JP2011097861A - Apparatus and method for detecting microorganism - Google Patents

Abstract

Provided is a microorganism detecting apparatus capable of separating and detecting organism-derived particles from dust in real time.
A sensor mechanism 20 of a microorganism detection apparatus 100A includes a case 5 having an introduction hole 10 and a discharge hole 11, a signal processing unit 30, and a measurement unit 40 therein, and the detection mechanism and collection in the case 5. And a mechanism. By introducing air into the case 5 for a predetermined time, particles in the air charged in the vicinity of the discharge electrode 1 are electrostatically adsorbed to the collection jig 12. Thereafter, the collection jig 12 is irradiated with light from the light emitting element 6, and infrared light is emitted from the microorganisms on the collection jig 12 excited thereby. Infrared light is received by the light receiving element 9, and the microorganism concentration is calculated based on the amount of light in the measuring unit 40.
[Selection] Figure 2

Description

  The present invention relates to a microorganism detection apparatus and a detection method, and more particularly, to a microorganism detection apparatus and a detection method for detecting organism-derived particles in the air.

  Conventionally, in the detection of microorganisms in the air, microorganisms in the air are collected by methods such as the falling bacteria method, collision method, slit method, perforated plate method, centrifugal collision method, impinger method, and filter method, and then cultured. Count the colonies that appear. However, this method requires 2 to 3 days for culturing and is difficult to detect in real time. Therefore, in recent years, as in Japanese Patent Application Laid-Open No. 2003-38163 (Patent Document 1) and Japanese Translation of PCT International Publication No. 2008-508527 (Patent Document 2), ultraviolet light is irradiated to microorganisms in the air, and fluorescence emission from the microorganisms is observed. There has been proposed an apparatus for detecting the number of pieces and detecting the number.

  In the conventional apparatus proposed in Patent Documents 1 and 2, as a means for determining whether the suspended particles are derived from living organisms, a method for determining whether to emit fluorescence by irradiation with ultraviolet rays is employed. .

JP 2003-38163 A Special table 2008-508527

  However, the dust that actually floats in the air contains a lot of chemical fibers that emit fluorescence when irradiated with ultraviolet light. Therefore, when the conventional apparatus proposed in Patent Documents 1 and 2 is used, dust that emits fluorescence is detected in addition to biological particles present in the air. That is, the conventional devices as proposed in Patent Documents 1 and 2 have a problem that it is impossible to accurately evaluate only biological particles present in the air.

  The present invention has been made in view of such problems, and provides a microorganism detection apparatus and a detection method capable of detecting biological particles separately from fluorescent dust in real time. It is aimed.

  In order to achieve the above object, according to one aspect of the present invention, a microorganism detecting apparatus includes a light emitting element, a light receiving element for receiving infrared light, at least light emission by the light emitting element and light reception by the light receiving element. And a control means for controlling the flow rate and the introduced fluid based on infrared light from particles in the introduced fluid received by the light receiving element by irradiating the introduced fluid with the light emitting element. Calculating means for calculating the amount of biologically-derived particles among the particles in the fluid.

  Preferably, the microorganism detection apparatus further includes a collection jig for collecting particles in the introduced fluid, the light emitting element is provided with an irradiation direction as a direction toward the collection jig, and the calculation means includes Infrared light quantity from particles collected on the collection jig received by the light receiving element by irradiating the collection jig with the light emitting element, and pre-stored infrared light quantity Based on the relationship with the amount of biological particles, the amount of biological particles among the particles in the introduced fluid is calculated.

More preferably, the collection jig is replaceable.
More preferably, the microorganism detection apparatus further includes means for removing particles collected by the collection jig.

  Preferably, the microorganism detection apparatus further includes an input unit for inputting an instruction to change the relationship between the infrared light amount and the amount of particles derived from living organisms.

  Preferably, the control means further controls the introduction of the fluid, the first control for introducing the fluid and collecting the particles in the fluid by the collecting jig, and the light receiving element after the first control. A second control for starting light reception of the light receiving element, starting light emission by the light emitting element after the start of light reception, and ending light reception by the light receiving element after a predetermined measurement time from the start of light emission by the light emitting element; To do.

  More preferably, in the first control, the control means ends the introduction of the fluid after a predetermined collection time has elapsed from the start of the introduction of the fluid.

  Preferably, the microorganism detection apparatus further includes an introducing unit for introducing the fluid at a predetermined flow rate, and the light emitting element is provided with the irradiation direction as a direction intersecting with the flow path of the fluid introduced by the introducing unit, and the calculating unit The number of received light per unit time of the infrared light from the particles in the introduced fluid crossing the irradiation from the light emitting element in the light receiving element by irradiating the flow path with the light emitting element, the flow rate, Based on the above, the amount of biological particles among the particles in the introduced fluid is calculated.

  More preferably, the calculation means counts the number of receptions of the pulse signal corresponding to the amount of infrared light received from the light receiving element.

  Preferably, the microorganism detecting apparatus further includes a filter for suppressing light having a wavelength from the light emitting element and fluorescence from the biological particles to the light receiving element.

  Preferably, the microorganism detection apparatus further includes a display unit for displaying a calculation result of the calculation unit as a measurement result.

Preferably, the light emitting element emits light in a wavelength range from ultraviolet to blue.
More preferably, the light emitting element emits light having a wavelength in the range of 190 nm to 450 nm.

  According to another aspect of the present invention, a detection method includes: a light emitting element; a light receiving element for receiving infrared light; and a calculating means for calculating the amount of biological particles contained in the introduced fluid. A method for detecting microorganisms in a microorganism detection apparatus, comprising: receiving a signal from a light receiving element in accordance with an amount of received infrared light from particles in the introduced fluid irradiated by the light emitting element. And calculating the amount of biologically derived particles among the particles in the introduced fluid using the received signal.

  Preferably, the microorganism detecting apparatus further includes a collecting jig for collecting particles in the introduced fluid, and the light emitting element is provided with an irradiation direction as a direction toward the collecting jig and receives a signal. In the step, a signal corresponding to the amount of infrared light from the particles collected on the collecting jig received by the light receiving element by irradiating the collecting jig with the light emitting element is received, and the biological origin In the step of calculating the amount of particles, the amount of biological particles among the particles in the fluid introduced based on the relationship between the amount of infrared light and the amount of particles stored in advance and the amount of biological particles Is calculated.

  Preferably, the detection method includes a step of introducing a fluid into the microorganism detection apparatus and collecting particles in the fluid with a collection jig before the step of receiving the signal, and the step of receiving the signal includes: After the fluid is introduced, light reception by the light receiving element is started, light emission by the light emitting element is started after light reception is started, and light reception by the light receiving element is terminated after a predetermined measurement time from the start of light emission by the light emitting element. A step of controlling the light receiving element and the light emitting element.

  More preferably, in the step of collecting the particles in the fluid with the collection jig, after the predetermined collection time has elapsed from the start of the introduction of the fluid, the introduction of the fluid is terminated and the light receiving element and the light emitting element are controlled. In this step, light reception by the light receiving element is started after completion of the introduction of the fluid.

  Preferably, the light emitting element is provided in a direction that intersects the flow path of the fluid to be introduced, and in the step of receiving a signal, irradiation from the light emitting element is performed by irradiating the light path with the light emitting element. In the step of receiving the signal corresponding to the amount of infrared light from the particles in the fluid introduced at a predetermined flow velocity in the flow path across the flow path and calculating the amount of biological particles, the signal is received per unit time. Based on the number of times and the flow velocity, the amount of biologically derived particles among the particles in the introduced fluid is calculated.

  According to the present invention, it is possible to detect biological particles from dust in real time and with high accuracy.

It is a figure which shows the specific example of the external appearance of the air cleaner as a microorganisms detection apparatus concerning embodiment. It is a figure which shows the basic composition of the microorganisms detection apparatus part of the air cleaner concerning 1st Embodiment. It is a figure explaining the structure of the detection mechanism of the air cleaner concerning 1st Embodiment. It is the schematic of the structure of the microorganisms detection apparatus used for inventors' experiment. It is a figure showing the infrared-light spectrum before and after ultraviolet light irradiation measured from the collection jig | tool before attaching yeast to a collection jig | tool as a result of inventors' experiment. It is a figure showing the infrared-light spectrum before and behind ultraviolet light measurement measured from the collection jig | tool which made yeast adhere to the collection jig | tool as a result of inventors' experiment. It is a block diagram which shows the specific example of a function structure as a microorganisms detection apparatus concerning 1st Embodiment. It is a time chart which shows the flow of the control concerning 1st Embodiment in a microorganisms detection apparatus. It is a figure which shows the specific example of the correspondence of infrared light quantity and microbe density | concentration. It is a figure which shows the example of a display of a detection result, and the display method. It is a figure which shows the correspondence of the density | concentration of the yeast attached to the collection jig | tool obtained by inventors' experiment, and an infrared light quantity. It is a figure explaining the structure of the detection mechanism of the air cleaner concerning 2nd Embodiment. It is a block diagram which shows the specific example of a function structure as a microorganisms detection apparatus concerning 2nd Embodiment. It is a figure which shows the other system configuration example of a microorganisms detection apparatus.

  Embodiments of the present invention will be described below with reference to the drawings. In the following description, the same parts and components are denoted by the same reference numerals. Their names and functions are also the same.

  In the embodiment, it is assumed that the air purifier shown in FIG. 1 functions as the microorganism detection device 100A according to the first embodiment or the microorganism detection device 100B according to the second embodiment. Referring to FIG. 1, an air cleaner as microorganism detection device 100A or microorganism detection device 100B includes a switch 110 for receiving an operation instruction, and a display panel 130 for displaying a detection result and the like. In addition, a suction port for introducing air, an exhaust port for exhausting, and the like, which are not shown, are included. Furthermore, the microorganism detection apparatus 100A includes a communication unit 150 for mounting a recording medium. The communication unit 150 may be for connecting a personal computer (PC) 300 as an external device with the cable 400. Or the communication part 150 may be for connecting the communication line for communicating with another apparatus via the internet. Alternatively, the communication unit 150 may be for communicating with other devices by infrared communication or Internet communication.

[First Embodiment]
Referring to FIG. 2, a microorganism detection device 100A that is a detection device portion of an air cleaner has a case 5 provided with an introduction hole 10 and a discharge hole 11 for introducing air from a suction port. 5, the sensor mechanism 20 including the signal processing unit 30 and the measurement unit 40 therein is included.

An air introduction mechanism 50 is provided in the microorganism detection apparatus 100A. Air from the suction port is introduced into the case 5 by the air introduction mechanism 50. The air introduction mechanism 50 may be, for example, a fan or pump installed outside the case 5 and a drive mechanism thereof. Further, for example, a heat heater, a micro pump, a micro fan, and a driving mechanism thereof incorporated in the case 5 may be used. Further, the air introduction mechanism 50 may be configured in common with the air introduction mechanism of the air purification device portion of the air cleaner. Preferably, the drive mechanism included in the air introduction mechanism 50 is controlled by the measurement unit 40, and the flow rate of the introduced air is controlled. Preferably, the flow rate of air introduced by the air introduction mechanism 50 is 1 L (liter) / min to 50 m ³ / min.

The sensor mechanism 20 includes a detection mechanism and a collection mechanism.
A known collection mechanism can be adopted as the collection mechanism. In FIG. 2, the case where the collection mechanism currently disclosed by Unexamined-Japanese-Patent No. 2003-214997 is employ | adopted as an example is shown. That is, referring to FIG. 2, the collection mechanism includes a discharge electrode 1, a collection jig 12, and a high voltage power supply 2. The discharge electrode 1 is electrically connected to the negative electrode of the high voltage power source 2. The positive electrode of the high voltage power supply 2 is grounded. Thereby, the airborne particles introduced in the air are negatively charged in the vicinity of the discharge electrode 1. The collection jig 12 is a support substrate 4 made of a glass plate or the like having a conductive transparent film 3. The film 3 is grounded. As a result, the negatively charged airborne particles in the air move toward the collecting jig 12 by electrostatic force and are adsorbed by the conductive film 3 to be collected on the collecting jig 12. The

  The support substrate 4 is not limited to a glass plate, but may be ceramic, metal, or the like. Further, the coating 3 formed on the surface of the support substrate 4 is not limited to being transparent. As another example, the support substrate 4 may be configured by forming a metal film on an insulating material such as ceramic. Moreover, when the support substrate 4 is a metal material, it is not necessary to form a film on the surface.

  The detection mechanism includes a light-emitting element 6 that is a light source, a lens (or a lens group) 7 that is provided in the irradiation direction of the light-emitting element 6 and makes the light from the light-emitting element 6 parallel light or has a predetermined width. Aperture 8, light receiving element 9, and infrared light generated by irradiating floating fine particles collected on light collecting element 12 by light collecting element 6 from light emitting element 6 in the light receiving direction of light receiving element 9. A condensing lens (or lens group) 13 for condensing on the light receiving element 9, and a filter (or filter group) 14 for preventing fluorescence from irradiation light or biological particles from entering the light receiving element 9. Including. Among these, the aperture 8 is provided as needed. Conventional technology can be applied to these configurations.

  The light emitting element 6 includes a semiconductor laser or an LED (Light Emitting Diode) element. The wavelength may be in the ultraviolet or visible region as long as it excites the fine particles derived from living organisms and emits infrared light. Preferably, it is 190 nm to 450 nm, and more preferably, it is 300 nm to 450 nm where tryptophan, NaDH, riboflavin, etc. contained in the microorganism are efficiently excited as disclosed in JP-A-2008-508527. . As the light receiving element 9, a conventionally used photodiode, image sensor, or the like is used.

  Both the lens 7 and the condenser lens 13 may be made of plastic resin or glass. Due to the combination of the lens 7 and the aperture 8, the light emitted from the light emitting element 6 is irradiated onto the surface of the collecting jig 12, and an irradiation region 15 is formed on the collecting jig 12. The shape of the irradiation region 15 is not limited, and may be a circle, an ellipse, a rectangle, or the like. The irradiation area 15 is not limited to a specific size, but preferably, the diameter of the circle, the length of the ellipse in the long axis direction, or the length of one side of the rectangle is about 0.05 mm to 50 mm.

  The filter 14 is configured by a single or a combination of several types of filters, and is installed in front of the condenser lens 13 or the light receiving element 9. Thereby, the infrared light from the particles collected by the collecting jig 12 and the stray light reflected from the light emitting element 6 on the collecting jig 12 and the case 5 and the excitation of the biological particles are caused. Incidence of the emitted fluorescence to the light receiving element 9 can be suppressed.

  Case 5 is a rectangular parallelepiped having a length of 3 mm to 500 mm on each side. In the present embodiment, the shape of the case 5 is a rectangular parallelepiped, but is not limited to a rectangular parallelepiped, and may be another shape. Preferably, at least the inside is applied with a black paint or a black alumite treatment. Thereby, reflection of light on the inner wall surface that causes stray light is suppressed. The material of the case 5 is not limited to a specific material, but a plastic resin, a metal such as aluminum or stainless steel, or a combination thereof is preferably used. The introduction hole 10 and the discharge hole 11 provided in the case 5 are circular with a diameter of 1 mm to 50 mm. The shapes of the introduction hole 10 and the discharge hole 11 are not limited to a circle, but may be other shapes such as an ellipse or a rectangle.

  As described above, the filter 14 is installed in front of the light receiving element 9 and serves to prevent stray light and fluorescence from entering the light receiving element 9. However, in order to obtain a larger light emission intensity, it is necessary to increase the light emission intensity in the light emitting element 6. This leads to an increase in reflected light intensity, that is, stray light intensity. Therefore, the light emitting element 6 and the light receiving element 9 are preferably arranged in a positional relationship such that the stray light intensity does not exceed the light shielding effect of the filter 14.

  An example of the arrangement of the light-emitting element 6 and the light-receiving element 9 will be described with reference to FIGS. 2, 3 (A), and 3 (B). 3A is a cross-sectional view of the microorganism detection device 100A as viewed from the AA position in FIG. 2 in the direction of arrow A, and FIG. 3B is an arrow from the BB position in FIG. 3A. It is sectional drawing seen in the B direction. For convenience of explanation, these drawings do not show a collecting mechanism other than the collecting jig 12.

  Referring to FIG. 3A, light emitting element 6 and lens 7, light receiving element 9 and condenser lens 13 are provided at a right angle or a substantially right angle when viewed from the direction of arrow A (upper surface) in FIG. The reflected light from the irradiation region 15 formed on the surface of the collecting jig 12 from the light emitting element 6 through the lens 7 and the aperture 8 is directed in the direction along the incident light. Therefore, with this configuration, the reflected light does not directly enter the light receiving element 9. In addition, since infrared light from the surface of the collecting jig 12 isotropically emitted, the arrangement is limited to the illustrated arrangement as long as the incident light of reflected light and stray light is suppressed to the light receiving element 9. Not.

  More preferably, the collection jig 12 has a configuration for collecting infrared light from the particles collected on the surface corresponding to the irradiation region 15 in the light receiving element 9. This configuration corresponds to, for example, a spherical recess 51 with reference to FIG. Furthermore, the collection jig 12 is preferably provided so as to be inclined by an angle θ in the direction toward the light receiving element 9 so that the surface of the collection jig 12 faces the light receiving element 9. With this configuration, there is an advantage that infrared light isotropically emitted from particles in the spherical recess 51 is reflected on the spherical surface and collected in the direction of the light receiving element 9, and there is an advantage that the received light signal can be increased. The size of the recess 51 is not limited, but is preferably larger than the irradiation region 15.

  Referring again to FIG. 2, the light receiving element 9 is connected to the signal processing unit 30 and outputs a current signal proportional to the amount of received light to the signal processing unit 30. Therefore, infrared light emitted from the light-emitting element 6 by irradiating light from the light-emitting element 6 to the particle floating in the introduced air and collected on the surface of the collecting jig 12 is received by the light-receiving element 9. Light is received, and the amount of received light is detected by the signal processing unit 30.

  Further, shutters 16A and 16B are installed in the introduction hole 10 and the discharge hole 11 of the case 5, respectively. The shutters 16A and 16B are connected to the measuring unit 40, and the opening and closing thereof are controlled. By closing the shutters 16A and 16B, the inflow of air into the case 5 and the incidence of external light are blocked. The measurement unit 40 closes the shutters 16A and 16B during infrared light measurement, which will be described later, and blocks the inflow of air into the case 5 and the entrance of external light. Thereby, the collection of suspended particles by the collection mechanism is interrupted at the time of infrared light measurement. Also, stray light in the case 5 can be suppressed by blocking external light from entering the case 5 during infrared light measurement. Note that either one of the shutters 16A and 16B, for example, at least the shutter 16B of the discharge hole 11 may be provided.

  The signal processing unit 30 is connected to the measurement unit 40 and outputs the result of processing the current signal to the measurement unit 40. Based on the processing result from the signal processing unit 30, the measuring unit 40 performs processing for displaying the measurement result on the display panel 130.

Here, the detection principle in the microorganism detection apparatus 100A will be described.
Jurgen Baier et al's “Journal of Investigative Dermatology” (Vol.127, P.1498-P.1506 (2007)) “Direct Detection of Singlet Oxygen Generated by UVA Irradiation in Human Cells and Skin” In addition, when the living tissue is irradiated with ultraviolet light or blue light in a wavelength range of 300 nm to 450 nm, oxygen contained in lipids and the like is excited to a singlet state through flavin, NADH, and a certain sterol compound in the tissue, It is known to emit infrared light having a peak near 1270 nm when it returns to the ground state. This phenomenon does not occur with dust or the like. The inventors conducted experiments as follows and found that microorganisms can be detected using this principle.

  In this experiment, as shown in FIG. 4, the collection mechanism and the air introduction mechanism 50 are removed from the configuration of FIG. 2, and the filter 14, the condenser lens 13, and the light receiving element 9 are replaced with the outside of the opening 72. An apparatus equipped with a spectroscope 71 was used. The inventors used a light emitting element 6 (emission peak wavelength: 365 nm and 405 nm) that is an ultraviolet LED provided on the upper surface of the collecting jig 12 before and after attaching yeast as microorganisms to the surface of the collecting jig 12. Then, each was irradiated with ultraviolet light to the yeast, light emitted from the yeast was introduced into the spectroscope 71 through the opening 72, and the spectrum was measured before and after the attachment of the microorganism.

  Before attachment of the yeast and before irradiation with ultraviolet light, the infrared light spectrum 64 shown in FIG. 5 is measured, and after attachment of the yeast and after irradiation with ultraviolet light, shown in FIG. An infrared light spectrum 65 was measured, and after the yeast was attached and irradiated with ultraviolet light, an infrared light spectrum 61 shown in FIG. 6 was measured.

  The infrared light spectrum 61 measured after yeast adhesion shown in FIG. 6 has a peak peculiar to microorganisms at about 1200 nm to about 1350 nm, more specifically around 1270 nm. On the other hand, both the infrared light spectrum 64 before the ultraviolet light irradiation and the infrared light spectrum 65 after the ultraviolet light irradiation measured from the surface of the collection jig 12 before the attachment of the yeast shown in FIG. A peak is not seen, and a large light amount difference is not seen only for a specific wavelength by comparing these. Therefore, from this measurement result, it can be determined that the light emission at the peak wavelength shown in FIG. 6 is caused by the microorganism (yeast). Therefore, it was verified that microorganisms can be detected by using this principle.

  In addition, in the infrared light spectrum 61 shown in FIG. 6, light emission appears in a wavelength region of 1400 nm or more in addition to the emission peak peculiar to microorganisms appearing from about 1200 nm to about 1350 nm. When the light receiving sensitivity characteristic of the light receiving element 9 is up to a wavelength range of 1400 nm or more, the configuration of FIG. Therefore, in order to solve this problem, it is preferable to use a band-pass filter that transmits only infrared light from about 1200 nm to about 1350 nm, for example, as the filter 14. If the sensitivity of the light receiving element is not in the wavelength range of 1400 nm or more, a short-cut filter that passes light of about 1200 nm or more may be used as the filter 14.

  A functional configuration of the microorganism detection apparatus 100A for detecting microorganisms in the air using the above principle will be described with reference to FIG. FIG. 7 shows an example in which the function of the signal processing unit 30 is realized by a hardware configuration that is mainly an electric circuit. However, at least a part of these functions may have a software configuration that is realized when the signal processing unit 30 includes a CPU (Central Processing Unit) (not shown) and the CPU executes a predetermined program. . In addition, an example in which the configuration of the measurement unit 40 is a software configuration is shown. However, at least some of these functions may be realized by a hardware configuration such as an electric circuit.

  Referring to FIG. 7, the signal processing unit 30 includes a current-voltage conversion circuit 34 connected to the light receiving element 9 and an amplification circuit 35 connected to the current-voltage conversion circuit 34.

  The measurement unit 40 includes a control unit 41, a storage unit 42, and a clock generation unit 43. Further, the measurement unit 40 executes an input unit 44 for receiving an input of information by receiving an input signal from the switch 110 in accordance with the operation of the switch 110, and a process of displaying a measurement result or the like on the display panel 130. For driving the display unit 45 and the external connection unit 46 for performing processing necessary for data exchange with an external device connected to the communication unit 150, and for driving the shutters 16A and 16B and the air introduction mechanism 50. Drive unit 48.

  Infrared light emitted from the particles in the irradiation region 15 is collected in the light receiving element 9 by irradiating the particles introduced into the case 5 and collected on the collecting jig 12 from the light emitting element 6. Lighted. A current signal corresponding to the amount of received light is output from the light receiving element 9 to the signal processing unit 30. The current signal is input to the current-voltage conversion circuit 34.

  The current-voltage conversion circuit 34 detects a peak current value H representing the intensity of infrared light from the current signal input from the light receiving element 9 and converts it into a voltage value Eh. The voltage value Eh is amplified to a preset amplification factor by the amplifier circuit 35 and is output to the measurement unit 40. The control unit 41 of the measurement unit 40 receives the input of the voltage value Eh from the signal processing unit 30 and sequentially stores it in the storage unit 42.

  The clock generation unit 43 generates a clock signal and outputs it to the control unit 41. The control unit 41 outputs a control signal for opening and closing the shutters 16A and 16B to the driving unit 48 at a timing based on the clock signal, and controls the opening and closing of the shutters 16A and 16B. Moreover, the control part 41 is electrically connected with the light emitting element 6 and the light receiving element 9, and controls those ON / OFF.

  The control unit 41 includes a calculation unit 411. In the calculation unit 411, calculation for calculating the amount of particles derived from living organisms in the introduced air is performed using the voltage value Eh stored in the storage unit. A specific calculation method will be described with reference to a time chart showing a control flow in the control unit 41 of FIG. Here, the concentration of microorganisms in the air introduced into the case 5 is calculated as the amount of biological particles.

  Referring to FIG. 8, the control unit 41 of the measurement unit 40 outputs a control signal to the drive unit 48 when the microorganism detection device 100 </ b> A is turned on, and drives the air introduction mechanism 50. The control unit 41 outputs a control signal for opening (turning on) the shutters 16A and 16B to the drive unit 48 at time T1 based on the clock signal from the clock generation unit 43. Thereafter, the control unit 41 outputs a control signal for closing (turning off) the shutters 16A and 16B to the drive unit 48 at time T2 after elapse of a predetermined collection time ΔT1 from time T1. .

  Thereby, the shutters 16A and 16B are opened from the time T1 to the collection time ΔT1, and external air is introduced into the case 5 through the introduction hole 10 by driving the air introduction mechanism 50. Particles in the air introduced into the case 5 are negatively charged by the discharge electrode 1, and due to the flow of air and the electric field formed between the discharge electrode 1 and the coating 3 on the surface of the collecting jig 12, It is collected on the surface of the collection jig 12 for the collection time ΔT1.

  At time T2, the shutters 16A and 16B are closed, and the air flow in the case 5 stops. Thereby, collection of the floating particles by the collection jig 12 is completed. This also blocks stray light from the outside.

  The control unit 41 outputs a control signal for causing the light receiving element 9 to start receiving light (ON) at time T2 when the shutters 16A and 16B are closed. Further, at the same time (time T2) or at time T3 slightly delayed from time T2, a control signal for starting (ON) light emission to the light emitting element 6 is output. Thereafter, at time T4 after elapse of a predetermined measurement time ΔT2 for measuring the infrared light intensity from the start of light emission at the light emitting element 6 (time T2 or time T3), the control unit 41 causes the light receiving element 9 to A control signal for terminating (OFF) light reception and a control signal for terminating (OFF) light emission to the light emitting element 6 are output. The measurement time ΔT2 may be set in advance in the control unit 41, or may be operated by operating the switch 110, a signal from the PC 300 connected to the communication unit 150 via the cable 400, or communication. It may be input or changed by a signal from a recording medium mounted on the unit 150. The same applies to the collection time ΔT1.

  Thereby, irradiation from the light emitting element 6 is started from time T3 (or time T2). The light from the light emitting element 6 is applied to the irradiation region 15 on the surface of the collecting jig 12, and infrared light is emitted from the collected particles. Infrared light for a measurement time ΔT2 from time T3 (or time T2) is received by the light receiving element 9, and a voltage value corresponding to the light quantity R is input to the measurement unit 40 and stored in the storage unit 42.

  At this time, the light received from the reflection region (not shown) where the particles on the surface of the collecting jig 12 are not collected, which is emitted from a light emitting element (not shown) such as an LED provided separately, is received. Light may be received by an element (not shown) and the ratio R / I0 may be stored in the storage unit 42 using the amount of received light as the reference value I0. By calculating the ratio with respect to the reference value I0, there is an advantage that the fluctuation of the infrared light amount caused by the fluctuation due to the environmental temperature or deterioration of the excitation light can be compensated.

  The amount of infrared light R measured at a specified time is related to the amount of biological particles (number of particles, particle concentration, etc.). The calculation unit 411 stores a correspondence relationship between the infrared light amount R (a voltage value corresponding to the infrared light amount R) and the biological particle amount (particle concentration) as illustrated in FIG. 9 in advance. Then, the calculation unit 411 calculates the biological particle concentration obtained by using the measured infrared light quantity R and the corresponding relationship from the biological biological substance in the air introduced into the case 5 during the time ΔT1. Calculated as particle concentration.

The correspondence relationship between the infrared light quantity R (voltage value corresponding to the infrared light amount R) and the concentration of biological particles is experimentally determined in advance. For example, in a 1 m ³ container, a microorganism such as Escherichia coli, Bacillus or mold is sprayed using a nebulizer, and the microorganism concentration is maintained at N / m ³ , thereby detecting a microorganism. Using 100A, microorganisms are collected during the collection time ΔT1 by the detection method described above. Then, the collected microorganisms are irradiated with light from the light emitting element 6, and the amount of infrared light R emitted during the measurement time ΔT2 is measured. The same measurement is performed for various microorganism concentrations, whereby the relationship between the infrared light amount R and the microorganism concentration (cells / m ³ ) shown in FIG. 9 is obtained.

  The correspondence relationship between the infrared light quantity R (voltage value corresponding to the infrared light amount R) and the biological particle concentration may be stored in the calculation unit 411 by being input by an operation of the switch 110 or the like. Alternatively, a recording medium in which the correspondence relationship is recorded may be loaded in the communication unit 150 and read by the external connection unit 46 and stored in the calculation unit 411. Alternatively, the calculation may be stored in the calculation unit 411 when the external connection unit 46 receives and transmits the data through the cable 400 that is input and transmitted by the PC 300 and connected to the communication unit 150. Alternatively, when the communication unit 150 performs infrared communication or Internet communication, the external connection unit 46 may receive data from another device through the communication performed by the communication unit 150 and may be stored in the calculation unit 411. Further, the correspondence relationship once stored in the calculation unit 411 may be updated by the measurement unit 40.

When the voltage value corresponding to the measured infrared light amount R is the voltage V1, the calculation unit 411 specifies the value corresponding to the voltage V1 from the correspondence relationship between the voltage value and the microorganism concentration in FIG. The derived particle concentration N1 (pieces / m ³ ) is calculated.

  However, the correspondence relationship between the infrared light amount R and the microorganism concentration differs depending on the type of microorganism (for example, the bacterial species). Therefore, the calculation unit 411 defines any one of the microorganisms as a standard microorganism and stores the correspondence between the infrared light amount R and the concentration of the microorganism. Thereby, the microorganism concentration in various environments is calculated as a microorganism concentration converted with reference to the standard microorganism. As a result, various environments can be compared, and environmental management becomes easy.

  In addition, as demonstrated using FIG. 6, light emission with the peak wavelength which appears in the measured infrared light spectrum is infrared light emitted from microorganisms. Therefore, when no peak is observed in the measured infrared light spectrum, there is a high possibility that microorganisms are not detected. Therefore, for example, when the microbe detection apparatus 100A includes a function for measuring a spectral spectrum as in the apparatus of FIG. 4, the calculation unit 411 determines the presence or absence of the peak of the measured infrared light spectrum, and the peak is If not, an error may be returned without performing the process of calculating the amount of microorganisms.

  The amount of living organism-derived particles introduced in the air, that is, the concentration of microorganisms, calculated by the calculation unit 411 is output from the control unit 41 to the display unit 45. The display unit 45 performs a process for causing the display panel 130 to display the input microorganism concentration. As an example of the display on the display panel 130, for example, a sensor display shown in FIG. Specifically, the display panel 130 is provided with a lamp for each density, and as shown in FIG. 10B, the display unit 45 identifies a lamp corresponding to the calculated density as a lamp to be lit, Turn on the lamp. As another example, the lamp may be lit in a different color for each calculated density. Further, the display panel 130 is not limited to the lamp display, and may display numbers or display a message prepared in advance corresponding to the density. The measurement result may be written to a recording medium attached to the communication unit 150 by the external connection unit 46 or may be transmitted to the PC 300 via the cable 400 connected to the communication unit 150.

  The input unit 44 may accept selection of a display method on the display panel 130 in accordance with an operation signal from the switch 110. Alternatively, the selection of whether the measurement result is displayed on the display panel 130 or output to an external device may be accepted. A signal indicating the content is output to the control unit 41, and a necessary control signal is output from the control unit 41 to the display unit 45 and / or the external connection unit 46.

  The inventors of the present invention have various concentrations on the surface of the collecting jig 12 using the apparatus shown in FIG. 4 with respect to the dependency of the microorganism concentration on the surface of the collecting jig 12 and the amount of infrared light from the surface. An experiment was conducted to confirm the amount of infrared light when the yeast was attached. As a result, it was confirmed that the yeast concentration and the measured infrared light amount have the relationship shown in FIG. In FIG. 11, the horizontal axis represents the number of yeasts per unit area. The vertical axis represents the integrated value of the amount of infrared light surrounded by the infrared light spectrum 61 and the baseline 62 measured after the attachment of the yeast shown in FIG. From the measurement result shown in FIG. 11, it was verified that the integrated value of the infrared light amount depends on the number N of yeasts per unit area on the surface of the collection jig 12.

  The microbial concentration on the surface of the collecting jig 12 depends on the concentration of biological particles in the air. Further, the integrated value of the infrared light amount surrounded by the infrared light spectrum 61 and the base line 62 corresponds to a voltage value corresponding to the infrared light amount. Therefore, it was verified from this experiment that the concentration of particles derived from living organisms in the air can be obtained using the correspondence relationship of FIG.

  As described above, the microorganism detection apparatus 100A uses the fact that infrared light is emitted from biological particles and infrared light is not emitted from other non-biological particles such as dust. Therefore, even if the introduced air contains particles other than biological particles such as dust, the biological particles can be accurately converted to other particles such as dust in real time. Can be detected separately. In addition, the detection can be performed with higher accuracy as compared with the conventional method of detecting particles derived from living organisms using fluorescence.

  Furthermore, in the microorganism detection apparatus 100A, the control shown in FIG. 8 is performed, so that the shutters 16A and 16B are closed to enter the case 5 when shifting from the collection process in the collection mechanism to the detection process in the detection mechanism. External light is blocked. As a result, stray light due to scattering by suspended particles during infrared light measurement can be suppressed, and measurement accuracy can be improved.

  In the microorganism detection apparatus 100A, repeated measurement can be performed by replacing the collection jig 12. In other words, the collection jig 12 can be regenerated and used by washing the dust that has been taken out and adsorbed. Alternatively, in a usage environment where there are many pathogenic bacteria or the like, the support substrate 4 may be made disposable by making it inexpensive such as a plastic material. Or, for example, as disclosed in Japanese Patent Application Laid-Open No. 2008-18406, after the measurement is completed, the surface of the collecting jig 12 is electrostatically reversed by reversing the polarities of the collecting jig 12 and the discharge electrode 1. Electrostatic repulsion occurs between the particles adsorbed on the surface of the collecting jig 12 and the surface of the collecting jig 12, and then the shutters 16A and 16B are opened to generate an air flow, thereby removing the particles adsorbed on the surface of the collecting jig 12. By doing so, the surface of the collecting jig 12 may be refreshed.

[Second Embodiment]
Referring to FIG. 12, the microorganism detection device 100B according to the second embodiment includes a case 5 provided with an introduction hole 10 and an exhaust hole, similar to the microorganism detection device 100A. 30 and the sensor mechanism 20 including the measurement unit 40 therein.

  In the microorganism detection apparatus 100B, the sensor mechanism 20 does not include the collection mechanism included in the microorganism detection apparatus 100A, and includes only the detection mechanism. In the detection mechanism of the microorganism detection apparatus 100B, the light emitting element 6 and the lens 7, and the light receiving element 9, the filter (or filter group) 14 and the condenser lens 13 are respectively converted into parallel light by the lens 7. The direction in which the light is received by the light receiving element 9 by being condensed by the condenser lens 13 is set at a predetermined angle. Furthermore, these are respectively configured such that the air moving in a flow path from the introduction hole 10 to the discharge hole is condensed by the irradiation region from the light emitting element 6 which is made parallel light by the lens 7 and the condenser lens 13. As a result, the light receiving element 9 is installed at an angle that passes through the region 55 of FIG. FIG. 12 shows an example in which these are installed so that the predetermined angle is about 60 degrees and the region 55 is in front of the introduction hole 10. The predetermined angle is not limited to 60 degrees, and may be another angle.

  Similar to the microorganism detection apparatus 100A according to the first embodiment, the filter 14 includes scattered light from particles in the fluid in the region 55, stray light due to light from the light emitting element 6, and microorganisms and fluorescent light emitting dust. That have optical characteristics such that the fluorescence emitted from the light does not enter the light receiving element 9 is used. Further, when the light receiving sensitivity characteristic of the light receiving element 9 is up to a wavelength range of 1400 nm or more, it is preferable that the filter 14 emits light other than infrared light that represents a light emission peak peculiar to microorganisms appearing from about 1200 nm to about 1350 nm. Those having optical characteristics that prevent light from entering the light receiving element 9 are used. As the filter 14 in this case, for example, a band-pass filter that transmits only infrared light from about 1200 nm to about 1350 nm is suitable. When the sensitivity of the light receiving element is not in the wavelength range of 1400 nm or more, a shortcut filter that allows light of about 1200 nm or more to pass through may be used as the filter 14.

  In the microorganism detection apparatus 100B, the light emitting element 6 is detected for particles floating in the air moving from the introduction hole 10 to the discharge hole and passing through the region 55 by the configuration of the detection mechanism shown in FIG. Infrared light emitted from the biological particles is received by the light receiving element 9. Since infrared light is generated when the particles cross the irradiation light from the light emitting element 6, a signal input to the signal processing unit 30 from the light receiving element 9 according to the amount of received light becomes a pulse.

  Referring to FIG. 13, the function of microorganism detection apparatus 100B for detecting microorganisms in the air is the same as the function configuration of microorganism detection apparatus 100A shown in FIG. Includes other configurations.

  In the microorganism detection apparatus 100B, the peak current value of the pulsed current signal from the light receiving element 9 is converted into a voltage value by the current-voltage conversion circuit 34 and amplified by the amplification circuit 35 at a predetermined amplification factor. The control unit 41 counts the number of input voltage values as the number of biological particles, and stores the result in the storage unit 42. The calculation unit 411 of the control unit 41 calculates the amount of particles (particle concentration) derived from living organisms in the introduced air using the count result stored in the storage unit 42.

A specific calculation method in the calculation unit 411 in the microorganism detection apparatus 100B will be described. It is assumed that N1 is stored as a count result of a predetermined time ΔT (min) while air is being introduced into the case 5 by the air introduction mechanism 50 at a flow velocity Wm ³ / min. At this time, air of the amount of W × ΔT (m ³ ) is introduced into the case 5 during the time ΔT. Therefore, N1 organism-derived particles exist in this air amount. From this, the calculation unit 411 calculates the biological particle concentration as N1 / (W × ΔT) (pieces / m ³ ). The number of particles and the particle concentration, which are the calculation results, are displayed on the display panel 130 by the display unit 45.

  One measurement time, that is, the time ΔT for introducing air into the case 5 and the flow rate W of the air introduction mechanism 50 may be set in advance in the control unit 41, or the operation of the switch 110 or the like. Alternatively, it may be input or changed by a signal from the PC 300 connected to the communication unit 150 via the cable 400, a signal from a recording medium attached to the communication unit 150, or the like.

  The microorganism detection apparatus 100B can also detect biological particles in a liquid as biological particles in a fluid. In that case, in addition to the configuration shown in FIG. 12, in addition to the configuration shown in FIG. 12, the microorganism detection apparatus 100B is configured to flow a liquid as disclosed in Japanese Patent Application Laid-Open No. 2006-177687 and Japanese Translation of PCT International Application No. 2008-508527. The flow path and the liquid sample cell are provided, for example, so that the cross section thereof is in the region 55, that is, through the introduction hole 10 and the discharge hole. The material of the channel and the cell to be provided is not limited to a specific material, but it is preferable to use a material that can efficiently irradiate particles in the liquid with ultraviolet light or blue light in a wavelength range of 300 nm to 450 nm. It is a material that can efficiently collect emitted infrared light on a light receiving element. More preferably, quartz is used.

With this configuration, if biological particles are present in the liquid passing through the region 55, infrared light emitted by irradiating the particles from the light emitting element 6 enters the light receiving element 9. The particles are detected. In this case, the calculation unit 411 calculates the particle concentration in the liquid using the flow velocity of the liquid in the flow path instead of the flow velocity Wm ³ / min by the air introduction mechanism 50 described above.

  The above-described detection method using the microorganism detection apparatus 100B is used when the concentration of biological particles in the fluid is small or when the flow velocity of the introduced fluid is small. This is a detection method under the condition that approximately one particle sequentially enters the irradiation region. Therefore, when the concentration of biological particles in the fluid is high or the flow velocity is high, that is, when a large number of particles enter the region 55, that is, the irradiation region of the light emitting element 6 at the same time, the following detection method is employed. .

That is, for example, a standard bacterium such as Bacillus or a specific fungus is previously sprayed to a predetermined concentration using a nebulizer in a case 5 having a predetermined volume (for example, 1 m ³ ), and the microorganism detection apparatus 100B is used. Then, the infrared light amount integrated for a predetermined time ΔT1 is measured. The same measurement is performed for various concentrations in the case 5 to obtain the correspondence shown in FIG. The correspondence is input by operating the switch 110, a signal from the PC 300 connected to the communication unit 150 via the cable 400, a signal from a recording medium attached to the communication unit 150, or the like. To the control unit 41.

  By setting in this way, the fluid to be measured is measured for time ΔT1 using the microorganism detection device 100B, and the correspondence relationship preset in the calculation unit 411 is referred to from the measured infrared light amount. Thus, the amount of biological particles, that is, the concentration of microorganisms can be calculated.

  Thus, in the microorganism detection apparatus 100B, the concentration of biological particles is derived by utilizing the fact that infrared light is emitted from biological particles and infrared light is not emitted from other particles such as dust. Therefore, even if the introduced air contains particles other than biological particles such as dust, the biological particles can be accurately converted to other particles such as dust in real time. Can be detected separately. In addition, the detection can be performed with higher accuracy as compared with the conventional method of detecting particles derived from living organisms using fluorescence.

  The microorganism detection device 100A or the microorganism detection device 100B can be used as an air cleaner as shown in FIG. 1 to manage and control the amount of microorganisms and dust in the environment where the air cleaner is installed. Can provide a healthy and safe life. Furthermore, as described above, since the measurement result can be displayed in real time in the microorganism detection apparatus 100A or the microorganism detection apparatus 100B, the measurer can grasp the measurement result in real time. As a result, it is possible to effectively manage and control the amount of microorganisms and dust in the environment.

  As another example, the microorganism detection device 100A or the microorganism detection device 100B can be used by being incorporated in the air purifier 200 as shown in FIG. In addition to an air purifier, it can also be incorporated into an air conditioner. Alternatively, as shown in FIG. 14B, the microorganism detection apparatus 100A or the microorganism detection apparatus 100B can be used alone.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  DESCRIPTION OF SYMBOLS 1 Discharge electrode, 2 High voltage power supply, 3 Film | membrane, 4 Support substrate, 5 Case, 6 Light emitting element, 7 Lens, 8 Aperture, 9 Light receiving element, 10 Introduction hole, 11 Outlet hole, 12 Collection jig, 13 Condensing lens , 14 filter, 15 irradiation region, 16A, 16B shutter, 20 sensor mechanism, 30 signal processing unit, 34 current-voltage conversion circuit, 35 amplification circuit, 40 measurement unit, 41 control unit, 42 storage unit, 43 clock generation unit, 44 input unit, 45 display unit, 46 external connection unit, 48 drive unit, 50 air introduction mechanism, 51 depression, 55 region, 61, 64, 65 infrared spectrum, 62 baseline, 71 spectrometer, 72 aperture, 100A, 100B Microbe detection device, 110 switch, 130 display panel, 150 communication unit, 300 PC, 400 cable, 4 11 Calculation part.

Claims (18)

A light emitting element;
A light receiving element for receiving infrared light;
Control means for controlling at least light emission by the light emitting element and light reception by the light receiving element;
Of the particles in the introduced fluid based on the infrared light from the particles in the introduced fluid received by the light receiving element by irradiating the introduced fluid with the light emitting element A microorganism detecting device comprising: a calculating means for calculating the amount of particles derived from the organism. A collecting jig for collecting particles in the introduced fluid;
The light emitting element is provided with an irradiation direction as a direction toward the collection jig,
The calculating means includes an infrared light amount from the particles collected on the collecting jig received by the light receiving element by being irradiated with the light emitting element on the collecting jig, and The microorganism detection apparatus according to claim 1, wherein the microorganism-derived particle amount of the particles in the introduced fluid is calculated based on the relationship between the stored infrared light amount and the organism-derived particle amount.   The microorganism detection apparatus according to claim 2, wherein the collection jig is replaceable.   The microorganism detection apparatus according to claim 2, further comprising means for removing particles collected by the collection jig.   The microorganism detection apparatus according to any one of claims 2 to 4, further comprising an input means for inputting an instruction to change a relationship between the infrared light amount and the amount of biological particles. The control means further controls introduction of the fluid,
A first control for introducing the fluid and collecting particles in the fluid with the collection jig;
After the first control, start light reception by the light receiving element, start light emission by the light emitting element after the start of the light reception, and after a predetermined measurement time from the start of light emission by the light emitting element, The microorganism detection apparatus according to claim 2, wherein a second control for terminating light reception by the light receiving element is performed.   The microorganism detection apparatus according to claim 6, wherein the control unit terminates the introduction of the fluid after a predetermined collection time has elapsed from the start of the introduction of the fluid in the first control. An introduction means for introducing the fluid at a predetermined flow rate;
The light emitting element is provided as a direction intersecting the flow path of the fluid introduced by the introduction means with the irradiation direction,
The calculation unit is configured to emit infrared light from particles in the introduced fluid that crosses irradiation from the light emitting element at the light receiving element by irradiating the light path with the light emitting element. The microorganism detection apparatus according to claim 1, wherein the amount of living organism-derived particles among the particles in the introduced fluid is calculated based on the number of received light beams and the flow velocity.   The microorganism detecting apparatus according to claim 8, wherein the calculating means counts the number of times a pulse signal is received according to the amount of infrared light received from the light receiving element.   The microorganism detection apparatus according to claim 1, further comprising a filter for suppressing light having a wavelength from the light emitting element and fluorescence from the biological particles to the light receiving element.   The microorganism detection apparatus according to any one of claims 1 to 10, further comprising display means for displaying a calculation result of the calculation means as a measurement result.   The microbe detection apparatus according to claim 1, wherein the light emitting element irradiates light in a wavelength range from ultraviolet to blue.   The microorganism detection apparatus according to claim 12, wherein the light emitting element irradiates light having a wavelength in a range of 190 nm to 450 nm. A light emitting element;
A light receiving element for receiving infrared light;
A microorganism detection apparatus, comprising: a microorganism detection apparatus comprising a calculation means for calculating the amount of biological particles contained in an introduced fluid,
Receiving, from the light receiving element, a signal corresponding to the amount of infrared light received from the particles in the introduced fluid irradiated by the light emitting element;
Calculating the amount of biologically-derived particles among the particles in the introduced fluid using the signal. The microorganism detection apparatus further includes a collection jig for collecting particles in the introduced fluid,
The light emitting element is provided with an irradiation direction as a direction toward the collection jig,
In the step of receiving the signal, the amount of infrared light from the particles collected on the collecting jig received by the light receiving element by irradiating the collecting jig with the light emitting element is increased. Receive the corresponding signal,
In the step of calculating the amount of biologically derived particles, the infrared light amount and, of the particles in the introduced fluid based on the relationship between the infrared light amount stored in advance and the biologically derived particle amount, The detection method according to claim 14, wherein the amount of biological particles is calculated. Before the step of receiving the signal, the step of introducing the fluid into the microorganism detection apparatus, and collecting particles in the fluid with the collection jig,
The step of receiving the signal starts light reception by the light receiving element after the introduction of the fluid, starts light emission by the light emitting element after the start of light reception, and starts the light emission from the light emitting element. The detection method according to claim 14, further comprising a step of controlling the light receiving element and the light emitting element so that the light reception by the light receiving element is terminated after the measurement time. In the step of collecting particles in the fluid with the collection jig, after the passage of a predetermined collection time from the start of introduction of the fluid, the introduction of the fluid is terminated,
The detection method according to claim 16, wherein in the step of controlling the light receiving element and the light emitting element, light reception by the light receiving element is started after completion of introduction of the fluid. The light emitting element is provided with the irradiation direction as a direction intersecting the flow path of the fluid to be introduced,
In the step of receiving the signal, from the particles in the fluid introduced at a predetermined flow velocity in the flow path across the irradiation from the light emitting element by irradiating the light path with the light emitting element. Receive a signal according to the amount of infrared light,
In the step of calculating the biological particle amount, the biological particle amount of the particles in the introduced fluid is calculated based on the number of reception times per unit time of the signal and the flow velocity. The detection method according to claim 14.

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