IMPROVEMENTS IN LATCHES AND LOCKS
Year: 1883

page_text: PROVISIONAL SPECIFICATION left by the said Frederick James Biggs at
the Office of the Commissioners of Patents on the 2nd October 1883.
FREDERICK JAMES BIGGS of Leadenhall Buildings in the City of London,
"IMPROVEMENTS IN LATCHES AND LOCKS "
Latches in which the bolts are capable of being locked by means of a key (and
commonly called latch locks) have, as hitherto constructed, a great defect namely
that the handle by which the latch is drawn back cannot be turned or moved when
the latch is locked, the result of which is that persons apply great force to the
handle in the hope of turning or moving it and thus the latch mechanism is liable
to be strained and even broken.
Now in order to obviate this defect I construct latches of the kind referred to in
such manner that they are locked. by the latch being blocked or thrown forward
and simultaneously thrown out of gear or connection with the handle, the handle
being thus free to be turned or moved but without acting upon the lock; and
that when the latch is unlocked, the handle is again put into gear or connection
therewith, so as when turned or moved to draw back the latch. I can effect this
in several ways. According to one modification I divide the bolt into two parts to
one of which the latch is connected while the other is capable of being acted upon
by the handle. This latter part carries a stump which when the latch is unlocked
takes into a notch in a tumbler connected with the part which carries the latch
so that when the handle is turned the whole of the parts are moved together;
when on the other hand the latch is locked the tumbler, which has been lifted and
moved forward by the key in the act of locking, is free of the stump so that, when
the handle is turned it only moves the part which carries the stump, the part which
carries the latch not being affected. The latch is locked by a projection on the
tumbler taking in front of a projection on the lock case. According to another
modification a part of the bolt which is capable of being acted upon by the handle
has one or more claws which take into corresponding claws on a part connected
with the latch but capable of being moved a certain amount on its axis. When the
latch is locked the tumbler which is lifted and moved forward by the key in the
act of locking moves the part connected with the latch upon its axis so that the
claws are released from each other.
The handle may be made to act in any ordinary manner but I prefer the
following novel arrangement which is applicable not only to the latch locks above
described but also to other latches. Around the sleeve or socket through which the
ונ0 ...Fo

page_text: spindle of the handle passes I form a toothed wheel and within the latch or lock
case I fit two racks taking into the toothed wheel and facing each other. Each of
these racks has a claw to take on to a projection on the bolt.
Thus when the
handle is turned, no matter in which direction, the one rack is moved forward and
the other backward, that which moves backward drawing back the bolt.
5
Another part of my invention consists of a mode of making the latch reversible,
that is to say, capable of being adapted to either a right hand door or a left hand
door. For this purpose I fit in a circular hole or opening in the end of the latch
or lock case a disc which is free to be rotated therein when not held by a catch.
This disc has a rectangular hole to give passage to the bevelled end of the latch
bolt this bevelled end is not rigidly fixed to the bolt but is free to be rotated
thereon with the disc aforesaid. The disc is formed with two notches or recesses
at diametrically opposite points and in connection with these notches is a catch
which always takes into one or other of them. The catch is by preference a spring
attached to the inside of the end plate. If the bevelled end of the bolt is in 1
position for say a right hand door and it is required to apply the latch or lock to
a left hand door the catch is temporarily freed from the notch of the disc, the
bevelled end and disc are then moved half round on their axis by turning the
bevelled end by hand; the other notch of the disc will then be in position to
receive the catch and thereby hold the bevelled end in the reversed position, that
is to say, for a left hand door.
When my latches or locks are intended to be used as mortise latches or locks I
prefer to make the cases of tubular form because they will then fit into a round
mortise made by an auger; the tedious process of cutting a mortise as is required
for an ordinary rectangular mortise lock or latch is thus dispensed with. But as a s
tubular case sometimes gives too limited a space for the lock mechanism I combine
the advantages of both tubular and rectangular cases by making a portion of the
tubular case viz: the part nearest the outside with upper and lower extensions so
as to afford sufficient height to receive the mechanism. After mortising out by
means of an anger a round hole such as would receive a tubular case it is easy to
widen the outer part of the hole by a chisel so that the upper and lower extensions
above described can fit therein.
In latch bolts which have a spherical ended latch or a latch in the form of a ball
or sphere carried in a cup within the case and which are used in connection with
corresponding striking plates or receivers on the door frame it has hitherto not been
possible to lock the latch by shooting the bolt forward beyond its normal position.
Now I construct spherical ended latch bolts which can be shot or withdrawn as
required by means of a key and the normal position of which is shot. On that
part of the bolt which is within the lock case (this case being. by preference made
tubular) I form a stump to take into recesses and slots in a tumbler. In the normal
or shot position the bolt cannot be withdrawn because the stump is held by a
projection on the tumbler but when the key is inserted in the lock and turned the
tumbler is thereby raised freeing the bolt and the bolt is withdrawn to such an
extent that only the spherical end protrudes beyond the front plate; the door can
then be opened in either direction as with an ordinary spherical ended latch bolt.
The spring of the bolt is preferably a spiral spring fitted within a cylindrical part
of the bolt and bearing against a stop in the case.
I also make latch, locks having the latch in the form of a sphere with the sphere
fitted in the striking plate instead of in the door, the said plate having' behind it a
chamber to contain the spring this chamber being also capable of receiving the
whole of the sphere. The lock itself has a bolt with a concave recess in front to
receive the sphere. In the normal position the bolt does not project beyond the
front plate of the lock but when it is wished to prevent the lock being opened the
bolt is shot forward by means of any suitable lock mechanism so as to drive the
sphere into the chamber behind the striking plate the bolt itself following it a
certain distance into. the said chamber and thus locking the parts together."

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Frederick James Biggs in the Patent Office on the 2nd April
1884.
FREDERICK JAMES BIGGS of Leadenhall Buildings in the City of London
"IMPROVEMENTS IN LATCHES AND LOCKS
"
Latches in which the bolts are capable of being locked by means of a key (and
commonly called "latch locks") have, as hitherto constructed, a great defect
namely that the handle by which the latch is drawn back cannot be turned or
moved when the latch is locked, the result of which is that persons apply great
force to the handle in the hope of turning or moving it and thus the latch
mechanism is liable to be strained and even broken.
Now in order to obviate this defect I construct latches of the kind referred to in
such manner that they are locked by the latch being blocked or thrown forward
and simultaneously thrown out of gear or connection with the handle the handle
being thus free to be turned or moved but without acting upon the lock and that
when the latch is unlocked the handle is again put into gear or connection
therewith so as when turned or moved to draw back the latch. I can effect this in
several ways. One modification is by the particular arrangement represented in
Figures 1, 2 and 3 of the annexed drawings. Figure 1 is a side view of the lock
with the parts in their normal position the side of the lock case being removed,
Figure 2 is a similar view with the latch locked or blocked and with the handle
turned as in the act of opening the latch. Figure 3 is a section on the line
1 of Figure 1. a is the lock case, b the front plate, c the spindle of
the handle taking into a square hole in a sleeve or socket d which carries 2 horns
or lugs ee; one of these lugs when the handle is turned acts upon inclines ff on
the back portion of the bolt. According to the modification here shown I divide
the bolt into 2 parts g and to one of which h the latch i is connected, while the
other g is capable of being acted upon by the handle as already stated. This part g
carries a stump k which when the latch is unlocked takes into a notch in a tumbler m
connected by means of a pin n with the part h which carries the latch i so that
when the handle is turned the whole of the parts are moved together; the spring o
which surrounds the pin p being compressed against the fixed stop 9; when on the
other hand the laichi is locked the tumbler m which has been lifted and moved
forward by the key (inserted at r) in the act of locking, is free of the stump k so
that when the handle is turned it only moves the part g which carries the stump,
the part which carries the latch not being affected. The latch is locked by a
projections on the tumbler taking in front of a projection t on the lock case.
order to prevent any risk of the stump k and the tumbler blocking each other in
case the latch is unlocked by the key whilst the handle is turned, I bevel the
stump as shown and also the part of the tumbler against which it strikes.
In
Another part of my invention consists of a mode of making the latch reversible
that is to say capable of being adapted to either a right hand door or a left hand
door. For this purpose I fit in a circular hole or opening in the front plate b of
the latch or lock case a disc u which is free to be rotated therein when not held
by a catch. This disc has a rectangular hole to give passage to the bevelled end i
of the latch bolt,-see Figure 4 which is a section on the line 2
2 of
Figure 1; this bevelled end is not rigidly fixed to the bolt h but is free to be
rotated thereon with the disc u aforesaid. The disc is formed with 2 notches or
recesses w w at diametrically opposite points and in connection with these notches
is a catch which always takes into one or other of them. The catch is by

page_text: preference a spring as shown attached to the inside of the front plate b. If the
bevelled end of the bolt is in position for say a right hand door and it is required
to apply the latch or lock to a left hand door the catch vis temporarily freed from
the notch w of the disc, the bevelled end and disc are then moved half round on
their axis by turning the bevelled end by hand; the other notch of the disc will
then be in position to receive the catch and thereby hold the bevelled end in the
reversed position that is to say for a left hand door.
The handle may be made to act in any ordinary manner. but the novel
arrangement which I am about to describe and which is applicable not only to the
latch locks above explained but also to other latches is what I prefer in most enses.
Figures 5 and 6 represent this arrangement with the parts in two positions.
Figure 7 is a section on the line 3-
3. Around the sleeve or socket d
through which the spindle cof the handle passes I form a toothed wheel-x-and
within the latch or lock ouse I fit 2 racks y-y taking into the toothed wheel and
facing each other. Each of these racks has a claw to take on to a projection 1
on the belt g. Thus when the handle is turned, no matter in which direction, the
one ruck is moved forward and the other backward see Figure 6 that which
moves backward drawing back the bolt.
When my latches or locks are intended to be used as mortise latches or locks
I prefer to make the cases of tubular form as shown in the figures because they
will then fit in to a round mortise made by an auger; the tedious process of cutting
a mortise as is required for an ordinary rectangular mortise lock or latch is thus
dispensed with. But as a tubular case sometimes gives too limited a space for the
lock mechanism particularly when there is a lock separate from the latch I combine
the advantages of both tubular and rectangular enses by making a portion of the
tubular case viz: the part nearest the outside with upper and lower extensions se
as to afford sufficient height to receive the mechanism. This improved lock case is
represented in Figures 5, 6 and 7, A and B being the upper and lower extensions
to the tubular ense a-a. After mortising out by means of an auger a round hole
such as would receive a tubular case it is easy to widen the outer part of the hole
by a chisel or gouge so that the upper and lower extensions above described can fit
therein.
In latch bolts which have a spherical ended latch or a latch in the form of a ball
or sphere carried in a cup within the case and which are used in connection with
corresponding striking plates or receivers on the door frame it has hitherto not
been possible to lock the latch by shooting the bolt forward beyond its normal
position.
Now I construct spherical ended latch bolts which can be shot or withdrawn as
required by means of a key and the normal position of which is shot. This part of
my invention is represented in Figures 8 and 9, Figure 8 shewing the parts in
their normal positions while Figure 9 shews them in the positions they occupy
when the bolt is withdrawn. a is the bolt and b its spherical end which is kept
shot by the spring c. On that part of the bolt which is within the lock case (this
case being by preference made tubular) I form a stump d to take into recesses and
slots in a tumbler e. In the normal or shot position Figure 8 the bolt cannot be
withdrawn because the stump d is held by a projection f on the tumbler e but
when the key is inserted in the lock and turned the tumbler is thereby raised
freeing the bolt and the bolt is withdrawn by the key to such an extent that only
the spherical end protrudes beyond the front plate; the stump d being now held
back by the other side of the projection f the door can then be opened in either
direction as with an ordinary spherical ended latch bolt. The spring c of the bolt
is preferably a spiral spring as shewn fitted within a cylindrical part of the bolt and
bearing against a stop g in the case. Figure 10 is a section on the line 4
of Figure 8.
4
I also make latch locks having the latch in the form of a sphere with the sphere
fitted in the striking plate instead of in the door. Figures 11 and 12 represent this
part of my invention, a being the sphero fitted in the striking plate b; this plate

page_text: has behind it a chamber d to contain the spring e this chamber being also capable
of receiving the whole of the sphere a. The lock itself has a bolt f with a concave
recess in front to receive the sphere. In the normal position shown in Figure 11
the bolt does not project beyond the front plate of the lock but when it is
wished to prevent the lock being opened the bolt is shot forward, see Figure 12, by
means of any suitable lock mechanism so as to drive the sphere a into the
chamber d the bolt itself following it a certain distance into the said chamber and
thus locking the parts together.
Having now described the nature of my said invention and in what manner the
same is to be performed I declare that I claim as my improvements in latches and
locks :-
1. Constructing latches of the kind commonly called "latch locks" in such manner
that when the latch is locked it is thrown out of gear or connection with the
handle which is thus free to be moved or turned without-acting upon the latch
substantially as and for the purpose herein before-described.
21. The particular arrangement substantially as herein before described and repre-
sented in Figures 1, 2 and 3 whereby when the latch is locked it is thrown out of
gear or connection with the handle which can then be moved or turned without
acting upon the latch.
3. 2. The mode or method herein before described and represented in Figures 1, 2
and 4 of making latches reversible.
4. The novel arrangement substantially as hereinbefore described and represented
in Figures 5, 6 and 7 by which the handle is made to act upon the bolt of latches
or locks.
5. Constructing mortise latches or looks with tubular cases having extensions or
enlargements at the part nearest the outer and substantially as hereinbefore
described and represented in Figures 5, 6 and 7.
6. 3. Constructing spherical ended latch bolts substantially as hereinbefore described
and represented in Figures 8, 9 and 10 so that the bolt can be shut or withdrawn
by means of a key.
7. 4. Constructing latch locks with the latch in the form of a sphere fitted in the
striking plate and so arranged that when the bolt is shot it drives and follows the
sphere into a chamber behind the striking plate substantially as hereinbefore
described and represented in Figures 11 and 12.
In witness whereof I the said Frederick James Biggs have hereunto set my
hand and seal this twenty ninth day of March One thousand eight hundred and
eighty four.

page_text: LETTERS PATENT to Frederick James Biggs of Leadenhall Buildings in the
City of London for an Invention of "IMPROVEMENTS IN LATCHES AND
FANWA "
PROVISIONAL SPECIFICATION left by the said Frederick James Biggs at
the Office of the Commissioners of Patents on the 2nd October 1883.
FREDERICK JAMES BIGGS of Leadenhall Buildings in the City of London,
"IMPROVEMENTS IN LATCHES AND LOCKS
"
Latches in which the bolts are capable of being locked by means of a key (and
commonly called latch locks) have, as hitherto constructed, a great defect namely
that the handle by which the latch is drawn back cannot be turned or moved when
the latch is locked, the result of which is that persons apply great force to the
handle in the hope of turning or moving it and thus the latch mechanism is liable
to be strained and even broken.
Now in order to obviate this defect I construct latches of the kind referred to in
such manner that they are locked by the latch being blocked or thrown forward
and simultaneously thrown out of gear or connection with the handle, the handle
being thus free to be turned or moved but without acting upon the lock; and
that when the latch is unlocked, the handle is again put into gear or connection
therewith, so as when turned or moved to draw back the latch. I can effect this
in several ways. According to one modification I divide the bolt into two parts to
one of which the latch is connected while the other is capable of being acted upon
by the handle. This latter part carries a stump which when the latch is unlocked
takes into a notch in a tumbler connected with the part which carries the latch
so that when the handle is turned the whole of the parts are moved together;
when on the other hand the latch is locked the tumbler, which has been lifted and
moved forward by the key in the act of locking, is free of the stump so that when
the handle is turned it only moves the part which carries the stump, the part which
carries the latch not being affected. The latch is locked by a projection on the
tumbler taking in front of a projection on the lock case. According to another
modification a part of the bolt which is capable of being acted upon by the handle
has one or more claws which take into corresponding claws on a part connected
with the latch but capable of being moved a certain amount on its axis. When the
latch is locked the tumbler which is lifted and moved forward by the key in the
act of locking moves the part connected with the latch upon its axis so that the
claws are released from each other.
The handle may be made to act in any ordinary manner but I prefer the
following novel arrangement which is applicable not only to the latch locks above
described but also to other latches. Around the sleeve or socket through which the
spindle of the handle passes I form a toothed wheel and within the latch or lock

page_text: case I fit two racks taking into the toothed wheel and facing each other. Each of
these racks has a claw to take on to a projection on the bolt. Thus when the
handle is turned, no matter in which direction, the one rack is moved forward and
the other backward, that which moves backward drawing back the bolt.
Another part of my invention consists of a mode of making the latch reversible,
that is to say, capable of being adapted to either a right hand door or a left hand
door. For this purpose I fit in a circular hole or opening in the end of the latch
or lock case a disc which is free to be rotated therein when not held by a catch.
This disc has a rectangular hole to give passage to the bevelled end of the latch
bolt;
this bevelled end is not rigidly fixed to the bolt but is free to be rotated
thereon with the disc aforesaid. The disc is formed with two notches or recesses
at diametrically opposite points and in connection with these notches is a catch
which always takes into one or other of them. The catch is by preference a spring
attached to the inside of the end plate. If the bevelled end of the bolt is in
position for say a right hand door and it is required to apply the latch or lock to
a left hand door the catch is temporarily freed from the notch of the disc, the
bevelled end and disc are then moved half round on their axis by turning the
bevelled end by hand; the other notch of the disc will then be in position to
receive the catch and thereby hold the bevelled end in the reversed position, that
is to say, for a left hand door.
When my latches or locks are intended to be used as mortise latches or locks I
prefer to make the cases of tubular form because they will then fit into a round
mortise made by an auger; the tedious process of cutting a mortise as is required
for an ordinary rectangular mortise lock or latch is thus dispensed with. But as a
tubular case sometimes gives too limited a space for the lock mechanism I combine
the advantages of both tubular and rectangular cases by making a portion of the
tubular case viz: the part nearest the outside with upper and lower extensions so
as to afford sufficient height to receive the mechanism. After mortising out by
means of an auger a round hole such as would receive a tubular case it is easy to
widen the outer part of the hole by a chisel so that the upper and lower extensions
above described can fit therein.
In latch bolts which have a spherical ended latch or a latch in the form of a ball
or sphere carried in a cup within the case and which are used in connection with
corresponding striking plates or receivers on the door frame it has hitherto not been
possible to lock the latch by shooting the bolt forward beyond its normal position.
Now I construct spherical ended latch bolts which can be shot or withdrawn as
required by means of a key and the normal position of which is shot. On that
part of the bolt which is within the lock case (this case being by preference made
tubular) I form a stump to take into recesses and slots in a tumbler. In the normal
or shot position the bolt cannot be withdrawn because the stump is held by a
projection on the tumbler but when the key is inserted in the lock and turned the
tumbler is thereby raised freeing the bolt and the bolt is withdrawn to such an
extent that only the spherical end protrudes beyond the front plate; the door can
then be opened in either direction as with an ordinary spherical ended latch bolt.
The spring of the bolt is preferably a spiral spring fitted within a cylindrical part
of the bolt and bearing against a stop in the case.
I also make latch locks having the latch in the form of a sphere with the sphere
fitted in the striking plate instead of in the door, the said plate having behind it a
chamber to contain the spring this chamber being also capable of receiving the
whole of the sphere. The lock itself has a bolt with a concave recess in front to
receive the sphere. In the normal position the bolt does not project beyond the
front plate of the lock but when it is wished to prevent the lock being opened the
bolt is shot forward by means of any suitable lock mechanism so as to drive thé
sphere into the chamber behind the striking plate the bolt itself following it a
certain distance into the said chamber and thus locking the parts together.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Frederick James Biggs in the Patent Office on the 2nd April
1884.
FREDERICK JAMES BIGGS of Leadenhall Buildings in the City of London
"IMPROVEMENTS IN LATCHES AND LOCKS
"
Latches in which the bolts are capable of being locked by means of a key (and
commonly called "latch locks") have, as hitherto constructed, a great defect
namely that the handle by which the latch is drawn back cannot be turned or
moved when the latch is locked, the result of which is that persons apply great
force to the handle in the hope of turning or moving it and thus the latch
mechanism is liable to be strained and even broken.
Now in order to obviate this-defect I construct latches of the kind referred to in
such manner that they are locked by the latch being blocked or thrown forward
and simultaneously thrown out of gear or connection with the handle the handle
being thus free to be turned or moved but without acting upon the lock and that
when the latch is unlocked the handle is again put into gear, or connection
therewith so as when turned or moved to draw back the latch. I can effect this in
several ways. One modification is represented in Figures 1, 2 and 3 of the annexed
drawings. Figure 1 is a side view of the lock with the parts in their normal
position the side of the lock case being removed, Figure 2 is a similar view with
the latch locked or blocked and with the handle turned as in the act of opening
the latch. Figure 3 is a section on the line 1
1 of Figure 1. a is the
lock case, 6 the front plate, è the spindle of the handle taking into a square hole in
a sleeve or socket d which carries 2 horns or lugs e e; one of these lugs when the
handle is turned acts upon inclines ff on the back portion of the bolt. According
to the modification here shown I divide the bolt into 2 parts g and h to one of
which h the latch i is connected, while the other g is capable of being acted upon
by the handle as already stated. This part g carries a stump k which when the
latch is unlocked takes into a notch in a tumbler m connected by means of a pin
n with the part h which carries the latch i so that when the handle is turned the
whole of the parts are moved together; the spring o which surrounds the pin p
being compressed against the fixed stop q; when on the other hand the latch i is
locked the tumbler m which has been lifted and moved forward by the key
(inserted at r) in the act of locking, is free of the stump k so that when the handle
is turned it only moves the part g which carries the stump, the part h which carries
the latch not being affected. The latch is locked by a projection 8 on the tumbler
taking in front of a projection t on the lock case. In order to prevent any risk of.
the stump k and the tumbler blocking each other in case the latch is unlocked by
the key whilst the handle turned, I bevel the stump as shown and also the part
of the tumbler against which it strikes.
Another part of my invention consists of a mode of making the latch reversible
that is to say capable of being adapted to either a right hand door or a left hand
door. For this purpose I fit in a circular hole or opening in the front plate b of
the latch or lock case a disc u which is free to be rotated therein when not held,
by a catch. This disc has a rectangular hole to give passage to the bevelled end i
of the latch bolt, see Figure 4 which is a section on the line 2
2 of
Figure 1; this bevelled end is not rigidly fixed to the bolt h but is free to be,
rotated thereon with the disc u aforesaid. The disc is formed with 2 notches or
recesses w w at diametrically opposite points and in connection with these notches
is a catch which always takes into one or other of them. The catch is by.
--

page_text: preference a spring as shown attached to the inside of the front plate b. If the
bevelled end of the bolt is in position for say a right hand door and it is required
to apply the latch or lock to a left hand door the catch vis temporarily freed from
the notch w of the disc, the bevelled end and disc are then moved half round on
their axis by turning the bevelled end by hand; the other notch of the disc will
then be in position to receive the catch and thereby hold the bevelled end in the
reversed position that is to say for a left hand door.
The handle may be made to act in any ordinary manner but the novel
arrangement which I am about to describe and which is applicable not only to the
latch locks above explained but also to other latches is what I prefer in most cases,
Figures 5 and 6 represent this arrangement with the parts in two positions.
Figure 7 is a section on the line 8
3. Around the sleeve or socket d
through which the spindle o of the handle passes I form a toothed wheel x and
within the latch or lock case I fit 2 racks y y taking into the toothed wheel and
facing each other. Each of these racks has a claw to take on to a projection z¹
on the bolt g. Thus when the handle is turned, no matter in which direction, the
one rack is moved forward and the other backward-see Figure 6 that which
moves backward drawing back the bolt.
When my latches or locks are intended to be used as mortise latches or locks
I prefer to make the cases of tubular form as shown in the figures because they
will then fit in to a round mortise made by an auger; the tedious process of cutting
a mortise as is required for an ordinary rectangular mortise lock or latch is thus
dispensed with. But as a tubular case sometimes gives too limited a space for the
lock mechanism particularly when there is a lock separate from the latch I combine
the advantages of both tubular and rectangular cases by making a portion of the
tubular case viz: the part nearest the outside with upper and lower extensions so
as to afford sufficient height to receive the mechanism. This improved lock case is
represented in Figures 5, 6 and 7, A and B being the upper and lower extensions
to the tubular case a a. After mortising out by means of an auger a round bole
such as would receive a tubular case it is easy to widen the outer part of the hole
by a chisel or gouge so that the upper and lower extensions above described can fit
therein.
In latch bolts which have a spherical ended latch or a latch in the form of a ball
or sphere carried in a cup within the case and which are used in connection with
corresponding striking plates or receivers on the door frame it has hitherto not
been possible to lock the latch by shooting the bolt forward beyond its normal
position.
Now I construct spherical ended latch bolts which can be shot or withdrawn as
required by means of a key and the normal position of which is shot. This part of
my invention is represented in Figures 8 and 9, Figure 8 shewing the parts in
their normal positions while Figure 9 shews them in the positions they occupy
when the bolt is withdrawn. a is the bolt and b its spherical end which is kept
shot by the spring c. On that part of the bolt which is within the lock case (this
case being by preference made tubular) I form a stump d to take into recesses and
slots in a tumbler e. In the normal or shot position Figure 8 the bolt cannot be
withdrawn because the stump d is held by a projection f on the tumbler e but
when the key is inserted in the lock and turned the tumbler is thereby raised
freeing the bolt and the bolt is withdrawn by the key to such an extent that only
the spherical end protrudes beyond the front plate; the stump d being now held
back by the other side of the projection f the door can then be opened in either
direction as with an ordinary spherical ended latch bolt. The spring c of the bolt
is preferably a spiral spring as shewn fitted within a cylindrical part of the bolt and
bearing against a stop g in the case. Figure 10 is a section on the line 4
of Figure 8.
I also make latch locks having the latch in the form of a sphere with the sphere
fitted in the striking plate instead of in the door. Figures 11 and 12 represent this
part of my invention, a being the sphere fitted in the striking plate b; this plate

page_text: has behind it a chamber d to contain the spring e this chamber being also capable
of receiving the whole of the sphere a. The lock itself has a bolt f with a concave
recess g in front to receive the sphere. In the normal position shown in Figure 11
the bolt does not project beyond the front plate h of the lock but when it is
wished to prevent the lock being opened the bolt is shot forward, see Figure 12, by
means of any suitable lock mechanism so as to drive the sphere a into the
chamber d the bolt itself following it a certain distance into the said chamber and
thus locking the parts together.
Having now described the nature of my said invention and in what manner the
same is to be performed I declare that I claim as my improvements in latches and
locks:
1. Constructing latches of the kind commonly called "latch locks" in such manner
that when the latch is locked it is thrown out of gear or connection with the
handle which is thus free to be moved or turned without acting upon the latch
substantially as and for the purpose herein before described.
2. The particular arrangement substantially as herein before described and repre-
sented in Figures 1, 2 and 3 whereby when the latch is locked it is thrown out of
gear or connection with the handle which can then be moved or turned without
acting upon the latch.
3. The mode or method herein before described and represented in Figures 1, 2
and 4 of making latches reversible.
4. The novel arrangement substantially as herein before described and represented
in Figures 5, 6 and 7 by which the handle is made to act upon the bolt of latches
or locks.
5. Constructing mortise latches or locks with tubular cases having extensions or
enlargements at the part nearest the outer end substantially as hereinbefore
described and represented in Figures 5, 6 and 7.
6. Constructing spherical ended latch bolts substantially as hereinbefore described
and represented in Figures 8, 9 and 10 so that the bolt can be shot or withdrawn
by means of a key.
7. Constructing latch locks with the latch in the form of a sphere fitted in the
striking plate and so arranged that when the bolt is shot it drives and follows the
sphere into a chamber behind the striking plate substantially as hereinbefore
described and represented in Figures 11 and 12.
In witness whereof I the said Frederick James Biggs have hereunto set my
hand and seal this twenty ninth day of March One thousand eight hundred and
eighty four.
F. J. BIGGS. (L.S.)