JP2013145656A - Light source device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light source device structure that can prevent uncomfortable dissonance caused by vibrations of a feeding line when lighting up a lamp, in the light source device made of a short arc type discharge lamp lighted up with AC power supply and a concave surface reflecting mirror arranged to surround the discharge lamp, wherein an external lead of the discharge lamp projecting to a front opening side of the reflecting mirror is connected with the feeding line and the feeding line is introduced to the outside by penetrating a through-hole formed on the reflecting mirror.SOLUTION: The feeding line arranged in the reflecting mirror becomes a continuous wavy shape continuing by reversing a semicircular shape on the identical plane.

Description

  The present invention relates to a light source device including a high-pressure discharge lamp and a concave reflecting mirror, and more particularly to a light source device used in a projector device.

The short arc type high-pressure discharge lamp has a short tip distance between a pair of electrodes arranged opposite to each other in the arc tube, and is close to a point light source. Therefore, it can be used efficiently by combining it with an optical system such as a reflecting mirror. It can be used as a light source device for a projector device such as a projector.
For example, Japanese Patent Application Laid-Open No. 2009-117284 (Patent Document 1) is an example.

The structure is shown in FIG. 4, and the light source device includes a short arc type discharge lamp 10 in which a pair of electrodes are arranged to face each other, and a spheroid-shaped concave reflecting mirror 20 arranged so as to surround the short arc type discharge lamp 10. Become. The discharge lamp 10 includes a light emitting portion 11 and sealing portions 12 at both ends thereof, and a pair of electrodes 13 and 13 are disposed to face each other in the light emitting portion 11, and one sealing portion 12 is the concave reflecting mirror. Attached to the 20 neck portions 21 by an adhesive 23.
A power supply line 15 is connected to the external lead 14 protruding from the other sealing portion 12 on the front opening side of the reflecting mirror 20, and the power supply line 15 is reflected through a through hole 22 formed in the reflecting mirror 20. It is led out of the mirror and connected to an AC power source (not shown).

By the way, in such an AC lighting type light source device, there is a problem that unpleasant noise is generated during use, which is annoying for the projector user.
When the source of the unpleasant sound is located, a power supply line 15 (hereinafter also referred to as a lamp power supply line) stretched in the reflecting mirror 20 that supplies power to the discharge lamp 10 vibrates and generates sound. It has been found.

Further investigation on the sounding of the feeder line revealed that it was due to the following phenomenon.
As shown in FIG. 5, a light source device 1, a lighting power source 2, a lighting circuit 3, and the like are incorporated in a projector or a projector, and these are connected by a large number of wires.
Of these wirings, there is a wiring 4 that happens to be parallel to the power supply line 15 to the discharge lamp 10 in the light source device 1, and when a direct current flows through the wiring 4, It turned out that Lorentz force worked and this generated vibration and sound.

The Lorentz force will be briefly described with reference to FIG.
In the figure, an alternating current flows through the lamp feeder 15 and a direct current flows through the wiring 4 parallel thereto.
FIG 6 (A) as shown, the current I ₁ of the lamp power feed line 15, when the current I ₂ of the wiring 4 have the same orientation, become oriented in the same direction of the magnetic field, the magnetic field between the feed line 15 and the wiring 4 Are weakened to generate an attractive force F1.
Then, as shown in FIG. 6 (B), the direction of the current I ₁ flowing through the feed line 15 is reversed, the opposite direction to the current I ₂ of the orientation of the wire 4. At this time, the directions of the magnetic fields formed on the two lines are opposite to each other, and the magnetic field is strengthened between the feeder line 15 and the wiring 4 to generate a repulsive force F2 that repels each other.

That is, an attractive force and a repulsive force act alternately on the lamp power supply line 15 to which alternating current is supplied, and this causes the power supply line 15 to vibrate and cause a noise. Is.
There are a lot of wires in the device in which the light source lamp is installed, and if there is a wire that is parallel or nearly parallel to the power supply line, it will cause the noise of the power supply line due to the Lorentz force. It is.

In order to solve such a problem that noise is generated due to the vibration of the power supply line, Japanese Patent Application Laid-Open No. 2010-186656 (Patent Document 2) discloses that the power supply line is made of a paramagnetic or diamagnetic material. A structured technology has been proposed.
In this prior art, a molybdenum wire or a nickel wire (monel) wire containing 30% copper is used to reduce the electromagnetic force acting on the feed line and to reduce the vibration of the feed line to the lamp. A technique for preventing sound generation is disclosed.
However, such a technique has a problem that the material selection width of the power supply line is extremely limited and there is a restriction that a special material must be selected.

JP 2009-117284 A JP 2010-186656 A

  The problem to be solved by the present invention is a short arc discharge lamp that is turned on by alternating current and a concave reflecting mirror that is arranged so as to surround the discharge lamp, and a discharge lamp that projects to the front opening side of the reflecting mirror. In a light source device in which an external lead is connected to a power supply line, and the power supply line is led out through a through hole formed in the reflecting mirror, the power supply line vibrates and generates noise when the lamp is lit It is intended to provide a structure that prevents this.

  In order to solve the above-described problem, the light source device according to the present invention is configured such that the feeder line arranged in the concave reflecting mirror has a continuous waveform shape in which the semicircular shape is reversed in the same plane. Features.

  According to the light source device of the present invention, the feeding line connected to the external lead on the front end side of the discharge lamp does not generate a magnetic field even when AC is supplied, and is supplied with many other DCs in the device. Even if the wiring is parallel to the wiring, the Lorentz force does not work between the wiring and the power supply line does not vibrate, so that an unpleasant noise does not occur. It is what you play.

Sectional drawing of the light source device of this invention. Explanatory drawing of the feeder line of the light source device of this invention. Explanatory drawing of the relationship between the feeder line of this invention and the wiring in an apparatus. Sectional drawing of a prior art example. Explanatory drawing in which the conventional example was incorporated in the apparatus. The figure explaining the vibration of a feeder.

In FIG. 1, a short arc type discharge lamp 10 having a light emitting portion 11 and a sealing portion 12 is incorporated in a concave reflecting mirror 20. A power supply line 30 is connected to the external lead 14 protruding from the sealing portion 12 on the front opening side of the reflecting mirror 20 of the discharge lamp 10, and the power supply line 30 is a through-hole formed in the reflecting mirror 20. It is led out through the hole 22. A nickel wire is usually used as the power supply line 30, and this is a soft nickel wire, and the wire diameter Φ is selected from 0.5 to 2.0 mm according to the current to be applied.
The power supply line 30 may be a metal containing a plurality of conductive metals, or may be one in which an oxidation resistant metal is plated on the surface of the power supply line 30.
Thus, the feeder line 30 arranged in the reflecting mirror 20 has a continuous waveform shape in which the semicircular shape is reversed in the same virtual plane. This waveform shape preferably occupies 70% or more of the entire length of the feeder line 30 in the reflecting mirror 20. The locality radius is, for example, about 3 mm.

The details are shown in FIG. 2, and as shown in FIG. 2A, in the feeder line 30, the semicircular shapes 31 a, 31 b, 31 c, 31 d... And has a continuous wave shape. A case where the current I ₁ is flowing through the feeder line 30 will be described.
FIG. 2 (B) those showing an enlarged one 31a of the semicircular, when the current _{I 1} flows through the semi-shape feed line 31a, the feed line 31a, along the fed-wire 31a, Magnetic fields y ₁ , y ₂ , y ₃ ,... Are formed according to the respective locations.
These magnetic fields y ₁ , y ₂ , y ₃ ... Are combined and represented as a magnetic field Y ₁ passing through the half-shaped center P _{1. In} this case, the magnetic field is a downward magnetic field.

Similarly, in the adjacent semicircular shape 31b, an upward magnetic field Y2 passing through the center P2 is generated. Similarly, magnetic fields Y3 and Y4 passing through the centers P3 and P4 are formed in the next semicircular shapes 31c and 31d, respectively.
In this manner, magnetic fields opposite to each other are formed in the semicircular shape adjacent to the power supply line 30, so that they cancel each other, and consequently no magnetic field is formed in the power supply line 30.

For this reason, as shown in FIG. 3, even if a DC power supply is supplied to the wiring 4 in the vicinity of the power supply line 30 to which alternating current is supplied, a magnetic field is not formed in the power supply line 30, so the influence of the magnetic field of the wiring 4 There is no such thing as a Lorentz force. Therefore, the feeder line 30 does not vibrate and does not cause unpleasant noise.
The semicircular shape of the feeder line 30 does not need to be a semicircular shape in a strict sense, and any magnetic field may be used as long as it generates a magnetic field as a semicircular component and cancels it out. It doesn't have to be zero.
Moreover, the curvature radius does not need to be uniform, and those having several curvature radii may be combined, and at that time, the total magnetic field only needs to be zero or close to zero.

  As described above, in the light source device according to the present invention, the semicircular shape is reversed in the same plane with respect to the power supply line disposed in the reflecting mirror and connected to the external lead of the short arc discharge lamp that is AC-lit. By adopting a continuous waveform shape, no magnetic field is formed on this feeder line, Lorentz force does not act on other wires, and vibration occurs even when AC is supplied to the feeder line. Since it does not occur, unpleasant noise does not occur.

DESCRIPTION OF SYMBOLS 10 Discharge lamp 11 Light emission part 12 Sealing part 13 Electrode 14 External lead 20 Concave reflector 22 Through-hole 30 Feed line X Virtual plane Y Magnetic field

Claims (2)

A short arc type discharge lamp that is turned on by alternating current and a concave reflecting mirror that is arranged so as to surround the discharge lamp, and an external lead of the discharge lamp that projects to the front opening side of the reflecting mirror is connected to a power supply line. In the light source device in which the feeder line is led out through the through hole formed in the reflecting mirror,
The light source device, wherein the feeder line arranged in the reflecting mirror has a continuous wave shape with a semicircular shape reversed in the same plane. The light source device according to claim 1, wherein the power supply line is a nickel wire.

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