An external force absorbing device is provided which can absorb external force applied to a driven member. In this external force absorbing device 9, a driven member 3 is supported by a support member 70 rotatably about an axis L3. This external force absorbing device 9 is provided with a first biasing member 78 which rotates the driven member 3 in one direction about the axis L3, a contact unit 92 which contacts the driven member 3 to prevent rotation in one direction about the axis L3, a second biasing member 98 which biases the contact unit 92 towards the driven member 3 with a biasing force greater than the biasing force of the first biasing member 78, and a stopper 723 which prevents displacement of the contact unit 92 towards the driven member 3. Thus, when an external force rotating the driven member 3 about the axis L3 is applied, it is possible to absorb that external force by means of the first biasing member 78 and the second biasing member 98. Further, when the external force is removed, the driven member 3 automatically returns to the original orientation.