JPS60116868A - Igniting apparatus for internal-combustion engine - Google Patents

Abstract

PURPOSE:To obtain an over-speed rotation preventing function with a simple apparatus, by detecting the speed of rotation of an internal combustion engine by use of the output of a pulse signal generating circuit provided for obtaining a control signal for an igniting apparatus, and thereby making it unnecessary to use a coil for detecting the speed or rotation. CONSTITUTION:The igniting apparatus of this invention comprises a pulse signal generating circuit 7 which produces pulse signals VP1, VP2 at rotational positions A1, A2 of an engine located respectively in the vicinity of the maximum ignition timing advancing position and the minimum ignition timing advancing position, and the pulse signals VP1, VP2 are applied to an ignition control signal generating circuit 8. The circuit 8 produces an ignition control signal Vb that is varied between the positions A1 and A2 with change of the engine speed, and an ignition control signal Vb' obtain from the signal Vb and an output signal Vq of an FF circuit 9 is applied to an igniting circuit 6. When the engine speed is raised to a predetermined value, the signal VP2 is produced while a rectangular wave is produced from a monostable multivibrator circuit 11 and the output Vq of the FF circuit 9 is reduced to zero to stop igniting operation.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an electronically controlled ignition device for an internal combustion engine that controls the ignition position by an electronic circuit.

BACKGROUND OF THE INVENTION Recently, in order to improve fuel efficiency, there has been a strong demand to reduce the weight of tIIJg, and it has also become necessary to accurately control the ignition position in accordance with the rotational speed. Therefore, recently, electronically controlled ignition devices, which are easy to reduce in size and weight and can accurately control the ignition position, have come into widespread use as ignition devices for internal combustion engines.

In this way, as modern internal combustion engines are becoming smaller and lighter, the engine is more likely to run at abnormally high speeds due to engine revving, which increases the risk of damage to the engine due to high-speed rotation. It is in. As a device to prevent engine overspeed, there is a device that detects the engine rotation speed and stops the ignition operation when the rotation speed exceeds a set value. In order to detect the rotational speed of the engine, a special detection coil was installed in the generator attached to the engine, which resulted in a large generator, which had the disadvantage of hindering weight reduction.

OBJECTS OF THE INVENTION An object of the present invention is to provide an ignition system for an internal combustion engine that can easily prevent engine overspeed by using a part of the circuit of an electronically controlled ignition system.

Structure of the Invention The present invention provides a current control semiconductor switch on the primary side of the ignition coil, and changes the primary current of the ignition coil by the operation of the semiconductor switch, thereby increasing the ignition voltage on the secondary side of the ignition coil. an ignition circuit that induces a voltage, and first and second pulses at first and second rotational positions set near the maximum advance position and the minimum advance position, respectively, of the ignition position of the internal combustion engine; a pulse signal generation circuit that generates a signal, and an ignition control signal whose generation position changes according to the rotational speed of ellQl between a minimum advance angle position and a maximum advance angle position by inputting the first and second pulse signals. An electronically controlled internal combustion engine ignition device is provided with an overspeed prevention function, the electronically controlled internal combustion engine ignition device comprising: an ignition i control signal generation circuit that generates an ignition i control signal, and the semiconductor switch is actuated by the ignition control signal to perform an ignition operation. In such an ignition device, the present invention provides a monostable ignition device that generates a rectangular wave signal with a constant time width triggered by one of the first and second pulse signals. a multivibrator, a flip-flop circuit, and a pulse signal when the other of the first and second pulse signals is generated while a rectangular wave signal is being generated from the monostable multivibrator; The flip-flop circuit is held in one stable state at the generation position of the monostable multivibrator, and when the other pulse signal is generated after the monostable multivibrator generates the rectangular wave signal, the flip-flop circuit is held in the other stable state. a flip-flop control circuit that controls the flip-flop circuit; and inputs the ignition control signal and the signal obtained from the flip-flop circuit, and supplies the ignition control signal to the semiconductor switch when the flip-flop circuit is in one stable state. a gate circuit that allows the ignition control signal to be supplied to the semiconductor switch when the flip-flop circuit is in the other stable state, and a gate circuit that allows the supply of the ignition control signal to the semiconductor switch; The time width is set to be approximately equal to the generation interval between the one pulse signal and the other pulse signal generated subsequently when the rotational speed of the IN leap reaches a set value.

In the above configuration, when the pulse signal generation circuit generates the first pulse signal at the first rotational position of the Il axis, the monostable multivibrator generates a rectangular wave signal. IIIa
If the rotation speed of I is less than the set value, the second pulse signal is generated during the time that the square wave signal is generated, and the flip-flop circuit is held in the "other stable state" because there is no second pulse signal. be done. Therefore, if the engine speed is below the set value,
The gating circuit allows the ignition l1ilI control signal to be applied to the solid state switch of the ignition circuit. The engine now ignites without any problems, and the tlIIIl rotates normally.

When the rotational speed of the engine exceeds the set value, a second pulse signal is generated while the monostable multivibrator is generating a rectangular wave, so a flip-flop is generated at the position where the other pulse signal is generated. The circuit is in a "one steady state" and the gating circuit prevents the ignition limit t11 signal from being applied to the ignition circuit's semiconductor switch. At this time, the ignition operation is blocked and the Bizen engine misfires, so the rotational speed of the tm jumper decreases.

When the rotational speed of the engine falls below the set value, the flip-flop circuit returns to the "other stable state" and the ignition operation resumes normally.

As described above, in the present invention, in order to detect the rotational speed using the output of the pulse signal generation circuit provided for obtaining the control signal of the ignition device, the coil for detecting the rotational speed is specially designed. There is no need to provide one, and a small semiconductor integrated circuit can be used for the monostable multivibrator and Noritsu flop circuit, so the ignition device can be provided with an overspeed prevention function without increasing the size of the device.

Example The present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 schematically shows the configuration of an embodiment of the present invention, in which 1 indicates a primary coil 1a and a secondary coil 1a.
2 is a battery as an ignition power source, and the battery 2 is connected between one end of the primary coil 1a and the ground with its negative electrode facing the ground side. , 3 is a transistor as a current control semiconductor switch, the emitter of which is grounded, and the collector connected to the other end of the primary coil 1a. One end of the secondary coil 1b of the ignition coil is connected to a non-ground terminal of a spark plug 4 attached to a cylinder of an engine (not shown), and the other end of the secondary coil is connected to the collector of a transistor 3. A protective capacitor 5 is connected between the collector of the transistor 3 and the ground, and a current interrupting type ignition circuit 6 is constituted by the above-mentioned parts. In this ignition circuit, an ignition control signal vb- is applied to the base of the transistor 3 at a position a predetermined angular phase ahead of the ignition position of the engine, and the transistor 3 is made conductive by this signal. Therefore, from battery 2 to primary coil 1
1 through the collector-emitter of transistor 3
Next current flows. Since the ignition control signal vb' disappears at the ignition position of tllllIl, the transistor 3 is cut off and the primary current is cut off. This causes a large magnetic flux change in the iron core of the ignition coil, and a 1% voltage for ignition is generated in the secondary coil 1b. Therefore, a spark is generated in the spark plug 4, and the engine is ignited. In this example, when a transistor is used as the current control semiconductor switch, the ignition control signal vb' becomes a rectangular wave signal, and its rising and falling positions become the conduction start position and the ignition position, respectively.

7 is the first rotational position A1 set near the maximum advance angle position of the engine ignition position and the return angle advance position! 1! This pulse signal generation circuit 7 generates the first and second pulse signals Vp1 and VCl2, respectively, at a second rotational position A2 set near f. and the signals S1 and V at the second rotational position, respectively.
A signal coil Ws whose output covers s2, and the signals VS1 and V
It consists of first and second pulse generation circuits 7A and 7B that shape the waveform of s2 and output first and second pulse signals Vpl and Vp2, respectively. The first and second pulse signals Vpl and VO2 are shown with respect to time t as shown in FIGS. 2A and 2B.

The first and second pulse signals V)1 and Vp2 are input to the ignition control signal generation circuit 8.

The ignition control signal generating circuit 8 outputs an ignition control signal (b) that changes between the first and second rotational positions in response to changes in the rotational speed of the engine. The ignition control signal VB obtained from this ignition control signal generation circuit 8 is combined with the signal VQ obtained at the negation output horn terminal of the flip-flip circuit 9.
- input to the AND circuit 10A forming the circuit 10, and the output of the AND circuit 10A is the transistor 3 of the ignition circuit 6;
A balance is supplied to the base (control+ terminal of the semiconductor switch) as a control signal vb'. Game (・Circuit 1
o prevents the supply of the ignition control signal vb to the spark control circuit 6 when the flip-flop circuit 9 is in one stable state and the signal VQ is at a low level, and when the flip-flop circuit 9 is in the other stable state. This allows the ignition control signal vb' to be supplied to the ignition circuit 6 when the signal VQ is at a high level.

The first pulse signal V obtained from the pulse signal generation circuit 7
rN is also input to the monostable multivibrator 11,
The multivibrator 11 has a first vibrator as shown in FIG.
At the generation position (time t1) of the pulse signal Vp1, a rectangular wave signal Vm having a constant time width τ is generated regardless of the rotational speed of the engine. The output J of the monostable multivibrator 11 is connected to the AND circuit 1 along with the second pulse signal Vp2.
2A, the output Va of the AND circuit 1.2A is input to the set terminal S of the flip-flop circuit 9, and the first pulse signal Vl)1 is input to the reset terminal r of the 7-rip 70-tub circuit 9. There is.

In this embodiment, the AND circuit 12A and the first pulse signal V
A circuit that supplies D1 to the reset terminal r of the 7-rip 70-tube circuit 9 generates the second pulse signal V while the rectangular wave signal Vm is being generated from the monostable multivibrator 11.
When D2 is generated, the 7-lip 70-tube circuit 9 is set in one stable state at the generation position of the second pulse signal, and after the monostable multivibrator 11 generates the rectangular wave signal Vm, the second pulse signal Vp2 is generated. A flip-flop control circuit 1 controls the flip-flop circuit 9 to maintain the flip-flop circuit 9 in the other stable state when
2 are configured. In the present invention, the time width τ of the rectangular wave signal Vm generated by the monostable multivibrator 11 is the first and Second pulse signal generation interval + t2-tl 1 (Fig. 2A,
(see B).

In the above embodiment, when the crankshaft of the engine is rotated by the starter, the pulse signal generation circuit 7 generates the first pulse signal Vp1 at tense t1 (first rotational position of the engine) as shown in FIG. 2A. do.

When this first pulse signal is generated, the monostable multivibrator 11 generates a rectangular wave signal Vrn as shown in FIG. 2C.
is generated, and the flip-flop circuit 9 is set (into the "other stable state") so that the signal V(1 becomes high level) as shown in FIG. 2E.

Further, the ignition control signal generating circuit 8 generates an ignition control signal vb as shown in FIG. 2F. When the rotational speed of the engine is less than the set value, the second pulse signal VD2 is not generated within the time period in which the rectangular wave signal Vl11 is generated, so the AND circuit 12A does not generate the output Va. Therefore, flip-flop circuit 9 is held in the "other stable state" and signal VQ is held at a high level. Therefore, when the rotational speed of the engine is below the set value, the gate circuit 10 allows the ignition control signal vb supplied from the ignition control signal generation circuit 8 to be supplied to the semiconductor switch of the ignition circuit, and the AND circuit 1
The output of 0Δ is supplied to the base of the transistor 3 of the ignition circuit 6 as the ignition control signal vb-. As a result, transistor 3 becomes conductive, and primary coil 1 of the ignition coil becomes conductive.
A current flows through a.

When the engine is running at low speed, the ignition control signal vb becomes zero around the time 12 when the second pulse signal Vp2 occurs (near the minimum advance position), and as a result, the transistor 3 of the ignition circuit is cut off and the ignition operation is disabled. will be held. In this manner, when the rotational speed of the engine is at the set speed, the ignition of the engine is performed without any problem, and vAIIl rotates normally.

As the rotational speed of the leapfrog increases, the ignition control signal vb
The position where the angle falls to zero advances toward the maximum advance angle position. When the rotational speed of the engine exceeds the set value, the second pulse signal Vp2 begins to be generated while the instep stable marubo pibrator 11 generates a rectangular wave, as shown in FIG. 3B and C. Therefore, as shown in the third diagram, the output va of the AND circuit 12A becomes high level at the position where the second pulse signal Vl)2 is generated. Therefore, the 7-rip, 70-tub circuit is set to "one stable state", and the flip-flop [
Since the output Vq of the I-tub circuit 9 becomes zero, the goo-I-circuit 10 prevents the ignition control signal vb- from being supplied to the semiconductor switch of the ignition circuit. At this time, the ignition operation is blocked and the RTM valve misfires, resulting in a decrease in the rotational speed of the engine.

III[When the rotational speed of I becomes less than the set value, the flip-flop circuit 9 returns to the "other stable state", so
Ignition operation will now occur normally.

FIG. 4 shows one embodiment of the configuration shown in FIG. 11, and the same components as in FIG. 1 are given the same reference numerals. In the embodiment shown in FIG. 4, the pulse signal generation circuit 7 includes transistors TRI and TR whose emitters are grounded.
2, resistors R1 and R2 connected between the collectors of transistors TR1 and TR2, and the positive output terminal F of a DC power supply (not shown), respectively, and transistor Tl? A diode D1 whose cathode is connected to the base of transistor TR2, a diode D2 whose anode is connected to the base of transistor TR2, a diode D3 whose cathode is connected to the base of transistor TR2 and whose node is grounded, and the base of transistor TR2. and a resistor R3 connected between the positive output terminal E of the power supply and the positive output terminal E of the power supply. Diode D1
The anode of the diode D2 and the cathode of the diode D2 are commonly connected to one end of the signal coil WS, and the other end of the signal coil is grounded. In this embodiment, the first pulse generating circuit 7A is configured by the transistor TR1, the diode D1, and the resistor R1, and the transistor TR2, the diode D2
, D3 and resistors R2 and R3 constitute a second pulse generating circuit 7B.

The signal coil Ws is connected to the rotation angle θ of the engine as shown in FIG. 6A.
, the first and second signals vS1 and VS2 are generated once per ignition cycle of the engine (IWJ period from when ignition is performed once to the next ignition in each cylinder). Here, the first signal @Vl, + and the second signal VS
2 is set to occur near the maximum advance angle position of the engine ignition position and near the minimum advance angle position 4=1, respectively.

In the above pulse signal generating circuit 7, when the signal coil WS is not generating a signal, the transistor TRI is in a cut-off state and the transistor TR2 is in a conductive state.

At this time, the potential at the collector of the transistor TR1 has risen to approximately the power supply voltage, and the potential at the collector of the transistor TR2 is approximately at the ground potential. The first signal VS1 reaches a predetermined threshold level vt (sixth
(see Figure A), the transistor TR1 becomes conductive and the collector potential of the transistor drops to approximately the ground potential.
When the first signal becomes below the threshold voltage level Vt, the transistors T and R1 are cut off and the potential at their collector rises to the power supply voltage again.

Therefore, the first pulse signal (pulse signal changing in the negative direction) Vpl as shown in FIG. 6B is obtained at the collector of the transistor TR1. The signal coil WS also generates a second signal VRI, which signal corresponds to a second rotational position 1ffA2.
When the voltage exceeds the threshold level vt, the i-transistor TR2 enters a cut-off state, and its collector potential rises to approximately the power supply voltage. When the second signal Vs2 falls below the threshold level, the transistor TR2 is cut off, and the potential of its collector drops to approximately the ground potential.

Therefore, a pulse signal Vp2 as shown in FIG. 6C is obtained at the collector of transistor 1-R2.

The monostable multivibrator 11 is a known one consisting of NAND circuits 11a and 11b, an inverter 11C, a capacitor 11d, and resistors 11e and 11f.The first pulse signal VD1 is input to one input terminal of the NAND circuit 11a. has been done. The output terminal of the NAND circuit 11a is connected to one input terminal of the NAND circuit 11b via a capacitor 11d and a resistor 11e.
A resistor 11f is connected between the connection point with 1e and ground. The output terminal of the NAND circuit 11b is connected to the input terminal of the inverter 11c, and the output of the inverter 911b is fed back to the other input terminal of the inverter 11a. The other input terminal of the NAND circuit 11b is connected to a positive output terminal E of a DC power supply (not shown).

Output rectangular wave signal v of the monostable multivibrator 11
m is input to one input terminal of the AND circuit 12A, and the second pulse signal Vp2 is input to the other input terminal of the AND circuit 12A.

The flip-flop circuit 9 is composed of a known circuit consisting of NOR circuits 9A and 9B and an inverter 9G. Pulse signal V
p1 is input respectively. The signal VQ applied to the negative logic output terminal 11 of the flip-flop circuit 9 is inputted to the AND circuit 10A together with the ignition control signal ■b.

In the above embodiment, when the rotational speed of the engine is lower than the set value, the second pulse signal Vp2 is generated after the stable multivibrator 11 generates the square wave signal ■m, so that the AND of the AND circuit 12A is Therefore, there is a signal at the set terminal of the flip-flop circuit 9! I can't get it.

After the rectangular wave signal Vm disappears and Iζ, the first pulse signal Vp1
When this occurs, the flip-flop circuit 9 is reset. At this time, the output Vq of the flip-flop circuit 9 becomes n level, so the AND of the AND circuit 10A is established, and the supply of the ignition signal Vb to the ignition circuit is permitted.

When the rotation speed of the IN leap exceeds the set value, the AND circuit 12 generates the second pulse signal Vp2 during the period when the monostable multivibrator 11 generates the rectangular wave signal vm.
The AND of A is established and a set signal is given to the Noritsu flop circuit 9. Therefore, the output signal Vq of the flip-flop circuit 9 becomes zero, thereby preventing the ignition control signal vb from being applied to the ignition circuit through the AND circuit 10A.

Next, referring to FIG. 5, a specific example of the configuration of the ignition control signal generation circuit 8 is shown. The ignition control signal generation circuit 8 shown in FIG. 5 includes first to third integration circuits 8A to 8.
C, integral operation control circuit 8D, and reference voltage generation circuit 8F.
, comparison circuits 8F and 8G, and a signal output circuit 8. Of these circuits, the first and second integration circuits 8A and 8B, the integral operation control circuit 8D, and the comparison circuit 8
F constitutes a conduction start position determining circuit that determines the position at which the primary current starts flowing through the ignition coil (the position at which the ignition control signal vb rises). Also, the third integrating circuit 8C
The ignition position (ignition 11111'm signal y
An ignition position determining circuit is configured to determine the falling position of the signal b. The signal output circuit 8 receives the output signals of the two decision circuits and the output of the integral operation control circuit 8D as input, and outputs an ignition control signal b which rises at a predetermined position and falls at the ignition position.

The integral operation control circuit 8D consists of a flip-flop circuit FF. Flip-flop circuit FF is NAND circuit N
1. The set terminal and reset terminal of the flip-flop circuit are connected to the collectors of transistors TRI and TR2 of the pulse signal generating circuit 7, respectively. This flip-flop circuit is set when the first pulse signal Vpl is input at the first rotational position [A1, and its positive logic output terminal Q goes to the n level, and its negative logic output terminal goes to the low level. Further, when the second pulse signal Vp2 is generated at the second rotational position @A2, the output terminal Q is reset and the positive logic output terminal Q becomes a low level. Furthermore, when the second pulse signal VD2 is applied at the second rotational position 11A2, it is reset and the positive logic output terminal Q
becomes low level, and the negative logic output terminal becomes high level. Therefore, the first rectangular wave signal @Vf1 and the second rectangular wave signal Vf2 are obtained at the positive logic output terminal Q and the negative logic output terminal of the flip-flop circuit FF, respectively, as shown in the sixth diagram and E.

The first integrating circuit 8A is a field effect transistor (hereinafter referred to as FE).
It's called T. ) Fl, and the source of the FET is connected to a resistor R6.
is connected to the gate of the FET via. , FET
The drain of Fl is connected to the positive output terminal E of the power supply, and a constant 11iF circuit 181 is constituted by the FET and resistor R6.

A first capacitor 4JC1 is connected between the gate and ground of FETFI. The non-grounded terminal of the first capacitor C1 is connected via a resistor R to the collector of a transistor TR3 whose emitter is grounded. transistor TR
The output terminal of 47 circuit OR1 is connected to the base of 3.
An inverter IN2 is connected to one input terminal of the OR circuit OR1.
A first pulse signal Vp1 obtained is inputted to the collector of the transistor TR1 of the pulse signal generation port M7 through the transistor TR1. In this embodiment, the transistor TR3 constitutes the reset switch S1.

The second integrating circuit 8B includes transistors TR5 and TR6,
! = FET F3 and resistor KR10 to filS20')3"
/dancer C2 and inverter IN3. The emitter of the transistor TR5 is connected to the output terminal F of the power supply, and the collector of the transistor is connected to the FET F
Connected to the drain of 3.

The source of FET F3 is connected to its gate via a resistor R10, and a second capacitor 1JC2 is connected between the gate of FET F3 and ground.

The collector of a transistor TR6 whose emitter is grounded is connected to the non-grounded terminal of the capacitor C2, and the base of the transistor TR6 is connected to the output terminal of the inverter IN3. Further, the base of the transistor TR5 is connected to the negative logic output terminal of the flip-flop circuit FF. The input terminal of the inverter IN3 is connected to the collector of the transistor TR1 of the pulse signal generation circuit. In this embodiment, transistors TR5 and TR6 constitute switches Sa and S2, respectively, and FETF3 and resistor R10 constitute a constant current circuit 1Satfi.

The voltage Vc1 obtained across the capacitor C1 of the first integrating circuit 8A is inputted to the comparator CP constituting the comparing circuit 8F via the resistor R12, and the voltage Vc2 across the capacitor C2 of the second integrating circuit 8B is It is input to the comparator CP via the resistor R13.

The third integrating circuit 8C for determining the ignition position is [ET F5
and the resistor R14 connected between the gate and source of the FET, the diode D4 whose 7 nodes are connected to the gates 1 to 1 of the FET F5, the capacitor C3 connected between the cathode of the diode and the ground, and the resistor R14 of the capacitor C3. F"ET F6 whose drain is connected to one end of the non-grounded side, and the FE
a resistor R15 connected between the source and gate of FET T, a transistor TR8 whose emitter is grounded and whose collector is connected to the gate of FET F6, a resistor R16 whose one end is connected to the base of transistor TR8, and a capacitor C3.
It consists of a transistor TR9 whose collector is connected to the non-grounded terminal of the transistor TR9 and whose emitter is grounded, and a resistor R17 whose one end is connected to the base of the transistor TR9.

The other end of the resistor R1G is connected to the positive logic output terminal of the 7-rip, 70-tube circuit FF, and the other end of the resistor R17 is connected to the collector of the transistor TR2 of the pulse signal generating circuit 7.

Further, the reference voltage generating circuit 8 E + is made up of a resistive voltage divider circuit consisting of a series circuit of resistors R+8 and R19 connected to the i DC power supply, so that a reference voltage Vr can be obtained across the resistor R19. This reference voltage Vr is the comparator circuit 8
The terminal voltage Vc3 of the capacitor C3 is input to the other input terminal of the comparator 8G through the resistor R20.

Signal output circuit 10G, i17'nd circuit IANI and AN
The conduction start position determination signal VO obtained from the comparator CP and the second rectangular wave signal Vf2 are input to the AND circuit AN1. Further, the ignition position determination signal v1 obtained from the comparator 93 and the first rectangular wave signal Vfl are input to the AND circuit AN2, and the output signal Vo' of the AND circuit ANI and the output signal vi° of the AND circuit AN2 are ORed. (input into circuit OR2).

The output signal ■i° of the AND circuit AN2 is also input to the OR circuit OR1 of the first integrating circuit 8A.

In the ignition control signal generation circuit 8 shown in FIG.
When the pulse signal Vp2 is applied, the transistor TR9 of the third integrating circuit 8C for determining the ignition position becomes conductive, so that the charge of the capacitor c3 is instantly discharged, and the terminal voltage of the capacitor becomes zero.

When the second pulse signal Vp2 disappears, the transistor TR
9 is cut off, content 1 and C3 are charged with a constant current through FET F5, resistor R14, and diode D4. Next, when the first rectangular wave value @vfi occurs at the first rotational position 11'fA1, the transistor TR8 becomes conductive, so that the capacitor C3 is discharged with a constant current through the FET F6, the resistor R15, and the transistor TR8. Therefore, the terminal voltage Vc3 of the ignition position determining capacitor C3 changes as shown in FIG. 6F with respect to the rotation angle θ. The period comparator 8G during which this voltage is higher than the reference voltage Vr is shown in Fig. 6G.
The ignition position M-state constant signal V1 is output as shown in FIG.

This signal Vi is input to the AND circuit AN2 together with the first rectangular wave signal Vfl, and the AND circuit AN2 receives the signal Vi and the rectangular wave signal Vf1 at the same time as shown in FIG.
A signal ■i° as shown in is output. The falling position @Ai of this signal vi° becomes the ignition position.

Further, when the first pulse signal Vpl is generated, a current is applied to the base of the 1-transistor TR3 of the first integrating circuit 8A, so that the transistor becomes conductive and discharges the capacitor C1. Since the base of the transistor TR3 is also given the signal @v1゛ via the OR circuit OR1, the transistor TR3 remains conductive while the signal ■1° is generated, and the terminal voltage of the capacitor C1 is Keep in Ecl. Here, ECI is as follows, assuming that the resistance value of resistor R is r:
It is given by EC+=rX11. Signal V at ignition position Ai
When 1° becomes zero, the transistor TR3 is cut off, so the capacitor c1 is charged with 1ml, and the terminal voltage of the capacitor C1 increases linearly.

Therefore, the terminal voltage VC+ of the first capacitor c1 changes as shown in FIG. 6I with respect to the rotation angle θ.

Further, in the second integrating circuit 8B, the transistor TR5 conducts when the base II current is applied while the negative logic output Vf2 of the flip-flop circuit FF is at a low level (ground potential), and the transistor TR5 conducts by the amount that the transistor TR5 conducts. A constant current I2 flows.

When the pulse signal generating circuit 7 generates the first pulse signal Vpl, the transistor 1R6 of the second integrating circuit 8B becomes conductive, so that the 71 load of the second capacitor c2 is instantly discharged. When the pulse signal Vp1 disappears, the transistor TR6
is cut off, and capacitor c2 is charged with current I2. When the second rectangular wave signal Vf2 is generated at the second position Δ2, the transistor TR5 is cut off, so the capacitor c
2 is stopped, and the terminal voltage of the capacitor C2 is kept constant. Therefore, the terminal voltage of capacitor C2 ■C2
The waveform of is shown in Figure 6 (■). The comparator CP generates the conduction start position determination signal 0 as shown in FIG. The signal vO° is output as shown in FIG. 6K during the period when the decision signal ①0 is generated simultaneously. The rising position of this signal vO° is the conduction start position A of the current control semiconductor switch.
It becomes O.

At the output terminal of the OR circuit OR1, an ignition control signal yb is obtained which rises at the conduction start position AO and falls at the ignition position At, as shown in FIG. This ignition control signal is supplied to the semiconductor switch of the ignition circuit as the ignition control signal vb-, and the primary current flows through the ignition coil at the rising edge of the ignition control signal yb-, and the semiconductor switch is cut off at the falling edge of the control signal. The ignition operation is performed.

In the example shown in FIG. 5, the residual voltage EC1 when the capacitor C1 is reset is obtained by inserting a resistor R into the discharge circuit of the first capacitor C1, but other constant voltage generating means, For example, this residual voltage Ec+ may be obtained using a Zener diode. The configuration of the ignition control signal generation circuit is not limited to the above example;
A signal (first and second pulse signal V
Any device that can generate an ignition control signal by inputting pl and Vp2) may be used.

FIG. 7 shows still another *embodiment embodying the configuration of FIG.
The input terminal of the inverter is connected so that the first pulse signal Vp1 can be obtained at the output side of the inverter. That is, in this embodiment, the first pulse signal VD1 is converted by the inverter IN3 into a positive pulse similar to the second pulse signal.

The monostable multivibrator 11 includes an operational amplifier 11Q, a transistor iih, and resistors 71i and 11j.

11, 11m and 11n, and a capacitor 11p. The resistors 11i and 11j are connected in series, and the series circuit of the resistors is connected between the output terminal of the inverter IN3 of the second pulse generating circuit 7B and the ground.
, 11J are connected to the base of the transistor 11h. The emitter of the transistor 11h is grounded, and the collector is connected to the negative input terminal of the operational amplifier 110. - A capacitor 11p is connected in parallel between the collector and emitter of the transistor 11h, and a resistor 11k is connected between the positive input horn terminal of the operational amplifier 110 and ground. Further, the collector of the transistor 11Q and the positive input terminal of the operational amplifier 11g are connected to the positive output terminal of the DC source Ii via resistors 11m and 11n, respectively. AND circuit 12A is inverter 12a
The input terminal of the inverter 12a is connected to the collector of the transistor TR2 of the second pulse signal generation circuit 7B. Resistor 12C is connected to the output terminal of inverter 12F3.
The base of the transistor 12b is connected through the transistor 12b, and one terminal of the transistor 12b is grounded. A resistor 12d is connected between the base of the transistor 12b and ground, and the collector of the transistor 12b is connected to the positive output terminal of the DC power supply via a resistor 1213. The output terminal of the operational amplifier of the monostable multivibrator 11 is connected to the collector of the transistor 12b.
The collector of 2b is connected to the set terminal S of the flip-flop circuit 9.

The flip-flop circuit 9 includes transistors 9a to 9C, a programmable unijunction transistor (hereinafter referred to as PUT) 9d, and resistors 9f to 9j. The emitters of the transistors 9a to 9C are grounded, and the base of the transistor 9a is connected to the output terminal of the inverter IN3 of the first pulse generating circuit via a resistor 9e. A resistor 9f is connected between the base of the transistor 9a and ground, and the collector of the transistor 9a is connected to a positive output terminal of a DC power supply (not shown) via a resistor 9Q. The base of transistor 9b is connected to the collector of transistor 12b of AND circuit 12A. The collector of transistor 9b is connected to the gate of PUT9d, and the anode of PLIT9d is connected to the collector of transistor 9a. A resistor 9h is connected between the gate anode of the PUT 9d, the cathode of the PUT is connected to the base of the transistor 9C via a resistor 91, and a resistor 9h is connected between the bases of the transistors 1 and 9C.
j is connected. Further, in this embodiment, the gate circuit 10 is constructed by directly connecting the collector of the transistor 9G to the output terminal of the ignition control signal generation circuit 8.

In the embodiment of FIG. 7, the monostable multivibrator 1
The capacitor 11D of No. 1 is charged to the polarity shown by a DC power supply (not shown). At this time, since the voltage between the negative input terminal of the operational amplifier 11g and the ground is higher than the voltage between the positive input terminal and the ground, the operational amplifier 1
The potential of the 1Q output terminal is at a low level. When the first pulse signal P1 is generated, the transistor 1ih becomes conductive and the capacitor 11p is discharged. Conden 4J11p
When is discharged, the output of the operational amplifier 11Q becomes level . When the capacitor 11D is charged through the resistor 11m and the voltage across the capacitor 11p becomes higher than the voltage across the resistor 11, the output of the operational amplifier 110 becomes Becomes a low level. Therefore, a rectangular wave signal vm whose time width is determined by the charging time constant of the capacitor 11p is obtained at the output terminal of the operational amplifier 11a.

In the flip-flop circuit 9, when the first pulse is not applied to the base (reset terminal) of the transistor 9a, the transistor 9b becomes ill! It is in state Ii. In this state, when the second pulse signal Vp2 is applied to the base (set terminal) of the transistor 9b, the transistor 9b
b becomes conductive and provides a gate signal to PUT9d. This causes PUT to pass and transistor 9C to conduct (setting the flip-flop circuit). transistor 9
When the first pulse signal VD1 is applied to the base of the transistor 9a, the transistor 9a becomes conductive, so the PUT 9d becomes cut off, and thereby the transistor 9G becomes cut off (
flip-flop circuit is reset).

In the AND circuit 12A, when the second pulse signal Vp2 is not input to the inverter 128, the output terminal of the inverter 12a is at a high potential. This prevents transistor 9b from becoming conductive. When the second pulse signal p2 is generated, the output terminal of the inverter 12a becomes low level, so the transistor 12b is cut off. At this time, if the output terminal of the operational amplifier 11Q is high level (rectangular wave signal If vm is not generated)
Transistor 9b becomes conductive, and flip-flop circuit 9 is set (transistor 9C becomes conductive).

In the embodiment shown in FIG.
If the second pulse signal Vp2 is generated after the output terminal of 1Q becomes the ground potential, the potential of the base of the transistor 9b is held at a low level (at the ground potential) after the rectangular wave signal m disappears. Therefore, even if the second pulse signal Vp2 is generated and the transistor 12b is turned off, the transistor 9b cannot be made conductive. At this time, the transistor 9c of the flip-flop circuit 9 is kept in a cut-off state, so that the ignition control signal is allowed to be supplied to the ignition circuit. When the rotational speed of the engine exceeds the set value, the second pulse signal Vp2 is generated while the rectangular wave signal Vm is being generated, and the transistor 12b is cut off. Therefore, the generation position of the second pulse signal is Flip-flop circuit 9
The transistor 9b1fi becomes conductive, and the PUT 9d becomes conductive. At this time, transistor 9G becomes conductive and blocks the supply of the ignition control signal to the ignition circuit.

FIG. 8 shows the basic configuration of another embodiment of the present invention. In this embodiment, the second pulse signal Vp2 is inputted to the monostable multivibrator 11 as an i~ trigger signal, and the monostable The multivibrator 11 generates a rectangular wave signal v with a constant time width τ when the second pulse signal Vp2 is generated.
Output m.

This rectangular wave signal vm is input to the AND circuit 12A together with the first pulse signal Vp1, and the output Va of the AND circuit 12A is input to the set terminal S of the flip-flop circuit 9. Reset terminal r of flip-flop circuit 9
The first pulse signal Vl is input to the input terminal. The rest of the structure is the same as the embodiment shown in FIG.

In the embodiment of FIG. 8, monostable multivibrator 1
The time width τ of the rectangular wave signal vm generated by 1 is equal to the second pulse signal Vp when the rotation speed of 1lVA reaches the set value.
It is set to be approximately equal to the difference 1t1-t2+ between the generation time t2 of the second pulse signal vm and the generation time t1 of the first pulse signal vm that occurs subsequently.

The signal waveforms of each part of the embodiment of FIG. 8 are as shown in FIGS. 9 and 10, and FIGS. 9 and 10 are respectively vIII
A case in which the rotation speed of I+ is less than the set value and a case in which it is greater than the set value are shown. In the embodiment shown in FIG. 8, when the rotation speed of the engine is less than the set value, as shown in FIG. 9C, after the rectangular wave signal vm generated at time t2 disappears, the pulse signal Vp1 of Since the occurrence occurs at t1, the AND of the one-AND circuit 12A does not hold, and as shown in Figure 9,
As such, its output ■a remains at a low level. Therefore 7
The lip 70 tube circuit 9 is not let. At this time, the output VQ of the flip 7O tube circuit 9 is maintained at a high level as shown in FIG. 9E, so that the ignition control signal vb is allowed to be supplied to the ignition circuit as shown in FIG. 9G. On the other hand, when the rotational speed of the engine exceeds the set value, as shown in FIGS. 10A and 10C, the first
Since the first pulse Vp1 is generated, the first pulse signal Vp
Simultaneously with the occurrence of l, the AND of the AND circuit 12A is established,
When the first pulse signal Vp1 is generated, its output voltage Va becomes high level. Therefore, at the generation position of the first pulse signal (time t1), the 7-lip, 70-tub circuit 9 is activated.
be done. This sets the flip-flop circuit 9! Therefore, the output signal Vq is at a low level (Fig. 10E).
), and the AND of the AND circuit 10A no longer holds true. At this time, as shown in FIG. 10G, the supply of the ignition 1bllllll signal to the ignition circuit is blocked.

FIG. 11 shows an embodiment embodying the configuration shown in FIG. 8. In this embodiment, the first
The input terminal of the inverter IN3 is connected to the collector of the transistor of the pulse generating circuit 7A of the inverter IN3.
One end of a capacitor C4 is connected to the output J terminal of No.3. A resistor R21 is connected between the other end of the capacitor C4 and the ground, so that the first pulse signal Vpl is obtained at the connection point between the capacitor C4 and the resistor R21. That is, in this embodiment as well, the first pulse signal VD1 is converted by the inverter IN3 into a positive pulse similar to the second pulse. Moreover, the monostable multivibrator 11 is A
A circuit 11q, 11r, capacitor 11d, and resistor 11e
and 11f, and the flip-flop circuit 9 is a NOR circuit 9A.

Consists of 9B.

FIG. 12 shows yet another embodiment that embodies the configuration of FIG. 8, and in this embodiment, the pulse signal generating circuit 7 is constructed in the same manner as the embodiment of FIG. 11. Also, a flip-flop circuit 9, a gate circuit 10. The monostable multivibrator 11 and the AND circuit 12A are constructed similarly to the example shown in FIG.

13 to 21 show the flip-flop control circuit 12.
This figure shows still other embodiments of the present invention having different configurations, and in these embodiments, the flip-flop control circuit 1
2 consists of an AND circuit 12A, an inverter 12B, and an AND circuit 12C. FIG. 13 shows a case where the monostable multi-by-break 11 is triggered by the first pulse signal VD1 as in the embodiment of FIG. 1, and in this embodiment,
The output of the monostable multivibrator 11 is connected to the inverter 12
The output (e) of the inverter 12B is input to the AND circuit 12G together with the second pulse signal VD2. In other respects, the structure is exactly the same as that in FIG.

In the embodiment shown in FIG. 13, the operation when the rotational speed of the engine is less than the set value is as shown in the signal waveform diagram of FIG. 14. That is, when the rotation speed of tIll is less than the set value, the second pulse signal VD2 is generated after the rectangular wave signal ■m disappears, so the output Va of the AND circuit 12A is low as shown in Figure 14. It remains at the level, and the flip-flop circuit 9 is not set. In this state, when the flip-flop circuit 9 is reset by the second pulse signal VD2 as shown in FIG. Allows supply of ignition control signal yb to the circuit.

Also, when the rotational speed of tIIIl exceeds the set value, the first
As shown in FIGS. 5B and 5C, the second pulse signal Vp2 is generated while the rectangular wave signal ym is being generated.
As shown in the figure, the AND of the AND circuit 12A is established at the position where the second pulse signal is generated, and the output Va of the AND circuit 12A becomes high level. Therefore, the flip 70 and pull circuit 9 are set at the position where this second pulse signal is generated.
The output Vq of the flip-flop circuit 9 becomes low level.

At this time, the AND circuit 10A blocks the supply of the ignition control signal yb to the ignition circuit.

FIG. 16 shows an embodiment in which the configuration of FIG. 13 is made concrete. In this embodiment, the pulse signal generation circuit 7
, the flip-flop circuit 9, the gate circuit 10, and the monostable multivibrator 11 are constructed similarly to the embodiment shown in FIG.

FIG. 17 shows still another embodiment of the embodiment shown in FIG. The configuration is similar to that of the example, but in this example, the output terminal of the counterfeit amplifier 11Q of the monostable multivibrator 11 is connected to the positive output terminal of a DC power supply (not shown) via a resistor 11s. Further, a resistor 9k is connected between the base and emitter of the transistor 9b of the flip-flop circuit 9, and the base of the transistor 9b is connected to the output terminal of the AND circuit 12A via a resistor 9m.

Figure 18 shows the monostable multivibrator 1 as in Figure 8.
1 is triggered by the second pulse signal Vp2, and in this embodiment, 7 rip 70
The fall road control circuit 12 is configured similarly to the example shown in FIG. 13.

In the embodiment of FIG. 18, the signal waveforms of each part when the engine rotational speed is less than the set value and when it is greater than or equal to the set value are as shown in FIGS. 19 and 20, respectively, and the second pulse signal Vp2 At the point where the monostable multi-pie break 11 is triggered by 1 except that
The same operation as in the embodiment shown in FIG. 3 is performed.

FIG. 21 shows an embodiment in which the configuration of FIG. 18 is further embodied, and in this embodiment, the pulse signal generation circuit 7
is constructed similarly to the embodiment shown in FIG. 7, and the flip-flop circuit 9 and monostable multivibrator 11 are constructed similarly to the embodiment shown in FIG.

In the above explanation, a current interrupt type circuit is used as an example of the ignition circuit, but when an ignition circuit such as a capacitor discharge type ignition circuit is used, which controls the primary current of the ignition coil using a semiconductor switch to perform the ignition operation. The present invention can be widely applied to.

Effects of the Invention As described above, according to the present invention, since the rotation speed is detected using the output of the pulse signal generation circuit provided for obtaining the control signal of the ignition device, the rotation speed is detected. There is no need to install a special coil for the ignition system, and a small semiconductor integrated circuit can be used for the monostable multivibrator and flip-flop circuit, so the ignition system can be provided with an overspeed prevention function without increasing the size of the device. There is an advantage that it can be done.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the basic configuration of an embodiment of the present invention, and FIGS. 2 and 3 are diagrams of FIG. A diagram showing the signal waveforms of each part, Fig. 4 is a circuit diagram showing an embodiment embodying the configuration of Fig. 1, and Fig. 5 is a circuit showing a specific example of the configuration of the ignition control signal generation circuit. 6 is a diagram showing the signal waveform of the platform in FIG. 5, FIG. 7 is a circuit diagram showing an embodiment embodying the configuration of FIG. 5, and FIG. 8 is a diagram showing a further embodiment of the present invention. Block diagrams showing other embodiments, FIGS. 9 and 10
The figures are diagrams showing the signal waveforms of each part in Fig. 8 when the engine rotational speed is less than the set value and when it is greater than the set value, respectively, and Figs. 11 and 12 respectively illustrate the configuration of Fig. 8. FIG. 13 is a block diagram showing still another embodiment of the present invention, and FIGS. 14 and 15 show the case where the engine rotational speed is less than the set value and the set value, respectively. Fig. 16 and 17 are circuit diagrams showing different embodiments embodying the configuration of Fig. 13, respectively.
The figure is a block diagram showing still another embodiment of the present invention.
Figures 9 and 20 are scaled diagrams showing the signal waveforms of each part in Figure 18 when the rotational speed of IIl[l is less than the set value and above the set value, respectively, and Figure 21 shows the configuration of Figure 18. FIG. 2 is a circuit diagram showing a concrete example. 1...Ignition coil, 2...Battery, 3...1-
Ransistor, 4...Spark plug, 7...Pulse signal generation circuit, 8...Ignition control signal generation circuit, 9...Fritsubuf 1" tube circuit, 9A, 9B...Nor circuit, 9
C... Inverter, 9a, 9b, 9G-transistor, 9 d-1) UT, 9e to 9, 9m-... Resistor,
-10...Goo 1~circuit, 11...monostable multivibrator, 11a. 11b... NAND circuit, 11G... Inverter, 1
1d... Capacitor, 11e, 11f... Resistor, 1
1g...Operation amplifier, 11h...Transistor, 1
11゜11j, 11, 11m, 11n...Resistance, 1
1q. 11r...OR circuit, 11S...resistance, 12...
Flip-flop circuit control circuit, 12A, 12C...
AND circuit, 12B...inverter. Figure 21

Claims (1)

[Claims] An ignition circuit that includes a current control semiconductor switch on the primary side of the ignition coil and changes the primary current of the ignition coil by operating the semiconductor switch to induce a high voltage for ignition on the secondary side of the ignition coil. and a first rotation position and a second rotation position respectively set near the maximum advance angle position and the minimum advance angle position of the ignition position of internal combustion tUt+.
and a pulse signal generation circuit that generates a second pulse signal; and a pulse signal generation circuit that receives the first and second pulse signals and adjusts the generation position between a minimum advance angle position and a maximum advance angle position according to the rotational speed of the engine. an ignition control signal generation circuit that generates a variable ignition control signal, the ignition device for an internal combustion engine comprising: an ignition control signal generation circuit that operates the semiconductor switch according to the ignition control signal to perform an ignition operation; a monostable multivibrator that generates a rectangular wave signal of a constant time width when triggered by one of the pulse signals of the above; a flip-flop circuit; When the other pulse signal of the first and second pulse signals is generated, the flip-flop circuit is set to one stable state at the generation position of the other pulse signal, and the monostable multivibrator generates a rectangular wave signal. a flip-flop control circuit that controls the flip-flop circuit so as to maintain the flip-flop circuit in the other stable state when the other pulse signal is generated after the ignition control signal and the flip-flop circuit are generated; When the flip-flop circuit is in one stable state, the ignition control signal is blocked from being supplied to the semiconductor switch, and when the flip-flop circuit is in the other stable state, the ignition control signal is input to the semiconductor switch. and a gate circuit that allows the supply of the ignition control signal, and the time width of the rectangular wave signal generated by the monostable multivibrator is lII! 1. An ignition device for an internal combustion engine, wherein the ignition device is set to be approximately equal to the generation interval between the one pulse signal (fi) and the other pulse signal generated subsequently when the rotational speed of the first pulse signal reaches a set value.