IMPROVEMENTS IN BUTTON-HOLE SEWING MACHINES
Year: 1881

page_text: .
"
LETTERS PATENT to Harry Mills, of Birmingham, in the County of Warwick,
for an Invention of "IMPROVEMENTS IN BUTTON-HOLE SEWING MACHINES."
A communication from abroad by Daniel Mills, of Philadelphia, Pennsylvania,
United States of America.
PROVISIONAL SPECIFICATION left by the said Harry Mills at the Office
of the Commissioners of Patents on the 19th March 1881.
"IMPROVEMENTS
HARRY MILLS, of Birmingham, in the County of Warwick.
IN BUTTON-HOLE SEWING MACHINES." [A communication from abroad by Daniel
Mills, of Philadelphia, Pennsylvania, United States of America.]
This Invention relates to machines for sewing or stitching button holes of that
kind or class which are finished and strengthened at each end by a bar formed of
a series of comparatively long stitches extending crosswise or transversely to the
direction of the length of the button-hole.
The said Invention is especially designed for application to machines provided
with a cloth clamp arranged in combination with a vertically reciprocating needle.
The said needle does not vary its position in working, but the leather or other
material in which the button holes are formed is moved by the said cloth clamp
to and fro in one direction across the path or line of the needle's motion to effect
the formation of the stitches, and has a feed motion in a direction transversely or
at a right angle to that of the said to and fro motion. The said cloth-clamp is
formed of two parts, namely, the lower part which serves as the cloth-plate or work
support, and the upper part which resembles in its arrangement the ordinary
presser foot of a sewing machine, and which when forced down upon the leather
or other material holds or clamps the same between its lower surface and the said
cloth plate, the said two parts of the clamp moving together during the operation
of sewing or stitching the button-holes. The said cloth plate or lower part of the
clamp forms part of a compound slide, that is to say, a slide which has motion
imparted to it longitudinally and transversely. One of these parts, which I term
the primary slide, has imparted to it the to and fro movement for forming the
D

page_text: stitches at the sides and the bars of the button-holes; and the other part, which I
term the secondary slide, imparts its feed-motion to the work..
The said primary slide receives its motion from a cam, which makes one
revolution to two strokes of the needle, and which is arranged in combination with
a detaining or controlling device, consisting of a cam and a yoke or saddle-piece;
the said yoke which surrounds the cam is attached to the primary slide. This cam
has on it a projection, and the yoke. has two projections and two recesses
diametrically opposite each other, and the projection on the cam acts alternately
on the said projections and recesses of the said yoke, and thereby varies the length
of the longitudinal movement of the cloth plate in such a manner as to effect the
stitching of first one side and then the other side, and to make short stitches at
the sides and longer stitches at the bars or ends of the button hole. The movement
of the secondary slide is derived from a right and left handed screw-cam mounted
on the same shaft as the cam of the detaining device. This screw cam is so
formed and arranged that through the medium of a lever it imparts to the cloth
clamp the required feed movement in both directions. One revolution of the
screw cam effects the forward and return feed movements, the button hole being
then completed.
•
The primary slide is not connected rigidly with the aforesaid yoke, but is
provided with a "let-off" device. This device consists of a two armed bar or piece
pivotted to the rod of the slide, and provided with springs in combination with
two stops or shoulders on the primary slide, the said arm and stops have inclined
surfaces which are kept in contact by the springs (with sufficient force to cause
the said slide to move with the rod when the said slide is quite free; but when by
reason of the action of the projections or shoulders on the said yoke and cam the
movement of the said slide is limited, the said springs allow the said bar to yield
so that the rod moves a short distance in each stroke without moving the slide.
The needle and shuttle operating devices and other parts of such machines are
too well known to need further description.
These button hole machines are very useful and are perfectly efficient within
the limits of their capacity, that is to say, each machine will work in a very
advantageous manner to make the stitches at the sides of the button hole of one
uniform length, and will also make the stitches at the sides or bars of one uniform
length, but this length in either case cannot be varied. Moreover, such machines
have no provision for regulating or varying the number of stitches in the bars
relatively to the stitches in the sides, that is to say, if the feed is adjusted for
fine and numerous stitches along the sides, it will make a proportionately great
number of stitches in the bars, and therefore in some cases it makes the latter
inconveniently hard or rigid; and on the other hand in some cases the bars have
an insufficient number of stitches and consequently are deficient with regard to
strength and durability.
But my Invention is designed to obviate these difficulties by providing such
machines with means for adjusting and controlling the operation of the cloth
clamp, to permit any desired variation in the length of the stitches and the relative
number thereof in the sides and bars.
I will first describe the means I employ for varying the length of the stitches.
In the said machines, as heretofore constructed, the cam which is enclosed by the
aforesaid yoke and which operates in combination therewith, as above described, has
its low portions (that is to say, the surface which extends between the two extremities
of its high portion or projection) of such a diameter as to allow only sufficient
movement to the yoke to move the primary slide the distance required to make
the stitches of the one determined length; but according to my present Invention
I make the difference between the said high and low portions of the said cam
much greater than heretofore, so that the diameter of the low portion is such as to
permit the yoke a greatly increased length of stroke, and I provide for controlling
the length of the stitches by using in combination with the aforesaid let-off device
of the primary slide a regulating screw, which is arranged to act upon stops on

page_text: the said slide, and which may be adjusted to allow the said slide free movement
to the full extent permitted by the aforesaid yoke and cam, and thereby cause the
machine to make long stitches; or it can be set to limit the stroke of the said slido
when it is desired to sew with short stitches. I prefer that the said screw should
have right and left hand threads, with nuts thereon arranged to act against the
said stops.
.
For regulating or altering the proportion of the number of stitches in the sides
with regard to those in the bars I provide means for adjusting the circumferential.
distance or length of the aforesaid projection or shoulder on the cam of the
detaining device. For this purpose I form the said projection or shoulder in two
parts, attached. to .clips or jaws which surround the other portion of the said cam.
At their lower extremity the said jaws have between them a spring, which tends
always to force and keep together the two parts of the projection; but between
these two parts I insert a block or piece, which is made taper to fit and slide
between the inner surfaces of the said parts of the projection. This sliding taper
or wedge shaped piece or block is connected with a screw whose head is arranged
in a convenient position to permit its manipulation; and by turning this head the
said block will be moved endwise or in line with the axis of the said cam, and
will thereby increase or diminish the length of the said projection or shoulder and
the proportion of the same to the length of the low or small portion of the said
cam. And as it is, while the projections of the yoke work upon the projection of
the cam that the side stitches are formed, it will be seen that by providing for
varying the extent of the said projection I can vary the number of stitches in the
sides in relation to the number of those in the bars of the button hole.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Harry Mills in the Great Seal Patent Office on the 19th September
1881.
HARRY MILLS, of Birmingham, in the County of Warwick. "IMPROVEMENTS
IN BUTTON-HOLE SEWING MACHINES." A communication from abroad by Daniel
Mills, of Philadelphia, Pennsylvania, United States of America.
This Invention relates to machines for sewing or stitching button-holes of that
kind or class which are finished and strengthened at each end by a bar formed of a
series of comparatively long stitches extending crosswise or transversely to the
direction of the length of the button hole.
The said Invention is especially designed for application to that class of machines
in which a cloth-clamp is arranged in combination with a vertically reciprocating
needle that does not vary its position in working relatively to the shuttle, and in
which the leather or other material wherein the button holes are formed is moved
by the said cloth-clamp to-and-fro in one direction across the path or line of the
needle's motion to effect the formation of the stitches, and has a feed motion in a
direction transverse or at right angles to that of the said to-and-fro motion, so that
one side of the button hole, then one bar, then the other side, and finally the other
bar, are successively stitched. The said cloth-clamp is formed of two parts, namely,
the lower part, which serves as the cloth-plate or work support, and the upper part,
which resembles in its arrangement the ordinary presser-foot of a sewing-machine,
and which when forced down upon the leather or other material holds or clamps:
the same between its lower surface and the said cloth-plate, the said two parts of
the clamp moving together during the operation of sewing or stitching the button-
holes. The said cloth plate forms one part of a compound slide, that is to say, a
slide which has motion imparted to it longitudinally and transversely.
One of these parts, which I term the primary slide, has imparted to it the
requisite to and fro movements for forming the desired length of stitches at the
sides and the bars at the ends of the button-hole; the other part of the slide, which
I term the secondary slide, imparts the feed motion to the work.
· The said primary slide receives its motion from a cam which makes one revolu-
tion to two strokes of the needle, and which is arranged in combination with a
detaining or controlling device consisting of a cam and a yoke or saddle piece.
The said yoke which surrounds the cam is indirectly connected to the primary
slide, as hereinafter described. This yoke cam has on it a projection, and the yoke
has two projections and two recesses diametrically opposite each other, and the
projection on the cam acts alternately on the said projections and recesses of the
said yoke, and thereby varies the length of the longitudinal movement of the cloth
plate in such a manner as to effect the stitching of first one side and then the other
side, and to make short stitches at the sides and longer stitches at the bars or ends
of the button hole. The movement of the secondary slide is derived from a right
and left handed spiral cam mounted on the same shaft as the cam of the detaining
device. This spiral cam is so formed and arranged that through the medium of a
lever it imparts to the cloth clamp the required feed-movement in both directions
to stitch both sides of the button hole. One revolution of this spiral cam effects
the forward and return feed movements, the button hole being then completed.
The primary slide is not connected rigidly with the aforesaid yoke, but is provided
with a "let-off" device. This device consists of a two-armed bar or piece pivotted
to the rod of the slide, and provided with springs in combination with two stops or
shoulders on the primary slide. The said arms and stops have inclined surfaces,
which are kept in contact by the springs with sufficient force to cause the said slide
to move with the rod when the machine is making the longest stitches; but when
the said machine is making the short stitches the said springs allow the said bar
to yield, so that the said rod moves a short distance in each stroke without moving
the alida

page_text: The needle and shuttle operating devices and other parts of such machines aré
too well known to need further description.
These button-hole machines are very useful, and are perfectly efficient within the
limits of their capacity, that is to say, each machine will work in a very advan-
tageous manner to make the stitches at the sides of the button-holo of one uniform
length, and will also make the stitches at the ends or bars of one uniform length,
but this length in either case cannot be varied. Moreover, such machines have no
provision for regulating or varying the number of stitches in the bars relatively to
the stitches in the sides, that is to say, if the feed is adjusted for making fine and
numerous stitches along the sides, the machine will make a proportionately great
Dumber of stitches in the bars, and therefore in some cases the latter are incon-
veniently hard or rigid; and on the other hand in some cases the bars have an
insufficient number of stitches, and consequently are deficient with regard to strength
and durability.
But my Invention is designed to obviate these difficulties by providing such
machines with means for adjusting and controlling the operation of the cloth clamp
to permit any desired variation in the length of the stitches and in the relative
number thereof in the sides and bars.
The said Invention is illustrated in the accompanying Drawing, in which,―
Figure 1 is a longitudinal section of part of a sewing-machine provided with my
improvements.
Figure 2 is an underside view of the parts connected with the cloth clamp of the
said machine.
Figure 3 is a side view of the aforesaid detaining device mounted upon the cam
for actuating the secondary slide; and
Figure 4 is a transverse section of the same on the line x, x, Figure 3.
Figure 5 is a side view; and
Figure 6 is a transverse section of one part of the said detaining device.
a is a portion of the frame of a sewing machine; 6 is the primary slide; c is the
secondary slide; d is the cam for operating the said slides longitudinally; e, f,
represent the cam and yoke constituting the detaining device; g is the screw cam
for operating the secondary alide through a suitable lever; h is the let-off device.
The remaining parts are hereinafter described.
I will first describe the means I employ for varying the length of the stitches.
In the said machines as heretofore constructed the cam e, which is enclosed by the
aforesaid yoke f, and which operates in combination therewith, as above described,
has its low portion e² (that is to say, the surface which extends between the two
extremities of its high portion or projection e¹) of such a diameter as to allow the
yoke only sufficient movement to move the primary slide 6 the distance required to
make the stitches of one determined length; but according to my present Invention
I make the difference between the said high and low portions of the said cam much
greater than heretofore, so that the diameter of the low portion e³ is such as to
permit the yokef a greatly increased length of stroke.
This increased length of stroke would be excessive for many kinds of work, but
I provide for limiting or controlling the length of the stitches by using in
combination with the aforesaid "let-off" device h of the primary slide ba
regulating contrivance as follows, that is to say:-I arrange in combination
with the two-armed bar or piece h (which is pivotted to the rod i, whereby
the said primary slide receives motion from the operating cam d) a regulating
screw provided with nuts k, with which the stops c¹ are arranged to come in
contact, and which may be adjusted to allow the said slide free movement
to the full extent permitted by the aforesaid yoke fand cam e, and thereby cause
the machine to make long stitches; or it can be set to limit the stroke of the said
slide when it is desired to sew with short stitches. This regulating screw j does
not interfere with the action of the said let-off device. I prefer that the said screw
should have right and left hand threads, the nuts being arranged thereon, as shown.

page_text: 1, 2, represent the spring, which constantly tend to force the piece h into the position
shewn in Figure 2.
For regulating or altering the proportion of the number of stitches in the sides
with regard to those in the bars, I provide means for adjusting the circumferential
distance or length of the aforesaid projection or shoulder e¹ of the cam e of the
detaining device. For this purpose I construct the said cam in two parts in the
form of jaws. e*, e*, which clip or surround the axis or shaft of the said cam, as
shewn in Figures 3 and 4, and each of which is formed with an eye or boss e³, so
that it will be kept in place on the said shaft, which serves as the fulcrum of the
said jaws. At their extremity the said jaws have between them a spring m, which
tends always to force and keep together the two parts of the jaws forming the
projection e¹. But between these two parts I insert a taper piece n, which has a
screw shank n' fitted in the block or cam g, so that by turning this shank the
said taper piece may be forced inward, thereby separating the two halves e", e*, of
the cam e at this part and increasing the extent of surface of the projection e¹. Or
I may use any other suitable pieces made taper to fit and slide between the inner
surfaces of the said parts of the projection e¹. This sliding taper or wedge shaped
piece may in some cases be connected with a separate screw, whose head projects
in a convenient position to permit its manipulation. But in either case the
adjustment of the said taper or wedge shaped piece in one direction or the other
endwise or in line with the axis of the said cam e, will increase or dimimish the
length or extent of the said projecttion or shoulder e¹, and the proportion of the
same to the length of the low or small portion e* of the said cam. And as the side
stitches of the button hole are formed during the time the projection e¹ of the
cam e is presented to the projections f₁ of the yoke, it will be seen that by providing
for varying the length or extent of the said projection I can vary the number
of stitches in the sides in relation to the number of those in the bars of the button
hole.
Having thus fully described the said Invention as communicated to me by my
foreign correspondent, and the manner of performing the same, I wish it understood
that I do not claim separately or irrespectively of the improvements herein
specified, the employment in a sewing machine of the detaining device or the let-off
device in combination with the slide of the cloth clamp, but I clain,-
.
First. The improvements comprising the modification in the detaining device in
combination with the let-off device provided with a regulating screw, whereby
the length of the stitches may be varied, substantially as and for the purpose
specified.
Second. The improvements in the detaining device, whereby I make provision
for increasing or diminishing the length or extent of the projection or high surface
of the cam, and thereby varying the proportion of the number of stitches in
the sides to that of the stitches in the ends or bars of the button hole as above
specified.
Third. The combination with the primary slide of the cloth clamp, the aforesaid
improved devices both for regulating the length of the stitches and for varying
the proportion of the number of stitches in the sides and bars, substantially as set
forth.
In witness whereof, I, the said Harry Mills, have hereunto set my hand