JPS6059417B2 - fuel injector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fuel injection device, and will be described in more detail.The present invention relates to a fuel injection device, and will be described in more detail. The present invention relates to a fuel injection device that can ensure a smooth change in engine rotational speed under different conditions.

Conventional engine speed control during idle in a fuel injection system is proposed in Japanese Patent Application Laid-Open No. 47-35525, in which a governor characteristic for idle is preset for idle in the governor device, and When the position of the idle accelerator reaches a predetermined idle accelerator position, the idle speed is controlled according to the idle governor characteristics.

Therefore, in this case, the accelerator position in the idle state is constant, and due to changes in external environmental conditions, the desired idle rotation speed cannot be obtained even if the accelerator position is at the predetermined idle position. It was hot. In order to eliminate this drawback and ensure that the idle speed is maintained exactly at the desired value, the speed information is fed back and the position of the fuel adjustment member is adjusted according to the speed only in the idle state. A control method has been considered (Japanese Utility Model Application Publication No. 15121/1983). However, if a control operation different from the conventional governor operation is performed only in the idle state, if the accelerator is pressed when moving from the idle state to the running state, the rotation speed will decrease. This was extremely unsatisfactory. Therefore, an object of the present invention is to perform a regulating operation so that the idle speed can be maintained at a predetermined value and the engine speed can smoothly increase when transitioning from an idle state to a running state. The objective is to provide a fuel injection device that can perform The configuration of the present invention is to provide a control system that controls the position of the fuel injection amount adjusting member based on an electric signal without indicating the operating conditions of the internal combustion engine to obtain desired governor characteristics in the electronically controlled fuel injection device. a first calculating means for calculating a target idle speed corresponding to the current operating conditions of the internal combustion engine; a first means for detecting a difference between the target idle speed and the actual speed; a second calculation means for generating a virtual accelerator signal for setting the rotation speed to the target idle rotation speed based on the detection result in the means; and a second means for outputting an accelerator signal according to the actual accelerator pedal operation amount; switch means for selectively applying either the accelerator signal or the virtual accelerator pedal signal to the control system as accelerator position information; and a switch means for detecting whether or not the internal combustion engine is in a desired idle operating state. When it is determined that the vehicle is in an idling state, the virtual accelerator pedal signal is selectively output, and when it is determined that the vehicle is not in an idling state, the accelerator signal is selectively output. It is characterized in that it is equipped with a control means. Hereinafter, the present invention will be explained in detail with reference to illustrated embodiments. FIG. 1 shows, in cross section, a mechanical portion of an embodiment of a fuel injection device according to the present invention.

In this embodiment, a distribution type fuel injection device for four cylinders is taken as an example of the fuel injection device, and this fuel injection device 1
is used in combination with a vehicle internal combustion engine (not shown),
Together with a control device 31 (see FIG. 4), which will be described later, it constitutes an electronically controlled fuel injection device. The fuel injection device 1 includes a vane pump 4 driven by a drive shaft 3 bearing a housing 2, and the drive shaft 3 is driven to rotate at a rotation speed related to the rotation speed of an internal combustion engine (not shown). By this,
A vane pump 4 supplies fuel under pressure into the housing chamber 6 . A cam disc 8 is connected to one end of the drive shaft 3 via a driving disc 7.
A plunger 9 is pressed against one side by a plunger spring (not shown), and when the drive shaft 3 rotates, the plunger 9 rotates and reciprocates. One end of the plunger 9 is provided with intake slits 10 and 11 (only two of the four intake slits are shown in the drawing), the number of which corresponds to the number of cylinders in the engine. Intake boat 12 during the downward stroke of
When the intake slit and the intake slit overlap, pressurized fuel flows into the high pressure chamber 13 and the passage 1 in the plunger 9.
4 and inhaled. This inhaled pressurized fuel begins to be compressed when the intake boat is closed by the rotary lift action of the plunger. When the plunger 9 continues its rotational lift and the distributor slit 15 communicating with the passage 14 overlaps with the outlet passage (not shown), the compressed high-pressure fuel pushes up the delivery valve (not shown) and flows into the injection nozzle. is injected into the engine's fuel chamber. When the plunger 9 is further pushed up by the cam tooth 8, the cut-off boat 16 communicating with the passage 14 is disengaged from the control sleeve 17, thereby ending fuel injection. By controlling the relative position between the control sleeve 17 and the plunger 9, the end timing of fuel injection can be controlled.
In other words, an electromagnetic actuator 18 is connected to the control sleeve 17 in order to control the injection amount.
An electromagnetic actuator 18 is shown in FIGS. 2 and 3.

The electromagnetic actuator 18 has a field core 20 around which an excitation coil 19 is wound, and a rotor 21 to which a field flux is applied by the field core 20. Rotor 21 is spring 2
2 and 23 in the direction of arrow A, and when the excitation coil 19 is excited, the rotor 21 rotates in the opposite direction against the spring bias, and the angle at which the spring force and the electromagnetic force are balanced is Stop at the position. Therefore, by controlling the value of the current flowing through the excitation coil 19, the shaft 24 of the rotor 21 rotates, and the position of the control sleeve 17 connected to the lower end of the shaft 24 (see FIG. 1) is controlled. The electromagnetic actuator 18 is provided with a position sensor 25 for detecting the rotational angular position of the rotor 21, as shown in FIG.

The position sensor 25 has a detection coil 27 and an auxiliary coil 28 wound around an iron core 26 having two magnetic paths as shown. A movable detector 29 made of a magnetic material fixed to the shaft 24 rotates as the shaft 24 rotates.
The inductance of the detection coil 27 is made to correspond to the rotational position of the shaft 24. Fixed detector 30
is an adjustment member that is not linked to the rotation of the shaft 24, and is used to adjust the inductance of the auxiliary coil 28. Figure 4 shows a system that obtains the required governor characteristics, maintains the engine speed at a predetermined value in the idling state, and prevents a temporary drop in the engine speed even when the vehicle moves from the idling state to the running state. So that I don't invite you,
A block diagram of a control device that drives and controls the electromagnetic actuator 18 is shown.

This control device 31 has a control sleeve position calculation circuit 32 for calculating a control sleeve position for obtaining optimal governor characteristics according to engine operating conditions. The control sleeve position calculation circuit 32 includes:
A rotation signal Sl indicating the engine rotation speed output from the rotation sensor 33, a water temperature signal S2 indicating the temperature of the engine cooling water, a fuel temperature signal S3 indicating the fuel temperature, an atmospheric pressure signal S4 indicating the atmospheric pressure, and a boost pressure. A boost pressure signal S5 indicating the engine speed is applied from a sensor (not shown), and a flow rate signal S6 from an air flow sensor (not shown) is input as a signal indicating the operating condition of the engine. The control sleeve position calculation circuit 32 is further supplied with an accelerator signal S7 outputted from the accelerator pedal position detection circuit 34 and indicating the actual accelerator pedal operation amount via a changeover switch 35. outputs a target position signal S8 indicating the optimum control sleeve position at any given time based on each of these input signals. The target position signal S8 is a detection signal S output from the position sensor 25 and indicating the actual control sleeve position.
9 is applied to the other input of the error amplification circuit 36, which is applied to one input, and outputs the target position signal S8 and the detection signal S9.
An error signal SlO corresponding to the difference between the two is output from the error amplification circuit 36. The error signal SlO is input to a drive circuit 50 (for example, a pulse width modulator), and its output is applied to the excitation coil 19 of the electromagnetic actuator 18 as a drive control signal S2O for the electromagnetic actuator 18. The electromagnetic actuator 18 is driven so that the level of the error signal SlO becomes zero. In this way, a control system is constructed that controls the position of the fuel injection amount adjusting member based on the electrical signal indicating the operating conditions of the internal combustion engine to obtain the required governor characteristics. The position 17 is determined by the target position signal S8. Using this above-mentioned control system, in order to maintain the idle rotation speed at a predetermined value during idle, the water temperature signal S2,
A signal Sll indicating the on/off state of the air conditioner and a battery signal Sl2 indicating the voltage level of the battery are input, and based on these input signals, the optimum target idle rotation that matches the engine operating conditions at the time is determined. A target idle rotation speed calculation circuit 37 is provided to calculate the number.

The target signal S, 3 indicating the target idle rotation speed calculated in the target idle rotation speed calculation circuit 37 is sent together with the rotation signal S1 to an error amplification circuit 38 for detecting the difference between the target idle rotation speed and the actual rotation speed. An error signal Sl4 having a magnitude corresponding to the difference between the two signals Sl and Sl3 is output. Actual rotation speed N and target idle rotation speed N.
An error signal Sl, indicating the difference between the target idle rotation speed N and the target idle rotation speed N, is input to the virtual accelerator pedal position calculation circuit 39, and is input to the virtual accelerator pedal position calculation circuit 39. A virtual accelerator pedal signal Sl5 indicating a virtual accelerator pedal position such that the engine is operated at is output. Virtual accelerator pedal signal Sl5
is input to the changeover switch 35, and the changeover switch 3
5, either the accelerator signal S7 or the virtual accelerator pedal signal Sl5 is selectively input to the control sleeve position calculation circuit 32 as accelerator position information. In order to control the switching of the changeover switch 35, the control device 31 includes a changeover control circuit 41 including an accelerator switch 40.
It is equipped with The switching control circuit 41 controls the rotation speed N and the target idle rotation speed N. The rotation signal S is used to determine the size of the
1 and a first comparator 42 to which the target signal Sl3 is input;
A second comparator 4 receives the accelerator signal S7 and the virtual accelerator pedal signal Sl5 in order to determine the magnitude of the actual accelerator pedal position and the virtual accelerator pedal position calculated by the virtual accelerator pedal position calculation circuit 39.
3. The output of the first comparator 42 is N>NO
In the case of RO. ．． , and RlJ occurs when N≦NO. The accelerator switch 40 outputs a detection signal Sl6 that becomes 71 when the accelerator is released, thereby making it possible to detect whether or not the vehicle is in an idling state. The output of the first comparator 42 and the detection signal Sl6 are input to an AND circuit 44, and the output of the AND circuit 44 is input to the output of the R-S flip-flop 45. It is input to the input terminal S. Therefore, the accelerator switch 40 detects that the engine is in an idling state, and the rotational speed N is N. When the output of the AND circuit 44 sets the R-S flip-flop 45, the level of the Q output. The changeover switch 35 is switched as shown by the solid line, and the virtual accelerator pedal signal Sl5 is sent to the control sleeve position calculation circuit 32.
is input. As a result, the control device 31 controls the number of revolutions of the engine to be N during idling operation. Fuel so that
The injection amount can be controlled. Switching of the changeover switch 35 to the accelerator pedal position detection circuit 34 side is performed by setting the Q output to RO by the reset operation of the R-S flip-flop 45 based on the output of the second comparator 43.

That is, if the accelerator pedal is depressed while the selector switch 35 is switched as shown by the solid line, the level of the detection signal S, 6 becomes ROJ, and the set input terminal of the R-S flip-flop 45 becomes S becomes ROJ. In this state, when S7≧Sl5, the output of the second comparator 43 changes from ROJ to RlJ, and the Q output changes to Rl.
OJ is activated, the changeover switch 35 is switched as shown by the dotted line in the figure, the accelerator signal S7 is input to the control sleeve position calculation circuit 32, and the control sleeve position is controlled in accordance with the actual accelerator operation.
According to this configuration, except during idling operation. So,
The accelerator signal S7 is input to the control sleeve position calculation circuit 32, and partial load or full load operation is performed according to predetermined governor characteristics.

The release state of the accelerator, that is, the idle state is detected by the accelerator switch 40, and the actual engine rotation speed is the target idle rotation speed N. When it becomes smaller, the R-S flip-flop 45 is set, and its Q output becomes RlJ.
Therefore, the virtual accelerator pedal signal Sl5 is used as a signal indicating the accelerator position in the control sleeve position calculation circuit 3.
2, thereby entering the idle control state. In this control state, as described above, the engine rotational speed is set to the desired value N by the virtual accelerator pedal signal Sl5. Governor control is performed so that In this way, even if the idle state is detected by the accelerator switch 40, the actual engine speed N is the target idle speed N. If the engine speed is higher than that, the idle control is not started, thereby suppressing the so-called undershoot phenomenon caused by a sudden drop in the rotational speed when the accelerator is suddenly released, such as when revving up. On the other hand, when the accelerator is depressed in the idle state, when the actual accelerator pedal depression amount becomes larger than the virtual accelerator pedal depression amount indicated by the virtual accelerator pedal signal Sl5, the accelerator signal S7 returns to the control sleeve position calculation circuit 3.
2, the control returns to normal governor control. Therefore, when transitioning from the idle state to the running state, it is possible to reliably prevent the rotational speed from decreasing temporarily. According to the present invention, as described above, it is possible to accurately maintain the idle speed at a desired value, and also to prevent a temporary decrease in the engine speed when transitioning from the idle state to the driving state. It is possible to provide an electronically controlled fuel injection device that has advantages such as being able to perform speed regulating control to prevent such occurrence.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a mechanical part of an embodiment of the present invention, FIG. 2 is a plan view of the electromagnetic actuator shown in FIG. 1, and FIG.
This figure is a plan view showing a state in which the position sensor is removed from FIG. 2, and FIG. 4 is a block diagram of the control device of this embodiment. 1...Fuel injection device, 9...Plunger, 17...
- Control sleeve, 18... Electromagnetic actuator, 25... Position sensor, 31... Control device, 32
...Control sleeve position calculation circuit, 33...
Rotation sensor, 34... accelerator pedal position detection circuit,
35... Selector switch, 36, 38... Error amplification circuit, 37... Target idle rotation speed calculation circuit, 39...
- Virtual accelerator pedal position calculation circuit, 40... accelerator switch, 41... switching control circuit, 42... first
Comparator, 43... Second comparator, 44... AND circuit, 45... R-S flip-flop, S1... Rotation signal, S7... Accelerator signal, S8... Target position signal , S9, Sl6... detection signal, SlO, Sl4...
Error signal, Sl3...Target signal, Sl5...Virtual accelerator pedal signal.

Claims (1)

[Scope of Claims] 1. An electronically controlled fuel injection device equipped with a control system that controls the position of a fuel injection amount adjusting member based on an electrical signal indicating operating conditions of an internal combustion engine to obtain desired governor characteristics. , a first calculating means for calculating a target idle speed corresponding to the current operating conditions of the internal combustion engine; a first means for detecting a difference between the target idle speed and the actual speed; a second calculation means for generating a virtual accelerator pedal signal for setting the rotation speed to the target idle rotation speed based on a detection result in the means; and a second calculation means for outputting an accelerator signal according to the actual accelerator pedal operation amount. a switch means capable of selectively applying either the signal or the virtual accelerator pedal signal to the control system as accelerator position information, and detecting whether or not the internal combustion engine is in a desired idle operation state, control means for controlling the switching of the switch means so that when it is determined that the idling state is present, the virtual accelerator pedal signal is selectively output; and when it is determined that the idling state is not present, the accelerator signal is selectively output. A fuel injection device characterized by comprising: 2. The control means includes a first detection means for detecting that the rotation speed of the internal combustion engine has become lower than or equal to the target idle rotation speed, and a first detection means for detecting that the rotation speed of the internal combustion engine has become lower than or equal to the target idle rotation speed; a second detection means for detecting that the accelerator pedal has been depressed; and a second detection means for detecting the virtual accelerator pedal signal at a timing when the rotation speed of the internal combustion engine becomes equal to or less than the target idle rotation speed in response to the detection results by the first and second detection means. and means for switching and controlling the switch means so that the accelerator signal is selected at a timing when the accelerator pedal is depressed to a position equal to or higher than the virtual accelerator pedal position indicated by the virtual accelerator pedal signal. A fuel injection device according to claim 1.