Improvements in or relating to Screw Propellers.
Year: 1893

page_text: Date of Application, 2nd Nov., 1893
Complete Specification Left, 27th July, 1894-Accepted, 8th Sept., 1894
PROVISIONAL SPECIFICATION.
Improvements in or relating to Screw Propellers.
I, LEVI WILLIAMS LINDOP of 6, Dock Street, Ellesmere Port in the County
of Chester, Engineer, do hereby declare the nature of this invention to be as
follows:
This invention relates to screw propellers, and the object thereof is to arrange
for the pitch or angle of the blades being quickly and easily adjusted from the
engine room or other part of the vessel, whilst the engines are or are not in actual
motion. This enables me to obtain the exact pitch required, and, by a simple
movement of the blades, I can propel the vessel forward, reverse her motion so as
to propel her astern, stop the vessel altogether, or feather the blades so that they
are little or no obstruction to the vessel's progress through the water when she is
under canvas.
In carrying my invention into effect, the plan I prefer is to provide a hollow
boss or tail piece which is mounted on and secured to the end of the propeller
shaft. The shanks of the propellers are socketted or fitted into this tail piece so
that they can be rotated to any angle required. To each of these shanks inside
the hollow tail piece is firmly secured a crank, each crank being simultaneously
operated by a three armed lever secured to a horizontal rod or spindle which is
operated from the engine room or other suitable part of the vessel. This horizontal
rod is supplementary to the propeller shaft, which latter may be bored through
part of its length to receive the former. Both shafts rotate together but the
supplementary rod is capable of a horizontal sliding motion independently of the
propeller shaft, the latter being provided with a horizontal slot at a given point
which enables the spindle to be connected with an outside non-rotating sleeve.
This sleeve is coupled by a link to a hand lever.
The mode of action is as follows-
By pulling the hand lever, the rod together with the three-armed lever secured
thereon are moved horizontally, thereby operating simultaneously the cranks
secured to the blades and rotating the latter to the angle required. When the
lever is pulled over to one side, the blades are in position to propel the vessel
ahead. When pulled over to the other side, the blades are in position to propel
the vessel astern, and when in the middle position, the vessel stops, neither a forward
nor backward motion being produced by the blades. The end of the hollow tail
piece is by preference removable, so that the various parts can be examined and
repaired or renewed when required.
Dated this 1st day of November 1893.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Patent Agents for the Applicant.
0
COMPLETE SPECIFICATION.
Improvements in or relating to Screw Propellers.
I, LEVI WILLIAMS LINDOP of 6 Dock Street, Ellesmere Port, in the County
of Chester, Engineer, 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 screw propellers, and has for its object the alteration of

page_text: the pitch or angle of the blades at will, so that they can be quickly and easily
adjusted by a person in the engine room or other part of the vessel, according as
the apparatus is arranged and whilst the engines are or are not in actual motion.
By this means I can obtain the exact pitch required, and by the simple alteration
of the angle of the blades while in motion, I can propel the vessel forward or
backward or can place the propeller in such a way as to cause little obstruction to
the vessel's progress through the water when under canvas and in such position
that even if the engine were driven full speed, the propeller shall not in such case
increase or decrease the speed of the vessel.
The invention is best described by aid of the accompanying drawings, in which,
Figure 1 is a section of the propeller and boss ;
Figure 2, an elevation partly in section of my apparatus as arranged to work
from the tunnel;
Figure 3, a transverse view of the same;
Figure 4, a transverse view of Figure 1.
In these,
A, is a hollow boss or tail piece having a removable end B. CC are the blades,
each having a shank D with a good bearing in the boss A. They also have firmly
fixed to them a crank E. F is a spider-collar or lever rigidly fixed to the shaft G.
This collar or lever is slotted in each of the three arms to allow the crank pin' H to
slide in the said slot. The collar F is prevented from movement on the shaft G by
a small fixed collar I and a nut J. It is also preferably firmly keyed to this shaft.
Kis the driving shaft of the propeller firmly keyed into the boss A. It is formed
hollow so as to allow the shaft G to pass through its centre, and this shaft G is
lubricated by the oil cup L. M is a slot passing through the main shaft K.
A pin
or cotter N passes through this slot and through the shaft G. O is a box into
which the cotter N projects. The box, which is formed in two parts and united by
the bolts Q, rides on the shaft K and has a pin R, preferably on each side, upon
which is a link S. This link S is brought by suitable gearing or power conductors
to a hand lever T or other mechanism for giving a strong pull on the link S and
holding it in position.
It is obvious that the slots in the spider collar could be arranged spirally on the
periphery, the spider collar (in this case more correctly called a cam) could be
made to actuate the crank pins by a rotary instead of horizontal movement, but I
see no advantage in this variation.
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. In a feathering propeller the combination of the blades C, the cranks E
rigidly attached thereto and the collar lever or cam F engaging in the crank pins
of said cranks in such manner that as the collar lever or cam is moved all the crank
pins and the blades are simultaneously turned.
2. In combination with a central shaft G and a slot M and cotter N, a box O
sliding on the main shaft instead of a nut screwed thereon, as has been hitherto
used, and mechanism such as S and T for adjusting the position of this box
longitudinally on the shaft.
3. The apparatus for feathering screw propellers substantially as herein described
and illustrated.
Dated this ofth an T.L 1004
bd this 26th day
1004
WM. P. THOMPSON & Co.,
Of Liverpool, Manchester, l'irmingham, Nottingham and London,
Patent Agents.
WM. P. THOMPSON & Co.,
Of Liverpool, Manchester, l'irmingham, Nottingham and London,
Patent Agents.