IMPROVEMENTS IN SHIP-STEARING GEAR
Year: 1884

page_text: I, WILLIAM PHILLIPS THOMPSON Fel. Inst. P.A. of the Agency for Foreign
Patent Solicitors 6 Lord Street Liverpool in the County of Lancaster and 323 High
Holborn in the County of Middlesex do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN SHIP-STEARING GEAR" 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 improvements in ship steering devices adapted to be
operated by hand or otherwise, the object being to provide mechanism connected
with the rudder by chains, ropes, gearing or other suitable means, of such power
that ordinarily one man only is required to control and operate it, and which is
constructed to of itself hold the rudder in any position to which it may have
been turned, or against any strain of currents or waves-without locking it, and
independent of any power exerted upon the wheel, and yet which is always free to
be operated without delay.
In the Drawing forming part of this Specification, Fig. is a perspective view
showing a portion of a ship's deck together with the upper end of the rudder post,
and of steering devices geared to the latter embodying the improvements.
Fig. 2 is a side elevation partly in section.
Fig. 3 is a front view partly in section of parts of the operating mechanism.
Fig. 4 is a perspective view illustrating the improvements connected with the
rudder post by chains and tiller.
The mechanism of this device which is connected with the ordinary steering
wheel of a vessel and its shaft, and with the rudder by gearing chains or other-
wise, embodies devices for transmitting differential rotary motion, as hereinafter
described.
The said mechanism consists of the perforated dise F, having a hub g thereon to
which is fixed a gear a. Also of a pinion y located by the side of said disc and
carrying on one of its faces a series of studs b which enter the perforations in
disc F; also of an eccentric n fixed on the wheel shaft c, which when said shaft is
turned carries the pinion y around in an eccentric path; and also of an internal
D G

page_text: .
gear w with which the teeth of said pinion engage, and whereby when the latter is
carried around eccentrically as aforesaid said pinion is caused to rotate giving
rotary motion to the disc F and gear a. The rudder post B stands up through the
deck A as usual, and has secured to it a geared segment D with which the gear a
engages.
The wheel shaft c having secured on it the usual steering wheel m has its rear
end supported in a suitable bearing on the standard E, which is bolted to the
deck A in the rear of the rudder post B.
The internal gear w partly. within which the disc F and pinion y operate, is
supported in a yoke frame h which. is bolted to the deck in front of the rudder
post.
The internal gear w has upon its outer face two studs, z z, opposite each other
upon which are placed heavy rubber springs t of cylindrical form. Sockets v, v, are
made in the yoke frame to receive the said studs and rubber springs, the yoke
frame encircling and supporting gear w and the parts within and passing
through it as shown in Fig. 2. The operation of the above described devices is as
follows:-
When shaft c is turned by wheel m, the eccentric n carries the pinion y around
rolling it against the teeth of gear w, and giving it a rotary motion on the said
eccentric. As aforesaid the studs 6 on the rear face of pinion y-engage in the
perforations 7 of the disc F, causing the latter and gear a on the hub of said disc
to be rotated, and since the gear a engages with the geared segment D on the rudder
post B, the latter and the rudder are thereby turned in either direction by turning
wheel m.
The turning of the eccentric n in pinion y gives a rotary motion to gear a, but
no amount of force exerted upon said gear by the rudder post can rotate it, for the
disc F is by said force turned against the studs b on pinion y and the axis of the
latter is eccentric to that of the disc F, and the periphery of said pinion engages
with the teeth of the internal gear w, therefore the force of the rudder cannot
rotate the parts so long as the internal gear is held so that it cannot turn in
frame h.
The purpose of the springs t.on the studs z of the gear wis to provide cushioned
bearings for said studs, to relieve the parts somewhat from the great force of the
waves when they strike the sides of the rudder and give a twisting movement to
the rudder post.
It will be understood from the above description that the rotary motion of the
disc F is less rapid than that of wheel m, about one to five more or less, and that
the differential mechanism itself leaving wheel m 'free, firmly holds the rudder in
any position to which it may be turned.
Fig. 4 illustrates the application of the differential mechanism to a rudder post
provided with a tiller D and the usual chain c2 running through the roller blocks e
on the deck A to the hub g. In this construction the rear end of shaft c is
supported in a swivel bearing in the end of the rudder post B. The yoke frame h
is the same as in Fig. 1.
The operating mechanism in Fig. 4 is identical with that above described in
connection with Figs. 1 and 2 excepting that the hub g is enlarged to make it a
proper size for a chain drum on which to wind chain c³, the gear a and segment D
being dispensed with.
The within described differential mechanism, arranged to give motion to a drum
as shown in Fig. 4, upon which to wind a chain or rope, constitutes a very effective
capstan, when placed in the usual vertical position on a ship's deck, and, provided
with suitable means for turning the same.
.
Having now particularly described and ascertained the nature of the said
Invention, as communicated to me, and in what manner the same is to be
performed, I declare that what I claim is :-
1st. In combination with the wheel shaft c, eccentric n, and the rudder post B,
the perforated disc F having hub g thereon, the pinion y having studs b thereon,

page_text: the internal gear w, and means substantially as described to hold the latter and
prevent it from rotating, and mechanism, substantially as described, connecting the
hub g and the rudder post B, substantially as set forth.
2nd. In combination the yoke frame h, having the sockets the internal gear w,
having the studs to enter said sockets, the springs t, the wheel shaft c, the
eccentric n, pinion y, disc F, the rudder post B, and means substantially as
described for connecting the hub g, and the rudder post, substantially as set
forth,