Work machinery

Abstract

To provide a work machine that can suppress unintended operation of a work machine due to erroneous travel operation.SOLUTION: A work machine comprises an attitude detection device 50 that detects an attitude of a front work device 1A. When the front work device 1A (a bucket 10 thereof) passes a part lower than a lower traveling body 11 by a predetermined amount, a controller (a control device) 40 stores a relative angle between an upper revolving body 12 and the lower traveling body 11 at that time, and sets an area corresponding the angle as an entry-prohibited area. A travel operation is suppressed when a travel operation to the entry-prohibited area is performed.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a work machine that improves the traveling operation of a work machine such as a hydraulic excavator that has a traveling body and an upper rotating body that is rotatably provided above the traveling body. [Background technology]

[0002] Generally, there are work machines such as hydraulic excavators that have a running body and an upper rotating body that is rotatably mounted on the running body. Such work machines have an operating device installed in the cab, but the running direction of the running body is based on the running body, regardless of the orientation of the upper rotating body. Therefore, the operating direction and the running direction do not match except when the upper rotating body is facing forward. Therefore, the operator must always be aware of the orientation of the running body and the upper rotating body when operating the operating device, which makes operation difficult and, in some cases, may cause the work machine to move in an unintended direction due to incorrect operation.

[0003] In response to this, Patent Document 1 describes a technique for informing the operator of the traveling direction so that the operator is made aware of an erroneous operation.

[0004] Furthermore, Patent Document 2 describes a technology that recognizes cliff edges as no-entry areas for driving and suppresses driving actions in a direction that would lead to entry into the no-entry areas. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 3394683 [Patent Document 2] Japanese Patent Application Publication No. 2019-173467 Summary of the Invention [Problem to be solved by the invention]

[0006] In Patent Document 1, the operator is notified of the travel direction so that they can stop the operation and be made aware of the erroneous travel operation, and the drive of the travel motor is delayed for a predetermined time when the upper rotating body travels in a range other than forward. However, there are cases where the upper rotating body travels backward, for example, when entering or leaving a parking area, and in this conventional technology, the drive of the travel motor is delayed for a predetermined time even in such cases, which can reduce workability.

[0007] On the other hand, Patent Document 2 recognizes no-entry areas (cliff edges) and restricts only travel operations in those directions, thereby solving the problem of Patent Document 1 by restricting erroneous operations that need to be restricted (entering no-entry areas). However, Patent Document 2 uses a distance sensor to recognize no-entry areas (cliff edges), and this distance sensor is placed on the upper rotating body. Therefore, for example, when a hydraulic excavator is loading earth and sand onto a dump truck and releasing the earth and sand at a height equivalent to that of the upper rotating body, the earth and sand may adhere to the distance sensor, which may result in a false detection.

[0008] The present invention was created in view of the above-described circumstances and with the aim of solving these problems, and has an object to provide a work machine that can suppress unintended operation of the work machine due to erroneous operation of the travel operation. [Means for solving the problem]

[0009] In order to solve the above-mentioned problems, the working machine of the present invention comprises a lower running body, an upper rotating body rotatably attached to the lower running body, a front working implement rotatably attached to the upper rotating body, an attitude detection device that detects the attitude of the front working implement, and a control device that controls the running operation of the lower running body and the swinging operation of the upper rotating body, wherein the control device comprises: a no-entry area determination unit that, when the front working implement is positioned below the lower running body by more than a predetermined amount, determines, from the detection result of the attitude detection device, a preset angle range that includes the swing angle of the upper rotating body relative to the lower running body at that time, as a no-entry area; a no-entry area storage unit that stores the no-entry area determined by the no-entry area determination unit; and a running operation control unit that restricts running operation in a direction approaching the no-entry area stored in the no-entry area storage unit. [Effects of the Invention]

[0010] The present invention can reduce the possibility of unintended operation of the work machine due to an erroneous operation when starting to travel.

[0011] Problems, configurations, and effects other than those described above will become apparent from the following description of the embodiments. [Brief explanation of the drawings]

[0012] [Figure 1] Diagram of a hydraulic excavator. [Figure 2] FIG. 2 is a diagram showing a controller for controlling a hydraulic excavator together with a hydraulic drive unit. [Figure 3] Detailed view of the solenoid valve unit. [Figure 4A] FIG. 2 is a side view showing a coordinate system in the hydraulic excavator of FIG. 1. [Figure 4B] FIG. 2 is a top view showing a coordinate system in the hydraulic excavator of FIG. 1. [Figure 5] FIG. 2 is a hardware configuration diagram of a controller according to the first embodiment. [Figure 6] FIG. 2 is a functional block diagram of a controller according to the first embodiment. [Figure 7] FIG. 4 is a diagram showing the relationship between the target control pressure of the electromagnetic proportional valve and the operation signal. [Figure 8] 7 is a control flowchart of the entry-prohibited area determination unit 710 in the first embodiment. [Figure 9] 6 is a control flowchart of a running start prevention determination unit 730 in the first embodiment. [Figure 10] FIG. 4 is a diagram showing an example of array data stored in a no-entry area storage unit 720 according to the first embodiment. [Figure 11] FIG. 10 is a diagram showing the determination method in S510 of FIG. 9 in the first embodiment. [Figure 12] FIG. 3 is a diagram showing an operation example of the first embodiment. [Figure 13] 10 is a control flowchart of a running start prevention determination unit 730 in the second embodiment. [Figure 14] FIG. 10 is a diagram showing an example of array data stored in a no-entry area storage unit 720 according to the second embodiment. [Figure 15] FIG. 10 is a diagram showing an operation example of the second embodiment. [Figure 16] FIG. 10 is a diagram showing a determination method in S510 of FIG. 9 according to the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In each drawing, parts having the same function are given the same reference numerals, and repeated description may be omitted. Note that, although the following describes an example of a hydraulic excavator equipped with a bucket 10 as a working implement (attachment) at the tip of a working device, the present invention can also be applied to hydraulic excavators equipped with working implements other than buckets, and to work machines other than hydraulic excavators.

[0014] In the following explanation of this paper, when there are multiple identical components, an alphabet may be added to the end of the reference number (number), but the alphabet may be omitted to refer to the multiple components collectively. For example, when there are two pumps 2a and 2b, they may be collectively referred to as pump 2.

[0015] [First embodiment] <Basic configuration> FIG. 1 is a configuration diagram of a hydraulic excavator according to a first embodiment of the present invention, FIG. 2 is a diagram showing a controller for the hydraulic excavator according to the first embodiment of the present invention together with a hydraulic drive system, and FIG. 3 is a detailed diagram of a solenoid valve unit 160 in FIG. 2.

[0016] 1, the hydraulic excavator 1 is made up of an articulated front working implement 1A and a vehicle body 1B. The vehicle body 1B comprises a lower traveling body 11 that travels using left and right traveling hydraulic motors 3a (FIGS. 2 and 3), 3b (right traveling hydraulic motor 3a, left traveling hydraulic motor 3b), and an upper rotating body 12 that is attached to the lower traveling body 11 and rotates using a swing hydraulic motor 4.

[0017] The front working mechanism 1A is configured by connecting a plurality of driven members (a boom 8, an arm 9, and a bucket 10) that each rotate in the vertical direction. The base end of the boom 8 is rotatably supported via a boom pin at the front of the upper rotating body 12. An arm 9 is rotatably connected to the tip of the boom 8 via an arm pin, and a bucket 10 is rotatably connected to the tip of the arm 9 via a bucket pin. The boom 8 is driven by a boom cylinder 5, the arm 9 is driven by an arm cylinder 6, and the bucket 10 is driven by a bucket cylinder 7.

[0018] A boom angle sensor 30 is attached to the boom pin, an arm angle sensor 31 to the arm pin, and a bucket angle sensor 32 to the bucket link 13 so that the rotation angles α, β, and γ (see FIG. 4A) of the boom 8, arm 9, and bucket 10 can be measured, and a vehicle body inclination angle sensor 33 is attached to the upper rotating body 12 to detect the inclination angle φ (see FIG. 4A) of the upper rotating body 12 (vehicle body 1B) relative to a reference plane (e.g., a horizontal plane). Note that angle sensors 30, 31, and 32 can each be replaced with an angle sensor relative to a reference plane (e.g., a horizontal plane).

[0019] A swing angle sensor 34 is attached to the swing center axis (also referred to as the swing axis) so that the relative angle θ (see FIGS. 4A and 4B) between the upper swing body 12 and the lower travel body 11 can be measured.

[0020] Installed within the operator's cab 120 provided in the upper rotating body 12 are a right travel lever 23a for operating the right travel hydraulic motor 3a (lower traveling body 11), a left travel lever 23b for operating the left travel hydraulic motor 3b (lower traveling body 11), a right operating lever 22a for operating the boom cylinder 5 (boom 8) and the bucket cylinder 7 (bucket 10), and a left operating lever 22b for operating the arm cylinder 6 (arm 9) and the swing hydraulic motor 4 (upper rotating body 12). Hereinafter, the right travel lever 23a, the left travel lever 23b, the right operating lever 22a, and the left operating lever 22b may be collectively referred to as operating devices 22, 23.

[0021] Also installed in the cab 120 are an engine speed setting device 480 for setting the engine speed, and a display device (e.g., a liquid crystal display) 53 capable of informing the operator of the traveling start inhibited state (details will be explained later).

[0022] As shown in FIG. 2, an engine 18, which is a prime mover mounted on the upper rotating body 12, drives hydraulic pumps 2a, 2b and a pilot pump 48. The hydraulic pumps 2a, 2b are variable displacement pumps whose displacements are controlled by regulators 2aa, 2ba, and the pilot pump 48 is a fixed displacement pump. The hydraulic pumps 2a, 2b and the pilot pump 48 draw hydraulic oil from a tank 200. In this embodiment, as shown in FIG. 2, a control signal output from a controller 40 is input to the regulators 2aa, 2ba. Although a detailed configuration of the regulators 2aa, 2ba is omitted, the discharge flow rates of the hydraulic pumps 2a, 2b are controlled in response to the control signal.

[0023] The pump line 143, which is the discharge pipe of the pilot pump 48, passes through the lock valve 39 and is then connected to each electromagnetic proportional valve in the solenoid valve unit 160. In this example, the lock valve 39 is a solenoid-operated directional control valve, and its electromagnetic driver is electrically connected to a position detector of a gate lock lever (not shown) located in the operator's cab 120 (FIG. 1). The position of the gate lock lever is detected by the position detector, and a signal corresponding to the position of the gate lock lever is input from the position detector to the lock valve 39. When the gate lock lever is in the locked position, the lock valve 39 closes and the pump line 143 is cut off, and when the gate lock lever is in the unlocked position, the lock valve 39 opens and the pump line 143 is opened. In other words, when the pump line 143 is cut off, operation by the operating devices 22 and 23 is disabled, and operations such as traveling, swinging, and excavation are prohibited.

[0024] The operating devices 22, 23 are of an electric lever type, and generate an electric signal corresponding to the amount and direction of operation by the operator. The electric signal thus generated is input to the control controller 40, which then outputs an electric signal to the solenoid valve unit 160 to drive the solenoid proportional valves 54-59 (see FIG. 3) corresponding to the operation input to the operating devices 22, 23. The solenoid proportional valves 54-59 supply the input electric signal to hydraulic actuators 150a-155b of the corresponding flow control valves 15a-15f via pilot lines 144a-149b, and the signal is used as a control signal to drive these flow control valves 15a-15f.

[0025] The operation device 22 is provided with a start prevention disabling operation device 670 (see FIGS. 5 and 6) for disabling the travel start prevention control described below. The start prevention disabling operation device 670 is configured, for example, by a momentary switch, and is electrically connected to the control controller 40. When pressed, it is energized, and when not pressed, it is cut off, thereby transmitting the operation state of the start prevention disabling operation device 670 to the control controller 40.

[0026] The pressure oil discharged from the hydraulic pump 2 is supplied via flow control valves 15a, 15b, 15c, 15d, 15e, and 15f to the right traveling hydraulic motor 3a, the left traveling hydraulic motor 3b, the swing hydraulic motor 4, the boom cylinder 5, the arm cylinder 6, and the bucket cylinder 7. The supplied pressure oil causes the boom cylinder 5, the arm cylinder 6, and the bucket cylinder 7 to extend and retract, thereby rotating the boom 8, the arm 9, and the bucket 10, respectively, changing the position and attitude of the bucket 10. The supplied pressure oil also rotates the swing hydraulic motor 4, causing the upper swing structure 12 to swing relative to the lower traveling structure 11. The supplied pressure oil then rotates the right traveling hydraulic motor 3a and the left traveling hydraulic motor 3b, causing the lower traveling structure 11 to travel.

[0027] Pressure sensors 16a to 16f and 16k to 16l are provided to the swing hydraulic motor 4, boom cylinder 5, arm cylinder 6, and bucket cylinder 7 so as to detect the actuator pressures. The pressure sensors 16a to 16f and 16k to 16l detect the pressures in the input and output lines of the swing hydraulic motor 4, and the pressures on the bottom and rod sides of the boom cylinder 5, arm cylinder 6, and bucket cylinder 7, respectively, and output them as electrical signals to the controller 40 (in FIG. 2, the connection lines from the pressure sensors 16a to 16f and 16k to 16l to the controller 40 are not shown due to space limitations).

[0028] Pressure sensors 16g to 16j are provided in the flow paths connecting the travel hydraulic motors 3a, 3b and the flow control valves 15e, 15f so that the actuator pressure of the travel hydraulic motors 3a, 3b can be detected. The pressure sensors 16g to 16j detect the pressure in the input / output lines of the travel hydraulic motors 3a, 3b, and output the result as an electric signal to the controller 40 (in FIG. 2, the connection lines from the pressure sensors 16g to 16j to the controller 40 are not shown due to space limitations).

[0029] The engine 18 is provided with an engine control controller 470 that controls the rotation speed and other parameters of the engine 18 in response to a control signal from the control controller 40. The engine 18 is provided with an engine rotation speed detection device 490, which is a rotation sensor for detecting the engine rotation speed.

[0030] <Solenoid valve unit 160> As shown in FIG. 3, the solenoid valve unit 160 has a primary port side connected to the pilot pump 48 via the pump line 143, and includes solenoid proportional valves 54a to 59b that reduce the pilot pressure from the pilot pump 48 and output it to the pilot lines 144a to 149b.

[0031] The pilot lines 144a to 149b are provided with pressure sensors 17a to 17l so as to detect the output pressures of the electromagnetic proportional valves 54a to 59b.

[0032] The electromagnetic proportional valves 54a to 59b have a minimum opening when not energized, and the opening increases as the current, which is a control signal from the controller 40, increases. In this way, the opening of each of the electromagnetic proportional valves 54a to 59b corresponds to the control signal from the controller 40.

[0033] The electromagnetic proportional valves 58a and 59a drive the traveling hydraulic motor 3 in the direction in which the undercarriage 11 moves forward, and the electromagnetic proportional valves 58b and 59b drive the traveling hydraulic motor 3 in the direction in which the undercarriage 11 moves backward.

[0034] In the solenoid valve unit 160 configured as described above, when a control signal is output from the control controller 40 to drive the solenoid proportional valves 54a to 59b, pilot pressure can be generated even when the corresponding operating devices 22, 23 are not operated by an operator, so that the operation of each actuator (3 to 7) can be forcibly generated.

[0035] <Controller 40> FIG. 5 is a configuration diagram of a system provided in a hydraulic excavator according to the first embodiment of the present invention.

[0036] The system of Figure 5 includes an attitude detection device 50, operation devices 22, 23, a start prevention disabling operation device 670 for disabling the travel start prevention control, pressure sensors 17g to 17j provided in the above-mentioned solenoid valve unit 160, an engine speed setting device 480 provided in the driver's cab 120 for setting the engine speed, a display device (e.g., a liquid crystal display) 53 also provided in the driver's cab 120 and capable of notifying the operator of the travel start prevention state, a control controller (control device) 40 which is a computer that manages control, an engine control controller 470 that controls the speed of the engine 18 etc. in accordance with control signals from the control controller 40, and electromagnetic proportional valves 54 to 59 that cause the operation of each actuator (3 to 7) in accordance with control signals from the control controller 40.

[0037] The posture detection device 50 is made up of a boom angle sensor 30, an arm angle sensor 31, a bucket angle sensor 32, a vehicle body inclination angle sensor 33, and a swing angle sensor 34. These angle sensors 30, 31, 32, 34 and the inclination angle sensor 33 function as posture sensors that detect the posture of the front working implement 1A.

[0038] The display device 53 receives an alert flag output by the controller 40 as an input, and when the alert flag is on, it alerts the operator of the travel start inhibited state, and when the alert flag is off, it cancels the alert of the travel start inhibited state. In this embodiment, the alerting means (device) for the operator is configured as a display device, but it may also be configured as an alerting means (device) that uses sound such as a buzzer.

[0039] 5, the controller 40 has an input unit 91, a central processing unit (CPU) 92 which is a processor, a read-only memory (ROM) 93 and a random access memory (RAM) 94 which are storage devices, and an output unit 95. The input unit 91 receives signals from the angle sensors 30-32, 34 and the tilt angle sensor 33 which are the attitude detection device 50, signals indicating the amount of operation from the operation devices 22, 23, a signal from the engine speed setting device 480, a signal from the start prevention disabling operation device 670, and signals from the pressure sensors 17g-17j, and converts these signals so that the CPU 92 can perform calculations. The ROM 93 is a recording medium that stores a control program for executing control content, including processing according to flowcharts described below, and various information necessary for executing the flowcharts. The CPU 92 performs predetermined calculations on the signals received from the input unit 91 and the memories (93, 94) in accordance with the control program stored in the ROM 93. The output unit 95 generates an output signal according to the calculation result in the CPU 92, and outputs the signal to the engine control controller 470 and the electromagnetic proportional valves 54 to 59, thereby driving and controlling the engine 18 and the hydraulic actuators (3 to 7).

[0040] Although the controller 40 in FIG. 5 includes semiconductor memories such as a ROM 93 and a RAM 94 as storage devices, any storage device can be substituted, and for example, a magnetic storage device such as a hard disk drive may be included.

[0041] 6 is a functional block diagram of the control controller 40. The control controller 40 includes an electromagnetic proportional valve control unit 44, a target motion calculation unit 700, an entry-prohibited area determination unit 710, an entry-prohibited area storage unit 720, a running start prevention determination unit 730, and an engine rotation speed setting unit (not shown).

[0042] An engine speed setting unit (not shown) sets a target engine speed based on a signal from engine speed setting device 480, and outputs a signal corresponding to the set target engine speed to engine controller 470.

[0043] The target operation calculation unit 700 calculates and outputs target control pressures for the electromagnetic proportional valves 54 to 59 corresponding to the operations of the operating devices 22 and 23 based on the operation signals output from the operating devices 22 and 23. Specifically, the calculation contents are set in advance as a table of target control pressures for the electromagnetic proportional valves corresponding to the operation signals as shown in Fig. 7, and the target control pressures for the electromagnetic proportional valves 54 to 59 are output in accordance with this.

[0044] The entry-prohibited area determination unit 710 determines an entry-prohibited area based on signals from the attitude detection device 50 and the pressure sensors 17g to 17j, and outputs the determination result to the entry-prohibited area storage unit 720. Details will be explained later in the control flowchart of the entry-prohibited area determination unit 710.

[0045] The entry-forbidden area storage unit 720 stores the determination result output by the entry-forbidden area determination unit 710. Details will be explained below in conjunction with the details of the entry-forbidden area determination unit 710 in a control flowchart for the entry-forbidden area determination unit 710.

[0046] The travel start prevention determination unit 730 determines whether or not to prevent (restrict) the start of travel based on the target control pressures of the electromagnetic proportional valves 58, 59 that drive the travel hydraulic motor 3 among the commands output by the target operation calculation unit 700, the signal from the start prevention disabling operation device 670, the signals from the pressure sensors 17g to 17j, and the data stored in the no-entry area storage unit 720, and outputs the target control pressures of the electromagnetic proportional valves 58, 59 that drive the travel hydraulic motor 3 to the electromagnetic proportional valve control unit 44, and outputs a signal indicating the travel start prevention state to the display device 53. Details will be explained later in the control flowchart of the travel start prevention determination unit 730.

[0047] The electromagnetic proportional valve control unit 44 outputs a control command value for the corresponding electromagnetic proportional valve in accordance with the electromagnetic proportional valve target control pressure output by the target operation calculation unit 700. However, for the electromagnetic proportional valves 58, 59 that drive the traveling hydraulic motor 3, it outputs a control command value in accordance with the output of the traveling start prevention determination unit 730. That is, in this embodiment, the traveling start prevention determination unit 730 and the electromagnetic proportional valve control unit 44 function as a traveling operation control unit that controls the driving of the traveling hydraulic motor 3 and controls the traveling operation of the vehicle body 1B (undercarriage 11).

[0048] <Control flowchart> 8 and 9 show control flowcharts of the entry-prohibited area determination unit 710 and the running start prevention determination unit 730 of the first embodiment.

[0049] The control flow chart of the entry-prohibited area determining unit 710 in FIG. 8 will be described.

[0050] In S400, it is determined whether or not the vehicle body 1B (undercarriage 11) is traveling based on signals detected by the pressure sensors 17g to 17j. Specifically, if the pressure values ​​detected by the pressure sensors 17g to 17j are greater than a predetermined pressure threshold, it is determined that the traveling hydraulic motor 3 is being driven and the vehicle body 1B (undercarriage 11) is traveling. The predetermined pressure threshold is set to a value at which it can be determined that the traveling hydraulic motor 3 is being driven. If it is determined that the vehicle body 1B (undercarriage 11) is traveling (in the case of YES), the process proceeds to S430, and if it is determined that the vehicle body 1B (undercarriage 11) is not traveling (in the case of NO), the process proceeds to S410.

[0051] In S410, it is determined whether the bucket 10 is below a predetermined value based on the signal detected by the attitude detection device 50. Specifically, the position Pz of the tip P on the Z axis is calculated from the angles α, β, and γ acquired from the attitude detection device 50 and the known length dimension values ​​L1, L2, and L3 (see FIG. 4A) between the connection pins of the boom 8, arm 9, bucket 10, and tip P. If this Pz is below L4, which indicates the length to the bottom end of the lower traveling structure 11, and the threshold value Lt, which determines the no-entry area, i.e., Pz<-(L4+Lt) (if YES), it is determined that the bucket 10 is below the predetermined value, i.e., the bucket 10 is in the no-entry area, and the process proceeds to S420. If the bucket 10 is above the predetermined value (Pz≧-(L4+Lt)) (if NO), the process ends. The threshold value Lt is set, for example, to a length corresponding to the step that the lower traveling structure 11 can travel over during normal traveling.

[0052] In S420, the relative angle θ of the upper swing structure 12 with respect to the undercarriage 11, detected by the attitude detection device 50, is linked to the determination result (step determination) in S410, and stored in the no-entry area storage unit 720. Specifically, as shown in FIG. 10 , the no-entry area storage unit 720 holds array data that can store determination results for each relative angle θ, and stores a 1 as the determination result of S410 in the array location for the corresponding relative angle θ. That is, the no-entry area storage unit 720 holds array data consisting of multiple array locations within a predetermined angle range, and the no-entry area determination unit 710 determines, as a no-entry area, the array location (of the relative angle θ) that corresponds to the relative angle θ when the bucket 10 is below the undercarriage 11 by more than a predetermined distance (Lt), and stores the determination result in the no-entry area storage unit 720 (by storing a 1 in the array location). FIG. 10 illustrates an example in which the relative angle θ is arranged in 10-degree increments; however, the array may be appropriately determined taking into consideration the size of the storage capacity, the accuracy of the swing angle sensor 34, and the like.

[0053] In S430, processing is performed when it is determined in S400 that the vehicle body 1B (undercarriage 11) is traveling, and the determination result (i.e., the link between the relative angle θ and the determination result (step determination)) in the no-entry area storage unit 720 is initialized. Specifically, all of the determination result fields in S410 in FIG. 10 are set to 0.

[0054] The control flow chart of the running start prevention determination unit 730 in FIG. 9 will be described.

[0055] In S500, the signal of the electromagnetic proportional valve target control pressure related to the traveling operation and the signals of the pressure sensors 17g to 17j are obtained from the output of the target operation calculation unit 700, and it is determined whether a traveling start operation has been performed. Specifically, the electromagnetic proportional valve target control pressure of the electromagnetic proportional valves 58, 59 that drive the traveling hydraulic motor 3 is obtained, and if it is greater than a predetermined threshold value (for example, 0) and if it is determined from the results of the pressure sensors 17g to 17j that the vehicle body 1B (undercarriage 11) is not currently traveling (same as S400), it is determined that a traveling start operation has been performed. If it is determined that a traveling start operation has been performed (YES), proceed to S510. If not (NO), proceed to S550.

[0056] In S510, it is determined whether the traveling direction is toward the no-entry area based on the array data in the no-entry area storage unit 720. Specifically, when it is assumed that the vehicle body 1B (undercarriage 11) will be driven in the forward direction based on the electromagnetic proportional valve target control pressures of the electromagnetic proportional valves 58, 59 that drive the traveling hydraulic motor 3, it is determined whether the no-entry area (the angle range for which the determination result in S410 is 1) stored in the no-entry area storage unit 720 is included in a range that suppresses a preset operation in the forward traveling direction (electromagnetic proportional valves 58a, 59a).If it is included, it is determined that the traveling direction is toward the no-entry area, and if it is not included, it is determined that the traveling direction is not toward the no-entry area. Similarly, if it is assumed that the vehicle body 1B (undercarriage 11) will be driven in the reverse direction, it is determined whether or not the pre-set range for suppressing operation in the reverse direction (electromagnetic proportional valves 58b, 59b) includes the no-entry area (the angle range for which the determination result of S410 is 1) stored in the no-entry area storage unit 720. If it does, it is determined that the traveling direction is toward the no-entry area, and if it does not, it is determined that the traveling direction is not toward the no-entry area. A detailed determination example will be described later. If the result of this determination is YES, proceed to S520, and if NO, proceed to S550.

[0057] In S520, a signal from the start-up prevention disable operation device 670 is acquired, and it is determined whether or not the start-up prevention disable operation device 670 has been operated (depressed). If the operation has been performed (YES), the process proceeds to S550, and if the operation has not been performed (NO), the process proceeds to S530.

[0058] In S530, the electromagnetic proportional valve target control pressures of the electromagnetic proportional valves 58, 59 are set to 0, and the electromagnetic proportional valve target control pressures of the electromagnetic proportional valves 58, 59 are output to the electromagnetic proportional valve control unit 44. As a result, driving of the traveling hydraulic motor 3 by the electromagnetic proportional valves 58, 59 is suppressed, thereby suppressing (restricting) the start of traveling, and restricting (prohibiting) traveling operation in a direction approaching the area (angle range) determined to be the entry prohibition area stored in the entry prohibition area storage unit 720. In addition, the process proceeds to S540, where the notification flag is turned on, and the notification flag (on) is output to the display device 53. As a result, the operator is notified that the traveling start suppressed state (travel start suppressed) is in progress.

[0059] In S550, the electromagnetic proportional valve target control pressures of the electromagnetic proportional valves 58, 59 are output at the same value (target control pressure corresponding to the operation amount) as the output value of the target motion calculation unit 700. As a result, the travel target speed corresponding to the operation amount of the operation device 23 is realized. Also, the process proceeds to S560, where the notification flag is turned off and the notification flag (off) is output to the display device 53. As a result, the notification to the operator of the travel start inhibited state is canceled.

[0060] The method of determining whether the traveling direction is the direction of the no-entry area (S510 in FIG. 9) in this embodiment will be described with reference to FIG.

[0061] As shown in Fig. 11, a range in which the traveling operation is suppressed is set in advance for the relative angle θ determined to be within the no-entry region. In the embodiment of Fig. 11, the range of θf1 (>0) to θf2 (<0) is the range in which the operation in the forward traveling direction (electromagnetic proportional valves 58a, 59a) is suppressed, and the ranges of θr1 (>0) to 180 degrees and θr2 (<0) to -180 degrees are the ranges in which the operation in the reverse traveling direction (electromagnetic proportional valves 58b, 59b) is suppressed.

[0062] Here, by referring to the data stored in the no-entry area memory unit 720, if the relative angle (range) for which the judgment result of S410 is 1 is included in the range in which this running operation is suppressed, it is determined that the running direction is in the direction of the no-entry area.

[0063] <Actions and Effects> An example of operation will be described below with reference to FIG.

[0064] Figure 12 shows an example in which slope excavation is performed with a turning angle θ of 0 degrees (top of the figure), and then the robot turns 180 degrees (turning angle θ is 180 degrees) and attempts to travel in a direction away from the slope (bottom of the figure).

[0065] In the state shown in the upper part of Fig. 12, the vehicle is not traveling (S400), and the tip P of the bucket 10 is positioned lower than a predetermined value, so the area is determined to be a no-entry area (S410). Therefore, in the no-entry area storage unit 720, a 1 is stored in the array corresponding to the swing angle θ = 0 degrees as shown in Fig. 10 (S420).

[0066] After that, the vehicle turns 180 degrees and starts moving. At this time, the following two patterns (1) and (2) will be explained.

[0067] (1) When driving forward The forward travel operation is a direction toward the slope (the lower travel structure 11 is not turning), so it is an erroneous operation and does not correspond to the actual direction of travel. The operation at this time will be described with reference to the control flowchart of FIG.

[0068] Since no traveling operation is being performed, the solenoid proportional valves 58, 59 are not open. Therefore, the pressure sensors 17g to 17j detect 0, and since a forward traveling operation is being performed, the target control pressure of the solenoid proportional valves 58a, 59a is generated according to the amount of operation of the traveling lever (operating device) 23 as shown in Figure 7, and therefore, a traveling start operation is determined in S500.

[0069] In S510, the no-entry area memory unit 720 is referenced and it is recognized that a no-entry area has been determined to exist in an area between 0 degrees and 10 degrees. Furthermore, since a forward driving operation is being performed, the area determined to contain a no-entry area is included in the range in which the forward driving movement in Figure 11 is determined to be a direction toward the no-entry area, so it is determined that the driving direction is in the direction of the no-entry area and the process proceeds to S520.

[0070] In S520, since the start-up prevention disabling operation has not been performed, the process proceeds to S530.

[0071] In S530, the target control pressures of the electromagnetic proportional valves 58 and 59 are set to zero.

[0072] In S540, the notification flag is turned on, and the display device 53 displays that the vehicle is in the travel start inhibited state (travel start inhibited).

[0073] In other words, the vehicle will not travel in a direction toward the slope.

[0074] (2) When reverse driving is performed The reverse operation is in the direction away from the slope (the lower traveling structure 11 is not turning), so this is the direction in which the user actually wants to travel. The operation at this time will be described with reference to the control flowchart of FIG.

[0075] Since no traveling operation is being performed, the solenoid proportional valves 58, 59 are not open. Therefore, the pressure sensors 17g to 17j detect 0, and since a reverse traveling operation is being performed, the target control pressure of the solenoid proportional valves 58b, 59b is generated according to the amount of operation of the traveling lever (operating device) 23 as shown in Figure 7, and therefore, a determination is made in S500 that a traveling start operation has been performed.

[0076] In S510, the no-entry area memory unit 720 is referenced and it is recognized that a no-entry area has been determined to exist in an area between 0 degrees and 10 degrees. Furthermore, since a reverse driving operation is being performed, the area determined to be a no-entry area is not included in the range in which the reverse driving operation in Figure 11 is determined to be a direction toward the no-entry area, so it is determined that the driving direction is not a direction approaching the no-entry area, and the process proceeds to S550.

[0077] In S550, the target control pressures (target control pressures corresponding to the manipulated variables) of the solenoid proportional valves 58, 59, which are output values ​​from the target operation calculation unit 700, are output as they are.

[0078] In S560, the notification flag is turned off, so that the vehicle start inhibit state is not notified.

[0079] That is, depending on the operation, the vehicle can travel in a direction away from the slope.

[0080] Since the vehicle has traveled, the determination result of the no-entry area storage unit 720 is erased (initialized) in S430 of Fig. 8. As a result, even if the operation is switched to forward travel during travel, the vehicle can travel (for example, travel in a direction toward a slope).

[0081] Next, we will explain the case in the upper part of Figure 12 where, in the middle of excavation, in other words, in a state where a no-entry area determination has been made in S420 with a swing angle of 0 degrees or more and less than 10 degrees, as in (1) and (2), the bucket 10 has not reached the back of the excavation area, and you want to travel in a direction slightly closer to the slope.

[0082] (3) If the forward driving operation is continued As in (1), running motion is suppressed.

[0083] (4) When driving forward with the start suppression disabled Up to S510 it is the same as (1).

[0084] Since the start-up prevention disable operation has been performed in S520, the process proceeds to S550.

[0085] In S550, the target control pressures (target control pressures corresponding to the manipulated variables) of the solenoid proportional valves 58, 59, which are output values ​​from the target operation calculation unit 700, are output as they are.

[0086] That is, depending on the operation, the vehicle travels in a direction toward the slope.

[0087] As described above, the hydraulic excavator (work machine) 1 of this embodiment comprises a lower traveling body 11, an upper rotating body 12 rotatably attached to the lower traveling body 11, a front working mechanism 1A rotatably attached to the upper rotating body 12, an attitude detection device 50 that detects the attitude of the front working mechanism 1A, and a control controller (control device) 40 that controls the traveling operation of the lower traveling body 11 and the swinging operation of the upper rotating body 12, and the control controller (control device) 40 determines the attitude of the front working mechanism 1A from the detection results of the attitude detection device 50. The device is equipped with an entry-prohibited area determination unit 710 that, when the working device 1A (the bucket 10 thereof) is positioned below the lower running body 11 by a predetermined distance, determines a preset angle range including the rotation angle of the upper rotating body 12 relative to the lower running body 11 at that time as a entry-prohibited area, an entry-prohibited area memory unit 720 that stores the entry-prohibited area determined by the entry-prohibited area determination unit 710, and a traveling operation control unit (730, 44) that restricts traveling operation in a direction approaching the entry-prohibited area (angle range) stored in the entry-prohibited area memory unit 720.

[0088] In addition, the driving operation control unit determines whether the no-entry area stored in the no-entry area memory unit 720 is included in a range in which a driving operation that has been preset to be restricted in response to forward driving operation or reverse driving operation due to driving operation is suppressed, and if the no-entry area is included in the range, it determines that the driving direction is in the direction of the no-entry area and restricts driving operation in a direction approaching the no-entry area.

[0089] The vehicle also includes a disabling operation device for disabling the restriction on the traveling operation (travel start prevention control), and the traveling operation control unit disables the restriction on the traveling operation according to the operation state of the disabling operation device.

[0090] The vehicle is also provided with an alarm device for notifying the operator of the restricted state of the traveling operation (travel start inhibited state), and the traveling operation control unit notifies the operator via the alarm device that the traveling operation is being restricted (travel start inhibited) while the traveling operation is being restricted.

[0091] Furthermore, when the no-entry area determination unit 710 determines that the hydraulic excavator (work machine) 1 is not traveling, it determines whether the area is a no-entry area and stores the determination result in the no-entry area storage unit 720, and when it determines that the hydraulic excavator (work machine) 1 is traveling, it initializes the determination result stored in the no-entry area storage unit 720.

[0092] That is, when the front working implement 1A (the bucket 10 thereof) passes below the lower running structure 11 by a predetermined distance, the control controller (control device) 40 of the hydraulic excavator (work machine) 1 of this embodiment stores the relative angle between the upper rotating structure 12 and the lower running structure 11 at that time, sets this as a no-entry area, and suppresses the traveling operation when a traveling operation into the no-entry area is performed.

[0093] In the hydraulic excavator 1 configured as described above, unintended operation of the work machine due to erroneous operation of the traveling operation can be suppressed.

[0094] [Second embodiment] The second embodiment will be described with reference to Figures 13 to 15. In the second embodiment, although digging is performed as in trench digging work, there are situations where the trench width is narrow and travelable, and an embodiment that can cope with such situations will be described.

[0095] In the second embodiment, unlike the control flowchart of the running start prevention determination unit 730 in FIG. 9 of the first embodiment, as shown in FIG. 13, a determination in S515 is performed between S510 and S520.

[0096] In S515, it is determined whether the work is trench digging. If it is determined that the work is trench digging, the process proceeds to S550, and if it is determined that the work is not trench digging, the process proceeds to S520.

[0097] An example of a method for determining whether the work in S515 of FIG. 13 is trench digging will be described.

[0098] When trench digging work as shown in FIG. 15 is performed, the determination result in S410 is 1 only when the upper rotating body 12 faces forward relative to the lower traveling body 11 as shown in FIG. 14 (for example, the relative angle θ corresponds to -5 degrees to 5 degrees in FIG. 14). That is, it is determined that trench digging is being performed when the determination result in S410 is 1 only for the arrangement location corresponding to when the upper rotating body 12 faces forward relative to the lower traveling body 11. In other words, if the entry-prohibited area (the angle range for which the determination result in S410 is 1) stored in the entry-prohibited area storage unit 720 is made up only of a preset entry-permitted area (for example, the relative angle θ corresponds to -5 degrees to 5 degrees in FIG. 14), it is determined that trench digging is being performed, and traveling operation in a direction approaching the area determined to be the entry-prohibited area stored in the entry-prohibited area storage unit 720 is permitted (in other words, traveling operation is not restricted).

[0099] The array configuration of the array data in Fig. 14 is an example, and may be different from or the same as Fig. 10 of the first embodiment, as in Fig. 14. For example, when the array configuration of the array data is the same as Fig. 10 of the first embodiment, one or more array locations of relative angles θ in the array data can be set as an entry-permitted area, and when the determination result of S410 for multiple array locations other than the entry-permitted area is 1 (stored), the angle range corresponding to those array locations can be set as an entry-prohibited area.

[0100] <Actions and Effects> As described above, the traveling operation control unit of the hydraulic excavator (work machine) 1 of this embodiment permits traveling operation in a direction approaching the no-entry area (angle range) stored in the no-entry area storage unit 720 when the no-entry area stored in the no-entry area storage unit 720 is made up of only predetermined allowed entry areas.

[0101] In this case, when travel is possible even in the direction of excavation, such as in trench digging work in Figure 15, travel start is permitted (travel start is not inhibited), and deterioration of workability due to the functioning of travel start inhibition control can be inhibited.

[0102] In the hydraulic excavator 1 configured as described above, unintended operation of the work machine due to erroneous operation of the travel operation can be suppressed, similar to the first embodiment.

[0103] [Third embodiment] The third embodiment will be described with reference to FIG.

[0104] In the third embodiment, the method of determining whether the traveling direction is toward the no-entry area in S510 in FIG. 9 is different from that in the first embodiment.

[0105] 16, a vector Vt representing the traveling direction of the vehicle body 1B (undercarriage 11) is calculated from the target control pressures of the electromagnetic proportional valves 58, 59 output from the target motion calculation unit 700. This may be done by calculating the traveling direction in relation to the output pressures of the electromagnetic proportional valves 58, 59 in advance through simulations or experiments and storing the data as table data, or by calculating dynamically by estimating the rotational speed of the traveling hydraulic motor 3 driven by the electromagnetic proportional valves 58, 59.

[0106] Next, from among the angle ranges determined to be no-entry areas stored in the no-entry area storage unit 720, the angle range closest to Vt is extracted, and the angle difference θd from Vt is calculated.

[0107] If this difference θd is smaller than a predetermined threshold θt, it is determined that the vehicle is traveling in the direction of the no-entry area, and if this difference θd is larger than the predetermined threshold θt, it is determined that the vehicle is not traveling in the direction of the no-entry area.

[0108] <Actions and Effects> As described above, the travel operation control unit of the hydraulic excavator (work machine) 1 of this embodiment calculates the difference in angle between the travel direction due to travel operation and the no-entry area stored in the no-entry area memory unit 720, and if the angle difference is smaller than a predetermined threshold, it determines that the travel direction is toward the no-entry area, and restricts travel operation in a direction approaching the no-entry area (angle range) stored in the no-entry area memory unit 720.

[0109] In this case, the determination method of Fig. 11 in the first embodiment is replaced with the determination method of Fig. 16, making it possible to control the operation of the work machine more precisely. Other operations are the same as in the first embodiment.

[0110] In the hydraulic excavator 1 configured as described above, unintended operation of the work machine due to erroneous operation of the travel operation can be suppressed, similar to the first embodiment.

[0111] In the first to third embodiments described above, angle sensors are used to detect the angles of the boom 8, arm 9, and bucket 10, but posture information of the hydraulic excavator 1 may be calculated using a cylinder stroke sensor instead of an angle sensor. Also, although an electric lever type hydraulic excavator 1 has been described as an example, in the case of a hydraulic pilot type excavator, a configuration may be adopted in which a command pilot pressure generated from the hydraulic pilot is controlled.

[0112] The components of the controller 40, as well as their functions and execution processes, may be partially or entirely implemented by hardware (for example, by designing logic for executing each function as an integrated circuit). The components of the controller 40 may also be implemented as a program (software) that is read and executed by an arithmetic processing device (for example, a CPU) to implement the functions of the controller 40. Information related to the program may be stored in, for example, a semiconductor memory (flash memory, SSD, etc.), a magnetic storage device (hard disk drive, etc.), or a recording medium (magnetic disk, optical disk, etc.).

[0113] In the first to third embodiments described above, the target control pressure of the electromagnetic proportional valve is limited, but it may also be configured to limit the operation signal, which is an input signal, or to reduce the engine speed.

[0114] The present invention is not limited to the above-described embodiments and includes various modifications. For example, the above-described embodiments have been described in detail to clearly explain the present invention, and are not necessarily limited to those including all of the described configurations. Furthermore, it is possible to replace part of the configuration of one embodiment with the configuration of another embodiment, or to add the configuration of another embodiment to the configuration of one embodiment. Furthermore, it is possible to add, delete, or replace part of the configuration of each embodiment with other configurations. [Explanation of symbols]

[0115] 1... Hydraulic excavator (work machine) 1A...Front work device 1B...Body 8...Boom 9...Arm 10...Bucket 11...Undercarriage 12...Upper rotating body 16a~16l...Pressure sensor 17a~17l...Pressure sensor 22, 23...Operating device 30...Boom angle sensor 31...Arm angle sensor 32...Bucket angle sensor 33...Vehicle body tilt angle sensor 34...Rotation angle sensor 40...Controller (control device) 44...Electromagnetic proportional valve control section (travel operation control section) 50...Attitude detection device 53...Display device (alarm device) 54, 55, 56, 57, 58, 59...Electromagnetic proportional valve 470...Engine control controller 480...Engine RPM setting device 670...Start-up suppression disable operation device 700...Target movement calculation unit 710...Prohibited area determination unit 720…Prohibited area storage unit 730...Travel start prevention determination unit (travel operation control unit)

Claims

1. a lower running body; an upper rotating body rotatably attached to the lower traveling body; a front working implement rotatably attached to the upper rotating body; a posture detection device that detects the posture of the front working implement; a control device for controlling the traveling operation of the lower traveling body and the rotating operation of the upper rotating body, The control device a no-entry zone determining unit that, when the front working implement is positioned lower than a predetermined amount from the lower traveling structure based on the detection result of the attitude detection device, determines a preset angle range that includes a swing angle of the upper rotating structure relative to the lower traveling structure at that time as a no-entry zone; a no-entry area storage unit that stores the no-entry area determined by the no-entry area determination unit; a travel operation control unit that limits travel operation in a direction approaching the no-entry area stored in the no-entry area storage unit.

2. 2. The work machine according to claim 1, the travel operation control unit determines whether the no-entry area stored in the no-entry area memory unit is included in a range in which a predetermined travel operation is to be restricted corresponding to a forward travel operation or a reverse travel operation due to a travel operation, and if the no-entry area is included in the range, determines that the travel direction is toward the no-entry area, and restricts travel operation in a direction approaching the no-entry area.

3. 2. The work machine according to claim 1, the travel operation control unit calculates the difference in angle between the travel direction due to travel operation and the no-entry area stored in the no-entry area storage unit, and if the angle difference is smaller than a predetermined threshold, determines that the travel direction is toward the no-entry area, and restricts travel operation in a direction approaching the no-entry area stored in the no-entry area storage unit.

4. 2. The work machine according to claim 1, the traveling operation control unit permits traveling in a direction approaching the no-entry area stored in the no-entry area storage unit when the no-entry area stored in the no-entry area storage unit is made up only of predetermined allowed areas.

5. 2. The work machine according to claim 1, the work machine is equipped with a disabling operation device for disabling the restriction on the traveling operation, The working machine is characterized in that the travel operation control unit disables the restriction on the travel operation in accordance with the operation state of the disabling operation device.

6. 2. The work machine according to claim 1, The work machine is equipped with an alarm device for notifying that the traveling operation is restricted, The work machine, wherein the traveling operation control unit notifies an operator via the notification device that the traveling operation is being restricted while the traveling operation is being restricted.

7. 2. The work machine according to claim 1, a no-entry area determination unit that, when it determines that the work machine is not traveling, determines whether the work machine is in a no-entry area and stores the determination result in the no-entry area storage unit, and that, when it determines that the work machine is traveling, initializes the determination result stored in the no-entry area storage unit.

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