[0001] The present invention relates to an improved process for manufacturing socks with
hosiery machines and to a semiworked item obtained with said process.
[0002] As is known, cotton or wool socks, in particular for men, are currently generally
manufactured on circular knitting machines which provide a semiworked product, open
at the tip, which requires a subsequent finishing operation, by means of which the
toe or tip is closed, in order to produce sock.
[0003] This finishing operation is notoriously considered to be very important by sock manufacturers,
since it largely determines the quality of the finished product.
[0004] The tips of socks can be closed by linking or by means of mechanical sewing termed
"blind" sewing.
[0005] The linking operation is performed on appropriate machines and requires the manual
placement of each individual loop, at the opening of the tip, on appropriate pins
of the machine which are then affected by an extremely precise sewing so as to mutually
join the various loops.
[0006] Blind mechanical sewing is much easier and rapid to perform, since it does not require
the placement of each individual loop of the open tip of the sock but a less precise
positioning of the sock, which is then subjected to one or more sewing operations.
[0007] The best-finished and most desirable socks are obtained by linking, especially due
to the better finishing in the sewing region, which is scarcely detectable to the
touch and, when the sock is worn, produces no unpleasant feelings, but is also advantageous
from an aesthetic point of view since it has its own perfection of opposite threads
sewn together in a harmonious and symmetrical manner, so much that linking can be
visually recognized even apart from the tactile effect.
[0008] Linking naturally entails a considerable use of specialized labor which unavoidably
raises the retail cost of a pair of socks finished in this manner to high levels.
[0009] Therefore, machines for blind mechanical sewing, which do not require loop-by-loop
positioning and have been recently improved in their operating speed and in the durability
of the sewing they perform, i.e. in the "hold" of the stitches, are used extensively.
[0010] With machines of this type, an operator, even an unspecialized one, can finish up
to 2500 pairs of socks per day, whereas with linking a very expert operator might
achieve at the most the result of 300 pairs per day. The difference in terms of costs
is therefore significant.
[0011] On the other hand, the improvements in currently used machines which perform blind
sewing have only marginally affected the quality of the sewing in terms of aesthetic
quality and actual comfort for the user, since said sewing is in any case not only
immediately recognizable as blind-sewn and not linked but also necessarily causes
a certain unpleasant feeling of discomfort to the person who wears socks finished
in this way.
[0012] It should be noted that the most modern circular knitting machines for manufacturing
socks can be preset for preparing the tip of socks in a different manner depending
on whether linking or mechanical blind sewing is intended to be used.
[0013] In the case of linking, the open tip is ended with a raw of knitting with longer
loops with respect to the preceding row. Such row may be reinforced and is followed
by a knitted trim which has a density substantially equal to that of the previously
formed tip and is used exclusively for guiding during linking and is cut once linking
is completed.
[0014] If blind mechanical sewing is intended, the open tip is ended with a portion of knitting
generally constituted by 4-5 rows, for a total length of 5 mm, of a polyamide thread
which has a certain elasticity (such as for example helanca or Lycra) with tight knitting,
followed by a knitted trim as in the preceding case.
[0015] The presettings recommended by the companies which manufacture circular knitting
machines for hosiery and machines which perform blind sewing have always been of the
above described type, and it has never been possible to achieve a significant improvement
in the type of sewing obtained with a blind sewing machine; the sewing produced thereby
is very thick, hardly ever perfectly straight and aesthetically unpleasant.
[0016] According to what has been explained above, it would therefore be desirable to obtain,
by means of blind sewing, finished socks which have characteristics similar to those
of linked socks.
[0017] The aim of the present invention is to solve the above described problem by providing
a process which allows to manufacture an open-tip sock which can be finished by mechanical
blind sewing, whereby to obtain a finished sock which has, both aesthetically and
to the touch, characteristics which are similar to those of socks finished by linking.
[0018] Within the scope of this aim, an object of the invention is to provide a process
which is simple to carry out on both rectilinear and circular knitting machines.
[0019] Another object of the invention is to provide a process which allows extremely precise
blind sewing during finishing.
[0020] Further characteristics and advantages of the invention will become apparent from
the description of a preferred but not exclusive embodiment of the process according
to the invention, illustrated only by way of non-limitative example in the accompanying
drawings, wherein:
figure 1 is a view of the tip or toe region of a sock prepared for linking with a
known process;
figure 2 is a view of the tip region of a sock prepared for blind sewing with a known
process; and
figure 3 is a view of the tip region of a sock prepared with the process according
to the present invention.
[0021] With reference to figure 1, in order to conventionally knit a sock 1 which is to
be finished by blind sewing, after the steps of forming the leg, the heel, the foot
2 and the tip 3, a first portion of knitting 4, constituted by a few rows for an overall
length of approximately 5 mm, is knitted with a thin and elastic thread, generally
made of polyamide fiber, and a second portion of knitting 5 is knitted thereafter
with a thicker thread.
[0022] The first portion of knitting 4, which is to be affected by the sewing for closing
the tip, therefore has a reduced thickness with respect to the thickness of the knitting
in the actual tip region and with respect to the thickness of the knitting in the
second portion of knitting 5. Said second portion of knitting 5 acts as guiding trim
during the positioning of the sock on the sewing machine and during the sewing operation,
but does not safely avoid the possibility of movements of the sewing point within
the first portion of knitting 4, with consequent deformations of the sewing line which
is very often non-rectilinear, with thickenings of said sewing.
[0023] With reference to figure 2, in order to conventionally knit a sock 1a to be finished
by linking, after the conventional steps of forming the leg, the heel, the foot 2a
and the tip 3a, a row of knitting 4a, formed by loops with increased length with respect
to the previously formed tip loops, is knitted, and a portion of knitting 5a with
a stitch density similar to that of the tip 3a is then knitted.
[0024] In order to perform the linking operation, each loop of the row of knitting 4a is
fitted manually on a pin of the pin-holder ring of a linking machine. The portion
of knitting 5a simplifies this operation.
[0025] With reference to figure 3, in order to knit a sock 10 with the process according
to the present invention, after forming the leg, the heel, the foot 11 and the tip
12 in a known manner, a row of knitting 13 with loops of increased length with respect
to the previously knitted rows of the tip 12 is knitted; then a first portion of knitting
14, constituted by a few rows of knitting formed with a thinner thread with respect
to the thread used for the row 13, is knitted, and a second portion of knitting 15
is finally knitted using a thicker thread with respect to the thread used to knit
the first portion of knitting 14.
[0026] Conveniently, the row 13 is knitted with the addition of a reinforcement thread by
feeding the needles of the machine with two threads simultaneously in a per se known
manner.
[0027] The first portion of knitting 14 is preferably knitted with a helanca or Lycra polyamide
thread so as to obtain a portion of knitting which has a reduced thickness and a certain
elasticity. Said portion of knitting 14 is expediently constituted by approximately
six rows of knitting.
[0028] Finally, the second portion of knitting 15 has an overall length of approximately
1 cm and is preferably knitted using a low-cost thread, since it is to be eliminated
after finishing.
[0029] The process according to the invention can be easily performed on a known circular
machine simply by setting said machine so that, after knitting the actual tip, it
knits a row of knitting 13 with reduced stitch density, i.e. with longer loops. While
this row of knitting is being knitted, an additional thread guide is activated simultaneously
and feeds the reinforcement thread to the needles. These operations are easy to perform
by modifying the actuation program of modern circular knitting machines.
[0030] In order to knit the first portion of knitting 14 and the second portion of knitting
15, the machine is actuated as during the known preparation of the sock for mechanical
blind sewing, described with reference to figure 1.
[0031] It should be noted that in the tip of the sock prepared with the process according
to the invention, the first portion of knitting 14, besides having a certain elasticity,
has a reduced thickness with respect to the row of knitting 13 and to the second portion
of knitting 15. Due to this fact, the first portion of knitting 14 can be rapidly
and precisely positioned on the grip elements, generally clamps, with which blind
sewing machines are provided. In practice, the jaws of a clamp engage the first portion
of knitting 14 and the sock remains arranged correctly during sewing with no possibility
of accidental movements, since the row 13 and the second portion of knitting 15 act
as opposite shoulders by resting against the closed jaws of the clamp.
[0032] In an example of an embodiment which has actually been carried out, the process according
to the invention has been performed on a Lonati Goal model 362 single-cylinder circular
knitting machine preset for blind mechanical sewing preparation. By acting on the
actuation controls of the machine, in the manner known to any person skilled in the
art, the stitch density is changed at the end of the forming of the actual tip so
as to knit a row of knitting with reduced density with respect to the stitch density
used in forming the actual tip, and an additional thread guide is simultaneously moved
to knit so as to obtain a row of knitting with longer loops reinforced by the addition
of a thread.
[0033] The thread guides which fed the thread for forming the sock are then excluded from
knitting, and thread guides which feed a helanca or Lycra thread are moved to knit
so as to form consecutive rows of knitting, e.g., six rows.
[0034] A further exchange of the thread guides is subsequently performed so as to exclude
from the knitting the thread guides which bear the helanca or Lycra thread and move
back into knitting the thread of guides bearing the same thread used to form the sock
or a less valuable thread so as to form the second portion of knitting 15 for an overall
length of approximately 1 cm of said portion. The sock thus prepared is inserted on
a conventional sewing machine which performs blind sewing, and sewing with two passes
in line is performed; the first sewing is performed with two 20/2 helanca threads
at 28 stitches per 2.54 cm (28 stitches per inch), whereas the second sewing occurs
with an 80/2 cotton thread and a 20/2 helanca thread at 20 stitches per 2.54 cm (20
stitches per inch).
[0035] The result obtained was a perfectly rectilinear sewing with a thickness not perceivable
to the touch, and with a considerable aesthetic effect due to the tidiness and uniformity
of the stitches. Some experts to whom the sock thus finished was shown detected no
differences with respect to finishing performed by linking. It should be noted that
though the second sewing step with a cotton thread is not necessary, it provides a
particular aesthetic effect which is suitable for giving the item the appearance of
a true linking.
[0036] In practice it has been observed that the process according to the invention fully
achieves the intended aim, since it allows to obtain open-tip socks which can be subjected
to finishing by means of blind mechanical sewing, and therefore with reduced manufacturing
costs, while obtaining a product which is qualitatively comparable with socks finished
by linking.
[0037] The process thus conceived, as well as the semiworked item obtain thereby, are susceptible
to numerous modifications and variations, all of which are within the scope of the
inventive concept; all the details may furthermore be replaced with technically equivalent
elements.
[0038] In practice, the materials employed, so long as compatible with the specific use,
as well as the dimensions, may be any according to the requirements and the state
of the art.
[0039] Where technical features mentioned in any claim are followed by reference signs,
those reference signs have been included for the sole purpose of increasing the intelligibility
of the claims and accordingly, such reference signs do not have any limiting effect
on the scope of each element identified by way of example by such reference signs.
1. Improved process for manufacturing socks on hosiery machines, comprising a leg forming
step, a heel forming step, a foot forming step and a tip forming step, characterized
in that said tip forming step is completed by knitting: a row of knitting with increased
loop length with respect to the already knitted tip rows, a first portion of knitting
constituted by a plurality of rows of knitting knitted with a thinner thread with
respect to the thread used for knitting said first row, and subsequently a second
portion of knitting constituted by a plurality of rows of knitting, knitted with a
thicker thread with respect to the thread used for knitting said first portion of
knitting.
2. Process according to claim 1, characterized in that a reinforcement thread is added
while knitting said row of knitting with increased loop length.
3. Process according to claim 1, characterized in that said first portion of knitting
is knitted with a polyamide thread.
4. Process according to claim 3, characterized in that said polyamide thread is made
of helanca.
5. Process according to claim 3, characterized in that said polyamide thread is made
of Lycra.
6. Process according to one or more of the preceding claims, characterized in that said
second portion of knitting is at least 1 cm long.
7. Process according to claim 1, characterized in that said second portion of knitting
is knitted with a less valuable thread with respect to the thread used to knit the
sock.
8. Process according to claim 1, characterized in that said first portion of knitting
is constituted by approximately six rows of knitting.
9. Process according to claim 1, characterized in that it is performed with a circular
machine.
10. Semiworked knitted item for manufacturing socks, characterized in that it comprises,
at the tip of the sock which is manufactured so that it is open and is intended to
be closed by sewing, a final knitting which is composed, starting from the body of
the sock, of a row of knitting with increased loop length with respect to the preceding
rows, a first subsequent portion of knitting constituted by a plurality of rows of
knitting knitted with a thinner thread with respect to the thread used for said first
row, and of a second portion of knitting constituted by a plurality of rows of knitting
knitted with a thicker thread with respect to the thread used for said first portion
of knitting.
11. Item according to claim 10, characterized in that said row of knitting with increased
loop length comprises an additional reinforcement thread.
12. Item according to claim 10, characterized in that said first portion of knitting is
made of polyamide thread.
13. Item according to claim 12, characterized in that said polyamide thread is constituted
by a helanca thread.
14. Item according to claim 12, characterized in that said polyamide thread is constituted
by a Lycra thread.
15. Item according to claim 10, characterized in that said second portion of knitting
has a length of approximately 1 cm.
16. Item according to claim 10, characterized in that said second portion of knitting
is knitted with a less valuable thread with respect to the thread used to knit the
sock body.
17. Item according to claim 10, characterized in that said first portion of knitting is
constituted by approximately six rows of knitting.