IMPROVED APPARATUS FOR AUXILIARY PROPULSION
Year: 1882

page_text: LETTERS PATENT to William Todd Lithgow, of the firm of Russell and
Company, Shipbuilders Port Glasgow in the County of Renfrew North
Dritain for an invention of "IMPROVED APPARATUS FOR AUXILIARY PROPULSION
LETTERS PATENT to William Todd Lithgow, of the firm of Russell and
Company, Shipbuilders Port Glasgow in the County of Renfrew North
Britain
invention of "IMPROVED APPARATUS FOR AUXILIARY PROPULSION
OF SHIPS OR VESSELS.
"
PROVISIONAL SPECIFICATION left by the said William Todd Lithgow
at the Office of the Commissioners of Patents on the 14th March 1882.
WILLIAM TODD LITHGOW, of the firm of Russell and Company, Shipbuilders,
" IMPROVED APPARATUS
Port Glasgow, in the County of Renfrew, North Britain,
FOR AUXILIARY PROPULSION OF SHIPS OR VESSELS,"
This Invention relates to improved means and appliances to be used for the
temporary propulsion of sailing ships or vessels which have become unmanageable by
being becalmed or disabled, or as an auxiliary means of navigating sailing vessels
in light winds, and which may also be applied for propelling steam ships whose
propellers may have been broken or become inoperative
The Invention consists essentially in fitting a propeller or propellers on swing
frames or brackets at each side of the ship in such a manner that they can be
shipped or unshipped and lowered into the water for temporary use, and in driving
these propellers by means of rope, chain, or other gearing from the steam winch or
winches, or other motive-power engine carried on the ship's deck.
In carrying out the Invention the auxiliary propellers are fitted in a framing carried
on a swinging centre on each side of the ship, this framing or bracket consisting of
strong rods or bars jointed at the vessel's side above the water line, and supported
by struts or stay rods which may be jointed or fitted in slides below the water
line. The outer end of this framing is fork-like or open, so that the propeller may
be fitted to revolve on a shaft carried in bearings in the extreme end of the
framing: A grooved pulley is fitted on this shaft, and a rope is carried over this
pulley and over a guide pulley at the ship's gunwale or side to a grooved pulley fitted
on the crank shaft or other shaft of the ship's winch.

page_text: When the auxiliary propelling power is not required, the propeller framings are
swung up to a vertical position on their centres or joints by hauling in the driving
rope or otherwise. The struts or stays, which are jointed to the main rods of the
frame, also hang vertically, and there is no obstruction to the vessel lying alongside
a wharf, while the propellers may be taken out and stowed away. But when the
auxiliary propelling power is required the propeller framing on each side is
lowered until the outer end with the propeller is immersed, and by means of the
rope or other gearing, the winch or other engine is made to drive the propellers.
The propelling power thus obtained will not in general be great, but will suffice for
carrying the vessel into the wind when becalmed, or for aiding the power of the
sails if the vessel is partly dismasted or otherwise disabled.
In a modified arrangement, the framings carrying the propellers, are fitted into
slide guides formed on the plates of the vessel's sides, so that the entire framing
may be lifted out or lowered to immerse the propellers. In this case an
arrangement of rack and pinion or screw would be provided for raising and lowering
the propeller framing.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William Todd Lithgow in the Great Seal Patent Office on the
13th September 1882.
WILLIAM TODD LITHGOW of the firm of Russell and Company, Shipbuilders,
Port Glasgow, in the County of Renfrew, North-Britain "IMPROVED APPARATUS
FOR AUXILIARY PROPULSION OF SHIPS OR VESSELS."
My said Invention relates to improved means and appliances to be used for the
temporary propulsion of sailing ships or vessels which have become unmanageable
by being becalmed or disabled, or as an auxiliary means of navigating sailing
vessels in light winds, and which may also be applied for propelling steam ships
whose propellers may have been broken, or have become inoperative.
My Invention consists essentially in fitting a propeller or propellers on swing
frames or on brackets at each side of the ship, in such a manner that they can be
shipped or unshipped and lowered into the water for temporary use, and in driving
these propellers by means of rope, chain, or other gearing from the steam winch, or
other motive-power engine carried on the ship's deck.
In carrying out the Invention, according to one modification, the auxiliary
propellers are fitted in a framing carried on a swinging centre on each side of the
ship, this framing or bracket consisting of strong rods or bars jointed at the vessel's
side above the water line, and supported by struts or stay rods, which may be
jointed or fitted in slides below the water line. The outer end of this framing is
fork-like or open, so that the propeller may be fitted to revolve on a shaft carried
in bearings in the extreme end of the framing. A grooved pulley is fitted on this

page_text: shaft, and a rope is carried over this pulley and over a guide pulley at the ship's
gunwale or side to a grooved pulley fitted on the crank shaft or other shaft of the
ship's winch.
When the auxiliary propelling power is not required, the propeller framings are
swung up to a vertical position on their centres or joints by hauling in the driving
rope or otherwise.
The struts or stays, which are jointed to the main rods of the frame, also hang
vertically, and there is no obstruction to the vessel lying alongside a wharf; while
the propellers may be taken out and stowed away. But, when the auxiliary
propelling power is required, the propeller framing on each side is lowered until
the outer end with the propeller is immersed, and by means of the rope or other
gearing, the winch or other engine is made to drive the propellers. The propelling
power thus obtained will not in general be great, but will suffice for carrying the
vessel into the wind when becalmed, or for aiding the power of the sails if the vessel
is partly dismasted, or otherwise disabled.
In a modified arrangement, the framings carrying the propellers are fitted into
slide guides formed on the plates of the vessel's sides, so that the entire framing
may be lifted out or lowered to immerse the propellers.
This modification of the Invention, which is preferred, is alone illustrated in the
accompanying Drawings, in which figure 1 is a longitudinal elevation of the
sliding frame carrying the propeller at one side of the ship, and figure 2 is a
transverse vertical section through the plates of the ship showing the carrying
frame and propeller in elevation. In these figures the propeller is shown as driven
by rope gearing, while in figures 3 and 4 which are views corresponding to
figures 1 and 2, but to a smaller scale, the driving of the propeller is effected by
pitch chain gearing.
Figures 5 and 6 are horizontal sections of the side plates of a vessel showing two
modifications of the slide guides for the carrying frams of the propeller. The
stem or bow of the vessel is indicated by the point of the arrow.
In each example
the propeller A is fixed on a short shaft B, which is fitted free to revolve in journal
bearings b at the outer end of a pair of strong iron or steel brackets C forming part
of the sliding frame C, C¹. This frame C, C', is formed with slide pieces or
feather C, projecting at each side beyond the brackets C, and fitting into guide
grooves & formed by guide pieces D rivetted to the ship's plates E on each side, or
in the case of wooden vessels, bolted to the ship's sides. The entire frame C, C²,
carrying the propeller is fitted to slide in the guides D, d, and can be raised or
lowered or altogether withdrawn from the guides D, d, by means of ropes or chains
and lifting tackle on board the vessel, connected to the upper cross bar C¹ of the
frame C, C. As a means of securing the frame C, C¹, in the requisite position
below the water level, and to prevent vibration of the frame, notches F are cut at
the inner side of the slides or guides D, into which jointed pawls or catches G fixed
to each side of the frame C, CT, are made to fit, and the framing C, C', is fixed in
position by securing the holding ropes or chains above. When withdrawing the
frame C, Č¹, from the slides D, d, it is slightly lowered, and the catches G are freed
by sliding on the angled sides of the notches F, or the catches G may be freed by
an arrangement of cords or lever devices worked from the deck. To prevent
flexure of the bracket frame C by the action of the propeller in rotating through
the water, strong wire or hempen guy ropes or chains H are connected to snugs c
formed on cross bars C³ near the outer end of the carrying brackets C, and carried
back towards the stern of the vessel where they may be secured through eyes
formed in brackets on the vessel's sides, or passed up to and through the scupper
holes and secured to cleats or other fastenings on deck.
The propellers may be of ordinary construction, but in the example shown in
figures 1 and 2, a grooved pulley I is cast or otherwise secured round the tips of
the propeller blades, which are made of malleable steel, and fitted into a cast boss.
Each propeller is driven by a rope or cord passed round this grooved pulley and
carried up either round guide pulleys to a driving pulley on the crank shaft or

page_text: other shafts of the ship's steam winch, or as is indicated in figures 3 and 4, carried
up to and round a driving pulley J on a shaft K overhanging the vessel's sides,
such shaft K being either connected direct to, or driven from the ship's steam winch
on deck.
In the modification shown in figures 3 and 4, there is fitted on the boss A' of
the propeller A, a pitch chain pulley I', over which is passed a chain driven by the
overhanging pulley J, on the shaft K above. The shaft K is supported over the
deck rail by means of a bearing bracket L, and is connected to the ship's winch.
In the arrangement shown in the Drawings, the propellers are most conveniently
fitted near amidships, or in line with the position on deck of the ship's steam
winch, but they may be fitted towards the stem or towards the stern of the vessel,
and be driven from the winch by means of a long shaft connected to the propeller
shaft B by a universal joint.
The propeller shaft may be fitted with a bevil wheel, and be driven by bevil
gearing from the winch shaft.
Having thus described my said Invention, and the manner of performing the
same, I have to state that I do not restrict myself to the precise details herein
described and delineated, but what I consider to be novel and original, and claim
as the Invention secured to me by the hereinbefore in part recited Letters
Patent is,―
First. As means for the temporary propulsion of sailing vessels, the arranging
and fitting of propellers on swinging or sliding frames at the vessel's sides, so that
the propellers may be driven by ropes, chains, or other gearing from the winch or
other engine on the vessel's deck substantially as herein set forth.
Second. The arrangement and combination of the sliding frame C, C', and
propeller A driven by ropes, chains or other gearing from the ship's winch,
such framing C, C, being fitted in guides D, d, on the vessel's sides, substantially
as and for the purpose herein described, in reference to the accompanying
Drawings.
Third. The combining of the movable frame C, C¹, carrying a propeller, with the
slides or guides D, d, substantially as and for the purpose herein set forth with
reference to the accompanying Drawings.
In witness whereof, I the said William Todd Lithgow have hereunto set my
hand and seal this Ninth day of September in the year of our Lord One
thousand eight hundred and eighty two.
Witness
WALLACE FAIRWEATHER C.E.
96 Buchanan Street
Glasgow
W. T. LITHGOW (L.S.)