JP2835541B2 - Original 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 document projector using a heat-generating light source.

[0002]

2. Description of the Related Art Conventionally, in this type of projector, the temperature inside the projector is increased by turning on a light source, that is, a projection lamp during projection. Therefore, in order to suppress an excessive rise in temperature, the cooling fan is usually rotated to perform forced air cooling. Furthermore, if the cooling fan is stopped immediately after the projection is completed and the projection lamp is turned off, the temperature rises rapidly due to the residual heat of the projection lamp. is there.

Therefore, a thermostat is provided in the projector and a cooling fan is turned on to blow air until the contact is cut off, or a fan is turned on for a preset time after turning off the light (see JP-A-1-116535). Further, there is known an apparatus in which a fan is turned by a power supply of a different system from that of a projection lamp, and the fan continues to run as long as the power supply is connected even when the lamp is turned off.

[0004]

However, it is not possible to know how long it takes to cool the device, so that it is wasted time to clean up the projector and the like. The projector may be left ignorant of whether cooling has ended. In such a case, it is useless to keep the fan running for a certain period of time, for example, even when the projection time is short and the temperature inside the apparatus hardly rises. In addition, since the projection time becomes long and the heat accumulation of the projector itself increases, and furthermore, when the ambient temperature is high, it takes a long time to cool sufficiently. Not exclusively. Therefore, turning a fan for cooling for a limited time lacks versatility. Furthermore, in addition to the problems described above, since the end point of cooling is not clear, a wasteful point such as continuing to operate the fan after cooling is added.

An object of the present invention is to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide a document projector which calculates and displays a time required for cooling in consideration of environmental conditions. I do.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a temperature sensor for detecting at least the temperature inside a projector, a light source after projection based on a detection signal of the temperature sensor, and the inside of the projector. A configuration is provided that includes means for calculating and estimating the time required for cooling and display means for displaying the remaining time obtained by subtracting the elapsed time from the estimated time.

Further, a configuration is provided in which an informing means for informing the end of cooling is provided.

[0008]

According to the above construction, the remaining time until the predetermined cooling end temperature is reached is displayed every moment after the end of the projection and after the light is turned off, and the end of the cooling is notified by a sound or the like. The waiting time can be used effectively for another purpose.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments will be described below in detail with reference to the drawings. FIG. 1 shows a configuration of a portion for displaying a time required for cooling according to an embodiment of the present invention, wherein 1 is an input terminal, 2 is a microcomputer, 3 is an indoor temperature sensor for detecting an indoor temperature, and 4 is an indoor temperature sensor. A projector temperature sensor 5 for detecting the temperature inside the projector is a display.

The input terminal 1 is connected to, for example, a power switch of a projection lamp, a projection end switch, etc. in order to receive, as a signal, information on the state of the projector, that is, whether the projection is in progress or the projection has ended. The microcomputer 2 is connected to a room temperature sensor 3 and a projector temperature sensor 4.
Then, based on the signal from the input terminal 1, the time required for cooling is calculated and predicted, and the remaining time obtained by subtracting the elapsed time from the predicted time is displayed on the display 5.

The specific operation will be described with reference to the flowchart of FIG. First, the microcomputer 2 detects from the signal from the input terminal 1 whether or not the projector has finished the projection. If the projection has been completed, then the microcomputer 2 next arranges the projector near the projection lamp of the projector. It is determined whether the inside of the projector needs to be cooled based on a signal from the inside temperature sensor 4. This may be compared with a temperature set in the microcomputer 2 in advance.

If cooling is required, the microcomputer 2 sets the number of times determined within a certain period of time by the room temperature sensor 3 and the projector temperature sensor 4 arranged at positions not affected by the heat generated by the projection lamp of the projector. Sampling is performed, and the time required to reach the set temperature inside the projector at which the cooling is completed is calculated and predicted, and the time is displayed on the display unit 5, and the display time is subtracted as time elapses. The time when the display time becomes zero is the end point of the cooling. Therefore,
The temperature in the projector is detected and confirmed, and the process ends. FIG. 3 shows the cooling characteristics.

FIG. 4 shows another embodiment of the present invention, in which an alarm 6 for notifying the end of cooling is added to the embodiment of FIG. As indicated by the broken line in the flow chart of FIG. 2, when the inside of the projector reaches the cooling end temperature, the microcomputer 2 sends a signal to the alarm 6 and
Ring the alarm to signal the end of cooling.

In the embodiment, two temperature sensors, one for detecting the temperature inside the projector and the other for detecting the indoor temperature, are provided. However, it is possible to predict the cooling end time only by detecting the temperature inside the projector. is there. However, the temperature inside the projector to be cooled decreases gradually as the temperature approaches the room temperature. The more the predictions become, the more errors the prediction has, and there is no point in implementing it. Therefore, a correction for prediction is required by detecting the room temperature. FIG. 5 is a cooling characteristic diagram showing this state.

[0015]

As described above, according to the present invention,
After the projection is completed, the time required to cool the light source and the inside of the projector is displayed, so that the time until the cooling is completed can be known, and the waiting time until then can be effectively used for other things. You will be released from the mental pressure of whether the cooling is finished.

Further, since the completion of the cooling is notified by a sound, it is possible to concentrate on the work without being distracted by the visual clock display, so that the time until the completion of the cooling can be used more effectively. it can.

[Brief description of the drawings]

FIG. 1 is a block diagram of a portion for displaying a time required for cooling according to an embodiment of the present invention.

FIG. 2 is a flowchart of the embodiment.

FIG. 3 is a cooling characteristic diagram of the embodiment.

FIG. 4 is a block diagram of another embodiment of the present invention.

FIG. 5 is a cooling characteristic diagram of the embodiment.

[Explanation of symbols]

2 ... microcomputer, 3 ... indoor temperature sensor, 4 ... temperature sensor in projector, 5 ... display, 6
… An alarm.

Claims (2)

(57) [Claims] In a document projector using a heat-generating light source, a temperature sensor for detecting at least the temperature inside the projector, and the light source and the inside of the projector after completion of projection are cooled based on a detection signal of the temperature sensor. calculating the time required, and means for predicting, display means for displaying the remaining by subtracting the elapsed time from the time the predicted time, the projection ends, after off
In addition, the remaining time to reach the predetermined cooling end temperature is
A document projector characterized in that it is displayed every moment . 2. A document projector according to claim 1, further comprising a notifying unit for notifying the end of cooling.