SU69364A1 - High voltage fuse - Google Patents

Description

The fuses with quartz sand as a filler are distinguished by effective damping of large currents, silent operation and simplicity of design.

However, the known constructions of such fuses (with fixed fusible elements) do not provide effective extinguishing of small currents, and at average values of currents they have a critical non-disconnection zone, if their fusible element is not arranged in a special way.

Another disadvantage of fuses with stationary fusible elements is the use of a large number of parallel-connected thin and long fusible wires (sometimes more than 20 pcs.), As a result of which the cartridge becomes bulky and heavy, and the process of recharging and servicing it is significantly complicated.

Among the fuses with movable fusible elements, high-voltage fuses are known, in which the wire melted from mechanical drawing is located in quartz sand and

and Code in. 9

sprained. The springs intended for pulling out the ends of the destroyed melting wire and forcing the arc into quartz sand can be held in tension by a wire pull, shunt the fuse wire and being destroyed when the latter is burned.

The present invention relates to such structures of high-voltage fuses and consists in a special form of their implementation, the distinctive feature of which is that, in order to ensure reliable quenching of the train, regardless of the magnitude of the current, the ha is divided by an iso-routing insert located at the weakened section of the fusible wire in this way that when the latter is melted, a spark occurs on the insertion, which burns out.

The invention is illustrated in the drawing. FIG. I shows a cut through the fuse and in FIG. 2 and 3 are two projections of the fusible wire attachment assembly on the insulating insert. During normal operation, the current is 161

It goes, for example, through the contact / (when installed it is upper), cap 2, screw 3, in parts of the melting wire 4-5-6, screw 7, left (lower) cap 8 and contact 9.

Parallel to the fusible wire 4-5-6, there is a mechanically strong ha, perceiving the tension of the spring 10. The ha consists of two parts 77 and 72, one of which passes through the inner hole of the insulating insert 13 and is fixed into the loop, and the other covers the insulating box 13 on the zholobku on its outer surface. Thus, the loops of the parts 11 vi 12 t gi are located in mutually perpendicular planes, are not electrically connected to each other and are separated by a small spark gap. The weakened fusible wire section 5 is arranged parallel to the spark gap.

The process of triggering the fuse begins by melting the weakened section 5 of the melting wire. After that, an electric arc appears along the insulating insert 13 between the parts 77 and 72 tons of force. The arc burns through the loop of one of the parts of the rod, which, under the action of a spring, is drawn through quartz sand to the other end of the cartridge.

The flexible connection of the fusible wire with the screw 7 ensures that the fusible wire is drawn almost to the full length of the cartridge. The presence of a weakened area of the fusible wire ensures a burnout in a pre-fixed place, at all values of the current to be switched off, since in the presence of a current-carrying fusible wire, the ha is almost not heated by the current and burned out by an arc only in the spark gap.

The current-carrying element of the fuse can be made in the form of a single wire with a weakened section of the corresponding section for all values of the rated current.

The cartridge of the proposed safety device has small dimensions, its recharging and maintenance in operation are rather simple.

The subject of the invention A high-voltage fuse, in which the melted wire unloaded from a mechanical pull, is located in quartz sand, and the springs, designed to pull out the ends of a broken melted wire and draw the arc into quartz sand, are held in tension by a wire drawn bypassing fusible wire. and destroyed during combustion of the latter, characterized in that, in order to ensure reliable extinguishing of the arc regardless of the magnitude of the current, t ha is divided by an isolating insert, located in the weakened region of the fusible wire in such a way that when the latter is melted, a spark occurs at the insertion that burns.

FIG. one