Transmission extension adapter for power hand tool

A transmission extension adapter for connecting a work head to a chuck of a power hand tool, the transmission extension adapter comprising:

• a cylindrical cap shell for connection to said power hand tool to accommodate said chuck, said cylindrical cap shell having a plurality of through holes, in each of which a positioning member is accommodated;
• an axle sleeve having an end rotatably connected to said cylindrical cap shell and at least one locating hole at a periphery thereof for receiving at least one of said positioning members;
• a transmission axle inserted through said axle sleeve and provided with an end for connection to said chuck of said power hand tool;
• a multi-angle positioning device for locking said axle sleeve to said cylindrical cap shell, said multi-angle positioning device comprising
• a locating ring sleeved onto said cylindrical cap shell and provided with a plurality of axially extending suspension arms, each said suspension arm having a holding down block, the holding down blocks of said suspension arms being respectively inserted into said through holes of said cylindrical cap shell and elastically and respectively pressing on said positioning members;
• and
• a collar sleeved onto and rotatable relative to said locating ring, said collar having a plurality of pressure members movable with rotary motion of said collar relative to said locating ring between a locking position where said pressure members press on said holding down blocks of said suspension arms against said positioning members and an unlocking position where said pressure members are released from said holding down blocks of said suspension arms;
• a front cap assembly fastened to an opposite end of said axle sleeve opposite to said cylindrical cap shell;
• and
• a supplementary chuck received inside said front cap assembly and connected to an opposite end of said transmission axle opposite to said chuck of said power hand tool for chucking said work head.