Thermal fuse and method for its activation

A thermal fuse, comprising:

• a leaf spring formed of a narrow sheet metal strip;
• said leaf spring having ends and at least two contact points at said ends, at least one of said contact points being a soldering point for connection with corresponding circuit contacts of a circuit substrate;
• said leaf spring having at least one spring arm interconnecting said contact points;
• said at least one spring arm having a roof-shaped deformation in the vicinity of one of said contact points;
• said at least one spring arm having a flat and elongated spring segment with a transition adjoining said deformation and a transition extending to the other of said contact points, said spring segment being bending resistant in the vicinities of said transitions, for transforming a compressive deformation applied to said roof-shaped deformation into a lateral movement and into an arching of said spring segment, with both of said ends of said leaf spring attached to the circuit substrate without pretensioning;
• and
• said spring segment having a given cross section, and said roof-shaped deformation having a cross section being reduced at least relative to said given cross section.

A thermal fuse, comprising:

• a leaf spring formed of a narrow sheet metal strip;
• said leaf spring having ends and at least two contact points at said ends, at least one of said contact points being a soldering point for connection with corresponding circuit contacts of a circuit substrate;
• said leaf spring having at least one spring arm interconnecting said contact points;
• said at least one spring arm having a roof-shaped deformation in the vicinity of one of said contact points;
• said at least one spring arm having a flat and elongated spring segment with a transition adjoining said deformation and a transition extending to the other of said contact points, said spring segment being bending resistant in the vicinities of said transitions, for transforming a compressive deformation applied to said roof-shaped deformation into a lateral movement and into an arching of said spring segment, with both of said ends of said leaf spring attached to the circuit substrate without pretensioning;
• and
• said spring segment being stiffened by a crimp in the vicinity of said transition to the other of said contact points.

A thermal fuse, comprising:

• a leaf spring formed of a narrow sheet metal strip;
• said leaf spring having ends and at least two contact points at said ends, at least one of said contact points being a soldering point for connection with corresponding circuit contacts of a circuit substrate;
• said leaf spring having at least one spring arm interconnecting said contact points;
• said at least one spring arm having a roof-shaped deformation in the vicinity of one of said contact points;
• said at least one spring arm having a flat and elongated spring segment with a transition adjoining said deformation and a transition extending to the other of said contact points, said spring segment being bending resistant in the vicinities of said transitions, for transforming a compressive deformation applied to said roof-shaped deformation into a lateral movement and into an arching of said spring segment, with both of said ends of said leaf spring attached to the circuit substrate without pretensioning;
• and said spring segment tapering toward the other of said contact points.

A thermal fuse, comprising:

• a leaf spring formed of a narrow sheet metal strip;
• said leaf spring having ends and at least two contact points at said ends, at least one of said contact points being a soldering point for connection with corresponding circuit contacts of a circuit substrate;
• said leaf spring having at least one spring arm interconnecting said contact points;
• said at least one spring arm having a roof-shaped deformation in the vicinity of one of said contact points;
• said at least one spring arm having a flat and elongated spring segment with a transition adjoining said deformation and a transition extending to the other of said contact points, said spring segment being bending resistant in the vicinities of said transitions, for transforming a compressive deformation applied to said roof-shaped deformation into a lateral movement and into an arching of said spring segment, with both of said ends of said leaf spring attached to the circuit substrate without pretensioning;
• and
• one of said at least two contact points being disposed at one of said ends of said leaf spring and being a contact tab spanning two separate circuit contacts of the circuit substrate.

A thermal fuse, comprising:

• a leaf spring formed of a narrow sheet metal strip;
• said leaf spring having ends and at least two contact points at said ends, at least one of said contact points being a soldering point for connection with corresponding circuit contacts of a circuit substrate;
• said leaf spring having at least one spring arm interconnecting said contact points;
• said at least one spring arm having a roof-shaped deformation in the vicinity of one of said contact points;
• said at least one spring arm having a flat and elongated spring segment with a transition adjoining said deformation and a transition extending to the other of said contact points, said spring segment being bending resistant in the vicinities of said transitions, for transforming a compressive deformation applied to said roof-shaped deformation into a lateral movement and into an arching of said spring segment, with both of said ends of said leaf spring attached to the circuit substrate without pretensioning;
• and
• said leaf spring having two parallel spring arms, each of said spring arms being a respective one of said contact points separately disposed thereon at one of said ends of said leaf spring, and said spring arms being joined together at the other of said ends of said leaf spring.

A thermal fuse, comprising:

• a leaf spring formed of a narrow sheet metal strip;
• said leaf spring having ends and at least two contact points at said ends, at least one of said contact points being a soldering point for connection with corresponding circuit contacts of a circuit substrate;
• said leaf spring having at least one spring arm interconnecting said contact points;
• said at least one spring arm having a roof-shaped deformation in the vicinity of one of said contact points;
• said at least one spring arm having a flat and elongated spring segment with a transition adjoining said deformation and a transition extending to the other of said contact points, said spring segment being bending resistant in the vicinities of said transitions, for transforming a compressive deformation applied to said roof-shaped deformation into a lateral movement and into an arching of said spring segment, with both of said ends of said leaf spring attached to the circuit substrate without pretensioning;
• and
• one of said ends of said leaf spring being additionally fastened to the circuit substrate.