IMPROVEMENTS IN DOUBLE OR FOLDING DOORS, FRENCH AND SIMILAR CASEMENTS, AND IN APPARATUS FOR SECURING THEM AGAINST HIGH WINDS, BURGLARS, AND OTHER CONTINGENCIES
Year: 1875

page_text: LETTERS PATENT to Otto Eugen Lohnstein, of the Firm Gustave
Spiess and Company, of Mincing Lane, in the City of London, for
the Invention of "IMPROVEMENTS IN DOUBLE OR FOLDING DOORS, FRENCH
AND SIMILAR CASEMENTS, AND IN APPARATUS FOR SECURING THEM AGAINST
HIGH WINDS, BURGLARS, AND OTHER CONTINGENCIES."-A communication
from abroad by Clarence Edward Collings, of Hong Kong, one of
the British Crown Colonies.
Sealed the 12th April 1876, and dated the 26th October 1875.
PROVISIONAL SPECIFICATION left by the said Otto Engen Lohnstein
at the Office of the Commissioners of Patents, with his Petition,
on the 26th October 1875.
I, OTTO EUGEN LOHNSTEIN, of the Firm of Gustave Spiess and
5 Company, of Mincing Lane, in the City of London, do hereby declare
the nature of the said Invention for "IMPROVEMENTS IN DOUBLE OR FOLDING
DOORS, FRENCH AND SIMILAR CASEMENTS, AND IN APPARATUS FOR SECURING THEM
AGAINST HIGH WINDS, BURGLARS, AND OTHER CONTINGENCIES," (communicated

page_text: to me from abroad by Clarence Edward Collings, of Hong Kong, one of
the British Crown Colonies, to be as follows:-
The object of this Invention is to arrange and rigidly connect the
inner and the outer doors or casements of passages and other openings,
whereby the action of high winds and the influx of water during high
tides can be resisted, also burglarious attempts frustrated.
According to this Invention half doors, French window casements,
and Venetian and other shutters are hung upon side stiles or uprights,
one set upon the inside and one set upon the outside to open in contrary
directions, and with the meeting edges overlapped, so that when shut to
they close up the crevices. One of the outer half doors or windows has,
say, a couple of screw pius projecting inwardly from the edge rail, the
heads of which screw pins are recessed into the rail, and firmly held by
nuts on the other or inner side. The screw pins pass through apertures,
say, in one of the inner sashes or half doors, and thumb nuts can then
be passed over them to fasten the two sets of doors or windows firmly.
The inner side of tho two inner half doors has cach one or more bars of
curved form, and their bulged or centre portions are caused to press
against the inner faces of the outer doors, the pressure of one to the
other being effected by the screws and nuts before referred to.
The bars, plain or recessed, may be loose to be slipped in place when
desired by the ends being dropped into socket pieces, or the bars may
bo a fixture upon the half doors.
In the case of the two inner half doors having glass in them it is
preferred to have the bars loose.
The outer half doors may have Venetian slats fitted in them, and in
that case the slats will be operated for opening and closing purposes by
vertical central ribs, which ribs project and are received by a hollow of
the bar when the slats are closed.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Otto Eugen Lohnstein in the Great Scal Patent
Office on the 26th April 1876.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, OTTO
EUGEN LOHNSTEIN, of the Firm Gustave Spiess and Company, of
Mincing Lane, in the City of London, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-sixth day of October, in the
year of our Lord One thousand eight hundred and seventy-five,
in the thirty-ninth year of Her reign, did, for Herself, Her heirs
and successors, give and grant unto me, the said Otto Eugen
Lohnstein, Her special license, that I, the said Otto Eugen Lohnstein,
my executors, administrators, and assigns, or such others as I, the said
Otto Eugen Lohnstein, my executors, administrators, and assigns,
should at any time agree with, and no others, from time to time and
at all times thereafter during the term therein expressed, should and
lawfully might make, use, exercise, and vend, within the United
Kingdom of Great Britain and Ireland, the Channel Islands, and Isle
of Man, an Invention for "IMPROVEMENTS IN DOUBLE OR FOLDING Doors,
FRENCH AND SIMILAR CASEMENTS, AND IN APPARATUS FOR SECURING THEM AGAINST
HIGH WINDS, BURGLARS, AND OTHER CONTINGENCIES," (communicated to me
from abroad by Clarence Edward Collings, of Hong Kong, one of the
British Crown Colonies,) upon the condition (amongst others) that I,
the said Otto Eugen Lohnstein, my executors or administrators, by an
instrument in writing under my, or their, or one of their hands and
seals, should particularly describe and ascertain the nature of the said
Invention, and in what manner the same was to be performed, and cause
the same to be filed in the Great Seal Patent Office within six calendar
months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said Otto Eugen Lohnstein, do hereby
declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement thereof, that is to say :—
The object of this Invention is to arrange and rigidly connect the
inner and the outer doors or casements of passages and other openings.

page_text: whereby the action of high winds and the influx of water during high
tides can be resisted, also burglarious attempts frustrated.
86
According to this Invention half doors, French window casements,
and Venetian and other shutters are hung upon side stiles or uprights,
one "sett" upon the inside and one sett" upon the outside to open
in contrary directions, and with the meeting edges overlapped, that
when shut to they close up the crevices. One of the outer half doors or
windows has, say, a couple of screw pins projecting inwardly from the
edge rail, the heads of which screw pins are recessed into the rail, and
firmly held by nuts on the other or inner side. The screw pins pass
through apertures, say, in one of the inner sashes or half doors, and
thumb nuts can then be passed over them to fasten the two sets of
doors or windows firmly. The inner side of the two inner half doors
has each one or more bars of curved form, and their bulged or centre
portions are caused to press against the inner faces of the outer doors,
the pressure of one to the other being effected by the screws and nuts
before referred to.
The bars, plain or recessed, may be loose to be slipped in place when
desired by the ends being dropped into socket pieces; or the bars may
be a fixture upon the half doors.
In the case of the two inner half doors haying glass in them it is
preferred to have the bars loose.
The outer half doors may have Venetian slats fitted in them, and in
that case the slats will be operated for opening and closing purposes by
vertical central ribs, which ribs project and aro received by a hollow of
the bar when the slats are closed.
The Invention will be clearly understood by the following detailed
description and by the annexed Drawings as applied to a coupled outer
Venetian slat door and an inner glass sash door, each being on the
French casement system.
Figure 1 is a perspective view of a double door looking from the
inside of a room with one of the half doors open; Figure 2 is a vertical
section; and Figure 3, a transverse section.
A, A, are the top and bottom lintels; and B, B, the side stiles, upon or
to which the Ver.ctian slat half doors D, D, are hung by hinges, so as

page_text: to open from the centre. E, E, are screw pins, whose heads à, à, are
sunk into the exterior surface of one of the half doors, i.c., the one with
the "rabbett" or bead on to overlap the meeting edge of the other half
door; b, b, are nuts on the screw pins and on the inner side of the half
door to rigidly fix the pins in position; F, F, are tho Venetian slats
swivelled in the frames, and capable of being opened or closed by a
movement of the central vertical ribs G, G, when desired. These
central vertical ribs project and form bearings for the front edges of
horizontal bars H, H, to impinge against when the thumb nuts I, I, are
fitted over the ends of the screw pins E, E, as in the sectional plan view,
the thumb nuts taking against the inner face of one of the glass half
doors K, K, an operation effecting, when the two sets of doors are closed,
the drawing to and compressing the two rigidly together. The glass
half doors K, K, are hung on the inner edges of the side stiles B, B,
so that they on being opened move to the inside of a room, or in the
reverse direction to the Venetian slat half doors which open outwardly.
The horizontal bars, whether with a plain rounded face, as at c, or
with a recessed face as at d may be fixtures upon the glass half doors;
or they may be detachable, in which case I either screw them firmly on,
or I drop them into sockets e, e, fitted on the inner side faces of the
glass half doors, as particularly shown in Figure 1.
The double half doors as described can be fitted to every construction
or arrangement of building, and they, or either of them, can be wholly
or partially opened to permit of light and air entering the apartment, or
be wholly closed and firmly compressed together by means of the screw
pins and transverse bars to resist the force of high winds or the influx
of water.
The structure is also rendered proof against burglars by the application
of this Invention.
Having thus described the nature of the Invention, and the manner
in which it can be carried into effect, I claim,-
Firstly. Fitting doorways, windows, and other openings or passages
with double half doors to open in contrary directions, which double half
doors can, when closed, be rigidly connected, as and for the purposes set
forth.

page_text: the inside the doors can be drawn towards each other and be rigidly
fixed, as described.
Thirdly. Fitting transverse bars on the inner half doors to bear against
vertical bars or ribs on the outer half doors, as and for the purposes set
forth and as shown in the annexed Drawings.
In witness whereof, I, the said Otto Eugen Lohnstein, have here-
unto set my hand and seal, this Twenty-fifth day of April,
One thousand eight hundred and seventy-six.