An Improved Embrasure-joint for Gun Carriages or Mountings.
Year: 1891

page_text: Date of Application, 5th Jan., 1891
Complete Specification Left, 6th July, 1891-Accepted, 8th Aug., 1891
PROVISIONAL SPECIFICATION.
[Communicated from abroad by DIE ACTIEN GESELLSCHAFT GRUSONWERK, of
Magdeburg, Buchau, in the Empire of Germany.]
An Improved Embrasure-joint for Gun Carriages or Mountings.
I, HENRY HARRIS LAKE, of the firm of Haseltine, Lake & Co., Patent Agents,
45 Southampton Buildings in the County of Middlesex, do hereby declare the
nature of this invention to be as follows:-
This invention relates to an improved joint for tightly closing the space between
the gun and the embrasure in minimum-embrasure gun-carriages, which joint
operates like a stuffing-box, and entirely prevents the entrance through the
embrasure of the powder-gases which leave the gun at a very high pressure.
It is well known that, by the term "minimum embrasure," is understood an
embrasure in an armour-plate or shield, in the centre, or approximately in the centre
of which is situated the imaginary or virtual pivots or axes about which the gun is
turned for vertical pointing or elevation and training, or, in an armour-plated
revolving turret, for vertical pointing or elevation only. By this means, as
indicated by the term "minimum embrasure," the smallest practicable embrasure is
obtained, which bears somewhat tightly against the gun. Nevertheless these
arrangements, even when the long chase of the gun protrudes from the armour-
plate, have the defect that, on the firing of the gun, the powder-gases issuing at a
very high pressure from the muzzle, find access through the embrasure-joint into
the interior of the armour-plate or shield and cause considerable inconvenience to
the gunner.
Numerous arrangements of embrasure-joints have been devised with the object of
obviating this defect, but up to the present time, none of these arrangements has
fulfilled its purpose. The difficulty lies in the fact that simple metallic joints permit
the passage of the powder-gases notwithstanding the greatest accuracy in the
fitting of the parts, whilst hemp and asbestos joints, though they act well at first,
become useless after a few shots have been fired from the gun.
Now the present invention has for its object to automatically form an hermetic
joint during the firing, without interfering with the movableness of the gun.
For this purpose the gun is provided with a collar which is turned to a spherical
form. The centre of the sphere coincides with the point of inter-section of the
virtual pivots for the vertical pointing or elevation and the training of the gun.
The embrasure is bored out cylindrically at the inner side to form a kind of
stuffing-box in which a gland is fitted, this gland being secured and adjusted by
means of screws and nuts. The packing itself consists of a ring turned or bored out
spherically and made of soft metal, for instance, copper, which ring is fitted
accurately upon the said collar. To enable the said ring to be placed upon the said
collar, it is composed of two or more segments which may again be divided by a
plane joint at a right angle to the axis of the ring. The stuffing-box gland is
turned out conically at its forward end, and bears somewhat tightly against the
packing-ring, which is turned to a corresponding form.
If the gland were tightly screwed down, the packing-ring would, by means of
the conical part of the gland, be pressed so firmly against the spherical surface of the
collar, that the friction produced between these parts would not only render the
pointing difficult, but would also cause much wear of the packing-ring. The said
gland, however, is not intended to be tightly screwed down, but the parts are so
adjusted that the pressure which causes the hermetic closing of the embrasure, will
take place only upon the firing of the gun, and will be automatically effected by the
powder-gases, that is to say :-The stuffing-box gland is accurately fitted into the

page_text: .
bore of the embrasure (which may be provided with a leather packing) and is only
tightened to such an extent that the packing-ring usually acts as a bearing but not
as a packing. When, however, a shot is fired, the powder-gases under a high
pressure pass into the space between the embrasure-wall and the packing-ring, and
force the front part of the said ring directly against the spherical surface of the
collar, and also force the packing-ring into the hollow cone of the gland, thereby
effecting a further tightening between the said parts.
In the firing, the tightness of the joint at the forward end is somewhat diminished,
but the powder-gases penetrating at this point cannot pass through the embrasure,
and, therefore, they cannot enter the interior of the armour-plate or shield. After
the firing, as soon as the external pressure is diminished, the copper ring expands
again, that is to say, the pressure between the parts of the same and the, collar
is relaxed, and the gun can be easily pointed without impairing the quality of the
joint.
This is the characteristic feature and at the same time the chief advantage of the
invention.
The embrasure-joint may be adapted to a gun-carriage in which the gun is not
moved backward by the recoil, or to a revolving turret in which a horizontal
turning of the gun about a virtual pivot in the embrasure is not necessary, the
training being effected by the rotation of the entire turret. In the construction of
the embrasure-joint, no change is necessary when the training must be effected
by turning the gun, as the spherical joint permits motion in
direction.
any desired
When the gun-carriage is so arranged that the gun will move backward in the
recoil, the collar is held in any suitable manner in the embrasure and is provided
with a stuffing-box or with a leather or other packing-ring which is fitted upon the
long chase of the gun, the latter being turned cylindrical for this purpose, so
that the gun during the recoil and running out thereof, can slide in the said
collar.
Extensive trials have shown that this embrasure-joint fulfils its object in every
respect and is not injured by the firing of a great number of shots.
Dated this 5th day of January 1891.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.
COMPLETE SPECIFICATION.
An Improved Embrasure-joint for Gun Carriages or Mountings.
I, HENRY HARRIS LAKE, of the firm of Haseltine, Lake & Co., Patent Agents,
45 Southampton Buildings, in the County of Middlesex, 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 :-
This invention relates to an improved joint for tightly closing the space between
the gun and the edge of the embrasure in minimum-embrasure gun-carriages, which
joint operates like a stuffing-box and effectually prevents the entrance through
the embrasure, of the powder-gases which issue from the muzzle of the gun at a very
high pressure.
It is well known that, by the term "minimum embrasure" is understood an
embrasure in an armour-plate or shield, through the centre or approximately
through the centre of which embrasure extends the imaginary or virtual pivots or
axes about which the gun is turned for vertical pointing or elevation and for
horizontal pointing or training; or, in armour-plated revolving turrets, the virtual
pivot or axis about which the gun is turned for vertical pointing or elevation only.
By this means, as indicated by the term "minimum embrasure," the smallest
practicable embrasure is obtained, the edge of which somewhat closely surrounds
the gun.
This arrangement, however, even when the gun has a long chase which

page_text: protrudes through the armour-plate or shield, has the defect that, on the firing of the
gun, the powder-gases which issue at a very high pressure from the muzzle thereof,
find access through the embrasure-joint into the interior of the armour-plate or
shield and cause considerable inconvenience to the gunner.
Numerous arrangements of embrasure-joints have been devised with a view to
obviate this defect, but, up to the present time, so far I am aware, none of these
arrangements has fulfilled its purpose satisfactorily.
The difficulty lies in the fact that simple metallic joints permit the passage of the
powder-gases notwithstanding the greatest accuracy in the fitting of the parts,
whilst hemp and asbestos joints, though they act well at first, become useless after a
few shots have been fired from the gun.
Now the present invention has for its object to provide for the automatic
formation of an hermetic joint during the firing, without interfering with the
movableness of the gun.
In the accompanying drawing I have shown how the said invention may be
conveniently and advantageously carried into practice.
Figure 1 is a vertical central section through the embrasure of an armour-plate
or shield, a portion of the gun being shown in side elevation.
Figure 2 is a plan, partly in horizontal section, showing a slight modification of
the said invention, and
Figure 3 is a side elevation, partly in vertical central section, showing a gun-
mounting having the present improvements applied thereto, some of the parts being
removed.
The gun A is provided with a collar A' which is externally of spherical form,
the centre of the sphere coinciding with the point of intersection of the virtual
pivots or axes for the vertical pointing or elevation and for the training of
the gun.
The embrasure B' in the armour-plate or shield B, is bored out cylindrically at
the inner side to form a kind of stuffing-box, in which a gland C is fitted, this gland
being secured and adjusted by means of screws D and nuts D'. The packing
consists of a ring E made of soft metal, such, for instance, as copper, and turned or
bored out spherically; this ring is fitted accurately upon the collar A¹. To enable
the said ring to be placed upon the said collar, it is composed of two or more
segments, which may again be divided as indicated at a, Figure 2, the plane of
division being at a right angle to the axis of the ring. The stuffing-box-gland C
is turned or bored out conically at its forward end, and this end of the said gland
bears somewhat tightly against the packing-ring E, which is turned to a corre-
sponding form.
If the gland C were tightly screwed down, the packing-ring E would, by means
of the conical part of the gland C, be pressed so firmly against the spherical surface
of the collar A¹ that the friction produced between these parts would not only
render the pointing of the gun difficult, but would also cause much wear of the
packing-ring. The said gland, therefore, is not tightly screwed down, but the parts
are so adjusted that the pressure which causes the hermetic closing of the embrasure
will be applied only upon the firing of the gun, such pressure being automatically
applied by the powder-gases as follows, that is to say:-The stuffing-box-gland C
is accurately fitted into the bore of the embrasure (which may be provided at b with
leather or other suitable packing) and is only tightened to such an extent that the
packing-ring E usually acts as a bearing but not as a packing. When, however, a
shot is fired, the powder-gases under a high pressure pass at c into the space
between the embrasure-wall and the packing-ring E, and force the front part or
section of the said ring directly against the spherical surface of the collar A',
at the same time forcing the packing-ring E into the hollow cone of the
gland C; a further tightening of the joints between the parts E, A and C is thus
effected.
The operation of the two arrangements or modifications of my automatic gun-
embrasure joint represented in Figures 1 and 2, is, in this respect, the same.

page_text: In the firing of the gun, the tightness of the joint at c is somewhat diminished,
but the powder-gases penetrating at this point, cannot pass through the embrasure
either at d or at a or e, and, therefore, they cannot enter the interior of the armour-
plate or shield. After the firing and when the external pressure is diminished, the
pressure between the copper-ring E and the collar A' being relaxed, the gun can be
easily pointed without impairing the quality of the joint.
This is the characteristic feature and at the same time the chief advantage of the
present invention.
for a
The improved embrasure-joint is shown adapted to a gun-carriage in which the
gun is not moved backward by the recoil. Figure 3 shows a special arrangement
revolving turret in which the horizontal adjustment of the gun about a virtual
pivot or axis in the embrasure is not necessary, the training being effected by the
rotation of the entire turret. In the construction of the embrasure-joint, no change
is necessary when the training must be effected by turning the gun, relatively to the
turret, as the spherical joint permits angular motion of the gun in any desired
direction.
When the gun-carriage is so arranged that the gun will move backward in the
recoil, the collar A¹ is held in any suitable manner in the embrasure, and is
provided with a stuffing-box or with a leather or other packing-ring, which is fitted
upon the long chase of the gun, the latter being turned cylindrical for this
purpose, so that the gun, during the recoil and running out of thereof, can slide in
the said collar A¹.
Extensive trials have shown that this embrasure-joint fulfils its object in every
respect and is not injured by the firing of a great number of shots.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed as communicated to me by my
foreign correspondent, I declare that what I claim is :-
First. An automatic gun-embrasure joint, that is to say, an embrasure-joint which
is so constructed that the hermetic closing of the embrasure will be automatically
effected, on the firing of the gun, by the gas and air pressure produced outside the
embrasure.
Second. The improved embrasure-joint constructed substantially as described
with reference to the accompanying drawing and operating as, and for the purpose,
above specified.
1
ليم
0 T .
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.