Improvements in Burglar-proof Safes and Vaults.
Year: 1892

page_text: Date of Application, 19th July, 1892-Accepted, 17th June, 1893
COMPLETE SPECIFICATION.
Improvements in Burglar-proof Safes and Vaults.
1, WILLIAM CORLISS, of Narragansett Hotel, Dorrance Street, City of
Providence, in the County of Providence and State of Rhode Island, United
States of America, Engineer, do hereby declare the nature of my invention for
"IMPROVEMENTS IN BURGLAR-PROOF SAFES AND VAULTS," and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :—
I have discovered that a superior resistance to the attacks of burglars may be
obtained by making the safe of great thickness with the outer portion chilled cast-
iron, and the inner portion of soft iron traversed by bars of hardened steel. I attain
this condition and have the parts, each complete in itself, unaffected by its relation
to the other, by constructing each separately and applying them together cold.
To obtain access to the interior of such safe, a burglar must cut a large hole
through the exterior portion, because the inner portion cannot be drilled until the
temper of the steel has been drawn by heat. In the present state of the art there
is no means of applying sufficient beat except by a blow-pipe, and a small hole will
not admit of heating in the bottom of the hole by a blow-pipe.
The improvement may be applied to safes of various sizes made to serve either
as parts of a fixed vault or as portable safes. I will describe it as being carried
out in a portable safe.
I have set forth in the Specification of the British Patent to me dated July 25th,
1882, No. 3517, a construction of safe in which the exterior is approximately
spherical, and access to the interior is reached through a circular door, the entire
interior having liberty to revolve on a vertical shaft supported in bearings in the
top and bottom of the safe. And I have in said Patent also set forth a construction
having a main interior revolving frame with the door revolving on an axis carried
in such frame near one edge thereof.
This affords some advantages particularly for safes of large size. The present
invention applies to both styles of safe or to any other of a generally globular
form.
The interior portion of the shell is made in pieces and is put in as a separate
lining. One portion of the lining is a ring lying within the joint between the two
parts of the outer shell, and is screw-threaded on its exterior. It engages strongly
with each of the parts, and holds them together.
The outer portion gives strength and offers what I believe to be insurmountable
difficulties to the production by a burglar with the moderate resources at his
command, of the large hole necessary to admit of softening the steel bars in the interior
portion. The interior portion or lining offers difficulties to the penetration by a
drill or other tool which I believe to be insurmountable until the steel has been
softened. I esteem the safe absolutely invulnerable against any tools or powers
which burglars can employ.
The accompanying drawings form a part of this Specification and represent what
I consider the best means of carrying out the invention.
Figure 1 is a central vertical section partly in elevation, showing the invention
applied to a simple construction of safe, and
Fig. 2 is a section of a portion on the line -a; in Fig. 1.
Fig. 3 is a view corresponding to Fig. 1, but showing the invention applied to a
more elaborate form of safe.

page_text: Fig. 4 is a horizontal section of a portion on a larger scale.
Similar letters of reference indicate corresponding parts in all the figures where
they appear.
Referring to Figs. 1 and 2, A is the main shell of the safe, made in two rigid
pieces abutting squarely together, with a round bar of hardened steel let into the
joint, half in one part and half in the other, to make this part of the safe impenetrable.
The inner face of each part is screw-threaded near the edge, for a purpose which
will presently appear.
Bars m, of tough wrought iron, are cast in the shell A, in the manner set forth
in the first part of the said British Letters Patent No. 3517, of 1882.
I use the
proper iron and form the casting A, in chills, so that the entire exterior portion of
the casting A. has great hardness, which cannot be materially affected by heat.
The chilled iron encloses two series or layers of soft iron bars m, those in one layer
lying nearly or quite at right angles to the bars in the other layers.
I mount within these parts a lining Amade of soft cast iron, constructed in
separate sections, each having holes cored or otherwise produced in a direction
nearly parallel to the exterior of the safe, in which holes are enclosed bars P of
steel hardened to the highest possible degree. I have for convenience, applied the
term "bugs" to the hard steel bars thus conditioned.
The sectional lining is made with a concave dise at the back and the remainder
in vertical rings, formed independently each of the other, and independently of the
exterior of the shell. Each piece is finished with a joint adapted to match the
adjacent rings, and with an exterior face adapted to match against the inner face
of the outer shell A. The rings are applied together and brace each other like the
voussoirs of a masonry dome. This avoids the necessity for bolts or the like for
securing this burglar-proof lining in place. I have in my experiments cored the
holes in these pieces each in a cylindrical form, and have introduced the steel in
the form of cylindrical bars of nearly the same diameter, driving them forcibly into
place. There are two layers of these hard bugs, those in the inner layer lying
each just within the space between two of the bugs of the outer layer.
The largest ring A is screw-threaded on its exterior. It is screwed firmly
into the main body A and holds the entire lining in the main body fast. Then the
outer front part A is brought into engagement with the projecting edge of the
threaded lining, and is, by proper and efficient means, revolved until it is screwed
home. The parts are so fitted that when the outer parts A and A come tightly
together the outer edges of the lining ring just meet fairly and firmly against the
proper bearing in the interior of the front ring A'. The meeting joint of these
parts as well as the meeting joint of the parts A and A is defended by hardened
rings D let into the metal, half in each.
Figures 3 and 4 represent the main part of the invention applied to the form of
safe set forth in the third part of the said British Letters Patent dated July 25th,
1882, No. 3517, and which for brevity, 1 term a "planet" safe. The door revolves in
a frame carried in a larger frame revolved in the interior of the safe. This con-
struction is adapted for larger safes than that first shown. The main part of the
outer shell of chilled iron toughened by basket-work of wrought iron is in one
piece.
The ring C-around the door is soft iron studded with hard steel bars. It is made
in, three or more sections applied from the interior and strongly held in place by
collars or rings on its exterior engaging in grooves in the adjacent surface of the
shell A.
There are two large circular openings one in the top and one in the bottom,
closed by strongly screw-threaded parts B, which I designate the heads of the safe.
The main portion of each head is made of a sufficient thickness of cast-iron, the
exterior chilled and traversed by bars of soft iron, the interior soft and having two
layers of holes in which hardened steel bars are driven.
There are short transverse bars J of hardened steel set at two opposite positions

page_text: in the periphery of each head to still further defend against the possibility of
drilling.
These thick bars with the chilled cast-iron and tough soft bars in their interiors
correspond in appearance and in their general relations to the main body with
heads, set forth in my previous Patent, above referred to.
Modifications may be made without departing from the principle or sacrificing
the advantages of the invention. I have represented most of the lining rings as
having their inner faces presenting a straight outline in cross-section, and the holes
and the hardened steel bars P, are shown as straight. But these points may be
varied. I can, if preferred, make the inner faces of all the rings Aconcave, like
the smallest one, and some or all the holes and bars P may be correspondingly
curved. Or I can make the smallest one with a straight inner face and make the
holes and bars P, in that, the smallest lining piece, straight, making all the rest
curved.
The door may be defended by a separately formed lining of soft iron having bars
of hardened steel in holes cast therein. But the means for securing such lining to
the door are different. I propose in some cases to use Mushet steel or other self-
hardening metal for the bars P.
A safe constructed as herein described, instead of being portable, may form a
stationary part of a building above or below ground, and thus constitute what is
generally known as a vault.
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 burglar-proof safe a shell, the exterior face of which is of hard
metal and the interior portion of which is made separately as a lining and is
traversed by bars of hard metal, all combined and arranged substantially as herein
specified.
2. In a burglar-proof safe, an exterior shell of hard metal traversed by bars of
soft iron, and a separately formed lining of soft iron traversed by bars of hard
steel, applied together, substantially as herein specified.
3. In a safe a lining of separately formed pieces matched together like the
roussoirs of domes so as to be self-supporting, as herein specified:
4. In a burglar-proof safe, an exterior shell formed of separate pieces screw-
threaded interiorly near the line of junction, in combination with an exteriorly
screw-threaded connecting ring, substantially as set forth.
5. In a burglar-proof safe, an exterior shell formed of separate pieces screw-
threaded interiorly near the line of junction, in combination with a lining formed
of detached pieces matched together, and an exteriorly screw-threaded connecting
ring forming a part of the lining and abutting against the outermost of the other
lining pieces, substantially as set forth.
6. The burglar-proof safe described, having an exterior shell A A' in separate
pieces screw-threaded in their interior near the line of junction, and a lining
piece Aextending across the joint on the interior, separately formed of soft iron,
correspondingly screw-threaded, with hard steel bars enclosed therein, adapted to
serve the double function of a burglar-proof lining and a connection for the parts
of the outer shell, as herein specified.
1003
WILLIAM CORLISS.

page_text: this 13th day of June 1892, William Corliss, to me personally known, and declared
that he is the original inventor of the improvements set forth in the foregoing
specifications. Before me
GEO. O. STOCKWELL,
British Vice Consul.
W. Lloyd Wise,
46, Lincoln's Inn Fields, London, W.C., Applicant's Agent.