Multi-functional Work Centre for Cutting and Machining Plates of Stone, Marble, or, in General, Natural or Synthetic Stone Material, or Ceramic Material

Abstract

A numeric-control work centre can be used for carrying out cutting operations or grinding and/or milling operations on plates of stone, marble, or, in general, natural or synthetic stone material, or ceramic material. The work centre comprises at least one working head movable along at least two mutually orthogonal horizontal axes on a work surface. The work surface includes a rigid supporting board, which defines a first planar supporting surface, and a series of sacrificial elements rigidly connected to the rigid supporting board. The sacrificial elements are arranged in positions spaced apart from each other and define a second supporting surface located at a higher level than the first planar supporting surface, so that a cutting tool coupled to the working head engraves the sacrificial elements, without interfering with the supporting board during a cutting operation on a plate resting on the sacrificial elements, whichever is the path followed by the cutting tool. Between the sacrificial elements there remain free portions of the planar surface of the supporting board, so that they can be removably engaged by one or more blocks for supporting and holding the plate. These blocks project above the sacrificial elements and are adapted to define a third supporting surface, located at a higher level than the second supporting surface, for supporting and holding a plate during a milling or grinding operation on the plate.

Claims

1. A numeric-control work centre for machining plates of stone, marble, or, in general, natural or synthetic stone material, or ceramic material, said work centre comprising: a work surface; at least one working head movable on the work surface in at least two mutually orthogonal horizontal directions, wherein said working head can be selectively coupled either to a grinding or milling machining tool for performing grinding or milling machining operation on a plate or to a cutting tool for a cutting operation the plate, wherein said work surface includes: a rigid supporting board, defining a first planar supporting surface; and a series of elements for supporting said plate during said cutting operation, said elements being rigidly connected to said rigid supporting board and defining a second supporting surface located at a higher level than said first planar supporting surface of said supporting board, so that said cutting tool coupled to said at least one working head can carry out said cutting operation on said plate arranged on said elements for supporting the plate, without interfering with the supporting board; and, a third supporting surface located at a higher level than said second supporting surface, and adapted for supporting and holding said plate during said grinding or milling machnining operation performed on the plate by said grinding or milling machining tool coupled to said working head and suitable for performing said grinding or milling machining operations on the plate, and further wherein, said series of elements for supporting the plate during said cutting operation are rigid sacrificial elements secured to the work surface and made of a sacrificial material such that said cutting tool used in the cutting operation can pass through the plate and also engrave the sacrificial elements, without interfering with the work surface, so that the cutting tool can be guided according to any path on the work surface, without being forced to avoid interference with said sacrificial elements, said third supporting surface comprises a plurality of supporting blocks, each supporting block having a bottom suction cup that can be selectively activated for adhering to said work surface and a top suction cup that can be selectively activated for holding thereon said plate to be subjected to said grinding or milling machining operation; wherein defined between the sacrificial elements are free portions of said first planar surface of the supporting board, which are confined between said sacrificial elements and distributed throughout an entire extension of said first supporting surface, so that they can be used for removably engaging said supporting blocks thereon; and in at condition where said supporting blocks are engaged on respective free portions of the work surface, the top suction cups of the supporting blocks project above said sacrificial elements and define said third supporting surface.

2. The work centre according to claim 1, wherein said rigid supporting board is integrated in a bench of said work centre.

3. The work centre according to claim 1, wherein said sacrificial elements comprise slats secured atop said supporting board and arranged so as to form at least one array of slats spaced apart from one another by a distance greater than a horizontal dimension of said supporting blocks.

4. The work centre according to claim 3, wherein the at least one array of slats comprises two arrays of parallel slats arranged spaced apart from each other, along two different directions.

5. The work centre according to claim 1, further comprising: a bench supporting said work surface; two stationary side portions arranged at opposing two sides of the bench; an overhead cross-member movably supported above the two side portions in a horizontal direction orthogonal to a horizontal direction of the cross-member, in a gantry-like fashion; and a carriage movable on the cross-member in said horizontal direction of the cross-member, said at least one working head being carried by the carriage and being movable with respect thereto in a vertical direction.

6. A method for performing a cutting and machining cycle on a plate made of natural or synthetic stone material, or ceramic material, by a work centre according to claim 1, the method comprising: a cutting tool is associated to a working head of the work centre; a plate to be cut is arranged on said second supporting surface defined by said sacrificial elements; said working head is controlled so as to carry out a cutting operation on said plate; respective supporting blocks are arranged on said free portions of the first supporting surface, selecting the positions of said blocks according to the shape and dimensions of the plate; said plate is positioned on said third supporting surface defined by said supporting blocks; a grinding or milling machining tool is associated to the working head; and said working head is controlled so as to carry out a grinding or milling machining cycle on said plate.

7. A work center for use in cutting and machining of plate material, the work center comprising: a work surface having a rigid supporting board, the rigid supporting board defining a first supporting surface; a plurality of sacrificial elements connected to the rigid supporting board, each sacrificial element positioned a horizontal distance from an adjacent sacrificial element, the plurlaity of sacrificial elements defining a second supporting surface elevated above the first supporting surface, the second supporting surface selectively operable to support the plate material during a cutting operation, wherein the plate material can be through cut without cutting the rigid supporting board; a third supporting surface supported by the first supporting surface and elevated above the second supporting surface, the third supporting surface selectively operable to support the plate material during a machining operation; and a working head movable relative to the work surface, the working head operable to selectively cut or machine the plate material positioned on one of the respective second or the third supporting surfaces.

8. The work center of claim 7 wherein the third supporting surface comprises: a plurality of supporting blocks selectively positioned on the first supporting surface, each of the plurality of supporting blocks comprising: a lower suction cup selectively engageable with the first support surface; an upper suction cup defining the third supporting surface selectively engageable with the plate material to prevent movement of the plate material relative to the work surface; and a peripheral horizontal width.

9. The work center of claim 8 wherein the plurality of sacrificial elements further comprise: a first array of slats wherein the horizontal distance between adjacent slats is at least as large as the supporting blocks peripheral horizontal width such that one of the plurality of supporting blocks can be positioned between adjacent slats.

10. The work center of claim 9 wherein the plurality of sacrificial elements comprises: the first array of slats; and a second array of slats angularly positioned offset from the first array of slats, the second array of slats having the horizontal distance between adjacent second second array slats at least as large as the supporting blocks peripheral horiziontal width such that one of the plurality of support blocks can be positioned between adjacent second array of slats.

11. The work center of claim 7 further comprising: a bench supporting the work surface; a cross member connected to the bench, the cross member selectively movable in a Y coordinate direction relative to the work surface; and a carriage connected to the cross member, the carriage selectively movable in a X coordinate direction relative to the cross member; a slide structure connected to the carriage and the working head, the slide structure selectively movable in a Z coordinate direction relative to the carriage, the cross member, carriage and slide structure operable to selectively position the working head in the X, Y and Z coordinate dimensions relative to the work surface.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Further characteristics and advantages of the invention will appear from the following description with reference to the annexed drawings, which are provided purely by way of non-limiting example and in which:

[0030] FIG. 1 is a front perspective view of an examplary embodiment of a work centre according to the invention, illustrated during execution of an cutting operation on a plate arranged on the sacrificial supporting surface of the work centre;

[0031] FIG. 2 shows the same work centre as that of FIG. 1 during execution of a grinding operation on the peripheral lateral surface of a plate, where the plate is held on suction-cup supporting blocks, which are arranged on the supporting board of the work centre, in free portions of the surface of the board that are confined between elements of the sacrificial supporting surface; and

[0032] FIGS. 3 and 4 are a cross-sectional perspective view and a cross-sectional view of a detail of the supporting board forming part of the work centre according to the invention, FIG. 4 also illustrating a plate positioned on the sacrificial supporting surface and a plate positioned on suction-cup supporting blocks that engage on the surface of the supporting board.

DETAILED DESCRIPTION

[0033] In FIGS. 1 and 2, the reference number 1 generally designates a numeric-control work centre according to the present invention. The work centre 1 comprises, in a way known per se, a stationary structure including a bench 2 defining a work surface generally designated by 3. On two opposite sides of the bench 2, the stationary structure of the machine includes a pair of side portions 4. The work centre 1 comprises one or more working heads H (in the illustrated example, a single working head H is provided) which, once again in a way known per se, is supported by a slide structure 6 that is movable in a vertical direction Z on a carriage 7. Once again according to the conventional technique, the carriage 7 is slidably mounted in the longitudinal direction X of a cross-member 8 that is movably mounted, in a gantry-like fashion, above the two side portions 4 in a horizontal direction Y orthogonal to the direction X. The movement of the carriage 7 along the cross-member 8 in the direction X, the movement of the cross-member 8 in the horizontal direction Y, and the movement of the slide 6 in the vertical direction Z are controlled by respective electric motors (not illustrated) controlled by an electronic control unit (not illustrated) according to any predetermined machining program.

[0034] The constructional details of all the components described above of the work centre are not illustrated herein since they can be made in any known way and do not fall, taken alone, within the scope of the present invention. Moreover, the deletion of these constructional details from the drawings renders the latter more readily and easily understandable.

[0035] Once again according to the conventional technique, the working head H is provided with a motor-driven spindle (not visible in the drawings) to which a working tool can be removably coupled.

[0036] Normally, in work centres of the type described herein, the working head can be coupled to a grinding tool or a milling tool, to carry out, for example, milling operations to obtain recesses or openings in the plate, or grinding operations to machine the peripheral lateral surface of the plate and the edge of one or more openings formed within the perimeter of the plate (when these are provided) or to carry out any other type of machining operation. In the case of the work centre according to the invention, the working head can also be coupled to a tool for cutting the plate, the tool being typically in the form of a diamond disk blade, designated by D in FIG. 1.

[0037] The exemplary embodiment illustrated herein has a single working head H. In this case, the working head H is designed to operate both with a cutting tool and with a grinding or milling tool. The work centre 1 is provided with a tool magazine (not visible in the drawings) on a side of the bench 2, where the working head can be positioned to carry out automatically a tool-change operation. However, the work centre according to the invention could also be provided with a number of working heads, in which case each working head can be dedicated just to cutting operations or just to milling and grinding operations, or else each of the working heads can be provided for carrying out both types of operations.

[0038] The work centre 1 is provided with a work surface 3 defined by a supporting board 10 (see FIGS. 3 and 4), the structure of which will be illustrated hereinafter. Purely by way of example, the supporting board 10 is illustrated in FIG. 3 as constituted by a plurality of modular elements 101 in the form of metal sectional elements, which are set alongside one another and define with their top surfaces a first planar and continuous supporting surface 11. Once again with reference to the specific example illustrated in FIG. 3, the metal sectional elements 101 have longitudinal sides with complementary sectional elements in such a way that these metal sectional elements 101 are slotted together and moreover define a plurality of longitudinal slots 102. Received and fixed by means of screws 12 (see FIG. 4) within the longitudinal slots 102 are a plurality of slats of wood 131, which are thus parallel to one another and set at a distance apart, constituting a first array of slats of a sacrificial supporting surface 13 carried by the supporting board 10. In the example illustrated, the slats 131 of the first array are directed parallel to the direction X of the machine. As may be seen in FIG. 3, the top surfaces of the metal sectional elements 101 that define the first supporting surface 11 also have transverse slots, received and blocked within which, for example, by means of screws, are portions of slats of wood 132 arranged orthogonal to the slats 131 of the first array. The portions of slats 132 define a second array of slats set parallel to one another and at a distance apart, orthogonal to the slats 131 of the first array. Both the slats 131 and the portions of slats 132 project above the first supporting surface 11 to define a second supporting surface 14, located at a higher level than the first supporting surface 11.

[0039] Of course, the supporting board 10 can have a structure of any type, the specific configuration described above here being provided purely by way of example. In particular, the material of the slats may be any other sacrificial material alternative to wood. The slats could also be arranged in two different, but not orthogonal, directions. In the work centre according to the invention, the plate to be worked is set resting on the second supporting plane 14 defined by the sacrificial supporting surface 13 that is constituted by the slats of wood 131, 132, when it is necessary to carry out a cutting operation, as illustrated in FIG. 1.

[0040] Once positioned on the sacrificial supporting surface 13 constituted by the slats of wood 131, 132, the plate remains stationary by gravity during the cutting operation, thanks also to the friction between the bottom surface of the plate and the surface of the slats of wood 131, 132.

[0041] During the cutting operation, the disk blade D traverses the plate L positioned on the sacrificial supporting surface 13 throughout the thickness of the plate and projects for a few tenths of millimeter underneath the plate L. In this way, the disk blade D can engrave the slats 131, 132 that it possibly finds along its path, without however interfering with the supporting surface 11 of the supporting board 10.

[0042] Once again with reference to the specific example illustrated, the sacrificial supporting surface 13 also includes one or more perimetral slats of wood 133 fixed to the periphery of the supporting board 10 by means of screws 15.

[0043] It is important for the structure of the sacrificial supporting surface 13 to be made up of sacrificial elements, such as the slats of wood 131, 132 arranged at a distance apart in such a way as to leave free wide portions of the aforesaid first supporting surface 11 (designated by 110 in FIGS. 2 and 3), confined between the sacrificial elements, which are designed to be removably engaged by blocks V (see FIGS. 2 and 3) for supporting and withholding the plate, which project above the sacrificial elements 131, 132 so as to define a third supporting surface 16 (see FIG. 4) located at a higher level than the second supporting surface 14 defined by the sacrificial supporting surface 13, for supporting and holding a plate L during a grinding or milling operation on the plate (FIG. 2).

[0044] With reference to FIG. 4 (where the modular elements 101 are illustrated only schematically), the blocks V are of the known type including a bottom suction cup V1, a top suction cup V2, and connectors V3, V4 for connecting the suction cups to a source of vacuum provided within the stationary structure of the machine. For this purpose, once again according to the conventional technique, the connectors V3, V4 are connected to the ends of hoses F, which are in turn connected to connectors R provided on the stationary structure of the machine. The present description of the supporting and holding blocks V is provided herein purely by way of example. Alternatively, these blocks may be made in accordance with a known technique developed by the present applicant, according to which each block is provided with an autonomous vacuum source (see document No. EP 2 682 227 A1).

[0045] Whatever the structure and configuration of the blocks V, the latter are independent units that can be positioned as desired by the operator in the areas 110 free from slats 131, 132 according to the dimensions and shape of the plate L to be machined. Once the blocks V have been positioned, their bottom suction cups V1 are activated for fixing the blocks themselves to the first supporting surface 11. The plate L is then positioned on the blocks V, and the top suction cups V2 are then activated for holding the plate on the blocks. Once the plate has thus been held in a position raised both with respect to the sacrificial supporting surface 13 and with respect to the supporting surface 11, the working head H can be operated, after associating thereto, for example, a grinding tool G (FIG. 2) having a vertical axis, in such a way as to carry out a grinding machining operation on the peripheral lateral surface of the plate L, or any further necessary machining operation, for example, milling operations required to obtain recesses or openings in the plate L, by using a milling tool.

[0046] As is clearly apparent from the foregoing description, the basic idea forming the subject of the present invention consists in providing a work centre with a work surface that can be used both as a sacrificial supporting surface during a cutting operation and as a surface for arranging thereon blocks for supporting the plate during a grinding and/or milling operation on the plate. This is obtained by providing a supporting board, on which the sacrificial elements are arranged and configured in such a way that, on the one hand, an adequate support thereon is guaranteed for the plate that is to undergo a cutting operation and, on the other hand, there are left free portions of the supporting surface of the supporting board that are confined between the sacrificial elements and are distributed on the entire extension of the board, on which the blocks for supporting the plate that is to undergo a grinding and/or milling operation can be engaged. For this purpose, the distancing between the slats 131, 132 of each array is greater than a horizontal dimension of the suction-cup blocks V. In the case of blocks of a cylindrical shape, the aforesaid distancing is in any case greater than the maximum diameter of the blocks V.

[0047] Thanks to this simple arrangement, the user can have available a work centre that has a structure that is not more complex and/or more costly than a conventional work centre and that, notwithstanding this, is able to carry out both grinding or milling operations and cutting operations on plates of stone material. Elimination of the need for a machine dedicated just to cutting operations, and consequent elimination of the dead times necessary for transfer of a plate from a machine dedicated to the cutting operation to the numeric-control work centre that carries out subsequent machining operations on the plate, results in an immediate advantage, from the standpoint of productivity of the plant, overall costs of production, and space occupied in the plant.

[0048] Naturally, without prejudice to the principle of the invention, the details of construction and the embodiments may vary widely with respect to what is described and illustrated herein purely by way of example, without thereby departing from the scope of the present invention.