JP2007206604A - Projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projector capable of attaining the noise reduction. <P>SOLUTION: The projector 1 includes: exhaust ports 21 and 22 formed in an outer housing 2; a ventilation housing 51 provided in the outer housing 2, including a first opening 52 communicating with the inside of the outer housing 2, and second and third openings 53 and 54 communicating with the outside of the outer housing 2 through the exhaust ports 21 and 22; a first axial fan 55 provided in the first opening 52 so as to ventilate between the inside of the outer casing 2 and the inside of the ventilation housing 51; and second and third axial fans 56 and 57 provided in the second and third openings 53 and 54, respectively so as to ventilate between the outside of the outer housing 2 and the inside of the ventilation housing 51. The first axial fan 55 is always driven, the second and third axial fans 56 and 57 are driven as necessary. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a projector.

2. Description of the Related Art Conventionally, there has been known a projector that modulates a light beam emitted from a light source lamp with a light modulation device according to image information to form an optical image, and enlarges and projects the optical image.
The projector includes an exhaust unit that discharges air heated by heat generated by the light source or the light modulation device to the outside of the exterior casing of the projector. Furthermore, the discharge unit includes a fan for blowing air.
If the fan of the blower unit is stopped while the projector is in use, the inside of the discharge unit becomes lower than the external pressure, and air may flow back from the outside of the exterior housing into the discharge unit. For this reason, during use of the projector, the fan is always driven in the discharge section.

In such projectors, the maximum amount of heat generated in the exterior housing has increased in recent years as the brightness of light source lamps has increased. For this reason, in order to achieve an exhaust amount corresponding to the maximum heat generation amount, a projector (for example, see Patent Document 1) in which a plurality of fans are provided in one discharge unit, or a large fan is provided in the exhaust unit. Projectors and the like have been devised.
In the projector described in Patent Document 1, first, air warmed in the exterior casing is collected in the housing portion. The housing is formed with two openings communicating with the outside on the exterior housing side, and an exhaust fan is provided in each of the openings. The air collected in the housing part is exhausted out of the exterior casing through the two openings by the exhaust fan.

JP 2000-10191 A

  However, the projector described in Patent Document 1 has a problem that noise is always high because a plurality of exhaust fans are driven even when the amount of heat generated in the exterior housing is small. Also, a projector having a large fan has a problem that noise is increased even in a state where the amount of heat generation is small because the fan is large.

  An object of the present invention is to provide a projector that can realize low noise.

  In order to achieve the above object, a projector according to the present invention includes a light source device, a light modulation device that modulates a light beam emitted from the light source device according to image information, and forms an optical image, and the light modulation device. A projection optical device for enlarging and projecting the optical image formed in the above, and an exterior housing containing each of the devices, wherein the exterior housing opening formed in the exterior housing, and the exterior housing A ventilation housing provided in the body and having an internal opening that communicates with the interior of the exterior housing, and an external opening that communicates with the exterior of the exterior housing via the exterior housing opening, and the interior opening. Provided inside the front exterior casing and between the ventilation casings during operation, and an internal fan that is provided in the external opening and outside the exterior casing and inside the ventilation casing as needed during operation. Air between Characterized in that it comprises an external side fan that.

According to the present invention, the external fan is driven as necessary. For example, the external fan is stopped when the amount of heat generated in the exterior casing is small and the amount of ventilation inside and outside the exterior casing may be small (normal state). I can keep it. In this case, since noise only from the internal fan is generated, noise generated in the projector in the normal state can be suppressed.
And since the internal side fan is always driven, the pressure in a ventilation housing | casing is not reduced from the external pressure outside an exterior housing | casing. Therefore, for example, when it is desired to exhaust the warmed air in the exterior casing to the outside of the exterior casing via the ventilation casing, the air is prevented from flowing back from the exterior casing to the ventilation casing and the exterior casing. be able to.
Furthermore, since the constantly driven internal fan is provided inside the exterior casing surface through the ventilation casing, the driving sound of the internal fan felt by the projector user is derived from the driving sound of the external fan. small. Therefore, noise generated in the projector in the normal state can be suppressed.

In this invention, it is preferable that the said internal side fan and the said external side fan are axial flow fans, and the ventilation direction of the said internal side fan and the ventilation direction of the said external side fan are not located on a straight line mutually.
According to the present invention, since the air blowing directions of the internal fan and the external fan are not aligned with each other, the light in the external housing passes through the gap between the internal fan and the external fan. It is possible to prevent leakage outside the body.

In the present invention, it is preferable that a plurality of the external openings are formed, and the external fans are respectively provided in the plurality of external openings.
According to the present invention, since a plurality of external openings and external fans are provided, the amount of ventilation between the exterior casing and the ventilation casing can be increased.
Furthermore, when driving the external fan, it is possible to select and drive from a plurality of external fans. Therefore, for example, it is possible to perform fine ventilation adjustment, such as increasing or decreasing the ventilation amount between the outside of the exterior casing and the inside of the ventilation casing in stages, or changing the air volume according to the ventilation direction.

In the present invention, it is preferable that the air blowing directions of at least two external fans among the plurality of external fans are not located on a straight line.
According to the present invention, since the blowing directions of at least two external fans are not aligned with each other, the drive state of the external fans can be adjusted so that the space between the exterior casing and the ventilation casing is adjusted. Ventilation direction of can be changed. For example, when the air in the ventilation casing is exhausted to the outside of the exterior casing by the external fan, it is possible to prevent the exhaust air from hitting the projector user or the viewer by adjusting the exhaust direction.

In the present invention, the internal fan has a discharge port disposed opposite the internal opening, and blows air in the exterior housing into the ventilation housing, and the external fan has a discharge port on the external side. It is preferable to face the opening and to blow the air in the ventilation casing to the outside of the exterior casing.
According to the present invention, air heated by heat generated by a light source device, a light modulation device, or the like can be efficiently exhausted outside the exterior housing. Therefore, it is possible to suppress an abnormal temperature rise in the exterior housing and prevent the projector from being broken.

  In the present invention, a temperature sensor provided in the exterior casing, a temperature acquisition unit that acquires the temperature in the exterior casing detected by the temperature sensor, and the interior of the exterior casing acquired by the temperature acquisition unit A temperature determination unit that determines whether or not the temperature is equal to or higher than a predetermined temperature; and a fan control that drives the external fan when the temperature determination unit determines that the temperature in the outer casing is equal to or higher than a predetermined temperature. It is preferable to provide a part.

According to the present invention, the external fan is driven when the internal temperature in the exterior casing is equal to or higher than a predetermined value. That is, when the internal temperature is less than a predetermined value, that is, when the amount of heat generated in the exterior casing is small, the external fan is not driven and only the internal fan is driven. Therefore, since only the noise due to the driving of the internal fan is generated, the noise generated in the projector in the normal state can be suppressed.
And if the internal temperature in an exterior housing becomes a predetermined value or more, by driving an external fan, the amount of ventilation inside and outside the exterior housing via the ventilation housing can be increased. Thus, by increasing the air flow rate, each device in the exterior casing can be cooled and the internal temperature can be lowered.

An embodiment of the present invention will be described with reference to FIGS.
[Configuration of Projector 1]
FIG. 1 is a diagram schematically showing a schematic configuration of the projector 1.
The projector 1 modulates a light beam emitted from a light source according to image information to form an optical image, and enlarges and projects the formed optical image on a screen (not shown). As shown in FIG. 1, the projector 1 includes an exterior casing 2, a projection lens 3 as a projection optical device, an optical unit 4, a ventilation unit 5, and the like.
Although not shown in FIG. 1, a power supply unit that supplies power to each component in the projector 1 in a space other than the projection lens 3, the optical unit 4, and the ventilation unit 5 in the exterior housing 2, In addition, a control device 6 that controls the entire projector 1 is arranged.

As shown in FIG. 1, the exterior housing 2 is formed in a substantially rectangular parallelepiped shape that accommodates and arranges the components 3 to 5 inside.
The exterior housing 2 is formed with an air inlet (not shown) for taking in cooling air outside the exterior housing 2 to the side of the projection lens 3 and below the liquid crystal panel 441. Two exhaust ports 21 and 22 for exhausting the air in the exterior housing 2 are formed at the corners opposite to the lens 3. The exhaust ports 21 and 22 correspond to the exterior casing opening of the present invention.

  Further, an operation panel (not shown) having a plurality of operation buttons is provided on the upper surface of the exterior housing 2. The operation panel has a power-on signal for turning on the projector 1, a power-off signal for shutting off the power, and an exhaust for changing the exhaust direction from the exhaust port in response to an input operation of the operation button. Various operation signals such as a direction change signal are output to the control device 6 described later.

The optical unit 4 is a unit that optically processes the light beam emitted from the light source device 411 (FIG. 1) under the control of the control device 6 to form an optical image corresponding to the image information. As shown in FIG. 1, the optical unit 4 has a substantially L shape in plan view extending along the back surface of the exterior housing 2 and extending along the side surface of the exterior housing 2. The detailed configuration of the optical unit 4 will be described later.
The projection lens 3 enlarges and projects the optical image formed by the optical unit 4 on the screen. The projection lens 3 is configured as a combined lens in which a plurality of lenses are housed in a cylindrical lens barrel.

[Detailed Configuration of Optical Unit 4]
As shown in FIG. 1, the optical unit 4 includes an illumination optical device 41, a color separation optical device 42, a relay optical device 43, an optical device 44, and these devices 41 to 44 that are housed and arranged therein, and a projection. And an optical component housing 45 for supporting and fixing the lens 3 at a predetermined position.
The illumination optical device 41 is an optical system for substantially uniformly illuminating an image forming area of a liquid crystal panel, which will be described later, constituting the optical device 44. As shown in FIG. 1, the illumination optical device 41 includes a light source device 411, a first lens array 412, a second lens array 413 as a condensing device, a polarization conversion element 414, and a superimposing device as a condensing device. A lens 415.

  As shown in FIG. 1, the light source device 411 includes a light source lamp 416 that emits a radial light beam, a reflector 417 that reflects the emitted light emitted from the light source lamp 416 and converges it at a predetermined position, and the reflector 417 converges the light. And a collimating concave lens 418 for collimating the luminous flux with respect to the optical axis A. As the light source lamp 416, a halogen lamp, a metal halide lamp, or a high-pressure mercury lamp is frequently used. Further, the reflector 417 is composed of an ellipsoidal reflector having a spheroidal surface, but may be composed of a parabolic reflector having a rotational paraboloid. In this case, the collimating concave lens 418 is omitted.

The first lens array 412 has a configuration in which small lenses having a substantially rectangular outline when viewed from the optical axis A direction are arranged in a matrix. Each small lens splits the light beam emitted from the light source device 411 into a plurality of partial light beams.
The second lens array 413 has substantially the same configuration as the first lens array 412, and has a configuration in which small lenses are arranged in a matrix. The second lens array 413, together with the superimposing lens 415, has a function of forming an image of each small lens of the first lens array 412 on an image forming area of a liquid crystal panel described later of the optical device 44.

The polarization conversion element 414 is disposed between the second lens array 413 and the superimposing lens 415, and converts light from the second lens array 413 into one type of polarized light.
Specifically, each partial light converted into one type of polarized light by the polarization conversion element 414 is finally substantially superimposed on an image forming area of a liquid crystal panel (to be described later) of the optical device 44 by the superimposing lens 415. In a projector using a liquid crystal panel of a type that modulates polarized light, only one type of polarized light can be used, and therefore approximately half of the light from the light source device 411 that emits randomly polarized light cannot be used. For this reason, by using the polarization conversion element 414, the light emitted from the light source device 411 is converted into substantially one type of polarized light, and the light use efficiency in the optical device 44 is increased.

As shown in FIG. 1, the color separation optical device 42 includes two dichroic mirrors 421 and 422 and a reflection mirror 423, and a plurality of partial light beams emitted from the illumination optical device 41 by the dichroic mirrors 421 and 422. It has a function of separating into three color lights of red, green and blue.
The relay optical device 43 includes an incident side lens 431, a relay lens 433, and reflection mirrors 432 and 434, and has a function of guiding the color light separated by the color separation optical device 42 to a liquid crystal panel for red light.

  At this time, the dichroic mirror 421 of the color separation optical device 42 transmits the red light component and the green light component of the light beam emitted from the illumination optical device 41 and reflects the blue light component. The blue light reflected by the dichroic mirror 421 is reflected by the reflection mirror 423 and passes through the field lens 419 to reach the liquid crystal panel for blue light. The field lens 419 converts each partial light beam emitted from the second lens array 413 into a light beam parallel to the central axis (principal ray). The same applies to the field lens 419 provided on the light incident side of the other liquid crystal panels for green light and red light.

  Of the red light and green light transmitted through the dichroic mirror 421, the green light is reflected by the dichroic mirror 422, passes through the field lens 419, and reaches the liquid crystal panel for green light. On the other hand, the red light passes through the dichroic mirror 422, passes through the relay optical device 43, and further passes through the field lens 419 to reach the liquid crystal panel for red light. Note that the relay optical device 43 is used for red light because the optical path length of the red light is longer than the optical path lengths of the other color lights, thereby preventing a decrease in light use efficiency due to light diffusion or the like. It is to do. That is, this is to transmit the partial light beam incident on the incident side lens 431 to the field lens 419 as it is. The relay optical device 43 is configured to pass red light out of the three color lights, but is not limited thereto, and may be configured to pass blue light, for example.

The optical device 44 includes three liquid crystal panels 441 as light modulation devices (441 R for a red light liquid crystal panel, 441 G for a green light liquid crystal panel, and 441 B for a blue light liquid crystal panel) and three incident light beams. A side polarizing plate 442, three exit side polarizing plates 443, and a cross dichroic prism 444 are provided.
As shown in FIG. 1, the three incident-side polarizing plates 442 are respectively arranged in the rear stage of the optical path of each field lens 419. These incident-side polarizing plates 442 receive the respective color lights whose polarization directions are aligned in substantially one direction by the polarization conversion element 414, and of the incident light beams, the polarization orientations of the light beams aligned by the polarization conversion element 414 are substantially the same. It transmits only polarized light in the same direction and absorbs other light beams. Although not shown in the drawing, these incident side polarizing plates 442 have a configuration in which a polarizing film is pasted on a translucent substrate such as sapphire or quartz.

As shown in FIG. 1, the three liquid crystal panels 441 are respectively arranged on the rear side of the optical path of each incident side polarizing plate 442. Although not shown, these liquid crystal panels 441 have a configuration in which a liquid crystal, which is an electro-optical material, is hermetically sealed between a pair of transparent glass substrates, and in accordance with a driving signal output from the control device, The alignment state of the liquid crystal at the pixel position is controlled, and the polarization direction of the polarized light beam emitted from each incident-side polarizing plate 442 is modulated.
As shown in FIG. 1, the three exit-side polarizing plates 443 are respectively arranged in the rear stage of the optical path of each liquid crystal panel 441. These exit-side polarizing plates 443 have substantially the same configuration as the incident-side polarizing plate 442, and although not shown, have a configuration in which a polarizing film is attached to a light-transmitting substrate. The polarizing film constituting the exit side polarizing plate 443 is disposed so that the transmission axis that transmits the light beam is substantially orthogonal to the transmission axis that transmits the light beam at the incident side polarizing plate 442.

  The cross dichroic prism 444 is an optical element that is arranged in the downstream of the light path of the exit side polarizing plate 443 and forms a color image by combining optical images modulated for each color light emitted from the exit side polarizing plates 443. The cross dichroic prism 444 has a square shape in plan view in which four right angle prisms are bonded together, and two dielectric multilayer films are formed on the interface where the right angle prisms are bonded together. These dielectric multilayer films reflect each color light emitted from the liquid crystal panels 441R and 441B through the respective emission side polarizing plates 443, and pass through the color light emitted from the liquid crystal panel 441G and the emission side polarizing plates 443. In this manner, the color lights modulated by the liquid crystal panels 441 are combined to form a color image.

  The optical component storage housing 45 includes a light source storage chamber 451 in which the light source device 411 is stored, an optical component storage chamber 452 formed in a container shape in which other optical components other than the light source device 411 are stored, and the optical component. A projection lens installation portion (not shown) is provided on the outer surface of the storage chamber 452 and on which the projection lens 3 is installed.

The light source storage chamber 451 is formed in a substantially box shape having openings 4511 and 4512 on the optical component storage chamber 452 side and on the end surface opposite to the optical component storage chamber 452, respectively. Air can flow into and out of the light source storage chamber 451 through the openings 4511 and 4512.
A temperature sensor 7 is attached to the inner wall of the light source storage chamber 451. The temperature sensor 7 detects the resistance value of the thermistor having temperature characteristics, and outputs the detected resistance value data to the control device 6.
Openings (not shown) are formed at positions corresponding to the three liquid crystal panels 441R, 441G, and 441B of the optical device 44 and positions corresponding to the polarization conversion element 414 on the bottom surface portion of the optical component storage chamber 452. Yes.

  Cooling air taken in from each air inlet of the exterior housing 2 is sent to the light source storage chamber 451 and the optical component storage chamber 452 from the openings 4511 and 4512, and after cooling the light source lamp 416, the liquid crystal panel 441, and the like, It exhausts from the exhaust ports 21 and 22 through the ventilation unit 5 mentioned later.

[Configuration of Ventilation Unit 5]
The cooling unit will be described with reference to FIGS. FIG. 2 is a perspective view of the ventilation unit 5 as seen from the center on the back side of the projector 1. Here, in FIGS. 1 and 2, the projection direction of the projection lens 3 is the + Y-axis direction, and the emission direction of the light beam that is orthogonal to the Y-axis direction and is emitted from the light source device 411 is the + X-axis direction.
As shown in FIG. 1, the ventilation unit 5 is disposed along the Y axis direction on the −X axis direction side of the light source device 411 in the exterior housing 2. As shown in FIGS. 1 and 2, the ventilation unit 5 is arranged to face the ventilation casing 51 having the first opening 52, the second opening 53, and the third opening 54, and the openings 52, 53, 54, respectively. A first axial fan 55, a second axial fan 56, and a third axial fan 57 are provided.

As shown in FIGS. 1 and 2, the ventilation casing 51 has a substantially rectangular parallelepiped shape elongated in the Y-axis direction, and the + Y-axis direction end portions are oriented so that both side surfaces in the X-axis direction approach each other. It is inclined to form an acute angle portion. Here, the partition wall 511 on the + X-axis direction side of the ventilation casing 51 is the inner partition wall 511A, the partition wall 511 on the −X-axis direction side is the outer partition wall 511B, and the −X-axis side surface of the inclined + Y-axis side end is inclined outside. The partition wall is 511C.
The first opening 52 corresponds to the inner side opening of the present invention, and is formed at the end portion in the −Y-axis direction of the inner partition 511A. In other words, the first opening 52 faces the light source device 411 as shown in FIG.
The second opening 53 is formed in the inclined outer partition 511 </ b> C and faces the exhaust port 21 of the exterior housing 2. The third opening 54 is formed at the + Y-axis direction end of the outer partition 511 </ b> B and faces the exhaust port 22 of the exterior housing 2. The second opening 53 and the exhaust port 21, the third opening 54 and the exhaust port 22 constitute the external side opening of the present invention.

  The first axial fan 55 is attached to the partition wall 511 with the discharge port facing the first opening 52 and the suction port facing the opening 4512 of the light source storage chamber 451. In other words, the first axial fan 55 blows the air in the light source storage chamber 45 into the ventilation casing 51 through the opening 4512 and the first opening 52. The blowing direction of the first axial fan 55 is the −X axis direction. The first axial fan 55 corresponds to the internal fan of the present invention.

  The second axial fan 56 is attached to the partition wall 511 with the discharge port facing the second opening 53. That is, the second axial fan 56 blows the air in the ventilation casing 51 out of the exterior casing 2 through the second opening 53 and the exhaust port 21. The blowing direction of the second axial fan 56 is a combined direction of the −X axis direction and the + Y axis direction. The second axial fan 56 corresponds to the external fan of the present invention.

The third axial fan 57 is attached to the partition wall 511 with the discharge port facing the third opening 54. That is, the third axial fan 57 blows the air in the ventilation casing 51 to the outside of the exterior casing 2 through the third opening 54 and the exhaust port 22, similarly to the second axial fan 56. . The third axial fan 57 corresponds to the external fan of the present invention.
The blowing direction of the third axial fan 57 is the −X-axis direction like the first axial fan 55, but the plane when the ventilation unit 5 is viewed from the −X-axis direction side with reference to FIGS. 1 and 2. In view, the blowing shaft of the first axial fan 55 and the blowing shaft of the third axial fan 57 are shifted in the Y-axis direction and are not located on the same straight line.
Each axial fan 55, 56, 57 is driven under the control of the control device 6.

[Configuration of Control Device 6]
FIG. 3 is a block diagram for explaining a functional configuration related to the cooling process of the projector 1 by the ventilation unit 5 among the functional configurations of the control device 6.
The control device 6 includes an input signal acquisition unit 61 that acquires various operation signals output from the operation panel 23 of the exterior housing 2, a ventilation control unit 62, and a memory 63.
Among these, the memory 63 stores a program processed by the control device 6 and various data. For example, the memory 63 stores a ventilation unit control program for causing the projector 1 to perform a cooling process, a reference temperature T ₀ described later, and the like.

The ventilation control unit 62 controls the driving of the axial fans 55, 56, and 57 in accordance with the temperature in the light source storage chamber 451 and the input operation of the operation panel 23, and exhausts the air in the ventilation casing 51. Let The ventilation control unit 62 includes a temperature acquisition unit 621, a temperature determination unit 622, a first fan control unit 623, a second fan control unit 624, and a third fan control unit 625.
The temperature acquisition unit 621 monitors resistance value data output from the temperature sensor 7 attached in the light source storage chamber 451, analyzes the resistance value data, and acquires the internal temperature T of the light source storage chamber 451. .
The temperature determination unit 622 compares the internal temperature T acquired by the temperature acquisition unit 621 with the reference temperature T ₀ in the memory 63 and determines whether the internal temperature T is equal to or higher than the reference temperature T ₀ .

The first fan control unit 623 controls the driving of the first axial fan 55. Specifically, the first fan control unit 623 starts and rotates the first axial fan 55 according to various input signals acquired by the input signal acquisition unit 61 and the determination result of the temperature determination unit 622. Adjust the number and stop rotation.
Similarly, the second fan control unit 624 and the third fan control unit 625 also control the driving of the second axial fan 56 and the third axial fan 57, respectively.

[Operation of the control device 6]
The operation of the control device 6 will be described with reference to FIG.
The control device 6 controls the driving of the ventilation unit 5 and cools the projector 1 in accordance with the internal temperature T of the light source storage chamber 451 and the input operation of the operation panel 23.
FIG. 4 is a flowchart for explaining the cooling process by the control device 6.
As shown in FIG. 4, the input signal acquisition unit 61 of the control device 6 monitors the input signal input to the control device 6 and determines whether or not the power-on instruction signal output from the operation panel 23 is input. It is determined (S1). When the power-on instruction signal is not input, the input signal acquisition unit 61 continues to monitor the input signal.

On the other hand, when the power-on instruction signal is input, the first fan control unit 623 constituting the ventilation control unit 62 drives the first axial fan 55 (S2).
The temperature acquisition unit 621 analyzes the resistance value data output from the temperature sensor 7 and acquires the internal temperature T in the light source storage chamber 451 (S3).
The temperature determination unit 622 monitors the internal temperature T acquired by the temperature acquisition unit 621 and determines whether the internal temperature T is equal to or higher than the reference temperature T ₀ (S4).

When the internal temperature T is equal to or higher than the reference temperature T ₀ , the second fan control unit 624 determines whether or not the second axial fan 56 is being driven (S5). When the second axial fan 56 is not driven, the second fan control unit 624 drives the second axial fan 56 (S6). On the other hand, when the second axial fan 56 is driven, the input signal acquisition unit 61 proceeds to step S9 and monitors the input signal input to the control device 6.
On the other hand, when the internal temperature T is lower than the reference temperature T ₀ , the second fan control unit 624 determines whether or not the second axial fan 56 is driven (S7). When the second axial fan 56 is being driven, the second fan controller 624 stops the second axial fan 56 (S8). On the other hand, when the second axial fan 56 is not driven, the input signal acquisition unit 61 proceeds to step S <b> 9 and monitors an input signal input to the control device 6.

In process S <b> 9, the input signal acquisition unit 61 determines whether or not an exhaust direction change signal output from the operation panel 23 has been input.
When the exhaust direction change signal is input, the third fan control unit 625 determines whether or not the third axial fan 57 is driven (S10). When the third axial fan 57 is not driven, the third fan control unit 625 drives the third axial fan 57 (S11). Then, the input signal acquisition unit 61 proceeds to the process S13 and monitors the input signal input to the control device 6. On the other hand, when the third axial fan 57 is driven, the third fan control unit 625 stops the third axial fan 57 (S12). Then, the input signal acquisition unit 61 proceeds to the process S13 and monitors the input signal input to the control device 6.
On the other hand, when the exhaust direction change signal is not input, the input signal acquisition unit 61 proceeds to step S13 and monitors the input signal input to the control device 6.

  In process S13, the input signal acquisition unit 61 determines whether or not a power-off signal output from the operation panel 23 has been input. When the power off signal is not input, the ventilation control unit 62 returns to the process S3 and performs control according to the various input signals and the internal temperature T in the processes S3 to S12. On the other hand, when the power-off signal is input, each fan control unit 623, 624, 625 stops each axial flow fan 55, 56, 57 being driven (S14). And the control apparatus 6 complete | finishes a cooling process.

According to the present embodiment, since the second and third axial fans 56 and 57 are driven as necessary, for example, the amount of heat generated in the exterior casing 2 is small and the amount of ventilation inside and outside the exterior casing 2 is small. When it is acceptable (normal state), it can be stopped. In this case, since only the first axial fan 55 generates noise, the noise generated in the projector 1 in the normal state can be suppressed.
Since the first axial fan 55 is always driven, the pressure in the ventilation casing 51 is not reduced below the external pressure outside the exterior casing 2. Accordingly, it is possible to prevent air from flowing back from the outside of the outer casing 2 to the ventilation casing 51 and the storage chamber.
Further, since the constantly driven first axial fan 55 is provided on the inner side of the outer casing 2 through the ventilation casing 51, the driving of the first axial fan 55 felt by the user of the projector 1 is performed. The sound is smaller than the driving sound of the second and third axial fans 56 and 57. Therefore, noise generated in the projector 1 in the normal state can be suppressed.

Since the air flow directions of the first axial fan 55 and the second and third axial fans 56 and 57 are not aligned with each other, the light in the light source storage chamber 451 is transmitted to the first axial fan 55 and Leakage to the outside of the exterior housing 2 through the gap between the second and third axial fans 56 and 57 can be prevented.
Since a plurality of the openings 53 and 54 and the axial fans 56 and 57 are provided, the amount of ventilation between the exterior casing 2 and the ventilation casing 51 can be increased.
Furthermore, when the second and third axial fans 56 and 57 are driven, the second and third axial fans 56 and 57 can be appropriately selected and driven. Therefore, for example, fine ventilation adjustment can be performed, such as increasing or decreasing the ventilation amount between the outside of the exterior casing 2 and the inside of the ventilation casing 51 in stages, or changing the air volume according to the ventilation direction.

  Since the blowing directions of the second and third axial fans 56 and 57 are not positioned in a straight line with each other, the driving state of the second and third axial fans 56 and 57 can be adjusted to adjust the outer casing. The ventilation direction between the outside of the body 2 and the inside of the ventilation casing 51 can be changed. When exhausting the air in the ventilation casing 51 to the outside of the exterior casing 2 by the second and third axial fans 56 and 57 as in the present embodiment, the exhaust wind is adjusted by adjusting the exhaust direction. Can be prevented from hitting users and viewers.

When the internal temperature T in the light source storage chamber 451 is equal to or higher than the reference temperature T ₀ , the second axial fan 56 is driven. That is, when the internal temperature T is lower than the reference temperature T ₀ , that is, when the amount of heat generated in the light source storage chamber 451 is small, the second axial fan 56 is not driven and only the first axial fan 55 is driven. The Therefore, since only the noise due to the driving of the first axial fan 55 is present, the noise generated in the projector 1 in the normal state can be suppressed.
When the internal temperature T in the light source storage chamber 451 becomes equal to or higher than the reference temperature T ₀ , the second axial fan 56 is driven to drive the outside of the exterior casing 2 and the light source storage chamber 451 through the ventilation casing 51. The amount of ventilation can be increased. In this way, by increasing the ventilation rate, the light source device 411 in the light source storage chamber 451 can be cooled and the internal temperature T can be lowered.

[Modification of the embodiment]
The best configuration for implementing the present invention has been disclosed in the above description, but the present invention is not limited to this. That is, since the embodiment does not limit the present invention, description of the names of members excluding some or all of the limitations on the shape, material, etc. is included in the present invention. is there.

In the embodiment, an axial fan is used for each of the fans 55, 56, and 57. However, in the present invention, a sirocco fan may be used.
In the embodiment, the ventilation unit 5 is an exhaust unit that exhausts the air in the exterior casing 2 to the outside of the exterior casing 2. However, in the present invention, the air outside the exterior casing 2 is exhausted. An intake unit that intakes air may be used.
Specifically, the ventilation unit 5 of this modification is disposed in the vicinity of the optical device 44. Further, the first axial fan 55 has a suction port disposed opposite the first opening 52, and the second and third axial fans 56 and 57 have a first suction port communicating with the suction port of the exterior housing 2. 2 and the third openings 53 and 54 are arranged to face each other.

  According to such a configuration, the air outside the exterior housing 2 taken in by the ventilation unit 5 can be sent to the liquid crystal panel 441 and the polarization conversion element 414 to be cooled. Then, as in the above-described embodiment, by driving and stopping the second and third fans according to the temperature in the vicinity of the liquid crystal panel 441, the liquid crystal panel 441 and the polarization conversion element 414 can be appropriately cooled and driven by the fan. Noise can be suppressed.

In the above embodiment, when the internal temperature T in step S4 is determined to reference temperature T ₀ or more, only the second axial flow fan 56 is driven. However, in the present invention, the third axial fan 57 may be driven simultaneously with the second axial fan 56.
Each fan control unit 623, 624, 625 may adjust the rotational speed of each axial fan 55, 56, 57 according to the internal temperature T.
In the above embodiment, the temperature in the light source storage chamber 451 is compared with the reference temperature T ₀ as the internal temperature T. However, the temperature dominant in the light source storage chamber 451, the temperature around the light source device 44, or the surroundings of the first axial fan 52 The temperature may be the internal temperature T.

  In the above-described embodiment, the transmissive liquid crystal panel 441 is employed as the light modulation device. However, the present invention is not limited to this, and a reflective liquid crystal panel may be employed, or a digital micromirror device (Texas Instrument Trademark) may be employed.

1 is a schematic plan view showing an optical unit and a ventilation unit of a projector according to an embodiment of the invention. The perspective view which shows the ventilation | gas_flowing unit which concerns on the said embodiment. The block diagram which shows the functional structure of the control apparatus which concerns on the said embodiment. The flowchart for demonstrating the effect | action of the control apparatus which concerns on the said embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Projector, 2 ... Exterior casing, 21 ... Exhaust opening (exterior casing opening), 22 ... Exhaust opening (exterior casing opening), 3 ... Projection lens (projection optical apparatus), 411 ... Light source apparatus, 441, 441R , 441G, 441B ... Liquid crystal panel (light modulation device), 51 ... Ventilating housing, 52 ... First opening (inside opening), 53 ... Second opening (outside opening), 54 ... Third opening (outside opening) , 55 ... 1st axial fan (internal fan), 56 ... 2nd axial fan (external fan), 57 ... 3rd axial fan (external fan), 61 ... Input signal acquisition unit, 621 ... Temperature acquisition unit, 622 ... temperature determination unit, 623 ... first fan control unit, 624 ... second fan control unit, 625 ... third fan control unit, 7 ... temperature sensor, T ... internal temperature, T ₀ ... reference temperature ( Predetermined temperature).

Claims (6)

A light source device; a light modulation device that modulates a light beam emitted from the light source device according to image information to form an optical image; and a projection optical device that enlarges and projects the optical image formed by the light modulation device. , A projector comprising an exterior housing containing each of the devices,
An exterior housing opening formed in the exterior housing;
A ventilation housing provided in the exterior housing and having an internal opening that communicates with the interior of the exterior housing, and an external opening that communicates outside the exterior housing through the exterior housing opening;
An internal fan that is provided at the internal opening and allows air to flow between the exterior casing and the ventilation casing at all times during operation;
A projector, comprising: an external fan that is provided in the external opening and allows air to flow between the outside of the exterior casing and the inside of the ventilation casing as needed during operation. The projector according to claim 1, wherein
The internal fan and the external fan are axial fans,
The projector according to claim 1, wherein the blowing direction of the internal fan and the blowing direction of the external fan are not positioned on a straight line. In the projector according to claim 1 or 2,
A plurality of the external openings are formed,
The projector according to claim 1, wherein the external fan is provided in each of the plurality of external openings. The projector according to claim 3, wherein
The projector according to claim 1, wherein air blowing directions of at least two external fans among the plurality of external fans are not located on a straight line. In the projector according to any one of claims 1 to 4,
The internal fan has a discharge port disposed opposite the internal opening, and blows air in the exterior housing into the ventilation housing,
The projector according to claim 1, wherein the external fan has a discharge port disposed so as to face the external opening, and blows air in the ventilation casing to the outside of the exterior casing. In the projector according to any one of claims 1 to 5,
A temperature sensor provided in the exterior casing;
A temperature acquisition unit for acquiring the temperature in the exterior casing detected by the temperature sensor;
A temperature determination unit that determines whether or not the temperature in the exterior casing acquired by the temperature acquisition unit is equal to or higher than a predetermined temperature;
A projector comprising: a fan control unit that drives the external fan when the temperature determination unit determines that the temperature in the exterior casing is equal to or higher than a predetermined temperature.

Images