Improvements in or in connection with Collapsible Doors.
Year: 1894

page_text: Date of Application, 17th Jan., 1894
Complete Specification Left, 14th Sept. 1894-Accepted, 20th Oct., 1894
PROVISIONAL SPECIFICATION.
Improvements in or in connection with Collapsible Doors.
I, HENRY BIRKBECK of the Firm of Tongue & Birkbeck, Chartered Patent
Agents, of 34 Southampton Buildings, Chancery Lane, London, Fellow of the
Chartered Institute of Patent Agents do hereby declare the nature of this
invention (a communication from W. Bonfils of Copenhagen, Denmark, Saddler
and Upholsterer) to be as follows :-
In dwellings in which curtains or tapestry hangings or the like are employed for
closing the door opening between two rooms, it is inconvenient that the communi-
cation between the two rooms is always open. The consequence of this is not only
that both rooms will necessarily be heated although perhaps only one room is being
used but it may also often happen that it is desired to converse in one room
without such conversation being liable to be overheard in the other room.
For this and other reasons it would be a great advantage to have independently
of the curtains or hangings a means of shutting off one room from the other such
that the said shutting off mechanism shall not be in the way when it is not required
for use.
This is the object of the collapsible door forming the subject matter of
the present invention.
The door-opening has a framing and has a collapsible door capable of being
drawn out so as to fill up the whole of the door-opening or collapsed out of
the way
The framing of the collapsible door is composed of vertical wooden or other bars
and each bar consists of two parts.
The bar which is fixed to the door frame is cut out to a special or suitable shape.
The other bars are only partly cut to the shape of the first-named bar in order to
afford room for the operating mechanism.
The wooden bars are connected by metal or other suitable strips which cross one
another and are connected together by bolts or other suitable fastenings and are
also pivotted to the aforesaid wooden bars.
At that part of the metal strips which is situated nearest to the rearmost bar oue
leg thereof is prolonged and is rivetted to guide bars each of which slides in holes
in two angle pieces attached to the wooden bar.
In order that both the uppermost and the lowermost folding or collapsible parts
shall move simultaneously same are connected with a connecting rod (carrying the
guide bars) which is connected by bolts or other suitable fastenings with prolonged
pieces of the aforesaid folding parts.
A covering which consists of paper-board or canvas with cloth felt or the like or
of other suitable material is glued or nailed to the wooden bar and is pressed into
the form of sharp folds in such a manner that the covering will assume a zig-zag
form when the door is pushed together or collapses.
Bars or fillets are fixed at the top and bottom of the door opening for the purpose
of guiding the door.
In the case of double doors two half collapsing doors are employed and a covering
fillet is fixed on the front edge in order to provide a tight joint for the door at the
place where the two half doors meet.
Dated this 17th day of January 1894.

page_text: COMPLETE SPECIFICATION.
Improvements in or in connection with Collapsible Doors.
I, HENRY BIRKBECK of the Firm of Tongue & Birkbeck Chartered Patent
Agents of 34, Southampton Buildings, Chancery Lane, London, Fellow of the
Chartered Institute of Patent Agents, do hereby declare the nature of this
invention (a communication from W. Bonfils of Copenhagen, Denmark, Saddler
.and Upholsterer) and in what manner the same is to be performed to be
particularly described and ascertained in and by the following statement :—
In dwellings in which curtains or tapestry hangings or the like are employed for
closing the door opening between two rooms it is often inconvenient or undesirable
that the communication between the two rooms should be always open. The
consequence of this is not only that both rooms will be heated although perhaps
only one room is being used but it may also often happen that it is desired to
converse in one room without such conversation being liable to be overheard in the
other room.
For this and other reasons it would be a great advantage to have independently
of the curtains or hangings a means of shutting off one room from the other such
that the said shutting off mechanism shall not be in the way when it is not required
for use. This is the object of the present invention which I will now proceed to
describe with reference to the accompanying drawings:-
Fig. 1 illustrates a single door-opening with frame showing a collapsible door
according to my present invention so as to fill up the whole of the door-opening.
A is the fixed frame in which operates the door according to this invention.
The framing of the collapsible door itself consists of the vertical posts
(advantageously wooden uprights) a' a' a' a' each such post or bar consisting of
two parts with vertical slots transversely through each or it may be a single post
similarly slotted in the manner shown in elevation (edge view) in Figs. 2 and 3.
The bar at which is fixed to the door frame A is specially cut out or suitably
formed to a shape such as shown in Fig. 2. The other bars a a³ a³ are only partly
cut out i.e. to the shape such as shown in Fig. 3 in order to afford room for the
operating parts as hereinafter explained.
The said bars or uprights are connected by metal or other suitable strips I which
cross one another and are connected together by headed pins k or other suitable
fastenings and are pivotted at to the said uprights a¹ a³ a³ a*.
At that part of the cross strips I (which latter form what is known as "lazy
tongs") which is situated nearest to the bar a one leg thereof or strip M is pro-
longed and such extension on each of the said lazy tongs is respectively pivotted
to a guide pin B each of which respectively slides in a guide hole in the two angle
pieces C attached to the said bar a'.
In order that both the upper and the lower lazy tongs shall only move
simultaneously the aforesaid guide pins B are respectively attached to the rigid
connecting rod D which latter is thus connected with said extension pieces M and
thereby with the two lazy tongs.
Fig. 4 is a horizontal section through the sliding door and shows the covering
(for the aforesaid collapsible framing) which consists of paper board, canvas, cloth,
felt, or the like or of other suitable material or combinations of materials.
This covering F is glued or nailed or otherwise suitably affixed to the aforesaid
uprights a¹ a³ a³ a' and is pressed or formed into the form of sharp folds in such a
manner that the covering will assume a zig-zag form when the door is pushed
together or collapsed-after the manner of "bellows."
Bars or fillets G are fixed at the top and bottom of the door opening for the
purpose of guiding, the door-corresponding recesses H being formed in the ends
of a a a³ (see Fig. 3) to travel on such guide rails G.

page_text: Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. A collapsible door for the purposes described consisting of the combination
with a door frame of a series of upright bars or posts two lazy tongs respectively
pivotted to all of said posts an arm extending from each said lazy tongs
respectively attached to a sliding connecting rod guideways on the fixed part of
the framing in which said connecting rod is held and guided so that equal
movement is thereby imparted to each such lazy tongs and through same to all the
uprights and a covering arranged bellows fashion on said collapsible and extensible
framing substantially as herein before set forth.
2. Collapsible doors constructed and arranged to act substantially in the manner
and for the purposes hereinbefore described and illustrated in the drawings hereunto
annexed.
Dated this 14th day of September 1894,
TONGUE & BIRKBECK,
34, Southampton Buildings, Chancery Lane, London, W.C.,
Agents for the Applicant.