JP2001242434A - Liquid crystal projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the dust, etc., from infiltrating in a cabinet, maintaining cooling effect of optical components. SOLUTION: An air inflow hole 11 is opened on a cabinet 1 of a liquid crystal projector and a light source 2, a liquid crystal panel 7 irradiated by the light source 2 and an exhaust fan 3 to air-cool the light source 2 are equipped in the cabinet 1. The light source 2 is disposed on the flow passage of the air from the air inflow hole 11 to the exhaust fan 3, and projects the irradiation image of the liquid crystal panel 7 on a front screen. The air supply fan 4 is provided, opposite to the air inflow hole 11 on the cabinet 1 and the quantity of air supply of the air supply fan 4 is set larger than the exhaust volume of the exhaust fan 3 to maintain the inside of the cabinet 1 in a positive pressure state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal projector for projecting an image on a liquid crystal panel by irradiating it with strong light.

[0002]

2. Description of the Related Art FIG. 4 is a sectional side view of a conventional liquid crystal projector. This is a so-called single-panel type liquid crystal projector, which irradiates an image displayed on one liquid crystal panel (7) provided in a cabinet (1) with strong light from a light source (2), and projects a projection lens. In (6), the image is displayed on the front screen
(Not shown). The viewer sees the projected image from behind the cabinet (1). The projection lens (6) is a cabinet
It passes through a through hole (10) opened in front of (1). light source
(2) emits intense light and tends to become hot, so the light source (2)
Behind this, a through hole (10) of the cabinet (1) and an exhaust fan (3) for cooling are provided. Since the liquid crystal panel (7) is easily damaged by heat, an air inlet (11) and a filter (5) for removing dust are provided on the side of the liquid crystal panel (7). The air that has entered the cabinet (1) through the air inlet (11) cools the liquid crystal panel (7) and the light source (2) and is then discharged out of the cabinet (1) by the exhaust fan (3).

[0003]

In the conventional apparatus, since the air in the cabinet (1) is forcibly exhausted by the exhaust fan (3), the inside of the cabinet (1) is kept in a negative pressure state. is there. Filter for dust removal is located in the air inlet (11)
Although (5) is provided, there is a possibility that dust or the like outside the cabinet (1) may enter through the through hole (10) due to a negative pressure state. Further, as described later, the cabinet (1) is configured by combining a plurality of members, and there is a possibility that dust or the like may enter through gaps between the members. When the dust or the like adheres to the liquid crystal panel (7), the dust or the like appears on the screen as a shadow, giving a strange feeling to the viewer. In particular, in recent years, high resolution has been required, and even if a small amount of dust or the like adheres to the liquid crystal panel (7), it tends to appear as a shadow on the screen. An object of the present invention is to prevent dust and the like from entering a cabinet while maintaining a cooling effect of an optical component.

[0004]

Means for Solving the Problems Liquid Crystal Panel Cabinet
(1) An air supply fan (4) is provided on the upper surface so as to face the air inlet hole (11), and the air supply fan (4) is provided with an air supply amount larger than the exhaust amount of the exhaust fan (3). The inside of the cabinet (1) is maintained at a positive pressure.

[0005]

[Operation and Effect] By keeping the inside of the cabinet (1) in a positive pressure state, dust and the like floating outside the cabinet (1) do not enter the cabinet (1). Thereby, it is possible to prevent a shadow such as dust from appearing on the screen. Further, since air is supplied into the cabinet (1) by the air supply fan (4), the cooling effect of the light source (2) does not decrease.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an example of the present invention will be described in detail with reference to the drawings. FIG. 1 is a sectional plan view of the cabinet (1). Inside the cabinet (1), a liquid crystal panel (7), a light source (2) for irradiating the image of the liquid crystal panel (7) with intense light, and the light source (2) are cooled, Cabinet (1)
An exhaust fan (3) for discharging the air inside to the outside is provided. On the cabinet (1), an air inlet (11) is opened on the side of the liquid crystal panel (7), and an exhaust hole (16) is opened facing the exhaust fan (3). The liquid crystal panel (7) and the light source (2) are provided on an air flow path from the air inlet (11) to the exhaust fan (3). By disposing the liquid crystal panel (7) on the upstream side of the flow path from the air inlet (11) to the exhaust fan (3), the heat of the light source (2) hits the liquid crystal panel (7) by the flow of air. Is preventing. In the cabinet (1), a filter (5) for removing dust and an air supply fan (4) are provided inside the air inlet (11).

Air from the outside of the cabinet (1) passes through the filter (5) by the air supply fan (4) and enters the cabinet (1) through the air inlet (11). cabinet
The air flowing into (1) is the liquid crystal panel (7) and the light source (2)
After cooling, the cabinet is turned on by the exhaust fan (3).
It is discharged outside (1).

In the cabinet (1), in addition to the through hole (10) into which the projection lens (6) fits, several gaps (12) (12) (12) (12)
Is provided. As shown in FIG. 3, the cabinet (1) closes the front and rear openings of a frame (13) formed by bending a metal plate with closing plates (14) (14) formed of synthetic resin. The exhaust hole (16) and the light source are formed in one closing plate (14).
(2) There is a replacement window (15). The gap (12)
(12), (12) and (12) indicate gaps at the joint between the frame (13) and the closing plate (14). In order to prevent dust from entering the cabinet (1) through the gaps (12), (12), (12), (12) and the through hole (10), the following measures are taken.

Features of the present embodiment The air supply amount of the air supply fan (4) in FIG. 1 is provided to be larger than the exhaust amount of the exhaust fan (3). During operation of both fans (4) and (3), the amount of air sucked by the air supply fan (4) is larger than the amount of air exhausted by the exhaust fan (3). The inside of the cabinet (1) is kept at a higher pressure than the outside. As a result, even if dust or the like outside the cabinet (1) approaches the cabinet (1), the dust inside the cabinet (1) is pushed by the air in the cabinet (1) and does not enter the interior of the cabinet (1). Therefore, it is possible to prevent shadows on the screen due to dust adhering to the liquid crystal panel (7). In FIG. 1, a diffusion fan (30) is provided on the opposite side of the air supply fan (4) with the liquid crystal panel (7) interposed therebetween, and this diffuses air in the cabinet (1). Stir,
The temperature distribution in the cabinet (1) is made substantially uniform.

Further, as shown in FIG.
(1) Instead of installing an air supply fan (4) inside,
(11) may be provided with an air supply unit (8). It has a box (80) with an air supply fan (4) on the side,
An intake hole (81) and a filter (5) are provided opposite to (4). The air outside the box (80) enters the box (80) through the filter (5) through the intake hole (81) by the air supply fan (4). The air in the box (80) enters the cabinet (1) from the air inlet (11), cools the liquid crystal panel (7) and the light source (2), and cools the cabinet (1) from the exhaust fan (3). Released outside. A duct (40) may be provided from the air inlet (11) to the exhaust fan (3), as shown by the dashed line in FIG. In the above example, a single-panel type liquid crystal projector is shown, but a liquid crystal projector having three liquid crystal panels corresponding to the three primary colors of light, R, G, and B, may be used.

The description of the above embodiments is for the purpose of illustrating the present invention, and should not be construed as limiting the invention described in the appended claims or reducing the scope thereof. Further, the configuration of each part of the present invention is not limited to the above-described embodiment, and it is needless to say that various modifications can be made within the technical scope described in the claims.

[Brief description of the drawings]

FIG. 1 is a sectional plan view of a cabinet.

FIG. 2 is a sectional plan view of a cabinet in another embodiment.

FIG. 3 is an exploded perspective view of the cabinet.

FIG. 4 is a cross-sectional side view of a conventional liquid crystal projector.

[Explanation of symbols]

 (1) Cabinet (2) Light source (3) Exhaust fan (7) LCD panel (11) Air inlet

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Takao Matsumura 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. F-term (reference) 2H088 EA13 HA28 MA01 MA20 5C058 AA06 AB04 BA33 BA35 EA26 EA52

Claims (1)

[Claims] An air inlet (11) is opened in a cabinet (1), and a light source (2), a liquid crystal panel (7) illuminated by the light source (2), and a light source ( It has an exhaust fan (3) for air cooling 2), and the light source (2) has an air inlet.
In a liquid crystal projector which is arranged on an air flow path from (11) to an exhaust fan (3) and projects an irradiation image of a liquid crystal panel (7) on a front screen, an air inlet (11) is provided on a cabinet (1). ), An air supply fan (4) is provided, and the air supply fan (4) is provided with an air supply amount larger than the exhaust amount of the exhaust fan (3), and
(1) A liquid crystal projector characterized in that the inside thereof is maintained in a positive pressure state.