FIELD OF APPLICATION
[0001] The present invention relates to an automatic unit adapted to carry out programmable
sewing on the front part of trousers, jeans and of the type with five pockets.
[0002] More precisely, the present invention relates to an automatic unit that enables programmable
sewing to be carried out both on the right front panel of male trousers and on the
left front one of female trousers during the operation of fixing the front fly of
the trousers.
[0003] Compared to the known solutions, the automatic working unit according to the invention
aims to solve the problem of changing over the format during fly manufacture between
male trousers and female trousers and in addition the same working unit is more versatile
compared to the known solutions, as the manufacture of flies both with buttons and
with a zipper is made possible.
[0004] The present invention is advantageously applied in the sector of machines for industrial
sewing of clothing items and in particular in the field of sewing machines for the
manufacture of flies of trousers such as jeans or the type with five pockets.
STATE OF THE ART
[0005] It is known that automatic sewing machines adapted to carry out programmed sewing
in a "J" pattern on trousers such as jeans or the type with five pockets, a process
that is necessary to produce a trouser fly with buttons or a zipper, are produced
according to at least two possible methods, based on the following possible types
of manufacturing that can be performed with a dedicated automatic unit for:
- a) manufacturing only male or unisex trousers with sewing carried out on the right
front panel, while it is not possible to carry out sewing on women's trousers on the
left front panel. In this case the use of a mechanical system that relies on two grippers
to align the panel with a sewing head is envisaged;
- b) manufacturing both male and female trousers, though in this case it does not have
any system for mechanical alignment of the panel with the sewing head.
[0006] It should be borne in mind that for the types of manufacturing mentioned, reference
is made to a method which implies that the material is loaded with an upper side thereof
exposed on a loading surface and hence the stitches made with the upper sewing head
are the ones that will remain exposed on the trousers.
[0007] With the first type of unit for sewing in a "J" pattern, the production of the fly
can be carried out only on men's or unisex trousers, since the programmable sewing
can be carried out only on the right front panel. In this case, the sewing head is
at the end of the loading surface, whilst a loader of the right front panel is positioned
on the opposite side.
[0008] In between the sewing head and the loader there is a system of mechanical grippers
that are used to position the material and maintain it in position during loading.
[0009] The operating cycle carried out with this first type of sewing unit takes place in
five steps, namely, the following:
- 1. in a first step an operator starts loading the panel onto the loading surface,
positioning the edge of the panel against the mechanical grippers while the latter
and the loader are positioned in a rest point.
- 2. in a second step the operator activates a cycle of shifting the gripper assembly,
the grippers are opened, they are shifted from a rest position to a material locking
position and upon reaching the latter position, the mechanical grippers are automatically
closed so as to lock the material, whereas the loader is still positioned in its rest
point.
- 3. in a third step the loader shifts the material, maintained stationary by the mechanical
gripper assembly, into the area of the sewing head, where the shifting is carried
out only if the sewing head is in conditions to receive the load of material.
- 4. in a fourth step the sewing head locks the material just loaded by means of its
own internal gripper and the loader opens the mechanical grippers;
- 5. in a fifth step the loader returns to its starting point, the mechanical gripper
assembly is shifted into the rest position and the grippers are closed again. The
sewing head locks the material with its own external gripper and starts the programmed
sewing cycle and it is only at this point that the operator can start loading the
next material to be sewn onto the loading surface at the mechanical grippers.
[0010] This solution poses the limit of being able only to carry out the sewing on the right
front panel of men's trousers, as the mechanical system that enables the loader to
be moved is fixed onto the right part of the loading surface and this precludes being
able to load a left front panel for women's trousers.
[0011] In the second case, the automatic unit can carry out the manufacture of both male
and female trousers, since the programmable sewing is carried out on both the right
front and left front panels, though in this case it does not have any system for mechanical
alignment of the panel with the sewing head.
[0012] In this second case the sewing head is at the end of the loading surface; positioned
on the opposite side there is instead a gripper/pad that is used as a loader and it
should be noted that in between these two elements there is no mechanical gripper
or mechanical alignment system for positioning the material during loading.
[0013] The operating steps in this second case are the following:
2.1) in a first step an operator starts loading the material to be sewn on the loading
surface, and positions one edge of the panel relative to reference marks. The loader
is positioned in a rest point;
2.2) in a second step the operator activates a cycle of locking the material, a mechanical
pad is closed against the loading surface to lock the material, whereas the loader
is still positioned in the rest point;
2.3) in a third step the loader shifts the material, maintained stationary by the
mechanical pad, into the area of the sewing head and the shifting is carried out only
if the sewing head is in conditions to receive the load of material;
2.4) in a fourth step the sewing head locks the material just loaded by means of its
own internal gripper thereof and the loader opens the mechanical pad;
2.5) in a fifth step the loader returns to the starting point, whilst the sewing head
locks the material with its own external gripper and starts the programmed sewing
cycle. Only at this point can the operator start loading the next material to be sewn
on the loading surface, again making reference to the reference marks.
[0014] As previously specified, this automatic unit enables sewing to be carried out both
on the right front panel of male trousers and the left front one of female trousers,
but in this case the unit totally lacks a system for mechanical alignment of the panel
with the sewing head; a suction device for locking the material, a system for mechanical
alignment, or any integrated system with double independent adjustable pins within
the loading surface are likewise totally absent from the loading surface.
[0015] All this implies the consequence of a processing that is much more imprecise than
the one obtained with machines equipped with aligners and suction means for locking
the material placed on the loading surface.
DESCRIPTION OF THE INVENTION
[0016] The present invention aims to provide an automatic unit which enables programmable
sewing of a fly to be carried out both on the right front panel of male trousers and
on the left front panel of female trousers during an operation of fixing the front
fly, thus creating a condition able to eliminate or at least reduce the drawbacks
highlighted above.
[0017] The invention aims in particular to provide an automatic operating unit that enables
a programmable sewing of a fly to be carried out on panels of both male and female
trousers. The fly can be combined with a zipper or buttons, based on the required
style.
[0018] Another object of the invention is to propose an automatic unit which enables an
operator to load the right front panel on the loading surface, with one leg of the
trousers falling on the left loading side, whereas the left front panel to be sewn
is loaded by the operator spread out on the loading surface with the leg of the trousers
falling on the right loading side.
[0019] This is obtained by means of an automatic unit for a programmable sewing of a trouser
fly whose features are described in the main claim.
[0020] The dependent claims of the solution in question outline advantageous embodiments
of the invention.
[0021] The main advantages of this solution regard a loading device comprising a mechanical
system provided with a double row of pins, whose positions and movements are independent
from one another.
[0022] A further advantage offered by the automatic unit according to the invention is that
of permitting a programmable sewing of a fly to be carried out both on the male right
front panel and on the female left front panel.
[0023] According to the invention, on the loading surface there is a first pair of rows
of pins for the right front panel for a male fly and a second pair of rows of pins
for the left front panel for a female fly.
[0024] One advantage offered by the automatic unit according to the invention consists in
the fact that this system is integrated within the loading surface, and therefore
in the rest position it does not interfere with the step of loading the material towards
the sewing head.
ILLUSTRATION OF THE DRAWINGS
[0025] Other features and advantages of the invention will become evident upon reading the
following description of one embodiment of the invention, provided by way of nonlimiting
example with the aid of the drawings illustrated in the appended figures, of which:
- figure 1 represents a schematic view of an automatic unit which enables a programmable
sewing of a fly to be carried out on the right front panel of male-type trousers;
- figure 2 represents a schematic view of an automatic unit which enables a programmable
sewing of a fly to be carried out on the left front panel of female-type trousers;
- figures 3 and 4 illustrate detailed schematic views of assemblies for positioning
front panels consisting respectively of a front right assembly for male trousers and
a front left assembly for female trousers, according to the details E of figures 1
and 2;
- Figure 5 illustrates a schematic plan view of an automatic unit for a programmable
sewing of a fly on a right front panel of male trousers;
- figure 6 illustrates a schematic plan view of an automatic unit for a programmable
sewing of a fly on a left front panel of female trousers;
- figure 7 represents a schematic side view of an automatic unit for a programmable
sewing of a fly of a right front panel of male trousers according to the section line
B-B in figure 5;
- figure 8 represents a schematic front view of the same automatic unit for a programmable
sewing of a fly of a right front panel of male trousers according to the section line
A-A in figure 5;
- figure 9 is a detailed schematic view of the detail C in figure 7;
- figure 10 illustrates a view of a material loading gripper provided with a panel conveyor
blade, in the open position;
- figure 11 is a view showing the positioning of fixed and adjustable pins according
to the detail D in figure 5;
- figures 12 and 13 represent schematic views of two steps of a manufacturing cycle
for a fly with buttons in the step of loading buttons and of loading a right panel
of men's trousers, respectively;
- figure 14 illustrates a schematic view of a step of a manufacturing cycle with loading
of a right panel of men's trousers with a zipper.
DESCRIPTION OF AN EMBODIMENT OF THE INVENTION
[0026] Making reference to the appended figures, 20 generally indicates an automatic unit
illustrated in figure 1 which enables a programmable sewing of a fly to be carried
out on a right front panel of male trousers, whereas 21 generally indicates an automatic
unit illustrated in figure 2 which enables a programmable sewing of a fly to be carried
out on a left front panel of female trousers.
[0027] Taking initially the case of the unit represented in figure 1 and related to the
sewing of a fly on the right front panel of male trousers, 22 indicates a work surface
which, in a plan view, has a substantially rectangular conformation, as better represented
in figure 5.
[0028] As represented in figure 10, there is a loading device 23 positioned and operating
on the work surface 22, the loading device 23 comprising a material loading gripper
24 hinged to a conveyor plate 24' for conveying the panel and which is movable relative
thereto by means of an actuator 25 that enables the opening or closing of the gripper
itself with a folding movement relative to the conveyor plate 24', as better represented
in figure 10.
[0029] According to the embodiment illustrated in figure 1, a sewing head 26 is positioned
on a side opposite the work surface 22 relative to a gripper 24, and more in particular
it is located in a terminal sector of that surface and in a position that is substantially
symmetrical relative to a longitudinal axis of the work surface itself.
[0030] This particular arrangement, as we will see below, enables the same automatic unit
to be used both for programmable sewing of a fly on the right front panel of male
trousers, as represented in figures 1 and 5, and for programmable sewing of a fly
on the left front panel of female trousers, as represented in figures 2 and 6.
[0031] In the embodiment represented in figures 1 and 2, 3 and 4 and 5 and 6, one can note
that the work surface 22 is intercepted by two groups of pins indicated, respectively,
by 27 and 28, used respectively for processing in a sector for male trousers or in
a sector for female trousers of the work surface 22.
[0032] Each of said groups of pins 27 and 28 is composed of two parallel rows of pins, with
each row independent of the other, and of which a first row of pins 29 for positioning
buttons is movable only in a vertical direction by means of actuators 32 and a second
row of adjustable pins 30 for positioning the panel is movable both vertically and
longitudinally by means of actuators 32, as better represented in figures 9 and 11.
[0033] The adjustable pins 30, as represented in figure 9, can be shifted both from a retracted
position to a forward position by being moved along special slots from which they
project, and in a vertical direction from an ejected position to a retracted one relative
to the work surface 22, being mounted on a common support bar that is movable and
adjustable by means of said actuators 32, which are arranged on two axes.
[0034] Positioned in proximity to the actuators 32 there is moreover a device for releasing
and adjusting the rows of pins.
[0035] Furthermore, positioned in proximity to the rows of pins 29 and 30 there are suction
holes 31 which allow retaining the fabric in collaboration with the aforesaid gripper
24.
[0036] The working unit according to the invention operates by means of a fabric loading
system that relies on the aforesaid two groups of pins 27 and 28, each of which is
composed of two independent parallel rows, namely, a first row of fixed pins 29 for
positioning a set buttons and a second row of adjustable pins 30 for positioning the
panel, whose position and movement are independent of each other.
[0037] With reference to figure 1, on the loading surface 22 there is a pair of rows of
pins 27 for the right front panel (men) and a pair of rows of pins 28 for the left
front panel (women).
[0038] One of the advantages proposed by the invention regards the fact that this system
is integrated into the loading surface, and thus in the rest position it does not
interfere with the step of loading the material towards the sewing head.
[0039] According to the embodiment represented in figure 11, the first row of pins 29 has
a fixed longitudinal position with all of the pins aligned relative to the movement
of the loader comprising the conveyor plate 24' of the panel and the fabric loading
gripper 24.
[0040] In the working position, these pins have the possibility of coming out slightly from
the loading surface to enable the operator to align the material (buttons) against
the same and maintained in position by a vacuum system represented by the suction
holes 31.
[0041] The second row of pins 30 has an independent movement relative to the first row of
pins 29 and the possibility of changing the working position relative to the position
of the first row.
[0042] In the working position, the pins 29 and 30 have the possibility of coming out from
the loading surface to enable the operator to align the front panel to be sewn with
the sewing head 26, based on the required sewing style, which can be an operating
cycle for a zipper or for buttons.
[0043] The panel to be sewn in the case of a programmable sewing with a loading cycle with:
- buttons, it uses both rows of pins 29 and 30 present in the loading surface and in
this case the front panel is positioned above the previous loading cycle and above
the previous row of pins;
- zipper, it uses only the second row of pins, which are adjustable in their longitudinal
working position.
[0044] The first row of pins 29 is maintained in the rest position thereof, because in this
loading cycle the lower part with the zipper has already been fixed to the front panel,
and this is directly loaded against the second row of pins 30.
[0045] Figures 12 and 13 represent two steps of the cycle of manufacturing a fly with buttons,
respectively in the steps of loading the buttons and loading the right panel of men's
trousers, whereas figure 14 represents one step of the cycle of manufacturing a fly
with zipper in the step of loading the zipper on a right panel of men's trousers.
[0046] According to the invention is it further envisaged that in the automatic unit there
is also a vacuum system that relies on the suction holes 31, which enable the upper
panel to be maintained in position until the loading jig is closed and conveys the
material below the sewing head.
[0047] The two rows of pins 29 and 30 located on the sewing unit can operate in a specific
and differentiated manner for men's and women's trousers and the operation thereof
is controlled by a programmable system connected to the process controller (PLC).
[0048] The mechanical movement system that allows the pins 29 and 30 to be made to come
out and go back inside relies on actuators 32 which move the groups into the established
positions.
[0049] The working position refers to the moment in which the terminal part of the pins
comes out from the loading surface, whereas the rest position refers to the moment
in which the terminal part of the pins is positioned inside the loading surface.
1. An automatic sewing unit (20, 21) adapted to carry out a programmable sewing of a
trouser fly, comprising:
a) a work surface (22) on which a loading device (23) for conveying a trouser panel
is positioned and operates;
b) a sewing head (26) positioned on a side opposite the work surface (22) relative
to the loading device (23);
characterised in that said loading device (23) comprises a material loading gripper (24) hinged to a conveyor
plate (24') for conveying a fabric panel and which is movable relative to the gripper
(24) by means of an actuator (25) that enables the opening or closing of the gripper
itself with a folding movement relative to the conveyor plate (24') and
in that acting on said work surface (22) there is a first row of pins (29) aligned with one
another and movable only in a vertical direction relative to the work surface (22)
and a second row of pins (30) movable both in a vertical direction and in a horizontal
direction relative to the work surface (22), said pins (29, 30) being able to be shifted
vertically from a working position wherein the pins come out of holes fashioned in
the work surface (22) and a rest position wherein the pins go back inside the work
surface (22).
2. The automatic unit (20, 21) according to claim 1, characterised in that said pins (30) movable both in a vertical direction and in a horizontal direction
relative to the work surface (22) can be shifted both from a retracted position to
a forward position by being moved along special slots from which they project, and
in a vertical direction from an ejected position to a retracted one relative to the
work surface (22), provided with special holes, being mounted on a common support
bar that is movable and adjustable by means of actuators (32) arranged on two axes.
3. The automatic unit (20, 21) according to one of the preceding claims, characterised in that suction holes (31) for retaining the material are arranged in proximity to the rows
of pins (29, 30).
4. The automatic unit (20, 21) according to one of the preceding claims, characterised in that it comprises a material loading system that includes said pins.
5. The automatic unit (20, 21) according to one of the preceding claims, characterised in that on the loading surface (22) there is a pair of rows of pins cooperating with a right
front panel of male trousers and a pair of rows of pins cooperating with a left front
panel of female trousers.
6. The automatic unit (20, 21) according to claim 1, characterised in that the pins of the first row of pins (29), in the working position, project beyond the
loading surface (22) to enable the operator to align the material against the pins
themselves, the material being held in position by a vacuum system comprising suction
holes (31).
7. The automatic unit (20, 21) according to one of the preceding claims, characterised in that said second row of pins (30) has an independent movement relative to the first row
of pins (29).