Improvements in and relating to Looks.
Year: 1891

page_text: Date of Application (in United Kingdom), 27th Aug., 1891
Complete Specification Left, 27th Aug., 1891-Accepted, 31st Oct., 1891
COMPLETE SPECIFICATION.
Improvements in and relating to Looks.
I, WARREN HOWARD TAYLOR, a citizen of the United States of America,
residing at Stamford, in the County of Fairfield and State of Connecticut, one of
the United States of America, Gentleman, 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 relates to that class of locks using sliding or pin tumblers, which
tumblers lock a key-cylinder or roll-back to its surrounding case until the
tumblers are set by the insertion of the key, when the key-cylinder can be
revolved to operate the lock. Such a lock is illustrated by my United States
Patent, No. 208,863, dated October 8, 1878, and my present invention relates to
modifications of and improvements upon the construction there shown.
While the construction shown in my said Patent accomplishes the object of
supporting the key and preventing its tilting, and also is a considerable improve-
ment in the security of the lock against picking, it has been found that by the use
of a very thin picking-tool, formed of spring metal, the lock can be picked,
notwithstanding the sinuosity of the key-hole, because, although the section of the
key-hole is sinuous, the projections from its side walls do not extend beyond the
center or axis of the key-hole, and therefore do not effectually block the key-hole,
80 that picking-tools cannot operate the tumblers.
I am aware of the re-issue Patent of Schade, No. 9,787, which describes
projections from the opposite walls of a key-way, each extending past the center of
said key-way; but said projections are of different character from mine. Now to
increase the difficulty of picking, I have devised a key-cylinder having an improved
form of key-way, said key-way having projections which extend into it from both
sides past its axis or center, so that there is no space for the operation of a picking-
tool, however thin or flexible it may be. By referring to the sections of the key-
holes shown in the drawings it will be seen that if a picking-tool be inserted at the
bottom of the key-way it will not be possible, in consequence of the shape of said
key-way and of said projections, to raise the tool sufficiently to actuate the
tumblers. If a picking-tool is inserted at about the point to which the tumblers
drop or above the bottom of the key-hole, I have increased the difficulty of
picking by making the projections of a rounded or beveled contour on the side
which must be used for the support of the picking-tool, so that the tool will tend
to slide off from said projections as soon as pressure is applied to actuate the
tumblers, and when said tool has slid off, the shape of the projections on their other
sides is such as will tend to cause said tool to stick in the effort to restore it to the
position where it can actuate the tumblers. As shown in the drawings, the surface
of the projection which must form the support of a picking-tool is inclined so as
to cause the tool to slip and the other surface of adjacent projection presents an
obstruction to the raising of the tumbler by the tool. One surface of each projection
is inclined to the axis of the key-way at an angle more acute than the other surface
027

page_text: of said projection. It may he observed that in this construction it is not essential
or in many cases even desirable that a depression in the key should have a
corresponding rib or projection opposite thereto; nor is it essential that the key-
way should be of uniform width, or indeed of any particular section, the desirable
feature-being that there should be projections into the key-way extending past the
centre thereof, so as to form a barrier against the operation of a picking-tool and
to close the key-way, so that a picking-tool inserted at the bottom cannot raise the
tumblers sufficiently to set them. The shape of the projections, as above noted, is
also of importance, although not essential, except that it should be such as to
accomplish the object above stated. It is preferable that the key-way should be
continuous, but it is not essential to this invention, as it is obvious that substantially
the same results can be obtained by making a cylinder or plug in sections and
having one or more of said sections provided with the key-way of substantially
the shape above indicated'; 'or a cylinder might be made of one piece, and then
one or more disks inserted at one or more desirable points in its length, said disks
having key-ways of the shape above indicated. One construction, as just indicated,
is shown in my United States Patent, No. 234,213, dated November 9, 1880. It
is clear, also, that the particular means of manufacturing the cylinder and key-
way has no bearing on my invention, as it may be made in accordance with any of
my methods patented in the United States November 2, 1880, Nos. 233952,
233953 and 234089 and November 21, No. 267808 1882, or by forming it in two
pieces in the manner indicated in United States Patent of Henry R. Towne,
No. 234,630, dated November 16, 1880, or in any other manner, as may be most
convenient. In the construction shown in my Patent, No. 208,863, above referred
to, where the projections in the key-way and the grooves or indentations in the
key do not extend past their centers or axes, the bearing of the key upon the
tumbler is in the center of the tumbler, so that in inserting the key there is no
tendency to rotate the tumbler or to move it to one side. Hence, the tumbler may
be made cylindrical and have also a rounded or pointed bottom upon which the
key bears, and still when the key is inserted it will move at right angles to the
axis of the cylinder and be set for the operation of the lock; but with my
improved key and key-way it is clear that when the key is bitted into its
corrugations, inasmuch as the grooves or indentations and projections of the key
extend past its axis, the bearing of said key on the tumbler may be central or on
one side or the other of the axis of the tumbler, according to the depth of bitting.
With the ordinary cylindrical tumbler liaving a rounded or pointed bearing-surface
the result of this would be to push it to oue side and to cause a wedging action,
which would prevent the operation of the lock. I have, therefore, to overcome
this, invented' an improved form of tumbler which is cylindrical and provided with
a projection which engages with a corresponding groove in the tumbler-chamber,
so that the tumbler cannot rotate upon its axis, and the bottom bearing surface of
said tumbler is rounded or beveled on two sides of a central line only to form a
proper key-bearing surface, so that it will operate equally well on whatever point
of said bottom the key may bear. Of course the groove might be in the tumbler
and the projection on the tumbler-chamber, and other formal modifications might
be made. It is not material how the key is constructed or of what metal—that is,
whether' struck up, sawed, planed, or made in any other desirable manner.
Heretofore in constructing locks of this class it has been usual to make the
cylinders or roll-backs with a stop or head at the front portions thereof, which
construction by diminishing the diameter of the plug back of said head or stop
diminished the depth of the key-way. This was some disadvantage, because it is
desirable for the sake of combinations or permutations of the tumblers that this
key-way should be as deep as possible in a given diameter of escutcheon or
tumbler-case. In this lock I have devised an improved construction, which
consists in making the stop at the rear of the plug instead of at the forward end,
which enables me to make use of the greatest diameter of the plug to increase the
depth of the key-waj.
•12°
"

page_text: I am aware that in the United States Patent of C. C. Dickerman, No. 234,002,
dated November 2, 1880, the statement.is made that "the grooves or depressions of
the key admit of corresponding ribs or projections on opposite sides of the key-way,
each of which latter may project inward as far as or even beyond the central line
of the key-way," hut by reference to the drawings of that Patent it will be seen
that the class of locks referred to is not of the class to which my present improve-
ments relate. In the said Patent the disk or roll-back is entirely independent of
the tumblers in the sense that there is no connection between the tumblers and the
roll-back. In that lock the roll-back acts simply as a support to carry the key
when it is being rotated to operate the tumblers which are independently carried in
the lock-case. It is clear, therefore, that the only protection which the form of
key-hole or key-way in that Patont gives against picking is in making it slightly
more difficult to get at the tumblers, provided the picking-tool is inserted at the
back of the key-way-that is, that portion which when the roll-back is revolved is
farthest away from the tumlilers; but if a picking-tool sufficiently narrow. is
inserted, in that portion of the key-way in the said lock which, when the roll-back
is, revolved, will be nearest the tumblers, the projections of the key-way will not
seriously obstruct the operation of the picking-tool against the tumblers, because
such obstruction as is offered does not extend in any way to what may be termed
the "tumbler-space" that is, the space in which the tumblers themselves move
when being actuated by the key or picking-tool; but in my lock the key-way
into which the projections extend preferably runs the entire length of the
plug or roll-back, although the advantage of my invention may be measurably
secured. by making the plug in sectious, some of which are provided with
projections, and some not, as above set forth; but in any case in my lock the
cylinder or plug, itself carries those parts of the tumblers upon which the key
and the picking-tool must operate. The tumbler-chambers in which the tumblers
slide intersecting the key-way, and also intersecting the projections themselves,
the tumblers and tumbler-chambers may be protected by the projections and
in the.
the operation of a picking-tool therefore rendered extremely difficult.
Schade Patent above mentioned, the tumbler-chambers and tumblers do not
intersect the projections in the key-way, and the projections therefore do not
interpose the same difficulties to the use of a picking-tool as in my improved key-
way.
It will be seen, therefore, that my invention produces different results and in
a different manner than those produced by the Schade Patent or the Dickerman
Patent. In these Patents.there is no proper combination or relation between the
projections into the key way and the tumblers, whereas in my lock there may be
direct connection between the tumblers, tumbler-chambers, key-way, and projections
into it, the result being protection against picking, which is very secure, and much
greater than could be produced by the Dickerman or Schade device.
In the accompanying. drawings, illustrating my invention,
Figure 1 is a front end elevation of a pin-tumbler lock, showing one form of my
improved key-way.
Fig. 2 is a longitudinal diametrical section, showing the key in place.
Fig. 3 is a rear end elevation of the same.
Fig. 4 is a group of two detached tumblers, showing them in different positions.
Fig. 5 is a plan view of tumbler chambers in the casing, showing recesses to
correspond with the projections upon the tumblers; and
Fig. 6 is another group showing a formal modification, in. which there is a
projection from the wall of the tumbler-chamber and a corresponding recess in the
side of the tumbler.
Fig. 7 is a section similar to that shown in Fig. 2, except that the key is not
shown in place and the tumblers are shown as pressed down by their springs, 60 as
to intersect the projections in the key-way.
Fig. 8 is a front end view of the device shown in Fig. 7 with tumbler-chambers
dotted in..

page_text: Referring to the letters upon the drawings, A. indicates an escutcheon or tumbler-
case, such as ordinarily used in this class of locks. The shape of the tumbler-case
is not material, because this invention may be applied to locks of any other class,
Buch as cabinet-looks, padlocks, &c.
•
B indicates the hub or roll-back; C, the key-way therein; D, the key; E, the
pin-tumblers, and F their springs. The tumbler-chambers extend from the
escutcheon into the roll-back, as usual, and in general construction, and operation
my lock is the same as those of its class. The tumblers, it will be seen, have
projections G fitting into corresponding recesses or guideways H-in the casing. In
Fig. 6 the projection G is shown as upon the casing and the recess H in the
tumbler.
The key-way is provided with projections I from its opposite side walls, which
extend past its center, as illustrated, and which incline upon their upper surfaces
downwardly within the key-way-that is to say, on those surfaces which must be
used for the support of a picking-tool-for the purpose and with the advantage
above described. The lower ends of the tumblers with which the key-bits engage
in the operation of the lock are beveled into approximate V shape, as described, or
may be curved into approximate U shape, so that they are tapered suitably on
opposite sides of a horizontal line transverse to the length of the key-way.
Jindicates a stop at the rear of the plug instead of at the front end.
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. In a lock, the combination of a plug or key-cylinder provided with a key-way
into which projections extend from both sides past the center thereof, and tumbler-
chambers intersecting said key-way and said projections, substantially as described.
2. In a lock a key-cylinder or plug provided with a key-way into which pro-
jections extend from both sides past the center thereof, and tumbler-chambers
intersecting said' key-way and said projections, one surface of one of said projections
which must serve to support a picking-tool being inclined to the axis of the key-
way at an angle more acute than the other surface of said projection, substantially
as set forth.
3. In a lock, a plug or roll-back carrying a sliding tumbler and provided with a
key-way having projections extending from both sides past the center thereof, and
tumbler-recesses intersecting said projections, in combination with a key which has
key-bittings either central or on one side of its axis, said tumbler having a
continuous key-bearing surface wide enough to be operated by the bitting of the
key farthest from its axis, substantially as set forth.
4. In a lock, a cylindrical pin-tumbler with the end upon which the key bears
rounded or beveled only from opposite sides of a central line so as to form a broad
key-bearing surface, substantially as described.
5. In a lock the combination of a cylindrical pin tumbler rounded or beveled on
one end from the opposite sides of a central line, to provide a broad bearing surface
and provided with a projection or groove which engages with a corresponding
groove or projection in the case or chamber, so that when the key is inserted the
tumbler will revolve on its axis, substantially as described.
6. In a lock the combination of. a tumbler case or escutcheon and a key cylinder
or roll-back, with a stop against longitudinal motion in both directions at one only
thereof, so that said cylinder at the face of the escutcheon may be of its maximum
diameter to permit a deeper key-way, substantially as described.
Dated this 1st day of August 1891.
WARREN HOWARD TAYLOR.