JP2001022451A - Temperature controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a temperature controller controlling the driving of a fan, which corresponds to any temperature state on an ambient temperature and a temperature in a unit, controlling display and controlling power by using temperature difference information from plural temperature sensors. SOLUTION: A first temperature sensor 6a detects the ambient temperature in a unit easing part 2 or an outer part. A second temperature sensor 6b detects the temperature in a position where a temperature rise is predicted in the unit easing part. Detection temperature information is supplied to a control means 10. The control means 10 obtains temperature difference information from detection temperature information and recognizes a temperature state in the unit easing by using temperature difference information and controls a temperature control part 7, a display control part 9 and a power control part 8 in accordance with a temperature situation in the unit easing. Since various controls are executed in accordance with the temperature state in the unit easing part 2, the temperature in the unit easing part 2 can be cooled so that it is always stable. The temperature state is character-displayed and it can be recognized by a user. Even if the abnormality of a fault occurs, power supply can be stopped and therefore the unit can stably be used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic device having a lamp as a light source, such as a liquid crystal projector, and more particularly to a cooling device necessary for cooling the temperature inside the device which rises due to the influence of light emission of the lamp. Temperature control device.

[0002]

2. Description of the Related Art In general, projection-type devices such as liquid crystal projectors have been miniaturized while high definition and high luminance have been developed.

In order to achieve higher definition and higher brightness, it is conceivable to improve the luminous efficiency of a lamp used as a light source or to increase the light transmittance of a liquid crystal panel used.

However, when the luminous efficiency of the lamp is improved, the heat generated by the light emission of the lamp and the emitted light are converted into heat, so that the temperature inside the device rises and may become high. . Even when the light transmittance of the liquid crystal panel is increased, the amount of light transmitted through the liquid crystal panel increases, so that both surfaces of the liquid crystal panel are affected by optical members such as polarizing plates disposed on the light incident surface side and the light exit surface side. Temperature rises, and as a result, the temperature inside the device may become high. For this reason, if the temperature inside the device becomes high,
There is a possibility that the operation in the device is affected and the displayed image is adversely affected.

Therefore, in this type of liquid crystal projector,
Conventionally, a cooling device including a fan is provided in the device, and the hot air in the device is released to the outside by using a blowing action of the fan (the blowing may be applied to a member that directly rises in temperature. (A) Cools the inside of the equipment.

In general, such a cooling device is equipped with a temperature control device, which controls the rotation of a fan or the like or the power supply to control the temperature inside the device.

[0007] Such a temperature control device usually has a temperature sensor, and based on temperature information from the temperature sensor,
Control means for controlling a fan control by controlling a drive control unit for controlling driving of the fan, or controlling a warning display by controlling a display control unit for displaying character information such as a warning message on a display unit; (Microcomputer).

In such a temperature control device, if the temperature in the device rises due to the light emission of the lamp as described above and reaches a temperature (predetermined temperature) that affects the operation in the device, the temperature sensor This temperature is detected, and this temperature information is supplied to the control means. Then, the control means recognizes from the temperature information that the temperature inside the device has reached a predetermined temperature, and at the same time, controls the rotation of the fan by the drive control unit and the display unit by the display control unit in order to reduce the temperature inside the device. Display control such as a warning message. At this time, if the temperature in the device does not decrease even after performing the cooling or the display, the control unit may perform control to cut off the power supply of the device.

In this way, when the temperature inside the device rises, the temperature inside the device is lowered, so that malfunction of the device and deterioration of display performance are prevented, and the performance of the device is maintained.

However, in such a conventional temperature control device, the temperature at a specific point is detected by a temperature sensor, and based on the temperature information, air blowing cooling by a fan, a warning message by a display unit, or power-off control is performed. Therefore, there is a problem that it is not possible to perform control corresponding to all temperature conditions such as the ambient temperature and the temperature in the device.

[0011]

As described above, in the conventional temperature control device, the air cooling by the fan, the warning message by the display unit, or the power-off control is performed based on the temperature information from the temperature sensor. There has been a problem that control corresponding to all temperature conditions of the ambient temperature and the temperature in the device cannot be performed.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and uses a temperature difference information from a plurality of temperature sensors to drive a fan corresponding to all temperature conditions such as a peripheral temperature and a temperature in a device. It is an object to provide a temperature control device capable of performing control, display control, and power supply control.

[0013]

A temperature control device according to the present invention has a light source disposed in an equipment housing, and a fan mounted near the light source for suppressing a rise in temperature inside the equipment housing. Cooling means, a temperature control unit that controls the rotation of the fan to adjust the temperature inside the device housing,
A power supply for operating the device;
A power control unit for controlling turning off; a first temperature sensor attached to a first position of the device housing so as to detect a temperature of a peripheral portion of the device housing; A second temperature sensor attached to a second position where a rise is expected, and temperature information detected by the first and second temperature sensors are input, and the first position and the second position are detected. Control means for calculating a temperature difference and controlling at least one of the temperature control unit and the power supply control unit in accordance with a temperature state in the device housing.

In the present invention, by providing the first and second temperature sensors, the temperature of the peripheral portion of the equipment housing and the temperature at least at the position where the temperature rise is expected inside the equipment housing are detected. can do. The detected temperature information is compared by the control means to obtain temperature difference information, and by using this temperature difference information, the temperature state in the device housing can be recognized. Further, the control means controls at least one of the temperature control section and the power supply control section in accordance with the temperature condition in the equipment housing, so that the temperature in the equipment housing can be controlled to be within an allowable value. Further, the temperature state can be reported as needed. Furthermore, when an abnormality such as a failure occurs, the power can be turned off.
It is possible to obtain equipment reliability.

[0015]

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a temperature control device according to the present invention, and showing a schematic configuration of a temperature control device incorporated in an equipment housing.

As shown in FIG. 1, a temperature control device 1 according to the present embodiment is mounted inside an apparatus housing 2 such as a liquid crystal projector using a lamp as a light source, and includes a cooling device such as a fan 3. It is composed of

As a specific configuration, the temperature control device 1
Is a fan 3 as a cooling means, a power supply 4, a display unit 5 such as an LCD which can display a warning message, at least two first and second temperature sensors 6a and 6b, and a rotation of the fan 3. A temperature control unit 7 for controlling the temperature inside the device by controlling the power supply, a power supply control unit 8 for controlling on / off of the power supply 4, and a display control unit 9 for controlling the display of the character display by the display unit 5. And a control unit 10 for controlling the temperature control unit 7, the power supply control unit 8 and the display control unit 9 based on the temperature information detected by the temperature sensors 6a and 6b.

The fan 3 is arranged in the vicinity of an optical member such as a liquid crystal panel or a polarizing plate to which light from a lamp is irradiated, or in a place where the gas inside the device is easily blown to the outside, and is not shown. Wind is generated by rotating the fan 3 by the driving means. The rotation control of the fan 3 is controlled by a temperature control unit 7.

The power supply 4 turns on / off a power supply voltage to be supplied to a main circuit or the like in the device by an electric switch. By turning off the switch, the supply of power to the main circuit is stopped. be able to. The switch of the power supply 4 is switched and controlled by a power supply control unit 8.

The display unit 5 is capable of displaying characters such as a message or a warning message according to the temperature condition in the device. The display of the characters or the display or change of the characters is controlled by the display control unit 9. It has become so.

In the temperature control apparatus 1 according to the present embodiment, the control means 10 controls the temperature control unit 7 and the power supply control based on temperature information detected by at least two first and second temperature sensors 6a and 6b. It is characterized in that the unit 8 and the display control unit 9 are controlled.

Of the first and second temperature sensors 6a and 6b provided in the present embodiment, the first temperature sensor 6a is provided inside the device housing 2 so as to detect a temperature close to the ambient temperature in the device. Alternatively, it is arranged at a predetermined external position. On the other hand, the second temperature sensor 6b is arranged at a portion that generates a high temperature inside the device, for example, at a peripheral portion of an optical member such as a liquid crystal panel or a lamp.

The third, fourth,... Temperature sensors may be additionally provided at other portions having different temperatures as needed.

By providing the temperature information at a plurality of locations to the control means 10 by comparing the temperatures at the respective locations, it is possible to control the temperature in accordance with the use condition of the equipment.

The control means 10 is constituted by, for example, a microcomputer. The microcomputer 10 calculates the temperature difference from the detected temperature information from the first and second temperature sensors 6a and 6b as described above, and The temperature control unit 7 recognizes the temperature state inside the device and controls the temperature control unit 7 so that the temperature inside the device is optimized according to the recognition result. At this time, the microcomputer 10 records control contents corresponding to the temperature difference in a memory in advance, and uses the control map for each temperature difference information to perform optimal control (temperature control, temperature control, etc.) according to the calculated temperature difference information. (Display control or power control). If necessary, the microcomputer 10 controls the display control unit 9 to display an optimal warning message according to the temperature condition, or, when it is determined that the emergency is required, the power control unit 8.
Is controlled so that the power supply 4 is turned off.

Next, the operation of the temperature control device shown in FIG. 1 will be described in detail.

The case where the ambient temperature is normal (ambient temperature T1 = approximately 25 ° C.) and the case where the ambient temperature is high (high temperature T2 = approximately 40 ° C.) will be described. The description will be made on the assumption that T is 20 ° C., and that the operation upper limit temperature T3 of the device temperature is 50 ° C.

Now, it is assumed that the ambient temperature has become high. Then, when the ambient temperature is approximately 40 ° C., since the first temperature sensor 6a is installed at a location close to the ambient temperature, the temperature detected by the first temperature sensor 6a is T6a.
Is T6a = T2 = 40 ° C. In addition, since the second temperature sensor 6b is installed in a place where the temperature is high even in the device, the temperature T6b detected by the second temperature sensor 6b
Is T6b = T2 + ΔT = about 60 ° C.

In such a case, since the ambient temperature is high, the internal temperature T6b exceeds the maximum operation temperature T3 = 50 ° C. Therefore, if this state is maintained, the device may malfunction and the display performance may be adversely affected.

Therefore, the control means 10 (microcomputer) recognizes the temperature state in the device based on the temperature information from the first and second temperature sensors 6a and 6b, and based on the recognition result, the rotational speed of the fan 3 ( The temperature control unit 7 is controlled so as to increase the amount of air blown to reduce the temperature inside the device. Note that, as described above, when the internal temperature of the device exceeds the operation upper limit temperature, the rotation speed of the fan 3 is higher than that of the normal operation, and the blowing amount is increased accordingly. It is possible to cool faster than usual.

At this time, the control means 10 controls the display control unit 9 to display, for example, a character indicating that the ambient temperature is high on the display unit 5 as a warning message. This makes it possible for the user to recognize the temperature state in the device and to warn the user to move the device to another place of use.

Next, the case where the ambient temperature is normal will be described.

Now, it is assumed that the ambient temperature is about 25 ° C., which is normal. Then, since the first temperature sensor 6a is installed at a location close to the ambient temperature, the temperature T6a detected by the first temperature sensor 6a is T6a = T1 = 25 ° C. Further, since the second temperature sensor 6b is installed at a high temperature location in the device, the temperature T6b detected by the second temperature sensor 6b is T6b = T1 + ΔT = 4.
It is about 5 ° C.

In such a case, the ambient temperature is set to the normal 2
Since the temperature is 5 ° C., the in-device temperature T6b is significantly lower than the operation upper limit temperature T3 = 50 ° C. Accordingly, there is no need to cool the device since there is no particular effect on the operation of the device.

For this reason, the control means 10 recognizes this temperature state based on the temperature information from the first and second temperature sensors 6a and 6b, and at the same time, sets the rotation speed (blowing amount) of the fan 3 to the normal mode. To control the temperature control unit 7. In this case, the rotation of the fan 3 may be controlled intermittently as necessary for power saving.

At this time, the control means 10 controls the display control section 9 to cause the display section 5 to display, for example, characters indicating that the ambient temperature is normal. This allows the user to continue using the device with peace of mind.

By the way, it is conceivable that the cooling function breaks down for some reason. For example, this is a case where the fan 3 does not operate normally or stops due to a complete failure. Even in such a case, the temperature control device 1 of the present embodiment can cope.

Now, it is assumed that the fan for cooling the optical member or the lamp has failed. Then, since the first temperature sensor 6a is installed at a location close to the ambient temperature, the temperature T6a detected by the first temperature sensor 6a
Is T6a = T1 = 25 ° C., but the temperature of the second temperature sensor 6b locally rises because the fan 3 does not operate normally, and the original normal temperature rise △
This will greatly exceed T = 20 ° C. For example, assuming that the temperature rise ΔT at this time is 30 ° C., the detected temperature T6b of the second temperature sensor 6b is T6b = T1
+ ΔT = about 55 ° C.

In such a case, although the ambient temperature is low, the device internal temperature T6b becomes the operating upper limit temperature T3 = 50 ° C.
In this case, cooling cannot be performed, and further temperature rise is predicted. Therefore, it is necessary to immediately stop power supply.

Therefore, the control means 10 recognizes the temperature state in the device based on the temperature information from the first and second temperature sensors 6a and 6b, and shifts to an emergency mode such as failure occurrence based on the recognition result. I do. That is, the control unit 10 controls the power supply control unit 8 to turn off the power supply 4.
As a result, the power supply of the device is all stopped, so that it is possible to prevent the device from being fired when an abnormality occurs.

At the same time, the control means 10 causes the display control section 9 to cause the display section 5 to display, for example, a character indicating that an abnormality has occurred in the device as a warning message. This allows the user to immediately recognize the abnormality that has occurred in the device. In addition, even when the fan is rotating normally, the case where the ventilation hole is closed can be dealt with in the same manner as in the case of the above failure.

Therefore, according to the present embodiment, the ambient temperature and the internal temperature of the device are detected by at least two first and second temperature sensors 6a and 6b, and the detected temperature information is sent to the control means 10. By supplying the power, the control unit 10 recognizes the temperature state in the device, and thus can control the drive of the fan 3 and display control of a warning message or the like according to the temperature condition in the device. Further, when an abnormality such as a failure occurs, it is possible to recognize the abnormality and stop the power supply. Therefore,
Since the temperature inside the device can be kept within the allowable value, stable operation can be performed and the display performance of the liquid crystal does not deteriorate. In addition, since the device can be used with a sense of security, reliability can be obtained for the user.

In the embodiment of the present invention, an example has been described in which characters such as a warning message are displayed as means for giving the user a temperature state in the apparatus. However, the present invention is not limited to this. A voice means for notifying the user of the warning message by voice may be provided. This allows the user to more reliably recognize the temperature state of the device.

[0045]

As described above, according to the present invention,
Provided is a temperature control device capable of performing drive control, display control, and power supply control of a fan corresponding to all temperature conditions such as an ambient temperature and a temperature in a device by using temperature difference information from a plurality of temperature sensors. Becomes possible.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a temperature control device according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Temperature control device, 2 ... Equipment housing part, 3 ... Fan, 4 ... Power supply, 5 ... Display part, 6a ... First temperature sensor, 6b ... Second temperature sensor, 7 ... Temperature control part, 8 ... Power supply control unit, 9: display control unit, 10: control means (microcomputer).

Claims (3)

[Claims] A light source disposed in an equipment housing; a cooling means attached near the light source and having a fan for suppressing a rise in temperature inside the equipment housing; and controlling a rotation of the fan to control the rotation of the fan. A temperature control unit that adjusts a temperature inside the device housing; a power supply for operating the device; a power control unit that controls on / off of the power supply; and a temperature of a peripheral portion of the device housing. A first temperature sensor attached to a first position of the device housing; a second temperature sensor attached to at least a second position in the housing where a temperature rise is expected; 1, temperature information detected by a second temperature sensor is input, a temperature difference between the first position and the second position is calculated, and the temperature control unit and the power supply are set according to a temperature state in the device housing. At least one of the controls Temperature control device being characterized in that comprises a control means for controlling the. 2. A notifying means for notifying a warning message is further provided in the device housing, and when the temperature difference between the first position and the second position exceeds a predetermined value, the control unit sets the notifying device. The temperature control device according to claim 1, wherein control is performed to issue a warning message from the means. 3. The temperature control device according to claim 1, wherein the second temperature sensor is disposed near the light source.