Guide for withdrawing yarn from a filling measuring and supplying device for a loom

An improved guide for filling yarn in its travel to an inserting device for a loom from a yarn measuring and supplying device having a circular rotatable yarn winder provided with a circular array of yarn-catching fingers along a peripheral edge thereof. The guide comprises two concentric axially-spaced rings, one large and one small, with the larger adjustably mounted coaxially with but spaced from the fingers and having an inner diameter slightly smaller than the outer diameter of the winder edge. The smaller ring is spaced from the larger on the side opposite the winder to reduce ballooning of the withdrawn yarn.

FIELD OF THE INVENTION 
This invention relates to shuttleless looms and, more especially, to looms 
wherein the filling yarn is inserted by an air jet. In greater 
particularity, the invention relates to an improved guide for the filling 
yarn in its travel from a yarn measuring and supplying device to the yarn 
inserting device. 
BACKGROUND OF THE INVENTION 
The yarn measuring and supplying device for a known type of air jet loom 
includes a rotatable yarn winding drum to which yarn is fed tangentially 
through a radial slot in a cylindrical drum cover from a suitable supply, 
e.g., a package, and from which yarn is withdrawn laterally or endwise 
from one end of the drum. Telescoped into that end of the drum is a short 
cylinder having along the corresponding end edge a circular array of 
yarn-catching fingers extending parallel to the cylinder axis. The 
cylinder is of slightly smaller diameter than the drum and is rotatable 
therewith but also is reciprocable on its axis to extend the fingers out 
of the drum into catching engagement with the withdrawn yarn end to wind 
yarn onto the drum, or retract the fingers at least partly into the drum 
to release the wound yarn for withdrawal from the corresponding end of the 
drum. Secured to the cylindrical drum cover over the fingers is a yarn 
guide end cover plate, somewhat concave on its inner side and having a 
central circular opening aligned with the axis of the drum. The inner side 
of the cover plate is formed with an annular groove or channel into which 
the circular array of fingers loosely fits when extended. 
In operation of such a measuring and supplying device, the fingers are 
extended to catch the yarn, the drum and fingers rotated to wind a 
predetermined length of yarn onto the drum, rotation of the drum and 
fingers stopped, the fingers retracted to release the yarn withdrawal end, 
and the measured length withdrawn through the central opening in the end 
cover plate by the inserting device. The cycle is then repeated. 
While such yarn measuring and supplying device is in use on looms presently 
in commercial operation, it possesses disadvantages. In particular, it has 
a strong tendency to break or otherwise damage yarn filaments, especially 
glass or fiberglass filaments, by the abrupt bends imposed therein in 
being pushed into the annular channel in the end cover plate. Moreover, 
unless the yarn-catching cylinder is carefully fitted and adjusted, with 
relation to the end cover plate, and vice-versa, the yarn-catching fingers 
engage and rub against the end cover plate with resulting damage to one or 
both. Moreover, considerable jump rope motion, or the phenomenon known as 
"ballooning", of the yarn occurs in its travel from the central hole in 
the end cover plate to the inserting device, which may be an air jet 
nozzle. Such ballooning not only tends to damage the yarn PG,4 but also 
to wear excessively the yarn entrance of the inserting device. Further, 
the end cover plate is relatively expensive. 
U.S. patents relating to somewhat comparable yarn measuring and supplying 
devices are: 
Bucher, U.S. Pat. No. 3,276,484, Oct. 4, 1966 
Bucher, U.S. Pat. No. 3,411,547, Nov. 19, 1968 
Hosono et al, U.S. Pat. No. 3,674,057, July 4, 1972 
Tannert, U.S. Pat. No. 3,709,444, Jan. 9, 1973 
Rosen, U.S. Pat. No. 3,904,141, Sept. 9, 1975 
The devices disclosed in these patents, however, possess one or more of the 
disadvantages described above, and especially tend to cut or break glass 
yarn filaments. 
SUMMARY OF THE INVENTION 
Accordingly it is an object of this invention to provide an improved yarn 
withdrawal guide for a yarn measuring and supplying device of the type 
described above which takes the place of, but is less expensive than, the 
end cover plate, which minimizes damage to or breakage of yarn filaments, 
especially glass yarn, and which reduces ballooning of the yarn in its 
travel from the measuring device to the inserting device with consequent 
less wear on the yarn entrance of the latter. 
The foregoing objects are accomplished by replacing the end cover plate 
with two yarn guide rings both concentric with the winding drum. One of 
the rings is larger than the other and is fixedly mounted adjacent but in 
spaced relation to the yarn-catching fingers when they are extended. This 
larger ring is of an inner diameter slightly smaller than the outer 
diameter of the circular array of the fingers. The other smaller ring is 
spaced outwardly of the other, along the line of travel of the yarn to the 
inserting device, to reduce ballooning of the yarn during such travel. 
Other objects and advantages of the invention will become apparent from the 
following detailed description and accompanying drawings, in which:

DETAILED DESCRIPTION OF THE INVENTION 
Referring now to FIGS. 1 and 2 of the drawings, there is shown a prior art 
device 10 for measuring and supplying predetermined lengths of filling 
yarn 12 to a filling yarn inserting device, e.g., an air jet nozzle 14, 
for a loom (not shown). The device includes a cylindrical winding drum 16 
mounted on a drum winding shaft 18 driven by known means (not shown) in 
timed relation to the movements of the loom. Filling yarn 12 is supplied 
to the drum 16 tangentially through a slot 20 in a cylindrical drum cover 
22. The cover 22, of less length than the drum 16, surrounds an end 
portion of the drum and is mounted to a fixed supporting structure (not 
shown) by bracket arms 24. Yarn 12 is fed to the measuring device 10 from 
a suitable supply, e.g., a package (not shown) through the nip between the 
uncovered surface of the drum 16 (at one side of the cover 22) and a yarn 
feed wheel 26 which rides on the drum 16. The wheel 26 is journalled on a 
stub shaft (not shown) carried by a feed wheel lever 28 urged by a spring 
30 to hold the wheel 26 against the drum 16. From the nip, the yarn 12 is 
led through the eye 32 of a filling guide 34 to the slot 20. 
Telescoped into the covered end of the drum 16 for reciprocation axially of 
the drum is a short cylinder 36 having a circumferential array of yarn 
catching teeth or fingers 38 projecting longitudinally from the outer end 
of the cylinder 36 parallel to its axis. One side edge of each tooth 38 is 
generally parallel to the axis of the cylinder 36, while the other is 
inclined rearwardly relative to the direction of rotation of the cylinder 
36, as shown by the arrow in FIG. 2, which is rotatable with the drum 16. 
At its other end, the cylinder 36 is provided with an end plate 40 
coaxially fastened, as by a screw 42, to the end of a rod 44 which extends 
through the shaft 18 and is rotatable therewith, such as being splined 
thereto. The rod 44 also in reciprocable within the shaft 18 to retract 
the fingers 38 partly within the drum 16 or extend them outwardly beyond 
the corresponding end of the drum into a position to catch yarn 12, as 
later described, so that rotation of the drum 16 and cylinder 36 will wind 
yarn from the slot 20 onto the drum 16. The rod 44 is reciprocated by 
known means (not shown) in timed relation to rotational movement of the 
drum 16. Preferably a conical cover plate 46 has a base flange, secured, 
as by screws 48, to the end plate 40 of the cylinder 36. 
Detachably fastened to the cylindrical cover 22 over the corresponding ends 
of the drum 16 and the cylinder 36 is a frusto-conical yarn guide cover 
plate 52 having a central circular aperture 54. At this larger end, the 
plate 52 has an annular recess 56 which loosely receives the fingers 38, 
when extended. 
In operation, yarn 12 is trained through the slot 20 in the cylinder cover 
22 and out through the central aperture 54 in the yarn guide cover plate 
52 to the inserting device 14. The latter cover plate 52 is detached from 
the cylindrical cover 22 to facilitate this maneuver and the replaced. 
When the loom is in operation, the rod 44 moves to extend the fingers 38 
to catch the yarn 2 on the edge of a finger parallel to the drum axis, the 
drum 16 and cylinder 36 rotate a given amount to wind a predetermined 
length of yarn onto the drum 165, as shown in FIG. 2, the fingers 38 
retract, and the inserting device 14 pulls the measured length of yarn 
laterally or endwise off of the drum 16 through the central aperture 54 in 
the yarn guide cover 52, the trailing end of the length of yarn being 
clamped between the feed wheel 26 and the drum 16. 
During this sequence of operations, it will be seen that the yarn 12 
traverses a tortuous path having abrupt bends therein, i.e., into and out 
of the annular recess 56 in the yarn guide cover plate 52. When the yarn 
12 is of glass or fiber glass such bends cause broken filaments with 
resulting poor quality fabric. Moreover, the yarn 12 revolves about the 
circular edge of the aperture 54 in the yarn guide plate 52 as it exits 
through the aperture with a jump rope motion that causes the yarn to 
balloon unduly as it travels to the inserting device 12. Such undue 
ballooning has a damaging effect on yarn, especially glass yarn, as well 
as causing considerable wear on the yarn entrance of the inserting device 
14. 
Moreover, unless the yarn guide cover plate 52 is carefully constructed and 
installed, the fingers 38 tend to rub against the side walls and/or bottom 
of the annular recess 56 in the plate with resulting damage to both, even 
necessitating replacement upon occasion. 
Referring now to FIGS. 4 and 5, there is shown a yarn measuring and 
supplying device 60 embodying this invention. All the elements or 
components of the device 60 are the same as those of the prior art device 
10 except the yarn guide end cover plate 12 is eliminated. In its place is 
a yarn guide 62 in the form of two coaxial, axially-spaced rings, one 
large 64 and one small 66, mounted coaxially with the drum 16. The larger 
ring 64 is located closely adjacent the tips of the circular array of 
fingers 38, when extended, and has an inner diameter slightly less than 
the inner diameter of the circular array. The smaller ring 66 is spaced 
outwardly of the larger ring 64 and has an inner diameter considerably 
less than that of the larger ring. The outer ring 66 is secured, as by 
welding or brazing, to the inner ends of the inturned legs of a number of, 
e.g. three, L-shaped mounting brackets 68. The ends of the other legs of 
the brackets 68, which extend parallel to the drum axis, are slotted for 
the reception of screws 70, or the like, for adjustably mounting the 
brackets 68 on the brackets 24 which carry the cylindrical drum cover 22. 
The larger ring 64 is secured to the brackets 68 by arms 72 extending 
parallel to the axis of the ring 64 between the ring 64 and the inturned 
legs of the brackets 68. The arms 22 are secured to the ring 64 and the 
brackets 68, as by welding or brazing. 
The operation of the device 60 is the same as that of the prior art device 
10 except that the measured length of yarn is pulled endwise off of the 
drum 16 through the rings 64 and 66. It will be noted that the yarn 12 
travels off the drum 16 to the larger ring 64 in a generally straight path 
with no tortuous bends, thus minimizing or eliminating yarn damage and 
broken filaments. Further, the adjustable mounting of the brackets 68 
enables proper positioning of larger ring 64 adjacent but in spaced 
relation to the fingers 38 when extended with no possibility of engagement 
and rubbing of the ring 64 by the fingers, thus eliminating that source of 
damage to the fingers and the yarn guide 62. 
The location of the smaller ring 66 nearer the inserting device 14 reduces 
ballooning of the yarn 12 in its travel between the ring 66 and the device 
14, thus reducing both yarn damage and wear in the yarn entrance of the 
inserting device. 
Lastly, the yarn guide 62, including both rings 64, 66 and the brackets 68 
is less expensive to make than the yarn guide end cover plate 52 of the 
prior art. 
It thus will be seen that the objects and advantages of this invention have 
been fully and effectively achieved. It will be realized, however, that 
the foregoing specific embodiment has been disclosed only for the purpose 
of illustrating the principles of this invention and is susceptible of 
modification without departing from such principles. Accordingly, the 
invention includes all embodiments encompassed within the spirit and scope 
of the following claims.