JP4544186B2 - Lighting control device - Google Patents

Description

  The present invention relates to an illumination control apparatus that instructs the illumination apparatus to perform dimming control of a light source.

  Conventionally, as shown in FIG. 4, at least one (4 in the figure) lighting device 2 for turning on a light source (not shown), and a floor surface FL or a desk surface DE illuminated by the light source, etc. It is connected to an illuminance sensor 3 that detects the illuminance by reflected light IR and ER reflected by the illumination surface, and instructs the lighting device 2 to adjust the dimming ratio of the light source so that the output of the illuminance sensor 3 approaches the target value. An illumination control device 1 that outputs a control signal is provided (for example, see Patent Document 1). For example, a fluorescent lamp or a light emitting diode is used as the light source. As the illuminance sensor 3, for example, a sensor having a PIN photodiode is used, and the direct incidence of the light ID of the light source is blocked by a cover or the like so that only the reflected light IR, ER on the illuminated surface is incident. The control signal is, for example, a PWM signal having a duty ratio corresponding to the specified dimming ratio. Here, the dimming ratio indicates the ratio of the luminous flux of the light source to the luminous flux at the time of rated lighting.

  In general, the illuminance sensor 3 is not disposed on the illuminated surface, and is integrated with the illumination control device 1 fixed to the ceiling surface CE or integrated with the illumination device 2 as in the example of FIG. However, since the illuminance of the ceiling surface CE by the reflected light IR and ER on the illuminated surface is proportional to the illuminance of the illuminated surface (hereinafter referred to as “illuminated surface illumination”), the output of the illuminance sensor 3 is constant as described above. If the feedback control is performed as described above, the illuminated surface illuminance can be made constant.

  According to the illumination control device 1 described above, when there is external light ED that is light other than the light ID of the light source, such as sunlight entering from the window W, the light output of the light source can be suppressed by the illuminance by the external light ED. As a result, power consumption can be reduced.

  However, if the target value is constant, the conditions such as the reflectance of the illuminated surface and the distance between the illuminated surface and the illuminance sensor 3 are changed by changing the layout, such as wallpaper replacement, carpet replacement, or furniture movement. When the relationship between the illumination intensity on the illuminated surface and the output of the illumination sensor 3 changes, an appropriate illumination intensity on the illuminated surface cannot be obtained. For this reason, in the said conventional illumination control apparatus 1, in order to obtain appropriate illuminated surface illumination, it was necessary to reset the target value every time the layout was changed, and there was a problem that it took time and effort.

  As a lighting control device 1 that solves the above problem, as shown in FIG. 5, a control unit that compares the output of the illuminance sensor 3 with a target value and generates a control signal so that the output of the illuminance sensor 3 approaches the target value. 11, a transmission unit 12 that outputs a control signal that is controlled by the control unit 11 and is generated by the control unit 11, and a storage unit 13 that includes a rewritable memory such as an EEPROM. For example, see Patent Document 2). The illuminance sensor 3 outputs, for example, an illuminance signal that is a DC signal having a voltage value corresponding to the detected illuminance, and the voltage of the illuminance signal of the illuminance sensor 3 is between the control unit 11 and the illuminance sensor 3. An amplifying unit 14 for amplifying the value is inserted. In this case, “output of the illuminance sensor 3” refers to the voltage value of the illuminance signal amplified by the amplifying unit 14.

  In the illumination control device 1, the control unit 11 periodically obtained a calculation value obtained by dividing the output of the illuminance sensor by the dimming ratio while the light source was turned on (for example, every 10 minutes). The minimum calculated value that is the smallest of the calculated values is stored in the storage unit 13. Specifically, when the calculated value is obtained, the control unit 11 is the first calculated value after the power is turned on, or the calculated value newly obtained from the calculated value stored in the storage unit 13. When the calculated value is smaller, the obtained calculated value is stored in the storage unit 13 as the minimum calculated value. If the minimum calculated value stored in the storage unit 13 is smaller than the newly obtained calculated value, a new value is obtained. Discard the calculated value. That is, the control unit 11 is also a calculation unit.

  In addition, when the power is turned on, the control unit 11 sets a predetermined reference adjustment to a minimum calculated value within a period from when the power is last turned on to when the power is turned off (hereinafter referred to as “lighting period”). The product of the light ratio is used as a new target value. This is because if the lighting period includes the nighttime when there is no external light ED, the calculated value takes the minimum value at that time, so it is estimated that the minimum calculated value was obtained at night without the external light ED. To do. In the state where there is no reflected light ER caused by the external light ED and only the reflected light IR caused by the light ID of the light source is detected by the illuminance sensor 3, the output of the illuminance sensor 3 may be regarded as being directly proportional to the dimming ratio. The proportional coefficient is a value obtained by dividing the output of the illuminance sensor 3 by the dimming ratio, that is, the minimum calculated value. In other words, the illuminance sensor 3 when the desired illuminated surface illuminance can be obtained by multiplying the minimum calculated value by the reference dimming ratio, which is the dimming ratio capable of obtaining the desired illuminated surface illuminance under the condition that there is no external light ED. The above-mentioned conventional example uses this as a target value. The reference dimming ratio is, for example, 70%.

  According to the above configuration, even when the layout is changed, an appropriate target value is automatically set according to the layout change every time the power is turned on without having to re-enter the target value. Is done.

In addition, as shown in FIG. 6, there may be a case where a plurality of illuminance sensors 3 are provided in each illumination device 2 at positions where the light IDs of the light sources are not directly incident, and in this case, a plurality of illuminance sensors 3 are used. The average value or median value of the outputs is used as the output of the illuminance sensor 3 in the above description of the operation, or each light source is controlled individually using only the output of the illuminance sensor 3 provided in the same lighting device 2 as the light source. I will be broken.
JP-A-11-185974 JP 2006-40731 A

  However, in the above-described conventional configuration, when the external light ED is present when the minimum calculated value is obtained in the previous lighting period, if the external light ED is reduced to some extent as compared with that time, for example, more than 100%. A control signal that indicates a large dimming ratio may be output, causing malfunction.

  The present invention has been made in view of the above reasons, and an object of the present invention is to provide an illumination control device that can cope with a layout change but can suppress the occurrence of malfunction.

  The present invention is connected to at least one illuminating device that turns on each light source and an illuminance sensor that detects illuminance by reflected light on an illuminated surface illuminated by the light source, and dimming the light source for each illuminating device. An illumination control device that outputs a control signal instructing control, wherein a calculation unit that periodically calculates a calculation value obtained by dividing the output of an illuminance sensor by a dimming ratio, and a calculation value obtained by calculation of the calculation unit A storage unit that stores the minimum calculation value, which is the minimum value since the power is turned on, and a minimum calculation value that is stored in the storage unit when the power is turned off and then turned on When the minimum calculated value is lower than the nighttime determination threshold, the output of the illuminance sensor is brought close to the target value with a target value obtained by multiplying the minimum calculated value by a predetermined reference dimming ratio. To adjust the light source An external light tracking operation that outputs a control signal for instructing control to each lighting device is performed until the power is turned off, and the minimum calculated value is not stored in the storage unit when the minimum calculated value is higher than the nighttime determination threshold And a controller that performs an external light ignoring operation for outputting a control signal not related to the output of the illuminance sensor to each lighting device until the power is turned off.

  According to the present invention, the target value used in the external light follow-up operation is determined according to the minimum calculation value that changes according to the layout, so that it is possible to cope with the layout change. In addition, when the minimum calculated value is higher than the nighttime judgment threshold, that is, when it is considered that there is external light when the minimum calculated value is obtained, the external light ignoring operation regardless of the output of the illuminance sensor is performed. Therefore, the occurrence of malfunction due to the target value being set too high is suppressed.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  A block diagram of this embodiment is shown in FIG. Since the basic configuration of this embodiment is the same as that of the conventional example, common portions are denoted by the same reference numerals and description thereof is omitted.

  The control unit 11 according to the present embodiment compares the minimum calculated value stored in the storage unit 13 with a predetermined nighttime determination threshold value, so that whether or not the minimum calculated value is measured is a night when there is no external light ED. The operation until the power is turned off is determined according to the determination result. That is, when the minimum calculated value is equal to or less than the nighttime determination threshold, it is determined that the external light ED did not exist when the minimum calculated value was measured (that is, the night when the minimum calculated value was measured). In the same manner as described above, the target value is set to a value obtained by multiplying the minimum calculated value by a predetermined reference dimming ratio, so that the target value is made to correspond to the layout change and the output of the illuminance sensor 3 is brought close to this target value. The external light tracking operation is generated. If the minimum calculated value is larger than the nighttime determination threshold, it is determined that the external light ED was present when measuring the minimum calculated value (that is, it was not nighttime when measuring the minimum calculated value). An external light ignoring operation for generating a control signal not related to the output of the sensor 3 is performed.

  By the way, according to the experiment of the present inventor, when the indoor surface is covered with a white curing sheet used at the time of construction such as wiring work, when the state where the reflectance of the illuminated surface is as high as possible can be assumed, The output of the sensor 3 was about twice the average state.

  That is, the output of the illuminance sensor 3 with respect to the same light ID fluctuates more than twice due to the layout change, that is, the latest minimum calculated value becomes more than twice the previous minimum calculated value. If the latest minimum calculated value is obtained in the absence of external light ED, it is difficult to think. If the minimum calculated value fluctuates more than twice, the latest minimum calculated value is external light ED. It is thought that it was obtained in the state.

  Therefore, in the present embodiment, the storage unit 13 stores the minimum calculated value for the past two times from the newest one, and the control unit 11 sets twice the minimum calculated value obtained during the previous lighting period at night. Used as a determination threshold. The control unit 11 always performs the external light ignoring operation without performing the above determination when the minimum calculated values for the past two times are not stored in the storage unit, that is, at the first and second lighting.

  Here, in general, the luminous flux of the light source gradually decreases in accordance with the cumulative lighting time. For example, in the case of a fluorescent lamp, as shown in FIG. Therefore, in order to obtain a stable illuminated surface illuminance regardless of the accumulated lighting time at least during the operation of ignoring outside light, the present embodiment includes a lighting time measuring unit 15 that measures the cumulative lighting time of the light source of each lighting fixture 1. . Further, the control unit 11 includes an operation unit 16 that receives an operation input by a user, and the control unit 11 accumulates the light sources when a predetermined operation input indicating that the light source has been replaced in the lighting fixture 1 is received by the operation unit 16. Return the lighting time to 0 (reset). As the cumulative lighting time elapses during the external light ignoring operation, the controller 11 gradually increases the dimming ratio as shown in FIG. The light output is kept substantially constant regardless of the cumulative lighting time.

  According to the above configuration, the target value used in the external light follow-up operation is determined according to the minimum calculation value that changes according to the layout, so that it is possible to cope with the layout change. Further, when there is a high possibility that the external light ED was present when the minimum calculated value was obtained, an external light ignoring operation is performed in which the output of the illuminance sensor 3 is not used for generating a control signal. Occurrence of malfunction due to the output of the control signal instructing is suppressed.

  In the above embodiment, the control unit 11 generates the control signal according to the cumulative lighting time only during the external light ignoring operation. However, the control unit 11 performs the reference adjustment when calculating the target value used during the external light tracking operation. The cumulative lighting time may be reflected in the dimming ratio during the external light tracking operation by gradually increasing the light ratio in the same manner as the dimming ratio during the external light ignoring operation.

  Further, the nighttime determination threshold is not limited to the above. For example, the external light ED is blocked at the time of construction, and the calculated value is the highest as much as possible (for example, the distance between the illuminance sensor 3 and the illuminated surface). Is as short as possible and the reflectance of the illuminated surface is as high as possible), and the calculated value obtained in this state is stored in the storage unit as the nighttime determination threshold value. May be. That is, it is considered that the external light ED exists when a calculated value higher than the highest calculated value can be assumed as long as the external light ED is blocked.

It is a block diagram which shows the structure of embodiment of this invention. It is explanatory drawing which shows an example of the light beam decline accompanying progress of the accumulation lighting time of a light source. It is explanatory drawing which shows an example of the light control ratio which supplements the light beam decline of FIG. It is explanatory drawing which shows the usage condition of an illumination control apparatus. It is a block diagram which shows the structure of the conventional illumination control apparatus. It is explanatory drawing which shows another example of the usage pattern of an illumination control apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Illumination control apparatus 2 Illumination apparatus 3 Illuminance sensor 11 Control part 12 Transmission part 13 Storage part

Claims (1)

Each is connected to at least one illuminating device that turns on the light source and an illuminance sensor that detects illuminance by reflected light on the illuminated surface illuminated by the light source, and instructs each illuminating device to perform dimming control of the light source. A lighting control device that outputs a control signal,
A calculation unit that periodically calculates a calculation value obtained by dividing the output of the illuminance sensor by the dimming ratio, and a minimum calculation value that is the minimum value after the power is turned on among the calculation values obtained by the calculation of the calculation unit A storage unit for storing
When the power is turned off and then turned on again, the minimum calculated value stored in the storage unit is compared with a predetermined nighttime determination threshold, and if the minimum calculated value is lower than the nighttime determination threshold, the minimum External light tracking operation that outputs a control signal that directs the dimming control of the light source to each illumination device so that the output of the illuminance sensor approaches the target value with the value obtained by multiplying the calculated value by a predetermined reference dimming ratio as the target value Until the power is turned off, control signals that are not related to the output of the illuminance sensor are output when the minimum calculated value is higher than the nighttime judgment threshold and when the minimum calculated value is not stored in the storage unit for the first time. And a controller that performs an external light ignoring operation to be output to each lighting device until the power is turned off.

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