Control system, control method, and working machine

Abstract

To provide a control system for automatically adjusting an attitude of a work tool to multiple attitudes.SOLUTION: A control system of a work machine that has a work machine including a work tool and a movable support part for varying an attitude of the work tool, comprises a controller having a storage part for storing at least three kinds of target attitudes including a first attitude. The controller selects any one of the three kinds of the target attitudes on the basis of a command signal operating the attitude of the work tool and a detection signal showing the present attitude of the work tool, and sets as the target attitude of the work machine, and controls the movable support part.SELECTED DRAWING: Figure 12

Description

Technical Field

[0001] The present disclosure relates to a control system, a control method, and a working machine.

Background Art

[0002] Patent Document 1 discloses a wheel loader that automatically adjusts a bucket to a horizontal posture when an operation lever is operated to a holding position.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a wheel loader as an example of a working machine, for example, in a bucket which is an example of a working tool, typical postures often used include, in addition to the horizontal posture, a carrying posture, a dumping posture, a grounding posture, and the like. However, the wheel loader described in Patent Document 1 has a problem that the posture of the bucket cannot be automatically adjusted to a plurality of typical postures.

[0005] The present disclosure has been made in view of the above circumstances, and an object thereof is to provide a control system, a control method, and a working machine capable of automatically adjusting the posture of a working tool to a plurality of postures.

Means for Solving the Problems

[0006] To solve the above problems, a first aspect of the present disclosure is a control system for a working machine having a working tool and a movable support portion that changes the posture of the working tool, the control system including a controller having a storage unit that stores at least three types of target postures. The controller selects any one of the at least three types of target postures as the target posture of the working tool based on a command signal for operating the posture of the working tool and a detection signal indicating the current posture of the working tool, and controls the movable support portion.

[0007] Further, a second aspect of the present disclosure is a control system for a working machine having a working tool and a movable support portion that changes the posture of the working tool, the control system including a controller having a storage unit that stores at least three types of target postures including a first posture. When the controller receives a command signal for operating the posture of the working tool, the controller controls the movable support portion with the first posture as the target posture of the working tool. When the controller continuously receives the command signal repeatedly within a predetermined time, the controller selects a target posture different from the first posture among the at least three types of target postures as the target posture of the working tool, and controls the movable support portion.

[0008] Further, a third aspect of the present disclosure is a control method for a working machine having a working tool and a movable support portion that changes the posture of the working tool, the control method including the following steps. A first step is to store at least three types of target postures. A second step is to select any one of the at least three types of target postures based on a command signal for operating the posture of the working tool and a detection signal indicating the current posture of the working tool. A third step is to control the movable support portion with the selected target posture as the target posture of the working tool.

[0009] Moreover, a fourth aspect of the present disclosure is a control method for a working machine having a working tool and a movable support portion that changes the posture of the working tool, the method comprising the following steps. The first step is to store at least three types of target postures including a first posture. The second step is to select the first posture as the target posture when a command signal for operating the posture of the working tool is received. The third step is to select a target posture different from the first posture among at least three types of target postures when the command signal is continuously received repeatedly within a predetermined time. The fourth step is to control the movable support portion with the selected target posture as the target posture of the working tool.

[0010] Moreover, a fifth aspect of the present disclosure is a working machine having a working tool and a movable support portion that changes the posture of the working tool, the working machine comprising a controller that controls the movable support portion. The controller includes a storage unit that stores at least three types of target postures. The controller selects any one of at least three types of target postures based on a command signal for operating the posture of the working tool and a detection signal indicating the current posture of the working tool, sets the selected target posture as the target posture of the working tool, and controls the movable support portion.

[0011] Moreover, a sixth aspect of the present disclosure is a working machine having a working tool and a movable support portion that changes the posture of the working tool, the working machine comprising a controller that controls the movable support portion. The controller includes a storage unit that stores at least three types of target postures including a first posture. When the controller receives a command signal for operating the posture of the working tool, the controller controls the movable support portion with the first posture as the target posture of the working tool. When the controller continuously receives the command signal repeatedly within a predetermined time, the controller selects a target posture different from the first posture among at least three types of target postures, sets the selected target posture as the target posture of the working tool, and controls the movable support portion.

Advantages of the Invention

[0012] According to each aspect of the present disclosure, the posture of the working tool can be automatically adjusted to a plurality of postures.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

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Figure 14

MODE FOR CARRYING OUT THE INVENTION

[0014] Hereinafter, embodiments according to the present disclosure will be described with reference to the drawings. In each figure, the same or corresponding components are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

[0015] In this embodiment, a local coordinate system is set for the working machine 1, and the positional relationship of each part will be described with reference to the local coordinate system. In the local coordinate system, the first axis extending in the left-right direction (vehicle width direction) of the working machine 1 is defined as the X axis, the second axis extending in the front-rear direction of the working machine 1 is defined as the Y axis, and the third axis extending in the up-down direction of the working machine 1 is defined as the Z axis. The X axis and the Y axis are perpendicular to each other. The Y axis and the Z axis are perpendicular to each other. The Z axis and the X axis are perpendicular to each other. The +X direction is the right direction, and the -X direction is the left direction. The +Y direction is the front direction, and the -Y direction is the rear direction. The +Z direction is the up direction, and the -Z direction is the down direction.

[0016] <The First Embodiment> [Overview of the Working Machine] FIGS. 1 to 5 are side views showing the working machine 1 according to the first embodiment. The working machine 1 according to the first embodiment is, for example, a wheel loader. In the following description, the working machine 1 is appropriately referred to as the wheel loader 1.

[0017] As shown in FIG. 1, the wheel loader 1 includes a vehicle body 2, a cab 3, a traveling device 4, and a working device 10. The wheel loader 1 travels on the work site by the traveling device 4. The wheel loader 1 performs work at the work site using the working device 10. The wheel loader 1 can perform operations such as excavation work, loading work, transportation work, and snow removal work using the working device 10.

[0018] The cab 3 is supported by the vehicle body 2. Inside the cab 3, a driver's seat 31 on which an operator sits, an operation device 32 described later, and a display input unit 34 are arranged.

[0019] The traveling device 4 has rotatable wheels 5. The wheels 5 support the vehicle body 2. The wheel loader 1 can travel on the road surface (or ground) RS by the traveling device 4. In FIG. 1, only the left front wheel 5F and the rear wheel 5R are shown.

[0020] The work machine 10 is supported by the vehicle body 2. The work machine 10 is composed of a bucket 12 as an example of a working tool and a movable support portion 17 that changes the position and posture of the bucket 12. In the example shown in FIG. 1, the movable support portion 17 includes a boom 11, a boom cylinder 13, a bucket cylinder 14, a bell crank 15, and a link 16.

[0021] The boom 11 is rotatably supported with respect to the vehicle body 2 and moves in the vertical direction as shown in FIGS. 1 to 5 according to the extension and contraction of the boom cylinder 13. The boom cylinder 13 is an actuator that generates power for moving the boom 11. One end portion is connected to the vehicle body 2 and the other end portion is connected to the boom 11. When the operator operates a boom operating device (not shown) included in the operating device 32, the boom cylinder 13 extends and contracts. Thereby, the boom 11 moves in the vertical direction. The boom cylinder 13 is, for example, a hydraulic cylinder.

[0022] The bucket 12 has a cutting edge 12T and is a working tool for excavating and loading objects to be excavated such as earth and sand. The bucket 12 is rotatably connected to the boom 11 and is also rotatably connected to one end portion of the link 16. The other end portion of the link 16 is rotatably connected to one end portion of the bell crank 15. The center portion of the bell crank 15 is rotatably connected to the boom 11, and the other end portion is rotatably connected to one end portion of the bucket cylinder 14. The other end portion of the bucket cylinder 14 is rotatably connected to the vehicle body 2. The bucket 12 is actuated by the power generated by the bucket cylinder 14. The bucket cylinder 14 is an actuator that generates power for moving the bucket 12. When the operator operates the bucket operating device 33, the bucket cylinder 14 extends and contracts. Thereby, the bucket 12 swings. The bucket cylinder 14 is, for example, a hydraulic cylinder. The cutting edge 12T has a shape such as a mountain edge or a flat edge and is detachably attached to the end portion of the bucket 12.

[0023] In this embodiment, as shown in FIG. 2, the posture of the bucket 12 with the cutting edge 12T facing downward is referred to as the dump posture. The dump posture is, for example, a posture (dumping posture) in which the excavated material in the bucket 12 can be loaded onto a transport vehicle or the like. Further, as shown in FIG. 3, the posture of the bucket 12 with the cutting edge 12T facing upward is referred to as the tilt posture (holding posture). The tilt posture is, for example, a posture (transport posture) in which the excavated material can be held in the bucket 12. Further, as shown in FIG. 4, the posture of the bucket 12 with the cutting edge 12T facing in the horizontal direction (including substantially the horizontal direction) with respect to the road surface RS is referred to as the excavation posture (or the traveling posture during excavation). The excavation posture is, for example, a posture when starting to excavate an excavation target such as earth and sand or when traveling toward the excavation target (or a posture suitable for starting excavation or traveling). Further, as shown in FIG. 5, the posture of the bucket 12 with the cutting edge 12T in contact with the road surface RS is referred to as the grounding posture. The wheel loader 1 starts excavating an excavation target located in front by, for example, setting the bucket 12 in the excavation posture (or a posture in which the cutting edge 12T is lower than the road surface RS from the excavation posture) and traveling in the forward direction. In the wheel loader 1, the excavation posture can also be called the horizontal posture because the cutting edge direction is substantially horizontal with respect to the road surface RS.

[0024] [Configuration of Control System] FIG. 6 is a block diagram showing a configuration example of the control system of the wheel loader 1 according to the first embodiment. As shown in FIG. 6, the wheel loader 1 includes a power source 201, a PTO (Power Take Off) 202, a hydraulic pump 203, a control valve 200, an operation device 32, a display input unit 34, and a controller 100.

[0025] The power source 201 generates a driving force for operating the work machine. Examples of the power source include an internal combustion engine and an electric motor.

[0026] The PTO 202 transmits at least a part of the driving force of the power source 201 to the hydraulic pump 203. The PTO 202 distributes the driving force of the power source 201 to the traveling device 4 and the hydraulic pump 203.

[0027] The hydraulic pump 203 is driven by the power source 201 and discharges hydraulic oil. At least a part of the hydraulic oil discharged from the hydraulic pump 203 is supplied to each of the boom cylinder 13 and the bucket cylinder 14 via the control valve 200. The control valve 200 controls the flow rate and direction of the hydraulic oil supplied from the hydraulic pump 203 to each of the boom cylinder 13 and the bucket cylinder 14. The working machine 10 operates by the hydraulic oil from the hydraulic pump 203.

[0028] The operating device 32 is arranged inside the cab 3. The operating device 32 is operated by the operator. The operator operates the operating device 32 to adjust the traveling direction and traveling speed of the wheel loader 1, switch between forward and reverse, and operate the working machine 10. The operating device 32 includes, for example, a steering, a shift lever, an accelerator pedal, a brake pedal, and a bucket operating device (an example of a working tool operating device) 33 for operating the bucket 12 of the working machine 10. The bucket operating device 33 outputs a command signal for operating the posture of the bucket 12. The display input unit 34 is composed of a combination of an input device and a display device, an input display device such as a touch panel, etc. The operator uses the display input unit 34 to set, for example, a stored value of a target position or a target posture in the control of the working machine 10 described later.

[0029] FIG. 7 and FIG. 8 are configuration diagrams showing a bucket operation device 33 according to the first embodiment. Note that FIG. 7 shows an example in which the bucket operation device 33 has one switch 33b1 on an operation lever 33L, and FIG. 8 shows an example in which the bucket operation device 33 has two switches 33b1 and 33b2 on the operation lever 33L. As shown in FIGS. 7 and 8, the bucket operation device 33 includes an electric operation lever 33L that is operable in a direction from a tilting position A1 (first control position) to a tilting position E1 (second control position) (E1←D1←C1→B1→A1) in the front-rear direction with respect to a neutral position (C1). The tilting positions A1 and E1 are positions where the operation lever 33L reaches the stroke ends in the rearward and forward directions, respectively. The bucket operation device 33 has a mechanism that automatically returns the position of the operation lever 33L to the neutral position (C1) when an operation force equal to or greater than a certain value is not applied to the operation lever 33L. In the present embodiment, an operation of tilting the position of the operation lever 33L to the tilting position A1 or the tilting position E1 is referred to as a tilting holding operation. Further, an operation of tilting the position of the operation lever 33L to the tilting position A1 is referred to as a tilt-side tilting holding operation. Further, an operation of tilting the position of the operation lever 33L to the tilting position E1 is referred to as a dump-side tilting holding operation.

[0030] The bucket operation device 33 outputs a control signal according to the tilting direction and tilting amount of the operation lever 33L. Further, the bucket operation device 33 outputs a predetermined operation pattern signal indicating that the operation lever 33L has been tilted to the tilting positions A1 and E1. Further, the bucket operation device 33 outputs a signal indicating whether the switch 33b1 or the switch 33b2 is pressed. In the present embodiment, an operation of pressing the switch 33b1 or the switch 33b2 may be used as a tilting holding operation. In this case, the bucket operation device 33 may be configured using a PPC (Pressure Proportional Control) valve.

[0031] Note that when the operator's hand leaves the operation lever 33L, the operation lever returns to the neutral state (C1). However, the controller 100 described later can perform control by, for example, assuming that the virtual tilting hold state continues until the position and posture of the working machine 10 reach a predetermined state.

[0032] In addition, the wheel loader 1 includes a working machine load sensor 71, a boom angle sensor 72, and a bucket angle sensor 73.

[0033] The working machine load sensor 71 detects the load applied to the working machine 10. The working machine load sensor 71 is, for example, a load measurement device such as a strain gauge or a load cell arranged on at least a part of the working machine 10. The load data detected by the working machine load sensor 71 is output to the controller 100. Note that the load applied to the working machine 10 may be detected using, for example, a hydraulic pressure sensor that detects the pressure of the hydraulic oil that drives the boom cylinder 13 or a hydraulic pressure sensor that detects the pressure of the hydraulic oil that drives the bucket cylinder 14. In this case, the load applied to the working machine 10 changes between the state where the excavated material is held in the bucket 12 and the state where it is not held. The working machine load sensor 71 can detect the presence or absence of the excavated material held in the bucket 12 by detecting the change in the load applied to the working machine 10.

[0034] The boom angle sensor 72 detects the angle of the boom 11 with respect to the vehicle body 2 and outputs the detection data to the controller 100. The boom angle sensor 72 is, for example, an angle sensor arranged at the connection part between the vehicle body 2 and the boom 11. Note that the angle of the boom 11 may be calculated from the stroke amount of the boom cylinder 13.

[0035] The bucket angle sensor 73 is a sensor for detecting the angle of the bucket 12. The bucket angle sensor 73 is, for example, an angle sensor disposed at the connection portion between the boom 11 and the bell crank 15. The bucket angle sensor 73 detects the angle of the bell crank 15 with respect to the boom 11 and outputs the detected data to the controller 100. Based on the angle of the boom 11 with respect to the vehicle body 2 detected by the boom angle sensor 72 and the angle of the bell crank 15 with respect to the boom 11 detected by the bucket angle sensor 73, the angle of the bucket 12 with respect to the boom 11 (and the vehicle body 2) can be calculated. Note that the angle of the bucket 12 with respect to the boom 11 may be detected, for example, by using a sensor that detects the angle of the bucket 12 with respect to the boom 11 at the connection portion between the bucket 12 and the boom 11. Further, the angle of the bell crank 15 with respect to the boom 11 and the angle of the bucket 12 with respect to the boom 11 may be calculated from the stroke amount of the boom cylinder 13 and the stroke amount of the bucket cylinder 14.

[0036] [Configuration of Controller] FIG. 9 is a configuration diagram showing the controller 100 of the wheel loader 1 according to the first embodiment. The controller 100 is configured by using, for example, an FPGA (Field Programmable Gate Array) or a microcomputer having a processor, a main storage device, an auxiliary storage device, an input / output device, and the like. The controller 100 includes, as a functional configuration composed of hardware or a combination of hardware and software such as a program, an operation signal detection unit 101, a boom angle acquisition unit 102, a bucket angle calculation unit 104, a storage unit 105, a target bucket angle determination unit 107, a bucket ground detection unit 112, and a bucket cylinder control unit 109.

[0037] The controller 100 of this embodiment is a device that controls the working machine 10 having the bucket 12 and the movable support portion 17 that changes the position and posture of the bucket 12. Then, based on the command signal for operating the posture of the bucket 12 and the detection signal indicating the current posture of the bucket 12, the controller 100 selects any one of at least three types of target postures as the target posture of the bucket 12 and controls the movable support portion 17. The command signal for operating the posture of the bucket 12 includes a control signal corresponding to the tilting direction and tilting amount of the operation lever 33L output by the bucket operating device 33, and a control signal indicating that a tilting holding operation has been performed on the bucket operating device 33 output by the operation signal detection unit 101. The detection signal indicating the current posture of the bucket 12 is a detection signal indicating the current bucket angle output by the bucket angle calculation unit 104.

[0038] Note that FIG. 9 shows only the configuration corresponding to the control according to the operation of the bucket operating device 33 included in the operation device 32 (operation unit) among the plurality of functions of the controller 100. Also, in the operation example of the controller 100 described later, among the controls according to the operation of the bucket operating device 33, the case where a tilting holding operation is performed on the operation lever 33L of the bucket operating device 33 shown in FIGS. 7 and 8 will be described.

[0039] The operation signal detection unit 101 receives the operation signal of the bucket operating device 33 in the operation device 32, and outputs the result of detecting whether a tilting holding operation for tilting the position of the operation lever 33L to the tilting position A1 or the tilting position E1, or whether a tilting holding operation is performed on the switch 33b1, as a control signal indicating that the tilting holding operation has been performed to the target bucket angle determination unit 107 and the bucket cylinder control unit 109. Note that in this embodiment, the command signal for operating the posture of the bucket 12 includes the following first command signal and second command signal output by the operation signal detection unit 101.

[0040] The first command signal is, for example, a signal output when the operation lever 33L is tilt-held at the tilt position A1 (the first control position). The second command signal is, for example, a signal output when the operation lever 33L is tilt-held at the tilt position E1 (the second control position).

[0041] Alternatively, the first command signal is, for example, a signal output when the operation lever 33L is operated to the tilt position B1 (the direction of the first control position) and the switch 33b1 is operated. The second command signal is, for example, a signal output when the operation lever 33L is operated to the tilt position D1 (the direction of the second control position) and the switch 33b1 is operated.

[0042] Alternatively, the first command signal is, for example, a signal output when the switch 33b1 (the first switch) is operated. The second command signal is a signal output when the switch 33b2 (the second switch) is operated.

[0043] The boom angle acquisition unit 102 receives the data detected by the boom angle sensor 72 and acquires the current boom angle. The boom angle acquisition unit 102 outputs the acquired current boom angle data to the target bucket angle determination unit 107 and the bucket ground detection unit 112. The current boom angle data may be, for example, data indicating the current boom cylinder length.

[0044] The bucket angle calculation unit 104 receives the data detected by the boom angle sensor 72 and the data detected by the bucket angle sensor 73, and calculates the current bucket angle. The bucket angle calculation unit 104 outputs the calculated current bucket angle data to the target bucket angle determination unit 107, the bucket cylinder control unit 109, and the bucket ground detection unit 112. The current bucket angle data may be, for example, data indicating the current bucket cylinder length.

[0045] The memory unit 105 stores, as stored values, the set values of at least three types of target postures of the bucket 12 set using the display input unit 34. In the present embodiment, the at least three types of target postures include a first posture, a second posture, and a third posture. Alternatively, in a second embodiment described later, the at least three types of target postures include the first posture. Also, the initial value of the first posture can be, for example, the horizontal posture of the bucket 12. Also, the initial value of the second posture can be, for example, the carrying posture of the bucket 12. Also, the initial value of the third posture can be, for example, the soil discharge posture or the grounding posture of the bucket 12. The operator can change or initialize the set values of these target postures using the display input unit 34.

[0046] The target bucket angle determination unit 107 selects one target posture from the set values of at least three types of target postures stored in the memory unit 105 based on the output signal of the operation signal detection unit 101, the output signal of the bucket angle calculation unit 104, and the set value of the target posture set in the memory unit 105. The target bucket angle determination unit 107 determines the target bucket angle based on the selected target posture and the output signal (boom angle) of the boom angle acquisition unit 102. Since the movable range of the posture of the bucket 12 changes according to the angle of the boom 11 (boom angle), the posture of the bucket 12 is determined based on the target posture and the boom angle. Note that the data indicating the target bucket angle may be, for example, data indicating the target bucket cylinder length which is the target value of the bucket cylinder length. The target bucket angle determination unit 107 outputs the selected target posture data to the bucket cylinder control unit 109. The target bucket angle determination unit 107 outputs the determined target bucket angle to the bucket cylinder control unit 109.

[0047] Note that when the target bucket angle determination unit 107 receives the first command signal from the operation signal detection unit 101, it selects either the first posture or the second posture as the target posture. Also, when the target bucket angle determination unit 107 receives the second command signal from the operation signal detection unit 101, it selects either the first posture or the third posture as the target posture.

[0048] In this embodiment, the bucket 12 is rotatable between a first posture region and a second posture region. The first posture region is a posture region between the first posture and the second posture, and the second posture region is a posture region between the first posture and the third posture. When the target bucket angle determination unit 107 receives the first command signal from the operation signal detection unit 101 and the current posture of the bucket 12 is in the second posture region, the first posture is selected as the target posture. Further, when the target bucket angle determination unit 107 receives the second command signal from the operation signal detection unit 101 and the current posture of the bucket 12 is in the first posture region, the first posture is selected as the target posture.

[0049] The bucket ground detection unit 112 detects whether the bucket 12 is grounded on the road surface (ground) RS based on the boom angle output by the boom angle acquisition unit 102, the bucket angle calculated by the bucket angle calculation unit 104, and the load of the working machine 10 detected by the working machine load sensor 71. The bucket ground detection unit 112 estimates the distance between the bucket 12 and the road surface RS based on, for example, the boom angle and the bucket angle, and detects that the bucket 12 is grounded when the working machine load sensor 71 detects an increase in a certain load. The bucket ground detection unit 112 outputs the detection result to the bucket cylinder control unit 109.

[0050] When a predetermined tilting holding operation is performed on the bucket operating device 33, the bucket cylinder control unit 109 outputs a bucket cylinder command so as to achieve the target posture selected by the target bucket angle determination unit 107 based on the command signal for operating the posture of the bucket 12 and the detection signal indicating the current posture of the bucket 12. The bucket cylinder control unit compares the current bucket angle calculated by the bucket angle calculation unit 104 with the target bucket angle determined by the target bucket angle determination unit 107, and outputs a bucket cylinder command so that the current bucket angle becomes the target bucket angle. The bucket cylinder control unit 109 outputs a bucket cylinder command to control the control valve 200. The control valve 200 drives the bucket cylinder 14 based on the bucket cylinder command to control the movable support portion 17.

[0051] [Operation Example of Bucket] FIG. 10 is a schematic diagram showing an operation example of the bucket 12 according to the first embodiment. In FIG. 10, the case where the bucket 12 is in a horizontal state (horizontal posture) is shown as the bucket 12-1. The state where the bucket 12 is tilted to the maximum (this state is referred to as the tilt end) is shown as the bucket 12-2. The state where the bucket 12 is dumped to the maximum (this state is referred to as the dump end) is shown as the bucket 12-3. However, the posture of the dump end is either the state where the bucket 12 is dumped to the maximum (shown as the bucket 12-3a) or the state where the bucket 12 is grounded (shown as the bucket 12-3b).

[0052] In the following description of the operation example, the case where the first posture is the horizontal posture, the second posture is the tilt end, and the third posture is the dump end will be described. Note that the bucket 12-1-2 is the posture between the bucket 12-1 in the first posture and the bucket 12-2 in the second posture. The bucket 12-1-3 is the posture between the bucket 12-1 in the first posture and the bucket 12-3 in the third posture.

[0053] [Operation Example of Controller] FIG. 11 is a flowchart showing an operation example of the controller 100 according to the first embodiment. By the process shown in FIG. 11, the controller 100 (bucket cylinder control unit 109) controls the bucket posture.

[0054] FIG. 11 is a flow that is repeatedly executed at a predetermined cycle. Note that FIG. 11 shows the process on the tilt side, and the process on the dump side is the process in which "(tilt side)" or "(tilt end)" in the parentheses is replaced with "(dump side)" or "(dump end)" in the parentheses.

[0055] In the process shown in FIG. 11, the controller 100 first determines whether or not a tilting holding operation to the tilt side (dump side) has been detected (S101). If the tilting holding operation has not been detected (S101: No), the controller 100 ends the process shown in FIG. 11. If the tilting holding operation has been detected (S101: Yes), the controller 100 determines whether the current posture of the bucket 12 is on the dump side (tilt side) rather than the horizontal posture based on the current bucket angle data (S102). If the current posture of the bucket 12 is on the dump side (tilt side) rather than the horizontal posture (S102: Yes), the controller 100 determines a target bucket angle at which the bucket 12 becomes horizontal according to the current boom angle (S103). If the current posture of the bucket 12 is not on the dump side (tilt side) rather than the horizontal posture (S102: No), the controller 100 determines a target bucket angle at which the posture of the bucket 12 becomes the tilt end (dump end) state according to the current boom angle (S104). Next, the controller 100 outputs a command so that the current bucket angle becomes the target bucket angle (S105). Next, the controller 100 determines whether or not a lever operation to the dump side (tilt side) has been detected (S106). If a lever operation to the dump side (tilt side) has been detected (S106: Yes), the controller 100 aborts the process (S107). If a lever operation to the dump side (tilt side) has not been detected (S106: No), the controller 100 ends the process shown in FIG. 11.

[0056] Through the above process, the controller 100 controls the movable support portion 17 so that the posture of the bucket 12 becomes the target bucket posture. In the present embodiment, when the bucket posture is on the dump side (tilt side) rather than the horizontal posture (first posture), the bucket posture can be adjusted to the horizontal posture (first posture) by the tilting holding operation to the tilt side (dump side).

[0057] Also, when the bucket posture is on the tilt side (dump side) rather than the horizontal posture (first posture), the controller 100 can adjust to the tilt end (dump end) by the tilting holding operation to the tilt side (dump side).

[0058] (Function and Effect) According to the present embodiment as described above, by performing a predetermined tilting holding operation on the bucket operating device 33, the posture of the working tool can be automatically adjusted to a plurality of postures.

[0059] <Second Embodiment> Next, an operation example of the controller 100 according to the second embodiment will be described in detail with reference to FIGS. 12 to 14. Since the configuration of the controller 100 is the same as that of the first embodiment shown in FIG. 9, the description thereof will be omitted.

[0060] [Operation Example of Controller] FIGS. 12 to 14 are flowcharts showing an operation example of the controller 100 according to the second embodiment. By the processes shown in FIGS. 12 to 14, the controller 100 (bucket cylinder control unit 109) controls the bucket posture.

[0061] FIG. 12 is a main flow repeatedly executed at a predetermined cycle. FIG. 13 shows the content of process 1 (process when a tilting holding operation is detected once) executed in S202 and terminated in S206. FIG. 14 shows the content of process 2 (process when, for example, a second tilting holding operation is detected within a predetermined time after the first tilting holding operation is detected) executed in S207. FIGS. 12 to 14 show the processes on the tilt side. For the processes on the dump side, “tilt side” or “tilt end” in “( )” is replaced with “(dump side)” or “(dump end)”, and the process with the determination of (S405) is added. However, there is no problem in executing the determination process of S405 in the processes on the tilt side.

[0062] In the process shown in FIG. 12, the controller 100 first determines whether or not it has detected a tilting hold operation toward the tilt side (dump side) (S201). If it has not detected a tilting hold operation (S201: No), the controller 100 ends the process shown in FIG. 12. If it has detected a tilting hold operation (S201: Yes), the controller 100 starts Process 1 (FIG. 13) (S202). Thereafter, Process 1 is executed until Process 1 is aborted within Process 1 or until it is aborted in S206.

[0063] In Process 1 shown in FIG. 13, the controller 100 first determines whether or not the current posture of the bucket 12 is on the dump side (tilt side) rather than the horizontal posture based on the current bucket angle data (S301). If the current posture of the bucket 12 is not on the dump side (tilt side) rather than the horizontal posture (S301: No), the controller 100 ends Process 1 shown in FIG. 13. If the current posture of the bucket 12 is on the dump side (tilt side) rather than the horizontal posture (S301: Yes), the controller 100 determines a target bucket angle at which the posture of the bucket 12 becomes the horizontal posture according to the current boom angle (S302). Next, the controller 100 outputs a command so that the current bucket angle becomes the target bucket angle (S303). Next, the controller 100 determines whether or not it has detected a lever operation toward the dump side (tilt side) (S304). If it has detected a lever operation toward the dump side (tilt side) (S304: Yes), the controller 100 aborts the process (S304). If it has not detected a lever operation toward the dump side (tilt side) (S304: No), the controller 100 ends Process 1 shown in FIG. 13.

[0064] On the one hand, in the process shown in FIG. 12, after starting Process 1 (FIG. 13) (S202), the controller 100 counts the time after the tilting hold operation is detected (S203). Next, the controller 100 determines whether a tilting hold operation to the tilt side (dump side) has been detected within a predetermined time (S204). If a tilting hold operation to the tilt side (dump side) has not been detected within the predetermined time (S204: No), the controller 100 clears the counter (S208) and ends the process shown in FIG. 12. If a tilting hold operation to the tilt side (dump side) has been detected within the predetermined time (S204: Yes), the controller 100 determines whether Process 1 is being executed (S205). If Process 1 is being executed (S205: Yes), the controller 100 aborts Process 1 (S206). If Process 1 is not being executed (S205: No), or if Process 1 has been aborted (S206), the controller 100 starts Process 2 (FIG. 14) (S207), clears the count (S208), and ends the process shown in FIG. 12.

[0065] In Process 2 shown in FIG. 14, the controller 100 first determines a target bucket angle at which the posture of the bucket 12 becomes the tilt end (dump end) state according to the current boom angle (S401). Next, the controller 100 outputs a command so that the current bucket angle becomes the target bucket angle (S402). Next, the controller 100 determines whether a lever operation to the dump side (tilt side) has been detected (S403). If a lever operation to the dump side (tilt side) has been detected (S403: Yes), the controller 100 aborts the process (S404). On the other hand, if a lever operation to the dump side (tilt side) has not been detected (S403: No), the controller 100 determines whether the grounding of the bucket 12 has been detected (S405). If the grounding of the bucket 12 has been detected (S405: Yes), the controller 100 aborts the process (S404). If the grounding of the bucket 12 has not been detected (S405: No), the controller 100 ends the process shown in FIG. 14.

[0066] Through the above processing, when the bucket 12 is in the second posture or a posture between the first and second postures, and when the dump side tilting hold operation is performed once, the controller 100 adjusts the bucket 12 to the first posture (horizontal posture). Also, when the bucket 12 is in the third posture or a posture between the first and third postures, and when the tilt side tilting hold operation is performed once, the controller 100 adjusts the bucket 12 to the first posture (horizontal posture).

[0067] When the bucket 12 is in an arbitrary posture, and when the tilt side tilting hold operation is continuously repeated within a predetermined time, the controller 100 adjusts the bucket 12 to the second posture (tilt end). Also, when the bucket 12 is in an arbitrary posture, and when the dump side tilting hold operation is continuously repeated within a predetermined time, the controller 100 adjusts the bucket 12 to the third posture (dump end).

[0068] (Function and Effect) As described above, according to the controller 100 according to the second embodiment, when the target bucket angle determination unit 107 of the controller 100 receives a command signal for operating the posture of the bucket 12, it controls the movable support unit 17 with the first posture as the target posture of the bucket 12. Also, when the controller 100 continuously receives a command signal indicating the current posture of the bucket 12 within a predetermined time, it selects a target posture different from the first posture among at least three types of target postures as the target posture of the bucket 12 and controls the movable support unit 17.

[0069] When the target bucket angle determination unit 107 continuously receives the first command signal from the operation signal detection unit 101 repeatedly within a predetermined time, it selects a second posture as the target posture from at least three types of target posture setting values stored in the storage unit 105 as the target posture of the bucket 12, and controls the movable support unit 17. Further, when the target bucket angle determination unit 107 continuously receives the second command signal from the operation signal detection unit 101 repeatedly within a predetermined time, it selects a third posture as the target posture from at least three types of target posture setting values stored in the storage unit 105 as the target posture of the bucket 12, and controls the movable support unit 17.

[0070] According to the present embodiment, by performing a predetermined tilting holding operation on the bucket operating device 33, the posture of the working tool can be automatically adjusted to a plurality of postures.

[0071] <Modification example or other embodiment of the present embodiment> As described above, the embodiments of the present invention have been described with reference to the drawings. However, the specific configuration is not limited to the above embodiments, and design changes and the like within the scope not departing from the gist of the present invention are also included.

[0072] For example, the wheel loader 1 may be remotely operable. In this case, a part or all of the controller 100 and the operating device 32 can be provided, for example, at a place where remote operation is performed.

[0073] Further, for example, the working machine (or work vehicle) is not limited to the wheel loader, and can be other working machines such as a hydraulic excavator including a working tool and a movable support unit for the working tool. Further, the working tool is not limited to the bucket. The working tool may be, for example, a fork, a bail grab, etc. that can be detachably attached to the wheel loader as an attachment.

[0074] Further, part or all of the program executed by the computer in the above embodiment can be distributed via a computer-readable recording medium or a communication line.

Description of reference numerals

[0075] 1 Wheel loader (working machine), 2 Vehicle body, 3 Cab, 4 Travel device, 5 Wheels, 6 Tires, 10 Working implement, 11 Boom, 12 Bucket (working tool), 12T Cutting edge, 13 Boom cylinder, 14 Bucket cylinder, 15 Bell crank, 16 Link, 17 Movable support part, 100 Controller

Claims

1. A control system for a working machine having a working machine including a working tool and a movable support portion that changes the posture of the working tool, comprising a controller including a storage unit that stores at least three types of target postures, wherein the controller, selects any one of the at least three types of target postures as the target posture of the working tool based on a command signal for operating the posture of the working tool and a detection signal indicating the current posture of the working tool, and controls the movable support portion, the at least three types of target postures include a first posture, a second posture, and a third posture, the command signal includes a first command signal and a second command signal, the working tool is rotatable in a first posture region and a second posture region, the first posture region is a posture region between the first posture and the second posture, the second posture region is a posture region between the first posture and the third posture, wherein the controller, when receiving the first command signal and the current posture of the working tool is in the second posture region, selects the first posture as the target posture, when receiving the second command signal and the current posture of the working tool is in the first posture region, selects the first posture as the target posture, a control system.

2. A control system for a working machine having a working machine including a working tool and a movable support portion that changes the posture of the working tool, comprising a controller including a storage unit that stores at least three types of target postures including a first posture, wherein the controller, when receiving a command signal for operating the posture of the working tool, controls the movable support portion with the first posture as the target posture of the working tool, when the command signal is continuously received repeatedly within a predetermined time, selects a target posture different from the first posture among the at least three types of target postures as the target posture of the working tool, and controls the movable support portion, the at least three types of target postures further include a second posture and a third posture, the command signal includes a first command signal and a second command signal, wherein the controller, when the first command signal is continuously received repeatedly within a predetermined time, determines the second posture as the target posture of the working tool, when the second command signal is continuously received repeatedly within a predetermined time, determines the third posture as the target posture of the working tool, a control system.

3. The first posture is the horizontal posture of the working tool, The second posture is the carrying posture of the working tool, The third posture is the soil discharging posture of the working tool or the grounding posture of the working tool The control system according to claim 1 or 2.

4. The working tool operating device that outputs the command signal is a lever operable between a first control position and a second control position, The first command signal is a signal output when the lever is operated to the first control position, The second command signal is a signal output when the lever is operated to the second control position, The control system according to claim 1 or 2.

5. The working tool operating device that outputs the command signal includes a lever operable between a first control position and a second control position and a switch, The first command signal is a signal output when the lever is operated in the direction of the first control position and the switch is operated, The second command signal is a signal output when the lever is operated in the direction of the second control position and the switch is operated, The control system according to claim 1 or 2.

6. The working tool operating device that outputs the command signal includes a first switch and a second switch, The first command signal is a signal output when the first switch is operated, The second command signal is a signal output when the second switch is operated, The control system according to claim 1 or 2.

7. A control method for a working machine having a working machine including a working tool and a movable support portion that changes the posture of the working tool, Storing at least three types of target postures, Selecting any one of the at least three types of target postures based on a command signal for operating the posture of the working tool and a detection signal indicating the current posture of the working tool, Controlling the movable support portion with the selected target posture as the target posture of the working tool, Comprising, The at least three types of target postures include a first posture, a second posture, and a third posture, The command signal includes a first command signal and a second command signal, The working tool is rotatable between a first posture region and a second posture region, The first posture region is a posture region between the first posture and the second posture, The second posture region is a posture region between the first posture and the third posture, In the step of selecting, when the first command signal is received and the current posture of the work tool is in the second posture region, the first posture is selected as the target posture, when the second command signal is received and the current posture of the work tool is in the first posture region, the first posture is selected as the target posture, Control method.

8. A control method for a working machine having a work tool and a movable support portion that changes the posture of the work tool, storing at least three types of target postures including a first posture; when a command signal for operating the posture of the work tool is received, selecting the first posture as the target posture; when the command signal is continuously received repeatedly within a predetermined time, selecting a target posture different from the first posture among the at least three types of target postures; controlling the movable support portion with the selected target posture as the target posture of the work tool; comprising: the at least three types of target postures further include a second posture and a third posture, the command signal includes a first command signal and a second command signal, In the step of selecting, when the first command signal is continuously received repeatedly within a predetermined time, determining the second posture as the target posture of the work tool; when the second command signal is continuously received repeatedly within a predetermined time, determining the third posture as the target posture of the work tool, Control method.

9. A working machine having a work tool and a movable support portion that changes the posture of the work tool, comprising a controller that controls the movable support portion, The controller, includes a storage unit that stores at least three types of target postures, selects any one of the at least three types of target postures based on a command signal for operating the posture of the work tool and a detection signal indicating the current posture of the work tool as the target posture of the work tool, and controls the movable support portion, the at least three types of target postures include a first posture, a second posture, and a third posture, the command signal includes a first command signal and a second command signal, the work tool is rotatable between a first posture region and a second posture region, the first posture region is a posture region between the first posture and the second posture, The second posture area is a posture area between the first posture and the third posture, The controller, when receiving the first command signal and the current posture of the working tool is in the second posture area, selects the first posture as the target posture, when receiving the second command signal and the current posture of the working tool is in the first posture area, selects the first posture as the target posture, working machine.

10. A working machine having a working tool and a movable support portion that changes the posture of the working tool, comprising a controller that controls the movable support portion, The controller, includes a storage unit that stores at least three types of target postures including a first posture, when receiving a command signal for operating the posture of the working tool, controls the movable support portion with the first posture as the target posture of the working tool, when the command signal is continuously received repeatedly within a predetermined time, selects a target posture different from the first posture among the at least three types of target postures as the target posture of the working tool, and controls the movable support portion, the at least three types of target postures further include a second posture and a third posture, the command signal includes a first command signal and a second command signal, The controller, when continuously receiving the first command signal repeatedly within a predetermined time, determines the second posture as the target posture of the working tool, when continuously receiving the second command signal repeatedly within a predetermined time, determines the third posture as the target posture of the working tool, working machine.

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