GB589168A - Improvements in or relating to chucks - Google Patents

Abstract

589,168. Chucks. AKTIEBOLAGET F. RAMSTROM, and AXELSSON, J. A. March 16, 1945, No. 6652. [Class 83 (iii)] In a chuck for drills &c., operable whilst rotating, three interlocking jaws 8 are actuated by a conical portion 7 of the sleeve 1 which is moved axially on the body 3 by rotation on the thread 5. A torsion spring 6 is attached at its ends to the body and sleeve and tends to rotate the sleeve into the lowermost or open position. In operation, with the chuck rotating, a ring 19, with two skirts 20 and 21 and rotatable on the body, is braked by hand, causing the skirt 20 to move rollers 25 to the unlocking position in cam surfaces 26, Fig. 2, on a ring 27 attached to the body and allowing the spring 6 to move the sleeve 1 to the lowermost position ; a bentup, resilient ring 33 minimizes the impact. After inserting the tool between the jaws, the sleeve 1 is also braked causing it to move upwardly and close the jaws. When the tool is gripped, the sleeve 1 and ring 19 are released and a torsion spring 28 rotates the ring 19 so that the skirt 20 wedges the rollers 25 between the cam surfaces 26 and the sleeve 1, thereby locking the sleeve in its adjusted position. A pin 23 on the body limits rotation of the ring 19. The spring 6 may act on the sleeve 1 by axial pressure only or may be omitted if the pitch of thread 5 is sufficiently coarse to allow the sleeve to descend under gravity. With increased axial working pressure, the tool bears on the valve-shaped member 14 and imparts a downward pressure to the upper surfaces of the jaws 8 through balls 18 and a pressure ring 9, thereby increasing the gripping action of the jaws.