JPH10223023A - Light irradiating unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To cool a lamp, and prevent scattering of broken pieces when the lamp is broken, by forming a notch part by cutting off an opening part end part of a concave reflecting mirror in plural places, covering a front opening of the concave reflecting mirror to surround a discharge lamp or a front opening of a lighting fixture with a front face plate composed a light transmissive material, and covering the notch part and a ventilating window of the lighting fixture with a ventilating plate. SOLUTION: A front glass installing member 41 on which a glass plate 4 is installed is fixed to a front opening of a concave reflecting mirror 2, and a mesh member 5 as a ventilating plate through which broken pieces of a discharge lamp 1 cannot pass is installed in the front glass installing member 41, and covers a notch part 22 of the concave reflecting mirror 2. A cooling wind enters the concave reflecting mirror 2 from an air vent of a base sleeve 13, and flows out of the notch part 22 by cooling the discharge lamp 1. Since this unit is formed in such a structure, even if the discharge lamp 1 bursts, the broken pieces of the discharge lamp 1 do not scatter outside from the concave reflecting mirror 2, and damage of the inside of a projector, a wiring cord and a combustible member can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light irradiation unit used for a light source of a projection device.

[0002]

2. Description of the Related Art In recent years, an OHP (overhead projector) or a liquid crystal projector has been used as a presentation tool. In these projection devices,
As a light source lamp, a short arc type metal halide lamp with excellent luminous efficiency is often used, but this metal halide lamp is surrounded by a concave reflecting mirror, and furthermore, this is made of a heat-resistant resin or metal box type. The light irradiation unit incorporated in the lamp is built in the projection device.

[0003]

In a short arc type metal halide lamp used as a light source lamp, the pressure in an arc tube becomes as high as about 20 to 150 atm at the time of lighting. There is a risk that the arc tube will deteriorate and the lamp will explode. If the lamp explodes, fragments of quartz glass or translucent ceramics constituting the arc tube scatter in the projection device. At this time, since the scattered arc tube fragments are extremely high in temperature, the wiring cords and flammable members in the projection device may be damaged.

For this reason, it has been proposed to cover the front opening of the concave reflector with a glass plate to make the interior of the concave reflector a closed space and to arrange the lamp in this closed space as a measure against rupture of the lamp. (For example, JP-A-8-7841). However, recently, there has been a great demand for improving the screen illuminance, and the output of lamps has been increasing. Therefore,
There is a need to ventilate the cooling air for cooling the lamp inside the concave reflecting mirror, and this also cuts off the end of the opening of the concave reflecting mirror to form a notch in order to reduce the size of the equipment. May be used for business. However, in such a structure, when the lamp is broken, there is a problem that pieces of quartz glass are scattered from the cutout portion for ventilation.

Accordingly, an object of the present invention is to provide a light irradiation unit that can sufficiently cool a lamp and that does not cause fragments of an arc tube to scatter in a projection device even if the lamp explodes. .

[0006]

In order to achieve the above object, the invention of claim 1 relates to a light irradiating unit which does not use a box-shaped lamp, and has a plurality of end portions of an opening of a concave reflecting mirror. To form a notch, cover the front opening of the concave reflector with a front plate made of a translucent material, and cover the notch of the concave reflector with a ventilation plate through which fragments when the lamp is damaged cannot pass. cover.

Next, the inventions of claims 2 and 3 are:
The present invention relates to a light irradiating unit in which a concave reflecting mirror is mounted so as to be inscribed in a box-shaped lamp. A vent window is formed at a position corresponding to the notch portion of the lamp, and a front opening of the lamp is covered with a front plate made of a light-transmitting material, and the vent window is damaged. Cover with a ventilation plate through which debris cannot pass.

On the other hand, according to a third aspect of the present invention, the notch is formed by cutting off the end of the opening of the concave reflecting mirror at a plurality of places, and the arc-shaped corner of the front opening of the concave reflecting mirror and the square in the lamp are formed. Cover the substantially triangular corner defined by the corner of the lamp with a ventilation plate through which debris when the lamp is broken cannot pass, and place a front plate made of a translucent material in the front opening of the lamp, and attach it to the lamp. Form an exhaust part.

[0009]

Embodiments of the present invention will be specifically described below with reference to the drawings. 1 and 2 show an embodiment of the first aspect of the present invention. In FIG. 1, a discharge lamp 1 as a light source lamp of a light irradiation unit is, for example, a metal halide lamp consuming 250 W of power, and an arc tube is formed of quartz glass or translucent ceramic. A lamp base 12 is attached to one sealing portion 11 of the discharge lamp 1. The concave reflecting mirror 2 is made of borosilicate glass and has a central hole 21 in its neck.
Are formed. Then, the lamp base 12 of the discharge lamp 1 is inserted into the center hole 21 of the concave reflecting mirror 2 through the base sleeve 13 having a vent, and the discharge lamp 1 is fixed to the concave reflecting mirror 2 by the adhesive 14. The base sleeve 13 with the vent hole is a cylindrical body, and as shown in FIG. 2, two notches 13a of, for example, 90 ° are formed on the peripheral surface of the cylindrical body so as to face each other. Ventilation holes.

Here, the concave reflecting mirror 2 has its opening end cut off from all sides, and as shown in FIG. 2, the shape of the front opening of the concave reflecting mirror 2 is such that the corners are arc-shaped. It is almost square. Therefore, at the end of the opening of the concave reflecting mirror 2, for example, four notches 22 are formed as shown in FIG. In addition, only the two sides of the end of the opening of the concave reflecting mirror 2 may be cut off to form only two opposing notches 22.

A front glass mounting member 41 to which a glass plate 4 is mounted is fixed to the front opening of the concave reflecting mirror 2. That is, the front opening of the concave reflecting mirror 2 is covered with the glass plate 4 which is a front plate made of a translucent material. Also,
Four mesh members 5 are attached to the front glass attachment member 41 as ventilation plates through which fragments of the lamp cannot pass, and the mesh members 5 cover the cutout portions 22 of the concave reflecting mirror 2. The size of the mesh of the mesh member 5 is, for example, 0.4
It is about 1.6 mm and has sufficient air permeability, but even if the discharge lamp 1 ruptures, fragments of the discharge lamp 1 cannot pass. Note that the front glass mounting member 41 and the mesh member 5 may be integrally formed of a heat-resistant synthetic resin. Such a light irradiation unit is built in, for example, a liquid crystal projector, and light reflected by the concave reflecting mirror 2 irradiates the liquid crystal panel.

As described above, in the discharge lamp 1 surrounded by the concave reflecting mirror 2, the front opening of the concave reflecting mirror 2 is
And the notch 22 of the concave reflecting mirror 2 is covered with the mesh member 5, so that even if the discharge lamp 1 ruptures, fragments of the discharge lamp 1 scatter outside from the concave reflecting mirror 2. Nothing. Therefore, the wiring cord and the flammable member in the liquid crystal projector are not damaged. In the case of this embodiment,
The cooling air enters the concave reflecting mirror 2 through the vent hole of the base sleeve 13, cools the discharge lamp 1, and flows out of the notch 22. In this case, the vent hole portion of the base sleeve 13 may be covered with a mesh member. Conversely, cooling air may enter through the notch and flow out of the vent hole of the base sleeve 13. In the case of a discharge lamp that does not use the base sleeve 13 with the vent hole, that is, when the central hole 21 that is the connection portion between the discharge lamp 1 and the concave reflecting mirror 2 is closed, one of the notches 22 is The cooling air that has entered the inside of the reflector is the discharge lamp 1
Is cooled and exits from the other cutout 22.

Next, a second embodiment of the present invention will be described with reference to FIGS. In FIG. 3, the structures of the discharge lamp 1 and the concave reflecting mirror 2 are the same as those of the embodiment shown in FIG. 1, but the concave reflecting mirror 2 is attached in a state in which it is inscribed in the lamp 3 as shown in FIG. ing. The lamp 3 is formed in a box shape from a heat-resistant plastic such as PPS or an aluminum plate. Four substantially triangular corners C defined by an arc-shaped corner of the front opening of the concave reflecting mirror 2 and a quadrangular corner in the lamp 3 are formed, and each of the corners C is a partition plate. It is closed at 6. That is, the front part and the rear part of the lamp 3 are cut off by the concave reflecting mirror 2 and the partition plate 6 so that the fragments of the discharge lamp 1 do not scatter behind the lamp 3. The front opening of the lamp 3 is covered with a glass plate 4 which is a front plate made of a translucent material.
A ventilation window 31 is formed on each side of the lamp 3, and the ventilation window 3 is formed.
Numerals 1 are respectively connected to the notches 22 of the concave reflecting mirror 2, and a mesh member 5 is attached to the back side of the ventilation window 31. A power connector 7 is arranged behind the lamp 3.

When the lamp 3 is formed of a heat-resistant plastic such as PPS, the corner of the lamp 3 is formed into an arc shape in accordance with the shape of the front surface of the concave reflector 2, and the corner of the front opening of the concave reflector 2 and the lamp are formed. 3 can be brought into close contact with each other. In this case, a state in which the mesh member 5 is attached is shown in FIG.
Shown in

As described above, according to the second aspect of the present invention, the discharge lamp 1 surrounded by the concave reflecting mirror 2 has the front opening of the lamp 3 covered with the glass plate 4 and the partitioning plate 6 for the concave reflecting mirror 2. Since the inside and the rear of the lamp 3 are shut off and the ventilation window 31 connected to the notch 22 of the concave reflecting mirror 2 is covered with the mesh member 5, even if the discharge lamp 1 ruptures, the discharge The fragments of the lamp 1 do not scatter outside from the concave reflecting mirror 2. Also in this case, similarly to the embodiment of FIG.
The cooling air flows from the vent hole of the base sleeve 13 through the concave reflecting mirror 2.
And flows out from the notch 22. Or, conversely, the cooling air flows from the notch 22 to the inlet sleeve 1.
3 flows out of the vent. In this case, the cap sleeve 13
May be covered with a mesh member. When the base sleeve 13 with the ventilation hole is not used, the cooling air that has entered the concave reflecting mirror 2 from one ventilation window 31 and the notch 22 cools the discharge lamp 1 and the other notch 22 and the ventilation Get out of window 31.

FIGS. 6 and 7 show an embodiment of the third aspect of the present invention. In FIG. 6, a discharge lamp 1 and a concave reflecting mirror 2 are shown.
Is the same as that of the embodiment shown in FIG. Then, as shown in FIG. 7, the concave reflecting mirror 2 is attached in a state in which it is inscribed in the lamp 3, as in the embodiment of the second aspect of the present invention. The front opening of the lamp 3 is also covered with a glass plate 4 which is a front plate made of a translucent material, as in the embodiment of the second aspect of the present invention. A substantially triangular shape 4 defined by an arc-shaped corner of the front opening of the concave reflecting mirror 2 and a square corner in the lamp 3
The corner portions C are covered with the mesh member 5, and the fragments of the lamp cannot pass through. The exhaust 3 is formed in the lamp 3.

The cooling air enters the concave reflecting mirror 2 through the vent hole of the base sleeve 13 and flows out of the exhaust part 32 of the lamp 3 through the mesh member 5 at the corner C, as in the embodiment of FIG. . Alternatively, it is also possible to use the exhaust part 32 as an inlet for the cooling air and the vent hole of the base sleeve 13 as the outlet. In this case, the ventilation holes of the base sleeve 13 may be covered with a mesh member. It is sufficient that some of the corners C are covered with the mesh member 5, and the remaining corners C may be closed by the partition plates. When the base sleeve 13 with the ventilation hole is not used, one or a plurality of ventilation windows 31 are formed on the side surface of the lamp 3 as shown in FIG.
On the back side of the ventilation window 31, the mesh member 5 is attached.
Then, the cooling air enters through the ventilation window 31 and flows out of the exhaust part 32 of the lamp 3 through the mesh member 5 of the corner portion C.

The front opening of the lamp 3 is covered with a glass plate 4,
Since the corner portion C is covered with the mesh member 5 or the mesh member and the partition plate, and the ventilation window 31 is also covered with the mesh member 5,
Even if the discharge lamp 1 ruptures, fragments of the discharge lamp 1 do not scatter outside from the concave reflecting mirror 2. In the above embodiment, the mesh member is taken as a typical example of the ventilation plate through which the fragments cannot be passed when the lamp is ruptured.However, the present invention is not limited to this, and the cooling air passes and the lamp fragments do not pass. Anything should do.

[0019]

As described above, according to the present invention, the front opening of the concave reflecting mirror surrounding the discharge lamp or the front opening of the lamp is covered with the front plate made of a light-transmitting material, and the cooling air passage portion. Since the notch of the concave reflector and the ventilation window of the lamp were covered with a ventilation plate through which the debris from the lamp could not pass, the lamp could be cooled sufficiently, and even if the lamp burst, the debris could be lost. A light irradiation unit that does not scatter in the projection equipment can be provided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an embodiment of the present invention.

FIG. 2 is a rear view of the first embodiment of the present invention;

FIG. 3 is a sectional view of an embodiment of the invention according to claim 2;

FIG. 4 is a view of a cross section taken along line AA ′ of FIG. 3 viewed in a direction of an arrow.

FIG. 5 is a sectional view of another embodiment of the invention of claim 2;

FIG. 6 is a sectional view of an embodiment of the invention according to claim 3;

FIG. 7 is a view of a cross section taken along line BB ′ of FIG. 6 viewed in a direction of an arrow.

FIG. 8 is a sectional view of another embodiment of the third aspect of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Discharge lamp 11 Sealing part 12 Lamp base 13 Base sleeve 14 Adhesive 2 Concave reflector 21 Central hole of concave reflector 22 Notch of concave reflector 3 Lamp 31 Vent window 32 Exhaust part 4 Glass plate 5 Mesh member 6 Partition plate 7 Power connector C corner

Claims (3)

[Claims] 1. A discharge lamp is surrounded by a concave reflector.
In a light irradiation unit in which reflected light is emitted from a front opening of the concave reflecting mirror, an end of the opening of the concave reflecting mirror is cut off at a plurality of places to form a plurality of notches, and a front surface of the concave reflecting mirror is formed. A light irradiation unit, characterized in that the opening is covered with a front plate made of a translucent material, and the cutout portion is covered with a ventilation plate through which debris when the lamp is broken cannot pass. 2. A light irradiation unit in which a concave reflecting mirror surrounding a discharge lamp is disposed inscribed in a box-shaped lamp and reflected light is emitted from a front opening of the lamp, wherein the concave reflecting mirror has a plurality of opening ends. A cutout is formed at a location, and a vent window is formed in the lamp at a position corresponding to the notch, and the vent window cannot pass the fragments when the lamp is damaged. A light-transmitting unit, wherein the light-emitting unit is covered with a transparent ventilation plate, and a front plate made of a translucent material is disposed in a front opening of the lamp. 3. A light irradiation unit in which a concave reflecting mirror surrounding a discharge lamp is disposed inscribed in a box-shaped lamp, and reflected light is emitted from a front opening of the lamp, wherein the concave reflecting mirror has a plurality of opening ends. The notch was cut off at a location, and the lamp was broken at the substantially triangular corner defined by the arc-shaped corner of the front opening of the concave reflecting mirror and the square corner in the lamp. A light irradiating unit, wherein the light fragments are covered with a ventilation plate that cannot pass therethrough, a front plate made of a translucent material is disposed in a front opening of the lamp, and an exhaust portion is formed in the lamp.