Separating device for flexible sheets

Abstract

The invention relates to the technical field of production lines or equipment for treating or processing flexible sheets. The preferred application of the invention is to manipulate animal leather subjected to tanning processing.

Description

[0001] manual

[0002] The present invention relates to the technical field of production lines or equipment for handling or processing flexible sheets.

[0003] A preferred application of the invention is the manipulation of animal hides that have undergone a tanning process.

[0004] It goes without saying that the invention can also be applied to the manipulation of any type of flexible sheet material, ie hide, synthetic leather, woven, non-woven, plastic sheets etc. and other types.

[0005] In the tanning process, and more generally in scenarios where large hides need to be manipulated, the problem of correctly loading the sheets into the handling and processing lines is of great concern. In fact, the sequential loading of the individual sheets must ensure that they are placed in an orderly manner and, above all, that the hide is fully stretched, without flaps, folds, wrinkles or irregularities throughout.

[0006] Precisely because of the complexity of this path, the steps requiring the placement of the leather according to a predefined arrangement associated with an operating unit for leather treatment are usually carried out in a predominantly manual manner.

[0007] The difficulties involved in placing the leather are in fact inherent in the type of material to be processed; by their very nature the various sheets of leather are of irregular size and shape and may be of varying thickness and of a non-homogeneous type.

[0008] Manual placement thus ensures a certain speed of manoeuvring and makes it possible for the operator to cope with the problems involving the variability of the supports from which the hides are taken and their placement (for technological reasons the hides may be stacked so that each one has a rough side in contact with the rough side of the hide below, which therefore places it in opposite directions and must therefore be placed correctly).

[0009] However, technology is indeed moving towards fully automated solutions, as the use of humans not only carries with it the inevitable uncertainties in accuracy and repeatability along the processing chain, but also involves the risk of potential physical hazards or risks to the health of the operators which cannot be ignored.

[0010] Devices have now been developed which make the handling and loading of even large and very irregularly shaped hides particularly reliable and which enable the efficient placement of flexible materials stretched out in a flat arrangement on surfaces of all types, both fixed and mobile.

[0011] While this device works, there is still the problem of properly presenting the sheet of flexible material at its opening.

[0012] In more detail, sheets of flexible material arrive at a working area arranged on various supports (e.g. air ducts, racks, hangers, pallets). For example, the sheets are stacked on top of each other on a support and across a central support; in this configuration, each sheet defines two flaps on either side of the support, which are arranged obliquely with respect to a plane perpendicular to the ground, forming a configuration similar to an inverted U. In order for a single sheet to be properly grasped by a handling device, it must be "detached", that is, one of its flaps must be lifted and then separated from the remaining stack of sheets below, so as to have at least one free edge accessible to the handling device.

[0013] The applicant points out that, in the knowledge of the prior art, this separation operation is still carried out manually, especially starting from the case of sheets stacked on a support. In fact, in this particular case, the placement of the sheets stacked in an inverted U shape on an inclined plane makes the operation of separating the individual sheets particularly complicated.

[0014] The Applicant therefore aimed to develop a device which solves this problem and automates the process of separating individual sheets of flexible material.

[0015] The purpose of the device according to the invention is therefore to operate a separation process in an automated, reproducible and industrializable manner.

[0016] Furthermore, the device according to the invention achieves the purpose of presenting the individual sheets to the handling device in the correct position for gripping according to the correct positioning, which provides conditions for full stretching of the animal hide without folded sheet sags, creases, wrinkles or irregularities as a whole.

[0017] Features and advantages of the separation device according to the invention will become more apparent from the following description of an embodiment thereof, given by way of non-limiting example with reference to the accompanying drawings, in which:

[0018] - Figure 1 shows a processing plant for sheets of flexible material, in which a stack of a plurality of sheets of this material stacked on top of each other and arranged on a support, a separation device and a workstation downstream of the separation device can be seen;

[0019] - Figure 2 The step of grabbing the sheet-like drooping object of the first sheet of the stacked plurality of sheets by the separation device is shown;

[0020] - Figure 3 The separating device in the step of lifting the sheet-like pendant is shown;

[0021] - Figure 4 A separate separation device is shown;

[0022] - Figure 5 is a view of the suction port used to grab the sheet-like pendant;

[0023] - Figure 6 Here’s another view of the mouthpiece (this time from above);

[0024] - Figure 7 A gripping member consisting of several suction nozzles is shown in separate and exploded views; and

[0025] - Figure 8 Detailed Description of the Invention The figure shows a separating device, in particular a gripping member.

[0026] With reference to said figures, consider a stack of sheets of flexible material stacked on top of each other on a support C. The support has a configuration with inclined sides, each defining a stacking plane AA, inclined at an angle α relative to a vertical plane YZ according to a Cartesian triple defined by a horizontal axis X, a vertical axis Y and a transverse axis Z, and the vertical plane YZ is orthogonal to a ground plane defined as XZ.

[0027] For the purposes of this specification, a first sheet of the stack defines a sheet-like tab L arranged according to a stacking plane AA.

[0028] The present invention relates in particular to a separation device for grabbing and lifting a device L for a sheet-like pendant, comprising at least:

[0029] - members 1 for grasping the sheet-like pendants L, arranged in a row along a suitable transverse axis Z' parallel to the transverse axis Z;

[0030] - means 2 for positioning the gripping means in a position facing the flap on plane AA so as to exert thereon a gripping force substantially perpendicular to said plane AA itself;

[0031] - Member 3 for lifting the flap and moving the gripping member so as to move it towards and / or away from the plane AA according to a direction BB perpendicular to the plane AA itself.

[0032] Specifically, the member 1 for grasping the sheet-like hanging objects comprises a beam 10 which supports a plurality of protruding suction ports 11 , each of which is used to apply vacuum pressure to the sheet-like hanging objects L, and thereby apply a corresponding lifting force thereto.

[0033] Preferably, but not limitingly, each suction opening 11 protrudes vertically from the beam 10 .

[0034] The beam is arranged along the axis Z' and the suction openings 11 are mounted thereon in an ordered manner. In the example illustrated in the figures, there is only one row of suction openings 11, but other embodiments are possible in which there are several rows of suction openings, each row having a variable number of suction openings 11.

[0035] More specifically, refer to Figure 5 and Figure 6 Each suction port 11 comprises a cylindrical tubular sleeve 110 transmitting negative pressure at the lower end on which a specific insert 111 is arranged, defining an engagement surface with the flap. Optionally, this insert is mounted to the beam with a spring-buffered retraction 112, compensating for any height differences. An additional pair of tension springs 113 introduces a further advantageous feature of adaptability and gripping effectiveness, ensuring compensation for differences in positioning of the plane AA.

[0036] Associated with each suction opening is a spacing element 114 which projects parallel to the sleeve 110 .

[0037] When the spacer 114 contacts the sheet flap, the insert is separated and, with the appropriate amount of vacuum, it is able to grab and separate the sheet flap from underneath it, thereby overcoming any electrostatic forces and overcoming the limitations presented by the suction cup or other vacuum system (which tends to lift several sheets at the same time when sheets of breathable material are present).

[0038] In a preferred form of the present invention, the plurality of suction ports all contact the flap L at the same time and apply the same vacuum pressure and thus the same lifting force. This enables the flap L to be grasped and moved more efficiently.

[0039] According to another aspect of the invention, there is at least one set of movable suction openings 12 on the beam itself according to the direction Z′. In a preferred embodiment, this at least one movable set 12 is placed at one end of the beam 10 .

[0040] For more details, refer to Figure 7 and Figure 8 , the suction group 12 is mounted on a support 120 slidably engaged on the beam. The support 120 is in turn connected to a piston (for example of the pneumatic type) which allows the support and therefore the suction group to move the desired length along Z'. The purpose of this system is to widen and stretch the flap L, avoiding wrinkles during retraction.

[0041] Variants of this solution may be envisaged, for example, without limitation, the movable mouthpiece comprises only one mouthpiece and / or the movable mouthpiece is moved by other movement members relative to the piston described above.

[0042] In the example described, the beam 10 is equipped with two movable groups 12, 12', the ends of which are placed in correspondence and straddling a fixed group of suction openings.

[0043] Depending on the specific tension and pulling requirements of the flexible sheet material, other placements of the at least one set of movable suction ports on the beam are conceivable, such as in a central position.

[0044] Furthermore, the beam 10 is cantilever-supported by the column 100 along the axis Z′.

[0045] This column is slidably supported on the aforementioned mobile member 3 , which comprises a linear guide 30 arranged along its own horizontal axis X′, which is perpendicular to the transverse axis Z′ of the beam 10 .

[0046] In an embodiment, the sliding movement of the column on the linear guide is controlled by a piston 31 .

[0047] Furthermore, in the illustrated embodiment, the linear guide 30 is connected to the base 4 in an inclined manner by means of the aforementioned guide member 2. This comprises at least one hinge 20 and a propulsion device 21 of the linear guide, such as but not limited to a piston, the hinge 20 defining a rotation axis Z" parallel to the Z axis. In a preferred embodiment, the number of hinges is two. By applying a propulsion action between the guide and the base, the guide is tilted relative to the ground plane XZ due to the hinge connection rotating around the axis Z". The inclination of the guide means the inclination of the entire structure consisting of the beam 10 and the column 100, and thus means the inclination of the suction port positioning. The angle β is the target working angle corresponding to the preferred position, in which the suction port is facing the flat plane AA of the sheet pendant and is parallel to the flat plane AA of the sheet pendant. The gripping member thereby applies a gripping force to the sheet pendant L, which is substantially perpendicular to the plane AA.

[0048] In the position corresponding to the angle β, the linear guide defines a movement direction BB which is substantially perpendicular to the plane AA.

[0049] Adjustments to the positioning of the beam 10 may be made at the start of the operation (and thus may serve as a preliminary set-up adjustment), or may even be made during the course of work.

[0050] In addition to the embodiment just described, other possible embodiments of the guide member can be envisaged. For example, there can be a solution in which the column is fixed and the beam is anchored thereon in rotation about its own axis Z'.

[0051] Turning now to the description of the operation of the device, Figures 1 to 3With the help of , the sheet-like droop L of the first sheet of the sheet stack stacked on the support is presented in plane AA. In order to be grasped by the sheet material handling device placed downstream of the separation device, the sheet-like droop L must be grasped and lifted; the handling device is not shown in the figure and can be of several known types.

[0052] The guide member assembly is driven to arrange the beam 10 supporting the suction port in the correct position relative to the plane AA. At this time, the beam is moved along the beam BB by the moving member, approaching the sheet-like pendant L. When the suction port 11 contacts the sheet-like pendant L or approaches the sheet-like pendant L, it is sucked and then grabbed. If necessary, by driving at least one group of moving groups 12, the sheet-like pendant can be stretched to meet specific processing requirements. Once the sheet-like pendant L is grasped, the moving member moves the beam away in the direction BB; this movement causes the lifting of the sheet-like pendant L, thereby causing it to be separated from the sheet below. Therefore, the sheet-like pendant thus lifted can be grabbed by the manipulation device downstream of the separation device.

[0053] Another object of the invention is a device for manipulating a sheet of flexible material, such as, in particular, natural or synthetic leather, comprising at least the following elements:

[0054] - a support C for stacking a plurality of sheets of said flexible material, having a configuration with inclined sides, each defining a stacking plane AA inclined at an angle α with respect to a vertical plane YZ according to a Cartesian triple defined by a horizontal axis X, a vertical axis Y and a transverse axis Z and the vertical plane YZ being orthogonal to a ground plane defined as XZ;

[0055] - a first sheet of said stack defining a sheet-like drop L arranged according to said stacking plane AA;

[0056] -Control equipment,

[0057] is arranged downstream of the support C; and

[0058] equipped to contact the lifted sheet-like droop L and then move the first sheet toward the workstation 5;

[0059] - said workstation 5, which is located downstream of said manipulation device; and

[0060] - separation device,

[0061] A separation device operably disposed between the support C and the handling device, such as described above; and

[0062] Suitable for grabbing and subsequently lifting flaps.

[0063] The separating device according to the invention achieves several advantages. In particular, it allows the automatic gripping and lifting of the sheet-like sag of the first sheet of a stack stacked on a support, thus achieving the goal of eliminating operator use and thus manual intervention.

[0064] It was found that plants provided with the device meet the speed and precision requirements in the transport, transfer and processing of sheet materials.

[0065] In particular, the use of the separation device in leather processing lines in the tanning industry solves the problems of the prior art mentioned above; in fact, it is particularly effective in separating natural or synthetic leather arranged on a support, since it avoids manual intervention and also allows for quick, precise and reproducible grasping of leather sheets directly on the inclined leather arrangement plane. This facilitates the subsequent manipulation of the leather and its correct placement in the entire processing flow, significantly improving the overall quality of the process itself, while significantly reducing time.

[0066] The invention has been described with reference to its preferred embodiments. It is intended that there may be other embodiments related to the core of the invention, all of which fall within the scope of protection of the claims presented below.

Claims

1. A device for grasping and lifting a flap of a sheet of flexible material in a stack of a plurality of sheets of flexible material arranged one above the other, wherein the flap is arranged on a stacking plane AA, the stacking plane AA being inclined at an angle α relative to a vertical YZ plane according to a Cartesian triple defined by a horizontal axis (X), a vertical axis (Y) and a transverse axis (Z), and the vertical YZ plane being orthogonal to a ground plane defined as XZ, the device comprising: - means for grasping said flaps, arranged in a row along a suitable transverse axis (Z') parallel to said transverse axis (Z); - means for positioning said gripping member, suitable for arranging said gripping member in a position facing said flap on said plane AA so as to exert on said edge a gripping force oriented substantially perpendicularly to said plane AA; - a movement member for moving said gripping member towards and / or away from said plane AA in a direction BB substantially perpendicular to said plane AA, as a result of which movement said flap is lifted.

2. The device according to claim 1, wherein the gripping member comprises a plurality of suction ports (11), each suction port (11) applying vacuum pressure to the sheet-like hanging object (L) and thereby applying a corresponding lifting force thereto.

3. Device according to claim 2, wherein said plurality of suction openings protrude from a beam (10), said beam (10) being arranged according to said suitable transverse axis (Z'), each suction opening defining an engagement surface with said flap (L).

4. A device according to claim 3, wherein the mobile member includes a linear guide (30), the beam (10) is operably associated with the linear guide (30) in a sliding manner, and the linear guide is arranged according to a self-horizontal axis (X'), which is perpendicular to the self-transverse axis (Z') of the beam.

5. A device according to claim 4, wherein the fixed point member (2) includes at least one hinge (20) defining a rotation axis (Z") parallel to the axis (Z) and a pushing device (21) of the linear guide to obtain a rotation of the linear guide between an angle 0 at which the guide is arranged parallel to the horizontal plane XZ and an angle β at which the guide is operably arranged according to the movement direction BB.

6. A device according to any one of claims 2 to 5, wherein each suction port (11) comprises a cylindrical tubular sleeve (110), which transmits negative pressure at the lower end, and an insert (111) is arranged on the lower end, and the insert defines the engagement surface with the sheet-like pendant.

7. The device according to claim 6, wherein the insert is mounted on the beam with a spring-cushioned retraction arrangement (112).

8. Device according to claim 7, wherein at least one of said groups (12) of suction openings is slidable on said beam.

9. The device according to claim 8, wherein the groups (12) are arranged corresponding to the ends of the beam.

10. Device according to claim 8 or 9, wherein said at least one group (12) of said suction openings is mounted on a support (120) slidably engaged on said beam (10), said support (120) in turn being connected to a piston which moves said support a desired length along said beam.

11. A method for grasping and lifting a flap of a sheet of flexible material in a stack of multiple sheets of flexible material arranged one above the other, wherein the flap is arranged on a stacking plane AA, the stacking plane AA being inclined at an angle α relative to a vertical plane YZ according to a Cartesian ternary system defined by a horizontal axis (X), a vertical axis (Y) and a transverse axis (Z), and the vertical plane YZ being orthogonal to a ground plane defined as XZ, the method comprising the following steps: - orienting means for grasping said flaps, arranged in a row along a suitable transverse axis (Z') parallel to said transverse axis (Z), to a position facing said flaps on said plane AA; - moving said gripping member close to said plane AA according to a direction BB substantially perpendicular to said plane AA; - applying a gripping force to the flap that is oriented substantially perpendicularly to the plane AA itself; - moving the gripping member in the direction BB away from the plane AA to lift the flap.

12. A method according to claim 11, wherein the grasping member includes a plurality of suction ports (11), each suction port (11) applies vacuum pressure to the sheet-like hanging object (L) and thereby applies a corresponding lifting force thereto, wherein the plurality of suction ports protrude from a beam (10), and the beam (10) is arranged according to the appropriate transverse axis (Z'), whereby the beam moves along the direction BB to approach the sheet-like hanging object (L), so that the plurality of suction ports (11) can suck and thereby grasp the sheet-like hanging object through the vacuum pressure applied by the suction ports (11).

13. Apparatus for separating sheets of flexible material, such as natural or synthetic leather, comprising at least the following elements: - a support (C) for stacking a plurality of said sheets of flexible material, having a configuration with inclined sides, each defining a stacking plane (AA), said stacking plane (AA) being inclined at an angle α with respect to a vertical plane (YZ) according to a Cartesian triple defined by a horizontal axis X, a vertical axis Y and a transverse axis Z and said vertical plane (YZ) being orthogonal to a ground plane defined as (XZ); - a first sheet of said stack defining a sheet-like drop L arranged according to said stacking plane AA; -Control equipment, arranged downstream of the support; and equipped to contact the lifted sheet-like droop (L) and subsequently move the first sheet material toward the workstation; - the workstation, which is located downstream of the manipulation device; and - a device, such as the one according to claims 1 to 10, suitable for grasping and subsequently lifting the flap, wherein the device is operatively arranged between the support and the manipulation device.

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