JP2015059954A - Projector, air filter exchange control program and air filter exchange detection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable accurate determination of air filter clogging.SOLUTION: When detected illuminance is below theoretical illuminance P, it is estimated that illuminance of a light source part 11 has fallen with a temperature increase of an ambient temperature Ta. In this case, deviation from the theoretical illuminance P is read (step S9), and then, determination is made whether the read deviation amount is 80% or more with respect to the theoretical illuminance P (step S10). When the determination is YES, and the deviation amount is 80% or more, the actual illuminance of the light source part 11 has fallen greatly with respect to the theoretical illuminance P. Thus, it is estimated that in the light source part 11, the illuminance has fallen greatly due to a thermal influence generated by increase in an internal temperature. Further, it can be determined that the thermal influence generated by the increase in the internal temperature has been caused by clogging in an air filter 5. Thus, in a display part 16, an exchange alarm display is performed that prompts an exchange of the air filter 5 (step S11).

Description

  The present invention relates to a projector in which an air filter is disposed at an intake port provided in a housing, an air filter replacement control program used for the projector, and an air filter replacement detection method.

  2. Description of the Related Art Conventionally, in a projector using a semiconductor laser or the like as a light source, an air inlet is provided in a housing, and outside air is introduced into the inside by a fan from the air inlet to suppress a temperature rise in the housing. At this time, in order to prevent dust and dirt in the outside air from being introduced into the interior and adhere to the light source to reduce the illuminance, or to adhere to the circuit and cause a malfunction or malfunction, an air filter is installed in the intake port. Is installed.

  Therefore, as the usage time elapses, the air filter is clogged with dust and dirt in the outside air, the amount of air introduced into the housing is reduced, and the function of suppressing the temperature rise in the housing is reduced. . In order to notify the user of such clogging and prevent the temperature rise in the housing from being lowered, a temperature sensor for detecting the temperature in the housing is provided, and the temperature in the housing rises above the threshold value. In such a case, a technique for determining whether the air filter is clogged has been proposed (see, for example, Patent Document 1 below).

JP 2012-128282 A

  However, the cause of the temperature rise inside the housing of the projector is not limited to clogging of the air filter, but a heat source such as the light source unit and other disturbance elements act in a complicated manner. Therefore, even if the temperature change in the housing is detected by the temperature sensor, it is not certain whether the detection result indicates clogging of the air filter. Therefore, even if the air filter is determined to be clogged based on the temperature in the housing detected by the temperature sensor, a highly accurate determination result cannot be obtained.

  The present invention has been made in view of such conventional problems, and an object of the present invention is to provide a projector, an air filter replacement control program, and an air filter replacement detection method capable of accurately determining clogging of an air filter. To do.

In order to solve the above problems, a projector according to the present invention includes a housing, a light source disposed inside the housing, an air intake section provided in the housing, an air filter disposed in the air intake section, An illuminance detector that detects the illuminance of the light source, a temperature detector that detects the temperature inside the housing, the illuminance of the light source detected by the illuminance detector, and the temperature detected by the temperature detector , A determination unit that determines the clogged state of the air filter based on the relationship,
It is characterized by providing.

  An air filter replacement control program according to the present invention includes a light source disposed inside a housing, an air intake section provided in the housing, an air filter disposed in the air intake section, and an illuminance of the light source. A computer having a projector including an illuminance detection unit to detect and a temperature detection unit to detect the temperature inside the housing is detected by the illuminance of the light source detected by the illuminance detection unit and the temperature detection unit. It is made to function as a judgment part which judges the clogged state of the air filter based on the relation with the temperature.

  In addition, an air filter replacement detection method according to the present invention includes an air in a projector including a light source disposed inside a housing, an air intake section provided in the housing, and an air filter disposed in the air intake section. In the filter replacement detection method, an illuminance detection step for detecting an illuminance of the light source, a temperature detection step for detecting a temperature inside the housing, an illuminance of the light source detected by the illuminance detection step, and the temperature And a determination step of determining a clogged state of the air filter based on the relationship with the temperature detected by the detection step.

  ADVANTAGE OF THE INVENTION According to this invention, the clogged state of the air filter arrange | positioned at the inlet port which a projector has can be determined accurately.

1 is a block configuration diagram of a projector according to an embodiment of the invention. FIG. It is a schematic diagram which shows the process sequence in this Embodiment.

Hereinafter, embodiments of the present invention will be described.
FIG. 1 is a block configuration diagram showing a schematic configuration of a projector 1 according to an embodiment of the present invention. The projector 1 has a housing 2, and a ventilation opening 3 is formed on one end side of the housing 2, and a projection opening 4 is opened on the other end side. An air filter 5 is replaceably attached to the ventilation opening 3, and a projection lens 18 is fixed to the projection opening 4.

  A cooling fan 10 is disposed in the vicinity of the air filter 5, and a light source unit 11 that generates RGB color lights is provided at a downstream stage of the cooling fan 10. The light source unit 11 is, for example, a semiconductor laser, and a thermistor 12 for detecting the temperature inside the light source unit 11 itself or the housing 2 is attached. That is, the thermistor 12 may be configured to contact the light source unit 11 and detect the temperature of the light source unit 11, or detect the temperature of the internal space of the housing 2 without contacting the light source unit 11. It may be a configuration. In this specification, the temperature of the light source unit 11 detected by the thermistor 12 or the temperature of the internal space of the housing 2 is collectively referred to as an internal temperature.

  Further, the projector 1 is provided with a control unit 6, a video signal input unit 7, a video signal processing unit 8, and a video generation unit 9, a clock unit 13, a storage unit 14, an operation unit 15, and a display unit 16. And an illuminance sensor 17 are provided. The image signal (image data) of various standards input from the video signal input unit 7 is converted by the video signal processing unit 8 so as to be unified into an image signal of a predetermined format suitable for display, and then is input to the video generation unit 9. Sent. The video generation unit 9 develops and stores the transmitted image signal in the video RAM, generates a video signal from the stored contents of the video RAM, and outputs the video signal to the projection lens 18. The image is projected and displayed on a screen (not shown).

  The control unit 6 controls the operation of each circuit in the projector 1 and includes a CPU and its peripheral circuits, a storage unit 14 such as a ROM and a RAM. The storage unit 14 stores in advance programs such as various settings, programs and data shown by flowcharts described later, and is also used as a work memory or the like.

  The clock unit 13 is a circuit that generates a clock signal having a predetermined frequency, and the control unit 6 can count the usage time of the light source unit 11 based on the clock signal. The operation unit 15 includes various keys, and operation signals are sent to the control unit 6. The display unit 16 is configured by an indicator or the like disposed outside the housing 2.

  The illuminance sensor 17 detects the illuminance of the light source unit 11 directly or indirectly and supplies it to the control unit 6. That is, the illuminance detected by the illuminance sensor 17 may be a direct illuminance such as the surface of the light source unit 11 or the nearest position, or an indirect illuminance at a position away from the light source unit 11 by a predetermined distance, as illustrated. Any of the illuminance between the image generation unit 9 and the projection lens 18 may be used.

  FIG. 2 is a flowchart showing a processing procedure in the present embodiment. The control unit 6 executes processing as shown in this flowchart according to the program stored in the storage unit 14. That is, the controller 6 constantly monitors the state of the illuminance sensor 17 and determines whether or not the illuminance sensor 17 has detected an illuminance of a predetermined level or higher (step S1). If the illuminance sensor 17 detects an illuminance of a predetermined value or more, it is assumed that the light source unit 11 is in a lighting operation, and the usage time t is counted up (step S2). Therefore, the value “t” indicates the usage time of the light source unit 11 of the projector 1 up to the present time.

  Next, it is determined whether or not the illuminance detected by the illuminance sensor 17 exceeds the illuminance A (step S3). Here, the illuminance A is the lowest level of brightness in the on state that the light source unit 11 can take. If the detected illuminance is a value that does not exceed the minimum level illuminance A, a “light source removal prevention error” display is displayed on the display unit 16 to notify that the light source unit 11 is not properly fixed. (Step S4). Thereafter, the process proceeds to the STOP process, and the counting of the usage time t is stopped.

  On the other hand, when the detected illuminance exceeds the minimum level illuminance A, the internal temperature Ta detected by the thermistor 12 is read (step S5). Then, it is determined whether or not the read internal temperature Ta is equal to or higher than a predetermined threshold (step S6). If the determination in step S6 is NO and the read internal temperature Ta is less than a predetermined threshold, it can be assumed that the inside of the housing 2 and the light source unit 11 itself are in a normal temperature state. It can be estimated that the air filter 5 is not clogged. Therefore, the continuous operation is executed as it is (step S14).

However, if the determination in step S6 is YES and the read internal temperature Ta is equal to or higher than a predetermined threshold, the internal temperature Ta is high and the air filter 5 may be clogged. Therefore, in order to determine whether clogging the air filter 5 has occurred, after reading the operating current I _F flowing through the light source, the theoretical illumination P is the optical output based on the internal temperature Ta read in step S5 Is calculated (step S7).

An equation for obtaining the theoretical illuminance P is shown below.
P = P ₀ × exp (−βt) (1)
P ₀ : Initial light output β: Degradation rate t: Operating time

The deterioration rate β in the equation (1) is obtained as follows.
_{β = β 0 × I F ×} exp (-Ea / kTj) ······ (2)
β ₀ : Degradation constant (element specific)
_IF : Operating current I (A)
Ea: Activation energy (eV)
k: Boltzmann constant (8.62 × 10 ⁻⁵ ) (eV / K)
Tj: temperature of the light emitting layer

The temperature Tj of the light emitting layer in the formula (2) is obtained as follows.
Tj = (Rth × I _F × V _F ) + Ta (3)
Rth: Thermal resistance (° C / W)
V _F : Forward voltage (V)
Ta: Ambient temperature (K)

  Subsequently, it is determined whether or not the detected illuminance detected in step S1 is greater than or equal to the theoretical illuminance P (step S8). If the detected illuminance ≧ theoretical illuminance P, the illuminance decrease of the light source unit 11 due to the temperature increase of the ambient temperature Ta does not occur, and the air filter 5 is not clogged enough to be replaced. Presumed. Therefore, the continuous operation is executed as it is (step S14).

  However, if the detected illuminance is less than the theoretical illuminance P, it is estimated that the illuminance reduction of the light source unit 11 is caused as the ambient temperature Ta rises. Therefore, in this case, the deviation from the theoretical illuminance P is read (step S9). That is, the deviation between the theoretical illuminance P and the detected illuminance is read.

  Next, it is determined whether or not the read deviation is a deviation amount of 80% or more with respect to the theoretical illuminance P (step S10). If this determination is YES and the amount of deviation is 80% or more, the actual illuminance of the light source unit 11 is significantly lower than the theoretical illuminance P. Therefore, it is estimated that the illuminance of the light source unit 11 is greatly reduced due to the thermal effect accompanying the increase in internal temperature. Further, it can be determined that the thermal effect accompanying the increase in the internal temperature is caused by the clogging of the air filter 5. Accordingly, a replacement warning display for prompting replacement of the air filter 5 is displayed on the display unit 16 (step S11), the operation is stopped by stopping the operation, and the use time t is stopped.

  Therefore, it is possible to prevent the inside of the housing 2 from becoming an abnormally high temperature state due to the operation stop, and to prevent damage to circuits and the like due to the abnormally high temperature. Further, the replacement of the air filter 5 at an appropriate time is urged, and the temperature rise due to the clogging of the air filter 5 is prevented, and the proper temperature management of the projector 1 becomes possible.

  If the determination in step S10 is NO and there is no deviation of 80% or more, it is determined whether or not the read deviation has a deviation of 60% or more with respect to the theoretical illuminance P (step). S12). If there is a deviation of 60% or more, the display unit 16 displays a replacement notice to notify the replacement of the air filter 5 (step S13), but the operation is continued as it is (step S14). Therefore, the user can continue the projection without any trouble while recognizing that the air filter 5 should be replaced by the replacement notice display, and can appropriately replace the air filter 5 after the projection.

  As described above, in the projector 1 according to the present embodiment, the degree of change in actual illuminance with respect to the theoretical illuminance at that time is taken into consideration without determining whether the air filter 5 is clogged only by the increase in internal temperature. Make a decision. Therefore, it can be appropriately determined whether or not the temperature rise is caused by clogging of the air filter 5.

  In the embodiment, the replacement warning and the replacement notice are selectively performed depending on whether the deviation is 80% or more or 60% or more, so that appropriate notification according to the degree of clogging is made. It can be performed.

  Note that the percentage of deviation (80%, 60%) in the embodiment is merely an example, and other values may be used. Further, in the embodiment, the notification is performed by display on the display unit 16, but may be performed by a sound emitting unit such as a speaker.

  Furthermore, in the embodiment, the temperature is first checked in step S6, and when the temperature is equal to or higher than the threshold value, the determination is performed using the illuminance (steps S10 and S12). However, on the contrary, the determination using the illuminance (steps S10 and S12) may be performed first, and if each determination is YES, the determination of the temperature check (step S6) may be performed.

  Even in such a case, the determination is made in consideration of the actual degree of change in the illuminance with respect to the theoretical illuminance at that time without determining the clogging of the air filter 5 only by the increase in the internal temperature. Therefore, it can be appropriately determined whether or not the temperature rise is caused by clogging of the air filter 5.

As mentioned above, although embodiment of this invention was described, these are suitably changeable if it is in the range with which the effect of this invention is acquired, Embodiment after change is also invention described in the claim, And the scope of the invention equivalent to that invention.
The invention described in the scope of the claims of the present application will be appended below.

[Claim 1]
A housing,
A light source disposed inside the housing;
An air intake provided in the housing;
An air filter disposed in the intake section;
An illuminance detector for detecting the illuminance of the light source;
A temperature detector for detecting the temperature inside the housing;
A determination unit that determines a clogged state of the air filter based on a relationship between the illuminance of the light source detected by the illuminance detection unit and the temperature detected by the temperature detection unit;
A projector comprising:

[Claim 2]
The projector according to claim 1, further comprising a notification unit that notifies a determination result by the determination unit.

[Claim 3]
The determination unit determines a clogged state of the air filter based on the illuminance detected by the illuminance detection unit when the temperature detected by the temperature detection unit is equal to or higher than a threshold value. The projector according to claim 1 or 2.

[Claim 4]
When the temperature detected by the temperature detector is equal to or higher than a predetermined temperature and the illuminance detected by the illuminance detector is equal to or lower than a predetermined illuminance, the determination unit is clogged with the air filter. The projector according to claim 3, wherein the determination is performed.

[Claim 5]
The determination unit determines the clogged state of the air filter based on the temperature inside the housing detected by the temperature detection unit when the illuminance detected by the illuminance detection unit is equal to or less than a threshold value. The projector according to claim 1 or 2.

[Claim 6]
When the illuminance detected by the illuminance detection unit is equal to or lower than a predetermined illuminance and the temperature inside the casing detected by the temperature detection unit is equal to or higher than a predetermined temperature, the determination unit 6. The projector according to claim 5, wherein the projector is determined to be clogged.

[Claim 7]
The said determination part determines the presence or absence of clogging of the said air filter based on the difference of the illumination intensity detected by the said illumination intensity detection part, and theoretical theoretical illumination intensity obtained theoretically. The projector described.

[Claim 8]
A storage unit storing the theoretical illuminance;
The projector according to claim 7, wherein the determination unit reads the theoretical illuminance from the storage unit and determines whether the air filter is clogged.

[Claim 9]
A light source disposed inside the housing, an air intake section provided in the housing, an air filter disposed in the air intake section, an illuminance detection section that detects the illuminance of the light source, and a temperature inside the housing A computer having a projector comprising a temperature detection unit for detecting
Based on the relationship between the illuminance of the light source detected by the illuminance detection unit and the temperature detected by the temperature detection unit, the illuminance detection unit functions as a determination unit that determines a clogged state of the air filter. Air filter replacement control program.

[Claim 10]
An air filter replacement detection method in a projector, comprising: a light source disposed inside a housing; an air intake section provided in the housing; and an air filter disposed in the air intake section.
Illuminance detection step for detecting the illuminance of the light source;
A temperature detection step of detecting the temperature inside the housing;
A determination step of determining a clogged state of the air filter based on the relationship between the illuminance of the light source detected by the illuminance detection step and the temperature detected by the temperature detection step;
An air filter replacement detection method comprising:

DESCRIPTION OF SYMBOLS 1 Projector 2 Case 3 Ventilation opening part 4 Projection opening part 5 Air filter 6 Control part 7 Image | video signal input part 8 Image | video signal processing part 9 Image | video production | generation part 10 Cooling fan 11 Light source part 12 Thermistor 13 Clock part 14 Memory | storage part 15 Operation unit 16 Display unit 17 Illuminance sensor 18 Projection lens 141 Theoretical illumination table

Claims (10)

A housing,
A light source disposed inside the housing;
An air intake provided in the housing;
An air filter disposed in the intake section;
An illuminance detector for detecting the illuminance of the light source;
A temperature detector for detecting the temperature inside the housing;
A determination unit that determines a clogged state of the air filter based on a relationship between the illuminance of the light source detected by the illuminance detection unit and the temperature detected by the temperature detection unit;
A projector comprising:   The projector according to claim 1, further comprising a notification unit that notifies a determination result by the determination unit.   The determination unit determines a clogged state of the air filter based on the illuminance detected by the illuminance detection unit when the temperature detected by the temperature detection unit is equal to or higher than a threshold value. The projector according to claim 1 or 2.   When the temperature detected by the temperature detector is equal to or higher than a predetermined temperature and the illuminance detected by the illuminance detector is equal to or lower than a predetermined illuminance, the determination unit is clogged with the air filter. The projector according to claim 3, wherein the determination is performed.   The determination unit determines the clogged state of the air filter based on the temperature inside the housing detected by the temperature detection unit when the illuminance detected by the illuminance detection unit is equal to or less than a threshold value. The projector according to claim 1 or 2.   When the illuminance detected by the illuminance detection unit is equal to or lower than a predetermined illuminance and the temperature inside the casing detected by the temperature detection unit is equal to or higher than a predetermined temperature, the determination unit 6. The projector according to claim 5, wherein the projector is determined to be clogged.   The said determination part determines the presence or absence of clogging of the said air filter based on the difference of the illumination intensity detected by the said illumination intensity detection part, and theoretical theoretical illumination intensity obtained theoretically. The projector described. A storage unit storing the theoretical illuminance;
The projector according to claim 7, wherein the determination unit reads the theoretical illuminance from the storage unit and determines whether the air filter is clogged. A light source disposed inside the housing, an air intake section provided in the housing, an air filter disposed in the air intake section, an illuminance detection section that detects the illuminance of the light source, and a temperature inside the housing A computer having a projector comprising a temperature detection unit for detecting
Based on the relationship between the illuminance of the light source detected by the illuminance detection unit and the temperature detected by the temperature detection unit, the illuminance detection unit functions as a determination unit that determines a clogged state of the air filter. Air filter replacement control program. An air filter replacement detection method in a projector, comprising: a light source disposed inside a housing; an air intake section provided in the housing; and an air filter disposed in the air intake section.
Illuminance detection step for detecting the illuminance of the light source;
A temperature detection step of detecting the temperature inside the housing;
A determination step of determining a clogged state of the air filter based on the relationship between the illuminance of the light source detected by the illuminance detection step and the temperature detected by the temperature detection step;
An air filter replacement detection method comprising:

Images