IMPROVEMENTS IN LOCKS AND LATCHES
Year: 1867

page_text: LETTERS PATENT to Thomas Jones, of Birmingham, in the County of
Warwick, Locksmith, for the Invention of "IMPROVEMENTS IN LOCKS AND
LATCHES"
Sealed the 7th January 1868, and dated the 27th July 1867.
PROVISIONAL SPECIFICATION left by the said Thomas Jones at the
Office of the Commissioners of Patents, with his Petition, on the
27th July 1867.
I, THOMAS JONES, of Birmingham, in the County of Warwick, Locksmith,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN LOCKS
AND LATCHES," to be as follows:-
My Invention consistsofthe additionofthemechanismherein-afterexplained
tolocks and latcheshavingspringboltswithbevilledends, whichsaid mechanism
has for its object to prevent the bolt of the lock or latch being forced back by
pressure applied to its end.
My Invention is particularly applicable to locks and latches, the mechanism
of which is of a cylindrical or barrel form, but is also applicable to locks and
latches the mechanism of which is of other kinds.
I will describe my Invention as applied to a spring latch having a barrel
lock. Immediately over the bolt is a lever turning upon a pin in the latch

page_text: case; the said lever is pressed upon by a spring, that end of the spring which
presses on the lever being of a V or convex shape and bearing upon a projection
on the lever immediately over the pin on which it turns. The said projection
is also of a V or convex shape. On the barrel of the lock is a projecting piece,
which on turning the said barrel comes against a projection on the under side
of the lever and raises the long arm of the lever, or that end of the lever
turned towards the bevilled end of the bolt. The lever remains in the raised
position during the further motion of the barrel and the withdrawal of the
bolt. After the opening of the door and the withdrawal of the key the said
lever retains its raised position until the closing of the door, when the forcing
back of the bolt causes a shoulder on its inner end to strike against the tail
of the lever and depress the long arm of the said lever, causing it to engage
at the back of the head of the bolt and to prevent the motion of the bolt
inwards. The bolt cannot now be forced back by the insertion of a tool or
instrument between the door and door frame. The introduction and turning
of the key effects the raising of the lever and the liberation of the bolt in the
manner herein-before described. The lever is retained in one or other
of the positions described by the V-shaped end of the spring pressing upon one
or other side of the centre of the V-shaped projection over the axis of the said
lever.
In order to enable a person inside the room to liberate the latch bolt without
the use of a key a small knob outside the latch case may be connected
through a slot in the latch case with the lever. By means of the said knob
the lever may be raised and the bolt liberated.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Thomas Jones in the Great Seal Patent Office on the 24th
January 1868.
TO ALL TC WHOM THESE PRESENTS SHALL COME, I, THOMAS
JONES, of Birmingham, in the County of Warwick, Locksmith, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-seventh day of July, in the year of our Lord
One thousand eight hundred and sixty-seven, in the thirty-first year of Her
reign, did, for Herself, Her beirs and successors, give and grant unto me,
the said Thomas Jones, Her special licence that I,the said Thomas Jones, my

page_text: executors, administrators, and assigns, or such others as I, the said Thomas
Jones, 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 LOCKS AND LATCHES," upon
the condition (amongst others) that I, the said Thomas Jones, 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 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 Thomas Jones, do hereby declare
the nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof, that is to say:-
My Invention consists of the addition of the mechanism herein-after
explained to locks and latches having spring bolts with bevilled ends, which
said mechanism has for its object to prevent the bolt of the lock or latch being
forced back by pressure applied to its end.
My Invention is particularly applicable to locks and latches, the mechanism
of which is of a cylindrical or barrel form, but is also applicable to locks and
latches, the mechanism of which is of other kinds.
I will describe my Invention as applied to a spring latch having a
barrel lock. Immediately over the bolt is a lever turning upon a pin in the
latch case. The said lever is pressed upon by a spring, that end of the spring
which presses on the lever being of a V or convex shape and bearing upon a
projection on the lever immediately over the pin on which it turns. The said
projection is also of a V or convex shape. On the barrel of the lock is a pro-
jecting piece, which on turning the said barrel comes against a projection on
the under side of the lever and raises the long arm of the lever, or that end
of the lever turned towards the bevilled end of the bolt. The lever remains
in the raised position during the further motion of the barrel and the with-
drawal of the bolt. After the opening of the door and the withdrawal of the
key the said leverretains its raised position until the closing of the door, when
the forcing back of the bolt causes a shoulder on its inner end to strike against
the tail of the lever and depress the long arm of the said lever, causing it to

page_text: engage at the back of the head of the bolt, and to prevent the motion of the
bolt inwards. The bolt cannot now be forced back by the insertion of a tool
or instrument between the door and door frame. The introduction and
turning of the key effects the raising of the lever and the liberation of the
bolt in the manner herein-before described. The lever is retained in one or
other of the positions described by the V-shaped end of the spring pressing
upon one or other side of the centre of the V-shaped projection over the axis
of the said lever.
In order to enable a person inside the room to liberate the latch bolt
without the use of the key a small knob outside the latch case may be con-
nected through a slot in the latch case with the lever. By means of the said
knob the lever may be raised and the bolt liberated.
Having explained the nature of my Invention I will proceed to describe,
with reference to the accompanying Drawing, the manner in which the same
is to be performed.
Figures 1 and 2 represent my Invention applied to a latch having a barrel
or cylindrical lock, Figure 1 representing an elevation (partly in section) of
the latch, the safety mechanism being shown in action, and Figure 2 repre-
senting the said mechanism out of action; Figure 3 represents in elevation
and edge view the said safety mechanism separately. The same letters indicate
the same parts in Figures 1, 2, and 3. a is the latch bolt, and a³ its bevilled
head, the said bolt being pressed outwards by the spring b; cis the barrel of
the lock turning freely in the latch case; the said barrel lock is of the
ordinary kind and constitutes no part of my Invention. Immediately over the
bolt a is a lever d, d', turning on the pin or centre d³ fixed to the latch case
and pressed down by the spring e, the free end of which spring has a V-shaped
projection which bears upon the V-shaped projection d4 on the lever. Upon
the under side of the longer arm d² of the lever is a projecting piece of the
shape represented, and on the barrel c of the lock is a projection c2. When
the lever d, d³, is in the position represented in Figure 1 the end of its
arm d³ is engaged with the depression a³ at the back of the bevilled head of
the bolt, and prevents the bolt being forced back by the insertion of a tool or
instrument between the door and door frame. When it is wished to withdraw
the latch bolt a, a, from the outside of the door the key is introduced into
the lock and the bolts of the lock withdrawn in the usual manner. The
barrel c is then turned by the key, and the projection c² on the said barrel is
made to strike the projection on the lever d, d², and raise the long arm da
of the said lever from the depression a³ in which it was engaged, and thereby

page_text: liberate the bolt as illustrated in Figure 2. By the further motion of the
barrel c its projection c² strikes the pin a¹ on the bolt a and withdraws the
said bolt. The lever d, d³, is retained in one or other of the positions repre-
sented in Figures 1 and 2 by the V-shaped end of the spring e bearing upon
one or the other side of the centre of the V-shaped projection a' onthelever, as
represented. The lever d, d³, remains in the position represented in Figure 2
while the bolt is withdrawn, the door is opened, and the key is withdrawn from
the latch, but on closing the door the forcing back of the bolt causes the end
of the arm d² of the said lever to be re-engaged with the bolt in the following
manner: As the bolt a is forced back by the striking plate a projection a
on the rear end of the bolt strikes against the projecting end of the arm d of
the lever, raising the said arm and depressing the opposite arm d², the end of
the said arm da bearing during the withdrawal of the bolt upon the part aⓇ
of the said bolt, so that when the door is closed and the bolt a forced outwards
by its spring 6 the end of the long arm of the lever engages with the
depression a³, and prevents the motion of the bolt inwards. When the latch
bolt is withdrawn by the key, as first described, the said latch bolt acts upon
and depresses the arm d² of the lever in the manner just described, but in
consequence of the position of the projection c² of the barrel c with respect to
the arm d² of the lever the said arm cannot descend far enough to engage
with the depression a³ of the bolt. Hence the latch bolt is permitted to be
forced back on the closing of the door. Outside the latch case is a small
knob g connected through a curved slot in the latch case with the lever d, d².
By means of this knob g a person inside the room may raise the said lever and
liberate the latch bolt a without the use of the key. The sliding or with-
drawing of the latch bolt inside the room is effected by a knob outside the
latch case, as is usual.
Figures 4 and 5 represent my Invention applied to a latch having a lever
lock, Figure 4 representing the latch in elevation, partly in section, the safety
mechanism being in action, and Figure 5 the same, with the said safety
mechanism out of action; Figure 6 represents a back elevation of the latch,
and Figure 7 represents in elevation and edge view the safety mechanism
separately. The same letters of reference indicate the same parts in Figures 4,
5, 6, and 7. h is the latch bolt, and h² its bevilled head; i is the spring for
forcing it outwards; k,. are the levers of the lock. Under the said levers
is the slide 1, the said slide being guided in its motion by the pins and slots
at m; the said levers and slide are situated within the hollow frame or body/
of the latch bolt. On the slide is the stump n which engages with the

page_text: gatings of the levers.
p, p², is the safety lever, and q the spring of the same;
r is the knob by which the lever p, p, may be raised and the bolt liberated
from inside the room. When the lever p, p, is in the position representedin
Figure 4, the end of the arm p² bears against the back of the head of the
latch bolt at h³, and prevents the forcing back of the said latch bolt, the pro-
jection p³ on the said lever occupying a recess in the slide 1, as represented,
In order to withdraw the latch bolt by the key from the outside of the door
the said key is made to raise the levers k, k, and advance the slide l, so as to
cause its end to strike against the tail of the latch bolt h and withdraw the
said latch bolt. On the first motion of the slide 1, the projection 2 on the
said slide strikes against and raises the arm p² of the lever into the position
represented in Figure 5, and thereby permits of the withdrawal of the latch
bolt. When the arm p² of the lever p, p, is raised the hooked end of the
opposite arm p enters a recess at in the top of the latch bolt, the said lever
being maintained in that position during the withdrawal of the latch bolt by
the key, the opening of the door, and the withdrawal of the key from the
latch. When however the door is closed the forcing back of the latch
bolt h, h², causes the bevilled end of the recess h' to strike against and raise
the arm p of the lever and depress its opposite arm p³, and cause the end of
the said arm p³ to engage with and prevent the forcing back of the latch bolt,
in the manner represented in Figure 4. The latch bolt h is provided with
the ordinary knobs outside the latch case for working it. A pin or bolt t
attached to the outside of the latch case by a chain may be passed through
the latch case to hold the latch bolt out of action when the latch is not
required to be used. In Figures 4 and 5 the hole in the latch case through
which the said pin passes is marked t2, and the hole for the said holding bolt
is marked u in Figures 1 and 2.
My Invention is applicable to the spring bolts of latches, whether combined
with locks or used separately.
Having now described the nature of my Invention, and the manner in
which the same is to be performed, I wish it to be understood that I do not
limit myself to the precise details herein described and illustrated, as the same
may be varied without departing from the nature of my Invention; but I
claim as my Invention the improvements in locks and latches herein-before
described and illustrated in the accompanying Drawing, that is to say,
applying to locks and latches having bevil-ended spring bolts a lever for pre-
venting the said spring bolts from being forced back by pressure applied to
their ends, the said lever and the parts concerned in its action being con-

page_text: tructed and arranged or combined substantially as described and illustrated'
also liberating the said spring bolts from the said lever either by the
unlocking of the said spring bolts or by a knob outside the lock or latch
case, substantially as described and illustrated.
In witness whereof, I, the said Thomas Jones, have hereunto set my hand
and seal, this Twenty-second day of January, in the year of our Lord
One thousand eight hundred and sixty-eight.
Witness,
RICHARD SKERRETT,
Clerk to George Shaw,
Birmingham.
THOMAS JONES.
(L.S.)