WO2016024175A1

WO2016024175A1 - Gas pressure regulator for two wheeler

Info

Publication number: WO2016024175A1
Application number: PCT/IB2015/054682
Authority: WO
Inventors: Michael ANGADJI
Original assignee: Angadji Michael
Priority date: 2014-08-12
Filing date: 2015-06-23
Publication date: 2016-02-18

Abstract

The present disclosure relates to a cost effective and easy to install pressure regulator for two wheeler that reduces CNG pressure from its storage pressure of about 200 bar to less than 1 bar in two stages without any adverse effect of cooling of gas due to expansion and heating of cooled gases. The second stage pressure regulator also incorporate flow control valve and means to adjust idling speed and performance of engine thereby reducing number of assemblies, pipes and hardware making it cost effective for two wheeler application.

Description

GAS PRESSURE REGULATOR FOR TWO WHEELER

TECHNICAL FIELD

[1] The present disclosure generally relates to the field of transport vehicles. More specifically, it pertains to two wheeler configured to run on gaseous fuel such as CNG. In particular, it pertains to gas pressure reducer and regulator for two wheelers.

BACKGROUND

[2] Background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.

[3] A large number of people especially in places where public transport is not well developed are dependent on personal vehicles for their transportation needs. Almost all these vehicles use internal combustion engines(IC engines) as prime mover and fossil fuels like petrol and diesel to run them. These prime movers using petrol or diesel cause pollution both at local level by emitting harmful gases such as nitrogenous oxides particulates and also at global level by adding to greenhouse gases. However, efforts to develop alternatives such as electrically driven personal transport depending on renewable sources of energy for driving personal transport have so far failed to cross bar of commercial viability.

[4] Till such time newer technologies bring about radical change in the way transport vehicles are fuelled, environmental challenges are being met by laying down pollution control requirements for fossil fuel driven vehicles which require these vehicles to restrict their emissions within the prescribed limits. Engine/vehicle designers and manufacturers are continuously improving the engine designs and exhaust systems to reduce emission levels and meet the statutory requirements.

[5] One area which can have considerable effect on pollution from internal combustion engines is choice of fossil fuel. It is known that natural gas(in compressed state to reduce space it would otherwise occupy and therefore Compressed Natural Gas(CNG)) whose main constituent is methane, and Liquefied Petroleum Gas (LPG) produce significantly fewer pollutants such as carbon dioxide, unburned hydrocarbons, carbon monoxide, nitrogen oxides, sulphur oxides and particulate matter than petrol or diesel. Besides being less polluting, they also have other advantages such as increased life of lubricating oils, no fouling of spark plugs(in case of spark ignition engines), lower maintenance costs etc. CNG specifically is also safer than other fuels in the event of a spill because natural gas is lighter than air and disperses quickly when released. For aforementioned reasons natural gas in particular is now being extensively used on public transport vehicles in many cities.

[6] In view of lower cost of CNG and overall economy in operation, it is turning out to be quite popular among individuals for personal transport vehicles also. For this reason, many car manufactures are manufacturing models that incorporate CNG as an optional fuel. However, requirement of those in lower income segment in developing countries and operating cheaper mode of personal transport such as two wheelers remains unmet. The segment requires low cost solution suitable for fitment on two wheelers both as OE and conversion kit to meet requirement of new as well as already operational two wheelers.

[7] CNG on account of being in gaseous state at room temperature has low density and therefore has to be typically stored at high pressures to reduce occupied space. For consumption its stored pressure has to be reduced to working pressure at the same time ensuring required flow rate and pressure as consumption of gas takes place. Pressure reducer and regulator (also known in art as pressure regulator or pressure reducer and terms used interchangeably hereinafter) are typically used to meet this requirement.

[8] One problem that is encountered in this respect is adiabatic cooling of gas as its pressure is reduced rapidly. The phenomenon causes freezing of regulator body and its diaphragm. This results in dramatically decreased gas flow from regulator and regulator performance fails. Low temperature of gas can create other hurdles also in operation such as condensation of water vapours present in gas that in extreme case may freeze and block gas flow; low temperature may affect combustion in engine affecting efficiency etc.

[9] In vehicles having water cooled engines, problem is solved by routing the gas pipe through a heater that circulates engine coolant to heat the gas and counter the effect of cooling. However in two wheelers that generally have air cooled engines no such option exists. Problem is generally solved by splitting the pressure reduction in two stages that are placed apart connected by pipe thereby slowing down the pressure reduction and allowing in between heating of cooled gas in natural manner. The solution however increases the number of assemblies with added increase in piping, mountings and hardware. Considering space constrains and cost sensitive nature of two wheeler segment it may not be an optimum solution to solve the stated problem in respect of installation of CNG kit on a two wheeler.

[10] There is therefore a need for providing efficient, low cost, and easy to install system for pressure reduction and regulation of CNG gas for enabling two wheeled personal transport vehicles to run on CNG fuel.

OBJECTS OF THE INVENTION

[11] An object of present disclosure is to provide an efficient and cost effective pressure regulator for CNG for two wheelers.

[12] An object of present disclosure is to provide a pressure regulator for CNG for two wheelers that does not require heating of gas to offset cooling effect of its expansion.

[13] Another object of present disclosure is to provide pressure regulator for CNG for two wheelers that reduces number of assemblies, pipes and hardware in CNG installation kit.

[14] An object of present disclosure is to provide a pressure regulator for CNG for two wheelers that is not affected by cooling of gas due to pressure reduction/expansion.

[15] An object of present disclosure is to provide a pressure regulator for CNG that incorporates safety valve to protect from over pressure after reducing element.

[16] An object of present disclosure is to provide a pressure regulator for CNG that incorporates a filter at inlet port to prevent contaminants present in gas from enteringarea housing functioning parts and having narrow passages.

[17] An object of present disclosure is to provide a pressure regulator for CNG that incorporates a flow control valve which controls flow of gas in relation to suction vacuum.

[18] An object of present disclosure is to provide a pressure regulator for CNG that incorporates means to adjust engine idling speed and engine performance. SUMMARY

[19] Aspects of present disclosure relate to a cost effective pressure regulator for gaseous fuel for two wheeler vehicles that reduces pressure of stored CNG gas to working pressure required for mixing with air before feeding to engine and also regulates final gas pressure to predefined values to maintain optimum condition for efficient running of engine.

[20] In an aspect the present disclosure, the regulator does not require heating of gas to counter cooling effect of expansion/pressure reduction of gas and thus is suitable for application on vehicles such as two wheelers that typically have air cooled engines that do not provide any scope of using engine coolant to heat the cooled gas.

[21] In another aspect of the present disclosure, the pressure reduction can be achieved in two stages, with the first stage reducing the pressure to an intermediate pressure and the second stage further reducing it to working pressure suitable for mixing with air before intake by engine. Further the two stages can be housed in two separate assemblies.

[22] In yet another aspect of the present disclosure, pressure regulator assembly housing the second stage can also incorporate means for adjusting engine performance and idling speed of engine that otherwise would be housed in a separate assembly, thereby reducing number of assemblies, pipes and hardware required for installation. Pressure regulator of present disclosure therefore results in overall economy and ease of assembly of CNG kit.

[23] In yet another aspect of the present disclosure, first stage pressure regulator is configured such that it is not affected by cooling of gas due to pressure reduction/expansion. It has Piston type reducing element with its two ends having different area and reduces pressure in accordance with area ratio of the two ends. It also maintains output pressure within the requisite range under condition of varying input pressure delivered by CNG tank from full condition to near empty condition.

[24] In yet another aspect of the present disclosure, first stage pressure regulator incorporates features such as safety valve after reducing element for protection from over pressure and a filter at inlet port to prevent contaminants present in gas from entering area housing functioning parts and having narrow passages. Further first stage regulator is small in size and can fit in any small space making it suitable for two wheeler application. [25] In yet another aspect of the present disclosure, second stage pressure regulator can incorporate a diaphragm and lever mechanism to reduce pressure from intermediate stage to a working pressure. It can further incorporate an additional third regulator stage by way of a normally close diaphragm valve that opens by vacuum action of the engine and thus functions as flow control valve. The flow control valve controls flow of gas in relation to the amount of vacuum behind its diaphragm. Further, second stage of the pressure regulator can incorporate means to adjust engine idling speed, and third stage of the pressure regulator incorporates means to adjust engine performance by way of two adjustment screws positioned suitably for ease of adjustment by operator/service man.

[26] In yet another aspect of the present disclosure, second stage pressure regulator can incorporate a safety valve configured to protect downstream from over pressure and a solenoid valve that can be configured to control passage of gas into third stage in accordance with fuel selection by user i. e. allow gas to flow to third stage when the fuel selection switch is on CNG mode and block flow in other position.

BRIEF DESCRIPTION OF THE DRAWINGS

[27] The accompanying drawings are included to provide a further understanding of the present disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[28] FIG. 1 illustrates an exemplary sectional view of first stage regulator in accordance with embodiments of present disclosure.

[29] FIG. 2 illustrates an exemplary exploded view of parts of first stage regulator in accordance with embodiments of present disclosure.

[30] FIG. 3 illustrates an exemplary exploded view of parts of second and third stage regulator in accordance with embodiments of present disclosure.

DETAILED DESCRIPTION

[31] Unless the context requires otherwise, throughout the specification and claims which follow, the word "comprise" and variations thereof, such as, "comprises" and "comprising" are to be construed in an open, inclusive sense that is as "including, but not limited to."

[32] Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[33] As used in this specification and the appended claims, the singular forms "a,"

"an," and "the" include plural referents unless the content clearly dictates otherwise. It should also be noted that the term "or" is generally employed in its sense including "and/or" unless the content clearly dictates otherwise.

[34] The headings and abstract of the disclosure provided herein are for convenience only and do not interpret the scope or meaning of the embodiments.

[35] Reference will now be made in detail to the exemplary embodiments of the present disclosure, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts.

[36] The following discussion provides many example embodiments of the inventive subject matter. Although each embodiment represents a single combination of inventive elements, the inventive subject matter is considered to include all possible combinations of the disclosed elements. Thus if one embodiment comprises elements A, B, and C, and a second embodiment comprises elements B and D, then the inventive subject matter is also considered to include other remaining combinations of A, B, C, or D, even if not explicitly disclosed.

[37] Embodiments of present disclosure describe a cost effective gas pressure regulator for two wheelers that reduces pressure of stored CNG gas from about 200 bar to less than 1 bar that can be the working pressure for mixing with air before feeding to engine. The regulator of the present disclosure in addition regulates final gas flow to engine in accordance with requirement to maintain optimum condition for efficient running of engine. It should be appreciated that various embodiments of the present disclosure have been explained with reference to CNG as gaseous fuel, however, these after suitable alterations/modifications that shall be apparent to a person skilled in art can be equally applied to other gaseous fuels such as LPG and all such applications are well within the scope of present disclosure.

[38] In an embodiment of the present disclosure, pressure reduction from storage pressure of about 200 bar to working pressure of less than 1 bar can be carried out in two stages, firstly from high storage pressure to an intermediate pressure of say 8-12 bar and thereafter in second stage from intermediate pressure to working pressure of less than 1 bar. In an aspect, the two stages of pressure reduction can be housed in two different assemblies and the regulator does not require heating of gas to counter cooling effect of expansion/pressure reduction of gas, and thus is suitable for application on vehicles such as two wheelers that typically have air cooled engines thus not providing any scope of using engine coolant to heat the cooled gas.

[39] In an aspect reduction of gas pressure in two stages, two stages work on different concepts wherein first stage of pressure reduction is based on piston type mechanism and second stage a diaphragm type reduction mechanism. First stage that does major part of pressure reduction from 200 bar to 8 - 12 bar experiences most of the cooling effect due to expansion of gas and is therefore configured with a piston type of reducing element does not get affected by cooling of gas due to pressure reduction/expansion.

[40] In another aspect, piston type reducing element as is known in the art, on account of sluggish action due to frictional force on sealing elements in moving parts such as Ό' rings on piston, tend to have variation in output pressure. To overcome this deficiency a diaphragm type mechanism that inherently have quick response and therefore regulate pressure more precisely has been used in second stage of regulator. Thus the two stage regulator of the present disclosure incorporates features and parameters that allow pressure reduction from high storage pressure of about 200 bars to low working pressure of less than 1 bar without adverse effects of cooling of gas on account of expansion/pressure reduction at the same time ensuring a stable output pressure.

[41] In another embodiment, piston type of reducing element of first stage pressure regulator is configured with its two ends having different area that produce pressure ratio in accordance with area ratio of the two ends. It also maintains output pressure within the requisite range of 8 to 12 bar even as input pressure delivered by CNG tank varies from 200 bar to 20 bar from its full condition to near empty condition.

[42] In another embodiment, piston type of reducing element of first stage pressure regulator that reduces pressure in accordance with area ratio of the two ends does not need any adjustments for pressure setting that are otherwise essentially required on regulators that regulate pressure in relation to atmospheric pressure. Therefore this feature makes the regulator easy to manufacture, maintain and service. In an aspect, variation of pressure as input pressure delivered by CNG tank varies from its full condition to near empty condition is taken care of in second stage regulator that is configured to regulate pressure in relation to atmospheric pressure.

[43] In an embodiment input and output ports of first stage pressure regulator are configured along centreline of its body/housing which enables its assembly on vehicle in line with pipe route without any bending of pipe merely to accommodate the regulator thus making its installation easy and cost effective. Further first stage regulator is light weight and small in size/diameter and can fit in any small space making it suitable for two wheeler application.

[44] In yet another embodiment first stage pressure regulator incorporates features such as safety valve after reducing element for protection from over pressure and a filter at inlet port to avoid contamination of the gas to prevent contaminants present in gas from entering area housing functioning parts and having narrow passages.

[45] In an embodiment assembly housing the second stage pressure regulator also incorporates flow control valve, means for adjusting engine performance and idling speed of engine that otherwise would be housed in a separate assembly thereby reducing number of assemblies, pipes and hardware required for installation. Pressure regulator of present disclosure therefore results in overall economy and ease of assembly of CNG kit. Flow control valve also called as third stage pressure regulator (the two terms used interchangeably herein after) is housed in a separate chamber in second stage pressure regulator and it is a normally close diaphragm valve that opens by vacuum action of the engine and functions as flow control valve. The flow control valve controls flow of gas in relation to the amount of vacuum behind its diaphragm. The second stage also incorporates means to adjust engine idling speed, and third stage of pressure regulator includes means to adjust engine performance by way of two adjustment screws positioned suitably for ease of adjustment by operator/service man.

[46] In yet another aspect second stage pressure regulator incorporates a safety valve configured to protect downstream from over pressure and a solenoid valve that can be configured to control passage of gas into third stage in accordance with fuel selection by user i. e. allow gas to flow to third stage when the fuel selection switch is on CNG mode and block flow in other position.

[47] FIG. 1 illustrates an exemplary sectional view of the first stage pressure regulatorlOO in accordance with embodiments of the present disclosure. The first stage pressure regulator 100 can include housing lower 102 and housing upper 104 configured to house pressure reducing and controlling elements and can be assembled through pair of internal and external threads configured on the two respectively. The two housings 102 and 104 can also incorporate outlet port 108 and inlet port 106 respectively for passage of gas through the first stage pressure regulator 100. Housing lower 102 and housing upper 104 after assembly can define an internal cylindrical space to accommodate pressure reducing and regulating elements and other associated parts of the first stage pressure regulator 100. In an embodiment housing lower 102 and housing upper 104 can be made of material such as but not limited to brass that can withstand high working pressure of say 250 bar.

[48] In an embodiment first stage pressure reduction is carried out by means of a piston 110 that is cylindrical in shape and with its two ends having different diameters. Larger end of the piston 110 can be configured within lower hosing 102 that carries output port of the first stage pressure regulator 100 and smaller end of the piston can be configured within a cylindrical cavity of spring seat 112. Spring seat 112 can be fixed to housing upper 104 by means of threads and its cylindrical cavity that houses smaller end of the pistonl lO can be in fluidic communication with inlet port 106 through a hole 120 to allow high pressure gas to enter space behind small end of the piston 110.

[49] In an embodiment gas passage from inlet port 106 to hole 120 can be configured with a filter 118 to prevent contaminants present in gas from entering area housing functioning parts and having narrow passages. The filter 118 can be made of material such as but not limited to sintered material that permits gas to pass but traps contaminants. Such filter 118 made of sintered material can be cleaned by suitable solvent and reused at the time of servicing without need of a replacement thus bringing overall economy. Likewise housing lower 102 can incorporate means to house an overpressure safety valve 122 that can detect gas pressure on output side and release gas in the event of output pressure exceeding a predefined limit. The safety valve 122 can protect down line components from damage on account of overpressure.

[50] Piston 110 and spring seat 112 can have a spring 114 configured between them such that it pushes piston 110 towards bottom of cylindrical cavity of housing lower 102 in which piston 110 is configured. Cylindrical cavity of housing lower 102 can be in fluidic communication with outlet port 108. Piston 112 can have a hole running from small end to bigger end allowing gas to flow from small end to bigger end.

[51] In an embodiment of application bigger end of pistonl lO shall, under force of spring, be resting against the bottom face of cylindrical cavity of housing lower 102. Adequate outlet side pressure of gas acting on bigger end of piston 110 can make it move up against combined force of spring 114 and input side gas pressure acting on smaller end of the piston 110. As the piston 110 moves up, smaller end of piston 110 can block gas passage at hole 120 by means of disc 116 configured at small end of the piston. In application when inlet port 106 receives high pressure gas from storage means, gas can travel through different passages to reach outlet port 108. As flow of high pressure gas continues, pressure on outlet side can start building up and act on bigger end of the piston 110 to reach a level that is enough to overcome combined effect of spring force and force of high gas pressure acting on smaller end; in which case piston 110 can start moving up and finally disc 116 can block hole 120 stopping flow of high pressure gas. As flow of gas stops, consumption of gas at outlet end can reduce its pressure making pistonl lO to move down opening the gas passage through hole 120. In practice piston 110 can continuously move up and down to allow or block the gas flow so as to maintain pressure at output port 108.

[52] As would be apparent to those skilled in art, in piston type of reducing element with its two ends having different area, relationship between input pressure and output pressure shall be controlled by area ratio of small end and bigger end of piston 110. Therefore, as input pressure delivered by CNG tank varies from full condition to near empty condition, output pressure shall also vary from a higher to lower value. In an embodiment of the present disclosure, a proper choice of area ratio and spring force ensures that output pressure remains within a range of 8 bar to 12 bar despite variation in pressure delivered by CNG tank that typically varies from 200 bar to 20 bar from full condition to near empty condition.

[53] In an aspect, piston type of reducing element does not get affected by cooling of gas due to adiabatic expansion as its pressure drops from about 200 bar to about 10 bar as would be the case with diaphragm type reducer/regulator where freezing of the regulator body and its diaphragm results in dramatic decrease in gas flow from regulator and failure of regulator performance. Piston 110 and other regulator components are made of materials that remain unaffected by low temperature. Also, low temperature does not affect free movement of piston 110 which is crucial for pressure regulation. Various sealing parts such as disc 116 are also made of materials that remain free from adverse effects that may affect proper functioning of regulator 100.

[54] In an aspect, first stage regulator 100 of the present disclosure that employs piston type reducing element does not have any adjusting element to adjust the output pressure. The output pressure is inherently controlled by design configuration and thus is simple to manufacture, maintain and service. Also it is small in size such that it can be fitted in small space. These features make the first stage regulator 100 ideal for cost conscious and space constrained transport segment such as two wheelers.

[55] FIG. 2 illustrates an exemplary exploded view 200 of components of first stage regulator 100 in accordance with embodiments of the present disclosure. Depicted therein are housing lower 102, housing upper 104, input port 106,output port 108, Piston 110, spring seat 112, spring 114, seat disc 116, filter 118 and hole 120. Also depicted is overpressure safety valve 122.

[56] FIG. 3 illustrates an exemplary exploded view of second stage regulator 300in accordance with embodiments of the present disclosure. In an embodiment assembly housing the second stage of pressure reduction also houses flow regulator and idle speed adjustments thereby reducing number of assemblies, connecting pipes and mounting hardware making the pressure regulator of the present disclosure cost effective and suitable for application in two wheelers. Depicted in FIG. 3 is body 302 of the second stage regulator 300 that is configured with a partition dividing it into two chambers, each housing a different stage of pressure reduction and/or regulation. In the exemplary configuration left side chamber 304 houses second stage of pressure reduction and right side 306 houses normally closed valve and flow control adjustment. Idle speed control and solenoid valve are configured between second and third stage in the main body of the regulator 302.

[57] Exemplary body 302 can be configured with an inlet port 310 which can be in fluidic continuity with left side chamber 304 of body 302 housing second stage pressure regulator. Inlet port 310 can be configured with an adopter 312 to facilitate fixing of pipe carrying gas from first stage pressure regulator. Body 302 can additionally have a mounting pad 308 configured with holes to facilitate mounting with help of a suitable bracket (not shown).

[58] Left side chamber 304 of body 302 can be closed by a cover 314 and house within the chamber first diaphragm 316, spring 318 and first balance lever 320 that can be three elements of second stage pressure reducer and regulator. Diaphragm 316 under pressure of spring 318 can move back and forth as gas pressure in chamber changes. First balance lever 320 can be pivotally fixed in body 302 with its one end suitably connected to first diaphragm 316 such that when first diaphragm 316 moves back and forth under influence of change in gas pressure, first balance lever 320 moves about its pivot. Other end of the first balance lever 320 can be configured to control gas passage that connects inlet port 310 to left chamber 304 such that it allows gas to enter the left chamber 304 when pressure in the left chamber 304 is below a predefined value and blocks the passage when gas pressure in left chamber 304 goes above the predefined limit. Thus the second stage pressure regulator reduces and regulates the gas pressure to final working pressure of say less than 1 bar.

[59] A safety device 332 can be configured after stage two and before stage 3, housed in the main body of 302 that control the output pressure of stage 2 to be within predefined limit of working pressure. It discharges the extra gas in event of excessive pressure to stop gas flow with over pressure to the third stage and prevent damage.

[60] Cover 324 of right chamber 306 can be configured with an adjusting device 338 as means to adjust amount of gas flowing to gas mixer at certain amount of throttling and vaccum to optimize engine performance.

[61] Right side chamber 306 of the body 302 can be configured with flow control means. Flow control valve can work as a normally close diaphragm valve that can open by vacuum action of the engine and function as flow control valve. Thus flow control valve controls flow of gas in relation to the amount of vacuum behind its diaphragm as a result of throttling action of two wheel driver, and can additionally incorporate means to adjust performance of engine.

[62] Right side chamber 306 can be configured with an output port 336 that can supply gas from second stage regulator 300 to air gas mixer of engine through pipe connected to output port 336. As flow control valve works as a normally closed valve, no gas can be fed to engine through output port 336 until throttling action by the driver and consequently adequate vacuum is created to open flow control valve to allow gas to flow. Requirement of gas for idle running of engine can be met by tapping gas from left side chamber 304 and supplying it directly to output port 336 by means such as a tube 332 bypassing right side chamber 306.An idle speed adjusting valve 330 can be configured in this passage to control/adjust amount of gas that can move to output port 336 and thus control idle running speed of engine. In practice idle speed adjusting valve 330 can tap gas from left side chamber 304 at its input side and one end of tube 332 can be connected to its output side. Idle speed adjusting valve 330 can be a needle type valve that can reduce or increase amount of gas passing through it depending on its position that can be changed by adjusting means such as an adjusting screw. Thus idle speed of engine can be varied/adjusted by means of adjusting screw configured on the idle speed adjusting valve 330.

[63] Right side chamber 306 of body 302 can be closed by a cover 324 and house within the chamber second diaphragm 326 and second balance lever 328 that can be the elements of flow control valve. The two can function in same way as first diaphragm 316, and first balance lever 320 of left side chamber 304 to control flow of gas from left side chamber 304 to right side chamber 306. Movement of second diaphragm 326 can be under influence of vacuum in right side chamber 306 that is in communication with air gas mixer of engine through outlet port 336. Thus when engine throttle is pulled a higher vacuum can be created in gas mixer that can be felt on left side of second diaphragm 326 moving it to allow more gas to flow from left chamber 304 to right chamber 306 which can flow to gas mixer through output port 336 thereby providing richer air fuel mixer for engine to develop higher power in response to pulling of throttle. On the other hand as throttle is released lower vacuum can make second diaphragm 326 to move back reducing the gas flow from left chamber 304 to right chamber 306 thereby providing leaner air fuel mixer for engine to develop lower power in response to release of throttle. [64] There can also be a solenoid device (not shown) configured on the body 302 that can electrically control (block or open)passage of gas from the right side of 302 to left side 304 that can help user to switch to gaseous or other fuel on need basis.

[65] Thus the present disclosure provides a pressure regulator that enables reduction of gas pressure from storage pressure of about 200 bar to a working pressure of less than 1 bar in two stages without need of heating the gas to counter cooling effect of adiabatic expansion of gas or without any adverse effect of such cooling on functioning of pressure regulator. It further reduces number of assemblies, pipes and hardware to make it cost effective and easy to install in space constrained and cost sensitive transport section such as two wheelers. The pressure regulator of the present disclosure further incorporates features that make it simple and easy to manufacture, maintain and service thus bringing further economy.

[66] As used herein, and unless the context dictates otherwise, the term "coupled to" is intended to include both direct coupling (in which two elements that are coupled to each other contact each other) and indirect coupling (in which at least one additional element is located between the two elements). Therefore, the terms "coupled to" and "coupled with" are used synonymously. Within the context of this document terms "coupled to" and "coupled with" are also used euphemistically to mean "communicatively coupled with" over a network, where two or more devices are able to exchange data with each other over the network, possibly via one or more intermediary device.

[67] It should be apparent to those skilled in the art that many more modifications besides those already described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the spirit of the appended claims. Moreover, in interpreting both the specification and the claims, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms "comprises" and "comprising" should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced. Where the specification claims refers to at least one of something selected from the group consisting of A, B, C ... . and N, the text should be interpreted as requiring only one element from the group, not A plus N, or B plus N, etc. ADVANTAGES OF THE INVENTION

[68] The present disclosure provides an efficient and cost effective pressure regulator for CNG for two wheelers.

[69] The present disclosure provides a pressure regulator for CNG for two wheelers that does not require heating of gas to offset cooling effect of its expansion.

[70] The present disclosure provides a pressure regulator for CNG for two wheelers that reduces number of assemblies, pipes and hardware in CNG installation kit.

[71] The present disclosure provides a pressure regulator for CNG for two wheelers that is not affected by cooling of gas due to pressure reduction/expansion.

[72] The present disclosure provides a pressure regulator for CNG that incorporates safety valve to protect from over pressure after reducing element.

[73] The present disclosure provides a pressure regulator for CNG that incorporates a filter at inlet port to prevent contaminants present in gas from entering area housing functioning parts and having narrow passages.

[74] The present disclosure provides a pressure regulator for CNG that incorporates a flow control valve which controls flow of gas in relation to suction vacuum.

[75] The present disclosure provides a pressure regulator for CNG that incorporates means to adjust engine idling speed and engine performance.

Claims

I claim:

1. A gas pressure regulator for a two wheeler comprising:

a first stage regulator for reducing gas pressure from a storage pressure to an intermediate pressure, wherein said first stage regulator comprises a cylindrical piston type reducing element that has a smaller end and a bigger end, and wherein pressure reduction in said first stage regulator is in ratio of area ratio of said bigger end and said smaller end, and further wherein said first stage regulator does not have any means of adjustment of output pressure; and

a second stage regulator, wherein said second stage regulator reduces gas pressure from said intermediate pressure to working pressure of less than 1 bar, wherein said second stage regulator is a diaphragm type regulator that regulates pressure in relation to atmospheric pressure to reduce said gas pressure to less than 1 bar.

2. The regulator of claim 1, wherein said first stage regulator further comprises a housing having an upper housing and a lower housing, wherein said upper housing incorporates an input port, and said lower housing incorporates an output port, wherein said housing has a cylindrical cavity having fluidic connectivity with said input port and said output port.

3. The regulator of claim 2, wherein said cylindrical piston type reducing element comprises a gas passage from said smaller end to said bigger end, and wherein said cylindrical piston type reducing element is housed within said cylindrical cavity in such a way that said smaller end is configured in said upper housing and said bigger end is configured in said lower housing.

4. The regulator of claim 2, wherein said first stage regulator further comprises a spring configured to keep said gas passage from smaller end to said bigger end of said cylindrical piston type reducing element unblocked but allow movement of said cylindrical piston type reducing element when force due to gas pressure on said bigger end exceeds combined force of said spring and force due to gas pressure on said smaller end and block said gas passage;

5. The regulator of claim 1, wherein said first stage regulator is housed in a first assembly and said second stage regulator is housed in a second assembly.

6. The regulator of claim 5, wherein said second assembly housing said second stage regulator also incorporates a flow control valve that regulates flow of gas to engine in relation to vacuum generated as a result of throttling action of two wheel driver.

7. The regulator of claim 6, wherein said second assembly housing said second stage regulator incorporates a solenoid valve between said second stage regulator and said flow control valve to control passage of gas.

8. The regulator of claim 1, wherein said first stage regulator does not get affected by cooling effect of expanding gas and does not need any heating means.

9. The regulator of claim 1, wherein said first stage regulator has input and output ports along longitudinal axis of said regulator.

10. The regulator of claim 1, wherein said first stage regulator incorporates a sintered material filter at input port, and an overpressure safety valve on output side.