Approach detection device for heavy machinery

Abstract

To provide a highly reliable approach detection device for heavy machinery capable of forming a magnetic field that uniformly covers a work area surrounding the entire heavy machinery vehicle without omissions and capable of reliably detecting a worker entering the work area. [Solution] By covering the work area of ​​the forklift 11 with a magnetic field 21 formed by magnetic field generating means 15a, 15b attached to the vehicle body 12 of a forklift (an example of a heavy equipment vehicle) 11 and magnetic field generating means 17a, 17b attached to a horizontal arm 16 positioned protruding forward from the widthwise center of the front end of the vehicle body 12, when a worker carrying an RFID tag enters the work area, an alarm means is activated to issue an alarm to the driver and worker of the forklift 11.

Description

[Technical field]

[0001] The present invention relates to an approach detection device for heavy machinery, which is used to prevent workers from approaching heavy machinery vehicles such as forklifts that transport loads in a factory. [Background technology]

[0002] Conventionally, in a factory, various heavy machinery vehicles (heavy machinery) and many workers move around while performing various tasks, and there is a risk of contact between the heavy machinery vehicles and workers who enter the work area. Even if the driver of the heavy machinery vehicle and the worker pay attention, they may be in each other's blind spots or may miss each other due to looking away or carelessness, so it is difficult to completely prevent contact between the heavy machinery vehicles and workers by visual confirmation alone. Therefore, Patent Documents 1 and 2 disclose a trigger ID type detection system that uses a magnetic field generator (trigger signal transmitter) and an RFID tag (ID tag) to detect a worker approaching a heavy machinery (work machine) and issue an alarm.

[0003] The heavy equipment (work machines) that are the target of the detection systems in Patent Documents 1 and 2 all have a working unit, such as a movable arm member or a multi-jointed work machine, connected to the front of the vehicle body, and the longitudinal dimension (total length) is significantly longer than the width dimension, and the working area is also vertically long. However, the magnetic field generating device (trigger signal transmitter) is only attached to the main body of the vehicle (the driver's cab or the upper rotating body) and is not attached to the working unit, which poses a problem in ensuring the desired detection range around the working unit, especially the tip side of the working unit and the working area forward of the tip of the working unit. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2016-115038 A [Patent Document 2] JP 2019-60108 A DISCLOSURE OF THEINVENTION [Problem to be solved by the invention]

[0005] One possible solution to the above problem is to increase the output of a magnetic field generating device attached to the main body of the vehicle so that the working section is also covered by the magnetic field. However, the range of the magnetic field generated by the magnetic field generator spreads almost evenly in the front, back, left and right directions from the center of the magnetic field generator, and is elliptical in shape when viewed from above, so even if it were possible to cover the entire length of the heavy equipment, including the working part, with the magnetic field, the range in which the magnetic field is generated would unnecessarily spread in the width direction of the heavy equipment (beyond the working area).As a result, there is a risk that an excessive alarm will be issued by detecting workers in a safe area outside the working area to the side of the heavy equipment, resulting in a problem of lack of reliability. Furthermore, when work is carried out in an area where multiple work areas are adjacent to each other, if the magnetic field range extends into the adjacent work areas, a worker working in the adjacent work area may be mistakenly detected, resulting in reduced work efficiency. Therefore, when detecting workers entering each work area, in order to avoid missing detections or detecting workers in work areas that are not subject to detection, the magnetic field formed for each piece of heavy equipment must cover each target work area uniformly without any omissions. Therefore, in order to realize a highly reliable approach detection device for heavy machinery, it is extremely important to determine how to arrange multiple magnetic field generating devices relative to the target heavy machinery and how to set the range of the magnetic field emitted from each magnetic field generating device.

[0006] The present invention has been made in consideration of the above-mentioned circumstances, and its object is to provide a highly reliable approach detection device for heavy machinery that can form a magnetic field that uniformly covers not only the vehicle body but also the work area surrounding the entire heavy machinery vehicle, including the working section of the heavy machinery vehicle, without any omissions, and can reliably detect workers entering the work area. [Means for solving the problem]

[0007] The approach detection device for heavy machinery according to the present invention, which is in accordance with the above-mentioned object, is equipped with a magnetic field generating means, a control unit, and an alarm means, which are attached to a heavy machinery vehicle having a working section at the front of the vehicle body, and the control unit receives a radio wave signal transmitted from an RFID tag carried by a worker who has entered the working area of ​​the heavy machinery vehicle, and activates the alarm means to issue an alarm to the driver of the heavy machinery vehicle and the worker, thereby preventing the heavy machinery vehicle from approaching the worker, The work area of ​​the heavy vehicle is covered with a magnetic field generated by the magnetic field generating means attached to one or both of the vehicle body of the heavy vehicle and a horizontal arm arranged to protrude forward from the vehicle body.

[0008] In the heavy machinery approach detection device according to the present invention, it is preferable that the magnetic field generated by the magnetic field generating means and covering the work area has an elliptical shape surrounding the outer periphery of the heavy machinery vehicle in a plan view.

[0009] In the heavy machinery approach detection device of the present invention, when a plurality of the work areas are arranged side by side, it is preferable that the level of the magnetic field generated by the magnetic field generating means is adjusted so as not to cover adjacent work areas.

[0010] In the heavy equipment approach detection device of the present invention, it is preferable that the protruding length of the horizontal arm is the same as the protruding length of the working part of the heavy equipment vehicle, one of the magnetic field generating means is attached to the rear end of the vehicle body of the heavy equipment vehicle, and one of the magnetic field generating means is attached to the tip of the horizontal arm.

[0011] In the approach detection device for heavy machinery of the present invention, it is preferable that the working unit is held on the vehicle body so that it can be raised and lowered, and the horizontal arm is attached to the upper side of the working unit and held so that it can be raised and lowered together with the working unit when the working unit is raised and lowered. Effect of the Invention

[0012] The heavy equipment approach detection device of the present invention is equipped with a horizontal arm that protrudes forward from the vehicle body of the heavy equipment vehicle. Therefore, a magnetic field generating means can be attached to the horizontal arm in addition to the vehicle body of the heavy equipment vehicle, and a magnetic field is formed that, when viewed in a plane, overlaps with the work area that surrounds the entire heavy equipment vehicle including the vehicle body and working unit, so that a worker entering the work area can be reliably detected and an alarm can be sounded, thereby preventing the heavy equipment vehicle from approaching the worker.

[0013] In the heavy equipment approach detection device of the present invention, when the magnetic field generated by the magnetic field generating means and covering the work area has an elliptical shape surrounding the outer periphery of the heavy equipment vehicle when viewed in a plane, the work area can be covered without any omissions by the magnetic field without any constrictions, and workers entering the work area can be reliably detected.

[0014] In the heavy machinery approach detection device of the present invention, when work is performed in a location where multiple work areas are arranged side by side, if the level of the magnetic field generated by the magnetic field generating means is adjusted so as not to cover adjacent work areas, the device will not mistakenly detect a worker who has entered another adjacent work area, and will have excellent reliability.

[0015] In the heavy equipment approach detection device of the present invention, when one magnetic field generating means is attached to the rear end of the vehicle body of a heavy equipment vehicle and one magnetic field generating means is attached to the tip of a horizontal arm having a protruding length approximately the same as the protruding length of the working part of the heavy equipment vehicle, the magnetic field formed by the two magnetic field generating means is extended in the longitudinal direction of the heavy equipment vehicle without expanding in the width direction of the heavy equipment vehicle when viewed in a plane, and the working area behind the rear end of the vehicle body and the working area in front of the tip of the horizontal arm are reliably covered with a magnetic field, making it possible to detect workers who have entered the working area and effectively prevent workers from coming close to the heavy equipment vehicle.

[0016] In the heavy equipment approach detection device of the present invention, when the horizontal arm is attached to the upper side of a liftable working unit provided on a heavy equipment vehicle and held so that it can be raised and lowered together with the working unit, when the working unit is raised during work, the horizontal arm is also raised, preventing contact between the horizontal arm and the cargo lifted by the working unit, and providing excellent operability. [Brief description of the drawings]

[0017] [Figure 1] 1 is a side view of a forklift equipped with an approach detection device for heavy machinery according to a first embodiment of the present invention. [Diagram 2] 4 is a plan view showing a forklift equipped with the approach detection device for heavy machinery and a detection range of the approach detection device for heavy machinery. FIG. BEST MODE FOR CARRYING OUT THEINVENTION

[0018] (Embodiment 1) Next, with reference to the attached drawings, an embodiment of the present invention will be described for understanding the present invention. An approach detection device 10 for heavy machinery (hereinafter referred to as "approach detection device 10") according to a first embodiment of the present invention shown in Figures 1 and 2 is mounted on a forklift (an example of a heavy machinery vehicle) 11 used to transport loads in a factory or the like, and prevents the forklift 11 from coming into contact with workers. 1 and 2, a forklift 11 has forks (one example of a working part) 13 that are liftably attached to the front of a vehicle body 12. The approach detection device 10 is not limited to the forklift 11, but can also be applied to heavy machinery vehicles other than a forklift that have a working part other than the forks 13, such as a well-known shovel.

[0019] The approach detection device 10 has two magnetic field generating means 15a, 15b, one at the front and one at the back, attached to the vehicle body 12. The approach detection device 10 also has a horizontal arm 16 that protrudes forward from the center in the width direction of the front end of the vehicle body 12 and is positioned above the fork 13. Two magnetic field generating means 17a, 17b are attached to the horizontal arm 16.

[0020] In this embodiment, the horizontal arm 16 is attached to the upper side of the mast 18 of the forklift 11 and can be raised and lowered together with the mast 18 when the forks 13 are raised and lowered, but the horizontal arm 16 only needs to be able to be raised and lowered as necessary when the forks 13 are raised and lowered, and the attachment position and the method of raising and lowering (lifting mechanism) are not limited to this embodiment and can be selected as appropriate. Note that if the height of the load is limited and it is clear that the load and the horizontal arm 16 will not come into contact with each other even when the load is lifted by the forks 13, the horizontal arm 16 does not need to be able to be raised and lowered relative to the vehicle body 12.

[0021] In this embodiment, the magnetic field generating means 15a and 15b are arranged on the upper surface of the front side of the driver's cab 19 of the vehicle body 12 and on the upper surface of the rear end of the vehicle body 12, and the magnetic field generating means 17a and 17b are arranged on the upper surface of the tip end of the horizontal arm 16 and on the upper surface of the longitudinal center of the horizontal arm 16. Here, the protruding length of the horizontal arm 16 is approximately the same as the protruding length of the fork 13, and the magnetic field generating means 15a, 15b, 17a, and 17b are arranged at approximately equal intervals with respect to the entire length of the forklift 11 (vehicle body 12 + fork 13). The protruding length of the horizontal arm 16 is appropriately selected depending on the range of the work area in front of the fork 13 and the range of the magnetic field formed by the magnetic field generating means attached to the horizontal arm 16, and may be shorter than the protruding length of the fork 13. The arrangement interval of the magnetic field generating means is also appropriately selected.

[0022] When the magnetic field generating means 15a, 15b, 17a, and 17b each transmit (output) a trigger signal (also called a trigger magnetic field or a magnetic field signal), a magnetic field is formed in all directions (spherical) with each of the magnetic field generating means 15a, 15b, 17a, and 17b as the center. When viewed from above, as shown by the dashed lines in FIG. 2, an elliptical magnetic field 20 is formed with each of the magnetic field generating means 15a, 15b, 17a, and 17b as the center. Then, the four elliptical magnetic fields 20 in a planar view are connected while overlapping each other, so that as a whole, an oval magnetic field 21 in a planar view that surrounds the outer periphery of the forklift 11 is formed as shown by the solid lines in FIG. This allows the working area of ​​the forklift 11 to be covered with the magnetic field 21. In this way, a magnetic field 21 of approximately constant width without any constrictions (irregularities) is formed along the outer periphery (outermost shape) of the forklift 11, making it possible to detect any worker entering the work area (approaching the forklift 11) without fail.

[0023] In particular, in this embodiment, one magnetic field generating means 15b is attached to the rear end of the vehicle body 12 and one magnetic field generating means 17a is attached to the tip of the horizontal arm 16, so that the work area behind the rear end of the vehicle body 12 and the work area in front of the tip of the fork 13 (horizontal arm 16) can be reliably covered with the magnetic field 21, thereby improving the effect of preventing the forklift 11 from coming close to the worker.

[0024] The magnetic field generating means 15a, 15b, 17a, and 17b can adjust the output of the trigger signal. Therefore, when working in a place where a plurality of partitioned work areas are arranged side by side, the level of the magnetic field 21 formed by the magnetic field generating means 15a, 15b, 17a, and 17b is adjusted so as not to cover the adjacent work areas. As a result, the adjacent work areas are excluded from the detection range, and a worker who has entered the adjacent work area is not mistakenly detected, and only the worker who has entered each work area can be reliably detected.

[0025] In this embodiment, the working area is approximately a = 3 m forward from the tip (front end) of the fork 13, and b = 2 m on each side of the fork 13, but this range can be appropriately selected depending on the working conditions and the conditions of the heavy equipment vehicle, such as the type of cargo to be transported (shape, size, and weight), the dimensions of the forklift 11 (total length and total width), and the spacing between the forklifts 11 (distance from adjacent forklifts 11).

[0026] In addition, in this embodiment, two magnetic field generating means are attached to each of the vehicle body 12 and the horizontal arm 16, but the approach detection device 10 only needs to be equipped with a magnetic field generating means on one or both of the vehicle body 12 and the horizontal arm 16, and the number and arrangement of the magnetic field generating means can be appropriately selected depending on the overall length of the vehicle body 12, the protruding length of the forks 13, the range (size) of the work area, etc.

[0027] The approach detection device 10 includes an RFID tag (not shown) carried by a worker working near the forklift 11, an alarm means (not shown) attached to one or both of the forklift 11 and the horizontal arm 16, and a control unit (not shown) attached to the vehicle body 12. The RFID tag is attached to a helmet, work clothes, or the like worn by a worker. When a worker carrying an RFID tag enters a work area covered by magnetic field 21, a radio signal is emitted from the RFID tag. When the control unit receives the radio signal emitted from the RFID tag, the control unit transmits an alarm output signal to the alarm means. As a result, the alarm means issues an alarm to the driver 22 of the forklift 11 and the worker. When the alarm is issued, the driver 22 immediately stops the forklift 11 and the worker stands still, thereby preventing the forklift 11 from coming close to the worker.

[0028] Here, the control unit and the magnetic field generating means 15a, 15b, 17a, and 17b are connected by cables (not shown), and power is supplied from the control unit to the magnetic field generating means 15a, 15b, 17a, and 17b. The control unit also has an antenna (monopole antenna, not shown) for receiving radio signals transmitted from the RFID tag. In this embodiment, the control unit and the antenna are installed inside the cab 19 of the vehicle body 12, but the installation positions of the control unit and the antenna are not limited to this embodiment, and a desired position of the vehicle body 12, such as the upper surface of the cab 19, may be appropriately selected. In addition, the antenna may be fixed and integrated with the control unit, or may be connected to the control unit by an RF cable and installed at a position away from the control unit.

[0029] The warning means may be any means capable of notifying the driver 22 and the worker of the forklift 11 of danger by either or both of light and sound. Specific warning means include, for example, a light that turns on or flashes yellow or red, a buzzer or siren that emits various warning sounds, and a speaker that notifies of danger by voice. These warning means may be used alone or in combination. The number and arrangement of the warning means may be selected as appropriate.

[0030] The above describes the embodiment of the present invention, but the present invention is not limited to the configuration described in the above embodiment, and also includes other embodiments and modified examples that are possible within the scope of the matters described in the claims of the utility model registration. The method of fixing the magnetic field generating means to the vehicle body and the horizontal arm may be appropriately selected, but it is preferable that the magnetic field generating means be detachably attached so that it can be removed as necessary during inspection or when a malfunction occurs. For example, the magnetic field generating means may be fixed by magnetization or by a cable tie or the like. [Explanation of symbols]

[0031] 10: approach detection device, 11: forklift (heavy machinery vehicle), 12: vehicle body, 13: fork (working part), 15a, 15b: magnetic field generating means, 16: horizontal arm, 17a, 17b: magnetic field generating means, 18: mast, 19: driver's cab, 20, 21: magnetic field, 22: driver

Claims

1. A heavy machinery approach detection device comprising a magnetic field generating means, a control unit, and an alarm means, which are attached to a heavy machinery vehicle having a working unit at the front of a vehicle body, and which prevents the heavy machinery vehicle from approaching the worker by having the control unit receive a radio wave signal transmitted from an RFID tag carried by a worker who has entered a working area of ​​the heavy machinery vehicle and activates the alarm means to issue an alarm to the heavy machinery vehicle driver and the worker, An approach detection device for heavy machinery, characterized in that the work area of ​​the heavy machinery vehicle is covered with a magnetic field generated by the magnetic field generating means attached to one or both of the vehicle body of the heavy machinery vehicle and a horizontal arm arranged to protrude forward from the vehicle body.

2. 2. The heavy machinery approach detection device according to claim 1, wherein the magnetic field generated by the magnetic field generating means and covering the work area has an elliptical shape surrounding the outer periphery of the heavy machinery vehicle in a plan view.

3. 2. The approach detection device for heavy machinery according to claim 1, wherein when a plurality of the work areas are arranged side by side, the level of the magnetic field generated by the magnetic field generating means is adjusted so as not to cover adjacent work areas.

4. The protruding length of the horizontal arm is the same as the protruding length of the working part of the heavy equipment vehicle, 2. The approach detection device for heavy machinery according to claim 1, wherein one of said magnetic field generating means is attached to the rear end of said vehicle body of said heavy machinery vehicle, and one of said magnetic field generating means is attached to the tip end of said horizontal arm.

5. The working unit is supported on the vehicle body so as to be liftable and lowerable, 5. The approach detection device for heavy machinery according to claim 4, wherein the horizontal arm is attached to an upper side of the working unit and is held so as to be able to rise and fall together with the working unit when the working unit is raised and lowered.

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