Pneumatic hand grinding tool

Abstract

A pneumatic hand grinding tool has a supporting plate and a compressed-air pipe to be connected to a source of compressed air for driving the supporting plate. The supporting plate has a flat surface to which an abrasive sheet is to be attached by suction. For this purpose the supporting plate has ducts leading into the flat surface, which are connected to an ejector unit that forms a source of suction. The ejector unit is arranged on the tool and has members which connect the ejector unit to the compressed-air pipe.

1 . A pneumatic hand grinding tool, which has a supporting plate ( 11 ) and a compressed-air pipe ( 4 ) to be connected to a source of compressed air for driving the supporting plate, the supporting plate ( 11 ) having a flat surface to which an abrasive sheet ( 48 ) is to be attached by suction, and the supporting plate ( 11 ) having for this purpose ducts ( 41 ,  42 ,  43 ,  44 ,  45 ) leading into the flat surface, which are connected to a source of suction ( 18 ), characterised in that the ducts ( 41 ,  42 ,  43 ,  44 ,  45 ) are connected to an ejector unit ( 16 ) forming the source of suction, the ejector unit being arranged on the tool and having means ( 21 ,  47 ) for connecting the ejector unit to the compressed-air pipe ( 4 ) with a view to providing the attachment by suction.  
     
     
         2 . A tool according to    claim 1   , characterised in that the ejector unit ( 16 ) comprises at least two ejectors ( 18 ), which are connected to at least two separate duct systems ( 27 ,  22 ,  34 ,  41 ,  42  and  28 ,  23 ,  35 ,  43 ,  44 ,  45 ) comprising the ducts ( 41 ,  42  and  43 ,  44 ,  45 ) connected to the respective ejectors ( 18 ).  
     
     
         3 . A tool according to    claim 2   , characterised in that the flat surface of the supporting plate ( 11 ) is divided, with the aid of sealing means ( 46 ), into sections which are separated from each other and associated with the respective duct systems ( 27 ,  22 ,  34 ,  41 ,  42  and  28 ,  23 ,  35 ,  43 ,  44 ,  45 ).  
     
     
         4 . Supporting plate for use in a pneumatic hand grinding tool according to    claim 2   , characterised in that the flat surface of the supporting plate is divided, with the aid of sealing means ( 46 ), into sections which are separated from each other and associated with the respective duct systems ( 27 ,  22 ,  34 ,  41 ,  42  and  28 ,  23 ,  35 ,  43 ,  44 ,  45 ).