IMPROVE- MENTS IN APPARATUS FOR WORKING POINTS AND SIGNALS OF RAILWAYS
Year: 1864

page_text: LETTERS PATENT to Henry Wadkin, Gas Manager, of the Parish of
St. John, in the City of Chester, for the Invention of "IMPROVEMENTS IN
37
Sealed the 13th October 1864, and dated the 21st April 1864.
PROVISIONAL SPECIFICATION left by the said Henry Wadkin at the
Office of the Commissioners of Patents, with his Petition, on the
21st April 1864.
I, HENRY WADKIN, Gas Manager, of the Parish of St. John, in the City
of Chester, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN APPARATUS FOR WORKING POINTS AND SIGNALS OF RAILWAYS," to be as
follows:-
The points and signals of railways are now frequently worked from stations
at such distances from the same that the connecting rods require to be of great
length. These rods expand and contract to such an extent through variations
in the temperature of the atmosphere that they have to be adjusted frequently
in order that the points and signals should work accurately.
Now my Invention has for its object the so arranging of such long connecting
rods that the points and signals shall at-all times work accurately without any
adjustment of the connecting rods being requisite, and consists in dividing
such rods into two or more parts, and in introducing at such points of division
a lever to which the contiguous ends of the parts of the rod are hinged, and
which lever moves on a fulcrum situated between the two points of attachment
of the rod, so that as the one part of the rod expands or contracts in one:

page_text: direction, and the other part expands or contracts in the contrary direction,
they will move the said lever to a certain extent in one and the same direction,
and the expansions and contractions of the parts will consequently always
counterbalance each other. If the parts into which the rods are divided are
of equal length, then it is evident that for their expansions or contractions to
be counterbalanced in a perfect manner the ends of the same must be attached
to the lever at equal distances from its fulcrum. If the parts of the rod are
of unequal length, then the distances of their points of attachment to the lever
from the fulcrum of the same must be in proportion to the respective
lengths.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Henry Wadkin in the Great Seal Patent Office on the 19th
October 1864.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
WADKIN, Gas Manager, of the Parish of Saint John, in the City of Chester,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-first day of April, in the year of our
Lord One thousand eight hundred and sixty-four, in the twenty-seventli
year of Her reign, did, for Herself, Her heirs and successors, give and grant
unto me, the said Henry Wadkin, Her special licence that I, the said Henry
Wadkin, my executors, administrators, and assigns, or such others as I, the
said Henry Wadkin, my executors, administrators, and assigns, should at any
time agree with, and no others, from time to time and at all times there-
after 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 "IMPROVE-
MENTS IN APPARATUS FOR WORKING POINTS AND SIGNALS OF RAILWAYS,"
upon the
condition (amongst others) that I, the said Henry Wadkin, my executors or
administrators, by an instrument in writing under my, or their, or one of their
hands and seals, should particularly 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 I, the said Henry Wadkin, do hereby declare the
nature of the said Invention, and in what manner the same is to be performed,

page_text: to be particularly described and ascertained in and by the following statement
thereof, reference being had to the accompanying Drawing, and to the figures
and letters marked thereon; that is to say :-
The points and signals of railways are now frequently worked from stations
at such distances from the same that the connecting rods require to be of great
length. These rods expand and contract to such an extent through variations
in the temperature of the atmosphere that they have to be adjusted frequently
in order that the points and signals should work accurately.
Now my Invention has for its object the so arranging of such long connecting
rods that the points and signals shall at all times work accurately without any
adjustment of the connecting rods being requisite, and consists in dividing such
rods into two or more parts, and in introducing at such points of division a
lever, to which the contiguous ends of the parts of the rod are hinged, and
which lever moves on a fulcrum situated between the two points of attachment
of the rod, so that as the one part of the rod expands or contracts in one
direction, and the other part expands or contracts in the contrary direction,
they will move the said lever to a certain extent in one and the same direction,
and the expansions and contractions of the parts will consequently always
counterbalance each other. If the parts into which the rods are divided are
of equal length, then it is evident that for their expansions or contractions to
be counterbalanced in a perfect manner the ends of the same must be attached
to the lever at equal distances from its fulcrum. If the parts of the rod are
of unequal length, then the distances of their points of attachment to the
lever from the fulcrum of the same must be in proportion to the respective
lengths.
On the accompanying Drawing are shewn arrangements for carrying my.
Invention into practice.
Figure 1 shews an elevation, and Figure 2 shews a plan of one arrange-
ment. A, A, is the switch, worked from the lever B by means of the rod C, C;
this rod, instead of being in one piece, as heretofore, is divided in the middle
of its length, and one end of each part is attached to the opposite extremities
of the double-ended compensating lever D, working upon a fulcrum E fixed
to the permanent way. From this arrangement it will be seen that as the
rods C, C, expand or contract through variations in the temperature of the
atmosphere, such expansion and contraction will result in the moving of the
compensating lever D to the one side or the other of the position shewn in
full lines, as indicated by the dotted lines in Figure 2, and the accuracy of the
position of the switch A or lever B will consequently not in any way be
affected by such expansion and contraction, thus rendering adjustment

page_text: unnecessary, as it will be evident that whatever position (within certain
limits not exceeded by the amount of expansion and contraction of the rods)
the lever D may be in, the motion of the lever B will always effect a corre-
sponding motion of the switch A. If the distance between the lever B and
the switch is very considerable, then instead of having only one lever D, the
rod.C, C, may be divided into three or more parts connected to two or more
such levers. Instead of forming the lever D double-ended as shewn, working
upon a fixed fulcrum E, it may consist of two separate levers fixed in opposite
positions upon a spindle working in bearings fixed to the permanent way.
Figures 3 and 4 shew respectively an elevation and a plan of an arrange-
ment in which the compensating lever D is placed in a vertical position, and
the rods C, C, provided with hinged joints c, c, to connect them with the
lever. In order to cause the rods to work by tension instead of by thrust,
whereby they can be made of less strength, counterpoises F, F¹, are connected
thereto in a similar manner, as is customary with the ordinary construction
of the connecting rods.
'
Figure 5 shews an elevation of a similar arrangement as applied to the
working of a signal G, where the rods C, C, may, as usual, be mere wires or
chains, in which case the compensating lever D is caused to move by the
counterpoises F, F¹, when the wires or chains expand, but is moved by the
latter when they contract. Instead of having two such counterpoises pulling
in different directions at opposite ends of the lever D, only one such counter-
poise of double the weight may be employed.
Having now described the nature of my Invention, and the manner in
which it is to be performed, what I claim is, constructing the rods, or their
equivalents, that serve to communicate motion to points and signals of
railways, of two or more lengths, and connecting the contiguous extremities
of such lengths to the opposite ends of one or more double-ended levers or
their equivalents, substantially and for the purposes herein-before set forth.
In witness whereof, I, the said Henry Wadkin, have hereunto set
my hand and seal, this Fourteenth day of October, in the year of
our Lord One thousand eight hundred and sixty-four.
-
HENRY WADKIN. (L.S.)