DE1157292B - Hot wire switch - Google Patents

Description

The invention relates to a hot wire switch with a hot wire, the fixed clamping end of which is held insulated by a glass drop and is used for power supply. Such switches are in particular for automatic control of the switching of the turn signal light in vehicle direction indicators used.

In hot wire switches, it is often necessary to attach one end of the hot wire so that it is isolated from the other parts of the switch. This is generally caused by the resistance wire, from which the hot wire is made, runs through the glass drop and that this glass drop is attached to the wire, with the part of the resistance wire on one Side of the drop forms the tensioned hot wire and the part of the resistance wire on the other Side of the drop serves as a resistance feed line to the hot wire. The glass drop is im melted or soft state, shrunk or pressed onto the wire, and about the pulling out to prevent the wire through the glass drop, the wire line that leaves the drop, clamped in an eyelet or attached to a corresponding part that is too large to be it can be pulled through the drop. There is a risk that the hot wire after repeated heating and cooling pull something out of the drop. Nice a slight movement of the anchored wire end is sufficient to z. B. the turn signal ratio so too change that the flashing lights no longer work within the limits stipulated by law are.

The object of the invention is now to improve the previous construction so that the the aforementioned disadvantages can be reduced or eliminated. To this end, according to the invention suggested that a wire supplying the current should be at or near the same point of the Drop from which the clamped hot wire extends to its movable clamping point, establishes the current transfer to the clamped hot wire. As a result, the parts of the wire or the wires on which the glass gob is attached are less heated than in the earlier designs is the case where all of the current flows through the wire running through the drop, with the result that it is now much less likely that the Wire loosens in the glass drop due to the repeated heating and cooling of the hot wire.

Applicant:

William Edward O'Shei,
Harlington, Middlesex (UK)

Representative: Dr. H. Wilcken, patent attorney,
Lübeck, Breite Str. 52/54

Claimed priority:
Great Britain dated November 28, 1960 (No. 40 813)

William Edward O'Shei,

Harlington, Middlesex (Great Britain),

has been named as the inventor

Although the hot wire and the lead wire may be separate wires that are electrically connected to each other are connected, as mentioned above, they are advantageous according to a feature of the invention from a continuous length of resistance wire, the part of the wire that is in the Glass drop is to be attached, laid as a loop or bent back against itself and thereby forms a double wire, the glass drop then being attached to this double wire in this way is that the part of the wire which serves as the power supply line to the hot wire comes from the same end of the drop protrudes like the hot wire part. Since the bent loop or loop parts of the The wire are pressed together by the glass drop and are thus protected against oxidation, the current to the hot wire flows mainly through the interface between the two Wire parts near the hot wire end on the drop, and negligible current flows through it loop-shaped double wire part, which is surrounded by the glass drop. This will make the wire in the Droplet is less heated than before, and as a result it is less likely to be in the In contrast to the previous structure, the glass drop releases the full current with every switching cycle flows through the wire that runs through the drop.

309 748/307

To improve the grip of the glass drop on the double wire, the two can Strands are twisted, knotted or deformed so that the glass drops on the Twisting, knotting or deformation of the double wire is attached. If the The hot wire and the lead wire are separate wires, they can be twisted together in a similar manner or knotted, and the glass drop is tied on the twisted or knotted part ίο with both wires protruding from the same end of the glass gob.

To make the invention more understandable, it will now be based on an embodiment of the Drawing explained, namely shows

Fig. 1 is a side view of an embodiment of a flasher unit according to the invention with a section the case,

FIG. 2 shows an enlarged section through part of the embodiment according to FIG. 1.

According to the drawing, the flasher unit consists of two anchors 14 and 15 made of magnetic material, which are arranged so that they are attracted by the pole pieces 8, 8 a and 9, 9 a of a magnetizable core 1, which is provided with a waist part which an excitation winding 7 is wound. The armature 14 is held at a distance from the pole pieces 8, 9 against the action of a spring 20 to which it is attached, which presses on a stop 12 and which is connected to a length of resistance wire which has a hot wire 22 or forms a wire 22 elongated by heat. One end of the hot wire is held in a fixed position in a glass drop 23 which engages in a bore 24 of an ear 25 which is bent outward from a part 21. The other end of the hot wire 22 is fastened to the free end of the armature 14 by means of a rivet 26.

The arrangement is mounted on an insulated base 4, which is provided with contact pins for switching on the Device is provided in a circuit, and the arrangement is in a metal container or a Housing 32 housed.

As shown in detail in Fig. 2, the portion of the resistance wire that is in the glass gob 23 is attached, laid in a loop or bent at 40 against itself to double it To form wire, the two strands being twisted three or four times with one another, as indicated at 41 is so that the bent back portion of the resistance wire is from the same end of the drop protrudes like the hot wire part 22 and serves as a power supply line 42 to the hot wire. The lead wire 42 makes electrical connection to hot wire 22 at or near the end of the drop 23 from which the hot wire runs away. During the manufacture of the device, the glass drop 23 to a certain extent threaded over the two wires and on the other hand abuts against the Loop 40. The glass drop 23 is heated and shrunk around the twisted turns.

The lead wire 42 has a helically wound portion 43 (Fig. 1) around the lead wire to give a suitable length and thereby to form the required series resistance, and is connected to a contact 16. The coil part can therefore on a sleeve 44 made of electrically insulated Material are wound, which engages around a conductor wire between the contact pin and a contact 17 is connected, which in connection with the armature 15 the circle of a Control light controls. This conductor has sufficient rigidity around the wound part 43 sufficiently mechanically supported and so to hold it in its position, so that no short circuits occur against the housing 32 or against any parts.

Claims (3)

PATENT CLAIMS: 1. Hot wire switch with a hot wire whose stationary clamping end is held insulated by a glass drop and is used for power supply, characterized in that a wire (42) supplying the current at or near the same point of the drop (23) from which the clamped hot wire (22) extends to its movable clamping point (26), which produces the current transfer to the clamped hot wire. 2. Switch according to claim 1, the hot wire and power supply of a one-piece resistance wire consist, characterized in that the part of the wire which passes through the glass drop is attached, looped or bent back against itself and that the glass drop is attached to the doubled piece of wire. 3. Switch according to claim 2, characterized in that the two strands of the double Wire are twisted, knotted or deformed and that the glass drop on the Twisting, knotting or deformation of the double wire is attached. Considered publications:
German utility model No. 1812146;
U.S. Patent No. 2,715,187. For this purpose, 1 sheet of drawings © 309 748/307 11.63