IMPROVEMENTS IN ROLLING STOCK, MORE PARTICULARLY SUCH AS IS USED ON TRAMWAYS OR LIGHT RAILWAYS
Year: 1878

page_text: PROVISIONAL SPECIFICATION left by Francis William Fox, Edwin Walker,
and Edward Perrett at the Office of the Commissioners of Patents on the
23rd April 1878.
FRANCIS WILLIAM FOX and EDWIN WALKER, both of the Atlas Engine Works,
near Bristol, in the County of Gloucester, and EDWARD PERRETT, of 23, Abingdon
Street, in the City of Westminster. "IMPROVEMENTS IN ROLLING STOCK, MORE
PARTICULARLY SUCH AS IS USED ON TRAMWAYS OR LIGHT RAILWAYS."
This Invention has for its objet improvements in rolling stock, more particularly
such as is used on tramways or light railways.
Tram locomotives have hitherto been made with four wheels only; we construct
them with four wheels, forming a short rigid base, and add at one end of the engine
another pair of wheels on a swinging frame, pivotted somewhere between their axle
and the wheels at the other end of the engine, so as to form in connection with the
other wheels a long flexible wheel base. These swinging wheels may be controlled
by levers or gear, and thus the engine can be steered on or off branch lines.
When the engine has to run over dusty or muddy roads the closing of the various
moving parts from dirt and grit is a great object, particularly to the slide blocks;
and bars on which they move. We remove these blocks and bars, and carry the
end of the piston rod in a swinging lever with a closed end; this lever also receives
the end of the connecting rod. The slight oscillation of the piston rod is provided
for by the use of a trunk in the cylinder, or a short link is interposed between the
end of the rod and lever.
As the rendering of the waste steam invisible or nearly so is important, to meet
this we provide on the exhaust pipe a three-way cock, with an outlet to the chimney,
and an outlet to a water tank, so that a portion of the steam may go into the
chimney, and mixing with the hot gases may be made to disappear, and a portion
passing into the water tank may be condensed. By setting this cock the pro-
portion of exhaust steam to the chimney and tank may be varied as found
desirable.

page_text: Simplicity and power in the brake gear being important, we suspend the brake
blocks on each side of the wheel by the usual hangers, and we carry a rocking shaft
upon one of the blocks. This shaft passes across the engine or carriage from the
block on one side to the corresponding block on the other side, and being carried in
bearings on the blocks it is rocked by a lever. Near each end of this shaft is placed
a short lever, with a rod passing to the block on the other side of the wheel so
arranged that when the first-mentioned lever is moved, the distance between the
blocks is shortened, and the wheel gripped between thein.
We provide carriages with wheels that will run with equal facility upon edge or
tram rails or upon common roads.
To carry this into effect we provide a plain cylindrical or conical wheel.
The guiding flange necessary when the vehicle is running upon rails is a separate
and distinct construction, placed upon the back of the plain wheel where the ordinary
flange is placed, and capable of sliding across the back of the wheel when such
motion is necessary, so by its projection to form a flange on the plain wheel when
used on rails, or by its withdrawal to leave the surface of the plain wheel free to
roll upon the common road.
We will describe two methods by which the desired object may be obtained, one
for cases in which the axles of the carriage are fixed, and one for cases in which
the axles revolve.
When the axle is fixed, and the plain wheel revolves loosely upon the axle, we
fix upon the axle a small eccentric or similar contrivance. Upon this eccentric we
place another eccentric, controlled and held in position by a lever or other means;
this outer eccentric is so formed that when in one position its circumference is
eccentric to the fixed axle, and when placed in another position its eccentricity
neutralizes the eccentricity of the inner eccentric, and the exterior surface of the
outer eccentric becomes concentric with axle.
The flange, which may be a plate or ring in one or more parts, with suitable
arms, is connected to the wheel by bolts in slotted holes by V grooves or other
contrivances, so that whilst firmly fixed to the wheel, so far as lateral movement is
concerned, the disc is capable of a sliding movement across the wheel when necessary.
The disc is of rather larger diameter than the body of the wheel, and projects beyond
it so as to form a flange, and the disc is bored out to receive the outer eccentric
previously described.
When running upon rails, the eccentrics being placed in opposition, and thus
neutralizing each other, the wheel and disc move round together with equal angular
motion. When the eccentrics are placed in conjunction the flange or disc projects
beyond the wheel only on the upper side, leaving the plain body of the wheel to
run upon the road. This placing of the eccentrics in conjunction or opposition
may be effected by moving the exterior eccentric by a lever, rack, or other means,
or it may be effected by turning the axle itself, on which the inner eccentric is
fixed.
When the axle revolves the inner eccentric is bored out, and is loose upon the
axle, but it is prevented from turning round with the axle by a stop or lever fixed
to the axle box or any other stationary part of the vehicle, and the action is then.
as described for the fixed axle, i.e., by moving the outer eccentric so as to bring it
eccentric or concentric with the axle, and thus control the flange.
In vehicles fitted with the previously mentioned wheels we place one of the two.
axles ou a swinging or locking frame, like an ordinary road waggon, and provide,
it with moveable horse traction gear, so that when it is desired to take the vehicle
off the rails or tram the flanges of the wheels are moved as before described, and the
carriage being fitted with the locking frame is capable of being drawn over common
. roads, and round sharp curves like an ordinary four-wheeled road vehicle.
When on the rails the swinging or locking frame may be fixed to the body of
the carriage, so as to form a rigid wheel base, as is usual in four-wheeled carriages
running on rails or trams.

page_text: For rolling stock, such as railway carriages or truck or tram cars that require
six wheels to support them and distribute the weight, but yet require to be capable
of passing easily from straight. lines to and round sharp curves, we place a pair
of wheels upon an axle in fixed axle boxes or guides near the centre of the
carriage.
Towards each end of the carriage we place a pair of wheels on an axle carried in
a swinging frame pivotted towards the centre of the carriage, and we apply the
hauling power to the swinging frame. In this manner semi-rigid connection is
made between the front and centre pair of wheels capable of easily taking a curve,
whilst the back pair of wheels are enabled to take any position that may be required
for easy passage over or on to curves.