A Selfacting Stop and Brake for Sewing Machines.
Year: 1890

page_text: Date of Application, 1st July, 1890
Complete Specification Left, 1st Apr., 1891-Accepted, 2nd May, 1891
PROVISIONAL SPECIFICATION.
A Selfacting Stop and Brake for Sewing Machines.
THOMAS MARSDEN COCUROFT 12 Commercial Street Leeds Depôt Manager
and ROGER FARMER 16 School Croft Sheffield Mechanic do hereby declare the
nature of this invention to be as follows:-
<<
This invention relates to sewing machines, and is generally applicable to sewing
machines of either a single or multiple needle type, in which a
take up
"lever is
employed; and has for its object an arrangement of mechanism to be set in motion.
by the breaking of a needle thread, for selfactingly disconnecting the friction gear
and braking a machine when driven by power; or for braking only when operated
by treadle.
In carrying out our invention we secure to the upper part of the "take up" lever,
a flat spring with an eye concentric with the "take up "lever eye.
The needle thread after passing between the usual tension discs is led first
through the "take up" lever eye, then through the eye of the said spring to
the needle.
"
Pivotted to the machine head and projecting across the "take up lever is a
detent lever; this lever takes into a detent wheel fixed on a shaft extending length-
wise of the machine, said shaft carries at its rear end a spur pinion, geared to a
train of wheels, said train gearing with a sector integral with the brake.
The brake is freely mounted upon a stud and has a shoe for bearing against
the balance wheel and also carries a projecting arm with an incline formed
thereon, said incline pressing the friction pulley or lever from contact with the
balance wheel.
Said brake, sector, train of wheels, shaft and detent wheel are set in motion by
the pressure of a helical spring taking under the brake heel.
The action of the herein before described mechanism is as follows,-When a needle
thread breaks, the flat spring is released and rebounds against and lifts the detent
lever free from the detent wheel, the pressure of the helical spring sets the train of
wheels in motion and brings the brake forward to bear against the balance wheel,
or the projecting arm simultaneously disconnects the friction gear by the incline
formed thereon being pressed against the friction pulley or lever.
Dated this the Thirtieth day of June 1890.
THOMAS MARSDEN COCUROFT.
ROGER FARMER.
COMPLETE SPECIFICATION.
A Selfacting Stop and Brake for Sewing Machines.
THOMAS MARSDEN COCUROFT Depôt Manager of 12 Commercial Street-
Leeds and ROGER FARMER Mechanic of 16 School Croft Sheffield both in the
County of York 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 to sewing machines, and is generally applicable to machines,
of either single or multiple needle type, in which a take up lever is employed; and
has for its object an arrangement of mechanism to be set in motion by the breaking
of a needle thread, for selfactingly disconnecting the friction gear and braking a
machine when driven by power, or for braking only when driven by treadle.
i Dan Q17

page_text: nereto annexed, in which corresponding letters indicate corresponding parts
the figures.
Fig. I. a back elevation,
Fig. II. a plan
Fig. III. an end elevation of brake and friction gear.
Fig. IV. reverse end elevation of detent lever, detent wheel, and take up lever.
Fig. V. section of friction gear.
Fig. VI. end elevation with friction gear removed.
Fig. VII. a view in detail showing spring closed upon the take up lever.
Figs. VIII, IX., and X. detached views of take up lever and spring 6, (half size).
Fig. XI. a detail view of brake heel &c.
We secure to the usual take up lever A, a flat spring b with an eye concentric
with the eye of said lever A.; said spring 6 is divided into two parts by a slit
when two needle threads are simultaneously used.
A detent lever d, is pivotted at e and projects across the take up lever A ; said
lever d takes into a detent wheel f, fixed on a shaft
extends length-
said shaft
9,
wise of the machine; shaft g carries at its rear end, a spur pinion h, geared to a
train of wheels i, said train of wheels gearing into a sector j secured to the brake k.
Said brake k carries a projecting arm with an incline formed at m, said incline m
pressing back the well known friction lever from contact with the friction stud and
pulley upon the hereinbefore described mechanism being set in motion by the
breaking of a needle thread.
Said brake is freely mounted upon a stud n and has a shoe o for bearing against
and braking the balance wheel p.
The brake k, sector j, train of wheels i, shaft g, detent wheel and projecting
arm l, derive their motion from the pressure of helical spring 9 (Fig. XI.) taking
under the heel of the brake k, or as a preferable modification we employ a
projections, carried forward from the brake k as shown in Figs. I., III. and VI.
with a flat spring t subjecting the projections to spring pressure in a downward
direction. We have not described the friction driving gear, nor the mode of
applying foot pressure to same in detail; further than to exhibit a section of friction
pulley in Fig. V., because they are too well known to need further description; but
we have shown a constant pressure exerted by a spring in connecting the friction
lever and pin in Fig. I and III. as an alternative, when foot
dispensed with.
pressure
is
The action of the hereinbefore described mechanism is as follows.
The handle part w of brake k is pushed back carrying the sector j against stop a,
upon which the detent lever d falls by its own weight into the catch y on detent
wheelf, and thereby holds the brake k free from contact with the balance wheel p
and the arm also free from contact with the friction lever.
The needle thread after passing between the tension is led first up through the
take up lever eye, then through the eye of spring b to the needle.
The machine now being operative and stitching, said spring 6 is drawn down
close to the take up lever A (as shown in Fig. IX.) at the moment of tightening
each successive stitch, by the upward movement of the take up lever A, and the
resistance on the thread in passing through the usual tension device.
When a needle thread breaks, it releases spring (Fig. VIII.) said spring b
rebounds against and lifts detent lever d free from detent wheelf; this breaking of
the needle thread usually takes place, when the take up lever is drawing the last
formed stitch tight, but the spring 6 is equally effective when the thread breaks in
any other position, by the take up lever A carrying the open spring 6 against the
detent leverd and releasing or lifting same. Upon the detent lever d being released
as hereinbefore described, the spring pressure applied by spring t sets the train of
wheels i in motion and thereby brings the brake forward to bear against the
balance wheel p, and also brings the arm with incline m' forward to simultaneously
disconnect the friction lever.

page_text: In Figs. I., II., IV. and X. we show the application of our invention to a
machine sewing with two needles simultaneously, in which spring b is duplicated by
division into two parts, either part of said spring b acts independently of the other
in lifting or releasing detent lever d-that is to say-if either of two needle threads
break, the hereinbefore described mechanism is set in motion by either breakage
independently of the other.
For the purpose of stopping the machine at the will of the operator, we attach to
detent lever d, a handle : upon drawing back said handle z free from detent
wheelf, the hereinbefore described mechanism brakes the balance wheel and dis-
connects the friction lever.
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 A selfacting brake and disconnector of friction gear for sewing machines,
actuated by spring pressure and selfactingly set in motion by the breaking of either
of two needle threads: substantially as and operated in the manner and for the
purpose herein described and illustrated in the accompanying drawings.
Secondly A brake for sewing machines actuated by spring pressure and self-
actingly set in motion by the breaking of either of two needle threads as herein
specified and illustrated in the accompanying drawings.
Thirdly-The use in a sewing machine of a single or duplicated spring 6 for
lifting or releasing a detent lever d from catch y on detent wheel f, substantially as
herein specified and illustrated in the drawings hereto annexed.
Fourthly The combination in a brake and disconnector for acting simultaneously
upon the balance wheel and friction gear of a sewing machine-of the following
instrumentalities, a single or duplicated spring b, attached to a take up lever A ;
a detent lever d pivotted at e; a detent wheelf having a catchy; a shaft g carrying
said detent wheel, and at its rear end a spur pinion h, a train of wheels i geared to
said spur pinion; a sector j geared with said train; a brake k mounted upon stud n
carrying said sector and also arm with incline m; a heel subject to spring
pressure from spring 9 (Fig. XI.) or the modification of spring pressure from flat
spring & impinging upon projections attached to brake k: substantially as herein
specified and illustrated in the drawings hereto annexed.
Dated this the Thirty-first day of March 1891.
THOMAS MARSDEN COCUROFT.
ROGER FARMER.