| JP2003311058A | 2003-11-05 | |||
| US5588384A | 1996-12-31 | |||
| CN110965217A | 2020-04-07 | |||
| JP2003311058A | 2003-11-05 |
| CLAIMS 1.A folding device (10) designed to fold two end flaps of material adapted for forming belt loops (P) to be applied on items of clothing or the like, comprising two rotating folding units that act by rotating reciprocally inversely, each of which comprises at least one pair of fork-like pins (13, 14) parallel and rotating for each edge of material of the belt loop to be folded over, said pins being able to be angularly rotated by means of a rotation shaft (19) so as to undergo axial rotations by means of respective independent rotating devices (15, 16), each of said pairs of pins comprising a first pin (14a), which in the rest position is positioned in parallel to and near a second pin (14b) and rotates about the axis of the latter in order to be placed from a first position of gripping the end of the belt loop (P) to a position of complete folding of the belt loop, after a rotation according to a predetermined angle, every pair of fork-like pins (13, 14) being associated with a movement unit of which a third pin (17) is part, which is partially shaped and parallel to the first and second pins (14a, 14b), characterised in that the third pin (17) is applied on the edge of an annular bush (18) that can rotate about said shaft (19) which generates a rotation transmitted to the rotating devices (15, 16). 2.The folding device (10) according to the preceding claim, characterised in that said pin (17) is "S" shaped, and because of its conformation rotates eccentrically about the axis of the same pin (14b), disposed on an axis parallel to the rotation axis of the rotating device (16). 3.The folding device (10) according to one of the preceding claims, characterised in that said pin (17) consists of a metal rod with a median broken portion (11') that forms two portions with axes parallel to those of the pins (14a, 14b), said conformation imparting to the pin (17) an eccentric rotation relative to the axis of the pin (14b). 4.The folding device (10) according to one of the preceding claims, characterised in that the same annular bush (18) is provided with a pair of concentric arch-shaped slots (20, 21) disposed radially as an arc of a circle and offset from each other . 5.The folding device (10) according to claim 4, characterised in that a set screw (22) solidly joined to the shaft (19) projects from the first slot (20), whereas the second slot (21) is intercepted by a further fixed set screw (23) solidly joined to a locking plate (24) fixed onto the machine body by means of a locking element (25). 6.The folding device (10) according to claim 5, characterised in that said set screws (22, 23) operate in the respective offset arch-shaped slots (20, 21) so as to enable a controlled rotation of the pin (17) synchronised with the movements of the shaft (19), which in turn drives the rotation of the pins (14a, 14b). 7.The folding device (10) according to the preceding claims, characterised in that the action of the set screws (22, 23) is configured so that the rotation of the shaft (19) imparts a main rotation both to the pin (14a) that rotates about the axis of the pin (14b), and to the set screw (22) which operates inside the slot (20), and a secondary rotation of the annular bush (18), whose rotation begins when the set screw (22) has shifted angularly until reaching the opposite end of the slot itself in opposition to the set screw (23), which acts as a limit stop in the slot (21). 8.The folding device (10) according to any one of claims 5-7, characterised in that the bush (18) imparts to said pin (17), applied on the annular edge thereof, an eccentric rotation due to the rotation of the bush itself about the axis of the shaft (19) which moves the pin (17) from its starting point, distal relative to the material, to its final point, which is proximal relative to the material in opposition to the set screw (23), which acts as a limit stop in the offset slot (21). 9.The folding device (10) according to any one of claims 4-8, characterised in that the total eccentric rotation allowed to the pin (17) is given by the rotation of the shaft (19) on the axis of the pin (14b) from which the length of the slot (20) formed on the bush (18) is subtracted. 10. The folding device (10) according to any one of claims 5-8, characterised in that when the set screw (22) arrives in contact with the end opposite the starting point in which it is positioned in the slot (20), it imparts a rotation to the annular bush (18) on which the pin (17) is inserted, in opposition to the set screw (23) acting as a limit stop. |
TROUSERS, SKIRTS OR THE LIKE"
FIELD OF APPLICATION
The present invention relates to a device adapted to fold belt loops to be sewn onto the edges of items of clothing, such as trousers, skirts or the like.
More in particular, the device according to the invention is designed to retain flaps of fabric or loops to be folded over by means of a folding system with adjustable elements, with the addition of a further double rotational movement for each side of the belt loop to be formed and applied on trousers or other items of clothing.
The folding device according to the invention represents an important development compared to the known solutions, as it enables the length of the flaps folded over inside it to be reduced to a minimum. By virtue of this, following the final washing cycle it will be possible to avoid the subsequent operation of cleaning or trimming the folded material.
This device thus makes it possible to produce belt loops with the internal flaps folded over "cleanly", i.e. devoid of unattractive fraying.
The present invention is advantageously applied in the sector of industrial devices for the manufacture of items of clothing, in particular for the production of jeans-style trousers or skirts or other similar applications on items of clothing of various kinds.
PRIOR ART
It is known that different types of machines are used to manufacture items of clothing, based on the task that they must perform. For example, in the sector of the production of jeans-style trousers or skirts, use is made of machines that automate the processes of forming the various pieces to be put together and the application thereof on the base fabric which, in the specific case, can be represented by trouser portions on which the belt loops are applied.
Among the various types of machines for the manufacture of items of clothing there are also automatic machines for the application of belt loops.
Such machines enable the forming and application of belt loops on a base fabric and comprise mechanical operating assemblies that enable the preparation of belt loops folded over at the outer flaps thereof, and which operate according to two main operating conceptions: a)the belt loop strip is pulled and cut to the desired size prior to the arrival of the loader. At this point a system of grippers keeps the strip firmly in position until the moment in which the outer flaps are folded over; b)the belt loop strip is pulled to the desired size and awaits the arrival of the loader, and when the loader has arrived the strip is cut while a central gripper keeps the strip firmly in position, until the moment in which the outer flaps are folded over.
The two methods substantially differ in the sequence of movements in which the device operates to prepare the belt loop, that is, when the device for pulling the strip of material begins to work, or when the loader positions the rotation pins inside the strip and when the cutting of the strip of material takes place.
The point all these automatic belt loop attachment units have in common consists in the fact that, after the material is cut, the formation of the belt loop takes place, whereby the edges thereof are folded over inwardly.
In order to do this, as represented in figures 1 to Id, the loading device comprises, in the front part thereof, two pairs of rotating fork-like pins A and B adapted to form the classic belt loop P, applied like a patch, by taking it and folding it over at the two ends thereof.
In their starting position, said rectilinear rotating fork-like pins A and B are arranged on horizontal axes and positioned parallel, one above the other, that is, the main lower pin is placed almost in contact with the lower edge of the upper pin.
The distance between the two rotating pins is adjustable based on the thickness of the material to be folded, and, normally, to allow the material to remain in its original position, during the insertion of the belt loop between the two pins, this distance is adjusted so as to keep the friction of the material against the aforesaid rotation pins at a minimum during insertion but with considerable friction during rotation in order to prevent the possibility of the material slipping during the rotation of the rotating pins.
The loader positions the two pins until the strip of material is completely inserted inside them, and, after this step, the more or less simultaneous rotation of the outer flaps of the material begins while the central device has already locked the belt loop strip in place. This operation is performed by rotating the upper pin by 270 degrees about the axis of the main lower pin, whilst the main lower pin rotates about its longitudinal axis.
The rotation step ends when the two rotating pins are positioned alongside each other horizontally, and in this case the main lower pin is positioned on the outside, whereas the upper one is positioned towards the inside.
In every loader there are two pairs of pins positioned at the two ends of the belt loop.
By rotating simultaneously in a mutually opposite direction, the pair of rotation pins allow the outer flaps to be folded over towards the inside of the belt loop.
During the folding step, therefore, the simultaneous rotation of the outer flaps causes the strip of material to become tensioned, despite the presence of the central locking device, and, especially in the case of elastic or very stiff materials, this fact entails that the flaps of folded material tend to slip off the internal pin.
This defect is exacerbated if the length of the folded over flaps is too short or if the tension accumulated in the material during the rotation is not contained.
In order to prevent the belt loop from slipping and avoid the related quality issues, it is necessary for the internal pin to be dimensioned so as to have sufficient material beyond the profile thereof, in order to lock the flap of folded over material against the lower surface of the upper strip, since the tension of the material itself would tend to cause it to slip out of the pin that applied the fold.
The final required length of the folded over flap of material is thus calculated on the basis of different parameters:
- the type of material and the thickness thereof;
- the mechanical system applied to rotate the two flaps;
- the speed of rotation of the pins and the friction thereof on the material.
In order to overcome all these problems, therefore, the common practice is to greatly increase the length of the folded over material. However, this solution gives rise to a further problem, namely that between the stitching applied to fix the belt loop in the required point and the free end of the internal folded over flaps, the fibres of material that are not held in place by the stitches during washing open up, that is, the ends come separated, causing fraying.
The drawback arising from this consists in the fact that the separated and frayed edge of the folded over ends of the belt loop becomes visible beneath the upper profile of the belt loop, with the consequence that it is necessary to intervene with a further manual cleaning operation, with the associated costs, in order to cut off this frayed material and avoid contestations regarding the execution of the sewing operation or the quality of the trousers.
Document JP 2003311058 A discloses a belt loop piece feeding device for a sewing device aiming to perform a bar tacking sewing by folding back both end parts of a belt loop piece without generating a dog ear. A fork-like first gripping part is fixed to the distal end part of a rotating shaft being fixed to the rod of a first rotary cylinder. Then, the vicinities of both ends of the belt loop piece can be gripped under a pinched state by a pair of upper and lower forks which are formed on the first gripping part. In this case, a first movement-stopping member which approaches the belt loop piece gripped by the first gripping part from the upper side and keeps a contact state with the upper surface of the belt loop piece is provided, and a locking part is formed on the vertical part of the first movement-stopping member. Therefore, the side surfaces of the pinched belt loop piece are locked, and the movement-stopping state can be kept until the belt loop piece is delivered to a sewing machine.
DESCRIPTION OF THE INVENTION
The present invention aims to provide a device that relies on a suitable means for folding the belt loops to be applied on trousers or other items of clothing, the means comprising a further element for retaining the flap of folded-over material, thus creating a condition capable of eliminating or at least reducing the drawbacks highlighted above.
The invention aims in particular to provide a constructive solution that provides for the use of a mechanical device applied in the final part of the traditional arms of the folding system.
In order to contain the folded over flaps inside the belt loop, irrespective of the type of material and of the dimensions in width of the strip to be folded over, the mechanical device according to the invention comprises a third rotating pin that allows the material to be "combed" during its dedicated eccentric rotation, and a push to be maintained on the ends of material folded over inside the belt loop at the end of its rotation, whilst the material has been folded over by the rotation step of the other two pins present in each folding unit.
Another object of the invention is to provide a device for folding flaps of fabric that is simple and economical to produce and envisages the use of said third pin applied on a fixing point in its movement means, which is configured to allow the rotation thereof along its axis, and thus its initial position to be changed to compensate for the different types or thicknesses of material. ILLUSTRATION OF THE DRAWINGS
Additional features and advantages of the invention become apparent from the reading of the following description of one embodiment of the invention, provided by way of non-limiting example with the aid of the figures illustrated in the appended drawings, in which: figures 1 to Id represent schematic views showing solutions falling into the prior art; figure 2 illustrates a view regarding the solution according to the invention comprising the mechanical device formed by a third rotating pin associated with the fork-like pins; figures 3 and 4 represent schematic views of the device according to the invention with the belt loop placed between the folding members respectively in a first operating step and a second final operating step; figures 5 and 6 show schematic axonometric perspective views highlighting the details of one of the two folding units seen from two different angles; figures 7 and 1 are schematic front views highlighting, respectively, a first operating step of the third pin according to the invention and a second final step; figures 8 and 8' are detailed schematic front views highlighting, respectively, a first initial operating step of the third pin according to the invention and a second final operating step.
DESCRIPTION OF AN EMBODIMENT OF THE INVENTION
Making reference to the appended figures, and initially in particular to figures 2, 3 and 4, reference number 10 generally indicates a folding device according to the invention designed to fold two ends of material adapted for forming belt loops P.
Said device, according to one embodiment represented in the same figures, normally comprises a central device 11 provided with an arm 12, with an adjustable stroke, in order to keep the central part of the belt loop P locked in place.
The device 10 further comprises two pairs of fork like pins 13 and 14 parallel and rotating for each edge of material of the belt loop to be folded over, and which move so as to undergo axial rotations by means of respective rotating devices 15 and 16, each of which is driven by its own rotation device.
More in particular, making reference to one of the two pairs of fork-like pins, i.e. the one indicated by 14, it comprises a pin 14a, which in the rest position is positioned above the pin 14b, and both rotate about the axis of the pin 14b during the operating steps in order to be moved relative to the latter from a 12°'clock position to a 9°'clock position after a rotation of 210°.
According to an embodiment of the invention, a movement unit has been added to each pair of fork-like pins 13 and 14, said unit including a third pin 17, in this case an "S"-shaped pin rotating about the axis of the same pin 14b, disposed on an axis parallel to the rotation axis of the rotating device 16.
More in particular, according to the embodiment represented in figures 5 and 6, the pin 17, which consists of a metal rod with an off-axis median portion 17' that forms two portions with axes parallel to those of the pins 14a and 14b, is applied on the edge of an annular bush 18 that can rotate about its own shaft 19 which generates a rotation, driven by a rotary cylinder, that is transmitted to the rotating devices 15 and 16 on the axis of the pin 14b.
In even greater detail, according to the embodiment represented in figures 2 and 3 and even better in figures 4 and 5, the same annular bush 18 is provided with a pair of concentric arch-shaped slots 20 and 21 disposed radially as an arc of a circle and offset from each other.
Projecting from the first slot 20 there is a set screw
22 solidly joined to the shaft 19, whereas the second slot 21 is intercepted by a further fixed set screw 23 solidly joined to a locking plate 24 fixed onto the machine body by means of a screw 25.
The set screws 22 and 23 operate in the respective offset arch-shaped slots 20 and 21 so as to enable a controlled rotation of the pin 17 synchronised with the movements of the shaft 19, which in turn drives the rotation of the pins 14a and 14b.
In practical terms, the action of the set screws 22 and 23 develops into a reciprocal opposition thereof in the respective slots 20 and 21, with the result that the pin 17 can move angularly exactly in an eccentric manner in perfect synchronism and with maximum precision.
In other words, the action of the set screws 22 and
23 is such that the rotation of the shaft 19 imparts a main rotation both to the pin 14a that rotates about the axis of the pin 14b, and to the set screw 22 which operates inside the slot 20, and a secondary rotation of the annular bush 18 whose rotation begins when the set screw 22 has moved angularly until reaching the opposite end of the slot itself in opposition to the set screw 23, which acts as a limit stop in the slot 21.
From an operational point of view, the bush 18 consists of a ring that imparts to said pin 17, applied on the annular edge thereof, an eccentric rotation due to the rotation of the bush itself about the axis of the shaft 19 which moves the pin 17 from its starting point distal to the material to its final point proximal to the material in opposition to the set screw 23, which acts as a limit stop in the offset slot 21.
The total eccentric rotation allowed to the pin 17 is given by the rotation of the shaft 19 about the axis of the pin 14b (270 degrees) minus the length of the slot 20 formed on the bush 18.
In practical terms, when the set screw 22 arrives in contact with the end opposite the starting point in which it is positioned in the slot 20, it imparts a rotation to the annular bush 18 on which the pin 17 is inserted, in opposition to the set screw 23 acting as a limit stop.
It should be noted that the folding device according to the invention designed to fold two flaps of material adapted for forming belt loops P comprises two matching symmetrical folding units, each of which comprises a pair of fork-like pins 13 and 14 parallel and rotating for each edge of material of the belt loop to be folded over, which move so as to undergo axial rotations by means of respective rotating devices 15 and 16, each of which rotates in a direction opposite that of the other.
Summing up, the above-described device is made in such a way as to allow:
• a specific angle of rotation of the pin 17 relative to the rotation of the other two rotation pins 14a and 14b;
• a step of eccentric rotation of the pin 17 so as to change the starting point and the final point of arrival thereof relative to the belt loop to be folded; • a guide for maintaining the mechanical device in a longitudinal position relative to the axis of the rotation curve of the end of the belt loop to be folded, which coincides with the axis of the shaft 19 and of the pin 14b;
• the final part of the third rotating pin 17 to comb and at the end of its rotation maintain the upper profile of the material in the same position whilst the other two pins 14a and 14b are rotating the outer flap to the inside of the belt loop;
• the tension of the material to be compensated for, with force, by pushing the folded over edge inwardly;
• the different thicknesses in the point of the trousers where the belt loop is applied (example: yoke - crotch) to be compensated for with the elasticity of the material.
This device has the further advantage of being able to be included in a kit that can easily be applied to a standard folding system, so that it is possible to produce the belt loop P with "clean" flaps, as it were, thus reducing the costs and operations in the complete cycle of manufacture of the trousers, since the operation of cleaning after washing is eliminated.
Making reference to a sewing cycle that remains the same as that of the traditional folding device, which takes about 10 seconds to apply five belt loops on a pair of trousers, with the folding device according to the invention the step of cleaning after the inside edges of the five belt loops P have been washed, which normally takes a further 10 - 25 seconds per pair of trousers depending on the speed of the operator who performs the cleaning and the degree of automation applied to the latter operation, is removed. Consequently, using the device according to the invention, for every operator who applies the belt loop, one or two operators that clean the belt loops after washing are eliminated, as is the cutting unit necessary for each operator, with all the advantages deriving therefrom in terms of productivity and cost-effectiveness.
The invention has previously been described with reference to a preferred embodiment thereof. However, the possibility is envisaged of introducing some constructive variants that fall within the scope thereof, in the context of technical equivalence.