IMPROVEMENTS IN MACHINERY OR APPARATUS FOR ASSISTING IN PROPELLING VESSELS
Year: 1854

page_text: LETTERS PATENT to James Rae, of No. 1, Alpha Road, New Cross, in
the County of Kent, Civil Engineer, for the Invention of "IMPROVEMENTS
IN MACHINERY OR APPARATUS FOR ASSISTING IN PROPELLING VESSELS."
Sealed the 27th April 1855, and dated the 1st November 1854.
PROVISIONAL SPECIFICATION left by the said James Rae at the Office
of the Commissioners of Patents, with his Petition, on the 1st November
1854.
I, JAMES RAE, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN MACHINERY OR APPARATUS POR ASSISTING IN PROPELLING
VESSELS" to be as follows:-
I propose that the propeller should rest on external bearings, which are to
be so placed as to be at all times accessible without disturbing the propeller or
the shaft. One bearing is placed on a bracket formed on the stern post;
another external bearing rests upon a carriage suspended by means of metal
rods. The advantages of these proposed bearings over those usually adopted and
placed upon the rudder post are, first, that the propeller is not inconvenienced
by the vibration or strain which the rudder post is subjected to in a heavy sea;
but, on the contrary, being independently supported and kept up.to.its-bearings

page_text: with the greatest accuracy by supporting rods, which can be at all times regu-
lated with accuracy, as the wear of the bearings may require; secondly, that
when a vessel grounds, instead of the propeller being deranged by the probable
destruction of the rudder post, the independent bearings preserve it from
injury. To secure another advantage in this arrangement, it is proposed to
place metallic discs upon the propeller shaft, to act as journals, running in
metallic bearings. The journals in this plan being much larger in diameter
than the ordinary journals upon propeller shafts, afford a greater amount of
surface, and are consequently calculated to wear much longer.. The journals
are to be adjusted or removed at any time, or replaced with new ones, if re-
quired, without disturbing the propeller or shaft, besides preserving the shaft
in its original shape, and saving time and expence.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said James Rae in the Great Seal Patent Office on the
30th April 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
RAE, of No. 1, Alpha Road, New Cross, in the County of Kent, Civil
Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the First day of November, in the year of our Lord
One thousand eight hundred and fifty-four, in the eighteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said James. Rae, Her special licence that I, the said James, Rae,
my executors, administrators, and assigns, or such others as I,-the said
James. Rae, my executors, administrators, and assigns, should at any time
agree with, and no others, from time to time and at all times thereafter
during the term therein expressed, should and lawfully might make, use,
exercise, and vend, with the United Kingdom of Great Britain and Ireland,
the Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
MACHINERY OR APPARATUS FOR ASSISTING IN PROPELLING VESSELS," upon the con
dition (amongst others) that I, the said James Rae, by an instrument in writing
under my hand and seal, should particularly describe and ascertain the nature
of the said Invention, and in what manner the same was to be performed, and
cause the same to be filed in the Great Seal Patent Office within six calendar
months next and immediately. after, the date of the said Letters Patent..

page_text: NOW KNOW YE, that I, the said James Rae, do liereby declare the nature
of my said Invention, and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following state-
ment, reference being had to the three Sheets of illustrative Drawings here-
unto annexed, to the diagranis shewn thereon, and to the letters of reference
marked thereon, to denote similar parts where such parts appear or can be
seen respectively.
But before proceeding to describe the particulars of my Invention, it may
be as well to explain the causes which have led me to consider its adoption on
board screw ships, not only advisable, but decidedly necessary. It is well known
that the working of the shaft and screw causes great wear in the casing and
bearings, and that in a short time the great working weight causes the stern
tube or orifice in the stern of the vessel and next the screw to become enlarged
at its lower part or bearing surface. Directly this takes place the position of
the shaft is no longer truly horizontal, and the shocks to the screw in' working
are thus permitted to attain a gradually increasing power of loosening the shaft
in its socket supports or bearings, and finally occasions the necessity of taking
the ship into dry dock, where most extensive repairs and renewals of parts of
the apparatus are found to be necessary. The ship, of course, being detained
from service during the period occupied in effecting these repairs, renders the
loss to the owner from the above-stated cause very considerable; and if the
screw apparatus breaks down abroad, where there may be no docks to receive
the craft, then, as in the case of the Croesus, at Melbourne, some some short
time since, the delay caused very great loss, and the repairs being superficially
executed, it cannot be denied but the safety of ship and equipage was materially
endangered on the homeward voyage; possibly, on enquiry; the loss of this
vessel off Genoa with troops may be found to be in part owing to the causes
and imperfections above alluded.to.
+
The object of my Invention is to remedy the defects in the present system
of. screw apparatus, by introducing a simple and effectual means of supporting
the screw propeller in such manner that it shall at all times be maintained in
its proper horizontal position, and as the after end of the shaft will be entirely.
independant of the rudder post, so that any shock or damage 'sustained by the
rudder or rudder post (which too frequently occurs), will have no effect upon
the propeller shaft, screw, or bearings.
In the accompanying Drawings, Figure 1, Sheet 1, is a vertical longitudinal
section of part of the counter and stern of a vessel, with part of the shaft, the
screw, and bearings, shewn in the Diagram; Figure 2 is a sectional plan at A; A,
Figure 1. In Sheet 2,. Figure 1 shews a cross section, taken through A, A,

page_text: Figure 2, Sheet 1, and Figure 2 of the same Sheet is a side clevation, of part
of ship's counter and stern, shewing the supports, screw, and part of shaft; and
Figure 3 is a plan taken at B, B, Figure 2. In Sheet 3 a series of sections
are shewn, to illustrate the various parts of my Invention, and the mode of
fixing, attaching, or working the same; Figure 1 being an elevation of my after
bearing; Figure 2, a cross section of my after bearing; Figure 3, end view
in section of after bearing with cap; Figure 4, end view of after bearing
without cap; Figure 5, eud view of the stern post of ship fitted with my
bracket; Figure 6, front or forward view of stern post and bracket;
Figure 7, plan of bracket for supporting bearing; Figure 8, elevation of pro-
pellers, boss, or nave, and after bearing; Figure 9, cross section of my forward
bearing and Figures 10, 11, and 12, plans of forward bearing. It will be
seen that the forward bearing a rests upon a cast or wrought iron bracket c
(built with the vessel); or in case my apparatus is to be applied to a vessel
already built, this bracket may be made of gun metal, or other suitable metal.
The bracket c is fitted with an internal carriage, made of brass or other suitable
metal, this carriage being furnished with six (more or less may be used, but
I prefer the number, stated,) Muntz metal set screws, for the purpose of easing
the weight from the forward suspension rod d. The suspension rods d, e, (I
call & the forward rod, and e the.after rod,) may be made of any suitable metal,
copper, brass, iron, or other. The forward rod d is passed up through a hole
in the stern of the vessel made to receive it, and is suspended on plates of
wrought iron, or other suitable metal, set on edge and running across the
stern of the ship, united by angle irons, and is provided with a nut f, to enable
the propeller with its shaft and bearings to be lifted or screwed up, by aid of the
spanner g, when it is found that any wear has taken place. This being done,
and the shaft and adjuncts in their proper or original horizontal position, the
six set screws-are to be screwed down until the whole of the strain is taken off
the suspension rod d, and thrown upon the bracket c. The carriage h-is fitted
with a half bearing, which I make of brass or cast iron (chilled or otherwise).
This bearing is fitted so that it can be removed at any time, and replaced with
another when necessary without removing the propeller or shaft; but this will
-rarely be needful, as the bearing i is made of considerable thickness, and as
the shaft can be raised when the wear has taken-place-by_the_suspension
rods. The nuts f upon the said suspension rods can be tightened up by the
socket spanner g, worked off the ship's deck, or the shaft may be raised by
leverage applied in the cabin. The lining j, which is fitted upon the shaft
both for its preservation and as extra surface bearing, may be made of
wrought or cast iron (chilled or otherwise), and of any convenient or pro-

page_text: portionate thickness, and being turned to fit the bearing i, complétes it, that is.
to say, the bearing in and next the stern of the ship.
I will now proceed to describe my after bearing", which is entirely sus-
pended by my suspension rod e, and is constructed as to be altogether clear
or free of the rudder post. The after bearing sling or case 7 may be made
of any suitable metal, or wrought or cast iron, (chilled or otherwise,) or brass;
as may be desired, and is fitted with bearings, shewn at a, a, and b, l';
Sheet 1, made of similar metal, as aforesaid, the whole to be made portable to
allow of its being easily and promptly removed, and replaced with a new one
when necessary without disturbing the shaft or propeller. The extremity of
the shaft supported by this bearer is to be furnished with a casing or lining;
similar to that just previously described, and made of similar metal. The
after suspensión ród e is passed up through a hole in the ships stern made
for its reception, and supported in the same manner as directed in regard to
the forward suspension rod d; and the propeller and shaft is to be raised or
lifted in the same way when requisite. By the adoption of the various
apparatus herein-before described to ships using screw propellers I obtain
many advantages; amongst others, a greater amount of wearing surface is
obtained by lining or encasing the shaft of the propeller as described, such
casing or lining preserving the shaft in its original form, and consequently,
increasing its durability; again, in the insertion of the half bearing, so that it
can be removed easily and promptly without disturbing the propeller or shaft;
also suspension by rods of the carriage, so that it may be screwed up or raised
at pleasure when any "wear" is discovered to have taken place, and secured
in position by the tightening of the six metal set screws. By these arrange-
ments the engineer has always in charge the whole of the stern "gear" of the
ship, and can adjust it satisfactorily whether the ship be at sea or in port, a
manifest advantage, there being many localities where defects cannot be repaired
or made good for want of docks, as before mentioned. I would observe that the
outside bracket can be applied with great advantage to ships already built, and
will when applied avoid the necessity of having the bearing in the stern tube,
as is now generally the case, and which my previous remarks have shewn to be
inefficient and-dangerous. It may so happen that it will be found impracti-
cable to get the suspension rods through the stern of a ship; in such case the
said rods may be suspended by brackets fixed on, in, or to the dead wood of
the vessel's stern, or otherwise by cutting an aperture in the dead wood, so as
to pass the rod through, and to admit of a nut to carry the same; or by any
modified application that may be in such case found to answer, as by levers or
springs. This remark applies only to ships already constructed, as provision

page_text: may always be made in new ships for the insertion of the suspension rods,
which may, if desirable, be made to work in tubes, as protection or casing to
the rods, if found desirable.
Having now described the nature of my Invention, and the manner in which
the same is to be carried into practical effect, I desire it to be distinctly under-
stood, that I do not confine myself to the exact positions of the various parts
herein described, or to the sizes or relative proportions thereof, as such may
and in fact must be varied to suit the circumstances of each particular case,
as the class or tonnage of the ship, and other causes, without at all departing
from the principal of my Invention, which is for the support of the propeller
and its adjuncts; and where I may have given direction to fix any part of my
apparatus in a particular manner or place, it is to be understood only that I
consider that manner or place the best for the purpose; but that I do not
confine myself absolutely thereto, nor do I lay claim to any of the mechanical
parts used in carrying out my improvements when taken merely as parts,
such as rods, screws, or other, and not combined or put together or used
for the purposes of my Invention; which I declare to be, and I claim, the
exclusive use of the combination of parts forming linings or casings, brackets,
carriages, bearings, rods, nuts, and other, forming when so combined in the
manner herein-before described a means of effectually supporting propellers.in
the sterns of ships, and consequently "Improvements in Machinery or Apparatus
for assisting in Propelling Vessels."
In witness whereof, I, the said James Rae, have hereunto affixed my
hand and seal, this Thirtieth day of April, in the year of our Lord One
thousand eight hundred and fifty-five.
Witness,..
JOHN GEDGE, Patent Agent,
4, Wellington Street South, Strand.
JAMES RAE. (L.S.)