IMPROVEMENTS IN DRIVING STRAPS AND CORDS
Year: 1877

page_text: LETTERS PATENT to Gerard Wenzeslaus von Nawrocki, of the Firm of J. Brandt
and G. W. v. Nawrocki, of Berlin, Germany, Patent Agents, for the Invention
of "IMPROVEMENTS IN DRIVING STRAPS AND CORDS."
from Otto Köhsel and Sohn, of Hanover, Germany.
A communication
PROVISIONAL SPECIFICATION left by the said Gerard Wenzeslaus von
Nawrocki at the Office of the Commissioners of Patents on the 5th September
1877.
GERARD WENZESLAUS VON NAWROCKI, of the Firm of J. Brandt and G. W. v.
Nawrocki, of Berlin, Germany, Patent Agents. "IMPROVEMENTS IN DRIVING
STRAPS AND CORDS." (A communication from Otto Köhsel and Sohn, of Hanover,
Germany.)
Leather belting, india-rubber belting, combined with textile fabrics and woven
hemp belting or driving straps, have not altogether satisfied the requirements,
inasmuch as they gradually stretch so as at last to slip, and thus fail to transmit
the required power. When tightened up or shortened they stretch again to the
utmost limit of their strength and break at last. Neither have the hair belts lately
introduced proved altogether satisfactory, because the edges wear off immediately
when thrown from a loose to a fast pulley.
The object of this Invention is to overcome the aforesaid evils. For this purpose
iron or other metal ropes, consisting of thin wires covered, doubled, or spun over
with hemp or other thread, are combined with hemp or other woven fabric so as
to form bands or cords; or thin metal bars or strips may be used instead of the
aforesaid wires or ropes. Before being applied to this purpose they are softened in
the fire.
According to the width or size of the belt or cord more or less of such ropes
[Price Rd 1

page_text: strands, wires, or strips, are woven or inserted in the textile fabric, which may be
woven either plain, or ribbed or corded.
The bands or cords may be manufactured with or without impregnation of varnish
or other suitable substances; they may be coated with gutta percha or india-rubber,
or be impregnated therewith.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Gerard Wenzeslaus von Nawrocki in the Great Seal Patent Office on
the 5th March 1878.
"
GERARD WENZESLAUS VON NAWROCKI, of the Firm of J. Brandt and G. W. v.
Nawrocki, of Berlin, Germany, Patent Agents. IMPROVEMENTS IN DRIVING
STRAPS AND CORDS." (A communication from Otto Köhsel and Sohn, of Hanover,
Germany.)
Leather belting, india-rubber belting, combined with textile fabrics and woven
hemp belting or driving straps, have not altogether satisfied the requirements,
inasmuch as they gradually stretch so as at last to slip, and thus fail to transmit the
required power. When tightened up or shortened they stretch again to the utmost
limit of their strength and break at last. Neither have the hair belts lately
introduced proved altogether satisfactory, because the edges wear off immediately
when thrown from a loose to a fast pulley.
The object of this Invention is to overcome the aforesaid evils. For this purpose
iron or other metal ropes consisting of thin wires covered, doubled, or spun over
with hemp or other thread, are combined with hemp or other woven fabric so as to
form bands or cords; or thin metal bars or strips may be used instead of the afore-
said wires or ropes. Before being applied to this purpose they are softened in the
fire.
According to the width or size of the belt or cord more or less of such ropes,
strands, wires, or strips, are woven or inserted in the textile fabric, which may be
woven either plain, or ribbed or corded.
The bands or cords may be manufactured with or without impregnation of varnish
or other suitable substances; they may be coated with gutta percha or india-rubber,
or be impregnated therewith.
And in order that this Invention may be more fully understood I will now describe
Drawings illustrating the same. Figure 1 shews the upper and Figure 2 the lower
side of a belt made according to this Invention; Figures 3 and 4 are similar and
corresponding views, but drawn to a larger scale; Figure 5 is an enlarged cross
section, and Figure 6 a side view of the same.
a, a, are the wire ropes or strands, having the wires covered or spun over, as
described; these ropes are placed within the hemp or other cords b, b, and c, c,
woven or platted around them.
The belt thus consists of a combination of several or many longitudinal wire ropes
which are ultimately united by weft and warp of hemp or other textile fabric,
coated or impregnated, or not, as aforesaid. These driving belts or straps are much

page_text: stronger than those which consist of animal products or of textile fabrics without
any inherent strength. These straps are also homogeneous and of equal strength
every where (whereas leather straps by the greatest care in the manufacture present
inequalities in thickness and strength); the improved straps therefore also run
evenly on the pulleys. They are also more durable, and cannot stretch appreciably.
They are also cheaper than leather belting.
The evenness and regularity of the transmission of power by the improved straps
render them especially advantageous in certain trades, such as silk manufacture, as
they do not slip; their efficiency is also greater than other straps.
And having thus described and ascertained the nature of this Invention, I
declare that I claim, as the aforesaid communicated Invention, constructing driving
bands of textile fabric with inlaid ropes or strands of thin wire or metallic strips, as
set forth.
In witness whereof, I, the said Gerard Wenzeslaus von Nawrocki, have here-
unto set my hand and seal, this First day of March, in the year of our
our Lord One thousand eight hundred and seventy-eight.
GERARD WENZESLAUS v. NAWROCKL (L.S.)