Threading arrangement for a sewing machine

A thread tensioning module and a cover for a thread holder and cooperating take-up are mounted adjacent to one another in a front opening in the bracket arm housing of a sewing machine. The module and cover form interconnecting thread receiving slots in the bracket arm opening providing for the movement of thread into thread tensioning mechanism carried by the module and into the thread holder as the machine is threaded by an operator.

DESCRIPTION 
BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The invention is directed to a threading arrangement for a sewing machine. 
2. Description of the Prior Art 
A sewing machine operator must pass thread through tensioning mechanism and 
a take-up before sewing operations can be satisfactorily performed. The 
threading of such sewing instrumentalities can be a tedious task, and if 
not properly performed leads to defective stitches. Various arrangements 
have been developed to simplify the threading of a machine, however, they 
have generally complicated the construction of a machine to a prohibitive 
extent or have proved to be unreliable in use. 
It is a prime object of the present invention to provide a sewing machine 
with an improved threading arrangement effective to reliably assure the 
proper threading of sewing instrumentalities on the machine, and effective 
by its appearance to make the manner of its use readily apparent to a 
machine operator. 
It is another object of the invention to provide a sewing machine with a 
simplified bracket arm assembly effective to define a self-evident path 
for sewing thread on the machine, and to assure the movement of thread 
into both thread tensioning mechanism and a thread handling device. 
Other objects and advantages of the invention will become apparent during a 
reading of the specification taken in connection with the accompanying 
drawings. 
SUMMARY OF THE INVENTION 
The bracket arm housing of a sewing machine is provided with a front 
opening. A thread tensioning module and a cover for a thread holder and 
cooperating take-up are secured to the bracket arm in such opening. Both 
the module and cover have parallel opposite sides. One side of the module 
forms a first thread receiving vertical slot with the bracket arm housing, 
and the other side of the module forms another vertical thread receiving 
slot with one side of the cover. The other side of the cover forms still 
another vertical thread receiving slot with the bracket arm housing. A 
bottom end portion of the thread tensioning module and the bracket arm 
housing for a slot interconnecting lower ends of the said first and 
another thread receiving slot. The cover and a top portion of the bracket 
arm housing form a slot interconnecting the said another and still another 
thread receiving slots. The slot at the top of the bracket arm is disposed 
relative to the thread holder to provide for the movement of thread 
through such slot into the holder. Thread tensioning mechanism on the 
module projects into the said first slot to catch thread led therein and 
around the lower end of the module.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to the drawings, reference character 10 designates the bracket 
arm housing of a sewing machine. The housing is formed with an opening 12 
which is adapted to receive a thread tensioning module 14, and a hollow 
cover 16 for a thread holder 18 and cooperating take-up 20. The bracket 
arm housing includes as an integral part thereof, a support 22 for module 
14. 
Module 14 has posts 24 and 26 which project from the rear and are 
insertable through holes 28 and 30, respectively, in support 22. The 
module is disposed in opening 12 with posts 24 and 26 projecting through 
the said openings, and spring fastener 32 and 34 are applied to the posts 
to affix the position of the module in the bracket arm housing. Cover 16 
is secured to the bracket housing in opening 12 with screws 36 and 38 
extending through slotted openings 40 and 42, respectively, in a flanged 
portion 43 of the cover and into threaded holes 41 and 45 of the bracket 
housing. 
In the secured positions in opening 12 of the module 14 and cover 16, such 
parts form in association with each other, and with the bracket arm 
housing 10 a self-evident threading path for thread to be used in sewing 
operations. As shown, the module 14 has parallel opposite sides 44 and 46, 
and the cover has parallel opposite sides 48 and 50. One side 44 of the 
module forms a vertical slot 52 in the bracket arm housing 10 with an end 
wall 54 of the housing, and the other side 46 forms a vertical slot 56 
with side 48 of the cover. Side 50 of the cover forms a vertical slot 58 
with an end wall 60 of housing 10. The lower ends of slots 52 and 56 are 
interconnected by way of a curvilinear slot 62 extending around the lower 
end of the module between the module and the bracket arm housing. Slots 56 
and 58 are interconnected by a cross over slot 64 which is formed at the 
top of the bracket arm between cover 16 and the bracket arm housing. 
Module 14 is of the kind disclosed in the copending patent application of 
A. Giamo and R. H. Larsen for "Thread Tensioning Module for a Sewing 
Machine", Ser. No. 512,849, filed July 11, 1983. As such, the module 
includes thread tensioning mechanism with thread engageable parts 66 and 
68 for applying tension to thread according to the position of a control 
knob 70. Thread engageable post 66 includes a marginal edge portion 70 
which projects beyond side 44 of module 14, and which in the secured 
position of the module in bracket arm housing 10 extends across slot 52. 
Part 66 also includes a marginal edge portion 72 which projects beyond 
side 46 of the module to extend across slot 56. Module 14 is provided at 
side 44 with an affixed thread guiding pin 74 to extend across slot 52 
near the top of the bracket arm housing. 
Cross-over slot 64 lies directly over thread holder 18, such thread holder 
being of the kind disclosed in the copending patent application of Donald 
Rodda for "Camming Arrangement for Thread Handling Device", Ser. No. 
422,770, U.S. Pat. No. 4,413,578 filed Sept. 24, 1982. The thread holder 
includes thread engageable cams 76 and 78 which bracket an elongate 
fibrous member 80 and bar 82 engaged thereby. Take-up 20 brackets the 
thread holder and is movable therealong by mechanism 84 which is connected 
to needle bar 86. The front edge 88 of slot 64 is rearward of bar 82 and 
the rear edge 90 of the slot is directly over cams 76 and 78. 
A machine with bracket arm housing 10, module 14 and cover 16 assembled as 
described is threaded with thread T from a supply spool 91 by first having 
the thread pass through a guide 94 and then into slot 52. The thread is 
then led down vertical slot 52, through curvilinear slot 62 extending 
around the lower end of module 14, up vertical slot 56, through cross-over 
slot 64, down vertical slot 58 and then through the eye 96 of a sewing 
needle 98. The thread is engaged by pin 74 in slot 52 and is caught in the 
lower end portion of the slot by marginal edge portion 70 of part 66 of 
the thread tensioning mechanism in module 14. As the thread is led about 
the module and up slot 56 the thread slides on part 66 into a position 
between the thread tensioning parts 66 and 68. After the thread has been 
disposed into cross-over slot 64 and while being moved down slot 58, the 
thread is caused to engage thread holder 18 rearwardly by the bar 82 and 
to slide into a position on cams 76 and 78, and between the fibrous member 
80 and bar 82. 
It is to be understood that the present disclosure relates to a preferred 
embodiment of the invention which is for purposes of illustration only and 
is not to be construed as a limitation of the invention. Numerous 
alterations and modifications of the structure herein will suggest 
themselves to those skilled in the art, and all such modifications and 
alterations which do not depart from the spirit and scope of the invention 
are intended to be included within the scope of the appended claims.