IMPROVEMENTS IN STEERING GEAR
Year: 1872

page_text: PROVISIONAL SPECIFICATION left by Douglas Hebson at the Office
of the Commissioners of Patents, with his Petition, on the 30th
April 1872.
I, DOUGLAS HOBSON, of Liverpool, in the County of Lancaster, Con-
sulting Engineer, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN STEERING GEAR," to be as follows (that is to say) :—
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This Invention consists in certain improvements in steering gear for
navigable vessels, whereby the motive power may be applied by hand
or steam, or both combined, in a simple and efficacious manner.
In applying this Invention a pinion is fitted on to the hand steering
wheel shaft, which is capable of being made to revolve with or inde-
pendently of the said shaft, and is arranged to gear with a toothed wheel
on a parallel shaft which carries the chain wheel, and which shaft may
be actuated through a worm and worm wheel, or by a system of toothed
wheels to which motion is imparted by a small steam cylinder or

page_text: '
cylinders placed in any convenient position in proximity thereto. The
steam may be supplied from one of the larger boilers or from the donkey
engine boiler. There is an arrangement for throwing the worm or train
of toothed gear, or their mechanical equivolents, in and out of gear by
means of clutch or other like arrangement, by which the steam power
may be applied or withdrawn at pleasure; the valves of the cylinder
or cylinders being fitted with the link motion or other gear for con-
trolling the action thereof in order to rotate the engine shaft and
steering wheel in either direction.
When it is desired to steer by hand only through the steering wheel
or wheels, the worm wheel or other motion used is thrown out of gear,
and the pinion on the steering wheel shaft is brought into action to
give rotation to the toothed wheel on the chain wheel shaft, which may
then be rotated in either direction without interference with the steam
cylinder or cylinders, or the worm or other motion by which it is or
they are connected to the chain wheel shaft. The motion is conveyed
from the chain wheel to the tiller head and ridder by chains, rods, or
wire rope, with or without the intervention of blocks, rods, or ropes.
When steam power alone is used the pinion on the hand steering wheel
shaft is thrown out of action and the engine shaft thrown into con-
nection with the chain wheel shaft, when it may be rotated in either
direction at pleasure by the steam power. When both steam and hand
power are to be applied for operating the steering apparatus, the con-
nection to the chain wheel shaft is made complete both from the engine
and hand steering wheel shafts, by which motion may then be given to
the rudder through the leading chains and so forth by steam and hand
power.
When it is desired to give motion to the rudder by means of an
ordinar screw steering gear by steam in addition to hand power, or in
lieu thereof, I use such arrangement of worm wheel or toothed wheel
motion as may be suitable in each case to obtain the required relative
velocities between the engine shaft and steering screw shaft, together
with clutch or other ordinary disengaging apparatus, to enable the
engine shaft to be connected or thrown out of action with the steering
screw shaft imparting action to the rudder. That the captain or officer in
charge may know the precise position of the rudder at any time, I use
an ordinary mechanical contrivance for giving motion to a signal hand
or pointer operated from the chain wheel or the steering wheel shafts or

page_text: other convenient moving part of the gear, the position of which pointer
will accurately correspond with that of the rudder. The pointer may be
arranged to travel over the face of a dial plate placed in any convenient
position for observation.