Improvements in Trimming Attachments for Sewing Machines.
Year: 1899

page_text: Date of Application, 16th Jan., 1899
in Onanifontion Loft
12th Oct
1000 Accented
40th Nov
1000
PROVISIONAL SPECIFICATION.
Improvements in Trimming Attachments for Sewing Machines.
We, THE SINGER MANUFACTURING COMPANY, of Kilbowie, Dumbartonshire,
Sewing Machine Manufacturers, and WILLIAM MORT, Engineer, in the employ-
ment of said Firm, do hereby declare the nature of this invention to be as
follows:-
This invention has for its object to provide a sewing machine trimmer of
improved construction operated from above the work-plate and wherein the
knives or cutters are formed by straight blades which are so fitted and carried
clear of obstructions that they may be made of unusual length so as to provide for
wear due to frequent sharpening without necessitating renewal of the blades.
The improved trimmer is applicable to all classes of sewing machines in which
the goods have to be cut or trimmed during the sewing operation, but in one
form of the invention it is particularly adapted for use in scalloping or trimming
curtains while being taped, bound or hemmed.
The improved trimmer is composed of a vertically reciprocating knife blade
whose cutting edge at the lower end acts in conjunction with the end of a
stationary horizontal cutter blade to shear or trim the edge of the fabric as it is
traversed over the throat plate of the machine during the sewing operation.
The horizontal cutter is laid transversely of the line of feed over the bed plate
to which it is secured by a clamp extending across it and secured at its rear end
to the bed plate by a screw or screws which may be readily loosened for adjusting
the cutter blade, whilst its forward end in proximity to the cutting edge is guided
in a shallow groove or recess cut for it in the throat plate so that during adjust-
ment lengthwise to bring it into shearing contact with the reciprocating cutter
it is maintained in position against lateral displacement, and the use of guide
slots in the blade which limit its effective length is avoided.
The vertical reciprocating cutter blade is formed with a sharpened and beveled
cutting edge which is fitted to bear against the end of the lower cutter, and may
have the usual depending tail piece working against a guide block below the throat
plate to maintain it in close contact with the stationary cutter. This tail piece
may however be dispensed with, the cutter blade being adjustably but rigidly
secured in close proximity to its lower end by means of a clamp to a guide bracket
attached to a vertical reciprocating cutter bar operated in any usual manner from
the needle bar or from a cam on the shaft which gives motion to the needle bar.
This guide bracket may terminate under the end of the overhanging arm of the
machine in which case it may be necessary to shorten the cutter blade: but when
the machine is of the class adapted for taping or binding curtains and a hemming
or binding attachment is interposed between the cutter blade and the sewing
needle, the guide bracket is extended out clear of the head or end of the over-
hanging arm of the machine so that the vertically reciprocating cutter blade is
held in a guide way in the bracket clear of the machine arm and may be carried

page_text: upwards to any desired extent alongside said head without interfering with the
operating parts of the machine.
Dated this 14th day of January 1899.
WALLACE FAIRWEATHER,
Of the Firm of Cruikshank & Fairweather,
Chartered Patent Agents,
Saint Vincent Street, Glasgow, Agent for the Applicants
improvements in Trimming Attachments for Sewing machines.
We, THE SINGER MANUFACTURING COMPANY, of Kilbowie, Dumbartonshire,
Sewing Machine Manufacturers, and WILLIAM MORT, Engineer, in the employ-
ment of said Firm, 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 has for its object to provide a sewing machine trimmer of
improved construction operated from above the work-plate and wherein the
knives or cutters are formed by straight blades which are so fitted and carried
clear of obstructions that they may be made of unusual length so as to provide for
wear due to frequent sharpening without necessitating renewal of the blades.
The improved trimmer is applicable to all classes of sewing machines in which
the goods have to be cut or trimmed during the sewing operation, but in one
form of the invention it is particularly adapted for use in scalloping or trimming
curtains while being taped, bound or hemmed.
The invention is illustrated by the accompanying drawings, Fig. 1 being a
vertical section through the head of a sewing machine, transversely of the bed,
Fig. 2 is an elevation at right angles to Fig. 1, and Fig. 3 is a plan of Fig. 1.
The improved trimmer is composed of a vertically reciprocating knife blade A
whose cutting edge at the lower end acts in conjunction with the end of a
stationary horizontal cutter blade B to shear or trim the edge of the fabric as it
is traversed over the throat plate (of the machine during the sewing operation.
The horizontal cutter B is laid transversely of the line of feed over the bed
plate 1) to which it is secured by a clamp E extending across it and secured at its
rear end to the bed plate I) by a screw E or screws which may be readily
loosened for adjusting the cutter blade B, whilst its forward end in proximity to
the cutting edge is guided in a shallow groove or recess ( cut for it in the throat
plate C so that during adjustment lengthwise to bring it into shearing contact
with the reciprocating cutter A it is maintained in position against lateral dis-
placement, and the use of guide slots in the blade B which limit its effective
length is avoided.
The vertical reciprocating cutter blade A is formed with a sharpened and
beveled cutting edge A which is fitted to bear against the end of the lower
cutter B, and may have the usual depending tail piece working against a guide
block below the throat plate to maintain it in close contact with the stationary
cutter. This tail piece or the guide therefor may however he dispensed with, the
cutter blade A being adjustably but rigidly secured in close proximity to its
lower end by means of a clamp F to a carrying bracket G, the cutter A being
first placed in a groove G¹ in said bracket to prevent side displacement. The
bracket is attached to a vertical reciprocating cutter bar H operated in any
usual manner from the needle bar X or from a cam on the shaft which gives
motion to the needle bar, or in any other suitable manner. This guide bracket G

page_text: may terminate under the end of the overhanging arm of the machine in which
case it may be necessary to shorten the cutter blade A, or to provide a clearance
hole in the underside of the head of the machine, where this is possible; but when
the machine is of the class adapted for taping or binding curtains and a hemming
or binding attachment, such as I, is interposed between the cutter blade A and the
sewing needle J, the guide bracket G is extended out clear of the head or end of
the overhanging arm of the machine, as shewn, so that the vertically reciprocating
cutter blade is held in the guide slot G in the bracket clear of the machine arm
and may be carried upwards to any desired extent alongside said head K without
interfering with the operating parts of the machine. A guard L is provided
which surrounds the lower end of the reciprocating cutter A, in order to protect
the fingers of the operator.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what
we claim is:
-
1. A trimming attachment for sewing machines, the several parts of which are
constructed, arranged, and combined, substantially as set forth.
2. A trimming attachment for sewing machines, consisting of the combination
of a vertically reciprocating cutter and a horizontal stationary cutter against
which the vertically reciprocating cutter shears or trims the edge of the fabric,
said cutters being carried above the work plate and formed of straight blades to
provide for wear due to frequent sharpening, substantially as described.
3. In a sewing machine the combination with a stationary cutter carried above
the throat plate of a vertical cutting blade carried in a groove in a reciprocating
bracket, and a clamp for securing the blade in said slot and permitting of vertical
adjustment, substantially as described.
4. In a trimming attachment for sewing machines, the combination with a
vertically reciprocating cutter, of a stationary cutting blade secured above the
work-plate, a groove in the throat plate in which the forward end of the blade is
guided, and a clamp extending across said stationary cutter and adjustably secured
to the bed plate of the machine, substantially as described.
Dated this 12th day of October 1899
WALLACE FAIRWEATHER,
Of the Firm of Cruikshank & Fairweather,
Chartered Patent Agents,
62, Saint Vincent Street, Glasgow, Agent for the Applicants.