JPH0224949Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for displaying the preheating state of an air heater used at the time of starting an automobile, and more particularly to a starting preheating display device for an automobile that uses an indicator light to indicate the preheating state.

2. Description of the Related Art A starting preheating device is known that operates an air heater attached to an intake manifold of an engine when starting an automobile, thereby heating intake air, helping vaporize fuel, and improving ignitability. When this starting preheating device completes intake air heating, it normally lights up an indicator light to notify the driver. Moreover, in order to notify the driver when the air heater is in the starting preheating operation, another indicator light is provided and is turned on.
By checking the lighting state of such an indicator light, the driver makes a decision to drive the starter or to refrain from driving the starter for a while.

By the way, conventional starting preheating devices detect the water temperature, etc., and when the water temperature is lower than the set temperature (for example, about 0 to -5 degrees Celsius), the air heater is started and preheated, and at the same time, the starting preheating indicator light is turned on, and the preheating is started according to the set temperature. When preheating is completed after a certain period of time, or when the water temperature is higher than the set temperature, another start-ready indicator light is turned on to indicate that starting is permitted. The use of two indicator lights to indicate starting preheating in this way increases costs and also tends to cause problems in securing space on the instrument panel.

An object of the present invention is to provide a starting preheating display device for an automobile that can display starting preheating using a single indicator light.

In order to achieve the above object, the present invention is connected to a starting preheating control means for preheating intake air prior to cranking of the engine using an air heater, and displays the starting preheating state of the air heater using an indicator light. An indicator light control means is connected to the light, and the indicator light control means timely sends an output current to the one indicator light installed, and the continuous lighting and lighting of the indicator light determines when the air heater needs to be preheated and when it is not needed. It is characterized by a separate display of when it is needed and when it is needed.

Such a starting preheating display device for an automobile can distinguish whether starting preheating is necessary or not by continuously lighting and blinking one indicator light.

FIG. 1 shows a starting preheating display device for an automobile as an embodiment of the present invention. This display device is an indicator light 1 installed on the instrument panel of a car (not shown).
and a microcomputer (hereinafter simply referred to as CPU) 2 as an indicator light control means for controlling this indicator light (green lamp here). The above-mentioned indicator light control means is connected to start preheating control means also built into the CPU 2 (see FIG. 2).
The starting preheating control means controls the air heater 3 for heating the intake air of the automobile.
A signal current for opening/closing is output to the heater relay 5 installed between the This heater relay includes a fuse 6 for overcurrent prevention. An engine key switch (hereinafter simply referred to as a key switch) 7 and a heat/cold start switch (hereinafter simply referred to as a cold start switch) 8 are installed in the driver's seat of an automobile (not shown).

As shown in Figure 1, the key switch 7 has three positions: a lock position, an accessory position where the B and ACC terminals are connected, an on position where the B, ACC and M terminals are connected, and a B, ACC and M terminal. In addition to connecting the H and F terminals, the H
and the starter position where each terminal of F is connected.

This heat position heats and operates a glow plug for starting the engine (not shown), and is always biased toward the on position by a return spring. The key switch 7 has a B terminal connected to the power supply 4 and other terminals connected to each terminal in the CPU 2. The cold start switch 8 connects both terminals B and L when turned on, disconnects both terminals B and L when turned off, and simultaneously connects a water temperature sensor 9 (not shown) for detecting the water temperature of the engine to the CPU 2 side. heat switch 8
The L terminal of the key switch 7 and the H terminal of the key switch 7 are connected through a diode 10. Note that this L terminal may be connected to an exhaust brake circuit (not shown), and the exhaust brake may be operated in conjunction with turning on the cold start switch 8 to promote warm-up. The alternator 11 and the a terminal between the air heater 3 and the relay 5 are connected to the CPU 2, and a signal for detecting the presence or absence of voltage as an on/off signal is inputted from these.

In the memory of such CPU 2, the set water temperature value corresponding to outputting the signal current to heater relay 3 is stored.
ta is amnesticized. Furthermore, a control program as shown in the flowchart of FIG. 7 is stored in the memory. In addition, S in Figures 7 and 8
1 to S22 indicate each step of the flowchart.

The operation of such a starting preheating display device for an automobile will be explained with reference to the operation timing diagrams of FIGS. 3 to 6 and the flowchart of FIG. 7.

First, as shown in FIG. 3, the case where the engine water temperature t is higher than the set water temperature value ta will be described below.

When the CPU 2 starts the program, it reads the output of the alternator 11, confirms that there is no output, confirms that the air heater 3 is inactive, that is, there is no output from the a terminal, and performs initial settings accordingly. (Step 1). In step 2, determine whether key switch 7 is on or above (on, heat, and starter positions), and select YES to proceed to step 3.
If NO, proceed to step 4. In step 3, if the cold start switch 8 is off, the process goes to step 5, and if it is on, the process goes to step 6. In step 5, read the water temperature t. In step 7, it is determined whether the current water temperature t is lower than the set water temperature ta, and if YES, the process goes to step 8 and NO.
Proceed to step 9. At step 9, green lamp 1
It lights continuously for the set continuous lighting time tb, and then turns off.
At this point, the starter is turned (ST) and it is determined whether or not the alternator output is on (STEP).
10) If YES, return to the end (step 4); if NO, return to step 2; if the key switch is off, return to the end (S4); if it is on, repeat steps 3 and onward.

Next, the case where the engine water temperature t is lower than the set water temperature value ta and the engine is restarted after stalling (see Fig. 4) will be described below.

The CPU 2 passes through steps 1, 2, 3, 5, and 7 and enters control in step 8. In step 8, it is determined whether the set reheating unnecessary time ti has elapsed, and if YES, the process proceeds to step 11; if NO, the process proceeds to step 12. step
At step 11, a signal current is applied to the heater relay 5 so that the air heater 3 is heated for the preheating time th. In addition, the air heater and green lamp blink approximately.
This is done after a heat delay time ts of about 0.2 seconds.
Next, in step 13, set the flashing time for green lamp 1.
Give a flashing current during tp, then continue to set continuous lighting time to
A continuous current is applied during the period. If there is an output from the alternator during this period, the process goes to step 15; if NO, the process goes to step 2.
Return to (step 14). When the starter is turned on and the process advances to step 15, instead of outputting preheating output to the air heater, a heating operation is started for the set afterheat time tf to the air heater. At step 16, if there is an output from the alternator, the process ends (step 4).
If there is no one, the process returns to step 2 via step 18. Here, step 18 is reached, the afterheat is cut off, and the process returns to step 2.

In other words, it is assumed that an engine stall occurs in which the output of the alternator is off. After this, the process goes through steps 2, 3, 5, and 7 again to reach step 8. Here, it is determined whether the set reheating unnecessary time ti has already elapsed before the current time, and the step
Proceed to step 12 and turn on green lamp 1 for the set lighting time to. Next, in step 21, it is determined whether the starter is on or not, and if NO, the process goes to step 14, and if YES, the process goes to step 22. At this point, the air heater 3 is turned on. Then, the process returns to step 14, and then proceeds to step 15, where the heating operation of the air heater begins during the set afterheat time tf. After this, proceed to step 16.

Next, the case where the engine water temperature t is lower than the set water temperature value ta and the engine operates normally (see Fig. 5) will be described below.

CPU2 is 2, 3, 5, 7, 8 from step 1.
Control is performed to reach the end via steps 11, 13, 14, 15, and 16. This causes the alternator output to remain on. In this case as well, the green lamp 1 blinks for the set blinking time tp, and then lights continuously for the set continuous lighting time to.

Next, the case where the engine water temperature t is lower than the set water temperature value ta and the engine does not start (see Fig. 6) will be described below.

CPU2 starts from step 1, 2, 3, 5, 7,
Control is performed to reach step 14 through steps 8, 11, and 13. Since the starter does not turn on, there is no output from the alternator, and the process returns to step 2.
Repeat the control until the key switch turns off (proceed to end).

In the above control, when the cold start switch 8 is turned on in step 3, the process proceeds to step 6. Here, based on the maximum resistance of the water temperature sensor 9, it is determined that t<ta, and the air rotor 3 continuously enters the heating operation. After this, if it is determined in step 17 that there is an output from the alternator, the process goes to end (step 4), and returns to step 2 with NO.

In the above, following steps 6, 11, 15, and 22, as shown in FIG. 8, the process proceeds to step 19, where it is read whether the output of the a terminal is on or not. , 13, 16, and 14, the configuration may be configured such that if it is off, the process proceeds to step 2 from step 20 on the NO side.

In this case, even though the air heater is on, the ON signal is not detected when the fuse 6 is blown.
times/second), that is, the time width is narrower (approximately 4 times per second).
times/sec) outputs a blinking signal to indicate an abnormality and returns to step 2. In this way, one green lamp 1 can be used as an abnormality indicator light, which has the effect of reducing costs.

As described above, in the vehicle starting preheating display device according to the present invention, one indicator light (green lamp) 1 is operated by the indicator light control means in at least two display modes: flashing and continuous lighting. Therefore, with one indicator light, it is possible to distinguish between when starting preheating is required and when heating is not required, which is effective in reducing costs and making it easier to secure a space for installing the indicator light on the instrument panel.

[Brief explanation of the drawing]

Fig. 1 is a schematic configuration diagram of a display device for starting preheating for an automobile as an embodiment of the present invention, Fig. 2 is a block diagram of the components of the present invention, and Figs. FIG. 7 is a flowchart of the program for the display device, and FIG. 8 is a diagram for explaining the lighting state of the indicator light and the operation timing of the related alternator. FIG. 8 is a flow chart of the program for the display device as another embodiment of the present invention Flowcharts of the main parts are shown. 1... Indicator light, 2... CPU, 3... Air heater, 7... Key switch, 8... Cold start switch, 9... Water temperature sensor, 11... Alternator.

Claims (1)

[Scope of utility model registration request] In a starting preheating display device for an automobile, which is connected to a starting preheating control means for preheating intake air by an air heater prior to engine cranking, and displays the starting preheating state of the air heater using an indicator light, the indicator light control means is attached to the indicator light. The indicator light control means timely sends an output current to the indicator light that is connected and installed, and the continuous lighting and blinking of the indicator light distinguishes when starting and preheating of the air heater is necessary and when it is not necessary. An automobile starting preheating display device characterized by the following.