Improvements in and relating to the Shedding Motions of Looms.
Year: 1893

page_text: Date of Application, 28th June, 1893-Accepted, 19th Aug., 1893
COMPLETE SPECIFICATION.
Improvements in and relating to the Shedding Motions of Looms.
We, LAW BULCOCK and WILL JOHN THRELFALL, of Springfield Mills, Burnley,
in the County of Lancaster, Manufacturers, 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 :-
Our invention relates firstly to mechanism for operating separate and distinct
healds or harness to form selvedges.
We make use of a rocking shaft mounted in and extending across the loom frame
in any desirable position, and deriving its rocking motion from a crank or the like
preferably fixed by a nut to the tappet shaft outside the tappet wheel of the loom,
and then connected by a connecting rod to an arm proceeding from the said
rocking shaft.
The healds or harness for operating the side ends are provided at their lower
staves with leather bands, which are then attached respectively to adjustable arms
or rocking levers on the rocking shaft.
In order to get a perpendicular and perfectly parallel lift, we pass the leather
bands over a loose boss or the like carried by a stud on a bracket secured to the
loom frame, when they are then caused to cross each other, and are attached
respectively to the aforesaid adjustable arms or rocking levers on the said rocking
shaft. It will be evident that whatever angular drag may be given to the leather
bands by the movement of the said arms or rocking levers, it will not be imparted
to the healds, as this is entirely got rid of by the crossing of the leather bands on
each side of the loose boss or the like, a perfectly true up and down motion being
thereby obtained.
The connecting rod or the adjustable arm or arms attached to the rocking shaft
or the crank are either one or all provided with slots, and fastened together by
bolts and studs, so as to permit of a ready adjustment of the parts, for increasing or
decreasing the depth of the shed.
If desired, eccentrics or cams may be fixed to the rocking shaft instead of the
said arms or rocking levers, the leather bands being attached to any convenient
part of the circumference of such eccentrics or cams by set screws or other suitable
means.
In the accompanying drawings,
Fig. 1 is a sectional end elevation, and
Fig. 2 a front view of a loom with our improved shedding motion applied.
A is the rocking shaft, to which motion is imparted by means of a crank or the
like B, preferably fixed by a nut C on the tappet shaft D on the outside of the
tappet wheel E, and then connected by the connecting rod F to the arm G
proceeding from the said rocking shaft.
To the healds H for operating the warp threads are attached bands of leather or
similar material I, which are passed under the loose boss J mounted on the stud K
carried by the bracket L, and then crossed one on each side of the said loose boss,
and secured respectively to pins or studs M in slots N of the double armed lever O,
or two single levers or in case of twills three or four of such levers may be used.
The bracket L is firmly secured to the loom frame by bolts P (as seen in Fig. 2)
and is continued downwards, so as to serve as a stay piece for the rocking shaft A.
The usual head roller, bowls and straps at the top of the loom may be employed
as in plain weaving.
By the crossing of the bands of leather or like material under the loose boss
or the like J, and by the peculiar and novel arrangement of the parts for operating
our improved shedding motion, a perfectly perpendicular and parallel up and down

page_text: motion and a deep shed are obtained, with little liability to breakage or damage of
the warp threads.
but it
In weaving it is often required that one portion of the cloth shall be of twill or
other pattern, whilst another portion shall be of plain texture. Generally, a dobby
or like pattern operating mechanism has previous been used for this purpose,
will be apparent that by an arrangement of the arms or rocking levers or eccentrics
or cams on the said rocking shaft, we are enabled to accomplish this object without
the aid of dobbies or the like, or in like manner our invention may be employed for
operating the entire shedding motion of plain looms thereby dispensing with tappets
and treadles. In such cases, our improved shedding motion may be separate and
distinct from or in combination with the parts for operating selvedges as already
described.
For weaving a plain and twill fabric in one loom, the mechanism for operating
the healds for forming the plain portion of the fabric is constructed identically the
same as that described and illustrated in Figs. 1 and 2, the healds for forming the
plain portion of the fabric being separate and distinct from the healds which
produce the twill pattern. The latter may be operated by the mechanism
ordinarily in use for producing twills. For plain weaving, the usual tappets and
treadles may he dispensed with and the arrangement adopted as previously described
and illustrated.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is :-
1. The improved selvedge or shedding motion, substantially as described and
illustrated in Figs. 1 and 2.
2. The crank or the like B, rocking shaft A, connecting mechanism, loose boss J
and rocking arms or levers O or eccentrics or cams, substantially as described and
illustrated for the purpose specified.
3. The arrangement of the loose boss or the like J and leather bands I and the
method of crossing and attaching the latter to the rocking arms or levers O or the
like for the purpose of obtaining a perpendicular and parallel lift, substantially as
described and illustrated.
Dated this 23rd day of June 1992.
GEO.
DOWNING,
8, Quality Court, London, W.C., Agent.