IMPROVED LINEAR TURNING-IN/FOLDING MACHINE

This invention relates to an improved linear turning-in/folding machine. More particularly, this invention relates to an improved linear turning-in machine, typically for processing semi-finished leather goods.

The use of traditional turning-in or folding machines is known in the production of leather goods such as wallets, purses, bags and all products that comprise pockets. Said machines are suitable to automatically perform turning-in or folding along an upper edge of a strip of material, generally leather, which is coupled to a fabric part for forming walls and divider partitions of pockets and slots suitable to contain identification cards, credit cards, documents and the like.

Each pocket, or part of it, is made with a portion of fabric (natural or synthetic) coated in whole or in part on the visible outer by a portion of leather that is then turned-in or folded on itself, along the upper edge of the fabric portion, and glued on the opposite inner face after turning-in or folding. Adhesive materials are used to stabilise the flap of the folded leather portion and said flap is further pressed between two plates, at least one of which is heated, in order to favour complete bonding.

These operational processing steps are generally performed on known linear turning-in machines, which also perform a so-called grooving on the edge of pockets intended for articles of particular value, an operation that was traditionally performed manually by experienced operators. Said grooving operation consists in creating an extended longitudinal projection in correspondence of the upper edge of the pocket, along the flap of folded leather, which is obtained during the compression of the cited plates; one of these plates, generally the lower one, is provided with a projection defined tooth, which creates the above-mentioned grooves on the surface of the leather.

A typical example of these known machines is described in Italian patent No. IT 276755 (Y1), in the name of the same applicant, and which claims a turning-in machine for processing semi-finished leather goods comprising a frame, a tilting presser, a front surface for the support and positioning of elements by turning-in, on which said tilting presser acts activated by a pneumatic cylinder and a lower fixed plate cooperating with a movable plate combined with means suitable for its movement in the vertical direction and for its horizontal translation in the direction of the same front support surface. The movable plate is superimposed on the lower fixed plate in such a way as to perform the cold or hot pressing of each element to be turned-in, after previously being provided with a layer adhesive. The front part of said machine integrating the front support surface can be moved away from the rear part that comprises said tilting presser, the fixed lower plate and the movable plate, in order to allow easy access to the plates themselves during cleaning.

However, said known turning-in machines have significant limitations and drawbacks, such as to not allow the same automatic processing of fine leather goods to match the precision and the quality of manual processing.

A typical drawback of these known turning-in machines is due to the fact that, during the step of turning-in the leather portion, the latter is fully in contact, along its entire exposed surface, with the heated bottom plate. Therefore, said plate fully transfers the heat on the entire outer surface of the leather, including that not involved in the turning-in or gluing, thus creating defects and imperfections such as dilatations and shiny parts on the leather, especially on materials having a reduced thickness, and such as to affect the quality of workmanship. Excessive heating can also cause defects on materials with special decorations and finishes.

A further drawback of the known turning-in machines regards the coplanarity between the movable plate and fixed plate, necessary for achieving a homogeneous pressing along the entire folded surface. It often happens that a homogeneous pressing is not achievable because the thickness of the material is variable, especially in fine leather. Since the movable pressing plate is hinged at a fixed point, it follows that the incidence of the same plate is inhomogeneous, as the thickness of the material varies, with respect to a standard height, with the consequence that the pressing of the elements is equally inhomogeneous and the final gluing of the parts is not optimal. Additionally disadvantageous is the fact that a non-homogeneous pressing of the parts does not allow the realisation of a complete and uniform grooving. Since the material, generally leather, is of variable thickness, and the incidence of the movable plate itself varies with the thickness, it follows that the scoring of the material, obtained by said movable plate in cooperation with the tooth or projection disposed on the lower plate, is not optimal and homogeneous. This leads to incomplete and discontinuous grooving, such as to not allow automatic processing to achieve the levels of quality of manual processing. The purpose of this invention is to overcome the drawbacks listed above.

More particularly, the purpose of this invention is to provide an improved linear turning-in/folding machine suitable to allow, in an automatic way, the performance of turning-in/folding, gluing and grooving operations with a precision and quality of workmanship such as to equal the manual operations. A further purpose is to provide an improved linear turning-in/folding that allows heating of the surface of the material localised to the portion of the surface suitable to be glued.

A further purpose of the invention is to provide an improved linear turning-in/folding machine suitable to allow, on materials of variable thickness, a homogeneous pressing along the entire surface of the material to be turned-in. A further purpose of the invention is to provide an improved linear turning-in/folding machine suitable to allow, on materials of variable thickness, a homogeneous grooving along the entire surface of the turned-in material.

A still further purpose of the invention is to make available to users technical improvements to turning-in/folding machines, such as to be easily and economically integrated on existing machines.

A still further purpose of the invention is to make available to users a turning-in machine suitable to ensure a high level of strength and reliability over time, such as to be easily and economically constructed.

These and still other purposes are achieved by the improved linear turning-in/folding machine of this invention according to the main claim.

The constructive and functional characteristics of the improved linear turning-in/folding machine of this invention will be better understood from the detailed description that follows, in which reference is made to the accompanying drawings that illustrate a preferred, and not limiting, embodiment and in which:

• Figure 1 is a schematic, axonometric and partially sectioned representation of an improved linear turning-in/folding machine of this invention;
• Figure 2 is a schematic, axonometric and partially sectioned representation of the processing unit of an improved linear turning-in/folding machine of this invention;
• Figure 3a is a schematic representation of a sectional view of the processing unit of an improved linear turning-in/folding machine of this invention;
• Figure 3b is a schematic representation in detail of the work area between the plates of the sectional view of Figure 3a;
• Figure 4 is a schematic representation of a plan view of the processing unit of an improved linear turning-in/folding machine of this invention.

With initial reference to Figures 1 and 2, the improved linear turning-in/folding machine of this invention is indicated in its entirety by 10, comprises a support structure 12, provided with known means of control and command of the turning-in/folding machine 10 itself, known means for connection to electrical and pneumatic power and includes a processing unit 14 suitable to perform turning-in operations on semi-finished elements and provided with known, pneumatic cylinder type, movement means. With particular reference also to Figures 3a, 3b and 4, said processing unit 14 includes a front part 16 with a support surface 18 for the positioning of the elements to be turned-in, a tilting presser 20 suitable to lock a semi-finished element by means of a first profile 22 stabilised to the same presser 20 and a second profile 22' activated by an actuator 24, generally comprising a known linear pneumatic cylinder. Always with particular reference to Figures 3a, 3b and 4, said processing unit 14 comprises a first fixed plate 26 made of metal, provided with known heating means such as electric resistors and the like, cooperating with a second movable plate 28, preferably made of metal, in combination with movement means 50 of the same in the vertical direction and for its horizontal translation in the direction of said support surface 18. Said second movable plate 28 is also advantageously provided, for certain types of processing, with known heating means of the type of electric resistances and the like. Said first fixed plate 26 and said second movable plate 28, known in themselves, are able to cooperate by means of superimposition of said second movable plate 28 on said first fixed plate 26. The first fixed plate 26 is stabilised to said processing unit 14 by means of known fixing means, generally screws, shaped swallow-tail or T grooves, joints and the like. The second movable plate 28 is slidably stabilised to said movement means 50 and is slidably removable laterally with respect to the same processing unit 14 in order to be removed. Said first fixed plate 26 is disposed in correspondence of, and in coplanarity with, the most forward part of the support surface 18 on which is disposed the semi-finished element to be turned-in. With particular reference to Figure 3b, said first fixed plate 26 is provided with a projection 26', formed on its surface exposed and substantially along its entire length, having a cusp-shaped section, generally triangular, and suitable to act to mark the surface of the semi-finished product to be processed.

With reference again to Figures 1 to 4, said processing unit 14 also comprises at least one pair of adjustments 30,30', known in themselves, and suitable to regulate the vertical and horizontal stroke of the second movable plate 28.

The front part 16 of the processing unit 14, provided with the support surface 18, can be advantageously moved away from the rest of the processing unit 14 comprising the presser 20, the first fixed plate 26 and the second movable plate 28, said front part being hinged below said processing unit 14; this in order to be able to easily perform operations of disassembling the parts for cleaning and maintenance.

With reference again to Figures 1 to 4, and in particular to Figures 3a and 3b, the turning-in/folding machine 10 has an innovative processing unit 14, with a first fixed plate 26 that comprises an insulating portion 40 arranged and stabilised in a housing formed on the exposed surface of said first fixed plate 26, in such a way that the exposed surface of said insulating portion 40 is coplanar and contiguous to the exposed surface of said first fixed plate 26. The insulating portion 40 is advantageously extended on the entire exposed surface of said first fixed plate 26, from the outer end arranged towards the support surface 18 up to the vicinity of said projection 26' and substantially along the whole length of the first fixed plate 26. Said insulating portion 40 is made of heat-insulating material, such as polymeric plastic materials, refractory materials, wood or similar and suitable to not allow or, in any case, considerably reduce the transmission of heat from the first fixed plate 26 to the semi-finished element to be turned-in, said insulating portion 40 being stabilised to the same first fixed plate 26 with known fixing means such screws, joints, gluing and the like.

With reference to the same figures, the same processing unit 14 is further provided with a second movable plate 28 of innovative type, comprising a deformable portion 42, resilient and made of elastic material and advantageously deformable such as elastomeric plastic material, vulcanised rubber and similar, arranged and stabilised with known fixing means, screws, joints and gluing and preferably extended over the entire lower surface and substantially the entire length of said second movable plate 28.

A further innovative characteristic of the improved linear turning-in/folding machine 10 is that of comprising, as stabilisation means of the second movable plate 28 with the deformable portion 42, magnetic elements 44, generally of cylindrical shape, made of ferromagnetic material, preferably neodymium magnets or samarium cobalt magnets that allow having elements of small sizes with high magnetic forces and high resistance to temperature and corrosion. Said magnetic elements 44 are slidably disposed in corresponding slots and suitably stabilised to the movement means 50 of the second movable plate 28, said means generally comprising a metal bar suitable to house said second movable plate 28, said magnetic elements 44 being placed in contact with the upper surface of the same second movable plate 28 opposite to the surface suitable to be pressed. Said magnetic elements 44, when activated by a related activation, keep the second movable plate 28 stable in working position, while, when the same magnetic elements 44 are deactivated, the same second movable plate 28 is free to slide with respect to the bar of the movement means 50 and be slid off laterally with respect to the processing unit 14 by means of a tool 60, suitable to be hooked to the same second movable plate 28 by means of suitable hooking holes formed on the end of it.

From the description of the constituent parts of the improved linear turning-in/folding machine of the invention, one can infer its operation, described below.

With reference to Figures 1 to 4, the turning-in/folding machine 10 of this invention works in the same way as a traditional turning-in machine of the prior art.

The semi-finished element (not shown) is generally composed of a base element superimposed and pre-glued to a leather element to be turned-in and previously treated with adhesive material on the surface to be turned-in. Said semi-finished element is positioned by the operator, using known references, on the support surface 18 in such a way as to bring the flap of the leather element to be folded in correspondence of the second movable plate 28. The semi-finished element, thus properly arranged, is stabilised in position by means of the activation of the presser 20 which presses the same semi-finished element against the exposed surface of the first fixed plate 26, in correspondence of the surface portion not subject to turning-in. The known combination of linear vertical and horizontal movements of the second movable plate 28 of the processing unit 14 performs the operation of turning-in/folding the flap of the leather element on the base leather element up to pressing the turned-in flap, by mean of the deformable portion 42 of the second movable plate 28, on the first fixed plate 26. The first fixed plate 26, heated by means of known electrical resistances, allows a proper and effective adhesion and cohesion of the adhesive material with the flap of the leather element to be folded and with the base element. As is apparent in particular from Figure 3b, the metal part of the first fixed plate 26 advantageously transmits heat only in the part of the exposed surface of the first fixed plate 26 placed in the vicinity of the projection 26', while in the remaining part of the surface the heat is not transmitted, or is transmitted in limited quantity, thanks to the insulating portion 40 which prevents the heat from affecting the remaining surface part of the semi-finished element not subject to the operation of turning-in/folding, thus avoiding damage to the semi-finished element itself, particularly to the leather element that, with heat, is subject to more or less extensive deformations and to the formation of shiny parts in correspondence of the areas of contact and heat transfer.

Finally, the folded flap of the semi-finished element is advantageously pressed against the first fixed plate 26, in the part heated and provided with the projection 26', by the second movable plate 28 by means of its deformable portion 42. Said deformable portion 42 of the second movable plate 28 allows a uniform pressing of the turned-in flap of the element, since it allows the same second movable plate to yield in the surface portion in contact with the projection 26' avoiding jamming due to the presence of the same projection and a not perfect coplanarity of the second movable plate 28 with the first fixed plate 26. This technical solution ensures a proper and uniform pressing of the turned-in flap and a proper and uniform performance of the grooving, obtained by marking the leather in the vicinity of the folded edge by means of the projection 26', on leather elements of significantly variable thickness as in the case natural leather, thus allowing the automatic performance of quality workmanship normally obtainable only by manual workmanship.

The second movable plate 28 is used for the types of processing that do not require the heating of the movable plate since its deformable portion 42, generally made of elastomeric and insulating material, makes it unsuitable to be heated. The same second movable plate 28 is advantageously and quickly replaceable with a traditional second movable plate by demagnetising the magnetic elements 44, through an activation, and sliding off the same second movable plate 28 laterally to the processing unit 14 using the tool 60 and without the need to act on the locking screws.

As can be seen from the foregoing, the advantages achieved by this invention are clear. The improved linear turning-in/folding machine of this invention is particularly advantageous because it allows automatically performing, and with increased productivity, the operations of turning-in/folding, grooving and gluing flaps of fine semi-finished elements having a precision and quality of workmanship equal to manual workmanship.

A further advantage of this invention is that of providing the user an improved linear turning-in/folding machine that allows the heating of the surface of the leather element exclusively in the area involved, avoiding damaging the leather with the heat and avoiding dilation and parts and shiny parts.

A further advantage of this invention is that of allowing an automatic compress and uniform and homogeneous gluing on fine materials and natural leathers along the entire surface of the material to be turned-in.

Further advantageously for this invention is the fact of facilitating and speeding up the operations of replacing and disassembling the machine and allowing a rapid and economic integration and interchangeability of parts with existing machines.

Although the invention has been described with particular reference to a preferred embodiment, provided only by way of non-limiting example, many modifications and variations will be apparent to a person skilled in the art in light of the above description. Therefore, this invention intends to embrace all the modifications and variants falling within the spirit and scope of the following claims.