Improved Means for Steering Screw-steamers and other Vessels.
Year: 1887

page_text: Date of Application, 29th Apr., 1887
Complete Left, 8th Dec., 1887
Complete Accepted, 13th Jan., 1888
Improved Means for Steering Screw-steamers and other Vessels.
I, GEORGE HOWARD HARRISON, of Great George Street, in the City of
Westminster, Civil Engineer, do hereby declare the nature of this Invention to be
as follows:
This invention relates to improved means applicable for use in steering vessels
propelled by screws operated by steam or other motive power, or designed to be
worked upon the 'hydraulic propulsion principle.
In applying my invention to a screw-vessel, I employ two rudders, one arranged
on each side of the screw. The two rudders may be mounted rigidly in a frame
pivotted above and below the line of the screw-shaft; or each rudder may be
separately pivoited, means being provided for coupling the respective rudder-posts to
a common tiller whence the rudders are worked in unison. In either case, the
rudders, which may be of the balanced or unbalanced type, constantly remain
parallel with one another; and are so arranged that when thrown over to an extreme
angle of inclination, the action of the screw-propeller is not interfered with.
Owing to the rudder being placed on either side of the screw-propeller, the stream
of water set in motion by the action of the propeller is confined in a channel bounded
below by the water and laterally by the inner surfaces of the rudders. The direction
of this channel, relatively to that of the vessel's keel, is varied by the movement of
the rudders towards either one quarter or the other of the vessel, with the effect that
the stern of the vessel is caused to move in the opposite direction, highly effective
means for steering being thus afforded.
When the hydraulic system of propulsion is employed and a siream of water is
ejected from the stern of the vessel, the same is caused to pass between a pair of
rudders, substantially in the same manner as the screw-race hereinbefore referred to,
similar results being attained.

page_text: In large vessels fitted with twin screws-that is to say, screws carried by parallel
shafts mounted some distance apart-I prefer to employ a series of three rudders;
one of these being placed outside each of the propellers, and the third between the
two propellers; the three rudders being worked in unison, as before described. In
some instances however, particularly with twin-screw vessels of the lighter class, each
propeller may be furnished with a pair of rudders mounted in either of the inodes
herein before described; there being under such circumstances four rudders employed,
each of greatly reduced area but collectively of superior efficiency in comparison with
the large and costly single rudders at present in common use.
TIL AL 1
11007
G. G. M. HARDINGHAM,
191, Fleet Street, London, E.C.,
Agent for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improved Means for Steering Screw-steamers and other Vessels.
1, GEORGE HOWARD HARRISON, of 4, Great George Street, in the City of
Westminster, Civil 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 improved means applicable for. use in steering vessels
propelled by screws operated by steam or other motive power.
And in order that my invention and the mode of carrying the same into effect may be
fully understood, I will proceed to describe the same with the aid of the accompanying
drawings; whereof Fig. 1 is a side elevation, Fig. 2 an end elevation and Fig. 3 a
plan view of the under side of a portion of a screw-vessel to which my improved
ineans for steering are applied.
The vessel a is provided with two rudders, one arranged on each side of the
screw-propeller c. The two rudders are mounted rigidly in a frame such
as d pivotted at e. If desired, the frame d may be formed with two return-branches
and be carried in an additional bearing arranged below the propeller c. Or, the
frame d may be partially constructed of plate metal, in which case prefer to form it
of arch shape; the sides of the arch being rivetted or otherwise fastened to the rudder-
plates, and the crown of the arch serving to confine the water above the propeller.
The rudders, which may be of the partially balanced type, as illustrated, or unbalanced,
constantly remain parallel with one another; being at the same time so arranged that
when thrown over to an extreme angle of inclination they do not interfere with the
action of the screw-propeller.
Owing to one of the rudders being placed on each side of the screw-propeller, the
stream of water set in motion by the action of the propeller is confined in a channel
bounded below by the water and laterally by the inner surfaces of the rudders. As
will be readily perceived on reference to Fig. 4, wherein the rudders are represented
in an oblique position and in dotted lines at an extreme angle of inclination, the
direction of the above mentioned channel relatively to that of the vessel's keel is
varied by the movement of the rudders towards either one quarter or the other of the
vessel, with the effect that the stern of the vessel is caused by the reaction of the
screw-race to move in the opposite direction; highly effective means for steering or
manoeuvring being thus afforded.
With twin screw-vessels, each propeller is furnished with a pair of rudders mounted
to work about a common centre as herein before described; there being under such
circumstances four rudders employed, each of greatly reduced area but collectively of
superior efficiency in comparison with the large single rudders hitherto employed
under similar circumstances.

page_text: Having thus particularly described and ascertained the nature of this invention,
and in what manner the same is to he performed, I would have it known that I do
not clain broadly the use of two rudders respectively arranged on opposite sides of
the propeller, or of two rudders placed one in advance of the other; but I claim :-
1. For steering vessels, the use of two rudders arranged on opposite sides of the
propeller and mounted upon a centrally pivotted frame, by means of which the
rudders are moved bodily and in unison for the purpose of deflecting the stream of
water set in motion by the propeller.
2. Mounting a pair of rudders upon a centrally pivotted frame, so that, instead of
pivotting on their respective centres, they move bodily about the pivot of the main
frame, substantially as herein described.
Patou tub
oun uay or December 1007.
G. G. M. HARDINGHAM,
191, Fleet Street, London, E.C.,
Agent for the Applicant.
G. G. M. HARDINGHAM,
191, Fleet Street, London, E.C.,
Agent for the Applicant.