Patent ID: 8348205

Claim:
An expandable armrest of wheel chair, comprising: a fixed part having a first pivotal portion which includes a first pivotal hole, a shaft inserted into the first pivotal hole, the first pivotal portion having an engaging hole and a protrusion located beside the engaging hole, the protrusion having an inclined surface; a movable part pivotably connected to the first pivotal portion of the fixed part and having a second pivotal portion which includes a second pivotal hole and a through hole, the second pivotal portion having two slots defined therein, a first transverse hole and a second transverse hole defined in the second pivotal portion; a slide member slidably inserted into the slots and connected with a resilient member, the resilient member having a first hook and a second hook, the first hook hooked to the movable part and the second hook hooked to the slide member, the slide member having an inclined hole which is located corresponding to the first and second transverse holes, and an engaging member engaged with the inclined hole of the slide member and having a first end and a second end, the first end movably engaged with the first transverse hole and the second end movably engaged with the second transverse hole, a trace that the engaging member moves in the inclined hole constantly intersecting a trace that the first end moves in the first transverse hole and a trace that the second end moves in the second transverse hole, the engaging member having a bar which is perpendicular to the first and second ends, the bar extending out from the through hole and engaged with the engaging hole of the fixed part.