The stand-up unit (10) comprises a support (21), a stand-up frame (13), whichis articulated on the support (21) and has a seat carrier (23) carrying a seat (17),and a backrest carrier (25) carrying a backrest (19). Furthermore, a first leverparallelogram (27) is provided in order to maintain the backrest (19) uprightin any position. The backrest (19) can be displaced by the first lever parallelogram(27) by means of a rod (30), in order to ensure that no undesirable relative movementoccurs between the backrest (19) and the back of the user when getting up or sittingdown. A second lever parallelogram (29) controls the movement of the seat (17)when getting up and sitting down to ensure that no relative movement developsbetween the seat (17) and buttocks of the user. The stand-up unit may be providedwith a base to serve as a chair, particularly a therapy chair. The stand-up unit,however, may also serve as a stand-up wheelchair, when connected to an undercarriage.Spring joint elements (59, 61) support the standing up.
