JP2538244B2 - Leakage transformer for discharge lamp - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a protection system for a leakage transformer for a discharge lamp, which is discharged from an AC power source for safety reasons when it is out of order or has a life. It shuts off the leakage transformer for electric lights.

[Conventional technology]

For example, as described in Japanese Examined Patent Publication No. 61-29130, there is a ballast for a discharge lamp in which the oil insulating film has a two-layer structure of a polyester film layer and a nylon film layer, and the entire film has an appropriate low temperature melting property. Are known.

When this ballast fails or reaches the end of its life, an interlayer short circuit occurs, its impedance decreases, and the energizing current increases, and the coil is conveniently disconnected. This ballast is of the so-called choke coil type, not of the leakage transformer type.

[Problems to be solved by the invention]

The leakage transformer for a discharge lamp includes a primary coil connected in parallel with an AC power source, and a secondary coil connected in series with the primary coil and the discharge lamp. Even if the insulating coatings of the primary coil and the secondary coil are made of a low-temperature-melting material, the primary coil and the secondary coil are not always disconnected at the same time or before and after the same. When only the primary coil is broken, power is supplied to the discharge lamp through the remaining secondary coil. If only the secondary coil is broken, the exciting current is still supplied to the primary coil.

As described above, the leakage transformer for the discharge lamp, which has failed or has reached the end of its life, is partially and continuously operated, which is not preferable from the viewpoint of safety and the knowledge of preventing power loss. An object of the present invention is to eliminate the above problems.

[Means for solving problems]

The present invention includes a primary coil connected in parallel with an AC power supply,
It is assumed that the discharge transformer for a discharge lamp is equipped with a secondary coil connected in series with the primary coil and the discharge lamp. An auxiliary coil is connected in series to the circuit connecting the primary coil and the terminal of the AC power supply. The auxiliary coil is wound around a coil winding frame of either a primary coil or a secondary coil. Moreover, the insulating film of this auxiliary coil is a low temperature melting thing. Low temperature melting itself is well known and its temperature is set so that the insulating coating melts before the coil smokes or burns. Further, the auxiliary coils are wound so that at least some of them come into contact with each other. An example of such winding is irregular winding, but the same effect can be obtained even with aligned winding.

[Action]

The auxiliary coil normally functions as part of the primary coil. Further, the auxiliary coil acts as a transformer with the primary coil or the secondary coil wound on the same winding frame.
This transformer action does not particularly contribute to the lighting of a normal discharge lamp, and does not affect it. When the leakage transformer for the discharge lamp fails or reaches the end of its life, the primary coil or the secondary coil overheats. Therefore, the auxiliary coil is also overheated, and its insulating film is rapidly deteriorated. Under this circumstance, the auxiliary coils are short-circuited to each other and at least one closed circuit appears in the auxiliary coil. At this time, a large current flows in the closed circuit due to the action of the transformer, and the part of the closed circuit melts and disappears. As a result, the closed circuit portion of the auxiliary coil is locally disconnected, and the AC power source and the discharge lamp leakage transformer are opened.

〔Example〕

Hereinafter, one embodiment shown in FIGS. 1, 5, and 6 will be described. In the figure, 1 is a primary coil and 6 is a secondary coil. Together with the iron core 93, these are the main components of the leakage transformer for discharge lamps. This transformer includes an auxiliary coil 3. Also included are cases 94, compounds and the like. The iron core 93 also includes a leakage path 93 '. 7 is a discharge lamp (fluorescent lamp), 99 is a blow starter, and these are parts outside the transformer.

One connection 2 of the primary coil 1 is connected via an auxiliary coil 3 to one terminal 4 for an AC power supply 11. The other connecting portion 5 of the primary coil 1 is the other AC power source 11
It becomes a terminal. The connecting portion 5 of the primary coil 1 and one connecting portion 5'of the secondary coil 6 are connected by a crossover wire. The discharge lamp 7 is connected between the one connecting portion 2 of the primary coil 1 and the other connecting portion 8 of the secondary coil 6. Glow starter
99 is connected between the non-power supply terminals of the discharge lamp 7.

As described above, the AC power supply 11 is connected in parallel with the primary coil 1 via the auxiliary coil 3. The secondary coil 6 is connected in series with the primary coil 1 and the discharge lamp 7. The winding direction of the primary coil 1 and the auxiliary coil 3 or the manner of connection is additive, and they are wound on the same winding frame 10 as shown in FIG. On the other hand, the coil 1 and the auxiliary coil 3 as a whole have a primary coil portion 91 (FIGS. 5 and 6) that acts as the same primary coil.
It is not a mistake to think that one end of the discharge lamp 7 is connected to the tape 2 near the terminal 4 as shown in FIG.

In FIG. 6, for the sake of convenience, a circle represents the primary coil 1
And the double circled line is the auxiliary coil 3. Auxiliary coil 3
Is wound on the outer peripheral side of the primary coil 1, but this may be the inner peripheral side or the intermediate layer. In this embodiment, the auxiliary coil 3 is wound closely and closely over two layers, and the area of contact between the coils 3 is large.
Although this contact area (contact point) is small, it is also possible to carry out so-called irregular winding, and the point is that the auxiliary coils 3 need to be in contact with each other (at least two locations). Further, when the upper and lower two layers are provided, they may be aligned-spaced windings in which they are aligned and wound while maintaining a space.

The insulating film 3 '(FIG. 7) of the auxiliary coil 3 is of low temperature melting property. For example, polyurethane insulation film 3 '
Is. Further, a nylon overcoat polyester film (two-layer structure) 3'may be used. Furthermore, it is possible to use a nylon overcoat polyurethane film (two-layer structure) 3 '. In any case, this insulating film 3'melts before the leakage transformer overheats and smokes or burns,
It has a melting concentration of 20
It is 0 to 250 ° C.

In the embodiment shown in FIGS. 1, 5, and 6, the auxiliary coil 3 functions as the primary coil portion 91 together with the primary coil 1. When the leakage transformer overheats, the insulating film 3'starts to melt. Along with this, one or a plurality of closed circuits appear everywhere in the auxiliary coil 3. This open circuit acts as a transformer with the primary coil 1 as the other party, and an excessive current flows to melt it at the moment. On the other hand, if the melting does not occur here, overheating of the closed circuit prompts the appearance of another closed circuit adjacent to the closed circuit, which is a kind of avalanche phenomenon. If any one of the closed circuits melts and the part of the auxiliary coil 3 where the closed circuit existed is lost, a kind of disconnection occurs and the power supply from the AC power supply 11 to the primary coil 1 is stopped. Also,
The current flowing from the AC power supply 11 to the secondary coil 6 and the discharge lamp 7 is also stopped, and further overheating of the discharge lamp leaky transformer and power consumption are prevented.

In the embodiment shown in FIG. 2, the auxiliary coil 3 is arranged on the side of the connecting portion 5 which has already been pointed out, and this has the same effect. In the embodiment shown in FIG. 3, the auxiliary coil 3 is replaced by the secondary coil 6.
It is wound on a reel outside the drawing on the side of. In the embodiment of FIG. 4, the auxiliary coil 3 arranged on the side of the connecting portion 5 is wound around the winding frame on the side of the secondary coil 6.

In any of the above embodiments, the auxiliary coil 3 functions as a sensor for detecting overheating of the primary coil 1 or the secondary coil 6. The spread of the auxiliary coil 3 substantially coincides with the detection range. Also, when overheating is detected, it functions as a current fuse that fuses the current from itself by the action of the transformer and fuses it.

〔The invention's effect〕

As described above, according to the present invention, the auxiliary coil having the low temperature melting insulating film connected between the primary coil and the terminal of the AC power source is wound around the winding frame such as the primary coil in a predetermined manner. According to this, it is possible to stop all operations of the leakage transformer for the discharge lamp at the end of life, ensure safety, and prevent useless power loss.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an embodiment of the transformer of the present invention, FIGS. 2 to 4 are similar circuit diagrams showing different embodiments, and FIG. 5 is a transformer of the circuit shown in FIG. A sectional view, FIG. 6 is an enlarged view showing a sectional view of the primary coil portion thereof. In the figure, 1 is a primary coil, 3 is an auxiliary coil, 3'is an insulating film, 6 is a secondary coil, 7 is a discharge lamp, and 11 is an AC power supply.

Claims (8)

(57) [Claims] 1. A leakage transformer for a discharge lamp, comprising: a primary coil connected in parallel with an AC power supply; and a secondary coil connected in series with the primary coil and the discharge lamp. Auxiliary coil is connected in series to the circuit connecting, the auxiliary coil is wound on one of the coil winding frame of the primary coil and the secondary coil, and the insulating film of the auxiliary coil is of low temperature melting property, A leakage transformer for a discharge lamp, characterized in that an auxiliary coil is wound so that at least parts thereof are in contact with each other. 2. A connection point between the primary coil and the secondary coil,
The leakage transformer for a discharge lamp according to claim 1, wherein an auxiliary coil is connected in series with one terminal of the AC power supply. 3. The leakage transformer for a discharge lamp according to claim 1, wherein the auxiliary coil is wound around the coil winding frame of the primary coil. 4. The leakage transformer for a discharge lamp according to claim 1, wherein the insulating film of the auxiliary coil is made of polyurethane. 5. A leakage transformer for a discharge lamp according to claim 1, wherein the insulating film of the auxiliary coil is composed of a polyester film layer on the wire and a nylon film layer on the outer periphery thereof. 6. A leakage transformer for a discharge lamp as claimed in claim 1, wherein the auxiliary coil is wound in such a manner that at least some of the auxiliary coils come into contact with each other. 7. The leakage transformer for a discharge lamp according to claim 1, wherein the auxiliary coil is wound in two layers in the upper and lower layers. 8. The leakage transformer for a discharge lamp according to claim 1, wherein the connection relationship between the primary coil and the auxiliary coil is polarized.