Keeper spring for connecting mining tool to work tool holder

The combination of a supporting block and pick-like bit member freely rotatably therein, hard inserted elements at one end thereof and cylindrical shank at the opposite end thereof, the shank being formed with an annular groove, said supporting body having a bore receiving said shank and formed with a recess opening in said bore, a keeper spring for rotatably mounting said pick-like bit member in said bore, said keeper spring comprising a generally cylindrical member made of a metallic spring material, said cylindrical member being split along the axial length thereof to define a first spring portion that is radially expansible and contractible, and said cyindrical member including a plurality of second spring portions disposed on the circumference thereof, each second spring portion being an elongaed arcuate leaf spring protuberance having each end joined to said cylindrical member and having the opposite side edges thereof being defined by two parallel slits cut into said cylindrical member, said second spring portion projecting radially outwardly of, and axially aligned with, said cylindrical member, the portions of said cylindrical member between said second spring portions being continuous cylindrical arcs having radii equal to the radii of the portions of said cylindrical member on either end of said protuberances, said keeper spring assembled on said shanking said groove and maintained in contact thereto by said first spring portion, said keeper spring as mounted on said shank being disposed within said bore of the supporting body, with the leaf spring protuberance disposed in said recess whereby the said second spring portion of the keeper spring is effective to limit axial movement of the bit member relative to the supporting body.