Hammer drill with rapid chuck changing mechanism - has torque transmitted by balls which can be extracted radially by turning outside locking ring

摘要

The end (8) of the chuck (13) fits into the driving sleeve (4) of the hammer drill. Inside the sleeve and impacting on the drill shank (28) are the strikers (5,6). The driving torque is transmitted to the chuck by two diametrically opposed balls (11) which are contained in matching radial holes (10) and (12) in the end (8) of the chuck and the driving sleeve (4) of the hammer drill. - The balls are retained by a locking ring (14) encircling the driving sleeve. When the chuck is to be removed the locking ring is held by a pin inserted through a hole in the casing sleeve (22) and the chuck turned until the balls (11) can escape through apertures in the locking ring and casing sleeve. The chuck can then be easily withdrawn. The procedure is reversed to secure a new chuck.