Upward acting sectional door

Information

  • Patent Grant
  • 6672362
  • Patent Number
    6,672,362
  • Date Filed
    Friday, November 10, 2000
    24 years ago
  • Date Issued
    Tuesday, January 6, 2004
    20 years ago
Abstract
An upwardly acting sectional door (24), including a plurality of panels (40), body portions (50) of the panels constructed of a flexible polymeric material and having a front surface (55), a cladding (80) covering the front surface of the body portions and having hooks (83, 84) at the upper and lower edges thereof, a hinge member (51) at an edge of the body portion operatively engaging the hooks of adjacent of the panels to provide relative pivotal motion between adjacent panels. Another embodiment is an upwardly acting sectional pan door (224) including, a plurality of panels (240), facers (250) of the panels defining a front surface of the door and having cooperatively engaging couplers (270) at the upper and lower edges thereof, stiles (280) at the ends of the facers receiving and attached to the facers, and hinge assemblies (290) located at the end stiles to provide relative pivotal motion between the stiles and the couplers of adjacent panels.
Description




TECHNICAL FIELD




The present invention relates to upward acting sectional doors. More particularly, the present invention relates to an upward acting sectional door having a flexibly hinged plastic core with metal cladding or a pan door with or without insulation. More particularly, the present invention relates to an upward acting sectional door having integral hinges that allow the door to pass through a very short transitional radius, a metal cladded exterior surface, interior insulation, if desired, and the capability of being packaged substantially preassembled, complete with a counterbalance system and operator installed.




BACKGROUND ART




There are numerous doors that are vertically oriented in the closed position and store in an open overhead position that are used as doors for buildings and trailers.




One common construction is a tilting, non-flexible one-piece door. This type of door may be of generally two constructions. The first is a center pivoting door that uses a framework to which the door is mounted that pivots on a horizontal axis proximate to the vertical center of the door. These doors require space immediately adjacent to the door on the inside and outside for the door to open and close. The action of the door makes entrapment possible at the sides and bottom of the door. The second type of one-piece door uses horizontal and vertical tracks to guide the door between open and closed positions. These doors do not require clearance space adjacent to the outside of the door but require a considerable amount of clearance space to the inside of the door to allow the door to open and close. These doors present the same potential entrapment dangers as the pivoting door. These types of doors have been used on buildings but are not suitable as trailer doors in that the inside clearance space needed to open and close the door would significantly decrease the payload of the trailer. Further, if the cargo shifted during transit, the door could be jammed in the closed position.




Another common type of door is a sheet door. Sheet doors have flexible door panels that are guided around rotatable guide wheels between the open and closed positions. When in the open position, the flexible door panel is substantially horizontal to maximize the height clearance in the doorway opening. These doors are made from a flexible plate material that requires reinforcement at the edges. The flexible plate material must be formed into a pivot strengthening profile to give the door adequate strength and must use a rather large drive wheel to move the flexible plates from the horizontal to vertical tracks and from the vertical to horizontal tracks as the door is opened or closed. While increasing headroom or decreasing the hang down of the door into the door opening, these doors are somewhat flimsy and noisy to operate. Moreover, the inability to move the plates through a conventional transitional radius necessitates the use of large diameter drive rollers on either side of the door consuming significant interior space. The bending of the plates around the drive rollers causes undesirable stress on the plates and precludes tolerance to above-normal wind pressure.




Sectional doors are well known in the art. One concern with sectional doors, however, is the entrapment of hands or fingers at the interfaces of the door sections and along the edges of the door. Pinch-resistant sectional doors have been developed with integrally formed section interfaces that eliminate the finger and hand entrapping gaps, but these doors still require additional hardware to perform this function. Similar hardware may be added to a conventional sectional door to perform the same function. To prevent entrapment at the edges of the door, longitudinal mating sections have been added to pinch resistant sectional doors and conventional sectional doors.




As a further disadvantage, sectional doors generally have hinges and other hardware mounted on the interior of the door. If used as a trailer door, this hardware may damage cargo within the trailer or interfere with door movement. Attempts have been made to remove this disadvantage by designing doors with continuous hinges. Generally, these hinges are constructed of polymeric material and may be an integral component of the door or installed as a separate component between the sections. Although these hinge designs can be flush with the back of the door, the pivot point established by the hinge is fixed, thereby creating stresses in the hinge and the hinge attachment areas.




Rolling doors made from a plurality of slats or a sheet of metal suffer a similar buildup of stresses in the hinge because they also have a fixed pivot point. Rolling doors, however, have the advantage of pinch resistance because they are made of a plurality of closely fitting slats. But, due to the shorter height of the slats, a large number of slats are necessary to cover the door opening resulting in the rolling door being heavier and more expensive than sectional doors. These doors also require extensive headroom to store the rolled up door when the door is in the open position. The large number of slats also increases the time necessary to manufacture and assemble these doors. Assembly is complicated by the fact that these doors require the slats to be individually longitudinally interlaced. This interlacing also results in an interconnection which transmits force between slats so that even a localized impact can result in damage to a number of adjacent panels. While the slats are often constructed of sheet steel offering little insulation, additional plastic insulated materials and insulation covers have been added to these types of doors. As will be appreciated, the addition of plastic insulating material increases the weight and complexity of the door, thereby increasing the cost to the manufacturer and the time necessary to manufacture the door. Further, these rolling door designs normally have fixed pivot points with no provision for reducing stresses in the area of the hinges.




Some sectional doors have utilized polymeric materials for door components, including the door sections. In one instance, a door has been constructed of blow-molded polymeric material sections for use on building structures such as industrial, commercial, and residential garages. In another instance door panels having a polyurethane rigid core with a polyvinylchloride front skin and a non-metallic rear skin have been proposed. The rigid polyurethane core unitizes the two skins to make the panel section into a rigid lightweight structure. These known designs require expensive equipment of considerable size, particularly to process a double car width door section. Further, these doors contain conventional hardware such as stiles and hinges, which protrude into the area adjacent the interior surface of the door. Overall, the main difference between a conventional sectional door and these doors is the use of polymeric sections.




Sectional doors with sections from 18-24 inches in height necessarily have a relative angular movement between sections of up to 78° when traversing the transitional radius between the open and closed positions. These angular movements of the sections alter the force required to move the door and put stress on the hinge and hinge mounting area. It has been recognized that hinges with multiple bend points may reduce the stress on hinge elements as well as hinges having a plurality of co-extruded polymers to achieve a hinge capable of continuous movements of up to 90° or more. The extruded thermoplastic hinge has improved ability to withstand flexure cycles at room temperature as well as low temperatures. This hinge comprises a flexible cross-section of polyester elastomer and a co-extruded section of rigid or semi-rigid thermoplastic material. This type of hinge design is more costly and care must be taken during the extrusion process to assure adequate bonding or encapsulation of the different polymers used to produce the hinge.




DISCLOSURE OF THE INVENTION




Therefore, an object of the present invention is to provide an upward acting sectional door in which the body of the door is an extruded corrugated polymer which provides an extent of insulation, without foamed insulating material and backing, as well as noise reduction for a quieter operating door than conventional sheet metal doors. Another object of the invention is to provide such a sectional door wherein the corrugated polymer has relatively high strength, is light weight, is low maintenance in not requiring painting, allows for expansion and contraction without warping the door, and can be produced at relatively low cost. A further object of the invention is to provide such a sectional door wherein the door has minimal intrusion interiorly of the door opening and may have a smooth interior surface which tends to avoid catching on objects in proximity to the interior surface which could cause damage to the object or the door. Yet another object of the invention is to provide such a sectional door wherein the polymer provides a movable pivot hinge function between the door sections.




Another object of the present invention is to provide such a sectional door having a body of corrugated polymer which can be coupled with an exterior metal cladding and/or tubular steel inserts to develop sufficient strength and rigidity for a particular door size and specifications. Yet a further object of the invention is to provide such a sectional door wherein end stiles, exterior metal cladding, and tubular steel inserts slide or snap into position to thereby eliminate the extensive use of fasteners or adhesives to interconnect the components of the door. Still another object of the invention is to provide such a sectional door which can be employed with conventional track configurations for sectional doors, but may mount the engaging rollers at substantially the centroid of the corrugated polymer body, whereby with the movable pivot hinge construction the door can negotiate a curved transitional track section between horizontal and vertical track section of approximately one half the normal radius.




Yet another object of the present invention is to provide such a sectional door which incorporates pinch resistant features at the juncture between the sections of the door. Another object of the invention is to provide such a sectional door which does not have projecting hardware at the ends of the door so that finger protection elements may be provided between the door edges and the vertical tracks. Still a further object of the invention is to provide such a sectional door that can employ known counterbalance systems and operators and will accommodate conventional lock systems and windows. Another object of the present invention is to provide such a sectional door which is of sufficiently light weight to be shipped completely assembled with the counterbalance system tensioned and with a motorized operator installed, if desired.




The present invention further provides a vertically operated door including a plurality of door sections rotatably attached to each other, each section having a front surface and a rear surface spaced from each other by an internal structure, the internal structure defining a plurality of encapsulated spaces between the front and rear surfaces which provide a thermal break therebetween.




A sectional door having a plurality of panels joined by a hinge, the hinge having a flexible member extending between adjacent sections; the member defining a first axis and a second axis about which the sections pivot, wherein the axes are moveable during operation of the door such that stresses within the hinge caused by the rotation of the sections are relieved by movement of and about the axes.




A sectional door having a pair of opposed tracks for guiding the door between a closed position and an open position, the tracks having an inner surface, an insert received within the tracks with a polymeric member having a first portion that defines the inner surface of the track and a second portion extending axially from the first portion to at least partially cover the door to effect finger protection.




A door selectively moveable between an open position and a closed position relative to an opening including, a plurality of elongate corrugated horizontal panels pivotally connected at top and bottom edges of adjacent panels by a hinge member defining a first axis and a second axis wherein the first axis and second axis are moveable relative to each other such that stresses within the hinge member created by the pivotal movement of adjacent panels are relieved by the movement of the hinge member about the first and second axes.




A cladding member, in a door system, a cladding member including a generally planar body having a top edge and a bottom edge; a first hook extending from the top edge; and a second hook extending from the bottom edge, the hooks adapted to attach the cladding members to the door.




An end stile in a door system having an open ended channel member adapted to engage the ends of the door sections, the channel members on adjacent sections being in pivotal relationship to each other, each member having a front facer and a rear facer spaced from the front facer by an end extending therebetween, whereby the stiles cover the sides of the sections and move with the sections.




A pre-packaged door kit having a pair of spaced jambs spanned by a header; a first pair of tracks adjacent the jambs, a door having a plurality of corrugated polymer panels pivotally joined by a hinge member, the door being received in the tracks; a counterbalance system and operator attached to the header and operatively engaging the door; a second pair of tracks adapted to be attached to the first and tracks releasably attached to the door; and a back bar adapted to be attached to the second tracks releasably attached adjacent the door.




In a door having a plurality of sections including a top section, the sections being mounted between a pair of tracks which guide the door between a closed and an open position, a pivotal roller attached to the top section by an arm rotatably attached to the top section at one end and a wheel rotatably attached to the arm at the other end, wherein the wheel fits within the tracks causing the arm to pivot from a generally perpendicular position relative to the top section when the door is in the closed position to a generally planar position when the door reaches the open position.




An object of the present invention is to provide as an alternate a sectional pan door system which may be provided with or without insulation. Another object of the invention is to provide such an insulated sectional pan door wherein conventional foam insulation is mechanically retained by door panel components without the necessity for employing adhesives. A further object of the invention is to provide a sectional pan door which has minimal intrusion interiorly of the door opening, which works with a conventional track, and which can traverse a curved transitional track section having a greatly reduced radius without stressing the hinges or hinge areas. Yet another object of the invention is to provide a sectional pan door which is hinged at the end stiles, has pivotal closure assemblies extending the lateral extent of the panels at the edges to provide a pinch-resistant configuration, and may have spaced coupler elements to stabilize the pivot axis of the pivotal closure assemblies.




A further object of the invention is to provide a sectional pan door which does not have projecting hardware at the end stiles so that finger protection elements may be provided between the door edges and the vertical tracks. Another object of the invention is to provide a sectional pan door that can be adapted to a tension-type system for resisting wind loads through the roller assemblies and have a combined roller assembly and counterbalance system cable-securing device at the lower corners of the door. A still further object of the invention is to provide a sectional pan door that is sufficiently lightweight to be shipped completely assembled with a counterbalance system and motorized operator installed and connected, that is relatively inexpensive but strong, and that may be quickly and easily installed.




In general, the alternate embodiment contemplates, an upwardly acting sectional pan door, including a plurality of panels, facers of the panels defining a front surface of the door and having cooperatively engaging couplers at the upper and lower edges thereof, stiles at the ends of the facers receiving and attached to the facers, and hinge assemblies located at the end stiles to provide relative pivotal motion between the stiles and the couplers of adjacent panels.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a perspective view depicting an upward acting sectional door embodying concepts of the present invention shown packaged for shipment as an assembled unit including the track system, a pre-tensioned counterbalance system, and an operator.





FIG. 2

is a perspective view depicting the door according to

FIG. 1

as it might be installed with the horizontal tracks in operative position and braced with a back bar.





FIG. 3

is a fragmentary sectional side view taken substantially along line


3





3


in

FIG. 2

depicting details of one section of the door including the corrugated door section body and the metal cladding.





FIGS. 4A through 4D

are a series of sectional side views similar to

FIG. 3

depicting the door hinge and moving pivot points as adjacent door sections rotate relative to one another as the door moves through the transition portion of the tracks.





FIG. 5

is a fragmentary partially exploded perspective view depicting installation of the end stile and a roller into the body portion of the door.





FIG. 6

is a fragmentary sectional view taken substantially along line


6





6


of

FIG. 2

depicting the relationship of the roller tracks, end stile, and jambs of the door, together with the track liner.





FIGS. 7A-7E

are side elevational views depicting the sequence of steps in attaching the metal cladding to the body portion of the door.





FIG. 8

is a fragmentary partially schematic side elevational view depicting the movement of the top panel of the door and showing the spring loaded rotating roller arm at the closed position of the door, the open position of the door and intermediate positions.





FIG. 9

is a fragmentary top end and rear view showing a modified roller assembly for wind-resistant applications in an exploded configuration.





FIG. 10

is a fragmentary sectional view taken substantially along the line


10





10


of

FIG. 9

showing the modified roller assembly and its relation to a reinforcing member and a vertical track section.





FIG. 11

is a perspective view depicting an alternate, pan door embodiment of upward acting sectional door embodying concepts of the present invention as it might be installed with the horizontal tracks in operative position and braced with a back bar.





FIG. 12

is an enlarged fragmentary perspective view of the upper corner of the door of

FIG. 11

showing particularly the pivotal roller assembly mounted proximate the top of the door.





FIG. 13

is an enlarged fragmentary sectional view taken substantially along line


13





13


of

FIG. 11 through a

panel and top and bottom pivotal closure assemblies at the location of coupler clips.





FIGS. 14A through 14D

are a series of side views similar to

FIG. 13

depicting positions of the pivotal closure and the coupler clips between panels as adjacent door panels rotate relative to one another as the door moves through the transition portion of the tracks.





FIG. 15

is an exploded fragmentary perspective view of a plurality of adjacent panels showing the roller assemblies mounted between the panels on the end stiles.





FIG. 16

is an enlarged rear perspective view of an end stile for the door of

FIG. 11

showing the top and bottom hinge elements.





FIG. 17

is a side elevational view of the end stile of

FIG. 16

showing structural details thereof.





FIG. 18

is an enlarged front perspective view of the end stile of

FIG. 16

showing additional structural details thereof together with the placement of insulating material in relation thereto.





FIG. 19

is an enlarged fragmentary perspective view of a pair of adjacent panels showing details of the roller assemblies and the relation with the hinge elements of adjacent panels.





FIG. 20

is an enlarged fragmentary perspective view of a bottom and rear corner of the door of

FIG. 11

showing the combined track engaging roller assembly and associated cable bracket for securing a counterbalance cable.





FIG. 21

is a sectional view of the bottom panel roller and cable bracket taken substantially along the line


21





21


of FIG.


20


.





FIG. 22

is an enlarged fragmentary sectional view taken substantially along the line


22





22


of FIG.


11


through the vertical track, roller assembly and a portion of a door panel showing details thereof.





FIG. 23

is an enlarged fragmentary sectional view of the door taken substantially along the line


23





23


of

FIG. 11

showing the relation between the end stiles and the cladding or facer material in the hinge areas.











DETAILED DESCRIPTION




An upward acting metal cladded sectional door system embodying concepts of the present invention is generally indicated by the numeral


20


in

FIG. 1

of the drawings. The door system


20


is positioned and mounted for opening and closing movement in a building or trailer by a peripheral door frame, generally indicated by the numeral


21


. The frame


21


consists of a pair of spaced vertical track framers


22


,


22


that, as seen in

FIGS. 1 and 2

, are generally parallel and extend vertically upwardly relative to a supporting surface such as a floor or the bed of a trailer (not shown). The vertical track framers


22


,


22


are spaced and joined proximate their vertical upper extremity by a header framer


23


to thereby define the generally inverted U-shaped frame


21


for mounting a door, generally indicated by the numeral


24


. Frame


21


may be constructed of metal or other relatively high strength, rigid material for purposes of reinforcement, attachment to a building or vehicle, and facilitating the attachment of elements involved in supporting and controlling the door


24


.




The header framer


23


may advantageously mount a counterbalance system, generally indicated by the numeral


25


, that interacts with the door


24


to facilitate raising and lowering of the door


24


in a manner well-known to persons skilled in the art. While a counterbalance system according to applicants' assignee's U.S. Pat. No. 5,419,010 is shown for exemplary purposes and the disclosure therein is incorporated herein by reference, it will be appreciated that any of a variety of different types of counterbalancing systems may be employed, as long as interference with the structure of the door system hereinafter described is, or can be avoided.




Flag angles


26


,


26


are provided to partially support roller tracks, generally indicated by the numerals


27


,


27


, which are positioned to either side of the door


24


. Each of the roller tracks


27


,


27


include a substantially vertical track section


28


(see

FIG. 6

) formed in vertical track framers


22


,


22


, a substantially horizontal track section


29


and transition track section


30


interposed therebetween. The roller tracks


27


,


27


, in a known manner, thus support and direct travel of the door


24


in moving from the closed vertical position depicted in

FIG. 2

, associated with vertical track sections


28


,


28


of roller tracks


27


,


27


through transition track sections


30


,


30


to the open, horizontal position associated with horizontal track sections


29


,


29


seen in FIG.


2


. The ends of horizontal track sections


29


,


29


displaced from the door


24


are joined and supported by a back bar


31


attached directly or indirectly to the ceiling or walls of a structure in which the door system


20


is installed. The back bar


31


may be attached to vertical track framers


22


,


22


as seen in

FIG. 2

when door system


20


is packaged for shipping. The horizontal track sections


29


,


29


may be attached to the frame


21


as seen in

FIG. 1

when the door


20


is packaged for shipping. Further, the counterbalance system


25


may be installed and tensioned in the packaged shipping condition seen in FIG.


1


.




For exemplary purposes, an eight panel sectional door


24


is shown in

FIGS. 1 and 2

of the drawings; however, it will be appreciated that more or less panels may be employed in sectional doors of this type depending upon the height of the door opening and related considerations. As depicted, the door


24


has a plurality of panels or sections, generally indicated by the numeral


40


, including a first or top panel


41


, a second panel


42


, a third panel


43


, a fourth panel


44


, a fifth panel


45


, a sixth panel


46


, a seventh panel


47


, and an eighth or bottom panel


48


. Each of the panels


40


have generally the same essential configuration. Thus, only a single panel, panel


47


, will be described in detail for exemplary purposes.




As shown in

FIG. 3

, each panel


40


has a body portion, generally indicated by the numeral


50


, with hinge elements, generally indicated by the numeral


51


, located at the upper edge thereof. The body portions


50


are constructed of a polymeric material and have generally continuous outer surfaces. The body portions


50


may be extruded from thermoset or thermoplastic polymers or other suitable materials. The polymeric material preferably has a flex modulus similar to polypropylene resin so that the angular flexing of the hinge elements


51


described hereinafter during traverse through the transitional radius between the horizontal and vertical positions of the door can be accommodated without exceeding the flex memory of the polymeric material. One preferred material for the polymeric body portion


50


is a homopolymer polypropylene. While the height of body portions


50


may be in the 6 inch to 18 inch range, the height is preferably from approximately 9 inches to 12 inches, for purposes of permitting optimum radius curved transition track sections


30


,


30


.




Internally, the body portion


50


is preferably ribbed, honeycombed, or otherwise reinforced and segregated with internal dividers


52


that provide voids


53


between the surfaces of the door


24


. The voids trap air between these surfaces providing an insulative break and reducing the rate of heat transfer between the surfaces of the door. It has been determined that these objectives can be met with a wide variety of internal structures with one example having the body portions


50


at least 0.75 inch in thickness with intersecting horizontal and vertical internal dividers


52


forming rectangular or square voids


53


having a width of at least 50% of the height or the thickness of body portion


50


and no more than 100% of the height of the voids


53


.




As previously indicated, the exterior surfaces of the door


24


include a front surface


55


and a rear surface


55


′ which are generally continuous and may be provided with recesses or other surface characteristics as desired. The surface characteristics may be aesthetic or used functionally such as for mounting hardware in the nature of locks, windows, reinforcing members or rollers on or within the door


24


. For example, a recess, generally indicated by the numeral


54


, may be provided in the rear surface


55


′ of the door


24


to receive members used to secure stiles.




As best seen in

FIGS. 3 and 5

, recess


54


is formed in the rear surface


55


′ of the door sections


40


for receiving a tab, generally indicated by the numeral


56


, formed on an end stile, generally indicated by the numeral


60


. The tab


56


and recess


54


are cooperatively formed such that the tab


56


may be insertably received within recess


54


and serve to hold the end stile


60


in place under normal operating conditions. Viewed axially from its open end (FIG.


3


), recess


54


generally necks inward and then mushrooms laterally outward. As shown, the recess


54


is defined by opposed walls


57


including a pair of shoulders


58


,


58


that taper inwardly to form a neck


59


of the opening


54


. Lands


61


extend outwardly from the shoulders


58


at the neck


59


to the walls


57


. The walls


57


extend substantially perpendicular to lands


61


and may join an internal rib


63


of the door section


40


to complete the recess


54


. As shown, selected surfaces of these structures may be rounded to facilitate insertion of tab


56


, such as, the shoulders


58


and the joint between walls


57


and the internal rib


63


. The lands


61


are preferably left square to securely grip the tab and prevent any extent of movement thereof.




Referring to

FIG. 5

, it may be seen that tab


56


may be provided with corresponding features such that the tab


56


fits snugly within recess


54


. In particular, tab


56


is provided with neck portions


64


that expands outwardly to form a head portions


65


that extend laterally outwardly beyond the necks


64


. The leading edges


67


,


67


of the head portions


65


,


65


may be tapered inwardly to facilitate insertion and terminate in flats


66


which abuts rib


63


. When inserted, head portions


65


,


65


fit within the widened opening of recess


54


adjacent the walls


57


and lands


61


. It will be appreciated that a single recess


54


may be formed to insertably receive the tab


56


in a snap-in type motion, or, as shown, recess


54


may extend axially in a channel-like fashion such that tabs


56


may be slidably inserted axially within the channel.




Further, the exterior surface


55


of the sections


40


may be provided at the lower and upper extremities with recessed lands


68


, and rounded shoulders


69


, respectively to interface with a portion of the hinge


51


extending between the adjacent door sections


40


to form a one piece door


24


. The hinge


51


may be a separate member attached between the sections


40


or may be integrally formed with one of the sections


40


. A plurality of hinges


51


might be spaced along the width of each door section


40


or hinge


51


may extend the entire width of the section


24


as shown herein.




As shown, hinge


51


is constituted in vertical cross-section primarily of a relatively large-radiused, deformable double loop, generally indicated by the numeral


70


. As shown, the double loop may be a continuation of rounded shoulders


69


at the upper extremity of the sections


40


and therefore constituted of the same material having the flexing characteristics described hereinabove. Referring particularly to

FIGS. 4A-4D

, the double loop


70


of hinge


51


has an upper flat curve segment


71


which extends upwardly and inwardly from outer surface


55


of the body portion


50


of door sections


40


. The upper flat curve segment


71


transcends into a semicircular segment


72


which is centered about an axis


73


which is preferably located substantially centrally of the thickness of the door sections


40


. The semicircular segment


72


transcends into a lower flat curved segment


74


which is directed generally back toward the front surface


55


of door sections


40


. Together the segments


71


,


72


, and


74


define the inner leg


75


of the double loop


70


.




The double loop


70


has an outer leg


75


′ which, as can be seen in

FIG. 4A

, that is spaced from and substantially parallels the inner leg


75


when the sections


40


of sectional door


24


are in a substantially planar alignment. The legs


75


and


75


′ are connected by a hairpin curve return


76


which merges into a return lower flat curve segment


77


that substantially parallels the lower flat curved segment


74


of inner leg


75


. The return lower flat curved segment


77


merges into a return circular segment


78


which parallels semicircular segment


72


and a portion of upper flat curve segment


71


of the inner leg


75


. The outer leg


75


′ of double loop


70


terminates in an angularly upwardly disposed locking tab


79


which is located along a portion of the front surface


55


of the bottom of the door sections


40


and retained in a manner described hereinafter.




The sections


40


of door


24


have a cladding, generally indicated by the numeral


80


, which covers the front surface


55


of the body portions


50


and constitutes an operative portion of the hinge elements


51


. The cladding


80


operates to provide rigidity to the sections


40


as well as protection from the elements. While the cladding


80


might be constructed of various materials to achieve the desired performance, a sheet metal of a type commonly used as facer material for sectional overhead doors is a satisfactory selection for the cladding


80


. Referring particularly to

FIGS. 3

,


4


, and


7


, the cladding


80


for body portion


50


has a substantially planar front cover


81


which is adapted to overlie the front surface


55


of the body portion


50


. The top and bottom edges of the cladding


80


as viewed in the figures have a first hook member


83


and a second hook member


84


, respectively. As best seen from

FIGS. 7A-7E

, the first and second hook members


83


,


84


are generally semicircular and preferably configured to mate with portions of inner leg


75


and outer leg


75


′ which encase the first and second hook members


83


,


84


. In particular, hook members


83


,


84


generally conform to the circular segments


72


and


78


of inner leg


75


and outer leg


75


′, respectively, of the double loop


70


. As best seen in

FIGS. 3 and 4

, the first hook member


83


at the top of a section


40


fits over and is adjacent to the upper flat curve segment


71


and a portion of semicircular segment


72


of inner leg


75


. The second hook member


84


at the bottom of sections


40


conforms to the circular segment


78


of outer leg


75


′ interiorly thereof and outwardly of the first hook member


83


of an adjacent door section


40


.




The installation of the cladding


80


on the body portion


50


of each door section


40


is effected in the manner depicted in

FIGS. 7A-7E

of the drawings. In

FIG. 7A

the cladding


80


is brought into a general alignment with the front surface


55


of body portion


15


of a door section


40


. As seen in

FIG. 7B

the first hook member


83


is brought into contact with inner leg


75


and outer leg


75


′ of the resiliently deformable double loop


70


to produce a separation between the inner leg


75


and outer leg


75


′ as depicted in FIG.


7


B.

FIG. 7C

depicts the inner leg


75


and outer leg


75


′ of the double hook


70


having been displaced a sufficient distance such as to receive the first hook member


83


within the confines thereof. In

FIG. 7D

, the second hook member


84


of cladding


80


is brought closer into alignment with body portion


50


such that inner leg


75


and outer leg


75


′ of double loop


70


return to the undistorted normal position thereof as depicted in

FIG. 7A

, except that first hook member


83


is interposed between the legs


75


,


75


′. Thereafter, the second hook member


84


is temporarily downwardly displaced from the normal position shown in

FIG. 7D

a sufficient distance to clear the land


68


at which time cladding


80


has the front cover


81


brought into engagement with the front surface


55


of body portion


50


which contemporaneously permits the second hook member


84


to snap into position against the complementary configured land


68


as seen in FIG.


7


E.




With the cladding


80


assembled on body portion


50


a panel


40


is fully assembled and ready for attachment to an adjoining panel as seen in FIG.


3


. In this respect, the double loop


70


of the lower of two panels has the outer leg


75


′ slid between the land


68


and the second hook member


84


while the locking tab


79


is simultaneously slid between front cover


81


of cladding


80


and the front surface


55


of body portion


50


. As thus positioned the locking tab


79


as restrained by the front cover


81


of cladding


80


which retains the double loop


70


such as to maintain the adjacent door sections


40


in joined pivotal relationship as depicted in FIG.


3


.




The operation of hinges


51


between adjacent panels


40


during movement of the sectional door


24


between the closed and open positions is best seen in

FIGS. 4A-4D

.

FIG. 4A

shows adjacent panels


40


in a planar position as would exist in the open or closed position of the door.

FIGS. 4B-4D

depict the angular inclination which takes place between adjacent panels


40


as the door transcends through transitional track sections


30


joining the vertical track sections


28


and horizontal track sections


29


, with a maximum angular orientation between adjacent panels


40


of approximately 75-80° being depicted in FIG.


4


D.




The double loop


70


and the hook members


83


,


84


are in a normal unstressed condition in the planar orientation of adjacent panels


40


as seen in FIG.


4


A. As an angle develops between adjacent panels


40


during movement of the door


24


the hairpin curve return


76


pivots about axis


73


moving the hairpin curve return


76


to the left and upwardly as depicted in FIG.


4


B. As the panels


40


experience progressively increasing angularity in moving to the positions depicted in


4


C and


4


D, the axis


73


and the hairpin curve return


76


retain substantially the same positions depicted in FIG.


4


B. As the angularity between panels


40


increases between the orientation of FIG.


4


B and the orientation of

FIG. 4C

, the return lower flat curved segment


74


and a portion of semicircular segment


72


of outer leg


75


′ straightens to an extent toward linearity such as to open a crescent-shaped gap


85


between the first hook member


83


and the second hook member


84


. The flex modulus of the material of the flexible double loop


70


and the length of the segments


74


,


72


, which are the subject of the distortion, disperse the stress relief over a sufficient area such that the flex memory of the material of the outer leg


75


′ is not exceeded. In progressing from the angularity depicted in

FIG. 4C

to the maximum angularity of

FIG. 4D

the return lower flat curved segment


74


and semicircular segment


72


continue to straighten toward a linear orientation such that the crescent-shaped gap becomes larger as the second hook member


84


which remains relatively undistorted in essentially pivoting about hairpin curve return


76


may separate from the adjacent portion of outer leg


75


′ in the area of the transition between the return lower flat curved segment


74


and the return semicircular segment


72


. A reverse progression from

FIGS. 4D-4A

takes place as the door


24


and particularly the adjacent panels


40


progress from the maximum angular displacement of


4


D to the planar configuration of FIG.


4


A.




It will be appreciated that the precise dimensions of the double loop


70


and the hook members


83


,


84


of hinge element


51


may be configured such that no external or internal pinch points are created which could entrap a person's finger. More specifically, the hook members


83


and


84


of the cladding


80


remain in sufficiently close proximity during the entire pivotal movement of adjacent panels


40


such that the maximum separation between the nose


86


of cladding


80


and the first hook member


83


is at all times less than the maximum permissible separation specified by industry standards for a pinch-resistant configuration. As seen in

FIG. 3

, the cladding


80


may have an offset


87


at the transition between the front cover


81


and the first hook member


83


to receive the nose


86


so as to provide a flush front surface of cladding


80


of adjacent panels


40


at their juncture. The cooperative engagement of nose


86


with offset


87


also serves to prevent the transfer of moisture and air from the outside elements interiorly of the door


24


.




In addition to cladding


80


covering the outer surface


55


of the door


24


, the end stiles


60


may be installed to cover the ends


31


of the panels


40


of the door


24


and provide a planar exterior end surface. As shown in

FIGS. 5 and 6

, the end stiles


60


may be generally U-shaped members sized to cover the ends


31


of the door sections


40


and may include front and rear flanges


91


and


92


that extend at least partially over the front and rear surfaces


55


,


55


′ of the door


24


. As shown in

FIG. 5

, the rear flange


92


may extend inwardly to a greater extent than the front flange


91


. To secure the end stile


60


, the rear flange


92


may be provided with tab


56


designed to fit within recess


54


in the rear surface


55


′ of the door


24


, as described above. To allow inward rotation of an upper adjacent section


40


, the rear flange


92


extends vertically upwardly to a lesser extent than the front flange


91


(FIG.


5


). In this way, a gap is created between adjacent end stiles on the rear surface


55


′ of the door


24


. Front flange


91


, on the other hand, extends nearly the entire length of the end


93


of stile


60


, such that the adjacent stiles are in close proximity to each other on the front of door


24


when adjacent panels


40


are in planar orientation. As best shown in

FIGS. 5 and 9

, the end


93


of end stile


60


extends upwardly above front and rear flanges


91


,


92


and has a rounded extremity


90


such that it may pivot within a rounded recess


90


′ formed at the lower portion of end


93


of an adjacent end stile


60


. As best shown in

FIG. 9

, the end


93


of end stile


60


may be provided with an opening


94


to allow insertion of a roller assembly, generally indicated by the numeral


95


, as will be described in detail below. In addition to providing a protective surface for the door


24


, cladding


80


and end stiles


60


strengthen and stabilize the door


24


.




To further strengthen the door


24


and reduce flexure of its sections


40


, reinforcing members


96


may be inserted within the voids


53


between the internal dividers


52


of the door


24


or within the double loop


70


of hinges


51


. In the embodiment shown, the reinforcing rod or tube


96


is inserted within the double loop


70


of hinges


51


and extends substantially the entire width of the door


24


. As shown in

FIG. 5

, the reinforcing rod


96


may extend slightly beyond the width of the door


24


at either side thereof. The reinforcing member


96


may be inserted before installation of the end stiles


60


such that the end member


93


of end stile


60


abuts the exposed end


97


of the reinforcing member


96


.




Roller assembly


95


may be inserted into the double loop


70


of the hinge member


51


or may be inserted into the reinforcing member


96


. As shown in

FIG. 6

, a cylindrical reinforcing member or insert


98


may be located in a section


40


, within the hinge


51


, and sized to receive a roller shaft


99


of roller assembly


95


therein. As shown, the insert


98


may have a tapered end


100


to facilitate placement of the insert


98


within the hinge


51


. At its opposite end, the insert


98


is provided with an annular flange


102


extending radially outwardly from the end of the insert


98


. This flange


102


may rest adjacent to the end


31


of door section


40


and preferably against the outside surface of end


93


of stile


60


.




While the reinforcing member


96


is a convenient location to insert a roller assembly


95


, it is to be appreciated that the roller assembly


95


may be inserted into recesses formed within the side of the door


24


or in the spaces between the internal dividers


52


at the ends


31


of the door sections


40


. Additionally, the roller


95


may be directly inserted inside the hinge


51


.





FIG. 6

shows mounting of the roller assembly


95


at the hinge


51


inside an insert


98


. The roller assembly


95


includes a roller body


104


journaled to a roller shaft


105


. The roller body


104


includes a roller wheel


106


that extends radially outwardly from a collar


107


and may be integrally formed with the collar


107


. To restrict axial movement of the roller body


104


, relative to roller shaft


105


, the roller shaft


105


may be provided with an annular flange


108


at its outermost extremity and a radially upstanding annular rib


109


spaced axially inwardly therefrom, such that the roller body


104


rests between the projecting surfaces of the flange


108


and rib


109


. The annular rib


109


also prevents over insertion of the shaft


105


within the insert


102


by being sized larger than the corresponding opening within the insert


98


receiving roller shaft


105


. As shown in

FIG. 6

, the roller assembly


95


may be inserted externally of the end stile


60


, and the annular rib


109


may reside outside the exterior surface thereof. As shown, the roller shaft


105


is axially movable while the wheel


106


rotates about the shaft


105


within the roller track


27


, to accommodate variations in roller track


27


or the spacing between tracks


27


,


27


to either side of door


24


at different locations.




To reduce noise generated by the roller assemblies


95


, a liner, generally indicated by the numeral


110


, preferably made of polymeric material, may be inserted within the roller track


27


and may further wrap around the track surfaces and extend to partially cover the end stiles


60


of the door


24


as best seen in FIG.


6


. In this way, the sound from the contact between roller wheel


106


and roller track


27


is first attenuated by eliminating contact between the roller wheel


106


and roller track


27


and further by encapsulating the roller assembly


95


to isolate the sound. By overlapping the end stiles


60


of door


24


, liner


110


further prevents entry of fingers and other foreign objects at the sides of the door


24


, while providing a weather seal and assisting in stabilizing the door.




As best shown in

FIG. 6

, the liner


110


generally includes an insert portion fitting within the roller track


27


, a cover portion bridging the space between roller track


27


, door


24


, and a sealing portion overlying the stiles


60


. The first portion or insert portion


111


is sized to fit within the roller track


27


and has a substantially C-shaped cross-section for receiving the roller


104


and conforming to the roller track


27


. In the embodiment shown, the metal roller track


27


is not symmetrical, and has an outer track flange


112


and an inner track flange


113


. Since, as shown, the roller wheel


106


is substantially smaller than the space between the flanges


112


,


113


of roller track


27


, the liner


110


is provided with a spacer


114


extending outwardly from the generally C-shaped insert portion


111


to contact the interior surface


115


of the flange


112


. In this way, the C-shaped insert member


111


may be made to more closely conform to the dimensions of a particular roller wheel


106


. Otherwise, the insert


111


generally conforms to the surfaces of the track


27


and wraps around the ends


116


,


117


of the track flanges


112


,


113


.




Front and rear planar cover portions


118


extend from track flanges


112


,


113


, respectively, toward door


24


and are spaced a distance therefrom so as not to intrude upon the operation of the door


24


. Coverage of this area prevents foreign objects from intruding upon the function of the door


24


and constitutes a pinch guard for persons working on or in proximity to the door


24


when it is opening or closing.




Vertical seal portion, generally indicated by the numeral


119


, preferably includes front and rear flanges


120


and


121


, respectively, that extend inwardly from the cover portions


118


and


118


′, respectively, to substantially overlie stile


60


of the door


24


. The flanges


120


,


121


taper inwardly toward the door and preferably contact the front and rear surfaces


91


and


92


, respectively, of the end stile


60


. The front flange


120


serves primarily as a weather seal, while the rear flange


121


constitutes a finger shield.




As shown in

FIGS. 1

,


2


and


9


, the liner


110


generally extends the entire length of vertical track sections


28


of roller track


27


. The rear flange


121


, however, does not extend the full height of vertical track section


28


and is stopped short of the top of vertical track section


28


near transition track section


30


. This allows the door sections


40


to bend or otherwise freely move inwardly as they move from the vertical closed position to the horizontal open position. If desired, the transition track sections


30


and horizontal track sections


29


may be provided with the insert portion of liner


110


for purposes of abating noise.




When it is desired to design a door system


20


for utilization in an environment having minimal overhead clearance it is possible to employ a pivoting operator, generally indicated by the numeral


125


, which has the capability of effecting final closing and locking of a door


24


. Such an operator is described in Applicant's Assignee's application Ser. No. 09/081,419, now U.S. Pat. No. 6,112,799. The operator


125


may be installed and in the locked position for shipping as seen in FIG.


2


.




In the instance of use of a pivotal operator


125


, the uppermost section


41


of the door


24


may be provided with a pivoting roller, generally indicated by the numeral


130


, instead of a conventional fixed roller. Pivoting roller


130


has an arm


131


which in turn is rotatably mounted to the top door section


41


. As best seen in

FIG. 8

, this roller assembly


130


may be attached directly to the end


93


of cladding


80


by a milford pin


132


about which arm


131


may rotate. The arm


131


mounts a shaft


133


on which a roller wheel


134


is freely rotatably mounted. The roller wheel


134


of pivoting roller


130


follows the track


27


as door


24


moves between the open and closed positions. When in the closed position, with the door sections


40


in generally vertical alignment, the pivotal roller


130


rests within a transition track section


30


of the roller track


27


and has the arm


131


oriented in a substantially horizontal direction or generally perpendicular to the door section


41


. As the door


24


is initially opened to the position indicated as


41


′ in

FIG. 8

, the arm


131


of roller


130


pivots to assume a configuration substantially in planar alignment with door section


41


. Thus, the arm


131


of pivotal roller


130


is of such a length and positioned so shaft


133


of the roller


130


is located upwardly of the top of the door


24


.




To ensure the rotation of the arm


131


to the aligned position


41


′ during initial opening of the door the roller arm


131


may be spring biased toward the vertical, aligned position. To this end, a torsion spring


135


is coiled about milford pin


132


and has a first leg


136


attached to end


93


of cladding


80


and a second leg affixed below arm


131


or shaft


133


. It is to be appreciated that configured as described, the operator


125


, horizontal track sections


29


and door


24


all operate at or below the top of the header frame


23


such that no headroom clearance is required above header frame


23


. The arm


131


and roller


134


remain in alignment as the roller


134


of panel


41


moves from the transition track section


30


into the horizontal track section


29


indicated as position


41


″ and subsequently to the horizontal orientation of panel


41


indicated as position


41


′″ in FIG.


8


. Thus, with the pivoting roller


130


, the top of the top door section


41


never projects above the horizontal track section


29


.




The door system


20


may be readily modified to provide wind-resistant characteristics by incorporating the teachings of applicants' assignees' U.S. application Ser. No. 09/081,419, now U.S. Pat. No. 6,112,799, which is incorporated herein by reference. An exemplary form of modified roller mounting to embody such wind-resistant characteristics is generally indicated by the numeral


140


in

FIGS. 9 and 10

. As shown, a reinforcing member


141


is inserted within the double loop


70


of hinges


51


and extends substantially the entire width of the panels


40


of the door


24


. The reinforcing member


141


has a circumferential indented rib


142


located proximate each end thereof, one of which is shown in

FIGS. 9 and 10

.




The reinforcing member


141


receives a roller assembly, generally indicated by the numeral


145


. The roller assembly includes a roller shaft


146


and a roller wheel


147


and related structure which may be substantially according to the roller assembly


95


. Roller assembly


145


differs from roller assembly


95


in that the roller shaft


146


has an annular groove


148


which extends a distance axially thereof.




In conjunction with roller mounting


140


, the vertical track sections


28


of roller tracks


27


, which are normally substantially vertical and parallel to the ends to the end


93


of cladding


80


, except for being slightly outwardly inclined from bottom to top to seat door


24


at closure, are also angled outwardly at a small oblique angle in accordance with the aforesaid U.S. patent application Ser. No. 09/081,419 filed. Placement of the vertical track sections


28


so angled contemplates the upper extremities being closest to the door


24


, the lower extremities of track sections


28


being the greatest distance from the door


24


and intermediate locations on track sections


28


being downwardly at progressively greater distances from the door.




It will be appreciated that the rib


142


and groove


148


are located relative to the track sections


28


such that each roller


147


is in axial pressure engagement with an inner retaining leg


149


of track


28


or the overlying liner


110


when the door is in the closed vertical position. This results from rib


142


engaging the axially inner end


150


of groove


148


just prior to the door


24


reaching the closed position. The rib


142


is variously positioned in groove


148


displaced from inner end


150


of groove


148


during opening and closing of the door. Thus, when door


24


is in the closed position the roller assembly


145


and reinforcing members between each of the panels


40


are tension-loaded to resist buckling of the panels under applied wind and pressure forces.




An upward acting insulated or uninsulated sectional pan door system embodying the concepts of the present invention is generally indicated by the numeral


220


in

FIG. 11

of the drawings. The door system


220


is positioned and mounted for opening and closing movement in a building or trailer by a peripheral door frame, generally indicated by the numeral


221


. The frame


221


consists of a pair of spaced vertical track framers


222


,


222


that, as seen in

FIG. 11

, are generally parallel and extend vertically upwardly relative to a supporting surface such as floor or the bed of a trailer (not shown). The vertical track framers


222


,


222


are spaced and joined proximate their vertical upper extremity by a header framer


223


to thereby define the generally inverted U-shaped frame


221


for mounting a door, generally indicated by the numeral


224


. The frame


221


may be constructed of metal or other relatively high-strength, rigid material for purposes of reinforcement, attachment to a building or vehicle, and facilitating the attachment of elements involved in supporting and controlling the door


224


.




The header framer


223


may advantageously mount a counterbalance system, generally indicated by the numeral


225


, that interacts with the door


224


to facilitate raising and lowering the door


224


in a manner well known to persons skilled in the art. The counterbalance system


225


may be in accordance with the characteristics of the counterbalance system described hereinabove in conjunction with the counterbalance system


25


. As seen in

FIGS. 11 and 12

, flag angles


226


,


226


are provided to partially support roller tracks, generally indicated by the numerals


227


,


227


, which are positioned to either side of the door


224


. Each of the roller tracks


227


,


227


includes a substantially vertical track section


228


formed in vertical track framers


222


,


222


, a substantially horizontal track section


229


and a transition track section


230


interposed therebetween. The roller tracks


227


,


227


in a known manner thus support and direct travel of the door


224


in moving from the closed vertical position depicted in

FIG. 11

associated with vertical track sections


228


,


228


of roller tracks


227


,


227


through transition track sections


230


,


230


to the open, horizontal position associated with horizontal track sections


229


,


229


seen in FIG.


11


. The ends of horizontal track sections


229


,


229


displaced from the door


224


are joined and supported by a back bar


231


attached directly or indirectly to the ceiling or walls of a structure in which the door system


220


is installed. It will be appreciated that the door system


220


of

FIG. 11

may be packaged for shipping with the back bar


231


and the horizontal track sections


229


,


229


disassembled and positioned in relation to the door


224


in the same manner as is depicted in

FIG. 1

of the drawings with respect to the door system


20


.




For exemplary purposes, an eight-panel sectional door


224


is shown in

FIG. 11

of the drawings; however, it will be appreciated that more or less panels may be employed in sectional doors of this type depending upon the height of the door opening and related considerations. As depicted, the door


224


has a plurality of panels or sections, generally indicated by the numeral


240


, including a first or top panel


241


, a second panel


242


, a third panel


243


, a fourth panel


244


, a fifth panel


245


, a sixth panel


246


, a seventh panel


247


and an eighth or bottom panel


248


. Each of the panels


240


has generally the same essential configuration. Thus, only a single panel, panel


245


will be discussed in detail for exemplary purposes.




As shown in

FIG. 13

, each of the panels


240


of pan door system


220


has as a primary structural member a facer, generally indicated by the numeral


250


, having a front surface


251


which may be essential planar and extend substantially the height and width of the panels


240


. The top and bottom of front surface


251


of facers


250


transcend into pivotal closure assemblies, generally indicated by the numeral


255


, that include a first hook member


256


and second hook member


257


at the top and bottom edges, respectively, of the facers


250


. The first and second hook members


256


,


257


are generally semicircular and are preferably formed of substantially the same radius such that the second hook member


257


at the bottom of panel


244


encompasses the first hook member


256


at the top of panel


245


as seen in FIG.


13


. The facer


250


may also have an offset


258


between the front surface


251


and the first hook member


256


at the top of the panels


240


. At the bottom of each of the panels


240


the facer


250


has a projecting nose


259


located between the front surface


251


and the second hook member


257


. In this respect, when adjacent panels


240


are in a planar orientation as when the door


224


is in a closed position the nose


269


abuts the offset


258


such that a flush front surface of facers


250


of adjacent panels


240


is formed at their juncture. This cooperative engagement of nose


259


and offset


258


also serves to prevent the transfer of moisture and air from the outside elements to the space interiorly of the door


224


.




If desired to reduce transmission of heat and cold through the door and/or to reduce noise, the panels


240


may be provided with an insulation layer, generally indicated by the numeral


260


. The insulation layer


260


includes a foam body


261


which may be any of the polyurethane or polystyrene foaming materials commonly employed in the insulation of garage doors and the like. The insulation layer


260


may also advantageously have a backer


262


which may be of a metallic foil or paperboard material which may serve to protect the foam


261


from excessive moisture absorption or damage if contacted by a foreign object. Insulation layer


260


is preferably sized so that a top edge


263


and a bottom edge


264


are not exposed from the back of the door. To this end, the top edge


263


extends within the interlaced first and second hook members


256


,


257


as seen in FIG.


13


. The bottom edge


264


of insulation layer


260


for each panel


240


is wedged against the second hook member


257


, as also seen in FIG.


13


. To ensure retention and enclosure of foam layer


261


at its bottom edge


264


, a projecting flap


265


of the backer


262


may extend over at least a portion of bottom edge


264


and engage the second hook member


257


of the pivotal closure assemblies


255


. Thus, the top and bottom edges


263


,


264


of insulation layer


260


are tucked under the pivotal closure assemblies


255


of facer


250


over substantially the entire lateral width of the panels


240


. As will be seen hereinafter, the lateral extremities of insulation layer


260


are also confined such that all four edges of the insulation layer


260


are shielded from exposure inwardly of the panels


240


.




While the panels


240


are interconnected substantially throughout their lateral extent solely by the pivotal closure assemblies


255


except for hinge areas at the ends thereof described hereinbelow, the door


224


may be provided with coupler elements, generally indicated by the numeral


270


in

FIGS. 11

,


13


and


14


. While a single coupler


270


is shown between each of adjacent panels


240


substantially medially of the lateral extent thereof, it is to be appreciated that additional coupler elements


270


could be employed at selected locations depending upon the width of the door


224


.




The coupler elements


270


are shown in the form of a clip


271


having a deformable double loop which bears some similarity to the double loop


70


of door system


20


described hereinabove. The clip


271


has a flat curved segment


272


which transcends into an inner semicircular segment


273


. The inner semicircular segment


273


is connected by a hairpin curve return


274


to an outer semicircular segment


275


which is positioned substantially equidistant from the inner semicircular segment


273


throughout its extent when adjacent door panels


240


are in planar alignment as seen in

FIGS. 13 and 14A

. Both the inner semicircular segment


273


and the outer semicircular segment


275


are centered about a pivot axis


276


which remains substantially fixed relative to panels


240


. The inner semicircular segment


273


and the outer semicircular segment


275


are spaced and configured such as to accommodate both first hook member


256


and second hook member


257


of the pivotal closure assemblies


255


when operatively juxtaposed. The coupler element


270


may be constructed of a selected sheet steel or a polymeric material of the type described above in conjunction with the body portions


50


of door system


20


.




The operation of the coupler elements


270


in relation to the pivotal closures assembles


255


of panels


240


during movement of sectional door


224


between the closed and open positions is been seen in

FIGS. 14A-14D

.

FIG. 14A

shows adjacent panels


40


in a planar position as would exist in the open or closed position of the door.

FIGS. 14B-14D

depict the angular inclination which takes place between adjacent panels


240


as the door transcends through transition track sections


230


joining the vertical track sections


228


and horizontal track sections


229


, with a maximum angular orientation between adjacent panels


240


for the small-radius transition track sections


230


being approximately 75-80 degrees as depicted in FIG.


14


D.




The coupler element


270


and the first and second hook members


256


,


257


are depicted in a normal, unstressed condition in the planar orientation of adjacent panels


240


as seen in FIG.


14


A. As an angle develops between adjacent panels


240


during movement of the door


224


the hairpin curve return


274


moves about the pivot axis


276


displacing the hairpin return curve


274


to the left and upwardly, as is progressively depicted in

FIGS. 14B-14D

. In the position of

FIG. 14B

the first hook member


256


and second hook member


257


begin to separate in the areas proximate to the offset


258


and the nose


259


, while a crescent-shaped gap opens between the outer semicircular segment


275


of clip


271


and the second hook member


257


of pivotal closure assembly


255


. The separation of the first and second hook members


256


,


257


and the size of the gap becomes progressively larger as the panels


240


move to the relative positions depicted in

FIGS. 14C and 14D

. As in the case of the hinge


51


of the door system


20


the stress relief is dispersed over a sufficient area of the clip


271


and hook members


256


,


257


such that the materials are not distorted beyond their flex memory whereby the return of the door from the position of

FIG. 14D

to that of

FIG. 14A

restores the original configuration of coupler elements


270


and pivotal closure assemblies


255


of panels


240


.




As in the case of the door system


20


, the door system


220


has the pivotal closure assemblies


255


and coupler elements


270


configured such that no external or internal pinch points are created which could entrap a person's fingers. More particularly, the first and second hook members


256


,


257


of pivotal closure assemblies


255


remain in sufficiently close proximity during the entire pivotal movement of adjacent panels


240


such that the maximum separation between the nose


259


and the first hook member


256


is at all times less than the maximum permissible separation specified by industry standards for a pinch-resistant configuration. Thus, the pivotal closure assemblies


255


throughout their length provide a pinch-resistant configuration. Further, since the movements of the components of the pivotal closure assembly


255


are essentially pivotal about the pivot axis


276


or by separation of hook members


256


,


257


, the coupler elements


270


function to stabilize the pivot axis


276


of the pivotal closure assemblies


255


about the pivot axis of the panel hinges described hereinbelow during operation and to assist in assembly of the door


224


.




The ends of the facers


250


of panels


240


are encased within end stiles, generally indicated by the numeral


280


. As seen in

FIGS. 15-19

and


23


the end stiles


280


are generally U-shaped members devised to receive the front surface


251


and the pivotal closure assemblies


255


of the facers


250


of panels


240


. The end stiles


280


are defined by a planar end


281


which spaces and joins a front flange


282


and a rear flange


283


. While the front flange


282


may be of a substantially lesser lateral extent than the rear flange


283


, as best seen in

FIG. 18

, the front flange


282


does laterally overlie front surface


251


of facer


250


to an extent (FIG.


23


). The rear flange


283


may extend inwardly of panel


240


to a greater extent than front flange


282


for strengthening purposes and other functions which will become apparent. The laterally inner extent of rear flange


283


displaced from the planar end


281


has an in-turned flap


284


which serves as a strengthening member and, in the case of insulated panels


240


, overlies the lateral extremities of insulation layer


60


as best seen in FIG.


18


. Thus, as previously indicated, the in-turned flap


284


in overlying the lateral extremities of insulation layer


260


completes the retention and shielding of all four edges of the insulation layer


260


from exposure inwardly of the panels


240


. While the in-turned flap


284


is shown inclined inwardly from rear flange


283


through an angle of approximately 10 to 15 degrees, it is to be appreciated that this configuration of flap


284


may also be employed with an uninsulated version of panels


240


. Alternatively, the in-turned flap


284


might be directed inwardly through an angle of approximately


90


degrees to repose in proximity to facer


250


to effect further strengthening of panels


240


at the location of end stiles


280


.




The pivotal interconnection between adjacent panels


240


is effected primarily by hinge assemblies, generally indicated by the numeral


290


. The hinge assemblies


290


are located at the end stiles


280


from which the main structural members are formed. At the bottom of each of the end stiles


280


is a lower hinge pin receiver, generally indicated by the numeral


291


. The lower hinge pin receiver


291


is formed as a planar extension


292


of the end


281


of end stile


280


. As best seen in

FIG. 16

, the planar extension


292


, which preferably extends a distance below the rear flange


283


of end stile


280


and has a hinge pin receiving bore


293


in alignment with end


281


of end stiles


280


. The hinge assemblies


290


have at the upper extremity of the end stiles


280


an upper hinge pin receiver, generally indicated by the numeral


295


, which is cooperatively positioned in relation to the lower hinge pin receiver


291


when the door


224


is assembled. The upper hinge pin receiver


295


is shown formed as a continuation of the rear flange


283


of end stile


280


and includes a projecting leg


296


extending toward the front flange


282


of end stile


280


. As shown the projecting leg


296


lies inside the planar end


281


, is substantially perpendicular to both the front and rear flanges


282


,


283


and extends from rear flange


283


into contact with front flange


282


. The extremity of projecting leg


296


adjacent to front flange


282


has a reverse bend


297


which merges into a standoff leg


298


that is disposed at an acute angle to projecting leg


297


and directed outwardly of projecting leg


296


and back toward rear flange


283


of end stile


280


. The standoff leg


298


transcends into a substantially cylindrical hinge pin receiving sleeve


299


which is offset from the projecting leg


296


and preferably located substantially medially between front flange


282


and rear flange


283


of end stile


280


.




The lower edge of the panels


240


also has an arcuate flange


300


which is involved in hinge assemblies


290


. The arcuate flange


300


, as best seen in

FIGS. 17

,


18


and


23


, is a continuations of the bottom of rear flange


283


of end stiles


280


which projects inwardly and upwardly from rear flange


283


from a distance approximately one-half the distance between front flange


282


and rear flange


283


. As shown, the arcuate flange


300


may be substantially a portion of a circle centered about the center of hinge pin receiving bore


293


at a slightly lager radius, such as to substantially parallel the hinge pin receiving bore


293


. The arcuate flange


300


preferably runs the entire lateral extent of the rear flange


283


of end stile




The hinged connection of the lower hinge pin receiver


291


and upper hinge pin receiver


295


of hinge assemblies


290


is affected by roller assemblies, generally indicated by the numeral


305


. As best seen in

FIGS. 15

,


19


and


22


, the roller assemblies


305


may be similar to the roller assembly


95


discussed hereinabove. The roller assembly


305


includes a roller body


306


journaled to a roller shaft


307


. The roller body


306


includes a roller wheel


308


that extends radially outwardly from a collar


309


and may be integrally formed with the collar


309


(FIG.


22


). To restrict axial movement of the roller body


306


relative roller shaft


307


, the roller shaft


307


may be provided with an annular flange


310


at its outermost extremity and a radially upstanding annular rib


311


based axially inwardly therefrom, such that the roller body


306


rests between the projecting surfaces of the flange


310


and the rib


311


.




As can be seen in

FIGS. 15

,


19


and


22


, the roller shaft


307


is inserted into the receiving bore


293


of the lower hinge pin receiver


291


and through the cylindrical hinge pin receiving sleeve


299


, whereby the roller shaft


307


serves as a hinge pin for the hinge assemblies


290


. The annular rib


311


also prevents over insertion of the roller shaft


307


within lower hinge pin receiver


291


by being sized larger than the hinge pin receiving bore


293


. The roller shaft


307


has a second or inward annular rib


312


proximate the end of roller shaft


307


opposite the roller body


306


. As shown the annular rib


311


and the second annular rib


312


are spaced a sufficient distance on roller shaft


307


such that the roller shaft


307


is axially moveable within the sleeve


299


to an extent necessary to accommodate variations in the roller tracks


27


or spacing between the tracks


27


,


27


to either side of the door


24


at different locations.




The roller assemblies


305


are easily assembled in that the shaft may be readily inserted through pin receiving bore


293


which is larger in size than the second annular rib


312


. Since the cylindrical sleeve


299


is not a continuous integral piece, it springs open to receive the second annular rib


312


and returns to its original configuration once the second annular rib


312


extends inwardly of sleeve


299


in the assembled position depicted in FIG.


19


. Withdrawal of the roller shaft


307


is precluded by the second annular rib


312


engaging the laterally inner edge of cylindrical sleeve


299


. It is to be appreciated that the second annular rib


312


could take the form of outwardly projected tabs or punchouts in the roller shaft


307


located at one or more spaced circumferential locations about the circumference of the roller shaft


307


to similarly permit insertion of shaft


307


in cylindrical sleeve


299


while retarding withdrawal therefrom which may provide a type of tensioning in the closed position of the door to resist wind loads in the manner described above.




Referring to

FIGS. 11

,


12


and


22


, the vertical track sections


228


may be provided with a liner generally indicated by the numeral


315


, which may be similar to the liner


110


discussed above. The liner


315


may similarly be made of a polymeric material to reduce noise generated by the roller assemblies


95


and to overlie the ends of the panels


224


. Thus, the liner


315


serves to prevent entry of fingers and foreign objects at the sides of the door


24


while providing a weather seal, a door stop and assisting in stabilizing the door


224


. As best seen in

FIG. 22

, the liner


315


includes an insert portion which is sized to fit within the roller track


27


and has a substantially C-shaped cross-section for receiving the roller wheels


308


while fitting within the roller track


227


. The roller track


227


has an outer track flange


317


and an inner track flange


318


. The liner


315


has a front cover portion


319


and a rear cover portion


320


which extend from the insert portion


316


toward door


224


and are spaced a distance therefrom such as not to intrude upon the operation of the door


224


. As previously indicated, coverage of this area prevents foreign objects from intruding upon the function of the door


224


and constitutes a pinch guard for persons working on or in proximity to the door


224


when it is opening or closing. The liner


315


differs from the liner


110


in that the outer track flange extends to overlie the front flange


282


of end stile


280


to form a door stop


321


. As seen in

FIG. 22

, the front cover portion


319


extends around stop


321


to form a planar stop surface


322


which is adapted to engage door panel


240


and particularly the front flange


282


of end stile


280


when the door is in the closed position.




The liner


15


preferably includes front and rear flanges


323


and


324


, respectively, which extend laterally inwardly from the front cover portion


319


and the rear cover portion


320


, respectively, to overlie the panels


240


. The flanges


323


and


324


taper inwardly toward the door with the front flange


323


preferably contacting the facer surface


251


of panels


240


. The front flange


323


serves primarily as a weather seal, while the rear flange


324


constitutes a finger shield between planar end


281


of end stile


280


and the roller tracks


227


. As in the case of liner


110


the liner


315


generally extends the length of vertical track sections


228


of roller track


227


. The rear flange


324


terminates short of the top of vertical track section


28


near transition section


330


as seen in

FIG. 12

to permit movement of the door into the transition track section


230


. If desired, the transition track sections


230


and horizontal track sections


229


may have the insert portion


316


of liner


315


for purposes of abating noise.




As in the case of door system


20


, the door system


220


may employ a pivoting operator, generally indicated by the numeral


325


in

FIG. 11

of the drawings. As indicated in conjunction with the door system


20


, the pivotal operator


325


has the capability of effecting final closing and locking of door


224


.




In the instance of use of a pivotal operator


325


, the uppermost section


241


of the door


224


may be provided with a pivoting roller, generally indicated by the numeral


330


, instead of a conventional fixed roller. As seen in

FIG. 12

, the pivoting roller


330


has a support arm


331


which may be a generally U-shaped member having an attachment leg


332


and a roller mounting leg


333


. The attachment leg is adapted to seat against the rear flange


283


of end stile


280


or a reinforcing plate


334


positioned thereon. Attachment leg


332


is secured in place on panel


241


by one or more sheet metal screws


335


or other appropriate fasteners. The roller mounting leg


333


carries a cylindrical sleeve


336


which may be integrally formed with roller mounting leg


333


and be configured similar to the cylindrical hinge pin receiving sleeve


299


of the upper hinge pin receiver


295


. In this manner the sleeve


336


may receive a roller assembly


337


which is configured and positioned in the same manner as roller assemblies


305


of the hinge assemblies


290


. The pivoting roller


330


preferably has the support arm


331


constructed of a relatively thin metal or plastic material to permit flexing in the bend area


338


which joins attachment leg


332


and the roller mounting leg


333


. Since the requisite flexing in bend area


338


may be achieved by employing a relatively thin material for support arm


331


, the roller mounting leg


333


may be provided with a strengthening embossment


339


.




The pivoting roller


330


is shown in its stressed condition in

FIG. 12

with the door


224


in the fully closed position. In such instance, the roller assembly


337


and roller mounting leg


333


have been angularly displaced outwardly from the normal position by the pivoting operator


325


engaging and forcing the top panel


241


to the closed position. Once opening of the door commences, the support arm


331


returns to its initial configuration with the cylindrical sleeve


336


in engagement with the stile


280


and thus substantially aligned with top panel


241


as depicted at the chain line position


330


′ in FIG.


12


. With the cylindrical sleeve


336


and roller assembly


337


thus in close proximity to the top panel


241


during movement of pivoting roller


330


in the horizontal track section


229


, the top of the door section


241


remains essentially aligned with the horizontal track section


229


so as to permit installation of the door system


220


in a low overhead environment.




The lower corners of the door


224


may be provided with a combined roller assembly and cable-securing device, generally indicated by the numeral


345


. Referring particularly to

FIGS. 20 and 21

, the combined roller assembly and cable-securing device


345


includes a roller assembly, generally indicated by the numeral


346


, which may have the same structure as the roller assemblies


305


. In particular, the roller assembly


305


includes a roller body


347


, a roller shaft


348


and the structural details thereof as described above. The roller shaft


348


is inserted in an aperture


349


in the planar end


281


of end stile


280


. The combined roller assembly and cable-securing device


345


also includes a cable bracket, generally indicated by the numeral


350


, which is interposed between the roller body


347


and the end


281


of end stile


280


.




The cable bracket


350


has a generally cylindrical collar


351


which receives the roller shaft


348


but is preferably of a sufficiently larger internal diameter


352


such as to remain spaced therefrom during operation of door


224


. The cable bracket


350


has an elongated projection


353


extending radially from the collar


351


which is attached to the end


281


of end stile


280


as by screws


354


or other appropriate fasteners. The collar


351


also has a groove


355


which is adapted to receive a standard cable C which has one end reeved about the collar


351


to form a loop C′ and secured by a cable clamp


356


and the other end operatively interrelated with the counterbalance system


225


. Thus, the loop C′ of cable C may attach to door


224


at an optimum position while permitting angular movement of the cable relative to groove


355


of cable bracket


350


as its position varies relative to the counterbalance system


225


. It will also be appreciated that the tension in cable C produced by counterbalance system


225


is transmitted to door


224


without imparting forces to the roller shaft


348


or roller body


347


of roller assembly


346


.




Thus, it should be evident that the upward acting sectional door disclosed herein carries out one or more of the objects of the present invention set forth above and otherwise constitutes an advantageous contribution to the art. As will be apparent to persons skilled in the art, modifications can be made to the preferred embodiments disclosed herein without departing from the spirit of the invention, the scope of the invention herein being limited solely by the scope of the attached claims.



Claims
  • 1. An upward acting sectional door comprising, a plurality of door panels pivotally attached to each other, each panel having a front surface and a rear surface spaced from each other by an internal structure, the internal structure defining a plurality of encapsulated spaces between the front and rear surfaces which provide a thermal break therebetween, wherein said panels are pivotally attached to each other by a flexible hinge member at an edge of said panels, said flexible hinge member including a double loop having an inner leg and an outer leg with said outer leg spaced from and substantially paralleling said inner leg and said flexible hinge member extending the entire lateral extent of said panels.
  • 2. The door of claim 1, wherein said internal structure includes a plurality of dividers located within the front and rear surfaces.
  • 3. The door of claim 2, wherein said dividers are configured in a honeycomb arrangement.
  • 4. The door of claim 2, wherein the dividers are intersecting horizontal and vertical surfaces.
  • 5. An upward acting sectional door comprising, a plurality of door panels pivotally attached to each other, each panel having a front surface and a rear surface spaced from each other by an internal structure, the internal structure defining a plurality of encapsulated spaces between the front and rear surfaces which provide a thermal break therebetween, and a recess formed in said rear surface of said panel and an end stile fitting over an end of said panel, said end stile including a tab releasably received within said recess.
  • 6. The door of claim 5, wherein said end stile includes a front flange, a rear flange, and an end extending between said front and rear flanges to define a generally U-shaped member having an open end sized to receive said front surface and said rear surface.
  • 7. The door of claim 6, wherein said rear flange does not extend the full height of said panel to permit relative rotation between adjacent of said plurality of door panels.
  • 8. The door of claim 6, wherein said end of said end stile has a top rounded extremity and a bottom rounded recess, whereby said top rounded extremity of one of said plurality of door panels pivotally interfits within said bottom rounded recess in an adjacent one of said plurality of door panels.
  • 9. The door of claim 6, wherein said end of said end stile has an opening adapted to receive a roller assembly.
  • 10. The door of claim 9, wherein said roller assembly includes a shaft extending through said opening.
  • 11. An upward acting sectional door comprising, a plurality of door panels pivotally attached to each other, each panel having a front surface and a rear surface spaced from each other by an internal structure, the internal structure defining a plurality of encapsulated spaces between the front and rear surfaces which provide a thermal break therebetween and a hinge pivotally connecting said plurality of door panels and a reinforcing member received within said hinge, said reinforcing member receiving a shaft of a roller assembly.
  • 12. An upward acting sectional door comprising, a plurality of door panels pivotally attached to each other, each panel having a front surface and a rear surface spaced from each other by an internal structure, the internal structure defining a plurality of encapsulated spaces between the front and rear surfaces which provide a thermal break therebetween and a cladding covering the front surface of said panels, wherein said cladding is releasably attached to said panels by a pair of hooks, the first hook extending from the top of said cladding and the second hook extending from a bottom of the cladding and said panels have a flexible hinge interacting with said first hook and said second hook.
  • 13. The door of claim 12, wherein said first hook and said second hook interengage and are maintained in operative pivotal relationship by said flexible hinge.
  • 14. The door of claim 12, wherein said flexible hinge is formed integrally with one of said panels and retained in operative relation with an adjacent of said panels by said cladding.
  • 15. A sectional door having a plurality of panels joined by a hinge, the hinge comprising, a flexible double loop member extending between adjacent panels, said flexible member defining a first axis and a second axis about which said sections pivot, wherein at least one of said axes is moveable relative to said panels during operation of the door such that stresses within the hinge caused by articulation of the panels are relieved by pivoting about said axes and movement of at least one of said first and second axes.
  • 16. The hinge of claim 15, wherein said hinge extends the entire lateral width of the door.
  • 17. A sectional door having a pair of opposed tracks for guiding door rollers between a closed position and an open position having a liner within the tracks comprising, an insert portion adapted to conform to the inner surface of the track for contacting the door rollers, a cover portion attached to the insert portion and bridging the space between the door and the tracks to prevent entry of foreign matter, and a sealing portion attached to the cover portion and extending to at least partially cover the door as a weather seal and to assist in stabilizing the door.
  • 18. The door of claim 17, wherein said sealing portion includes a pair of opposed flanges spaced from each other and defining a gap adapted to receive an end of the door.
  • 19. The door of claim 17, wherein at least one of said flanges contacts a surface of the door.
  • 20. The door of claim 18, wherein one of said flanges has a stop for engaging, and positioning the door in the closed position.
  • 21. A pre-packaged upwardly acting sectional door system comprising, a pair of spaced track framers spanned by a header, a pair of tracks associated with said track framers, a door having a plurality of panels pivotally joined by hinge members, roller assemblies on said door received in said tracks, a counterbalance system attached to said header and operatively engaging said door, and an operator mounted on said header operatively interconnected with said counterbalance system and positioned to maintain said door in a closed position relative to said header, said track framers, said tracks, said door, said rollers, said counterbalance system and said operator being operatively assembled for transport and installation.
  • 22. A pre-packaged, assembled upwardly acting sectional door system comprising, a pair of spaced track framers spanned by a header, a pair of tracks associated with said track framers, a door having a plurality of panels pivotally joined by hinge members, roller assemblies on said door received in said tracks, a counterbalance system attached to said header and operatively engaging said door, and an operator mounted on said header operatively interconnected with said counterbalance system and positioned to maintain said door in a closed position relative to said header and a motor pivotable between an operating position and a locked position, said motor being in a locked position adjacent the door.
  • 23. An upwardly acting sectional door system comprising, a plurality of sections including a top section, the sections being mounted between a pair of tracks, including horizontal track sections, which guide the door between a closed and an open position, a roller assembly, having an arm pivotally attached to said top section at one end thereof, a wheel rotatably attached to said arm at the other end thereof, wherein said wheel fits within said tracks causing said arm to pivot from a position at an angle to said top section when the door is in the closed position to a position above and substantially in planar alignment with said top panel when the door moves toward the open position, whereby said top section never projects above said horizontal track section to eliminate the need for overhead clearance.
  • 24. The roller assembly of claim 23, wherein the arm is biased to said position substantially aligned with said top panel.
  • 25. The roller assembly of claim 24, wherein said arm is biased by a spring interposed between said arm and said top section.
  • 26. The roller assembly of claim 24, wherein said arm is made of a unitary flexible material.
  • 27. A sectional door comprising, first and second adjacent panels, a flexible double loop member having an inner leg and an outer leg joined by a curve return extending between said adjacent panels and attached to said first and second adjacent panels, a first hook attached to one of said first and second adjacent panels and interposed between said inner leg and said outer leg, said return curve movable about an axis located substantially centrally of said flexible double loop member during a portion of the articulation of said first and second panels and said outer leg and said hook movable about said return curve during a portion of the articulation of said first and second panels.
  • 28. A sectional door according to claim 27 further comprising, a second hook attached to the other of said first and second panels and overlying a portion of said inner leg of said flexible double loop member.
  • 29. A sectional door according to claim 28, wherein said first hook and said second hook are in engagement during a portion of the articulation of said first and second panels.
  • 30. A sectional door according to claim 29, wherein said first hook and said second hook develop a crescent-shaped gap therebetween during a portion of the articulation of said first and second panels.
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