FIELD OF INVENTION
This invention relates to an improved six stroke internal combustion (IC) engine. Particularly this invention relates to an improvement in or modification of the invention claimed in the specification of the main patent application number, “3238/DEL/2011” filed on 15th November, 2011 for a “six stroke IC engine”.
BACKGROUND OF INVENTION
The six stroke internal combustion engine disclosed in the main patent application no. 3238/DEL/2011 comprises a piston adapted to be disposed in a cylinder such that to be moved up and down upon burning of fuel in the cylinder. Cams of a special shapes are provided to operate an inlet valve and an outlet valve such that to provide six strokes in one combustion wherein during fourth stroke outlet vale is opened fully for full time and during fifth stroke the outlet valve remains open partially for some time such that to get back a little amount of exhaust gases which facilitate fifth stroke and exhaustion of the residual burnt gases completely from the cylinder during sixth stroke keeping outlet valve opened completely during sixth stroke.
A six stroke engine has been disclosed in the US patent no. 4917054, which comprising six strokes for the admission of air. The first compression accompanied or followed by a possible cooling. A second compression followed by combustion. The first expansion producing a usable work and the second expansion producing a usable work and finally the discharge of the combustion gases. In this engine the
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combustion is either with spark-ignition or with auto ignition and will include preferably a multiple of five non-uniform cylinders and will have an energy efficiency of up to 30 % higher than that of four stroke IC engine.
A dual six stroke IC engine is disclosed in the US patent no. 7143725 B1. The engine comprises a turbo and a cooling cylinder to compress cool air onto the engine head to reduce engine temperature. The invention generally reduces the size and manufacture cost of the cooling equipments such as radiator and intercooler by cooling the power cylinder from within. Additionally this invention slightly increases fuel efficiency and reduces exhaust temperature.
There are disadvantages associated with the prior art. One of the disadvantages is that the engine do not work as efficiently as it should work.
Another disadvantage associated with the prior art is that the engine does not produce sufficient power as required to run the vehicle.
Yet another disadvantage associated with prior art is that the engine does not work as per euro standards without exhaust air filter effectively.
Still another disadvantage associated with prior art is that for particular amount of power generation, more heat is produced as it is not dissipated fully in the atmosphere and thus causes heating of the engine i.e. cylinder body.
A further disadvantage associated with prior art is that the life of the engine is reduced because of excessive generation of heat.
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Another disadvantage associated with prior art is that mileage of the known engine is low because of leftover burnt gases in the cylinder as it mixes with the fresh fuel intake.
OBJECS OF THE INVENTION
Therefore, an object of the present invention is to provide an improved six stroke IC engine which obviates the disadvantages associated with the prior art.
Another object of the present invention is to provide an improved six stroke IC engine which work efficiently at the minimum fuel consumption.
Yet another object of the present invention is to provide an improved six stroke IC engine which sufficient power and provides more mileage, that is, the power of the engine is increased and also mileage of the engine has been increased with the same strokes, that is, six strokes.
Still another object of the present invention is to provide an improved six stroke IC engine capable to work as per euro standards for engine without using any air filter and thus does not pollute the environment.
A further object of the present invention is to provide an improved six stroke IC engine to produces optimum power by adjusting the timing of opening and closing of the inlet and outlet valves as per the requirement.
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STATE MENT OF THE INVENTION
According to this invention there is provided a six stroke IC engine comprising a piston adapted to be disposed in a cylinder such that to be moved up and down upon burning of fuel in the cylinder, inlet and outlet valve opening cams and rocker of a special shapes being provided to operate an inlet valve and an outlet valve such that to provide six strokes in one combustion wherein during fourth stroke outlet vale is opened fully for full time and during fifth stroke the outlet valve remains open partially for some time such that to get back a little amount of exhaust gases and hold it to facilitate fifth stroke and exhaustion of the residual burnt gases completely from the cylinder during sixth stroke keeping outlet valve opened completely during sixth stroke.
BRIEF DESCRIPTION OF THE DRAWINGS
The improved six stroke IC engine according to a preferred embodiment is herein described and illustrated in the accompanying drawings wherein;
Figures 1A & 1B – illustrates sectional view of piston and cylinder assembly with inlet and outlet cams of the present invention,
Figures 2A & 2B – illustrates parts of inlet and outlet cams,
Figure 3 – illustrates shape of the inlet cam,
Figure 4 – illustrates shape of the outlet cam,
Figures 5A & 5B – illustrates sectional view of the rocker of the present invention.
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DETAILED DESCRIPTION OF THE INVENTION
An improved six stroke internal engine is herein described with numerous specific details so as to provide a complete understanding of the invention. However these specific details are exemplary details and should not be treated as the limitation to the scope of the invention. The invention may be performed with slight modifications.
Referring to the drawings particularly figures 1A and 1B, a piston 1 is accommodated into cylinder 2 such that to be moved up and down upon burning of the fuel in the cylinder 2. The piston 1 is connected to the crank shaft (not shown) through a connecting rod (not shown) such that provide rotational movement to the crank shaft. When the piston 1 moves down the inlet valve 3 is opened due to the movement of a rocker 4. The rocker 4 is operated by a special shaped cam 5 and thus admitting intake of the air fuel mixture, in case of a petrol engine, or only air in case of diesel engine. This is obtained by various shapes of cam 5 and the rocker arm 4. During the second stroke, piston 1 moves from down position to the up position in the cylinder and inlet valve 3 and an outlet valve 6 remains closed. During this stroke the air fuel is compressed constituting a compression stroke. In case of petrol engine, the compressed air fuel mixture is ignited with the help of a spark plug (not shown) at the end of the second / compression stroke. And in case of a diesel engine, diesel fuel in atomized form is injected at the end of the second / compression stroke and ignited due to high temperature and pressure automatically to facilitate combustion of fuel mixture. Due to the combustion of fuel mixture inside the cylinder 2 a high pressure of the gases is generated which pushes the piston 1
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from up position to the down position constituting a third stroke. The third stroke is a power stroke and provides power to run the engine during all six strokes. Both valves 3 and 6, during the power stroke, generally remain closed. During the fourth stroke the piston 1 moves from down position to up position and the out let valve 6 is opened to facilitate discharge of the exhaust gases through the exhaust port (not shown). The outlet valve 6 is opened with the help of a rocker arm 8 and a special shaped cam 9 (see figure 1B). Now the fifth stroke takes place and during this stroke the piston 1 moves from up position to the down position. At the end of the fourth stroke and beginning of the fifth stroke the outlet valve 6 is opened partially to facilitate movement of the piston 1 during fifth stroke. Subsequently, valve 6 is opened fully to discharge exhaust gases through the exhaust port and during the sixth stroke. The piston 1 moves from down position to the up position so as to discharge the residual burnt gases completely from the cylinder 2. Thus the exhaust gases are taken out from the cylinder 2 two time once during the fourth stroke and finally during the last / sixth stroke. This complete discharge of the burnt gases gives more room for the fresh fuel to be admitted during the first stroke and due to absence of the residual gases in the cylinder 2. Also due to the extra revolution of the piston 1 inside the cylinder 2 it provides more time to cool the engine and thus heating of the engine has been reduced and therefore efficiency of the engine has been increased. The life of the engine has thus increased due temperature drop in the cylinder body. In one embodiment and if the six stroke engine of the present
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invention is used to run a vehicle the mileage of the vehicle is increased in the range of 20 to 40 %.
Referring to figures 2A and 2B, special shaped cam are shown. The special shaped cams 5 and 9 are divided into six equal parts so as to provide extended arc 10 and 11 on the outer side of the periphery of the cams 5 and 9, but over a specific part(s), for example, 1, 2 and 3. The extended arc 10 is provided over part 1 of the inlet cam 5 and the extended arc 11 is provided over parts 1, 2 and 3 of the outlet cam 9.
Referring to figures 3 and 4 and according to an option of the present invention the height of the extended arc 10 is in the range of 1.1mm to 2.9mm (please see figure – 3) such that the maximum height is at the center of the part 1 of the inlet cam 5. Similarly, the height of the extended arc 11 is in the range of 1.1mm to 2.9mm (please see figure – 4) such that the maximum height is at the center of the parts 2 and 3 of the inlet cam 9. These, heights of the extended arcs 10 and 11 have been provided over part 1 of the inlet cam 5 and over plurality of parts, for example, parts 1, 2 and 3 of the outlet cam 9 such that to regulate the strokes in order to get the maximum power from the engine and also to provide euro effects to the engine in order to reduce pollution to the environment as the exhaust consisting of carbon mono oxide (Co) stops for some time during 5th stroke and allow to exit during sixth stroke. The special shapes to the inlet cam 5 and outlet cam 9 are provided to operate the opening and closing of the inlet and outlet valves 3 and 6 properly such that to exhaust the burnt gases completely and at the proper time and thus to obtain
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optimum power / efficiency of the engine. The extended arcs / extensions 10 and 11 are provided on the periphery of the cams 5 and 9 to synchronize opening and closing of the fuel inlet and fuel outlet valves 3 and 6 respectively at the proper time in order to provided sufficiently amount of fuel to the engine and exhaust of the burnt gases from the piston – cylinder assembly completely and thus increase efficiency and life of the engine and also to reduce pollution generated by the IC engines.
According to an option of the present invention the special shaped cams 5 and 9 are provided in such a manner that the inlet valve is opened for a longer time such to supply a little more fuel so as to generate more gases after combustion in order to facilitate fifth and sixth strokes to remove the burnt gases from the cylinder completely during the sixth stroke.
The cam 5 is provided to operate inlet valve 3 such that to open the inlet valve 3 to allow fuel intake during first stroke of the engine only by opening the inlet valve 3 and keep it closed during all the subsequent strokes.
The cam 9 is provided to operate outlet valve 6 comprises an extension 11 having a curve on one side such that to open the outlet valve 6 fully during fourth stroke and partially in the beginning of the fifth stroke and fully during sixth stroke and keep it closed during all the other strokes.
Reference in now made to figures 5A and 5B, where in rocker 4 is shown. The rocker 4 comprises two parts. First part 12 is provided between the center of the
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roller 13, adapted to act with the special shaped cam 5 and 9, and center of the pivot 14 on which the rocker 4 is supported and second part 15 is provided between the center of the pivot 14 and the other end 16 of the rocker 4. The ratio of the lengths of the first part 12 and the second part 15 is in the range of 1 : 2 and 1 : 3, respectively. The ratio of the lengths of the parts is provided such that to obtain maximum power during the operation of the engine and minimum unburnt fuel during its operation.
According to an embodiment of the present invention the timing of combustion of the fuel is set in such a manner that the fuel is burnt once in three revolutions of crank shaft.
According to an embodiment of the present invention a plurality of the six stroke engines are arranged in such a manner that sufficient amount of power is generated to complete the task by the engines, for example, heavy vehicles movement.
Certain features of the invention have been described with reference to the example embodiments. However, the description is not intended to be construed in a limiting sense. Various modifications of the example embodiments as well as other embodiments of the invention, which are apparent to the persons skilled in the art to which the invention pertains, are deemed to lie within the spirit and scope of the invention.

I claim;
1. An improved six stroke engine comprising a piston adapted to be disposed in a cylinder such that to be moved up and down upon burning of fuel in the cylinder, inlet and outlet valve opening cams and rocker of a special shapes being provided to operate an inlet valve and an outlet valve such that to provide six strokes in one combustion wherein during fourth stroke outlet vale is opened fully for full time and during fifth stroke the outlet valve remains open partially for some time such that to get back a little amount of exhaust gases and hold it to facilitate fifth stroke and exhaustion of the residual burnt gases completely from the cylinder during sixth stroke keeping outlet valve opened completely during sixth stroke.
2. The improved six stroke engine as claimed in claim 1, wherein special shaped inlet cam is provided with an extension arc of the height in the range of 1.1mm to 2.9mm over a part of the cam such that the inlet valve is opened during inlet stroke for longer time to supply a little more fuel to generated more gases.
3. The improved six stroke engine as claimed in claim 1, wherein the special shaped outlet cam is provided with an extension of the height in the range of 1.1mm to 2.9mm over a plurality of parts of the cam such that outlet valve is opened fully during fourth exhaust stroke, partially in the beginning of the fifth stroke and fully during sixth exhaust stroke.
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4. The improved six stroke engine as claimed in claim 1, wherein the ratio of the length provided between the center of the roller and center of pivot and center of pivot and other end of the rocker is in the range of 1 : 2 to 1 : 3.
5. The improved six stroke engine as claimed in any of the preceding claim for use in a vehicle.
6. The improved six stroke engine substantially as herein described and illustrated in the accompanying drawings.