Patent Application
20090020363
1. Field of the Invention
The present invention is directed to a fall protection system for scaffolding and to covered scaffolding with a fall protection system.
2. Description of the Prior Art
Portable scaffold systems are well know and used widely in the construction and maintenance industries, providing elevated access for workers to walls, buildings and other structures. The particular configuration of the scaffolding varies depending upon the use with different heights, widths and sizes to match the particular structure that is worked on. Moreover, scaffolding that is used outdoors may require an enclosure when weather makes working on a scaffold system difficult and potentially dangerous if there is not some protection from the elements.
As a safety precaution, a safety railing or other barrier should extend above and along the platform. Although such barriers are helpful, working conditions and regulations often also mandate personal fall arrest systems for many jobs. Such personal fall arrest systems include some type of anchor and a lifeline attached to a worker wearing a harness. These systems prevent serious injury should the worker fall from the scaffolding platform. It is advantageous if such an anchoring system provides a line to the worker while still allowing the worker to be anchored in such a manner that the anchor point may be moved along the platform. Such an arrangement decreases the amount of time that the worker must spend detaching and reattaching the lifeline.
Gaps, such as openings for doors in a masonry wall being constructed, present additional hazards as the safety of the wall is removed and workers may fall through these gaps. Outriggers may be mounted to extend from the side of the scaffolding in some configurations where gaps would exist. However, it is not always possible to use such extensions and gaps of up to three feet may exist. Moreover, erecting a railing on the inner portion of scaffolding to provide protection at these gaps may be impossible or impractical and/or may not work with all types of scaffolding and fall protection systems. Similar design issues may arise at edges of buildings.
Although the prior art shows many barrier type systems, it can be appreciated that such systems do not provide for anchoring a lifeline allowing the lifeline to slide, providing freedom of movement for the workers while maintaining worker safety at a high level that meets the relevant standards in scaffold systems. Typically, such standards may require limiting the freefall to six feet, having a deceleration limit of three and a half feet, and being able to withstand twice the potential impact generated by an employee when falling a distance of six feet. Codes and standards often require such safety systems where the platform height is more than ten feet above the ground.
Further difficulties arise in providing a safe working environment when the scaffold system must be enclosed. Typically, a tarp like cover is often fitted over the scaffold frame. Such a cover may have additional supports and may be connected to the building or structure to protect the workers from the elements. Codes and regulations may dictate that the workers are equipped with a fall protection system while fitting the cover over the scaffolding. Moreover, once the cover is in place, the operability of the fall protection system should not be limited by the cover.
It can be appreciated that a new fall protection system for scaffolding is needed. Such a system should provide workers freedom of movement while maintaining adequate fall protection. Such a system should provide access and freedom of movement along a platform while limiting the distance of a fall should an accident occur. Moreover, such a system should be compatible with scaffolding wherein a cover is placed over the scaffold frame. Such a system should be compatible with conventional scaffolding and multiple wall configurations and should be easy to install and remove. The present invention addresses these as well as other problems associated with worker fall protection for scaffolding arrangements.
The disclosure is directed to a scaffold system and more particularly to scaffolding having a fall protection system. The scaffolding includes conventional scaffolding frame sections that are joined together to support elevated platforms. The scaffolding includes a fall protection system with a safety cable on spaced apart supports maintaining the safety cable above each platform. The safety cable provides a sliding connection to an arrest system for each worker.
The fall protection system includes cable supports, including end cable supports forming a short tube type member through which the safety cable passes. The intermediate cable supports include guide rings interacting to retain the safety cable, but which do not form a continuous closed ring around the cable. The guide rings are spaced apart arcing elements, with radially overlapping profiles so that the safety cable is retained. However, the opening between the guides allows for the arrest system to slide along the cable and pass between the guide ring elements without detachment from the cable. This configuration allows a worker to slide line clips of the arrest system along the safety cable without having to be detached from the safety system.
The cable supports include a riser extending vertically and an upper support mount and lower support mount detachably mounting the cable support posts to the scaffolding frame. Each of the support mounts includes pin-type connectors and associated mounting holes that provide for rigid attachment at two spaced apart positions to the scaffolding frame.
In some embodiments, the scaffolding system includes a cover. An additional cover frame may mount to the scaffolding frame and support the cover. The scaffolding frame is configured to allow workers to stand while working, but may not extend as high as the upper ends of the safety cable supports. Therefore, the safety system is above and outside of the cover. The cover may generally be a tarp that is joined along a seam or seams and the safety cable supports are spaced such that the risers are aligned with and extend up through a seam of the cover. The cover provides a barrier to the elements and a roof over the workers. The cover may be anchored in several configurations depending upon the work site and the type of work performed.
In addition, it can be appreciated that in some embodiments, the cover may be placed over the safety cable supports and the safety cable. With this configuration, the scaffolding and the safety system are totally enclosed.
As mandated by safety codes in many areas, covering of a scaffolding system requires that the workers be attached with a safety device during the installation. Therefore, as the scaffolding is erected, the safety system is also attached and the workers can be safely connected while putting the cover over the scaffolding system.
The safety cable is quickly and easily attached by forming a loop with two cable clamps or similar devices at each end and securing a loop around a portion of the scaffolding frame to provide a secure anchor at each end. The cable must be threaded through the tube portion of the end safety cable supports. However, the guide rings allow for simply angling the cable clips to pass under both ends of the guide ring elements and be centered in the guide rings. This configuration saves time for cable placement and still retains the cable in a safe manner. The other end of the cable is passed through the tube portion of the second end attachment and is also secured to the scaffolding frame by forming a loop with the cable and passing it around a frame member.
These features of novelty and various other advantages that characterize the invention are pointed out with particularity in the claims annexed hereto and forming a part hereof. However, for a better understanding of the invention, its advantages, and the objects obtained by its use, reference should be made to the drawings that form a further part hereof, and to the accompanying descriptive matter, in which there is illustrated and described a preferred embodiment of the invention.
Referring now to the drawings, wherein like reference letters and numerals indicate corresponding structure throughout the several views:
Referring now to the Figures and in particular
The scaffold system 20 also includes a fall protection system, generally designated 30. The fall protection system 30 includes a series of safety cable supports 34 extending upward from the scaffold system frame 22. The safety cable support posts 34 retain and support a safety cable 32 extending generally horizontally above and parallel to each platform 24. The safety cable supports 34 include tube like or ring like end guides 36, while intermediate guides 38 between the ends include guide rings 38. The safety cable 32 passes through tube portions of the end attachments 36. The safety cable 32 also passes between guide ring elements 39 on the intermediate guides 38 and is secured to the frame 22, as shown in
As shown in
Attachment of the safety cable 32 to the scaffolding frame 22 is fast and simple. A loop is formed in an end of the safety cable 32 that passes around a horizontal portion of the frame 22 and is securely closed with two cable clamps 68. After a first end is secured, the cable 32 is passed through the guides 36 and 38 and a loop is formed in the second end of the cable 22, which passes around a portion of the frame 22 and the second end is securely closed with two additional cable clamps 68. For some configurations, particularly those spanning a long distance, the cable 32 may become too heavy to pull by hand due to its length. Therefore, a hand operated winch or device may be used to tighten the cable and provide sufficient tension in the safety cable 32 to eliminate sagging.
As shown in
It can be appreciated that with the guide ring elements 39, a worker may slide the arrest system along the safety cable 32 by maneuvering the clips 48 between the opposed slightly overlapping members 39 of the guide ring 38, shown in
In addition to the arrest system 40 mounting to the safety cable 32 and absorbing some the force from a worker's fall, the cable supports 34 are also designed so that the riser 50 may deform and bend downward from the impact and force of a fallen worker exerted on the fall protection system 30, as shown in phantom in
Referring now to
As shown in
During assembly, the scaffold system 20 is erected by attaching various scaffold frame members 26 together. The scaffold system 20 is generally configured so that there are complementary sections that align and engage one another in a conventional configuration. Additional tightening and support further strengthens and reinforces the scaffold system 20. Platforms 24 are added as the scaffold frame 22 is erected. The fall protection is system 30 is preferably erected as the scaffold system 20 is erected as regulations may require that workers must have a form of fall protection while this work is being performed and typically require that fall protection is in place while the cover 70 is being placed over the scaffold system 20 and attached thereto. The fall protection system 30 may be erected and raised from level to level with the addition of individual levels of the scaffold system 20. Cable safety supports 34 easily attach to the scaffold frame 22 by aligning the cable support 34 to the frame and inserting the pins 54 and 64 into the respective folds 56 and 66. The safety cable 32 is attached to the scaffold frame 22 and then strung through the end attachment 36 and the guide rings 38 to the end attachment 36 at the second end of the scaffold system 20 and then looping around and securing the second end of the safety cable 32 to the frame 22. If a cover 70 is placed over the scaffold system, that work is performed after the fall protection system 30 is in place. In this manner, the workers are safely secured to the scaffolding 20 while the cover 30 is secured over the scaffolding 20.
Referring now to
Referring now to
Referring now to
In an embodiment shown in
As can be appreciated, the present invention provides flexibility for providing a safety system allowing mobility for the workers. Moreover, the system allows for enclosing the scaffolding framework and adapting to mounting to different types of walls for different types of jobs and applications while maintaining mobility and safety.
It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
