Crane approach warning system

Abstract

The present invention provides a crane proximity warning system that can accurately determine whether a worker is positioned below the crane hook or the suspended load, regardless of the crane's installation location or the size of the suspended load. [Solution] The system comprises a master unit 2 installed in or near the operator's seat 11 of the crane 1 or near the crane 1, a hook-side sub-unit 3 attached to the hook portion 12 of the crane 1 or a suspended load 13 suspended from the hook portion 12 of the crane 1, and a worker-side sub-unit 5 attached to the worker 4. The three-dimensional positions of the master unit 2, the hook-side sub-unit 3, and the worker-side sub-unit 5 are determined by UWB communication between them, and an alarm is issued from at least one of the master unit 2 and the worker-side sub-unit 5 when the worker-side sub-unit 5 is located within a predetermined area below the hook-side sub-unit 3.

Description

Technical Field

[0001] The present invention relates to a crane approach warning system, and more particularly to an approach warning system between the hook or suspended load of a crane and an operator.

Background Art

[0002] As such a system, Patent Document 1 discloses the following system. "A system for generating a warning when the suspended load of a crane and an operator approach within a predetermined distance range in a plane, a crane current position information acquisition means attached to the tip of the boom of the crane or the hook portion, and acquiring the current position information of the tip of the boom or the hook portion; an operator current position information acquisition means for acquiring the current position information of an operator passing through the area where the crane is installed; comparing the current position information of the tip of the boom or the hook portion with the current position information of the operator, and determining whether the tip of the boom or the hook portion and the operator are approaching within a predetermined distance range in a plane centered on the tip of the boom or the hook portion; an alarm generation means for generating an alarm when the tip of the boom or the hook portion and the operator approach within a predetermined distance range in a plane centered on the tip of the boom or the hook portion; A crane suspended load and operator approach warning system, characterized by comprising the above."

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The problem that this invention aims to solve is to provide a crane proximity warning system that can accurately determine whether or not a worker is positioned below the crane hook or the suspended load, regardless of the crane's installation location or the size of the suspended load. [Means for solving the problem]

[0006] To solve the above problems, the inventors decided to incorporate a UWB communication system into the crane proximity warning system. That is, according to one aspect of the present invention, the following crane proximity warning system is provided.

[0007] The system comprises a master unit installed in or near the crane's operator's cab or the crane itself, a slave unit attached to the crane's hook or the load suspended from the crane's hook (hereinafter referred to as the "hook-side slave unit"), and a slave unit attached to the worker (hereinafter referred to as the "worker-side slave unit"). The master unit has at least three UWB communication units for transmitting and receiving UWB signals, and also includes a control unit with a calculation function. The hook-side slave unit is capable of sending and receiving UWB signals with each of the UWB communication units. The operator-side sub-unit is capable of sending and receiving UWB signals with each of the UWB communication units. The control unit calculates the three-dimensional position of the hook-side slave unit based on the distance information obtained by transmitting and receiving UWB signals between the hook-side slave unit and the respective UWB communication units, and also calculates the three-dimensional position of the worker-side slave unit based on the distance information obtained by transmitting and receiving UWB signals between the worker-side slave unit and the respective UWB communication units. Furthermore, the control unit determines whether the operator-side sub-unit is located within a predetermined area below the hook-side sub-unit based on the three-dimensional position of the hook-side sub-unit and the operator-side sub-unit, and when the operator-side sub-unit is located within the predetermined area, it issues an alarm from at least one of the master unit and the operator-side sub-unit, in a crane proximity alarm system. [Effects of the Invention]

[0008] According to the present invention, the three-dimensional positions of the hook-side and worker-side sub-units can be accurately determined by UWB communication between the master unit installed on the crane side and the hook-side and worker-side sub-units. This makes it possible to accurately determine whether or not a worker is positioned below the crane hook or the suspended load, regardless of the crane's installation location or the size of the suspended load. [Brief explanation of the drawing]

[0009] [Figure 1] A conceptual diagram illustrating the overall configuration of a crane proximity warning system, which is one embodiment of the present invention. [Figure 2] A block diagram showing the configuration of the master unit in the crane proximity warning system shown in Figure 1. [Figure 3] Figure 1 is a block diagram showing the configuration of the hook-side sub-unit and the operator-side sub-unit in the crane proximity warning system. [Modes for carrying out the invention]

[0010] Figure 1 conceptually shows the overall configuration of a crane proximity warning system, which is one embodiment of the present invention. The crane proximity warning system shown in Figure 1 comprises a master unit 2 installed in the operator's seat 11 of the crane 1, a hook-side slave unit 3 attached to the hook portion 12 of the crane 1, and a worker-side slave unit 5 attached to the worker 4.

[0011] As shown in Figure 2, the master unit 2 has three UWB communication units for transmitting and receiving UWB signals. These three UWB communication units each include a UWB antenna and have substantially the same configuration, but are labeled 21a, 21b, and 21c in Figure 2 to distinguish their installation locations. These UWB communication units 21a, 21b, and 21c are installed, for example, at a distance of about 50 cm from each other. In addition to the UWB communication units 21a, 21b, and 21c, the master unit 2 includes a control unit 22 with calculation functions, an alarm unit 23 that issues alarms, a power supply unit 24 that supplies power to each unit, and a user interface 25.

[0012] As shown in the upper part of Figure 3, the hook-side slave unit 3 includes a UWB communication unit 31, a control unit 32, and a power supply unit 34. The UWB communication unit 31 is capable of transmitting and receiving UWB signals with the three UWB communication units 21a, 21b, and 21c on the master unit 2. The control unit 32 controls the transmission and reception of the UWB signals. The power supply unit 34 supplies power to each unit.

[0013] As shown in the lower part of Figure 3, the worker-side slave unit 5 includes a UWB communication unit 51, a control unit 52, an alarm unit 53, and a power supply unit 54. The UWB communication unit 51, like the UWB communication unit 31 of the hook-side slave unit 3 described above, is capable of transmitting and receiving UWB signals with the three UWB communication units 21a, 21b, and 21c on the master unit 2. The control unit 52 controls the transmission and reception of the UWB signals. The alarm unit 53 issues an alarm. The power supply unit 54 supplies power to each unit. Thus, the worker-side slave unit 5 has the same configuration as the hook-side slave unit 3, except that it includes the alarm unit 53.

[0014] In the above configuration, the control unit 22 of the master unit 2 calculates the three-dimensional position of the hook-side slave unit 3 based on UWB communication with the hook-side slave unit 3, and also calculates the three-dimensional position of the worker-side slave unit 5 based on UWB communication with the worker-side slave unit 5. Specifically, the three-dimensional position of the hook-side slave unit 3 can be described as follows: Distance information between the hook-side slave unit 3 and the UWB communication unit 21a of the master unit 2 can be obtained by transmitting and receiving UWB signals between the hook-side slave unit 3 and the UWB communication unit 21a of the master unit 2. Similarly, distance information between the hook-side slave unit 3 and the UWB communication unit 21b of the master unit 2 can be obtained by transmitting and receiving UWB signals between the hook-side slave unit 3 and the UWB communication unit 21c of the master unit 2 can be obtained by transmitting and receiving UWB signals between the hook-side slave unit 3 and the UWB communication unit 21c of the master unit 2. The control unit 22 of the master unit 2 calculates the three-dimensional position of the hook-side slave unit based on the distance information obtained in this way. Similarly, the three-dimensional position of the worker-side slave unit 5 is also determined by the transmission and reception of UWB signals between the worker-side slave unit 5 and the UWB communication units 21a to 21c of the master unit 2. Distance information between the worker-side slave unit 5 and the UWB communication units 21a to 21c of the master unit 2 is obtained, and the control unit 22 of the master unit 2 calculates the three-dimensional position of the worker-side slave unit 5 based on the distance information obtained in this way. In other words, in this embodiment, the control unit 22 of the master unit 2 calculates the three-dimensional position of the hook-side slave unit 3 based on the distance information obtained by transmitting and receiving UWB signals between the hook-side slave unit 3 and the respective UWB communication units 21a to 21c of the master unit 2, and also calculates the three-dimensional position of the worker-side slave unit 5 based on the distance information obtained by transmitting and receiving UWB signals between the worker-side slave unit 5 and the respective UWB communication units 21a to 21c of the master unit 2.

[0015] Furthermore, the technique of obtaining distance information by transmitting and receiving UWB signals between a master unit and a slave unit is well known, and this distance information can be obtained on either the master unit or the slave unit side. In this embodiment, the distance information is obtained on the slave unit side as follows. That is, for the hook-side slave unit 3, the hook-side slave unit 3 transmits and receives UWB signals with the UWB communication units 21a to 21c of the master unit 2, thereby obtaining distance information between the UWB communication units 21a to 21c, and adding its own ID information to the distance information and transmitting it to the master unit 2. Also, for the worker-side slave unit 5, the worker-side slave unit 5 transmits and receives UWB signals with the UWB communication units 21a to 21c of the master unit 2, thereby obtaining distance information between the UWB communication units 21a to 21c, and adding its own ID information to the distance information and transmitting it to the master unit 2. Then, the control unit 21 of the master unit 2 calculates the three-dimensional position of the hook-side slave unit 3 based on the respective distance information transmitted from the hook-side slave unit 3, and calculates the three-dimensional position of the worker-side slave unit 5 based on the respective distance information transmitted from the worker-side slave unit 5.

[0016] Furthermore, the control unit 21 of the master unit 2 determines whether the worker-side slave unit 5 is located within a predetermined area below the hook-side slave unit 3 based on the three-dimensional position of the hook-side slave unit 3 and the three-dimensional position of the worker-side slave unit 5, and when the worker-side slave unit 5 is located within the predetermined area, an alarm is issued from at least one of the alarm units of the master unit 2 and the worker-side slave unit 5.

[0017] Here, the above-mentioned "predetermined area" can be fixedly set, but in this embodiment, the range of the predetermined area can be set or changed by the user interface 25 of the master unit 2. That is, in this embodiment, the range of the predetermined area can be set or changed according to the shape and size of the suspended load 13, etc. Thereby, the predetermined area can be appropriately set according to the shape and size of the suspended load 13, etc., and the alarm can be appropriately issued. In the present invention, the "predetermined area" is the area below the hook-side slave unit. That is, in the present invention, an alarm is issued when the operator-side slave unit is located within the predetermined area, which is the area below the hook-side slave unit. In other words, no alarm is issued when the operator-side slave unit is located above the hook-side slave unit. Therefore, even if the operator approaches the suspended load for operations such as hooking before lifting the suspended load, as long as the operator-side slave unit is located above the hook-side slave unit, no alarm is issued, and unnecessary alarm issuance can be suppressed.

[0018] On the other hand, when the operator approaches the suspended load for operations such as hooking before lifting the suspended load, depending on the positional relationship between the operator and the hook, the operator-side slave unit may be located below the hook-side slave unit. In this case, an unnecessary alarm is issued. In order to suppress the issuance of such unnecessary alarms, in the present embodiment, the control unit 21 of the master unit 2 does not issue an alarm even if the operator-side slave unit 5 is located within the above-mentioned predetermined area when the height position of the hook-side slave unit 3 is below a predetermined height. The above-mentioned "predetermined height" can be set to about 1 m, for example.

[0019] Further, an alarm stop means may be included so that the alarm can be manually stopped when an unnecessary alarm is issued. This alarm stop means can be incorporated into the user interface 25.

[0020] As described above, the embodiments of the present invention have been described with reference to the drawings, but the present invention is not limited to these embodiments. For example, although this embodiment assumes that the crane is installed outdoors, the present invention can be applied without any problems even when the crane is installed indoors. That is, in the present invention, the three-dimensional positions of the hook-side sub-unit and the worker-side sub-unit are determined by UWB communication between the master unit installed on the crane side and the hook-side sub-unit and the worker-side sub-unit, so that buildings do not become an obstacle as when using GPS. Also, even if the suspended load is large, the suspended load does not become an obstacle. Moreover, the accuracy of the distance information (positioning) obtained by UWB communication is far higher than that of GPS. Thus, according to the present invention, it is possible to accurately determine whether or not a worker is positioned below the crane hook or the suspended load, regardless of the crane's installation location or the size of the suspended load.

[0021] In this embodiment, the master unit 2 is installed in the driver's seat 11 of the crane 1, but it may also be installed near the driver's seat 11 or near the crane 1. Furthermore, if the crane is installed indoors, the master unit 2 may be installed indoors near the crane.

[0022] Furthermore, in this embodiment, one hook-side sub-unit 3 is attached to the hook portion 12 of the crane 1, but it may also be attached to the suspended load 13. Also, there may be multiple hook-side sub-units. For example, if the suspended load is elongated, hook-side sub-units can be attached to both ends. When there are multiple hook-side sub-units, "below the hook-side sub-unit" refers to the hook-side sub-unit at the highest position. Regardless of whether there is one or multiple hook-side sub-units, the "predetermined area below the hook-side sub-unit" can be set or changed via the user interface 25. [Explanation of Symbols]

[0023] 1 Crane 11. Driver's seat 12 Hook section 13 Hanging load 2 Master Unit 21a, 21b, 21c UWB Communications Department 22 Control Unit 23 Alarm section 24 Power supply section 25 User Interface 3. Hook-side sub-unit 31 UWB Communication Department 32 Control Unit 34 Power supply section 4 Workers 5 Worker side slave unit 51 UWB Communication Department 52 Control Unit 53 Alarm section 54 Power supply section

Claims

1. The system comprises a master unit installed in or near the crane's operator's cab or the crane itself, a slave unit attached to the crane's hook or the load suspended from the crane's hook (hereinafter referred to as the "hook-side slave unit"), and a slave unit attached to the worker (hereinafter referred to as the "worker-side slave unit"). The master unit has at least three UWB communication units for transmitting and receiving UWB signals, and also includes a control unit with a calculation function. The hook-side slave unit is capable of sending and receiving UWB signals with each of the UWB communication units. The operator-side sub-unit is capable of sending and receiving UWB signals with each of the UWB communication units. The control unit calculates the three-dimensional position of the hook-side slave unit based on the distance information obtained by transmitting and receiving UWB signals between the hook-side slave unit and the respective UWB communication units, and also calculates the three-dimensional position of the worker-side slave unit based on the distance information obtained by transmitting and receiving UWB signals between the worker-side slave unit and the respective UWB communication units. Furthermore, the control unit determines whether the operator-side sub-unit is located within a predetermined area below the hook-side sub-unit based on the three-dimensional position of the hook-side sub-unit and the operator-side sub-unit, and when the operator-side sub-unit is located within the predetermined area, it issues an alarm from at least one of the master unit and the operator-side sub-unit, in a crane proximity alarm system.

2. The crane proximity warning system according to claim 1, wherein the master unit includes a user interface, and the range of the predetermined area can be set or changed by the user interface.

3. The crane proximity warning system according to claim 1 or 2, wherein the control unit does not activate the alarm even if the operator-side sub-unit is located within the predetermined area, if the height position of the hook-side sub-unit is below a predetermined height.

4. The crane proximity warning system according to claim 1 or 2, wherein the master unit includes a means for manually stopping the alarm from being issued.

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