A NEW OR IMPROVED PULLEY
Year: 1859

page_text: LETTERS PATENT to Thomas Aldridge Weston, of King's Norton, in the
County of Worcester, Accountant, for the Invention of "A NEW OR
IMPROVED PULLEY."
Sealed the 12th August 1859, and dated the 25th April 1859.
PROVISIONAL SPECIFICATION left by the said Thomas Aldridge Weston
at the Office of the Commissioners of Patents, with his Petition, on
the 25th April 1859.
I, THOMAS ALDRIDGE WESTON, of King's Norton, in the County of Wor-
cester, Accountant, do hereby declare the nature of the said Invention for
"A NEW OR IMPROVED PULLEY," to be as follows:-
My Invention consists of a pulley for raising weights, actuating presses, and
for other like purposes, which said pulley is constructed in the following
manner-Upon the same axis two single pullies of different diameters are
situated, which said two pullies may be cast or otherwise made in one piece.
An endless chain or a chain band is passed over the said pullies in the
manner herein-after described, the said endless chain hanging down in two
loops, and a single pulley of the ordinary kind being placed in each of the
said loops. The said endless chain is passed over the first-mentioned pullies
in the following manner, that is to say, the chain, after passing over the
larger pulley, descends to any desired distance, and then rises, forming a loop.

page_text: The rising chain ascends on the side of the smaller pulley opposite to that
side of the larger one on which it descended. After passing over the smaller
pulley the chain hangs in a second loop, and again rising passes to the larger
pulley. As the axis on which the double pulley is fixed performs a rotatory
motion, the amount of chain passing over the larger pulley is greater than that
passing over the smaller pulley at each revolution, and one of the hanging
loops consequently rises and the other loop falls. The single pullies hanging
in the said loops rise and fall with the said loops. The action is a differential
one, and the rates of motion of the loops and single pullies relative to the
rotation of the axis of the double pulley is determined by the difference in the
diameters of the two pullies constituting the said double pulley. The said
double pulley is provided with teeth or other contrivance with which the
chain engages as it passes over the said double pulley. Although for con-
venience of description, I have described my Invention as carried into effect by
the use of two pullies of different diameters fixed on the same axis, and two
loops hanging from the said pullies, yet three or other number of the said
pullies and loops may be employed.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Thomas Aldridge Weston in the Great Seal Patent Office on
the 22nd October 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
ALDRIDGE WESTON, of King's Norton, in the County of Worcester, Accountant,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-fifth day of April, in the year of our Lord
One thousand eight hundred and fifty-nine, in the twenty-second year
of Her reign, did, for Herself, Her heirs and successors, give and grant
unto me, the said Thomas Aldridge Weston, Her special licence that I, the
said Thomas Aldridge Weston, my executors, administrators, and assigns, or
such others as I, the said Thomas Aldridge Weston, my executors, adminis-
trators, and assigns, should at any time agrée 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 "A NEW OR IMPROVED PULLEY," upon the condition (amongst
others) that I, the said Thomas Aldridge Weston, my executors or adminis-

page_text: trators, by an instrument in writing under my, or their, or one of their hands and
seals, should particularly 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 Seal Patent Office within six calendar
months next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Thomas Aldridge Weston, 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 thereof, that is to say :-
My Invention consists of a new or improved pulley for raising weights,
moving heavy bodies, actuating presses, and for other like purposes. My said
new or improved pulley is constructed in the manner herein-after described,
and illustrated in the accompanying Drawing.
In order that my Invention may be the better understood, I will first
describe the general nature of its construction, and afterwards describe the
methods of carrying my Invention into effect which I have found to answer
best in practice. An endless chain is so applied to an axle of two different
diameters, in the two parts to which the chain is applied, or to two pullies of
different diameters, that two depending loops are formed by the said endless
chain, each of the said loops hanging from one side of one part of the axle, or
one pulley to the opposite side of the other part of the said axle or the other
pulley. When pulleys are used the said pulleys are made to rotate together
by being fixed together or fixed to the same axis, the axis in this case rotating.
with the pulleys.
The mode of applying the endless chain is represented in Figure 1 of the ac-
companying Drawing. The two pullies are marked a and b, commencing at the
larger pulley a; the course of the chain is as follows:-The said chain descends
from the nearest side of the said pulley a, and forming the loop c, ascends to
the distant side of the smaller pulley b. Passing over the said smaller pulley b,
the chain descends, and forming the loop d, ascends to the distant side of the
pulley a to the point from which its course was commenced to be traced. If
the pulleys a, b, be rotated together in the direction indicated by the arrows,
each rotation will take from the loop c a length equal to the circumference of
the pulley a, while the said rotation adds to the loop ca length equal to the
circumference of the smaller pulley b. The loop c is thus shortened, and at the
same time the loop d is equally lengthened, the said loop & receiving at each
rotation a length equal to the circumference of the pulley a, and having taken
from it a length equal to the circumference of the smaller pulley b. By

page_text: changing the direction of the rotation of the pulleys, a contrary effect is
produced upon the loops c and d. Ordinary pulleys are placed in the loops c
and d, as herein-after explained. Three or more pulleys of different diameters
may be placed upon the axis 'e, any two of which may be used in the manner
lescribed, and a variety of speeds thus obtained. The peripheries of the
pullies a, b, are so shaped as to receive and engage with the links of the chain,
as herein-after described, and illustrated in the Drawings.
Figure 2 represents in front elevation, and Figure 3 in side elevation, a
pulley constructed according to my Invention. The two differential pulleys a
and 2 are in one piece or in parts, secured together and fitted to rotate on the
fixed axis c². The endless chain is applied in the following manner :—
Beginning on the larger pulley a², on the nearest side, the said chain descends
to the block d², passing round it, ascends to the distant side of the smaller
pulley b², passing over which it descends on the nearest side, forming a loop e²,
and returning upwards to the distant side of the larger pulley a², and over the
same to the point of starting. Motion is communicated to the pulley by
pulling the chain at any part, although when the pulley is used for lifting it is
most convenient to pull that side e' of the slack loop e² which hangs from the
larger pulley a², and the pulleys a² and 63 having spaces for twenty and
eighteen links respectively, such motion gives a power of twenty to one over
any weight or resistance at the block d. Upon the pin or rivet f, fixed in the
frame of the pulley, is a roller g, of two different diameters, leaving equal
spaces between itself and the pulleys a² and 62 at those parts opposite the said
pulleys, and at such a distance from them that the chain can only pass when
the links are in the places formed to receive them. This device prevents the
weight falling from the chain getting out of gear with the pulleys, and also
forces back any link which may have begun to rise from its place in the
periphery of either pulley. The snatch block de may be placed in either loop,
or a snatch block may be placed in each loop if required.. h, h, are bits
projecting from the peripheries of the pulleys a² and 62, against which bits
those links lying flatwise catch, the links which go on the pulleys edgewise
being received into a groove formed all round the pulleys, as shewn in the
Drawing. The power may be varied by increasing or diminishing the
difference in the circumference of the pulleys a and 62. Any convenient
method of gearing the chain to the pulleys may be adopted to suit the kind of
chain used. The plan described and represented answers well for ordinary
chain.
Figure 4 represents in front elevation, and Figure 5 in side elevation, my

page_text: new or improved pulley arranged as a lifting jack, the chain being applied as
described with reference to Figures 2 and 3. The two differential pullies a³
and having spaces for twenty and eighteen links respectively formed on
their peripheries are secured to the axis c². The wheel of the snatch block
d³ is also formed to engage or gear with the chain. Any other proportions
than eighteen and twenty links may be used in making the pullies b³ and a³.
The axis c has its end c' prolonged and formed to be rotated by a ratchet
lever or winch, or by any other convenient method. The end of the axis e³
of the snatch block d³ is also prolonged and formed to be actuated in the same
manner as the axis c² of the pulleys, and both ends of each of the axes c² and e³
may be formed in the same manner, in which case four levers or other devices
for the same purpose could be applied at once. The roller or rollers g²,
running on the pin or rivet f, is for the purpose of preventing the chain
passing, if the said chain is out of gear with the pulleys a³ and 6³, as herein.
before explained, and to force back any link which may have begun to rise
from its place in the periphery of either of the pulleys. The weight or object
to be raised is attached to the block d³. When the pulleys have the respective
diameters represented, no break is needed to prevent the weight running back,
as in practice the friction in the machine is found to effect the same object.
A continuous lift may be obtained by placing in each of the loops h and i a
block similar to the block d³, Figures 4 and 5. Each of the two blocks in
the loops and i alternately descends and ascends (one ascending while the
other descends) as the axes and are alternately turned in a different
direction. A chain with links sufficiently large to take the hooks of the
block d³, and the other similar block in the loop h being connected with the
object to be moved, the said chain may be drawn towards the pulleys a³ and 63
continuously by attaching to it alternately the block in the loop hand that in
the loop i, and reversing the rotation of the axes c and e³. In pulling
vertically, the slack loop h is kept true on the pulleys by its own weight.
When pulling in a direction varying much from a vertical one, the slack loop h
must have some strain upon it enough to keep it "taut" and true on the
pulleys, as is effected by gravity when it hangs vertically.
Having now described the nature of my Invention, and the manner of
carrying the same into effect, I wish it to be understood that I do not limit
myself to the precise details herein described and represented, as the same may
be varied without departing from the nature of my said Invention; but I claim
as my Invention the new or improved pulley herein-before described and
illustrated in the accompanying Drawing, that is to say, a pulley consisting of

page_text: an axle of different diameters in different parts, or consisting of two or more
single pulleys of different diameters, the said pulleys being fixed together or
fixed upon the same axis, an endless chain being passed twice over the pulley
in the manner described, and forming two depending loops, in one or both of
which loops is a snatch block, to which the article to be moved is connected.
In witness whereof, I, the said Thomas Aldridge Weston, have hereunto
set my hand and seal, this Twenty-first day of October, in the year
of our Lord One thousand eight hundred and fifty-nine.
Witness,
RICHARD SKERRETT,
THOMAS ALDRIDGE WESTON. (L.S.)
Clerk to George Shaw.