Work machine control method, work machine control program, work machine control system, and work machine

Abstract

To provide a control method of a working machine, a control program for a working machine, a control system for a working machine, and a working machine that hardly allow a traveling unit to suddenly stop.SOLUTION: A control method of a working machine 3 is used for a working machine 3 that includes: a traveling unit 31 that has a traveling function; and a work unit 33 configured to be capable of executing work including lifting work. The control method of the working machine 3 is configured to execute restriction processing on the traveling motion of the traveling unit 31 when the working unit 33 is executing the lifting work and a working radius of the working unit 33 exceeds a specified value.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a work machine control method, a work machine control program, a work machine control system, and a work machine that are used in a work machine equipped with a working unit configured to be able to perform work including lifting work. [Background technology]

[0002] As related technology, a work machine (construction machine with a hook) is known in which an upper rotating body is mounted on a traveling section (lower traveling body) so that it can rotate, and a working section (working equipment) consisting of a boom, arm, bucket, etc. is mounted on the front of the rotating frame so that it can be raised and lowered (see, for example, Patent Document 1). In the work machine according to the related technology, a hook for lifting a load is mounted on the tip of the working section so that it hangs downward from the bracket of the bucket, and when performing lifting work (crane work), the load is suspended from the hook using rigging or the like. In this work machine, the traveling operation of the traveling section is stopped when the working radius of the working section exceeds a predetermined range. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-123362 Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned related technology, the traveling unit is forced to stop if the working radius exceeds a predetermined range. Therefore, for example, even if the working unit is performing excavation work, the traveling unit will stop if the working radius becomes too large, which may lead to a sudden stop of the traveling unit.

[0005] An object of the present invention is to provide a control method for a work machine, a control program for a work machine, a control system for a work machine, and a work machine in which sudden stops of the traveling part are unlikely to occur. [Means for solving the problem]

[0006] A construction machine control method according to one aspect of the present invention is used for a construction machine including a traveling unit having a traveling function and a working unit configured to perform work including a lifting operation. The construction machine control method includes, when the working unit is performing the lifting operation and the working radius of the working unit exceeds a specified value, executing a process to restrict the traveling operation of the traveling unit.

[0007] A work machine control program according to one aspect of the present invention is a program for causing one or more processors to execute the work machine control method.

[0008] A construction machine control system according to one aspect of the present invention is used in a construction machine that includes a traveling unit having a traveling function and a working unit configured to be able to perform work including a lifting work, and includes a restriction processing unit, wherein the restriction processing unit executes a restriction process on the traveling operation of the traveling unit when the working unit is performing the lifting work and the working radius of the working unit exceeds a specified value.

[0009] A work machine according to one aspect of the present invention includes the work machine control system, the traveling unit, and the working unit. [Effects of the Invention]

[0010] According to the present invention, it is possible to provide a control method for a work machine, a control program for a work machine, a control system for a work machine, and a work machine in which sudden stops of the traveling part are unlikely to occur. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a schematic perspective view showing the overall configuration of a work machine according to a first embodiment. [Figure 2] FIG. 2 is a schematic diagram showing a hydraulic circuit and the like of the work machine according to the first embodiment. [Figure 3] FIG. 3 is a schematic diagram showing the main parts of the working unit of the work machine according to the first embodiment. [Figure 4] FIG. 4 is a flowchart showing an example of the operation of the work machine control system according to the first embodiment. [Figure 5] FIG. 5 is an explanatory diagram showing an example of control of the current supplied to the proportional control valve in the work machine according to the first embodiment. [Figure 6] FIG. 6 is a schematic diagram showing the main parts of the working unit of the work machine according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The following description will discuss preferred embodiments of the present invention with reference to the accompanying drawings. The preferred embodiments are merely examples of the present invention and are not intended to limit the technical scope of the present invention.

[0013] (Embodiment 1) [1] Overall structure As shown in Figure 1, the work machine 3 according to this embodiment is equipped with a traveling section 31, a swivel section 32, and a working section 33 on a machine body 30. Furthermore, as shown in Figure 2, the work machine 3 is further equipped with a work machine control system 1 (hereinafter simply referred to as the "control system 1"). In addition, the machine body 30 is further equipped with a terminal device 2, an operating device, etc.

[0014] In this disclosure, the term "work machine" refers to various types of work machinery, and examples include work vehicles such as backhoes (including hydraulic excavators, mini excavators, etc.), wheel loaders, and carriers. The work machine 3 is equipped with a working unit 33 configured to be able to perform at least one task, including lifting. The work machine 3 is not limited to a "vehicle," but may be, for example, a work vessel, a work air vehicle such as a drone or multicopter, or the like. Furthermore, the work machine 3 is not limited to a construction machine (construction equipment), but may be, for example, an agricultural machine (farm equipment) such as a rice transplanter, tractor, or combine harvester. In this embodiment, unless otherwise specified, the work machine 3 is a backhoe with a lifting function (crane function) that can perform tasks such as excavation, leveling, trench digging, and loading in addition to lifting.

[0015] Furthermore, in this embodiment, for ease of explanation, the vertical direction when the work machine 3 is in a usable state is defined as the up-down direction D1. Furthermore, when the swivel unit 32 is in a non-swivel state, the front-to-rear direction D2 and the left-to-right direction D3 are defined based on the direction as seen by the user (operator) aboard the work machine 3 (the driving unit 321 thereof). In other words, all directions used in this embodiment are directions defined based on the machine body 30 of the work machine 3, with the direction in which the machine body 30 moves when the work machine 3 moves forward being "forward" and the direction in which the machine body 30 moves when the work machine 3 moves backward being "rear". Similarly, the direction in which the front end of the machine body 30 moves when the work machine 3 turns right being "rightward", and the direction in which the front end of the machine body 30 moves when the work machine 3 turns left being "leftward". However, these directions are not intended to limit the direction in which the work machine 3 is used (the direction in use).

[0016] The work machine 3 is equipped with an engine that serves as a power source. In the work machine 3, for example, the engine drives a hydraulic pump 41 (see FIG. 2), and hydraulic oil is supplied from the hydraulic pump 41 to hydraulic actuators (including hydraulic motors 43 and hydraulic cylinders 44, etc.) in various parts of the machine body 30, thereby driving the machine body 30. Furthermore, the work machine 3 is controlled, for example, by a user (operator) aboard the driving section 321 of the machine body 30 operating an operating lever or the like of an operating device.

[0017] In this embodiment, as described above, it is assumed that the work machine 3 is a riding-type backhoe, and therefore the working unit 33 is driven in accordance with the operation of a user (operator) riding in the driving unit 321 to perform work such as excavation work. The driving unit 321 on which the user rides is provided on the swivel unit 32.

[0018] The traveling unit 31 has a traveling function and is configured to be able to travel (including turn) on the ground. The traveling unit 31 has, for example, a pair of left and right crawlers 311 and a blade 312. The traveling unit 31 further has a traveling hydraulic motor 43 (hydraulic actuator) for driving the crawlers 311.

[0019] The swivel unit 32 is located above the travel unit 31 and is configured to be swivelable relative to the travel unit 31 around a rotation axis that is aligned in the vertical direction. The swivel unit 32 has a hydraulic motor (hydraulic actuator) for rotation and the like. In addition to a driving unit 321, the swivel unit 32 is equipped with an engine, a hydraulic pump 41 and the like. Furthermore, a boom bracket 322 to which the working unit 33 is attached is provided at the front end of the swivel unit 32.

[0020] The working unit 33 is configured to be able to perform work including lifting work. The working unit 33 is supported by the boom bracket 322 of the swivel unit 32 and performs work. The working unit 33 has a bucket 331, a boom 332, an arm 333, a hook 334, etc. The working unit 33 also has hydraulic actuators (including hydraulic cylinders 44, hydraulic motors, etc.) for driving each part.

[0021] The bucket 331 is a type of attachment (work implement) that is attached to the body 30 of the work machine 3, and is any tool selected from multiple types of attachments depending on the type of work to be done. As an example, the bucket 331 is removably attached to the body 30 and is replaced depending on the type of work to be done. In addition to the bucket 331, attachments for the work machine 3 include, for example, various tools such as breakers, augers, crushers, forks, fork claws, steel frame cutters, asphalt cutters, brush cutters, rippers, mulchers, tiltrotators, and tampers. The working unit 33 performs work by driving the bucket 331 with power from a drive device.

[0022] The boom 332 is rotatably supported by the boom bracket 322 of the swivel section 32. Specifically, the boom 332 is supported by the boom bracket 322 so as to be rotatable around a rotation axis that extends in the horizontal direction. The boom 332 has a shape that extends upward from a base end supported by the boom bracket 322. The arm 333 is connected to the tip of the boom 332. The arm 333 is supported relative to the boom 332 so as to be rotatable around a rotation axis that extends in the horizontal direction. A bucket 331 is attached to the tip of the arm 333.

[0023] The working unit 33 operates by receiving power from an engine as a power source. Specifically, the engine drives a hydraulic pump 41, and hydraulic oil is supplied from the hydraulic pump 41 to hydraulic actuators (hydraulic cylinder 44, etc.) of the working unit 33, thereby operating each part of the working unit 33 (bucket 331, boom 332, and arm 333).

[0024] Here, in the work machine 3 according to this embodiment, the working unit 33 is configured to be able to perform a plurality of tasks, including lifting work. In this embodiment, the work machine 3 is a backhoe with a lifting function, and the working unit 33 is configured to be able to perform lifting work in addition to excavation work with the bucket 331. The hook 334 is located at the tip of the working unit 33. Specifically, the hook 334 is provided so as to protrude downward from the bucket 331. When lifting work is not being performed, the hook 334 is housed, for example, in the bucket link 335 that connects the arm 333 and the bucket 331, so that the hook 334 is less likely to get in the way when performing excavation work using the bucket 331, for example.

[0025] When performing a lifting operation, the working unit 33 can load and unload the load (object) by operating the boom 332 and the arm 333 with the load (object) suspended from the hook 334. Furthermore, with the load suspended from the hook 334 provided at the tip of the working unit 33, the swivel unit 32 can rotate to rotate the load around the rotation axis of the swivel unit 32.

[0026] During such lifting operations, the working radius of the working unit 33 and the weight of the suspended load, among other factors, affect the stability of the posture of the work machine 3. For example, the smaller the working radius of the working unit 33, the more likely it is that the posture of the work machine 3 will be stable. In this disclosure, the "working radius" refers to the horizontal distance from the center of rotation of the working unit 33 to a vertical line passing through the center of the hook 334 (jib point pin), and more specifically, it is the distance from the rotation axis of the swivel unit 32 to the center of the hook 334 in a plan view. Therefore, the larger the working radius of the working unit 33, the larger the orbital circle of the suspended load when the working unit 33 (together with the swivel unit 32) is in a plan view. Since the lengths (dimensions) of the boom 332 and arm 333 are known, the maximum value of the working radius is also known.

[0027] Here, the working radius of the working unit 33 is set as a specified value, which is a value that is permissible when performing a lifting operation while the traveling unit 31 is traveling. In other words, the "specified value" in this disclosure refers to the working radius that is permissible when performing a lifting operation while the traveling unit 31 is traveling, and is expressed, for example, as a ratio (percentage) of the maximum working radius (maximum radius). If the working radius is equal to or less than the specified value, the lifting operation is permitted even when the traveling unit 31 is traveling. As an example, the specified value is preferably equal to or greater than 50% and equal to or less than 90% of the maximum working radius. More preferably, the specified value is set to equal to or greater than 60% of the maximum working radius. Also, more preferably, the specified value is set to equal to or less than 80% of the maximum working radius. The specified value may be set in advance, or may be freely set (changed) by the user, for example, in a maintenance mode or the like.

[0028] Particularly in this embodiment, the working unit 33 has an articulated structure in which the boom 332 and the arm 333 are configured to be independently rotatable. That is, by each of the boom 332 and the arm 333 rotating about a horizontal rotation axis, the articulated working unit 33 including the boom 332 and the arm 333 can be extended or folded as a whole. Therefore, by extending the working unit 33 along the horizontal plane, the working radius of the working unit 33 increases, and conversely, by folding the working unit 33, the working radius of the working unit 33 decreases. The operation of the working unit 33 when increasing the working radius is called the "extension operation," and the operation of the working unit 33 when decreasing the working radius is called the "retraction operation."

[0029] Here, the machine body 30 is provided with a boom sensor 336 and an arm sensor 337 (see FIG. 2) that detect at least the angles (boom angle and arm angle) of the boom 332 and the arm 333, respectively. The boom sensor 336 detects the boom angle, and the arm sensor 337 detects the arm angle. The boom sensor 336 and the arm sensor 337 are connected to the control system 1 and output the detected angles to the control system 1. The control system 1 can calculate the working radius of the working unit 33 based on the angles detected by the boom sensor 336 and the arm sensor 337 and the known lengths of the boom 332 and the arm 333. The machine body 30 is also provided with pressure sensors and the like that are arranged on the bottom side and rod side of the boom 332, etc. The control system 1 can calculate the load of the suspended load by using the outputs of the pressure sensors in addition to the outputs of the boom sensor 336 and the arm sensor 337.

[0030] Like the working unit 33, the traveling unit 31 and the swivel unit 32 each receive power from an engine as a power source and operate. That is, the swivel unit 32 and the traveling unit 31 operate when hydraulic oil is supplied from the hydraulic pump 41 to the hydraulic motor 43 of the traveling unit 31 and the hydraulic motor of the swivel unit 32, etc.

[0031] As described above, the engine functions as a power source that supplies power to each part. Here, the engine is mounted on the slewing part 32 together with the hydraulic pump 41 and the like. In this embodiment, as an example, the engine is a diesel engine. The engine is driven by fuel (here, diesel) supplied from a fuel tank. The fuel tank is equipped with a fuel level sensor that detects the remaining amount of fuel, and the fuel level sensor outputs an electric signal (sensor signal) corresponding to the detected remaining amount of fuel.

[0032] Fig. 2 schematically shows the hydraulic circuit and electrical circuit (electrical connection relationships) of the work machine 3 according to this embodiment. In Fig. 2, solid lines indicate high-pressure oil passages (for hydraulic oil), dotted lines indicate low-pressure oil passages (for pilot oil), and dashed arrows indicate electrical signal paths.

[0033] As shown in FIG. 2, the work machine 3 is equipped with a hydraulic pump 41, a hydraulic motor 43, and a hydraulic cylinder 44 (not shown in FIG. 2), as well as a pilot pump 42, a remote control valve 45, a proportional control valve 46, a state detection unit 49, etc.

[0034] Hydraulic oil from a hydraulic pump 41 driven by the engine is supplied to a hydraulic motor 43 of the traveling unit 31 and a hydraulic cylinder 44 of the working unit 33. This drives hydraulic actuators such as the hydraulic motor 43 and the hydraulic cylinder 44.

[0035] Hydraulic actuators such as the hydraulic motor 43 and the hydraulic cylinder 44 are provided with pilot-type directional control valves (control valves) that can switch the direction and flow rate of hydraulic oil from the hydraulic pump 41. These directional control valves are driven by the supply of pilot oil, which serves as an input command, from the pilot pump 42.

[0036] Here, a remote control valve 45 is provided in a supply path of pilot oil to the directional control valve corresponding to the hydraulic motor 43 of the traveling unit 31. The remote control valve 45 outputs a travel operation command for the traveling unit 31 in response to operation of the control lever. The travel operation command instructs the traveling operation of the traveling unit 31. In addition, an (electromagnetic) proportional control valve 46 is inserted between the remote control valve 45 and the pilot pump 42. The proportional control valve 46 is connected to the control system 1 and operates in response to an electric signal (supply current) from the control system 1. In this embodiment, as an example, the proportional control valve 46 is an inverse proportional valve, and the larger the supply current, the more the output of the traveling hydraulic motor 43 is reduced.

[0037] Similarly, a remote control valve is provided in the supply path for pilot oil to the directional control valve corresponding to the hydraulic cylinder 44 of the working unit 33. This remote control valve outputs a work operation command for the working unit 33 in response to the operation of the operating lever. The work operation command instructs the working unit 33 to deploy, retract, etc.

[0038] The state detection unit 49 detects the operation state of the remote control valve 45. In this embodiment, as an example, the state detection unit 49 is a pressure sensor inserted into an oil path for pilot oil. The state detection unit 49 detects the operation state of the remote control valve 45, thereby detecting the operating state of the traveling hydraulic motor 43. The state detection unit 49 is connected to the control system 1, and outputs the detection result (i.e., the operating state of the hydraulic motor 43) to the control system 1.

[0039] The control system 1 is mainly composed of a computer system having one or more processors such as a CPU (Central Processing Unit) and one or more memories such as a ROM (Read Only Memory) and a RAM (Random Access Memory), and executes various processes (information processing). In this embodiment, the control system 1 is an integrated controller that controls the entire work machine 3, and is composed of, for example, an electronic control unit (ECU). However, the control system 1 may be provided separately from the integrated controller. The control system 1 will be explained in detail in the section "[2] Configuration of the Control System."

[0040] The terminal device 2 is disposed in the driving section 321 of the machine body 30, and is a user interface for receiving operation inputs from a user (operator) and outputting various information to the user. The terminal device 2 receives various operations from the user, for example, by outputting electrical signals in response to the user's operations. This allows the user (operator) to view the display screen displayed on the terminal device 2 and to operate the terminal device 2 as necessary.

[0041] 2, the terminal device 2 includes a control unit 21, an operation unit 22, and a display unit 23. The terminal device 2 is configured to be able to communicate with the control system 1, and is able to send and receive data to and from the control system 1. In this embodiment, as an example, the terminal device 2 is a dedicated device used in the work machine 3.

[0042] The control unit 21 controls the terminal device 2. Specifically, the control unit 21 outputs an electrical signal in response to a user operation received by the operation unit 22, generates a display screen, and displays it on the display unit 23.

[0043] The operation unit 22 is a user interface for accepting operation inputs by a user (operator) to a display screen displayed on the display unit 23. The operation unit 22 accepts various operations by the user, for example, by outputting an electrical signal in response to the user's operation. In the present embodiment, as an example, the operation unit 22 includes a plurality of mechanical push button switches. The operation unit 22 may also include a touch panel, an operation dial, etc.

[0044] The display unit 23 is a user interface for presenting information to a user (operator), such as a liquid crystal display or an organic EL display that displays various types of information. The display unit 23 presents various types of information to the user by displaying them. In this embodiment, as an example, the display unit 23 is a full-color liquid crystal display with a backlight.

[0045] In addition to the above-described configuration, the machine body 30 further includes an operating lever, a communication terminal, a fuel tank, a battery, etc. Furthermore, the machine body 30 is equipped with sensors (including a camera) for monitoring the operating state of the machine body 30, such as a coolant temperature sensor, a hydraulic oil temperature sensor, a tachometer that measures the engine rotation speed, an hour meter that measures the operating time, and a camera that captures images of the periphery of the machine body 30. The machine body 30 also includes sensors that detect the state of the cut-off lever, gate lock lever, starter key switch, etc.

[0046] [2] Control system configuration Next, the configuration of the control system 1 according to this embodiment will be described with reference to Figure 2. The control system 1 is a component of the work machine 3, and together with the machine body 30 and the like, constitutes the work machine 3. In other words, the work machine 3 according to this embodiment is equipped with at least the control system 1, a traveling unit 31, and a working unit 33.

[0047] As shown in FIG. 2, the control system 1 includes an operation determination unit 11, a travel determination unit 12, a working radius determination unit 13, and a restriction processing unit 14. The control system 1 is configured to be able to communicate with devices provided in various parts of the machine body 30. That is, at least a boom sensor 336, an arm sensor 337, a proportional control valve 46, and a state detection unit 49 are connected to the control system 1. This enables the control system 1 to acquire detection results from the boom sensor 336, the arm sensor 337, etc., and to control the proportional control valve 46, etc. Furthermore, the control system 1 is also connected to a terminal device 2 so as to be able to communicate with the control system 1. Here, the control system 1 may exchange this information (data) with each device directly, or indirectly via a relay or the like.

[0048] The operation determination unit 11 determines the operation to be performed by the working unit 33. That is, the operation determination unit 11 determines whether the working unit 33 is performing a lifting operation or an operation other than the lifting operation (such as an excavation operation). In this embodiment, the operation mode of the working unit 33 is configured to allow selection of one operation mode from a plurality of operation modes. The plurality of operation modes here includes at least a crane mode and an alternative mode. The crane mode is an operation mode that causes the working unit 33 to perform a lifting operation. The alternative mode is an operation mode that causes the working unit 33 to perform an operation other than the lifting operation. In this embodiment, as an example, the alternative mode includes an excavation mode that causes the working unit 33 to perform an excavation operation. That is, in this embodiment, the operation mode of the working unit 33 is selected alternatively from a plurality of operation modes including a crane mode for lifting operation and an excavation mode (another mode) for excavation operation. With this configuration, by switching the operation mode, it is possible to cause the working unit 33 to perform not only a lifting operation but also an excavation operation.

[0049] In the present embodiment, as an example, the operation mode is switched by the user (operator) operating the terminal device 2. That is, when the user operates the operation unit 22 of the terminal device 2 to select the crane mode, the control system 1 receives this operation and switches the operation mode of the working unit 33 to the crane mode. On the other hand, when the user operates the operation unit 22 of the terminal device 2 to select the excavation mode, the control system 1 receives this operation and switches the operation mode of the working unit 33 to the excavation mode. In this way, the control system 1 alternatively selects one operation mode or the other in accordance with the operation of the operation unit 22.

[0050] In the control system 1 according to this embodiment, whether or not the working unit 33 is performing lifting work is determined by utilizing the fact that one operation mode can be alternatively selected from a plurality of operation modes, including the crane mode and another mode (excavation mode, etc.). In other words, the operation determination unit 11 determines that the working unit 33 is performing lifting work when the crane mode is selected. According to this configuration, in a work machine 3 that is capable of selecting an operation mode, whether or not the working unit 33 is performing lifting work is determined based on the selected operation mode, making it easy to determine whether or not the working unit 33 is performing lifting work.

[0051] The travel determination unit 12 determines whether the travel unit 31 is in a travelling operation. In the present embodiment, as an example, the travel determination unit 12 determines whether the travel unit 31 is in a travelling operation based on the detection result of the state detection unit 49 (the operation state of the remote control valve 45). In other words, regardless of the travelling speed, when the hydraulic motor 43 of the travel unit 31 is driven, the travel determination unit 12 determines that the travelling operation is in progress based on the detection result of the state detection unit 49 at that time. On the other hand, when the hydraulic motor 43 of the travel unit 31 is not driven, that is, when it is stopped, the travel determination unit 12 determines that the travelling operation is not in progress based on the detection result of the state detection unit 49 at that time.

[0052] The working radius determination unit 13 determines whether the working radius exceeds a specified value. The specified value here is the working radius allowed when performing lifting work while the traveling unit 31 is traveling, and is expressed as a ratio (percentage) of the maximum value of the working radius (maximum radius). In this embodiment, as an example, the working radius determination unit 13 calculates the working radius of the working unit 33 based on the angles (boom angle and arm angle) detected by the boom sensor 336 and the arm sensor 337, and the lengths (dimensions) of the boom 332 and the arm 333. The working radius determination unit 13 compares the working radius calculated based on the angles detected by the boom sensor 336 and the arm sensor 337 with the specified value to determine whether the working radius exceeds the specified value.

[0053] The restriction processing unit 14 executes a restriction process on the traveling operation of the traveling unit 31 when a predetermined restriction condition is met. Here, the restriction condition includes that the working unit 33 is performing a lifting operation and the working radius of the working unit 33 exceeds a specified value. In other words, the restriction processing unit 14 executes a restriction process on the traveling operation of the traveling unit 31 when the working unit 33 is performing a lifting operation and the working radius of the working unit 33 exceeds a specified value. In this disclosure, the term "restriction process" refers to a process that acts in some way to restrict the traveling operation of the traveling unit 31. As an example, the restriction process includes a process of prohibiting the traveling operation of the traveling unit 31 (making the traveling operation impossible), a process of slowing down the speed (traveling speed) of the traveling operation of the traveling unit 31, and a process of restricting the allowable area for the traveling operation of the traveling unit 31.

[0054] Specifically, the restriction processing unit 14 executes the restriction processing based on the determination results of the operation determination unit 11, the travel determination unit 12, and the working radius determination unit 13. That is, the restriction processing unit 14 executes the restriction processing when the operation determination unit 11 determines that the working unit 33 is performing a lifting operation and the working radius determination unit 13 determines that the working radius of the working unit 33 exceeds a specified value. Furthermore, the restriction processing unit 14 changes the content of the restriction processing depending on the determination result of the travel determination unit 12 (whether the traveling unit 31 is in a traveling operation). Also, in the present embodiment, as an example, the restriction processing unit 14 executes the restriction processing on the traveling operation of the traveling unit 31 by controlling a proportional control valve 46 connected to a remote control valve 45 provided in a supply path of pilot oil to a directional control valve corresponding to the hydraulic motor 43 of the traveling unit 31.

[0055] [3] Control method for work machine An example of a control method for the work machine 3 (hereinafter simply referred to as a "control method") that is executed mainly by the control system 1 will be described below with reference to FIGS.

[0056] The control method according to this embodiment is executed by a control system 1 whose main component is a computer system, and in other words, is embodied in a work machine control program (hereinafter simply referred to as a "control program"). In other words, the control program according to this embodiment is a computer program for causing one or more processors to execute each process related to the control method. Such a control program may be executed, for example, by the control system 1 and the terminal device 2 working together.

[0057] Here, the control system 1 executes the various processes described below related to the control method when a specific, preset start operation is performed to execute the control program. The start operation is, for example, an operation to start the engine of the work machine 3. On the other hand, the control system 1 ends the various processes described below related to the control method when a specific, preset end operation is performed. The end operation is, for example, an operation to stop the engine of the work machine 3.

[0058] [3.1] Overall processing First, the overall flow of processing related to the control method will be described with reference to Fig. 4. Fig. 4 is a flowchart showing an example of processing related to the restriction processing in particular of the control method.

[0059] 4, first, the control system 1 selects an operation mode for the working unit 33 (S1). In this embodiment, when an operation to select the crane mode is performed on the operation unit 22 of the terminal device 2, the control system 1 selects the crane mode as the operation mode for the working unit 33. In short, the control method according to this embodiment includes selecting (processing) one operation mode from a plurality of operation modes including the crane mode and another mode (excavation mode, etc.).

[0060] In step S2, the work determination unit 11 of the control system 1 determines whether or not the crane mode is selected. If the crane mode is selected (S2: Yes), the work determination unit 11 determines that the working unit 33 is performing a lifting operation, and shifts the process to step S3. On the other hand, if another mode (excavation mode, etc.) is selected (S2: No), the work determination unit 11 determines that the working unit 33 is not performing a lifting operation, and shifts the process to step S1.

[0061] In step S3, the working radius determination unit 13 of the control system 1 determines whether the working radius exceeds a specified value. The specified value here is the working radius allowed when performing lifting work while the traveling unit 31 is traveling, and is expressed as a ratio (percentage) of the working radius to the maximum value (maximum radius). In step S3, for example, the working radius of the working unit 33, determined based on the angles detected by the boom sensor 336 and the arm sensor 337, is compared with the specified value. If the working radius exceeds the specified value (S3: Yes), the working radius determination unit 13 transitions the process to step S4. On the other hand, if the working radius is equal to or less than the specified value (S3: No), the working radius determination unit 13 transitions the process to step S1.

[0062] In step S4, the travel determination unit 12 of the control system 1 determines whether the travel unit 31 is in a travelling operation. In the present embodiment, as an example, the travel determination unit 12 determines whether the travel unit 31 is in a travelling operation based on the detection result of the state detection unit 49 (the operation state of the remote control valve 45). Regardless of the travelling speed, if the hydraulic motor 43 of the travel unit 31 is driven, the travel determination unit 12 determines that the travelling operation is in progress (S4: Yes), and shifts the process to step S5. On the other hand, if the hydraulic motor 43 of the travel unit 31 is not driven, i.e., is stopped, the travel determination unit 12 determines that the travelling operation is not in progress (S4: No), and shifts the process to step S6.

[0063] In steps S5 and S6, the restriction processing unit 14 of the control system 1 executes the restriction process. When steps S5 and S6 are completed, the control system 1 ends the series of processes related to the restriction process.

[0064] In step S5, the restriction processing unit 14 of the control system 1 executes the restriction process, which is a process of decelerating and then stopping the traveling unit 31. That is, the restriction process includes a deceleration process that reduces the traveling speed of the traveling unit 31. With this configuration, the restriction process is executed while the traveling unit 31 is traveling, so that the traveling speed of the traveling unit 31 is first reduced, making it less likely that the traveling unit 31 will suddenly stop. Furthermore, the restriction process includes a stop process that stops the traveling unit 31 after the deceleration process. With this configuration, the traveling unit 31 stops after the traveling speed of the traveling unit 31 is reduced, making it less likely that the traveling unit 31 will suddenly stop, even though the traveling operation of the traveling unit 31 is stopped. When step S5 is completed, the control system 1 ends the series of processes related to the restriction process.

[0065] In step S5, the restriction processor 14 performs deceleration and stop processing by controlling the proportional control valve 46 connected to the remote control valve 45 provided in the supply path of pilot oil to the directional control valve corresponding to the hydraulic motor 43 of the traveling unit 31. Specifically, the restriction processor 14 performs deceleration and stop processing by controlling the current supplied to the proportional control valve 46. In other words, the restriction processing includes control of the current supplied to the proportional control valve 46 inserted between the remote control valve 45 that outputs the travel operation command for the traveling unit 31 and the pilot pump 42 that supplies pilot oil to the remote control valve 45. With this configuration, the restriction processing including the deceleration processing can be implemented relatively easily.

[0066] In step S6, the restriction processing unit 14 of the control system 1 executes a travel prohibition process as the restriction process, which prohibits the travel unit 31 from starting a travel operation (starting travel). That is, the restriction process includes a process of prohibiting the travel unit 31 from starting a travel operation. In short, if the travel unit 31 is not currently traveling (S4: No), the restriction processing unit 14 executes the travel prohibition process so that the travel unit 31 does not start traveling. According to this configuration, in a state where the restriction condition is satisfied, the travel unit 31 is prohibited from starting to travel in the first place, thereby preventing the travel unit 31 from suddenly stopping. When step S6 is completed, the control system 1 ends the series of processes related to the restriction process.

[0067] Here, in step S6, the restriction processing unit 14 performs the traveling prohibition process by controlling the proportional control valve 46 connected to the remote control valve 45 provided in the supply path of pilot oil to the directional control valve corresponding to the hydraulic motor 43 of the traveling unit 31. Specifically, the restriction processing unit 14 performs the traveling prohibition process by controlling the current supplied to the proportional control valve 46.

[0068] Incidentally, steps S5 and S6 are processes that are executed only when it is determined that the working unit 33 is performing a lifting operation (crane mode is selected) (S2: Yes) and that the working radius of the working unit 33 exceeds a specified value (S3: Yes), so the restriction process is executed only when the restriction conditions are met. In short, the control method according to this embodiment includes the execution of a restriction process (process) on the traveling operation of the traveling unit 31 when the working unit 33 is performing a lifting operation and the working radius of the working unit 33 exceeds a specified value.

[0069] According to this configuration, if the working unit 33 is performing a lifting operation and the working radius of the working unit 33 exceeds a specified value, the limiting process can limit the traveling operation of the traveling unit 31. This makes it possible, for example, to prevent the traveling operation from continuing when the working radius exceeds a predetermined range. Furthermore, the limiting process requires that the working unit 33 is performing a lifting operation as one of the conditions, and the limiting process is not executed if the working unit 33 is not performing a lifting operation. Therefore, for example, even if a user (operator) accidentally increases the working radius of the working unit 33 while the traveling unit 31 is traveling, the traveling unit 31 will not be brought to a sudden stop unless the working unit 33 is performing a lifting operation. Therefore, the work machine 3 according to this embodiment has the advantage that the traveling unit 31 is less likely to stop suddenly.

[0070] Furthermore, in this embodiment, steps S5 and S6 are processes that are executed only when it is determined that the working radius of the working unit 33 exceeds the specified value (S3: Yes). That is, in this embodiment, the restriction process is executed when the working radius exceeds the specified value and is not executed when the working radius is equal to or less than the specified value. Therefore, for example, even when the crane mode is selected (S2: Yes) and the traveling unit 31 is in traveling operation (S4: Yes), the deployment operation of the working unit 33 is permitted until the deployment operation of the working unit 33 causes the working radius to reach the specified value. With this configuration, as long as the working radius is within the range equal to or less than the specified value, the deployment operation of the working unit 33 can be performed without being affected by the restriction process, and the operability of the working unit 33 is less likely to be impaired.

[0071] However, the flowchart shown in FIG. 4 is merely an example, and processes may be added or omitted as appropriate, and the order of processes may be changed as appropriate.

[0072] [3.2] Restriction processing Next, a specific example of the restriction process of the control method according to this embodiment will be described with reference to Fig. 5. Fig. 5 shows an example of the current supplied to the proportional control valve 46 in each of step S5 (deceleration stop process) and step S6 (travel prohibition process) in Fig. 4. That is, the graph shown in the upper part of Fig. 5 is an example of control of the current supplied when the traveling unit 31 is traveling (S4: Yes), and the graph shown in the lower part of Fig. 6 is an example of control of the current supplied when the traveling unit 31 is not traveling (S4: No).

[0073] As shown in the upper part of FIG. 5 , during the deceleration / stop process, which is a process for stopping the traveling unit 31 after the deceleration process, the limiting unit 14 controls the current supplied to the proportional control valve 46 to gradually increase to a target value I1. That is, if the working radius of the working unit 33 exceeds a specified value during the traveling operation of the traveling unit 31, the limiting unit 14 controls the current supplied to the proportional control valve 46 to gradually increase from time t0. In this embodiment, since the proportional control valve 46 is an inverse proportional valve, the larger the current supplied, the more the pilot oil to the directional control valve corresponding to the traveling hydraulic motor 43 is suppressed, reducing the output of the hydraulic motor 43 and gradually decelerating the traveling speed of the traveling unit 31. Then, when the current supplied to the proportional control valve 46 reaches the target value I1, the traveling unit 31 stops at time t1. In other words, the limiting process includes gradually increasing the current supplied to the proportional control valve 46 to the target value I1. According to this configuration, the current supplied to the proportional control valve 46 can gently decelerate the traveling speed of the traveling unit 31, making it possible to smoothly stop the traveling unit 31. In Fig. 5, the limiting unit 14 linearly increases the current supplied to the proportional control valve 46 over time, but this is not limiting, and the limiting unit 14 may increase the current supplied exponentially or in stages, for example.

[0074] On the other hand, during travel prohibition processing to prohibit the traveling unit 31 from traveling, as shown in the lower part of FIG. 5, the restriction processor 14 switches the supply current to the proportional control valve 46 from 0 (zero) to a target value I1. In other words, while the traveling unit 31 is stopped, the restriction processor 14 sets the supply current to 0 (zero) when the working radius of the working unit 33 is equal to or less than a specified value L1, and sets the supply current to the target value I1 when the working radius of the working unit 33 exceeds the specified value L1. As a result, when the working unit 33 is deployed while the traveling unit 31 is stopped, if the working radius of the working unit 33 exceeds the specified value L1, the restriction processor 14 switches the supply current to the proportional control valve 46 to the target value I1. When the supply current to the proportional control valve 46 switches to the target value I1, the pilot oil to the directional control valve corresponding to the traveling hydraulic motor 43 is shut off, and the traveling unit 31 is prohibited from starting to travel.

[0075] [4] Variation Below, we will list some modified examples of embodiment 1. The modified examples explained below can be applied in appropriate combinations.

[0076] The control system 1 in the present disclosure includes a computer system. The computer system is primarily composed of one or more processors and one or more memories as hardware. The functions of the control system 1 in the present disclosure are realized by the processor executing a program recorded in the memory of the computer system. The program may be pre-recorded in the memory of the computer system, provided via a telecommunications line, or provided by being recorded on a non-transitory recording medium such as a memory card, optical disk, or hard disk drive that is readable by the computer system. In addition, some or all of the functional units included in the control system 1 may be configured with electronic circuits.

[0077] Furthermore, it is not essential for the control system 1 that at least some of the functions of the control system 1 are concentrated in one housing, and the components of the control system 1 may be distributed across multiple housings. Conversely, in embodiment 1, functions that are distributed across multiple devices (for example, the control system 1 and the terminal device 2) may be concentrated in one housing. Furthermore, at least some of the functions of the control system 1 may be realized by the cloud (cloud computing) or the like.

[0078] Furthermore, the power source of the work machine 3 is not limited to a diesel engine, and may be, for example, an engine other than a diesel engine, or may be a motor (electric motor), or a hybrid power source including an engine and a motor (electric motor).

[0079] The terminal device 2 is not limited to a dedicated device, but may be a general-purpose terminal such as a laptop computer, a tablet terminal, or a smartphone. Furthermore, the display unit 23 is not limited to a device that directly displays a display screen, such as a liquid crystal display or an organic EL display, but may be configured to display a display screen by projection, such as a projector.

[0080] Furthermore, modes other than push button switches, touch panels, and operation dials may be adopted as the mode of inputting information to the operation unit 22. For example, the operation unit 22 may adopt modes such as a keyboard, a pointing device such as a mouse, voice input, gesture input, or input of an operation signal from another terminal.

[0081] Furthermore, the determination as to whether the traveling unit 31 is in a traveling operation may be made without relying on the detection result of the state detection unit 49. As one example, the determination as to whether the traveling unit 31 is in a traveling operation may be made based on the position of the spool of the directional control valve (control valve), the operating state of the operation lever corresponding to the remote control valve 45, the output (rotation) of the hydraulic motor 43 for traveling, or the like.

[0082] Furthermore, it is not essential that the restriction process include a deceleration process, and it is not essential that the restriction process include a stop process. Furthermore, it is not essential that the restriction process include a travel prohibition process that prohibits the start of the travel operation of the travel unit 31. For example, the restriction process may include only one of the deceleration process, the stop process, and the travel prohibition process. Furthermore, it is not essential that the other mode include the excavation mode, and the other mode may be any mode other than the crane mode. Furthermore, it is not essential that the limiting process include control of the current supplied to the proportional control valve 46, and it is not essential that the limiting process gradually increase the current supplied to the proportional control valve 46 up to the target value I1.

[0083] (Embodiment 2) As shown in Figure 6, the work machine 3 according to this embodiment differs from the work machine 3 according to the first embodiment in that it is equipped with a storage sensor 338 that detects the storage state of the hook 334. Hereinafter, the same components as those in the first embodiment will be given the same reference numerals and explanations thereof will be omitted as appropriate.

[0084] That is, when performing excavation work or the like using the bucket 331, the hook 334 is stored in the bucket link 335 so that the hook 334 does not get in the way. The storage sensor 338 is a sensor that detects whether the hook 334 is stored in the bucket link 335 or not, and is made up of, for example, a non-contact optical sensor. The storage sensor 338 is connected to the control system 1, and outputs the detected angle to the control system 1.

[0085] In the work machine 3 according to this embodiment, the operation mode is switched by the user (operator) withdrawing the hook 334 from the bucket link 335. In other words, when the user operates the hook 334 so as to withdraw it from the bucket link 335, the control system 1 receives the output of the storage sensor 338 at this time and switches the operation mode of the working unit 33 to the crane mode. On the other hand, when the user operates the hook 334 so as to store (store) the hook 334 in the bucket link 335, the control system 1 receives the output of the storage sensor 338 at this time and switches the operation mode of the working unit 33 to the excavation mode. In this way, the control system 1 alternatively selects one operation mode or the other in accordance with the output of the storage sensor 338.

[0086] In this embodiment, the work determination unit 11 determines whether or not the crane mode has been selected based on the output of the storage sensor 338. That is, if the hook 334 is not housed (stored) in the bucket link 335, the work determination unit 11 determines that the operation mode of the working unit 33 is in the crane mode. If the hook 334 is housed (stored) in the bucket link 335, the work determination unit 11 determines that the operation mode of the working unit 33 is in another mode (excavation mode, etc.). In short, whether or not the crane mode has been selected is determined based on the state of the hook 334 attached to the working unit 33. With this configuration, even in a work machine in which the operation mode of the working unit 33 cannot be switched by the operation unit 22 of the terminal device 2, it is possible to determine that the crane mode has been selected, that is, that the working unit 33 is performing lifting work.

[0087] The configuration according to the second embodiment can be adopted in appropriate combination with the various configurations (including modified examples) described in the first embodiment. [Explanation of symbols]

[0088] 1. Work machine control system 3. Work machinery 14 Restriction Processing Unit 31 Running part 33 Working Section 42 Pilot pump 45 Remote control valve 46 Proportional control valve 334 Hook L1 target value

Claims

1. The present invention is used in a work machine including a traveling unit having a traveling function and a working unit configured to be able to perform work including lifting work, When the working unit is performing the lifting work and the working radius of the working unit exceeds a specified value, a restriction process is executed on the traveling operation of the traveling unit, The restriction process includes a deceleration process of reducing the running speed of the running unit while the running unit is running from a speed determined in accordance with a running operation, and a process of prohibiting the running unit from starting the running operation in response to a running operation while the running unit is stopped. A method for controlling a work machine.

2. the restriction process includes a stop process of stopping the traveling unit after the deceleration process. A method for controlling a work machine according to claim 1.

3. selecting one operation mode from a plurality of operation modes including a crane mode in which the working unit performs the lifting operation and another mode in which the working unit performs an operation other than the lifting operation, determining that the working unit is performing the lifting operation when the crane mode is selected; A control method for a work machine according to claim 1 or 2.

4. The other mode includes an excavation mode in which the working unit performs excavation work. The method for controlling a work machine according to claim 3.

5. Whether the crane mode is selected or not is determined based on a state of a hook attached to the work unit. A control method for a work machine according to claim 3 or 4.

6. The limiting process includes controlling a supply current to a proportional control valve inserted between a remote control valve that outputs a travel operation command for the traveling unit and a pilot pump that supplies pilot oil to the remote control valve. A control method for a work machine according to any one of claims 1 to 5.

7. the limiting process includes gradually increasing a current supplied to the proportional control valve up to a target value. A method for controlling a work machine according to claim 6.

8. A control method for a work machine according to any one of claims 1 to 7, A control program for a work machine for execution by one or more processors.

9. The present invention is used in a work machine including a traveling unit having a traveling function and a working unit configured to be able to perform work including lifting work, a restriction processing unit that executes a restriction process on the traveling operation of the traveling unit when the working unit is performing the lifting work and the working radius of the working unit exceeds a specified value; The restriction process includes a deceleration process of reducing the running speed of the running unit while the running unit is running from a speed determined in accordance with a running operation, and a process of prohibiting the running unit from starting the running operation in response to a running operation while the running unit is stopped. Control systems for work machines.

10. A work machine control system according to claim 9; The running portion; The working unit, Work machinery.

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