Improvements in Differential Pulley-blocks.
Year: 1890

page_text: Date of Application, 9th Jan., 1890
Complete Specification Left, 26th Sept., 1890-Accepted, 8th Nov., 1890
PROVISIONAL SPECIFICATION.
Improvements in Differential Pulley-blocks.
We GEORGE TANGYE of the firm of Tangyes Limited of Cornwall Works
Soho in the County of Stafford Engineers and JOHN NICHOLAS FLOYD of Cornwall
Cottage Murdock Road Handsworth in the County of Stafford Mechanical Engineer
do hereby declare the nature of this invention to be as follows :-
:-
Our invention consists of the improvements hereinafter described in the differential
pulley blocks commonly known as Weston's differential pulley blocks and in all kinds
of differential pulley blocks of the same type or modified types.
Our invention has reference principally to the connection of the hook (or a sub-
stitute for the hook such as a ring) to the bottom block of differential pulley blocks
but our said invention may also be applied to the connection of the hook or substitute
for the hook to the top block of differential pulley blocks.
We will describe our invention as applied to the bottom block of the differential
pulley block to which bottom block it is particularly applicable. The hook (or sub-
stitute for the hook) is usually connected directly to an eye or head at the bottom of
the middle downward prolongation of the frame or straps of the pulley block so that
it is often necessary to incline the block before the hook can be hooked to the load
to be raised and lowered the inclination thus given to the block sometimes disengaging
the pulley of the bottom block from the loop of the winding chain. By the use of
our invention the connecting of the hook of the bottom pulley with the weight is
much facilitated and the disengaging of the pulley from the loop is avoided. Our
said invention consists in making the hook (or its substitute) hang from the frame or
straps of the bottom block by means of a chain or other flexible or jointed connection
instead of the method of connection heretofore used whereby the lifting or inclining
of the hook to hook it to the weight is effected without interfering with the normal
vertical position of the bottom block.
We prefer to fix the ends of the chains or flexible connections to the forked ends
of the straps or frame of the pulley block and to suspend the hook to the lower ends
of the chains or flexible connections in a line with the pin or axis on which the pulley
turns and somewhat below the said pulley but we do not limit ourselves thereto as
the chains carrying the hook may be suspended from the pin or axis of the pulley or
from other convenient part or parts of the pulley frame or straps.
Various modes of fastening the chains or flexible connections to the block frame
and to the cross head carrying the hook may be used and the hook may either be
rigidly secured to the cross head or swivel in it. But the hook may be secured to
the suspending chain or flexible connection without the use of a cross head.
When a chain or flexible connection is used between the hook and block frame of
the top block the suspending of the differential pulley block is facilitated but the
flexible connection for the hook of the bottom block may be used alone or in
combination with a flexible connection for the hook of the top block.
Dated this Ninth day of January 1890.

page_text: COMPLETE SPECIFICATION.
Improvements in Differential Pulley-blocks.
We GEORGE TANGYE of the firm of Tangyes Limited of Cornwall Works, Soho in
the County of Stafford, Engineers, and JOHN NICHOLAS FLOYD of Cornwall Cottage
Murdock Road, Handsworth in the County of Stafford Mechanical Engineer do
hereby declare the nature of our invention and the manner in which the same is to be
performed to be particularly described and ascertained in and by the following
statement:
Our invention consists of the improvements hereinafter described in the differential
pulley blocks commonly known as Weston's differential pulley blocks and in all kinds
of differential pulley blocks of the same type or modified types.
Our invention has reference principally to the connection of the hook (or a sub-
stitute for a hook such as a ring) to the bottom block of differential pulley blocks
but our said invention may also be applied to the connection of the hook or substitute
for the hook to the top block of differential pulley blocks.
We will describe our invention as applied to the bottom block of the differential
pulley block to which bottom block it is particularly applicable.
The hook (or substitute for the hook) is usually connected directly to an eye or
head at the bottom of the middle downward prolongation of the frame or straps of
the pulley block so that it is often necessary to incline the block before the hook can
be hooked to the load to be raised and lowered the inclination thus given to the block
sometimes disengaging the pulley of the bottom block from the loop of the winding
chain. By the use of our invention the connecting of the hook of the bottom pulley
with the weight is much facilitated and the disengaging of the pulley from the loop
is avoided.
Our said invention consists in making the hook (or its substitute) hang from the
frame or straps of the bottom block by means of a chain or other flexible or jointed
connection instead of the method of connection heretofore used whereby the lifting
or inclining of the hook to hook it to the weight is effected without interfering with
the normal vertical position of the bottom block.
We prefer to fix the ends of the chains or flexible connections to the forked ends
of the straps or frame of the pulley block and to suspend the hook to the lower ends
of the chains or flexible connections in a line with the pin or axis on which the pulley
turns and somewhat below the said pulley but we do not limit ourselves thereto as
the chains carrying the hook may be suspended from the pin or axis of the pulley or
from other convenient part or parts of the pulley frame or straps.
Various modes of fastening the chains or flexible connections to the block frame
and to the cross head carrying the hook may be used and the hook may either be
rigidly secured to the cross head or swivel in it. But the hook may be secured to
the suspending chain or flexible connection without the use of a cross head.
When a chain or flexible connection is used between the hook and block frame of
the top block the suspending of the differential pulley block is facilitated but the
flexible connection for the hook of the bottom block may be used alone or in
combination with a flexible connection for the hook of the top block.
Figure 1 of the accompanying drawing represents in side elevation and Figure 2
in front elevation a differential pulley block to which our method of connecting the
hooks to the top and bottom blocks of the differential pulley block is applied.
The same letters of reference indicate the same parts in both figures.
a is the differential or top pulley of the block and b is the bottom pulley supported
in the loop c of the winding chain passing over the pulley a; d is the hand loop of
the winding chain for working the block as usual; e is the hook of the bottom
pulley block b on which the load to be raised or lowered is placed, the said hook e
being connected to the block by a chain (or other flexible or jointed) connection
according to our invention; ff are the straps constituting the frame of the bottom
block 6 between the forked ends of which straps the upper ends of the chains gg are

page_text: pinned or centred the lower ends of the said chains being secured by pins or centre³
to the cross head of the block frame carrying the hook e. The hook e is thus sus-
pended below the bottom block b in a line with the pin or axis 62 on which the pulley
turns by the chains g, g the flexibly suspended hook e being made to swivel in the
cross head or being rigidly connected to it. Or the hook e may be connected
directly to the suspending chain g, g secured to the pulley frame f; and instead of
connecting the upper ends of the chains g, g to the ends of the pulley frame the
said chains may be connected to other parts of the pulley frame. In some cases the
straps or frame ƒ may be omitted and the chains 9, 9 carrying the hook e be sus-
pended from the pin or axis 62 of the pulley b. We prefer however to carry our
invention into effect by the arrangement of parts represented in the drawing.
The suspending hook i of the differential or top pulley a is connected to the said
pulley by a chain or flexible connection in the following way: k is the cross head or
frame carrying the suspending hook i to the forked ends of which frame the upper
ends of the chains ll (or other flexible or jointed connections) are pinned or jointed
the lower ends of the said chains 1, 7 being engaged with the eyes m, m fixed to the
axis a² of the differential pulley a as represented.
By the use of a chain or flexible or jointed connection between the hook (or its
substitute) of the hottom block and the frame or axis of the said bottom block and
between the suspending hook (or its substitute) and the top or differential pulley
block the advantages hereinbefore pointed out are secured.
The flexible or jointed connections which may be used in place of chains may
consist of wire ropes or of hempen or other fibrous ropes or of jointed links but we
prefer to use chains as the flexible connections as described and represented.
Having now particularly described and ascertained the nature of our inven-
tion and the manner in which the same is to be performed we declare that we claim
as our invention of "Improvements in Differential Pulley Blocks"
-
First-Connecting the hook, or substitute for the hook, on which the load is
placed to the bottom pulley block by means of a chain or other flexible or jointed
connection for the purpose and substantially as herein before described and illustrated
in the accompanying drawing.
Secondly-Connecting the suspending hook or substitute for the hook of the
differential pulley block to the top block by a chain or other flexible or jointed
connection for the purpose and substantially as hereinbefore described and illustrated
in the accompanying drawing.
Dated the 25th day of September 1890.
GEORGE TANGIE.
JOHN NICHOLAS FLOYD.