Spring force safety locking system for sectional doors

Information

  • Patent Grant
  • 6742564
  • Patent Number
    6,742,564
  • Date Filed
    Friday, June 7, 2002
    22 years ago
  • Date Issued
    Tuesday, June 1, 2004
    20 years ago
Abstract
Hardware that improves safety and minimizes the risk involved in installing, maintaining, and operating sectional doors that use springs to facilitate door movement. A lock-on side bearing bracket bears up a spring on a garage door. This side-bearing bracket includes a hook and a perpendicular tab to prevent the spring from dangerously releasing its energy when parts supporting the spring are removed or fail. A lock-on bottom roller bracket having a bottom bearing plate and a safety hook similarly prevents a potential release of energy when the garage door lift cable is tensed. A curled portion at the bottom of the lift cable prevents the cable from coming off the drum. A safety latch with a latch bar and a latch cover acts as a lock for the garage door.
Description




BACKGROUND




1. Field of the Invention




The present invention relates generally to the field of sectional doors and related safety devices. More particularly, the present invention relates to novel hardware devices designed to improve safety and minimize the risk involved in installing, maintaining and operating sectional doors which utilize spring mechanisms to facilitate door movement.




2. Background




Large doorways in garages, shops, stores, warehouses and other buildings often use sectional doors to enclose the doorway opening. These doors are generally constructed of wood or metal panels which are joined by metal hinges and hung from metal rollers which travel along a fixed track at each side of the door. Sectional doors typically range in size from small storage unit models of just a few feet wide to very large models which accommodate trucks and heavy equipment. Sectional doors are used for residential garages where they are found in one and two car sizes.




The size of sectional doors and the weight of their materials make them relatively heavy and, therefore, difficult to lift. Many doors also contain insulation and other materials which further add to the door's weight. Even an average-sized residential garage door can weigh several hundred pounds, making it impossible for the average person to lift.




As a consequence of the weight of sectional doors, mechanisms have been invented to counteract the door's weight thereby allowing manual operation of the door. One common method of counteracting a door's weight is accomplished with a counterspring mechanism using springs which are displaced elastically as the door is shut, thereby exerting a lifting force on the door as it is closed. This spring force slows the fall of the door during closing and aids significantly in lifting the door; in effect, the door weight is balanced.




Coil springs, in a torsion spring configuration, are often used for these mechanisms. In a torsion spring configuration, the coil spring is deflected or wound around the axis of its helix. In a typical coil spring configuration, as shown in

FIG. 1

, one or more coil springs


2


are wound around a shaft


4


near the top of the door


6


. One end of each coil spring


2


is attached to a mounting bracket


8


which is connected by screws


12


to the building structure which is typically a wooden beam


14


across the door opening. The other end of the spring is attached to a cable drum pulley


16


around which a cable


18


is wound. The cable


18


extends to the bottom of the door where it is attached with a bracket


20


. These coil springs are pre-wound or pre-tensioned to increase lifting potential and ensure that the door is lifted to a fully opened position.




As the door closes, the cable unwinds from the cable drum pulley thereby twisting the spring and increasing the torsion on the spring and the energy stored within the spring. A properly adjusted spring mechanism will exert a force on a door that is about the same as the weight of the door allowing a user to open the door with the slightest of lifting effort. This means that the ideal spring mechanism, on an average door, will need to store an amount of energy that is approximately equal to the weight of the door. In terms of force and considering the lever arm of the cable drum, the spring holds a force of at least twice the weight of the door. Consequently, these spring mechanisms store a great deal of energy that is unleashed as a twisting force. Under proper operating conditions, this mechanism results in a smoothly operating door, but when poorly or improperly maintained or installed this force can be instantly unleashed in an injurious and even deadly fury.




One problem area where serious injuries can occur is at the location where the spring mounting bracket


8


attaches to the building. The spring mounting bracket is usually attached to a wood header or beam spanning across the doorway opening or vertical wood stud members.




These beams, headers or studs are typically wood members that sometimes have a relatively high moisture content at the time of construction. Over time the wood loses its natural moisture, causing shrinkage, warping or bowing of the framing members as the shrinkage pattern encounters natural inconsistencies in the grain of the wood. Cracking also results from this natural moisture loss leaving large voids in what was once solid lumber. As a result of this drying process, holes drilled for screws and mounting hardware may expand, crack and otherwise deform leaving the screws or other connectors loose and structurally weakened.




The connection to the wood support is typically made with lag screws which penetrate holes in the bracket and thread into drilled holes in the wood. This type of connection generally appears structurally sound over the short term, but problems may arise with wood shrinkage and installation problems. As the wood shrinks, the screw holes expand and the grip on the screw threads decreases and fails. Problems may also arise from installation error or misjudgment. Holes for lag screws should be drilled to an exact size to provide optimal screw capacity. When holes are over-bored to a diameter that is larger than the optimal size for the screw, the screw's holding capacity is greatly diminished. Similarly, a hole may be drilled too small or not at all which may cause the wood to crack when the lag screw is installed or a screw is inserted. Likewise, a lag screw or other fastener maybe over-tightened, causing the screw thread to twist within the hole, thereby removing some of the wood material within the hole and effectively stripping the hole interior. This also weakens the screw's holding capacity.




Often, siding material is applied to the interior face of the doorway structure to which the spring mounting bracket is attached. Generally, this siding is a gypsum-based “drywall” or “sheetrock” material that provides fire-proofing and aesthetic benefits but has very little structural strength. Screws and other fasteners which must penetrate this layer have considerably lower holding capacity due to the decreased fastener penetration into the sound structural wood below. Sometimes a piece of 2×4 or 2×6 is nailed through the sheetrock to the structure below, to which the spring mounting brackets are fastened. In this situation, the spring's torsional force is now contained only by the nails.




The problem is exacerbated by the repetitive vibration the connection must endure. The vibration and stress caused by the repeated opening and closing of the door, especially when performed by high-speed electric openers, can be an additional and significant factor in connection failure. Screw connections that are already weakened by the above-mentioned factors can vibrate loose and screws can even wiggle right out of their holes.




When the mounting bracket connection fails, the entirety of the stored torsional energy of the door spring is instantaneously unleashed, typically through uncontrolled, high-velocity spinning of the sharp-edged metal mounting bracket. When this failure occurs, any person or thing in close proximity to the bracket will be injured or destroyed. The energy of the spring mechanism is sufficient to cause severe injury and can easily maim, dismember or kill a person who is near the unit at the time of failure.




A dangerous situation often presents itself when an unwary homeowner or repairman observes loose or missing fasteners on the spring mounting bracket. Generally, the observer's reaction is to tighten the loose fasteners. This typically requires the “repairman” to climb a ladder, putting himself in very close proximity to the spring mounting bracket while tightening the loose fastener with a wrench. If the holes have expanded due to drying or have been stripped out or otherwise weakened, the attempted “tightening” will generally cause further weakening of the connection which is under spring force load often causing complete connector failure. When complete connector failure occurs, the spring force is instantly released by the wildly spinning mounting bracket immediately adjacent to the unwary, surprised and potentially badly injured “repairman.”




Another safety problem occurs at the location where the cable


18


attaches to the door. This connection is typically made with a bracket


20


which is attached to the door with sheet metal screws. Like the rest of the spring mechanism, an enormous amount of energy is stored in the connection between the cable and the door. While this connection is not as prone to failure from wood deterioration or installer error, it can fail as a consequence of fatigue, improper installation, collision damage or corrosion. Common sheet metal screws are typically installed with power tools which can over-tighten and strip the metal parts they connect, leaving a weakened connection. Fatigue due to repeated stress cycles as the door opens and closes also takes a toll on the connection, especially with light gauge materials. Even when the connection is not seriously compromised, for example, in a light collision which slightly bends or breaks a bracket, an observer will have a desire to replace the damaged part, thereby exposing himself to danger. Most commonly, this danger presents itself when untrained repairmen or unsuspecting homeowners try to adjust or disconnect any part of the lift cable, bottom bracket or spring mechanism. When the majority of the cable bracket screws are removed, the lift cable can instantly fly from the door, slicing or shredding most objects in its path. Again, the full energy required to lift the heavy door around above the opening is instantly unleashed with the potential to maim or kill. Typical lift cable brackets are stamped light-gauge metal with sharp edges, further increasing the hazard.




Set screws on the spring fixtures, such as winding and stationary cones, can also be inadvertently released by a repairman or unsuspecting home owner, resulting in a similar instantaneous release of the dangerous spring energy.




SUMMARY OF THE INVENTION




The present invention reduces or eliminates the safety hazards of the prior art through the use of side mounted springs attached to lock-on side bearing brackets, tamper-resistant set screws and fasteners and lock-on bottom roller brackets which attach the lift cable to the door frame.




The problematic connection of the prior art between the mounting bracket and the building structure is eliminated by moving the coil springs to the sides of the torsion shaft above the door and attaching the springs to a bracket which is bolted to the metal track structure of the door. The track structure is screwed into the building framework, but through a much more expansive connection which avoids the concentrated, high-stress, high-torsion connection of the prior art. The preferred embodiments of the present invention incorporate multiple safety features that serve as additional safety back-ups for the systems of the present invention. Among these redundant safety features is a lock-on side bearing bracket with an inventive locking device that prevents the spring mechanism from releasing its energy even when the track and spring mechanism are entirely disconnected from the wall. Additionally, the spring mechanism energy will be retained even when the bolts holding the lock-on bearing bracket are removed. This redundant safety feature is accomplished by the use of a novel lock-on hook device which is an integral part of the bearing bracket. Many prior art side-mounted springs totally ignore safety concerns. Many of them utilize very dangerous outside lift cables which can entrap and strangle children playing with the door.




The present invention also eliminates the dangerous and problematic connection between the spring mechanism cable and the sectional door. This problem is eliminated by the use of a lock-on bottom roller bracket which is attached to the door frame with screws in a conventional manner, but which also incorporates redundant safety features. One safety feature is a lock-on bracket mechanism which hooks below the door frame, but which does not lock onto the door frame unless the attachment screws are removed or fail while tension is on the lift cable. Another safety feature is a curl located at the bottom of the lift cable which prevents the lift cable from straightening and coming off the cable drum.




The lock-on bottom roller bracket comprises a lift cable connection which uses a cable loop and clevis pin assembly. Additionally, the lock-on bottom roller bracket comprises a hook device which wraps around the bottom of the door frame and with the slightest movement prevents the bracket from being removed from the door frame while there is tension on the lift cable. The lock-on feature fastens solid only when the screws are removed while there is tension on the lift cable. The lock-on hook is designed to be free from the vertical part of the door frame unless the fasteners are removed while there is tension on the lift cable. At that point, the bottom lock-on roller bracket locks on. Further, the lock-on bottom roller bracket comprises a bottom plate which attaches below the door frame, thereby strengthening the attachment to the door and helping to prevent the bracket from instantaneously separating from the door in the case of conventional fastener failure or removal. The lock-on bottom roller bracket is designed for safer interior lift cables and may not be used as an option for dangerous outside lift cables used in some prior art designs.











BRIEF DESCRIPTION OF THE DRAWINGS




In order that the manner in which the above-recited and other advantages and objects of the invention are obtained, a more particular description of the invention briefly depicted above will be rendered by reference to a specific embodiment thereof which is illustrated in the appended drawings. With the understanding that these drawings depict only a typical embodiment of the invention and are not therefore to be considered to be limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:





FIG. 1

is a perspective view of a prior art sectional door assembly with a coil spring counter-spring apparatus.





FIG. 2

is a perspective view of the inventive sectional door counter-spring system of a specific embodiment of the present invention.





FIG. 3

is a perspective view of an inventive torsion spring assembly including a lock-on side bearing bracket of a specific embodiment of the present invention.





FIG. 4A

is a perspective view of the inventive lock-on side bearing bracket of a specific embodiment of the present invention with a horizontal track angle cut away to show the connection between the lock-on side bearing bracket and the track angle.





FIG. 4B

is a perspective view of the inventive lock-on side bearing bracket shown with alternative redundant fasteners fastened into the adjacent wall.





FIG. 5A

is a perspective view of the inventive lock-on bottom roller bracket of a preferred embodiment the present invention shown unassembled with a door frame member.





FIG. 5B

is a perspective view of the inventive lock-on bottom roller bracket of a specific embodiment of the present invention as assembled with a door frame member and cable.





FIG. 6

is a perspective view of the inventive latch with latch aperture cover in accordance with the present invention.





FIG. 7

illustrates a perspective view of the recessed securing screws for use with the drum in accordance with the present invention.





FIG. 8

illustrates a perspective view of the recessed securing screws for use with the winding cone and spring in accordance with the present invention.











DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS




The figures listed above are expressly incorporated as part of this detailed description.




It will be readily understood that the components of the present invention, as generally described and illustrated in the Figures herein, could be arranged and designed in a wide variety of different configurations. Thus, the following more detailed description of the embodiments of the system and apparatus of the present invention, as represented in

FIGS. 2 through 8

, is not intended to limit the scope of the invention as claimed, but is merely representative of the presently preferred embodiments of the invention.




The presently disclosed embodiments of the invention will be best understood by reference to the drawings, wherein like parts are designated by like numerals throughout.




The term “conventional fasteners” as used in this document refers to fasteners for connecting metal, wood, plastic and other materials common in sectional door construction. By way of example and not limitation, these fasteners comprise screws, bolts, nuts, washers, rivets, cotter pins, clevis pins, studs, threaded rods and other mechanical fasteners as well as adhesives such as epoxy, welding joints such as spot welds and conventional fillet and butt joint welds.




A non-fastener structure is a device that does not hold the items of its connection in a fixed physical relationship without other support, force or torque. A non-limiting example of a non-fastener structure is a hook, such as a hook which engages an element but only remains in contact with that element while a force acts on the hook, pulling it against the element.




A “torsion spring” or “torsional spring” is an element which is elastically deformed by a torque or rotational force and which counteracts against that torque with an equal, but opposite, torque. The torsion spring may provide the counteracting torque directly by virtue of its shape and configuration or it may counteract the torque indirectly through a mechanism which converts spring force into torque. By way of non-limiting example, a torsion spring may be a helically wound coil spring which is elastically deformed by a rotational motion about its helical axis, a torsion bar or a leaf spring connected to a lever and gear mechanism which creates torque.




The term “static structure” shall refer to any structure that is substantially static or immovable in response to the forces exerted by a typical sectional door. Examples of static structures, given by way of example and not limitation, are residential or commercial building frames including framing elements such as studs, posts, columns, beams, headers, lintels, stem walls, foundation structures and other elements that are assembled into a building frame. Other non-limiting examples of static structures are posts, fences, retaining walls and garden walls. These elements may be constructed of concrete, masonry, lumber, steel, plastic, fiberglass, aluminum or other materials.




The term “counter-spring” shall refer to any type of mechanism which uses elastic deformation of an element's shape to counteract a force or weight. By way of example and not limitation, a counter-spring may take the form of a coil spring from which an object is suspended or which stretches along its helical axis to support the weight of an object, thereby allowing the object to be lifted more easily. Also, by way of non-limiting example, a coil spring may be connected coaxially, in a torsion spring configuration, to a pulley or drum so that the spring rotates with the pulley or drum such that a cable wound around the pulley or drum from which an object is suspended would exert a counter-force against gravity, thereby allowing the object to be lifted with a force lesser than the weight of the object.




A specific embodiment of the present invention, as shown in

FIG. 2

, comprises novel safety features for use with a spring-based system of pivotally connected sectional doors. This inventive system utilizes a torsion assembly


30


which is connected by cable


40


to sectional door


50


. The roll-up door rides on rollers


52


which engage and travel within tracks


60


at each side of the door


50


. These tracks typically comprise a vertical track


62


, an arcuate track


64


, and a horizontal track


66


. Vertical track


62


is substantially parallel to door


50


when door


50


is in its closed position. Vertical track


62


is attached to wall structure


70


with a metal vertical track angle, also called a reverse angle shield


80


, and bracket material using conventional fasteners such as screws, bolts, and rivets.




Horizontal track


66


is typically attached at its end


68


to a building ceiling structure


72


using metal angle and bracket material and conventional fasteners. Horizontal track


66


is typically also attached to horizontal track angle


82


which connects with vertical track angle


80


near wall structure


70


. The horizontal track


66


, the arcuate track


64


, and the vertical track


62


are attached to the vertical track angle


80


through a connecting bracket


69


using conventional fasteners and may optionally be attached directly to the building structure. The horizontal track


66


, the arcuate track


64


, the vertical track


62


, the vertical track angle


80


, and the horizontal track angle


82


are all part of what is herein referred to as a “support track” for the sectional door


50


.




Torsion assembly


30


, as shown in FIG.


2


and in detail in

FIG. 3

, comprises a torsion shaft


31


which spans between novel lock-on side bearing brackets


84


which contain bearings


86


that support torsion shaft


31


and allow torsion shaft


31


to rotate freely. While torsion shaft


31


extends the entire width of the doorway, torsion shaft


31


may have one or more sections that are connected in a manner that will allow torque to be transmitted between each section. Torsion shaft


31


may also be supported by intermediate bearing brackets


37


which contain bearings and allow torsion shaft


31


to rotate freely within the bracket bearing. Torsion assembly


30


is generally located adjacent to the wall and immediately above the doorway as shown in

FIG. 2

, or to the rear of the horizontal track


66


as shown in FIG.


2


.




Lock-on side bearing brackets


84


may attach to horizontal track angles


82


with conventional fasteners


81


(shown in FIG.


4


A). Lock-on side bearing brackets


84


may also be attached to the wall structure


70


with conventional fasteners


83


such as lag screws. However, these conventional connections may fail due to the above described problems or may be inadvertently removed by an unwary and untrained “repairman.” Shown in

FIGS. 4A and 4B

, an inventive lock-on safety hook element


88


and a shelf or torque tab


85


on the lock-on side bearing bracket


84


prevent the lock-on side bearing brackets


84


from breaking free and spinning dangerously when the conventional fasteners are removed or fail. Note that the safety hook


88


and tab


85


are shaped to fit the contour of the adjacent horizontal track angle


82


.




Lock-on safety hook


88


hooks under horizontal track angle


82


and torque tab


85


bears on the top of horizontal track angle


82


, thereby preventing bearing bracket


84


from rotating against the hook. As door


50


closes, lift cable


40


unwinds from cable drum


36


, thereby rotating cable drum


36


which causes torsion shaft


31


to rotate, which, in turn, rotates winding cone


32


connected to spring


33


whose rotatable free end is free to rotate against the force of the spring


33


. Spring anchor cone


34


holds the fixed end of spring


33


in a static position so that rotation of spring


33


will cause increased torsional force and increased stored energy in spring


33


. As spring anchor cone


34


is attached to lock-on side bearing bracket


84


through spring anchor bracket


35


, lock-on side bearing bracket


84


must resist the full torsional force of the spring when the door


50


is closed. This torque is transmitted to the static structure of the building through lock-on side bearing bracket


84


, horizontal track angle


82


, and reverse angle shield


80


. If the conventional fasteners of the lock-on side bearing bracket are removed or fail, lock-on safety hook


88


bears up against the bottom of horizontal track angle


82


while torque tab


85


bears down on the top of horizontal track angle


82


, thereby transmitting the full torque of spring


33


into horizontal track angle


82


, which is directly and securely attached to the static structure of the building


72


, through the full length of the vertical reverse angle shield


80


. Consequently, the extremely high energy stored in the spring will not be inadvertently released and the bearing bracket will not spin dangerously upon anyone because the hook


88


and tab


85


structure will prevent this from occurring even when conventional fasteners are removed or fail.




Spring winding cone


32


circumscribes torsion shaft


31


and selectively locks against torsion shaft


31


to prevent rotation so that spring winding cone


32


maybe rotated to pre-tension spring


33


and may thereafter be locked against rotation so as to maintain the pre-tension force. In the preferred embodiment of the present invention, this rotational lock is a hardened, tamper-resistant steel set screw with a red safety warning cap. Coil spring


33


connects to winding cone


32


at the inner end of spring


33


with a torsionally rigid connection such that when winding cone


32


is rotated, torsion in spring


33


will increase or decrease depending on the direction of rotation. Spring


33


is also torsionally rigidly attached, at its outer end, to anchor cone


34


which is bolted to anchor bracket


35


which bends around cable drum


36


and attaches to lock-on side bearing bracket


84


. Once installed, the outer end of spring


33


remains rotationally fixed to anchor bracket


35


and lock-on side bearing bracket


84


because lock-on side bearing bracket is redundantly attached to horizontal track angle


82


. Cable drum


36


is torsionally rigidly attached to torsion shaft


31


. Lift cable


40


winds around cable drum


36


as torsion shaft


31


is rotated.




As shown in

FIGS. 5A and 5B

, lift cables


40


are attached, at their lower end, to door


50


, near the bottom of each side of door


50


, with lock-on bottom roller brackets


90


which attach to bottom door frame members


91


with conventional fasteners as well as with an inventive safety hook


92


of the preferred embodiment of the present invention. A bottom plate


93


further increases safety by providing a bearing surface which bears against the bottom of the door


50


, thereby decreasing stress on the conventional fasteners and providing another redundant mechanism for preventing dangerous separation of the lift cable


40


from door


50


. Lift cable


40


is attached to lock-on bottom roller bracket


90


by a cable loop


94


which receives clevis pin


95


, which, in turn, penetrates bracket


90


and is secured by cotter pin


96


.




In a preferred embodiment of the present invention, lock-on bottom roller bracket


90


comprises safety hook


92


which is configured so as to engage an element


91


of door


50


in such a way that bracket


90


will not separate from door


50


or door element


91


while lift cable


40


is tensioned. While door


50


is in a closed position, lift cable


40


is substantially vertically oriented so that cable


40


exerts a vertical force on bracket


90


, thereby pulling bracket


90


toward door member


91


, and, if fasteners are removed, engaging safety hook


92


against door element


91


. Door element


91


may be shaped with notch


97


so as to better engage hook


92


. Because of the vertical force on brackets


90


, the safety hook


92


will fully engage when there is inadvertent tampering or failure of fasteners


99


(see FIG.


2


).




A preferred embodiment of the present invention comprises bottom plate


93


on lock-on bottom roller bracket


90


. Bottom plate


93


bears on the bottom of door


50


and preferably on the bottom of door member


91


, allowing a contact area between bracket


90


and door


50


which will help prevent bracket


90


from separating from door


50


in the event that the conventional fasteners therein fail or are removed. As shown at


40


in

FIGS. 5A and 5B

, the lift cable


40


preferably has a curled portion


41


which prevents the cable from straightening and coming off the drum


36


in the event, for example, that either the left or right side of the door


50


becomes jammed or suffers an impact.




When door


50


is in an open position with its rollers


52


resting in horizontal track


66


, a substantial portion of lift cable


40


is wound around cable drum


36


and spring


33


exerts a light “pre-tensioned” torsional force on cable drum


36


which puts tension on lift cable


40


, thereby holding door


50


in the upright and open position.




As door


50


is lowered toward a closed position, lift cable


40


is pulled downward, thereby rotating cable drum


36


which is rigidly fixed to torsion shaft


31


. This action rotates torsion shaft


31


which rotates winding cone


32


which is rigidly attached to spring


33


, causing spring


33


to rotate and increase the torsional force and energy stored therein. Subsequently, as the door


50


is lifted, spring


33


is unwound, thereby releasing energy and helping lift the door


50


by counteracting the force of gravity on the door


50


.





FIG. 6

illustrates a perspective view of a safety latch


100


contemplated within the present invention. Latch


100


, which serves as a door lock on the entire door system, includes a lock support


102


, a latch bar


104


, and a latch aperture


106


, which is placed in rail


66


and can include other knockout apertures


107


as well. Lock support


102


mounts to the edge of door member


50


with either screws or bolts, or other appropriate fastening means. Latch bar


104


is part of lock support


102


and slides in a manner to engage latch aperture


106


. Latch aperture


106


further includes a latch aperture shield


108


, which is mounted in a hinged manner to support rail


66


and covers aperture


106


when latch bar


104


is disengaged. Latch aperture shield


108


prevents items from being trapped within aperture


106


during opening or closing of the door.





FIG. 7

shows a close-up perspective view of drum


34


, which mounts to rod


31


. Drum


34


includes at least one retaining screw


112


, which inserts through retaining aperture


114


. Each retaining screw


112


engages rod


31


to prevent drum


34


from rotating independently about the rod. Also, the retaining screws


112


allow drum


34


to be removably mounted to the rod for easy repairs and installation when necessary. A similar set of retaining screws


112


are used with winding cone


32


, which is illustrated in FIG.


8


. The retaining screws


112


fit through another aperture to engage with rod


31


. This allows the winding cone


32


to be secured between turns during installation. Also, it allows for the cone to be securely fixed to the rod for operation. Additionally, each screw


112


is shown to be a hex-driven screw. Accordingly, hex caps


116


can be placed within the hex opening of each screw


112


.




The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative, and not restrictive. The scope of the invention is, therefore, indicated by the appended claims, rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.



Claims
  • 1. A system comprising:a plurality of pivotally connected sectional door panels; a support track in which the plurality of sectional door panels travel between an open and a closed position; a torsion spring assembly for moving the plurality of sectional door panels between said open and closed positions, said assembly including a rotatable support shaft and a torsion spring, said torsion spring having a first end and a second end, said first end being mounted to the rotatable support shaft; a bracket coupled to said second end of the torsion spring, the bracket comprising a first surface; and a safety support extending from said bracket, the safety support being shaped to fit the contour of a portion of said support track, the safety support comprising a shelf protruding from said first surface of said bracket so that said shelf bears against said support track to prevent any tendency of the bracket to rotate with respect to the support track.
  • 2. The system of claim 1 wherein said safety support further comprises a hook that operates together with the shelf to prevent the bracket from rotating with respect to the support track, the hook wrapping around an edge of the support track.
  • 3. The system of claim 2 wherein said portion of the support track comprises a horizontal track angle and wherein said shelf of the safety support bears against said horizontal track angle.
  • 4. The system of claim 1 further comprising:a drum coupled to said support shaft; and a cable having a first end that wraps around the drum and a second end coupled to one of said sectional door panels.
  • 5. The system of claim 4 further comprising:a door frame member fixed to said one of said sectional door panels, the door frame member having an edge; and a cable bracket coupled to said second end of the cable and to said door frame member, the cable bracket having a hook which engages said edge of the door frame member to prevent release of the cable bracket from said door frame member while the cable is under tension.
  • 6. The system of claim 4 wherein the second end of the cable further comprises a curled portion to prevent the cable from straightening and coming off the drum.
  • 7. The system of claim 5 wherein the edge of the door frame member is located at the bottom of the door frame member, and the hook of said cable bracket hooks under said edge of the door frame member.
  • 8. The system of claim 5 wherein the cable bracket further comprises a bottom bearing plate that bears up against said one of said sectional door panels while the cable is in tension.
  • 9. The system of claim 1 wherein the bracket further comprises a hole through which the support shaft is placed.
  • 10. The system of claim 1 wherein the support track further comprises a latch aperture placed within a portion of the support track, said latch aperture being designed to receive a latch bar mounted to one of the sectional door panels.
  • 11. A system comprising:a plurality of pivotally connected sectional door panels; a support track through which the plurality of sectional door panels travel between an open and a closed position, said support track having an edge; a torsion shaft for transmitting torque; a torsion spring having a stationary end and a rotatable end, the rotatable end being fixed to the torsion shaft; and a lock-on side bearing bracket coupled to the stationary end of the torsion spring, said side bearing bracket having a hook and a tab that together bear against said support track to prevent rotation of said side bearing bracket with respect to the support track, said hook being wrapped under said edge of the support track, and said tab being juxtaposed against a surface of said support track.
  • 12. The system of claim 11 wherein the support track comprises a horizontal track angle and wherein said hook and tab of the side bearing bracket bear against said horizontal track angle.
  • 13. The system of claim 11 wherein said tab is substantially planar and extends substantially perpendicularly from the lock-on side bearing bracket.
  • 14. The system of claim 11 further comprising a spring anchor bracket fixed to the stationary end of the torsion spring and adjacent to the lock-on side bearing bracket.
  • 15. The system of claim 11 further comprising:a cable drum connected to the torsion shaft such that rotation of the cable drum causes rotation of the torsion shaft and rotation of the torsion spring; and a lift cable having a first end coupled to the cable drum and a second end coupled to one of said sectional door panels.
  • 16. The system of claim 15 further comprising:a door frame member fixed to said one of said sectional door panels, the door frame member comprising an edge; and a cable bracket connected to said second end of the lift cable, the cable bracket having a hook which engages said edge of the door frame member to prevent, when the lift cable is under tension, the cable bracket and lift cable from disassociating with said one of said sectional door panels.
  • 17. The system of claim 15 wherein the second end of the lift cable further comprises a curled portion to prevent the lift cable from straightening and coming off the cable drum.
  • 18. A system comprising:a plurality of pivotally connected sectional door panels; a support track in which the plurality of sectional door panels travel between an open and a closed position; a torsion spring assembly for moving the plurality of sectional door panels between said open and closed positions, said assembly including a rotatable support shaft and a torsion spring, said torsion spring having a first end and a second end, said first end being mounted to the rotatable support shaft; a drum coupled to the support shaft of the torsion spring assembly; a cable having a first end connected to the drum and a second end coupled to one of said sectional door panels; a door frame member fixed to said one of said sectional door panels, the door frame member having an edge; and a cable bracket coupled to said second end of the cable and to said door frame member, the cable bracket having an upwardly curving hook which bears against said edge of the door frame member to prevent release of the cable bracket from said door frame member while the cable is under tension.
  • 19. The system of claim 18 wherein the edge of the door frame member is situated above the hook.
  • 20. The system of claim 18 wherein the hook wraps around the edge of the door frame member even when the cable is not under tension.
  • 21. The system of claim 18 wherein the hook further comprises a notch specifically shaped to receive the edge of the door frame member.
  • 22. The system of claim 18 wherein the second end of the cable further comprises a curled portion.
  • 23. The system of claim 18 further comprising a side bracket fixed to the second end of the torsion spring, the side bracket having a safety support, said safety support comprising a hook and a tab that together bear against the support track to prevent the side bracket from moving with respect to the support track.
  • 24. The system of claim 18 wherein said one of said sectional door panels comprises a bottom surface, and said cable bracket further comprises a bottom bearing plate that bears against said bottom surface while the cable is in tension.
  • 25. The system of claim 18 wherein the support track further comprises a latch aperture placed within a portion of the support track, said latch aperture being formed to receive a latch bar mounted to one of the sectional door panels.
  • 26. A system comprising:a plurality of pivotally connected sectional door panels; a support track in which the plurality of sectional door panels travel between an open and a closed position; a torsion spring assembly for moving the plurality of sectional door panels between said open and closed positions, said assembly including a rotatable support shaft and a torsion spring, said torsion spring having a first end and a second end, said first end being mounted to the rotatable support shaft; a drum coupled to the support shaft of the torsion spring assembly; a cable having a first end connected to the drum and a second end coupled to one of said sectional door panels; a door frame member fixed to said one of said sectional door panels, the door frame member having a bottom edge; a cable bracket coupled to said second end of the cable, the cable bracket having a hook which moves upwardly against said edge of the door frame member to prevent, while the cable is under tension, the cable bracket and cable from disassociating with said one of said sectional door panels; and a bottom bearing plate on said cable bracket for bearing against a bottom surface on said one of said sectional door panels while said cable is in tension.
  • 27. The system of claim 26 wherein the hook wraps under the edge of the door frame member even when the cable is not under tension.
  • 28. The system of claim 26 further comprising a side bracket that is fixed to the second end of the torsion spring, the side bracket including a safety support comprising a hook which bears against the support track to prevent the side bracket from rotating with respect to the support track.
  • 29. The system of claim 28 wherein said safety support further comprises a tab having a substantially planar surface that bears against the support track.
  • 30. A system comprising:a plurality of pivotally connected sectional door panels; a support track in which the plurality of sectional door panels travel between an open and a closed position; a torsion shaft for transmitting torque; a torsion spring having a stationary end and a rotatable end, the rotatable end being fixed to the torsion shaft; a drum coupled to the torsion shaft such that rotation of the drum causes rotation of the torsion shaft and rotation of the torsion spring; a cable having a first end coupled to the drum and a second end coupled to one of said sectional door panels; a door frame member fixed to said one of said sectional door panels; and a cable bracket connected to said second end of the cable, the cable bracket having a bottom bearing plate for bearing against a bottom surface on said one of said sectional door panels while said cable is under tension.
  • 31. The system of claim 30 wherein the cable bracket is connected to the second end of the cable via a clevis pin and a cotter pin.
  • 32. The system of claim 30 wherein the drum is removably mounted to the torsion shaft.
  • 33. A system comprising:a plurality of pivotally connected sectional door panels; a support track in which the plurality of sectional door panels travel between an open and a closed position, the support track including a horizontal track angle; a torsion shaft for transmitting torque; a torsion spring having a stationary end and a rotatable end, the rotatable end being fixed to the torsion shaft; a lock-on side bearing bracket coupled to the stationary end of the torsion spring, said side bearing bracket having a hook and a tab that together bear against said horizontal track angle to prevent rotation of said side bearing bracket with respect to the support track, said hook being wrapped under an edge of the horizontal track angle, and said tab being juxtaposed against a surface of said horizontal track angle; a drum coupled to the torsion shaft such that rotation of the drum causes rotation of the torsion shaft and rotation of the torsion spring; a cable having a first end coupled to the drum and a second end coupled to one of said sectional door panels; a door frame member fixed to said one of said sectional door panels, the door frame member having an edge; a lock-on bottom bracket coupled to said second end of the cable and to said door frame member, the lock-on bottom bracket having an upwardly curving hook which moves upwardly against said edge of the door frame member to prevent release of the lock-on bottom bracket from said door frame member while the cable is under tension; and a bottom bearing plate on said lock-on bottom bracket for bearing against a bottom surface on said one of said sectional door panels while said cable is in tension.
  • 34. A method comprising:supporting, via a support track, a plurality of pivotally connected sectional door panels; moving, via a torsion spring and a cable, said sectional door panels between an open and a closed position; anchoring said torsion spring with a bracket coupled to said torsion spring; securing said bracket with a tab extending from said bracket, said tab being juxtaposed against a surface of said support track; and stabilizing said bracket with a hook that operates together with the tab to prevent the bracket from rotating with respect to the support track, the hook wrapping around an edge of the support track.
  • 35. The method of claim 34 wherein said step of securing further comprises bearing against said surface of said support track with a substantially planar surface on said tab.
  • 36. The method of claim 34 further comprising:securing, via a cable bracket, one end of said cable to a door frame member that is fixed to one of said sectional door panels; and reinforcing the connection between the cable bracket and door frame member with an upwardly curving hook and a bottom bearing plate on the cable bracket, said upwardly curving hook locking on to a bottom edge of the door frame member while the cable is under tension, and said bottom bearing plate bearing against a bottom surface of said one of said sectional door panels.
  • 37. The method of claim 36 further comprising stabilizing said cable via a curl in said end of the cable.
  • 38. A method comprising:supporting, via a support track, a plurality of pivotally connected sectional door panels; securing, via a cable bracket, one end of a cable to a door frame member that is fixed to one of said sectional door panels; lifting, via a torsion spring and said cable, said sectional door panels between an open and a closed position; and reinforcing the connection between the cable bracket and door frame member with a hook on the cable bracket, said hook locking on to a bottom edge of the door frame member while the cable is under tension.
  • 39. The method of claim 38 further comprising preventing, via a bottom bearing plate that bears upward against a bottom surface of said one of said sectional door panels when said cable is under tension, the cable bracket from disassociating with said one of said sectional door panels.
  • 40. The method of claim 38 further comprising stabilizing said cable via a curl in said end of the cable.
  • 41. A method comprising:supporting, via a support track, a plurality of pivotally connected sectional door panels; rotating, via a torsion spring, a support shaft that, in turn, rotates a drum coupled to the support shaft; winding, via said step of rotating, a cable around the drum, said cable having a first end connected to the drum and a second end; lifting, via said step of rotating, said sectional door panels, said second end of the cable being coupled to a door frame member on one of said sectional door panels; anchoring said torsion spring with a bracket coupled to said torsion spring; securing said bracket with a tab extending from said bracket, said tab being juxtaposed against a surface of said support track; stabilizing said bracket with a hook that operates together with the tab to prevent the bracket from rotating with respect to the support track, the hook wrapping around an edge of the support track; and reinforcing the connection between the cable bracket and said door frame member with a hook on the cable bracket, said cable bracket hook locking on to a bottom edge of the door frame member while the cable is under tension.
  • 42. The method of claim 41 further comprising preventing, via a bottom bearing plate that bears upward against a bottom surface of said one of said sectional door panels when said cable is under tension, the cable bracket from disassociating with said one of said sectional door panels.
  • 43. The method of claim 41 further comprising stabilizing said cable via a curl in said second end of the cable.
RELATED APPLICATION

This application claims priority to and is a continuation-in-part of the U.S. patent application Ser. No. 09/547,430 filed Apr. 12, 2000, now U.S. Pat. No. 6,401,793 and titled SPRING FORCE SAFETY LOCKING SYSTEM FOR SECTIONAL DOORS.

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Continuation in Parts (1)
Number Date Country
Parent 09/547430 Apr 2000 US
Child 10/165005 US