JP7634877B2 - Safety belt hook locking detection device and worker safety confirmation system - Google Patents

Description

The present invention relates to a safety belt hook lock detection device that detects whether the hook of a safety belt worn by a worker is hooked onto a hook locking member, for example, when working at height using a high-altitude work vehicle, and a worker safety confirmation system that uses the safety belt hook lock detection device.

A vehicle for working at height is equipped with a work platform mounted on the vehicle body via a moving device (such as a boom device or a scissor device), and the moving device is operated to move the work platform to a desired position, and a worker on the work platform can perform work at height. When working at height using such a vehicle for working at height, the worker uses a safety harness to secure his or her body to the work platform. The safety harness comprises a belt that is wrapped around the worker's torso, a lifeline connected to the belt, and a hook attached to the end of the lifeline. By hooking the hook of the safety harness onto a hook locking member provided on the work platform before starting work, the worker will not fall to the ground even if he or she falls from the work platform.

With a safety belt configured in this way, if the worker forgets to hook the hook to the hook locking member, the safety belt cannot achieve its original purpose. Therefore, Patent Document 1 discloses a safety belt hook locking detection device that is provided with a lock detection means for detecting the hook locking state near the hook locking member provided on the work platform, and that restricts the movement of the work platform and outputs an alarm to the worker when the hook locking state is not detected by this lock detection means. Patent Documents 2 to 4 also disclose safety belt hook locking detection devices that include a lock detection means for detecting the hook locking state.

However, in these conventional safety belt hook engagement detection devices, not only the hook engagement member for attaching the safety belt hook, but also the engagement detection means for detecting the engagement state of the hook are fixed in specific positions, so the range in which the worker can move is limited, for example, to within a few tens of centimeters around the hook engagement member. In other words, while there are cases in which a worker wants to change his or her working position depending on the work situation, conventional safety belt hook engagement detection devices make it difficult for the worker to move around freely.

Publication No. 7-20159 JP 2009-96608 A JP 2011-079647 A Japanese Patent Application Publication No. 11-100198

The problem that this invention aims to solve is to provide a safety belt hook locking detection device that allows a worker to move freely, and a worker safety confirmation system that uses the safety belt hook locking detection device.

The gist of the present invention is as follows.
1.
A safety belt hook lock detection device that detects whether or not the hook of a safety belt worn on a worker's body is hooked on a rod-shaped hook locking member,
a device body that is detachably installed so as to surround the periphery of the hook engaging member;
the device body is movable along the laying direction of the hook engaging member and has a shape that sandwiches both sides of the hook when the hook is engaged with the hook engaging member;
The safety belt hook engagement detection device further includes a sensor capable of detecting the presence of the hook when the hook is engaged with the hook engagement member.
2.
The safety belt hook locking detection device described in claim 1, wherein the device main body includes a shutter, and when the device main body is attached to or detached from the hook locking member, the shutter is in a raised state, and when the hook is hung on the hook locking member, the shutter is in a lowered state.
3.
The safety belt hook locking detection device described in claim 1, wherein the device main body includes a hinge, and when the device main body is attached to or detached from the hook locking member, the hinge is in an open state, and when the hook is hung on the hook locking member, the hinge is in a closed state.
4.
4. The safety belt hook locking detection device according to any one of claims 1 to 3 , further comprising a control means for receiving a signal from the sensor, and a wireless transmission circuit electrically connected to the control means.
5.
A worker safety confirmation system comprising at least one safety belt hook locking detection device according to the above 4 and a receiving alarm device,
The receiving alarm device is capable of receiving information transmitted from the wireless transmitting circuit and outputting an alarm based on the received information, in the worker safety confirmation system.

According to the present invention, the device body of the safety belt hook locking detection device is detachable from the hook locking member, can move freely along the installation direction of the hook locking member, and has a shape that clamps both sides of the hook when the hook is hung on the hook locking member, so the worker can move freely to different positions.

1 is a conceptual diagram showing a state in which a worker safety confirmation system according to an embodiment of the present invention is used; 11A to 11C are diagrams showing examples of shapes of safety belt hooks. 1 is a conceptual diagram showing a state in which a safety belt hook engagement detection device according to an embodiment of the present invention is used. FIG. 13 is a conceptual diagram showing another example of a safety belt hook engagement detection device. FIG. 4 is a block diagram showing the configuration of a tag attached to the main body of the safety belt hook engagement detection device. FIG. 2 is a block diagram showing the configuration of a receiving alarm device.

Figure 1 conceptually shows the use of a worker safety confirmation system according to one embodiment of the present invention. The worker safety confirmation system 1 shown in the figure includes a safety belt hook locking detection device (hereinafter simply referred to as the "locking detection device") 3 installed on the work platform 21 of the aerial work vehicle 2, and a receiving alarm device 4 installed on the vehicle body 22 of the aerial work vehicle 2. The work platform 21 of the aerial work vehicle 2 is attached to the vehicle body 22 via a boom 23, and the boom 23 is operated to move the work platform 21 to a desired position, and a worker 5 on this work platform 21 performs high-altitude work. A safety belt 6 is also worn on the body of the worker 5. The safety belt 6 includes a belt 61 wrapped around the worker's torso, a lifeline 62 connected to the belt 61, and a hook 63 (see Figure 2) attached to the tip of the lifeline 62.

Figure 3 conceptually shows an example of an engagement detection device 3. This engagement detection device 3A detects whether or not the hook 63 of the safety belt 6 worn on the body of the worker 5 is hooked onto a rod-shaped hook engagement member 7. In this embodiment, the hook engagement member 7 is assumed to be a handrail provided on the workbench 21, but is not limited to this.

The locking detection device 3A includes a device body 31A that is detachably installed so as to surround the periphery of the hook locking member 7. This device body 31A can move freely along the installation direction of the hook locking member 7 (horizontal direction in this embodiment), and has a shape that sandwiches both sides of the hook 63 when the hook 63 is hung on the hook locking member 7. Specifically, the device body 31A includes a shutter 311A, and when the device body 31A is attached to or detached from the hook locking member 7, the shutter 311A is in a raised state, and when the hook 63 is hung on the hook locking member 7, the shutter 311A is in a lowered state. The position of the center of gravity of the device body 31A is set so that it is in the posture shown in FIG. 3 when it is installed so as to surround the periphery of the hook locking member 7.

Figure 4 conceptually shows another example of the locking detection device 3. This locking detection device 3B includes a device body 31B that is detachably installed so as to surround the periphery of the hook locking member 7. This device body 31B can move freely along the laying direction of the hook locking member 7 (horizontal direction in this embodiment), and has a shape that sandwiches both sides of the hook 63 when the hook 63 is hung on the hook locking member 7. Specifically, the device body 31B includes a hinge 311B, and when the device body 31B is attached to or detached from the hook locking member 7, the hinge 311B is in an open state, and when the hook 63 is hung on the hook locking member 7, the hinge 311B is in a closed state. Note that the position of the center of gravity of the device body 31A is set so that it assumes the posture shown in Figure 4 when it is installed so as to surround the periphery of the hook locking member 7.

The device bodies 31A and 31B (hereinafter collectively referred to as "device body 31") include a sensor capable of detecting the presence of the hook 63 when the hook 63 is hung on the hook locking member 7. In this embodiment, a magnet 64 is attached to the hook 63, and the presence of the hook 63 is detected by detecting the magnetism of this magnet 64. Specifically, a tag 32 is attached to the device body 31, and as shown in Figures 3 and 4, when the hook 63 is hung on the hook locking member 7, the magnet 64 attached to the hook 63 is positioned in the vicinity of the tag 32.

Figure 5 shows the configuration of the tag 32 as a block diagram. The tag 32 has a magnetic sensor as a means for detecting the magnetism of the magnet 64, an alarm means, a display means, an AC induction magnetic field receiving means, a radio transmission circuit and an antenna, a tag control means for controlling these, and a battery. When the magnetic sensor detects magnetism, the tag control means determines that the hook 63 is present, i.e., that the hook 63 is hooked on the hook locking member 7, and transmits radio waves containing information to that effect from the radio transmission circuit via the antenna. When the magnetic sensor does not detect magnetism, the tag control means determines that the hook 63 is not present, i.e., that the hook 63 is not hooked on the hook locking member 7, and transmits radio waves containing information to that effect from the radio transmission circuit via the antenna and can output an alarm. In this embodiment, the alarm is output as sound from the alarm means of the tag 32 and as light from the display means. Note that the radio waves transmitted from the tag 32 can be added with the unique identification information of the tag 32.

Figure 6 shows the configuration of the receiving alarm device 4 as a block diagram. The receiving alarm device 4 has an antenna and a receiving circuit to receive information (radio waves) transmitted from the tag 32. Then, when the device control means determines based on the received information that the tag 32 (magnetic sensor) has not detected the presence of the hook 63, i.e., that the hook 63 is not hooked on the hook engaging member 7, it causes the alarm means to output an alarm and transmits the alarm information to other devices such as a host computer.

The locking detection device 3 of this embodiment includes a means for defining the high-altitude work area. Specifically, it is equipped with an AC induction magnetic field transmission means 33 for defining the high-altitude work area by an AC induction magnetic field. In this embodiment, the AC induction magnetic field transmission means 33 is installed on the work platform 21 of the high-altitude work vehicle 2. That is, the AC induction magnetic field transmission means 33 transmits an AC induction magnetic field so as to cover the high-altitude work area. Then, when this AC induction magnetic field is received by the AC induction magnetic field receiving means of the tag 32, the tag control means determines that the device main body 31 is within the high-altitude work area. And in this embodiment, it is possible to output an alarm only when the device main body 31 is within the high-altitude work area. In other words, the tag control means can be configured to output an alarm only when the AC induction magnetic field receiving means receives an AC induction magnetic field (when the device main body 31 is within the high-altitude work area) even if the magnetic sensor does not detect magnetism (when it is determined that the hook 63 is not hung on the hook locking member 7). Furthermore, the tag control means can transmit radio waves from the wireless transmission circuit via the antenna, including information on whether the magnetic sensor is detecting magnetism (whether the hook 63 is hooked on the hook locking member 7) as well as information on whether the AC induction magnetic field receiving means is receiving the AC induction magnetic field (whether the device body 31 is within the high-altitude work area). Then, based on the received information, when the device control means determines that the hook 63 is not hooked on the hook locking member 7 and that the device body 31 is within the high-altitude work area, it can output an alarm from the alarm means and transmit the alarm information to another device such as a host computer.

As described above, according to this embodiment, it is possible to determine whether the hook 63 is hooked on the hook locking member 7 and to output an alarm based on the result of the determination. This makes it possible to confirm the safety of the worker 5 in the work platform 21 of the vehicle for high-altitude work 2. In this embodiment, the device body 31 of the locking detection device 3 is detachable from the hook locking member 7, and can move freely along the laying direction of the hook locking member 7. It also has a shape that clamps both sides of the hook 63 of the safety belt 6 when the hook 63 is hooked on the hook locking member 7, so that the worker 5 can freely move within the work platform 21 of the vehicle for high-altitude work 2. When multiple workers work within the work platform 21 of the vehicle for high-altitude work 2, the safety of each worker within the work platform 21 of the vehicle for high-altitude work 2 can be confirmed by preparing a device body 31 for each worker. In this case, each worker can also freely move within the work platform 21 of the vehicle for high-altitude work 2.

Modifications of this embodiment will be described below.
Variation (1)
In this embodiment, in order to detect the presence of the hook 63 when the hook 63 is hooked on the hook locking member 7, the magnet 64 is attached to the hook 63, and a means for detecting the magnetism of the magnet 64 (the magnetic sensor of the tag 32) is attached to the device body 31. However, as a means for detecting the presence of the hook 63, a means for passing a weak current through the device body and detecting the current can also be provided. Since the hook 63 is usually made of metal, the amount of current flowing through the device body 31 differs between when the hook 63 is present and when the hook 63 is not present. Therefore, when the amount of current detected by the means for detecting the current corresponds to the amount of current when the hook 63 is present, it can be determined that the hook 63 is present. Note that as a means for detecting the current in this modification (1), the magnetic sensor of the tag 32 shown in FIG. 5 can be replaced with an ammeter.

Modification (2)
In this embodiment, the high-altitude work area is defined by the AC induction magnetic field, but the high-altitude work area can also be defined by, for example, radio waves in addition to the AC induction magnetic field. In this case, the AC induction magnetic field transmitting means 33 shown in Fig. 1 should be replaced with radio wave transmitting means, and the AC induction magnetic field receiving means of the tag 32 shown in Fig. 5 should be replaced with radio wave receiving means.

Modification (3)
In this embodiment, the locking detection device 3 is installed on the work platform 21 of the vehicle for high-altitude work 2, but it can also be installed in other areas where high-altitude work is performed. In this case, the rod-shaped hook locking member can be a handrail installed in the high-altitude work area.

REFERENCE SIGNS LIST 1 Worker safety confirmation system 2 Aerial work vehicle 21 Work platform 22 Vehicle body 23 Boom 3, 3A, 3B Engagement detection device 31, 31A, 31B Device body 32 Tag 33 AC induction magnetic field transmitting means 4 Receiving alarm device 5 Worker 6 Safety belt 61 Belt 62 Lifeline 63 Hook 64 Magnet 7 Hook engagement member

Claims (5)

A safety belt hook lock detection device that detects whether or not the hook of a safety belt worn on a worker's body is hooked on a rod-shaped hook locking member,
a device body that is detachably installed so as to surround the periphery of the hook engaging member;
the device body is movable along the laying direction of the hook engaging member and has a shape that sandwiches both sides of the hook when the hook is engaged with the hook engaging member;
The safety belt hook engagement detection device further includes a sensor capable of detecting the presence of the hook when the hook is engaged with the hook engagement member. The safety belt hook locking detection device according to claim 1, wherein the device body includes a shutter, the shutter is in a raised state when the device body is attached to or detached from the hook locking member, and the shutter is in a lowered state when the hook is hung on the hook locking member. The safety belt hook locking detection device according to claim 1, wherein the device body includes a hinge, and the hinge is in an open state when the device body is attached to or detached from the hook locking member, and the hinge is in a closed state when the hook is hung on the hook locking member. 4. The safety belt hook locking detection device according to claim 1 , further comprising: a control means for receiving a signal from the sensor; and a wireless transmission circuit electrically connected to the control means. A worker safety confirmation system comprising at least one safety belt hook locking detection device according to claim 4 and a receiving alarm device,
The receiving alarm device is capable of receiving information transmitted from the wireless transmitting circuit and outputting an alarm based on the received information, in the worker safety confirmation system.

Images