EP0266783B1 - Ignition element - Google Patents

Description

The invention relates to an ignition component according to the preamble of claim 1.

Such a firing component with an integrated discharge capacitor to prevent false tripping due to interfering interference voltages is known from US Pat. No. 2,818,020 in the form of a cup housing, the opening of which is hermetically sealed by holding the connecting wires by means of the base body. There is a stopper above the base body, into which a comb-shaped sandwich capacitor is enclosed and electrically connected to connecting lines which emerge from the stopper and pass into a filling of primary explosive, in which the ignition bridge is stretched between them.

Such a construction of the classic ignition component is evidently expensive in terms of production technology because of the combination of very different assemblies and is functionally critical with regard to the transition of the ignition bridge holder from the pouring plug for the capacitor into the primary explosive. An electrical ignition element does not have these disadvantages of the complex manufacturing problems, as is known from DE-A 3 502 526. Because there a structure is formed directly on a carrier body surface from two mutually offset electrode regions, which are interconnected by an electrically conductive connection serving as an ignition bridge. However, in order to achieve sufficient capacity for a sufficiently effective interference suppression capacitor between these electrodes, which are arranged in one plane and bridged by the ignition path, a very small electrode spacing must be provided, which requires a correspondingly complicated shape for the meandering course of the ignition bridge. In spite of only a small capacitance of the protective capacitor, this results in high manufacturing and functional problems due to the risk of unwanted gap bridges, which render the function of the capacitor or even the ignition bridge obsolete.

In recognition of these circumstances, the invention is based on the object of designing an ignition component of the generic type in such a way that it is cheaper to manufacture on the one hand and high protection of a discharge capacitor as close as possible to the ignition bridge on the other hand.

This object is achieved in that the generic ignition component is designed according to the characterizing part of claim 1.

According to this solution, the carrier of the ignition bridge itself is the protective capacitor connected in parallel, in that either the base body itself serves as the dielectric of a layer capacitor or else as the carrier of a commercially available chip capacitor, between whose electrode connections the ignition bridge is applied.

The base body or the insulating body thus not only form the carrier for the ignition bridge, but also for the capacitor if they do not represent the capacitor itself. The size of the base body or insulating body is thus available for dimensioning the capacitance of the protective capacitor. The ends of the ignition bridge are extremely close to the capacitor electrodes, so that there are practically no connecting lines that receive interference radiation and can lead to the unwanted triggering of the ignition bridge. On the other hand, a long ignition bridge can be formed, so that production-related short circuits are reliably avoided.

• Fig. 1 ein Anzündbauteil in der üblichen Bauweise einer Anzündpille,
• Fig. 2 im Schnitt ein erfindungsgemäß ausgestaltetes Anzündbauteil mit Integration des SchutzKondensators in den Grundkörper für die Halterung der Anschlußdrähte,
• Fig. 3 in Aufsicht gemäß Pfeilangabe 111-111 das Ausführungsbeispiel anch Fig. 2,
• Fig. 4 und
• Fig. 5 abgewandelte Ausführungsbeispiele für die Integration eines Schutzkondensators in den Grundkörper nach Fig. 2,
• Figur 6 einen Schnitt eines weiteren Ausführungsbeispiels der Erfindung,
• Figur 7 eine Aufsicht in Richtung der Pfeile VII-VII nach Figur 6,
• Figur 8 eine Alternative zum Ausführungsbeispiel nach Figur 6,
• Figur 9 eine Aufsicht in Richtung der Pfeile IX-IX nach Figur 8,
• Figur 10, 11, 12 Alternativen zu dem Ausführungsbeispiel nach Figur 6 und Figur 8,
• Figur 13 eine Weiterbildung der Ausführungsbeispiele und
• Figur 14 deren Ersatzschaltbild.

Advantageous refinements of the solution according to the invention result from the following description of preferred exemplary embodiments. It shows.

• 1 is an ignition component in the usual design of an ignition pill,
• 2 shows in section an ignition component designed according to the invention with integration of the protective capacitor in the base body for holding the connecting wires,
• 3 in supervision according to arrow 111-111 the embodiment of FIG. 2,
• Fig. 4 and
• 5 modified exemplary embodiments for the integration of a protective capacitor in the base body according to FIG. 2,
• FIG. 6 shows a section of a further exemplary embodiment of the invention,
• FIG. 7 shows a top view in the direction of arrows VII-VII according to FIG. 6,
• FIG. 8 shows an alternative to the exemplary embodiment according to FIG. 6,
• FIG. 9 shows a top view in the direction of the arrows IX-IX according to FIG. 8,
• 10, 11, 12 alternatives to the exemplary embodiment according to FIG. 6 and FIG. 8,
• Figure 13 is a development of the embodiments and
• Figure 14 their equivalent circuit diagram.

An ignition pill has a base body (1) on which an insulating body (2) is arranged. Lead wires (3, 4) are guided through the base body (1) and are connected at solder points (5, 6) to an ignition wire (7) which is carried by the insulating body (2).

The ignition wire (7) and the insulating body (2) are embedded in ignition kits (8, 9) which surround a protective lacquer layer (10). In the exemplary embodiments described below, the primers are not shown in detail.

In the exemplary embodiment according to FIGS. 2 to 5, the disk-shaped base body (1) is not made from glass, but from a ceramic with suitable dielectric properties. An electrically conductive capacitor coating (11) is applied to the underside of the base body (1). A capacitor coating (12) is provided on the opposite top. The insulating body (2) is applied to this. The insulating body (2) carries the ignition bridge (7), which is an ignition wire or made of Wi the resistance paste is applied to the insulating body (2).

The connecting wires (3, 4) protrude just above the ignition bridge (7) (see FIG. 2). The connecting wire (3) is electrically conductively connected to the capacitor coating (11) on the underside and one end of the ignition bridge (7). It is electrically insulated from the capacitor covering (12). Correspondingly, the connecting wire (4) is electrically conductively connected to the ignition bridge (7) and the capacitor coating (12) on the upper side; however insulated from the capacitor coating (11). The base body (1) thus not only forms the stable leadthrough for the connecting wires (3, 4) and the holder for the insulating body (2) with the ignition bridge (7), but at the same time an electrical capacitor due to its capacitor coatings (11, 12), which is electrically connected in parallel with the ignition bridge (7).

Since the ignition bridge (7) is connected directly to the connecting wires (3, 4) to which the capacitor linings (11, 12) are also connected directly, only a few connection points are necessary on the one hand. On the other hand, the capacitor is spatially extremely close to the ignition bridge (7), so that interference radiation between the capacitor linings (11, 12) and the ignition bridge (7) cannot take place.

In the embodiments according to FIGS. 4 and 5, a plurality of capacitor coatings (11, 12) are provided to increase the capacitance in the base body (1), as a result of which a stacked capacitor is created. A desired capacity can be achieved by cascading a corresponding number of individual elements.

In order to obtain an L-C-L protection circuit, tubes made of a ferrite material can be attached to the connecting wires (3, 4) (see FIGS. 13 and 14).

In the exemplary embodiments according to FIGS. 6 to 13, a commercially available single-chip capacitor component (13) is provided instead of the insulating body (2) and the capacitor coatings (11, 12) of the base body (1). The ignition wire (7) runs between its capacitor coatings (11, 12). A resistance paste can also be applied to the component (13) as the ignition bridge.

In the exemplary embodiment according to FIGS. 6 and 7, the component (13) is arranged lying on the base body (1). One solder or weld connection is sufficient here to connect the connecting wire (3) to the capacitor coating (11) and one end of the ignition bridge (7) and to connect the connecting wire (4) to the capacitor coating (12) and the other end of the Ignition bridge (7).

In the exemplary embodiment according to FIGS. 8 and 9, the component (13) is arranged standing on the base body (1). The component (13) can be glued to the base body (1).

In the embodiments according to FIGS. 6, 7, 8, 9 and 11, the ignition bridge (7) extends on one of the large surfaces of the component (13), it being laid in a Z-shape according to FIG. In the embodiment according to FIG. 10, the ignition bridge (7) runs on the end face of the component (13) facing away from the base body (1). In the exemplary embodiment according to FIG. 12, the ignition bridge (7) extends from one side over the end edge to the other side of the component (13).

In this embodiment too, the capacitor is arranged directly at the ignition bridge (7). The capacitor component (13) also takes on the function of the insulating body (2). It is also advantageous here that a commercially available capacitor component (13) can be used to manufacture the ignition component.

After the execution according to FIG. 13, tubes (14, 15) made of a ferrite material are pushed onto the connecting wires (3, 4). This creates an L-C-L protective circuit for the ignition bridge (7). The equivalent circuit diagram of this protective circuit is shown in FIG. 14.

Claims (4)

1. An ignition component part with a base body (1) for the retention of electrical connecting wires (3, 4) for an igniting bridge (7) and a capacitor connected in parallel with this, characterised in that the capacitor is formed or respectively arranged in or directly on the base body (1) itself and the igniting bridge (7) is connected directly on the capacitor.

2. An ignition component part according to Claim 1, characterised in that arranged between the igniting bridge (7) and the base body (1) is an insulating body (2) through which there extend the connecting wires (3, 4) connected to the capacitor (11, 12) on or in the base body (1).

3. An ignition component part according to claim 1, characterised in that connected on the base body (1) between the connecting wires (3, 4) is a chip-capacitor component part (1), between the plates (11, 12) of which the igniting bridge (7) extends.

4. An ignition component part according to one of the preceding claims, characterised in that the connecting wires (3, 4) held by the base body (10) carry ferrite tubes (14, 15).

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