JP2003091047A - Projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain balance between noise reduction in a product and prolongation of the life of the components of a projector by changing the number of rotation of a cooling fan in the projector in response to the arrangement state of the projector. SOLUTION: The projector is provided with an object to be cooled comprising a lamp being a light source and the cooling fan for cooling the object to be cooled. The projector includes a switch for setting the first number of rotation of the cooling fan, which basically satisfies the temperature rating of the object to be cooled, and also setting the second number of rotation of the cooling fan, which is faster in speed than the cooling fan rotation number. A detecting means for detecting the projector arrangement state is disposed and, then, the cooling fan rotation number is controlled in response to the arrangement state of the projector by changing-over the switch based on the output of the detecting means. Besides, the switch is changed-over into the second cooling fan rotation number when the detecting means detects the rear surface arrangement projecting state of the projector.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projector for projecting an image, and more particularly to rotation control of a cooling fan of the projector.

[0002]

2. Description of the Related Art In a projector, a lamp is used for projecting on a screen.
Since the panel and other parts become hot, a cooling fan is used to cool them so that they are within the temperature ratings of the parts.

As a method of installing the projector,
Various installation states such as front-mounted state, ceiling-mounted state, rear-side mounted projection state, rear-side suspended projection state are possible, and the function to flip the screen upside down or left-right so that the image stands upright according to the installation state. It is common to have one, and this is realized by electrically changing the scanning direction of the panel.

As a conventional technique for cooling a lamp, Japanese Unexamined Patent Publication No. Hei 9 (1998)
No. 304835 can be mentioned. This publication discloses a technique for cooling a lamp that can be used in both a stationary state and a suspended state. Specifically, referring to FIG. 7, a lamp light emission used as a light source is disclosed. An upper movable fin 114 and a lower movable fin 115 that restrict the flow of air by the air blowing unit that blows to the tube 101 in a direction that reduces the temperature difference between the upper and lower sides of the lamp arc tube are provided. The cooling air is effectively used by bounced back toward the upper part of the lamp arc tube by the upper and lower movable fins. In FIG. 7, 127 and 129 represent fin portions of the upper and lower movable fins, respectively.
28 and 130 are the weights of the respective fins. The G position of the upper movable fin 114 is the operating state when the A direction is the "top" direction, and the H position is the operating state when the A direction is the "ground" direction.

Further, in Japanese Unexamined Patent Publication No. 2001-21999, referring to FIG. 8, in view of the fact that thermal protection using a temperature sensor makes it difficult to perform appropriate thermal protection when the projector installation state changes, an inclination sensor is used. The installation status of the projector is determined using the tilt information from and the appropriate heat treatment protection (protection by cooling using the intake fan and exhaust fan) according to the installation status of the projector based on the temperature information from the temperature sensor. It is disclosed that this is done automatically.

Further, in Japanese Unexamined Patent Publication No. 8-201916, referring to FIG. 9, the temperature of a lamp and a liquid crystal display panel to be cooled are detected by temperature sensors 1 and 2, and a fan is detected based on the temperature detection results. It is disclosed that the rotation speeds of the fans 1 and 2 are controlled to set the rotation speeds of the fans 1 and 2 to the minimum necessary rotation speeds, respectively, to reduce the noise of the fans 1 and 2.

[0007]

Although the prior art has a function of changing the rotation speed of the internal cooling fan depending on the temperature, the cooling structure by the cooling fan is the same even when the installation state of the projector is changed. Because
The cooling fan speed was set to the limit at which the temperature rating of internal parts was satisfied. The reason for setting in this way is that if the rotation speed of the cooling fan is increased, a large margin can be secured for the temperature rating of the internal parts, but if the rotation speed is increased, the noise generated from the cooling fan which is uncomfortable for the user will also occur. This is because it becomes large as well.

However, depending on the installation state of the projector, even if the rotation speed is increased, the noise generated from the cooling fan may not be noticeable. Since the rotation speed is set to the limit that satisfies the rating, even in installation conditions where noise generated from such a fan is not a concern,
There is a problem that the life of the parts is shortened because the temperature is set to the limit of the temperature rating of the parts.

An object of the present invention is to change the number of rotations of the cooling fan of the projector in accordance with the installed state of the projector to balance the noise reduction of the product and the life extension of the components of the projector.

[0010]

In order to solve the above problems, the present invention adopts the following configurations. In a projector including a cooling target including a lamp as a light source, and a cooling fan that cools the cooling target, a first cooling fan rotation speed that satisfies a temperature rating of the cooling target to a necessary minimum. And a switch for setting a second cooling fan rotation speed that is faster than the first cooling fan rotation speed, a detection means for detecting the installation state of the projector, and an output of the detection means. A projector that controls the rotation speed of a cooling fan corresponding to the installation state of the projector by switching the switch according to.

Further, in the projector, when the detecting means detects the rear surface stationary projection state of the projector, the projector switches the switch to the second cooling fan rotation speed.

Further, in a projector provided with a cooling object including a lamp as a light source and a cooling fan for cooling the cooling object, a first object for satisfying a temperature rating of the cooling object to a necessary minimum. Means for extracting a switching signal for switching the screen scanning direction by providing a switch for setting the second cooling fan rotation speed which is faster than the first cooling fan rotation speed while setting the cooling fan rotation speed A projector for controlling the number of rotations of the cooling fan according to the installation state of the projector by switching the switch according to the output of the means.

Also, in the projector, the switch is switched to the second cooling fan rotation speed when the output of the means corresponds to the rear surface stationary projection state of the projector.

[0014]

DETAILED DESCRIPTION OF THE INVENTION A projector device according to an embodiment of the present invention will be described below with reference to FIGS.
FIG. 1 is a diagram showing a rear surface stationary installation state of the projector, and FIG. 2 is a diagram showing a front surface stationary installation state of the projector. FIG. 3 is a diagram showing the screen (panel) scanning direction in the projector rear surface stationary state, and FIG. 4 is a diagram showing the screen (panel) scanning direction in the projector front surface stationary state. Further, FIG. 5 is a diagram showing the relationship between the rotation speed of the cooling fan and the component life and the cooling fan noise. FIG. 6 is a diagram showing a configuration block for controlling the rotation speed of the cooling fan.

Here, 1 is a projector, 2 is a screen, 3 is a viewer ,, is a screen (panel) scanning direction, 4 is a switch (SW), 5 is a control microcomputer, 6 is a panel drive circuit, and 7 is a liquid crystal. Panel, 8 is a motor driver,
Reference numeral 9 represents a cooling fan, respectively.

As a method of installing the projector, there are a rear stationary projection state and a rear ceiling projection state as shown in FIG. 1, and a front stationary state and a ceiling suspension state as shown in FIG.
Although various installation states are assumed, the screen is turned upside down and the screen is turned left and right in order to correspond to the erect image in any installation state.

Correspondence to an upright image is realized by electrically changing the scanning direction of the panel. For example, in the case of the front surface stationary projection state of FIG. 2, as shown in FIG.
.. The panel is scanned in the order of ...
In the case of the rear stationary projection state of, as shown in FIG.
It is realized by scanning the panel in the order of ... And the direction of the arrow. That is, the scanning direction of the panel is set according to each installation state of the projector.

Regarding noise caused by the cooling fan, for example, in the case of rear projection, as shown in FIG. 1, since the projector 1 is projected from the back surface of the screen 2, the user 3 who looks at the screen 2 can sufficiently project the projector 1. And the noise generated from the cooling fan 9 is not noticeable at all.

On the other hand, as shown in FIG. 2, in the front stationary state, the projector 1 is projected from the surface of the screen 2, so that the user 3 who views the screen 2 and the projector 1 are arranged close to each other. The noise generated from the fan 9 is very noticeable.

In the conventional example, when the arrangement in the front stationary state is the strictest in terms of quiet design of the projector 1, the temperature rating of the most strict temperature component should be within the limit (in the components). Cooling design is done regardless of the projector installation condition, so that the lowest temperature rating can be finally cleared.

FIG. 5 shows the rotation speed of the cooling fan 9 and
The relationship between the life of the internal parts and the noise value of the cooling fan is shown, and the temperature rating of the internal parts is barely reached in the installation condition where the fan 9 noise in FIG. 2 is a concern at x rotation (r.p.m.). In a certain case (when the temperature rating can be finally cleared), the noise value L (dB) is set, and the projector 1 is designed so that this value has a cooling structure that does not cause the user 3 to feel uncomfortable.

Here, if the number of rotations is changed to y rotations (r.p.m.), the temperature of the internal parts can be further lowered, and the life of the internal parts is improved from a (H) to b (H). Although it is possible, the noise also increases from L (dB) to M (dB), which makes the user 3 feel uncomfortable.

In the conventional example, even if the fan 9 noise is not annoying as shown in FIG. 1, the fan 9 noise is annoying as shown in FIG. Since the control is performed by the set x rotation (r.p.m), there is a problem that the life is shortened to a (H) even though the user does not feel uncomfortable even with the y rotation originally.

FIG. 6 shows an example of a structure for increasing the rotation speed of the cooling fan 9. In this configuration example, a method of increasing the input voltage in order to increase the rotation speed of the cooling fan 9 will be described.

In FIG. 5, the number of revolutions x the number of revolutions (rpm)
Is set as a voltage VL, a voltage that gives a rotation speed y rotation (r.p.m) is VH, and a switch SW4 capable of switching the rotation speed according to the installation method of the projector 1 is provided, that is, the installation state of the projector ( For example, when a detection unit for detecting the rear-side stationary projection state shown in FIG. 1 or the front-side stationary state shown in FIG. 2) is provided and the noise of the cooling fan 9 shown in FIG. Rotation speed x rotation (r.
p. m), and when the noise of the cooling fan 9 shown in FIG. 1 is not a concern, the rotation speed y rotation (r.p.m) is given by switching the switch to the other by the installation state detecting means.

Here, the installation state detecting means of the projector uses a signal in the scanning direction of the screen (panel) as shown in FIGS. 3 and 4, or is an inclination sensor for detecting the inclination state of the projector. Alternatively, it is an appropriate means for detecting the front installation and the rear installation of the projector.
In this case, the installation state of the projector may be visually checked (whether it is the rear surface or the front surface), and in the case of the rear surface installation, the switch number may be manually switched so that the rotation speed is y rotations.

The switch SW4 can be switched by using the signal of the control signal line for switching the scanning direction of the panel 7. For example, in the case of the front-side stationary projection state of FIG. 2, the panel is scanned in the order of FIG. 4 and the direction of the arrow shown in FIG. 4, and in the case of the rear-side stationary projection state of FIG. Since the panel is scanned in the order of, ..., And in the direction of the arrow (in order to correspond to the upright image), the switch SW4 is switched using this switching signal in the screen scanning direction.

As described above, in the installation state in which the noise of the cooling fan shown in FIG. 1 is not annoying, the rotational speed in FIG. 5 is set to y. It can be improved from a (H) to b (H). Further, this switching is automatically switched by the projector installation state detecting means or a switching signal for setting the screen display state, that is, a signal for switching the scanning direction of the panel (g in FIG. 6). There is an advantage that a person can obtain a long service life of the component without performing any operation.

Here, conventionally, it is general to control the rotation speed of the cooling fan, but it detects the internal temperature and the ambient temperature, and the rotation speed of the cooling fan is minimized as long as the temperature is allowable. It is obvious that the method is different from the method for controlling the rotation of the cooling fan shown in the present invention, because it is a method for reducing the cooling fan to maintain the component life. That is, according to the present invention, since the rotation speed of the cooling fan is switched in the installed state, it can be said that the life of the component is further improved in addition to the conventional maintenance of the component life. Although the method of controlling the rotation speed of the fan is described as a method of switching the voltage in two stages in the present embodiment, a method of linearly switching may be used.

[0030]

According to the present invention, when the noise of the cooling fan is not a concern due to the installed state of the projector, it is possible to increase the rotation speed of the cooling fan in order to extend the life of the internal parts. It is possible. Furthermore, by automatically changing the rotation speed of the cooling fan to the optimum value based on the switching signal that sets the screen display state according to the projector installation state, the product's noise reduction and longevity can be adjusted according to the installation state. It is possible to balance the lifespan of the projector, and it is possible to provide a projector that is easy to use.

[Brief description of drawings]

FIG. 1 is a diagram showing a rear surface stationary installation state of a projector.

FIG. 2 is a diagram showing a front surface stationary installation state of the projector.

FIG. 3 is a diagram showing a screen (panel) scanning direction in a state where the projector rear surface is stationary.

FIG. 4 is a diagram showing a screen (panel) scanning direction in a stationary state of the front surface of the projector.

FIG. 5 is a diagram showing a relationship between a rotation speed of a cooling fan, a component life, and a cooling fan noise.

FIG. 6 is a diagram showing a configuration block for controlling the rotation speed of a cooling fan according to the present embodiment.

FIG. 7 is a diagram showing a configuration example of cooling fan control in a conventional technique.

FIG. 8 is a diagram showing another configuration example of cooling fan control in the conventional technique.

FIG. 9 is a diagram showing still another configuration example of the cooling fan control in the conventional technique.

[Explanation of symbols]

1 projector 2 screen 3 users 4 switch (SW) 5 control microcomputer 6 panel drive circuit 7 LCD panel 8 motor driver 9 Cooling fan ,, screen (panel) scanning direction

Claims (4)

[Claims] 1. A projector provided with a cooling target including a lamp as a light source and a cooling fan for cooling the cooling target, comprising: The cooling fan rotation speed of the
A switch for setting a second cooling fan rotation speed faster than the cooling fan rotation speed is provided, detection means for detecting the installation state of the projector is provided, and the switch is switched according to the output of the detection means to switch the projector. A projector that controls the rotation speed of a cooling fan corresponding to the installation state of the projector. 2. The projector according to claim 1, wherein the switch is switched to the second cooling fan rotation speed when the rear-side stationary projection state of the projector is detected by the detection means. 3. A projector provided with a cooling target including a lamp as a light source and a cooling fan for cooling the cooling target, comprising: a first cooling target for cooling the cooling target. The cooling fan rotation speed of the
Is provided with a switch for setting a second cooling fan rotation speed that is faster than the cooling fan rotation speed, a means for extracting a switching signal for switching the screen scanning direction is provided, and the switch is switched by the output of the means. A projector characterized by performing rotation speed control of a cooling fan corresponding to the installation state of the projector. 4. The projector according to claim 3, wherein the switch is switched to the second cooling fan rotation speed when the output of the means corresponds to a backside stationary projection state of the projector. .