US3612023A

US3612023A - Ignition arrangement for internal combustion engines

Info

Publication number: US3612023A
Application number: US838423A
Authority: US
Inventors: Gerhard Sohner; Gert Strelow
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 1968-07-04
Filing date: 1969-07-02
Publication date: 1971-10-12
Anticipated expiration: 1988-10-12
Also published as: YU165769A; DE1764609A1; FR2014502A1; AT303457B; GB1269710A; YU32055B; ES369077A1; DE1764609B2; SE347549B

Abstract

An ignition arrangement for internal combustion engines in which an induced voltage charges an ignition capacitor. A magnetic member driven by the engine induces the charging voltage within a charging coil and, moreover, induces a control voltage within another coil for controlling an electronic switch. When the latter is turned on, the capacitor discharges through the primary winding of an ignition transformer to generate a voltage for firing the spark plugs. Ignition of the fuel-air mixture is inhibited when the engine is rotating in the wrong direction.

Description

United States Patent [72] Inventors Gerhard Sohner Geradstetten;

Gert Strelow, Stuttgart-Stammheim, both of Germany July 2, 1969 Oct. 12, 1971 Robert Bosch GmbI-I Stuttgart, Germany July 4, 1968 Germany Appl. No. Filed Patented Assignee Priority IGNITION ARRANGEMENT FOR INTERNAL COMBUSTION ENGINES 16 Claims, 7 Drawing Figs.

US. Cl 123/149 A, 123/ 146.5 A

Int. Cl F02p 3/06 Field of Search 123/1465,

148 AC, 148 E, 149, 149 A, 149 D,4I; 310/70 References Cited UNITED STATES PATENTS 1,999,703 4/1935 Lesage 123/148 AC 3,356,896 12/1967 Shano 123/148 E 3,362,389 1/1968 Johnson 1 H 123/41 X 3,435,264 3/1969 Brand et a1. 123/148 AC 3,465,739 9/1969 Burson 123/149 Primary Examiner-Laurence M. Goodridge Attorney-Michael S. Striker ABSTRACT: An ignition arrangement for internal combustion engines in which an induced voltage charges an ignition capacitor. A magnetic member driven by the engine induces the charging voltage within a charging coil and, moreover, induces a control voltage within another coil for controlling an electronic switch. When the latter is turned on, the capacitor discharges through the primary winding of an ignition transformer to generate a voltage for firing the spark plugs. Ignition of the fuel-air mixture is inhibited when the en gine is rotating in the wrong direction.

IGNITION ARRANGEMENT FOR INTERNAL COMBUSTION ENGINES BACKGROUND OF THE INVENTION the control voltage for the dischargeswitch, an inductively influenced control winding is provided, and the inductive effect upon the control winding takes place separately from that upon the charging winding.

Such ignition arrangements find utility when no battery is available for energizing the ignition arrangement. By storing the ignition energy within an ignition capacitor, the secondary winding of the ignition transformer receives a high-voltage pulse with steep rising edge at the instant of ignition. Asa result of this design, even spark plugs with soiled electrodes become sparked reliably through the electrical arrangement. The control for the ignition process can, thereby, be carried out without the use of mechanical switches which become readily soiled through pitting and oil coatings. Such mechanical switches, therefore, interfere with unobstructed operation of the ignition arrangement. I

A preferred application of such an ignition arrangement, is for two-cycle internal combustion engines for driving motor vehicles with'two wheels. Two-cycle internal combustion engines are inclined to rotatein the wrong direction upon starting or when in idling state. When such a situation arises in a motor vehicle, such sudden and surprising motion in the undesired direction may resultin accidental conditions.

Accordingly, it is an object of thepresent invention to provide an ignition arrangement, in accordance with the aforementioned design, in which the internal combustion engine cannot rotate in the incorrect direction. This object is achieved through the present invention by providing that the ignition capacitor which is charged through a charging coil, will not discharge at the instant of time for carrying out an ignition process, when the engine rotates in the wrong direction. In this regard, a control voltage for turning on an electronic discharge switch is generated through inductive effects upon a control winding for compressed mixtures.

SUMMARY OF THE INVENTION An ignition arrangement for internal combustion engines in which a capacitor is charged to a level where it can provide the ignition voltage necessary for generating a spark across the spark plugs. A charging coil has a voltage induced within it through a rotating magnetic system, and this voltage is used -to charge the capacitor. Upon triggering of a controlled electronic switch, the capacitor is discharged through the primary winding of an ignition transformer. As a result of such discharge, a high-voltage pulse is induced within the'secondary winding of the ignition transformer, and the spark plug is thereby'fired. The controlled electronic switch is triggered through a control voltage induced within a control coil also influenced by the magnetic system which is moved past this control coil. The control'voltage is induced through rotation of the magnetic system so'that when the engine is rotating in the wrong direction, ignition of the fuel-air mixture within the engine is inhibited. Such inhibition'of the ignition of the mixture is accomplished by providing bypass circuitry in parallel with the ignition capacitor for discharging the latter appropriately to assure that the ignition energy will not be available at the firing instant, when the engine is rotating in the wrong direction.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims.

The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a functional schematic diagram of an ignition arrangement in which ignition at an undesired instant of time is avoided through an electronic discharge switch;

FIGS. 2 to 4 are functional schematic diagrams of ignition arrangements in which an ignition capacitor is discharged in advance of an instant of time at which ignition is to be avoided;

FIGS. 5 and 6 are functional schematic diagrams of ignition arrangements in which ignition at a predetermined instant of time is avoided by producing ignition in advance of that instant;and 1 FIG. 7 is a cross-sectional view taken along the line VlI VII in FIG. 6.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawing, and in particular to FIG. 1, a discshaped magnetic system 1 is driven by the crankshaft of an internal combustion'engine, not shown, while the latter is in operation. The disc-shaped magnetic system 1 has at least one north-pole segment N, as well as one south-pole segment S at the rim. As the result of the motion of the magnetic system I, a charging coil 2 which is stationary, and an equally stationary control winding 3 are influenced as a result of the inductive coupling between these coils and the rotating member 1. The charging'coil 2 is mounted upon an E-shaped ferromagnetic core 4, which has its poles 5, 6, 7 facing the magnetic system 1. One terminal of the charging coil 2 is connected to ground potential through the connection 8, whereas the other terminal of this coil is connected to the anode of a charging rectitier 9. An ignition capacitor 10 is connected between the cathode of the charging rectifier 9 and ground potential. The series circuit containing the primary winding 11 of an ignition transformer I2 and the switching path A-K of an electronic discharge switch 13 is also connected between the cathode of the charging rectifier 9 and ground'potential. This series circuit is, accordingly, connected in parallel with the capacitor 10. The secondary winding 14 of the ignition transformer 12 is connected in series with a spark plug 15, and the series combination of this spark plug 15 and the secondary winding'l4 is connected between the ground potential connection 8 and the junction of the primary winding 11 and the discharged switch The electronic discharged switch 13 may be in the form of, for example, a thyristor which has a control electrode G connected to the cathode of a diode 16. The anode of this diode I6 is connected to one terminal of the control winding 3. The other terminal of the control winding 3 is connected to ground potential through the ground connection 8. The control winding 3 is mounted upon a U-shaped magnetic core 17 which has

poles

18, 19 facing the magnetic system 1.

In operation of the ignition arrangement described thus far, it is essential that the two-cycle internal combustion engine used in conjunction with the arrangement of FIG. I, be rotating in the proper direction. In such correction direction, the magnetic system 1 with its poles N and S, will rotate in the direction of the arrow P and passes first the poles 5,6,7 of the ferromagnetic core 4. This motion of the magnetic system I, in this manner, causes an alternating voltage to be induced within the chargingcoil 2. The positive half wave of this AC voltage reaches the ignition capacitor 10, by way of the charging rectifier 9. The ignition capacitor stores electrical energy and its electrode. connected to the charging rectifier 9 becomes thereby positive. The electrode of the capacitor connected to the ground connection path 8, on the other hand, acquires a negative potential as a result of the charging process.

With further rotation of the magnetic system I, the magnetic poles N and S move past the poles l8 and 19 of the ferromagnetic core 17. As a result of such motion of the magnetic system I, the control winding 3 has an AC voltage induced within it. This AC voltage reaches with its positive half wave, the control electrode G of the electronic discharge switch 13, by way of the diode 16. The circuit path A-K of the discharge switch 13 is thereby made conductive, and the ignition capacitor 10 discharges through the primary winding 11 of the ignition transformer 12. Due to such discharge of energy through the primary winding II, a high-voltage impulse is induced in the secondary winding 14 of the ignition transformer I2, and this induced high-voltage pulse causes an electrical discharge across the electrodes of the spark plug IS. The electrical discharge results in ignition of the compressed fuelair mixture within the cylinder of the internal combustion engine, shortly prior to the upper dead center position of the crank head. Under normal conditions, the crank head overshoots the upper dead center position due to its momentum, and the operation of the internal combustion engine is thereby realized in proper fashion. For every further rotation of the magnetic system 1, the ignition process is repeated in the manner described above.

It is possible, however, that while the fuel-air mixture becomes ignited, the piston or crank head does not overshoot the upper dead-center position or point. Under such conditions, the internal combustion engine rotates in the undesired and wrong direction, provided the precautionary measure of the present invention is not taken. This precautionary measure resides in principle on the basis that the ignition capacitor 10 is guarded against forcible discharge in an ignition capacitor, during incorrect rotation of the internal combustion engine, through removal of at least one of the essential electrical parameters at the required instant of time. This instant of time corresponds to that instant at which the control winding 3 has induced within it a control voltage of polarity for switching on or triggering the electronic discharge switch 13.

The preceding precautionary means or step may be realized through corresponding design of the magnetic system I in relation to the control winding 3 which is inductively influenced by the system I. The influencing effect is such that when the magnetic system I moves past the poles l8 and 19 of the ferromagnetic core 17, a positive half wave voltage is induced within the control winding 3. This induced voltage has a minimum control voltage magnitude for turning on the electronic discharge switch 13, and is of positive polarity. When the correct rotational direction of the engine prevails, the peak value of this induced voltage has the minimum value required for turning on the discharge switch 13, whereas the induced voltage is below this required minimum value when the engine rotation is in wrong direction.

One possibility for simplifying the effect of the magnetic system I upon the control winding 3, resides in the feature that the frontal ends of the poles l8 and 19 of the ferromagnetic core 17 are spaced by a variable amount a in the direction of motion, with respect to the magnetic system I. As an example, the control winding 3 is arranged upon the ferromagnetic core I7 so that when the magnetic system 1 moves past the poles l8 and 19 of the ferromagnetic core I7, the negative portion of the voltage wave appears before or prior to the positive half wave portion. Accordingly, in the correct rotation direction of the internal combustion engine, a negative voltage half wave with substantially small amplitude is generated with increase in the magnetic flux. When, on the other hand, the magnetic flux decreases suddenly, a positive half wave voltage with substantially high amplitude is realized. With this high-amplitude voltage, the minimum control voltage value is attained at the control electrode G of the electronic discharge switch 13, and the discharge of the ignition capacitor 10 is initiated. In contrast to this situation, a negative voltage wave with high amplitude results when the magnetic flux suddenly increases while the engine is rotating in the wrong direction. In such incorrect rotation of the engine, however, a positive voltage half wave with substantially low am plitude is realized with decrease in the magnetic flux. This low-amplitude positive voltage does not permit that the minimum control value for the control electrode G of the electronic discharge switch 13 be attained, and hence no discharge of the ignition capacitor 10 becomes initiated. Consequently the rotation of the engine in the incorrect direction is thereby made impossible.

The ignition arrangement of FIG. 2 is analogous in principle to the arrangement of FIG. 1. The circuit elements which operate similarly and have identical functions, have been designated with the same reference numerals. The basic functional operation described in relation to FIG. 1, applies to this FIG. 2 also. The difference of the arrangement of FIG. 2 in comparison with that of FIG. I, resides in the condition that the frontal ends of the poles I8 and I9 of the ferromagnetic core I7 are uniformly or constant spaced from the magnetic system 1. Furthermore, the time interval between the charging of the ignition capacitor 10 and the appearance of a control voltage within the control winding 3, in relation to a predetermined speed of the magnetic system I, is substantially smaller for wrong directions of the engine, than for the correct rotational direction of the engine. For this reason, the ferromagnetic core 4 of the charging coil 2 and the ferromagnetic core I7 of the control winding 3 are spaced by a relatively small angle a, in the direction of motion designated by the arrow p. In the wrong direction of motion, however, a relatively large angular spacing B prevails. A further difference from the arrangement of FIG. I resides in the feature that an auxiliary discharge resistor 20 is provided in conjunction with the ignition capacitor 10. This auxiliary discharge resistor 20 may be in the form of a linear or nonlinear resistor, and may be in the form of a temperature-dependent resistor. In every case, however, the auxiliary discharge resistor 20 is chosen so that the capacitor 10 can discharge after charging with a time constant by which the charge is sufficient for ignition with correct rotation of the engine, at the instant that a control voltage appears within the control winding 3. In the wrong direction of the engine, however, the capacitor charge is insufficient to carry out an ignition process. In conjunction with the resistor 20, it is desirable to provide a regulating arrangement 21 which is designated in the drawing with dashed lines, and which functions in relation to the rotational speed of the engine. The regulating arrangement 2] adjusts the value of the resistor 20, so that the ohmic value of the auxiliary discharge resistor 20 decreases with increase in speed of the engine.

In the simplest case, the regulating arrangement may, for example, be constructed so that the resistor 20 is fixed in the proximity of the center of the magnetic system I, and is in the form of a magnetic-field-dependent resistor such as a field plate. Centrifugal weight in the form of magnets are operated in conjunction with the magnetic system and about the magnetic-dependent resistor. When the rotational speed of the magnetic system 1 thus increases, the magnets associated with the centrifugal weights become further spaced from the resistor 20, and the ohmic value of this resistor thereby decreases.

The ignition arrangement in FIG. 3 is based essentially on the same principle of FIG. I. Identical reference numerals are again assigned to those circuit elements which have the same functional operation and the same purposes. The basic operational description provided in relation to FIG. 1, applies to this arrangement of FIG. 3 also. One difference of the arrangement of FIG. 3 from FIG. I, resides in the condition that the frontal ends of the poles l8 and 19 of the ferromagnetic core 17 are uniformly spaced from the magnetic system I. A further difference resides in the parallel circuit associated with the ignition capacitor 10. This circuit which is connected in parallel with the capacitor 10 consists of a resistor 22 connected in series with a path AK' of an electronic switch 23 which may, for example, be in the form of a thyristor. The resistor 22 functions as a protective resistor. The auxiliary switch 23 is controlled so that when the engine rotates in the wrong direction, so that this switch 23 conducts prior to the conduction of the discharge switch 13, after charging of the ignition capacitor 10. For this purpose, a resistor 24 is connected in series with the control path G-K' of the electronic switch 23. This resistor 24 is, furthermore, connected to an auxiliary winding 25 which becomes influenced by the magnetic system 1 prior to the instant at which the control winding 3 becomes influenced, when the engine rotates in the wrong direction. The auxiliary winding 25 is arranged, for this reason, upon a U-shaped ferromagnetic core 26 which has poles 27 and 28 lying opposite and between the ferromagnetic core 4 of the charging coil 2 and the core 17 of the control winding 3, when taken in the wrong direction of motion of the engine.

Accordingly with an ignition arrangement designed in accordance with FIG. 3, operation of the engine in the wrong direction is impossible, since in such a case the electronic switch 23 conducts, after charging of the ignition capacitor 10, and as a result the ignition capacitor can discharge through this electronic switch 23 when the latter commences to conduct. When the control voltage from the control winding 3 then appears at the control electrode G of the discharge switch 13, the ignition capacitor 10 has no longer any energy available for carrying out the ignition process. When, on the other hand, the engine rotates in the correct direction, the auxiliary switch 23 has no influence or effect upon the ignition process.

The ignition arrangement of FIG. 4 differs from that disclosed in FIG. 3, through the feature that the electronic auxiliary switch 23 is an NPN transistor which is controlled through a magnetic-field-dependent semiconductor element 29 which may be in the form of a field plate. This magneticfield-dependent semiconductor element 29 forms a voltage divider in conjunction with a scaling resistor 30. This voltage divider is, in turn, connected in parallel with the ignition capacitor l0, and has a junction or tap 31 connected to the control electrode G of the electronic auxiliary switch 23. The magnetic-field-dependent semiconductor element 29, furthermore, forms an arrangement with a yoke 32 made of magnetic material and which has

poles

33 and 34 directed toward the magnetic system I. In the wrong direction of rotation of the engine, these

poles

33 and 34 lie between the ferromagnetic core 4 of the charging coil 2, and the core 17 of the control coil 3 associated with the magnetic system 1.

With the embodiment of FIG. 4, the electronic auxiliary switch 23 also becomes conducting when the engine rotates in the wrong direction. In this manner, the ignition capacitor 10 can discharge before the induced AC control voltage within the control winding 3 reaches the control electrode G of the electronic discharge switch 13.

The turning on of the electronic auxiliary switch 23 results from the condition that the control path G-l(' which is normally of low ohmic resistance value, is made to have a very large resistance value, as a result of the inductive effect of the magnetic system 1 upon the magnetic-fieId-dependent semiconductor element 29 which is connected in parallel with this control path G'-K' of the auxiliary switch 23. In view of the high resistance imposed upon the path G'-K, the potential at the junction of tap 31 of the

voltage divider

29, 30, becomes positive, and the circuit path A'K' becomes thereby conducting and provides simple discharge for the ignition capacitor 10. When, on the other hand, the engine rotates in the proper or correct direction, the auxiliary switch 23 has, in this embodiment, also no effect or influence upon the ignition process.

The ignition arrangement of FIG. 5 is equivalent, in principle, to the arrangement shown in FIG. 1. Accordingly, identical reference numerals are assigned to the circuit elements which have the same functional operation and the same task from the circuit point of view. The description provided with the basic functional operation for FIG. 1, furthermore, applies here, to FIG. 5, also. One difference of this embodiment compared to that of FIG. 1, resides in the condition that the

poles

18 and 19 of the ferromagnetic core 17 are uniformly spaced from the magnetic system 1. Aside from this, the electronic" conducts positively directed current, and which is connected to the control electrode G of the discharge switch 13. The auxiliary winding 35 is mounted upon a U-shaped ferromagnetic core 37 which has two

poles

38 and 39 directed toward the magnetic system I. The ferromagnetic core 37 is situated somewhat beneath the dead center of the piston head.

When the engine rotates in the wrong direction, the auxiliary winding 35 becomes inductively influenced by the magnetic system 1, prior to the control winding 3 upon charging of the ignition capacitor 10. I

With an ignition arrangement designed in accordance with FIG. 5, it is also not possible to drive the engine in the wrong direction. This results from the condition that the auxiliary winding 35 turns on the discharge switch 13 so that the latter becomes conducting and thereby initiates the ignition process before the fuel-air mixture within the cylinder becomes compressed. Accordingly, when the induced voltage within the control winding 3 reaches the control electrode G of the discharge switch I3 at the instant of time when the fuel-air mixture is compressed, no further energy is available from the ignition capacitor I0 to carry out the ignition process. When, however, the internal combustion engine rotates in the correct or proper direction, the auxiliary winding 35 has no effect in the control of the discharge switch 13, since the ignition capacitor 10 was already discharged beforehand in operating under proper conditions.

The ignition arrangement disclosed in FIG. 6 resides upon the same principle which applies to FIG. 1. The circuit ele* ments which perform the same functional operation and have the same purposes and tasks in both of these embodiments, are designated with identical reference numerals. The basic description for the functional operation of FIG. 1 also applies to the arrangement of FIG. 6. The difference between the em-' bodiment of FIG. 6 and that of FIG. 1 resides in the feature that a control voltage is generated for switching or turning on the electronic discharge switch 13, through corresponding inductive effect upon the control winding 3 for both compressed fuel-air mixture, as well as fuel-air mixture which has not, as yet, been compressed. This situation results from the condition that in the proper or correct direction of rotation of the engine, and for the compressed mixture, the inductive influence of the control winding 3 is applied to the charging process of the ignition capacitor 10. In the wrong direction of rotation of the engine, in which case the mixture has not yet been compressed, the control winding 3 also has an inductive influence upon the charging process of the ignition capacitor 10.

The preceding arrangement is advantageously realized by mounting the control winding 3 upon a permanent magnet 40 which has a yoke 41. Two magnetic members 42 and 43 made of magnetically conducting material are movable past the yoke 41 through the action of the engine. The magnetic member 42 is used to close the magnetic path over the yoke 41 when the mixture has been compressed. The member 43, on the other hand, is used for this purpose of closing the magnetic path over the yoke 41, when the mixture has not, as yet, been compressed. The magnetic members 42 and 43 are mounted, for this purpose, onto the magnetic system 1.

The constructional design of the magnetic members 42 and 43 in conjunction with the magnetic system 1 is such that the path of motion of the inductively functioning parts 44 of the members 42 and 43, occurs only past the frontal ends of the yoke 41 carrying the control winding 3. At the same time, the path of motion of the poles N and S of the magnetic system 1 are brought past only the frontal ends of the poles 5, 6 and 7 of the ferromagnetic core 4 carrying the charging coil 2. In the example of FIG. 7, the inductively operating parts 44 of the magnetic members 42 and 43 are, for this purpose, raised from the plane of the yoke 41 carrying the control winding 3, and are preferably magnetically isolated therefrom. The magnetic poles N and S of the magnetic system 1 move relative to the ferromagnetic core 4 carrying the charging coil 2. As a result, the poles N and S of the magnetic system 1 do not exercise any undesired effect upon the control winding 3 when moving past the yoke 41. Furthermore, the ferromagnetic core with its charging coil 2 does not interfere with the motion of the magnetic members 42 and 43. it is also possible to achieve this situation by arranging the magnetic members 42 and 43 on the frontal edge of the magnetic system 1 with smaller spacing from the center point, than the poles N and S of the magnetic system 1. In this case, the yoke 41 carrying the control winding 3 has its pole ends directed toward the path of motion of the magnetic members 42 and 43.

In the operation of the embodiments of FIGS. 6 and 7, assume that the internal combustion engine rotates in the correct direction, and the magnetic system rotates also in the direction of the arrow designated p. The ignition capacitor 10 becomes thereby charged when the poles N and S move past the ferromagnetic core 4 carrying the charging coil 2. The magnetic member 42 with its inductively operating part 44 consequently moves past the yoke 41, whereby the flux emanating from the magnet 40 and passing through the yoke 41 becomes varied and a control voltage is induced within the control winding 3. This control voltage then turns on the discharge switch 13 so that the latter becomes conducting. With the discharge of the ignition capacitor 10 through the primary winding 11 of the ignition transformer 12, a high-voltage pulse appears within the secondary winding 14. This highvoltage pulse produces a spark across the electrodes of the spark plug 15. The occurrence of such a spark takes place at the instant of time that the fuel-air mixture is substantially maximum compressed. in an internal combustion engine of conventional design, the pistonhead would be located, under these conditions, shortly before the upper dead center position. lf, thereupon, the magnetic member 43 moves past the yoke 41, a control voltage is generated for turning on the discharge switch 13. Such control voltage, however, remains ineffective because at that instant of time that this control voltage is generated, the ignition capacitor 10 has not again become charged. During the operation of the internal combustion engine, thereby, these ignition processes are repeated in the manner described above.

If, now, the engine rotates in the wrong direction, then the magnetic system 1 rotates in the direction opposite to that designated by the arrow p. After charging of the ignition capacitor 10, in this case, the magnetic member 43 moves past the yoke 41 carrying the control winding 3. As a result, the discharge switch 13 is transferred to conducting state at that instant of time, and the ignition spark is produced in the manner described above.

The position of the magnetic member 43 on the magnetic system 1 is established, for example, at the lower dead center position of the pistonhead within the cylinder of the engine. ln this position, no effective ignition of the fuel-air mixture can take place. As a result, the operation of the engine in the wrong direction is inhibited. As a result of the remaining kinetic energy of the pistonhead, additional fuel-air mixture within the cylinder becomes compressed. Furthermore, a control voltage suitable for turning on the discharge switch 13 becomes induced, at the correct instant of time, within the control winding 3, as a result of the motion of the magnetic member 42 past the yoke or core 41. However, no ignition of the mixture within the cylinder can take place, because the ignition capacitor 10 has already been discharged. Any further operation of the engine in the wrong direction is, thereby, avoided.

The operation as described above, also prevails when the inductive parts or members 44 are in the form of magnets, in place of the magnet 40 in the core 41.

In the above-described embodiments, only one single spark plug is contained within the secondary winding of the ignition transformer 12. it is, however, within the scope of the present invention, that the secondary winding circuit contains a plurality of spark plugs. With a number of such spark plugs to be serviced, the ignition pulse can be transmitted to the spark plugs in proper sequence through a conventional ignition distributor. The magnetic system 1 can, under these conditions be driven at the correspondingly correct angular velocity, through a linkage arrangement. At the same time, the proper speed for the magnetic system 1 can be obtained through its inherent design.

It is further considered to be within the scope and frame of the present invention, when the magnetic system 1 is maintained stationary, and the engine drives or applies motion to the charging coil 2, the control winding 3, the auxiliary winding 25, the coil 35, as well as the magnetic-field-dependent semiconductor element 29.

Finally, the

ferromagnetic cores

4, 17, 26, 32, 37 and 41 can also be moved through the engine and be set into rotation by being arranged upon a pot-shaped magnetic system, whereby they are constructed in the form of fibrous annatures.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions differing from the types described above.

While the invention has been illustrated and described as embodied in an ignition arrangement for internal combustion engines, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims.

We claim:

1. An ignition arrangement for an internal combustion engine, comprising, in combination, ignition capacitor means; charging coil means connected to said ignition capacitor means to charge the latter; controlled electronic switch means for discharging said ignition capacitor means; ignition transformer means with primary winding connected in series with said switch means, said seriesconnected primary winding and switch means being connected to said capacitor means so that the latter can discharge through said primary winding when said switch means conducts; spark plug means connected to the secondary winding of said transformer; control coil means for applying a brief control voltage of predetermined polarity to said controlled electronic switch means so as to render the latter conductive when the engine is adjacent top dead center; whereby said capacitor means can discharge through said primary winding of said ignition transformer means; magnetic means for periodically inducing in said charging coil means a charging current and for briefly inducing in said control means said control voltage when the engine is adjacent top dead center, said charging current occurring before said control voltage when the engine is turning in a predetermined direction; and means, effective when the engine rotates opposite to said predetermined direction, for at least partly short circuiting said capacitor means after the latter is charged but before said switch means is rendered conductive when the engine is adjacent top dead center so that said capacitor means is sufficiently discharged when said switch means is rendered conductive when the engine is adjacent top dead center so as to prevent ignition.

2. The ignition arrangement for an internal combustion engine as defined in claim 1, wherein said magnetic means is driven by said engine relative to said charging coil means for inducing said charging voltage therein.

3. The ignition arrangement for an internal combustion engine as defined in claim 2 wherein said magnetic means is driven additionally relative to said control coil means for inducing said control voltage within said control coil means.

4. The ignition arrangement for an internal combustion en gine as defined in claim 3, wherein said means for at least partly short circuiting said capacitor means includes discharge resistor means shunted across said ignition capacitor means for discharging said ignition capacitor means with a predetermined time constant, the time interval between charging of said ignition capacitor means and inducing said control voltage within said control coil means being substantially smaller when the engine rotates in said predetermined direction than when the engine rotates opposite to said predetermined direction, said ignition capacitor means being substantially fully charged at the instant of inducing said control voltage when the engine rotates in said predetermined direction, said ignition capacitor means being substantially discharged at the instant of inducing said control voltage when the engine rotates opposite to said predetermined direction, whereby the charge of said ignition capacitor means is insufficient for ignition when the engine rotates opposite to said predetermined direction.

5. The ignition arrangement for an internal combustion engine as defined in claim I, wherein said means for at least partly short circuiting said capacitor means include auxiliary electronic switch connected in parallel with said ignition capacitor means for discharging said ignition capacitor means prior to actuation of said controlled electronic switch means by said induced control voltage when said engine rotates opposite to said predetennined direction.

6. The ignition arrangement for an internal combustion engine as defined in claim 5, including protective resistor means connected in series with said auxiliary electronic switch means.

7. The ignition arrangement for internal combustion engine as defined in claim 5, including auxiliary coil means connected to said auxiliary electronic switch means for applying an actuating voltage to said auxiliary electronic switch means, and wherein said magnetic means moves relative to said auxiliary coil means, charging coil means, and control coil means for inducing voltages within these three coil means, said magnetic means inducing a voltage within said auxiliary coil means prior to inducing the voltage within said control coil means when said engine rotates opposite to said predetermined direction.

8. The ignition arrangement for internal combustion engine as defined in claim 5, wherein said maGnetic means moves relative to said charging coil means and said control coil means for inducing said voltages within these two coil means, and further including magnetically dependent semiconductor means positioned to be passed by and influenced by said magnetic means; scaling resistor means connected in series with said magnetically dependent semiconductor means for forming with said semiconductor means a voltage divider connected in parallel with said ignition capacitor means, said magnetic means being driven relative to said magnetically dependent semiconductor means; and means for connecting the voltage junction between said scaling resistor means and said magnetically dependent semiconductor means to said auxiliary electronic switch means so as to render the latter conductive when said magnetic means passes thereby, said magnetically dependent semiconductor means being influenced by magnetic means prior to said control coil means after charging of said ignition capacitor means when the engine rotates opposite to said predetermined direction.

9. The ignition arrangement for an internal combustion engine as defined in claim 8 including a magnetic core magnetically coupled with said magnetic-field-dependent semiconductor means, said core having poles directed toward said magnetic means.

10. The ignition arrangement for an internal combustion engine as defined in claim 8 wherein said auxiliary electronic switch means comprises a semiconductor element switchable with positive control voltage.

11. The ignition arrangement for an internal combustion engine as defined in claim 3, wherein said means for at least partly short circuiting said capacitor means includes auxiliary coll means connected to said electronic switch means, and

said magnetic means moves relative to said auxiliary coil means so that said auxiliary coil means applies a voltage to said controlled electronic switch means prior to said control coil means when said internal combustion engine rotates opposite to said predetermined direction and the fuel-air mixture within the engine is substantially uncompressed.

12. The ignition arrangement for an internal combustion engine as defined in claim 11, wherein said means for at least partly short circuiting said capacitor means includes diode means connected to said controlled electronic switch means for transmitting only positive control current to the latter.

13. The ignition arrangement for internal combustion engine as defined in claim 1, wherein said control voltage is applied to said controlled electronic switch means at the instant that the air-fuel mixture within the engine is compressed and the engine rotates in said predetermined direction, said control voltage being applied to said controlled electronic switch means before said mixture is compressed when the engine rotates opposite to said predetermined direction.

14. The ignition arrangement for an internal combustion engine as defined in claim 10, including core means for said control coil means and enclosing at least one magnet; at least two members of magnetizable material movable relative to said core so that one of said magnetizable members closes the magnetic circuit of said core when said mixture is compressed and the other one of said magnetizable members closes the magnetic circuit of said core before said mixture is compressed.

15. The ignition arrangement for an internal combustion engine as defined in claim 14 wherein said magnetizable members are integrally mounted with said magnetic means.

16. The ignition arrangement for an internal combustion engine as defined in claim 15 including further core means for carrying said charging coil, said magnetizable members moving only past the poles of said core carrying said control winding and the poles of said magnetic means moving only past the poles of said further core carrying said charging coil means.

Claims

1. An ignition arrangement for an internal combustion engine, comprising, in combination, ignition capacitor means; charging coil means connected to said ignition capacitor means to charge the latter; controlled electronic switch means for discharging said ignition capacitor means; ignition transformer means with primary winding connected in series with said switch means, said series-connected primary winding and switch means being connected to said capacitor means so that the latter can discharge through said primary winding when said switch means conducts; spark plug means connected to the secondary winding of said transformer; control coil means for applying a brief control voltage of predetermined polarity to said controlled electronic switch means so as to render the latter conductive when the engine is adjacent top dead center; whereby said capacitor means can discharge through said primary winding of said ignition transformer means; magnetic means for periodically inducing in said charging coil means a charging current and for briefly inducing in said control means said control voltage when the engine is adjacent top dead center, said charging current occurring before said control voltage when the engine is turning in a predetermined direction; and means, effective when the engine rotates opposite to said predetermined direction, for at least partly short circuiting said capacitor means after the latter is charged but before said switch means is rendered conductive when the engine is adjacent top dead center so that said capacitor means is sufficiently discharged when said switch means is rendered conductive when the engine is adjacent top dead center so as to prevent ignition.

4. The ignition arrangement for an internal combustion engine as defined in claim 3, wherein said means for at least partly short circuiting said capacitor means includes discharge resistor means shunted across said ignition capacitor means for discharging said ignition capacitor means with a predetermined time constant, the time interval between charging of said ignition capacitor means and inducing said control voltage within said control coil means being substantially smaller when the engine rotates in said predetermined direction than when the engine rotates opposite to said predetermined direction, said ignition capacitor means being substantially fully charged at the instant of inducing said control voltage when the engine rotates in said predetermined direction, said ignition capacitor means being substantially discharged at the instant of inducing said control voltage when the engine rotates opposite to said predetermined direction, whereby the cHarge of said ignition capacitor means is insufficient for ignition when the engine rotates opposite to said predetermined direction.

5. The ignition arrangement for an internal combustion engine as defined in claim 1, wherein said means for at least partly short circuiting said capacitor means include auxiliary electronic switch connected in parallel with said ignition capacitor means for discharging said ignition capacitor means prior to actuation of said controlled electronic switch means by said induced control voltage when said engine rotates opposite to said predetermined direction.

11. The ignition arrangement for an internal combustion engine as defined in claim 3, wherein said means for at least partly short circuiting said capacitor means includes auxiliary coil means connected to said electronic switch means, and said magnetic means moves relative to said auxiliary coil means so that said auxiliary coil means applies a voltage to said controlled electronic switch means prior to said control coil means when said internal combustion engine rotates opposite to said predetermined direction and the fuel-air mixture within the engine is substantially uncompressed.