IMPROVEMENTS IN ADDIDIMA BAD SEPORINA CHIDS ANV
Year: 1874

page_text: LETTERS PATENT to William Lister, of 38, Potts Street, Hylton
Road, in the Borough of Sunderland, in the County of Durham,
Manager of a Saw Mill, for the Invention of "IMPROVEMENTS IN
ADDIDIMA
BAD
SEPORINA CHIDS ANV"

page_text: In order to prevent such accidents I interpose springs between the
tiller and the rudder head. The tiller is fixed to a collar, which is able
to turn on the rudder head, to which two spiral springs are attached each
by one end. The springs are coiled in opposite directions, and one is
above and the other below the collar which carriers the tiller. The
springs are contained in cylindrical cases or spring boxes, the outer end
of each spring being fixed to the interior of its box or case.
There are projections upon the spring boxes or cases, one on each, and
the tiller is between the projections. When the tiller is moved from its
midships position either to port or starboard it presses on one or other of
these projections, and carries the corresponding spring box round with
it. The rudder goes with the spring box, except when exposed to a
sudden and undue strain, and then the spring yields and eases the
strain.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Lister in the Great Seal Patent Office on
the 5th March 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
LISTER, of 38, Potts Street, Hylton Road, in the Borough of Sunder-
land, in the County of Durham, Manager of a Saw Mill, send greeting:
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fifth day of September, in the year of our
Lord One thousand cight hundred and seventy-four, in the thirty-eighth
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said William Lister, Her special license that I, the
said William Lister, my exccutors, administrators, and assigns, or such
others as I, the said William Lister, my executors, administrators, and
assigns, should at any time agree with, and no others, from time to
time and at all times thereafter during the term therein expressed,
should and lawfully might make, use, exercise, and vend, within the
United Kingdom of Great Britain and Ireland, the Channel Islands, and

page_text: them, but should the rudder be exposed to any sudden or undue strain
the springs yield, and the strain is eased. I would remark that in place
of the casing being formed to receive two springs only it might, where
greater strength of spring is required, be made to contain a larger
number of springs, each having their separate abutments, and the
collar of tiller be formed with a corresponding number of arms to bear
against the several springs. In cases also where the rudder is worked
by a yoke or cross head, which acts the part of a tiller, such yoke or
cross head may similarly have springs interposed between it and the-
rudder head.
Figure 1 shews a plan view of the casing A; Figure 2 shews a plan.
view of the casing with springs and tiller in position; Figure 3 shews a
side view of the tiller; Figure 4 shews a plan view of the cover for the
casing Figure 5 is a plan view of the tiller and casing, with the cover
on; Figure 6 is an elevation of the same shewing a fast collar on top of
rudder head to keep the tiller in place; Figure 7 is a section taken
through the line c, d, Figure 5, and Figure 8 a section taken through
the line a, b, in the same Figure.
Another arrangement for interposing springs between the tiller and
rudder head is shewn at Figures 9, 10, 11, 12, 13, and 14. Figure 9 shews
a side view of the rudder and tiller; Figure 10 shews a plan view of the
same; Figure 11 shews on a larger scale a front elevation of the tiller.
and its connections with the rudder head; Figure 12 shews a vertical
section of the same; Figure 13 shews horizontal section taken on the
line a, b, Figure 9; and Figure 14, a horizontal section taken on the
line c, d, in the same Figure. In these Figures A is the tiller fixed to a
collar which is capable of turning around the rudder head B; C, C, are
spiral springs, each attached at one end to collars keyed to the rudder
head. The springs are coiled in opposite directions, and are contained
in cylindrical cases or spring boxes D, one of which is above the collar
to which the tiller is fixed, and the other is below it, and the outer end
of each spring is fixed to the interior of its box or case. There are
projections E on each of the boxes, and the tiller lies between them.
When the tiller is moved from its midships position, either to port or
starboard,. it presses on one or other of these projections, and carries the
corresponding spring box round with it, except when the rudder is
exposed to any undue strain; the spring in the spring box then yields
and eases the strain. As before stated springs may be provided in

page_text: stantially as herein described.
2. Interposing springs between the tiller or yoke and the rudder head,
substantially as herein described and illustrated in the Drawings
annexed.
In witness whereof, I, the said William Lister, have hereunto
set my hand and seal, this First day of March, in the year of
our Lord One thousand eight hundred and seventy-five.