IMPROVEMENTS IN TRACTION ENGINES
Year: 1876

page_text: LETTERS PATENT to John Coulson, of Stamford, in the County of Lincoln,
Engineer, for the Invention of "IMPROVEMENTS IN TRACTION ENGINES."
PROVISIONAL SPECIFICATION left by the said John Coulson at the Office of
the Commissioners of Patents on the 8th July 1876.
JOHN COULSON, of Stamford, in the County of Lincoln, Engineer. " IMPROVE-
MENTS IN TRACTION ENGINES."
The object of this Invention is to give direct action to the driving gear of traction
engines from the crank or main shaft.
On each end of the ordinary crank shaft I place a toothed pinion, which latter
is caused to rotate with the former by means of a feather, but the pinion is capable
of being moved longitudinally with the axis of the shaft so as to gear either with
the larger internal toothed ring on the periphery of the traction wheel, or to gear
with a smaller toothed ring attached to the arms of the wheel, according as it is
desired to travel at a lesser or greater rate of speed. In changing from one rate of
speed to the other the rotary action of the crank shaft is reversed to suit the
reverse action of the gearing. The toothed pinions before mentioned are caused to
rotate with the shaft by means of the feathers before mentioned, but which pinions
are capable of being moved longitudinally in the direction of the axis of the crank
shaft, and this can be brought into gear with the said larger internal toothed rings
on the periphery of the traction wheels or into gear with the lesser toothed rings
attached to the arms of the said traction wheels, according as it is desired that the
traction engine shall travel at the one rate of speed or the other rate of speed. The
axle of the traction wheels is fixed in bosses, but the traction wheels are free to
rotate on it; a bracket or support for carrying the axle is attached to one end of
the boiler, but its position may be varied to suit the circumstance of different kinds
of traction engines.
When it is preferred to drive by gearing on one side only, that is, attached to
one traction wheel only, the traction wheels are then keyed fast to the axle, and
this axle is permitted to revolve in the bosses of the said support or bracket, by
which arrangement the rotation of the one traction wheel with the gearing is
communicated to the other traction wheel.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Coulson in; the Great Seal Patent Office on the Sth January
1877.
JOHN COULSON, of Stamford, in the County of Lincoln, Engineer.
MENTS IN TRACTION ENGINES."
"IMPROVE-
The object of this Invention is to give direct action to the driving gear of traction
engines from the crank or main shaft.
Firstly. I place a toothed pinion on one end of the crank shaft, the said pinion
slides longitudinally on the former, and is made with one or more solid keys so as
not to weaken the said pinion, as it is required to be as small in diameter as strength
will allow so as to obtain proper speed to the engine.
Secondly. I place an internal toothed ring inside the tyre of the travelling wheel,
also an external toothed ring bolted on arms of the travelling wheel, and the external
toothed ring is smaller in diameter than the internal toothed ring so as to allow the
pinion on the crank shaft to slide between the two toothed rings, the two said rings
is out of line with each other so as to allow the pinion to gear in each separately,
and the crank shaft has to be long enough to go under the tyre of the travelling
wheel so as to allow the pinion to slide out of one toothed ring into the other
toothed ring, or if preferred I apply a flange on pinion, and when changed from one
speed to the other I slide the pinion out of internal gear and put another flanged
pinion on outer end of crank shaft so as only one pinion is in gear; this is if
required to give strength to the pinion by having a flange. When the pinion is
driving in the internal toothed ring it is on the top side and is slow speed, and
when driving in the smaller external toothed ring it is on the bottom side and is
quick speed; by this application with one pinion on main shaft driving direct into
the travelling wheel I obtain two speeds with one single pinion; the travelling
wheels has to be large enough to rotate over the crank shaft with the pinion on it,
the pitch of the cogs or teeth for pinion and the toothed rings must be all alike.
And in order that my said Invention may be properly understood reference is
made to the annexed Drawing.
Fig. 1 is an end view of a traction engine with the improved arrangement of
gearing attached; one traction wheel is shewn in the Drawing in section, and the
other traction wheel in elevation.
Fig. 2 is a side view of the said arrangement of gearing and that portion of traction
engine to which it is attached.
A is the boiler of traction engine. B, B, are the bearing standards for the crank
shaft C, and D, D, are the toothed pinions which are caused to rotate with the
shaft C by means of the feathers E, E, but which pinions D, D, are capable of being
moved longitudinally in the direction of the axis of the crank shaft C, and this can
be brought into gear with the larger tooth rings F, F, on the periphery of the
traction wheels G, G, or into gear with with the lesser toothed rings H, H, attached
to the arms of the said wheels G, G, according as it is desired that the traction engine
shall travel at the one rate of speed or the other rate of speed. I is a bracket or
support for carrying the axle J of the traction wheels. This axle is fixed in the
bosses K, K, of the bracket I, but the traction wheels G, G, are free to rotate on it.
The bracket I is in this case shewn attached to one end of the boiler A, but its
position may be varied to suit the circumstances of different kinds of traction
engines. When it is preferred to drive by gearing on one side only, that is, attached
to one traction wheel only, the traction wheels G, G, are then keyed fast to the
axle J, and this axle is permitted to revolve in the bosses K, K, of the support or
bracket I, by which arrangement the rotation of the one traction wheel with the
gearing is communicated to the other traction wheel.
Having thus described the nature and object of my said Invention, I wish it to
understood that I do not claim the toothed rings as new, save only as they are
applied in the manner herein-before described, but that what I do claim and desire

page_text: to be secured to me by the herein-before in part recited Letters Patent is, the
general arrangement and combination of parts whereby direct action is given to
the driving gear of traction engines from the crank or main shaft at one or both
ends without any intermediate shaft or motion, by means of the movable or sliding
pinions D, D, substantially as herein-before described and shewn on the Drawings,
or any mere modification thereof.
In witness whereof, I, the said John Coulson, have hereunto set my hand
and seal, this Sixth day of January, in the year of our Lord One thousand
eight hundred and seventy-seven.
JOHN COULSON. (L.S.)