrode portion 32 in plan view may be adopted.

[0041] The electrical conductivity of the soil described above is measured and recorded from the electrical resistance between two or more electrodes such as the first sensor electrode portion 31 and the second sensor electrode portion 32. Such electrical conductivity can be calculated from the surface area of the electrodes, the internal resistance of the circuit, and the detected voltage, etc.

[0042] When a system for acquiring position information by GNSS (Global Navigation Satellite System) is implemented, when the vehicle body movement distance from the most recent point where the electrical conductivity was recorded exceeds a predetermined distance, the position information is recorded together with the electrical conductivity. Since the electrical conductivity is recorded for each predetermined distance, redundant data recording is avoided.

[0043] Even when a system for acquiring position information by GNSS is implemented, when radio wave reception failure or the like occurs and position information cannot be acquired by GNSS, every time the vehicle body movement distance measured by the rear wheel rotation sensor reaches a predetermined distance, the position information is recorded together with the electrical conductivity.

[0044] When a specification without a GNSS antenna installed and a system for acquiring position information using GNSS is not implemented, every time the vehicle body movement distance measured by the rear wheel rotation sensor reaches a predetermined distance, a mode in which position information is recorded together with the electrical conductivity can also be considered.

[0045] The measured electrical conductivity of the field is not necessarily recorded, and a mode in which the amount of fertilization is increased or decreased according to the measurement result can also be considered. The amount of fertilization can be adjusted according to the fertility.

[0046] A mode in which the amount of fertilization is increased or decreased based on criteria such as the average value and standard deviation of the electrical conductivity is performed only when the number of electrical conductivity data equal to or more than a predetermined number is acquired can also be considered.

[0047] Judgment of whether or not the grounding state of the float 26 is normal, which is performed by a so-called float elevation angle sensor or the like, which is a float angle sensor of the center float section, can be adopted as one of the electrical conductivity recording conditions of the first sensor electrode section 31 and the second sensor electrode section 32.

[0048] For example, as shown in FIG. 3, which is an explanatory diagram of the sensor 30 of the rice transplanter according to the embodiment of the present invention, in the fertilizer clogging sensor input circuit of the rear controller 103 where the sensor electrode section of the fertilizer clogging sensor section is diverted, the time delay at the voltage rise from 0 volts to 5 volts hardly occurs due to the diode 104, but the time delay for reducing noise due to the filter effect occurs due to the RC circuit 105.

[0049] In the electrode input circuits of the first sensor electrode portion 31 and the second sensor electrode portion 32, by arranging electrical elements using the diode 104 and the RC circuit 105, when a change in state from a state of high electrical conductivity to a state of low electrical conductivity is induced, a time delay is caused. Even when momentary floating of the first sensor electrode portion 31 and the second sensor electrode portion 32 occurs due to vehicle body bounce or the like in the field, it is difficult for the electrical conductivity to immediately become zero. Such an arrangement of electrical elements is realized by effectively using the empty space of the existing fertilizer clogging sensor portion.

[0050] By alternatively adopting an arrangement of electrical elements using another diode, an aspect can be considered in which such a time delay is not caused when a change in state from a state of high electrical conductivity to a state of low electrical conductivity is induced. Even when a rapid passage through a location with high fertility occurs, immediate response can be made.

[0051] (2) Next, the configuration and operation of the rice transplanter according to the embodiment of the present invention will be described more specifically.

[0052] The seedling planting device 20 has a float 26 whose float bottom surface 26f is brought into contact with the soil surface of the soil, and a seedling planting main body frame 21 from which the float 26 is suspended. The first sensor electrode portion 31 and the second sensor electrode portion 32 are attached to the seedling planting main body frame 21.

[0053] For example, as shown in FIG. 4 which is a left side view (part one) near the float 26 of the rice transplanter according to the first modification of the embodiment of the present invention, in the measurement of fertility by the first sensor electrode portion 31 and the second sensor electrode portion 32 as simple electrode sensors, when a large external force is applied, the electrode plates of the first sensor electrode portion 31 and the second sensor electrode portion 32 escape in a rotational direction toward the rear side of the vehicle body against the elastic force of the spring 201, thereby suppressing the occurrence of electrode plate breakage.

[0054] That is, the electrode plates of the first sensor electrode portion 31 and the second sensor electrode portion 32 are constituted by leaf springs, and when seedling planting is performed, the contact of the electrode plates with the soil surface is always ensured. Since the electrode plates of the first sensor electrode portion 31 and the second sensor electrode portion 32 are always in contact with the soil surface in this way, not only is accurate electrical resistance measurement leading to accurate fertility calculation performed, but also the occurrence of electrode plate breakage is suppressed by utilizing the leaf spring clearance accompanied by rotation.

[0055] Such a rotation fulcrum for rotation is provided above the electrode plates of the first sensor electrode portion 31 and the second sensor electrode portion 32. By utilizing gravity, the rotation of the electrode plates is realized by their own weight, so the contact of the electrode plates with the soil surface is ensured with a low-cost configuration.

[0056] For example, as shown in FIG. 5 which is a left side view (part two) near the float 26 of the rice transplanter of the first modification example of the embodiment in the present invention, when a large external force is applied, the electrode plates of the first sensor electrode portion 31 and the second sensor electrode portion 32 escape, but since the spring 201 functions as a return spring, the return of the electrode plates to their normal positions is performed smoothly.

[0057] That is, by utilizing a torque spring or the like, the spring 201 is inserted into the rotation fulcrums of the first sensor electrode portion 31 and the second sensor electrode portion 32. The generation of the state where the electrode plates float due to the bounce of the planting portion of the seedling planting device 20, which makes it impossible to perform electrical resistance measurement, is suppressed by the electrode plate pressing force accompanying the elastic force of the spring 201 applied toward the soil surface, so the realization of accurate fertility calculation is expected.

[0058] The leaf spring relief directions of the above-described first sensor electrode portion 31 and second sensor electrode portion 32 are directed toward the rear side of the vehicle body. When the vehicle body moves forward, electrode plate breakage caused by mechanical lock, which is likely to occur in a specification where such a leaf spring relief direction is directed toward the front side of the vehicle body, is less likely to occur. When the vehicle body moves backward, since the planting portion of the seedling planting device 20 is raised, electrode plate breakage due to leaf spring relief hardly occurs at all.

[0059] For example, as shown in FIGS. 6(a) and 6(b), which are left side views (parts three and four) near the float 26 of the rice transplanter according to the first modification of the embodiment of the present invention, since the lock plate 202 abuts against a so-called planting portion frame such as the seedling planting main body frame 21, the electrode plates of the first sensor electrode portion 31 and the second sensor electrode portion 32 do not rotate excessively in the rotational direction toward the front side of the vehicle body, and the electrode plates are surely returned to their normal positions.

[0060] That is, the lock plate 202 is attached so that the electrode plates of the first sensor electrode portion 31 and the second sensor electrode portion 32 do not rotate toward the front side of the vehicle body by a rotation amount exceeding the required rotation amount. The occurrence of electrode plate breakage caused by mechanical lock that may occur due to an excessive rotation amount in the direction toward the front side of the vehicle body is suppressed.

[0061] The seedling planting device 20 has a furrow opener 27 for forming a furrow on the soil surface. The first sensor electrode portion 31 and the second sensor electrode portion 32 are attached in front of the furrow opener 27.

[0062] For example, as shown in FIG. 7, which is a left side view (part five) near the float 26 of the rice transplanter according to the first modification of the embodiment of the present invention, the electrode plates of the first sensor electrode portion 31 and the second sensor electrode portion 32 are arranged in front of the furrow opener 27.

[0063] That is, in a rice transplanter configured to dispose a first sensor electrode portion 31 and a second sensor electrode portion 32 as variable fertilization type electrode sensors in a planting portion of a seedling planting device 20, the first sensor electrode portion 31 and the second sensor electrode portion 32 are disposed on the front side of the vehicle body compared to the furrow opener 27. In a configuration where the first sensor electrode portion 31 and the second sensor electrode portion 32 are disposed on the rear side of the vehicle body compared to the furrow opener 27, the electrical resistance for providing fertility may change due to the influence of fertilizer to which the electrical resistance is applied, but in a configuration where the first sensor electrode portion 31 and the second sensor electrode portion 32 are thus disposed on the front side of the vehicle body, it is difficult to change due to the influence of fertilizer to which the electrical resistance is applied.

[0064] The first sensor electrode portion 31 and the second sensor electrode portion 32 are higher than the bottom surface 27f of the furrow opener 27 of the furrow opener 27.

[0065] For example, as shown in FIG. 8 which is a left side view (part six) near the float 26 of the rice transplanter according to the first modification of the embodiment of the present invention, the electrodes of the first sensor electrode portion 31 and the second sensor electrode portion 32 are arranged at a position higher than the position of the bottom surface 27f of the furrow opener 27.

[0066] That is, the electrode plates of the first sensor electrode portion 31 and the second sensor electrode portion 32 are higher than the bottom surface 27f of the furrow opener 27. Even when the planting portion of the seedling planting device 20 is lowered, almost no electrode plate breakage that is likely to occur in a specification where the electrode plate is lower than the furrow opener 27 occurs.

[0067] The first sensor electrode portion 31 and the second sensor electrode portion 32 are lower than the bottom surface 26f of the float 26.

[0068] For example, as shown in FIG. 9 which is a left side view (part seven) near the float 26 of the rice transplanter according to the first modification of the embodiment of the present invention, the electrodes of the first sensor electrode portion 31 and the second sensor electrode portion 32 are arranged at a position lower than the position of the bottom surface 26f of the float 26.

[0069] That is, the electrode plates of the first sensor electrode part 31 and the second sensor electrode part 32 are lower than the float bottom surface 26f. Even when the water volume is small or the soil is hard, the electrode plate floating state that is likely to occur in the specification where the electrode plate is higher than the float 26 hardly occurs at all, and accurate electrical resistance measurement is promoted.

[0070] The seedling planting device 20 has a leveling rotor 28 for leveling the soil surface. The first sensor electrode part 31 and the second sensor electrode part 32 are attached behind the leveling rotor 28.

[0071] For example, as shown in FIG. 10 which is a left side view (Part VIII) near the float 26 of the rice transplanter of the first modification of the embodiment in the present invention, the positions of the electrode plates of the first sensor electrode part 31 and the second sensor electrode part 32 are arranged behind the leveling position by the leveling rotor 28.

[0072] That is, the positions of the electrode plates of the first sensor electrode part 31 and the second sensor electrode part 32 are behind the position of the soil surface leveled by the leveling rotor 28. Since the unevenness of the soil surface is almost eliminated by the leveling by the leveling rotor 28, the electrode plate height is stably maintained.

[0073] The positions of the first sensor electrode part 31 and the second sensor electrode part 32 are shifted inward or outward of the vehicle body with respect to the left - right direction compared to the positions of the left and right wheels 10.

[0074] For example, as shown in FIG. 11 which is a plan view (Part I) near the float 26 of the rice transplanter of the first modification of the embodiment in the present invention, the positions of the electrode plates of the first sensor electrode part 31 and the second sensor electrode part 32 are symmetric positions with respect to the left - right direction that do not depend on the number of seedling planting rows and are arranged so as not to overlap the wheel tracks of the wheels 10.

[0075] That is, the electrode plates of the first sensor electrode part 31 and the second sensor electrode part 32 are arranged at positions that do not overlap with the wheel tracks of the left and right wheels 10 and do not depend on the number of seedling planting rows. Since the variation in the measured value of the electrical resistance caused by the mud lift that is likely to occur due to the rotation of the wheels 10 is suppressed, accurate electrical resistance measurement is promoted.

[0076] The calculation of the fertility based on the detected electrical resistance is adjusted according to the seedling planting depth at which the seedlings are planted.

[0077] For example, as shown in FIGS. 12, 13, and 14, which are explanatory diagrams (Parts 1 to 3) of the fertility calculation adjustment of the rice transplanter according to the first modification of the embodiment of the present invention, when the depth of the electrode plate corresponding to the soil cultivation depth changes, inappropriate results in which the fertility expressed by SFV (Soil Fertility Value) changes are often obtained. Therefore, even when the depth of the electrode plate changes, if the concentration of the fertilizer is the same, the correction coefficient is adjusted so that an appropriate result in which the fertility is constant can be obtained.

[0078] That is, the correction value of the electrical resistance for providing fertility is changed according to the setting from the seedling planting depth adjustment lever member 23 for corresponding to various seedling planting depths. When the seedling planting depth is adjusted to increase, the electrode plate depths of the first sensor electrode part 31 and the second sensor electrode part 32 attached to the planting part of the seedling planting device 20 increase, and the fertility is likely to be overestimated, so the correction coefficient is adjusted to decrease. When the seedling planting depth is adjusted to decrease, the electrode plate depths of the first sensor electrode part 31 and the second sensor electrode part 32 attached to the planting part of the seedling planting device 20 decrease, and the fertility is likely to be underestimated, so the correction coefficient is adjusted to increase. When the seedling planting depth is changed, the electrode plate areas of the first sensor electrode part 31 and the second sensor electrode part 32 piercing the soil change. Although soil components such as the fertilizer concentration in the field hardly change without being affected by the depth, the electrical resistance for providing fertility is likely to change inappropriately due to the influence of the seedling planting depth. However, by adjusting such a correction coefficient, even if the seedling planting depth is adjusted, the electrical resistance reflecting uniform fertility can be appropriately measured.

[0079] The correction value of the electrical resistance for providing fertility is changed according to the setting from the float sensitivity adjustment dial to cope with various soil hardnesses. When the soil is hard, the electrode plate depth of the first sensor electrode part 31 and the second sensor electrode part 32 attached to the planting part of the seedling planting device 20 increases as the seedling planting depth is adjusted to increase. Since the fertility is likely to be overestimated, the correction coefficient is adjusted to decrease. When the soil is soft, the electrode plate depth of the first sensor electrode part 31 and the second sensor electrode part 32 attached to the planting part of the seedling planting device 20 decreases as the seedling planting depth is adjusted to decrease. Since the fertility is likely to be underestimated, the correction coefficient is adjusted to increase. When the seedling planting depth is changed according to the setting from the float sensitivity adjustment dial, the electrode plate area of the first sensor electrode part 31 and the second sensor electrode part 32 piercing into the soil changes. Although soil components such as the fertilizer concentration in the field hardly change without being affected by the depth, the electrical resistance for providing fertility is affected by the seedling planting depth and is likely to change inappropriately. However, by adjusting such a correction coefficient, even if the seedling planting depth is adjusted according to the setting from the float sensitivity adjustment dial, the electrical resistance reflecting uniform fertility can be appropriately measured.

[0080] The arrangement positions of the first sensor electrode part 31 and the second sensor electrode part 32, which are two electrode sensors, are symmetric positions based on the left-right direction. Such symmetry suppresses the generation of the difference in the left and right electrical resistances for providing fertility, so the realization of accurate data measurement is expected.

[0081] The horizontal positions of the first sensor electrode part 31 and the second sensor electrode part 32 based on the left-right direction are set to the same width regardless of the number of seedling planting rows. Changing the mounting width of the first sensor electrode part 31 and the second sensor electrode part 32 changes the electrical resistance. Therefore, changing the mounting width depending on the number of seedling planting rows requires changing the control correction value. However, by adopting such a setting with the same width, the fertility can be controlled with the same correction value regardless of the number of seedling planting rows.

[0082] When an operation such as pressing a button is performed to start the fertility calculation using the above-described electrical resistance measurement along with the variable fertilization operation, and even though the float 26 is grounded, if the electrical resistance value or the fertility value is an abnormal value, an error display is output on a monitor or the like. Even when the user fails to check whether normal electrical resistance measurement is being performed, the occurrence of an abnormality can be notified.

[0083] When so-called rice transplanter robot traveling is being performed, if such an error display is output, the vehicle body traveling is automatically stopped by returning the state of the HST trunion opening degree of the main transmission to the neutral state. Since the vehicle body stops, the user can surely recognize the occurrence of an error.

[0084] The float 26 is suspended from the seedling planting main body frame 21 via a float suspension member 22 rotatably attached to the seedling planting main body frame 21. A seedling planting depth adjustment lever member 23 for rotating the float suspension member 22 is provided. A pin member 24 is erected on the float suspension member 22. A pin member attitude sensor 25 for detecting the attitude of the pin member 24 is attached to the seedling planting main body frame 21.

[0085] For example, as shown in FIG. 15 which is a left side view (No. 9) near the float 26 of the rice transplanter according to the first modification of the embodiment in the present invention, a pin member 24 for detecting the seedling planting depth by the pin member attitude sensor 25 protrudes from the float suspension member 22, which may also be called a seedling planting depth frame.

[0086] That is, the pin member attitude sensor 25 is provided near the seedling planting depth adjustment lever member 23, and the seedling planting depth is measured. The set seedling planting depth can be accurately measured.

[0087] The pin member attitude sensor 25 is provided on a round pipe member or the like at the rotation fulcrum portion of the float suspension member 22, and the seedling planting depth is measured. By attaching the sensor to such a rotation fulcrum portion, the measurement error of the seedling planting depth is suppressed.

[0088] For example, as shown in FIG. 16 which is a plan view (part two) near the float 26 of the rice transplanter according to the first modification of the embodiment of the present invention, the pin member attitude sensor 25, which may also be called a seedling planting depth sensor, is arranged near the center of the vehicle body.

[0089] That is, the pin member attitude sensor 25 is arranged near the center of the vehicle body with the left - right direction as a reference. Since the detection of the unevenness of the field by the float 26 accompanied by the float sensitivity adjustment is performed near the center of the vehicle body, by avoiding arranging the sensor at the left and right ends of the vehicle body where the measurement error of the seedling planting depth is likely to be caused, mechanical errors are suppressed.

[0090] The direction of the pin member 24 is upward at the rotation angle of the float suspension member 22 corresponding to a predetermined seedling planting depth.

[0091] For example, as shown in FIG. 17 which is a left side view (part ten) near the float 26 of the rice transplanter according to the first modification of the embodiment of the present invention, the direction of the pin member 24, which may also be called a seedling planting depth lever detection pin, is upward.

[0092] That is, when the lever position of the seedling planting depth adjustment lever member 23 is at the position of the predetermined seedling planting depth as the standard position, the direction of the pin member 24 is upward. Since the pin member attitude sensor 25 is arranged upward, almost no trouble caused by mud splashing adhesion, which is likely to occur in the specification where the direction of the pin member 24 is downward, occurs, and a reduction in the influence of mud is expected.

[0093] (3) Next, with reference mainly to FIGS. 18 and 19, the configuration and operation of the rice transplanter according to the embodiment of the present invention will be described in more detail.

[0094] Here, FIG. 18 is an explanatory view of the fertilizer hopper device 301 of the rice transplanter according to the second modification of the embodiment of the present invention, and FIG. 19 is an explanatory view of the fertilizer blower device 302 of the rice transplanter according to the second modification of the embodiment of the present invention.

[0095] (3a) First, with reference mainly to FIG. 18, the fertilizer hopper device 301 of the rice transplanter according to the embodiment of the present invention will be described.

[0096] In the fertilizer hopper lid fixing mechanism of the fertilizer hopper device 301, the hook portion for fixing the fertilizer hopper lid is composed of a wire rod processed into a U shape. Both ends of the hook are inserted into the pipe, and the insertion portion brought to the central portion is removable. Even if the hook portion is damaged, due to the plug-in type specification, the hook portion can be easily replaced.

[0097] A configuration is adopted in which the hook portion taken out from the lower fertilizer hopper body presses the fertilizer hopper lid. By utilizing the diagonal cut of the round pipe at the rotation fulcrum portion, the hook portion is configured. It is not necessary to provide members for fixing the fertilizer hopper lid to both the fertilizer hopper lid and the fertilizer hopper body. It is sufficient to provide the hook portion only on the side of the fertilizer hopper body without providing a fixing member on the side of the fertilizer hopper lid, so the configuration is simple. Since so-called fulcrum crossing in the round pipe portion is utilized, even when the position of the hook portion is the release position, the hook portion is firmly fixed so as not to move.

[0098] (3b) Next, with reference mainly to FIG. 19, the fertilizer blower device 302 of the rice transplanter according to the embodiment of the present invention will be described.

[0099] In the fertilizer blower of the fertilizer blower device 302, the power on / off of the fertilizer blower is interlocked with the fertilizer clutch of the rice transplanter. A sensor for detecting such power on / off is provided in the fertilizer clutch section. When the fertilizer clutch is on, the fertilizer blower is also turned on, and when the fertilizer clutch is off, the fertilizer blower is also turned off. By interlocking with the fertilizer clutch, when the fertilizer clutch is turned off and fertilization work is not performed, the fertilizer blower is turned off without continuing to rotate, so that wear of the blower brush is suppressed, the durability of the fertilizer blower is improved, and improvement of battery life is also expected.

[0100] (3c) Next, the variable fertilization control mechanism of the rice transplanter according to the embodiment of the present invention will be described.

[0101] Regarding the map data-linked zone, it is possible to select a zone where real-time variable fertilization is performed. By designating a zone where real-time variable fertilization is performed, it is possible to perform weight reduction in a zone determined to be over-spraying fertilizer by user instruction, so that the occurrence of rice lodging and the like can be suppressed.

[0102] Regarding the map data-linked zone, real-time variable fertilization can be performed only in zones where the fertilization amount is more than the standard fertilization amount. Since excessive weight reduction in zones with a small fertilization amount can be suppressed, a decrease in the harvest amount is less likely to occur.

[0103] Regarding the map data-linked zone, real-time variable fertilization can be performed only in zones where the fertilization amount is less than the standard fertilization amount. By further reducing the fertilizer in zones where the soil fertility is sufficient, rice lodging and the like can be more reliably suppressed, and reduction of fertilizer is expected.

[0104] Regarding each of the map data-linked zones, it is possible to change the weight reduction rate of real-time variable fertilization. Since more detailed fertilization work is performed, uniform growth of rice is expected.

[0105] Note that the program of the invention related to the present invention is a program for causing a computer to execute the operations of all or some of the steps (or processes, operations, and actions, etc.) of the work vehicle operation control method of the invention related to the present invention described above, and is a program that operates in cooperation with a computer.

[0106] Also, the recording medium of the invention related to the present invention is a recording medium that records a program for causing a computer to execute all or some of the operations of all or some of the steps (or processes, operations, and actions, etc.) of the work vehicle operation control method of the invention related to the present invention described above, and is a computer-readable recording medium in which the read program is used in cooperation with a computer.

[0107] Note that the above-mentioned "some of the steps (or processes, operations, and actions, etc.)" means one or several of those multiple steps.

[0108] Also, the above-mentioned "operation of the steps (or processes, operations, and actions, etc.)" means all or some of the operations of the above-mentioned steps.

[0109] Also, one usage form of the program of the invention related to the present invention may be a form in which it is transmitted through a transmission medium such as the Internet, light, radio waves, or sound waves, read by a computer, and operates in cooperation with the computer.

[0110] Also, as the recording medium, ROM (Read Only Memory), etc. are included.

[0111] Also, the computer is not limited to pure hardware such as a CPU (Central Processing Unit), and may include firmware, an OS (Operating System), and further peripheral devices.

[0112] As described above, the configuration of the present invention may be implemented either software-wise or hardware-wise.

Industrial Applicability

[0113] The work vehicle according to the present invention can improve usability and is useful for the purpose of being used in work vehicles such as rice transplanters.

Explanation of Signs

[0114] 10 Wheels 20 Seedling planting device 21 Seedling planting main body frame 22 Float suspension member 23 Seedling planting depth adjustment lever member 24 Pin member 25 Pin member attitude sensor 26 Float 26f Float bottom surface 27 Furrow opener 27f Furrow opener bottom surface 28 Land leveling rotor 30 Sensor 31 First sensor electrode part 32 Second sensor electrode part 101 Covering plate 102 Metal part 103 Rear controller 104 Diode 105 RC circuit 201 Spring 202 Lock plate 301 Fertilizer hopper device 302 Fertilizer blower device P Float electrode arrangement position

Claims

1. A work vehicle for planting seedlings in a field while traveling, comprising: a seedling planting device for planting the seedlings; a sensor for detecting the electrical resistance of the soil between a first sensor electrode part and a second sensor electrode part in order to calculate the fertility of the soil in the field; and is provided with: The work vehicle is characterized in that the first sensor electrode part and the second sensor electrode part are attached to the seedling planting device.

2. The seedling planting device has a float whose bottom surface of the float is brought into contact with the soil surface of the soil, and a seedling planting main body frame from which the float is suspended, The work vehicle according to claim 1, wherein the first sensor electrode part and the second sensor electrode part are attached to the seedling planting main body frame.

3. The seedling planting device has a float whose bottom surface of the float is brought into contact with the soil surface of the soil, The work vehicle according to claim 1, wherein the first sensor electrode part and the second sensor electrode part are attached to the bottom surface of the float.

4. The seedling planting device has a furrow opener for forming a furrow on the soil surface, The first sensor electrode part and the second sensor electrode part are attached in front of the furrow opener, The work vehicle according to claim 2, wherein the first sensor electrode part and the second sensor electrode part are higher than the bottom surface of the furrow opener of the furrow opener.

5. The work vehicle according to claim 4, wherein the first sensor electrode part and the second sensor electrode part are lower than the bottom surface of the float.

6. The seedling planting device has a leveling rotor for leveling the soil surface, The work vehicle according to claim 5, wherein the first sensor electrode part and the second sensor electrode part are attached behind the leveling rotor.

7. The work vehicle according to claim 6, wherein the positions of the first sensor electrode part and the second sensor electrode part are shifted inward or outward of the vehicle body with respect to the left-right direction compared to the positions of the left and right wheels.

8. The work vehicle according to claim 7, wherein the calculation of the fertility based on the detected electrical resistance is adjusted according to the seedling planting depth at which the seedlings are planted.

9. The float is suspended from the seedling planting body frame via a float suspension member rotatably attached to the seedling planting body frame. A seedling planting depth adjustment lever member for rotating the float suspension member is provided. A pin member is erected on the float suspension member. A pin member attitude sensor for detecting the attitude of the pin member is attached to the seedling planting body frame. The work vehicle according to claim 8, characterized in that the direction of the pin member is upward at a rotation angle of the float suspension member corresponding to a predetermined seedling planting depth.

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