JPH05293143

PURPOSE:To provide thwe ascending/descending device which is compact, high in its rigidity, and also, inexpensive, and morevoer, can increase an ascending/ descending speed of a bed. CONSTITUTION:This ascending/descending device is provided with a two-stage parallel link mechanism 16 formed by connecting mutually the lower parallel link mechanism 14 attached to the upper part of a base 13 and the upper parallel link mechanism 12 attached to the lower part of an ascending/descending base 11 by a connecting mechanism 15, and a driving mechanism 17 which can allow the ascending/descending base 11 to ascend and descend by driving the two-stage parallel link mechanism 16. Also, this device is constituted so that the upper parallel link mechanism 12 and the lower parallel link mechanism 14 are provided with the upper link members 18a, 18b and the lower link members 20a, 20b, respectively, and the connecting mechanism 15 can engage mutually the upper gears 22a, 22b fixed to the upper link members 18a, 18b and the lower gears 23a, 23b fixed to the lower link members 20a, 20b so that one of the gears does not rotate around the rotary shaft of the other gear.