IMPROVEMENTS IN MECHANISM FOR FACILITATING THE REVERSAL OF THE BOLTS OF MORTISE AND RIM LOCKS AND LATCHES
Year: 1878

page_text: LETTERS PATENT to John Green, of Wolverhampton, in the County of Stafford,
Lock Manufacturer, for the Invention of "IMPROVEMENTS IN MECHANISM FOR
FACILITATING THE REVERSAL OF THE BOLTS OF MORTISE AND RIM LOCKS AND
LATCHES"
Sealed the 20th August 1878, and dated the 11th March 1878,
PROVISIONAL SPECIFICATION left by the said John Green at the Office
of the Commissioners of Patents on the 11th March 1878.
JOHN GREEN, of Wolverhampton, in the County of Stafford, Lock Manufacturer.
"IMPROVEMENTS IN MECHANISM FOR FACILITATING THE REVERSAL OF THE BOLTS OF
MORTISE AND RIM LOCKS AND LATCHES."
This Invention has for its object a simple arrangement for reversing the bolts of
mortise and rim locks and latches, without it being necessary to remove the cap
from the lock or latch.
The bolt is kept in gear with the mechanism for actuating it by means of a
metal screw passing through either the edge or the cap or plate of the lock or
latch.
According to one arrangement the tail of the bolt is formed with a recess on
opposite sides thereof, into one of which recesses the lock mechanism for actuating
the bolt gears. The said screw bears against the tail of the bolt and keeps it in
gear with the lock mechanism. When the screw is drawn back the said bolt may
be moved so that the recess is clear of the mechanism for actuating the bolt, and
may then be withdrawn and reversed. The opposite recess is then kept in gear
with the mechanism for actuating the bolt by again tightening up the screw.
tail of the bolt works against the screw.
The
According to another arrangement the bolt is made cylindrical, both at a recessed
part, where it gears with the mechanism for actuating the bolt, and also in the
head;
and the end of the screw (which is a plain cylindrical part) enters a slot,
Davine &77

page_text: formed through the tail of the bolt. When the screw is drawn back clear of the
slot, the bolt may be reversed by being simply turned a half revolution, the screw
being again advanced into the slot, and the bolt thus retained in its reversed
position. In the case of the second arrangement it is preferred to prevent any side
strain on the screw when the lock or latch is in ordinary use, by causing the spring
or other mechanism bearing against the back of the bolt (when such is the con-
struction of the mechanism) to gear into a V or similar shaped recess, so that the
bolt is kept from turning in ordinary use, but may be turned when the screw is
withdrawn, by sufficient force being used to cause the spring or other mechanism
to move up one of the inclined sides of the end recess as the bolt is turned, and thus
move out of the end recess, into which it springs again as the bolt is turned a half
revolution.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Green in the Great Seal Patent Office on the 6th September
1878.
JOHN GREEN, of Wolverhampton, in the County of Stafford, Lock Manufacturer.
"IMPROVEMENTS IN MECHANISM FOR FACILITATING THE REVERSAL OF THE BOLTS OF
MORTISE AND RIM LOCKS AND LATCHES.”
This Invention has for its object a simple arrangement for reversing the latch
bolts of mortise and rim locks and latches, without it being necessary to remove the
cap from the lock or latch.
According to this Invention the bolt is made cylindrical at the head, and also at
its connection with the crank or corresponding mechanism, and is made preferably
cylindrical throughout. A slot is formed through the tail of the bolt, or for a
distance therein on each side, and the plain cylindrical end of a screw or equivalent
mechanisin enters therein. When the said screw or equivalent mechanism is drawn
back clear of the slot the bolt may be reversed by being simply turned a half revo-
lution, and the said screw or equivalent mechanism being again advanced (this time
into the opposite side of the slot) the bolt is retained in its reversed position. To
prevent any side strain on the screw or equivalent mechanism when the lock or
latch is in ordinary use, the spring or other mechanism bearing against the back of
the bolt (when such is the construction of the mechanism) is formed to gear into a
V or similar shaped recess at the back of the bolt, so that the bolt is kept from
turning in ordinary use, but may be turned when the screw or equivalent mechanism
is withdrawn by sufficient force (a comparatively small amount) being used to cause
the spring or other mechanism to move backwards out of the recess as the bolt is
turned. The said spring or other mechanism returns into the recess as the bolt is
turned a half revolution.
Having thus stated the nature of my said Invention, I will proceed more par-
ticularly to describe the manner of performing the same with reference to the
accompanying Drawings.
"
•

page_text: Figure 1 is a front elevation of a lock with my reversible latch bolt applied. In
this view the cap is removed, and the mechanism not required to illustrate my
Invention is omitted.
Figure 2 is a section on line x, x, of Figure 1. A is the reversible bolt ; B, the
crank; and C, the back follower. a is a forked end of the crank B, and fits into
each side of the cylindrical recessed part 6 of the bolt A. The end c of the back
follower C is shewn V shaped to fit into a corresponding recess at the back end of
the bolt A. D is a screw having a plain cylindrical part d within the slot F of the
bolt A. The head G of the bolt A is cylindrical, and a part H is cut out of the cap
and plate of the lock to allow clearance for the endway movement of the head G.
E is a plain stop to keep the tail of the bolt in gear with the crank B.
It will now readily be seen that in ordinary working the pressure of the part c
within the V'd recess, will prevent the bolt A from turning, and that the screw D
will effectually prevent the bolt being reversed while the lock is in place. When
it is desired to reverse the lock (which is of course always before the lock is fixed
in place), the plain part of the screw D is withdrawn clear of the slot in the bolt A,
and the bolt is then turned half a revolution without being moved in any other
direction, and the plain part of the screw is then returned into the slot F. The
head of the bolt is of course slanted in the ordinary way.
It is necessary that the recessed part b and the head G of the bolt A be cylin-
drical; but the remaining parts of the bolt A may be of any convenient section,
providing that such section is sufficiently small to turn clear of any obstacles. It is
preferred, however, to make the whole of the bolt A cylindrical, as thus the greatest
strength can be secured without interfering with the bolt being turned. The screw
D may of course be screwed in from the side of the lock case instead of from the
bottom, if preferred, in which case it may, if desired, pass through the lock from
side to side, having the head at one side and being screwed into the case at the
other.
Figures 3 and 4 are detached views illustrating a spring lever, which I prefer to
use in place of the screw D, the said views being respectively a sido elevation and
a plan. Jis the lever, having its fulcrum at K. L is a spring connected to the
lever J, and bearing against the rim m of the lock case. e is a stud on one end of
the lever J. The said stud e is pressed by means of the spring L into a hole
through the rim m; f is a projecting piece on the lever J, and projects in its normal
position into the slot F' of the bolt A'. When it is desired to reverse the bolt the
stud e is pushed up with any suitable instrument, and the projecting part is thus
withdrawn from the slot, and the bolt may then be reversed, when upon removing
the pressure from the end of the stud e the projecting part fis again forced by the
spring L into the slot F' and the stud e is forced back into the hole through the
rim m.
Figure 5 represents a front elevation of a lever lock with the cap removed, and
illustrates a further modification of my Invention.
This modification is the saine
as illustrated by Figures 1 and 2, except in so far as relates to the mechanism for
gearing into the slot in the bolt A".
In place of the screw D or lever J, as before described, I use in this case a lever
M, having its fulcrum at g. The said lever M is shewn detached by the side eleva-
tion, Figure 6. The vertical arm of the lever M is geared into a recoss h in the
tail of the lock bolt. The lock bolt is shewn in its mid-position. The arm i of the
lever M is in the position shewn (clear of the slot F" of the bolt A"), when the
lock bolt is in its mid-position, but projects into the slot F" when the lock bolt is
in its backward position, and thus when the lock bolt is unlocked the arm i is
always within the slot F, and prevents the bolt A" from being turned. When tho
lock bolt is held in its mid-position, as shewn on the Drawing, the bolt A" may be
easily reversed. The arm k projects into the front end of the slot Fll when the
lock bolt is locked, and thus locks the latch bolt A" by preventing the said bolt A"
from being drawn back.

page_text: The application of one or other modification of this Invention to other mortise
locks and to rim locks, and to mortise and rim latches will be sufficiently obvious
to a person skilled in the manufacture of such article, without need for special
illustration.
Having now particularly described the nature of my said Invention, and the
manner of performing the same, I declare that I do not limit myself to the exact
details as described and shewn, as such may be varied without departing from the
nature of my Invention; but what I claim as my Invention, and desire to secure by
Letters Patent is,―
1st. The reversible latch bolt having the cylindrical head and cylindrical recessed
part, substantially as and for the purpose herein described, and illustrated by the
Drawings.
2nd. The combination of the screw and slot with the cylindrical (or partly cylin-
drical, as described) latch bolt, substantially as and for the purpose herein described,
and illustrated by the Drawings.
3rd. The combination of the spring lever illustrated by Figures 3 and 4 with the
slot and cylindrical (or partly cylindrical, as described) latch bolt, substantially as
and for the purpose herein described, and illustrated by the Drawings.
4th. The combination of the lever M, in so far as relates to the vertical arm and
the arm i, with the cylindrical (or partly cylindrical, as described) latch bolt,
substantially as and for the purpose herein described, and illustrated by the
Drawings, namely, to form a stop to prevent the latch bolt from being turned when
the lock bolt is unlocked, the said stop being movable by means of the key.
5th. The V'd part, on the back follower or corresponding mechanism, gearing
into the V'd recess at the back of the latch bolt, substantially as and for the pur-
pose herein described, and illustrated by the Drawings.
In witness whereof, I, the said John Green, have hereunto set my hand and
seal, this Fifth day of September, in the year of our Lord One thousand
eight hundred and seventy-eight.
Witness,
STEPHEN WATKINS,
Assoc. Inst. C.E.,
Patent Office,
Wolverhampton.
JOHN GREEN. (L.S.)