Improvements in and relating to Steering Gear for Steam Ships or other Vessels.
Year: 1891

page_text: Date of Application, 22nd Oct., 1891
Complete Specification Left, 21st July, 1892-Accepted, 27th Aug., 1892
PROVISIONAL SPECIFICATION.
Improvements in and relating to Steering Gear for Steam Ships or
other Vessels.
I, THOMAS MAXWELL GRANT, of the firm of Napier Brothers, Limited,
Engineers, of 100 Hydepark Street, Glasgow, Lanarkshire, do hereby declare the
nature of my invention to be as follows:-
This invention has reference to and comprises certain improvements specially
applicable to the crossheads of rudder steering gear actuated by right and left
hand screws for the purpose of receiving and minimising the shocks or concussions
on these parts caused by the action of the waves or sen on the rudders, and so
prevent breakage of or injury to the rudder spindles or gearing.
One arrangement or combination of the improvements as applied to the cross-
head which actuates the rudder crosshead through connecting rods, with its opposite
slotted arms and bushes for being coupled or yoked by the usual engaging or
disengaging pins to the traversing bushes actuated by the right and left hand
parallel screws, consists in mounting this first bush crosshead loose, within a box
crosshead preferably below it, both mounted loose on the strong stud centre secured
to the deck or lower framing of the steering gear, this lower box crosshead being
connected to the rods which work the fixed rudder crosshead. This box crosshead
has springs fitted within it between its projecting sides and the opposite outer arms
of the bush crosshead mounted within it, which springs may either be in the form
of built bow blade springs, having their central buckles acting on the arms opposite
each other, with pinching screws and jam nuts for tightening up the ends of the
springs, or blocks on them, to any desired strain of spring. Or these bow springs
may be connected by links to the sides of the bush crosshead and box crosshead.
Or instead of bow springs, single or double volute or helical springs, such as used
for buffers, may be mounted on pressing plates between the bush crosshead and the
box-crosshead, with pressing plates and screws for tightening them in position
between the extremities of the two crossheads.
Although the upper crosshead actuated by the gearing has been described as
mounted within and above the crosshead actuating the rudder spindle, the converse
arrangement might be adopted, that is having the box crosshead actuated by
the gearing, either mounted above or below the internal crosshead, and which in
this case would actuate the rudder spindle, in either arrangement the springs
between the crossheads receiving the strain and concussion in actuating the rudder
spindle.
This box crosshead, and springs may be covered in by a screwed-on top protecting
plate, and be fitted with a circumferential web brake. This arrangement of box
crosshead with internal crosshead and springs between them, is also applicable for
being mounted direct on the top of the rudder spindle, without a separate inter-
mediate strong stud. In this arrangement one of the crossheads would be actuated
loose on the rudder spindle by connecting rods direct from the traversing
bushes of the right and left handed screws, either formed on a single or double
screw spindles; while the other crosshead would be keyed or otherwise secured
through the brake wheel to the rudder spindle, so that the rudder would be actuated
through the springs and loose crosshead, by the connecting links and right and left
handed screws.
The internal crosshead in this case would not require slots and
bushes.
Dated the 21st October 1891
W. R. M. THOMSON & Co.,
96, Buchanan Street, Glasgow, Agents.

page_text: COMPLETE SPECIFICATION.
Improvements in and relating to Steering Gear for Steam Ships or
other Vessels.
I, THOMAS MAXWELL GRANT, of the firm of Napier Brothers, Limited,
Engineers, 100 Hydepark Street, Glasgow, Lanarkshire, 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 in writing,
that is to say :-
This invention has reference to and comprises certain improvements specially
applicable to the crossheads of rudder steering gearing actuated by right and left
hand screws for the purpose of receiving and minimising the shocks or concussions
on these parts caused by the action of the waves or sea on the rudders, and so
prevent breakage of or injury to the rudder spindles or gearing.
And in order that my said invention and the manner of performing or carrying
the same into effect or practice may be properly understood I have hereunto
appended an explanatory sheet of drawings in which the same reference letters are
used to indicate corresponding parts in all the figures where shown.
Figure 1 is a sectional elevation and Figure 2 a corresponding plan of one
arrangement of my improved crossheads A, B, springs 6 and mechanism for
actuating through connecting rods C, the rudder spindle Z of ships or vessels, and
Figures 3 and 4 are a corresponding sectional elevation and a plan of my
improved crossheads A B springs, and mechanism for actuating the rudder
spindle Z direct.
Figure 5 shows a plan view of the crossheads A, and B, corresponding to
Figures 1 and 2, but with conoidal or volute springs shown as applied between
them instead of the compound blade springs shown in Figures 1 to 4.
Figure 2 shows a detached plan view of an ordinary double right and left handed
screw arrangement,, for actuating the crosshead A direct through the traversing
screw nuts, ", as shown in Figures 1 and 2, and
Figure 2 shows a similar plan view detached of an ordinary single right and
left handed screw arrangement for actuating the crosshead A, through connecting
rods y, y', from the traversing screw nuts, ", as shown in Figures 3 and 4.
Referring to the arrangement, shown in Figures 1, 2 and 24 of these drawings,
the improvements consist, in mounting the first crosshead A, which has its actuating
bushes A', working in slots Ain the opposite arms of the crosshead A loose
within the box crosshead B, preferably below it, both mounted loose on the strong
stud centre D, secured by a strong basement plate D₁ to the deck or lower
framing Y of or below the steering gear, this lower box crosshead B being
connected to the rods C which work the fixed rudder crosshead Z', keyed on the
top of the rudder spindle Z, as seen particularly in Figure 2. This box cross-
head B, has springs 6 fitted within it between its projecting sides and the opposite
outer arms of the bush crosshead A. mounted within it, which springs b may either
be in the form of built bow blade springs, as shown in Figures 1 and 4, having
their central buckles acting on the outside of the arms of the crosshead A,
opposite each other, and with pinching screws and jam nuts b in the crosshead B,
for tightening up the blocks on the ends of the springs to any desired strain of
spring. The buckles b', may be guided by spindles in the sides of the crosshead B,
as dotted in at 6111, in Figure 2. Or these bow springs may be connected by links
to the sides of the bush crosshead and box crosshead, instead of by the buckle
blocks, and pinching screw 62. Or instead of bow springs, single or double
yolute springs b (or it might be helical springs) such as used for buffers, may, as

page_text: shown in Figure 5 be mounted on pressing plates 6', at their inner ends on the
crosshead A, with pressing plates and screws 61, 63, in the crosshead for tightening
them in position between the extremities of the two crossheads A, B. In the
arrangement shown in Figures 1 and 2 the crosshead A is actuated direct from
the ordinary double right and lef: handed screws z., of the steering gear, shown
to a smaller scale in Figure 24, by the portable removable pins inserted into the
bushes A' of the crosshead A, as seen more particularly in Figure 1, these bushes
oscillating the internal crosshead A, by sliding in their recesses A", so that this
actuates the crosshead B through the springs b, the crosshead B being connected by
pins C' to the connecting rods C, C, which actuate the crosshead Z on the rudder
spindle Z, thus giving a yielding action between the crossheads A, and B, in this
motion to prevent shock or breakage to the ordinary steering gear, whether
actuated by motive power engines or by hand.
Referring to the arrangement shown in Figures 3 and 4, this shows the rudder
spindle Z driven direct by the crossheads A, B, mounted on it without the separate
intermediate strong stud D, as used in the former arrangement. In this arrange-
ment the crosshead A would be mounted and actuated loose on the rudder spindle Z,
within the box crosshead B by connecting rods y, y', direct from the traversing
bushes, 2, of the right and left handed screws z, z, say as formed on the single
spindle of an ordinary steering gear mechanism, as shown to a smaller scale in
Figure 2B while the other box crosshead B would be keyed or otherwise secured
to the top of the rudder spindle Z below the crosshead A, as seen particularly in
Figure 3, or this crosshead may be mounted on a brake wheel secured on the top
of the rudder spindle so that the rudder spindle Z would be actuated through the
springs and loose crosshead B, by the connecting links y, y' and right and left
handed screws z, z', of the ordinary arrangement shown in Figure 20, or it might
be from the ordinary double screws shown in Figure 2ª. The internal crosshead A
in this arrangement Figures 3 and 4, would not require the bushes A' and slots A¹¹,
of the former arrangement.
This box crosshead B, and springs b may be covered in by a top protecting plate,
as shown dotted in at E in Figure 1, screwed on by screw pins at E', and might be
fitted with a circumferential web brake.
Although the upper crosshead A, actuated by the ordinary screw gearing in
these arrangements has been described as mounted within and above the cross-
bead B, actuating the rudder spindle Z, the converse arrangement might be adopted,
that ir, having the box crosshead B actuated by the gearing, either mounted above
or below the internal crosshead A, and which in this case would actuate the rudder
spindle Z, in either arrangement the springs b between the crossheads A, B,
receiving the strain and concussion in actuating the rudder spindle Z.
Although the ordinary right and left hand screw arrangements are shown for
working this improved double crosshead and spring tiller by engine power or by
hand power it is to be understood that it might also be worked by chains as
indicated at z from ordinary motive power screw chain barrel steering gear or by
a chain quadrant and lever on the rudder spindle itself.
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. In steering gear for steam ships or other vessels, the, mounting of a cross-
head loose within a box crosshead and having springs interposed between or
combined with these, substantially as and in the manner and for the purposes herein
described in reference to and shown in the accompanying drawings.
Second. In steering gear for steam ships or other vessels, the arrangement and
combination of the parts of duplex crossheads with interposed springs, either
having these crossheads mounted loose on an intermediate stud, or having one of
them keyed or secured on the rudder spindle and the other mounted loose on same

page_text: and actuated from the screw gear, substantially as and for the purposes herein
described in reference to and shown in the accompanying drawings.
Dated the 20th July 1892.
W. R. M. THOMSON & Co.,
96, Buchanan Street, Glasgow, Agents.