IMPROVEMENTS IN LOCK STITCH SEWING MACHINES
Year: 1884

page_text: COMPLETE SPECIFICATION,
I, WILLIAM PHILLIPS THOMPSON, Fel. Inst. P. A., of.the Agency for Foreign
Patent. Solicitors, 6, Lord Street, Liverpool, in the County of Lancastor, and,
323 High Holborn, in the County of Middlesex, Civil Engineer do hereby declare
the nature of the said invention for "IMPROVEMENTS IN LOCK STITCH SEWING
MACHINES " 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, operated directly by hand, and its
main object is to produce a simple, convenient and efficient lock-stitch hand sewing
machine of such construction that the stitch forming and feeding mechanisms will
be automatically operated from the movements of the handles by which it is held.
In the drawings,
Fig. 1 is a side elevation of the machine with the needle elevated and the
bousing forming the work plate and the shuttle race in section.
Fig. 2 is a view from the side opposite to that seen in Fig. 1 showing the needle
depressed to its lowest point.
Fig. 3 is a partial plan view, the needle carrying arm being removed.
Fig. 4 is a perspective showing in detail the feed or "spacer" and its immediate
connections, and
Fig. 5 is a perspective showing in detail a modification of the device.
A and A' are two levers pivoted together as shown or in any other suitable
manner. These levers are normally held apart by a spring B. A' is the needle
carrying lever, the curved needle C being secured to its forward end by a set
screw, as shown. The take-up lever D is pivoted to the lever A¹, at d; it is also
connected by a link with the lever A. It is desirable, that the take-up lever
should remain stationary with respect to the needle carrying lever at two different
times in the operation of the machine, once before the needle has entered the work
to prevent any slack from getting in the way of the needle, and once to allow the
shuttle to pass through the loop of the needle thread. This function is secured for
the take-up lever, by making a slot d in the link dat its point of attachment to
the lever A, thus providing for the needed loss of motion.
The lever A carries a post E upon which the sleeve F is mounted having the
cam faced flukes or flanges f. The shuttle lever G formed on or attached to the
D
11

page_text: sleeve F is preferably made in two parts so as to be longitudinally adjustable by
means of slots and set-screws, as shown, or other convenient means. H is the
shuttle carried by the lever G. A housing A2 is supported on the lever A and its
front wall forms the shuttle race. A work-plate As covers the housing and
has a curved slide a³ which may be removed for the insertion or removal of the
shuttle.
The means for operating the shuttle lever, besides those already mentioned, are
two arms t t¹ attached one to each side of the lever A¹ and so arranged that their
points or toes are located one behind each fluke or flange f. By this construction,
when the two levers A. and A' are caused to approach each other in the operation
of the machine, the point s of the arm t will press forward one of the flukes fand
cause the shuttle lever G to be moved in one direction, and when the levers are
released and separated by the action of the spring B the points of the arm t¹ will
act similarly on the other fluke f and turn the lever G in the opposite direction.
The feeding mechanism is constructed as follows:
In a frame I attached to the work plate is mounted a shaft J having a crank j;
one of the bearings of the shaft J is a yoke or crotch, as shown in Fig. 4. Extending
from tlie crank to the lever A' is a link L 'pivoted to the crank and secured to
the lever by a slot and set-screw attachment: A rod or pin Mattached to the
lever A¹ is arranged to strike against and depress an extension J' of the shaft J
and thereby raise the opposite end of said shaft together with the attached feed or
spacer" O. A spring n normally presses the feed or "spacer" against the
15
fabric.
The operation of the feeding mechanism is as follows':
On the approach of the levers, when the spring B is compressed, the set screw p
moves downward in the slot.pl until it reaches the bottom thereof when the link L
is depressed carrying with it the crank ; and thus swinging the shaft I in its
bearings and moving the feed backward. Before, however, the crank is moved,
the rod or pin M. strikes the extension J' and raises the feed or "spacer" O out of
contact with the work. In the reverse movement of the levers, the pin or rod.M
is first removed from the extension J', and afterwards the shaft J is swung and the
feed moved forward while pressed against the fabric. It will be observed that the
feeding surface has the well known 'four-motion movement.
An adjusting screw q serves to regulate the operative length of the slot p¹ and
thereby the length of the feed and of the stitch.
In Fig. 5, is shown a chain stitch mechanism which may readily be substituted
in the place of the shuttle carrying-arm and shuttle of the lock-stitch machine.
In this construction G is a vibrating loop-taker instead of a shuttle-lever.
Having now particularly described and ascertained the nature of the .said
invention as communicated to me, and in what manner the same is to be performed,
I declare that what I claim is:
1. The combination with two hand levers, of a needle carried by one of the said
levers, a shuttle race and a shuttle lever carried by the other of the said lovers,
and mechanism, connected with the said levers, for operating suid shuttle-lover,
substantially as described.
2. The combination with two hand levers, of a needle carried by one of the said
levers; a feeding device supported upon the other of the said levers, and mechanism
for imparting a four motion movement to said feeding device to advance the work
when the needle is out of the same, substantially as described.
3. The combination with two hand levers, of a needle and a take-up carried by
one of the said levers, a shuttle race and a shuttle lever carried by the other of the
said levers, and mechanism connected with them for operating said take-up and
shuttle lever, substantially as described.
4. The combination of the levers A and A', spring B, housing A³, and shuttle
lever G supported on the lever A, with mechanism for operating said shuttle lever
from the lever A¹, substantially as set forth.

page_text: 5. The combination with the lever A. and A', of the take-up lever D pivoted to
the lever A¹, and means for operating said take-up lever intermittingly from the
lever A, substantially as described.
6. The combination with the levers A and A', of the take-up lever D and link ď³,
substantially as set forth.
7. The combination with the operating levers A, A¹, provided with arms t, t¹, of
the horizontally vibrating lever provided with the flukes or cams f, f.
8. The combination of the levers A, A¹, having cam faced arms t, t¹, the
horizontally vibrating lever having the flukes or cams f, f, and the shuttle,
substantially as set forth.
9. The combination with the hand levers A A¹, of a feed or spacer, and
inechanism for tilting the feed shaft and for imparting an oscillating motion
thereto, substantially as described.
10. The combination of the hand levers A. A', the feed, the link L, the rod M,
and the spring n, substantially as described.
11. The combination of the levers A A¹, the feed provided with extension and
crank arm, the link L, the rod, and the spring, substantially as described.
12. The combination with an oscillating feed, of the slotted operating link L,
provided with means for regulating the length of the stitch, substantially as
described.
13. The combination with an oscillating feed, of the slotted operating link L
provided with set screw q for regulating the length of the stitch, substantially as
described.
200
1001
WM P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool,
Agents for the Applicant.