JP2019038324A - Vehicular air conditioner - Google Patents

Abstract

To provide a vehicular air conditioner capable of maintaining detection accuracy of particles by a particle detection section.SOLUTION: A vehicular air conditioner 10 includes: a particle detection section 300 for detecting particles in air; a blower 250 for sending air toward a cabin; and a control section 140 for controlling an operation of the blower 250. The particle detection section 300 includes: a light emitting section for emitting light via a first lens; and a light receiving section for receiving, out of the light emitted from the light emitting section, light scattered by the particles in the air passing through a detection area via a second lens. The control section 140 performs particle removal control that is control for increasing a flow rate of the air passing through the detection area by temporarily increasing the rotational frequency of the blower 250 and blowing off the particles accumulated on the first lens and the second lens by using the air.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to a vehicle air conditioner.

  The vehicle air conditioner adjusts the temperature of air taken in from the vehicle interior or the outside of the vehicle, and blows out the temperature-adjusted air (that is, conditioned air) toward the vehicle interior. The temperature of the air is adjusted by a heater core or an evaporator in the air conditioning unit, for example, as described in Patent Document 1 below.

JP 2008-24032 A

  The inventors of the present invention are studying to provide a vehicle air conditioner with a function of detecting the concentration of particles floating in the air (for example, fine particles such as PM2.5). For example, if the vehicle air conditioner is provided with a sensor for detecting particles and a part of the air drawn into the air conditioning unit from the vehicle interior flows through the sensor, the vehicle interior It becomes possible to measure particles in the air.

  As a sensor for detecting particles, one that optically detects particles is known. The sensor has a light emitting unit and a light receiving unit therein. The light emitting unit emits light through a lens toward a specific detection area in the sensor. The light receiving unit receives, through the lens, light scattered by particles in the air passing through the detection region among the light emitted from the light emitting unit. The sensor having such a configuration can detect the presence and concentration of particles in the air based on the amount of light received by the light receiving unit.

  In the sensor as described above, particles accumulate on the surface of the lens of the light emitting unit with the passage of time, and the amount of light emitted from the light emitting unit may decrease. Further, as time elapses, particles accumulate on the surface of the lens of the light receiving unit, and the amount of light received by the light receiving unit may decrease. If it will be in such a state, the detection accuracy of particles will fall.

  An object of the present disclosure is to provide a vehicle air conditioner capable of maintaining particle detection accuracy by a particle detector.

  The vehicle air conditioner (10) according to the present disclosure includes a particle detector (300) that detects particles in the air, a blower (250) that sends out air toward the passenger compartment, and a controller that controls the operation of the blower. (140). The particle detector is scattered by the light emitting part (310) that emits light through the first lens (311) and particles in the air that pass through the detection area (DA) among the light emitted from the light emitting part. A light receiving unit (320) that receives light through the second lens (321). The control unit is configured to increase the flow rate of air passing through the detection region by temporarily increasing the rotation speed of the blower, and to control the particles accumulated on the first lens and the second lens to be blown off by the air. Perform removal control.

  The vehicle air conditioner having such a configuration can remove particles deposited on the first lens and the second lens by performing particle removal control. The particle removal control is a control for increasing the flow rate of air passing through the detection region by temporarily increasing the number of rotations of the blower and blowing particles deposited on the first lens and the second lens by the air. . By such control, the surfaces of the first lens and the second lens are kept clean, so that the particle detection accuracy by the particle detector is maintained.

  According to the present disclosure, there is provided a vehicle air conditioner that can maintain the particle detection accuracy of the particle detector.

FIG. 1 is a diagram illustrating an overall configuration of a vehicle air conditioner according to a first embodiment. FIG. 2 is a diagram illustrating an internal configuration of a particle detection unit included in the vehicle air conditioner according to the first embodiment. FIG. 3 is a flowchart showing a flow of processing executed by the control device provided in the vehicle air conditioner according to the first embodiment. FIG. 4 is a flowchart showing a flow of processing executed by the control device provided in the vehicle air conditioner according to the second embodiment. FIG. 5 is a flowchart showing a flow of processing executed by the control device provided in the vehicle air conditioner according to the third embodiment.

  Hereinafter, the present embodiment will be described with reference to the accompanying drawings. In order to facilitate the understanding of the description, the same constituent elements in the drawings will be denoted by the same reference numerals as much as possible, and redundant description will be omitted.

  A vehicle air conditioner 10 according to the present embodiment will be described with reference to FIG. The vehicle air conditioner 10 is an apparatus for performing air conditioning in a vehicle interior of a vehicle (the whole is not shown). The vehicle air conditioner 10 includes an air conditioning case 200, a blower 250, a particle filter 240, a heat exchange unit 260, a particle detection unit 300, and a control device 100.

  The air conditioning case 200 is a tubular member for guiding the air to be air conditioned into the passenger compartment. Inside the air conditioning case 200, air flows in a direction from the left side to the right side in FIG. In the air conditioning case 200, an inside air introduction section 210, an outside air introduction section 220, a face duct 270, and a foot duct 280 are formed.

  The inside air introduction unit 210 is an introduction port for taking air inside the vehicle (inside air) into the air conditioning case 200. The outside air introduction unit 220 is an introduction port for taking air outside the vehicle compartment (outside air) into the air conditioning case 200. The inside air introduction part 210 and the outside air introduction part 220 are formed so as to line up in the upstream part of the air conditioning case 200.

  An inside / outside air switching door 230 is provided between the inside air introduction unit 210 and the outside air introduction unit 220. The inside / outside air switching door 230 is a door for switching between a state in which only the inside air introduction unit 210 is opened (FIG. 1) and a state in which only the outside air introduction unit 220 is opened. The state in which only the inside air introduction part 210 is opened is a state in which the inside air taken in from the passenger compartment is air-conditioned and blown into the passenger compartment, that is, an inside air circulation state. The state where only the outside air introduction part 220 is opened is a state where the outside air taken from outside the vehicle compartment is air-conditioned and blown out into the vehicle compartment, that is, an outside air circulation state. The operation of the inside / outside air switching door 230 is controlled by the control device 100 described later.

  Both the face duct 270 and the foot duct 280 are outlets for guiding conditioned air into the vehicle interior. The face duct 270 and the foot duct 280 are formed in the downstream portion of the air conditioning case 200. The face duct 270 is connected to a face outlet (not shown) for blowing air conditioned air toward the passenger's face. The foot duct 280 is connected to a foot outlet (not shown) for blowing conditioned air toward the feet of the passenger.

  A face door 271 is provided at the entrance of the face duct 270. When the face door 271 is in the open state as shown in FIG. 1, conditioned air is supplied from the face duct 270 toward the face outlet. Similarly, a foot door 281 is provided at the entrance of the foot duct 280. When the foot door 281 is in the open state, the conditioned air is supplied from the foot duct 280 toward the foot outlet. The operations of the face door 271 and the foot door 281 are controlled by the control device 100.

  For example, the downstream side of the face duct 270 may be branched into two, and one of them may be connected to a defroster outlet (not shown) formed in the vicinity of the window.

  The blower 250 is a blower for sending air toward the passenger compartment inside the air conditioning case 200. The rotational speed of the blower 250, that is, the amount of conditioned air blown from the vehicle air conditioner 10 is controlled by the control device 100.

  The particle filter 240 is a filter for removing particles contained in the air from the air passing through the air conditioning case 200. The particle filter 240 is provided at a position downstream of the inside air introduction unit 210 and the outside air introduction unit 220 and upstream of the blower 250. The “particles” here are fine particles such as PM2.5.

  The heat exchange unit 260 is a part that performs air conditioning by heat exchange with a refrigerant or the like. The heat exchanging unit 260 is provided at a position downstream of the blower 250 and upstream of the face duct 270 and the foot duct 280. The heat exchange unit 260 includes an evaporator for dehumidifying and cooling the air, a heater core for heating the air, an air mix door for adjusting the flow rate of air passing through these, (Shown) is provided. In addition, since a well-known thing can be employ | adopted as a structure of such a heat exchange part 260, the specific illustration and description are abbreviate | omitted.

  The particle detector 300 is a sensor for detecting particles in the air. As shown in FIG. 1, one end of the introduction pipe 290 is connected to the air conditioning case 200 at a position downstream of the particle filter 240 and upstream of the blower 250. The other end of the introduction pipe 290 is open to the vehicle interior. The particle detector 300 is provided at a position in the middle of the introduction tube 290. When the blower 250 is driven and air is flowing inside the air conditioning case 200, air flows also in the introduction pipe 290 due to the negative pressure generated on the air conditioning case 200 side. That is, an air flow is generated from the passenger compartment through the introduction pipe 290 into the air conditioning case 200. The particle detection unit 300 measures the concentration of particles contained in the air and transmits the concentration to the control device 100 using an electrical signal.

  The internal configuration of the particle detection unit 300 will be described with reference to FIG. The particle detection unit 300 includes a light emitting unit 310 and a light receiving unit 320 inside thereof. The light emitting unit 310 irradiates light that has flowed from the introduction tube 290 inside the particle detection unit 300. The light is emitted through the first lens 311 included in the light emitting unit 310. In the present embodiment, an LED is used as the light emitting unit 310. In FIG. 2, an alternate long and short dash line denoted by reference symbol LX1 indicates the optical axis of the light emitting unit 310. Hereinafter, the optical axis is also referred to as “optical axis LX1”. The light emitted from the light emitting unit 310 is irradiated toward the flowing air as shown by the arrows in FIG. A part of the light hits particles contained in the air (that is, particles to be detected) and is scattered.

  The light receiving unit 320 is an element that receives the scattered light as described above and generates a signal (specifically, voltage) corresponding to the amount of received light. The light is received through the second lens 321 included in the light receiving unit 320. In FIG. 2, an alternate long and short dash line with a symbol LX <b> 2 indicates the optical axis of the light receiving unit 320. Hereinafter, the optical axis is also referred to as “optical axis LX2”.

  The optical axis LX1 and the optical axis LX2 intersect each other at a position in the middle of the path through which air flows. A minute area including the intersecting point and the vicinity thereof is a detection area DA for detecting particles. The particle detection unit 300 is designed such that the light receiving unit 320 receives only light scattered by particles in the air passing through the detection area DA. Thereby, the detection of the particle | grains by the light-receiving part 320 is performed correctly. The particle detection unit 300 transmits a signal (specifically, voltage) based on the amount of light received by the light receiving unit 320 to the control device 100. The control device 100 can acquire the particle concentration in the air in the vehicle interior based on the signal.

  Returning to FIG. The control device 100 is a device for controlling the overall operation of the vehicle air conditioner 10. The control device 100 is configured as a computer system including a CPU, a ROM, a RAM, and the like. As already described, the control device 100 controls the operation of the inside / outside air switching door 230, the blower 250, and the like.

  Instead of such an aspect, an aspect in which the ECU that controls the entire vehicle has the function of the control device 100 may be employed. That is, the aspect which the control apparatus 100 which controls the vehicle air conditioner 10 is comprised as a part of ECU which controls the whole vehicle may be sufficient.

  In the vehicle on which the vehicle air conditioner 10 is mounted, various sensors are provided in addition to the particle detection unit 300, and signals from the respective sensors are input to the control device 100. FIG. 1 shows an in-vehicle camera 141 and a seating sensor 142 among these sensors.

  The in-vehicle camera 141 is a camera for taking a picture of the inside of the passenger compartment, and is a CMOS camera, for example. An image captured by the in-vehicle camera 141 is input to the control device 100 as image data. The control device 100 can grasp the presence or absence of an occupant in the passenger compartment, for example, by analyzing the image.

  The seating sensor 142 is a sensor for detecting whether or not an occupant is seated in a vehicle seat. The seating sensor 142 is provided in each seat of the vehicle. The control device 100 can determine whether or not an occupant is seated in each seat based on the signal transmitted from each seating sensor 142.

  The control device 100 includes a deposition determination unit 110, a deposition amount determination unit 120, an occupant determination unit 130, and a control unit 140 as functional control blocks.

  The accumulation determination unit 110 is a part that determines whether or not particles are accumulated on at least one surface of the first lens 311 and the second lens 321. If particles are deposited on any lens surface, the amount of light received by the light receiving unit 320 via the second lens 321 decreases, and the voltage output from the light receiving unit 320 decreases. The accumulation determination unit 110 determines whether particles are accumulated on at least one surface of the first lens 311 and the second lens 321 based on whether or not the voltage falls below a predetermined value.

  In addition, the aspect which the particle | grain detection part 300 determines by the self-diagnosis whether the particle | grains have accumulated on the surface of the 1st lens 311 grade | etc., May be sufficient. In this case, the accumulation determination unit 110 may determine whether or not particles are accumulated on the surface of the first lens 311 or the like by acquiring the determination result from the particle detection unit 300.

  The accumulation amount determination unit 120 is a portion that determines the amount of particles (hereinafter also referred to as “deposition amount”) accumulated on the surfaces of the first lens 311 and the second lens 321. As described above, when particles are deposited on the surface of the lens such as the first lens 311, the amount of light received by the light receiving unit 320 via the second lens 321 decreases, and the voltage output from the light receiving unit 320. Becomes lower. The accumulation amount determination unit 120 determines the accumulation amount on the surface of the first lens 311 and the like based on the decrease amount of the voltage.

  In addition, the aspect which the particle | grain detection part 300 determines by the self-diagnosis the deposition amount on the surface of the 1st lens 311 grade | etc., May be sufficient. In this case, the accumulation amount determination unit 120 may determine the accumulation amount by acquiring the determination result from the particle detection unit 300.

  The occupant determination unit 130 is a part that determines whether an occupant is present in the passenger compartment. The occupant determination unit 130 determines whether there is an occupant in the vehicle interior by analyzing, for example, an image of the vehicle interior captured by the in-vehicle camera 141. The occupant determination unit 130 can also make the above determination based on a signal transmitted from the seating sensor 142 of each seat.

  The control unit 140 is a part that controls the operations of the blower 250, the inside / outside air switching door 230, the face door 271, and the foot door 281. The control unit 140 controls the operation of each unit so that air conditioning in the vehicle interior is appropriately performed.

  By the way, when particles accumulate on the surface of the first lens 311 with the passage of time, the amount of light emitted from the light emitting unit 310 toward the detection area DA decreases. In addition, when particles accumulate on the surface of the second lens 321 as time passes, the amount of light received by the light receiving unit 320 decreases. If it will be in such a state, the detection accuracy of particles by particle detection part 300 will fall. Therefore, in the vehicle air conditioner 10 according to the present embodiment, the control device 100 executes the control described below, thereby preventing a decrease in detection accuracy due to particle accumulation.

  The contents of the control performed by the control device 100 will be described with reference to FIG. A series of processes shown in FIG. 3 are repeatedly executed by the control device 100 every time a predetermined control cycle elapses.

  In the first step S01, it is determined whether or not particles are deposited on at least one of the first lens 311 and the second lens 321. The determination is performed by the deposition determination unit 110 as described above. When it is determined that particles are not deposited on the first lens 311 or the like, the series of processes shown in FIG. If it is determined that particles are deposited on the first lens 311 or the like, the process proceeds to step S02.

  In step S02, it is determined whether an occupant is present in the passenger compartment. This determination is performed by the occupant determination unit 130 as described above. When it is determined that even one passenger is present in the passenger compartment, the series of processes shown in FIG. 3 is terminated. If no passenger is present in the passenger compartment, the process proceeds to step S03.

  In step S03, the control unit 140 sets the length of the control period. The “control period” is a period during which particle removal control described below is continued. Here, the accumulation amount is determined in advance by the accumulation amount determination unit 120, and the length of the control period is set based on the accumulation amount. Specifically, the control period is set longer as the determined accumulation amount is larger. The correspondence between the accumulation amount and the length of the control period may be set so that the length of the control period changes stepwise or may be set so as to change continuously. The correspondence relationship is stored in advance as a map in a storage device (not shown) included in the control device 100.

  In step S04 following step S03, particle removal control is started. The particle removal control is control for increasing the flow rate of air passing through the detection area DA by temporarily increasing the rotational speed of the blower 250. When the particle removal control is performed, the particles accumulated on the surfaces of the first lens 311 and the second lens 321 are blown away by the air having an increased flow rate. Thereby, the surface of the 1st lens 311 and the surface of the 2nd lens 321 are made into the clean state in which particle | grains have not accumulated.

  When the rotational speed of the blower 250 is increased by the process of step S04, the process proceeds to step S05. In step S05, it is determined whether or not the above control period has elapsed between the time point when the process of step S04 is started and the current time point. If the control period has not yet elapsed, the process of step S05 is repeatedly executed. That is, particle removal control is continued and the state where the rotation speed of the blower 250 is increasing is maintained.

  If the control period has elapsed in step S05, the process proceeds to step S06. In step S06, a process for ending the particle removal control is performed. Specifically, a process for returning the rotational speed of the blower 250 to the original rotational speed before the start of the particle removal control is performed. Thereafter, the series of processes shown in FIG.

  As described above, in the vehicle air conditioner 10 according to the present embodiment, when the deposition determining unit 110 determines that particles are deposited on the surface of the first lens 311 or the like, the control unit 140 performs the particle processing. Perform removal control. As a result, particles deposited from the surface of the first lens 311 and the like are removed, so that the surface is always kept clean. As a result, the detection accuracy of particles by the particle detection unit 300 is not lowered and is maintained with high accuracy.

  By the way, in the period when particle removal control is performed, the air volume of the conditioned air blown out from the vehicle air conditioner 10 into the vehicle interior increases. This may cause an uncomfortable feeling to the passengers in the passenger compartment. Therefore, as described above, the control unit 140 according to the present embodiment performs the particle removal control only when the occupant determination unit 130 determines that no occupant is present in the vehicle interior. This prevents unpleasant feelings for the passengers in the passenger compartment.

  The control unit 140 continues to perform particle removal control during a preset control period. Further, the length of the control period is set to be a length corresponding to the accumulation amount. Thereby, the particle removal control can be executed only in a minimum period necessary for blowing off the particles.

  A second embodiment will be described. Hereinafter, differences from the first embodiment will be mainly described, and description of points that are common to the first embodiment will be omitted as appropriate. The present embodiment is different from the first embodiment only in the contents of the processing executed by the control device 100.

  The contents of the processing executed by the control device 100 of this embodiment will be described with reference to FIG. The series of processing shown in FIG. 4 is executed in place of the series of processing shown in FIG.

  In the first step S11 of the process, as in step S01 of FIG. 3, it is determined whether or not particles are deposited on at least one of the first lens 311 and the second lens 321. When it is determined that particles are not deposited on the first lens 311 or the like, the series of processes shown in FIG. If it is determined that particles are deposited on the first lens 311 or the like, the process proceeds to step S12.

  In step S12, as in step S02 of FIG. 3, it is determined whether or not there is an occupant in the vehicle interior. If it is determined that even one passenger is present in the passenger compartment, the series of processes shown in FIG. 4 is terminated. If no passenger is present in the passenger compartment, the process proceeds to step S13.

  In step S13, particle removal control is started as in step S04 of FIG. As a result, the rotational speed of the blower 250 increases, and the particles deposited on the surface of the first lens 311 and the like are blown off and decreased.

  In step S14 following step S13, it is determined whether or not particles are deposited on at least one of the first lens 311 and the second lens 321 as in step S11. If particles are still deposited, the process of step S14 is repeated. That is, particle removal control is continued and the state where the rotation speed of the blower 250 is increasing is maintained.

  If it is determined in step S14 that particles are not deposited on either the first lens 311 or the second lens 321, the process proceeds to step S15. In step S15, similarly to step S06 in FIG. 3, a process for ending the particle removal control is performed. Thereby, the rotation speed of the blower 250 is returned to the original rotation speed. Thereafter, the series of processes shown in FIG.

  As described above, in the vehicle air conditioner 10 according to the present embodiment, the deposition determining unit determines that particles are not deposited on the surfaces of the first lens 311 and the second lens 321. In the meantime, the control unit 140 continues the particle removal control. That is, the particle removal control is not completed when the predetermined control period has elapsed, but is terminated when the particle is not deposited on the surface of the first lens 311 or the like. Thereby, it is possible to execute the particle removal control more efficiently (that is, in the minimum necessary period).

  A third embodiment will be described. Hereinafter, differences from the first embodiment will be mainly described, and description of points that are common to the first embodiment will be omitted as appropriate. This embodiment is also different from the first embodiment only in the contents of the processing executed by the control device 100.

  The contents of the process executed by the control device 100 of this embodiment will be described with reference to FIG. The series of processes shown in FIG. 5 is executed in place of the series of processes shown in FIG.

  In the first step S21 of the process, it is determined whether or not an occupant is present in the vehicle compartment, as in step S02 of FIG. If it is determined that even one passenger is present in the passenger compartment, the series of processes shown in FIG. 5 is terminated. If no passenger is present in the passenger compartment, the process proceeds to step S22.

  In step S22, it is determined whether or not a predetermined period has elapsed between the execution (starting time or completion) of the previous particle removal control and the current time. If the predetermined period has not yet elapsed, the series of processes shown in FIG. 5 is terminated. If the predetermined period has elapsed, the process proceeds to step S23.

  In step S23, particle removal control is started as in step S04 of FIG. As a result, the rotational speed of the blower 250 increases, and the particles deposited on the surface of the first lens 311 and the like are blown off and decreased.

  In step S24 following step S23, it is determined whether or not the control period has elapsed between the time point when the process of step S23 is started and the current time point. The “control period” in this embodiment is a period in which the length is set as a fixed value in advance. Instead of such an aspect, the length of the control period may be set each time based on the accumulation amount, as in the first embodiment.

  In step S24, if the control period has not yet elapsed, the process of step S24 is repeatedly executed. That is, particle removal control is continued and the state where the rotation speed of the blower 250 is increasing is maintained.

  In step S24, if the control period has elapsed, the process proceeds to step S25. In step S25, similarly to step S06 in FIG. 3, a process for ending the particle removal control is performed. Thereby, the rotation speed of the blower 250 is returned to the original rotation speed. Thereafter, the series of processing shown in FIG.

  As described above, in the vehicle air conditioner 10 according to the present embodiment, the particle removal control is executed every time a predetermined period set in advance elapses. As described above, the particle removal control may be periodically executed when there is no occupant regardless of whether particles are deposited on the surface of the first lens 311 or the second lens 321. Even if it is such an aspect, the effect similar to what was demonstrated in 1st Embodiment can be acquired.

  The present embodiment has been described above with reference to specific examples. However, the present disclosure is not limited to these specific examples. Those in which those skilled in the art appropriately modify the design of these specific examples are also included in the scope of the present disclosure as long as they have the features of the present disclosure. Each element included in each of the specific examples described above and their arrangement, conditions, shape, and the like are not limited to those illustrated, and can be changed as appropriate. Each element included in each of the specific examples described above can be appropriately combined as long as no technical contradiction occurs.

10: Vehicle air conditioner 140: Control unit 250: Blower 300: Particle detection unit 310: Light emission unit 311: First lens 320: Light reception unit 321: Second lens DA: Detection region

Claims (6)

A vehicle air conditioner (10) comprising:
A particle detector (300) for detecting particles in the air;
A blower (250) for sending air toward the passenger compartment;
A control unit (140) for controlling the operation of the blower,
The particle detector
A light emitting unit (310) that emits light through the first lens (311);
A light receiving unit (320) that receives, through the second lens (321), light scattered by particles in the air that pass through the detection region (DA) out of the light emitted from the light emitting unit. And
The controller is
Particles that control to increase the flow rate of air passing through the detection region by temporarily increasing the rotation speed of the blower and to blow off particles deposited on the first lens and the second lens by the air A vehicle air conditioner that performs removal control. A deposition determination unit (110) for determining whether particles are deposited on at least one of the first lens and the second lens;
The controller is
The vehicle air conditioner according to claim 1, wherein the particle removal control is performed when it is determined by the accumulation determination unit that particles are accumulated. An occupant determination unit (130) for determining whether there is an occupant in the passenger compartment;
The controller is
The vehicle air conditioner according to claim 1, wherein the particle removal control is performed when the occupant determination unit determines that no occupant is present in the vehicle interior.   The vehicle air conditioner according to any one of claims 1 to 3, wherein the control unit performs the particle removal control continuously for a predetermined period. A deposition amount determination unit (120) for determining a deposition amount that is an amount of particles deposited on the first lens and the second lens;
5. The vehicle air conditioner according to claim 4, wherein the control unit sets the predetermined period to be longer as the accumulation amount determined by the accumulation amount determination unit increases. A deposition determining unit that determines whether particles are deposited on at least one of the first lens and the second lens;
The controller is
The particle removal control is continuously performed until the accumulation determination unit determines that particles are not deposited on the first lens and the second lens. The vehicle air conditioner according to any one of the above.

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