JPH048625A - Car airconditioner - Google Patents

Abstract

PURPOSE:To prevent a compressor from vibration resulting from unbalance by furnishing a means to restrict the discharging capacity of compressor, while the revolving speed of a prime mover lies within No.1 specific range, so as to be smaller than the specified capacity into No.2 specific range. CONSTITUTION:Judgement whether or not the idling stabilization process is needed, is placed by reference to the sensing value Ne given by an engine revolving speed sensor 30. Fx=1 indicates that the vibration lies within the Ne region to raise problem, i.e., No.1 specific range, depending upon the discharge capacity of compressor 3. The control current Iso2U at the boundary where the discharge capacity launches into No.2 specific range, is determined from the physical quantity on the thermal load as the revolving speed Ne is in the No.1 specific range, and if the amperage Iso2 is larger than Iso2U, with a small capacity presenting a problem with vibration i.e., outside of the No.2 specific range the Iso2 is sunk below the Iso2U followed by increase of the capacity and freezing. Therefore, a magnetic clutch 31 it turned off, and the Iso2 is turned into the max. amperage Iso2max. Because therein the requisite cooling power is small, shortage of cooling power due to stop of the compressor 3 does not present any problem.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a device for optimizing the discharge capacity of a compressor in an air conditioner for an automobile and the rotational speed of the motor of the automobile, which is the power source of the compressor. .

[Conventional technology]

The conventional device is disclosed in Utility Model Application Publication No. 16219/1983, page 5, 1.
As described in lines 3 to 17, the discharge capacity of the compressor is related to the rotational speed of the motor vehicle's motor, and the rotational speed is maintained constant by the amount of adjustment related to the discharge capacity. Ta.

In addition, as described in Japanese Patent Application Laid-Open No. 1-195112,
When the rotation speed of the motor vehicle decreases, the discharge capacity is also reduced to prevent sudden fluctuations in the rotation speed of the motor during idle control.

[Problem to be solved by the invention]

The above conventional technology does not take into account the fact that when the rotational speed of the prime mover is within the first predetermined range, if the discharge capacity of the compressor falls outside the second predetermined range, vibrations due to unbalance of the compressor will increase. Although the rotational speed of the prime mover could be maintained constant, the noise and vibration generated by the compressor caused discomfort to passengers.

An object of the present invention is to prevent compressor vibrations caused by compressor imbalance.

[Means to solve the problem]

To achieve the above object, the present invention provides a motor vehicle for an automobile, a rotation speed detection means for the motor, a variable displacement compressor using the motor as a power source, a device for controlling the displacement of the compressor, and , an air conditioner for an automobile including an evaporator that cools intake air with a refrigerant circulated by the compressor, a means for detecting a physical quantity related to the discharge capacity of the compressor, and a physical quantity related to the heat load of the evaporator. The discharge capacity control device determines a physical quantity related to a predetermined discharge capacity based on the physical quantity related to the heat load, and when the rotation speed of the prime mover is within a first predetermined range, the discharge capacity control device controls the discharge capacity of the compressor. Means for limiting the capacity to a second predetermined range, which is less than the predetermined discharge capacity, is provided.

[Effect]

The present invention determines a predetermined discharge capacity that reaches the freezing limit depending on the heat load of the evaporator, and further, when the rotation speed of the prime mover is within a first predetermined range that may cause vibrations of the compressor. Since the discharge capacity of the compressor is limited within the second predetermined balanced range and below the predetermined discharge capacity, it is possible to prevent the vibration of the compressor without causing freezing, and to protect the occupants. does not cause any discomfort.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on FIGS. 1 to 12.

FIG. 1 shows a block diagram of this embodiment. In other words, it consists of the following five devices. Heat exchange device 1. Air conditioning electronic control device 2 that controls the heat exchange device 1. Compressor for cooling 3. It consists of a compressor electronic control device 4 that controls the compressor 3, an engine control electronic control device 5, and the like.

The heat exchange device 1 and the air conditioning electronic control device 2 are
This is a known device as shown in FIG. 1 of Japanese Patent No. 205504.

An overview of this embodiment will be explained. The heat exchange device 1 consists of the following three units. An intake blower unit 11 consisting of an intake door 8 that controls the intake ratio of inside air 6 or outside air 7 in the passenger compartment, and a blower 10 driven by a motor 9. A cooling unit 13 that includes an evaporator 12 that cools the engine; two air mix doors 14 and 15 that control the rate at which the cooled air is reheated;
A heater 16 that utilizes the temperature (approx. 80°C), a vent outlet 17 that blows out to the upper body, and a floor outlet 18 that blows out to the feet.
This is a heater unit 20 having a built-in mode door 19 that controls the ratio of .

The air conditioning electronic control device 2 controls a target temperature Ts given to a volume 21 linked to a temperature setting lever provided on an operation panel.
The heat exchange device 1 is controlled so that the interior of the vehicle becomes as follows.

The temperature T in the vehicle interior is determined by an upper vehicle interior temperature sensor 22 installed on the ceiling and a lower vehicle interior temperature sensor 23 located at the foot of the vehicle.
Furthermore, the detected value Ta of the outside air temperature sensor 24,
And, from the detection value 2 of the solar radiation sensor 25, the target temperature T duo, T of the vent outlet 17 and the floor outlet 18 is determined.
Decide on dto.

The intake door 8 is controlled so that the smaller the temperature difference TduO-Tdu between the vent outlet temperature Tdu detected by the vent outlet temperature sensor 26 and its target value Tduo, the greater the internal air intake ratio.

The motor 9 of the blower 10 increases the voltage 1 so that the larger the absolute value 1''rs-T,l of the temperature difference between Tr and Ts, the greater the air volume.

The air mix door 114 has a temperature difference (Tduo-"r
As du) is smaller, the proportion of airflow that bypasses the heater 16 is increased.

The air mix door l115 detects a temperature difference (T' a t o T d-) between the floor blowing temperature Tdt detected by the floor blowing wind speed sensor 27 to be described later and its target value Td1o.
The smaller the value, the more the proportion of airflow that bypasses the heater 16 is increased.

The mode door 19 is controlled using a floor airflow speed sensor 27 provided on the floor airflow 18 so that the air distribution ratio between the vent airflow 17 and the floor airflow 18 is determined based on Ta and Z.

The wind speed sensor 27 is based on the service bulletin No. 491 (BL-14) issued by Nissan Motor Co., Ltd., published in October 1988.
The principle is the same as that of the known air flow meter, as described on pages 1-64 to 11-65. That is, it consists of two thermistor sensors, one of which measures the temperature of the blown air, Tag, and the other of which generates heat to maintain a constant temperature.

The wind speed G is determined by correcting the current applied to the latter sensor with the temperature Td1.

The compressor electronic control device 4 receives information from the air conditioning electronic control device 2 and the detected value T1. of the inlet air temperature sensor 28 of the evaporator 12. and the detected value Te of the outlet air temperature sensor 29
, the magnetic clutch 31 of the compressor 3 and the control valve coil 32 are controlled based on the detected value Ne of the engine speed sensor 30. The details are shown in Figures 2 to 12.
This will be explained using the flowchart shown in the figure.

The engine control device 5 is based on service bulletin No. 578 (YAI-1, YBll) published by Nissan Motor Co., Ltd., 1988.
It has the same function as the device described on pages B-62 to B-65 published in June 2016. That is, the basic injection amount (Tp) determined by the engine intake air amount detected by the air flow meter 33
), a correction value Co determined by the detected value of the engine rotation speed sensor 30, etc. is added to determine the fuel injection amount and control the fuel injection time of the injector 34 that supplies fuel to the engine.

Next, the operation of the compressor electronic control device 4 will be explained using a processing flow of a microcomputer that performs calculations, judgments, etc. for control.

The microcomputer of this embodiment includes a central control unit (hereinafter referred to as CPU), a read-only memory (hereinafter referred to as ROM) that stores processing procedures (programs, constants),
Random access memory (hereinafter referred to as RA) that stores data
(hereinafter referred to as M), input/output terminal (hereinafter referred to as ■/○), analog-digital conversion input terminal (hereinafter referred to as A/D)
, an arbitrary width pulse output terminal (hereinafter referred to as PWM), and a serial communication input/output terminal (hereinafter referred to as SCI). For example, the microcomputer HD6305Z manufactured by Hitachi, Ltd. is used.

A crystal oscillator having a frequency of I MHz, which constitutes an oscillator that determines the basic cycle, is connected to the microcomputer. Microcomputer programs are executed repeatedly. The Bank Ground Job (hereinafter referred to as BGJ) shown in Figure 2.

The execution cycle of this embodiment is approximately 0.1 seconds), and the time interrupt function is used to execute at fixed time intervals (5 milliseconds in this embodiment). It consists of the timer job (hereinafter referred to as TIMER) shown in FIG.

After starting the BGJ in FIG. 2 with the engine switch, in step 100, the BGJ initializes Ilo, RAM, etc.
Thereafter, the processes from step 101 to step 109 are repeated.

In step 101, between the air conditioning electronic control device 2,
Data communication is performed using SCI. The following information is received from the air conditioning electronic control device 2.

That is, they are the position of the intake door 8, the air distribution ratio Ra of the floor blowout - the voltage ■1 of the motor 9, the outside air temperature Ta,
These are the target temperature Tauo of the vent blowout 17 and the detected temperature Tau.

In step 102, the temperature T0 detected by the inlet air temperature sensor 28, the temperature Te detected by the outlet air temperature sensor 29, and the rotational speed Ne detected by the engine rotational speed sensor 30 are inputted via the A/D.

In step 103, calculations shown in FIG. 4 are performed. In step 300, the heating rate by the heater 16 is determined by the temperature difference (
Tdu-Te), and according to the characteristics shown in the figure, the allowable value of Tduo rise per unit time TdL1. decide. In step 301, similarly to step 30Q, a permissible value of the rise in the target temperature Tea of the evaporator outlet air per unit time is determined according to the characteristics shown in the figure. Step 3
In step 02, Tea is determined based on the characteristics shown in the figure based on Ta received in step 101 and information on the position of the intake door 8.

Returning to FIG. 2, in step 104, it is determined according to the flowchart of FIG. 5 whether to perform fixed control on the maximum capacity side for rapid cooling or normal control which is controlled according to the load. In step 400, it is determined whether a flag Fc defined in the RAM indicating that rapid cooling is in progress is set, that is, 1. If true, in step 401, T
du is below target value. Determine whether it has become colder than 0.

If false, the process proceeds to step 4028, where it is determined whether T'duo is lower than the level T du c that requires rapid cooling control. If false, in step 403, the flag F is cleared, that is, set to 0, and the flag Fs indicating the end of rapid cooling control is set to 1.

If the result in step 400 is false, proceed to step 404;
It is determined whether the flag Fs is 1, and if true, the flag F is set in step 405. Set to O.

Returning to FIG. 2, in step 105, it is determined whether the flag Fc is 1. If true, in step 106, the target energizing current Is of the control valve coil 32 is determined. ,. is set to OA, maximum capacity side fixed state. On the other hand, in step 107, control shown in FIG. 6 is performed.

In step 500, the possibility of freezing of the evaporator 12 is determined based on the temperature difference (T e o T e ), and in step 50
1, branch.

In step 502, the need for cooling is determined by the temperature difference (Tdu).
o Tdu), and if T a u is low temperature,
In step 503, Ta control is determined, and in step 50
In step 4, the flag F indicating Te control is set to O.

In step 501, if the determination is true, step 505
Then, set flag F to 1.

In step 506, it is determined whether the flag F is 1, and if it is 1, in step 507, the Te control is set to 0.
In this case, Ta control is performed in step 508. Details of each control are shown in FIGS. 7 and 8.

The flow shown in FIG. 7 will be explained. In step 600, it is determined whether the flag F was 1 last time. Step 6
At 01, it is determined whether Tea has risen above the current 8-mouth air target temperature Tear. If true, in step 602, it is determined whether a flag Fe indicating the execution time of the Tea increase restriction process is 1 or not. Note that the flag Fe is set in the flow of FIG. 3, TIMER, which will be described later.

In step 603, the flag Fe is set to O, and in step 6
At 04, the temperature difference (Tea Teai) is the upper limit value Team
Determine whether it exceeds or not. In step 605,
The increased amount is set as Team and a new Teor, and in step 606, Tea is set as a new T e o i.

If the result in step 601 is false, the flag Fe is set to O in step 607 and the process proceeds to step 606.

If the result in step 600 is false, the flag Fe is set to O in step 608. In step 609, it is determined whether Tea has risen above the current outlet air temperature T8. If true, in step 610, the temperature difference (Teo
Te) is higher than the upper limit T e o m. In step 611, the increase is T e o m
as a new ``'feat''.

In step 612, it is determined whether a flag F indicating the execution time of the integral process is 1. If true, the flag F+ is set to O in step 613. Step 61
4, the temperature difference (Teoi Te) is multiplied by the coefficient /T and added to the integral term I+.

In step 615, the integral term ■1 is set to the upper limit I LmaX
If true, step 61
6, replace 11 with I LmaX.

In step 617, the integral term ■1 is set to the lower limit value I1ain
If true, step 618
Then, replace ■1 with I 1m1n.

In step 619, the temperature difference (T e o t T
e) by the coefficient K and the integral term 1 is added to obtain the energizing current Is of the control valve coil 32. , decide.

The details of Ta control will be explained with reference to FIG. Step 7
00, it is determined whether the flag F was 1 last time. In step 701, it is determined whether Tduo is higher than the current vent outlet target temperature Tduo.

If true, in step 702 it is determined whether a flag F indicating the execution time of the TdLlo increase restriction process is 1 or not. Note that the flag Fd is set in the flow of FIG. 3, TIMER, which will be described later.

In step 703, the flag Fd is set to O, and the chip 7
At 04, the temperature difference (Tduo - Tduo is the upper limit T d
Determine whether it exceeds u Om. Step 705
Now, let's set the increase as T duo+a and create a new Luoz
In step 706, Tduo is changed to a new Tduo.
Let it be z.

If the result in step 701 is false, the flag Fa is set to O in step 707 and the process proceeds to step 706.

If the result in step 700 is false, the flag F is set to O in step 708. In step 709, it is determined whether Tduo has risen above the current vent blowout temperature Tdu. If true, in step 710, the temperature difference (
Tduo-Tdu) is higher than the upper limit T du Om. In step 711, the increase is T
Duom is a new T++uot.

In step 712, it is determined whether the flag F1 indicating the execution time of the integral process is 1. If true, the flag F+ is set to 0 in step 713. Step 71
4, the temperature difference (TduofTdu) is multiplied by a coefficient /T and added to the integral term It.

In step 715, the integral term is the upper limit I l+aa
Determine whether it exceeds X, and if true, step 7
16, replace ■1 with IImaX.

In step 717, the integral term ■1 is the lower limit value I 1mLn
If true, step 71
8, replace ■ with I l+aln.

In step 719, the temperature difference (Tduoi-Tdu) is multiplied by a coefficient K, an integral term is added, and the control valve coil 32
The energizing current I son is determined.

Returning to FIG. 2, step 108 is the main part of the invention.
Proceed to. FIG. 9 shows the details.

In step 800, the necessity of idle stabilization processing is determined based on the detected value Ne of the engine speed sensor 30 based on the characteristic shown in FIG. If necessary, the flag F11 is set to 1, and the process proceeds to step 802 after passing through the determination in step 801. Here, Fn of 1 means a range of Ne where vibration becomes a problem depending on the discharge capacity of the compressor 3 (1000 [rp
m co), that is, within the first predetermined range.

In step 802, a physical quantity related to the heat load of the evaporator 12 is obtained as the product of the inlet air temperature Te and the voltage Vll of the motor 9, and ImaXU
seek. This is the fifth invention. Since the engine rotational speed N6 is within the first predetermined range as determined in steps 800 and 801, the boundary control current I 5 ozU at which the discharge capacity falls within the second predetermined range is determined from the physical quantity related to the thermal load. In step 803, Isa determined in step 106 or step 107
t is Is. Determine whether it is larger than 1U. If true, it is a small capacity where vibration is a problem, ie, outside the second predetermined range, and on the other hand, if I soa is lowered below IsogU and the capacity is increased, it will freeze. Therefore, in step 804, which is the sixth invention, the magnetic clutch 31 is turned off, and in step 805, I sat is set to the maximum current I sotmax. Since the required cooling power is small, insufficient cooling power due to stopping the compressor 3 does not pose a problem.

In step 806, depending on the heat load of the evaporator 12, I
Find so-L. In step 807, I s
Ol is the engineer. , it is determined whether the value is greater than or equal to L. If true,
Assuming that it is within the second predetermined range, in step 808, a flag that allows the magnetic clutch 31 to be turned on is stored in the RAM.

In step 809, the large capacity where vibration is a problem, that is, outside the second predetermined range, and the ImaX
Decrease I sot to U, and in step 810, I s
ow, it is determined whether it is possible to turn on the magnetic clutch 31.

In other words, l5otU is the upper limit of I sot, I5O
1 saX and if the discharge capacity cannot be reduced, the compressor 3 is turned off to prevent vibration from occurring.

Returning to FIG. 2, the process proceeds to step 109. FIG. 10 shows the details.

In step 900, it is determined whether the determination in step 108 is on or not using a flag stored in the RAM. In step 901, due to the temperature difference (Teoz-Te),
The possibility of freezing is determined, and in step 902, the process branches depending on the result.

In step 903, the wind speed GJ detected by the wind speed sensor 27 is calculated based on the voltage V of the air outlet and the motor 9. In step 904, the presence or absence of freezing is determined based on the wind speed difference (G-GJ), and in step 905, the process branches depending on the result.

In step 906, the magnetic clutch 31 is turned on and the current of the control valve coil 32 is set to P soL.
Controlled by WM output.

In step 907, the magnetic clutch 31 is turned off, and in step 908, the current of the control valve coil 32 reaches the maximum I.
It is controlled by PWM output so that it becomes SMmaX.

Next, the TIMER processing will be explained with reference to FIG. In step 150, the execution period of the integral process (in this embodiment,
500 milliseconds) Counter C installed in RAM
Count and amp 1. In step 151, the counter C1 is set to a number C8° corresponding to the execution cycle (in this embodiment,
100=50015). If true, the flag F is set to 1 and the counter C1 is returned to 0 in step 152.

In step 153, a counter Ca that counts the execution cycle of the Tduo increase restriction process is incremented.

In step 154, it is determined whether the counter C4 has reached the number Cao corresponding to the execution cycle. If true,
At step 155, the flag F is set to 1, and the counter C4 is set to 1.
Return to 0.

In step 156, a counter Ce that counts the execution cycle of the Tea increase restriction process is counted and amplified. In step 157, the counter Ce is set to a number C corresponding to the execution cycle.
Determine whether it has become eo. If true, the flag Fe is set to 1 and the counter Ce is returned to O in step 158.

When the above processing is completed, the process returns to the flow shown in FIG. 2 and restarts the process from the next step where the timer interrupt occurred.

According to this embodiment, when the rotational speed of the prime mover is within the first predetermined range where vibrations of the compressor may occur,
Since the discharge capacity of the compressor is set to a balanced second predetermined range or the compressor 3 is stopped, it is possible to prevent the occurrence of vibrations, which has the effect of preventing discomfort to the occupants. .

The second invention is a case where the idle stabilization process at step 108 in FIG. 2 follows the flow shown in FIG. 11.

In step 850, similar to step 802 in FIG. Accordingly, I 5 oil is determined.

In step 851, it is determined whether I sat determined in step 106 or step 107 is greater than l5otU. If true, the vibration is a problem at a small volume, i.e. outside the second predetermined range, and step 8
Proceed to step 55.

In step 852, similar to step 806 in FIG. 9, 5ozL is determined according to the heat load of the evaporator 12.

In step 853, Is. , is greater than or equal to I sat L. If true, it is determined that it is within the second predetermined range, and in step 854, the flag Fv that requires correction of the engine rotational speed is cleared and set to O. Also, step 8
At step 55, the flag Fv is set to 1.

The flag F provides a signal of 0°1 to the engine control electronic control unit 5 via a transmission path 35 indicated by a broken line in FIG. When the engine control electronic control device 5 receives the signal 1, the engine rotation speed Ne is controlled to be outside the first predetermined range, thereby preventing vibrations of the compressor 3.

In the third invention and the fourth invention, the engine control electronic control device 5 receives Ne input from the engine rotation speed sensor 3o.
Then, a determination corresponding to step 800 in FIG. 9 is made, and the first
It is applied to the compressor electronic control device 4 via a transmission path 36 indicated by a broken line in the figure. In this case, in the processing of the compressor electronic control device 4, step 800 in FIG. 9 is eliminated, and step 801 becomes a signal determination of the transmission path 36.

In the above embodiment, the discharge capacity of the compressor 3 was determined from the heat load of the evaporator 12 as in steps 802 and 806 in FIG. The process of step 108 may be performed as shown in FIG. Here, the 2-stroke sensor 37 is based on the service manual structure line E-
The differential transformer type stroke sensor described in CB5 type, pages 1-10 to 13 of issue 89-10 is well known.

Steps 800 and 801 are the same processes as in FIG. 9, and the detection value S of the stroke sensor 37 input in step 102 of FIG. Therefore, when the magnetic clutch 31 is to be turned off, steps 804 and 805 are executed.

In step 861, S is the upper limit value S of the second predetermined range.
It is determined whether it is larger than tU, and if false, it is determined that it is within the second predetermined range and the process proceeds to step 808. Step 862
Then, the current I sow of the control valve coil 32 is corrected based on the difference in discharge volume (St-5tU) so that the discharge volume decreases and falls within the second predetermined range, and the process proceeds to step 810.

〔Effect of the invention〕

According to the present invention, when the rotational speed of the prime mover is within the first predetermined range that may cause vibrations in the compressor, the discharge capacity of the compressor is adjusted to a balanced second predetermined range. Otherwise, the compressor is stopped, which prevents the compressor from vibrating and does not cause discomfort to the occupants.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an automotive air conditioner according to an embodiment of the present invention, and FIGS. 2 to 12 are flowcharts of data stored in the ROM of the microcomputer shown in FIG. 3... Compressor, 4... Electronic control device for compressor, 5. Electronic control device for carrot control, 9... Motor, 12...
- Evaporator, 31... Magnetic clutch, 32... Control valve coil, 37... Stroke sensor.

Claims (1)

[Claims] 1. A prime mover of an automobile, a rotation speed detection means for the prime mover, a compressor with variable discharge capacity using the prime mover as a power source, a control device for the discharge capacity of the compressor, and an evaporator for cooling intake air with a refrigerant circulated by the compressor. In the air conditioner for an automobile including a device, means for detecting a physical quantity related to the discharge capacity of the compressor and a means for detecting a physical quantity related to the heat load of the evaporator are provided, and the discharge capacity control device is configured to detect the physical quantity related to the heat load. means for determining a physical quantity related to a predetermined discharge capacity, and limiting the discharge capacity of the compressor to a second predetermined range smaller than the predetermined discharge capacity when the rotation speed of the prime mover is within a first predetermined range. An air conditioner for an automobile characterized by: