CN113498386A - Particle concentration detection device - Google Patents

Abstract

A particle concentration detection device for detecting the concentration of a particulate matter contained in air outside a vehicle cabin is provided with: a housing member (21) that forms an air passage (24) through which air outside the vehicle compartment flows; a concentration detection unit (51) that detects the concentration of particulate matter contained in the air outside the vehicle compartment that flows through the air passage; and a sensor case (52) that houses the concentration detection section. The sensor housing has: a sensor inlet (521) for introducing air outside the vehicle compartment into the sensor housing from the air passage; and a sensor outflow port (522) through which air in the sensor case flows out from the sensor case to the air passage. The sensor inlet port and the sensor outlet port are respectively open to the air passage of the case member.

Description

Particle concentration detection device

Cross reference to related applications

The present application is based on japanese patent application No. 2019-34424, which was filed on 27/2/2019, and the contents of the disclosure are incorporated herein by reference.

Technical Field

The present invention relates to a particle concentration detection device for detecting the concentration of a particulate substance contained in air.

Background

Conventionally, there is a device described in patent document 1. The device is provided with: a housing having an outside circulating air outlet and an inside circulating air outlet; and an air quality sensor for detecting air quality, wherein the air quality sensor is arranged at an external air circulation air outlet of the shell.

Documents of the prior art

Patent document

Patent document 1: chinese utility model bulletin No. 207328048 specification

Disclosure of Invention

The device shown in patent document 1 does not explicitly describe a specific air quality detection method, and according to the study by the inventors of the present application, when the pressure of air pushed into the outside of the vehicle compartment varies due to the vehicle traveling wind, the detection accuracy of the sensor may vary. The purpose of the present invention is to suppress variations in detection accuracy of a sensor due to variations in the pressure of air introduced from outside the vehicle.

According to one aspect of the present invention, a particle concentration detection device for detecting a concentration of a particulate matter contained in air outside a vehicle compartment includes: a housing member forming an air passage for air flow outside the vehicle compartment; a concentration detection unit that detects a concentration of particulate matter contained in air outside the vehicle compartment flowing through the air passage; and a sensor case that houses the concentration detection section, the sensor case having: a sensor inlet port for introducing air outside the vehicle compartment into the sensor housing from the air passage; and a sensor outlet port that causes air inside the sensor case to flow out from the inside of the sensor case to the air passage, the sensor inlet port and the sensor outlet port being open to the air passage of the case member, respectively.

According to the above configuration, since the sensor inlet and the sensor outlet are respectively opened to the air passage of the case member, the pressure of the air outside the vehicle compartment applied to the sensor inlet and the pressure of the air outside the vehicle compartment applied to the sensor outlet are cancelled out with each other, and thus variation in detection accuracy due to variation in the pressing pressure of the air outside the vehicle compartment can be suppressed.

Note that the parenthesized reference numerals for each component and the like indicate an example of the correspondence relationship between the component and the like and the specific component and the like described in the embodiment described later.

Drawings

Fig. 1 is an external view of a blower unit of a vehicle air conditioner including a particle concentration detection device according to a first embodiment.

Fig. 2 is a diagram schematically showing a schematic configuration of a vehicle air conditioner including the particle concentration detection device according to the first embodiment.

Fig. 3 is an external view of an inside/outside air switching door of a vehicle air conditioner including the particle concentration detection device according to the first embodiment.

Fig. 4 is a schematic cross-sectional view of the particle concentration detection apparatus of the first embodiment.

Fig. 5 is a view in the direction V in fig. 4, and is a view showing a state in which the sensor housing is tilted to the front side.

Fig. 6 is a diagram showing a comparative example of the particle concentration detection device.

Fig. 7 is a schematic sectional view of a particle concentration detection device according to a second embodiment.

Fig. 8 is a schematic cross-sectional view of a particle concentration detection apparatus according to a third embodiment.

Fig. 9 is a schematic cross-sectional view of a particle concentration detection apparatus of a fourth embodiment.

Fig. 10 is a schematic cross-sectional view of a particle concentration detection apparatus according to a fifth embodiment.

Fig. 11 is a schematic cross-sectional view of a particle concentration detection apparatus according to a sixth embodiment.

Fig. 12 is a schematic cross-sectional view of a particle concentration detection apparatus according to a seventh embodiment.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, the same or corresponding portions are denoted by the same reference numerals in the drawings.

(first embodiment)

A particle concentration detection device according to a first embodiment will be described with reference to fig. 1 to 6. As shown in fig. 1, the particulate concentration detection device has a PM sensor 50 and is disposed in a blower unit of a vehicle air conditioner 1 that performs air conditioning of a vehicle. The particle concentration detection device of the present embodiment detects the concentration of the particulate matter, i.e., the dust concentration, contained in the air outside the vehicle interior, which is introduced into the air conditioning casing 21 of the air conditioning device 1 for a vehicle by the operation of the blower 23. The air conditioning casing 21 corresponds to a casing member.

As shown in fig. 2, the air conditioner 1 for a vehicle includes an air conditioning unit 2 and an air conditioning control device 40. The air conditioning unit 2 is a vehicle air conditioning unit that is installed in a vehicle interior and performs air conditioning in the vehicle interior. For example, the air conditioning unit 2 is provided in an instrument panel disposed on the vehicle front side in the vehicle compartment.

The air conditioning unit 2 includes: an air conditioning case 21, an inside/outside air switching door 22, a blower 23, an evaporator 26, a heater core 27, an air mix door 28, an air filter 30, a blowout opening door 254, 255, 256, and the like.

The air conditioning case 21 is formed of a resin having a certain degree of elasticity and also excellent strength. As the resin forming the air conditioning casing 21, for example, polypropylene can be cited. The air conditioning casing 21 constitutes a casing of the air conditioning unit 2, and an air passage 24 through which air blown into the vehicle interior flows is formed inside the air conditioning casing 21. Further, the air conditioning casing 21 includes, on the upstream side in the airflow direction of the air passage 24: an interior air inlet 241 for introducing interior air from a predetermined position in the vehicle interior into the air passage 24; and an outside air inlet 242 for introducing outside air from the outside of the vehicle into the air passage 24. Here, the inside air refers to air inside the vehicle compartment, and the outside air refers to air outside the vehicle compartment.

The air conditioning casing 21 has a plurality of outlet openings 251, 252, and 253 on the downstream side in the airflow direction of the air passage 24 for blowing air from the air passage 24 to the front seat area in the vehicle interior. The plurality of outlet openings 251, 252, and 253 include a face outlet opening 251, a foot outlet opening 252, and a defroster outlet opening 253.

The face outlet opening 251 blows out the air-conditioning wind toward the upper body of the occupant seated in the front seat. The foot outlet opening 252 blows out the air conditioning wind toward the occupant's foot. The defroster outlet opening 253 blows out the conditioned air toward the front window of the vehicle.

Inside the air conditioning casing 21, there are provided: an inside/outside air switching door 22, a blower 23, an evaporator 26, a heater core 27, an air mixing door 28, and the like.

The inside/outside air switching door 22 continuously adjusts the opening area of the inside air inlet 241 and the opening area of the outside air inlet 242. As shown in fig. 3, the inside/outside air switching door 22 is a revolving door including a door portion 221 that opens and closes an inside air introduction port 241 or an outside air introduction port 242, a rotation shaft 222, and a support portion 223 that connects the door portion 221 and the rotation shaft 222. The inside/outside air switching door 22 corresponds to a door member.

The inside/outside air switching door 22 is driven by an actuator such as a servo motor, not shown. The inside/outside air switching door 22 is rotated so as to close one of the inside air inlet 241 and the outside air inlet 242 as the other is opened. Thus, the inside/outside air switching door 22 can adjust the ratio of the amount of inside air to the amount of outside air introduced into the air passage 24.

The intake modes for taking in air into the air passage 24 include an inside air mode for introducing inside air into the interior of the vehicle and an outside air mode for introducing outside air into the exterior of the vehicle. For example, in the inside air mode in which the inside air is introduced only into the air passage 24, the inside/outside air switching door 22 is positioned at an operation position at which the inside air introduction port 241 is opened and the outside air introduction port 242 is closed. Conversely, in the outside air mode in which only outside air is introduced into the air passage 24, the inside/outside air switching door 22 is positioned at an operating position at which the inside air introduction port 241 is closed and the outside air introduction port 242 is opened.

The blower 23 is a centrifugal blower for blowing air, and includes: a centrifugal fan 231 disposed in the air passage 24; and a motor, not shown, for rotationally driving the centrifugal fan 231. When the centrifugal fan 231 of the blower 23 is rotationally driven, an air flow is formed in the air passage 24. Accordingly, the air introduced into the air passage 24 from the inside air inlet 241 or the outside air inlet 242 flows through the air passage 24, and is blown out from at least one of the face blowout opening 251, the foot blowout opening 252, and the defroster blowout opening 253. Further, the air flows in the direction indicated by the arrow Ar substantially on the downstream side in the air flow direction of the centrifugal fan 231 in the air passage 24.

The face blowout opening door 254 is provided in the face blowout opening 251, and adjusts the opening area of the face blowout opening 251. The foot outlet opening section 255 is provided in the foot outlet opening 252, and the opening area of the foot outlet opening 252 is adjusted. The defroster outlet opening door 256 is provided in the defroster outlet opening 253, and adjusts the opening area of the defroster outlet opening 253.

The evaporator 26 is a heat exchanger for cooling the air flowing through the air passage 24. The evaporator 26 exchanges heat between the air passing through the evaporator 26 and the refrigerant, thereby cooling the air and evaporating the refrigerant.

The heater core 27 is a heat exchanger for heating the air flowing through the air passage 24. The heater core 27 exchanges heat between, for example, engine cooling water and air passing through the heater core 27, and heats the air with the heat of the engine cooling water. The heater core 27 is disposed downstream of the evaporator 26 in the airflow direction.

An air mix door 28 is provided between the evaporator 26 and the heater core 27 of the air conditioning unit 2. The air mix door 28 adjusts the ratio of the air volume that passes through the evaporator 26 and bypasses the heater core 27 to the air volume that passes through the heater core 27 after passing through the evaporator 26.

The air filter 30 is disposed on the upstream side of the blower 23 with respect to the air flow flowing through the air passage 24. The air filter 30 captures dust and the like contained in the air passing through the air filter 30 to some extent. Therefore, the air from which dust and the like are removed by the air filter 30 is sucked into the blower 30. That is, the air from which dust and the like are removed by the air filter 30 is blown from the blower 30.

A PM sensor 50 is provided on the outer peripheral surface of the air conditioning case 21 on the upstream side of the air filter 30 with respect to the air flow of the air flowing through the air passage 24. The PM sensor 50 is disposed in the vicinity of the outside air inlet 242.

Next, the air-conditioning control device 40 will be explained. The air-conditioning control device 40 shown in fig. 2 is a control device that controls the air-conditioning unit 2. Specifically, the air conditioning control device 40 is an electronic control device including a storage unit configured by a non-transitory tangible storage medium such as a semiconductor memory and a processor. The air conditioning control device 40 executes the computer program stored in the storage unit. By executing the computer program, a method corresponding to the computer program is executed. That is, the air conditioning control device 40 executes various control processes in accordance with the computer program.

The air conditioning control device 40 outputs a control signal to each actuator included in the air conditioning unit 2 to control the operation of each actuator. In brief, the air conditioning control device 40 performs various air conditioning controls in the air conditioning unit 2. For example, the air blower 23, the inside/outside air switching door 22, the air mix door 28, the face outlet opening door 254, the foot outlet opening door 255, and the defroster outlet opening door 256 are drive-controlled by the air conditioning control device 40.

As shown in fig. 2, the air conditioning control device 40 is electrically connected to an operation device 44 and a display device 46, in addition to sensors such as a PM sensor 50 and actuators such as a door. Air conditioning control device 40 also performs the following processing: the display device 46 displays the concentration of particulate matter contained in the air detected by the PM sensor 50 in response to the operation of the operation device 44 by the occupant.

The inside/outside air switching door 22 is disposed in the air conditioning casing 21 on the upstream side of the air filter 30 with respect to the air flow of the air flowing through the air passage 24. A casing outlet 211 and a casing inlet 212 connected to the PM sensor 50 are formed on a surface of the air conditioning casing 21 facing the support portion 223 of the inside/outside air switching door 22.

When the door portion 221 of the inside/outside air switching door 22 is in a state where the inside air inlet port 241 is opened and the outside air inlet port 242 is closed, the support portion 223 of the inside/outside air switching door 22 shown in fig. 3 is disposed at a position facing the case outlet port 211 and the case inlet port 212.

When the door portion 221 of the inside/outside air switching door 22 is in a state of closing the inside air inlet 241 and opening the outside air inlet 242, the support portion 223 of the inside/outside air switching door 22 is disposed so as to avoid positions facing the casing outlet 211 and the casing inlet 212.

Next, the particle concentration detection device of the present embodiment will be described with reference to fig. 4. The particle concentration detection device includes an air conditioning case 21 forming an air passage 24 through which air flows, and a PM sensor 50.

The PM sensor 50 of the present embodiment detects the concentration of particulate matter contained in the air introduced into the air conditioning case 21 through the outside air inlet 242. The PM sensor 50 is disposed on the upstream side of the air filter 30 in the air passage 24 through which air blown out into the vehicle room flows. Therefore, the PM sensor 50 detects the concentration of dust contained in the air before passing through the air filter 30. That is, the PM sensor 50 detects the concentration of dust contained in air containing dust and raindrops outside the vehicle compartment.

The PM sensor 50 is an optical dust sensor configured to detect the dust concentration by a light scattering method. The PM sensor 50 includes: a concentration detection unit 51 that detects the concentration of particulate matter contained in the air outside the vehicle compartment flowing through the air passage 24, a sensor case 52 that houses the concentration detection unit 51, and an air blowing fan 53.

The concentration detection unit 51 includes: the dust concentration in the air is detected by receiving scattered light scattered by the granular material upon contact with the light irradiated from the light-emitting section by the light-receiving section.

The sensor case 52 is a case that houses the concentration detection unit 51, and is formed of resin or the like. A part of the air flowing through the air passage 24 formed in the air conditioning case 21 flows inside the sensor case 52 of the PM sensor 50.

The sensor housing 52 has: a sensor inlet 521, the sensor inlet 521 introducing air outside the vehicle interior into the sensor case 52 through the air passage 24; and a sensor outlet 522 through which the air in the sensor case 52 flows out from the inside of the sensor case 52 to the air passage 24.

Fig. 5 is a view in the direction V in fig. 4, showing a state in which the sensor housing 52 is tilted to the front side. As shown in fig. 5, the sensor inlet 521 and the sensor outlet 522 are disposed at positions shifted in the vertical direction and in the horizontal direction.

The blower fan 53 generates an air flow inside the sensor housing 52. The blower fan 53 introduces air outside the vehicle compartment flowing through the air passage 24 into the sensor case 52 through the sensor inlet 521, and discharges the air inside the sensor case 52 into the air passage 24 through the sensor outlet 522.

The air conditioning casing 21 has: a case outlet 211, the case outlet 211 guiding the air outside the vehicle compartment flowing through the air passage 24 to the sensor inlet 521; and a casing inlet 212, the casing inlet 212 guiding the air flowing out from the sensor outlet 522 to the air passage 24.

The casing outlet 211 and the casing inlet 212 are open to the air passage of the air conditioning casing 21. The casing outlet 211 is disposed on the downstream side of the casing inlet 212 in the main flow direction of the air outside the vehicle compartment flowing through the air passage 24.

The air conditioning casing 21 further includes a sensor flow path 213, and the sensor flow path 213 connects a space including the casing outlet 211 and a space including the casing inlet 212, and connects a space including the sensor inlet 521 and a space including the sensor outlet 522.

The sensor flow path 213 is provided with a partition plate 214, and the partition plate 214 partitions the internal space of the sensor flow path 213 into a space from the casing outlet 211 to the sensor inlet 521 and a space from the sensor outlet 522 to the casing inlet 212.

The sensor case 52 has a first protrusion 531, and the first protrusion 531 protrudes toward the sensor flow path 213 side and guides air outside the vehicle interior from the sensor outlet 522 to the inside of the sensor case 52. Further, a second protrusion 532 is provided, and this second protrusion 532 protrudes toward the sensor flow path 213 side and guides air inside the sensor case 52 to the sensor outflow port 522. The sensor outlet 522 is formed on the lower surface of the first protrusion 531 in the vertical direction, and the sensor inlet 521 is formed on the lower surface of the second protrusion 532 in the vertical direction.

Here, as shown in fig. 6, a configuration in which a rectangular parallelepiped sensor case 52 is disposed on the outer peripheral surface of the air conditioning case 21 forming the air passage 24 is considered. A sensor inlet 521 is disposed in the sensor case 52 at a position on the air passage 24 side, and a sensor outlet 522 is disposed on a surface of the sensor case 52 facing the sensor inlet 521.

In such a configuration, a large difference is generated between the pressure of the air applied to the sensor inlet 521 and the pressure of the air applied to the sensor outlet 522. Therefore, the influence of the variation in the pressing pressure of the air outside the vehicle compartment on the detection accuracy becomes large.

In contrast, in the particle concentration detection device of the present embodiment, the air conditioning casing 21 includes: a case outlet 211, the case outlet 211 guiding the air outside the vehicle compartment flowing through the air passage 24 to the sensor inlet 521; and a housing inlet 212, the housing inlet 212 directing air from the sensor outlet 522 to the air passage 24. The casing outlet 211 and the casing inlet 212 are open to the air passage 24 of the air conditioning casing 21.

Therefore, the pressure of the air outside the vehicle interior applied to the sensor inlet 521 and the pressure of the air outside the vehicle interior applied to the sensor outlet 522 cancel each other out, and variation in detection accuracy due to variation in the pressure of the air outside the vehicle interior is suppressed.

As described above, the particle concentration detection device of the present embodiment is a particle concentration detection device that detects the concentration of particulate matter contained in the air outside the vehicle compartment, and includes the air conditioning casing 21, and the air conditioning casing 21 forms the air passage 24 through which the air outside the vehicle compartment flows.

Further, the apparatus comprises: a concentration detection unit 51 for detecting the concentration of particulate matter contained in the air outside the vehicle compartment flowing through the air passage 24 by the concentration detection unit 51; and a sensor case 52, the sensor case 52 housing the density detection portion 51. Further, the sensor housing 52 has: a sensor inlet 521, the sensor inlet 521 introducing air outside the vehicle compartment into the sensor case 52 from the air passage; and a sensor outflow opening 522 that allows air inside the sensor case 52 to flow out of the sensor case 52.

The casing outlet 211 and the casing inlet 212 are open to the air passage 24 of the air conditioning casing 21.

According to the above configuration, the sensor inlet 521 and the sensor outlet 522 are open to the air passage 24 of the air-conditioning casing 21. Therefore, the pressure of the air outside the vehicle interior, which is applied to the sensor inlet 521, and the pressure of the air outside the vehicle interior, which is applied to the sensor outlet 522, cancel each other out, and variation in detection accuracy due to variation in the pressure of the air outside the vehicle interior can be suppressed.

Further, the sensor case 52 is fixed to the outer peripheral surface of the air conditioning case 21. Therefore, the sensor case 52 and the air conditioning case 21 can be integrated and mounted on the vehicle.

Further, the air conditioning casing 21 includes: a case outlet 211, the case outlet 211 guiding the air outside the vehicle compartment flowing through the air passage 24 to the sensor inlet 521; and a housing inlet 212, the housing inlet 212 directing air from the sensor outlet 522 to the air passage 24.

The case outlet 211 is disposed on the downstream side of the case inlet 212 with respect to the air flow of the air outside the vehicle compartment flowing through the air passage 24. In this way, the case inlet 212 can be disposed on the downstream side of the air flow of the air outside the vehicle compartment flowing through the air passage 24 with respect to the case outlet 211.

The air conditioning casing 21 further includes a sensor flow path 213, and the sensor flow path 213 connects a space including the casing outlet 211 and a space including the casing inlet 212, and connects a space including the sensor inlet 521 and a space including the sensor outlet 522. Therefore, the influence of fluctuations in the air flow outside the vehicle compartment flowing through the air conditioning casing 21 can be further reduced.

In the sensor flow path 213, a partition plate 214 is formed, and the partition plate 214 partitions the internal space of the sensor flow path 213 into a space from the casing outlet 211 to the sensor inlet 521 and a space from the sensor outlet 522 to the casing inlet 212. Therefore, air can be prevented from circulating between the casing outlet 211 and the casing inlet 212.

The lower end of the case outlet 211 is continuously connected to the bottom surface of the sensor flow path 213. Therefore, water can be prevented from accumulating between the lower end of the case outlet 211 and the bottom surface of the sensor flow path 213, and drainage can be improved.

The sensor case 52 has a first protrusion 531, and the first protrusion 531 protrudes toward the sensor flow path 213 side and guides the air outside the vehicle interior from the sensor inlet 521 to the inside of the sensor case 52. The sensor housing further includes a second protrusion 532, and the second protrusion 532 protrudes toward the sensor flow path 213 and guides air from the inside of the sensor housing 52 to the sensor outflow port 522. The sensor inlet 521 is formed on the surface of the first protrusion 531 on the lower side in the vertical direction, and the sensor outlet 522 is formed on the surface of the second protrusion 532 on the lower side in the vertical direction.

Therefore, foreign matter can be prevented from entering the sensor case 52 from the sensor inlet 521 and the sensor outlet 522.

The sensor inlet 521 is disposed vertically above the case outlet 211, and the sensor outlet 522 is disposed vertically above the case inlet 212. Therefore, water or the like can be prevented from entering the sensor housing 52.

The particle concentration detection device of the present embodiment includes the blower fan 53, and the blower fan 53 introduces air outside the vehicle interior from the sensor inlet 521 into the sensor case 52 and blows air inside the sensor case 52 from the sensor outlet 522.

Therefore, a predetermined amount of air outside the vehicle compartment can be introduced into the sensor case while suppressing the influence of the variation in the pressing pressure of the air outside the vehicle compartment.

(second embodiment)

The structure of the particle concentration detection apparatus according to the second embodiment will be described with reference to fig. 7. The particle concentration detection device of the present embodiment includes a sensor flow channel 213. The bottom surface of the sensor flow path 213 is inclined upward and downward as it approaches the air conditioning casing 21.

Therefore, water that has flowed into the sensor housing from the sensor flow channel can be discharged to the housing member side.

(third embodiment)

The configuration of the particle concentration detection apparatus according to the third embodiment will be described with reference to fig. 8. The particle concentration detection device of the present embodiment is provided with a partition plate 214 in the sensor flow path 213, and the partition plate 214 partitions the internal space of the sensor flow path 213 into a space from the casing outlet 211 to the sensor inlet 521 and a space from the sensor outlet 522 to the casing inlet 212.

A communicating portion 214a is formed in the partition plate 214, and the communicating portion 214a communicates between a space from the casing outlet port 211 to the sensor inlet port 521 and a space from the sensor outlet port 522 to the casing inlet port 212. The communicating portion 214a of the present embodiment is constituted by a communicating hole.

The communicating portion 214a is formed in a portion of the partition plate 214 closer to the sensor case 52 than the center of the air conditioning case 21 and the sensor case 52.

Therefore, when the sensor case 52 is displaced downward in the vertical direction with respect to the air-conditioning case 21, water in the sensor flow path 213 can be discharged through the communication portion 214 a.

In the present embodiment, a communication portion 214a is formed in a portion of partition plate 214 closer to sensor case 52 than the center of air-conditioning case 21 and sensor case 52. In contrast, the communicating portion 214a may be formed in a portion of the partition plate 214 closer to the air conditioning case 21 than the center of the air conditioning case 21 and the sensor case 52.

This allows the water that has flowed into the sensor case 52 from the sensor flow path 213 to be discharged to the air conditioning case 21 side. Even when different pressing pressures are applied to the case outlet 211 and the case inlet 212 due to drift, the air flows from the higher pressure side to the lower pressure side through the communicating portion 214a, and the pressures are averaged, so that the influence on the detection accuracy can be reduced.

The communicating portion 214a of the present embodiment is formed of a communicating hole, but the communicating portion 214a may be formed by a gap.

(fourth embodiment)

The configuration of the particle concentration detection apparatus according to the fourth embodiment will be described with reference to fig. 9. In the particle concentration detection device of the present embodiment, louver-shaped louvers 215 are disposed at the casing inlet 212 and the casing outlet 211. Therefore, intrusion of foreign matter into the sensor housing 52 can be prevented.

In the present embodiment, louver-shaped louvers 215 are disposed in the casing outlet 211 and the casing inlet 212. On the other hand, louver-shaped louvers 215 may be disposed in at least one of the casing outlet 211, the casing inlet 212, the sensor inlet 521, and the sensor outlet 522.

(fifth embodiment)

The structure of the particle concentration detection apparatus according to the fifth embodiment will be described with reference to fig. 10. The inside of the sensor flow path 213 of the particle concentration detection device of the present embodiment has a labyrinth structure in which the internal space of the sensor flow path 213 is formed in a labyrinth shape. Specifically, projections 521a and 522a for forming the inner space of the sensor flow path 213 into a labyrinth shape are provided inside the sensor flow path 213 b.

As described above, the inside of the sensor flow path 213 of the particle concentration detection device has a labyrinth structure in which the internal space of the sensor flow path 213 is formed in a labyrinth shape. Therefore, it is possible to prevent a large foreign object that is not a detection target from entering the sensor housing 52.

Further, the air conditioning casing 21 is provided with a rib 216, and the rib 216 blocks the air flow of the air outside the vehicle compartment flowing through the air passage 24, and the casing outlet 211 and the casing inlet 212 are disposed on the upstream side of the rib 216 with respect to the air flow of the air outside the vehicle compartment flowing through the air passage 24.

Therefore, the air outside the vehicle compartment that hits the rib 216 can be prevented from being pushed into the case outlet 211 and the case inlet 212.

In the present embodiment, the case outlet 211 and the case inlet 212 are disposed on the upstream side of the rib 216 with respect to the air flow of the air outside the vehicle compartment flowing through the air passage 24. In contrast, the case outlet 211 and the case inlet 212 may be disposed on the downstream side of the rib 216 with respect to the air flow of the air outside the vehicle compartment flowing through the air passage 24. That is, a step is provided between the casing outlet 211 and the rib 216 and between the casing inlet 212 and the rib 216. By providing a step between the case outlet 211 and the rib 216 and between the case inlet 212 and the rib 216, the air outside the vehicle compartment that hits the rib 216 can be prevented from being pushed into the case outlet 211 and the case inlet 212.

The rib 216 may be, for example, a sealing member that seals a gap between the door member 22 and the outside air inlet 242, and the door member 22 opens and closes the outside air inlet 242 that introduces the air outside the vehicle compartment into the air passage 24. The rib 216 prevents air from leaking from the gap between the door member 22 and the outside air inlet 242.

(sixth embodiment)

The configuration of the particle concentration detection apparatus according to the sixth embodiment will be described with reference to fig. 11. In the particle concentration detection device of the present embodiment, the filter 61 is disposed at the casing outlet 211, and the filter 62 is disposed at the casing inlet 212. A filter 63 is disposed at the sensor inlet 521, and a filter 64 is disposed at the sensor outlet 522. Therefore, the intrusion of foreign matter into the sensor housing can be prevented.

In the present embodiment, the filters 61 and 62 are disposed at the casing outlet 211 and the casing inlet 212, but a filter may be disposed at least at one of the casing outlet 211 and the casing inlet 212.

In the present embodiment, the filters 63 and 64 are disposed at the sensor inlet 521 and the sensor outlet 522, but a filter may be disposed at least at one of the sensor inlet 521 and the sensor outlet 522.

(seventh embodiment)

The configuration of the particle concentration detection apparatus according to the seventh embodiment will be described with reference to fig. 12. The casing inlet 212 of the particle concentration detection device of the present embodiment is disposed on the downstream side of the casing outlet 211 with respect to the air outside the vehicle compartment flowing through the air passage 24. By providing such a configuration, the air that flows into the sensor housing 52 from the housing outlet 211 and returns to the air passage 24 from the housing inlet 212 can be prevented from flowing into the sensor housing 52 again from the housing outlet 211.

(other embodiments)

(1) In the above embodiments, the example in which the PM sensor 50 is provided in the air conditioning unit that introduces at least one of the inside air and the outside air into the air conditioning case is shown. In contrast, the PM sensor 50 may be provided in an air conditioning unit having a double-layer structure of inside and outside air in which the window of the windshield disposed above the vehicle is cleaned using outside air and the passenger's feet are heated using inside air.

(2) In each of the above embodiments, the sensor flow path 213 is provided in the air conditioning casing 21, and the air conditioning casing 21 and the sensor casing 52 are coupled via the sensor flow path 213, but the air conditioning casing 21 and the sensor casing 52 may be directly coupled without providing the sensor flow path 213.

The present invention is not limited to the above-described embodiments, and can be modified as appropriate. The above embodiments are not independent of each other, and can be combined as appropriate except when the combination is obviously impossible. In the above embodiments, it is obvious that the elements constituting the embodiments are not essential except for the case where they are specifically and clearly indicated to be essential and the case where they are clearly considered to be essential in principle. In the above embodiments, when numerical values such as the number, numerical value, amount, and range of the constituent elements of the embodiments are mentioned, the number is not limited to a specific number unless otherwise explicitly stated or clearly limited to a specific number in principle. In the above embodiments, when referring to the material, shape, positional relationship, and the like of the constituent elements and the like, the material, shape, positional relationship, and the like are not limited to those unless specifically indicated or limited to a specific material, shape, positional relationship, and the like in principle.

(conclusion)

According to a first aspect shown in part or all of the above embodiments, a particle concentration detection device that detects a concentration of a particulate matter contained in air outside a vehicle compartment includes a housing member that forms an air passage through which the air outside the vehicle compartment flows. Further, the apparatus comprises: a concentration detection unit that detects a concentration of particulate matter contained in air outside the vehicle compartment flowing through the air passage; and a sensor case that houses the concentration detection section. In addition, the sensor housing has: a sensor inlet port for introducing air outside the vehicle compartment into the sensor housing from the air passage; and a sensor outlet port that causes air inside the sensor case to flow out from the inside of the sensor case to the air passage. The sensor inlet and the sensor outlet are open to the air passage of the case member.

In addition, according to a second aspect, the sensor housing is fixed to the outer peripheral surface of the case member. Therefore, the sensor housing and the housing member can be integrated and mounted on the vehicle.

In addition, according to a third aspect, the housing member includes: a case outlet port that guides air outside the vehicle compartment flowing through the air passage to the sensor inlet port; and a case inlet port that guides air outside the vehicle compartment from the sensor outlet port to the air passage.

The case inlet is disposed on the downstream side of the case outlet with respect to the air flow of the air outside the vehicle compartment flowing through the air passage. In this way, the case inlet port can be disposed on the upstream side of the air flow of the air outside the vehicle compartment flowing through the air passage with respect to the case outlet port.

In addition, according to a fourth aspect, the case member includes a sensor flow path that connects the space including the case outlet and the space including the case inlet and connects the space including the sensor inlet and the space including the sensor outlet. Therefore, the influence of the fluctuation of the air flow outside the vehicle compartment flowing through the case member can be further reduced.

In addition, according to a fifth aspect, in the sensor flow path, the bottom surface of the sensor flow path is inclined downward in the vertical direction as the bottom surface is closer to the case member.

Therefore, water that has flowed into the sensor housing from the sensor flow channel can be discharged to the housing member side.

In addition, according to a sixth aspect, the lower end of the casing inlet is continuously connected to the bottom surface of the sensor flow path. Therefore, water can be prevented from accumulating between the lower end of the casing inlet and the bottom surface of the sensor flow path, and drainage can be improved.

In addition, according to a seventh aspect, a partition plate is formed in the sensor flow path, and the partition plate partitions an internal space of the sensor flow path into a space from the case outlet port to the sensor inlet port and a space from the sensor outlet port to the case inlet port. Therefore, air can be prevented from circulating between the casing outlet and the casing inlet.

In addition, according to an eighth aspect, the partition plate is provided with a communicating portion that communicates between a space from the casing outlet to the sensor inlet and a space from the sensor outlet to the casing inlet.

Therefore, water that has flowed into the sensor housing from the sensor flow channel can be discharged to the housing member side. Even when different pressing pressures are applied to the case outlet and the case inlet due to drift, the air flows from the side of higher pressure to the side of lower pressure through the communicating portion, and the pressure is averaged, thereby reducing the influence on the detection accuracy.

In addition, according to a ninth aspect, the communication portion is formed in a portion of the partition plate closer to the sensor housing than the centers of the air conditioning housing and the sensor housing.

Therefore, when the sensor case is displaced downward in the vertical direction with respect to the air-conditioning case, water in the sensor flow path can be discharged through the communication portion.

In addition, according to a tenth aspect, the sensor case has a first projecting portion that projects toward the sensor flow path side and guides air in the vehicle interior from the sensor inlet port to the inside of the sensor case. The sensor housing has a first protrusion that protrudes toward the sensor flow path side and guides air from the vehicle interior to the sensor flow outlet. The sensor inlet is formed on a lower surface of the first protruding portion in the vertical direction, and the sensor outlet is formed on a lower surface of the second protruding portion in the vertical direction.

Therefore, foreign matter can be prevented from entering the sensor case from the sensor inlet and the sensor outlet.

In addition, according to an eleventh aspect, the air conditioning case is provided with a rib that blocks the air flow of the air outside the vehicle compartment flowing through the air passage. The casing outlet and the casing inlet are disposed on the upstream side or the downstream side of the air flow of the air outside the vehicle compartment flowing through the air passage, as compared with the ribs.

Therefore, the air outside the vehicle compartment that hits the rib can be prevented from being pushed into the casing outlet and the casing inlet.

In addition, according to a twelfth aspect, a louver-shaped louver is disposed on at least one of the casing outlet and the casing inlet. Therefore, intrusion of foreign matter into the sensor housing can be prevented.

In addition, according to a thirteenth aspect, the inside of the sensor flow path has a labyrinth structure in which the internal space of the sensor flow path is formed in a labyrinth shape.

Therefore, it is possible to prevent a large foreign object that is not a detection target from entering the sensor housing.

In addition, according to the fourteenth aspect, the sensor inlet is disposed above the case outlet in the vertical direction, and the sensor outlet is disposed above the case inlet in the vertical direction. Therefore, water or the like can be prevented from entering the sensor housing.

In addition, according to a fifteenth aspect, a filter is disposed at least one of the casing outlet and the casing inlet. Therefore, the intrusion of foreign matter into the sensor housing can be prevented.

In addition, according to a sixteenth aspect, a filter is disposed at least one of the sensor inlet and the sensor outlet. Therefore, the intrusion of foreign matter into the sensor housing can be prevented.

Further, according to a seventeenth aspect, the air blower fan is provided that introduces air outside the vehicle interior from the sensor inlet port into the sensor case and blows air outside the vehicle interior from the sensor outlet port to the air passage.

Therefore, while suppressing the influence of the variation in the pressing pressure of the air outside the vehicle compartment, a predetermined amount of air outside the vehicle compartment can be introduced into the sensor case.

Claims (19)

1. A particle concentration detection device for detecting the concentration of a particulate matter contained in air outside a vehicle, comprising:

a housing member (21) that forms an air passage (24) through which air outside the vehicle compartment flows;

a concentration detection unit (51) that detects the concentration of the particulate matter contained in the air outside the vehicle compartment that flows through the air passage; and

a sensor case (52) that houses the concentration detection section,

the sensor housing has: a sensor inlet (521) for introducing air outside the vehicle compartment into the sensor housing from the air passage; and a sensor outflow port (522) that causes air inside the sensor case to flow out from the inside of the sensor case to the air passage,

the sensor inlet port and the sensor outlet port are respectively open to the air passage of the case member.

2. The particle concentration detection apparatus according to claim 1,

the sensor housing is fixed to an outer peripheral surface of the housing member.

3. The particle concentration detection apparatus according to claim 1 or 2,

the sensor flow path (213) is provided, and connects a space including the sensor inlet and a space including the sensor outlet.

4. The particle concentration detection apparatus according to claim 3,

the housing member has: a case outlet (211) that guides the air outside the vehicle compartment flowing through the air passage to the sensor inlet; and a case inflow port (212) that guides the air outside the vehicle compartment from the sensor outflow port to the air passage.

5. The particle concentration detection apparatus according to claim 4,

the case inlet is disposed on the downstream side of the air flow of the air outside the vehicle compartment flowing through the air passage with respect to the case outlet.

6. The particle concentration detection apparatus according to claim 3,

in the sensor flow path, a bottom surface of the sensor flow path is inclined downward in a vertical direction as it approaches the case member.

7. The particle concentration detection apparatus according to claim 4,

the lower end of the casing inlet is continuously connected to the bottom surface of the sensor flow path.

8. The particle concentration detection apparatus according to claim 4,

a partition plate (214) is formed in the sensor flow path, and divides an internal space of the sensor flow path into a space from the case outlet to the sensor inlet and a space from the sensor outlet to the case inlet.

9. The particle concentration detection apparatus according to claim 8,

a communication portion (214a) that communicates between a space from the case outlet to the sensor inlet and a space from the sensor outlet to the case inlet is formed in the partition plate.

10. The particle concentration detection apparatus according to claim 9,

the communication section is formed in a portion of the partition plate (214) on the sensor case (52) side of the center of the air-conditioning case (21) and the sensor case (52).

11. The particle concentration detection apparatus according to claim 3,

the sensor housing has:

a first protrusion (531) that protrudes toward the sensor flow path side and guides air in the vehicle interior from the sensor inlet port to the inside of the sensor case; and

a second protrusion (532) that protrudes toward the sensor flow path side and guides air in the vehicle interior from inside the sensor case to the sensor flow outlet,

the sensor inlet is formed on a surface of the first protruding portion on a lower side in a vertical direction, and the sensor outlet is formed on a surface of the second protruding portion on a lower side in a vertical direction.

12. The particle concentration detection apparatus according to claim 4,

a rib (216) that blocks the air flow of the air outside the vehicle compartment flowing through the air passage is formed in the case member,

steps are provided between the case outlet and the rib and between the case inlet and the rib.

13. The particle concentration detection apparatus according to claim 12,

comprises a door member (22) for opening and closing an external air introduction port (242) for introducing air outside the vehicle compartment into the air passage,

the rib is configured as a sealing member for sealing a gap between the door member and the outside air introduction port.

14. The particle concentration detection apparatus according to claim 4,

a louver-shaped louver (215) is disposed on at least one of the case outlet, the case inlet, the sensor inlet, and the sensor outlet.

15. The particle concentration detection apparatus according to claim 4,

the inside of the sensor flow path has a labyrinth structure in which the internal space of the sensor flow path is formed in a labyrinth shape.

16. The particle concentration detection apparatus according to claim 4,

the sensor inlet is disposed above the case outlet in the vertical direction, and the sensor outlet is disposed above the case inlet in the vertical direction.

17. The particle concentration detection apparatus according to claim 4,

filters (61, 62) are disposed on at least one of the casing outlet and the casing inlet.

18. The particle concentration detection apparatus according to any one of claims 1 to 17,

filters (63, 64) are disposed on at least one of the sensor inlet and the sensor outlet.

19. The particle concentration detection apparatus according to any one of claims 1 to 18,

the air supply device is provided with an air supply fan (53) which introduces air outside the vehicle interior from the sensor inlet port into the sensor housing and blows air outside the vehicle interior from the sensor outlet port to the air passage.

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