Spindle locking apparatus for a rotary power tool

A user-manipulated spindle locking apparatus for a tool having a cylindrical spindle supported for rotation within a tubular housing, where said spindle locking apparatus is axially shiftable to engage a flat-sided portion of said spindle to prevent rotation of said spindle, said locking apparatus comprising:

• a locking sleeve disposed in an annular cavity between said spindle and said tubular housing, said locking sleeve having an inner periphery portion shaped to lockingly engage the flat-sided portion of said spindle;
• a locking collar surrounding said tubular housing radially outboard of said locking sleeve, and axially shiftable on said tubular housing, where said locking collar includes left and right halves that are joined around said tubular housing, and mutually fastened;
• first and second axial slot openings in said tubular housing;
• and
• first and second drive pins extending through said first and second axial slot openings to mechanically couple said locking collar to said locking sleeve, each such drive pin having an outboard end retained in said locking collar, and an inboard end retained in said locking sleeve, whereby said spindle is prevented from rotating when said locking collar is axially shifted as permitted by an interface between said drive pins and said axial slot openings to bring said inner periphery portion of said locking sleeve into locking engagement with the flat-sided portion of said spindle.