Improvements in Brakes for Gun-carriages.
Year: 1892

page_text: e of Application, 12th Aug., 1892-Accepted, 24th Sept., 1892
COMPLETE SPECIFICATION.
[Communicated from abroad by DIE ACTIEN GESELLSCHAFT GRUSONWORK,
of Magdeburg, Buckau, in the Empire of Germany, Manufacturers.]
Improvements in Brakes for Gun-carriages.
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:-
My invention relates to a brake for gun-carriages which is particularly adapted
for use upon wheeled gun-carriages. The object of my said invention is to provide
upon the gun carriage a simple and efficient brake which engages with the ground,
and offers to the recoil a resistance which is automatically proportioned so that it
may never cause the gun to jump.
According to the said invention the improved brake has a spur, arranged pre-
ferably on the trail of the gun-carriage so as to be forced into the ground and
increase the frictional resistance to the recoil. The resistance is kept constant
for any particular state of the ground by means of a special device hereinafter
fully explained.
In order that my invention may be clearly understood I will now proceed to
describe the same with reference to the accompanying drawings, in which
Figure 1 is a side elevation of the end of the trail of a gun to which an improved
brake according to my said invention is applied, and
Figures 2 and 3 are longitudinal central sections through the ends of other trails,
to which alternative forms of the said improved brake are applied.
Like letters indicate corresponding parts throughout the drawings.
With reference first to Figure 1, B is a spur adapted to turn upon a bolt C fixed
in the trail of the gun carriage, and provided with an arm b. F is a spring secured
to the trail with one of its ends arranged to bear upon the arm b. f is an
adjusting screw bearing upon the other end of the spring, and capable of being
adjusted in a suitable bearing in the trail to vary the compression of the spring
and the pressure on the arm b. When the gun is unlimbered the spur B is forced
into the ground by that part of the weight of gun and carriage which rests upon
the trail of the gun carriage. The said spur enters more or less deeply into the
ground according to the nature and condition of the same and is driven in still
further during the firing.
During the recoil the spur B cuts a furrow in the ground, the length of which
When
represents the minimum recoil reached under the conditions chosen.
succeeding rounds are fired this furrow is lengthened, as the shortness of the same
renders it superfluous to run the gun up to the original position for firing.
The device so far as it has been described would control the recoil upon ground
of a certain kind, if a fixed spur of suitable proportions were chosen. But if a
gun-carriage provided with such a fixed spur were brought upon firmer ground,
for example, jumping of the gun would soon occur, in the firing, as the resistance of
the spur to the recoil would exceed the admissible limit.
It is to permit of the regulation of the resistance offered by the spur, that, as
hereinbefore described it is pivoted upon the axis C; and the power of the spring F.
is such that in the recoil there will be a turning movement of the spur B upon
the axis C at the moment when the pressure of the wheels upon the ground
becomes approximately nil.
When the spur B turns, its depth of penetration decreases, and thus also the
resistance which it offers to the recoil.
Accordingly the said brake apparatus adjusts itself in each case automatically;"

page_text: as the brake spur turns exactly as far as the resistance of the ground demands.
The wheel brakes of the gun-carriage therefore become superfluous for preventing
recoil although they may of course be retained for other purposes.
The power of the spring F which is required for the purpose can be readily
calculated without difficulty and can moreover be regulated by the adjusting screw,
whilst the most favourable dimensions of the spur B can best be determined by
experiment. In lieu of the spring F weights could be arranged to bear upon the
spur B, but it is undesirable to increase the weight of the gun-carriage, by
employing weights in this manner. As another alternative, pressure may be
employed to bear upon the spur by any suitable means.
If it be desired to still further decrease the recoil at the expense of a slight
jumping of the gun carriage it is only necessary to increase the compression of the
spring sufficiently.
In the arrangements shown in Figures 2 and 3 the spur for reasons hereinafter
set forth need not be made of a length and width to render it suitable for use in
the softest ground. With reference now to Figure 2, K is a screw which bearsupon
a portion of the trail and passes through a block B' to which the spur is rotatably
secured. By employing the said screw to move the block the spur can be adjusted
so that it protrudes more or less from the trail of the gun-carriage. It is thus
adjusted when in use thereby enabling the resistance of the ground to act upon a
greater or smaller surface of the spur and its mean effective leverage to be varied.
In Figure 3.is shown an arrangement in which the spur is also automatically adjusted
vertically according to the nature or condition of the ground. In this modification
the pin C on which the spur turns is carried by an arm or frame N arranged to
turn about the second bolt L which is fixed in the trail of the gun-carriage. A
spring M.presses upon a part of the trail and upon the said arm or frame.'
According to the resistance of the ground and of the spring M the spur is forced.
more or less deeply into the same. O is a stop by which the downward movement
of the arm or frame N is limited..
To determine the dimensions of the spur let the assumption be made that it is
entirely sunk in loose ground in a vertical position, and that the gun is fired in
the lowest position of depression. The resistance offered by the spur to the recoil
of the gun must then be such that jumping of the gun round the trail of the gun-
carriage is just prevented or is confined to definite admissible limits. In general,
only the first case will have to be taken into consideration, that is to say the recoil
will be limited only to such an extent that jumping of the gun is just avoided.
If this condition is fulfilled the pressure of the wheels upon the ground will be
approximately nil at the moment of the firing, and the pressure of the trail of the
gun carriage upon the ground and therefore also the frictional resistance will reach
their admissible maximum.
As hereinbefore stated the object in the construction of such improved brakes is
to bring the resistance offered by the spur to the turning movement into proper
relation with the momentum of the force counteracting the jumping of the gun.
The designer will have to decide first how nearly it is desirable to approach the
attainable minimum of the recoil.
Having now particularly described and ascertained the nature of this 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 :-
1. A brake for a gun carriage in which a spur hinged to the carriage is adapted
to engage with the ground and is arranged to turn upon its hinge against elastic 5
resistance, for. the
purpose specified.
2. In a brake for a gun-carriage, the combination, with the aforesaid hinged
spur, of suitable means whereby the position of the hinge may be varied, sub-
stantially as, and for the purposes, specified.
3. In a brake for a gun carriage, the combination, with the aforesaid spur, of an .5
arm or frame pivoted to the carriage and automatically controlled by a spring or

page_text: springs, and having the said spur hinged thereto, substantially as, and for the
purposes, specified.
4. A brake for a gun carriage, substantially as hereinbefore described with
reference to Figure 1 or Figure 2 or Figure 3 of the accompanying drawings, for
the purpose specified.
Dated this 19th dox of dummot 1905
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.