IMPROVE- MENTS IN WORKING CORDS, STRAPS, OR CHAINS WITH PULLEYS, ALSO IN DIFFERENTIAL PULLEY BLOCKS, AND IN APPARATUS FOR PAWLING OR RETAINING
Year: 1866

page_text: LETTERS PATENT to Henry William Ley, of Bear Street, Leicester
Square, in the County of Middlesex, for the Invention of "IMPROVE-
MENTS IN WORKING CORDS, STRAPS, OR CHAINS WITH PULLEYS, ALSO IN
DIFFERENTIAL PULLEY BLOCKS, AND IN APPARATUS FOR PAWLING OR
RETAINING."
Sealed the 12th March 1867, and dated the 18th September 1866.
PROVISIONAL SPECIFICATION left by the said Henry William Ley at
the Office of the Commissioners of Patents, with his Petition, on the
18th September 1866.
I, HENRY WILLIAM LEY, of Bear Street, Leicester Square, in the County
of Middlesex, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN WORKING CORDS, STRAPS, OR CHAINS WITH POLLEYS, ALSO IN
DIFFERENTIAL PULLEY BLOCKS AND IN APPARATUS FOR PAWLING OR RETAINING," to
be as follows:
In working cords, straps, or chains with pulleys to prevent slipping when
a weight is attached I make use of rollers, between which and the pulleys
the cord, strap, or chain passes. Sometimes I use an endless band of flexible
material working over rollers so placed that it shapes itself to the circular

page_text: form of the cord, strap, or chain passing over the pulley; and as with increase
of weight the tendency of the cord, strap, or chain to slip increases I some-
times also so arrange that there is a corresponding greater pressure from the
rollers or band upon the cord, strap, or chain. In gearing chains with pulleys
otherwise I so dispose the chain that the links instead of arranging them-
selves in the plane of circular section and perpendicular to it arrange
themselves obliquely to those planes, and I more or less shape the periphery
of the pulley to the chain so disposed. Applied to differential pulley blocks
this disposition of the chain permits the difference between the numbers
of links engaged by the two pulleys, of which each of the said blocks consists
to be 1 or any multiple of 1 instead of 2 or its multiples as in diffential
pulley blocks now manufactured. Thus when an oval-link chain is so disposed
around a cylindrical pulley that the end view of a transverse section would
resemble a St. Andrew's cross, thus × ; its plan or projection upon the pulley
would present in its bounding lines a series of crusps, thus
Now in a pulley with rims or flanges so constructed as to present projections
corresponding to these cusps each link would abut against the projections next
it, and be similarly and separately engaged, thereby permitting the difference
between the numbers of links engaged by the two pulleys, of which a
differential pulley block consists to be made 1 or its multiples.
There is another mode by which the same result can be obtained even
with the ordinary disposition of chain and pulley where the links lie in the
plane of circular section and perpendicular to it. It is this, Twist each link
of an oval-link chain upon itself through a quarter of a revolution around its
longer axis; if the letter O represent a link before twisting, it will after
twisting be represented by two smaller o's, each of which, however, will be
perpendicular to the other, thus 6 Q. Such links can be geared with a
pulley by projections against which each link abuts. I also make the difference
between the numbers of links engaged by the two pulleys constituting a
differential pulley block any number of fractional parts of a link by various
constructions of gearing chain and arrangements of pulley periphery with
respect to them as follows:-With gearing chains as ordinarily used the
portions engaging with the pulley periphery at one revolution fall into the
places vacated by similar engaging portions at the previous revolution; as I
arrange them this may or may not be the case according to the diameter of
the pulley. and the difference required between the numbers of links engaged
by the two pulleys constituting the block. Illustrating this by one case,―
Suppose an ordinary oval-link chain of which every n-th link has similar and
similarly situated projecting studs for the engagement of which with the

page_text: pulley proper provision is made. Now if one pulley of a differential pulley
block be constructed for a links, a being a multiple of n, each place occupied
by a stud at one revolution will be occupied by another stud at the next
revolution. Let the portions of the pulley periphery between each two such
places be divided into equal parts, and each part have like provision for the
engagement of the studs. The circumference of the second pulley of the
block can then be made to differ by the length of one or more of these parts
from the first, and the studs of the chain be made to occupy at one revolution
not the same places as at the previous revolution, but places removed from
them by the distance of one or more of these parts.
I also use another method by which the difference between the numbers of
links engaged by the two pulleys constituting a differential pulley block can
be made fractional and indefinitely modified. As now constructed these two
pulleys are rigidly united; I do not unite them rigidly, but attach them to
each other by gearing, so that whilst both are revolving by means of the chain
one of them is also slowly revolving in the same or in the opposite direction,
as may be required, by means of the gearing. In cases where I wish to apply
power to differential pulley blocks by means of a pinion I construct the pinion
so that it shall gear with the projections on the pulley by which the links of
the chain are engaged; sometimes I find it convenient to make use of the
links themselves as teeth, and apply power to them by a pinion either where
they follow in a straight line as a rack, or where they pass over the pulley as a
wheel; similarly, without special reference to differential pulley blocks I some-
times use the strands of a cord as teeth.
Another mode in which I construct differential pulley blocks is this:-The
pulleys over which the chain passes contain no provision for the engagement
of the chain links, but I use other pulleys between which and the above
pulleys the chain passes; and I construct these other pulleys so that the
required engagement shall take place with them. In differential pulley blocks
thus constructed it is not requisite that the pulleys over which the chain
passes should be rigidly united.
My improvements in apparatus for pawling or retaining are effected by the
use of a worm and gearing to drive that worm, so adjusted that the worm
instead of driving shall follow the teeth of the wheel to which it is applied
in whichever direction that wheel may by other means be driven, but shall
pawl or retain that wheel on its becoming the driving power.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Henry William Ley in the Great Seal Patent Office
on the 18th March 1867.
TO ALL TO WHOM THESE PRESENTS SHALL COME; I, HENRY
WILLIAM LEY, of Bear Street, Leicester Square, in the County of Middlesex,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eighteenth day of September, in the year of our Lord
One thousand eight hundred and sixty-six, in the thirtieth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Henry William Ley, Her special licence that I, the said Henry William Ley,
my executors, administrators, and assigns, or such others as I, the said
Henry William Ley, my executors, administrators, and assigns, should at any
time agree 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 "IMPROVEMENTS IN
WORKING CORDS, STRAPS, OR CHAINS WITH PULLEYS, ALSO IN DIFFERENTIAL PULLEY
BLOCKS, AND IN APPARATUS FOR PAWLING. OR RETAINING," upon the condition
(amongst others) that I, the said Henry William Ley, my executors or
administrators, 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 William Henry Ley, 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, reference being had to the Drawings hereunto
annexed, that is to say:-
Figures 1 to 4 are illustrations of my modes of working cords, straps, or
chains with pulleys; Figure 1 is a front elevation of an arrangement for
working an oval link chain with a pulley; A is the pulley; B is a roller
whose axis is in the pulley framing, and which has projections 6, 6, 6, and c, c, c,
against which the links lying flat on the cylindrical face of A and transverse
to these respectively abut; A itself is furnished with recesses or hollows a, a, a,
to receive these same transverse links. The peripheries of both A and B are

page_text: arranged for 24 links. It is manifest that this system of using a roller B in
combination with a pulley may be variously modified; for example, by the
numbers of links engaged by A and B being unequal; also by modification of
the engagement of the links. By suitable modifications of the peripheries of
A and B, other than oval link chains may be used; B may be made by a
spring pressing on its axis, say to press a chain upon A, and with the rollers
exerting pressure cords or straps may also be thus worked.
Figure 2 is a side elevation of an arrangement for working a cord or strap
with a pulley, so that the pressure upon the cord or strap increases with the
weight; A is the pulley, revolving on an axis at B in the frame C, B, which
swings on an axis at C in the pulley framing D, D; E is a roller, whose axis
is also in D, D. A weight attached at F to a cord or strap passing over A
between A and E, causes C, B, to move in the direction of the arrow; the
cord or strap is thereby pressed between A and E, a pressure which increases
with the weight.
Figure 3 is a side elevation of another arrangement for working a cord or
strap with a pulley, so that the pressure upon the cord or strap increases with
the weight; A is the pulley; a, a, a, is a flexible band working over rollers B,C,
and adapting itself to the circular part of the cord or strap passing over the
pulley; B revolves on an axis in the pulley framing D, D; C revolves on an
axis at C in a frame C, E, F, which swings on an axis at E, in D, D; F is
another roller revolving on an axis at F in the same frame C, E, F. A
cord G, G¹, passes over the pulley as shown between the band a, a, a, and A,
as also between F and A; a weight at G moves F and C in the direction of
the arrows and presses a, a, a, upon G, G¹, a pressure which increases with
the weight. The flexible band may be of undressed buffalo hide or other
materials, for instance of leather or wire. Both this and the preceding
arrangements (Figures 2 and 3) may be variously modified, either in the
positions of the axes of the swinging frames, or for using chains. The band
and roller B (Figure 3) may also be removed, provided the axis of the
swinging frame be so placed that C shall press upon the cord or strap. In
working cords, straps, or chains with pulleys as described, the pulleys or
rollers or both may, if desired, be covered with elastic material; also, for
smoothness of action both pulleys and rollers may be furnished with teeth
gearing into each other.
Figure 4 is a front elevation of an arrangement for gearing an oval link
chain with a pulley, so that the links passing over it shall dispose themselves
at angles of 45° or thereabouts with the circular faces of the pulley, and shall
gear by abutting against the ribs a, a, a. The periphery is arranged for

page_text: 24 links. The means of engagement of the links shown in the Drawing may
be modified and still retain the peculiarity of the links of a chain disposing
themselves at an angle of or of about 45° with the circular faces of a pulley;
and a pulley such as is represented in Figure 4 may be constructed in 2
pieces, so that it can be adjusted to more than one size of chain. If each of
the ribs a, a, a, were continued as represented by the dotted lines, and the
pulley consisted only of the cylindrical portions A, B, and such ribs, then the
distance between these like halves, and consequently the diameter of the pitch
line, might be varied, and the pulley adjusted for more than one size of
chain.
Figures 5 to 11 illustrate my constructions of differential pulley blocks.
Figures 5 and 6 illustrate a mode of making the difference between the
numbers of links engaged by the two pulleys, constituting a differential
pulley block 1 or its multiples.
Figure 5 represents a piece of oval link chain composed of links twisted
around their longer axes.
The portions b, b, b, are similar and perpendicular to a, a, a.
Figure 6 is a front elevation of a differential pulley block constructed for a
chain such as Figure 5 represents, and to make the difference between the
numbers of links engaged by the two pullies of the block one link. Figure 5
is for clearness sake drawn on a larger scale than Figure 6.
The projections a, a, a, a, a, a, on the cylindrical faces of the pulleys A and
B which constitute the block receive between them the portions a, a, a,
(Figure 5), of the chain links, and the grooves b, b, b, b, (Figure 6), receive the
portions b, b, b (Figure 5) of the chain links. The periphery of A is con-
structed for 10 links and that of B for 9 links. The portions a, a, a, b, b, b,
of the chain links, (Figure 5), are shown equal to each other, but this is not
essential, as the proportion between the parts of each link may be varied,
provided that where necessary the peripheries of the pulleys A and B be
modified accordingly. And as a pulley periphery can be made as shown to
engage with each link of such chains, the difference between the numbers of
links engaged by A and B can be made 1, as shown, or its multiples.
Figures 7 and 8 illustrate a mode of constructing a differential pulley
block so as to make the difference between the numbers of links engaged by
the two pulleys of which it consists fractional.
Figure 7 represents a piece of oval link chain, of which every fourth link
has similar and similarly situated projecting studs a, a, a, a.
Figure 8 is a front elevation of a differential pulley block constructed for
a chain such as Figure 7 represents, and to make the difference between the

page_text: numbers of links engaged by the two pulleys of the block 2 links. Figure 7
is for clearness sake drawn on a larger scale than Figure 8.
A and B are the two pulleys of the block; A is constructed to pass 20
links over in each revolution; B, to pass 173 links. A has 5 pairs of
recesses a, a, a, to receive the studs of the chain; B has 22 such pairs of
recesses. As A revolves studs fall at one revolution into the recesses vacated
by studs at the previous revolution; as B revolves in the direction of the
hands of a watch, suppose, as seen from the A side of B, studs fall at one
revolution (reckoning from the asterisk) into pairs of recesses a, a, a, at the
second revolution into a³, a, a, at the 3rd, 4th, and 5th revolutions into
a³, as, a³, a, a, a, and a³, a³, a³, respectively, and at the 6th into a, a, a, as
before. If instead of 22 pairs of recesses, B were constructed to have 21
such pairs, the difference between the numbers of links engaged by A and B
would be 33. If A were constructed to pass 20 links over in each revolu-
tion, and B 19 links, A would have 26 pairs of recesses and B 24 pairs.
Similarly, the difference between the numbers of links engaged by A and B
may be made other fractional parts of a link. Other gearing chains may
also with suitable provisions be similarly used.
Figure 9 is a front elevation of a differential pulley block constructed to
make the difference between the numbers of links passed over by either pulley
of the block whilst the other makes one revolution 106 of a link; A and B, the
the two pulleys of the block, are in this case separate. C is a spur wheel
of 22 teeth fixed concentrically to A; D, a spur wheel of 20 teeth fixed con-
centrically to B; E and F are spur wheels of 20 and 19 teeth respectively
rigidly united and gearing respectively with C and D. As power is applied
by means of the chain to A, say, C revolves, communicating motion to E
and F, and thus permitting D and B to revolve, B making more than one
revolution for one revolution of A, and passing 2016 links over for every 20
links passed over by A. In this case then a differential action is obtained
where the two pulleys of the block are united by gearing instead of being
rigidly united, and the difference between the numbers of links passed over by
either pulley whilst the other makes one revolution made 1 of a link. By
variations of the proportions between the wheels, by variations of the numbers
of links engaged. by A and B, and also by other combinations of gearing uniting
A and B the difference between the numbers of links passed over by one pulley
of a differential pulley block whilst the other makes one revolution may be made
other fractions of a link.
Figures 10 and 11 illustrate a mode of constructing differential pulley blocks
in which the links of the chain by which the block is worked are not engaged

page_text: by the pulleys over which the chain passes. Figure 10 is a front elevation of
a block of this kind, in which the pulleys over which the chain passes are not
rigidly united...
A and B are the pulleys over which the chain passes; C and D are
the pulleys engaging the links. The provision for engagement represented
has already been explained in the description of Figure 1. C and D are
rigidly united. By power applied to the chain passing over A, say, C and D
revolve, controlling the passing of the chain over B. D is constructed to
engage 22 links, and B to pass 24 links over in one revolution; C to engage
24 and A to pass over 22 links in one revolution. Figure 11 is a front
elevation of a block of this kind, in which the pulleys over which the chain
passes are rigidly united. A, B, C, D, are as before, except that A, B, are
rigidly united; and C, D, are not united. E, F, G, H, are spur wheels rigidly
united concentrically with A, B, C, D, respectively, E working with G, and
F with H. The action may be thus understood:-Suppose A to be of a size
necessary for 19 links, and E to have 19 teeth; B of a size necessary for 20
links, and F to have 20 teeth; C to engage 18 links, and G to have 18
teeth; D to engage 20 links, and H to have 20 teeth. Suppose power applied
to the chain passing over B; then the passing of 20 links over B will turn D
and (by means of H and F) B through one revolution. But A and E being
rigidly united to B will also make one revolution. Thus G and C will
make revolutions, and 19 chain links will pass over A in its revolution.
.
Figures 12 to 18 illustrate my mode of pawling or retaining applied to a
crab. Figure 12 is a side elevation (the handle and a portion of the framing
being removed); Figure 13 is a front elevation; and Figure 14 a partial
projection on a plane perpendicular to the plane of the paper and parallel to
the line G, H. A, is the pinion having a slight circular play on its shaft, as
shown in Figures 15 and 16; B, is the wheel of the crab; C a bevel wheel
keyed on the pinion shaft and working D another bevel wheel on the shaft of
a screw or worm E whose bearings (not shown in Figures 12 and 13, but
shown in Figure '14) are attached to the crab framing. D like A has a slight
circular play on its shaft as shown in Figures 17 and 18. The screw or
worm E has one or more threads and gears with the teeth of a wheel F
fixed on the shaft of B. The action is thus:-As the pinion shaft revolves in
the direction of the hands of a watch, say by power applied to it, the play
between itself and its pinion is caught up (Figure 15), and also the play
between D and the shaft of worm E (Figure 17, D being seen from the
E side of it), which worm E is thus caused to revolve; at the same time
A is turning B and lifting W, the weight applied; the worin E. being so

page_text: adjusted as to follow the teeth of F as that revolves. Now if there were not
the play spoken of, and the power were suddenly removed, the various wheels
would time their revolutions together, and B would cause A and C to revolve
communicating motion to D and to the worm E which would thus turn in
the opposite direction and not interfere with the descent of W; but as D'can
turn to a small extent in the opposite direction (Figure 18) without turn,
ing E, the back lash between E and the teeth of F is caught up by F before
motion is communicated to E, F thus becomes pawled and W remains
suspended. If it be required to lower the weight all that is necessary is to
apply power to the shaft of A in the direction opposite to that of the hands of
a watch, by which C will revolve and catch up the play between D and the
shaft of E, (Figure 18), also catching up at the same time the play between
itself and its pinion (Figure 16), and W will thus be permitted to descend.
Now suppose the handle let go during the lowering of W, the teeth of F and
the threads of E are already in close contact, F is therefore at once pawled,
and can do nothing towards turning A from the position in which it is at the
time of releasing the handle (Figure 16) to the position into which it must
come (Figure 15) before motion can be communicated to the driving shaft
and hence to C, D, and E. Thus by the use of a worm E and gearing to
drive that worm so adjusted that instead of driving E follows the teeth of F
in raising W and controls the revolution of F in lowering W complete control
in lowering as well as raising is obtained, and also perfect safety in the event
of the power being removed. Workmen, moreover, are relieved from the
strain of the weight in lowering. With suitable provision F may be dispensed
with and B may be used instead thereof. I do not confine myself to the
precise arrangements for pawling here described and shown, as the same may
be modified in its details.
Having now particularly described and ascertained the nature of my Inven-
tion, and the manner in which the same is to be performed, I proceed to
state what I claim as my Invention,―
First, preventing the slipping of cords, straps, or chains when worked with
pulleys, either by the use of rollers between which and the pulleys such cords,
straps, or chains pass, or by the use of an endless band between which and a
pulley, a cord, strap, or chain passes, substantially as described.
Second, the constructing of pulleys so that the links of the chains passing
over them shall arrange themselves obliquely to the circular faces of the
pulley as described with reference to Figure 4.
Third, the constructing of differential pulley blocks to be used in combi-
nation with chains consisting of links of the description shown in Figure 5.

page_text: Fourth, the constructing of "differential pulley blocks to work with chains,
as described with reference to Figures 7 and 8, where similar successive
portions of the chains do not fall into the same position in two successive
revolutions.
Fifth, the constructing of differential pulley blocks wherein the two pulleys
constituting the block are united by gearing for the purpose of obtaining the
differential action.
Sixth, the constructing differential pulley blocks so that the pulleys over
which the chain passes contain no provision for the engagement of the chain
links, the required engagement taking place with other pulleys between which
and the above pulleys the chain passes.
Seventh, combining mechanism for pawling or retaining by a worm which
does not also drive.
In witness whereof, I, the said Henry William Ley, have hereunto
set my hand and seal, this Sixteenth day of March, in the year of our
Lord One thousand eight hundred and sixty-seven.
HENRY W. LEY. (L.S.)