IMPROVEMENTS IN LOOMS
Year: 1877

page_text: PROVISIONAL SPECIFICATION left by John Marsden at the Office of the
Commissioners of Patents on the 7th September 1877.
JOHN MARSDEN, of Halifax, in the County of York.
FOR WEAVING."
"IMPROVEMENTS IN LOOMS
This Invention has for its object improvements in looms for weaving, and the
improvements relate mainly to looms in which the shuttle boxes are ranged in two
vertical tiers, a front and a back tier at each end of the batten, as described in the
Specifications of former Patents granted to me, and another in the year 1875,
No. 790 and No. 1349.
According to my present Invention I form the sley or lathe bottom with a rect-
angular frame, horizontal or nearly so, at each end of it; these frames are secured
to the sley swords. Across both the inner and outer end of each frame is a rod;
upon these rods slides a vertical frame, within which is received the set of shuttle
boxes, which can rise and fall in the frame.
The vertical frame can be moved to and fro along the rods by means of levers
carried by the swords and actuated by cams to bring either the front or back series
of shuttle boxes in a line with the shuttle race.
The bottom of the sets of shuttle boxes rests on a roller at the upper end of a
frame, which moves to and fro with the swords, and which can be raised or lowered
to bring any one or other of the series to the same elevation as the shuttle race, and
the sets of shuttle boxes are drawn downwards against the roller by springs. The
stem of the frame at its lower end is jointed to a long lever arm, counterbalanced
to sustain the boxes; this long lever arm carries a toothed rack with a space
between two teeth for each of the shuttle boxes in the vertical tiers, and also at the
back of these teeth a plate, against which a friction pad is drawn to restrain the
movement of the lever arm and prevent the shuttle boxes from rising or falling of
themselves. When the lever arm has been turned on its axis, as herein-after
described, to the extent requisite to bring any one or other of the shuttle boxes to
the same elevation as the shuttle race, a small wheel carried by a lever is by a
spring attached to this lever, caused to enter one of the spaces between the teeth,
and lock the long lever arm in the position to which it has been brought. At the same
[Price 4d77

page_text: time the friction break, which presses on the plate carried by the long lever arm, is
put out of action to allow the whole weight of the shuttle boxes to be supported by
the small wheel.
The lever which carries the friction pad is for this purpose coupled by a strong
spring to the lever carrying the small wheel, and is also coupled to it by a link,
and where the link is coupled to one or other lever, a slot is formed so that the
lever carrying the wheel may move a certain distance without removing the break,
but so that when the wheel has entered between the teeth on the long lever arm,
the break is taken off and the small wheel is left to lock and hold the shuttle boxes
at the required elevation, by which great accuracy is obtained in bringing the
shuttle boxes to the correct level.
At the times when the shuttle boxes may have again to be raised or lowered, the
lever carrying the small wheel before mentioned is forced back by a rod acted on
by a cam, and so the wheel is disengaged from the rack teeth on the long lever arm,
which supports the shuttle boxes; the friction break before mentioned then again
comes into action and restrains the boxes from rising or falling of themselves.
The cams for bringing either the front or back series of shuttle boxes in a line
with the shuttle race are mounted on studs on the sley swords, and have a pin wheel
attached to them, the pins of which can be brought against and acted upon by a
driver at each forward movement of the sley.
The driver is ordinarily held up out of the way of the pins by a catch, which
catch is withdrawn by the jacquard whenever a change in position of the front and
back series of shuttle boxes is required.
When cither the front or back series has been brought in a line with the
shuttle race they are retained by a curved lever forced by a spring against two of
the pins on the pin wheel.
To raise or lower the long lever arm which raises or lowers the shuttle boxes so
as to bring either one or other of the shuttle boxes in a line with the shuttle race,
the lever arm is coupled by a rod to a vertical slide, through which are formed as
many holes as there are shuttle boxes in each vertical tier; the holes are at
different heights in the slide, and each hole is fitted with a peg, any one or
other of which can be thrust forward and caused to protrude from the face of
the slide.
In front of the face of the slide two rods work up and down in opposite direc-
tions; they each have secured to them a horizontal presser bar. The movement
of the rods causes the presser bars alternately to move towards and recede from one
another. When one of the pegs has been protruded from the face of the slide
the presser bars more together and act upon the upper and under sides of
whichever peg has been thrust forward, and so move the slide, and consequently
the series of shuttle boxes from one level to another, according to whichever peg has
been thrust forward.
The pegs might be in a horizontal line, and the presser bars be made in steps to
obtain the same result.
In order that the shuttle boxes may be moved quietly from one elevation
to another, the rod which connects the vertical slide to the long lever arm that
raises and lowers the shuttle boxes is passed through a spring friction clip.
Various means for thrusting the pegs forward at the times required may be
adopted.
The arrangement I employ is as follows:-The pegs are not vertically one below
the other, but form a line about at an angle of 45°, and the rear end of each peg is
coupled to a lever arm carried by a rocking shaft. There is a separate shaft and
arm for each peg, and the shafts are one below the others like the pegs. At right
angles to these arms are other shorter arms acted upon, from time to time, by a
notched slide. Whenever the slide and shuttle boxes have been shifted, as above
described, to any desired elevation, the notched slide descends and comes against
the short crank arms, and draws back the peg which has been protruded. Each of
the rocking shafts has also another right-angled lever fast upon it; one arm of this

page_text: lever abuts at its end against a lever catch which is in connection with the jac-
quard, the other arm is coupled by a spring to the lever catch.
When any one or other of the lever catches is lifted by the jacquard, the rocking
shaft, which is then set free, is turned by its spring, and one of the pegs is thrust
forward. The presser bars then act upon this peg and hold it between them;
afterwards, when the shuttle boxes have been locked in position, as before described,
the peg is withdrawn as explained, and the rocking shaft which works it is again
secured by the catch which is in connection with the jacquard. Each of the
lever catches may either have a single cord or more passing from it to the jac-
quard.
The movement of the two rods of the presser bars is effected as follows:-The
two rods are side by side, and they are connected to two bell cranks on two parallel
axes; the cranks are connected by a link, so that when one crank turns the other
turns with it, and one rod is raised whilst the other is lowered. One of the cranks
is rocked by a rod connected to it by a yielding connection to avoid breakage in
case of two pins being thrust forward in error; the rod descends to a lever acted
upon by a cam on an axis which revolves at the same speed as the cam from which
the picking motion is derived.
The arrangement herein-before described for shifting vertical tiers of shuttle
boxes is applicable not only for working double tiers of boxes, as described, but
also for working single tiers of boxes.
In order to prevent breakage in case the shuttle when thrown across the
shuttle race does not properly enter the box into which it is thrown, I arrange the
weft detectors or forks in such manner that if they cannot descend by reason of
their being obstructed by a shuttle lying below them, a projection on the lever
forks or detectors shall on the forward movement of the sley come in contact with
part of the stop motion and stop the loom.