JPS5840026B2 - NinenenkikanyoudenshikitenKajikichiyouseisouchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an electronic ignition timing adjustment device for an internal combustion engine.
The purpose of this invention is to accurately adjust the ignition timing in the entire low-speed rotation region and high-speed rotation region of an internal combustion engine.

FIGS. 1A and 1B are time charts showing a schematic configuration diagram of a conventional device described in Japanese Unexamined Patent Publication No. 49-92430 and its operating principle.

1 is an angular position detection device that detects the angular position of the internal combustion engine crankshaft; 4 is an ignition timing calculation circuit that determines the ignition timing;
2 is an engine current generator that is connected to a detector (not shown) that detects the operating state of the internal combustion engine, and provides an electric current according to the operating state based on the electrical signal of this detector; This is an ignition device that ignites at a determined ignition timing.

Further, Ml and M2 on the time line a shown in FIG. 1B indicate two different rotation angle positions of the crankshaft, T indicates the top dead center, and S indicates the ignition position.

Next, the operation of the conventional device will be explained.

The angular position detection device 1 detects two rotational angular positions Ml and M2 of the crankshaft.

On the other hand, the ignition timing calculation circuit 4 is provided with a capacitor (not shown), which charges this capacitor with a constant current from position M1, stops charging the capacitor at position M2, and at the same time performs constant current discharge. The time point S when the discharge ends is the ignition timing.

At this time, the terminal voltage of the capacitor becomes as shown by the charging/discharging curve C shown by the solid line in FIG. 1B.

In other words, when the capacitor's charging current and discharging current are constant, the ignition timing is constant at the angular position of the crankshaft regardless of the internal combustion engine speed, and the capacitor's discharging or charging current is applied to the internal combustion engine by the engine current generator 2. By changing the ignition timing according to the condition of the internal combustion engine, the ignition timing can be changed according to the condition of the internal combustion engine.

Note that b in FIG. 1B indicates the charging/discharging state of the capacitor.

By the way, in the above-mentioned conventional device, when the rotation speed of the internal combustion engine changes drastically, for example, in a 4-cylinder 4-cycle internal combustion engine, from about 20 Orpm in the cranking state at the time of starting the internal combustion engine to about 600 Orpm at high speed rotation, the rotation speed is about 1: Since the rotation speed changes by a ratio of 30:1, the time to charge the capacitor (the time from angular position M1 to M2) changes at a ratio of about 30:l, and the terminal voltage Vc of the capacitor (as shown in Figure 1B) changes at a ratio of about 30:1. Curve C) similarly changes to approximately 301.

Therefore, if the charging current is reduced at low speed rotation, the terminal voltage Vc of the capacitor will be reduced at high speed rotation. The disadvantage is that it is significantly worse than .

On the other hand, in order to improve the specified accuracy even in high-speed rotation, the capacitor's charging current is increased and the capacitor's terminal voltage V
When c is increased, the terminal voltage of the capacitor becomes saturated as shown by the broken line in Figure 1B at low speed rotation.
There is a drawback that a predetermined ignition timing cannot be obtained.

In order to solve the above-mentioned drawbacks, the present invention uses two capacitors, a first capacitor and a second capacitor, and starts charging the second capacitor when the charging voltage of the first capacitor reaches a predetermined value. After the completion of the discharge, the second capacitor is discharged, and after the second capacitor has finished discharging, the first capacitor is discharged, and the time when this first capacitor has finished discharging is set as the ignition timing, and the charging voltage of the first capacitor is set to a predetermined value. When the ignition timing is not reached, the first capacitor is discharged without charging or discharging the second capacitor, and the ignition timing is calculated at the end of discharge of the first capacitor. A first object of the present invention is to provide an electronic ignition timing adjustment device for an internal combustion engine that can perform good and stable ignition timing adjustment.

Furthermore, the present invention provides a charging current for the second capacitor.

For internal combustion engines, the stability in the low speed range can be further improved by making the discharging current smaller than the charging current and discharging current of the first capacitor, and by making the slope of the charging/discharging state of the second capacitor smaller than that of the first capacitor. A second object is to provide an electronic ignition timing adjustment device.

The present invention will be described below with reference to embodiments shown in the drawings.

In one embodiment shown in FIG. 2, 1 is connected to an angular position detection device for detecting the position of the crankshaft of a 4-cylinder, 4-cycle internal combustion engine, and 2 is connected to a detector (not shown) for detecting the operating state of the internal combustion engine. This engine condition detector supplies a signal according to the operating condition based on the electric signal of this detector, and detects things such as the rotational speed of the internal combustion engine, the intake negative pressure, and the engine cooling water temperature.

The engine state detector 2 is composed of a charge control section 2-1 and a discharge control section 2-2, and even if both of them change according to the operating state of the internal combustion engine, only one of them changes depending on the operating state of the internal combustion engine. It may be configured such that one value is changed accordingly and the other is made to be a constant value.

Reference numeral 100 denotes an ignition timing calculation circuit that determines the ignition timing using a capacitor charging/discharging method, and numeral 3 denotes a known ignition circuit that performs ignition based on a signal obtained by the ignition timing calculation circuit 100.

The ignition timing calculation circuit 100 includes a first integrating circuit 10 having a first capacitor, a second integrating circuit 20 having a second capacitor, a first comparator 30°, a second comparator 40. It is composed of a third comparator 50 and a control circuit 60 that controls the first and second integrating circuits 10 and 20.

The first, second and third comparators 30.degree. 40.50 and the control circuit 60 constitute an ignition signal generation circuit.

A detailed circuit of the apparatus of the present invention having the above structure will be explained with reference to FIG.

The first integrating circuit 10 conducts and interrupts the charging current (ON-OF).
F) Analog switch 11 to set the discharge current to 0N-OF
The analog switch 11 is composed of an analog switch 13 that resets F, a charging resistor 12, a discharging resistor 14, a first capacitor 15, an analog switch 16 that resets the charging charge of the first capacitor 15, a differential amplifier 11, and bias resistors 18 and 19. , 13, and 16 are turned ON when a signal of f+11 level is applied to the gate G, and turned OFF when a signal of "'O" level is applied, and it is preferable to use field effect transistors.

And analog switches 11, 13, charging resistor 12,
The discharge resistor 14 and the engine state detector 2 constitute a first charge/discharge current control circuit.

The second integrating circuit 20 includes an analog switch 21 that turns the charging current 0N-OFF, an analog switch 23 that turns the discharge current 0N-OFF, a charging resistor 22, a discharging resistor 24, a second capacitor 25, and a charge charge of the second capacitor 25. It is composed of an analog switch 26 to be reset, a differential amplifier 27, and bias resistors 28 and 29, and each analog switch 21, 23°26 is connected to the analog switch IL1.
3 and 16 are used.

And analog switches 21, 23, charging resistor 22,
The discharge resistor 24 and the engine state detector 2 constitute a second charge/discharge current control circuit.

The first comparator 30 is composed of an input resistor 31, bias resistors 32 and 33 for setting a set voltage, and a comparator 34, and outputs a signal of 41179 level when the input voltage is higher than the set voltage.

The second comparator 40 is composed of an input resistor 41, bias resistors 42, 43 for setting a set voltage, and a comparator 44, and the set voltage determined by the bias resistors 42, 43 is equal to the set voltage Vref2 of the first integrating circuit 10. It is the same,
When the input voltage is higher than the set voltage, a II I It level signal is output.

The third comparator 50 is composed of an input resistor 51, bias resistors 52 and 53 for setting a set voltage, and a comparator 54.
The set voltage set by the bias resistors 52 and 53 is the same as the set voltage Vref3 of the second integrating circuit 20, and when the input voltage is higher than the set voltage Vref3, e+1
Outputs an n-level signal.

The control circuit 60 includes a capacitor 62 making up a differential circuit,
Resistor 64, diode 63° and capacitor 68, resistor 69, diode 70° NOR circuit 66° 67, NOT circuit 61.71.72 making a R-S flip circuit
．． 74. It is composed of AND circuits 65, 73, and 75.

Note that the output voltage of the charging control section 2-1 of the engine state detector 2 is lower than the set voltages Vref2 and Vref3, and the output voltage of the discharge control section 2-2 is lower than the set voltage Vref2t.
Of course, it should be higher than Vref3.

Further, an embodiment of the detailed circuits of the angular position detecting device 1 and the engine state detector 2 will be explained with reference to FIG.

In the angular position detector 1, 1-1 are arranged at 4 equal intervals on the outer circumference.
The rotor has several protrusions and is fixed to a distributor shaft (not shown) of an internal combustion engine, and rotates together with this distributor shaft.

1-2 and 1-3 are first . The second electromagnetic pickup is opposed to the protrusion of the rotor 1-1.

1-6 and 17 are transistors connected to each electromagnetic pickup 1-2 and 1-3, and 1-4 and 1-5 are resistors.

1-8 and 1-9 constitute a flip-flop circuit with NAND circuits, one input of which is the transistor 1-6.
The other input is connected to the collector of the transistor 1-1.

The rotor 1-1 rotates once in the direction of the arrow for every two revolutions of the crankshaft, and when each protrusion of the rotor 1-1 crosses the electromagnetic pickup 1-2, 1-3, each electromagnetic pickup 1
-2, 1-3 generate a signal that dips from positive to negative.

Therefore, each electromagnetic pickup 1-2, 1-3 detects Ml and M2 for each cylinder of the crankshaft.

When a negative signal is generated in each electromagnetic pickup 1-2, 1-3, each transistor 1-6, 1-7 becomes conductive, and due to the conduction of each transistor 1-6, 1-7, the NAND circuit 1 A flip-flop consisting of -8 and 1-9 is activated, and an output as shown in FIG. 4a is generated in this flip-flop in accordance with the rotational speed of the internal combustion engine.

Further, in the engine state detector 2, the charge control section 2-1 will be explained using the engine speed as a parameter.

The engine speed circuit that differentiates and integrates the output pulse of the angular position detector 1 is composed of capacitors 2-1-1, 2-1-5 and resistor 2.
-1-2.2-1-4, a transistor 2-1-3, and a differential pulse generated by a resistor 2-1-2 and a capacitor 2-1-1 is integrated by a capacitor 21-5.

When the output pulse of the angular position detector 1 falls from 1 to 0, the transistors 2-1-3 are turned on only for a certain time width of the differential pulse, so the transistor 2-1-3 becomes conductive as the engine speed increases. -3 collector potential increases approximately linearly.

This output is input resistance 2-1-6, 2-1-7, 2-1-
8, 2-1-11. 2-112, feedback resistor 2-1-9,
It is coupled to an adder circuit composed of differential amplifiers 2-1-10 and is positively amplified.

Input resistors 2-1-7, 2-1-12 are coupled to responsive circuits for parameters other than the engine speed circuit, such as intake pressure, engine coolant temperature, etc.

The explanation will be omitted here except for the speed circuit.

In addition, the discharge control section 2-2 includes divided resistors 2-2-1, 2-2
-2 and generates a constant voltage.

And when the engine speed is low, the differential amplifier 2-1-10
Since the output voltage of the integrating circuits 10 and 20 is low, the charging current of the integrating circuits 10 and 20 becomes large, and the capacitor charging voltage becomes large and has a high potential.

Furthermore, since the discharge current is constant at this time, the ignition timing is retarded.

Conversely, when the engine speed increases, the output voltage of the differential amplifier 2-1-10 increases, the capacitor charging voltage decreases to a low potential, and the ignition timing advances.

Next, the operation of the apparatus of the present invention having the above structure will be described with reference to the signal waveform diagram of each part shown in FIG.

The angular position detection device 1 emits a rectangular pulse in synchronization with the rotation of the crankshaft of an internal combustion engine (not shown), and is shown in Fig. 4a.
As shown in FIG. 2, a "1" level is generated between <M1 and M2, and a "0" level is generated between 2 and M1, and two pulses of two cycles per rotation are generated.

Then, when the angular position detection device 1 reaches the "1" level, A
The analog switch 11 of the first integrating circuit 10 is turned ON when all the inputs of the ND circuit 65 are "1'1" level.
Then, by applying an "ON" level signal to the input of the AND circuit 75 via the inverter 61, the analog switch 13 is turned off, and at this time, the output of the second comparator 40 becomes as shown in FIG. 4d. and < el 1 n
level, the analog switch 16 is turned off via the inverter 71, and the engine state detector 2
becomes conductive with the input of the charging control unit 2-1, and the charging resistor 12
Through this, the first capacitor 15 is charged as shown in FIG.

The output is compared with the set voltage ref1 of the first comparator 30 and the set voltage Vref2 of the second comparator 40, respectively.

Further, in this case, the bias potential of the first integrating circuit 10 is the same potential as the set voltage Vref2.

Further, the line between Vcc and Gnd shown in FIG. 3 is connected between the terminals of the power supply.

Therefore, when the first capacitor 15 starts charging, the second comparator 40 reaches the °1'1' level.

Then, the output of the first integrating circuit 10 is the set voltage Vref1
When it becomes larger, the first comparator 30 becomes a level, and a positive differential pulse is generated at the differential circuit output f of the control circuit 60 as shown in FIG.
The output is shown in the fourth diagram and is set to <: ``1'' level.

As a result, the analog switch 11 is turned OFF, and the output of the first integrating circuit 10 is held at the set voltage Vref1 as shown in FIG.

Also, at that time, the analog switch 21 of the second integrating circuit 20
is turned ON, and charging of the capacitor 25 via the charging resistor 22 begins as shown in FIG. 4C.

Its output is the set voltage V r e f3 of the third comparator 50
compared to

Further, in this case, the bias potential of the third comparator 50 is the same potential as the set voltage Vref3, as described above.

Therefore, when the second capacitor 25 starts charging, the output e of the third comparator 50 becomes as shown in FIG.
l It becomes the level.

When the angular position detection device 1 reaches the OII level, the output g of the differential circuit generates a positive differential pulse as shown in Figure 4g, and the output of the R-S flip-flop is inverted as shown in Figure 4. , the analog switch 21 of the second integrating circuit 20 is turned OFF, and the output i of the AND circuit 73 becomes t<"1" level as shown in FIG. It becomes electrically connected to the discharge control section 2 - 2 of the state detector 2 and starts discharging the second capacitor 25 via the discharge resistor 24 .

Then, when the charge stored in the second capacitor 25 gradually decreases and becomes lower than the set voltage Vref3, the third comparator 50 becomes the "0" level, and the analog switch 2
3 is turned off, the analog switch 26 is turned on, the terminals of the second capacitor 25 are short-circuited, and the output potential is held at the set voltage Vref3.

At the same time, the analog switch 13 of the first integrating circuit 10
is turned ON, the charge of the first capacitor 15 that has been held from a while ago begins to discharge through the discharge resistor 14, and when the voltage becomes lower than the set voltage V r e f2, the output of the second comparator 40 is inverted to the Ol+ level. Analog switch 13 is 0FF1 Analog switch 16 is ONt,
The output of the first integrating circuit 10 settles to the set voltage Vref2.

Then, the next time the angular position detecting device 1 reaches the "1" level, the same operation as described above is repeated.

Next, when the high-speed rotation range is reached, the rotation angle detection device 1 reaches "0" level before the output of the first integrating circuit 10 reaches the set voltage Vrefl, and the second integrating circuit 20 is not driven. Analog switch 13 of first integrating circuit 10
turns ON and discharge starts.

Here, when the state of the internal combustion engine is constant and the output of the engine state detector 2 is constant, the first capacitor 15. Since the charging current and discharging current of each of the second capacitors 25 are constant, the angular position at the end of discharge is constant regardless of the rotation speed.

Further, even in a region where the speed is high and the second capacitor 25 is not used, the speed remains constant.

Here, if the charging/discharging current of the second integrating circuit 20 is reduced in the same ratio as the charging/discharging current of the first integrating circuit 10, the charging/discharging of the second capacitor 25 becomes longer, and even at extremely low speed, the second capacitor 25 from being saturated.

At this time, the resistance values of the charging and discharging resistors 22 and 24 of the second integrating circuit 20 may be increased by the same ratio as the resistance values of the charging and discharging resistors 12 and 14 of the first integrating circuit 10, respectively.

As a result, at low speeds, the second capacitor 25 is used and the charging/discharging time is extended to stabilize the ignition timing at low speeds, and when the speed is high and the second capacitor 25 is not used, the charging/discharging time of the first capacitor 15 is shortened. , the ignition timing is stabilized by a first integrating circuit 10 with good rise and fall.

Now, with the charge control circuit 2-1 constant, the discharge control section 2-2
When the discharge potential is made smaller, the angular position at the discharge end point m3 becomes the lag side, and conversely, when the discharge potential is made higher, the angular position becomes the advance side.

In addition, conversely, with the discharge control section 2-2 constant, the charge control section 21
Similarly, by changing the charging potential of , it is possible to move it to the leading side or to the lagging side.

Therefore, if the engine state detector 2 controls charging and discharging with the discharge end point m3 as the ignition timing, any advance angle characteristic can be obtained.

Therefore, at the time m3 when the discharge of the first integrating circuit 10 ends, the output of the second comparator 40 is reversed from the level to the NO1 level, so that signal is connected to the ignition circuit 3 to ignite.

In the above-described embodiment, the integrating circuit is configured by a Miller integrating circuit, but it can be similarly configured by using an ordinary RC integrating circuit, a bootstrap type integrating circuit, or the like.

Furthermore, the charging and discharging times of the first integrating circuit 10 and the second integrating circuit 20 are adjusted using charging/discharging resistors 12° 14.22, 24 and analog switches 11, 13° 21.23, but the engine state detection The same effect can be achieved by directly adjusting the output voltage of the engine state detector 2 within the engine state detector 2.

In the embodiment described above, when the charging voltage of the capacitor 15 of the first integrating circuit 10 exceeds a predetermined value, the charging voltage of the capacitor 15 is continued to be held. is the set voltage Vre
fl itself, instead of holding the charging voltage of the capacitor 15, it is also possible to use the set voltage Vrefl to instantaneously charge the other integrating circuits. capacitor 1
When the charging voltage of capacitor 5 exceeds a predetermined value, this capacitor 1
It is also possible to reset the charge of No. 5 and make the first integrating circuit also serve as the second integrating circuit.

In addition, in the embodiment described above, two capacitors 1
Although 5 and 25 capacitors are used, the device of the present invention can be constructed by further dividing the capacitors and using three or more capacitors.

As explained above, in the device of the present invention, the first capacitor is connected to the angular position detecting device, and the capacitor is charged by the first charging/discharging current control circuit in response to the first detection signal generated in the angular position detecting device. and when the amount of charge reaches a preset value, charging is stopped to charge the second capacitor, and when a second detection signal is generated in the angular position detection device, the second capacitor is discharged, After the discharge of the second capacitor is completed, the first capacitor is discharged, and an ignition signal is generated with the end of the discharge as the ignition timing, and the angular position detection device When the second detection signal is generated in Stable ignition timing up to high speeds can be obtained, and by using two capacitors, the terminal voltage of the capacitor is essentially equal to the sum of the terminal voltages of the two capacitors, making it possible to achieve stable ignition timing in the low speed range without reducing accuracy in the high speed range. It has the excellent effect of increasing stability.

Furthermore, since the charging/discharging current of the second capacitor by the second charging/discharging current control circuit is made smaller by the same ratio than the charging/discharging current of the first capacitor by the first charging current control circuit, the capacitor This has the excellent effect of further increasing stability in the low speed range without saturating the speed.

[Brief explanation of drawings]

1A and 1B are block diagrams showing conventional devices and their time charts, FIG. 2 is a block diagram showing an example of an implementation of the device of the present invention, and FIG. 3 is a detailed circuit of the device of the present invention shown in FIG. 1. FIG. 4 a to i are signal waveform diagrams of various parts to explain the operation of the device of the present invention shown in FIG. 3, and FIG. FIG. 2 is an electrical circuit diagram showing an example of a detailed circuit of a state detector portion. 1... Angular position detection device, 2. lL12,13
゜14... Engine state detector, analog switch, charging resistor, analog switch, discharging resistor, 2, 21, 22, 23 ゜24.
...Engine state detector, analog switch, charging resistor, analog switch, discharging resistor, 15, 25... First and second capacitors, 30, which constitute the second charge/discharge current control circuit 40, 50, 60... First, second, and third comparators and control circuits that constitute the ignition signal generation circuit.

Claims (1)

[Scope of Claims] 1. An electronic ignition timing adjustment device for an internal combustion engine that electronically adjusts the ignition timing in an ignition device of the internal combustion engine, which comprises the following. (a) An angular position detection device that detects a plurality of different rotational angular positions of an internal combustion engine and generates a detection signal; (b)
a first capacitor, (C) a first charging/discharging current control circuit connected to this first capacitor and charging/discharging this first capacitor with an arbitrary charging current and discharging current, (d) a second capacitor, (e) this a second charging/discharging current control circuit connected to a second capacitor and charging/discharging the second capacitor with arbitrary charging current and discharging current; (f) the first and second capacitors, the angular position detection device, and the second capacitor; 1. The first capacitor is connected to a second capacitor charging/discharging current control circuit, and the first capacitor is charged by the first charging/discharging current control circuit in response to a first detection signal generated in this angular position detection device, and the amount of charge is When reaches a preset value, charging is stopped and the second capacitor is charged by the second charging/discharging current control circuit, and when a second detection signal is generated in the angular position detecting device, the second capacitor is charged. The second capacitor is discharged by a discharge current control circuit, and after the discharge of the second capacitor is finished, the first capacitor is discharged by the first capacitor charging/discharging current control circuit, and the ignition signal is set at the end of the discharge as an ignition timing. When a second detection signal is generated in the angular position detection device before the charge amount of the first capacitor reaches the set value, the first capacitor is stopped from the time when the second detection signal is generated. An ignition signal generation circuit that generates an ignition signal by causing a discharge and using the end of the discharge as the ignition timing. 2. The charging/discharging current of the second capacitor by the second charging/discharging current control circuit is made smaller by the same ratio than the charging/discharging current of the first capacitor by the first charging/discharging current control circuit. An electronic ignition timing adjustment device for an internal combustion engine according to claim 1.