IMPROVEMENTS UPON LATCHES AND BOLTS EMPLOYED IN LOCKS AND OTHER FASTENINGS
Year: 1860

page_text: PROVISIONAL SPECIFICATION left by James Brodie at the Office of
the Commissioners of Patents, with his Petition, on the 24th April
1860.
I, JAMES BRODIE, of Bow of Fife, in the County of Fife, North Britain,
Clerk, do hereby declare the nature of the said Invention for "IMPROVEMENTS
UPON LATCHES AND BOLTS EMPLOYED IN LOCKS AND OTHER FASTENINGS," to be
as follows:-
My Invention is intended to accomplish the two objects which are more
especially to be desired in all fastenings, that is to say, fastening easily and
holding securely.
The first part of my Invention is intended to facilitate the operation of
fastening, and is more particularly applicable to latches, that is to say, to
fastenings which are connected with handles, though it may also be applied
to bolts, that is to fastenings, which are acted on by keys.
The second part of my Invention is intended to combine security of holding
with compactness of form, and is more particularly applicable to bolts, though
it may also be connected with latches; the two parts of my Invention may be
employed separately, but in many cases a combination of both will be required.
The first part of my Invention, which I shall call the latch catch, consists in
the employment and more particularly in the combination of two peculiarities-
of construction.
In the first place, in addition to the latch I employ a catch, which has an

page_text: independent motion of its own, so that it can be pushed aside and allow the
door to be shut without moving the latch. At the same time it is so con-
nected with the latch, that on moving the latch the catch is loosened from its
-hold and-allows the door to be opened. One end of this catch is affixed either
to the door or to the door post, as the case may require, by means of a pia or
joint or flexible spring on which it moves. The other end moves freely.
When the door is being shut the moveable end is lifted up or pushed aside
by coming into contact with a keeper or check, or some projection. This
keeper is connected with the door when the catch is fastened to the door post,
and is connected with the door post when the catch is affixed to the door.
This keeper or check is so formed that when the door is completely closed,
the catch being acted on either by its own weight or by a spring, falls in
behind the keeper and by taking hold of it makes the fastening secure.
When the door is to be opened the latch is moved by the handle and being
made to act on the catch loosens it from its hold and permits the door to
be opened.
In the second place I enclose that end of the catch by which it is affixed
either to the door or to the door post, as the case may be, with a protecting
plate of metal while the other or moveable end is left exposed.
These peculiarities may be exhibited in a variety of forms, as for example,
in catches with a projection behind, in catches with a projection at the sides,
and in catches acted on by springs. In catches with a projection behind, the
outer or moveable end is made in the same form as the staple or keeper
usually employed in holding the latches of cottage doors, that is to say,
that part of the catch on which the latch presses when the door is being
closed is sloped away, so as to form an inclined plane, and this sloping part
is afterwards. made to terminate abruptly, so that the latch falls in behind
it, and thus fastens the door.
In my Invention, the catch, instead of being immoveably fixed to the door
post is fastened to a plate of metal by means of a pin on which it moves.
freely. When the sloping point of the catch points upwards that part of the
catch which is behind the pin is made of such a length, and size that by its
weight it keeps up the projecting part of the catch so that it may be acted on by
the latch when the door is being shut. This form of the moveable catch is shewn
in Figure First. When the sloping part of the catch points downwards the outer
or moveable part is made the heavier, and falls down with its own weight.
The projection behind, which is within the plate, regulates the motion of the
catch, and by coming into contact with a pin fixed in the plate prevents the outer

page_text: part of the catch from falling too low; this form of catch is shewn in Figure
Second. In catches with a projection at the side, while the end by which they
are attached is covered by a plate of metal, the moveable. end has a projection
at the side which passes through an opening made for it in the plate. The
lower side of this projection is sloped away, and by this means when the door
is being shut the catch is lifted up in consequence of its coming into contact
with a corresponding projection, either from the door or door post, as the case
may require. The projection from the catch terminates abruptly, so that when
the door is completely closed the catch falls down again and fastens the door.
Figures Third, Fourth, Fifth, and Sixth represent some of the many forms
in which this variety of catch may be made. In catches acted on by springs.
the moveable end projects through an opening made for it in the covering
plate, while the part behind is acted on by a spring. When pressure is
applied to it, the moveable end is pushed back; when the pressure is removed
the elasticity of the spring brings it out again into its former position. When
these catches are fastened to the door, a bent or hooked projection behind the
catch is fitted to a corresponing book at the end of the latch, which is drawn
back by the handle. When the door is being shut the catch alone is moved;
when the door is to be opened the latch is drawn back, and the catch along with
it. Figure Seventh represents one form out of many in which this catch may
be made. When these catches are fastened to the door post they may either act
directly on the latch, in this case the latch is withdrawn in order to allow
the door to be opened, or they may fall into a notch prepared for them, and act
against a fixed part of the door or lock, in this case the latch is made to push
back the catch, and thus disengages it from its hold when the door is to be
opened. Figure Eighth represents one form of this catch.
The second part of my Invention, which I propose to call the catch and
keeper bolt, includes two peculiarities of construction; in the first place I attach
to the lock one or more catches or tumblers which fit into a keeper connected
with the bolts. This keeper consists of a piece or pieces of metal, and has two
arms or projecting parts, the ends of which come near to each other, the keeper
is rivetted or otherwise fastened to the bolt, or the bolt and keeper aro made all
of one piece. The catch or tumbler consists of a small bar or piece of metal
which moves on a pin attached to the lock. One end of this catch is made of
such a size that while it enters easily between the arms of the keeper it at the
same time fills up very nearly the entire space left between them. This
keeper and catch are so placed in regard to each other that when the bolt is
pushed out for the purpose of locking the door, drawer, or lid, which it is

page_text: intended to fasten, the catch is drawn out from between the arms of the
keeper and is pushed to a side either by the action of a spring or by its own
weight; the bolt therefore cannot be drawn back unless the catch be put into
such a position that it enters again between the arms of the keeper. In order
that the catch may be brought into this position, that part of it which is nearest
the key is cut into the form of an are which corresponds to the circle described
by a projecting part of the key. When the key is turned round the action of
this projecting part brings the catch into the proper position before the key
begins to act upon the bolt. The more numerous the catches are the greater
security will be given to the lock; notches are cut in the keeper and corre-
sponding projections are made at the end of the catch in order to prevent the
bolt from being pushed back without employing the appropriate key. The
second peculiarity in the construction of my bolt, and this is the part which I
more particularly claim as my own Invention, consists in placing the catch or
catches so that they are acted on by projections on one part or side of the key,
while the bolt is acted on either by a projection from another part or side of
the key or by a handle. The pin on which the catches move may be placed
either towards the end of the catch or towards the middle of it. The catches
may be acted on either by their own weight or by a spring. When the lock is
exposed to damp and the catches to rust, the back part of the catch may be
made of a forked form so as to be acted on by projections from both sides of
the key and brought into the desired position without the action either of its
own weight or of a spring. Figures Ninth, Tenth, and Twelfth, represent
bolts of the construction which I have described.
The two parts of my Invention may be used separately, they may also be
combined in various ways; for example, in the same lock there may be a latch
with a catch such as is described in the first part of my Specifications, along
with the bolt described in the second part of them; or the catch and keeper
bolt may be used in connection with the latch catch, so that it may be
fastened by simply pushing back the door or lid without using the key; or the
same fastening may serve at once as a bolt and a latch and have applied to it
both parts of my Invention, as shewn in Figure Thirteenth.
In order that my Invention may be fully understood, I shall proceed to
describe it more particularly by the aid of the accompanying Drawings, in
which are represented some of the varied forms in which latches and bolts
may be made in accordance with the principles herein-before referred to.
The catch with a projection behind is represented in Figures First and
Second; d, b, c, is the outer end of the catch; a is the pin on which it moves;

page_text: P, P, P, is the plate to which it is affixed; a, e, is the projection behind
which comes into contact with the pin g. The catch with a projection
at the side is represented in Figures Third, Fourth, Fifth, and Sixth. Figure
Third represents a catch affixed to the door, the plate p, p, p, forming part
of the lock. The catch a, d, b, c, is affixed to this plate by means of the
pin a on which it moves; the part a, d, represented by the dotted lines, lies
within the plate d, b, c, is the projection at the side, and passes through
the opening g, h, d, c, cut for it in the plate. A projection on the opposite
side at e lies above the end of the latch, by means of which it is lifted
up when the door is to be opened. Figure Fourth represents the horizontal
section of a catch in which the projection is formed by bending the catch
into a double knee at e and d. Figure Fifth represents a double catch formed
in the same manner as that shewn in Figure Fourth, which is intended to be
fastened to the post, when a door or gate is made to open in either direction.
p. p, p, is the plate; a, d, b, c the catch; d, b, c, the projection at the side; e, g,
is the opening cut in the plate; is the latch, which by pressing on b, c, the
under side of the catch raises it up when the door is being shut. When
the door is to be opened, the latch is lifted up, and passes over the top of
d, b. Figure Sixth represents another variety of this kind of catch. Catches
acted on by a spring are represented in Figures Seventh and Eighth. In
Figure Seventh the catch a, b, c, moves horizontally. A projection a, g, is
acted on by a springs, which makes the catch stand out beyond the plate p, p, p,
When the door is being shut, the side a, c, of the catch presses against the
projection d, and is thus pushed back; when the door is completely closed it
starts back into its former position and by pressing against the back part of d, it.
keeps the door secure. When the catch is affixed to the door a bent pro-
jection at b, b, is acted on by a corresponding hook or projection e affixed to the
latch, and the latch being moved by the handle, the catch is drawn back and
allows the door to be opened. When this form of catch is affixed to the door post,
I either make the projection d moveable, or I push back the catch in the
manner represented in Figure Eighth. In Figure Eighth a, b c, is a catch
affixed to a spring 8, 8, and passing through a hole in the plate p, p; r, r, is
the usual wooden cheek against which the door comes when it is closed; e, f
is the edge of the door, having a notch e, d, f, cut in it to fit the catch a, b, c,
When the door is being shut, the part of the door or lock at e presses against.
b, c, and pushes back the catch. When it is completely closed, the catch
resumes its former position, so that c, d, occupies the space r, a, c. When
the door is to be opened, the end of a latch m is pushed out and presses

page_text: back the catch. The catch may be made to move on a pin at b, and the
springs, s, s, instead of being fixed to the catch, may be made separate from
it, and lie along a, b, the back of the catch.
Figure Ninth represents a bolt of the construction which I employ when
the bolt and catches are on the same side of the key-hole; a, b, c, repre-
sents the bolt; e, e, is a slit or opening, such as are commonly made, for
keeping. the motion of the bolt in a straight line; d is the pin on which it
slides; m, g, h, b, c, is the keeper, which is rivetted or otherwise fastened to
the bolt; d, f, is the catch moving on the pin d; m and h are the two arms
between which the end f, of the catch or catches enters.
The bolt is repre-
sented by the dotted lines, the catch is drawn in black lines, and is shewn
in the position which it assumes when the bolt is half way out. Figure
Tenth represents one variety of the bolt which I employ when the catches
lie on one side of the key, and that part of the bolt on which the key acts
lies on the other; 9, f, n, represents the bolt of which the keeper a, b, c, d, e, k,
forms the upper part. The catch l, m, moving on the pin /, fits into c, d, e, k,
the opening made for it in the keeper. Another catch moving on the same
pin and likewise fitting into c, d, e, k, is represented by the dotted lines.
o is a piece of metal fastened to the lock, the upper part of it fitting into a
notch or opening cut for it in the catch and is intended to prevent any
attempt at picking the lock. The catches may be pressed downwards
either by their own weight or by the action of a springs; h, is the keyhole.
When it is intended to mako the lock so that it may be opened from either
side of the door, the projections on the one side of the key are fitted for lifting
the catches when the lock is opened from within, while those on the other
side are fitted for lifting them when it is opened from without. As each side
of the key has in its turn to lift the catches and to act on the bolt, the longest
of the projecting parts that lift the catches must be of sufficient length to act
on the bolt. The projecting parts of the key occupy what may be termed an
inverted position on the opposite sides, as is shewn in Figure Eleventh. The
end of the bolt at 9 may be prolonged, and be employed as the part which
projects and secures the door; the other arrangements will remain as in
Figuro Tenth. In this case the keeper a, b, c, d, k, e, f, will occupy the back
part of the lock, and the pin will be in front. Figure Twelfth represents
another variety of the catch and keeper bolt of a form and size suitable for
cupboards and closets. In it the pin is nearly in the middle of the
catch. Figure Thirteenth represents a fastening which is at once a latch
and a bolt, and in which the different parts of my Invention are combined;

page_text: a, b, c, is the bolt; c, e, e, b, is a notch into which a catch falls, such as is
shewn in Figure Eighth; h is the handle by which a, b, c, is pushed out; 5, 8,
is a spring by which it is brought back; l, m, is the catch; is the inside key,
which, when it lies flat, allows the bolt to move freely, but which when raised
lifts the catch l, m, and thus prevents the motion of the bolt a, b, c; is tho
outside key, which is kept erect by a spring like that of a pocket knife, and
while it remains erect it keeps the catch 7, m, in such a position that it enters
the opening m, d, and allows the bolt to move. When this key is turned
round or taken away the catch falls down and prevents the movement of the
bolt.
In fastening on the handles I make the spindle or rod that passes through
the latch of two pieces, which, when put together, form a four-sided bar that
fills up the opening in the neck of the handle. One end of each piece has a
head or projection on one side, so that while it may be pushed up into the
handle by itself, it cannot be pushed up or taken out unless the other piece be
away. The head part of the rods having been put one into cach handle, the
other ends are then pushed through the latch and door and up into the opposite
handle so far as may be required. The rods having been fixed together by
screws, the heads within hold the handles together.
Having thus described the nature of my Invention and the manner in which
the same is to be carried into effect, 1 shall now state the particulars which I
claim as peculiarly my own Invention; they are as follows:-
First, I claim as my own Invention the employment of a latch catch, as
described in the first part of my Specifications, which, in the first place, has
an independent motion of its own, so that while it may also be moved by the
latch it can be moved by itself and allow the door to be shut without moving
the latch; and which, in the second place, is so constructed that the end by
which it is affixed, whether to the door or to the door post, is covered with a
protecting plate of metal, while the other or moveable end is left exposed.
Secondly, I claim the various forms in which this latch catch may be made,
as described in my Specifications.
Thirdly, I claim as my own Invention the employment of the catch and
keeper bolt, as described in the second part of my Specifications, that is, of a
bolt having attached to it the contrivance which I call a keeper, while the
catch or catches which fit into this keeper, and which are connected with the
lock by means of a pin on which they move, are acted on by projections from
the key. More particularly I claim as my own Invention that variety of the
catch and keeper bolt in which the catches are acted upon by projections on

page_text: one side or part of the key, while the bolt is pushed out or drawn in by means
of a projection on another part of the key, or by means of a handle.
Fourthly, I claim the various forms of this catch and keeper bolt, as de-
_scribed in my Specifications.
Fifthly, I claim the various forms and means in and by which the two
parts of my Invention may be combined, as described in my Specifications.
Sixthly, I claim as my own Invention the method of affixing the handles, as
described in my Specifications.