Fall arrest device monitoring system and hook holder
The system addresses battery management and high costs by using kinetic energy to power fall arrest device monitoring, allowing remote management of fall arrest equipment usage without dedicated sensors, thus improving monitoring efficiency and reducing costs.
Patent Information
- Application Number
- JP2022137690
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2022-08-31
- Publication Date
- 2026-02-26
- Estimated Expiration
- 2042-08-31
AI Technical Summary
Existing fall arrest device monitoring systems require battery management, have high implementation costs due to dedicated sensors, and cannot effectively monitor workers in blind spots or from a distance.
A monitoring system for fall arrest equipment that uses a hook holder with a power generation unit converting kinetic energy into power, transmitting hook attachment/detachment states wirelessly, and a relay unit relaying data to a management server via a network, allowing remote monitoring without batteries.
Eliminates the need for battery management, supports low-cost implementation, and enables remote monitoring of fall arrest device usage status, enhancing convenience and effectiveness.
Smart Images

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Abstract
Description
[Technical Field]
[0001] The present invention relates to a system for monitoring the use of fall protection equipment by workers at a high-altitude work site. [Background technology]
[0002] When working at heights, such as at construction sites, workers are required to wear fall arrest equipment. Fall arrest equipment consists of a body belt worn by the worker and a lanyard connected to the body belt at one end and equipped with a hook at the other end. Workers put on the fall arrest equipment before working at height, and at the height work site, attach the hook to a lifeline, scaffolding handrail, building, or other attachment equipment, and then begin working at height. Fall arrest equipment is also called a safety harness.
[0003] To prevent falls, it is essential that workers use fall arrest equipment correctly and reliably. Therefore, a system has been proposed for encouraging workers to wear fall arrest equipment and for managing its usage status (see Patent Document 1). In the system described in Patent Document 1, sensors such as a pressure sensor and an open / close sensor, as well as a transmission circuit that wirelessly transmits sensor signals, are attached to the hook, and a control box is attached to the body belt. The control box includes a sensor signal receiver, a speaker, an LED, and a control device. The control device of the control box performs various alarm control using the speaker and LED based on the sensor signals received from the hook, and transmits the usage status of the fall arrest equipment to a personal computer via wireless communication. The personal computer manages the usage status received from the control box and controls the alarm as necessary. A manager operates the personal computer to monitor the usage status of the fall arrest equipment by the workers.
[0004] Furthermore, Non-Patent Document 1 describes an LED lamp attached to a fall arrest device, which includes a hook hanger unit that holds the hook and an LED light-emitting unit that alerts workers. The hook hanger unit is equipped with a sensor that detects the hook's holding status, and the LED light-emitting unit controls the LED light emission based on the detection result of the sensor. With this configuration, a manager located away from the worker can monitor the worker's use of the fall arrest device by checking the LED light emission status. [Prior art documents] [Patent documents]
[0005] [Patent Document 1] Patent No. 5116815 [Non-patent literature]
[0006] [Non-Patent Document 1] "GENTI MITEL (Mitel) LED Safety Belt Lamp," [online], [searched July 11, 2022], Internet<URL: https: / / 33ryou.com / products1195> Summary of the Invention [Problem to be solved by the invention]
[0007] However, the system described in Patent Document 1 uses a dedicated hook equipped with sensors as a fall arrest device, which means that existing fall arrest devices cannot be used and the introduction cost is high.On the other hand, the system described in Non-Patent Document 1 has the problem that it cannot monitor workers if they are in a blind spot from the manager's perspective.
[0008] Furthermore, the devices described in Patent Document 1 and Non-Patent Document 1 each require a battery for the device attached to the fall arrest device. While non-rechargeable primary batteries or rechargeable secondary batteries (storage batteries) can be used as the battery, primary batteries need to be replaced periodically, and secondary batteries need to be charged periodically, which poses the problem of requiring a great deal of effort for proper operation.
[0009] The present invention was made in consideration of the above circumstances, and its purpose is to provide a monitoring system for fall arrest equipment that does not require the effort of battery management, can be managed by an administrator from anywhere, and has low implementation costs. [Means for solving the problem]
[0010] In order to achieve the above-mentioned object, the present invention provides a monitoring system for monitoring the usage status of fall arrest equipment worn by workers, comprising a hook holder worn by the worker and a relay unit installed at a high-altitude work site, wherein the hook holder comprises a hook holding portion for holding a hook attached to the end of the lanyard of the fall arrest equipment, a hook attachment / detachment state detection means for detecting the attachment / detachment state of the hook relative to the hook holding portion, a first transmission circuit for wirelessly transmitting hook attachment / detachment state information, which is information relating to the attachment / detachment state of the hook detected by the hook attachment / detachment state detection means, to the relay unit, and a first power generation portion for generating power using kinetic energy relating to the worker's movement and supplying power to the first transmission circuit, and wherein the relay unit comprises a first receiving circuit for receiving the hook attachment / detachment state information from the first transmission circuit, and relay means for relaying the hook attachment / detachment state information received by the first receiving circuit to a specified management server via a network. [Effects of the Invention]
[0011] According to the present invention, the first transmitting circuit of the hook holder operates on power supplied from the first power generating unit, which generates power using the kinetic energy of the worker, eliminating the need for battery management for the hook holder. Furthermore, according to the present invention, a manager can access a specified management server via a network to monitor hook attachment / detachment status information as the usage status of the fall arrest device, meaning that the manager can manage the usage status of the fall arrest device no matter where they are. Furthermore, according to the present invention, conventional fall arrest devices can be used as is, resulting in low implementation costs. [Brief explanation of the drawings]
[0012] [Figure 1] System configuration diagram of a fall arrest device monitoring system [Figure 2] Front and side views of the hook holder [Figure 3] Hook holder functional configuration diagram [Figure 4] Relay unit functional configuration diagram DETAILED DESCRIPTION OF THE INVENTION
[0013] A monitoring system for fall arrest equipment according to one embodiment of the present invention will be described with reference to the drawings. Figure 1 is a system configuration diagram of the monitoring system for fall arrest equipment, Figure 2 is a front view and a side view of the hook holder, Figure 3 is a functional configuration diagram of the hook holder, and Figure 4 is a functional configuration diagram of the relay unit.
[0014] The monitoring system for fall arrest equipment according to this embodiment monitors the usage status of fall arrest equipment 10 worn by workers. As shown in Fig. 1, this monitoring system comprises a hook holder 100 attached to a worker 1 wearing the fall arrest equipment 10, a relay unit 200 installed at a high-altitude work site 2, a management server 300, and an administrator terminal 400 used by the administrator. Multiple relay units 200 can be placed at one site 2.
[0015] In this embodiment, the hook holders 100 are attached to the fall arrest device 10. Here, the number of hook holders 100 attached to one fall arrest device 10 is equal to the number of hooks 12 included in the fall arrest device 10, in other words, the number of lanyards 11. In the example of Figure 1, the fall arrest device 10 is equipped with two lanyards 11, and therefore is equipped with two hook holders 100.
[0016] The fall arrest device 10 is a conventional full harness type fall arrest device. This fall arrest device 10 includes a body belt worn around the body of the worker 1 and one or two lanyards 11 connected at one end to the body belt and having hooks 12 at the other end. The body belt includes a pair of shoulder belts that cross each other on the back and are worn over both shoulders, thigh belts that connect to the shoulder belts and are worn around the thighs, and a chest belt that connects the pair of shoulder belts around the chest. The hook holders 100 are detachably attached to each of the pair of shoulder belts of the fall arrest device 10.
[0017] 2, the hook holder 100 includes a box-shaped housing 101 and a buckle 102 connected to the rear side of the housing 101. The hook holder 100 is attached to the shoulder belt of the fall arrest device 10 by inserting the shoulder belt through insertion portions 102a formed above and below the buckle 102.
[0018] The housing 101 is a box-shaped body in the shape of a substantially rectangular parallelepiped with an inclined upper and lower front surface. A rectangular window 101a is formed in the center of the front surface of the housing 101. A drive lever 111 constituting a hook attachment / detachment state detection means is exposed from this window 101a, protruding forward from the inside of the housing 101. The drive lever 111 is supported inside the housing 101, and the front end of the drive lever 111 is configured to be rotatable up and down. Here, the front end of the drive lever 111 is normally configured to be positioned approximately in the center of its vertical movable range due to spring bias. An LED 121, which will be described later, is provided on the top surface of the housing 101.
[0019] A hook hooking member 103 is attached to the buckle 102 as a member for holding the hook 12. The hook hooking member 103 is a rod-shaped member bent into a generally U-shape. The open end of the U-shape of the hook hooking member 103 is fixed to the lower part of the buckle 102. The hook hooking member 103 extends downward from the lower part of the buckle 102, and is further bent upward from the front, extending upward at a predetermined distance from the front surface of the housing 101. The bent end of the U-shape of the hook hooking member 103, i.e., the upper end, is bent slightly diagonally forward. Here, the lower part of the hook hooking member 103 serves as a holding portion for the hook 12. When the hook 12 is attached to or detached from the hook hooking member 103, the hook 12 passes through the gap between the hook hooking member 103 and the front surface of the housing 101. At this time, the hook 12 comes into contact with the drive lever 111, causing the drive lever 111 to rotate upward or downward. After the hook 12 has passed, the drive lever 111 returns to approximately the center of its movable range.
[0020] As shown in Figure 3, the hook holder 100 includes a hook attachment / detachment status information transmitting unit 110 for transmitting hook attachment / detachment status information to the management server 300, a hook attachment / detachment status information display unit 120 for displaying hook attachment / detachment status information, and a beacon transmitting unit 130 for transmitting a wireless beacon signal.
[0021] The hook attachment / detachment status information transmitting unit 110 includes the aforementioned drive lever 111, switch 112, a link mechanism 113 that links the operation of the drive lever 111 with the operation of the movable segment 112a of the switch 112, a wireless transmitting circuit 114, a power generating circuit 115, and a link mechanism 116 that links the operation of the movable segment 112a of the switch 112 with the movable portion 115a of the power generating circuit 115.
[0022] The switch 112 is a single-pole, double-throw switch, and the first terminal 112b, second terminal 112c, and common terminal 112d are connected to the wireless transmission circuit 114. The switch 112 is also a rocker switch that is maintained in either a first open / closed state in which the movable segment 112a is shorted to the first terminal 112b, or a second open / closed state in which the movable segment 112a is shorted to the second terminal 112c, by spring bias or the like. In other words, the switch 112 is always in either the first open / closed state or the second open / closed state except during a transition period when the open / closed state is switched.
[0023] When the drive lever 111 is moved downward, the link mechanism 113 drives the movable segment 112a so that the switch 112 transitions from the first open / close state to the second open / close state. Therefore, the transition of the switch 112 to the second open / close state means that the hooking operation of engaging the hook 12 with the hook engaging member 103 has been performed. As described above, after the drive lever 111 is moved downward, it returns to the center of its movable range due to spring bias or the like, but it should be noted that the state transition of the switch 112 does not occur at this time. Therefore, when the switch 112 is in the second open / close state, the hook 12 is engaged with the hook engaging member 103, in other words, the hook 12 is not in use.
[0024] Similarly, when the drive lever 111 is operated upward, the link mechanism 113 drives the movable segment 112a so that the switch 112 transitions from the second open / close state to the first open / close state. Therefore, the transition of the switch 112 to the first open / close state means that a disengagement operation has been performed to disengage the hook 12 from the hook engaging member 103. As described above, the drive lever 111 returns to the center of its movable range due to spring bias or the like after being operated upward, but it should be noted that the switch 112 does not transition to a different state at this time. Therefore, when the switch 112 is in the first open / close state, the hook 12 is not engaged with the hook engaging member 103, in other words, it can be assumed that the hook 12 is being used.
[0025] With this configuration, the drive lever 111 , the switch 112 and the link mechanism 113 function as a hook attachment / detachment state detection means for detecting the attachment / detachment state of the hook 12 relative to the hook retaining member 103 .
[0026] The power generating circuit 115 includes a movable part 115a that reciprocates in response to the movement of the movable segment 112a of the switch 112 via a link mechanism 116, a permanent magnet 115b attached to the movable part 115a, an electromagnetic induction coil 115c disposed near the permanent magnet 115b, and a power supply circuit 115d for supplying power output from the electromagnetic induction coil 115c to the wireless transmission circuit 114. The power supply circuit 115d includes well-known circuits such as a rectifier circuit and a capacitor for temporary storage of electricity. With this configuration, the power generating circuit 115 generates power when the switch 112 is opened or closed, i.e., when the open / closed state of the switch 112 transitions, and supplies the power to the wireless transmission circuit 114. Here, the state transition of the switch 112 occurs when the drive lever 111 moves upward or downward, as described above. The drive lever 111 is driven during a hooking or unhooking operation. Therefore, the drive lever 111, the link mechanism 113, the link mechanism 116, and the power generation circuit 115 function as a power generation unit that converts the kinetic energy associated with the worker's movements, more specifically, the kinetic energy associated with the hooking or unhooking movements, into electricity.
[0027] When the open / close state of the switch 112 (the first open / close state or the second open / close state) transitions, the wireless transmitting circuit 114 wirelessly transmits the post-transition open / close state to the relay unit 200 as hook connection / detachment state information, which is information related to the hook connection / detachment state. Here, the data transmitted from the wireless transmitting circuit 114 includes at least a timestamp and its own identification information in addition to the hook connection / detachment state information. The timestamp may be time information measured by a timer included in the wireless transmitting circuit 114. The identification information may be its own address used in the data transmission protocol, or unique identification information set separately from the address. In this embodiment, the wireless transmitting circuit 114 is implemented to comply with the EnOcean (registered trademark) international standard communication specification (ISO / IEC 14543-3-10:2012).
[0028] The hook attachment / detachment state information display unit 120 includes an LED 121, an LED drive control circuit 122 that controls the drive of the LED 121 depending on the open / close state of the switch 112, and a vibration power generation unit 123 that supplies power to the LED drive control circuit 122.
[0029] In this embodiment, the LED drive control circuit 122 controls the LED 121 to emit light only when the switch 112 is in the second open / close state, i.e., when the hook 12 is hung on the hook hanging member 103. In yet another embodiment, the LED drive control circuit 122 controls the LED 121 to emit light only when the switch 112 is in the first open / close state, i.e., when the hook 12 is not hung on the hook hanging member 103.
[0030] The vibration power generation unit 123 converts kinetic energy associated with the worker's movements, more specifically, kinetic energy associated with vibrations caused by the worker's movements, into electric power. The vibration power generation unit 123 may include a storage battery and a charging circuit to constantly supply power to the LED drive control circuit 122. Note that the hook attachment / detachment state information display unit 120 may include an environmental power generation unit such as a solar power generation unit instead of or in addition to the vibration power generation unit 123.
[0031] The beacon transmitting unit 130 includes a beacon transmitting circuit 131 that wirelessly transmits a beacon to the surrounding area, and a vibration power generating unit 132 that supplies power to the beacon transmitting circuit 131.
[0032] The beacon transmission circuit 131 periodically wirelessly broadcasts its own identification information (beacon ID) to the surrounding area as a beacon signal. Here, the identification information used in the beacon may be the same as or different from the identification information transmitted together with the hook connection / disconnection status information. In this embodiment, BLE (Bluetooth (registered trademark) Low Energy) beacons are used as the standard for beacon transmission.
[0033] The vibration power generation unit 132 converts kinetic energy associated with the worker's movements, more specifically, kinetic energy associated with vibrations caused by the worker's movements, into electric power. The vibration power generation unit 132 may include a storage battery and a charging circuit to constantly supply power to the beacon transmission circuit 131. Note that the beacon transmission unit 130 may include an energy harvesting unit such as a solar power generator instead of or in addition to the vibration power generation unit 132.
[0034] Next, the relay unit 200 will be described with reference to FIG. 4. In the present invention, the hook holder 100 is not provided with a battery, but is operated by power converted from kinetic energy related to the worker's movement. Therefore, due to limitations on the amount of power generation, it is not possible to employ a communication circuit that consumes a lot of power, such as one that directly accesses a mobile communication network such as an LTE (Long Term Evolution) network. Therefore, in the present invention, the hook holder 100 employs a communication circuit that consumes a small amount of power, and is configured to relay data communication to the management server 300 via the relay unit 200. Note that the relay unit 200 accommodates multiple hook holders 100.
[0035] 4, the relay unit 200 includes a relay section 210 and an alarm section 220. The relay section 210 includes a wireless receiving circuit 211, a relay processing section 212, a network transmitting / receiving section 213, and a display section 214. The alarm section 220 includes a beacon receiving circuit 221, an alarm control section 222, and a speaker 223.
[0036] The wireless receiving circuit 211 corresponds to the wireless transmitting circuit 114 of the hook holder 100, and receives hook attachment / detachment state information, time stamp, and identification information transmitted by the wireless transmitting circuit 114.
[0037] The relay processing unit 212 relays the data (hook attachment / detachment state information, timestamp, identification information) received by the wireless receiving circuit 211 to the management server 300 using the network transmitting / receiving unit 213. The relay processing unit 212 also controls the display of the display unit 214 based on the data (hook attachment / detachment state information, timestamp, identification information) received by the wireless receiving circuit 211. Specifically, the relay processing unit 212 controls the display unit 214 to display the hook attachment / detachment state information together with the identification information.
[0038] The network transmission / reception unit 213 has a function of connecting to a network and a communication interface with the management server 300 via the network. The network transmission / reception unit 213 has one or more communication interfaces corresponding to the network to be connected. In this embodiment, the network transmission / reception unit 213 has an LTE (Long Term Evolution) communication module. Note that the communication path between the network transmission / reception unit 213 and the management server 300 is not important.
[0039] The display unit 214 is a known display means made up of, for example, an LED element or a liquid crystal panel.
[0040] The beacon receiving circuit 221 corresponds to the beacon transmitting circuit 131 of the hook holder 100 and receives the beacon signal transmitted by the beacon transmitting circuit 131 .
[0041] The alarm control unit 222 detects that a worker has entered the nearby area by receiving a beacon signal via the beacon receiving circuit 221. When the alarm control unit 222 detects that a worker has entered the nearby area, it controls the speaker 223 to issue a predetermined alarm. Here, the worker can be identified by referring to identification information (beacon ID) included in the beacon signal.
[0042] In this embodiment, the relay unit 200 has a built-in primary battery or secondary battery and operates on the power of this battery. In another embodiment, the relay unit 200 operates on power supplied from an external power supply. Note that the relay unit 200 is managed by an administrator, including battery management.
[0043] The management server 300 is a well-known computer arranged on a network. In this embodiment, the management server 300 is arranged on the Internet. That is, the management server 300 is implemented as a so-called cloud server. In another embodiment, the management server 300 is arranged in a mobile communication network to which the relay unit 200 is connected. That is, the management server 300 is implemented as a so-called edge server.
[0044] The management server 300 stores and holds data (hook attachment / detachment status information, timestamp, and identification information) received from the hook holder 100 via the relay unit 200. In addition to the data, the management server 300 can also store and hold the identification information of the relay unit 200 that relayed the data. The management server 300 also has a user interface unit that provides various data viewing and management functions to the administrator terminal 400 used by the administrator. Therefore, the administrator can refer to the hook attachment / detachment status information anywhere as long as the administrator terminal 400 has an environment in which it can access the management server 300. The communication path between the management server 300 and the administrator terminal 400 is not important.
[0045] According to the monitoring system for fall arrest equipment of this embodiment, the hook holder 100 does not require a battery and operates on power converted from the kinetic energy of the worker. Specifically, the process of transmitting hook attachment / detachment status information operates on power converted from kinetic energy related to the action of attaching and detaching the hook 12 to the hook engaging member 103. Furthermore, the light emission operation of the LED 121 and the beacon transmission process operate on power converted from vibration energy. This eliminates the need for battery management for the hook holder 100. Furthermore, because the hook holder 100 does not require a battery, the hook holder 100 can be implemented in a compact size.
[0046] Furthermore, according to the monitoring system for fall arrest devices of this embodiment, an administrator can monitor hook attachment / detachment status information as the usage status of the fall arrest device 10 by accessing the management server 300 via the network using the administrator terminal 400, meaning that the administrator can manage the usage status of the fall arrest device 10 wherever he or she is. The administrator can also monitor the usage status of the fall arrest device 10 by visually checking the LED 121 of the hook holder 100. This provides a high level of convenience.
[0047] Furthermore, according to the monitoring system for fall arrest equipment of this embodiment, conventional fall arrest equipment 10 can be used as is, so the introduction cost is low.
[0048] Although one embodiment of the present invention has been described in detail above, the present invention is not limited to the above embodiment, and various improvements and modifications may be made without departing from the spirit and scope of the present invention.
[0049] For example, in the above embodiment, the power generation circuit 115 that generates power by hooking and unhooking operations is used as the power source for the wireless transmission circuit 114, but further auxiliary power sources may be provided such as bio-power generation, such as vibration power generation, or environmental power generation, such as solar power generation, and a storage battery that stores the power generated by these.
[0050] In addition, in the above embodiment, beacon transmitter 130 is implemented as being built into housing 101 of hook holder 100, but it may also be implemented as a separate body from hook holder 100. In this case, the housing incorporating beacon transmitter 130 may be connected to housing 101 of hook holder 100 by a string, stay, or the like.
[0051] Furthermore, in the above embodiment, in order for the administrator to obtain any information regarding the usage status of the fall arrest equipment, the administrator needs to actively access the management server 300 using the administrator terminal 400, but the management server 300 may notify the administrator terminal 400 of the information. In this case, the notification from the management server 300 to the administrator terminal 400 may be the usage status of the fall arrest equipment itself, or it may be a notification that some kind of change, abnormality, etc. has occurred in the usage status. [Explanation of symbols]
[0052] 10...Fall arrest equipment 12...Hook 100...Relay unit 103...Hook latching member 110... Hook attachment / detachment state information transmission unit 111...Drive lever 112...Switch 113...Link mechanism 114...Radio transmitting circuit 115...Generator circuit 116...Link mechanism 120...Hook attachment / detachment status information display section 130...Beacon transmitter 200...Relay unit 210...Relay section 220...Alarm section
Claims
1. A monitoring system for monitoring the use of fall arrest equipment worn by workers, a hook holder attached to the worker; a relay unit to be installed at a high-altitude work site, The hook holder comprises a hook holding portion that holds a hook provided at the tip of a lanyard of a fall arrest device, a hook attachment / detachment state detection means that detects the attachment / detachment state of the hook with respect to the hook holding portion, a first transmission circuit that wirelessly transmits hook attachment / detachment state information, which is information relating to the attachment / detachment state of the hook detected by the hook attachment / detachment state detection means, to the relay unit, and a first power generation portion that generates power using kinetic energy relating to the movement of a worker and supplies the power to the first transmission circuit, The relay unit includes a first receiving circuit that receives hook connection / detachment state information from the first transmitting circuit, and relay means that relays the hook connection / detachment state information received by the first receiving circuit to a predetermined management server via a network. A monitoring system for fall arrest equipment.
2. The hook attaching / detaching state detecting means detects that a hooking operation for attaching a hook to the hook holding portion has been performed and that a hook detaching operation for detaching the hook from the hook holding portion has been performed, The first power generating unit converts kinetic energy related to the hooking operation and the unhooking operation into electric power.
2. A monitoring system for a fall arrest device according to claim 1.
3. the hook-attached / detached state detection means includes a switch that is set to a first open / closed state by a hook-on operation and to a second open / closed state by a hook-off operation, The first power generating unit includes a movable part linked to the movable piece of the switch, and converts kinetic energy associated with the movement of the movable part into electric power.
3. A monitoring system for fall arrest equipment according to claim 2.
4. The hook holder further includes a second transmission circuit that wirelessly transmits a beacon signal to the surrounding area, and a second power generation unit that generates power using the kinetic energy of the worker and supplies the power to the second transmission circuit, The relay unit includes a beacon detection circuit that detects a beacon from the second transmission circuit, and an alarm means that issues a predetermined alarm to an operator when the beacon detection circuit detects the beacon. A monitoring system for fall arrest equipment according to any one of claims 1 to 3.
5. A hook holder to be worn by a worker and used in a monitoring system for monitoring the use of fall arrest equipment worn by the worker, The fall arrest device includes a hook holding part that holds a hook attached to the tip of a lanyard of the fall arrest device, a hook attachment / detachment state detection means that detects the attachment / detachment state of the hook with respect to the hook holding part, a first transmission circuit that wirelessly transmits hook attachment / detachment state information, which is information related to the attachment / detachment state of the hook detected by the hook attachment / detachment state detection means, to a relay unit installed at a high-altitude work site, and a first power generation part that generates electricity using kinetic energy related to the movement of a worker and supplies power to the first transmission circuit. A hook holder characterized by:
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