Platform of electric-movable bed for bedsore prevention capable of adjusting shaft according to user body type and method for controlling position change period thereof

A platform of an electric-movable bed capable a shaft comprising:

• a plate unit comprising a plurality of main plates rotatably provided to support a human body,
• a plurality of sub plates rotatably and hingedly coupled to the main plates, respectively, and a locking part provided between each main plate and each sub plate to enable or lock a rotation of each main plate or sub plate, the plate unit being configured to selectively rotate a corresponding portion to a position of a joint according to a user's body type;
• a first driving unit configured to tilt an upper part of the human body lying on the plate unit;
• and
• a second driving unit configured to tilt a lower part of the human body lying on the plate unit,
• wherein the locking part comprises, an upper locking body provided in a lateral surface of a main plate or a sub plate out of neighboring main or sub plates;
• a lower locking body rotatably provided under the other main or sub plate out of two neighboring main or sub plates, the lower locking body extended to a lower portion of the upper locking body;
• and a locking rod coupled to one of the upper and lower locking bodies, with being extended to be selectively fixed to the other one, the locking rod configured to selectively lock a rotation of the neighboring main or sub plates.