IMPROVEMENTS IN THE TRANSMISSION OF POWER BY ENDLESS BELTS OF ROPE OR OTHER TENSILE LINES AND IN APPLIANCES CONNECTED THEREWITH
Year: 1882

page_text: PROVISIONAL SPECIFICATION left by James Thomson at the Office of the
Commissioners of Patents on the 9th March 1882.
JAMES THOMSON of Glasgow in the County of Lanark, North Britain Doctor of
Laws and Professor of Civil Engineering and Mechanics in the University of
Glasgow, "IMPROVEMENTS IN THE TRANSMISSION OF POWER BY ENDLESS BELTS
OF ROPE OR OTHER TENSILE LINES AND IN APPLIANCES CONNECTED THEREWITH."
The Improvements relate to the transmission of power from one revolving
drum, or other like revolving object, to another by methods somewhat resembling
but different from those of multiple endless ropes or cords connecting multiply-
grooved drums at present commonly in use. Instead of having the tensile line of
rope, cord, or other elongated tensile material, which for brevity I call the string,
merely to lap round part of the circumference of a groove in one drum and part of
the circumference of a groove in the other drum in its entire circuit, the string in a
circuit along itself from any point of itself round to the same again is made to lap
alternately round part of the circumference of a groove in one drum, and part of
the circumference of a groove in the other drum, this alternation being repeated
several times.
One way for carrying out this part of the Invention is to conduct the string
from a starting point say on groove 1, of drum A to groove 2 of drum B; thence
to groove 3 of drum A; thence to groove 4, of B; thence to groove 5, of A, and so
on, leaving alternate grooves occupied and vacant till a sufficient number of them
have been passed by the string coiling round while advancing in one way here
intended to be designated as forward in respect to the axes of rotation of the drums,
and thence to conduct the string gradually back to the starting point by coiling
alternately from groove of one drum to groove of the other drum these grooves
being those that were left vacant during the coiling with the forward advance in
respect to the axes of rotation of the drums.-The string in closing its circuit at
the starting point is continuously in tensile union with its continuation past that
point. Other varieties of arrangements for leading the circuit back to its closing
at the point referred to as the starting point, are possible, but the one here
particularized is simple and good,

page_text: For helping to maintain a proper tightness of the string, the string may be led
aside by one or more pulleys or drums adjustable so as to take up the slack: and
in some cases such additional pulleys may be used for leading back the string in
circuit to a starting point without the method already mentioned of leading it back
by grooves left vacant in the advance coiling part of the circuit.
Another part of the Invention consists in using anti-friction wheels or rollers
resembling those well known in Attwood's Machine in connection with the
multiply-coiled circuit of string, the use of the rollers being to abate the loss of
power in axle or journal friction liable to be caused through the pull of the multiple
lines of string.
Another part of the Invention consists in using for the multiply-coiled band,
steel wire or other metallic wire, spliced so as to close the circuit.
And another part of the Invention consists in using a continuous circuit of wire
manufactured as an endless ring without requiring a splice or other special junction
to close the circuit.