JP2010167895A - Air conditioner for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air conditioner for a vehicle capable of removing and preventing fogging, even on condition that fogging occurs to window glass, by newly adding a mode capable of blowing air from all blowoff ports. <P>SOLUTION: This air conditioner includes a vapor compression type refrigerating cycle, a defroster blowoff port for removing and preventing fogging on an internal surface of the window glass, a vent blowoff port for blowing air to the upper half of the body of an occupant, and a foot blowoff port for blowing air to feet of the occupant, to control blowing of temperature-conditioned air into a cabin. In the air conditioner, a defroster bi-level mode for blowing air from all the blowoff ports and a defroster vent mode for blowing air from the defroster blowoff port and the vent blowoff port are added. By setting the added modes during a condition in which the temperature of the window glass becomes lower than in-cabin dew point temperature and outside air dew point temperature, fogging on the window glass can be properly removed and prevented. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vehicle air conditioner capable of improving safety by removing fogging and preventing fogging of a vehicle window glass.

  In order to perform anti-fogging control of a vehicle window glass, conventionally, as disclosed in, for example, Patent Document 1, the refrigerant target calculated by the first, second, and third target evaporation temperature calculating means is used. By determining the evaporator temperature control method for the optimal temperature control of the blowout into the passenger compartment with the lowest evaporation temperature as the evaporation temperature control value, it is possible to prevent window fogging and reduce power consumption. We are trying to optimize the thermal comfort.

  However, in such a vehicle air conditioner, the window glass is fogged when the vehicle interior is below a certain temperature and above a certain humidity due to the rainy season, summer rain, heavy rain, and winter snow. It may end up. Even under such a condition that the window glass is fogged, when the air outlet mode is switched to the automatic control mode, the air outlet mode is switched based on signals from various sensors such as the outside air temperature and the vehicle interior target set temperature. Since the defroster mode (DEF mode) which blows out the temperature-controlled air from the vicinity of the window glass located at the front is not executed, there is a problem that fogging cannot be prevented. In addition, when the passenger gets into the vehicle from outside the passenger compartment, the passenger compartment may require vent mode (VENT mode) because the passenger compartment temperature is low. May be selected. Therefore, there is also a problem that there is a possibility that the comfort of the passenger is significantly impaired.

JP 2002-002267 A

  Therefore, an object of the present invention is to add a mode capable of blowing air from all the outlets and to use a control method as described in Patent Document 1 above, and fogging occurs in the window glass. An object of the present invention is to provide a vehicle air conditioner that can remove fogging and prevent fogging under such conditions.

  In particular, a means for estimating or detecting the temperature of the window glass is provided, and a mode in which air can be blown from all outlets has been newly added, so that the dew point inside and outside the vehicle can cause fogging on the window glass. Providing a vehicle air conditioner that can properly remove fogging and prevent fogging even under conditions where the glass temperature is lower than the temperature, prevent the passenger's safety from being lowered due to fogging the window glass, And it makes it a subject to maintain comfort in a vehicle.

  In order to solve the above problems, a vehicle air conditioner according to the present invention includes a vapor compression refrigeration cycle having a refrigerant compressor, a radiator, an expansion mechanism, and an evaporator, and removes and prevents fogging on the inner surface of the window glass. A defroster outlet, a vent outlet that blows out toward the upper body of the occupant, and a foot outlet that blows out toward the occupant's feet, and blows temperature-controlled air into the passenger compartment by air volume control means and air distribution mode switching means In the vehicle air conditioner that can control the defroster-by-level mode (hereinafter sometimes referred to as DEF-B / L mode) for blowing air from all the outlets, the defroster outlet and the vent It is characterized by the addition of a defroster vent mode (hereinafter sometimes referred to as DEF-VENT mode) for blowing air from the air outlet.

  In such a vehicle air conditioner according to the present invention, even when the air outlet mode is switched to the automatic control mode, the DEF-B / L mode or the DEF-VENT mode is selected depending on the environmental conditions at that time. It is possible to switch, and even under the condition that the DEF mode that blows temperature-controlled air from the defroster outlet is not executed in the conventional control, it is possible to blow air from the defroster outlet, thereby removing the fogging of the window glass and fogging Prevention will be achieved appropriately.

  In particular, when the bi-level mode or the vent mode is selected by the air outlet mode automatic switching means, the defroster-by-level mode or the defroster vent is selected according to the vehicle interior dew point temperature or the outside air dew point temperature and the window glass temperature. By controlling to be in the mode, it is possible to appropriately remove fogging and prevent fogging of the window glass even under conditions where the temperature of the window glass is lower than the vehicle interior dew point temperature or the outside air dew point temperature.

  The vehicle interior dew point temperature can be calculated by the vehicle interior dew point temperature calculation means using the evaporator outlet air temperature or the vehicle interior humidity and vehicle interior temperature detected by the vehicle interior humidity sensor.

  The outside air dew point temperature can be calculated by the outside air dew point temperature calculating means using the outside air humidity detected by the outside air humidity sensor and the outside air temperature detected by the outside air temperature sensor.

  The temperature of the window glass can be detected by a glass temperature sensor. It is also possible to estimate the temperature of the window glass from at least one of the outside air temperature and / or the amount of solar radiation.

Switch to DEF-B / L mode or DEF-VENT mode. For example, it is performed as follows.
Bi-level mode is selected, and the vehicle interior dew point temperature (Tindew) and window glass temperature (Tg)
Tindew> Tg
When this relationship is established, the air distribution mode can be switched to the defroster-by-level mode by the air distribution mode automatic switching means.

In addition, vent mode is selected, and the vehicle interior dew point temperature (Tindew) and window glass temperature (Tg) are Tindew> Tg
When this relationship is established, the air distribution mode can be switched to the defroster / vent mode by the air distribution mode automatic switching means.

In addition, the bi-level mode is selected, and the outside dew point temperature (Tambdew) and the window glass temperature (Tg)
Tambdew> Tg
When this relationship is established, the air distribution mode can be switched to the defroster-by-level mode by the air distribution mode automatic switching means.

In addition, vent mode is selected, and the outside dew point temperature (Tambdew) and window glass temperature (Tg) are Tambdew> Tg
When this relationship is established, the air distribution mode can be switched to the defroster / vent mode by the air distribution mode automatic switching means.

  By switching the air distribution mode by such an air distribution mode automatic switching means, the temperature of the window glass is lower than the dew point temperature in at least one of the inner surface side or the outer surface side, and the window glass may be fogged. At that time, the air blowing from the defroster outlet is performed, and thereby, the fogging of the window glass and the prevention of fogging are reliably and automatically achieved. In addition, at this time, since the bi-level mode or the vent mode is also executed, the comfort of the passenger in the vehicle is well maintained.

  Thus, according to the vehicle air conditioner according to the present invention, the DEF-B / L mode and the DEF-VENT mode are added to the air outlet mode automatic selection means of the conventional vehicle air conditioner, and the vehicle interior dew point temperature is further added. By controlling the air outlet mode using the relationship between the ambient air dew point temperature and the window glass temperature, it is possible to prevent the window glass from fogging even if there is a sudden change in humidity due to changes in environmental conditions. The safety of the vehicle can be ensured, and the passenger comfort can be improved.

It is a schematic block diagram of the vehicle air conditioner which concerns on one embodiment of this invention. It is a control characteristic figure which shows an example of the control form in this invention about the relationship between target blowing temperature and glass temperature. It is a flowchart which shows an example of the control at the time of defroster bilevel mode selection in this invention. It is a flowchart which shows an example of the control at the time of defroster vent mode selection in this invention.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 mainly shows mechanical components in a vehicle air conditioner according to an embodiment of the present invention, and shows a state in a defroster-by-level mode. This vehicle air conditioner includes an air conditioning unit 1 and a vapor compression refrigeration cycle 2. The vapor compression refrigeration cycle 2 is driven via an electromagnetic clutch 3 or the like by a vehicle engine (not shown, but another drive source such as an electric motor is also possible) as a drive source, and compresses the refrigerant. The variable capacity compressor 4, a radiator 5 (for example, a condenser) that cools the refrigerant by heat exchange between the high-temperature and high-pressure refrigerant discharged from the compressor 4 and external air, and the refrigerant that flows out of the radiator 5 are insulated. An expansion mechanism 6 (expansion valve) that expands, and an evaporator 7 that evaporates the refrigerant from the expansion mechanism 6 and that is disposed in the ventilation duct 8 of the air conditioning unit 1 and cools the conditioned air sent thereto. The refrigerant flowing out of the evaporator 7 is sent to the compressor 4 and compressed again.

  On the entrance side of the ventilation duct 8, the inside / outside air switching for switching the intake air between the outside air (inside air) introduced from the outside air introduction port 9 side and the inside air (inside air) introduced from the inside air introduction port 10 side. A damper 11 is provided. The introduced air is sucked in by the blower 12, supplied toward the evaporator 7, and cooled by heat exchange with the refrigerant by the evaporator 7. An evaporator outlet air temperature sensor 13 is provided on the outlet side of the evaporator 7, and a heater core 14 as a heater is provided on the downstream side of the evaporator 7. The ratio of the air passing through the heater core 14 and the bypassing air is adjusted by the air mix damper 15.

  The temperature-controlled air consists of a defroster (DEF) outlet 16 for removing and preventing fogging of the inner surface of the window glass, particularly the windshield, a vent (VENT) outlet 17 for blowing out toward the upper body of the passenger, and the feet of the passenger Can be blown out through a foot (FOOT) blowout port 18 that blows out toward the front, and the opening and closing of the blowout ports 16, 17, 18 can be controlled by the dampers 19, 20, 21. The air outlet control mode by opening / closing each damper 19, 20, 21 can be controlled by the air conditioning control device 22, and the air conditioning control device 22 can store the current state and the current air outlet mode. In the present invention, a defroster-by-level mode (DEF-B / L mode) in which air is blown from all the above-described air outlets 16, 17, 18 as a selectable air outlet mode as compared with the conventional air conditioning control, and a defroster A defroster vent mode (DEF-VENT mode) for blowing air from the air outlet 16 and the vent air outlet 17 is added.

  Although illustration is omitted, in the present embodiment, a sensor that can detect the temperature of the window glass is provided on the windshield. The glass temperature sensor may be in a side glass or a rear glass. Even when a glass temperature sensor cannot be mounted, it is possible to employ a method for estimating the temperature of the window glass based on information such as the outside air temperature and the amount of solar radiation. Further, a vehicle interior humidity sensor for detecting the humidity in the vehicle interior is provided. In addition, the vehicle interior humidity can be estimated from the vehicle interior dew point temperature and the vehicle interior temperature. In addition, an outside air humidity sensor for detecting the humidity of the outside air is provided. Alternatively, it is also possible to acquire information such as outside air humidity or precipitation from a meteorological satellite, the Meteorological Agency, or an electric power company via a receiving device mounted on the vehicle.

  In the above embodiment, the vapor compression refrigeration cycle uses a chlorofluorocarbon refrigerant, but may be a carbon dioxide refrigerant. The vapor compression refrigeration cycle is equipped with a clutch capable of controlling the drive of the compressor, but may be clutchless. In addition to the mechanical expansion valve, an electronic expansion valve, a temperature expansion valve, a differential pressure expansion valve, or the like may be used as the expansion mechanism of the compression refrigeration cycle. In the above-described vapor compression refrigeration cycle, an external variable capacity compressor that can change the capacity of the compressor by an external control signal is used. However, a fixed capacity compressor may be used. Further, the compressor of the vapor compression refrigeration cycle may be one driven by an engine, one driven by an electric motor, or a hybrid compressor that can be selectively or simultaneously driven by both drive sources.

  Each means for control in the vehicle air conditioner according to this embodiment as described above will be described with reference to the control characteristic example of FIG. In FIG. 2, the vertical axis represents the temperature, the horizontal axis represents the outside air temperature, and the characteristics of the target blowing temperature Toc and the glass temperature Tg are shown. In the figure, the broken line at the lower right indicates the target outlet temperature Toc, the broken line at the upper right indicates the glass temperature Tg, and the lines with arrows at both ends indicate the outlet mode under each temperature condition. In addition, the dew point temperature in the passenger compartment at a certain passenger compartment temperature and humidity is shown. Case 1 in the figure is when the vehicle interior dew point temperature (Tindew) or outside air dew point temperature (Tambdew) is higher, and Case 2 when vehicle interior dew point temperature (Tindew) or outside air dew point temperature (Tambdew) is lower. Is shown. When the glass temperature is lower than the vehicle interior dew point temperature, condensation occurs on the glass interior of the vehicle interior. When the glass temperature is lower than the outside air dew point temperature, condensation occurs on the outside of the glass.

Vehicle interior dew point temperature calculation means Since moisture is condensed in the evaporator by the introduction of outside air and the inside air, the vehicle interior dew point temperature (Tindew) is determined by the evaporator outlet air temperature (Tevaout). Further, since the humidification of the air after the evaporator is somewhat, there is almost no influence, so that the cabin air is maintained at the dew point temperature of the evaporator outlet air.
Tindew ≒ Tevaout
Alternatively, the humidity is detected by a vehicle interior humidity sensor, and the vehicle interior dew point temperature is calculated from the vehicle interior temperature (Tin) and the vehicle interior humidity (Hin).
Tindew = f (Tin, Hin)

Outside air dew point temperature calculation means The outside air dew point temperature (Tambdew) is calculated using the outside air temperature (Tamb) detected by the outside air temperature sensor and the outside air humidity (Hamb) detected by the outside air humidity sensor or acquired by the external information receiving means.
Tambdew = f (Tamb, Hamb)

Target blow temperature calculation means The target blow temperature (Toc) is calculated from the vehicle interior target set temperature (Tset), Tamb, solar radiation (RAD), and Tin.
Toc = f (Tset, Tamb, RAD, Tin)

Air outlet mode selection means The air outlet mode is selected according to the target air temperature (Toc). For example, the target air temperature is set to 25 ° C or lower for the VENT mode, 25 ° C to 40 ° C for the B / L mode, and 40 ° C or higher for the FOOT mode.
Mode = f (Toc)

DEF-B / L mode and DEF-VENT blowing mode selection means The outlet mode is automatically switched according to Toc, Tindew, Tambdew, and glass temperature (Tg). The standard for switching the outlet mode is automatically switched to the DEF-B / L mode when Tg is lower than Tindew or Tambdew when the outlet mode is B / L mode. When Tg is lower than Tindew or Tambdew when the outlet mode is VENT, the mode is automatically switched to DEF-VENT mode.
Tindew> Tg or Tambdew> Tg → DEF-B / L mode or DEF-VENT mode

External information receiving means Reference is made to meteorological data (precipitation, humidity, etc.) that can be acquired by a meteorological satellite, the Meteorological Agency, an electric power company, etc. via an external information receiving device that can receive external information mounted on the vehicle.

Next, a control example of switching to the DEF-B / L mode and the DEF-VENT blowing mode will be described with reference to FIGS.
Steps S1 and S11: Data necessary for each control means is acquired.
Steps S2-1, S2-2, S12-1, and S12-2: The target outlet temperature calculating means calculates the target outlet temperature (Toc), and the outlet mode selecting means determines the outlet mode. FIG. 3 shows an example in which the B / L mode is selected, and FIG. 4 shows an example in which the VENT mode is selected.
Steps S3-1, S3-2, S13-1, and S13-2: The vehicle interior dew point temperature calculating means detects or calculates the vehicle interior dew point temperature (Tindew). The outside air dew point temperature (Tambdew) is calculated by the outside air dew point temperature calculating means.
Steps S4 and S14: The outlet mode is selected by the outlet mode selection means. Further, when Tindew> Tg or Tambdew> Tg when the outlet mode is the B / L mode, the mode is switched to the DEF-B / L mode as shown in FIG. When Tindew> Tg or Tambdew> Tg when the outlet mode is the VENT mode, the mode is switched to the DEF-VENT mode as shown in FIG.

  In this way, when the glass temperature Tg becomes lower than the vehicle interior dew point temperature (Tindew) or the outside air dew point temperature (Tambdew), switching to the DEF-B / L mode or DEF-VENT mode allows the The air blowing appropriately prevents the window glass from fogging. Further, since the B / L outlet mode or the VENT outlet mode is maintained as it is, the comfort of the passenger in the vehicle is maintained.

  The present invention can be applied to any vehicle air conditioner equipped with DEF, VENT, and FOOT outlets.

DESCRIPTION OF SYMBOLS 1 Air conditioning unit 2 Vapor compression refrigeration cycle 3 Electromagnetic clutch 4 Compressor 5 Radiator 6 Expansion mechanism 7 Evaporator 8 Ventilation duct 9 Outside air inlet 10 Inside air inlet 11 Inside / outside air switching damper 12 Blower 13 Evaporator outlet air temperature sensor 14 Heater core 15 Air mix damper 16 Defroster outlet 17 Vent outlet 18 Foot outlet 19, 20, 21 Damper 22 Air conditioning control device

Claims (10)

  A refrigerant compressor, a radiator, an expansion mechanism, a vapor compression refrigeration cycle having an evaporator, a defroster outlet for removing and preventing fogging on the inner surface of the window glass, a vent outlet for blowing out toward the upper body of the occupant, In a vehicle air conditioner that includes a foot outlet that blows out toward the feet of an occupant and that can control the blowing of temperature-controlled air into the passenger compartment by means of air volume control means and air distribution mode switching means. An air conditioner for vehicles, wherein a defroster bilevel mode for blowing air and a defroster vent mode for blowing air from a defroster outlet and a vent outlet are added.   When the bi-level mode or the vent mode is selected by the air outlet mode automatic switching means, the defroster-by-level mode or the defroster-vent mode is selected according to the vehicle interior dew point temperature or the outside air dew point temperature and the window glass temperature. The vehicle air conditioner according to claim 1, which is controlled so as to become.   The vehicle air conditioner according to claim 2, wherein the vehicle interior dew point temperature calculating means calculates the vehicle interior dew point temperature using the evaporator outlet air temperature or the vehicle interior humidity and vehicle interior temperature detected by the vehicle interior humidity sensor. .   The vehicle air conditioner according to claim 2 or 3, wherein the outside air dew point temperature calculating means calculates the outside air dew point temperature using the outside air humidity detected by the outside air humidity sensor and the outside air temperature detected by the outside air temperature sensor.   The vehicle air conditioner according to any one of claims 2 to 4, wherein the temperature of the window glass is detected by a glass temperature sensor.   The vehicle air conditioner according to any one of claims 2 to 4, wherein the temperature of the window glass is estimated from at least one of an outside air temperature and / or an amount of solar radiation. Bi-level mode is selected, and the vehicle interior dew point temperature (Tindew) and window glass temperature (Tg)
Tindew> Tg
The vehicle air conditioner according to any one of claims 2 to 6, wherein the air distribution mode is switched to the defroster-by-level mode by the air distribution mode automatic switching means. Vent mode is selected, and the vehicle interior dew point temperature (Tindew) and window glass temperature (Tg)
Tindew> Tg
The vehicle air conditioner according to any one of claims 2 to 6, wherein the air distribution mode is switched to the defroster-vent mode by the air distribution mode automatic switching means. The bi-level mode is selected and the outside air dew point temperature (Tambdew) and the window glass temperature (Tg)
Tambdew> Tg
The vehicle air conditioner according to any one of claims 2 to 6, wherein the air distribution mode is switched to the defroster-by-level mode by the air distribution mode automatic switching means. The vent mode is selected and the outside dew point temperature (Tambdew) and the window glass temperature (Tg) are
Tambdew> Tg
The vehicle air conditioner according to any one of claims 2 to 6, wherein the air distribution mode is switched to the defroster-vent mode by the air distribution mode automatic switching means.

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