Device and method for advance side protection on a construction scaffold.
The present invention relates to a railing module with the features mentioned in the preamble of claim 1, as well as a method for producing an advance side pro- tection during the construction of a multi-level construction scaffold.
In the step-by-step construction of multi-level construction scaffolds, the problem arises of ensuring the safety of workers during the assembly process and, in par- ticular, minimizing the risk of falling from the construction scaffold.
The regulations applicable in Germany in this regard were tightened in February 2019, and in directive TRBS 2121, it is now required that during the construction of a construction scaffold, a so-called advance side protection must be ensured at all times.
This means that before the topmost scaffold deck can be accessed,
a side protection, i.e., a railing, must be installed on at least one side facing away from the building.
As the top scaffold deck cannot be accessed before that, this side protection necessarily has to be installed from a lower scaffold level that has already been secured.
The published patent application GB 2 425 563 A, discloses a work platform with a railing arrangement that can be pivotally attached to a scaffolding tower using hooks mounted on both sides next to and below the platform.
The hooks are pivotably attached to the lower part of a two-part railing strut, with the lower part being articulatedly connected to an upper part, and connected via a parallelogram
— bar, allowing them to pivot together in parallel alignment with respect to the lower part.
This mechanism enables a space-saving transport configuration in which the upper and lower parts, as well as the hooks, are laid flat against each other.
In the patent document JP 4069976 B2, various configurations of railing modules for producing an advance side protection are presented.
Some of these embodi- ments consist of an upper and lower rail that are connected to the upper parts of two vertical struts at the opposite ends of the rails to form a substantially rectan- gular frame.
A lower part is articulatedly attached to the upper part of each of the vertical struts, which has two fastening means for securing the railing module to a construction scaffold in the form of two fork couplings.
The publication JP 2003-147953 A proposes a railing module for producing an advance side protection for a construction scaffold, consisting of a roughly rec-
tangular frame and struts hinged to the short ends of the frame.
The struts are in turn made up of two parts hinged together, with the lower part equipped with two distance spacer elements oriented perpendicular to the direction of the lower part and parallel to each other, and a safety bracket, for attaching the railing module to vertical posts of the scaffold.
In the utility model document DE 203 03 960 U1, railing modules for producing an advance side protection for a construction scaffold are disclosed.
These mod- ules consist of a rail and vertically connected struts.
In some embodiments, the vertical struts have fastening means that are arranged on a separate support rod connected to the vertical strut via a parallelogram linkage.
In the European patent document EP 0 283 416 B1, a railing module for an ad- vance side protection is presented, comprising an upper and a lower horizontal rail, each end of which is connected to two undivided vertical posts.
Each of the vertical posts has three fastening means for attachment to a vertical post of the scaffold to be secured.
Two of the fastening means are located in a lower area and the third in an upper area of the respective vertical post.
The Japanese patent document JP 4044874 B2 introduces another railing mod- ule for constructing a scaffold side protection.
This module also includes two un- divided vertical posts, each with a fastening means at the upper end and two more in a lower end area.
The present invention aims to provide a device and a method that allow for the easy and straightforward construction of an advance side guard during the as- sembly of a multi-level construction scaffold.
This objective is achieved through a railing module according to one of claims 1 to 10, which is used in accordance with the assembly method of claims 11 to 14. An essential feature of the inventive railing module is that the vertical posts that support the upper rail usable as support are divided into two parts hinged together by ahinge.
This allows the inventive railing module to be placed in a space-saving transport configuration prior to assembly, where the lower part of each of the at least, preferably exactly, two divided vertical posts forms an angle of 90° or more with the respective upper part of the vertical post connected via the hinge.
This effectively reduces the packing dimensions of the inventive railing module during transport.
According to the invention, two or more fastening means are provided per vertical post with the upper part having at least one of them.
Furthermore, significantly, the lower folding part of each divided vertical post is eguipped with at least one of the fastening means for securing to a scaffold ele- ment, such as a vertical post and/or a horizontal profile running horizontally, such as a scaffold deck-supporting horizontal profile, especially a horizontal U-profile of the construction scaffold.
To produce an advance side guard using the inventive railing module, it is pro- posed to hand over the railing module, configured in transport mode with the lower parts of the divided vertical posts folded, to a worker waiting on the upper- most secured scaffold level.
This worker receives the railing module and initially attaches at least one of the fastening means of the folded lower part of a first vertical post to a scaffold element, such as a horizontal profile of the construction scaffold carrying a scaffold deck to be secured with a leading edge guard, and/or a vertical post supporting the horizontal profile.
Subsequently, the hinge of the vertical post, whose lower part is secured to the vertical post, is opened.
This action causes, due to the fixation of the lower part of the first vertical post, therest of the railing module, consisting of the upper rail, upper part of the first vertical post, and at least one more second vertical post preferably attached at the opposite end of the upper rail, to pivot upwards.
This action is continued until the upper rail extends beyond the topmost not yet se- cured scaffold deck and is pivoted into a parallel position.
The length of the upper rail is adjusted to match the width of the scaffold deck, allowing the lower part of the second vertical post to be folded from its transport position into a position where it aligns with or is at least nearly parallel to the upper part of the vertical post, forming their effective extension.
This lower part of the second vertical post is now attached to scaffold elements on the second side opposite the first side of the secured scaffold deck.
The installation of the side protection is thus completed, and the top scaffold deck can now be ac-
cessed.
For the remaining fields of the top scaffold deck, an advance side protection can likewise be created using additional railing modules.
The advantage of the inventive railing module lies, on one hand, in its simple design and, on the other hand, in its straightforward and fast usage for assem-
bling a leading edge guard, a task achievable by a single worker.
This is a signif-
icant advantage over known railing modules with rigid vertical posts: during the attachment of such a railing module, it needs to be held horizontal to secure both opposite ends to suitable scaffold elements.
However, due to the size of typical scaffold decks and the associated weight of the railing module, usually made of steel or at least aluminum profiles, this is only feasible with two or more workers or with the assistance of equipment like a crane or a pulley system.
Advantageous developments of the present invention, which can be implemented individually or in combination unless they obviously exclude each other, shall be briefly presented below.
Preferably, the inventive railing module has stabilizing struts that run between the upper rail and the two end vertical posts and/or between the two vertical posts.
In particular, in some embodiments, there is a diagonal strut for each of the ver- tical posts, which runs at an acute angle to both the vertical post and the upper rail, providing angular support.
There can be two diagonal struts for one or more vertical posts as well.
Alternatively or additionally, there is also a lower rail running parallel to the upper rail, which particularly connects the lower end of the upper part of the vertical posts.
The upper and lower rails can be connected by a central strut that is pref- erably oriented parallel to the vertical posts.
There can be more than one central strut between the upper and lower rails as well.
The vertically divided vertical posts of the inventive railing module are preferably attached to the opposite ends of the upper rail in a way that there is preferably no or only a minimal protrusion of the rod-shaped upper rail beyond the point of attachment to the vertical post.
According to the invention, the divided vertical posts have two or more fastening means for securing to a scaffold element, such as a horizontal profile and/or a vertical post of the construction scaffold.
The fastening means are arranged in such a way that at least one of them is allocated to each the upper and lower parts of each vertical post.
In particular, the upper part of each of the two divided vertical posts has a fas- 5 tening means for securing this part to a vertical post of the safety scaffold, pref- erably in the form of a clamping or coupling mechanism that wraps around the vertical post like a sleeve, pointing away from the vertical post.
A form-fit connec- tion is achieved through a securing pin inserted through two openings in the op- posite ends of the clamping mechanism.
The lower section of each of the divided vertical posts has, in preferred embodi- ments, two fastening means.
One of these can be similar to the upper part's cou- pling or designed as a fork secured with a bolt, and a second fastening means is provided in the form of a hook or fork.
This second fastening means is used to temporarily connect the lower part of the vertical post to a scaffold element, such as a horizontal profile, like a horizontal U-profile of the scaffold, particularly a horizontal profile of the top, yet unsecured scaffold deck.
The fork coupling on the lower part of each vertical post is preferably located below the hook, so it engages the vertical post of the scaffold in an area below the horizontal profile of the top, yet unsecured scaffold deck.
The inventive railing module preferably exhibits mirror symmetry with respect to a plane defined by the center of the upper rail and its direction.
In preferred embodiments, the railing module of the present invention has a frame consisting of the upper rail, a lower rail running parallel to it at a certain distance, and the two upper parts of the two divided vertical posts.
According to the invention, the lower part of the divided vertical posts is releasa- bly secured in the folded transport position to a lower rail running below the upper rail.
This is done to prevent unintended or uncontrolled unfolding, particularly dur- ing transport to the top secured scaffold level.
The securing means can be an integrated magnet in the lower rail or the vertical post.
For embodiments without a lower rail, the securing is against the upper part of the respective vertical post.
In this case, the hinge must allow the lower part to pivot at least 180 degrees.
As an alternative preferred securing means, a throw retainer can be used, which is pivotally or rotatably mounted in the lower rail or the upper part of the vertical post. It is sized and positioned to pass over the lower end of the pivoted lower part in the second position. To prevent the retainer from unintentionally sliding down, the lower end can have a protrusion on the side facing away from the engagement part, i.e., the lower rail or upper vertical post, which securely en- gages the retainer in the closed position. For this purpose, a protruding end plate that extends over the side surface of the vertical post can also be provided at the lower end of the lower part. In some embodiments, a pre-tensioning element that drives the lower part from the second position towards the first position is present. This can be an integrated spiral spring in the hinge or an elastic element, such as rubber, attached to the side of the engagement part facing the lower part. It ensures that the lower part sits snugly in the latch with slight tension, serving as additional security against unintended opening, especially during transport. In other embodiments, there is no separate pre-tensioning element, and the in- herent bending elasticity of the lower part takes over its function. To relieve the hinge in these embodiments, a support, such as a metal, wood, or rubber ele- ment, can be present between the lower vertical post and the engagement part, attached to the latter. This support serves to cushion the hinged section of the lower part against the support when the lower part is pivoted into the second, i.e., transport position. In preferred embodiments, the upper and lower parts of the divided collapsible vertical posts are detachably connected through the hinge. This allows the railing module to be subsequently removed even when in the assembled state, by dis- connecting the connection between the upper and lower parts, and removing the railing module without the lower parts of the vertical posts. In particularly pre- ferred embodiments, the hinge that connects the upper and lower parts of each of the divided vertical posts is formed from a perforated fork, associated with one of the two parts, and a perforated end piece of the opposing part. The end piece is inserted into the fork, aligning the openings with the holes in the fork, and se- cured with a hinge pin serving as an axis. The hinge pin is secured using a screw nut.
In the inventive method, a device is preferably used, which has a coupling on the upper and lower parts of each of the divided vertical posts and a hanging hook on the lower part, as fastening means.
When using such a device, in preferred embodiments of the method, it is recommended that in the second step, the lower part is first hooked into a horizontal profile of the top, yet unsecured, scaffold deck, and only after that is the coupling of the lower part secured to a vertical post.
Then the hinge of the just secured vertical post is unfolded around the railing module, particularly moving the upper rail beyond the top scaffold deck.
To secure the second divided vertical post to the end of the upper rail opposite the first one, their hinge is unfolded so that the lower part becomes parallel to or extends the upper part.
However, to facilitate hanging the hanging hook, it is rec- ommended to not fully unfold the hinge but leave a small angle of about 5-10 degrees between the upper and lower parts.
Then the hanging hook is hung, and only after that is the lower part of the second vertical post folded into its final position in extension of the upper part.
After securing the fastening means of the second divided vertical post attached to the opposite end of the upper rail to the corresponding horizontal profile or vertical posts of the scaffold, it is suggested to extend the vertical posts over the top scaffold deck if not done already, and then fasten the fastening means of the upper part to these extended vertical posts on both ends of the scaffold deck.
This completes the full securing of the inventive railing module.
However, even before this extension of the vertical posts and fastening means, there is already sufficient protection against falling from the top scaffold deck in the area of this scaffold deck, allowing a worker to step onto it and perform work while being secured.
As the inventive railing module uses fastening means to secure the lower part against an engagement part, such as a lower rail or the upper part of the same vertical post, this must be released at an appropriate time during assembly.
For the first post hung on the scaffold, this can be done before or after hanging the first fastening means of the lower part of the first vertical post.
The latter has the advantage that the fastening means provides additional support to the lower part, making precise hanging easier.
However, releasing the fastening means might be more difficult since the lower part of the vertical post is no longer freely mov-
able.
The former case has correspondingly reversed pros and cons.
If the fastening means is a throw retainer rotatably mounted in the engagement part, stripping it off the lower end of the lower part requires pivoting it towards the engagement part by a few degrees.
This is even more relevant when a protrusion on the side facing away from the engagement part secures the latch from unin-
tentionally sliding down the lower end.
Further features, characteristics, and advantages of the present invention will be- come apparent from the preferred embodiments presented below with reference to the figures.
These are intended to illustrate the subject of the invention only and not restrict its generality in any way.
Shown are in:
Figure 1: A top view of a first preferred embodiment of the railing module accord- ing to the present invention.
Figure 2: A schematic, non-scale top view of a non-claimed embodiment of a railing module.
Figures 3A - F: An illustration of the inventive process for producing a leading edge protection using the inventive railing module according to the first embodi- ment from Figure 1.
Figures 4A-D: A preferred embodiment of the inventive railing module with a transport securing and its use.
In Figure 1, a first embodiment of the inventive railing module is shown in a top
— view.
The railing module 1 consists of a frame 2 formed from the upper rail 3 in the shape of a metallic hollow profile with a sguare cross-section and a similar lower rail 6 spaced apart and parallel to the upper rail 3. The upper rail 3 and the lower rail 6 are connected by a central, specifically, in a mirror symmetry plane of the railing module 1, positioned middle strut 7. Furthermore, an upper part 40 of a two-part vertical rod 4 is respectively connected to the upper rail 3 and the lower rail 6 at the opposite ends.
The upper parts 40 of the vertical rods 4 and the middle strut 7 are parallel to each other and perpendicular to the upper rail 3 and the lower rail 6.
The upper parts 40 and lower parts 4u of the vertical rods 4 are pivotably con- nected to each other via respective hinges 41. The hinge 41 is formed by a fork 4v1 of the lower part and a protruding end 401 of the upper part, which is gripped by the fork 4v1. A bolt 411, specifically a hexagonal bolt, serves as the hinge axis and is secured by a nut (not visible) and passes through two aligned openings in the fork 4v1 of the lower part 4u and the end 401 of the upper part.
This creates a detachable connection between the upper part 40 and lower part 4u, allowing the railing module to be retrofitted in the inserted state.
The lower parts 4u of the vertical rods 4, which are shown in Figure 1 in the transport position where they are folded next to the lower rail 6 of the railing mod- ule and secured against it, have two fasteners 5 in the form of an angled hanging fork 53, a fork-like, outward-facing coupling 51, and a locking pin 52. At the upper parts 40 of the vertical rods 4, a fastener in the form of a cuff-like coupling 54 is also attached, facing outward, i.e., away from the middle strut 7. The fork cou-
plings 51 of the lower parts 4u of the vertical rods 4 are attached to the lower end of the vertical rods 4, while the hanging hooks 53 of the lower parts 5u of the vertical rods 4 are attached in a central area of the lower parts 4u and extend out of the plane formed by the frame 2.
In Figure 2, a non-claimed embodiment of a railing module is schematically de- picted.
The railing module 1 here again includes a rod-shaped, straight upper rail 3, which is connected at its opposite ends to two vertically divided vertical rods 4 running parallel to each other.
To enhance the mechanical strength of the con-
nection, diagonal struts 6' are present, which are set at a 45° angle both on the vertical rod 4 and the upper rail.
The two vertical rods 4 are each divided into an upper part 40 and a lower part 4u, which are pivotally connected to each other via a hinge 41 in such a way that the lower part, from a transport position where it lies parallel to the upper part, as shown for the right vertical rod of the railing module, can be pivoted to a position where it aligns with the upper part 40 and forms its extension, as indicated by the dashed lines for both vertical rods 4 of the railing module 1.
The second embodiment has the advantage over the first of being even more space-saving when stored and also having a lower weight, making it easier to be moved by hand. Figures 3A to 3F illustrate the inventive assembly process. They each show a scaffold 100 with three adjacent, interconnected scaffold bays and two levels, of which an uppermost one is formed by a scaffold deck 102, and at least in Figures 3A to 3E, there is no reliable protection, i.e., no side protection. The uppermost secured level is the scaffold level 103 in these figures. In Figure 3A, an inventive railing module according to the first embodiment from Figure 1 is shown attached to the left vertical post 101a of the middle scaffold bay. The attachment is carried out by means of the holding fork 51a of the left or, in the shown orientation of the railing module 1, the upper vertical rod 4a of the railing module 1, which grips the vertical post 101a and is secured by the bolt
52a. Furthermore, the hanging hook 53a is hung in a horizontal profile (not visible, concealed by the left scaffold deck 102) carrying the scaffold deck 102, which is also held on the vertical post 101a and the parallel vertical post behind it. In Figure 3B, it is shown how the rest of the railing module 1 is pivoted relative to the now fixed part 4 on the vertical post 101a using the hinge 41a of the left vertical rod 4a, causing the upper rail 3 to be lifted above the scaffold deck 102. The movement carried out by the upper rail is indicated by a curved arrow. In Figure 3C, the railing module 1 has already reached its final position, and now the lower part 4u of the right vertical rod 4b is pivoted from its transport position, in which it lies against the lower rail 6 of the railing module and is detachably secured against it, into a position where it nearly aligns with the upper part 40 of the right vertical rod 4b and forms its extension. This position is reached in Figure 3D. The depicted step concerns the hanging of the right hanging hook 53b of the right vertical rod 4b into the horizontal profile carrying the right end of the middle scaffold deck 102. Hardly visible in the figure, a slight angle of about 2-4 degrees is initially maintained between the upper part and lower part 4u of the right vertical rod 4b to facilitate hanging the hanging hook 53b of the right vertical rod 4b. At the same time, when pivoting the lower part 4u of the right vertical rod 4b, the vertical post 101b of the right side of the scaffold deck is gripped by the fork coupling 51b.
In Figure 3E, the final attachment of the right side of the railing module 1 is shown.
The right hanging hook 53b is now securely hung in the right horizontal profile,
and the fork 51b is secured by locking bolt 52b.
Figure 3F shows how an extension of the vertical posts, including vertical posts
101a and 101b, has been made on the scaffold level with a guardrail, formed by the scaffold deck 102. Gerustrahmen 104 (scaffold frames) are attached to the front vertical posts extending the vertical posts 101b and 101a.
The cuff couplings 54a and 54b of the upper parts 40 of the vertical rods 4a and 4b are secured to these scaffold frames 104.
The inventive railing module thus enables an easily installable leading edge pro- tection, which can be installed by only a single worker on the uppermost secured level 103. Only for transport to the uppermost secured level 103, does this require the support of additional workers or technical aids such as a crane.
Figure 4 illustrates in four subfigures A - D the opening of the transport securing of another preferred embodiment of the inventive railing module.
The railing module 1, which essentially corresponds to the one shown in Figure 1, features safety devices in the form of slip-on retainers 7. These retainers se-
cure the foldable lower part 4u of the vertical rods 4 during the transport of the railing module 1 to the installation site against a contact element, here the lower rail 6 of the railing module.
As seen in Subfigure A, the slip-on retainer 7 is slipped over the lower end 4u1 of the vertical rod.
Through the closing end plate 4u2 of the lower end 4u1, which protrudes on the side facing away from the rail 6, and in cooperation with the bending elasticity of the lower part 4u, which in the second position presses against a support 8 fixed to the lower rail 6 and creates a pre- tension that pushes the lower part away from the rail 6, the slip-on retainer 7 is secured against unintentional slipping due to vibrations of the lower part 4u that may occur during transport.
To release the safety, the lower part 4u must first be pivoted a few degrees toward the lower rail, as indicated by the arrow in Subfigure A, resulting in the position shown in Subfigure B.
Then, as shown in Subfigure C, the slip-on retainer 7 can be pivoted in the direction of the arrow there and slipped off over the closing end plate 4u2 and the lower end 4u1. Only after this can the lower part 4u be folded away from the lower rail 6, which serves as the contact element.
A similar safety mechanism can also be combined with all other embodiments of the inventive railing module, such as the one shown in Figure 2.
List of Reference Characters 1 Scaffold Module 2 Frame 3 Upper Rail 4 Vertical Rod 4a Left Vertical Rod 4b Right Vertical Rod 40 Upper Part of 4, 4a, or 4b 401 Lower End of 40 4u Lower Part of 4, 4a, or 4b 4u1 Lower End of 4u 4u2 End Plate 4v1 Fork at the Upper End of 4u 4 Hinge between 40 and 4u 411 Hinge Bolt 5 Fastening Device 51,51a,b — Fork Coupling 52 Locking Bolt 53 Hanging Hook 54, 54a,b Cuff Coupling 6 Lower Rail 6 Diagonal Strut 7 Slip-on retainer 8 Support 100 Scaffold 101 Vertical Post 101a Left/First Vertical Post 101b Right/Second Vertical Post 102 Uppermost Scaffold Deck 103 Uppermost Secured Level 104 Vertical Frame