Abstract: A thermal fuse includes a leaf spring formed of a narrow sheet metal strip. The leaf spring has ends and at least two contact points at the ends. At least one of the contact points is a soldering point for connection with corresponding circuit contacts of a circuit substrate. The leaf spring has at least one spring arm interconnecting the contact points. The spring arm has a roof-shaped deformation in the vicinity of one contact point. The spring arm has a flat and elongated spring segment with a transition adjoining the deformation and a transition extending to the other contact point. The spring segment is bending resistant in the vicinities of the transitions, for transforming a compressive deformation applied to the roof-shaped deformation into a lateral movement and into an arching of the spring segment, with both ends of the leaf spring attached to the circuit substrate without pretensioning.