STEM RETAINER Russian patent published in 2010 - IPC B23B31/00 

FIELD: process engineering.

SUBSTANCE: invention relates to drilling devices, namely to drill arbors. Proposed device allows feeding coolant to drill bit without central core. Stem 30 can be detached from hole 2 in one move. Stem OD allows stem fitting into hole 2. Stem front end has concave section 31, while skewed section 33 is made around outer peripheral edge of stem rear end. Rear end 1B, on the side of rear end of hole 2 for stem fixation, has hole 3 for coolant feed. Hole 3 accommodates valve element 5. Seal 4 is arranged closer to front end than valve element 5. First sleeve 20 seats in stem hole so that is rear end stays in contact with front end of first sleeve 20 to allow it to move so that rear end of first sleeve 20 stays in contact with valve element 5 to allow it to be separated from sealing element 4 and in position wherein stem does not stay in contact with front end of first sleeve 20. Outer peripheral surface of first sleeve 20 has diametre equal to that of hole 2 to cause displacement of hooking element 15 radially outward from inner peripheral surface of hole 2.

EFFECT: controlled feed of coolant in case annular drill has no central core.

9 cl, 13 dwg