Cutting tool

A cutting tool comprising a holder and a cutting insert, having a first through bore, mounted in an insert receiving pocket of the holder, the insert receiving pocket has a base wall and at least one side wall, a second bore of the holder extends downwardly from the base wall, a third bore of the holder extends rearwardly from the second bore and opens into a fourth bore of the holder, the fourth bore is slanted at a first slant angle (α) with respect to the third bore;

• a locking pin inserted in the second bore protrudes upwardly into the first through bore, the locking pin has an upper portion and a lower portion having a front side and a rear side, a protrusion extends rearwardly from the upper portion, the lower portion has a rearwardly facing groove that is substantially co-aligned with the third bore, a forward end of the groove is substantially closer to the front side of the lower portion than to the rear side of the lower portion;
• a plunger received in the third bore, a forward portion of the plunger protrudes forwardly into the second bore and is in contact engagement with a forward portion of the groove, a rear portion of the plunger protrudes rearwardly into the fourth bore and has a first engagement surface transversely directed to a first axis (A) of the plunger;
• a clamping member engaged in the fourth bore, the clamping member has a second engagement surface in contact engagement with the first engagement surface;
• in a first position of the cutting tool, the protrusion of the locking pin is spaced forwardly from a retaining portion at a rear portion of the first through bore of the cutting insert;
• in a second position of the cutting tool, the second engagement surface of the clamping member applies pressure to the first engagement surface of the plunger thereby urging forwardly the forward portion of the plunger against the forward portion of the groove of the locking pin, a first contact point in an upper section of the lower portion of the locking pin is pressed to a forward portion of the second bore and the protrusion of the locking pin presses downwardly and rearwardly the retaining portion at the rear portion of the first through bore of the cutting insert thereby securely retaining the cutting insert in the insert retaining pocket against the base wall and the at least one side wall of the insert receiving pocket.