Safety harness hook

Abstract

To provide a hook for a safety belt, enabling smooth opening / closing operation by securing an effective diameter of a hook part and holding rigidity in a front-back direction of an aperture.SOLUTION: A hook 1 for a safety belt includes: a hook-shaped hook body 2 having an engagement side opening 3 on the front; a stopper 4 for directly opening / closing the engagement side opening 3; an opening / closing lever 5 for operating opening / closing of the engagement side opening 3 by interlocking the stopper 4; a lock bar 6 provided from the stopper 4 to the backward side of the hook body 2; and a lock mechanism 7 for controlling sliding of the lock bar 6. The lock bar 6 is fixed by the lock mechanism 7, which makes the lock bar 6 support the stopper 4 at a closed position.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a hook used to fasten a lifeline of a safety belt that prevents a worker from falling to a fixed structure at a high-altitude work site. [Background technology]

[0002] Safety belts worn by workers at high-altitude work sites come in various types, including harnesses and waist belts. All types of safety belts are connected to a lifeline, and a hook attached to the end of the lifeline is fastened to a fixed structure to prevent the worker from falling and ensure safety. In the safety belt hook described in Patent Document 1, a hook capable of locking a stopper is invented to prevent the hook from opening and coming off in an unexpected event.

[0003] Generally, hooks with a similar structure open the opening by gripping the unlocking handle and stopper together with the hook body, and then engage with the structure. Therefore, the user's fingers, which are placed in the middle of the stopper, can block part of the opening, interfering with engaging or detaching the hook from the fixed structure. Patent Document 2 describes a safety belt hook in which the shape of the stopper is curved so that the user's fingers do not get in the way. Patent Document 3 also describes a safety belt hook in which the effective diameter of the hook can be secured by opening and closing the stopper without placing a hand on the stopper itself.

[0004] However, while typical safety ropes used to prevent falls when working at heights are equipped with safety harness hooks with a maximum diameter of 50 mm, there are fixing structures with sizes larger than the maximum diameter of typical safety harness hooks (hereinafter referred to as conventional hooks), such as railway overhead line equipment that uses equal-leg angle irons of 75 mm, and in some cases it is impossible to directly attach conventional hooks.

[0005] Therefore, Patent Document 4 describes a hook for a safety belt that has a large opening dimension, and the stopper can be operated via a link member by operating an opening / closing lever, so that there is no need to grip the stopper itself as with conventional hooks, and the worker's fingers do not block part of the opening on the locking side of the hook. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 7-031687 [Patent Document 2] Japanese Patent Application Laid-Open No. 2007-117573 [Patent Document 3] Japanese Patent Application Publication No. 2017-108822 [Patent Document 4] Japanese Patent Application Publication No. 2020-69125 Summary of the Invention [Problem to be solved by the invention]

[0007] However, the safety belt hook of Patent Document 4 has a problem in that when stress is applied in the front-to-rear direction due to the widened diameter, the rigidity in the front-to-rear direction is insufficient, causing it to bend significantly, making it difficult to open and close smoothly.

[0008] Therefore, the object of the present invention is to provide a hook for a safety belt that ensures the effective diameter of the hook portion and maintains the rigidity of the diameter in the front-to-rear direction when the hook is closed, thereby enabling smooth opening and closing operations. [Means for solving the problem]

[0009] In order to achieve the above object, the invention described in claim 1 is a safety belt hook provided with a hook-shaped hook body having a locking side opening at the front, and a stopper connected to the lower end of the hook body and movable between a closed position where it stands upright to close the locking side opening and an open position where it falls backward to open the locking side opening, and further provided with an opening / closing lever whose lower end is connected to the lower part of the hook body so as to be rotatable in the front-rear direction at a position rearward of the stopper and inside the hook body, a lock bar which extends rearward from the upper end of the stopper towards the hook body at the closed position, and The locking mechanism is provided on the lock body and is switchable between a locked state in which, in the closed position, the locking mechanism engages with the rear end of the locking bar to restrict rearward movement of the locking bar, and an unlocked state in which the locking mechanism does not engage with the rear end of the locking bar and allows rearward movement of the locking bar; the opening / closing lever is connected to the stopper so that the stopper moves in conjunction with the rotation of the opening / closing lever; and when the stopper is moved from the closed position to the open position by the opening / closing lever in the unlocked state of the locking mechanism, the locking bar moves together with the stopper to retreat to the rear side of the engagement side opening. Furthermore, the invention described in claim 2 is characterized in that in the invention described in claim 1, when the stopper moves from the closed position to the open position, the lock bar penetrates the hook body and slides within the hook body, and assumes a position along the hook body at the closed position. Furthermore, the invention described in claim 3 is characterized in that, in the invention described in claim 1 or 2, the opening / closing lever is connected to the stopper via a link member so that the stopper moves in conjunction with the rotation of the opening / closing lever. [Effects of the Invention]

[0010] According to the present invention, a safety belt hook includes a hook-shaped hook body having a locking-side opening, a stopper that directly opens and closes the locking-side opening, an opening / closing lever that moves the stopper, and a locking bar that extends rearward from the upper end of the stopper toward the hook body when the stopper is in the closed position. The locking bar moves to retract toward the rear of the locking-side opening when the stopper moves from the closed position to the open position. Therefore, when the locking-side opening of the safety belt hook is closed, the locking bar is tensioned between the hook body and the stopper in the closed position, thereby increasing the rigidity of the safety belt hook in the front-to-rear direction. Furthermore, when the front of the locking-side opening of the safety belt hook is opened, the locking bar moves to retract toward the rear of the locking-side opening, ensuring a large usable diameter of the locking-side opening without being obstructed by the locking bar. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 10 is a side view of the safety belt hook showing the state in which the locking side opening is closed. [Figure 2] FIG. 10 is a side view of the safety belt hook showing the locking side opening in an open state. [Figure 3] FIG. 2 is a reference diagram in which the grip and the opening / closing lever are omitted from FIG. 1. [Figure 4] FIG. 3 is a reference diagram in which the grip and the opening / closing lever are omitted from FIG. 2. [Figure 5] FIG. 2 is a perspective view of FIG. 1. [Figure 6] FIG. 3 is a perspective view of FIG. 2. [Figure 7] FIG. 10 is a reference enlarged perspective view showing a locking mechanism. DETAILED DESCRIPTION OF THE INVENTION

[0012] An embodiment of the present invention will now be described with reference to the accompanying drawings. Figures 1 and 2 are side views showing a safety belt hook 1 according to the present invention, with Figure 1 showing a state in which the front (right side in the figure) of the locking side opening 3 of the safety belt hook 1 is closed, and Figure 2 showing a state in which the front of the locking side opening 3 of the safety belt hook 1 is open. Also, Figure 3 is a reference view in which the grip 10 and the opening / closing lever 5 are omitted from Figure 1, Figure 4 is a reference view in which the grip 10 and the opening / closing lever 5 are omitted from Figure 2, Figure 5 is a perspective view of Figure 1, and Figure 6 is a perspective view of Figure 2. Also, Figure 7 is a reference enlarged perspective view showing the locking mechanism 7, with (A) showing the locked state and (B) showing the released state.

[0013] As shown in Figures 1 and 2, the safety belt hook 1 has a hook-shaped hook body 2 with a locking side opening 3 at the front, a stopper 4 that directly opens and closes the locking side opening 3, an opening / closing lever 5 that operates the opening and closing of the locking side opening 3 in conjunction with the stopper 4, a lock bar 6 that is provided from the stopper 4 to the rear side of the hook body 2, and a lock mechanism 7 that controls the sliding of the lock bar 6. Here, the position where the stopper 4 closes the locking side opening 3 is referred to as a closed position, and the position where the stopper 4 opens the locking side opening 3 is referred to as an open position.

[0014] As shown in FIG. 3, the hook body 2 has a hook-like shape with a flat top and a locking-side opening 3 at the front, and is a component that is directly engaged with a fixing structure. The hook body 2 is provided with a locking mechanism 7 at the rear center. As shown in FIG. 4, the hook body 2 is provided with a generally U-shaped engaging portion 8 at its front end, which engages with a stopper 4 positioned in the closed position. The hook body 2 also has a connection hole 9 at its front lower portion for attaching a lifeline or the like. The hook body 2 also has fixed shafts 11a, 11b, 11c, and 11d to which various components can be attached. The hook body 2 has an opening / closing lever 5 attached to the fixed shaft 11c, and a stopper 4 attached to the fixed shaft 11d. A generally L-shaped grip 10, which the user holds in their hand during use, is attached integrally to the lower rear portion of the hook body 2 so as to cover the rear of the hook body 2. The grip 10 is fixed by the fixed shafts 11a, 11b, and 11c. Furthermore, a slit (not shown) is formed inside the grip 10 so that the sliding lock bar 6 can retreat.

[0015] The stopper 4 is a generally dogleg-shaped member that can move between a closed position where it stands upright to close the locking-side opening 3 and an open position where it tilts backward to open the locking-side opening 3. The stopper 4 is rotatably connected to the front lower portion of the hook body 2 around a fixed shaft 11d. A torsion spring (not shown) is provided on the fixed shaft 11d, which biases the stopper 4 toward the closed position. As shown in FIGS. 5 and 6 , the stopper 4 has an engaged portion 16 at the front upper end in the closed position, which engages with the engaging portion 8 of the hook body 2. The stopper 4 is connected to the opening / closing lever 5 via a link member 17 rotatably attached to the fixed shaft 11e, and moves in conjunction with the operation of the opening / closing lever 5. The stopper 4 also has fixed shafts 11g and 11f at the rear upper end to which a lock bar 6 is attached.

[0016] The opening / closing lever 5 is a U-shaped member in a side view that is attached to the grip 10 so as to be rotatable about a fixed shaft 11c. The opening / closing lever 5 is connected to the stopper 4 via a link member 17 that is rotatably attached to the fixed shaft 11h. When the opening / closing lever 5 is rotated rearward, the stopper 4 is interlocked with the opening / closing lever 5 via the link member 17, and the stopper 4 is moved between the closed position and the open position.

[0017] The locking bar 6 is a rod-shaped member extending from the stopper 4 to the rear of the hook body 2 in the front-rear direction when the stopper 4 is in the closed position. The front end of the locking bar 6 is fixed to the stopper 4 via fixed shafts 11f and 11g in the closed position, and the locking bar 6 moves in conjunction with the movement of the stopper 4. The locking bar 6 is formed of two plate-shaped members so as to sandwich the locking member 20b (described later) and to be positioned between the locking members 20a (described later). The rear end of the locking bar 6 in the closed position, the tip 18, has a notched portion 18a at the bottom and a thin protrusion at the top. When the stopper 4 moves from the closed position to the open position, the locking bar 6 slides back into the grip 10 in conjunction with the movement of the stopper 4. The locking bar 6 has a curved shape to ensure smooth sliding. The tip 18 is fixed by the lock mechanism 7, thereby restricting the sliding of the lock bar 6. By fixing the lock bar 6 in this way, the lock bar 6 supports the stopper 4 in the closed position.

[0018] The locking mechanism 7 is switchable between a locked state that restricts sliding of the locking bar 6 and an unlocked state that allows sliding of the locking bar 6. As shown in FIG. 7 , the locking mechanism 7 is composed of a locking member 20a that is provided with an unlock button 21 and a slide shaft 22, and a locking member 20b that has a slide hole 23. The locking member 20a is attached to the fixed shaft 11a so that the unlock button 21 protrudes from the top of the grip 10 and so that the slide shaft 22 protrudes forward from the center of the grip 10. The locking member 20b is a member that is integral with the hook body 2 and has an arc-shaped slide hole 23. The positions of the locking members 20a and 20b are determined so that the slide hole 23 supports the slide shaft 22 so that it can move forward and backward. When no external force is applied to the unlock button 21, as shown in Fig. 7(A), the lock member 20a is fixed by a spring (not shown) so that the slide shaft 22 is pressed against the rear end of the slide hole 23. When the unlock button 21 is pressed in, the slide shaft 22 moves to the front of the slide hole 23 as shown in Fig. 7(B).

[0019] Here, a structure for controlling the sliding of the lock bar 6 by the lock mechanism 7 when the stopper 4 is in the closed position will be described. In the safety belt hook 1, the protrusion portion of the tip 18 of the lock bar 6 is configured to be located behind the slide hole 23. When no external force is applied to the unlock button 21, that is, when the lock mechanism 7 is in the locked state, the shaft portion of the slide shaft 22 supports the notch 18a of the tip 18, thereby restricting the rearward sliding of the lock bar 6. When the lock bar 6 is fixed by the lock mechanism 7, it is in a tensioned state between the hook body 2 and the stopper 4 in the closed position.

[0020] When the unlock button 21 is pressed, the slide shaft 22 moves forward in the slide hole 23, which releases the fixation of the tip portion 18 by the slide shaft 22 and allows the lock bar 6 to slide (the lock mechanism 7 is in the released state). When the lock release button 21 is no longer pressed after the lock mechanism 7 is in the released state, the slide shaft 22 is again pressed against the rear end of the slide hole 23 by a spring (not shown), and the tip portion 18 of the lock bar 6 is fixed.

[0021] Next, the operating procedure of the safety belt hook 1 will be explained below. Holding the grip 10 in one's hand, the lock release button 21 is pressed toward the hook body 2 to release the lock mechanism 7 and allow the lock bar 6 to slide. Next, while keeping the lock release button 21 pressed, the opening / closing lever 5 is operated to tilt the lever toward the rear of the hook body 2. When the opening / closing lever 5 is operated, the stopper 4 is linked via the link member 17 and moves to the open position around the fixed shaft 11d. Furthermore, linked to the movement of the stopper 4, the lock bar 6 slides to retract into the inside of the grip 10. In this way, the locking side opening 3 is opened.

[0022] At this time, the stopper 4 moves toward the lower side of the hook body 2, and the lock bar 6 slides to retreat into the grip 10, ensuring a large usable diameter for the locking side opening 3. Furthermore, because the stopper 4 has a concave U-shape that faces inward toward the hook body 2, an even larger diameter can be ensured. In addition, the user's fingers (not shown) holding the opening / closing lever 5 are positioned in the gap V (Fig. 2) between the stopper 4 and the opening / closing lever 5, so the stopper 4 can protect the user's fingers when attaching or detaching the device to or from the fixing structure, and the user's fingers do not get in the way when attaching or detaching the device to or from the fixing structure.

[0023] After the safety belt hook 1 has been attached to or detached from the fixing structure, a torsion spring (not shown) attached to the rotation shaft 11d causes the stopper 4 to rotate forward and stand upright, thereby engaging the engaged portion 16 with the engaging portion 8 of the hook body 2. Finally, by releasing the lock release button 21, the lock mechanism 7 enters the locked state and the lock bar 6 is fixed again. At this time, the safety belt hook 1 is supported in the front-to-rear direction at the center by the lock bar 6, so rigidity in the front-to-rear direction is maintained.

[0024] The safety belt hook 1 of the above embodiment is configured to include a hook-shaped hook body 2 having a locking side opening 3, a stopper 4 that directly opens and closes the locking side opening 3, an opening / closing lever 5 that moves the stopper 4, and a lock bar 6 that extends rearward from the upper end of the stopper 4 toward the hook body 2 when the stopper 4 is in the closed position. The lock bar 6 is configured to move so as to retract toward the rear of the locking side opening 3 when the stopper 4 moves from the closed position to the open position. Therefore, when the locking side opening 3 of the safety belt hook 1 is closed, the lock bar 6 is in a tensioned state between the hook body 2 and the stopper 4 in the closed position, thereby increasing the rigidity of the safety belt hook 1 in the front-to-rear direction. Furthermore, when the front of the locking side opening 3 of the safety belt hook 1 is opened, the lock bar 6 moves so as to retract toward the rear of the locking side opening 3, so that the usable diameter of the locking side opening 3 can be secured without being obstructed by the lock bar 6.

[0025] The present invention has been described above based on the illustrated examples, and the technical scope of the present invention is not limited to these. For example, the material of each part that constitutes the safety belt hook can be freely selected from iron, aluminum, resin, etc., as long as it can ensure the safety of the user.

[0026] Furthermore, the parts constituting the safety belt hook may be made of a single material or multiple materials. Furthermore, the shapes of the components are not limited to those shown in the drawings as long as they can solve the problem at hand. For example, the non-linear stopper may be an arc or trapezoidal shape in addition to the dogleg shape shown as an example. Furthermore, the specific structure and the location of the locking mechanism can be determined arbitrarily as long as it is capable of controlling the sliding of the locking bar, and is not limited to the structure of the embodiment. [Explanation of symbols]

[0027] 1·· Safety harness hook, 2·· Hook body, 3·· Locking side opening, 4·· Stopper, 5·· Opening / closing lever, 6·· Lock bar, 7·· Lock mechanism, 8·· Engaging portion, 9·· Connection hole, 10·· Grip, 11a, 11b, 11c, 11d, 11e, 11f, 11g, 11h·· Fixed shaft, 16·· Engaged portion, 17·· Link member, 18·· Tip portion, 20a, 20b·· Lock member, 21·· Lock release button, 22·· Slide shaft, 23·· Slide hole, V·· Gap.

Claims

1. a hook-shaped hook body having a locking side opening at the front; A safety belt hook is provided with a stopper connected to the lower end of the hook body, which is movable between a closing position where it stands upright to close the locking side opening and an opening position where it leans backward to open the locking side opening, an opening / closing lever whose lower end is connected to the lower part of the hook body so as to be rotatable in the front-rear direction, at a position rearward of the stopper and inside the hook body; a lock bar extending rearward from an upper end of the stopper toward the hook body at the closed position; a locking mechanism provided on the hook body, which is switchable between a locked state in which the locking mechanism engages with the rear end of the locking bar to restrict rearward movement of the locking bar at the closed position and a released state in which the locking mechanism does not engage with the rear end of the locking bar and allows rearward movement of the locking bar; the opening / closing lever is connected to the stopper so that the stopper moves in conjunction with the rotation of the opening / closing lever; When the stopper is moved from the closed position to the open position by the opening / closing lever while the locking mechanism is in the released state, the lock bar moves together with the stopper to retreat toward the rear side of the engaging side opening.

2. The safety belt hook according to claim 1, characterized in that, when the stopper moves from the closed position to the open position, the lock bar penetrates the hook body and slides inside the hook body, and assumes a posture along the hook body at the closed position.

3. 3. The safety belt hook according to claim 1, wherein the opening / closing lever is connected to the stopper via a link member so that the stopper moves in conjunction with the rotation of the opening / closing lever.

Images