IMPROVEMENTS IN GUN CARRIAGES
Year: 1884

page_text: I BENJAMIN BERKLEY HOTCHKISS of Paris in the Republic of France do hereby
declaro the nature of my said Invention for IMPROVEMENTS IN GUN CARRIAGES
and in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement :-
The object of my improvements in gun carrages is firstly to combat, diminish or
control the recoil of gun carriages due to the discharge of the gun, and secondly to
provide means of laying or pointing a gun horizontally, as well as vertically
without danger or inconvenience for the gunner, even during the discharge of
the gun,
•
In order that these improvements be clearly understood, as well as the means of
putting the same into practical operation, they are hereafter described in detail
conjointly with the seven Figures of the accompanying Drawing, as applied for
naval artillery and of which,
Fig. 1 is a lateral elevation of a cannon mounted on one of these improved
carriages.
Fig. 2 a plan of the same, the cannon being removed.
Fig. 3 an end elevation in section through the line y, y, Fig. 1, seen in the
direction of the arrow 1.
Fig. 4 a similar elevation in section through the line 5, 5, Fig. 1, seen in the
direction of the arrow 2.
Fig. 5 a partial plan in section through the line x, x, Fig. 3.
Fig. 6 a front elevation, and Fig. 7 a lateral sectional elevation of a modification
of part of the above-mentioned mechanism.
FIRST IMPROVEMENT. MECHANISM FOR COMBATING OR CONTROLLING THE RECOIL.
For this purpose, the cannon A is mounted on three superposed parts B, C & D,
the first of which B is the carriage properly speaking, which is composed of two
vertical walls of metal, such as wrought iron, united together at their front, by
tubular tyes 1, 1 and central bolts 2, 2, and at their rear by a bridge-piece 3, these
walls are provided above with bearings 4, 4 and caps 5, 5, for the trunnions of the
cannon A, below they are provided with four feet 7, 7, 7, 7; the second part C is
Duice Gd1

page_text: an open rectangular iron frame composed of two longitudinal girders united at
their forward ends by a cross-head 8, and at their rear by a crosshead g, and
internally they are provided with two longitudinal rails 10, 10; in the front cross
head 8 there is an axis on which this frame, carrying the carriage B, can turn
horizontally, whilst at the rear, it is provided with two rollers 12, 12 for the
displacement of its rear end on the foundation plate D, situated below, the rails
or flanges 10, 10 on the frame conjointly with the feet 7, 7, 7, 7, are instituted for
the longitudinal displacement of the carriago B; finally D the third of these parts
is a stationary or foundation plate provided at the front with a vertical bolt 13
round which the frame C with its carriage B are free to turn, and at its rear, with
two wings 14, 14 for the run of the rollers -12, 12.-Under these circumstances,
when the gun is fired, the carriage bearing with its shoes 7, 7, 7, 7 on the rails
10, 10' located within the frame C, would be driven back by the recoil and the only
resistance to this backward motion would consist in the friction of the shoes on the
rails; there is added to this resistance under these improvements an arrangement
of springs E E E Fig. 1 & 2 which unite the frame with the carriage and which
are distributed in pairs more or less numerous, one of each pair on either side of
the cannon; in reality, one single pair of such springs might answer the required
purpose, but it is considered preferable to subdivide the resistance due to one
single pair into several pairs of a lesser resistance; as it is represented in the
annexed Drawing, it is likewise considered more advantageous to set these springs
in an inclined position, because under these circumstances, they, not only oppose
the recoil by their compression, but they also compress the carriage on the frame
below, and in so doing augment the frictional resistance between these two parts;
were they set horizontally, it is true that their resistance to recoil would be greater;
but the frictional resistance would not in any way be augmented; in practice, it
has been ascertained that the combined action of these two kinds of resistance is á
very important element for combating as well as controlling recoil. These springs
Fig. 1 & 2 consist in a metallic box 15, the eyo 16 of which situated below is
passed over a stud 17 projecting from the side of the frame C, and in an internal
rod 18 terminated above by a hook 19 which is hooked on a stud 20, projecting
from the side of the carriage and below.by a washer or disk 21 ;.the spring itself 22
consisting in a strong steel wire wound spirally round the rod 18, being maintained
between the cap or cover of the box 15 and the disk 21; this mode of constructing
the said springs may be varied or replaced by any well known and appropriate
inode of construction. In the Fig. 6. &7, there is represented an arrangement of
caoutchouc springs which may likewise be utilized for the present Invention and
which consists in a case or box 15 closed below and provided above with a hook 19,
which hooks onto the stud 20 projecting from the carriage and in a head 23 formed
below with an eye 10 which is passed over a stud 17 projecting from the, frame
below, the spring itself 22 is passed on a central. rod or bolt 18 screwed below in
the head 23 and confined below by the bottom of the box 15.and above by tho
head 18* of the rod, under these circumstances the recoil of the gun is opposed by
the compression of the spring and this resistance augments. constantly proportion-
ately with the amount of the compression. Each pair of springs; arranged
externally on, the carriage, as above-described, may be replaced by a single spring
located internally on the central line of, the carriage, these springs may likewise bo
set to be acted on by extension instead of by compression, as above described, and
lastly it is to be understood that the above described metallic and caoutchouc
springs may be replaced by so called atmospheric springs, in which the same end is
attained by the compression of a certain amount of air by means of a piston in an
air tight cylinder. As a precautionary measure, spring buffers 24, preferably in
caoutchouc may be mounted on the rear crosshead 9 against which the carriage may
recoil and come in contact with: plates 25, forming part of the shoes 7, similar
buffers are mounted on the front cross-head S to limit the motion of the carriage in
the other direction.

page_text: I
7
SECOND IMPROVEMENT. MECHANISM FOR POINTING THE CANNON HORIZONTALLY
AND VERTICALLY.
רי:
For the purpose of pointing the cannon horizontally, I turn or rotate the frame C
with the carriage B and the gun round a vertical bolt 13 fixed in the foundation
plate D, and for this purpose, I fix at the rear of the said plate D a vertical
stand 26 on which I fix a rack 27 and on the rear cross-piece 9 of the frame C,
I cast or affix two arms 28, 28 in which I pass a shaft 29 provided at one extremity
with a hand wheel 30 and towards its center with a worm wheel 31 which gears
in the rack. When the hand wheel is rotated, it will be understood that since the
rack 27 is a fixture, the worm wheel will displace itself to the right or to the
left, according to the direction of the rotation imparted, carrying with it the frame
with the carriage and the cannon circularly around the bolt or axis 13 and when
such pointing, laying or adjustment has been effected, the different parts thus
displaced remain absolutely fixed or stationary and their position cannot be changed
otherwise than by rotating the worm 31, it is also evident that this pointing of
the cannon can be effected at all times, even during firing without danger or
inconvenience to the gunner.
For the purpose of pointing the gun vertically, I lower or I raise as may be
required the breech of the cannon A, the trunnions of which rotate in tho
bearings 4, 4 and these motions are produced by rotating, in one direction or in the
other the hand wheel 32; for this purpose, this hand wheol is fixed on the roar ond
of a shaft 33, which can be rotated in the bearing 34 which rises vertically from the
upper surface of the cross piece 9 of frame C, at its issue from this bearing the
shaft is made square and it passes in a square hole made in the worm 35 which is
supported to turn in the bridge piece 3 see Fig. 5, the said worm gears in a worm
wheel 36 fitted in a second aperture made in the center of the bridge piece 3, and
finally the vertical hub of the bridge is provided with a vertical round hole in
which is placed the elevating screw 37, which screws in the hole tapped in the
wheel 36 and the upper extremity of which is jointed to a lug provided on the
lower face of the breech. Since the worm 35 can slide freely on the square part
of the shaft 33 and since this latter as well as its bearing 34 are mounted on the
frame C and therefore are not affected by the recoil of carriage B, it follows that
even whilst the cannon is actually recoiling, the gunner may manipulate the hand-
wheel 32 in either direction, without risk or danger, consequently he is enabled to
follow and fire on a moving object, at all times. Either one of these arrangements
for pointing a cannon, may be employed separately.
The above described improvements may be adapted to field guns and other
military ordnance, by mounting wheels under the plate D.
Having now particularly described and ascertained the nature of my said
Invention, and in what manner the same is to be performed, I declare that what
I claim is :-
1. A gun carriage composed of three superposed parts B, C & D, together with
springs E uniting the carriage proper B with the frame C and which serve conjointly
with the friction of these two parts, to combat, diminish and control the recoil of
the cannon, as above described and illustrated in the seven Figures of the Drawing
annexed.
2. The construction of the frame C and the plate D with the rotating axis 13 in
front, and the rollers 12, 12 at the rear, conjointly with the worm 31, the shaft 29
and the hand wheel 30 mounted on the frame, and the rack 27 fixed on the
foundation plate D serving to point the gun horizontally, as above described and
illustrated in Fig. 1, 2, 3 & 4 of the Drawing annexed, and
3. The arrangement of the hand wheel 32, of its square ended shaft 33, of the
worm 35, of the worm-wheel 36 and of the elevating scrow 37, mounted respectively

page_text: in the bridge-piece 3 of the carriage B, and on the rear of the frame C serving to
point the gun vertically, as above described and illustrated in Fig. 1, 2 & 3 of the
Drawing annexed.