JPH0518745B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an electronic control unit for a vehicle, and in particular, it controls a self-energizing means to turn on based on a key-on signal from a key switch to self-maintain energization when the key switch is turned off. The present invention relates to an electronic control unit for a vehicle that has the function of

[Description of Prior Art] One of the prior art related to the present invention is a power supply control device for an electronic control device described in Japanese Patent Application Laid-Open No. 122827/1982. In this system, the self-holding circuit is turned on when a key switch signal is applied when the key switch is closed, and the self-holding circuit is turned off when a predetermined condition is met. The self-holding circuit is configured to maintain power supply to the electronic control unit until a predetermined condition is met, so that necessary control can be performed even after the electronic control unit has been operated.

However, in such conventional technology, even if the key switch is closed, if the key-on signal is not given to the electronic control device for some reason, the self-holding circuit remains in the OFF state, and the self-holding circuit remains in the OFF state when the key switch is turned off. power supply is cut off,
There was a problem that necessary control was no longer performed.

[Object of the invention] The present invention has been made based on the above viewpoints, and
The object of the present invention is to provide an electronic control unit for a vehicle that is capable of self-maintaining power supply even when a key-on signal is not applied when a key switch is closed.

[Means for achieving the object] In the present invention, the self-energizing means is controlled to be turned on based on the key-on signal given when the key switch is in the on position and the starter position, and the energization is self-maintained when the key switch is off. In an electronic control unit for a vehicle equipped with a function, the key-on signal and a starter signal given while the key switch is in the starter position are input, and an abnormality of the key-on signal is detected based on a state in which only the starter signal is given. The above object is achieved by an electronic control unit for a vehicle, which has a means for detecting an abnormality in the key-on signal, and a means for recognizing that the key-on signal is given by detecting an abnormality in the key-on signal and controlling the self-energizing means to turn on. do.

That is, if only the starter signal is given but no key-on signal is given due to an abnormality in the key-on signal, it is recognized that the key-on signal is given and the self-energizing means is turned on. Therefore, the self-energizing means works and necessary control can be performed even after the key switch is turned off.

[Embodiment of the Invention] FIG. 1 is a configuration diagram showing an embodiment of the present invention.

In the figure, numeral 1 is a battery whose negative side is grounded, and an on-position switch 2 of a key switch KS, a power switch 3, a starter switch 4, and a self-energizing relay 5 are provided in parallel on the positive side of the battery 1. The on-position switch 2 is inserted between the battery 1 and the key-on signal input terminal a of the electronic control unit 6, and when it is closed, the electronic control unit 6
An H-level key-on signal is applied to the key-on signal input terminal a of the key-on signal input terminal a. The on position switch 2 is in the closed state when the key switch KS is operated to the on position and the starter position. The power switch 3 is inserted between the battery 1 and the power terminal b of the electronic control unit 6, and when it is closed, power is supplied to the electronic control unit 6. For power switch 3, key switch KS is in accessory position,
It is in the closed state when it is operated to the on position and the starter position. Starter switch 4 is
It is inserted between the battery 1 and the starter signal input terminal c of the electronic control unit 6, and when it is closed, a starter (not shown) is driven and an H level starter signal is sent to the starter signal input terminal c of the electronic control unit 6. It is beginning to give. Starter switch 4 is a key switch
When KS is operated to the starter position, it is in the closed state. The self-energizing relay 5 has its excitation coil 5a inserted between the battery 1 and the self-energizing control terminal d of the electronic control unit 6, and its normally open contact 5b bypassing the power switch 3 to connect the battery 1 and the electronic control. It is inserted between the unit 6 and the power supply terminal b.

In the electronic control unit 6, 7 is
In the AND circuit, one input terminal is connected to the key-on signal input terminal a via the inverter 8, the other input terminal is connected to the starter signal input terminal c, and its output is connected to the first switching circuit 9 and the counter 10. is given to. The first switching circuit 9 is
Using the output of AND street 7 as a switching control signal, AND
A clock is applied to the counter 10 while the output of the circuit 7 is at H level. The counter 10 is reset by the L level output of the AND circuit 7, and
When the output of the circuit 7 becomes H level, the reset state is released, the clock applied via the first switching circuit 9 is counted, and the count value is applied to the failure detection circuit 11. The failure detection circuit 11 provides an H level output to the second switching circuit 12 when the count value of the counter 10 reaches a predetermined value, and provides an L level output when the count value does not reach the predetermined value. The second switching circuit 12 has one selection contact 1
2a is connected to the key-on signal input terminal a, and the other selection contact 12b is held at the H level regardless of the on-position switch 2. The second switching circuit 12 uses the output of the failure detection circuit 11 as a switching control signal, selects one of the selection contacts 12a with the L level output of the failure detection circuit 11, and gives a key-on signal to the relay control circuit 13. 11 selects the other selection contact 12b and provides an H level signal to the relay control circuit 13. The relay control circuit 13 receives the signal selected by the second switching circuit 12 as well as the output of the NAND circuit 14 and the clock. The NAND circuit 14 outputs the output of the rotation speed zero detection circuit 15 and the vehicle speed zero detection circuit 1.
6, the output of the clutch-on detection circuit 17, and the transmission control display signal of the transmission drive unit 18,
a clutch control display signal of the clutch drive unit 19;
A starter signal via the inverter 20 is input. The zero rotational speed detection circuit 15 inputs an engine rotational speed signal from a rotational speed sensor 21 that detects the engine rotational speed, and when the engine rotational speed is zero, H
A level rotational speed zero signal is given, and when the engine rotational speed is not zero, an L level output is given. The zero vehicle speed detection circuit 16 inputs a vehicle speed signal from a vehicle speed sensor 22 that detects the speed of the vehicle, and provides an H level vehicle speed zero signal when the vehicle speed is zero, and provides an L level output when the vehicle speed is not zero. . The clutch on detection circuit 17 inputs a clutch position signal from a clutch sensor 23 that detects the position of a friction clutch 27, which will be described later, and gives an H level clutch on signal when the friction clutch 27 is completely connected. When not connected, it gives an L level output. The transmission drive section 18 operates the gear transmission 25 by driving the transmission actuator 24 in accordance with a transmission control signal, and when the transmission actuator 24 is not being driven, that is, the transmission actuator 24 receives a drive signal. If the transmission control display signal is not output, a transmission control display signal of H level is given.
If the vehicle is being driven, an L level transmission control display signal is given. The clutch drive unit 19 operates the friction clutch 27 by driving the clutch actuator 26 in response to a clutch control signal, and when the clutch actuator 26 is not being driven, that is, the clutch actuator 26 receives a drive signal. When the clutch is not being outputted, an H level clutch control display signal is given, and when the clutch is being driven, an L level clutch control display signal is given. The NAND circuit 14 determines that the engine speed is zero, the vehicle speed is zero, the friction clutch 27 is fully engaged, the gear transmission 25 and the friction clutch 27 are not in operation, and the starter signal is not present. When the self-energization termination condition that satisfies all the conditions not given is satisfied, an L level output is given, and otherwise an H level output is given. NAND circuit 14 is low
In the state where the level output is provided, the electronic control unit 6 is in an idling state in which it does not provide any control output to external devices such as the transmission actuator 24 and the clutch actuator 26, and the vehicle and engine are stopped. The relay control circuit 13 sets the self-energization control terminal d to the ground level by receiving the H level signal from the second switching circuit 12, and the output of the NAND circuit 14 becomes H level.
It has a function of setting the self-energization control terminal d to a high impedance state when the L level output state of the NAND circuit 14 continues for a predetermined period of time after being inverted from the level to the L level.

In the above configuration, assuming that the key-on signal given from the key switch KS is normal, when the on-position switch 2 is closed, the power switch 3 linked to this is also closed, and the electronic control unit 6 is When power is applied, H
A level key-on signal is given to the electronic control unit 6, and in this state, the starter switch 4
By closing, an H level starter signal is given to the electronic control unit 6.
Therefore, the output of AND circuit 7 is constant at L level,
The first switching circuit 9 and the counter 10 do not operate,
Therefore, the failure detection circuit 11 provides an L level output to the second switching circuit 12. The second switching circuit 12 selects one selection contact 12a, a key-on signal is given to the relay control circuit 13, and the self-energizing relay 5 is energized. As a result, the normally open contact 5b closes, and the energizing circuit passing through the power switch 3 and the normally open contact 5b close.
An energizing circuit passing through b is formed. The NAND circuit 14 provides an H level output to the relay control circuit 13 in order to turn off the friction clutch 27 etc. by applying power, and when the starter switch 4 is closed, a starter signal is provided and the engine starts rotating. Since the vehicle enters the operating state, the H level output is maintained. When the key switch 2 is opened to turn off the engine while the vehicle is stopped, the power switch 3 is simultaneously opened and no key-on signal is given to the electronic control unit 6. Power is supplied to the electronic control unit 6 via a normally open contact 5b.
The engine speed is zero, the vehicle speed is zero, the friction clutch 27 is fully engaged, the gear transmission 25 and the friction clutch 27 are not in operation, and the starter signal is not applied. When the self-energization termination condition that satisfies all of the above conditions is met, the output of the NAND circuit 14 becomes L level. The relay control circuit 13 puts the self-energization control terminal d into a high impedance state when the L level output state of the NAND circuit 14 continues for a predetermined period of time. As a result, the self-energizing relay 5 is deenergized, the normally open contact 5b is opened, and the power supply to the electronic control unit 6 is cut off.

On the other hand, if an abnormality occurs in the key-on signal given from the key switch KS due to a disconnection, etc., and the key-on signal is not given to the electronic control unit 6 even if the on-position switch 2 is closed,
Under this condition, a starter signal is applied to the electronic control unit 6 by closing the starter switch 4. Therefore, the output of the AND circuit 7 becomes H level, and at the same time the first switching circuit 9 is closed, the reset state of the counter 10 is canceled and the count value is given to the failure detection circuit 11. When the count value of the counter 10 reaches a predetermined value, the failure detection circuit 11 outputs an H signal to the second switching circuit 12.
Gives level output. As a result, the second switching circuit 12 selects the other selection contact 12b, and an H level signal is given to the relay control circuit 13. Other operations are as described above.

FIG. 2 is a configuration diagram showing another embodiment of the present invention, and FIGS. 3A and 3B are control flowcharts for the configuration shown in FIG. This figure shows the case where the self-energizing relay 5 is controlled by using the same reference numeral as in FIG. 1, and the same reference numerals as in FIG. Note that terminals w, x, y, and z of No. 3A are connected to terminals with the same symbols in FIG. 3B. Hereinafter, the operation of the configuration shown in FIG. 2 will be explained using FIGS. 3A and 3B together.

Assuming that the key-on signal given from the key switch KS is normal, power is applied to the electronic control unit 30 when the power switch 3 is closed, and after initialization it enters step 40 to determine whether or not there is a key-on signal. Go to step 41 via w. Steps 41, 42, 43, 44, 45, 46
So, is the number of engine circuits zero, the vehicle speed is zero, or is the friction clutch 27 in the connected state, that is, the clutch is on?
It is determined whether the gear transmission 25 is being controlled, the friction clutch 27 is being controlled, and the presence or absence of the starter signal. The determination of whether the engine rotational speed is zero, the vehicle speed is zero, and the clutch is on are performed based on the engine rotational speed signal from the rotational speed sensor 21, the vehicle speed signal from the vehicle speed sensor 22, and the clutch position signal from the clutch sensor 23, respectively. Therefore, the judgment as to whether or not the gear transmission 25 and the friction clutch 27 are being controlled is as follows.
This is done based on whether or not a drive signal is being output to the transmission actuator 24 and clutch actuator 26, respectively. When the engine speed and vehicle speed are zero, the friction clutch 27 is fully connected, and the gear transmission 25 and the friction clutch 2
If the self-energization end condition, which is a state in which 7 is not controlled and no starter signal is given, is satisfied, steps 41 to 46 are passed and step 47 is reached.
will enter. However, when power is applied, the friction clutch 27 is turned off, etc.
Also, when the starter switch 4 is closed, a starter signal is given and the engine rotates, so steps 41 to 46 can be started.
48, the internal timer is reset at step 48, and the flag _F2 is set to "0" at the next step 49. Then terminal y
After that, the process enters step 50 and sets the self-energizing control terminal d to the ground level. As a result, the self-energizing relay 5 is energized, and an energizing circuit passing through the normally open contacts 5b is formed. Step 51 after step 50
If there is a key-on signal, the process returns to step 40 via normal control at step 52. As long as the key-on signal is normal and the key-on signal is provided by closing the on-position switch 2, the above-described operation is repeated. When key switch 2 is opened to turn off the engine while the vehicle is stopped, power switch 3 is simultaneously opened.
is opened and the electronic control unit 30
key-on signal is no longer given to the Power is supplied to the electronic control unit 30 via the normally open contact 5b. When the key-on signal is no longer given, the failure flag F _F is set in steps 40 to 53.
enter into the judgment. Since the failure flag F _F is set to "0" at the time of initialization, steps 53 and 54 are performed to determine whether or not there is a starter signal. Since the starter signal is not given while the key switch 2 is open, the internal timer is reset in steps 54 and 55, and the flag _F1 is set to "0" in the next step 56, and then the process returns to step 51.
to go into. Since key switch 2 is open, the process proceeds from step 51 to step 57 to determine flag _F1 .
Next, the process enters step 58 to determine whether the control ends when the key is turned off. In step 58, when the control is terminated when the key is turned off, the predetermined control when the key is turned off, such as the off control of the friction clutch 27 and the neutral control of the gear transmission 25, is completed after the key switch 2 is opened and no key-on signal is given. If the process has not been completed, the process returns to step 40 via step 52, and if it has been completed, the process returns to step 59 via terminal z. When the predetermined control at the time of key-off is completed and step 59 is entered, the self-energization control terminal d is brought into a high impedance state. As a result, the self-energizing relay 5 is deenergized, the normally open contact 5b is opened, and the power supply to the electronic control unit 30 is cut off.

On the other hand, if an abnormality occurs in the key-on signal due to a disconnection or the like, and an H-level key-on signal is not given to the electronic control unit 30 even if the on-position switch 2 is closed, the process starts from step 40 after initialization. 53 and enter step 54.
If no starter signal is given, the step
From step 54, the process goes through step 55, step 56, step 51, step 57, step 58, step 52, and returns to step 40. By giving a starter signal,
Step 60 is entered from step 54, and flag _F1 is determined. Flag F ₁ is set to "0" during initialization
Since the flag F1 is set to ``1'' at step 60, step 61 is entered to start the internal timer, and at the next step 62, the flag <sub>F1</sub> is set to ``1''.
Enter step 63, time-up judgment. step
If the predetermined time _t1 has not elapsed since the start of the internal timer 61, the process returns from step 63 to step 40 via step 51→step 57→step 52. When the predetermined time _t1 has elapsed, the process goes from step 63 to step 64, where the failure flag _FF is set to "1", and then step 50 is started, where the self-energization control terminal d is set to the ground level. As a result, a current-carrying circuit passing through the normally open contact 5b is formed as described above. After step 50, step 51 → step 57
→ Return to step 40 via step 52, and then
53 failure flag F _F is determined. Since the flag F _F has been set to "1" in step 64, the program enters step 41 via terminal w from step 53, and performs the engine speed and vehicle speed zero determination, clutch on determination, and gear transmission determination in steps 41 to 46. 25 and friction clutch 27 are being controlled, and the presence or absence of a starter signal is determined. When the engine speed and vehicle speed are zero, the friction clutch 27
If the self-energization termination conditions are not met, which are fully connected, gear transmission 25 and friction clutch 27 are not controlled, and no starter signal is provided, steps 41-46 From there, the process enters step 48, and after processing steps 48 and 49, returns to step 50 via terminal y. The above-described operation is repeated until the self-energization end condition is not satisfied. When the ON position stitch 2 is opened to turn off the engine when the vehicle is stopped and the self-energization termination condition is satisfied, steps 41 to 46 are executed.
Through this step, the judgment of flag _F2 in step 47 is entered.
In this case, the flag _F2 is "0" and step 47 is executed.
Then, from step 47 to step 65, the internal timer is started, and the next step 66 is started.
After the flag _F2 is set to "1" in step 67, the timer up determination is made. If the predetermined time _t2 has not elapsed since the start of the internal timer in step 65, the process is transferred from step 67 to step 51 via terminal x.
Return to Step 67 occurs when the predetermined time _t2 has elapsed.
Then, the program enters step 59 and puts the self-energization control terminal d into a high impedance state. As a result, the power supply to the electronic control unit 30 is cut off.

[Effects of the Invention] As explained above, according to the present invention, when only the starter signal is given but no key-on signal is given due to an abnormality in the key-on signal, the self-energization is performed by recognizing that the key-on signal is given. Since the means is configured to be turned on, the self-energizing means works even when a key-on signal is not given when the key switch is turned on, and the necessary control can be performed after the key switch is turned off.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing one embodiment of the present invention, and FIG.
The figure is a configuration diagram showing another embodiment of the present invention, FIG. 3A
3B is a control flowchart of the configuration shown in FIG. 2. KS...Key switch, 2...On position switch, 4...Starter switch, 5...Self-energizing relay, 6...Electronic control unit, 7...
AND circuit, 8, 20...Inverter, 9, 12
...Switching circuit, 10...Counter, 11...Failure detection circuit, 13...Relay control circuit.

Claims (1)

[Claims] 1. A vehicle electronic control unit having a function of controlling a self-energizing means to turn on based on a key-on signal given when the key switch is in the on position and the starter position, and self-maintaining the energization when the key switch is off. means for inputting a starter signal applied while the key-on signal is in the starter position and the key-on signal, and detecting an abnormality in the key-on signal based on a state in which only the starter signal is applied; An electronic control unit for a vehicle, comprising means for recognizing that a key-on signal is given and controlling the self-energizing means to turn on.