JP3059448B2 - Stop control device for internal combustion engine - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a stop control device for an internal combustion engine, and more specifically, to a fuel supply to an internal combustion engine is reliably stopped after a key switch-off. The present invention relates to a stop control device for an internal combustion engine which controls a governor actuator of a fuel injection device.

2. Description of the Related Art Conventionally, in an electronic governor for adjusting a fuel injection amount supplied from a fuel injection pump to a diesel engine, an actuator for controlling a position of a fuel adjusting member of the fuel injection pump. A so-called voice coil type actuator having a movable coil which is resiliently urged by an appropriate spring is used to apply a current signal related to the engine speed to the movable coil, thereby reducing the electromagnetic force generated by the current signal. There is known a configuration in which the fuel adjusting member is positioned at a position where the above-mentioned resilient urging force is balanced. In this type of electronic governor,
The spring setting force is small enough to support the weight of the moving coil. Therefore, if the actuator cannot maintain the required mounting state for some reason, for example, when the device is rolled over, the key is set. -Even if the switch is turned off, the fuel injection member cannot be positioned at the zero injection position, and there is a problem that the engine may not be able to be stopped.

In order to solve this problem, a relay circuit which can operate the control unit only for a predetermined time even if the key switch is turned off is provided between the power supply and the control unit, and a relay circuit capable of delay operation is provided. Rear control
The present applicant has proposed a configuration in which Lulac is forcibly pulled to the full fuel deceleration direction, whereby the engine can be reliably stopped (Japanese Utility Model Laid-Open No. 61-80337).

(Problems to be Solved by the Invention) However, in the proposed configuration, there is a danger that the engine will run away if another failure is superimposed when the contacts of the relay circuit are fixed, and the failsafe However, there is a problem that it cannot be said that this is sufficient.

An object of the present invention is to provide an improved stop control device for an internal combustion engine, which can solve the above-mentioned problems in the prior art.

(Means for Solving the Problems) In order to solve the above problems, the present invention provides a moving coil,
A linear motor type electromagnetic actuator comprising a spring means for biasing the movable coil so as to cancel the weight of the movable coil, wherein a fuel for an internal combustion engine fuel injection pump is provided in accordance with a direction in which the movable coil is energized. An internal combustion engine stop control device provided with an electronic speed governor for controlling a position of an adjusting member, wherein the output voltage from a generator driven by the internal combustion engine in response to a key switch being turned off is used. An electric current is applied to the movable coil, and the electromagnetic actuator is driven so that the fuel adjusting member is at the non-injection position.

(Operation) In response to the key switch being turned to the off position, the actuator is controlled by the output voltage of the generator so that the position of the fuel adjusting member becomes the zero injection position. Therefore, regardless of the position of the actuator, the fuel injection amount is forcibly set to zero by the key switch-off, and the rotational speed of the engine is reduced. As a result, the output voltage level of the L terminal decreases, and the operating state of the actuator is released.

(Example) Hereinafter, one example of illustration is described in detail.

FIG. 1 shows an embodiment of an internal combustion engine stop control device according to the present invention. An electronic speed governor 1 indicated by reference numeral 1 includes an electromagnetic actuator 4 connected to a control rack 3 of a row type fuel injection pump 2 and a control unit 5 for driving and controlling the electromagnetic actuator 4. And The control unit 5 is supplied with power from the battery 7 when the key switch 6 is turned on. A pulse signal PS for driving and controlling the electromagnetic actuator 4 is output from the control unit 5, and the pulse signal PS is the L signal of the generator 9.
It is input to a stop control circuit 8 that operates in response to the output voltage _VL from the terminal. The drive circuit 10 responds to the signal from the stop control circuit 8 and supplies an exciting current to the exciting coil of the electromagnetic actuator 4 as described later.

The electromagnetic actuator 4 has a case 11 fixed to the fuel injection pump 2, and one end of the control rack 3 is received in the case 11. Control rack 3
Are supported by a bearing 12 formed on the case 11, and in a groove 14 formed at one end of the control rack 3, a pin is implanted on a link 15 having an intermediate fulcrum on the case 11. 15a is involved. A pin 15b provided at the other end of the link 15 is a closed cylindrical movable body 17 of the linear motor 16.
Into the groove 18a of the locking member 18 fixed to the upper end of the lock member 18. The movable body 17 is provided with an exciting coil 19, and a drive current corresponding to the pulse signal PS from the control unit 5 is supplied to the exciting coil 19 as described later.

The link 15 is configured to move the control rack 3 in the fuel decreasing direction when the movable body 17 moves in the direction of gravity.

The linear motor 16 has a bottomed cylindrical magnetic material (yoke) 20.
A cylindrical permanent magnet 21 is fixed to an inner peripheral portion thereof such that one of the magnetic poles N is in contact therewith. Magnetic material
A columnar magnetic body (pole) 22 is in contact with the inner bottom of 20 and is fixed with bolts 23. Permanent magnet 21 and magnetic body 22
An annular space 24 is provided between the movable space 17 and the movable space 17 according to the amount of the excitation current I supplied to the excitation coil 19 of the movable body 17 according to the drive pulse signal DS. Be withdrawn.

This exciting current I is a signal that changes in both positive and negative directions around zero as shown in FIG. 2B in response to the pulse signal PS shown in FIG. In, the ratio of the period flowing in the positive direction to the period flowing in the negative direction is controlled. The amount of current supplied to the exciting coil 19 is determined by this ratio.

A spring receiver 25 is fixed to the control rack 3, and a resilient coil spring 13 is interposed between the spring receiver 25 and the inner lid of the case 11. The coil spring 13 absorbs the play at the engaging portion between the link 15 and the movable body 17 and applies a necessary and sufficient force to the control rack 3 to set the movable body 17 at the position shown in the figure when not driven. A spring having a small spring force that does not substantially cause resistance to driving of the control rack 3 by the linear motor 16 is used. A force due to its own weight is constantly applied to the movable body 17 in the direction of gravity, and when a drive current I of the form shown in FIG. A force corresponding to the difference between the driving force and its gravity is output as the driving force of the linear motor 16 to move the control rack 3. Here, the amount of current supplied to the excitation coil 19 is in accordance with the ratio of the period during which the current flows in the positive direction to the period during which the current flows in the negative direction in one cycle of the drive current I. Direction.

The locking member 18 is provided with a rod 26 for position detection, and a detection coil 27 is mounted outside the case on an extension of the rod 26, and a tip 26a of the rod 26 is provided inside the detection coil 27. I'm stuck. Therefore, the tip 26a is
The detection coil 27 is displaced in accordance with the displacement of the position of the rack 3, and the inductance value of the detection coil 27 becomes a value corresponding to the position of the control rack 3 at each time. As described above, the position sensor 28 for detecting the position of the control rack 3 including the detection coil 27 and the rod 26 is configured. The detection coil 27 of the position sensor 28 is connected to a detection circuit 29, and the detection circuit 29 outputs a position signal PS indicating the position of the control rack 3.

The position signal PS is input to the control unit 5 as a position feedback signal, and a pulse signal PS for positioning the control rack 3 at a required position is output from the control unit 5. When the key switch 6 is closed, the pulse signal PS is directly applied to the drive circuit 10 through the stop control circuit 8, and the positioning control of the control rack 3 is fed back in response to the pulse signal PS. It is performed by control.

The stop control circuit 8 responds to the turning off of the key switch 6 to output the output voltage V _L from the L terminal of the generator 9.
And a signal for driving the electromagnetic actuator 4 so that the control rack 3 is fully pulled in the fuel decreasing direction based on the control signal, so that when the key switch 6 is turned off for a while thereafter, The supply of the fuel is reliably stopped using the output voltage _VL, and the rotation of the engine is stopped.

Next, referring to FIG. 3, the stop control circuit 8 and the drive circuit
The respective circuit configurations of 10 and their operations will be described.

The stop control circuit 8 includes diodes 81 and 82 and a gate circuit 8.
3 to 86 are connected as shown. Daio
The anode of the node 81 is connected to the positive electrode of the battery 7 via the key switch 6, the anode of the diode 82 is connected to the L terminal of the generator 9, and the pulse signal PS is gated. Circuit 8
5,86 are applied to one input.

On the other hand, the driving circuit 10 includes PNP transistors 101 and 102 and NP
N transistors 103 and 104 are bridge-connected
A first control transistor 105 for simultaneously turning on the transistor 101 and the NPN transistor 104 and a second control transistor 106 for simultaneously turning on the PNP transistor 102 and the NPN transistor 103 are connected as shown. I have. The emitters of the NPN transistors 103 and 104 are connected A commonly - are scan, the emitters of the PNP transistors 101 and 102 are commonly connected, diode via a line L ₁ - de 81 cathode - is connected to the de ing.
Therefore, when the key switch 6 is on, the voltage of the battery 7 is supplied to the drive circuit 10 via the key switch 6 and the diode 81. The output voltage _{VL is} also supplied to the drive circuit 10 via the diode 82. Therefore, if the engine is rotating even if the key switch 6 is turned off, the output voltage _VL is changed according to the rotation state. Output voltage V _L
Is supplied to the drive circuit 10.

Of the first control transistor 105 base - scan the gate via a line L ₂ - is connected to the output of the bets circuit 84, base of the second control transistor 106 - Output DOO circuit 86 - scan via the line L ₃ gate It is connected to the. And PNP transistor 101 and NPN
Connection point A with transistor 103 and PNP transistors 102 and N
Between a connection point B between the PN transistor 104, the line L _a,
The excitation coil 19 through a L _b is connected.

Therefore, when the output of the gate circuit 84 goes high and the first control transistor 105 is turned on, the PNP transistor 101 and the NPN transistor 1 respond in response to this.
04 becomes conductive, and the exciting current flows through the exciting coil 19 in the direction of arrow X. On the other hand, when the output of the gate circuit 86 goes high and the second control transistor 106 is turned on, the PNP transistors 102 and 103 are turned on in response to this, and the exciting coil 19 is turned on by an arrow. An exciting current flows in the Y direction. Here, when the average value of the exciting current increases in the X direction, the control rack 3 moves in the fuel decreasing direction, while when the average value increases in the Y direction, the control rack 3 moves in the fuel increasing direction. , An electromagnetic actuator 4.

Next, the operation of the stop control circuit 8 when the key switch 6 is turned on will be described. In this case, since the terminal voltage of the battery 7 is applied to the inverting input terminal of the gate circuit 83, the output level of the gate circuit 83 becomes "L" regardless of the level state of the output voltage _VL . Therefore,
Each of the gate circuits 85 and 86 receiving the "L" level state at the inverting input terminal is opened and closed in response to the level of the pulse signal PS applied to the other input. Gate - so DOO circuit 86 has received the pulse signal PS at the noninverting input a signal resulting from the line L ₃ is a pulse signal of the pulse signal PS and the same phase. On the other hand, the gate circuit 85 outputs the pulse signal PS
Since received at the inverting input of a signal resulting from the line L ₂ is a pulse signal PS and 180 ° phase different pulse signals PS '
Becomes

These pulse signals PS 'and PS are applied to the first and second control transistors 105 and 106, and the first and second control transistors 105 and 106 are turned on alternately. As a result, the pulse signal PS shown in FIG. In response to the application from the control unit 5, the exciting current I shown in FIG. As a result, the pulse signal
The position of the control rack 3 is controlled by the duty ratio of the PS.

In this control state, when the key switch 6 is turned off, the output level of the gate circuit 83 is determined according to the level state of the output voltage _VL . Key switch 6
Immediately after turning OFF, the internal combustion engine is still rotating and the level of the output voltage _VL is high, so that the output level of the gate circuit 83 changes in response to the key switch 6 being turned off. It becomes "H". Thus, gate - output level Both "L" bets circuit 85 and 86, the level of the line L ₂ becomes "H", a line L ₃ level is "L".

As a result, the first control transistor 105 is held in a conductive state and the second control transistor 106 is held in a non-conductive state, so that an exciting current flows continuously through the exciting coil 19 in the direction of arrow X, and the control rack 3 is an electromagnetic actuator
The nozzle 4 is positioned at the non-injection position. However,
The rotation of the engine gradually decreases, leading to the stop of the rotation of the engine,
On the way, the level of the output voltage _VL becomes zero, and the power supply to the drive circuit 10 and the control thereof are stopped.

As described above, in response to the OFF operation of the key switch 6, the drive control of the electromagnetic actuator 4 is performed by the output of the L terminal of the generator driven by the internal combustion engine, and the control rack 3 is not injected. Since the rotation of the engine is surely stopped by positioning it in the state, even if the attitude of the electromagnetic actuator 4 changes variously, the key is kept.
In response to the turning-off operation of the switch 6, the supply of fuel can be reliably stopped, and the rotation of the internal combustion engine can be stopped. Furthermore, since the control rack is positioned at the non-injection position by using the voltage output only when the engine is rotating, the power supply is automatically stopped when the rotation of the engine is stopped. There is no danger of runaway of
Extremely safe and reliable engine stop control can be performed.

Although the present invention has been described with reference to one embodiment, the present invention is not limited to the configuration of this embodiment. For example, a microcomputer having functions equivalent to those of the stop control circuit 8 shown in FIG. May be realized by executing an appropriate program.

(Effect of the Invention) According to the present invention, as described above, in response to the turning-off operation of the key switch, the fuel adjustment member is forcibly moved to the non-injection position using the output from the generator driven by the internal combustion engine. Since the electromagnetic actuator is controlled to move to the position, even if the self-weight of the movable coil is not canceled by the spring means because the posture of the electromagnetic actuator is not in the normal state, the rotation stop control of the engine can be performed safely and reliably. Can do it.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIGS. 2 (a) and 2 (b) are waveform diagrams of signals of respective parts of the apparatus of FIG. 1, and FIG. 3 is a diagram of FIG. FIG. 3 is a detailed circuit diagram of a main part of the device. 1 ... electronic governor, 2 ... row type fuel injection pump, 3 ...
... Control rack, 4 ... Electromagnetic actuator, 6 ...
... key switch, 8 ... stop control circuit, 9 ... generator,
PS: pulse signal, I: excitation current, V _L: output voltage.

Continuation of the front page (56) References JP-A-55-125339 (JP, A) JP-A-62-55428 (JP, A) JP-A-60-178938 (JP, A) JP-A-50-97730 (JP, A) , A) Fully open 1975-1135 (JP, U) Fully open, 53-101919 (JP, U) Fully open, 1-95545 (JP, U) Fully open, 61-80337 (JP, U) 60-23472 (JP, Y2) (58) Fields investigated (Int. Cl. ⁷ , DB name) F02D 1/00-45/00

Claims (1)

(57) [Claims] 1. A linear motor type electromagnetic actuator comprising a movable coil and spring means for biasing the movable coil so as to cancel the weight of the movable coil,
In response to a key switch being turned off, a stop control device for an internal combustion engine including an electronic speed governor that controls a position of a fuel adjusting member of a fuel injection pump for an internal combustion engine in accordance with a direction of energization of the movable coil. Current flowing through the movable coil by an output voltage from a generator driven by the internal combustion engine, and the electromagnetic actuator is driven such that the fuel adjusting member is at a non-injection position. Stop control device.