Improved Means for Regulating Warp Tension in Looms.
Year: 1889

page_text: Date of Application, 22nd June, 1889-Accepted, 21st June, 1890
COMPLETE SPECIFICATION.
Improved Means for Regulating Warp Tension in Looms.
I, OSWALD HOFFMANN, of Neugersdorf, Saxony, Germany, Gentleman, do hereby
declare the nature of this invention and in what manner the same is to be
performed to be particularly described and ascertained in and by the following
statement:-
To prevent, in linen weaving, the formation of reed-stripes, the loom is usually
arranged in such a manner that when the shed is shut, the eyes of the heddles are
situated underneath the plane of the breast beam and cloth-beam and that the beating
of the latho takes place when the shed commences to open for the next pick.
By this arrangement, the tension of the warp is distributed during the formation
of the shed in an irregular manner on the two sheds. This irregular distribution
of the tension renders the weaving during the formation of the shed more difficult,
but takes place substantially at the beating of the lathe on the fabric in such a manner
that the formation of stripes resulting from the reeds is prevented.
My invention has for its object to produce this difference of tension of the warp
and in consequence a fabric without reed stripes, by the oscillating motion of a
leasing rail. This is done in such a manner, that the difference of tension is greatest
at the moment of the heating of the lathe, and that the tension of the warp is a
uniform ono when the shed is open.
The arrangement of the device is shewn in the annexed drawings.
One of the leasing rails, for instance, the rail a situated near the lath supporting
the warp (see Fig. 1) and carried by the arms of so as to be capable of moving
round g, has imparted to it by an eccentric e fixed upon a shaft d, an up and
down oscillating motion in such a manner, that at each beating of the lathe
alternately one part of the warp is stretched and at the same time the other
loosened.
When the shed is open, the tension of the warp is uniformly distributed on the
two sheds owing to the rail a being then in its middle position.
To prevent the effect of the movement of one of the leasing rails (a) being
diminished by the other rail (b) when also put in motion, the latter is fastened
either on the side of the frame or to a rod c arranged underneath the rail.
The parts actuating the rail may be variously arranged according to the particular
construction of loom to which my invention is applied.
The eccentric may be applied to another shaft and the motion may be transmitted
to the leasing rail by the intermediary of a shaft and levers.
In lieu of imparting oscillating motion to only one leasing rail, the two rails a and b
(see Fig. 2) may be connected together and be both actuated by an eccentric so that
one of the rails ascends while the other descends and vice versa.
The pair of leasing rails may be supported either in a movable manner so that
the rails move round a point m, or the rails may swing freely without being supported
by a fixed rod.
In place of the leasing rails, special rods similarly dividing the warp may be given
an oscillating motion. For other fabrics than linen more than two leasing rails may
be employed which at the moment of the beating of the lathe are alternately moved by
eccentrics and stretch corresponding parts of the warp.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what 1
claim is :

page_text: oscillating leasing rails or similar rods correspondingly dividing the warp at the point
of intersection of the fabric for the purpose of giving different tensions to the two
portions of the warp at the moment of the beating of the lathe, and uniform tensions
while the shed is open, and for preventing the formation of stripes resulting
from the reeds, substantially as
set forth and shewn in the accompanying
drawings.
Dated this 22nd day of Tunn 1000
OSWALD HOFFMANN,
Per L. W.