JP7480994B2 - Locking state detection device - Google Patents

Description

The present invention relates to a locking state detection device used for the hooks of safety belts used when working at heights, and more specifically, to a device that can detect whether the hook is locked to a handrail, rope, etc.

Generally, when workers work at heights, they are required to wear a safety belt around their body. This safety belt is made up of a rope with hooks attached to both ends, with one hook attached to the worker's harness and the other hook attached to a handrail or rope at the workplace to prevent the worker from falling.

However, when such workers wear safety belts around their bodies, some workers may not hook the safety belt onto a handrail or similar object, which can lead to danger.

Therefore, a safety belt hook equipped with an engagement status detection function has been proposed to enable detection of whether or not the hook is engaged with a handrail or the like.

For example, in the patent document 1 listed below, a cover is attached so that the inner edge of the hook is exposed, and a lever is provided on the curved part on the inside of the cover, which rotates when it comes into contact with a handrail or the like, so that when the hook is engaged with the handrail or the like, the lever is rotated to detect the engaged state.

JP 2020-43964 A

However, the above structure has the following problems:

In other words, in the above patent document, the cover is attached by placing it over the upper edge of the hook, and the surface of the hook is pressed and fixed with a screw, and the lever on this cover is made to abut against the handrail, so that every time the hook is engaged, a load and impact are applied to the cover via the lever, making the cover prone to coming off. In particular, because safety belt hooks are engaged and removed repeatedly at work sites, they are subjected to large loads and impacts many times, which creates the problem that the cover can easily come off the hook.

In addition, if an optical sensor is attached to such a cover to detect the locked state, the optical axis holes of the light-emitting unit and the light-receiving unit must be long, otherwise external light will enter and cause false detection. However, simply providing the light-emitting unit and the light-receiving unit on the cover inevitably limits the length of the optical axis holes of the light-emitting unit and the light-receiving unit, causing problems such as external light such as sunlight entering and causing false detection.

The present invention was made with a focus on the above problems, and aims to provide a hook locking state detection device that can easily detect the locking state of the hook of an existing safety belt to a handrail or the like, prevents the cover from coming off the hook, and also prevents erroneous detection by the optical sensor.

That is, in order to solve the above-mentioned problems, the present invention provides an engagement state detection device attached to a hook which comprises a hook to be engaged with an engaged part such as a handrail or rope, and an opening which can be opened and closed to cover the opening for engaging the hook with the engaged part and which prevents the hook from coming off the engaged part, the device comprising: a cover body which is detachably attached to the hook and has a light-emitting part and a light-receiving part which detects whether the hook is engaged with the engaged part; and an inner cover which covers the curved inner edge of the hook and has optical axis holes for the light-emitting part and the light-receiving part of the cover body, and the inner cover is attached to the cover body.

This configuration not only prevents the cover body from coming off the hook even if a load or impact is applied, but also makes it possible to prevent false detections caused by external light entering the hole by lengthening the hole, since the inner cover has an optical axis hole.

In addition, in this invention, an inner cover is provided to cover the surface of the cover body.

This configuration ensures that handrails and other objects will not come into contact with the cover body when the hook is engaged, and the cover body will not come off the hook.

Furthermore, the inner cover is provided with an engaged portion that engages with an engaging portion provided on the surface of the cover body.

This configuration allows the cover body and the inner cover to be integrated at the engaging portion and the engaged portion, and the optical axis hole of the integrated cover body and the optical axis hole of the inner cover can be aligned.

In addition, a transparent protective member is provided on the optical axis hole of the cover body or the inner cover.

This configuration will prevent dust and other debris from getting into the optical axis hole, preventing false detections and other issues.

The protective member is also constructed from a member having front and back surfaces perpendicular to the optical axis.

This configuration makes it possible to prevent external light from entering the light receiving section by reflecting and refracting it, while allowing only the light from the light emitting section to pass through to the light receiving section.

According to the present invention, a hook-attached locking state detection device is provided that is attached to a hook that is attached to a locking portion such as a handrail or rope, and that has an opening that can be opened and closed to cover the opening for locking the hook to the locking portion and prevents the hook from coming off the locking portion. The device includes a cover body that is detachably attached to the hook and has a light-emitting portion and a light-receiving portion that detects whether the hook is locked to the locking portion, and an inner cover that covers the curved inner edge of the hook and has optical axis holes for the light-emitting portion and the light-receiving portion of the cover body. The inner cover is attached to the cover body, so that not only will the cover body not come off the hook even if a load or impact is applied, but also because the inner cover has an optical axis hole, the optical axis hole can be lengthened to prevent erroneous detection due to the intrusion of external light.

FIG. 1 is a diagram showing a hook to which a locking state detection device according to an embodiment of the present invention is attached. A diagram showing how the inner cover is attached in the same configuration. A diagram showing only the hook in the same configuration. FIG. 13 shows an optical axis hole and a protective member in the embodiment. Schematic cross-sectional view of A-A in FIG. FIG. 2 is an exploded perspective view of the locking state detection device according to the embodiment; A diagram showing the use of a system with a safety belt

One embodiment of the present invention will be described below with reference to the drawings.

In this embodiment, the hook 1 locking state detection device 2 is carried by a worker working at a height, as shown in Fig. 7, and is configured with a cover body 21 attached to the hook portion 11 constituting the hook 1, and a locking state detection unit 3 provided inside the cover body 21 and having a light emitting unit 31 (see Fig. 2) and a light receiving unit 32 that detect whether the hook 1 is locked to a locking portion 8 (see Fig. 7) such as a handrail. Characteristically, an inner cover 27 that covers the inner edge 12 of the hook portion 11 is attached to the cover body 21, and the inner cover 27 is integrated with the cover body 21 to prevent the cover body from coming off the hook portion 11, and an optical axis hole 34 from the light emitting unit 31 and the light receiving unit 32 is provided in the inner cover 27, so that the optical axis holes 33, 34 can be made longer overall. In the description of the embodiment, the curved inner opening edge of the hook 1 is referred to as the "inner edge 12," the curved outer edge of the hook 1 is referred to as the "outer edge 13," and the front side of the paper in Figure 1 is referred to as the "front surface" of the cover body.

The hook 1 to which the locking state detection device 2 is attached constitutes a lanyard for a safety belt, and is configured with a plate-shaped hook portion 11 configured in a hook shape, a slip-prevention device 14 that opens and closes the opening S of the hook portion 11, and a safety device 15 that prevents the slip-prevention device 14 from opening unexpectedly, as shown in FIG. 3 and other figures. When the hook 1 is to be locked to a locked portion 8 such as a handrail, the slip-prevention device 14 and the safety device 15 are held simultaneously and the slip-prevention device 14 is rotated to the inner opening area of the hook portion 11 to lock the hook portion 11 to the locked portion 8, and after the hook portion 11 is locked to the locked portion 8, the slip-prevention device 14 and the safety device 15 are restored to their original positions by the force of a spring (not shown), and the slip-prevention device 14 is fixed in contact with the safety device 15, preventing the slip-prevention device 14 from opening unexpectedly.

The locking state detection device 2 attached to this hook 1 is configured with a cover body 21, an inner cover 27, a locking state detection unit 3, etc., and is configured to be able to transmit a signal indicating that the hook 1 is locked to the locking portion 8 to an external center device 7 (Figure 7).

As shown in Figs. 1, 2, 5, etc., the cover body 21 is attached so as to sandwich the front and back of the hook portion 11 near the upper part, and is configured in a curved shape that follows the shape of the hook portion 11. The inner edge 26 of the cover body 21 (see Figs. 2 and 5) is provided so as to be located further inward from the inner edge 12 of the hook portion 11 when attached to the hook 1. In addition, when attaching the cover body 21, holes may be formed on the front and back of the hook portion 11 and fixed with bolts and nuts, but providing such holes reduces the strength of the hook portion 11. Therefore, here, instead of providing a hole that penetrates the hook portion 11, a slit 22 is provided on the inside of the cover body 21 as shown in Fig. 5, and the hook portion 11 is sandwiched into the slit 22 so that it can be fixed. The inner bottom 23 of the slit 22 is designed to abut against the outer edge 13 of the hook 11, and the surface of the hook 11 is covered with the inner bottom 23 abutted against the outer edge 13 of the hook 11. In this state, a screw 25 can be attached to a screw hole 24 provided on the surface of the cover body 21, and the pressing force of the screw 25 can be used to press against the surface of the hook 11 and fix it in place.

The locking state detection unit 3 provided on the cover body 21 is capable of detecting that the hook 1 is locked to the locked portion 8, and is configured here by providing an optical sensor having a light emitting unit 31 and a light receiving unit 32 on the left and right sides that straddle the center line in the vertical axis direction of the hook portion 11. The locked portion 8 is positioned so as to cross the optical axis, so that the "locking state" can be detected. Note that when such an optical sensor is provided, there is a possibility that external light such as sunlight may enter and cause erroneous detection. Therefore, as shown in FIG. 4, the light receiving unit 32 is provided deep inside the optical axis hole 33, which prevents direct entry of external light. In addition, a transparent protective member 35 is provided on the optical axis hole 33. This protective member 35 prevents the intrusion of dust from the outside, and is made of a material such as resin that has a front and back surface perpendicular to the optical axis, thereby reflecting external light that enters from an oblique direction and preventing erroneous detection.

Meanwhile, an inner cover 27 is attached to the inside of two protrusions 26a (see Figures 1 and 2) provided on the inner edge 26 of the cover body 21.

This inner cover 27 covers the inner edge 12 of the hook 11 and is attached integrally with the cover body 21. Note that this inner cover 27 may be provided only on the inside center so as not to cover the left and right optical axis holes 33 of the cover body 21, but if this is done, there is a possibility that the optical axis will be blocked if the inner cover 27 becomes thick. Therefore, in this embodiment, an optical axis hole 34 corresponding to the optical axis hole 33 of the cover body 21 is provided, and this makes it possible to lengthen the optical axis holes 33, 34 and prevent erroneous detection due to the intrusion of external light.

As shown in Figs. 1 and 2, the inner cover 27 is configured with an inner curved portion 28a that covers the inner edge portion 12 of the hook portion 11 and a front and back portion 28b that covers the front and back surfaces of the cover body 21, thereby covering the cover body 21 from the outside. When attaching the inner cover 27 to the cover body 21, a protrusion 29a that is an engaging portion is provided on the front and back surfaces of the cover body 21, and a recess 29b that is an engaged portion is provided on the inner cover 27, and by engaging and integrating them, the optical axis hole 33 of the cover body 21 and the optical axis hole 34 of the inner cover 27 are made to coincide. In addition, by covering the cover body 21 with the inner cover 27 in this way, the inner cover 27 can be made thicker, so that even if external light is irradiated from the left and right direction along the surface of the hook portion 11 (the left and right direction in Fig. 1), it is possible to make it difficult for external light to enter the optical axis holes 34 and 33. By engaging the hook 1, which has such a cover body 21 and inner cover 27, with the engaging portion 8, the optical axis is blocked, making it possible to detect the engaged state.

However, when the locked state is detected in this way, there is a possibility that the hook 1 may be moved while being locked to the ring 81 (see FIG. 7) of the harness, and even in such a case, the light may be blocked and the "locked state" may be detected. Therefore, a mounting detection unit 6 (see FIG. 6) is provided to detect that the hook 1 is attached to the ring 81 of the harness, and when the mounting detection unit 6 detects that the hook 1 is attached to the body, the detection function of the locked state detection unit 3 is stopped. Various methods are possible for such a mounting detection unit 6, but for example, a magnet 61 is attached to the body side, and a mounting detection unit 6 consisting of a magnet detection unit that detects the magnet 61 is provided on the hook 1 side. Then, when the magnet 61 approaches the detection area of the magnet detection unit, it is assumed that the hook 1 is attached to the body, and the function of the locked state detection unit 3 is stopped.

As shown in FIG. 6, a power supply unit 4 is attached to the cover body 21, and power is supplied from the power supply unit 4 to the locking state detection unit 3, the attachment detection unit 6, the transmission unit 5, etc. When the attachment detection unit 6 detects that the hook 1 has been removed from the body (i.e., when the locking state detection unit 3 is in an activated state) and the locking state detection unit 3 detects that the hook 1 is in an "locking state", a signal indicating that the hook 1 is in an "locking state" is wirelessly output to the center device 7 via the transmission unit 5. When transmitting the "locking state" to the center device 7, a signal may be output via Bluetooth (registered trademark) to a wireless terminal device 71 such as a smartphone carried by the worker, and the signal may be output from the wireless terminal device 71 to the center device 7.

The center device 7 records the locking state in chronological order, and determines whether the locking state pattern is included in a predetermined pattern to determine whether the hook 1 is properly locked to the locking portion 8 and alert the operator.

Next, we will explain the process for attaching the thus configured locking state detection device 2 to the hook 1, and the operation for performing work using this locking state detection device 2.

First, when attaching the locking state detection device 2 to the hook 1, the slit 22 of the cover body 21 is aligned with the outer edge 13 of the hook 11 and inserted from above. Then, the inner edge 26 of the cover body 21 is aligned with the curved portion of the inner edge 12 of the hook 11, and the screw 25 is attached to the screw hole 24 on the surface to fix the cover body 21 in place.

After the cover body 21 is fixed in this way, the inner cover 27 is then attached from the inner edge 12 of the hook portion 11. At this time, the inner cover 27 is attached so as to be positioned inside the two left and right protrusions 26a (see FIG. 2) provided on the inner edge 26 of the cover body 21, and the front and back parts 28b of the inner cover 27 cover the front and back surfaces of the cover body 21. Then, the protrusions 29a provided on the surface of the cover body 21 and the recesses 29b provided on the surface of the inner cover 27 are engaged and integrated with each other. At this time, the optical axis hole 33 of the cover body 21 and the optical axis hole 34 of the inner cover 27 are aligned, and the length of the optical axis hole can be increased. Also, even if the cover body 21 is in a state where it is easy to come off, the cover body 21 moves together with the inner cover 27, so that the optical axis holes 33 and 34 do not become misaligned.

After attaching the cover body 21 and the inner cover 27 in this manner, the power supply unit 4, the transmission unit 5, the attachment detection unit 6, the magnet 61, etc. are attached to the cover body 21.

Next, we will explain the operation of using the hook 1 with the locking state detection device 2 attached in this manner.

First, when a worker is on his way to the work site, he attaches the hook 1 to the ring 81 of the harness. At this time, the magnet 61 attached to the body and the attachment detection unit 6 of the hook 1 are close to each other, so the attachment detection unit 6 stops the locking state detection unit 3 and does not output a signal indicating whether or not the hook is locked.

When the worker arrives at the work site and begins work, he removes the hook 1 that was engaged with the ring 81 of the harness. This causes the attachment detection unit 6 to separate from the magnet 61, and the detection operation of the engagement state detection unit 3 turns ON. When the worker engages the hook 1 with the engagement portion 8 under these circumstances, the weight of the hook 1 causes it to engage so that it comes into contact with the inner cover 27. During this engagement operation, the engagement portion 8 moves across the optical axis of the engagement state detection unit 3, blocking the light and detecting the "engaged state."

When a "locked state" is detected in this manner, the "locked state" is transmitted to the center device 7 via the transmitter 5 and the wireless terminal device 71.

The center device 7 that receives this signal records the locking state in chronological order, or detects whether the locking pattern is included in a predetermined pattern condition. For example, if the locking state is not detected a reference number of times or more within a predetermined time, it determines that the locking is not performed properly and issues a warning. At this time, if transmission and reception with the center device 7 is performed via a wireless terminal device 71 such as a smartphone, the wireless terminal device 71 is made to sound an alarm.

In this manner, according to the above embodiment, the hook 1 is provided with a hook portion 11 that is engaged with a hooked portion 8 such as a handrail or rope, and an anti-detachment device 14 that can open and close to cover an opening portion for engaging the hook portion 11 with the hooked portion 8 and prevents the hook portion 11 from coming off the hooked portion 8. The hook portion 11 is provided with a cover body 21 that is detachably attached to the hook portion 11 and has a light-emitting unit 31 and a light-receiving unit 32 that detect whether the hook portion 11 is engaged with the hooked portion 8, and a curved hook portion 11 is provided with a light-emitting unit 31 and a light-receiving unit 32 that detect whether the hook portion 11 is engaged with the hooked portion 8. An inner cover 27 is provided that covers the inner edge 12 and has an optical axis hole 34 for the light emitting part 31 and the light receiving part 32 of the cover body 21, and the inner cover 27 is attached to the cover body 21. This means that even if a load or impact is applied, the cover body 21 will not come off the hook part 11. Furthermore, the optical axis hole 34 is provided in the inner cover 27, so that the optical axis holes 33 and 34 can be lengthened to prevent erroneous detection due to the intrusion of external light.

The present invention is not limited to the above embodiment and can be implemented in various ways.

For example, in the above embodiment, the inner cover 27 is engaged using the protrusions 29a and recesses 29b, but it may be engaged in other ways, or a screw hole may be provided in the same position as the screw hole 24 of the cover body 21, and the inner cover 27 and the cover body 21 may be fixed together with the screw 25.

In addition, in the above embodiment, the protective member 35 is provided on the cover body 21, but it may be provided on the optical axis hole 34 of the inner cover 27.

Furthermore, in the above embodiment, the inner cover 27 is made thicker than the cover body 21 to prevent external light from entering from the direction along the optical axis holes 33, 34, but the surface of the cover body 21 or the inner cover 27 may be provided with a protruding portion with a thickness to prevent external light from entering in the direction along the optical axis holes 33, 34.

1: Hook 11: Hook portion 12: Inner edge portion 2: Locking state detection device 21: Cover body 27: Inner cover 29a: Protrusion 29b: Recess 3: Locking state detection portion 31: Light emitting portion 32: Light receiving portion 33, 34: Optical axis hole 35: Protective member

Claims (5)

A hook portion that is engaged with a portion to be engaged such as a handrail or a rope;
a locking device that covers an opening for locking the hook to the locking portion in an openable and closable manner and prevents the hook from coming off the locking portion;
In a locking state detection device attached to a hook comprising:
a cover body that is detachably attached to the hook portion and includes a light emitting unit and a light receiving unit that detect whether the hook portion is engaged with the engaged portion;
an inner cover that covers the curved inner edge of the hook and has optical axis holes for the light emitting unit and the light receiving unit of the cover body ;
The inner cover is attached to the cover body. 2. The locking state detection device according to claim 1, wherein the inner cover is provided so as to cover a surface of the cover body. 2. The locking state detection device according to claim 1, wherein the inner cover is provided with an engaged portion that engages with an engaging portion provided on the surface of the cover body. 2. The locking state detection device according to claim 1, wherein a transparent protective member is provided on the optical axis hole of the cover body or the inner cover. The locking state detection device according to claim 4, in which the protective member is a member having a front and back surface perpendicular to the optical axis.

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