Work machine, work machine control system

Abstract

To provide a work machine that can be suppressed from operating differently from an operator's intention.SOLUTION: A bulldozer comprises a traveling operation lever that accepts an operator's operation and outputs a traveling command to enable or stop a traveling device, a fuel adjustment dial that sets the engine speed, a seating sensor that outputs a seating signal indicating the detection result of whether the operator is seated on an operator seat, a monitor that provides a notification to the operator, and a controller. The controller causes the monitor to provide a notification when there is a traveling command from the traveling operation lever that the traveling device is ready to travel, the set value of the engine speed is a predetermined value or less, and the operator is not seated in the operator seat.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to work machines and control systems for work machines. [Background technology]

[0002] Japanese Patent Laid-Open Publication No. 2005-233420 (Patent Document 1) discloses a hydrostatic transmission vehicle that runs by converting engine output through a hydrostatic transmission. The hydrostatic transmission includes a variable displacement pump driven by the engine, and a variable displacement hydraulic motor that receives pressurized oil from the variable displacement pump and rotates. By changing the swash plate angle of the variable displacement pump or the variable displacement hydraulic motor, the capacity of the hydrostatic transmission can be changed, and the engine output that the hydrostatic transmission can absorb can be changed, or the vehicle speed of the work vehicle can be changed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2005-233420 A Summary of the Invention [Problem to be solved by the invention]

[0004] It is desirable to prevent a work machine from starting to move against the operator's intention while the machine is stopped.

[0005] The present disclosure proposes a work machine and a control system for the work machine that are capable of suppressing operations contrary to the operator's intentions. [Means for solving the problem]

[0006] According to an aspect of the present disclosure, a work machine is proposed. The work machine includes a vehicle body, an engine installed in the vehicle body, a traveling device attached to the vehicle body and traveling by the output of the engine, a traveling operation device that receives an operation from an operator and outputs a traveling command to enable or stop the traveling device, a rotation speed setting device that sets the engine rotation speed, a seating sensor that outputs a seating signal indicating a detection result of whether the operator is seated in the operator seat, an alarm device that issues an alarm to the operator, and a controller. The controller receives an input of a traveling command from the traveling operation device, an input of a set value of the engine rotation speed from the rotation speed setting device, and an input of a seating signal from the seating sensor. The controller causes the alarm device to execute an alarm when there is a traveling command that enables the traveling device to travel, the set value of the engine rotation speed is equal to or less than a predetermined value, and the operator is not seated in the operator seat.

[0007] According to an aspect of the present disclosure, a work machine is proposed. The work machine includes a vehicle body, an engine installed in the vehicle body, a traveling device attached to the vehicle body and traveling by the output of the engine, a traveling operation device that receives an operation from an operator and outputs a traveling command to enable or stop the traveling device, a rotation speed setting device that sets the engine rotation speed, a seating sensor that outputs a seating signal indicating a detection result of whether the operator is seated in the operator seat, and a controller. The controller receives an input of a traveling command from the traveling operation device, an input of a set value of the engine rotation speed from the rotation speed setting device, and an input of a seating signal from the seating sensor. The controller disables the traveling device when there is a traveling command to enable the traveling device, the set value of the engine rotation speed is equal to or less than a predetermined value, and the operator is not seated in the operator seat. Effect of the Invention

[0008] According to the work machine according to the present disclosure, it is possible to prevent the work machine from performing operations contrary to the operator's intentions. [Brief description of the drawings]

[0009] [Figure 1] 1 is a schematic side view of a bulldozer as an example of a work machine based on an embodiment. [Diagram 2] FIG. 2 is a plan view showing a schematic configuration of a part of the interior of the cab shown in FIG. [Diagram 3] 1 is a circuit diagram showing a system configuration of a bulldozer according to an embodiment. [Figure 4] 4 is a flowchart showing an example of a bulldozer control method. [Diagram 5] FIG. 4 is a schematic diagram showing an example of a display on a monitor. [Figure 6] 10 is a flowchart showing a control method for a bulldozer according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment will be described with reference to the drawings. In the following description, the same components are denoted by the same reference numerals. The names and functions of the components are also the same. Therefore, detailed description thereof will not be repeated.

[0011] [First embodiment] <Work machine configuration> In the embodiment, a bulldozer 10 will be described as an example of a work machine. Fig. 1 is a schematic side view of a bulldozer 10 as an example of a work machine based on the embodiment.

[0012] As shown in FIG. 1, a bulldozer 10 mainly comprises a vehicle body 11, a blade 12 as a working machine, and a traveling device 13.

[0013] The vehicle body 11 has a cab (operator's compartment) 18 and an engine room 19. The cab 18 is disposed at the upper rear part of the vehicle body 11. An operator who operates the bulldozer 10 rides in the cab 18. The cab 18 has an operator's seat (driver's seat) inside for the operator to sit in. The engine room 19 is disposed in front of the cab 18. The engine room 19 is disposed between the cab 18 and the blade 12. An engine 21, which is a power source of the bulldozer 10, such as an internal combustion engine, is disposed in the engine room 19.

[0014] In the embodiment, the direction in which the bulldozer 10 travels straight ahead is referred to as the fore-aft direction of the bulldozer 10. In the fore-aft direction of the bulldozer 10, the side where the blade 12 protrudes from the vehicle body 11 is referred to as the front direction. In the fore-aft direction of the bulldozer 10, the side opposite the front direction is referred to as the rear direction. The left-right direction of the bulldozer 10 is a direction perpendicular to the fore-aft direction in a plan view. Looking forward, the right and left sides in the left-right direction are the right direction and the left direction, respectively. The up-down direction of the bulldozer 10 is a direction perpendicular to a plane defined by the fore-aft direction and the left-right direction. In the up-down direction, the side with the ground is the lower side, and the side with the sky is the upper side.

[0015] The blade 12 is a working machine for performing work such as excavating and leveling the ground surface. The blade 12 is disposed in front of the vehicle body 11 with a gap between it and the vehicle body 11. The blade 12 has a cutting edge at its lower edge that comes into contact with the ground during work. The blade 12 is supported on both the left and right sides by frames 14. The blade 12 is supported by the vehicle body 11 via the frames 14.

[0016] The frame 14 is a rectangular prism-shaped member. The front end of the frame 14 is attached to the rear surface of the blade 12 by a rotatable support. The rear end of the frame 14 is supported by the vehicle body 11 so as to be rotatable.

[0017] The blade 12 is driven by a tilt cylinder 15 and a lift cylinder 16. The tilt cylinder 15 and the lift cylinder 16 are hydraulic cylinders.

[0018] The front end of the tilt cylinder 15 is rotatably supported on the back surface of the blade 12. The rear end of the tilt cylinder 15 is rotatably supported on the upper surface of the frame 14. The tilt cylinder 15 is connected to the frame 14 and the blade 12. The hydraulic expansion and contraction of the tilt cylinder 15 causes the upper edge of the blade 12 to move back and forth, causing the blade 12 to tilt (tilt).

[0019] The front end of the lift cylinder 16 is rotatably attached to the upper surface of the frame 14. The rear end of the lift cylinder 16 is rotatably supported on the side of the vehicle body 11. The blade 12 moves up and down (lifts) as the lift cylinder 16 expands and contracts due to hydraulic pressure.

[0020] The vehicle body 11 is supported by a traveling device 13 so as to be capable of traveling. The traveling device 13 has a pair of track-type traveling bodies separated in the left-right direction. The vehicle body 11 is disposed between the pair of left and right track-type traveling bodies. Each of the left and right track-type traveling bodies has a driving wheel (sprocket) 13a, an idler wheel (idler) 13b, a crawler 13c, and a track frame 13d.

[0021] The driving wheel 13a and the track frame 13d are attached to the side of the vehicle body 11. The driving wheel 13a is arranged to be rotatably driven at the rear of the track frame 13d. An idler wheel 13b is attached to the track frame 13d. The idler wheel 13b is rotatably arranged, for example, at the front end of the track frame 13d.

[0022] The crawler belt 13c is configured in an annular (endless) shape and is wound around the drive wheel 13a and the idler wheel 13b. The crawler belt 13c is meshed with the drive wheel 13a and configured to be rotatable by the rotational drive of the drive wheel 13a. By the rotation of the crawler belt 13c, the idler wheel 13b is meshed with the crawler belt 13c and can be rotated by the rotation.

[0023] A hydraulic motor 23 included in an HST (Hydraulic Static Transmission) circuit is connected to the drive wheels 13a. A hydraulic pump 22 included in the HST circuit is disposed in the engine compartment 19. A charge pump 24 that supplies hydraulic oil to the parking brake circuit is disposed in the engine compartment 19.

[0024] Fig. 2 is a plan view showing a schematic partial configuration inside the cab 18 shown in Fig. 1. As shown in Fig. 2, an operator seat 31 for an operator to sit on to operate the bulldozer 10 is arranged inside the cab 18. The operator seat 31 is arranged approximately in the vicinity of the center of the cab 18.

[0025] A console 32 is disposed to the left of the operator seat 31 in the cab 18. The console 32 is provided with a travel operation lever 33 for operating the bulldozer 10 to travel, a parking brake switch 34 for operating the parking brake that keeps the traveling device 13 in a stopped state, a fuel adjustment dial 35 for setting the rotation speed of the engine 21, and the like. An operator seated on the operator seat 31 can operate the travel operation lever 33, the parking brake switch 34, and the fuel adjustment dial 35 with his left hand. A console (not shown) is also disposed to the right of the operator seat 31, and on that console, for example, an operation lever for operating the blade 12 is provided.

[0026] A monitor 36 is disposed in front of the operator seat 31 in the cab 18. The monitor 36 corresponds to the notification device in the embodiment, which displays information and notifies the operator. A deceleration / brake pedal 37 for adjusting the vehicle speed of the bulldozer 10 is also disposed in front of the operator seat 31. The operator seated in the operator seat 31 can reduce the travel speed of the bulldozer 10 by stepping on the deceleration / brake pedal 37 with his / her foot.

[0027] <System configuration> Fig. 3 is a circuit diagram showing a system configuration of the bulldozer 10 of the embodiment. The controller 40 shown in Fig. 3 controls the operation of the bulldozer 10. The controller 40 may be mounted on the bulldozer 10, so that the bulldozer 10 is equipped with the controller 40. The controller 40 may not be mounted on the bulldozer 10, but may be disposed outside the bulldozer 10. A control system for the bulldozer 10 may be configured in which the external controller 40 controls the bulldozer 10. The external controller 40 may be disposed at the work site of the bulldozer 10, or may be disposed at a remote location away from the work site of the bulldozer 10.

[0028] A battery 41 is connected to the controller 40. The battery 41 is a power source for the controller 40, and power is supplied from the battery 41 to the controller 40. A battery disconnect switch 42 is provided in a circuit connecting the battery 41 and the controller 40. The battery disconnect switch 42 is provided to cut off the power supply from the battery 41 to the controller 40 during maintenance, when the bulldozer 10 is parked for an extended period of time, etc.

[0029] The bulldozer 10 is equipped with a power transmission device that transmits the power generated by the engine 21 to the drive wheels 13a. The power transmission device has an HST circuit that transmits power hydraulically. The HST circuit includes a hydraulic pump 22, a hydraulic motor 23, and a closed hydraulic circuit (closed circuit) that connects the hydraulic pump 22 and the hydraulic motor 23.

[0030] The hydraulic pump 22 is a variable displacement hydraulic pump. A drive shaft of the hydraulic pump 22 is connected to the output shaft of the engine 21, and rotates by the drive of the engine 21. The hydraulic pump 22 pressurizes and discharges oil in the HST circuit. The hydraulic pump 22 converts the drive force of the engine 21 into oil (fluid) energy. This oil energy is transmitted to the hydraulic motor 23.

[0031] The hydraulic motor 23 is a variable displacement hydraulic motor. The drive shaft of the hydraulic motor 23 is connected to the input shaft of the drive wheel 13a. High-pressure oil supplied by the hydraulic pump 22 is transmitted to the hydraulic motor 23 via a closed circuit connecting the hydraulic pump 22 and the hydraulic motor 23, thereby rotating the drive shaft of the hydraulic motor 23. The rotation of the drive shaft of the hydraulic motor 23 is transmitted to the drive wheel 13a, causing the drive wheel 13a to rotate. In this way, the hydraulic motor 23 converts the energy of the input oil into rotational energy (driving energy) and outputs the driving energy to the drive wheel 13a of the traveling device 13.

[0032] The power transmission device may be configured to transmit power hydraulically, or may include any combination of a transmission, an electric motor, and the like.

[0033] The charge pump 24 is a fixed displacement hydraulic pump. The charge pump 24 is connected to the engine 21. The charge pump 24 is driven by the engine 21 to supply hydraulic oil to the parking brake circuit.

[0034] The travel operation lever 33 is operated by the operator to set the traveling device 13 to any one of a forward state, a reverse state, and a neutral state. In Fig. 3, the travel operation lever 33 in the neutral position is indicated by a solid line and labeled with the reference symbol 33N, the travel operation lever 33 in the forward position is indicated by a dashed line and labeled with the reference symbol 33F, and the travel operation lever 33 in the reverse position is indicated by a dashed line and labeled with the reference symbol 33R.

[0035] 3, the travel control lever 33 can be moved from a neutral position to a forward position and a reverse position. The operator can operate the travel control lever 33 in a plurality of directions, including one direction from the neutral position to the forward position (e.g., forward) and another direction from the neutral position to the reverse position (e.g., reverse).

[0036] The travel operation lever 33 has a detent mechanism that holds the lever in a forward position or a reverse position, which is a position where the lever is tilted from the neutral position. Even if the operator releases his / her hand after operating the travel operation lever 33, the travel operation lever 33 is held in the neutral position, forward position, or reverse position. When the travel operation lever 33 is held in the forward position, the travel device 13 is in a forward state where forward travel is possible. When the travel operation lever 33 is held in the reverse position, the travel device 13 is in a reverse state where reverse travel is possible. When the travel operation lever 33 is held in the neutral position, the travel device 13 is in a neutral state where travel is impossible and the travel device is stopped.

[0037] The travel operation lever 33 detects whether the travel operation lever 33 is in the neutral position, the forward position, or the reverse position, and outputs the detection result to the controller 40. The travel operation lever 33 corresponds to the travel operation device in the embodiment, which receives the operation of the operator and outputs a travel command to enable or stop the travel device 13.

[0038] The parking brake switch 34 corresponds to a brake operation device in the embodiment for operating the activation and release of a parking brake that keeps the traveling device 13 in a stopped state. The parking brake switch 34 is, for example, a toggle switch. The parking brake switch 34 has internal switches 62 and 63. When the operator operates the parking brake switch 34 in one direction, the internal switch 62 is turned on and the internal switch 63 is turned off. When the operator operates the parking brake switch 34 in the other direction, the internal switch 62 is turned off and the internal switch 63 is turned on.

[0039] The internal switches 62, 63 output whether they are on or off to the controller 40. As a result, an operation signal of the parking brake switch 34 is input to the controller 40.

[0040] An operator switches the parking brake between an applied state and a released state by operating the parking brake switch 34. For example, the parking brake may be applied when the internal switch 62 is turned off and the internal switch 63 is turned on, and the parking brake may be released when the internal switch 62 is turned on and the internal switch 63 is turned off.

[0041] The fuel adjustment dial 35 corresponds to a rotation speed setting device in the embodiment, which sets the rotation speed of the engine 21 by setting the amount of fuel supplied to the engine 21. The amount of operation of the fuel adjustment dial 35 by the operator is converted into an electric signal and input to the engine controller 50. The engine controller 50 controls the rotation speed of the engine 21 by supplying an appropriate amount of fuel according to the conditions to the engine 21. The engine controller 50 is electrically connected to the controller 40, and is capable of receiving an input of a control signal from the controller 40 and outputting a control setting value of the engine controller 50 to the controller 40.

[0042] The display contents of the monitor 36 are controlled by the controller 40. In response to commands from the controller 40 to the monitor 36, the monitor 36 displays vehicle body information and pop-up displays, which will be described later.

[0043] The deceleration / brake pedal 37 can select from two pedal modes: a deceleration mode in which the traveling speed of the bulldozer 10 decreases and the rotation speed of the engine 21 decreases when the pedal is depressed, and a brake mode in which the traveling speed of the bulldozer 10 decreases but the rotation speed of the engine 21 does not decrease when the pedal is depressed. A potentiometer 69 is attached to the rotating shaft of the deceleration / brake pedal 37. The potentiometer 69 detects the amount of depression of the deceleration / brake pedal 37 by the operator by detecting the rotation angle of the deceleration / brake pedal 37 around the rotating shaft. The potentiometer 69 outputs the detection result to the controller 40.

[0044] The parking brake 52 is provided on the drive shaft of the hydraulic motor 23. The parking brake 52 has a disc brake portion and a piston portion. The parking brake 52 is configured such that the multiple discs of the disc brake portion come into contact with each other due to the biasing force of an elastic member provided in the piston portion, thereby releasing the parking brake 52 and allowing the traveling device 13 to move. When hydraulic oil is supplied to the piston portion, the piston portion, which operates hydraulically, causes the multiple discs of the disc brake portion to come out of contact with each other. This causes the parking brake 52 to operate and the traveling device 13 to become immovable. When hydraulic oil is discharged from the piston portion, the parking brake 52 is released by the biasing force of the elastic member, allowing the traveling device 13 to move.

[0045] The rotation speed sensor 53 detects the rotation speed of the drive shaft between the parking brake 52 and the drive wheels 13 a, and outputs the detection result to the controller 40.

[0046] The parking brake circuit is an oil flow path that connects the charge pump 24 and the parking brake 52. The parking brake 52 is provided with parking brake solenoid valves 55, 56 and a towed valve 57. The parking brake solenoid valve 55 is connected to the deceleration / brake pedal 37 and the parking brake switch 34 via a limit switch 70. The parking brake solenoid valve 55 is switched between an excited state and a de-excited state by the operation of the parking brake switch 34 and the deceleration / brake pedal 37.

[0047] The parking brake solenoid valve 56 is switched between an excited state and a de-excited state in accordance with a control signal input from the controller 40. The towed valve 57 is normally kept open, and is operated to a closed state when the parking brake 52 is manually released in an emergency such as a failure of the engine 21. A pressure sensor 59 for detecting the pressure of hydraulic oil is provided in the parking brake circuit between the towed valve 57 and the parking brake 52. The pressure sensor 59 outputs the detection result of the hydraulic oil pressure to the controller 40.

[0048] The operator seat 31 is provided with a seating sensor 61. When the operator sits on the operator seat 31, the seating sensor 61 is pressed down, and the voltage output value from the seating sensor 61 to the controller 40 is changed. The seating sensor 61 outputs a seating signal indicating the detection result as to whether or not the operator is seated on the operator seat 31 to the controller 40.

[0049] <How to control Bulldozer 10> An example of a method for controlling the bulldozer 10 of the embodiment having the above-mentioned configuration will be described below. FIG 4 is a flowchart showing an example of the method for controlling the bulldozer 10.

[0050] 4, in step S1, the controller 40 receives a travel command input from the travel operation lever 33 (travel operation device). When the operator operates the travel operation lever 33 to the forward or reverse position, the travel operation lever 33 outputs a travel command to the controller 40 that enables the travel device 13 to travel. When the operator operates the travel operation lever 33 to the neutral position, the travel operation lever 33 outputs a travel command to the controller 40 to stop the travel device 13.

[0051] In step S2, the controller 40 receives an input of a set value of the rotation speed of the engine 21 from the fuel adjustment dial 35 (rotation speed setting device). The fuel adjustment dial 35 stores a set value of the rotation speed of the engine 21 according to the amount of operation of the fuel adjustment dial 35 by the operator. The set value of the rotation speed of the engine 21 according to the operation of the operator is input from the fuel adjustment dial 35 to the engine controller 50. The set value of the rotation speed of the engine 21 is transmitted from the engine controller 50 to the controller 40.

[0052] The set value of the rotation speed of the engine 21 according to the operation amount of the fuel adjustment dial 35 may be stored in the engine controller 50 or the controller 40. In this case, the operation amount of the fuel adjustment dial 35 is input from the fuel adjustment dial 35 to the engine controller 50, and the set value of the rotation speed of the engine 21 is calculated in the engine controller 50 or the controller 40.

[0053] In step S3, the controller 40 receives an input of a seating signal from the seating sensor 61 indicating the detection result as to whether the operator is seated on the operator seat 31 or not.

[0054] In step S4, the controller 40 judges whether the traveling device 13 is capable of traveling. In step S1, if a traveling command to enable the traveling device 13 to travel is input from the traveling operation lever 33, the controller 40 judges that the traveling device 13 is capable of traveling. If a traveling command to stop the traveling device 13 is input from the traveling operation lever 33, the controller 40 judges that the traveling device 13 is not capable of traveling.

[0055] In step S5, the controller 40 judges whether or not the set value of the rotation speed of the engine 21 is equal to or less than a predetermined value. A threshold value related to the rotation speed of the engine 21 is stored in the controller 40. The controller 40 compares the set value of the rotation speed of the engine 21 input in step S2 with this threshold value (predetermined value).

[0056] In step S6, the controller 40 determines whether or not the operator is seated in the operator seat 31 based on the seating signal input in step S3.

[0057] If there is a command to enable the traveling device 13 to travel (YES in step S4), the set value of the RPM of the engine 21 is equal to or lower than a predetermined value (YES in step S5), and the operator is not seated in the operator seat 31 (NO in step S6), the process proceeds to step S7. The controller 40 outputs a control signal to the monitor 36 (notification device) to display information to be notified to the operator. In this way, the controller 40 notifies the operator, who is viewing the monitor 36, of the next operation to be performed, etc.

[0058] Fig. 5 is a schematic diagram showing an example of the display on the monitor 36. By the process in step S7, the monitor 36 pops up and displays a window 80 shown in Fig. 5. The window 80 is displayed so as to overlap the vehicle body information and the like displayed on the monitor 36. The window 80 includes a title display 81, a pictorial display 82, and a main text display 83.

[0059] 5, the title display 81 displays the result of detecting the current situation, "Absence detected with travel lever other than N." In other words, the display shows a situation in which the operator is not seated in the operator seat 31 with the travel control lever 33 in a forward or reverse position other than the neutral position.

[0060] The pictorial display 82 displays the current situation in a picture, thereby enabling the operator who sees the pictorial display 82 to easily understand the current situation. As shown in Fig. 5, a simple display is provided to indicate that the operator is not seated in the operator seat 31.

[0061] The main text display 83 includes a text message that specifically notifies the operator of the operation to be performed. Specifically, the main text display 83 includes an indication that "please put the travel lever in N position" to encourage the operator to operate the travel operation lever 33 in the neutral position. The main text display 83 includes an indication that encourages the operator to operate the travel operation lever 33 so as to output a stop of the travel device 13. The main text display 83 also includes a text message that encourages the operator to take a seat in the operator seat 31, that is, "take a seat."

[0062] 5 indicates that the notification by the monitor 36 (notification device) is accompanied by the generation of sound. The warning sound 90 is, for example, an intermittent sound.

[0063] Returning to Fig. 4, in step S8, controller 40 determines whether or not the operator has moved travel operation lever 33 to the neutral position in accordance with the display on monitor 36. Controller 40 determines whether or not a travel command to stop the travel device 13 has been input from travel operation lever 33, thereby determining whether travel operation lever 33 remains in the forward or reverse position, or whether travel operation lever 33 has moved to the neutral position. If it is determined that travel operation lever 33 is not in the neutral position (NO in step S8), the determination is repeated.

[0064] If it is determined that the travel operation lever 33 is in the neutral position (YES in step S8), the process proceeds to step S9, where notification to the operator is stopped. Specifically, the pop-up display of window 80 disappears from the monitor 36, and the display returns to the original screen. Then, the process ends ("End" in FIG. 4).

[0065] If it is determined in step S4 that there is no command to enable the traveling device 13 to travel (NO in step S4), if it is determined in step S5 that the set value of the rotation speed of the engine 21 exceeds a predetermined value (NO in step S5), or if it is determined that the operator is seated in the operator seat 31 (YES in step S6), steps S7 to S9 are skipped and the process ends ("End" in FIG. 4).

[0066] If there is no command to enable the traveling device 13 to travel, the traveling device 13 will not travel, and so there is no need for a notification. If there is a command to enable the traveling device 13 to travel and the RPM of the engine 21 is above a predetermined value, the traveling device 13 is in a traveling state, and the operator will not leave the seat while traveling, so there is no need for a notification. The operator who remains seated in the operator seat 31 is aware of the current situation, so there is no need for a notification. Therefore, no notification is made to the operator.

[0067] <Action and Effects> Although some of the description herein overlaps with the above description, the characteristic configuration and effects of this embodiment can be summarized as follows.

[0068] The bulldozer 10 of the embodiment includes a monitor 36 as shown in Figs. 2 and 3. As shown in Fig. 5, the monitor 36 notifies the operator. As shown in Fig. 3, the bulldozer 10 includes a controller 40. The controller 40 receives a travel command for enabling or stopping the traveling device 13 from the travel operation lever 33. The controller 40 receives a set value of the engine speed from the fuel adjustment dial 35. The controller 40 receives a seating signal from the seat sensor 61 indicating the detection result of whether the operator is seated in the operator seat 31. As shown in Fig. 4, the controller 40 causes the monitor 36 to execute a notification when there is a travel command for enabling the traveling device 13 to travel, the set value of the engine speed is equal to or less than a predetermined value, and the operator is not seated in the operator seat 31.

[0069] The bulldozer 10 equipped with an HST circuit as a power transmission device can be stopped by operating the fuel adjustment dial 35 to set the engine 21 speed below a predetermined value, for example to the minimum speed, even if the travel control lever 33 is in the forward or reverse position. While the bulldozer 10 is stopped, there is a possibility that the operator may accidentally dismount. If another operator who gets on the bulldozer 10 next operates the fuel adjustment dial 35 to increase the engine 21 speed without knowing that the travel control lever 33 is in the forward or reverse position, the bulldozer 10 will start traveling against the operator's intention.

[0070] In the bulldozer 10 of the embodiment, when the operator stands up from the operator seat 31 to get off, it is detected that the operator is not seated, and a window 80 for notifying the operator of information is displayed on the monitor 36. The next operator can recognize the current situation and the actions that should be taken in the current situation by looking at the window 80 displayed on the monitor 36. By acting according to the display of the window 80, even if the fuel adjustment dial 35 is subsequently operated to increase the RPM of the engine 21, the bulldozer 10 will not start traveling at that point. This makes it possible to prevent the bulldozer 10 from starting to travel against the operator's will.

[0071] 5, the information presented to the operator by the monitor 36 includes a display urging the operator to operate the travel operation lever 33 so as to output a stop of the traveling gear 13, specifically, a display urging the operator to place the travel operation lever 33 in the neutral position. By placing the travel operation lever 33 in the neutral position in accordance with the display in the window 80 displayed on the monitor 36, it is possible to prevent the bulldozer 10 from starting to travel against the operator's will.

[0072] 4, when the controller 40 receives a travel command input from the travel operation lever 33 to stop the traveling device 13, it stops the notification. After the travel operation lever 33 is placed in the neutral position to prevent the bulldozer 10 from traveling against the operator's will, the window 80 is turned off and the normal display screen is displayed on the monitor 36, allowing the operator to start work smoothly.

[0073] 5, the information presented to the operator by the monitor 36 includes a display encouraging the operator to sit in the operator seat 31. By having the operator comply with the obligation to wear a seat belt while in the cab 18 of the bulldozer 10, the operator can smoothly carry out work using the bulldozer 10.

[0074] 5, the notification of information to the operator by the monitor 36 includes displaying a text message. The operator can reliably recognize the operation to be performed by reading the text message in the main text display 83.

[0075] 5, the notification of information to the operator by the monitor 36 includes the generation of a sound. By generating a sound such as a warning sound 90 on the monitor 36 or another sound source, the operator can be motivated to check the display on the monitor 36, and the operator can be sure to recognize the content of the notification displayed on the monitor 36.

[0076] 2 and 3, the bulldozer 10 is provided with a parking brake switch 34 that operates to apply and release the parking brake 52. The controller 40 notifies the operator of information via the monitor 36 while the parking brake 52 is released. The controller 40 does not notify the operator of information via the monitor 36 while the parking brake 52 is applied. Since the traveling gear 13 does not travel while the parking brake 52 is applied, there is no need for notification. This makes it possible to simplify the control.

[0077] In the case of a conventional configuration having a parking brake lever as a brake operating device for operating the activation and release of the parking brake 52, the parking brake lever arranged in the path of the operator obstructs passage, making it possible to make the operator who is about to dismount realize that he is making a wrong movement. In the case of a configuration having the parking brake switch 34 instead of the parking brake lever, there is a possibility that the operator will mistakenly dismount without activating the parking brake 52 while the bulldozer 10 is stopped, but by displaying information that should be notified to the operator on the monitor 36, it is possible to more reliably prevent the bulldozer 10 from starting to travel against the operator's will.

[0078] As shown in FIG. 3, the power transmission device that transmits the driving force of the engine 21 to the traveling device 13 has a hydraulic pump 22, a hydraulic motor 23, and a closed circuit that connects the hydraulic pump 22 and the hydraulic motor 23. In the case where the power transmission device is configured to have a torque converter, if there is a travel command that the traveling device 13 is ready to travel, the bulldozer 10 continues to travel even if the rotation speed of the engine 21 is set to the minimum. Since the operator does not leave the seat during travel, there is no need to notify. In the case where the bulldozer 10 is configured to have an HST circuit, if there is a travel command that the traveling device 13 is ready to travel, the pump volume is controlled to zero and the bulldozer 10 stops if the set value of the rotation speed of the engine 21 is equal to or lower than a predetermined value. There is a possibility that the operator will mistakenly get off the bulldozer 10 while the bulldozer 10 is stopped, but by displaying information that should be notified to the operator on the monitor 36, it is possible to more reliably prevent the bulldozer 10 from starting to travel against the operator's will.

[0079] As shown in FIG. 1, by applying the configuration of the embodiment to a bulldozer 10 that is equipped with a blade 12 at the front of a body 11 and that performs work while traveling, it is possible to more reliably prevent the bulldozer 10 from starting to travel against the operator's will.

[0080] In the above embodiment, an example of a notification to an operator by the monitor 36 has been described. The notification to an operator who is about to get off the vehicle and the notification to the next operator who has boarded the vehicle may be different from each other. For example, the notification shown in FIG. 5 may be given to the next operator who has boarded the vehicle. On the other hand, a text message may be displayed to an operator who is about to get off the vehicle, encouraging them to get off after carrying out appropriate stopping procedures, such as putting the travel operation lever 33 into the neutral position and activating the parking brake 52, before getting off the vehicle.

[0081] In the above embodiment, an example has been described in which the window 80 is displayed as a pop-up on the monitor 36. The notification to the operator is not limited to a pop-up display. For example, the notification may be displayed on the monitor 36 in another display format, such as a scroll display. Instead of or in addition to the display on the monitor 36, the notification may be made by voice.

[0082] [Second embodiment] Fig. 6 is a flowchart showing a control method for the bulldozer 10 of the second embodiment. The processes from step S1 to step S6 shown in the flowchart of Fig. 6 are the same as those in Fig. 4. In the second embodiment, when there is a travel command to enable the traveling gear 13 to travel (YES in step S4), the set value of the rotation speed of the engine 21 is equal to or lower than a predetermined value (YES in step S5), and the operator is not seated in the operator seat 31 (NO in step S6), the process proceeds to step S17. In step S17, the controller 40 disables the traveling gear 13 from traveling.

[0083] In the bulldozer 10 of the second embodiment, when the operator stands up from the operator seat 31 to get off, it is detected that the operator is not seated, and the traveling gear 13 is disabled from traveling. For example, the controller 40 can disable the traveling gear 13 by controlling the parking brake solenoid valves 55, 56 to activate the parking brake 52. In this way, even if the next operator operates the fuel adjustment dial 35 to increase the rotation speed of the engine 21, the traveling gear 13 is disabled and the bulldozer 10 will not start traveling at that point. This makes it possible to prevent the bulldozer 10 from starting to travel against the operator's will.

[0084] In the above description of the embodiment, an example has been described in which the rotation speed of the engine 21 is set by the operator manually operating the fuel adjustment dial 35. In a configuration equipped with an automatic deceleration device that reduces the rotation speed of the engine 21 when there is no operation from the operator, the rotation speed of the engine 21 may drop to a predetermined value or lower due to the operation of the automatic deceleration device. Even in this case, the controller 40 causes the monitor 36 to issue an alert when there is a travel command indicating that the traveling gear 13 is ready to travel and the operator is not seated in the operator seat 31, thereby reliably preventing the bulldozer 10 from starting to travel against the operator's will.

[0085] In the above description of the embodiments, an example has been described in which the bulldozer 10 is equipped with the cab 18, and whether or not the operator is seated in the operator seat 31 in the cab 18 is detected by the seat sensor 61. The cab 18 does not necessarily have to be in the vehicle body 11. Even in the case of an unmanned bulldozer that does not have a cab and is remotely operated, there is still a possibility that the operator will leave the operator seat while the bulldozer is stopped, and therefore, by applying the configuration of the embodiment, it is possible to reliably prevent the bulldozer from starting to travel against the operator's will.

[0086] The embodiments disclosed herein are illustrative in all respects and should not be considered as limiting. The scope of the present invention is defined by the claims, not the above description, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0087] 10 bulldozer, 11 body, 12 blade, 13 traveling gear, 13a drive wheel, 18 cab, 19 engine compartment, 21 engine, 22 hydraulic pump, 23 hydraulic motor, 24 charge pump, 31 operator seat, 32 console, 33 travel control lever, 34 parking brake switch, 35 fuel adjustment dial, 36 monitor, 37 deceleration / brake pedal, 40 controller, 41 battery, 42 battery disconnect switch, 50 engine controller, 52 parking brake, 53 RPM sensor, 55, 56 parking brake solenoid valve, 57 towed valve, 59 pressure sensor, 61 seating sensor, 62, 63 internal switch, 69 potentiometer, 70 limit switch, 80 window, 81 title display, 82 pictorial display, 83 text display, 90 warning sound.

Claims

1. The car body and An engine installed in the vehicle body; a traveling device attached to the vehicle body and traveling using the output of the engine; A travel operation device that receives an operation from an operator and outputs a travel command to enable or stop the travel device; A rotation speed setting device for setting the rotation speed of the engine; a seating sensor that outputs a seating signal indicating a detection result of whether or not an operator is seated on the operator seat; a notification device for notifying an operator; and a controller. the rotation speed setting device sets an engine rotation speed to a predetermined value or less at which the vehicle body can be stopped, thereby making it possible to stop the traveling device even if the traveling operation device outputs a traveling command for enabling the traveling device to travel, The controller: receiving an input of the travel command from the travel operation device, receiving an input of a set value of the engine speed from the speed setting device, and receiving an input of the seating signal from the seating sensor; causing the notification device to issue a notification when there is a travel command indicating that the travel device is capable of traveling, a set value of the engine speed is equal to or less than a predetermined value at which the vehicle body can be stopped, and an operator is not seated in the operator seat. Working machinery.

2. The work machine according to claim 1 , wherein the notification by the notification device includes a display that prompts the operator to operate the traveling operation device so as to output a stop of the traveling device.

3. The traveling operation device includes an operation lever that can be operated in a plurality of directions, The work machine according to claim 2 , wherein the notification by the notification device includes a display urging the operator to place the operating lever in a neutral position.

4. The work machine according to claim 2 or 3, wherein the controller stops the notification by the notification device when the controller receives, from the travel operation device, the travel command to stop the travel device.

5. The work machine according to claim 1 , wherein the notification by the notification device includes a display encouraging an operator to take a seat in the operator seat.

6. The work machine according to claim 1 , wherein the notification by the notification device includes displaying a text message.

7. The work machine according to claim 6 , wherein the notification by the notification device is accompanied by the emission of a sound.

8. A brake operation device is provided for operating and releasing a parking brake for keeping the traveling device in a stopped state, The work machine according to claim 1 , wherein the controller issues an alert by the alert device while the parking brake is released.

9. The work machine according to claim 8 , wherein the brake operation device is a switch that can be operated by an operator seated on the operator seat.

10. a power transmission device that transmits the driving force of the engine to the traveling device, 10. The work machine according to claim 1, wherein the power transmission device includes: a pump that converts a driving force of the engine into fluid energy; and a motor that converts the energy of the fluid converted by the pump into driving energy and outputs the driving energy to the traveling device.

11. The work machine according to any one of claims 1 to 10, which is a bulldozer equipped with a blade at the front of the vehicle body.

12. The car body and An engine installed in the vehicle body; a traveling device attached to the vehicle body and traveling using the output of the engine; A travel operation device that receives an operation from an operator and outputs a travel command to enable or stop the travel device; A rotation speed setting device for setting the rotation speed of the engine; a seating sensor that outputs a seating signal indicating a detection result of whether or not an operator is seated on the operator seat; and a controller. the rotation speed setting device sets an engine rotation speed to a predetermined value or less at which the vehicle body can be stopped, thereby making it possible to stop the traveling device even if the traveling operation device outputs a traveling command for enabling the traveling device to travel, The controller: receiving an input of the travel command from the travel operation device, receiving an input of a set value of the engine speed from the speed setting device, and receiving an input of the seating signal from the seating sensor; a control unit for controlling the running of the running device when the control unit receives a command to enable the running of the running device, the set value of the engine speed is equal to or lower than a predetermined value at which the vehicle body can be stopped, and an operator is not seated in the operator seat, the control unit disables the running of the running device.

13. The car body and An engine installed in the vehicle body; a traveling device attached to the vehicle body and traveling using the output of the engine; A travel operation device that receives an operation from an operator and outputs a travel command to enable or stop the travel device; A rotation speed setting device for setting the rotation speed of the engine; a seating sensor that outputs a seating signal indicating a detection result of whether or not an operator is seated on the operator seat; a notification device for notifying an operator; and a controller. the rotation speed setting device sets an engine rotation speed to a predetermined value or less at which the vehicle body can be stopped, thereby making it possible to stop the traveling device even if the traveling operation device outputs a traveling command for enabling the traveling device to travel, The controller: receiving an input of the travel command from the travel operation device, receiving an input of a set value of the engine speed from the speed setting device, and receiving an input of the seating signal from the seating sensor; A work machine control system that causes the alarm device to issue an alert when there is a driving command indicating that the traveling device is capable of traveling, the set value of the engine speed is equal to or lower than a predetermined value at which the vehicle body can be stopped, and an operator is not seated in the operator seat.

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