JP3500101B2 - LCD projector - Google Patents

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. 5 is a sectional side view of a conventional liquid crystal projector. This is a so-called single plate type liquid crystal projector, which irradiates an image displayed on a single liquid crystal panel (7) provided in a cabinet (1) with strong light from a light source (2) to project a projection lens. The image is displayed on the screen in front of (6).
Copy (not shown). The viewer looks at the projected image from behind the cabinet (1). Since the light source (2) emits strong light and tends to be hot, the cabinet (1) is behind the light source (2).
A through hole (10) and an intake fan (3) for cooling are provided.
The air in the cabinet (1) is through hole by the intake fan (3).
It is released from (10). Further, since the liquid crystal panel (7) is easily damaged by heat, a blower fan (30) for cooling is provided below the liquid crystal panel (7). Blower fan (30)
Sends air outside the cabinet (1) into the cabinet (1) through a filter (8) and a through hole (11) formed in the cabinet (1).

[0003]

In recent years, the light source (2) is required to have high brightness, and the light source (2) is likely to become hotter. Therefore, the intake fan (3) is required to flow a larger amount of air. And the blower fan (30) needs to be large. However, when the intake fan (3) and the blower fan (30) are increased in size, the operation noise becomes louder, and it is required to reduce the noise. As a countermeasure against this, the applicant has previously used a blower fan (30).
To the intake fan (3) is set to be long to prevent the smooth passage of the sound generated on the flow path (Japanese Patent Application No. 10-202631, which is an unpublished invention). Is). Applicants have conceived to further improve this configuration so that the air from the intake fan (3) flows out of the front of the cabinet (1). As mentioned above, the viewer is behind the cabinet (1), but when the air from the intake fan (3) touches the viewer, the viewer is uncomfortable. An object of the present invention is to prevent air from an intake fan from touching a viewer in a liquid crystal projector having a cooling mechanism against noise.

[0004]

In addition to the above-mentioned structure, a liquid crystal projector is a sound deadening box body in which an air passage chamber (43) through which exhaust gas from a cooling mechanism passes is formed outside a cabinet (1).
(4) is attached, and an opening (45) for exhausting air from the air passage chamber (43) is provided on the front surface of the sound deadening box body (4).

[0005]

[Operation and effect] Exhaust gas from the sound deadening box body (4) attached to the outside of the cabinet (1) passes through the air passage chamber (43) and is provided with an opening ( It is released from 45) to the outside. As a result, the exhaust air from the sound deadening box body (4) does not hit the viewer located behind the cabinet (1) and does not make the viewer feel uncomfortable.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION (First Embodiment) An example of the present invention will be described in detail below with reference to the drawings. In this example, the cabinet
A silencer box body (4) that reduces the noise of the intake fan (3) in (1)
Is provided. 1 is a sectional side view of a cabinet (1) and a sound deadening box body (4) attached to the outer surface of the cabinet (1), and FIG. 2 is a sectional plan view taken along the line AA of FIG. is there. FIG. 3 is a perspective view of the sound deadening box body (4). The structure in the cabinet (1) is the same as the conventional one, and in the cabinet (1), one liquid crystal panel (7) and a light source (2) for irradiating an image of the liquid crystal panel (7) with intense light are used. )When,
An air intake fan (3) that cools the light source (2) and discharges the air inside the cabinet (1) to the outside, and a blower fan that cools the liquid crystal panel (7) and takes in the air outside the cabinet (1).
It has (30).

As shown in FIG. 3, the silencing box body (4) comprises a vertical box (41) having an open front surface which is erected from the rear end of a horizontal box (40) having an open top surface. A sound deadening member (5) made of urethane, glass wool or the like is attached to the inner part of the (41). The horizontal box (40) has an opening (45) at the front, and the inside is divided into a plurality of rooms. The room is formed in the air inflow chamber (42) with a transparent window (46) on one side and around the air inflow chamber (42), and is formed as a labyrinth by a plurality of partition plates (44) (44). The air passage chamber (43) provided in the. The sound deadening member (5) may be provided on the side surfaces of the partition plates (44) (44) of the air passage chamber (43). Further, regarding the arrangement and size of the partition plate (44) and the flow path length of the air passage chamber (43), the frequency distribution of noise and the acoustics are set so as to reduce the noise level of the intake fan (3) as described later. It is determined in consideration of the engineering analysis method and the pressure loss of the exhaust air of the intake fan (3).

Air Flow Path As shown in FIG. 1, the cabinet (1) is placed on the sound deadening box body (4), and the rear end surface of the cabinet (1) closes the front opening of the vertical box (41). The cabinet (1) is detachably attached to the sound deadening box body (4) with screws or the like (not shown).
As shown by the alternate long and short dash line in FIG. 2, the blower fan (30) is installed on the air inflow chamber (42) and enters the air inflow chamber (42) from the outside of the cabinet (1) through the transparent window (10). The entered air enters the cabinet (1) through the through hole (11) of the cabinet (1) by the blower fan (30). The air that has entered the cabinet (1) is exhausted to the vertical box (41) through the through hole (10) by the intake fan (3) of FIG. 1 after cooling the liquid crystal panel (7) and the light source (2). To be done.

The air that has entered the vertical box (41) descends into the horizontal box (40) and passes through the air passage chamber (43). Since the air passage chamber (43) is formed in a labyrinth shape by the partition plates (44) and (44) as described above, the air passage is long. Intake fan
The sound of (3) propagates in the air, but because the air flow path is long,
The sound is gradually attenuated, and the sound level is reduced. The air flowing through the air passage chamber (43) is discharged to the outside of the sound deadening box body (4) through the opening (45). Since the viewer who is looking at the irradiation image of the cabinet (1) is often located behind the cabinet (1), the air cooled in the cabinet (1) does not touch the viewer, and Don't feel uncomfortable with. The applicant measured the noise level by mounting the sound deadening box body (4) on the cabinet (1) and found that the noise level was 3 dB lower than that when the sound deadening box body (4) was not mounted. Horizontal box (4
When the sound deadening member (5) was attached to the partition plates (44) (44) and the vertical box (41) of 0) and the noise level was measured in the same manner, it was compared with the case where the sound deadening box body (4) was not attached. And noise level is 7 dB
It turned out to be lowered.

(Second Embodiment) FIG. 4 is a sectional plan view of another silencing box body (4) and cabinet (1). The sound-deadening box body (4) is provided with air passage chambers (43) (43) on both sides of the inner surface, and a gap (47) is provided between the rear end surface on which the sound deadening member (5) is attached and the rear end portion of the cabinet (1). And covers all surfaces other than the front surface of the cabinet (1). Exhaust gas from the cabinet (1) flows from the intake fan (3) into the gap (47), passes through the air passage chambers (43) (43), and exits through the front openings (45) (45) of the sound deadening box (4). Is discharged.
Similarly to the above, the sound level is mitigated because the air passage through which the sound of the intake fan (3) is transmitted is long.

The silencing box body (4) is detachably attached to the cabinet (1) because the cabinet (1) may be used with the silencing box body (4) removed. For example, although the cabinet (1) is generally placed on a desk surface, the cabinet (1) may be used upside down and hung from the ceiling. In this case, the air flowing in the cabinet (1) does not come into contact with the viewer on the ground, and the noise of the intake fan (3) is hard to reach the viewer.
Remove cabinet (4) and use cabinet (1).

The above description of the embodiments is for explaining the present invention and should not be construed as limiting the invention described in the claims or reducing the scope. The configuration of each part of the present invention is not limited to the above-mentioned embodiment, and it goes without saying that various modifications can be made within the technical scope described in the claims.

[Brief description of drawings]

FIG. 1 is a cross-sectional side view of a cabinet and a sound deadening box attached to an outer surface of the cabinet.

FIG. 2 is a cross-sectional plan view taken along the line AA of FIG.

FIG. 3 is a perspective view of a sound deadening box body.

FIG. 4 is a cross-sectional plan view of another silencing box body and cabinet.

FIG. 5 is a sectional side view of a conventional liquid crystal projector.

[Explanation of symbols]

(1) Cabinet (2) Light source (7) LCD panel

─────────────────────────────────────────────────── ─── Continuation of front page (72) Hideki Matsubara 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Denki Co., Ltd. (72) Inventor Susumu Takehara 2-5-5 Keihanhondori, Moriguchi-shi, Osaka No. 5 within Sanyo Electric Co., Ltd. (56) Reference JP 2001-68882 (JP, A) JP 2001-83637 (JP, A) International publication 00/73850 (WO, A1) (58) Fields investigated (Int .Cl. ⁷ , DB name) G03B 21/00-21/30

Claims (3)

(57) [Claims] 1. A light source (2) in a cabinet (1),
A liquid crystal projector that includes a liquid crystal panel (7) illuminated by a light source (2), a projection lens (6), and a cooling mechanism that cools the light source (2) by air, and displays an illuminated image of the liquid crystal panel (7) on a front screen. At the outside of the cabinet (1), a sound deadening box body (4) having an air passage chamber (43) through which exhaust air from a cooling mechanism passes is attached, and the sound deadening box body (4) is a cabinet. Detachable on the outside of (1)
It is freely mounted and has an air passage chamber ( 43 ) on its front surface.
A liquid crystal projector characterized by being provided with an opening ( 45 ) for exhausting air from. 2. A light source (2) in a cabinet (1),
A liquid crystal projector that includes a liquid crystal panel (7) illuminated by a light source (2), a projection lens (6), and a cooling mechanism that cools the light source (2) by air, and displays an illuminated image of the liquid crystal panel (7) on a front screen. At the outside of the cabinet (1), a sound deadening box body (4) forming an air passage chamber (43) through which exhaust gas from the cooling mechanism passes is attached, and the sound deadening box body (4) is It is composed of an air inflow chamber (42) having a transparent window (46) on its side and an air passage chamber (43) formed around the air inflow chamber (42) and having a plurality of partition plates (44). A liquid crystal projector characterized in that 3. The liquid crystal projector according to claim 1, wherein the cooling mechanism is a fan that discharges the air in the cabinet to the air passage chamber.