Apparatus for smoothing a product, in particular a semi-finished ceramic product

Abstract

An apparatus ( 1 ) for smoothing a product ( 2 ), in particular a semi-finished ceramic product, comprises: an abrasive tool ( 3 ) in the form of an endless belt ( 4 ) which is trained around at least one pair of pulleys ( 5, 6 ), at least one of which is power-driven; the belt ( 4 ) has an active section ( 7 ) and at least one passive section ( 8 ); the active section ( 7 ) removes material from the product ( 2 ), while the passive section ( 8 ) receives a regenerating treatment that restores the abrasive capacity of the tool ( 3 ); drive means ( 20 ) acting on the belt ( 4 ) in such a way as to enable the belt ( 4 ) itself to move in the space surrounding the product ( 2 ); means ( 10 ) for spraying a liquid on the belt ( 4 ), which has liquid absorption properties, said means ( 10 ) being located in the vicinity of the belt ( 4 ) itself; and negative pressure means ( 9 ) associated with the passive section ( 8 ) of the belt ( 4 ) and operating in such a way as to extract the liquid and the materials retained by the belt ( 4 ) and removed from the product ( 2 ) during the smoothing process.

1 . An apparatus ( 1 ) for smoothing a product ( 2 ), in particular a semi-finished ceramic product, comprising an abrasive tool ( 3 ) in the form of an endless belt ( 4 ) trained around at least one pair of pulleys ( 5 ,  6 ), at least one of which is power-driven; and having at least one active section ( 7 ) and at least one passive section ( 8 ); the active section ( 7 ) being adapted to remove material from the product ( 2 ) while the passive section ( 8 ) receives a regenerating treatment that restores the abrasive capacity of the tool ( 3 ); the apparatus ( 1 ) further comprising:
 drive means ( 20 ) acting on the belt ( 4 ) in such a way as to enable the belt ( 4 ) itself to move in the space surrounding the product ( 2 );   means ( 10 ), located in the vicinity of the belt ( 4 ), for spraying a liquid on the belt ( 4 ) itself, which has liquid absorption properties;   negative pressure means ( 9 ) associated with the passive section ( 8 ) of the belt ( 4 ) and operating in such a way as to remove the liquid and the process waste materials retained by it.   
   
   
       2 . The apparatus according to  claim 1 , wherein the spraying means ( 10 ) are nozzles designed to direct the liquid at a precise area of the belt ( 4 ). 
   
   
       3 . The apparatus according to  claim 1 , wherein the spraying means ( 10 ) are composed of a plurality of nozzles ( 10   a ) positioned in such a way as to face a portion of the passive section ( 8 ) of the belt ( 4 ), upstream of the negative pressure means ( 9 ) relative to a rotation direction (S) of the belt ( 4 ). 
   
   
       4 . The apparatus according to  claim 1 , wherein the negative pressure means ( 9 ) comprise a cylindrical roller ( 11 ) having an internal cavity ( 12 ) and external lateral surface ( 11   a ) through which at least one hole ( 11   b ) and which delimits a vacuum chamber ( 12 ) communicating with the outside through the hole/each hole ( 11   b ); the roller ( 11 ) being in direct contact with the passive section ( 8 ) of the belt ( 4 ). 
   
   
       5 . The apparatus according to  claim 4 , wherein the roller ( 11 ) is freely rotatable about its rotation axis ( 15 ). 
   
   
       6 . The apparatus according to  claim 5 , wherein the roller ( 11 ) is integrated into one of the pulleys ( 5 ,  6 ) around which the belt ( 4 ) is trained. 
   
   
       7 . The apparatus according to  claim 5 , wherein the roller ( 11 ) is a tensioner of the belt ( 4 ). 
   
   
       8 . The apparatus according to  claim 4 , wherein the lateral surface ( 11   a ) has a plurality of holes ( 11   b ) passing through it. 
   
   
       9 . The apparatus according to  claim 4 , wherein the lateral surface ( 11   a ) of the roller ( 11 ) has shoulders ( 16 ) that envelope the opposite longitudinal edges of the belt ( 4 ). 
   
   
       10 . The apparatus according to  claim 4 , wherein the roller ( 11 ) is coaxially and freely rotatable on a hollow pin ( 17 ) defining the cavity ( 12 ); the hollow pin ( 17 ) also having a slot ( 17   c ) facing the passive section ( 8 ) of the belt ( 4 ); the cavity ( 12 ) inside the hollow pin ( 17 ) being designed to remove the liquid and the smoothing process waste material by suction from the passive section ( 8 ) of the belt ( 4 ) through the roller ( 11 ), that is to say, through the holes ( 11   b ) in the lateral surface ( 11   a ) and through the slot ( 17   c ). 
   
   
       11 . The apparatus according to  claim 10 , wherein the hollow pin ( 17 ) is acted upon by vacuum generating means ( 31   m ) adapted to produce a negative pressure in the cavity ( 12 ) in such a way as to remove the process waste material by suction passing directly from the passive section ( 8 ) through the holes ( 11   b ) and slot ( 17   c ) in the pin ( 17 ). 
   
   
       12 . The apparatus according to  claim 10 , comprising means ( 18 ) for keeping the roller ( 11 ) in forced contact with the belt ( 4 ). 
   
   
       13 . The apparatus according to  claim 12 , wherein the forced contact means ( 18 ) comprise a mounting arm ( 18   a ) and elastic elements ( 19 ) interposed between the roller ( 11 ) and the first arm ( 22 ) and operating in such a way as to apply sufficient compression between the roller ( 11 ) and the belt ( 4 ). 
   
   
       14 . The apparatus according to  claim 1 , comprising a manipulatable structure ( 20 ), constituting said drive means, which mounts the belt ( 4 ) and the negative pressure means ( 9 ). 
   
   
       15 . The apparatus according to  claim 14 , wherein the structure ( 20 ) can be manipulated manually by an operator. 
   
   
       16 . The apparatus according to  claim 14 , wherein the structure ( 20 ) is associated with a mechanical and/or robot-controlled manipulator ( 21 ). 
   
   
       17 . The apparatus according to  claim 14 , wherein the structure ( 20 ) comprises a first swinging mounting arm ( 22 ) pivoted at ( 22   a ) to a support ( 23 ) connected to means ( 24 ) for connection to the manual or robot-controlled manipulator ( 21 ); a lower pulley ( 6 ) of the belt ( 4 ) being rotatably connected to the first arm ( 22 ), at the lower end of the first arm ( 22 ); the upper end of the arm ( 22 ) being associated with a counterweight ( 25 ) for balancing the center of gravity of the first arm ( 22 ) and of the belt ( 4 ), in such a way that the belt ( 4 ) can apply to the active section ( 7 ) a predetermined contact force on the product ( 2 ) in combination with the manipulator ( 21 ). 
   
   
       18 . The apparatus according to  claim 17 , wherein the first arm ( 22 ) is provided with adjustable limit stop and contact means ( 26 ) acting between the first arm ( 22 ) and the support ( 23 ) and designed to permit adjustment of at least one stable end position where the first arm ( 22 ) is angularly closest to the support ( 23 ) and where movement towards the belt ( 4 ) is stopped. 
   
   
       19 . The apparatus according to  claim 18 , wherein the limit stop and contact means ( 26 ) are located at two different points of the first arm ( 22 ) and each comprises a threaded rod ( 27 ) protruding transversally from the first arm ( 22 ) and screwed into a respective hole ( 28 ) made in the first arm ( 22 ); each rod ( 27 ) having an end head ( 29 ) designed to come into contact, in use, with respective zones of the support ( 23 ). 
   
   
       20 . The apparatus according to  claim 17 , wherein the lower pulley ( 6 ) is connected by its mounting shaft ( 6   a ), to the inside of a slot ( 30 ) made in the first arm ( 22 ) and in such a way that, when required, it can be moved to adjust the tension of the belt ( 4 ) by slackening the shaft ( 6   a ) from the slot ( 30 ). 
   
   
       21 . The apparatus according to  claim 17 , wherein the upper pulley ( 5 ) of the belt ( 4 ) is connected to a respective drive ( 5   m ) which is in turn mounted on a bracket ( 32 ) protruding from the first arm ( 22 ). 
   
   
       22 . The apparatus according to  claim 17 , comprising pushing means ( 100 ) composed of a control cylinder ( 101 ) mounted on the support ( 23 ) and acting on a roller ( 102 ) that is keyed to the first arm ( 22 ) and positioned eccentrically with respect to its pivot point ( 22   a ) in such a way that the belt ( 4 ) applies a predetermined contact force on the product ( 2 ) according to the pushing force exerted by the cylinder ( 101 ) on the eccentric roller ( 102 ); control means ( 103 ) being provided to act on the cylinder ( 101 ) and to activate and deactivate the cylinder ( 101 ) when required. 
   
   
       23 . The apparatus according to  claim 14 , wherein the mounting structure ( 20 ) comprises:
 a box-shaped frame ( 33 ) equipped at the top of it, with flange means ( 34 ) for connection to the manipulator ( 21 ) and mounting the spraying ( 10 ) inside it, the negative pressure means ( 9 ) acting at an arc-shaped passive section ( 8 ) of the belt ( 4 ) passing over the upper pulley ( 5 ) that is rotatably mounted inside the frame ( 33 ) and equipped with a respective drive ( 5   m );   a rigid support ( 35 ) associated with the box-shaped frame ( 33 ) and extending downwardly from the latter as far as the bottom end of the lower pulley ( 6 ) of the belt ( 4 ).   
   
   
       24 . The apparatus according to  claim 23 , wherein the support ( 35 ) is provided in the middle of it with an auxiliary idle wheel ( 36 ) that is rotatably connected to the support ( 35 ) and in bilateral contact with a protruding inside profile of the belt ( 4 ). 
   
   
       25 . The apparatus according to  claim 23 , wherein the spraying means ( 10 ), the negative pressure means ( 9 ) and the upper pulley ( 5 ) and its drive ( 5   m ) are mounted on a first member ( 60 ) located inside the frame ( 33 ), the first member ( 60 ) being pivoted at one end of it ( 60   a ) to the frame ( 33 ). 
   
   
       26 . The apparatus according to  claim 25 , comprising tensioning means ( 61 ) acting on the first member ( 60 ) and composed of a cylinder ( 62 ) located at the bottom of the frame ( 33 ), protruding vertically into the frame ( 33 ) and acting on an idle roller ( 63 ) connected, at ( 63   a ), to the first member ( 60 ) and positioned eccentrically with respect to the pivot point ( 60   a ) of the first member ( 60 ) so as to allow the member ( 60 ) to move in both directions in such a way as to move the upper pulley ( 5 ), thereby tensioning or slackening the belt ( 4 ). 
   
   
       27 . The apparatus according to  claim 26 , comprising control means ( 64 ) acting on the cylinder ( 62 ) and designed to activate and deactivate the cylinder ( 62 ), when required and in such a way as to control the force acting on the roller ( 63 ) and thus the tension of the belt ( 4 ). 
   
   
       28 . The apparatus according to  claim 25 , wherein the spraying means ( 10 ) and the negative pressure means ( 9 ) are made on a portion ( 37 ) of the first member ( 60 ); the portion ( 37 ) being pivoted to the first member ( 60 ) at ( 37   a ) in such a way as to enable the entire portion ( 37 ) to rotate between a lowered operating position, where the spraying and negative pressure means ( 10 ,  9 ) are in contact with the passive section ( 8 ) of the belt ( 4 ), and a raised, non-operating position where the spraying and negative pressure means ( 10 ,  9 ) are away from the upper pulley ( 5 ) and from the belt ( 4 ). 
   
   
       29 . The apparatus according to  claim 28 , wherein the negative pressure means ( 9 ) are composed of a closed cylindrical chamber ( 65 ) formed in the portion ( 37 ) and provided with a slit ( 65   a ) that can be positioned to face the passive section ( 8 ) of the belt ( 4 ) when the portion ( 37 ) is in the lowered position; the vacuum being generated inside the chamber ( 65 ) by respective means ( 65   b ) which enable the process waste material to be channeled out by suction through a pipe ( 65   c ). 
   
   
       30 . The apparatus according to  claim 28 , wherein the spraying means ( 10 ) comprise two sets of nozzles ( 10   a ) made on the portion ( 37 ) on opposite sides of the negative pressure means ( 9 ); each set of nozzles ( 10   a ) being connected to liquid supply means ( 10   b ) that can be individually activated in accordance with the rotation direction (S) of the belt ( 4 ) and in such a way that the belt ( 4 ) is sprayed before it moves past the negative pressure means ( 9 ). 
   
   
       31 . The apparatus according to  claim 28 , wherein means ( 38 ) are provided between the portion ( 37 ) and the first mounting member ( 60 ) for locking the portion ( 37 ) in the lowered operating position so that the negative pressure means ( 9 ) and the spraying means ( 10 ) can be positioned near the passive section ( 8 ) of the belt ( 4 ). 
   
   
       32 . The apparatus according to  claim 31 , wherein the locking means ( 38 ) comprise a vertical lever ( 39 ) pivoted at one end of it, at ( 39   a ), to the member ( 60 ) and acting at it its free opposite end on a pin ( 40 ) that protrudes laterally from the portion ( 37 ) and that can be positioned near the lever ( 39 ) when the portion ( 37 ) is in the lowered operating position; an elastic element ( 41 ) being interposed between the lever ( 39 ) and the member ( 60 ) so as to keep the lever ( 39 ) constantly in contact with the pin ( 40 ). 
   
   
       33 . The apparatus according to  claim 32 , comprising adjustable limit stop means ( 70 ) interposed between the portion ( 37 ) and the first member ( 60 ) and designed to enable the portion ( 37 ), when in the lowered position, to be positioned correctly relative to the belt ( 4 ); said means ( 70 ) comprising a bolt ( 70   a ) screwed into a threaded through hole made in the portion ( 37 ) in such a way that its lower end comes into contact with a surface of the member ( 60 ) when the portion ( 37 ) is in the lowered position. 
   
   
       34 . The apparatus according to  claim 1 , wherein the belt ( 4 ) has a quadrangular cross section and regular thickness. 
   
   
       35 . The apparatus according to  claim 1 , wherein the belt ( 4 ) has a quadrangular cross section and regular thickness with an internal protruding profile running along the middle of it. 
   
   
       36 . The apparatus according to  claim 1 , wherein the belt ( 4 ) is in the form of a “Moebius” belt trained around the two pulleys ( 5 ,  6 ).