The principal object the inventors of the machine we illustrate herewith
had in view in designing it was to arrange a mode of working the grip
motion positively, so that the cloth shall be received freely and without
strain or friction before or up to the very instant at which each fold is
completed, and shall then be seized and firmly held. In existing machines
there is not we believe, any arrangement for the accomplishment of this
purpose; it is true, the table upon which the cloth is folded is relieved
at the termination of the stroke of the plaiting knife, but the upper
gripper bar, against which the folds of cloth are pressed upon the return
of the table to its normal position, is stationary, being rigidly fixed
to the sides of the machine. One result of this rigidity is that the
cloth has to be forcibly thrust by the plaiting knife under the upper
gripper bar, and in consequence of the violence involved the fold just
made at the opposite end is dragged out from the grip, making a short
fold, and further, in the case of delicate finishes, giving rise to
damaged goods. Another result of this arrangement, when the cloth is not
pressed against the upper bar, is that it returns with the return stroke
of the plaiting knife, the grip not being made until the knife is clear
of the upper bar; thus the plaits or folds are made of irregular length.
[Illustration: IMPROVED PLAITING MACHINE.]
To remedy this and to prevent its occurrence, Messrs. A. Edmeston and
Sons, Manchester, in the plaiting machines they are now manufacturing
make the upper gripper bar movable as well as the table below. Referring
to the illustration, the upper gripper bars, A A, are capable of moving
about the center pins, B B, and when the machine is working are operated
in the following manner:
Upon the shaft, C, which revolves in unison with the crank shaft working
the plaiting levers and knife, are placed two cams, D, one at each end,
inside the main frames. These cams engage with and work two escapement
levers or pallets, E E, upon which rest the feet of four rods, attached
one end to each of the upper gripper bars. Upon these four rods are
helical springs of sufficient strength to hold down, by means of the
grippers to which they are connected, the folds of cloth that have just
been made. The cam, D, is so shaped that when the advancing plaiting
knife and cloth reach the front edge of the gripper bar, the gripper is
raised from the table to admit them freely. The instant the end of the
stroke is reached the anchor pallet or lever, E, escapes from the cam,
and the gripper bar is suddenly forced on to the knife and cloth by the
springs before mentioned, securely retaining the piece in its position.
Simultaneously with the first of these motions the plaiting table itself
is lowered, and, when the plaiting knife reaches the end of its stroke,
is released by means of the levers and chains, F F, which are in
connection with the escapement pallets, E, and partake of their every
motion. These chains are so attached that they exert no effort upon the
table until the escapement lever is moved, thus permitting the plaiting
table to press upward against either one or both of the gripper bars with
the full force imparted to it by the weights and levers, G¹ G¹. The
chains, furthermore, are also threaded over pulleys in such a manner that
they adjust themselves automatically to every position of the table and
to the different thicknesses which the folded cloth acquires.
It will be obvious from this description that in plaiting there is no
more strain put upon the cloth in placing it under the grip than is
necessary to draw it over the table from the feed rollers. This feature
insures perfect immunity from the dragging out of grip, as already
described, and renders the machine very useful for finishers and
makers-up, as the delicacy with which the cloth is handled prevents any
damage being done to the finish of the lightest fabrics. Double cloth
can, of course, be plaited by it equally well, and the precision and
uniformity with which the cloth is plaited makes the machine thoroughly
reliable as a cloth measurer.--_Tex. Manfr._
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