JP2007125941A - Air conditioner for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air conditioner for a vehicle capable of obtaining stable air conditioning feeling that the head is cool and the feet are warm even in a case wherein the outside air temperature is low on a sunny day. <P>SOLUTION: In the blow-out mode of opening a face opening part 27, an auxiliary cold air bypass passage 17 is opened, and in the blow-out mode of closing other face opening 27, the auxiliary cold air bypass passage 17 is closed. With this structure, in the blow-out mode of opening the face opening part 27, concretely, in the face blow-out mode and the bi-level blow-out mode, the auxiliary cold air bypass passage 17 is opened, and a large temperature difference between the highest and the lowest can be secured in comparison with a current one, and even if the blow-out temperature at the feet is high, the relatively cold air can be obtained from the face blow-out opening. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a vehicle air conditioner that has a cold air bypass door and adjusts the temperature difference between the air temperature from the face opening and the air temperature from the foot opening by adjusting the opening thereof. In particular, the present invention relates to opening / closing control of the cold air bypass door.

  Conventionally, for example, as shown in Patent Document 1 below, a cold air bypass door is provided, and by adjusting the opening degree, the amount of cold air flowing from the auxiliary cold air bypass passage to the face opening is adjusted to adjust the blown air temperature, and the face opening From the part, mainly blown out cold air, blown out mainly warm air from the foot opening, so-called bi-level blowing mode that obtains the state of head cold foot heat, face blowing mode that blows cold air only from the face opening, etc. What can set various blowing modes is known.

Further, in Patent Document 2 below, there is one in which a cold air bypass door is used to establish temperature control, and the driving of the cold air bypass door is interlocked with the driving of the blowing mode switching door. Patent Document 3 below describes that a cold air bypass door is used to obtain a temperature difference between the upper and lower sides, but does not describe a specific method.
Patent 2531274 JP 11-48749 A Japanese Patent Laid-Open No. 2003-21934

  Conventionally, even in a heating state in which warm air is blown from the foot outlet to the feet in winter or the like, there is a case where relatively cool cold air is desired from the face outlet to the head and chest when the sunlight is strong. However, even in the head cold foot type bi-level blowing mode, if the temperature difference between the upper and lower sides is small, there is a problem that the warm air blows out from the face outlet and the air conditioning feeling is poor in conjunction with the high outlet temperature.

  Conventionally, there is a technique for adjusting the blown air temperature by providing an auxiliary cold air bypass passage and adjusting the amount of cold air flowing to the face opening by adjusting the opening and closing of the cold air bypass door disposed in the auxiliary cold air bypass passage. Since the cold air bypass door is opened and closed separately from the blow mode switching door, there is a problem in that it affects the balance of the air flow flowing through each part and affects the air conditioning feeling of other parts that are not intended.

  The present invention has been made in view of the above-described problems of the prior art, and its object is to provide a vehicle air conditioner that can obtain a stable head-and-foot air-conditioning feeling even when there is solar radiation at a low outside temperature. To provide an apparatus.

In order to achieve the above object, the present invention employs technical means described in claims 1 to 5. That is, in the invention according to claim 1, an air conditioning case (10) that forms an air passage,
A heater core (20) disposed in the air conditioning case (10) for heating air;
A cold air bypass passage (21) for bypassing the heater core (20);
An air mix door (19) that adjusts the ratio between the amount of air that passes through the heater core (20) and is heated and becomes warm air, and the amount of cold air that passes through the cold air bypass passage (21);
An air mixing section (24) for mixing hot air and cold air adjusted by the air mix door (19);
A face opening (27) for guiding the mixed air that has passed through the air mixing section (24) to an occupant head chest in the passenger compartment;
A foot opening (29) for guiding the mixed air to the feet of passengers in the passenger compartment;
A blowing mode switching door (28) for adjusting the air volume passing through both openings (27, 29);
An auxiliary cold air bypass passage (17) that is arranged separately from the cold air bypass passage (21) and passes the cold air that bypasses the heater core (20) in the direction of the face opening (27);
In a vehicle air conditioner having a cold air bypass door (18) for adjusting the amount of cold air passing through the auxiliary cold air bypass passage (17),
In the blowing mode in which the face opening (27) is opened, the auxiliary cold air bypass passage (17) is opened, and in the blowing mode in which the face opening (27) is closed, the auxiliary cold air bypass passage (17) is closed.

  According to the first aspect of the present invention, since the auxiliary cold air bypass passage (17) is opened in the blowing mode in which the face opening (27) is opened, specifically, in the face blowing mode and the bi-level blowing mode, A large vertical temperature difference can be ensured as compared with the conventional case, and a relatively cool cold air can be obtained from the face air outlet even when the foot has a high air outlet temperature. Thus, even when there is solar radiation at a low outside temperature, it is possible to obtain a stable head-and-foot air conditioning feeling. In other words, the bi-level blowing mode can be used even in an area that could conventionally be used only in the foot blowing mode, and the use area of the bi-level blowing mode can be expanded.

  Further, in the invention according to claim 2, in the vehicle air conditioner according to claim 1, the cold air bypass door (18) can be opened and closed in conjunction with the blowing mode switching door (28). It is a feature.

  According to the second aspect of the present invention, the conventional cold air bypass door is opened and closed separately from the blow mode switching door, thereby affecting the balance of the air flow flowing through each part, and also in the air conditioning feeling of other parts that are not intended. The problem of influencing can be prevented by operating the cold air bypass door (18) and the blowing mode switching door (28) in conjunction with each other.

  Conventionally, a dedicated drive mechanism has been required to open and close the cold air bypass door separately. This makes it possible to control the opening degree of the cold air bypass door according to the values of various sensors, but the door opening / closing control becomes very complicated and the cost, space, and weight of the dedicated drive mechanism increase. There was also a problem.

  On the other hand, since the cold air bypass door (18) and the blowing mode switching door (28) are interlocked, a dedicated drive mechanism is not required, so that the opening / closing control of the door is not complicated. Cost, space, and weight can be reduced. Further, the operation of the cold air bypass door (18) is not stopped halfway, and is a simple operation that is opened when the face opening (27) is opened and closed when the face opening (27) is closed. Therefore, the interlocking mechanism can also have a simple configuration.

  Incidentally, in Patent Document 2 described above, the driving of the cold air bypass door is linked with the driving of the blowout mode switching door, but the cold air bypass door in this document is arranged downstream of the air mix door to establish temperature control. Therefore, it is not intended to expand the bi-level blowing mode area as in the present invention.

  According to a third aspect of the present invention, in the vehicle air conditioner according to the first or second aspect, the control means (5) is provided, and the blowout mode is automatically set according to the calculated target blowout temperature (TAO). In addition, when the foot blowing mode is selected in the judgment of the blowing mode based on the target blowing temperature (TAO), the bi-level blowing mode is selected when the detected solar radiation amount (Ts) is a predetermined value or more. It is characterized by that.

  According to the third aspect of the invention, as a method for determining the blowing mode, not only the conventional target blowing temperature (TAO) but also the amount of solar radiation (Ts) is combined, and when the amount of solar radiation (Ts) is a predetermined value or more, The bi-level blowing mode can be used even in an area that can be used only in the foot blowing mode in the past by selecting the head cold foot type bi-level blowing mode.

  According to a fourth aspect of the present invention, in the vehicle air conditioner according to the first or second aspect, the control means (5) is provided, and the blowing mode is automatically set according to the calculated target blowing temperature (TAO). In addition, when the foot blowing mode is selected in the judgment of the blowing mode based on the target blowing temperature (TAO), the bi-level blowing mode is selected when the detected inside air temperature (Tr) is equal to or higher than a predetermined value. It is characterized by that.

  According to the fourth aspect of the invention, as a method for determining the blowing mode, not only the conventional target blowing temperature (TAO) but also the inside air temperature (Tr) is combined, and when the inside air temperature (Tr) is a predetermined value or more, By selecting the cold level heat type bi-level blowing mode, it is possible to use the bi-level blowing mode even in an area that has been conventionally usable only in the foot blowing mode.

  According to a fifth aspect of the present invention, in the vehicle air conditioner according to the first or second aspect of the present invention, the control means (5) is provided, and the blowing mode is automatically set according to the calculated target blowing temperature (TAO). When the foot blow mode is selected in the blow mode determination based on the target blow temperature (TAO), the bi-level blow is performed when the detected internal air temperature (Tr) is higher than the set temperature (Tset) by a predetermined value or more. The feature is that the mode is selected.

  According to the fifth aspect of the present invention, as a method for determining the blowing mode, not only the conventional target blowing temperature (TAO) but also the difference between the inside air temperature (Tr) and the set temperature (Tset) is combined. When the inside air temperature (Tr) is higher than the set temperature (Tset) by a predetermined value or more, the bi-level blowing mode is used even in the area that was conventionally only available in the foot blowing mode by selecting the head-cold foot heat type bi-level blowing mode. Can be able to.

  In the present invention, in order to improve the comfort at the time of steady state, a transient state such as immediately after starting is not a target. Incidentally, the reference numerals in parentheses of the above means are examples showing the correspondence with the specific means described in the embodiments described later.

(First embodiment)
Hereinafter, a first embodiment of the present invention (corresponding to claims 1 and 2) will be described in detail with reference to FIGS. 1 to 5 are diagrams for explaining an automatic air conditioner system according to an embodiment of the present invention. FIG. 1 is a block diagram showing the overall configuration of an automatic air conditioner system, and FIG. 2 is a cross-sectional view of an air conditioning unit 15 of a vehicle air conditioner according to a first embodiment of the present invention.

  FIG. 3 is a block diagram showing a configuration of a control system in the automatic air conditioner system of FIG. 1, and FIG. 4 is a flowchart showing an overall control program in the air conditioner ECU 5 of FIGS. FIG. 5 is a characteristic diagram of the air conditioner ECU 5 in the flowchart of FIG. 4, where (a) shows the air outlet mode characteristics, (b) shows the inside / outside air mode characteristics, and (c) shows the blower control voltage characteristics. .

  The refrigeration cycle R of the vehicle air conditioner is provided with a compressor 1 that sucks, compresses and discharges the refrigerant. The compressor 1 is a variable capacity compressor 1 that varies the compression capacity by a variable capacity mechanism, and the compression capacity is controlled by a control valve 33 as a cooling capacity variable means. The control valve 33 is controlled by an air conditioner ECU 5 as control means of the air conditioner.

  The compressor 1 has an electromagnetic clutch 2 for power interruption, and the power of the vehicle travel engine 4 is transmitted to the compressor 1 via the electromagnetic clutch 2 and the V belt 3. The energization of the electromagnetic clutch 2 is interrupted by the air conditioner ECU 5, and when the electromagnetic clutch 2 is energized and connected, the compressor 1 is in an operating state. On the other hand, when the energization of the electromagnetic clutch 2 is cut off and the disengaged state is established, the compressor 1 stops.

  The high-temperature and high-pressure gas refrigerant discharged from the compressor 1 flows into the condenser 6, where the refrigerant is cooled and condensed by exchanging heat with outside air cooling air blown from a cooling fan (not shown). The refrigerant condensed in the condenser 6 then flows into the receiver 7, where the gas-liquid refrigerant is separated inside the receiver 7, and surplus refrigerant in the refrigeration cycle R is stored in the receiver 7 as liquid refrigerant.

  The liquid refrigerant from the receiver 7 is depressurized to a low pressure by a decompression means 8 such as an expansion valve, and enters a low-pressure gas-liquid two-phase state. The low-pressure refrigerant from the expansion valve 8 flows into an evaporator (cooling heat exchanger) 9 as air cooling means. The evaporator 9 is installed in an air conditioning case (air conditioning duct) 10 of a vehicle air conditioner, and the low-pressure refrigerant that has flowed into the evaporator 9 absorbs heat from the air flowing in the air conditioning case 10 and evaporates. The refrigerant outlet of the evaporator 9 is connected to the suction side of the compressor 1 and forms a closed circuit with the above-described cycle components.

  In the air conditioning case 10, a blower unit 11 as a blowing unit is disposed upstream of the evaporator 9, and the blower unit 11 is provided with a blower fan 12 and a blower motor 13. An inside / outside air switching box 14 as an inside / outside air switching means is arranged on the suction side of the blower fan 12, and an open / close ratio between the outside air introduction port 14b and the inside air introduction port 14c by the inside / outside air switching door 14a in the inside / outside air switching box 14 is provided. Is variable.

  Thereby, introduction switching or introduction ratio of outside air (vehicle compartment outside air) or inside air (vehicle compartment air) into the inside / outside air switching box 14 is adjusted. The inside / outside air switching door 14a is driven by a servo motor 14d as an electric drive device. The blower motor 13 and the servo motor 14d are controlled by the air conditioner ECU 5, respectively.

  Of the air conditioning system ventilation system, the air conditioning unit 15 disposed on the downstream side of the blower unit 11 is usually disposed at a substantially central position in the vehicle width direction inside the instrument panel in the front part of the vehicle interior, and the blower unit 11 is the air conditioning unit. 15 is offset from the passenger seat side. 1 is a general schematic diagram, and FIG. 2 is a cross-sectional view of the air conditioning unit 15 of the vehicle air conditioner according to the first embodiment of the present invention. Here, an outline of the structure of the air conditioning unit 15 will be described with reference to FIG.

  This air conditioning unit 15 is of a type in which both the previous evaporator 9 and the heater core (heat exchanger for air heating) 20 are integrally incorporated in one common air conditioning case 10. The air conditioning case 10 is a molded product of resin having a certain degree of elasticity and excellent strength, such as polypropylene.

  The air-conditioning case 10 is specifically composed of a plurality of divided cases. The plurality of divided cases are accommodated after storing the heat exchangers 9 and 20 and the doors 18, 19, 26, and 28 described later. The air conditioning unit 15 is integrally connected by fastening means such as a metal spring clip or a screw. The air conditioning unit 15 is arranged in the form shown in FIG. 2 with respect to the longitudinal direction and the vertical direction of the vehicle. An air inlet 16 is formed on the side surface of the air conditioning case 10 closest to the front side of the vehicle.

  Air-conditioned air blown from the previous blower unit 11 flows into the air inlet 16. And the evaporator 9 is arrange | positioned in the site | part just after the air inlet 16 in the air-conditioning case 10. FIG. The evaporator 9 has a thin shape in the vehicle front-rear direction and is arranged in the vertical direction so as to cross the passage in the air conditioning case 10. Therefore, the blown air from the air inlet 16 flows into the entire surface of the evaporator 9 extending in the vehicle vertical direction.

  And the heater core 20 is arrange | positioned at predetermined intervals on the air flow downstream side (vehicle rear side) of the evaporator 9. The heater core 20 is disposed on the lower side in the air conditioning case 10 so as to be inclined toward the vehicle rear side. Although not shown, the width dimension of the evaporator 9 and the heater core 20 in the left-right direction of the vehicle is designed to be substantially the same as the width dimension of the air conditioning case 10.

  The heater core 20 reheats the cold air that has passed through the evaporator 9, high temperature hot water (engine cooling water) flows through the heater core 20, and heats the air using this hot water as a heat source. In the air passage in the air conditioning case 10, a cold air bypass passage 21 that bypasses the heater core 20 and flows air (cold air) is formed above the heater core 20.

  Further, a flat air mix door 19 is disposed at a portion between the heater core 20 and the evaporator 9. The air mix door 19 adjusts the amount of air that passes through the heater core 20 and becomes hot air, and the amount of cold air that bypasses the heater core 20 through the cold air bypass passage 21. By adjusting the ratio, the temperature of the air blown into the passenger compartment is adjusted.

  The air mix door 19 is integrally coupled to a rotation shaft 19a disposed in the horizontal direction (vehicle width direction), and is rotatable in the vehicle vertical direction around the rotation shaft 19a. The rotating shaft 19a is rotatably supported by the air conditioning case 10, and one end portion of the rotating shaft protrudes outside the air conditioning case 10, and an actuator mechanism using a servo motor or the like via a link mechanism (not shown). 22 (see FIG. 1). The actuator mechanism 22 is controlled by the air conditioner ECU 5 to adjust the rotational position of the air mix door 19.

  On the other hand, in the air conditioning case 10, a wall surface 10 a that extends in the vertical direction with a predetermined interval from the heater core 20 is formed as a part of the air conditioning case 10 at a portion on the air downstream side (vehicle rear side) of the heater core 20. ing. The wall surface 10a forms a warm air passage 23 that extends upward immediately after the heater core 20 (on the air downstream side).

  The hot air passage 23 joins the downstream side of the cold air bypass passage 21 in the upper part of the heater core 20 to form an air mixing portion 24 that mixes the cold air and the hot air. And in the upper surface part of the air-conditioning case 10, the defroster opening part 25 into which the air-conditioning air temperature-controlled by the air mixing part 24 flows in the site | part near the vehicle front is opening. The defroster opening 25 is connected to a defroster outlet in the vehicle compartment via a defroster duct (not shown), and blows wind from the defroster outlet toward the inner surface of the vehicle front window glass.

  The defroster opening 25 is opened and closed by a flat-plate defroster door 26 that is one of the blowout mode switching doors. The defroster door 26 is rotated by a rotation shaft 26 a disposed in the horizontal direction in the vicinity of the upper surface portion of the air conditioning case 10. The defroster door 26 adjusts the opening ratio between the defroster opening 25 and the communication port 34. The communication port 34 is a passage for allowing the conditioned air from the air mixing unit 24 to flow to the next face opening 27 and foot opening 29 side.

  A face opening 27 is provided on the upper surface of the air-conditioning case 10 at a position on the vehicle rear side (close to the occupant) of the defroster opening 25. The face opening 27 is connected to the instrument panel via a face duct (not shown). It is connected to a face outlet that is disposed on the upper side, and wind is blown out from the face outlet toward the passenger's head and chest in the passenger compartment.

  Next, in the air conditioning case 10, a foot opening 29 is provided below the face opening 27. The foot opening 29 opens toward the left and right sides on the lower side of the air conditioning case 10, and foot ducts (not shown) are connected to the left and right sides. The other end of the foot duct is a foot air outlet toward the driver's and passenger's occupant feet, and the wind blows out from the foot air outlet to the driver's and passenger's occupant feet.

  Between the face opening 27 and the foot opening 29, a flat face foot switching door (blowing mode switching door) 28 is disposed so as to be rotatable by a rotary shaft 28a. The opening ratio between the portion 27 and the inlet 29a of the foot opening 29 is adjusted.

  Further, in the air passage in the air conditioning case 10, an auxiliary cold air bypass passage 17 is opened in parallel with the cold air bypass passage 21 in the upstream portion of the air mix door 19 on the downstream side of the air flow of the evaporator 9. A flat cold air bypass door 18 for opening and closing is disposed on the air upstream side of the auxiliary cold air bypass passage 17. The cold air from the auxiliary cold air bypass passage 17 mainly flows to the face opening 27.

  The cold air bypass door 18 is integrally coupled to a rotating shaft 18a arranged in the horizontal direction, and can be rotated in the vehicle front-rear direction together with the rotating shaft 18a. The cold air bypass door 18 constitutes temperature adjusting means for adjusting the temperature of air blown into the vehicle interior by opening and closing the auxiliary cold air bypass passage 17.

  As one of the features of the present invention, the defroster door 26, the face foot switching door 28, and the cold air bypass door 18 of the blowing mode switching door are connected to each other through a link mechanism whose rotational shafts 18a, 26a, and 28a are not shown. The link mechanisms are linked to each other, and the link mechanism is connected to the blower mode switching actuator mechanism 31 such as a servo motor (see FIG. 1). The actuator mechanism 31 is controlled by the air conditioner ECU 5 to adjust the rotation position of the link mechanism.

  Next, the outline | summary of the electric control part in this embodiment is demonstrated using FIG. 1 and FIG. 3 together. The vehicle is provided with an inside air temperature sensor 35a as an inside air temperature detecting means for detecting the vehicle interior air temperature Tr and an outside air temperature sensor 35b as an outside air temperature detecting means for detecting the vehicle outside air temperature Tam.

  Further, a post-evaporator sensor 32 as a cooling temperature detecting means for detecting a post-evaporator temperature Te as a cooling temperature is provided on the air blowing side of the evaporator 9 in the air conditioning case 10. In addition to the temperature sensors 32, 35a, and 35b described above, the air conditioner ECU 5 includes a known solar sensor 35c that detects the amount of solar radiation Ts for air conditioning control, a cooling water temperature sensor 35d that detects the cooling water temperature Tw, and the like. A detection signal is input from the sensor group 35 serving as an environmental condition detection unit, and a target blowing temperature TAO and the like to be described later are calculated.

  The air conditioner operation panel 36 installed in the vicinity of the vehicle interior instrument panel is provided with an operation switch group 37 that is manually operated by a passenger. An operation signal of the operation switch group 37 is also input to the air conditioner ECU 5, and the panel switch Input processing and display processing on the air conditioner operation panel 36 are performed.

  The operation switch group 37 includes a temperature setting switch 37a as a vehicle interior temperature setting means for generating a temperature setting signal Tset, an air volume switch 37b for generating an air volume switching signal, a blow mode switch 37c for generating a blow mode signal, and inside and outside air. An inside / outside air changeover switch 37d that generates a switching signal, an air conditioner switch 37e that generates an on / off signal for the compressor 1, and the like are provided. Note that the blowing mode switch 37c is used to manually switch between a well-known blowing mode, that is, a face mode, a bi-level mode, a foot mode, a foot defroster mode, and a defroster mode.

  The air conditioner ECU 5 includes a well-known microcomputer including a CPU, a ROM, a RAM, and the like, and peripheral circuits thereof. The air conditioner ECU 5 calculates a target post-evaporator temperature TEO as a target temperature, which will be described later, and a control unit that controls the control valve 33, and a suction port switching motor 14d that calculates the suction mode position and drives the inside / outside air switching door 14a. A control unit for controlling, a control unit for calculating the blown air volume to control the blower motor 13, a control unit for controlling the air mix motor 22 for driving the air mix door 19 as blowout temperature control, and calculating the blowout mode position A control unit for controlling the outlet switching motor 31 is provided.

  Next, the operation of this embodiment will be described with reference to the flowchart of FIG. 4 based on the processing procedure of the air conditioner ECU 5 when an auto switch (not shown) is turned on, that is, during auto control. First, when the ignition switch is turned on and power is supplied to the air conditioner ECU 5, the main routine shown in FIG. 4 is started. In step S1, the stored contents of the data processing memory (RAM) are initialized.

  Then, in the next step S2, the inside air temperature Tr detected by the inside air temperature sensor 35a, the outside air temperature Tam detected by the outside air temperature sensor 35b, the solar radiation amount Ts detected by the solar radiation sensor 35c, and the post-evaporator detected by the post-evaporator sensor 32. While inputting environmental conditions such as the temperature Te, the water temperature Tw detected by the water temperature sensor 35d, the actual opening TP of the air mix door 19 detected by the potentiometer in the servo motor 22, among the output signals from the operation panel 36, The state of the operation switch of the target temperature Tset set by the temperature setting switch 37a is input.

  Then, in the next step S3 which is the target blowing temperature calculation means, by substituting the Tset, Tr, Tam and Ts read in the above step S2 into the mathematical formula (omitted) stored in advance in the ROM, A target blowing temperature TAO of the conditioned air blown into the passenger compartment is calculated. In the next step S4, the blower air volume is calculated based on the target blowout temperature TAO into the vehicle interior obtained in step S3.

  In this embodiment, it has a calculation means which calculates | requires the blower control voltage VF corresponding to the target blowing temperature TAO from the ventilation characteristic of FIG.5 (c) which is the ventilation characteristic memory | storage means previously memorize | stored in ROM. In the next step S5, each blowing mode into the vehicle interior is determined based on the target blowing temperature TAO into the vehicle interior obtained in step S3 and the blowing mode characteristic diagram of FIG. 5 (a) stored in advance in the ROM. decide.

  Specifically, the target blowing temperature TAO is set to be in a face blowing mode, a high level (B / L) blowing mode, and a foot blowing mode from a low temperature to a high temperature. In the present invention, one of the features is that the application range of the high-level blowing mode is expanded by shifting the switching between the high-level blowing mode and the foot blowing mode to a higher temperature than the conventional one.

  Further, by operating a blow mode switching switch 37c provided on the operation panel 36, any one of a face blow mode, a high level blow mode, a foot blow mode or a foot defroster (F / D) blow mode is selected. Fixed to. The face blowing mode is a blowing mode in which air-conditioned air is blown toward the passenger's head and chest. Further, the bi-level blowing mode is a blowing mode in which air-conditioned air is blown toward the occupant's head and chest and feet.

  And foot blowing mode is blowing mode which blows off air-conditioning wind toward a crew member's step. Furthermore, the foot defroster blowing mode is a blowing mode in which air-conditioned air is blown toward the feet of the occupant and the inner surface of the front window glass of the vehicle. When a front defroster switch (not shown) provided on the operation panel 36 is operated, a defroster (DEF) blowing mode for blowing conditioned air toward the inner surface of the front window glass of the vehicle is set.

  In the next step S6, the target opening degree of the air mix door 19 is substituted by substituting the Tw, Te, and the TAO read in the step S2 into the mathematical formula (omitted) stored in the ROM in advance. SW is calculated. Then, in the next step S7, the introduction ratio of the inside / outside air is determined based on the target blowing temperature TAO obtained in the above step S3 and the inside / outside air mode characteristic diagram of FIG. 5B stored in the ROM in advance. . According to the inside / outside air mode characteristic diagram, the inside air mode is selected during the cooling operation (that is, when the TAO value is low).

  In the next step S8, a target post-evaporator temperature TEO for obtaining the target outlet temperature TAO determined in step S3 is calculated, and the target post-evaporator temperature TEO and the actual post-evaporator temperature Te that are detected values of the post-evaporator sensor 32 are calculated. Is determined by feedback control (PI control) so that the target discharge amount (target rotation speed) of the compressor 1 is determined.

  In the next step S9, a control signal for outputting the control amount of the blower voltage VF calculated in step S4 to a blower motor drive circuit (not shown) is output. As a result, the blower fan 12 fixed to the blower motor 13 is rotated to control the amount of blown air blown into the passenger compartment. Then, in the next step S10, a control signal is output to the outlet switching motor 31 based on the control amount that is the blowing mode determined in step S5.

  In the next step S11, a control signal is output to the air mix motor 22 based on the control amount that becomes the target opening degree SW of the air mix door 19 calculated in step S6. Then, in the next step S12, a control signal is output to the inlet motor 14d based on the control amount that is the introduction ratio of the inside / outside air determined in step S7. In the next step S13, the control current determined in step S8 is output to the control valve 33 connected to the compressor 1.

  After the process of step S13, the process returns to step S2 to read various signals again, whereby TAO is calculated in step S3, and steps S3 to S13 are performed depending on the state of these TAO and various input signals read in step S2. Thus, the control of the air conditioning to the vehicle interior is repeated. Note that each set value follows the set value when manually set.

  Next, the detail of the setting of the blowing mode which is the principal part of this invention is demonstrated using FIG. 6 and FIG. FIG. 6 is a door diagram showing changes in the opening degree of the defroster door 26 / face foot switching door 28 and the cold air bypass door 18 in the air conditioning unit 15 of FIG. The vehicle air conditioner of the present embodiment sets the following blow modes by selecting the operation positions of the defroster door 26 and the face foot switch door 28 of the blow mode switching door.

(1) Face blowing mode As shown in the door diagram of FIG. 2, the defroster door 26 has the defroster opening 25 at 0% opening (fully closed) and the communication port 34 at 100% opening (fully open). Further, the face foot switching door 28 has a face opening 27 with a 100% opening (fully open) and a foot inlet 29a with a 0% opening (fully closed). The cold air bypass door 18 has a 100% opening (fully open). The air mix door 19 sets the maximum cooling state with the cold air bypass passage 21 fully opened.

  In this state, when the blower unit 11 and the refrigeration cycle R are operated, the blown air from the blower unit 11 flows from the air inlet 16 and is then cooled by the evaporator 9 to become cold air. In the maximum cooling state, the cold air remains as it is, passes through both the cold air bypass passage 21 and the auxiliary cold air bypass passage 17, passes through the air mixing unit 24, travels to the face opening 27, and faces the occupant's head and chest from the face outlet. Cold wind blows out.

(2) Bilevel blowing mode The defroster door 26 has the defroster opening 25 at 0% opening (fully closed) and the communication port 34 at 100% opening (fully open). Further, the face foot switching door 28 has a substantially intermediate opening. The cold air bypass door 18 has a 100% opening (fully open). Since the bi-level blowing mode is usually used frequently in the middle season of spring and autumn, the air mix door 19 is operated to an intermediate opening position, and the wind adjusted to a desired temperature is applied to the face opening 27 and the foot opening 29. Blow out from both up and down in the passenger compartment at the same time.

(3) Foot blowing mode The defroster door 26 has a defroster opening 25 with an opening of approximately 20% and a communication port 34 with an opening of approximately 80%. Further, the face foot switching door 28 has a face opening 27 having a 0% opening (fully closed) and a foot inlet 29a having a 100% opening (fully opening). The cold air bypass door 18 has a 0% opening (fully closed). In this state, the air mix door 19 fully opens the warm air passage 23 side passing through the heater core 20.

  As a result, after the entire amount of the blown air from the blower unit 11 is heated by the heater core 20, most of the hot air is blown from the foot opening 29 through the foot outlet toward the occupant's feet. Heating is done. Further, a small amount of warm air is blown out from the defroster outlet through the defroster opening 25 toward the inside of the vehicle front window glass, thereby preventing the front window glass from being fogged.

(4) Foot defroster blowing mode The defroster door 26 has the defroster opening 25 at a substantially intermediate opening, and the communication port 34 also has a substantially intermediate opening. Further, the face foot switching door 28 has a face opening 27 having a 0% opening (fully closed) and a foot inlet 29a having a 100% opening (fully opening). The cold air bypass door 18 has a 0% opening (fully closed). In this state, the air mix door 19 fully opens the warm air passage 23 side passing through the heater core 20.

  As a result, after the entire amount of the blown air from the blower unit 11 is heated by the heater core 20, approximately half of the warm air is blown out from the defroster opening 25 toward the inside of the vehicle front window glass through the defroster opening 25. The hot air blows out approximately half of the warm air from the foot opening 29 through the foot outlet and toward the feet of the occupant to heat the passenger compartment.

(5) Defroster blowing mode The defroster door 26 has the defroster opening 25 at 100% opening (fully open), and the communication port 34 has 0% opening (fully closed). Further, the face foot switching door 28 has a face opening 27 having a 0% opening (fully closed) and a foot inlet 29a having a 100% opening (fully opening). The cold air bypass door 18 has a 0% opening (fully closed). In this state, the air mix door 19 fully opens the warm air passage 23 side passing through the heater core 20.

  Thus, after the entire amount of the air blown from the blower unit 11 is heated by the heater core 20, the warm air blows out from the defroster opening through the defroster opening 25 toward the inside of the vehicle front window glass, and the front window glass is cloudy. Stop is done.

  When the air mix door 19 is operated from the maximum cooling position to the intermediate opening position in order to control the temperature of the air blown into the passenger compartment, most of the cold air passes through the cold air bypass passage 21 according to the opening position of the air mix door 19. The remaining part of the cool air flows into the heater core 20 and is heated to become warm air and flows into the warm air passage 23. And this warm air and the cold wind of the cold wind bypass passage 21 are mixed in the air mixing part 24, and are adjusted to desired temperature.

  Next, features and effects of this embodiment will be described. First, the auxiliary cold air bypass passage 17 is opened in the blowing mode in which the face opening 27 is opened, and the auxiliary cold air bypass passage 1) is closed in the blowing mode in which the face opening 27 is closed. According to this, since the auxiliary cold air bypass passage 17 is opened in the blowing mode in which the face opening 27 is opened, specifically, in the face blowing mode and the bi-level blowing mode, a large vertical temperature difference is ensured compared to the conventional case. It is possible to obtain a relatively cool cold air from the face air outlet even when the foot is at a high temperature.

  FIG. 7 is a graph showing the relationship between the air mix door opening SW and the temperature of air blown from each outlet. By lowering the blowing temperature from the face blowing outlet in the bi-level blowing mode than before, the bi-level blowing mode can be used even in an area that has been conventionally usable only in the foot blowing mode.

  That is, even when the foot side has a high blowing temperature, the face side can be kept below the high temperature limit (for example, 30 ° C.) of the blowing temperature, so that the use area of the bi-level blowing mode can be expanded to the high temperature side. Thereby, even when there is solar radiation at a low outside temperature, it is possible to obtain a stable air-conditioning feeling of head cold foot heat. Incidentally, the blowing mode for closing the face opening 27 is specifically the above-described foot blowing mode, foot defroster blowing mode, defroster blowing mode, or the like.

  In addition, the cold air bypass door 18 can be opened and closed in conjunction with the defroster door 26 and the face foot switching door 28 of the blowing mode switching door. According to this, by opening and closing the conventional cold air bypass door separately from the blow mode switching door, it affects the air volume balance flowing through each part and affects the air conditioning feeling of other parts that are not intended. On the other hand, it can prevent by operating the cold wind bypass door 18 and the blowing mode switching doors 26 and 28 in conjunction.

  Conventionally, a dedicated drive mechanism has been required to open and close the cold air bypass door separately. This makes it possible to control the opening degree of the cold air bypass door according to the values of various sensors, but the door opening / closing control becomes very complicated and the cost, space, and weight of the dedicated drive mechanism increase. There was also a problem.

  On the other hand, by linking the cold air bypass door 18 and the blow-out mode switching doors 26 and 28, a dedicated drive mechanism becomes unnecessary, and the opening / closing control of the door is not complicated, and the cost of the interlock mechanism is reduced. Space and weight increase can be suppressed. Further, the operation of the cold air bypass door 18 is not stopped halfway, and is simply opened when the face opening 27 is opened and closed when the face opening 27 is closed. It can be set as a simple structure.

(Second Embodiment)
FIG. 8 is a partial flowchart of the outlet determination in the second embodiment (corresponding to claim 3) of the present invention. In the blowing mode determination in step S5 in the flowchart of FIG. 4, the solar radiation amount Ts detected by the solar radiation sensor 35c is used. First, in step S21, the blowing mode to be set is determined according to the target blowing temperature TAO as described above.

  If the determination result in step S21 is a face, the process proceeds to step S22 to set the face blowing mode, and if the determination result in step S21 is the bilevel, the process proceeds to step S23 to set the bilevel blowing mode. However, if the determination result in step S21 is foot, the process first proceeds to step S24 to determine whether or not the solar radiation amount Ts is equal to or greater than a predetermined value.

  If the determination result in step S24 is YES and the solar radiation amount Ts is greater than or equal to a predetermined value, the process proceeds to step S23 to set the bi-level blowing mode, the determination result in step S24 is NO, and the solar radiation amount Ts is a predetermined value. When it is below, it progresses to step S25 and sets it as the foot blowing mode.

  Next, features and effects different from those of the first embodiment will be described. In the present embodiment, the air conditioner ECU 5 is provided, and the blowing mode is automatically switched according to the calculated target blowing temperature TAO, and is detected when the foot blowing mode is selected in the blowing mode determination based on the target blowing temperature TAO. When the solar radiation amount Ts is equal to or greater than a predetermined value, the bi-level blowing mode is selected.

  According to this, as a method for determining the blowing mode, not only the conventional target blowing temperature TAO but also the solar radiation amount Ts, and when the solar radiation amount Ts is a predetermined value or more, the head cold foot heat type bi-level blowing mode is selected. The bi-level blowing mode can be used even in an area that can be used only in the foot blowing mode.

(Third embodiment)
FIG. 9 is a partial flowchart of determining the air outlet in the third embodiment (corresponding to claim 4) of the present invention. In the blowing mode determination in step S5 in the flowchart of FIG. 4, the inside air temperature Tr detected by the inside air temperature sensor 35a is used. The above-described flowchart shown in FIG. 8 and the flowchart according to the present embodiment shown in FIG. The only difference is that it has been changed to “no”.

  If the determination result in step S241 is YES and the inside air temperature Tr is greater than or equal to a predetermined value, the process proceeds to step S23 to set the bi-level blowing mode, the determination result in step S241 is NO, and the inside air temperature Tr is a predetermined value. When it is below, it progresses to step S25 and sets it as the foot blowing mode.

  Next, features and effects different from those of the above-described second embodiment will be described. In the present embodiment, the air conditioner ECU 5 is provided, and the blowing mode is automatically switched according to the calculated target blowing temperature TAO, and is detected when the foot blowing mode is selected in the blowing mode determination based on the target blowing temperature TAO. When the inside air temperature Tr is equal to or higher than a predetermined value, the bi-level blowing mode is selected.

  According to this, as a method for determining the blowing mode, not only the conventional target blowing temperature TAO but also the inside air temperature Tr is combined, and when the inside air temperature Tr is equal to or higher than a predetermined value, the head cold foot heat type bi-level blowing mode is selected. It is possible to make it possible to use the bi-level blowing mode even in an area that has been conventionally usable only in the foot blowing mode.

(Fourth embodiment)
FIG. 10 is a partial flowchart of the outlet determination in the fourth embodiment (corresponding to claim 5) of the present invention. In the blowing mode determination in step S5 in the flowchart of FIG. 4, the inside air temperature Tr detected by the inside air temperature sensor 35a and the target temperature Tset set by the temperature setting switch 37a are used. The above-described flowchart shown in FIG. 8 and the flowchart according to the present embodiment shown in FIG. 10 include a determination part of step S24 “whether or not the solar radiation amount is not less than a predetermined value” as “step S2421” Only the change to the determination of “whether or not the value is greater than or equal to” is different.

  If the determination result in step S242 is YES and the inside air temperature-set temperature is equal to or higher than the predetermined value, the process proceeds to step S23 to set the bi-level blowing mode, the determination result in step S242 is NO, and the inside air temperature-setting When the temperature is equal to or lower than the predetermined value, the process proceeds to step S25 to set the foot blowing mode.

  Next, features and effects different from those of the second and third embodiments described above will be described. In the present embodiment, the air conditioner ECU 5 is provided, and the blowing mode is automatically switched according to the calculated target blowing temperature TAO, and is detected when the foot blowing mode is selected in the blowing mode determination based on the target blowing temperature TAO. When the inside air temperature Tr is equal to or higher than a predetermined value higher than the set temperature Tset, the bi-level blowing mode is selected.

  According to this, as a method for determining the blowing mode, not only the conventional target blowing temperature TAO but also the difference between the inside air temperature Tr and the set temperature Tset is combined, and the inside air temperature Tr is higher than the set temperature Tset by a predetermined value or more by the difference. Sometimes, the bi-level blowing mode can be used even in an area that has been conventionally used only in the foot blowing mode by selecting the birch blowing mode of the head cold foot type.

(Other embodiments)
The present invention is not limited to the above-described embodiment. In the above-described embodiment, the ventilation surfaces of both heat exchangers (evaporator / heater core) are vertically arranged so as to be continuous in the front-rear direction of the vehicle. However, it may be arranged such that the ventilation surfaces of both heat exchangers stand vertically and are continuous in the left-right direction of the vehicle, or the ventilation surfaces of both heat exchangers lie sideways in the vertical direction of the vehicle. It may be arranged in a row.

  In the embodiment of FIG. 5, the blowout mode switching door has a two-sheet configuration including the defroster door 26 and the face foot door 28, but has a two-sheet configuration including a defroster foot door and a face door. Alternatively, as shown in the schematic diagram of FIG. 1, it may be a three-sheet configuration including a defroster door, a face door, and a foot door, or one surface sliding door such as a film door or a rotary door. It may have a configuration summarized in

It is the schematic diagram which showed the whole structure of the automatic air-conditioning system concerning embodiment of this invention. It is sectional drawing of the air conditioning unit 15 of the vehicle air conditioner in 1st Embodiment of this invention. It is a block diagram which shows the structure of the control system in the automatic air-conditioning system of FIG. It is a flowchart which shows the whole control program in the air-conditioner ECU5 of FIG. FIG. 5 is a characteristic diagram of the air conditioner ECU 5 in the flowchart of FIG. 4, where (a) shows an outlet mode characteristic, (b) shows an inside / outside air mode characteristic, and (c) shows a blower control voltage characteristic. It is a door diagram which shows transition of the opening degree of the defroster door 26, the face foot switching door 28, and the cold wind bypass door 18 in the air conditioning unit 15 of FIG. It is a graph which shows the relationship between air mix door opening degree SW and the blowing temperature from each blower outlet. It is a partial flowchart of the blower outlet determination in 2nd Embodiment of this invention. It is a partial flowchart of the blower outlet determination in 3rd Embodiment of this invention. It is a partial flowchart of the blower outlet determination in 4th Embodiment of this invention.

Explanation of symbols

5. Air conditioner ECU (control means)
DESCRIPTION OF SYMBOLS 10 ... Air-conditioning case 17 ... Auxiliary cold wind bypass passage 18 ... Cold wind bypass door 19 ... Air mix door 20 ... Heater core 21 ... Cold wind bypass passage 24 ... Air mixing part 27 ... Face opening 28 ... Face foot switching door (blow-out mode switching door)
29 ... Foot opening TAO ... Target blowing temperature Tr ... Inside air temperature Ts ... Solar radiation amount Tset ... Setting temperature

Claims (5)

An air conditioning case (10) forming an air passage;
A heater core (20) disposed in the air conditioning case (10) for heating air;
A cold air bypass passage (21) for bypassing the heater core (20);
An air mix door (19) that adjusts the ratio of the amount of air that passes through the heater core (20) and is heated and becomes warm air, and the amount of cold air that passes through the cold air bypass passage (21);
An air mixing section (24) for mixing the warm air and the cool air adjusted by the air mix door (19);
A face opening (27) for guiding the mixed air that has passed through the air mixing section (24) to an occupant head chest in the passenger compartment;
A foot opening (29) for guiding the mixed air to a passenger's feet in the passenger compartment;
A blow mode switching door (28) for adjusting the air volume passing through the openings (27, 29);
An auxiliary cold air bypass passage (17) arranged separately from the cold air bypass passage (21) and passing the cold air bypassing the heater core (20) in the direction of the face opening (27);
A vehicle air conditioner having a cold air bypass door (18) for adjusting the amount of cold air passing through the auxiliary cold air bypass passage (17);
The auxiliary cold air bypass passage (17) is opened during the blowing mode in which the face opening (27) is opened, and the auxiliary cold air bypass passage (17) is closed in the blowing mode in which the face opening (27) is closed. A vehicle air conditioner.   The vehicle air conditioner according to claim 1, wherein the cold air bypass door (18) can be opened and closed in conjunction with the blowing mode switching door (28).   In the case where the control unit (5) is provided and the blowing mode is automatically switched according to the calculated target blowing temperature (TAO), and the foot blowing mode is selected in the blowing mode determination based on the target blowing temperature (TAO), The vehicle air conditioner according to claim 1 or 2, wherein the bi-level blowing mode is selected when the detected amount of solar radiation (Ts) is a predetermined value or more.   In the case where the control unit (5) is provided and the blowing mode is automatically switched according to the calculated target blowing temperature (TAO), and the foot blowing mode is selected in the blowing mode determination based on the target blowing temperature (TAO), The vehicle air conditioner according to claim 1 or 2, wherein the bi-level blowing mode is selected when the detected inside air temperature (Tr) is equal to or higher than a predetermined value.   In the case where the control unit (5) is provided and the blowing mode is automatically switched according to the calculated target blowing temperature (TAO), and the foot blowing mode is selected in the blowing mode determination based on the target blowing temperature (TAO), The vehicle air conditioner according to claim 1 or 2, wherein the bi-level blowing mode is selected when the detected inside air temperature (Tr) is higher than a set temperature (Tset) by a predetermined value or more. .

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