Improvements in Loop Stitch Sewing machines:
Year: 1896

page_text: Date of Application, 28th. Apr., 1896-Accepted, 6th, June, 1896
COULL. WE ALL K
[Communicated from abroad by WILLIAM HARRIS BOYER.and THE AMERICAN
SPECIAL MACHINE COMPANY, LIMITED, Manufacturers, both of 47 Leonard
Street, New York, U.S.A.]
Improvements in Loop Stitch Sewing machines:
I JOHN. WILLIAM MACKENZIE of the Firm af Wheatley and Mackenzie
Engineers and Patent Agents of 40.Chancery Lane; in the Cauntyof London
do hereby declare the nature of this invention andeinr what manner the:sameria to
be performed, to be particularly described andrascertained in and, by the following
statement-:-
My invention relates to sewing machines and more especially to that class in
which a looper on the. underside of the cloth plate is combined with a vertically
reciprocating needle carrying the upper thread, and the object of the invention is
to provide an improved means for imparting to the looper the movement necessary
to produce in connection with the:needles the desired, stitch, which, in the present
case, is a double loop stitch,.such as-is. characteristic. of the well. known. Grover
and Baker sewing machine.
The invention is herein shown as applied to a machine in which three needles
and three loopers are used; designed for such work as corset-sewing; but it will be
understood that the invention may be employed with a single needle and single
looper as for ordinary line sewing or with any other number of needles and loopers
that may be desirable.
The invention consists, therefore, in the matters hereinafter described. and
referred to in the appended elaims:
In the accompanying drawings which illustrate-the-invention;-.
Figure 1 is a front elevation of so much of a sewing machine as is sufficient for
a correct understanding of my invention;
Figure 2 is a transverse section of the same;, and
Figure 3 is a perspective view.
In these drawings, A represents the bottom-plate of the machine: supporting the
cloth-plate A', of usual construetion; N'is the needle bar-herein-shown as provided
with three needles n, P is the presser-foot and D the feed dog, its frame D" being
forked and operated by the-cams'd; d'on the-main shaft S, this nain-shaft. being
herein shown as extending- longitudinally of the machine; the feed being, at right
angles to the axis of said-shaft:
Arranged transversely of the machine or at right angles to the main shaft is a
bar or shaft B having-bearings in the journals b, bsupported on the frame of the
machine. A slight reciprocation is given this shaft B in the direction of its length,
by means of the eccentric E carried on the shaft S between the cams d, d, and
working in the slot formed by the forks in the frame D', which eccentric carries
the connecting rod e having a ball on its end: The shaft or bar B is hollow, its
end adjacent the shaft S being contracted to form shoulders g rounded off to act as
a seat for said ball f, the inner portion of the bar or shaft B from the shoulders g
enlarging outwardly to allow of the perfectly free movement of the connecting
rode when actuated by the eceentric. To'afford a seat for the front end of the
ball fa screw threaded piece is inserted into the outer end of the shaft or bar B
having a socket i in which the ball fits. Fixed upon the bar or shaft B is a looper

page_text: carrier C herein shown as provided with three loopers c co-operating with the
needles n to form the stitches. To give the. desired oscillatory movement to the
loopers a connecting rod R is freely jointed to the looper carrier, and at the other
end said rod is attached to and reciprocated by a moving part of the machine, such
as the needle lever. It will thus be seen that in the movement of the main shaft
the shaft B will reciprocate in the direction of its length, and at the same time
will rock back and forth in its bearings on the ball f as a pivot.
. While the main shaft is herein shown as extending longitudinally of the machine
and the shaft or bar B at right angles thereto, or transversely to the machine, it
will be obvious that this arrangement of parts may be reversed. While also the
shaft or bar B is herein shown as hollow and connected to the main shaft, and
deriving both reciprocatory and oscillatory movements in a certain specified
manner, it will be understood that I do not wish to be limited absolutely to such
an arrangement as changes in such construction might be made, and, further-
more, various other minor modifications and changes in the construction of the
various parts may be made without departing from the spirit of my invention.
As will be apparent, the loop taking movement of the looper is of necessity
longer than the needle avoiding movement. By making the rocking of the carrier
give the looper its loop taking movement, and the sliding of the carrier its needle
avoiding movement much friction is avoided thereby making the present
arrangement of considerable practical advantage when applied to a high speed
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,
1. In a sewing machine the combination with a thread,carrying looper having
oppositely extending journals, of fixed bearings for said journals, complemental
stitch forming mechanism, and -mechanism for imparting to the looper a positive.
loop taking movement in the arc of a circle, and a positive needle avoiding.
movement in a right line whereby drag on the needle thread is prevented and
liability of the looper striking the needle is avoided; substantially as described.
2. In a sewing machine the combination with a needle, of an under thread
carrying looper, trunnions bearing in fixed supports on the machine frame
constituting the center of motion of said looper and extending oppositely to each
other and at an angle to the longitudinal axis of the looper, and means for
positively operating said trunnions to give a forward and backward loop taking
and loop leaving movement and positive means for sliding said trunnions axially
in their bearings to give the looper a needle avoiding movement; substantially as
described.
3. In a sewing machine the combination with the needle and means for operating
the same, of a looper, a carrier therefor, said carrier being mounted in and being
free to slide and to rock in bearings, means for sliding and rocking said carrier,
said sliding movement being at right angles to the length of the looper whereby
the longer loop taking movement of the looper is given by the rocking movement
of the carrier and the shorter needle avoiding movement of the looper is given by
the sliding movement of the carrier and friction. thus reduced; substantially as
described.
4. In a sewing machine the combination with a thread carrying needle and
a feeding device having movement in a defined path, of a thread carrying looper,
the longitudinal axis of said looper being at an angle to the line of feed, means for
giving to said looper four movements, viz., a positive loop taking and positive loop
leaving movement at an angle to the line of feed, and two positive needle avoiding
movements, two of said movements being in the arc of a circle and the other two
being bodily movements in a right line, across the line traversed by the looper in.
its first named movements; substantially as described.

page_text: 5. In a sewing machine, the combination with a needle, of a looper having
journals arranged on opposite sides of one of its axes, fixed bearings in which said
journals are mounted and positive means for sliding and rocking said looper';
substantially as described.
6. In a sewing machine, the combination with the needle, of a looper, a carrier
for said looper provided on its opposite sides with journals mounted to slide and to
rock in bearings and means for positively sliding and rocking said carrier in such
bearings; substantially as described.
7. The combination in a sewing machine of a main shaft, a relatively short
shaft arranged adjacent the forward end of the main shaft and with its axis.
transverse to the axis of the main shaft and having pivotal bearings axially
movable in fixed supports, a thread carrying looper secured to said shaft between.
its bearing points and positively operating connections between the main shaft and
looper shaft whereby said looper may be reciprocated laterally bodily and oscillated
horizontally; substantially as described.
8. The combination in a sewing machine of a main shaft, an axially movable
shaft supported in bearings on the machine frame, a reciprocating needle, an
eccentric and universal joint connection between the main shaft and axially movable
shaft whereby the latter is reciprocated, a looper secured to said axially movable
shaft between the bearings of said shaft, and means for oscillating said shaft in its.
pivotal bearings; substantially as described.
9. The combination in a sewing machine of a main shaft, an axially movable
shaft supported in bearings on the machine frame and arranged at right angles to
the main shaft, a reciprocating needle, an eccentric and universal joint connection
between the main shaft and said axially movable shaft whereby the latter is
reciprocated, a looper secured to said shaft and adapted in the reciprocation
thereof to move from side to side to avoid the needle, and means for oscillating said
shaft on its pivotal bearings to give the forward and backward oscillation to the
looper; substantially as described.
10. The combination in a sewing machine with a driving shaft, of an axially
movable shaft arranged at right angles thereto and supported in bearings on the
machine frame a looper rigidly fixed to said shaft between the pivotal points
thereof, an eccentric and ball and socket connection between the driving shaft
and the axially movable shaft whereby bodily movement in a right line is given
said shaft and looper and means for oscillating said axially movable shaft ;
substantially as described.
11. A sewing machine comprising a main shaft, a second shaft arranged with
its axis at right angles to the axis of the main shaft and journalled in bearings
on the machine frame, a looper fixed to said shaft between the bearing points,
an eccentric and universal joint connection between the main shaft and the second
shaft whereby the second shaft is reciprocated and the looper moved bodily in
one direction, and an independent driving connection between the main shaft and
second shaft whereby the looper is oscillated; substantially as described.
12. A sewing machine comprising a main shaft, a hollow shaft journalled in the
machine frame, a looper secured to said hollow shaft, an eccentric on the main
shaft, and a connecting rod having on one end a ball fitting within the hollow
shaft and universally jointed thereto, and complemental stitch forming mechanism;
substantially as described.
13. A sewing machine comprising a main shaft, a hollow shaft axially movable
in fixed supports on the machine frame, a looper secured to said hollow shaft
between the fixed supports, said hollow shaft having an inwardly tapering recess
at one end, forming a shoulder, a socketed piece set within said hollow shaft and
the connecting rod e having the ball on its inner end resting between the socketed
piece and the shoulders of the tapering recess and complemental stitch forming
mechanism; substantially as described.
14. A sewing machine comprising a looper, a carrier to which said looper is

page_text: secured having oppositely extending trunnions mounted to rock on fixed bearings
secured to the machine frame and located between, said. fixed bearings, and means
for rocking and sliding said carrier; substantially as described.
Dated this 28th day of April 1896
WHEATLEY & MACKENZIE,
40 Chancery Lane, London, W.C., Agents.