IMPROVEMENTS IN LOCKS AND KEYS
Year: 1883

page_text: PROVISIONAL SPECIFICATION left by Henry Harris Lake at the Office of
the Commissioners of Patents on the 16th January 1883. Communicated
to him from abroad by Joseph P. White of Savannah Georgia, United
States of America
"
HENRY HARRIS LAKE, of the firm of Haseltine, Lake & Co., Patent Agents,
Southampton Buildings, London, "IMPROVEMENTS IN LOCKS AND KEYS
[A communication to him from abroad by Joseph P. White of Savannah
Georgia, United States of America]
:
This invention relates to improvements in locks, which are to be applied to doors,
and to other objects which it is desirable to keep locked also to keys therefor; the
said invention is partly designed to provide a lock that shall be burglar proof, or
one that cannot be opened by drilling or cutting away the bolts which hold the
parts in their locked positions; and also to provide a novel construction and
combination of the parts of which the lock is composed, all as hereinafter set
forth.
In locks wherein a series of locking pins are employed very little protection is
afforded by reason of the fact that a burglar or other person seeking to gain admission
to the apartment can readily do so by drilling a small hole through the front plate
of the lock and then through the extension, thus cutting off all the pins, when the
locking cylinder can be turned and the door or other device opened, by turning the
locking cylinder.
The present invention is chiefly designed to overcome this objection; and to this
end, in constructing locks, I provide a plate of any desired dimensions, according
to the object to which it is to be applied. This plate I prefer to make of steel and
to harden it to such an extent as to render it impossible to perforate it with a drill.
Instead of making this plate of steel I sometimes make it of chilled cast iron, or of
any other material that will resist the action of a drill. As a further protection
against drilling away the locking pins, I place upon the outer end of the locking
cylinder, and between the said plate and a handle, a hardened collar the diameter

page_text: of which is equal to, or greater than, that of the cylinder. This collar is also made
impervious to a drill. There is therefore no part where a drill can be used for
cutting away the operating parts of the lock, and thus gaining access to the apart-
ment upon which it is placed.
I will now proceed to describe the features of novelty in the construction,
combinations, and arrangements of the parts of which this lock is composed. To
the inner face of the said plate there is secured, by soldering or rivetting, or by
casting thereon, a projection the central portion of which is cylindrical in form and
is bored out to receive the locking cylinder. Upon two sides of the said projection
are flanges through which a series of holes are drilled the number being such as to
admit of the insertion of the desired number of locking pins, say five, or more, or
less. These holes extend through both of the projections care being taken to have
those in one projection exactly in line with those in the other projection so that the
locking bolts may slide freely through them. The locking cylinder also has a series
of holes formed in it which correspond in number and size with those in the said
projections. The locking pins are preferably of hardened steel in order that they
may resist the action of the burglars drill, and are made in three sections, one of
the said sections being placed in the upper projection, one in the locking cylinder,
and the other in the lower projection. Above each of the upper sections there is
placed a spring, the said springs being held in position by a sliding plate. The
lower sections of these bolts are pointed at their lower ends and each one of them
is provided with a projection or pin. The combination and arrangement of the
last named parts is such that, when the locking cylinder is in this position, the
different sections will move freely up and down, but will not prevent the locking
cylinder from being turned by the handle into such a position as to cause an arm
to withdraw a main locking bolt which may be attached to the door of a safe or
other device and thus unlock it; or so as to throw the said locking bolt into its
locking position, a function which tho said arm performs in addition to that of
holding the lock in, or upon, the door.
The locking pins are brought into their unlocked position by the insertion of a
key provided with a series of holes of different diameters. To enable the operator
to insert the key, there is arranged in a block of metal which is secured to the
lower projection of the casing, a horizontally sliding pin the inner end of which
comes in contact with a bell crank lever. The effect of a push upon this pin is to
cause the lower arm of the said lever to come in contact with the lower end of a
vertical slide which works in a slot formed in the said block and raise it upwards,
whereby a horizontal arm formed upon its upper end, is brought into contact with
the projections on the lower sections of the locking bolts, and brings the latter into
such position that the key can be inserted, at which times, as above stated, tho
locking cylinder can be turned into such a position as to unlock the room or
receptacle to which the lock is attached. There is in the upper surface of the said
block a recess into which the key passes on being inserted, and the surface of this
block has in it a series of recesses, into which the points of the locking bolts drop,
when the key is removed; the effect of this arrangement is to allow the different
sections of the pins to drop down so that the lower ends of the sections will drop
into the holes in the lower projection and those in the upper projection into the
locking cylinder, and thus form two locking points. By reason of the different
lengths of the locking pins the arrangement of the holes in the key are of great
importance as if they are not of the proper arrangement and character the unlocking
cannot be effected owing to the fact that some of them will enter either the lower
projection or the locking cylinder, while the others are in a proper position for
unlocking. An important feature of the lock is that by changing the location of
the holes in the key and the pins in their places a variety of combinations can bo
formed and the unlocking of one lock with a key made for another lock can be
prevented. It is nearly, if not quite, impossible to pick the lock with any instru-
ment passed through the key-hole, as before it can be unlocked each one of the

page_text: locking pins has to be brought to an exact position and held there until all are
adjusted which cannot be done with any instrument or instruments except a key
fitted to the particular lock to which it is applied.
The extension of the locking cylinder is provided with a screw-thread for
attaching the said arm thereto, by which means it may be adjusted to doors of any
desired thickness.