Moveable safety handrail system

Abstract

A safety device and methods for providing fall protection during the installation of roofing panels. A moveable safety handrail system includes a pair of safety rails that are supported in a generally horizontal orientation by a plurality of outrigger assemblies. The outrigger assemblies each include a support portion for support of the rail members and a rolling frame portion that engages the purlins of a rooftop structure in rolling contact. The handrail system also features a braking system that prevents inadvertent movement of the handrail device upon the rooftop understructure.

Description

[0001] This application claims the priority of U.S. provisional patent application no. 60/362,176 filed Mar. 6, 2002.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The invention relates to a movable safety handrail system for use in installing metal roofing on a building. The invention also relates to methods for safely installing metal panels to a rooftop understructure.

[0004] 2. Description of the Related Art.

[0005] A basic metal roof structure uses one or more sheets of insulation atop a series of parallel purlins and metal panels that are laid atop the insulation and then secured to the purlins. The roof structure is installed by workers who typically move from one end of the building to the other, laying down insulation and metal panels as they go.

[0006] The installation of metal building roofs can be a hazardous undertaking for workers as the potential for falls exists. One of the most potentially hazardous areas is the “leading edge” of the metal panels wherein the workers are typically concentrated and working to lay insulation and affix the metal panels to the purlins. Existing methods for protecting workers from falls are either overly costly or present practical problems in use.

[0007] U.S. Pat. No. 6,003,282 issued to Alderman et al. describes a moveable safety barrier with a handrail for use during the placement of metal roofing panels. Alderman describes a carriage having rollers that are mounted for rolling along the top of the purlins during construction of a metal panel roof structure. The carriage features a deck for workers to stand on while they work. The During operation, the insulation and support material are dispensed from the rolls between the leading edge of the metal roof and the framework of the carriage.

[0008] Alderman's device, while useful, has a number of operational drawbacks. Support sheets and optional support plates that are placed between the leading edge and the framework of the carriage provide fall protection. This is expensive and time consuming. Further, in order to dispense insulation and support sheet material from the rolls and/or to operate the winch to relocate the carriage, workers will move over the gap created between the metal panels already placed and the deck of the carriage. This exposes the workers to a risk of falling. If the optional support plates are not in place when the workers are moving, or if the support plates are improperly placed, the worker might fall through the gap without sufficient fall protection.

[0009] U.S. Pat. No. 6,216,416, issued to West al. describes a metal roof installation system having an installation assembly with a handrail that can be moved across the purlins of a rooftop understructure. The installation assembly includes a material handling assembly and a working deck that are secured together and mounted upon rollers for rolling lateral movement across the rooftop substructure. The working deck underlies the metal roof panels. Workers stand upon the working deck while securing metal roof panels to the roof. The material handling assembly includes a series of parallel rollers that are aligned with one another to permit items to be rolled from one end of the roof to a desired spot upon the rooftop.

[0010] The West system is also useful. However, it also has a number of problems that prevent it from providing an optimal solution. The use of a working deck that is disposed beneath the metal roof panels is cumbersome in practice and may tend to become hung up with the insulation disposed below the roof members and even damage the insulation during movement of the installation assembly across the rooftop.

[0011] Both the Alderman and West devices incorporate decks or platforms upon which workers may stand during construction of the roof. This is undesirable for several reasons. First, it materially increases the weight of the device and necessitates the use of a separate prime mover to translate the device across the rooftop. Both Alderman and West teach the use of a winch for movement of their platforms across the length of the rooftop. The requirement for a winch increases the cost of the rooftop safety system substantially. Even without the weight factor, it is, as a practical matter, difficult or impossible for workers to move a device such as the ones described in the Alderman and West across the roof. The workers must stand on the deck or platform in order to reach the handrail, and the fact that the workers are standing on the deck or platform, precludes movement.

[0012] Also, prior art handrail systems typically use rollers that simply ride atop the purlins. During use, the rollers might become disengaged from the purlins. Further, there is no positive braking mechanism for these handrail systems. As a result, inadvertent movement of the handrail is possible, thereby allowing falls to occur.

[0013] A solution to the problems of the prior art would be desirable.

SUMMARY OF THE INVENTION

[0014] The present invention provides an improved safety device as well as improved methods for providing fall protection during the installation of roofing panels. In a currently preferred embodiment, a moveable safety handrail system includes a pair of safety rails that are supported in a generally horizontal orientation by a plurality of outrigger assemblies. The outrigger assemblies each include a support portion for support of the rail members and a rolling frame portion that engages the purlins of a rooftop structure in rolling contact. The exemplary handrail system described also features a braking system that prevents inadvertent movement of the handrail device upon the rooftop understructure.

[0015] In operation, the handrail portion of the handrail device is positioned at or very proximate the leading edge of the metal roof panels, thereby providing security against falls. The support portions for the handrail device are advantageously placed on the side of the handrail opposite where a worker is working, thereby preventing a worker from tripping over support struts and the like.

[0016] The invention also provides the advantages of simplicity in construction and operation. Because there is no platform affixed to the handrail device upon which workers are to stand, the handrail device is typically light enough to be moved manually, without the need for a winch or other prime mover.

[0017] It is an object of the present invention to provide a safety handrail system that can be translated across the length of a rooftop under construction by workers manually without the need for a prime mover, such as a winch. It is also an object of the invention to provide a safety handrail system that is simple and inexpensive to construct.

[0018] It is a further object of the invention to provide a safety handrail system having improved interengagement with the purlins of a rooftop understructure, and a self-braking mechanism to preclude inadvertent movement of the handrail device during use.

[0019] It is yet another object of the invention to provide a safety handrail system wherein the handrail lies adjacent to, or very proximate to, the leading edge of the metal roof panels during construction, thereby eliminating the presence of a dangerous gap between the handrail and the leading edge.

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The advantages and further aspects of the invention will be readily appreciated by those of ordinary skill in the art as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings in which like reference characters designate like or similar elements throughout the several figures of the drawing and wherein:

[0021] FIG. 1 is an isometric view of an exemplary movable safety handrail system constructed in accordance with the present invention.

[0022] FIG. 2 is a close up isometric view of one of the roller portions of the safety handrail system shown in FIG. 1.

[0023] FIG. 3 is a detail view showing a roller assembly and braking device.

[0024] FIG. 4 is a side cross-sectional view illustrating engagement of the roller assemblies and brake device with purlins of the roof line.

[0025] FIG. 5 is a further detail view showing, in cross-section, engagement of a braking plate with a purlin.

[0026] FIG. 6 is a side cross-sectional view of an outrigger portion of the handrail system.

[0027] FIG. 7 depicts an alternative engagement structure for a safety handrail system constructed to be supported upon T-shaped bar joists.

[0028] FIG. 8 is a close up detail of portions of the system shown in FIG. 7.

[0029] FIG. 9 is a front view detail of an exemplary braking mechanism used in the safety handrail system shown in FIGS. 7 and 8.

[0030] FIG. 10 is a side view detail of the braking mechanism shown in FIG. 9.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] Turning first to FIGS. 1-6 there is shown an exemplary movable safety handrail assembly 10 which, in FIG. 1, is shown to be installed upon the rooftop structure 12 of a building that is being constructed. The rooftop structure 12 includes a plurality of parallel, I-beam rafters 14 and a plurality of parallel purlins 16 that are disposed atop the rafters 14 at right angles thereto. The purlins 16 have a reverse S-shaped cross-section, which as may be seen best in FIGS. 4 and 5, includes a central web 16A and upper and lower flanges 16B, 16C, respectively. As FIG. 1 shows, a layer of insulation 18 has been laid atop the purlins 16, and a layer of corrugated metal panels 20 overlies the insulation 18. The metal panels 22 are secured by connectors (not shown) to the purlins 16. In FIG. 1, the insulation 18 and metal panels 20 extend only partway across the rooftop structure 12, indicating that construction of the building roof is ongoing. Workers typically stand upon the metal panels 20 to insert connectors that secure the metal panels 20 to the purlins 16. The metal panels 20 present a leading edge 22, the location of which changes as additional metal panels 20 are affixed to the purlins 16. As the general mechanics of placement for insulation and metal roofing materials are well understood, they will not be described further here.

[0032] The handrail assembly 10 includes a pair of tubular safety rails 24, 26 that are disposed in a parallel, spaced relation to one another, one above the other, to provide protection from falls to workers. The rails 24, 26 are secured in moveable relation to the purlins 16 by a plurality of outrigger assemblies 28. Three outrigger assemblies 28 are shown in FIG. 1. Each outrigger assembly 28 includes a rectangular, horizontal rolling frame portion 30 and a vertically disposed, triangular support portion 32. The rolling frame portion 30 consists of a pair of roller assemblies 34 that are adjustably interconnected via lateral struts 36. During use, the roller assemblies 34 reside atop adjacent purlins 16 as FIG. 1 illustrates. The roller assemblies 34 feature a carriage housing 38 that is made up of welded cross-members and retains an axle 40 about which roller 42 rotates. During use, the roller 42 rollingly engages the upper surface of the top flange 16B of a purlin 16, as best illustrated in FIGS. 3 and 4.

[0033] A friction brake shoe 44A is secured, preferably by bolting, to the end of the carriage housing 38 that is proximate the safety rails 24, 26. A second friction brake shoe 44B is secured to the opposite end of the carriage housing 38. The friction brake shoes 44A, 44B have the same construction, which is best appreciated by reference to the exemplary brake shoe 44 shown in FIG. 5. The exemplary plate 44 is square or rectangular having a square or rectangular cut-out portion 46 at its center so that a downward-facing frictional engagement surface 46A is formed proximate the upper end of the plate 44, and an upward-facing frictional engagement surface 46B is formed proximate the lower end of the plate 44. There is a slot 48 located off-center within the lower side of the plate 44. As FIG. 5 shows, the brake shoe 44 is slidingly engaged with a purlin 16 by disposing the upper flange 16B of the purlin 16 within the cut-out portion 46. Rolling movement of a roller assembly 34 is inhibited when either of the engagement surfaces 46A or 46B of the brake shoes 44A or 44B are brought into frictional engagement with the upper flange 16B of the purlin 16.

[0034] The handrail assembly 10 is self-braking since the natural balance of the assembly 10 will bring the engagement surfaces 46A and 46B of the brake shoes 44A, 44B into frictional engagement with the purlins 16. FIG. 6 shows that the pivot 40 of the roller 42 for an exemplary roller assembly 34 is approximately balanced (L1=L2), however, the additional weight of the safety rails 24, 26 and the portions associated with them cause the engagement surface 46A of the brake shoe 44A to be brought into contact with the flange 16B while the engagement surface 46B is also brought into contact with the flange 16B.

[0035] The carriage housings 38 are adjustably secured to the cross-members 36 so that the distance between the carriage housings 38 can be easily varied to account for variations in spacing between purlins 16. Referring now to FIG. 4, it can be seen that the cross-member 36 contains a plurality of apertures 50. The carriage housings 38 may be secured to the cross-member 36 using a pin or another suitable securing member 52, such as those shown in FIGS. 2 and 3. The securing member 52 is inserted through a selected aperture 50 and a corresponding aperture (not shown) in the carriage housing 38 to secure the carriage housing 38 at a selected location on the cross-member 36. Because there are a plurality of apertures, the distance between the carriage housings 38 may be adjustably varied (as arrows 39 in FIG. 4 illustrate) to account for different purlin spacings.

[0036] An alternative embodiment for a safety handrail system 10′ is depicted in FIGS. 7-10. Construction of the alternative safety handrail system 10′ is identical to the safety handrail system 10 except where indicated otherwise. Like components between the two embodiments are provided with like reference numerals. With this embodiment, bar joists 16′ are used rather than the purlins 16 described earlier. As FIGS. 7 and 8 depict, the bar joists 16′ have a T-shaped cross-section wherein there is a large, upper rectangular portion 54 and a lower, downwardly-projecting portion 56. The braking mechanism of the alternative handrail system 10′ is best shown in FIG. 8 as well as 9 and 10. The brake shoes 44′ feature a cross-piece 58 that, during use, is positioned atop a bar joist 16′. Additionally, a pair of gripping flanges 60, 62 will reside proximate the lower side of the bar joist 16′. These portions of the brake shoes 44′ may be selectively brought into frictional engagement with the upper and lower sides of the bar joist 16′ in order to prevent rolling movement of the handrail system 10′ along the bar joists 16′ of a rooftop structure. It is noted that the handrail systems 10 and 10′ of the present invention are useful as OSHA-recognized handrail systems rather than as fall protection systems. In a currently preferred construction, the handrail systems 10, 10′ are suitable to prevent a fall by a 200 pound man.

[0037] In operation, the handrail assembly 10 or 10′ is constructed upon the rooftop structure of a building to be roofed or decked. The assembly 10, 10′ is constructed so that the safety rails 24, 26 lie parallel with the rafters 14, and the supporting outriggers 32 of the assembly 10, 10′ are rollingly engaged with adjacent purlins 16 or bar joists 16′. The purlins 16 and bar joists 16′ may be considered to be rooftop understructure members along which the handrail assembly 10 or 10′ is moved. The handrail assembly 10 or 10′ is positioned at or near the leading edge 22 of the metal panels 20. As noted previously, the weight of the safety rails 24, 26 and proximate portions will cause the brake shoes 44, 44′ to frictionally engage the purlins 16 or bar joists 16′ and prevent the handrail assembly 10 or 10′ from inadvertently moving. When it is desired to move the handrail assembly 10 or 10′, this may be done by having workers lift up on the safety rails 24, 26 to tilt the assembly 10, 10′ upon its rollers 42 and thereby disengaging the brake shoes 44 or 44′ from frictional engagement with the purlins 16 or bar joists 16′. The handrail assembly 10 or 10′ may then be manually rolled along the purlins 16 or 16′ to the new desired location. It is intended that the handrail assembly 10, 10′ will be located near the leading edge 22 of the metal plates 20 during essentially the entire roofing operation so that the safety rails 24, 26 may prevent or lessen the chance of a worker falling from atop the metal plates 20.

[0038] The system of the present invention provides a number of advantages. The length of safety rail protection may be made to match the width of the building being roofed by adding or removing the number of outriggers 32 that are used and by cutting the safety rails 24, 26 to size. Alternatively, one may have a plurality of modular rails that are located adjacent to one another and operated in tandem. Additionally, the assemblies 10, 10′ are adjustable to allow them to be installed on rooftops having varied purlin spacing. Further, the system is relatively inexpensive and easy to construct.

[0039] Those of skill in the art will recognize that many modifications and changes may be made to the teachings herein while still remaining within the spirit and scope of the present invention.

Claims

1. A moveable safety handrail system for use in preventing falls proximate a leading edge of a roof panel, the moveable handrail system comprising:

a generally horizontal safety rail member;

at least one outrigger assembly which comprises a horizontal rolling frame portion for rolling engagement with a plurality of rooftop understructure members, and a support portion for supporting the safety rail member.

2. The moveable safety handrail system of claim 1 wherein the rolling frame portion comprises:

a pair of roller assemblies arranged in tandem for rolling contact of separate rooftop understructure members; and

a strut adjustably interconnecting the pair of roller assemblies.

3. The moveable safety handrail system of claim 1 wherein the outrigger assemblies further comprise a friction brake shoe to selectively engage a rooftop understructure member so as to preclude rolling movement of the handrail system along the rooftop understructure.

4. The moveable safety handrail system of claim 3 wherein the friction brake shoe comprises a plate having a cut-out portion for receiving a rooftop understructure member, the cut-out portion further providing a downward-facing engagement surface for frictionally engaging an upper side of a rooftop understructure member and an upward-facing engagement surface for frictionally engaging a lower side of a rooftop understructure member.

5. The moveable safety handrail system of claim 1 wherein there are a pair of safety rail members.

6. The moveable safety handrail system of claim 1 wherein the rooftop understructure members each comprise purlins.

7. The moveable safety handrail system of claim 1 wherein the rooftop understructure members each comprise bar joists.

8. A moveable safety handrail system for providing fall protection proximate a leading edge of a roof panel, the handrail system comprising:

a plurality of outrigger assemblies for contacting a plurality of rooftop understructure members for movement therealong;

at least one safety handrail member supported by the outrigger assemblies to be located proximate a leading edge of a roof panel; and

said moveable handrail system being moved along the rooftop understructure members by manually pushing against the at least one safety handrail member to slide the outrigger assemblies along the rooftop understructure members.

9. The moveable safety handrail system of claim 8 wherein the rooftop understructure members each comprise purlins.

10. The moveable safety handrail system of claim 8 wherein the rooftop understructure members each comprise bar joists.

11. The moveable safety handrail system of claim 8 wherein the outrigger assemblies each comprise a roller member that rollingly engages a rooftop understructure member.

12. The moveable safety handrail system of claim 11 further comprising a brake operably associated with the roller member for selectively frictionally engaging the rooftop understructure member to preclude inadvertent movement of the safety handrail system.

13. The moveable safety handrail system of claim 8 wherein the outrigger assemblies further comprises a rolling frame portion that comprises:

a pair of roller assemblies arranged in tandem for rolling contact of separate rooftop understructure members;

each roller assembly having a carriage housing that retains a roller for rolling contact with a rooftop understructure member; and

a strut laterally interconnecting the pair of roller assemblies.

14. The moveable safety handrail system of claim 13 further comprising a brake shoe mounted on at least one carriage housing for selectively precluding rolling movement of the roller along the rooftop understructure.

15. The moveable safety handrail system of claim 13 wherein the carriage housing has a central portion and two opposite end portions;

the roller is mounted upon the central portion of said carriage housing; and

wherein the handrail system further comprises a pair of brake shoes, each of said brake shoes being mounted upon one of said opposite end portions of said carriage housing, so that the brake shoes may be selectively engaged and disengaged with a rooftop understructure member by pivoting the carriage housing upon the roller.

16. A method of providing fall protection during construction of a paneled roof upon a plurality of rooftop understructure members, the method comprising:

mounting a moveable safety handrail device upon a plurality of rooftop understructure members, the moveable handrail device having at least one safety handrail member for preventing falls proximate the leading edge of a paneled roof being constructed;

moving the moveable safety handrail device along the plurality of rooftop understructure members to maintain the at least one safety handrail member proximate the leading edge;

selectively engaging a brake assembly on the moveable safety handrail device to preclude inadvertent movement of the handrail device.

17. The method of claim 16 wherein the step of moving the moveable safety handrail device comprises rolling the device upon a plurality of rollers.

18. The method of claim 17 wherein the step of selectively engaging a brake assembly further comprises pivoting the safety handrail device upon said plurality of rollers to frictionally engage a brake shoe with a rooftop understructure member.