JPS5834898B2 - high pressure discharge lamp - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a high pressure discharge lamp having a fuse in the lead wire of the lamp which requires a separate ballast, and more particularly relates to a high pressure discharge lamp which requires a separate ballast and has a fuse in the outer tube of the lamp. In a lamp in which a stem with two power supply lead wires is sealed and evacuated and then a cap is attached, one of the lead wires is connected to the cap shell, the other to the eyelet of the cap, and the side that connects to this eyelet. The present invention relates to a high-pressure discharge lamp characterized in that a fuse that melts at a current exceeding the rated current, such as a consonant wire, is attached to a part of the lead wire.

Generally, in discharge lamps that require a ballast, no current greater than the secondary short-circuit current of the ballast flows, so no fuse has ever been installed in the lamp.

In recent years, mercury lamps with built-in ballasts and general high-pressure discharge lamps that require ballasts are sometimes used in the same appliance. There are cases where it is unclear whether a ballast is connected to a circuit just by looking at it.

In particular, if the shape of the lamp is the same as one that requires a ballast, a situation may occur in which a lamp that requires a ballast is mistakenly attached to the circuit of a lamp with a built-in ballast.

In some cases, the rupture of this arc tube may cause damage to the outer tube.

It cannot be said that there is no risk of injury to the lamp remover.

The present invention has been devised to ensure absolute safety against the above-mentioned hazards, and will be explained below with reference to the drawings.

Figure 1 shows a fixture 4 directly attached to the ceiling 3 for indoor lighting, etc.
If the power supply circuit 1 is installed in the attic, it is unclear whether a ballast is installed in the attic just by looking at the appliance 4, and even if there is a label on the appliance etc. Even if a display is provided, the display may become dirty and unclear by the time the lamp is replaced.

If a lamp 5 that requires a ballast of the same shape is attached to a circuit that does not have a ballast installed, the above-mentioned accident will occur, which is an extremely important safety problem.

FIG. 2 provides safety measures for the lamp itself in response to this, and the lamp envelope 5 is an envelope for a lamp that requires a ballast of the same shape as a lamp with a built-in ballast. is supported by the support metal fittings 7 and 7', and the support metal fitting 7
, 7' are connected to lead wires installed in the steam 8.

Two lead wires 9 and 9' are connected to the stem 8, one lead wire 9 is connected to the shell side of the base 10, and the other lead wire 9' is connected to the eyelet 12 side of the base 10. It is connected.

The lead wire 9 contacts the stem 8 and is guided to the outside of the shell along the stem 8 for connection. Therefore, if a fuse is provided on the lead wire 9 side, the heat generated when the fuse blows will cause the stem 8 to There is a risk that the outer tube 5 may be damaged or ruptured.

When the fuse is connected to the lead wire 9' side, this risk does not occur because the lead wire 9' does not come into direct contact with the stem 8.

In order to further improve safety, the lead wire 9' provided with the fuse may be covered with a glass wool tube 14 or the like.

Note that 11 in FIG. 2 indicates an insulating part of the base.

An arc tube 6 of a 200 watt high-pressure mercury lamp is mounted on a spherical envelope tube 5 with a diameter of 150 mm, and a large group of lamps with no fuses connected to the lead wires 9 and 9' and a lead wire 9 are constructed. Lamp C with a fuse on the side
Group, lamp C with a fuse on the lead wire 9' side
As a result of applying power to three types of groups using circuits without a ballast, the lamps in Group A were found to have ruptured on 8/10 due to the rupture of the sealing part of the arc tube; 2/8 where the surrounding tube 5 was damaged 2/8 where the molybdenum foil inside the sealing part was only melted 2/
It was lO.

In Group B, 4/10 cases had damage to the stem 8, 1/4 cases had damage extending to the outer tube, and 6/40 cases had simply blown fuses.

In the case of group C, all the LO/lO fuses were blown, and no damage was observed to the stem 8, the outer tube 5, or the arc tube 6.

In this way, a lamp whose fuse has simply blown out can be easily reused by simply removing the cap 10 and replacing the fuse part.

The fuse used was 0.5 mm in diameter and 2 mm in length.
It is a constant line of 0 mm.

As described above, installing a fuse in a high-pressure discharge lamp is essential for preventing danger to humans and as a safety measure.

Furthermore, we have discovered that this measure is not perfect unless the fuse is attached to a part of the lead wire that leads to the eyelet side of the first cap.

Implementing this invention does not require any advanced technology, it is easy to implement, and it has the great advantage of completely preventing hidden unexpected accidents caused by misuse. 1. Effects obtained by implementing the present invention is considered to be extremely thick from the standpoint of emphasizing safety.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an example of a fixture attached to a ceiling or the like, and FIG. 2 is a circuit diagram of a main part of a lamp for explaining the present invention. In the figure, 5 is the lamp envelope tube, 6 is the arc tube, 8 is the stem, and 9
, 9' are lead wires, and 10 is a base, respectively.

Claims (1)

[Claims] 1. In high-pressure discharge lamps that require a separate ballast, one of the power supply lead wires that exits from the lamp envelope and exists in the cap and is connected to the eyelet side of the cap. A high-pressure discharge lamp characterized in that a fuse is provided in series with the section to cut off the power supply circuit by blowing at a current exceeding the rated current.