JPH08121231A - Controller of fuel injection pump of diesel engine - Google Patents

Abstract

PURPOSE: To avoid deterioration of the PM discharging quantity in a transition period, to be generated caused by control delay of the ignition timing. CONSTITUTION: The flow rate of fuel to be made to leak from a high-pressure chamber on one end of a timer piston to the lower-pressure side by being bypassed is adjusted by the driving amount to be applied to a timing control valve 101. At least the basic injection timing IT corresponding to the engine speed Ne is calculated by a calculating means 102, the basic injection timing IT is corrected to the advance side by the correction amount ΔIT in acceleration, and the command injection timing ITso is calculated by a calculating means 104. The actual injection timing ITi is calculated from the detected value of a timer piston position sensor 105 by a calculating means 106, and the driving amount to be applied to the timing control valve 101 is feedback- corrected by a correcting means 107, so that this actual injection timing ITi may match the command injection timing ITso.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a diesel engine fuel injection pump.

[0002]

2. Description of the Related Art In a diesel engine, there is an ignition delay period between the time fuel is injected into a combustion chamber and the time it is ignited. The period is substantially constant regardless of the engine speed. Since it is necessary to advance the injection timing, the mechanical distribution type injection pump has a timer mechanism, and the fuel injection amount,
The distributed injection pump, which has electronically controlled fuel injection timing, is equipped with a timing control valve that can adjust the amount of leak from the high-pressure chamber of the timer piston to the low-pressure side. See the section on injection).

In the electronically controlled distribution type injection pump, as shown in FIG. 4, when the hydraulic pressure applied to the high pressure chamber 28 of the timer piston 26 is leaked to the low pressure chamber 30 side through the timing control valve 33, the timer piston position is changed. Is displaced to the high pressure chamber 28 side (that is, the retard angle side) in the figure, the injection timing can be arbitrarily controlled by controlling the duty value given to the timing control valve 33.

[0004]

By the way, at the time of acceleration, it is necessary to advance the injection timing with good response, but in reality there is a control delay of the injection timing due to the operation delay of the timing control valve and the timer piston. PM emissions during acceleration tend to increase. When a so-called exhaust gas recirculation (hereinafter referred to as EGR) device that recirculates a part of the exhaust gas into the intake air is provided to reduce NOx in the exhaust gas, a control delay of the EGR is added, and the PM emission amount further increases. . This is because the injection timing does not advance responsively, and the EGR gas remains due to the EGR control delay to deteriorate combustion. Therefore, the actual injection timing at the time of acceleration and the EGR rate change as shown by the black arrow in the characteristic at the time of acceleration shown in FIG.

Although the above is during acceleration, a control delay of the injection timing occurs during deceleration, and due to this control delay, not only the PM emission amount but also the NOx emission amount increases during deceleration.

Therefore, the present invention introduces a correction amount commensurate with the control delay of the injection timing, and by advancing the injection timing during acceleration by the correction amount, and by retarding the injection timing during deceleration, The purpose is to avoid the deterioration of the PM emission amount at the transition time caused by the control delay of the injection timing.

[0007]

The first invention, as shown in FIG. 37, is a drive amount given to the timing control valve 101 by the fuel flow rate which is bypassed from the high pressure chamber at one end of the timer piston and leaked to the low pressure side. A distribution type injection pump adjusted by (for example, a duty value),
At least the basic injection timing I according to the engine speed Ne
A means 102 for calculating T, and a command injection timing I by correcting the basic injection timing IT to the advance side by a correction amount ΔIT during acceleration.
A means 104 for calculating Tso, a sensor 105 for detecting the timer piston position, a means 106 for calculating an actual injection timing ITi from a detection value of the timer piston position sensor 105, and an actual injection timing ITi for the command injection timing. A means 107 for feedback-correcting the drive amount given to the timing control valve 101 is provided so as to match ITso.

According to a second aspect of the present invention, in the first aspect of the present invention, from the load change amount per unit time (for example, the accelerator opening change amount TACC per unit time), it is judged that the vehicle is accelerating for the first time and the engine speed from the previous time is determined. When there is no rise, the advance angle correction during acceleration is not performed.

A third aspect of the invention is the fuel cell system according to the first or second aspect of the invention, in which the set load of the return spring of the regulating valve is switchable, and the actual injection timing ITi and the command injection timing ITso are set during acceleration. Difference ITh
Is greater than or equal to a predetermined value ITss, the set time of the return spring is switched to a larger side for a specified time Tts.

In a fourth aspect based on the first or second aspect, the set load of the timer spring is switchable, and the difference ITh between the actual injection timing ITi and the command injection timing ITso is predetermined during acceleration. When the value is ITss or more, the set time Tts2 is switched to the side where the set load of the timer spring becomes smaller.

In the fifth aspect of the invention, as shown in FIG. 38, the flow rate of fuel that is bypassed from the high pressure chamber at one end of the timer piston and leaked to the low pressure side depends on the drive amount (eg, duty value) given to the timing control valve 101. A distribution type injection pump to be adjusted, a means 102 for calculating a basic injection timing IT corresponding to at least the engine speed Ne, and the basic injection timing I with a correction amount ΔIT during deceleration.
Means 111 for calculating the command injection timing ITso by correcting T to the retard side, sensor 105 for detecting the timer piston position, and timer piston position sensor 1
Means 10 for calculating the actual injection timing ITi from the detected value of 05
6 and the actual injection timing ITi is the command injection timing ITs.
Means 1 for feedback-correcting the drive amount given to the timing control valve 101 so as to coincide with o
07 are provided.

According to a sixth aspect of the present invention, in the fifth aspect of the present invention, when it is judged from the load change amount per unit time that the engine is decelerating for the first time, and there is no decrease in engine rotation from the previous time, the retard correction during the deceleration is performed. Do not do.

In a seventh aspect based on the fifth or sixth aspect, the set load of the return spring of the regulating valve is switchable, and the actual injection timing ITi and the command injection timing ITso are set during deceleration. Difference ITh
Is greater than or equal to a predetermined value ITss, the set time of the return spring is switched to the side where the set load becomes smaller for a specified time Tts.

In an eighth aspect based on the fifth or sixth aspect, the set load of the timer spring is switchable, and the difference ITh between the actual injection timing ITi and the command injection timing ITso is predetermined during deceleration. When it is equal to or greater than the value ITss, the specified time Tts2 is switched to the side where the set load of the timer spring increases.

In a ninth aspect based on any one of the first to eighth aspects, the correction amount ΔIT has a larger value as the engine speed Ne becomes lower.

A tenth invention is the invention according to any one of the first invention to the eighth invention, wherein the correction amount ΔIT is
The larger the load change amount per unit time, the larger the value.

An eleventh invention is the third or seventh invention, wherein the specified time Tts is a value that increases as the engine speed Ne decreases.

[0018]

According to the first aspect of the present invention, the advance angle speed at the time of acceleration is increased by advancing the injection timing by the correction amount ΔIT corresponding to the control delay at the time of acceleration in which the injection timing control delay occurs. Therefore, the PM emission amount during acceleration is effectively suppressed.

According to the second aspect of the present invention, the advance angle speed is not unnecessarily increased when the accelerator pedal is greatly depressed only for a moment, and the NOx emission amount is increased by the unnecessary increase in the advance angle speed. Is prevented.

In the third invention, the actual injection timing IT during acceleration
The difference ITh between i and the command injection timing ITso is a predetermined value ITss.
When it is larger than the above, it is switched to the side where the set load of the return spring of the regulating valve becomes large,
Since the pump internal pressure is higher than that before acceleration, the advance speed will not slow down even if rotation loss may occur during gear change during acceleration.

Also in the fourth invention, as in the third invention, even if a rotation drop occurs during gear change during acceleration, the advance speed is not slowed down. In the fourth invention, the timer is used. Since we are going to drive directly
The prescribed time can be made shorter than that in the third aspect of the invention when there is a rotation drop due to a gear change during acceleration.

In the fifth aspect of the invention, when the injection timing is decelerated, the injection timing is retarded by the correction amount ΔIT corresponding to the control delay, thereby increasing the retard speed during deceleration. It is possible to prevent both the PM emission amount and the NOx emission amount during deceleration due to the control delay from being deteriorated.

In the sixth aspect of the invention, the retard speed is not unnecessarily increased when the accelerator pedal is largely returned for a moment.

In the seventh aspect of the invention, the actual injection timing IT during deceleration
When i is delayed by a predetermined value ITss or more from the command injection timing ITso, the set load is switched so that the pump internal pressure is made lower than the steady state. Therefore, even if there is a temporary increase in rotation due to gear change during deceleration, the retard speed Never blunts.

In the eighth aspect of the invention, the actual injection timing IT during deceleration
When i is delayed from the command injection timing ITso by a predetermined value ITss or more, the set load of the timer spring is made higher than that in the steady state, so that the retarding speed is slowed even if there is a temporary increase in rotation due to gear change during deceleration. In addition, since the timer is directly driven, the specified time can be shortened as compared with the seventh invention.

In the ninth invention, the value of ΔIT is increased as the rotation speed becomes lower even if the degree of acceleration or the degree of deceleration is the same, so that the advance speed is not slowed down when accelerating from the low rotation range. Further, the retarding speed is not slowed down even during deceleration in the low speed range.

In the tenth aspect of the invention, since the value of ΔIT is increased as the load change amount per unit time increases, the target injection timing in consideration of the control delay of the injection timing is provided even during sudden acceleration or sudden deceleration. be able to.

In the eleventh aspect of the invention, the prescribed time Tts is increased as the engine speed Ne decreases, so that the pump internal pressure is increased without excess or deficiency according to the pump internal pressure immediately before acceleration, and the pump internal pressure immediately before deceleration. Accordingly, the internal pressure of the pump can be reduced without excess or deficiency.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an electronically controlled distributed fuel injection pump,
It is known.

First, the fuel is sucked from an inlet (not shown) of the pump body by a feed pump 3 driven by a drive shaft (connected to the engine output shaft) 2, and the fuel introduced into the pump chamber 5 operates. At the same time that the part is lubricated, it is sent to the high-pressure plunger pump 7 through the suction port 6.

The plunger 8 of the pump 7 is fixed to a cam disk 9 connected to the drive shaft 2,
The drive shaft 2 is driven via the joint 2A in synchronization with the engine rotation. The cam disk 9 has the same number of fiber cams 10 as the number of cylinders of the engine, and each time the face cam 10 gets over the rollers 12 arranged on the roller ring 11 while rotating, it reciprocates by a predetermined cam lift.

When the plunger 8 reciprocates while rotating in this way, the fuel sucked from the suction port 6 by this reciprocating motion is pumped from the distribution port 13 through the delivery valve 14 to the injection nozzle (not shown). It

On the other hand, the fuel injection amount is determined by the position of the control sleeve 16 which covers the cutoff port 15 formed in the plunger 8. For example, when the opening of the cutoff port 15 moves to the right side of the plunger 8 and crosses the right end of the control sleeve 16, the fuel that has been pressure-fed from the plunger high pressure chamber 7A to the distribution port 13 until then. , Cut-off port 1
Since it is released to the low pressure pump chamber 5 through 5, the pumping to the distribution port 13 is completed.

Therefore, when the control sleeve 16 is displaced relative to the plunger 8 in the right direction,
When the fuel injection end timing is delayed and the fuel injection amount increases, conversely, when the fuel injection end timing is delayed, the fuel injection end timing is advanced and the fuel injection amount decreases.

The control sleeve 16 is supported by a ball 23 eccentrically provided at the tip of a rotor (rotating shaft) 22 of a rotary solenoid (a kind of proportional solenoid) 21, and the control sleeve 16 is controlled according to the rotation angle of the rotor 22 shown in FIG. The position is displaced. As shown in FIG. 3, the rotational movement of the rotor 22 is converted into the linear movement of the control sleeve 16 in the left-right direction.

In FIG. 3, as the rotation angle of the rotor 22 in the clockwise direction increases, the control sleeve 16
Of the rotor 22 increases (the amount of fuel injection increases), the rotation angle of the rotor 22 in the clockwise direction is proportional to the duty value (ON time ratio per constant time) given to the rotary solenoid 21. I am trying to grow.

The fuel injection timing is adjusted by changing the relative position of the face cam 10 and the roller 12 by the roller ring 11.

The roller ring 11 is connected via a timer slide pin 25 to a timer piston 26 which is rotatable in the rotational tangential direction of the roller ring 11. As shown in FIG. 4, the fuel pressure in the pump chamber 5 is introduced into the high pressure chamber 28 on one end surface of the timer piston 26 that slides in the cylinder 27 through the passage 29, and the low pressure chamber 3 on the opposite side.
Although 0 is in communication with the suction side of the feed pump 3 and is in a state close to negative pressure, the elastic force of the spring 31 pushes back the timer piston 26.

When the fuel pressure in the pump chamber 5 rises as the engine speed increases, the timer piston 30 is pushed to the right in FIG. 4, thereby rotating the roller ring 11 in the direction opposite to the rotation of the cam disk 8. , It acts to relatively advance the injection timing. Face cam 10 of cam disk 9
When the vehicle rides on the roller 12, fuel is injected. Therefore, when the roller ring 11 is rotated in the direction opposite to the rotation direction of the cam disk 9, the roller 1 of the face cam 10 is rotated.
Therefore, the timing of riding on 2 becomes earlier, and the fuel injection timing with respect to the crank angle can be advanced.

However, the fuel pressure in the pump chamber 5 is
Since it increases linearly in proportion to the engine speed, the injection timing can basically only be advanced linearly in proportion to the engine speed. Therefore, if the fuel in the high pressure chamber 28 is leaked to the low pressure side by opening the timing control valve 33 provided in the bypass passage 32, the injection timing can be delayed even at the same rotation speed.
The leakage flow rate to the low pressure side is adjusted by the duty value (hereinafter referred to as TCV duty value) given to the timing control valve 33.

However, the TCV duty value is not the ON time ratio per constant time, but the OV per constant time.
FF time ratio. TCV duty value is 100%
(That is, the timing control valve 33 is at the fully closed position) and the maximum advance angle is obtained, and at 0% (the timing control valve 33 is at the fully open position), the minimum advance angle (the leakage flow rate to the low pressure side is maximum). OFF time ratio is 10
0% means that the timing control valve 33
Is in a non-energized state, and the timing control valve 33 is in the fully closed position in the non-energized state for fail-safe. For example, when the wiring to the timing control valve 33 is broken, the timing control valve 33 is in a fully closed state (that is, the same state as when the timing control valve 33 is not provided).

FIG. 5 is a control system diagram of the injection pump which is electronically controlled.

Control sleeve position sensor 38
Is attached integrally with the rotor 22 of the rotary solenoid 21 as shown in FIG. 2, and outputs a signal according to the rotation angle of the rotor 22. As shown in FIG. 4, the timer piston position sensor 39 converts the displacement amount of the timer piston 26 into a voltage value and outputs it.

The reference pulse (Ref signal) is one pulse per revolution of the injection pump, and the scale pulse is 36 pulses per revolution of the injection pump. These pulses from the injection pump and the sensor signals of the control sleeve position sensor 38 and the timer piston position sensor 39 detect the accelerator opening degree sensor 36,
Water temperature sensor 40, air conditioner switch 41, inhibitor switch 42 for detecting selector position of automatic transmission
Is input to an ECU (Electronic Control Unit) 35 together with a signal from the ECU, and the ECU 35, which is a microcomputer, controls both the drive amount given to the rotary solenoid 21 and the timing control valve 33.

The accelerator opening is actually obtained from the control lever position of the injection pump. It is said that the pump speed is calculated in the control unit 35 based on the Ref signal from the injection pump and the scale pulse, and the engine speed (twice the pump speed) Ne is further calculated from this pump speed. There is no end.

On the other hand, a known EGR control device is provided, for example, as shown in FIG. The example shown is for a vehicle with two-wheel drive and a manual transmission.

In FIG. 6, two three-way valves 51 and 53 are provided.
Is a valve that receives a signal from the ECU 35 and switches and introduces a constant negative pressure and an atmospheric pressure created by a vacuum pump. The atmospheric pressure is always introduced, but the EGR valve is energized by energizing one of the three-way valves 51. A constant negative pressure is introduced into 52 to open the EGR valve 52, and the energization of the other three-way valve 53 operates the diaphragm actuator 54 to close the throttle valve 55 to a predetermined opening. The ECU 35 controls the EGR amount in two stages, large and medium, for example, as shown in FIG. 7, based on the cooling water temperature, the accelerator opening, the rotation speed, and the air conditioner signal.

Although it is necessary to advance the injection timing with good response at the time of acceleration, in reality, there is a control delay of the injection timing, and a control delay of the EGR is also added, so PM
Emissions will increase significantly.

Here, the control delay of the injection timing depends on the ECU 3
5, the operation delays of the timing control valve 33 and the timer piston 26 are added to the calculation delay of 5. Further, the control delay of EGR includes a calculation delay of the ECU 35, operation delays of the three-way valves 51, 53, the EGR valve 52, and the diaphragm actuator 54, and a gas flow delay of EGR gas and intake air.

Due to the control delay of the injection timing and the control delay of the EGR, the characteristics of the PM emission amount at the time of acceleration with respect to the injection timing / EGR shown in FIG.
This means that the GR rate follows the region where the PM emission amount is large, as indicated by the black arrow.

To deal with this, the ECU 35 cuts the EGR during acceleration and advances the injection timing by an amount that corresponds to the control delay of the injection timing. By this operation, in the acceleration characteristic of FIG. 8, the actual injection timing and the EGR rate are traced as shown by arrows different from the black arrows, so that it is possible to prevent a significant deterioration of the PM emission amount during acceleration.

Regarding EGR, the three-way valves 51, 5
3, EGR valve 52, diaphragm actuator 54
Even if the response characteristic of is improved, since the EGR gas remains in the intake pipe due to the gas flow delay between the EGR gas and the intake air, the intake air flow rate is small especially immediately after the start acceleration, so that the response of the EGR cut is reduced. It won't be fast.
However, as can be seen from the acceleration characteristics of FIG. 8, if the injection timing can be advanced with good response without cutting the EGR, a significant deterioration of the PM emission amount can be prevented.

FIG. 9 is a block diagram showing the outline of the injection timing control, and FIG. 10 is a flow chart showing the details of the control, which will be explained below with reference to the flow chart.

The main routine of FIG. 10 is executed in a fixed cycle (for example, 4 ms) or in synchronization with the Ref signal.

In step 1, the engine speed Ne
[Rpm], fuel injection amount Q [mg / st], cooling water temperature T
Read w [° C]. It should be noted that the fuel injection amount Q is a value obtained by referring to the map having the content shown in FIG. 11 from the rotation speed Ne and the accelerator opening degree ACC in another routine (not shown) of the injection amount control. However, at the time of idling, the injection amount may be increased and corrected depending on the battery voltage, the operating state of the air conditioner, and the like.

In step 2, the fuel injection amount Q and the rotational speed N
The basic injection timing is obtained from e by referring to the map, and this is entered in the variable ITs2 [mm]. The contents of this map are shown in Figure 9.
As shown in B1, the value of ITs2 is increased as the fuel injection amount Q is increased (that is, the value is advanced). This is because even if the injection amount Q increases, the injection timing must be advanced as the injection amount Q increases in order to make the injection end timing the same.

Although the injection timing is handled in mm for control purposes, the value multiplied by 0.244 [° / mm] is the crank angle before compression top dead center. Therefore, the larger the value, the more the value is on the advance side.

In step 3, the cooling water temperature Tw and the rotation speed Ne
From this, refer to the map to find the water temperature correction amount for the injection timing,
This is put in the variable ITTw [mm]. In step 4, the value of ITTw and the value of ITs2 are added to obtain the variable I
By advancing to Ts1 [mm], the injection timing is advanced and corrected.

The map contents of ITTw are as shown in B2 of FIG. 9, and the maximum value of ITTw is at idle. The maximum value of ITTw at idle speed is that the combustion temperature is low at the time of idle when the injection amount is small and white smoke is likely to occur, so the fuel is burned well by correcting the advance angle greatly. Is. Further, the lower Tw is, the larger the value of ITTw is, so that it takes time to burn the fuel at a low temperature and the amount of white smoke increases accordingly.

In step 5, the acceleration flag is checked, and when it is not set, it is determined that the acceleration is not in progress, and the process proceeds to step 6 to enter the value of ITs1 into the variable ITso [mm]. ITso is a command injection timing (that is, a control target value of the injection timing). The setting and resetting of the acceleration flag will be described later with reference to FIG.

On the other hand, when the acceleration flag is set, it is determined that the vehicle is accelerating, and the process proceeds to steps 7, 8 and 9.

In step 7, the accelerator opening degree ACC is read, and in step 8, the accelerator opening degree change amount TACC per unit time is TACC = (ACC-ACC- ₁ ) / predetermined time (1) where ACC- ₁ : A correction amount corresponding to the control delay of the injection timing is calculated from the accelerator opening change amount TACC and the rotation speed Ne by referring to the map in step 9, and is calculated by the variable Δ.
Put in IT [mm]. In step 10, the value obtained by adding the value of ΔIT to the value of ITs1 is put in the variable ITso [mm]. During acceleration, the advance angle is corrected by adding only ΔIT to the control target value (ITs1) of the injection timing in the steady state.

The map content of the correction amount ΔIT is as shown in B5 of FIG. 9, and the value of ΔIT is increased as the accelerator opening change amount TACC becomes lower at a constant condition. This is because the lower the rotation speed, the more difficult it is for the timer piston 26 to move to the advance side, and therefore the control target value needs to be greatly shifted to the advance side.

Further, the value of ΔIT is increased as the accelerator opening change amount TACC increases under the condition of the same rotational speed. This is because the fuel injection amount Q increases as the degree of acceleration increases.
Therefore, if the injection timing is not advanced accordingly, the injection will not end at the target injection end time.

At step 11, AC is used for the next control.
The value of C is transferred to the variable ACC _-1 , and in step 12, feedback control of the injection timing is performed so that the actual injection timing matches the command injection timing. This feedback control will be described later in FIG.

FIG. 12 is a flow chart for determining whether to set the acceleration flag, which is executed in synchronization with the Ref signal.

In step 21, the accelerator opening ACC, the fuel injection amount Q, and the rotational speed Ne are read, in step 22, the accelerator opening change amount TACC is calculated by the above equation (1), and in step 23, the fuel injection per unit time is injected. The change amount TQ of the amount is calculated as follows: TQ = (Q−Q ₋₁ ) / predetermined time (2) where Q _{−1 is} the formula of the previous Q ₁ .

At step 24, the accelerator opening change amount TA
CC and threshold value ACCs, and fuel injection amount change amount TQ
And threshold value Qs are respectively compared, and TACC ≧ ACCs
When TQ ≧ Qs, it is determined that the vehicle is accelerating, and the routine proceeds to step 25, where if it is not stationary last time, the acceleration flag (reset state at the time of starting) is set at step 26. In addition,
In step 24, it is judged that the vehicle is accelerating when both TACC ≧ ACCs and TQ ≧ Qs are satisfied, but TACC ≧ AC
It may be configured such that it is determined that the vehicle is accelerating when only one of Cs and TQ ≧ Qs is satisfied.

[0069] Even if this time it is determined that the time of acceleration, when it is determined that the last time a stationary at step 25, the speed change amount TNe per unit time in step 27, TNe = (Ne-Ne - ₁ ) / predetermined time (3) However, Ne ₋₁ : Calculated by the previous expression of Ne, and this rotation speed change amount TNe and threshold value Ne
s is compared in step 28. If TNe ≧ Nes, it is determined that there is a rotation increase due to acceleration, and step 26
To set the acceleration flag.

When TNe <Ne, it is judged that there is no rotation increase and the routine proceeds to step 29, where the acceleration flag is reset. Even if the accelerator opening change amount TACC is large, if there is no increase in rotation, it is determined that the accelerator pedal has been depressed for a moment, and the acceleration flag is not set.
Even in this case, when the correction amount ΔIT is added to ITs1, the advance speed becomes unnecessarily high and rather NO.
This is because the x emission amount will be increased.

During the acceleration, TACC <ACCs or T
When Q <Qs, the routine proceeds to step 29, where the acceleration flag is reset. Step 30 is post-processing.

Since TACC <0 and TQ <0 during deceleration, by setting ACCs and Qs to positive values, the acceleration flag will not be set during deceleration.

FIG. 13 is a flow chart of the feedback control of the injection timing.
Execute in a cycle.

In step 41, the command injection timing (ITs
The basic value of the TCV duty value is obtained from o) and the rotation speed Ne by referring to the map having the content shown in FIG. 14, and this is put in the variable DTY [%]. The value of DTY is set smaller on the retard side as shown in FIG. This is because the smaller the TCV duty value is, the timing control valve 3
3 is opened to increase the amount of leakage from the high pressure chamber 28 to the low pressure side, and the position of the timer piston 26 is moved to the retard side. Further, since the injection timing needs to be advanced as the rotation speed becomes lower, the rotation speed Ne is also used as a parameter in FIG.

At step 42, the timer piston position C
tp [V] is read, and step 4 is performed from this Ctp value.
In step 3, the actual injection timing is obtained by referring to the table having the contents of FIG. 15, and this is put in the variable ITi [mm].

At step 44, the difference ITh [mm] between the actual injection timing and the command injection timing is obtained by the formula ITh = ITi-ITso (4), and from this difference DIT at step 45 a table having the contents of FIG. 16 is obtained. The feedback correction amount is obtained by referring to this value and put in the variable DDTY [mm].

At step 46, the value obtained by adding the value of DDTY to the value of DDTY is put into the variable DTY _SET representing the command TCV duty value, and at step 47, this is transferred to the output register. O from the value of this variable DTY _SET
N and OFF pulses are generated and output to the timing control valve 33.

Considering the control speed of the injection timing further from the mechanical aspect of the injection pump, the advance angle speed increases as the pump internal pressure increases, and the pump internal pressure is referred to as a regulating valve spring (hereinafter referred to as R / V spring). ) Is determined by the set load and the engine speed, it is possible to increase the advance speed by increasing the set load of the R / V spring.

However, if the set weight of the R / V spring is constantly increased, the injection timing cannot be retarded at the time of low load or deceleration, and the PM emission amount and NO
x The amount of emissions will worsen. When the pump internal pressure is set high, the pressure in the timer high pressure chamber 28 cannot be released to the low pressure side, and the high pressure chamber pressure is set to the timer spring 31.
This is because it overcomes the above condition and moves to the low-pressure chamber 30 side (that is, the advance side).

Therefore, in this example, the set load of the R / V spring is switchable so that the set load can be maintained at the same set load as in the conventional case in the steady state, while the difference between the actual injection timing and the command injection timing during acceleration is predetermined. Only when the value is larger than the value, switch to the side where the set load becomes larger for the specified time.

For example, as shown in FIG. 17, since the set load of the R / V spring 61B of the regulating valve 61 is determined by the position of the spring retainer 61C, the vertically movable spring retainer 61C is regulated in FIG. Moving part 6 of valve drive solenoid (hereinafter R / V solenoid) 62
Fixed to 2A, coil 62B of R / V solenoid 62
Are connected to a battery 64 via a power transistor (switching means) 63. In this case, the ECU
When the power transistor 63 is turned on by the ON signal from 35 and the current from the battery 64 is applied to the R / V solenoid 62, the movable portion 62A extends downward in the figure, and the spring retainer 61C position moves downward. Yes (set load increases). During operation of the engine, the valve body 61A of the regulating valve 61 stays at a position where the discharge pressure of the feed pump 3 and the force of the R / V spring 61B balance each other, so that the R / V spring 61B
The pump internal pressure can be obtained according to the set load, and the pump internal pressure rises as the set load increases.

On the other hand, when the power transistor 63 is in the non-energized state, the movable portion 62A moves to the return spring 62.
The action of C retracts upward, and the position of the spring retainer 61C of the regulating valve 61 moves upward (the set load decreases).

FIG. 18 is a flow chart for explaining energization control of the R / V solenoid 62, which is executed in synchronization with the Ref signal.

In step 51, the acceleration flag is checked, and if it is set, it is determined that the vehicle is accelerating, and the process proceeds to step 52.
Difference between actual injection timing and command injection timing ITh (= ITso-I
Ti) is compared with a threshold value (constant value) ITss [mm]. When ITh ≧ ITss, it is determined that the control of the injection timing to the advance side is significantly delayed, and the routine proceeds to step 53.

In step 53, the prescribed time Tts is obtained from the engine speed Ne by referring to the table having the contents shown in FIG. The prescribed time Tts is R as shown in FIG.
/ V solenoid 62 is a value that determines the energization time (that is, the period during which the set load of the R / V spring 61B is increased), and energization during the specified time Tts is Tts.
This is because the pump internal pressure will not rise unless the set load is continuously increased during this period. In FIG. 19, the value of Tts is increased as the engine speed Ne decreases. This is because the lower the rotation speed, the more difficult the pump internal pressure rises.

At step 54, the specified time Tts and R
/ V timer 62 for measuring the energization time of solenoid 62
Compare tm. If the process proceeds to step 54 for the first time, Ttm ≦ Tts, and the process proceeds to step 55 and R / V
Check whether the solenoid 62 is energized. If the routine proceeds to step 55 for the first time, it is in the non-energized state, so in step 56 a timer for measuring the energization time of the R / V solenoid 62 is started, and in step 57 R
Energize the / V solenoid 62.

From the next time, as long as ITh ≧ ITss, step 57 is performed until Ttm reaches the specified time Tts.
At the Tt, continue energizing the R / V solenoid 62
At the timing of m> Tts, the routine proceeds to steps 58 and 59, the timer is reset, and the R / V solenoid 62 is returned to the non-energized state.

The operation of this example will now be described.

In this example, at the time of acceleration in which a control delay of the injection timing occurs, EGR is cut and the injection timing is corrected to the advance side by the correction amount ΔIT corresponding to the control delay of the injection timing. Since the angular speed is increased, the characteristics of the actual injection timing and the EGR rate follow the region where the PM emission amount is small as shown in FIG. 8 (see an arrow different from the black arrow). In the conventional example, the PM emission amount is 2 g / h starting from 22 g / h as shown by the black arrow in FIG.
Although there was no choice but to gradually decrease to PM, in this example, the PM emission amount was increased from 22 g / h to 5 g by increasing the advance speed.
The amount of PM emission at the time of acceleration is effectively suppressed because the amount of PM / h is shifted to a small region at once.

Further, even if the degree of acceleration is the same, the lower the rotation speed, the more difficult the timer piston 26 moves toward the advance side, and the advance speed becomes slower. In contrast, in this example,
Even with the same accelerator opening change amount TACC, the value of ΔIT is increased as the rotation speed becomes lower, so that the advance speed is not slowed down even during acceleration from the low rotation speed region. Further, when the injection amount Q is large in the steady state, the basic injection timing ITs2 is advanced so that the injection ends at the target injection end timing, so this is especially true during acceleration when the injection amount shifts to a region where the injection amount increases. , If the injection timing is not early,
It becomes impossible to finish the injection at the target injection end timing.
On the other hand, in this example, the accelerator opening change amount TACC
Since the value of ΔIT is increased with increasing, the target injection timing in consideration of the control delay of the injection timing can be given even during sudden acceleration (that is, the injection can be performed at the target injection timing).

On the other hand, as shown in FIG. 21, at the time of acceleration such that the vehicle is started to accelerate and reaches a predetermined steady running load (for example, 50 km / h road load load), the rotation drop that occurs during a gear change during acceleration is suppressed. As a result, the actual injection timing ITi is largely deviated from the command injection timing ITso at the time of switching from the idle speed to the first speed and at the time of switching from the first speed to the second speed. Since this is a characteristic that the pump internal pressure rises in proportion to the number of revolutions, the lower the rotation speed, the larger the delay in the rise of the pump internal pressure due to the fall of the rotation, and the delay of the actual injection timing from the command injection timing becomes noticeable. Because.

On the other hand, in this example, the actual injection timing I
The difference ITh between Ti and the command injection timing ITso is the predetermined value ITs.
When it is considered to be larger than s, the set load of the R / V spring 61B is switched to a larger side by energization of the R / V solenoid 62, and the pump internal pressure is increased from that before acceleration. As a result, the advance speed does not slow down even during gear changes, especially in the low speed range.

In FIG. 21, the R / V solenoid 6
The energization section of 2 differs between when switching from idle to 1st speed and when switching from 1st speed to 2nd speed.
It is shorter when switching to high speed. This is because the rotation speed at the time of switching to the 2nd speed is higher than that at the time of switching to the 1st speed, so the pump internal pressure is accordingly high, and the actual injection timing ITi easily catches up with the command injection timing ITso (the R / V solenoid 62 is It becomes de-energized soon).

Further, since the energization time to the R / V solenoid 62 (that is, the specified time Tts) is increased as the rotation speed is lower, the pump internal pressure can be increased without excess or deficiency according to the pump internal pressure immediately before acceleration. Although the responsiveness of the injection timing is improved by increasing the pump internal pressure,
As the control system is likely to diverge if left rising, responsiveness and stability as a control system are ensured by not increasing the pump internal pressure unless necessary (that is, increasing the pump internal pressure for a specified time). The sexual balance is improved.

FIG. 22 is a control block diagram of the injection timing of the second embodiment and corresponds to FIG. 9 of the first embodiment.

As can be seen by comparing the two figures, this example only corrects the injection timing during acceleration.
The set load of the / V spring does not change between acceleration and steady operation. In this case, during start-up acceleration to reach a predetermined steady running load, the actual injection timing is significantly delayed from the command injection timing (PM emission amount increases) due to the rotation drop due to the gear change during acceleration. As described above in the first embodiment.

To deal with this, in this example, the value of the correction amount ΔIT is made different from that of the first embodiment, and the value of ΔIT is different from that of the first embodiment under the condition that the accelerator opening change amount TACC and the rotation speed Ne are the same. Set to a large value. An example is shown in FIG. 23. When the accelerator opening change amount TACC is constant, ΔI
The value of T is set to a value approximately twice that of the first embodiment.

As a result, looking at the movement of the actual injection timing ITi under the same acceleration condition as in FIG. 21, as shown in FIG.
In most of the advance angle correction period, the actual injection timing ITi advances from the command injection timing ITso (that is, an excessive advance angle). In other words, the correction amount ΔIT is made excessive in anticipation of the fact that the advance side is greatly delayed due to the influence of the rotation drop due to the gear change during acceleration, and thus the correction amount ΔIT is increased accordingly. Even if the rotation is dropped, the PM emission amount can be reduced (NOx emission amount is slightly increased).

FIG. 25 is a control block diagram of the injection timing of the third embodiment and corresponds to FIG. 9 of the first embodiment.

The control speed of the injection timing changes not only with the pump internal pressure but also with the set load of the timer spring 31, and the advance speed can be increased by reducing the set load of the timer spring 31. However, also in this case, if the set load of the timer spring 31 is always made small, the injection timing cannot be retarded during deceleration, and the PM emission amount and the NOx emission amount are rather deteriorated. This is because when the set load of the timer spring 31 is set small, the timer piston 26 moves to the low pressure chamber 30 side (that is, the advance side).

Therefore, in this example, the timer spring 3
The set load of No. 1 is configured to be switchable, and the set load of the timer spring 31 is switched to the side where the set load of the timer spring 31 is reduced only for a specified time during acceleration and only when the difference between the actual injection timing and the command injection timing is larger than a predetermined value.

For example, as shown in FIG. 26, a timer shim 71 which can be moved up and down in the drawing is provided with a drive solenoid (hereinafter referred to as a timer shim solenoid) 7 for the timer shim.
2 fixed to the movable part 72A, the timer shim solenoid 7
The second coil 72B is connected to the battery 64 via the power transistor 73. In this case, the ECU 35
When the timer shim solenoid 72 is energized by the ON signal from the, the movable portion 72A is pulled downward in the figure against the spring 72C, and the position of the timer shim 71 moves downward (the set load decreases). The reduction of the set load of the timer spring 31 reduces the low pressure chamber 3 of the timer piston 26.
This means that the moving speed (advancing speed) to the 0 side becomes higher.

On the other hand, when the timer shim solenoid 72 is de-energized, the movable portion 72A is pushed upward by the spring 72C, and the position of the timer shim 71 moves upward (the set load increases).

FIG. 27 is a flow chart for controlling the energization of the timer shim solenoid 72, which is shown in FIG. 18 of the first embodiment.
18 except that the specified time Tts2 is different from that in FIG. 18 (steps 61 and 62 in FIG. 27), and Tts2 <Tt.
s. This is because it is better to drive the timer directly than to increase the pump internal pressure, and thus the energization time to the timer shim solenoid 72 can be shortened as compared with the case where the pump internal pressure is increased.

In this example, since the timer is driven directly, the energization time can be made shorter than in the first embodiment when there is a rotation drop due to a gear change during acceleration. However, since a large driving force of, for example, about 7 kg is required to directly drive the timer, the first embodiment is more advantageous in terms of space.

FIG. 28 is a control block diagram of the injection timing of the fourth embodiment and corresponds to FIG. 9 of the first embodiment.

In this example, in addition to the first embodiment, the injection timing is retarded by the correction amount ΔIT corresponding to the control delay of the injection timing during deceleration, and the actual injection timing and the command injection timing are also maintained during deceleration. Only when the difference is larger than a predetermined value, the internal pressure of the pump is switched to the smaller side for a specified time.

In the following, the parts added to the first embodiment will be mainly described. In FIG. 28, B5 is calculated from the accelerator opening change amount TACC and the rotational speed Ne at the time of deceleration.
Calculate the correction amount ΔIT by referring to the map of the contents shown in
At 31, the command injection timing ITso is calculated by the equation ITso = ITs1-ΔIT (5).

ΔIT is a value which is also referred to during acceleration,
By adding a negative sign to ΔIT during deceleration, equation (5) becomes an equation for retard correction during deceleration.

In FIG. 29, a deceleration flag is introduced in addition to the acceleration flag, and step 7 is different from FIG. 12 of the first embodiment.
1, 72, 73, 74 and 75 are different. In step 71, when the conditions of | TACC | ≧ ACCs and | TQ | ≧ Qs are satisfied, deceleration time is included in addition to acceleration time. Is determined to be decelerating, the process proceeds to step 75, and the deceleration flag (initial state is reset state)
Set. In step 72, | TNe | <Ne
When the condition of is satisfied, the case where the accelerator pedal is largely returned for a moment is included. In this case, step 25,
At 73, both the acceleration flag and the deceleration flag are reset.

On the other hand, as shown in FIG. 30, the set load of the R / V spring 61B can be switched in three stages.

In FIG. 30, an R / V solenoid 81 having the same capacity as the R / V solenoid 62 of the first embodiment is provided symmetrically in the vertical direction in FIG.
In the non-energized state of the V solenoids 62 and 81 (see the center of FIG. 31), both movable portions 62A and 81A are pressed by the respective springs 62C and 81C from the opposite directions to be in contact with each other (neutral state).

When only the other R / V solenoid 62 is energized from this neutral state, the movable portion 6 is moved by the electromagnetic force.
2A is pushed downward in the figure against the spring 62C, and the position of the spring retainer 61C moves downward, and R /
The set load of the V spring 61B increases (see the left side of FIG. 31). The movable portion 81A of the other R / V solenoid 81 is pushed by the spring 81C and moves downward while being in contact with the movable portion 62A.

On the other hand, the other R / V solenoid 8
When only one is energized, the movable part 81A is pushed upward by the electromagnetic force. At this time, another R /
Since the movable portion 62A of the V solenoid 62 is pushed by the spring 62C and moves upward while being in contact with the movable portion 81A, the position of the spring retainer 61C moves upward (see the right side of FIG. 31), and the R / V spring 61B moves. Set load is reduced.

As shown in FIG. 32, the two R / V solenoids 62, 81 thus constructed are in a non-energized state when the two R / V solenoids 62, 81 are in the steady state, and the actual injection timing ITi is in acceleration. And command injection timing ITs
When the difference ITh of o is greater than or equal to a predetermined value ITss, the R / V solenoid 62 is energized, the other R / V solenoid 81 is deenergized, and the actual injection timing ITi and the command injection timing ITs are being decelerated.
The ECU 35 controls so that the R / V solenoid 81 is in the energized state and the R / V solenoid 62 is in the non-energized state when the difference ITh of o is greater than or equal to the predetermined value ITss. Since FIG. 32 takes into consideration deceleration, it is different from FIG. 18 of the first embodiment in step 8.
1, 82, 83, 84, 85, 86 are different.

In this example, at the time of deceleration in which a control delay of the injection timing occurs, by retarding the injection timing by the correction amount ΔIT corresponding to the control delay, the retarding speed during deceleration increases. Both the PM emission amount and the NOx emission amount during deceleration due to the control delay can be prevented from deteriorating.

Further, when there is a temporary increase in rotation due to gear change during deceleration, such as when performing deceleration operation to an idle state, especially when switching from 2nd speed to 1st speed or from 1st speed to idle The actual injection timing ITi is greatly delayed from the command injection timing ITso at the time of switching to the
Emissions both worsen.

On the other hand, in this example, the actual injection timing IT
When i is delayed from the command injection timing ITso by a predetermined value ITss or more, the pump internal pressure is made lower than in the steady state, so that the retarding speed of the injection timing is slowed even if there is a temporary increase in rotation due to gear change during deceleration. Never. This prevents the actual injection timing from being significantly delayed from the command injection timing during deceleration accompanied by gear change.

Needless to say, an embodiment in which only the injection timing is retarded during deceleration can be considered in correspondence with the second embodiment.

FIG. 33 is a control block diagram of the injection timing of the fifth embodiment and corresponds to FIG. 25 of the third embodiment.

In this example, in addition to the third embodiment, at the time of deceleration in which the control delay of the injection timing occurs, the injection timing is corrected by the correction amount ΔIT corresponding to the control delay, and even during deceleration Only when the difference between the injection timing and the command injection timing is larger than a predetermined value, the timer spring load is switched to the larger side for a specified time.

Specifically, in B41 of FIG. 33, the command injection timing ITso during deceleration is ITso = ITs1−ΔIT × Kg (6) where ΔIT: correction amount Kg: deceleration correction coefficient (a positive value less than 1) ) The injection timing is corrected by retarding the injection timing.

Here, by setting Kg <1, if the accelerator opening change amount TACC and the rotation speed Ne are the same,
The correction amount is smaller than that in the fourth embodiment. This is shown in Figure 2.
6, when the timer piston 26 is moved to the advance side, the force of the timer spring 31 acts in the direction opposite to the advance direction to slow down the advance speed, while the timer piston 26 is moved to the retard side. This is because when moving, the force of the timer spring 31 acts in the retard direction to increase the retard speed, so that the correction amount may be smaller than that when advancing.

On the other hand, as shown in FIG. 34, the set load of the timer spring 31 can be switched in three steps. In FIG. 34, only the two timer shim solenoids 71 and 91 are shown.

Two timer shim solenoids 72, 91
The movement of the two R / V solenoids 6 shown in FIG.
It is similar to the movement of 2,81. A timer shim solenoid 91 having the same capacity as the timer shim solenoid 72 of the third embodiment is provided symmetrically in the vertical direction in FIG. 34, and the two timer shim solenoids 72 and 91 are in a non-energized state. Is in the neutral state shown in the center of. In this case, when only one of the timer shim solenoids 91 is energized, the position of the timer shim 71 moves downward in FIG. 34 and the set load of the timer spring 71 becomes small (see the left side of FIG. 35), and the other timer When only the shim solenoid 72 is energized, the position of the timer shim 71 moves upward in FIG. 34 and the set load of the timer spring 71 increases (see the right side of FIG. 35).

As shown in FIG. 36, the two timer shim solenoids 72, 91 thus constructed are in a non-energized state when both are stationary, as shown in FIG. When the time difference ITh is greater than or equal to a predetermined value ITss, the timer shim solenoid 9
1 is energized, the timer shim solenoid 72 is de-energized, and when decelerating and the difference ITh between the actual injection timing and the command injection timing is the predetermined value ITss or more, the timer shim solenoid 7
The ECU 35 controls so that 2 is energized and the timer shim solenoid 91 is de-energized. That is, the third
27 of the embodiment, the steps 81, 83, 91, 92, 9
3, 94 are different.

In this example as well, the retard angle speed during deceleration is increased by retarding the injection timing during deceleration when the injection timing control delay occurs, so the PM emission amount during deceleration due to the injection timing control delay is increased. And the NOx emission amount can be prevented from deteriorating, and the actual injection timing ITi is the command injection timing ITs.
Since the set load of the timer spring is made higher than that in the steady state when it is delayed more than the predetermined value ITss from o, even if there is a temporary increase in rotation due to gear change during deceleration,
The retarding speed of the injection timing does not slow down. This prevents the actual injection timing from being significantly delayed from the command injection timing during deceleration accompanied by gear change. Such effects are similar to those of the fourth embodiment.

Furthermore, since the timer is driven directly in the fifth embodiment, the energization time can be made shorter than that in the fourth embodiment.

In the embodiment, the case where the EGR cut is performed at the time of acceleration has been described, but the EGR region may be reduced instead of the EGR cut.

In the embodiment, the electronically controlled distribution type injection pump has been described, but the control of the fuel injection amount remains mechanical, and a so-called partial electronic control pump in which only the injection timing is electronically controlled by the timing control valve is used. Can also be applied.

Finally, regarding the timing control valve 33 of FIG. 4, the leak flow rate from the high pressure chamber 28 increases as the TCV duty value decreases, but conversely, the leakage flow rate from the high pressure chamber 28 increases as the TCV duty value increases. The configuration that increases the leakage flow rate (that is, T
(The CV duty value is the ON time ratio of a fixed cycle)
It can also be applied to the timing control valve of.

[0132]

According to the first aspect of the present invention, a distribution type injection pump in which the flow rate of fuel bypassed from the high pressure chamber at one end of the timer piston and leaked to the low pressure side is adjusted by the drive amount given to the timing control valve, and at least the engine. A means for calculating the basic injection timing according to the number of revolutions, a means for calculating the command injection timing by correcting the basic injection timing to the advance side with a correction amount during acceleration, and a sensor for detecting the timer piston position, Since the means for calculating the actual injection timing from the detection value of the timer piston position sensor and the means for feedback-correcting the drive amount given to the timing control valve so that the actual injection timing matches the commanded injection timing are provided. , Advancement speed is increased at the time of acceleration that causes injection timing control delay, and P
The amount of M emission can be effectively suppressed.

According to a second aspect of the present invention, in the first aspect of the present invention, when it is judged from the load change amount per unit time that acceleration is being performed for the first time and there is no increase in engine rotation from the previous time, the advance angle correction during acceleration is performed. Therefore, the advance speed is not unnecessarily increased when the accelerator pedal is fully depressed for a moment, and the NOx emission amount is prevented from increasing due to the unnecessary increase in the advance speed. You can

In a third aspect based on the first or second aspect, the set load of the return spring of the regulating valve can be switched so that the difference between the actual injection timing and the command injection timing during acceleration is large. Since the set load of the return spring is switched to the side where the set load of the return spring is large when the value is equal to or more than the predetermined value, the advance speed is not slowed down even if the rotation drop occurs during gear change during acceleration.

[0135] In a fourth aspect based on the first or second aspect, the set load of the timer spring is switchable, and at the time of acceleration and when the difference between the actual injection timing and the command injection timing is a predetermined value or more. Since the specified time is switched to the side where the set load of the timer spring becomes smaller at a certain time, the advance speed will not be slowed down even if a rotation drop may occur during gear change during acceleration, and the specified time will be further shortened. be able to.

A fifth aspect of the present invention is a distribution type injection pump in which the flow rate of the fuel bypassed from the high pressure chamber at one end of the timer piston and leaked to the low pressure side is adjusted by the drive amount given to the timing control valve, and at least the engine speed. Means for calculating the basic injection timing according to the above, a means for calculating the command injection timing by correcting the basic injection timing to the retard side by a correction amount during deceleration, a sensor for detecting the timer piston position, and this timer. Since the means for calculating the actual injection timing from the detection value of the piston position sensor and the means for feedback-correcting the drive amount given to the timing control valve so that the actual injection timing matches the commanded injection timing are provided, the injection is performed. The retard angle speed can be increased during deceleration that causes a control delay of the timing, and P It is possible to prevent the deterioration of emissions and NOx emissions together.

According to a sixth aspect of the invention, in the fifth aspect of the invention, when it is determined from the load change amount per unit time that the engine is decelerating for the first time this time and there is no decrease in the engine rotation from the previous time, the retard correction during the deceleration is performed. Since it does not perform, the retard speed is not unnecessarily increased when the accelerator pedal is largely returned for a moment.

In a seventh aspect based on the fifth or sixth aspect, the set load of the return spring of the regulating valve is switchable, and the difference between the actual injection timing and the command injection timing during deceleration is set. When the set value of the return spring is smaller than the predetermined value, the set load of the return spring is switched to the smaller side for the specified time. Therefore, even if there is a temporary increase in rotation due to a gear change during deceleration, the retarding speed does not slow down.

In an eighth aspect based on the fifth or sixth aspect, the set load of the timer spring is configured to be switchable, and at the time of deceleration and when the difference between the actual injection timing and the command injection timing is a predetermined value or more. Since the specified time is switched to the side where the set load of the timer spring becomes large at a certain time, even if there is a temporary increase in rotation due to gear change during deceleration, the retarding speed does not slow down and the specified time is further shortened. be able to.

In a ninth aspect based on any one of the first to eighth aspects, the correction amount has a larger value as the engine speed becomes lower, and therefore, when accelerating from a low speed range, It does not slow down the advance speed and does not slow down the retard speed even during deceleration in the low speed range.

In a tenth aspect of the invention, in any one of the first to eighth aspects of the invention, the larger the load change amount per unit time is, the larger the correction amount is. It is possible to give the target injection timing in consideration of the control delay of the injection timing even during sudden deceleration.

In an eleventh aspect of the invention, in the third or seventh aspect of the invention, the specified time is a value that increases as the engine speed decreases, so that the pump internal pressure can be adjusted in accordance with the pump internal pressure immediately before acceleration. It is possible to raise the pump internal pressure and reduce the pump internal pressure without excess or deficiency according to the pump internal pressure immediately before deceleration.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of an electronically controlled distributed fuel injection pump.

FIG. 2 is a perspective view of a rotary solenoid.

FIG. 3 is a diagram showing a positional relationship between a rotary shaft of a rotary solenoid and a control sleeve.

FIG. 4 is a sectional view of a timer portion.

FIG. 5 is a control system diagram of an electronically controlled injection pump.

FIG. 6 EG for a vehicle with a 2WD and a manual transmission
It is a system diagram of an R control device.

FIG. 7 is a table showing the control contents in the EGR control device of FIG.

FIG. 8 is a characteristic diagram of PM emission amount with respect to injection timing / EGR during acceleration.

FIG. 9 is a block diagram showing an outline of injection timing control of the first embodiment.

FIG. 10 is a flowchart showing a main routine of injection timing control.

FIG. 11 is a characteristic diagram of a fuel injection amount Q.

FIG. 12 is a flow chart for explaining setting of an acceleration flag.

FIG. 13 is a flowchart for explaining feedback control of injection timing.

FIG. 14 is a characteristic diagram of a basic value DTY of a TCV duty value.

FIG. 15 is a characteristic diagram of the actual injection timing ITi with respect to the timer piston position Ctp.

FIG. 16 is a characteristic diagram of a feedback correction amount DDTY.

FIG. 17 is a sectional view of a regulating valve 61 and an R / V solenoid 62.

FIG. 18 is a flowchart for explaining energization control for the R / V solenoid 62.

FIG. 19 is a characteristic diagram of a specified time Tts.

FIG. 20 is a waveform diagram showing a rise in pump internal pressure during acceleration.

FIG. 21 is a waveform diagram for explaining the action at the time of acceleration accompanied by gear change.

FIG. 22 is a control block diagram of the injection timing of the second embodiment.

FIG. 23 is a characteristic diagram of the correction amount ΔIT according to the second embodiment.

FIG. 24 is a waveform diagram for explaining an operation at the time of acceleration accompanied by a gear change according to the second embodiment.

FIG. 25 is a control block diagram of the third embodiment.

FIG. 26 is a sectional view of a timer shim solenoid 72 of the third embodiment.

FIG. 27 is a flowchart for explaining energization control of the timer shim solenoid 72 of the third embodiment.

FIG. 28 is a control block diagram according to the fourth embodiment.

FIG. 29 is a flow chart for explaining setting and resetting of an acceleration flag and a deceleration flag according to the fourth embodiment.

FIG. 30 shows two R / V solenoids 62 of the fourth embodiment,
81 is a sectional view of 81. FIG.

FIG. 31 shows two R / V solenoids 62 of the fourth embodiment,
It is a figure which shows operation | movement of 81.

FIG. 32 shows two R / V solenoids 62 of the fourth embodiment,
It is a flow chart for explaining energization control to 81.

FIG. 33 is a control block diagram of the fifth embodiment.

FIG. 34 is a sectional view of two timer shim solenoids 72, 91 of the fifth embodiment.

FIG. 35 is a view showing the operation of the two timer shim solenoids 72, 91 of the fifth embodiment.

FIG. 36 is a flowchart for explaining energization control of two solenoids 72, 91 of the fifth embodiment.

FIG. 37 is a diagram corresponding to the claim of the first invention.

FIG. 38 is a diagram corresponding to the claim of the fifth invention.

[Explanation of symbols]

 16 Control Sleeve 26 Timer Piston 31 Timer Spring 33 Timing Control Valve 35 ECU 36 Accelerator Sensor 39 Timer Piston Position Sensor 61 Regulator Valve 62 R / V Solenoid 71 Timer Shim 72 Timer Shim Solenoid 81 R / V Solenoid 91 Timer Sim Solenoid 101 Timing Control valve 102 Basic injection timing calculation means 104 Commanded injection timing calculation means 105 Timer piston position sensor 106 Actual injection timing calculation means 107 Injection timing feedback correction means 111 Commanded injection timing calculation means

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display area F02D 45/00 F

Claims (11)

[Claims] Claim: What is claimed is: 1. A distribution type injection pump in which a fuel flow rate of fuel bypassed from a high pressure chamber at one end of a timer piston and leaked to a low pressure side is adjusted by a drive amount given to a timing control valve, and a basic type according to at least an engine speed. Means for calculating the injection timing, means for calculating the command injection timing by correcting the basic injection timing to the advance side by the correction amount at the time of acceleration, a sensor for detecting the timer piston position, and a timer piston position sensor A diesel engine comprising means for calculating the actual injection timing from the detected value and means for feedback-correcting the drive amount given to the timing control valve so that the actual injection timing matches the commanded injection timing. Fuel injection pump controller. 2. The advance angle correction at the time of acceleration is not performed when it is determined that acceleration is being performed for the first time this time based on the load change amount per unit time and there is no increase in engine rotation from the previous time. 1. A control device for a fuel injection pump of a diesel engine according to 1. 3. The set load of the return spring of the regulating valve is configured to be switchable, and the set load of the return spring is set during acceleration and when the difference between the actual injection timing and the command injection timing is a predetermined value or more. The control device for a fuel injection pump of a diesel engine according to claim 1 or 2, wherein the control is switched to a larger side for a specified time. 4. The set load of the timer spring is configured to be switchable, and when the difference between the actual injection timing and the command injection timing is at least a predetermined value during acceleration, the set load of the timer spring is reduced. The control device for a fuel injection pump of a diesel engine according to claim 1 or 2, wherein switching is performed for a specified time. 5. A distribution type injection pump in which the flow rate of fuel that is bypassed from the high pressure chamber at one end of the timer piston and leaked to the low pressure side is adjusted by the drive amount given to the timing control valve, and at least a basic type in accordance with the engine speed. Means for calculating the injection timing, means for calculating the command injection timing by correcting the basic injection timing to the retard side by the correction amount at the time of deceleration, a sensor for detecting the timer piston position, and a timer piston position sensor A diesel engine comprising means for calculating the actual injection timing from the detected value and means for feedback-correcting the drive amount given to the timing control valve so that the actual injection timing matches the commanded injection timing. Fuel injection pump controller. 6. The retardation correction at the time of deceleration is not performed when it is judged from the load change amount per unit time that the engine is decelerating for the first time this time and there is no decrease in engine rotation from the previous time. 5. A control device for a fuel injection pump of a diesel engine according to 5. 7. The set load of the return spring of the regulating valve is configured to be switchable, and the set load of the return spring is set when decelerating and when the difference between the actual injection timing and the command injection timing is a predetermined value or more. The control device for a fuel injection pump of a diesel engine according to claim 5 or 6, wherein the control is switched to a smaller side for a specified time. 8. The set load of the timer spring is configured to be switchable, and the set load of the timer spring is increased when decelerating and when a difference between the actual injection timing and the command injection timing is a predetermined value or more. The control device for a fuel injection pump of a diesel engine according to claim 5 or 6, wherein the control is performed for a predetermined time. 9. The control device for a fuel injection pump of a diesel engine according to claim 1, wherein the correction amount has a larger value as the engine speed becomes lower. 10. The larger value of the load change amount per unit time of the correction amount is the larger value.
A control device for a fuel injection pump of a diesel engine according to any one of 1 to 8. 11. The control device for a fuel injection pump of a diesel engine according to claim 3, wherein the specified time is a value that increases as the engine speed decreases.