IMPROVEMENTS IN APPARATUS FOR RAISING, LOWERING, MOVING, OR TRANSPORTING HEAVY BODIES
Year: 1865

page_text: LETTERS PATENT to Thomas Aldridge Weston, James Tangye, and
Richard Chapman, all of Birmingham, in the County of Warwick,
Engineers, for the Invention of "IMPROVEMENTS IN APPARATUS FOR RAISING,
LOWERING, MOVING, OR TRANSPORTING HEAVY BODIES."
Sealed the 8th May 1866, and dated the 14th November 1865.
PROVISIONAL SPECIFICATION left by the said Thomas Aldridge Weston,
James Tangye, and Richard Chapman at the Office of the Com-
missioners of Patents, with their Petition, on the 14th November
1865.
We, THOMAS ALDRIDGE WESTON, JAMES TANGYE, and RICHARD CHAPMAN,
all of Birmingham, in the County of Warwick, Engineers, do hereby declare
the nature of the said Invention for "IMPROVEMENTS IN APPARATUS FOR RAISING,
LOWERING, MOVING, OR TRANSPORTING HEAVY BODIES," to be as follows:-.
This Invention relates to certain improvements upon the Invention for
which Letters Patent were granted to Thomas Aldridge Weston on or about the
25th of April 1859, No. 1033, and has for its object the affording of greater

page_text: facility for working directly by hand power the arrangement of differential
pulley block wherein three or more pullies are employed on one axle, and
also affords facility for working such an arrangement by mechanical power,
whether such power be set in motion by hand, as, for example, by the aid of
a crab or windlass which may be applied to a crane or otherwise employed
or be worked by a steam engine or other prime mover, in which case a wider
range is also afforded in the lifting power obtained than by the method set
forth in the Specification referred to, by simply varying the diameter of the
drum of the primary actuating crab or windlass.
According to this Invention it is proposed to employ three or more sheaves
revolving together on one axis, two of the said sheaves being of equal diameter;
over these sheaves is passed an endless chain so as to leave three or more
pendent loops, in some of which loops single sheave snatch blocks are sus-
pended with a view to obtaining a continuous lift or haul, whilst one of such
loops is left slack or free for the purpose of actuating the apparatus. By
having two of the sheaves in the fixed block of the same diameter the slack
pendent loop which hangs from the opposite sides of such sheaves will never
vary in length except by the stretching of the chain in wear, thus affording
facility for driving such chain or loop by power from any fixed point by the
aid of a crab or windlass. One of the two sheaves from which the slack loop
is suspended is capable of being disconnected from the rest, so as to enable
more or less chain to be taken in or let out from such loop by turning the
said pulley in one direction or the other, whilst the rest are held stationary, or
vice versa, whereby the amount of lift or range of the snatch blocks in the
other two loops may be varied as circumstances may require, after which the
said sheave is again coupled by a pin, bolt, key, or other simple contrivance
with the rest of the sheaves in the fixed block. In some cases, when a con-
tinuous lift is not required, three or more loops may be employed in combi-
nation with only one snatch block, such snatch block being transferred from
one loop to another according to the speed or power required, thus making
one tackle serve the purpose of two or more separate tackles of different
powers; and when two snatch blocks are employed with a view to obtaining
a continuous lift, the chain may be passed over or transferred to any one of the
intermediate sheaves between the two sheaves of equal diameter, whereby the
power of the continuous hauling apparatus may be varied in the same tackle.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Thomas Aldridge Weston, James Tangye, and Richard
Chapman in the Great Seal Patent Office on the 14th May 1866.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, THOMAS
ALDRIDGE WESTON, JAMES TANGTE, and RICHARD CHAPMAN, all of Bir-
mingham, in the County of Warwick, Engineers, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourteenth day of November, in the year of our Lord
One thousand eight hundred and sixty-five, in the 29th year of Her reign, did,
for Herself, Her heirs and successors, give and grant unto us, the said Thomas
Aldridge Weston, Weston James Tangye, and Richard Chapman, Her special
license that we, the said Thomas Aldridge Weston, James Tangye, and
Richard Chapman, our executors, administrators, and assigns, or such others as
we, the said Thomas Aldridge Weston, James Tangye, and Richard Chapman,
our executors, administrators, or 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
APPARATUS FOR RAISING, LOWERING, MOVING, OR TRANSPORTING HEAVY BODIES,"
upon the condition (amongst others) that we, the said Thomas Aldridge
Weston, James Tangye, and Richard Chapman, our executors or adminis-
trators, by an instrument in writing under our hands and seals, or under
the bands and seals of one of us, 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 we, the said Thomas Aldridge Weston, James
Tangye, and Richard Chapman, do hereby declare the nature of our said
Invention, and in what manner the same is to be performed, to be parti-
cularly described and ascertained in and by the following statement, reference
being had to the accompanying Drawings, and to the letters and figures,
marked thereon, that is to say:-
Our said Invention relates to certain improvements upon the Invention for
which Letters Patent were granted to Thomas Aldridge Weston on or about
the 25th of April 1859, No. 1033, and has for its object the affording of greater.
facility for working directly by hand power the arrangement of differential

page_text: pulley block wherein three or more pulleys are employed on one axle, and
also affords facility for working such an arrangement by mechanical power,
whether such power be set in motion by hand, as, for example, by the aid of
a crab or windlass, which may be applied to a crane or otherwise employed,
or be worked by a steam engine or other prime mover, in which case a wider
range is also afforded in the lifting power obtained than by the method set
forth in the Specification referred to, by simply varying the diameter of the
drum of the primary actuating crab or windlass.
According to this Invention it is proposed to employ three or more sheaves
revolving together on one axis, two of the said sheaves being of equal diameter;
over these sheaves is passed an endless chain so as to leave three or more
pendent loops, in some of which loops single sheave snatch blocks are sus-
pended with a view to obtaining a continuous lift or haul, whilst one of such
loops is left slack or free for the purpose of actuating the apparatus. By having
two of the sheaves in the fixed block of the same diameter the slack pendent
loop which hangs from the opposite sides of such sheaves will never vary in
length except by the stretching of the chain in wear, thus affording facility for
driving such chain or loop by power from any fixed point by the aid of a crab
or windlass. One of the two sheaves from which the slack loop is suspended
is capable of being disconnected from the rest, so as to enable more or less
chain to be taken in or let out from such loop by turning the said pulley in
one direction or the other, whilst the rest are held stationary, or vice versa,
whereby the amount of lift or range of the snatch blocks in the other two
loops may be varied as circumstances may require, after which the said sheave is
again coupled by a pin, bolt, key, or other simple contrivance with the rest of
the sheaves in the fixed block. In some cases, when a continuous lift is not
required, three or more loops may be employed in combination with only one
snatch block, such snatch block being transferred from one loop to another
according to the speed or power required, thus making one tackle serve the
purpose of two or more separate tackles of different powers; and when two
snatch blocks are employed with a view to obtaining a continuous lift the chain
may be passed over or transferred to any one of the intermediate sheaves
between the two sheaves of equal diameter, whereby the power of the
continuous hauling apparatus may be varied in the same tackle.
And in order that our said Invention may be fully understood we shall
now proceed more particularly to describe the same, and for that purpose we
shall refer to the several Figures on the Sheet of Drawings hereunto annexed,
the same letters of reference indicating corresponding parts in all the
corresponding. Figures.

page_text: Fig. 1 of the annexed Sheet of Drawings represents a perspective view,
and Fig. 2a vertical section of one modification of our improved differential
pulley block.
In this arrangement A is the fixed block, containing three sheaves a, a¹, and b,
which are made to revolve together upon or with the axle c. Each sheave is
grooved and provided with "bits" or lateral projections (shown more clearly
in Figs. 3 and 4) from the inner sides of their flanges, which take into the
spaces between the ends of those links of the endless chain which lie flatwise
upon the periphery of the sheave, in order to prevent the slipping of the chain
over the sheaves, it being important in all these modifications that the links
of the chain should in fact gear into the peripheries of the sheaves. Two of
these sheaves (for example a and a¹) are to be of equal diameters, the central
one being either of a smaller diameter or of a larger diameter, as shown in the
Drawings. B is an endless chain, the links of which must be accurately
made so as to gear into the spaces between the "bits" or lateral projections
inside the flanges or grooves of the sheaves a, a', and b. This chain is prevented
from riding or escaping from the grooves of the sheaves by the guard or
protector B', placed across the frame of the block parallel to the axis of the
sheaves. C and D are single sheave snatch blocks provided each with a hook
or other attachment e, f, for connection with any hauling chain or rope
attached to the body to be moved, or for direct connection with the loads to
be raised or lowered. The endless chain B is passed over the several sheaves
a, a, b, in the following manner, reference being had more particularly to the
Diagram Fig. 1. Commencing with the sheave a, the chain is passed upwards
from the back of that sheave over the upper surface of the groove therein,
and is then carried downwards and passed under the pulley in the single
sheave snatch block C, from the front to the back thereof. It is then carried
upwards, thereby forming the first loop, and enters the back of the groove of
the central sheave b of rather larger diameter than the outer ones. From the
front of this sheave the chain again descends, and is passed under the pulley
of the single sheave snatch block D from the front to the back, whence it
rises so as to form the second loop, and is passed over the sheave a¹ of the
fixed block from the back to the front, it then descends to any convenient
distance, and is united to the corresponding end of the chain, which hangs
from the back of the sheave a, thus forming the third loop E, which hangs
freely without any snatch block therein, and serves solely for actuating
the tackle by hauling on one or the other side thereof, as shown in Figure 1.
By making the sheaves from which the actuating or slack loop E hangs of equal

page_text: diameters, no variation in the length of such loop is effected when the tackle
is in use, and in practice this arrangement will be found to present several
important advantages.
When using this improved differential tackle, whichever direction the loop
E of the endless chain is pulled, one of the snatch blocks C, D, will ascend
whilst the other is descending, and as a separate free loop E is provided for
actuating the apparatus, it can be readily put in motion without endangering
the fingers by grasping that portion of the chain which contains the rising
and falling snatch blocks, and thus a continuous lift or haul may be obtained
with perfect safety to the operator, it being simply necessary to couple the
lower snatch block to the main hauling chain or to the lashing chain attached
to the body to be moved or lifted, and to disconnect the upper snatch block,
when by reversing the motion of the endless chain the upper snatch block
will descend and the lower one rise to its full range.
The Drawing Figure 2 illustrates also the mode of varying the range of lift
or haul of the apparatus by taking up or letting out chain from the slack
loop; this is effected by disconnecting the sheave c from the rest by removing
or unscrewing the coupling pin g, when the sheave a¹ may be rotated inde-
pendently of the others, or vice versa, and the two snatch blocks either raised
or lowered by taking in or letting out more chain from the loose loop E.
When the range has been adjusted the coupling pin g is again inserted, and
the tackle used as before.
Figure 3 represents a front elevation of a continuous hauling tackle wherein
an endless chain B is used in combination with a set of five sheaves, of which
the two a, a¹, are of equal diameter. Figure 3* is a diagram of the same,
showing more clearly the course of the chain. By transferring the chain B
from one sheave to another of the remaining sheaves 1, 2, 3 of the block
(which are of different diameters), a variation in the power may be obtained,
but in all cases the slack loop E should hang from the two equal sized
sheaves a, a¹.
Figure 4 is a front elevation, and Figure 4 a diagram, shewing the applica-
tion of four sheaves (two of which a, a', are of equal diameters), whilst the
other two 1, 2, are of different diameters, in combination with four loops of an
endless chain B, the loop E of the four forming the actuating loop. One
snatch block C is used, which is transferred from one loop to another of the
three remaining loops, according to the power required.
By the arrangements shown at Figures 3 and 4 one set of tackle will give
different speeds and power in lieu of using separate tackle for different speeds

page_text: and power, and in all cases the length of the actuating loop E of the chain
never varies during operation, which is in fact the main distinguishing feature
of our present Invention.
Having now described and particularly ascertained the nature of our said
Invention, and the manner in which the same is or may be used or carried
into effect, we would observe in conclusion that what we consider to be novel
and original, and therefore claim as the Invention secured to us by the herein-
before in part recited Letters Patent is,―
First, the making of two of the sheaves of differential pulley blocks which
contain three or more sheaves of equal diameters, and suspending the slack or
actuating loop of the endless chain therefrom, whereby the length of such
loop will not vary when the tackle is in operation, substantially as herein-
before described.
Second, the making of one of the sheaves from which the slack or actuating
loop is suspended (when three or more sheaves are employed) capable of
being disconnected from the rest for the purpose of varying the range of lift or
haul, by taking in or letting out chain from the slack loop, substantially as
herein-before described.
Third, the modes of varying the speed and power of a differential pulley
block by transferring a single snatch block from one to another of two
or more loops suspended from sheaves of different diameters in the said
differential pulley block, or by transferring the chain from one to another of
two or more sheaves of different diameters in the said differential pulley
blocks, substantially as herein-before described and illustrated by Figures 3
and 4 of the Drawings.
In witness whereof, I, the said James Tangye, on behalf of myself and
the said Thomas Aldridge Weston and Richard Chapman, have here-
unto set my hand and seal, this Eleventh day of May, in the year of
our Lord One thousand eight hundred and sixty-six.
JAMES TANGYE. (L.S.)