JPS59170467A - Ignition apparatus for internal combustion engine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention comprises an ignition coil whose primary winding together with an electronic interrupter forms a series circuit connectable to a power source; and a second threshold switch, the inputs of which are connected in parallel to one common alternator, and in which the interrupter is in a conducting state in the switched-in state of these threshold switches. The double-opening value switch is controlled by an AC voltage signal supplied from an alternator, and the curved part of the waveform before reaching the peak value of the waveform of this AC voltage signal is used for switching in the threshold switch. and the part of the waveform curve after this peak value is used to switch off the threshold switch, in which case normally the switching control of the electronic interrupter to the cut-off state is carried out by the first threshold switch. If this switching control is not carried out, the interrupter is rendered non-conducting by a second threshold switch connected to a timing element, and the switch-in and switch-on values of the first threshold switch are have mutually opposite polarities with respect to the zero value of the alternating voltage signal, while the polarity of the switch-in value and the switch-off value of the second threshold switch is identical to the polarity of the switch-in value of the first threshold switch, The present invention relates to an ignition device for an internal combustion engine.

An ignition device of this type has already been proposed (in German Patent Application No. P32L5728.2). However, this known ignition device has the following drawbacks. That is, a disturbance Q-rus that occurs when the ignition system is switched on and the internal combustion engine is not activated can initiate any number of ignition processes, leading to a failure of the ignition system.

Effects of the Invention In the ignition device according to the present invention, claim 1
By using an arrangement with the features described in section 1, the above-mentioned drawbacks are avoided.

Description of examples Next, embodiments of the present invention will be described in detail using the drawings.

The ignition device shown in FIG. 1 is for an internal combustion engine, also not shown, of a motor vehicle. may be an automobile's power supply.A conductor 2 connected to the ground comes out from the negative terminal of the DC power supply 1, and a power supply line 4 including an operating switch (ignition switch) 3 comes out from the positive terminal. This feeder line 4 runs through the primary winding 5 of the ignition coil 6 to the collector of the npn (npn) transistor, and from the emitter of the transistor 7,
This is the starting point of the circuit branch connected to the ground wire 2. The emitter-collector of the transistor 7 forms an electronic interrupter 8 in this embodiment of the invention.

One end of the secondary winding 9 belonging to the ignition coil 6 is connected to the primary winding 5
The other end of the secondary winding 9 is connected to the ground wire 2 via a spark plug 10.

Furthermore, the feeder line 4 is the starting point of a circuit branch that leads via a current limiting resistor 11 to the anode of a polarity protection diode 12 . The cathode of the wrong polarity connection protection diode 12 is connected to the connection point 13. The connection point 13 is connected to the ground wire 2 via a buffer capacitor 14.

Buffer capacitor 4 has a Zener diode 1 in its shunt.
]5. The anode of the Zener diode 15 is connected to the ground line 2.

This ignition device has a first threshold switch J6 and a second threshold switch 17. In this case, the first threshold switch 6 is constituted by an operational amplifier 18, and the second threshold switch 17 is constituted by an operational amplifier 19. The input sides of these two operational amplifiers 18, 1.9 are connected in parallel. That is, the inverting input side of the operational amplifier 18 is connected to the inverting input side of the operational amplifier 19 via the connection line 20, and the non-inverting input side of the operational amplifier 18 is connected to the inverting input side of the operational amplifier 9 via the connection line 21. Connected to the non-inverting input side.

A small alternator 22 is used as a signal generator. One connecting terminal 23 of this alternating current generator 22 is connected to the connecting line 20 , and the other connecting terminal 24 of the alternating current generator 22 is connected to the connecting line 21 .

The inverting input side of the operational amplifier 18 is connected to the ground line 2 via the resistor 25, and the non-inverting input side of the operational amplifier 18 is connected to the ground line 2 via the resistor 25.
It is connected to its output side via a positive feedback resistor 26.

On the other hand, the inverting input side of the operational amplifier 19 is connected to the connection point 13 via a resistor 27, and the non-inverting input 11111 of the operational amplifier 19 is connected to its output side via a positive feedback resistor 28.

threshold switch ], 5 , ], 7 and electronic interrupter 8
A logic coupling circuit 29 is connected between the transistor 7 forming the
is connected. This logic coupling circuit 29 is surrounded by a dashed line in the figure, and is supplied with current from the connection point 3 through a connection line 30 and from the ground line 2 through a connection line 31. This logical combination circuit 29 is connected to a timing element 32. This timing element 32 is advantageously constituted by a monostable multi-pie break 33.

The input side of the monostable multi-ζ isolator 33 is connected to the output side of the operational amplifier 19 and the input side of the AND element 34. The other input side of the AND element 34 is connected to the negative output side of the monostable multinomial ibrator 33 and the clock input side T of the flip-flop 36 . The output side of the AND element 34 is connected to the input side of another AND element 370. This AND element 37 then also has one negative input. This negative input side is connected to the cutting edge side of the operational amplifier 18. moreover,
The output side of the operational amplifier 18 is connected to the input side R of the flip-flop 38 and to one input side of the OR element 39 . The other input side of the OR element 39 is the flip-flop 3
It is connected to the output side Q of 6. flip flop 36
The input side of has the potential of the ground wire 2. The static input S of the flip-flop 36 is connected to the output Q of the flip-flop 38. The input side S of the flip-flop 38 is connected to the output side of the AND element 37.

o From the output side of the R element 39, the connection line is npn t'
It extends to the base of Leper transistor 41. The emitter of this npn driver transistor 41 is connected to ground #! The collector of the npn driver transistor 41 is connected to the base of the transistor 70, and is also connected to the connection point 13 via the resistor 12.

The ignition system described above operates as follows. FIG. 2 shows the voltage (U) over time (11) The diagram shows the alternating voltage signal Ua supplied by the alternator 22, i.e. the switch-in value of the first threshold switch 16. Ub and 2nd
switch-in value U of the threshold switch 17. have at least approximately the same value and have the same polarity, ie, positive polarity, with respect to the zero value O of the AC voltage signal Ua. Therefore, the waveform curve portion Ue before reaching the peak value Ud is used for switching in the threshold switch 16, 17, and the curve portion Uf after reaching the peak value Ud is used for the threshold switch 16.
6.17 is used for switching off. that time,
The switch-off value Ug of the first threshold switch 16 has a polarity opposite to the switch-in value Ub of the threshold switch ] 6 with respect to the zero value O of the alternating voltage signal Ua, i.e. has a negative polarity in the embodiment of the invention. shall have. Further, the switch-on value Uh of the second threshold switch 17 is determined with respect to the zero value 0 of the AC voltage signal Ua.
Switch-in value U of 7. , i.e., in the embodiment according to the invention, positive polarity.

Resistors 25, 26, 27.28 have a switching hysteresis IJ b-[1g and U in the voltage one-hour magnetogram shown in FIG. -Uh and their values.

The AC' voltage signal U8 supplied from the alternator 22 is
first threshold switch] 6 switch-in threshold Ub and the second
The switch-in threshold U of the threshold switch 17. , these threshold switches 16,17 are switched on. That is, from their output side, a potential equal to the ground potential appears. As a result, the O signal is supplied to the output side of the OR element 39. This O signal strip controls the emitter-collector of transistor 11 to be cut off, and controls the emitter-collector of transistor 7 to be conductive. As a result, a current flows through the primary winding 5 and energy is stored in the ignition coil 6 for the next ignition process. The AC' voltage signal Ua is
Q) Switch-off of threshold switch 17 When falling below threshold Uh, this threshold switch 17 is switched off and a positive voltage appears at its output j.

The timing element 32 is thereby set, so that the O signal appears at the inverting output of the timing element 320. Therefore, the l signal is supplied to the input side of the AND element 34 connected to the threshold value switch 17, and the l signal is supplied to the input side of the AND element 34, which is connected to the threshold value switch 17.
The input connected to the output of 2 is supplied with the O signal.

Therefore, the O signal is sent out from the output side of the AND element 34. Therefore, the O signal continues to act on the output side of the AND element 37, the output side Q1 of the solver tube 38, and the output side Q of the solver tube 36, and the OR element 39
The state of is not changed by the output of the output Q of the flip-flop 36.

When the internal combustion engine operates normally, the AC' voltage signal Ua is
It changes below the switch-off threshold Ug of the first threshold switch 16. As a result, the first threshold switch 16
The l signal appearing on the output side of is supplied to the base of transistor 410 via OR element 39, and
The emitter-collector of transistor 7 is controlled to be conductive, while the emitter-collector of transistor 7 is controlled to be cut off. As a result, the current flowing through the primary winding 5 is interrupted, and a high voltage/ξ pulse is generated in the secondary winding 9. This high voltage ξrus is applied to the ignition ZORAG 10 as
Generates ξ-ri (ignition spark).

In the normal case, at time t2, the instability time of timing element 32, which was set at time tl, has elapsed. That is,
A signal is applied to the two inputs of the AND element 34, and therefore a signal appears at the output of the AND element 34. However, this "l" signal is not transmitted through the AND element 37.

This is because the 0 signal remains applied to the other input side of the AND element 37.

The trailing edge of the pulse occurring in the timing element 32 also acts on the clock input T of the solid block 36. However, this solid tube 36 produces only a 0 signal at its output Q. Therefore, the states of transistors 41 and 7 do not change.

Internal combustion engine stops due to overload, AC voltage signal Ua
has not yet reached the switch-off value U3 of the first threshold switch 16, 1 is applied to the input side of the AND element 370.
A signal appears. As a result, at time t2, this A
Output side of ND element 37, output 9 of flip-flop 38
111 Q and a 1 signal is applied to the input side S of the flip-flop 360. Based on this, this I signal also appears at the output Q of the flip-flop 36. This l signal reaches the base of transistor 410 via OR element 39. As a result, the emitter-collector of this transistor 41 becomes conductive, while the emitter-collector of the transistor 7, which constitutes the electronic interrupter 8, becomes non-conductive.
An ignition spark is generated by the spark plug IOK.

The above-mentioned disconnection state in the electronic interrupter 8 is maintained in the switched-on ignition system, even if the internal combustion engine is not started again. As a result, no current flows through the primary winding for an unacceptably long period and the ignition coil 6 is not damaged by overheating.

(1' Patent Application No. P32 of the Federal Republic of Italy] 5728.2
element 36, as in the case of the ignition device described in
If the output side of the AND element 34 is directly connected to the input side of the OR element 390 without using 37. If not, a disturbance ξrus Ui as shown in FIG. 3 will trigger arbitrarily large numbers of ignition processes. When using the logical combination circuit 29 according to the invention, each of these faults U1 causes the threshold switch 17 to be switched in and subsequently the timing element 32 to be set. However, based on that, the ?? supplied from the timing element 32? If the trailing edge of the loop reaches the clock input T of the flip-flop 36, the flip-flop 36 always
1 signal is applied only to the output side Q of the transistor 41 and the base of the transistor 41. This 1 signal then maintains conduction between the emitter and collector of transistor 41 and thus maintains electronic interrupter 8 in a disconnected condition. Such obstacles/
The relay Ui therefore has no influence on the electronic interrupter 8. The above-mentioned state ends only when the alternating voltage signal Ua reaches the threshold value U3 of the first threshold switch 16. Furthermore, at this time, an O signal appears on the inverting input side of the amplifier 370, and a 1 signal appears on the input side R of the flip-flop 38. Based on this, the flip-flop;
″38 output side.

supplies the O signal to the input S of the flip-flop 36;
A 0 signal at its input is supplied to the output Q14 of the flip-flop 36 each time a signal is supplied to the clock input T. In normal operation, the output Q of the flip-flop 36 therefore has no influence on the transistor 41 and thus on the electronic interrupter 8.

[Brief explanation of drawings]

FIG. 1 is a schematic circuit diagram of an ignition device according to the invention, and FIGS. 2 and 3 are diagrams for explaining the operation of the ignition device according to the invention. 5...Primary winding, 8...Electronic interrupter, ], 6,
], 7... Threshold switch, 22... AC generator, 2
9... Logic coupling circuit, 32... Timing element, 34.3
7...AND, J child, 36, 38.79 Noah"
70 f, 3...OR element-40:

Claims (1)

Claims: 1. An ignition coil, the primary winding of which, together with an electronic interrupter, forms a series circuit connectable to a power source, and first and second threshold switches; The double-open value switch is such that its input side is connected in parallel to a common alternator, and in the switched-in state of the double-open value switch, the interrupter is in a conductive state, and the double-open value switch The value switch is controlled by an alternating current voltage signal supplied from an alternating current generator, and the waveform curve portion of the alternating voltage signal waveform before reaching the peak value is used for switching in the threshold switch. The part of the waveform curve after the high value is used to switch off the threshold switch,
In this case, in the normal case, the switching control of the electronic interrupter to the cut-off state is carried out by means of a first threshold switch; if this switching control does not take place, the interrupter is switched to the cut-off state, rendered non-conductive by a threshold switch of 2;
Furthermore, the switch-in value and the switch-on value of the first threshold switch have mutually opposite polarities with respect to the zero value of the alternating voltage signal, and the polarity of the switch-in value and the switch-off value of the other second threshold switch , the polarity of the switch-in value of the first threshold switch is the same as the polarity of the switch-in value of the first threshold switch. , and a second threshold switch (1) connected to the timing element (32).
7) turns off the electronic interrupter (8), the logical coupling circuit (29) switches the first threshold switch (]6)
An ignition device for an internal combustion engine, characterized in that the interrupter (8) is maintained in the disconnected state until the interrupter (8) is supplied with a signal (Ug) to disconnect the interrupter (8). 2 The logic combination circuit (29) is connected to two threshold switches (1
6, 17) and the output 111 of the timing element (32)
11 K-connected ignition device according to claim 1. 3. The logical combination circuit (29) has a clocked flip-flop (36), and for clock control,
The trailing edge of the ξ rus (
Uh), the ignition device according to claims 1 and 2.