IMPROVEMENTS IN ARMOUR PLATES
Year: 1886

page_text: Date of Application, 17th Mar., 1886.
Complete Left, 17th Dec., 1886.
Complete Accepted, 21st Jan., 1887
I, JOHN FRANCIS HALL of Norbury, Sheffield in the County of York Manager of
Steel Works do hereby declare the nature of my said invention for IMPROVEMENTS IN
ARMOUR PLATES to be as follows:-
My invention of improvements in the construction of Armour Plates has for its
object to improve the durability of such plates and to enable the hard face of the
plate to be made of good steel.
I carry out my invention as follows, I cast in metal chills preferably, or in any
other way small blocks of steel, of square, diamond hexagon, or other suitable form;
(for example they may be six inches square, by three inches thick) the runner being
left standing in the middle.
In casting these blocks, the metal is run round and upon four or any other number
of bolts standing upright round the said runner, and at a proper distance between the
runner and the edge of the block; the screwthread is enclosed in the casting and the
shank and head of the bolt are exposed.
These small blocks I prefer to cast in very hard and tough steel, as for instance a
Wolfram steel. **
.
•
Having cast a sufficient quantity of the blocks, I build them up on edge in a suitable
mould, so that their faces which were cast downwards will form a plain surface, and I
cast on to the backs of the blocks so built up a layer (for example seven inches thick)
of soft ductile steel or more correctly speaking, ingot iron.
This molten metal flows round and encloses all the runners and wrought iron bolts
projecting from the back of the small blocks of hard steel, and in cooling contracts
upon them, thus holding the whole mass in one rigid casting or block, and forming an
armour plate having a solid soft steel back and a face composed of a number of hard
steel blocks.
Instead of casting the soft steel back all in one, I can if desirable carry out the
principle of embedding a number of wrought iron bolts, and cast it in two layers,
thus the plate would consist of the hard blocks forming the face, the first layer of soft
metal held by the runners and bolts projecting from the backs of the blocks and the
second layer of soft metal held by the contraction of the metal round the bolts projecting
from the back of the first layer.
If therefore one of the hard blocks is broken up by the impact of a shot, it does not
follow that the crack will extend beyond the edge of the block so damaged.

page_text: I, JOHN FRANCIS HALL of Norbury Sheffield in the County of York Manager of
Steel Works 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 of improvements in the construction of Armour Plates, has for its
object to improve the durability of such plates, by reducing the liability to break up
from the impact of shot or shell.
The invention is carried into practice as follows, reference being made to the sheet
of drawings hereto annexed in which the same letters of reference indicate the same
parts in any of the figures in which they occur:
Fig. 1, represents a side view and plan of a cast. steel facing block.
Fig. 2, a modification of same.
Fig. 3, section of a finished plate. I cast in any suitable manner but preferably in
metal moulds or "chills" as they are technically called, blocks or sections of steel A, of a
suitable quality, either square as shown in Figs. 1 & 2, or of other shapes (as hexagon
for example) the said blocks when arranged together forming the face of the intended
Armour Plate.
I cast these blocks upon and enclosing a number of Bolts C, or double headed studs D),
which are supported in such a manner that a portion projects from the back of the
block as shown in Fig. 1.-Although I have shown the bolts with a screw thread, they
may be jagged or otherwise prepared so as to hold firmly in the hard and tough steel
of which I make the blocks.
I arrange the blocks so made edge to edge, so that their faces are level, and I then
cast against their backs a layer of soft ductile steel or "ingot iron "
thickness to form the back, marked B, in Fig. 3.
of any desired
This soft steel or ingot iron when poured in the mould flows round and encloses the
projecting bolts or studs, and upon cooling, contracts upon them, thus holding the
whole mass together as one block forming an Armour plate with a hard steel face
divided into separate blocks, upon a soft backing. Instead of the backing being made
in one piece, it may be cast in two or more layers, the various layers being connected
or secured together by being cast upon bolts, or studs projecting from the back of the-
previous layer in a manner similar to that before described.
Having now particularly described and ascertained the nature of my invention, and
in what manner the same is to be performed I declare that what I claim is :-
:-
-An Armour Plate, the face of which is composed of separate Cast Steel Blocks
secured to a back plate, or backing of softer metal by means of single or double headed
bolts or studs, cast into the back of the front blocks and afterwards attached to the
back plate by casting the molten metal of which the back plate is composed upon them,
substantially as described and illustrated.
2-Armour Plates consisting of separate Cast Steel facing blocks such as A, a backing
of softer material such as B, connected by bolts C, or double studs D, in the manner
substantially as described and illustrated.
RODT. F. DRURY,
Agent for the Applicant.