JPS5833393B2 - Ninenenkikanyoudenshishikitenkajikichiyouseisouchi - 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 Patent Application Laid-Open 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;
Reference numeral 2 is connected to a detector (not shown) that detects the operating state of the internal combustion engine, and an electrical signal from this detector is used to determine the operating state number (an engine current generator that provides a corresponding current); 3 is the ignition timing calculation circuit 4; This is an ignition device that ignites at the ignition timing determined by.

In addition, Ml and M2 on the time line a shown in FIG. 1B are two different rotation angle positions of the crankshaft, T is top dead center, and 8
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), and this capacitor is charged with a constant current from position M1, and charging of the capacitor is stopped at position M2, and at the same time, constant current discharge is performed, and the discharge is completed. The time point S is set as 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.

However, in the conventional device described above, when the rotation speed of the internal combustion engine changes drastically, for example, in a 4-cylinder 4-cycle internal combustion engine, the rotation speed is approximately 1=1= from about 200 rpm in the cranking state at the time of starting the internal combustion engine to about 600 rpm in the high speed rotation. Since the rotation speed changes by a ratio of 30, the time to charge the capacitor (time from angular position M1 to M2) changes by a ratio of approximately 30=1, and the capacitor terminal voltage Vc (as shown in Figure 1B) Curve C) likewise varies by approximately 30:1.

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 is configured such that when the charge amount of the capacitor is above a predetermined amount, the charging/discharging current is reduced by a predetermined ratio compared to when it is not above the predetermined amount. This is an electronic ignition timing adjustment for internal combustion engines that eliminates the above disadvantages by shortening the charging and discharging time in the high speed range, and allows accurate and stable ignition timing adjustment even at low and high speeds. The purpose is to provide a 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. , is an engine condition detector that forms a charging/discharging control circuit that supplies signals according to the operating status using electrical signals from this detector and generates charging/discharging signals for the capacitor.What it detects is the rotational speed of the internal combustion engine and the intake negative pressure. , cooling water temperature, etc.

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 an integrating circuit 10, a first comparator 30 forming a charge amount detection circuit for detecting the amount of charge of a capacitor provided in this integrating circuit 10, a second comparator 40, and an integrating circuit. It is composed of a control circuit 50 that controls charging and discharging of a capacitor provided in 10.

The second comparator 40 and the control circuit 50 constitute an ignition signal generation circuit.

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

The integrating circuit 10 includes an analog switch 1L12, 17°19 which is turned on by a "1" signal, charging resistors 13, 14, discharging resistors 18, 20° bias resistor 2L22, a capacitor 16,
Consisting of a differential amplifier 23, the analog switch 11 is conductive (ON) during charging, and the analog switch 17 is turned ON during discharging.
is turned on, and when the amount of charge in the capacitor 16 is greater than or equal to a predetermined amount, the analog switches 12 and 19 are cut off (off) L, and when the capacitor 16 is reset, the analog switch 15 is turned on.

Preferably, these analog switches use field effect transistors.

The input voltage of the capacitor 16 is set to the reference voltage vref2 determined by the bias resistor 21°22.
When the voltage is lower than ref2, it is charged, and when it is higher than the reference voltage vref2, it is discharged.

Therefore, the output voltage of the charging control section 2-1 of the engine state detector 2 is lower than the reference voltage vref2, the output voltage of the discharging control section 2-2 is higher than the reference voltage vref2, and the output of the integrating circuit 10 is lower than the reference voltage vref2. It rises to the positive side during time and falls to the negative side during discharge.

The first comparator 30 has an input resistor 31. bias resistor 32,
33, comparator 34, bias resistors 32, 33
The amount of charge in the capacitor 16 is detected based on the set voltage vrefl determined by , and when the input voltage is higher than vrefl, the first comparator 30 is at the "on level", and when it is lower, the first comparator 30 is at the "'1" level.

Second comparator 40 input resistor 41. Consists of bias resistor 42°43 and comparator 44, bias resistor 42°43
The set voltage determined by is the same as the reference voltage vref2 of the integrating circuit 10, and the input voltage is the reference voltage vr.
If it is higher than ef2, it is n1tp level, and if it is lower, it is '°0'' level.

The control circuit 50 includes a NOT circuit 5L52, an AND circuit 53,
Consists of 54.

Ba is a battery.

Then, analog switches 12, 19 and input resistor 14.
20 constitutes a charge/discharge current reduction circuit.

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.
A rotor (not shown) of an internal combustion engine with several protrusions
It is fixed to the IJ Buke shaft and rotates together with this distributor shaft.

Reference numerals 1-2 and 1-3 denote first and second electromagnetic pickups which are arranged at a predetermined angle offset in the circumferential direction of the rotor 1-1, and are opposed to the protrusion of the rotor 1-1.

1-6, 1-7 are transistors connected to each electromagnetic pickup 1-2, 1-3, and 1-4, 15 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 transistor 1-7.

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 produces 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 the NAND circuit 1 is turned on by the conduction of each transistor 1-6, 1-7. 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.

Furthermore, 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 consists of a capacitor 2-1-1゜2-1-5 and a resistor 2.
-1-2.2-1-4, a transistor 21-3, and a differential pulse generated by a resistor 2-1-2 and a capacitor 2-1-1 is integrated by a capacitor 2-1-5.

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 as the engine speed increases, the transistors 2-1-3 are turned on. The collector potential of 1-3 increases approximately linearly.

This output is input resistance 2-1-6.2-1-7.2-1-
8.2-1-11゜2-1-12, feedback resistor 2-19,
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. Further, the discharge control section 2-2 is composed of divided resistors 2-2-1 and 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 is low, the charging current of the integrating circuit 10 becomes large, and the capacitor charging voltage becomes thick 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.
``1'' level between <M1 and M2, M2~~M
It emits a "0" level for one period and generates two pulses of two cycles per rotation.

When the angular position detection device 1 reaches the "1" level, the analog switch 11 of the integrating circuit 10 is turned on, and at this time, the output of the first comparator 30 reaches the "1" level as shown in FIG. 4C. Therefore, analog switch 1
2 and 19 are also ONL, and since the outputs of both AND circuits 53 and 54 are at "0" level, analog switches 15 and 1
7 is turned OFF, and the charging control section 2- of the engine state detector 2 is turned OFF.
1, and the capacitor 16 is charged through the charging resistors 13 and 14.

Its output is the set voltage vrefl of the first comparator 30,
They are each compared with the set voltage vref2 of the second comparator 40.

As shown in Fig. 4, the output of the integrating circuit 10 rises to the positive side when the charging state is reached, so as shown in Fig. 4 d.
As shown in , the output of the second comparator 40 will soon become 1''.
become the level.

When the angular position detector 1 is inverted to the ``0'' level as shown in FIG. 4a at the time M2 shown in FIG. 4, the analog switch 11 is turned OFF and the NOT circuit 5 is turned off.
By applying a 1" level signal to the AND circuit 54 through 1, a 1" level signal is generated in the AND circuit 54, and the analog switch 17 is turned on.
Then, the capacitor 17 starts discharging by the charging control section 2-2 through the discharging resistor 18.20, and the output of the integrating circuit 10 falls to the negative side.

When the voltage of the capacitor 16 becomes lower than vref2, the output of the second comparator 40 becomes ``0'' level as shown in FIG. 4d at the time m3 shown in FIG. 4, and the analog switch 17 is turned OFF. The analog switch 15 for resetting the capacitor 16 is made conductive to short-circuit the terminals of the capacitor 16, and the output of the integrating circuit 10 is held at the reference voltage vref2.

Next, at the time Ml shown in FIG. 4, when the angular position detector reaches the 1" level as shown in FIG. Repeat the above operation including charging No. 16.

Furthermore, when the engine speed is in a low speed range, the capacitor 16 is rapidly charged, and the output of the integrating circuit 10 becomes higher than the set potential vref 1 of the first comparator 30 before the angle detecting device 1 reaches the "0" level. , the first comparator 30 is °゛0''
0'' level, the analog switches 12 and 19 are turned off, and there is only one charging resistor 13, which reduces the charging current and slows down the rise of the capacitor 16.

Then, the angular position detector 1 is set to 0°, the analog switch 11 is set to 0FFL, and the analog switch 17 is turned on to start discharging.

At this time, the output of the first comparator 30 is always at the 0''0'' level, so the analog switch 19 is OFF and there is only one discharge resistor 18, and the capacitor 16 starts discharging slowly.

Then, when the output of the integrating circuit 10 becomes smaller than the set voltage vrefl of the first comparator 30, the output of the first comparator 30 is inverted to the "1" level, and the analog switch 12,
19 is turned ON, a discharge resistor 20 is added, and the discharge of the capacitor 16 quickly falls.

Here, when the state of the internal combustion engine is constant and the output of the engine state detector 2 is constant, a triangle formed between Ml and ml shown in FIG. 4 and m2 and m3 are formed. the triangle formed between ml and M2, and the triangle formed between ml and M2
Since the triangles formed between and m2 are each in a proportional state, the angular position at the end of discharge is constant regardless of the rotation speed.

Now, if the output voltage of the charge control section 2-1 is kept constant and the 4th discharge position of the discharge control section 2-2 is made smaller, the angular position at the discharge end point m3 will be on the lag side, and conversely, if the 4th discharge position is kept high As you go, you will be on the advancing side.

Conversely, by keeping the output voltage of the discharge control section 2-2 constant and changing the charging potential of the charge control section 2-1, it is possible to similarly move the battery to the leading side or the delayed side.

Therefore, if the charging and discharging are controlled by the engine state detector 2 with the discharge end point m3 as the ignition timing, arbitrary ignition advance characteristics can be obtained.

Therefore, at the end of discharge of the integrating circuit 10 m3, the output of the second comparator 40 is inverted from the 61'' level to the II O'' level, so that signal is connected to the ignition circuit 3 and ignited.

In the above-described embodiment, the integrating circuit is configured with a Miller integrating circuit, but it can be similarly configured using other integrating circuits such as a normal RC integrating circuit or a bootstrap.

In addition, the charging resistor 14 is used to adjust the charging and discharging time of the capacitor 16.
, 20 and analog switches 12 and 19. However, in the engine condition detector 2, the circuit is configured to reduce the output voltage of the engine condition detector 2. A charge/discharge current reduction circuit may also be used.

As described above, in the device of the present invention, the capacitor is connected to the angular position detecting device, and when the first detection signal is generated in the angular position detecting device, the capacitor is charged by the charge/discharge control circuit, and an ignition signal generation circuit that discharges the capacitor by the charge/discharge control circuit when a second detection signal is generated in the position device, and generates an ignition signal with the end of the discharge as the ignition timing; a charge amount detection circuit; and the charge/discharge control circuit. is connected to a control circuit, and when the charge amount detection circuit detects that the charge amount of the capacitor is a predetermined amount or more, the charging current and the discharging current are reduced by a predetermined ratio compared to when the charge amount is not the predetermined amount or more. Since it is equipped with a charging/discharging current reduction circuit, it is possible to stably determine the ignition timing without saturating the capacitor even in the low speed range, and at the same time, in the high speed range, it is possible to determine the ignition timing stably without saturating the capacitor. Since it is used, it has the excellent effect of being able to calculate the ignition timing with high accuracy.

[Brief explanation of the drawing]

Fig. 1 At B is a block diagram showing a conventional device and its time chart, Fig. 2 is a block diagram showing an embodiment of the inventive device, and Fig. 3 is a detailed circuit diagram of the inventive device shown in Fig. 2. Electrical wiring diagram, Figures 4a to 4e are signal waveform diagrams of various parts used to explain the operation of the device of the present invention shown in Figure 3, and Figure 5 shows the angular position detection device and engine state detection in the device of the invention shown in Figure 3. FIG. 2 is an electric circuit diagram showing an example of a detailed circuit of a device portion. DESCRIPTION OF SYMBOLS 1... Angular position detection device, 2... Engine state detector constituting a charging/discharging control circuit, 3... Ignition circuit, 12゜1
9.14, 20...Analog switch and input resistor forming a charge/discharge current reduction circuit, 16...Capacitor, 3
0...First comparator forming a charge amount detection circuit, 40.5
0: A second comparator and control circuit 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) Capacitor. (C) A charging/discharging control circuit connected to this capacitor and charging/discharging this capacitor with arbitrary charging current and discharging current. (d) A charge amount detection circuit that is connected to the capacitor and detects whether the capacitor has a predetermined amount of charge. (e) The capacitor is connected to the angular position detecting device, and when a first detection signal is generated in the angular position detecting device, the charge/discharge control circuit charges the capacitor, and the angular position detecting device is connected to the second detection signal. When the detection signal is generated, the capacitor is discharged by the charge/discharge control circuit, and an ignition signal is generated with the end of the discharge as the ignition timing. (f) connected to the charge amount detection circuit and the charge/discharge control circuit, and when the charge amount detection circuit detects that the charge amount of the capacitor is equal to or more than a predetermined amount, the charge current and the discharge current are A charge/discharge current reduction circuit that reduces the charge/discharge current by a predetermined ratio compared to when it is not above a predetermined amount.