Improvements in Mechanism for Controlling the Movements of Ships' Rudders.
Year: 1892

page_text: Date of Application, 18th Oct., 1892-Accepted, 18th Feb., 1893
COMPLETE SPECIFICATION.
Improvements in Mechanism for Controlling the Movements of
Ships' Rudders.
I JORGEN CHRISTENSEN, of No. 426 Montgomery Street, in the City and County
of San Francisco, State of California, United States of America, Master Mariner,
do hereby declare the nature of my invention and in what manner the same is to be
performed to be particularly described and ascertained in and by the following
statement:-
My invention has for its object mainly to relieve the ship's rudder and its steering
gear from the shocks and strains produced by abrupt movements of the rudder under
the blows of the waves or the action of rough water, and thereby to lighten the
labors of the men at the wheel as well as to reduce the risks of accidents that usually
attend the work of holding the ship to its course in rough weather.
To such end and object my invention consists of certain novel construction and
combination and arrangement of hydraulic cylinder and mechanism connecting the
same with the tiller on the rudder-post of a ship as hereinafter fully described and
set forth.
The following description explains the nature of my said improvements and the
manner in which I apply and carry out the same, the accompanying drawings
that form part of this Specification being referred to herein by figures and
letters:
a
The principal points or features of my invention comprise an hydraulic cylinder
filled with liquid, such as water or oil, a piston movable in the cylinder having
piston-rod extending through the end or head to the outside and suitable means or
mechanism by which direct and positive connection is made between this rod and
the tiller or the rudder-head in such manner that the piston is moved in its cylinder
by the movement of the tiller and the piston in its turn checks and otherwise
controls the movement of the tiller or the rudder-head.
Ports and passages connect the cylinder-space on one side of the piston with the
corresponding space on the opposite side of the piston, and by a valve or similar
means the area of the passage between the two ends of the cylinder is increased or
reduced or is closed entirely for the purpose of regulating the flow of the liquid
through the passage from one side to the other side of the piston or of shutting it
off altogether.
In the accompanying drawings I have illustrated one mode of constructing and
applying my said invention to a rudder of ordinary size and where the shocks and
strains to be resisted by the device are not severe or excessive and where sufficient
And in addition to
breadth of deck space in frout of the rudder-post is afforded.
this I show a mode of extending and applying my invention to ships of large size
and in situations where the space in front of the rudder-post on the deck is not
sufficiently wide to accommodate the other form of device.
Figures 1, 2, and 3 represent the manner in which I construct and arrange a
single long cylinder to control a ship's rudder.
In these views
Figure 1 is a plan or top view of the mechanism with the tiller removed from the
rudder-post.
Figure 2 is an elevation taken from the left hand side of Figure 1 showing the
tiller in place on the rudder-head.
Figure 3 is a longitudinal section taken through the center of the cylinder.
Figure 4 is a detail view in section showing the construction of the collars on the
rudder-head.

page_text: Figure 5 is a top view of another construction in which two short cylinders set
longitudinally in front of the rudder-head are employed in the place of the single
cylinder.
Figure 6 is a side elevation of the left-hand cylinder in Figure 5.
Figure 7 is a horizontal section taken longitudinally through the cylinder to show
the ports and connecting passage at one side.
In Figures 1 to 3 inclusive A indicates the hydraulic-cylinder, B its piston, and
B' the piston rod. C is a bar having a central toothed portion or rack C. D is a
toothed segment secured on the rudder head W and taking the teeth of the rack C¹.
The ends of the piston-rod are directly attached to the ends C² of the rack which
are suitably bent to take the rod. a is a port in the side of the cylinder near one
head and a¹ is a corresponding port near the other head from which a connecting
pipe or passage A2 extending along the side of the cylinder connects with the
opposite port a. Mid-way in the length of this pipe is a valve A³ with ways or
passages controlled by a rotary plug. An opening in the top of the valve-body
has a short stand pipe A* extending upward to about the top of the cylinder body,
and one passage of the plug is arranged to control the flow of liquid through the
pipe A from one side of the valve to the other, while the remaining passage or
opening in the plug when properly set is arranged to bring the stand-pipe A into
connection with the pipe A' so that the cylinder can be filled and liquid introduced
by that means through the stand-pipe from time to time to replace whatever is lost
by leakage. The stand-pipe is closed by a screw-cap and the valve is furnished
with a hand-wheel or lever for setting it.
The toothed-segment D is secured to the rudder-head by a ring or hub D' which
is part of the segment, and is set between two flanged collars E, E, which are
bolted to the rudder head. The hub of the toothed-segment is fitted on the rudder
head to turn between the collars E, E, but is locked by bolts or pins F inserted
through holes in the collars and in the toothed-segment. By drawing out these pins
the toothed-segment is detached from the fixed collars so that the rudder-head can
turn loosely in the segment. The whole mechanism is thereby unshipped or thrown
out of action or by replacing the pins the segment is locked to the head. This
construction furnishes a simple means of throwing the mechanism into and out of
action without disconnecting any of its working parts.
The tiller T is fixed on the head of the rudder-head to swing over the cylinder
where there is sufficient room afforded beneath the tiller, or the mechanism is set
and applied as the space and other conditions may best permit.
The length of the segment D, the size of the piston and the length of stroke are
governed by the size of the rudder and the power which it will require to control
its movements and therefore no exact dimensions are given herein to be followed in
applying and operating my said invention.
When properly constructed and applied the piston will act to check and control
sudden or abrupt movements of the rudder and take the strain in a considerable
degree from the steering gear, as the piston can move in its cylinder in either
direction only as rapidly as the confined liquid is allowed to pass from the cylinder-
space in front of the piston into the space behind it.
Figures 5, 6, and 7 represent a construction in which two short cylinders are
substituted for a single long cylinder, and the piston-rods are directly connected to
the rudder head on opposite sides of the center. The cylinders A, A, are set in
front of the rudder-head on a bed-plate V which is bolted down to the deck and
the cylinders are pivoted to this bed-plate at the front end while they are free to
move in limited arcs from side to side on these pivots as centers.
The ends of the piston-rods B B' that work through the heads of the cylinders
are attached to arms D2 D2 formed integral with the collar rigidly secured to the
rudder-head W. The ends of the piston-rods are attached to the ends of these arms
by bolts or pins as shown to form a loose joint.
A' A are ports in the side of the cylinder at or near the ends and A' is a
connecting-pipe or passage along the side of the cylinder from one port to the

page_text: other. A is a valve in this passage of suitable character to open and close the
passage between one port and the other, see Fig. 7.
A is a lug on the end of the cylinder with a hole to take a short-post or upright
pin A secured to the deck, on this pin as a pivot the cylinder is free to swing in an
arc, V is a bed-plate or block bolted to the deck in front of the rudder-post to carry
the pins A and furnish necessary support under the cylinder to keep the piston-rod
in line. V is a segment-track or way standing above the bed-plate under the outer
end of the cylinder on which the bottom of the cylinder rests.
In the arrangement shown in Figure 5 the two cylinders are mounted on one
bed-plate and the piston-rods are connected to the rudder-head on opposite sides of
the center.
As thus constructed the device is put in working condition by filling the cylinders
with liquid through the opening A provided for that purpose in the top of each
cylinder and then closing the opening. Liquid is also introduced from time to time
through the same opening to replace the loss by leakage.
A greater or less degree of resistance to the movements of the rudder is produced
by turning the valve A³ in the proper direction either to reduce or to increase the
area of the liquid-passage or the rudder can be locked and held at any point by
shutting the valve.
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 device for controlling ships' rudders a cylinder containing a body of
liquid a piston movable in said cylinder and separating the liquid into separate
bodies ports and passages connecting one end of the cylinder space with the other
end around the piston a valve in said passage adapted to regulate the flow of
the liquid through the same a piston-rod extending through both ends of the
cylinder and connected by a bar having a rack or toothed-portion and a toothed-
segment fixed to the rudder-head and engaging said rack combined for operation as
set forth.
2. In combination with a ships' rudder the toothed-segment having a hub or
ring fitted loosely over the rudder-head the flanged collars fixed to the head above
and below the ring and the holes and pins as a means of locking the segment to
the head in combination with the rack the piston-rod connected to said rack the
piston-cylinder piston and passage connecting one end of the cylinder space with
the other end around the piston substantially as specified.
3. The combination with the rudder-head of a vessel of an arm D³ projecting
from the head the hydraulic cylinder A piston B piston-rod B' attached to the
arm D of the rudder-head the ports and passages A' A² connecting together the
liquid-holding space on opposite sides of the piston and the valve A³ in the passage
between said ports the cylinder being attached at the outer end to a fixed point in
front of the rudder head and capable of swinging laterally on said point as a center
in an arc to follow the angular movements of the arm in the rudder-head substantially
as hereinbefore described.
4. The herein described device for controlling ships' rudders consisting of the
hydraulic cylinders A, A, having pistons with piston-rods working through the front
ends or heads the projecting arms D' on opposite sides of the rudder-head having
the piston-rods attached to their outer ends the ports and passages connecting the
ends of each cylinder around its piston and the controlling valve in said passage
the stationery bed and the posts to which the ends of the cylinder are attached to
move in horizontal arcs constructed and combined for operation as set forth.
DL: 10th santahan 1000
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.