DE1438205A1 - Fusible link for low-voltage high-performance fuse - Google Patents

Description

H. SCHURIER AG., LUZIEH

Aktiengesellschaft BROWlJ, BOVERI & CIE., BkDES (Switzerland)

Fusible conductor for low-voltage high-performance fuse "

The subject matter of the invention relates to a fusible conductor for low-voltage high-performance fuses, such as those required in particular for protecting silicon rectifier diodes. Such a fusible link or fuse link is required that it interrupts very briefly in the event of an overload and that it causes the smallest possible overvoltage during the interruption. that the fusible conductor is in the form of a cylinder, in which through a plurality of non-slotted cylinder pieces separate ^Ä eihen of slits in the circumferential direction a plurality

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formed by parallel and in series sine parts are and thereby the ratio between, the cross-section of the unslotted Cylinder pieces and the 'Totalq.uer3Qhn.itt of the parallel melting points, which are on a circumferential line of the Cylinder, is at least 10: 1

This shape results in overloading of the fuse a multitude of rope arcs connected in parallel and in series, which are decisive for the short-term switch-off and the limitation of the overvoltage

An exemplary embodiment of the invention is shown in the accompanying figures. ""

Fig. 1 shows the development of the cylindrical fusible conductor 3, which is divided by four rows of slot-shaped recesses 4, with unslotted cylinder pieces between the rows 3 remain. The efodes of the slits are at least almost semicircular in shape and delimit the Schmelastellen 2. The total shown in Fig. 2 al cross-section of the five parallel melting points 2 must be small, preferably be at least ten times smaller than that shown in FIG. 3 Cross-section of the unslotted cylinder pieces 3 "

It is expediently provided that the melt parts 2 in Cylinder axes are offset from each other ο

According to the invention, the height measured in the axial direction should be Cylinders.tüokes 3 must be at least three and a half times larger than the minimum width of an interruption point 2. This design of the melting points can reduce the resistance of the melting «-" ""

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conductor stay small, which initially results in a small watt loss for the security results «At least as important is the!

the melting point on the unprotected cylinder piece is improved which results in a lower operating temperature and a correspondingly longer service life, all other things being equal result. An increase in the number also has the same effect parallel melt parts, whereby in the borderline case the Slot can become a circular hole

This formation of the melting points with the adjoining massive cylinder pieces results in the advantage relatively short and in their length quite stable arcs. In order to becomes an undesirable rapid increase in arc voltage prevents, in systems with silicon diodes, the diodes lying parallel to the faulty diode from being voltage-reduced Overload protects.

Like Pig. 4 shows, the cylindrical fusible conductor 6 preferably extends in the axial direction at least over the Most of its length extends over the slot 5. This Schlitz results in an informal manner by following the fabrication. punching out the slots in a flat sheet of silver, it is not completely rolled up into a full cylinder. This slot has the advantage that when pulling the Securing with extinguishing sand, this sand from the inside of the cylinder can easily reach the outside and thus all melting points are evenly embedded in the extinguishing sand. The fusible link with the quenching sand is in a cylindrical one Synthetic resin body, which has fiberglass reinforcement and through

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METAL CONNECTING TUBES AT THE FRONT SIDES © s © hl © 88 @ a is · The fusible link itself is connected to the connecting pieces a connected by point welding *

The Zylin & erform the ächmelzleiterg are Übs a very good © mechanical stability and thus enables a large he θ Number melting st rush to scold in series, fuse-circulation higher voltages Matters "Gleiohzeitig but can Zylindervrand be thinner," which thin melting points and a great agility of the Schmelslei $ @ rs would be achieved without significant manufacturing difficulties _e ]) The agility is of essential importance for you application of the solution according to the invention given the known sensitivity of silicon diodes.

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Claims (5)

32/61 -5-. U38205 Claims / Fusible conductor for Iiederapannungs-BochleiatungB-Sioiieru »g _f characterized» in that it has the shape of a cylinder (6), in which by several unprotected cylinder pieces (3) separated by slits in circumferential direction a plurality of τοη parallel and in line lying · »Sehaelzstellen are formed, and the ratio between the cross-section of the unslotted cylinder pieces (3) and the total cross-section of the parallel melt pieces (2), which lie on a circumferential line of the cylinder» is at least 10 t 1. 2) fusible link according to claim 1 »characterized in that the height of a cylinder stucco, measured in the axial direction (3) at least three and a half times larger than the smallest width an interruption point (2) is " 3) fusible link according to claim 1 »characterized in that the cylinder (6) has an SiOH in the axial direction at least the like extending over the part of its length grösaten Schiita (5). 4) fusible conductor according to claim I _9, characterized in "that the ends of the slots delimiting the melting points are approximately semicircular" 09808/0230 U3 & 205 5) fusible conductor according to claim 1, characterized in ₉ that the ächmelzstellen (2) to each other in the cylinder axis direction are offset " ■■■■■■. ', ■: Λ ö ö f.