Construction machine

Abstract

This construction machine comprises: a vehicle body; a driver cab that is provided to the vehicle body and that is boarded by an operator; a surrounding detection device that is provided to the vehicle body and that detects an obstacle around the vehicle body; a warning device that is provided to the driver cab; and a control device that arouses attention through the warning device in the case where the surrounding detection device detects an obstacle within a preset detection range. The construction machine is provided with an operation state switching device that switches the construction machine between an operable state and an inoperable state. The control device sets, when the state is switched to the operable state by the operation state switching device, a first range which has been prescribed around the vehicle body as the detection range, and sets, when the state is switched to the inoperable state by the operation state switching device, a second range which is around the vehicle body and has been prescribed at least partially smaller than the first range as the detection range. Accordingly, the operator can be informed of the existence of surrounding obstacles, while unnecessary warnings during the inoperable state are reduced.

Description

Construction machinery

[0001] The present invention relates to a construction machine.

[0002] In order to prevent collision accidents, some construction machines such as hydraulic excavators detect obstacles such as people or objects around the machine and alert the operator of the machine to their presence. For example, the system described in Patent Document 1 is known.

[0003] Patent Document 1 discloses a surroundings monitoring device for a work machine that is equipped with an alarm output unit that outputs an alarm to an operator, and that has a work machine state determination means that determines the state of the work machine, a person presence determination means that determines whether or not a person is present around the work machine, and an alarm control means that controls the alarm output unit, and the alarm control means outputs an alarm when it is determined that the work machine is not in a state where it is possible to work and that a person is present around the work machine, and then when it is determined that the work machine is in a state where it is possible to work.

[0004] JP 2014-181509 A

[0005] In the above-described conventional technology, when a construction machine detects a worker in the vicinity while in a disabled state, the alarm is stopped, and a new alarm is output when the construction machine returns to a enabled state, where it is operable. However, if the operator of the construction machine starts operating the machine immediately after it becomes enabled, there is a delay between the output of the alarm and the operation to stop the construction machine, which raises concerns that the detection of a worker in the vicinity of the construction machine and the alarm may not be fully realized. On the other hand, since the construction machine does not operate in a disabled state, there is little need to output an alarm to the operator even if a worker is present in the vicinity, and the operator may find the alarm annoying. In particular, when a worker near the vehicle body approaches the operator in the cab and has a conversation with him, the operator has switched to the disabled state and is aware of the worker's presence, so there is even less need to output an alarm to the operator, and the operator may find the alarm even more annoying.

[0006] The present invention has been made in consideration of the above, and aims to provide a construction machine that can notify the operator of the presence of surrounding obstacles while suppressing unnecessary alarms when work is not possible.

[0007] The present application includes multiple means for solving the above-mentioned problems, and one example thereof is a construction machine comprising: a vehicle body; a driver's cab provided on the vehicle body and in which an operator sits; a surroundings detection device provided on the vehicle body for detecting obstacles around the vehicle body; an alarm device provided in the driver's cab; and a control device that issues a warning using the alarm device when the surroundings detection device detects an obstacle within a predetermined detection range; the construction machine is further provided with a work state switching device that switches the construction machine between a workable state and an unworkable state; and when the control device is switched to the workable state by the work state switching device, the control device sets a first range that is predetermined around the vehicle body as the detection range, and when the control device is switched to the unworkable state by the work state switching device, the control device sets a second range that is predetermined to be smaller than the first range as the detection range around the vehicle body.

[0008] According to the present invention, it is possible to notify the operator of the presence of an obstacle in the vicinity while suppressing unnecessary alarms in a state where work is not possible.

[0009] Fig. 1 is a diagram showing an outline of the configuration of a hydraulic excavator, which is an example of a construction machine; Fig. 2 is a functional block diagram showing functional units relating to periphery detection among the processing functions of a controller, together with related configurations; Fig. 3 is a diagram showing an example of defining a detection range; Fig. 4 is a diagram showing another example of defining a detection range; Fig. 5 is a diagram showing another example of defining a detection range; Fig. 6 is a flowchart showing the contents of periphery detection processing according to a first embodiment; Fig. 7 is a flowchart showing the contents of periphery detection processing according to a third embodiment;

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following description, a hydraulic excavator will be shown as an example of a construction machine, but the present invention can also be applied to other construction machines such as a dump truck or a wheel loader.

[0011] First Embodiment A first embodiment of the present invention will be described with reference to FIGS. 1 to 4. FIG.

[0012] Fig. 1 is a diagram showing a schematic configuration of a hydraulic excavator, which is an example of a construction machine according to this embodiment. Fig. 2 is a functional block diagram showing a functional unit related to periphery detection, among the processing functions of a controller (control device), together with related configurations.

[0013] As shown in FIG. 1 , a hydraulic excavator 100, which is a construction machine, includes a crawler-type lower traveling body 3 and an upper rotating body 1 that is rotatably attached to the upper part of the lower traveling body 3 and that, together with the lower traveling body 3, constitutes the vehicle body (hereinafter also referred to as the vehicle body) of the construction machine.

[0014] The lower traveling structure 3 is driven by left and right traveling hydraulic motors 3 a, 3 b (only one of which is shown in FIG. 1 , and the reference number for the other is shown in parentheses). The upper rotating structure 1 is driven by torque generated by a swing hydraulic motor (not shown) and swings left and right relative to the lower traveling structure 3.

[0015] An operator's cab 4, in which an operator sits, is installed on one front side (e.g., left side) of the upper rotating body 1, and an articulated front working mechanism 2, which is used to create target terrain, etc., is attached to the side (e.g., right side) of the operator's cab 4 at the front of the upper rotating body 1. The direction in which the front working mechanism 2 of the upper rotating body 1 is installed is defined as the front of the vehicle body.

[0016] The front working mechanism 2 is configured by connecting a boom 2a, an arm 2b, and a bucket 2c, each of which rotates vertically, and is driven by a boom cylinder 2d, an arm cylinder 2e, and a bucket cylinder 2f, respectively.

[0017] Cameras 5a, 5b, and 5c for capturing images in each direction are installed as perimeter detection devices at the center, right side, and left side of the rear of the upper rotating body 1. Note that instead of cameras, the perimeter detection devices may be configured to use a LiDAR (Light Detection and Ranging) system that detects the position and properties of an object by irradiating it with a laser, or a system that detects an RFID (Radio Frequency Identification) tag worn by a worker to identify the position and identity of the worker.

[0018] The operator's cab 4 is equipped with an operation lever (not shown) for generating operation signals (pilot pressure in the case of a hydraulic drive system) for driving the boom cylinder 2d, arm cylinder 2e, bucket cylinder 2f, swing hydraulic motor (not shown), and traveling hydraulic motors 3a and 3b according to the operation direction and operation amount, and for operating the boom 2a, arm 2b, bucket 2c, upper swing body 1, and lower traveling body 3 according to the operation signals, and an alarm device 1 such as a buzzer for notifying the operator in the operator's cab 4 that an obstacle such as a person or object has been detected around the hydraulic excavator 100. 02, a touch panel monitor 103 having a function of displaying various information to the operator (including a function as an alarm device / alarm device that notifies the operator of the detection of an obstacle) and a function of inputting various settings by the operator, a work state switching device 101 (for example, a gate lock lever that switches between enabling and disabling an operation signal output from an operation lever) that selectively switches the work state of the hydraulic excavator 100 between a workable state in which the hydraulic excavator 100 is operable and an unworkable state in which the hydraulic excavator 100 is not operable, and a controller (control device) 110 that controls the overall operation of the hydraulic excavator 100.

[0019] In this embodiment, in which a hydraulic excavator 100 is used as an example of construction machinery, a gate lock lever is shown as the work state switching device 101. However, in the case of other construction machinery such as a dump truck or a wheel loader, a shift lever, a side brake, or the like corresponds to the work state switching device.

[0020] As shown in FIG. 2 , the controller 110 includes a detection range determination unit 111 and an alarm control unit 112 .

[0021] When the work state switching device 101 is switched to a workable state, the detection range determination unit 111 sets the detection range to a first range 121 that is predefined around the vehicle body, and when the work state switching device 101 is switched to a work-unavailable state, the detection range determination unit 111 sets the detection range to second ranges 122a, 122b, 122c that are predefined around the vehicle body (see Figure 3).

[0022] 3A to 3C are diagrams showing examples of defining the detection range.

[0023] As shown in Figures 3A to 3C, around the vehicle body of the hydraulic excavator 100, there are defined a first range 121 that is arranged to surround the vehicle body, and second ranges 122a, 122b, and 122c that are arranged so that at least a portion of them is narrower (smaller) than the first range 121.

[0024] The first range 121 is a range that is defined based on the reachable range of the structure of the hydraulic excavator 100 including the front working implement 2 during operations (excavation, swinging, and traveling) in a workable state, and is a range within which the operator should be alerted (warned) to the presence of an obstacle such as a worker. The second ranges 122a, 122b, and 122c are ranges that are defined based on the reachable range of the upper rotating body 1 during operations (swinging) immediately after switching from a non-workable state to a workable state, and are set to be narrower than the first range 121 in at least a portion of the interior thereof, and are ranges within which the operator should be alerted (warned) to the presence of an obstacle such as a worker. In addition, the second ranges 122a, 122b, 122c have narrow sections 123a, 123b, 123c defined in which the range on the driver's cab 4 side (i.e., the left side), which is positioned to one side (e.g., the left side) of the vehicle body, is narrower (smaller) than the ranges in other directions.

[0025] 3A , a first range 121 is defined around the vehicle body of the hydraulic excavator 100, and a second range 122a is defined at a position closer to the vehicle body than the first range 121. The second range 122a is defined so as to be smaller than the first range 121 around the vehicle body (here, the left and right sides and the rear). Furthermore, a narrow portion 123a is defined in the second range 122a on the side of the operator's cab 4, which is disposed biased to the left side of the vehicle body, i.e., in the left front direction, so as to be narrower (smaller) than the ranges in other directions.

[0026] 3B , a first range 121 is defined around the vehicle body of the hydraulic excavator 100, and a narrow portion 123b is arranged to the side of the operator's cab 4, which is positioned biased to the left side of the vehicle body, i.e., in the left front direction, to define a second range 122b that is narrower (smaller) than the first range 121. Note that the boundary between the first range 121 and the second range 122b is common to the areas other than the narrow portion 123b. In this way, the second range 122b is not limited to being smaller than the first range 121 over the entire circumference of the vehicle body (i.e., defined as in FIG. 3A ).

[0027] In the example shown in FIG. 3C , a first range 121 is defined around the vehicle body of the hydraulic excavator 100, and a second range 122c is defined at a position closer to the vehicle body than the first range 121. The second range 122c is defined so as to be smaller than the first range 121 around the vehicle body (here, the left and right sides and rear). The second range 122c also has a narrow portion 123c defined on the left side of the cab 4 of the vehicle body that is particularly narrower than the ranges in other directions. In other words, the boundary between the side of the vehicle body and the second range 122c coincides with the boundary between the second range 122c and the vehicle body, and the second range 122c is defined so that no detection range exists in the narrow portion 123c on the left side of the cab 4. In this way, the second range 122c is not limited to a detection range remaining in a predetermined direction (the left side of the cab of the vehicle body) (i.e., as defined in FIG. 3A ).

[0028] The alarm control unit 112 issues a warning (alert) to the operator via the alarm device when the surrounding detection devices 5a, 5b, 5c detect a worker (obstacle) within the detection range set by the detection range determination unit. For example, when the work state switching device 101 is switched to the work possible state, the alarm control unit 112 issues a warning (alert) to the operator of the cab 4 via the alarm device 102 when an obstacle such as a worker is detected within the detection range that is the first range 121. Furthermore, when the work state switching device 101 is switched to the work impossible state, the alarm control unit 112 issues a warning (alert) to the operator of the cab 4 via the alarm device 102 when an obstacle such as a worker is detected within the detection range that is the second range 122a, 122b, 122c.

[0029] FIG. 4 is a flowchart showing the contents of the surrounding detection process.

[0030] In FIG. 4 , the controller 110 determines whether the hydraulic excavator 100 is in a workable state, i.e., whether the work state switching device 101 has been switched to a workable state (step S100), and if the determination result is YES, sets the detection range for the workable state, i.e., the first range 121, as the detection range (step S110).

[0031] Also, if the judgment result in step S100 is NO, that is, if the work state switching device 101 is switched to a work-unavailable state, the detection range for the work-unavailable state, that is, the second ranges 122a, 122b, and 122c, are set as the detection range (step S111).

[0032] After the process of setting the detection range (steps S110, S111) is completed, it is next determined whether or not there is a detection target within the set detection range (step S120). If the determination result is YES, the alarm device 102 issues a warning to the operator of the cab 4 (step S130), and the process returns to step S100.

[0033] If the determination result in step S120 is NO, that is, if there is no target within the detection range, the process returns to step S100 without issuing a warning to the operator.

[0034] The effects of the present embodiment configured as above will be described.

[0035] In conventional technology, when a construction machine detects a worker in the vicinity while in a disabled state, the alarm is stopped, and an alarm is output again when the construction machine returns to a enabled state, where it is operable. However, in such cases, if the operator of the construction machine begins operating the machine immediately after it becomes operable, there is a delay between the output of the alarm and the operation to stop the construction machine, which raises concerns that the detection of a worker in the vicinity of the construction machine and the output of the alarm may not be fully realized. On the other hand, since the construction machine does not operate in a disabled state, there is little need to output an alarm to the operator even if a worker is present in the vicinity, and the operator may find the alarm annoying. In particular, when a worker near the vehicle body approaches the operator in the cab and starts a conversation, the operator has switched to the disabled state and is aware of the worker's presence, so there is less need to output an alarm to the operator, and the operator may find the alarm even more annoying.

[0036] In contrast to this, in the present embodiment, the work state switching device 101 selectively switches the work state of a construction machine (for example, a hydraulic excavator 100) between a workable state in which the machine is operable and an unworkable state in which the machine is not operable. When the work state switching device 101 is switched to the workable state, it sets the detection range to a first range 121 that is predefined around the vehicle body, and when the work state switching device 101 is switched to the unworkable state, it sets the detection range to second ranges 122a, 122b, 122c that are defined so that at least a portion of them is narrower than the first range 121. This makes it possible to notify the operator of the presence of obstacles in the surrounding area while suppressing unnecessary alarms in the unworkable state.

[0037] Second Embodiment A second embodiment of the present invention will be described.

[0038] In this embodiment, the surrounding detection devices 5a, 5b, and 5c are capable of distinguishing between multiple detection targets, and the controller 110 (control device) switches the detection target depending on the work state switched by the work state switching device 101.

[0039] The perimeter detection devices 5a, 5b, and 5c determine the type of detection target based on at least one feature associated with each of various types of objects and people that can be selected as detection targets. This makes it possible to determine whether the detected target is a person, such as a worker, or another obstacle, such as a structure. Note that, although the present embodiment illustrates a case in which the type of detection target is determined by the perimeter detection devices 5a, 5b, and 5c, it is also possible to configure the device to transmit information detected by the perimeter detection devices 5a, 5b, and 5c to the alarm control unit 112, and then determine the type of detection target based on the feature, etc., in the alarm control unit 112.

[0040] The detection range determination unit 111 switches the detection target depending on the work state switched by the work state switching device 101. In other words, depending on the work state, it switches which type of object (person) among the workers and other structures detected by the perimeter detection devices 5a, 5b, and 5c is to be the target of the detection / non-detection determination in the detection range. For example, when the work state switching device 101 is switched to a work-enabled state, workers and other structures are the detection targets, and if the objects detected by the perimeter detection devices 5a, 5b, and 5c are workers or other structures, they are the targets of the determination of whether they are present in the detection range (i.e., they are the detection targets). On the other hand, when the work state switching device 101 is switched to a work-disabled state, only workers are the detection targets, and even if other structures are detected by the perimeter detection devices 5a, 5b, and 5c, they are not the targets of the detection / non-detection determination in the detection range.

[0041] The other configurations are the same as those of the first embodiment.

[0042] The present embodiment configured as above can also achieve the same effects as the first embodiment.

[0043] Furthermore, when a structure or the like is detected and an alarm is issued, it is not easy to move the structure, so the alarm cannot be cancelled and the annoying situation continues. However, according to this embodiment, unnecessary alarms can be cancelled immediately, so unnecessary annoyance caused by alarms can be avoided.

[0044] Furthermore, since the system continues to detect the worker and output an alarm, the operator can recognize that the worker is within the range and can urge the worker to evacuate. In other words, by evacuating the worker, safety can be ensured and bothersome alarms can be avoided.

[0045] Third Embodiment A third embodiment of the present invention will be described with reference to FIG.

[0046] In this embodiment, the controller 110 (controller) switches the strength of the sound of the attention (warning) from the alarm device 102 in accordance with the work state switched by the work state switching device 101. Here, the strength of the attention refers to, for example, the loudness of the warning sound, the interval between intermittent warning sounds, the strength of the warning tone of the warning sound, etc.

[0047] For example, when the work state switching device 101 is switched to a workable state and an obstacle is detected within the detection range, the alarm control unit 112 causes the alarm device 102 to issue a strong warning (for example, an alarm at a loud volume), and when the work state switching device 101 is switched to a work-unavailable state and an obstacle is detected within the detection range, the alarm control unit 112 causes the alarm device 102 to issue a weaker warning (for example, an alarm at a low volume).

[0048] FIG. 5 is a flowchart showing the contents of the surrounding detection process.

[0049] In FIG. 5 , the controller 110 determines whether the hydraulic excavator 100 is in a workable state, i.e., whether the work state switching device 101 has been switched to a workable state (step S100), and if the determination result is YES, sets the detection range for the workable state, i.e., the first range 121, as the detection range (step S110).

[0050] Also, if the judgment result in step S100 is NO, that is, if the work state switching device 101 is switched to a work-unavailable state, the detection range for the work-unavailable state, that is, the second ranges 122a, 122b, and 122c, are set as the detection range (step S111).

[0051] When the process of setting the detection range (steps S110, S111) is completed, it is then determined whether or not there is a detection target within the set detection range (step S120), and if the determination result is NO, the process returns to step S100 without issuing a warning to the operator.

[0052] Furthermore, if the determination result in step S120 is YES, it is then determined whether or not work is possible (step S140), and if the determination result is YES, the alarm device 102 issues a strong sound to alert (warn) the operator of the cab 4 (step S150), and the process returns to step S100.

[0053] Also, if the judgment result in step S140 is NO, that is, if the work state switching device 101 is switched to a work-disabled state, the alarm device 102 issues a low-intensity sound to alert (warn) the operator of the cab 4 (step 151), and the process returns to step S100.

[0054] The other configurations are the same as those of the first embodiment.

[0055] The present embodiment configured as above can also achieve the same effects as the first embodiment.

[0056] Furthermore, in a workable state where there is a possibility of contact with an obstacle, the operator can be reliably notified of the presence of the obstacle.

[0057] Furthermore, in a non-workable state where there is no possibility of contact with an obstacle, a muted alarm can be used to notify the operator of the presence of an obstacle while reducing the annoyance felt by the operator.

[0058] <Others> The present invention is not limited to the above-described embodiments and includes various modifications within the scope of the gist thereof. For example, the present invention is not limited to those including all of the configurations described in the above-described embodiments and includes those in which some of the configurations are omitted. Furthermore, a portion of the configuration of one embodiment can be added to or replaced with a configuration of another embodiment. Furthermore, the components of the above-described control device, as well as their functions and execution processes, may be implemented in part or in whole by hardware (e.g., by designing logic that executes each function using an integrated circuit). Furthermore, the components of the above-described control device may be implemented as a program (software) that is read and executed by an arithmetic processing device (e.g., a CPU) to realize the functions of the control device. Information related to the program can be stored, for example, in semiconductor memory (e.g., flash memory, SSD), magnetic storage device (e.g., hard disk drive), and recording medium (e.g., magnetic disk, optical disk), etc.

[0059] DESCRIPTION OF SYMBOLS 1...Upper rotating body, 2...Front working machine, 2a...Boom, 2b...Arm, 2c...Bucket, 2d...Boom cylinder, 2e...Arm cylinder, 2f...Bucket cylinder, 3...Lower traveling body, 3a, 3b...Travel hydraulic motor, 4...Operator's cab, 5a, 5b, 5c...Surrounding detection device, 100...Hydraulic excavator, 101...Working state switching device, 102...Alarm device, 103...Monitor, 110...Controller (control device), 111...Detection range determination unit, 112...Alarm control unit, 121...First range, 122a, 122b, 122c...Second range, 123a, 123b, 123c...Narrow section

Claims

1. A construction machine comprising: a vehicle body; a driver's cab provided in the vehicle body and in which an operator sits; a surroundings detection device provided in the vehicle body for detecting obstacles around the vehicle body; an alarm device provided in the driver's cab; and a control device that issues a warning using the alarm device when the surroundings detection device detects an obstacle within a preset detection range, the construction machine further comprising a work state switching device for switching the construction machine between a workable state and a non-workable state, the control device setting a first range predetermined around the vehicle body as the detection range when the work state switching device switches to the workable state, and setting a second range around the vehicle body which is predetermined to be smaller than at least a portion of the first range as the detection range when the work state switching device switches to the non-workable state.

2. A construction machine according to claim 1, wherein the cab is positioned offset to one side in the vehicle width direction relative to the vehicle body, and the second range is defined such that the range on the cab side around the periphery of the vehicle body is smaller than the ranges in other directions.

3. A construction machine according to claim 1, wherein the warning device alerts the operator by at least one of a sound and a monitor display.

4. A construction machine as described in claim 1, characterized in that the control device switches between issuing and not issuing a warning via the alarm device depending on the work state of the construction machine switched by the work state switching device and the type of obstacle detected by the surroundings detection device.

5. A construction machine as described in claim 4, characterized in that, when the control device is switched to the workable state by the work state switching device, when the surroundings detection device detects an object or a person as the detection target in the first range, it issues a warning using the alarm device; when the control device is switched to the work unavailable state by the work state switching device, when the surroundings detection device detects an object as the detection target in the second range, it does not issue a warning using the alarm device; and when the surroundings detection device detects a person as the detection target in the second range, it issues a warning using the alarm device.

6. A construction machine as described in claim 1, characterized in that, when the control device is switched to the workable state by the work state switching device, if the surroundings detection device detects an obstacle in the first range, the control device issues a warning at a predetermined volume via the alarm device, and, when the control device is switched to the non-workable state by the work state switching device, if the surroundings detection device detects an obstacle in the second range, the control device issues a warning at a volume lower than the predetermined volume via the alarm device.

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