DE3447502A1 - Board as a circuit carrier having a conductor track in the form of a layer - Google Patents

Abstract

A board as a circuit carrier having a conductor track (B) in the form of a layer, that is to say, for example, a thin-film conductor track (B) and/or a thick-film conductor track (B), and/or an etched conductor track (B) on a substrate (S) in the form of a board, and having an electrical fuse (D) which responds to an overload, contains a predetermined interruption point (D) for interrupting the conductor track (B) and is inserted into the conductor track (B) in the longitudinal direction, the predetermined interruption point (D) containing a compact wire (D) having a wire section (A) which is fitted in a floating manner. <IMAGE>

Description

Plate as circuit carrier with layered conductor

train.

The invention relates to a further development of the in the preamble of Claim 1 defined plate.

The invention was particularly aimed at protecting the carrier plates of Developed subscriber lines of a telephone switching system. The invention However, it is also important for the protection of printed circuits, especially against destruction by short circuit with power lines.

The object of the invention is to protect the plate and / or the Protection of components of your circuit by a new type of electrical fuse to achieve that, so to speak, integrated or hybrid, instead of as a separate compact Component, is inserted into the circuit.

A particularly easy to manufacture and little space and weight having a very shock-resistant and vibration-resistant solution to this problem is in the claim 1 specified.

Allow the additional measures specified in the subclaims additional benefits. Thus, the measures according to claim 2 allow the pollution of the board and / or of components of its circuit and / or of other components the environment, which are not attached to the plate (which e.g. on other panels are attached) at least largely to prevent, as well as 3 and 4, in preferred applications, the particular advantages, namely light weight Manufacturability, small footprint and low sensitivity to mechanical To exploit shocks, namely: 3, if in the event of an interruption the power supply the circuit is to be interrupted and 4, if in the event of an interruption the connection be interrupted between the telephone exchange and the subscriber line target.

The invention is illustrated schematically in the two figures from FIG two different sides (cut open) shown embodiment further explained.

The figures therefore show two sections oriented perpendicular to one another by a variant of the invention in which on the substrate S one or a plurality layered conductor tracks is attached. Such conductor tracks B thus form e.g. Thin-film conductor tracks and / or thick-film conductor tracks and / or etched conductor tracks.

In the conductor track B is the responsive to an electrical overload Securing with the compact, e.g.

Bonded wire D to interrupt the conductor path B in the event of an interruption, inserted into the conductor track B in the longitudinal direction. The thin wire D contains as a target interruption point a suspended wire section A that melts or vaporizes, if too much current flows through it. So it interrupts the current if necessary the conductor track B before permanent damage occurs to the conductor track B itself and before the current of the conductor track B damages other circuit components of the The thickness of the wire D can easily be determined by experiments or by taking into account the previous fusible link experience to the adapted to the respective needs be that the wire D with the predeterminable The setpoint of the current flowing through it melts or vaporizes.

Such a structure of a fuse on a circuit board with layered conductor tracks is particularly suitable for series production with high Quantities suitable. This solution can be produced with simple means, needs especially little space in any spatial direction, has little weight, that disturbs could, hardly needs any material and is still a very stable, shock-resistant and vibration-proof solution even with very high mechanical loads. It allows thus already largely the protection of the plate and / or the protection of components their circuit in a particularly favorable manner, even if no cover cap P is attached is.

A fuse D constructed in this way can e.g. be inserted into a conductor track B of the Power supply of the circuit can be inserted and thereby the circuit if necessary and / or protect the power supply generator. Such a fuse D can also be inserted into the circuit itself. The circuit can be a subscriber line circuit of a telephone switching system, each such wire section A e.g. inserted into one of the subscriber line arteries forming sub-conductor tracker B. is.

The wire D or its section A can also be provided with a cover cap P are covered, which in the event of an interruption splashes or vapors of the melted or evaporating section A at least largely intercepts.

The shape and material of the cover cap can be selected as desired and other needs, such as

low weight and / or wide, light and vibration-proof bondable support surface for support or fastening on the substrate S, adaptable. E.g. the shape can be rectangular be, around the cap P with particularly little difficulty by means of a manipulator to attach over section A, e.g. to be able to glue it on. In any case, the Cover cap P serve to prevent contamination of the plate and / or components their circuit and / or other components in the vicinity that are not on the Plate are attached (which are e.g. attached to other plates) - completely or at least largely to prevent. Such pollution would have otherwise often devastating consequences for the circuitry of the plate and / or the circuits the area around the plate, e.g. on neighboring other plates, e.g. if a low-resistance Short circuit with the 220 V high voltage network is the cause of the melting or evaporation of section A.

A single cover cap P can in principle also be used at the same time several sections ASalso, so to speak, several fuses A or D, at the same time as Cover the splash guard.

Under section A, in the substrate S, in principle, a - can also be preferred small - hole L must be attached, cf.

the two figures. The hole L can be used, for example, to open the very hot air inside the cap P to expand before the Cover cap P is blasted off the substrate S. The hole L should be small enough that it does not allow too many splashes and vapors to escape in the event of an interruption.

4 claims 2 figures - blank page -

Claims (3)

Claims. Plate as circuit carrier with - layered conductor track (B), so z.3. Thin film conductor (B) and / or thick film conductor (B) and / or etched Conductor (3)> on a plate-shaped substrate (S), and - one on overload appropriate electrical fuse (D), the elne target interruption point (D) for interrupting the conductor track (3) and in the longitudinal direction in the conductor track (3) is inserted, d u r c h e k e n n n z e i c h n e t, that - the target interruption point (D) contains a compact wire (D) with a suspended wire section (A). 2. Plate according to claim 1, d a d u r c h g e k e n n z e i c h n e t that - the wire section (A) with an intercepting spatter when interrupted Top cap (P) is covered. 3. Plate according to claim 1 or 2, d a d u r c h t e k e n r. it is clear that - the wire section (A) in a conductor track (B) of the power supply is inserted into the circuit. Plate according to claim 1 or 2, d a d u r c h e k e n n z e 1 c h n e t that - the circuit is a subscriber line circuit of a telephone switching system forms, and - the wire section (A) in a subscriber line forming Conductor (B) is inserted.