Patent ID: 7471476

Claim:
A barrel assembly comprising: a stationary barrel surrounding an axis and having a first surface, a second surface opposite to said first surface in radial directions relative to the axis, and a guide slot formed through said first and second surfaces and extending parallel to the axis; a first barrel component engaging sleevingly said stationary barrel, and having a third surface that faces said first surface of said stationary barrel; a second barrel component engaging sleevingly said stationary barrel, and having a fourth surface that faces said second surface of said stationary barrel, and a cam slot that is formed in said fourth surface, that extends around the axis, and that is cooperatively defined by a first slide surface connected to said fourth surface, a second slide surface connected to said fourth surface and confronting said first slide surface, a first abutting portion connected to said first slide surface opposite to said fourth surface, and a second abutting portion connected to said second slide surface opposite to said fourth surface; and a coupling pin extending radially from said first barrel component through said stationary barrel to said second barrel component, and having a connecting section connected to said third surface of said first barrel component, a guide section extending from said connecting section and through said guide slot in said stationary barrel so as to be guided thereby, a retaining section extending from said guide section and slidable along said first and second slide surfaces of said cam slot in said second barrel component, and a reinforcing section extending from said retaining section and extending between said first and second abutting portions of said cam slot.