JP6156743B2 - Lighting device - Google Patents

Description

  The present invention relates to a lighting device including a proximity sensor.

  In recent years, lighting devices including a proximity sensor that detects that a human hand or the like has approached have become widespread. According to such an illuminating device, the illuminating device can be turned on and off without touching the power switch of the illuminating device. It is convenient because the lighting device can be operated simply by bringing it close to the lighting device. However, a proximity sensor that detects the approach of a hand or the like radiates infrared rays and consumes electric power. Therefore, an illuminating device including the proximity sensor needs to be devised for power saving.

  Therefore, conventionally, a technique related to power saving of a lighting device including a proximity sensor has been proposed (see, for example, Patent Document 1). In the technique of Patent Literature 1, a detection period in which the proximity sensor emits infrared rays and detects reflected infrared rays reflected from an object, and a non-detection period in which the proximity sensor stops emitting infrared rays and does not detect reflected infrared rays. Repeat alternately. Then, assuming that the total of one detection period and the subsequent non-detection period is a period, when the reflected infrared ray is detected, the period is made shorter than when the reflected infrared ray is not detected. Thereby, at the time of the standby which does not detect reflected infrared rays, since a period is later than the time of detection which detected reflected infrared rays, power saving is achieved.

JP 2006-69474 A

  However, the technique disclosed in Patent Document 1 has a problem in that since the cycle in which the detection period is repeated fluctuates, the user's feeling of use with respect to the response of the proximity sensor changes according to the fluctuation in the cycle. In other words, when the detection period is repeated for a short period, the time from when the hand is brought close to the proximity sensor until the lighting device reacts is stochastically shortened, but when the detection period is repeated for a long period, the hand is brought close to the proximity sensor. The time from when the lighting device reacts to becomes probabilistically longer. Therefore, in the technique of Patent Document 1, the user feels that there is a variation in the time from when the hand approaches the proximity sensor until the lighting device reacts, and there is a problem that the feeling of use with respect to the lighting device is not stable. .

  Therefore, the present invention has been made in view of such points, and an object of the present invention is to provide an illuminating device that saves power without changing the user's feeling of use with respect to the response of the proximity sensor.

  In order to achieve the above object, an embodiment of an illumination device according to the present invention includes a light source, a detection signal that radiates an electromagnetic wave, detects a reflected electromagnetic wave reflected by an object, and indicates the detection of the reflected electromagnetic wave. And a control unit that controls lighting and extinction of the light source based on the detection signal, and the control unit further detects the electromagnetic wave emission and the reflected electromagnetic wave. When the period is the detection period, and the period when the proximity sensor stops emitting the electromagnetic wave and does not detect the reflected electromagnetic wave is set as the non-detection period, the total of the detection period and the non-detection period is set to a fixed time. In addition, the proximity period is repeated so that the detection period and the non-detection period are alternately repeated, and the length of the detection period changes according to the state related to the detection by the proximity sensor. To control the difference.

  Here, the control unit detects the detection signal from the proximity sensor when the maximum response time is a maximum time that can occur between the time when the proximity sensor detects the reflected electromagnetic wave and the time when the detection signal is output. The proximity sensor may be controlled so that the detection period ends with the maximum response time when no is output.

  Further, the control unit outputs the detection signal from the proximity sensor before the detection period reaches the maximum response time, and when the output detection signal is in a predetermined stable state, The proximity sensor may be controlled so as to end without waiting for the detection period to reach the maximum response time.

  In addition, when the detection signal is output from the proximity sensor before the detection period reaches the maximum response time, the control unit detects the detection until the detection signal reaches a predetermined stable state. The proximity sensor is controlled so that the period continues, and when the detection period reaches the maximum response time until the detection signal becomes the stable state, the detection period continues longer than the maximum response time. The proximity sensor may be controlled to do so.

  In addition, when one of the repeated detection periods is set as the first detection period, the control unit exceeds the first threshold value predetermined in the first detection period, and the first It may be determined that the proximity sensor has detected an object when a second threshold value that is larger than the first threshold value is exceeded in a second detection period following the detection period, and the lighting and extinguishing of the light source may be controlled.

  According to the lighting device according to the present invention, power saving can be achieved without changing the user's feeling of use for the response of the proximity sensor.

  Therefore, the practical value of the present invention is extremely high nowadays when a convenient lighting device including a proximity sensor that enables non-contact lighting and extinguishing operations has become widespread.

The figure which shows the external appearance of the illuminating device in embodiment of this invention. The block diagram which shows the structure of the illuminating device in the embodiment The figure which shows the output characteristic of the proximity sensor in the same embodiment The figure which shows the operation timing of the proximity sensor in the embodiment Timing chart explaining characteristic control by control unit in the embodiment The flowchart which shows operation | movement of the illuminating device in the embodiment Communication sequence diagram showing communication exchange between the components constituting the lighting device in the embodiment Timing chart for explaining characteristic control by the control unit of the lighting device in the modification of the embodiment The flowchart which shows operation | movement of the illuminating device in the modification. 9A is a flowchart showing details of step S42 in FIG. 9A. The flowchart which shows the detail of step S43 in FIG. 9A.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Each of the embodiments described below shows a preferred specific example of the present invention. The numerical values, shapes, materials, constituent elements, arrangement positions and connecting forms of the constituent elements, steps, order of steps, and the like shown in the following embodiments are merely examples, and are not intended to limit the present invention. In addition, among the constituent elements in the following embodiments, constituent elements that are not described in the independent claims indicating the highest concept of the present invention are described as optional constituent elements that constitute a more preferable embodiment.

  FIG. 1 is a diagram illustrating an appearance of a lighting device 10 according to the present embodiment. FIG. 2 is a block diagram showing a configuration of the illumination device 10 shown in FIG. This illuminating device 10 is an illuminating device that operates under power supply from a commercial AC power supply 20 and can be turned on and off in a non-contact manner. The power source 11, the light source 12, the control unit 13, and A proximity sensor 14 is provided.

  The power source 11 is a circuit that converts AC power from the commercial AC power source 20 into power in a form suitable for the light source 12, and supplies the converted power to the light source 12 under the control of the control unit 13. , Rectifier circuit, chopper circuit and the like. The power supply 11 also generates operating voltages for the control unit 13 and the proximity sensor 14 and supplies them to each.

  The light source 12 is a light emitting unit that emits light, and is, for example, an LED (Light Emitting Diode), an organic EL (Electro-Liminence) element, a fluorescent lamp, or an incandescent lamp.

  The proximity sensor 14 is a sensor that detects that an object is approaching. The proximity sensor 14 radiates an electromagnetic wave, detects a reflected electromagnetic wave reflected by the object, and outputs a detection signal indicating detection of the reflected electromagnetic wave. It is an example. In the present embodiment, the proximity sensor 14 emits infrared rays as electromagnetic waves and detects reflected infrared rays as reflected electromagnetic waves. For this purpose, the proximity sensor 14 is a light emitting element that emits infrared light, a light receiving element that detects reflected infrared light, and causes the light emitting element to emit light in accordance with an instruction from the control unit 13 and outputs a signal from the light receiving element to the control unit 13. A control circuit is provided. The detection signal is a signal having characteristics as shown in FIG. 3, for example. FIG. 3 is a diagram showing the output characteristics of the proximity sensor 14. Here, a signal (pulse) having a wave height of about 5 to 1 V with respect to a detection distance of about 0 to 50 cm (a distance from the object to the proximity sensor 14). An example in which a signal is output is shown.

  More specifically, the proximity sensor 14 operates as shown in FIG. FIG. 4 is a diagram illustrating the operation timing of the proximity sensor 14. When the proximity sensor 14 receives a signal (“detection instruction signal” in FIG. 4A) instructing to detect reflected infrared rays by emitting infrared rays, the proximity sensor 14 is pulse-like (intermittent). It repeats emitting infrared rays ((b) of FIG. 4). For example, during the period when the detection instruction signal is High, the proximity sensor 14 emits infrared rays at an on-duty ratio of about 17% at a repetition frequency of 500 Hz (period 2 ms) and detects reflected infrared rays. When an object is detected, the proximity sensor 14 generates a detection signal and outputs it to the control unit 13 within the maximum response time (40 ms in this case), as shown in FIG. To do. Here, the “maximum response time” is the maximum time that can occur with respect to the time (response time) from when the proximity sensor 14 detects reflected electromagnetic waves (here, reflected infrared rays) until the detection signal is output to the control unit 13. It is. The proximity sensor 14 has a width (20 to 40 ms) as a response time in order to generate a detection signal by integrating a signal from a light receiving element that receives reflected infrared rays in synchronization with an internal timing circuit.

  The proximity sensor 14 is not limited to a sensor using infrared rays, and may be a sensor using electromagnetic waves. For example, the proximity sensor 14 may be a distance measuring sensor that detects a distance using radio waves such as microwaves.

  The control unit 13 is a circuit that controls the proximity sensor 14 and controls the power source 11 based on the detection signal from the proximity sensor 14 to turn on and off the light source. The processor 13a, D / A conversion A comparator 13b and a comparator 13c. The D / A converter 13b is a digital / analog converter that generates an analog voltage in accordance with an instruction (digital signal) from the processor 13a. The comparator 13c is a comparator that uses the analog voltage from the D / A converter 13b as a threshold, determines whether the detection signal from the proximity sensor 14 exceeds the threshold, and outputs the result to the processor 13a. The processor 13a is a one-chip microcomputer incorporating a control program, a timer, and the like, and controls the proximity sensor 14 and the power source 11 based on a signal from the comparator 13c, and controls the D / A converter 13b. To do.

  The control unit 13 performs the following characteristic operation. FIG. 5 is a timing chart for explaining characteristic control by the control unit 13. Here, as shown in FIG. 5, a period in which the proximity sensor 14 detects infrared radiation and reflected infrared light is called a detection period, and the proximity sensor 14 stops infrared radiation and does not detect reflected infrared light. Is called a non-detection period. FIG. 5 shows the timing when the proximity sensor 14 does not detect the reflected infrared light ((a) in FIG. 5) and when the proximity sensor 14 detects the reflected infrared light ((b) and (c) in FIG. 5). The figure is shown. FIG. 5B is a timing diagram when the proximity sensor 14 detects reflected infrared rays at a timing sufficiently earlier than the normal detection period (maximum response time). FIG. 5C is a timing diagram when the proximity sensor 14 detects reflected infrared rays immediately before the end of the normal detection period (maximum response time). 5A to 5C, the timing diagram arranged at the upper side shows the timing of the detection instruction signal transmitted from the control unit 13 to the proximity sensor 14, and the timing diagram arranged at the lower side is shown in FIG. The waveform of the detection signal output to the control part 13 from the proximity sensor 14 is shown.

  As a first feature, the control unit 13 sets the total (period) of the detection period and the non-detection period to a fixed time, and then repeats the detection period and the non-detection period, and the detection by the proximity sensor 14 The proximity sensor 14 is controlled so that the length of the detection period changes in accordance with the state regarding. As shown in FIGS. 5A to 5C, the detection period and the non-detection period are alternately repeated, and an interval (one detection cycle) consisting of one detection period and the subsequent non-detection period. The time (cycle) is always constant (here, 250 ms). However, the length of the detection period in one detection cycle varies depending on the state of detection by the proximity sensor 14. Due to such a feature, the detection period and the non-detection period are alternately repeated, so that power saving can be achieved as compared with the case where only the detection period continues. In addition, since the period in which the detection period is repeated is constant regardless of whether the proximity sensor 14 detects an object, the time from when the user brings an object such as a hand close to the proximity sensor 14 until the lighting device 10 reacts. The variation about is suppressed. That is, in any state (detection state of the proximity sensor 14), it is avoided that the user's feeling of use for the response of the proximity sensor 14 changes.

  As a second feature, as shown in FIG. 5A, the control unit 13 causes the proximity sensor 14 to end the detection period with the maximum response time when no detection signal is output from the proximity sensor 14. To control. That is, the normal (standby) detection period is set to the maximum response time. With such a feature, whether or not an object has approached the proximity sensor 14 is reliably determined every cycle.

  The third feature is the operation shown in FIG. When the detection signal is output from the proximity sensor 14 and the detection signal is in a predetermined stable state before the detection period reaches the maximum response time, the control unit 13 reaches the maximum response time. The proximity sensor 14 is controlled so as to end without waiting. In FIG. 5B, the detection period ends in a shorter period than in FIG. With such a feature, it is avoided that unnecessary infrared radiation continues in spite of detection of reflected infrared rays by the proximity sensor 14 in one detection cycle, and further power saving is achieved. The “predetermined stable state” is a state of a detection signal indicating that the proximity sensor 14 has reliably detected an object. In other words, a state in which a valid detection signal is output from the proximity sensor 14. is there. Here, when the wave height of the detection signal exceeds a predetermined threshold value (voltage), it is determined that the detection signal is in a “predetermined stable state”.

  The fourth feature is the operation shown in FIG. When the detection signal is output from the proximity sensor 14 until the detection period reaches the maximum response time, the control unit 13 approaches so that the detection period continues until the detection signal reaches a predetermined stable state. The sensor 14 is controlled. That is, when the detection signal from the proximity sensor 14 rises but the detection period reaches the maximum response time until the detection signal becomes stable, the control unit 13 continues the detection period longer than the maximum response time. Thus, the proximity sensor 14 is controlled. In FIG. 5C, the detection period continues longer than in FIG. 5A. As a result, even if the reflected infrared rays are detected immediately before the end of the normal detection period, the detection period is extended until a complete detection signal is generated. Is avoided, and a faster reaction (detection process) is realized.

  Next, operation | movement of the illuminating device 10 in this Embodiment comprised as mentioned above is demonstrated. FIG. 6 is a flowchart showing the operation of the illumination device 10 in the present embodiment.

  First, the control unit 13 transmits a detection instruction signal (High level) to the proximity sensor 14 to turn on detection of infrared radiation and reflected infrared radiation by the proximity sensor 14 (S10). Thereby, the detection period is started.

  Subsequently, the control unit 13 determines whether or not the detection signal output from the proximity sensor 14 has risen (S11). Specifically, the control unit 13 determines whether or not the detection signal output from the proximity sensor 14 exceeds a predetermined threshold value. Here, the “predetermined threshold value” is a threshold value for detecting that the detection signal has risen, and is a voltage slightly higher than the noise level of the detection signal. It is set to a voltage that is the same as or lower than the threshold value for determining “stable state”. More specifically, in this step, the D / A converter 13b that has received a predetermined threshold value instruction (digital value) from the processor 13a in the control unit 13 converts the digital value into an analog voltage, and the comparator To 13c. The comparator 13c compares the analog voltage with the detection signal output from the proximity sensor 14, and outputs a signal indicating that to the processor 13a when the detection signal exceeds the analog voltage. Thereby, the processor 13a determines whether or not the detection signal exceeds a predetermined threshold value.

  As a result, when it is determined that the detection signal has not risen (No in S11), the controller 13 determines that the elapsed time after the proximity sensor 14 is turned on (S10) (that is, the detection period) is the maximum response time. Is determined (S12). Specifically, in the control unit 13, the processor 13a determines whether or not the value of the built-in timer started when the proximity sensor 14 is turned on exceeds the maximum response time (for example, 45 ms or more). to decide. As a result, when the detection period has not reached the maximum response time (No in S12), the control unit 13 determines again the rise of the detection signal (S11). On the other hand, when the detection period has reached the maximum response time (Yes in S12), the control unit 13 turns off the proximity sensor 14 (S15). Thereby, when a detection signal is not output from the proximity sensor 14 (during standby), the detection period ends with the maximum response time (see FIG. 5A).

  On the other hand, when it is determined that the detection signal has risen (Yes in S11), the control unit 13 confirms whether or not the rised detection signal has reached a predetermined stable state (S13). Specifically, the control unit 13 determines whether or not the detection signal has exceeded a predetermined threshold value (≧ threshold value for determining the rising edge) for confirming that the detection signal has reached a predetermined stable state. Judging. More specifically, an instruction (digital value) corresponding to a predetermined threshold value for confirming that a predetermined stable state has been reached is output from the processor 13a to the D / A converter 13b for D / A conversion. The analog voltage converted by the comparator 13b is output to the comparator 13c. Then, the comparator 13c compares the analog voltage with the detection signal and outputs the comparison result to the processor 13a. Thus, the processor 13a determines whether or not the detection signal has reached a predetermined stable state by determining whether or not the detection signal exceeds a predetermined threshold value.

  As a result, when it is determined that the detection signal has not reached a predetermined stable state (No in S13), the control unit 13 determines that the detection signal is not a valid detection signal, and returns to the original process. Then, the detection period is determined (S12). On the other hand, when it is determined that the detection signal is in a predetermined stable state (Yes in S13), the control unit 13 controls the power source 11 to turn on / off the light source 12 (the light source 12 is turned off). If it is lit, it is turned on, and if it is lit, it is turned off) (S14).

  Subsequently, the control unit 13 terminates the detection instruction signal (High) output to the proximity sensor 14 (sets it to the Low level), thereby stopping the infrared radiation by the proximity sensor 14 and detecting the reflected infrared light. Turn off (S15). As a result, the detection period ends and the non-detection period starts.

  As described above, when the detection signal that has risen becomes a predetermined stable state (S13), after the light source 12 is turned on / off (S14), the detection period ends without depending on the elapsed time. (S15). Therefore, in such a case, depending on the timing at which the detection signal rises, the detection period may end before reaching the maximum response time (see FIG. 5B), or the detection period is the maximum response time. May be terminated (see (c) of FIG. 5). Thereby, when the detection period ends before reaching the maximum response time, power saving is achieved. On the other hand, when the detection period ends beyond the maximum response time, the detection process in the control unit 13 is performed. Is prevented from being rotated in the next cycle, and a faster reaction (detection process) is realized.

  Finally, the control unit 13 determines whether or not the elapsed time since the proximity sensor 14 is turned on (S10) (that is, the sum of the detection period and the non-detection period) has reached a predetermined period. Judgment is made (S16). Specifically, in the control unit 13, the processor 13a determines whether or not the value of the built-in timer started when the proximity sensor 14 is turned on has reached a certain period (for example, 250 ms or more). to decide. As a result, when the elapsed time does not reach a certain period (No in S16), the control unit 13 repeats the determination (S16), and when the elapsed time reaches a certain period (S16). Yes), the above-described series of processing is repeated again (S11 to S16).

  FIG. 7 is a communication sequence diagram illustrating an example of communication exchange between the components constituting the illumination device 10 according to the present embodiment.

  In response to the detection instruction signal (High) from the control unit 13 (S20), the proximity sensor 14 turns on infrared radiation (detection period starts) (S21). Here, since the detection signal is not output from the proximity sensor 14 until the maximum response time elapses after the start of the detection period, the proximity sensor 14 from the control unit 13 when the maximum response time elapses. The detection instruction signal (Low) is input to (S22). Thereby, in the proximity sensor 14, infrared radiation is turned off (the detection period ends, that is, the non-detection period starts) (S23). The time from when the detection instruction signal (High) is input until the infrared radiation is turned on, and the time from when the detection instruction signal (Low) is input until the infrared radiation is turned off are as follows. Compared with the detection period and the non-detection period, the period is negligibly short. Accordingly, the timing at which the detection instruction signal (High) is input and the infrared radiation is turned on, and the timing at which the detection instruction signal (Low) is input and the infrared radiation is turned off can be regarded as simultaneous.

  Subsequently, when a certain period has elapsed since the immediately preceding detection period started (S21), the detection period is started in the proximity sensor 14 again by a detection instruction signal (High) from the control unit 13 (S24). (S25). Thereafter, by the time the maximum response time elapses after the start of the detection period, an object such as a hand approaches the proximity sensor 14, and a detection signal from the proximity sensor 14 rises (S26). The control unit 13 determines that the detection signal has reached a predetermined stable state, and the control unit 13 controls the power source 11 (S27). As a result, the light source 12 is turned on / off (S28). . Subsequently, the detection instruction signal transmitted from the control unit 13 to the proximity sensor 14 becomes Low (S29), and the detection period ends (the non-detection period starts) (S30).

  Thereafter, when a certain period has elapsed since the immediately preceding detection period started (S25), the detection period is started in the proximity sensor 14 again by a detection instruction signal (High) from the control unit 13 (S31). (S32).

  As described above, according to the illumination device 10 of the present embodiment, the total (period) of the detection period and the non-detection period in the proximity sensor 14 is set to a certain time by the control based on the detection instruction signal from the control unit 13. In addition, the detection period and the non-detection period are alternately repeated. Thereby, power saving can be achieved compared with the case where only the detection period continues. And although the length of a detection period changes according to the state regarding the detection by the proximity sensor 14, the period in which a detection period is repeated is constant. Therefore, variation in the time from when the user brings an object such as a hand close to the proximity sensor 14 until the lighting device 10 reacts is suppressed, and the proximity sensor 14 is in any state (detection state of the proximity sensor 14). The user's feeling of use in response to this response will not change. That is, the reaction speed of the proximity sensor 14 is always constant.

  Further, when the detection signal is not output from the proximity sensor 14 (standby), the detection period ends with the maximum response time, so whether or not the object has approached the proximity sensor 14 is ensured every cycle. Is determined.

  In addition, when the detection signal is output from the proximity sensor 14 until the detection period reaches the maximum response time, and the output detection signal reaches a predetermined stable state, the detection period reaches the maximum response time. Exit without waiting. Thereby, in one detection cycle, it is avoided that unnecessary infrared radiation continues even though the proximity sensor 14 detects reflected infrared rays, and further power saving is achieved. That is, when the present invention is not used, the detection period is the sum of the maximum response time and the stable time (the time from when the detection signal is output until the stable state is reached). The time is shorter and power saving is achieved. At the same time, useless infrared radiation is suppressed for the proximity sensor 14, and the life of the light emitting element that emits infrared radiation is extended.

  Further, when the detection signal is output from the proximity sensor 14 until the detection period reaches the maximum response time, the proximity sensor 14 is set so that the detection period continues until the detection signal reaches a predetermined stable state. Be controlled. That is, when the detection signal reaches the maximum response time until the detection signal from the proximity sensor 14 rises and becomes stable, the detection period is extended to be longer than the maximum response time. As a result, even if the reflected infrared rays are detected immediately before the end of the normal detection period, the detection period is extended until a complete detection signal is generated. Is avoided, and a faster reaction (detection process) is realized.

  In the above embodiment, the threshold used for determining whether or not the detection signal is output effectively, that is, the threshold for confirming that the detection signal is in a predetermined stable state is the detection cycle. It was constant without depending on. However, this threshold may be varied depending on the detection cycle. Hereinafter, an embodiment in which the threshold value used for determining whether or not the detection signal is output effectively will be described as a modification of the above embodiment. Note that this modification is basically realized by the same components as those in the above embodiment. However, the function of the control unit 13 (strictly speaking, the processor 13a) included in the illumination device 10 is different between the above embodiment and the present modification. Hereinafter, different points will be mainly described.

  FIG. 8 is a timing diagram illustrating characteristic control by the control unit 13 of the lighting apparatus 10 in the present modification, and corresponds to FIG. 5 in the above embodiment. FIG. 8 shows timing charts when the proximity sensor 14 does not detect the reflected infrared ray (FIG. 8A) and when the proximity sensor 14 detects the reflected infrared ray (FIG. 8B). ing. 8A and 8B, the timing diagram arranged at the upper side shows the timing of the detection instruction signal transmitted from the control unit 13 to the proximity sensor 14, and the timing diagram arranged at the lower side is shown in FIG. The waveform of the detection signal output to the control part 13 from the proximity sensor 14 is shown.

  Here, the control unit 13 sets a low value (for example, lower than a value set by the user) as an initial value of a threshold value (a threshold value during standby) for confirming that the detection signal is in a predetermined stable state. Value). That is, during standby, the control unit 13 monitors with high sensitivity whether or not a valid detection signal is output from the proximity sensor 14 using a threshold value set to a low value ((a) in FIG. 8). . And when the detection signal exceeding such a low value is detected, the control part 13 changes a threshold value into a higher value (for example, the value which the user set) in the next detection period. Then, the control unit monitors whether or not a valid detection signal is output from the proximity sensor 14 (with normal sensitivity) using the changed threshold value (threshold value set to a high value) ((b in FIG. 8). ) Later detection period). When the detection signal exceeds the low threshold and the high threshold continuously (in successive detection cycles), the control unit 13 determines that a valid detection signal has been output, and turns on / off the light source 12.

  As described above, when one of the repeated detection periods is set as the first detection period, the control unit 13 exceeds the first threshold value predetermined in the first detection period, and the first detection period. When the second threshold value larger than the first threshold value is exceeded in the second detection period that follows, it is determined that the proximity sensor 14 has detected an object, and the light source 12 is turned on and off. Thereby, it is possible to detect a detection signal with high sensitivity and to prevent chattering in detection of the detection signal. Moreover, since the threshold value used for the first detection of the detection signal is a value lower than the normal set value, there is a high possibility that an effective detection signal is detected at a timing earlier than the normal detection. Therefore, there is a possibility that the detection period ends shortly (see FIG. 5B), and power saving can be achieved. At the same time, for the proximity sensor 14, the emission of infrared rays is suppressed by the amount corresponding to the shortened detection period, and the lifetime of the light emitting element that emits infrared rays is extended.

  FIG. 9A is a flowchart showing the operation of the illumination device 10 in the present modification.

  First, the control unit 13 manages a flag for managing whether the detection signal should be detected with high sensitivity (Flag = 0) or whether the detection signal should be detected with normal sensitivity (Flag = 1). The Flag is initialized (the flag Flag is set to “0”) (S40). The flag Flag is a variable temporarily stored in the internal memory of the processor 13a.

  Subsequently, the control unit 13 determines whether or not the value of the flag Flag is set to “1” (S41). As a result, when the value of the flag Flag is not “1” (No in S41), the control unit 13 monitors whether or not the detection signal from the proximity sensor 14 is effectively output with high sensitivity ( S42).

  The details of step S42 (monitoring of the detection signal with high sensitivity) are as shown in the flowchart of FIG. 9B. The flowchart in FIG. 9B is different from the flowchart in FIG. 6 in that step S50 is inserted immediately before step S13, step S51 is executed instead of step S14, and the process returns from step S16 to step S10. The only difference is that there is no flow. The same steps as those in FIG. 6 are denoted by the same reference numerals as those in FIG. Here, when detecting the rising edge of the detection signal (Yes in S11), the control unit 13 sets a low threshold value (for example, the user sets a threshold value for confirming that the detection signal is in a predetermined stable state). A value lower than the value) is set (S50). Then, the control unit 13 uses the threshold value set to a low value to determine whether or not the detection signal has reached a predetermined stable state, that is, whether or not a valid detection signal is output from the proximity sensor 14. Monitor by sensitivity (S13). When it is determined that the detection signal has reached a predetermined stable state (Yes in S13), the control unit 13 sets the flag Flag to “1” (S14). Other processes are the same as those in the flowchart of FIG. Thus, in the monitoring of the detection signal with high sensitivity (S42, FIG. 9B), the flag Flag is set to “1” when a valid detection signal is detected, and the flag Flag is set otherwise. It remains “0”.

  Thereafter, referring to FIG. 9A again, the flag Flag is determined again (S41). Here, if a valid detection signal is detected in the monitoring of the detection signal with high sensitivity in the immediately preceding detection period (S42), the flag Flag is set to “1”. Determines that the value of the flag Flag is “1” (Yes in S41). As a result, in the subsequent detection period, the control unit 13 monitors whether the detection signal from the proximity sensor 14 has been effectively output with normal sensitivity (S43).

  Details of step S43 are as shown in the flowchart of FIG. 9C. The flowchart of FIG. 9C is different from the flowchart of FIG. 6 in that step S55 is inserted immediately before step S13, there is no flow from step S16 to step S10, and step S56 is inserted after step S16. Only the differences are different. The same steps as those in FIG. 6 are denoted by the same reference numerals as those in FIG. Here, when the rising of the detection signal is detected (Yes in S11), the control unit 13 sets a higher threshold value (for example, set by the user) for confirming that the detection signal is in a predetermined stable state. (S55). Then, the control unit 13 normally uses the threshold value set to a high value to determine whether or not the detection signal has reached a predetermined stable state, that is, whether or not a valid detection signal has been output from the proximity sensor 14. Monitor by sensitivity (S13). When it is determined that the detection signal has reached a predetermined stable state (Yes in S13), the control unit 13 controls the power supply 11 to turn on / off the light source 12 (the light source 12 was off). In this case, it is turned on, and if it is turned on, it is turned off) (S14). Then, as the last process here (after step S16), the control unit 13 returns the flag Flag to “0” (S56). Other processes are the same as those in the flowchart of FIG. As described above, in the monitoring of the detection signal with the normal sensitivity during this detection period (S43, FIG. 9C), the light source 12 is turned on / off only when a valid detection signal is detected (S14). Finally, the flag Flag is always returned to “0” regardless of whether a valid detection signal is detected (S56).

  Thereafter, referring to FIG. 9A again, the determination of flag Flag (S41) and the processing (S42 / S43) corresponding to the result are repeated. Due to such a flow, an effective detection signal is output from the proximity sensor 14 only when a detection signal is detected at a low threshold and a detection signal is detected at a higher threshold in the detection period following the detection period. The light source 12 is turned on / off.

  As described above, when one of the repeated detection periods is set as the first detection period, the control unit 13 exceeds the first threshold value predetermined in the first detection period, and the first detection period. When the second threshold value larger than the first threshold value is exceeded in the second detection period that follows, it is determined that the proximity sensor 14 has detected an object, and the light source 12 is turned on and off. Thereby, it is possible to detect a detection signal with high sensitivity and to prevent chattering in detection of the detection signal. Moreover, since the threshold value used for the first detection of the detection signal is a value lower than the normal set value, there is a high possibility that an effective detection signal is detected at a timing earlier than the normal detection. Therefore, there is a possibility that the detection period ends shortly (see FIG. 5B), and power saving can be achieved.

  The lighting device according to the present invention has been described based on the embodiments and the modifications. However, the present invention is not limited to these embodiments and modifications. As long as it does not deviate from the gist of the present invention, various modifications conceived by those skilled in the art are applied to the present embodiment and modifications, and forms constructed by combining components in the embodiments and modifications are also included in the present invention. May be included.

  For example, in the above-described embodiment and modification, when the wave height of the detection signal exceeds a predetermined threshold value (voltage), it is determined that the detection signal has become a “predetermined stable state”. The determination method of “predetermined stable state” is not limited to this. After the detection signal rises, the detection signal becomes “predetermined stable state” when the wave height of the detection signal does not change for a certain time or longer (that is, the detection signal effective from the proximity sensor 14). May be determined).

  Moreover, in the said embodiment, although the control part 13 had four characteristics (1st-4th characteristics), it should just have at least one of four characteristics. Further, in the above modification, the deformation operation of the control unit 13 having the above four characteristics has been described. However, in this modification, the control unit 13 only needs to have at least one of the four characteristics.

  In the above embodiment, the proximity sensor 14 outputs an analog voltage as a detection signal. However, the proximity sensor 14 may output a digital value together with or instead of the output of the analog voltage. In this case, in the control unit 13, the digital value output from the proximity sensor 14 is input to the processor 13 a, and the processor 13 a compares the detection signal with various threshold values, so the D / A converter 13 b and the comparison The container 13c becomes unnecessary.

DESCRIPTION OF SYMBOLS 10 Illuminating device 11 Power supply 12 Light source 13 Control part 13a Processor 13b D / A converter 13c Comparator 14 Proximity sensor 20 Commercial alternating current power supply

Claims (5)

A light source;
A proximity sensor that radiates electromagnetic waves, detects the reflected electromagnetic waves reflected by the object, and outputs a detection signal indicating detection of the reflected electromagnetic waves;
A control unit that controls turning on and off of the light source based on the detection signal,
The control unit further detects a period in which the proximity sensor detects the emission of the electromagnetic wave and the reflected electromagnetic wave, and does not detect a period in which the proximity sensor stops the emission of the electromagnetic wave and does not detect the reflected electromagnetic wave. When the period is set, the detection period and the non-detection period are alternately repeated after the total of the detection period and the non-detection period is set to a fixed time, and the state related to the detection by the proximity sensor The illumination device that controls the proximity sensor so that the length of the detection period changes accordingly. The control unit outputs the detection signal from the proximity sensor when a maximum response time is defined as a maximum time that can occur from the time when the proximity sensor detects the reflected electromagnetic wave to the time when the detection signal is output. The lighting device according to claim 1, wherein the proximity sensor is controlled so that the detection period ends with the maximum response time when the lever is not picked up. The control unit outputs the detection signal from the proximity sensor before the detection period reaches the maximum response time, and when the output detection signal is in a predetermined stable state, the detection period The lighting device according to claim 2, wherein the proximity sensor is controlled so as to end without waiting for the maximum response time to be reached. In the case where the detection signal is output from the proximity sensor before the detection period reaches the maximum response time, the control unit determines that the detection period is increased until the detection signal becomes a predetermined stable state. The proximity sensor is controlled to continue, and when the detection period reaches the maximum response time until the detection signal becomes the stable state, the detection period continues longer than the maximum response time. The illumination device according to claim 2, wherein the proximity sensor is controlled. In the case where one of the repeated detection periods is set as a first detection period, the control unit exceeds a first threshold value predetermined in the first detection period, and the first detection period 2. The illumination according to claim 1, wherein the proximity sensor determines that an object has been detected when a second threshold value that is greater than the first threshold value is exceeded in a second detection period that follows, and controls lighting and extinction of the light source. apparatus.

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