| 摘要 |
PROBLEM TO BE SOLVED: To prevent or relieve the dropping of the waist when a user raises an upper half body by actuating the upper half body supporting frame to rise. SOLUTION: A lower half body mattress 4 fixed to a lower half body supporting frame 2 and an upper half body mattress 5 fixed to the upper half body supporting frame 3 are separated from each other and the end 4a of the lower half body mattress 4 on the upper half body mattress 5 side deviates more to the head side than a virtual axial center O which is the center of rotation of the luffing operation of the upper half body supporting frame 3. The weight of the upper half body A1 of the user A in the rising state, therefore, acts on the position apart from the end 4a of the lower half body mattress 4 and the supporting area of the weight at the lower half body mattress 4 increases. |
