DE2131762A1 - Ignition control circuit - Google Patents

Description

DR ING. E. HOFFMANN DIFI .. ING. W. ΕΓΙΧΕ DR. RER. NAT. K. HOFFMANN

PAXRNTAHWiI-TS.

/ D.8000 MÖNCHEN 81 · ARABELLASTRASSE 4. TELEPHONE (0811) 911087 / IO I / Ol

Systematies Inc., St. Paul, Minnesota / USA

Ignition control circuit

The invention relates to an ignition control circuit for an internal combustion engine.

To achieve the object of the invention, such an ignition control circuit according to the invention comprises a voltage or Power generation circuit, which includes a direct current source with a first potential for generating an output voltage is connected to a much higher potential, one to the output of the voltage or power generation circuit related energy storage circuit for at least temporarily storing an electrical charge, devices with a triggerable switching device for switching the

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ORIGINAL INSPECTED

Energy storage circuit in series with the primary winding of an induction coil, and one on the opening and closing of the Ignition interrupter contacts responsive trigger circuit for supplying trigger signals to the triggerable switching device such that the charge in the energy storage circuit flows through the primary winding for a predetermined period of time, when the triggerable switching device receives a trigger signal.

In particular, the invention relates to a solid-state capacitor discharge ignition unit which operates in such a way that A clamp voltage is generated during an ignition control cycle of the system, which is then applied across the ignition coil during of the following ignition control cycle. The intermediate voltage has a much higher potential than that Potential of the battery of the motor, but it is also much lower than that across the secondary winding of the Ignition coil developed voltage. This intermediate voltage has such a value that the spark plugs of the engine are sufficient Ignition voltage through direct transformation of the voltage levels is fed through the ignition coil, so that the ignition coil is essentially as a pulse transformer instead of using a coil Transformation works.

The invention relates in detail to a capacitor discharge ignition circuit for internal combustion engines, the active components of which are essentially entirely body devices are. A power generation circuit is provided which includes a regenerative pulse amplifier and a saturable Transformer for converting the normal battery potential included in a higher tension. A capacitive energy storage circuit is connected to the power generation circuit, and a triggerable switching device enables the

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discharging stored energy through the primary winding of the ignition coil. A trigger circuit which preferably has variable time delay properties is connected to the ignition breaker contacts and is used to trigger to determine the switching device in the course of time.

The system according to the invention has the advantage that in the case of different battery states of charge one essentially constant energy transfer can be maintained. Furthermore, the use of a transistorized trigger circuit results a positive semiconductor switch for the semiconductor switch used to discharge the stored energy through the ignition coil shaped impulse for triggering, during this in turn a high ignition voltage available during starting Provides. Further, by providing a variable time delay control for the trigger circuit becomes a special one "Delay" function achieved which to adjust to the special requirements of the engine can be adjusted.

These and other objects and advantages will become clear and understandable from the detailed description that follows in connection with the drawing, in which embodiments of the invention are shown. In the drawing demonstrate:

Fig. 1 is a schematic circuit diagram of a preferred embodiment a capacitor discharge ignition circuit according to the invention,

Fig.2 a variable ignition delay circuit, suitable for the Use in the trigger network according to FIG. 1, and

Figure J5 shows an alternative arrangement for the variable ignition delay circuit after Pig. 2.

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In Pig. 1 of the drawing is a schematic circuit diagram of the capacitor discharge ignition circuit. This circuit comprises an enclosed with a dashed line power generation circuit 10, an enclosed with a dashed line energy storage circuit 12, an enclosed with eir.er dashed line discharge circuit 14, an enclosed with a dashed line trigger circuit Io ird an enclosed with a closed line STEU "rkrt'ir. 17 for on / off.

The power generation circuit 10 as part of. .jyst «» - r, ·.-.- encompasses one generally with the reference symbol Il be: vi -.-. \ :. ot. · * ;. Transformer and a general mi *, dorr ·. Βο; ·. \; _ί . ·;:;: ν · 1 ^. ·. <> :. * ·. designated transistor amplifier. The TriU.üfciTuitor 1 has a adaptable core 22 on which. oine Pr * .rKrwicklung 24, a secondary winding 2ύ and oii.e RUekkoppl - »: igewicklung 28 is wound. The primary winding 2h i.At oi:; ·· :. first connection 30, which has a loiter ίϋ tr.it «.» ir ^ r. Terminal 34 is connected. The second connection 3o of the IrI secondary winding 24 is connected to the Rr.Jbterelectrode 4o of the transistor amplifier 20 via a semiconductor diode 30. The collector electrode 42 of the transistor amplifier 20 is connected to a point of fixed potential (earth). One connection of the feedback winding 28 is also connected to the connection 36, while the other connection 44 of the feedback winding 28 is connected to the base electrode 48 of the transistor amplifier 20 via a resistor 46. Terminal 34 can be connected to the positive terminal of a direct current storage battery normally associated with the engine. The negative terminal of the battery is connected to ground.

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209809/1043 bad original

A first terminal 50 of the secondary winding 26 of the transformer 18 is connected by a conductor 52 to the first terminals 54 and 56 of a pair of capacitors 58 and 60. The capacitors 58 and 60 are the essential part of the energy storage circuit 12. The other terminal 62 of the secondary winding 26 is connected to the other terminal 68 of the capacitor 58 by means of a parallel circuit of a resistor 64 and a diode 66, the terminal 68 forming a connection point . The cathode electrode of the diode 66 is connected to the connection point or terminal 68 via a conductor 70. A parallel circuit of a resistor 72 and a diode 74 is arranged between the connection point or the connection 68 and the other connection 76 of the capacitor 60, the connection 76 also forming a connection point.

The discharge circuit 14 for the energy has a load, which in this case consists of the primary winding 78 of the Induction or ignition coil of the ignition system, with a resistor 80 connected in parallel with the primary winding 78 is. The parallel connection of resistor 80 and primary winding 78 is via a conductor 82 to the terminal 56 and connected to earth via a conductor 84. The discharge circuit also contains a controlled silicon rectifier (SCR), which is indicated generally by the reference numeral 86 and includes an anode electrode 88, a cathode electrode 90 and has a control electrode 92. The anode electrode 88 is connected by a conductor 94 to the connection point or terminal tied together. The cathode electrode 90 is connected to a grounded connection 98 via a diode 96. Terminal 98 hangs further via a diode 100 with the connection point or terminal 76 together. Further, a resistor 102 connects the

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Control electrode 9 ^{2 of} the controlled silicon rectifier 86 with the grounded terminal 98.

In the trigger circuit 16, which is from a dashed Line is surrounded by a semiconductor switching device generally designated by the reference numeral 104, a capacitor I06, the breaker contacts I08 of the ignition system with an optionally provided conventional capacitor I09 as well as others Includes parts to connect the main parts of the trigger circuit. In detail, the semiconductor switching device 104, which here is shown as an npn transistor, a pair of output electrodes 110 and 112 and a control electrode 114. The output electrodes 110 and 112 are connected to the capacitor I06 between a grounded terminal 116 and the cathode electrodes 90 of the silicon controlled rectifier 86 connected in series. One connector 118 for one Key switch can be connected to a source of positive potential, which is the positive terminal of the storage battery of the engine can be. The connection Il8 is via a resistor 120 and a diode 122 with a connection point 124 between the output or collector electrode 110 of the semiconductor holding device 104 and one terminal of the capacitor I06. The connection 118 for the key switch is further through a resistor 126 to the ungrounded connection 128 of the Interrupter contacts I08 in connection. This ungrounded connection 128 is also connected to a connection point I30 between the first connection of a resistor Ij52, the anode of a Diode 134 and the cathode of a diode I36 in connection. Of the the other connection of the resistor 132 is via a capacitor I38 and via a conductor l40 to the connection point or connection 76 in connection. A capacitor 142 is across the other terminals of the diodes I36 and I38, i.e. across their Cathode or anode switched. A resistor 144 connects the Connection point between resistor I32 and diode 134

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with the base or control electrode 114 of the semiconductor holding device 104. A resistor 146 is connected between the control electrode 114 and the grounded terminal 116 of the semiconductor switching device 104.

The control circuit 17 of the system for on / off, which is enclosed by a dashed line, has a first transistor amplifier 148, a second transistor amplifier 150 and coupling resistors I52, 154 and I56. Resistor I52 couples the collector electrode of the transistor amplifier 148 with a connection point I58 between the anode of the diode 134 and a connection of the resistor 144. The coupling resistor 154 connects the emitter electrode of the transistor amplifier I50 with a ground connection I60. Of the Ground connection I60 is connected to terminal 118 via a diode 162 connected for the key switch. Finally, the coupling resistor I56 connects the collector electrode of the Transistor amplifier I50 with the base electrode of the transistor amplifier 148. The emitter electrode of transistor amplifier 148 is connected by means of conductor 164 to the positive terminal connected to the battery.

The connection point or terminal 36 between the primary winding 24 and the feedback winding 28 of the transformer 18 is connected via a capacitor 37 to a connection point 39, to which a first connection of an I. Resistor 41 and the anode electrode of a diode 43 are connected is. The cathode of the diode 43 is with the connection point or Terminal 76 connected.

After the details of the switching elements and their connections have been shown in detail, the Operation of the preferred embodiment of the invention will be considered.

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The general purpose of this system is to provide an intermediate voltage during an ignition cycle of the engine ignition system which is discharged via the ignition coil during the next ignition cycle. The intermediate voltage has such. Size that they generate enough ignition voltage through the direct transformation of the voltage through the ignition coil the spark plugs there. With this arrangement, the ignition coil then becomes a pulse transformer instead of a coil with transformation, as is the case with known systems.

Assume first that the positive terminal of the battery used in the system is connected to terminal 34 while the negative terminal of the battery is connected to ground. The power generation circuit 10 operates to convert battery power into an intermediate voltage which has a higher value than the voltage of the battery. This higher intermediate voltage is stored in the energy storage circuit 12 for later discharge through the primary winding J8 of the ignition coil. The power generation circuit comprises the transformer 18 and the semiconductor or transistor amplifier 20 ₀

When the key switch of the terminal 118 is turned on, a current flows through the resistor 41 and the diode 43 and charges the capacitor 60 as it is through the polarity denominations in Fig. 1 is indicated. if the capacitor is discharged via the discharge circuit 14 in a manner as will be described below A current pulse from terminal 34 via capacitor 37 of the battery through the primary winding 24, the capacitor 37 and the diode 43 and the silicon controlled rectifier 86 and the diode 96 pulled to earth. The one through this impulse generated current flow through the primary winding induces a

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Voltage in the feedback winding of the transformer 18, and this feedback voltage has such a polarity on (see polarity markings on the transformer) that the transistor amplifier 20 becomes more conductive. This diminishes the impedance of the transistor amplifier 20 and thereby enables a greater flow of current through .den conductor 32, the primary winding 24, the diode 38 and the emitter-collector path of the transistor amplifier 20. that the feedback winding and transistor operate in a regenerative manner to rapidly saturate the transformer 18 with a saturable core. The current flow through primary winding 24 and transistor amplifier 20 continues until the transformer core is near saturation, at which point the one generated by the feedback winding 28 Feedback current is reduced considerably. The transistor then switches off and the current stops, through the primary winding 24 to flow.

During this period of regenerative action before the Transformer saturation flows in the secondary winding 26, a very small current. As soon as the current flows through the primary winding iif the saturation ceases, the in the primary winding Inductively stored energy is transformed to the secondary winding 26 and only flows through the diode 66 and the conductor 70 to charge capacitor 58. When the charge on capacitor 58 equals the residual charge on capacitor 60 is, the current flowing through the secondary winding 26 flows through the diode 66 and the diode 74 for charging the capacitors 60 and 58. The resistor 64 connected in parallel to the diode 66 serves as a bleeder resistor for the capacitor 58, in order to charge the capacitor in the direction of the induced voltage during the current flow in the primary winding enable. This enables the secondary current to flow

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-ΙΟ-In the direction of the diode polarity; ! immediately after the through the transformer saturation caused interruption of the Current flow through the primary »! Until effect of resistance 64 as a bleeder resistor then reduces the cut-off voltage, which is returned to the primary winding and over the junction between the emitter and collector of the Transistor amplifier 20 is applied to an acceptable level, thereby avoiding voltage breakdown of the transistor will.

The transistor of the transistor amplifier 20 is preferably a highly conductive low voltage transistor, e.g. a Hoehstrois-Germanium-Traasistor · By using the semiconductor diode 38 in series with the emitter-base circuit of the transistor of the transistor amplifier 20, any fault current at elevated temperatures acts as a bias in the opposite direction, which e5.nen hinders further fault current flow. The semiconductor diode 358 also serves to provide a fixed residual voltage in the coupling circuit in order to reduce the risk of the inductance of the primary winding resonating with the capacitance in the circuit and the occurrence of natural oscillations to a minimum.

The above cycle of effects is repeated for each Firing the silicon controlled rectifier (SCR) 86, whereby the capacitor βθ after each ignition process back to the desired Potential charged w

The resistor 72 serves to reduce the charge on the capacitor βθ to derive when the "system is turned off."

The one connected in parallel to the primary winding 78 of the sin coil Resistor 80 is a protective resistor which provides a discharge path for the capacitors 58 and 60 in the event that

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that the primary winding 78 is opened or switched off. The value of the resistor 80 is chosen so that the controlled Silicon rectifier 86 for a maximum amount of time and with a minimum of reduction in the output energy of the coil can remain conductive so that the power generation circuit is not triggered while capacitors 58 and 60 are on substantial voltage are charged. With a limited charge on the capacitors, the cutoff voltage will be in the primary winding of the transformer 18 at the end of the regeneration cycle brought to a minimum in order to thereby cause a voltage breakdown of the transistor of the transistor amplifier 20 impede.

The control and discharge circuit 14, which is enclosed by a dashed line, is used to discharge the on The capacitors 58 and 60 store charges through the primary winding 78 of the ignition coil when the silicon controlled rectifier 86 is controlled. Specifically, flows when the silicon controlled rectifier 86 is turned on and so represents a low impedance, the charge on capacitor 60 to terminal 76, through conductor 94, and from the Anode electrode 88 to cathode electrode 90 of the controlled Silicon rectifier 86, through diode 96 and conductor 84, through primary winding 78 of the ignition coil and the conductor 82 to the other terminal 56 of the capacitor 60. By use of the diode 96, the cathode of which is connected to ground as shown, can have a negative pulse to trigger the controlled Silicon rectifier can be used in the conductive state.

The silicon controlled rectifier 86 is switched on when the cathode electrode of the rectifier is negative Pulse from the capacitor I06 is fed into the trigger circuit l6.

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Specifically, when the cathode electrode 90 of the controlled When a negative pulse is applied to silicon rectifier 86, current from grounded terminal 98 passes through the resistor 102 connected to the control electrode 92 of the rectifier. As mentioned above, this switches the controlled one A silicon rectifier and allows a much larger discharge current to flow from the capacitor 60 through the rectifier and through the primary winding 78 of the ignition coil,

Since the ignition coil is inherently inductive, the current cannot flow immediately after the capacitors have discharged 58 and 60 stop. The current continues to flow until a peak reverse voltage appears on capacitors 58 and 60. At this point only capacitor 60 reverses the direction of current flow through the ignition coil and through the diode 102 µm until it is charged in the forward direction to a voltage which punctures the out of this oscillation cycle recovered unused energy is during the opposite Current flow, the controlled silicon rectifier 86 is made non-conductive, and since the pulse vn his Control electrode 92 has been removed, it turns off and maintains the residual charge on the capacitor 60. The capacitor 58, however, remains charged in the reverse direction in order to remove it of transient voltages from the power generation circuit 10. The resistor 1 ^ 2 and the capacitor I38 act to reduce the reapplication of potential to the controlled silicon rectifier 86 for the purpose of triggering,

Reliable triggering of the controlled silicon alignment device 86 to ensure under all operating conditions, a trigger circuit 16 was provided with a negative pulse. As : shown, the trigger circuit consists of resistor 120, diode 122, capacitor I06, resistor 102, the

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Diode 96 and the semiconductor switching device 104, which one basic ignition pulse is generated while resistor 126, breaker contacts I08, diode Ij34, diode I36, the resistor 144, the resistor 146 and the capacitor 142 the conductive state of the semiconductor switching device 104 steer.

When the key switch of port 11 * 8 is turned on a current also flows through the resistor 120 and diode 122, through capacitor I06 and diode 96, to charge capacitor I06 when the break contacts 108 are closed. If the breaker contacts are open, a current flows from the terminal 118 through the resistor 126 and diode 1J54 and charges capacitor 142. A current flows further through the resistor 144 and through the base-emitter path, i.e. from the control electrode 114 to the output electrode 112 of the semiconductor switching device 104, which is connected in parallel with the resistor 146. The different values of the Switching elements are chosen so that there is an increase in the conductivity of the transistor or the semiconductor switching device 104 results in a rapid flow of current from ground through resistor 102, control electrode 92, the junction point on the cathode side of the silicon controlled rectifier 86, through the capacitor I06 and the transistor or semiconductor scarf t device 104 to earth ensures. Once the capacitor I06 is discharged, the output or collector electrode remains 110 of the transistor or the semiconductor switching device 104 essentially at ground potential in order to prevent that changes in the voltage from the key switch cause the silicon controlled rectifier 86 to be retriggered cause open interrupter contacts I08.

If the breaker contacts I08 are closed again, the charge on capacitor 142 maintains conduction in the '; Base circuit of the transistor or the semiconductor switching device

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for a predetermined limited period of time to the breaker contacts to calm down and thereby eliminate difficulties that would otherwise be caused by contact bouncing would occur. After this predetermined period of time has elapsed, the conduction of current through the transistor ceases or the semiconductor switching device 104, and the diode 1354 blocks any current flow back to the breaker contacts. When the semiconductor switching device 104 is turned off, is the capacitor 106 is charged again via the resistor 120 and the diode 122 in the manner described above. The diode 122 results a blocking effect that enables capacitor 106 to assume the highest voltage applied to this circuit during the duration of the closed breaker contacts 108. This gives an advantage in cold weather, especially when starting the engine when the battery voltage is just about to come has its lowest point when igniting *

The diode I36 is used as a shunt for high signals Potentials required by the distributor during the periods high spark potential can be returned. It protects the diode 1 ^ 4 from a voltage breakdown. In some motor vehicles, a residual voltage can be fed back to the ignition circuit; when the engine is running. These can be fed to the voltage comparison circuit, which works with the charge indicator lamp in the instrument panel, the in turn to display the charging process in the power generation system of the engine. It has been shown that this voltage can have a sufficiently high value to be sufficient To give charge current in the capacitor I06 for further ignition of the controlled silicon rectifier 86. Has this difficulty to overcome is the control circuit 1? intended for on / off. The control circuit 17 contains a voltage comparison circuit, which senses when the voltage from the key switch is below a predetermined value compared to mil; the battery

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voltage drops. When this is applied, current flows continuously to the base of the transistor or the semiconductor switching device 104 and prevents reloading of the capacitor 106, whereby the system is switched off.

When the key switch is switched on, a current flows through the junction between the base and emitter of the transistor amplifier 150 and thereby brings it into a conductive state. Since there is no resistance in the base circuit of the transistor, the voltage across resistor 154 is essentially the same the battery voltage. A resistor I5I is used to stabilize the "off" state of the transistor amplifier I50 when the key switch to terminal 118 is open, and diode 162 shunts induced transient signals which occur at Opening the key switch can result in destruction of the transistor amplifier I50.

When the voltage of the key switch drops significantly below the battery voltage, a current is drawn from the terminal 34 of the battery through the transition between emitter and base of transistor amplifier 148, through resistor I56, through the collector-emitter path of transistor amplifier I50 and flow through resistor 154 to ground connection I60. This results in a current flow through the emitter-collector path of the Transistor amplifier 148 through resistor I52 and through resistor 144 to the base circuit of the transistor or the semiconductor switching device 104. This current flow is continuous under the assumed conditions and prevents charging of the capacitor IO6, since the normal charging current for the capacitor IO6, which normally flows through resistor 120 and diode 122, across the collector-emitter path of the Transistor or the semiconductor switching device 104 is shunted to ground. When the voltage of the key switch Is zero, no current can flow from the key switch to capacitor 106 and need transistor amplifiers 148 and I50.

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only between a predetermined voltage level of the key switch below the battery voltage up to a voltage level that triggers the controlled silicon rectifier 86 in the conductive state is no longer sufficient to work.

It should be noted that by connecting the circuit from terminal j54 of the battery to junction point I58 which capacitor 142 and resistor 154 are common, this capacitor 142 acts as a filter for any short duration transition pulses introduced into the key switch circuit and could lead to conduction of the transistor amplifier when the engine is running and the breaker contacts are closed.

In some use cases it may prove desirable prove a means for controlling the point in time in the cycle at which the controlled silicon rectifier is ignited, to be provided in order to have the possibility of an advanced or retarded ignition of the engine. Fig. 2 shows the way in which a small number of parts can be added to the system of Fig.l to give this feature. In Fig.2 Those parts which are identical to those shown in FIG. 1 are denoted by the same reference numerals as in FIG.

The time delay circuits shown in Fig. 2 will, when used, the ignition timing over a certain one Decelerate the low speed range of the motor and will effectively cut off above the given speed range.

In FIG. 2, a transistor 166 is added in the base circuit of the transistor or semiconductor switching device 104. In particular, the emitter-collector path of transistor 166 is in series between resistor 144 and the base or Control electrode 114 of the transistor or semiconductor

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switching device 104 switched. The base electrode of transistor 166 is by means of a conductor 168 with a Connection point 170 connected to which a first terminal of a resistor 172 and a resistor 174 are connected is. The other connection of the resistor 172 is with Connected to ground, while the other terminal of resistor 174 is connected to the emitter terminal of a transistor I76 is. The base electrode of transistor I76 is through a Resistor I78 connected to connection point IJO. the The collector electrode of transistor I76 is above a variable Resistor I80 with the connection of the key switch in connection. Finally, a capacitor 182 connects the collector electrode of transistor I76 to the Connection point I30.

The transistor 166 is when the breaker contacts open 108 do not conduct until the voltage across the opposing tand 172 is small enough to allow sufficient current to flow from the breaker contacts I08 through the diode Ij54, through the resistance. 144, through the transition between the emitter and base of the transistor I66 and through the resistor I72 to surrender to earth. The current flow through the emitter-base path of transistor I66 reduces that from the emitter-collector path of the transistor 166 shown impedance so that a base 8, current for the transistor or the semiconductor scarf teinrichtung 104 is provided. With such a base current, the transistor or the semiconductor switching device 104 manager and works in the context of Pig. I described Way to cause the silicon controlled rectifier 86 to fire.

A delay in the conduction of transistor 166 is caused by a charge on capacitor 182 flowing through transistor I76 and resistors 174 and 172,

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when the breaker contacts 108 are near battery voltage (breaker contacts open). The resistor I78 causes that the transistor I76 is conductive when the breaker contacts 108 are open and non-conductive when the breaker contacts are closed.

If the breaker contacts I08 are closed, becomes the junction of capacitor 182 and resistor I78 will be at ground potential, and capacitor 182 will be charged at a rate determined by the RC time constant of resistor ISO and capacitor 182 is determined. Assuming that the charge on capacitor 182 is sufficient, 12m the voltage across the resistor 172 exceed the junction voltage of transistor 166 To leave, transistor 166 will be held nonconductive until capacitor 182 is nearly discharged. The condenser 182 continues to deliver power until it is reversely charged. With this reverse charge, if the rest time is not is sufficient to achieve a forward charge on capacitor 182, no delay in triggering of the transistor or the semiconductor ehalt device 104 occur. Resistor I74 is a stabilizing and limiting resistor to control the flow of charge from the capacitor 182 to earth.

The delay provided by the circuit of FIG is useful when starting and at low engine speeds in order to achieve an ignition delay, which means that the ignition is too early during cranking and control of exhaust discharge Prevents idling, older circuit can be set 'werdeni_öai, ef; .b # i every ^ tilM'eöhtieÄ ^ tlssaftlwert becomes ineffective, around the normal Zttadzeitpunktteueirouig while accelerating and work on the engine under load - ^ ksam.

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A factor in the adjustment of the circuit according to FIG. 2 is the idle time, i.e. the length of time during which the interruption Contacts between ignitions expressed in degrees of distributor rotation or as a percentage of the time between Ignitions are closed. The embodiment of Fig. 3 shows a similar circuit for controlling the ignition timing of the controlled silicon rectifier 86, in which, however, the rest time is no longer a factor for the adjustment. In Fig. 3 are again those parts which have already been described in connection with FIGS. 1 and 2 have the same reference numerals as in these both figures used, provided.

The circuit of Figure 3 is quite similar to that of Figure 2 with the exception of an added additional pair of transistor amplifiers or transistors 184 and 186. Transistors 184 and 186 may be a multiple junction device or, alternatively, two two junction devices. The emitter electrode of the transistor 184 is connected to the connection point I50 and the base electrode is connected to the same connection point via a resistor 188. The collector electrode of the transistor is connected to the base electrode of the transistor 186 and through a resistor 190 to ground. The collector electrode of transistor 186 is connected to the base electrode of transistor 184. A resistor I92 connects the emitter electrode of the transistor 186 ⁵ to its base electrode, and the emitter electrode of the transistor 186 is connected to a first terminal of the capacitor 182 for the time delay.

The collector electrode of the transistor I86 stands apart from the Connection to the base electrode of transistor 184 via a Resistor 194 and a capacitor I96 connected to ground.

As mentioned above, the circuit of FIG. 3 is very similar to the circuit of FIG. In addition, they are Transistors 184 and 186 are provided to enable the capacitor 182 to begin recharging as soon as it is initially

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has been discharged as a result of the opening of the breaker contacts. When the breaker contacts open, a current flows through the junction between the emitter and base of the transistor 18 ¹ IJ, through the resistor 1 ° A and the capacitor 196 to earth. This causes transistor 184 to conduct through its collector to the base of transistor 186 and a current through the base-emitter path of transistor 186 and through capacitor 182, a diode 198, the collector-emitter path of transistor I76 and the Resistors I72 and ΐγ4 can flow to earth »The effect on the discharge of the capacitor I82 is as described above. The collector circuit of the transistor I86 keeps the current flow through the transistor 184 upright of the circuit allows the current to continue flowing through capacitor 182, until it is charged in the opposite direction. When the capacitor 3.82 is reversely charged, the transistors I86 and 184 turn off and the capacitor 182 begins _{to discharge to ground as a result of the current from the key switch through the resistor, 3.SQ 5,} the capacitor 182 and the resistors I92 and to ground _o When the Lad®geschwind! ness is enough ,, to Errei take a charge in Vorwirtsrichtung on the capacitor 182 ^ they fird to an occurrence of a delayed effect lead _a tn®mi the Unterforecherlcontäkte next Zündsylelus open "If the charging rate is not sufficient to charge in the forward direction on the capacitor 182 to h®iTLi? lmn _D , the circuit Ice has an effect on the ignition timing. Ea the rJiederiadiing the capacitor 182 in the forward direction Ventilation QlTMt ₀ soteld it is discharged ,, the rest time list No Wirfeimg on fii © ¥ © ^ G5g © rtiiagäiseito The 3iod © I98 prevents äl® reversed © charge ä @ s! © aiensatörs 182 immediately over the resistances 192 mid. I90 and the transition from the base to the transistor 176 will discharge «,

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The circuit which forms the preferred embodiment of the invention and in which a transistorized controller of the trigger circuit is used for the controlled silicon rectifier, results in more positive shaped pulses for the trigger • and has the advantage of "holding" the highest voltage available during cranking. The circuit allowed further the retention of the conventional capacitor over the breaker contacts in the ignition system, whereby the System can easily be switched from "discharge ignition" to conventional ignition for system maintenance. Further a fixed delay in the restoration of charge on capacitor 106 creates the effect of contact bounce not only sifted out, but completely suppressed. Double ignition of the controlled silicon rectifier is therefore avoided. Furthermore, the circuits for modifying the ignition timing according to FIGS. 2 and 3 result in a special delay function which is used to adapt to the special requirements of the motor is adjustable.

While a preferred embodiment of the invention has been described and illustrated, it will be apparent to those skilled in the art that various modifications and changes can be made. For example, if a positive earth system should be desired, it is advantageous to discharge capacitor 60 through a controlled semiconductor hold device (SCR 86) to earth rather than through the primary winding of the ignition coil. In this way, moisture or leakage current paths to ground on the primary winding of the ignition coil would not cause capacitor 60 to discharge between ignitions. For a positive earth system it is only necessary that the polarities of all semiconductors and the battery polarity be reversed. The SCR device in the form of a triac or other bipolar device which can be used « can still be de-

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neither negative nor positive using the above Principles are triggered. Accordingly, the invention described herein is intended only in accordance with the scope of the claims may be limited.

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Claims (1)

Claims (1st / ignition control circuit for an internal combustion engine, characterized by a voltage or energy generation circuit (10), which uses a direct current source with a first potential to generate an output voltage with a significantly higher Potential is connected to an energy storage circuit connected to the output of the voltage or energy generation circuit (1 2) for at least temporarily storing an electrical charge, devices with a triggerable switching device for connecting the energy storage circuit in series with the primary winding (78) of an induction coil, and one on the opening and closing of the ignition breaker contacts (I08) responding Trigger circuit (16) for supplying trigger signals to the triggerable switching device such that the charge in the energy storage circuit for a predetermined period of time by the Primary winding (78) flows when the triggerable switching device receives a trigger signal. 2. Device according to claim 1, characterized in that that the voltage or energy generating circuit (10) contains a saturable transformer (18) having a primary winding (24), a secondary winding (26) and a feedback winding (28), a semiconductor current control device (20) having a first and a second electrode and a control electrode, devices for connecting the first and second electrodes in series with the primary winding and through a direct current source, means for connecting the feedback winding to the control electrode in such a way that when a current pulse flows through the primary winding a voltage is generated in the feedback winding to allow an additional current to flow through the primary winding and to enable the semiconductor current control means in a regenerative manner and a voltage of high potential to generate across the secondary winding. -24- 209809/1043 ^. Device according to claim 2, characterized in that that the energy storage circuit (12) is connected to the secondary winding (26) and at least one capacitor (58, 60) with first and second terminals, means for connecting one of the terminals (54, 56) to a terminal (50) of the secondary winding (26) and a device (66, 74) which conducts current in one direction and which connects the second connection to the other terminal (62) of the secondary winding connects. 4. Apparatus according to claim 1, 2 or 3, characterized in that the triggerable switching device consists of one controlled silicon rectifier with a first and second electrode and a control electrode, the first .and second electrode in series with the primary winding of the induction coil and connected to the energy storage circuit and means for connecting the control electrode to the Trigger circuit (16) are provided. 5. Apparatus according to claim 1, characterized in that that the trigger circuit comprises a semiconductor switching device with a pair of output electrodes and a control electrode, a first capacitor connected in series with the pair of output electrodes and a control electrode, a second capacitor means connected in series with the pair of output electrodes and the triggerable switching means for connecting the control electrode to the ignition breaker contacts, devices for charging the second capacitor a predetermined voltage, when the ignition breaker contacts ■ are closed, and to make the semiconductor switching conductive. device, when the ignition breaker contacts are open. -25-209809 / 1043 6. Apparatus according to claim 1, characterized e t that the triggerable switching device comprises a triac which has a pair of output electrodes in series with the Primary winding (78) of the induction coil and the energy storage circuit are connected, and has a control electrode connected to the trigger circuit. 7. Apparatus according to claim 6, characterized in that that the devices connecting the control electrode to the ignition breaker contacts (108) form a time delay network (Fig. 2 and 3) for holding the semiconductor switching device in the non-conductive state for a predetermined period following the opening of the ignition breaker contacts. 209808/1043