Abstract
Disclosed is an ignition arrangement for multiple pyrotechnic articles, which includes a moulded body including a housing for an igniter cord, and also including sides and partitions. The housing is formed by pairs of parallel ribs separated from one another, the ribs of each pair being joined under the igniter cord, thus forming the bottom of the moulded body. Aligned openings are provided in the igniter cord, having inclined opposing surfaces that converge transversely towards the inside of the igniter cord, such as to channel the ignition sparks scattered in the arrangement towards an area of an ignition fuse held against a corresponding opening, such that the fuse is ignited from the igniter cord and ignition spreads to a pyrotechnic element located outside the moulded body.
Claims
1. An ignition arrangement for multiple pyrotechnic articles comprising a molded body including therein an igniter cord provided in a housing which extends lengthwise in the molded body, and at least one opening in the igniter cord, said igniter cord having access to the exterior of the housing; wherein said at least one opening is included in a series of elongated openings spaced along the igniter cord in lengths proportional to acceleration or delay for ignition propagation, and said at least one opening has at least two opposing inclined surfaces which converge inside of said igniter cord to direct propagation of ignition sparks from the opening to the exterior of the housing and provide ignition to an ignition fuse of at least one pyrotechnic article located outside of the molded body; wherein each opening of said series of elongated openings present in the igniter cord is contained in said molded body, bounded by partitions extending transversely in the housing and flanks extending parallel to the housing, to define a cavity which prevents projection of ignition sparks emitted from inside the opening in the igniter cord to the exterior of the molded body; and a holder formed by a thermoplastic plate that is folded to fit into the cavity, and which forces a region of the ignition fuse against said at least one opening.
2. The ignition arrangement of claim 1, wherein said holder is formed independently of the molded body and comprises an adaption surface which includes pairs of support flaps which limit penetration of the holder into the cavity of the molded body, and includes a pair of tabs to maintain the holder in the cavity, while a reverse side of the adaption surface includes cooperating stop protrusions that maintain separation between folded sides of the holder when fit into the cavity; and wherein said holder includes a push tab and a notch configured to contain and push on the ignition fuse against said at least one opening.
3. The ignition arrangement of claim 1, further comprising a tubular body extending coaxially from one end of said housing and toward the exterior of the molded body; wherein said tubular body includes a first cavity extending longitudinally and axially from an open end in said tubular body inside said housing to narrow in section to structure a second cavity for reception and holding of an external ignition head to the ignition arrangement.
4. The ignition arrangement of claim 1, further comprising connecting members, at each end of the molded body, configured to connect said molded body to one or more additional molded bodies containing igniter cords.
Description
DESCRIPTION OF THE DRAWINGS
(1) An embodiment example, without limitation, of an ignition arrangement for multiple pyrotechnic articles is shown in the accompanying drawings, in which:
(2) FIG. 1 shows the main base of a molded body seen from below to better show the ignition openings of equal length in the igniter cord, according to the invention.
(3) FIG. 2 shows on a similar scale and like FIG. 1, the main base of a molded body seen from below showing the igniter cord with ignition openings of different lengths, according to the invention.
(4) FIG. 3 shows, according to the invention and taken from the perspective above and on a similar scale as that used in FIGS. 1 and 2, a particular embodiment of the ignition fuse holder in position prior to being bent in half for use.
(5) FIG. 4 shows, taken from the perspective above and on a similar scale as that used in the previous figures, the ignition arrangement for multiple pyrotechnic articles according to the invention, in the position prior to being rotated 180 degrees for its usual application and illustrating the figure of the holder's use prior to contact with a particular area of the ignition fuse, in the forward position above a cavity of the molded body and prior to its placement against an opening of the igniter cord at the bottom of the cavity, once the holder has been inserted into the cavity and is secured in the molded body.
(6) FIG. 5 shows, taken from the perspective below and at a similar scale as that used in FIG. 4, the ignition arrangement for multiple pyrotechnic articles according to the invention, in position prior to being rotated 180 degrees for their usual application and illustrating in a simplified way a position prior to use, in which for greater clarity the ends of the ignition fuses sheathed in commercial thermoplastic heads and the portions of the ignition fuses to be connected to the pyrotechnic elements are shown.
(7) FIG. 6 shows, on a similar scale as that shown in FIG. 5, a simplified cross-section of the ignition arrangement for multiple pyrotechnic articles according to the invention, in a position prior to being rotated 180 degrees for its usual application and illustrating the arrangement of an area of the fuse pressed by the holder against the igniter cord.
PREFERRED EMBODIMENT OF THE INVENTION
(8) In a simplified embodiment according to the invention proposal, as suggested by FIGS. 1 to 6, an ignition arrangement for multiple pyrotechnic articles is comprised of a molded body (1), in the example of an oblong figure, where during the molding process an igniter cord (3) has been included in a housing (2) that extends along the molded body (1). In the example, the housing (2) is seen to be formed by pairs of ribs (2) arranged in parallel and separated from each other and the ribs of each pair are internally joined under the igniter cord. As FIG. 6 shows best, in the molded body, at least one opening (4) is elongated with at least two inclined and opposite surfaces (5) that obliquely tend to converge toward the inside of the igniter cord (3) to channel the spread of ignition sparks toward an area (23) of an ignition fuse (22), which, in the example, is provided with a thermoplastic head (32), and that area (23) to be placed against the opening (4) in order to be ignited by the igniter cord (3) to propagate ignition to a pyrotechnic element (not represented) located outside the molded body (1).
(9) Referring to the figures, especially FIG. 2, a series of openings (4) of equal length and openings (4) of different lengths are presented in the example following the same lengthwise alignment with the igniter cord (3), and this, although any other possible orientation could be used. All openings (4) and (4) including at least two inclined surfaces (5), facing each other and tending to converge toward the inside of the igniter cord (3) channeling the exit of the ignition flare and/or sparks from the igniter cord (3) to the outside to ignite each of the ignition fuses (22) held against the corresponding openings (4) and (4). The separation between openings (4) and (4) corresponds to sections (6) without openings and whose lengthwise extensions determine the delay required for the ignition fuses (22). However, since the openings (4), (4) are allowed to be of different lengths in the example, these sections (6) are unequal to each other and proportional to the acceleration or delay required to ignite the ignition fuses (22).
(10) As shown in FIG. 1, each of the openings (4), and each opening (4) and (4) in FIG. 2, between sections (6) of the igniter cord (3) is contained between partitions (7) that exceed the height of the ribs (2) and are presented in the example as parallel to each other, distributed along the molded body (1) and with a separation proportional to that required by the lengthwise extension and established separation between openings (4) and (4) in order to limit the propagation of the ignition flare and/or sparks between adjacent openings.
(11) On each side of the igniter cord (3) and externally supporting the pairs of ribs (2) which, together with the bottom (9) define the housing (2), are seen side walls or flanks (8) of similar height to the partitions (7), where they match up with cavities (10) that keep the openings isolated from each other, also shown in FIGS. 4 and 6, with a separation proportional to that required by the length and established separation between openings, which prevent or limit the spread of the ignition flare or sparks from one opening to the adjacent opening. The flanks (8), in the area of their upper edges, provide slots impressed into portions of the wall (11) which, as best seen in FIGS. 4 and 5, extend into each flank (8) downward until aligning with corresponding retention sockets (12).
(12) Just as seen in FIGS. 3 and 4, better in FIG. 3, the preferred holder (13) consists of a thermoplastic plate that has an adaptation surface (14) and an opposite surface (15). The plate that matches with the holder (13) that is easily bent in half for use as shown in FIG. 4, and from its smaller sides (16) protrude pairs of support flaps (17) on the upper edges of the flanks (8), limiting the penetration of the holder (13) into the cavity (10, 10) provided for its use. Protruding from the adaptation surface (14) of the holder (13) and under the pairs of support flaps (17) are seen pairs of tabs (18) for sliding into the guide path provided by the slots impressed into portions of the wall (11) and after the snap-in connection, to work with the retention sockets (12) sized to tightly receive the pairs of tabs (18) and thus act as an end stop for the holder (13) blocking its upward or downward slide in the corresponding cavity (10, 10) provided for its use, as shown best in FIG. 5.
(13) On the surface (15), opposite the adaptation surface (14) on the thermoplastic plate constituting the holder (13) and near its smaller sides (16) protrusions (19) are seen that work together as stops to keep both sides apart when the plate that constitutes the holder (13), is bent in half according to FIG. 4, and the holder is ready to be inserted into the corresponding cavity (10, 10) in the molded body (1) as provided in FIG. 5. Returning to FIG. 3, a push bar (20) of suitable amplitude and height protrudes vertically on the surface (15) and is extended, centered with respect to the smaller sides (16), providing a lower and central notch (21) for containment and pushing, as shown in FIG. 4, on an area (23) of the ignition fuse (22) to place it against at least one such opening (4, 4).
(14) In the example, the tubular body (24) lengthens one end of the molded body (1), and is intended to allow for tight insertion of the protruding portion of the final portion of the igniter cord (3) of a molded body (1) similar to the goal of obtaining an ignition arrangement for multiple pyrotechnic articles of greater length. Alternatively, the tubular body (24) allows for the adaptation of an ignition head or ignition initiating element, for example, an electrical initiator (not represented) capable of causing the ignition of the igniter cord (3) in the pyrotechnic arrangement. Additional connecting members (30) and (31) are provided at either end of the molded body (1) to ensure connection between adjacent molded bodies.
(15) Consistent with the figures and as seen best in FIGS. 1 and 2, the tubular body (24) is provided with a tubular cavity (25), with a cross section appreciably equal to or even greater than the cross section of the protruding final portion of the igniter cord (3) of the molded body (1) to be lengthened. The tubular cavity (25) extends lengthwise and axially from the entrance opening (26) to several radial rails (27) which, decreasing the [cross] section of the tubular cavity (25), extend to the base (28) provided with a hole (29) to allow ignition propagation to the igniter cord (3) of the molded body (1) to be lengthened.
