MXPA97001498A - Both stages pressure regulator, better - Google Patents

Abstract

The present invention relates to a two-stage pressure regulator assembly, comprising: a) a regulator base comprising a first face and a second face, b) a first pressure chamber defined in the base, c) a second pressure chamber defined in the base and in pneumatic communication with the first pressure chamber, d) an input means defined in the base adapted to communicate with the high pressure fluid from an external supply to the first pressure chamber; an outlet means defined in the base adapted to communicate the regulated fluid from the second pressure chamber, at least one of the first inlet means and the outlet means that is defined by the first face, f) means adapted to avoid the flow of fluid out of the first pressure chamber at a pressure above a first predetermined level i) first valve seat means provided in the base ii) first valve means adapted to adapt The first valve seat means is provided when the first valve means is in the closed position thereby preventing fluid flow through the first pressure chamber, iii) first actuation means adapted to move the first valve means towards an open position when the flow pressure within the first chamber is below the first determined pressure level, and allowing movement of the first valve means to a closed position when the fluid pressure of the first valve means to a closed position when the fluid pressure is above the first predetermined level, the first activation means comprises: (a) a first diaphragm connected to the first valve means; (b) first spring means adapted to act together with the first diaphragm to the first valve means out from a closed position when the fluid pressure inside the first chamber is below the first pressure level predetermined; (c) means for retaining the first spring means in deviation relation with the first diagram; (g) means adapted to prevent fluid flow through the second chamber at a pressure above the second predetermined level comprising i) a second valve seat means provided in the base, ii) second valve means adapted to engage with the second valve seat means, when the second valve means is in a closed position, thereby preventing flow of fluid through the second pressure chamber, iii) the second activation means adapted to move the second valve means towards an open position, when the fluid pressure inside the second chamber is below the second predetermined pressure level and which allows movement of the second valve means towards a closed position, when the fluid pressure is above the first predetermined level, the second means activation comprises: (a) a second diaphragm connected to the second valve means; (b) a second spring means adapted to act together with the second diaphragm to deflect the second valve means away from a closed position, when the pressure of fluid within the second chamber is below the second predetermined pressure level, (c) means for retaining the second biasing spring means relative to the second diaphragm, and h) means adapted to communicate the temperature control fluid through the bladder. the base, the temperature control means has input and output ports, at least one of the input and output ports being defined by the first face, wherein at least one of the first activation means and the second means of activation are placed substantially in the second ca

Description

TWO-STAGE PRESSURE REGULATOR. IMPROVED DESCRIPTION The present invention relates to pressure regulators for various compressed gases and more particularly to pressure regulators used for gaseous fuels, such as compressed or liquefied natural gas. It has become increasingly common to use so-called alternative fuels, such as propane or natural gas, in internal combustion engines. Frequently such engines are converted to use one of two or more sources of fuel, such as gasoline and natural gas; the operator has the ability to switch between sources depending on the availability and price of these fuels. Almost all vehicles are manufactured to run on gasoline only and are converted to run on two or more fuels. The vehicles are manufactured with storage tank for gasoline, pumps to move gasoline from the tank to the engine and carburetors or fuel injectors to introduce the fuel and the required amount of air for combustion in the engine. Gaseous fuels such as propane and natural gas must be stored in pressurized cylinders to compress the gas into a manageable volume. Increasing the pressure to the highest level that can be safely handled by the pressurized storage cylinder increases the amount of fuel that can be stored in that cylinder and extends the distance the vehicle can be driven to its maximum. The typical storage cylinder pressures are in the range of 140.61 kg / cm2 to 351.53 kg / cm2 (2000 to 5000 psig). Internal combustion engines can not operate at such high pressure and the gas pressure must be reduced to a level at which the engine can be operated safely. The pressure must also be regulated as it is reduced to ensure that the fuel pressure entering the engine is constant even when the pressure in the storage cylinder is reduced. At the same time, the regulation of the pressure must allow as much gas as possible to be removed from the storage cylinder and in this way allow the pressure in the storage cylinder to decrease as close as possible to the operating pressure. A high pressure difference through the pressure regulating means, which remains unused fuel in the storage cylinder and is not available to the engine.

Conventional pressure regulators having one or more stages over which the pressure is reduced are well known and have been used for a long time to reduce the pressure and regulate the flow of compressed gases. Some of these are known as balanced regulators in pressure and the use of various arrangements of springs, diaphragms and machined parts to balance the pressures and fluid flow in various stages of the regulator. For example, the Patent of the United States No. 2,794,321 issued on June 4, 1957 to F.J. Warner et al. Describes a single-stage fuel pressure regulator, which is said to be useful in reducing and regulating the pressure of fuels such as propane to be used as fuel in an internal combustion engine. Some pressure regulators, such as those commonly used in compressed gas tanks, such as oxygen or acetylene, are designed to allow the operator to adjust the pressure drop across each stage. Others, such as those typically obtained in fuel supply systems, are pre-adjusted and do not allow for any adjustment or only "fine synchronization" by the operator, although more extensive adjustments can be made by authorized service people.

The pressure regulators of the prior art experience many disadvantages that the pressure regulator of the present invention is intended to overcome. One of the main problems is mentioned as "dejection" ie, the degree of uncertainty about the output pressure of the regulator. This insecurity is a function of the fuel flow velocity and the speed in the storage cylinder and creates problems, because the fuel injectors commonly used in modern vehicles are intended to operate at a constant fuel pressure. The previously proposed solutions involve the use of pressure and temperature shippers to detect variations in fuel temperature and pressure and make appropriate adjustments for [engine operation]. Another problem is the "slow movement", the increase in pressure inside the regulator and down the regulator, when the injector is off. Each increase in pressure makes it difficult to open the injector against the outlet pressure greater than that expected from the regulator. Associated with this increase in zero flow velocity pressure is the regulator's fuel leak. The flow of fuel to a pressure regulator is typically controlled by a solenoid controlled valve, which can be opened by the vehicle operator, just before the ignition system is ignited. The solenoid-controlled valve typically opens a pilot piston against cylinder pressure, which allows downward pressure to equalize upstream pressure. When the two pressures are close to equalizing, the primary piston opens to allow unrestrained fuel flow through the valve. In the prior art regulating assemblies, it may take several seconds for the desired operating pressure to be reached in the fuel injector. Unless the vehicle operator waits for this interval before ignition of the ignition, the vehicle can not turn on properly, or at all. The pressure regulator of the present invention provides an improved solenoid that opens quickly, independent of the pressure in the storage cylinder, thereby allowing the regulator to reach operating pressures almost immediately. Among other benefits of the improved pressure regulator of the present invention, there is a decrease in the minimum cylinder pressure, which can be achieved before refueling, an improved modular design that allows assembly in a variety of positions and orientations and a design of Improved filter that results in lower pressure drop across the filter and allows the filter to be cleaned or changed more easily. The improved pressure regulator of the present invention incorporates a new pressure relief valve, which can be manufactured by an inexpensive casting die to a similar technique of plastic or other inexpensive non-corrosive material. The present invention provides a two-stage regulator for regulating the pressure of compressed gases, such as natural gas used in vehicles powered by natural gas. The pressure regulator of the present invention is a strong, compact, high-flow regulator, low chill, low pressure drop and little slow movement, which is suitable for both OEM and for market use. It can be used by itself or with a third optional step to provide a three-stage regulator such as the atmospheric types (or zero pressure differences) commonly used to regulate the fuel pressure for gas carburetion systems. This is particularly useful in mono-, bi- and dual-fuel engine applications. The two-stage regulator of the present invention consists of a single base (the "regulating base") on which all the regulator components are mounted, including first and second stage spring towers regulators, a spring tower for a pressure safety valve (or PRV), a filter assembly, a high pressure solenoid activated valve and an optional cylinder pressure sender. The channels provided in the base, for example by machining allow the flow of refrigerant or other fluid through the base to control the temperature of the pressure regulator, and thus the outlet temperature of the gas flowing through it. The regulator components have new designs, which allow the regulator to achieve the objects of the invention. The improved two-stage pressure regulator design of the present invention provides a balanced design that minimizes variation in outlet pressure. In the regulators based on a spring diaphragm of the prior art, the outlet pressure is a function of a large number of variables, including the inlet pressure to the regulator, the outflow speed, the characteristics and properties of the diaphragm. , including its effective and stretched area, the reference pressure, the area and shape of the hole, the area and shape of the center pivot, spring speed and operating temperature. Balancing the regulator components minimizes the effect of several of these factors. Balancing the center pivot eliminates the effect of the inlet pressure, which is either the first or second largest contributor to the total abatement in the transfer function that determines the outlet pressure. In this way, balancing the regulator allows a much smaller regulator to achieve any given level of abatement. Smaller regulators respond more quickly and are cheaper to manufacture than large regulators. The improved design of the two-stage pressure regulator of the present invention uses anti-winding springs to improve the stability and response of the regulator and to allow the use of smaller spring towers. The design of the regulator involves choices to be made between conflicting items such as: size, cost, abatement, flow capacity, exit pressure, response time, stability, reliability, rigidity and appearance. As an example, the combination of orifice sizes, diaphragm areas, abatement levels, diaphragm reference pressures, spring speeds and double counterwash springs reduce the size of several key parts by 70%. These reductions improve the transient response, plus reduce the cost of the piece and the size of the package. Each of the first stage and the second stage of the regulator are designed to minimize the mass of the dynamic components, which in turn minimizes the inertia of these components during operation and allows the quickest response to changes in the operating conditions in the regulator. Each of the two stages uses two coil springs to minimize the spring constant and the height of the required spring tower. As explained in the following, these are believed to lead to minor "chill," or degree of insecurity of operating pressure. Of all the components of the first dynamic stage, with the exception of the center pivot, they can be constructed of aluminum, or other lightweight materials that have appropriate strength and thermal shock properties. A rotating diaphragm (preferably of a "top hat" type configuration further described in the following) is used in each of the first and second stages to maintain a constant effective area throughout the range of motion of the diaphragm. The rotating diaphragm of the present invention has greater durability and allows greater manufacturing tolerance than a flat diaphragm and to a greater extent eliminates the hysteresis effect of the flat diaphragms. A diaphragm of this configuration has an exceptionally long operating life and good performance in cold weather and durability.

In the regulator of the present invention, the spring tower of the first stage is sealed from the environment and referred to on the contrary to the pressure in the second stage. It has been found that it is not necessary to include an external pressure adjustment means in the first stage, since a variation of ± 10% in the pressure of the first stage will only result in a negligible variation in the outlet pressure of the regulator. Each of the first and second stages includes a central pivot assembly, which construction has been arranged to eliminate a potential leak path found in the prior art regulators (i.e., through the interior of the center pivot, the diaphragm, the diaphragm retainer assembly and inside the spring tower). Each center pivot has a snap-fit assembly that eliminates the risk of damaging the O-ring or other seal means. Each of the center pivots is manufactured from a material, which will withstand the pressures and potential corrosive forces to which it is exposed and which will provide an effective seal against upward pressures, when required. The center pivot of the first stage can be made of a hard plastic seal material (such as Zytel) which substantially eliminates the risk of any high pressure extrusion of the center pivot, which in any other way can occur with a seal of rubber. The plug of the central pivot cavity contains a ring at 0 in its base to eliminate the outgoing expansion; The depth of the thread can be calculated to withstand the pressure of more than 1404.14 kg / cm2 (20,000 psi). In one embodiment of the present invention, a molded rubber seal can be used for the central pivot seal of the second stage, since the seal is exposed to a maximum operating pressure of only 17.57 kg / cm2 (250 psig) and The high pressure extrusion of this material is not an interest. The use of a softer material in the lower pressure of the second stage, will significantly reduce to zero the slow motion flow. As explained in more detail in the following, the construction of the second stage regulator is substantially identical to the first stage, with the exception of the central pivot seal arrangement and the details of the construction of the spring tower. In the preferred embodiment of the present invention, shown in Figure 6, a molded rubber seal is used for the seal of the central pivot of the second stage, unlike the seal in the first stage, the seal is exposed to a maximum pressure of only 17.57 kg / cm2 (250 psig) and high pressure extrusion is not an interest. This approach dramatically reduces to zero the slow motion flow (pressure produced at rest) since it provides less leakage than a hard plastic seal (such as the Zytel brand material used in the first stage of the preferred embodiment). The spring tower of the second stage contains a pressure adjustment screw, which allows adjustment of the pressure in the second stage and thus the outlet pressure of the regulator when used alone and the supply for a plug to test of tampering, which can be installed after factory adjustment of the second stage. Each of the spring towers of the first and second stages are mounted on the base by conventional means, such as conventional fasteners (machine screws), or threaded fastening rings. The imbalances of different strength (due to different inlet pressures for the two stages) results in greater abatement in the first stage, but this is corrected in the second. The pressure regulator of the present invention is provided with a pressure safety valve, which is intended to operate in the event of a failure of the first regulating stage. In the case of such failure, the pressure of the gas entering the second stage would be substantially higher than normal. To protect the second stage and other components down from the effects of such high pressure, a pressure safety valve is provided between the first and second stages, which consists of a low mass piston, a PRV spring and a PRV tower. . The valve is designed to have an annular area around the piston, which is equivalent to the PRV orifice area. This allows the released pressure to act over a larger area once the predetermined pressure (the set point) on the PRV is reached and the piston exits its seat to release that pressure, thus forcing the piston to a wide opening and providing release of immediate pressure. It has been found that it is not necessary to provide any external adjustment to this predetermined pressure, since a variation of ± 5% at the set point is acceptable and will provide adequate protection for the regulator. The PRV tower is fastened to the base of the regulator by any conventional means, for example machine screws, which pass through a projection at the base of the PRV tower. The valve can be made with inexpensive die casting techniques, or by conventional machining methods, from non-corrosive materials such as aluminum or bronze. The outlet of the pressure of the safety valve can be vented to the atmosphere, to a collection chamber or recovery chamber.

A high-pressure shipper receptacle has been designed on the body to house an optional high-pressure shipper, which can be used to measure cylinder pressure. A pressure cap connects the hole to the high pressure bore down the high pressure solenoid, in such a way that a partial restriction for rapid pressure rise will occur when the "instant start" opens the solenoid (so which reduces the mobile contact and the speed of stamp in the sender). Accordingly, the high pressure shipper is only pressurized when the solenoid is energized and does not remain under pressure when the solenoid is closed. This prolongs the duration of the high-pressure shipper. The fuel inlet temperature information can be used in conjunction with the high pressure shipper, to provide a temperature compensated signal for the best fuel gauging safely. The fluid conduits control the temperature flowing around the outer perimeter of the body and are designed to provide heating to the base of the regulator and to the components mounted therein. The length of the total combined duct is designed to provide sufficient heat transfer to raise the gas temperature by 100 degrees Celsius to a maximum flow and cylinder pressure (approximately 2 kW of heat in some applications) and to compensate for heat loss as the gas expands. The modular construction of the present invention allows the use of gas high pressure conduits significantly greater than those in the regulators now in use and provides improved heat transfer from the refrigerant to the pressurized gas. The surface to volume ratios and an adequate thermal conductivity of the base material can be selected to provide optimum heat transfer designs. The cross-sectional area of the thermal fluid conduits can be minimized to allow minimal dispersion of the coolant flow of a motor. The design of the appropriate fluid conduits is believed to be within the skill of those in the art. A temperature detector at the outlet end can be installed in the upper part or the lateral surface in line, with the outlet duct between the spring tower of the second stage and the PRV tower. The controller design allows the installation of either or both of a fuel inlet or outlet fuel temperature detector. The temperature detector can be isolated from most of the heating effects of the regulating body, to allow an accurate measurement of the temperature of the fuel flowing from the cylinder. This temperature detector can be combined with the fuel pressure sender unit to provide a calibrated fuel temperature compensated signal. The described two-stage regulator is much more compact than the regulators now in use. The inlet, regulated outlet, PRV outlet and coolant inlet and outlet connections are on the front surface, allowing the unit to be mounted using any of the four remaining surfaces. The inlet projection of a modality of the present invention has been designed for a straight threaded 0-ring adjustment; the remaining adjustment projections have been designed for 45 degree flared accessories, thus allowing maximum adjustment rotation and maintaining mounting options. Other types of adjustments can be selected and used with little or no change in the outgoing. In operation, the pressurized natural gas, which can be at a pressure of 8.43 kg / cm2 and up to 351.53 kg / cm2 (120 psig and up to 5,000 psig), enters the regulator and passes through the filter to the first stage of the regulator. It passes up through the hole in the center pivot. The springs of the first stage act against the gas pressure to keep the orifice in an open position, regulating the gas flow of the pressurized storage cylinder within the first stage of the regulator. The pressure is reduced to approximately 8.43 kg / cm2 - 17.57 kg / cm2 (120-250 psig). From the first stage, the gas passes through a transfer conduit to the second stage. Connected to this transfer conduit is a conduit for the pressure safety valve, which as mentioned above, is intended to open in the event of a failure of the first stage of the regulator, to protect the components down from high pressure of gas without regulating. From the transfer duct, natural gas flows up through the hole in the central pivot in the second stage of the regulator; in the second stage, the pressure is reduced to approximately 7.03 kg / cm2 (100 psig) (or such other pressure as should be chosen and maintained by the appropriate spring speed selections generally in the range of about 3.51 kg / cm2 to 10.54 kg / cm2 (50 to 150 psig)). The towers of the first and second stages, the pressure safety valve, the fuel storage pressure sender, the filter and the high pressure solenoid towers are all of similar height resulting in a substantially rectilinear and compact, total configuration, which facilitates the use of a modest / environmental cover. The two-stage pressure regulator of the present invention described has several benefits over previously known regulators, which are produced from its novel structure. It results in less abatement or "degree of insecurity about the operating pressure". There is less leakage when natural gas fuel is not being used. The improved design results in slower movement or "increase in pressure above the nominal" when the injectors are turned off and there is no demand for pressurized gas. The modular construction provides adjustment flexibility and reduced size, with increased mounting options. The pressure regulator of the present invention requires a lower inlet pressure to operate and can operate at a cylinder pressure as low as 100 psi. In this way, more fuel in the fuel cylinder can be used before filling. Conventional pressure regulators operate only below a cylinder pressure of 14.06 kg / cm2 to 17.57 kg / cm2 (200-250 psig). The regulator provides better transient response, due to the design of lower abatement and the use of light weight components, which results in a more uniform operation.

The regulator is capable of providing different output pressures, while maintaining low chill, making changes to the springs or pre-adjusted tension in the spring towers of the first and / or second stage. Finally, the regulator provides a balanced second stage for even lower abatement, with the consequent risk of reduced leakage. The design of the present invention allows these components to be assembled in a relatively small and compact unit. From a review of the more detailed description provided in the following, it will be appreciated that the design of the high pressure detector of the solenoid assembly will be useful in other applications and can be used, for example, as: • a natural gas switch solenoid in line; • a solenoid switch in the cylinder; • A solenoid switch of the cylinder filling system in line, when added to the features that include, filtration, pressure and temperature detection, pressure safety valve, gas inlet and outlet accessories, manual bypass and with a ventilation distributor; • a refueling station for the natural gas vehicle mounted on an automatic valve; • an automatic Emergency Shut-off valve in refueling stations of the natural gas vehicle; an automatic inter-stage valve in the compressors of the natural gas refueling station, and • a solenoid switch at the filling point in combination with the refueling receptacle. BRIEF DESCRIPTION OF THE DRAWINGS FIGURE 1 is a perspective view of a pressure regulator according to the preferred embodiment of the present invention, showing the top, front and one side of the regulator. FIGURE 2 is a perspective view of a pressure regulator according to the preferred embodiment of the present invention, showing the lower, rear and one side of the regulator. FIGURE 3 is a top plan view of a pressure regulator according to the preferred embodiment of the present invention. FIGURE 4 is a vertical cross-sectional view of the pressure regulator of FIGURE 3, taken along line 4-4 in FIGURE 3, showing the first and second stages of the regulator in a sectional view. FIGURE 4A is a vertical cross-section of another preferred embodiment of the present invention, having a second-stage configuration balanced in the pressure. FIGURE 5 is a partial sectional view of the central pivot assembly of the first stage of the pressure regulator shown in FIGURE 4. FIGURE 6 is a partial sectional view of the central pivot assembly of the second stage of the regulator of FIG. the pressure shown in FIGURE 4. FIGURE 7 is a vertical, cross-section of the pressure regulator of FIGURE 3, taken along line 7-7 in FIGURE 3 showing the second stage and valve assembly of regulator pressure safety of the preferred embodiment of the present invention. Figure 7A is a horizontal partial section of the pressure regulating piston shown in FIGURE 7 taken along the line 7A-7A. Figure 8 is a partial sectional view of the input filter area NGV, taken along section lines 8-8 in FIGURE 3, showing the filter assembly of the preferred embodiment of the present invention. FIGURE 9 is a partial sectional view of the high pressure solenoid of the preferred embodiment of the present invention, taken along section lines 9-9 shown in Figure 3.

FIGURE 10 is a sectional view of the pressure sender assembly. FIGURE 11 is a schematic representation of a preferred embodiment of the invention. With reference to Figures 1 and 2, the present invention, in its preferred embodiment, consists of a two-stage regulator consisting of a base or housing 100 in which they are formed, by drilling or in any other form, many orifices and channels, described in more detail in the following. In housing body 100 there is a plurality of mounting holes 102 placed on up to 4 of the surfaces on the base thereby providing greater flexibility in selecting how the assembly can be installed in a desired application. A plurality of plugs 104 are also provided for closing the openings formed by drilling holes or test sites producing natural gas communications, as well as channels for communicating the temperature control fluid within the housing. In the housing, there is a filter assembly 200, a control tower of the first stage 500, an instantaneous ignition assembly 300, a control tower 700 of the second stage, a pressure relief valve assembly 600 ("PRV ") and a mounting cylinder pressure detector 400.

In the housing there are openings 162 for the inlet of the fluid that control the temperature and 164 for the outlet of the fluid for the control of the temperature and the openings 103 and 106 for the entry and exit, respectively, of natural gas or another fluid whose pressure is to be regulated. Figure 2 shows a different perspective view of the two-stage regulator assembly of the present invention, showing the lower and rear surfaces of the base and the location of the cavities formed therein for the first and second stages of the regulator assembly. The plug 107 of the cavity of the first stage and the plug 108 of the cavity of the second stage are shown installed in the base to seal the openings formed during the perforation of the portions of the two pressure chambers. Figure 3 shows a top plan view of the pressure regulator of the present invention, including the filter assembly 200, the instantaneous ignition solenoid valve assembly 300, the optional cylinder pressure detector assembly 400, the regulator tower 500 of the first stage, the pressure safety valve 600 and the regulating tower 700 of the second stage. With reference to Figure 4, a cross section of the pressure regulator of Figure 3 taken along line 4-4 of that Figure, can be observed. Figure 4 illustrates the internal structure and mechanism of the first and second stages of the two-stage regulator, specifically illustrating the spring towers of the first and second stages, the central stem assemblies of the first and second stages, which are describe in more detail in the following and the passages through which the fluid controls the temperature and regulated gas flow. As shown in Figure 4, the spring tower 500 of the first stage comprises a cover 502 of the spring tower, which has an upper wall 503, side walls 504 and a lower projection 505. Between the upper wall 503 and the upper walls 503. side walls 504 there is a projection 506 and on the underside of the upper part 503 there is a projection 507 adapted to receive the spring 510, as described in the following. As described in greater detail in the following, the orifice of the spring tower is larger than the outlet chamber 116 of the first stage, thereby forming a rim 117 to prevent the diaphragm piston 554 from sliding to the diaphragm if the pivot fails. central. Within the spring tower of the first stage are the springs 510 and 512, the spring 512 is positioned outside the spring 510 and the springs are wound in opposite directions. The spring constants are selected to give the desired output pressures. Springs with different spring constants can accommodate different outlet pressures. The projection 507 is of such dimension that it fits within the internal diameter of the first helical spring 510 and the projection 506 is adapted to receive and retain the outer helical spring 512. The cover of the spring tower 502 is adapted to be mounted on the base 100 by means of mounting bolts or other fastening mechanisms, not shown. For example, tamper-proof screws or other means may be used to secure the projection 505 to the base of the regulator assembly 100. Referring to Figure 4, there is shown a spring tower of the second stage 700 consisting of a cover of the spring tower 702, which has an upper surface 703, side walls 704 and a lower projection 705. Between the side walls 705 and the upper surface 703 there is a projection 706. The pressure inside the tower of the second stage sent to the atmosphere through a hole or opening in the cover 702 or in some other convenient location. Within the spring of the second stage of the pressure regulator is a central pivot arrangement of the second stage, shown in greater detail in FIG.

Figure 6. A clamping ring 707 is provided to secure the second mounting of the spring tower to the base. Included within the second assembly of the spring tower are the first and second coil springs 710 and 712 respectively, which are wound in opposite directions. The upper ends of the springs 710 and 712 abut against a spring that adjusts the end cap 720, which can be displaced in a vertical direction by means of a set of adjusting screws 722 thus allowing an adjustment of the force exerted by the springs 710 and 712 against the pivot mount 750. The set of set screws is protected against unauthorized adjustment by an undue driving proof means 724, using any of the various known tamper-evident means. The orifice of this spring tower is also larger than the orifice of the corresponding outlet chamber, to prevent the diaphragm piston from moving to the diaphragm if the center pivot fails. The tower assemblies of the first and second stages each use two coils wound in opposite fashion to minimize the height of the tower and the spring constant. By reducing the spring rates for a given tower height, this spring configuration leads to a lower degree of uncertainty of the operating pressure ("chill"). The reverse winding of the springs minimizes the risk that the coils of the adjacent springs will become intersubject during the movement of the springs.

With reference to Figure 5, the central pivot arrangement of the first stage consists of a diaphragm 552 generally positioned in a horizontal direction, but having a rotating convolution 510 that extends upwardly of the diaphragm 552 to provide a modification in the behavior of the diaphragm. Specifically, this design ensures that the diaphragm is always in tension (ie never in shear or pressure). In this way, as the convolution rolls the diaphragm is never stretched or warped (ie the hysteresis is greatly eliminated). In addition, this configuration of the diaphragm essentially provides areas of constant work without considering the diaphragm, the stroke, that is, the displacement of the diaphragm from its fundamental position. As mentioned in the above, the presence of the rotating convolution provides many advantages, including increased longevity in the working life of the diaphragm and allows greater tolerances in the manufacture of the diaphragm. The rotating convolution also eliminates the hysteresis effect found in any other form on a flat diaphragm during the operational displacement of the diaphragm. In yet another preferred embodiment, a "top hat" style diaphragm (not shown) with a larger convolution can be used in place of a diaphragm with a preformed convolution. This can be used to minimize variation in the diaphragm area, which can occur in any other way with changes in the position of the pivot mountings. The diaphragm 552 is mounted on a lower diaphragm retainer 558, which has an outer edge 512 rotated downwardly and the central projection extending through the center of the diaphragm 552. The diaphragm is retained on the lower diaphragm retainer by means of of a diaphragm piston 554 and a clamping ring 562. A spring damper 564 is retained between the clamping ring 562 and the outer circumference extending upwardly of the piston of the diaphragm 554. The spring damper 564 strikes the walls 504 (shown in Figure 4) of the spring tower, but can be moved along the walls during movement of the pivot assembly of the first stage and serves to minimize the oscillation of the spring assemblies during fluctuations in fluid pressure. In a version of the preferred modality, the spring absorber comprises eight fingers that extend upwards each one against the side walls 504 (shown in Figure 4). A shock absorber having eight fingers in many cases will provide a better distribution of force on the side walls than for example, a shock absorber having only four fingers, thus resulting in a reduced tendency of the fingers to wash on the side walls. Mounted within the central projection of the lower diaphragm retainer is a rod 565 of the central pivot, which may have a narrow central portion and a head 566, which is retained in place on the projection 560 by a retainer 568 of the central pivot. At the lower end of the central pivot arrangement of the first stage there is a central valve pivot 570, threadedly engaged on the rod 565 of the central pivot. Around the central valve pivot there is a valve pivot seal 572, which is maintained in an arrangement sealed with the valve stem 570 by means of a ring in 0 574. If desired, a Teflon washer can be added (not shown ") between diaphragm 552 and diaphragm piston 554 to provide increased protection during cold weather.Teflon washer will slowly decrease heat transfer to diaphragm 552. Alternatively, diaphragm piston 554 and lower diaphragm seal 558 can provided with a ceramic coating to provide such enhanced performance during cold weather.In addition, the configuration of the spring tower chamber (shown in Figure 4 at 513) can be altered to provide a "dead gas" trap ( not shown) between the diaphragm 552 and the lower retainer 558 to increase the operation in the cold climate Now with reference to Figure 6, the device The central pivot assembly of the second stage is in many respects similar to the central pivot assembly of the first stage. The central pivot assembly of the second stage consists of a diaphragm 752 generally positioned in a horizontal direction, but having a rotatable convolution 711 extending downwardly from the diaphragm 752 to provide a modification in the behavior of the diaphragm. The diaphragm 752 is mounted on a lower diaphragm retainer 758, which has an outer edge 713 rotated downward and the central projection 760 extending through the center of the diaphragm 752. The diaphragm is retained in the retainer of the lower diaphragm by means of a diaphragm piston 754 and a clamping ring 762. A spring damper 764 is retained between the clamping ring 762 and the vertically extending outer circumference of the piston of the upper diaphragm 754. The spring damper 764 impacts against the side walls 704 of the spring tower (shown in Figure 4) but can be moved along the walls during movement of the central pivot assembly of the second stage.

Mounted within the central projection of the lower diaphragm retainer is a rod 765 of the central pivot, which may have a narrow central portion and a head 766 which is held in place on the projection 760 by a fastener of the central pivot 763. At the lower end the central pivot arrangement of the first stage is a central valve pivot 770, threadedly engaged on the rod of the central pivot 765. Around the central valve pivot there is a molded rubber seal 774. The pressures of significantly lower fluids in the second stage pressure chamber, allow the use of a molded rubber seal with little risk of seal deformation, which can occur in any other way in the presence of higher fluid pressures more commonly encountered in the pressure chamber of the first stage. If desired, a Teflon washer can be added between the diaphragm 752 and the diaphragm piston 754 to provide increased protection during cold weather. The Teflon washer will slowly decrease heat transfer to the diaphragm 752. Alternatively, the diaphragm piston 754 and the lower diaphragm retainer 758 can be ceramic coated to provide such operation in increased cold weather.

In addition, the configuration of the spring tower camera (at 714) may be altered to provide a "dead gas" trap between diaphragm 752 and lower detent 758 to increase cold weather operation. As mentioned in the above, the mounts of the pivot of the second stage are a bit similar. Some components can be interchangeable to minimize manufacturing, storage and other costs associated with the use of different parts. For example, in the preferred embodiment, the diaphragms 552 and 752, the diaphragm pistons 554 and 754, the diaphragm detents 558 and 758 the fastening rings 562 and 762, the spring bumpers 564 and 764 and the pivot fasteners 568 and 763 have the same specifications and are otherwise interchangeable for use in any of the pivot assemblies of the first or second stage. Referring again to Figure 4, the fluid under pressure enters the housing through the inlet 103, shown in Figure 1 and passes through the filter assembly described in greater detail in the following. The fluid enters the first stage of the pressure regulator through the inlet 152, into the chamber of the central pivot 154 of the first stage, which is essentially at the pressure of the gas storage cylinder. The fluid passes in a controlled manner through the space between the center pivot seat 572 and the walls of the central pivot chamber 114 and then through the pressure recovery section 112 of the first stage. Fluid flow is regulated by the combined force exerted by springs 510 and 512 and diaphragm 552 (shown in Figure 5), which tends to move the center pivot assembly to an open position, while fluid pressure in the chamber 154 of the central pivot act against the diaphragm 552 (shown in Figure 5) tends to move the central pivot to a closed position. The chamber 154 of the central pivot has an integral downward protection shroud 155 to prevent excessive oscillation of the gases flowing through the chamber. The diverter plate reduces the pressure drop in the gases flowing through the chamber, thus allowing the operation of the regulator at lower supply pressures. The diaphragm 552 (shown in Figure 5) provides a seal against gas escape upwardly through the first stage tower and allows uniform vertical movement of the center pivot between the closed and fully open positions. A flange 117 is provided along the circumference of the exit chamber 116 of the first stage to make butt contact against the curved edge downwardly of the lower diaphragm retainer to prevent opening of the first stage valve assembly beyond a selected distance. To further improve the high flow characteristics, the exit chamber of the first stage includes an inclination 118 to create a more uniform transition between the exit chamber and the channel communicating with the second stage. The retainer 558 of the lower diaphragm, as shown in Figure 5, defines the upper wall of the exit chamber 116 of the first stage. The regulated fluid in the first stage passes through the pressure recovery section 112 of the first stage to the outlet chamber 116 of the first stage. The fluid then passes through the transfer conduit 159 from the first stage to the second stage, to the chamber 180 of the central pivot of the second stage. Again, the fluid passes through the available space between the central pivot seal of the second stage, a molded rubber seal 774 and the projections 126 of the second stage formed as an integral part of the base. In one embodiment, the radius of curvature of the protrusion 777 in the molded rubber seal 774 (shown in Figure 6) is selected to complement the radius of curvature in the protrusion 126. The complementary radii can be used as a means of substantially increase the discharge factor of the gases that flow by reducing the turbulence and pressure drop in those gases. The curvature of the ribbon in the rod 765 of the central pivot may be mixed with the curvature of the molded cup seal 774 to further decrease the tendency for pressure drop in this area. The flow of fluid through the chamber of the second stage is regulated by the combined force exerted by the springs 710 and 712 and the diaphragm 752 (shown in Figure 6), which tend to move the central pivot assembly of the second stage towards an open position. The fluid pressure in the chamber 180 of the central pivot acting against the diaphragm 752 (shown in Figure 6) provides an opposite force, which tends to move the central pivot of the second stage to a closed position. The diaphragm 752 provides a seal against fluid leakage through the second stage tower and allows a uniform vertical movement of the central pivot of the second stage between the closed and fully open positions. The lower diaphragm retainer 758, as shown in Figure 6, defines the upper wall of the upper portion 216 of the exit chamber of the second stage. A flange 717 is provided in the outlet chamber 216 to engage the outer edge 713 of the lower diaphragm retainer 758 and thereby prevent displacement of the central pivot assembly of the second stage beyond a set point. The exit chamber of the second stage incorporates a spiral ramp (not shown) to further reduce the abatement. The ramp generates higher gas velocities and a more uniform transition to the exit. The ramp can be incorporated into the base using forging techniques, which are typically less expensive than machining. The regulated fluid then passes through the outlet conduit 156, which communicates with the outlet opening 106, shown in Figure 1. A removable end cap 580 is provided to enclose the lower portion of the center pivot chamber 154. of the first stage. The end cap 580 can be removed to access the central pivot chamber of the first stage for assembly, maintenance, or inspection of the interior work portions. End cap 580 also provides centering for the center pivot. A ring 582 at 0 sits intermediate the base of the regulator 100 and the end cap 580 to provide a seal against leakage of fluid that passes to the end cap 580. Similarly, a removable end cap 780 is provided. to enclose the lower portion of the chamber of the central pivot 180 of the second stage. A corresponding O-ring 782 is provided to form a seal between the base of the regulator 100 and the end cap 780 of the second stage.

Figure 4A shows still another preferred embodiment of the present invention, which comprises modifications to the central pivot chamber of the second stage, the central pivot of the second stage and the related elements. In particular, a central pivot arrangement balanced in the pressure is described as an alternative means of reducing chill in the regulator. By using the balanced pressure configuration, it is possible to eliminate the use of complementary radii in the configuration of the central pivot and the corresponding hole defined by the projection 126. In addition, the need for spring absorbers will be eliminated in many cases, due to the damping characteristics of the present modality. With reference to Figure 4A, a central pivot 770 of the second stage has a rubber seal 799 secured on its surface proximate the bore defined by the projections 126. The lower portion of the central pivot defines a channel for retaining a ring seal 793 in O. The seal 793 is coupled with a floating seal member 792 formed in a cup to form a substantially gas-tight fit. The central pivot can slide vertically with relative freedom within the housing formed by the floating seal 792. The floating seal 792 is restricted against any substantial vertical displacement, by means of a fastener with projections 791. However, a relatively small vertical space is provided. between the bracket with projections 991 and the float seal 792 to allow the sliding lateral movement of the seal 792 in relation to the end cap and the fastener. It can be understood that the present configuration can be manufactured using lower cost techniques that have higher tolerances. The bracket with projections 791 may be secured to the end cap 790 by threaded means or other suitable means. The lower portion of the center pivot 770, the floating seal 792 and the ring seal 793 in O, define a chamber 796 which communicates with the second chamber of the central pivot of the second stage by means of a channel or hole 795. orifice 795 has an inlet 798 to the second chamber of the center pivot. The inlet 798 is defined by the rubber seal 799. It can be seen that the pressure differences between the gas reservoir 796 and the second center pivot chamber, will act to a certain extent on the force exerted by the spring assembly. That is, under a condition of reduced pressure in the second chamber of the central pivot, under a condition of increased pressure in the reservoir 796, the springs will hang to open the central pivot additionally, thereby causing the gas in the reservoir 796 to come out at the central pivot chamber via channel 795. At the same time, by counteracting the pressure of the gas remaining in reservoir 796, it will act to dampen the force exerted by the springs, when they act to move the central pivot further to the open position. In circumstances in which the pressure in the central pivot chamber is greater than in the reservoir 796 and with the tendency of the high pressure gas in the central pivot chamber to move the central pivot to the closed position, the lower relative pressure within of the reservoir will counteract to some extent that force and reduces the tendency of the central pivot to move to the closed position. Figure 7 shows the regulator tower assembly 700 of the second stage and the pressure relief valve assembly 600 of the preferred embodiment of the present invention. The PRV assembly is mounted above the PRV chamber 603 in the base 100 (shown in Figure 1) of the pressure regulator. The PRV chamber 603 formed in the base of the regulator 100 (shown in Figure 1) has a lower portion 605 connected by the conduit 654 to the upper portion of the cavity 116 of the first stage (shown in Figure 4). The upper portion 607 is of a greater cross section than the lower portion 605, forming a pedestal 608 on which the piston 625 PRV is retained. The PRV assembly consists of a housing 610 which connects at its lower end with the PRV chamber 605. The housing defines an outlet cavity 611, a narrow outlet throat 612 and a widened opening 614 through which any of the ventilated gases they can pass into the atmosphere through the exit opening 130 PRV. The housing 610 has a base with protrusion 616 on which a gasket 636 sits. The gasket 636 provides a gas-tight seal between the housing PR10 and the base of the regulator 100 (shown in Figure 1). Within the PRV assembly there is a helical spring 620 positioned between the upper end of the housing 610 and a PRV 625 piston. Mounted on the underside of the PRV 625 piston is a seal 640, which is adapted to maintain a pressure-tight seal on the PRV 625 piston. the PRV 605 camera under normal operating conditions. The characteristics of the spring 620 must be selected to provide the desired pressure relief setting for the exhaust over the pressurized fluid of the assembly to protect the components of the second stage of the damage regulator assembly. It is understood that the overpressured fluid will cause the PRV piston to be displaced upward by the action against the force of the spring and compressing the spring to allow the overpressure fluid to escape into the outlet cavity 611 and then exit through the outlet opening. 130. Once the pressure in chamber 605 falls below that of the force exerted by spring 620, the PRV will reset again providing a pressure-tight seal. As shown in Figures 7 and 7A, the PRV piston 625 consists of a cylindrical, hollow central portion 632 adapted to receive and engage the lower end of the coil spring 620. The PRV piston is preferably made of a material resistant to corrosion, lightweight (for example, plastic). Positioned around the central cylindrical portion 632 is a plurality of fins 634, which slidably engage the walls of the upper section 607 of the PRV chamber 603. The fins are provided to promote the sliding movement of the piston along the lengths of the piston. Upper section walls and minimize the risk of the piston becoming stuck against the walls. Figure 8 shows a partial section of the NGV input filter area of the regulator assembly. A filter cover 260 is placed in the groove of the upper filter 230 formed in the base of the regulator 100. An O-ring 261 is provided to form a seal between the abutting contact surfaces of the filter cover and the base 100 for Minimize the expansion of the outgoing. A corrugated washer 264 hits the filter cap 260 and exerts a downward force on the input filter 262. The filter cap 260 can be easily removed and subsequently re-insured to facilitate the replacement of a clogged inlet filter without being required the disconnection of the input accessory. The inlet filter 262 is of a generally hollow cylindrical construction. The effective surface area of the filter element is greater than that of conventional filters. The effective surface area is formed of a substantial portion of the end surface 268 of the filter (which is not covered by the corrugated washer 264) and substantially of the entire circumferential area of the outer filter wall 269. A surface area The larger filter allows higher fluid flow rates with significantly lower pressure drop across the filter. A larger filter area also reduces the opportunities for filter plugging and the frequency resulting from filter changes in the preferred embodiment, the input filter 262 is sized at 40 microns and is made either of sintered stainless steel, sintered bronze, or sintered brass material. The lower end 263 of the inlet filter 262 is seated by snap fit into a groove 235 formed in the base of the regulator 100. An inlet projection 240 NGV is provided in the base 100. The projection 240 contains the inlet 103 NGV which communicates with an input channel 250. The input channel 250 communicates with the outer filter chamber 222 found in the intermediate part of an outer wall defined by the filter cover 260 and a groove 259 formed within the base of the regulator 100 and the outer porous wall 269 of the inlet filter 262. A slot 257 formed in the base 100 together with the inner surface of the inlet filter 262 defines an inner filter chamber 265. The outer filter chamber 222 communicates with the inner filter chamber 265 through the microscopic passages of the inlet filter. From the above description, it can be seen that the inlet fluid flows through the inlet opening NGV and through the inlet channel 250. The fluid enters the outer chamber 220, which surrounds the outer wall 269 of the inlet filter , impurities are retained on the outer surface of the inlet filter and thus are removed from the fluid. The filtered fluid passes into the inner filter chamber 265 and then flows through a connecting conduit 266 into the high pressure solenoid chamber and over the regulator assembly of the first stage. Figure 9 shows a high pressure solenoid assembly 300 mounted on the base of the regulator 100. The solenoid assembly can be detachably secured to the base of the regulator by means of screws or a threaded fitting for removal and replacement when desired. The solenoid assembly consists of a housing 310 supported on a solenoid base 331. The solenoid base 331 is housed in a pilot piston cavity 307 in the base of the regulator 100. An O-ring 309 is provided to seal the connection seal between the solenoid assembly and the base of the regulator 100. The solenoid housing contains a coil 308 connected to a power supply 302 and held to the housing 310 by means of a retaining screw 305. The coil 308 is of a relatively small construction providing a Compact design adapted for use in high fluid pressure applications. Since this design requires relatively low amounts of magnetic force to be developed, the coil is physically smaller (less expensive, lighter weight, easier to pack) than with other historical designs and requires less electrical power to operate the solenoid ( resulting in greater efficiency, lower heat generation). The solenoid coil extends up and out of the base of the regulator 100. The pilot piston 306 extends upwardly from within the solenoid base 331 upwardly into the cavity surrounded by the solenoid coil 308. An end cap 320 of the primary piston cavity is secured to the base of the regulator 100 by a threaded coupling means. An O-ring 322 provides a leak-proof seal between the end cap 320 and the base of the regulator 100. The cavity 351 of the primary piston is defined by the regulating housing 100 and the end cap 320. The piston cavity Primary 351 houses the primary piston 379 used to turn the fluid flow on and off in the first stage of the regulator assembly as described in greater detail in the following. The fluid flows from the filter assembly through the conduit 266, which communicates with the primary piston cavity 351 when the primary piston is in the "on" position and thus allowing the fluid to flow along the length of the piston. connection channel 152 to the pivot chamber of the first stage. In the preferred embodiment, the instantaneous ignition solenoid includes a solenoid operated by a pilot piston 306, which seals against a small pilot hole 373 and a primary piston 379, which seals the main flow port 376. The primary piston 379 contains a low friction seal ring 362 (Teflon type), which seals the piston in the hole, while allowing movement and providing coulomb damping of any of the primary piston oscillations. A small extraction hole 375 (smaller in diameter than the pilot orifice) is incorporated in the primary piston, which allows a controlled leakage rate through the piston. In addition, the primary piston contains a tapered head seal that retains the screw 377, which fits intimately into the primary orifice. The retaining screw prevents extrusion of the primary orifice seal 381, when the supply pressure is high and reduces the oscillations of the primary piston by limiting the flow in the low piston strokes. The pressure is communicated from the pilot piston cavity to the primary piston cavity by the bore 371. From this description, it will be understood that a pneumatic coupling is provided between the primary and pilot pistons, thereby allowing the construction of a solenoid assembly dimensionally substantially smaller and one of lower cost compared to the typical solenoid assemblies that characterize electromagnetic couplings. As shown in Figure 9, the channel 152 is provided with a venturi 144 to further reduce the pressure drop in the gases flowing past the primary piston, particularly at high flow rates. In the "off" position, the spring 382 returns to the pilot, forces the pilot piston 306 to seal against the pilot piston bore 373. The pressure of the conduit 266 then communicates to the rear side of the primary piston 379 via the opening 375 and the same through the primary piston. The return spring of the primary piston 380 then forces the primary piston to seal against the primary orifice. In the "on" position the pilot piston is retracted by the solenoid coil allowing fluid to flow into the channel 152 from the cavity 378 of the pilot piston. The fall in the resulting pressure is communicated to the back side of the primary piston 379 by means of bore 371. The resulting pressure difference acting on the primary piston exceeds the force of the return spring and the difference of the orifice causing the primary piston open If an instantaneous ignition solenoid assembly is not required or desired for a particular regulator mount, the pilot piston cavity 378 may be omitted and the primary piston plug 379 may be replaced with a conventional expansion plug. In other applications where a high pressure solenoid is not desired, a conventional two stage solenoid may be installed in the primary piston cavity with the coil and solenoid housing extending outward from the front surface 191 of the regulator base. . A high pressure shipper (not shown in detail) can also be provided to measure the pressure of the feed cylinder, if desired. For example, in some applications, a high pressure shipper can not be required as a component of the regulator assembly, particularly where the pressure delivery means immediately exists to the high pressure fluid supply cylinder. In the preferred embodiment, a pressure sender assembly 400 is shown in Figure 10. A high pressure sender orifice 1001 has been provided in the base of the regulator 100 to accept a pressure sender assembly. A pressure measuring plug 1002 or channel connects the dispensing opening 1001 to the high pressure connector channel 152 down the high pressure solenoid assembly. The small space between the male threads of the pressure sender 400 and the female threads of the pressure-releasing orifice 1001 form a helical space along the helical length of the screw threads, forming a distributed hole 1003, which represents a partial restriction on the rapid pressure rise, which occurs when the high pressure solenoid opens. This results in less extreme rates of change in the pressure at which the pressure shipper is exposed, tending to increase and prolong its expected work duration. Figure 11 shows a schematic representation of the preferred embodiment of the present invention adapted to be used in association with a supply of natural gas used to operate a motor vehicle. In many motor vehicle applications, operating cylinder pressures will typically start at pressures of up to 316.3-8 kg / cm2 (4500 psig). It should be understood by those skilled in the art that embodiments of the present invention can also be adapted to withstand input pressures as high as 351.53 kg / cm2 (5000 psig). In the use of one embodiment of the present invention, it must in many cases be possible to operate the motor vehicle until the cylinder's gauge pressure falls to approximately 8.43 kg / cm2 (120 psig). It is noted that conventional two-stage pressure regulators require a minimum of approximately 14.06 kg / cm2 to 31.63 kg / cm2 (200 to 450 psig) of cylinder pressure to continue the operation. Therefore, it can be appreciated that the ranges of operation may be increased using the embodiments of the present invention. With reference to Figure 11, a dotted outline encloses the elements of the preferred embodiment. On the outside of the two-stage regulator there is a fuel inlet source supplying high-pressure fuel to the inlet filter, an electronic control module used to control the instant-on solenoid and the high-pressure sender and the coolant inlet and exit lines to circulate the fluid that controls the temperature through the base of the regulator. Shown to the right of the schematic and exterior drawing of the dotted representation of the regulator are a PRV output fitting and a FUEL OUTPUT representing the regulated pressure natural gas supply to supply to the power plant of the vehicle. As mentioned above, the high pressure natural gas flows through a 40 micron filter, when the instant ignition solenoid is in the open position according to the signals received from an electronic control module. The pressure of the inlet filter gases flowing through the solenoid are measured by a high pressure sender located intermediate the instantaneous ignition solenoid and the first stage assembly. The high pressure gas flows into the first stage of the regulator and exits at 10.54 kg / cm2 to 17.57 kg / cm2 (150 to 250 psig) (during normal operating conditions) for the supply to the second stage assembly . The pressure release valve (PRV) is connected to the intermediate fluid flow path of the first and second stages to release the overpressured natural gas flowing from the first stage in excess of a predetermined setting of 22.84 kg / cm2 ( 325 psig). That is, the PRV will open to allow the overpressurized gas to escape to protect the second stage components from the effects of excessively high gas pressures. The natural gas that leaves the assembly of the first stage, will rise to the assembly of the second stage for the regulation of the additional pressure that results in a fuel outlet flow that occurs at a pressure of approximately 7.0 kg / cm2 (100 psig) (or other pressure that must be selected and provided by the spring elections). The schematic representation also illustrates that the pressures of operation of the PRV and the assemblies that regulate the pressure of the second stage refer to the atmospheric pressure. Nevertheless, the operating output pressure of the first stage assembly is sent to the outlet pressure of the second stage assembly during normal operating conditions.

Claims (22)

1. CLAIMS 1. A two-stage pressure regulator assembly comprising: a) a regulator base; b) a first pressure chamber defined in the base; c) a second pressure chamber defined in the base and in pneumatic communication with the first pressure chamber; d) an input means defined in the base adapted to communicate with the high pressure fluid from an external supply to the first pressure chamber; e) an exit means defined in the base adapted to communicate the fluid regulated in the pressure from the second pressure chamber; f) means adapted to prevent fluid flow out of the first pressure chamber at a pressure above a first predetermined level; g) means adapted to prevent the flow of fluid through the second chamber at a pressure above a second predetermined level: characterized in that: h) the means adapted to prevent the flow of fluid out of the first chamber comprise: i ) first valve seat means provided in the base; ii) first valve means adapted to engage with the first valve seat means, when the first valve means is in a closed position, thereby preventing the flow of fluid through the first pressure chamber; iii) first actuation means adapted to move the first valve means to an open position, when the fluid pressure within the first chamber is below the first predetermined pressure level and which allows the movement of the first valve means towards a closed position, when the fluid pressure is above the first predetermined level, the first activation means comprises: a) a first diaphragm connected to the first valve means; b) a spring means adapted to act together with the first diaphragm, to deflect the first valve means away from a closed position, when the fluid pressure within the first chamber is below the first predetermined pressure level; c) means for retaining the spring means in deviation relation with the first diaphragm;
2. i) means adapted to prevent the flow of fluid through the second chamber at a pressure above a second predetermined level, comprising: i) a second valve seat means provided in the base; ii) second valve means adapted to engage with the second valve seat means, when the second valve means is in a closed position, thereby preventing the flow of fluid through the second pressure chamber; iii) the second activation means adapted to move the second valve means towards an open position, when the fluid pressure inside the second chamber is below the second predetermined pressure level and which allows the movement of the second valve means towards a closed position, when the fluid pressure is above the first predetermined level, the second activation means comprises: a) a second diaphragm connected to the second valve means; b) a spring means adapted to act together with the second diaphragm to deflect the second valve means away from a closed position, when the fluid pressure within the second chamber is below the second predetermined pressure level;
3. c) means for retaining the spring means in deviation relation with the second diaphragm. The two-stage pressure regulator assembly according to claim 1, further characterized in that it comprises: means for controlling the flow adapted to allow the flow of the high-pressure fluid through the regulator assembly, when it is in an open position and adapted to prevent high pressure fluid flow through the regulator assembly, when the flow control means are in a closed position; means adapted to dampen the deflection movement of the spring means, adapted to act together with the first diaphragm; and means adapted to dampen the deflection movement of the spring means adapted to act together with the second diaphragm. 3. The two-stage pressure regulator assembly according to claim 1 or claim 2, further characterized in that it comprises pressure release means communicating with the first pressure chamber and adapted to release the fluid at high pressure from the assembly, if the pressure of the fluid exiting the first pressure chamber exceeds a pre-selected value.
4. 4. The two-stage pressure regulator assembly according to claim 1 or claim 2, further characterized in that it comprises means adapted to filter impurities from the high-pressure fluid flowing into the first pressure chamber.
5. The two-stage pressure regulator assembly according to claim 1 or claim 2, further characterized in that it comprises a means for releasing the pressure communicates with the first pressure chamber and adapted to release the high-pressure fluid from the assembly , if the pressure of the fluid exiting the first pressure chamber exceeds a preselected value; and a means adapted to filter impurities from the high pressure fluid flowing to the first pressure chamber.
6. The two-stage pressure regulator according to claim 1 or claim 2, characterized in that it has means adapted to communicate the temperature that controls the fluid through the base.
7. The two-stage pressure regulator according to claim 1 or claim 2, characterized in that it has means for adjusting the setting of the second predetermined pressure level.
8. 8. The two-stage pressure regulator according to claim 3, characterized in that the first and second retaining means are adapted for the removable coupling with the base.
9. The two-stage pressure regulator according to claim 4, characterized in that the pressure release means, the filter means and the first and second valve means are adapted for removable coupling with the base.
10. The two-stage pressure regulator according to claim 5, characterized in that the first valve seat means defines a first hole and the second valve seat means defines a second hole having an equal or greater diameter in relation with the diameter of the first hole.
11. The two-stage pressure regulator according to claim 6, characterized in that the flow control means comprises a third chamber defined by the base, a first plug means activated by the solenoid adapted to operate between first and second positions. , the second plug means adapted to pneumatically communicate with the first plug means through a first channel and operate between the first and second positions, the second plug means being adapted to move to a first operating position by the first plug means moving to its first position, the second channel means defined by the first plug and adapted to communicate with the first pressure chamber, when the first plug is in the first position and avoid such communication in the second position, the first and second channel means have substantially different diameters.
12. The two-stage pressure regulator according to claim 7, further characterized in that it comprises a base having a first surface and a second surface, the temperature control means have inlet and outlet openings defined by the first surface and such openings in the inlet and outlet for temperature control and high pressure fluid inlet medium and regulated pressure fluid outlet means are defined by the first surface, and wherein the release means of pressure and the first and second activation means are placed substantially on a second surface.
13. The two-stage pressure regulator according to claim 8, characterized in that it comprises a fluid pressure sender removably attached to the base and communicating with the high-pressure fluid inlet means and located intermediate to the means of flow control and the first pressure chamber.
14. The two-stage pressure regulator according to claim 1, characterized in that the filter means communicates with the high-pressure fluid inlet means and is located intermediate to the high-pressure fluid inlet means and the flow control means.
15. 15. The two-stage regulator assembly according to claim 10, characterized in that the filter means comprises a filter housing adapted to be removably secured to the base of the regulator, the housing defining a substantially cylindrical filter chamber, a removable cylindrical, substantially hollow cross-section filter element having a closed first end and a second open end and defining a cylindrical surface area, the filter element is adapted for placement within the cylindrical filter chamber to substantially expose the entire cylindrical surface area to the high pressure fluid.
16. 16. The two-stage regulator assembly according to claim 11, characterized in that it has a cylindrical filter element made of sintered metal containing stainless steel, bronze or brass.
17. 17. The two-stage regulator assembly according to claim 1, characterized in that the means adapted to dampen the deflecting movement of the third and fourth spring elements comprise means for balancing the pressure, the balancing means comprising a floating member adapted for coupling substantially in seal form with the second valve means and therefore defining a fluid pressure reservoir, the second valve means defining a channel communicating between the reservoir and the second chamber.
18. 18. The two-stage regulator assembly according to claim 13, characterized in that the float member is connected to the base.
19. The two-stage regulator assembly according to claim 14, wherein the second valve means is further characterized in that it comprises a sealing means and the flotation member is adapted to engage with the sealing means.
20. 20. The two-stage pressure regulator assembly according to claim 1 or claim 2, further characterized in that it comprises a solenoid assembly comprising: a base adapted to define a housing for supporting a solenoid and having input means and fluid outlet, the base further defines a first chamber and a second chamber, the second chamber is in pneumatic communication with the first chamber by means of a first channel, the housing further defines a second channel that communicates fluid between the first chamber and the first chamber. output means, the first and second channels are of different diameters, pilot plug means adapted to operate between an open position and a closed position within the first chamber, the pilot plug means are adapted to move to the open position by the activation of the solenoid and thus allow fluid communication between the input and output means, With a second stopper means adapted to operate within the second chamber, between an open and closed position, the second stopper is adapted to move to the open position by the first stopper moving to an open position, the second stopper means that is adapted to increase fluid communication between the inlet and outlet means by movement to an open position.
21. 21. The solenoid assembly according to claim 20, characterized in that it has means for diverting the second plug means towards its closed position and the first channel is adapted, when the pilot plug means is in its open position, to communicate fluid under pressure from the first chamber to the second chamber to move the second plug means to its open position.
22. 22. The solenoid assembly according to claim 20, characterized in that it has means for reducing the pressure drop through the solenoid assembly by increasing the flow velocity of the fluid through the outlet means.

    SUMMARY The present invention provides a two-stage pressure regulator, improved for various compressed gases and more particularly pressure regulators used for gaseous fuels such as compressed or liquefied natural gas. The pressure regulator of the present invention is a heavy-duty, compact, high-flow, low-chill, low-pressure, low-slow-motion regulator that is suitable for both OEMs and for future use in the market. It can be used by itself, or with an optional third stage to provide a three-stage regulator such as the atmospheric types (or zero pressure differences) commonly used to regulate the fuel pressure for gaseous carburetion systems. It is particularly in mono-, bi-and dual fuel engine applications. The two-stage regulator of the present invention consists of an individual base ("the base of the regulator") on which all the components of the regulator are mounted., including the spring towers of the first and second stage regulator, a pressure release valve (or PRV), a spring tower, a filter assembly, a high pressure solenoid activated valve and a pressure sender. optional cylinder. The channels provided in the base, for example by machining, allow the flow of coolant or other fluid through the base to control the temperature of the pressure regulator and thus the outlet temperature of the gas flowing therethrough.