Improvements in or relating to Air-ships or Vessels.
Year: 1899

page_text: Date of Application, 2nd Dec., 1899-Accepted, 6th Jan., 1900
Improvements in or relating to Air-ships or Vessels.
A communication from ERNST RUDOLF KROCKER, Merchant, of Teplitz,
Bohemia.
I, ALFRED JULIUS BOULT, of 111, Hatton Garden, in the County of London,
Chartered Patent Agent, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and as-
certained in and by the following statement:-
The present invention relates to air ships or vessels and particularly to means
of propulsion of such vessels. A ship or marine-propeller, even in a modified.
form and greatly enlarged form, will never be found suitable to act as a pro-
pelling agent for aerostatic purposes, since air is an elastic, compressible body
and is infinitely more mobile than water, and therefore is not sufficiently re-
sistant to the action of the blades of the propeller, and a great part of the power
employed is consumed in useless movement of the air, in the formation of air
whirls and like useless effects. A drawback of great importance is the effect
of centrifugal force. Instead of steadily working through the air and driving
back the air, the propeller forces great quantities of air laterally, uselessly com-
pressing the air round the vessel, while rarifying the medium,-otherwise
already too unsteady and unresisting-on which the propeller blades are in-
tended to act.
The object of the present invention is to increase the useful effect of the pro-
peller by placing it in a casing or cylinder open at both ends and with its axis
parallel to the direction the vessel is intended to travel, whereby the air, instead
of escaping laterally, is forced to move in a line parallel to the line of movement
of the aerostat. Owing to the arrangement of the cylinder surrounding the
propeller screw or blades it is possible to replace the ordinary form of marine-
screw-propeller by a kind of archimedean screw similar to a screw conveyor,
in which the blades extend close up to the inner surface of the cylinder the latter
thus co-operating with the former in such a manner as to fully utilize the pro-
pelling effect.
The invention can also be carried out in a modified construction, in which the
cylinder enclosing the propelling screw passes through the buoyant part, filled
with gas, of the acrostat, i.e., through the body of the apparatus instead of below
or at the sides.
The central driving effect, obtained by this arrangement will be found of
great advantage especially in connection with ellipsoidal or similarly shaped
balloons, as it is most suitable for keeping the desired direction of movement,
and because projections from and additions to the outer surface or contour of
the vessel should be limited, as far as possible, to the car carrying the motor.
In such an arrangement the fore part of the cylinder passing through the buoy-
ant part or halloon may be conically enlarged outwardly, whereby the air, drawn
in by the action of the propeller becomes compressed on entering the reduced
space of the cylinder, thus rendering more effective the work of the screw.
construction.
In the accompanying drawing the invention is represented in several forms of
anatomenation

page_text: In the form of construction represented in Figures 1 and 2, which will be
described first, the propeller screws are arranged outside the buoyant part of the
balloon.
From the ellipsoidal_shaped balloon a is suspended the customary car bin
which is placed the motor c. The aerostat is provided with three screw propellers,
actuated from the motor shaft d by means of band, cord or chain gearing. One
cylinder e is immovably suspended underneath the care and is provided at f f
with bearings for the screw shaft g. The screw resembles, as regards shape,
the well known form of conveyor screw. The screw may be considered. as being
generated by a rectangular metal sheet bent round its longitudinal central line.
The edges of the blades or wings are so formed that the screw h fits in the
cylinder e as closely as possible without touching it. The propellers provided
at the sides of the vessel are in every respect similar to the one described above.
The transmission bands or chains pass upwards over guide rollers k. This form
of construction is intended to serve as an example only of an aerial vessel accord-
ing to the present invention, the arrangement of which may vary to any extent
as regards number and the relative position in which the propellers may con-
veniently be fixed.
In the second form of construction the cylinder 7 (Figures 4 and 5) lies in the
axis and extends through the whole length of the buoyant part a of the aerostat
which, here also, is ellipsoidal in shape. In the fore part of the cylinder is
arranged the screw o carried on a shaft n turning in bearings m. The screw is
worked, in this case also, by a motor b placed in the car c, by means of a band
or other transmission device p which passes from the motor shaft to a pulley on
the propeller shaft through a tube 7 provided for that purpose in the lower part
of the vessel. The end r of the cylinder in front of the screw is conically en-
larged outwardly, the outward edge of this part forming with the surface of
the body a meeting it a kind of annular bow which cuts through the air. The
air entering this funnel-shaped space r is compressed on passing into the
narrower cylinder, and in this condition is attacked by the screw o and driven
backwards through the cylinder 7. In the case of exceptionally long cylinders
it will, perhaps, be found expedient to provide at the other end of the cylinder
a second propeller s as indicated in dotted lines in Figure 4.
The screws h (Figure 1) and o (Figure 4) are revolubly arranged in the fixed
cylinders in the two forms of construction described above; in another modifi-
.cation the screws are rigidly connected with the cylinders and both revolve.
In this case a perfectly close connection between the two can easily be obtained
and the wings or blades of the screw may also be made thinner and lighter since
they are strengthened through being connected at their outer edges with the
cylinder.
This modification can be easily effected where the screws are placed outside
the buoyant vessel. As shown in Figure 3 on the shaft g revolvably arranged
in bearings f, are fixed the screw blades and on them the cylinder or casing t.
In the case where the screw o is surrounded by the buoyant part a as shown
in Figure 6, the part of the fixed cylinder passing through the aerostat, where the
screw is located is enlarged and the screw with the cylinder connected to
it is concentrically and revolubly arranged within this enlarged space.
widened mouth of the cylinder is intended to act as a continuation of the
widened part of the cylinder 7.
The
Steering devices are not represented in the accompanying drawings since the
problem of steering an aerostat is contained in, and solved with, the problem of
propelling an aerostat in a required direction.
Having now particularly described and ascertained the nature of the said in-
vention, as communicated to me by my foreign correspondent, and in what manner
the same is to be performed, I declare that what I claim is:-
1. A propeller for air-ships comprising a conveyor screw revolubly mounted
in, or with, a cylinder open at both ends.

page_text: 2. A propeller for air-ships comprising a conveyor screw arranged in a cylinder
open at both ends and passing through the buoyant part of the air-ship.
3. A propeller for air-ships comprising a conveyor screw arranged in an open-
ended cylinder, the end of the cylinder in front of the screw being conically en-
larged outwardly.
4. A propeller for air-ships comprising a tubular conduit extending through
the length of the air-ship, a conveyor screw mounted or rotatable therein, said
screw being surrounded by a cylindrical casing, substantially as described.
5. An air-ship comprising a buoyant vessel provided with one or more conveyor
serews arranged outside or within the buoyant vessel and rotatable in a tubular
conduit or conduits substantially as described.
6. The complete means for propelling air-ships substantially as described or
illustrated in Figures 1 and 2, or Figures 4 and 5 of the accompanying drawings.
Dated this 2nd day of December 1890
BOULT, WADE & KILBURN,
Agents for the Applicant.
BOULT, WADE & KILBURN,
Agents for the Applicant.