US Patent 9987179 Adjustable wheelchair arrangements

An adjustable wheelchair includes a base frame having a first guide portion defining a first arcuate channel, and a seat frame having a second guide portion defining a second arcuate channel confronting the first arcuate channel. A first bearing assembly is secured to a front end of the first arcuate channel and extends into bearing engagement with the second arcuate channel. A rear bearing assembly is secured to a rear end of the second arcuate channel and extends into bearing engagement with the first arcuate channel. The seat frame is slideable in an arcuate path defined by the first and second arcuate channels for adjustment of a tilt angle of the seat frame with respect to the base frame.