Year: 1885

page_text: I FREDERICK JAMES BIGGS, of Leadenhall Buildings, Gracechurch Street, in the
City of London, Merchant 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:-
My invention has reference to mortise locks which have tubular cases, that is to
say-cases whose section is of circular form, for the purpose of enabling the lock
to be readily inserted into a round hole, such as can be made by an ordinary auger.
Hitherto these tubular cases have been divided longitudinally into two parts or
halves, these halves being generally made of cast metal, and the lock mechanism
with its supporting bars or plates has been introduced into the case when the
halves have been apart. The external diameter of the tubular case is necessarily
limited by the thickness of the door into which it has to be inserted and as the
case itself, when made of cast metal, is somewhat thick the internal diameter bas
been so restricted that there has not been sufficient space vertically to provide for
the rise and fall of the tumblers or levers upon which the security of the lock
depends nor to allow of sufficient width in the locking plate and levers or tumblers
to permit of the cutting away or stamping out of the space in which the key
moves in the act of locking or unlocking; the wards of the key are thereby
rendered so diminutive as to make the locking weak, insecure or inoperative and
to create a difficulty in effecting differences or a variety of changes in the shape or
cutting of the tumblers or levers and locking plates with corresponding variations
in the wards of the keys, such security and differences being essential to render
the lock of public utility.
Now the chief object of my invention is to increase the available vertical space
for the lock mechanism and for this purpose I construct the lock with an inner
cylindrical frame having an opening from the upper side to the lower side in
which opening the lock plate or latch plate and the tumblers are fitted; the lock
plate or latch plate can thus be flush with both the upper and lower sides of the
frame while the tumblers have a similar vertical space in which to play; and
I enclose the cylindrical frame with its lock mechanisin in a case made of a drawn
tube in one piece; the walls or sides of this drawn tube are made as thin as
practicable-thinner than can be made by any other ordinary method-and the
cylindrical frame is inserted endwise into it through its open end and fits it snugly.
By this construction, practically the whole, vertical diameter of the mortise in the

page_text: door is rendered available for the lock mechanism the only perpendicular space lost
being the slight thickness of the tube at top and bottom. I also make the key-
hole or key holes horizontal instead of vertical as usual and place them at as low
a level as practicable, whereby the space in the locking plate and in the tumblers
or levers can be enlarged in accordance with the increased scope thus given to the 5
wards of the key in the locking or unlocking operations. The key-hole is made
double, that is to say; with the eye for the key stem in the centre so that a half
turn will be sufficient to enable the key to unlock or lock the bolt or latch and get
into position for withdrawal. I further provide means for adjusting the tubular
case to the inner cylindrical frame and preventing it turning round when once in 1
place whereby I ensure that the key hole or key holes that are cut in the tubular
case shall always be in position exactly over the key hole or holes of the lock. The
employment of a drawn tube for the outer case has the further advantage of giving
a more finished appearance to the lock than when tubular cases of cast metal are
employed.
the case a.
----
2
Figure 1 of the annexed drawings is a side clevation and Figure 2 a section on
the line 1
1 of a tubular lock case such as I use for the purpose of my
invention. Figure 3 is a side elevation and Figure 4 a rear elevation of a latch
lock with the tubular case applied thereto. Figure 5 is a similar view to Figure 3
but with the tubular case in section. Figure 6 is a section on the line 2
of Figure 5. Figure 7 is a plan view of the lock with the tubular case removed.
a is the tubular case made of a drawn tube closed at the rear end b and open at
the front end. In this tube or case is formed at one side or both sides, as may be
required, a key hole or key holes c at such point of the tube's length as will come
exactly over the corresponding hole or holes d of the lock when the lock is inserted
into the tube. e, e is the inner. frame containing the lock mechanism which may
be of any desired construction. The frame c is preferably made in two parts, one
of them being permanently fixed to the fore-plate f while the second is fixed to
the first by a screw 7. The two parts together form a cylinder which snugly fits
The cylinder e, e has however an opening extending through it from
top to bottom as clearly seen in Figures 6 and 7, and in this are the tumblers or
levers k, k and the latch plate or lock plate . The plate is flush with the top
and bottom of the frame e, e while the tumblers k, k have play for the full height
of the frame. The case a is not fixed in any way to the fore plate f. The frame e
is introduced into the case a through the open front end and when it has been
pushed home they are secured together by means of a screw 9 passed through a
countersunk hole in the rear end b of the case into a threaded hole in the inner
end h of the frame e. In order to ensure that the key hole or key holes o of the
tubular case may come exactly over the hole or holes d of the lock and that the
tube may not turn round upon the frame e there is a projection i on the end of
the frame which enters a hole or recess made for the purpose in the rear end b of
the case at. Other means for effecting this adjustment and preventing the turning
of the case may be substituted for the projection i and corresponding hole as will be
well understood; for instance instead of the single central screw g to secure the
case a to the frame e there may be a screw out of the centre or two screws at
opposite sides of the centre or a screw at the side of the tube. It is not essential
for the frame e, e to be cylindrical, but its periphery must fit the tube a at a
sufficient number of points to guide it into place and to act as a stay or internal
support to the tube. The key-holes c and d in the tube a and frame c respectively
are horizontal and double and placed low down in the lock for the purpose already
herein explained. I do not however confine myself to making the horizontal or
double but this is of great advantage where the circumference of the lock is very
small.
My invention is applicable to mortise locks of all descriptions whether latch
locks, such as that shown (and which may have either a spherical ended latch, as
represented, or a latch of other form), or "dead" locks or two bolt locks, that is to
say-locks which contain both a latch and a bolt,

page_text: Having now particularly described and ascertained the nature of my said
Invention, and in what manner the same is to be performed, I declare that what
I claim is
1. In a mortise lock, an inner frame carrying the lock mechanism and having an
opening in same extending from the upper side to the lower side, in combination
with an outer case formed of a drawn tube in one piece into which the said inner
frame fits substantially as herein before described.
2. In a mortise lock, having an inner frame carrying the lock mechanism and
an outer case formed of a drawn tube in one piece into which the said inner frame
fits I claim the horizontal double key holes in said frame and case substantially as
and for the purpose described.
3. In a mortise lock, the combination with an inner frame carrying the lock
mechanism and having an opening in same extending from the upper side to the
lower side, and with an outer case formed of a drawn tube in one piece into which
the said inner frame fits, of means substantially as described whereby the said
inner frame and outer case are secured together and rotation of the one relatively
to the other prevented.
4. The projection i at the rear end of the inner frame e, e in combination
with a hole or recess in the rear end of the outer case a as and for the purpose
described.