Figs. 3, 4, and 5 illustrate some of the applications of the electric
stop motion in connection with cotton machinery. The merit of this
invention lies in simplifying the means by which machinery may be
stopped automatically the instant, its work, from accident or otherwise,
begins to be improperly done. The use of electricity for this purpose
is made possible by the fact that comparatively dry cotton is a
nonconductor of electricity. In the process of carding, drawing or
spinning, the cotton is made to pass between rollers or other pieces
forming parts of an electric circuit. So long as the machine is properly
fed and in proper working condition, the stopping apparatus rests;
the moment the continuity of the cotton is broken or any irregularity
occurs, electric contact results, completing the circuit and causing an
electro magnet to act upon a lever or other device, and the machine is
stopped. The current is supplied by a small magneto-electric machine
driven by a band from the main driving shaft, and is always available
while the engine is running.
Fig. 3 shows the general arrangement of the apparatus as applied to a
drawing frame. In the process of drawing down the roll of cotton--the
sliver--four things may happen making it necessary to stop the machine.
A sliver may break on the way from the can to the drawing rollers,
or the supply of cotton may become exhausted; the cotton may lap or
accumulate on the drawing rollers; the sliver may break between the
drawing rollers and the calender rollers; or the front can may overflow.
In each and all of these cases the electric circuit is instantly
completed; the parts between which the cotton flows either come
together, as when breakage occurs, or, if there is lapping, they are
separated so as to make contact above. In any case, the current causes
the electro-magnet, S, against the side of the machine to move its
armature and set the stop motion in play.
Figs. 4 and 5 represent in detail the manner in which electric
connection is made in two cases requiring the intervention of the stop
motion. In Fig. 4 the upper part of a receiving can is shown. When
the can is full the cotton lifts the tube wheel, J, until it makes an
electrical connection, and the stop motion is brought into instant
action. In Fig. 5, the traction upon the yarn holds the hook borne by
the spring, F, away from G, and the electric circuit is interrupted. A
breakage of the yarn allows this spring to act; contact is made, and the
stop motion operates as before.
This simple and efficient device is exhibited by Howard & Bullough &
Riley, of Boston.