Temperature compensation-type balance, timepiece movement, mechanical timepiece and manufacturing method of temperature compensation-type balance

摘要

A temperature compensation-type balance includes a balance staff, and a balance wheel having a plurality of bimetal portions disposed in parallel to each other in a circumferential direction around a rotation axis of the balance staff. Connection members connect respective ones of the plurality of bimetal portions and the balance staff. Each bimetal portion is a layered body in which a first member and a second member are radially overlapped, and one end portion in the circumferential direction is a fixed end connected to a respective connection member and the other end portion in the circumferential direction is a free end. The first member is formed of a ceramic material, and the second member is formed of a metal material having a thermal expansion coefficient different from that of the first member.