Improvements in Differential Hoisting Tackle.
Year: 1893

page_text: Date of Application, 13th June, 1893
Complete Specification Left, 12th Mar., 1894-Accepted, 5th May, 1894
PROVISIONAL SPECIFICATION.
Improvements in Differential Hoisting Tackle.
I, WILLIAM SCHERMULY, of No. 62, Stainsby Road, Poplar, in the County
of Middlesex, Rope Splicer, do hereby declare the nature of this invention to be
as follows:
My invention related to improvements in that class of differential hoisting tackle
in which the sheaves of the top block are separate from each other and from their
axle and are provided with a locking mechanism by means of which they can be
held together at will.
The principal member of the locking mechanism usually employed is a chain
pulley adapted to travel to and fro upon a threaded continuation of the axle of the
top block. The loose ends of the chains or cords pendent from the said pulley are
made fast to the ends of a stiff bar which carries a weight adapted to slide there-
upon. When the unlocking pulley is in either terminal position, the bar is vertical
or nearly so. The weight is then at the lower end of it in the angle made by that
end with the adjoining portion of the chain or cord, and holds the bar in that
position. As the unlocking pulley is being moved into its opposite terminal
position, the bar is inverted end wise, whereupon the weight slides down it to the
other end of it into the angle made by that end with its adjoining portion of the
chain or cord and holds the bar in that position.
A modification of the above described locking mechanism consists in pivotting
the bar upon or to the frame of the top block, in the proper plane for engaging by
its outer end or nose with ratchet teeth on or in the recesses in the periphery of the
unlocking pulley, so as to prevent it being moved in the reverse direction until
after the bar has been turned up. When the pulley has been traversed into its
opposite terminal position, the bar is turned into its original position, and will then
lock the pulley by standing close up to the side of it. The sliding weight, or
as much of it as may be desirable, is incorporated with the outer end of
the rod.
An additional sheave may be added to the top block to be used in conjunction
with a similar additional sheave on the axle of the travelling block. The additional
pulley on the top block is mounted upon a continuation of the axle of the latter
and has a suitable frame provided to enclose it. It may be either in one piece with,
or separate from, the adjacent sheave of the top pulley.
There is a guiding loop provided for the tall when the latter has a standing part
made in it by making a link of it fast to the travelling block. This loop stands
up above the sheave of the travelling block and receives that portion of the fall
which is at any moment between the point of attachment to the travelling block
below and the top block above.
To prevent the sheave getting off one sheave of the top block on to the other
by riding up and over the dividing flange, I provide a guard consisting of a half
circle having a radius a little longer than that of the larger sheave. It held
above the two sheaves and in the plane in which their adjacent faces meet, by
being made fast to the bridge piece of the frame of the block.
Dated this 13th day of June 1893.
PHILLIPS & LEIGH,
Agents for the Applicant.

page_text: COMPLETE DIBUITIVATION
Improvements in Differential Hoisting Tackle.
I, WILLIAM SCHERMULY of No. 62 Stainsby Road, Poplar, in the County of
Middlesex, Rope Splicer, do hereby declare the nature of this invention and in what
manner the saine is to be performed, to be particularly described and ascertained
in and by the following statement :-
My invention relates to improvements in that class of differential hoisting tackle
in which the sheaves of the top block are separate from each other and from their
axle and are provided with a locking and unlocking mechanism by means of which
they can be held together at will.
In order that the invention and the means by which the same is to be carried
into effect may be thoroughly understood, I will now describe it and them in detail,
referring in so doing to the accompanying figures which are to be taken as part of
this Specification and read therewith.
Figures 1 and 2 are side and front elevations illustrating one of my improved
devices for holding the pulley of the locking and unlocking mechanism in either of
its terminal positions.
Figure 3 is a side elevation illustrating an improved general construction of
hoisting tackle.
Figure 4 is a side elevation of a standing block fitted with my improved chain
guard as well as with the substitute improved device for holding the pulley of the
locking and unlocking mechanism in either of its terminal positions.
Figure 5 is a front elevation illustrating a modification, in respect of the standing
block, of the improved general construction of hoisting tackle illustrated in
Figure 3, and also a substitute improved device for holding the pulley of the
locking and unlocking mechanisin in either of its terminal positions.
Figure 6 is a side elevation of the standing block illustrated in Figure 5.
a is the well known hook by which the tackle is suspended. The frame of the
standing block consists of three pieces, the two cheeks b, b' and the bridge piece c.
The latter receives the hook a which is connected to it after the manner of a swivel
in the well known way. d is the axle of the standing block. According to the
construction of the frame illustrated in Figure 2, one cheek, 61, is cranked at a
right angle twice, once just below the bridge piece c and outwards, and once
downwards. The object of this double cranking is to make room inside the frame
for the locking and unlocking mechanism. e is the smaller and f, the larger sheave.
They are of the well known chain type, and each is separate and distinct from the
other and both are loose upon the axle d. Referring to Figures 3 and 5, g, g are a
pair of sockets formed through the sheave e, one on each side of the axle d, both
parallel with it and equidistant from it. There are four sockets g' in the sheave f
equidistant from each other and at the same distance from the axle d as the
sockets 9. 9, 9 are a pair of bolts. They are of the same length as two aligned
sockets g, g¹ in which they are adapted to be moved to and fro by the motion of
the pulley of the locking and unlocking mechanism. This pulley is mounted
upon a screw cut upon the axle d along which it can be traversed in either
direction by being rotated accordingly. Its periphery may either be of the chain
type as illustrated in Figures 3, 4 and 5, or smooth faced as illustrated in Figure 2.
For the purpose of rotating it in either direction, it is provided with two hand
chains or cords h, h', according to its periphery, which are made fast by one end
of each to the latter and hang down from opposite sides thereof, respectively, as
shown in Figure 2. The connection between the locking bolts g and the pulley 9°
may be as illustrated in Figures 3 and 5, according to which the heads 9 of the
bolts are held within an annular groove 9 in the side of the pulley 9, but separate
from it, by a detaining ring g' which stands outside the said heads in the relative

page_text: position shewn in the figures last mentioned. Or the pulley 9ª may carry a con--
centric ring fast on its side, and having radial studs 97 projecting into a groove
in the periphery of a collar 98 adapted to slide upon the plain portion of the axle d
and having the heads of the locking bolts g made fast to it. None of the foregoing-
devices form any part of the present invention. They are to be found fully
specified in my previous Patent 17857 1892.
The first part of the present invention relates to a device for holding the sheave.
locking and unlocking mechanism in either of its terminal positions upon the axle
of the standing block. It is illustrated in Figures 1 and 2. The two hand chains
or cords h, h', are of the same length so that when the unlocking pulley 9' is in
either of its terminal positions on the thread d, the bottom end of one of them is
lower than the other. This relative position is utilised for the purpose of this part
of my invention, by joining the said ends by a straight and rigid bar o which.
carries a sliding weight o'. This latter is shewn as a sphere having a diametrical
hole large enough to receive the bar o, but this detail may be modified to any
extent so long as the weight is heavy enough and can slide freely by gravity down
the bar. The chains or cords h, h¹ being in the relative position last described-
the one illustrated-the bar o will be more or less vertical; the weight at the
bottom of the bar and holding both chains or cords h, ', taut. The weight may
be lighter or heavier as may be required, according to the size of the tackle to
which it is to be applied. It must at least be heavy enough to prevent all
accidental traverse of the pulley g' upon its thread d². The full lines of the two-
figures, as far as they relate to this part of the invention, shew the cords, rod, and
weight in the position they occupy when the two sheaves e and f are locked
together. The dotted lines on the left hand side of Figure 1 shew an intermediate
position, the weight o¹ sliding in the direction of the arrow down the more than
half reversed rod. The corresponding set of dotted lines on the right hand of the
figure shew the cords, rod, and weight in the position they occupy when the two
sheaves e and fare unlocked from each other, which position is the opposite of
the one illustrated by the corresponding full lines of the two figures in question.
A substitute device for the same purpose as the one last described is illustrated
in Figures 4 and 5. p is a locking bar pivotted upon the frame of the standing
block in any convenient way or position, provided that its nose can (a) when the
pulley 9 is in one terminal position, stand between the flanges or shrouds of the
pulley 9 (or can engage with a ratchet wheel combined with the said pulley) so
as to prevent its traverse from that position towards the opposite one, as illus-
trated in Figures 4 and 5; and (6) stand by the side of the said pulley when it
is in the said opposite terminal position so as to prevent its traverse therefrom
towards the then opposite one. The locking bar p shewn as merely pivotted
and therefore adapted to be swung out and into engagement with the pulley g°,.
by hand. As a precaution against accidental disengagement, a weight adapted
to slide along the bar p may be combined therewith.
The second part of my invention consists in adding an additional sheave to
the standing block, to be used in conjunction with the similar additional sheave
on the axle of the travelling block. The additional second sheave on the axle
of the travelling block is not, as far as itself is concerned, a feature of the
present invention. Its use is, in conjunction with a rearrangement of the fall,
to convert a hoisting tackle into a double luff tackle, and both the last mentioned
additional sheave and the re-arrangement of the chain are fully illustrated in
Figure 2. A description of it is repeated here for the sake of making the scope
of the above mentioned second part of the present invention more distinct.
A device must be added to the frame of the standing block by means of which a
link of the fall can be easily made fast to the said block. Provided this condition.
is met, any type of device may be made use of. I have illustrated one which
satisfies the above condition, and has the merit of being exceedingly simple. This
is a hook m¹ to which the fall is caught by passing a link over it. It projects from
the frame of the standing block and, preferably, from the side opposite to the

page_text: locking and unlocking mechanism. is the additional sheave on the axle 1 of the
travelling block. The axle projects beyond the frame far enough to receive this
second sheave, which is prevented from coming off it by a nut or pin i.
The slack of the fall k, k¹ from the sheave e in the standing block is passed
round the additional sheave, then led up to the standing block and caught thereto
by passing one of its links over the hook m¹. Unlocking the sheaves e and f in the
standing block will complete the conversion.
This second part of the present invention is illustrated in Figures 3, 5, and 6.
9 is the additional sheave in the standing block. It is either in one piece with the
farger sheave as illustrated in Figure 3, or it may be separate and distinct
therefrom and be mounted upon a prolongation of the axle within a
supplementary frame g¹.
Instead of making the standing part on either the standing block or on the
travelling block, it may be made at any intermediate or convenient point within
reach of the hauling chain, by having a fixed stud around which the said chain
can be taken, as illustrated in Figure 5.
The third part of my invention relates to a device for guiding the fall from the
hook m on the travelling block (which hook is fully described in my said former
Patent) and is illustrated in Figures 3 and 5. s is a hook or open loop fast to and
standing up from the top of the travelling block. It receives, and allows to run
freely through it, that portion of the fall which is at any moment between the
point of attachment m to the travelling block below, and the standing block above.
The dotted lines to and from the point of attachment m and the hooks illustrate
clearly the nature and action of this part of the present invention.
The fourth part of my invention relates to a device adapted to prevent the chain
getting off one sheave of the standing block on to the other sheave, by riding up
and over the dividing flange. It is illustrated in Figures 4, 5, and 6. t is a semi-
circular guard concentric with the sheave and in respect of radius a little more
than that of the said dividing flange t which divides the two sheaves e and f, above
the upper half of which, and in the same plane, it is fixed by being made fast to
the bridge piece c in the relative positions illustrated in the said Figure 6.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. The herein before described device for holding the pulley of the locking and
unlocking mechanism in either of the terminal positions of its traverse, as set forth
with reference to Figures 1 and 2.
2. The hereinbefore described device for holding the pulley of the locking and
unlocking mechanism in either of the terminal positions of its traverse, as set forth
with reference to Figures 4 and 5.
3. The hereinbefore described general construction of hoisting tackle as set forth
with reference to Figures 3 and 5.
4. The combination of the sheaves of the standing block and the chain guard as
set forth with reference to Figures 3, 4, and 5.
1
1004
PHILLIPS & LEIGH,
22, Southampton Buildings, Chancery Lane, London, W.C.,
Agents for the Applicant.