JP4062092B2 - Air conditioner for vehicles - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicle air conditioner that adjusts the temperature of air blown from a face air outlet in the bi-level mode by the opening degree of a cold air bypass door.
[0002]
[Prior art]
In a conventional vehicle air conditioner, a bi-level mode in which air is blown from the upper and lower air outlets of the face air outlet and the foot air outlet to an occupant in an intermediate temperature season such as spring or autumn can be selected. The temperature of the upper and lower outlets is the air mix door after passing through the cooling heat exchanger, and the air volume ratio between the hot air passage passing through the heating heat exchanger and the first cold air passage bypassing the heating heat exchanger. The temperature of the blown air is adjusted by adjusting the value. In addition, there is a device that allows the head cold foot heat by adding a temperature difference to the air at the upper and lower outlets by the second cold air passage that directly guides the air after passing through the cooling heat exchanger to the face opening. The temperature difference between the upper and lower outlets is adjusted by the opening degree of the cold air bypass door that changes the opening area of the second cold air passage.
[0003]
In the vehicle air conditioner that realizes the temperature difference in this way, the face target value (head set temperature signal) calculated from the amount of solar radiation and the set temperature set by the occupant in the cold air bypass door in the bi-level mode Is known to change the air volume of the second cold air passage (see, for example, Patent Document 1).
[0004]
[Patent Document 1]
Japanese Patent Publication No. 6-20809
[0005]
[Problems to be solved by the invention]
However, if the opening of the air mix door changes during the execution of the bi-level mode, the amount of air passing through the second cold air passage also changes, so that the air blown out from the face opening on the downstream side of the air flow in the second cold air passage It was difficult to adjust the temperature to the target temperature. For this reason, an air conditioner that controls the opening degree of the cold air bypass door by installing a temperature sensor in the vicinity of the face air outlet and feeding back the air temperature of the face air outlet to the control device is known. However, since such an air conditioner needs an additional temperature sensor, it has caused an increase in the manufacturing cost of the vehicle air conditioner.
[0006]
In view of the above problems, the present invention does not detect the temperature in the vicinity of the face outlet and feeds it back to the control unit, and regardless of the change in the air volume of the second cold air passage based on the change in the air mix door opening. An object is to satisfactorily control the air temperature at the face outlet in the bi-level mode.
[0007]
[Means for Solving the Problems]
To achieve the above object, according to the first aspect of the present invention, the cooling heat exchanger (12) for cooling the blown air flowing toward the vehicle interior, and the air flow downstream side of the cooling heat exchanger (12). A heating heat exchanger (13) for heating the cold air that has passed through the cooling heat exchanger (12), and a first cold air passage (18) through which the cold air flows bypassing the heating heat exchanger (13) (18) ), The air mix door (15) for adjusting the air volume ratio between the hot air passing through the heating heat exchanger (13) and the cold air passing through the first cold air passage (18), and the air mix door (15) Provided on the downstream side of the air flow, provided on the downstream side of the air flow of the face opening (27) and the air mix door (15) that blows air toward the passenger's upper body in the passenger compartment, and the air is provided at the feet of the passenger in the passenger compartment. Foot opening (32) that blows out and cooling A second cold air passage (33) that sends the cold air immediately after the heat exchanger (12) directly to the face opening (27), bypassing the heating heat exchanger (13) and the air mix door (15); A cold air bypass door (34) for adjusting the air volume ratio of the cold air flowing through the cold air passage (33) and adjusting the temperature of the air blown from the face opening (27), the face opening (27) and the foot opening; (32) and at least a bi-level mode in which a temperature difference between the temperature of the air blown from the face opening (27) and the temperature of the air blown from the foot opening (32) can be set. In the bi-level mode, the temperature difference is maximized by fully opening the cold air bypass door (34), and at least the maximum value of the temperature difference (ΔTmax) is at least the air mix door. Calculate based on the input information value including the opening degree of (15), and calculate the target opening degree of the cold air bypass door (34) by the ratio of the target value (ΔT) of the temperature difference and the maximum value (ΔTmax) of the temperature difference. Then, the cold air bypass door (34) is controlled.
[0008]
By the way, the temperature of the blown air from the face opening (27) in the bilevel mode can be lowered by increasing the flow rate of the air from the second cold air passage (33). In this way, the temperature of the air blown from the face opening (27) is made lower than the temperature of the air blown from the foot opening (32), and a temperature difference is given to the temperature of the air blown from the upper and lower outlets. Can do. And the maximum value (ΔTmax) of the temperature difference between the upper and lower outlets is the air volume ratio of the cold air flowing through the second cold air passage (33) when the opening of the cold air bypass door (34) is fully open, the temperature of the cold air, It depends on the temperature of the air blown from the foot opening (32).
[0009]
As in the first aspect of the invention, the air volume ratio of the cold air flowing through the second cold air passage (33) when the opening of the cold air bypass door (34) is fully open is based on the opening of the air mix door (15). Thus, the air volume ratio of the second cold air passage (33) can be accurately calculated regardless of the opening degree of the air mix door (15). It can be calculated how low the temperature of the air blown from the face opening (27) can be calculated from the information value including the air volume ratio of the second cold air passage (33).
[0010]
And the target opening degree of the cold wind bypass door (34) is calculated from the ratio of the maximum value (ΔTmax) of the temperature difference between the upper and lower outlets and the target value (ΔT) of the temperature difference to control the cold wind bypass door (34). Therefore, the temperature of the air blown from the face opening (27) can be accurately controlled. Therefore, the temperature of the air blown from the face opening (27) is not detected by the temperature sensor, and the air volume of the second cold air passage (33) is changed due to the change of the air mix door (15) opening degree. Regardless, the temperature of the air blown from the face opening (27) in the bi-level mode can be controlled well.
[0011]
According to a second aspect of the present invention, in the first aspect, in addition to the opening degree of the air mix door (15), the foot blowing temperature correlated with the temperature of the blowing air from the foot opening (32) as the input information value. It is characterized by including a cold air temperature information value correlated with the information value and the temperature of the cold air immediately after passing through the cooling heat exchanger (12).
[0012]
According to this, the temperature of the blown air from the foot opening (32) can be obtained from the information value correlated with the temperature of the blown air from the foot opening (32). Then, from the cold air temperature obtained from the cold air temperature information value correlated with the air flow rate ratio of the second cold air passage (33) and the cold air temperature immediately after passing through the cooling heat exchanger (12), the face It is possible to calculate how much the air blown from the opening (27) can be lowered compared to the temperature of the air blown from the foot opening (32).
[0013]
As in the third aspect of the present invention, in the second aspect, the foot blowing temperature information value is a target temperature (TAO) of the blowing air into the passenger compartment.
[0014]
As in the invention described in claim 4, in any one of claims 1 to 3, the target value (ΔT) of the temperature difference is set to at least one of a target temperature (TAO), an amount of solar radiation, and an outside air temperature. The calculation is performed based on the input information value.
[0015]
According to this, since the target value (ΔT) of the temperature difference is calculated based on at least one input information value among the target temperature (TAO), the amount of solar radiation, and the outside air temperature that correlates with the passenger's temperature sensation, Closer to finer control. For example, when the amount of solar radiation is large, the temperature on the passenger's upper body side in the passenger compartment increases, so that the temperature difference target value (ΔT) can be increased to approach the passenger's sense of warmth. In addition, when the outside air temperature is high, the occupant wants cold air on the upper body side, so that the temperature difference target value (ΔT) can be increased to approach the occupant's warm feeling.
[0016]
According to a fifth aspect of the present invention, in the fourth aspect, the vehicle speed is added to the input information for calculating the temperature difference target value (ΔT), and the temperature difference target value (ΔT) is decreased as the vehicle speed increases. It is characterized by doing.
[0017]
According to this, the vehicle and the outside air exchange heat, and as the vehicle speed increases, the amount of heat exchange with the outside air increases, so the vehicle temperature approaches the outside air temperature. For this reason, the target value (ΔT) close to the passenger's sense of warmth can be obtained by adding the vehicle speed to the calculation information.
[0018]
According to a sixth aspect of the present invention, in the first to fifth aspects, a blow mode setting means (29) for opening and closing the face opening (27) and the foot opening (32) is provided, and the bi-level mode is a blow mode setting means. At least a plurality of bi-level modes in which the air volume ratio between the air volume of the air blown from the face opening (27) and the air volume of the air blown from the foot opening (32) are different can be set by the opening degree of (29). And the maximum value (ΔTmax) of the temperature difference is calculated according to the opening degree of the blowing mode setting means (29) to control the cold air bypass door (34).
[0019]
According to this, the vehicle air conditioner calculates the maximum value (ΔTmax) of the temperature difference according to the opening degree of the blowing mode setting means (29). For this reason, the maximum value (ΔTmax) of the temperature difference can be accurately calculated regardless of the change in the air volume ratio of the cold air flowing through the second cold air passage (33) by the plurality of bi-level modes.
[0020]
As in the seventh aspect of the present invention, in the sixth aspect, the plurality of bilevel modes includes at least an air volume of air blown from the face opening (27) and an air volume of air blown from the foot opening (32). Compared with the first bi-level mode and the first bi-level mode in which the air volume ratio is substantially the same, the air volume of the air blown from the face opening (27) is increased, and the air blown from the foot opening (32). And a second bi-level mode in which the air volume is reduced.
[0021]
As in the eighth aspect of the invention, in any one of the first to seventh aspects, the temperature correction means (1) is provided in the passenger compartment for occupant operation and corrects the target value (ΔT) of the temperature difference. 52), the temperature of the air blown from the face opening (27) can be corrected.
[0022]
In addition, the code | symbol in the bracket | parenthesis of each said means shows the correspondence with the specific means as described in embodiment mentioned later.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
Hereinafter, an embodiment of the present invention will be described with reference to FIG. The indoor unit portion of the vehicle air conditioner according to the present embodiment is roughly divided into two parts: an air conditioning unit 10 and a blower unit (not shown) that blows air to the air conditioning unit 10.
[0024]
The air conditioning unit 10 is disposed at a substantially central portion in the vehicle width (left and right) direction inside the instrument panel (not shown) in the front of the vehicle interior. The air conditioning unit 10 part is arranged in the mounting direction indicated by the arrows in FIG. 1 with respect to the front-rear direction and the vertical direction of the vehicle at a substantially central portion inside the instrument panel in the vehicle interior.
[0025]
On the other hand, the blower unit (not shown) is arranged offset from the center part to the passenger seat side in the inside of the instrument panel in the front part of the passenger compartment. As is well known, the blower unit includes an inside / outside air switching box that switches between outside air (outside air in the vehicle interior) and inside air (inside air inside the vehicle), and a centrifugal blower that sucks and blows air through the inside / outside air switching box.
[0026]
The air conditioning unit 10 has an air conditioning case 11 made of resin, and an air passage through which air flows into the vehicle interior is formed inside the air conditioning case 11.
[0027]
The air conditioning case 11 includes an evaporator 12 that forms a cooling heat exchanger and a heater core 13 that forms a heating heat exchanger. An air inlet space 14 is formed in a portion of the air conditioning case 11 closest to the vehicle front side. Blowing air flows into the air inlet space 14 from the scroll casing outlet of the centrifugal blower of the blower unit.
[0028]
In the air conditioning case 11, the evaporator 12 is disposed substantially vertically at a portion immediately after the air inlet space 14. As is well known, this evaporator 12 absorbs the latent heat of evaporation of the refrigerant in the refrigeration cycle from the conditioned air and cools the conditioned air. And the heater core 13 is arrange | positioned at predetermined intervals in the air flow downstream of the evaporator 12, ie, the vehicle rear side. Therefore, the air flowing into the air inlet space 14 in the air conditioning case 11 passes through the evaporator 12 and the heater core 13 in this order and flows from the vehicle front side to the vehicle rear side.
[0029]
Specifically, the heater core 13 is inclined and disposed such that the lower end portion thereof is located on the vehicle front side with respect to the upper end portion. The heater core 13 reheats the cold air that has passed through the evaporator 12, and hot water (engine cooling water) flows from a vehicle engine (not shown) into the heater core 13, and heats the air using this hot water as a heat source. .
[0030]
An air mix door 15 formed of a flat plate door is disposed between the evaporator 12 and the heater core 13 so as to be rotatable about a rotation shaft 16.
[0031]
The rotary shaft 16 of the air mix door 15 is disposed in the upper vehicle front direction of the upper end portion of the heater core 13. The air mix door 15 rotates in the vertical direction around the rotation shaft 16.
[0032]
The first cold air bypass passage 18 is disposed at an upper portion of the heater core 13 on the upstream side of the air flow, and the first hot air passage 17 is disposed on the lower portion of the heater core 13 on the upstream side of the air flow.
[0033]
A partition wall 19 having a contact surface at the tip of the air mix door 15 is disposed in the lower first warm air passage 17. The partition wall 19 is formed integrally with the air conditioning case 11, and is an air guide member that guides the air passing through the first hot air passage 17 and uniformly flows air into the entire vertical direction of the heater core 13. Play a role.
[0034]
The rotary shaft 16 of the air mix door 15 is rotatably supported by a bearing hole (not shown) on the wall surface of the air conditioning case 11. One end of the rotating shaft 16 projects outside the air conditioning case 11 and is connected to an actuator 41 via a link mechanism (not shown). The actuator 41 rotates the air mix door 15.
[0035]
The actuator 41 is constituted by an electric drive mechanism using a servo motor, and rotates the air mix door 15 with the rotational power of the servo motor. However, a manual type mechanism that directly rotates the air mix door 15 with the manual operation force of the occupant may be used as the temperature adjustment operation mechanism.
[0036]
The air mix door 15 passes through the first hot air passage 17 and the hot air (arrow a) heated by the heater core 13 and the first cold air passage 18 by adjusting the opening of the air mix door 15. The air volume ratio with the cold air (arrow b) is adjusted.
[0037]
On the other hand, in the air conditioning case 11, a wall surface 20 that extends in the vertical direction at a predetermined interval from the heater core 13 is integrally formed in the air conditioning case 11 at a downstream side (vehicle rear side) of the heater core 13. Yes. The wall surface 20 forms a second hot air passage 21 that extends upward immediately after the heater core 13. Here, the wall surface 20 is inclined toward the vehicle rear side along the inclination of the heater core 13. For this reason, similarly to the heater core 13, the second warm air passage 21 is inclined so that the lower end portion is located on the vehicle front side with respect to the upper end portion.
[0038]
The downstream side (upper side) of the second hot air passage 21 joins the downstream side of the first cold air passage 18 in the upper portion of the heater core 13 to form an air mixing portion 22 that mixes the cold air and the hot air. .
[0039]
The air mix door 15 constitutes temperature adjusting means for adjusting the air volume ratio between the cold air (arrow b) and the warm air (arrow a) flowing into the air mixing unit 22 to adjust the temperature of the air blown into the vehicle interior. .
[0040]
And in the upper surface part of the air-conditioning case 11, the defroster opening part 23 into which the air-conditioning air temperature-controlled from the air mixing part 22 flows in the intermediate part of the vehicle front-back direction is opening. The defroster opening 23 is connected to a defroster outlet on the upper surface of the instrument panel via a defroster duct (not shown), and conditioned air (mainly hot air) is blown from the defroster outlet toward the inner surface of the vehicle front window glass. .
[0041]
The defroster opening 23 is opened and closed by a flat defroster door 24. The defroster door 24 is rotatable about a rotation shaft 25, and switches the defroster opening 23 and the communication port 26 to open and close. The communication port 26 serves as a passage for flowing the conditioned air from the air mixing unit 22 to the face opening 27 and the foot introduction unit 28 side.
[0042]
The face opening 27 is provided on the upper surface portion of the air conditioning case 11 at a position on the vehicle rear side of the defroster opening 23. The face opening 27 is connected to a face air outlet (not shown) disposed on the upper side of the instrument panel via a face duct (not shown), and the conditioned air (mainly from the face air outlet toward the passenger's upper body side in the passenger compartment). Cold air) is blown out.
[0043]
The face opening 27 and the foot introduction part 28 are switched and opened and closed by a foot face switching door 29. The door 29 is constituted by a flat door that can rotate around a rotary shaft 30.
[0044]
Next, the foot opening 32 is provided below the face opening 27 in the air conditioning case 11. The foot opening 32 blows conditioned air (mainly warm air) to the feet of the front seat occupant through a foot duct (not shown).
[0045]
The defroster door 24 and the foot face switching door 29 constitute a blowing mode door for switching the blowing mode, and are operated in conjunction by the actuator 42 via a link mechanism (not shown).
[0046]
Further, a second cold air passage 33 and a cold air bypass door 34 are provided immediately after the upper portion of the evaporator 12. The second cold air passage 33 directly introduces the cold air that has passed through the upper part of the evaporator 12 into the upper part of the air mixing unit 22. The cold air bypass door 34 is composed of a plate door that can rotate about a rotation shaft 35 and is operated by an actuator 40 via a link mechanism (not shown).
[0047]
The cold air bypass door 34 increases the maximum cooling capacity by opening the second cold air passage 33 at the time of maximum cooling and increasing the amount of cool air blown into the vehicle interior. In addition, the second cold air passage 33 is opened in the first and second bi-level modes, and the cold air bypass door 34 is opened for the purpose of obtaining a head cold foot heat type vertical blowout temperature distribution.
[0048]
Next, the outline of the electric control unit of the first embodiment will be described. The control device 60 (hereinafter referred to as ECU 60) is a control means for controlling the air conditioning unit 10, and is well-known including a CPU, a ROM, a RAM, and the like. It consists of a microcomputer and its peripheral circuits. The ECU 60 stores a control program for air conditioning control in the ROM, and performs various calculations and processes based on the control program. On the input side of the ECU 60, an air conditioning sensor group 61 such as an inside air temperature sensor 43, an outside air temperature sensor 44, a solar radiation sensor 45, a post-evaporation temperature sensor 46 that detects the air temperature immediately after passing through the evaporator 12, and a cooling water temperature sensor 47. The detection signal is input. Further, on the input side of the ECU 60, operations in the vehicle interior such as a set temperature 48 for setting the temperature in the vehicle interior, a blowout mode switch 49, an inside / outside air changeover switch 50, a cold air bypass door opening correction 52 (hereinafter referred to as USDW52), etc. The operation signal of the air conditioning panel 62 which is a member is input.
[0049]
The air conditioning panel 62 is disposed near an instrument panel (not shown) in front of the driver's seat in the passenger compartment, and is provided as an operation member. The ECU 60 drives the actuators 40 to 42 and the like according to a predetermined control program based on the input of the operation signal of the operation member and the detection signal of the air conditioning sensor group 61.
[0050]
The blowout mode switch 49 outputs a signal for manually setting the face mode, the first bilevel mode, the second bilevel mode, the foot mode, the defroster mode, and the foot defroster mode as the blowout mode.
[0051]
In the face mode, the face opening 27 side is fully opened by the foot face switching door 29, the foot opening 28 side is closed, and the conditioned air is blown out only from the face blowout port (not shown) to the passenger's upper body in the passenger compartment. Mode.
[0052]
The first bi-level mode is a mode in which the face opening portion 27 and the foot introduction portion 28 side are substantially half-opened by the foot face switching door 29, and the conditioned air is blown to the occupant's upper body and the occupant's feet at substantially the same amount.
[0053]
The second bilevel mode is set by the foot face switching door 29 so that the face opening 27 side opens larger than the foot insertion portion 28 side as compared with the first bilevel mode. The air volume ratio of both openings is about 60% on the face side and about 40% on the foot side, and is a mode in which air-conditioned air is blown out to the upper body of the occupant and the feet of the occupant as in the first bi-level mode.
[0054]
The foot mode is a mode in which the face opening 27 side is closed, the foot introduction part 28 side is fully opened, and conditioned air is blown out from a foot outlet (not shown) to the occupant's feet.
[0055]
The defroster mode is a mode in which the defroster opening 23 is fully opened by the defroster door 24 and the conditioned air is blown to the inner surface of the window glass.
[0056]
The foot defroster mode is a mode in which the defroster opening 24 is substantially half-opened by the defroster door 24, the face opening 27 side is closed by the foot face door 29, and the conditioned air is blown to the window glass inner surface and the occupant's feet approximately by the same amount. is there.
[0057]
Next, the operation of the first embodiment in the above configuration will be described. FIG. 2 is a flowchart showing an outline of a main control program executed by the ECU 60 of the first embodiment. The control program of FIG. 2 is turned on by an ignition switch of a vehicle engine (not shown) and an auto switch 51 of an operation member. Is started, and control flags and various timers are initialized in step S100. Next, in step S110, the operation signals 48 to 50 and 52 of the operation member are obtained, and in step S120, input signals of the air conditioning sensors 43 to 47 for detecting the vehicle environment state that affects the air conditioning state in the passenger compartment are acquired. And stored in a RAM (not shown).
[0058]
Subsequently, in step S130, a target temperature of air blown into the vehicle interior, that is, a target blown air temperature TAO (hereinafter referred to as TAO) is calculated from the following equation 1 from the read value.
[0059]
[Expression 1]
TAO = Kset * Tset-Kr * Tr-Kam * Tam-Ks * Ts + C
Tset: set temperature set by the set temperature switch 48
Tr: temperature detected by the internal air temperature sensor 43
Tam: temperature detected by the outside air temperature sensor 44
Ts: detected value of the solar radiation sensor 45
Kset, Kr, Kam, Ks: Control gain
C: Constant for correction
Next, in step S140, the air volume of the blower is set based on TAO, the process proceeds to step S150, and the opening degree of the air mix door 15 is calculated.
[0060]
Subsequently, in step S160, the blowing mode is changed to the face mode, the first bi-level mode, the second blowing mode as the target blowing temperature TAO increases based on the characteristic chart of the blowing mode determination shown in FIG. The bi-level mode and foot mode are automatically switched sequentially. FIG. 3 is a characteristic diagram showing normal control of the air outlet by TAO. In FIG. 3, the face mode is selected when TAO is low, and the foot mode is selected when TAO is high.
Next, in step S170, the opening degree of the cold air bypass door 34 in the first and second bilevel modes is calculated. The calculation of the opening degree of the cold air bypass door 34 will be described later.
[0061]
Next, in step S180, the actuator 41 is driven based on the opening degree of the air mix door 15 set in step S150 by the ECU 60 to move the air mix door 15 to a predetermined position. At the same time, in accordance with the blowing mode set in step S160, the actuator 60 is driven by the ECU 60 to move the defroster door 24 or the foot face switching door 29 to a predetermined position. Furthermore, based on the opening degree of the cold air bypass door 34 set in step S170, the actuator 40 is driven to move the cold air bypass door 34 to a predetermined position. Then, the ECU 60 controls the blower and other devices (not shown) based on the air flow set in step S140 to execute the air conditioning automatic control, and returns to step S110 to repeat this automatic control.
[0062]
Subsequently, the calculation of the opening degree of the cold air bypass door 34 in step S170 will be described in detail with reference to FIGS.
[0063]
FIG. 4 is a flowchart showing an outline of a control program for setting the opening degree of the cold air bypass door 34 in the first and second bilevel modes.
[0064]
First, in step S171, a target value ΔT (° C.) of the temperature difference between the temperature of the air blown from the face opening 27 and the temperature of the air blown from the foot opening 32 in the first and second bilevel modes (hereinafter referred to as “T”). Face target temperature drop ΔT (° C.)). This face target temperature drop ΔT (° C.) is set according to TAO (° C.), solar radiation amount TS (W / m 2), vehicle speed SPD (Km / h), and outside air temperature TAM (° C.) from the chart of FIG. .
[0065]
Thus, in the chart of FIG. 5, the face target temperature drop ΔT (° C.) of the above-described temperature difference is set from the four input information values. In addition, each input information value in the chart of FIG. 5 is not used as a threshold value, and a numerical value selected from an input information value and an input information value close to the input information value are represented by a straight line. It is a numerical value complemented by tying. That is, when the input information value is TAO and is 5 ° C., it is between the case where TAO is 0 ° C. or lower and 25 ° C., and thus the case where ΔT ° C. and 25 ° C. corresponding to 0 ° C. or lower is applicable. It is for calculating proportionally from ΔT ° C. For example, if the vehicle speed SPD is 20 km / h, the outside air temperature TAM is −20 ° C., the solar radiation amount TS is 450 W / m 2, and only the TAO is changed, if the TAO is 25 ° C., the face target drop temperature ΔT (° C.) is 10 ° C., but when the TAO is 5 ° C., the face target temperature drop ΔT (° C.) does not become 10 ° C. When TAO is 5 ° C., the face target temperature drop ΔT (° C.) is 2 ° C. because it is proportionally calculated from the TAO temperature. In the chart of FIG. 5, when TAO is 0 ° C. or lower or 90 ° C. or higher, the face target temperature drop ΔT (° C.) is constant at 0 ° C., but when TAO is 0 ° C. or lower, that is, when the outside air temperature is high. It becomes the face mode. At this time, the opening% of the cold air bypass door 34 becomes 0% regardless of the face target temperature drop ΔT (° C.) in the first and second bilevel modes. The opening degree of the cold air bypass door 34 is 0% when the second cold air passage 33 is fully opened, and 100% is when the second cold air passage 33 is closed.
[0066]
In the chart of FIG. 5, as the amount of solar radiation TS increases, the face target drop temperature ΔT (° C.) also increases, and when the outside air temperature TAM increases, the face target drop temperature ΔT (° C.) also increases and the vehicle speed SPD increases. For example, the face target temperature drop ΔT (° C.) is set low.
[0067]
As described above, in step S171, the face target drop temperature ΔT (° C.) can be set based on the information on the elements related to the occupant's temperature sensation.
[0068]
Next, in step S172, the air volume ratio of the air flowing through the second cold air passage 33 (arrow c) corresponding to the opening degree of the air mix door 15 and the blowing mode when the opening degree of the cold air bypass door 34 is set to 100%. Calculated from FIG. It can be estimated how much the temperature of the air blown from the face opening 27 can be lowered by this air volume ratio. In addition, the vertical axis | shaft of FIG. 6 is the air volume ratio r (%) to the 2nd cold wind path | route 33, and a horizontal axis | shaft is the characteristic view made into opening degree SW of the air mix door 15. Further, the opening degree SW of the air mix door 15 is calculated based on the following formula 2 stored in advance in the ROM.
[0069]
[Expression 2]
SW = [(TAO−Te) / (Tw−Te)] × 100 (%)
Here, Tw is the temperature of the hot water flowing into the heater core 13 (water temperature) detected by the water temperature sensor, and Te is the temperature of the blown air from the evaporator 12 detected by the evaporator blown air temperature sensor. The vertical axis in FIG. 6 is from 0% to 100%, and indicates the air volume ratio% relative to the air volume sent by a blower (not shown). Further, the opening degree of the air mix door 15 on the horizontal axis in FIG. 6 is about −10% to 110%. The reason why the opening of the cold air bypass door 34 is in the range of about −10% to 110% is to prevent the air from leaking from the gap between the door and the sealing material (not shown). This is because the pressing is reflected in the control.
[0070]
Subsequently, in step S173, r%, which is the air volume ratio of the second cold air passage 33 when the opening degree of the cold air bypass door 34 is 100% calculated in step S172, TAO, and the temperature Te obtained by the after-evaporation temperature sensor 46. The maximum value ΔTmax of the temperature difference between the temperature of the air blown from the face opening 27 and the temperature of the air blown from the foot opening 32 (hereinafter referred to as the maximum face temperature drop ΔTmax (° C.)) is calculated from the following Equation 3. To do.
[0071]
[Equation 3]
ΔTmax = r / 100 × (TAO−Te)
Next, in step S174, the opening θ of the cold air bypass door 34 is calculated from the following equation 4 from the target value ΔT and the maximum face temperature drop ΔTmax (° C.), and the process returns to the main control program.
[0072]
[Expression 4]
θ = (1−ΔT / ΔTmax) × 100 (%)
Next, the function and effect of the first embodiment will be described.
[0073]
In the above flowchart, the face target temperature drop ΔT (° C.) and the face maximum temperature drop ΔTmax (° C.) can be calculated in step S173. Thereby, the temperature change amount of the blown air from the face opening 27 when the cold air bypass door 34 is opened can be estimated. Therefore, by calculating the opening degree of the cold air bypass door 34 from the ratio of both temperatures in step S174, the air blowout from the face opening 27 in the first and second bi-level modes without obtaining temperature information from the sensor. The air temperature can be controlled well.
[0074]
(Second Embodiment)
In the first embodiment, the face target temperature drop ΔT (° C.) is set using the chart of FIG. 5, but the correction setting USDW 52 for correcting the face target temperature drop ΔT (° C.) It may be installed on a panel and adjusted by the passenger.
[0075]
The USDW 52 can be adjusted to the maximum and minimum by manual adjustment by the occupant. When this adjustment is minimum, 0 V is sent to the ECU 60 as an adjustment signal. FIG. 7 is a chart showing ΔTVol, which is the correction temperature of the face target drop temperature ΔT (° C.) with respect to the input voltage by the USDW 52, and FIG. 8 shows the change of ΔTVol, which is the correction temperature corresponding to the voltage change of FIG. FIG. The vertical axis in FIG. 8 is the temperature for correcting the face target drop temperature ΔT (° C.), and the horizontal axis is the input voltage from the USDW 52.
[0076]
By providing a volume input for correction in the passenger compartment as in the second embodiment, the temperature of the air blown from the face opening 27 can be adjusted according to the preference of the occupant.
[0077]
(Other embodiments)
(1) In the vehicle air conditioners in the first and second embodiments, the opening degree of the air mix door 15 is calculated, and the air mix door 15 is driven by a servo motor to control the temperature of the blown air. In this embodiment, you may apply 1st, 2nd embodiment to the vehicle air conditioner which detects and controls the position of the air mix door 15 with a potentiometer.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram of a first embodiment of the present invention.
FIG. 2 is a flowchart showing an operation of an air conditioner ECU 60 of the first embodiment.
FIG. 3 is a characteristic diagram showing normal control of the air outlet by TAO.
4 is a flowchart showing a control process in step S170 of FIG.
5 is a chart showing setting of a target value ΔT of a temperature difference in step S171 in FIG.
FIG. 6 is a characteristic diagram showing the air volume ratio of the cold air bypass passage corresponding to the opening of the air mix door 15;
FIG. 7 is a chart showing a correspondence relationship between an input voltage and a correction temperature according to the second embodiment.
8 is a characteristic diagram showing a correspondence relationship between the input voltage and the correction temperature in FIG.
[Explanation of symbols]
12 ... Heat exchanger for cooling, 13 ... Heat exchanger for heating, 18 ... First cold air passage,
15 ... Air mix door, 27 ... Face opening.

Claims (8)

A cooling heat exchanger (12) that cools the air that flows toward the passenger compartment;
A heating heat exchanger (13) that is provided on the downstream side of the air flow of the cooling heat exchanger (12) and heats the cold air that has passed through the cooling heat exchanger (12);
A first cold air passage (18) through which the cold air flows bypassing the heating heat exchanger (13);
An air mix door (15) for adjusting the air volume ratio between the hot air passing through the heating heat exchanger (13) and the cold air passing through the first cold air passage (18);
A face opening (27) that is provided on the downstream side of the air flow of the air mix door (15) and blows out air toward the upper body of the passenger in the passenger compartment;
A foot opening (32) that is provided on the downstream side of the air flow of the air mix door (15) and blows air toward the passenger's feet in the passenger compartment;
A second cool air passage (directly passing the cool air just after the cooling heat exchanger (12) to the face opening (27) bypassing the heating heat exchanger (13) and the air mix door (15) ( 33)
A cold air bypass door (34) for adjusting a flow rate of cold air flowing through the second cold air passage (33) and adjusting a temperature of air blown from the face opening (27);
Air is blown out from the face opening (27) and the foot opening (32), and the temperature of the air blown from the face opening (27) and the temperature of the air blown from the foot opening (32) Bi-level mode that gives a temperature difference of at least can be set,
In the bi-level mode, the temperature difference is maximized by fully opening the cold air bypass door (34), and the maximum value (ΔTmax) of the temperature difference includes at least the opening of the air mix door (15). Calculated based on the information value,
The cold air bypass door (34) is controlled by calculating a target opening degree of the cold air bypass door (34) based on a ratio between the target value (ΔT) of the temperature difference and the maximum value (ΔTmax) of the temperature difference. A vehicle air conditioner. As the input information value, in addition to the opening degree of the air mix door (15), the foot blowing temperature information value correlated with the temperature of the blowing air from the foot opening (32) and the cooling heat exchanger (12 2. The vehicle air conditioner according to claim 1, further comprising a cold air temperature information value correlated with the temperature of the cold air immediately after passing through (). The vehicle air conditioner according to claim 2, wherein the foot blowing temperature information value is a target temperature (TAO) of the blowing air into the vehicle interior. The target value (ΔT) of the temperature difference is calculated from at least one input information value among the target temperature (TAO), the amount of solar radiation, and the outside air temperature. The vehicle air conditioner described in 1. Vehicle speed is added to the input information value for calculating the target value (ΔT) of the temperature difference,
The vehicle air conditioner according to claim 4, wherein the target value (ΔT) of the temperature difference is lowered as the vehicle speed increases. A blowing mode setting means (29) for opening and closing the face opening (27) and the foot opening (32),
In the bi-level mode, the air volume ratio between the air volume of the air blown from the face opening (27) and the air volume of the air blown from the foot opening (32) differs depending on the opening of the blow mode setting means (29). Multiple bi-level modes can be set at least,
6. The cold air bypass door (34) is controlled by calculating the maximum value (ΔTmax) of the temperature difference according to the opening of the blow mode setting means (29). The vehicle air conditioner as described in any one. The plurality of bi-level modes is a first bi-level mode in which at least the air volume ratio between the air volume of the air blown from the face opening (27) and the air volume of the air blown from the foot opening (32) is substantially the same. When,
A second bi-level mode in which the air volume of the air blown from the face opening (27) is increased and the air volume of the air blown from the foot opening (32) is reduced compared to the first bi-level mode; The vehicle air conditioner according to claim 6, wherein the vehicle air conditioner is configured as described above. The temperature correction means (52) provided in the said vehicle interior so that a passenger | crew can operate and correct | amends the said target value ((DELTA) T) of the said temperature difference is provided as described in any one of Claim 1 thru | or 7 characterized by the above-mentioned. The vehicle air conditioner described.

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