JPS61215140A - Outside temperature display unit for vehicles - Google Patents

Abstract

PURPOSE:To make a device display the actual temperature of right fresh air, by making display renewal so as to be prohibited at a time when a fact that an outside temperature sensor is in a state of being subject to radiation of heat out of an internal-combustion engine is predicted. CONSTITUTION:When temperature of cooling water in a cooling system of an internal-combustion engine is higher than the specified temperature value and driving speed of a car is lower than the specified low-speed value, a discriminating device 6 generates a discrimination signal in cooperation with a cooling water temperature detecting device 4 and a driving speed detecting device 5. With this signal generation, an operational device 2 generates and holds the display output signal so far generated just before generation of this discriminating signal as it is, and a displaying device 3 continues to display the display contents in keeping them intact on the basis of a suchlike display output signal. Therefore, if an outside temperature detecting device 1 receives radiation of heat out of the internal-combustion engine and fails to rightly detect the outside temperature, the display contents of the displaying device 3 are able to display the actual temperature of almost rightly fresh air.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a display device for a vehicle, and more particularly to an outside temperature display device for a vehicle suitable for detecting the temperature of the outside air of a vehicle and displaying the detection result.

[Prior art]

□ Conventionally, this type of outside temperature display device uses an outside temperature sensor installed in a part of the vehicle at a location where it is affected by the heat radiation energy of the internal combustion engine mounted on the vehicle. There is a sensor that detects the temperature of the outside air at the location where the sensor is installed.

[Problem that the invention seeks to solve]

However, in such a configuration, although the outside temperature sensor is installed in a position where it is unlikely to receive direct sunlight, outside airflow, etc., the outside temperature sensor receives heat radiated from the internal combustion engine body and is exposed to outside air. The actual temperature of the outside air may not be detected correctly, and therefore the temperature of the outside air may be displayed. Furthermore, this problem was particularly noticeable when the internal combustion engine was operating when the vehicle was stopped or running at low speed.

The present invention is designed to deal with this problem (in an outside temperature display device for a vehicle, the display is not updated when the outside temperature sensor is predicted to be in a state where it is likely to receive heat radiated from the internal combustion engine). This is what we are trying to do.

[Means for solving problems]

In solving this problem, the structural features of the present invention are as follows:
As illustrated in Fig. 1, the external air temperature sensor is installed in a part of the vehicle at a location where it is affected by the heat radiation energy of the internal combustion engine mounted on the vehicle, and detects the temperature of the outside air and generates an outside temperature detection signal. temperature detection means 1; calculation means 2 for calculating the temperature of the outside air according to the value of the outside temperature detection signal and generating this as a display output signal; and 3) a lever display output signal responsive to the display output signal. A display means 3 for displaying the value of as the temperature of the outside air; a cooling water temperature detecting means 4 for detecting the temperature of the cooling water in the cooling system of the internal combustion engine and generating a cooling water temperature detection signal; , a traveling speed detecting means 5 that detects the traveling speed of the vehicle and generates a traveling speed detection signal; and a traveling speed detecting means 5 that detects the traveling speed of the vehicle and generates a traveling speed detection signal; Discrimination means 6 for generating a discrimination signal when the value of the traveling speed detection signal is smaller than a predetermined low speed value, and holding means 7 for maintaining the application of the display output signal immediately before the generation of this signal in response to the discrimination signal are provided. That's what I did.

[Effect]

Therefore, by configuring the present invention in this way, even if the outside temperature detection means 1 is disposed at a position where it can easily receive heat radiated from the internal combustion engine, the temperature of the cooling water in the cooling system of the internal combustion engine will be low. When the temperature is higher than the predetermined temperature value and the running speed of the vehicle is lower than the predetermined low speed value, the discriminating means 6 generates a discriminating signal in cooperation with the cooling water temperature detecting means 4 and the running speed detecting means 5. The calculation means 2, in cooperation with the holding means 7, generates and holds the display output signal generated immediately before the generation of the discrimination signal, and the display means 3 displays the display contents as they are based on the display output signal. Therefore, even if the outside temperature detecting means 1 cannot correctly detect the temperature of the outside air due to heat radiation from the internal combustion engine, the display contents of the display means 3 can display the actual temperature of the outside air which is almost correct.

〔Example〕

Hereinafter, one embodiment of the present invention will be explained with reference to the drawings.
The figure shows an example of an outside temperature display device according to the present invention that is used in a vehicle, and this outside temperature display device includes an outside temperature sensor 10a, a cooling water temperature sensor 10b, and a running speed sensor I.
OC, each of these sensors] each A-D converter 20a, 20b and waveform shaper 20C connected to Oa, Job, and 10C, and each of these A-D converters 20a, 20b
, a microcomputer 30 connected to the waveform shaper 20C, a drive circuit 40 connected to the microcomputer 30, and a display 50 connected to the drive circuit 40.・The outside temperature sensor 10a is
It is disposed in a part of the vehicle at a position in front of the rear end of the main body of the internal combustion engine mounted on the vehicle in a position where it is difficult to receive outside airflow and direct sunlight. The outside air temperature sensor lOa detects the outside air temperature Ta near its installation position and generates an analog outside air temperature detection signal at a level corresponding to this. The cooling water temperature sensor 10b detects the temperature Tw of the cooling water in the cooling system of the internal combustion engine, and generates an analog cooling water temperature detection signal at a level corresponding to the temperature Tw.

The running speed sensor 10C detects the running speed Vs of the vehicle and generates a series of pulse signals at a frequency proportional to this.

The A-, D converter 20a digitally converts the level of the analog outside temperature detection signal from the outside temperature sensor Oa, and generates this digital conversion value (hereinafter referred to as digital outside temperature value Ta) as a digital outside temperature signal. The A-D converter 20b digitally converts the level of the analog coolant temperature detection signal from the coolant temperature sensor 10b, and generates this digital conversion value (hereinafter referred to as digital coolant temperature value TW) as a digital coolant temperature signal. Waveform shaper 2
0c is a running speed sensor], each pulse signal from Oc is sequentially waveform-shaped and generated as a shaped signal.

The microcomputer 30 executes the display control program stored in advance in the flow chart 1 shown in FIG.
Accordingly, both A-D converters 20a, 20b and waveform shaper 2
It is repeatedly executed in cooperation with 0c, and during the repetition of the execution, various arithmetic operations necessary for controlling the drive circuit 40 connected to the display 50 are performed as described below.

In this embodiment configured as described above, when the vehicle is operated by operating its ignition switch to start the Ml engine and put it into a running state, and also put the microcomputer 30 into an operating state, the microcomputer 30
starts execution of the display control program in step 60 according to flowchart 1- in FIG. 3, and in step 61,
The running speed Vs of the vehicle is calculated based on a series of shaping signals generated by the waveform shaper 20c in cooperation with the running speed]Oc. If the warm-up of the internal combustion engine has not been completed at this stage, the microcomputer 30 in step 62 reads the information from the A-D converter 20b to the cooling water temperature sensor 10.
Based on the fact that the value TW of the digital water temperature signal generated by the cooperation with b is smaller than the predetermined digital temperature value TWO,
NO”, and in step 65, the A-D converter 20
The temperature Ta of the outside air is calculated based on the value of the digital outside air temperature signal generated by cooperation with the outside air temperature sensor 10a from a, and this is generated as a display output signal. However, the predetermined digital temperature value 'p w o is stored in advance in the microcomputer 30 as a cooling water temperature TW that is somewhat lower than the warm-up end temperature of the internal combustion engine.

As described above, when a display output signal is generated from the microcomputer 30, the drive circuit 40 generates the value of the display output signal as a drive signal, and in response, the display 50 outputs the value of the drive signal, that is, the value of the outside air. Displays temperature Ta. In this case, since the internal combustion engine has not yet been warmed up, the amount of heat radiated from the main body of the internal combustion engine is negligible. Therefore,
Since the outside air temperature sensor loa correctly detects the temperature of the outside air of the vehicle without being affected by heat radiation from the main body of the inner Ml, it is possible to detect the actual outside air temperature Ta based on the display contents of the display 50. Can be recognized correctly.

After that, when the internal combustion engine is warmed up, the A-D converter 2
When the value Tw of the digital cooling water temperature signal from 0b exceeds the predetermined digital temperature value Tw,oId, the microcomputer 30 determines "YESJ" in step 62. If is greater than or equal to the predetermined low speed value VsO, the microcomputer 30 determines rYEsJ in step 63, and generates a display output signal in the same manner as described above in step 65.However, the predetermined low speed value Vso is set when Vs≧VSO. The temperature is selected so as to be able to sufficiently absorb the heat radiated from the main body of the internal combustion engine upon completion of warm-up by the external airflow generated when the engine is warmed up, and is stored in advance in the microcomputer 30.

As described above, when a display output signal is generated from the microcomputer 30, the drive circuit 40 generates the value of the display output signal as a drive signal, and in response, the display 50 outputs the value of the drive signal, that is, the value of the outside air. Displays temperature Ta. In such a case, although the internal combustion engine radiates heat from its main body at a high temperature after warming up, this radiated energy is absorbed by the outside airflow generated by the running of the vehicle based on Vs≧Vso. Therefore, the outside temperature sensor 10
a accurately detects the temperature of the outside air itself of the vehicle without being influenced by the main body of the internal combustion engine, so the temperature Ta of the outside air can be correctly recognized based on the display content of the display 50.

In such a state, if the determination in step 63 becomes "NO" due to a decrease in the traveling speed of the vehicle, the microcomputer 30 in step 66
The display output signal in step 65 immediately before the determination with rNOj in step 65 is maintained as it is. As a result, the display device 50, in cooperation with the drive circuit 40, continues to display the display content immediately before the rNOJ determination in step 63. In such a case, the outside temperature sensor 10a receives high-temperature heat radiated from the main body of the internal combustion engine at the end of warm-up when Vs<Vso, and detects the actual temperature T of the outside air.
Even if the outside temperature sensor 10a cannot be detected correctly, the display content on the display 50 will be the outside temperature sensor 10a immediately before this erroneous detection, regardless of this erroneous detection by the outside temperature sensor 10a.
In order to maintain a value corresponding to an appropriate detection result, the temperature of the outside air will not be recognized incorrectly from the display contents of the display 50.

[Brief explanation of drawings]

FIG. 1 is a diagram corresponding to the configuration of the invention described in the claims, FIG. 2 is a block diagram showing an embodiment of the invention,
3 is a flowchart showing the operation of the microcomputer shown in FIG. 2. Explanation of symbols 10a...Outside temperature sensor, 10b...Cooling water temperature sensor, 10C...Outside temperature sensor, 20a. 20b... A-D converter, 20C... Traveling speed sensor, 30... Microcomputer, 40... Drive circuit, 50... Display device.

Claims (1)

[Claims] an outside temperature detection means disposed in a part of the vehicle at a position affected by heat radiation energy of an internal combustion engine mounted on the vehicle to detect the temperature of outside air and generate an outside temperature detection signal; and the outside temperature detection means. a calculation means for calculating the temperature of the outside air according to the value of the signal and generating it as a display output signal; and a display means for displaying the value of the display output signal as the temperature of the outside air in response to the display output signal. The outside temperature display device includes: a cooling water temperature detection means that detects the temperature of the cooling water in the cooling system of the internal combustion engine and generates a cooling water temperature detection signal; and a cooling water temperature detection means that detects the running speed of the vehicle and generates a running speed detection signal. speed detecting means; generating a determination signal when the value of the cooling water temperature detection signal is greater than a predetermined temperature value determined in relation to the warm-up end temperature of the internal combustion engine and the value of the traveling speed detection signal is smaller than a predetermined low speed value; Discrimination means;
An outside temperature display device for a vehicle, further comprising a holding means for maintaining the display output signal applied immediately before the signal is generated in response to the discrimination signal.