Information
-
Patent Grant
-
6401793
-
Patent Number
6,401,793
-
Date Filed
Wednesday, April 12, 200024 years ago
-
Date Issued
Tuesday, June 11, 200222 years ago
-
Inventors
-
Original Assignees
-
Examiners
Agents
- Kirton & McConkie
- Broadbent; Berne S.
-
CPC
-
US Classifications
Field of Search
US
- 160 188
- 160 189
- 160 190
- 160 191
- 160 192
- 160 193
- 160 201
- 049 200
- 049 505
- 292 174
- 292 DIG 46
-
International Classifications
-
Abstract
Hardware designed to improve safety and minimize the risk involved in installing, maintaining, and operating sectional doors that use spring mechanisms to facilitate door movement. A lock-on side bearing bracket bears up a spring mechanism on a garage door. This side bearing bracket includes a hook and a perpendicular tab to prevent the spring mechanism from dangerously releasing its energy when parts supporting the spring mechanism are removed or fail. A lock-on bottom roller bracket having a bottom bearing plate and a safety hook similarly prevents a potential, dangerous release of energy when the garage door lift cable is in tension. A safety latch with a latch bar and a latch cover acts as a lock for the garage door. The use of multiple safety features makes the garage door systems of the present invention particularly safe to operate and maintain.
Description
BACKGROUND
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.
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 may be 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. Furthermore, the present invention utilizes a lock-on side bearing bracket with an inventive locking device which prevents the spring mechanism from releasing its energy even when the track and spring mechanism is 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.
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. lift cable. At that point the bottomlock-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 a sectional door counter-spring system with novel safety features. 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
which is connected to a horizontal track
66
which includes an arcuate track
64
. 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, 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
. Arcuate track
64
which is at the rear part of horizontal track
66
is directly attached to vertical track
62
and horizontal track
66
through a connecting bracket
69
using conventional fasteners and may optionally be attached to the building structure or a track angle.
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 an inventive 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.
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
may be 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.
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 sectional door movably mounted within a support track system comprising:a plurality of sectional door panels, each pivotally attached to at least one adjacent sectional door panel; a support track, in which the plurality of sectional door panels travel between an open and closed position, and having a latch aperture placed within a portion of the support track; a door latch, mounted to one end of one of the sectional door panels, and having a latch bar that engages the latch aperture in a locking position; and a latch aperture cover, movably mounted to the support track adjacent the latch aperture, to cover the aperture when the latch bar is not therein engaged.
- 2. The sectional door movably mounted within a support track system of claim 1, further comprising:a torsion spring assembly, the assembly including a support shaft and at least one torsion spring mounted to the support shaft such that the torsion spring has a first end fixed to the support shaft, which can rotate in relation to the sectional door panels moving between the open and closed positions, and a second end that is fixed relative to the first end and the rotation of the support shaft during operation; and a bracket that is fixedly connected to the second end of the torsion spring, the bracket including a safety support comprising a hook which bears against the support track to prevent the bracket from rotating with respect to the support track.
- 3. The sectional door movably mounted within a support track system of claim 2, wherein said safety support of the bracket further comprises a tab adjacent the hook, the hook and tab operating together to bear against the support track.
- 4. The sectional door movably mounted within a support track system of claim 2, further comprising:a drum coupled to the support shaft of the torsion spring assembly; and a cable having a first end connected to the drum and a second end coupled to one of said sectional door panels.
- 5. The sectional door movably mounted within a support track system of claim 4, further comprising:a door bracket fixedly attached to said one of said sectional door panels, the door bracket including an edge; and a cable bracket connected to said second end of the cable, the cable bracket having a hook which engages said edge of the door bracket to prevent release of the cable bracket and cable from the sectional door panel while the cable is under tension.
- 6. The sectional door movably mounted within a support track system of claim 1, further comprising: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 tab structure which bears against said support track to prevent rotation of said side bearing bracket with respect to the support track, the side bearing bracket also having a bearing to rotatably support the torsion shaft.
- 7. The sectional door movably mounted within a support track system of claim 6, 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 connected to the cable drum and a second end coupled to one of said sectional door panels.
- 8. The sectional door movably mounted within a support track system of claim 7, further comprising:a door bracket fixedly attached to said one of said sectional door panels, the door bracket including an edge; and a cable bracket connected to said second end of the cable, the cable bracket having a hook which engages said edge of the door bracket to prevent release of the cable bracket and cable from the sectional door panel while the cable is under tension.
US Referenced Citations (19)