Solderless surface mount fuse

• US 8,937,524 B2
• Filed: 03/25/2009
• Issued: 01/20/2015
• Est. Priority Date: 03/25/2009
• Status: Active Grant

• Current Assignee: Littelfuse Incorporated
• Original Assignee: Littelfuse Incorporated
• Inventors: de Leon, Conrado, Dietsch, Gordon T., Olan, Edgardo, Semana, John Emannuel, Song, John, Whitney, Stephen J.
• Primary Examiner(s): Vortman, Anatoly
• Application Number:
  US12/410,596
• Publication Number:
  US 20100245025A1
• Time in Patent Office: 2,127 Days
• Field of Search: 337/290, 337/187, 337/159, 337/142, 296/23
• US Class Current: 337/290
• CPC Class Codes: H01H 2085/0412 specially adapted for being mounted on a printed circuit board
• CPC Class Codes: H01H 2085/0414 Surface mounted fuses
• CPC Class Codes: H01H 69/02 Manufacture of fuses
• CPC Class Codes: H01H 85/0418 with ferrule type end contacts
• CPC Class Codes: H01H 85/055 Fusible members
• CPC Class Codes: H01H 85/08 characterised by the shape or form of the fusible member
• CPC Class Codes: H01H 85/157 Ferrule-end contacts
• CPC Class Codes: H01H 85/165 Casings
• CPC Class Codes: H05K 3/3421 Leaded components
• CPC Class Codes: Y10T 29/49107 Fuse making

Abstract

A surface mount fuse in one embodiment includes an insulative body, first and second conductive and caps attached to the insulative body, each end cap defining an aperture, and a fuse element extending (i) through the insulative body and the apertures and (ii) along outside surfaces of the first and second conductive end caps in such a way that solder used to attach the first and second conductive end caps to an external medium also fastens the fuse element to the first and second end caps.

Claims

1. A surface mount fuse comprising:

an insulative body;

first and second conductive end caps attached to the insulative body, each end cap defining an aperture that extends through a wall of the end cap; and

a fuse element having a horizontal section extending through the insulative body and the apertures, the fuse element further including first bent sections connected to opposite ends of the horizontal section, the first bent sections extending from the apertures along an outer surface of the first and second conductive end caps to a bottom surface of the first and second conductive end caps, the fuse element further including second bent sections connected to the first bent sections, the second bent sections being parallel to the horizontal section and configured to attach the fuse element to pads on a printed circuit board, wherein the fuse element is secured in the insulative body and the first and second conductive end caps are secured to the insulative body by the first bent sections.

2. The surface mount fuse of claim 1, wherein the fuse element is one of a wire and a strip.

3. The surface mount fuse of claim 1, wherein the insulative housing is made of one of ceramic and glass, melamine or glass-epoxy composite.

4. The surface mount fuse of claim 1, wherein the second bent sections extend away from the first and second conductive end caps and the insulative body.

5. The surface mount fuse of claim 1, wherein solder used to attach the second bent sections to the pads on the printed circuit board also attached the first bent sections to the first and second conductive end caps.

6. A method of manufacturing a surface mount fuse comprising:

attaching first and second end caps to an insulative body, each of said first and second end caps defining an aperture that extends through a wall of the first and second end caps;

inserting a fuse element into the insulative body such that portions of the fuse element extend through the apertures, the portion of the fuse element in the insulative body being disposed in a first plane;

bending the portions of the fuse element that extend out of the apertures at a point near an outer surface of the first and second end caps to form first bent sections of the fuse element that extend along an outer surface of the first and second end caps; and

bending portions of the first bent sections of the fuse element at a point near a bottom surface of the first and second end caps to form second bent sections of the fuse element that extend in the first plane parallel to the portion of the fuse element in the insulative body, the second bent sections configured to attach the fuse element to pads on a printed circuit board,

wherein the fuse element is secured in the insulative body and the first and second end caps are secured to the insulative body by the first bent sections.

7. The method of claim 6, wherein the fuse element is inserted into the insulative body before the first and second end caps are secured to the insulative body.

8. The method of claim 6, further comprising crimping the fuse element between the insulative housing and the first and second conductive end caps.

9. The method of claim 6, wherein the fuse element is one of a wire and a strip.

10. The method of claim 6, wherein the insulative housing is made of one of ceramic and glass, melamine and glass-epoxy composite.

11. A surface mount fuse manufactured according to the method of claim 6.

12. The method of claim 6, wherein the second bent sections extend away from the first and second conductive end caps and the insulative body.

13. The method of claim 6, wherein solder used to attach the second bent sections to the pads on the printed circuit board also attached the first bent sections to the first and second conductive end caps.