IMPROVEMENTS IN RAILWAY TURNTABLES
Year: 1858

page_text: LETTERS PATENT to Brooke Martin and Charles Julian Light, both of
Great George Street, Westminster, in the County of Middlesex, Engineers,
PROVISIONAL SPECIFICATION left by the said Brooke Martin and Charles
Julian Light at the Office of the Commissioners of Patents, with their
Petition, on the 28th April 1858.
We, BROOKE MARTIN and CHARLES JULIAN LIGHT, both of Great George
Street, Westminster, in the County of Middlesex, Engineers, do hereby declare
the nature of the said Invention for "IMPROVEMENTS IN RAILWAY TURNTABLES,"
to be as follows:-
The first of our improvements consists in combining a solid or dead bearing
for railway turntables when not in action, with the use of rollers upon which
they may freely move when required for turning carriages or wagons; these
rollers being at such a level that when the table is on its solid bearings it is
not in any way supported upon them. We propose to obtain this result by
slightly raising the table from its bearings at four or more points at the
circumference, and then gradually lowering it in an inclined direction on to
the rollers, so as to be ready for turning. We prefer to use counterbalance
weights and levers, whether worked by the catches or otherwise, for raising
the table from its bearings, and the same in connection with friction rollers
and properly formed pillows or inclined planes for lowering it on to the
rollers:
Our second improvement consists in keeping the table just free from its
bearings by means of counterbalance weights, or otherwise so arranged as to

page_text: support the weight of the table and turning load, but which will allow it to be
brought to a dead bearing by the weight of a passing train, the table being
lowered on to the rollaws when movined fam
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Brooke Martin and Charles Julian Light in the Great Seal
Patent Office on the 28th October 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, BROOKE
MARTIN and CHARLES JULIAN LIGHT, both of Great George Street, West-
minster, in the County of Middlesex, Engineers, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-eighth day of April, in the year of our Lord
One thousand eight hundred and fifty-eight, in the twenty-second year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto us, the
said Brooke Martin and Charles Julian Light, Her special licence that we, the
said Brooke Martin and Charles Julian Light, our executors, administrators,
and assigns, or such others as we, the said Brooke Martin and Charles Julian
Light, our 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 Isle of Man, an Invention for "IMPROVEMENTS IN RAILWAY TURN-
TABLES," upon the condition (amongst others) that we, the said Brooke Martin
and Charles Julian Light, our executors or administrators, by an instrument
in writing under our, or their, or one of their hands and seals, should par-
ticularly describe and ascertain the nature of the said Invention, and in what
manner the same was to be performed, and cause the same to be filed in the
Great Seal Patent Office within six calendar months next and immediately
after the date of the said Letters Patent.
NOW KNOW YE, that we, the said Brooke Martin and Charles Julian
Light, do hereby declare the nature of our said Invention, and in what manner
the same is to be performed, to be particularly described and ascertained in
and by the following statement:-
The first of our improvements consists in combining a solid or dead bearing
for railway turntables when not in action, with the use of rollers upon which
they may freely move when required for turning; these rollers being at such
a level that when the table is on its solid bearing it is in no way supported by
them. We thus obtain the desideratum of a firm and steady bearing under

page_text: passing trains, while retaining the advantages which rollers possess in
supporting the table and its load during the process of turning. The table
is prepared for use by raising it off its dead bearings at four or more points
on its circumference by means of counterbalance weights, or otherwise, and it
may then be lowered on to the rollers by means of pillow blocks, as berein-
after more fully described, or the rollers themselves may be so connected with
the counterbalance levers as to rise with the table and support it while
turning.
Our second improvement consists in keeping the table just free from its
bearings by means of counterbalance weights, or otherwise, so arranged as to
support the weight of the table and turning load, but to allow it to be brought
down to a dead bearing by the weight of a passing engine; the table being
either lowered on to the rollers when it is required for use by means of pillow
blocks, as in the first part of our Invention, or the rollers being kept in contact
with it in all positions.
The nature of our said improvements may be more fully understood by
reference to the accompanying Drawings Numbers 1 and 2, wherein Figure 1:
represents a plan, and Figure 2 a section of a turntable according to our said
Invention. A is the top or moving part of the turntable, resting when not in
use upon the solid bearings B, B, B, B, and entirely supported by them, so
that no
injury can be sustained by the rollers or roller path from the passage
of trains over the table; when, however, it is required for turning a carriage,.
the lever C is thrown back into the position shewn by the dotted lines, releasing
the counterbalance weight D, which acts through the levers E, E, E, and
friction pullies F, F, F, upon the pillow blocks or double inclined planes G, G,
thus raising the table from its bearings and preparing it for turning. The
form of the pillow blocks causes the table to descend in an inclined direction
when it begins to revolve, and thus enables it to clear the dead bearings
horizontally, and descending slightly below its former level, finally to rest upon
the rollers H, H, upon which it freely turns, until the pillow blocks again
coming into contact with the friction pullies F; cause it to be brought into a
position vertically above the dead bearings, ready to be lowered on to them by
throwing over the lever C to its original position. It will be seen that this
arrangement gives the double advantage of facilitating the turning of the
table at its commencement, and of retarding its motion when the required
point is reached, the inclined planes absorbing the momentum acquired in
turning.
Figure 3 is a plan, and Figure 4 a section of another arrangement according
to cur said Invention. In this the counterbalance levers are made to act

page_text: directly upon the turning rollers, and the friction pullies and pillow blocks are.
dispensed with. When the counterbalance weight D is released in the manner
above described, the levers E, E, lift the rollers H, H, the bearings of which
slide vertically in guides, and thus raising the table from its dead bearings,
cause it to be supported entirely upon the rollers H, H, upon which it freely
turns. Figure 4 shews the table thus raised from its bearings and ready
for use..
In the above arrangements the table is always on its solid bearing, except
when required for turning; but Figure 5 represents the section of a table
constructed according to the second part of our Invention, which is more
especially applicable to goods stations. In this case no preparation is necessary,
as the table is always kept just free from its bearings B, B, by the counter-
balance weight D, acting through levers E, E, and pillow blocks G, similar
to those before described; the solid bearings being only brought into action in
the case of an engine passing over, when the table assumes the position shewn
on the Drawing, the counterbalance weight yielding to the pressure, and
allowing the table to come down upon them. By this means and a small
amount of elasticity afforded by the counterbalance, the rollers are saved from
the heavy shocks so trying to an ordinary turntable.
Having thus described the nature of our said improvements, and in what
manner the same may be applied, we wish it to be understood that we do not
confine ourselves to the precise forms or details shewn on the accompanying
Drawings, as the same may be varied without departing from the principle
thereof; but that we claim,-
Firstly, the combination of solid or dead bearings for railway turntables,
with rollers at or near the circumference, which do not support any part of
the weight except when the table is actually prepared for use.
And, secondly, relieving the rollers of turntables from the weight of a
passing engine, in the manner described and represented in the accompanying
Specification and Drawings.
In witness whereof, I, the said Charles Julian Light, on behalf of the
said Brooke Martin and myself, have hereunto set my hand and seal,
this Twenty-eighth day of October, in the year of our Lord One
thousand eight hundred and fifty-eight.
(L.S.) CHARLES J. LIGHT.