IMPROVEMENTS IN SEWING MACHINES
Year: 1885

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CUTLEIE DI LUIFICATION.
I ALFRED JULIUS BOULT of 323 High Holborn in the county of Middlesex,
Engineer do hereby declare the nature of this invention for "IMPROVEMENTS
IN SEWING MACHINES (a communication from Rollin D. Tucker of Lynn,
Massachusetts, United States of America) 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 the nature thereof is fully
described herein after and specifically claimed.
Referring to the drawings Figure 1 is an isometrical projection of a sewing
machine embodying these improvements Figure 2 is a vertical longitudinal section
on dotted line x. x. Figure 3 is an end elevation of the machine while Figures 4, 5
and 6 are detail views of detached parts to be referred to again herein after.
The shaft A is provided with a pulley B to which power may be applied for
operating the machine connected to the shaft A is a crank arm C that operate to
vibrate the needle bar D. Said shaft A carries, on its end the customary looper E
that operates in connection with the needle F to form the usual chain stitch. The
construction and arrangement of these parts is common, and known to persons
skilled in the art.
In some classes of seaming it is customary to insert a welt strip between the
two pieces of material united together into a seam and to facilitate this operation
is one of the main objects of this invention.
Heretofore it has been customary to employ for this purpose, a fixed welt guide
but objection arises to the use of such a guide as it must necessarily be located back
from the needle hole to allow the feed clamps room. Space is thus left between
the end of the guide and the needle hole in which it is difficult to keep the welt
strip in place and this difficulty increases as the work is turned to seam round
curves or angles. To obviate this difficulty the welt guide is made moveable to the
end that it may be moved up to the needle hole to place the welt in position for
the descending needle and then back to allow the necessary room for the feed
clamps to operate. For this purpose the guide 6 is mounted upon the end of lever
arm 4, which arm being pivoted or journalled as shown to the machine frame
connects its rear end with a cam 5 (see Figure 2) on the shaft A. The cam 5 being
revolved, vibrates the arm 4, thus carrying the welt guide up to and away from
the needle hole.
I am aware that the guide may be attached directly to the feed clamp and
moved thereby and such an arrangement would for most purposes.be quite sufficient,

page_text: but in some cases it is desirable to have the welt pay out a little faster than the
material as when turning very sharp curves or angles and it is for this reason
more especially that it is preferable to operate the guide by mechanism independent
of the feed clamps.
The movement of the arm 4 may of course be made to conform to and be
simultaneous, with the movement of the feed clamps or it may be otherwise if
desired. The arm 4 it will be observed is adjustable on its journal pin 6 and the
amount of movement given to the guide may be modified by changing the adjust-
ment of the arm or by a suitable change of the cam 5. By these arrangements
the machine can be adjusted to all kinds of work and the guide may be caused
to move the same or more or less than the feed, or occasion requires, and either
simultaneously with the feed clamps or otherwise if desired. An ordinary braid
guide placed upon the arm 4 in place of the welt guide adapts the machine to the
work of binding and will. give better results than when the ordinary fixed
braid-guide or binder is employed.
Another essential feature of novelty in this invention is the curving or beveling
of the throat plate or bed plate backward from the needle hole towards the
operator, as shown, so that as the stitching proceeds, the welt advances through the
welt guide, and the stock is fed forward one piece above and one below the welt
guide, the lower piece raising, and the upper piece descending until they reach the
needle and receive the stitch at substantially the same angle to the horizon.. This
obviates the necessity of stitching into a single seam one piece of curved and one
piece of straight material as is the case when a straight or flat plate is used, such
operation results in à permanent bend or pucker of the seam and is entirely over
same by the curved plate. Another advantage of the curved plate is to afford
room, under the welt guide, for turning and moving and placing the material in
position.
Still another essential feature of novelty in this invention is the feed mechanism.
Said mechanism comprises two clamps both mounted on a moveable block and
arranged to clamp the opposite sides of the material and move the same along thus
preventing the welt strip from getting out of place during the feed movement.
To this end the upper clamp e is mounted upon an extension of the block Mas
shown in Fig 4. Said block also carries the spring lever b which lever is pivoted
to the block and bears one end against the block its opposite end being extended
forward as fully shewn in said Fig 4 which is a perspective view of these parts.
In the machine this forward end of spring b bears upward against the periphery
of cam S see Fig 3 which cam is fixed upon the shaft A and being revolved
thereby it operates to lift and depress the block and consequently the clamp e
Said spring b is arranged to yield freely at the point 8 thus allowing the clamp e
to lift and accommodate itself to pass over seams or various thicknesses or uneven
places in the material The block M is provided with a slot in its rear end to
receive the screw or pin N Said pin passing through the block fixed into the
machine frame thus holding the block M in position.
This arrangement allows the block to be advanced endwise on the pin as also to
be oscillated sufficiently to lift and depress the clamp e. The lower clamp dis
mounted on the small block H which is represented in perspective by Fig 6. of the
drawings Said block H is mounted upon the block M a hole f in the block H
being adapted to receive a pin h on the block M the two being thus combined
together as shown in Fig 3. Said block H is provided with a mouth m to receive
the cam R Said cam Ŕ (see Fig ) is fixed on the shaft A (see Fig 2) and when
revolved it operates to lift and depress the end of block H thus raising and
depressing the feed clamp d. The same cam operates to push backward the block H
which carries with it the block M by reason of the two being jointed together as
described thus.is effected the advance movement of the feed clamps.-The reverse
movements of the clamps is effected by a spring T which for this purpose is located
in a recess in block M with one end bearing against the pin N and its opposite end
against the block,

page_text: The thread tension is obtained through the clamps 10. 12. which are pivoted
together as shown in Fig 1. being held together or clamped by the spring 13
The clamps are opened by a rod 14 that has a crank connection with shaft A and
is so timed as to open the clamps at the moment when the needle is lifted.
The looper then takes off sufficient thread to formn the next stitch and thereupon
the clamps will close together thus securing the thread from further movement.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed as communicated to
me by my foreign correspondent I declare that what I claim is
1st In a sewing machine a welt guide arranged to perinit movement up to
and back from the needle hole and mechanism to give said movements to the welt
guide, substantially as described.
2. In a sewing machine, a welt guide; arranged to permit movement up to
and back from the needle hole and mechanism for giving said movements to the
guide, said mechanism being adapted to permit adjustment to vary the length of
movement of the welt guide relatively to the movement of the feed clamp,
substantially as described.
3. In a sewing machine, a welt or braid guide arranged to permit movement up
to and back from the needle hole and means to impart said movements to the
guide. Said means being arranged to move the welt guide simultaneously with
the movement of the feed clamps in whole or in part substantially as described.
4. A welt guide, through which the welt strip passes, while the stock passes
above and below it, in conbination with a sewing mechanism, and a throat or bed
plate beveled backward from the needle hole, substantially as described.
5. In a sewing machine a feed mechanism, composed of two clamps both carried
on a moveable block or carriage mechanism for advancing the block or carriage
and also for opening the clamps and means for moving the blocks and clamps in
reverse direction, substantially as described.
6. In a sewing machine a feed mechanism composed of two clamps both carried
on a laterally moveable block or carriage one of the clamps being moveable, cams
on the main shaft adapted to raise the moveable clamp and advance the block and
mechanism to depress the moveable clamp and return the block substantially as
described.
7. In a sewing machine a feed mechanism composed of an upper and lower clamp
for clamping the material, means for opening and closing and advancing and
returning the clamps and a moveable welt guide or braid guide arranged to guide a
welt or braid strip between the clamps substantially as described.
8. In a sewing machine an upper and lower clamp for clamping the material,
mechanism for advancing and returning the clamps also to open and close the
clamps, said means being arranged to close the clamps together with a yielding
pressure, substantially as described.
9. In a sewing machine the combination of the blocks M having clamp e a
cam on the main shaft A and the intermediate spring lever b all substantially as
described.
10th In a sewing machine the combination clamps 10. 12. the spring 13 and
rod 14 and operating shaft, all arranged to operate substantially as described.
ALFRED J. BOULT.