IMPROVE- MENTS IN LOCOMOTIVE AND TRACTION ENGINES
Year: 1871

page_text: LETTERS PATENT to Loftus Perkins, of Seaford Street, Gray's Inn
Road, in the County of Middlesex, for the Invention of "IMPROVE-
MENTS IN LOCOMOTIVE AND TRACTION ENGINES.”
PROVISIONAL SPECIFICATION left by the said Loftus Perkins at the
Office of the Commissioners of Patents, with his Petition, on the
21st October 1871.
I, LOFTUS PERKINS, of Seaford Street, Gray's Inn Road, in the
5 County of Middlesex, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN LOCOMOTIVE AND TRACTION ENGINES," to be
as follows: -
In constructing a traction engine according to my Invention I
support it on one broad central wheel which forms the driving wheel.
The boiler with the steam engine and driving gear for giving motion to
the wheel are mounted so that their weight is balanced around the
wheel, and so that they can all be revolved together within a ring frame

page_text: which encircles them. This ring is provided with arms
or shafts
standing out from it, by which it can be connected to the shafts or
other part of any vehicle the traction engine is required to draw. The
steering or guiding of the engine is effected by turning it in the ring
which encircles it, and this may be effected by a worm and worm wheel,
or by other arrangement of gearing.
In place of employing a single central wheel two wheels placed side
by side and near to one another might be employed, or two wheels of
small diameter might be placed one behind the other and be both
embraced by an endless band or chain. The band may be of vulcanized
india-rubber or of other flexible material, or a metal chain may be used
and either bear directly on the ground or be provided with flat bearing
surfaces. With this arrangement both of the wheels would be driven
by a pinion gearing into toothed wheels on the axes of the wheels. By
thus employing a band of vulcanized india-rubber a large extent of
bearing surface is obtained, whilst at the same time a far less quantity
of vulcanized india-rubber is required than when employing wheels of
large diameter furnished with thick tyres of this material.
In place of the boiler, steam engine, and driving wheel being capable
of turning within a horizontal ring they may be mounted to turn on a
central pivot, but not I believe so advantageously.
In a similar manner to that above described traction engines with
more than one driving wheel may be constructed, so that each driving
wheel with its driving gear, steam engine, and boiler may be capable of
turning in a horizontal ring on the framing of the machine, or a driving
wheel so mounted and driven may be at one end of a carriage or frame,
whilst the opposite end is simply supported on bearing wheels.
Double locomotives having a bogic frame at each end may also be
constructed in a similar manner, each bogie frame being capable of
turning in a horizontal ring and each carrying a boiler and steam engine
for driving the wheels of the bogic frame.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Fatent,
filed by the said Loftus Perkins in the Great Seal Patent Office on
the 20th April 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, Loftus
PERKINS, of Scaford Street, Gray's Inn Road, in the County of
Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-first day of October, in the
year of our Lord One thousand eight hundred and seventy-onc, in the
thirty-fifth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Loftus Perkins, Her special license
that I, the said Loftus Perkins, my executors, administrators, and assigns,
or such others as I, the said Loftus Perkins, my exccutors, adminis-
trators, 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 LOCOMOTIVE
AND TRACTION ENGINES," upon the condition (amongst others) that I, the
said Loftus Perkins, my executors or administrators, by an instrument
in writing under my, or their, or one of their hands and scals, 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 Loftus Perkins, do hereby declare the
nature of the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say:-
In constructing a locomotive or traction engine according to my
Invention, I support it on one broad central wheel which forms the.
driving wheel. The boiler with the steam engine and driving gear for
giving motion to the wheel are mounted so that their weight is balanced-
around the wheel, and so that they can all be revolved together within a
ring frame which encircles them. This ring is provided with arms or

page_text: shafts standing out from it by which it can be connected to the shafts or
other part of any vehicle the traction engine is required to draw. The
steering or guiding of the engine is effected by turning it in the ring
which encircles it, and this may be effected by a worm and worm wheel,
or by other arrangement of gearing.
In place of employing a single central wheel, two wheels placed side
by side and near to one another might be employed, or two wheels of
small diameter might be placed one behind the other and be both
embraced by an endless band or chain; the band may be of vulcanised
india-rubber or of other flexible material, or a metal chain may be used,
and either bear directly on the ground or be provided with flat bearing
surfaces. With this arrangement both of the wheels would be driven
by a pinion gearing into toothed wheels on the axes of the wheels. By
thus employing a band of vulcanized india-rubber a large extent of
bearing surface is obtained, whilst at the same time a far less quantity:
of vulcanized india-rubber is required than when employing wheels
of large diameter furnished with thick tyres of this material.
In place of the boiler, steam engine, and driving wheel being capable
of turning within a horizontal ring, they may be mounted to turn on a
central pivot, but not I believe so advantageously.
In a similar manner to that above described locomotive or traction
engines with more than one driving wheel may be constructed so that
cach driving wheel with its driving gear, steam engine, and boiler, may
be capable of turning in a horizontal ring on the framing of the machine.
Or a driving wheel so mounted and driven may be at one end of a
carriage or frame whilst the opposite end is simply supported on bearing
wheels.
In the Drawings hereunto annexed, 'I have shewn two examples of
locomotive or traction engines constructed according to my Invention.
In the traction or locomotive engine shewn in vertical section at a
Figure 1, the ring frame herein-before mentioned is provided with short
shafts or arms standing out from it by which it can be connected to
the shafts or other part of any vehicle the traction or locomotive engine
may be required to draw, and the boiler, steam engine, and condenser
are all mounted on the circular frame that is capable of being revolved
within the ring.

page_text: In the traction or locomotive engine shewn at Figures 2, 3, and 4, the
condenser is not carried on the circular revolving frame, but is placed at
one end of a carriage frame, whilst the circular revolving frame mounted
on a central wheel, and carrying the boiler, steam engine, and driving
gear, is at the opposite end of such frame. The end of the carriage.
frame at which the condenser is carried, is supported on a pair of
bearing wheels, one at each side.
I will now give a general description of the arrangement shewn at
Figure 1.
a is a circular framework which is mounted on a single broad wheel
b, surrounded by an elastic tyre as shewn. The frame a carries a tubular
boiler c, and steam engine for driving the wheel b, it also carries a
tubular condenser d, such as is described in the Specification of a former
Patent granted to me. The wheel is driven from the crank shaft e of
the engine by a pinion on the crank shaft gearing into an internal ring
of teeth around the interior of the wheel. The cylinders and other
parts of this engine are not shewn in the Drawing. I prefer to use an
inverted and compound engine, mounted at one side of the boiler, and
working downwards on to the crank shaft; but other constructions of
engine may be used. 9 is a ring embracing the circular framework a;
on the ring are shafts /, by which it can be attached to the shaft or
other part of any wagon or vehicle which it may have to draw. Around
the periphery of the circular framework a is a ring of teeth 1, into which
gears a screw or worm m, having on its axis a hand wheel o, so that by
turning this hand wheel the circular frame can be revolved within
the ring, and thus the traction engine can be steered in any desired
direction.
I would state that I do not confine myself to any special construction'
of boiler, steam engine, or condenser, but these parts, and the arrange-
ment of gearing for giving motion to the driving wheel, may be greatly
varied so long as the steam engine, boiler, and gearing are mounted
on a circular frame capable of being caused to turn within a ring as
above described.
I will now describe the construction of engine shewn at Figures 2, 3,
and 4. In this arrangement, the circular [frame only carries the boiler,
steam engine, and driving gear, and it is mounted at one end of a
carriage frame, the opposite end of which carries the condenser.

page_text: Figure 2 is a side view, Figure 3 a transverse vertical section, and
Figure 4a front view of the engine.
a is the circular frame mounted on one broad wheel b, which has an
clastic tyre around it, protected by a chain of metal links as shewn;
other forms of clastic tyre might however be used; c is a steam boiler
constructed in the manner described in the Specification of a former
Patent granted to me, No. 1822, in the year One thousand eight
hundred and seventy-one. The wheel bis driven as shewn at
Figure 3 by two separate compound engines mounted on opposite
sides of the boiler. The crank shaft d of each engine has upon it
a pinion gearing into an internal ring of teeth at the side of the
wheel. The ring of teeth at one sido can be disconnected from the
wheel, so that the engine on that side can be employed for pumping
water into the boiler, whilst the traction engine or locomotive is
standing. In each of the engines the down stroke is made by high-
pressure steam admitted at the top of the smaller cylinder, and by the
expansion of steam (previously exhausted from the small cylinder) into
the annular space above the piston of the low-pressure cylinder, whilst
the up stroke is made by the expansion of steam on the under side of
this piston, but as before stated any desired construction of engine may
be adopted, and I do not limit myself to the construction of engine
shown in the Drawing. e is a tubular surface condenser carried at the
back of the frame of the locomotive or traction engine; the exhaust
steam from the low-pressure cylinders passes by the pipe first into a
hollow roof of thin sheet metal, and from there to the tubular con-
denser. On the pipe f is a swivel joint g, which is situated on the
vertical central line of the frame a and boiler to allow of this frame
being turned for the purpose of steering. The feed water pipe / is
similarly provided with a swivel joint, but as this joint cannot (on
account of the wheel) be on the central vertical line of the frame a, the
feed water pipe is also provided with a telescopic joint as shown at
Figure 2. On the exhaust pipe from cach cylinder is a three-way cock,
by which the exhaust can at any time be shut off from the condenser
and introduced into the chimney as a blast.
The steering gear by which the circular frame a can be turned within
the ring which embraces it, is shewn at Figures 2 and 4.
k is the steering handle having on its axis a bevil wheel gearing into
a wheel on the vertical shaft, which at its lower end drives a hori-

page_text: zontal shaft m, upon which is a pinion gearing into the teeth of a
circular rack on the under side of the frame a; this circular rack need not
be carried entirely around the frame, but.only around so much of it as
is necessary to obtain the requisite amount of steerage.
Having thus described the nature of my Invention, and the manner
of performing the same, I would have it understood that what I
claim is,―
1. The construction of traction or locomotive engines with the boiler,
steam engine, and driving gear all mounted on a circular frame
supported on a wheel or wheels, and which can be revolved within a
horizontal ring, as herein described.
2. The construction of traction or locomotive engines substantially as
herein described and shewn at Figure 1.
3. The construction of traction or locomotive engines substantially as
herein described and shewn at Figures 2, 3, and 4.
In witness whereof, I, the said Loftus Perkins, have hereunto set
my hand and seal, this Twentieth day of April, in the year of our
Lord One thousand eight hundred and seventy-two.
LOTTIS
DEDIN
LOFTUS PERKINS. (L.S.)