Sleeve plug for attachment to a spindle head

A sleeve-plug assembly attachable to a spindle head of the type having a generally cylindrical body and a bore extending axially into one end thereof, the assembly including the combination of

• an adjusting nut;
• an adjustable adapter insertable into said bore, said adapter having a threaded end protruding from the spindle head to threadedly receive said adjusting nut;
• a sleeve assembly slidable onto the end portion of the spindle head over said nut, said sleeve assembly comprising
• an axially shiftable carrying bushing having aperture means for receiving a plurality of locking balls annularly disposed around said bushing, the portion of said bushing adjacent said balls having a radial thickness smaller than the ball diameters,
• a locking bushing having an end portion surrounding said nut and a sleeve portion generally surrounding the portion of said carrying bushing including said balls, said sleeve portion having means defining an inwardly facing conical surface with the larger diameter thereof being toward said nut, and
• spring means extending between said locking and carrying bushings for urging said carrying bushing away from said nut.