Chuck unit for automatic machine tools, designed to perform both power tasks and finishing work

Abstract

This invention relates to a chuck unit for automatic machine tools, designed to perform both power tasks and high-speed finishing of pieces, with lubricant/coolant fluid flowing through the chuck shaft, which includes: a support ( 1 ) on which a chuck ( 4 ) for a power tool is mounted, the said chuck being driven by a first motor ( 2 ) a second chuck ( 5 ) mounted inside the previous one and coaxial with it, which is driven by a second independent motor ( 18 ), means ( 12 ) designed to discharge the pull of the power tool ( 4 ) onto the said support being fitted. The result is a unit which can receive different types of tool and perform different types of task, for which it has so far been most advantageous to use two separate machines.

1 . Chuck unit for automatic machine tools, characterised in that it comprises two independent chucks ( 4 ,  5 ), mounted coaxially, designed to receive different tools, the seatings for the said tools also being coaxial and located on the same side of the chuck unit.  
     
     
         2 . Chuck unit for automatic machine tools as claimed in    claim 1   , characterised in that the said chucks ( 4 ,  5 ) are mounted one inside the other.  
     
     
         3 . Chuck unit for automatic machine tools as claimed in    claim 2   , characterised in that the said chucks ( 4 ,  5 ) are activated by independent motors ( 2 ,  18 ).  
     
     
         4 . Chuck unit for automatic machine tools as claimed in    claim 2   , characterised in that it includes a pair of flanges, pushed by elastic means ( 12 ), which pull the shaft ( 11 ) on which the tool cone gripper ( 10 ) is fitted into the closed position, and discharge the pull onto the structure of the assembly.  
     
     
         5 . Chuck unit for automatic machine tools as claimed in    claim 4   , characterised in that it includes: 
 a support ( 1 ) on which a chuck ( 4 ) for a power tool is mounted, the said chuck being driven by a first motor ( 2 )    a second chuck ( 5 ) mounted inside the previous one and coaxial with it, which is driven by a second independent motor ( 18 ),    means ( 12 ) designed to discharge the pull of the power tool ( 4 ) onto the said support being fitted.    
     
     
         6 . Chuck unit for automatic machine tools as claimed in    claim 4   , characterised in that the said chucks ( 4 ,  5 ) are driven by the same motor ( 18 ).  
     
     
         7 . Chuck unit for automatic machine tools as claimed in    claim 3   , characterised in that it includes: 
 a support ( 1 );    a sleeve ( 33 ) fixed to the said support;    a power chuck ( 4 ) fitted to the said sleeve ( 33 ), which said power chuck ( 4 ) is driven by a motor ( 2 ) fitted to the said support;    a finishing chuck ( 5 ) fitted inside the said sleeve ( 33 ) coaxially with and inside the power chuck ( 4 );    a shaft being housed inside the said finishing chuck ( 5 ), at the end of which shaft ( 11 ) a tool cone gripper ( 10 ) is fitted, the said shaft being subject to the action of springs ( 12 ) which tend to push it backwards to lock the said gripper ( 10 );    a bushing ( 17 ) fitted to slide on the said finishing chuck ( 5 ) and driven by the drive motor ( 18 ) of the said chuck;    means ( 20 ) designed to push the said bushing ( 17 ) in the direction in which the said power ( 4 ) chuck retracts;    a second bushing ( 25 ) fitted to slide on the said finishing chuck ( 5 );    a piston ( 26 ) fitted inside the said second bushing ( 25 ) and subject to the action of elastic means ( 27 ) which engage the end wall of the said bushing ( 25 ) on one side and the said piston ( 26 ) on the other;    the action of the said elastic means ( 27 ) on one side pushes the said piston ( 26 ) to strike against stop means fitted in the rear part of the chuck unit, and on the other side pushes the said bushing ( 25 ) to engage with the said bushing ( 17 ), thus causing the front edge of the said bushing ( 17 ) to engage power chuck ( 4 ) or a wall integral with the said power chuck ( 4 );    the unit being also equipped with means designed to engage the said s shaft ( 11 ) in order to control its travel in relation to the said bushing, and cause gripper ( 10 ) fitted to the said shaft ( 11 ) to open and lock the cone of the tool which is inserted in the power chuck or finishing chuck.    
     
     
         8 . Chuck unit for automatic machine tools as claimed in    claim 7   , characterised in that it includes a second piston ( 23 ), coaxial with the said first piston ( 26 ), which is designed to engage the said piston ( 26 ) and push it to compress the said springs ( 27 ), a shaft ( 28 ) fitted with a gripper ( 30 ) designed to engage the rear end of the said first shaft ( 11 ) being located inside the said piston ( 23 ).  
     
     
         9 . Chuck unit for automatic machine tools as claimed in    claim 3   , characterised in that it includes: 
 a bushing ( 17 ) fitted to slide on the said finishing chuck ( 5 ), which said bushing is able to move between a position in which it rests with its front edge against a plate integral with the said power chuck ( 4 ) and a position in which the said bushing retracts from the said plate;    a second bushing ( 47 ) fitted to slide on shaft ( 11 ) behind the said first bushing ( 17 );    a flange ( 48 ) fitted to slide on shaft ( 11 ), which is able to move between a position in which it approaches the said bushing ( 47 ) and a position in which it moves away from the said bushing ( 47 );    a set of springs ( 60 ), located inside the said bushing ( 47 ), which tend to distance the said flange ( 48 ) from the said bushing ( 47 );    a pair of pistons ( 46 ) and ( 45 ) situated on opposite sides from the said bushing ( 47 ) and the said flange ( 48 );    a piston ( 24 ) fitted behind the said bushing ( 47 ) and designed to engage the said shaft ( 11 ) on which tool gripper ( 10 ) is fitted;    means designed to pump a pressurised fluid into the chambers in which the said ring-shaped pistons ( 45 ) and ( 46 ) are situated, so as to push the said pistons ( 45 ) and ( 46 ) towards one another, causing one of the said pistons ( 46 ) to engage a fixed stop ( 64 ) and the other (piston  45 ) to engage the said bushing ( 47 ), thus positioning flange ( 48 ).    
     
     
         10 . Chuck unit for automatic machine tools as claimed in    claim 3   , characterised in that a pair of flanges ( 62 ) and ( 63 ) are fitted between the said ring-shaped pistons ( 46 ) and ( 45 ), which said flanges are subject to the action of means ( 64 ) that tend to distance them, in order to separate the said pistons ( 45 ) and ( 46 ) from the said flanges ( 47 ) and ( 48 ).  
     
     
         11 . Chuck unit for automatic machine tools as claimed in    claim 2   , characterised in that it includes: 
 a pair of chucks fitted coaxiaily one inside the other, one designed to receive a power tool and the other a finishing tool    a shaft to which a tool cone gripper is fitted    a bushing fitted to slide on the inner chuck and connected to a drive motor, which said bushing is fitted with means designed to engage the said outer chuck, causing it to rotate    thrust means designed to keep the said bushing distanced from the said outer chuck    a pair of flanges, pushed by springs, which pull the shaft on which the tool cone gripper is fitted so as to close the said gripper, discharging the pull onto the structure of the assembly    means designed to act on the said bushing, counteracting the force exerted by the said thrust means so as to push the said bushing to engage with the said outer chuck.    
     
     
         12 . Tools for a chuck unit in accordance with    claim 1   , characterised in that the part of the cone between the connector for the gripper and the body of the tool is of such dimensions as to engage the corresponding seating without interfering with the seating of the second chuck.  
     
     
         13 . Chuck unit for automatic machine tools as claimed in    claim 5   , characterised in that said speed chuck ( 5 ) is mounted inside said power chuck ( 4 ).  
     
     
         14 . Chuck unit for automatic machine tools as claimed in    claim 3   , characterised in that said power chuck ( 4 ) is moved by a motor ( 80 ) house inside the said sleeve ( 33 ).