Improvements in Rudders for Vessels.
Year: 1893

page_text: Date of Application, 17th Mar., 1893-Accepted, 6th May, 1893
COMPLETE SPECIFICATION.
Improvements in Rudders for Vessels.
Communicated from abroad by ALEXANDER MCDOUGALL, a citizen of the
United States of America, residing at Duluth, in the County of St. Louis,
and State of Minnesota, one of the United States aforesaid, Ship Builder.
1. WILLIAM FAIRBURN-HART, of the General Assurance Buildings. 1 East
Parade, Leeds, in the County of York, Patent Agent, 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 :-
The particular class of rudders to which the invention relates is balance rudders,
that is to say, rudders having the stock and pintle so placed that about two thirds
of the surface of the rudder is behind the pivoting point and about one-third of
the surface of the rudder is in advance of the pivoting point. By reason of
this construction rudders of this type can be moved more easily than ordinary
rudders for the reason that the surface in advance of the pivoting point will
exactly balance an equal amount of surface behind the pivoting point. Rudders
of this type are also better adapted for use in heavy seas than ordinary rudders,
for the reason that there will be less strain imposed upon the pintle and stock when
the rudder encounters a heavy wave. The principal object sought to be obtained
by the use of my invention is to produce a rudder which can be manufactured
more economically, and which will be lighter and stronger than former rudders.
For a better comprehension of my invention, attention is directed to the accom-
panying drawings forming a part of this Specification in which,
Figure 1, is an elevation partly in section of my improved rudder showing in
dotted lines the method of its application to vessels, and,
Figure 2, a sectional view of the same.
In both of the above views corresponding parts are designated by the same letters
of reference.
A, is a heavy iron or steel frame which is to be cast or worked into the
proper
shape. This frame is provided at its upper portion with a stock B, which may
be either cast in position on the frame or welded or secured thereto in any
other suitable manner. At the lower end of the frame is the usual pintle C,
which bears upon the end of a heavy shoe C', attached to or forming a part of the
keelson, so that there will be sufficient space between the skeeg and the rudder
for the propeller of the boat. The stock B, extends up through the overhang
being mounted therein in any suitable way, and is connected with the usual steering
apparatus. The said stock B, and pintle C, are so mounted that about two-thirds of
the surface of the rudder will be behind the same and about one-third of the
surface of the rudder will be in advance of the same. In this way it will be observed
that the surface in advance of the pintle will exactly balance the same amount of
surface behind the pintle, so that there is much less surface to be actually moved
than in ordinary rudders. Moreover in ordinary rudders any impact of waves will
be thrown on its entire surface so that great strains will be brought to bear upon
the pintle and stock, but in the improved rudder when it is struck by a waves the
balance portion in front of the pintle acts as a cushion, which not only prevents
sharp sudden strains, but also greatly reduces the same. Extending down on
the inside of the frame A, preferably in line with the stock and pintle, is a heavy
metal rib D, which can be inade either integral with the frame or of a separate
piece. D' D' are heavy hard wood planks which are fitted within the frame A,
on each side of the rib Ď, and which are preferably arranged in a vertical position.
These planks are continuous throughout, and are preferably of a gradual
thickness froin each side to the central rib D, as shown in Figure 2. It is also

page_text: desirable that the planks should decrease gradually in thickness from the centre to
the top and bottom. E, E, is a heavy metal covering on each side of the planks D',
which is secured in place by means of rivets or bolts a, a, passing through the edges
of each plate E, and through the outside frame A, and also through the said
rib D.
In order to further strengthen the ruilder I make use of additional bolts or
rivets,, which extend through both plates E, and through the planks D'. When
in use the interior planks D', will swell under the action of the water so as to fit
very tightly within the frame A, and between the plates E.
While the use of
planks arranged in a vertical position is desirable it will nevertheless be understood
that such planks may be dispensed with or any other suitable packing material, such
as concrete, for example, may be placed within the frame A.
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:-
:-
First: An improved rudder having its steck and pintle so mounted with respect
to the body of the rudder that about two-thirds of the surface shall be behind said
pintle and stock, and about one-third of the surface shall be in front of said pintle
for the purposes mentioned.
Second: An improved rudder consisting of a continuous metal frame A, planks D',
within said frame, and outer plates E, riveted to said frame and planks, substantially
as described.
Third: An improved rudder consisting of a continuous metal frame A, provided
with a stock B, and pintle C, and with a rib D; planks D', within said frame
continuous throughout und of a greater thickness at the central part of said planks
thau at the ends thereof, substantially as described.
Dated this Sixteenth March A.D. 1893.
W. FAIRBURN-HART.