Medical apparatus for standing aid

A medical apparatus for standing aid, comprising a crank rocker mechanism provided on at least one side of a backrest (4), a motor (7), a primary chain drive mechanism (8), and a secondary chain drive mechanism (10), wherein the crank rocker mechanism supports a trainee's body to perform sitting and rising movements, the backrest (4) provides the trainee with back support, the crank rocker mechanism comprising a crank mechanism (1), a triangular-shaped link age mechanism (2), and a rocker mechanism (3);

• where in a training process, the motor (7) rotates forward to drive the primary chain drive mechanism (8), the primary chain drive mechanism 8) drives the secondary chain drive mechanism (10), the secondary chain drive mechanism (10) drives the crank mechanisms (1) to rotate at a reduced speed, the triangular-shaped linkage mechanism (2) is then driven by the crank mechanisms (1) to correspondingly rotate, and the rocker mechanisms (3) follows the movement of the triangular-shaped linkage mechanism (2) to rotate, such that the backrest (4) is driven by the triangular-shaped linkage mechanism (2) to move upwardly and the trainee stands up progressively with assistance from the backrest (4);
• after the trainee reaches a standard standing posture, the motor (7) starts to rotate in reverse, the crank mechanism (1) rotates downwardly slowly driven by the first chain drive mechanism (8) and the second drive chain mechanism (10), the triangular-shaped linkage mechanism (2) moves correspondingly to drive the backrest (4) to move downwardly, such that with assistance from the backrest (4), the trainee returns to a sitting posture from a standing posture progressively:
• the crank mechanism (1) being rotatably connected to the triangular-shaped linkage mechanism (2) such that an angle between a second driven link (BE) of the triangular-shaped linkage mechanism (2) and the crank mechanism (1) is always smaller than 90° , and the crank mechanism (1) driving the triangular-shaped linkage mechanism (2), the rocker mechanism (3) and the backrest (4) connected to the triangular-shaped linkage mechanism (2) to perform interactive movement repeatedly along a predetermined curved trajectory in response to a drive effect resulting from a driving force of a driving unit (100), so that the backrest (4) connected to the second driven link (BE) assists the trainee in standing up repeatedly by obliquely supporting the trainee's waist.