Improvements in the Let-off Apparatus of a Loom for Weaving Cloth.
Year: 1894

page_text: Date of Application, 7th Apr., 1894
Complete Specification Left. 18th May, 1894-Accepted, 23rd June, 1894
PROVISIONAL SPECIFICATION.
Improvements in the Let-off Apparatus of a Loom for Weaving
Cloth.
I DAVID HENRY SINTON of Markethill in the County of Armagh in Ireland
Linen Manufacturer do hereby declare the nature of this invention to be as
follows:-
My invention relates to the let off motion of a loom for the weaving of linen
and consists in substituting for the ratchet wheel now and hitherto commonly
employed in the let off motion of the loom a large ratchet wheel having a wide
face and actuated by a number of pawls of various lengths so as to engage with the
ratchet at every shot of the weft or nearly so.
1
1004
HUGH
HYNDMAN,
6, Chichester Street, Belfast, Agent for Applicant.
COMPLETE SPECIFICATION.
Improvements in the Let-off Apparatus of a Loom for Weaving
Cloth.
I DAVID HENRY SINTON of Markethill in the County of Armagh in Ireland
Linen Manufacturer 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 :—
My invention relates to the let off motion of a loom for the weaving of linen and
consists in substituting for the ratchet wheel now and hitherto commonly employed
in the let off motion of the loom a large ratchet wheel having a wide or broad face
placed on the same shaft and actuated by a number of pawls of various lengths 80
as to engage with the ratchet wheel at every shot of the weft or nearly so.
The size of the substituted ratchet wheel is regulated by the space which the
loom will allow for its reception and the larger it can be made both in diameter
and width the more advantageous it will prove. I construct the teeth of this
wheel with a thick or blunt edge for the purpose of increasing their strength and
avoiding the fracture to which they have hitherto been very subject and I place
them in close succession on the periphery.
The number of pawls may also be increased with advantage.
The motion of the loom is transmitted to the pawls in the ordinary way by
a connecting rod through the slot in one end of which the stud carrying the
pawls instead of an independent stud passes and attached as usual at the other
end to a stud in the bracket bolted to the rocking rail of the loom.
connecting rod is preferably lengthened to suit the larger wheel and so that the
pawls may engage with the teeth at a higher position on the circumference.
The
I employ a bar of wire to prevent the pawls falling away or over and ceasing to
engage with the ratchet wheel.
I also enlarge the friction wheel which is employed for regulating the tension
of the yarn and the larger it can be conveniently made the greater will be its
efficiency.
By these arrangements the shots of the weft occur at regular intervals and a
more uniform and better grained web of cloth is produced.

page_text: And in order that my said invention may be more fully understood I shall now
proceed to describe the drawings on the sheet hereunto annexed the same letters of
reference indicating the same or corresponding parts of my said apparatus
throughout all the figures.
Fig. I is an elevation of the ordinary rocking bracket shaft and worm shewing
an enlarged ratchet wheel and three pawls, a lengthened connecting rod, a rod of
wire to prevent the pawls falling over or away and an enlarged friction wheel.
Fig. II is a plan of the same parts as are shewn in Fig. I and
Fig. II is an end view of the same parts as are shewn in Fig. I, except the
worm on the shaft.
a is the large ratchet wheel placed upon the ordinary shaft of the loom and
having thick or blunt teeth closely occurring on its periphery; b b b are pawls
by which the ratchet wheel a is actuated; c is the lengthened connecting rod
with the slot at the upper end to receive the stud d which carries the pawls
and attached at the lower end by a stud in the bracket bolted to the rocking rail
of the loom as heretofore; e is the rod of wire to prevent the pawls falling
away or over from the ratchet wheel. a is the ordinary shaft of the loom carrying
the worm; y the ordinary bracket; and z the enlarged friction wheel.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I would have it to be.
understood that I do not claim as of my invention nor the exclusive use of ratchet
wheels and pawls friction wheels and connecting rods except when the same are
constructed and employed according to my invention nor do I claim the use of
shafts worms rocking brackets and rails or studs or any of the separate mechanical
parts of the apparatus employed by me but I claim,
1. The production of the shots of weft in a web at regular intervals by means
of a ratchet wheel and pawls constructed and employed substantially as hereinbefore
described and shewn in the drawings hereunto annexed.
2. The uniformity of tension of the warp in weaving linen by means of a ratchet
wheel and pawls constructed and employed substantially as herein before described
and shewn in the drawings hereunto annexed.
3. The manufacture and use in looms for weaving linen of a ratchet wheel and
two or more pawls constructed and employed substantially in the manner and for
the purposes herein before described and shewn in the drawings hereunto annexed
and
4. The combination and arrangement of parts constituting my improved let off
apparatus constructed fitted and employed substantially in the manner and for the
purposes hereinbefore described and illustrated by the drawings hereunto
annexed.
Dated this 17th day of May 1801
HUGH
HYNDMAN,
6, Chichester Street, Belfast, Agent for Applicant.