JPH0840055A - Compressor control device of air conditioner for vehicle - Google Patents

Abstract

PURPOSE:To prevent the unnecessary restart prohibiting time by performing operation so as to shortly correct the restart prohibiting time of a compressor as an outside air temperature becomes low on the basis of a detected outside air temperature. CONSTITUTION:First of all, operation (PROG5B) of the restart prohibiting time T of a compressor is performed from an outside temperature Tamb just after the compressor is stopped. In this operation, since a cooling demand becomes strong as the outside air temperature Tamb becomes high and rotating speed of the compressor becomes high, the time until a pressure difference between the high pressure side and the low pressure side of a cooling cycle falls within a compressor restart possible range P becomes long. Therefore, the restart prohibiting time T of the compressor is set short as the outside air temperature Tamb (just before) at compressor stopping time becomes low. Therefore, since the restart prohibiting time obtained by the operation from the outside air temperature can be set in the proper time, useless stopping of the compressore can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle air conditioner for electrically driving a compressor constituting a cooling cycle, wherein the restart of the compressor is stopped for a predetermined time after the compressor is stopped. Of the compressor control device.

[0002]

2. Description of the Related Art In a conventional vehicle air conditioner, for example, a vehicle air conditioner mounted on an electric vehicle uses an electric motor as a means for driving a compressor forming a part of a cooling cycle. This type of air conditioner, for example, reduces the load on the electric motor at the time of restart, and in order to achieve smooth restart and power saving, the pressure difference between the high pressure side and the low pressure side of the cooling cycle after the compressor is stopped is reduced. The restart of the compressor is prohibited until it is within a predetermined range (Japanese Utility Model Laid-Open No. 56-149841).

Therefore, the compressor re-driving preventive device disclosed in Japanese Patent Laid-Open No. 63-294460 discloses a start preventing means for stopping the compressor for a predetermined time after stopping the compressor, and an outside air temperature. It consists of a temperature detection unit and a control unit that corrects the start prevention unit based on the outside air temperature, and the stop time of the compressor can be changed depending on the outside air temperature. When the temperature is low, the pressure difference between the high pressure and the low pressure is small, so the time for balancing the pressure difference between the high pressure and the low pressure becomes long. Therefore, it is disclosed that the time until the compressor is restarted (restart prohibition time) is set to be long. There is.

[0004]

However, after the compressor is stopped, the time until the pressure difference between the high-pressure side and the low-pressure side of the compressor settles within a predetermined range and restart is possible (restart prohibition time) is It has been confirmed by experiments that it is approximately proportional to the outside air temperature and that it is affected by factors other than the outside air temperature that affect the cooling cycle.

Therefore, the present invention sets the compressor restart prohibition time which is substantially proportional to the outside air temperature, and
Another object of the present invention is to provide a compressor control device for an air conditioner for a vehicle, which can set an optimum restart prohibition time of the compressor by correcting the restart prohibition time of the compressor according to a factor affecting the cooling cycle.

[0006]

Therefore, the present invention is
The upstream side has an inside air inlet and an outside air inlet, and an intake door that adjusts the opening degree of the inside air inlet and the outside air inlet, and sucks air from the inside air inlet and the outside air inlet to the downstream side. A blower to blow air and at least a compressor,
An evaporator that constitutes a cooling cycle together with a condenser and an expansion valve, cools the air sent by the blower, a heater core that is arranged on the downstream side of the evaporator and that heats the passing air, and air that has passed through the evaporator. In an air conditioner for a vehicle having air passing through the heater core and an air mix door diverted to air bypassing the heater core, an outside air temperature detecting means for detecting an outside air temperature, and an outside air temperature detected by the outside air temperature detecting means. Based on the above, there is provided a restart prohibition time calculation means for calculating the restart prohibition time of the compressor so that the stop time becomes shorter as the outside air temperature becomes lower.

Further, there is provided a correction means for correcting the restart prohibition time calculated by the restart prohibition time calculation means by a factor affecting the refrigerant pressure in the cooling cycle (claim 2).

Further, a factor affecting the pressure of the refrigerant in the cooling cycle is defined as an air volume passing through the evaporator,
The correction means may make a correction such that the cycle start inhibition time is shortened as the air volume increases (claim 3), and a factor affecting the refrigerant pressure in the cooling cycle is immediately before the compressor is stopped. The number of compressor revolutions may be set, and the correction means may correct the start inhibition time as the compressor revolution number becomes lower (claim 4).

Further, the factor affecting the refrigerant pressure in the cooling cycle is the intake air temperature of the evaporator, and the correction means corrects so that the start prohibition time becomes shorter as the intake air temperature of the evaporator becomes higher. Alternatively, the factor that affects the refrigerant pressure in the cooling cycle may be the opening degree of the intake door, and the correction means may increase the start prohibition time as the amount of outside air introduced decreases. The correction may be made according to the present invention (claim 6).

Furthermore, the factor that affects the refrigerant pressure in the cooling cycle is the ignition switch closing state, and the correction means sets the ignition switch to OF.
In the case of F, the start prohibition time may be corrected so as to be longer (claim 7), and the factor affecting the refrigerant pressure in the cooling cycle is the fan switch closing state, and the correction means is the fan switch. When is OFF, the start prohibition time may be lengthened.

[0011]

Therefore, according to the first aspect of the invention, based on the outside air temperature detected by the outside air temperature detecting means,
Since the calculation is performed so that the restart prohibition time of the compressor is shortened as the outside air temperature is lower, it is possible to prevent the unnecessary restart prohibition time, so that the above-mentioned problem can be achieved.

According to the second aspect of the present invention, the restart prohibition time of the compressor calculated by the restart prohibition time calculating means is corrected by the correcting means by a factor affecting the refrigerant pressure in the cooling cycle. Therefore, the above problems can be achieved.

According to a third aspect of the present invention, the factor that affects the refrigerant pressure in the cooling cycle is the air volume passing through the evaporator, and the temperature of the evaporator increases as the air volume passing through the evaporator increases after the compressor is stopped. Therefore, since the pressure difference between the high pressure and the low pressure in the cooling cycle quickly settles within the predetermined range, the correction means corrects the cycle start inhibition time so as to become shorter as the air volume increases.

According to a fourth aspect of the present invention, the factor affecting the refrigerant pressure in the cooling cycle is the compressor rotation speed immediately before the compressor is stopped, and the lower the rotation speed immediately before the compressor is stopped, the higher the cooling cycle high pressure. Since the pressure becomes low, the pressure difference between the high pressure and the low pressure in the cooling cycle settles quickly within a predetermined range, so that the correction means corrects the start prohibition time to shorten as the compressor rotation speed decreases. To do.

Further, in the invention according to claim 5, the factor affecting the refrigerant pressure in the cooling cycle is the intake air temperature of the evaporator, and the temperature of the evaporator rises as the evaporator intake air temperature after the compressor is stopped increases. Since the pressure difference between the high pressure and the low pressure in the cooling cycle quickly settles within a predetermined range, the correction means corrects the start prohibition time to shorten as the intake air temperature of the evaporator increases. To do.

Further, in the invention according to claim 6, the factor that affects the refrigerant pressure in the cooling cycle is the opening of the intake door, and the temperature of the evaporator increases as the opening of the intake door increases the amount of outside air introduced. Is increased, the pressure difference between the high and low pressures in the cooling cycle quickly settles within a predetermined range.Therefore, the correction means corrects the start prohibition time to shorten as the amount of outside air introduced increases. To do so.

According to the seventh aspect of the present invention, the factor affecting the refrigerant pressure in the cooling cycle is the ignition switch ON state, and when the ignition switch is OFF, all the air conditioning control devices are stopped. Since it takes a long time for the high-low pressure difference in the cooling cycle to settle within a predetermined range, the correction means corrects the start prohibition time to be long when the ignition switch is OFF.

According to the eighth aspect of the invention, the factor affecting the refrigerant pressure in the cooling cycle is the fan switch closing state, and when the fan switch is OFF, the air volume passing through the evaporator is zero. Since it takes a long time for the pressure difference between the high pressure and the low pressure in the cooling cycle to settle within a predetermined range because the temperature rise of the evaporator slows down, the correction means corrects the start prohibition time to be long.

[0019]

Embodiments of the present invention will be described below with reference to the drawings.

In the vehicle air conditioner 1 shown in FIG. 1, an inside air inlet 3 and an outside air inlet 4 are opened on the upstream side of an air conditioning duct 2, and an intake door that opens and closes the inside air inlet 3 and the outside air inlet 4. 6 are arranged. This intake door 6
An air blower (fan) 7 is disposed downstream of the air intake duct 6, and air is sucked from the inside air introduction port 3 and the outside air introduction port 4 according to the opening ratio of the intake door 6 and is blown to the downstream side of the air conditioning duct 2.

An evaporator 8 as a heat exchanger for cooling is arranged downstream of the fan 7 so that the air sucked by the fan 7 first passes through the evaporator 8. The evaporator 8 includes a compressor 10 driven by an electric motor (motor) 9, a condenser 11,
The expansion valve 12 and the receiver dryer 13 are connected in series by piping to form a cooling cycle 14.

A heater core 15 is disposed downstream of the evaporator 8 to heat passing air. An air mix door 16 that divides the air passing through the heater core 15 and the air bypassing the heater core 15 is arranged on the upstream side of the heater core 15. In this embodiment, P is used as the heater core 15.
Although a CT heater is used for heating by electric power, the heat source in the heater core 15 is not particularly limited.

At the most downstream of the air conditioning duct 2, the differential air outlet 1
7, vent outlet 18, foot outlet (heat outlet)
19 is opened, and is selected by the mode door 20 and opened.

In the above vehicle air conditioner 1, the inside air, the outside air, or the air-fuel mixture sucked by the drive of the fan 7 is sent to the downstream side of the air conditioning duct 2 and first the evaporator 8 is supplied.
It is cooled by passing through. The air cooled by the evaporator 8 is divided by the air mix door 16 into air passing through the heater core 15 and air bypassing the heater core 15. As a result, the air that has passed through the heater core 15 and has been heated and the air that has bypassed the heater core 15 and that has been cooled are mixed with the air at the desired temperature on the downstream side of the heater core 15 and selected by the mode door 20. It blows out from the air outlets 17, 18, and 19 into the passenger compartment to control the temperature inside the passenger compartment.

Further, a microcomputer 21 is provided to control the vehicle air conditioner 1.
The microcomputer 21 includes at least a central processing unit (CPU), a read only memory (ROM), a random access memory (RAM), an input / output port (I / I).
O) and the like are known per se.

The microcomputer 21 detects an outside air temperature sensor 22 for detecting an outside air temperature (T _amb ), a temperature sensor 23 for detecting an evaporator intake air temperature (T _int ), and an evaporator blown air temperature (T _out ). Temperature sensor 24, heater core wake side temperature (T _h )
The temperature sensor 25 for detecting the temperature, the position detection sensor 26 for detecting the position of the intake door 6, and the detection signal from the discharge side refrigerant temperature (T _d ) of the compressor 10 are supplied to the multiplexer (MPX) 27 and the A / D converter 28. Entered through
Further, a setting signal is input from the operation panel 29, processed according to a predetermined program, and then output as a control signal.

The operation panel 29 includes a temperature setter (T / L) 30 which is a slide switch for setting a _set temperature (T _set ) in the passenger compartment, and a thrust switch for setting the fan voltage (V _B ) of the fan 7. FAN setting device (F /
L) 31, a VENT switch 32 for opening the vent outlet 18, a B / L switch 33 for opening the vent outlet 18 and the foot outlet 19 at a predetermined ratio, a foot outlet 1
FOOT switch 34 for opening only 9 and foot outlet 19 and differential outlet 17 for D / F opening at a predetermined ratio
The switch 35, the DEF switch 36 that opens only the differential air outlet 36, and the REC switch 3 that circulates and sets the inside air circulation (REC) mode and the outside air introduction (FRE) mode.
7 and an A / C switch 38 that circulates and sets ON / OFF of driving of the compressor, and outputs each setting signal to the microcomputer 21.

The control signals output from the microcomputer 21 are the drive circuits 39, 40, 41, 42,
The actuators 47, 48, 49 for driving the intake door 6, the air mix door 16, and the mode door 20, the fan 7, the motor 9 for driving the compressor 10, and the heater core 15 are operated by being input to the motors 43, 44.

An embodiment of the compressor control according to the present invention executed in the microcomputer 21 will be described below with reference to the flow charts shown in FIGS.

In the compressor control started from step 100, it is judged in step 110 whether or not the ignition switch is turned on (IG ON?), And if the ignition switch is off (N), step 2 is executed.
If the ignition switch is ON (Y), the process proceeds to step 120.

At step 120, it is judged whether the compressor 10 is forcibly stopped (forcibly stopped?). If it is forcibly stopped (Y), the routine proceeds to step 125, where the air conditioning control is performed. Returning to the main control routine (not shown) to be performed, if the forced stop is not in progress (N), the process proceeds to step 130.

In step 130, it is judged whether or not the compressor 10 is under start-up control (start-up control?), And if it is under start-up control (Y), the routine proceeds to step 270, where start-up control is performed. If not (N), go to step 140.

In step 140, it is judged whether or not an abnormality has occurred in the cooling cycle 14 (abnormality occurrence?).
Is performed and an abnormality has occurred (Y), the process proceeds to step 330, and if there is no abnormality (N), step 15
Go to 0.

In step 150, the FAN switch (F
/ L) 31 input status is judged (F / L ON?),
If the FAN switch (F / L) 31 is not turned on (N), the process proceeds to step 280, and if it is turned on (Y), the process proceeds to step 160.

At step 160, it is judged whether the A / C switch (air conditioner switch) 38 is turned on (A / C SW
ON? ) Is determined and the A / C switch is OFF (N), the process proceeds to step 330 and the A / C switch is turned off.
In the case of N (Y), the process proceeds to step 170.

In step 170, it is determined whether the compressor 10 is operating (COMP operating?). If it is operating (Y), the steps 180 to 200 are bypassed and the process proceeds to step 210. If it is not in operation (N), the process proceeds to step 180.

At step 180, the outside air temperature T _amb is determined. In this determination, when the outside air temperature T _amb is lower than the predetermined value (B), the routine proceeds to step 190, where the evaporator blown air temperature T _out is the predetermined value t ₃ (for example, 3 °).
It is determined (T _out <t ₃ ?) Whether or not it is lower than C). If it is lower than the predetermined value t ₃ (Y), the process proceeds to step 330. If it is equal to or larger than the predetermined value t ₃ (N), the process proceeds to step 200.

When the outside air temperature T _amb is larger than the predetermined value (A) in step 180, step 190 is bypassed and the process proceeds to step 200 where the evaporator blown air temperature T _out is set to the predetermined value t _4. (Eg 2
C)) or not (T _out <t ₄ ?). In this determination, the evaporator blown air temperature T
_{If out} is smaller than the predetermined value t ₄ (Y), step 3
30. If it is larger (N), go to step 210. It should be noted that in the determination of step 180, t ₁ (for example, 30 ° C.) and t ₂ at the time of transition from A to B and B to A.
Hysteresis is formed in the range of (for example, 33 ° C.).

In step 210, it is judged whether or not there is a start request for the compressor 10 (COMP start request is there?). If there is a start request (Y), the process proceeds to step 270. If there is no start request. For (N), the process proceeds to step 220.

In step 220, the M of the compressor 10 is set by the program 3 (PROG 3) shown in FIG.
The AX rotation speed N1 is set by the temperature setter 30, the outside air temperature T _amb, and the evaporator blown air temperature T _out .

In step 401 shown in FIG. 8,
Voltage division ratio (%) depending on the knob position of the temperature setting device (T / D)
Is calculated. Based on this partial pressure ratio, in step 402, the characteristic lines C, D, selected by the outside air temperature T _amb ,
From E (shown in box 403), the MAX rotation speed (primary setting rotation speed) N1 is calculated. In the box 404, when the evaporator outlet air temperature T _out at the time of starting the compressor is equal to or lower than a predetermined value (G), the primary set speed N of the compressor is set for 60 seconds after starting the compressor.
This is a control for fixing 1 to N _ID (about 1500 rpm).
In this case, in the state indicated by F, the above box 403
And calculation of the primary set speed N1 are performed.

1 calculated in step 220
The next set rotational speed N1 is subjected to rotational speed correction (PROG 1) based on the compressor discharge side temperature (T _d ) shown in FIG. 9 in the next step 230. The rotation speed correction based on the compressor discharge side temperature T _d aims to suppress the increase in the refrigerant pressure in view of the fact that the higher the refrigerant temperature on the high pressure side during the cooling restart prohibition time period 14 is, the higher the refrigerant high pressure is. The secondary set rotational speed N2 is derived by gradually decreasing the primary set rotational speed N1 by a predetermined value N _R1 (for example, 1500 rpm) as the refrigerant temperature T _d rises. .

Further, the secondary set rotational speed N2 calculated in step 230 is subjected to rotational speed correction (PROG 2) by the evaporator outlet air temperature T _out shown in FIG. 10 in the next step 240. The rotation speed correction based on the evaporator blown air temperature T _out is performed for the purpose of suppressing the rise of the refrigerant pressure in view of the fact that the higher the refrigerant pressure becomes, the higher the refrigerant high pressure becomes. The third set rotational speed N3 is derived by gradually lowering the second set rotational speed N2 by a predetermined value N _R2 (for example, 1000 rpm) as T _out increases. Then, the compressor is driven by setting the third set rotational speed N3 as the final set rotational speed.

In step 250, the above-mentioned step 240
It is judged whether or not the third set rotational speed N3 set in step 3 is greater than the predetermined rotational speed N _RPM (N3 <N _RPM ?).
If the next set rotation speed N3 is smaller than the predetermined rotation speed N _{RPM, the} routine proceeds to step 260, where the third set rotation speed N3 is set to N _RPM.
It is fixed to. This results in step 370.
Then, the process returns to the main control routine executed by the microcomputer 21 (not shown), and the compressor always operates in steps 220, 230, 2 within the range of the minimum rotation speed N _RPM or more.
It is rotated at the third set rotational speed N3 set at 40. The predetermined rotation speed N _RPM is preferably 1500 rpm.

Further, when it is determined in step 110 that the ignition switch (not shown) is not turned on (OFF) or in step 150, the FAN setting device (F / L) 31 is turned on. If it is determined that there is no (OFF), the process proceeds to step 280 and the compressor 10 is stopped (COMPOF).
F) is set.

Thereafter, in step 290, it is determined whether or not the compressor has just stopped (COMP ON → OF).
F? ) Is made and it is determined that the compressor is not immediately after the stop (N), the process proceeds to step 300,
The compressor 10 is stopped.

If it is determined that the compressor 10 has just stopped (Y), the process proceeds to step 315.
Compressor forced stop control (PROG5B) is executed. This compressor forced stop control (PROG5B)
Is the one shown in Fig. 5, and the ignition switch is turned off.
Alternatively, when the FAN setter (F / L) 31 is OFF, the restart inhibition time T is calculated according to the characteristic line shown in the figure. This characteristic line is set linearly from the forced stop time t ₄₁ to t ₄₃ in the range where the outside air temperature T _amb immediately before the compressor is stopped is γ ₁ to γ ₂ . It is desirable to set γ ₁ to 21 ° C., γ ₂ to 35 ° C., t ₄₁ to 60 seconds and t ₄₃ to 240 seconds.

As a result, the PROG of step 315
Since the compressor restart prohibition time T is set by the compressor restart prohibition time T set in 5B, the fan 7 is stopped when the ignition switch is turned OFF or the FAN setter 31 is turned OFF. Since the restart prohibition time corresponding to the delay in the temperature return of the evaporator can be set, the compressor restarts when the compressor stop time is insufficient and the pressure difference between the high pressure side and the low pressure side has not settled sufficiently. Can be prevented.

After that, the routine returns from step 370 to the main control routine executed by the microcomputer 21, and the above-mentioned compressor control is repeatedly executed at predetermined time intervals.

If it is determined in step 130 that startup control is being performed (Y) or if there is a compressor activation request in step 210 (Y),
The routine proceeds to step 270, where the startup control of the compressor is executed. When the compressor rotation speed reaches a predetermined rotation speed (for example, 3600 rpm) within a predetermined time (for example, 60 seconds) after starting the compressor, the start control of the compressor continues the predetermined rotation speed until the predetermined time elapses. It controls.

If it is determined in step 140 that an abnormality has occurred (Y), then step 160 is performed.
When it is determined that the A / C switch is OFF in the determination (N), the step 190 or the step 2 is performed.
When the evaporator blown air temperature T _out is lower than the predetermined temperature in the determination of 00 (Y), the process proceeds to step 330 and the stop of the compressor 10 is set. The reason why the compressor 10 is stopped in the determinations of step 190 and step 200 is that it is determined that the evaporator 8 may freeze.

Furthermore, in the determination at step 340,
It is determined that the compressor 10 has just stopped (COMP
ON → OFF? ) Is performed (Y), step 365
To the outside air temperature T _amb according to the characteristic line shown in FIG.
To calculate the compressor restart inhibition time (T) (PRO
G5A) is performed, and if not immediately after the stop (N), the routine proceeds to step 350, the compressor 10 is stopped, and the routine returns from the step 370 to the main control routine. It should be noted that the setting of the compressor restart prohibition time is necessary especially in an air conditioner for an electric vehicle in which the compressor is driven by an electric motor, and the power consumption of the motor 9 is suppressed as much as possible, and the starting torque applied to the motor 9 at the time of starting. In order to achieve a stable compressor start by reducing the above, the start of the compressor is suspended until the pressure difference between the high pressure side and the low pressure side of the cooling cycle falls within a predetermined range.

[0053] calculation of the restart prohibition time T of the compressor (PROG5B) is first calculated from the outside air temperature T _amb immediately after the compressor stop restart prohibition time T of the compressor. As is clear from the experimental results shown in FIG. 11 (b), this calculation is based on the fact that the higher the outside air temperature T _{amb, the} stronger the cooling demand and the higher the rotational speed of the compressor. It takes a long time until the pressure difference falls within the restartable range Pλ of the compressor.
For this reason, as shown in FIG. 11A, the lower the outside air temperature T _amb when the compressor is stopped (immediately before), the shorter the restart prohibition time T of the compressor is set. As a result, the restart prohibition time T calculated from the outside air temperature can be set to an appropriate time, and unnecessary stop of the compressor can be prevented, so that comfortable air conditioning can be achieved.

Further, it has been confirmed that the time until the pressure difference between the high pressure and the low pressure of the compressor is balanced varies depending on other environmental factors. Therefore, the restart prohibition time T of the compressor is set to the above value. Further, by further compensating for other environmental factors (factors that affect the refrigerant pressure in the cooling cycle), it is possible to obtain a more optimal compressor restart prohibition time T.

For this purpose, the control for correcting the restart prohibition time calculated by the outside air temperature by the factor affecting the refrigerant pressure in the cooling cycle will be described with reference to the flowcharts shown in FIGS. 6 and 7.

In the compressor control started from step 100, it is judged in step 110 whether or not the ignition switch is turned on (IG ON?). If the ignition switch is off (N), step 3 is executed.
If the ignition switch is ON (Y), the process proceeds to step 120.

In step 120, it is judged whether or not the compressor 10 is forcibly stopped (forcibly stopped?). If PROG4 indicated by 12 is executed and the forced stop is not in progress (N), the routine proceeds to step 130.

In step 130, it is judged whether or not the compressor 10 is under start-up control (start-up control?), And if it is under start-up control (Y), the routine proceeds to step 270, where start-up control is performed. If not (N), go to step 140.

At step 140, it is judged whether or not an abnormality has occurred in the cooling cycle 14 (abnormality occurrence?).
Is performed, and if an abnormality has occurred (Y), the process proceeds to step 28, and if there is no abnormality (N), step 150
Proceed to.

At step 150, the FAN switch (F
/ L) 31 input status is judged (F / L ON?),
If the FAN switch (F / L) 31 is not turned on (N), the process proceeds to step 330, and if it is turned on (Y), the process proceeds to step 160.

At step 160, it is judged whether the A / C switch (air conditioner switch) 38 is turned on (A / C SW
ON? ) Is determined and the A / C switch is OFF (N), the process proceeds to step 280, and the A / C switch is turned off.
In the case of N (Y), the process proceeds to step 170.

In step 170, it is judged whether the compressor 10 is operating (COMP operating?). If it is operating (Y), the steps 180 to 200 are bypassed and the process proceeds to step 210. If it is not in operation (N), the process proceeds to step 180.

At step 180, the outside air temperature T _amb is determined. In this determination, when the outside air temperature T _amb is lower than the predetermined value (B), the routine proceeds to step 190, where the evaporator blown air temperature T _out is the predetermined value t ₃ (for example, 3 °).
It is determined whether or not it is lower than C) (T _out <t ₃ ?), And when it is lower than the predetermined value t ₃ (Y), the process proceeds to step 280. If it is equal to or larger than the predetermined value t ₃ (N), the process proceeds to step 200.

When the outside air temperature T _amb is larger than the predetermined value (A) in the judgment of step 180, step 190 is bypassed and the routine proceeds to step 200, where the evaporator blown air temperature T _out is the predetermined value t _4. (Eg 2
C)) or not (T _out <t ₄ ?). In this determination, the evaporator blown air temperature T
_{If out} is smaller than the predetermined value t ₄ (Y), step 2
If it is larger (N), proceed to step 210. It should be noted that in the determination of step 180, t ₁ (for example, 30 ° C.) and t ₂ at the time of transition from A to B and B to A.
Hysteresis is formed in the range of (for example, 33 ° C.).

In step 210, it is judged whether or not there is a start request for the compressor 10 (COMP start request is there?). If there is a start request (Y), the process proceeds to step 270. If there is no start request. For (N), the process proceeds to step 220.

In step 220, the MAX rotation speed N1 of the compressor 10 is set to the temperature setter 30, the outside air temperature T _amb and the evaporator blown air temperature T by the program 3 (PROG 3) shown in FIG.
It is set by the _out.

In step 401, the temperature setter (T
The voltage division ratio (%) is calculated by the knob position of / D).
With this partial pressure ratio, in step 402, the outside air temperature T
Characteristic lines C, D, E selected by _amb (box 4
03) to MAX rotation speed (primary setting rotation speed) N1
Is calculated. In addition, what is shown in the box 404 is
Evaporator air temperature T _out when the compressor is started
If is less than or equal to a predetermined value (G), 6
The compressor's primary setting speed N1 is set to N _ID (about 1
The control is fixed at 500 rpm). In this case, in the state indicated by F, the selection of the box 403 and the calculation of the primary set speed N1 are performed.

1 calculated in step 220
The next set rotational speed N1 is subjected to rotational speed correction (PROG 1) based on the compressor discharge side temperature (T _d ) shown in FIG. 9 in the next step 230. The rotation speed correction based on the compressor discharge side temperature T _d aims to suppress the increase in the refrigerant pressure in view of the fact that the higher the refrigerant temperature on the high pressure side during the cooling restart prohibition time period 14 is, the higher the refrigerant high pressure is. The secondary set rotational speed N2 is derived by gradually decreasing the primary set rotational speed N1 by a predetermined value N _R1 (for example, 1500 rpm) as the refrigerant temperature T _d rises. .

Further, the secondary set rotational speed N2 calculated in step 230 is subjected to rotational speed correction (PROG 2) by the evaporator outlet air temperature T _out shown in FIG. 10 in the next step 240. The rotation speed correction based on the evaporator blown air temperature T _out is performed for the purpose of suppressing the rise of the refrigerant pressure in view of the fact that the higher the refrigerant pressure becomes, the higher the refrigerant high pressure becomes. The third set rotational speed N3 is derived by gradually lowering the second set rotational speed N2 by a predetermined value N _R2 (for example, 1000 rpm) as T _out increases. Then, the compressor is driven by setting the third set rotational speed N3 as the final set rotational speed.

In Step 250, the above Step 240
It is judged whether or not the third set rotational speed N3 set in step 3 is greater than the predetermined rotational speed N _RPM (N3 <N _RPM ?).
If the next set rotation speed N3 is smaller than the predetermined rotation speed N _{RPM, the} routine proceeds to step 260, where the third set rotation speed N3 is set to N _RPM.
It is fixed to. This results in step 370.
Then, the process returns to the main control routine executed by the microcomputer 21 (not shown), and the compressor always operates in steps 220, 230, 2 within the range of the minimum rotation speed N _RPM or more.
It is rotated at the third set rotational speed N3 set at 40. The predetermined rotation speed N _RPM is preferably 1500 rpm.

If it is determined in step 130 that the startup control is being performed (Y) or if the determination in step 210 is that there is a compressor startup request (Y), the process proceeds to step 270 to execute compressor startup control.
When the compressor rotation speed reaches a predetermined rotation speed (for example, 3600 rpm) within a predetermined time (for example, 60 seconds) after starting the compressor, the start control of the compressor continues the predetermined rotation speed until the predetermined time elapses. It controls.

If it is determined in step 140 that an abnormality has occurred (Y), then step 160 is performed.
When it is determined that the A / C switch is OFF in the determination (N), the step 190 or the step 2 is performed.
If the evaporator blown air temperature T _out is lower than the predetermined temperature in the determination of 00 (Y), the process proceeds to step 280 and the stop of the compressor 10 is set. The reason why the compressor 10 is stopped in the determinations of step 190 and step 200 is that it is determined that the evaporator 8 may freeze.

Furthermore, in the determination of step 290,
It is determined that the compressor 10 has just stopped (COMP
ON → OFF? (Y), step 310.
Then, the operation (PROG 4) of the compressor restart inhibition time (T) described below is performed. If not immediately after the stop (N), the process proceeds to step 300 to stop the compressor 10 and returns from step 370 to the main control routine. . It should be noted that the setting of the compressor restart prohibition time is necessary especially in an air conditioner for an electric vehicle in which the compressor is driven by an electric motor, and the power consumption of the motor 9 is suppressed as much as possible, and the starting torque applied to the motor 9 at the time of starting. In order to achieve a stable compressor start by reducing the above, the start of the compressor is suspended until the pressure difference between the high pressure side and the low pressure side of the cooling cycle falls within a predetermined range.

The calculation of the compressor restart prohibition time T (PROG 4) is performed by first determining the primary restart prohibition time T of the compressor from the outside air temperature T _amb immediately after the compressor is stopped.
Calculate ₁ As is clear from the experimental results shown in FIG. 11 (b), this calculation is based on the fact that the higher the outside air temperature T _{amb, the} stronger the cooling demand and the higher the rotational speed of the compressor. It takes a long time until the pressure difference falls within the restartable range Pλ of the compressor. For this reason, as shown in FIG. 11A, the higher the outside air temperature T _amb when the compressor is stopped (immediately before), the longer the restart prohibition time of the compressor is set. In other words, the restart prohibition time is set shorter as the outside air temperature is lower.

As a result, in the first embodiment for correcting the restart prohibition time T shown in FIG. 12, step 50 is performed.
1, the compressor restart prohibition time (primary restart prohibition time T ₁ ) is calculated from the outside air temperature T _amb according to the characteristic of step 501 (forced stop 2) set based on the characteristic shown in FIG. To be done. Specifically, when the outside air temperature T _amb is in the range of γ ₁ to γ ₂ , the primary restart inhibition time T
₁ intended to be set according to the characteristics of suspended 2 linearly varied t ₄₂ from t _41, gamma ₁ is 21 ° C, gamma
_It is desirable that ₂ is 35 ° C., t ₄₁ is 60 seconds, and t ₄₂ is 180 seconds.

Further, in step 502, it is shown that the primary restart inhibition time T ₁ calculated in step 501 is corrected by the FAN voltage V _B when the compressor is stopped. As shown in FIG. 13, the FAN voltage V _B is first calculated in step 601 by the knob position of the FAN setting device (F / L) 31 to calculate a voltage division ratio (%), and the characteristic line of step 602 is calculated by the voltage division ratio. Based on this, the FAN voltage V _B is set.
The Hi relay in step 602 is a relay that is driven only when the maximum air volume is obtained, and when the relay is turned on, the FAN voltage is stepped up at once.

In step 502 shown in FIG. 12,
The FAN voltage V _B calculated in steps 601 and 602 corrects the primary restart inhibition time T ₁ calculated in step 501 along the characteristic line shown in step 502. This correction is such that, when the fan voltage V _B is high and the air volume is large, the temperature rise rate of the evaporator 8 becomes large, and the pressure difference (P _d between the high pressure side and the low pressure side of the cooling cycle 14 _).
-P _s) is intended to be made in view of the fact that the shorter the time to settle within a predetermined range, said with increasing FAN voltage primary restart prohibition time T ₁ predetermined time shorter T ₁
The corrected restart prohibition time T is _calculated according to the characteristic that changes linearly up to −t _c1 . The maximum correction amount t _c1
Is preferably 60 seconds.

As a result, when the air volume is large, the restart prohibition time T can be set short, so that the occurrence of fog on the windshield due to the stop of the compressor can be prevented,
In addition, it is possible to smoothly start up the compressor.

Further, in the second embodiment for correcting the restart prohibition time shown in FIG. 14A, the correction of the primary restart prohibition time T _{1 in} step 502 is carried out immediately before the compressor is stopped or the compressor stop command is issued. It shows that it is performed by the compressor rotation speed at the time. This is shown in FIG.
As shown in (b), the lower the compressor speed when the compressor is stopped, the smaller the pressure difference (P _d −P _s ) between the high pressure side and the low pressure side of the cooling cycle 14, and this pressure difference is the compressor startable region. Since it takes a short time to settle in, the primary restart prohibition time T ₁ is corrected according to the characteristic line shown in FIG. 14A, and the corrected restart prohibition time T is set.

Specifically, when the compressor rotation speed immediately before the compressor is stopped is the first predetermined rotation speed R ₁ , the primary restart inhibition time T ₁ becomes T ₁ -t _c2 , and the second predetermined rotation speed N is obtained. _{In 2} , the correction is performed according to the characteristic line such that the correction amount of the primary restart inhibition time T ₁ becomes zero. In this characteristic, it is desirable to set the lower limit maximum correction amount t _c2 to 30 seconds, and the restart prohibition time T increases linearly even when the rotation speed exceeds the _second predetermined rotation speed N _2. It is set to do. The first predetermined rotation speed R ₁ is 1500 rpm, and the second predetermined rotation speed R is
₂ is preferably 3000 rpm.

As a result, the primary restart inhibition time T ₁ can be corrected by the compressor speed immediately before the compressor is stopped, and the optimum compressor restart inhibition time T can be set. Sufficient load can be prevented when the compressor is started. Furthermore, since it is possible to reduce unnecessary stop time of the compressor, it is possible to prevent windshield fogging due to stop of the compressor.

In the third embodiment for correcting the restart prohibition time shown in FIG. 15, the correction of the primary restart prohibition time T _{1 in} step 502 is performed by the evaporator intake air temperature T _int when the compressor is stopped. Is shown.
As shown in FIG. 15B, the higher the evaporator intake air temperature T _int is, the faster the temperature rise of the evaporator 8 is, so that the pressure difference between the high pressure side and the low pressure side of the cooling cycle 14 settles within a predetermined range. As shown in FIG. 15A, as the evaporator suction air temperature T _int rises from T _int1 to T _int2 , the primary restart inhibition time T ₁ to T _The restart prohibition time T is set to _1- t _c3 . More specifically, the maximum correction amount t _c3 is 3
It is desirable that T _int1 is 21 ° C. and T _int2 is 35 ° C.

As a result, the temperature of the air passing through the evaporator (evaporator intake air temperature) becomes 1
Since it is possible to correct the next restart prohibition time T ₁ and set the optimum compressor restart prohibition time T, it is possible that the compressor stop time becomes insufficient and an extra load is applied at the time of starting the compressor. Can be prevented. Furthermore, since it is possible to reduce unnecessary stop time of the compressor, it is possible to prevent windshield fogging due to stop of the compressor.

In the fourth embodiment for correcting the restart prohibition time shown in FIG. 16, the correction of the primary restart prohibition time T _{1 in} step 502 is performed by correcting the outside air temperature T _amb when the compressor is stopped.
Difference between the intake air temperature of the evaporator and T _int (T _amb
-T _int ). This is the primary restart inhibition time T ₁ set by the outside air temperature T _amb ,
The temperature of the air actually passing through the evaporator (evaporator intake air temperature T _int ) is to be corrected, and the outside air temperature T _amb and the evaporator intake air temperature T
_When the temperature difference from _int is a small value δ ₁ , the correction amount is set to zero and the restart prohibition time T is set to the primary restart prohibition time T ₁ .
When the temperature difference is a large value δ ₂ , it is corrected to T ₁ + t _c4 for a long time. Specifically, the maximum correction amount t _c4 is 60
Seconds, δ ₁ is preferably 0 ° C, and δ ₂ is preferably 15 ° C.

As a result, when the temperature of the air passing through the evaporator is low due to the air cooled in the passenger compartment, the temperature difference from the outside air temperature T _amb becomes large, so that the temperature rise rate of the evaporator decreases, so that the compressor increases. The primary restart prohibition time T ₁ is corrected to be long. As a result, it is possible to prevent the compressor from restarting in a state where the compressor stop time is insufficient and the pressure difference between the high pressure side and the low pressure side has not settled sufficiently.

Further, in the fifth embodiment for correcting the restart prohibition time shown in FIG. 17, the correction of the primary restart prohibition time T _{1 in} step 502 is performed by the outside air introduction amount when the compressor is stopped. Shows. This is shown in FIG.
As shown in (b), as the outside air introduction amount decreases, the pressure difference between the high-pressure side and the low-pressure side of the cooling cycle 14 takes a long time to settle within a predetermined range. Therefore, as the outside air introduction amount decreases, The primary restart inhibition time T ₁ is corrected to be longer. Specifically, FIG.
As shown in FIG. 7 (a), when the outside air introduction amount is σ ₁ (%), the correction amount of the primary restart inhibition time T ₁ is set to zero, and when the outside air introduction amount is σ ₂ (%), T ₁ The corrected restart prohibition time T is set to be + t _c5 . The maximum correction amount t _c5 is preferably 30 seconds, σ ₁ is 80%, and σ ₂ is 20%.

As a result, since the primary restart prohibition time T ₁ set by the outside air temperature is corrected by the outside air introduction amount, when the outside air introduction amount is large, the primary restart prohibition time T ₁ remains unchanged. Set the restart prohibition time T after correction,
Since the restart inhibition time T can be corrected to increase as the amount of circulation of the internal air increases, the compressor can be operated in a state where the stop time of the compressor is insufficient and the pressure difference between the high pressure side and the low pressure side has not settled sufficiently. It is possible to prevent the restart.

The calculation (PROG 4) of the restart prohibition time T of the compressor 10 described above is performed in the step 12 above.
Even if it is determined that the forced stop is in progress (Y) in the determination of 0, it is executed in step 320. As a result, the compressor 10 is prohibited from being restarted during the restart prohibition time T calculated by PROG 4.

Further, when it is determined in step 110 that the ignition switch (not shown) is not turned on (OFF) or in step 150, the FAN setting device (F / L) 31 is turned on. If it is determined that there is no (OFF), the process proceeds to step 370 and the compressor 10 is stopped (COMPOF).
F) is set.

Thereafter, at step 340, it is determined whether or not the compressor has just stopped (COMP ON → OF).
F? ) Is made and it is determined that the compressor is not immediately after the stop (N), the process proceeds to step 350,
The compressor 10 is stopped.

If it is determined that the compressor 10 has just stopped (Y), the routine proceeds to step 360,
Compressor forced stop control (PROG 5) is executed. This compressor forced stop control (PROG 5)
Is shown in FIG. 18, and the ignition switch OF
When the F or FAN setting device (F / L) 31 is OFF (that is, when the compressor is stopped. FAN voltage V
_{If B} = 0V), change the characteristic line from forced stop 2 to forced stop 1. In this forced stop 1, the outside air temperature T _amb immediately before the compressor is stopped is linearly set from the forced stop time t ₄₁ to t ₄₃ within the range of γ ₁ to γ _2.
Forced stop 2 which calculates the primary restart prohibition time T ₁ of G 4
The characteristic line of is corrected so as to be increased by a predetermined value. It is desirable to set γ ₁ to 21 ° C., γ ₂ to 35 ° C., and t ₄₃ to 240 seconds.

As a result, the PROG of step 360 is obtained.
Since the compressor restart prohibition time T is set by the compressor restart prohibition time T set in 5, the fan 7 is stopped when the ignition switch is turned off or the fan setting device 31 is turned off. Since the restart prohibition time corresponding to the delay in the temperature return of the evaporator can be set, the compressor restarts when the compressor stop time is insufficient and the pressure difference between the high pressure side and the low pressure side has not settled sufficiently. Can be prevented.

After that, the routine returns from step 370 to the main control routine executed by the microcomputer 21, and the compressor control is repeatedly executed at predetermined time intervals. Further, in the above embodiment, the correction of the _first restart inhibition time T ₁ set (calculated) in step 501 was performed for each of the factors that affect the refrigerant pressure of the cooling cycle 14, It is also possible to make a complex correction with a plurality of factors. For example, the primary restart inhibition time T ₁ calculated by the outside temperature is
Is corrected by the compressor rotational speed of the compressor is stopped immediately before calculating the second restart prohibition time T _2, further the second restart prohibition time T ₂ the evaporator suction air temperature T _int
Alternatively, the restart prohibition time T after the correction may be obtained. As a result, the restart prohibition time T can be obtained more finely.

[0094]

As described above, according to the present invention, the restart prohibition time of the compressor is reduced by the restart prohibition time calculating means based on the outside air temperature detected by the outside air temperature detecting means. By calculating so that it becomes as short as possible, it is possible to set the restart prohibition time that matches the high and low pressure balance time of the cooling cycle,
The restart prohibition time of the compressor can be minimized and comfortable air conditioning control can be performed.

Further, since the restart prohibition time calculated by the restart prohibition time calculating means is corrected by the factor that affects the refrigerant pressure of the cooling cycle by the correcting means, the high pressure side and the low pressure side of the cooling cycle are corrected. It becomes possible to set the optimal restart prohibition time until the pressure difference on the side settles within the predetermined range, and it is possible to cut unnecessary restart prohibition time or prevent insufficient restart prohibition time. .

As a result, the minimum required restart prohibition time can be set, so that it is possible to suppress the occurrence of fog on the windshield due to the stop of the compressor, and the insufficient restart prohibition time causes the compressor to start. It is possible to prevent a heavy load from being applied and to improve the life of the compressor.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a vehicle air conditioner according to an embodiment of the present invention.

FIG. 2 is a flowchart showing the first half of the compressor control for calculating the restart prohibition time according to the embodiment of the present invention.

FIG. 3 is a flowchart showing a second half of the compressor control for calculating the restart prohibition time according to the embodiment of the present invention.

FIG. 4 is a characteristic diagram showing PROG 5A for calculating a restart inhibition time.

FIG. 5 is a characteristic diagram showing PROG 5B for calculating a restart inhibition time.

FIG. 6 is a flowchart showing the first half of the compressor control for calculating the restart prohibition time and correcting the restart prohibition time according to the embodiment of the present invention.

FIG. 7 is a flowchart showing the latter half of the compressor control for calculating the restart prohibition time and correcting the restart prohibition time according to the embodiment of the present invention.

FIG. 8 is a PRO for controlling the MAX rotation speed of the compressor.
It is the flowchart figure which showed G3.

FIG. 9 is a characteristic diagram showing PROG 1 that performs compressor rotation speed correction based on the compressor discharge side temperature.

FIG. 10 is a characteristic diagram showing PROG 2 for performing compressor rotation speed correction based on evaporator blown air temperature.

FIG. 11A is a characteristic diagram showing the relationship between the outside air temperature immediately before the compressor is stopped and the primary restart inhibition time T _1, and FIG. 11B is a high pressure of the cooling cycle for a predetermined outside air temperature. FIG. 6 is a characteristic diagram showing a relationship between a pressure difference between a low pressure side and a low pressure side and a time until it settles within a predetermined range.

FIG. 12 is a flowchart showing PROG 4 for calculating a restart prohibition time T of the compressor.

FIG. 13 is a flowchart showing FAN control.

FIG. 14 (a) is a characteristic diagram showing the relationship between the compressor speed immediately before the compressor is stopped and the restart prohibition time T, and FIG. 14 (b) is a graph showing a predetermined value of the compressor speed immediately before the compressor is stopped. FIG. 6 is a characteristic diagram showing the relationship between the pressure difference between the high pressure side and the low pressure side and the time until it settles within a predetermined range.

FIG. 15 (a) is a characteristic diagram showing the relationship between the temperature of the evaporator suction air when the compressor is stopped and the restart prohibition time T, and FIG. 15 (b) is a predetermined value of the evaporator suction air temperature immediately before the compressor is stopped. 5 is a characteristic diagram showing the relationship between the pressure difference between the high pressure side and the low pressure side and the time until it settles within a predetermined range.

FIG. 16 is a characteristic diagram showing the relationship between the temperature difference between the outside air temperature when the compressor is stopped and the evaporator intake air temperature and the restart prohibition time T.

FIG. 17A is a characteristic diagram showing the relationship between the amount of outside air introduced when the compressor is stopped and the restart prohibition time T;
(B) is a characteristic diagram showing the relationship between the pressure difference between the high pressure side and the low pressure side with respect to a predetermined amount of outside air introduced immediately before the compressor is stopped, and the time until it settles within a predetermined range.

FIG. 18 is a graph P showing a restart prohibition time control of the compressor.
It is a characteristic diagram which showed ROG 5.

[Explanation of symbols]

 1 Vehicle Air Conditioner 3 Inner Air Inlet 4 Outer Air Inlet 6 Intake Door 7 Blower (Fan) 8 Evaporator 9 Electric Motor (Motor) 10 Compressor 11 Condenser 12 Expansion Valve 13 Receiver Dryer 14 Cooling Cycle 15 Heater Core 16 Air Mix Door 17 Def blow Outlet 18 Vent outlet 19 Foot outlet 20 Mode door 21 Microcomputer 29 Operation panel 30 Temperature setting device (T / L) 31 FAN setting device (F / L) 37 REC switch 38 A / C switch

[Procedure amendment]

[Submission date] November 21, 1994

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Correction target item name] Figure 15

[Correction method] Change

[Correction content]

FIG. 15

Claims (8)

[Claims] 1. An inside air introduction port and an outside air introduction port, and an intake door for adjusting the opening degree of the inside air introduction port and the outside air introduction port are provided on the upstream side, and air is sucked from the inside air introduction port and the outside air introduction port. And a blower that blows air downstream, and at least a compressor, a condenser, and an expansion valve that form a cooling cycle, and an evaporator that cools the air sent by the blower, and the air that is placed downstream of this evaporator and that passes through it. In a vehicle air conditioner having a heater core that heats the air, and an air mix door that divides the air that has passed through the evaporator into the air that passes through the heater core and the air that bypasses the heater core, an outside air temperature detecting means that detects an outside air temperature. Based on the outside air temperature detected by the outside air temperature detecting means, the outside air temperature stops as the outside air temperature decreases. During compressor control device for a vehicle air-conditioning system, characterized in that is provided with a restart prohibition time calculating means for calculating a restart prohibition time of the compressor to be shorter. 2. The correction means for correcting the restart prohibition time calculated by the restart prohibition time calculation means according to a factor affecting the refrigerant pressure in the cooling cycle. Compressor control device for vehicle air conditioners. 3. A factor that affects the refrigerant pressure in the cooling cycle is an air flow rate passing through the evaporator, and the correction means corrects the cycle start prohibition time to be shortened as the air flow rate increases. A compressor control device for a vehicle air conditioner according to claim 2. 4. The factor affecting the refrigerant pressure in the cooling cycle is set to the compressor speed immediately before the compressor is stopped, and the correction means shortens the start prohibition time as the compressor speed becomes lower. The compressor controller of the vehicle air conditioner according to claim 2, wherein the compressor controller is corrected. 5. The intake air temperature of the evaporator is set as a factor that affects the refrigerant pressure in the cooling cycle,
3. The compressor control device for an air conditioner for a vehicle according to claim 2, wherein the correction means corrects the start inhibition time to be shorter as the intake air temperature of the evaporator becomes higher. 6. The opening of the intake door is a factor that affects the refrigerant pressure in the cooling cycle, and the correction means corrects the startup prohibition time to be longer as the amount of outside air introduced decreases. A compressor control device for a vehicle air conditioner according to claim 2. 7. The factor affecting the refrigerant pressure in the cooling cycle is the ignition switch closing state, and the correction means corrects the start prohibition time to be long when the ignition switch is OFF. The compressor control device of the vehicle air conditioner according to claim 2. 8. A factor that affects the refrigerant pressure in the cooling cycle is a fan switch closing state, and the correction means corrects the start prohibition time to be long when the fan switch is OFF. The compressor control device of the vehicle air conditioner according to claim 2.