Height control system for agricultural machinery

Abstract

To provide a height control system for agricultural machinery which is easily retrofitted and has a high versatility.SOLUTION: A height control system for agricultural machinery applied to an implement 2 installed on a tractor 1 and used for an agricultural work, includes: a control part 11 provided to the tractor 1; an implement control part 21 provided to the implement 2; an antenna 31 arranged to the tractor 1; and a receiver 32 arranged to the tractor 1. The implement control part 21 acquires a height information of the tractor 1 from the receiver 32 based on the signal received by the antenna 31, calculates the height of the implement 2 with respect to the tractor 1 based on the acquired information, and transmits the signal for controlling the height of the implement 2 to the tractor control part 11 based on the calculated information. The tractor control pat 11 controls the height of the implement 2 with respect to the tractor 1 based on the received signal for controlling the height.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a height control system for agricultural work machines, and more particularly to a height control system for agricultural work machines for controlling the height of a work machine mounted on a tractor to perform agricultural work.

Background Art

[0002] A work machine mounted on a tractor to perform agricultural work can perform appropriate agricultural work by controlling its working height. For example, an auto device may be used to control the position of a soil tilling body and a tilling part in contact with the ground surface to be constant.

[0003] Further, Patent Document 1 discloses a vehicle body positioning device mounted on a traveling vehicle body for positioning the position of the traveling vehicle body, and a work machine positioning device mounted on a work machine for positioning the position of the work machine. When it is determined that the control device is traveling on the road, based on the detection value of the vehicle body positioning device and the detection value of the work machine positioning device, a technique for raising and lowering the position of the work machine with respect to the traveling vehicle body to a predetermined position is described.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, when using the above-described auto device, since the soil tilling body moves up and down along the unevenness of the ground surface, it may be difficult to keep the depth of the tilling part constant.

[0006] In Patent Document 1, it is premised on two devices, a vehicle body positioning device and a work implement positioning device, which are installed in advance, and the control of these is performed by one control device provided in a tractor (traveling vehicle body). For this reason, in order to add functions later, it is necessary to replace the entire control device of the tractor. Since the control device of the tractor also performs various controls of the tractor, adding the above functions is laborious and costly, and the configuration is not highly versatile for applying to tractors of various models.

[0007] In view of the above problems, an object of the present invention is to provide a height control system for agricultural work machines that is easy to add and has higher versatility.

Means for Solving the Problems

[0008] In order to achieve the above object, one of the height control systems for agricultural work machines of the present invention, which is applied to a work machine attached to a tractor for performing agricultural work, includes a tractor control unit provided in the tractor, a work implement control unit provided in the work implement, an antenna disposed in the tractor, and a receiver disposed in the tractor. The work implement control unit acquires information on the height of the tractor from the receiver based on a signal received by the antenna, calculates the height of the work implement with respect to the tractor based on the acquired information, and transmits a signal for controlling the height of the work implement to the tractor control unit based on the calculated information. The tractor control unit controls the height of the work implement with respect to the tractor based on the received signal for controlling the height.

Effects of the Invention

[0009] According to the present invention, in a height control system for agricultural work machines for controlling the height of a work machine attached to a tractor for performing agricultural work, addition is easy and versatility can be made higher. Problems, configurations, and effects other than the above will be clarified by the following embodiments.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0011] Embodiments for carrying out the present invention will be described.

[0012] <First Embodiment> FIG. 1 is a block diagram of the first embodiment of the height control system for agricultural working machines of the present invention.

[0013] In a configuration including a working machine 2 mounted on a tractor 1, on the tractor 1 side, a tractor control unit 11 is provided, and further, an antenna 31, an RTK-GNSS receiver 32, and a communication unit 33 are arranged. Also, on the working machine 2 side, a working machine control unit 21 is provided. The working machine 2 is a working machine for performing agricultural work. The tractor 1 may also be provided with a display unit 12 and an operation unit 13.

[0014] The tractor control unit 11 performs processes for controlling the tractor 1 and can utilize those pre - installed in the tractor 1. The tractor control unit 11 receives a signal from the implement control unit 21 and controls the lifting device of the tractor 1 based on it. Thereby, the height of the implement 2 with respect to the tractor 1 can be changed. For this reason, the tractor control unit 11 has a function of receiving a signal for changing the height of the lifting device from the outside and performing control to change the height of the lifting device based on it. The tractor control unit 11 is composed of electronic devices and the like necessary for control, processing, etc.

[0015] The tractor control unit 11 may be stored in the tractor control box 10 provided in the tractor 1. The tractor control box 10 can have a dust - proof and waterproof function, and in this case, it protects the tractor control unit 11.

[0016] The display unit 12 can be provided with means for obtaining necessary information from the tractor control unit 11 and displaying it on a display screen such as a liquid crystal, organic EL, LED, etc. For example, it is the display of height information obtained by the RTK - GNSS receiver 32, the display of received information, etc. The operation unit 13 is provided with means for operating the lifting device of the tractor 1. Thereby, the operator can manually change the height of the implement 2. For example, the height of the implement 2 can be changed while checking the display of the height information on the display unit 12.

[0017] The antenna 31 is an antenna for receiving signals from GNSS satellites. The RTK - GNSS receiver 32 is a receiver that performs RTK positioning using the signals received by the antenna 31 and the data from the reference station. The signals received here include information from GNSS satellites, and in particular, the height information at the antenna 31 (that is, the height information of the tractor 1) is included. Also, it may include position information other than the height direction.

[0018] Here, the RTK-GNSS method will be described. RTK is an abbreviation for Real Time Kinematic and is a measurement method called relative positioning. Also, GNSS is an abbreviation for Global Navigation Satellite System and indicates a satellite positioning system that receives radio waves from positioning satellites to identify positions on the ground. The RTK-GNSS method simultaneously observes two points, a reference point and an observation point, and enables accurate measurement by processing common errors. The RTK-GNSS method can acquire information in the height direction at the antenna 31. For example, data can be acquired as elevation. In addition to this, the RTK-GNSS method can acquire three-dimensional position information such as X, Y, and Z not only in the height direction.

[0019] The communication unit 33 changes the communication method or data format (e.g., a specific communication standard) of the signal applied by the RTK-GNSS receiver 32 to another communication method or data format (e.g., another specific communication standard) applied by the communication lines 102, 101. Thereby, it becomes possible to transmit information such as height received by the RTK-GNSS receiver 32 to the work machine control unit 21. Also, this information may be transmitted to the tractor control unit 11 as necessary.

[0020] The work machine control unit 21 acquires the height information of the tractor 1 from the RTK-GNSS receiver 32 via the communication unit 33. Then, based on the acquired height information of the tractor 1, the work machine control unit 21 calculates the appropriate height of the work machine 2. Then, based on the calculated height, a signal for changing the height of the work machine 2 with respect to the tractor 1 is output to the tractor control unit 11. Also, the work machine control unit 21 may control the actuator provided in the work machine 2. At this time, it is also possible to use the height information of the tractor 1 from the RTK-GNSS receiver 32.

[0021] For example, when it is desired to keep the height of the working machine 2 constant, the following control can be enabled. If it is determined from the information of the RTK-GNSS receiver 32 that the height of the tractor 1 has changed (risen or fallen), the working machine control unit 21 calculates the height of the working machine 2 that cancels out (makes zero) the height change. Then, the working machine control unit 21 outputs a signal to the tractor control unit 11 to change (lower or raise) the height of the working machine 2 with respect to the tractor 1. Based on this, the tractor control unit 11 changes the height of the working machine 2. By this, it becomes possible to perform control to keep the height of the working machine 2 constant.

[0022] The working machine control unit 21 may be stored in the working machine control box 20 provided in the working machine 2. The working machine control box 20 can have a dustproof and waterproof function, and in this case, it protects the working machine control unit 21.

[0023] The communication line 101 is a communication line that connects the tractor control unit 11 and the working machine control unit 21. The communication method of the communication line 101 can apply the standard adopted by the tractor control unit 11. For example, it is a standard such as CAN (Controller Area Network). Also, a standard using AG-PORT, which is a communication control common protocol, may be used.

[0024] One end of the communication line 102 is connected to the communication unit 33, and the other end is connected to the communication line 101 on the tractor 1 side. The same communication method as that of the communication line 101 is applied to the communication method of the communication line 102. The signal from the communication unit 33 is transmitted to the working machine control unit 21 through the communication lines 102 and 101. The signal from the working machine control unit 21 is transmitted to the tractor control unit 11 through the communication line 101.

[0025] The height control unit 301 includes an antenna 31, an RTK-GNSS receiver 32, and a communication unit 33, and can be configured as one unit, for example, an integrated device. The height control unit 301 is installed at a suitable location on the tractor 1. In this case, since it includes the antenna 31, it can be installed at a location suitable for receiving signals independently of the tractor control unit 11. Also, the height control unit 301 may be installed at a location suitable for receiving signals of the tractor 1 without including the antenna 31, with only the antenna 31. In this case, the height control unit 301 can be arranged inside the tractor 1 (for example, inside the driver's seat of the tractor 1).

[0026] FIG. 2 is a side view showing a working machine applicable to the first embodiment of the present invention. FIG. 2 shows an embodiment using a rotary working machine 50 as the working machine 2 attached to the tractor 1. Hereinafter, the traveling direction of the rotary working machine 50 is described as the forward direction. The left direction in FIG. 2 is the forward direction of the rotary working machine 50, and the vertical direction in FIG. 2 is the vertical direction of the rotary working machine 50. Also, in FIG. 2, a simplified illustration of the tractor 1 is shown.

[0027] The PTO power output from the tractor 1 is input from the input shaft 55 via a joint (not shown) and transmitted to the tilling unit 60 located below the tilling unit cover. The tilling unit 60 performs tilling work by rotating a tilling shaft having a plurality of tilling claws 62 (only one is shown in FIG. 2).

[0028] As shown in FIG. 2, the rotary working machine 50 is mounted on the rear part of the tractor 1. At this time, the mounting part 51 has a mast 51a and a lower arm 51b, and these are attached to the top link 15 and the lower link 16 on the tractor 1 side. Here, the top link 15 is arranged above the lower link 16. When the tractor control unit 11 controls the vertical movement of the lower link 16, the lower link 16 rotates around the fulcrum on the tractor 1 side, and the top link 15 also rotates around another fulcrum on the tractor 1 side. Thereby, the rotary working machine 50 can be vertically displaced. At this time, the link mechanism of the top link 15 and the lower link 16 constitutes the lifting device of the tractor 1. Note that one top link 15 is provided near the left - right center of the tractor 1, and two lower links 16 are provided on the left and right sides of the tractor 1.

[0029] The work implement control box 20 (work implement control unit 21) is installed at a suitable location of the rotary working machine 50. For example, it may be fixed to the frame 52 above the tilling unit 60.

[0030] In FIG. 2, the height control unit 301 is installed on the roof 17 provided above the driver's seat of the tractor 1. By this, the antenna 31 can be arranged at a high position and the reception sensitivity can be enhanced. Also, the antenna 31 alone may be installed on the roof 17 of the tractor 1.

[0031] For example, when it is desired to level the ground surface of a field, the following control is enabled. The antenna 31 receives signals from GNSS satellites and sends the received signals to the RTK-GNSS receiver 32. Then, information on the height of the tractor 1 is input from the RTK-GNSS receiver 32 via the communication unit 33 to the work implement control unit 21 of the rotary work implement 50 (work implement 2). At this time, the work implement control unit 21 calculates the change in its height. When the height of the tractor 1 changes, the height of the rotary work implement 50 also changes. Therefore, in order to keep the height of the rotary work implement 50 constant, the change in its height is canceled out (set to 0) to calculate the height of the rotary work implement 50. If the tractor 1 is rising, the amount of change for the rotary work implement 50 to descend is calculated, and if the tractor 1 is descending, the amount of change for the rotary work implement 50 to ascend is calculated. Then, the work implement control unit 21 outputs a signal to the tractor control unit 11 to change the height of the rotary work implement 50 with respect to the tractor 1. Based on this, the tractor control unit 11 controls the height of the lower link 16, which is the lifting device of the tractor 1. By doing this, the height of the rotary work implement 50 is controlled to be constant, so that the height of the tillage unit 60 becomes constant, and in the tillage operation, the ground surface of the field can be leveled.

[0032] As described above, in the first embodiment, since the antenna 31 of the height control unit 301 can be provided at a suitable position (for example, a high position) of the tractor 1, the reception sensitivity of signals from GNSS satellites is increased, enabling more accurate height detection. Furthermore, by performing the necessary calculations of height and processing based on the height information in the work implement control unit 21, the processing in the tractor control unit 11 is reduced, and additional installation becomes easier. The work implement 2 can be attached to various tractors, and it is possible to correspond to all tractors that are capable of inputting changes in the height of the lifting device, even those without a height detection function. Also, adding such a function is possible only by adding the height control unit 301 and changing the work implement control unit 21. Therefore, it is possible to provide a height control system for agricultural work implements that is easy to add and has higher versatility.

[0033] <Second Embodiment> FIG. 3 is a block diagram of a second embodiment of the height control system for an agricultural working machine according to the present invention. In the second embodiment, differences from the first embodiment will be mainly described, and the same reference numerals are given to the same parts, and descriptions of parts not particularly explained are omitted.

[0034] In a configuration including the working machine 2 mounted on the tractor 1, the tractor 1 side is provided with a tractor control unit 11. Further, on the working machine 2 side, a working machine control unit 21, an antenna 31', an RTK-GNSS receiver 32, and a communication unit 33 are provided. In the second embodiment, the difference from the first embodiment is that the antenna 31', the RTK-GNSS receiver 32, and the communication unit 33 are provided on the working machine 2 side.

[0035] The tractor control unit 11 and the tractor control box 10 are the same as those in the first embodiment.

[0036] The antenna 31' has the same function as the antenna 31 in the first embodiment, but in the second embodiment, it is installed on the working machine 2 side.

[0037] The communication unit 33 has the same function as in the first embodiment, but in the second embodiment, it is installed on the working machine 2 side.

[0038] The working machine control unit 21 acquires information on the height of the working machine 2 from the RTK-GNSS receiver 32 via the communication unit 33. Then, the working machine control unit 21 calculates an appropriate height of the working machine 2 based on the acquired height information of the working machine 2. And based on the calculated height, a signal for changing the height of the working machine 2 with respect to the tractor 1 is output to the tractor control unit 11. Further, the working machine control unit 21 may control the actuator provided in the working machine 2. At this time, it is also possible to use the height information of the working machine 2 from the RTK-GNSS receiver 32. The working machine control box 20 is the same as that in the first embodiment.

[0039] For example, when it is desired to keep the height of the working machine 2 constant, the following control can be enabled. If it is determined from the information of the RTK-GNSS receiver 32 that the height of the working machine 2 has changed (risen or fallen), the working machine control unit 21 calculates the height of the working machine 2 that cancels out (makes zero) the height change. Then, the working machine control unit 21 outputs a signal to change (lower or raise) the height of the working machine 2 to the tractor control unit 11. Based on this, the tractor control unit 11 changes the height of the working machine 2. By this, it becomes possible to perform control to keep the height of the working machine 2 constant.

[0040] The communication line 101 is the same as in the first embodiment.

[0041] One end of the communication line 102’ is connected to the communication unit 33, and the other end is connected to the communication line 101 on the side of the working machine 2. The communication method of the communication line 102’ is the same communication method as that of the communication line 101. The signal from the communication unit 33 is transmitted to the working machine control unit 21 through the communication lines 102’ and 101. The signal from the working machine control unit 21 is transmitted to the tractor control unit 11 through the communication line 101.

[0042] The height control unit 302 includes the RTK-GNSS receiver 32 and the communication unit 33, and can be configured as one unit, for example, as an integrated device. The height control unit 302 is installed at a suitable location of the working machine 2. On the other hand, the antenna 31’ can be installed separately from the height control unit 302 at a location suitable for receiving signals in the working machine 2, for example, at a position higher than the height control unit 302. Thereby, it also becomes easy to increase the height of the antenna 31’. Also, the height control unit 302 may be configured integrally with the antenna 31’.

[0043] FIG. 4 is a side view showing a working machine applicable to the second embodiment of the present invention. The rotary working machine 50’ shown in FIG. 4 is a configuration in which the height control unit 302 and the antenna 31’ are added to the rotary working machine 50 of FIG. 2 described in the first embodiment. Also, as shown in FIG. 2, the tractor 1 does not include the height control unit 301.

[0044] In FIG. 4, the height control unit 302 is fixed to the frame 52 using a fixing member 81. The frame 52 is a frame provided above the tilling unit 60 of the rotary working machine 50', and a frame used in the structure of the rotary working machine 50' may be applied. Further, the antenna 31' is installed at the highest position or near the highest position of the rotary working machine 50' via an arm 82 extending in the vertical direction. At this time, the antenna 31' may be arranged at the same height as the roof 17 of the tractor 1 or at a position higher than the roof 17 to enhance the reception sensitivity. The lower end of the arm 82 is fixed to the frame 52 via a fixing member 81. Also, the lower end of the frame 52 may be configured integrally with the height control unit 302. Further, the upper end of the arm 82 has the antenna 31' fixed thereto. Note that the height control unit 302 may be attached to the mast 51a.

[0045] For example, when it is desired to level the ground surface of a field, the following control is enabled. The antenna 31’ receives signals from GNSS satellites and sends the received signals to the RTK-GNSS receiver 32. Then, information on the height of the rotary working machine 50’ (working machine 2) is input from the RTK-GNSS receiver 32 to the working machine control unit 21 via the communication unit 33. At this time, the working machine control unit 21 calculates the change in its height. Then, in order to keep the height of the rotary working machine 50’ constant, it calculates the height of the rotary working machine 50’ that cancels out (makes it zero) the change in height. If the rotary working machine 50’ is rising, it calculates the amount of change to lower the rotary working machine 50’, and if the rotary working machine 50’ is descending, it calculates the amount of change to raise the rotary working machine 50’. Then, the working machine control unit 21 outputs a signal to the tractor control unit 11 to change the height of the rotary working machine 50’ with respect to the tractor 1. Based on this, the tractor control unit 11 controls the height of the lower link 16, which is the lifting device of the tractor 1. By doing this, the height of the rotary working machine 50’ is controlled to be constant, so that the height of the tilling unit 60 becomes constant, and in the tilling operation, the ground surface of the field can be leveled. Additionally, alternatively, the working machine control unit 21 may output information on the height of the rotary working machine 50’ to the tractor control unit 11, and the tractor control unit 11 may perform feedback control to control the lifting device of the tractor 1 so that the height of the rotary working machine 50’ reaches a constant target value (absolute value such as elevation).

[0046] Thus, in the second embodiment, since the antenna 31' can be provided at a suitable position (particularly a high position) of the working machine 2, the reception sensitivity of the signal from the GNSS satellite can be increased, enabling more accurate height detection. At this time, since the antenna 31' is provided on the working machine 2 side, it is possible to more accurately grasp the height of the working machine 2 compared to providing the antenna on the tractor 1. Furthermore, by performing the calculation of the height and the necessary processing based on the height information in the working machine control unit 21, the processing in the tractor control unit 11 is reduced, and additional installation becomes easier. The working machine 2 can be attached to various tractors, and it is possible to support all tractors that can input the height change of the lifting device, even those without a height detection function. Also, the addition of such a function is achieved by adding the height control unit 302 and the antenna 31' and changing the working machine control unit 21, which can be accomplished only by changing the working machine 2 side. Therefore, it is possible to provide a height control system for agricultural working machines that is easy to add and has higher versatility. Note that the antenna 31' may be arranged on the working machine 2 side and the height control unit 302 may be arranged on the tractor 1 side.

[0047] <Third Embodiment> FIG. 5 is a block diagram of a third embodiment of the height control system for an agricultural working machine of the present invention. In the third embodiment, the points different from the first and second embodiments will be mainly described, and the same reference numerals are given to the same parts, and the same description is omitted for parts not particularly described.

[0048] In a configuration including a working machine 2 attached to a tractor 1, the tractor 1 side is provided with a tractor control unit 11. Also, the working machine 2 side is provided with a working machine control unit 21, an antenna 31', an RTK - GNSS receiver 32, a communication unit 33', and a height management means control unit 35. In the third embodiment, compared to the second embodiment, a height management means control unit 35 is added to the working machine 2 side.

[0049] The tractor control unit 11 and the tractor control box 10 are the same as in the second embodiment.

[0050] The antenna 31' is the same as that of the second embodiment.

[0051] The height management means control unit 35 is a means for detecting the height of the working machine 2 provided to obtain height information by means other than obtaining it from the RTK-GNSS receiver 32. The height management means control unit 35 may be one means, or a plurality of means may be provided. Examples of the means are shown below.

[0052] The first example of the height management means control unit 35 is a configuration of a laser level. The laser level can detect a change in height by providing a light emitter outside the field and receiving the signal from the light emitter with a light receiver provided on the working machine 2. In the case of the laser level, the height management means control unit 35 provided in the working machine 2 can be applied as a light receiver or a control unit that converts it into height information based on the light receiver.

[0053] The second example of the height management means control unit 35 is a configuration for receiving a CLAS positioning signal. CLAS is an abbreviation for Centimeter Level Augmentation Service, which is a centimeter-level positioning augmentation service. It is possible to obtain height information from the CLAS positioning signal. In the case of a configuration for receiving a CLAS positioning signal, the height management means control unit 35 provided in the working machine 2 can be applied as an antenna or a receiver for receiving the CLAS positioning signal. Note that, instead of the antenna 31', an antenna for the CLAS positioning signal may be used as an antenna that includes the functions of the antenna 31'.

[0054] The third example of the height management means control unit 35 is a water surface distance detection means. In this case, it can be applied to a field with water, for example, in the case of a weeding machine. Since the water surface is basically horizontal, this is utilized. For example, by measuring the distance from a specific location of the working machine 2 to the water surface, the height of the working machine 2 relative to the water surface can be measured. As the measurement method, an appropriate means such as a non-contact type (e.g., laser, ultrasonic wave, etc.) or a contact type can be selected. In the case of the water surface distance detection means, the height management means control unit 35 provided in the working machine 2 can be applied as a measuring instrument for measuring the distance to the water surface and a control unit for converting it into height information based on that.

[0055] The fourth example of the height management means control unit 35 is a means using mapping data. In this case, the already created mapping data is used. The mapping data includes both position information and height information, and the height data of the location where the current working machine 2 is located is acquired. Therefore, when using mapping data, the height management means control unit 35 provided in the working machine 2 can be applied as a storage unit for storing the mapping data, a position acquisition means for acquiring the current position, and a calculation unit for extracting the height from the mapping data based on the current position. The position acquisition means may use the position information from the RTK-GNSS receiver 32 or another satellite positioning system. Also, the height management means control unit 35 may be provided with a processing unit for creating mapping data based on the information of the RTK-GNSS receiver 32.

[0056] The communication unit 33' transmits the signal (information) from the RTK-GNSS receiver 32 and the signal (information) from the height management means control unit 35 to the working machine control unit 21'.

[0057] The work implement control unit 21' acquires the height information of the work implement 2 from the RTK-GNSS receiver 32 and also acquires the height information from the height management means control unit 35. Then, based on the acquired height information of the work implement 2, the work implement control unit 21' calculates the appropriate height of the work implement 2. And based on the calculated height, it outputs a signal to the tractor control unit 11 to change the height of the work implement 2 with respect to the tractor 1. Also, the work implement control unit 21' may control the actuator provided in the work implement 2. At this time, it is also possible to use the height information of the work implement 2 from the RTK-GNSS receiver 32. Note that the work implement control box 20 is the same as in the first embodiment and houses the work implement control unit 21'.

[0058] For example, when it is desired to keep the height of the work implement 2 constant, the following control can be enabled. If it is determined from the information of the RTK-GNSS receiver 32 and the height management means control unit 35 that the height of the work implement 2 has changed (risen or fallen), the work implement control unit 21' calculates the height of the work implement 2 that cancels out (makes it zero) the height change. Then, the work implement control unit 21' outputs a signal to the tractor control unit 11 to change the height of the work implement 2 (fall or rise). In the tractor control unit 11, the height of the work implement 2 is changed based on this. By this, it becomes possible to perform control to keep the height of the work implement 2 constant.

[0059] In the work implement control unit 21', either one or both of the information of the RTK-GNSS receiver 32 and the height management means control unit 35 may be used. For example, when the information from the RTK-GNSS receiver 32 cannot be received, only the information from the height management means control unit 35 can be used. Also, when the information of the height management means control unit 35 cannot be received, only the information from the RTK-GNSS receiver 32 can be used. Also, a more accurate height may be calculated by using, for example, the average value, using the information of either the RTK-GNSS receiver 32 or the height management means control unit 35. Also, when correction data cannot be received from the RTK reference station, the CLAS positioning signal may be received as correction data.

[0060] The communication line 101 is the same as that in the first embodiment.

[0061] The communication line 103 is a communication line that connects the communication unit 33' and the work machine control unit 21'. The communication method of the communication line 103 can adopt a communication method applicable to the work machine control unit 21'. Note that the communication methods of the communication line 101 and the communication line 103 may be different. In this case, the work machine control unit 21' performs communication method change processing.

[0062] The height control unit 303 includes an RTK-GNSS receiver 32, a communication unit 33', and a height management means control unit 35, and can be configured as one unit, for example, an integrated device. The height control unit 303 is installed at a suitable location on the work machine 2. On the other hand, the antenna 31' can be installed at a location suitable for signal reception on the work machine 2 separately from the height control unit 303. Thereby, it also becomes easy to make the height of the antenna 31' higher than that of the height control unit 303. Also, part or all of the height management means control unit 35 may be provided separately from the height control unit 303. Further, the height control unit 303 may be integrally configured with the antenna 31'.

[0063] As a work machine applicable to the third embodiment, the rotary work machine 50' shown in FIG. 4 of the second embodiment can be used. In this case, the height control unit 303 is applied instead of the height control unit 302.

[0064] For example, when it is desired to flatten the ground surface of a field, the following control is enabled. The antenna 31' receives signals from GNSS satellites and sends the received signals to the RTK-GNSS receiver 32. Then, information on the height of the rotary working machine 50' (working machine 2) is input from the RTK-GNSS receiver 32 via the communication unit 33' to the working machine control unit 21'. Further, information on the height of the rotary working machine 50' (working machine 2) is also input from the height management means control unit 35 to the working machine control unit 21' via the communication unit 33'. At this time, the working machine control unit 21' calculates the height of the rotary working machine 50' and its height change using this information. Then, in order to keep the height of the rotary working machine 50' constant, it calculates the height of the rotary working machine 50' that cancels out (makes it zero) the height change. If the rotary working machine 50' is rising, it calculates the amount of change to lower the rotary working machine 50', and if the rotary working machine 50' is descending, it calculates the amount of change to raise the rotary working machine 50'. Then, the working machine control unit 21' outputs a signal to change the height of the rotary working machine 50' to the tractor control unit 11. The tractor control unit 11 controls the height of the lower link 16, which is the lifting device of the tractor 1, based on this. By controlling the height of the rotary working machine 50' to be constant in this way, the height of the tillage unit 60 becomes constant, and in the tillage operation, the ground surface of the field can be flattened.

[0065] Here, in the working machine control unit 21', either one or both of the information on the height of the rotary working machine 50' from the RTK-GNSS receiver 32 and the information on the height of the rotary working machine 50' from the height management means control unit 35 may be used according to the situation, or priorities may be determined and applied.

[0066] Thus, in the third embodiment, in addition to the second embodiment, it has the following effects. In the work implement control unit 21’, since it is possible to acquire the information of the RTK-GNSS receiver 32 and the height management means control unit 35, even when the RTK-GNSS receiver 32 cannot receive signals, it is possible to continue calculating the height and the like using the information from the height management means control unit 35. Conversely, even when the information from the height management means control unit 35 cannot be acquired, it is possible to continue calculating the height and the like using the information from the RTK-GNSS receiver 32. In this way, it is possible to improve the certainty of calculating the height and the like. Also, by using the information from the height management means control unit 35 in addition to the information from the RTK-GNSS receiver 32, it is possible to calculate more accurate height information and the like.

[0067] <Fourth Embodiment> FIG. 6 is a block diagram of a fourth embodiment of the height control system for an agricultural work implement of the present invention. In the fourth embodiment, the differences from the first and second embodiments will be mainly described, and the same reference numerals are given to the same parts, and the same explanations are omitted for the parts not particularly described.

[0068] In a configuration including a work implement 2 mounted on a tractor 1, on the tractor 1 side, a tractor control unit 11 is provided, and an antenna 31'', an RTK-GNSS receiver 32, and a communication unit 33'' are arranged. Also, on the work implement 2 side, a work implement control unit 21'' is provided. The work implement 2 is a work implement for performing agricultural work. The fourth embodiment mainly differs from the first embodiment in that it constitutes a communication terminal 304 to be described later.

[0069] The tractor control unit 11 and the tractor control box 10 are the same as those in the first embodiment.

[0070] The antenna 31'' has the same function as the antenna 31 in the first embodiment, but is provided separately from the communication terminal 304.

[0071] The communication unit 33'' changes the communication method or data format (e.g., a specific communication standard) of the signal applied by the RTK-GNSS receiver 32 to another communication method or data format (e.g., another specific communication standard) applied by the communication line 104. As a result, it becomes possible to transmit information such as height received by the RTK-GNSS receiver 32 to the work machine control unit 21.

[0072] The work machine control unit 21'' is the same as the work machine control unit 21 of the first embodiment, but the information from the RTK-GNSS receiver 32 is acquired from the communication terminal 304 on the tractor 1 side. Note that the work machine control box 20 is the same as in the first embodiment and houses the work machine control unit 21''.

[0073] The communication line 101 is the same as in the first embodiment.

[0074] The communication line 104 is a communication line connecting the communication unit 33'' and the work machine control unit 21''. The communication method of the communication line 104 can adopt a communication method applicable to the work machine control unit 21''. Note that the communication methods of the communication line 101 and the communication line 104 may be different. In this case, the work machine control unit 21'' performs communication method change processing.

[0075] The communication terminal 304 includes the RTK-GNSS receiver 32 and the communication unit 33'' and can be configured as one unit, for example, as an integrated device. The communication terminal 304 can communicate with the work machine control unit 21'' and is installed at a suitable location on the tractor 1 (e.g., near the driver's seat). On the other hand, the antenna 31'' is installed at a suitable location on the tractor 1 separately from the communication terminal 304. This makes it easy to increase the height of the antenna 31''. On the other hand, the communication terminal 304 may be configured integrally with the antenna 31''.

[0076] The communication terminal 304 may further include at least one of an operation unit and a display unit.

[0077] The operation unit of the communication terminal 304 can be provided with operation switches for operations such as push buttons. The operation unit may be provided with operation switches for setting the reception of the RTK-GNSS receiver 32, setting the control by the work machine control unit 21'', and changing the display of the display unit. Further, by operating the operation unit, an operation signal may be transmitted to the work machine control unit 21'', and the actuator provided in the work machine 2 may be operable under the control of the work machine control unit 21''. Examples of the actuator include cylinders such as hydraulic cylinders and electro-hydraulic cylinders, motors, and power using solenoids.

[0078] The display unit of the communication terminal 304 can be provided with means for displaying necessary information by a display screen using liquid crystal, organic EL, LED, etc. For example, it is for displaying height information acquired by the RTK-GNSS receiver 32, reception information, etc. Also, information may be acquired from the work machine control unit 21'' and displayed. The communication terminal 304 may adopt a touch panel method for the display screen. Thereby, a configuration including an operation unit and a display unit can be constructed. For example, general-purpose portable terminals such as smartphones and tablet computers can be applied. Thereby, it becomes possible to add the functions of the RTK-GNSS receiver 32 and the communication unit 33'' to an existing terminal.

[0079] As a work machine applicable to the fourth embodiment, the rotary work machine 50 shown in FIG. 2 of the first embodiment can be used. In this case, the antenna 31'' can be installed instead of the height control unit 301. And the communication terminal 304 can be arranged near the driver's seat on the tractor 1 side.

[0080] For example, when it is desired to flatten the ground surface of the field, if the antenna 31 is changed to the antenna 31'' and the work machine control unit 21 is changed to the work machine control unit 21'', the processing flow is the same as that of the first embodiment.

[0081] Thus, in the fourth embodiment, in addition to the first embodiment, it has the following effects. By providing the communication terminal 304 with the functions of the RTK-GNSS receiver 32 and the communication unit 33'', it can be provided in common with the remote control function of the communication terminal 304. Thereby, it is possible to reduce costs by reducing the number of additional devices.

[0082] As described above, the embodiments of the present invention have been described. However, the present invention is not limited to the above embodiments, and various modifications other than those described above are also included. For example, it is not limited to those having all the configurations provided in the above-described embodiments. Also, it is possible to delete a part of the configuration of a certain embodiment or replace it with another configuration.

[0083] For example, although the RTK-GNSS receiver 32 that receives signals from GNSS satellites has been described, instead of this, a satellite positioning system that receives signals from navigation satellites other than the RTK-GNSS method and acquires height information may be used (for example, CLAS positioning signals, etc.). In this case, the height management means control unit 35 in FIG. 5 of the third embodiment becomes a means for detecting the height provided to acquire height information by other means.

[0084] Also, in the above embodiment, the communication lines 101, 102, 102', 103, 104 have been shown, but wireless communication may be applied instead of these communication lines. In this case, it is converted to a communication method suitable for wireless communication. In particular, for the communication lines 101 and 104 between the tractor 1 and the working machine 2, it is effective because there is no need to connect the communication line when the tractor 1 and the working machine 2 are attached and detached. Also, for the communication line 104, the wireless communication method of the communication terminal 304 can be used as it is. As the wireless communication, for example, BLE (Bluetooth Low Energy) etc. can be applied.

[0085] In the above-described embodiment, as an example of the working machine 2, the examples of the rotary working machines 50 and 50' were shown. However, in addition to these, it is applicable to the working machine 2 attached to the tractor 1 such as a rotary tiller or a ridging machine. It is particularly effective for a working machine 2 that requires height control.

[0086] Also, the display unit 12 and the operation unit 13 described in the first embodiment can be similarly applied in the second to fourth embodiments.

[0087] This specification also includes the disclosure of the following aspects. (Aspect 1) In a height control system for an agricultural working machine applied to a working machine attached to a tractor for performing agricultural work, it includes a tractor control unit provided in the tractor, a working machine control unit provided in the working machine, an antenna disposed in the tractor, and a receiver disposed in the tractor. The working machine control unit acquires the height information of the tractor from the receiver based on the signal received by the antenna, calculates the height of the working machine with respect to the tractor based on the acquired information, and transmits a signal for controlling the height of the working machine to the tractor control unit based on the calculated information. The tractor control unit controls the height of the working machine with respect to the tractor based on the received signal for controlling the height. A height control system for an agricultural working machine characterized by this.

[0088] (Aspect 2) In a height control system for an agricultural working machine applied to a working machine attached to a tractor for performing agricultural work, it includes a tractor control unit provided in the tractor, a working machine control unit provided in the working machine, an antenna disposed in the working machine, and a receiver disposed in the working machine. The working machine control unit acquires the height information of the working machine from the receiver based on the signal received by the antenna, calculates the height of the working machine with respect to the tractor based on the acquired information, and transmits a signal for controlling the height of the working machine to the tractor control unit based on the calculated information. The height control system for agricultural working machines is characterized in that the tractor control unit controls the height of the working machine with respect to the tractor based on the received height control signal.

[0089] (Aspect 3) In a height control system for agricultural working machines applied to a working machine mounted on a tractor for performing agricultural work, it includes a tractor control unit provided in the tractor, a working machine control unit provided in the working machine, an antenna arranged on the working machine, a receiver arranged on the working machine, and a height management means control unit arranged on the working machine. The height management means control unit detects the height of the working machine by means other than the signal received by the antenna. The working machine control unit acquires information on the height of the working machine from the receiver based on the signal received by the antenna, and also acquires information on the height of the working machine from the height management means control unit. Based on the acquired information, it calculates the height of the working machine with respect to the tractor, and based on the calculated information, it transmits a signal for controlling the height of the working machine to the tractor control unit. The height control system for agricultural working machines is characterized in that the tractor control unit controls the height of the working machine with respect to the tractor based on the received height control signal.

[0090] (Aspect 4) In the height control system for agricultural working machines according to Aspect 1, it includes a communication unit arranged on the tractor, and the communication unit has a function of converting information from the receiver into a communication method applied between the tractor control unit and the working machine control unit. The height control system for agricultural working machines is characterized in that the antenna, the receiver, and the communication unit are configured as one unit.

[0091] (Aspect 5) In the height control system for agricultural working machines according to Aspect 1, The receiver disposed on the tractor is provided in a communication terminal capable of communicating with the work implement control unit and having at least one of an operation unit and a display unit, and is characterized by a height control system for agricultural work implements.

[0092] (Aspect 6) In the height control system for agricultural work implements according to Aspect 2, it includes a communication unit disposed on the work implement, and the communication unit has a function of converting information from the receiver into a communication method applied between the tractor control unit and the work implement control unit. The receiver and the communication unit are configured as one unit, and the antenna is provided at a position higher than the unit, and is characterized by a height control system for agricultural work implements.

[0093] (Aspect 7) In the height control system for agricultural work implements according to any one of Aspects 1 to 6, the antenna and the receiver are an antenna and a receiver for RTK-GNSS positioning, and are characterized by a height control system for agricultural work implements.

Explanation of Reference Numerals

[0094] 1 Tractor 2 Work Implement 11 Tractor Control Unit 21, 21’, 21’’ Work Implement Control Unit 31, 31’, 31’’ Antenna 32 RTK-GNSS Receiver 33, 33’, 33’’ Communication Unit 35 Height Management Means Control Unit 50, 50’ Rotary Work Implement 52 Frame 60 Cultivation Unit 81 Fixing Member 301 Height Control Unit 302 Height Control Unit 303 Height Control Unit 304 Communication Terminal

Claims

1. In a height control system for an agricultural work machine applied to a work machine mounted on a tractor for performing agricultural work, comprising a tractor control unit provided in the tractor, a work machine control unit provided in the work machine, an antenna disposed on the tractor, and a receiver disposed on the tractor, the work machine control unit acquires information on the height of the tractor from the receiver based on a signal received by the antenna, calculates the height of the work machine with respect to the tractor based on the acquired information, and transmits a signal for controlling the height of the work machine to the tractor control unit based on the calculated information, The tractor control unit controls the height of the work machine with respect to the tractor based on a received signal for controlling the height. A height control system for an agricultural work machine characterized by this.

2. In a height control system for an agricultural work machine applied to a work machine mounted on a tractor for performing agricultural work, comprising a tractor control unit provided in the tractor, a work machine control unit provided in the work machine, an antenna disposed on the work machine, and a receiver disposed on the work machine, the work machine control unit acquires information on the height of the work machine from the receiver based on a signal received by the antenna, calculates the height of the work machine with respect to the tractor based on the acquired information, and transmits a signal for controlling the height of the work machine to the tractor control unit based on the calculated information, The tractor control unit controls the height of the work machine with respect to the tractor based on a received signal for controlling the height. A height control system for an agricultural work machine characterized by this.

3. In a height control system for an agricultural work machine applied to a work machine mounted on a tractor for performing agricultural work, comprising a tractor control unit provided in the tractor, a work machine control unit provided in the work machine, an antenna disposed on the work machine, a receiver disposed on the work machine, and a height management means control unit disposed on the work machine, the height management means control unit detects the height of the work machine by means other than the signal received by the antenna, the work machine control unit acquires information on the height of the work machine from the receiver based on a signal received by the antenna, acquires information on the height of the work machine from the height management means control unit, calculates the height of the work machine with respect to the tractor based on the acquired information, and transmits a signal for controlling the height of the work machine to the tractor control unit based on the calculated information, The height control system for an agricultural work machine is characterized in that the tractor control unit controls the height of the work machine with respect to the tractor based on a signal for controlling the received height.

4. In the height control system for an agricultural work machine according to Claim 1, it includes a communication unit arranged on the tractor, and the communication unit has a function of converting information from the receiver into a communication method applied between the tractor control unit and the work machine control unit. The height control system for an agricultural work machine is characterized in that the antenna, the receiver, and the communication unit are configured as one unit.

5. In the height control system for an agricultural work machine according to Claim 1, the receiver arranged on the tractor is provided in a communication terminal that can communicate with the work machine control unit and has at least one of an operation unit and a display unit. The height control system for an agricultural work machine is characterized by this.

6. In the height control system for an agricultural work machine according to Claim 2, it includes a communication unit arranged on the work machine, and the communication unit has a function of converting information from the receiver into a communication method applied between the tractor control unit and the work machine control unit. The height control system for an agricultural work machine is characterized in that the receiver and the communication unit are configured as one unit, and the antenna is provided at a position higher than the unit.

7. In the height control system for an agricultural work machine according to any one of Claims 1 to 6, the height control system for an agricultural work machine is characterized in that the antenna and the receiver are an antenna and a receiver for RTK-GNSS positioning.

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