IMPROVEMENTS IN SHUTTLES FOR LOOMS
Year: 1878

page_text: PROVISIONAL SPECIFICATION left by Alexander Melville Clark at the Office
of the Commissioners of Patents on the 8th May 1878. A communication
from abroad by William Alexander Doherty and John McHugh, both of Fall
River, in the County of Bristol, State of Rhode Island, United States of
America.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent. "IMPROVEMENTS IN SHUTTLES FOR LOOMS." [A communication
from abroad by William Alexander Doherty and John MoHugh, both of Fall River,
in the County of Bristol, State of Rhode Island, United States of America.]
The object of this Invention is to furnish an attachment to right and left hand
loom shuttles, by which the weaving of floats in the cloth is prevented by means of
a guard device that is released and thrown over the point of the spindle in case a
false shed is made by any irregularities in the warp, or by the presence of extraneous
matter or other obstructing causes, so that a part of the warp threads is carried
lower than usual.
The device interrupts the drawing out the filling thread from the shuttle and
breaks the same, and stops thereby the loom by the usual automatic stop motion of
the same.
The Invention consists of a lateral spring guard that swings on a fixed cross pin
or screw extending across the shuttle below the point of the spindle, and is secured
to a side spring of the shuttle, which spring projects beyond the upper edge of the
shell, and is acted upon by a false shed that releases it and throws it over the
spindle point so as to break the filling thread.
The guard is preferably bent in the shape of a semicircle or bow in one con-
tinuous piece, with end coils by which it swings on the stationary cross pin, and is
bent at one end so as to form a toe piece that bears on a seat of the shuttle and
exerts a spring pressure on the guard, while a looped arm at the opposite end of the
guard engages a hook of the side spring of the shuttle. When the looped arm of
the guard is hooked to the retaining side spring the guard is swung down below
the point of the spindle and retained in this position until it is carried over the
point of the spindle, when the side spring releases the guard device by the pressure

page_text: of the warp threads exerted thereon. The guard has also a central downwardly
bent finger rest that facilitates the setting of the guard device into its proper position
on the hook of the side spring.
The side spring is like the guard spring made of one continuous wire, and coiled
at one end like a watch spring, which end is attached by a centre screw to the
shuttle, the side spring being placed in a longitudinal slit or recess of the shuttle at
that side which is in front of the reed and next to the weaver. The screw serves
to adjust the tension of the side spring, which may also be attached to the metal
plate that is then secured to the inside of the shuttle. The side spring is extended
back towards the butt end of the spindle, and arranged so that its middle part
projects above the edge of the shuttle, it being turned down and back at the opposite
end so as to form a look, the end back of the hook being hung to a pivot on which,
and on the tension screw, the side spring works. The outer end of the side spring
is guided along a staple which controls the extent of motion of the side spring and
prevents it from projecting beyond the required distance from the edge of the
shuttle. As the tension of the projecting spring may be regulated by the fastening
centre screw the device may be adjusted to a greater or less nicety, and the guard
released by a greater or less pressure of the warp threads on the spring, as a false
shed float or other obstruction presses the side spring down and releases the looped
arm of the guard so that the spring and toe throw the guard over the point of the
spindle below the filling thread which is flowing off at the point of the spindle,
causing it thereby to break and stop the loom by its automatic stop motion.
The guard attachment may be used for right and left hand shuttles by changing
the side spring and also the position of the guard from one side to the other.
For the purpose of simplifying the construction of the guard attachment the side
spring may be connected directly to an extension crank arm of the guard, the side
spring being at its coil portion permanently attached to the shuttle, and the tension
regulated by a toc piece or arm of the guard at the end opposite to the crank arm.
The arm runs nearly parallel to the guard, and forms contact when the guard is
thrown down into horizontal position with an adjustable tension screw that may be
raised or lowered in the shuttle so as to exert a greater or less pressure on the
tension arm of the guard and regulate thereby the tension of the side spring and
the pressure required by the warp threads for releasing the guard.
In this latter modified construction the guard is retained in position below the
spindle point simply by the action of the spring on the crank arm, which presses
the tension arm on the tension screw, the pressure of the warp threads on the side
spring carrying the spring and crank arm downward and below the fixed cross pin
so as to instantly release the guard and throw it by the full spring action of the
side spring over the point of the spindle, breaking the filling thread and stopping
the loom, as before described.