Claims
- 1. A pyrotechnic fuse element,
a) comprising a closed housing (1) consisting of an electrically conductive material, in which an explosive is provided, b) said housing containing two terminal zones for electric contacting, which are electrically connected by means of the electrically conductive material of said housing; c) said electric connection of the terminal zones being separable by activating said explosive, and d) said explosive material being embodied as a deflagrating pyrotechnic substance which is provided in such an amount and is configured such that the electric connection of the terminal zones of the hosing is separated in a predetermined time after the deflagrating pyrotechnic substance has been activated, characterized in that e) said housing comprises a weakening portion extending over the entire periphery of its outer wall and formed in the thickness of the housing wall, having a predetermined axial extension and f) that said weakening portion is configured such that, when said deflagrating pyrotechnic substance is activated, said housing cracks over the entire periphery thereof along a defined circumferential line in the area of the circumferential weakening portion, g) or that, when said deflagrating pyrotechnic substance is activated, said housing breaks out entirely at least in a partial area of the circumferential weakening portion between two defined peripheral lines.
- 2. A fuse element according to claim 1, characterized in that said axial extension of the portion of the housing having a smaller wall thickness is larger than zero, preferably larger than 1 mm and smaller than 5 mm.
- 3. A fuse element according to claim 2, characterized in that said wall thickness in the area of the weakening portion is smaller than half the wall thickness of the portions adjacent the weakening portion and is preferably constant.
- 4. A fuse element according to one of claims 1 to 3, characterized in that said circumferential weakening portion of the outer wall is configured such that, at a predetermined nominal current, a predetermined activating temperature for the deflagrating pyrotechnic substance can be produced in predetermined areas by the flow of current through the housing.
- 5. A fuse element according to one of the preceding claims, characterized in that said deflagrating pyrotechnic substance and said housing are configured such that, at a predetermined nominal current intensity, a secure activation of the pyrotechnic substance by the heating of the housing, preferably in predetermined areas, is guaranteed.
- 6. A fuse element according to one of the preceding claims, characterized in that a protective housing is provided which is configured such that splinters produced when the wall of the housing breaks out can be trapped and/or gas or a gas/particle mixture produced when the deflagrating pyrotechnic substance is activated is taken up.
- 7. A fuse element according to one of the preceding claims, characterized in that said housing comprises a substantially hollow cylindrical or cup-shaped part whose two openings at the front sides or whose one opening at the front side are closed by means of a substantially plug-like or cap-like closure element.
- 8. A fuse element according to one of the preceding claims, characterized in that said housing is surrounded by a protective housing and that at least one part of the housing is axially movably held in the protective housing on one side of the cir-circumferential weakening portion, said at least one part of the housing preferably comprising stop means at the outer periphery thereof which limit the axial movement of the housing after the circumferential weakening portion has broken out, and holding means being preferably provided which fix the at least one part after the at least one part has moved axially.
- 9. A fuse element according to one of the preceding claims, characterized in that said deflagrating pyrotechnic substance provided in said housing is penetrated by an electric conductor which is connected at both its ends, respectively, with one of the terminal zones, the conductor being configured such that its heating at a predetermined nominal current will activate the pyrotechnic substance.
- 10. A fuse element according to one of the preceding claims, characterized in that at least in partial areas of the inner wall of the housing which contact said deflagrating pyrotechnic substance, preferably in the area of the circumferential weakening portion, structures are provided which increase the surface effectively contacting said pyrotechnic substance and/or are configured such that in predetermined areas, preferably at corners or edges, locally higher temperatures and/or notch stresses are produced which facilitate the destruction of the circumferential weakening portion and cause smaller fragments.
- 11. A fuse element according to one of the preceding claims, characterized in that a controllable activating device for the deflagrating pyrotechnic substance is provided.
- 12. A fuse element according to one of the preceding claims, characterized in that said deflagrating pyrotechnic substance comprises a first component which has a higher activating temperature and a second component which has a lower activating temperature.
- 13. A fuse element according to claim 12, characterized in that at least said first component has an ageing stability which is sufficient for the desired period of time in which it is to be operable, and it is provided in such an amount and configured such that, when said first component is activated, this first component alone is sufficient to interrupt the electric connection between the terminal zones.
- 14. A fuse element according to claim 12 or 13, characterized in that the activating temperature of the first component is higher and the activating temperature of the second component is lower than the temperature which can be produced at least by partial areas of the housing at a nominal current intensity or by the acitvating device.
Priority Claims (1)
Number |
Date |
Country |
Kind |
100 52 545.8 |
Oct 2000 |
DE |
|
Parent Case Info
[0001] This is a continuation-in-part of International Application PCT/DE01/04016, with an international filing date of Oct. 23, 2001, published in German under PCT Article 21(2).
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
PCT/DE01/04016 |
Oct 2001 |
US |
Child |
10421121 |
Apr 2003 |
US |