JP2013154749A - Vehicle air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the following problem of a conventional device formed by combining "reheating type temperature control" and "air mixing type temperature control": when an A/M door is set at an intermediate position in a B/L mode so that the volume of air passing through an indoor condenser is reduced for increasing pressure in the indoor condenser to form a predetermined high-low temperature difference, while securing the required amount of heat release from the indoor condenser, power of a motor driven compressor is increased.SOLUTION: In a B/L mode, an A/M door 28 is fully opened for adjusting a degree of supercooling (SC) of outlet refrigerant in an indoor condenser 4 depending on the throttle openings of two first and second throttles 11, 12 to generate temperature distribution on the air downstream side of the indoor condenser 4 to have a low temperature region and a high temperature region. A predetermined high-low temperature difference (10°C, e.g.) is generated between a FACE outlet and a FOOT outlet while securing the required amount of heat released from the indoor condenser 4, without further increasing pressure in the indoor condenser 4 than conventional one, thus suppressing an increase in power consumption of a motor driven compressor 3.

Description

  The present invention relates to a vehicle air conditioner, and more particularly to a heat pump type air conditioner that heats the interior of an electric vehicle or a hybrid vehicle.

[Conventional technology]
Conventionally, in a vehicle air conditioner such as an electric vehicle, for example, a compressor that compresses and discharges a refrigerant, a condenser that condenses gaseous refrigerant (refrigerant gas) discharged from the compressor, and this condenser There are decompression means for decompressing and expanding the liquid refrigerant (liquid refrigerant) that has flowed out, an evaporator for evaporating the gas-liquid two-phase refrigerant that has flowed out of the decompression means, and a pipe that sequentially connects these in an annular manner, and the refrigerant circulates It has a refrigeration cycle.
And in the vehicle air conditioner provided with the refrigeration cycle as described above, the evaporator of the refrigeration cycle is arranged as a heat exchanger for cooling to cool the air in the air conditioning duct through which the air blown by the indoor blower flows. A heat pump air conditioner in which a condenser of a refrigeration cycle is arranged instead of a hot water heater is known as a heating heat exchanger that reheats air (cold air) that has passed through the vessel.

Outside the air conditioning duct, it functions as a condenser or evaporator during cooling operation for cooling the vehicle interior, functions as evaporator during heating operation for heating the vehicle interior, and condenser or evaporation during heating operation for dehumidifying and heating the vehicle interior. An outdoor heat exchanger that functions as a heat exchanger is installed.
And in the downstream of an air-conditioning duct, the several blower outlet for blowing off air-conditioned wind in a vehicle interior is provided. The plurality of air outlets include an upper air outlet (for example, a defroster air outlet and a face air outlet) for blowing conditioned air upward in the vertical direction of the vehicle interior, and an air conditioner on the lower side in the vertical direction of the vehicle interior. A lower air outlet (for example, a foot air outlet) for blowing wind is common.

By the way, there are two types of temperature control methods for air blown out from a plurality of outlets: “reheat type temperature control” and “air mix type temperature control”.
“Reheat-type temperature control” is a method of adjusting the temperature of the indoor heat exchanger.
In addition, the “air mix type temperature control” is an air volume ratio between the amount of air passing through the indoor heat exchanger and the amount of bypass air flowing through the bypass flow path bypassing the indoor heat exchanger by adjusting the air mix door opening. It is a method to adjust.
In a heat pump type air conditioner having an indoor condenser as an indoor heat exchanger in the air conditioning duct, the rotational speed of the electric motor driven compressor is changed to adjust the discharge capacity of the refrigerant discharged from the compressor Thus, “reheat-type temperature control” for controlling the temperature of the indoor condenser is applied.

However, as in “air mix type temperature control”, a face outlet for blowing air-conditioned air toward the upper body of the vehicle occupant or a defroster outlet for blowing air-conditioned air toward the inner surface of the window glass of the vehicle Control cannot be performed while creating a predetermined vertical temperature difference (for example, 10 to 15 degrees) between the blowing temperature and the blowing temperature at the foot outlet for blowing the conditioned air toward the feet of the vehicle occupant.
Therefore, a vehicle air conditioner has been proposed in which “reheat-type temperature control” and “air mix-type temperature control” are combined to control the temperature of air blown into the vehicle interior (for example, Patent Document 1). reference).
As shown in FIG. 15, this vehicle air conditioner (conventional device) includes an air conditioning duct 103 having a FACE opening 101 communicating with a FACE outlet and a FOOT opening 102 communicating with a FOOT outlet, and an electric compressor And a heat pump refrigeration cycle in which the refrigerant discharged from 104 circulates in the refrigerant circuit.

In the heat pump refrigeration cycle, the electric compressor 104, the indoor condenser 105, the first pressure reducing means 106, the outdoor heat exchanger 107, the second pressure reducing means 108, the indoor evaporator 109, the gas-liquid separator 110 and these are connected in a ring shape. It has refrigerant piping to do.
On the air upstream side of the indoor condenser 105, the air temperature ratio of the air quantity passing through the indoor condenser 105 and the air quantity bypassing the indoor condenser 105 is adjusted to adjust the temperature of air blown out into the vehicle interior. An air mix (A / M) door 111 is rotatably mounted.
The conventional apparatus is disposed upstream of the indoor condenser 105 by setting the A / M door 111 to an intermediate position in addition to the “reheat-type temperature control” during the dehumidifying heating operation and in the bi-level mode. Thus, a part of the air that has passed through the indoor evaporator 109 is diverted (bypassed) from the indoor condenser 105 to create a predetermined upper and lower temperature difference (for example, 10 to 15 degrees).

The operating state in the air-conditioning duct of the conventional apparatus at this time is shown in FIG. 15 (a), and the Mollier diagram of the refrigeration cycle is shown in FIG. 15 (b).
In the conventional apparatus, since the A / M door 111 is set at an intermediate position, when the temperature of the air that has passed through the indoor evaporator 109 is 0 ° C., the temperature of the air that has passed through the indoor condenser 105 is 75 ° C. The temperature of the air that has passed through the bypass passage 112 that bypasses the condenser 105 is 0 ° C.
The temperature of the air blown out from the FACE outlet communicating with the FACE opening 101 into the vehicle compartment is 30 ° C., and the temperature of the air blown out from the FOOT outlet connected to the FOOT opening 102 into the vehicle compartment is 40 ° C. That is, the upper and lower temperature difference is 10 degrees.
Note that the physical quantity is such that the temperature of the air passing through the inlet of the indoor condenser 105 is 96 ° C., the temperature of the air introduced into the indoor condenser 105 is 0 ° C., and the flow rate of air supplied to the indoor evaporator 109 is 150 m ^3. / H, the flow rate of air supplied to the indoor condenser 105 is 75 m ³ / h, and the flow rate of air passing through the bypass passage 112 is 75 m ³ / h.

[Conventional technical problems]
However, in the conventional apparatus, in addition to the “reheat type temperature control”, the “air mix type temperature control” is applied, and the A / M door 111 is set at an intermediate position to reduce the amount of air passing through the indoor condenser 105. Yes. In this case, if the temperature of the indoor condenser remains constant, the amount of heat released from the refrigerant to the air is reduced by the amount of air passing through the indoor condenser. It is necessary to increase the temperature of the indoor condenser 105, that is, the high-pressure pressure of the refrigeration cycle, by an amount corresponding to the decrease in the passing air volume of the condenser 105.
As a result, the pressure in the indoor condenser 105 is increased to ensure a necessary heat radiation amount, and a predetermined vertical temperature difference is created between the FACE outlet and the FOOT outlet.
As a result, the power consumption (compressor power) of the electric motor that drives the electric compressor 104 increases by an amount corresponding to the increase in the pressure of the indoor condenser 105. The problem of being invited arises.

Japanese Patent No. 3319168

  An object of the present invention is to provide a vehicle air conditioner capable of creating a predetermined temperature difference between a plurality of outlets while ensuring a necessary heat radiation amount in an indoor condenser while minimizing an increase in power of a compressor. To provide an apparatus.

According to the first aspect of the present invention (vehicle air conditioner), the air is blown into the vehicle compartment from the plurality of air outlets, as compared with the first air blowing mode in which the temperature difference of the air blown into the vehicle compartment from the air outlets is reduced. In the second blowing mode in which the temperature difference of the air is increased, the temperature distribution of the air that has passed through the indoor condenser (for example, a high temperature) is provided by having the throttle opening degree control means for reducing the throttle opening degree of the variable throttle means. Temperature distribution in which the temperature gradually decreases from the region to the low temperature region). Thereby, since the degree of supercooling of the outlet refrigerant of the indoor condenser can be increased in the second blowing mode than in the first blowing mode, the amount of air that has passed through the superheat region on the refrigerant outlet side of the indoor condenser is increased. Without raising the temperature, the temperature of the air that has passed through the subcooling region on the refrigerant outlet side of the indoor condenser is further lowered.
Thus, the temperature of the air that passes through the superheat region on the refrigerant inlet side of the indoor condenser and blows out from the first outlet to the vehicle interior, and passes through the subcool region on the refrigerant outlet side of the indoor condenser and passes through the second outlet. The temperature difference from the temperature of the air blown into the vehicle interior from the vehicle increases.
Therefore, the required pressure radiation from the refrigerant to the air in the indoor condenser is ensured between the first and second outlets without increasing the high pressure of the refrigeration cycle, that is, the pressure of the indoor condenser compared to the conventional apparatus. Therefore, the increase in compressor power can be minimized.

According to the third aspect of the present invention, the temperature of the indoor evaporator (by controlling the discharge capacity of the refrigerant discharged from the compressor based on the target temperature (TEO) of the indoor evaporator during the dehumidifying heating operation). TE) is controlled to be the target temperature (TEO) of the indoor evaporator.
According to the fourth aspect of the present invention, during the heating operation or the dehumidifying heating operation, the indoor condensation is controlled by controlling the discharge capacity of the refrigerant discharged from the compressor based on the target temperature (TAO) of the indoor condenser. The temperature (TAV) of the condenser is controlled to become the target temperature (TAO) of the indoor condenser.
In addition, you may make it control the discharge capacity of the refrigerant | coolant discharged from a compressor by adjusting the rotational speed of the electric motor which drives a compressor.

According to the eighth aspect of the present invention, the first and second variable throttle means are opened so that the detected value (TAV) of the condenser temperature detecting means becomes the calculated value (TAO) of the target condenser temperature calculating means. The degree ratio is determined.
According to the ninth aspect of the present invention, the throttle opening degree of the variable throttle means is adjusted so that the calculated value (current SC) of the supercooling degree calculating means becomes the calculated value (target SC) of the target supercooling degree calculating means. By doing so, in the second blowing mode in which the temperature difference of the air blown out from the plurality of outlets into the vehicle compartment is made larger than in the first blowing mode in which the temperature difference of the air blown out from the plurality of outlets into the vehicle compartment is reduced. The aperture of the variable throttle means becomes smaller.

  According to the invention described in claim 13, the throttle opening degree of the third variable throttle means is adjusted so that the calculated value (current SH) of the superheat degree calculating means becomes the calculated value (target SH) of the target superheat degree calculating means. By doing so, in the second blowing mode in which the temperature difference of the air blown out from the plurality of outlets into the vehicle compartment is made larger than in the first blowing mode in which the temperature difference of the air blown out from the plurality of outlets into the vehicle compartment is reduced. The throttle opening of the third variable throttle means becomes small.

It is a block diagram which showed the vehicle air conditioner (Example 1). (A) is explanatory drawing which showed the operation state in an air-conditioning duct, (b) is the Mollier diagram of a refrigerating cycle (Example 1). It is the flowchart which showed the basic control processing by air-conditioning ECU (Example 1). 6 is a flowchart illustrating operation mode determination control by the air conditioning ECU (Example 1). It is the flowchart which showed the blowing temperature control by air-conditioning ECU (Example 1). (A) is the characteristic figure which showed the relationship between the opening degree of a 1st, 2nd aperture | diaphragm, and an opening degree pattern (opening ratio), (b) showed the relationship between target up-and-down temperature difference and target SC. It is a characteristic view (Example 1). It is the flowchart which showed the blowing temperature control by air-conditioning ECU (Example 1). (A) is a characteristic diagram showing the relationship between the target upper / lower temperature difference and the target SC, and (b) is a characteristic diagram showing the relationship between the indoor condenser load and the target SC (Example 1). (Example 2) which is the block diagram which showed the vehicle air conditioner. (Example 2) which was the flowchart which showed the blowing temperature control by air-conditioning ECU. (A) is the characteristic figure which showed the relationship between target up-and-down temperature difference and target SC, (b) is the characteristic figure which showed the relationship between indoor condenser load and target SC (Example 2). (Example 3) which is the block diagram which showed the vehicle air conditioner. (Example 3) which was the flowchart which showed the blowing temperature control by air-conditioning ECU. (A) is a characteristic diagram showing the relationship between the indoor condenser load and the target SC, and (b) is a characteristic diagram showing the relationship between the target vertical temperature difference and the target SH (Example 3). (A) is explanatory drawing which showed the operating state in an air-conditioning duct, (b) is the Mollier diagram of a refrigerating cycle (prior art).

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
The present invention eliminates the warmth of the head of the occupant while minimizing the power of the electric compressor (power consumption of the electric motor) and secures the sensation of the foot of the occupant to provide a comfortable vehicle due to cold head heat. The purpose of performing indoor heating is to blow into the vehicle interior from the upper (FACE) outlet and the lower (FOOT) outlet compared to the FOOT mode in which the temperature difference of the air blown out from the plurality of FOOT outlets is reduced. The B / L mode in which the temperature difference of the air is increased is realized by including the first throttle opening degree control means for reducing the throttle opening degree of the first throttle.
In addition, the B / L mode is realized by including third throttle opening control means for reducing the throttle opening of the third throttle in the B / L mode than in the FOOT mode.

[Configuration of Example 1]
1 to 8 show an example (Example 1) of a control mode of the degree of supercooling (SC) of the refrigerant at the outlet of the indoor condenser in the vehicle air conditioner to which the present invention is applied.

  The vehicle air conditioner of the present embodiment air-conditions the interior of a vehicle such as an electric vehicle that travels using an electric motor (motor) as a power source, or a hybrid vehicle that travels using an internal combustion engine (engine) and a motor as power sources. Each air-conditioning means (actuator) of the air-conditioning unit is controlled by an air-conditioning control device (hereinafter referred to as an air-conditioning ECU) 1 so as to automatically control the temperature in the vehicle interior of the vehicle so as to always maintain the set temperature.

The air conditioning unit generates an airflow duct 2 that forms an air passage for guiding outside air (outside air) or inside air (inside air) of the vehicle into the vehicle interior, and an air flow toward the vehicle interior in the air conditioning duct 2 And a heat pump refrigeration cycle in which the refrigerant discharged from the electric compressor 3 circulates in the refrigerant circuit.
The refrigeration cycle includes an electric compressor 3, an indoor condenser 4, a first variable throttle means, an outdoor heat exchanger 5, a second variable throttle means, an indoor evaporator 6, an accumulator 7, and a refrigerant pipe that connects these in an annular shape. ing.
The first variable throttle means includes a first throttle hole through which the refrigerant flowing out from the outlet of the indoor condenser 4 passes, and a first throttle 11 for adjusting an opening area of the first throttle hole, that is, a throttle opening. Have.
The second variable throttle means includes a second throttle hole through which the refrigerant flowing out from the outlet of the outdoor heat exchanger 5 passes, and a second throttle 12 that adjusts the opening area of the second throttle hole, that is, the throttle opening. have.

The air conditioning duct 2 is disposed on the front side of the vehicle interior of the vehicle.
The air upstream side (windward side) of the air-conditioning duct 2 is a portion that constitutes a suction port switching box (inside / outside air switching box). The inside / outside air switching box is formed with an inside air suction port 14 for taking in the inside air and an outside air suction port 15 for taking in the outside air. Inside / outside air inlet port 14 and outside air inlet port 15, an inside / outside air switching door 16 is attached so as to be freely rotatable (turnable and swingable). The inside / outside air switching door 16 is driven by an actuator 17 such as a servo motor to switch the suction port mode to an inside air circulation mode, an outside air introduction mode, or the like. The inside / outside air switching door 16 constitutes inside / outside air switching means together with the inside / outside air switching box.

The most air downstream side (downwind side) of the air conditioning duct 2 is a part constituting the blowout outlet switching box. A defroster (DEF) opening (not shown), a face (FACE) opening 18 and a foot (FOOT) opening 19 are formed in the air outlet switching box.
The DEF opening is connected to a defroster duct (not shown), and a plurality of defrosters (mainly hot air) for blowing conditioned air (mainly hot air) to the inner surface of the front window glass at the end of the air downstream side of the defroster duct. DEF) An outlet is formed.
The FACE opening 18 is connected to a center face duct and a side face duct (both not shown). The center face duct and the side face duct are connected to the head and chest (upper body) of the vehicle occupant at the most downstream end of the air. A plurality of face (FACE) outlets for blowing out conditioned air (mainly cold air) are formed.

The FOOT opening 19 is connected to a foot duct (none of which is shown), and a plurality of air outlets (mainly hot air) for blowing out conditioned air (mainly hot air) to the foot of the vehicle occupant at the end of the foot duct on the most downstream side of the air. A foot (FOOT) outlet is formed.
A plurality of outlet switching doors 21 and 22 are rotatably attached (rotated and swinged) inside each outlet. These outlet switching doors 21 and 22 are driven by actuators 23 and 24 such as servo motors, respectively, to selectively open and close the DEF opening, the FACE opening 18 and the FOOT opening 19.
The plurality of outlet switching doors 21 and 22 have an outlet mode of a face (FACE) mode, a bi-level (B / L) mode, a foot (FOOY) mode, a foot differential (F / D) mode, or a defroster (DEF) mode. Switch to one.

The FACE mode is a blowout port mode in which only the FACE opening 18 is opened, and constitutes a first blowout mode in which the temperature difference between the air blown from the plurality of blowout ports into the vehicle compartment is reduced.
The B / L mode is a blowout mode that opens the FACE opening 18 and the FOOT opening 19 and constitutes a second blowout mode that increases the temperature difference of the air blown from the plurality of blowouts into the vehicle interior. .
The FOOT mode is an outlet mode that opens only the FOOT opening 19 and constitutes a first outlet mode.
In addition, the F / D mode is a blowout mode in which the DEF opening and the FOOT opening 19 are opened, and constitutes a second blowout mode.
The DEF mode is an outlet mode that opens only the DEF opening, and constitutes the first outlet mode.
In addition, the some blower outlet switching doors 21 and 22 comprise a blower outlet switching means with a blower outlet switching box.

The centrifugal blower is an indoor air blowing means for blowing the inside air or outside air to the indoor evaporator 6 and the indoor condenser 4, and is a scroll casing provided integrally with the air conditioning duct 2, and freely rotatable at the center of the scroll casing. And a blower motor 26 that rotationally drives the rotating shaft of the indoor blower fan 25.
The blower motor 26 controls the blower air volume (the rotational speed of the indoor fan 25) based on the blower terminal voltage applied through the blower motor drive circuit.

Inside the air conditioning duct 2, an air mix that adjusts the amount of air passing through the indoor condenser 4 (passing air volume) and the amount of air flowing through the bypass passage 27 that bypasses (bypasses) the indoor condenser 4 (bypass air volume). (A / M) A door 28 is installed.
The A / M door 28 is driven by an actuator 29 such as a servo motor, and opens and closes the air upstream side surface of the indoor condenser 4.
The A / M door 28 is attached to the air conditioning duct 2 so as to be freely rotatable (turnable and swingable). The A / M door 28 passes through the indoor condenser 4 depending on the stop position between the MAXCOOL position that bypasses all air from the indoor condenser 4 and the MAXHOT position that allows all air to pass through the indoor condenser 4. The air temperature ratio between the air amount and the air amount bypassing the indoor condenser 4 is changed to adjust the temperature of the air blown out into the vehicle interior.

Next, details of the refrigeration cycle of the present embodiment will be described with reference to FIGS. 1 and 2.
The refrigeration cycle includes an electric compressor 3, an indoor condenser 4, an outdoor heat exchanger 5, an indoor evaporator 6, an accumulator 7, a first variable throttle means having a first throttle 11, and a second variable having a second throttle 12. A diaphragm means or the like is provided.
The electric compressor 3 is an electric motor-driven compressor (electric compressor), and includes a compressor that compresses and discharges the sucked refrigerant, an electric motor that drives the compressor, and the like.

The electric motor is an electric motor that generates power (torque) that rotationally drives the rotating shaft of the compressor when electric power is supplied.
The electric motor rotates the compressor at a predetermined rotational speed by converting the voltage or frequency by an inverter 30 that is driven by power supplied from a battery that is a DC power source.
The inverter 30 shifts the rotational speed of the electric motor by variably controlling electric power (voltage or frequency) applied to the electric motor continuously or stepwise based on the control signal of the air conditioning ECU 1.
Therefore, in the electric compressor 3, the discharge capacity of the refrigerant discharged from the discharge unit of the electric compressor 3 continuously changes due to the change in the rotation speed of the electric motor. Thereby, the heating amount of the indoor condenser 4 is increased or decreased by increasing or decreasing the circulation amount of the refrigerant circulating in the refrigeration cycle, that is, the flow rate of the refrigerant flowing into the indoor condenser 4 or the flow rate of the refrigerant flowing into the indoor evaporator 6. The (heating) capacity and the cooling (cooling) capacity of the indoor evaporator 6 can be controlled.

The indoor condenser 4 is a first indoor heat exchanger that heats the air flowing through the air-conditioning duct 2 with a high-temperature and high-pressure refrigerant gas to condense and liquefy the refrigerant.
The indoor condenser 4 is installed on the upstream side (windward side) of the indoor evaporator 6 in the air conditioning duct 2, and high-temperature and high-pressure refrigerant discharged from the electric compressor 3 flows into the indoor condenser 4. Is a heat exchanger for heating that re-heats the air that has passed through the indoor evaporator 6 with the heat source for heating.
The indoor condenser 4 is disposed so as to partially block the cross section of the ventilation path of the unit case. A superheat (SH) region that is a high temperature region (superheated steam region) into which the high-temperature and high-pressure refrigerant gas discharged from the discharge portion of the electric compressor 3 flows is provided on the refrigerant inlet side of the indoor condenser 4. Yes.
Further, a subcool (SC) region, which is a low temperature region (supercooling region) through which the supercooled liquid refrigerant flows, is provided on the refrigerant outlet side of the indoor condenser 4.
Further, an isothermal region of the gas-liquid two-phase refrigerant is provided in an intermediate portion of the indoor condenser 4.

Here, in the air conditioning duct 2, the air passing through the SH region on the refrigerant inlet side of the indoor condenser 4 is blown out from the FOOT outlet, which is a high temperature outlet (lower outlet), into the vehicle interior. The indoor condenser 4 is arranged so that air passing through the SC region on the refrigerant outlet side of the indoor condenser 4 is blown out from the DEF outlet or the FACE outlet which is a low temperature side outlet (upper outlet) into the vehicle interior. .
The bypass flow path 27 opened and closed by the A / M door 28 is provided adjacent to the SC area on the refrigerant outlet side of the indoor condenser 4.

The outdoor heat exchanger 5 is installed outside the vehicle compartment (for example, a place where it is easy to receive traveling wind), and exchanges heat between the refrigerant flowing inside and the outside air blown by the electric outdoor fan.
The outdoor heat exchanger 5 has a function as an outdoor condenser (condenser) that exchanges heat with the outside air to condense and liquefy the refrigerant flowing from the first throttle 11 during the cooling operation. The outdoor heat exchanger 5 also has a function as an outdoor evaporator (evaporator) that exchanges heat from the first throttle 11 with the outside air to evaporate and vaporize it during heating operation and dehumidifying heating operation. . During the dehumidifying heating operation, the outdoor heat exchanger 5 may function as an outdoor condenser (subcool condenser) that further supercools the refrigerant flowing from the first throttle 11.
The electric outdoor blower is an outdoor blower that blows outside air to the outdoor heat exchanger 5, and includes an outdoor blower fan (not shown) that blows air to the outdoor heat exchanger 5, and a rotation shaft of the outdoor blower fan. It is comprised from the outdoor ventilation fan motor (not shown) rotated.
The outdoor air blowing fan motor controls the fan air volume (the rotational speed of the outdoor air blowing fan) based on the control voltage applied via the fan motor drive circuit.

The indoor evaporator 6 is installed in the air conditioning duct 2, and the low-temperature and low-pressure refrigerant decompressed by the second throttle 12 and the first throttle 11 in the cooling mode and the dehumidifying mode is exchanged with the air in the air conditioning duct 2. It is the 2nd indoor heat exchanger made to evaporate. As a result, the refrigerant flowing inside the indoor evaporator 6 takes the latent heat of evaporation from the air passing through the indoor evaporator 6 (heat absorption) and evaporates, whereby the air passing through the indoor evaporator 6 is cooled and dehumidified. .
The indoor evaporator 6 is a cooling heat exchanger that cools and dehumidifies the outside air or the inside air sucked into the air conditioning duct 2 by exchanging heat with the refrigerant while the A / C switch described later is ON.
The accumulator 7 functions as a gas-liquid separator that separates the refrigerant that has flowed into the liquid refrigerant and refrigerant gas, stores the liquid refrigerant, and supplies only the refrigerant gas to the electric compressor 3.

The first variable throttle means includes a first throttle 11 that adjusts the opening area of the first throttle hole communicating with the outlet of the indoor condenser 4, that is, the throttle opening.
The first throttle 11 is first decompression means for decompressing and expanding the refrigerant that has flowed out of the indoor condenser 4 during the heating mode and the dehumidifying heating mode. The first throttle 11 is a first variable throttle means that can change the opening area of the throttle hole through which the liquid refrigerant flowing out from the outlet of the indoor condenser 4 passes.
The first throttle 11 is installed upstream of the inlet portion of the outdoor heat exchanger 5 in the refrigerant flow direction, and the state of the refrigerant that has passed through the indoor condenser 4 (particularly the outlet refrigerant of the indoor condenser 4). The degree of supercooling: SC) is adjusted according to the throttle opening.
The first diaphragm 11 is configured to be driven by an electric actuator such as a servo motor that variably controls the opening area (throttle opening) of the first diaphragm hole.
The electric actuator is configured such that the first throttle 11 is fully closed (throttle opening = 0%), intermediate opening (0% <throttle opening <100%), and fully open (throttle opening = 100%). It is possible to adjust.

The second variable throttle means has a second throttle 12 for adjusting the opening area of the second throttle hole communicating with the outlet of the outdoor heat exchanger 5, that is, the throttle opening.
The second throttle 12 is a second decompression means for decompressing and expanding the refrigerant flowing out of the outdoor heat exchanger 5 in the cooling mode and the dehumidifying heating mode. Or it is the 2nd pressure reduction means which decompresses and expands the refrigerant | coolant which flowed out from the indoor condenser 4 at the time of dehumidification heating mode (refer Example 2 mentioned later: FIG. 9). The second throttle 12 is a second variable throttle means that can change the opening area of the throttle hole through which the liquid refrigerant flowing out from the outlet of the outdoor heat exchanger 5 passes.
The second diaphragm 12 is configured to be driven by an electric actuator such as a servo motor that variably controls the opening area (throttle opening) of the second diaphragm hole.
In the electric actuator, the throttle opening of the second throttle 12 is fully closed (throttle opening = 0%), intermediate opening (0% <throttle opening <100%), and fully open (throttle opening = 100%). It is possible to adjust.

The refrigeration cycle includes a first refrigerant circulation path, a second refrigerant circulation path, a third refrigerant circulation path, and a refrigerant path switching means.
The first refrigerant circulation path is a refrigerant for heating operation in which the electric compressor 3, the indoor condenser 4, the first throttle 11, the outdoor heat exchanger 5, and the accumulator 7 are sequentially connected in an annular shape during the heating operation so that the refrigerant circulates. Circuit.
In the second refrigerant circulation path, the electric compressor 3, the indoor condenser 4, the first throttle 11, the outdoor heat exchanger 5, the second throttle 12, the indoor evaporator 6 and the accumulator 7 are sequentially connected in an annular manner during the dehumidifying heating operation. The refrigerant circuit for dehumidifying and heating operation in which the refrigerant circulates.
In the third refrigerant circulation path, the electric compressor 3, the indoor condenser 4, the first throttle 11, the outdoor heat exchanger 5, the second throttle 12, the indoor evaporator 6, and the accumulator 7 are sequentially connected in an annular manner during the cooling operation. The refrigerant circuit for cooling operation in which the refrigerant circulates.

The refrigerant path switching means includes a first electromagnetic valve 31 that selectively switches to any one of the first to third refrigerant circulation paths, and a bypass pipe 34 that bypasses the indoor evaporator 6. .
The first electromagnetic valve 31 has a valve hole communicating with a bypass flow path formed in the bypass pipe 34, a valve body (valve) that opens and closes the valve hole, and an electromagnetic actuator that drives the valve in the fully open direction. ing. The electromagnetic actuator includes a solenoid having a coil that generates a magnetic force when energized.
When the solenoid coil is energized (turned on), the first solenoid valve 31 opens (fully opens) the bypass flow path formed in the bypass pipe 34. When energization of the solenoid coil is stopped (turned off), the bypass flow path formed in the bypass pipe 34 is closed (fully closed).

Here, the electric actuator that drives the first and second throttles 11 and 12, the electromagnetic actuator of the first electromagnetic valve 31, the actuator 17, the actuators 23 and 24, the blower motor 26, the actuator 29, and the inverter 30 are energized and controlled by the air conditioning ECU 1. It is configured to be.
The air conditioning ECU 1 includes a CPU for performing control processing and arithmetic processing, a storage device (memory such as RAM and ROM) for storing a control program or control logic and various data, an input circuit (input unit), an output circuit (output unit), It is a microcomputer having a known structure configured to include functions such as a power supply circuit, a timer, and a counter.

The air conditioning ECU 1 is configured such that sensor signals from various sensors are A / D converted by an A / D conversion circuit and then input to a microcomputer.
Here, the various sensors are an inside air temperature sensor (inside air temperature detecting means) that detects an air temperature in the vehicle interior of the vehicle (hereinafter referred to as an inside air temperature TR), and an air temperature outside the vehicle interior of the vehicle (hereinafter referred to as an outside air temperature TAM). An outside air temperature sensor (outside air temperature detecting means), a solar radiation sensor (sunlight amount detecting means) for detecting the amount of solar radiation entering the vehicle interior, and an A / M opening sensor (A / M) for detecting the opening degree of the A / M door 28 Opening degree detection means).
The various sensors are a refrigerant pressure sensor (refrigerant pressure detecting means) 41 for detecting the pressure of the refrigerant flowing out from the outlet of the indoor condenser 4 (condensation pressure, high pressure of the refrigeration cycle), and the outlet of the indoor condenser 4. Outlet refrigerant temperature sensor (indoor condenser outlet refrigerant temperature detecting means) 42 for detecting the temperature of refrigerant flowing out from the section, evaporator temperature sensor (indoor evaporator temperature detecting means) for detecting the temperature (TE) of the indoor evaporator 6 43 mag.

Here, the temperature (TAV) of the indoor condenser 4 uses a calculated value calculated from the sensor signal (detected value) of the refrigerant pressure sensor 41 and the sensor signal (detected value) of the outlet refrigerant temperature sensor 42. . Note that the detected value of the indoor condenser temperature sensor may be used as the temperature (TAV) of the indoor condenser 4. In this case, the temperature (TAV) of the indoor condenser 4 is the air temperature immediately downstream of the indoor condenser 4 or the surface temperature of the fins of the indoor condenser 4.
The detected value of the evaporator temperature sensor 43 is used for the temperature (TE) of the indoor evaporator 6. Specifically, it is the air temperature immediately after the downstream of the indoor evaporator 6 (or the temperature of the air passing through the bypass passage 27), or the surface temperature of the fins of the indoor evaporator 6.

In addition, the air conditioning ECU 1 performs A / D conversion after switch signals from various switches necessary for air conditioning operation provided in a control panel (air conditioning operation panel) and a remote controller (remote controller) are converted by an A / D conversion circuit. It is configured to be input to a microcomputer.
In addition to various switches, the control panel and the remote controller are provided with a display unit for displaying a set temperature in the passenger compartment, an air volume level, an outlet mode, an inlet mode, and the like. Here, the various switches are an auto switch that automatically controls each functional component of the air conditioning unit, and activation of the air conditioning unit. Also, an air conditioner (A / C) switch for commanding start and stop of the indoor evaporator 6 in the refrigeration cycle, a temperature setting switch for setting the temperature in the vehicle interior to a desired temperature, and an air volume for switching the air flow rate of the centrifugal blower A changeover switch or the like.

In addition, there are a suction port changeover switch for switching the suction port mode, a DEF switch for fixing the blower outlet mode to the DEF mode, a blower outlet changeover switch for switching the blower outlet mode, and the like.
The suction port changeover switch outputs a command to switch to the suction port mode of either the inside air circulation (REC) mode or the outside air introduction (FRS) mode.
Each time the push button is pressed, the air outlet changeover switch outputs a command for switching the air outlet mode in the order of FACE mode → B / L mode → FOOT mode → F / D mode → FACE mode.

The air conditioning ECU 1 calculates a supercooling degree calculating means for calculating (determining) the degree of supercooling (current SC) of the outlet refrigerant of the indoor condenser 4 and calculates the target supercooling degree (target SC) of the outlet refrigerant of the indoor condenser 4. A target subcooling degree calculating means for (determining) is provided.
The current SC is the pressure of the refrigerant flowing out from the outlet of the indoor condenser 4 (detected value of the refrigerant pressure sensor 41) and the temperature of the refrigerant flowing out of the outlet of the indoor condenser 4 (detected by the outlet refrigerant temperature sensor 42). Value). The current SC may be read from a map created by measuring these relationships in advance through experiments or the like.
When the (air conditioning) operation mode is the heating mode or the dehumidifying heating mode, the air conditioning ECU 1 controls the first throttle opening degree so that the throttle opening of the first throttle 11 is smaller in the B / L mode than in the FOOT mode. Have means.
When the operation mode is the heating mode, the air conditioning ECU 1 fully closes the throttle opening of the second throttle 12, and when the operation mode is the dehumidifying heating mode, the first throttle 11 decreases as the throttle opening decreases. Second throttle opening control means for increasing the throttle opening of the second throttle 12 is provided.

[Control Method of Example 1]
Next, a control method of the refrigeration cycle of this embodiment will be briefly described with reference to FIGS. Here, FIG. 3 is a flowchart showing a basic control process by the air conditioning ECU 1. The control routine of FIG. 3 is repeatedly executed every predetermined control cycle (timing) after the ignition switch is turned on.

When the timing for starting the control routine of FIG. 3 is reached, first, each switch signal is taken in from a temperature setting switch or the like on the control panel (step S1).
Next, sensor signals (detection values) output from various sensors such as an inside air temperature sensor, an outside air temperature sensor, a solar radiation sensor, an A / M opening sensor, a refrigerant pressure sensor 41, a refrigerant temperature sensor 42, and an evaporator temperature sensor 43. (Refrigerant pressure detecting means, refrigerant temperature detecting means, indoor evaporator temperature detecting means: step S2).

Next, a target blowing temperature (TAO) of the air blown out from the air conditioning duct 2 into the vehicle interior is calculated (determined) based on the following formula 1 stored (stored) in a memory in advance (target blowing temperature calculating means) : Step S3).
[Equation 1]
TAO = KSET × TSET-KR × TR-KAM × TAM-KS × TS + C
TSET is a set temperature set by the temperature setting unit. TR is the inside air temperature detected by the inside air temperature sensor. TAM is the outside temperature detected by the outside temperature sensor. TS is the amount of solar radiation detected by the solar radiation sensor.
However, KSET, KR, KAM, and KS are control gains. C is a constant for correction.

Next, a blower voltage (blower terminal voltage applied to the blower motor 26) corresponding to TAO is calculated (determined) from a map (not shown) stored (stored) in advance in the memory (step S4).
Here, when the air volume changeover switch is operated by an occupant, that is, in the case of manual control, the blower voltage is fixed according to the operation position of the airflow changeover section.

Next, a suction port mode corresponding to TAO is calculated (determined) from a map (not shown) previously stored (stored) in the memory (step S5).
Here, in the determination of the suction port mode, in the case of auto control, the TAO is switched from a low temperature to a high temperature so that the internal air circulation (REC) mode, the internal / external air introduction (semi-inside air) mode, and the external air introduction (FRS) mode are set. To be determined. In addition, when the suction port changeover switch is operated by a passenger, that is, in the case of manual control, the suction port mode is fixed to either the inside air circulation mode or the outside air introduction mode. The suction port mode may be determined only by manual control.

Next, the air outlet mode corresponding to TAO is calculated (determined) from a map (not shown) stored (stored) in the memory in advance (step S6).
Here, in the determination of the outlet mode, in the case of auto control, the TAO is determined to be in the FACE mode, the B / L mode, and the FOOT mode from a low temperature to a high temperature. In addition, when the air outlet changeover switch is operated by a passenger, that is, in the case of manual control, the air outlet mode set by the air outlet changeover switch is fixed. Note that the air outlet mode may be determined only by manual control.

Next, the control routine of FIG. 4 is activated to determine (determine) the operation mode determination, current indoor condenser temperature (TAV), target indoor condenser temperature (TAO), and target indoor evaporator temperature (TEO). (Step S7).
Next, the control routine of FIG. 5 and FIG. 7 is started, and post-evaporation temperature control and blowout temperature control are executed (step S8).
Next, the solenoid valve drive circuit of the first solenoid valve 31, the motor drive circuit of the actuator 17, and the motor drive of the actuators 23, 24, and 29 are obtained so that the control states calculated or determined in steps S2 to S8 are obtained. A control signal is output to the circuit, the blower drive circuit of the centrifugal blower, and the inverter 30 (step S9). Thereafter, the control routine of FIG. 3 is exited.

[Operation mode determination control of Embodiment 1]
Next, when it is time to enter the control routine of FIG. 4, an operation mode corresponding to TAO is calculated (determined) from a map (not shown) previously stored (stored) in the memory (step S11).
Here, in the determination of the operation mode, in the case of auto control, the target blowing temperature (TAO) is determined to be the cooling mode, the dehumidifying heating mode, and the heating mode from a low temperature to a high temperature.
Alternatively, when the target blowout temperature (TAO) is determined to be the cooling mode and the heating mode from the low temperature to the high temperature, and the A / C switch is turned off when the cooling mode is selected, the heating mode is selected. You may make it do. Further, when the heating mode is selected, the dehumidifying heating mode may be selected if the A / C switch is turned on, and the heating mode may be selected if the A / C switch is turned off. The operation mode may be determined only by manual control.

Next, it is determined whether or not the operation mode is a cooling mode (step S12). If the determination result is YES, the target indoor evaporator temperature (TEO) is calculated (determined) from the target outlet temperature (TAO) (target indoor evaporator calculating means: step S13). This TEO may be read from a map created by measuring these relationships in advance through experiments or the like.
Specifically, TAO = TEO. Alternatively, when TAO is, for example, 15 ° C. or higher, TEO is set at, for example, 12 ° C., and when TAO is, for example, 5 ° C. or lower, TEO is set at, for example, 0 ° C., and between 5 ° C. and 15 ° C., 0 ° C. The TEO is set so as to continuously vary from 1 to 12 ° C.

Next, the target door opening degree of the A / M door 28 is set to the MAXCOOL position which is the maximum cooling position (the hot air flow path passing through the indoor condenser 4 is fully closed and the bypass flow path 27 is fully opened). Degree control means: step S14).
Next, the first solenoid valve 31 is turned OFF to be fully closed, the first throttle 11 is turned OFF to be fully opened, and the throttle opening of the second throttle 12 is set to a control opening controlled by the air conditioning ECU 1 (step) S15). Thereafter, the control routine of FIG. 4 is exited.

If the determination result in step S12 is NO, the target outlet temperature (TAO) is converted into the target indoor condenser temperature (TAO) and stored (stored) in the memory (target indoor condenser computing means: Step S16).
Note that, when the operation mode is the heating mode or the dehumidifying heating mode, the target indoor condenser temperature (TAO) may be directly determined based on the above equation (1).
Next, the target door opening degree of the A / M door 28 is set to the MAXHOT position which is the maximum heating position (the hot air passage passing through the indoor condenser 4 is fully opened and the bypass passage 27 is fully closed) (door opening). Degree control means: step S17).

Next, the current indoor condenser temperature (TAV) is calculated (determined) from the sensor signal (detected value) of the refrigerant pressure sensor 41 and the sensor signal (detected value) of the outlet refrigerant temperature sensor 42 (condenser temperature detection). (Calculation) Means: Step S18). This TAV may be read from a map created by measuring these relationships in advance through experiments or the like.
In this embodiment, it is read from a map (not shown) stored (stored) in the memory in advance.
Next, it is determined whether or not the operation mode is the heating mode (step S19). If the determination result is YES, the first solenoid valve 31 is turned on and fully opened, the throttle opening of the first throttle 11 is set to a control opening controlled by the air conditioning ECU 1, and the second throttle 12 is turned on. Then, it is fully closed (step S20). Thereafter, the control routine of FIG. 4 is exited.

If the determination result in step S19 is NO, that is, if the operation mode is the dehumidifying heating mode, the target indoor evaporator temperature (TEO) is calculated (determined) from TR or TAM (target evaporator temperature calculation) Means: Step S21). This TEO may be read from a map created by measuring these relationships in advance through experiments or the like.
In this embodiment, it is read from a map (not shown) stored (stored) in the memory in advance.
Specifically, TEO = 0 ° C. Alternatively, TEO = TR-5 ° C. or TEO = TAM-5 ° C.
Next, the first solenoid valve 31 is turned OFF and fully closed, the throttle opening of the first throttle 11 is set to a control opening controlled by the air conditioning ECU 1, and the throttle opening of the second throttle 12 is set by the air conditioning ECU 1. The controlled opening is set to be controlled (first and second throttle opening control means: step S22). Thereafter, the control routine of FIG. 4 is exited.

[Blowout Temperature Control During Dehumidifying Heating Operation of Example 1]
When the dehumidifying and heating mode is selected as the operation mode, the control routine of FIG. 5 is activated to perform post-evaporation temperature control (discharge capacity control means: step S31).
Specifically, the rotational speed of the electric motor of the electric compressor 3 is adjusted so that the current indoor evaporator temperature (temperature sensor value: TE) becomes the target indoor evaporator temperature (TEO). That is, the target rotational speed of the electric compressor 3 is determined.
The rotational speed of the electric compressor 3 (the discharge capacity of the refrigerant discharged from the electric compressor 3) may be read from a map created by measuring these relationships in advance through experiments or the like.
In this embodiment, it is read from a map (not shown) stored (stored) in the memory in advance.

Next, high temperature side (FOOT) blowing temperature control is executed (first and second throttle opening control means: step S32).
Specifically, the throttle opening of the first throttle 11 and the second throttle so that the current indoor condenser temperature (calculated value based on the pressure sensor value: TAV) becomes the target indoor condenser temperature (TAO). An opening pattern (opening ratio) with 12 throttle openings is determined (adjusted).
That is, the temporary target throttle opening (A) of the first throttle 11 and the temporary target throttle opening (B) of the second throttle 12 are calculated (determined) from the current indoor condenser temperature (TAV).
The temporary target throttle opening (A) of the first throttle 11 and the temporary target throttle opening (B) of the second throttle 12 may be read from a map created by measuring these relationships in advance through experiments or the like. .
In this embodiment, reading is performed from a map (see FIG. 6A) stored (stored) in a memory in advance.

Next, it is determined whether or not the air outlet mode is the B / L mode (step S33). If this determination is YES, low temperature side (FACE) blowout temperature control is executed (first and second throttle opening control means: step S34).
Specifically, a target SC (target supercooling degree SC of the refrigerant at the outlet of the indoor condenser 4) is calculated (determined).
The target SC may be read from an upper and lower temperature difference map (see FIG. 6B) created by measuring the relationship with the target upper and lower temperature difference in advance through experiments or the like.
In the present embodiment, reading is performed from a vertical temperature difference map (see FIG. 6B) stored (stored) in a memory in advance. When the target vertical temperature difference in FIG. 6B is a preset target vertical temperature difference (C value: 10 to 15 degrees, for example), the target SC is a D value corresponding to the C value.
Next, the opening degree correction coefficient α of the first throttle 11 and the second throttle 12 is calculated so that the current SC (current supercooling degree SC of the outlet refrigerant of the indoor condenser 4: calculated value) becomes the target SC. (decide.

Next, based on the following formulas 2 and 3 stored (stored) in the memory in advance, the final target throttle opening (EVH) of the first throttle 11 and the final target throttle opening (EVH) of the second throttle 12 ( EVC) is determined (first and second throttle opening control means: step S35). Thereafter, the control routine of FIG. 5 is exited.
[Equation 2]
EVH = A × α
[Equation 3]
EVC = B × α
If the determination result in step S33 is NO, the opening correction coefficient (α) of the first throttle 11 is set to 1, and the opening correction coefficient (α) of the second throttle 12 is set to 1. (First and second throttle opening control means: step S36). Thereafter, the control process of step S35 is executed.

[Blowout temperature control during heating operation of Example 1]
When the operation mode is the dehumidifying and heating mode, the control routine of FIG. 7 is started and the high temperature side (FOOT) blowing temperature control is executed (discharge capacity control means: step S41).
Specifically, the rotational speed of the electric compressor 3 is adjusted so that the current indoor condenser temperature (calculated value based on the pressure sensor value: TAV) becomes the target indoor condenser temperature (TAO). That is, the target rotation speed is determined.
The rotational speed of the electric compressor 3 (the discharge capacity of the refrigerant discharged from the electric compressor 3) may be read from a map created by measuring these relationships in advance through experiments or the like.
In this embodiment, it is read from a map (not shown) stored (stored) in the memory in advance.

Next, it is determined whether or not the air outlet mode is the B / L mode (step S42). When this determination result is YES, low temperature side (FACE) blowing temperature control is executed (first throttle opening degree control means: step S43). Thereafter, the control routine of FIG. 7 is exited.
Specifically, a target SC (target supercooling degree SC of the refrigerant at the outlet of the indoor condenser 4) is calculated (determined).
The target SC may be read from an upper and lower temperature difference map (see FIG. 8A) created by measuring the relationship with the target upper and lower temperature difference in advance through experiments or the like.
In the present embodiment, reading is performed from an upper and lower temperature difference map (see FIG. 8A) stored (stored) in a memory in advance. When the target vertical temperature difference in FIG. 8A is a preset target vertical temperature difference (E value: 10 to 15 degrees, for example), the target SC is an F value corresponding to the E value.
Next, the throttle opening degree of the first throttle 11 is adjusted so that the current SC (the current degree of subcooling of the outlet refrigerant of the indoor condenser 4 is the calculated value) becomes the target SC. That is, the target first throttle opening degree of the first throttle 11 is determined.

If the determination result in step S43 is NO, efficiency control is executed (first throttle opening control means: step S44). Thereafter, the control routine of FIG. 7 is exited.
Specifically, a target SC (target supercooling degree SC of the refrigerant at the outlet of the indoor condenser 4) is calculated (determined).
The target SC is based on an optimum efficiency map (see FIG. 8B) created by measuring the relationship with the indoor condenser load (for example, TE, TR, or TAM which is the suction temperature of the indoor condenser 4) in advance through experiments or the like. You may make it read.
In this embodiment, reading is performed from an optimum efficiency map (see FIG. 8B) stored (stored) in a memory in advance. In addition, when the indoor condenser load of FIG.8 (b) is made into the preset indoor condenser load (G value), target SC becomes H value corresponding to G value.
Next, the throttle opening degree of the first throttle 11 is adjusted so that the current SC (the current degree of subcooling of the outlet refrigerant of the indoor condenser 4 is the calculated value) becomes the target SC. That is, the target first throttle opening degree of the first throttle 11 is determined.

[Operation of Example 1]
Next, the operation of the vehicle air conditioner (Embodiment 1) to which the present invention is applied will be briefly described with reference to FIGS.

During the cooling operation in which the cooling mode (third refrigerant circulation path) is selected as the operation mode, the FACE mode or the B / L mode is selected as the outlet mode, and the first throttle 11 of the refrigeration cycle is fully opened, The throttle 12 becomes the control opening, and the first electromagnetic valve 31 is closed.
As a result, the high-temperature and high-pressure refrigerant gas discharged from the discharge portion of the electric compressor 3 is converted into the indoor condenser 4 → the first throttle 11 → the outdoor heat exchanger 5 → the second throttle 12 → the indoor evaporator 6 → the accumulator 7 → The refrigerant circulates in the order of the electric compressor 3.
At this time, the opening degree of the A / M door 28 is 0% that fully closes the hot air passage that passes through the indoor condenser 4 and fully opens the bypass passage 27 that bypasses the indoor condenser 4. The air cooled by the evaporation heat of the refrigerant in the evaporator 6 passes through the bypass passage 27. As a result, the air that has passed through the indoor evaporator 6 is blown into the vehicle interior mainly through the FACE opening 31 without heat exchange with the refrigerant flowing into the indoor condenser 4, thereby cooling the vehicle interior. The

At the time of heating operation in which the heating mode (first refrigerant circulation path) is selected as the operation mode, the FOOT mode or the B / L mode is selected as the outlet mode, and the first throttle 11 of the refrigeration cycle becomes the control opening, The second throttle 12 is fully closed and the first electromagnetic valve 31 is opened.
Thereby, the high-temperature and high-pressure refrigerant gas discharged from the discharge part of the electric compressor 3 is converted into the indoor condenser 4 → the first throttle 11 → the outdoor heat exchanger 5 → the first electromagnetic valve 31 → the accumulator 7 → the electric compressor 3. The refrigerant circulates in this order.
At this time, the opening degree of the A / M door 28 is 100% that fully opens the hot air passage that passes through the indoor condenser 4 and fully closes the bypass passage 27 that bypasses the indoor condenser 4. Thereby, the air that has passed through the indoor evaporator 6 is heated by the indoor condenser 4 to the high-temperature refrigerant gas discharged from the discharge portion of the electric compressor 3.
The heated air is blown into the vehicle interior from the FACE opening 18 and the FOOT opening 19 to heat the vehicle interior.

During the heating operation in which the dehumidifying heating mode (second refrigerant circulation path) is selected as the operation mode, the FOOT mode or the B / L mode is selected as the outlet mode, and the first and second throttles 11 and 12 of the refrigeration cycle are further selected. Becomes the control opening, and the first electromagnetic valve 31 is closed.
As a result, the high-temperature and high-pressure refrigerant gas discharged from the discharge portion of the electric compressor 3 is converted into the indoor condenser 4 → the first throttle 11 → the outdoor heat exchanger 5 → the second throttle 12 → the indoor evaporator 6 → the accumulator 7 → The refrigerant circulates in the order of the electric compressor 3.
In this refrigerant circuit for dehumidifying and heating operation, when the refrigerant passes through the first throttle 11, the pressure is reduced to the intermediate pressure of the refrigeration cycle, and when the refrigerant passes through the second throttle 12, the pressure is reduced to the low pressure of the refrigeration cycle. Is done.
At this time, the opening degree of the A / M door 28 is 100% that fully opens the hot air passage that passes through the indoor condenser 4 and fully closes the bypass passage 27 that bypasses the indoor condenser 4. As a result, the air that has been cooled and dehumidified by the indoor evaporator 6 is reheated when passing through the indoor condenser 4 and blown out from the FACE opening 18 or the FOOT opening 19 into the vehicle interior, thereby dehumidifying the vehicle interior. Heated.

[Features of Example 1]
The heat pump type air conditioner that combines the “reheat type temperature control” and the “air mix type temperature control” of the conventional device, the A / M door 111 is positioned at the intermediate position during the heating (dehumidification) operation and in the B / L mode. To increase the pressure of the indoor condenser 105 (high pressure of the refrigeration cycle) by reducing the amount of air passing through the indoor condenser 105 and ensuring the necessary heat dissipation in the indoor condenser 105, In order to make a difference in the upper and lower temperature from the FOOT outlet, there is a problem that the power of the compressor (power consumption of the electric motor) increases.

Therefore, while keeping the power of the compressor (power consumption of the electric motor that drives the electric compressor 3) to a minimum, it eliminates the hot feeling of the occupant's head and secures the sensation of the occupant's feet, For the purpose of providing a vehicle air conditioner capable of performing comfortable vehicle interior heating, firstly, the A / M door 28 is fully opened (bypass passage 27 is fully closed), and “reheat-type temperature control (temperature Control) ”.
Here, when the operation mode is the heating mode (heating operation) and the outlet mode is the B / L mode, the low speed pressure of the refrigeration cycle is controlled by adjusting the rotation speed of the electric compressor 3 so that TAV becomes TAO. To do. Then, a target SC based on the target vertical temperature difference is set, and the throttle opening of the first throttle 11 is adjusted so that the current SC becomes the set target SC. At this time, the opening degree of the first diaphragm 11 is smaller than that in the FOOT mode. Thereby, the degree of supercooling of the outlet refrigerant of the indoor condenser 4 is controlled.

In addition, when the operation mode is the dehumidifying heating mode (dehumidifying heating operation) and the outlet mode is the FOOT mode, the low pressure of the refrigeration cycle is adjusted by adjusting the rotation speed of the electric compressor 3 so that TE becomes TEO. To control. And the high pressure of a refrigerating cycle is controlled by the combination of the throttle opening degree of the two 1st, 2nd throttles 11 and 12 so that it may become the target blowing temperature of the air which blows off from a FOOT blower outlet to a vehicle interior.
Further, when the operation mode is the dehumidifying heating mode (dehumidifying heating operation) and the outlet mode is the B / L mode, the low speed pressure of the refrigeration cycle is adjusted by adjusting the rotational speed of the electric compressor 3 so that TE becomes TEO. Control. And while controlling the high pressure of a refrigerating cycle with the opening ratio of the two 1st, 2nd apertures 11 and 12 so that it may become the target blowing temperature of the air which blows off from a FOOT blower outlet, the target of the air which blows off from a FACE blower outlet The two first and second throttles 11 are maintained while maintaining the opening ratio of the two first and second throttles 11 and 12 determined as described above so that the temperature is lower than the FOOT outlet. , 12 is adjusted in the throttle direction to control the degree of supercooling (SC) of the refrigerant at the outlet of the indoor condenser 4.

Here, the operating state in the air conditioning duct 2 in the dehumidifying heating operation is shown in FIG. 2A, and the Mollier diagram of the refrigeration cycle is shown in FIG.
In the vehicle air conditioner of the first embodiment, the A / M door 28 is set to the fully open (MAXHOT) position. The temperature of the air that passed through the SH region on the refrigerant inlet side of the indoor condenser 4 passed through the SC region on the refrigerant outlet side of the indoor condenser 4 while suppressing the increase in the pressure of the indoor evaporator 6. The temperature of the air is 27 ° C.
Here, although the temperatures are 61 ° C. and 27 ° C., which are lower than those of the conventional device, a temperature difference of 34 degrees larger than that of the conventional device can be obtained without increasing the high pressure of the refrigeration cycle. A predetermined temperature difference (10 degrees) can be created as the upper and lower temperature difference between the communicating FACE outlet and the FOOT outlet 19 communicating with the FOOT opening 19.
This data shows that the temperature of the air introduced into the indoor condenser 4 is 0 ° C., the flow rate of air supplied to the indoor evaporator 6 is 150 m ³ / h, and the flow rate of air supplied to the indoor condenser 4 is 150 m ³ / h. It is a thing of the state.

[Effect of Example 1]
As described above, in the vehicle air conditioner of the first embodiment, the air passing through the SH region on the refrigerant inlet side of the indoor condenser 4 is blown out from the FOOT outlet through the FOOT opening 19 into the vehicle interior. The indoor condenser 4 is arranged in the air conditioning duct 2 so that air passing through the SC region on the refrigerant outlet side of the indoor condenser 4 is blown out from the FACE outlet through the FACE opening 18 into the vehicle interior.
In the heating operation or the dehumidifying heating operation, the A / M door 28 is set to MAXHOT, and the B / L mode is at least one of the two first and second throttle openings when compared with the FOOT mode. Control is performed so that the throttle opening of one throttle 11 is reduced.

  Thus, the temperature distribution of the air that has passed through the indoor condenser 4 (SC) is adjusted by setting the A / M door 28 to the fully open (MAXHOT) position and adjusting the degree of supercooling (SC) of the outlet refrigerant of the indoor condenser 4 ( For example, a temperature distribution that continuously changes from a low temperature range to a high temperature range) is generated. As a result, the temperature of the conditioned air blown from the FACE outlet to the vehicle interior and the FOOT outlet from the FOOT outlet while ensuring the necessary heat dissipation in the indoor condenser 4 without increasing the pressure of the indoor condenser 4 compared to the conventional apparatus. A temperature difference (for example, 10 to 15 degrees) can be made between the temperature of the conditioned air blown out to the air. Thereby, since the increase in the power consumption of the electric motor (compressor power) of the electric compressor 3 can be suppressed, the coefficient of performance (system COP) of the refrigeration cycle can be improved.

Therefore, while minimizing the increase in power consumption of the electric motor that drives the electric compressor 2, the feeling of warmth at the head of the occupant is eliminated, and the warmth of the feet of the occupant is ensured, so that the comfort of the passenger compartment due to the cold head heat Heating operation or dehumidifying heating operation can be performed.
In addition, from the viewpoint of using the temperature distribution of the air that has passed through the indoor condenser 4, the power (consumption) of the electric compressor 3 is separated from the means for controlling the degree of supercooling (SC) of the refrigerant at the outlet of the indoor condenser 4. Although an effect of suppressing an increase in electric power) cannot be expected, a means (Example 3) for controlling the degree of superheat (SH) of the inlet refrigerant of the indoor condenser 4 may be added.

[Configuration of Example 2]
FIGS. 9 to 11 show an example (Example 2) of a control mode of the degree of supercooling (SC) of the refrigerant at the outlet of the indoor condenser in the vehicle air conditioner to which the present invention is applied.
Here, the same reference numerals as those in the first embodiment indicate the same configuration or function, and the description thereof is omitted.

The air conditioning unit of the present embodiment guides the air passing through the SH region on the refrigerant inlet side of the indoor condenser 4 to the FOOT opening 19 that communicates with the FOOT outlet that is the high temperature side outlet (lower outlet). The FOOT opening 19 is disposed near the SH area on the refrigerant inlet side of the indoor condenser 4.
The air conditioning unit also has a DEF opening or a FACE opening that communicates air passing through the SC region on the refrigerant outlet side of the indoor condenser 4 to a DEF outlet or a FACE outlet that is a low temperature side outlet (upper outlet). The DEF opening or the FACE opening 18 is arranged near the SC area on the refrigerant outlet side of the indoor condenser 4 so as to lead to 18.

The refrigeration cycle includes a first refrigerant circulation path, a second refrigerant circulation path, a third refrigerant circulation path, and a refrigerant path switching means.
The first refrigerant circulation path is a refrigerant for heating operation in which the electric compressor 3, the indoor condenser 4, the first throttle 11, the outdoor heat exchanger 5, and the accumulator 7 are sequentially connected in an annular shape during the heating operation so that the refrigerant circulates. Circuit.
In the second refrigerant circulation path, during the dehumidifying heating operation, the electric compressor 3, the indoor condenser 4, the first throttle 11, the outdoor heat exchanger 5 and the accumulator 7 are sequentially connected in an annular manner so that the refrigerant circulates. The refrigerant circuit for electric motor 3, the indoor condenser 4, the second throttle 12, the indoor evaporator 6, and the accumulator 7 are sequentially connected in an annular manner, and the refrigerant circuit for dehumidifying and heating operation in which the refrigerant circulates is configured. .
In the third refrigerant circulation path, the electric compressor 3, the indoor condenser 4, the first throttle 11, the outdoor heat exchanger 5, the second throttle 12, the indoor evaporator 6, and the accumulator 7 are sequentially connected in an annular manner during the cooling operation. The refrigerant circuit for cooling operation in which the refrigerant circulates.

The refrigerant path switching means is a bypass pipe 34 that bypasses the first and second electromagnetic valves 31 and 32 and the indoor evaporator 6 that selectively switches to any one of the first to third refrigerant circulation paths. Further, a bypass pipe 35 that bypasses the outdoor heat exchanger 5 and a check valve 36 that prevents the refrigerant from flowing backward are provided.
The first electromagnetic valve 31 has the same configuration as that of the first embodiment.
The second electromagnetic valve 32 has a valve hole communicating with a bypass flow path formed in the bypass pipe 35, a valve body (valve) for opening and closing the valve hole, and an electromagnetic actuator for driving the valve in a fully open direction. ing. The electromagnetic actuator includes a solenoid having a coil that generates a magnetic force when energized.
When the solenoid coil is energized (turned on), the second solenoid valve 32 opens (fully opens) the bypass flow path formed in the bypass pipe 35. When energization of the solenoid coil is stopped (off), the bypass flow path formed in the bypass pipe 35 is closed (fully closed).

Here, the electric actuators that drive the first and second throttles 11 and 12, the electromagnetic actuators of the first and second electromagnetic valves 31 and 32, the actuator 17, the actuators 23 and 24, the blower motor 26, the actuator 29, and the inverter 30 are The energization is controlled by the air conditioning ECU 1.
In the inlet circuit of the air conditioning ECU 1, as in the first embodiment, an inside air temperature sensor, an outside air temperature sensor, a solar radiation sensor, an A / M opening sensor, a refrigerant pressure sensor 41, an outlet refrigerant temperature sensor 42, an evaporator temperature sensor 43, and the like. Is connected.

[Control Method of Example 2]
Next, the control method of the refrigerating cycle of the present embodiment will be briefly described with reference to FIGS.

When the dehumidifying and heating mode is selected as the operation mode, the control routine of FIG. 10 is activated to execute the high temperature side (FOOT) blowing temperature control (discharge capacity control means: step S51).
Specifically, the rotational speed of the electric motor of the electric compressor 3 is adjusted so that the current indoor condenser temperature (calculated value based on the pressure sensor value: TAV) becomes the target indoor condenser temperature (TAO). . That is, the target rotational speed of the electric compressor 3 is determined.
The rotational speed of the electric compressor 3 (the discharge capacity of the refrigerant discharged from the electric compressor 3) may be read from a map created by measuring these relationships in advance through experiments or the like.
In this embodiment, it is read from a map (not shown) stored (stored) in the memory in advance.

Next, post-evaporation temperature control (flow rate control) is executed (second throttle opening control means: step S52).
Specifically, the throttle opening degree of the second throttle 12 is adjusted so that the degree of superheat (SH) of the outlet refrigerant of the indoor evaporator 6 becomes a predetermined value. That is, the target second throttle opening degree of the second throttle 12 is determined.
Next, it is determined whether or not the air outlet mode is the B / L mode (step S53). When this determination result is YES, low temperature side (FACE) blowing temperature control is executed (first throttle opening degree control means: step S54). Thereafter, the control routine of FIG. 10 is exited.
Specifically, the target SC (the target subcooling degree SC of the outlet refrigerant of the indoor condenser 4) is calculated. The target SC may be read from an upper and lower temperature difference map (see FIG. 11A) created by measuring the relationship with the target upper and lower temperature difference in advance through experiments or the like.
In the present embodiment, reading is performed from an upper and lower temperature difference map (see FIG. 11A) stored (stored) in a memory in advance. When the target vertical temperature difference in FIG. 11A is a preset target vertical temperature difference (I value: 10 to 15 degrees, for example), the target SC is a J value corresponding to the I value.
Next, the throttle opening degree of the first throttle 11 is adjusted so that the current SC (the current degree of subcooling of the outlet refrigerant of the indoor condenser 4 is the calculated value) becomes the target SC. That is, the target first throttle opening degree of the first throttle 11 is determined.

Moreover, when the determination result of step S53 is NO, efficiency control is executed (first throttle opening control means: step S55). Thereafter, the control routine of FIG. 10 is exited.
Specifically, the target SC (the target subcooling degree SC of the outlet refrigerant of the indoor condenser 4) is calculated. The target SC is based on an optimum efficiency map (see FIG. 11B) created by measuring the relationship with the indoor condenser load (for example, TE, TR, or TAM, which is the suction temperature of the indoor condenser 4) in advance through experiments or the like. You may make it read.
In this embodiment, it is read from an optimum efficiency map (see FIG. 11B) stored (stored) in a memory in advance. In addition, when the indoor condenser load of FIG.11 (b) is made into the preset indoor condenser load (K value), target SC becomes L value corresponding to K value.
Next, the throttle opening of the first throttle 11 is adjusted so that the current SC becomes the target SC. That is, the target first throttle opening degree of the first throttle 11 is determined.

[Features of Example 2]
As described above, in the vehicle air conditioner of the second embodiment, the air passing through the SH region on the refrigerant inlet side of the indoor condenser 4 is blown out from the FOOT outlet through the FOOT opening 19 into the vehicle interior. The indoor condenser 4 is arranged in the air conditioning duct 2 so that air passing through the SC region on the refrigerant outlet side of the indoor condenser 4 is blown out from the FACE outlet through the FACE opening 18 into the vehicle interior.

During the heating operation in which the dehumidifying heating mode (second refrigerant circulation path) is selected as the operation mode, the FOOT mode or the B / L mode is selected as the outlet mode, and the first and second throttles 11 and 12 of the refrigeration cycle are further selected. Becomes the control opening, and the first and second electromagnetic valves 31 and 32 are opened.
Thereby, the high-temperature and high-pressure refrigerant gas discharged from the discharge part of the electric compressor 3 is converted into the indoor condenser 4 → the first throttle 11 → the outdoor heat exchanger 5 → the first electromagnetic valve 31 → the accumulator 7 → the electric compressor 3. The refrigerant circulates in this order.
Further, the refrigerant circulates in the order of the electric compressor 3 → the indoor condenser 4 → the second electromagnetic valve 32 → the second throttle 12 → the indoor evaporator 6 → the accumulator 7 → the electric compressor 3.

At this time, the opening degree of the A / M door 28 is 100% that fully opens the hot air passage that passes through the indoor condenser 4 and fully closes the bypass passage 27 that bypasses the indoor condenser 4. As a result, the air that has been cooled and dehumidified by the indoor evaporator 6 is reheated when passing through the indoor condenser 4 and blown out from the FACE opening 18 or the FOOT opening 19 into the vehicle interior, thereby dehumidifying the vehicle interior. Heated.
In the refrigerant flow dehumidifying heating operation as described above, when the outlet mode is the B / L mode, the target SC is set based on the necessary vertical temperature difference so that the current SC becomes the set target SC. The throttle opening of the first throttle 11 is adjusted.
When the outlet mode is the FOOT mode, the target SC with the optimum cycle efficiency is determined, and the throttle opening of the first throttle 11 is adjusted so that the current SC becomes the set target SC.

As described above, the vehicle air conditioner of the second embodiment has the same effects as the first embodiment.
In addition, from the viewpoint of using the temperature distribution of the air that has passed through the indoor condenser 4, the power (consumption) of the electric compressor 3 is separated from the means for controlling the degree of supercooling (SC) of the refrigerant at the outlet of the indoor condenser 4. Although an effect of suppressing an increase in electric power) cannot be expected, a means (Example 3) for controlling the degree of superheat (SH) of the inlet refrigerant of the indoor condenser 4 may be added.

[Configuration of Example 3]
FIGS. 12 to 14 show examples of control modes of the degree of superheat (SH) of the inlet refrigerant of the indoor condenser and the degree of supercooling (SC) of the outlet refrigerant of the indoor condenser in the vehicle air conditioner to which the present invention is applied. Example 3) is shown.
Here, the same reference numerals as those in the first and second embodiments indicate the same configuration or function, and the description thereof will be omitted.

The air conditioning unit of the present embodiment guides the air passing through the SH region on the refrigerant inlet side of the indoor condenser 4 to the FOOT opening 19 that communicates with the FOOT outlet that is the high temperature side outlet (lower outlet). The FOOT opening 19 is disposed near the SH area on the refrigerant inlet side of the indoor condenser 4.
The air conditioning unit also has a DEF opening or a FACE opening that communicates air passing through the SC region on the refrigerant outlet side of the indoor condenser 4 to a DEF outlet or a FACE outlet that is a low temperature side outlet (upper outlet). The DEF opening or the FACE opening 18 is arranged near the SC area on the refrigerant outlet side of the indoor condenser 4 so as to lead to 18.

The refrigeration cycle includes a first refrigerant circulation path, a second refrigerant circulation path, a third refrigerant circulation path, and a refrigerant path switching means.
In the first refrigerant circulation path, during the heating operation, the electric compressor 3, the third throttle 13, the indoor condenser 4, the first throttle 11, the outdoor heat exchanger 5, and the accumulator 7 are sequentially connected in an annular shape so that the refrigerant circulates. This is a refrigerant circuit for heating operation.
During the dehumidifying and heating operation, the second refrigerant circulation path includes the electric compressor 3, the third throttle 13, the indoor condenser 4, the first throttle 11, the outdoor heat exchanger 5, the second throttle 12, the indoor evaporator 6, and the accumulator 7. Is a refrigerant circuit for dehumidifying and heating operation in which the refrigerant is sequentially connected in an annular shape and the refrigerant circulates.
During the cooling operation, the third refrigerant circulation path includes the electric compressor 3, the third throttle 13, the indoor condenser 4, the first throttle 11, the outdoor heat exchanger 5, the second throttle 12, the indoor evaporator 6 and the accumulator 7. It is a refrigerant circuit for cooling operation in which the refrigerant circulates sequentially in an annular manner.

The refrigerant path switching means includes a first electromagnetic valve 31 that selectively switches to any one of the first to third refrigerant circulation paths, and a bypass pipe 34 that bypasses the indoor evaporator 6. .
Here, a third variable throttle means is installed between the discharge part of the electric compressor 3 and the inlet part of the indoor condenser 4 of the present embodiment.
The third variable throttle means is a third variable throttle means that can change the opening area of the throttle hole through which the refrigerant gas discharged from the discharge portion of the electric compressor 3 passes.
The third throttle 13 is installed upstream of the inlet portion of the indoor condenser 4 in the refrigerant flow direction, and the state of the refrigerant flowing into the indoor condenser 4 (particularly, the inlet refrigerant of the indoor condenser 4 is overheated). Degree: SH) is adjusted according to the throttle opening.
The third diaphragm 13 is configured to be driven by an electric actuator such as a servo motor that variably controls the opening area (throttle opening) of the third diaphragm hole.
In the electric actuator, the throttle opening of the third throttle 13 is fully closed (throttle opening = 0%), intermediate opening (0% <throttle opening <100%), and fully open (throttle opening = 100%). It is possible to adjust.

Here, each electric actuator that drives the first to third apertures 11 to 13, each electromagnetic actuator of the first and second electromagnetic valves 31, 32, actuator 17, actuators 23 and 24, blower motor 26, actuator 29, and inverter 30 Is configured to be energized and controlled by the air conditioning ECU 1.
The inlet circuit of the air conditioning ECU 1 includes an inside air temperature sensor, an outside air temperature sensor, a solar radiation sensor, an A / M opening sensor, a refrigerant pressure sensor 41, an outlet refrigerant temperature sensor 42, an evaporator temperature sensor 43, an inlet refrigerant temperature sensor 44, and the like. It is connected.
The inlet refrigerant temperature sensor 44 is compressor outlet refrigerant temperature detection means for detecting the temperature of the refrigerant that has flowed out from the discharge part (exit part) of the electric compressor 3.

The air conditioning ECU 1 calculates (determines) the superheat degree calculating means for calculating (determining) the superheat degree (current SH) of the inlet refrigerant of the indoor condenser 4 and the target superheat degree (target SH) of the inlet refrigerant of the indoor condenser 4. And a target superheat degree calculating means.
The current SH is the pressure of the refrigerant flowing out from the outlet of the indoor condenser 4 (detected value of the refrigerant pressure sensor 41) and the temperature of the refrigerant flowing into the inlet of the indoor condenser 4 (detection of the inlet refrigerant temperature sensor 44). Value). The current SH may be read from a map created by measuring these relationships in advance through experiments or the like.
The air conditioning ECU 1 has third throttle opening control means for reducing the throttle opening of the third throttle 13 in the B / L mode than in the FOOT mode.

[Control Method of Example 3]
Next, the control method of the refrigerating cycle of the present embodiment will be briefly described with reference to FIGS.

When the heating mode is selected as the operation mode, the control routine of FIG. 13 is started and the low temperature side (FACE) blowing temperature control is executed (discharge capacity control means: step S61).
Specifically, the rotational speed of the electric motor of the electric compressor 3 is adjusted so that the current indoor condenser temperature (calculated value based on the pressure sensor value: TAV) becomes the target indoor condenser temperature (TAO). . That is, the target rotational speed of the electric compressor 3 is determined.
The rotational speed of the electric compressor 3 (the discharge capacity of the refrigerant discharged from the electric compressor 3) may be read from a map created by measuring these relationships in advance through experiments or the like.
In this embodiment, it is read from a map (not shown) stored (stored) in the memory in advance.

Next, efficiency control is executed (first throttle opening control means: step S62).
Specifically, a target SC (target supercooling degree SC of the refrigerant at the outlet of the indoor condenser 4) is calculated (determined).
The target SC is based on an optimum efficiency map (see FIG. 14A) created by measuring the relationship with the indoor condenser load (for example, TE, TR, or TAM that is the suction temperature of the indoor condenser 4) in advance through experiments or the like. You may make it read.
In this embodiment, reading is performed from an optimum efficiency map (see FIG. 14A) stored (stored) in a memory in advance. In addition, when the indoor condenser load of Fig.14 (a) is made into the preset indoor condenser load (M value), the target SC becomes N value corresponding to M value.
Next, the throttle opening degree of the first throttle 11 is adjusted so that the current SC (the current degree of subcooling of the outlet refrigerant of the indoor condenser 4 is the calculated value) becomes the target SC. That is, the target first throttle opening degree of the first throttle 11 is determined.

Next, it is determined whether or not the air outlet mode is the B / L mode (step S63). If this determination is NO, the target third throttle opening is set to fully open. That is, the third throttle 13 is turned OFF and fully opened (third throttle opening control means: step S64). Thereafter, the control routine of FIG. 13 is exited.
Moreover, when the determination result of step S63 is YES, high temperature side (FOOT) blowing temperature control is executed (third throttle opening control means: step S65). Thereafter, the control routine of FIG. 13 is exited.
Specifically, the target SH (target superheat degree SH of the inlet refrigerant of the indoor condenser 4) is calculated.
The target SH may be read from an upper and lower temperature difference map (see FIG. 14B) created by measuring a relationship with the target upper and lower temperature difference in advance through experiments or the like.
In this embodiment, the temperature is read from an upper and lower temperature difference map (see FIG. 14B) stored (stored) in a memory in advance. When the target vertical temperature difference in FIG. 14B is a preset target vertical temperature difference (O value: 10 to 15 degrees, for example), the target SH is a P value corresponding to the O value.
Next, the throttle opening degree of the third throttle 13 is adjusted so that the current SH (current superheat degree SH of the refrigerant at the inlet of the indoor condenser 4: calculated value) becomes the target SC. That is, the target third throttle opening degree of the third throttle 13 is determined.

[Features of Example 3]
As described above, in the vehicle air conditioner of the third embodiment, the air passing through the SH region on the refrigerant inlet side of the indoor condenser 4 is blown out from the FOOT outlet through the FOOT opening 19 into the vehicle interior. The indoor condenser 4 is arranged in the air conditioning duct 2 so that air passing through the SC region on the refrigerant outlet side of the indoor condenser 4 is blown out from the FACE outlet through the FACE opening 18 into the vehicle interior.

At the time of heating operation in which the heating mode (first refrigerant circulation path) is selected as the operation mode, the FOOT mode or the B / L mode is selected as the outlet mode, and the first throttle 11 of the refrigeration cycle becomes the control opening, The second throttle 12 is fully closed and the first electromagnetic valve 31 is opened.
As a result, the high-temperature and high-pressure refrigerant gas discharged from the discharge portion of the electric compressor 3 is transferred to the third throttle 13 → the indoor condenser 4 → the first throttle 11 → the outdoor heat exchanger 5 → the first electromagnetic valve 31 → the accumulator 7. → The refrigerant circulates in the order of the electric compressor 3.
At this time, the opening degree of the A / M door 28 is 100% that fully opens the hot air passage that passes through the indoor condenser 4 and fully closes the bypass passage 27 that bypasses the indoor condenser 4. Thereby, the air that has passed through the indoor evaporator 6 is heated by the indoor condenser 4 to the high-temperature refrigerant gas discharged from the discharge portion of the electric compressor 3.
The heated air is blown into the vehicle interior from the FACE opening 18 and the FOOT opening 19 to heat the vehicle interior.

In the heating operation of the refrigerant flow as described above, when the outlet mode is the B / L mode, the target SH based on the required vertical temperature difference is set, and the current SH is set to the set target SH. The throttle opening degree of the three throttles 13 is adjusted.
When the outlet mode is the FOOT mode, the target SH that optimizes the cycle efficiency is determined, and the throttle opening of the third throttle 13 is adjusted so that the current SH becomes the set target SH.
As described above, the vehicle air conditioner according to the third embodiment has the same effects as the first and second embodiments.
Even in the dehumidifying and heating mode, the throttle opening of the third throttle 13 may be adjusted.

[Modification]
In the present embodiment, the present invention is applied to a vehicle air conditioner (automobile air conditioner for a vehicle) that air-conditions the interior of a vehicle such as an electric vehicle or a hybrid vehicle, but the present invention is an internal combustion engine (engine). The present invention may be applied to a vehicle air conditioner (automatic air conditioner for automobiles) that air-conditions the interior of a vehicle such as an automobile that travels using the power source.

In this embodiment, the indoor evaporator 6 is arranged so as to be orthogonal to the direction of airflow flowing through the air conditioning duct 2, but the room evaporation is performed so as to be parallel to the direction of airflow flowing through the air conditioning duct 2. A vessel 6 may be arranged.
In the present embodiment, the air upstream side surface of the indoor condenser 4 is opened and closed by the A / M door 28, but the air downstream side surface of the indoor condenser 4 may be opened and closed by the A / M door. Further, the air upstream side surface or the air downstream side surface of the indoor condenser 4 or the air upstream side surface and the air downstream side surface of the indoor condenser 4 may be opened and closed by a plurality of A / M doors.

In this embodiment, the rotational speed of the electric motor that rotationally drives the compressor is varied to control the discharge capacity of the refrigerant discharged from the compressor, but the compressor is rotationally driven by an internal combustion engine (engine), A capacity control valve capable of changing the discharge capacity of the refrigerant may be installed in the compressor, and the discharge capacity of the refrigerant discharged from the compressor may be controlled by controlling the valve opening degree of the capacity control valve.
In the first and second embodiments, from the viewpoint of using the temperature distribution of the air that has passed through the indoor condenser 4, the indoor refrigerant 4 is separated from the means for controlling the degree of supercooling (SC) of the outlet refrigerant of the indoor condenser 4. A means for controlling the degree of superheat of the inlet refrigerant of the condenser 4 may be employed.

  In this embodiment, a predetermined vertical temperature difference is created between the vehicle interior upper air outlet (FACE air outlet) and the vehicle interior lower air outlet (FOOT air outlet) to eliminate the feeling of hot flashing on the passenger's head, and Although it is configured to ensure a comfortable feeling in the feet of the passenger and to perform comfortable vehicle interior (dehumidification) heating due to cold head heat, the vehicle interior left outlet (passenger side FACE outlet or passenger side FOOT outlet) And a vehicle interior air conditioning (cooling, heating, dehumidifying heating) by creating a predetermined left-right temperature difference between the vehicle and the vehicle interior right side outlet (driver seat side FACE outlet or driver seat side FOOT outlet) May be. In addition, a vehicle interior front outlet (front seat side FACE outlet or front seat FOOT outlet) and a vehicle interior rear side (or intermediate side) outlet (rear seat FACE outlet or rear seat FOOT outlet) A predetermined front-rear temperature difference may be created between the two and the vehicle interior air conditioning (cooling, heating, dehumidifying heating) may be performed.

In the present embodiment, the A / M door opening is controlled so that the A / M door opening reaches the maximum heating state (MAXHOT) in which the indoor condenser 4 is fully opened during the heating operation or the dehumidifying heating operation. During the heating operation or the dehumidifying heating operation, the A / M door opening degree may be controlled so as to be in a heating state in which the bypass passage 27 is partially closed.
Further, the second throttle 12 of the second variable throttle means is configured by a valve hole through which the refrigerant passes, a valve body that changes an opening area (throttle opening) of the valve hole, an actuator that drives the valve body, and the like. The electric expansion valve may be replaced.

  In the present embodiment, during the heating operation or the dehumidifying heating operation, the A / M door opening is set to the MAXHOT position, and the first blowing (FOOT) for reducing the temperature difference between the air blown out from the plurality of outlets into the vehicle compartment. Executes throttle opening control to reduce the throttle opening of the variable throttle means in the second blowing (B / L) mode, which increases the temperature difference of the air blown into the vehicle interior from the plurality of outlets than in the mode. However, throttle opening control is performed to increase the throttle opening of the variable throttle means in the first blowing (FOOT) mode and to reduce the throttle opening of the variable throttle means in the second blowing (B / L) mode. May be executed.

  In the present embodiment, during the heating operation or the dehumidifying heating operation, the A / M door opening is set to the MAXHOT position, and the first blowing (FOOT) for reducing the temperature difference between the air blown out from the plurality of outlets into the vehicle compartment. The throttle opening of the third variable throttling means (the third throttling 13) in the second blowing (B / L) mode in which the temperature difference of the air blown out from the plurality of outlets into the vehicle compartment is larger than in the mode. In the first blowing (FOOT) mode, the throttle opening of the third variable throttle means is increased, and in the second blowing (B / L) mode, the third variable throttle is controlled. You may perform the throttle opening degree control which makes the throttle opening degree of a means small.

1 Air conditioning ECU (air conditioning control device)
2 Air conditioning duct 3 Electric compressor 4 Indoor condenser (Indoor heat exchanger for heating)
5 Outdoor heat exchanger (outdoor evaporator, outdoor condenser)
6 Indoor evaporator (cooling indoor heat exchanger)
7 Accumulator (gas-liquid separator)
11 First diaphragm (first decompression means, first variable diaphragm means)
12 Second diaphragm (second decompression means, second variable diaphragm means)
13 Third aperture (third variable aperture means)
18 FACE opening 19 FOOT opening 27 Bypass flow path 28 A / M door

Claims (13)

(A) A compressor that compresses and discharges the refrigerant and can change the discharge capacity of the refrigerant, a first indoor heat exchanger that condenses the refrigerant discharged from the compressor, and an outflow from the first indoor heat exchanger A refrigeration cycle in which the refrigerant circulates, having a decompression means for decompressing the refrigerant, an outdoor heat exchanger for evaporating the refrigerant decompressed by the decompression means, and a second indoor heat exchanger for evaporating the refrigerant decompressed by the decompression means When,
(B) an air conditioning duct having a plurality of air outlets for blowing air into the vehicle interior of the vehicle;
(C) an air mix door that adjusts the amount of air that passes through the first indoor heat exchanger and the amount of air that flows through a bypass flow path that bypasses the first indoor heat exchanger;
(D) In a vehicle air conditioner provided with a discharge capacity of refrigerant discharged from the compressor and an air conditioning control device that controls the opening degree of the air mix door,
The first indoor heat exchanger is installed in the air conditioning duct, and heats the air that has passed through the second indoor heat exchanger with the refrigerant during heating operation or dehumidifying heating operation to heat the refrigerant. Because
The second indoor heat exchanger is an indoor evaporator that is installed in the air conditioning duct and cools and dehumidifies the air flowing through the air conditioning duct by exchanging heat with a refrigerant during a dehumidifying heating operation.
The plurality of air outlets include a first air outlet that blows air that has passed through a superheat area on the refrigerant inlet side of the indoor condenser into the vehicle interior, and air that has passed through a subcool area on the refrigerant outlet side of the indoor condenser. A second outlet that blows into the passenger compartment,
The pressure reducing means is a variable throttle means for adjusting the state of the refrigerant that has passed through the indoor condenser according to the throttle opening degree,
The air conditioning control device increases the temperature difference of the air blown from the plurality of air outlets into the vehicle compartment as compared to the first blow mode in which the temperature difference of the air blown from the plurality of air outlets to the vehicle compartment is reduced. The vehicle air conditioner further comprises a throttle opening control means for reducing the throttle opening of the variable throttle means when in the mode. In the vehicle air conditioner according to claim 1,
The air conditioning control device is configured so that the air mix door opening degree is a maximum heating state in which the indoor condenser is fully opened or a heating state in which the bypass passage is partially closed during heating operation or dehumidifying heating operation. A vehicle air conditioner comprising door opening control means for controlling an air mix door opening. The vehicle air conditioner according to claim 1 or 2,
The air-conditioning control device discharges from the compressor based on the target temperature of the indoor evaporator during the heating operation or the dehumidifying heating operation during the heating operation or the dehumidifying heating operation and the target evaporator temperature calculating means for calculating the target temperature of the indoor evaporator. A vehicle air conditioner comprising discharge capacity control means for controlling the discharge capacity of the refrigerant. The vehicle air conditioner according to claim 1 or 2,
The air conditioning control device discharges from the compressor based on the target temperature of the indoor condenser during the heating operation or the dehumidifying heating operation, and the target condenser temperature calculating means for calculating the target temperature of the indoor condenser. A vehicle air conditioner comprising discharge capacity control means for controlling the discharge capacity of the refrigerant. In the vehicle air conditioner according to any one of claims 1 to 4,
The variable throttle means is installed on the upstream side in the refrigerant flow direction from the inlet of the outdoor heat exchanger, and the first variable throttle means installed on the upstream side in the refrigerant flow direction from the inlet of the indoor evaporator. A vehicle air conditioner comprising the second variable throttle means. In the vehicle air conditioner according to claim 5,
The refrigeration cycle includes a first refrigerant circulation path in which the compressor, the indoor condenser, the first variable throttle means, and the outdoor heat exchanger are sequentially connected in a pipe to circulate refrigerant.
The second refrigerant circulation in which the compressor, the indoor condenser, the first variable throttle means, the outdoor heat exchanger, the second variable throttle means, and the indoor evaporator are sequentially connected in a pipe to circulate the refrigerant. Route,
A vehicle air conditioner comprising path switching means for switching between the first refrigerant circulation path and the second refrigerant circulation path. The vehicle air conditioner according to claim 6,
The refrigeration cycle includes a first refrigerant circulation path in which the compressor, the indoor condenser, the first variable throttle means, and the outdoor heat exchanger are sequentially connected in a pipe to circulate refrigerant.
The compressor, the indoor condenser, the first variable throttle means, and the outdoor heat exchanger are sequentially connected in an annular manner to circulate refrigerant, and the compressor, the indoor condenser, and the second variable throttle. And a second refrigerant circulation path through which the refrigerant circulates in such a manner that the means and the indoor evaporator are sequentially connected in an annular pipe.
A vehicle air conditioner comprising path switching means for switching between the first refrigerant circulation path and the second refrigerant circulation path. In the vehicle air conditioner according to any one of claims 5 to 7,
The air conditioning control device has a condenser temperature detecting means for detecting a temperature of the indoor condenser, and a target condenser temperature calculating means for calculating a target temperature of the indoor condenser,
The throttle opening control means determines an opening ratio of the first and second variable throttle means so that a detection value of the condenser temperature detection means becomes a calculation value of the target condenser temperature calculation means. A vehicle air conditioner characterized by the above. In the vehicle air conditioner according to any one of claims 1 to 8,
The air conditioning control device has a supercooling degree calculating means for calculating a degree of supercooling of the outlet refrigerant of the indoor condenser, and a target supercooling degree calculating means for calculating a target supercooling degree of the outlet refrigerant of the indoor condenser. And
The throttle opening control means adjusts the throttle opening of the variable throttle means so that the calculated value of the supercooling degree calculating means becomes the calculated value of the target supercooling degree calculating means. Air conditioner. In the vehicle air conditioner according to any one of claims 1 to 9,
The vehicle air conditioner, wherein the refrigeration cycle has a third variable throttle means for adjusting the state of the inlet refrigerant of the indoor condenser according to the throttle opening. The vehicle air conditioner according to claim 10,
The refrigeration cycle includes a first refrigerant circulation in which the compressor, the third variable throttle means, the indoor condenser, the first variable throttle means, and the outdoor heat exchanger are sequentially connected in a pipe to circulate refrigerant. Route,
The compressor, the third variable throttle means, the indoor condenser, the first variable throttle means, the outdoor heat exchanger, the second variable throttle means, and the indoor evaporator are sequentially connected in an annular manner to form a refrigerant. A second refrigerant circulation path through which
A vehicle air conditioner comprising path switching means for switching between the first refrigerant circulation path and the second refrigerant circulation path. The vehicle air conditioner according to claim 10 or 11,
The air conditioning control device has third throttle opening control means for reducing the throttle opening of the third variable throttle means in the second blowing mode than in the first blowing mode. A vehicle air conditioner characterized by the above. The vehicle air conditioner according to claim 12,
The air conditioning control device
Superheat degree calculating means for calculating the degree of superheat of the refrigerant at the inlet of the indoor condenser;
And a target superheat degree calculating means for calculating a target superheat degree of the refrigerant at the inlet of the indoor condenser, wherein the third throttle opening degree control means has a calculated value of the superheat degree calculating means of the target superheat degree calculating means. An air conditioner for a vehicle, wherein the throttle opening of the third variable throttle means is adjusted so as to be a calculated value.

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