IMPROVEMENTS IN LOOMS FOR WEAVING
Year: 1882

page_text: PROVISIONAL SPECIFICATION left by Thomas Blackhurst at the Office
of the Commissioners of Patents on the 12th April 1882.
THOMAS BLACKHURST of Preston in the County of Lancastor, IMPROVEMENTS
IN LOOMS FOR WEAVING,
This invention of improvements in looms for weaving has reference to the dobby
or jacquard mechanism and consists in the employment of a novel arrangement of
apparatus more particularly applicable for producing the cross borders of pocket.
handkerchiefs, table cloths, or other such like articles. In existing arrangements
where the pattern of the cross border consists of a number of similar bars or
stripes, each bar or stripe requires its own system of cards or lattices and pegs,
whereas by my invention the same system of cards or lattices and pegs which
produces the first bar or stripe is made available for producing as many succeeding
bars or stripes as may be required to make up the cross border pattern. According
to my invention the card barrel or cylinder in conjunction with the knives and
hooks and the healds or staves is operated in the usual or any convenient manner.
To the outer framing of the dobby I fix a stud carrying a catch wheel rotated by
a finger receiving motion at each rotation of the tappet shaft. The boss of the
catch wheel is extended outwardly and forms a pulley, and a corresponding roller
is mounted on a movable stud some distance below. Around the pulley and the
roller is stretched an endless belt provided upon its outer surface with two or more
projecting ribs which determine-according to their relative distances from each
other-the distances apart of the cross borders and the periods during which the
card barrel or cylinder is to be rotated as hereinafter explained. A suitably
mounted sliding rack in a vertical or diagonal position having on its outer edge
teeth or indentations is so arranged near the side of the dobby as to be lifted or
raised by the action of a lever and catch actuated by the ordinary jacquard or
dobby mechanism. The hook which pulls over or rotates the card barrel is
connected to the upper end of the sliding rack by a cord or other convenient means
to the end that when the sliding rack is raised to the required height the card
barrel hook will be lifted out of action thereby causing the rotation of the card
barrel to cease until the sliding rack and with it the card barrel hook is lowered.
As the sliding rack is raised it is prevented from falling back by a stop catch
forming one end of a bell-crank lover whose other end forins a finger the
extremity of which is in a position adjacent to the outer surface of the endless belt

page_text: heroinabove referred to. The projecting ribs upon the endless belt in turn come
in contact with and lift up the finger thus causing the stop catch to be disengaged
from the sliding rack which being released drops to its normal position and allows
the card barrel hook to again rotate the card barrel whereupon the cross border will
be again produced until the card barrel hook is lifted out of action by the upward
movement of the sliding rack as herein before describod.
By the employment of an additional card barrel hook acting below the card
barrel the direction of rotation of the card barrel may be reversed by the lower
hook being lifted into action when the upper hook is lifted out of action thus
reversing the pattern to be produced. Such an arrangement is obviously applicable
to the weaving of table cloths in which the portion between the cross borders
consists of a pattern of which the second half is an inverse counterpart or
repetition of the first half.