Scaffolding safety apparatus and method of installation
A safety apparatus capable of installation around the top level of a scaffolding from one scaffolding level below includes a plurality of support posts and rails. The support posts each have a set of hooks for pivotably attaching rails, and are each capable of attachment to a scaffolding by workers at a lower level so that a portion of the support post extends above the scaffolding's top level work surface. Apparatus installation entails pivotably attaching rails to a first support post, which is raised to the edge of the scaffolding and attached. A second support post is then pivotably attached to the free ends of the rails and similarly raised and attached to form a barrier along one edge of the scaffolding. Auxiliary rails may be pivotably attached to an installed support post from the lower level, and the free ends of these auxiliary rails may be pivotably attached to a third support post, which may then be raised and attached to form an adjacent safety barrier. A final barrier may be erected by way of a finishing post, which may be used to attach auxiliary rails to a previously installed support post. An advantage of the apparatus is that no workers are required to be present atop an unsafe top level of a scaffolding while safety barriers are being installed.
[0001] The present invention relates to the field of scaffolding, and more particularly to safety apparatus used in association with scaffolding.
BACKGROUND OF THE INVENTION[0002] When it is necessary to place workers at an elevated work area during construction or maintenance of structures, scaffolding is typically erected. Many types of prefabricated scaffolding exist. Most are made from tubular metal shaped into modular components which may be assembled in various configurations. Typically, end frames comprising two upright legs with at least one connecting horizontal cross member at their upper ends are interconnected by crossbars to form cuboid scaffolding modules. These modules may be stacked or otherwise interconnected in various ways to create a work area of a desired arrangement and height. The elevated work surface portion of the scaffolding is usually created by laying walk boards (e.g. wooden planks) across the horizontal cross members of adjacent end frames.
[0003] The risk of falling from an elevated work surface of a scaffolding is a common safety concern. At the lower levels of a multi-level scaffolding, the risk of falling may be somewhat diminished due to the presence of interconnecting crossbars or other structure between the scaffolding's upright legs which effectively serves as a safety barrier. Nevertheless, gaps in the surrounding support structure at these levels, such as the openings which may exist in so-called “walk-through” or “sidewalk” end frames for example, do leave some risk of falling. At the top level of a scaffolding, safety concerns are usually greatest because of the absence of any surrounding support structure around the uppermost work surface.
[0004] It is of course possible to erect a safety barrier around a scaffolding's uppermost work surface to reduce the risk of falling therefrom. Unfortunately, known techniques require workers to be present on the uppermost work surface in order to erect such a barrier. Disadvantageously, this requirement creates precisely the risky situation that is sought to be avoided, namely, the presence of workers atop an elevated work surface without any surrounding safety barriers.
[0005] What is therefore needed is a scaffolding safety apparatus and a method of erecting same which may be used to create a safety barrier around an elevated work surface without requiring workers to be present on that surface during its erection.
SUMMARY OF THE INVENTION[0006] In accordance with an aspect of the present invention there is provided a safety apparatus for installation at a top level of scaffolding, comprising a support post having: at least one rail connector to which a rail may be connected; and at least one scaffolding connector arranged for connecting the support post to scaffolding below said top level of the scaffolding such that the at least one rail connector is situated above the top level of the scaffolding.
[0007] In accordance with another aspect of the present invention there is provided a safety apparatus for installation at a top level of scaffolding, comprising a support post having: rail connecting mean s for connecting at least one rail; and scaffolding connecting means for connecting the support post to the scaffolding below the top level of the scaffolding such that the rail connecting means is situated above the top level of the scaffolding.
[0008] In accordance with still another aspect of the present invention there is provided a method of erecting safety apparatus at a top level of scaffolding comprising: attaching an end of at least one rail to a first support post; attaching the first support post to the scaffolding from a level below the top level such that the end of the at least one rail extends above the top level of the scaffolding; attaching an opposite end of the at least one rail to a second support post; and attaching the second support post to the scaffolding from the level below the top level such that the at least one rail extends above the top level of the scaffolding.
[0009] In accordance with yet another aspect of the present invention there is provided a protection bar for attachment across gaps in scaffolding support structure, comprising:
[0010] an elongate member; and a scaffolding interconnection bracket depending from each end of the elongate member, each scaffolding interconnection bracket being so arranged as to be attachable to an upright scaffolding member when the protection bar is inclined from the horizontal and so as to be, after being attached to the upright scaffolding member, non-detachable from the upright scaffolding member when the protection bar is oriented horizontally.
[0011] In accordance with still another aspect of the present invention there is provided a telescoping bar for attachment across gaps in scaffolding support structure comprising: a tube; a telescoping rod slidably received within a first end of the tube; biasing means mounted within the tube so as urge the telescoping rod to slide outwardly from the tube; limiting means to limit the outward sliding of the telescoping bar from within the tube; a first scaffolding interconnection bracket affixed to a second end of the tube; and a second scaffolding interconnection bracket affixed to the outer end of the telescoping rod.
[0012] In accordance with yet another aspect of the present invention there is provided a plank moving tool comprising: a lower arm; an upper arm parallel with the lower arm and offset rearwardly with respect to the upper arm; and a handle extending below the lower arm.
[0013] Other aspects and features of the present invention will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS[0014] In the figures which illustrate an example embodiment of this invention:
[0015] FIG. 1 is a perspective view of an exemplary scaffolding safety apparatus attached to a scaffolding, with magnified views A to E showing some of the apparatus features;
[0016] FIG. 2A is a perspective view of a support post component of the safety apparatus of FIG. 1;
[0017] FIG. 2B is a perspective view of a long rail component of the safety apparatus of FIG. 1;
[0018] FIG. 2C is a perspective view of a short rail component of the safety apparatus of FIG. 1;
[0019] FIG. 2D is a perspective view of a finishing post which may be used in conjunction with the safety apparatus of FIG. 1;
[0020] FIG. 3A is a perspective view of a protection bar component of the safety apparatus of FIG. 1;
[0021] FIG. 3B is a partial cross-sectional view of a telescoping bar component of the safety apparatus of FIG. 1;
[0022] FIG. 3C is a perspective view of a sliding long rail component which may be used in conjunction with the safety apparatus of FIG. 1;
[0023] FIG. 4 illustrates an exemplary safety apparatus in front perspective view during an initial installation step;
[0024] FIG. 5 illustrates the exemplary safety apparatus of FIG. 4 in front perspective view during a subsequent installation step;
[0025] FIG. 6 illustrates the exemplary safety apparatus of FIG. 4 in front perspective view during a further installation step;
[0026] 4
[0027] FIG. 7 illustrates an exemplary erected safety apparatus comprising two barriers following the step of FIG. 6;
[0028] FIG. 8 illustrates an exemplary safety apparatus comprising three barriers;
[0029] FIG. 9 illustrates in rear perspective view the exemplary safety apparatus of FIG. 8 after the installation of a fourth and final safety barrier incorporating a finishing post;
[0030] FIG. 9A is a cross-sectional view illustrating the interconnection between the finishing post of FIG. 9 and a support post attached to the scaffolding;
[0031] FIG. 10 illustrates in perspective view a scaffold plank moving tool; and
[0032] FIG. 11 illustrates a method of using the scaffold plank moving tool of FIG. 10 during scaffolding construction.
DETAILED DESCRIPTION[0033] Referencing FIG. 1, a scaffolding safety apparatus indicated generally at 20 is shown attached to a scaffolding 16. A set of magnified views A to E illustrates in greater detail various features of the safety apparatus 20 as well as various points of attachment of the apparatus 20 to the scaffolding 16. The scaffolding 16 to which the apparatus 20 is attached has a bottom level I and a top level II. The bottom level I includes three walk-through (or “sidewalk”) end frames 60, 62 and 64 interconnected by four crossbar pairs 72a, 72b, 72c, and 72d in a conventional arrangement. A first level work surface 74 comprising wooden planks rests on top of the uppermost horizontal cross members 60a, 62a and 64a of end frames 60, 62 and 64 respectively. The top level II similarly includes three walk-through end frames 66, 68 and 70 interconnected by four crossbar pairs 76a, 76b, 76c, and 76d. The bottom ends of the upright legs of end frames 66, 68 and 70 are fitted into the top ends of the upright legs of end frames 60, 62 and 64 (respectively) in a conventional manner. A top level work surface 78 also comprising wooden planks rests on top of the uppermost horizontal cross members 66a, 68a and 70a of end frames 66, 68 and 70 respectively.
[0034] The safety apparatus 20 shown in FIG. 1 includes four support posts 22, 24, 26, and 28, four long rails 34, 36, 38 and 40, and two auxiliary short rails 30 and 32. Support posts 22, 24, 26 and 28 are attached to end frames 66, 68 and 70 at upright end frame legs 66b, 68b, 70b and 70f (respectively). Long rail 34 is supported between an upper pair of hooks 22a and 24b extending from posts 22 and 24 respectively, and long rail 36 is similarly supported between a lower pair of hooks 22c and 24d of the same two posts. The manner of interconnection between an exemplary long rail 34 and a support post hook 22a is illustrated in magnified view D of FIG. 1. The long rails 38 and 40 are supported between hooks 24a, 26b and 24c, 26d of support posts 24 and 26 in like manner. Short rail 30 is supported between an upper pair of hooks 26a and 28b extending from posts 26 and 28 respectively, and short rail 32 is supported between a lower pair of hooks 26c and 28d of posts 26 and 28. In the exemplary embodiment of FIG. 1, hooks 22b and 22d of support post 22 as well as hooks 28a and 28c of support post 28 do not have any rails attached thereto.
[0035] As will be apparent from FIG. 1, the illustrated apparatus 20 forms a safety barrier around two sides of the uppermost work surface 78. It will be appreciated that this is only one possible configuration of the apparatus 20. By attaching additional support post, long rail and/or short rail components to the scaffolding 16, the apparatus 20 may be extended to provide a safety barrier around additional sides of the work surface 78. Alternatively, if it is only necessary to provide a safety barrier at one side of the work surface 78 for example, it is possible to configure the apparatus 20 accordingly through removal of some of the illustrated support posts, long rails and/or short rails. Thus, an advantage of the apparatus 20 is its capacity of being configured to form various safety barrier arrangements.
[0036] Various components which comprise the safety apparatus 20 of FIG. 1, namely, an exemplary support post 80, long rail 82, and short rail 84, are shown in larger perspective view in FIGS. 2A, 2B and 2C respectively. Referring first to FIG. 2A, a support post 80 intended for attachment to a scaffolding end frame for use as a safety rail support is illustrated. Multiple such support posts 80 may be included in an erected safety apparatus 20 (e.g. posts 22, 24, 26 and 28 of FIG. 1). The support post 80 includes an upright member 80g comprising a hollow metal pipe with a square cross-section and an open top end 80q. The upright member 80g has an outer face 80g-1 and an inner face 80g-2. The terms “outer face” and “inner face” refer to the orientation of the support post 80 with respect to a scaffolding to which it is attached (i.e. the side 80g-1 should face outwardly while side 80g-2 should face inwardly).
[0037] An upper pair of inwardly curved opposing hooks 80a and 80b and a lower pair of inwardly curved opposing hooks 80c and 80d are welded to the outer face 80g-1 of upright member 80g so as to encompass the upright member 80g. The hooks 80a, 80b, 80c and 80d may be J-shaped (as shown in FIG. 2A). Each pair of hooks 80a, 80b and 80c, 80d occupies a plane that is substantially orthogonal to the longitudinal axis of the upright member 80g.
[0038] The support post 80 includes a fixed support 80e and a sliding support 80f which serve as points of attachment of the post 80 to a scaffolding end frame. Fixed support 80e comprises a metal bracket 80i having an inverted U-shape attached to a strut 80h which extends from upright member 80g in a direction that is orthogonal to the inner face 80g-2. The bracket 80i is suitably sized and shaped to be fitted over a horizontal scaffolding member for attaching the support post 80 to a scaffolding. A retaining chain 80j is affixed at one of its ends to the exterior of one side of the bracket 80i, and a hook 80k protrudes outwardly from the other side of the bracket 80i. The chain 80j is of sufficient length to be wrapped under a horizontal scaffolding member received by the bracket 80i during apparatus installation and thereafter hooked onto the hook 80k to secure the bracket 80i and attached support post 80 to the scaffolding. The chain 80j may alternatively be any other tether suitable for securing the bracket 80i to a scaffolding member, such as a strap or cord for example, and similarly the hook 80k may alternatively be any tether connector that is suitable for securing the chosen tether.
[0039] The distance “D1” between the bracket 80i and the inner face 80g-2 of upright member 80g is slightly larger than the outer diameter of the upright leg of the support scaffolding end frame. This is so that when the bracket 80i is fitted over a horizontal member of the scaffolding end frame during installation, the upright leg of the scaffolding end frame may be interposed between the bracket 80i and the upright support post member 80g, so that the inner face 80g-2 of support post 80 may be positioned alongside the outer face of the upright leg of the scaffolding end frame.
[0040] Sliding support 80f includes a metal bracket 80m, strut 801, retaining chain 80n and hook 800 arranged analogously to the arrangement of fixed support 80e. However, rather than being attached directly to the support post's upright member 80g like corresponding strut 80h of fixed support 80e, strut 801 of sliding support 80f is attached to a slidable metal sleeve 80p fitted around the upright member 80g. The slidable sleeve 80p allows the entire sliding support 80f to be translated along the length of upright member 80g so as to adjust the distance “D2” between the fixed support 80e and sliding support 80f. The bracket 80m of sliding support 80f may thus be positioned at horizontal scaffolding members located at various distances from the scaffolding member received by the bracket 80i of (upper) fixed support 80e. The support post 80 may thus be attached to the scaffolding members (as shown in magnified view B of FIG. 1) of various types of scaffolding end frames, whose horizontal members may be differently spaced.
[0041] FIG. 2B illustrates a long rail component 82 of the apparatus 20. The long rail 82 comprises a hollow metal pipe with flanged ends 82a and 82b. Multiple such long rails 82 may be included in an erected safety apparatus 20 (e.g. four long rails 34, 36, 38 and 40 are included in the apparatus 20 of FIG. 1). Each flanged end 82a and 82b has an aperture 82c and 82d (respectively) for receiving an upper or lower hook 80a, 80b, 80c or 80d of a support post 80. The length of the rail 82 is such that the rail 82 may be suspended (by way of its apertures 82c and 82d) between two upper hooks 80a and 80b or two lower hooks 80c and 80d of a pair of erected support posts 80 that are adjacent to one another along a longer side of a scaffolding unit (e.g. in the manner that long rail 34 is suspended between upper hooks 22a and 24b in the apparatus 20 of FIG. 1).
[0042] FIG. 2C illustrates an “auxiliary” short rail component 84 of the apparatus 20. Multiple such short rails 84 may be included in an erected safety apparatus 20 (e.g. two short rails 30 and 32 are included in the apparatus 20 of FIG. 1). The short rail 84 comprises a hollow metal pipe with a first and second flanged end 84a and 84b. First flanged end 84a includes an attached slotted plate 84c. The orientation of the attached slotted plate 84c is such that the major axis of the plate's obround slot 84d is at an obtuse angle &thgr;1 of approximately 135 degrees with respect to the longitudinal axis of the short rail 84. Second flanged end 84b includes an attached slotted plate 84e which is coplanar with slotted plate 84c. The orientation of the second slotted plate 84e is such that the major axis of its obround slot 84f is at an acute angle &thgr;2 of approximately 45 degrees with respect to the longitudinal axis of the short rail 84. The slots 84d and 84f are thus substantially parallel with respect to one another. The slots 84d and 84f are suitably sized so that the curved portion of a support post hook 80a, 80b, 80c or 80d may be passed therethrough during apparatus erection, as will be described. The length of the short rail 84 is such that the rail 84 may be suspended (by way of its slots 84d and 84f) between two upper hooks 80a and 80b or two lower hooks 80c and 80d of a pair of erected support posts 80 that are adjacent to one another along a shorter side of a scaffolding unit (e.g. in the manner that short rail 30 is suspended between upper hooks 26a and 28b in the apparatus 20 of FIG. 1).
[0043] A finishing post 86 that may form part of the safety apparatus 20 is illustrated in FIG. 2D. The finishing post 86 is intended for use during erection of a fourth and final safety barrier wall around a four-sided elevated scaffolding work surface, as will be described. The finishing post 86 includes an upright member 86g comprising a hollow metal pipe with a square cross-section. The upright member 86g has an outer face 86g-1 and an inner face 86g-2, with the terms “outer face” and “inner face” again referring to the intended orientation of the post 86 with respect to a scaffolding to which it is indirectly attached (i.e. the side 86g-1 should face outwardly while side 86g2 should face inwardly). A coupling bracket 86c comprising a curved, downwardly extending flat metal bar is welded at one of its ends to the inner face 86g-2 of the finishing post 86 near the top of the upright member 86g. The downwardly pointing free end of coupling bracket 86c is substantially parallel to the upright member 86g and is sized and shaped to be receivable in the open top end 80q (FIG. 2A) of a support post 80 (FIG. 2A). The coupling bracket 86c serves as a point of attachment of the finishing post 86 to an installed support post, as will be described.
[0044] An upper hook 86a and a lower hook 86b, each occupying a plane that is substantially orthogonal to the longitudinal axis of the upright member 86g, are each welded to the inner face 86g-2 of upright member 86g. The hooks 86a and 86b, which are identical in shape, extend laterally from the upright member 86g and bend back on themselves so as not to encompass the upright member 86g. The finishing post 86 further includes a chain 86d for attaching the base of finishing post 86 to a support post 80 that has been installed onto a scaffolding. One end of the chain 86d is affixed to one side of the upright member 86g near its base. A hook 86e is affixed the other side of the upright member 86g. The chain 86d is of sufficient length so as to be capable of being wrapped around a support post 80 and an upright scaffolding leg to which the post 80 is attached and thereafter being hooked onto the hook 80e, in order to secure the base of the finishing post 86 to the scaffolding. The chain 86d may alternatively be any other tether suitable for securing the base of the finishing post 86 to the scaffolding, such as a strap or cord for example, and similarly the hook 80e may alternatively be any tether connector that is suitable for securing the chosen tether.
[0045] Referring back to FIG. 1, it may be observed that the safety apparatus 20 additionally comprises two identical protection bars 48 and 52 installed across the open walk-through portion of end frames 66 and 70 (respectively). These protection bars 48 and 52 are installed to create additional safety barriers at the edge of the scaffolding's raised work surface 74 beyond those barriers that are effectively created by the surrounding scaffolding support structure (e.g. end frames and crossbars).
[0046] An enlarged view of an exemplary protection bar 88 is provided in FIG. 3A. The protection bar 88 comprises a metal rod 88g with a scaffolding interconnection bracket 88a, 88b at either end for attaching the protection bar 88 between the inner braces of a walk-through type scaffolding end frame. The rod 88g may be any type of elongate member, such as a slat or tube for example. The first scaffolding interconnection bracket 88a comprises a U-shaped retaining bracket 88c and an attached L-shaped angle bracket 88d (also referred to as a support bracket 88d). The base 88c-3 of the U-shaped bracket 88c is welded to the end of the rod 88g so that each of the two sides 88c-1 and 88c-2 of the bracket 88c extend away from the rod 88g in a direction that is substantially parallel to the longitudinal axis 88x of bar 88. The L-shaped support bracket 88d is welded to an outer surface of the side 88c-2 of retaining bracket 88c so that the longitudinal leg 88d-1 of the L-shape extends parallel to axis 88x and the short leg 88d-2 extends transversely across the open end of the U-shaped bracket 88c. The second scaffolding interconnection bracket 88b of the protection bar 88 is a mirror image of the first scaffolding interconnection bracket 88a, with a U-shaped bracket 88e and an attached L-shaped bracket 88f projecting from the end of the bar 88 opposite scaffolding interconnection bracket 88a.
[0047] The gap D3 between wall 88c-1 and leg 88d of a bracket assembly 88c, 88d at one end 88a of bar 88 is greater than the diameter of the vertical end frame inner braces (e.g., 60c, 60d of FIG. 1). The bracket assembly at the other end 88b of the bar 88 has the same gap D3. To install bar 88 on, say, end frame 66 (FIG. 1), a bracket assembly 88c, 88d may be placed around vertical brace 66c of the end frame so that the brace is received in gap D3 and short leg 88d-2 of L-bracket 88d rests atop a horizontal member of the end frame (as seen in magnified view C of FIG. 1). Next the bar 88 is moved to position the vertical brace within the U-bracket 88c. The bar 88 is then angled upwardly until the gap D3 at the other end 88b of the bar is registered with vertical brace 66d. Bracket assembly 88e, 88f may then be placed around brace 66d and end 88b of bar 88 lowered until the short leg 88f-2 of L-bracket 88f rests atop a horizontal member of end frame 66 which is aligned with the horizontal member supporting L-bracket 88d. In this position, vertical braces 66c and 66d are received within respective U-brackets 88c, 88e of bar 88 such that the bar 88 cannot be removed from these braces, unless it is again inclined.
[0048] Referring again back to FIG. 1, it may be seen that the safety apparatus 20 further comprises a telescoping safety bar 54 attached between upright legs 66b and 68b of scaffolding end frames 66 and 68 respectively. The purpose of telescoping bar 54 is to provide an easily attachable (and detachable) safety barrier at an edge of a lower level scaffolding work surface.
[0049] FIG. 3B illustrates an exemplary telescoping bar 90 in partial cross-sectional view. Telescoping bar 90 comprises a hollow metal tube 90g with a metal U-shaped bracket 90b attached to one end. The base of the U-shaped scaffolding interconnection bracket 90b is welded to the end of the tube 90g so as to be substantially orthogonal to a longitudinal axis 90x of the bar 90, with each of the two sides 90b-1 and 90b-2 of the bracket 90b extending away from the tube 90g in a direction that is substantially parallel to longitudinal axis 90x. The telescoping bar 90 further comprises a rod 90c telescopically received within the hollow tube 90g at its other end. An annular plug 90d in the end of tube 90g slidably receives the rod 90c and serves to center the rod 90c within the tube 90g. A metal U-shaped scaffolding interconnection bracket 90a identical to the bracket 90b is attached to the outer end of rod 90c in mirror image to the opposing bracket 90b.
[0050] A plunger 90e extends from the inner end of rod 90c within the tube 90g. The plunger 90e comprises a plunging arm 90e-1 and a foot 90e-2. The plunging arm 90e-1 is substantially parallel to the longitudinal axis 90x. The foot 90e-2 forms a right angle with the plunging arm 90e-1. The plunger 90e may be formed from a bar bent at a right angle to form foot 90e-2 for example.
[0051] A retaining pin 90f is fixedly mounted within tube 90g so as to bisect the hollow interior of the tube 90g. The foot 90e-2 abuts pin 90f at the outward telescoping limit of rod 90c, as shown in FIG. 3B. A spring 90h is compressed between the inner side of foot 90e-2 and a second retaining pin 90i, which too is fixedly mounted within the hollow of tube 90g in the same manner as pin 90f, but more proximately to bracket 90b. Compressed spring 90h urges rod 90c to telescope outwardly from the tube 90g toward the telescoping limit defined by foot 90e-2 abutting pin 90f. The spring constant of the spring 90h should be low enough to permit the rod 90c to be slidably compressed into the hollow tube 90g during installation of the telescoping bar 90, yet high enough to support the weight of the telescoping bar 90 when the bar 90 is installed in horizontal position between two vertical scaffolding members (e.g. in the manner that telescoping bar 54 is shown to be installed in FIG. 1).
[0052] FIG. 3C illustrates an exemplary sliding long rail 92 in perspective view. A sliding long rail 92 can be installed between two adjacent support posts 80 in the place of a lower long rail 82 when it is desired to have a vertically slidable lower long rail. Sliding long rail 92 comprises a hollow metal tube 92g with two metal brackets 92a and 92b attached in mirror image at either end. The brackets 92a and 92b have three bends to form a hook shape with a base for mounting. The mounting bases 92a-1 and 92b-1 of the brackets 92a and 92b are welded to the opposite ends of the tube 90g so as to be substantially orthogonal to the longitudinal axis of the tube 92g. The tube 92g should be sufficiently long so that the brackets 92a and 92b may be hooked around the upright members 80g of two adjacent support posts 80 along the long edge of a scaffolding unit.
[0053] The sliding long rail 92 is intended for installation so as to rest on one of each of two lower hooks 80c, 80d of two adjacent support posts 80 in place of a standard long rail 82. The sliding long rail 92 may be installed by a worker during the installation of support posts 89. When it is desired to move a load onto or off of the scaffolding, the sliding rail 92 may be easily slid upwardly as needed and then lowered back to its resting position on opposed lower hooks 80c, 80d.
[0054] Installation of an exemplary safety apparatus 100 comprising some of the aforedescribed components around a scaffolding 102 is illustrated in FIGS. 4 to 9 and FIG. 9A.
[0055] Beginning with FIG. 4, a scaffolding 102 shown in front perspective view comprises a lower level I and a top level II. The lower level I includes two walk-through end frames 104 and 106 interconnected by crossbars in a conventional manner. The bottom level I includes a first level work surface 150 comprising wooden planks resting atop the uppermost horizontal cross members 104a and 106a of end frames 104 and 106 respectively. A top level II of the scaffolding 102 comprises two walk-through end frames 108 and 110 similarly interconnected by crossbars in a conventional manner, with a first pair of crossbars 112a (which interconnects the front upright legs 108b and 110b) being visible and a second pair of crossbars (which interconnects rear upright legs 108f and 110f) being omitted for clarity. As can be seen in FIG. 4, the top level work surface, which will comprise wooden planks laid over the top of the uppermost horizontal cross members 108a and 110a of end frames 108 and 110 respectively, may be initially absent from the scaffolding 102. This is to promote improved visibility of the safety apparatus 100 during its installation around the scaffolding's top level.
[0056] A protection bar 154 is installed between inner braces 110c and 110d of end frame 110 to provide improved safety for workers at scaffolding level II while they erect the safety apparatus 100 around the level above. The method of installation is as described hereinbefore with the result that the short legs of the L-shaped support brackets 154d and 154f come to rest atop horizontal end frame members 110j and 110i, respectively, as shown in FIG. 4.
[0057] A pair of long rails 130 and 132 is next attached to the upper and lower hooks 120b and 120d (respectively) of a support post 120. This is achieved by slipping the apertures in flanged ends 130a and 132a onto the hooks 120b and 120d of support post 120 (respectively). Long rails 130 and 132 and support post 120 may be held by one or more workers standing on the first level work surface 150 during this process, for example.
[0058] After the rails 130 and 132 have been attached, the support post 120 is raised to an upright position, with the unattached ends 130b and 132b of the upper and lower long rails 130 and 132 hanging downwardly as shown in FIG. 4. The support post 120 is then attached to the end frame 110 at upright leg 110b. The fixed support 120e and sliding support 120f of support post 120 serve as the points of attachment of the support post 120 to the end frame 110. More specifically, bracket 120i of fixed support 120e is fitted over horizontal scaffolding member 110g and secured in place by the retaining chain 120j, which is wrapped under the horizontal scaffolding member 110g and secured to the hook (not visible) on the opposite side of bracket 120i. The bracket 120m of sliding support 120f is similarly attached to the horizontal scaffolding member 110h. If necessary, before the sliding support 120f is attached to the end frame 110, its sleeve 120p may be slid along the length of the support post 120 to translate the support 120f along the post 120 in order to position the bracket 120m over end frame horizontal member 110h.
[0059] Upon the attachment of fixed support 120e and sliding support 120f, the weight of the support post 120, as well as the long rails 130 and 132 that are connected thereto, will be supported by the support bracket 120i of fixed support 120e.
[0060] Next, as illustrated in FIG. 5 in solid lines, a second support post 122 is attached to the downwardly hanging free ends 130b and 132b of long rails 130 and 132. The support post 122 is attached using the same technique as was used to attached support post 120 to rails 130 and 132, i.e. the apertures in flanged ends 130b and 132b are slipped onto the hooks 122a and 122c of support post 122. The support post 122 is then raised to an upright position and attached to the end frame 108 at its upright leg 108b, as shown in FIG. 5 in ghost outline. The attachment of the support post 122 to the end frame 108 is performed in like manner to the previous attachment of support post 120 to the end frame 110, i.e. fixed support 122e is attached to horizontal end frame member 110g and sliding support 122f is attached to horizontal end frame member 108h. As can be seen in the ghost outline of FIG. 5, this results in the long rails 130 and 132 being raised to a substantially horizontal installed position, where they can serve as a safety barrier or “wall” along the front edge of the scaffolding 102.
[0061] It will be appreciated that the above described procedure may be modified in order to install a sliding long rail 92 in place of the lower long rail 132. Rather than attaching the flanged end 132a of a lower rail 132 to the lower hook 120d prior to installing support post 120 onto the scaffolding 102 as described, the bracket 92a of a sliding long rail 92 (FIG. 3C) should be hooked around the upright member of support post 120 between its upper hooks 120a, 120b and lower hooks 120c, 120d. The support post 120 is then installed onto the scaffolding as described, with the free ends of the upper long rail 130 and sliding long rail 92 being left hanging downwardly in a manner comparable to FIG. 4. Thereafter, the opposing bracket 92b of the sliding long rail 92 is similarly hooked around the second support post 122 between its upper hooks 122a, 122b and lower hooks 122c, 122d, and the support post 122 is raised and installed.
[0062] Turning now to FIG. 6, a further portion of the safety apparatus 100 comprising a second barrier, adjacent to the first barrier that was just erected, is installed above the end frame 108. As an initial step, a protection bar 156 is installed between inner braces 108c and 108d using the same method of installation as was used to attach protection bar 154 to end frame 110. A pair of short rails 134 and 136 are thereafter joined by their flanged ends 134b and 136b to the hooks 122b and 122d of the overhead support post 122. More specifically, the upper short rail 134 is first held on the exterior side of the end frame 108 with its longitudinal axis in substantially parallel alignment with the plane occupied by the end frame 108. The short rail 134 is then inclined to an approximate 45 degree angle from the horizontal in order to raise the flanged end 134b of the rail 134 to the height of the intended attaching hook 122b. At that point the obround slot in plate 134e of flanged end 134b will be horizontally oriented as a result of the 45 degree angle existing between the slot and the longitudinal axis of the short rail 134. The slot in plate 134e is then passed over the (horizontally oriented) curved portion of upper hook 122b as shown in FIG. 6. The free end of the short rail 134 may be allowed to hang downwardly. The lower short rail 136 (and in particular, slotted plate 136e of rail 136) is then joined to hook 122d in an analogous manner, with the free end of the short rail 136 also being left hanging downwardly thereafter.
[0063] Next, a third support post 124 is attached by its hooks 124a and 124c to the downwardly hanging free ends of short rails 134 and 136. More specifically, the third support post 124 is held so that the curved portion of its upper hook 124a becomes aligned with the obround slot in plate 134c of the flanged end 134a of rail 134, and the slot is then passed over the hook's curved portion in order to join the rail 134 to hook 124a. Flanged end 136a of lower short rail 136 is joined to the lower hook 124c of support post 124 in an analogous manner. The support post 124 may then be raised to an upright position and attached to the end frame 108 at upright leg 108f. The technique for attaching the post 124 to the end frame 108 is the same as was used previously. As a result, the short rails 134 and 136 are raised to a substantially horizontal installed position as shown in FIG. 6 in ghost outline, where they can serve as a safety barrier along the shorter edge of the scaffolding 102 above end frame 108.
[0064] As may be seen in FIG. 6 and with additional reference to magnified view E of FIG. 1, the inclination of each of the obround slots in the flanged ends 134a, 134b and 136a, 136b of short rails 134 and 136 when the rails have been installed is approximately 45 degrees from horizontal. This inclination of the slots prevents the short rails from being able to slip off of their respective hooks 122b, 124a, 122d, and 124c.
[0065] FIG. 7 illustrates a completed safety apparatus 100 following the step illustrated in FIG. 6. The completed apparatus 100 provides safety barriers on two sides of the scaffolding 102.
[0066] A safety apparatus 200 having a third safety barrier along the rear edge of the scaffolding 102 is illustrated in FIG. 8. Erection of the structure shown in FIG. 8 requires the installation procedure to proceed to the point illustrated in FIG. 6. Then, before the support post 124 with short rails joined thereto is raised and attached to the scaffolding 102, the flanged ends 138a and 140a of long rails 138 and 140 are attached to hooks 124b and 124d (respectively), leaving the long rails 138 and 140 hanging downwardly following the installation of support post 124. Subsequently, the opposite flanged ends 138b and 140b of long rails 138 and 140 are attached to the hooks 126a and 126c (respectively) of a fourth support post 126, in the same way as support post 122 was previously attached to long rails 130 and 132. The support post 126 is then raised to an upright position and attached to the end frame 108 at its upright leg 108f as shown in FIG. 8, using the now familiar support post attachment method.
[0067] A safety apparatus 300 having a fourth and final safety barrier above end frame 110 is shown in FIG. 9. FIG. 9 illustrates the scaffolding 102 and the attached safety apparatus 110 in rear perspective view. It will be appreciated that the installed front long rails 130 and 132 are omitted from FIG. 9 for clarity.
[0068] As a first step in raising the fourth safety barrier, a pair of short rails 142 and 144 are first attached by their flanged ends 142b and 144d to the hooks 120a and 120c, respectively, of the first overhead support post 120. This is achieved using the same method as was used for attaching the opposite short rails 134 and 136 to support post 122, i.e. by inclining the rails to an approximate 45 degree angle from the horizontal and by passing the substantially horizontal obround slots in flanged ends 142b and 144b over the curved portion of hooks 120a and 120c respectively.
[0069] Next, a finishing post 128 is attached by its hooks 128a and 128b to the downwardly hanging free ends of short rails 142 and 144. This is done by fitting the obround slots in flanged ends 142a and 144a of short rails 142 and 144 over the hooks 128a and 128b. The finishing post 128 is then raised to an upright position. The finishing post 128 is positioned alongside the exterior of installed support post 126 so that the finishing post's downwardly extending coupling bracket 128c is over the opening 126q in the top of support post 126 and is then lowered until the coupling bracket 128c is received within the opening 126q in support post 126, as shown in FIG. 9A. The weight of the finishing post 128 and the attached short rails 142 and 144 is thus supported by the bracket 128c. The chain 128d at the base of the finishing post 128 is then wrapped around both the support post 80 and the upright scaffolding leg 110f and subsequently hooked onto the hook 128e on the opposite side of the finishing post 128 to ensure that the base of finishing post 128 remains in position alongside the support post 126.
[0070] Advantageously, at this stage the scaffolding 102 has a four-sided safety barrier around its top level, and no workers were required to be present on that top level during its installation.
[0071] To complete the installation, the uppermost work surface of the scaffolding 102 is installed. This installation is facilitated by a plank moving tool 94, illustrated in perspective view in FIG. 10. Plank moving tool 94 comprises a handle 94e with a toothed arm 94a attached at one end. The toothed arm 94a forms a right angle with the handle 94e. A series of teeth 94d for gripping a wooden plank protrude from the side of the toothed arm 94a opposite the handle 94e. The tool 94 further comprises an elbowed clamping arm 94b which is attached at the point of interconnection of the handle 94e with the toothed arm 94a. The upper arm 94b-1 of elbowed clamping arm 94b forms an obtuse angle with the handle 94e. The forearm 94b-3 of the elbowed clamping arm 94b is parallel to the toothed support 94a. A brace 94c extends between the elbow 94b-2 of the clamping arm 94b and the handle 94e, providing structural integrity to the tool 94.
[0072] When the handle 94e of the plank moving tool 94 is pivoted in the direction P, a wooden plank 96 (shown in ghost outline in FIG. 10) may be clamped between the toothed support 94a and the forearm 94b-1 of the elbowed clamping arm 94b. The plank 96 may then be moved or raised into position as necessary. The grip of the tool 94 on the plank 96 is facilitated by the teeth 94d, which may partially embed themselves in the plank 96 as a result of the pivoting movement P.
[0073] To complete the scaffolding 102, a worker standing on the first level work surface 150 (FIG. 8) first raises the plank 96 overhead and situates the plank atop the uppermost horizontal members 108a and 110a of end frames 108 and 110 respectively. The plank moving tool 94 may then be used to grip the plank 96 as shown in FIG. 11 in order to position the plank as needed. This is repeated for each plank comprising the top work surface, in order to complete the scaffolding 102.
[0074] As will be appreciated by those skilled in the art, modifications to the above-described embodiment can be made without departing from the essence of the invention. For example, the support posts 80 could be designed with the hooks being welded to the inner face 80g-2 of the upright member 80g, with the open ends facing outwardly, rather than the arrangement described previously.
[0075] As well, the obround slots 84d, 84f of the auxiliary short rails 84 need not be parallel, nor do they need to be oriented at 45 and 135 degree angles with respect to the rail's longitudinal axis. Rather, it is only necessary that the slot at one end of the rail (namely, the end that is raised for installation) be such that one can make the slot horizontal from below in order to pass the slot over a horizontally oriented hook. The slot at the other end may be at any angle, provided that the slot is not horizontal after installation.
[0076] In a further alternative, all rails (both long and short) may have angled obround slots as described in conjunction with short rails 84, so that it may be possible to install rails to attached support posts from below along any side of a scaffolding.
[0077] Other modifications will be apparent to those skilled in the art and, therefore, the invention is defined in the claims.
Claims
1. A safety apparatus for installation at a top level of scaffolding, comprising:
- (a) a support post having:
- (i) at least one rail connector to which a rail may be connected; and
- (ii) at least one scaffolding connector arranged for connecting said support post to scaffolding below said top level of said scaffolding such that said at least one rail connector is situated above said top level of said scaffolding.
2. The safety apparatus of claim 1, further comprising:
- (b) a rail, including:
- (i) a post connector arranged so as to be freely joined and released by said at least one rail connector when said rail makes a first angle with said post and so as to be, after being joined to said at least one rail connector, unreleasably joined to said at least one rail connector when said rail makes a second angle with said post.
3. The safety apparatus of claim 1, further comprising:
- (b) a finishing post, including:
- (i) at least one finishing post rail connector to which a rail may be connected; and
- (ii) at least one post connector arranged for connecting said finishing post to said support post from below said top level of said scaffolding such that said at least one finishing post rail connector is situated above said top level of said scaffolding.
4. The safety apparatus of claim 1, wherein said at least one scaffolding connector comprises a downwardly opening U-bracket for resting on a horizontal member of said scaffolding.
5. The safety apparatus of claim 4, wherein said at least one scaffolding connector further comprises a depending tether and a tether connector for releasably holding a free end of said tether, said tether and tether connector arranged such that said tether may be wrapped around said horizontal member below said downward opening of said U-bracket and then held by said tether connector.
6. The safety apparatus of claim 1, further comprising a rail having an slot with a major axis making a non-zero angle with a longitudinal axis of said rail.
7. The safety apparatus of claim 6, wherein said slot is a first slot at a first end of said rail with a major axis making a first angle with said longitudinal axis of said rail, and further comprising a second slot at a second end of said rail with a major axis making a second non-zero angle with said longitudinal axis of said rail.
8. The safety apparatus of claim 7, wherein said first angle is approximately 45 degrees.
9. The safety apparatus of claim 8, wherein said major axis of said first slot is substantially parallel to said major axis of said second slot.
10. The safety apparatus of claim 6, wherein said at least one rail connector comprises a hook which lies in a horizontal plane when said support post is upright.
11. The safety apparatus of claim 10, wherein said hook is a J-shaped hook.
12. A safety apparatus for installation at a top level of scaffolding, comprising:
- (a) a support post having:
- (i) rail connecting means for connecting at least one rail; and
- (ii) scaffolding connecting means for connecting said support post to said scaffolding below said top level of said scaffolding such that said rail connecting means is situated above said top level of said scaffolding.
13. The safety apparatus of claim 12, further comprising:
- (b) a rail, including:
- (i) post connecting means arranged so as to be freely joined and released by said rail connecting means when said rail makes a first angle with said post and so as to be, after being joined to said rail connecting means, unreleasably joined to said rail connecting means when said rail makes a second angle with said post.
14. The safety apparatus of claim 12, further comprising:
- (c) a finishing post, including:
- (i) means for connecting at least one rail; and
- (ii) means for connecting said finishing post to said support post from below said top level of said scaffolding such that said at means for connecting at least one rail extend above said top level of said scaffolding.
15. A method of erecting safety apparatus at a top level of scaffolding, comprising:
- (a) attaching an end of at least one rail to a first support post;
- (b) attaching said first support post to said scaffolding from a level below said top level such that said end of said at least one rail extends above said top level of said scaffolding;
- (c) attaching an opposite end of said at least one rail to a second support post; and
- (d) attaching said second support post to said scaffolding from said level below said top level such that said at least one rail extends above said top level of said scaffolding.
16. The method of erecting safety apparatus of claim 15, wherein said at least one rail is as claimed in claim 7, each of said first and second support posts is as claimed in claim 10, and said attaching of step (a) comprises passing said first slot at said first end of said at least one rail over said at least one hook of said first support post, and said attaching of step (c) comprises passing said second slot at said second end of said at least one rail over said at least one hook of said second support post such that during said attaching of step (d), said first and second slots are re-oriented with respect to said hooks of said first and second support posts so as to be unreleasable from said hooks of said first and second support posts.
17. The method of erecting safety apparatus of claim 15, wherein said at least one rail is an at least one first rail and further comprising:
- (a) attaching an end of at least one second rail to said second support post from a level below said top level of said scaffolding;
- (b) attaching an opposite end of said at least one second rail to a third support post; and
- (c) attaching said third support post to said scaffolding from said level below said top level such that said at least one second rail extends above said top level of said scaffolding.
18. The method of erecting safety apparatus of claim 17, further comprising:
- (a) attaching a fourth support post to said scaffolding adjacent to said first attached support post from a level below said top level of said scaffolding;
- (b) attaching an end of at least one third rail to either of said first support post or said fourth support post from a level below said top level of said scaffolding;
- (c) attaching an opposite end of said at least one third rail to a finishing post; and
- (d) attaching said finishing post to the other of said first support post and said fourth support post from said level below said top level such that said at least one third rail extends above said top level of said scaffolding.
19. A protection bar for attachment across gaps in scaffolding support structure, comprising:
- (a) an elongate member; and
- (b) a scaffolding interconnection bracket depending from each end of said elongate member, each said scaffolding interconnection bracket being so arranged as to be attachable to an upright scaffolding member when said protection bar is inclined from the horizontal and so as to be, after being attached to said upright scaffolding member, non-detachable from said upright scaffolding member when said protection bar is oriented horizontally.
20. The protection bar of claim 19, wherein each said scaffolding interconnection bracket comprises a U-shaped retaining bracket having a base attached at an end of said elongate member so as to be substantially orthogonal to said elongate member and two sides extending longitudinally from said base away from said elongate member, said two sides being sufficiently spaced from one another to permit an upright scaffolding member to be received between them.
21. The protection bar of claim 20, wherein each said scaffolding interconnection bracket further comprises a support bracket having a transverse leg extending transversely across an open end of said U-shaped retaining bracket, said transverse leg being sufficiently longitudinally spaced from said U-shaped retaining bracket to allow an upright scaffolding member to be received therebetween.
22. A telescoping bar for attachment across gaps in scaffolding support structure, comprising:
- (a) a tube;
- (b) a telescoping rod slidably received within a first end of said tube;
- (c) biasing means mounted within said tube so as urge said telescoping rod to slide outwardly from said tube;
- (d) limiting means to limit the outward sliding of said telescoping bar from within said tube;
- (e) a first scaffolding interconnection bracket affixed to a second end of said tube; and
- (f) a second scaffolding interconnection bracket affixed to the outer end of said telescoping rod.
23. The safety apparatus capable of claim 22, wherein said first and second scaffolding interconnection bracket each comprise a U-shaped bracket capable of receiving an upright scaffolding member.
24. A plank moving tool comprising:
- (a) a lower arm;
- (b) an upper arm parallel with said lower arm and offset rearwardly with respect to said upper arm; and
- (c) a handle extending below said lower arm.
25. The plank moving tool of claim 24, wherein said lower arm has at least one upwardly directed plank gripping element.
26. The plank moving tool of claim 25, wherein said at least one upwardly directed plank gripping element comprises a plurality of teeth.
Type: Application
Filed: Sep 7, 2001
Publication Date: Mar 13, 2003
Inventor: Danny Panacci (Markham)
Application Number: 09947497
International Classification: E04G001/16; E04G005/00;