Improvements in Sewing Machines for Producing Hem-stitching and Veining.
Year: 1888

page_text: COMPLETE SPECIFICATION.
Improvements in Sewing Machines for Producing Hem-stitching
and Veining.
I, DUNCAN MCGLASHAN, of the Clyde Sewing Machine and Tool Works, Paisley,
Scotland, Mechanical Engineer 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, reference being had to the accompanying two sheets
of Drawings, and to the letters and figures marked thereon, that is to say :-
The improvements forming the subject of my present invention have for object the
production of perfectly well formed open stitches, technically called hen-veining and
hem-stitching in linen, cotton, and other material with means of increasing or
diminishing the size of such stitches at pleasure.
In the sewing machine to which I have applied my improvements, the needle has
the well known upward and downward movements combined with movements from
right to left, and from left to right, the said needle sliding, for that purpose, in a slide
which receives, at the proper moment, definite angular movements alternately from
right to left and from left to right in a plane perpendicular to the direction in which
the work is moved forward.
The presser foot in co-operation with the complex movements of the needle receives,
besides the requisite upward and down movements, forward and backward
movements in such manner that the needle returns into each of the stitches it has
previously made; but without falling exactly into the same place in the said stitch,
so that the needle after having pierced the cloth at a certain point, and after the
presser foot has imparted a forward and a backward movement to the cloth, shall fall
exactly in the centre of the space already half formed.
In order that the cloth may be constantly held when the presser foot is raised, I
employ a supplementary cloth presser which participates in the movements of the
lever which effects the upward and downward movements of the needle, and which

page_text: cloth presser rises when the presser foot advances or recedes, and falls when the
presser foot rises.
The cam which imparts the requisite oscillations to the frame of the needle carrier
is formed so that the extent of these oscillations can be varied in such a manner that
the needle moves the same distance on each side of the perpendicular whether the
total movement be long or short.
In the same way the cam which imparts the backward and forward movements to
the feed bar is arranged so that the movements of the said feed bar can be varied.
For this purpose the feed bar is connected adjustably with a lever which carries the
friction roller, acted on by the cam, the connexion being adjustable so as to increase
or diminish the extent of the movements of the lever connected to the presser foot.
This new combination gives a practical means of varying the eccentricity of the
needle stitches so that the size of the stitch openings formed may be varied at
pleasure.
In the Drawings hereto annexed,
Figure 1 is a side view of a sewing machine with my improvements applied
thereto, the said view being taken at the needle side of the machine. Figure 2 is a
side view of the opposite side of the machine. Figure 3 is a plan. Figure 4 is an
end view partly in section. Figure 5 is a separate view of the lever or arm which
effects the simultaneous oscillations of the needle-carrier and of the needle-guide.
Figure 6 is a section of the cam shown in Figure 5. Figure 7 is a separate
view of the supplementary cloth presser in the position it assumes when raised
off the cloth by the needle lever coming in contact with its upper end. Figure 8
is a detail view of the combined levers which produce the forward and backward
movements of the presser foot. Figure 9 shows the cam which operates the levers
shown in Figure 8, and Figure 10 shows a developement of the acting surface of the
said cam. Figure 11 is a diagram showing how the stitches are formed which
constitute the open work stitching represented in Figure 12. Figure 13, 14, 15,
and 16 are detail views of a needle guide easily adjusted by the person working
the machine, and which can be applied to all kinds of machines which have moveable
needle guides in the shuttle race.
The frame A of the machine possesses no particular feature except that it is adapted
to receive and support the shafts and levers to be hereafter described. It carries the
pivot B of the frame B which forms a slide for the needle carrier a¹ to which the
needle a is fixed by means of the piece a secured by two screws. The frame B is held
during its angular movements by the head of a screw B which passes through a slot
in the head and screws into a lower and front projection of the frame.
The needle carrier a¹, which is hollowed out lengthwise, is connected to one end b¹
of a lever boscillating on the fulcrum pin of the frame, and taking at its other end
into the curvilinear groove of the cam 6x fixed on the driving shaft o.
This cam b
is not visible in Figures 1, 3 and 4 because the covering o¹ through which the lover b
passes comes in front of it in those figures. This cam, like the one y side by side
with it, and which imparts the alternate rectilinear movements to the shuttle, has no
new feature whatever."
With the frame B is formed in one piece the arched or U shaped lever or arm
(Figures 1, 3 and 5) carrying at its lower end the needle guide which partakes of
the same angular movements as the frame B round the pivot B. At c¹ the lever or
arm c is slotted and is guided by a pin e fixed in the frame A and forming on the
other side the axis or pivot on which works the lever imparting the requisite upward
and downward movements to the presser foot.
Below the guide e the lever or arm c has a projection carrying a piece c² which
bears by means of the friction roller c on the cam g fixed on an intermediate shaft h
placed parallel with the driving shaft o and connected therewith by means of the
pinion and spur wheel . This gearing is arranged in the proportion of 1 to 4.
The special supplementary cloth presser d turns on a pivot at f¹ on a support f
fixed on the face of the frame A. The cloth presser d is constantly pressed towards
the supporting surface of the cloth by means of the spiral spring d fixed at one end

page_text: to the frame and at the other to the tail of the cloth presser d. The raising of the
cloth presser d from the cloth is effected by the roller s on the lever of the needle
carrier pushing backward the tail d² when the lever brises to withdraw the needle
from the cloth.
The cloth presser d is intended to press on the cloth when the latter is released by
the presser foot and the said foot has to make an advance or recession with respect to
the cloth in order to begin a fresh stitch. The said cloth presser has no action on the
cloth when the latter is being acted on by the presser foot.
The cam g is of a special form such, that by changing the position of the friction
roller c, the angular movements of the arm c may be varied more or less so as to
vary the movements of the frame of the needle carrier from right to left and from left
to right.
The presser foot p, the claw p¹ of which works on a hinge, is of ordinary con-
struction. It is suspended by two pivots which take into cavities in the upper
part of the head. Above these pivots p² the presser foot is formed into a hook (sce
Figure 8) into which the end of the lever passes. The lever turns on the fulcrum e
and its rear end is acted on, when the machine is in motion, by the friction roller i on
the cam g. When the presser foot is raised by means of the eccentric; the front end
of the lever is raised also and its rear end is moved away so that the friction roller i
on the cam g cannot act upon it.
A spiral spring one end of which is connected to a fixed point 1 of the head of
the frame A of the machine, and the other end to the front end of the lever 1, not
only brings the said lever 7 down on to the top of the presser foot bar, but also holds
down the said foot on to the cloth when the eccentric is lowered. This spring k acts
in opposition to the roller i but yields to the action thereof so as to allow it to raise
the presser foot, but brings the latter down on to the cloth, and the lever back to its
normal position, when the roller i has ceased to act on the said lever l.
The transverse movements of the presser foot are communicated to it in the following
way-
The intermediate shaft carries the cam m (Figures 2, 3, 4, 8, 9, and 10) placed
near the cam g. The curvilinear periphery of the cam m acts on the friction roller n'
of a lever n pivotted at 2 on the frame A. The back of the lever n is formed as an
inclined plane against which bears the movable piece y carried on a slide 1 of a
lever ».
The lever is pivotied at the points of the frame, so as to be adjustable
if necessary into its position of action. A spring 3 holds the lever in permanent
contact with the lever n.
The lever is formed in one piece with an arms the two forming together a kind
of bell crank lever turning on the points 21 12. The pendent arm s embraces, by
means of its forked end s¹, the presser foot p, and communicates thereto the requisite
angular movements without interfering in any way with the upward and downward
movements.
:
By adjusting the sliding piece q so as to place it nearer to or farther from the
fulcrum of the levers the movements imparted to the latter by the cam m through
the lever n are increased or reduced. By this means the movements of the presser
foot inay be regulated as required, such movements taking place in the same direction
as that of the cloth.
The cam m is of such a form as to give to the cloth, by means of the presser foot,
the requisite movements in co-relation with the complex movements of the needle, and
to produce thereby the open stitches of the kind shown in Figure 12, namely, stitches
which are triangular in-shape, and angularly opposed to one another being separated
by an intermediate line of stitches xx.
Figures 9, 10, 11, and 12 illustrate the co-relative movements of the presser foot
and of the needle. For example, the needle having just made a stitch at o on the
right side of the line arises and is carried to the left of the line a. Simul
taneously the cloth is advanced so that the needle next makes a stitch at 1 (Figure 11).
The needle then rises and the cloth is brought back, and the needle then makes a

page_text: stitch at 2 and then rises again. The needle is then carried to the right of the line,
the cloth is brought forward and the needle makes a stitch at 3. The needle then
ascends, the cloth is drawn back and the needle descends to make a stitch at 4.
When the stitch at 4 is finished the presser foot rises from the cloth and returns to
the position for commencing a fresh set of four stitches. The needle again rises and
is carried to the left, the cloth is simultaneously advanced and the needle then descends
forming a stitch at 11. The same series of operations are repeated, the needle
doubling successively the stitches previously made but so that the needle always falls
behind the stitches previously made, which causes the threads of the cloth to be
drawn more completely together and to enlarge the openings in the stitches already
made.
The presser foot is operated as follows:-
Having brought forward the cloth when the point o of the cam is acting on the
lever the presser foot draws the cloth forward, the neelle enters the cloth and forms a
stitch at 1 (Figure 11) then the presser foot draws back the cloth to a shorter distance
than it before pushed it forward, the needle again enters the cloth forming a stitch
at 2, then the presser foot moves the cloth forward, the needle meantime has been
moved across to the other side of the line a a, it enters the cloth and forms a stitch
at 3, then the presser foot again moves the cloth backwards to a less extent than it
previously moved it forward, the needle again descends, forms a stitch at 4, and the
presser foot is lifted from the cloth the point o of the cam having returned to the
same position as at the beginning of the set of operations.
It now remains to describe the needle guide which is devised so as to allow of its
position being easily adjusted with reference to the movements of the needle a.
Figures 13, 14, 15, and 16 illustrate this part of my invention.
On the support t which is secured to the lower end of the lever or arm c is secured
the needle guide v by means of a sort of split ball and socket joint v forming part of
the said needle guide. The ball of this joint is drilled and tapped to receive a screw u
the screwing up of which tends to separate the split parts. Washers ww placed
one at each side of the ball complete the ball and socket joint which is fitted
into a slot in the support t. By this arrangement the needle guide v
can be
raised or lowered, and its position easily adjusted with reference to the needle, as it
is only necessary to slacken the screw u to allow the needle guide to slide forward or
backward to the right or to the left. This construction is applicable to all kinds of
sewing machines having a moveable needle guide in the shuttle race.
By varying the cams and gearing the machine can be readily adapted as a hem-
stitch machine.
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 -
First In a sewing machine for making open stitches of embroidery, the use of a
supplementary cloth presser d, the movements of which are connected with those of
the lever, which imparts the upward and downward movements to 'the needle guide,
the object of the said cloth presser being to hold the cloth in place when the presser
foot is raised therefrom, as hereinbefore described, and illustrated in Figures 1, 2, 3,
and 7 of the Drawings hereto annexed.
Second-In a sewing machine for making open stitches, the combination of the
levers rs and n with the cam m for the purpose of imparting to the presser foot
differential forward and backward movements of adjustable range, as hereinbefore
described, and illustrated in Figures 1, 2, 3, 4, and 8 of the Drawings hereto
annexed.
Third In a sewing machine for making open stitches, the combination of the
lever for moving the needle upwards and downwards, the lever or armi c for
imparting variable angular movements to the needle, the supplementary cloth presser d
actuated by the lever b, the lever moving the presser foot upwards and downwards,

page_text: and the levers rs, and n and the cam m for imparting to the presser foot variable
backward and forward movements in combination with the upward and downward
movements of the same, as herein before described, and illustrated in Figures 1 to 12
of the Drawings hereto annexed, and for the purpose specified.
Fourth In a sewing machine having a movable needle guide in the shuttle
race, the use of a split ball and socket joint for the purpose of fixing the needle
guide to its support t, as hereinbefore described, and illustrated in Figures 13 to 16
of the Drawings hereto annexed.