Improvements in Latches for Doors and the like.
Year: 1893

page_text: Date of Application, 2nd Sept., 1893
Complete Specification Left, 20th Nov., 1893-Accepted, 23rd Dec., 1893
PROVISIONAL SPECIFICATION.
Improvements in Latches for Doors and the like.
I HARRY JOHNSON MACKLIN of Lightburn Road, Ulverston in the County of
Lancaster, Engineer, do hereby declare the nature of this invention to be as
follows:-
This invention relates to improvements in that class or classes of latch
respectively known by the names of Lancashire, Norfolk or Suffolk latches the
object being to render such latches free from that excessive friction which has
usually accompanied their working hitherto, by means of an improved construction.
As is well known this class of latch is usually composed of a bow shaped handle
attached to one side of the door with a thumb lever passing through the top of the
handle and the door and supporting on the opposite side of the door a catch lever
or fall bar. The latter is usually pivoted by one end to the door whilst its other
end passes through a bracket or keeper and engages with a catch fixed to the
framework which surrounds the door. Now in closing the door with this class of
latch attached, a great amount of friction is set up, immediately the under side of
the fall bar begins to mount the inclined end of the catch, such friction continuing
until the fall bar drops behind the catch and the door is fully closed. Not only is
there friction between the fall bar and the catch but also between the fall bar and
the keeper or bracket through which it passes.
In order to avoid these defects I pivot the fall bar to the door at a point
intermediate of its ends preferably with one end nearer to the point of suspension
than the other. I preferably allow the shorter end to project beyond the edge of the
door whilst the long end passes through an ordinary keeper or bracket. Instead of
using a catch fixed immovably to the frame surrounding the door I pivot the catch
thereto so that its outer end may rise and fall the neb or catch proper projecting
downward instead of upward as is the case in the latches before referred to. When
closing a door fitted with a latch as described the fall bar retains its horizontal
position and on coming into contact with the catch lifts it until the door is
completely closed when the catch falls down and retains the door in position. With
this class of latch the door could only be opened from the inside, but in order that
it may be opened from the outside as well I make use of an ordinary thumb lever
and handle the former passing beneath the fall bar at the point situated between its
fulcrum and the keeper or bracket. The keeper whilst allowing the longer end of
the fall bar to move upwards in ordinary cases is provided with a hole situated
above the top edge of the fall bar when the latter in its horizontal position, and a
pin may be passed through this hole or other means may be provided to lock the
fall bar in position and thus prevent the door being opened from without.
One of the great advantages of this latch over others is that of being able to
secure the fall bar before closing the door thus answering the purpose of a night
latch. By this means a person leaving his or her house early in the morning may
by simply inserting the pin before closing the door, leave the house secure from
intruders.
Dated this 1st day of September 1893.
Per pro EMMOTT & CO., LIMITED,
Robert Wood, Secretary,
2, New Bridge Street, Manchester, and 85, Strand, Loudon,
Agents for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in Latches for Doors and the like.
I, HARRY JOHNSON MACKLIN of 49 Lightburn Road, Ulverston, in the County
of Lancaster, 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 :-
" 66
This invention relates to improvements in that class or classes of latch
respectively known by the names of "Lancashire,' Norfolk," "Suffolk" or
"Gothic" latches, the object being by means of a new construction to render such
latches free from the excessive friction which has hitherto usually accompanied
their working.
As is well known, this kind of latch is generally used with a bow shaped handle
attached to one side of the door with a thumb lever passing through the top of the
said handle and the door, and supporting, at the opposite side of the door, the catch
lever or fall bar. The latter is usually pivotted by one end to the door whilst its
other end passes through a bracket staple or keeper and engages with a catch fixed
to the framework which surrounds the door. Now in closing a door with this class
of latch attached a great amount of friction is set up immediately the underside of
the fall bar begins to mount the inclined end of the catch, such friction continuing
until the fall bar drops behind the catch and the door is finally closed.
Not only
is there great friction between the fall bar and the catch but also between the fall
bar and the keeper or bracket through which it passes.
In order to avoid these defects I pivot the fall bar to the door at a point
intermediate of its ends, preferably with one end nearer the point of suspension than
the other but in any case in such manner that the end furthest from the catch is
sensibly heavier than the other end. I preferably allow the shorter or lighter end
to project beyond the edge of the door, whilst the long or heavier end passes
through an ordinary keeper or bracket. Furthermore instead of using a catch
fixed immovably to the frame surrounding the door I pivot the catch thereto so
that the outer end may freely rise and fall, the neb or catch proper projecting
downward instead of upward, as in the case in the latches before referred to.
When closing a door fitted with a latch as described by simply pushing or pulling
the door to, without operating the latch by the hand, the fall bar retains its
horizontal position and on coming into contact with the catch lifts such catch until
the door is closed when the catch falls down and retains the door in position. In
order that the door may be opened from the outside as well as from the inside
I may make use of the ordinary thumb lever and bow handle the former passing
beneath the fall bar at a point situated between its fulcrum and the keeper or
bracket.
The keeper whilst normally allowing the longer or heavier end of the fall bar to
move upwards may be provided with a hole situated above the top edge of the fall
bar, when the latter is in a horizontal position and a pin may be passed through
this hole to lock the fall bar in position and thus prevent the door from being
opened from without. Or the hole may be so placed that the pin passes through
the fall bar as well as through the keeper.
In the accompanying drawings I have shown some examples of my latch, but
I will premise that I have only shewn a few modes of operating the fall bar because
the essence of my invention consists in the construction of the fall bar itself in
conjunction with a pivoted catch as described and because the modes operating the
fall bar will depend upon many circumstances sometimes according to the dictates
of mere taste or fancy and accordingly also involving alterations in the form of the
latch without departing from my invention.
Figure 1 is a front view and Figure 2 a vertical section of my latch in a simple

page_text: and useful form as applied to a door and to be operated by an ordinary thumb
lever and handle. The fall bar is in the form of a double armed lever so pivoted
on the door at A* that the catch end A2 is sensibly shorter or lighter than the
opposite end A' which latter is guided in a staple or keeper B on the door. The
fulcrum pin at A* may be a common wood screw screwed into the door and having
a washer on each side of the fall bar. The catch C is pivoted to the door frame
with the neb downwards. It will be seen that its fulcrum is below (or it may be
in a line with) the angle C of the catch; if the fulcrum were above that angle or
corner the catch would have a tendency to lift or be thrown into an upright
position when the fall bar is pushed against it and thus become inoperative. But
with the arrangement shewn the end A2 of the fall bar, in closing the door by
merely pushing or pulling it into the closed position, will come into contact with
the under part of the neb end of the catch C and cause such catch to rise till the
fall bar has passed the point Cx on the under part of the neb end of catch when
such catch will drop and hold the door in the closed position shewn. D is a usual
bow handle with lever D¹ for opening the latch from the outside or the inside.
B is a hole in the keeper or staple B, and E is a peg attached by a chain or the
like and adapted to be inserted in the hole if desired to lock the latch from the
inside of the door in the closed position. Or a wedge may be inserted between the top
Or
of the fall and the underside of top of keeper for locking or fixing the fall bar.
the hole B' may as shewn in dotted lines pass through the fall bar in the closed
position of the latter.
Figures 3 and 4 shew the catch applied to a plate with two fulcrum holes so as
to be applicable for doors hung from the right or left side according as one hole or
the other is used.
Figure 5 shews the fall bar A¹ A² applied to a usual rim latch arrangement where
the end A¹ of the fall bar is raised by a follower or tumbler D' having a knob
handle on its fulcrum pin Dx. In this form the casing itself serves as keeper.
A spring might be used to ensure or assist the fall bar bearing with sufficient force
on either end of the follower to overcome the friction.
"
Figure 6 shews a latch adapted to be opened by a tumbler D with "Gothic'
handle D2 on one side as shewn in dotted lines and a round knob F on the other
side.
Figure 7 shews a latch in which the keeper B is fitted with a follower or
tumbler D' on a square fulcrum pin D* the latter being on each side of the door
provided with a knob or handle of any suitable form for operating the tumbler.
Figure 8 shews a latch in which a handle D2 on each side of the door is attached
to the fulcrum pin A of the fall bar for operating it; this is however not so
advantageous, as the bandle can only move one way, whereas if fitted with tumbler,
as in the three previous examples, the handle can be moved either to the right or
to the left and yet have the same effect, namely that of raising the end A¹ of the
fall bar. The handle in Figure 8 acts as an additional weight in bringing the fall
bar back to its normal horizontal position.
In garden gate latches where round handles are used the square fulcrum spindle
would pass right through and the heavy end A' of the fall bar would be greatly in
excess of the other so as to overcome the friction of the handle and return to its
normal horizontal position. The latch would be cased in as in the present rim
latch and the keeper B thus done away with, in fact the latch would be on
the principle shewn in Figure 5 but no spring would be used. The follower
however in this and other cases be made of such a shape and weight as shewn in
Figure 9 as by itself to overcome the friction.
Having now particularly described and ascertained the nature of my said inven
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. A latch for doors and the like in which the fall bar is made in the form of a
double armed unequally balanced lever of the first order the shortest or lightest

page_text: arm of which when the door is being closed presses upon the slanting neb of a
pivoted catch and raises it so that the fall bar can pass under the neb whereupon
the catch drops and holds it.
2. The constructions of latch with hinged catch shewn in the drawings.
Dated this 20th do of h 1000
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.