An Improved Grip for Cords or Ropes.
Year: 1892

page_text: Date of Application, 29th Sept., 1892
Complete Specification Left, 29th July, 1893-Accepted, 2nd Sept., 1893
PROVISIONAL SPECIFICATION.
An Improved Grip for Cords or Ropes.
We, JOHN HARRISON and JOHN BROWN, of The Harrison Patents Company,
Limited, both of Lincolnshire Iron Works, Stamford, in the County of Lincoln,
Engineers, do hereby declare the nature of this invention to be as follows:-
This invention relates to an improved grip or gripping apparatus for use in
connection with pulleys employed in raising and lowering weights by means of a
cord or rope or otherwise.
In carrying out the invention as applied to a pulley over which a cord passes in
the ordinary manner, we mount in connection with the frame carrying the ordinary
pulley two toothed segments between which the rope passes, the adjacent faces of
the said segments being so grooved that when the segments are in one position the
rope will pass freely between them whilst in another position they will grip it.
With this arrangement the rope passes freely between the toothed segments in one
direction but when running in the other direction the tendency is to move them
to grip the rope.
In order to prevent such gripping taking place when releasing
the load we attach to one of the segments a pull for keeping the segments in such
a position that the rope can pass freely.
On one of the segments is also fixed a stirrup through which one end of the rope
passes and which serves as a guide and a balance weight causing the segments to
close upon and grip the rope quickly. Instead of a balance weight a spring may
be used.
When it is required to hold the rope in two directions we use wheels instead of
segments and form the grooves in opposite ways and throw either set of grooves in
action by a rope or hand lever..
Dated this 29th day of September 1892.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicants.
COMPLETE SPECIFICATION.
An Improved Grip for Cords or Ropes.
We, JOHN HARRISON and JOHN BROWN of The Harrison Patents Company,
Limited, both of Lincolnshire Iron Works, Stamford, in the County of Lincoln,
Engineers, do hereby declare the nature of this invention and in what manner
the same is to be performed, to be particularly described and ascertained in
and by the following statement :-
This invention relates to an improved grip or gripping apparatus for use in
connection with pulley blocks employed in raising and lowering weights by means
of a cord or rope or otherwise.
In carrying out the invention as applied to a pulley over which a cord passes
in the ordinary manner, we mount in connection with the frame carrying the pulley
two toothed segments between which the rope passes, the adjacent faces of the
said segments being so grooved that when the segments are in one position the rope
will pass freely between them whilst in another position they will grip it. With
this arrangement the rope passes freely between the toothed segments in one
direction but when running in the other direction the tendency is to move them to

page_text: grip the rope.
In order to prevent such gripping taking place when releasing the
load we attach to one of the segments a pull for keeping the segments in such a
position that the rope can pass freely.
On one of the segments is also fixed a stirrup through which one end of the
rope passes and which serves as a guide and a balance weight causing the segments
to close upon and grip the rope quickly. Instead of a balance weight a spring may
be used.
To enable our invention to be fully understood we will describe how it can
be carried into practice by reference to the accompanying drawings, in which :-
Figure 1 is a side elevation of a rope pulley-block having gripping apparatus
constructed according to our invention applied thereto.
Figure 2 is a view taken at a right angle to Figure 1.
Figure 3 is a horizontal section on the line 3-3, Figure 1.
Figure 4 is a view of a detail.
Figures 5 and 6 are a side elevation and a sectional plan respectively illustrating 1
a modification.
Referring to Figures 1 to 3 a and b are the two segments between which the
rope c passes, the said segments being pivotted upon pins d, e respectively, carried
in the framing f. f is the pulley. The segments a and b are toothed so that by
gearing with one another they will move together to grip the rope equally, the
segment a being provided with a weighted extension g which causes the segments
to exert the gripping action, the said extension being in the form of a stirrup and
serving as a guide for the rope.
h, h are the grooves in the adjacent faces of the segments a, b which grooves
gradually decrease in depth and width towards the lower ends of the said
segments as shewn respectively in Figures 1 and 4, the latter figure shewing
the face of one of the segments.
By this arrangement assuming that the part of the rope passing through the
extension g to have a load to be lifted it will be seen that when that part of
the rope passing between the segments is pulled it will pass freely between the
segments, as it tends by reason of its friction with the segments to move the
same to present portions of their grooves of greater width and depth to the rope.
The tendency of the rope to run back when the pull is relieved will be prevented
by the friction of the rope against the segments tending to move them to present
portions of their grooves of less width and depth to the rope, thereby gripping
the same.
In order to prevent the segments gripping the rope when it is required to release
or let the load run down we provide the attachment i to the segment a to which
attachment a cord j is fastened so that by pulling the said cord the segments will
be lifted and allow the rope to pass freely between them.
When it is required to hold the rope in two directions we may use wheels instead
of segments and form the grooves in opposite ways and throw either set of grooves
in action by a rope or hand lever.
In the modification shewn in Figures 5 and 6 one only of the segments is used
it being arranged to grip the rope by bearing towards the pulley f'. The said
segment is provided with stops i, i which allow it a certain amount of play in order
to move to grip the rope tighter when the pull is relieved.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1. The combination with a pulley-block of a grooved segment or segments
adapted to engage the rope passing round the pulley the said segment or segments
being constructed and operating in such a manner as to allow the movement of the
rope in one direction but preventing its movement in the opposite direction,
substantially as described.

page_text: 2. The improved gripping devices for use in connection with pulley blocks
herein before described and represented in Figures 1 to 4 and in Figures 5 and 6
of the accompanying drawings.
Dated the 29th day of July 1893.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicants.