Tool

Abstract

In a tool comprising a supporting part and a disk-shaped working part for machining operation, the supporting part comprises a supporting face for the working part and a permanent magnet within the supporting face. The working part comprises a coupling member of ferromagnetic material which is movable into magnetically clinging connection with the permanent magnet upon application of a counterpart supporting face to the supporting face.

1 . A tool, comprising 
 a supporting part ( 1 ,  1 ′);    a disk-shaped working part ( 2 ,  2 ′) for machining operation; and    a common center line ( 6 );    wherein the supporting part ( 1 ) has a supporting face ( 5 ) for the working part ( 2 ,  2 ′) and, within the supporting face ( 5 ), at least one permanent magnet ( 14 ,  14 ′);    wherein the working part ( 2 ,  2 ′) has a counterpart supporting face ( 15 ) for the supporting face ( 5 ); and    wherein the working part ( 2 ,  2 ′) has a coupling member ( 19 ,  19 ′) of ferromagnetic material which is movable into magnetically clinging connection with the at least one permanent magnet ( 14 ,  14 ′) upon contact of the counterpart supporting face ( 15 ) with the supporting face ( 5 ).    
   
   
       2 . A tool according to  claim 1 , wherein the at least one permanent magnet ( 14 ,  14 ′) is disposed in a recess ( 11 ,  11 ′) of the supporting part ( 1 ,  1 ′); and wherein the coupling member ( 19 ,  19 ′) enters into the recess ( 11 ,  11 ′).  
   
   
       3 . A tool according to  claim 2 , wherein the recess ( 11 ,  11 ′) has a non-circular cross-sectional shape; and wherein the coupling member ( 19 ,  19 ′) has a non-circular cross-sectional shape that conforms to the cross-sectional shape of the recess ( 11 ,  11 ′).  
   
   
       4 . A tool according to  claim 3 , wherein the recess ( 11 ) and the coupling member ( 19 ,  19 ′) have a polygonal cross-sectional shape.  
   
   
       5 . A tool according to  claim 4 , wherein the recess ( 11 ,  11 ′) and the coupling member ( 19 ,  19 ′) have a cross-sectional shape of an equilateral and equiangular polygon.  
   
   
       6 . A tool according to  claim 2 , wherein the coupling member ( 19 ) has a circular centering shoulder ( 21 ) that conforms to the recess ( 11 ).  
   
   
       7 . A tool according to  claim 1 , wherein the supporting part ( 1 ,  1 ′) comprises a supporting casing ( 3 ) and a retainer ( 10 ,  10 ′) which is at least sectionally encased by the supporting casing ( 3 ).  
   
   
       8 . A tool according to  claim 7 , wherein the supporting casing ( 3 ) consists of plastics.  
   
   
       9 . A tool according to  claim 7 , wherein the retainer ( 10 ,  10 ′) consists of metal.  
   
   
       10 . A tool according to  claim 1 , wherein the supporting part ( 1 ,  1 ′) comprises a connection to a rotary drive unit.  
   
   
       11 . A tool according to  claim 1 , wherein the working part ( 2 ,  2 ′) is comprised of abrasive material ( 16 ) on a backing ( 17 ).  
   
   
       12 . A tool according to  claim 8 , wherein the supporting casing ( 3 ) consists of flexibly resilient material.  
   
   
       13 . A tool according to  claim 1 , wherein 5≦D 19 /d 19 ≦100 applies to the ratio that the greatest diameter (D 19 ) of the coupling member ( 19 ) bears to the thickness (d 19 ) thereof.  
   
   
       14 . A tool according to  claim 1 , wherein 1<D 2 /D 19 ≦10 applies to the ratio that the greatest diameter (D 2 ) of the working part ( 2 ) bears to the greatest diameter (D 19 ) of the coupling member ( 19 ).  
   
   
       15 . A tool according to  claim 4 , wherein the recess ( 11 ′) and the coupling member ( 19 ′) have flanks ( 12 ′,  20 ′) that are bent inwards.  
   
   
       16 . A tool according to  claim 15 , wherein respectively adjacent flanks ( 12 ′) of the recess ( 11 ′) and respectively adjacent flanks ( 20 ′) of the coupling member ( 19 ′) are joined to each other by rounded corners ( 22 ,  23 ).  
   
   
       17 . A tool according to  claim 15 , wherein the flanks ( 12 ′) of the recess ( 11 ′) incline towards each other from the supporting face ( 5 ) into the supporting part ( 1 ′).  
   
   
       18 . A tool according to  claim 1 , wherein several permanent magnets ( 14 ′) are disposed in the supporting part ( 1 ′).  
   
   
       19 . A tool according to  claim 18 , wherein the permanent magnets ( 14 ′) are disposed at equal angular distances and at a distance from the center line ( 6 ).  
   
   
       20 . A tool according to  claim 11 , wherein the working part ( 2 ,  2 ′) is pliable.