IMPROVEMENTS IN STEAM ROLLERS FOR ROLLING ROADS AND IN PITCH CHAINS FOR WORKING THE SAME AND FOR OTHER PURPOSES
Year: 1867

page_text: LETTERS PATENT to David Thomson, of 3, Old Street, in the County of
Middlesex, for the Invention of "IMPROVEMENTS IN STEAM ROLLERS FOR
ROLLING ROADS AND IN PITCH CHAINS FOR WORKING THE SAME AND FOR OTHER
PURPOSES."
Sealed the 15th November 1867, and dated the 20th May 1867.
PROVISIONAL SPECIFICATION left by the said David Thomson at the
Office of the Commissioners of Patents, with his Petition, on the
20th May 1867.
I, DAVID THOMSON, of 3, Old Street, in the County of Middlesex, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN STEAM
ROLLERS FOR ROLLING ROADS AND IN PITCH CHAINS FOR WORKING THE SAME AND
FOR OTHER PURPOSES," to be as follows:-
I
In constructing rollers, for rolling roads, to be propelled by steam power
form the roller in two halves lengthwise, the two halves being on the same
axle but driven separately by the steam power in such a way that either halt
can be detached and move loosely on the axle, while the other is driven by the
engine, and thus the turning of the machine on the road is made easier. I
steer, turn, or guide the machine by means of 2 wheels which work in
separate frames turning on perpendicular axes, but which are so connected by

page_text: levers, or screw wheels, or other suitable gear that the two wheels always
revolve in parallel planes, and the steerage of the machine is effected by
causing the said frames to turn to any required degree on their perpendicular
axes.
I form the framing of road rollers propelled by steam power of a box
formed of wrought-iron plates and angle irons completely enclosing the roller,
except on the under side, where it rests on the ground, so as to attain the
greatest stiffness and rigidity in the said framing, and the box is prolonged at
each side to embrace the boiler, steam machinery, and the steering apparatus
in the same rigid framework.
I form the rollers above described of wrought-iron plates and angle irons
rivetted together so as to make a complete and rigid roller, and I then add
plates of iron to the external circumference, and secure them by bolts so as
to be easily renewable when worn by contact with the road,
In making the pitch chains that have been generally used for working
road rollers and traction engines I form the said chains of cast iron,
malleable cast iron, or other cast metal, by having each alternate link cast
with an opening in the side to admit the next link, which is cast whole or
close all round, and I close the said opening by a piece of metal inserted
therein, and secured by one or more bolts or rivets. Pitch chains made in
this way are equally applicable to chain pumps, grain hoists, or other
machines which are worked with pitch chaine nessing'ozon töothing shaile
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
. by the said David Thomson in the, Great Seal Patent Office on the
20th November '1867. .
*
TO ALL TO WHOM THESE PRESENTS SHALL COME, 'I," DAVID
THOMSON, of 3, Old-Street, in the County of Middlesex, send greeting....
WHEREAS Her most Excellent Majesty, Queen Victoria, by. Her. Letters
Patent, bearing. date the Twentieth day of May, in the year of. our Lord
One thousand eight hundred and sixty-seven, in the thirtieth year of: Her
reign, did, for-Herself, Her heirs and successors, give and grant unto me, the
said David Thomson, Her special licence that I, the said, David Thomson, my
executors, administrators, and assigns, or such others as I, the said David
Thomson, my executors,.adininistrators, 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

page_text: Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN STEAM:
ROLLERS FOR ROLLING ROADS AND IN PITCH CHAINS FOR WORKING THE SAME AND
FOR OTHER PURPOSES," upon the condition (amongst others) that I, the said:
David Thomson, 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 David Thomson, do hereby declare the
nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof, that is to say:-
In constructing rollers (for rolling roads) to be propelled by steam power I
form the roller in two halves lengthwise, the two halves being on the same
axle but driven separately by the steam power in such a way that either balf
can be detached and move loosely on the axle, while the other is driven by
the engine, and thus the turning of the machine on the road is made easier.
I steer, turn, or guide the machine by means of two wheels which work in
separate frames turning on perpendicular axes, but which are so. connected by
levers or screw wheels, or other suitable gear, that the two wheels always
revolve in parallel planes, and the steerage of the machine is effected by-
causing the said frames to turn to any required degree on their perpendicular
axes.
I form the framing of road rollers propelled by steam power of a box
formed of wrought-iron plates and angle irons completely enclosing the roller,
except on the under side, where it rests on the ground, so as to attain the
greatest stiffness and rigidity in the said framing, and the box is prolonged
at each side to embrace the boiler, steam machinery, and the steering
apparatus in the same rigid framework.
I form the rollers above described of wrought-iron plates and angle irons.
rivetted together so as to make a complete and rigid roller, and I then add.
plates of iron to the external circumference, and secure them by bolts su as
to be easily renewable when worn by contact with the road.
In making the pitch chains that have been generally used for working.
road rollers and traction engines I form the said chains of cast iron,
malleable. cast iron, or other cast metal, by having each alternate link
link cast with an opening in the side to admit the next link, which is cast.
whole or. close all round, and I close the said opening by a piece of metal.

page_text: inserted therein, and secured by one or more bolts or rivets. Pitch chains
made in this way are equally applicable to chain pumps, grain hoists, or other.
machines which are worked with pitch chains passing over toothed wheels.
And in order that my said Invention may be most fully understood and
readily carried into effect, I will proceed to describe the Drawings hereunto
Figure is a side view of a steam roller constructed according to my
Invention Figure 2 is a front view, Figure 3 a back view, and Figure 4 a
longitudinal section of the same.
a, a, is a framework constructed of iron plates and angle iron; it is made
of a box-like form, and completely encloses the roller b. a' is a transverse
partition running from side to side of this frame between the roller b and the
vertical cylindrical boiler c; a' is another transverse partition near the front of
the machine; it carries upon it the principal parts of the engines by which the
machine it propelled. This partition a³ is so constructed that it can be
removed from the other parts of the frame to allow of ready access to the
roller when repairs are necessary, and with it there is combined a casing a³ to
enclose and protect the engines; a³*, a³*, are doors in this casing.
Figure 5 is a vertical section and Figure 6 a horizontal section of the
partition a and the casing a³, together with parts of the engines carried.
thereby. The steam cylinders d are mounted on the top of this portion of
the framing, and their piston rods by means of connecting rods give motion
to the crank shaft e, which has upon it two chain pinions e¹, e¹, which, by
means of the clutches and clutch levers, can be made fast or loose on the
shaft at pleasure; is a small fly wheel so weighted as to balance the parts
of the engine. The chain pinions drive the endless chains f, f, which also
encircle chain wheels b', 6', fixed upon the roller b; a vertical section of this
roller is shewn at Figure 7, and an end view of it at Figure 8. * is its axle
mounted in axle boxes, which are able to play up and down in guides in the
frame a, which is supported from them through strong springs g. The roller.
is made in two parts, each consisting of a cast-iron tubular boss bhaving
two discs of plate and angle iron 6* firmly fixed to it, and to these are rivetted
a circumference or drum 65, also of wrought-irou plates, and over these again
wearing plates of wrought iron are attached by screw boits, so that they
can be readily removed and replaced when worn out. In place of making
the roller in two parts as above described, it may be made in one, and then one
driving chain only may be used, but in some cases the making it in two parts

page_text: is convenient.
turn upon it. Oil grooves are formed within the bosses at 63* ; they are
supplied from oil cups, and the brass tubes around the axle are perforated
within these grooves, or the bosses 3 may work directly on the axle 6. One
end of the machine is carried by two steering wheels h, h; they are mounted
in forks formed at the end of the vertical spindles i, i; these are able to
slide up and down through sockets k, k, fixed to the frame, and these sockets
are connected by tie rods k³, k¹, with plates k, against which strong coiled-
springs around the spindle bear, the lower end of the springs resting upon
collars on the spindles. At the top of each spindle is a quadrant, the
teeth of which gear with worms 1, 1, on the axes of which are bevilled
wheels,, gearing with other similar wheels m¹³, m³, on the axis of which
is the hand wheel n.
The axle is clothed with tubes of brass which are able to
Figure 9 is a side view and Figure 10 a front view of one of the steering
wheels and spindle; Figure 11 is a side view of the upper end of the spindle
with the quadrant upon it; and Figure 12 is a plan of the quadrant and
driving worm. Between the vertical spindles of the steering wheels a passage
is formed to give access to the furnace of the boiler; the entrance to this
passage is by a doorway formed in the transverse partition a', which forms the
back of the frame a. n is a steam valve by which the passage of the steam
to the engines is regulated; and o is the reversing lever of the engines; p is
a water tank; and a³× is a ladder at the front of the engine for ascending to
the platform.
Figure 13 is a side view of the link of a pitch chain formed in cast metal
according to my Invention, and Figures 14 are front and sectional views of
another link with side cheeks and pins cast in one piece. In making up the
chain these two links are employed alternately; the link shewn at Figure 13
is made with an opening at the side to admit the links shewn at Figures 14,
and the opening is then closed by a filling block a, which is secured by a
screw bolt and nut; or rivet chains thus constructed are applicable to rollers
already described, and they are also applicable to driving other machinery,
and more especially they may be used for chain pumps; in this case some of
the alternate links, in place of being made as shewn at Figure 13, take the
form indicated at Figure 15, the link being made in two parts held together
with rivets and carrying the disc or bucket 6 between them.
Figure 16 shows on a smaller scale the links Figures 13, 14, and 15
combined together.
Having thus described the nature of my said Invention, and the manner of
performing the same, I would have it understood that I do not confine

page_text: myself to the exact details described; but what I claim is, the general
arrangement of a steam roller as herein-before described.
I also claim. the employment in steam rollers of two steering wheels
turning, on separate vertical spindles, as described.
I also claim forming the framing of a steam roller of a casing of plates and
angle iron so arranged as to form a stiff box-like,frame enclosing the roller
except on the under side, and also, serving to enclose the moving parts of the
machinery or some of them.
I also claim the forming pitch chains of, cast metal, the alternate links
having openings in them for the admission of the other links, as described. .
In witness whereof, I, the said David Thomson, have hereunto set my
14
hand and seal, this Twentieth day of November, in the year of our
Lord One thousand eight hundred and sixty-seven.
DAVID THOMSON. (L.S.)