JPS60162023A - Control device for automatic stop/restart of engine - Google Patents

Abstract

PURPOSE:To obtain a highly reliable device for automatic stoppage and restarting of an engine by utilizing a sensor detecting operational conditions of already equipped clutch and mission and confirming running of a vehicle and further deciding troubles of an engine rotation sensor and a car speed sensor. CONSTITUTION:After detecting operational conditions of a clutch and a mission and subsequently confirming traveling of a vehicle, a trouble of an engine rotation sensor is discriminated from that of a car speed sensor, and an alarm is given in case abnormality of the sensor is generated. Since automatic engine stoppage and restarting control are performed in case both engine speed and car speed are detected, there is not mistaking of surge pulse detection due to a noise for a car speed pulse regardless of a vehicle being in a state of stoppage. Further, since an alarm is generated when either the engine rotation sensor or the car speed sensor is in trouble, the sensor in trouble can be clarified to urge an operator to take some measure promptly. Furthermore, since automatic engine stoppage and restarting control is not performed in this case, safety is raised.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an engine automatic stop restart control device for automatically stopping or restarting an engine.

(Prior art) In general, on route passes that are frequently driven in urban areas, the time spent idling and stopped due to waiting at traffic lights, stopping in traffic jams, stopping at pass stops, etc. accounts for more than 40% of the total running time. Sometimes. During the stop period during idling, fuel is wasted, the air is polluted, and passengers always feel uncomfortable due to the vibrations and noise during idling, which are unique to the path.

Therefore, when driving in a city, when a car stops at an intersection or other place, the engine automatic stop/restart system automatically stops the engine under predetermined conditions and automatically starts the engine using the normal starting operation. is being developed.

FIG. 1 is a schematic block diagram of a conventional engine automatic stop/restart device. For example, JP-A-58-15729
The publication states that the control circuit B is operated by the output signals of various sump A such as the vehicle speed sensor, clutch switch, headlight switch, air conditioner switch, etc. to stop the engine.
When driving the starter C, whether or not the engine stop condition and start condition are met is determined by the logical product of the engine rotational speed signal, the signal indicating the alternator's power generation state, and the signal indicating the vehicle starting operation state. A method is disclosed in which the determination is made based on the following.

Further, Japanese Patent Application Laid-open No. 58-5444 discloses an engine equipped with a display device that displays the amount of fuel consumption saved by performing such automatic engine stop/restart control.

Furthermore, in order to improve the stability of automatic engine stop control, engine stop control is not performed when a failure of the vehicle speed sensor is determined (Japanese Patent Laid-Open No. 58-15732).
(Japanese Unexamined Patent Publication No. 58-23251), when a change in vehicle speed that cannot actually occur is detected, it is assumed that some abnormality has occurred and automatic engine stop control is not performed. Proposed.

(Problems with the Prior Art) As described in Japanese Unexamined Patent Publication No. 58-15729, in order to detect the engine operating state, the output voltage of the alternator and the oil pressure are detected in addition to the engine rotation sensor. If the conditions for automatic engine stop/restart are determined by the logical product of two or more of these items, the amount of signal processing in the input circuit increases, and the cost also increases due to the increase in the number of parts. Furthermore, as described in Japanese Patent Application Laid-open No. 58-15732 and Japanese Patent Application Laid-open No. 58-23251, when detecting an abnormality in a vehicle speed sensor, it is not possible to simply detect the presence or absence of a pulse from the sensor. There was a risk that surge pulses from various relays and switches could be mistaken for vehicle speed pulses even though they had stopped.

(Object of the Invention) The object of the present invention is to confirm that the vehicle is running by using sensors that detect the operation status of the clutch and the engine, which are already equipped for other purposes, and to use the engine rotation sensor. To obtain a highly reliable engine automatic stop/restart device by performing automatic engine stop/start control after determining a failure of a vehicle speed sensor.

In addition, when performing automatic engine stop/restart control,
If the set conditions are not met, a warning is issued to identify the faulty sensor and allow the driver to take appropriate measures.

(Summary of the Invention) The automatic engine stop/restart control device of the present invention automatically stops/restarts the engine when signals from sensors that detect the operating states of various parts of a vehicle and engine operating states meet predetermined conditions. For those that perform start control, the operation status of the clutch and transmission is detected to confirm that the vehicle is running, and then the engine rotation sensor and vehicle speed sensor are determined to be malfunctioning, and both sensors are operated normally. When both engine rotation and vehicle speed are detected, the engine automatically stops.
When restart control is started and either engine rotation or vehicle speed is not detected, an abnormality warning is issued.

(Example) Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

FIG. 2 is a schematic block diagram of the automatic engine stop/restart device of the present invention. In the figure, ■ is an electronic control unit consisting of a computer, etc., and inside it is a CPU, R
It has OM, RAM, timer, human output port, relay drive circuit, etc. 2 is a power switch, 3 is a vehicle speed sensor that detects the running state of the vehicle, 4 is an engine rotation sensor that detects the engine rotation state, 5 is a neutral switch that is turned on when the transmission is set to neutral, and 6 is a clutch pedal that is fully depressed. This is a crunch switch that is turned on when the driver's foot is released from the driver's foot.

Reference numeral 7 denotes a pneumatic pressure switch installed in an air tank filled with air, which is used to connect and disconnect the brake and flanch, and is turned on when the pressure drops below a predetermined value. 8 is a room lamp switch, 9 is a room lamp switch, 10 is a fog lamp switch, 11 is an air conditioner main switch, 12 is a heat switch, and 13 is a key switch for driving the starter. 14 is a starter engager for energizing the starter engager Q coil.
This is a coil terminal, and the voltage generated at the terminal 14 is input to the electronic control device 1 and used to count the number of times the starter is used. 15 is a self-diagnosis switch for operating the electronic control unit 1 in a self-diagnosis mode, and 16 is a self-diagnosis switch for operating the electronic control unit 1 in a self-diagnosis mode; This is a switch for erasing the section. 17 is an engine stopper for stopping the engine, and a motor or an air cylinder or the like is used. At the tip of the engine stopper 17,
It is connected to an intake cut valve or fuel cant lever necessary to stop the diesel engine. 1
8 is a starter, 19 is an air conditioner fan that sends out cold air in the air conditioner, and 20 is a heater fan that sends warm air to the feet of the passenger deer in the heater device. 21
22 is a warning device consisting of a lamp that displays the operating status of the engine automatic stop/restart control device, a lamp that flashes in synchronization with the on/off of various switches in the self-diagnosis mode, and a buzzer that issues an alarm; is total driving time, automatic engine stop time, fuel saving effect, number of engine stops,
This is a 7-segment digital display device that numerically displays various display items such as the number of times the starter has been used, and each display item can be changed with a switch.

Here, the warning device 21 and the display device 22 are an electronic control device l.
It may be installed separately from the electronic control device 1 or built into the electronic control device 1.

FIGS. 3 to 6 are explanatory diagrams and flowcharts for determining the engine automatic stop/restart control start conditions according to the present invention. FIG. 3 is an explanatory diagram of the correlation between the operating states of the clutch and the engine and the sensor signals of the engine rotation sensor and vehicle speed sensor. When the clutch is depressed, the clutch switch signal is turned off, and when the foot is released, the Claraci switch signal is turned on. The neutral switch is turned on when the engine is in neutral N, and the neutral switch is turned off in any position other than neutral N. In row A in Figure 3 (a), when the clutch switch is on and the neutral switch is off, the engine and drive system are directly connected, so if the engine does not rotate, Even if the vehicle is coasting, the vehicle is always stopped and the vehicle speed is not detected. Conversely, if the engine is rotating, the vehicle is always running and the vehicle speed is detected. However, the mouth
C. In the second column, the correspondence between the presence or absence of engine rotation and the presence or absence of vehicle speed is not determined due to differences in conditions such as flat road, downhill, or coasting.

From this, in the state of column A, that is, when the Clarity switch is on and the neutral switch is off, the presence or absence of engine rotation and the presence or absence of vehicle speed correspond to 1:1, so Figure 3 (b) The failure part can be clearly determined by a combination like this. However, it is not possible to clearly determine a failure in the columns ``Open'', ``C'', and ``2'', so combinations such as (b) cannot be applied.

Based on the above, the present invention applies the conditions in column A of FIG. 3(a) to make it possible to clearly determine the failure location.

FIG. 4 is an explanatory diagram of the operating states of the neutral switch and clutch switch when shifting the transmission. To explain the shift operation from 1st gear in Figure 4(a) to 2nd gear in Figure 4(C) as an example, in Figure 4(a) the neutral switch is off and the clutch is released. The clutch switch is on. Figure 4(b)
Now, the transmission will be put into neutral at least once for the shift operation, so the neutral switch should be on.
Also, since the clutch is depressed at least once, the clutch switch is off. Next, in the 2nd speed state shown in FIG. 4(C), the neutral switch is off, and since you take your foot off the clutch and the clutch, the clutch switch is on. Therefore, before determining whether the engine rotation sensor is abnormal, the operation of the neutral switch and the clarification switch is detected at least -. times as shown in FIG. 5 (part 1). Note that although this flowchart also serves as abnormality detection for the clutch switch, abnormality detection for the neutral switch is performed in self-diagnosis mode.

Areas a, b, and c in Figure 5 (Part 1) are shown in Figure 4 (a).
), (b), and (c).

(1) In step P, the clutch operation flag is cleared. This flag becomes 1 when the clutch is depressed, and becomes 0 when the clutch is not depressed. In step P2, it is checked whether the clutch switch is on, and in step P3, it is checked whether the neutral switch is off. Step P.

~P3 is the processing procedure corresponding to FIG. 4(a).

(2) Next, the state shifts to the state shown in Figure 4 (b), so in step P4 confirm that the neutral switch is on, and in step 2, the flag is 1, that is, the clutch is depressed and the clutch switch is turned off. Check that it is.

If it is determined in step P4 that the neutral switch remains off, the flag is checked in step P5, and when the flag is 1, that is, the clutch is depressed, the process returns to step P4 again to check the state of the neutral switch. . When the flag is 0, the state of the clutch switch is determined in step P6, and if the clutch switch is on, the process returns to step P4 and the state of the neutral switch is determined. If the clutch switch is off, the flag is set to 1 in step P7 and the process returns to step P4. Pi, P5, P, . . . P7 are loops that detect whether or not the clutch is depressed until the transmission is put into neutral.

On the second day of operation, if the flag force is O1 (that is, the clutch is not depressed), proceed to step P9 and check the state of the neutral switch.

If the neutral switch is on, then step P
At LO, it is determined whether the clutch switch is on or off. If it is on, the process returns to step 2, and if it is off, the process proceeds to the first step shown in FIG. 4(C).

At step P9, the neutral switch is off. In other words, if it is determined that the transmission has been shifted without ever operating the clutch, it is determined that the clutch switch is abnormal, and alarm mode 1 is executed (step P11.P
12). In other words, on P day, P day, P, o, if the transmission is set to neutral without the clutch being depressed even once, at least once before shifting the transmission next time,
This is a loop that detects whether or not the clutch is depressed. If no debris is detected on the clutch, it is considered abnormal.P
Proceed to the processing of i I and PI 2. .

(3) In the state of i4 diagram (c), check whether the neutral switch is off and the clutch switch is on at step P.
Check with 1iS and PI4.

Following the clutch switch abnormality determination, the engine rotation sensor abnormality and vehicle speed sensor abnormality are determined in accordance with the procedure shown in the flowchart of FIG. 5 (part 2). As explained in the flowchart of Fig. 5 (Part 1), the detection of an abnormality in the engine rotation sensor and the abnormality in the vehicle speed sensor involves detecting at least one activation of the clutch switch and neutral switch in the previous step. It is a premise.

The flowchart in FIG. 5 (Part 2) will be explained below.

(1) The engine rotation speed is the first set rotation speed R1rp+n
(for example, 50 rpm) or more, that is, whether or not the engine is started (step P15). If it is determined that the engine is stopped, the process proceeds to step PI7, where it is determined whether the vehicle speed is equal to or higher than the first set value S t K m/h (for example, 5 Km/h), that is, whether or not there is a vehicle speed. Ru. When the vehicle speed is detected, it is determined that the engine rotation sensor is abnormal, and step PIF is executed to generate an abnormality alarm (
Step P19) (2) In step P15, the engine rotation speed is set to R1r.
If it is determined that the engine is rotating at pm or higher, step P
16, it is checked whether the engine speed has risen to a second set value R2rpm (for example, 1500rpm) or higher, and if this condition is satisfied, it is determined that the vehicle is running,
When the vehicle speed reaches the second set value 32 K m/h (e.g. LO
Km/h) or less. (Step P2o).

Here, the set value S2 means that the engine is R2r in low gear.
Select the lowest value at which the vehicle can travel when rotating at a speed of pm. If the vehicle speed is determined to be 32 or less in step P2o, it is determined that the vehicle speed sensor is abnormal (step P2 t
), generates an abnormality alarm.

(Step P22) (3) When it is determined that both the engine rotation sensor and the vehicle speed sensor are normal (Step P23), automatic engine stop/restart control is started (Step P24).

After the process of step P24 is completed, the fifth
Returning to the process shown in FIG. In this case, in step F'ts, the second set value R2rp
By waiting until the engine speed increases to m, it is possible to avoid frequent automatic engine stop/restart control within a short distance.

Note that the alarm mode 1 when the clutch switch is abnormal in the flowchart of Fig. 5 (Part 1), the alarm mode 2 when the engine rotation sensor is abnormal and the alarm mode 3 when the vehicle speed sensor is abnormal in Fig. 5 (Part 2) , different alarm patterns are set for each so that it can be determined which alarm mode is being executed.

In the above explanation, the set values R1, R of the engine rotation speed are
2 rpm, vehicle speed setting value S1. Since S2Km/h can be changed, even if the gear ratio of the applicable vehicle is different, it can be applied by changing these set values. Furthermore, the device of the present invention can be used as an engine automatic stop/restart control device.
It can be applied to determining control start conditions for a control device that uses a vehicle speed sensor and an engine rotation sensor.

FIG. 6 is a flowchart of the engine automatic stop/restart control section according to the present invention. Next, this flowchart will be explained.

(1) Turn on the power switch 2 and self-diagnosis switch 15
If the switch is on, the process proceeds to the self-diagnosis processing mode (steps Q1 and Q2). If the switch is off, the control start conditions explained in the flowchart of Fig. 5 (Part 2) are met. Determine whether the conditions are met, and issue an alarm if the control start conditions are not satisfied (steps Q5 and Q4). (2) If the control start conditions are met, various sensors will always be abnormal while driving. If there is no abnormality, it is determined whether the engine stop conditions are satisfied (steps Q5 and Q6).

Please check the following items for engine stop conditions.

(a) The driver has taken his foot off the clutch pedal.

(b) The transmission is placed in neutral.

(C) The vehicle speed is O or less than a predetermined value r.

(d) The engine speed is below the idling speed.

(e) The air tank pressure is normal.

(f) The lighting lamps are not lit.

If the conditions for the above items are met, the engine is stopped (step Q?). At this time, if there is an abnormality in the engine or other problems, a g alarm will be issued (step QB
, Q9), if normal, predetermined control of the air conditioner or heater is performed as necessary (step Q1o). While the engine is stopped, restart instructions and warnings may be issued as necessary (steps Qll and Q12). (3) To restart the engine, (a) the driver depresses the clutch pedal. To be.

(b) The transmission is placed in neutral.

(C) The engine must be stopped.

Step Q+5) to check whether the three-line property is satisfied; if the restart conditions are satisfied, restart the engine (Step Q14); and perform predetermined control of the air conditioner or heater (Step Q]7).

(4) If the engine restart signal is output to the starter and the engine does not restart even after the set time has elapsed, it is determined that the engine is abnormal and a warning is issued (steps Q15 and Q16).

In the present invention, τ also generates an alarm when the engine and stopper do not operate even if a stop signal t14= or a start signal is output to the engine stopper, and when the battery output drops below a set value.

(5) Displaying various items such as the number of times the starter is used, the fuel efficiency effect, the number of times the engine is stopped, etc. After detecting the condition and confirming that the vehicle is running, it determines whether the engine rotation sensor and vehicle speed sensor are malfunctioning, and if an abnormality occurs in the sensor, an alarm is generated, and both the engine rotation speed and vehicle speed are detected. Since the automatic engine stop Φ restart control is performed only when the engine is detected, it is no longer possible to misidentify the detection of a surge pulse due to noise as a vehicle speed pulse even though the vehicle is in a stopped state. In addition, if either the engine rotation sensor or the vehicle speed sensor is malfunctioning, a warning is generated, which makes it clear which sensor is malfunctioning and prompts the driver to take prompt action.Furthermore, in this case, the engine automatically stops.・Since restart control is not performed,
Safety is increased.

[Brief explanation of drawings]

FIG. 1 is a schematic block diagram of a conventional engine automatic stop/restart device, and FIG. 2 is a schematic block diagram of a conventional engine automatic stop/restart device.
A schematic block diagram of the restart control device, FIGS. 3 and 4 are explanatory diagrams, and FIGS. 5 to 6 are flowcharts. l...Electronic control device 2...Battery switch 3...
Heavy speed sensor 4... Engine rotation sensor 5... Neutral switch 6... Clutch switch 7... Air tank pressure switch 8... Room lamp switch 9... Headlight switch 10... Fog lamp switch 11 ... Air conditioner main switch 12 ... Heater switch 13 ... Starter switch 14 ... Starter engagement coil terminal 15 ...
・Self-diagnosis switch 16...RAM erase switch 17...Engine stopper 18...Starter 19...Heater fan 20...
...Heater 21...Warning device 22...Display device Patent applicant: Isui Jizansha Co., Ltd. Representative: Patent attorney Minoru Tsuji (1 other person) Figure 1, Figure 5, No. 2)

Claims (1)

[Claims] In systems that automatically stop and restart the engine when signals from sensors that detect the operating status of each part of a heavy vehicle and the operating status of the engine meet predetermined conditions, the operating status of the clutch and transmission is detected and the vehicle After confirming that the engine is running, it is determined whether the engine rotation sensor and vehicle speed sensor are malfunctioning. If both sensors are operating normally and both engine rotation and vehicle speed are detected, automatic engine stop/restart control is started and the engine is stopped. An automatic engine stop/restart control device that issues an abnormality alarm when either rotation or vehicle speed is not detected.