TWI722862B

A displacement mechanism contains: a support rack, a sitting assembly, a slide rod, two fixing feet, a back, a first holding plate, a second holding plate, and an expandable sheet. The support rack includes a fixer having a post, a rolling stand having multiple first rollers, and a lifter. The sitting assembly includes a receiving orifice and a rotatable mounting. The slide rod includes an elongated hole for connecting the slide rod with the post. A respective foot includes a second roller. The back is disposed on a rear end of the sitting assembly. The first holding plate is mounted on a seat of a wheelchair, and the sitting assembly is slid between the fixer and the first holding plate. The second holding plate is connected on a seat of a car. The expandable sheet is disposed between the fixer and the second holding plate.