BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to evacuation chutes, and more particularly to an evacuation chute having a bracket suitable for mounting on a building or an aerial ladder, and which is usable at any height up to the full length of the chute.

2. Description of the Prior Art

Chutes to enable persons to escape from multi-story buildings are known in the art.

Tracy, U.S. Patent No. 4,099,595 shows an escape chute having a frame mountable on a window edge or on a cherry picker. Elastic bands are provided for cushioning the descent of a person passing through the chute, and a mechanism is provided for retracting the chute.

Curiel, U.S. Patent No. 4,778,031 discloses an escape chute having inner and outer chutes to provide additional heat protection. The inner chute includes an elastic band to slow the rate of descent through the chute.

Leisman, U.S. Patent No. 4,681,186 discloses a tubular escape chute having a zipper running lengthwise along the tube to allow entry into or exit from the chute at different elevations. The chute may have inner and outer chutes, and may include elastic in the inner chute to slow the rate of descent.

Tracy, U.S. Patent No. 4,339,019 discloses a foldable emergency chute which is raised and lowered on a crane apparatus.

Other examples of safety chutes are shown in, for example, U.S. Patent Nos. 4,398,621, 4,595,074, 22,324, 3,027,996, 179,525, 27,992, 113,958, 132,073, 3,910,377.

None of these references provide a rescue chute which is adaptable for securing a rescue chute to a fixed structure, such as a building wall, and to an aerial ladder. Furthermore, none of these references disclose a rescue chute for attachment to an aerial ladder which is adjustable to level the chute at varying angles, and which is suitable for easy installation and removal. Nor do these documents disclose a chute suitable for being secured to a catwalk or other structure having an upper and lower railing.

SUMMARY OF THE INVENTION

The rescue chute of the present invention is a versatile escape device intended for use by fire and other emergency professionals. It functions as a uniquely fast and safe method of evacuating elevated structures under emergency conditions. It is especially useful for removing disabled, elderly and unconscious people. The rescue chute is suitable for attachment to either a building wall or window sill, or to a fire rescue ladder.

The rescue chute includes two concentric tube-shaped fabric chutes supported by a unique multi-purpose mounting bracket. The outer chute is made of a heat-resistant material such as Gentex® and protects the inner chute and escaping people from heat and flames. The rescue chute may be used to lengths of more than 200 feet.

To stabilize the chute, the outer chute is equipped with guying rings at intervals along its length. At the mounting point for the guying rings.

the outer chute material is reinforced with laminated nylon material.

The outer chute is equipped with snap hook- and-ring closures at intervals along its length. These ensure that the outer chute encloses the inner chute except at the point at which the chute reaches the ground, at which point the outer chute will be opened to allow people to escape. This allows the present rescue chute to be used to evacuate persons from any height up to the maximum length of the chute. The vertical edges of the outer and inner chutes may be reinforced with nylon webbing.

The inner chute is preferably made of fire retardant coated Cordura® which provides excellent heat resistance, high tensile strength and durability.

The inner chute has a zipper running the entire length of the chute. Zipper-stops and zipper- pulls are placed on the zipper at 7-foot intervals to allow the inner chute to be opened at the appropriate point to allow people to exit the chute at ground level. A snap hook is located at the end of each zipper to ensure that each zipper remains closed as the chute is used.

An elastic panel running the entire length of the chute is provided to allow the inner chute to expand to accommodate larger and smaller users and to assist in moderating the user's rate of descent to a safe speed. In one embodiment, the Spandex® elastic is sandwiched between two sheets of Cordura® to protect it from the heat. The combination of an outer chute of Gentex®, an inner chute of fire retardant coated Cordura® and an air gap between them provides exceptional heat protection.

If desired, the outer chute may be constructed of an elastic material. The inner spandex panel may be eliminated since adequate speed regulation is provided by the outer elastic chute. In this embodiment, the inner chute is preferably made of Trevira® and Kevlar®, and the outer chute is preferably made of Trevira® and an elastic material.

A non-abrasive entry flap is provided to reduce fear by restricting the length of the inner chute which is visible through the entry point, and to protect both the user and chute.

A multi-purpose bracket is adaptable to support the rescue chute on a fixed structure, such as a building wall, or on an aerial ladder. The bracket is made of coated tubular aluminum and is lightweight. It allows the chute to be installed and removed very quickly without the use of special tools. The multi-purpose bracket is square-shaped and includes elastic bumpers to support the chute against a building in an aerial ladder configuration.

The present invention includes an adjustable clamp for securing the rescue chute to a window sill or balcony. Two screws having knurled handles are threadably inserted into the bracket. As the knurled tightening knobs are rotated, they apply pressure against a clamp bar which applies pressure to downwardly extending clamping blocks. In conjunction with downwardly extending clamping supports, the supporting wall is squeezed between the clamping supports and the clamping blocks to support the rescue chute.

The multi-purpose bracket is also suitable for use on a variable-angle aerial ladder. Clamp arms are provided for grasping a rung of the aerial ladder at one end, and being fixedly attached to the

rescue chute at the other end. These allow the bracket to be attached to an aerial ladder quickly and securely. To compensate for the angle of the aerial ladder, a leveling arm attaches as a third connecting point between the aerial ladder and the multi-purpose bracket. A metal spoked adjusting wheel allows the rescue chute to be leveled through the range of angles possible for the aerial ladder.

The clamp arms and leveling arm include hook clamping members for grasping a rung of the ladder. The hook clamping members have C-shaped locking members to close around the rung. A locking pin secures the clamping member to the rung. The locking pin includes a resilient member to prevent the pin from falling out of the clamp.

The inner and outer chutes are securely attached to the multi-purpose bracket, by means of grommets, reinforced nylon webbing, bolts, and an aluminum strip. These give the chutes excellent support, and reduce the likelihood of a chute tearing.

An alternative bracket is suitable for attachment to a catwalk, or other platform having upper and lower railings. The frame is provided with an adjustable-length extension arm and jaw clamp for grasping an upper railing, and a downwardly extending adjustable-length lower extension arm having a jaw clamp for grasping a lower railing.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a perspective view of the mounting bracket and rescue chute of the present invention.

FIG. 2 shows a cross-sectional view of the support mechanism of the rescue chute along Section 2-2.

FIG. 3 shows a partial cutaway perspective view through Section 3-3 of the inner and outer chutes of the rescue chute of the present invention.

FIG. 4 shows a top view of the support bracket of the rescue chute of the present invention.

FIG. 5 shows a side view of the support bracket of the rescue chute of the present invention.

FIG. 6 shows a rear view of the support bracket of the rescue chute of the present invention.

FIG. 7 shows a perspective view of the rescue chute of the present invention mounted on a rescue ladder.

FIG. 8 shows a cross-sectional side view through Section 8-8 of the support bracket of the rescue chute of the present invention mounted on a rescue ladder.

FIG. 9 is a perspective view of the leveling arm for the support bracket of the rescue chute of the present invention.

FIG. 10 shows an embodiment of the inner chute of the rescue chute of the present invention.

FIG. 11 is a perspective view of a bracket for securing the rescue chute to a catwalk railing.

FIG. 12 is a cross-sectional view through Section 12-12.

FIG. 13 is a preferred weaving pattern for an elastic outer chute.

FIG. 14 is a perspective view of a bracket for securing the rescue chute to a wall.

FIG. 15 is an exploded view of the securing means for tightening the bracket shown in FIG. 14 against a wall.

DESCRIPTION OF THE PREFERRED EMBODIMENT

As shown in FIGS. 1 and 3, the present invention is a rescue chute suitable for attachment

to either a building wall or window sill, or to a fire rescue ladder. The rescue chute includes two concentric tube-shaped fabric chutes, outer chute 2 and inner chute 4, supported by mounting bracket 6.

The outer chute 2 is preferably made of a heat-resistant material such as Gentex®. Outer chute 2 protects inner chute 4 and users of the chute from radiant and convected heat. It also provides some protection from smoke, water and other elements.

The present rescue chute may be used to lengths of more than 200 feet. To prevent motion of the chute in windy conditions, or to help stabilize the chute while in use, outer chute 2 is preferably equipped with guying rings 8 located along its sides at intervals along its length. Each guying ring 8 includes a D-shaped link 10 to serve as an attaching point for a rope or other securing means, and a fabric base 12 to secure the D-shaped link 10 to the outer chute 2. At the mounting point on outer chute 2 for the guying ring base 12, the outer chute material is preferably reinforced with a patch of high strength nylon material laminated to the outer chute 8. If desired, a reinforcing patch may be mounted on both the inside and outside of outer chute 2 at the attachment point. The base 12 for guying ring 8 is then preferably sewed to the outer chute 2.

The outer chute 2 is also preferably equipped with snap hook-and-ring closures 14 at intervals along its length. These function to ensure that the outer chute encloses the inner chute except at the point at which the chute reaches the ground. The closures 14 are preferably mounted at 30 inch intervals along the length of outer chute 2. At the point at which the chute reaches the ground, people may be allowed to exit the chute by releasing hook-

and-ring closure 14 at that point to open outer chute 2, and opening inner chute 4 at the same point, as described below. This allows the rescue chute to be used to evacuate persons from any height up to the maximum length of the chute. Snap hook-and-ring closures 14 are preferably conventionally sewed to outer chute 2. Outer chute 2 may be reinforced at the attachment points for snap hook-and-ring closures 14 with laminated nylon, as previously described. Snap hook-and-ring closures 14 are positioned on outer chute 2 so as to allow an area of overlap 22 of the outer chute, preferably 10 inches.

In a preferred embodiment, the vertical edges 16 of outer chute 2 are preferably reinforced. This is done by first folding the edge of the material a small distance, preferably less than an inch, inward along the entire length of the edge. A nylon strip, preferably 2 inches wide, is then preferably folded around the edge and sewed into place. This method has been found to provide added strength to the vertical edges 16 of outer chute 2, and helps to improve durability of the chute. It is readily foreseen that other methods of strengthening the edges may be used.

Inner chute 4 is equipped with a zipper 18 running the entire length of the chute. Zipper 18 is preferably conventionally sewed to the vertical edges of inner chute 4. If desired, the edge of zipper 18 may be rolled with the edges of inner chute 4 and reinforced with nylon webbing before being sewed to add extra strength to the seam.

Zipper-stops and zipper-pulls are preferably placed on the zipper 18 at 7-foot intervals. These allow 7-foot sections of the inner chute 4 to be opened individually as necessary. For

example, if a 200 foot chute is in use, and people are being evacuated from a height of 100 feet, the inner chute zipper 18, and the outer chute snap hook- and-ring closure 14 may be opened at the appropriate point to allow people to exit the chute at ground level. A snap hook 20 is located at the end of each zipper to ensure that each zipper remains closed as the chute is used.

Zipper 18 preferably has nylon-coated metal teeth and polyester taping. It is readily foreseen that any conventional zipper or other fastener may be used to close inner chute 4.

Both inner chute 4 and outer chute 2 are preferably open at their bottoms. It is foreseen that all seams and edges of the chute may be reinforced with nylon webbing, if desired.

The inner and outer chute are preferably concentric throughout their lengths, with an air gap between them. An elastic panel 24 is provided to allow the inner chute 4 to expand as necessary, both to accommodate larger and smaller users and to assist in moderating the user's rate of descent to a safe speed. Elastic panel 24 preferably runs the entire length of the inner chute. It is attached to the inner chute 4 so that it gathers the inner chute into a pleat.

As shown in FIG. 10, in one embodiment, the inner chute is constructed of 4 sheets of Cordura® 100-103 and a strip of Spandex® elastic 104. The edges of the Spandex® are preferably sewed lengthwise onto one of the sheets of Cordura® 101 several inches in from the edges of the Cordura® sheet. This forms the Cordura® into a pleat 105. The vertical edges of a second sheet of Cordura® 100 are then sewed to the edges of the first sheet 101, sandwiching the

Spandex® 104 to protect it from heat. The two sheets of Cordura® 100 and 101 are sewed at their edges after having their edges rolled and reinforced by a 2 inch strip of nylon webbing, as previously described. This sandwiched Spandex® panel forms elastic panel 24.

Each vertical edge of elastic panel 24 is sewed to an edge of the 2 remaining Cordura® sheets 102 and 103. Each free edge of the remaining Cordura® sheets is sewed to an edge of zipper 18 to complete the inner chute 4. All of the seams may be rolled and bound with reinforcing material before being sewed, if desired.

In an alternative embodiment, as shown in FIG. 3, a continuous sheet of Cordura® may be used to form the inner chute 4. In this embodiment, the Spandex® is just sewed into the Cordura to make a pleat, thereby forming elastic panel 24.

The unique combination of chute materials functions to provide an additional degree of heat resistance beyond those of the materials themselves. Using an outer chute of Gentex®, and an inner chute of Spandex® and fire retardant coated Cordura®, it has been found that the thermodynamic characteristics of the combination are such that when the outer chute is subjected to an external temperature of 1,800° F, the temperature within the chute rises by only 6°F.

A non-abrasive flap 26 made of heat-treated woven nylon is provided at the entrance to the chute. The function of the non-abrasive flap 26 is threefold. First, it protects the users from being injured by contact with the hardware used to attach the chutes. Second, it protects the inner chute from abrasion at the entry point. Third, it reduces users' fear by restricting the length of the inner

chute which is visible through the entry point. Non- abrasive flap 26 preferably includes panels of Spandex® to bias the flap inward to obscure visibility down the chute. Non-abrasive flap 26 preferably extends only a few feet down the chute.

If desired, the chute may also include an entry canopy. As people are entering the chute at a high elevation, they would ordinarily be able to see around the chute to the ground and the surroundings. A canopy frame is preferably mounted on and above bracket 6. The canopy frame secures a fabric canopy around the chute opening, and limits visibility while entering the chute. A dividing entry curtain is opened to allow people to enter the chute.

As people are being evacuated through the chute, it has been found that some are apprehensive because they do not know when they are about to reach the ground. If desired, tactile safety warning means may be provided inside the inner chute to inform evacuees of their present location. For example, one or more Velcro® or other abrasive strips may be installed circumferentially inside the chute 10 or 15 feet above the exit of the chute. Evacuees will feel the Velcro®, or other abrasive fabric, and be aware of their location. It is foreseen that other less practical safety warnings, such as an audible warning, are possible.

In an alternative embodiment, each of the inner and outer chutes is circular with no spandex panel present on the inner chute. The inner chute is a weaved material with 400 denier Dupont® Kevlar® as the warp yarn, and 14/2 Trevira® Polyester Type 271 as the fill yarn. A preferred weave pattern is shown in FIG. 13. The inner chute has a diameter suitable

for a person to be evacuated on a rescue litter or board.

The necessary elasticity to regulate the speed of a person moving through the inner chute is provided by the outer chute. The outer chute preferably comprises a knit of 70-75% 24/1 Trevira® Type 272 polyester, and 25-30% 1/700 Type S-7 Glospan®. While the outer chute has a smaller diameter than the inner chute, the Glospan® provides sufficient elasticity to the outer chute so that it will stretch to enable a person to move downwardly while regulating their speed. The actual diameter of the outer chute will depend upon the elasticity of the outer chute material.

While this embodiment is not preferred for fire applications since the outer chute is not fire¬ proof, it is preferred as escape means in non-fire applications, i.e. for escaping from a catwalk in an industrial accident, etc. These chutes are also easier to use if there is no attendant to secure the bottom of the chute. Finally, the chutes may be sized to enable a rescue litter to be passed therethrough. For fire applications, these chutes may be combined with a Gentex® chute as discussed above. If desired, the chutes may be sewed together lengthwise at a point around the circumference of the chutes, and a single zipper oriented lengthwise may be used to exit from both chutes.

A multi-purpose bracket 6 is provided which is adaptable to support the present rescue chute on a fixed structure, such as a building wall, or on an aerial ladder. Multi-purpose bracket 6 is preferably made of tubular aluminum which functions to support the chute securely in a wide variety of situations, and is relatively lightweight. It also functions to

allow the chute to be installed and removed very quickly without the use of special tools.

As shown in FIG. 4, multi-purpose bracket 6 includes four tubular member 30 which are fixedly attached at their ends to form a square-shaped support for the rescue chute. Butting the ends of two of the tubular members 30 are elastic bumpers 32. These are preferably made of rubber or other elastic material. When the rescue chute is being used on an aerial ladder, these allow the chute to be butted against a building, thereby making the rescue chute significantly more stable in use.

As shown in FIGS. 4-6, multi-purpose bracket 6 may be configured to mount the present rescue chute on a fixed-position structure such a window sill or balcony. Two screws 34 are threadably insertable in two of the tubular arms 30. Screws 34 are preferably made of stainless steel and have knurled tightening knobs 36 on one end, the other end being screwed into tubular arms 30. Knurled tightening knobs 30 allow the clamp to be tightened quickly and securely without the aid of additional tools. As knurled tightening knobs 30 are rotated, they apply pressure against clamp bar 38 which applies pressure to downwardly extending clamping blocks 40. Clamping blocks 40 preferably include urethane pads 42 which butt the wall which will support the chute.

On the other side of the support wall, reinforced downwardly extending clamping supports 44 are provided. These are reinforced by reinforcement bars 46. As knurled knobs 30 are tightened, the supporting wall is squeezed between clamping supports 44 and clamping blocks 40. When knurled knobs 30 are loosened, the rescue chute is released from the wall.

As shown in FIGS. 7-9, multi-purpose bracket 6 is also suitable for use on a variable- angle aerial ladder. Clamp arms 48 are provided for grasping a rung of the aerial ladder at one end, and being fixedly attached to clamp bar 38 at the other end. These function to allow the bracket to be attached to aerial ladders quickly and securely. Each clamp arm 48 includes a base member 68 which is attached to clamp bar 38 such as by stainless steel screws.

To compensate for the angle of the aerial ladder, leveling arm 50 attaches as a third connecting point between the aerial ladder and multi¬ purpose bracket 6. The leveling arm 50 attaches between the horizontal support rung 48 of the multi¬ purpose mounting bracket 6 and a rung of the aerial ladder.

Each of the clamp arms 48 and leveling arm 50 includes a hook clamping member 58 for grasping a rung of the ladder. Each hook clamping member 58 includes C-shaped locking member 60 and lock base 62. On each clamp arm 48, clamp base 68 preferably is integral with lock base 62. In use, a rung is inserted into the clamp, and C-shaped locking member 60 is closed around the rung. A locking pin is preferably then inserted through hole 64 to securely lock the clamping member 58 to the rung. The locking pins ensure that the clamps cannot release unexpectedly while still allowing the clamps to be released quickly when desired. The locking pin includes a resilient member to prevent the pin from falling out of hole 64 while the clamping member is in use. This resilient member is preferably a spring biased ball recessed in the locking pin.

As shown in FIG. 9, leveling arm 50 includes short base 66 and long base 56, preferably constructed of aluminum. Each of these bases 56 and 66 preferably are integral with the lock base 62 of their respective C-clamps. Each base 56 and 66 is preferably drilled out to form a hole to allow threaded adjusting post 54 to be freely movable therein. After threaded adjusting post 54 has been inserted in each hole, the ends of the holes are capped to allow free movement of threaded adjusting post 54 in the hole, but to prevent threaded adjusting post 54 from being removed from the hole.

A metal spoked adjusting wheel 52 is provided for varying the effective length of leveling arm 50 and thus functions to level the multi-purpose bracket 6 through the range of angles possible for an aerial ladder. By allowing free movement of adjusting post 54 in the hole of long base 56, the chute may be quickly adjusted to the proper angle. The bracket is lifted by a fireman to the correct angle, and then metal spoked adjusting wheel 52 is spun to the correct position to support the bracket.

It is foreseen that adjusting post 54 may be threaded into long base 56 and that adjusting wheel 52 may be fixed to post 54 to provide the same leveling function as described. However, the preferred embodiment described above allows the rescue chute to be deployed and stowed faster than previously possible.

Multi-purpose bracket 6 and support arms 48 and 50 are preferably constructed of coated aluminum. The attachment hardware, i.e. bolts, nuts, and adjusting post 54 are preferably made of stainless steel. It is foreseen that other high strength, lightweight, water-resistant, and corrosion-resistant

materials may be used in the various parts of the present invention.

As shown in FIGS. 1 and 2, the fabric chutes 2 and 4, and non-abrasive flap 26 are securely attached to the load-bearing tubular members 30 of multi-purpose bracket 6. As shown in FIG. 2, the inner and outer chutes 2 and 4 may be brought over the tubular members 30 and back down to a point at which the top edges of the chutes are brought into contact with the inner chute. This occurs preferably 6 inches down form the top of tubular members 30. At the points of contact, i.e. the top edges of each chute, and the point 12 inches down each chute, the chute material is preferably laminated on each side with a reinforcing nylon webbing. Grommets are then inserted through the each layer of chute and reinforcing nylon. Since the outer chute 2 is wider than the inner chute 4, the outer chute 2 will preferably be supported by 5 bolts, so the outer chute 2 will have 5 grommet holes located 12 inches down, and 5 grommet holes near the top edge. These grommet holes preferably line up when the outer chute 2 is brought down over tubular members 30.

Inner chute 4 preferably has 3 grommet holes near its top edge and 3 aligned grommet holes at about 12 inches down form the top edge. These 3 holes preferably line up with the 3 center holes of the 5 holes in the outer chute 2. A strip of reinforcing aluminum is preferably placed between the two layers of chutes at their connection point to add strength. The reinforcing aluminum strip preferably has pre-drilled holes aligned with the holes in the chutes. Five conventional bolts 70 and nuts 68 on each side are preferably used to secure the chutes to the tubular members 30.

As shown in FIG. 2, two strips of aluminum 72 may also be used to sandwich the layers of chutes, if desired. Also as shown in FIG. 2, non-abrasive flap 26 may be reinforced at its top edge with laminated nylon reinforcement, and have grommets installed, and be secured to tubular members 26 along with the chutes. It is foreseen that the present invention may be configured with a multi-purpose bracket that is not necessarily square-shaped, although a square or rectangular shape has been found to be the most advantageous.

Using an alternative bracket 200, as shown in FIGS. 11-12, the rescue chute may be attached to the rails of a catwalk or the like having upper and lower rails 224 and 226. Railing bracket 200 includes an upper, generally rectangular member 202 and lower members 210. Lower members 210 are attached to upper member 202 at hinge 208. The railing bracket 200 is preferably constructed of tubular stainless steel.

The rescue chute is secured to the rectangular portion of upper member 202 as described above. Upper support arms 204 are slidable in the open-ended extensions 230 of upper member 202. Likewise, lower support arms 214 are slidable into and out of lower members 210. Upper and lower support arms 204 and 214 each include holes 222 spaced lengthwise along the arms, and extending therethrough. Each of the members 202 and 210 include a hole through which pins 206 and 212 are inserted to lock the support arms into position, and which may be removed for adjusting the length of the arms. Each of the support arms 204 and 214 includes a clamping member 216 for locking the bracket 200 onto the railing members 224 and 226. One of the

jaws of each clamp 216 is rigidly secured to its respective arm 204 and 214. The other jaw is hinged to the fixed jaw and extends around the railing and is locked to the railing by removable locking pin 218. The upper and lower portions of the bracket 200 may be independently adjusted for securing the bracket to different types of railings at different orientations.

Another bracket for securing the rescue chute to a wall is shown in FIGS. 14 and 15. This bracket 250 is similar to that discussed with respect to FIGS. 11 and 12, and includes an upper, generally rectangular member 202 and lower members 210. Lower members 210 are attached to upper member 202 at a hinge. Lower members 210 are attached at their bottoms by an outer wall brace member 264. Outer wall brace member contacts the outside of the wall 270 for supporting the bracket 250. Friction pads 272 or the like may be provided for improving the strength of the wall-outer wall brace member 264 interface.

Upper support arms 204 are slidable in the open-ended extensions 230 of upper member 202. Upper support arms 204 and member 202 include locking holes for a locking pin 206, as discussed above. Support arms 204 are connected to downwardly extending brace members 260, which are connected by inner wall brace member 262 at their bottoms.

At each end of inner wall brace member 262 a tightening mechanism 252 is provided, as shown in FIG. 15. A screw 254 is threaded through inner wall brace member 262 and is connected to a support plate 256. By turning the screw 254, support plate 256 is made to butt up against the wall for tightening the bracket around the wall. In practice, the pin

adjusting mechanism is used to fit the bracket around the wall, and the tightening mechanism is used to tighten the bracket to the wall.

In order to prevent the outer wall brace 264 from moving downward and away from the wall, a support strap is connected between the inner wall brace member 262 and the outer wall brace member 264. The strap is tightened by means of a buckle or ratcheting member 278. To use the bracket, the pin adjustment mechanism is used to place the bracket around the wall. Then, the outer wall brace member is lifted and locked against the wall by means of the strap mechanism. Finally, the screw tightening mechanism is used to tighten the bracket to the wall.

Although the present invention has been described in detail with respect to certain embodiments and examples, variations and modifications exist which are within the scope of the present invention as defined in the following claims.