Classifications

• • G—PHYSICS
  • G05—CONTROLLING; REGULATING
  • G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
  • G05D16/00—Control of fluid pressure
  • G05D16/04—Control of fluid pressure without auxiliary power
  • G05D16/06—Control of fluid pressure without auxiliary power the sensing element being a flexible membrane, yielding to pressure, e.g. diaphragm, bellows, capsule
  • G05D16/0616—Control of fluid pressure without auxiliary power the sensing element being a flexible membrane, yielding to pressure, e.g. diaphragm, bellows, capsule the sensing element being a bellow
  • G05D16/0619—Control of fluid pressure without auxiliary power the sensing element being a flexible membrane, yielding to pressure, e.g. diaphragm, bellows, capsule the sensing element being a bellow acting directly on the obturator
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
  • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
  • F17C2205/00—Vessel construction, in particular mounting arrangements, attachments or identifications means
  • F17C2205/03—Fluid connections, filters, valves, closure means or other attachments
  • F17C2205/0302—Fittings, valves, filters, or components in connection with the gas storage device
  • F17C2205/0338—Pressure regulators
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
  • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
  • F17C2205/00—Vessel construction, in particular mounting arrangements, attachments or identifications means
  • F17C2205/03—Fluid connections, filters, valves, closure means or other attachments
  • F17C2205/0388—Arrangement of valves, regulators, filters
  • F17C2205/0391—Arrangement of valves, regulators, filters inside the pressure vessel

Definitions

• a pressure regulator includes a pressure-responsive bellows that is disposed to operate a valve seal in controlled manner in response to fluid pressure acting upon the bellows at a location downstream of the valve seal.
• pressure regulation according to the present invention establishes an inverse relationship between gas volume remaining in the cylinder and the regulated outlet pressure so that only low-pressure metering is required to obtain indication of the volume of gas remaining in a supply cylinder. This obviates the need for high-pressure metering, with associated hazards of rupture and leak at a location upstream of the pressure regulator, and permits direct coupling of the regulator to the shut-off valve of the cylinder to minimize the potentially hazardous portions of the system that operate at high pressures.
• FIG. 1 is a cross-sectional view of one embodiment of a generally cylindrically-shaped regulator according to the present invention illustrated operating under an extreme condition of high outlet pressure;
• Figure 2 is a cross-sectional view of the embodiment illustrated in Figure 1 operating under the extreme condition of low outlet pressure
• Figure 3 is a cross-sectional view of the illustrated embodiment of Figure 1 showing a modification to the bellows for controlling the regulation pressure;
• Figure 4 is a cross-sectional view of another embodiment of the pressure regulator of the present invention which is generally cylindrically-shaped in coaxial configuration and which is illustrated operating in an extreme condition of low outlet pressure;
• Figure 5 is a cross-sectional view of the embodiment of Figure 4 illustrated operating in an extreme condition of high outlet pressure
• Figure 6 is a pictorial diagram of a gas-pressure system assembled according to the present invention.
• FIG. 7 is a graph showing the inverse deviation of regulated outlet pressure as a function of inlet pressure which facilitates low-pressure monitoring of remaining gas volume in a supply cylinder.
• the regulator body 9 is generally cylindrical with inlet port 11 and outlet port 13 sealed to the body, for example, by electron-beam welding techniques to assure integral, leak-free attachment to the body 9.
• Conventional high-pressure fittings may be provided on inlet and outlet ports 11, 13 for convenient attachment to other fluid connectors of the system.
• the body 9 includes a seal seat 15 around aperture 17 that connects the inlet chamber 19 associated with inlet port 11 to the outlet chamber 21 associated with the outlet port 13.
• a generally cylindrical piston 23 is slidably disposed within the inlet chamber 19 to move in a direction into and away from sealing engagement with the seal seat 15.
• An elastomeric seal 25 may be attached to the piston 23, for example, by casting or cold-rolling a flange inwardly over the seal, to assure fluid-tight sealing engagement with the seal seat 15.
• the seal 25 may be formed of perfluoroelastomer (available as Kalrez from DuPont Co.), or other suitable chemically-inert elastomer.
• the piston 23 also carries a central rod 27 which protudes through the aperture 17 into the outlet chamber, and also carries a permanent magnet 29 encapsulated within the body of the piston 23.
• the inlet chamber 19 is sealed with an end cap 31 that also encapsules a permanent magnet 33 therein in magnetic-repulsion orientation with respect to magnet 29.
• the seal between body 9 and end cap 31 may also be formed by beam-welding techniques, or the like (after the parts are assembled within the inlet chamber 19) to eliminate the possibilities of gas leaks into the environment.
• the magnets 29 and 33 oriented to repel, the piston 23 and seal 25 are urged into normally--closed, sealing engagement with seal seat 15, and the rod 27 protrudes through the aperture into the outlet chamber 21.
• This sealing engagement is enhanced by pressure of the fluid at inlet port 11 acting on an area of the piston approximately equal to the area of aperture 17.
• the piston 23 and seal 25 may be urged into sealing engagement with surface 15 by a spring instead of the repelling magnets 29 and 33.
• a pressure-responsive controller 35 comprising a generally cylindrical bellows 37 sealed to end caps 39 and 41 to form an expandable pressure vessel.
• the end cap 41 is disposed to contact the rod 27 which protrudes through the aperture 17, and the end cap 39 is sealed to the body 9, for example, by electron-beam welding techniques, or the like.
• the parts of the regulator which are to be sealed against pressure leaks may all be formed of such bondable materials as aluminum, stainless steel, plastics, and the like, which also do not significantly effect the magnetic flux of magnets 29 and 33.
• the end caps 39 and 41 are internally dimensioned to prevent over-compression of the bellows at the limit of surfaces 43 and 45 coming into contact.
• the end cap 39 includes an elastomeric ball 47 disposed within an inner recess of channel 49 to serve as a temporary check valve until the ball 51 in the outer recess 53 is welded and sealed in place.
• the bellows assembly is formed and then pressurized to a selected pressure above ambient and sealed by welding ball 51 into recess 53. This internal pressurization causes the bellows 37 to expand longitudinally against its own resilient restoring force and thereby position the end cap 41 relative to the end cap 39 at a location that is representative of the net pressure differential acting upon the area of end cap 41.
• the sealing engagement of the seal 25 against the seal seat 15 is controlled by the degree of expansion of the bellows 37 in response to the fluid pressure in outlet chamber 21 that acts upon the bellows 37. Therefore, in an extreme condition of high outlet pressure, the bellows is compressed to the limit of surfaces 43 and 45 coming together, and the central rod 27 is disengaged from the end cap 41, as shown in Figure 1. The pressure-enhanced and magnetically-enhanced sealing engagement between seal 25 and seal seat 15 is preserved, and no fluid flows through the regulator.
• FIG. 2 there is shown a cross-sectional view of the regulator of Figure 1 operating in another extreme condition of substantially no fluid pressure in outlet chamber 21.
• the bellows 37 extends maximally until end cap 41 contacts the support 48 for the seal seat 15 and pushes the rod 27 and the attached piston 23 and seal 25 away from seal seat 15. Fluid under pressure is therefore free to flow from inlet port 11 through aperture 17 to the outlet port 13.
• the repulsion force by magnets 29 and 33 is overcome by the pressure force supplied by the bellows assembly, and the valve seal 15, 23 remains open for fluid flow therethrough until the pressure increases in outlet chamber 21.
• the bellows compresses proportionately and, via rod 27, the piston 23 and seal 25 approaches the seal seat 15 under the static magnetic force provided by magnets 29 and 33.
• the spacing between seal 25 and seat 15 decreases (due to increased pressure in outlet chamber 21)
• the flow of fluid therethrough decreases, thus decreasing the pressure in outlet chamber 21.
• Decreased pressure in outlet chamber 21 causes the bellows to expand and, via rod 27, increase the spacing between seal 25 and seat 15 to permit greater flow of fluid therethrough to increase the fluid pressure in chamber 21.
• the bellows assembly expands to a seal and seat spacing which establishes a fluid pressure in outlet chamber 21 that approximately equals the internal pressure in bellows 37.
• the initial pressurization of the bellows 37 establishes the fixed limit of outlet fluid pressure around which the present invention regulates.
• the regulator of Figure 1 is modified to include a fluid pressure connector 55 to the interior of the bellows assembly so that the regulating pressure limit of the assembly can be controlled in response to the pressure supplied to the interior of bellows 37.
• the operating conditions of the regulator can be tailored to provide slight increase around the regulating value of outlet pressure in inverse proportion to the inlet or supply pressure, as illustrated in the graph of Figure 7. As shown in the diagram of Figure 6, this characteristic is desirable for monitoring the volume of gas remaining in a cylinder 81 of the gas under high pressure, simply by metering 83 the outlet pressure at much lower pressure levels.
• the internal gas volume of the bellows assembly in the regulators 82 of the present invention is maintained low by incorporating the solid volumes of end caps 39 and 41 within the inner volume of the bellows to effectively "stiffen" the resilience of the bellows to changing pressure conditions.
• the diameter of the end cap 41 and, hence, the effective surface area of the bellows affects the amount of deviation about a stable value (in the form of droop or sag) in the curve of output gas pressure as a function of flow rate.
• the amount of such deviation decreases as the effective area of the bellows increases.
• the cross-sectional area of the aperture 17 is selected to establish a small inverse variation 85 in the regulated value of outlet pressure 87 for variations in inlet pressure due, for example, to declining volume of gas in a supply cylinder 81. For a given pressure, increasing the aperture size increases the force required to overcome the pressure against the seal.
• the bellows applies a constant force against a varying opening force, yielding the desired inverse deviation in outlet pressure.
• a slight inverse variation 85 in outlet pressure of, say, 20 pounds per square inch gage pressure may appear in the nominal regulated value of outlet pressure as the supply pressure from a high-pressure gas cylinder 81 varies widely as it is emptied with use.
• Such slight variations 85 in outlet pressure over the wide range 91 of inlet pressures permit convenient low-pressure metering 83 to provide indication of the supply pressure and, hence, of remaining volume of gas in the supply cylinder 81.
• a secondary regulator 89 may be included in the system at a location downstream of the meter and ahead of a utilization system to reduce the variations 85 in the pressure of fluid supplied to the utilization system.
• annular shield 70 and central anvil 72 which are concentrically disposed over the aperture 17, with the anvil 72 in contact with the central rod 27 to actuate the piston 23 and seal 25 through the aperture.
• the shield 70 includes a plural number of openings or vent holes 74 therethrough at spaced locations around the perimeter. This assembly in the structure of the present invention interrupts the lateral flow of fluid from aperture 17 and thereby reduces the Bernoulli effect upon the end cap 41. This assures smoother regulator operation by minimizing the conditions which tend to set up oscillations in the position of the end cap 41.
• FIG. 4 there is shown a cross- sectional view of a pressure regulator that is oriented in coaxial configuration with its associated inlet and outlet connections.
• the body 61 of the regulator is generally cylindrical from the inlet port 63 to the outlet port 65, and encloses generally cylindrical inlet channel 67 and outlet channel 69 that are connected via central aperture 71.
• Standard high-pressure connectors may be welded to the body 61 at inlet and outlet ports to prevent leaks.
• a piston carrying a seal for engaging the aperture are disposed within the inlet channel 69, with a rod carried by the piston protruding through the aperture 71 into the outlet channel 69.
• the piston and seal are urged into engagement with the sealing surface that surrounds aperture 71 by the spring 75 which bears against the filter element 77 which, in turn, bears against, and seals against. a mating surface in a standard high-pressure cylinder valve.
• the filter element 77 is a generally cylindrical bellow shell of suitable sintered metal or ceramic material which is open at the input end and closed at the inner end. This filter 77 is arranged within the inlet port 63 to filter the fluid received from a supply. The filter 77 may thus be conveniently replaced each time a new supply cylinder is re-connected to the inlet port 63.
• the outlet channel 69 includes a bellows assembly 73 which is pre-charged to a level of fluid pressure about which the regulator is to operate, as previously described.
• the aperture 71 is open for fluid flow therethrough with the bellows assembly 73 expanded during conditions of low pressure within outlet channel 69. And, as shown in Figure 5, the aperture 71 is closed against fluid flow in response to the bellows assembly 73 being compressed under condition of high pressure within outlet channel 69.
• this illustrated embodiment of the regulator of the present invention operates as previously described in connection with the embodiment illustrated in Figures 1 and 2 to adjust the aperture opening in response to the fluid pressure in outlet channel 69. In this way, the outlet pressure is maintained at substantially the same pressure as is sealed within the bellows assembly 73, substantially independently of variations in supply pressure.

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• Physics & Mathematics (AREA)
• Fluid Mechanics (AREA)
• General Physics & Mathematics (AREA)
• Engineering & Computer Science (AREA)
• Automation & Control Theory (AREA)
• Control Of Fluid Pressure (AREA)
• Earth Drilling (AREA)
• Valves And Accessory Devices For Braking Systems (AREA)
• Pressure Vessels And Lids Thereof (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=25245493

Family Applications (1)

Country Status (13)

Families Citing this family (7)

Citations (2)

Family Cites Families (18)

• 1987
  • 1987-02-04 IE IE870293A patent/IE870293L/xx unknown
  • 1987-02-04 ZA ZA87799A patent/ZA87799B/xx unknown
  • 1987-02-04 CN CN198787102162A patent/CN87102162A/zh active Pending
  • 1987-02-04 GB GB8723263A patent/GB2193559B/en not_active Expired - Lifetime
  • 1987-02-04 JP JP62501322A patent/JPS63502699A/ja active Pending
  • 1987-02-04 AU AU70343/87A patent/AU7034387A/en not_active Abandoned
  • 1987-02-04 IT IT8719258A patent/IT1216874B/it active
  • 1987-02-04 MX MX005165A patent/MX171410B/es unknown
  • 1987-02-04 EP EP19870901808 patent/EP0256114A4/de not_active Withdrawn
  • 1987-02-04 WO PCT/US1987/000215 patent/WO1987004765A1/en not_active Application Discontinuation
  • 1987-09-30 NO NO874114A patent/NO874114D0/no unknown
  • 1987-10-02 FI FI874325A patent/FI874325A/fi not_active Application Discontinuation
  • 1987-10-02 DK DK517687A patent/DK517687D0/da not_active Application Discontinuation

Patent Citations (2)

Non-Patent Citations (1)

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