A support assembly according to one embodiment of the present invention includes a support rotatably disposed with respect to a frame, a repetition lever rotatably connected to the support, an spring element supported by a support portion fixed to the support, the spring element which provides a rotational force to the repetition lever, and a contact portion between the repetition lever and the spring element, wherein a rotating portion of the repetition lever is provided with respect to the support portion on a side opposite to the contact portion between the repetition lever and the spring element.