A NEW OR IMPROVED MULTIPLYING GEARING FOR TRANSMITTING AND MULTIPLYING POWER, WHICH SAID GEARING MAY BE APPLIED TO CRANES, WINDLASSES, CAPSTANS, AND PRESSES, AND TO OTHER PURPOSES WHERE IT IS REQUIRED TO TRANSMIT AND MULTIPLY POWER
Year: 1862

page_text: PROVISIONAL SPECIFICATION left by Thomas Aldridge Weston at the
Office of the Commissioners of Patents, with his Petition, on the 9th
January 1862.
I, THOMAS ALDRIDGE WESTON, of Birmingham, in the County of Warwick,
Mechanical Engineer, do hereby declare the nature of the said Invention for
'A NEW OR IMPROVED MULTIPLYING GEARING FOR TRANSMITTING AND MULTIPLYING
POWER, WHICH SAID GEARING MAY BE APPLIED TO CRANES, WINDLASSES, CAPSTANS,
AND PRESSES, AND TO OTHER PURPOSES WHERE IT IS REQUIRED TO TRANSMIT AND
MULTIPLY POWER," to be as follows:-
My said Invention consists of the following combination of parts:-To a
fixed support a hollow or annular wheel is fixed, the said wheel having teeth
on its inner cylindrical surface. Through a central opening in the said wheel
a shaft capable of a rotatory motion passes, and on the said shaft is firmly
keyed another hollow or annular wheel also having teeth on its inner cylin-
drical surface. I will call the former the fixed annular wheel, and the latter
the rotating annular wheel. The said wheels face each other and together
form a hollow cylinder or drum, having teeth on its inner cylindrical surface,
one half of the said drum being fixed and the other half being capable of a
rotatory motion. The two halves of the said drum are not of exactly the same
diameter as the teeth of one of the wheels, although the same in number as
are of a slightly different pitch from those of the other wheel. Or the teeth
may be of the same size in both wheels, and one wheel have one or more
teeth than the other. Surrounding the axis of the rotating annular wheel is a

page_text: hollow shaft, terminating at one end in the hollow drum formed by the fixed
annular wheel and the rotating annular wheel. The said hollow shaft carries
at its end external to the said drum a pulley, by which a rotatory motion can
be given to it. Upon the end of the hollow shaft within the drum is fixed an
excentric, and upon the said excentric and capable of turning upon it is a
pinion, which nearly fills the space enclosed by the two wheels. The said
pinion has teeth which gear at the same time with the internal teeth of both
the annular wheels. As the said pinion is always excentric to the annular
wheels it is always in gear with them on one side, and out of gear with them
on the opposite side.
By giving motion to the hollow shaft, whose excentric end carries the
pinion, the said pinion is made to roll round the interior of the drum formed
by the two annular wheels, the teeth of the said pinion gearing with the teeth of
the said wheels as it travels, so that in travelling round the said hollow drum
once it gears in succession with all the teeth of the said wheels, that is to say,
it is always in gear with some of the teeth of the fixed annular wheel, and also
with some of the adjacent teeth of the rotating annular wheel. As, however,
one of the said wheels has a different number of teeth from the other, or the
same number of teeth of slightly different pitch, the pinion in its rolling
motion causes the rotating annular wheel slowly to move the pinion as it
advances, bringing exactly opposite to each other teeth which were not pre-
viously in exact opposition. The rotatory motion of the hollow shaft carrying
the pinion is thus transmitted to the axle of the rotating annular wheel, which
moves with a slow motion but with increased power. The fixed wheel may be
made capable of motion at pleasure for the purpose when required of giving
rotation to the shaft of the rotating annular wheel without multiplying the
power.
Instead of driving the hollow shaft by means of a pulley, any other means
of communicating motion thereto may be employed.
In applying my Invention to screw presses I substitute the screw of the
press for the axle of the annular rotating wheel, and make the hollow screw in
the said rotating wheel.
My Invention is especially applicable to cranes, windlasses, capstans, and
presses, but is also applicable to other purposes where it is required to
transmit and multiply power.