IMPROVEMENTS IN LOOSE PULLEYS TO RECEIVE DRIVING BELTS
Year: 1879

page_text: LETTERS PATENT to Jonas Davis, of Laurence Hill, near Bristol, in the County
of Gloucester, for the Invention of "IMPROVEMENTS IN LOOSE PULLEYS TO
RECEIVE DRIVING BELTS."
Sealed the 25th November 1879, and dated the 30th May 1879.
Sealed the 25th November 1879, and dated the 30th May 1879.
PROVISIONAL SPECIFICATION left by the said Jonas Davis at the Office
of the Commissioners of Patents on the 30th May 1879.
JONAS DAVIS, of Laurence Hill, near Bristol, in the County of Gloucester.
"IMPROVEMENTS IN LOOSE PULLEYS TO RECEIVE DRIVING BELTS."
This Invention has for its object improvements in loose pulleys to receive driving
belts.
When loose pulleys of the ordinary construction are driven at high velocity there
is great difficulty in keeping them efficiently lubricated, as the oil is liable to be
thrown off by centrifugal action.
By my Invention I so contrive that the centrifugal action tends to bring the oil
to the rubbing parts, and to prevent its escape from the boss of the pulley.
For this purpose the boss is bored for nearly the whole of its length, say, one inch
larger than the shaft or spindle on which it revolves. The remaining part is bored.
slightly larger than the shaft. Into the recess thus made is fitted a loose bush of
cast iron, steel, or gun metal, having fluted ends and bored to fit the shaft, on to
which it is driven tightly. Upon the outside of the boss at its open end is screwed
a cap, bored slightly larger than the shaft. Between the cap and boss face is a sheet
lead washer. The pulley is provided with an oil feed pipe, into which a counter
sunk screw (having a leather washer) is fitted.
It will be understood that oil having been put into the boss through the pipe,
and the counter sunk screw with leather washer being screwed tightly into its place,
when the pulley is set in motion the centrifugal action tends to keep the oil on the
surfaces of the bush and between it and the interior of the boss of the pulley, and
the oil is not thrown off (as in ordinary pulleys), but is retained in the recess of the
boss, the enclosed ends of which effectually prevent the oil from escaping from off
the face of the bush on which the pulley revolves.

page_text: filled with a plug. The plug is removed for oiling, and when it is replaced a
leather or other washer is inserted beneath the head of the plug to ensure an oil
tight joint. The arrangement at f is similar, but their being room within the
periphery of the pulley, the oil tube is not continued up through it. It will be
observed that cavities are formed within the boss cat the ends of the bush or
enlargement b, in which a certain amount of oil will be retained.
Having thus described the nature of my said Invention, and the manner of
performing the same, I would have it understood that I claim, the construction
of loose pulleys revolving upon a bush or enlargement fixed upon the shaft, such
bush or enlargement being enclosed within the boss of the pulley in such manner
that the oil is retained and directed between the frictional surfaces, substantially
as described.
In witness whereof, I, the said Jonas Davis, have hereunto set my hand and
seal, this Twenty sixth day of November, in the year of our Lord One
thousand eight hundred and seventy nine.
JONAS DAVIS. (L.S.)