Clamshell vacuum dust extraction apparatus for a percussive air tool

Vacuum dust extraction apparatus for an air tool that percussively drives an implement, said apparatus comprising:

• a retainer locked onto a barrel of said air tool with a retainer spring to retain an inboard end of said implement;
• a tubular bellows surrounding an exposed portion of the implement for containing workplace dust produced when the implement percussively impacts a workpiece;
• and
• a clamshell adaptor including first and second halves oppositely disposed about said retainer and joined to close around said retainer in a manner to secure said clamshell adaptor to said retainer, a tubular sleeve received within one end of said tubular bellows, an integral exhaust port coupled to a suction hose so that the workplace dust in said tubular bellows is drawn through said clamshell adaptor and into said suction hose, a sealing element that fills a gap between an inner periphery of said clamshell adaptor and an exterior periphery of said retainer to minimize suction loss through said clamshell adaptor, and semi-circular flanges formed on inboard ends of said first and second clamshell adaptor halves that abut an inboard end of said retainer when said first and second clamshell adaptor halves are joined to close around said retainer.