Improvements in the Means of Unfastening and Fastening Doors, and in Locks, Bolts, and Latches for that and other similar Purposes.
Year: 1887

page_text: Date of Application, 15th Oct., 1887
Complete Specification Left, 16th July, 1888
Complete Specification Accepted, 24th Aug., 1888
Improvements in the Means of Unfastening and Fastening Doors,
and in Locks, Bolts, and Latches for that and other similar
Purposes.
We, Sir GEORGE HAYTER CHUBB, Knight, of 128 Queen Victoria Street, in the
City of London, Lock and Safe Engineer and Manufacturer, and GEORGE GASKELL
EXTON, of Binfield Road, Clapham, in the County of Surrey, Engineer do hereby
declare the nature of this invention to be as follows:-
Our invention relates more especially to improved means of unfastening and fastening
doors in cases where it is required to secure an extremely easy or automatic means of
opening the door from one side while it cannot be opened from the other, except by
the use of a key or other special means, as for example in the case of the exit doors of
theatres or other public buildings which, as is well understood, it is desirable to keep
secure against entrance from the outside, but which it is of the utmost importance
should be easily opened from the inside in the event of a panic, or for the free
liberation of the persons in the building for any cause whatever. But our invention
also relates to certain improvements in locks and latches which are not only applicable
to the unfastening and fastening of doors under the conditions above mentioned, bu
to other doors and other purposes.
Our improvements in the means of unfastening and fastening exit or panic doors
consist of the following arrangements: We fit to the lock style of the door a
latch adapted to be operated by a push exerted in the direction in which the door
opens. The usual push and pull spindle and knobs are not employed, but, instead
thereof, we employ a more or less projecting surface which may consist of a plate, disc,
or other similar device of any suitable or convenient area, applied and adapted in such
a manner that when such projecting surface is subjected to pressure exerted from the
inside of the door against the counter action of spring or other resistance, the latch is
withdrawn and the continued pressure causes the door itself to fly open. The before-
mentioned projecting surface may, in some cases, be connected directly to the door
post or frame, but so as to open with the door, but it is essential that such yielding
surface shall be so combined with the latch bolt that whenever pressure is exerted
upon such yielding surface by a person, or a crowd of persons, pressing against it, the
latch is thereby withdrawn free of the striking plate and the door is then consequently
free to be pushed open.
In order to prevent an exit or panic door arranged as above described from being
opened from the outside without a special means, we arrange the latch lock in such

page_text: manner that it cannot be opened from the outside except by means of a key introduced
through an external keyhole which is the only visible means of opening from the
outside.
It will be understood that by these arrangements the door can never be locked so
that it cannot be opened from the inside by pressure applied to the beforementioned
internal yielding surface, and that, whenever the door is closed and latched, it cannot
be opened from the outside without the proper key.
When the above arrangements are applied to folding doors, and it is desired that
both leaves of the door shall be free to open when the yielding surface in one is
pressed, and the latch bolt therein withdrawn from the other, we employ a special
arrangement of bolts or latches instead of the ordinary sliding bolts placed at top and
bottom of that leaf of the door which is usually kept closed and bolted. The said
special arrangement consists of a pair of bolts or latches mounted in a suitable case,
and adapted to move at right angles to and in concert with each other. A pair of
these bolts or latches so mounted is secured to the upper corner of the fixed leaf of the
door in the position usually occupied by the upper sliding bolt, and another pair of
such bolts or latches, similarly mounted, is secured to the lower corner of the same
leaf in the position usually occupied by the lower sliding bolt.
These pairs of bolts or latches are each so arranged that one bolt moves horizontally,
and the other vertically; the one being connected to the other by a bell crank lever
or otherwise in such manner that when the horizontal bolt or latch is pressed out by a
spring beyond the vertical edge of the leaf of the door, the vertical bolt or latch is
drawn in flush with or clear of the horizontal, top or bottom edge of such leaf. On
the other hand, if and when the horizontal bolt or latch is pressed inwards more or
less flush with the vertical edge of the door leaf, the corresponding vertical bolt or
latch will be pushed outwards and will, if that door leaf is shut, enter a hole in the
lintel, or in the floor, as the case may be, and that leaf of the door will thereby be
held as securely as by the ordinary hand sliding bolts. It will now be understood
that when both leaves of the door are closed, the edge of the lock style of the opening
leaf of the door will press the aforesaid horizontal bolts or latches inwards and thereby
the vertical bolts or latches upwards and downwards into their holes in the lintel and
floor respectively, so as to hold securely the door leaf to which they are attached.
But whenever the opening leaf of the door is opened, whether from the inside or out-
side, the horizontal bolts or latches are released; they are pushed outwards by their
springs, and draw down and up their respective vertical bolts or latches, thereby
liberating the other leaf of the door so that it is also free to open. Or in some cases
one or both of the vertical bolts or latches may be adapted as slam latches and be so
arranged as to project when in their normal position; the horizontal bolts or latches
serving to prevent such vertical latches from being forced out of their striking plates
by pressure exerted on the door leaf to which they are fitted until after the other door
leaf has been opened.
These last described arrangements are also applicable to ordinary folding doors not
fitted with the automatic opening arrangements above described, and it is obvious that
the arrangement of latch lock operated by pushing from one side, and by a key only
from the other, is applicable to other cases besides exit or panic doors.
Springs, weights, or door checks, of any suitable construction or design, may be
employed, in combination with the above described arrangements, for the purpose of
closing the doors, if and when required.

page_text: COMPLETE SPECIFICATION.
Improvements in the Means of Unfastening and Fastening Doors,
and in Locks, Bolts, and Latches for that and other similar
Purposes.
We, GEORGE HAYTER CHUBB, Knight of 128 Queen Victoria Street, in the City of
London, Lock & Safe Engineer and Manufacturer, and GEORGE GASKELL EXTON, of
Binfield Road, Clapham, in the County of Surrey, Engineer, do hereby declare the
nature of this invention and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement, reference
being had to the accompanying three sheets of Drawings and to the letters and Figures
marked thereon, that is to say :-
Our invention relates more especially to improved means of unfastening and
fastening doors in cases where it is required to secure an extremely easy or automatic
means of opening the door from one side, while it cannot be opened from the other
except by the use of a key or other special means, as for example, in the case of the
exit doors of theatres, or other public buildings, which, as is well understood, it is
desirable to keep secure against entrance from the outside, but which it is of the
utmost importance should be easily opened from the inside in the event of a panic,
or for the free liberation of the persons in the building for any cause whatever. But
our invention also relates to certain improvements in locks and latches which are not
only applicable to the unfastening and fastening of doors under the conditions above-
mentioned, but to other doors and other purposes.
Our improvements in the means of unfastening and fastening exit or panic doors
consist of the following arrangements.
We fit to the lock style of the door a latch adapted to be operated by a push,
exerted in the direction in which the door opens. The usual push and pull spindle
and knobs or handles are not employed, but instead thereof we employ a more or less
projecting surface which may consist of a plate, disc, or other similar device, of any
suitable or convenient area, applied and adapted in such a manner that, when
such projecting surface is subjected to pressure exerted from the inside of the
door against the counter action of spring, or other resistance, the latch_is
withdrawn and the continued pressure causes the door itself to fly open. The
beforementioned projecting surface may, in some cases, be connected directly to
the door post or frame, but so as to open with the door; it is, however, essential that
such yielding surface shall be so combined with the latch bolt that, whenever pressure
is exerted upon such yielding surface by a person, or a crowd of persons pressing
against it, the latch is thereby withdrawn free of the striking plate and the door is
then consequently free to be pushed open.
In the Drawings hereto annexed Figure 1 is the elevation of part of a door with
one arrangement of our improved means of unfastening and fastening applied thereto,
and Figure 2 a sectional plan of same taken on line X X of Figure 1.

page_text: A is the lock style of the door, B a mortice latch lock of the push and pull type
adapted thereto, the segmental latch bolt C being operated by the push and pull
lever D in a manner now well understood. Or, instead of the lock shown in the
Drawing, we may employ locks or fastenings of other construction as, for example,
of the kind registered by Windle and Blyth on 9 August 1850, or as described in
Specifications of Patents granted to Cotterill in 1846, No. 11,152, to Brodie in 1860
No. 1,021, to Imray in 1871 No. 1160, or to Chubb & Exton in 1885 No. 11,901.
In the Drawing, E is a metallic or other suitable plate forming the projecting surface
above mentioned; its edges may be turned down and flanged outwards, as shown in
the section, Figure 2. F is a frame screwed, or otherwise secured, to the base plate G
which is in its turn secured to the middle rail A' or other suitable part of the door.
The plate E, being passed into the frame F from the back before the latter is put in
place, is prevented from coming out beyond the position shown in Figure 2 by means
of the flanges E¹ of the plate. H are stiffening pieces fixed at the ends and, if
necessary, along the sides of the plate E to assist in preventing the said plate from
altering its shape when pressed against. I is a lever turning on a fulcrum 1' secured
to the base plate G. The outer end of the lever I is pressed away from the door by a
spring 12 and presses outwards the corresponding end of the plate E until its flange E¹
bears against the frame F as shown. Jis a similar lever turning on a fulcrum J
secured to the base plate G. The outer end of the lever J is pressed away from the
door by a spring J and, like the lever I, presses outwards the corresponding end of
the plate E until its flange E¹ bears against the frame F as shown. The inner end
of the lever J overlaps the inner end of the lever I as shown. Interposed between the
outer end of the lever J and the push lever D of the latch bolt C is the actuating
pin K.
It will now be understood that if the plate E be pressed at any part of its surface
in the direction of the arrow, the outer end of either, or both, the levers I and J will
be pressed towards the door against the resistance of the springs 13 and J2. If the
end of the plate E, nearest the latch, be pressed, the outer end of the lever J will be
pressed towards the door, and thereby the pin K will be pressed forward, turning the
latch bolt lever D, for example, and withdrawing the segmental latch bolt C from
the striking plate, thus unfastening the door which is then free to open outwards. If
the end of the plate E, furthest from the latch, be pressed, the outer end of the
lever I will be pressed towards the door, and the inner end of that lever will press
the inner end of the lever J away from the door, whereby its outer end is caused
to press the pin K forwards and the latch bolt C is withdrawn from the striking plate
as before. Thus in order to unfasten the door, it is not necessary to find, and to
turn, or push, or pull, a handle of any kind whatever, but simply to push against any
part of the projecting surface E with any part of the body, or with a stick, an
umbrella, or almost any other object. The spring L is for the purpose of keeping
that end of the plate E pressed away from the door and therefore and thereby to
hold it steadily when the other end of the plate is pressed towards the door. The
guard plate or flange M is provided for the purpose of preventing the introduction
of an instrument between the lock style A and the door post for the purpose of
pressing the bolt C inwards and thereby unfastening the door from the outside without
the key. In some cases the base plate G may be dispensed with, the frame F and
the levers I and J being mounted directly on the middle rail A¹ or other suitable
part of the door.
In order to prevent an exit or panic door, arranged as above described, from being
opened from the outside without special means, we arrange the latch lock in such
manner that it cannot be opened from the outside except by means of a key
introduced through an external keyhole which is the only visible means of opening
from the outside, as in the case of an ordinary street door latch which is opened
from the inside by a handle and from the outside by a latch key.
We have
deemed it unnecessary to describe in detail, or to illustrate by Drawings, any
particular arrangements by which this object can be carried out, as such arrangements
will be obvious to any person skilled in the art of lock making.

page_text: In the arrangements above described, and illustrated in Figures 1 and 2 of the
Drawings, the door is intended to open outwards only; but in some cases it is
desirable or necessary that the door should be capable of being opened either inwards
or outwards. To enable this to be done, we hang the door with folding or other
hinges so that it can be opened both inwards or outwards, and apply thereto automatic
unfastening devices, similar to those above described in conjunction with the latch
lock and striking plate illustrated in Figures 3, 4, 5, and 6 in which Figure 3 is an
internal view of the lock with the back plate removed, Figure 4 a section on line YY
of Figure 3, Figure 5 a sectional plan on line Z Z of Figures 3 and 6, and Figure 6
a front elevation of the striking plate.
C is a sliding latch bolt the outer end of which is rounded as shown in Figure 5, so
that when the door is pushed in either direction, the said latch bolt is pressed inwards
by one or other of the inclined planes N N¹ of the striking plate. Similarly, as the
door is closed, the latch-bolt C is pressed inwards by one or other of the inclined
planes OO of the striking plate until it reaches the part where the inclined planes N N¹
occur, when the spring P presses the latch-bolt Coutwards into the space between
the inclined planes N N¹ so as to hold the door in the closed position. Qis an arm
pin-jointed at one end to the inner end of the latch-bolt C, the other end being held
normally by the spring R in the position shown in full lines in Figure 5. S is the
sliding bolt of a lock the levers of which are seen at T in Figure 3 and the key hole
at U in the same Figure. One end of the bolt S is recessed or rebated as shown
clearly at S¹ in Figures 4 and 5, in such manner that when the arm Q is moved
against the action of the spring R into the position shown in dotted lines in Figure 5,
its end comes opposite the said rebate S. K is a pin pressed against the arm Q by
the plate E and lever J of the automatic unfastening apparatus above described in
reference to Figures 1 and 2.
It will now be understood that with the parts in the positions shown in full lines
in Figures 3, 4 and 5, the latch-bolt C cannot be moved inwards because the
rear end of the arm Q comes against the part S2 of the bolt S, and therefore that
whether the door be pushed inwards or outwards the latch-holt C cannot yield and the
door is securely fastened. But if the automatic unfastening apparatus shown in
Figures 1 and 2, which is applied to the inside of the door, be pushed towards the
door, the pin K will press the arm Q into the position shown in dotted lines in
Figures 4 and 5, so that the end of the said arm comes opposite the rebate S' in the
bolt S and the latch bolt C is then free to be moved inwards by the inclined plane N
of the striking plate when the door is pushed in the direction of the arrow in
Figure 5, and the door is thereby made free to open outwards. On the other
hand, the door cannot be opened from the outside when the parts are in the
positions shown in full lines in Figures 3, 4 and 5, because there are no means of
moving the arm Q from the outside into the position shown in dotted lines in
Figures 4 and 5. But when it is desired to open the door from the outside, the key
is inserted at the key hole U, which is on the outer side of the lock, and the bolt S
is moved downwards thereby until its upper end comes below the arm Q when the
latter is free to slide over it, and consequently the latch-bolt C is also free to be pressed
inwards by either of the inclined planes N or N₁ of the striking plate, so that the door
can then be opened either inwards or outwards by simply pushing or pulling it in the
required direction. When the door is again closed, the bolt S can be again shot up
with the key into. the position shown in Figures 3 and 4, and the door is thereby
again secured against entry from the outside, but is free to be opened from the inside
by means of the automatic arrangements before described. If required, the key-
actuated locking mechanism may be two-sided and thus allow of the key being used
from the inside of the door, as well as from the outside. Or the said mechanism may
in some cases be dispensed with altogether.
By the arrangements above described, the door can never be locked so that it
cannot be opened from the inside by pressure applied to the beforementioned internal
yielding surface, and whenever the door is closed and latched it cannot be opened from
the outside without the proper key.

page_text: Figure 8 illustrates a pair of folding doors with the automatic opening arrange-
ment illustrated in Figures 1 and 2, the devices hereinafter described with
reference to Figure 7 for securing the first leaf of the door applied thereto.
When the above arrangements are applied to folding doors (as in Figure 8 for
example) and it is desired that both leaves G H of the door shall be free to open
when the yielding surface on one, G for example, is pressed, and the latch-bolt therein
withdrawn from the other leaf H, we employ a special arrangement of bolts or latches
instead of the ordinary sliding bolts placed at top and bottom of that leaf H of the
door which is usually first closed and bolted. The said special arrangement is shown
in Figure 7 and consists of a pair of bolts or latches A A' mounted in a suitable
case B and adapted to move at right angles to and in concert with each other by
means of a bell crank lever C connecting the two bolts together. A pair of these
bolts or latches so mounted is secured to the upper corner of the first closing leaf of
the door in the position usually occupied by the upper sliding bolt (as for example
at E in Figure 8) and another pair of such bolts or latches, similarly mounted, is secured
to the lower corner of the same leaf in the position usually occupied by the lower sliding
bolt (as for example at F in Figure 8). These pairs of bolts or latches are each so
arranged that one bolt A (Figure 7) moves horizontally and the other A¹ vertically,
the one being connected to the other by the bell crank lever C, or otherwise, in such
manner that when the horizontal bolt or latch A is pressed out by the spring D
beyond the vertical edge of the leaf of the door H, (Figure 8) the vertical bolt
or latch A¹ is drawn in flush with or clear of the horizontal top or bottom edge,
as the case may be, of such leaf. On the other hand, if and when the horizontal
bolt or latch A is pressed inwards more or less flush with the vertical edge of the
said door leaf, the corresponding vertical bolt or latch A' will be pushed outwards
and will, if that door leaf is shut, enter a hole in the lintel or in the floor as the
case may be, and that leaf of the door will thereby be held as securely as by the
ordinary hand sliding bolts. It will now be understood that when both leaves G
and H (Figure 8) of the door are closed the edge of the lock style I of the first
opening leaf G of the door, or a plate thereon will press against the bevilled edges
of the aforesaid horizontal bolts or latches A, and will press such bolts or latches
inwards, and consequently the vertical bolts or latches A¹ upwards and downwards
into their holes in the lintel and floor respectively, so as to hold securely the door
leaf H to which they are attached. But whenever the opening leaf G of the door is
opened, whether from the inside or outside, the horizontal bolts or latches A are
released; they are pushed outwards by the springs D, and draws downwards and
upwards their respective vertical bolts or latches A¹, thereby liberating the other leaf H
of the door so that it is also free to open. When folding doors are adapted to open
in both directions (as hereinbefore described in connection with a single door and
with reference to Figures 4, 5, and 6 of the Drawings) in order to assist in temporarily
retaining the leaf of the door which is first closed in its normal closed position while
the second door is being closed, we sometimes employ a spring or slam bolt thereon,
the nose of which bolt is adapted to take into a recess in the sill or lintel, but so as
to be forced out of its recess when pressure is exerted on the door.
Springs, weights or door checks of any usual and suitable construction or design
may be employed in combination with the above described arrangements for the
purpose of closing the doors automatically or of preventing them from slamming if,
and when required.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, we desire to have it
understood that we are aware that it has been proposed to apply to exit or panic doors
various kinds of handles in connection with push and pull latch locks for the purpose
of facilitating the unfastening and opening of such doors, that a folding or yielding
leaf or lever connected with and actuating quick pitched screw bolts have been applied
for the same purpose, and that latches for securing the first half or leaf of a folding
door have been used in which the vertical bolts take automatically into holes or

page_text: recesses in the lintel and floor when the first door is closed and are prevented from
leaving such holes or recesses by the edge of the second door when the same is
closed; but we make no claim to such arrangements, and we declare that what we do
claim is :-
First The improved apparatus for unfastening and fastening doors which consists
of a plate, disc or other similar device forming a yielding surface so placed and
arranged on the door as to be readily acted upon by a person or other body pressing
or being pressed against the same without the necessity of the person or persons
desirous of effecting egress having to find or operate a handle of any kind, and of
mechanism for actuating the latch bolt, all arranged, combined and operating substan-
tially as hereinbefore described, and illustrated in Figures 1 and 2 of the Drawings
hereto annexed.
Second-The improved apparatus for unfastening and fastening doors which
consists of a plate, disc or other similar device forming a yielding surface so placed
and arranged on the door as to be readily acted upon by a person or other body
pressing or being pressed against the same without the necessity of the person or
persons desirous of effecting egress having to find or operate a handle of any kind,
and of mechanism for liberating a latch bolt so that it may be actuated by inclined
planes on the striking plate in the act of opening the door, all arranged, combined and
operating substantially as hereinbefore described, and illustrated in Figures 3, 4, 5
and 6 of the Drawings hereto annexed.
Third The general arrangement and construction of apparatus whereby doors can
be so fastened that while they cannot be opened from one side without a special
key, they can always be opened from the other side without a handle or special key,
substantially as hereinbefore described, and illustrated in the Drawings hereto
annexed.
Fourth-The latches for securing the first door of a pair of folding doors, con-
structed, applied and operated as hereinbefore described, and illustrated in Figure 7
of the Drawings hereto annexed.