FIELD OF THE INVENTION

The invention relates to an improved air compressed engine system. In particular this invention relates to an improved air compressed engine system using compressed air or inert gas as fuel to run the automobile.

BACKGROUND OF INVENTION

Automobiles are responsible for a tremendous amount of air pollution and wastage of energy. These problems impact people all over the world, both motorists and non-motorists alike, by affecting their health, their economies, and their communities.

Most of the automobiles pollute by emitting lead from leaded petroleum/ fossil oil. Although the use of lead in petroleum is banned in certain countries like United States, leaded petroleum is still very common in other countries. In fact, of the countries for which data is available, 43% use nothing but leaded petroleum. Many of the rest use at least some leaded petroleum in their energy / fuel mix. This is a definite cause for concern.

The harmful side effects of the fossil fuels in general and automobile pollution in particular, drive the need for a clean and environmentally friendly fuel. This lead to various inventors looking for different fuel sources. Thus the field of alternative fuels was born. The important aim of these alternative fuel technologies is to produce a power source as efficient and powerful as the existing internal combustion (I.C.) engine.

In all these alternative forms of technology, the common process is combustion. This is the primary reason for emission of pollutants. To ensure nearly zero emissions we have to seek for a power generation process without combustion. One of such existing technology is to use of compressed air engine instead of a traditional I.C. engine.

A compressed air engine/air engine, or sometime also referred as pneumatic motor, is a type of motor which does mechanical work by expanding compressed air.

The basic principle of the air engine is derived from the steam engine in which the pressure energy of steam is converted to kinetic energy:

PRESSURE ENERGY -» KINETIC ENERGY

The air engine uses compressed air instead of steam. The compressed air has pressure which on expansion moves the piston (linear motion) which is converted to rotary motion through crank and connecting rod mechanism.

The main problem of this engine is the indirect use of energy. Energy is used to compress air, which in turn provides the energy to run the engine. Any conversion of energy between forms, results in loss.

Also due to the conversion of pressure energy to the kinetic energy, the piston is subjected to various forces which make the engine to vibrate heavily when compared to the normal IC engine.

Further, according to Charle's law, when air expands in the engine it cools dramatically which makes the engine less efficient during cold climates. Conversely, when air is compressed to fill the tank it heats up. If the stored air is not cooled as the tank is filled, then when the air cools off later, its pressure decreases and available energy decreases.

Further, refueling of the existing compressed air tank using a home or conventional air compressor may take as long as 4 hours. Also in case of any unfortunate accidents/ crashes, there is a high probability that the air tank filled with compressed air may burst out with high intensity unless taken necessary measures. Further, the automobile running with the existing air compressed engine cannot carry heavy loads.

SUMMARY OF INVENTION

Accordingly the present invention provides an improved air compressed engine system using compressed air as fuel to run an automobile.

The present invention provides a simple, cost effective, environment friendly air compressed engine system using compressed air or pure inert easily available gas such as nitrogen gas as fuel to run an automobile, comprising of the engine, the de-humidifying filter and the air pre-heater mechanism before the inlet opening, connected with the Compressed Air Tank (Fig 5), wherein the engine is characterized by the cam shaft and timing gear are in such a way so that the inlet valve for compressed air opens at around 10 to 20 degrees angle, preferably 15 degrees angle, after Top Dead Centre (TDC) and closes 25 degrees angle just before Bottom dead centre (BDC) to cut off the air supply to the engine. In another embodiment of the invention, the idle gear is used in the cam shaft rod of the invention has equal teeth of that of the gear connected to the crank shaft, so as the number of rotations of crank shaft and cam shaft becomes equal.

Further, the present invention provides a suitable air pre-heater mechanism to heat the compressed Air just before it enters into the Inlet valve. The pre-heater mechanism comprises of at least one Compressed Air Tank, is made up of a composite material made up of carbon-Fiber and thermo-setting plastic or such other durable light material or steel, a suitable on-board compressor running on DC current to provide continues supply of compressed air to the compressed tank of the automobile, at least one suitable de-humidifying filter attached before the inlet valve of the engine to prevent entering of the moisture into the cylinder /tank, and using of any easily available inert gas such as nitrogen or normal atmospheric air as the compressed gas as a fuel to run the automobile.

DESCRIPTION OF ACCOMPANYING DRAWINGS

The invention can be better understood with reference to the following figures. The components within the figures are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the invention. Moreover, in the figures, like reference numerals designate corresponding parts throughout the different views. It will also be understood that certain components and details may not appear in the figures to assist in more clearly describing the invention.

Fig. 1 is the valve timing diagram of the invention

Fig. 2 is a schematic diagram of the power stroke showing the mechanism of opening of inlet valve and the incoming of the compressed air inside the cylinder and moving of the piston downwards toward the Bottom dead centre (BDC)

Fig. 3 is a schematic diagram of exhaust stroke through vent showing upon the piston reach the BDC, the exhaust vent is opened to let the compressed air inside the cylinder move out of the cylinder.

Fig. 4 is a schematic diagram of exhaust stroke showing the left air inside the cylinder is let out through the exhaust vent before the piston reaches the Top dead centre (TDC).

Fig. 5 is a schematic diagram of the invention with air tank.

In the description below, the full description of the used technical terms/abbreviation are as follows:

1. TDC- Top dead centre

2. BDC-Bottom dead centre

3. ICE - Internal combustion engine

4. IVO-Inlet valve open

5. IVC- Inlet valve close

6. EVeO-Exhaust vent open

7. EVeC-Exhaust vent close

8. EVO- Exhaust valve open

9. EVC- Exhaust valve close

DETAILED DESCRIPTION OF INVENTION

The present invention is capable of multiple embodiments and if required depending be used in multiple numbers simultaneously and not in any way restricted in scope and ambit by the within contained description and drawings.

The following embodiments will illustrate certain aspects of the invention. It should be understood however that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. The following description is not to be construed as limiting the invention. Many modifications and other embodiments of the inventions set forth herein will come to mind to one skilled in the art to which these inventions pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the inventions are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

In an embodiment the invention provides a simple, cost effective, environment friendly air compressed engine system using compressed air or pure inert easily available gas such as nitrogen gas as fuel to run an automobile, comprising of the engine, the de-humidifying filter and the air pre-heater mechanism before the inlet opening, connected with the Compressed Air Tank (Fig 5), wherein the engine is characterized by the cam shaft and timing gear are in such a way so that the inlet valve for compressed air opens at around 10 to 20 degrees angle, preferably 15 degrees angle after Top Dead Centre (TDC) and closes at 25 degrees angle just before Bottom dead centre (BDC) to cut off the air supply to the engine.

In an embodiment of the invention the existing 4S (Four Stroke) petrol engine is designed to operate on the compressed air. In this embodiment 100 CC 4S (4 Stroke) Engine was taken and converted into a 2S (Two Stroke) engine by modifying the cam shaft and timing gear on the cam shaft in order to have a power stroke for every cycle; otherwise air pressure may not be sufficient to overcome the back pressure in the dead cycle.

In another embodiment of the invention, 4S (4 Stroke) Engine is converted into a 2S (Two Stroke) engine and by using the idle gear in cam shaft rod which has equal teeth of that of the gear connected to the crank shaft, so that it becomes a 2 stroke as the number of rotations of crank shaft and cam shaft becomes equal.

Further, in the invention the timing chain has been reduced to minimize the slag, the spark plug from the ICE is removed since there will not be any requirement for any form of combustion. The exhaust vent of appropriate diameter preferably of 5 mm is drilled on the surface of cylinder as per the timing diagram. The timing is controlled exactly as per required by means of the timing gear and chain.

In yet another embodiment of the invention the opening and closing of the valves and the exhaust vent of the existing 4S or 2S engines are so adjusted that air engine produces power to drive the vehicle. The cam shaft and timing gear are so designed that the inlet valve for compressed air opens at around 10 to 20 degrees angle, preferably 15 degrees angle after Top Dead Centre (TDC). Normally in case of any IC engine combustion starts before TDC to minimize the timing losses. But in the present invention inlet valve cannot be opened before TDC otherwise the piston will go back towards BDC. This inlet valve closes at 25 degrees angle just before BDC to cut off the air supply to the engine.

In yet another embodiment of the invention, instead of letting the normal compressed Air into the Inlet valve of the engine, the invention provides for a suitable air pre-heater mechanism to heat the compressed Air just before it enters into the Inlet valve. Since the density of the hot air is less compared to the normal/cold air, the hot air tends to expand quicker than the normal/cold air. This makes sure that the engine can be operated for a longer time with the same quantity of air and increase its range to a lager extent.

In yet another embodiment of the invention, the Compressed Air Tank, is made up of either steel or preferably of a composite material made up of carbon-Fiber and thermo-setting plastic. The main advantages using the tank made up of carbon-Fiber and thermo-setting plastic are as follows:

• It reduces the weight of the tank by 65 percent when compared to the usual steel tank.

• The maximum pressure that can be stored can be increased to 300 Bar where as the maximum pressure that is stored in the usual steel tank is just 15 Bar.

• The tank made from the Carbon-fiber and Thermo-setting plastics will not burst/explode in an event of any collision; instead it will just crack and let the air out without causing any hazards to the driver/passenger.

• And since the space occupied by this tank can be reduced drastically and more number of such Compressed Air can be fitted in an automobile, which not only will also increase its capacity to take more load but also its efficiency to take the same to the much longer distance.

In yet another embodiment of the invention, a suitable on-board compressor running on DC current is suitably mounted on an automobile to ensure that the on-board compressor to provide continues supply of compressed air to the compressed tank to ensure that the automobile does not have to stop to keep refilling the tank. This substantially increases the automobile range to a large extent.

In yet another embodiment of the invention, a suitable de-humidifying filter is attached before the inlet valve of the engine in order to ensure that the moisture doesn't enter into the engine and in order to prevent any chances of accumulation of water inside the cylinder/tank.

In yet another embodiment of the invention, only the pure inert easily available gas such as preferably nitrogen gas is used in order to improve the efficiency of the engine. Further using of nitrogen as the compressed gas has its own advantages since the molecular weight of Nitrogen is less than the molecular weight of the Natural Air and the compression ratio of Nitrogen can be increased. Further, it is most abundantly available inert gas in our environment.

In the invention, the cycle of operation gets completed with two strokes of the piston or one revolution of the crank. These two strokes are,

a. Expansion or Power stroke.

b. Exhaust stroke.

a. Expansion or Power stroke

During this stroke the piston moves from the TDC to BDC. At the beginning of this stroke the inlet valve is opened and allows the compressed air stored in the tank to expand inside the cylinder. This moves the piston down as pressure energy of air gets converted into kinetic energy thus producing a power stroke.

Just before reaching BDC the cam mechanism closes the inlet valve and the piston uncovers an exhaust vent through which the expanded gas escapes to the atmosphere. This reduces the load on the piston by reducing the amount of air present inside the cylinder during return stroke.

b. Exhaust stroke

During this stroke piston moves from BDC to TDC. Initially the piston covers the exhaust vent and the cam mechanism opens the exhaust valve. Most of the air is expelled to the atmosphere through this exhaust vent.

Usually in case of any IC engine combustion starts before TDC to minimize the timing losses. But in case of the Compressed Air Engine inlet valve cannot be opened before TDC otherwise the piston will go back towards Bottom dead centre (BDC). This inlet valve closes 25 degrees just before BDC to cut off the air supply to the engine.

During its upward journey of the piston towards TDC, pressure develops further due to the air left in the cylinder after the piston shuts off the exhaust vent. To overcome this pressure power will be consumed from the output shaft. Since there is no scavenging or any other type of fuel loses in compressed air engine, a 3 to 7 mm (preferably 5 mm) diameter exhaust vent is provided 15 to 20 degrees (preferably degrees) before BDC. This crank angle and diameter was selected by repeated trials. So when the piston passes through the vent, pressure inside the cylinder will become atmospheric; 18 degrees after BDC, when the vent closes, since already there is some momentum in the piston it will tend to move up to 35 degrees after BDC. At that point of time exhaust valve opens in order to maintain the pressure inside the engine at atmospheric level. Exhaust valve also cannot be opened for longer period of time otherwise towards BDC piston will have a pulsating behavior. Due to the improved design of the cam shaft and timing gear of the present invention, exhaust valve closes 45 degree before TDC. Next 60 degrees of crank rotation piston will rotate purely due to inertia. This sequence of events of the valve timing diagram is as shown in Figure 1. From figures 2-4 shows the movement of air with respect to the piston position.

Advantages:

• Compressed air engines of the present invention reduce the cost of vehicle production, because there is no need to build a cooling system, spark plugs, starter motor, or mufflers

• The rate of self-discharge is very low opposed to batteries that deplete their charge slowly over time. Therefore, the vehicle may be left unused for longer periods of time

• Expansion of the compressed air lowers its temperature; this is exploited for use as air conditioning.

• Reduction or elimination of hazardous chemicals such as flammable petroleum fuel or battery acids/metals

• The improvised mechanical configurations of the present invention allow energy recovery during braking by compressing and storing air.

• There is no huge sound or vibration, attributable to detonations in the engine, in the present invention, resulting inter-alia longer life to the engine.

• There is no need to have a cooling system since there is no combustion required, this inter-alia helps in reducing the weight of the automobile and makes it more efficient to run the longer distance.

• No harmful pollutants are released into the atmosphere due to combustion as the fuel used in the present invention is the air, helping the automobile with the present invention substantially reducing its carbon footprint.

The invention is capable of multiple embodiments and if required depending upon the requirement be used in multiple numbers simultaneously by the person skilled in the art and not in any way restricted in scope and ambit by the within contained description and drawings.

This application proposes a invention to provide a novel portable, cost effective , environmental friendly, easy to use and maintain, air compressed engine to run an automobile and capable to use take relatively larger loads to longer distances.

I claim:

1. An improved air compressed engine system comprising of:
an engine, a de-humidifying filter and air pre-heater mechanism before the inlet opening, a Compressed Air Tank with air compressor connected with power source, wherein the inlet valve opening of the engine is at around 10 to 20 degrees angle, preferably 15 degrees angle after Top Dead Centre (TDC) and closes at 25 degrees angle just before Bottom dead centre (BDC) to cut off the air supply to the engine.

2. The improved air compressed engine system as claimed in claim 1, wherein the said engine can either be a modified 4S engine or a modified 2S engine.

3. The improved air compressed engine system as claimed in claim 1, wherein the 4S engine modified to the 2S engine either by adjusting the cam shaft and timing gear for having the power stroke for every cycle or providing the idle gear in cam shaft rod with equal teeth of that of the gear connected to the crank shaft for having the equal number of rotations.

4. The improved air compressed engine system as claimed in claim 1, wherein the timing chain has been reduced to minimize the slag.

5. The improved air compressed engine system as claimed in claim 1, wherein the air pre-heater mechanism is provided to heat the compressed Air just before it enters into the inlet valve of the engine.

6. The improved air compressed engine system as claimed in claim 1, wherein the Compressed Air Tank is preferably made up of the composite material comprising of carbon-Fiber and thermo-setting plastic.

7. The improved air compressed engine system as claimed in claim 1, wherein the power resource for running the air compressor is DC current.

8. The improved air compressed engine system as claimed in claim 1, wherein the pure inert easily available gas such as nitrogen is used as a fuel.