An Improvement in Propellers for Navigable Vessels.
Year: 1891

page_text: Date of Application, 25th May, 1891
Complete Specification Left. 25th Feb., 1892-Accepted, 21st May, 1892
PROVISIONAL SPECIFICATION.
An Improvement in Propellers for Navigable Vessels.
GIOVANNI COSTANTE PARINI of 156 Dale Street Liverpool in the County
of Lancaster Restaurateur do hereby declare the nature of this invention to be as
follows:
The system of my invention is to leave free water from the blade discharging it
from the boss & throwing astern.
The blades may be constructed in any shape as long as there is a bend about t
from the boss & a slope at the root of the blade, so as to throw the water astern.
Therefore when the propeller is in motion there is no burden either going
down or coming up.
My invention is an improvement, when the blades are in motion they cut the
water just the same going down as coming up, and the slope mentioned in Specifica-
tion means to discharge the water from the stern instead of throwing it under the
hulk of the ship. So that it leaves the boss clear without lodging dead water.
Dated this 25th day of May 1891.
GIOVANNI COSTANTE PARINI.
COMPLETE SPECIFICATION.
An Improvement in Propellers for Navigable Vessels.
I, GIOVANNI COSTANTE PARINI, of 156, Dale Street, Liverpool, in the County
of Lancaster, Restaurateur, 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 :-
A propeller provided with the improvements hereafter described and according
to my invention allows the water to pass freely from the blades and be discharged
at the propeller boss directly astern.
In the carrying out of my invention, the propeller blades may be constructed of
any suitable shape but at about to the distance from the root to its extremity,
the blade is thrown back with a slope so as to allow for the easy passage of the
water away from the blade at the root and prevent it being taken round with the
blade.
By my invention when the propeller is in motion there is no burden or weight of
water on the blades or boss on the rise and fall of the propeller due to the pitching
of the vessel as the water is allowed to pass freely away at the root of the propeller
blades instead of being taken round with it.
Having thus described the object, nature, and effects of the invention, I will now
proceed to describe it with reference to the accompanying drawings which make a
part of this Specification and are marked with figures and letters of reference
corresponding with those used in the explanation.
In the drawings, Figure 1 is an end view of a propeller provided with the
improvement according to my invention (viewed from the back); and
Figure 2 is a side view of the same shewing the section and form of the blade
at the point where it joins the boss.
The lightly shaded section of the blade in Figure 2 is taken at the root of the
blade, viz., at X X Figure 1, whilst the darkly shaded section is taken at Y Y
Figure 1.
With reference to the drawings, a designates the boss of the propeller, and 6 the
blades thereof. c is the forward end of the propeller and d the after end. The

page_text: blades are of any known suitable shape, but according to my invention the part
of each blade enclosed by the part marked hhh is thrown back with a slope from
about the point e, to the point at which it joins the boss a, that is, this part has a
smaller pitch than the other part, but the effect of it is that it allows for the free
passage of the water away from the blades at the root thereof, namely, where the
blade joins the boss a.
The blades may be made separate from the boss and fitted on to the boss, if
desired.
Having now particularly described and ascertained the nature of this inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. A propeller for navigable vessels, constructed substantially as herein
described and shewn in the accompanying drawings, that is to say, a propeller in
which the blades are sloped back at and for some distance above the point where
they join the boss for the purpose set forth.
Dated this 24th day of February 1892
CHEESBROUGH & ROYSTON, Fels. Chart. Inst. P.A.,
15, Water Street, Liverpool, Applicant's Patent Agents.