CERTAIN IMPROVEMENTS IN BREECH-LOADING ORDNANCE
Year: 1868

page_text: LETTERS PATENT to Alfred Krupp, of Essen, in the Kingdom of
Prussia, Cast Steel Manufacturer, for the Invention of "CERTAIN
IMPROVEMENTS IN BREECH-LOADING ORDNANCE."
Sealed the 23rd February 1869, and dated the 7th December 1868.
PROVISIONAL SPECIFICATION left by the said Alfred Krupp at the
Office of the Commissioners of Patents, with his Petition, on the
7th December 1868.
ALFRED KRUPP, of Essen, in the Kingdom of Prussia, Cast
Steel Manufacturer, do hereby declare the nature of the said Inven.
tion for "CERTAIN IMPROVEMENTS IN BREECH-LOADING ORDNANCE," to be as
follows:-
These improvements consist in certain mechanical arrangements for
more easily and effectually manipulating the wedge and for opening and
closing the breech, and also for effectually locking such wedge in its
position for firing, and at same time accurately determining that the

page_text: wedge is in its proper position in the gun; also for igniting the charge
in the gun by a vent through the centre of a wedge.
The means I use for manipulating the wedge and for locking the
same when in its position is a male screw working through a female
screw or long nuts. These screws are in a recess in the wedge, and the
neck of the first screw lies within the breech-piece plate against which
it rests by a collar. The end of this screw is formed with a square on
which a handle is placed for working it. The opposite end of the screw
forms a pin, and this part rests in the wedge. As the screw at one end
resis firmly against the breech-piece plate by means of the collar, and at
the other end les fly against the wedge by means of the pin, it
follows that the screw is only capable of a rotary motion on its axis, but
not of any independent motion in the direction of its axis. The female
screw or nut works upon the screw, and both are in the same recess in
the wedge. The length of this recess is greater than that of the female
screw, so that the female screw can move a little way backward and
forward. There is a projection upon the female screw to limit its rotary
motion by striking against the breech-piece plate at top and bottom.
The female screw has several rings on its outside, the first of which
towards the breech-piece plate is complete while the rest are partially
cut away. When the gun is closed these rings fit into recesses in the
gun and thus lock the wedge, but when the gun is open then these
portions of rings leave the recesses in the gun and allow free action of
the wedge. The manner in which these operations are effected is as
follows: Presuming the gun to be closed and it is desired to open it
and unlock the wedge, a handle is placed on the square end of the screw
and turned to the left as far as it will go. By this means the female
screw moves at first a little longitudinally and then turns with the male
screw until the projection strikes on top against the breech-piece. plate,
and at the same time the rings are withdrawn from their recesses in the
gun. The projection on the female screw prevents it turning any further
and forces it therefore more on the male screw towards the gun until
the first ring lies against the gun. This movement also tends to start
the wedge, which is then withdrawn by the removing screw. The closing
.of the gun is effected by reversing the above operations.
My method of igniting the charge is by means of a central vent
through the wedge in the direction of the axis of the bore. For this
purpose there is in the wedge a vent bush of steel or copper, or some

page_text: other metal or combination of metals. The double cock is attached
to the bush direct or to the wedge, behind which the friction wire or
percussion tube is placed when the gun is to be discharged.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Alfred Krupp in the Great Seal Patent Office
on the 7th May 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALFRED
KRUPP, of Essen, in the Kingdom of Prussia, Cast Steel Manufacturer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Seventh day of December, in the
year of our Lord Oue thousand cight hundred and sixty-eight, in the
thirty-second year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Alfred Krupp, Her special
licence that I, the said Alfred Krupp, my executors, administrators, and
assigns, or such others as I, the said Alfred Krupp, my executors,
administrators, and assigns, should at any time agree with, and no
others, from time to time and at all times thereafter during the term
therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "CERTAIN IMPROVE-
MENTS IN BREECH-LOADING ORDNANCE," upon the condition (amongst others)
that I, the said Alfred Krupp, my executors or administrators, by
an instrument in writing under my, or their, or one of their hands
and seals, should particularly describe and ascertain the nature of the
suid Invention, and in what manner the same was to be performed, and
cause the same to be filed in the Great Seal Patent Office within six
calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said Alfred Krupp, do hereby declare
the nature of the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement thereof, reference being had to the Drawings here-
unto annexed, that is to say:
These improvements consist in certain mechanical arrangements for

page_text: more easily and effectually manipulating the wedge used for opening and
closing the breech, and also for effectually locking such wedge in its
position for firing, and at same time accurately determining that the
wedge is in its proper position in the gun; also for igniting the charge
in the gun by a vent through the centre of the wedge.
In Sheets I. and II. of the Drawings hereunto annexed I have shown
so much of the breech end of a gun as is necessary to exemplify these
my improvements. Figures 1, 2, and 3 represent in each Sheet respec-
tively end view, plan in section, and side elevation of the breech end of
the gun fitted with my improvements. In Sheet I. the breech is shown
as closed when firing the gun, and Sheet II. the breech as open when
loading. Corresponding letters of reference indicate similar parts in
each of the Figures.
A, A, is the gun through the breech of which is cut a slot, the vertical
section of which shews a semicircular line at the back and nearly rectan-
gular line in front. The horizontal section shews a taper a, b, c, d, of
which the side a, b, is perpendicular to the axis of the bore, while the
side c, d, shews an inclination of 1° 55' to that axis. I do not, however,
confine myself to this angle, but have found it in practice to be the best
for the efficient working of the wedge. 9, 9, 9, are semicircular slots
cut in the metal of the breech for purposes afterwards explained. The
diameter of the powder chamber is increased and recessed as shown, in
order to receive the expanding ring B for the purpose of preventing the
escape of gas when the charge is exploded. The bore of the breech
behind the wedge slot is somewhat increased in order to receive the
loading box C, shewn in Figure 2, Sheet II. D is the wedge which is
of a cylindro-prismatic shape, and corresponds with the shape of the
slot a, b, c, d, in the breech. This wedge I prefer to make of steel. By
this form of wedge a perfect closing of the powder chamber is secured
when the wedge is firmly pressed into the slot. Guide bars are formed
on the top and bottom of the wedge fitting into corresponding recesses
or grooves cut in the top and bottom faces of the slot and parallel to the
back line c, d, of the slot. By means of these guide bars and grooves
the wedge is caused to work accurately to and fro in the slot, the back of
the wedge always sliding on the back surface of the slot and in close
contact, while the front surface of the wedge will from the same reason
gradually recede from the front surface a, b, of the slot as the wedge is
withdrawn when preparing to load the gun. The following is the means

page_text: by which I work the wedge to and fro in the slot when opening and
closing the breech :-E is a square-threaded screw kept in its place in a
groove on the top of the wedge D by means of the collars F and G, and
also by the half nut EI fixed to the breech by the screw h. The end of
the screw is formed with a square e on which can be fitted the handle I
when working the screw. P is a recess cut in the end of the wedge and
closed by the plate R, in this recess is placed the locking apparatus for
securing the wedge form lateral movement when the gun is discharged.
This apparatus consists of a screw K working in its nut L. The neck k
of the screw K is fitted and works in the plate R, being kept in its
position by a brace. The end of the screw K is formed into a square, on
which the same handle I can be fitted when locking or unlocking the
wedge. The opposite end of this screw is fitted into a recess in the
wedge but is free to turn therein. The screw K being thus fitted
between the plate R and the recess in the wedge is free only to turn
upon its axis. The nut L on the screw K is of less length than tho
recess, in order that it can move to and fro for a certain distance, equal
to about one-third of a circle, this movement being regulated by a catch
or stop upon the head of the nut. This catch, according to its position,
comes in contact with the top or bottom by the closing plate R. The
nut on its outside is cut with projecting threads, the first thread being a
complete circle, but the others are partially cut away, as shown in
Figure 2, Sheet II. When the breech is closed these threads, on the nut
enter into the slots g, 9, 9, in the breech and thus lock the wedge in its
position and prevent all lateral movement; but when the wedge is to be
withdrawn the nut is turned so as to liberate the threads from the
slots g, g, g, and then the plain part of the nut is in conjunction
with the slots. The escape of gas when the gun is fired is effectually
prevented by the ring B, which when the wedge is in its position for
firing the gun comes in close contact with the recessed plate M fitted
into the face of the wedge and slightly projecting therefrom. The ring B
also slightly projects beyond the face a, b, of the slot. The traverse of
the wedge is limited by means of a chain attached at one end to the
gun at m, and at the other to the wedge at n, Figure 1, Sheets I. and II.
5 The loading box C is introduced into the bore after the opening of the
breech, and is kept in its position by the handles o, o, fitting into the
hooks p, p, screwed into the gun, as shewn in Figure 2, Sheet II.
Presuming the breech to be closed as in Sheet I., and it is desired to
open it for loading the gun, the following are the means to be used:

page_text: The handle I is placed on the square end of the screw K and turned to
the left. By this operation the nut L moves slightly in the direction of
the axis of the gun, then turns with the screw K. until the catch comes
in contact with the plate R. The portion of threads on the nut L will
then be withdrawn from the slots g, g, g. As the catch a will not allow
a further rotation of the nut L it is forced to move along on the screw K
towards the gun until it comes in contact with the end of the recess P,
and thereby becomes fixed. By continuing the rotation of the screw K
the wedge will be slightly withdrawn. The handle I is then transferred
to the square end of the screw E, the turning of which to the left
withdraws the wedge to the limit allowed by the chain. The loading
box C is then introduced, and the gun can be charged in the ordinary
way. To close the breech the reverse action is followed; the loading
box is withdrawn and the screw E turned to the right, which brings the
wedge again within the breech until the brace of this screw touclies its
nut; the handle I is then placed on the screw K and turned to the
right until the outer end of the nut L touches the closing plate R; the
nut then turns with the screw K and the threads enter the slots g, g,
and the catch is in contact with the bottom of the plate R. This
rotary movement of the screw is continued, and the plane surfaces of the
threads on the nut L pressing on the corresponding surfaces of the
slots 9, 9, the wedge is forced into its exact position in the breech and
also locked.
For igniting the charge I make use of a steel or copper vent V passed
through the wedge, as shewn, so that when the breech is closed the
centre line of the vent corresponds with the axis of the bore, as shewn
in Figures 1 and 2, Sheet I.
In witness whereof, I, the said Alfred Krupp, have hereunto set
my hand and seal, this Fourth day of May, in the year of our
Lord One thousand eight hundred and sixty-ninc.