METHODS OF APPROPRIATING CERTAIN MECHANICAL POWERS TO THE REDUCTION OF FRICTION
Year: 1791

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, JAMES
SHARPLES, of Lansdown Place, Bath, in the Parish of Walcott and County
of Somerset, Portrait Painter, sends greeting.
WHEREAS His most Excellent Majesty King George the Third did, by His
Letters Patent, bearing date at Westminster, the Twelfth day of October, in
the thirty-first year of His reign, give and grant unto me, the said James
Sharples, His special licence, full power, sole priviledge and authority, during
the term of fourteen years therein expressed, to make use of, exercise,
and vend, within that part of Great Britain called England; the Dominion
of Wales, and the Town of Berwick-upon-Tweed, my invented "METHODS
OF APPROPRIATING CERTAIN MECHANICAL POWERS TO THE REDUCTION OF FRICTION;"
in which said Letters Patent there is contained a proviso or condition' obliging
me, the said James Sharples, by an instrument in writing under my hand and
seal, particularly to describe and ascertain the nature of my said Invention',
and in what manner the same is to be performed, and to cause the same to be
enrolled in His Majesty's High Court of Chancery within one month after
the date of the said Letters Patent, as in and by the same, relation thereto
being had, will more fully and at large appear..
NOW KNOW YE, that in pursuance of and in compliance with the said
proviso or condition, I, the said James Sharples; do hereby declare that the
nature of my said Inventions, and the manner in which the same are to be
performed, are herein-after particularly described and ascertained, that is to
say:-

page_text: My new methods of appropriating certain mechanical powers to the reduc-
tion of friction on gudgeons, cranks, pivots, axles, and axletrees of every
description. These powers I call rolling or perpetual levers, Figs. 1, 2, 3, 4,
5, 6, and chain friction-wheels, Figs. 16, 16, 16, 16, 16, in the margin. These
perpetual levers consist of rollers and axles; these rollers may be either loose
or fast upon their respective axles, and there may be one or any number of
them upon each axle, and as few or as many of the rolling levers may be
applied to any side of or in any direction upwards, downward, horizontally,
or obliquely, to gudgeons, cranks, spindles, rollers, axles, axletrees, pivots, or
by whatever name or names anybody may have, which is meant to revolve
round, or in part round, its center. The ends of the axles or pivots in the
ends of the axles, as at Fig. 14, are situated in grooves, holes, or sockets, in
such a manner that their centers may be linable with each other, and the
rollers and axles must be so proportioned that the axles, as at Fig. 1, shall be
in contact with the outward extremity of the roller Fig. 2, and the axle of Fig. 2
in contact with the outward extremity of Fig. 3, and so on with any greater
number of levers in each set; and in order to keep them in this position, that
is, to bear equally upon each other, I have contrived ballances, as at B, B, B;
these ballances also support the weight impressed upon the rolling levers, but,
according to their intended uses, these ballances may be made in a great
variety of forms; those at B, B, B, form a segment of a circle at top, which
segment, resting upon a line or plane, will move till all the rollers are in con-
tact, and lineable with all the axles; but the ballance may be a straight line at
top and move upon a segment of a circle, or the box in which the rolling
levers are confined may have the end formed in such a manner as to answer
the same purpose. In fire, there are innumerable ways of ballancing them.
I do not confine it to modes of performing it, so they are made capable of
setting themselves two upon each other. The gudgeons of millwheels cannot
possibly be made or set so true as to bear equally upon a line their whole
length, and were the rolling levers fixed to them without the contrivance of a
ballance the levers and gudgeons would constantly damage each other; and
here there is one great advantage the rolling levers have over the common
friction wheels, that the bearing is upon any length of line, instead of a point;
on this account they are capable of bearing the greatest weights necessary
without indenting, and on this account are applicable to carts, waggons,
coaches, and carriages of every denomination, see Fig. 15; where one end of
the axletree is fast in the box of the wheel, the other end rests in a hole or
socket made to receive it. This axletree, or rather the arm of an axletree; lies
in an oblique direction to the framing of the carriage, in order to set the spokes

page_text: of the wheel perpendicular and to keep the carriage steady. As near the box of
the wheel as is convenient a set of rolling levers are placed over the axle, as at
4 in the Drawing. The arms of the axles do not meet each other, but if it is
thought expedient they may be made with their ends to extend beyond each
other; but it is better for the wheels to turn with an axle, or arm of an axle, of
this kind, than to extend from one box of the wheel to the other, because in
that case there are two motions that are detrimental to each other, I mean the
motion of the wheels round the axletree and the motion of the axletree
under the rolling levers; for whenever one wheel is describing a greater circle
than the other, that is, when it is turning or making the least deviation from
a straight line, the rolling levers will be at rest, because the axletree has to
force itself round in the box of that wheel that is describing the lesser circle ;
and, as a carriage cannot be drawn in a direct line for any considerable distance,
it is impossible it should receive all the advantage it is capable of unless the
wheels and axles are made independant of each other; the very motion of a
horse in trotting will in some measure lessen the effect. At the end of the
arm of the axletree a set of levers may be placed on the under side, tho
there will be little advantage gained from them, as the end may be made
conical, and to rest upon a point. The friction from this mode of placing wheels,
exclusive of the rolling levers, would be considerably reduced. Figs. 16
are my chain friction wheels, so called from the axle of one wheel resting upon
the internal rim of the other, which may be of considerable use in various
kinds of mechanism, and particularly in the rollers of cotton mills; for if a
band, as at O, was to go round the upper wheel, and a weight applied at P,
instead of the friction the rollers have upon the band, it would move the first
wheel round, the axles of which rolls on the internal rim of the second wheel O.
Now if the axle of the first wheel is a fifth part of the diameter of the wheel,
and the axle of the second a tenth part, the reduced friction would be a
fiftieth part; apply another wheel whose axle is one tenth part of the
wheel, and the friction would be only 5 part. If a rope is put over
the lower wheel at S it will serve for a pulley. T is the method of applying
the rolling levers to the inside of wheels. E is the application of a double set
of levers to shafts and axletrees. N is the mode of applying them to perpen-
dicular shafts, which will require three sets at least. By way of ascertaining
the utility of this system we will suppose the three rollers, Fig. 1, 2, 3, are an
inch and half diameter, and their axles. half an inch (which, with a short
bearing, will be strong enough for carriages made in wrought iron or steel), the
reduced friction will be 27 part, which is equal to a common friction wheel of
eighty-one inches in circumference, with an axle of one inch diameter, and the