EP0144854A2 - Method of manufacturing a miniature fuse, and miniature fuse - Google Patents

Abstract

The invention relates to a method for producing a miniature fuse and a miniature fuse itself. Known housings with three chambers and a separate cover are difficult to manufacture and, because of their complicated shape, are susceptible. According to the invention, an internally substantially smooth-faced, externally cylindrical housing is preferably formed from identical tube halves, the end faces of which are closed either by appropriately designed connecting electrodes or by molded end walls, the electrodes always carrying the fuse element on the inside and the connecting wires on the outside. Here, an intermediate carrier is preferably used, which comprises the electrodes and the fuse element attached to them. In any case, the production is simplified. In addition, there is no longer any need to provide heat shrink tubing for insulating contact caps.

Description

The invention relates to a method for producing a miniature fuse in which, after fixing the distance between two connecting electrodes, a fusible conductor is fastened between them in an electrically conductive manner and then an initially two-part housing surrounding the electrodes and the fusible conductor is closed. In addition, the invention relates to a miniature fuse, which consists of a housing composed of two halves with electrodes held therein, on which there are connecting wire ends on one side and a fuse element is fastened on the other side.

The previously known miniature fuses, which are also called pico fuses, can be viewed as a miniature fuse of normal size, for example 20 mm in length; for example, they consist of a ceramic tube, caps are glued to both sides, to which the fusible conductor located inside the ceramic tube and the connecting wires are soldered. The manufacture of such a fuse, which is only approx. 7 mm long and approx. 2.4 mm thick, is still largely carried out manually, so that comparatively high production costs are present. The reason for the predominantly manual production lies in the difficult handling of the Fusible wire, which in extreme cases has a diameter of only 8 µm.

In order to counter these difficulties, attempts have already been made to divide the inside of a prismatic housing into three chambers and to reserve the two outer chambers for connecting the fuse wire to the connecting wires and the inner chamber for the fuse wire. In view of the small size of the components, however, this proposal is difficult to implement, and the previously conventional rotationally symmetrical design is also abandoned.

It is therefore an object of the invention to propose a method for producing the type mentioned at the outset and a miniature fuse itself, it being possible to use very simple housings, the manufacture of which, despite the small size, presents no difficulty, and the outer shape of the miniature fuse is essentially as possible should be cylindrical smooth.

To solve this problem, which relates to the method, it is provided according to a first proposal that the housing is essentially smooth on the inside, that the spaced electrodes are pre-attached in one housing part and that after the fuse element has been attached, the housing is closed with the electrodes permanently attached to the inner surface.

According to a second proposal, it is alternatively provided that the housing is essentially on the inside Lich smooth surface is formed that the fusible conductor is fastened between the spaced electrodes and that the electrodes are placed together with the fusible conductor in one housing part and then the second housing part is laid to fix the electrodes and the fusible conductor and to close the housing.

The above-mentioned object with regard to a miniature fuse is achieved, on the one hand, in that the housing is of tubular design and is essentially smooth on the inside and that the electrodes close the end faces of the housing in the manner of a stopper.

On the other hand, it is proposed as an alternative to a miniature fuse that the housing be tubular and consist of a substantially smooth surface on its inner surface and closed on both ends except for a passage for the respective contact and on the inside with at least one transverse to the longitudinal axis in the front Partition plane, possibly extending to the outside of the housing, and connected to the contact there or provided with one-piece arm.

The micro-fuse manufactured according to the above-mentioned methods and the one protected is each externally presented as a cylindrical body, which does not carry any thickening due to caps or the like at its ends, but rather its end faces either in the manner of a; Plug through the electrodes or through end walls, each with a passage for the electrodes, are closed. In this way, there are excellent conditions for marking printing, without the need for a shrink tube or a powder coating. The defined diameter limit can therefore benefit fully from the size of the housing, which indirectly facilitates production.

If the two housing parts are designed as tube halves, they can be cut to length continuously, that is to say they can be produced in a manner that is hard to beat in terms of simplicity. In a thermal welding process for joining the two tube halves, a welding lip can be formed on one narrow side, the two tube halves then being placed in opposite directions when the housing is closed, so that a welding lip meets a smooth narrow side without a welding lip.

The pre-attachment or the final attachment of the electrodes within the housing halves and the cohesion of the housing itself can be carried out with the aid of an adhesive, or a connection is brought about by heating, in which case the housing material must be a thermoplastic. For heating, ultrasound heads, radiators or other heat sources can be used, which are usually used when gluing and embedding parts in thermoplastics. For better adhesion of the electrodes in the plastic material, the other surface can be roughened, for example sandblasted or etched.

When the housing is closed, the easy penetration of the electrodes into the inner surface of the tube half, if they are used practically as sealing plugs, can be accepted. This penetration even improves the fit of the electrodes in the housing and thus the cohesion of the pico fuse. If the surfaces of the electrodes facing the inner surfaces of the housing are sharp-edged, this process is made even easier. With circumferential V-channels two or more circumferential sharp edges can be created, between which there is sufficient space to accommodate the slightly squeezed plastic material.

The easy penetration of the electrodes into the inner surface of the housing means that the fuse element is not on the outside is soldered to the periphery of the electrodes, but more in the center so that it is not sheared off when the housing is closed. A sufficiently central attachment of the fuse element is obtained if the sides of the electrodes facing the fuse element are provided with a notch, which possibly extends to the center of the electrode and enables an approximately central soldering of the fuse element to each electrode.

A very essential development according to the invention of the method referred to above as the second proposal is that an intermediate carrier is formed for the electrodes to be kept at a distance and for attaching the fuse element to the fuse carrier, on which the fuse element spans a loop, frame or bow-shaped extension is attached in an electrically conductive manner with both ends, whereupon the intermediate carrier including fuse element and electrodes formed or fastened on the intermediate carrier is arranged between the housing halves and the housing is closed.

In this solution, the intermediate carrier consequently forms a "lost" device with which the electrodes and the fuse element are already connected to one another and are arranged in the intended mutual position between the housing halves before they are permanently attached to one another. As will be explained with reference to various exemplary embodiments, the method according to the invention is further simplified as a result.

It is advantageous if, on both sides of the opening of the housing halves, each wing projects approximately parallel to the parting plane from the housing halves, which are cut off from the housing after the housing has been closed with the parts of the intermediate carrier lying between the wings and outside the housing and no longer used. These wings are formed in the manufacture of the thermoplastic housing halves, and within the scope of the invention they serve to center the housing halves and to accommodate the side Lich protruding loop, frame or bow-shaped part of the intermediate carrier.

There are several procedures for producing the intermediate carriers. According to a first proposal of the invention, a metal strip is formed in the form of a conductor, on the rungs of which a fusible conductor fader running transversely over this is attached in an electrically conductive manner, whereupon the intermediate carriers are separated from the metal strip along the rungs and provided with the electrodes. In this case, rectangular frame-shaped intermediate carriers result. The fusible conductor thread can firstly be attached very simply and secondly without any noteworthy waste of expensive fusible conductor material to the initially ladder-shaped metal strip, from which the intermediate carriers are then separated individually. As soon as the electrodes are soldered on both sides, the intermediate carrier is ready to be inserted into the housing halves.

As an alternative to this, the intermediate carrier according to the invention, including the contacts, can be formed from a piece of metal wire, to which a bow-shaped extension is given, at the inner corners of which the fuse element is attached in an electrically conductive manner, approximately in continuation of the outer metal wire ends. Due to this loop-shaped or bow-shaped shape of the intermediate carrier, the electrodes are automatically formed on the intermediate carrier. It is therefore only necessary to attach the fuse element to the inner corners of the bow-shaped extension so that it spans the extension freely, whereupon the intermediate carrier is ready for insertion between the housing halves.

According to a second alternative for the production of the intermediate carrier, a mixed form or combination of the two aforementioned methods for producing intermediate carriers is provided. This form of the method according to the invention is characterized in that after the attachment of a fusible conductor thread on an essentially conductor Shaped metal strip of this intermediate carrier with a second, but essentially bow-shaped metal wire intermediate carrier, the ends of which form the electrodes, is connected to one another in a electrically conductive manner to form a combined intermediate carrier, preferably welded, the first two intermediate carriers being placed one on top of the other. Here, the advantages of the first two intermediate support forms are combined.

The intermediate carrier can be completely or partially flattened. The flattening provides more stability, the round wire shape allows easier centering of the intermediate carrier between the housing halves. You can also help yourself with partial flattening.

In this embodiment, the housing halves are each closed on the front side except for a recess for the passage of the contact. Semicircular end walls are used for this, which are already standardized during the manufacture of the housing halves.

• Fig. 1 eine auseinandergezogene, isometrische Ansicht der Einzelteile einer Kleinstsicherung gemäß einer ersten Ausführungsform der Erfindung,
• Fig. 2 eine Querschnittsansicht eines zweiten Ausführungsbeispiels der erfindungsgemäßen Kleinstsicherung,
• Fig. 3 eine Querschnittsansicht einer im wesentlichen mit dem ersten Ausführungsbeispiel von _Fig. 1 übereinstimmenden Kleinstsicherung,
• Fig.4,5,6 Seitenansichten verschieden gestalteter Elektroden,
• Fi^g. 7 e.ine Querschnittsansicht durch die Elektrode gemäß Fig. 4,
• Fig. 8 eine ähnlich wie in Fig. 1 auseinandergezogene, isometrische Ansicht der Einzelteile einer Kleinstsicherung gemäß einer dritten Ausführungsform,
• Fig.9,10
• 11,12 Ansichten verschieden gestalteter Zwischenträger für die in Fig. 8 veranschaulichte Ausführungsform,
• Fig. 13,14 eine Seitenansicht sowie eine Querschnittsansicht einer Kleinstsicherung, hergestellt im wesentlichen nach dem ir. Fig. 8 veranschaulichten Verfahren,
• Fig. 15 eine Ansicht eines Metallstreifens zur Bildung einer alternativen Ausführungsform des Zwischenträgers für das durch Fig. 8-14 veranschaulichte Ausführungsbeispiel,
• Fig. 16 eine Ansicht eines zum Einsetzen in das Gehäuse fertigen Zwischenträgers, hervorgegangen aus der alternativen Ausführungsform gemäß Fig. 15;
• Fig. 17 eine Ansicht eines kombinierten Zwischenträgers.

Exemplary embodiments of the invention are explained in more detail below. The drawing shows:

• 1 is an exploded, isometric view of the individual parts of a miniature fuse according to a first embodiment of the invention,
• 2 shows a cross-sectional view of a second exemplary embodiment of the miniature fuse according to the invention,
• Fig. Is a cross-sectional view of a strength substantially identical to the first embodiment of _F3. 1 matching miniature fuse,
• Fig. 4,5,6 side views of differently designed electrodes,
• Fi ^g . 7 shows a cross-sectional view through the electrode according to FIG. 4,
• 8 is an isometric view of the individual parts of a miniature fuse according to a third embodiment, which is exploded as in FIG. 1,
• Fig. 9,10
• 11, 12 views of differently designed intermediate carriers for the embodiment illustrated in FIG. 8,
• 13, 14 a side view and a cross-sectional view of a miniature fuse, produced essentially according to the method illustrated in FIG. 8,
• 15 is a view of a metal strip for forming an alternative embodiment of the intermediate carrier for the embodiment illustrated by FIGS. 8-14.
• FIG. 16 shows a view of an intermediate carrier ready for insertion into the housing, resulting from the alternative embodiment according to FIG. 15;
• Fig. 17 is a view of a combined intermediate carrier.

The individual parts of a miniature fuse according to the invention are shown in FIG. A lower housing half 1, which consists for example of a high-strength thermoplastic, is ready to receive the inner components. These include two electrodes 3 and a fusible conductor 7, which are already combined to form a unit. After the reduction in the lower housing half 1 by means of a device not illustrated in detail here (a "lost" device ig follows from the embodiments shown in _F. 8-16), the second housing half 2 on the lower Half of housing 1 placed and heated under gentle pressure along the dividing lines, for example by ultrasound. This completes the production of a miniature fuse according to the invention.

The electrodes 3 are specially designed for a firm bond with the housing halves 1 and 2. The electrode formed by thickening at the end of a connecting wire 4 carries a circumferential V-groove 5 which produces two sharp-edged edges which are slightly larger in diameter than the inside diameter of the housing formed on the halves 1 and 2. In this way, when the housing is closed as a result of the heating of the corresponding housing sections, the sharp edges are slightly recessed into the inner surfaces of the housing halves 1 and 2, so that a very stable form-fit is obtained, which gives the miniature fuse overall good strength properties.

However, this means that the fusible conductor 7 must not be soldered to the outer edge of the electrodes 3 - here it shears when the housing halves 1 and 2 are closed, but further to the center of the electrodes 3, which is achieved in the exemplary embodiment shown with the aid of notches 6, which allow a sufficiently central attachment of the fuse element 7. For attaching the fuse element 7 to the electrodes 3, e.g. 6 Lötpaste.stricht in the notches and pressed the fuse element 7 adhering into the paste. With the help of an external heat source, the solder paste is melted, as a result of which the fusible conductor 7 is soldered to the electrodes 3.

As a result of the illustrated rotation of the two electrodes 3 relative to one another by approximately 90 °, a greater distance to the inner surface of the housing is created in the central region of the fusible conductor 7 than in the region of the notches 6; which may be important for the cohesion of the miniature fuse in the event of extreme overcurrents. The farthest Distance is achieved when the notches are arranged at 180 ° (see Fig. 3). However, the electrodes 3 should not be rotated relative to one another until the fusible link 7 has already been soldered on, since the soldering in one and the same plane is particularly simple.

When the housing halves 1 and 2 are joined together by welding, a welding lip 8 is particularly advantageous, which simplifies the welding process and almost completely changes into the plastic area during welding. Deviating from the representation of the housing halves 1 and 2 with a welding lip 8, each housing half can of course also be smooth if, for example, the intention is to glue the housing parts 1 and 2 together; in this case it is also advisable to glue the electrodes 3 into the housing. If an adhesive is used, almost any material can be used for the housing halves 1 and 2, in particular, for example, also a ceramic material or glass fiber-reinforced tube halves, which have also proven themselves as a fuse housing.

It can be seen from FIGS. 2 and 3 which form the miniature fuse has after the housing halves 1 and 2 have been closed. While in the exemplary embodiment according to FIG. 2 the fusible conductor 7 is soldered between the electrodes 3 within one and the same plane and the electrodes have subsequently not been rotated relative to one another, FIG. 3 shows an exemplary embodiment with electrodes rotated by 180 °, which leads to this that the fuse element 7 runs slightly diagonally within the housing halves. It can be clearly seen from both figures that the slight penetration of the sharp-edged electrodes into the inner surface of the housing halves 1 and 2 does not impair the fusible conductor 7, which is sufficiently centrally soldered to the electrodes 3.

FIGS. 4 and 7 show the electrode 3 used in the exemplary embodiments described above shown. It can be clearly seen that the notch 6 is only present in the section of the electrode 3 facing the fusible conductor 7, so that there is a self-contained, circumferential sharp edge towards the connecting wire 4, which edge defines the interior of the housing halves 1 and 2 completes completely. The existing between the two sections of the electrode 3 V-groove 5 allows the sinking of a tool down to the bottom of the notch 6, so that the 8 µm thin fuse element 7 can be brought to the electrodes 3 without difficulty and soldered there.

FIG. 5 shows an exemplary embodiment for an electrode 3 'in which the fusible conductor 7 is soldered to the end face of the electrode 3'.

The exemplary embodiment of an electrode 3 "shown in FIG. 6 is particularly suitable for gluing into the housing and thus also for housing halves which are glued together as intended. Again, the fuse element 7 can be soldered to the end face of the electrode 3", so that there is no danger the damage is in the vicinity of the housing wall.

In order to avoid repetitions, the two further exemplary embodiments of the invention illustrated in FIGS. 8-16 are essentially different in their differences from the embodiments of the miniature fuse as described above and illustrated in the drawings and of the production methods.

In a departure from the other exemplary embodiments, the two housing halves 1, 2 have wings 10 extending laterally from their opening, which are also molded during the production of the housing halves 1, 2. In addition, semicircular end walls 11 with likewise semicircular passages 12 for the electrodes 3. whose connecting wires 4 are provided. The electrodes 3 ₁ , like the connecting wires 4, are formed on a bow-shaped intermediate carrier 13, and the fuse element 7 spans the bow opening with fastening points by solder 14. In this fully preassembled state, the intermediate carrier 13 is brought between the two housing halves 1, 2, whereupon the two housing halves including their wings 10 are connected together in the manner already described above. Then the parts that protrude beyond the tubular shape, approximately along the dashed line denoted by 15 in FIG. 8, are cut off, namely the wings 10 and the piece of the actual bracket part 16 that protrudes outward beyond the tubular shape. This leaves what is shown in FIGS. 13 and 14 is illustrated, on both ends only one arm 17 running transversely to the longitudinal axis of the housing, which contributes to the centering and stabilization of the fuse. '

There are a number of possibilities for the design of the intermediate carrier 13, which are shown in FIGS. 9-12. The cross section of the intermediate carrier 13 can be left round throughout (FIG. 9). But you can also flatten the actual bracket part 16 'to give it more stability, to achieve a larger and essentially flat surface for the fastening points by solder 14 and to ensure easier insertion of the intermediate carrier 13 also in the area of the wings 10 , while the round cross-section of the connecting wire 4 or the appropriately designed start of the electrodes 3 _1, which is suitable for centering in the longitudinal direction of the housing, is still retained (FIG. 10). Instead of flattening the entire bracket 13, it is also possible to restrict to the corner area of the bracket and the arms 17 which extend outward, as shown in FIG. 11. A completely flattened version of the intermediate carrier 13 according to FIG. 12 is of particular stability. In this case, a passage opening on the end walls 11 adapted to this cross section must be provided for the purpose of clear fixation.

15 and 16 show a modified embodiment of the bracket. First, a ladder-shaped metal strip 18 is punched out, over which, as shown, a fusible conductor wire 19 is guided and fixed to the rungs 21 of the metal strip 18 by means of solder 20. Thereafter, the intermediate carriers 13 'are continuously separated from the metal strip 18 along the rungs 21 or the lines 22 shown in broken lines. After the connection wires 4 have been soldered on to the fastening points of the fusible conductor 7 acting as electrodes 3 ₂ , the intermediate carrier 13 ′ is fastened between the housing halves 1, 2 provided with wings 10 in the same way as the previously described intermediate carrier 13 (see FIG. 8). . Then again the wings 10 are separated from the tubular housing, and at the same time the actual bracket parts 16 'projecting on both sides are also cut off along the dashed line 23, so that in this embodiment, in contrast to that shown in FIGS. 13, 14, it extends to both sides Arms remain in the fuse (designated 17 in Fig. 13, 14) and fix the electrodes 3 ₂ and the fuse element 7. In this respect, the two embodiments according to FIGS. 9-14 on the one hand and FIGS. 15 and 16 on the other hand essentially differ only in the different shape and production method of the intermediate carrier 13.

The third embodiment of an intermediate carrier 13 ″ shown in FIG. 17 is a mixed form, which consists of an intermediate carrier 13 and an intermediate carrier 13 ′ placed thereon and preferably electrically welded and fastened thereon. On the latter, the fusible conductor 7 has already been fastened in the manner described above before the metal strip 18 is divided, and the connecting wires or contacts 4 extend on both sides after the intermediate carrier 13 has been formed from a piece of metal wire. After the introduction of the intermediate carrier 13 "into the two housing halves 1 and 2 (not shown) also takes place in the miniature fuse type produced in this way according to the invention, the cutting of the wing 10, not shown, and the protruding bracket parts 16, 16 ¹ . The arms 17 remain in the miniature fuse, they extend at each of the two fuse ends approximately radially on both sides, always in duplicate on one side, namely as a piece of metal wire with a piece of sheet metal attached to it. This embodiment has a particular stability with good centerability, and it is possible to avoid soldering the connecting wires or electrodes 4, as shown in FIG. 16, to the side.

Claims (19)

1. A method for producing a miniature fuse, in which, after fixing the distance between two connecting electrodes, a fusible conductor is fastened between them in an electrically conductive manner and then an initially two-part housing made of insulating material, which surrounds the electrodes and the fusible conductor, is closed, characterized in that the housing the inside is formed essentially smooth, that the spaced electrodes are pre-attached in one housing part, and that after the fuse element has been fastened, the housing is closed with the electrodes finally being attached to the inner surface. 2.Method for producing a miniature fuse, in which, after fixing the distance between two connecting electrodes, a fusible conductor is fastened between them in an electrically conductive manner and then an initially two-part housing made of insulating material, which surrounds the electrodes and the fusible conductor, is closed, characterized in that the housing ^- is formed on the inside essentially smooth surface that the fusible conductor is attached between the spaced electrodes and that the electrodes are placed together with the fuse element in one housing part and the second housing part is placed thereon for fixing the electrodes and the fuse element and for closing the housing. 3. The method according to claim 1 or 2, characterized in that a housing made of thermoplastic is selected and that the pre-attachment by heating the electrodes and partially pressing them into the inside of the housing and closing the housing by heating the parting line and compressing the housing parts becomes. 4. The method according to one or more of claims 1 to 3, characterized in that the outer diameter of the electrodes is chosen to be larger than the inner diameter of the closed housing and that when the housing is closed the part of the electrodes which was previously uncovered is pressed into the inside of the housing becomes. 5. The method according to claim 2, characterized in that the fuse wire is soldered substantially axially parallel to the common central axis of the electrodes and the electrodes are rotated by a predetermined angle, in particular about 180 ° C against each other before insertion into the one housing part. 6. The method according to claim 2, characterized in that an intermediate carrier is formed for the electrodes to be kept at a distance and for fastening the fusible conductor to this, on which the fusible conductor spans a loop, frame or bow-shaped extension with both ends electrically conductive is attached, whereupon the intermediate carrier including fuse element and electrodes formed on or attached to the intermediate carrier between the Housing halves arranged and the housing is closed. 7. The method according to claim 6, characterized in that on both sides of the opening of the housing halves each wing project approximately parallel to the parting plane of the housing halves, which after closing the housing with the lying between the wings and outside of the housing and no longer used parts of the intermediate carrier be cut off from the housing. 8. The method according to claim 6 or 7, characterized in that for the production of the intermediate carrier a metal strip is formed in the form of a ladder, on the rungs of a fusible conductor wire running across this is electrically conductively attached, whereupon the intermediate carrier of the metal strip along the rungs divided and provided with the electrodes. 9. The method according to claim 6 or 7, characterized in that the intermediate carrier including the contacts is formed from a piece of metal wire, which is given a bow-shaped extension, at the inner corners of which, in continuation of the outer metal wire ends, the fuse element is fastened in an electrically conductive manner. 10. The method according to claim 9, characterized in that the intermediate carrier is completely or partially flattened. 11. The method according to one or more of claims 6 to 10, characterized in that the housing halves are closed on the end face and provided with a recess for the passage of the contact. 12. The method according to one or more of claims 1 to 11, characterized in that the pre-fastening or the closing of the housing is effected by gluing or welding. 13. The method according to one or more of claims 1 to 12, characterized in that the housing is formed from two substantially identical tube halves. 14. The method according to one or more of claims 1 to 13, characterized in that a weld lip is formed on each housing part at the one seam and that when the housing is closed, each seam with a weld lip is paired with one without a weld lip. 15. The method according to one or more of the preceding claims 6 to 14, characterized in that after the attachment of a fusible conductor thread on an essentially ladder-shaped metal strip, the intermediate carrier separated therefrom with a second, but essentially bow-shaped intermediate carrier formed from metal wire, the ends of which form the electrodes, connected to one another in an electrically conductive manner to form a combined intermediate carrier, preferably welded, the two first-mentioned intermediate carriers being placed one on top of the other. 16. Miniature fuse, consisting of a housing composed of two parts with electrodes held therein, on which there are connecting wire ends on one side and a fuse element is attached on the other side, characterized in that the housing (1, 2) is tubular and on its inside is essentially smooth and that the electrodes (3) close the end faces of the housing (1, 2) like a stopper. 17. Miniature fuse according to claim 16, characterized in that the outer edges of the electrodes (3) are sharp-edged and are slightly pressed into the housing wall. 18. Miniature fuse, consisting of a two-part housing with electrodes held therein and electrically conductively connected to one another by a fusible conductor, characterized in that the housing (1, 2) is tubular and has an essentially smooth surface on its inside and on both ends except for a passage (12) for the respective contact (3 ₁ , 3 ₂ ) or for the respective connecting wire (4) and inside the front with at least one in each case transverse to the longitudinal axis in the division plane, optionally up to the outside of the housing, and with the there Contact (3 ₁ , 3 ₂ ) connected or one-piece arm (17) is provided. 19. Miniature fuse according to claim 18, characterized in that at least one arm (17) on each side of a piece of metal wire, from which the adjacent connecting wire (4) is angled, and consists of a piece of sheet metal connected to it in an electrically conductive manner, at one end of the fuse element (7) is attached in an electrically conductive manner.

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