Improvements in the Construction of Knives used for Cutting the Pile of Velvets and other Pile Fabrics.
Year: 1891

page_text: Date of Application, 4th Aug., 1891
Complete Specification Left, 4th May, 1892-Accepted, 30th July, 1892
PROVISIONAL SPECIFICATION.
Improvements in the Construction of Knives used for Cutting the
Pile of Velvets and other Pile Fabrics.
I JAMES HOYLE SMITH of 8 Abbey Grove Eccles in the County of
Lancaster Fustian Cutter do hereby declare the nature of this invention to
be as follows:
This invention relates principally to the construction of knives for cutting the
pile of velvets and other pile fabrics such as are described in the Specification of
Letters Patent No. 16996 granted to myself Andrew Goddard, Lloyd Higginbottom
and Thomas Mannock and dated the 10th day of December 1887, but the said
invention is also applicable to other fustian or pile cutting knives of similar con-
struction.
In fustian cutting knives of this description the arm which carries the knife
holder is held in position by a trigger so arranged that when the point of the knife
penetrates the cloth the latter coming against the trigger causes the same to release
the knife holder and allow a spring to withdraw the arm and knife holder back-
wards so as to prevent further injury to the cloth and this mechanism has hitherto
been so arranged that the spring which held the knife forward also acted upon the
trigger in such a way that when the knife penetrated the back of the fabric the
action of the latter having a tendency to force back the knife caused the spring to
press with increased force upon the trigger and thus made it more difficult to
"let off," so that occasionally a long cut was made in the fabric before the
trigger could release the knife holder and allow it to withdraw the knife.
The object of the first part of my invention is to remedy this defect which I
propose to do by so arranging the said spring or springs that the pull of the cloth
against the knife holder in the event of the knife passing through the fabric,
instead of increasing the forward pressure against the trigger shall so act as to
relieve such pressure and assist the trigger in releasing the catch which holds the
knife holder in position.
The object of the second part of my present invention is to impart to the arm
which carries the knife holder a compound motion so that it not only moves in the
arc of a circle around its own pivots, when the knife is to be withdrawn, but also
that the pivots themselves have imparted to them an upward or backward
motion whereby the withdrawal of the knife becomes much more effectual and
instantaneous.
This may be effected in two ways that is to say, the pivots of the arm may be
mounted in the free end of a lever which is pivotted to the frame and acted upon
by a spring being held down by a catch and released by the trigger, or the pivots
of the arm, and the trigger are carried in a slide which is held by a catch and
when released by the action of the trigger this slide is rapidly drawn back by a
spring, and it will be evident that in either case in the event of the point of the
knife penetrating the back of the cloth the trigger and arm will both travel back
rapidly with the cloth at the same time that the trigger is releasing the arm and
allowing it to turn over backwards upon its pivots; and thus only a simple puncture
will be made in the cloth before the knife is withdrawn.
Dated this First day of August 1891
GEO. DAVIES & SON,
4, St. Ann's Square, Manchester, Agents for Applicant.

page_text: '
COMPLETE SPECIFICATION.
Improvements in the Construction of Knives used for Cutting the
Pile of Velvets and other Pile Fabrics. .
I JAMES HOYLE SMITH of 8 Abbey Grove Eccles in the County of Lancaster
Fustian Cutter, 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 :-
This invention relates principally to the construction of knives for cutting the
pile of velvets and other pile fabric such as are described in the Specification of
Letters Patent No. 16996 granted to myself, Andrew Goddard, Lloyd Higginbottom
and Thomas Mannock and dated the 10th day of December 1887, but the, said
invention is also applicable to other fustian or pile cutting knives of similar, con-
.struction.
In fustian cutting knives of this description the arm which carries the knife
holder is held in position by a trigger so arranged that when the point of the knife
penetrates the cloth the latter coming against the trigger causes the same to release
the knife holder and allow a spring to withdraw the arm and knife holder back-
wards so as to prevent further injury to the cloth; and this mechanism has hitherto
been so arranged that the spring which held the knife forward also acted upon the
trigger in such a way that when the knife penetrated the back of the fabric the
action of the latter having a tendency to force back the knife caused the spring to
press with increased force upon the trigger and thus made it more difficult to
"let off," so that occasionally a long cut was made in the fabric before the trigger
could release the knife holder, and allow it to withdraw the knife.
The object of the first part of my invention is to remedy this defect, which I
propose to do by so arranging the said spring or springs that the pull of the cloth.
against the knife holder, in the event of the knife passing through the fabric, instead
of increasing the forward pressure against the trigger, shall so act as to relieve
such pressure, and assist the trigger in releasing the catch which holds the knife
holder in position.
This will be clearly illustrated on reference to Fig. 1 of the accompanying
drawings, which is an elevation in section of so much of a knife for cutting fustians
as is necessary to illustrate my invention.
a is the pivot on which the arm or knife holder 6 works, b' is the spring attached
to a cord passing around the pulley to withdraw the knife c at a "fault."
The arm bis held in place by a spring bolt 3 and thus as soon as the knife passes
through the cloth x the pull of the latter which is in the direction of the arrow
assists the spring b¹ to overcome the bolt 63 and release and withdraw the arm or
knife holder b.
The object of the second part of my present invention is to impart to the arm
which carries the knife holder a compound motion so that it not only moves in the
arc of a circle around its own pivots, when the knife is to be withdrawn, but also
that the pivots themselves have imparted to them an upward or backward motion
whereby the withdrawal of the knife becomes more effectual and instantaneous..
This may be effected in two ways as will be readily seen on reference to Figs. 2
and 3 of the annexed drawings.
In the modification shewn on Fig. 2 the pivot a of the arm b.which carries the
knife and guide d is mounted in the free end of a frame or lever e pivotted
at ex to the frame or handle. The said lever e is acted upon by a spring. and
pulley and held down by a catch lever 'held in place by the trigger i and
stopped by the pin fixed to the frame or handle f.
The arm b is held in place by the part h' of the same catch h and rotated on its
pivot a by the spring and pulley b².
Thus when the catch is released by the trigger i the spring. 9 actuates the frame

page_text: or levere and raises it on the pivot ex and the spring b' simultaneously actuates
the arm b, thereby increasing the rapidity of the withdrawal of the knife c when
the latter passes through the fabric.
In the modification shown at Fig. 3 the arm band pivot a are carried on a sliding
frame el a small cam or wheel 2 is fixed on the fulcrum or pivot of the catch lever h
which is also carried by the frame e' a spring latch lever engages with this cam
or wheel h as shown and retains the sliding frame in place as long as the catch his
held by the trigger i, hut if the knife goes through the fabric, as soon as the said
catch is released and the spring 6' withdraws the knife holder, the rocking of the
catch rotates the cam or wheel h² and releases it from the latch lever h³ and the
spring g* can draw back the sliding frame e' in the slot 1 of the frame or handle f
and increase the rapidity of the withdrawal of the knife c from the fabric and
thus only a small slit or puncture will be made therein.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. In an automatically released knife for cutting pile fabrics so arranging the spring
and catch which hold the knife in place, that the action of the cloth upon the knife
(in the event of the latter passing through the fabric) shall itself assist the spring
which withdraws the knife in releasing the knife holder from its catch substantially
as and for the purposes hereinbefore described.
2. In an automatically released knife for cutting pile fabrics the combination
with the knife holder and its adjuncts of a lever or a sliding frame, so mounted in
the main frame or handle that when the knife is to be withdrawn the knife holder
turns on its pivot or pivots and at the same time the latter is or are withdrawn with
the aforesaid lever or sliding frame, thereby rendering the withdrawal of the knife
from the cloth more rapid, substantially as and for the purposes hereinbefore set
forth.
Dand th] 1
1000
GEO. DAVIES & SON,
4, St. Ann's Square, Manchester, Agents for the Applicant..