Rotation braking device

A rotation braking device that is configured to be attached between a pair of members configured to rotate relative to each other and that is configured to apply a braking force when the other member rotates in a predetermined direction with respect to one member, the rotation braking device comprising:

• a braking member including a coupling member that is coupled to the one member and a first rotation member configured to rotate with respect to the coupling member via a rotation support portion, and configured to generate the braking force when the first rotation member rotates with respect to the coupling member;
• a second rotation member coaxially and rotatably mounted on the braking member via the rotation support portion;
• and
• a swing rotation member coupled to the other member, swingably supported with respect to the second rotation member via a swing support portion, and disposed on an outer periphery or an inner periphery of the first rotation member, wherein
• the first rotation member includes a first engaging portion configured to engage with the swing rotation member,
• the swing rotation member includes a second engaging portion configured to engage with the first engaging portion in a connectable and separable manner,
• a swing direction of the swing rotation member is to change depending on a rotation direction of the other member,
• when the other member rotates in the predetermined direction with respect to the one member, the swing rotation member swings in a direction in which the second engaging portion engages with the first engaging portion, and the first rotation member and the swing rotation member integrally rotate, and
• when the other member rotates in a direction opposite to the predetermined direction with respect to the one member, the swing rotation member swings in a direction in which the second engaging portion is separated from the first engaging portion, and the swing rotation member idles with respect to the first rotation member.