JPH051379B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fuel injection amount smoothing control method for a diesel engine, and particularly to a method for smoothing the engine rotational speed and the like, which is suitable for use in an electronically controlled diesel engine for automobiles equipped with a manual transmission. When determining the fuel injection amount according to the engine operating state including the access opening, the acceleration is smoothed in the direction of increasing the fuel injection amount to alleviate the acceleration shock.Fuel injection amount smoothing control for a diesel engine Concerning improvements in methods.

In diesel engines, especially electronically controlled diesel engines for automobiles with manual transmissions, in order to alleviate acceleration shock during acceleration,
A so-called fuel injection amount smoothing control is proposed, which performs a smoothing process in the direction of increasing the fuel injection amount and alleviates acceleration shock by limiting the amount of increase in fuel injection amount and accelerator opening during acceleration. has been done.

However, if this smoothing control is constantly activated, the amount of fuel injection will not be increased due to the drop in engine speed when the clutch is engaged for starting or shifting, and the engine speed will drop significantly after clutch engagement, causing the clutch to engage. There was a fear that it would be difficult to meet.

The present invention was made in order to solve the above-mentioned conventional problems, and it is possible to smoothly engage the clutch and improve the fuel injection amount of the diesel engine, thereby improving the driving feeling during clutch engagement. The purpose is to provide a better control method.

In the present invention, when determining the fuel injection amount according to the engine operating state including the engine rotation speed and the accelerator opening degree, during acceleration, smoothing processing is performed in the direction of increasing the fuel injection amount to alleviate the acceleration shock. In the fuel injection amount smoothing control method for a diesel engine, as shown in Figure 1, there are steps to determine whether the clutch is disengaged, and if the clutch is not disengaged, a set time elapses after the clutch is engaged. The procedure for determining whether the set time has elapsed and if the clutch is disengaged or the set time has not elapsed since the clutch was engaged.
The above object is achieved by including the step of prohibiting the smoothing process in the direction of increasing the fuel injection amount.

In the present invention, when performing the smoothing process in the direction of increasing the fuel injection amount during acceleration, if the clutch is disengaged or the set time has not elapsed since the clutch was engaged, the smoothing process in the direction of increasing the fuel injection amount is performed. Since the smoothing process is prohibited, a large drop in engine speed during and after clutch engagement is prevented, and clutch engagement can be performed smoothly.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of an electronically controlled automobile diesel engine equipped with a manual transmission will be described in detail with reference to the drawings, in which the fuel injection amount smoothing control method for a diesel engine according to the present invention is adopted.

As shown in FIG. 2, this embodiment includes a drive shaft 14 that rotates in conjunction with the rotation of the output shaft of a diesel engine 10, and a feed pump 16 (a feed pump 16) fixed to the drive shaft 14 for pumping fuel. Figure 2 is
The drive shaft 14 rotates by a predetermined crank angle due to the rotational displacement of the fuel pressure regulating valve 18 for adjusting the fuel supply pressure and the gear 20 fixed to the drive shaft 14 (showing a state rotated by 90 degrees). A rotational speed sensor 22 consisting of an electromagnetic pickup, for example, for measuring the time required for the rotational speed of the diesel engine 10, a roller ring 24 for controlling the fuel injection timing, and a roller ring 24 for driving the roller ring 24. A timer piston 26, a timing control valve 28 for controlling the position of the timer piston 26, a timer position sensor 30 comprising, for example, a variable inductance sensor for detecting the position of the timer piston 26, and a timer position sensor 30 for controlling the fuel injection amount. spill ring 32, the spill ring 3
2, a plunger 34a, a compression spring 34b, a coil 34c, and a coil case 34d.
a spill actuator 34 consisting of a spill actuator 34, a spill position sensor 36 consisting of, for example, a variable inductance sensor for detecting the position of the spill ring 32 from the displacement of the plunger 34, and a fuel cut solenoid 38 for cutting off fuel when the engine is stopped. , plunger 40 and delivery valve 4
2, an injection nozzle 44 for injecting the fuel discharged from the delivery valve 42 of the fuel injection pump 12 into the auxiliary combustion chamber of the diesel engine 10, and an intake pipe 46 for injecting the fuel An intake pressure sensor 48 for detecting the pressure of the intake air, an intake temperature sensor 50 for similarly detecting the temperature of the intake air, and the cylinder block 10a of the diesel engine 10.
A water temperature sensor 52 for detecting the engine cooling water temperature and an accelerator sensor 54 for detecting the depression angle of the accelerator pedal 53 operated by the driver (hereinafter referred to as accelerator opening degree).
and a clutch pedal 56 that is also operated by the driver.
a clutch switch 57 for detecting the on/off state of the clutch from the depressed state of the clutch, an accelerator opening detected from the output of the accelerator sensor 54, an engine rotational speed detected from the output of the rotational speed sensor 22, and the cooling water temperature sensor. The timing control valve 28 determines the target injection timing and calculated injection amount based on the engine cooling water temperature detected from the output of the fuel injection pump 12 so that the calculated injection amount of fuel is injected from the fuel injection pump 12 at the target injection timing.
The electronic control unit (hereinafter referred to as ECU) 58 controls the subil actuator 34 and the like.

In the figure, 25 is a cam plate, and 33 is a tension spring.

The ECU 58, as shown in detail in FIG.
A central processing unit (hereinafter referred to as
(referred to as CPU) 59, the output of the cooling water temperature sensor 52 which is input via a buffer 60, and the intake temperature sensor 50 which is input via a buffer 62.
output, the output of the intake pressure sensor 48 inputted via the buffer 64, the output of the accelerator sensor 54 inputted via the buffer 66, and the sensor drive frequency signal of the output of the sensor drive circuit 68. The timer position sensor 30 is driven by the output of the spill position sensor 36 inputted via the detection circuit 70 and the sensor drive frequency signal outputted from the sensor drive circuit 72, and inputted via the sensor signal detection circuit 74. A multiplexer 76 for sequentially taking in the output etc., an analog-to-digital converter (hereinafter referred to as an A/D converter) 78 for converting the analog signal output from the multiplexer 76 into a digital signal, and the A/D converter 78 for converting the analog signal output from the multiplexer 76 into a digital signal.
An input/output port 80 for receiving the D converter 78 output into the CPU 59, an input/output port 84 for receiving the clutch switch 57 output via a buffer 82, and the rotational speed sensor 22.
A waveform shaping circuit 94 for shaping the output and inputting it into the CPU 59, and a clock generation circuit 102.
and a backup random access memory (hereinafter referred to as
Random accelerator memory (hereinafter referred to as RAM) 104 including backup RAM (hereinafter referred to as RAM)
, a read-only memory (hereinafter referred to as ROM) 106 for storing control programs and various data, etc., and a drive circuit 108 for driving the timing control valve 28 according to the calculation results in the CPU 59. A drive circuit 109 for driving the FCV 38 according to the calculation result in the CPU 59 and a digital-to-analog converter (hereinafter referred to as a D/A converter) 110 convert the output of the CPU 59 into an analog signal and the spill. It is comprised of a servo amplifier 112 and a drive circuit 114 for driving the spill actuator 34 according to the deviation from the position sensor 36 output.

The action will be explained below.

Calculation of the fuel injection amount in this embodiment is performed according to a flowchart as shown in FIG. That is,
First, in step 110, a target value for the fuel injection amount is calculated in accordance with the engine rotational speed determined from the output of the rotational speed sensor 22, the accelerator opening degree determined from the output of the accelerator sensor 54, and the like. Next, the process proceeds to step 112, where the previous fuel injection amount and the currently calculated target fuel injection amount are compared to determine whether or not the fuel injection amount is increasing. If the result of the determination is positive, that is, if it is determined that the vehicle is being accelerated, the process proceeds to step 114, where it is determined whether or not the clutch is disengaged, depending on the state of the clutch switch 57. If the result of the determination is negative, the process proceeds to step 116, where it is determined whether a set time, for example 3 seconds, has elapsed since the clutch was turned on. If the determination result is positive, the process proceeds to step 118, and, for example, the fuel injection amount is gradually increased by a set increase amount from the previous fuel injection amount to the target value, thereby increasing the fuel injection amount. Perform smoothing processing.

On the other hand, the determination result in step 112 is negative,
When it is determined that the acceleration is not in progress, step 114 mentioned above
When the judgment result of step 116 is positive and it is judged that the clutch is disengaged, or when the judgment result of step 116 is negative and it is judged that 3 seconds have not elapsed since the clutch was turned on. Sometimes, the fuel injection amount is controlled so as to match the target value, so that smoothing processing in the direction of increasing the fuel injection amount is not performed.

In this way, the clutch is broken or
If the set time has not elapsed since the clutch was engaged, by prohibiting the smoothing process in the direction of increasing the fuel injection amount, it is possible to prevent a large drop in engine speed during and after clutch engagement. , smooth clutch meat is possible.

In this embodiment, since the determination of whether the vehicle is accelerating is made based on the increase/decrease state of the fuel injection amount, the acceleration determination is easy. Note that the method for determining acceleration is not limited to this, and for example, it is also possible to determine acceleration based on the increase/decrease state of the accelerator opening.

In addition, in the above embodiment, the smoothing process is
Although the smoothing process is performed on the fuel injection amount, the target to which the smoothing process is performed is not limited to this, and it is also possible to perform the smoothing process on the accelerator opening degree.

In the above embodiments, the present invention was applied to an electronically controlled diesel engine for automobiles equipped with a manual transmission, but the scope of application of the present invention is not limited thereto, and can be applied to general diesel engines as well. The applicability is clear.

As explained above, according to the present invention, it is possible to prevent the engine rotation from greatly decreasing during and after clutch engagement. Therefore, it is possible to smoothly engage the clutch, and the driving feeling at the time of clutch engagement can be improved, which is an excellent effect.

[Brief explanation of the drawing]

FIG. 1 is a flowchart showing the gist of a fuel injection amount smoothing control method for a diesel engine according to the present invention;
FIG. 2 is a sectional view, including a partial block diagram, showing the configuration of an embodiment of an electronically controlled automobile diesel engine equipped with a manual transmission to which the present invention is adopted, and FIG. 3 is a sectional view of the embodiment described above. Figure 4 is a block diagram showing the configuration of the electronic control unit used in
Similarly, it is a flowchart showing the main part of a routine for calculating the fuel injection amount. DESCRIPTION OF SYMBOLS 10... Diesel engine, 12... Fuel injection pump, 22... Rotation speed sensor, 54... Accelerator sensor, 57... Clutch switch, 58... Electronic control unit (ECU).

Claims (1)

[Claims] 1 When determining the fuel injection amount according to engine operating conditions including engine speed and accelerator opening, a diesel engine is designed to smooth out the fuel injection amount in the direction of increase during acceleration to alleviate acceleration shock. In the fuel injection amount smoothing control method, there is a procedure for determining whether the clutch is disengaged, a procedure for determining that a set time has elapsed since the clutch was engaged if the clutch is not disengaged, and a procedure for determining that a set time has elapsed since the clutch was engaged. If the clutch is disconnected or a set time has not elapsed since the clutch is engaged, the fuel injection amount adjustment method for a diesel engine is characterized by including a step of prohibiting annealing processing in the direction of increasing the fuel injection amount. Better control method.