Extension and contraction device

An extension and contraction device comprising:

• a tape having an elasticity;
• and
• a tape driving device configured to perform winding up of the tape and delivery of the tape, wherein
• the tape driving device has:
• a reel around which the tape is wound in a roll shape;
• a motive-power source configured to perform the winding up of the tape onto the reel and the delivery of the tape from the reel;
• a band member in which a first end side is constrained and a second end side is a movable free end, the band member being provided along an outer circumferential surface of the tape wound around the reel in the roll shape, and the band member being configured to press the tape against the reel;
• tension adjusting mechanism configured to adjust tension of the band member by regulating a position of the free end of the band member;
• a housing configured to accommodate the reel and the motive-power source, the housing being provided with an entrance and exit of the tape;
• a support body configured to support the reel;
• and
• a guide part provided at the housing, the guide part being configured to guide movement of the support body, wherein
• the support body is configured to be moved relative to the housing by being guided by the guide part as the reel is rotated.