Improvements in or connected with Loom Jacquards and Dobbies.
Year: 1891

page_text: COMPLETE SPECIFICATION.
Improvements in or connected with Loom Jacquards and Dobbies.
We, EDMUND BIRLEY of Fishwick Mills, Manufacturer, JOHN BRACEWELL
of 120 New Hall Lane, Mechanic, and WILLIAM CRAIG of 231 New Hall Lane,
Pattern Designer, all of Preston in the County of Lancaster, 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 to loom jacquards and dobbies as employed for lifting the
warps in looms and consists in improved arrangements of racks and wheels or sectors
for lifting the griffs or knives of said machines instead of the lever and links or
other mechanism hitherto employed by means of which improved arrangements a
steadier lift and straighter pull is obtained, our improvements being more especially
intended for double acting Jacquard machines and dobbies, but also applicable to
single acting machines.
On the sheet of drawings appended hereunto:
Figure 1 shows a side view and Figure 2 a front view of the parts or mechanism
arranged at the side of the loom for actuating the Jacquard machine.
Figure 3 a front view partly in section and Figure 4 a cross-section of the upper
part of a double acting Jacquard machine.
Figure 5 a side view and Figure 6 a front view of the upper part of a double-
acting dobby fitted with our improvements, only those parts that are necessary for
the ascertainment of our invention being shown on the drawings.
The tappet shaft a of the loom has a crank disc a' with crank pin or stud a² fixed
upon its outer end to which crank pin an adjustable connecting rod is attached in
the usual way. The upper end of the connecting rod is connected by a pin 63
to a vertical rack c, which slides and is guided in a groove of the bracket d. The
latter is fixed to a bracket which is bolted to a fixing d², The latter is fixed
upon a beam e supported from the joints of the shed or its equivalent. The
bracket is formed with a boss for a shaft extending to the Jacquard machine,
upon which shaft a spur wheel c¹ is fixed gearing with the rack c, so that the shaft/"
receives a rocking motion from the rack as the latter is moved up and down by the
crank pin a2 and rod b. A lever is fixed on the shaft and a spring fixed at
its other end to the beam e is attached to a pin at the end of the lever, the spring
and lever serving to balance the weight of the rack c and rod band to hold the
teeth of the wheel c' against the underside of the teeth of the rack c, thus preventing
backlash.
C
The shaft extends across the Jacquard machine and is supported in bearings g g
formed on brackets g g which are bolted to fixings g² g mounted upon and fixed
to the top of the Jacquard machine sides h. Upon the shaft fa spur wheel i is
fixed gearing with two racks (Fig. 4) which are guided in grooves of brackets kk
fixed to cross rails. The latter are bolted upon lateral extensions of the
brackets gg. The racks, which may be cranked at the lower ends as shown
by Figure 4, have the cross bearers m m fixed to them, from which the griff's n n
are suspended by rods o o in the usual way. As the shaft is rocked in alternate
directions by means of the crank a², rod b, rack c and wheel c¹, in the manner
hereinbefore described, the wheel i moves one of the racks i upwards and the other
downwards and thus lifts the griff's alternately, one of these balancing the other.
For wide Jacquard machines two or more spur wheels i with racks may be used.
In single acting Jacquard machines only one rack is used and the weight of the
griffs and harness balanced in any manner ordinarily used for this purpose, for
instance by means of a chain pulley fixed upon the shaft and chain with balance
weight or equivalent means. Instead of spur wheels sectors may be employed.
Price 877

page_text: The details of the brackets and other parts may be varied to suit the looms and
Jacquard machines to which the mechanism is applied.
Figures 5 and 6 show our improvement applied to a dobby. The shaft P
extends
to one side of the loom and may receive an oscillating motion by means of a crank,
rack and spur wheel similarly as hereinbefore described with reference to shaft,
but is preferably actuated by means of a tappet on the loom tappet shaft and a
treadle operated by the same which is connected by a rod to a lever on the shaft p
in the manner usually employed for operating dobbyshafts. On the shaft 2' two
sectors are fixed gearing with racks at which are guided in brackets s's
and supported on brackets fixed to the side frames eu of the dobby. To
the racks the griffs ww carrying the knives w² w³ are attached, by means of which
the wires u are lifted in the usual way. The two sets of racks, griffs and wires
balance each other like those of the Jacquard machine hereinbefore described.
The arrangement of details may be modified to suit different constructions of
dobbies.
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:
Firstly. The method of lifting the griffs of a jacquard or dobby by means of
racks and one or more spur wheels or sectors fixed upon a shaft to which a rocking
'motion is imparted, substantially as hereinbefore described and illustrated by the
drawings.
Secondly. In a Jacquard machine and loom the arrangement of a cross-shaft
supported in bearings attached to the said machine and a beam e or its equivalent
and fitted with one or more spur wheels or sectors each gearing with racks to which
the griffs of the said machine are attached and another spur wheel or sector on the
outside of the loom gearing with a rack receiving a reciprocating motion from a
crank on the tappet shaft, substantially as hereinbefore described and illustrated by
the drawings.
Thirdly. In a dobby the arrangement of sectors or spur wheels fixed on the
rocking shaft of the dobby and racks carrying the griffs and gearing with said
sectors or spur whels, substantially as hereinbefore described and illustrated by the
drawings.
Dated this 24th day of June 1891.
Per pro EMMOTT & CO., LIMITED,
Robert Wood, Secretary,
Agents for the Applicants.