[0001] The present invention relates to garage doors, especially, but not exclusively, of
the so-called "up-and-over" type which are widely used for domestic garages.
[0002] A large majority of such doors as are now available are constructed in the form of
a generally rectangular frame into which one or more panels are secured. The frame
is of metal and, although in some cases timber panels are used, a high proportion
of these doors use panels fashioned from pressed steel sheet. This form of construction
has the important advantage that it is readily adapted to the production of doors
of a range of different sizes from a minimum number of different components. However
the large-scale manufacture of doors of this type is a major consumer of resourses
and/or manpower in the securing together of the components of the doors.
[0003] One approach to the production of doors of this type is to secure the metal panels
to each other and to the door frame by spot-welding at intervals along the abutting
surfaces. However, in a typical single door constructed from, say, five narrow panels
and wherein the welds are spaced at intervals of the order of 8 to 10 cm, there are
as many as 200 spot welds required. Since welding in this way not only entails heating
the components in the region of the welds to a suitably high temperature but also
then requires a water-based cooling system to remove the heat, this method of constructing
metal-panelled garage doors consumes large quantities of energy. Unless the welding
operation is highly automated, the manpower requirement is also high.
[0004] An alternative prior approach has been to assemble the doors by securing the components
together using rivets, studs or similar fasteners. However, as with welding, it is
necessary to make the connections at relatively close spacing. Thus assembling doors
by riveting in this way requires large numbers of rivets and therefore contributes
significantly to the costs of large-scale production.
[0005] It is therefore an object of the present invention to provide an improved garage
door, which can be produced with a considerable saving of consumable resources of
energy and/or materials as compared with existing doors.
[0006] The improved garage door according to the invention comprises a generally rectangular
metal frame and one or more metal panels located within the frame, the panels being
secured to each other and/or to the frame by a multiplicity of connections at intervals
along the abutting lengths of the panels or frame, each connection comprising a localised
non-piercing stretching of the two metal components into a laterally-larged protrusion
which holds the two components together.
[0007] The door is of the type having a generally regular metal frame having one or more
metal panels located in the frame. Doors of this general type are well known. The
frame in the present case is preferably constructed from steel sections welded and/or
rivetted together at the corners but by virtue of the form of connections defined
above, the need for welding or rivetting in other constructional connections in the
door structure may be avoided. The invention is applicable to any door having a metal
frame and one or more metal panels but is of particular merit when applied to a metal-panelled
door of the type which is a subject of co-pending EuropeanPatent Application No. 91303686.
9, filed 24th April 1991.
[0008] The metal panel or panels of the door of the present invention may be mounted in
the frame with their longer axes vertical or horizontal (relative to the door in its
closed position). In general, panels of this type have flanges running continuously
along at least the longer sides of the panels and it is these flanges by which adjacent
panels are usually secured together and to the adjacent door frame. In the case of
the present invention, it is preferably such side-flanges on the door panels which
are connected together and/or to the door frame by the form of connections defined
above.
[0009] Connections of this type are known in themselves in the domestic appliance and automotive
industries but to the best of our knowledge have not heretofore been recognised to
be of value in the very different context of forming part of the structural strength
of a panelled garage door. Not only has it now been established to our satisfaction
that such connections very adequately fulfil that function in a door as described;
a direct consequenoe of the use of such connections is that they lead to a major saving
of resources in terms of welding requirements or rivets.
[0010] Each connection is formed by stretching the two abutting metal components in the
region of the intended correction, sufficiently to press the metal out of the plane
of abutment without piercing the metal surface. A protrusion is thus formed which
is then enlarged laterally (that is, parallel to the plane of abutment) with the result
that the two components are thereby securely held together. One form of apparatus
for forming such joints has been described in United Kingdom Patent Specifications
Nos. 2087284, 2123734 and 2189175, all in the name of BTM Corporation. That form of
connection is identified by the trade mark "Tog-L-Loc" of that company. Another form
of connection of this general type is that provided by Pressotechnik GmbH under the
trade mark TOX.
[0011] The connections may be used to secure togetber adjacent door panels, or to secure
one or more panels to the door frame, or preferably for both of these purposes. The
spacing-apart of the connections is selected according to other details of the door
design and weight but typically such connections are made at a pitch in the region
of 5 to 20 cm, preferably within the range from 7 to 10 cm.
[0012] The invention will now be further described, by way of example only, with reference
to the accompanying drawings, which illustrate one preferred embodiment of a garage
door according to the present invention and wherein:-
Fig. 1 is an elevation from the front of the garage door;
Fig. 2 is a horizontal sectional view of the door of Fig. 1;
Fig. 3 is a detailed sectional view to a larger scale of a connection between adjacent
panels of the door of Figs. 1 and 2; and
Fig. 4 is a detailed sectional view of an alternative form of connection between adjacent
panels.
[0013] The garage door shown simply in Figs. 1 and 2 comprises a frame formed from four
double-box-section steel members 10, welded together at their abutting ends 11 to
form a generally rectangular door chassis. Secured within the frame behind a peripheral
flange on the members 10 are three pressed-steel panels 12, each formed with a flange
13 around its sides and ends. The panels 12 are shown plain in the drawings but will
in practice normally have longitudinal ribs or other pressed features giving a mesure
of additional rigidity and if desired decoration to the panel. Adjacent panels are
connected together and also to the chassis members 10 by connections 14 indicated
diagrammatically in Fig. 2. These connections are spaced uniformly around the peripheries
of the panels 12 at an interval of the order of 8 cm.
[0014] Fig. 3 shows, to a much larger scale, one form of the connectors 14, formed in this
case by a "Tog-L-Loc" machine supplied by BTM Corporation. As illustrated in that
figure, two pressed-steel panels, identified by the reference numerals 15 and 16,
have flanges 17 and 18 respectively running continuously along their mutually adjacent
sides. The flanges in the illustrated embodiment have mating ribs 19 running their
full length to assist in locating the panels in accurate alignment and also to form
a weather-proof seal between the panels. By means of a "Tog-L-Loc" machine, the two
flanges 17, 18 are stretched and deformed locally to form a protrusion 20 which extends
laterally at 21 so as to hold the two flanges together without penetrating the metal
of the flanges.
[0015] Fig. 4 illustrates an alternative, somewhat similar connector formed by pressing
using the TOX (trade mark) system available from Pressotechnik GmbH. In that connector,
the metal of two flanges 22 and 23 on panels 24, 25 is again distorted locally with
the result that mating protrusions 26 and 27 on the flanges hold the two panels securely
together.
[0016] While in connecting together two panels, as illustrated in Figs. 3 and 4, only two
layers of metal are stretched to form the connector, if one of the components to be
connected, for example the double-box section frame member 10, is of double thickness
at the point of connection, the connector may be formed in a similar way simply by
stretching the three superimposed layers of metal.
[0017] It will be apparent that the improved door according to the invention, for example
in the embodiment illustrated in the accompanying drawings, may be manufactured on
a large scale with a substantial reduction in energy requirements and/or materials
consumption as compared with prior metal panelled doors assembled by welding and/or
rivetting, while maintaining the important standards of quality and strength which
are desirable in doors of this general type.
1. An improved garage door which comprises a generally rectangular metal frame (10) and
one or more metal panels (12) located within the frame, the panels being secured to
each other and/or to the frame by a multiplicity of connections (14) at intervals
along the abutting lengths of the panel or frame, characterised in that each connection
(14) comprises a localised non-piercing stretching of the two metal components (10,
12) into a laterally-enlarged protrusion (20, 21; 26, 27), which holds the two components
together.
2. A garage door according to claim 1, characterised in that the generally rectangular
frame is constructed from steel sections (10) welded and/or rivetted together at the
corners of the frame.
3. A garage door according to claim 2, characterised in that the frame is constructed
from double-box section frame members (10).
4. A garage door according to any of the preceding claims, characterised in that it comprises
at least two said metal panels (15, 16; 24, 25), each having flanges (17, 18; 22,
23) running continuously along at least a pair of longer sides thereof, abutting flanges
on adjacent panels being secured together by said connections (14).
5. A garage door according to any of the preceding claims, characterised in that said
connections (14) are made at an interval in the region of 5 to 20 cm.