Improvements in the Untwisting of Waste Rope, Twine, and the like.
Year: 1891

page_text: COMPLETE SPECIFICATION.
Improvements in the Untwisting of Waste Rope, Twine, and the like.
A communication from CARL BERGMANN, of Meissen, Saxony, in the German
Empire, Engineer.
I, ALFRED JULIUS BOULT, of 323, High Holborn, in the County of Middlesex
M.I.M.E., 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 consists of a process of untwisting waste rope, lengths of cables,
strings and cords, with a view to making the material obtained serviceable again
for the manufacture of the new article; and of mechanism adapted for carrying out
such process.
Waste rope has hitherto been generally "picked" or untwisted by hand. For
this purpose the strands had first to be singled out at one end of the piece of rope
and then unwound by slow degrees and each strand was then by a similar
process
divided into threads. The drawbacks of such a method are obvious; In the first
place it is exceedingly tedious and secondly the quantity of valuable material it
yields is quite out of proportion with the time employed in its production. Lastly
the handling of the very brittle fibres is conducive to considerable loss, as a great
part of them are unavoidably broken in the process of "picking" and thus made
worthless for subsequent use. To remedy these inconveniences the mechanism
hereinafter described has been devised, which enables the untwisting operation to
be carried out in a simple and efficient manner in much less time and with far more
satisfactory results than those obtainable by hand-labour.
The principle of this new mechanical process is as follows:-
The waste rope to be reduced to the condition of spinning material is first cut up
into pieces of suitable length. Each length of rope is then first untwisted somewhat
by hand, at both ends, so that the strands may be spread out flat side by side.
Both ends are then inserted into gripping devices preferably of an arrangement to
be described further on. One of these gripping devices is preferably stationary,
while the other is adapted to revolve in the direction opposite to that in which the
rope was originally wound. The length of rope between the two devices is kept
taut provision being made to make up for its extension in length as it is untwisted.
The revolving gripper is allowed to continue in motion until all the strands of
the rope lie parallel to each other throughout their length and are stretched out
in spite of their tendency to resume a spiral form. In removing the strands from
the grippers they are submitted to an additional stretching action and thereby finally
freed from the tendency to shrink back into their twisted form. Instead of
employing one stationary gripper both grippers may of course be made capable of
rotating in opposite directions. By these means the piece of rope is untwisted
throughout its length simultaneously and not gradually as in the case of manual
labour.
Each strand may then by a similar process be divided into threads without the
fibres of which they are composed sustaining the least damage.
In
One form of gripper which is deemed particularly suitable for the purpose
indicated is shown in Figs. 1 to 3 of the accompanying drawing. The untwisted
and spread rope end is placed upon a corrugated or roughened surface a.
suitable lugs attached to the supporting surface is secured a spindle about which is
adapted to swing a pressure plate a'. This plate terminates in yielding fingers a³ a*
adapted to hold down the strands of the rope upon the surface a and subjected to
the pressure of a spring a³ acting upon the pressure plate a'.
This gripping device offers this peculiarity that though the pressure of the

page_text: an equal amount of power each of these fingers being capable of yielding indepen-
dently of the others will fit the thickness of the strand or thread it holds and
securely grip the same no matter how thick or thin it may be. Thus the gripping
of the pieces of rope is always perfectly secure even where the strands of which it
is composed are not of uniform thickness. From the arrangement described arises
the further advantage that when the untwisting is completed the strands or threads
may be removed from the gripping mechanism singly whereby they are prevented
from getting twisted together or entangled as soon as they are released from the
grippers, as they are apt to do when released all at once, thus rendering the work
done practically useless.
In the drawings
Figures 1 & 2 represent a length of rope placed in the gripping mechanism
respectively before and after the untwisting operation. The mode of action of the
spring-controlled fingers a² is clearly illustrated by Figures 2 & 3.
Figures 4 to 6 represent a suitable form of a complete waste rope untwisting
machine,
Figure 4 being a side view,
Figure 5 a plan, and
Figure 6 a cross section of the same.
In this machine the length of rope to be untwisted is stretched as before stated
between two gripping devices one of which is adapted to receive rotary motion from
any suitable source and at the same time is provided with a brake arrangement
which when the gripper is stopped is to retain it firmly in position so as to prevent
it from being rotated in the opposite direction by the strands tending to roll up
again. The other gripper which is stationary rests upon a support or carriage
which under the action of a weight continually stretches the length of rope as it
becomes more and more capable of extension in the act of untwisting.
A. A are the gripping devices. A' is secured to a spindle b carrying loose and
fast pulleys by which through the medium of a suitable driving belt the
spindle band with it the gripper A is revolved. In the supporting frame or head-
stock of the spindle is arranged a rod c which carries a strap-guide c' and a brake
block or shoe. By operating the treadled the strap-guide or fork c¹ acted upon
through the medium of the links d d² and d³ is caused to pass the strap on to the
fast pulley thereby setting the spindle in motion.
с
By releasing the treadle the spring e is allowed to move the links d' d² d³ back
into their position of rest and the strap is passed by the guide fork c¹ upon the loose
pulley with the result that the brake c² will press upon a disc 63 mounted upon
the spindle thus preventing any backward rotation or twisting of the strands
of rope.
The stationary gripper A is supported by the carriage f sliding on ways f' and
acted upon by a weight g which causes it to keep the rope and strands as the
untwisting progresses in a tight condition. When the treadle h is depressed the
links will force a brake-block against the carriage f which is thus locked
in the ways f¹ when it is desired to remove the strand or threads of the untwisted
rope.
The mode of operation of the machine has, however, been made sufficiently clear
by the foregoing description of the process. Modifications in the details of
construction may naturally be made without departing from the principle of the
invention.
Having now particularly described and ascertained the nature of the said
invention, as communicated to me by my foreign correspondent, and in what manner
the same is to be performed, I declare that what I claim is :-
I. The process of untwisting waste rope cord or the like consisting in first cutting
up the rope to be operated upon into suitable lengths and securing by hand both
ends of each length of rope into gripping devices one of which is capable of rotary

page_text: motion in the direction opposite to that of the original twist of the rope while the
other is stationary or both of which may be adapted to rotate in opposite directions
the result in each case being the untwisting or unrolling of the strands or threads
of which the rope is composed and the parallel stretching of such strands or
threads.
II. In a machine for untwisting rope cord or the like a gripping device for
holding the untwisted ends or strands of ropes cords or the like in which each strand
or thread is singly held by yielding fingers such as a² integral or connected with
the main spring-controlled body which under the action of the spring causes them
tightly to grip their respective ends of strands or threads substantially as described
and illustrated in the accompanying drawings.
III. A machine for untwisting rope cord or the like in which the length or strand
of rope cord or the like is held by gripping devices such as are mentioned in the
preceding claim one of which gripping devices is adapted to be rotated and to be
fixed when at rest by means of a brake to prevent the divided strands from twisting
together again while the other or non-rotating gripping device is arranged upon a
slide or carriage adapted to recede by the action of a weight or equivalent to make
up for the increasing length of strands or threads as they are unwound substantially
as described and illustrated in the accompanying drawings.
IV. The arrangement and combination of parts constituting the complete machine
for untwisting rope cord or the like substantially as described and illustrated in the
accompanying drawings.
Dated this 11th day of March 1801
W. P. THOMPSON & BOULT,
Agents for the Applicant.