These inventions improve the design of the current grid structure. The use, safety, and assembly of safe aerial platforms is likewise improved. The present invention is used to allow personnel safe access to high reach areas for mechanical tasks and maintenance operations, such as changing the position of theatrical lights, servicing air conditioning ducts, etc.
The wire rope tension grid has been in use for decades. It is usually installed in performing art centers, black box theaters, and in locations were it is difficult, impossible, or impractical to get a ladder or man lift in an area for maintenance. Through both the use and construction of many wire rope tension grid systems, InterAmerica Stage, Inc. has made various improvements to the structures. Currently we will be releasing a new line of improved wire rope tension grids. These grids will feature both the improvements that have been made over time by our firm and new improvements that have been developed and tested by our engineering staff.
Safety is one of the major reasons the wire rope tension grid is used. It minimizes the risk of falling while performing high reach operations using ladders or lifts. The other major benefit to the wire rope tension grid is that light can pass through without casting shadows on surfaces below it. This is particularly useful in the entertainment industry, where lighting of props, the focus of sound, and special effects placement are of the utmost importance in a performance.
Modularity: A wire rope tension grid is installed as a modular item, able to be removed for service and transported easily for erection. The connections to the modular attachments have been improved. Through-bolts connect hanger points to the grid. This provides a hard connection as opposed to a floating clamped connection. This is a further improvement over the pieces in the past that are non-modular, being welded to their respective support hangers.
Reducing the lateral stress on the wire rope within the wire rope tension grid was a major priority. Rolled edges and chamfered through holes have aided in this regard. Even the position of the hole itself has been reconsidered, and positioned accordingly. The cable is supported over the frame support tube increasing the area of impact and lessening the stress at any particular point in the cable. This allows for a horizontal load to be applied to the wire rope.
Structural strength of the frame has likewise been improved by adding support tabs that do not interfere with the location of the wire rope. These help distribute the vertical and torsion loads that are exerted on the frame while it is in use.
The bottom portion of the hanger connections were further improved, providing streamlined outer perimeter and corner connections for safe handling and aesthetics.
The top of the hanger mounting plates are sized to allow for a flush walking surface.
A lighting pipe outrigger system has been developed applying lighting fixtures or light bars outboard from principal wire rope tension grid suspension points.
Originally, a spacer on the wire rope was used to assist in the swaging of a copper stop sleeve on the wire. With the use of a new purpose built hydraulic swaging tool this is no longer necessary.
Through bolts within the frame allow for a rigid connection to adjacent wire tension grid panels. This helps to prevent the frame from bowing under stresses applied by taut wire rope.
In an instance where a wire rope tension grid system is required to have the wire rope non-perpendicular and non-parallel to the frame, a new way of distributing the wires had to be realized. A wire rope turn pin was added to the frame so that the wire rope can be weaved in the same way that the regular rectangular tension grids. The wire rope turn pin decreases the stress on the cable. Elliptical slots on frame for the cables further lessen pinch points.
Holes 16 are predrilled into the mild steel angle 14 at increments of 2″ center. See
The mild steel angle 14 is welded onto the mild steel tubing 12 making the basic frame structure 28. This basic frame structure 28 is reinforced by supports 30 welded above the locations of the through-holes 18 used for modular attachments.
Basic frame structure 28 is often powder coated or painted, often flat black, so that is not visually intrusive to the general public.
The wire rope 36 is then weaved into the frame by hand. The ends 38 of the wire rope 36 are inserted into the 5/32″ holes. A copper stop sleeve 40 is slid over the ends of the cable. A modified torque wrench is used to apply an accurate amount of tension within the wire rope 36 as the copper stop sleeve 40 is swaged onto the wire rope 36. This is done on both sides of the wire rope 36 resulting in an evenly distributed amount of tension along the entire wire rope tension grid panel 10.
The hanger assembly 50 is comprised of mild steel tubing 52, often 1.5″ schedule 40. The upper hanger plate 54 is welded onto the mild steel tubing 52. Holes 56 are drilled in locations that correspond to the predrilled holes 20 in the frame's mild steel tubing 12. The upper portion of the entire hanger assembly 50 varies per application and structure. Please see
The lower portion 58 of the hanger plate assembly 50 is a steel plate that is drilled to correspond to the bolt holes 20 for the frame and the upper hanger plate 54 of the hanger assembly 50. These parts are often painted or powder coated, often flat black, so that is not visually intrusive to the general public and so that it matches the frame.
A side version of a hanger assembly 50′ is illustrated in
The entire assembly is erected on site and is bolted together using grade 5, ½″ times 13″ Carbon Zinc Plated Hex Head Bolt 60, with a ½ Carbon Zinc Plated Nylok nut 62, and flat ½ washers 64.
The pipe clamps 72 are measured out to fit the support hangers. Likewise, the outrigger pipe 80 is sized to fit common lighting fixtures with ease.
All of the parts of the wire rope tension grid system are design for modular installation, easy and safe use, and simple maintenance.
Number | Name | Date | Kind |
---|---|---|---|
265551 | Wickersham | Oct 1882 | A |
448101 | Whittier | Mar 1891 | A |
867178 | Wiley | Sep 1907 | A |
896213 | Kerpoot | Aug 1908 | A |
2076810 | Deckard | Apr 1937 | A |
2326052 | Moore | Aug 1943 | A |
2709626 | Woodburn | May 1955 | A |
3021114 | O'Connell | Feb 1962 | A |
3434567 | Wilkins | Mar 1969 | A |
4068855 | Hackett | Jan 1978 | A |
4129197 | Preston | Dec 1978 | A |
4388982 | Yonahara | Jun 1983 | A |
4401186 | Dobersch | Aug 1983 | A |
4433700 | Dohet | Feb 1984 | A |
4449843 | Wendel | May 1984 | A |
4492364 | Boyanton | Jan 1985 | A |
4981225 | Cole | Jan 1991 | A |
5165207 | Oehlke | Nov 1992 | A |
5203428 | Beeche | Apr 1993 | A |
5402988 | Eisele | Apr 1995 | A |
5543196 | Robinson et al. | Aug 1996 | A |
5573125 | Denny | Nov 1996 | A |
5649690 | Kilmer | Jul 1997 | A |
5711400 | Tan | Jan 1998 | A |
5787955 | Dargie | Aug 1998 | A |
5797641 | Lincoln | Aug 1998 | A |
5799752 | Perry | Sep 1998 | A |
5984121 | Cole | Nov 1999 | A |
6006923 | Helmy et al. | Dec 1999 | A |
6026545 | Duggan | Feb 2000 | A |
6164476 | Rene et al. | Dec 2000 | A |
6182790 | Denny et al. | Feb 2001 | B1 |
6186274 | Reynolds et al. | Feb 2001 | B1 |
6536167 | Glavan | Mar 2003 | B2 |
6561107 | Wood et al. | May 2003 | B1 |
6722512 | Scully | Apr 2004 | B2 |
6837388 | Calleja | Jan 2005 | B2 |
6851661 | Penning | Feb 2005 | B1 |
7014053 | Calleja | Mar 2006 | B2 |
7191907 | Conway | Mar 2007 | B2 |
7389856 | Irvin | Jun 2008 | B2 |
7735606 | Norton | Jun 2010 | B1 |
7740048 | Wilson | Jun 2010 | B2 |
7954656 | Cuzzocrea | Jun 2011 | B1 |
8123001 | Apostolopoulos et al. | Feb 2012 | B1 |
20020020584 | Cjepa | Feb 2002 | A1 |
20020029932 | Apostolopoulos | Mar 2002 | A1 |
20020104710 | Thompson et al. | Aug 2002 | A1 |
20020144469 | Glavan | Oct 2002 | A1 |
20030001424 | Mundell et al. | Jan 2003 | A1 |
20030131539 | Burford et al. | Jul 2003 | A1 |
20030145799 | Hays et al. | Aug 2003 | A1 |
20030177705 | Forbis et al. | Sep 2003 | A1 |
20040079586 | Walls et al. | Apr 2004 | A1 |
20040117928 | Apostolopoulos | Jun 2004 | A1 |
20040245512 | Naegele | Dec 2004 | A1 |
20060201744 | Curtis et al. | Sep 2006 | A1 |
20080251322 | Irvin | Oct 2008 | A1 |
20100018802 | Sani | Jan 2010 | A1 |
20110204760 | Finstad et al. | Aug 2011 | A1 |
Number | Date | Country |
---|---|---|
549359 | Jun 1993 | EP |
WO 9501495 | Jan 1995 | WO |
Entry |
---|
Modern Language Association (MLA): “angle.” Dictionary.com Unabridged. Random House, Inc. Aug. 21, 2013. <Dictionary.com http://dictionary.reference.com/browse/angle>. |
Number | Date | Country | |
---|---|---|---|
20080190044 A1 | Aug 2008 | US |