JPH0121003B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to an air conditioning control device for an automobile having an abnormality diagnosis function of sensor input. [Prior Art] As the functions of automotive air conditioning control devices become more complex in order to achieve a more suitable interior environment, these control devices are also equipped with microcomputers and other devices, as well as temperature sensors and other sensors. The structure has become such that the damper opening degree, air volume, etc. are controlled by inputting control-related information from the means and making precise condition judgments. [Problems to be Solved by the Invention] As these control devices that control the interior environment of vehicles, that is, automotive air conditioning control devices, become more sophisticated and complex, it becomes difficult to determine the internal operating state using input/output signals from the outside alone. It has become very difficult to check in detail, and a problem has arisen in that special large-scale inspection equipment must be used to analyze the internal operating state of the air conditioner, especially when an abnormality occurs. However, there are problems in that it is extremely difficult to install large inspection equipment at many automobile service shops scattered throughout the country, and it is also impractical to bring such large equipment into the interior of a car for inspection. Ta. Furthermore, even if large-scale inspection equipment is used,
Since the control state of each actuator changes in response to ever-changing operating conditions even in the event of a failure, there is a drawback that the symptoms at the time of abnormality cannot be maintained as they are. On the other hand, it is possible to consider a method of switching the control state of each actuator to preset control conditions in the event of a failure, but this method has the problem of being impractical as the control becomes far removed from the operating conditions. . [Means for Solving the Problems] In order to solve the above problems, the configuration adopted by the present invention is as illustrated in FIG. The control device includes input means _M3 for inputting signals from a setting device _M1 for setting air conditioning conditions and various sensors _M2 for detecting air conditioning conditions, and a desired air conditioning condition based on the input signals from the input means. An air conditioning control device for a vehicle, comprising: an air conditioning control means _M4 that performs control to generate the air conditioner _; The air conditioning control means _M4 further includes _a detection means _M41 for detecting abnormal states of the various sensors.
a storage means _M42 for storing abnormal states of the various sensors _M2 detected by the detection means M41; and a storage means _M42 for storing abnormal states of the various sensors _M2 detected by the detection means M41; notification control means for outputting a notification control signal that causes the notification means _M6 to distinguish and notify the abnormality stored in the storage means _M42 and the currently continuing abnormality when the abnormality is stored in the storage means M42;
Adopt the technical means of equipping with M ₄₃ . [Function] According to the automotive air conditioning control device having the control variable display function of the present invention having the above-described configuration, in normal air conditioning control, the air conditioning conditions are input from the setting device _M1 , and on the other hand,
Input means for air conditioning status from various sensors _M2
This is input to the air conditioning control means _M4 via _M3 , and based on this, the air conditioning control means _M3 performs control to achieve a desired air conditioning state. In this case, if there is an abnormality in the sensor _M2 , the detection means _M41 determines the abnormal state, and the detected abnormal state is stored in the storage means _M42 . Next, the air conditioning control means _M4 is controlled by the switching means _M5 .
When switched to the sensor diagnosis mode, the notification control means _M43 distinguishes between the abnormal state stored in the past in the storage means _M42 and the abnormal state that is currently continuously occurring in the sensor _M2 . Control is performed so that notification is provided by the notification means _M6 . [Embodiment] Hereinafter, an embodiment in which the present invention is applied to an automotive air conditioning control device of a generally widely used cold air/warm air mixing method will be described with reference to the drawings. First, Fig. 2 shows the entire air conditioning system, in which an outside air inlet 2 and inside air inlets 3a, 3b are provided on the upstream side of a ventilation duct 1, and ventilation is controlled by opening and closing inside/outside air switching dampers 4a, 4b. Outside air or inside air is selectively drawn into the duct 1. The inside/outside air switching dampers 4a, 4b are opened and closed by diaphragm actuators 6a, 6b controlled by solenoid valves 5a, 5b. Reference numeral 7 denotes an electric blower (blower motor) installed in the ventilation duct 1, which blows sucked air to the downstream side of the ventilation duct 1. The refrigeration cycle uses a refrigerant evaporator (evaporator)
8, an expansion valve 9, a liquid receiver 10, a condenser 11, and a compressor 14, which are driven by an automobile engine 13 via an electromagnetic clutch 12, and are connected to a ventilation duct by the refrigerant evaporator 8. The air passing through 1 is cooled. A heater core 15 uses the cooling water of the engine 13 as a heat source, and is provided in series downstream of the refrigerant evaporator 8 in the ventilation duct 1, and is controlled by a solenoid valve (water valve) 16. Reference numeral 17 denotes a temperature adjustment damper (air mix damper), which is installed at the front of the heater 15 and controls the ratio of the amount of air passing through the heater 15 and being heated to the amount of low-temperature air passing through the bias passage 18. The blowout temperature can be adjusted by adjusting the temperature, and the opening degree of the temperature adjustment damper 17 is adjusted by a diaphragm actuator 19. 20 is a negative pressure regulator that adjusts the negative pressure supplied to the diaphragm actuator 19, and has two built-in solenoid valves 21 and 22;
1 and 22 to open and close a negative pressure pipe 23 and an atmosphere opening port 24, respectively, and the negative pressure pipe 23 is configured to receive the intake negative pressure of the engine 13,
Further, the opening degree of the temperature adjusting damper 17 can be detected by a potentiometer _TTP . Reference numeral 26 indicates a heating outlet, which blows warm air to the passenger's feet in the vehicle interior, 27 indicates a differential outlet, which blows warm air toward the front window glass, and 28 indicates a cooling outlet, which blows warm air to the passenger's feet in the vehicle interior. It blows out cold air toward the upper body, and each outlet is switched by blowout mode switching dampers 29, 30, and 31. Of these, 29 is a heating switching damper, which is operated by a diaphragm controlled by a solenoid valve 32. opened and closed by the container 33,
0 and 31 are differential and cooling switching dampers, and solenoid valve 3
It is opened and closed by a diaphragm actuator 35 controlled by 4. Next, FIG. 3 is a block diagram of a control circuit, in which a microcomputer 36 receives various information signals,
Based on this, processing such as calculation is performed according to a preset control program, and various actuators of the air conditioning system, that is, solenoid valves 5a, 5b, 1
It electrically commands the operations of the air conditioners 6, 21, 22, 32, 34, etc., and controls the entire air conditioner, and is composed of the following parts. Reference numeral 37 denotes a panel switch for switching various operation modes, and is provided on the display panel 71 shown in FIG. 38 is a selector for selecting the input of the panel switch 37; 39 is an internal air sensor S _TR , an outside air sensor S _TAM , a solar radiation sensor S _ST , an after-evaporation sensor S _TE , a water temperature sensor S _TW , a potentiometer S _TP 25, etc. An analog switch 41 selects each input signal from the sensor 40, and 41 is the analog switch 39.
42 is a central processing unit (hereinafter referred to as CPU) with a built-in control program, 43
is a CPU with a built-in output signal control program,
44 is a set temperature indicator that displays the set temperature;
45 is a lamp driver that drives the mode display lamp 46; 47 is various actuators 48, that is, the electromagnetic valves 5a, 5b, 16, 21, 22, 3;
2, 34 and heater relay and MgC not shown
actuator driver that drives relays,
49 is a blower motor driver that drives the blower motor 50; 51 is a lock detection circuit for the blower motor 50; 52 is a buzzer that sounds when a valid input is received from the panel switch 37; 53 is a backup and reset signal control circuit; It is a constant voltage power supply circuit and is connected to the battery 55 via the engine's ignition switch. Further, a diagnostic signal line 56 connected to the accessory terminal A _CC of the ignition switch section S ₁ is connected to the CPU 42, and the mode display lamp 46 is used to control night lighting and dimming. A lighting dimming circuit 57 is connected. FIG. 4 shows an example of the display panel 71.
44 is a set temperature display which displays the set temperature in the normal operation mode and an error code in the abnormality display mode.In the normal operation mode, the setting switch 710 (for increasing),
By operating 720 (for lowering), the desired set temperature is displayed. Further, on the display panel, 711 and 712 are switches for setting the inside air circulation mode and the outside air introduction mode, respectively. Reference numeral 72 denotes an automatic control switch that automatically controls the opening degree of the temperature control damper 17 so that the air conditioner reaches the set temperature. 73 is a switch for stopping the blower 7 and the compressor. 74 and 75 are switches for adjusting the air volume of the blower 7 to low and high, respectively. A switch 76 reduces the operating rate of the compressor 14 by varying the discharge capacity of the compressor 14. Reference numeral 77 is an air conditioner switch for turning on the electromagnetic clutch 12 and operating the compressor 14. 77, 78, 79, 8
0 and 81 are switches for selecting an air conditioning mode, which are a vent switch 78, a bay level switch 79, a heater switch 80, and a defroster switch 81, respectively. The display panel 71 also functions as a switching means for switching the control mode of the microcomputer 36 between normal air conditioning control and sensor diagnostic control mode. That is, when the ignition switch is switched to the accessory position A _CC shown in Figure 3,
When the automatic control switch 72 and the defroster switch 81 of the panel switches 37 are simultaneously turned on, the microcomputer 36 switches to sensor diagnostic control. Furthermore, when the "OFF" switch 73 is turned on during sensor diagnostic control, normal control is returned to. The display panel 71 is provided with a buzzer 81 that sounds when a switch is received in the normal operation mode, and that sounds when a current failure occurs in the abnormality display mode. Next, the specific operation of this embodiment having the above configuration will be explained. FIG. 5 is a flowchart representing the control program, and the processing represented in each step will be explained below. 100 represents a step in which a reset signal is given to the CPUs 42 and 43 when the power is turned on to switch the IG switch to the A _CC position or the ON position, and the execution of the program is started. 101 represents the step of turning off the output of each lamp and actuator, restoring backup data such as set temperature, and performing initial settings such as setting built-in timers in the CPUs 42 and 43. 102 represents a step for determining whether the panel switch 37 is in abnormal display mode or normal operation mode based on the state of the panel switch 37;
“AUTO” switch 72 and defroster switch 8
If both 1 and 1 are turned on at the same time, the mode shifts to diagnostic control, and if they are not turned on, the normal operation mode is entered. 103 is step 102
When the normal operation mode is determined, the input of the panel switch 37 is read through the selector 38, update of the set temperature and automatic/manual control are determined, and when a valid switch input is received, the buzzer 52 sounds. Represents a step. 104 is the sensor 40 for automatic control calculation.
This represents the step of inputting the value after A/D conversion through the analog switch 39 and the A/D converter 41. Reference numeral 105 represents a step for determining whether the sensor is open or short based on the A/D conversion value input in step 104, and storing it if an abnormality is observed for a predetermined period of time. 106 to 110 represent steps for calculating control outputs based on the information input in steps 103 and 104. Here, the control variable values to be displayed are inside temperature (TR), outside temperature (TAM), solar radiation (ST), evaporator temperature (TE), radiator water temperature (TW), required air temperature (TAO), and temperature adjustment damper. These include opening degree (SW), blower air volume (BWR), and output of various actuators. Furthermore, K _SET , K _R , K _AM , K _S , and K _C in step 106 each represent a predetermined constant. Also, (TR), (TAM), (TE), (TW), (ST)
The internal calculations of the computer use 8-bit binary numbers, for example, the value "00" is (TR),
-1.75℃ for (TAM), (TE), (TW)
In (ST), the solar radiation is 22.5℃, and in (ST), the solar radiation is "0". Further, (TAO) uses a 16-bit binary number, and for example, the value "4000" corresponds to 0°C. (SW) uses an 8-bit binary number, for example, the value "29" corresponds to 0%, and (BWR) uses a 4-bit binary number to represent the air volume level. 111 represents a step for displaying the calculation result in step 110 on the mode display lamp 46 and the set temperature display 44. 112 represents a step in which control signals for each actuator 48 and blower motor 50 are output based on the calculation results in step 111. 113 is step 102, when the ignition switch _S1 is in the A _CC position and the automatic control switch 72 and defroster switch 81 are turned on at the same time, if it is determined that the mode is abnormality diagnosis mode, the panel switch 37 is turned on. Represents a step that reads input. 114 represents a step in which the value of the sensor 40 is A/D converted and inputted for the purpose of displaying the current failure status. 115 to 120 represent steps for sequentially displaying past and present failures of six types of sensors. 121 represents a step for displaying that all six types of sensors are normal when there is no abnormality in the past or present. Step 122 is a step for determining whether or not the "OFF" switch 73 of the panel switch 37 is turned on when the above diagnostic mode is being performed.The diagnostic mode is executed unless the "OFF" switch 73 is turned on, and once the switch is When 73 is turned on, the process proceeds to step 103, and the normal operation mode is entered. Therefore, to return to diagnostic mode, it is necessary to turn off the power (IG switch in the OFF position). As shown above, normally the steps start from step 102.
112 normal operation mode, especially step 105
The sensor failure status is memorized. Also, if the abnormality diagnosis mode is specified, steps 113 to 121 are performed.
is executed to distinguish between the past failure status stored in step 105 and the current failure status based on the value input in step 114. FIG. 6 shows a detailed flowchart of step 105 for storing faults. The A/D conversion value TR of the inside temperature sensor is expressed as an 8-bit binary number, with the lower limit value "00" being approximately -20°C and the upper limit value "FF".
(Hexadecimal notation) corresponds to approximately 70℃. During normal operation, it is rare for TR to become ``00'' or ``FF'', so when TR = 00, the inside temperature sensor is considered open, and when TR = FF, the inside temperature sensor is shorted. When this condition continues for approximately 8 minutes and 30 seconds, it is determined that a failure has occurred, and the 1-bit flag for each of TR, S, OLD or TR, O, and OLD is set to 1. Note that these flags are not erased until the power is turned off. Similar processing is performed on the outside temperature sensor _STAM , the post-evaporation sensor _STE , the solar radiation sensor _SST , the water temperature sensor _STW , and the A/M sensor.
Performed on damper potentiometer S _TP . 7 to 12 show specific flowcharts of steps 115 to 120 in FIG. 5, respectively.
Therefore, as an example, the case of the inside temperature sensor _STR shown in FIG. 7 will be explained. Steps 200 to 205 perform display processing regarding the TR open failure. Step 201 is a step for determining whether the TR is currently open. If it is currently open, the process proceeds to steps 204 and 205 and turns on the buzzer to display an error code "21.0." Step 202 is when TR is not currently open.
Determine whether a failure has occurred in the past. That is, it is determined whether the flags TR, S, and OLD in FIG. 6 are 1. If there is no memory of a malfunction, proceed to step
The process advances to 206, and no display regarding S _TR open is made. If the flag TR・S・OLD=1 and there is memory of a past failure, proceed to steps 203 and 205.
Turn off the buzzer and display the error code "21.0". Therefore, if the abnormality code "21.0" is displayed on the set temperature display 41, it is known that there is an open failure in the internal air sensor, and the ON/OFF of the buzzer indicates whether it is a current failure or a past failure. I can tell.
In addition, in case of a short failure of the internal air sensor, steps 206 to 206 of the same algorithm as steps 201 to 205 above are processed.
It is determined by executing 260. The above explanation is about the inside temperature sensor S _TR , but the outside temperature sensor _STAM , the after-evaporation sensor S _TE that detects the temperature on the downstream side of the evaporator 8, and the solar radiation state entering the vehicle interior. The current and past abnormal states of the solar radiation sensor S _ST , the water temperature sensor S _TW that detects the temperature of the engine cooling water introduced into the heater 15 , and the potentiometer S _TP that detects the opening degree of the temperature adjustment damper 17 are listed in the eighth table. By executing the flowcharts shown in FIGS. Table 1 shows the numerical values displayed on the set temperature display 41 when each sensor is abnormal.

〔Effect of the invention〕

As described above, the present invention makes it possible to distinguish and notify past and present failures when performing failure diagnosis using signals from various sensors that detect air conditioning conditions. This also has the effect of enabling effective maintenance and inspection of any failures that occur.

[Brief explanation of drawings]

The figures show an embodiment of the present invention, and FIG. 1 is a block diagram showing the configuration of the present invention, FIG. 2 is an explanatory diagram showing the entire air conditioner, FIG. 3 is a block diagram of the control circuit, and FIG. The figure is a front view showing an example of a display panel.
This figure is a control flowchart of the microcomputer shown in FIG. 3, and FIGS. 6 to 13 are partial detailed flowcharts of FIG. 5. 1... Ventilation duct, 4a, 4b... Inside/outside air switching damper, 7... Electric blower, 8... Refrigerant evaporator,
14... Compressor, 15... Heater, 17... Temperature adjustment damper, 5a, 5b, 16, 21, 22,
32, 34... Solenoid valve, 36... Microcomputer, 37... Panel switch, 40... Sensor, 42, 43... CPU, 44... Set temperature display, 48... Actuator, 72-80...
Panel switch, S _TR ...Inside air sensor, S _TAM ...
Outside air sensor, S _ST ... Solar radiation sensor, S _TE ... Post-evaporation sensor, S _TW ... Water temperature sensor, S _TP ... Potentiometer.

Claims (1)

[Claims] 1. Input means for inputting signals from a setting device for setting air conditioning conditions and various sensors for detecting air conditioning conditions, and generating a desired air conditioning condition based on the input signals from this input means. An air conditioning control device for a vehicle comprising: an air conditioning control means for controlling the air conditioning; The air conditioning control means further comprises: a detection means for detecting abnormal states of the various sensors; a storage means for storing abnormal states of the various sensors detected by the detection means; When the control means is switched to the sensor diagnosis mode by the switching means, a notification control signal is sent to the notification means to distinguish between the abnormality stored in the storage means and the abnormality that is currently continuing. What is claimed is: 1. An air conditioning control device for a vehicle having a sensor abnormality diagnosis function, comprising: a notification control means for outputting an information. 2. The switching means is configured to put the air conditioning control means into a sensor diagnosis mode by simultaneously turning on a plurality of switches serving as early setting devices for setting air conditioning conditions. A vehicle air conditioning control device having a sensor abnormality diagnosis function according to scope 1. 3. A vehicle having a sensor abnormality diagnosis function according to claim 1, wherein the notification means is configured to display an abnormal state on a set temperature display that displays a set temperature. Air conditioning control equipment.