JPH0833318B2 - Liquid level detector for vehicle - Google Patents

Description

TECHNICAL FIELD The present invention relates to a device for detecting and displaying a liquid level such as oil or coolant of an engine as maintenance information indicating a state of a function involved in traveling of a vehicle. .

<Prior Art> Various types of information display devices for displaying a running state of a vehicle or a state of each part of the vehicle have been conventionally proposed. For example, Japanese Examined Patent Publication No. 51-20787 sets some inspection points necessary for safe running of a vehicle and warns a signal indicating an abnormal state of these points in a predetermined priority order according to the degree of danger. A centralized warning device for a vehicle that is generated as a command signal has been proposed.

In such an information display device, it is desirable to detect and display the liquid level of oil or coolant of the engine as important maintenance information.

However, these fluid levels cannot be accurately detected during engine operation. In addition, it is possible to detect and display the liquid level when the engine is not operating, but especially in the case of engine oil, for example, when the engine is operated and then stopped, it depends on whether or not the engine is warming up. The time when the oil returns to the oil pan is different, and the liquid level may not be accurately detected as in the operating state of the engine. Therefore, even if the output of the liquid level gauge is directly displayed, incorrect information may be transmitted to the driver in some cases.

In particular, if the previous liquid level is abnormal and this time it continues to be abnormal, it is desirable to prompt the driver to replenish the liquid early.

<Problems to be Solved by the Invention> In view of the above-mentioned problems of the prior art, the main object of the present invention is to reliably and quickly determine the liquid level of oil or engine cooling water of a vehicle engine as maintenance information. To provide a device for detecting and displaying.

<Means for Solving the Problems> According to the present invention, such an object is a liquid level detection device as maintenance information in a vehicle engine, in which the cooling water temperature of the engine is a predetermined temperature. Determination means for determining whether or not the liquid level has been reached, timing means for measuring the elapsed time since the engine was stopped or the ignition switch was turned off, and the liquid level is stored if it was abnormal at the previous detection. A memory means, and when it is determined that the cooling water temperature has reached a predetermined temperature, the timer means enables the liquid level to be detected after the engine stops, and then the liquid level is detected. If it is not determined that the cooling water temperature has reached the predetermined temperature, detection of the liquid level is not performed until the second predetermined time, which is longer than the first predetermined time, is measured after the engine is stopped. If the liquid level abnormal state is stored in the memory means, it is possible to detect the liquid level before the elapse of the first predetermined time. It is achieved by

<Action> In this way, considering the state of the engine, the detectable time is divided into the case where the viscosity of the engine oil is high in the engine warm-up completed state and the case where the viscosity is low in the cold state, The cooling water temperature is used to detect the time it takes for the engine oil to return after the engine is stopped, and the time taken to start the liquid level detection is divided into the time when warm-up is completed and the time when cool-down is taken into consideration. The liquid level can be detected at an early stage with high reliability by performing the liquid level detection after returning to step 1 and performing the detection as soon as possible after the completion of warm-up. Further, if the previous liquid level is abnormal, the liquid level can be detected earlier by not detecting whether the engine is cold or warm.
Here, when the liquid level is abnormal last time, it is abnormal also this time if the liquid is not replenished, and it is usually a sufficiently high liquid level if the liquid is replenished.
Therefore, if the liquid level is abnormal at the previous detection, a relatively correct detection result can be obtained even if the liquid level is detected without making the cold / warm determination.

<Embodiment> Hereinafter, the present invention will be described in detail with reference to a specific embodiment with reference to the accompanying drawings.

FIG. 1 shows a dashboard 1 of a vehicle. A center console 2 equipped with audio equipment and the like is provided below the center of the dashboard 1, and an air conditioner 3 and an air conditioning air outlet 4 are provided above the center console 2. An information display device 5, which will be described later, is provided directly above the air outlet 4. In the case of the present embodiment, the driver's seat is provided on the left side in the traveling direction of the vehicle compartment, and accordingly, the steering wheel 7 and the instrument panel 6 are provided on the left side of the information display device 5 or the center console 2.

2 and 3 show the information display device 5 in detail. This display device 5 is composed of a relatively long oblong box, a display portion 12 formed of a fluorescent display tube is provided in the front of the central portion, and relatively large push buttons 13 and 14 are provided on the left and right sides thereof. The lower ends of these push buttons 13 and 14 are coupled to the main body via hinges 15 and 16, and the upper ends of the push buttons 13 and 14 are provided with recesses 17 and 18 for engaging fingers. . The push buttons 13 and 14 can be opened downward by engaging fingers with the recesses 17 and 18. In addition, the protrusions 8 and 9 are provided on the lower portions of the back surfaces of the push buttons 13 and 14, respectively. The protrusions come into contact with the elastic members 10 and 11 on the main body side, so that the push buttons 13 and When the push button 13 or 14 is not fully opened, the push buttons 13 and 14 are normally urged in the closing direction to improve the open / close feeling of the push buttons 13 and 14.

Projections 19 and 20 are provided on the back surface of the push buttons 13 and 14 slightly above, and when the push buttons 13 and 14 are closed, the projections 19 and 20 are formed on the main body. By pressing the switches 21 and 22 provided on the side,
The electric circuit is opened and closed, and the functions of the push buttons 13 and 14 are achieved. Further, as shown in FIG. 3, there are three and four switch keys 23 to 14 on the backside of the push buttons 13 and 14, respectively.
29 are provided.

FIG. 4 is a conceptual diagram showing a procedure for selecting information items displayed on the information display device shown in FIGS. 1 to 3.
The white arrow indicates the operation of pushing the push button 13 for travel information (trip function), and various vehicle travel information such as fuel consumption and remaining fuel amount is displayed. The arrow with hatching indicates the operation of pushing the maintenance information (system check) push button 14. Normally, the time display 30 is displayed on the display unit 12 as shown in FIG. 5, and every time the system check push button 14 is pressed, the displayed contents are the periodic inspection time display 31, the oil change time, and the like. Display 32, oil level display 33, engine cooling water level display 34, washer liquid level display 35, and so on.If the washer liquid level display 35 is displayed, press the system check push button 14 again. Timetable hour 30 is obtained. Further, when the display 31 to 35 is left in a selected state for a certain time, for example, 10 seconds, the time display 30 is automatically displayed. Similarly, when the trip function push button 13 is pressed while these displays 31 to 35 are displayed, the time display 30 is obtained, and when the push button 13 is continuously pressed, the travelable distance / fuel remaining amount is sequentially displayed. Display, trip / timetable time, instantaneous fuel consumption display and average fuel consumption display. When the trip function push button 13 is pressed while the average fuel consumption is displayed, the timetable time 30 is obtained again.

If the system check push button 14 is pressed while these trip function displays are being performed, the time display 30 is obtained.

Next, the display contents of the maintenance information will be described in detail with reference to FIGS.

FIG. 5 shows the normal timetable time 30. As far as this display is concerned, there is no difference from the normal digital clock.

The periodic inspection time display 31 and the oil exchange time display 32 prompt the driver to perform the periodic inspection and oil exchange time in consideration of the traveling distance, and the driver sets the inspection and oil exchange time with the arrow keys 27 and the set key 29. The contents displayed at the time of setting are confirmed by pressing the service reset key 26, and detailed description thereof will be omitted.

Fig. 6 shows the engine oil level in normal condition 33
With the structure as shown in the configuration diagram of FIG. 9, the oil level is detected according to the flow chart of FIG. 10, and the above display is made in the normal state.

As shown in FIG. 9, an ignition switch 42,
An oil level sensor 43 provided in an oil pan (not shown) and a water temperature sensor 44 provided in a cooling water passage (not shown) of the engine are connected to the information display device 5.

The procedure for detecting and displaying the oil level will be described below with reference to the flowchart of FIG. First, in step 51, when an ignition-on signal is input from the ignition switch 44 to the information display device 5, the oil level sensor 43
The oil level is detected by (step 52), and it is determined in step 53 whether the oil level is equal to or higher than a specified value. If it is above the specified value, that is, if the oil level is appropriate, the routine proceeds to step 54, where the oil level display 33 in the normal state shown in FIG. Further, the display 33 is displayed only for 5 minutes from the time when the ignition is turned on, and thereafter, the process proceeds to step 55 and the seventh
A display 33a indicating that the engine oil level shown in the figure cannot be detected and displayed is displayed. On the other hand, if the oil level is lower than the specified oil level in step 53, the process proceeds to step 56 to read the previously displayed contents of the oil level stored in the memory of the information display device 5, and in step 57 the previous display is performed. Is a display 33b (Fig. 8) indicating that the oil level is insufficient, it is determined. If the previous display was the display 33b, the process proceeds to step 58 and the display 33b is displayed and held as in the previous display, and the yellow lamp 41 of the display unit is turned on and the warning lamp provided in the instrument panel 6 is also displayed. Operate. The buzzer is also activated during interrupt processing.

On the other hand, when the previous display is not the display 33b, in step 59, the temperature of the engine cooling water is detected by the cooling water temperature sensor 44, and the last time the engine is turned on by the timer built in the information display device 5. The elapsed time from the stop is measured. Then, in step 60, the cooling water temperature is equal to or lower than a predetermined temperature, which may be, for example, 50 ° C., and may be, for example, 20 minutes after the last engine stop.
Of the first state after a lapse of a predetermined time or more, and the cooling water temperature is equal to or higher than the predetermined temperature (50 ° C.) described above, and may be, for example, 5 minutes shorter than the second predetermined time after the engine is stopped. It is determined whether or not at least one of the second states after the lapse of the first predetermined time or more is satisfied. If either one of the first state and the second state is satisfied, the process proceeds to step 61 and the display 33b
Is performed and held, the yellow lamp 41 of the display unit is turned on, and a warning lamp disposed in the instrument panel 6 is operated. The buzzer is also activated during interrupt processing. Here, step 60 in FIG.
The graph shows the discrimination processing in. The vertical axis represents the elapsed time after the engine is stopped, and the horizontal axis represents the engine cooling water temperature. In the graph, the area A on the left side shows the first state described above, and the area B on the right side shows the second state described above. That is, in step 60, if the engine state is within the region represented by A + B, the process proceeds to step 61, and otherwise (region C), the process proceeds to step 62.

In step 60, the previous liquid level was not abnormal,
If none of the above conditions are satisfied, the process proceeds to step 62 and the display 33a is performed. Where steps 55, 58, 6
The indications 1 and 62 are continuously displayed until an ignition off signal is input from the ignition switch 42 in step 63.

Here, when the abnormal state display 33b is performed, even if it is clear that the normal state is achieved by replenishing the oil, if the above state is not satisfied in step 60, the normal state display 33 in FIG. May not be obtained at an early stage. However, according to the present embodiment, as shown in step 57, the memory built in the information display device 5 stores whether or not the previous liquid level was in the abnormal state, and this memory stores the previous liquid level in the abnormal state. Is stored, the liquid level can be displayed even if neither the first state nor the second state is satisfied. If the oil is not replenished, the abnormal state display 33b is displayed early and the oil is The engine oil level normal condition display 33 can be obtained early if replenished.

By the operation of steps 59 and 60, for example, when the engine is stopped for a very short time and then stopped, that is, when the engine is stopped before warming up, it takes a longer time than usual before the oil level can be displayed. In short, when the engine is stopped after operating for a relatively long time, that is, when the engine is stopped after warming up, the oil level can be displayed early.

During normal driving, the display 33a in FIG. 7 is displayed to indicate that the engine oil level is not displayed. This means that the oil level is not displayed unless the condition in step 60 in FIG. 10 is satisfied. This is to clarify, for example, to avoid a situation where an inconsistent display is held when the oil level is lowered due to oil leakage or abnormal wear during traveling.

12 to 14 show the coolant level display 34 showing the excess or deficiency of the engine cooling water. Since the coolant level cannot be accurately detected during the engine operation, it is not possible to operate it during normal engine operation. The display 34a shown in FIG. 13 indicates that the coolant level is not detected and displayed. The coolant level is detected when the ignition switch is turned on, and if the coolant level is appropriate, an indication to that effect is given as shown in Fig. 12, the green lamp 40 is lit, and the coolant level is insufficient. Display 34b as shown in Figure 14 if
Then, the yellow lamp 41 is turned on, and the warning lamp or the warning buzzer provided in the instrument panel 6 is operated in the same manner as described above.

The washer liquid level display 35 is for calling the driver's attention when the amount of the washer liquid is reduced, and a detailed description thereof will be omitted.

The oil level display 33 and the coolant level display 34 described above are performed only when the vehicle is started. When an abnormality in the oil level or the coolant level is detected when the vehicle is started, the display 33b (FIG. 8) is displayed by interrupt processing.
Alternatively, the display 34b (FIG. 14) is displayed, and this state is stored until oil or coolant is replenished. Therefore, if you press the system check push button 14,
Although other display items are displayed, when the oil level display 33 or the coolant level display 34 is performed, the abnormal display will be performed again.

The key 28 is used for setting the time or resetting the value of the odometer.

<Effects of the Invention> As described above, according to the present invention, when the viscosity of the engine oil or the like in the engine warm-up completion state is low, the first setting which may be relatively short as the elapsed time after the engine is stopped When the time has elapsed, the liquid level is detected after the ignition switch is turned on, and if the viscosity is high in the cold state, consider the time until the engine oil, etc. returns after the engine is stopped. If the liquid level is not detected until the set time of 2 has passed and the liquid level is detected after the liquid has sufficiently returned, if the previous liquid level is abnormal, the first predetermined time elapses. The liquid level can be detected before, and if it is abnormal this time as well, prompting the liquid replenishment will prompt the liquid level to prevent misunderstanding by the driver. Can be carried out with high reliability and high responsiveness, and rational maintenance and management of the vehicle becomes possible.

[Brief description of drawings]

FIG. 1 is a front view of a dashboard equipped with an information display device incorporating a liquid level display device according to the present invention. 2 and 3 are perspective views showing the information display device of FIG. 1 in detail. FIG. 4 is a conceptual diagram showing a selection procedure of display contents in the information display device shown in FIGS. FIGS. 5 to 8 and FIGS. 12 to 14 are front views showing the display contents of the information display device shown in FIGS. 1 to 3. FIG. 9 is a block diagram showing the structure of a liquid level display device according to the present invention. FIG. 10 is a flow chart showing the operation of the liquid level display device according to the present invention. FIG. 11 is a graph showing liquid level display conditions of the liquid level detecting device according to the present invention. 1 ... Dashboard, 2 ... Audio equipment 3 ... Air conditioner, 4 ... Air outlet 5 ... Information display device 6 ... Instrument panel 7 ... Steering wheel 8, 9 ... Projection part 10, 11 …… Elastic member 12 …… Display part, 13,14 …… Push button 15,16 …… Hinge, 17,18 …… Recessed part 19,20 …… Projection part, 21,22 …… Switch 23 ～ 29… … Switch key 30 to 35 …… Display, 40 …… Green lamp 41 …… Yellow lamp 42 …… Ignition switch 43 …… Oil level sensor 44 …… Cooling water temperature sensor 51 ～ 63 …… Step

Claims (1)

[Claims] 1. A device for detecting a liquid level as maintenance information in a vehicle engine, comprising: judging means for judging whether or not a temperature of cooling water of the engine has reached a predetermined temperature; and stopping the engine. Alternatively, the cooling water temperature has reached a predetermined temperature, having a time measuring means for measuring the elapsed time from the turning off of the ignition switch and a memory means for storing that when the liquid level is abnormal at the previous detection. When it is determined that the cooling level has not reached the predetermined temperature, the liquid level can be detected after the engine stops and the first predetermined time has elapsed. The liquid level cannot be detected until the second predetermined time, which is longer than the first predetermined time, is measured after the engine is stopped, and the liquid level abnormal state is stored in the memory means. In this case, the liquid level detecting device for a vehicle is capable of detecting the liquid level before the first predetermined time has elapsed.