in Light Houses and Light Vessels.
Year: 1885

page_text: in Light Houses and Light Vessels.
We, JOHN HOPKINSON, F.R.S. of 4 Westminster Chambers in the City of
Westminster and JAMES KENWARD F.S.A. of Eddystone House, Harborne, in the
County of Stafford, Engineers, do hereby declare the nature of said Invention for
"IMPROVEMENTS IN CLOCKWORK FOR ROTATING THE OPTICAL APPARATUS IN
LIGHTHOUSES AND LIGHT VESSELS" to be as follows:-
Our Invention relates to rendering the machinery which keeps in motion the
optical apparatus of revolving lights whether on shore or afloat more compact and
convenient by using a spring or springs as motive power instead of a weight. It
is most advantageously applied to light vessels as the use of weights as the motive
power there renders necessary a long shaft from below the deck to the lantern on
the mast, whereas by our invention we are able to place the clock work in the
lantern but our invention may also be sometimes applied with advantage in light-
houses. In order to render the clockwork capable of driving the apparatus for a
sufficiently considerable time when necessary we use a series of driving springs
connected to each other in succession; by this means we obtain all the advantages
of a very large drum and long spring in a more compendious form. When the
attendant does not remain in the lantern but is stationed below we provide an
endless chain passing over a pulley upon the clock whereby he is enabled to wind
up the clock from below whenever convenient to himself. In all cases uniformity
of motion is obtained sufficiently accurately by the use of a powerful centrifugal
governor notwithstanding the variable power of the spring but it is well to provide
a bell which shall ring when the power becomes insufficient; this is done on the
centrifugal governor which causes the bell to ring or other signal to be given 80
soon as the power is so reduced that there is no retarding friction called into play
by the governor.
By the use of our invention in Light vessels or floating lights we secure a better
form of power in rough weather and effect a great saving in manual labour in
winding, owing to friction in the long shaft which is usually fixed upon the mast.
In lighthouses the use of our Invention obviates the necessity of providing a trunk
for the descent of weights which is occasionally an inconvenience.
J. HENRY JOHNSON,
Agent for the said John Hopkinson and
James Kenward.

page_text: in Light Houses and Light Vessels.
We JOHN HOPKINSON F.R.S. of 4 Westminster Chambers in the City of
Westminster and JAMES KENWARD F.S.A. of Eddystone House Harborne in the
County of Stafford, Engineers do hereby declare the nature of this invention
and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement :-
Our Invention principally relates to rendering the machinery which keeps in
motion the optical apparatus of revolving Lights whether on Shore or afloat inore
compact and convenient by using a spring or springs as motive power instead of a
weight. Our Invention is most advantageously applied to light vessels as in such
vessels the use of weights as the motive power renders necessary a long shaft from
the deck or from below the deck to the lantern on the mast whereas by our
Invention we are able to place the clock work in the lantern, but our Invention
may also be sometimes applied with advantage in Lighthouses. In order to render
the Clockwork capable of driving the apparatus for a sufficiently considerable time
when necessary we use a series of driving springs connected to each other in
succession, by this means we obtain all the advantages of a very large drum and
long spring in a compendious form. When the attendant does not remain in
the lantern but is stationed below we provide an endless chain passing over a
pulley upon the Clock work, whereby he is enabled to wind up the Clock work
from below whenever convenient-In all cases uniformity of motion is obtained
with sufficient accuracy by the use of a powerful Centrifugal governor notwith-
standing the variable power of the spring but it is well to provide a bell or other
signal which shall ring or otherwise indicate when the power becomes insufficient,
this is done on the Centrifugal Governor which causes the bell to ring or other
signal to be given so soon as the power is so reduced that there is no retarding
friction called into play by the Governor.
By the use of our Invention in light vessels or floating lights we secure a better
form of power in rough weather and effect a great saving in manual labour in
winding up the Clock work owing to the absence of friction of the ordinary long
shaft which is usually fixed upon the mast. In both lighthouses and Light Vessels
the use of our Invention obviates the necessity of providing a trunk for the descent
of weights which is occasionally an inconvenience.
And in order that our said Invention may be fully understood we shall now
proceed more particularly to describe the same and for that purpose shall refer to
the several figures on the annexed sheets of drawings the same letters of reference
indicating corresponding parts in all the figures.
Figure shews partly in elevation and partly in section a light vessel lantern
and catoptric apparatus provided with Clockwork constructed and arranged
according to our Invention for maintaining the rotation of the optical apparatus
Figure 2 shews the arrangement of the revolving carriage on a larger scale in part

page_text: elevation and part section. Figures 3 and 4 give two other views of the Clock
work apparatus figure 3 being seen at right angles to Figure 1 and figure 4
shewing the opposite side to that shewn in Figure 1. Figure 5 shews in section
the arrangement of the main driving springs Figure 6, 7 and 8 shew the details
of the Governor. In all the figures corresponding letters indicate corresponding
parts of the apparatus a a is the mast upon which the lantern is hoisted. This
lantern is constructed in the usual way with a central tube a² to which according
to our improved arrangement we attach brackets b b on which we place our
improved clock work for driving the optical apparatus through the vertical shaft c
and revolving carriage-The rope d d is intended to operate the apparatus by hand
from the deck. The clock work may consist of any suitable or convenient gearing
such as is usual for this purpose but instead of using weights as the motive power
we use a spring or springs contained in the casing e and preferably made compound
as shewn clearly in Figure 5 consisting of separate lengths or coils f. g. h. contained
in a casing made up of the separate parts i. j. k. l the part i being fixed to the
winding spindle m and the other parts j k l being loose on the said spindle. The
inner end of the spring fis fixed to the boss of the part i and the outer end of
the said spring is fixed to the rim of the part j-The inner end of the spring g is
fixed to the boss of the part j and the outer end of the said spring is fixed to the
rim of the part -The inner end of the spring his fixed to the boss of the part k
and the outer end of the spring is fixed to the rim of part which has on it the
teeth for the Clockwork-We thus obtain the advantages of a long spring and a
large drum in a very compact form. It will be evident two three or more lengths
or coils of springs can be used as desired-n is a hand wheel by which the clock-
work can be wound up in the lantern and p is a chain by means of which the
winding up can be done from below. It is shewn as an endless weighted chain as
being the best suited to the purpose-q is the casing of the governor shewn to a
larger scale in Figures 6, 7 and 8. It is provided with means for giving a signal
when the speed becomes too much reduced thereby indicating that the clockwork
requires winding up. The Governor shewn is what is known as a Hight's
Governor although any other analogous kind of Governor may be employed.
Instead of making the ring r, upon which the friction pieces & bear to retard
excessive motion stationary, we make it capable of a movement of partial rotation
under the action of the said friction pieces. As here shewn the said ring ris
formed with a boss which can turn in the seat tits motion being limited by the
pin and slot t. Thus when the friction pieces s bearing on the ring they
cause it to turn until the pin comes against the opposite end of the slot t² and it
is kept in that position until the power decreases to such an extent that the
friction pieces s leave the ring r and allow it to return to its normal position under
the action of any suitable spring or equivalent device and this movement of return
can be utilized in any way to sound a bell or otherwise give a signal. It will be
evident that the details can be varied without departing from the nature of our
Invention.
Having now particularly described and ascertained the nature of our said
Invention and in what manner the same is to be performed we declare that what
we claim is
First. In a lantern for a Light vessel, the combination and use for rotating the
optical apparatus, of clockwork driven by a spring or by springs, and fixed in the
lantern itself substantially as and for the purposes herein before described.
Second. In clockwork for rotating the optical apparatus of Lighthouses and
Lightvessels the arrangemet of successive driving springs substantially as and for
the purposes herein described.
Third. The combination with the centrifugal governor, of clockwork for the
purposes described, of means for automatically indicating when the clock work
requires rewinding substantially as herein described.

page_text: Fourth. In combination with the subject matter of the preceding first claiming
clause the means for winding the clockwork by a chain from the deck or below the
deck of the Light vessel.
Fifth. The general arrangement and combination of parts constituting the
apparatus substantially as and for the purposes hereinbefore described and as
illustrated in the accompanying drawings.