Protective element

• US 7,286,037 B2
• Filed: 12/05/2003
• Issued: 10/23/2007
• Est. Priority Date: 12/27/2002
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Chemical & Information Device Corporation (Sony Group Corp.), Sony Corporation (Sony Group Corp.)
• Inventors: Furuuchi, Yuji
• Primary Examiner(s): Vortman; Anatoly
• Application Number:
  US10/537,908
• Publication Number:
  US 20060028314A1
• Time in Patent Office: 1,418 Days
• Field of Search: 337/290, 337/296, 337/159, 337/416, 337/4, 296/23, 219/517
• US Class Current: 337/290
• CPC Class Codes: H01H 2085/466 with remote controlled forced fusing
• CPC Class Codes: H01H 85/046 Fuses formed as printed circuits

Abstract

A protective element with improved spherical segmentation performance during the melting of a low-melting metal member, has a heat-generating member and a low-melting metal member on a substrate, in which the low-melting metal member is heated and blown out by the heat generated by the heat-generating member. There is a region in which the low-melting metal member is suspended over the underlying base (such as an insulating layer), and when S (μm²) is the surface area of a lateral cross section of the low-melting metal member 4 between a pair of low-melting metal member electrodes 3a and 3b or 3b and 3c sandwiching the region, and H (μm) is the height at which the suspended region is suspended, then the relationship H/S≧5×10⁻⁵ is satisfied. It is preferable here that the upper surfaces of both of the pair of low-melting metal member electrodes protrude beyond the upper surface of the underlying insulating layer.

Claims

1. A protective element, comprising a heat-generating member and a low-melting metal member on a substrate, in which the low-melting metal member is blown out by the heat generated by the heat-generating member,

wherein there is provided a region in which the low-melting metal member is suspended over a underlying base, and when S (μ

m²) is the surface area of a lateral cross section of the low-melting metal member between a pair of low-melting metal member electrodes sandwiching said region, and H (μ

m) is the height at which the suspended region is suspended, then H/S≧

5×

10<sup>−

5</sup>.

2. The protective element according to claim 1, wherein the upper surfaces of both of the pair of low-melting metal member electrodes protrude beyond the upper surface of an insulating layer which is the underlying base.

3. The protective element according to claim 1, wherein there is provided a height differential between the upper surfaces of the pair of low-melting metal member electrodes, and the low-melting metal member is inclined between said pair of low-melting metal member electrodes.

4. The protective element according to claim 1, wherein an insulating spacer is provided between the pair of low-melting metal member electrodes, and the upper surface of said spacer protrudes beyond the upper surfaces of the pair of low-melting metal member electrodes.