IMPROVEMENTS IN RAILWAY SWITCHES
Year: 1866

page_text: PROVISIONAL SPECIFICATION left by John Henry Johnson at the
Office of the Commissioners of Patents, with his Petition, on the
28th September 1866.-A communication from abroad by Benjamin
Shiverick and Thomas Luther Calkins, both of Philadelphia, Pennsylvania,
in the United States of America.
I, JOHN HENRY, JOHNSON, of, 47, Lincoln's Inn Fields, in the County, of
Middlesex, Gentleman, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN RAILWAY SWITCHES," a communication to me from abroad
by Benjamin Shiverick and Thomas Luther Calkins, both of Philadelphia,
Pennsylvania, in the United States of America, to be as follows:-
This Invention consists of a peculiar arrangement and combination of
switch and frog rails in respect to the permanent rails of the main track of a
railway and to those of a turn out or siding so that the carriages may traverse
freely along the main track or be directed from the latter to the turn out, or
from the turn out to the main track; also in connecting together the switch
rails and frog rails so that they may be operated simultaneously; also in
rendering the switch rails and frog rails self-moving, so as to leave the main
track uninterrupted after a further use of the siding is unnecessary. The
switch rails are hinged at one end to the track, so that the opposite ends may
be moved to coincide with the permanent rails of the main track, or moved

page_text: to coincide with the permanent rails of the turn out or siding. Two frog
rails are employed, the one being hinged to the track adjacent to the permanent
rail of the turn out, and the latter hinged near the same point to the adjacent
rail of the main track. These frog rails are connected together, and can be
moved to and fro simultaneously to a position for opening either the main line
or the turn out. It is important that the switch and frog rails should be
operated simultaneously, this I effect in the present instance as follows:-The
two switch rails are connected by a rod to one arm of a bell-crank lever, the
outer arm of which is connected by a rod to one arm of an ordinary horizontal
lever, the other arm of the latter being connected by a rod to one arm of a bell-
crank lever, and the other arm of this lever is connected by a rod to the switch
rails. The ordinary lever is secured to a vertical shaft which is arranged to
turn in a suitable standard and which is provided with a hand wheel, so that on
turning the latter the desired movements to the two positions described may
be imparted to the switch and frog rails simultaneously. It is also important
that after the switch and frog rails have been moved in order to permit the
carriages to pass from the main track to the turn out, or vice versa, and after
further use of the turn out is not required, the said switch rails and frog
rails should of themselves move back, so that the travel on the main track
may not be interrupted, and so that no accident may occur. In order that
this may be effectually accomplished it is proposed to make the standard in
the form of a hollow column, and to surround the vertical shaft with a strong
spiral spring (or a weight and lever may be used), one end of which spring is
secured to the column and the other to the shaft, the spring being such that
it will, through the medium of the rods and levers described, restore the switch
and frog rails to their proper positions.