DE239840C - - Google Patents

Description

IMPERIAL

PATENT OFFICE.

PATENT LETTERING

- JVi 239840 CLASS 21 c. GROUP

Dr. MARTIN KALLMANN in BERLIN.

Patented in the German Empire on July 26, 1910.

The use of variation ladders, especially iron wire with its high positive Temperature coefficients, enabled in parallel to the main fusible conductors it, relatively small fuses explosion-proof even for voltages of 500 volts to manufacture. Such fuses can have very different shapes, such as glass or porcelain tubes in asbestos Embedded fusible conductors, flat fuses, which are mainly pressed between mica are, and other strip and socket locks or flexible ones drawn into cords and the like Fuses etc.

Of course, the common fusible links can also be made according to the Edison system or with eyebolts or two-part locks with Edison or other threads and . train special melt cartridges as protection against variations. The considerable reduction in the explosive force of the Melting of the wires as a result of the use of two successive, weakened ones However, melting processes make porcelain or other insulating walls as strong as those used in conventional fuses wont to be required. Rather, one is applying the variator principle able to use relatively small dimensions of the fuses even for higher ones ■ to maintain tensions, e.g. B. Edison plugs, which otherwise only short-circuit 125 volts would be tolerated to use for voltages of 440 volts.

The execution is done according to FIGS. 1 and 2 in such a way that the interior of the plug 5 divides by a partition 6, which also consists of an inserted mica or porcelain disc can exist. The silver, lead or other fusible wire 4 is brought into the chamber, which is usually larger other chamber the iron wire 7, z. B. a silver wire 4 cm long and 0.25 mm Thick and parallel to it an iron wire 15 cm long and 0.25 mm thick. One can one conductor on one side, the other on the opposite side of the Solder thread 3 so that the ends of the two are separated as far as possible. Of the Iron wire 7 is expediently easily evaporated with a zinc coating or some other provided the coating in order to avoid clearly visible precipitates or To achieve colorations. The beginning of both conductors is at the common ground contact 2 fastened and tends to be plastered up to a certain height. Also the end fixings Maintain the two conductors at the soldering points of the thread in the known manner to be sealed with plaster of paris.

However, one can observe that even with the small Edison plugs for about 250 volts no such seals to prevent explosions, standing fires, flashes of flames and the like are required, but that the mere filling of the cavity with sand, Emery or other filler material is sufficient to completely remove any major explosive effect to . suffocate. The making of such conclusions is, albeit, the ladder of variation Added to that, quite simply due to the elimination of more careful seals. At higher

However, the sealing and partial pouring is also recommended for tension with plaster ο. like

The iron wire, because of its greater length, must as a rule be wound up in a spiral shape in order to find space in my chamber; however, its flames are completely suffocated by the filler material.
In addition, the iron wire is suitable, the

ίο to replace otherwise usual identification wire, since he finally melts and has great strength. You can do this very easily. B. according to Fig. Ι and 2 make in such a way that you have a short piece of iron wire, of about ι cm in length, can protrude from the filling material and an asbestos disc is appropriate underlaid it, which on the one hand should cover the interior of the melting plug, on the other hand serves to make the iron wire stand out more clearly. That visible bit Iron wire is, as usual, through the cover 1 of the plug, which has a peephole and a Glass pane, a mica window or the like. Is provided, optionally with an intermediate layer completed by mica. So you can see the piece through the window in the lid Iron wire; after melting through, whereby this piece also becomes glowing and If its zinc coating, if any, evaporates, a black spot or another clear indicator of the melting through. The lid seal As experience has shown, the ordinary Edison plug is completely sufficient for to prevent iron parts from being thrown around.

You can also arrange the space in the plug almost completely for the silver wire to use the iron wire connected in parallel completely or for the most part z. B. wound flat on a plate made of mica 0. if necessary, protected by asbestos, placed above and through the lid

z. B. presses onto the filler material. He can also do this through a window in the lid be made visible.

You can also, as is the case with some fusible plugs, several holes that Are separated by porcelain walls 0. The like, use for the variation safeguards by one in one hole the silver wire, in the other the iron wire, z. B. in spiral form, put in and fill everything with filler material. You can also do multiple backups manufacture conveniently in this way; z. B. with six holes would be used three times possible, as two holes are needed each time for a fuse.

According to the invention, fuses of the type described can thereby be made particularly simple be made that you have the fuse wires in the form of a special, easily replaceable Produces insert body, which is arranged in the cavities of the fusible link -, is net. This insert body consists of the connected in parallel, through. Coatings, like protective tubes, separate from one another, but because of the reduced explosion effects not further sealed main and variation ladders. Those made of kaolin or the like can serve as protective tubes, which are slipped over the silver wire and onto which the iron wire is attached Is wound spirally.

In Fig. 3, an embodiment of such a fuse with main and variation conductors for Edison plugs is shown, which at analogous modification also for two-part fuses as well as for tube or any other designed fuses applies.

Here is the silver wire 4 in a tube 12 ζ. B. made of kaolin and is to the Foot contact 2 and the thread 3 connected. The iron wire is on the tube 12 7 wound or otherwise arranged around the same or housed next to the same in a suitable manner, so that the Pipe wall forms the contactor between the two fusible conductors. The silver wire 4 ends at the top at the contact 9, which is in communication with 3, while the iron wire 7 after it through the asbestos discs 10 and 11 under the Window of the cover 1 is passed, to the contact also connected with 3 8 leads. The free space is filled with filler material 6.

One obtains in this way quickly repairable fuses, since an insert body like z. B. that shown in Fig. 3, from an inside containing the silver wire, outside the iron wire The existing tube is very easy to replace due to the elimination of difficult seals and the ends of the two Fusible conductors can easily be screwed back onto the contacts. ■

At low voltages, such fusible plugs are even without filling material themselves can be used in the event of a short circuit.

With regard to the fact that only an extremely small filling space of a few Millimeters in diameter and only very thin walls are required for variator safeguards , Edison fuses with a Mignon thread and similar small ones can of course also be used Apply shapes even for higher tensions.

A protective layer or protective distance is always required around the variation ladder to protect against the melting flames of the main conductor so that it is not destroyed prematurely. This protective layer can be limited to those points at which the

refractive flames occur, ζ. B. when it can be expected with certainty that not the whole executive melts away.

In addition, the protective layer can be provided by walls made of porcelain or the like or by coatings of insulating tubes over the fusible conductors or through intermediate layers of porcelain, glass, mica, asbestos or other solid insulating material or by wrapping the wires

ίο be established, or you limit yourself only on sufficient layers of filling material made of sand and the like, or on one sufficient Distance between both conductors. In some cases, you can also create very simple shapes and protective layers using melting plugs usual pouring with plaster ο. like. Achieve.

Claims (1)

Patent claim: Electrical fuse with main and variation conductors, characterized in that in the cavities of the fusible link (screw plug, cartridge, etc.) special, easily replaceable insert body is arranged, which from the parallel switched, but not separated from one another by coatings (e.g. protective tubes) further sealed main and variation conductors, whereby the variation conductor can be used as a reference wire. 1 sheet of drawings.