JP2016212061A - Dust detection device and dust detection system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress an increase in maintenance time and besides to suppress deterioration in detection accuracy of a dust sensor.SOLUTION: A dust detection device 1 comprises a housing 2, a collection body 3, and a dust sensor 4. The dust sensor 4 includes a sensor body 41 having a through-path 44 for dust collected by the collection body 3 to pass through, a light emission section 42 for emitting light toward the through-path 44, and a light reception section 43 configured to receive the light emitted by the light emission section 42 and reflected by dust passing through the through-path 44. The dust detection device 1 further comprises an air blow mechanism 5 configured to jet air supplied from an air supply source into the sensor body 41.SELECTED DRAWING: Figure 1

Description

  The present invention generally relates to a dust detection device and a dust detection system, and more particularly to a dust detection device and a dust detection system for detecting dust contained in sample air.

  Conventionally, for example, a dust detection device described in Patent Document 1 is known as a dust detection device that detects dust (see, for example, Patent Document 1). The dust detection apparatus described in Patent Document 1 collects dust contained in sample air introduced from an inlet through a collector, and the dust collected by the collector passes through the center body of the dust sensor. Is configured to do. And when the said dust passes the inside of a sensor main body, a dust sensor is comprised so that dust may be detected using a light emission part and a light-receiving part.

JP2013-257218A

  However, in the conventional dust detection device described in Patent Document 1, dust collected by the collector may stay in the sensor body of the dust sensor due to adhesion or the like. For this reason, the conventional dust detection device has a problem that the detection accuracy of the dust sensor decreases due to dust staying in the sensor body of the dust sensor.

  In order to remove dust staying in the sensor body, it is conceivable to disassemble and clean the sensor body. However, disassembling and cleaning the sensor body has a new problem that maintenance time increases.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a dust detection device and a dust detection system that can suppress a decrease in detection accuracy of a dust sensor while suppressing an increase in maintenance time. It is to provide.

  The dust detection device of the present invention includes a housing having an inlet for introducing sample air and an outlet for discharging the sample air, and the sample air housed in the housing and introduced from the inlet. A collector that collects dust contained therein; and a dust sensor that is housed in the housing and detects the dust collected by the collector. The dust sensor includes a sensor body having a through-passage through which the dust collected by the collector passes, a light emitting unit that is housed in the sensor body and emits light toward the through-passage, and the sensor body And a light receiving portion that receives light reflected from the dust emitted from the light emitting portion and passing through the through passage. The dust detection device further includes an air blow mechanism that injects air supplied from an air supply source into the sensor body.

  In this dust detection apparatus, it is preferable that the air blow mechanism injects the air toward the light receiving unit from a position facing the light receiving unit in the sensor body.

  In this dust detection apparatus, it is preferable that the air blow mechanism injects the air toward the light emitting unit from a position facing the light emitting unit in the sensor body.

  In this dust detection device, the air blow mechanism is provided in the sensor body, and has a nozzle having an ejection port through which the air is ejected, and is provided outside the sensor body and allows the air from the air supply source to pass through. A joint for communicating the passage tube and the nozzle, and the dust sensor further includes a reinforcing mechanism provided to contact one outer wall of the sensor body, and the joint is attached to the reinforcing mechanism. It is preferable that

  The dust detection device preferably further includes an exhaust fan that discharges the sample air from the inside of the housing to the outside of the housing.

  In this dust detection apparatus, the collection body has an opening area of the first opening end facing the introduction port that is equal to or larger than the opening area of the introduction port, and the second opening end facing the through path. The opening area of the through passage is preferably smaller than the opening area of the introduction port and the opening area of the discharge port.

  The dust detection system of this invention is equipped with the said dust detection apparatus and the processing apparatus which calculates | requires the quantity of the said dust based on the light reception amount of the said light-receiving part.

  The dust detection system preferably further includes the air supply source.

  In this dust detection system, it is preferable that the processing device controls the air supply source so as to inject the air into the sensor body when the amount of the dust is equal to or greater than a threshold value.

  In this dust detection system, the processing device injects the air into the sensor body when the amount of the dust is not less than the threshold value when the sample air is not introduced into the housing. It is preferable to control the air supply source.

  In this invention, the fall of the detection accuracy of a dust sensor can be suppressed, suppressing the increase in maintenance time.

It is typical sectional drawing of the dust detection apparatus which concerns on Embodiment 1. FIG. It is typical sectional drawing of the dust detection apparatus which concerns on Embodiment 1. FIG. In the dust detection apparatus which concerns on Embodiment 1, it is sectional drawing of an AA line. It is a perspective view of the principal part of the dust detection apparatus which concerns on Embodiment 1. FIG. It is an external view of the principal part of the dust sensor and air blow mechanism which concern on Embodiment 1. FIG. It is an external view of the adhesion member and plate which concern on Embodiment 1. FIG. 7A and 7B are explanatory views of the operation of the air blow mechanism according to the first embodiment. 8A and 8B are explanatory views of the operation of the air blow mechanism according to the first embodiment. 9A and 9B are explanatory views of the operation of the air blow mechanism according to the first embodiment. 1 is a configuration diagram of a dust detection system according to Embodiment 1. FIG. It is an external view of the principal part of the dust detection apparatus which concerns on the modification of Embodiment 1. It is typical sectional drawing of the dust detection apparatus which concerns on the other modification of Embodiment 1. It is typical sectional drawing of the dust detection apparatus which concerns on the further another modification of Embodiment 1. FIG. It is an external view of the dust detection apparatus which concerns on Embodiment 2. FIG. It is typical sectional drawing of the dust detection apparatus which concerns on Embodiment 2. FIG. It is typical sectional drawing of the dust detection apparatus which concerns on the modification of Embodiment 2.

  Hereinafter, the details of the dust detection device and the dust detection system according to the first and second embodiments will be described with reference to the drawings.

(Embodiment 1)
1-4, the dust detection apparatus 1 which concerns on Embodiment 1 has the housing | casing 2, the collection body 3, the dust sensor 4, the air blow mechanism 5, the flow velocity sensor 6, and the adhesion member 7, as shown in FIGS. I have. In the following description, however, the vertical and horizontal directions are defined in FIG. 1, the horizontal direction in FIG. 1 is defined as the front-rear direction, and the direction perpendicular to the paper surface of FIG.

  The housing 2 has an inlet 28 through which the sample air 91 is introduced and an outlet 29 through which the sample air 91 is discharged. The housing 2 has a substantially rectangular shape, and includes a body 21 and a cover 22. The body 21 is made of metal or synthetic resin. The cover 22 is made of metal or synthetic resin and covers the opening of the body 21.

  The body 21 includes a bottom 23, a first wall 24, a second wall 25, a first hose 26, and a second hose 27. The bottom portion 23, the first wall portion 24, and the second wall portion 25 are all plate-like and are provided integrally. Each of the bottom portion 23, the first wall portion 24, and the second wall portion 25 may be a synthetic resin plate material having a light shielding property. In this case, the bottom 23, the first wall 24, and the second wall 25 are joined with an adhesive or the like to form the body 21.

  A circular introduction port 28 is opened at the center of the first wall portion 24. A circular discharge port 29 is opened at the center of the second wall portion 25. The first hose 26 is formed in a cylindrical shape from metal or synthetic resin, and is inserted through the introduction port 28. The first hose 26 serves as an inflow path for the sample air 91. The second hose 27 is formed in a cylindrical shape from metal or synthetic resin, and is attached to the second wall portion 25 of the body 21 so that the passage of the second hose 27 communicates with the discharge port 29. Yes. The second hose 27 serves as an outflow path for the sample air 91.

  The collection body 3 is accommodated in the housing 2 and is configured to collect dust contained in the sample air 91 introduced from the introduction port 28. The collector 3 is formed in a cone shape from a metal or a synthetic resin, and has a circular first opening end 31 and a circular second opening end 32. That is, the collection body 3 is formed so that the area of the cross section parallel to the opening surface of the first opening end 31 decreases as the first opening end 31 approaches the second opening end 32. The first opening end 31 faces the introduction port 28 (opening portion of the first hose 26). The second open end 32 faces the through path 44 of the dust sensor 4. More specifically, in the collector 3, the first opening end 31 faces the introduction port 28 (first hose 26) at a predetermined distance, and the second opening end 32 is a through path of the sensor body 41. 44 is disposed in the housing 2 so as to face the housing 44. A gap (space) serving as a flow path for flowing the sample air 91 is formed between the housing 2 and the collector 3.

  The collector 3 is formed such that the opening area (inner diameter R1) of the first opening end 31 is equal to or larger than the opening area (inner diameter R2) of the introduction port 28 (first hose 26) (R1 ≧ R2). . The collector 3 is formed such that the opening area of the first opening end 31 is larger than the opening area (inner diameter R3) of the second opening end 32 (R1> R3). Furthermore, the collector 3 is formed so that the opening area of the second opening end 32 is equal to or larger than the opening area (diameter R4) of the through-passage 44 of the dust sensor 4 (R3 ≧ R4). The ratio of the opening area of the first opening end 31 and the opening area of the introduction port 28 is not limited to the ratio in the illustrated example. If the opening area of the first opening end 31 is equal to or larger than the opening area of the introduction port 28 (R1 ≧ R2), what is the ratio between the opening area of the first opening end 31 and the opening area of the introduction port 28? It may be a ratio. The ratio of the opening area of the first opening end 31 and the opening area of the second opening end 32 is not limited to the ratio in the illustrated example. If the opening area of the first opening end 31 is larger than the opening area of the second opening end 32 (R1> R3), the opening area of the first opening end 31 and the opening area of the second opening end 32 are The ratio may be any ratio. The ratio between the opening area of the second opening end 32 and the opening area of the through passage 44 is not limited to the ratio in the illustrated example. If the opening area of the second opening end 32 is equal to or larger than the opening area of the through passage 44 (R3 ≧ R4), what is the ratio between the opening area of the second opening end 32 and the opening area of the through passage 44? It may be a ratio.

  The dust sensor 4 is housed in the housing 2 and is configured to detect dust collected by the collector 3. That is, the dust sensor 4 is configured to detect dust contained in the sample air 91. The dust sensor 4 is, for example, a photoelectric sensor. As shown in FIG. 3, the dust sensor 4 includes a sensor main body 41, a light emitting unit 42, and a light receiving unit 43.

  The sensor body 41 is formed in a rectangular box shape with a synthetic resin having a light shielding property. The sensor body 41 includes a front plate 411 (see FIG. 7B) provided on the inflow side and a back plate 412 (see FIG. 7B) provided on the outflow side. The front plate 411 has a first passage hole 441 (see FIG. 7B) through which the sample air 91 passes. The back plate 412 has a second passage hole 442 (see FIG. 7B) through which the sample air 91 passes.

  The sensor body 41 has a cylindrical through passage 44 formed between the first passage hole 441 and the second passage hole 442. The through passage 44 is formed at the approximate center of the sensor body 41. The through passage 44 faces the collection body 3 and the adhesive member 7. The sample air 91 is introduced into the sensor body 41 from the first passage hole 441 and is discharged out of the sensor body 41 from the second passage hole 442. That is, the dust 92 collected by the collecting body 3 passes through the through passage 44.

  The sensor body 41 has a connection port 451 and a connection port 452 as shown in FIG. 7A. The connection port 451 has a round shape and is provided below the through passage 44 in the sensor body 41. A joint 54 described later is connected to the connection port 451. The connection port 452 has a round shape and is provided below the through passage 44 in the sensor body 41. A joint 57 described later is connected to the connection port 452.

  The opening area of the through passage 44 is smaller than the opening area of the introduction port 28 and the opening area of the discharge port 29. That is, the opening areas of the first passage hole 441 and the second passage hole 442 are smaller than the opening area of the introduction port 28 and the opening area of the discharge port 29.

  The light emitting unit 42 is accommodated in the sensor main body 41 and configured to emit light toward the through path 44. The light emitting unit 42 is provided above the through passage 44 in the sensor main body 41. The light emitting unit 42 includes a light emitting element that emits light, a drive circuit that drives the light emitting element, and a lens that converts light emitted from the light emitting element into parallel light. The light emitting element is, for example, a light emitting diode. The light emitting unit 42 irradiates the through passage 44 with parallel light. That is, the light emitting unit 42 irradiates the sample air introduced from the first passage hole 441 and passing through the sensor body 41 with parallel light.

  The light receiving unit 43 is housed in the sensor main body 41 and is configured to receive light emitted from the light emitting unit 42 and reflected by dust passing through the through path 44. More specifically, the light receiving portion 43 is provided above the through passage 44 in the sensor main body 41. The light receiving unit 43 includes a lens that collects light reflected by dust passing through the through passage 44 in the light receiving element, a light receiving element that receives the light, and an amplifier that amplifies the output signal of the light receiving element. The light receiving element is, for example, a photodiode or a phototransistor. The light receiving unit 43 receives the light reflected by the dust contained in the sample air 91. Of the light emitted from the light emitting unit 42, the light that is not reflected by the dust 92 crosses the through path 44 and is not received by the light receiving unit 43.

  As shown in FIGS. 1 and 4, the dust detection device 1 includes a support 11 for supporting the collector 3 and the dust sensor 4 on the housing 2. The support 11 is made of metal or synthetic resin. The support 11 is attached to the body 21 of the housing 2. In the support 11, the central axis of the inlet port 28 and the outlet port 29, the central axis of the collector 3, and the central axis of the through-passage 44 of the dust sensor 4 are arranged on a substantially straight line (a chain line in FIG. 1). Further, the collector 3 and the dust sensor 4 are supported in the housing 2. In addition, the support tool 11 can adjust the attachment position of the support tool 11 with respect to the body 21 in the front-back direction (left-right direction of FIG. 1), and is between the 1st hose 26 and the 1st opening end 31 of the collector 3. It is preferable that the distance can be adjusted.

  The air blow mechanism 5 is connected to an air supply source 82 (see FIG. 10), and is configured to inject air 83 supplied from the air supply source 82 into the sensor main body 41. As shown in FIGS. 3 to 5, the air blow mechanism 5 includes a first air blow mechanism 51 and a second air blow mechanism 52. The air 83 is a clean air that does not contain dust or the like (at least does not include dust to be detected). The air 83 preferably has the same component ratio as the atmosphere. However, the air 83 is not limited to the same component ratio as the atmosphere, and may include an appropriate gas component.

  As shown in FIG. 7A, the first air blow mechanism 51 is configured to inject air 83 toward the light receiving unit 43 from a position facing the light receiving unit 43 in the sensor main body 41. That is, the first air blow mechanism 51 is configured to release the high-pressure air 83 toward the light receiving unit 43.

  The first air blow mechanism 51 includes a nozzle 53 and a joint 54. The nozzle 53 is provided in the sensor main body 41. More specifically, the nozzle 53 is provided in the sensor main body 41 at a position facing the light receiving surface of the light receiving unit 43. The nozzle 53 has an injection port 531 through which the air 83 is injected. The joint 54 is provided outside the sensor main body 41 and communicates the nozzle 53 and the passage pipe 55. That is, the joint 54 is attached to the connection port 451 in order to connect the nozzle 53 and the passage pipe 55. The passage pipe 55 is a tube, for example, and the air 83 from the air supply source 82 passes through the passage pipe 55. That is, the air 83 from the air supply source 82 is jetted from the nozzle 53 toward the light receiving unit 43 through the passage pipe 55 and the joint 54.

  The second air blow mechanism 52 is configured to inject air 83 toward the light emitting unit 42 from a position facing the light emitting unit 42 in the sensor body 41. That is, the second air blow mechanism 52 is configured to discharge the high-pressure air 83 toward the light emitting unit 42.

  The second air blow mechanism 52 includes a nozzle 56 and a joint 57. The nozzle 56 is provided in the sensor main body 41. More specifically, the nozzle 56 is provided in the sensor main body 41 at a position facing the light emitting surface of the light emitting unit 42. The nozzle 56 has an injection port 561 through which the air 83 is injected. The joint 57 is provided outside the sensor main body 41 and communicates the nozzle 56 and the passage pipe 58. That is, the joint 57 is attached to the connection port 452 in order to connect the nozzle 56 and the passage pipe 58. The passage pipe 58 is a tube, for example, and the air 83 from the air supply source 82 passes therethrough. That is, the air 83 from the air supply source 82 is jetted from the nozzle 56 toward the light emitting unit 42 through the passage pipe 58 and the joint 57.

  The flow velocity sensor 6 shown in FIGS. 1 to 4 is configured to measure the flow velocity of the sample air 91. The flow velocity sensor 6 of the present embodiment is provided between the dust sensor 4 and the discharge port 29 in the housing 2. More specifically, the flow velocity sensor 6 is attached to the downstream side of the sensor body 41 and in the vicinity of the inlet of the discharge port 29.

  Since the turbulent flow of the sample air 91 is generated in the vicinity of the introduction port 28, the flow velocity of the sample air 91 varies greatly. For this reason, the flow velocity of the sample air 91 cannot be accurately measured. Therefore, the flow velocity sensor 6 is preferably arranged at a position where the sample air 91 is not a turbulent flow but a laminar flow. Therefore, the flow velocity sensor 6 of the present embodiment is attached near the entrance of the discharge port 29. The flow velocity sensor 6 is not limited to being disposed in the vicinity of the inlet of the discharge port 29, but may be disposed at a position where the sample air 91 is not a turbulent flow but a laminar flow. For example, the flow rate sensor 6 may be attached to the first hose 26 or may be attached to the second hose 27.

  By the way, the measurement result of the flow velocity sensor 6 is used when determining the detection cycle of the dust sensor 4. The dust sensor 4 passes through the through passage 44 at a detection cycle T2 shorter than the time T1 (= L1 / V1) obtained by dividing the length L1 of the through passage 44 by the flow velocity V1 measured by the flow velocity sensor 6. To detect dust. For example, when the length L1 of the through passage 44 is 20 mm and the flow velocity V1 measured by the flow velocity sensor 6 is 20 m / s, the time T1 is 1 ms. Therefore, the detection cycle T2 may be 0.5 ms, for example.

  The adhesive member 7 is configured to collect dust 92 that passes through the through passage 44. The adhesive member 7 is in the form of a film and has an adhesive surface 701 (see FIG. 6B). The adhesive member 7 is provided between the through passage 44 and the discharge port 29 at a position where the adhesive surface 701 faces the opening surface (second passage hole 442) of the through passage 44.

  In the present embodiment, the distance D <b> 1 between the adhesive member 7 and the dust sensor 4 is not more than three times the diameter R <b> 4 of the through passage 44. That is, the adhesive member 7 is provided at a position such that the distance D1 between the adhesive member 7 and the dust sensor 4 is not more than three times the diameter R4 of the through passage 44 by the following plate 71 and guide member 46. Yes.

  As shown in FIGS. 6A and 6B, the dust detection device 1 includes a plate 71 having an opening 713 as a support mechanism that supports the adhesive member 7. The plate 71 is inserted into the mounting hole 201 (see FIGS. 1 and 2) of the housing 2 and guided by the guide member 46 of the dust sensor 4.

  The plate 71 is formed in a plate shape with synthetic resin or metal. The plate 71 is integrally provided with a main body 711 and a tip 712. The main body 711 includes a round hole opening 713 and a plurality (four in the illustrated example) of long through holes 714. The opening 713 is an opening for collecting dust and is covered with the adhesive member 7. That is, the adhesive member 7 is attached to the plate 71 such that the adhesive surface 701 faces the through path 44 and covers the opening 713. Each through hole 714 is a through path for sample air, and the sample air 91 passes through each through hole 714.

  As shown in FIG. 1, the dust sensor 4 includes a guide member 46 that guides the plate 71. The guide member 46 is made of metal or synthetic resin. The guide member 46 is attached so as to contact the sensor main body 41. The guide member 46 has two grooves 461. Each groove 461 has substantially the same shape as the cross-sectional shape in the longitudinal direction of the main body 711 of the plate 71. A plate 71 is inserted into each groove 461. Thus, the guide member 46 guides the plate 71 to a position where the opening 713 of the plate 71, that is, the adhesive member 7 faces the opening surface of the through path 44.

  Further, the housing 2 has an attachment hole 201 for attaching the plate 71. More specifically, the attachment hole 201 is formed at a position facing the bottom 23 of the body 21 in the cover 22. When collecting the dust 92 using the adhesive member 7, a plate 71 is inserted into the mounting hole 201 as shown in FIG. 1. Thereby, the adhesive member 7 attached to the plate 71 can be arranged in the housing 2 without disassembling the housing 2. On the other hand, when the dust 92 is not collected, the guide member 46 may be removed from the sensor body 41 and the attachment hole 201 may be closed with the lid member 202 as shown in FIG.

  Next, the operation of the dust detection apparatus 1 according to the present embodiment will be described with reference to FIG. The sample air 91 is introduced into the housing 2 through the first hose 26 inserted into the introduction port 28. On the other hand, a dust collecting mechanism (such as a dust collector) is connected to the second hose 27 whose opening communicates with the discharge port 29, and the dust collecting mechanism sucks the sample air 91 through the second hose 27, thereby introducing the inlet port. A flow of sample air 91 from 28 to the discharge port 29 is generated.

  The sample air 91 that has flowed into the first hose 26 has its flow velocity abruptly reduced after exiting the first hose 26 into the housing 2. Therefore, a part of the sample air 91 whose flow velocity has decreased is discharged from the discharge port 29 (second hose 27) through the flow path between the collector 3 and the housing 2. On the other hand, the dust contained in the sample air 91 flows into the collection body 3 while maintaining the speed at which the first hose 26 has moved according to the law of inertia, and further passes through the through-passage 44 of the dust sensor 4. To do. However, a part of the dust does not travel directly from the first opening end 31 of the collector 3 to the through passage 44 but moves to the second opening end 32 after colliding with the inner peripheral surface of the collector 3. It will be. In addition, since the inner peripheral surface of the collection body 3 is an inclined surface inclined toward the through passage 44, the dust that collides with the inner peripheral surface of the collection body 3 can be smoothly guided to the through passage 44.

  Thereafter, the dust sensor 4 detects the dust collected by the collector 3. The dust that has passed through the through-passage 44 of the dust sensor 4 exits the through-passage 44 and adheres to the adhesive member 7. The flow rate sensor 6 measures the flow rate of the sample air 91. Thereafter, the sample air 91 is discharged out of the housing 2 through the discharge port 29.

  As described above, in the dust detection apparatus 1 according to the present embodiment, dust contained in the sample air 91 is collected by the collector 3 and detected by the dust sensor 4, and further, a part of the sample air 91 is obtained. It is discharged from the outlet 29 through the flow path outside the collector 3 without flowing into the collector 3. For this reason, the amount of sample air 91 (sample air 91 including dust 92) that passes through the through-passage 44 of the dust sensor 4 per unit time is greater than the amount of sample air 91 introduced per unit time from the inlet 28. Can also be reduced. As a result, in the dust detection apparatus 1 according to the present embodiment, even when the amount of the sample air 91 per unit time is large, a decrease in detection accuracy is suppressed, and even when the flow rate of the sample air 91 is high, the dust 92 can be obtained in a short time. Can be detected. In other words, even if the diameter of the through-passage 44 of the dust sensor 4 is small (for example, about 10 mm in diameter) and the amount of sample air 91 per unit time is large (the flow rate is fast), the decrease in detection accuracy is suppressed. The dust 92 can be detected in a short time.

  Next, the operation of the air blow mechanism 5 according to the present embodiment will be described with reference to FIGS.

  First, the operation of the first air blow mechanism 51 will be described. As shown in FIGS. 7A and 7B, the first air blow mechanism 51 injects air 83 from a nozzle 53 provided at a position facing the light receiving unit 43. As shown in FIGS. 8A and 8B, the dust 92 staying on the light receiving unit 43 due to adhesion or the like is blown off by the air 83. Thereafter, as shown in FIGS. 9A and 9B, the dust 92 blown off by the air 83 is discharged out of the sensor body 41 from the second passage hole 442 through the through passage 44.

  Next, the operation of the second air blow mechanism 52 will be described. The second air blow mechanism 52 is the same as the first air blow mechanism 51. First, the second air blow mechanism 52 injects air 83 from a nozzle 56 provided at a position facing the light emitting unit 42. The dust 92 staying on the light emitting unit 42 due to adhesion or the like is blown off by the air 83. Thereafter, the dust 92 blown off by the air 83 passes through the through passage 44 and is discharged out of the sensor body 41 from the second passage hole 442.

  Thus, when the dust 92 contained in the sample air 91 adheres to the light emitting part 42 and the light receiving part 43 of the dust sensor 4, the air blow mechanism 5 injects air 83 to the light emitting part 42 and adheres to the light emitting part 42. The dust 92 that has been discharged can be discharged out of the dust sensor 4, and the air 92 can be ejected to the light receiving portion 43 to discharge the dust 92 attached to the light receiving portion 43 to the outside of the dust sensor 4.

  Next, the dust detection system 8 according to the present embodiment will be described with reference to FIG.

  The dust detection system 8 includes a dust detection device 1, a processing device 81, and an air supply source 82.

  The processing device 81 includes a central processing unit and a computer (microcomputer) on which a memory is mounted as main components, and is configured to implement functions as a control unit, a calculation unit, and a flow rate control unit by executing a program. Has been.

  The processing device 81 is configured to control the drive circuit of the light emitting unit 42 of the dust sensor 4 as a function of the control unit. The processing device 81 controls the light emitting unit 42 to emit pulsed light by periodically driving the drive circuit of the light emitting unit 42. That is, the processing device 81 controls the light emitting unit 42 so as to emit light at the detection cycle T2.

  The processing device 81 is configured to determine the amount of dust (at least one of the number and concentration) based on the detection result of the dust sensor 4 (the amount of light received by the light receiving unit 43 of the dust sensor 4) as a function of the calculation unit. Yes. More specifically, the processing device 81 acquires a signal level corresponding to the amount of light received by the light receiving unit 43 from the detection result of the dust sensor 4. Then, the processing device 81 calculates the amount of dust based on the signal level.

  Here, the processing device 81 controls the dust sensor 4 so that the detection cycle T2 of the dust sensor 4 is shorter than the time T1 (the length L1 / the flow velocity V1 measured by the flow velocity sensor 6). . And the processing apparatus 81 detects the quantity of dust by counting the signal level more than a threshold level. For example, when dust having a wide range of mass is generated in a processing process or the like, the processing device 81 corresponds to a mass of a size that causes a failure from the causal relationship between the signal level obtained from the detection result of the dust sensor 4 and the failure. What is necessary is just to count the signal level more than a value (threshold level).

  The processing device 81 is configured to control the dust collection mechanism 85 as a function of the flow velocity control unit. More specifically, the processing device 81 controls the dust collection mechanism 85 so that the flow velocity measured by the flow velocity sensor 6 is within a predetermined range. That is, the processing device 81 is configured to control the dust collection mechanism 85 using the measurement result of the flow rate sensor 6 so as to ensure a flow rate of a certain value or more. The dust collection mechanism 85 is, for example, a dust collector or a dust collection system, and is a mechanism for moving the sample air 91.

  The processing device 81 is configured to notify the flow rate measured by the flow rate sensor 6 (the flow rate of the sample air 91) as a function of the notification unit. The processing device 81 may include a sound output unit such as a speaker, or may include a display unit such as a monitor.

  The processing device 81 is configured to issue an alarm when the flow velocity measured by the flow velocity sensor 6 is outside a predetermined range. The predetermined range may be a range greater than or equal to a predetermined value, or may be a predetermined value. Thereby, by monitoring the measurement result of the flow velocity sensor 6, the dust collection system can be controlled so that the flow velocity does not become less than a certain value. For example, the processing device 81 is configured to issue an alarm when the flow velocity measured by the flow velocity sensor 6 is less than a certain value. Thereby, it is possible to monitor that a flow velocity of a certain value or more is secured. Moreover, the user can adjust the dust collecting mechanism 85 by the warning.

  Next, a usage example of the dust detection system 8 according to the present embodiment will be described with reference to FIG. Specifically, the case where the dust detection system 8 is used in a product production line will be described. The dust detection system 8 detects dust adhering to the inspection object during manufacturing. The inspection object may be a finished product or an intermediate product that is in the middle of manufacturing.

  In the dust detection apparatus 1, a processing unit 84 that is a part of a production line is connected to the introduction port 28 side, and a dust collection mechanism 85 is connected to the discharge port 29 side. An injection mechanism that injects air onto the inspection object and a dust collection system that collects dust separated from the inspection object by the air from the injection mechanism are disposed at predetermined positions of the processing unit 84. The dust collection system includes a dust collection mechanism 85 for drawing the sample air 91 and a hose through which the sample air 91 passes from the processing unit 84 to the dust collection mechanism 85. And the dust detection apparatus 1 which concerns on this embodiment is connected to the middle of the hose in a dust collection system. That is, in the dust detection apparatus 1, the sample air 91 including dust that is separated from the inspection object is introduced from the introduction port 28 and is discharged from the discharge port 29 toward the dust collection mechanism 85.

  First, an injection mechanism injects air with respect to a test object. The dust adhering to the inspection object is separated from the inspection object by the air. The sample air 91 containing the dust separated from the inspection object is introduced into the dust detection device 1 through the hose.

  The dust detection device 1 detects dust contained in the sample air 91, and the processing device 81 obtains the amount of dust detected by the dust detection device 1. When the amount of dust is less than the predetermined value, the processing device 81 moves the belt conveyor of the production line. When the amount of dust is greater than or equal to a predetermined value, the processing device 81 controls the injection mechanism so as to inject air again onto the inspection object.

  By performing control according to the amount of dust as described above, the yield of inspection objects can be increased compared to the case where the injection mechanism injects air to all inspection objects for a certain period of time. For example, for an inspection object with a lot of dust, increase the number of times of injecting air to increase the air injection time, and for an inspection object with a small amount of dust, reduce the number of times of air injection. Air injection time can be shortened.

  Further, the processing device 81 receives the measurement result of the flow rate sensor 6 from the flow rate sensor 6. Then, the processing device 81 controls the dust collection system based on the measurement result of the flow rate sensor 6 so that the flow rate of the sample air 91 becomes a certain value or more.

  When a plurality of inspection objects continuously have a certain amount or more of dust, the processing device 81 may be configured to determine that a problem has occurred in the production line and to notify an alarm.

  The usage examples of the dust detection device 1 and the dust detection system 8 according to the present embodiment are not limited to the above, and may be applied to the following applications. The dust detection device 1 and the dust detection system 8 are used for manufacturing automobile parts, electronic devices, batteries, precision parts, food processing, detection of dust or dust generation in the natural environment and living environment, and confirmation of the degree of dust removal by air cleaning. be able to. Moreover, the dust detection apparatus 1 and the dust detection system 8 can be used for the detection of the environment in the air shower room before entering the manufacturing process site in the manufacture of automobile parts, electronic devices, batteries, precision parts, and food processing. Furthermore, the dust detection device 1 and the dust detection system 8 can be used for confirming a change in dust floating in the air in a natural environment, a living environment, a manufacturing environment, or the like.

  The dust detection device 1 according to the present embodiment described above injects air 83 into the sensor main body 41 of the dust sensor 4. Thereby, even if the dust 92 stays in the sensor main body 41 due to adhesion or the like, the dust 92 can be removed from the sensor main body 41. As a result, a decrease in detection accuracy of the dust sensor 4 can be suppressed. Further, by realizing self-cleaning in which the air 83 is injected into the sensor main body 41 to remove the dust 92, it is not necessary to disassemble and clean the sensor main body 41, and an increase in maintenance time can be suppressed. .

  The dust detection device 1 according to the present embodiment injects air 83 from a position facing the light receiving unit 43 toward the light receiving unit 43. As a result, the dust detection device 1 can remove the dust 92 because the dust 92 can be blown off by the air 83 and discharged out of the sensor body 41 even if the dust 92 stays on the light receiving portion 43 due to adhesion or the like. can do. As a result, a decrease in detection accuracy of the dust sensor 4 due to a decrease in the amount of light received by the light receiving unit 43 can be suppressed.

  More specifically, the dust 92 collected by the collector 3 reflects the light from the light emitting unit 42 when passing through the through-passage 44, and the light receiving unit 43 detects the reflected light. However, if dust 92 stays in the light receiving unit 43 due to adhesion or the like, there is a problem that reflected light cannot be detected with high accuracy. With respect to such a problem, the dust detection device 1 according to the present embodiment can remove the dust 92 by injecting the air 83 to the light receiving unit 43, thereby suppressing a decrease in detection accuracy of the dust sensor 4. be able to.

  The dust detection device 1 according to the present embodiment injects air 83 from the position facing the light emitting unit 42 toward the light emitting unit 42. Thereby, even if the dust 92 stays in the light emitting part 42 due to adhesion or the like, the dust detection device 1 can blow out the dust 92 by the air 83 and discharge it out of the sensor body 41. Therefore, the dust 92 is removed. can do. As a result, a decrease in detection accuracy of the dust sensor 4 due to a decrease in the amount of light from the light emitting unit 42 can be suppressed.

  More specifically, the dust 92 collected by the collector 3 reflects the light from the light emitting unit 42 when passing through the through-passage 44, and the light receiving unit 43 detects the reflected light. 92 is detected. However, if the dust 92 stays in the light emitting unit 42 due to adhesion or the like, there is a problem that the amount of light from the light emitting unit 42 decreases. With respect to such a problem, the dust detection device 1 according to the present embodiment can remove the dust 92 by injecting the air 83 to the light emitting unit 42, and therefore suppresses a decrease in detection accuracy of the dust sensor 4. be able to.

  In the dust detection apparatus 1 according to the present embodiment described above, detection is shorter than time T1 (= L1 / V1) obtained by dividing the length L1 of the through passage 44 by the flow velocity V1 measured by the flow velocity sensor 6. The dust sensor 4 detects dust at the period T2. Thereby, even if it is the state which maintained the flow rate more than a fixed value, since generation | occurrence | production of the dust of a detection failure can be reduced, the dust which has the mass more than a fixed value can be detected accurately. For example, it is possible to individually detect resin or metal dust (dust having a mass equal to or greater than a certain value) generated in a processing step for precision parts or the like.

  In the dust detection device 1 according to the present embodiment, a flow velocity sensor 6 is provided between the dust sensor 4 and the discharge port 29 in the housing 2. Thereby, the flow velocity of the sample air 91 can be measured in a state where the influence of the turbulent flow of the sample air 91 is reduced.

  In the dust detection system 8 according to the present embodiment, the detection cycle T2 is shorter than the time T1 (= L1 / V1) obtained by dividing the length L1 of the through passage 44 by the flow velocity V1 measured by the flow velocity sensor 6. The dust sensor 4 detects dust, and the processing device 81 obtains the amount of dust based on the detection result of the dust sensor 4. Thereby, the quantity of the dust which has a mass more than a fixed value can be detected accurately in a short time. As a result, for example, it is possible to respond in a short time to the generation of dust that causes defects in processing steps of precision parts and the like, and thus it is possible to suppress the generation of defective products.

  In the dust detection device 1 according to the present embodiment described above, the adhesive member 7 is provided at a position facing the opening surface of the through passage 44 between the through passage 44 of the sensor body 41 and the discharge port 29 of the housing 2. ing. Thereby, since the dust immediately after passing through the through-passage 44 can be collected, the dust that has passed through the through-passage 44 can be accurately collected. In addition, since the distance D1 between the adhesive member 7 and the dust sensor 4 is not more than three times the diameter R4 of the through-passage 44, dust can be detected with a high dust speed. It can be reduced that the dust that has come out of 44 falls below the housing 2 and cannot be collected.

  In the dust detection apparatus 1 according to the present embodiment, the plate 71 has a through hole 714 through which the sample air 91 passes. Thereby, the adhesive member 7 can be stably disposed in the housing 2 while suppressing the vibration of the adhesive member 7 due to the flow velocity of the sample air 91 and the turbulent flow of the sample air 91.

  As a modification of the present embodiment, the dust sensor 4 may include a reinforcing mechanism 47 as shown in FIG. The reinforcing mechanism 47 is provided between the joints 54 and 57 and the sensor main body 41. In other words, the reinforcing mechanism 47 is provided in contact with one outer wall of the sensor main body 41 (the front plate 411 in the example of FIG. 11). The joints 54 and 57 are attached to the reinforcing mechanism 47. The reinforcing mechanism 47 includes three reinforcing members 48, 491, and 492.

  The reinforcing member 48 is provided between the joints 54 and 57 and the sensor main body 41 and reinforces the connection portion of the joints 54 and 57. The reinforcing member 48 is formed in a plate shape from metal or resin. The reinforcing member 48 has a recess 481 communicating with the through passage 44. The collector 3 is fitted into the recess 481.

  The reinforcing member 491 is formed in an L shape using metal or resin, and is provided between the joint 54 and the reinforcing member 48. The reinforcing member 491 has a connection port to which the joint 54 is connected. When the reinforcing member 491 is provided between the joint 54 and the reinforcing member 48, the connection port of the reinforcing member 491 communicates with the connection port 451 of the sensor main body 41. In this modification, the joint 54 connects the nozzle 53 and the passage pipe 55 via the reinforcing members 48 and 491 on the side of the collector 3 of the dust sensor 4.

  The reinforcing member 492 is formed in an L shape from metal or resin, and is provided between the joint 57 and the reinforcing member 48. The reinforcing member 492 has a connection port to which the joint 57 is connected. When the reinforcing member 492 is provided between the joint 57 and the reinforcing member 48, the connection port of the reinforcing member 492 communicates with the connection port 452 of the sensor main body 41. In this modification, the joint 57 connects the nozzle 56 and the passage pipe 58 via the reinforcing members 48 and 492 on the side of the collector 3 of the dust sensor 4.

  In the dust detection device 1 according to this modification described above, the joints 54 and 57 are attached to the reinforcing mechanism 47. Thereby, since the mechanical stress to the sensor main body 41 can be reduced, generation | occurrence | production of the crack with respect to the sensor main body 41 and a deformation | transformation can be suppressed.

  Further, in the dust detection device 1 according to this modification, the reinforcing member 48 has a recess 481 that communicates with the through passage 44 of the sensor main body 41 and into which the collector 3 is fitted. Thereby, the dust 92 collected by the collection body 3 can be reliably sent to the through passage 44 of the sensor body 41 while the collection body 3 is securely fixed to the reinforcing member 48.

  The reinforcing mechanism 47 may be provided on the discharge port 29 side (the side opposite to the collector 3 side) of the dust sensor 4. In this case, the joint 54 connects the nozzle 53 and the passage pipe 55 via the reinforcing mechanism 47 on the discharge port 29 side of the dust sensor 4. The joint 57 connects the nozzle 56 and the passage pipe 58 via the reinforcing mechanism 47 on the discharge port 29 side of the dust sensor 4.

  In the present embodiment, the air blow mechanism 5 is not limited to being configured to inject the air 83 to both the light emitting unit 42 and the light receiving unit 43, but only one of the light emitting unit 42 or the light receiving unit 43. Alternatively, the air 83 may be jetted. In other words, the air blow mechanism 5 may be configured to inject the air 83 only to the light receiving unit 43. That is, the air blow mechanism 5 may include only the first air blow mechanism 51. The air blow mechanism 5 may be configured to inject the air 83 only to the light emitting unit 42. That is, the air blow mechanism 5 may include only the second air blow mechanism.

  As a modification of the present embodiment, the processing device 81 may be configured to realize a function as an air control unit. The processing device 81 controls the air supply source 82 as a function of the air control unit. More specifically, when the sample air 91 is not introduced into the housing 2, the processing device 81 causes the air 83 to enter the sensor body 41 of the dust sensor 4 when the amount of the dust 92 is greater than or equal to the threshold value. It may be configured to control the air supply 82 to inject.

  As a modification of the present embodiment, as shown in FIG. 12, the dust detection device 1 includes a supply unit 72 and a winding unit 73 for moving the adhesive member 7 to a position facing the dust sensor 4. May be. The dust detection device 1 of FIG. 12 includes a plate 71 a as a support mechanism for supporting the adhesive member 7 instead of the plate 71. The supply unit 72 and the winding unit 73 are configured to move the adhesive member 7 at a constant speed. The supply unit 72 is configured to supply the adhesive member 7 into the housing 2. The winding unit 73 is configured to wind up the adhesive member 7 from the inside of the housing 2. The winding unit 73 includes a rotating shaft 74 and a motor 75. The adhesive member 7 is wound around the rotation shaft 74. The motor 75 rotates the rotating shaft 74 so as to wind up the adhesive member 7.

  In the dust detection device 1 according to this modification, the dust collecting adhesive member 7 is supplied into the housing 2, the dust 92 contained in the sample air 91 is collected, and then the adhesive member 7 to which the dust 92 is attached. Is wound around the winding unit 73. Thereby, the dust 92 contained in the sample air 91 can be collected in time series without performing the operation of replacing the adhesive member 7. As a result, by examining the dust 92 continuously collected on the adhesive member 7, changes in the dust 92 over time can be easily analyzed. In addition, it is possible to save the trouble of arranging discontinuous adhesive members in time series and attaching them to another mount.

  As a modification of the present embodiment, as shown in FIG. 13, the winding unit 73 of the dust detection device 1 includes a fan 76 and a rotation transmission mechanism 77 instead of the motor 75 (see FIG. 12). It may be. The fan 76 is configured to rotate by the flow of sample air. More specifically, the fan 76 has a flow of sample air that passes through the space (flow path) between the collection body 3 and the dust sensor 4 and the housing 2, that is, a flow of sample air that does not pass through the collection body 3 and the dust sensor 4. It is comprised so that it may rotate. The rotation transmission mechanism 77 is a gear box, for example, and is configured to transmit the rotation of the fan 76 to the rotation shaft 74.

  In the dust detection apparatus 1 according to this modification, the rotating shaft 74 can be rotated by the flow of the sample air 91, so that it is not necessary to use a motor to wind up the adhesive member 7. Thereby, since the power supply and wiring for winding up the adhesive member 7 are unnecessary, the adhesive member 7 can be wound up with less power consumption compared with the case where a motor is used. As a result, the dust 92 that has passed through the sensor body 41 can be collected for a long time. For example, since the adhesive member 7 can be supplied at a constant speed by controlling the flow rate of the sample air 91 to be constant, the dust 92 can be stably collected over a long period of time.

  As a modification of the present embodiment, the processing device 81 of the dust detection system 8 may be configured to output flow velocity information (flow velocity signal) related to the flow velocity measured by the flow velocity sensor 6 to the dust collection mechanism 85. Good. Thereby, the exhaust flow rate of the dust collection mechanism 85 can be controlled, and the flow rate of the sample air 91 can be maintained at a certain value or more.

(Embodiment 2)
As shown in FIGS. 14 and 15, the dust detection device 1 according to the second embodiment includes a plurality of (four in the illustrated example) exhaust fans 12 and 13, and the dust detection device 1 according to the first embodiment ( (See FIG. 1). In addition, about the component similar to the dust detection apparatus 1 which concerns on Embodiment 1, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  The dust detection device 1 of this embodiment includes a plurality of exhaust fans 12 and 13. Each of the plurality of exhaust fans 12 and 13 is attached to the housing 2. In the present embodiment, the exhaust fans 12 and 13 are arranged on four surfaces of the six surfaces of the housing 2 other than the surface having the introduction port 28 and the surface having the interface.

  Each of the plurality of exhaust fans 12 and 13 is configured to exhaust the sample air 91 from the inside of the housing 2 to the outside of the housing 2. In particular, the exhaust fan 12 is provided in the casing 2 on the downstream side of the dust sensor 4, that is, on the discharge port 29.

  The exhaust fan 12 is disposed behind the sensor body 41 of the dust sensor 4. The exhaust fan 12 imparts flow energy to the sample air 91 passing through the through passage 44 of the sensor body 41 by rotating the rotary blade 121 housed in a box-shaped housing, thereby improving the flow velocity. Each exhaust fan 13 imparts flow energy to the sample air 91 by rotating the rotary blade 131 housed in a box-shaped housing, thereby improving the flow velocity.

  In the dust detection device 1 according to the present embodiment described above, the exhaust fans 12 and 13 for discharging the sample air 91 from the inside of the housing 2 to the outside of the housing 2 are provided. Thereby, the dust detection apparatus 1 can be used independently, without connecting the dust detection apparatus 1 to a dust collection mechanism. In addition, the dust 92 can be detected even in a production line in which the dust detection device 1 cannot be connected to the dust collection mechanism. Furthermore, since the dust collection mechanism is unnecessary, the entire device including the dust collection mechanism can be reduced in size. As a result, when the installation location of the dust detection device 1 is changed, it is not necessary to move the dust detection device 1 together with the dust collection mechanism, and therefore the dust detection device 1 can be easily moved.

  As a modification of the present embodiment, as shown in FIG. 16, the housing 2 of the dust detection device 1 may include an intermediate wall 203. The intermediate wall 203 has an intermediate port 204.

  In the present embodiment, the dust detection device 1 includes four exhaust fans 12 and 13, but the number of exhaust fans is not limited to four. The dust detection device 1 may include only one exhaust fan. Alternatively, the dust detection device 1 may include a plurality of exhaust fans other than four.

  In the first and second embodiments, the processing device 81 is provided separately from the dust detection device 1, but is not limited thereto. The processing device 81 may be provided integrally with the dust detection device 1. For example, a microcomputer as the processing device 81 may be provided in the housing 2.

  Moreover, in Embodiment 1, 2, the dust detection apparatus 1 may be provided with the indicator which displays the quantity of dust, for example. The display is installed in the housing 2, for example.

DESCRIPTION OF SYMBOLS 1 Dust detection apparatus 12, 13 Exhaust fan 2 Housing | casing 28 Inlet 29 Outlet 3 Collecting body 4 Dust sensor 41 Sensor main body 42 Light emission part 43 Light receiving part 44 Through-passage 47 Reinforcement mechanism 5 Air blow mechanism 53 Nozzle 54 Joint 8 Dust detection system 81 Processing device 82 Air supply source

Claims (10)

A housing having an inlet for introducing sample air and an outlet for discharging the sample air;
A collector that is housed in the housing and collects dust contained in the sample air introduced from the inlet;
A dust detection device comprising a dust sensor that is housed in the housing and detects the dust collected by the collector,
The dust sensor is
A sensor body having a through-passage through which the dust collected by the collector passes;
A light emitting unit housed in the sensor body and emitting light toward the through-passage;
A light receiving part that is received in the sensor body and receives light reflected from the dust emitted from the light emitting part and passing through the through-passage,
The dust detection device is:
An air blow mechanism that injects air supplied from an air supply source into the sensor body.   The dust detection device according to claim 1, wherein the air blowing mechanism ejects the air toward the light receiving unit from a position facing the light receiving unit in the sensor body.   The dust detection device according to claim 1, wherein the air blow mechanism ejects the air toward the light emitting unit from a position facing the light emitting unit in the sensor body. The air blow mechanism is
A nozzle provided in the sensor body and having an injection port through which the air is injected;
A passage pipe provided outside the sensor body and through which the air from the air supply source passes and a joint for communicating the nozzle;
The dust sensor is
A reinforcing mechanism provided to contact one outer wall of the sensor body;
The dust detection device according to any one of claims 1 to 3, wherein the joint is attached to the reinforcing mechanism.   The dust detection apparatus according to claim 1, further comprising an exhaust fan that discharges the sample air from the inside of the casing to the outside of the casing. In the collector, the opening area of the first opening end facing the introduction port is equal to or larger than the opening area of the introduction port, and is larger than the opening area of the second opening end facing the through path. Formed as
The dust detection device according to claim 1, wherein an opening area of the through passage is smaller than an opening area of the introduction port and an opening area of the discharge port. The dust detection device according to any one of claims 1 to 6,
And a processing device for determining the amount of dust based on the amount of light received by the light receiving unit.   The dust detection system according to claim 7, further comprising the air supply source.   The dust detection system according to claim 8, wherein the processing device controls the air supply source so as to inject the air into the sensor body when the amount of the dust is equal to or greater than a threshold value.   The processing device uses the air supply source to inject the air into the sensor body when the amount of the dust is equal to or greater than the threshold when the sample air is not introduced into the housing. The dust detection system according to claim 9, wherein the dust detection system is controlled.

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