Improvements in Propellers and Fluid Motor Wheels.
Year: 1893

page_text: Date of Application, 11th Nov., 1893-Accepted, 25th Aug., 1894
[Communicated from abroad by PAUL FREDERIC SCHMIDT, of Levallois-Peuret
(Seine), near Paris, France, Electrician.]
Improvements in Propellers and Fluid Motor Wheels.
I, RIDLEY JAMES URQUHART of 57, Barton Arcade, Manchester in the
County of Lancaster, Consulting Engineer and 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 ascertained in and by the following
statement :-
My invention relates to screw propellers for propelling ships, balloons and other
objects in water or air and for propelling water and air and for water and air
motors and consists in an improved construction or arrangement of propellers, the
object of my invention being to increase their efficiency or useful effect.
In the case of propellers as hitherto used, the power of the water put into motion
by the same is lost. The propeller imparts to the water a motion partly rotary and
partly backwards producing a flow diagonally along the blades outwards and the
energy contained in this water in motion is dispersed without being utilized.
I propose to utilize it by arranging a second propeller working round the ordinary
one with the same or a different number of blades inclined in the opposite direction
to that of the ordinary propeller and which is rotated in the opposite direction, so
that this propeller encounters, the current produced by the first propeller and
receives or absorbs the motive force contained therein. By working in this way
and utilizing the power otherwise lost a greater speed of propulsion is obtained
from the same motive power with a smaller number of revolutions of the propellers.
A third propeller may be arranged rotating round the second one in the same
direction with blades inclined as the first one. My invention thus consists in a
compound propeller or the combination with the ordinary propeller of one or several
opposite propellers surrounding each other and each rotating in the opposite
direction to the one surrounded by it.
In order that my invention may be more readily understood I have hereunto
appended a sheet of drawings on which
Fig. 1, A shows the inner and outer propeller combined in perspective.
Fig. 1 B the inner propeller separately.
Fig. 2 a method of driving them in opposite directions.
Fig. 3 a modifled arrangement of compound propeller.
Fig. 4 A B C D and E show the compound propeller as preferably arranged for
Ise as a propeller or fan for propelling or forcing air or water and as a wheel for
water and wind motors.
Fig. 5 shows the application of the propeller to a pump,
Fig. 6 its application to a ventilator or fan,
Fig. 7 its application to a water motor or turbine, and
Fig. 8 its application to a wind motor or wind turbine.
On Fig. 1B, the ordinary propeller is shewn which turns in the direction indicated
by the arrow f.
Fig. 1 A, shows as seen from the end, the same propeller combined with a second
uter propeller both of then being made with three blades. This outer propeller
turns in the direction indicated by the arrow f', that is to say in the contrary sense
o the inner propeller Fig. 1 B, and its blades m m, are inclined in the contrary
lirection to the blades H H, of the inner propeller. In consequence these
bladae m
1
1

page_text: Fig. 1 A and B, are intended to illustrate the principle or essential features of
my improved compound propeller, the constructive arrangement of which may be
carried out in various forms according to the power and purpose of the propeller
and the vessel or apparatus to which it is applied.
Figs. 2 and 3 show an arrangement suitable for the propulsion of boats. The
inner propeller with three blades a is of the ordinary form and is embraced by
the blades, of the outer propeller which are formed with openings for the inner
propeller to work through, the outer parts being mainly effective and the side parts
forming arms to sustain them. The two propellers are driven in opposite
directions as indicated by the arrows which may be done as shewn on Fig. 2.
The smaller propeller a is fixed on a shaft. c, driven by the engine and the outer
propeller bon a sleeve d, placed loose upon the shaft c. A bevil wheel e is fixed
on the shaft, and a bevil wheel 9 on the sleeve, both bevils gearing with a third
carrier wheel h, running on a stud or shaft i. Any other ordinarily used or known
suitable means for rotating the two propellers in opposite directions may be
adopted. The outer propeller in my arrangement would have about the same
diameter as the ordinary propellers at present in use for the same power and
the inner one would be considerably less in diameter, and the surface acting on
the water would preferably be made equal in the two propellers, so that the forces
balance each other.
The outer propeller blades may also be fixed to a ring K, as shewn on
Fig. 1A, the ring being supported by arms from a centre boss, or in any other
suitable way. The number of blades in the outer propeller may be the same as
in the inner or greater or less.
There may be a third propeller arranged surrounding the second one, with the
same direction of the blades and rotation as the first central propeller.
Propellers constructed on my improved plan may be used for propelling ships or
navigable balloons or applied for propelling water and air to centrifugal pumps and
fans or they may be used as wheels in wind and water motors.
For pumps and fans or motor wheels the propeller is preferably made with a
larger number of blades than three. Fig. 4 A shows an internal propeller with
five blades n, Fig. 4 B the corresponding outer propeller also with five blades m,
which for facility of manufacture are screwed to two bosses m¹ which embrace the
boss of the inner propeller; Fig. 4 C shows the compound propeller formed by the
two. Fig. 4D shows a compound propeller with ten blades to each of the component
propellers suitable for propelling air or for wind motors. The blades of the inner
and outer propellers are inclined in opposite directions as hereinbefore described.
It is not necessary that both propellers should have the same number of blades,
but they may have different numbers, as shewn by Fig. 4 E where the inner
propeller has four and the outer one five blades; and the outer and inner
propeller may be in some cases rotated at different speeds or numbers of revolutions
and have different angles of inclination to the axis, as may be found most effective
for the purpose for which they are used.
Figure 5 shows the application of the compound propeller to a pump. The internal
propeller is mounted upon a shaft a the lower end of which rests in a foot-step b
1orming a stuffing box; while the upper end has a bevil pinion e fixed on gearing
with the bevil wheel d. The external propeller m is fixed upon a hollow shaft e
guided at the upper end in a stuffing box f and carrying a bevil pinion g which
gears with the wheel d. The compound propeller is placed into a casing with a
small clearance between the tips of the blades and the wall of casing h. The
latter is formed or has fixed to it a lower elbow i for the suction, which carries the
footstep b, and an upper elbow j with the stuffing box f. On the shaft of the bevil
wheel d a pulley k is fixed and driven by a strap from a pulley on the line shaft, or the
shaft may be rotated directly or through gearing by a motor or by hand according
to the size and purpose of the pump. The inner propeller propels the water
partly in the axial direction and partly radially by centrifugal action, and this
radial flow is deflected and couverted into an axial flow by the outer propeller

page_text: blades encountering the same in the opposite direction, whence a great efficiency of
the pump results.
Figure 6 shows the application of the compound propeller to a ventilator, for
which purpose the propellers are preferably made with numerous blades. Motion
is imparted to the propellers, which are arranged upon an inner solid and an outer
hollow shaft as in the previous applications by means of a pulley k on the shaft
of bevil wheel d and the pinions c and g; the propeller being enclosed in a suitable
casing 1.
The
When arranged for a turbine, the propellers are placed within a cylindrical
case o provided with an inflow cone p and outflow cone p¹ to which other pipes may
be connected according to the position of the turbine or fall of water.
current in the direction of the arrow rotates the propellers m and n, mounted
respectively upon the hollow shaft e and internal shaft a in inverse directions,
which rotation is transmitted through the bevil pinions 9 and c and the bevil
wheel d to the vertical shaft g and thence in any suitable way.
Fig. 8 shows the use of the compound propeller as wheel for wind motors or
mills. The two propellers m and n will rotate in opposite directions under the
action of the wind and rotate the shaft g in the same manner as described with
reference to Figure 7. The hollow shaft e turns in a pedestal forming part of or
fixed to the frame s, which is fitted with a vane t to turn the propeller into the
direction of the wind, and supported on wheels n so that it can turn round the centre
of shaft 9.
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2°
The compound propeller or wheel gives a greater effect than a single propeller
or wheel of the same outside diameter and may be used for motors actuated by a
current of any kind of fluids, as well as for propelling fluids of any kind, and for
the propulsion of ships or other vessels in liquid or air.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is:
1. The arrangement of compound propeller consisting of two or more concentric
propellers of different diameters surrounding each other, the blades of each outer
propeller being inclined and rotated in the opposite direction to those of the inner
one surrounded by it, substantially as herein before described and illustrated by the
drawings.
2. In compound propellers arranged as hereinbefore described making the working
or acting areas of each propeller approximately equal.
3. The use of compound propellers arranged as hereinbefore described for the
propulsion of vessels or their equivalents in water and air, for propelling liquids or
air and for wheels in motors actuated by the flow of liquid or air.
Dated the 9th day of November 1893.
R. J. URQUHART,
57, Barton Arcade, Manchester, and 5, Clayton Square, Liverpool,
Consulting Engineer and Patent Agent.