JPH0472993B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Related Field of the Invention The present invention relates to an electric current source, the primary winding of which, together with an electronic interrupter, forms a series circuit connectable to a current source; An ignition control method for an internal combustion engine, the method comprising: an ignition coil operatively connected to an ignition coil; a device for extracting a value corresponding to the rotational speed from between the primary winding and the electronic interrupter; and a rotational speed limiting circuit. The present invention relates to an ignition control device for implementing.

An ignition device of this type is already known (from German Patent Application No. 1673365). However, in this known device, a conventional speed limitation (i.e. as known for example from German Patent No. 1906883) does not result in a steady build-up of the ignition voltage in the case of speed limitation. Alternatively, the ignition voltage itself is not generated, so that a value corresponding to the actual rotational speed cannot be extracted between the primary winding and the electronic interrupter.

Problem to be Solved by the Invention An object of the present invention is to provide a configuration that allows a value corresponding to the engine speed to be extracted even when the engine speed reaches the maximum allowable speed and the engine speed is restricted. be.

Means for Solving the Problems The above problem has been solved by the present invention, in which the induced voltage generated in the ignition coil when the electronic interrupter is cut off when the maximum allowable rotation speed is reached, forms a value corresponding to the rotation speed. The problem is solved by first increasing the spark plug to a value necessary for the spark plug, and then lowering it to a value that prevents the spark plug from generating an electric spark.

Further, the device of the present invention is provided with an electronic switch, a protection circuit, an element for reducing the induced voltage generated in the ignition coil, and a rotation speed monitoring device, and an element for reducing the induced voltage. is connected to the primary winding of the ignition coil, said electronic switch is connected to a speed monitoring device and a protection circuit, and when the maximum permissible speed is reached, said electronic switch is activated by the speed monitoring device. When the electronic switch is brought into a state in which conduction can be controlled, and when the induced voltage generated in the ignition coil reaches a predetermined value when the electronic interrupter is cut off, the protective circuit switches the electronic switch to a conductive state, and the electronic switch becomes conductive. According to
A limited control current is conducted to the electronic interrupter through an element for reducing induced voltage;
The induced voltage generated in the ignition coil is configured to be reduced to a value at which no electric spark can be generated in the ignition plug.

DESCRIPTION OF EMBODIMENTS Next, embodiments of the present invention will be described in detail with reference to the drawings.

The ignition device shown in the circuit diagram in FIG. 1 is for an internal combustion engine, also not shown, of a motor vehicle, not shown. This ignition device is powered by a DC power supply 1. This DC power source 1 can be a battery of an automobile. A line 2 connected to earth comes out from the negative pole of the power source 1, and a feeder line 4 including an actuation switch (ignition switch) 3 comes out from the positive pole of the power source 1. The feeder line 4 first connects the primary winding 5 of the ignition coil 6.
, then through the electronic interrupter 7 to the ground wire 2
This is the starting point for the circuit branch that leads to . Electronic interrupter 7
is formed between the emitter and collector of the npn transistor 8. A secondary winding 9 of the ignition coil 6 is connected to the ground wire 2 via a spark plug 10. From the connecting line provided between the primary winding 5 and the electronic interrupter 7, the rotational speed of the internal combustion engine is supplied to the device 11, which corresponds to the rotational speed to the indicating device 12 in the preferred embodiment. The value is retrieved by tapping. The transistor 8 is provided with a protection circuit 13 for protection from overvoltage. This protection circuit 13 includes voltage dividers 14 and 15 connected to a shunt between the emitter and collector of the transistor 8, and tap 1 of the voltage dividers 14 and 15.
6 and a switch element 17 connected between the base of the transistor 8 and the switch element 17 having a predetermined breakdown voltage. This switching element 17 is preferably a Zener diode 17'.

Furthermore, the power supply line 4 is connected to a misconnection protection diode 1.
Current limiting resistor 1 is connected between the anode and cathode of 8.
9 to the connection point 20 and from there to the ground line 2 via the buffer capacitor 21. A Zener diode 22 is connected in parallel to the buffer capacitor 21. This Zener diode 22 is connected to the connection point 20
The anode is used to stabilize the potential of the ground wire.

From the connection point 20, a connection line is connected to a control device 23, which is known per se. This control device allows current to flow through the primary winding 5 before each ignition process over a relatively wide speed range. Devices of this type are known, for example, from the Federal Republic of Germany patent no.
It is constructed as described in US Pat. No. 2,244,781. Furthermore, this control device 23
, and its input side is connected to a signal transmitter 24, one side of which is connected to ground potential. The signal transmitter 24 is constructed in the form of a small alternator. In this case, when the signal transmitter 24 is connected to the control device 23, the electronic interrupter 7 is placed in a current conducting state during a pulse duration t1 and in a current-conducting state during a pulse duration t2. For this purpose, the output of the control device is connected to the base of the npn transistor 25. The emitter of transistor 25 is connected to ground wire 2
The collector is connected to the connection point 20 via a resistor 26. Furthermore, a connection line comes out from the collector of the transistor 25. This connection line is connected to the anode of the blocking diode 27, and further from the cathode of the blocking diode 27.
It extends to the base of a transistor 8 forming an electronic interrupter 7.

Furthermore, this ignition device is provided with a rotational speed limiting circuit 28. This rotation speed limiting circuit 28 includes:
A monitoring device 29 for the rotational speed of the internal combustion engine is included. This rotation speed monitoring device 29 is connected to a connection point 20
and the ground wire 2, and its output side is connected to the control terminal 30. Furthermore, the rotation speed limiting circuit 28 has an electronic switch 31. This electronic switch 31 is constructed between the emitter and collector of an npn transistor 32. The emitter of the transistor 32 is connected to the ground line 2, and the collector thereof is connected to the connection point 20 via a resistor 33. The base of the transistor 32 is connected to the control terminal 30 and to the ground line 2 via a resistor 34. At that time, the connection terminal 30 is further connected to the npn transistor 35
connected to the collector. transistor 35
The emitter is connected to the ground line 2, and the base is connected to the collector of the transistor 25 via a resistor 36. The emitter and collector of a transistor 32 constituting the electronic switch 31 are connected in parallel to the base and emitter of a transistor 37. The transistor 37 is of the npn type, and its emitter is similarly connected to the ground line 2. At that time, the emitter of transistor 37
Between the collectors is the primary winding 5 of the voltage divider 14, 15.
The collector of the transistor 37 is further connected to the base of the transistor 32 via a feedback resistor 38. Furthermore, voltage dividers 14, 15
The tap 16 is connected to the cathode of a Zener diode 40 via a resistor 39. The anode of the Zener diode 40 is connected to the transistor 3.
Connected to the base of 2.

The ignition system described above operates as follows.

When the actuation switch 3 is closed, the device:
It becomes ready for operation. In the control device 23, the period
When t1 begins, the emitter of transistor 25
The connection between the collectors is cut off, and the emitter-collector of the transistor 8 constituting the electronic interrupter 7 is turned on. A current therefore flows through the primary winding 5, with the result that ignition energy is stored in the ignition coil 6 for the next ignition process.

When the period t2 starts in the control device 23, the emitter-collector of the transistor 25 is controlled to be in a conductive state, and the emitter-collector of the transistor 8 constituting the electronic interrupter 7 is controlled to be in a cut-off state. Thereafter, an induced voltage is generated in the ignition coil 6. This induced voltage is supplied as a high voltage pulse to the spark plug 10, where it is used to generate an electric spark. At the same time, this induced voltage pulse is used as rotation speed information in the device 11.

In order to suppress the generation of ignition sparks when the maximum permissible rotational speed is reached, and to still be able to retrieve actual rotational speed information, a rotational speed limiting circuit 28 is activated. This is done as follows. That is, the control terminal 30, which is normally connected to the ground wire 2 by the rotation speed monitoring device 29, is connected to the rotation speed monitoring device 2.
9 from the ground line 2, so that the electronic switch 31 constituted by the emitter-collector of the transistor 32 is in a state where conduction can be controlled. When an induced voltage is generated in the ignition coil 6 by switching off the electronic interrupter 7, the voltage at the primary winding 5 increases to a value sufficient to obtain satisfactory rotational speed information. When this value is reached, Zener diode 40 breaks down. This causes a control current to flow through transistor 32, causing electronic switch 31 to become conductive, while the emitter of transistor 37 becomes conductive.
The connection between the collectors is cut off. transistor 3
These circuit states of 2,37 are maintained via feedback resistor 38. In this circuit state of electronic interrupter 7 and transistor 37, a limited control current for electronic interrupter 7 then flows through resistor 14 and Zener diode 17'. As a result, the electronic interrupter 7 shifts to a new limited conduction state, and the voltage of the primary winding 5 drops to a value at which no ignition spark can be generated at the spark plug 10 in the secondary winding 9. The voltage at the secondary winding 9 is delayed in phase with respect to the voltage at the primary winding 5.

The rotational speed limiting circuit 28 advantageously includes the primary winding 5
is deactivated upon the next activation connection, so that a control current flows through the base-emitter of transistor 35. This control current controls the associated emitter-collector to be conductive. The base of transistor 32 is then connected to ground line 2 by means of transistor 35 and the switch section in speed monitoring device 29, which is closed again. As a result, the electronic switch 31 constructed between the emitter and the collector of the transistor 32 is newly brought into a cut-off state, while the emitter-collector of the transistor 37 is brought into a conductive state again, returning to the normal state. If the rotational speed remains below the maximum permissible value, the normal state is maintained; otherwise, the rotational speed limiting process described above begins anew.

The ignition device shown in FIG. 2 differs from the ignition device shown in FIG. 1 in the following respects. That is, the switch element 17 with a defined breakdown voltage, belonging to the protection circuit 13, consists of two Zener diodes 41, 42 connected in series and whose cathodes are directed towards the tap 16. A circuit branch emerges from the common connection point of the Zener diodes 41 and 42, and this circuit branch is compatible in that it is connected via a resistor 43 to the base of the transistor 32 constituting the electronic switch 31. It's different. The ends of the voltage dividers 14 , 15 that are opposite the primary winding 5 are here connected directly to the ground wire 2 . The collector of the transistor 37 is connected to the connection point 20 via a resistor 44,
Also, the npn transistor 4 is connected via the capacitor 45.
It is connected to the base of 6. transistor 46
The emitter is connected to the ground wire 2, and the collector is connected to the connection point 20 via a series connection of a first induction winding 47 and a resistor 48. The first induction winding 47 is coupled to the second induction winding 50 by an iron core 49 shown in broken lines. One winding end of the second induction winding 50 is connected to the control electrode of the thyristor 51, and the other winding end is connected to the cathode of the thyristor 51. The primary winding 5 is connected between the anode and cathode of the thyristor 51.
are connected in parallel. A resistor 5 connected to the base-emitter shunt of the transistor 46
2 is used for discharging the capacitor 45.

Compared to the ignition system shown in FIG. 1, the operation of the ignition system shown in FIG. 2 differs as follows. That is, when the maximum permissible rotation speed is reached in this device and the electronic switch 31 is ready for switching, the induced voltage increasing in the ignition coil 6 will be reduced to the next level if the rotation speed information is sufficient for operation of the device 11. The value is as follows. That is, at this value, the Zener diode 41 breaks down and a pulse is therefore applied to the transistor 32 forming the electronic switch 31, which subsequently becomes conductive. As a result, the emitter-collector of the transistor 37 becomes non-conductive, and the charging current for the capacitor 45 flows through the base-emitter of the transistor 46. As a result, the emitter-collector of the transistor 46 becomes conductive for a short time, and the resistor A short pulse of current flows through 48 and induction winding 47. This current pulse is transmitted to the inductive winding 50 by electromagnetic coupling. Based on this, the induction winding 50 generates a control current to the thyristor 51. present in the ignition coil 6 and the thyristor 51
Due to the induced voltage applied between the anode and cathode of the ignition plug 10, the anode and cathode become conductive, and as a result, due to the induced current flowing, the induced voltage reaches a value that does not generate an electric spark in the spark plug 10. reduced. In this case as well, on the one hand no ignition spark is generated at the spark plug 10, and on the other hand usable rotational speed information is supplied to the device 11.

After the induced voltage attenuates, the anode and cathode of the thyristor 51 become non-conductive again. When the electronic interrupter 7 and the emitter-collector of the transistor 35 are controlled to be conductive, the rotation speed limiting circuit 28
The above-mentioned switching operation in is again aborted. The capacitor 45 is discharged through the resistor 52 by the conductive emitter-collector of the transistor 37.

Effects of the Invention According to the present invention, even when the engine speed reaches the maximum allowable speed and the speed is restricted, a value corresponding to the speed can be extracted.

[Brief explanation of the drawing]

1 and 2 are circuit diagrams of an embodiment of an ignition device according to the invention, including a speed measurement and limiting device. 1... Current source, 5... Primary winding, 6... Ignition coil, 7... Electronic interrupter, 10... Spark plug,
13... Protection circuit, 28... Rotation speed limiting circuit, 2
9... Rotation speed monitoring device, 41, 42... Zener
Diode, 51...thyristor.

Claims (1)

Claims: 1. An ignition coil whose primary winding together with an electronic interrupter forms a series circuit connectable to a current source and whose secondary winding is operatively connected to at least one spark plug; ignition control method for an internal combustion engine, comprising: a device for extracting a value corresponding to the number of rotations from between the primary winding and the electronic interrupter; and a rotation speed limiting circuit; The induced voltage generated in the ignition coil 6 when the interrupter 7 is cut off is first increased to the value necessary to form a value corresponding to the rotational speed, and then an electric spark (ignited firework) is generated in the ignition plug 10. A method for controlling ignition for an internal combustion engine, characterized in that the ignition is reduced to a value that cannot be achieved. 2 The primary winding, together with the electronic interrupter, forms a series circuit connectable to the current source, and the secondary winding forms an ignition coil in operative connection with at least one spark plug, with a value corresponding to the rotational speed. In the ignition control device for an internal combustion engine, which has a device that takes out the output from between the primary winding and the electronic interrupter, and a rotation speed limiting circuit, the induction that occurs in the electronic switch 31, the protection circuit 13, and the ignition coil Element 14, 17 for reducing voltage: or 51 and rotation speed monitoring device 29
and an element 14, 1 for reducing the induced voltage.
7: or 51 is connected to the primary winding of the ignition coil 6, the electronic switch 31 is connected to the rotation speed monitoring device 29 and the protection circuit 13, and when the maximum allowable rotation speed is reached, the electronic switch 31 is connected to the primary winding of the ignition coil 6. 31 is brought into a state where conduction can be controlled by the rotational speed monitoring device 29, and when the induced voltage generated in the ignition coil 6 reaches a predetermined value when the electronic interrupter 7 is cut off, the protection circuit 13, the electronic switch 31 is turned on, a limited control current is conducted to the electronic interrupter 7 through the elements 14 and 17 for reducing the induced voltage, and the ignition coil 6 is switched to a conductive state. An ignition control device for an internal combustion engine, characterized in that the induced voltage generated in the ignition plug 10 is reduced to a value at which no electric spark (ignition spark) can be generated in the ignition plug 10. 3. The electronic interrupter 7 includes a first transistor 8 protected from overvoltage by a protection circuit 13.
The protection circuit 13 includes a voltage divider 14 connected between the emitter and collector of the first transistor 8,
15, the tap 16 of the voltage divider 14, 15, and the first
connected between the base of transistor 8 of
The electronic switch 31 is composed of a switch element 17 having a predetermined breakdown voltage, and the electronic switch 31 is composed of a second transistor 3
2, the emitter of the second transistor 32 is connected to the emitter of the third transistor 37, the collector of the second transistor 32 is connected to the base of the third transistor 37, and the emitter of the second transistor 32 is connected to the base of the third transistor 37. The collector of the transistor 37 of No. 3 is connected to the voltage dividers 14 and 15 of the protection circuit 13,
The emitter of the third transistor is connected to the emitter of the first transistor 8, and normally, the emitter and collector of the second transistor 32 constituting the electronic switch 31 are non-conductive. The ignition control device according to claim 2, wherein the emitter and collector of the third transistor 37 are electrically connected. 4 One end of the voltage divider 14, 15 is connected to the primary winding 5, and the other end is connected between the emitter and collector of the third transistor 37.
It is connected to the emitter of the first transistor 8 constituting the electronic interrupter 7, and the tap 16 of the voltage divider 14, 15 constitutes an electronic switch 31 via a switch element 40 having a predetermined breakdown voltage. second transistor 3
2, and a feedback resistor 38 is further connected between the base of the second transistor 32 and the collector of the third transistor 37 constituting the electronic switch 31. The ignition control device according to item 3. 5. A switch element 17 having a predetermined breakdown voltage belonging to the protection circuit 13 is composed of a plurality of Zener diodes 41, 42 whose cathodes are connected to the tap 16 side of the voltage divider 14, 15, A connection point between the plurality of Zener diodes 41 and 42 is connected to the base of a second transistor 32 constituting the electronic switch 31, and by switching the second transistor 32 to a conductive state, the primary The ignition control device according to claim 2 or 3, wherein a thyristor 51 connected in parallel to the winding 5 is turned on, thereby reducing the voltage of the primary winding.