BACKGROUND OF THE INVENTION
Field of the Invention
The invention pertains to the field of construction safety equipment. More particularly, the invention pertains to safety railings and apparatus for mounting such railings.
SUMMARY OF THE INVENTION
The present invention is a support system for attaching safety railings, especially useful on construction sites. A clamp allows attachment to beams or posts of differing sizes, squeezing the beam or post using mechanical fasteners and, optionally, shims or spacers. A support arm is mounted on the clamp, and posts for railings that are removably mounted to the support arm.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 shows an exploded view of the parts of one embodiment of the invention.
FIG. 2 shows a detail of the clamp of the invention, within the box 2-2 of FIG. 1.
FIG. 3 shows the invention mounted on an I-beam.
FIG. 4 shows the invention mounted on a post.
FIG. 5 shows an exploded view of the parts of a second embodiment of the invention.
FIG. 6 shows a cut-through view of the second embodiment of the invention, along the lines 6-6 in FIG. 5.
FIG. 7 shows a cut-through view of the second embodiment of the invention, along the lines 7-7 in FIG. 5.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a view of the safety railing support system of the invention. The system is used for attaching safety railings, especially useful on construction sites. FIG. 2 shows a detail of the clamp portion of the invention, from the portion of FIG. 1 enclosed in dotted box 2-2. FIG. 3 shows the clamp portion of the invention in use on an I-beam.
The clamp is made up of a clamp base 1 and fastening plates 2. Shims or spacers 3 are provided to keep the clamp aligned when it is in use. Slots or holes 5 in the base plate allow passage of mechanical fasteners such as bolts 22, which are threaded into holes 7 in the fastening plates 2. Alternatively, the holes 5 in the clamp base 1 could be threaded, and the holes 7 in the fastening plates 2 could be made large enough to pass the bolts 22, in which case the bolts 22 would be tightened from the reverse side. Optionally, the holes 7 in the fastening plate and the holes 5 in the clamp base could both be made larger, and nuts (not shown) could be threaded onto the bolts 22. Holes 5 are preferably made as elongated slots, as shown in the figures, so as to allow the clamp to be used on different sized beams or posts.
A support arm 4 is mounted on the clamp, preferably by having one end welded onto the clamp base 1. The support arm 4 is preferably of square stock as shown in the figures, or could be made of I- or U-channel as desired. A number of holes 9 allow attachment of an upright post 10 by passing a fastener 14 through holes 13 in flanges 11 and holes 9 in the support arm 4. The fastener 14 could be a bolt as shown, secured in place with nut 15, or the holes in the other flange 11 could be threaded to accept the bolt. Alternatively, the fastener 14 could be a clevis pin or other suitable fastener, held in by a cotter pin or clip, or any other arrangement known to the art. Holes 12 in the upright post 10 allow passage of a safety wire (not shown) connecting a plurality of upright posts 10 to form a safety railing.
As can be seen in FIG. 3, the invention can be used to attach the support arm 4 on the clamp base 1 to a flange 21 of an I-beam 20. The clamp base 1 is placed against the outside of the flange 21, and fasteners 22 on each side of the beam are passed through slots 5 and threaded into holes 7 in fastening plates 2 behind the flange 21. Shims or spacers 3 of approximately the same thickness as the flange 21 are put in place, the slots 6 in the shims 3 allowing the shims 3 to slip over the fasteners 22. The fasteners 22 are slid inward in the slots 5 until the shims 3 are close to the edges of the flange 21, and then are tightened to clamp the flange 21 securely between the clamp base 1 and fastening plates 2.
FIG. 4 shows an alternative use, in which the invention is used to attach support arm 4 to a square post 25. As with the I-beam flange 21 above, the clamp base 1 is placed against the post 25, and the fasteners 23 (which need to be longer than the fasteners 21 for I-beams) are threaded into holes 7 in fastening plates 2 behind the post. The fasteners 23 are slid inward in the slots 5 until they are close to the sides of the post 25, and then are tightened to clamp the post 25 securely between the clamp base 1 and fastening plates 2.
FIG. 5 shows a view of a second embodiment of the invention. The clamp system in this embodiment is the same as in FIGS. 1-4, and will not be separately described here.
The embodiment of FIGS. 5-7 differs from the first embodiment in several ways, each variation of which may be used independently or in combination with the embodiment of FIGS. 1-4.
First, as shown in FIGS. 5 and 7, this embodiment differs in how the upright post 10 fastens to the support arm 4. Specifically, instead of bolt 14 passing through holes 9 in support arm 4 as in the first embodiment, in this embodiment holes 13 in flanges 11 are placed lower down, such that bolt 14 passes below support arm 4. Upright post 10 can slide on support arm 4 as before, but instead of being limited to the locations of pre-drilled holes 9, it can be fastened in place at any point along the arm by tightening nut 15 and bolt 14, squeezing arm 4 between flanges 11.
FIGS. 5 and 6 show an alternative method of fastening a safety wire 39 (not shown in FIG. 5) to the upright post 10. In this embodiment, the upright post 10 is formed with a longitudinal slot 30 running along one side of the post 10—preferably, as shown here, the inner side closer to the clamp, although it could also be placed on the opposite side. The slot could simply be cut or otherwise formed up one side of a square or rectangular box post 10. Preferably, though, as shown in FIGS. 5 and 6, post 10 is extruded with a hollow rectangular portion 32 and a “T” shaped slot, having a side-to-side portion 31 and longitudinal slot 30 running from portion 31 to the outside of the extrusion.
A fastener 36 having a head 33 is placed with the head 33 through longitudinal slot 30, the head extending into the side-to-side portion 31. Fastener 36 passes through a hole in a wire grip plate 35, and a nut 34 is threaded onto the fastener. While a flat plate 35 could be used, it is preferable to provide a wire groove 38 into which wire 39 can fit. When the plate 35 on fastener 36 is slid into the desired vertical position along post 10, and nut 34 is tightened onto fastener 36, wire 39 is gripped by wire grip plate 35 and held securely against the post 10.
While only one plate 35 and fastener 36 is shown in FIG. 5, it will be understood that multiple wire grip plates 35 and fasteners 36 could be provided within the teachings of the invention, to provide for however many safety wires 39 are desired.
Finally, as seen in FIG. 7, the same form of extrusion shown for the upright post 10 in FIG. 6 can also be used for the support arm 4. The extrusion is extruded with a hollow rectangular portion 41 and a “T” shaped slot, having a side-to-side portion 42 and longitudinal slot 43 running from portion 42 to the outside of the extrusion along the length of support arm 4. This allows a wire support ring 46 to be threaded onto the end of a fastener 45 which is slid into slot 43. The head 44 of the fastener 45 fits in side-to-side portion 42, and once it is slid into the desired position along support arm 4, nut 47 can be tightened to hold the fastener 45 in place in slot 43.
A safety wire (not shown) can then be threaded through ring 46, and additional rings 46 and fasteners 45 can also be provided, so that one or more safety wires can be provided along the length of the arm 4. The same ring 46 and fastener 45 arrangement could also be slid into the slot 30 on upright post 10 and fastened in place by nut 47, as an alternative to the wire grip plate 35 or in addition to one or more wire grip plates 35, or as a location to clip a safety rope, or any other reason where a ring would be desirable.
Accordingly, it is to be understood that the embodiments of the invention herein described are merely illustrative of the application of the principles of the invention. Reference herein to details of the illustrated embodiments is not intended to limit the scope of the claims, which themselves recite those features regarded as essential to the invention.