IMPROVED MEANS FOR INCREASING THE TRACTIVE POWER OF ROAD AND OTHER LOCOMOTIVE ENGINES AND CARRIAGES
Year: 1869

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery
Lane, in the County of Middlesex, Patent Agent, for, the Invention
of "IMPROVED MEANS FOR INCREASING THE TRACTIVE POWER OF ROAD AND
OTHER LOCOMOTIVE ENGINES AND CARRIAGES."-A communication from
abroad by Eugène Bachelier, Builder, of 13, Boulevart St. Martin,
Paris.
Sealed the 13th. August 1869, and dated the 19th February 1869.
PROVISIONAL SPECIFICATION left by the said Alexander Melville
Clark at the Office of the Commissioners of Patents, with his
Petition, on the 19th February 1869.
I, ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the
County of Middlesex,. Patent Agent, do hereby declare the nature of
the said Invention for "IMPROVED MEANS FOR INCREASING THE TRACTIVE POWER
OF ROAD AND OTHER LOCOMOTIVE ENGINES AND CARRIAGES," to be as follows:-
The object of the present Invention is to secure increased adhesion
for the wheels of locomotives, traction engines, and other mechanically

page_text: propelled vehicles, so as to prevent all slip and enable them to ascend
inclines which hitherto have been impassible to such vehicles.
The improvements consist in providing series of bearing surfaces,
each attached at its centre to the periphery of the propelling wheel.
These bearing surfaces are provided with cheeks embracing the wheel
in the manner of a skid brake and forming a series of jointed surfaces,
which are presented one after the other to form a bearing surface in
a horizontal plane instead of a circle tangential to such plane, as an
ordinary wheel.
In applying the improvements to a road locomotive I provide the
hind or propelling wheels with a bearing surface composed of metal
plates with raised sides or checks embracing the periphery of the wheel.
The upper surfaces of these plates are provided with two semicircular
transverse ribs corresponding with similarly shaped recesses formed on
the periphery of the wheel. These bearing surfaces are each connected
at the centre to the periphery of the wheel by a jointed stem or bolt
projecting between the spokes. These stems are screwed at their ends
and held in position by a nut, which compresses a spring contained in
a box between the nut and the wheel, the spring having a constant. ten-
dency to keep the bearing surface up to the wheel. When the wheel
turns round each of the bearing plates are presented successively on
the ground to form a bearing surface, the ribs of said plates gearing
with the grooves on the periphery of the wheel. In this manner the
periphery forms a polygonal figure, each face of which is a plane tan-
gential to the running surface, instead of the latter being simply a
tangent as is the case with a wheel. The polygon is formed of a series
of independent parts connected to the wheel, and which may be readily
replaced when worn, as they are simply attached by a bolt, as before
described. The bearing plates follow each other in an inclined direction,
by which means any sand or other matters becoming interposed are
readily got rid of. The bearing plates have a flat surface when applied
to road locomotives, while in the case of a railway locomotive they
would be grooved to correspond to the form of the rail.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Alexander Melville Clark in the Great Seal Patent
Office on the 14th August 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Nineteenth day of February, in the year
of our Lord One thousand eight hundred and sixty-nine, in the thirty-
second year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Alexander Melville Clark, Her special
licence that I, the said Alexander Melville Clark, my executors, adminis-
trators, and assigns, or such others as I, the said Alexander Melville
Clark, my executors, administrators, 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
"IMPROVED MEANS FOR INCREASING THE TRACTIVE POWER OF ROAD AND OTHER
LOCOMOTIVE ENGINES AND CARRIAGES," a communication to me from
abroad by Eugène Bachelier, Builder, of 13, Boulevart St. Martin, Paris,
upon the condition (amongst others) that I, the said Alexander Met-
ville Clark, my exccutors or administrators, by an instrument in
writing under my, or their, or one of their hands and seals, should pa-
ticularly 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 Scal Patent Office within six calendar montlis
next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Alexander Melville Clark, 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, reference being had to the Sheet of
Drawings hereunto annexed, and to the letters and figures marked
thereon (that is to say) :-
:-
In drawing a load on a cart the feet of the person or animal bear on
the ground, while the tractive power is applied to the vehicle for the

page_text: purpose of turning the wheels; the latter transform the forward hori-
zontal movement (which would tend to slide them along the ground)
into a rolling motion, and thereby present less resistance. If it is desired
to prevent a vehicle descending an inclined plane one of the wheels is
usually fixed by a brake or chain, so as to cause it to slide instead of
turning, which augments the resistance sufficiently to counterbalance
the gravity of the load. If the incline is very steep and the downward
tendency greater a skid is generally applied, which partially embraces
the periphery of the wheel, and at same time presents a much larger
adherent surface than that of the rim of the wheel. The above, as
shown in the case of a vehicle to be drawn, applies with still more
force to vehicles used for drawing loads in which the tractive power
is proportionate to the adhesion of the traction wheels on the road or
other running surface, and as above stated the greater the bearing
surface of the wheel the greater will be the adhesion, thus utilizing to
the greatest extent the power expended.
In all vehicles operated mechanically for drawing loads with wheels
running on a flat surface there is an insufficient amount of adhesion to
enable such vehicles to ascend even the most moderate inclines, notwith-
standing that these vehicles, such as railway and road locomotives,
velocipedes, and others, are readily held stationary on inclines by the
smallest skid or brake.
The object of the present Invention is to secure increased adhesion
for the wheels of traction engines and other vehicles, so as to prevent
all slip and enable them to ascend inclines which hitherto have been
impassible to such vehicles.
The improvements consist in providing a series of flat independent
bearing surfaces, each attached at its centre to the periphery of the
traction wheel. These flat bearing surfaces are provided with cheeks
embracing the rim of the wheel in the manner of a skid brake, and form
horizontal surfaces bearing in succession upon the road, in lieu of the
circular surface of an ordinary wheel, to which the flat surfaces are
tangential.

page_text: 3rdly. I claim the right of making the bearing plates C either
smooth or corrugated on the under surface or grooved to correspond
to the form of the rails on which they may travel.
In witness whereof, I, the said Alexander Melville Clark, have
hereunto set my hand and seal, this Fourteenth day of August,
in the year of our Lord One thousand eight hundred and sixty-
nine.
Witness,
WILLIAM CLARK,
53, Chancery Lane,
London.
A. M. CLARK. (L.S.)