Lock mechanism for folding leg

A lock system releasably locking a first component, pivotally coupled along a pivot axis to a second component, in a plurality of positions fixed relative to the second component, wherein the second component comprises a substantially flat surface having a surface plane. the lock system comprising:

• (a) a first engaging mechanism fixed to the first component and aligned with the pivot axis such that the first engaging mechanism rotates in a rotation plane substantially perpendicular to the pivot axis when the first component is pivoted relative to the second component;
• (b) a second engaging mechanism pivotally mounted to the second component, wherein the second engaging mechanism is movable between an engaged position and a disengaged position;
• (c) wherein in the engaged position the second engaging mechanism fixedly engages with the first engaging mechanism, preventing the first component from pivoting relative to the second component, and wherein in the disengaged position the second engaging mechanism is removed from the first engaging mechanism such that the first component is free to pivot relative to the second component;
• (d) wherein the first engaging mechanism comprises a plurality of substantially flat sides which are substantially perpendicular to the plane of rotation;
• (e) wherein the first engaging mechanism is spaced from the flat surface such that when the first component is pivoted to align one of the flat sides of the first engaging mechanism substantially parallel to the flat surface, a gap is formed between the surface and said one side;
• and
• (f) wherein said second engaging mechanism is configured to substantially fill the gap. when the second engaging mechanism is in the engaged position.