FUSE FOR INTERRUPTING A VOLTAGE AND/OR CURRENT-CARRYING CONDUCTOR IN CASE OF A THERMAL FAULT AND METHOD FOR PRODUCING THE FUSE

• US 20100085141A1
• Filed: 02/14/2008
• Published: 04/08/2010
• Est. Priority Date: 03/26/2007
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Mueller, Michael, Mohr, Thomas, Knab, Norbert, Schulze-Icking-Konert, Georg, Haberl, Nikolas, Kotthaus, Stefan, Stampfer, Stefan
• Granted Patent: US 9,093,238 B2
• Time in Patent Office: Days
• US Class Current: 337/227
• CPC Class Codes: H01H 1/52 Contacts adapted to act as latches
• CPC Class Codes: H01H 2037/768 characterised by the composition of the fusible material
• CPC Class Codes: H01H 37/761 with a fusible element forming part of the switched circuit H01H37/767 takes precedence
• CPC Class Codes: H01H 69/02 Manufacture of fuses
• CPC Class Codes: H01H 85/0418 with ferrule type end contacts
• CPC Class Codes: H01H 85/0458 with ferrule type end contacts
• CPC Class Codes: H01H 85/055 Fusible members
• CPC Class Codes: H01H 85/06 characterised by the fusible material H01H85/11 takes precedence
• CPC Class Codes: H01H 85/143 Electrical contacts; Fastening fusible members to such contacts
• CPC Class Codes: H01H 85/157 Ferrule-end contacts
• CPC Class Codes: H01H 85/165 Casings
• CPC Class Codes: Y10T 29/49107 Fuse making

Abstract

A fuse (10) is proposed for interrupting a voltage and/or current-carrying conductor (12) in case of a thermal fault, having a conductor bar (14) ensuring an electrically conductive connection of the voltage and/or current-carrying conductor during correct operation, said fuse (10) being characterized in that the conductor bar (14) melts upon an increase in temperature above the melting point, and the electrically conductive connection of the voltage and/or current-carrying conductor is interrupted due to inherent surface tension. Also proposed is a method for producing the fuse (10) according to the invention.

Claims

1-35. -35. (canceled)

36. A fuse for interrupting an electrical conductor in event of a thermal fault, comprising:

a conductor bar ensuring an electrically conductive connection of the electrical conductor during correct operation, wherein the conductor bar melts upon an increase in temperature above a melting point and the electrically conductive connection of the electrical conductor is interrupted due to inherent surface tension.

37. The fuse of claim 36, wherein at least one end of the conductor bar is held by a retaining element.

38. The fuse of claim 37, wherein the retaining element comprises a first part for holding the conductor bar and a second part for connecting the retaining element to the electrical conductor, wherein the electrical conductor is coupled to a stamped grid, a printed circuit board or the like.

39. The fuse of claim 38, wherein the first part is configured as a hollow body having one open side.

40. The fuse of claim 39, wherein the hollow body further comprises at least one of an additional chamfer and a slot.

41. The fuse of claim 39, wherein the conductor bar is held by a solder joint in an interior of the hollow body, wherein a melting point of the solder lying beneath that of the conductor bar and above a maximally admissible temperature for correct operation.

42. The fuse of claim 39, wherein the hollow body further comprises at least one raised portion on an outer circumference that constitutes a point of force application for a mechanical deformation of the hollow body for holding the conductor bar.

43. The fuse of claim 38, wherein the first part is configured as an obtuse contact surface.

44. The fuse of claim 38, wherein the first part and the second part of the retaining element are configured as one piece.

45. The fuse of claim 39, wherein the first part and the second part of the retaining element are one of welded and riveted together.

46. The fuse of claim 38, wherein the second part of the retaining element is configured as one of a bar-like, a wire-like, and a strip-like form.

47. The fuse of claim 38, wherein the second part of the retaining element is angled with respect to a preferred orientation of the conductor bar.

48. The fuse of claim 37, wherein the retaining element is an integral component part of a stamped grid.

49. The fuse of claim 36, wherein the conductor bar comprises of one of a metal, a highly electrically conductive alloy, and a soft solder alloy.

50. The fuse of claim 36, wherein the conductor bar comprises a flux core.

51. The fuse of claim 36, wherein the conductor bar comprises a core that contains an activator medium.

52. The fuse of claim 51, wherein the activator medium is a carboxylic acid.

53. The fuse of claim 51, wherein the core contains a mixture of a carboxylic acid and a resin.

54. The fuse of claim 36, wherein the conductor bar comprises a core that contains a salt of a carboxylic acid.

55. The fuse of claim 37, wherein conductor bar comprises a flux encasement that contains one of a carboxylic acid and a salt of a carboxylic acid.

56. The fuse of claim 55, wherein the flux encasement comprises a lacquer coating.

57. A method for producing a fuse comprising a retaining element and a conductor bar for interrupting an electrical conductor in event of a thermal fault, the method comprising:

forming the retaining element to include a first and a second part, wherein the second part formed to connect the retaining element to the electrical conductor, and the first part formed wherein the conductor bar being one of affixed on and inserted into the first part in one of a force-fitting and a positive-locking manner.

58. The method of claim 57, further comprising:

applying a solder to the first part such that at least one of a base and an interior wall of the first part is covered by the solder;

heating at least one of the retaining element and the conductor bar to a temperature between a melting point of the solder and a melting point of the conductor bar;

affixing the conductor bar to the first part such that the conductor bar contacts the solder; and

cooling the fuse to solidify the solder.

59. The method of claim 57, further comprising forming the first part as a hollow body having one open side or as an obtuse contact surface.

60. The method of claim 59, further comprising mechanically deforming the hollow body one of prior to and after heating.

61. The method of claim 58, further comprising heating by a thermal pulse impressed on one of the second part, a raised portion of the hollow body, and the conductor bar.

62. The method of claim 58, further comprising heating by a thermal pulse that is impressed by one of a laser and an infrared light in a non-contact manner.

63. The method of claim 59, further comprising inserting the conductor bar into the hollow body and then heating.

64. The method of claim 57, further comprising applying one of a flux and an activator onto the conductor bar.

65. The method of claim 64, further comprising applying one of the flux and the activator to form a lacquer layer on the conductor bar.

66. The method of claim 57, further comprising checking a connection of the first part and the conductor bar.

67. The method of claim 66, further comprising optically checking the connection.

68. The method of claim 66, further comprising automatically checking the connection.

69. The method of claim 66, further comprising checking the connection with a probe disposed as to be freely displaceable in order to cover a region to be checked in the first part of the retaining element.

70. The method of claim 66, further comprising supplying an operating result for confirming a flawless soldering if a soldering meniscus is detected upon the conductor bar being one of affixed on and inserted into the first part in one of the force-fitting and the positive-locking manner.