A support mechanism (20) for mounting a wheelchair back to a wheelchair post including at least one generally horizontally extending support pin (30), the support mechanism (20) comprising a hanger arm (24) having a downwardly opening hook (26) defining an upper support point and a self-locking latch (34) pivotally mounting to the hanger arm (24), the latch defining a locking notch (40) and a stop notch (42), the latch (34) being pivotal between a locked position in which the latch locking notch (40) and the hook (26) define a substantially closed hole around the support pin (30) and an unlocked position in which the pin (30) is seated in the stop notch (42) such that the latch (34) is secured open so the hanger arm hook (26) can be connected to or removed from the wheelchair post support pin (30) the latch (34) is shaped and weighted such that the latch can be moved to the locked position under the force of gravity.
