JP2007099072A - Air-conditioner for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent an evaporator from overcooling to eliminate the risk of a compressor being over the capacity when the compressor is started and to preclude generation of a freezing odor. <P>SOLUTION: With ignition turned on, an air-conditioning control device calculates repetitively the target control value Duty 1(n) of the compressor through PI computation complying with the temperature deviation En of the evaporator blowout air temperature Te from the target cooling temperature TEO. Blower of the air-conditioning unit continues in the stopped condition while the engine cooling water temperature Tw remains low. When Tw rises to exceeds the threshold, the blower is turned into the blowing condition, and complying therewith the compressor is started. The Duty at this time is not Duty 1(n) computed repetitively, but substituted with a fixed value α set to a lower value than Duty 1(n), and the compressor is started with α. This suppresses the discharge capacity at the time of starting, and the evaporator is prevented from overcooling. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a vehicle air conditioner.

  Conventionally, the capacity control of a variable capacity compressor is controlled by a control value (duty value as a target value) output from the control means, the voltage applied to the electromagnetic mechanism of the capacity control valve that changes the discharge capacity of the compressor. It is to be done by.

  As a calculation method of the output control value of the control means, the air temperature in the downstream of the evaporator is sensed so that the detected air temperature in the downstream of the evaporator approaches the target temperature, that is, the detected temperature and the target Feedback calculation is performed by proportional integral (PI) calculation based on deviation from temperature.

  On the other hand, in the control of auto air conditioners, the air blower in the air conditioning unit is stopped to improve the air conditioning feeling in winter and low water temperature conditions, but the control means is always controlled with the ignition turned on. The value Duty is calculated. At this time, the evaporator downstream temperature rises due to radiation from the heater core as the temperature of the engine cooling water flowing through the heater core rises.

  In the control of the automatic air conditioner, the blower starts to operate in response to the rise in the water temperature, and the compressor is also started in response to this. The duty value, which is the target value of the compressor that is constantly calculated, has a large deviation between the detected temperature and the target temperature due to the rise in the temperature after the evaporator while the blower is stopped. Therefore, it is calculated as a maximum value or a large value close to the maximum value.

  Thus, when starting the operation of the blower accompanying the rise in water temperature, if the compressor is started with a large capacity, the evaporator will be supercooled due to excessive capacity, and as a result, the evaporator will freeze. Become. As a result of this freezing, the odorous component dissolved in the water distributed around the evaporator is released from the ice by freezing and mixed into the air, thereby generating a frozen odor.

  In view of the above points, an object of the present invention is to prevent overcooling of an evaporator and prevent generation of a frozen odor by preventing excessive capacity at the start of starting a compressor.

  In order to achieve the above object, the present invention is based on the target value (Duty) calculated based on the deviation (En) between the temperature (Te) of the evaporator (9) and the target cooling temperature (TEO) of the evaporator. In the vehicle air conditioner in which the compressor (11) is controlled by the discharge capacity, the target value is calculated when the blower (8) is switched from the stop state to the blower state by the calculation of the target value by the calculation means (S9). The first feature is that the value is replaced with a predetermined value (α, β, γ, λ) set lower than the value calculated up to the above.

  According to this invention, since the discharge capacity at the time of operation of the compressor can be suppressed to a value lower than the continuously calculated target value when the blower switches from the stopped state to the blower state, it is continuously calculated. Even if the evaporator is in a supercooled state when the compressor is operated at the target value, it is possible to operate the Cooling can be prevented and generation of a frozen odor due to freezing of the evaporator can be prevented.

  When the blower is in a stopped state, the temperature of the evaporator rises as the vehicle engine coolant temperature rises, so that the target value continuously calculated according to this rises to a relatively high value. . Therefore, the predetermined values (α, β, γ, λ) can be set as values lower than the target value.

  The predetermined value replaced at the time of switching of the operating state of the blower can be corrected according to the heat load state of the evaporator. Specifically, it correct | amends so that predetermined value may become low, so that the thermal load of an evaporator becomes low. More specifically, the predetermined value (β) is corrected by the outside air temperature (Tam), the predetermined value (γ) is corrected by the temperature (Te) on the air blowing side of the evaporator, or the inside / outside air The predetermined value (λ) may be corrected by the inlet state (TPI) of the inlet, the vehicle speed (SPD), and the outside air temperature (Tam).

  The present invention also provides a compressor with a discharge capacity corresponding to a target value (Duty) calculated based on a deviation (En) between the temperature (Te) of the evaporator (9) and the target cooling temperature (TEO) of the evaporator. In the vehicle air conditioner in which (11) is controlled, when the blower (8) is in a stopped state in the calculation of the target value by the calculation means (S9), the target value is set to a predetermined value (α, Duty1 (n−1). )), And the target value is calculated based on the fixed value when the blower switches from the stopped state to the blower state.

  According to this, when the blower (8) is in a stopped state, the control target value (Duty) of the compressor (11) is fixed to a predetermined value (α, Duty1 (n−1)), and the blower ( Since the target value is calculated based on the fixed value (α, Duty 1 (n−1)) and the deviation (En) when 8) switches to the blowing state, the compressor (11) is fixed at the time of switching. The target value calculated based on the determined predetermined value is operated, and the subsequent target value is calculated based on the fixed predetermined value, the deviation (En), and the change. That is, the discharge capacity of the compressor after the switching time of the operating state of the blower can be suppressed. Therefore, overcooling of the evaporator at the time of switching can be prevented, and generation of a frozen odor due to freezing of the evaporator can be prevented.

  The fixed predetermined value (Duty1 (n-1)) is used as the detected temperature (34) of the evaporator temperature detecting means (34) detected when the power-on switch (IG) to the calculating means is activated. If the correction is performed by Te), the value can be set according to the temperature change of the evaporator when the blower is stopped.

  In addition, the code | symbol in the bracket | parenthesis of each means described in a claim and this column shows the correspondence with the specific means as described in embodiment mentioned later.

(First embodiment)
Hereinafter, a first 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, and a vehicle air conditioner includes an indoor air conditioning unit 1 disposed on the inside of an instrument panel (instrument panel) at the forefront of a vehicle interior.

  This indoor air-conditioning unit 1 has a case 2 and constitutes an air passage 2a 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 portion of the air passage 2 a in the case 2. An inside / outside air switching door 6 is rotatably arranged in the inside / outside air switching box 5.

  The inside / outside air switching door 6 is driven by a servo motor 7, and the opening areas of the inside air introduction port 3 and the outside air introduction port 4 are continuously set in accordance with the suction opening degree TPI which is the opening degree of the inside / outside air switching door 6. Adjust to. When the inside / outside air switching door 6 has a suction opening TPI = 0%, the inside air introduction port 3 is fully opened and the outside air introduction port 4 is fully closed, so that only inside air (vehicle interior air) is introduced from the inside air introduction port 3. You can set the whole inside air (REC) mode.

  On the other hand, when the inside / outside air switching door 6 has a suction opening TPI = 100%, the inside air introduction port 3 is fully closed and the outside air introduction port 4 is fully opened. The full outside air (FRS) mode can be set. Further, by continuously adjusting the suction port opening TPI, which is the opening ratio of the inside air introduction port 3 and the outside air introduction port 4, between the all inside air mode and the all outside air mode, the introduction ratio of the inside air and the outside air is continuously maintained. The inside / outside air mixing mode can be set. The inside / outside air switching door 6 and the servo motor 7 constitute the inside / outside air switching means of this embodiment.

  In the downstream passage of the inside / outside air switching box 5, an electric blower 8 that blows air 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 serving as a cooling heat exchanger for cooling the blown air is disposed in the downstream passage of the blower 8.

  The evaporator 9 is one of the elements constituting the refrigeration cycle apparatus 10. The low-pressure refrigerant that has flowed into the evaporator 9 absorbs heat from the blown air blown by the blower 8 and evaporates, thereby cooling the blown air. The refrigeration cycle apparatus 10 is a well-known device, and includes an evaporator 9, a compressor 11, a condenser 12, a gas-liquid separator (receiver) 13, and an expansion valve 14.

  The compressor 11 sucks, compresses and discharges the refrigerant, and is rotationally driven by the rotational power of the vehicle engine E transmitted through the pulley 11a and the belt V. The compressor 11 is a variable capacity compressor, the details of which will be described later.

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

  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 degree) 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 conditioned air toward the front window glass W of the vehicle, a face outlet 20 for blowing 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 arranged at the upstream portions of these 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 compressor 11 will be described. The compressor 11 of the present embodiment is a variable capacity compressor that can continuously variably control the discharge capacity by an external control signal. Specifically, in the swash plate type compressor, the pressure of the swash plate chamber is controlled by using the discharge pressure and the suction pressure, thereby changing the inclination angle of the swash plate and changing the stroke of the piston. The machine discharge capacity can be continuously changed in the range of approximately 0% to 100%.

  Such a swash plate type variable displacement compressor 11 is well known. In the present embodiment, among the swash plate type variable displacement compressors, a flow control type variable displacement compressor known from Japanese Patent Application Laid-Open No. 2001-107854 is used as the compressor 11.

  The outline of the flow control type variable displacement compressor 11 will be described. The compressor 11 includes a displacement control valve 11b. The capacity control valve 11b includes a differential pressure responsive mechanism (not shown) that generates a force F1 due to a differential pressure ΔP corresponding to the discharge refrigerant flow rate of the compressor 11, and a force F1 due to a differential pressure corresponding to the discharge refrigerant flow rate. It incorporates an electromagnetic mechanism (not shown) that generates an opposing electromagnetic force F2. The electromagnetic force F2 of the electromagnetic mechanism is determined by a control current In output from an air conditioning control device 30 described later.

  The pressure in the swash plate chamber (not shown) of the compressor 11, that is, the control pressure Pc is changed by a valve body (not shown) that is displaced according to the force F 1 and the electromagnetic force F 2 corresponding to the differential pressure ΔP. Thus, the inclination angle of the swash plate is changed, whereby the discharge capacity is continuously changed. Here, the discharge capacity is the geometric volume of the working space where the refrigerant is sucked and compressed, and specifically, the cylinder volume between the top dead center and the bottom dead center of the piston stroke.

  In the swash plate type variable displacement compressor 11, as is well known, the control pressure Pc decreases, the swash plate tilt angle increases, the piston stroke increases, the discharge capacity increases, and conversely the control pressure Pc increases. The discharge capacity changing mechanism is configured so that the inclination angle of the swash plate decreases, the piston stroke decreases, and the discharge capacity decreases.

  By the way, since the electromagnetic force F2 is a force that opposes the force F1 corresponding to the differential pressure ΔP, the target differential pressure is determined by increasing / decreasing the electromagnetic force F2, and the actual differential pressure ΔP becomes the electromagnetic pressure. The control pressure Pc in the swash plate chamber is controlled so that the target differential pressure determined by the force F2 is reached, and the discharge capacity changes. Furthermore, since the differential pressure ΔP and the discharge refrigerant flow rate are in a proportional relationship, determining the target differential pressure determines the target discharge refrigerant flow rate.

  Since the electromagnetic force F2 is determined according to the control current In supplied to the electromagnetic mechanism of the capacity control valve 11b, as shown in FIG. 2, the target differential pressure and the target discharge refrigerant are increased according to the increase of the control current In. The flow rate increases.

  Specifically, the control current In is changed by duty control based on the output duty value calculated by proportional integral (PI) calculation, as is normally used in the configuration of the current control circuit. The output duty value and the target value based on the output duty value are calculated by the air-conditioning control device 30 as a calculation unit, and the calculation method thereof will be described later.

  Further, in the swash plate variable displacement compressor 11, the discharge capacity can be continuously changed from 100% to approximately 0% by adjusting the control pressure Pc. And the compressor 11 can be made into an operation stop state substantially by reducing discharge capacity to about 0% vicinity. Therefore, it is possible to adopt a clutchless configuration in which the rotation shaft of the compressor 11 is always connected to the pulley on the vehicle engine E side via the pulley 11a, a belt, and the like. Of course, an electromagnetic clutch may be attached to the rotating shaft of the compressor 11 as necessary, and power transmission to the compressor 11 may be intermittently performed by the electromagnetic clutch.

  Next, the outline of the electric control unit of the present embodiment will be described. The air conditioning control device (A / C ECU) 30 includes a known microcomputer including a CPU, a ROM, a RAM, and the like, and peripheral circuits thereof.

  When the ignition switch for starting and stopping the engine is turned on (IG is turned on), the air conditioning control device 30 performs arithmetic processing when DC power is supplied from a battery (not shown) that is an in-vehicle power source mounted on the vehicle. And is configured to start control processing. That is, in the present embodiment, the ignition switch corresponds to the power-on switch of the air conditioning control device 30 as the calculation means.

  Sensor detection signals are respectively input from the air conditioning sensor groups 31 to 36 to the input side of the air conditioning control device 30, and various air conditioning operations provided on the air conditioning operation panel 37 disposed near the instrument panel in the front part of the vehicle interior. Operation signals are input from the switches 38 to 43, respectively.

  Specifically, as the air conditioning sensor group, an outside air temperature sensor 31 as an outside air temperature detecting means for detecting the outside air temperature Tam, an inside air temperature sensor 32 for detecting the inside air temperature Tr, and the amount of solar radiation Ts incident on the vehicle interior are detected. A solar radiation sensor 33 that is disposed, an evaporator temperature sensor 34 that is disposed in an air blowing portion of the evaporator 9 and detects an evaporator blowing air temperature Te, and an engine cooling water temperature Tw that flows into the heater core 15. A water temperature sensor 35 for detecting the vehicle speed, a vehicle speed sensor 36 for detecting the vehicle speed SPD, and the like are provided.

  The air-conditioning operation panel 37 has various air-conditioning operation switches, such as a blow mode switch 38 for manually setting the blow mode switched by the blow mode doors 22 to 24, and an internal / external air switch for manually setting the internal / external air suction mode by the internal / external air switching door 6. A switch 39, an air conditioner switch 40 for outputting an operation command signal for the compressor 11, a blower operation switch 41 for manually setting the air volume of the blower 8, an auto switch 42 for outputting a command signal for an air conditioning automatic control state, and a temperature for setting a vehicle interior temperature A temperature setting switch 43 or the like serving as setting means is provided.

  The air conditioner switch 40 switches between the operating state and the stopped state of the compressor 11. When the air conditioner switch 40 is stopped, the control current In of the capacity control valve 11b is forcibly set to 0, and the compressor 11 The discharge capacity of the compressor 11 is substantially 0, and the compressor 11 is substantially stopped.

  On the other hand, when the air conditioner switch 40 is in an operating state, a control current In based on a predetermined output duty value (0 to 100%) calculated by the air conditioning control device 30 is output to the capacity control valve 11b, and the compressor 11 Is operated at a discharge capacity (0 to 100%) corresponding to the control current In. Even in this operating state, if the control current In, that is, the output duty value is set to 0%, the discharge capacity of the compressor 11 is also adjusted to 0% accordingly.

  On the output side of the air-conditioning control device 30, there are an electromagnetic capacity control valve 11b of the compressor 11, servo motors 7, 18, and 25 serving as electric drive means for each device, a motor 8b of the blower 8, and a condenser cooling fan 12a. The motor 12 b 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, an outline of the entire control process executed by the air conditioning control device 30 will be described based on a flowchart showing a main routine of FIG. This control process is performed when the auto switch 42 is turned on to set the auto mode, and when the compressor 11 is set to the operating state by the setting of the air conditioner switch 40, and the ignition of the engine as a power-on switch. The process starts when a switch (IG, not shown) is turned on, and is repeatedly executed at a predetermined repetition time (for example, 200 to 300 ms).

  First, in step S1, flags and timers are initialized, and in the next step S2, sensor detection signals from the air conditioning sensor groups 31 to 36 and operation signals of the air conditioning operation panel 37 are read.

  Next, the target blowing temperature TAO of the vehicle compartment blowing air is calculated in step S3. 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 43 regardless of the air conditioning thermal load fluctuation. Specifically, TAO is calculated by the following formula (1).

TAO = Kset * Tset-Kr * Tr-Kam * Tam-Ks * Ts + C
... (1)
Here, Tr is the inside air temperature detected by the inside air temperature sensor 32, Tam is the outside air temperature detected by the outside air temperature sensor 31, Ts is the amount of solar radiation detected by the solar radiation sensor 33, and Kset, Kr, Kam, and Ks are controlled. Gain and C are correction constants.

  Next, in step S4, the air volume of the air blown by the blower 8 is calculated. Specifically, the blower motor voltage applied to the motor 8b is calculated based on TAO. In the present embodiment, the blower motor voltage is set to the maximum value or a high voltage near the maximum value in the extremely low temperature range (maximum cooling range) and extremely high temperature range (maximum heating range) of TAO, and the air volume of the blower 8 is set to the maximum air volume or the maximum air volume. Control nearby. Then, as the TAO changes from the extremely low temperature region or the extremely high temperature region toward the intermediate temperature region, the blower motor voltage is decreased and the air volume of the blower 8 is decreased.

  When the engine coolant temperature Tw immediately after engine startup is low under heating conditions such as in winter, when the blower motor voltage = 0 and the blower 8 is stopped and the coolant temperature rises to such an extent that a passenger can feel the heating, Blowing is started, that is, warm-up control is performed.

  Next, in step S5, the target opening degree SW of the air mix door 17 is set to the TAO, the evaporator blown air temperature Te (detected temperature of the evaporator temperature sensor 34), and the engine coolant temperature Tw (detected by the water temperature sensor 35). Based on (temperature), it calculates by the following numerical formula (2).

SW = [(TAO−Te) / (Tw−Te)] × 100 (%) (2)
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.

  Next, the blowing mode is determined in step S6. This blowing mode is also determined based on the target blowing temperature TAO. In this embodiment, as the TAO increases from the low temperature range to the high temperature range, the blowing mode is sequentially switched from the face mode to the bilevel (B / L) mode to the foot mode.

  Next, the target opening degree of the inside / outside air switching door 6 is calculated in step S7. The inside / outside air suction mode is determined by calculating the suction opening degree TPI which is the target opening degree of the inside / outside air switching door 6. In the present embodiment, the target opening temperature TAPI is set to increase from 0% to 100% as the target blowing temperature TAO increases from the low temperature range to the high temperature range. Here, the target opening degree TPI = 0% of the inside / outside air switching door 6 is the opening degree in the all inside air mode (REC mode) in which the inside air introduction port 3 is fully opened and the outside air introduction port 4 is fully closed. The opening degree TPI = 100% is an opening degree in the full outside air mode (FRS mode) in which the inside air introduction port 3 is fully closed and the outside air introduction port 4 is fully opened.

  Next, in step S8, the target cooling temperature TEO of the evaporator 9 is calculated. The target cooling temperature TEO is a target temperature for cooling the air blown into the vehicle interior by the evaporator 9, and is a temperature necessary for adjusting the temperature and humidity of the air blown into the vehicle interior. This target cooling temperature TEO is calculated based on the above-described target blowing temperature TAO, outside air temperature Tam, and the like.

  Specifically, the target cooling temperature TEO is calculated so as to decrease as the target blowing temperature TAO decreases, and in the low temperature range of the outside air temperature Tam, the TEO has the outside air temperature Tam to prevent fogging of the window glass W. It is calculated so as to decrease with decreasing.

  Next, step S9 is control of the compressor 11, and the control current In supplied to the electromagnetic capacity control valve 11b is calculated. That is, basically, a temperature deviation En (En = Te−TEO) between the actual evaporator blown air temperature Te and the target cooling temperature TEO is calculated, and Te is brought close to TEO based on the temperature deviation En. The output duty value is calculated based on the following formula (3) by a feedback control method such as proportional-integral control (PI control).

  The control current In is calculated as an amount (In = Duty) corresponding to the duty value in the equation (3). Therefore, the control current In and the Duty value correspond to the current capacity that the compressor 11 should discharge, that is, the current target value.

Duty (n) = Duty (n−1) + kp (En (n) −En (n−1))
+ (Θ / Ti) × En (n) (3)
Here, n is a number indicating the number of operations, kp is a proportional constant, θ is a sampling time, and Ti is an integral constant. Also, En (n) is the current temperature deviation, En (n-1) is the previous temperature deviation, Duty (n) is the current Duty value, and Duty (n-1) is the previous Duty value.

  In this embodiment, when TEO decreases, the temperature deviation En increases, so the control current In increases so that Te approaches TEO. Since the discharge capacity of the compressor 11 increases due to the increase in the control current In, the refrigerant discharge flow rate of the compressor 11 also increases.

  During warm-up control under heating conditions, when the blower 8 is in a stopped state in step S4, the control current In is also set to 0, and the discharge capacity of the compressor 11 in the operating state is set to 0, When the blower 8 is switched to the blown (on) state in response to an increase in the engine coolant temperature Tw, the compressor 11 is also operated with a discharge capacity corresponding to the control current In output at that time.

  Next, it progresses to step S10, and the actuator drive part (11b, 7, 18, 25, 8b of various apparatuses) from the air-conditioning control apparatus 30 so that the control state calculated and determined by said step S4-S7 and S9 may be obtained. , 12b), an output signal is output. Thereafter, the process returns to the control process of step S2.

  Next, the processing content of the compressor control in step S9 will be specifically described based on FIG. The control routine shown in FIG. 4 is repeatedly executed in the execution of the main routine of FIG.

  First, in step S201, Duty1 (n), which is a target value for controlling the compressor 11, is calculated based on the above equation (3), that is, in equation (3), Duty (n) is calculated as Duty1 (n). .

  Next, in step S202, whether or not the operating state in the current calculation of the blower 8 is switched from the stopped state (OFF, blower motor voltage = 0) to the blowing state (ON) with respect to the state in the previous calculation. Determined. In the present embodiment, the switching from the OFF to the ON of the blower 8 is caused by increasing the engine cooling water temperature Tw detected by the water temperature sensor 35 in the step S4, so that the water temperature threshold (for example, 30 to 60 ° C.) is increased. This is done when the predetermined value in the range is reached.

  If the blower 8 is not switched from OFF to ON, that is, if the blower 8 is in the blower stopped (OFF) state or the blower (ON) state, whether or not the blower is ON in step S203. Is determined and the determination result is NO, that is, when the blower 8 is stopped (OFF), Duty2 = 0 is set in step S205.

  If the determination result is YES in step S203, that is, if the blower 8 is in the blowing state (ON), it is determined in step S204 whether or not the compressor 11 is in the ON mode. Specifically, the determination in step S204 is not made based on the output duty value of the compressor 11, but is made according to the setting state of the air conditioner switch 40 and the operating state of the blower 8. That is, when the compressor 11 is set to the operating state by the air conditioner switch 40 and the blower 8 is in the ON state, YES determination is made that the compressor 11 is in the ON mode. In the case of YES determination, Duty2 = 100 is set in the next step S206.

  On the other hand, even if the blower 8 is in the ON state, if the compressor 11 is set in the stopped state according to the setting condition of the air conditioner switch 40 read in step S2, the determination result in step S204 is NO. In this case, Duty2 = 0 is set in the next step S205.

  If it is determined in step S202 that the blower 8 has been switched from OFF to ON (YES determination), it is determined in step S207 whether the state of the compressor 11 has been switched from the previous OFF mode to the ON mode this time. Determined. This determination is also the same as in step S204, and is determined according to the set state of the air conditioner switch 40 and the ON / OFF operating state of the blower 8. Therefore, if the determination result in step S202 is YES, that is, if the blower 8 is switched from OFF to ON and the compressor 11 is in operation, the determination in step S207 is YES, that is, the compressor 11 Is determined to have been switched to the ON mode, and the process proceeds to the next step S208.

  If the compressor 11 remains in the OFF mode even in the case of YES determination in step S202, the determination result in step S207 is NO, the process proceeds to the next step S203, and the same process as in the case where there is no change in the state of the blower 8 Will continue.

  In step S208, Duty1 (n) is replaced with a preset fixed value α, not the value calculated by the iterative calculation of equation (3) in step S201. Thereafter, in step S206, Duty2 = 100 (%) is set.

  Note that when the blower is turned ON in response to the increase in the engine coolant temperature Tw, the evaporator blowout air temperature Te as the evaporator temperature also increases due to the radiation of the engine coolant. Therefore, at this time, the temperature deviation En is relatively large. Thereby, Duty1 (n) calculated according to the temperature deviation En in step S201 is also a relatively large value.

  Accordingly, the fixed value α in step S208 can be set to be lower than the value of Duty1 (n) calculated in step S201, for example, about 30%.

  In either case, in step S209, the output duty value as the target value for control of the compressor 11 is determined as the smaller value of Duty1 (n) and Duty2 in the following equation (4). Then return to the main routine.

Duty = MIN (Duty1 (n), Duty2) (4)
The output duty value calculated by the above processing is set as follows according to the current (current) state of the blower 8 and the compressor 11. Note that “step” is omitted.

  a) During normal time when the blower 8 is in the blowing (ON) state in the auto mode and the compressor 11 set to the operating state is operating at the discharge capacity based on the output Duty value, Duty 1 (n) in S201 Since the blower 8 remains in the ON state, NO is determined in S202, YES is determined in S203, YES is determined in S204 because the compressor 11 is in the ON mode, and Duty2 = 100 in S206. In step S209, the output duty value is set to Duty1 (n). Accordingly, the compressor 11 continues to operate at the discharge capacity of the calculated target value Duty1 (n).

  b) During the warm-up control in which the engine coolant temperature Tw is lower than the water temperature threshold value, Duty1 (n) is calculated in S201, and since the blower 8 is stopped, NO determination is made in S202, and NO determination is made in S203. Duty2 = 0 is set in S205, and the output Duty value is set to 0 in S209. With this output duty value, the discharge capacity of the compressor 11 becomes zero.

  When Tw is lower than the water temperature threshold value, the calculation of the target value Duty1 (n) is continued based on the above equation (3) in S201 while the process of b) is repeated.

  c) Even during warm-up control, Duty1 (n) is repeatedly calculated in S201. When the engine cooling water temperature Tw rises and reaches the water temperature threshold value during the warm-up control, the blower 8 that has been turned off until then is turned on, thereby the determination result in S202 becomes YES, and accordingly Thus, the compressor 11 is switched from the OFF mode to the ON mode. In accordance with the determination result in S202, the determination in S207 is YES, and in the next S208, Duty1 (n) = α is replaced. In S206, Duty2 = 100 is set. In S209, the output Duty value is set to α. Therefore, the compressor 11 whose discharge capacity = 0 until then operates (ON) with a small discharge capacity based on the fixed value α smaller than the calculated value Duty1 (n).

  When the air conditioner control device 30 is operating in the manual mode according to the setting on the air conditioning operation panel 37 and the blower 8 is stopped even if Tw is higher than the water temperature threshold, the passenger will automatically When the switch 42 is turned on and switched to the auto mode, the blower 8 is automatically turned on, and the air conditioner switch 40 automatically operates the compressor 11 in conjunction with the auto switch 42. Also in this case, similarly to the above c), the compressor 11 starts the operation with a small discharge capacity based on the output duty value = α by the process of S201 → S202 YES → S207 YES → S208 → S206 → S209. be able to.

  An example of the change in the operating state by the control processing of the present embodiment as described above is shown in the time diagram of FIG. In FIG. 5, the ignition is turned on at time t = 0, and the processing of the main routine (FIG. 3) is started. Here, the target cooling temperature TEO is a constant value. Further, when the ignition is ON, the auto switch 42 is turned on, and the air conditioner switch 40 is set so that the compressor 11 is in an operating state.

  Along with the ignition ON, Duty1 (n) is repeatedly calculated according to the temperature deviation En = Te−TEO. During this time, when the engine coolant temperature Tw is lower than the threshold value, the blower 8 is maintained in the OFF state by the warm-up control, and the duty of 0, that is, the discharge capacity of the compressor 11 is set to 0 by the process b). . In addition, according to the rise of Tw, the blown air temperature Te of the evaporator 9 in the OFF state rises due to the influence of the radiation.

  After that, when Tw rises and reaches the water temperature threshold value, the blower 8 is switched from OFF to ON at the time indicated by “Blower ON” in FIG. 5, and the compressor 11 is in the OFF state accordingly. Switches from ON to ON. At this time, the output duty value is replaced by α from Duty1 (n) by the process of c), and the compressor 11 starts up (begins operation) with a low discharge capacity according to Duty = α (<Duty1 (n)). With the discharge capacity based on this fixed value α, the evaporator blowing air temperature Te does not decrease excessively, and therefore the evaporator 9 does not freeze.

  As the time elapses, the blowing state (ON) of the blower 8 and the ON state of the compressor 11 continue, and the compressor 11 operates with the discharge capacity of Duty 1 (n) by the processing of c) above, The air temperature Te is controlled so as to approach the target cooling temperature TEO.

  For comparison, FIG. 5 also shows an operating state by conventional control. That is, when the compressor 11 is started and controlled with the target value Duty1 (n) itself calculated by the repetitive calculation up to that point in time when “Blower ON” is performed without performing the duty replacement as in the present embodiment, a thin line Show. As shown in the figure, in the conventional control, when the blower 8 is switched from the stopped state to the blower state, the compressor 11 is started at the calculated target value Duty1 (n), so that the evaporator 9 is supercooled and Te. Becomes below the freezing point, that is, the evaporator 9 is frozen.

(Second Embodiment)
Next, a second embodiment will be described. The second embodiment is different from the first embodiment only in the process of step S208 in the compressor control routine shown in FIG. 4, and the other configurations are the same. Only the parts different from the first embodiment will be described below.

  In the second embodiment, as the control target value Duty of the compressor 11 when starting the compressor 11 when the blower 8 is switched from the stopped state to the blower state, Duty1 (n) calculated at that point is predetermined. Replace with the value β. That is, in step S208, the calculation of Duty1 (n) = β is performed.

  The predetermined value β to be replaced in the second embodiment is given as a function of the outside air temperature Tam detected by the outside air temperature sensor 31. That is, as shown in FIG. 6, the predetermined value β is fixed to a lower limit value (25%) when Tam <0 ° C. and to an upper limit value (45%) when Tam> 20 ° C., and 0 ≦ Tam ≦ 20. In the range, the predetermined value β is set so as to increase from the lower limit value to the upper limit value as Tam increases. Note that Tam used in step S208 can be a value detected by the outside air temperature sensor 31 when the blower 8 is switched from the stopped state to the blower state.

  The predetermined value β shown in FIG. 6 can be regarded as a value reflecting the heat load state of the evaporator 9 according to the outside air temperature Tam. That is, when Tam is low, the heat load of the evaporator 9 is small, and when Tam is high, the heat load of the evaporator 9 is large. In order to set the temperature in the vicinity of the evaporator 9, that is, the temperature at which the evaporator blown air temperature Te is not frozen, when the heat load of the evaporator 9 is small, the compressor 11 is compared with the case where the heat load is large. Therefore, it is necessary to limit the discharge capacity to a smaller value.

  Therefore, when the blower 8 is switched from the stopped state to the blower state, the duty as the target value of the discharge capacity of the compressor 11 when starting the compressor 11 is replaced with a predetermined value β that is a function of the outside air temperature Tam. Thus, the operating state of the compressor 11 is limited to reduce the discharge capacity of the compressor 11 when Tam is low, or the discharge capacity of the compressor 11 when Tam is high, depending on the outside air temperature Tam. Can be limited to higher values.

  As described above, in the second embodiment, the discharge capacity of the compressor 11 is limited to an appropriate value, the evaporator 9 is prevented from freezing regardless of the change in the outside air temperature Tam, and the evaporator 9 The cooling capacity can be maintained.

(Third embodiment)
Next, a third embodiment will be described. The third embodiment is different from the first and second embodiments only in the process of step S208 in the compressor control routine shown in FIG. 4, and the other configurations are the same. Only the parts different from the first and second embodiments will be described below.

  In the third embodiment, as the control target value Duty of the compressor 11 when the compressor 11 is started when the blower 8 switches from the stopped state to the blown state, Duty1 (n) calculated at that time is predetermined. Replace with the value γ. That is, in step S208, a calculation of Duty1 (n) = γ is performed.

  The predetermined value γ to be replaced in the third embodiment is given as a function of the evaporator blown air temperature Te detected by the evaporator temperature sensor 34. That is, as shown in FIG. 7, the predetermined value γ is fixed to the lower limit value (25%) when Tem <0 ° C. and to the upper limit value (45%) when Te> 20 ° C., and 0 ≦ Te ≦ 20. In the range, the predetermined value γ is set to increase from the lower limit value to the upper limit value as Te increases. Note that Te used in step S208 can be a value detected by the evaporator temperature sensor 34 when the blower 8 is switched from the stopped state to the blower state.

  The predetermined value γ shown in FIG. 7 can be regarded as a value reflecting the heat load state of the evaporator 9 according to the evaporator blown air temperature Te. That is, when Te is low, the heat load of the evaporator 9 is small, and when Te is high, the heat load of the evaporator 9 is large. In order to set the temperature in the vicinity of the evaporator 9, that is, the temperature at which the evaporator blown air temperature Te is not frozen, when the heat load of the evaporator 9 is small, the compressor 11 is compared with the case where the heat load is large. Therefore, it is necessary to limit the discharge capacity to a smaller value.

  Therefore, when the blower 8 is switched from the stopped state to the blower state, the duty as the target value of the discharge capacity of the compressor 11 when starting the compressor 11 is set to a predetermined value γ as a function of the evaporator blown air temperature Te. By replacing with, the operating state of the compressor 11 is limited so as to reduce the discharge capacity of the compressor 11 when Te is low, or when Te is high, according to the evaporator blown air temperature Te. The discharge capacity of the compressor 11 can be limited to a higher value.

  As described above, in the third embodiment, the discharge capacity of the compressor 11 is limited to an appropriate value to prevent the evaporator 9 from freezing regardless of the change in the evaporator blown air temperature Te, and the evaporation The cooling capacity of the vessel 9 can be maintained.

(Fourth embodiment)
Next, a fourth embodiment will be described. The fourth embodiment is different from the first to third embodiments only in the process of step S208 in the compressor control routine shown in FIG. 4, and the other configurations are the same. Only the parts different from the first to third embodiments will be described below.

  In the third embodiment, the control target value Duty of the compressor 11 when starting the compressor 11 when the blower 8 switches from the stopped state to the blower state is not a duty 1 (n) calculated at that time but a predetermined value. Replace with the value λ. That is, in step S208, the calculation of Duty1 (n) = λ is performed.

  The predetermined value λ to be replaced in the fourth embodiment is calculated by the following formula (5).

λ = α−20 × f (TPI) × f (SPD) × f (Tam) (5)
Here, α is a fixed value (for example, 30), and the functions f (TPI), f (SPD), and f (Tam) are set as the characteristics shown in FIGS. 8, 9, and 10, respectively.

  That is, as shown in FIG. 8, the function f (TPI) is calculated from TPI = 0 (REC mode) to TPI = 100 (FRS) with respect to the intake opening TPI given to the servomotor 7 of the inside / outside air switching door 6. F (TPI) is set to increase from 0 to 1 as it increases to (mode).

  Further, as shown in FIG. 9, the function f (SPD) is fixed to 0 when SPD <10 km / h and 1 when SPD> 60 km / h with respect to the vehicle speed SPD detected by the vehicle speed sensor 36. In the range of 10 ≦ SPD ≦ 60, f (SPD) is set to increase from 0 to 1 as the SPD increases.

  Further, as shown in FIG. 10, the function f (Tam) is fixed to 1 at Tam <5 ° C. and fixed to 0 at Tam> 20 ° C. with respect to the outside air temperature Tam detected by the outside air temperature sensor 31. In the range of 5 ≦ Tam ≦ 20, f (Tam) is set so as to decrease from 1 to 0 as Tam increases.

  Note that the suction opening degree TPI, the vehicle speed SPD, and the outside air temperature Tam used in step S208 can be set values and detection values at the time when the blower 8 is switched from the stopped state to the blower state.

  Therefore, the predetermined value λ calculated by Expression (5) based on these functions f (TPI), f (SPD), and f (Tam) is the FRS mode that is the condition that the heat load of the evaporator 9 is the smallest. When SPD ≧ 60 km / h and Tam ≦ 5 ° C., the smallest value α-20 is obtained. Conversely, the maximum value α is obtained in the REC mode, SPD ≦ 10 km / h, and Tam ≧ 20 ° C., which is the condition with the largest heat load on the evaporator 9.

  Thereby, according to the heat load state of the evaporator 9, the predetermined value λ is decreased as the heat load is reduced. Therefore, the compressor 11 is started when the blower 8 is switched from the stopped state to the blower state. By replacing the duty as the target value of the discharge capacity with the predetermined value λ, the discharge capacity of the compressor 11 is limited to be smaller when the heat load is small according to the heat load state of the evaporator 9. Alternatively, when the heat load is large, the discharge capacity of the compressor 11 can be limited to a higher value.

  As described above, in the fourth embodiment, the discharge capacity of the compressor 11 is limited to an appropriate value, regardless of the change in the heat load state of the evaporator 9, that is, the inlet opening TPI, the vehicle speed SPD. In addition, the evaporator 9 can be prevented from freezing and the cooling capacity of the evaporator 9 can be maintained regardless of changes in the outside air temperature Tam.

(Fifth embodiment)
Next, a fifth embodiment will be described. The fifth embodiment is different from the first to fourth embodiments in that the compressor control routine is changed to that shown in FIG. 11 instead of that shown in FIG. 4, and the other configurations are the same. Only the parts different from the first to fourth embodiments will be described below.

  In the fifth embodiment, the processing content of the compressor control in step S9 of the main routine (FIG. 3) will be specifically described based on the flowchart shown in FIG. The control routine shown in FIG. 11 is also repeatedly executed in the execution of the main routine of FIG. 3 as in the first to fourth embodiments.

  First, in step S301, it is determined whether or not IG has been turned on (ON) based on a signal from the ignition switch (IG). If it is determined that the IG has been switched from OFF to ON, the process proceeds to step S305. If the IG state does not change, that is, if the IG remains ON, the process proceeds to step S302.

  In step S305, the initial setting of Duty1 (n-1) is performed. Specifically, using a fixed value α (for example, 30%), Duty1 (n−1) = α is set. After this initial setting, the process proceeds to step S302.

  In step S302, it is determined whether or not the blower 8 is stopped (OFF). If the determination result is NO, that is, if the blower 8 is in a stopped state (blower OFF), the process proceeds to step S303. If the determination result is YES, that is, if the blower 8 is in a blower state (blower ON), the process proceeds to step S306.

  In step S303, Duty1 (n-1) is held. That is, Duty1 (n) = Duty1 (n−1). Thereafter, in step S304, Duty2 = 0 is set.

  On the other hand, if it is determined in step S302 that the blower is ON, in step S306, Duty1 (n) is calculated by the equation (6) as in the equation (3).

Duty1 (n) = Duty1 (n-1) + kp (En (n) -En (n-1))
+ (Θ / Ti) × En (n) (6)
In the next step S307, it is determined whether or not the compressor 11 is in the ON mode. Specifically, as in step S204 in the first to fourth embodiments, when the compressor 11 is set to the operating state by the air conditioner switch 40 and the blower 8 is in the ON state (blower ON), the compressor 11 is determined to be in the ON mode.

  If the determination result in step S307 is NO, that is, if the compressor 11 is not in the ON mode, Duty2 = 0 is set in step S304, and if the determination result is YES, that is, if the compressor 11 is in the ON mode, the process proceeds to step S308. Thus, Duty2 = 100 is set.

  Then, after each of Duty2 is set in Step S304 or S308, in the next Step S309, the output Duty value as the target value for control of the compressor 11 is Duty1 (n) in the above equation (4). And the smaller value of Duty2. After that, the process returns to the main routine.

  The output duty value calculated by the above calculation is set as follows according to the current (current) state of the blower 8 and the compressor 11.

  a) When the air blower 8 is in the air blowing (ON) state in the auto mode and the compressor 11 set to the operating state is operating at the discharge capacity based on the output duty value, the determination in S301 is NO. In step S302, NO is determined because the blower 8 is in an ON state, Duty 1 (n) is calculated in step S306, and in step S307, it is determined YES because the compressor 11 is in the ON mode. In step S308, Duty2 = 100 is set, and the output duty value is set to Duty1 (n) in S309. Therefore, the compressor 11 operates with the discharge capacity of the calculated target value Duty1 (n).

  b) Immediately after the ignition switch is turned on (OFF → ON), a YES determination in S301 results in an initial setting of Duty1 (n−1) = α in S305, and Tw is lower than the water temperature threshold in the next S302. Therefore, the blower 8 is in a stopped state (OFF state), that is, the determination result is YES, Duty 1 (n−1) initially set in S 303 is held, Duty 2 = 0 is set in S 304, and the output Duty value in S 309 Is set to 0. As a result, the discharge capacity of the compressor 11 becomes zero.

  c) During the warm-up control in which the engine cooling water temperature Tw is lower than the water temperature threshold value, the determination in S301 is NO because IG is ON, and Tw is still low in S302 and the blower 8 remains OFF. Therefore, YES is determined, Duty1 (n-1) held until the previous time is continuously held in S303, Duty2 = 0 is set in S304, and the output Duty value is set to 0 in S309. As a result, the discharge capacity of the compressor 11 is maintained at 0. During the period until Tw reaches the water temperature threshold, the calculation of Duty1 (n) is not performed while the process of c) is repeated.

  d) When the engine cooling water temperature Tw rises and reaches the water temperature threshold value during the warm-up control, the blower 8 enters the blower (ON) state. Therefore, after NO determination in S301, NO determination is made by switching ON the blower 8 in S302, and the calculation of Duty1 (n) is started by Expression (6) in the next S306. As Duty1 (n−1) in this calculation, Duty1 (n−1) = α held in S303 until the previous time is used. In next S307, the compressor 11 is determined to be in the ON mode (YES determination) according to the ON state of the blower 8, and in S308, Duty2 = 100 is set. In S309, the output Duty value is Duty1 (n) calculated in S306. ).

  By the processing in d), the compressor 11 that has been set to discharge capacity = 0 until then operates (starts) at Duty1 (n). In this case, Duty1 (n) is the first calculation. Therefore, the PI calculation value is obtained by Equation (6) based on the initially set Duty1 (n−1) = α and the temperature deviation En. Therefore, the compressor 11 can start operation with a discharge capacity limited to a relatively small value.

  An example of the change in the operating state by the control processing of the fifth embodiment as described above is shown in the time diagram of FIG. In FIG. 12, the ignition is turned on at time t = 0, and the processing of the main routine (FIG. 3) is started. Here, the target cooling temperature TEO is a constant value. When the ignition is on, the auto switch 42 is turned on, and the air conditioner switch 40 is set to the on mode.

  At time t = 0, with the ignition ON, the above processing b) causes the duty to be initially set to Duty1 (n−1) = α, and since the cooling water temperature Tw is lower than the water temperature threshold, the blower 8 is in a stopped state (OFF). It remains. This state is continued until Tw reaches the threshold value by the process of c).

  When Tw reaches the threshold value, the blower 8 changes from the stop state to the blower state (ON) at the time indicated by “Blower ON” in the figure, and the on mode is set accordingly. The compressor 11 being turned on is also turned on. The control target value Duty of the compressor 11 at this time is calculated based on the initial calculation Duty1 (n), that is, based on the held initial setting Duty1 (n−1) = α and the temperature deviation En. The value calculated by PI is given by 6) (the above processing d)).

  Since the first-time PI calculated value Duty (n) is lower than the calculated value Duty1 (n) when the constant calculation is performed, the compressor 11 is started with a relatively low discharge capacity. Thereby, the evaporator blowing air temperature Te is not excessively lowered, and therefore the evaporator 9 is not frozen.

  Then, as time elapses, the blowing state (ON) of the blower 8 and the ON state of the compressor 11 are continued, and the compressor 11 is operated with the calculated discharge capacity by Duty 1 (n) by the process of d), The evaporator blowing air temperature Te is controlled so as to approach the target cooling temperature TEO.

  FIG. 12 also shows an operating state by conventional control similar to FIG. 5 for comparison. As a result of this comparison, the compressor 11 is started with a low discharge capacity by stopping the calculation of Duty1 (n) while the blower 8 is stopped and holding the initial setting value Duty1 (n−1) = α. It can be seen that 9 is not supercooled and therefore no freezing occurs.

(Sixth embodiment)
Next, a sixth embodiment will be described. The sixth embodiment is different from the fifth embodiment only in the process of step S305 in the compressor control routine shown in FIG. 11, and the other configurations are the same. Only the parts different from the fifth embodiment will be described below.

  In the sixth embodiment, the initial setting value Duty1 (n−1) of the duty value after the ignition is turned on is not a fixed value but set to a value calculated by the following equation (7).

Duty1 (n−1) = α + kp × En + (θ / Ti) × En (7)
Here, α is a fixed value, kp is a positive proportionality constant, θ is a sampling time, and Ti is an integration constant. En is a temperature deviation (Te-TEO) between the evaporator blown air temperature Te and the target cooling temperature TEO at the time of initial setting.

  That is, the initial setting value Duty1 (n−1) is set as a value obtained by correcting the fixed value α so as to increase as Te increases. Thus, the initial set value Duty1 (n−1) is a relatively large value when the heat load of the evaporator 9 is large, that is, when Te is high, according to the heat load state of the evaporator 9 when the ignition is ON. Conversely, when the heat load of the evaporator 9 is small, that is, when Te is low, the value is relatively small. Therefore, when the compressor 11 starts to operate in response to the ON state of the blower 8, when the heat load of the evaporator 9 is small, the discharge capacity of the compressor 11 is relatively small and prevents the evaporator 9 from being overcooled. However, when the cooling capacity is exhibited and the heat load of the evaporator 9 is large, the discharge capacity of the compressor 11 is relatively large, and the cooling capacity can be exhibited while preventing the evaporator 9 from being overcooled.

(Other embodiments)
In each of the above embodiments, an example is shown in which the evaporator temperature sensor 34 that is disposed in the air blowing portion of the evaporator 9 and detects the evaporator blowing air temperature Te as the temperature of the evaporator 9 is used as the evaporator temperature detecting means. However, the present invention is not limited to this, and the temperature of the fin may be detected as the temperature of the evaporator 9 by a thermistor disposed directly on the fin of the evaporator 9.

  In each of the above embodiments, the compressor 11 is an example using a swash plate type variable displacement compressor. However, the present invention is not limited to this, and for example, a scroll variable displacement compressor may be used. Furthermore, although the example which uses rotation of the engine E as mentioned above was shown as a drive source of the compressor 11, it is not restricted to this, For example, you may use what is called an electric compressor driven with an electric motor. In the electric compressor, the rotational speed of the electric motor that determines the discharge capacity of the electric compressor can be controlled by the output duty value described above.

1 is an overall system configuration diagram showing a first embodiment of the present invention. It is a characteristic view which shows the relationship between the control current of the capacity | capacitance control valve in 1st Embodiment, target differential pressure | voltage, and target flow volume. It is a flowchart which shows the outline | summary of the whole air-conditioning control of 1st Embodiment. It is a flowchart which shows the specific example of the compressor control of 1st Embodiment. It is a time diagram which shows the example of the change of the operating state of 1st Embodiment. It is a figure which shows the characteristic of the function (beta) which determines Duty value in 2nd Embodiment. It is a figure which shows the characteristic of the function (gamma) which determines Duty value in 3rd Embodiment. It is a figure which shows the characteristic of the function f (TPI) which determines Duty value in 4th Embodiment. It is a figure which shows the characteristic of the function f (SPD) which determines Duty value in 4th Embodiment. It is a figure which shows the characteristic of the function f (Tam) which determines Duty value in 4th Embodiment. It is a flowchart which shows the specific example of the compressor control of 5th Embodiment. It is a time diagram which shows the example of the change of the operating state of 5th Embodiment.

Explanation of symbols

2 ... case, 2a ... air passage, 6 ... inside / outside air switching door (inside / outside air switching means),
7 ... Servo motor (inside / outside air switching means), 9 ... Evaporator (cooling heat exchanger),
11 ... Variable displacement compressor, 11b ... Capacity control valve (capacity control means),
30 ... Air conditioning control device (air conditioning control means).

Claims (7)

A blower (8) for blowing air toward the air-conditioning target space;
An evaporator (9) disposed in the blower passage (2a) of the blower for cooling the air;
A compressor (11) for sucking and compressing refrigerant on the outlet side of the evaporator;
A calculation means (S9) for calculating a target value (Duty) of a discharge capacity to be generated in the compressor by an operation based on a deviation (En) between the evaporator temperature (Te) and a target cooling temperature (TEO); ,
Capacity control means (S10) for adjusting the cooling capacity of the evaporator by controlling the discharge capacity of the compressor according to the calculated target value;
The calculation means replaces the target value calculated at the time when the blower switches from the stopped state to the blower state with a predetermined value (α, β, γ, λ) lower than the calculated target value. The vehicle air conditioner characterized in that the predetermined value is a target discharge capacity of the compressor at the time of switching. The vehicle air conditioner according to claim 1, wherein the predetermined value is set according to a heat load state of the evaporator. An outside air temperature detecting means (31) for detecting the outside air temperature (Tam) is provided,
The vehicle air conditioner according to claim 2, wherein the calculating unit corrects the predetermined value (β) to be replaced by the detected outside air temperature. Evaporator temperature detection means (34) for detecting the temperature (Te) on the air outlet side of the evaporator,
The vehicle air conditioner according to claim 2, wherein the calculating means corrects the predetermined value (γ) to be replaced by a temperature detected by the evaporator temperature detecting means detected at the switching time. . Means (6, S7) for setting the air inlets (3, 4) to the air passage to the inside air introduction state or the outside air introduction state, means (36) for detecting the vehicle speed (SPD), and detecting the outside air temperature An outside air temperature detecting means (31)
The calculation unit corrects the predetermined value (λ) to be replaced by the set inlet port state (TPI), the detected vehicle speed, and the outside air temperature. The vehicle air conditioner described. A blower (8) for blowing air toward the air-conditioning target space;
An evaporator (9) disposed in a blower passage of the blower for cooling the air;
A compressor (11) for sucking and compressing refrigerant on the outlet side of the evaporator;
Calculating means (S9) for calculating a target value (Duty) of a discharge capacity to be generated in the compressor by a calculation based on a deviation (En) between the temperature (Te) of the evaporator and a target cooling temperature (TEO); ,
Capacity control means (S10) for adjusting the cooling capacity of the evaporator by controlling the discharge capacity of the compressor according to the calculated target value;
The calculation means fixes the target value to a predetermined value (α, Duty1 (n−1)) when the blower is in a stopped state, and the target value when the blower switches from the stopped state to the blower state. The vehicle air conditioner is calculated based on the fixed value. Evaporator temperature detection means (34) for detecting the temperature (Te) on the air outlet side of the evaporator,
The calculation means corrects the fixed value (Duty1 (n-1)) by a detected temperature of the evaporator temperature detection means detected when a power-on switch (IG) to the calculation means is activated. The vehicle air conditioner according to claim 6.

Images