Guardrail beam attachment / detachment aid jig

Abstract

To provide a jig for assisting in attaching and detaching a guardrail beam, which can securely lock the jig to a bracket and reliably support the guardrail beam without causing it to fall when the guardrail beam is attached or detached. [Solution] The guardrail beam attachment / detachment assist jig 10 of this invention is equipped with a beam holding part that houses the guardrail beam 11, two bracket locking rods 2 (including a rotating locking rod and a fixed locking rod) that lock onto brackets 12, locking pieces 3 provided at the ends of the rods 2, and a movable part for rotating or pivoting the rods 2. In this invention, it is preferable that the bracket locking rods 2 are rotatably supported by the movable part.

Description

[Technical Field]

[0001] This invention relates to a guardrail beam attachment / detachment assist jig, which is a tool that can temporarily hold a guardrail beam with a bracket when attaching or detaching the guardrail beam to a guardrail post with a bracket fixed thereto. [Background technology]

[0002] Guardrail beams, which are horizontally extending members of a guardrail, weigh approximately 60 kg to 120 kg each and are approximately 2 m to 4 m long, depending on their specifications. While mechanized methods exist for driving guardrail posts into place or pulling them out, workers typically manually install and remove guardrail beams from brackets, making precise adjustments. However, as mentioned above, because guardrail beams are heavy, when attaching or removing a guardrail beam to a bracket, multiple workers (e.g., four workers) support the guardrail beam while another worker aligns the bolt holes in the bracket attached to the support with the bolt holes in the guardrail beam and secures it with special bolts (fixing bolts). Therefore, when attaching a guardrail beam, multiple workers must manually support the guardrail beam until the bolt holes on the guardrail beam are aligned with the bolt holes on the support, and the fixing bolts are inserted and secured, requiring a physically exhausting and labor-intensive task. Similarly, when removing the guardrail beam from the bracket, the guardrail beam must be securely supported. Furthermore, if the fixing bolts connecting the bracket and guardrail beam loosen, the guardrail beam could fall onto a worker's feet, potentially resulting in injury.

[0003] When attaching or detaching a guardrail beam to a bracket, there is a conventional technique in which a roughly S-shaped jig is engaged at a position near the support or bracket, and the guardrail beam is placed on the jig to hold the guardrail beam in a predetermined position near the bracket (see Prior Art Document 1). However, this prior art (Prior Art Document 1) requires a single, roughly S-shaped jig to support the guardrail beam, raising questions about the reliability of the support. Furthermore, depending on the relative positions of the roughly S-shaped jig and the bracket, the jig may not be securely fastened to the bracket when holding the guardrail beam. If the guardrail beam is not securely fastened, the jig holding the guardrail beam may come off the support or bracket and fall. Furthermore, depending on the relative positions of the roughly S-shaped jig and the bracket, the jig may interfere with the guardrail beam when it is locked, potentially damaging the guardrail beam. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 3852860 Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention was proposed in consideration of the problems of the prior art described above, and aims to provide a guardrail beam installation and removal assist jig that can be securely engaged with the bracket and reliably support the guardrail beam without it falling when installing or removing it. [Means for solving the problem]

[0006] The guardrail beam attachment / detachment assist jig (10, 10-1) of the present invention is characterized by having a beam holding portion (1) that accommodates the guardrail beam (11), two bracket engagement rods (2, 2-1: including the pivoting side engagement rod 2-1B and the fixed side engagement rod 2-1A) that engage with the bracket (12), engagement pieces (3, 3-1) provided at the ends of the rods (2, 2-1), and a movable portion (4, 4-1) for rotating or pivoting the rods (2, 2-1). In this specification, the rotating side locking rod 2-1B and the fixed side locking rod 2-1A may be denoted by the symbol 2-1. Also, in this specification, the locking pieces 3-1A and 3-1B may be collectively referred to as "locking pieces 3-1."

[0007] In the present invention, it is preferable that the bracket locking rod (2) is rotatably supported by the movable part (4).

[0008] Alternatively, the two bracket locking rods (2-1) are preferably a fixed side locking rod (2-1A) that is fixed without changing its relative position with respect to the beam holding part (1), and a rotating side locking rod (2-1B) that is supported by the movable part (4-1) so that it can swing (rotate).

[0009] Furthermore, the guardrail beam attachment / detachment assist jig (10-2) of the present invention comprises a beam holding portion (1) that accommodates the guardrail beam (11), a bracket locking rod (2-2) having a bracket locking portion (2-2H) that can be placed on the upper end surface of the bracket (12), and a detachment prevention rod (3-4) that is rotatable and can engage with the bracket locking portion (2-2H). The device is characterized in that an opening (3S) is provided on the side where the slip-off prevention rod (3-4) is provided.

[0010] The method of installing a guardrail beam of the present invention using the above-mentioned guardrail beam installation / removal assist jig (10: guardrail beam installation / removal assist jig of claim 2: first embodiment) is as follows: a step of moving the jig (10) from below the bracket (12) and positioning the guardrail beam attachment / detachment assist jig (10) so that the locking piece (3) at the upper end of the bracket locking rod (2) is slightly above the locking portion (12A) of the bracket (12); The method includes a step of rotating the bracket locking rod (2) to position the locking piece (3) so that it is locked to the locking portion (12A) of the bracket (12) (placed on the locking portion 12A of the bracket 12). In the above method, the guardrail beam (11) is placed in the beam holding portion 1 of the jig 10, the bolt through-holes (12B) of the bracket (12) are aligned with the bolt through-holes of the guardrail beam (11), and the beam mounting bolts (14) are inserted and fastened, thereby attaching the guardrail beam (11) to the bracket (12).

[0011] In addition, a method for removing a guardrail beam using the guardrail beam attachment / detachment assisting jig described above (10: guardrail beam attachment / detachment assisting jig of claim 2: first embodiment) is as follows: a step of inserting the bracket locking rod (2) into the space between the guardrail beam (11) and the support (13) (the space behind the guardrail beam 11) while storing the guardrail beam (11) in the beam holding portion (1) so that the locking piece (3) at the upper end of the bracket locking rod (2) is slightly above the locking portion (12A) of the bracket (12); The method includes a step of rotating the bracket locking rod (2) to lock (place) the locking piece (3) on the locking portion (12A) of the bracket (12). In the above method, by removing the beam mounting bolts (14), the fixed state of the guardrail beam (11) and the bracket (12) can be released.

[0012] The method of attaching a guardrail beam using the guardrail beam attachment / detachment assisting jig described above (10-1: guardrail beam attachment / detachment assisting jig of claim 3: second embodiment) is as follows: a step of placing the guardrail beam attachment / detachment assisting jig (10-1) near the bracket (12) with the pivoting side locking rod (2-1B) open, and locking the locking piece (3-1A) of the fixed side locking rod (2-1A) to the locking portion (12A) of the bracket (12); The method includes a step of closing the pivot-side locking rod (2-1B) to lock the locking piece (3-1B) of the pivot-side locking rod (2-1B) onto the locking portion (12A) of the bracket (12). In the above method, the guardrail beam (11) can be attached to the bracket (12) by aligning the bolt through-hole (12B) of the bracket (12) with the bolt through-hole of the guardrail beam (11) and inserting and fastening the beam mounting bolt (14) therein.

[0013] In addition, a method for removing a guardrail beam using the guardrail beam attachment / detachment assisting jig described above (10-1: guardrail beam attachment / detachment assisting jig of claim 3: second embodiment) is as follows: a step of inserting the open pivot-side locking rod (2-1B) and the fixed-side locking rod (2-1A) into the space behind the guardrail beam (11) while storing the guardrail beam (11) in the beam holding portion (1), and locking the locking piece (3-1A) of the fixed-side locking rod (2-1A) with the locking portion (12A) of the bracket (12); The method includes a step of closing the pivot-side locking rod (2-1B) and locking (placing) the locking piece (3-1B) of the pivot-side locking rod (2-1B) to the locking portion (12A) of the bracket (12). In the above method, the guardrail beam can be removed by removing the beam mounting bolts (14) and releasing the fixed state of the guardrail beam (11) from the bracket (12).

[0014] A method of attaching a guardrail beam using the guardrail beam attachment / detachment assisting jig described above (10-2: guardrail beam attachment / detachment assisting jig of claim 4: third embodiment) is as follows: a step of inserting a guardrail beam attachment / detachment assist jig (10-2) from the side of the bracket (12) (from the direction of arrow R30) from the opening (3S) side into a portion of the bracket (12) to which the guardrail beam (11) is not attached, with the removal prevention rod (3-4) not engaged with the bracket locking portion (2-2H) (open state); a step of placing the bracket engaging portion (2-2H) of the guardrail beam attachment / detachment assisting jig (10-2) on the upper end surface of the bracket (12); The method includes a step of engaging (closing) the detachment prevention rod (3-4) with the bracket locking portion (2-2H). In the above method, the guardrail beam (11) is placed in the beam holding portion (1) of the jig (10-2), the bolt through-holes (12B) of the bracket (12) are aligned with the bolt through-holes of the guardrail beam (11), and the beam mounting bolts (14) are inserted and fastened thereto, thereby attaching the guardrail beam (11) to the bracket (12).

[0015] In addition, a method for removing a guardrail beam using the guardrail beam attachment / detachment assisting jig described above (10-2: guardrail beam attachment / detachment assisting jig of claim 4: third embodiment) is as follows: a step of inserting a guardrail beam attachment / detachment assist jig (10-2) from the side of the bracket (12) (from the direction of arrow R30) into the portion of the bracket (12) to which the guardrail beam (11) is attached from the opening (3S) side, with the removal prevention rod (3-4) not engaged with the bracket locking portion (2-2H) (open state); a step of placing the bracket locking portion (2-2H) of the guardrail beam attachment / detachment assisting jig (10-2) on the upper end surface of the bracket (12) and positioning the guardrail beam (11) on the beam holding portion (1) of the guardrail beam attachment / detachment assisting jig (10-2); The method includes a step of engaging (closing) the detachment prevention rod (3-4) with the bracket locking portion (2-2H). In the above method, the fixed state of the guardrail beam (11) and the bracket (12) can be released by removing the beam mounting bolt (14) that fastens the guardrail beam (11) housed in the beam holding portion (1) to the bracket (12). [Effects of the Invention]

[0016] According to the present invention having the above-mentioned configuration, the locking pieces (3, 3-1) of the bracket locking rods (2, 2-1: including the pivoting side locking rod 2-1B and the fixed side locking rod 2-1A) of the guardrail beam attachment / detachment assist jig (10, 10-1) are locked (placed) on the locking portions (12A) of the brackets (12). Therefore, when the guardrail beam (11) is accommodated in the beam holding portion (1), the weight of the guardrail beam (11) is reliably supported by the support (13) to which the bracket (12) is fixed, via the beam holding portion (1), the locking pieces (3, 3-1), and the locking portions (12A) of the brackets (12). Therefore, when installing or removing the guardrail beam (11), if the guardrail beam (11) is stored in the beam holding portion (1), the jig (10, 10-1) will not come off the bracket (12) when placed, and the guardrail beam (11) will not fall when placed. In addition, the bracket locking rods (2, 2-1, 2-1A) of the guardrail beam attachment / detachment assist jigs (10, 10-1) are locked to the brackets (12), so the guardrail beams (11) and the jigs (10, 10-1) do not interfere with each other, preventing damage to the guardrail beams (11).

[0017] In addition, according to the present invention, by providing the movable parts (4, 4-1), when attaching or detaching the guardrail beam (11), the locking pieces (3, 3-1) are locked (placed) on or unlocked from the locking parts (12A) of the bracket (12) without the guardrail beam attachment / detachment assist jig (10, 10-1) interfering with the support (13) and the bracket (12). Furthermore, the locking pieces (3, 3-1) of the two bracket locking rods (2, 2-1: including the rotating side locking rod 2-1B and the fixed side locking rod 2-1A) are locked (placed) on both ends of the locking portion (12A) of the bracket (12) (both longitudinal ends of the guardrail beam 11: both left and right ends in Figures 1, 16, and 18). This makes it more difficult for the guardrail beam attachment / detachment assist jig (10, 10-1) to come off the bracket (12) compared to the prior art (Patent Document 1) in which the jig is locked to the support at only one point. This prevents the guardrail beam attachment / detachment assist jig (10, 10-1) from coming off the bracket (12) and falling at a timing unexpected by the worker, thereby improving the safety of the worker when attaching or detaching the guardrail beam (11).

[0018] Furthermore, according to the guardrail beam attachment / detachment assist jig (10-2) of the present invention, the bracket engagement portion (2-2H) is placed on the upper end surface of the engagement portion 12A of the bracket (12), so that the weight of the guardrail beam (11) accommodated in the beam holding portion (1) (accommodation portion R) of the guardrail beam attachment / detachment assist jig (10-2) is reliably supported by the bracket (12) (upper end surface of the engagement portion 12A) via the guardrail beam attachment / detachment assist jig (10-2). Furthermore, it has a rotatable anti-detachment rod (3-4) that can engage with the bracket locking portion (2-2H), and an opening (3S) is provided on the side where the anti-detachment rod (3-4) is provided, so that by opening the anti-detachment rod (3-4), the guardrail beam attachment / detachment assist jig (10-2) can be inserted into the bracket (12). Then, by rotating the anti-detachment rod (3-4) and engaging it with the bracket locking portion (2-2H), the guardrail beam attachment / detachment assist jig (10-2) is prevented from coming off the bracket (12) when installing or removing the guardrail beam (11).

[0019] According to the method of installing or removing a guardrail beam using the guardrail beam installation / removal assist jig (10-2) of the present invention, the bracket locking portion (2-2H) is placed on the upper end surface of the locking portion (12A) of the bracket (12), so the weight of the guardrail beam (11) housed in the beam holding portion (1) of the guardrail beam installation / removal assist jig (10-2) is reliably supported by the bracket (12). Therefore, once the guardrail beam (11) is housed in the housing portion (R), the guardrail beam (11) can be reliably held by the guardrail beam installation / removal assist jig (10-2) without the need for multiple workers. Therefore, by connecting (for example, bolting) the bracket (12) and the guardrail beam (11) while the guardrail beam (11) is supported by the guardrail beam attachment / detachment assist jig (10-2), the guardrail beam (11) can be firmly attached to the bracket (12) without the need for multiple workers to hold the guardrail beam (11). Alternatively, by using the guardrail beam attachment / detachment assist jig (10-2) to make the guardrail beam (11) supportable and releasing the connection (e.g., bolt fastening) of the guardrail beam (11) connected to the bracket (12), the guardrail beam (11) can be easily removed from the bracket (12) without the need for multiple workers to hold the guardrail beam (11). [Brief explanation of the drawings]

[0020] [Figure 1] 1 is a front view of a first embodiment of a guardrail beam installation / removal assist jig according to the present invention. FIG. [Figure 2] FIG. 2 is a rear view of the first embodiment. [Figure 3] FIG. 1 is a side view of the first embodiment. [Figure 4] FIG. 4 is a side view of the first embodiment, showing a state in which the bracket locking rod has been rotated 90° from the state in FIGS. 1 to 3 and is no longer locked with the locking portion of the bracket. [Figure 5]FIG. 10 is an explanatory diagram of the rotation prevention mechanism of the bracket locking rod, showing the state immediately before the bracket locking rod is prevented from rotating. [Figure 6] FIG. 6 is an explanatory diagram of the anti-rotation mechanism of the bracket locking rod similar to FIG. 5, showing a state in which the bracket locking rod is prevented from rotating. [Figure 7] 1 is a side view showing a guardrail support, a bracket, and a guardrail beam to which the guardrail beam attachment / detachment assisting jig of the present invention is applied. [Figure 8] FIG. 8 is a plan view showing the guardrail support, bracket, and guardrail beam shown in FIG. 7. [Figure 9] FIG. 10 is a front view showing the state in which the guardrail beam attachment / detachment assisting jig of the first embodiment is adjacent to the bracket but not locked when attaching the guardrail beam. [Figure 10] FIG. 10 is a side view of the state shown in FIG. [Figure 11] 11 is an enlarged explanatory view showing the relative positions of the locking pieces of the guardrail beam attachment / detachment assisting jig and the locking portions of the bracket in the states of FIGS. 9 and 10. FIG. [Figure 12] 11 is a front view showing a state in which the bracket locking rod is rotated from the state shown in FIG. 10 to lock the locking piece to the locking portion of the bracket. FIG. [Figure 13] 13 is an enlarged explanatory view showing the relative positions of the locking pieces of the guardrail beam attachment / detachment assisting jig and the locking portions of the bracket in the state shown in FIG. 12. [Figure 14] 10 is a front view showing the guardrail beam attachment / detachment assisting jig of the first embodiment adjacent to the bracket but not locked when removing the guardrail beam. FIG. [Figure 15] 15 is a front view showing a state in which the bracket locking rod is rotated from the state shown in FIG. 14 to lock the locking piece to the locking portion of the bracket. FIG. [Figure 16] FIG. 10 is a front view of a second embodiment of the guardrail beam installation / removal assist jig of the present invention, showing the state in which the beam locking rod on the pivoting side is open. [Figure 17] FIG. 10 is a side view of the second embodiment. [Figure 18] FIG. 10 is a front view of the second embodiment, showing a state in which the beam locking rod on the rotation side is closed. [Figure 19] This is a front view showing the state in which the guardrail beam attachment / detachment assist jig of the second embodiment is adjacent to the bracket when installing the guardrail beam, but the beam locking rod on the rotating side is open and not locked. [Figure 20] 20 is a front view showing a state in which the beam locking rod on the pivot side is closed and the locking piece is locked to the locking portion of the bracket, following the state shown in FIG. 19. FIG. [Figure 21] This is a front view showing the state in which the guardrail beam attachment / detachment assist jig of the second embodiment is adjacent to the bracket when removing the guardrail beam, but the beam locking rod on the rotating side is open and not locked. [Figure 22] 22 is a front view showing a state in which the beam locking rod on the pivot side is closed and the locking piece is locked to the locking portion of the bracket, following the state shown in FIG. 21. FIG. [Figure 23] 10 is a perspective view of a third embodiment of the guardrail beam installation / removal assist jig of the present invention, showing the state in which the removal prevention rod is open. [Figure 24] FIG. 10 is a front view of the third embodiment in a state where the removal prevention rod is open. [Figure 25] FIG. 10 is a plan view of the third embodiment in a state where the removal prevention rod is open. [Figure 26] FIG. 10 is a side view of the third embodiment in a state where the removal prevention rod is open. [Figure 27] FIG. 10 is a front view of the third embodiment showing the state in which the removal prevention rod is closed. [Figure 28] FIG. 10 is a plan view of the third embodiment showing the state in which the removal prevention rod is closed. [Figure 29] FIG. 10 is a side view of the third embodiment showing the state in which the removal prevention rod is closed. [Figure 30]10 is a plan view showing the state in which a guardrail beam attachment / detachment assisting jig according to the third embodiment is placed on a bracket and a support post when attaching a guardrail beam. FIG. [Figure 31] FIG. 31 is a front view of the state shown in FIG. 30. [Figure 32] FIG. 32 is a side view of the state shown in FIGS. 30 and 31. [Figure 33] FIG. 33 is a plan view showing the state in which the guardrail beam attachment / detachment assisting jig according to the third embodiment is attached to the bracket and the support pillar with the removal prevention rod closed in FIGS. 30 to 32. [Figure 34] FIG. 34 is a side view of the state shown in FIG. 33. [Figure 35] FIG. 35 is a front view showing a state in which the beam is housed in the beam holding section in FIGS. 33 and 34. [Figure 36] FIG. 36 is a side view of the state shown in FIG. [Figure 37] 10 is a plan view showing a state in which a guardrail beam attachment / detachment assisting jig according to a third embodiment is placed on a bracket to which a guardrail beam is attached when the guardrail beam is to be removed. FIG. [Figure 38] FIG. 38 is a side view of the state shown in FIG. 37. DETAILED DESCRIPTION OF THE INVENTION

[0021] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. First, a first embodiment of the present invention will be described with reference to FIGS. Figures 1 to 4 show a guardrail beam attachment / detachment assist jig 10 relating to the first embodiment. In Figure 1, the guardrail beam attachment / detachment assist jig 10 has a beam holding portion 1, two (pairs of) bracket locking rods 2, locking pieces 3 provided at the tip of each bracket locking rod 2, and a movable portion 4 provided on each bracket locking rod 2 to rotate or pivot the bracket locking rod 2 about an axis. As shown in Figures 1 to 4, the beam holding portion 1 has a storage portion R (see Figures 3 and 4) provided continuously below each bracket locking rod 2 (in Figures 1 to 4), and when the guardrail beam is attached or detached, the guardrail beam 11 (not shown in Figures 1 to 4: see Figures 7, 8, 14, and 15) is stored in the space within the storage portion R. The storage portion R has the beam holding portion 1, a beam-like member 1H extending horizontally, and a connecting portion 2B (described later), and the beam-like member 1H and connecting portion 2B are provided at the same position in the vertical direction.

[0022] 1 to 4, a movable part 4 is provided at the boundary or connection between the bracket locking rod 2 and the housing part R that constitutes the beam holding part 1. The movable part 4 is a hollow sleeve-shaped member, and in the internal space of the movable part 4, the bracket locking rod 2 is supported so as to be rotatable around the central axis of the rod 2. Each of the left and right bracket locking rods 2 in FIG. 1 is connected to a connecting part 2B at the movable part 4. A rotation prevention mechanism for the bracket locking rod 2 is provided at the lower end of the movable part 4. The locking piece 3 is configured by bending at a substantially right angle from the upper end of the bracket locking rod 2. In other words, the bracket locking rod 2 and the locking piece 3 are configured as a substantially L-shape as a whole. When the bracket locking rod 2 is rotated by the movable part 4 (arrow A), the locking piece 3 rotates and assumes the state shown in Figures 1 to 3 or the state shown in Figure 4. 1 to 3, the locking pieces 3 face inward (the left-right direction in FIG. 1, toward the inside of the guardrail beam attachment / detachment assist jig 10), and the locking pieces 3 in the states of FIGS. 1 to 3 can be placed on the locking portions 12A of the bracket 12 (see FIGS. 8, 11, 13, etc.). On the other hand, in the state of FIG. 4, the locking pieces 3 do not face inward (the direction in which the locking pieces 3 face in FIGS. 1 to 3), but face in a direction perpendicular to the paper surface in FIG. 1, toward the side away from the viewer (the back side of the guardrail beam 11, not shown in FIG. 4). The locking pieces 3 in the state shown in FIG. 4 cannot be placed on the locking portions 12A of the bracket 12 (see FIGS. 8, 11, 13, etc.). The relative positional relationship between the locking pieces 3 and the locking portions 12A of the bracket 12 will be described later with reference to FIGS. 11 and 13.

[0023] An end 2E of the bracket locking rod 2 opposite the locking piece 3 is bent in a different direction from the locking piece 3. The bent end 2E of the bracket locking rod 2 and a notch 4R formed below the hollow sleeve-shaped movable part 4 form a rotation prevention mechanism for the bracket locking rod 2. This rotation prevention mechanism will be described with reference to Figures 5 and 6. 5 and 6, a stopper S is fixed to the beam holding part 1. In Fig. 5, the bent end 2E of the bracket locking rod 2 abuts against the stopper S and does not move further downward. In the state of Fig. 5, the bracket locking rod 2 is not prevented from rotating, and the bent end 2E is not accommodated in the notch 4R of the movable part 4. When the bracket locking rod 2 moves in the direction of arrow U (upward in Figure 5) from the state in Figure 5, it reaches the state shown in Figure 6, where the bent end 2E of the bracket locking rod 2 is housed in the notch 4R and is unable to rotate (locked state). Here, the state in which the end 2E is housed in the notch 4R is the state shown in Figures 1 to 3, and the locking piece 3 is placed on the locking portion 12A of the bracket 12, as will be described later with reference to Figure 13.

[0024] 7 and 8, which show a guardrail 20 to which guardrail beam attachment / detachment assist jigs 10, 10-1 according to the illustrated embodiment are applied, the guardrail 20 includes a support post 13, a plate-shaped guardrail beam 11, a bracket 12 for attaching the guardrail beam 11 to the support post 13, a beam attachment bolt 14 for fastening the guardrail beam 11 to the bracket 12, and a bracket attachment bolt 15 for fastening the bracket 12 to the support post 13 (FIG. 7). The guardrail beam 11 is a plate-shaped member with a bent cross section, and extends in a direction perpendicular to the plane of the paper in FIG. 7 and in a left-right direction in FIG. 8. Note that in FIG. 8, only a portion of the guardrail beam 11 is shown for the sake of simplicity. Bracket 12, shown by dotted lines in Fig. 8, has portion 12E extending parallel to guardrail beam 11 and substantially M-shaped portion 12D, and substantially M-shaped portion 12D has locking portion 12A of bracket 12. In Fig. 8, locking portion 12A forms a pair of legs extending from support 13 toward guardrail beam 11 in substantially M-shaped portion 12D. 7 and 8, when attaching a new guardrail beam 11 to the bracket 12, the bolt through-holes (not shown in FIGS. 7 and 8) of the bracket 12 attached to the support 13 are aligned with the bolt through-holes (not shown in FIGS. 7 and 8) of the guardrail beam 11, and the beam attachment bolts 14 are inserted and fastened. The bracket 12 and support 13 are fixed with the bracket attachment bolts 15.

[0025] 9 to 13, the work of attaching a new guardrail beam 11 to a bracket 12 using the guardrail beam attachment / detachment assist jig 10 shown in FIGS. 1 to 4 (the guardrail beam attachment / detachment assist jig 10 according to the first embodiment) will be described. 9 and 10, first, the guardrail beam attachment / detachment assist jig 10 is moved in the direction of arrow B from below the bracket 12, and positioned so that the upper end of the bracket locking rod 2 (the position of the locking piece 3) is slightly above the locking portion 12A of the bracket 12. In the state shown in FIGS. 9 and 10, the locking piece 3 of the bracket locking rod 2 is not placed on the locking portion 12A of the bracket 12 (the state shown in FIG. 11), and the locking piece 3 and the locking portion 12A are not locked to each other. In other words, when the locking piece 3 of the bracket locking rod 2 and the locking portion 12A of the bracket 12 shown in FIGS. 9 and 10 are not locked to each other, the relative positions of the locking piece 3 and the locking portion 12A are as shown in FIG. 11. In FIG. 11, the locking piece 3 and the locking portion 12A do not overlap, so they are not locked to each other. Therefore, when the guardrail beam attachment / detachment assist jig 10 is moved in the direction of arrow B (Figures 9 and 10) from below the bracket 12, the locking piece 3 of the bracket locking rod 2 does not interfere with the locking portion 12A of the bracket 12, and the guardrail beam 11 is not damaged, so the guardrail beam attachment / detachment assist jig 10 can be easily moved to the designated position. 7 and subsequent figures, components other than the guardrail beam attachment / detachment assist jig 10 are shown in dashed lines. In addition, in Figures 9, 10, and 11, the guardrail beam 11 is not shown because it is in a state before attachment.

[0026] 9 to 11, the bracket locking rod 2 is rotated (in the direction of arrow A in FIGS. 1 to 4) to position the locking piece 3 so that it is placed on the locking portion 12A of the bracket 12, as shown in FIGS. 12 and 13. As a result, in the plan view of FIG. 13, the locking piece 3 of the bracket locking rod 2 and the locking portion 12A of the bracket 12 are positioned so that they overlap each other, and the locking piece 3 is locked to the locking portion 12A. When the locking piece 3 is locked (placed) on the locking portion 12A of the bracket 12, even if the guardrail beam 11 (not shown in Figure 12) is stored in the beam holding portion 1 of the guardrail beam attachment / detachment assist jig 10 in Figure 12, the weight of the guardrail beam 11 is securely supported by the bracket 12 via the beam holding portion 1, the locking piece 3 of the bracket locking rod 2, the locking portion 12A of the bracket 12, and the beam mounting bolt 14 (Figure 7). That is, if the guardrail beam 11 is stored in the beam holding portion 1 of the guardrail beam attachment / detachment assist jig 10 that is engaged with the bracket 12 to which the guardrail beam 11 is to be attached, the guardrail beam 11 can be held by the guardrail beam attachment / detachment assist jig 10 without the need for multiple workers. In addition, with the guardrail beam attachment / detachment assist jig 10, the locking pieces 3 are engaged with the locking portions 12A at two locations, left and right, as shown in Figure 12, so the jig 10 will not come off the bracket 12 and will not fall with the guardrail beam 11 placed on it, and the guardrail beam 11 can be supported. Then, with the guardrail beam 11 supported by the guardrail beam attachment / detachment assist jig 10, the bolt through-hole 12B (Figure 12) of the bracket 12 is aligned with the bolt through-hole (not shown) of the guardrail beam 11, and the beam mounting bolt 14 (Figure 7) is inserted and fastened thereto, thereby attaching the guardrail beam 11 to the bracket 12. In FIG. 12, reference numeral 12C denotes a hole drilled in the center of the bracket 12.

[0027] In the first embodiment, the guardrail beam attachment / detachment assisting jig 10 is moved in the direction of arrow B (FIGS. 9 and 10) from below the bracket 12, and the locking piece 3 of the bracket locking rod 2 is positioned slightly above the locking portion 12A of the bracket 12, (As shown by arrow A in Figures 1 to 4), rotate the bracket locking rod 2 so that the position of the locking piece 3 is placed on the locking portion 12A of the bracket 12 (or, as shown in Figures 12 and 13, place the locking piece 3 on the locking portion 12A of the bracket 12 so that it overlaps with the locking portion 12A). By this simple operation, the weight of the guardrail beam 11 can be reliably supported by the bracket 12. 12, when the locking pieces 3 of the left and right bracket locking rods 2 are placed on both ends of the locking portions 12A of the bracket 12 (both longitudinal ends of the guardrail beam 11, not shown), and the locking pieces 3 are locked to the locking portions 12A of the bracket 12, the guardrail beam attachment / detachment assist jig 10 and the bracket 12 are locked at two points. Therefore, compared to the prior art (Patent Document 1) in which the jig is locked to the support post at only one point, the jig 10 is less likely to come off the bracket 12. Therefore, according to the first embodiment, the possibility that the guardrail beam attachment / detachment assist jig 10 will come off the bracket 12 at a timing unexpected by the worker is greatly reduced, improving the safety of the worker during the installation work of the guardrail beam 11.

[0028] 14 and 15, the operation of removing the guardrail beam 11 from the bracket 12 using the guardrail beam attachment / detachment assisting jig 10 according to the first embodiment will be described. In Figure 14, first, the guardrail beam 11 is housed in the beam holding portion 1 of the beam attachment / detachment assist jig 10. Then, the beam attachment / detachment assist jig 10 is moved in the direction of arrow B from the back side of the guardrail beam 11 in Figure 14 (the side perpendicular to the paper surface in Figure 14 and away from the viewer). The movement in the direction of arrow B is carried out so that the upper end (locking piece 3) of the bracket locking rod 2 inserted into the space between the guardrail beam 11 and the support 13 (the space behind the guardrail beam 11 in Figure 14) is slightly above the locking portion 12A of the bracket 12. In the state shown in Figure 14, the locking piece 3 of the bracket locking rod 2 is not placed on the locking portion 12A of the bracket 12 (the locking piece 3 is not locked to the locking portion 12A of the bracket 12), and the relative positional relationship between the locking piece 3 of the bracket locking rod 2 and the locking portion 12A of the bracket 12 is as shown in Figure 11. Therefore, when the bracket locking rod 2 moves in the direction of arrow B, the bracket locking rod 2 does not interfere with the bracket 12 and does not damage the guardrail beam 11.

[0029] The bracket locking rod 2 is rotated from the state shown in Fig. 14 (as shown by arrow A in Figs. 1 to 4) to a position shown in Fig. 15 where the locking piece 3 is placed on the locking portion 12A of the bracket 12 as shown in Fig. 13. As a result, the locking piece 3 of the bracket locking rod 2 is placed on the locking portion 12A of the bracket 12, and the locking piece 3 is locked to the locking portion 12A. As shown in Figure 15, when the locking pieces 3 of the left and right bracket locking rods 2 are locked to the locking portions 12A of the brackets 12, the weight of the guardrail beam 11 is securely supported by the brackets 12 via the beam holding portions 1, the locking pieces 3, and the locking portions 12A of the brackets 12, even if the beam mounting bolts 14 (see Figure 7: not shown in Figure 15) are removed.

[0030] In the state shown in Figure 15, even if the beam mounting bolts 14 (see Figure 7; not shown in Figure 15) are removed, the weight of the guardrail beam 11, which is a heavy object, is securely supported by the bracket 12, so even if multiple workers do not hold and support the guardrail beam 11, the guardrail beam attachment / detachment assist jig 10 will not come off the bracket 12, and the guardrail beam 11 will not fall along with the jig 10, and the guardrail beam 11 can be maintained in a position adjacent to the bracket 12. Then, the beam mounting bolts 14 are removed to release the fixed state between the guardrail beam 11 and the bracket 12. In this way, by using the guardrail beam attachment / detachment assisting jig 10 according to the first embodiment, when removing the guardrail beam 11 from the bracket 12, The guardrail beam 11 is accommodated in the beam holding portion 1, and the bracket locking rod 2 is inserted into the space behind the guardrail beam 11. The bracket locking rod 2 is rotated so that the locking piece 3 is placed on the locking portion 12A of the bracket 12. With this simple operation, the weight of the guardrail beam 11 can be reliably supported by the bracket 12. Furthermore, the guardrail beam attachment / detachment assist jig 10 will not come off the bracket 12 at a timing that the worker does not expect, improving the safety of the worker when removing the guardrail beam 11.

[0031] Next, a second embodiment of the present invention will be described with reference to Figures 16 to 22. In Figures 16 to 22, the same components as those in the first embodiment are denoted by the same reference numerals. 16 to 18 show a guardrail beam attachment / detachment assisting jig 10-1 according to the second embodiment. 16, guardrail beam attachment / detachment assist jig 10-1 has beam holding part 1, left and right bracket locking rods 2-1A and 2-1B (fixed-side locking rod 2-1A and rotating-side locking rod 2-1B), locking pieces 3-1A and 3-1B provided at the respective ends of fixed-side locking rod 2-1A and rotating-side locking rod 2-1B, and movable part 4-1 that swings or rotates rotating-side locking rod 2-1B. Here, the left bracket locking rod 2-1A in FIGS. 16 and 18 may be referred to as fixed-side locking rod 2-1A, and the right bracket locking rod 2-1B may be referred to as rotating-side locking rod 2-1B. 16 and 18, the bracket locking rod 2-1B (rotating side locking rod) on the right side is rotatably supported by the movable part 4-1, and swings or rotates as shown by arrow C in FIGS. 16 and 18. On the other hand, the bracket locking rod 2-1A (fixed side locking rod) on the left side in FIGS. 16 and 18 does not have a movable part, and the fixed side locking rod 2-1A does not swing (rotate) and maintains a vertical position. In other words, the fixed side locking rod 2-1A does not change its position relative to the beam holding part 1, and its position relative to the beam holding part 1 is fixed.

[0032] The movable part 4-1 will be described with reference to FIG. The movable part 4-1 has a first member 4-1A fixed to the beam holding part 1, and a second member 4-1B rotatably connected to the first member 4-1A and fixed to the rotation-side locking rod 2-1B. A spring EL is connected to the second member 4-1B via a pin 4-1P. The end of the spring EL opposite to the end connected to the second member 4-1B is connected to the beam holding part 1 to which the first member 4-1A is not fixed (the beam holding part 1 on the left in Figure 16). An elastic contraction force indicated by arrow PC acts on the spring EL. When the second member 4-1A rotates relative to the first member 4-1A, the pivot-side locking rod 2-1B, which is fixed to the second member 4-1A, also rotates. As shown in FIG. 16, when the pivot-side locking rod 2-1B is in the open position, the spring EL exerts an elastic contraction force in the direction of arrow PC, which acts to rotate (close) the pivot-side locking rod 2-1B in the direction of arrow C. On the other hand, when the pivot-side locking rod 2-1B is in the closed position shown in FIG. 18, the pivot-side locking rod 2-1B rotates (opens) in the direction of arrow CC, resulting in the open state shown in FIG. 16. The elastic contraction force of the spring EL in the direction of arrow PC is sufficient to secure the pivot-side locking rod 2-1B, but is not strong enough to prevent a user from placing the pivot-side locking rod 2-1B in the open state shown in FIG. 16.

[0033] In Figures 16 to 18, the fixed side locking rod 2-1A and the rotating side locking rod 2-1B are bent at their upper ends to form a roughly L-shaped overall structure, similar to the bracket locking rod 2 in the first embodiment, and the bent parts at the upper ends (the parts corresponding to the short lines of the L) form locking pieces 3-1A and 3-1B. In the second embodiment as well, the locking pieces 3-1A and 3-1B can be placed on the locking portions 12A of the bracket 12 (FIGS. 19 to 22). 16, the locking piece 3-1B on the rotating side locking rod 2-1B side is not placed on (locked with) the locking portion 12A (see FIGS. 19, 20, etc.) of the bracket 12. On the other hand, when the rotating side locking rod 2-1B is in the state shown in FIG. 18, the locking piece 3-1B on the rotating side locking rod 2-1B side (and the locking piece 3-1A on the fixed side locking rod 2-1A side) can be placed on (locked with) the locking portion 12A of the bracket 12. Other configurations, actions, and effects of the guardrail beam attachment / detachment assist jig 10-1 of the second embodiment are the same as those of the first embodiment shown in Figures 1 to 15. And, like the first embodiment, the second embodiment can be applied to the guardrails shown in Figures 7 and 8.

[0034] 19 and 20, the work of attaching a guardrail beam 11 (see Figures 21 and 22; not shown in Figures 19 and 20) to a bracket 12 using a guardrail beam attachment / detachment assist jig 10-1 according to the second embodiment will be described. As shown in FIG. 19, the guardrail beam attachment / detachment assist jig 10-1 is moved in the direction of arrow B from below the bracket 12 and placed near the bracket 12. At this time, the rotating-side locking rod 2-1B is rotated in the direction opposite to the arrow C in Figure 19 to the state (open state) shown in Figure 16, thereby increasing the distance between the locking piece 3-1B of the rotating-side locking rod 2-1B and the locking piece 3-1A of the fixed-side locking rod 2-1A. By increasing the distance between the locking pieces 3-1A and 3-1B, the locking pieces 3-1A and 3-1B do not interfere with the locking portion 12A of the bracket 12 and do not damage the bracket 12. As shown in Figure 19, the locking piece 3-1A of the fixed-side locking rod 2-1A rests on the locking portion 12A of the bracket 12, thereby locking the locking piece 3-1A to the locking portion 12A. In the state shown in Figure 19, the locking piece 3-1B of the rotating-side locking rod 2-1B is not resting on (locked to) the locking portion 12A of the bracket 12.

[0035] From a state in which the locking piece 3-1A of the fixed-side locking rod 2-1A is locked to the locking portion 12A of the bracket 12 (the state shown in FIG. 19), the rotating-side locking rod 2-1B is rotated in the direction of arrow C in FIG. 19. At that time, the elastic contraction force of the spring EL acts, encouraging the rotation of the rotating-side locking rod 2-1B in the direction of arrow C. When the rotating-side locking rod 2-1B is rotated in the direction of arrow C, the locking piece 3-1B of the rotating-side locking rod 2-1B is placed on the locking portion 12A of the bracket 12, and the locking piece 3-1B is locked to the locking portion 12A. In other words, the rotating-side locking rod 2-1B is rotated in the direction of arrow C in Fig. 19 to the state (closed state) shown in Fig. 18, thereby reducing the gap between the locking piece 3-1B of the rotating-side locking rod 2-1B and the locking piece 3-1A of the fixed-side locking rod 2-1A. By closing the rotating-side locking rod 2-1B, the locking piece 3-1B of the rotating-side locking rod 2-1B is also placed (locked) on the locking portion 12A of the bracket 12, as shown in Fig. 20. In Figure 20, when a guardrail beam 11 (see Figures 14, 15, 21, and 22; not shown in Figure 20) is placed in the beam holding portion 1 of the guardrail beam attachment / detachment assist jig 10-1, the weight of the guardrail beam 11 is securely supported by the bracket 12 via the beam holding portion 1, the locking pieces 3-1A and 3-1B, the locking portion 12A of the bracket 12, and the beam mounting bolt 14 (Figure 7). Therefore, in the second embodiment as well, the guardrail beam 11 can be accommodated in the beam holding portion 1 of the guardrail beam attachment / detachment assist jig 10-1, which is engaged with the bracket 12, without using a large number of workers, and the guardrail beam 11 can be maintained in a state where it is positioned adjacent to the bracket 12. Then, the bolt through-holes 12B (FIG. 20) of the bracket 12 are aligned with the bolt through-holes (not shown) of the guardrail beam 11, and the beam mounting bolts 14 (FIG. 7) are inserted and fastened, whereby the guardrail beam 11 is attached to the bracket 12.

[0036] In the illustrated second embodiment, Open the locking piece 3-1B of the pivoting side locking rod 2-1B (as shown in Figure 16), and move the guardrail beam attachment / detachment assist jig 10-1 upward (in the direction of arrow B in Figure 19) from below the bracket 12. The locking piece 3-1A of the fixed side locking rod 2-1A is locked to the locking portion 12A of the bracket 12, The rotation side locking rod 2-1B is closed (to the state shown in FIG. 18), and the locking piece 3-1B of the rotation side locking rod 2-1B is placed (locked) on the locking portion 12A of the bracket 12. By this simple operation, the weight of the guardrail beam 11 can be reliably supported by the bracket 12. 20, the locking pieces 3-1A and 3-1B of the left and right bracket locking rods 2-1A and 2-1B are placed on the pair of left and right locking portions 12A of the bracket 12 shown in FIG. 20, and the locking pieces 3-1A and 3-1B are locked to the locking portions 12A of the bracket 12, thereby locking at two points. Therefore, compared to the prior art (Patent Document 1) in which the jig is locked to the support post at only one point, the guardrail beam attachment / detachment assist jig 10-1 is much less likely to come off the bracket 12, and the possibility of the guardrail beam attachment / detachment assist jig 10-1 coming off the bracket 12 at a timing that the worker does not expect is greatly reduced, thereby improving the safety of the worker when installing the guardrail beam 11.

[0037] With reference to Figs. 21 and 22, the operation of removing the guardrail beam 11 from the bracket 12 using the guardrail beam attachment / detachment assisting jig 10-1 according to the second embodiment will be described. 21, the guardrail beam 11 is housed in the beam holding section 1, and the guardrail beam attachment / detachment assist jig 10-1 is moved in the direction of arrow B from the space behind the guardrail beam 11 (the side perpendicular to the paper surface and away from the viewer in FIGS. 14 and 15). Then, the pivoting-side locking rod 2-1B and the fixed-side locking rod 2-1A are inserted into the space behind the guardrail beam 11, and the fixed-side locking rod 2-1A is locked to the locking section 12A of the bracket 12. Here, the pivoting-side locking rod 2-0 is in an open state (the state shown in Figure 16), and the gap between the locking piece 3-1B of the pivoting-side locking rod 2-1B and the locking piece 3-1A of the fixed-side locking rod 2-1A is large, so the locking pieces 3-1B and 3-1A do not interfere with the locking portion 12A of the bracket 12. Furthermore, even if the guardrail beam attachment / detachment assist jig 10-1 is moved in the direction of arrow B, the guardrail beam 11 will not be damaged, and the pivoting-side locking rod 2-1B and the fixed-side locking rod 2-1A can be inserted very easily into the space behind the guardrail beam 11. In the state shown in Figure 21, the rotating side locking rod 2-1B is in an open state (as shown in Figure 16), and its locking piece 3-1B is not placed on the locking portion 12A of the bracket 12, so the locking piece 3-1B and the locking portion 12A are not locked together.

[0038] 21, the pivoting-side locking rod 2-1B is closed (rotated in the direction of arrow C in FIG. 19), and the locking piece 3-1B of the pivoting-side locking rod 2-1B is placed on the locking portion 12A of the bracket 12, and the locking piece 3-1B is locked to the locking portion 12A. That is, the pivoting-side locking rod 2-1A is rotated (rotated in the direction of arrow C in FIG. 19) to the closed state shown in FIG. 18, and the locking piece 3-1B of the pivoting-side locking rod 2-1B is placed on (locked with) the locking portion 12A of the bracket 12 (FIG. 22). As shown in Figure 22, both the locking piece 3-1B of the rotating side locking rod 2-1B and the locking piece 3-1A of the fixed side locking rod 2-1A are locked to the locking portion 12A of the bracket 12 at two points (left and right in Figure 22), so the weight of the guardrail beam 11 is securely supported by the bracket 12 via the beam holding portion 1, the locking pieces 3-1A and 3-1B, and the locking portion 12A of the bracket 12, even if the beam mounting bolt 14 (see Figure 7: not shown in Figure 22) is removed.

[0039] 22, even if the beam mounting bolts 14 are removed and the guardrail beam 11 and bracket 12 are released from their fixed state, the weight of the guardrail beam 11, which is a heavy object, is reliably supported by the bracket 12 via the guardrail beam attachment / detachment assist jig 10-1 and the bracket 12. Therefore, the guardrail beam 11 can be maintained in a position adjacent to the bracket 12 without the need for multiple workers to hold and support the guardrail beam 11. As mentioned above, When removing the guardrail beam 11 from the bracket 12, the guardrail beam 11 is stored in the beam holding portion 1, The rotating side locking rod 2-1B and the fixed side locking rod 2-1A are inserted into the space behind the guardrail beam 11, The fixed side locking rod 2-1A is locked to the locking portion 12A of the bracket 12, and the rotating side locking rod 2-1B is swung (rotated) to the closed state shown in FIG. 18, and the locking piece 3-1B is placed on the locking portion 12A of the bracket 12. With this simple operation, the weight of the guardrail beam 11 can be reliably supported by the bracket 12. Furthermore, there is an extremely small possibility that the guardrail beam attachment / detachment assist jig 10-1 will come off the bracket 12 at a timing that the worker does not anticipate, improving the safety of the worker when removing the guardrail beam 11.

[0040] Next, a third embodiment of the present invention will be described with reference to Figures 23 to 38. In Figures 23 to 38, the same components as those in the first and second embodiments are denoted by the same reference numerals. 23 to 29, a guardrail beam attachment / detachment assisting jig 10-2 according to the third embodiment has a beam holding portion 1, a bracket locking rod 2-2, and a back portion BA. 23 to 26, the beam holding unit 1 has a pair of front rods 1-1 extending vertically in FIGS. 24 and 26 on the front side (the viewer's side in FIG. 24: the side indicated by arrow F in FIGS. 23, 25, and 26), a pair of bottom rods 1-2 connected to the lower ends of the front rods 1-1 and extending toward the rear BA side (the side opposite the viewer in FIG. 24: the side indicated by arrow B in FIGS. 23, 25, and 26), a first beam-like member 1H connecting the upper ends of the pair of front rods 1-1, a rear rod 1-3 connected to the end of the bottom rod 1-2 on the rear BA side and extending diagonally upward, and a second beam-like member 3-1 connecting the two rear rods 1-3 and extending horizontally. The beam holding unit 1 also has a storage section R, and when the guardrail beam is attached or detached, the space within the storage section R stores the guardrail beam 11 (not shown in FIGS. 23 to 29; see FIGS. 35 to 38). The bracket locking rod 2-2 has a bracket locking portion 2-2H extending horizontally. As shown in Figures 23, 24, and 26, the bracket locking rod 2-2 is provided on only one side, either the left or right. In Figures 23 to 26, the left end of the bracket locking portion 2-2H (the opposite side to the bracket locking rod 2-2) has an end 2-2HE that protrudes vertically.

[0041] The back portion BA is a collective term for the members of the back portion (the side opposite the viewer in FIG. 24: the side of arrow B in FIGS. 23, 25, and 26) of the guardrail beam attachment / detachment assist jig 10-2. In FIGS. 23 to 26, the back portion BA includes a first rearward extension member 3-21 connected to the upper end of the bracket locking rod 2-2 and extending toward the back portion BA, a second rearward extension member 3-22 extending obliquely upward from one end of the second beam member 3-1, a third beam member 3-31 connected to the end of the second rearward extension member 3-22 and extending parallel to the first and second beam members 1H, 3-1, a fourth beam member 3-32 connected to the end of the first rearward extension member 3-21 and extending parallel to the first and second beam members 1H, 3-1, and a fourth beam member 3-33 connected to the end of the first rearward extension member 3-21 and extending parallel to the first and second beam members 1H, 3-1. The fourth beam member 3-32 has a first vertical member 3-33 extending vertically in a region closer to the center than the ends of the fourth beam member 3-31 and 3-32, a second vertical member 3-34 extending parallel to the first vertical member 3-33 and connecting to the ends of the first and second rearward extending members 3-21 and 3-22, a first rearward extending member 3-21 extending obliquely from one end of the bracket engaging portion 2-2H toward the back portion BA, and a disengagement prevention rod 3-4 rotatably connected to an end 3-32E of the fourth beam member 3-32 opposite the first rearward extending member 3-21 side. The end 3-4E of the disengagement prevention rod 3-4 protrudes in a direction substantially perpendicular to the longitudinal direction of the rod 3-4. The fourth beam member 3-32 is connected to the vertical members 3-33 and 3-34 and the first rear extension member 3-21, and extends parallel to the third beam member 3-31. The first rearward extending member 3-21 extends from the upper end of the bracket locking rod 2-2 toward the back portion BA, that is, in a direction substantially perpendicular to the direction in which the bracket locking portion 2-2H extends. The vertical member 3-33 is positioned to the right (toward the first rear extension member 3-21 (see FIG. 25)) of the longitudinal center of the third and fourth beam members 3-31 and 3-32 in FIG. 24. This is to prevent interference between the bracket mounting bolt 15 (see FIG. 7, etc.) and the nut that screws into it. Here, the first and second rearward extension members 3-21, 3-22 are provided only at one end of the bracket locking portion 2-2H, and are not provided on the side where the disengagement prevention rod 3-4 is provided (the left side in FIGS. 24 and 27). The first and second rearward extension members 3-21, 3-22 are not provided in the area to the left of the first to fourth beam members 1H, 3-1, 3-3, 3-32 in FIGS. 23 and 24, and this area (the area where the first and second rearward extension members 3-21, 3-22 are not provided) forms an opening 3S. In other words, the opening 3S is provided on the side where the disengagement prevention rod 3-4 is provided (the left side in FIGS. 24 and 27).

[0042] In Figures 23, 25 and 26, reference numeral 3-4G denotes a knob for gripping the removal prevention rod 3-4 with the fingers of an operator. In order to simplify the illustration, the removal prevention rod 3-4 is omitted from Fig. 24. Similarly, in order to simplify the illustration, the first rearward extension member 3-21 is omitted from Fig. 26. 23 and 26, the directions in which the removal prevention rod 3-4 rotates relative to the end 3-32E of the fourth beam member 3-32 are indicated by arrows R23 and R26, respectively. In FIGS. 23 to 26, when the removal prevention rod 3-4 rotates as indicated by arrow R23 (FIG. 23) or arrow R26 (FIG. 26) and the end 3-4E of the removal prevention rod 3-4 engages (closes) with the bracket locking portion 2-2H, the state shown in FIGS. 27 to 29 is reached. In this state (when the removal prevention rod 3-4 is closed), the end 3-4E of the removal prevention rod 3-4 is located closer to the bracket locking rod 2-2 (to the right in FIG. 27) than the end 2-2HE that protrudes upward from the bracket locking portion 2-2H, thereby preventing the removal prevention rod 3-4 from coming off the bracket locking portion 2-2H.

[0043] The removal prevention rod 3-4, which is not shown in Fig. 24, is shown in Fig. 27 with its end 3-4E engaged with the bracket locking portion 2-2H. The first rear extension member 3-21, which is not shown in Fig. 26, is also shown in Fig. 29. As will be described later with reference to Figures 30 to 38, when the guardrail beam attachment / detachment assist jig 10-2 is placed on top of the bracket 12 to attach or detach the guardrail beam 11 to or from the bracket 12, the end 3-4E of the detachment prevention rod 3-4 does not engage with the bracket locking portion 2-2H, as shown in Figures 23 to 26, and is positioned on the back BA side (the side opposite the viewer in Figure 24: the side indicated by arrow B in Figures 23, 25, and 2) (open state). On the other hand, when the guardrail beam 11 is stored in the storage portion R, the end 3-4E of the detachment prevention rod 3-4 engages with the bracket locking portion 2-2H (closed state), as shown in Figures 27 to 29.

[0044] 30 to 38, a description will be given of how to attach or detach the guardrail beam 11 to or from the bracket 12. Similar to the first and second embodiments, the third embodiment can also be applied to the guardrails shown in FIGS. 30 to 36, a method for attaching the guardrail beam 11 to the bracket 12 will be described. 30, first, the guardrail beam attachment / detachment assist jig 10-2 is moved in the direction of arrow R30 from the right side of the bracket 12 (from the direction of arrow R30) and advanced into the bracket 12 from the side where the opening S (FIGS. 24 and 27) is provided (the jig 10-2 is inserted). Then, the bracket locking portion 2-2H of the bracket locking rod 2 is placed on the upper end surface of the locking portion 12A of the bracket 12. When the bracket locking portion 2-2H is placed on the upper end surface of the locking portion 12A of the bracket 12, the bracket locking portion 2-2H comes into contact with the upper end surface of the locking portion 12A of the bracket 12 as shown in Figure 31, and the weight of the guardrail beam 11 stored in the guardrail beam attachment / detachment assist jig 10-2 and the storage portion R of the beam holding portion 1 is supported by the upper end surface of the locking portion 12A of the bracket 12 via the guardrail beam attachment / detachment assist jig 10-2.

[0045] In Figure 30, when guardrail beam attachment / detachment assist jig 10-2 is moved in the direction of arrow R30, the removal prevention rod 3-4 is in the open state (the state shown in Figures 24 to 26) as shown in Figure 30 to prevent guardrail beam attachment / detachment assist jig 10-2 from interfering with the support post 13. By opening the removal prevention rod 3-4, guardrail beam attachment / detachment assist jig 10-2 can be inserted. As shown in Figure 32, the removal prevention rod 3-4 rotates in the direction of arrow R32. When the removal prevention rod 3-4 is rotated in the direction of arrow R32, the end 3-4E of the removal prevention rod 3-4 engages with the bracket locking portion 2-2H, and the removal prevention rod 3-4 enters a closed state as shown in Figures 27 to 29, 33, and 34.

[0046] The guardrail beam attachment / detachment assisting jig 10-2 is shown in Figures 33 and 34 with the anti-detachment rod 3-4 in a closed state, and the guardrail beam 11 is accommodated in the accommodation portion R in the state shown in Figures 33 and 34. When the guardrail beam 11 is accommodated in the accommodation section R, the rod 3-4 for preventing the guardrail beam from coming off the bracket 12 is prevented from coming off because the rod 3-4 for preventing the guardrail beam from coming off is closed. Then, bracket locking portion 2-2H of guardrail beam attachment / detachment assist jig 10-2 comes into contact with the upper end surface of locking portion 12A of bracket 12, and the weight of guardrail beam 11 housed in guardrail beam attachment / detachment assist jig 10-2 and housing portion R of beam holding portion 1 is reliably supported by locking portion 12A of bracket 12. Therefore, by housing guardrail beam 11 in housing portion R, guardrail beam 11 can be held by guardrail beam attachment / detachment assist jig 10-2 without the need for multiple workers to hold the guardrail beam 11.

[0047] In Figure 35, which shows the guardrail beam 11 supported by the guardrail beam attachment / detachment assist jig 10-2, the bolt through-hole 12B (Figure 12) of the bracket 12 is aligned with the bolt through-hole (not shown) of the guardrail beam 11, and the beam mounting bolt 14 (Figures 7, 36) is inserted and fastened thereto, thereby firmly attaching the guardrail beam 11 to the bracket 12. In the third embodiment, the weight of the guardrail beam 11 can be reliably supported by the bracket 12 through a simple operation of moving the guardrail beam attachment / detachment assist jig 10-2 from the side of the bracket 12 (the right side in Figure 30) in the direction of arrow R30 (Figure 30), placing the bracket locking portion 2-2H on the locking portion 12A of the bracket 12, and rotating the anti-detachment rod 3-4 in the direction of arrow R32 (Figure 32). As described above, if the bracket locking portion 2-2H of the guardrail beam attachment / detachment assist jig 10-2 is placed on the locking portion 12A of the bracket 12, the jig 10-2 is unlikely to come off the bracket 12. Therefore, the guardrail beam attachment / detachment assist jig 10-2 will not come off the bracket 12 at a timing that the worker does not expect, improving the safety of the worker during the installation work of the guardrail beam 11.

[0048] Next, the operation of removing the guardrail beam 11 from the bracket 12 using the guardrail beam attachment / detachment assisting jig 10-2 according to the third embodiment will be described mainly with reference to FIGS. First, with the guardrail beam 11 fixed to the bracket 12 and the guardrail beam 11 housed in the beam holding portion 1 of the guardrail beam attachment / detachment assist jig 10-2, the guardrail beam attachment / detachment assist jig 10-2 is inserted from the side where the opening S (FIGS. 24 and 27) is provided. At this time, as shown in FIG. 37, the guardrail beam attachment / detachment assist jig 10-2 is moved in the direction of arrow R37 from the right side of the bracket 12 (from the direction of arrow R37) with the removal prevention rod 3-4 open. With the removal prevention rod 3-4 open, the guardrail beam attachment / detachment assist jig 10-2 can be inserted. Then, the guardrail beam 11 is accommodated in the beam holding portion 1, and the guardrail beam attachment / detachment assist jig 10-2 is positioned so that the bracket locking portion 2-2H comes into contact with the upper end surface of the bracket 12.

[0049] Next, as shown in Figure 38, the open release prevention rod 3-4 is rotated in the direction of arrow R38 to engage with the bracket locking portion 2-2H (Figure 37) (closing the release prevention rod 3-4). As a result, the state shown in Figures 35 and 36 is reached, and the bracket locking portion 2-2H of the guardrail beam attachment / detachment assist jig 10-2 is in contact with the upper end surface of the locking portion 12A of the bracket 12. Therefore, the weight of the guardrail beam 11 housed in the guardrail beam attachment / detachment assist jig 10-2 and the housing portion R of the beam holding unit 1 is reliably supported by the locking portion 12A of the bracket 12. This means that the guardrail beam 11 is reliably held by the guardrail beam attachment / detachment assist jig 10-2 without the need for multiple workers to support it. By releasing the beam mounting bolts 14 (Figures 7 and 36), the guardrail beam 11 is separated from the bracket 12, but since the guardrail beam 11 is housed in the beam holding portion 1 of the guardrail beam attachment / detachment assist jig 10-2, there is no risk of the guardrail beam 11 falling. Furthermore, since the anti-detachment rod 3-4 is in a closed state, the guardrail beam attachment / detachment assist jig 10-2 is prevented from coming off the bracket 12 at a timing that the worker does not expect.

[0050] In this way, by using the guardrail beam attachment / detachment assisting jig 10-2 of the third embodiment, when removing the guardrail beam 11 from the bracket 12, the guardrail beam attachment / detachment assisting jig 10-2 is moved (the guardrail beam attachment / detachment assisting jig 10-2) from the side of the bracket 12 (from the direction of arrow R37) so that the bracket engaging portion 2-2H is placed on the bracket 12, and the anti-detachment rod 3-4 is rotated in the direction of arrow R38, which is a simple operation that allows the weight of the guardrail beam 11 to be reliably supported by the bracket 12. Other configurations, operations and effects of the guardrail beam attachment / detachment assisting jig 10-2 of the third embodiment are similar to those of the embodiment of FIGS.

[0051] It should be noted that the illustrated embodiments are merely examples and are not intended to limit the technical scope of the present invention. [Explanation of symbols]

[0052] 1. Beam holding part 2, 2-1, 2-2...Bracket locking rod 2-1A···Fixed side locking rod 2-1B Rotating side locking rod 2-2H Bracket locking part 3, 3-1, 3-1A, 3-1B...locking piece 3-4 Rod to prevent disassembly 4, 4-1...Movable parts 10, 10-1, 10-2... Guardrail beam attachment / detachment support jig BA...back 11. Guardrail beam 12 bracket 12A...Locking part 12B Bolt hole 13...post 14. Beam mounting bolt 15 Bracket mounting bolt EL···Spring

Claims

1. A guardrail beam installation and removal assistance jig characterized by having a beam holding portion that accommodates the guardrail beam, a bracket locking rod that locks onto the bracket, and a locking piece provided at the tip of the bracket locking rod.

2. 2. The guardrail beam attachment / detachment assisting jig according to claim 1, wherein two bracket locking rods are provided, and the bracket locking rods are rotatably supported by a movable portion.

3. The beam holding portion has a storage portion provided continuously below the bracket locking rod, and the storage portion forms a space for storing the guardrail beam, and has a beam-shaped member extending horizontally with the beam holding portion and a connecting portion connected to the bracket locking rod at the movable portion, the movable portion is a hollow sleeve-shaped member, and the bracket locking rod is supported in its internal space so as to be rotatable about its central axis; The anti-rotation mechanism is composed of a bent end of the bracket locking rod and a notch formed below the movable part, The locking piece is bent from the upper end of the bracket locking rod, and when the locking piece faces inward of the guardrail beam attachment / detachment assist jig, it can be placed on the locking part of the bracket, and when the locking piece does not face inward of the guardrail beam attachment / detachment assist jig, it cannot be placed on the locking part of the bracket, A stopper is fixed to the beam holding portion, and when the bent end of the bracket locking rod abuts against the stopper, the bracket preventing rod does not move further downward, A guardrail beam installation and removal assist jig as claimed in claim 2, wherein a rotation prevention mechanism for the bracket locking rod is provided at the lower end of the movable part, the rotation prevention mechanism being composed of the bent end of the bracket locking rod and a notch formed below the movable part, and when the bracket locking rod is not prevented from rotating, the bent end is not accommodated in the notch of the movable part, but is prevented from rotating when the bent end of the bracket locking rod is accommodated in the notch.

4. A guardrail beam attachment / detachment assist jig as claimed in claim 1, which is provided with a movable part for rotating the bracket locking rod, and which comprises a fixed side locking rod that is fixed without changing its position relative to the beam holding part, and a rotating side locking rod that is supported by the movable part so that it can swing.

5. the movable portion has a first member fixed to the beam holding portion and a second member rotatably connected to the first member and fixed to the rotation side locking rod, a spring is connected to the second member by a pin, an end of the spring opposite to the end connected to the second member is connected to the beam holding portion to which the first member is not fixed, and an elastic contraction force acts on the spring, The fixed side locking rod and the rotating side locking rod have their upper ends bent into an L shape, and the bent portion at the upper end of each forms the locking piece, and when the rotating side locking rod rotates around the movable part to an open state, the locking piece on the rotating side locking rod side is not placed on the locking portion of the bracket, and when the rotating side locking rod rotates around the movable part to a closed state, the locking piece on the rotating side locking rod side is placed on the locking portion of the bracket. A guardrail beam attachment and removal assist jig as described in claim 4.

6. The guardrail includes a beam holding portion that accommodates the guardrail beam, a bracket locking rod having a bracket locking portion that can be placed on the upper end surface of the bracket, and a detachment prevention rod that is rotatable and can be engaged with the bracket locking portion.

2. The guardrail beam attachment / detachment assisting jig according to claim 1, wherein an opening is provided on the side where the anti-detachment rod is provided.

7. The beam holding section has a pair of front rods extending vertically, a pair of bottom rods connected to the lower ends of the front rods and extending to the rear, a first beam-like member connecting the upper ends of the pair of front rods, a rear rod connected to the rear end of the bottom rods and extending diagonally upward, a second beam-like member connecting the two rear rods and extending horizontally, and a storage section that stores the guardrail beam in its internal space when the guardrail beam is attached or detached, the bracket locking rod has a bracket locking portion extending horizontally, and an end of the bracket locking portion opposite the bracket locking rod protrudes vertically; a first rear extension member connected to an upper end of the bracket locking rod and extending toward the rear portion; a second rear extension member extending from one end of the second beam member; a third beam member connected to an end of the second rear extension member and extending parallel to the first and second beam members; a fourth beam member connected to an end of the first rear extension member and extending parallel to the first and second beam members; a first vertical member extending vertically in an area closer to the center than the ends of the third and fourth beam members; a second vertical member extending parallel to the first vertical member and connecting to the ends of the first and second rear extension members; a first rear extension member extending from one end of the bracket locking portion toward the rear portion; and a detachment prevention rod rotatably connected to the end of the fourth beam member opposite the first rear extension member side, A guardrail beam attachment / detachment assist jig as claimed in claim 6, wherein the end of the anti-detachment rod protrudes in a direction approximately perpendicular to the longitudinal direction of the anti-detachment rod, and the fourth beam member is connected to the first and second vertical members and the first rear extension member, and extends parallel to the third beam member 3-31.

Images