To surely prohibit the movement of the other end of a mainspring and to obtain a music box having good tone by forming a contact part for prohibiting the movement of the other end of the mainspring held engaged with an engaging part toward the outer direction of a barrel drum.
The outside end 2b which is the other end of the mainspring 2 projects outward of a mainspring housing section and constricted parts 49 are formed. The constricted parts 49 are hooked and stopped to the engaging parts 50 which are formed at a case 8 and a frame 1 and are arranged on the frame 1. A barrier wall 55 as the contact part to be pressed to the front end of the outside end 2b of the mainspring 2 is extended and formed at a pedestal 57 in a direction orthogonal with the side plate mounted with a diaphragm. Then, even if the friction force between the mainspring 2 and the mainspring housing part changes, the movement of the outside end 2b in the outward direction of the barrel drum is surely limited by the barrier wall 55 and the release of the energized mainspring 2 is smoothly effected. In addition, the striking sounds with the engaging parts by the movement of the outside end 2b are decreased and noise is lowered.
TAKEMURA JUNICHI
ORII MAKOTO
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