Patent Publication Number: US-2022234251-A1

Title: Workbench for supporting and moving articles and machine for machining and cutting articles

Description:
The present invention relates to a workbench for supporting and moving articles made of stone, glass, ceramic or metallic material during a machining process. 
     Furthermore, the present invention relates also to a machine for cutting and machining the articles, comprising the aforementioned supporting and movement workbench. 
     The workbench may be used in combination with machines for cutting sheet-like articles by means of a water jet, which normally contains granules of abrasive material, if necessary in combination with a cutting tool, for example a cutting disc. 
     Generally, these machines comprise a workbench for supporting the articles, a unit for machining the articles and means for moving the machining unit above the supporting workbench. For example, the machining unit may comprise water jet cutting means comprising a nozzle, if necessary in combination with disc cutting means. 
     The movement means of the machining unit may comprise two lateral structures and a beam positioned above and transversely with respect to the lateral structures and supported by the same at its ends. The beam is able to slide along the lateral support structures. 
     The movement means may also comprise a carriage mounted slidably on the beam and a sleeve mounted on the carriage and able to move vertically relative thereto. A head or fork member, on which the cutting means are mounted, is connected to the bottom end of the sleeve. 
     Alternatively, the movement means may also be different from those indicated above and may comprise, for example, an anthropomorphic robot. 
     In the case where the machining unit comprises water jet cutting means, the supporting workbench comprises a tank which is normally filled with water and on top of which an interchangeable metal grille is placed. 
     The water tank has the function not only of recovering the water containing the abrasive material used during the cutting process, but also of cushioning the violent impact of the water jet emitted from the nozzle and passing through the article. 
     When the machining unit also comprises a disc cutting tool, a sacrificial surface may be positioned on the grille so as to take up the incisions by the disc cutting tool and avoid the impact of the disc with the metal grille, which would otherwise damage the grille itself. 
     For example, the documents EP1740359 and WO2014167470 describe machines for machining articles of the type described above. 
     One drawback of these solutions is that the workbench for supporting the articles is fixed, namely it may not be tilted and/or inclined with respect to the horizontal. 
     Therefore, the positioning and removal of the articles onto and from the workbench by an operator, even if suitable instruments and auxiliary devices such as a jib crane equipped with grippers or suction means are used, are particularly difficult and complex to perform, resulting also in an increase in the overall machining time. 
     In order to overcome at least partially said drawback, supporting workbenches have been developed with a support surface which is able to be tilted relative to a fixed frame and on which the article to be machined is positioned. 
     In particular, the support surface is movable between a horizontal position and an inclined or tilted, nearly vertical, position, with an edge close to the ground. The movement of the surface is performed by means of suitable movement means. 
     The surface is kept in the horizontal position when it is required to proceed with cutting or machining of the article and is arranged in the inclined position when the operator must load the article onto the surface or unload the cut or machined parts from the surface. 
     US20160207223 discloses a tilting workbench of the type indicated above, comprising a pair of movement mechanisms located on opposite sides with respect to the surface and each having a pair of hinged rigid elements, or connecting rods, and a hydraulic actuator. The frame, the surface and the connecting rods form a hinged quadrilateral. 
     Each of the rigid elements is hinged at one end with the fixed frame of the workbench and at the other end with the tilting surface; the actuator is hinged at one end with the fixed frame and the free end of the piston of the actuator is hinged with one of the two rigid elements. 
     Inclination of the support surface from the horizontal position into the inclined position is performed by activating the actuator which operates the rigid element to which it is connected so as to perform a rotary translational movement of the surface. Therefore, the rigid elements allow the rotary translational movement of the surface initially performed by the activation of the actuator. 
     U.S. Pat. No. 4,397,245 discloses a titling workbench similar to that described above and comprising a first and a second actuator for moving the surface from the horizontal position into the inclined position. 
     In particular, the first actuator is hinged with the fixed frame, while the end of the piston of the actuator is hinged with the support surface so as to raise it relative to the frame after being activated. 
     Also envisaged is a pair of rigid bars hinged together at one end, while the other two ends are hinged, respectively, with the support surface and the frame. These bars are moved by a second actuator arranged between one of the rigid bars and the frame. 
     When the support surface is in the horizontal position, the bars are superimposed on each other for displacement of the support surface into the inclined position and the second actuator is activated so as to raise the bars and align them along a diagonal so that they act as a support for the inclined surface. 
     One drawback of these solutions consists in the fact that the trajectory of the support surface from the horizontal position into the inclined position, and vice versa, is predefined and may not be modified. 
     Another drawback consists in the fact that it is not possible to adjust the movement trajectory of the surface depending on the free dimensions of the machine in which the supporting workbench is installed. 
     A further drawback consists in the fact that these supporting workbenches do not allow adjustment of the displacement trajectory of the titling surface depending on the type of article to be loaded onto the support surface. 
     These drawbacks do not allow the operator to choose an optimum trajectory for manoeuvring the support surface and therefore loading the articles and unloading the cut or machined parts in an easy manner. Moreover, these drawbacks result in an increase in the overall machining time. 
     A further drawback of the solutions indicated above consists in the fact that the operator is unable to programme displacement trajectories of the surface which are predefined and different from each other depending on the operating requirements. 
     The main object of the present invention is to provide a workbench for supporting and moving articles and a machine for cutting and machining the articles which are able to overcome the aforementioned drawbacks. 
     A particular task of the present invention is to provide a supporting and movement workbench which allows its displacement trajectory to be adjusted depending on the operating conditions. 
     A further task of the present invention is to provide a supporting and movement workbench which allows its displacement trajectory to be adjusted depending on the dimensions of the machine in which it is installed. 
     Another task of the present invention is to provide a supporting and movement workbench which simplifies the operations for loading and unloading the articles and provides a stable support for them during machining. 
     A further task of the present invention is to provide a supporting and movement workbench which is able to reduce the overall movement time and therefore machining time. 
     Another task of the present invention is to provide a supporting and movement workbench which allows the programming of different movement trajectories of the tilting surface depending on the operating requirements. 
     The object and the main tasks described above are achieved with a workbench for supporting and moving articles and its method of operation according to claims  1  and  16 , respectively, and with a machine for cutting and machining articles comprising the aforementioned supporting workbench according to claim  15 . 
    
    
     
       In order to illustrate more clearly the innovative principles of the present invention and its advantages compared to the prior art, non-limiting examples of embodiment will be described below with the aid of the accompanying drawings. In the drawings: 
         FIG. 1  shows a perspective view of the workbench for supporting and moving articles according to the present invention; 
         FIG. 2  shows a perspective view of a machine for cutting and machining articles according to the present invention and comprising the supporting and movement workbench according to  FIG. 1 ; 
         FIGS. 3 a -3 c    shows schematic side views of the supporting and movement workbench according to  FIG. 1  during operation. 
     
    
    
     With reference to the figures, a workbench is shown for supporting and moving articles during a machining process, denoted overall by the reference number  1 . 
     Preferably, the articles are made of stone, glass, ceramic or metallic material. However, the articles may also be made using different materials without thereby departing from the scope of protection of the present invention. Moreover, the articles preferably have a sheet-like form. 
     Preferably, the supporting and movement workbench  1  is designed to be mounted in a cutting and machining machine  2 , in particular a cutting machine with interpolated axes, of the type shown in  FIG. 2 . 
     However, the supporting and movement workbench  1  may also be used independently in a plant or line for machining articles or may be mounted in a machine different from that indicated above, without thereby departing from the scope of protection of the present invention. 
     In a manner known per se, the machine  2  comprises, in addition to the supporting and movement workbench  1 , a unit  4  for cutting and/or machining the articles and means  6  for moving the cutting and/or machining unit  4  above the supporting and movement workbench  1 , as shown in  FIG. 2 . 
     Conveniently, the movement means  6  of the cutting and/or machining unit  4  comprise two lateral support structures or shoulders  8  and a beam  10  positioned above the lateral structures  8  and slidably supported by the same at its ends. The beam  10  is therefore able to slide along the lateral support structures  8 . 
     The lateral support structures  8  and the remaining part of the structure of the machine  2  define a working area inside which the supporting workbench  1  is positioned. 
     The movement means  6  comprise a carriage  12  mounted slidably on the beam  10  and a sleeve  14  mounted on the carriage  12  and slidable relative thereto along a vertical direction. 
     The cutting and machining unit  4  is mounted on the bottom end of the sleeve  14  and may comprise a head or fork member  16  rotatable with respect to the sleeve  14  and able to be moved away or towards the support surface of the workbench  1 . 
     In the embodiment shown, the cutting and/or machining unit comprises disc cutting means  18  and water jet cutting means  20  mounted on the head or fork  16 . The water jet preferably contains in a manner known per se an abrasive material. 
     Conveniently, the disc cutting means  18  comprise a motorized spindle or electro-spindle supported by the head or fork member  16  for rotation of the disc, while the abrasive water jet cutting means  20  comprise a nozzle. 
     Obviously, the machining unit  4  may also comprise only the disc cutting means  18  or only the abrasive water jet cutting means  20 . 
     In a preferred embodiment of the invention, shown more clearly in  FIGS. 1 and 3   a - 3   c,  the supporting and movement workbench  1  comprises a fixed frame or base  22  in contact with the ground and a surface  24  for supporting the articles. 
     The support surface  24  is able to be tilted with respect to the frame  22  and moved from an initial horizontal position parallel to the ground, shown in  FIG. 3 a   , into a final position inclined with respect to the horizontal, close to the vertical, shown in  FIG. 3 c   , and vice versa. 
     The movement of the support surface  24  from the initial horizontal position into the final inclined position is performed preferably by means of rotary translation of the surface  24 . 
     The terms “initial” and “final” are used in the context of the present description only as reference terms; it is quite possible for the inclined position to correspond to the initial position during the rotary translational movement of the support surface  24  and for the horizontal position to correspond to the final position during the rotary translational movement of the support surface  24 . 
     The support surface  24  defines a leaning surface for the article; the cutting or machining of the articles by the cutting and machining unit  4  is performed when the support surface  24  is in the horizontal position. 
     Advantageously, unloading of the cut parts of the article, in particular when they have small dimensions, may be performed when the support surface  24  is in the initial horizontal position; when the support surface  24  is in the inclined, nearly vertical, final position, both loading of the articles and unloading of the cut or machined parts of the article may be performed. 
     Conveniently and preferably, the frame  22  delimits laterally a tank  26  designed to contain water and having an upper opening. The tank  26  is intended to be used for recovery of the water with the abrasive material used during cutting of the articles by means of a water jet and also for cushioning the violent impact of the water jet emitted from the nozzle and passing through the material of the article. 
     When the support surface  24  is in the working position, it is arranged horizontally and lies on top of the upper opening of the tank  26  (see  FIG. 3 a   ) which is therefore closed by the support surface  24 ; the support surface  24  is instead in the loading/unloading position when it has a predetermined inclination with respect to the ground, close to the vertical position (see  FIG. 3 c   ). 
     In this position, an edge  28  of the surface  24  is located close to the ground at a predetermined height h 1  from the ground and external to the perimeter of the frame  22  (see  FIG. 3 c   ). 
     Advantageously, the support surface  24  may be formed by a metal grille  25  (see  FIG. 1 ) and by a possible sacrificial surface. The sacrificial surface may consist of a wooden board or elements made of plastic material or rubber which are inserted straddling the profiles which form the grille. The sacrificial surface protects the metal grille against incisions by the disc cutting means. 
     Conveniently, the tilting surface  24  could optionally also comprise means, not shown in the figures, for provisionally locking the article in position, so as to prevent the cut and/or machined parts of the article from falling or being displaced during the movement of the support surface  24 . The locking means are of a type known per se and therefore will not be further described below. 
     The workbench  1  also comprises a rigid element  30 , shaped in the manner of a rocker arm and hinged with the frame  22 , in particular with the base of the frame  22 , at a pivoting point P. Preferably, the pivoting point P is located in the vicinity of the middle point of the frame  22 , as shown in  FIGS. 3 a   - 3   c.  In the continuation of the present description, the rigid element will be identified as rocker arm  30  and therefore these two terms identify the same element. 
     The rocker arm  30  has a non-linear profile, preferably a broken-line profile, and comprises a first wing  32  and a second wing  34  located on opposite sides with respect to a vertical plane π passing through the pivoting point P, as shown in  FIG. 3 b   . Therefore, the pivoting point P is located between the first wing  32  and the second wing  34 . 
     The first wing  32  comprises an end portion  36  and an intermediate portion  40  arranged between the pivoting point P and the end portion  36 . 
     The end portion  36  of the first wing  32  is hinged directly on the support surface  24  at a predetermined hinging point and about an axis of rotation X 1 . 
     Instead, the second wing  34  comprises an end portion  38  hinged indirectly with the support surface  24  via a first actuator  44  described in detail in the continuation of the description. 
     The hinging point of the end portion  36  of the first wing  32  of the rocker arm  30  with the support surface  24  is positioned on or close to an edge of the tilting surface  24 , namely the edge  28  which is moved close to the ground when the surface  24  is in the final inclined position. 
     As shown in the embodiment of  FIG. 1 , the end portion  36  of the first wing  32  of the rocker arm  30  may have a profile bent relative to the intermediate portion  40  and the edge  28  of the surface  24  may have a flange  29  with a hole for hinging the end  36 . 
     The hinged condition of the edge  28  of the support surface  24  with the end portion  36  of the first wing  32  of the rocker arm  30  allows the relative rotation of the surface  24  and the end portion  36  about the horizontal axis of rotation X 1  passing through the hinging point during the rotary translational movement of the surface  24 . 
     The means for hinging the rocker arm  30  with the support surface  24 , such as those described below, are of the type known per se and therefore will not be further described. 
     The connection zone between the intermediate portion  40  of the first wing  32  and the second wing  34  has a convex shape with its convexity directed towards the base of the frame  22 , so as to allow the rotation of the rocker arm  30  about a horizontal axis X 2  passing through the pivoting point P. 
     Alternatively, according to an embodiment not shown in the figures, the shape of the intermediate portion  40  of the first wing  32  and the second wing  34  could also have a configuration different from that shown, provided that it maintains its convexity. 
     Advantageously, as shown in  FIG. 1 , the rocker arm  30  may be formed by a pair of similar shaped brackets  31  designed to be arranged alongside each other and joined together so as to form a housing interspace, the function of which will be explained below. 
     As already mentioned above, there is also provided at least one first actuator  44  having a first end  46  hinged with the rocker arm  30  and more precisely with the second wing  34  and a second end  48  hinged with the support surface  24 , as shown more clearly in  FIGS. 3 b    and  3   c.    
     It should be noted that the second end  48  of the first actuator  44  is hinged with the support surface  24  in a position remote from the edge  28  hinged with the end portion  36  of the first wing  32  of the rocker arm  30  and precisely in the central zone of the surface  24 , as shown in  FIGS. 3 b    and  3   c.    
     Furthermore, the first end  46  of the first actuator  44  is hinged with the rocker arm  30  at or close to the end portion  38  of the second wing  34 . 
     Advantageously, the first actuator  44  is configured and positioned to raise the support surface  24  with respect to the frame  22  into a predefined, intermediate. inclined position, shown in  FIG. 3   b.    
     In the intermediate position, the support surface  24  has an inclination relative to the horizontal smaller than the predetermined inclination of the support surface  24  in the inclined final position for loading/unloading indicated above and shown in  FIG. 3   c.    
     Moreover, in the intermediate inclined position, the edge  28  of the support surface  24  on which the end portion  36  of the first wing  32  of the rocker arm  30  is hinged is located at a height h 2  greater than the height h 1  of the edge  28  in the final loading/unloading position and its vertical projection is situated external to the perimeter of the frame  22 , as shown in  FIGS. 3 b    and  3   c.    
     It is pointed out that the intermediate inclined position is not a unique position, but may identify a series of positions between the horizontal initial position and the final inclined position for loading/unloading, provided that these positions satisfy the conditions indicated above. 
     Advantageously, the first actuator  44  comprises a cylinder  52  and a piston  50  slidable along the axis of the cylinder  52 ; preferably, the piston  50 , in particular its free end  48 , is hinged with the support surface  24  and the cylinder  52  is hinged with the rocker arm  30  at its end  46 , as shown in  FIG. 3   b.    
     In particular, the cylinder  52  of the first actuator  44  may be hinged with the rocker arm  30  at a hinging point situated between the end portion  38  of the second wing  34  of the rocker arm  30  and the pivoting point P. Advantageously, the cylinder  52  of the first actuator  44  is hinged on the end portion  38  of the second wing  34 . 
     Therefore, the cylinder  52  of the first actuator  44  is rotatable with respect to the second wing  34  of the rocker arm  30  about a horizontal axis X 3  located above the axis of rotation X 2 . 
     In fact, the movement of the support surface  24  from the initial horizontal position into the intermediate inclined position is obtained by means of extraction of the piston  50  of the first actuator  44  from a retracted position into an extended position and rotation of the cylinder  52  of the first actuator  44  about the end portion  38  of the second wing  34  of the rocker arm  30 . 
     Moreover, during the movement of the support surface  24  from the horizontal position into the intermediate position the end of the piston  50  rotates about a respective horizontal axis X 4  passing through the hinging point of the piston  50  with the support surface  24 . 
     In accordance with the present invention, the workbench  1  comprises movement means  54  for rotating the rocker arm  30  about the horizontal axis X 2  passing through the pivoting point P so as to move the surface  24  from the intermediate inclined position into the final inclined position, and vice versa. 
     Both the first actuator  44  and the movement means  54  for rotating the rocker arm  30  are connected to a control unit for selectively operating them. 
     In particular, the movement means  54  may be activated and adjusted selectively also during the movement of the support surface  24  from the horizontal position into the intermediate position performed by the first actuator  44 ; moreover, the first actuator  44  may be also be activated and adjusted selectively during the movement of the support surface  24  from the intermediate inclined position into the final inclined position for loading/unloading performed by the movement means  54 . 
     With this configuration it is possible to control in a precise and variable manner the movement trajectory of the support surface  24  from the initial horizontal position into the final inclined position, and vice versa, and to program the predefined displacement trajectories of the support surface  24 . 
     In a preferred embodiment, the movement means  54  comprise at least one second actuator  56  having a first end  58  hinged with the rocker arm  30  and a second end  60  hinged with the frame  22 , as shown more clearly in  FIG. 3   b.    
     Obviously, the second actuator  56  is connected to the control unit like the first actuator  44  so that its mode of operation is similar to that described above. 
     Conveniently, the second actuator  56  may be hinged with the rocker arm  30  on the first wing  32 , in particular on the intermediate portion  40 , even more preferably along the connection zone between the intermediate portion  40  and the end portion  36  described above, as can be clearly seen in  FIG. 3   b.    
     Advantageously, as mentioned above, the intermediate portion  40  and the end portion  36  of the first wing  32  define a broken-line profile with its concavity directed towards the base of the frame  22  in the region of the connection zone, so as to allow the housing and the rotation of the second actuator  56 . 
     Furthermore, the second actuator  56  is hinged with the frame  22  at a different point remote from the pivoting point P, but positioned in any case along the base of the frame  22 . 
     In a similar manner to that described for the first actuator  44 , the second actuator  56  comprises a cylinder  62  hinged with the fixed frame  22  and a piston  64  slidable along the axis of the cylinder. 
     As shown in  FIG. 3 b   , the piston  64  comprises the end  58  hinged with the rocker arm  30 , in particular in the interconnection zone between the intermediate portion  40  and the end portion  36 . 
     As shown in  FIG. 1 , the ends  46  and  58  of the actuators  44  and  56  are hinged with both the brackets  31  of the rocker arm  30  indicated above and are positioned in the interspace between the brackets  31 . 
     Furthermore, the first actuator  44  and the second actuator  56  may be both of the pneumatic or hydraulic type. 
     Advantageously, the rotation of the rocker arm  30 , in particular the rotation of the first wing  32  with the end portion  36  downwards, so as to allow the movement of the support surface  24  from the intermediate inclined position into the final inclined position for loading/unloading, is performed by retracting the piston  64  of the second actuator  56  and rotating the cylinder  62  of the second actuator  56  about the horizontal axis X 5  passing through the hinging point of the cylinder  62  on the fixed frame  22 , as shown in  FIG. 3   b.    
     Furthermore, during the movement of the support surface  24  from the intermediate inclined position into the final inclined position, the end  58  of the piston  64  rotates relative to the rocker arm  30  about a respective horizontal axis X 6 . For the sake of easier illustration, all the reference symbols/numerals relating to the axes of rotation have been shown in  FIG. 3   a.    
     Instead, the rotation upwards of the rocker arm  30  so as to position the surface  24  in the intermediate inclined position is performed by means of rotation of the second actuator  56  in the opposite direction to that described above and by means of sliding of the piston  64  from the retracted position shown in  FIG. 3 c    into the extended position shown in  FIG. 3   b.    
     It can be seen that the movement of the support surface  24  from the intermediate inclined position into the final inclined position is not hindered by the fixed frame  22  since, during the first movement phase, performed with the first actuator  44 , the surface  24  is positioned with its edge  28  external to the volume of the fixed frame  22 . 
     If this feature were not present, the edge of the surface  24  would strike against the edge of the frame  22  during the movement of the surface  24  from the intermediate inclined position into the final inclined position. 
     In an alternative embodiment not shown in the figures, the movement means could also comprise a second actuator comprising a cylinder hinged on the top part of the frame, instead of on the bottom part, and a piston with an end hinged with the first wing of the rocker arm. 
     In this alternative embodiment, the second actuator would be designed to push the rocker arm downwards so as to cause the downwards rotation of the rocker arm by means of extraction of the piston. 
     Furthermore, considering the rocker arm  30 , the first actuator  44  and the second actuator  56  described above as a unit for moving the surface  24 , the workbench  1  may have two movement units located on two opposite sides of the surface  24 . This embodiment is not shown in the figures. 
     In accordance with alternative embodiments of the invention not shown in the figures, the actuators could also be different from those described above and could comprise, for example, gearmotors axially aligned on pins or racks with a swing bar. 
     The present invention also relates to a method of operation of the supporting and movement workbench  1  described above, which comprises the following steps: 
     a) arranging the workbench  1  with the support surface  24  in an initial horizontal position; in this position the piston  50  of the first actuator  44  is in the retracted position relative to its cylinder  52  while the piston  64  of the second actuator  56  is in an extended position relative to its cylinder  62 ; 
     b) activating the first actuator  44  by extracting the piston  50  and rotating the cylinder  52  about the end portion  38  of the second wing  34  of the rocker arm  30  so as to position the support surface  24  in the intermediate inclined position described above and shown in  FIG. 3   b;    
     c) activating the second actuator  56  by sliding the piston  64  so as to bring it into the retracted position and rotating the cylinder  62  about the axis X 5  passing through the hinging point on the fixed frame  22  so as to rotate the rocker arm  30  about the pivoting point P and position the support surface  24  in the final inclined position for loading/unloading shown in  FIG. 3   c.    
     As mentioned above, during the steps b) and c), the ends  48 ,  58 , respectively, of the pistons  50 ,  64  rotate respectively relative to the support surface  24  and the rocker arm  30  about the respective hinging points. 
     Obviously, the method also involves a second phase, namely that during which the support surface  24  performs the opposite movement, namely from the final inclined position into the intermediate inclined position and from the latter into the initial horizontal position, carrying out in the reverse order the steps indicated above. 
     The method differs from the prior art in that it envisages a control unit connected to the actuators and configured to control the selective activation of the first actuator  44  and, where necessary, of the second actuator  56  during the movement of the support surface  24  from the initial horizontal position into the intermediate inclined position, and the activation of the second actuator  56  and, if necessary, of the first actuator  44  during the movement of the support surface  24  from the intermediate inclined position into the final inclined position for loading/unloading. 
     Therefore, the actuators  44 ,  56  may be activated both sequentially and simultaneously, depending on the operating requirements, or at different or the same speeds. 
     In this way, the operator has the possibility of controlling and adjusting continuously the displacement trajectory of the support surface from the horizontal position into the final inclined position for loading/unloading. 
     From the above description, it is now clear how the supporting and movement workbench and the machining and cutting machine according to the present invention are advantageously able to achieve the predefined objects. 
     In particular, since the workbench comprises at least one first actuator and one second actuator connected to the control unit, the operator has the possibility of adjusting at any time the displacement trajectory of the support surface by operating the actuators. 
     The operator may also program predefined displacement trajectories of the surface which are different from each other depending on the operating conditions to be adopted or the type of article to be machined. 
     Therefore, the supporting workbench according to the present invention helps to simplify and speed up the operations of loading/unloading the articles and reduce the overall machining times. 
     Obviously, the above description of the embodiments applying the innovative principles of the present invention is provided by way of example of these innovative principles and must therefore not be regarded as limiting the scope of the rights claimed herein. 
     For example it is also possible to envisage different types of components or different forms and configurations of the elements, such as the form or configuration of the shaped rigid element or rocker arm.