IMPROVEMENTS IN AUTOMATIC LATCHES OR FASTENING BOLTS
Year: 1875

page_text: LETTERS PATENT to William McGeoch, junior, of Glasgow, in the
County of Lanark, North Britain, Ironmonger, for the Invention
....…
PROVISIONAL SPECIFICATION left by the said William Mc Geoch
at the Office of the Commissioners of Patents, with his Petition,
on the 18th November 1875.
I, WILLIAM MCGEOCH, junior, of Glasgow, in the County of Lanark,
North Britain, Ironmonger, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN AUTOMATIC LATCHES OR FASTENING BOLTS,"
to be as follows, that is to say :-
This Invention has for its object the constructing and arranging of
automatic latches or fastening bolts in an improved and superior manner,
and so as to avoid the inconvenience of the angular projection of the
ordinary latch bolt.

page_text: The improved fastening is advantageously adapted for doors, drawers,
or anything to which the ordinary latch bolt is or may be applied.
The latch or fastening bolt is by this Invention made without the
usual bevilled or angular point, its end being rectangular or slightly
rounded, but it is arranged to be drawn inwards or from the striking
and holding plate of the door frame or other frame, either by a follow
acted on by a handle in the more common way or by any known
arrangement of handle or key and connections. The latch is arranged
in connection with one arm of a two-armed lever, to the other arm of
which there is jointed a stud having its end projecting through the lock
case or door edge, but only to a comparatively small extent, the outer
end of the stud being rounded so as not to catch on dresses or other
things passing the door edge. When the door is closed the projecting
stud encounters the striking plate of the door frame, or if necessary a
projection is formed or fixed on the striking plate should the door not
fit the frame closely. The stud is pushed in by the act of closing the
door, and in doing sc it, through the reverse action of the two-armed
lever, causes the latch to move outwards and into the hole for it in the
striking plate. When the improved latch is fitted to ship's cabin doors,
railway carriage doors, or wherever there is risk of shaking, which
might possibly throw the latch back, a catch is additionally provided to
enter a notch or behind a pin on the latch bolt when it is fully shot out,
and prevent the bolt returning until the catch is released by the action
of the handle.
Another improvement consists in applying a double acting spring to

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eighteenth day of November, in
the year of our Lord One thousand eight hundred and seventy-five,
in the thirty-ninth year of Her reign, did, for Herself, Her heirs
and successors, give and grant unto me, the said William McGeoch,
Her special licence, that I, the said William McGeoch, my executors,
administrators, and assigns, or such others as I, the said William
M°Geoch, 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 AUTOMATIC LATCHES, OR FASTENING BOLTS,"
upon the condition (amongst others) that I, the said William McGeoch,
my executors or administrators, by an instrument in writing under
my, or their, or one of their hands and seals, should particularly
describe and ascertain the nature of the said Invention, and in what
manner the same was to be performed,, and cause the same to be
filed in the Great Seal Patent Office within six calendar months next
and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said William M'Geoch, do hereby
declare the nature of my said Invention, and in what manner the
same is to be performed, to be particularly described and ascertained.
in and by the following statement in writing, reference being had to
the accompanying Drawings, that is to say:-
My said Invention has for its object the constructing and arranging of
automatic latches or fastening bolts in an improved and superior manner,
and so as to avoid the inconvenience of the angular projection of the
ordinary latch bolt.
My improved fastening is advantageously adapted for doors, drawers,
or anything to which the ordinary latch bolt is or may be applied.
The latch or fastening bolt is by my Invention made without the
usual bevilled or angular point, its end being rectangular or slightly
rounded, but it is arranged to be drawn inwards or from the striking
plate of the door frame or other frame, either by a follow acted on by a

page_text: handle in the more common way, or by any known arrangement of
handle or key and connections. The latch is connected to one arm of a
two-armed lever, to the other arm of which there is jointed a stud or
spindle, having its end projecting outside of the lock case or door edge,
but only to a comparatively small extent, the outer end of the stud or
spindle being rounded so as not to catch on dresses or on anything
moved past the door edge. On closing the door the projecting stud
encounters the striking plate of the door frame, or if necessary a
projecting guide is formed or fixed on the striking plate should the
door not fit the frame closely enough. The stud is pushed in by the act
of closing the door, and in moving- in it through the reverse action of
the two-armed lever and of a spring which it compresses, causes the
latch to move outwards as soon as it gets fairly opposite the hole
provided for it in the striking plate.
Another improvement consists in applying a double-acting spring to
the follow to insure its always returning to its neutral position in-
dependently of the latch."
And in order that my said Invention and the manner of performing
the same may be properly understood, I hereunto append a Sheet of
explanatory Drawings to be herein-after referred to, and representing
various modifications of my improved automatic latch details. In these
Drawings the same reference numerals are used to mark the same or
like parts wherever they are repeated.
Figure 1 is a view of a mortise door lock with the covering plate
removed. The latch bolt 1 is formed with a shank 2, which is connected
to the longer arm 3 of a two-armed lever 3, 4, centered on a fixed pin 5,
the connection between the bolt shank 2 and lever arm 3 being made
by means of notches in the bottom edge of one and in the upper edge
of the other. The short arm 4 of the lever is connected to a spindle 6,
which has fixed on its front end by screwing, so as to be capable of
adjustment, a stud 7 which projects to the outside through a hole in the
face plate 8 of the lock, and has its outer end rounded. The stud
spindle 6 is formed with a small cross head at its back end with angular
edges to bear in an angular notch on the lever arm 4, the spindle itself
passing forward through a hole in the middle of the lever arm.
part the stud spindle 6 is squared or flattened to move backwards and
At one
•

page_text: forwards without turning in a guide slot in a piece 9 fixed to the back
of the lock, and between this guide piece 9 and the stud 7 there is put
on the spindle 6 a helical spring 10, which moves the stud 7 outwards
when the door is opened, and at the same time keeps the latch bolt 1
withdrawn within the lock. A second spring 11 is put on the spindle 6
so as to act between the front side of the lever arm 4, and a cross pin or
equivalent fixed in the spindle itself, and this spring 11 is compressed
during the time the stud 7 is being pushed in when closing the door
until the door is sufficiently closed for the bolt 1 to enter the hole for
it in the striking plate 12. The striking plate 12 is shown in edge view
in Figure 1, and in face view in Figure 2, and in general it will be made
as shown with a slightly projecting contact or guide piece 13 for the stud
7 to meet. In order that the stud 7 may when full out project to only a
small extent, and yet act effectively, the latch bolt 1 is moved in for
opening the door by means of the usual follow 14, which is arranged
to act on the lever arm 3, but a double acting blade spring 15 is fixed
in the lock, so as to act on a projection on the front of the follow and
return it to its neutral position independently of the two-armed lever 3,
4, and other parts. The lock, Figure 1, is shown as provided with the
usual additional bolt 16, to be acted on by a key.
Figure 3 shows a simplified modification, in which the spring 10 for
moving the stud 7 outwards is placed between the back end of the stud
spindle 6 and the back of the lock, whilst the other spring 11 is applied
between the lever arm 4 and the stud 7. In Figure 3 the parts are
shown in positions assumed when the door is closed.
Figure 4 shows a modification with a third mode of arranging the
springs 10, 11, both being made to bear against a fixed piece 9, one
backwards and the other forwards. In this case the spring 10 for
moving the stud 7 has to be strong enough to overcome the spring 11
acting in the opposite direction, and the modifications in which the
springs act independently of each other are to be preferred.
Figure 4 further shows an addition which may be made to any of the
modifications, and which consists of a catch lever 17 acted on by a
spring, so as to engage behind a projection 18 of the bolt shank 2, and
hold the bolt 1 out when shot. This addition may be fitted with

page_text: advantage to ships' cabin doors, railway carriage doors, or wherever
there is risk of shaking, which might possibly throw the latch back.
When opening the latch the end of the lever arm 3 notched or slotted
for the purpose acts on the heel of the catch lever 17, and first moves
it out of the way before drawing in the latch 1, a little play being
allowed between the shank 2 and lever arm 3 to admit of it.
Figures 5 to 9 show various modes of applying the springs. In
Figures 5 and 6 two blade springs 10, 11, are applied; in Figure 7 the
lever 3, 4, is itself a spring bent round the centre pin 5; in Figure 8
the two arms 3, 4, of the lever are hinged together, and a blade spring:
is fixed to them to tend to bring them into a straight line with each
other, and in Figure 9 two springs 10, 11, are formed by the two free
ends of a single blade, held by a pin 19.
In the modifications shown in Figures 7 and 8 a spring 10 has to be
applied on the stud spindle 6, as in Figure 1.
Figure 10 shows a modification of my improved automatic latch lock
suitable for railway carriage doors. An internal latch 20 is fixed on the
handle spindle instead of a follow, and a volute spring 21 is applied to
turn it down behind the latch bolt 1, whenever this bolt is shot out by
the action of the stud 7 on closing the door, thus acting like the catch
lever 17, shown in Figure 4. When the handle is turned to open the
door the latch 20 acts on a projection on the lever arm 3. With this
arrangement a railway guard will see by the position of the handles
whether the carriage doors are properly fastened or not.
Having thus particularly described my said Invention, and the
manner of performing the same, I have to state that I do not restrict
myself to the precise details herein described or delineated, but that
what I believe to be novel and original, and claim as the In-
vention secured to me by the herein-before in part recited Letters
Patent is,―
1. The combination of the latch bolt (1), two-armed lever (3, 4,),
stud (7), and springs (10, 11,), substantially in the manner and for the
purposes herein-before described.
2. The combination of the catch lever (17) with the other parts,

page_text: 3. The combination, of the double acting spring (15) with the
follow (14), substantially as and for the purpose herein-before described.
In witness whereof, I, the said William McGeoch, have here-
unto set my hand and seal, this Sixteenth day of May, in the
year of our Lord One thousand eight hundred and seventy-six.
Witness,
EDMUND HUNT,
Patent Agent,
Glasgow.
W. M GEOCH, JUN'. (L.S.)