IMPROVE- MENTS IN LOOMS FOR WEAVING
Year: 1875

page_text: LETTERS PATENT to Rufus Yates and George Brierley, both of
Preston, in the County of Lancaster, for the Invention of "IMPROVE-
MENTS IN LOOMS FOR WEAVING."
Sealed the 19th May 1876, and dated the 24th December 1875.
PROVISIONAL SPECIFICATION left by the said Rufus Yates and
George Brierley at the Office of the Commissioners of Patents, with
their Petition, on the 24th December 1875.
We, RUFUS YATES and GEORGE BRIERLEY, both of Preston, in the
County of Lancaster, do hereby declare the nature of the said Inven
tion for "IMPROVEMENTS IN LOOMS FOR WEAVING," to be as follows:-
This Invention relates to that class of looms for fancy weaving,
wherein the shed is caused to open by means of what is well known as
the “dobby” or "index machine," and consists in an improved method
of actuating the knives for raising the hooks in such machines.
The class of "dobby" to which this Invention is chiefly applicable is
that in which the two knives work vertically, and the principal advantages
consist in the increased steadiness of working; and the saving of wear
:

page_text: and tear obtained by acting directly from the tappet shaft upon the
knives independently of each other. These knives are made longer than
usual and are pivoted at one extremity, just above the junction of the
warps and the woven cloth, so that each hook is raised to the proper
height to keep the shed even in proportion to its distance from the
fulcrum. The other extremities of these knives are connected by means
of rods to treadles, which rest by their own weight on tappets keyed on
the tappet shaft, and thus at each revolution the knives are alternately
thrust up by means of the connecting rods, and caused to lift the hooks
that are presented to them by the pattern.
*SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Rufus Yates and George Brierley in the Great
Seal Patent Office on the 23rd June 1876.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, Rufus
YATES and GEORGE BRIERLEY, both of Preston, in the County of Lan-
caster, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-fourth day of December, in
the year of our Lord One thousand eight hundred and seventy-five,
in the thirty-ninth year of Her reign, did, for Herself, Her heirs
and successors, give and grant unto us, the said Rufus Yates and
George Brierley, Her special license that we, the said Rufus Yates and
George Brierley, our executors, administrators, and assigns, or such
others, as we, the said Rufus Yates and George Brierley, our executors,
administrators, and assigns, should at any time agree with, and no
others, from time to time and at all times thereafter during the term
therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
LOOMS FOR WEAVING," upon the condition (amongst others) that we, the
said Rufus Yates and George Brierley, our executors or administra-
tors, by an instrument in writing under our, or their, or one of
their hands and seals, should particularly describe and ascertain the

page_text: nature of the said Invention, and in what manner the same was to be
performed, and cause the same to be filed in the Great Seal Patent
Office within six calendar months next and immediately after the date
of the said Letters Patent.
NOW KNOW YE, that I, the said George Brierley (on behalf of
myself and the said Rufus Yates) do hereby declare the nature of the
said Invention, and in what manner the same is to be performed, to
be particularly described and ascertained in and by the following state-
ment and accompanying Drawings :-
This Invention relates to that class of looms for fancy weaving
wherein the shed is caused to open by means of what is well known as
a "dobby" or "index machine " and consists in an improved method of
actuating the knives for raising the hooks in such machines.
"
The class of "dobby to which this Invention is chiefly applicable is
that in which the two knives work vertically, and the principal advantages
consist in the increased steadiness of working and the saving of wear
and tear obtained by acting directly from the tappet shaft upon the
knives independently of each other. These knives are made longer than
usual, and are pivotted at one extremity above the junction of the
warps and the woven cloth, so that each hook is raised to the proper
height to keep the shed even in proportion to its distance from the
fulcrum. The other extremities of these knives are connected by means
of rods to treadles, which rest by their own weight on tappets keyed on
the tappet shaft, and thus at each revolution the knives are alternately
thrust up by means of the connecting rods, and caused to lift the hooks
that are presented to them by the pattern.
The tappets are keyed upon the tappet shaft in opposite directions so
that one knife falls as the other rises.
Such being the nature and object of our said Invention, we will now
proceed to describe in detail the manner in which the same is to be or
may be performed or carried into practical effect, and in order that the
same may be clearly understood we have annexed hereunto a Sheet of
Drawings illustrative thereof, and have marked the same with figures
and letters of reference corresponding with those in the following
explanation thereof.
Fig. 1 in the annexed Drawing is a side elevation of so much of a
power loom as is necessary for the illustration of our Invention, a, a,

page_text: being the framing of the loom; b, b, the "dobby" or index machine;
and c, c, the tappet shaft. The knives d, d, of the "dobby" are made in
The
the form of levers, and are pivotted at a point e above the cloth.
outer ends of the knives d, d, are connected by thrust rods f, f, to two
rollers or bowls g, g, carried by levers h, h, and resting upon two tappets
or cams i, i, which are keyed in opposite positions on the tappet shaft
c, c. It will therefore be obvious that the two knives will be worked
alternately and entirely independent of each other, and hence their action
will be much more steady and certain, and as the knives are both
pivotted upon a centre above the cloth the shed will be regular and conical.
Fig. 2 is a detached view of a modification of this arrangement. The
thrust rods ff, of the knives d, d, instead of being connected as before
are attached to two short levers k, k, projecting (one on each side) from
a rocking shaft / to which a rocking motion is given by a short lever m
and a connecting rod n, attached to a crank pin o fixed in a face
plate i, i, which is keyed on the tappet shaft c in place of the two camś
or tappets employed in the first described arrangement.
It will be evident that many other slight variations may be made in
the mechanical details of the arrangement without departing from the
peculiar distinctive features of our Invention.
Having now described the nature and object of our said Invention,
together with the manner in which the same is to be or may be performed
or carried into practical effect, we wish it to be understood that we claim
as our Invention, making the knives of dobbies or index machines in
the form of levers pivotted above the cloth and actuating the same
directly from the tappet shaft, and independently from each other,
substantially as and for the purposes herein-before set forth and
described.
In witness whereof, I, the said George Brierley (on behalf of
myself and the said Rufus Yates), have hereunto set my hand
and seal, this Twentieth day of June, in the year of our Lord
One thousand eight hundred and seventy-six.
GEORGE BRIERLEY. (L.S.)