Improvements in Air Propellers.
Year: 1893

page_text: Date of Application, 30th Oct., 1893
Complete Specification Left, 4th July, 1894-Accepted, 4th Aug., 1894
PROVISIONAL SPECIFICATION.
Improvements in Air Propellers.
We HUGH WILLIAM WADDLE of Llanmore Iron Works, Llanelly in the
County of Carmarthen, Engineer and ARTHUR JAMES BURN of Llanmore Iron
Works, Llanelly in the County of Carmarthen Engineer do hereby declare the
nature of this invention to be as follows:-
This invention has for its object to provide an air propeller in which the principle
of the "vena contracta " is applied to a screw air propeller. According to our
invention we combine with an ordinary screw propeller a circular casing in which it
is caused to rotate the said casing having a convergent inlet and a divergent outlet
for the air. The blades of the propeller may be so arranged that the air leaving
the tips or outer ends will strike against the surface of the divergent outlet and be
discharged therethrough with the additional force due to centrifugal action, as well
as that caused by the screw action of the rotating blades.
Dated this 30th day of October 1893.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W.C., Agents.
Improvements in Air Propellers.
We HUGH WILLIAM WADDLE of Llanmore Iron Works, Llanelly in the
County of Carmarthen, Engineer, and ARTHUR JAMES BURN of Llanmore Iron
Works, Llanelly in the County of Carmarthen, Engineer do hereby declare the
nature of our invention and in what manner the same is to be performed to
be particularly described and ascertained in and by the following statement :-
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Our invention has for its object to provide an air propeller in which the principle
of the
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vena contracta is applied to a screw air propeller. According to our
invention we combine with fan blades which may be arranged as an ordinary screw
propeller, a circular casing in which the said propeller is caused to rotate by any
suitable motor the said casing having a convergent inlet and a divergent outlet for the
air. The blades of the propeller may be so arranged that the air leaving the tips
or outer ends of the said blades will strike against the surface of the divergent
outlet and be discharged therethrough with, if desired, the additional force due
to centrifugal action, as well as that. caused by the screw action of the rotating
blades.
Figure 1 of the accompanying drawing is a front elevation and Figure 2 is a
vertical transverse section of an air propeller constructed or arranged according to
our invention, A. are the blades of a screw propeller mounted in bearings B carried
by the framings at each side of the casing C the interior of which casing is circular and
of such diameter that the ends or tips of the blades of the propeller rotate in proximity
thereto as shewn but of course without touching. The side a of the casing at which
the air enters converges inwards towards the blades of the propeller whilst the
opposite or exit side of the said casing diverges outward from the propeller blades
that is to say from the portion c of the interior of the case situated in or about the
plane of rotation of the tips of the blades of the propeller at which part the casing
is of such diameter as to-be just clear of the end of the blades as shewn.
D
When