SPARK DURATION CONTROL DEVICE AND METHOD IN AN IC ENGINE
FIELD OF THE INVENTION
[0001] The present invention relates to spark ignition engines and more particularly towards improving the combustion characteristics of fuel in the spark ignition engines.
DESCRiPTION OF THE BACKGROUND ART
[0002] To achieve better fuel efficiency nowadays the fuel - air mixture fed to the combustion chamber is to be made leaner. In normal conditions, the air to fuel ratio is 14:1(AIR: PETROL), As the amount of fuel in the mixture is made lesser, it becomes leaner. The leaner the fuel becomes, it poses difficulty in ignition. The CDI gives the spark energy (which is large in amount than is necessary') in kind of a spike. The high vohage current from the high voltage coils is not completely applied to the air-fuel mixture, the ignition is not effective. Moreover, carbon debris will accumulate in the spark plug. As a result, lifetime of the electric or electronic device is shortened. Furthermore, a great amount of waste gas due to incomplete combu.stion will pollute environment. To counter the problem of fuel efficiency in the leaner mixture various improvements have been made til! date bul none of them seem to have addressed the above listed problems to a larger extent.
[0003] Among one of the developments which is disclosed in US patent 7036494 wherein an ignition enhancement device for enhancing ignition efficiency of car engine which is installed between a high vollagc wire and a spark plug. The ignition enhancement device has a capacitor. Two sides of the capacitor being are connected to two metal conductive rods. An insulating sleeve encloses the capacitor: and two sides of the insulating sleeve are formed with two insertion holes. An outer wall of each of the two sides of the insulting sleeve has an annular slot: and two ends of the capacitor being covered by waterproof rubbers. When the engine is actuated, the capacitor serves to store the current from the high voltage wire. When the capacitor saturates, electrons are charged to the spark plug simultaneously so as to enlarge the current to have the elTcct of

enhancing the discharge of the current. Thus, the ignition can be enhanced and the fuel is burnt completely.
[0004] However being a good attempt to solve the above-discussed problems, the US patent suffers from various drawbacks, like the said device would cause a break in the high voltage ignition cable for its insertion leading to increase in the radio interference. Another problem that may occur would be that the scries capacitance of the device would increase the 'Quality factor" of ignition coil secondary circuit, causing a large voltage build up in the device, which would eventually discharged to (he spark plug can cause extra heat build up in the combustion chamber.
[0005] Such a situation is however objectionable and accordingly demands an improvement. Thus there is need to provide a mechanism that solves at least one of the above listed drawbacks.
SUMMARY
[0006] Accordingly it is an object of the present invention to enhance the spark occurrence of the spark plug.
[0007] Presently, a system to enhance the spark that helps in improving the combustion characteristics of a Spark Ignited (SI) Internal Combustion (IC) Engine is disclosed herein. The present SI engines utilizes Capacitor Discharge Ignition (CDI) system in which a capacitor is charged to about 400V and made to discharge at the closure of a switch to the ignition coil (a step up coil), all the energy stored instantaneously for a very short duration gets transferred to a spark cable. Further to this system a capacitor along with an inductor is formed and coupled to the CDI system via a spark cable. This system allows even leaner mixture to burn completely thereby allowing improvement in fuel efficiency of the vehicle and lesser emission,
[0008] Accordingly therefore one embodiment of the present invention discloses a system capable of being configured with a spark ignition (SO engine for improving the combustion characteristics thereof The system comprising of a capacitor discharge ignition circuit that is configured with a step up coil for discharging instanlaneous spark energy to the step up coil. A spark plug is further utilized for conveying instantaneous

spark energy produced from the capacitor discharge ignition circuit and the step up coil to the spark plug. Additionally, a mechanism for storing excess amount of the instantaneous spark energy and to redistribute the same is configured to the spark cable and the spark plug, whereby excess amount of the instantaneous spark energy gets stored in the mechanism and redistributed to the spark plug to prolong the duration of spark occurrence thereby improving the combustion of fuel in the SI engines.
[0009] According to one embodiment of the present invention, the mechanism for storing and redistribution of the excess amount of spark energy comprises of a capacitor connected in series to an inductor. The inductor is connected to electrodes of the spark plug in series.
[0010] The inductor, capacitor formed by the winding - ignition cable and spark gap form kind of resonant circuit, which cause damped oscillations for an elongated interval leading to better combustion of leaner air-fuel mixtures.
[0011] Further, the capacitor gets charged to the peak voltage of the ignition coil and produces peaking oscillations of the excess spark energy that is further received by the spark plug thereby prolonging the spark duration.
[0012] According to one embodiment of the present invention an insulated flexi-house envelops the spark cable. Alternatively a plurality of spacers is also placed inside the flexi-house to maintain the spark cable in axial position.
[0013] Other objects, features and advantages of the invention will be apparent from the drawings, and from the detailed description that follows below.
BRIEF DESCRIPTION OF THE FIGURES
[0014] Reference wiii be made to embodiments of the invention, examples of which may be illustrated in the accompanying figures. These figures are intended to be illustrative, not limiting. Although the invention is generally described in the context of these embodiments, it should be understood that it is not intended to limit the scope of the invention to these particular embodiments,
[0015] Fig 1 illustrates the perspective view of the system according to an embodiment of the present invention.

[0016] Fig 2 shows the electrical equivalent diagram of the ignition coil and Ihe mechanism comprising an inductor and capacitor of the embodiment as shown in Fig. 1
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] It must be noted that normally to achieve better fuel efficiency the fuel - air mixture fed to the combustion chamber is to be made leaner In normal conditions, the air to fuel stoichiometric ratio is 14:1{AIR: PETROL) i.e.. for burning one part of fuel 14 parts of air is needed. In the foregoing description for the purpose of having batter and clear understanding fuel would be referred to as petrol. Nowadays since as the amount of fuel in the mixture is made lesser, it becomes leaner. As leaner the fuel becomes, it poses further difficulty in ignition and combustion which in totality creates further problems like improper burning of fuel, more pollution production etc. The preferred embodiments of the present invention as we go through the foregoing description attempts to provide a clear understanding as in how the working of the various embodiments overcomes these problems.
[0018] The following description is set forth for purpose of explanation in order to provide an understanding of the invention. However, it is apparent that one skilled in the art will recognize that embodiments of the present invention, some of which are described below, may be incorporated into a number of different computing systems and devices. The embodiments of the present invention may be present in hardware, software or firmware. Structures shown below in the diagram are illustrative of exemplary embodiments of the invention and are meant to avoid obscuring the invention. Furthermore, arrangements of components within the figures arc not intended to be limited,
[0019] Reference in the specification to "'one embodiment", "in one embodiment" or "an embodiment" etc. means that a particular feature, structure, characteristic, or function described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment,
[0020] Now referring to Fig 1 that explains one of the embodiments of the present invention, a system capable of being configured with a spark ignition (SI) engine (not

shown) for improving the combustion characteristics thereof, the system comprising a capacitor discharge ignition circuit 10 configured with a step up coil for discharging instantaneous spark energy to the step up coil 12. A spark plug 16 for conveying instantaneous spark energy, the spark plug 16 coupled with combination of the capacitor discharge ignition circuit 10 and (he step up coil 12 via a spark cable. A mechanism 14 for storing excess amount of the instantaneous spark energy and to redistribute the same, the mechanism 14 is configured to the spark cable and the spark plug 16. whereby excess amount of the instantaneous spark energy gets stored in the mechanism Hand redistributed to the spark plug 16 to prolong the duration of spark occurrence thereby improving the combustion of fuel in the St engines.
[0021] The capacitor discharge ignition circuit 10 and the ignition coil produces the necessary current in the form of spark energy and sends to the spark plug 16 for producing the spark. In the foregoing description for the purpose of clarification capacitor discharge ignition circuit 10 would be hereinafter referred to as CD] circuil 10 and the stepped up current produced by the ignition coil would be referred to as spark energy-
[0022] The CDI circuit 10 gives spike of voltage that is of the order of 400V to the ignition coil to step up the voltage to level required by the fuel mixture at the peak of compression stroke in the SI engine. In the system ignition coil that is actually a step up transformer receives the spark energy produced by the CDI circuit 10. the voltage of the spark energy after passing through the ignition coil increases 12K.V upto 14KV, Actually. a switch is configured in between the CDI circuit 10 and the Ignition coil, which upon closure dumps the all of the spark energy into the Ignition coil. The time of the closure is predetermined and is controlled by the timing circuit. This spark energy upon requirement and as programmed is transferred instantaneously to the spark plug 16 which thereafter produces the spark and shells out the necessany energy required for combustion of the fuel in the piston cylinder arrangement. As the piston reaches towards the compression cycle in the cylinder, the spark energy is shelled out to burn the fuel and this process continues for each of the cycles of the engine.
[0023] Once the current is produced it is received by the ignition coil acting like a step up transformer, this is actually done with the help of inductor 21 of the ignition coil. As the

produced charge from the GDI circuit 10 passes through the inductor 21 the amplitude of the oscillation increases that further results in increasing the overall voltage of the spark energy. Under normal condition when there is no mechanism 14 between the spark cable and the spark plug 16, at a particular time nearly all the spark energy (without considering the various losses into account) is instantaneously dumped into the spark plug 16 that produces the spark. Due to this the Ignition coil shells out more energy than what is required and as discussed in the prior art section these has various implications. In order to counter the same, a mechanism 14 has been developed and configured in between the spark cable and the spark plug 16,
[0024] According to another embodiment of the present invention the mechanism 14 for storing and redistribution of energy comprises of a capacitor 20 and an inductor 22 the circuit of which is connected in series, the combination of capacitor 20 and the inductor 22 stores the excess amount of energy. It is to be understood that function of the inductor 22 is to produce oscillations whose frequency is pretty high but they are of smaller value and only of few Henry. Alternatively a plurality of capacitors and inductors may also be included into the mechanism 14 depending on the need and capacity of the operation.
[0025] The spark plug 16 now absorbs an amount of energy that is necessary at the instant of occurrence of signal from CD] unit. Further, the excess amounl of slored energy is redistributed over time to the spark plug 16 thercby prolonging the duration of the spark in the spark plug 16. It is to be considered that in all the above operation the spark energy which is generated from the ignition coil actually remains the same like what it was produced in the absence of the mechanism, but actually the energy gets distributed over time to the spark plug 16 thereby taking into account the prolonging of the produced spark in the spark plug 16,
[0026] Working of the mechanism 14 is better illustrated by understanding the embodiment of the invention from the perspective of combining Fig J and Fig 2 and then analyzing it. In the combustion chamber, the initial spark with out the mechanism 14 would not have ignited all the fuel due to the lean-ness and there would have been still some fuel vapor left for combustion. Amplitude of oscillations produced due to the another inductor present in the ignition coil from may still have reached the spark helping

in producing the required spark in the spark plug 16 but there would ha\e been a strong possibility that the amplitude might have died soon thereby not producing the spark to the required extent for providing combustion to the air fuel mixture.
[0027] The excess amount of energy, which is being stored in the capacitor 20, actually makes the spark to occur again and therefore in this process prolongs the duration of the spark in the combustion process. The inductor 22 that is connected in series with the capacitor 20 receives the excess energy and thereafter conyerts the same into peaking oscillations. The peaking oscillations occur at the resonant frequency of L -C- R is the resistance offered between the spark electrodes 24 gap by the fuel mixture. The resistance between the electrodes 24 of spark plug 16 brings down the amplitude of oscillations and therefore the oscillations die out well before the next cycle of the S! engine startts and this continues throughout all of the cycles. For each of the compression stroke of the SI engine as the excess energy from the capacitor 2(1 decreases amplitude of the sequential spark goes on diminishing. Due to this the spark completely dies out before the beginning of the next compression stroke and the whole procedure is again and again repeated for all of the cycles. With the value of capacitor 20 and inductor 22 judiciously chosen, the spark repetition will not extend till next compression stroke even at high RPM ranges of the SI engine.
[0028] After going through the above embodiments it would be clearly understood by any person skilled in the art the embodiments described herein provides better combustion of the air fuel mixture. .Also for a given amount of power lesser fuel is required to be burnt and hence therefore better is the efficiency (upto 33% improvement of fuel efficiency).
[0029] According to one embodiment of the present invention as shown in Fig 1 an insulated flexi-house 18 may also envelop the spark cable. Altemativelv a plurality of spacers is also placed inside the flexi-house 18 to maintain the spark cable in axial position.
[0030] In one embodiment of the present invention also shown in Fig 1 a neon lamp (not shown) is added to the mechanism 14 thereby ensuring easy diagnosis of the presence of spark energy stored therein.

[0031] The application of the mechanism 14 in its present form is simplest to install in any kind of application like motorbikes, autorikshaws. cars, portable generators and Petrol/kerosene/LPG engines used in irrigation purpose. It is simplest lo install by the way that any person can pull the ignition cable out from the Spark plug 16 and slide the device over the cable and place the cable back in original position. A value addition lo the product can be in the form of a spark indicator, which can work without additional external energy source.
[0032] The foregoing description of the invention has been described for purposes of clarity and understanding. It is not intended to limit the invention to the precise form disclosed. Various modifications may be possible within the scope and equivalence of the appended claims.

We Claim:
i. A system capable of being configured with a spark ignition (SI) engine for improving the combustion characteristics thereof, the system comprising: a capacitor discharge ignition circuit configured with a step up coil for discharging instantaneous spark energy to the step up coil;
a spark plung for conveying instantaneous spark energy, the spark plug coupled with combination of the capacitor discharge ignition circuit and the step up coil via a spark cable; and
a mechanism for storing excess amount of the instantaneous spark energy and to redistribute the same, the mechanism is configured to the spark cable and the spark piug,
wherein excess amount of the instantaneous spark energy gels stored in the mechanism and redistributed to the spark plug to prolong the duration of spark occurrence thereby improving the combustion of fuel in the SI engines
2. The system according to claim 1. wherein the mechanism for storing and redistribution of the excess amount of spark energy comprises of a capacitor connected in series to an inductor.
3. The system according to claim 2, wherein the inductor is connected to electrodes of the spark plug (please give your comments) in series.
4. The system according to claim 2. wherein the capacitor gets charged to the peak voltage of the ignition coil.

5. The system according to claim 2, wherein the inductor produces peaking
oscillations of the excess spark energy which is further received by the spark plug
thereby prolonging the spark duration.
6. The system according to claim 1, wherein a switch is configured with the
capacitor discharge ignition circuit and the step up coil.
7. The system according to claim 1, wherein an insulated flexi-house envelops the
spark cable.
8. The system according to claim 7, wherein a plurality of spacers are placed inside
the flexi-house to maintain the spark cable in axial position.
9. The system according to claim 1, wherein a neon lamp is added to the mechanism
thereby ensuring easy diagnosis of the presence of spark energy stored therein,
10. The system according to claim I, wherein the engine is an internal combustion
(!C) engine.