Improvements in Floating Apparatus for Raising or Lowering Railway Trains, Ships, or other Heavy Bodies.
Year: 1891

page_text: Date of Application, 23rd Jan., 1891-Accepted, 12th Sept., 1891
COMPLETE SPECIFICATION.
Improvements in Floating Apparatus for Raising or Lowering Railway
Trains, Ships, or other Heavy Bodies.
I, ADOLF PRUSMANN, of 55, Hoher Wall, Dortmund, in the Empire of Germany,
Architect, 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 floating apparatus for raising or lowering railway trains,
ships or other heavy bodies; its object being to compensate for the gradually-
increasing tendency to rise which such an apparatus possesses the lower it is caused
to sink.
A platform mounted on air-chambers floating in water or other liquid contained
in reservoirs and used for the reception of the railway train, ship or other heavy
body to be raised or lowered is depressed or caused to sink into the liquid in the
reservoirs by certain weights, one of which is heavy enough to impart the requisite
velocity of movement Lo, besides overcoming the frictional resistance of, the
apparatus, while the other serves to overcome the buoyancy; the weight for over-
coming the buoyancy being incomparably greater than the weight for imparting
the desired velocity and for overcoming the slight friction incidental to the move-
ment of the apparatus through the water or other liquid.
In apparatus constructed according to my invention, part of the water or other
liquid in which the air-chambers float is used to overcome the buoyancy, so that
the weight hitherto employed for overcoming the buoyancy may be wholly or partially
dispensed with.
This result is obtained by the employment in the floating air-chambers of com-.
partments A, Figs. and 2, filled with air and furnished with pipes, which serve
to afford communication between the air-chambers and the fluid in the reservoirs.
The pipes should always be beneath the surface of the liquid. As the
air-chambers sink in the liquid, water enters the compartments by way of the
pipes; the air contained in the said compartments being consequently compressed.
The amount of water which enters the compartments A is in proportion to the
extent to which the apparatus is depressed.
Instead of two or more compartments A being employed in one air-chamber, only
one such compartment may be used.
It is well known that the volume of a gas is inversely in proportion to the
pressure to which it is subjected. Consequently if, when the compartments A. are
filled with air and the outer ends of the pipes are just beneath the surface of the
liquid in the reservoirs, the pressure of the air in each compartment be represented
by P, then, when the floating air-chambers have been fully depressed, such
pressure is increased and may be represented by P. If H be the height of the
volume of air when the pressure is P¹ and H* the height when the pressure
is P', then H.-H. When Frepresents the area of the compartments A, the
volume of water or other fluid which has entered through the pipes is represented
by F (H-
-
p1
P2
=
-
H) F (H-H*).
If, therefore, the tendency to rise on depres-
sion (assumed to be known) which would exist if no water were admitted into the
apparatus be represented by a weight M, then the weight of the volume of
water F (HH) should be equal to M. The proper size for each compart-
ment A can thus be readily ascertained.
「
P₁

page_text: The tendency of the apparatus to rise after being depressed, which tendency
varies at different depths of immersion, is counteracted by making the compart-
ments A of such dimensions as to always contain a body of water of appropriate
weight. These compartments should be located as high as possible, in order that
the air therein may be subjected to the greatest possible variation in pressure; a
more perfect action of the apparatus being thus obtained.
The interior of the air-chamber, Figs. 1 and 2, might be used to receive the
volume of water previously described as being received in the separate compart-
ments A, were it not that, in consequence of the large capacity of the air-chamber,
too great a quantity of water would enter. But this effect may be counteracted
and the difficulty overcome by the employment of air-spaces a, Figs. 3, 4 and 5,
situated in the interior of the air-chamber and serving to decrease the space therein
available for containing water. The air-spaces a may (to accord with the varying
amounts of pressure) be of different dimensions in different parts, as shewn.
Additional air-spaces
are provided at their upper and lower ends. The upper
additional air-spaces do not enter the fluid in the reservoirs until toward the
termination of the downward movement; they then serve to suddenly produce a
tendency to rise and bring the apparatus quickly to a state of rest. The lower
ones, toward the termination of the upward movement, begin to come out of the
fluid in the reservoirs; the tendency to rise being thereby suddenly diminished
and the apparatus quickly brought to a state of rest.
The platform may be connected with the air-chamber at the upper ends of the
air-spaces a.
If means, such as pipes furnished with stop-cocks, &c., be provided for allowing
air to escape from, or for forcing air into, the compartments or chambers in com-
munication with the water or liquid in which the apparatus floats, the buoyancy of
the apparatus may be altered at will to suit special circumstances.
Having now particularly described and ascertained the nature of this inven
tion and in what manner the same is to be performed, I claim :-
1. In floating apparatus for raising or lowering railway trains, ships or other
heavy bodies, utilising part of the water or other liquid contained in réservoirs in
which air-chambers float for the purpose of varying the buoyancy of the apparatus,
and of imparting to it a tendency to remain stationary in any position, such volume
of water or other liquid entering the apparatus during the descent of the latter and
serving to gradually compress a body of confined air, the reaction of which forces
the said volume of water or other liquid out again into the reservoirs during the
ascent of the apparatus, substantially as herein described.
2. In floating apparatus for raising or lowering railway trains, ships or other
heavy bodies, the employment of means substantially as herein described with
reference to Figs. 1 and 2 for regulating the descent and ascent of the apparatus ;
such means comprising air-compartments A attached to the closed air-chambers and
communicating by means of pipes r with the water or other liquid in which the
apparatus floats.
3. In floating apparatus for raising or lowering railway trains, ships or other
heavy bodies, the employment of an air-chamber containing closed air-spaces,
substantially as herein described with special reference to Figs. 3 to 6, for regulating
the descent and ascent of the apparatus; the air in the air-chamber being com-
pressed by the water admitted during the descending movement and reacting on
that water during the ascending movement.
4. In floating apparatus of the kind herein described for raising or lowering
railway trains, ships or other heavy bodies, allowing air to escape from or forcing
air into the compartments or chambers in communication with the water or liquid in
which the apparatus floats, so that the buoyancy may at will be altered according
to the load which at any one time is being carried on the platform.
5. The employment, in floating apparatus of the kind herein described, of

page_text: additional air-spaces, such as b, placed at the upper and lower ends of the apparatus
for the purpose of quickly bringing the apparatus to a state of rest at the termina-
tion of the upward or of the downward movement, substantially as set forth.
Dated this 23rd day of January 1891.
G. G. M. HARDINGHAM,
191, Fleet Street, London, E.C., Agent for the Applicant.