JPS59211728A - Fuel cassette unit - Google Patents

Abstract

PURPOSE:To prevent an engine from stopping by immediately intercepting the cutting of fuel at the time of braking or in case the deceleration is over a fixed value. CONSTITUTION:A brake sensor 10 is a switch to be on when a driver gives a stepping force onto a brake pedal and off in other cases. An engine revolution speed sensor 101 and a car speed sensor 104 detect the case where the deceleration is over a fixed value. At the time of the braking or when the decelerating is over the fixed value as said above, the cutting of fuel is immediately intercepted, and fuel injection is restarted.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field The present invention relates to a fuel cut device for a vehicle engine combined with a continuously variable transmission.

(b) Prior art The present applicant has filed Japanese Patent Application No. 57-213970 entitled "Fuel cut device for electronic engine control device for automobiles" (1982).
(filed on December 8, 2013) disclosed the following fuel cut device. That is, a device that detects the gear ratio and vehicle speed of a continuously variable transmission, and executes a fuel cut to stop the fuel supply when the gear ratio and vehicle speed meet predetermined conditions and the engine is in an idling state. It is. This device makes it possible to save fuel by stopping the supply of fuel to the engine during relatively high-speed engine braking conditions.

However, the above fuel cut device judges whether to execute fuel cut based on the vehicle speed and gear ratio, so if, for example, the brakes are applied and the speed suddenly decelerates, the fuel cut may be canceled. There was a problem in that the engine may stop due to a delay in the engine operation.

In other words, if the vehicle suddenly decelerates from the driving state where the fuel cut was executed, even though the vehicle speed rapidly decreases,
Continuously variable transmissions have a time delay in speed change response, so the gear ratio does not immediately reach the value corresponding to the vehicle speed, and the fuel cut continues to be executed based on the gear ratio with delayed response. , the engine stops because the fuel supply is not restarted even though the vehicle speed has decreased.

(C) Object of the Invention The object of the present invention is to provide a fuel cut device that immediately restarts fuel supply during rapid deceleration and does not cause engine stoppage.

(D) Structure of the Invention The present invention provides that when it is detected that the brakes are being applied or that the deceleration of the vehicle is greater than or equal to a predetermined value, the system immediately Configure the fuel cut device so that the fuel supply is resumed when That is, the fuel cut device according to the present invention has the following features:
An engine no-load detection device that detects an idling state of the engine, at least one of an engine rotational speed detection device and a vehicle speed detection device, and a brake operation detection device that detects activation of a brake or a deceleration of a vehicle. a deceleration detection device; and a fuel cut condition determining means for outputting a fuel cut signal to stop the fuel supply when the signals inputted from each of the above devices meet a predetermined condition;
It is made up of.

(e) Examples Examples of the present invention will now be described with reference to FIGS. 1 to 7 of the accompanying drawings.

(First Embodiment) FIG. 1 shows a block diagram of a fuel gutter device according to a first embodiment of the present invention. The control device 200 that controls the operation of the fuel injector 110 of the engine and the variable speed control motor 111 of the continuously variable transmission includes an engine rotation speed sensor 101, an air flow meter 102. Signals from a throttle opening sensor 103, a vehicle speed sensor 104, an idle sensor 105, a brake sensor 106, an engine coolant temperature sensor 107, a start switch 108, and a lever position detection sensor 112 of a shift operation mechanism are input. The control device 200 mainly has three functions. That is, the function controls the operation of the fuel injector 110 during normal driving to supply a predetermined amount of fuel to the engine, and controls the speed change control motor ill of the continuously variable transmission so that a predetermined gear ratio is achieved according to the driving conditions. This is a fuel cut function that stops the operation of the fuel injector 110 and stops the supply of fuel under predetermined operating conditions.

First, normal control of the fuel injector 110 is performed as follows. Engine speed sensor 1
01 detects the engine rotation speed, and an air flow meter 102 measures the intake air amount of the engine, and these signals are input to the basic calculation circuit 201. Basic calculation circuit 2
01 calculates a basic fuel injection pulse width based on the engine rotation speed and intake air amount, and corrects this by a calculation circuit 2O.
Output to 2. The correction calculation circuit 202 corrects the basic fuel injection pulse width based on the signals from the engine coolant temperature sensor 107 and the start switch 108 (and other correction manual power 100 as necessary), and uses it as an output pulse. The output pulse calculated by the correction calculation circuit 202 is sent to the cut switch 203 and the amplifier 2, which are normally on.
04 to the fuel injector 110. By doing this, the fuel injector 11
0 injects a predetermined amount of fuel into the cylinders of the engine based on the output pulse.

Control of the speed change control motor 111 of the continuously variable transmission is performed as follows. Signals from the throttle opening sensor 103 and the vehicle speed sensor 104 are input to the speed ratio calculation circuit 210, and based on these signals, the speed ratio calculation circuit 210 sets the operating state of the engine to, for example, a state with the lowest fuel consumption rate. 6. Calculates the gear ratio, sends this gear ratio signal to the gear change control motor 111 via the gear change motor drive circuit 211, and controls the operation of the gear change control motor 111 so that the continuously variable transmission has a predetermined gear ratio. The position of the lever of the speed change operation mechanism of the continuously variable transmission (this corresponds to the speed ratio of the continuously variable transmission) is detected by the lever position detection sensor 112 of the speed change operation mechanism, and the signal is sent to the speed ratio calculation circuit. 210 has been feedback back.

Fuel cut control for stopping the operation of the fuel injector 110 and stopping the supply of fuel is performed as follows. Signals from the engine speed sensor 101 , vehicle speed sensor 104 , idle sensor 105 , brake sensor 106 , and engine coolant temperature sensor 107 are input to the fuel cut condition determining means 212 . Note that the fuel cut condition determining means 212 can be configured by a normal analog circuit, but a microcomputer may also be used. The idle sensor 105 is a switch that is turned off when the driver applies pedal force to the accelerator pedal, and turned on in other cases.

The brake sensor 106 is a switch that is turned on when the driver applies pedal force to the brake pedal, and is turned off in other cases. Further, the engine coolant temperature sensor 107 is a sensor that detects the temperature of the engine coolant. The fuel cut condition determining means 212 sends a fuel cut signal to the cut switch 203 when these input signals meet predetermined conditions, turns it off, and prevents the correction calculation circuit 202 from transmitting the output pulse to the amplifier 204. do. When the cut switch 203 is turned off,
The fuel injector 110 becomes inactive, and the supply of fuel is stopped.

Next, specific judgment conditions in the fuel cut condition judgment means 212 will be explained. FIG. 2 shows the conditions for determining whether or not a fuel cut signal should be output, which is performed by the fuel car condition determination means 212. There are seven cases A to G depending on the combination of signals from the engine coolant temperature sensor 107, the idle sensor 105, the engine speed sensor toi, and the brake sensor 106.

First, in the case of A, B, D, F, and G, the fuel cut signal is not output. Condition A is a case where the idle sensor 105 is off. In this case, fuel cut is not executed regardless of other conditions. In this case, it is natural that the driver intends to accelerate. Next, condition B is
This is the case when the idle sensor 105 is on but the engine rotational speed is 90 ORPM or less. In this case, fuel power is not cut regardless of the engine coolant temperature and the brake sensor 106(7) signal. This is because the engine rotational speed is low, so if the fuel supply is stopped, the engine may stop. The condition is that the idle sensor 105 remains on for a predetermined period of time (for example, 0.5 seconds) after it was turned on, the engine rotation speed is 90 ORPM or more, and the brake is used. be. This condition corresponds to a state in which the vehicle is decelerating by stepping on the brake while driving at a relatively high speed. In this case as well, fuel cut is not executed. This is because if a fuel cut is performed, resumption of fuel supply may be delayed in the event of rapid deceleration. Condition F is the same as Condition F, but it is within the predetermined time mentioned above after the idle sensor 105 is turned on from off, and in this case as well, the fuel is not cut because the brake is being depressed.

After all, if the brake is being depressed, fuel cut is not executed regardless of other conditions. Condition G is water temperature 6.
This is the case when the temperature is below 0°C. In this case, since the engine has just been started and has not yet been warmed up, the fuel cut is not executed regardless of other conditions.

Next, in the case of conditions C and E, a fuel cut signal is sent to the cut switch 203 to stop the fuel supply. Condition C is a case where the engine cooling water temperature is 60 to 130°C, the idle sensor 105 is continuously on for more than the predetermined time mentioned above, the engine rotation speed is 90 ORPM or more, and the brake is not depressed. It is. This driving condition is, for example, when the vehicle is traveling on a gentle downhill slope while using engine braking. In this case, fuel supply is stopped when the vehicle speed is 40 km/h or higher, and fuel injection is restarted when the vehicle speed decreases to 20 km/h. Condition E is an engine coolant temperature of 60 to 1
The temperature is 30°C, the engine rotation speed is 800 rpm or more, the vehicle is traveling at a speed of 30 km/h or more without using the brakes, and the above-mentioned predetermined time has passed since the idle sensor 105 was turned on. . Note that condition C is the same for vehicle speeds of 40 km/h or higher, so condition E has meaning only for vehicle speeds of 30 km/h and above.
This is a case where the idle sensor 105 is switched from off to on during a speed of 40 km/h. In the case of this condition E, the fuel supply is also stopped, and the fuel supply is restarted when the vehicle speed decreases to 20 km/h. In this way, compared to condition C, when the idle sensor 105 is initially turned on from off, the fuel supply is stopped more frequently.

FIG. 3 is a diagram showing the state of the idle sensor signal, the vehicle speed, the engine rotation speed, and the state of the fuel cut signal under condition C and condition C. In FIG. 3, the solid line indicates condition C (ie, when the brake is not used), and the broken line indicates condition D (ie, when the brake is used). When the brake is not used, the engine rotational speed remains approximately constant. Also,
Immediately after turning on the idle sensor 105, the vehicle speed is 2.
Fuel supply is stopped until the distance drops to 0 km. On the other hand, when the brakes are used, the vehicle speed decreases rapidly, but there is a time delay before the gear ratio of the continuously variable transmission responds to this, so the vehicle speed decreases while the gear ratio remains small, and the engine speed decreases. The speed also decreases rapidly. However, in this case, since the fuel cut is not performed, the engine will not stop due to a delay in canceling the fuel cut.

(Second Embodiment) The configuration of the second embodiment is similar to the block diagram shown in FIG. However, the determination conditions used by the fuel cut condition determining means 212 are as shown in FIG. Conditions A, B, C, E, and G in FIG. 4 are exactly the same as those shown in FIG. 3, so their explanation will be omitted. Conditions and F are such that fuel is cut even when the brakes are applied. However, in this case, the engine rotational speed and vehicle speed for performing the fuel cut are set higher than conditions C and E, respectively, to prevent the engine from stopping. By doing this, even when the vehicle is decelerated, fuel is cut and fuel injection is restarted at a relatively high vehicle speed, thereby preventing the engine from stopping. That is, this second
In this embodiment, fuel consumption is reduced by cutting fuel as much as possible even when the brake is used.

(Third example) FIG. 5 shows a third embodiment of the present invention as a block diagram.

The configuration shown in FIG. 5 removes the brake sensor 106 in FIG. 1 and replaces it with a deceleration calculation circuit 213.
It has been established. The rest of the structure is the same as that in FIG. 1, so the same reference numerals will be used and the explanation will be omitted. A signal from the vehicle speed sensor 104 is input to the deceleration calculation circuit 213, and the deceleration calculation circuit 213 differentiates this signal to calculate the deceleration of the vehicle. The result is input to the fuel cut condition determining means 212.

FIG. 6 shows the fuel cut condition determining means 212 of the third embodiment.
The judgment conditions are shown below. In FIG. 6, the brake term in FIG. 2 is replaced with deceleration, and the other parts are the same as in FIG. 2. In the case of this third embodiment, the condition E
and F, it is determined whether the deceleration is equal to or greater than a predetermined value.

Therefore, basically the same effect can be obtained as when the brake sensor is on or off, but in this case the actual deceleration is used, so the brakes are used relatively lightly. If so, a fuel cut is performed, and fuel consumption can be reduced more effectively. That is, in the first embodiment, the fuel cut is not performed even when the brake pedal is pressed with relatively weak force, but in the case of the third embodiment 1, the fuel cut is not performed even when the brake pedal is pressed with relatively weak force. Since the fuel power control is not activated only when a relatively large deceleration occurs as a result of the deceleration, the operating range of the fuel power control device is expanded accordingly.

Condition E is such that when the idle sensor 105 changes from OFF to ON, the fuel supply is easily stopped, and the deceleration is 5 km/h/see or higher and the engine rotation speed is 800 rpm or higher. ) conditions are attached. Condition F differs from condition E4 in that it has a large deceleration of 10 km/h.
This is to avoid fuel cut when the speed of 100 h/sec occurs.

(Fourth Embodiment) FIG. 7 shows the determination conditions of the condition determination means 212 of the fuel car according to the fourth embodiment of the present invention. The block diagram of this fourth embodiment is the same as that shown in Figure 5. In FIG. 7, the brake term in FIG. 3 is replaced with deceleration, and almost the same effect as in the second embodiment can be obtained. Since the condition is the deceleration instead of the brake number, the operating range of the fuel cut device is widened, as in the case of the third embodiment described above. (f) As described in detail of the invention, According to the present invention, in a fuel cut device provided in an engine of a vehicle equipped with a continuously variable transmission with a continuously variable gear ratio, an engine no-load detection device (in this embodiment, an engine no-load detection device for detecting an idling state of the engine) idle sensor 105), and at least one of the engine rotation speed detection device (engine rotation speed sensor 101) or the vehicle speed detection device (vehicle speed sensor 104) (in the embodiment, both are membranes, but either one and the gear ratio It is also possible to calculate the other from
brake sensor 106) or a deceleration detection device (deceleration calculation circuit 213) that detects the deceleration of the vehicle, and a fuel cut signal that stops fuel supply when the signals input from each of the above devices meet predetermined conditions. Since the fuel cut condition determining means (212) outputs the fuel cut condition determination means (212), the fuel cut is not performed when deceleration is performed or when the deceleration force is too high for a rapid turn. I) can be rubbed in a regular manner,
When the engine stops, 1/1 problem can be prevented from occurring. Note that when the deceleration of the vehicle is detected (the third embodiment and the fourth embodiment), the processing speed is higher than when the on/off state of the idle sensor is detected (the first embodiment and the second embodiment). , the operating range of the fuel cut device can be widened.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing the first embodiment of the present invention as a block diagram, Fig. 2 is a diagram showing the fuel cut judgment conditions in the fuel cut condition judgment means, and Fig. 3 is a diagram showing the fuel cut judgment conditions in the fuel cut condition judgment means. 4 is a diagram showing the vehicle speed, engine rotation speed, etc. during operation, FIG. 4 is a diagram showing fuel cut judgment conditions in the fuel cut condition judgment means of the second embodiment of the present invention, and FIG. FIG. 6 is a diagram showing the fuel cut determination conditions of the fuel car/ ) condition determination means in the third embodiment, FIG. 7 is a diagram showing the fuel cut determination conditions of the fourth embodiment of the present invention. It is a figure showing fuel cut judgment conditions in a condition judgment means. 100・e・correction input, 101・---engine speed sensor, 102・・air flow meter, 103−@
・Throttle opening sensor, 104...Vehicle speed sensor, 105...Fist idle sensor, 106...Brake sensor, 107ψ...Engine coolant temperature sensor,
No. 108 IIS start switch, 110... Fuel injector, 111... Speed change control motor, 11
2. Lever position detection sensor of fist shift operation mechanism, 20
0φ...control device, 201...basic arithmetic circuit, 202
...Correction calculation circuit, 203...Cut switch, 2
04... Amplifier, 210... Speed ratio calculation circuit, 21
1... variable speed motor drive circuit, 212... fuel car,
213.1. Deceleration calculation circuit. Patent applicant Nissan Motor Co., Ltd. Agent
Patent attorney Toshiyuki Miyauchi

Claims (1)

[Scope of Claims] 1. In a fuel cut device installed in an engine of a vehicle equipped with a continuously variable transmission with a continuously variable gear ratio, an engine no-load detection device for detecting a fitting state of the engine; At least one of an engine rotational speed detection device and a vehicle speed detection device; a brake operation detection device that detects that the brake has been applied or a deceleration detection device that detects vehicle deceleration; and signals input from each of the above devices. 5. A fuel cut device comprising: fuel cut condition determination means for outputting a fuel cut signal for stopping fuel supply when the fuel supply is under a predetermined condition. 2. The fuel cut determination means is a brake operation detection device, or
The fuel cut device according to claim 1, which does not output the fuel cut signal when a signal indicating that the brake is activated is inputted. 3. The fuel cut determining means does not output the fuel cut signal when a signal indicating that the deceleration is larger than a predetermined value is input from the deceleration detection device. cutting equipment. 4. If a signal indicating that the brakes are operating is input from the brake operation detection device, the fuel cut determination means determines whether the brakes are operating at the lower limit vehicle speed for starting fuel power and the vehicle speed for restarting fuel supply. 2. The fuel cut device according to claim 1, wherein the fuel cut rate is set higher than when no signal indicating this is input. 5. When the signal from the deceleration detection device indicates that the deceleration is larger than a predetermined value, the fuel cut determination means determines the fuel cut start lower limit vehicle speed and the fuel supply restart vehicle speed when the deceleration is smaller than the predetermined value. The fuel cut device according to claim 1, wherein the fuel cut device is made higher than the fuel cut device.