Patent ID: 8870147

Claim:
A track assembly comprising: a track defining a first axis and having formed therein a succession of apertures uniformly spaced along a portion of said track; a slide mechanism slidably attached to said track for movement relative to said track along said first axis; and a lock mechanism mounted to said slide mechanism and operable between a locked state preventing movement of said slide mechanism relative to said track and an unlocked state permitting movement of said slide mechanism relative to said track, said lock mechanism comprising: a housing, and three lock plates positioned alongside one another in said housing and independently movable along a second axis perpendicular to said first axis between an engaged position and a disengaged position, each of said three lock plates having a plurality of posts correspondingly spaced relative to the spacing of said apertures, the posts of each of said three lock plates being offset in a direction of said first axis relative to the posts of another two of said three lock plates when positioned in said housing, wherein in said engaged position the plurality of posts of a lock plate engage the apertures in said track and in said disengaged position the plurality of posts of a lock plate do not engage the apertures in said track, and further wherein in the locked state of said lock mechanism two of said lock plates are in said engaged position and one of said lock plates is in said disengaged position.