Thermodynamic overload relay

An engagement hole (21) is formed in the side surface of the housing (12) in the width direction, a protruding piece (22) protruding toward the housing (12) side is formed in the cover (13), and the tip (23) of the protruding piece (22) is fitted into the engagement hole (21) from the inside. The restoring rod (34) has a recess (55) formed in the outer peripheral surface within a predetermined range in the depth direction and the circumferential direction, and prevents the tip section (23) from being pushed inward by the outer peripheral surface facing the inner side of the protruding piece (22) when the restoring rod (34) is located at either the initial position or the automatic restoring position. In addition, in the manual reset position, the front end portion (23) is allowed to be pushed inwards by the concave portion (55) facing the inner side of the protruding piece (22). 壳体(12)在宽度方向的侧面形成有卡合孔(21)，罩(13)形成有向壳体(12)侧突出的突出片(22)，突出片(22)的前端部(23)从内侧嵌合于卡合孔(21)。复位棒(34)在外周面中的进深方向和周向的预先决定的范围内形成有凹部(55)，在位于初始位置和自动复位