A FUSE ELEMENT, A FUSE, A METHOD FOR PRODUCING A FUSE, SMD FUSE AND SMD CIRCUIT

• US 20170040136A1
• Filed: 12/23/2013
• Published: 02/09/2017
• Est. Priority Date: 12/23/2013
• Status: Active Grant

• Current Assignee: Schurter AG (Schurter Holding AG)
• Original Assignee: Schurter AG (Schurter Holding AG)
• Inventors: STRAUB, Peter, BLATTLER, Hans-Peter
• Granted Patent: US 10,192,705 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01H 69/02 Manufacture of fuses
• CPC Class Codes: H01H 85/0411 Miniature fuses
• CPC Class Codes: H01H 85/06 characterised by the fusible material H01H85/11 takes precedence
• CPC Class Codes: H01H 85/08 characterised by the shape or form of the fusible member
• CPC Class Codes: H01H 85/11 with applied local area of a metal which, on melting, forms a eutectic with the main material of the fusible member, i.e. M-effect devices
• CPC Class Codes: H01H 85/20 Bases for supporting the fuse; Separate parts thereof
• CPC Class Codes: H01H 85/205 Electric connections to contacts on the base

Abstract

The invention relates to a fuse element (12_1; 12_2), comprising two connecting contacts (24_1′, 24_1″; 24_2′, 24_2″) and an interposed conductive track (26_1; 26_2), wherein the conductive track (26_1; 26_2) has a reduced line-cross-section in relation to the connecting contacts (24_1′, 24_1″; 24_2′, 24_2″) at least in some sections, further comprising at least one overlay (16_1; 16_2′, 16_2″), wherein the fuse element (12_1; 12_2) and the overlay (16_1; 16_2′, 16_2″) each comprise materials which undergo diffusion when a predetermined ambient temperature is exceeded and when an electric current is conducted by the fuse element (12_1; 12_2). The invention further relates to a fuse (IO) having such a fuse element (12_1; 12_2) and a base support (14), wherein the fuse element (12_1; 12_2) is disposed on a surface of the base support (14).

Claims

1. A fuse element (12_1;

12_2), comprising two connecting contacts (24_1′

, 24_1″

;

24_2′

, 24_2″

) and an interposed conductive track (26_1;

26_2), wherein the conductive track (26_1;

26_2) has a reduced line cross-section in relation to the connecting contacts (24_1′

, 24_1″

;

24_2′

, 24_2″

) at least in some sections, further comprising at least one overlay (16_1;

16_2′

, 16_2″

), wherein the fuse element (12_1;

12_2) and the overlay (16_1;

16_2′

, 16_2″

) each comprise materials which undergo diffusion when a predetermined ambient temperature is exceeded and when an electric current is conducted by the fuse element (12_1;

12_2).

2. The fuse element (12_1;

12_2) according to claim 1, wherein the at least one overlay (16_1;

16_2′

, 16_2″

) is arranged at least in sections within the conductive track (26_1;

26_2).

3. The fuse element (12_1) according to claim 1, wherein the at least one overlay (16_1) is arranged within the conductive track (26_1) adjacent to one of the connecting contacts (24_1′

, 24_1″

) of the fuse element (12_1).

4. The fuse element (12_2) according to claim 1, wherein the line cross-section of the conductive track (26_2) increasingly converges step-by-step to the line cross-section of the connecting contacts (24_2′

, 24_2″

).

5. The fuse element (12_2) according to claim 4, wherein the at least one overlay (16_2′

, 16_2″

) is arranged at least in sections within the conductive track (26_2) in a region of the gradually increasing line cross-section.

6. The fuse element (12_2) according to claim 4, wherein the at least one overlay (16_2′

, 16_2″

) is arranged in a region of the conductive track (26_2) with a gradually increasing line cross-section adjacent to a section of the conductive track (26_2) with minimal line cross-section.

7. The fuse element (12_1;

12_2) according to claim 1, further comprising at least one recess (20_1;

20_2′

, 20_2″

) which is introduced into the conductive track (26_1;

26_2) and in which the at least one overlay (16_1;

16_2′

, 16_2″

) is arranged.

8. The fuse element (12_1;

12_2) according to claim 7, wherein the at least one recess (20_1;

20_2′

, 20_2″

) is oriented in a continuously transverse manner in relation to the longitudinal direction of the conductive track (26_1;

26_2).

9. The fuse element (12_1;

12_2) according to claim 1, wherein the material of the fuse element (12_1;

12_2) comprises copper and the material of the overlay (16_1;

16_2′

, 16_2″

) comprises tin.

10. The fuse (10), comprising at least one fuse element (12;

12′

, 12″

) according to claim 1 further comprising a base support (14) made of an electrically insulating material, wherein the fuse element (12;

12′

, 12″

) is arranged on a surface of the base support (14).

11. The fuse (10) according to claim 10, wherein the fuse element (12′

, 12″

) is arranged on opposite surfaces of the base support (14).

12. The fuse (10) according to claim 10, further comprising two base contacts (18′

, 18″

) which are each electrically connected to connecting contacts of the fuse elements (12′

, 12″

) which are opposite the base support (14).

13. The fuse (10) according to claim 10, wherein the base support (14) comprises a Rogers4000 material.

14. The fuse (10) according to claim 10, wherein the at least one fuse element (12;

12′

, 12″

) is coated with a protective lacquer (22;

22′

, 22″

), especially a protective polymer lacquer.

19. An SMD fuse, comprising a fuse (10) according to claim 10.

20. An SMD circuit, comprising an SMD fuse according to claim 19.

15. A method for producing a fuse (10), comprising the steps of:

providing at least one fuse element (12;

12′

, 12″

) having two connecting contacts (24, 24″

) and an interposed conductive track (26), such that the conductive track (26) has a reduced line cross-section in relation to the connecting contacts (24′

, 24″

) at least in some sections;

providing a base support (14);

providing the fuse element (12;

12′

, 12″

) with at least one overlay (16;

16′

, 16″

), wherein the fuse element (12;

12′

, 12″

) and the overlay (16;

16′

, 16″

) are each selected from materials which undergo diffusion when a predetermined ambient temperature is exceeded and when an electric current is conducted by the fuse element (12;

12′

, 12″

), and

arranging the at least one fuse element (12;

12′

, 12″

) on the base support (14).

16. The method according to claim 15, wherein the at least one overlay (16;

16′

, 16″

) is arranged at least in sections within the conductive track (26) of the fuse element (12;

12′

, 12″

).

17. The method according to claim 15, wherein the at least one overlay (16;

16′

, 16″

) is arranged within the conductive track (26) adjacent to one of the connecting contacts (24′

, 24″

) of the fuse element (12;

12′

, 12″

).

18. The method according to one of the claim 15, wherein the step of providing the fuse element (12;

12′

, 12″

) with the at least one overlay (16;

16′

, 16″

) comprises arranging the overlay (16;

16′

, 16″

) in at least one recess (20;

20′

, 20″

) introduced into the conductive track (26).