Pneumatically operated grinding apparatus

In a pneumatically operated grinding apparatus having dust removal means, comprising an apparatus housing, in which a work plate which is driven by a compressed-air motor is movably supported, an inlet piping connection for compressed air connected in fluid circuit with an inlet opening of said compressed-air motor, a suction piping connection which is connected to the inside of the apparatus housing and to which a suction device can be connected, and a discharge-air piping connection which is connected to an outlet of said compressed-air motor, each of said inlet opening, said discharge-air piping and said suction piping means including passageway means to the exterior of said apparatus housing, the improvement comprising wherein said discharge-air piping connection surrounds said inlet piping connection, wherein said suction piping connection surrounds said inlet piping connection and said discharge piping connection, wherein separate flexible hoses are sealingly connected to said inlet piping connection, said discharge-air piping connection and said suction piping connection, wherein an adapter is provided, to which each of said flexible hoses, which come in the same direction from said inlet piping connection, said discharge-air piping connection and said suction piping connection, are sealingly connected, said adapter having separate axially arranged hose connecting tubes, one sealingly connected to said hose extending to said inlet piping connection, another sealingly connected to said hose extending to said discharge-air piping connection and still another sealingly connected to said hose extending to said suction piping connection, said adapter further having outlet openings aligned in different direction for connection to a compressed-air source, a discharge-air port and a suction device.