IMPROVEMENTS IN STREET RAILWAYS AND RAILWAYS ON COMMON ROADS AND IN LOCOMOTIVE ENGINES AND CARRIAGES FOR THE SAID RAILWAYS
Year: 1861

page_text: PROVISIONAL SPECIFICATION left; by John Arrowsmith at the Office:
of the Commissioners of Patents, with his Petition, on the 18th
March 1861.
I, JOHN ARROWSMITH, of Bilston, in the County of Stafford, Engineer,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN STREET
RAILWAYS AND RAILWAYS ON COMMON ROADS AND IN LOCOMOTIVE ENGINES AND
CARRIAGES FOR THE SAID RAILWAYS," to be as follows:-
My improvements in railways for streets and common roads consist in
attaching a rack to the side of one or both rails; or fixing a rack midway
between the rails; the rack in either case extending either the whole
length of the line of railway or only along those parts where there are inclines.
The use of the said racks is to prevent the slipping of the wheels of the loco-
imotive engine as herein-after explained.
My improvements in locomotive engines for street or road railways are as fol-
lows:-I place the engine under the longitudinal seats of the first carriage, the
cylinders being by preference about six inches in diameter and with a stroke-of
about two feet. The connecting rods are attached to a double-cranked shaft,
on the outer ends of which I fix a friction disc working into grooves turned
in the internal surface of the driving wheels;. I prefer to make the driving.
wheels six feet in diameter, and on the inner face of each driving wheel and
near its periphery I fix an annular plate having teeth all round: it, which
said teeth take into the teeth of the racks on the rails. Or I fix a toothed
disc in the middle of the crank shaft, the teeth of which take into those of the

page_text: rack fixed midway between the rails. Or the toothed disc may be fixed in
the middle of the driving wheel axle and engage with the rack between the
rails. By either of the means last described the slipping of the wheels is
prevented and the whole speed of the circumference of the wheels made
available for the motion of the train. Or I place the cylinders of the engine
on the outsides of the carriages and make them work on to crank pins fixed
in the driving wheels. In this case I have two connecting rods to each
cylinder, one attached to the driving wheels, the axle of which works through
fixed bushes, the other attached to the trailing wheels, the axles of which
work through moveable bushes to allow for the varying lengths of the con-
necting rods arising from wear, or the cylinders may each have a long slide
working on its side, the said slide being secured to the piston through a slot
in the cylinder. The steam is prevented from escaping at the said slot by
means of metallic packing. I use the steam of high pressure cutting off
so as to expand it at the end of the stroke to the pressure of the atmosphere,
thus preventing noise from the escape of the exhaust steam. I make the
boilers tubular and of small diameter, and either fix them under the seats of
the second carriage, or under the first carriage between the engines, the said
boilers being felted to prevent radiation. Between the boilers I place the
funnel horizontally and create a draught in the said funnel by means of a small
fan driven from the axle of one pair of the wheels by friction pulleys or
other means..
.
.
To obviate the difficulty arising in passing sharp curves from the outer
wheels having to run at, a greater speed than the inner ones the axles may
be made in two parts jointed in the middle by a steel coupling box having
collars turned inside. By these means each of the two wheels may run at any
speed irrespective of the speed of the other.
I work the brakes so as to make them act on the rails instead of the wheels
thus obtaining greater power with less wear on the wheels and rails; I make
the engines of steel, as far as practicable, so as to ensure strength with lightness,
and I also make the framing and bodies of the carriages as far as practicable
of steel plates, stiffened where necessary with angle and bar steel. My several
improvements may either be used combined or separately.