EP3736368B1

EP3736368B1 - Automatic unit for programmable sewing of a trouser fly

Info

Publication number: EP3736368B1
Application number: EP20173747.5A
Authority: EP
Inventors: Dario MORANDIN
Original assignee: TorMec Ambrosi SRL
Current assignee: TorMec Ambrosi SRL
Priority date: 2019-05-10
Filing date: 2020-05-08
Publication date: 2021-11-24
Anticipated expiration: 2040-05-08
Also published as: EP3736368A1; IT201900006726A1

Description

FIELD OF APPLICATION

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.
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.
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.
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

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.

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.
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.
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.
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.

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.
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.
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.
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.

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.
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.
Document GB 2174113 discloses an automatic assembly for sewing a flypiece to a continuous slider fastener chain including a sewing machine, a gapping device from which the continuous chain having element-free gaps formed at regular intervals therealong is fed to the sewing machine, and a flypiece deliverly system for successively retrieving individual flypieces one at a time from a stack and successively advancing to the sewing machine. The flypiece delivery system is arranged such that successive flypieces are sewn to the fastener chain virtually even with the rate at which gapped chain is delivered from the gapping device.
Document US 4911091 A discloses a sewing apparatus for attaching a strip of cloth with a zip-fastener component to a trouser forepart. To attach a strip of cloth provided with a zip-fastener component to each of two trouser foreparts, the edge of the trouser forepart is folded over before being joined to the strip of cloth. The trouser forepart with the folded-over edge and the strip of cloth are positioned relative to one another in a position which they occupy after being sewn together. Subsequently, this sewing takes place in a clamping fixture in a single sewing operation. The purpose of this measure is to attach the strip of cloth and zip-fastener component to a trouser forepart with the minimum possible effort.
Document CN 206783942 U discloses a button sewing locating device that has a working table provided with a sewing machine, a locating device provided with a base plate, and a liner plate fixed above a supporting plate, where an outer end of the supporting plate is provided with a locating rocker.

DESCRIPTION OF THE INVENTION

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.
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.
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.
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.
The dependent claims outline advantageous embodiments of the invention.
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.
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.
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.
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

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

With reference to the appended figures, reference sign 20 generally indicates an automatic unit as 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.
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.
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.
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.
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.
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.
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.
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 work 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.
Positioned in proximity to the actuators 32 there is moreover a device for releasing and adjusting the rows of pins.
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.
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.
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).
One of the advantages proposed by the invention regards the fact that this system is integrated into the loading surface, and thus in a rest position it does not interfere with the step of loading the material towards the sewing head.
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.
In the work 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.
The second row of pins 30 has an independent movement relative to the first row of pins 29 and the possibility of changing the work position relative to the position of the first row.
In the work 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.
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. 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.

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.
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.
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).
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.
The work 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 work surface.

Claims

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);
whereby 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'), characterised in that acting on said work surface (22) there is a pair of rows of pins comprising 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 between a work 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) .
The automatic unit (20, 21) according to claim 1, characterised in that said pins (30) movable both in the vertical direction and in the horizontal direction relative to the work surface (22) can be shifted both from a retracted position to a forward position by being moved along slots from which they project, and in the vertical direction from the work position to the rest position relative to the work surface (22), provided with holes, being mounted on a common support bar that is movable and adjustable by means of actuators (32) arranged on two axes.
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).
The automatic unit (20, 21) according to one of the preceding claims, characterised in that on the work surface (22) there is a pair of rows of pins for cooperating with a right front panel of male trousers and a pair of rows of pins for cooperating with a left front panel of female trousers.
The automatic unit (20, 21) according to claim 1, characterised in that the pins of the first row of pins (29), in the work position, project beyond the work surface (22) to enable the operator to align the material against the pins, the material being held in position by a vacuum system comprising suction holes (31) .
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).