JP2006224705A - Air-conditioner for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce useless energy consumption and actuation noises in an air-conditioner for a vehicle. <P>SOLUTION: This automatic-control type air-conditioner for a vehicle automatically controls the temperature and the volume of air blown in a compartment. In this conditioner, it is judged that an air suction mode is an outside air mode (S40), and that a vehicle speed is not less than a predetermined value V1 (S50). When it is judged that an air-conditioning thermal load is not more than a predetermined volume (S60, S70), a compressor and a blower are stopped (S80, S90). <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a blower and compressor stop control in an automatic control type vehicle air conditioner.

  Conventionally, various automatic control type vehicle air conditioners have been proposed (see, for example, Patent Document 1). In this Patent Document 1, a target blown air temperature TAO for maintaining the passenger compartment temperature (inner air temperature) at the passenger's set temperature is calculated based on the passenger compartment temperature, the outside air temperature, the amount of solar radiation, the preset temperature, etc. The air mix door opening, the air volume of the blower (the air volume of the air blown into the passenger compartment), and the like are automatically controlled according to the target air temperature TAO.

Further, when the air conditioner switch that is a command switch for operating the compressor is turned on, the temperature of the evaporator that forms the cooling heat exchanger is calculated based on the target evaporator temperature TEO calculated based on the target blown air temperature TAO or the like. The compressor operation is automatically controlled so that Specifically, the compressor operation control is intermittent control of a fixed capacity compressor or capacity control of a variable capacity compressor.
Japanese Patent No. 3198573

  By the way, in the automatic control system as described above, even when the vehicle interior temperature and the outside air temperature are both substantially equal to the set temperature (when the air-conditioning heat load is small), the blower continues the air blowing operation, and the compressor Continues to operate so that the evaporator temperature reaches the target evaporator temperature TEO.

  However, if the vehicle interior temperature and the outside air temperature are both substantially equal to the set temperature, it is not necessary to operate the compressor for controlling the vehicle interior temperature. Also, if the air intake mode of the air conditioner is set to the outside air introduction mode and the vehicle is traveling at a vehicle speed above a certain value, the outside air is removed by the running dynamic pressure (ram pressure) of the vehicle. It can be introduced into the passenger compartment through the ventilation path.

  Therefore, when the vehicle interior temperature and the outside air temperature are both substantially equal to the set temperature, continuing the operation of the blower and the compressor consumes useless energy and generates operating noise of the blower and the compressor.

  The present invention has been made in view of the above points, and an object thereof is to reduce wasteful energy consumption and operating noise in a vehicle air conditioner.

In order to achieve the above object, according to the first aspect of the present invention, in the vehicle air conditioner of the automatic control system that automatically controls the temperature of the air blown into the vehicle interior and the air volume of the air blown into the vehicle interior,
When the air suction mode is the outside air mode and the vehicle speed is equal to or higher than a predetermined value, when it is determined that the air conditioning heat load is equal to or lower than the predetermined amount, the blower (8 ) Is stopped.

  According to this, even when the low heat load is judged and the blower (8) is stopped, the outside air can be introduced into the vehicle interior through the ventilation path of the air conditioner by the running dynamic pressure (ram pressure) of the vehicle. The passenger comfort can be maintained.

  Therefore, wasteful consumption of blower driving energy can be prevented while maintaining passenger comfort. Moreover, blower operating noise can be reduced.

In invention of Claim 2, in the vehicle air conditioner of Claim 1, in the cooling state of the heat exchanger (9) for cooling which cools the air which blows off into a vehicle interior, and the heat exchanger (9) for cooling A refrigeration cycle compressor (11) for producing
When the conditions for stopping the blower (8) are determined, the compressor (11) is also stopped.

  According to this, since both the blower (8) and the compressor (11) are stopped when it is determined that the heat load is low, it is possible to further improve the effect of preventing wasteful energy consumption and suppressing noise.

In invention of Claim 3, in the vehicle air conditioner of Claim 1 or 2, it has the temperature setting means (37) which sets the temperature of a vehicle interior,
When the temperature difference between the set temperature of the temperature setting means (37) and the outside air temperature and the temperature difference between the set temperature of the temperature setting means (37) and the vehicle interior temperature are within predetermined values, It is characterized by determining that it is below the fixed amount.

  According to this, the determination at the time of a low heat load can be accurately performed based on the temperature difference between the vehicle interior set temperature and the outside air temperature and the temperature difference between the vehicle interior set temperature and the vehicle interior temperature.

  In addition, the code | symbol in the bracket | parenthesis of each said means shows the correspondence with the specific means as described in embodiment mentioned later.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an outline of the overall configuration of the present embodiment. Since this overall configuration may be basically the same as that of Patent Document 1, it will be briefly described. The vehicle air conditioner includes an indoor air conditioning unit 1 that is disposed on the inside of an instrument panel at the forefront of the vehicle interior.

  This indoor air-conditioning unit 1 has a case 2 and constitutes an air passage through which air is blown toward the vehicle interior.

  An inside / outside air switching box 5 having an inside air introduction port 3 and an outside air introduction port 4 is arranged at the most upstream part of the air passage of the case 2. Inside / outside air switching box 5, an inside / outside air switching door 6 as inside / outside air switching means is rotatably arranged.

  The inside / outside air switching door 6 is driven by a servo motor 7, and an inside air mode for introducing inside air (vehicle compartment air) from the inside air introduction port 3 and an outside air mode for introducing outside air (vehicle compartment outside air) from the outside air introduction port 4. And switch.

  On the downstream side of the inside / outside air switching box 5, an electric blower 8 that generates an air flow toward the vehicle interior is disposed. The blower 8 is configured to drive a centrifugal blower fan 8a by a motor 8b. An evaporator 9 that cools the air flowing in the case 2 is disposed on the downstream side of the blower 8.

  The evaporator 9 is a cooling heat exchanger that cools the air blown from the blower 8 and is one of the elements constituting the refrigeration cycle apparatus 10. Note that the refrigeration cycle apparatus 10 is well-known, so that the refrigerant circulates from the discharge side of the compressor 11 to the evaporator 9 through the condenser 12, the liquid receiver 13, and the expansion valve 14 serving as a pressure reducing means. It is configured. Outdoor air (cooling air) is blown to the condenser 12 by an electric cooling fan 12a.

  In the refrigeration cycle apparatus 10, the compressor 11 is driven by a vehicle engine (not shown) via an electromagnetic clutch 11a. Therefore, the operation of the compressor 11 can be intermittently controlled by the energization of the electromagnetic clutch 11a. The compressor 11 of the present embodiment is a fixed capacity compressor that always operates with a constant discharge capacity.

  The evaporator 9 cools the blown air by the low-temperature and low-pressure gas-liquid two-phase refrigerant that has been decompressed by the expansion valve 14 absorbs heat from the blown air of the blower 8 and evaporates.

On the other hand, in the indoor air conditioning unit 1, a heater core 15 that heats the air flowing in the case 2 is disposed on the downstream side of the evaporator 9. The heater core 15 is a heating heat exchanger that heats the air (cold air) that has passed through the evaporator 9 using warm water (engine cooling water) of the vehicle engine as a heat source. A bypass passage 16 is formed on the side of the heater core 15.
The bypass air of the heater core 15 flows.

Between the evaporator 9 and the heater core 15, an air mix door 17 serving as a temperature adjusting means is rotatably arranged. The air mix door 17 is driven by a servo motor 18 so that its rotational position (opening) can be continuously adjusted.

The ratio of the amount of air passing through the heater core 15 (warm air amount) and the amount of air passing through the bypass passage 16 and bypassing the heater core 15 (cold air amount) is adjusted by the opening degree of the air mix door 17. The temperature of the air blown into the room is adjusted.

At the most downstream part of the air passage of the case 2, a defroster outlet 19 for blowing out the conditioned air toward the front window glass W of the vehicle, a face outlet 20 for blowing out the conditioned air toward the face of the occupant, A total of three types of air outlets 21 are provided, which are foot outlets 21 for blowing air-conditioned air toward the feet of passengers.

A defroster door 22, a face door 23, and a foot door 24 are rotatably disposed upstream of the air outlets 19 to 21. The doors 22 to 24 are opened and closed by a common servo motor 25 via a link mechanism (not shown).

Next, the outline of the electric control unit of this embodiment will be described.
It is composed of a known microcomputer including OM and RAM and its peripheral circuits.
The air conditioning control device 30 stores a control program for air conditioning control in its ROM, and performs various calculations and processes based on the control program.

  Sensor detection signals are input from the sensor groups 31 to 35, 43 to the input side of the air conditioning control device 30, and various operation signals are received from the air conditioning panel 36 disposed in the vicinity of an instrument panel (not shown) at the front of the passenger compartment. Is entered.

As the sensor group, specifically, an outside air sensor 3 that detects an outside air temperature (a vehicle compartment outside temperature) Tam.
1. Inside air sensor 32 for detecting inside air temperature (in-vehicle temperature) Tr, amount of solar radiation Ts incident on the inside of the vehicle
The solar radiation sensor 33 for detecting the temperature of the evaporator 9 and the evaporator 9 air blowing temperature Te
Are provided, an evaporator temperature sensor 34 for detecting the temperature, a water temperature sensor 35 for detecting the temperature Tw of hot water (engine cooling water) flowing into the heater core 15, a vehicle speed sensor 43 for detecting the vehicle speed Vs, and the like.

  Further, the air conditioning panel 36 has various operation switches, such as a temperature setting switch 37 serving as a temperature setting means for setting the vehicle interior temperature, a blowing mode switch 38 for manually setting a blowing mode switched by the blowing mode doors 22 to 24, and an inside / outside air switching. An inside / outside air changeover switch 39 for manually setting the inside air mode and the outside air mode by the door 6, an air conditioner switch 40 for issuing an operation command signal for the compressor 11 (ON signal of the electromagnetic clutch 11a), and a fan operation for manually setting the air volume switching of the blower 8. A switch 41, an auto switch 42 for outputting a command signal for the air conditioning automatic control state, and the like are provided.

On the output side of the air-conditioning control device 30, there are an electromagnetic clutch 11 a of the compressor 11, servomotors 7, 18, 25 serving as electric drive means for each device, a motor 8 b of the blower 8, and a condenser cooling fan 12.
The motor 12b of a is connected, and the operation of these devices is controlled by the output signal of the air conditioning control device 30.

Next, the operation of this embodiment in the above configuration will be described. First, the outline of the operation of the indoor air conditioning unit 1 will be described. By operating the blower 8, the air introduced from the inside air introduction port 3 or the outside air introduction port 4 is blown through the case 2 toward the vehicle interior. . Also, the refrigerant is circulated in the refrigeration cycle apparatus 10 by energizing the electromagnetic clutch 11a to bring the electromagnetic clutch 11a into a connected state and driving the compressor 11 with a vehicle engine.

The blown air from the blower 8 first passes through the evaporator 9 to be cooled and dehumidified, and this cold air then flows through the heater core 15 and the bypass passage 16 according to the rotational position (opening) of the air mix door 17. It is divided into the flow that passes. The flow passing through the heater core 15 is heated to become hot air, and the flow passing through the bypass passage 16 remains cold air.

Therefore, the ratio of the amount of air passing through the heater core 15 (warm air amount) and the amount of air passing through the bypass passage 16 (cold air amount) is adjusted by the opening degree of the air mix door 17, and thereby the air blown into the vehicle interior The temperature can be adjusted. And this temperature-controlled conditioned air is supplied from any one or more of the defroster air outlet 19, the face air outlet 20 and the foot air outlet 21 located at the most downstream part of the air passage of the case 2. It blows out into the passenger compartment and performs air conditioning in the passenger compartment and fogging prevention of the front window glass W of the vehicle.

Next, the air conditioning automatic control according to the present embodiment will be described with reference to FIG. FIG. 2 is a flowchart of a control routine executed by the microcomputer of the air-conditioning control device 30. This control routine starts when the auto switch 42 is turned on in an on state of an ignition switch of a vehicle engine (not shown).

  First, the vehicle interior set temperature Tset set by the temperature setting switch 37 of the air conditioning panel 36 is read (S10). Next, various detection data (sensor detection signals) detected by the sensor groups 31 to 35 and 43 are read (S20).

  Next, the target blowing temperature TAO of the blowing air into the passenger compartment is calculated (S30). This target blowout temperature TAO is a vehicle compartment blowout air temperature necessary for maintaining the vehicle compartment temperature (inside air temperature) Tr at the set temperature Tset set by the temperature setting switch 37 regardless of the air conditioning thermal load fluctuation. This TAO is calculated by the following equation (1) based on the set temperature Tset, the outside air temperature Tam, the inside air temperature Tr, and the solar radiation amount Ts.

TAO = Kset × Tset−Kr × Tr−Kam × Tam−Ks × Ts + C (1)
Where Kset, Kr, Kam, Ks: Control gain
C: Correction Constant Next, it is determined whether the air suction mode by the inside / outside air switching door 6 is the outside air mode (S40). If the outside air mode is the outside air mode, the vehicle speed Vs detected by the vehicle speed sensor 43 is a predetermined value V1. It is determined whether this is the case (S50).

   When the vehicle speed Vs is equal to or higher than the predetermined value V1, it is determined whether the absolute value of the temperature difference between the outside air temperature Tam and the vehicle interior set temperature Tset is within a predetermined minute value T1 (S60). Then, it is next determined whether or not the absolute value of the temperature difference between the vehicle interior temperature Tr and the vehicle interior set temperature Tset is within a predetermined minute value T2 (S70). Here, the predetermined minute values T1 and T2 may be the same value or may be slightly deviated from each other.

  If the determination in S70 is YES, an OFF (stop) signal is then output to the electromagnetic clutch 11a of the compressor 11 and the drive motor 8b of the blower 8 to stop the compressor 11 and the blower 8 (S80, S90).

  Next, the opening degree of the air mix door 17 is controlled to adjust the temperature of the air blown into the passenger compartment (S100). Specifically, the target opening degree SW of the air mix door 17 is set to the target blowing temperature TAO, the evaporator blowing air temperature Te detected by the evaporator temperature sensor 34, and the hot water temperature Tw detected by the water temperature sensor 35. Based on the above, the following equation (2) is used.

SW = {(TAO−Te) / (Tw−Te)} × 100 (%) (2)
Then, the air mix door 17 is driven and controlled by the servo motor 18 so that the actual opening degree of the air mix door 17 becomes the target opening degree SW. Thus, the vehicle interior air temperature is controlled to become the target air temperature TAO, and the vehicle interior temperature Tr is maintained at the set temperature Tset.

  SW = 0 (%) is the maximum cooling position of the air mix door 17, and the bypass passage 16 is fully opened and the ventilation path on the heater core 15 side is fully closed. On the other hand, SW = 100 (%) is the maximum heating position of the air mix door 17 and fully closes the bypass passage 16 and fully opens the ventilation path on the heater core 15 side.

  By the way, even if the blower 8 is stopped, since the air suction mode by the inside / outside air switching door 6 is the outside air mode and the vehicle speed Vs is equal to or higher than the predetermined value V1, the running dynamic pressure (ram pressure) of the vehicle is used. Thus, the outside air can be blown out through the air passage inside the case 2 of the indoor air conditioning unit 1 into the vehicle interior.

  Also in this case, the outdoor air whose temperature is adjusted by the opening degree of the air mix door 17 can be blown out into the vehicle interior. In addition, since the temperature difference between the outside air temperature Tam and the vehicle interior set temperature Tset and the temperature difference between the vehicle interior temperature Tr and the vehicle interior set temperature Tset are both within predetermined minute values T1 and T2, the heat load of the air conditioning in the vehicle interior Is in a very small state. For this reason, even if the vehicle interior is air-conditioned only with the outside air wind caused by the running dynamic pressure (ram pressure), the air-conditioning feeling is not deteriorated.

  And by stopping the compressor 11 and the air blower 8, useless energy consumption can be reduced and the operation noise of the compressor 11 and the air blower 8 can be reduced.

  On the other hand, when the determinations in steps S40 to S70 are NO, the process proceeds to step S110, and the compressor 11 and the blower 8 are controlled by normal control.

  Since this normal control is a well-known control, in brief, first, the target evaporator outlet temperature TEO is calculated. Here, the target evaporator outlet temperature TEO is mainly determined for controlling the temperature of the air blown into the passenger compartment, the anti-fogging control of the vehicle front window glass W, the power saving (economy) control of the compressor 11, and the like. It is a value and is calculated according to the target blowing temperature TAO, the outside air temperature Tam in step S30, and the like.

  The compressor 11 is controlled to operate so that the actual evaporator air temperature (detected temperature of the evaporator temperature sensor 34) Te becomes the target evaporator air temperature TEO. Specifically, when using a fixed capacity type compressor that always operates with a constant discharge capacity as the compressor 11, the energization of the electromagnetic clutch 11a is intermittently controlled to interrupt the operation of the compressor 11, thereby The operating rate of the compressor 11 is controlled.

  Further, the blower 8 automatically controls the applied voltage of the drive motor 8b so that the air volume changes according to the target blowing temperature TAO. Specifically, the voltage applied to the drive motor 8b of the blower 8 is maximized in the extremely low temperature range (maximum cooling range) and the extremely high temperature range (maximum heating range) of the target blowing temperature TAO, and the air volume of the blower 8 is set to the maximum air volume. Control to (Hi).

  When the cooling load decreases from the maximum cooling state and the target blowing temperature TAO increases from the extremely low temperature range toward the intermediate temperature range, the blower motor applied voltage is decreased in accordance with the increase in TAO, and the air volume of the blower 8 is increased. Decrease. Further, when the heating load decreases from the maximum heating state and the target blowing temperature TAO decreases from the extremely high temperature range toward the intermediate temperature range, the blower motor applied voltage is decreased according to the decrease in TAO, and the air volume of the blower 8 is decreased. Decrease. When TAO enters a predetermined intermediate temperature range, the blower motor applied voltage is set to the minimum value, and the air volume of the blower 8 is set to the minimum value.

(Other embodiments)
The present invention is not limited to the above-described embodiment, and can be variously modified as exemplified below.

  (1) In the above-described embodiment, the operation of the blower 8 and the compressor 11 is automatically stopped when the heat load of the air conditioning is small. However, in a high latitude area, a cool climate is obtained even in summer, and the cooling function is unnecessary. Become. Therefore, such a vehicle air conditioner for high latitude areas does not require the refrigeration cycle apparatus 10 including the evaporator 9 as a cooling heat exchanger. Therefore, in a vehicle air conditioner that does not include such a refrigeration cycle apparatus 10, only the blower 8 may be controlled to automatically stop when the heat load of the air conditioning is small.

  (2) In the above-described embodiment, the temperature difference between the set temperature Tset of the temperature setting switch 37 and the outside air temperature Tam, and the temperature difference between the set temperature Tset of the temperature setting switch 37 and the vehicle interior temperature Tr are both within a predetermined value. If it is determined that the air conditioning thermal load is equal to or less than the predetermined amount, the target blowing temperature TAO is an information value representing the magnitude of the air conditioning thermal load, and is an intermediate temperature range of the target blowing temperature TAO. Since the (predetermined temperature range near 25 ° C.) indicates the state where the air conditioning heat load is the smallest, it is determined that the target blowing temperature TAO is in the intermediate temperature range, and the air conditioning heat load is determined to be equal to or less than the predetermined amount. Also good.

  (3) In the above-described embodiment, the case where a fixed displacement compressor that always operates at a constant discharge capacity is used as the compressor 11 of the refrigeration cycle apparatus 10 has been described. However, the discharge capacity can be adjusted as the compressor 11. You may use a variable capacity type compressor and the electric compressor which can adjust rotation speed.

  (4) In the above-described embodiment, the air mix door 17 is used as the temperature adjusting means for the air blown into the passenger compartment. However, as this temperature adjusting means, a well-known method for adjusting the flow rate and temperature of hot water flowing into the heater core 15 is used. A hot water valve may be used.

1 is an overall system configuration diagram showing an embodiment of the present invention. It is a flowchart which shows the outline | summary of the air-conditioning control of one Embodiment of this invention.

Explanation of symbols

2 ... Case, 8 ... Blower, 9 ... Evaporator (cooling heat exchanger), 11 ... Compressor,
17 ... Air mix door (temperature adjusting means), 30 ... Air conditioning control device.

Claims (3)

In a vehicle air conditioner of an automatic control system that automatically controls the temperature of air blown into the passenger compartment and the air volume of air blown into the passenger compartment,
When the air suction mode is the outside air mode and the vehicle speed is equal to or higher than a predetermined value, when it is determined that the air conditioning heat load is equal to or lower than the predetermined amount, the blower (8 A vehicle air conditioner. A cooling heat exchanger (9) for cooling the air blown into the passenger compartment;
A refrigeration cycle compressor (11) for creating a cooling state of the cooling heat exchanger (9),
The vehicle air conditioner according to claim 1, wherein when the condition for stopping the blower (8) is determined, the compressor (11) is also stopped. Temperature setting means (37) for setting the temperature in the passenger compartment;
When the temperature difference between the set temperature of the temperature setting means (37) and the outside air temperature, and the temperature difference between the set temperature of the temperature setting means (37) and the vehicle interior temperature are within predetermined values, The vehicle air conditioner according to claim 1, wherein it is determined that the load is equal to or less than a predetermined amount.

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