Protective element

Patent metadata

Field	Value
Publication number	US-12537156-B2
Application number	US-202117925133-A
Country	US
Kind code	B2
Filing date	May 26, 2021
Priority date	May 29, 2020
Publication date	Jan 27, 2026
Grant date	Jan 27, 2026

Abstract

A protective element includes a fuse element, a movable member, a concave member, and a press. The fuse member includes, a first end, a second end, and a cut part positioned between the first end and the second end. The fuse element is energized in a first direction from the first end to the second end. The movable member and the concave member are disposed facing each other such that the cut part is interposed therebetween. The press applies a force to the movable member in a pressing direction in which a distance between the movable member and the concave member shortens. At a temperature at or above a softening temperature of the fuse element, the cut part is cut by the force of the press.

First claim

The invention claimed is:

1 . A protective element, comprising:
a fuse element comprising a first end, a second end, and a cut part positioned between the first end and the second end, the fuse element being energized in a first direction from the first end to the second end; a movable member and a concave member disposed facing each other such that the cut part is interposed therebetween; a press to apply a force to the movable member in a pressing direction in which a distance between the movable member and the concave member shortens; a heating member comprising a resistor, having a plate shape, and disposed either contacting or near the cut part on a press side or a concave member side of the fuse element; and an electrical supply member connected to the resistor, the resistor of the heating member being heated by being energized through the electrical supply member, wherein the heating member is configured to be energized to directly heat the fuse element to a temperature at or above a softening temperature of the fuse element such that the cut part of the fuse element is softened and the force of the press cuts the cut part of the fuse element and a connection between the resistor and the electrical supply member.

2 . The protective element according to claim 1 , wherein a width of the cut part in a second direction of the fuse element is narrower than a width of a part other than the cut part in the second direction of the fuse element, the second direction being orthogonal to the first direction.

3 . The protective element according to claim 1 , wherein the cut part is disposed in a concave portion of the concave member in a plan view and is disposed at a position near an inner surface of the concave portion in the plan view, and
a length in a second direction, which is orthogonal to the first direction, of the concave portion is longer than a length in the second direction of the cut part.

4 . The protective element according to claim 1 , wherein the heating member is disposed inside a concave portion of the concave member in a plan view.

5 . The protective element according to claim 4 , wherein a length in the first direction of the heating member is shorter than a length of the concave portion in a third direction, the third direction being orthogonal to the first direction and a second direction orthogonal to the first direction.

6 . The protective element according to claim 1 , wherein the fuse element is a laminated body which comprises:
an inner layer comprising a first metal; and an outer layer disposed on an outer side of the laminated body compared to the inner layer and comprising a second metal, the second metal having a higher melting point than the first metal.

7 . The protective element according to claim 6 , wherein the first metal is composed of Sn or a metal in which Sn is a primary component thereof, and the second metal is composed of Ag or Cu or a metal in which Ag or Cu is a primary component thereof.

8 . The protective element according to claim 1 , wherein the press is a spring.

9 . The protective element according to claim 8 , wherein the spring has a conical shape and a side having a small diameter of the conical shape faces toward the cut part.

10 . The protective element according to claim 1 , wherein the movable member has a convex portion disposed at a position in which at least a portion of an area inside the concave portion is overlapped with an outer periphery of the convex portion in a plan view,
and the convex portion is inserted into the concave portion in a state in which the cut part is cut.

11 . The protective element according to claim 1 , further comprising: a first terminal electrically connected to the first end; and a second terminal electrically connected to the second end.

12 . The protective element according to claim 1 , further comprising:
a third terminal connected to the electrical supply member; and optionally a fourth terminal connected to the electrical supply member, wherein the heating member is electrically connected to the third terminal or to the third terminal and the fourth terminal via the electrical supply member, and the resistor of the heating member is heated by being energized through the electrical supply member.

13 . The protective element according to claim 1 , further comprising a case composed of a plurality of members in which at least the fuse element, the movable member, a concave portion of the concave member, and the press are housed,
wherein the press is housed within the case in a state in which the force is applied to the movable member in the pressing direction in which the movable member and the concave member shortens.

14 . The protective element according to claim 13 , wherein one member of the case comprises a housing part, the housing part being integrally formed, using the same material, from a first inner wall surface and a second inner wall surface that face each other in the pressing direction and a side wall surface connecting the first inner wall surface and the second inner wall surface,
the housing part supporting and holding stress in the case generated by the press in a staple shape by the first inner wall surface, the side wall surface, and the second inner wall surface in a state in which the fuse element is uncut.

15 . The protective element according to claim 13 , wherein material of at least one of the concave member and the case comprises nylon or ceramic.

16 . The protective element according to claim 1 , wherein the cut part is disposed in a concave portion of the concave member in the plan view and is disposed at the position near an inner surface of the concave portion in the plan view,
the movable member has a convex portion disposed at the position in which at least a portion of an area inside the concave portion is overlapped with an outer periphery of the convex portion and in which the convex portion is overlapped with a portion of the cut part, in the plan view, and in a state in which the cut part is cut, the convex portion is inserted into the concave portion and a portion of the fuse element is bent so as to be housed within the concave portion.

17 . The protective element according to claim 1 , wherein the heating member is disposed contacting the cut part on the press side or the concave member side of the fuse element, and in a state in which the cut part is cut, the heating member is in an unbroken state and a part of the fuse element is stored in the concave portion together with the heating member.

Assignees

• Dexerials Corp

Inventors

• Wada Yutaka
• Yoneda Yoshihiro

Classifications

• H01H85/055

  Fusible members · CPC title

• H01H37/00

  Thermally-actuated switches · CPC title

• H01H85/0039 Primary

  Means for influencing the rupture process of the fusible element · CPC title

• H01H37/76

  Contact member actuated by melting of fusible material, actuated due to burning of combustible material or due to explosion of explosive material · CPC title

• H01H85/0047

  Heating means · CPC title