U.S. patent application number 10/471186 was filed with the patent office on 2004-08-12 for device for picking up a tubular knitted article from a knitting machine and for sewing the toe.
Invention is credited to Conti, Paolo.
Application Number | 20040154341 10/471186 |
Document ID | / |
Family ID | 11442097 |
Filed Date | 2004-08-12 |
United States Patent
Application |
20040154341 |
Kind Code |
A1 |
Conti, Paolo |
August 12, 2004 |
Device for picking up a tubular knitted article from a knitting
machine and for sewing the toe
Abstract
Described herein is a device for picking up a tubular knitted
article (M) from a cylinder (5) of a circular knitting machine (3)
and for closing the toe of said article. The device comprises a
sewing machine for sewing the toe of the tubular article and a
suction pipe (13) which develops from an intake end (13A), in an
area where the tubular article is picked up from the circular
knitting machine, to an output end (13B), in an area where the toe
of the article is sewn. Also provided is a guide element (15) for
guiding the tubular article, said guide element developing inside
said suction pipe and extending inside the cylinder of the circular
knitting machine. Between the guide element (15) and the inner wall
of the suction pipe (13) there remains a space for transit of the
tubular article.
Inventors: |
Conti, Paolo; (Firenze,
IT) |
Correspondence
Address: |
MCGLEW & TUTTLE, PC
1 SCARBOROUGH STATION PLAZA
SCARBOROUGH
NY
10510-0827
US
|
Family ID: |
11442097 |
Appl. No.: |
10/471186 |
Filed: |
February 23, 2004 |
PCT Filed: |
March 4, 2002 |
PCT NO: |
PCT/IT02/00129 |
Current U.S.
Class: |
66/149S |
Current CPC
Class: |
D05B 23/009 20130101;
D04B 9/40 20130101; D04B 15/92 20130101; D06G 3/02 20130101; D05B
23/007 20130101 |
Class at
Publication: |
066/149.00S |
International
Class: |
D04B 035/00; D04B
027/34; D04B 015/88 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 8, 2001 |
IT |
FI2001A000038 |
Claims
1. A device for picking up a tubular knitted article from a
cylinder of a circular knitting machine and for closing the toe of
said article, said device comprising means for closing said toe of
the tubular article and being characterized in that it comprises: a
suction pipe that develops from an intake end, in an area where the
tubular article is picked up from the circular knitting machine, to
an output end, in an area where the toe of the article is sewn; and
a guide element for guiding the tubular article, which develops
inside said suction pipe and extends outside the latter from the
intake-end side to be inserted inside the cylinder of said circular
knitting machine, there being provided, between the guide element
and the inner wall of the suction pipe, a space for transit of the
tubular article.
2. The device according to claim 1, in which to the output end of
the suction pipe there is associated a system for extraction of the
tubular article from the suction pipe and for turning said tubular
article inside out onto the outside of the suction pipe.
3. The device according to claim 1, or claim 2, in which said
suction pipe is internally divided into two consecutive portions by
an openable intermediate separator.
4. The device according to claim 1, or 2, or 3, in which associated
to said suction pipe are means for supporting the guide element
inside the suction pipe, said supporting element enabling transit
of the tubular article in the space between the inner wall of the
suction pipe and the guide element inside it.
5. The device according to claim 4, in which said supporting means
comprise transverse sliders which are carried by the suction pipe
and are mobile for engaging the guide element inside said suction
pipe and for alternately being released from the latter.
6. The device according to claim 4 or 5, in which said supporting
means are set in three sections set at a distance apart along the
suction pipe.
7. The device according to claims 3 and 6, in which two of said
sections are set in the portion of the suction pipe between the
intake end and the intermediate separator, and one of said sections
is set between the output end and the intermediate separator.
8. The device according to one or more of the foregoing claims, in
which said guide element has a portion which is extensible towards
the output end of the suction pipe.
9. The device according to claim 8, in which said extensible
portion is provided with single-acting pneumatically controlled
telescopic elongation means.
10. The device according to claims 3 and 9, in which said
intermediate separator is associated to an air-feed channel for
controlling telescopic elongation of said guide element.
11. The device according to one or more of the foregoing claims, in
which said guide element is made up of two parts which are hinged
together about an axis orthogonal to the axis of the suction
pipe.
12. The device according to at least claim 2, in which said system
for extraction of the tubular article from the suction pipe
comprises: widening members for widening the tubular article at the
initial edge of the article itself, said members causing widening
of the initial edge of the tubular article beyond the outer
diameter of the suction pipe; and members for turning the tubular
article inside out from inside the suction pipe onto the outside of
the latter.
13. The device according to at least claim 12, in which said
widening members comprise a plurality of stems which are
approximately parallel to the axis of the suction pipe and are
provided with a motion of approach to and recession from the axis
of the suction pipe so as to assume a position close to the axis of
the suction pipe and a position external to the diameter of the
suction pipe, said stems being axially mobile along the outside of
the suction pipe.
14. The device according to claim 13, in which said stems are each
carried by a plate roughly orthogonal to the axis of the suction
pipe; when the stems are in the position close to the axis of the
suction pipe, the plates forming a contrast wall for arrest of the
tubular article that is being conveyed inside said suction
pipe.
15. The device according to claim 14, in which each of said plates
is carried by a rotating spindle roughly parallel to the axis of
the suction pipe and to said stems, the rotation of said spindle
causing the approach and recession movement of the stems with
respect to the axis of said suction pipe.
16. The device according to claim 14 or claim 15, in which the
contrast wall formed by said plates when the stems are in a
position close to the axis of the suction pipe has a central hole
aligned to the guide element, said guide element inserting, with
its own end, inside said hole.
17. The device according to one or more of claims 12 to 16, in
which said guide element has a lateral seat for insertion of said
stems.
18. The device according to one or more of claims 12 to 17, in
which said members for turning the tubular article inside out
comprise radial pushers that move radially and axially with respect
to said suction pipe and outside the latter so as to press against
the outer surface of the suction pipe and draw along said outer
surface the tubular article.
19. The device according to one or more of claims 12 to 18, in
which associated to said widening members is a suction line for
sucking the tubular article up against said widening members.
20. The device according to one or more of claims 12 to 19, in
which said widening members and said members for turning the
tubular article inside out are carried by a unit which is axially
mobile along the suction pipe.
21. The device according to claims 19 and 20, in which said suction
line is connected to a suction chamber formed in said unit.
22. The device according to one or more of the foregoing claims, in
which said suction pipe comprises an end part which is angularly
mobile about its own axis with respect to the remaining part of the
suction pipe, an actuator being provided for controlling the
movement of rotation of said end part about its own axis.
23. The device according to one or more of the foregoing claims, in
which at its own output end the suction pipe has slits for passage
of a member for gripping the end edge of the article.
24. The device according to claim 23, in which said gripping member
has two brackets which can be brought up to and moved away from one
another so as to engage the tubular article at the end edge of the
latter in two roughly diametrally opposite points and to tension
said end edge, said brackets being axially mobile with respect to
said suction pipe.
25. The device according to one or more of the foregoing claims,
comprising a member for retention of the tubular article after
sewing of the toe, in order to carry out cutting of the part of
fabric external to the seam thus formed.
26. The device according to at least claim 3, in which associated
to said suction pipe is a first suction opening, set between the
intermediate separator and the intake end of said suction pipe, and
a second suction opening, set between the output end and the
intermediate separator, through said second suction opening the
article being removed after sewing of the toe thereof.
27. The device according to at least claim 3, in which said
intermediate separator is made up of a pair of jaws which engage
said guide element inside the suction pipe.
28. The device according to at least claim 8, in which said
extensible portion is engaged, at its own free end, to a system for
closing the output end of the suction pipe.
29. The device according to claims 14 and 28, in which said closing
system consists of said plates that carry said stems, said plates
in their closed configuration defining a hole for engagement of the
free end of said extensible portion.
Description
TECHNICAL FIELD
[0001] The present invention relates to a device for picking up a
knitted article, such as a sock, stocking or the like, from the
circular knitting machine that has formed it and for closing the
toe of said article with a sewing operation.
STATE OF THE ART
[0002] Many tubular knitted articles, such as socks and stockings,
are currently produced on circular knitting machines, namely
knitting machines equipped with a cylinder with a circular bed of
needles. The article that is obtained has the shape of a tube with
an initial edge and an end edge. The latter must be closed, by
sewing two opposed flaps, to form the toe of the article. For this
purpose, according to the most traditional technique, the tubular
article, which is still open, is unloaded from the circular machine
that has formed it and is sent on to a different manufacturing
department where it is taken up again and it is sewn or undergoes
linking.
[0003] In order to simplify the manufacturing process, cut down on
labour and in general on production costs, systems and devices have
recently been studied that enable sewing of the toe to be obtained
in a simpler way, which can easily be automated and in certain
cases may be carried out directly on the circular knitting machine
that produces the article.
[0004] EP-A-0 592 376 and EP-A-0 635 593 describe circular knitting
machines and corresponding knitting methods in which the tubular
article is closed at the end of the knitting operation. These
machines and methods present the drawback of requiring a particular
construction of the machine, with machine accessories and parts
that are not normally available and that cannot be inserted into
traditional and pre-existing knitting machines.
[0005] EP-A-0 679 746 describes a device for picking up a tubular
article from a circular knitting machine in order to carry out
subsequent sewing of the toe off the circular machine. The device
is complex, in particular as regards the means for picking up and
handling the article.
[0006] WO-A-00/01869 describes a device and method for picking up a
tubular article from the circular machine that produces it and for
closing the toe of the article by sewing. The device described in
the above document is particularly advantageous in so far it has a
simple, reliable and inexpensive structure. In addition, the method
that may be implemented with this known device is fast and
consequently enables high production rates to be achieved. However,
also this device presents a number of drawbacks deriving from the
fact that it must be inserted into the needle cylinder of the
circular machine, and consequently in certain cases it requires
adaptation of the circular machine, with an increase in the
diameter of the needle cylinder. In addition, a sewing machine must
be provided underneath the circular knitting machine.
OBJECTS AND SUMMARY OF THE INVENTION
[0007] An object of the present invention is to provide a device of
the type specified above that will enable simple and reliable
handling of the tubular article and that can be advantageously
designed in such a way that it can be applied to existing circular
machines without said machines having to be modified.
[0008] The above and further purposes and advantages, which will
clearly appear to persons skilled in the art from the ensuing text,
are achieved thanks to a device characterized by a suction pipe
that develops from an intake end, in an area where the tubular
article is picked up from the circular knitting machine, to an
output end, which is located in an area where the toe of the
article is sewn, and by an element for guiding the tubular article,
which develops inside said suction pipe and extends outside it from
the intake end so as to be inserted inside the cylinder of said
circular knitting machine, there being provided, between the guide
element and the inner wall of the suction pipe, a space for transit
of the tubular article.
[0009] With the above arrangement, the tubular article is formed by
the circular bed of needles around the guide element, which may be
made even with a relatively modest cross section and hence may be
inserted into a needle cylinder of the size currently used in
knitting machines for the production of hosiery articles. The
tubular article that has been formed is sucked inside the duct and
is guided along the latter by the guide element until it reaches
the output end of the suction pipe, to which a system is associated
for extraction of the tubular article from the suction pipe and for
turning the article inside out onto the outside of the suction
pipe.
[0010] According to a particularly advantageous embodiment of the
invention, the suction pipe is internally divided into two
consecutive portions by an openable intermediate separator. The
latter also has the function of supporting the guide element. When
the intermediate separator is opened to enable passage of the
tubular article, the guide element is temporarily supported by
appropriate supporting means that can move in such a way as to
enable passage of the tubular article inside the space between the
inner surface of the suction pipe and the guide element.
[0011] According to a particularly advantageous embodiment of the
invention, the guide element may have a telescopically extensible
portion which can extend towards the output end of the suction
pipe. Said telescopically extensible portion is extended as far as
the output end of the suction pipe when the tubular article is to
reach the sewing means associated to the output end, and is then
retracted to facilitate discharge of the tubular article after
closing of the toe. In this case, discharge may, take place by
suction in the reverse direction inside the suction pipe.
[0012] In order to facilitate discharge of the tubular article, it
is possible to envisage that the guide element should be made up of
two parts hinged together about an axis orthogonal to the axis of
the suction pipe, in such a way that the guide element will be able
to come up to the inner wall of the suction pipe to enable passage
of the tubular article that has been sewn.
[0013] According to an embodiment of the invention, the system for
extracting the tubular article from the suction pipe may
comprise:
[0014] widening members for widening the tubular article at the
initial edge of the article itself, said widening members causing
widening of the initial edge of the tubular article beyond the
outer diameter of the suction pipe; and
[0015] members for turning the tubular article inside out, from the
inside of the suction pipe to the outside.
[0016] The widening members may comprise a plurality of stems which
are roughly parallel to the axis of the suction pipe and are
provided with a motion of approach to and recession from the axis
of the suction pipe so as to assume a position close to the axis of
the suction pipe and a position outside the diameter of the suction
pipe, said stems being axially mobile along the outside of the
suction pipe.
[0017] It is also possible to envisage that the stems should be
carried each by a plate roughly orthogonal to the axis of the
suction pipe. In this way, when the stems are in the position close
to the axis of the suction pipe, the plates form a contrast wall
for arrest of the tubular article that is being conveyed inside
said suction pipe. This renders the configuration of the device
particularly, simple, even though the possibility is not ruled out
of separating the stems from the plates and controlling the latter
separately from and independently of the stems.
[0018] The members for turning the article inside out may comprise,
for example, radial pushers that are mobile radially and axially
with respect to said suction pipe and outside the latter to press
the tubular article against the outer surface of the suction pipe
and draw it along said outer surface.
[0019] The invention also relates to a circular knitting machine
comprising a device of the type described above.
[0020] Further advantageous characteristics of the device according
to the invention are specified in the attached claims and will be
described in greater detail hereinafter with reference to a
non-limiting example of embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] A better understanding of the present invention will be
provided by the ensuing description and by the attached drawings,
which illustrate a non-limiting example of embodiment of the
invention. In greater detail, in the drawings:
[0022] FIG. 1 is a perspective view of a device for picking up a
tubular knitted article from a cylinder of a circular knitting
machine and of a device for sewing the toe of the article;
[0023] FIG. 2 is a side view according to the line II-II of FIG.
1;
[0024] FIG. 3 is a view according to the line III-III of FIG.
2;
[0025] FIG. 4 is a perspective view of the devices combined with a
circular knitting machine;
[0026] FIG. 5 is a perspective view of one part of the sewing area,
with elements removed for reasons of greater clarity of the
drawing;
[0027] FIG. 6 is similar to FIG. 5 and shows the same members from
a different observation point;
[0028] FIG. 7 is a perspective view of the sewing machine for
closing the toes of tubular articles picked up by the pick-up
device;
[0029] FIG. 8 is a perspective view of an intermediate separator
set along a suction pipe of the pick-up device;
[0030] FIG. 9 shows the internal members of the intermediate
separator of FIG. 8;
[0031] FIG. 10 is a longitudinal cross-sectional view of the
intermediate separator;
[0032] FIG. 11 shows a mobile axial unit that carries the widening
members and the members for turning the tubular article inside out
for preparing it for sewing of the toe;
[0033] FIG. 12 shows the same unit as FIG. 11 with parts
removed;
[0034] FIG. 13 is a longitudinal cross-sectional view of the unit
of FIGS. 11 and 12;
[0035] FIG. 14 is a view from below according to the line XIV-XIV
of FIG. 13;
[0036] FIG. 15 shows a pair of bars for retention of the article
during the initial steps of sewing of the toe;
[0037] FIG. 16 shows a comb-like structure for engagement of the
article during sewing and a cutting member housed inside the
comb-like structure;
[0038] FIGS. 17 to 28 show, in a cross-sectional plane passing
through the axis of the suction pipe, the device for picking up the
article (or part of the device), as well as the widening members
and the members for turning the article inside out in order to
prepare it for sewing of the toe, FIG. 17A being an enlargement of
the output area of the suction pipe;
[0039] FIG. 29 is a cross-sectional view according to the line
XXIX-XXIX of FIG. 28;
[0040] FIG. 29A is an enlargement of the central area of FIG.
29;
[0041] FIGS. 30 to 32 are cross-sectional views, according to the
line XXX-XXX of FIG. 29, of the pair of bars for retention of the
article and of the comb-like structure in the step of engagement of
the article and insertion of the comb-like structure into the
respective row of stitches, as a preliminary step to sewing of the
toe;
[0042] FIG. 33 shows the sewing machine and the comb-like structure
inserted in the article during sewing;
[0043] FIG. 34 is an enlargement of a detail of FIG. 33;
[0044] FIG. 35 is a schematic illustration of the action of the
needle of the sewing machine during the sewing operation;
[0045] FIGS. 36 to 39 show the steps for cutting the loops of the
row of the tubular article inside which the comb-like structure has
been inserted;
[0046] FIG. 40 shows the step of removal of the residue of yarn
after cutting of the loops adjacent to the sewing row;
[0047] FIG. 41 illustrates a detail of FIG. 40;
[0048] FIG. 42 is a perspective view illustrating a possible
embodiment of the system for removal of the residue of yarn;
and
[0049] FIG. 43 is an axial sectional view of the end portion of the
suction pipe in the step of removal of the tubular article after
the sewing operation;
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE
INVENTION
[0050] The devices for picking up and sewing tubular articles are
shown in FIG. 4 in combination with a circular knitting machine,
and in isolation from the knitting machine in FIGS. 1 to 3. The
internal structure of the pick-up device may be seen in FIGS. 17 to
28. In some of the figures, parts of the devices have been removed
for greater clarity of representation. In what follows generic
reference will frequently be made to the ensemble made up of the
pick-up device and sewing device as to a single device for picking
up the article and closing the toe, it being, however, understood
that the pick-up device may be combined with a different device for
closing the toe and vice versa.
[0051] In the attached drawings, the device for picking up the
tubular article and closing the toe is designated, as a whole, by
1, whilst 3 designates, as a whole, the circular knitting machine
that produces the tubular article. Of the circular knitting machine
3, only the essential components are indicated, which may be seen
in particular in FIGS. 17 to 19, which show the cylinder 5 of the
needles 7 that form a circular needle bed, in a way in itself
known. The needle cylinder 5 is supported, in such a way that it
can turn about its own axis, by means of a support, designated by
9, and is set in rotation by means of members (not illustrated)
which mesh with a crown gear 11. The members for controlling the
needles 7 of the circular bed are not shown, but are in themselves
known, as are also all the other members of the circular knitting
machine 3, which consequently will not be described in any further
detail herein.
[0052] The device 1 comprises a suction pipe 13, which is
substantially U-shaped, and one end of which, designated by 13A,
will hereinafter be referred to as intake end, whilst one end,
designated by 13B, will hereinafter be referred to as output end.
The intake end 13A is set underneath the cylinder 5 of the needles
7 of the knitting machine 3. In this way, the suction pipe 13 may
have any diameter whatsoever, which is independent of the, internal
diameter of the cylinder 5.
[0053] Inside the suction pipe 13 there develops a guide element,
designated as a whole by 15. Said guide element 15 (which in the
example illustrated has a substantially tubular conformation with a
circular cross section) extends outside the suction pipe 13 from
the intake end 13A as far as inside the cylinder 5 of the needles 7
of the knitting machine 3. The top end of the guide element 15
approximately reaches the plane of formation of the knitted fabric
of the knitting machine 3.
[0054] The guide element 15 is made up of two parts, one of which
is designated by 15A and the other by 15B. These two parts are
hinged about an axis of trace 17 (see in particular FIG. 17)
orthogonal to the axis (namely, to the median line) of the suction
pipe 13 and of the guide element 15 itself. The reason for this
configuration will appear more clearly from the ensuing description
of the operation of discharge of the article with the toe
closed.
[0055] The guide element 15 is supported, inside the suction pipe
13, by means of an intermediate separator, which is designated as a
whole by 19, and the parts of which are illustrated in detail in
FIGS. 8 to 10. The intermediate separator 19 also performs the
function of dividing the suction pipe 13 into two consecutive
parts, the first of which develops between the intake end 13A and
the intermediate separator 19, and the second between the latter
and the output end 13B.
[0056] As may be seen in detail in FIGS. 8 to 10, the intermediate
separator 19 is made up of a pair of jaws 21 and 22 operated by
respective actuators 23 and, 24, which, in the example illustrated,
consist of cylinder-piston systems. The jaws 21 and 22 are fixed to
the stems of the cylinder-piston actuators 23 and 24 and have
V-shaped front profiles, designated by 21V and 22V. The jaw 21 has
a slot, inside which the front portion of the jaw 22 penetrates in
such a way as to grip, between the two profiles 21V and 22V, the
guide element 15, withholding it in a coaxial position, namely
centred with respect to the suction pipe 13.
[0057] The jaws 21 and 22 slide in a guide frame 25 which is fixed
to the suction pipe 13.
[0058] As may be seen in FIGS. 9 and 10 (in the latter figure the
jaws 21 and 22 being shown in the closed condition), the jaw 22 has
an internal duct, designated by 27, which opens onto the profile
22V and onto the top portion of the jaw itself (see in particular
FIG. 9). The frame 25 has a slotted opening 29 in a position
corresponding to the outlet area of the internal duct 27 to enable
application of a flexible pipe or hose that connects the internal
duct 27 to a source of air under pressure (not shown) for the
purposes that will be clarified in what follows.
[0059] As may be seen in particular in FIGS. 17, 18 and 19, the
guide element 15 has (in its part 15B) a hollow structure inside
which a stem 15C is housed that terminates with a head 15E (see in
particular FIG. 17A), said stem constituting a telescopically
extensible portion of the guide element itself. The reference
number 15D designates a extension spring that forces the stem 15C
to return into the hollow tubular part of the guide element. The
air under pressure, which can be supplied through the internal duct
27 of the jaw 22, has the function of pressurizing the internal
area of the hollow part 15B of the guide element 15 to overcome the
force of the extension spring 15D and to extract the stem 15C until
it reaches the position illustrated in FIGS. 17 to 19, whilst in
FIG. 20 the stem 15C is shown in a retracted position inside the
hollow part of the guide element 15.
[0060] Since the jaws 21 and 22 of the intermediate separator 19
can open, thus releasing the guide element 15 in order to enable
passage of the tubular article which must pass along the suction
pipe 13 (as will be clarified in what follows), along the suction
pipe 13 there are provided further systems for temporary support of
the guide element 15 inside the suction pipe 13. These supporting
means are clearly visible in FIGS. 1, 2 and 3 and are represented
in a simplified way in the remaining figures. They are made up of
three sets of sliders 31, 32, 33 positioned in respective three
sections set at distances apart along the development of the
suction pipe 13. In greater detail, two sets of three sliders,
namely the sets of three sliders 31 and 32, are positioned on
planes orthogonal to the axis of the suction pipe between the
intake end 13A of the suction pipe and the intermediate separator
19. The last set of sliders 33 is positioned on a plane between the
intermediate separator 19 and the output end 13B of the suction
pipe 13. The sets of sliders 31, 32 and 33 can be brought back or
retracted in such a way that they do not project inside the suction
pipe 13, so as to leave completely free the space between the inner
wall of the suction pipe 13 and the guide element is.
Alternatively, the sliders of each set can be displaced radially
inwards in such a way that they engage the guide element 15,
supporting it inside the suction pipe 13. Synchronized actuation of
the sets of sliders 31, 32, 33 enables (in the way that will be
clarified hereinafter) transit of the tubular article discharged
from the circular needle bed 37 along the suction pipe 13 towards
the output end 13B of the latter.
[0061] The suction pipe 13 has an end part 13C which is angularly
mobile about its own axis with respect to the remaining part of the
suction pipe. The movement of rotation of the end part 13C of the
suction pipe 13 is imparted by an actuator 35, for example a
stepper motor. The latter enables adjustment of the angular
position of the part 13C of the suction pipe 13 with respect to the
remaining part (which is fixed on the supporting structure) of the
pipe, in order to orient appropriately the tubular article before
sewing of the toe of the latter, as will emerge clearly from the
detailed description of the modes of operation of the entire
device.
[0062] At the output end 13B of the suction pipe 13 there is
provided a sewing area, designated as a whole by 37. Located in
this area are the members that have the function of extracting the
tubular article, turning it inside out, from inside the suction
pipe 13, of closing the toe of said article by sewing and
re-inserting the article into the suction pipe 13 so as to
discharge it finally from the device.
[0063] Set in the sewing area 37 is a unit 39 which surrounds the
suction pipe 13, and more precisely the portion 13C of the latter.
The unit 39 carries, in a way that will be described in detail with
reference to FIGS. 11 to 14, the widening members and the members
for turning the tubular article inside out before it is sewn. The
unit 39 is axially mobile, in the direction indicated by the arrow
f39, along the end part 13C of the suction pipe 13. For this
purpose, there are provided a slide guide 41 and an actuator 43
which controls movement of the unit 39.
[0064] The unit 39 is illustrated in detail in a perspective view
in FIGS. 11 and 12, in a cross-sectional view in FIG. 13, and in a
view from below in FIG. 14. FIG. 11 shows a ring 45 which forms
part of the unit 39 and which is coaxial with the axis of the part
13C of the suction pipe 13. The ring 45 supports a plurality of
radial pushers 47 constituting the members for turning the tubular
article inside out before sewing of the toe. Each pusher 47 is
provided with a radial movement controlled by a corresponding
actuator 49, for example a small cylinder-piston actuator. Beneath
the ring 45, the unit 39 has a wall 51 which delimits an internal
suction chamber 53. The latter is connected, through an opening 55,
to a suction line, the connection of which to the suction chamber
53 is designated by 57.
[0065] Set inside the suction chamber 53 present in the unit 39 are
five shaped plates 59 supported by rotating spindles 61. Each
shaped plate 59 carries, in a position at a distance from the
corresponding supporting spindle 61, a stem 63 parallel to the
spindle 61 itself. The conformation of the shaped plates 59 is such
that (see in particular FIG. 12, in which the overlying pushers 47,
their actuators 49 and the ring 45 have been removed for clarity of
representation), in a first angular position of the spindles 61,
they form a substantially continuous wall orthogonal to the axis of
the suction pipe 13, or more exactly to the end part 13C of the
suction pipe 13. The wall formed by the shaped plates 59 has a
central hole 65 for the purposes that will be clarified
hereinafter.
[0066] The shaped plates 59 are controlled in such a way that they
open simultaneously by means of an oscillation of each spindle 61
about its own axis. For this purpose, a mechanism is provided,
which is shown in FIGS. 13 and 14 and which comprises pinions 67
fixed to the bottom end of each spindle 61 and meshing with an
internal-toothing crown gear 69, the rotation of which causes
spontaneous rotation of the pinions 67 and thus of the spindles 61.
Rotation of the toothed crown gear 69 is obtained by means of a
pinion 70 fitted on a shaft 72 which is driven in rotation about
its own axis by means of a cylinder-piston actuator 74.
[0067] Set above the unit 39, and approximately aligned with the
end part 13C of the suction pipe 13, is a gripping member,
designated as a whole by 71, for gripping the tubular article that
is to be sewn. The gripping member comprises a pair of brackets 73
(see in particular FIGS. 1 to 3 and 5 and 6) which are mobile with
respect to one another with a movement of approach and recession
represented by the double-headed arrow f73 (see in particular FIGS.
5 and 6). Movement in the direction indicated by the arrow f73 is
obtained by a pair of cylinder-piston actuators associated to the
brackets 73 and carried by a structure which is in turn provided
with movements according to a horizontal axis X and a vertical axis
Y (see again in particular FIGS. 5 and 6). As will emerge clearly
hereinafter, the brackets 73 can be brought up to one another for
penetrating inside the suction pipe 13 and gripping the end edge of
the tubular article, and then tensioning it and carrying it to the
sewing machine for the subsequent sewing operation.
[0068] The structure that carries the member 71 for gripping the
tubular article is supported by a base structure 75, which is in
turn constrained to a fixed frame, for example the frame itself of
the knitting machine 3. The base structure 75 carries a pair of
bars 77 and 79 which are roughly rectilinear. The bar 77 is fixed
to a portion of metal section 81 which is mobile, as indicated by
the double-headed arrow f81, by means of cylinder-piston actuators
(not shown). In this way, the bar 77 can move away from and up to
the bar 79, which is, instead, fixed with respect to the base plate
75.
[0069] Underneath the fixed rectilinear bar 79, a comb-like
structure 83 is provided, which is illustrated in isolation and in
detail in FIG. 16. The comb-like structure 83 has a plurality of
teeth 85 and is made up of two portions 83A and 83B, which are
connected together and define an intermediate seat for sliding of a
cutting blade 87. The comb-like structure 83 is mobile as indicated
by the double-headed arrow f83 (see in particular FIG. 6) in a
direction orthogonal to the longitudinal development of the fixed
rectilinear bar 79. The cutting blade 87 housed inside the
comb-like structure 83 moves together with the comb-like structure
83, following the movement of the latter as indicated by the arrow
f83. The movement is obtained by cylinder-piston actuators or
equivalent actuators, designated by 89 in FIG. 6.
[0070] As may be seen in particular in FIG. 16, the cutting blade
87 is provided with a plurality of slots 87A which are inclined
with respect to the cutting edge 87B of the blade 87. Into the
slots 87A there insert pins 83C which are fixed to the portion 83B
of the comb-like structure 83. At one of its ends, the blade 87
extends to form an appendage 87C in which a slot 87D orthogonal to
the cutting edge 87B of the blade itself is made. In said slot 87D
there engages a slider 91 provided with a movement, parallel to the
cutting edge 878, imparted by a cylinder-piston actuator or
equivalent actuator 93. The actuator 93 is carried by the base
plate 75, as may be seen in particular in FIG. 6. Thanks to the
slot 87D, the cutting blade 87 can move in a direction orthogonal
to the cutting edge 87B to follow the movement indicated by the
double-headed arrow f83 of the comb-like structure 83, all the time
maintaining mechanical connection with the actuator 93. Operation
of the actuator 93 causes a thrust in the direction indicated by
the arrow f87 (FIG. 16) on the blade 87, which consequently (thanks
to the arrangement of the pins 83C and of the inclined slots 87A)
will perform a movement with one component that is parallel and one
component that is orthogonal to the longitudinal development of the
comb-like structure 83. The function of this movement is, as will
be clarified in what follows, that of cutting the loops of the row
of stitches inside which the comb-like structure 83 is inserted for
carrying out sewing of the toe of the tubular article.
[0071] In the sewing area 37 there is moreover provided a sewing
machine, designated as a whole by 95, and illustrated in isolation
from the other mechanical members in FIG. 7. The sewing machine 95
has been omitted for reasons of clarity of representation in FIGS.
1, 2 and 3. The sewing machine has a sewing needle 96 and a mouth
for suction of the sewing thread 99. The reference number 101
designates the so-called "crochet", which imparts the raising and
lowering movement on the sewing thread for the latter, fed by the
thread bobbin, to be appropriately picked up by the sewing needle
96. The shape of the crochet 101 is provided purely by way of
example. The crochet may, for instance, also be of the rotating or
oscillating type. Likewise, the shape of the needle co-operating
with it may be different. The structure of the sewing machine 95 is
of a type in itself known to persons skilled in the art, and
consequently will not be described in greater detail herein. The
type of sewing performed by the needle 96 will in any case be
described in greater detail with reference to the operation of the
device.
[0072] The sewing machine 95 is provided with a sewing movement,
indicated by the arrow f95 in FIG. 4, imparted by an actuator,
designated as a whole by 97 again in FIG. 4.
[0073] Associated to the sewing machine 95 is a retention member
for withholding the tubular article after sewing of the toe in
order to carry out cutting of the part of fabric external to the
seam. The retention member is designated as a whole by 103, and its
position with respect to the other members of the device is
illustrated in FIG. 4, whilst its structure is illustrated in
detail in the perspective representation of FIG. 15.
[0074] The retention member 103 comprises a pair of bars 105, which
are substantially parallel to the movement of the sewing machine 95
and to the fixed bar 77 and mobile bar 79. The retention bars 105
are provided with a movement orthogonal to their own development in
the direction indicated by the double-headed arrow f105 in FIG. 15.
In this way, they can be brought up to one another for withholding
the article, or moved away from one another for releasing it. The
movement is imparted by cylinder-piston actuators (not shown)
housed in the structure of the retention member 103 fixed to the
sewing machine 95. Since the retention member 103 is fixed to the
sewing machine 95, it is also translated integrally with the sewing
machine when the latter performs the sewing movement in the
direction of the arrow f95. This enables the bars 105 to be brought
into alignment with the tubular article that is being sewn.
[0075] Finally, fixed to the sewing machine 95 is a system for
removal of the residue of yarn after the cutting operation has been
performed by the blade 87, said system being designated as a whole
by 107, and its position with respect to the other members of the
device being shown in FIG. 4. The structure of the removal system
107 in a possible embodiment is illustrated in the perspective
representation of FIG. 42. The removal system 107 is provided with
one or more brush members 109 which rotate about the axis of a
vertical shaft which is inserted into a suction mouth 111 through
which the residue of yarn separated from the tubular article by the
brush 109 is sucked in and removed.
[0076] Operation of the device so far described is illustrated in
what follows with particular reference to FIGS. 17 to 43.
[0077] FIG. 17 shows the end step of knitting of a tubular article
M by the needles 7 of the circular bed of needles of the circular
knitting machine 3. The tubular article is knitted starting from an
edge B1, which in FIG. 17 is in the bottom part and which in the
finished article will remain open. When the tubular article M is a
sock, said edge constitutes the elastic border of the sock. The
final knitting step envisages formation of an edge B2 which is
designed to be sewn to form the closed toe of the finished
product.
[0078] During formation, the tubular article M comes to set itself
in the space between the cylinder 5 of the needles 7 and the guide
element 15, and more precisely the part of said guide element that
projects with respect to the intake end 13A of the suction pipe 13.
In this step, the intermediate separator 19 set along the suction
pipe 13 is closed, and hence the jaws 21 and 22 grip the guide
element 15, holding it in position inside the suction pipe 13.
Preferably, at least one of the sets of sliders 31 and 32 is also
gripped, with the sliders engaging the guide element. The portion
of suction pipe between the intake end 13A and the intermediate
separator 19 is kept at a negative pressure through a suction mouth
14 set adjacent to the intermediate separator 19, on the intake
side of the suction pipe 13. The mouth 14 is connected to a suction
fan or the like (not shown).
[0079] The stem 15C which can be extracted from the guide element
15 has been previously pushed into its extracted position by means
of the air under pressure fed through the jaws of the separator
member 19. In this extracted position, the head 15E of the stem 15C
comes to be above the plane of the plates 59, which are opened to
enable passage of the head itself. Closing of the shaped plates 59
results in the stem 15C remaining engaged, through the hole 65
between the shaped plates 59, with the head 15E above the plates
themselves. This means that the stem 15C will remain in the
extracted position even in the absence of pressure inside the guide
element 15, and hence even when the jaws of the separator member 19
open. In this configuration, the stems 63 fixed to the plates 59
are up against the axis of the stem 15C and are at least partially
housed in a seat made in the stem below the head 15E of the latter,
in such a way as to reduce the radial encumbrance of the stems 63
for the reasons that will be clarified in what follows.
[0080] When the tubular article M has been completed by the
circular bed of needles 7 of the circular knitting machine 3, it is
unloaded from the needles and, as a result of the negative pressure
inside the suction pipe 13, is sucked in along the suction pipe 13
until it assumes the position shown in FIG. 18; i.e., until it
comes up against the intermediate separator 19. Movement of the
article M along the suction pipe 13 is guided by the guide element
15, the article M sliding in the free space between the inner wall
of the suction pipe 13 and the guide element 15. In order to enable
passage of the article M beyond the transverse surfaces on which
the sliders 31 and 32 act, the latter are closed and opened in an
alternating way, so that, during passage of the article M, only one
of the sets of sliders, either 31 or 32, is engaged with the guide
element 15. In this way, the tubular article M can pass beyond the
sections in which the sliders are set and can reach the position
illustrated in FIG. 18.
[0081] In order to cause the tubular article M to reach the output
end 13B of the suction pipe 13, in such a way that it bears upon
the wall formed by the shaped plates 59 in the position illustrated
in FIG. 19, the intermediate separator 19 is opened by moving the
jaws 21 and 22 away from one another. Suction through the mouth 14
can now be interrupted, whereas suction is activated through the
suction line connected, by means of the connection 57, to the
chamber 53 inside the mobile unit 39. This latter suction can be
activated also in the previous step, i.e., the one represented in
FIG. 18.
[0082] In this way, the tubular article M reaches the position
represented in FIG. 19, in which it bears upon the wall formed by
the shaped plates 59 in their closed configuration. Also in this
case, movement of the tubular article M is guided by the guide
element 15, which extends as far as the shaped plates 59. The
sliders 33, which were previously closed for supporting the guide
element 15 during opening of the jaws of the intermediate separator
19, are opened to enable passage of the article. Opening of the
sliders 33 can be synchronized with a new movement of closure of
the intermediate separator 19, in such a way that the guide element
15 will be all the time properly withheld in a substantially
central position inside the suction pipe 13. Alternatively, lateral
support of the guide element may be obtained, even at least in
part, by means of engagement with the hole in the wall defined by
the plates 59.
[0083] The function of the subsequent steps is to extract the
tubular article M from the suction pipe 13 and turn it inside out
to carry out the closing operation whereby the end edge B2 of the
article is sewn to form the closed toe thereof.
[0084] For this purpose, as may be seen in FIG. 20 (which
represents the end area alone of the suction pipe 13), the plates
59 are displaced by means of the rotating spindles 61 so as to
displace radially outwards the stems 63 fixed to the plates 59.
[0085] Since both the plates 59 and the stems 63 are above the
output end 13B and hence outside the suction pipe 13, the movement
of divarication of the stems 63 can be extended up to the point
where the latter are brought into an external radial position
(shown in FIG. 20) outside the encumbrance defined by the edge of
the suction pipe 13. In this position, the portion of fabric of the
article M close to the edge B1 is tensioned in such a way that it
is substantially outside the encumbrance of the suction pipe
13.
[0086] Once the stems 63 have engaged the tubular article M, the
telescopically extensible stem 15C of the guide element 15 can be
retracted inside the portion 15B of the latter, thus reducing the
pressure inside the part 15B of the guide element. 15. Retraction
of the stem is obtained by means of the effect of the extension
spring 15D. In FIG. 20 the stem 15C is illustrated in its retracted
position.
[0087] By means of a vertical movement downwards, as indicated by
the arrow f39, of the unit 39, the stems 63 are brought into a
position where they are set alongside one another externally and
laterally with respect to the output end 13B of the suction pipe
13. The tubular article is still engaged by the stems 63 and has
thus followed the latter, enveloping externally the suction pipe 13
in the area that surrounds the output end 13B of the latter. The
lowering movement of the unit 39 proceeds until the stems 63 have
been completely released from the tubular article M (FIG. 22).
[0088] In order to extract the tubular article M completely from
inside the suction pipe 13 and turn it inside out by bringing it
onto the outer surface of the suction pipe 13, the pushers 47 are
pressed against the tubular article M (FIG. 23), and the unit 39 is
at this point further displaced downwards, as indicated by the
arrow f39 (FIG. 24). In this way, the further movement downwards,
as indicated by the arrow f39, of the mobile unit 39 causes the
tubular article M to be drawn along the outer surface of the
suction pipe 13 until the unit 39 reaches the position illustrated
in FIG. 24. In this position, the tubular article M is completely
on the outside of the suction pipe 13. It is also turned inside out
with respect to the configuration in which it was knitted by the
circular knitting machine 3. The pushers 47 can be divaricated
again to release the tubular article M, which remains in the
position illustrated in FIG. 25 thanks to the elasticity of the
article itself (and in particular of its initial edge Bi), which
grips on the outer surface of the suction pipe 13. If the tubular
article M is particularly long, the stroke downwards of the unit 39
with the pushers 47 in the closed position can be repeated a number
of times, bringing the unit 39 each time back upwards after prior
opening of the pushers 47 to prevent the latter from drawing the
tubular article upwards again during the stroke upwards of the unit
39.
[0089] As may be seen in FIG. 24, the suction pipe 13 has two slits
13D which start from the output end 13B, i.e., from the edge of the
suction pipe 13, and which extend in a direction parallel to the
axis of the suction pipe for a certain stretch. The function of
these slits is to enable the brackets 73 to grip the tubular
article M and to slide it partially out of the suction pipe 13 for
closing the toe of the article by sewing. Before this operation is
carried out, however, the tubular article M may require angular
positioning.
[0090] In fact, the sewing line which is designed to close the toe
of the article must have a very precise orientation with respect to
the article itself, which normally presents pockets, namely
portions of fabric designed to form the heel area and the toe area
of the foot of the sock or stocking. The sewing line must assume an
extremely precise position with respect to these pockets of fabric.
In order to orient the tubular article properly before the sewing
operation, it is sufficient to provide, during knitting, marking of
the article, for instance by means of a few stitches of yarn of a
colour different from that of the yarn of the article. The marking
thus obtained can be detected by means of a photo-electric cell
(not shown) set in the proximity of the output end 13B of the
suction pipe 13. Appropriate angular orientation of the tubular
article M is at this point obtained by rotating, about its own
axis, the portion 13C of the suction pipe 13 by means of the
actuator 35. This rotation is the movement that brings the device
from the position of FIG. 24 to the position of FIG. 25. The two
figures differ, in fact, only as regards the different position of
the slits 13D made in the proximity of the output end 13D of the
suction pipe 13. The deviation in angular position between the two
figures represents the amount by which the portion 13C of the
suction pipe 13 is rotated with respect to the remaining part of
the pipe itself in order to bring the tubular article into the
correct angular position.
[0091] During this step of angular positioning, or in any case at
an appropriate instant, the unit 39 is brought back upwards until
it reaches the position illustrated in FIG. 26, the pushers 47
remaining in their retracted position, i.e., not in contact with
the tubular article, during said movement upwards.
[0092] Once the unit 39 has reached the top position illustrated in
FIG. 26, the pushers are closed again to press the tubular article
M against the outer surface of the suction pipe 13 in the proximity
of the output end 13B of the latter. Once the tubular article M has
been engaged again by pressing it against the outer surface of the
portion 13C of the suction pipe 13, the portion 13C can be rotated
again so as to bring the slits 13D into their original position,
namely on a plane which contains the axis of the portion 13C of the
suction pipe and is orthogonal to the plane of FIG. 26. This
movement of rotation of the portion 13C of the suction pipe 13,
again obtained by means of the actuator 35, does not cause an
angular movement of the tubular article M, in so far as the latter
is withheld by the pushers 47, which are advantageously coated with
a material having a high coefficient of friction. In this way, the
portion 13C of the suction pipe 13 rotates inside the tubular
article M in a sliding way, i.e., sliding on the inner surface of
the latter.
[0093] In the configuration of FIG. 26, the tubular article M is in
the correct angular position for the subsequent sewing operation,
and can therefore be picked up by the brackets 73 of the gripping
member 71. The brackets 73, which are brought up to one another,
are for this purpose lowered until they move inside the suction
pipe 13, into the position shown in FIG. 27, which represents a
longitudinal cross section of the suction pipe 13 according to a
plane orthogonal to the one represented in FIG. 26. The brackets 73
thus lie on a plane containing the axis A of the portion 13C of the
suction pipe 13, on which also the slits 13D lie. In this way,
divarication of the brackets 73, as indicated by the arrow f73 of
FIG. 27, is enabled for tensioning the edge B2 of the tubular
article M and thus bringing the two flaps of the edge to come close
to one another. The movement of divarication of the brackets 73 is
combined with a movement of lifting-up of the brackets, which thus
reach their final position, illustrated in FIG. 28. In the end
phase of the raising movement of the brackets 73, the pushers 47
can be brought up to the suction pipe 13 again for withholding the
tubular article M and thus causing longitudinal tensioning
thereof.
[0094] In this position, the edge B2 of the tubular article M has
been stretched or tensioned by means of the brackets 73 in such a
way that the two flaps of the edge have been aligned to one
another. The brackets 73 have been brought into a vertical position
such that their bottom ends are slightly above the rectilinear bars
77 and 79. The latter can thus be brought up to one another to grip
the tubular article M in an appropriate position of the edge B2.
This is schematically represented in FIG. 29, which shows a
longitudinal cross section according to a plane orthogonal to that
of FIG. 28. The rectilinear bar 77 has been brought up to the fixed
bar 79. In FIG. 28, L1 and L2 designate the two flaps of the edge
B2 that have been brought close to one another as a result of the
tensioning of the edge B2 performed by the brackets 73 of the
gripping member 71. The article can be tensioned by means of a
slight movement downwards of the unit 39 with the pushers 47.
[0095] FIG. 29A is a schematic enlargement of the area in which the
flaps of fabric L1 and L2 forming the edge of the tubular article
that is to be closed can be seen. As shown in the schematic section
of the fabric, the latter presents a series of rows X2 set above
the bars 77 and 79, some of these rows being made with a yarn
thicker than that of the other rows. Said thicker rows form a
portion of fabric of greater thickness, which is brought to bear
upon the bars 77, 79 set alongside one another. The bars 77, 79 do
not necessarily have to be pressed against the fabric, which,
instead, is appropriately left free to slide so as to be tensioned
transversely. Retention in the longitudinal direction is guaranteed
by the fact that the portion of fabric of greater thickness
obtained with the thicker yarn, designated by FG in FIG. 29A, bears
upon the bars 77, 79. The portion of the tubular article made up of
the rows X2 will be removed in the subsequent cutting operation,
and is consequently normally produced with a yarn of poorer quality
than the yarn of the remaining part of the tubular article M.
[0096] During the sewing operation, the edge formed by the rows X2
may be kept raised by means of suction through a suction mouth
associated to the sewing machine 95 and designated, as a whole by
102 in FIGS. 33 and 34.
[0097] With a movement in the direction indicated by the arrow f83,
the comb-like structure 83 is at this point pushed towards the
tubular article M until the teeth 85 of the comb-like structure 83
penetrate inside the stitches or loops of the row that is set
facing the comb-like structure 83, namely the row that is directly
beneath the rectilinear bars 77 and 79. As may be seen in the
diagram of FIG. 29A, the loops of this row (designated by X1) have
a greater length than the remaining loops of the article in order
to enable convenient insertion of the teeth 85 of the comb-like
structure 83.
[0098] The movement in the direction indicated by the arrow f83 of
the comb-like structure 83 is controlled by the actuators 89
described previously (see FIG. 6) and not illustrated, for reasons
of clarity, in FIG. 29. The closing movement of the rectilinear
bars 77 and 79 and the subsequent movement of the comb-like
structure 83 are represented in the sequence of FIGS. 30 to 32,
which show the aforesaid movements in schematic plan views.
[0099] Once the teeth 85 of the comb-like structure 83 have
penetrated the individual loops of the respective row in the
tubular article M, the mobile rectilinear bar 77 can be retracted
to enable insertion of the members of the sewing machine 95, which
performs sewing along the loops of the row of stitches underneath
the row inside which the teeth 85 of the comb-like structure 83
have penetrated. The sewing operations are schematically
illustrated in FIG. 33.
[0100] FIG. 33 shows the needle 96 of the sewing machine 95, the
mouth 99, and the crochet 101. Also visible is the comb-like
structure 83, which is inserted inside the corresponding row of
stitches or loops of the tubular product M. The sewing area is
shown enlarged in FIG. 34. Clearly visible in the latter figure is
how the comb-like structure 83 and the corresponding teeth 85 are
made up of the two portions 83A and 83B (shown separate from one
another in the perspective view of FIG. 16), which are connected
together and between which the blade 87 is set, said blade, in this
configuration, being in a retracted position, namely a position set
back with respect to the teeth 85.
[0101] Movement of the members of the sewing machine, and in
particular of the needle 96 and the crochet 101 which feeds the
sewing thread F, is shown in FIG. 35. In this example of
embodiment, the needle 96 is a so-called piston needle, i.e., a
needle provided with an opening and closing member 96A. A needle of
this kind is in itself known from the state of the art, in
particular from the prior patents cited in the introductory part of
the present description. It is, however, possible to use also other
types of needles and/or crochets. For example latch needles or eye
needles may be used. The sequence of the sewing operations may be
clearly seen in FIG. 35 and is in itself known for other types of
applications, consequently, no detailed description is required
herein.
[0102] It should however be noted that the pitch of the seam made
by the sewing machine 95 with the needle 96 is smaller than the
pitch of the comb-like structure 83 and of its teeth 85, i.e.,
smaller than the pitch of the loops of the row X1. In particular,
it is possible to envisage that the pitch of the seam will be equal
to one half or to one third of the pitch of the loops of the row
X1, and hence of the teeth 85 of the comb-like structure 83.
[0103] FIGS. 36, 37 and 38 show the subsequent step of cutting of
the loops of the row X2, inside which the teeth 85 of the comb-like
structure 83 have been inserted. Before carrying out this cutting
operation, the flaps L1 and L2 of the tubular article M, which are
by now joined together by the seam designated by C in FIGS. 36 to
38, are gripped and withheld by the retention bars 105 of the
retention member 103 carried by the sewing machine 95 which has
made the seam C. This makes it possible to withhold the tubular
article M even after the cutting operation has been performed.
Cutting is performed by moving the blade 87 housed inside the
comb-like structure 83 so as to bring it from the position of FIG.
36 to the position of FIG. 37. Thanks to this movement, the blade
87 cuts all the loops of the row X2 inside which the teeth 85 of
the comb-like structure 83 were previously inserted.
[0104] At this point, the comb-like structure 83 can be moved away
from the article to reach the position shown in FIG. 38, whilst the
tubular article M is withheld by the retention bars 105 provided
for this purpose and previously brought up to one another. The
residue of cut yarn above the seam C is removed by the removal
system 107, which in FIG. 39 is schematically represented by a
brush with a horizontal axis, parallel to the bars 105, but which
may actually have the configuration shown in FIG. 40. The enlarged
representation of FIG. 41 shows the action mechanism of the brush
109, in this case with a vertical axis, for removal of the residue
of yarn, designated by FR in the enlarged representation of FIG.
41.
[0105] Once said sewing, cutting and yarn-residue-removal
operations have been completed, the article M can be removed from
the device, after the article has been turned inside out again to
assume its final configuration corresponding to the one in which it
was produced by the circular knitting machine 3. For this purpose,
reverse operations are performed with respect to the ones
previously carried out for turning the article inside out by means
of the movement of the unit 39 and the action of the sliders 47.
Negative pressure is at this point applied inside the suction pipe
13 through a suction mouth 16 (FIG. 43) in such a way that the
article, with its toe closed by the seam C, is sucked through the
mouth 16 and is removed from the device.
[0106] Removal is facilitated by the movement of the part 15B of
the guide element 15 with respect to the part 15A, about the hinge
axis 17, so that the part 15B of the guide element comes up against
the inner wall of the suction pipe 13 on the opposite side with
respect to the one where the suction mouth 16 is set, leaving a
wider passage for transit of the sewn tubular article M towards the
suction mouth 16.
[0107] Once the above operations have been completed, the device
returns to the configuration represented in FIG. 17 for sewing of a
subsequent tubular article M, which, in the meantime, has started
its formation on the circular knitting machine 3.
[0108] It is understood that the drawings only illustrate a
possible embodiment of the invention given purely to provide a
practical demonstration of said invention, which may vary in its
embodiments and arrangements without thereby departing from the
scope of the underlying idea. The possible presence of reference
numbers in the attached claims has the sole purpose of facilitating
reading thereof in the light of the foregoing description and of
the annexed drawings, and in no way limits the scope of protection
defined in the claims.
* * * * *