Trigger activated device for adjusting the inclination of a back frame of a wheelchair

Claim 1

A trigger activated device for adjusting inclination of a back frame of a wheelchair, comprising a pair of adjusting assemblies provided on each of two sides of said back frame, each said adjusting assemblies comprising: a horizontally disposed support with one end thereof fixed to a rear portion of a seat frame of the wheelchair, a first U-shaped prop extending upwardly from said support adjacent to said fixed end of said support; a back member being pivotally mounted on said first U-shaped prop at first end thereof by means of a pin located at an upper portion of said first U-shaped prop and transverse to a length of said support, a second U-shaped prop being attached to said back member at a lower portion thereof, a threaded bar being pivotally attached to said second U-shaped prop at a first end thereof; a handgrip being attached to an upper portion of said back member; a T-shaped hollow tube having a lug formed at one end thereof, said T-shaped hollow tube comprising a first section formed with a second section protuding from a middle portion of said first section, said T-shaped hollow tube being pivotally mounted to a free end of said support via said lug, said threaded bar passing through said first section of said T-shaped hollow tube, an end cap being provided at a free end of said second section of said T-shaped hollow tube, an engaging block having serrations provided at a first end thereof being provided in said second section, said serrations engaging with threads of said threaded bar, a second end of said engaging block being attached to a first end of a cable penetrating said end cap, a return spring being provided between said end cap and said second end of said engaging block; and a trigger means being disposed under said handgrip, a second end of said cable being attached to said trigger means, said serrations of said engaging block being actuated to disengage from said threaded bar via said cable such that said back member is pivotable during triggering of said means such that said return spring is compressed by said engaging block, when said trigger means is released, said serrations of said engaging block return to their original positions to engage with and fix said threaded bar by means of said return spring.