Sterilization and deodorization machine, control program, and control method

Abstract

To provide a sterilization / deodorization machine which can efficiently perform sterilization / deodorization by recovering decomposition efficiency of an organic matter.SOLUTION: A sterilization / deodorization machine includes a housing 20 having a suction port 24 and an exhaust port 26, a filter unit 12 having a photocatalyst filter, a light source 14 for irradiating the photocatalyst filter with light, a blowing fan 16 for generating an air flow passing through a unit storage part, and a contamination sensor 36 between the photocatalyst filter and the blowing fan, wherein a control part drives the light source at a maximum light amount and drives the blowing fan low wind speed when determining that an excessive organic matter is attached to the photocatalyst filter on the basis of a detection value of the contamination sensor, and refreshes the photocatalyst filter.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a sterilizing deodorizer, a control program, and a control method, and more particularly to a sterilizing deodorizer, a control program, and a control method, which perform sterilization and deodorization using a photocatalytic filter carrying a photocatalyst. [Background technology]

[0002] An example of a conventional sterilizing deodorizer (photocatalytic device) is disclosed in Patent Document 1. The sterilizing deodorizer of Patent Document 1 comprises a housing, a filter unit (photocatalytic unit) including a photocatalytic filter (photocatalytic sheet) and disposed within the housing, a light source (light) for providing light to the photocatalytic filter, and a blower fan for blowing air over the surface of the photocatalytic filter. The filter unit is detachably mounted on the housing. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-37285 Summary of the Invention [Problem to be solved by the invention]

[0004] The technology of Patent Document 1 uses a flat photocatalytic filter, so in order to achieve sufficient organic matter decomposition performance (i.e., sterilization and deodorization performance), the photocatalytic filter must be made large, which creates the problem of making the device larger.

[0005] Therefore, a primary object of the present invention is to provide a novel sterilizing and deodorizing machine.

[0006] Another object of the present invention is to provide a sterilizing and deodorizing machine that can efficiently sterilize and deodorize and that can be made compact. [Means for solving the problem]

[0007] The first invention is a sterilizing deodorizer comprising a blower fan, a photocatalytic filter carrying a photocatalyst, a light source for irradiating the photocatalytic filter, and a first sensor arranged downstream of the photocatalytic filter in the direction of airflow by the blower fan and for detecting organic matter contained in the air, the first sensor comprising a control unit that causes the light source to emit light at a maximum light intensity that is the greatest of the light intensities emitted by the sterilizing deodorizer during operation, and drives the blower fan at a minimum wind speed that is the slowest of the wind speeds at which the sterilizing deodorizer blows air during operation, thereby refreshing the photocatalytic filter. The control unit executes a first confirmation process to confirm the amount of organic matter adhering to the photocatalytic filter from the difference between the detection values ​​detected by the first sensor when the light source is made to emit light at two different light intensities, and determines whether or not the photocatalytic filter needs to be refreshed based on the result of the first confirmation process. It is a sterilizing and deodorizing machine.

[0009] No. 2 The invention is 1 of According to the invention, the control unit, in the first confirmation process, calculates a first detection value of the first sensor when the light source is driven at a first light amount for a first predetermined time, and a second detection value of the first sensor when the light source is driven at a second light amount greater than the first light amount for the first predetermined time. No. 1 Detect the difference, No. 1 If the difference is smaller than the first determination value, the light source is caused to emit light at a maximum light amount greater than the second light amount, and the blower fan is driven at a minimum wind speed to refresh the photocatalytic filter.

[0010] No. 3 The invention is 1 or 2 The first confirmation process is executed when a detection value of the first sensor in a state where the light source is turned off is equal to or greater than a first predetermined value.

[0011] No. 4 The invention is 2 Departure Clearly The first difference is 2 or more 1 The control unit determines that the number of times the first difference is smaller than the first determination value is the first determination value. 2 When the detection is made a predetermined number of times, the photocatalytic filter is refreshed.

[0012] No. 5 The invention of a control unit that causes the light source to emit light at a maximum light intensity that is the highest light intensity that can be emitted by the sterilization deodorizer while it is operating, and drives the blower fan at a minimum wind speed that is the slowest wind speed that can be sent by the sterilization deodorizer while it is operating, thereby refreshing the photocatalytic filter; and a light source that irradiates the photocatalytic filter. A second sensor detects organic matter contained in the air upstream of the catalytic filter in the direction of airflow from the fan. Equipped with Well, the control unit is In a state where the blower fan is driven under the condition of a first predetermined wind speed, The detected value of the second sensor is greater than the second judgment value, Specified light intensity In front The light source is illuminated. and driving the blower fan under conditions that result in a second predetermined wind speed. a second confirmation process for confirming whether the photocatalytic filter is dirty from a second difference between the detection value of the second sensor and the detection value of the first sensor in a state where the photocatalytic filter is dirty; , a sterilizing and deodorizing machine .

[0013] No. 6 The invention is 5 The control unit is configured to: 3 If the measured value is smaller than the judgment value, the light source is caused to emit light at the maximum light intensity, the blower fan is driven at the minimum wind speed, and the photocatalytic filter is refreshed.

[0014] No. 7 The invention is 5 or 6 The second confirmation process is executed when the detection value of the first sensor or the second sensor in a state where the light source is turned off is equal to or greater than a first predetermined value.

[0015] The eighth invention is of 6 Departure Clearly The second difference is calculated a third predetermined number of times, which is two or more times, and the control unit refreshes the photocatalytic filter when the number of times the second difference is smaller than the third judgment value is detected a fourth predetermined number of times. [Effects of the Invention]

[0020] According to this invention, by refreshing the photocatalytic filter, organic matter adhering to the photocatalytic filter can be decomposed and the decomposition efficiency of the organic matter can be restored. Therefore, sterilization and deodorization can be performed efficiently. Furthermore, the photocatalytic filter can be refreshed at an appropriate timing.

[0021] The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description of the preferred embodiments, which proceeds with reference to the accompanying drawings. [Brief explanation of the drawings]

[0022] [Figure 1] FIG. 1 is a perspective view showing a sterilizing deodorizing machine according to a first embodiment of the present invention. [Figure 2] FIG. 2 is a vertical cross-sectional view showing the internal structure of the sterilizing deodorizing machine. [Figure 3] FIG. 3 is a cross-sectional view showing the internal structure of the sterilizing deodorizing machine. [Figure 4] FIG. 4 is a perspective view showing the filter unit. [Figure 5] FIG. 5 is a diagram showing the state when the filter unit is attached to the housing of the sterilizing deodorizing machine. [Figure 6] FIG. 6 is a diagram showing a schematic structure of a sterilizing and deodorizing machine. [Figure 7] FIG. 7 is a block diagram showing the electrical configuration of the sterilizing deodorizing machine. [Figure 8] FIG. 8 is a graph showing the change over time in the concentration of organic matter in the air when photocatalytic filters with different amounts of attached organic matter are used. [Figure 9] FIG. 9 is a table showing criteria for determining the degree of contamination. [Figure 10] FIG. 10 is a table showing information on operation control. [Figure 11] FIG. 11 is a diagram showing a memory map of the RAM shown in FIG. [Figure 12] FIG. 12 is a flowchart showing the filter contamination confirmation process of the CPU shown in FIG. [Figure 13] FIG. 13 is a flowchart showing the confirmation execution determination process of the CPU shown in FIG. [Figure 14] FIG. 14 is a diagram showing a schematic structure of the sterilizing deodorizing machine of the second embodiment. [Figure 15] FIG. 15 is a block diagram showing the electrical configuration of the sterilizing deodorizing machine of the second embodiment. [Figure 16] FIG. 16 is a flowchart showing the filter contamination checking process of the CPU of the sterilizing deodorizing machine of the second embodiment. [Figure 17] FIG. 17 is a flowchart showing the refresh control process of the CPU of the sterilizing deodorizing machine of the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0023] [First Example] 1 and 2, a sterilizing deodorizer 10 according to a first embodiment of the present invention is a device that performs sterilization and deodorization using a photocatalytic filter 40 that carries a photocatalyst. As will be described in detail below, the sterilizing deodorizer 10 performs sterilization and deodorization by causing air taken in from the outside to flow along the main surface (surface) of the photocatalytic filter 40 and irradiating the photocatalytic filter 40 with light, thereby decomposing organic matter (organic compounds) adhering to the photocatalytic filter 40. The configuration of the sterilizing deodorizer 10 will be specifically described below.

[0024] 1 to 3, the sterilizing deodorizing machine 10 includes a filter unit 12 including a photocatalytic filter 40 and a holding frame 42, a light source 14, a blower fan 16, an activated carbon filter 18, and a control unit 100 (see FIG. 7), which are housed in a housing 20 in a predetermined arrangement. The control unit 100 includes a CPU 102, memories (106, 108), and the like, and controls the operation of each part of the sterilizing deodorizing machine 10 (such as the light source 14 and the blower fan 16) based on input operations made to an operation unit 22 including a power button 22a, etc.

[0025] For example, when sterilizing and deodorizing, the sterilizing deodorizer 10 can operate in three operation modes (silent mode, normal mode, and strong mode in the first embodiment), and the control unit 100 switches the operation mode (hereinafter, for convenience of explanation, may be referred to as the "sterilizing and deodorizing operation mode") in response to a user's input operation. However, as for the sterilizing and deodorizing operation mode, silent mode is selected when the power is turned on, and normal mode or strong mode can be selected in response to a user's operation, and further, silent mode can be selected in normal mode or strong mode in response to a user's operation. Alternatively, the sterilizing and deodorizing operation mode may be set automatically.

[0026] As an example, when the sterilization and deodorization operation mode is silent (low) mode, light source 14 is driven at a duty ratio of 60%, and blower fan 16 is driven at a duty ratio of 25%. When the sterilization and deodorization operation mode is normal (medium) mode, light source 14 is driven at a duty ratio of 60%, and blower fan 16 is driven at a duty ratio of 75%. When the sterilization and deodorization operation mode is strong mode, light source 14 is driven at a duty ratio of 80%, and blower fan 16 is driven at a duty ratio of 100%.

[0027] However, the light source 14 is turned off at a duty ratio of 0% and emits the maximum light intensity at a duty ratio of 100%. The blower fan 16 is driven to achieve the minimum wind speed at a duty ratio of 25% or less (including 0%) and to achieve the maximum wind speed at a duty ratio of 100%. In this specification, for convenience, the greatest light intensity emitted by the sterilizing deodorizer 10 during operation may be referred to as the maximum light intensity. The slowest wind speed among the wind speeds blown by the sterilizing deodorizer 10 during operation may be referred to as the minimum wind speed.

[0028] The housing 20 is formed in a rectangular parallelepiped shape. An intake port 24 is provided at the bottom of the housing 20, and an exhaust port 26 is provided at the top of the housing 20. A unit housing section 28 is provided at the center of the housing 20. The filter unit 12 is housed (attached) in a vertical orientation in this unit housing section 28. The specific configuration of the filter unit 12 will be described later.

[0029] The light source 14 includes a substrate 30 and a plurality of LEDs (light emitting diodes) 32 distributed on the surface of the substrate 30, and is provided so as to face the main surface of the photocatalytic filter 40. In this embodiment, the light source 14 includes a first light source 14a provided so as to face one main surface of the photocatalytic filter 40, and a second light source 14b provided so as to face the other main surface of the photocatalytic filter 40. That is, the light sources 14 are provided on both sides in the thickness direction of the filter unit 12, and can irradiate light onto each of both main surfaces of the photocatalytic filter 40. Each of the first light source 14a and the second light source 14b is provided with, for example, 12 LEDs 32.

[0030] The blower fan 16 is provided at the top of the housing 20, i.e., between the exhaust port 26 and the unit housing section 28 (i.e., the filter unit 12), and generates an upward airflow (air current) from the intake port 24 through the unit housing section 28 toward the exhaust port 26. That is, air taken into the housing 20 from the intake port 24 by driving the blower fan 16 flows upward through the unit housing section 28 and is then discharged outside the housing 20 from the exhaust port 26. As the blower fan 16, a well-known fan such as an axial fan such as a propeller fan or a centrifugal fan may be used.

[0031] An activated carbon filter housing 34 is provided in the lower part of the housing 20, i.e., between the air intake 24 and the unit housing 28. The activated carbon filter 18 is housed in this activated carbon filter housing 34 in a horizontal position so as to cover the air intake 24. That is, the air taken into the housing 20 from the air intake 24 passes through the activated carbon filter 18 in the thickness direction (i.e., passes through the inside of the activated carbon filter 18) and then flows into the unit housing 28. The activated carbon filter 18 is a filter in which activated carbon is supported on a porous substrate such as a synthetic resin nonwoven fabric, and the activated carbon adsorbs and removes odorous components such as ammonia and hydrogen sulfide contained in the air.

[0032] Next, we will explain the configuration of the filter unit 12. As shown in Fig. 4, the filter unit 12 includes a photocatalytic filter 40 and a rectangular holding frame 42 that holds the photocatalytic filter 40. The photocatalytic filter 40 and the holding frame 42 are molded integrally.

[0033] The photocatalytic filter 40 is a flexible filter in which a photocatalyst (photocatalyst particles) is supported on a porous substrate such as a synthetic resin nonwoven fabric. The photocatalyst contained in the photocatalytic filter 40 is excited by irradiation with light such as ultraviolet light to generate active oxygen species, which then remove (sterilize) germs contained in the air and decompose (deodorize) odorous components. Known photocatalysts such as titanium oxide and tungsten oxide can be used as the photocatalyst, with titanium oxide being preferred among these.

[0034] The photocatalytic filter 40 is formed in a wave shape (also called a pleated or bellows shape) in which peaks 40a and valleys 40b extending in a first direction are alternately arranged in a second direction perpendicular to the first direction. In this embodiment, the photocatalytic filter 40 is formed in a triangular wave shape with folds 40c formed at the tip ends (tops and bottoms) of the peaks 40a and valleys 40b, and the plurality of folds 40c are formed to extend in the first direction. In this way, by forming the photocatalytic filter 40 in a wave shape (folded), it is possible to increase the contact area between the photocatalytic filter 40 and the air while suppressing an increase in the size of the photocatalytic filter 40.

[0035] The holding frame 42 includes a first frame 44 and a second frame 46 that hold the four sides of the photocatalytic filter 40. The holding frame 42 is made of a synthetic resin such as ABS resin or a PC / ABS alloy that is a mixture of ABS resin and polycarbonate.

[0036] The first frame 44 is a portion for maintaining the wavy shape of the photocatalytic filter 40, and is provided so as to cover both end portions in the first direction of the photocatalytic filter 40. This first frame 44 has openings 44a (first openings) that allow airflow to pass in the first direction, and is configured so as not to obstruct the airflow caused by the blower fan 16. Specifically, the first frame 44 is formed in a wavy shape that extends along the end portions in the first direction of the photocatalytic filter 40 (i.e., formed so as to extend wavy in the second direction), and openings 44a with a triangular cross section are formed between the inclined pieces that form the waves (peaks and valleys).

[0037] The second frame 46 is provided at both ends in the second direction of the photocatalytic filter 40. The second frame 46 is formed in the shape of a rectangular long plate extending in the first direction, and connects the ends of the first frame 44. The second frame 46 forms an air passage extending in the first direction, and restricts the diffusion of airflow in the second direction (i.e., outside the width of the photocatalytic filter 40).

[0038] The holding frame 42 further includes a third frame 48 that is provided to sandwich the center in the first direction of the photocatalytic filter 40. Similar to the first frame 44, the third frame 48 is a portion for maintaining the wavy shape of the photocatalytic filter 40, and has openings 48a that allow airflow to pass in the first direction. In this embodiment, the third frame 48 is formed so as to extend wavy in the second direction along the main surface of the photocatalytic filter 40.

[0039] As shown in FIG. 5, such a filter unit 12 can be attached to and detached from the unit accommodating portion 28 by opening an opening / closing cover 50 provided on one side surface of the housing 20.

[0040] 2 and 5, in this embodiment, the filter unit 12 (photocatalytic filter 40) is housed in the unit housing section 28 so that the airflow caused by the blower fan 16 flows along the first direction (i.e., the direction in which the folds 40c of the photocatalytic filter 40 extend). That is, the filter unit 12 is housed vertically in the unit housing section 28 so that the first direction is the up-down direction, and the airflow caused by the blower fan 16 flows along both main surfaces of the photocatalytic filter 40.

[0041] The unit accommodating section 28 is also provided with a unit guide 52 that guides the installation and removal of the filter unit 12, and the filter unit 12 is guided to the installation position by the unit guide 52. The unit guide 52 has an opening 52a (second opening) that communicates with the opening 44a of the first frame 44 and allows airflow to pass in a first direction (corresponding to the air blowing direction), and is configured not to obstruct the airflow caused by the blower fan 16. Specifically, a pair of unit guides 52 are provided at each of the upper and lower ends of the unit accommodating section 28, spaced a predetermined distance apart in the thickness direction of the filter unit 12 (a third direction perpendicular to the first and second directions) and extending in the installation and removal direction of the filter unit 12 (the second direction). Each of the unit guides 52 has an L-shaped cross section and slidably supports the first frame 44 provided with the filter unit 12. An opening 52a is formed between the pair of unit guides 52, and when the filter unit 12 is attached to the unit accommodating portion 28, the opening 52a communicates with the opening 44a.

[0042] In the sterilizing deodorizer 10 described above, when the power button 22a is turned on, the control unit 100 drives the blower fan 16 and turns on the light source 14 (LED 32) to irradiate both main surfaces of the photocatalytic filter 40 with light. Air is drawn into the housing 20 through the air intake 24 as the blower fan 16 is driven, and odorous components are first adsorbed and removed by the activated carbon filter 18. The air that passes through the activated carbon filter 18 then flows upward through the unit housing 28 along both main surfaces of the photocatalytic filter 40. When the photocatalytic filter 40 comes into contact with the air, organic matter adhering to the photocatalytic filter 40 is decomposed by photocatalytic action, thereby sterilizing and deodorizing the air. The clean air that has been sterilized and deodorized by the photocatalytic filter 40 is then discharged outside the housing 20 through the exhaust port 26.

[0043] In this case, the corrugated shape of the photocatalytic filter 40 increases the contact area between the photocatalytic filter 40 and the air, allowing for efficient sterilization and deodorization. Furthermore, since air flows along the main surfaces of the photocatalytic filter 40 rather than through the thickness direction of the photocatalytic filter 40, pressure loss can be reduced. In particular, pressure loss can be more appropriately reduced by flowing air along the first direction, which is the direction in which the peaks 40a and valleys 40b of the photocatalytic filter 40 extend. Furthermore, since air flows along both main surfaces of the photocatalytic filter 40 and light is irradiated onto both main surfaces of the photocatalytic filter 40 using the first light source 14a and the second light source 14b, sterilization and deodorization can be more efficiently performed. Furthermore, since the first frame 44 has an opening 44a and the unit guide 52 has an opening 52a, the first frame 44 and the unit guide 52 do not obstruct the air flow, allowing air to flow appropriately along both main surfaces of the photocatalytic filter 40.

[0044] Fig. 6 is a diagram schematically showing the structure of the sterilizing deodorizer 10 shown in Figs. 1 to 5. As shown in Fig. 6, the sterilizing deodorizer 10 further includes a dirt sensor 36, and as an example, the dirt sensor 36 is disposed between the filter unit 12 and the blower fan 16. However, the dirt sensor 36 may also be disposed between the filter unit 12 and the air intake 24. The dirt sensor 36 is an organic matter sensor (an odor sensor or a VOC sensor) and detects the degree of air pollution.

[0045] Fig. 7 is a block diagram showing the electrical configuration of the sterilization deodorizer 10 of the first embodiment. As shown in Fig. 7, the sterilization deodorizer 10 is equipped with the above-mentioned control unit 100. The control unit 100 includes a CPU 102, which is connected to a RAM 106, a ROM 108, an LED drive circuit 110, a blower fan drive circuit 112, and an input interface (hereinafter referred to as "input I / F") 114 via a bus 104.

[0046] Furthermore, the LED drive circuit 110 is connected to the light source 14, the blower fan drive circuit 112 is connected to the blower fan 16, and the input I / F 114 is connected to the operation unit 22 and the dirt sensor .

[0047] The CPU 102 is a processor that controls the overall control of the control unit 100. The RAM 106 and the ROM 108 are the main storage devices of the control unit 100. The RAM 106 is used as a working area and a buffer area for the CPU 102. The ROM 108 is an auxiliary storage device of the control unit 100, and stores a control program (firmware). However, the ROM 108 can also be a non-volatile memory such as an EEPROM or a flash memory.

[0048] Although not shown in the figure, a nonvolatile memory such as an HDD, SSD, or flash memory is provided as an auxiliary storage device in addition to the main storage device.

[0049] The LED drive circuit 110 is a circuit for driving the light source 14 (plurality of LEDs 32) under the instruction of the CPU 102. The blower fan drive circuit 112 is a circuit for driving the blower fan 16 under the instruction of the CPU 102.

[0050] The input I / F 114 outputs an operation signal input from the operation unit 22 to the CPU 102, and outputs a detection value (that is, a voltage value) input from the dirt sensor 36 to the CPU 102.

[0051] As described above, the sterilization and deodorization machine 10 is operated in one of the sterilization and deodorization operating modes, namely, silent mode, normal mode, and strong mode, and by flowing air taken in from outside along the main surface (surface) of the photocatalytic filter 40 and irradiating the photocatalytic filter 40 with light, the organic matter (organic compounds) adhering to the photocatalytic filter 40 is decomposed to perform sterilization and deodorization.

[0052] Figure 8 is a graph showing the change over time in the concentration of organic matter in the air, where curve (1) shows the change over time in the concentration of organic matter in the air when an excessive amount of organic matter is attached to the photocatalytic filter 40 (excessively dirty), and curve (2) shows the change over time in the concentration of organic matter in the air when a small amount of organic matter or no organic matter is attached to the photocatalytic filter 40 (little dirt or no dirt).

[0053] 8, when an excessive amount of organic matter adheres to the photocatalytic filter 40, the concentration of organic matter in the air is less likely to decrease even after a certain amount of time has passed, compared to when a small amount of organic matter adheres to the photocatalytic filter 40. In other words, when an excessive amount of organic matter adheres to the photocatalytic filter 40, the decomposition efficiency or decomposition speed by the photocatalyst decreases.

[0054] Therefore, in this first embodiment, when it is determined that the degree of organic matter adhering to the photocatalytic filter 40 (i.e., the degree of contamination) is excessive, the sterilizing deodorizer 10 is operated in a refresh operation mode (hereinafter referred to as the "refresh mode") that decomposes the organic matter adhering to the photocatalytic filter 40, thereby reducing contamination of the photocatalytic filter 40. In the refresh mode, the light source 14 is driven at a duty ratio of 100%, and the blower fan 16 is driven at a duty ratio of 25% or less (25% in this first embodiment). However, in the refresh mode, the air speed may be set to 0, i.e., the blower fan 16 may be stopped. In other words, the duty ratio of the blower fan 16 may be set to 0%. In other words, it is sufficient that the air speed is the slowest among the air speeds blown by the sterilizing deodorizer 10 during operation. Furthermore, the duty ratio applied to the light source 14 does not have to be 100%, and may be, for example, 90%, as long as it is the maximum light intensity emitted by the sterilizing deodorizer 10 during operation.

[0055] FIG. 9 is an example of a table showing criteria for determining the degree of contamination. As shown in FIG. 9, the table of contamination criteria lists contamination values ​​for each degree of contamination. As an example, the degree of contamination is determined on a three-level scale from 0 to 2. The higher the number, the dirtier the level. As described above, the contamination sensor 36 is a semiconductor-type VOC sensor, and its resistance value changes as the concentration of gases in the air increases. Using clean air as a reference, the degree of air contamination is calculated based on the change in the sensor's resistance value from that point. In other words, a clean air state (a state in which no VOCs are detected) is set to 1, and an internally processed value is output in the range of 0 to 1 (voltage value) depending on the degree of air contamination, approaching 0 as the detected concentration increases. This output value is called the contamination value. If the contamination value is 0.65 to 1, the degree of contamination is 0. If the contamination value is 0.35 to 0.65, the degree of contamination is 1. If the contamination value is 0 to 0.35, the degree of contamination is 2. In the first embodiment, if the contamination level is 2, it is determined that an excessive amount of organic matter is attached to the photocatalytic filter 40 (i.e., it is contaminated), and the sterilization and deodorization machine 10 is operated in refresh mode for a second predetermined time (10 minutes in the first embodiment).

[0056] In the graph shown in FIG. 8, the curve (1) is the curve when the contamination level is 2, and the curve (2) is the curve when the contamination level is 0.

[0057] In the first embodiment, the contamination of the photocatalytic filter 40 is checked, and if the photocatalytic filter 40 is found to be excessively dirty, a process (filter contamination confirmation process, described later) is executed to operate the sterilizing deodorizer 10 in refresh mode. However, when the power to the sterilizing deodorizer 10 is turned on, or periodically (every 30 minutes in the first embodiment) while the sterilizing deodorizer 10 is in operation, a process (confirmation execution judgment process, described later) is executed to determine whether or not to execute the filter contamination confirmation process. In other words, since it is not possible to determine whether the amount of organic matter adhering to the photocatalytic filter 40 is large or small unless the activity of the organic matter in the air drawn in by the blower fan 16 is high to a certain extent, a confirmation execution judgment process is executed in advance to determine whether or not to execute the filter contamination confirmation process.

[0058] In the filter contamination confirmation process, the blower fan 16 is driven under conditions that result in a predetermined air speed. In the first embodiment, the blower fan 16 is driven at a duty ratio of 50%. With the blower fan 16 driven, the light source 14 is driven at a first light intensity. In the first embodiment, each of the multiple LEDs 32 is driven at a duty ratio of 60%. However, the first light intensity may be 0. That is, the light source 14 may be turned off. With the light source 14 driven at the first light intensity, the detection value of the contamination sensor 36 is acquired every second, and the average value of a first predetermined number of detections (10 detections in the first embodiment) is stored as the first contamination value. In other words, the average value of the detection values ​​detected 10 times every second during the first predetermined time is stored as the first contamination value. However, 1 second and 10 times are merely examples and need not be limited thereto. The same applies to the second contamination value described below.

[0059] Next, the light source 14 is driven at a second light intensity that is greater than the first light intensity. In the first embodiment, each of the plurality of LEDs 32 is driven at a duty ratio of 80%. While the light source 14 is driven at the second light intensity, a detection value of the dirt sensor 36 is acquired every second, and the average value for a first predetermined number of times is stored as the second dirt value. In other words, the average value of detection values ​​detected 10 times every second during the first predetermined time period is stored as the second dirt value.

[0060] It is determined whether the process for calculating the first and second contamination values ​​has been performed a second predetermined number of times (five times in the first embodiment). The reason for setting the second predetermined number of times to multiple times is to increase detection accuracy. However, the second predetermined number of times may be one time. When the first and second contamination values ​​have been calculated the second predetermined number of times, the difference (first difference) between the first and second contamination values ​​for each calculation is calculated, and it is determined whether a first difference smaller than the first judgment value (a contamination value of 0.3 in the first embodiment) has been detected a third predetermined number of times (three times in the first embodiment).

[0061] As shown in Figure 8, when an excessive amount of organic matter adheres to the photocatalytic filter 40, the decomposition efficiency or decomposition speed by the photocatalyst decreases, so there is almost no change in the organic matter concentration in the air when the light source 14 is driven at the first light intensity and when the light source 14 is driven at the second light intensity.

[0062] Here, the first judgment value is determined within a range of contamination values ​​for which the contamination level is the same. As shown in Fig. 9, the range of contamination values ​​for contamination levels 0 and 2 is 0.35, and the range of contamination values ​​for contamination level 1 is 0.3. Therefore, in the first embodiment, the first judgment value is set to a voltage value corresponding to the contamination level range 0.3.

[0063] The third predetermined number is set to a value greater than half the second predetermined number but less than or equal to the second predetermined number. This is because if the third predetermined number is greater than half the second predetermined number, it can be said that there is a high probability that there will be almost no change in the organic substance concentration in the air. However, if the second predetermined number is 1, the third predetermined number is also 1.

[0064] When the first difference smaller than the first determination value is detected a third predetermined number of times or more, the blower fan 16 and the light source 14 are driven for a second predetermined time in refresh mode.

[0065] That is, in the first embodiment, one contamination sensor 36 is used to determine whether the photocatalytic filter 40 is excessively contaminated based on the change in organic matter concentration when the photocatalytic filter 40 is irradiated with different amounts of light, and if the photocatalytic filter 40 is excessively contaminated, the sterilization deodorizer 10 is operated in refresh mode to refresh the photocatalytic filter 40. That is, the decomposition of organic matter adhering to the photocatalytic filter 40 is promoted, and the decomposition efficiency or decomposition speed is restored.

[0066] FIG. 10 is an example of a table showing information about operation control (hereinafter referred to as "operation control table"). As shown in FIG. 10, the information about operation control sets illuminance and wind speed for each operation mode. As an example, there are four operation modes: silent mode, normal mode, strong mode, and refresh mode. Each mode has been described above, so a duplicated explanation will be omitted. As an example, the operation control table is stored in ROM 108, and when an operation mode is determined, the operation control table stored in ROM 108 is referenced, and the driving of light source 14 and blower fan 16 is controlled according to the operation mode.

[0067] However, the illuminance indicates the duty ratio when the light source 14 is driven, and the wind speed indicates the duty ratio when the blower fan 16 is driven.

[0068] Fig. 11 is a diagram showing an example of a memory map of the RAM 106 shown in Fig. 7. As shown in Fig. 11, the RAM 106 includes a program storage area 302 and a data storage area 304. The program storage area 302 stores the control program of the first embodiment executed by the CPU 102 of the sterilizing deodorizing machine 10.

[0069] The control programs include an operation detection program 302a, a fan control program 302b, a light source control program 302c, a dirt check program 302d, and a check execution determination program 302e.

[0070] The operation detection program 302a is a program for detecting an operation signal input from the operation unit 22 and storing corresponding operation data 304a in the data storage area 304. The fan control program 302b is a program for controlling the driving of the blower fan 16 in accordance with the operation mode. The light source control program 302c is a program for controlling the lighting of the plurality of LEDs 32 included in the light source 14 in accordance with the operation mode.

[0071] The contamination confirmation program 302d is a program for confirming the degree of contamination of the photocatalytic filter 40 and, if necessary, switching the operation mode to the refresh mode. The confirmation execution decision program 302e is a program for determining whether to execute the contamination confirmation program 302d.

[0072] Although not shown in the drawings, the program storage area 302 also stores other programs necessary for controlling the sterilization deodorization machine 10.

[0073] The data storage area 304 stores operation data 304a, operation mode data 304b, first contamination value data 304c, second contamination value data 304d, and confirmation value data 304e.

[0074] The operation data 304a is data corresponding to an operation signal detected in accordance with the operation detection program 302a. The operation mode data 304b is data for identifying the currently set operation mode, specifically, the silent mode, normal mode, strong mode, or refresh mode.

[0075] The first contamination value data 304c is data of the first contamination value calculated based on the detection value of the contamination sensor 36 when the blower fan 16 is driven under conditions that result in a predetermined wind speed and the photocatalytic filter 40 is irradiated with a first light amount during execution of the contamination confirmation program 302d.

[0076] The second contamination value data 304d is data of the second contamination value calculated based on the detection value of the contamination sensor 36 when the blower fan 16 is driven under conditions that result in a predetermined wind speed and the photocatalytic filter 40 is irradiated with a second light amount that is greater than the first light amount during execution of the contamination confirmation program 302d.

[0077] The confirmation value data 304e is data on a confirmation value for determining whether or not to execute the filter contamination confirmation process during execution of the confirmation execution determination program 302e.

[0078] Although not shown, the data storage area 304 also stores other data, flags, and timers (not shown) required for controlling the sterilization deodorization machine 10.

[0079] Fig. 12 is a flow diagram of the filter dirt confirmation process by CPU 102 shown in Fig. 7. Fig. 13 is a flow diagram of the confirmation execution determination process by CPU 102 shown in Fig. 7. When it is determined in the confirmation execution determination process shown in Fig. 13 that the dirt confirmation process is to be executed, the filter dirt confirmation process shown in Fig. 12 is started.

[0080] 12, when the CPU 102 starts the filter contamination checking process, in step S1, the CPU 102 drives the blower fan 16 under conditions that result in a predetermined air speed. Here, the CPU 102 controls the blower fan drive circuit 112 to drive the blower fan 16 at a duty ratio of 50%.

[0081] In the next step S3, the light source 14 is driven with the first light amount. Here, the CPU 102 controls the LED drive circuit 110 to drive each of the plurality of LEDs 32 with a duty ratio of 60%.

[0082] Next, in step S5, the CPU 102 acquires a detection value from the dirt sensor 36 every second, and stores the average value of a first predetermined number of times (for example, 10 times) as the first dirt value. The reason for setting the first predetermined number of times to a plurality of times is to increase detection accuracy. That is, the CPU 102 stores the first dirt value data 304c in the data storage area 304.

[0083] Next, in step S7, the light source 14 is driven at a second light amount that is greater than the first light amount. Here, the CPU 102 controls the LED drive circuit 110 to drive each of the plurality of LEDs 32 at a duty ratio of 80%.

[0084] Next, in step S9, the CPU 102 obtains the detection value of the dirt sensor 36 every second and stores the average value of the first predetermined number of times as the second dirt value. That is, the CPU 102 stores the second dirt value data 304d in the data storage area 304.

[0085] In step S11, it is determined whether the processing of steps S3 to S9 has been performed a second predetermined number of times (for example, five times). If the determination in step S11 is "NO," that is, if the processing of steps S3 to S9 has not been performed the second predetermined number of times, the process returns to step S3.

[0086] On the other hand, if the answer is "YES" in step S11, that is, if the processing of steps S3 to S9 has been performed a second predetermined number of times, then in step S13 it is determined whether a first difference smaller than the first judgment value has been detected a third predetermined number of times (for example, three times) or more.

[0087] If step S13 is "NO," that is, if the first difference smaller than the first determination value has not been detected a third predetermined number of times or more, the filter dirt confirmation process is terminated. On the other hand, if step S13 is "YES," that is, if the first difference smaller than the first determination value has been detected a third predetermined number of times or more, in step S15, the light source 14 and the blower fan 16 are driven in refresh mode for a second predetermined time (for example, 10 minutes), and the filter dirt confirmation process is terminated.

[0088] As described above, the confirmation execution judgment process, which is performed in advance to determine whether or not to perform the filter dirt confirmation process, is performed when the power to the sterilization and deodorization machine 10 is turned on, or periodically (for example, every 30 minutes) while the sterilization and deodorization machine 10 is operating.

[0089] 13, when the CPU 102 starts the confirmation execution determination process, it stops driving the light source 14 in step S31, and drives the fan under conditions that result in a predetermined wind speed in step S33. Here, the CPU 102 controls the blower fan drive circuit 112 to drive the blower fan 16 at a duty ratio of 50%.

[0090] In the next step S35, the detection value is acquired, and in the next step S37, the contamination level corresponding to the detection value is stored as a confirmation value. That is, the CPU 102 stores confirmation value data 304e in the data storage area 304.

[0091] Then, in step S39, it is determined whether the confirmation value is greater than a first predetermined value. If step S39 returns "NO," that is, if the confirmation value is equal to or less than the first predetermined value, the confirmation execution determination process ends. On the other hand, if step S39 returns "YES," that is, if the confirmation value is greater than the first predetermined value, the filter contamination confirmation process shown in FIG. 12 is started.

[0092] As described above, according to the first embodiment, when an excessive amount of organic matter adheres to the photocatalytic filter, the photocatalytic filter is refreshed, so that the organic matter adhered to the photocatalytic filter is decomposed and the decomposition efficiency of the photocatalytic filter can be restored. Therefore, sterilization and deodorization can be performed efficiently. Furthermore, the photocatalytic filter can be refreshed at an appropriate timing.

[0093] Furthermore, according to this first embodiment, the detection values ​​of each contamination sensor when the photocatalytic filter is irradiated with different amounts of light are compared, so that the degree of organic matter adhering to the photocatalytic filter, i.e., the degree of contamination, can be easily determined.

[0094] [Second Example] The sterilization and deodorization machine 10 of the second embodiment is the same as the first embodiment except that a dirt sensor is further provided between the air intake 24 and the filter unit 12, and whether or not to set the refresh mode is determined based on the detection values ​​of the two dirt sensors, so duplicated explanations will be omitted.

[0095] Figure 14 is a diagram schematically illustrating the structure of the sterilization deodorization machine 10 of the second embodiment. In the second embodiment, two dirt sensors are provided, and therefore, as shown in Figure 14, the dirt sensor 36 between the filter unit 12 and the blower fan 16 will be referred to as the first dirt sensor 36, and the dirt sensor 38 additionally provided between the air intake 24 and the filter unit 12 will be referred to as the second dirt sensor 38.

[0096] 15 is a block diagram showing the electrical configuration of the sterilization deodorization machine 10 of the second embodiment. In the second embodiment, the second dirt sensor 38 is also connected to the input I / F 114.

[0097] 16 is a flow chart showing the filter contamination confirmation process of the second embodiment. The filter contamination confirmation process of the second embodiment will be described below, but the same content as the filter contamination confirmation process of the first embodiment will be briefly described.

[0098] 16, when the CPU 102 starts the filter dirt confirmation process, in step S61, it drives the blower fan 16 under conditions that result in a predetermined wind speed, and in step S63 it determines whether the detection value of the second dirt sensor 38 is greater than a second predetermined value. For example, the second predetermined value is set to the detection value (i.e., voltage value) of the second dirt sensor 38 that corresponds to the dirt value of 0.35.

[0099] If step S63 is "NO," that is, if the detection value of the second dirt sensor 38 is less than the second predetermined value, the filter dirt confirmation process ends. On the other hand, if step S63 is "YES," that is, if the detection value of the second dirt sensor 38 is greater than the second predetermined value, in step S65, the light source 14 and the blower fan 16 are driven under predetermined conditions, here in silent mode (see FIG. 10), for a third predetermined time (e.g., 10 seconds).

[0100] In the next step S67, the difference between the detection value of the second contamination sensor 38 and the detection value of the first contamination sensor 36 at the third predetermined time (for convenience of explanation, referred to as the "second difference") is calculated and stored. In other words, the change in the concentration of organic matter in the air before and after sterilization and deodorization by the photocatalytic filter 40 is calculated.

[0101] In step S69, it is determined whether the processes of steps S65 and S67 have been performed a fourth predetermined number of times (for example, five times), although the fourth predetermined number of times may be one time.

[0102] If step S69 is "NO," that is, if the processes of steps S65 and S67 have not been performed a fourth predetermined number of times, the process returns to step S65. On the other hand, if step S69 is "YES," that is, if the processes of steps S65 and S67 have been performed a fourth predetermined number of times, step S71 determines whether a second difference smaller than the second determination value (e.g., 0.3) has been detected a fifth predetermined number of times (e.g., three times). In other words, the CPU 102 determines whether the photocatalytic filter 40 is excessively dirty. In the second embodiment, the second determination value is the same as the first determination value in the first embodiment.

[0103] If step S71 is "NO," that is, if a second difference smaller than the second determination value has not been detected a fifth predetermined number of times, the filter dirt confirmation process is terminated. On the other hand, if step S71 is "YES," that is, if a second difference smaller than the second determination value has been detected a fifth predetermined number of times, the light source 14 and the blower fan 16 are driven in refresh mode for a fourth predetermined time (for example, 10 minutes) in step S73, and the filter dirt confirmation process is terminated.

[0104] 13 is the same for the second embodiment, and therefore a description thereof will be omitted. However, the confirmation execution determination process may be performed using the detection value of the second dirt sensor 38 instead of the detection value of the first dirt sensor 36.

[0105] In the second embodiment, as in the first embodiment, if an excessive amount of organic matter adheres to the photocatalytic filter, the photocatalytic filter is refreshed, which promotes the decomposition of the organic matter adhered to the photocatalytic filter and restores the decomposition efficiency of the photocatalytic filter. Therefore, efficient sterilization and deodorization are possible. Furthermore, the photocatalytic filter can be refreshed at an appropriate timing.

[0106] Furthermore, according to this second embodiment, a dirt sensor is provided on both the upstream side and downstream side of the photocatalytic filter in the direction of airflow from the blower fan, and the detection values ​​of each dirt sensor are compared when the photocatalytic filter is irradiated with a predetermined amount of light, so that the degree of organic matter adhering to the photocatalytic filter, i.e., the degree of dirt, can be easily determined.

[0107] [Third Example] The sterilization and deodorization machine 10 of the third embodiment is the same as the first embodiment except that the photocatalytic filter 40 is refreshed at the end of operation of the sterilization and deodorization machine 10 regardless of whether the photocatalytic filter 40 is dirty or not, so a duplicated explanation will be omitted.

[0108] In the sterilizing deodorizing machine 10 of the third embodiment, whether or not the photocatalytic filter 40 is contaminated is not a factor, and therefore the contamination sensor 36 is not necessary.

[0109] In the third embodiment, the fifth predetermined time for operating the sterilizing deodorizer 10 in the refresh mode is determined according to the operating time in the quiet mode, normal mode, or strong mode. As an example, if the operating time in the quiet mode, normal mode, or strong mode is less than three hours, the operating time in the refresh mode (i.e., the fifth predetermined time) is set to 10 minutes. If the operating time in the quiet mode, normal mode, or strong mode is between three hours and six hours, the operating time in the refresh mode is set to 20 minutes. If the operating time in the quiet mode, normal mode, or strong mode is six hours or more, the operating time in the refresh mode is set to 30 minutes.

[0110] FIG. 17 is a flow chart showing the refresh control process of the third embodiment. This refresh control process is started when the sterilizing and deodorizing machine 10 starts operation in the sterilizing and deodorizing operation mode. As shown in FIG. 17, when the refresh control process starts, the CPU 102 starts measuring the operation time in the sterilizing and deodorizing operation mode in step S91. In the following step S93, it is determined whether operation in the sterilizing and deodorizing operation mode has ended. If "NO" in step S93, that is, if operation has not ended, the process returns to step S93. On the other hand, if "YES" in step S93, that is, if operation has ended, the operation time is stored in step S95.

[0111] In the next step S97, a fifth predetermined time for the refresh mode is determined based on the stored operation time. Then, in step S99, the light source 14 and the blower fan 16 are driven for the fifth predetermined time in the refresh mode, and the refresh control process is terminated.

[0112] According to the third embodiment, the photocatalytic filter is refreshed at the end of the sterilization and deodorization operation mode, so that organic matter adhering to the photocatalytic filter is decomposed and the decomposition efficiency of the photocatalytic filter can be restored. Therefore, as in the first embodiment, sterilization and deodorization can be performed efficiently. Furthermore, the photocatalytic filter can be refreshed at an appropriate timing.

[0113] In the above-described embodiments, the light sources are arranged on both sides of the filter unit, but the light sources may be arranged on only one side of the filter unit. Also, a reflector may be provided on the side where the light source is not arranged.

[0114] In addition, in each of the above-described embodiments, the blower fan generates an upward airflow, but the flow direction of the airflow generated by the blower fan can be changed as appropriate. For example, the blower fan can generate a horizontal airflow, and the filter unit can be arranged horizontally so that this airflow flows along the first direction. In other words, the arrangement direction of the filter unit can be either vertical or horizontal. Furthermore, the photocatalytic filter can be a filtering type.

[0115] The specific numerical values ​​and part shapes given above are merely examples and can be changed as needed depending on the product specifications, etc. [Explanation of symbols]

[0116] 10...Sterilization and deodorization machine 12...Filter unit 14...light source 16...Ventilation fan 20...Case 24...Air intake 26...Exhaust port 28... Unit housing section 36, 38 ... Dirt sensor 40...Photocatalytic filter 40c...crease 42...holding frame 44...1st frame 46...2nd frame 48...3rd frame 52...Unit Guide 100...control unit 102...CPU

Claims

1. A sterilizing deodorizer comprising: a blower fan; a photocatalytic filter carrying a photocatalyst; a light source for irradiating the photocatalytic filter; and a first sensor disposed downstream of the photocatalytic filter in the direction of airflow by the blower fan, the first sensor detecting organic matter contained in the air, a control unit that causes the light source to emit a maximum light amount that is the greatest amount of light emitted by the sterilizing deodorizer during operation, and drives the blower fan at a minimum wind speed that is the slowest wind speed at which the sterilizing deodorizer blows air during operation, thereby refreshing the photocatalytic filter; The control unit executes a first confirmation process to confirm the amount of organic matter adhering to the photocatalytic filter from the difference in the detection value detected by the first sensor when the light source is made to emit light at two different light intensities, and determines whether or not the photocatalytic filter needs to be refreshed based on the results of the first confirmation process.

2. 2. The sterilizing deodorizing machine according to claim 1, wherein, in the first confirmation process, the control unit detects a first difference between a first detection value of the first sensor when the light source is driven at a first light intensity for a first predetermined time and a second detection value of the first sensor when the light source is driven at a second light intensity greater than the first light intensity for the first predetermined time, and if the first difference is smaller than a first determination value, causes the light source to emit light at the maximum light intensity greater than the second light intensity, drives the blower fan at a minimum air speed, and refreshes the photocatalytic filter.

3. 3. The sterilizing deodorizing machine according to claim 1, wherein the first confirmation process is executed when the detection value of the first sensor in a state where the light source is turned off is equal to or greater than a first predetermined value.

4. the first difference is calculated a first predetermined number of times, which is equal to or greater than two; 3. The sterilizing deodorizing machine according to claim 2, wherein the control unit refreshes the photocatalytic filter when the number of times the first difference is smaller than the first determination value is detected a second predetermined number of times.

5. A sterilizing and deodorizing machine comprising a blower fan, a photocatalytic filter carrying a photocatalyst, a light source for irradiating the photocatalytic filter, and a first sensor disposed downstream of the photocatalytic filter in the direction of airflow by the blower fan, the first sensor detecting organic matter contained in the air, a control unit that causes the light source to emit a maximum amount of light that is the greatest amount of light emitted by the sterilizing deodorizer during operation, and drives the blower fan at a minimum wind speed that is the slowest wind speed at which the sterilizing deodorizer blows air during operation, thereby refreshing the photocatalytic filter; a second sensor for detecting organic matter contained in the air, the second sensor being located upstream of the photocatalytic filter in the direction of airflow by the blower fan; When the detection value of the second sensor when the blower fan is driven under the condition of a first predetermined wind speed is greater than a second judgment value, the control unit causes the light source to emit light at a predetermined light intensity and executes a second confirmation process to confirm the dirtiness of the photocatalytic filter from a second difference between the detection value of the second sensor when the blower fan is driven under the condition of a second predetermined wind speed.

6. 6. The sterilizing deodorizing machine according to claim 5, wherein when the second difference is smaller than a third judgment value, the control unit causes the light source to emit light at the maximum light intensity and drives the blower fan at a minimum wind speed to refresh the photocatalytic filter.

7. 7. The sterilizing deodorizing machine according to claim 5, wherein the second confirmation process is executed when the detected value of the first sensor or the second sensor is equal to or greater than a first predetermined value when the light source is turned off.

8. the second difference is calculated a third predetermined number of times, which is equal to or greater than two; 7. The sterilizing deodorizing machine according to claim 6, wherein the control unit refreshes the photocatalytic filter when the number of times the second difference is smaller than the third determination value is detected a fourth predetermined number of times.

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