Futter

摘要

An arbor 1 having an axis of rotation 2 comprises a body member 3 having end 4 with flats so that it may be drivably secured in a spindle or chuck of a machine or machine tool. The body member 3 has a co-axial socket 5 provided at its opposite, cutting end 6 to receive a shank of a rotary cutter (not shown), the shank having, in the conventional manner, at least one flat. The arbor 1, further comprises a collar 7 carried at the cutting end 6, which collar 7 is biassed by a torsion spring 8 to an active position and is manually rotatable, within limits, against the spring bias, to an inactive position. A cam surface 9 is provided internally of the collar 7 and a segmental key 10 which is biassed radially outwardly by a pair of coil compression springs 11 to a cutter release position, has a flat, abutment surface 12, and an opposed, curved, displacement surface 13 engageable by the cam surface 9, and is also carried by the cutting end of the arbor, which key 10 is upon suitable manual rotation of the collar permitted to be displaced under its spring bias to the cutter release position, in which the key 10 is clear of the socket 5 to permit insertion, or removal, of a shank of a cutter into, or from, the socket. Upon manual release of the collar 7 permitting rotation of the collar under its spring bias, to an active position, at least the abutment surface 12 of the key 10 penetrates a portion of the socket 5 to engage a, or the, flat of an inserted cutter shank, with the cam surface 9 of the collar maintaining engagement with the displacement surface 13 of the key 10 to maintain the key 10 in its active position.