Fire escape – ladder – or scaffold – Traversing – track-mounted
Reexamination Certificate
1998-02-27
2001-08-07
Stodola, Daniel P. (Department: 3634)
Fire escape, ladder, or scaffold
Traversing, track-mounted
C212S346000
Reexamination Certificate
active
06269904
ABSTRACT:
CROSS-REFERENCE TO RELATED APPLICATIONS
Not Applicable
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not Applicable.
BACKGROUND OF THE INVENTION
This invention relates to fall protection systems, and in particular, to a truss-style trolley beam for fall a protection system.
The fall protection equipment industry in both the United States and abroad manufactures and installs several types of overhead fall protection systems. Fall protection systems are typically, though not exclusively, used to prevent workers from accidental falls from the tops of railroad cars, tanker trucks and similar rolling or stationary vehicles (used primarily during loading/unloading), and other stationary structures such as at the tops of tall silos and buildings and other structures that, while being traversed, provide fall hazards and may require supplemental protection for workers who traverse them.
Virtually all fall protection systems typically include a safety harness (which is worn by the user of the system) which is secured to a lanyard (often a spring loaded retractable webbed belt feeder) to restrain the worker from falling. The lanyard is also commonly referred to as a “lifeline”. The lifeline portion of the lanyard is usually manufactured of nylon woven belt webbing or stainless steel cable. The safety harness is normally manufactured of nylon webbing material and is designed to distribute the loading stresses of a fall arrest toward the seat and thighs of a worker, thus preventing serious injury in the event of a fall.
Most applications for these systems also allow the worker to move with ease about the structure or vehicle being traversed, and the majority of these systems therefore include some sort of trolley, or traversing mechanism, which allows the worker to tether himself to the system and move about while maintaining constant protection in the event of a fall.
The most common fall protection system currently in use today is the “safety cable” system. In this system, a stainless steel cable (or a similar cable made of a synthetic material) is securely strung between two or more anchor points. A trolley mechanism is mounted on that cable to secure the lanyard and therefore support the worker in the event of a fall.
A second type of fall protection system, in limited commercial use today, is the trolley beam (or I-Beam) style system. The typical I-beam style fall protection system includes an I-beam supported above the structure to be traversed, a trolley which rides on the I-beam, and a safety harness which is worn by the worker. The trolley in the I-beam system is typically a four-wheeled device that is designed to ride on the lower leg or flange of the I-beam, and includes an attachment point (typically a carabiner) to secure the lifeline to the trolley.
Due to static loads and the loads placed on the I-beam when a worker falls, the I-beam is prone to flexing, sagging, drooping, warping or otherwise distorting. To overcome this, supporting members have to be installed every 6′-7′ feet along the length of the I-beam to prevent the I-beam from flexing or otherwise distorting. Further, because of the flexing, the I-beam systems typically have a maximum weight allowance. These factors severely limit where I-beam style systems can currently be installed. Practical applications are limited to those in which the I-beam rail can be directly and securely attached to an existing structure. The only previously known and recognized means of mounting the I-beam was to hang the I-beam over the planned area by attaching it with bolts or welds directly onto existing steel roof beams, perlins, or other similar pre-existing structures already in place at the point of installation. Because of these limitations to the I-beam style fall protection system, the safety cable fall protection system has dominated the industry.
BRIEF SUMMARY OF THE INVENTION
A primary object of the present invention is to provide an I-beam style trolley fall protection system.
Another object is to provide such a fall protection system which can span long distances (i.e., more than about fifteen feet) without the need for frequent supports.
A further object is to provide such a fall protection system which can be made to be free standing.
A further object is to provide such a fall protection system which reduces the tendency of the I-beam to sag or bend.
These and other objects will become apparent to those skilled in the art in light of the following disclosure and accompanying drawings.
Until the invention of my integrated truss style trolley beam, most potential applications for fall protection systems were considered impractical for an I-beam type of fall protection system due to the above noted limitations in the system. Briefly, my integrated truss style trolley beam is a unique and innovative engineering development which integrates a standard I-beam into a custom designed, uniquely self-supporting structure, which can effectively span long distances while providing strong support for the I-beam.
The fall protection system comprises at least two spaced apart support members, a rail assembly mounted to the support members to be positioned over a work area, a trolley slideable along the rail assembly, a lanyard suspended from the trolley, and a harness connected to an end of the lanyard and adapted to be worn by a user. The support members are spaced at least 10′ feet apart (and upwardly of 45-50′ apart) and support the rail assembly above a structure to be traversed.
The rail assembly includes a beam and a truss member. The beam has a generally horizontal web secured to a bottom of the truss member. The trolley is slideable over or along the horizontal web of the beam. The truss member is mounted to a top of the beam and extends substantially the length of said beam.
The truss includes a truss frame having a first frame member and a second frame member which are spaced apart from each other above the beam. The frame members extend generally horizontally substantially the full length of the beam. The truss includes a plurality of connecting members extending between the first and second frame members in a zigzag fashion. The truss is completed by a second and third set of connecting members. The second set of connecting members extends between the first frame member and the beam. The third set of connecting member extends between the second frame member and the beam. The second and third set of connecting members also zigzag between the frame members and the beam to define a plurality of triangles. Preferably, the truss is generally triangular in end elevation. The lower or bottom ends of the second and third sets of connecting members thus converge toward each other and are located substantially adjacent each other at the point where they are connected to the beam. The frame members preferably are made from angles having an upper leg and a lower leg. The upper leg is generally horizontal and the lower leg defines an acute angle (preferably about 60°) with the upper leg. The second and third sets of connecting members are fixed to the frame member second legs. The angle defined by the legs is sized to direct the second and third sets of connecting members to the approximate center of the beam.
The truss is suspended from the support by a bracket assembly. The bracket assembly includes a bracket cross-member which extends between the frame members and a U-bolt to which the cross-members are connected. The U-bolt has a pair of legs connected by a spanner. The U-bolt legs extending downwardly from said support to be connected to the bracket cross-members. Preferably, the bracket includes a spacer on an upper surface of each frame member. The bracket cross-members are mounted to the spacer to be spaced above a top of said truss.
REFERENCES:
patent: 2639950 (1953-05-01), Wheeler
patent: 3294252 (1966-12-01), Hosoi et al.
patent: 3844417 (1974-10-01), Holm
patent: 3870122 (1975-03-01), Faucheux
patent: 4702661 (1987-10-01), Bisiach
patent: 4890750 (1990-01-01), Stern
patent: 543315
FPS Investments, LLC
Polster, Leider, Woodruff & Lucchesi
Stodola Daniel P.
LandOfFree
Truss style trolley beam for a fall protection system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Truss style trolley beam for a fall protection system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Truss style trolley beam for a fall protection system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2517706