Door assembly

A door assembly is provided for use in proximity to door openings wherein there is a large amount of material handling vehicle traffic. The assembly includes a frame mounted within the door opening and having upright elongate side sections. Each section has an interior guideway with an elongate entry thereto. Within each section is a pair of guide members forming therebetween a gap aligned with the entry. A flexible door member is slidably mounted on the frame. Opposite marginal side segments of the door member extend through the entries and gaps into the section guideways. Each marginal segment is provided with a plurality of relatively spaced, vertically aligned follower elements normally impassable with respect to the gap. Upon an external force of at least a predetermined magnitude being exerted on an exposed surface of the door member while in a closed mode, the follower elements will exert a predetermined wedging force on the gap-forming portions of the guide members causing a change in the relative dimensions of the gaps and follower elements allowing the follower elements to pass through the gaps and effect at least partial disassembly of the door member from the frame. Each section is provided with an adjustable panel which may be selectively adjusted to an open position exposing the guideway thereby permitting the follower elements to be reassembled in the respective guideway.

The invention relates to a break-away type of door member which will become 
disassembled from a frame mounted in proximity to a door opening, when an 
external force above a predetermined magnitude is exerted on an exposed 
area of the door member. 
BACKGROUND OF THE INVENTION 
Door assemblies, when installed in proximity to door openings where there 
is high material-handling vehicle traffic, are frequently accidentally or 
carelessly struck by such vehicles when the opening is fully or partially 
closed. In order to compensate for these conditions, various prior door 
assemblies were developed wherein the door members thereof were of the 
breakaway type, that is to say the door member would be disassembled from 
the frame structure with a minimal amount of damage to various components 
of the assembly. An example of such a breakaway type of door assembly is 
disclosed in U.S. Pat. No. 5,058,651 dated Oct. 22, 1991; however, such 
patent fails to disclose a means whereby the door 10, 110, if disassembled 
from the guides 14, 114, may be readily reassembled with such guides 
without difficult maneuvering or substantial portions of the assembly and 
door frame work being dismantled. Such maneuvering or dismantling is a 
costly, time-consuming operation and normally requires an inordinate 
amount of manual labor. 
Where such types of prior door assemblies are utilized in proximity to an 
outside door opening, it is difficult to interfit the door member and 
associated frame in such a way as to avoid leaks or annoying drafts around 
the door area. In addition to such annoying drafts, where the door member 
of the prior assembly is of a flexible material, serious and distracting 
vibration noises develop particularly when the door member is buffeted by 
wind gusts or driving rain or snow causing the door member material to 
flutter. 
SUMMARY OF THE INVENTION 
Thus, an improved door assembly is provided which is of simple, yet sturdy 
construction; may be readily installed; is easily serviced and maintained; 
and is attractive in appearance. Furthermore, the improved door assembly 
may be utilized for door openings varying in size and shape over a wide 
range and may be readily secured in a closed mode when desired. 
Additional virtues and advantages inherent in the improved door assembly 
will become apparent from the description, accompanying drawings and 
appended claims. 
In accordance with one embodiment of the invention, a door assembly is 
provided which is particularly suitable for use in proximity to door 
openings provided in commercial and manufacturing facilities wherein there 
is high material handling vehicle traffic. Such openings are normally 
located at loading docks, or in interior partition walls separating or 
segregating various areas within a plant or warehouse. The improved 
assembly includes a frame disposed in proximity to the designated door 
opening, and a flexible door member slidably mounted within the frame for 
movement between open and closed modes. The frame is provided with a pair 
of side sections disposed on opposite sides of the door opening. Each side 
section includes an upright housing extending substantially the full 
height of the door opening and having an elongate interior guideway. The 
housing is provided with an elongate entry communicating with the adjacent 
guideway and extending substantially the full height thereof. Disposed 
within each housing are guide members which cooperate with one another to 
form a narrow gap which is aligned with the entry. 
When the door member is in assembled relation with the frame, marginal 
segments of the door member extend through the gaps and terminate within 
the housing guideways. Each marginal segment is provided with a plurality 
of longitudinally spaced, vertically aligned follower elements. The 
follower elements are impassable with respect to an adjacent gap because 
of the normal relative dimensions of the gap and follower elements. Where, 
however, an external force of at least a predetermined magnitude is 
exerted on an exposed surface of the door member, the follower elements 
will exert a wedging force on the gap-forming portions of the guide 
members causing a change in the relative dimensions of the gap and 
follower elements allowing the latter to pass through the gap and effect 
at least partial disassembly of the door member from the frame. 
The housing of each frame side section is provided with a hinged panel 
which may be selectively adjusted to an open position exposing 
substantially the full height of the interior guideway. While the housing 
panel is in the open position, the marginal segment and associated 
follower elements may be readily reassembled in the guideway or serviced 
as the case may be. A locking means is provided for selectively securing 
the door member in a closed mode.

DESCRIPTION 
Referring now to the drawings and more particularly to FIG. 1, one 
embodiment of the improved door assembly 10 is shown adjacent to a door 
opening D provided in a commercial building, plant, warehouse or the like. 
The door opening D may be formed in an outside wall, such as at a loading 
dock or in an interior wall. The door assembly 10 includes a frame F 
having a pair of upright side sections 11, disposed on opposite sides of 
the opening D, and a header 12 disposed above the opening D and 
interconnecting the upper ends of the side sections. A door member 13 is 
slidably mounted on the frame F for selective movement between open and 
closed modes. The door member may be formed of a flexible fabric-like 
material which is durable, water resistant, thermal insulative and capable 
of withstanding substantial impact without tearing or rupturing. The door 
member should remain flexible when subjected to extreme climatic 
conditions. 
Each side section 11 is preferably of similar construction and, as seen in 
FIGS. 1 and 3, includes an upright housing 14, which extends substantially 
the full height of the door opening and is provided with an elongate 
interior guideway G. The side of the housing facing the other side section 
is provided with an entry E in communication with the guideway. A panel 
11A of the housing defining at least in part the entry E is hinged at 11B 
so that it may be selectively adjusted to a fully open position, shown in 
phantom lines in FIG. 3. When in such position substantially the entire 
length of the guideway G, as well as the remainder of the housing interior 
are exposed. The importance of this feature will be discussed more fully 
hereinafter. 
Disposed within each housing interior are guide members 15 and 16 having 
portions 15a, 16a thereof which cooperate with one another to form a 
narrow gap K normally having a first dimension. The gap is in registered 
or aligned relation with the entry E. Each guide member may have an 
inwardly flared portion 15b, 16b which defines in part a surface of 
guideway G. 
As seen in FIG. 3, guide member 15 is hinged at 15c to an interior surface 
portion of housing 14 and is biased by spring 17 so that portion 15a will 
cooperate with portion 16a to form the gap K. If desired, guide member 15 
may be fixed to the housing interior in which case guide member 16 would 
be slidably mounted on the interior surface of panel 11A and be biased by 
a spring, not shown, towards the other guide member 15. 
Door member 13 normally has a substantially rectangular configuration which 
is of such size that, when the member is in the closed mode, the door 
opening D will be completely covered by the member. The side marginal 
segments 13A of the door member, when the latter is properly assembled 
with the frame, extend laterally through the corresponding gaps K and 
terminate within the respective housing interior, see FIG. 3. Each 
marginal segment 13A is provided with a plurality of longitudinally 
spaced, vertically aligned follower elements 18. The elements may be of 
sectional design with each section having a semi-spherical configuration 
or various other profile configurations which cause the elements to be 
impassable with respect to the gaps K when each of the latter has a first 
dimension. The elements 18 may be of a suitable hard plastic material 
which will readily slide over the exposed surfaces of guide member 
portions 15b, 16b when the door member moves between the open and closed 
modes. On the other hand, the elements 18 may be formed of a compressible 
material which will compress under a predetermined pressure produced by an 
external force of a wind gust or a vehicle impacting on the exposed 
surface of the member 13 when in a closed mode. Where the follower 
elements are of a compressible material, both guide members 15, 16 may be 
fixed within each housing. 
In the illustrated embodiment, the follower elements 18 are of a suitable 
hard material and the exterior configuration of each element is such that, 
when the element exerts a predetermined wedging force against the guide 
member portions 15b, 16b, a camming action occurs causing the guide member 
15 to overcome the bias of spring 17 enlarging gap K to a second 
dimension, shown in phantom lines in FIG. 3, allowing the follower element 
to pass through the enlarged gap whereupon the door member is at least 
partially disassembled from the frame side sections 11. 
The portion of the marginal segment normally disposed within gap K may be 
provided with wear strips (not shown) which would serve a dual function; 
namely, to reduce material wear and to minimize sliding friction between 
the guide members and the door member. 
As seen in FIGS. 2 and 3, the follower elements 18 are set in from each 
side edge 13B of the door member so that, when the member is assembled 
with the side sections, the edge of the marginal segment is disposed 
within the guideway G a substantial distance from the gap whereupon the 
possibility of leaks or drafts occurring around the periphery of the 
member 13 is virtually eliminated. 
The upper marginal edge of the door member 13 may be affixed to an elongate 
drum-like member 21 which is mounted for rotation about a transversely 
extending horizontally disposed shaft 22. The drum-like member 21 is 
disposed within header 12. At least one end of shaft 22 may be power 
driven by a reversible electric motor M through a chain drive C, see FIG. 
4. The actuation of the motor and the direction of rotation thereof are 
manually regulated by remote controls, not shown, located proximate the 
door opening D. 
The lower marginal edge of door member 13 is attached to an inflexible, 
elongate bar 23 which substantially spans the distance between the frame 
side sections, see FIG. 1. The underside of bar 23 may be provided with 
suitable weather stripping S which resiliently engages the floor of the 
door opening when the door member is in the fully closed mode. 
A counter-balancing unit 24 may be provided within each side section 
housing, only one being shown in FIG. 1, which assists in moving the door 
member 13 between the open and closed modes. The unit 24 includes a 
plurality of individual weights W which may be arranged in stacked 
relation. The number of weights in the stack determines the extent of the 
counter-balancing effect desired. As seen in FIG. 1 a sheave 25 may be 
attached to the underside of the stack of weights. A second sheave 26 is 
fixedly attached to a bottom section of the housing. A flexible cable 27 
engages the sheaves and has one end 27a connected to one end of bar 23 and 
the other end 27b connected to one end of a coil spring 28. The other end 
of the spring is fixedly connected to the bottom panel of the housing. The 
length and strength of spring 28 are predetermined so that the door member 
is continually under tension thus, maintaining the exposed portion of the 
door member in a taut condition. By maintaining the exposed door member 
portion in a taut condition, the problem of flutter of the material 
forming the door member is substantially avoided and vibration noises 
attributed thereto are eliminated or significantly diminished and the 
overall appearance of the door member is enhanced. 
The opposite ends of bar 23 may be provided with lock components (e.g. 
sliding bolt) which coact with complemental lock components provided at 
the bottom section of each housing and securely lock the door member 13 in 
a fully closed mode. One of the lock components at each housing may be 
key-actuated. 
When the marginal segments 13A of the door member has become disassembled 
from the side sections, the hinged panel 11A of each housing is manually 
adjusted to the open, or inoperative, position, see phantom lines in FIG. 
3. When the panel 11A is in such a position, the full height of guideway G 
is uncovered, whereupon the portions 15a, 15b of guide member 15 are 
exposed enabling the follower elements 18 along each marginal segment to 
be realigned with the guide member portion 15a. At the same time any 
adjustment or servicing of the counter-balancing and tensioning components 
may be readily attended to. Thus, once the reassembling and/or servicing 
operations have been completed, the housing panel 11A is once again 
adjusted to its normal closed position, as shown in full lines in FIG. 3. 
Suitable fasteners, not shown, may be provided for retaining the hinged 
panel 11A in a closed position. By reason of the housing panel 11A being 
hinged, the reassembling and/or servicing of the door assembly is greatly 
simplified and may be readily accomplished in a facile and expeditious 
manner. 
While the improved door assembly 10 has heretofore being described with the 
header 12 disposed above the door opening, in some instances it may be 
located in a trench, not shown, provided in the floor. In such an 
arrangement, the drum-like member 21 would be disposed beneath the floor 
level and the door member 13 would be pulled upwardly to effect closing of 
the door opening. In another version of the improved door assembly, the 
door member in lieu of being attached to the drum-like member 21 may move 
upwardly in an unrolled condition within an upright narrow pocket which 
may be mounted vertically above the door opening. In this latter 
arrangement, substantial vertical head-room would be required above the 
door opening to accommodate the narrow pocket. 
Referring now to FIGS. 5-8 a second embodiment of an improved assembly 110 
is shown. Components of assembly 110 which are comparable to components of 
assembly 10 will have similar identifying numbers but in the 100 series. 
Assembly 110 embodies a frame FF, see FIG. 7, having a pair of upright side 
sections 111 fixedly mounted on opposite sides of the door opening D and 
extending substantially the full height of the door opening. Each side 
section is preferably of like configuration and includes a channel-shaped 
housing 114 having an open side, see FIG. 7, facing the other side section 
and defining an entry EE extending the full length of the housing. 
Positioned within each entry is a pair of upright, substantially parallel 
guide members 115, 116 which form therebetween a gap KK of a predetermined 
fixed dimension, which is aligned with the entry EE. Guide member 116 is 
secured to an access panel 114a of a housing 114 forming one leg of the 
channel-shaped housing. Panel 114a may be manually removed from the 
remainder 114b of the housing, as will be described more fully hereinafter 
when the door assembly is to be serviced. 
Frame FF includes a header 112 which is disposed above the door opening and 
interconnects the upper end portions of the side sections 111. Rotatably 
mounted within header 112 is an elongate drum or spool 121 on the 
periphery of which the upper edge portion of a flexible door member 113 is 
secured. Depending upon the direction of rotation of the drum, the door 
member 113 will move to either an open mode or a closed mode relative to 
the door opening. As seen in FIG. 5, the drum may be provided with a 
balance spring 150, preferably of a coil configuration, having an axis 
thereof aligned with the axis of rotation of the drum itself. The size and 
tension of spring 150 are predetermined so that raising and lowering of 
the door member 113 may be readily accomplished with a small amount of 
manual effort. 
As seen in FIGS. 5 and 8, rotation of drum 121 may be accomplished by a 
chain and sprocket wheel assembly 151 which is mounted on the upper end 
portion of one of the side sections 111. As seen in FIG. 8, a first 
sprocket wheel 152 is keyed to one end of the drum shaft 121a. The shaft 
ends are supported by brackets 153, see FIGS. 6 and 8; each bracket being 
secured to the upper portion of the side section. Mounted in vertical 
alignment beneath sprocket wheel 152 is a smaller diameter second sprocket 
wheel 154 which is keyed to a stub axle 155. The wheels 152 and 154 are 
interconnected by a first continuous chain section 156. Also keyed to the 
stub axle is a third sprocket wheel 157 which is engaged by a second 
continuous chain section 158. The chain section 158 depends from sprocket 
wheel 157. The lower end of chain section 158 does not require further 
support, but may, if desired be restrained from lateral movement, e.g., 
swinging, by means such as a sprocket, pulley, or channel, not shown, the 
latter means being mounted at or near the bottom of the side section. The 
vertical portions of chain section 158 are exposed and may be readily 
grasped to effect rotation of the drum and movement of the door member 113 
to either the open or closed mode. Access to the chain vertical portions 
may for reasons of security be restricted to one side (e.g. inside) of the 
door member 113. A suitable lock mechanism, not shown, may be utilized for 
locking one chain vertical portion to a fixed portion of the adjacent 
housing 114. 
Like door member 13, member 113 has mounted on the side marginal segments 
113A a plurality of vertically spaced follower elements 118. Each element 
118 may have a shape as seen in FIGS. 12, 13. In the illustrated 
embodiment, element 118 is a substantially U-shaped clip with one leg 118a 
thereof provided with an outwardly extending protuberance 118b. The 
opposite leg 118c of the clip is substantially flat, see FIG. 13. The 
spacing between the legs is sized to accommodate the material thickness of 
the marginal segment 13A of the door member 113. The marginal segment of 
the door member 113 is provided with a plurality of vertically spaced 
slots Z, one for each follower element. The slot is shaped to accommodate 
a bail section 118d of the element 118. The slots are set in from the 
marginal edge 113B of the door member so that when the door member is 
assembled on the frame the edge will be disposed well within the interior 
guideway GG of the frame channel-shaped housing 114. Preferably, a 
reinforcing patch 113C is mounted on one or both sides of door member 113 
to reinforce the area around the slot Z and the follower element 118. See 
FIGS. 12 and 13. 
Each follower element is preferably formed of strong yet distortable 
plastic material. The normal overall dimension of the follower element 
measured perpendicular to leg 118c and through the zenith of protuberance 
118b is greater than the spacing between the stationary guide members 115, 
116. Thus, in order for the follower elements 118 to pass between the 
guide members, the protuberances 118b of the follower elements must be 
distorted sufficiently so as to reduce the normal overall dimension. Such 
distortion occurs only when a wedging force above a predetermined amount 
is exerted on the guide members by the follower element protuberances. 
This will occur before the door member and frame are structurally damaged. 
As seen in FIGS. 9-11, the bottom portion of the door member is provided 
with an elongated bar 123 which spans the distance between the side 
section housings 114. Projecting endwise from opposite ends of the bar are 
tab-like brackets 160. Depending from each bracket 160 is a pair of 
tongues 160a between which is pivotally connected a lock component 161, 
see FIG. 9. The lock component 161 is provided with a peripheral notch N 
which is adapted to lockingly accommodate a stationary complemental lock 
component 162, mounted on the bottom portion of the side section, see FIG. 
9, when the door member assumes its closed mode. Lock component 161 is 
biased to assume a locking position by a spring-loaded release mechanism 
163 which is adjustably mounted on bar 123. 
Mechanism 163 includes a pair of elongate cables 164, 165, each having a 
corresponding end 164a, 165a thereof pivotally connected to an actuating 
arm 166, the latter having its midlength 166a mounted on the bar 123 for 
pivoting about axis X, see FIG. 9. The opposite corresponding ends 164b, 
165b of the cables are pivotally connected to the adjacent lock component 
161. Each cable is provided with a collar 164c, 165c which is affixed to 
the cable and moves therewith. Spaced inwardly from the corresponding 
cable collar and affixed to the bar 123 is a slotted bracket 167 through 
which a segment 164d, 165d of the cable is adapted to slidably extend. 
Encompassing a portion of each cable disposed between the respective 
collar 164e, 165e and bracket 167 is a bias spring 168 which exerts the 
biasing force on the adjacent lock component 161. 
A crank handle 170 is connected to actuating arm 166 for pivoting same 
about the arm axis X. When handle 170 is rotated in a clockwise direction 
about axis X the actuating arm will move in a like direction from position 
I (phantom lines, FIG. 9) to position II causing the cable ends 164b, 165b 
to be retracted and moving the lock components 161 to release positions 
with respect to the stationary lock components 162. The lock components 
161 in the release position are shown in full lines and in the locked 
position in phantom lines in FIG. 9. 
As seen in FIGS. 9 and 11, each bracket 160 is mounted on the adjacent end 
portion of the bar 123 so as to pivot about a fixed axis Q. The bracket 
has a recess 172 which is engaged by a ball detent 174 to releasably 
retain the bracket in its operative position. Upon impact the bracket 
rotates about axis Q to release the door. By reason of the pivotal 
mounting of the brackets 160, the latter may readily slide past the guide 
members formed in the side sections when the door member is subjected to 
an exterior force above a predetermined amount due to impact of a vehicle 
or the like without damaging the door member or side sections. In the 
alternative, the bracket 160 may be formed of a resilient material thus 
eliminating the need for the pivot mechanism including detent 174. 
As aforementioned, the panel 114a of housing 114 of each side section may 
be manually removed from the remainder of the housing when the marginal 
segments 113A of the door member 113 are to be re-assembled with the side 
sections 111 or the assembly is to be serviced. To permit such removal, 
the upper and lower portions 116a and 116b of the guide member 116, 
respectively, are engaged by vertically aligned stationary pintles P.sub.1 
and P.sub.2, see FIG. 14. Pintle P.sub.1 is disposed above pintle P.sub.2 
and has a greater longitudinal length than pintle P.sub.2 and is fixedly 
secured to a mounting bracket 114c provided on the portion 114b of the 
housing 114. The shorter pintle P.sub.2 is affixed to a bottom panel 114d 
of the housing. Each pintle has a cylindrical configuration and an outside 
diameter dimension relative to the inside diameter of the open ends of 
guide member 116 so as to provide a sliding rotational fit between the 
panel 114a and the pintles. Thus, to remove housing panel 114a from the 
remaining portion 114b of the housing, panel 114a is manually pivoted 
outwardly away from portion 114b about the pintles P.sub.1, P.sub.2 as an 
axis and then panel 114a is raised or lifted relative to the pintles until 
the lower end of the guide member 116 is above the top of lower pintle 
P.sub.2. When this occurs, the lower end of panel 114a may be laterally 
offset a slight amount so to clear the lower pintle. There is enough 
tolerance between the upper pintle P.sub.1 and the end opening of guide 
member 116 to permit the aforementioned lateral offsetting. 
A suitable handle, not shown, may be provided on the exterior of housing 
panel 114a to facilitate manual manipulation thereof. Furthermore, 
suitable locking means may be provided on panel 114a for retaining same in 
an assembled relation with housing portion 114b. 
Thus, a simple, yet sturdy and attractive door assembly has been disclosed 
which may be readily serviced and maintained and when necessary enables 
the door member to be readily and easily reassembled with the frame.