Fuse assembly and method for assembling the same
A fuse assembly that includes a low energy exploding foil initiator (LEEFI) located in a housing thereof. The LEEFI is supported in the housing by a sleeve made of a compliant material that protects the LEEFI by dampening shocks and vibrations applied to the housing. At least a portion of the LEEFI is press-fit into the sleeve such that an interference fit exists between an outer cylindrical wall of the LEEFI casing and in inner wall of the housing. The sleeve includes a latch assembly at one end having a plurality of tabs that are circumferentially spaced-apart from one another. Each of the plurality of tabs includes a cantilever beam having a head, the head including a bottom surface pressed against a top surface of the external annular flange of the LEEFI casing.
1 . A fuse assembly comprising:
a low energy exploding foil initiator that includes a casing with an external annular flange;
a housing including:
a through opening defined by an inner wall, the inner wall having an annular groove;
a first shelf; and
a sleeve disposed between the low energy exploding foil initiator casing and the inner wall of the housing; the sleeve including:
an outer surface that is pressed against the inner wall of the housing;
an outer annular protrusion that resides in the annular groove of the housing;
a bottom surface that rests against the first shelf of the housing;
a shelf on which at least a portion of the external annular flange of the casing rests;
an upper latch assembly comprising a plurality of tabs that are circumferentially spaced-apart from one another, each of the plurality of tabs including a cantilever beam having a head, the head including a bottom surface pressed against a top surface of the external annular flange of the low energy exploding foil initiator casing.
2 . The fuse assembly according to claim 1 , wherein the housing includes a second shelf located above the first shelf, the annular groove being disposed between the first and second shelves, the sleeve having a lip with a bottom surface that is pressed against a top surface of the second shelf.
3 . The fuse assembly according to claim 1 , wherein the head of each of the plurality of tabs includes a chamfered top surface that facilitates an insertion of the low energy exploding foil initiator casing into the sleeve.
4 . The fuse assembly according to claim 1 , further comprising a band that circumscribes the plurality of tabs, at least a portion of the band residing in a groove of each of the cantilever beams and configured to restrict radial outward movement of the cantilever beams.
5 . The fuse assembly according to claim 4 , wherein the band is a rigid O-ring.
6 . The fuse assembly according to claim 4 , wherein the band is made of a rigid silicone.
7 . The fuse assembly according to claim 1 , wherein there exists an interference fit between the low energy exploding foil initiator casing and the inner wall of the sleeve.
8 . The fuse assembly according to claim 1 , wherein the sleeve is a monolithic structure made of a single piece of material.
9 . The fuse assembly according to claim 1 , wherein the sleeve is made of a shock absorbing material.
10 . The fuse assembly according to claim 9 , wherein the sleeve is a urethane injection molded structure having a shore hardness of 95 A.
11 . The fuse assembly according to claim 1 , wherein the housing is made of a material selected from the group consisting of steel and aluminum.
12 . The fuse assembly according to claim 1 , further comprising one or more electrical leads protruding from an end of the low energy exploding foil initiator casing, the one or more electrical leads being electrically coupled to a respective one or more traces of a flexible electrical connector.
13 . The fuse assembly according to claim 12 , wherein the one or more electrical leads are electrically coupled to a printed circuit board by the flexible electrical connector.
14 . The fuse assembly according to claim 13 , wherein the printed circuit board is located inside the housing.
15 . A method of mounting a low energy exploding foil initiator inside a housing, the method comprising:
a first insertion process that includes inserting a sleeve into a through opening of the housing, the through opening being defined by an inner wall having an annular groove, the housing further including a first shelf inside the through opening that protrudes radially inward from the inner wall, the sleeve having an outer surface that is caused to press against the inner wall of the housing, and a bottom surface that is caused to rest against the first shelf when the first insertion process is complete, the sleeve further including an outer annular protrusion that is caused to at least partially reside in the annular groove of the housing during the first insertion process; and
a second insertion process that includes inserting a casing of the low energy exploding foil initiator into a through opening of the sleeve so that the sleeve is disposed between the low energy exploding foil initiator casing and the inner wall of the housing, the sleeve including a shelf on which at least a portion of an external annular flange of the casing rests when the second insertion process is complete, the sleeve further including an upper latch assembly comprising a plurality of tabs that are circumferentially spaced-apart from one another, each of the plurality of tabs including a cantilever beam having a head, the head including a bottom surface that is caused to press against a top surface of the external annular flange of the low energy exploding foil initiator casing when the second insertion process is complete.
16 . The method according to claim 15 , wherein the housing includes a second shelf located above the first shelf, the annular groove being disposed between the first and second shelves, the sleeve having a lip with a bottom surface that is caused to press against a top surface of the second shelf when the first insertion process is complete.
17 . The method according to claim 15 , wherein the head of each of the plurality of tabs includes a chamfered top surface, during the second insertion process an outer surface of the low energy exploding foil initiator casing acts on each of the chamfered top surfaces to cause each of the heads to move radially outward to facilitate the insertion of the low energy exploding foil initiator casing into the sleeve.
18 . The method according to claim 15 , further comprising applying a band around the cantilever beams to restrict radial outward movement of the cantilever beams.