US3044488A - Pressure-regulators for fluids - Google Patents

Description

y 1962 R. M. 'MENNESSON 3,044,488

PRESSURE-REGULATORS FOR FLUIDS Filed Oct. 19, 1959 2 Sheets-Sheet 1 Q0651) Maufl'f-i EAN-Errol WWI ATTORNEKS July 17, 1962 R. M. MENNESSON PRESSURE-REGULATORS FOR FLUIDS 2 Sheets-Sheet 2 Filed Oct. 19, 1959 mm NW E v NVE N TOR RM-HT (Wear/cs fl/wm ATTORNEY) nited 3,044,488 PRESSURE-REGULATORS FOR FLUIDS Robert Maurice Mennesson, Neniliysur-Seine, France, assignor to Societe dApplications et de Constructions pour Materiel Automobile (S.A.C.M.A.), Neuilly-sur- Seine, France, a corporation of France Filed Get. 19, 1959, Ser. No. 847,285 Claims priority, application France Nov. 3, 1958 9 Claims. (Cl. 137514) The present invention relates to pressure-regulators for fluids, that is to say to devices which are designed to deliver a fluid at a practically constant pressure (higher or lower than atmospheric pressure) irrespective of the variations, within certain limits, of the rate of flow of the device and of its supply pressure; and among these devices, the present invention concerns more especially-- since in this case its application appears to be of the greatest valuealthough not exclusively, those devices which are intended to be incorporated in installations of pneumatic metrology which are intended to be supplied with air at constant pressure.

The object of the present invention, above all, is to adapt the said devices so that they meet the various conditions required in practice more effectively than has hitherto been possible, particularly by reason of their simplicity and their reliability of operation.

The invention mainly consists both in constituting the devices of the type in question by a receptacle which communicates through a narrow orifice with a chamber in which there exists a pressure which differs from the atmospheric pressure to a greater extent than does the constant pressure P to be established (but in the same direction as this latter), while a valve tends to maintain in the closed position a passage leading from the said receptacle towards the atmosphere, the said valve tending to be opened by the pressure existing in the receptacle; while at the same time the said valve is supported with respect to the said receptacle and without causing friction, by means of at least one deformable diaphragm which preferably delimits a variable-volume chamber communicating with the receptacle through an orifice having a small section so that the said chamber has a dash-pot eitect on the valve.

Apart from this principal arrangement, the invention consists in certain other arrangements which are preferably employed at the same time and which will be explained in greater detail below.

The. invention contemplates more especially a certain method of application (the method by which the invention is applied to pressure regulators for pneumatic metrology), as well as certain methods of construction of the above-mentioned arrangements; and the invention is still more especially directed, by way of new industrial products, to devices of the type in question comprising the application of these same arrangements, the special parts and tools intended for their construction, as well as the fixed or movable installations comprising devices of this type.

The present inventionwill in any case be clearly understood by means of the additional description which follows below as well as the accompanying drawings, both the additional description and drawings being understood to be given particularly by way of indication and not in any sense by way of implied limitation.

FIG. 1 of these drawings shows diagrammatically in vertical cross-section a pressure regulator for compressed air constructed in accordance with the invention.

FIG. 2 shows, similarly to FIG. 1, a depression regulator'also constructed in accordance with-the present invention.

Finally, FIGS. 3 and 4 relate to alternative forms of construction of the two above-mentioned regulators.

In accordance with the present invention and more especially in accordance with one particular method of application as well as in accordance with those methods of construction of its various parts to which it would appear necessary to give preference, with the intention, for example, of first constructing a pressure regulator so as to supply air to a pneumatic metrology installation at a pre-determined constant pressure P which is higher than atmospheric pressure, the method of operation is carried out as follows or in like manner.

This device is essentially constituted as shown by FIG. 1, by a Vertical body 1 closed by means of two end portions 2 and 3 in such manner as to constitute a chamber 4 duit 8 which conveys air at constant pressure to an outlet orifice 9 (which can in turn open into any ambient atmosphere at a pressure which is lower than or equal to the pre-determined constant pressure mentioned above).

A passage 10 leading to the atmosphere is formed in the upper wall of the upper end portion 2 of the chamber 4, the said passage having the shape of a fiat, hori- Zontal and circular seating with a sharp ridge, for a valve 11 which is also fiat and has a slightly larger diameter than its seating, this valve being guided in such manner that it is capable of moving vertically without friction.

Thus, under the opposing effects of the pressures applied to the two faces of the said valve 11, when the pressure existing in the chamber 4 has reached a certain value, the said valve 11 tends to rise against the eiiect of gravity and to assume a position of equilibrium, thus ensuring the regulation of the pressure existing in the chamber 4.

It is an advantage to fix the valve 11 to the upper extremity of a rod 12 which is supported and centered in the interior of the chamber 4 by means of two annular diaphragms 13 and 14, at the centres of which is fixed the rod 12 and the edges of which are gripped between the body 1 and the end portions 2 and 3 of the chamber 4.

The upper diaphragm 13 should preferably be pierced with at least one opening 15 enabling the air to fiowwith practically no loss of pressure from one side to the other of the said diaphragm and thus to pass from the chamber 4 towards the outlet passage 10.

The lower diaphragm 14 should then be arranged in such manner that it forms a space in the lower end 3 of the receptacle 4, for a small variable volume compartment 16 which communicates only with the said chamber by means of an orifice 17 having a section of such small size that the said compartment has a dash-pot effect on the valve 11, through the intermediary of the rod 12, this orifice 17 being preferably pierced through the base itself of the rod 12 as shown in FIG. 1.

Finally, the said rod 12 is preferably caused to carry, slightly above the diaphragmv 14, a deflector 18 adapted to direct the condensations, as well as the oil and the small foreign bodies entering through inlet orifice 5, towards a groove 19 formed close to the base of the body 1 and communicating with the exterior by means of an evacuation orifice 20 having a small section.

The diaphragms 13 and 14 will preferably be of a coated fabric for example, or of a natural or synthetic jected to the same pressure.

rubber, so as to have great flexibility within the limits of deformation which are imposed upon them by the opof this pressure which acts on the said valve, on a section equal to the section-of the seating whilst the remainder of the valve and its other face are subjected to atmospheric pressure. The valve 11 is thus urged, in the direction of its opening by a force which exactly balances the action of gravity on the valve and the members which are rigidly fixed to this latter.

Part of theair at a pressure P existing in the receptacle 4 passes out through the orifice and carries away the condensations; another part of this air serves to supply the orifice 9 and the excess portion passes out between v the seating 10 and the valve 11.

The variations, either in the supply pressure or in the rate of flow of the orifice 9 (the rate of flow can vary either by variation of the section of the said orifice, or by variation of the pressure ofthe chamber into which it flows), simply result in a more or less substantial lift of the valve Hi It is understood that, by virtue of the orifice 17, the two faces of the lower diaphragm 14 are normally sub- But in the case of abrupt variations either of the supply pressure or of the section of the orifice 9, owing to the displacement of the valve and consequently owing to'the variation in volume of the chamber 16, the two faces of the diaphragm 14 are subjected .for a very short period of time to different pressures which become once. more equal only when a suflicient quantity of air has been able to pass through I vibrations is prevented.

The depression regulating device which forms the in the rate of flow through orifice 9 (this rate of flow can vary either by variation of the section of said orifice, or by variation of the pressure in the space on the outside of chamber 4), simply result in a more or less substantial lift of valve 11.

his understood that, by virtue of the orifice 17, the two faces of the upper diaphragm 14are normally subjected to the same pressure. But in the case of an abrupt variation of the pressure under diaphragm 14, due to the displacement of the valve and consequently to the v-aria tion in volume of chamber 16, the two faces of the diaphragm 14 are subjected for a very short period of time to different pressures which are re-established only when a suflicient quantity of air has been able to pass through the orifice 17. But as this latter is relatively small, the passage of air is relatively slow and thus the inception of vibrations is prevented.

If it is desired. to regulate the practically-constant pressure P to be maintained in the chamber 4, it is an advantage to provide an orifice for communication with free air and having an adjustable section, between the atmosphere and the variable-volume compartment 16 and for this reason, for example, the said compartment is caused to comprise, as shown in FIG. 3, a passage permitting of communication with free air and having an adjustable section, by piercing the wall of the bottom portion 3 with an orifice 21 adapted to be more or less shut off by means of a needle-valve 22 mounted at the extremity of an adjustable screw. 23, while the air flows between the orifice 21 and the needle-valve 22 and passes out into the atmosphere through an orifice 24.

It will be understood that if the needle-valve 22 com- 7 pletely closes the orifice 21, this reverts to the case of l the orifice 17. But as this latter is relatively smal1,the

subject of FIG. 2 comprises the same elements as the 7 device shown in FIG. 1,'these being designated by the same referencenumbers, the only diiferences being that: Source 7 is a vacuum source, i.e. the pressure therein is lower than atmospheric pressure; 7

The seating 10 is located in the lowerencl portion 2 of the chamber 4, the valve ll'being the-n located in the interior ot' the said chamber;

The diaphragm 13, pierced with the opening 15, is the lower diaphragm;

The diaphragm 14 forming the compartment 16 isthe upper diaphragm; and, I

The deflector 18, the groove 19 and the evacuation orifice 20 have been eliminated.

The operationof this depression regulator is analogous I to the operation of the pressure regulator of FIG. 1.

If it is assumed that, initially, the pressure in space 7 is the atmospheric pressure, the flat valve 11 rests. on the seating 10. I

If the pressure in space '1 isthen gradually reduced,

then, as soon as the suction in the chamber 4 has reached a certain value, the valve 11 will be lifted under the efiect of this suction whichacts on the upper face of said valve, on a section equal to the section of the seating 10 whilst the under face thereof is subjected to at mospheric pressure. The valve 11 is thus urged upward- V ly, in the direction of its opening by a force whiohexactly balances the action of gravity on the valve and the parts which are rigidly fixed thereto. 7 p

flows into chamber 4 through orifice 9 and also through the interval between the seating 11 and the valve V The variations, either in the pressure in space 7 or regulation which is thus carried out can be effected either by mere adjustment, since the required weight of the butt which is rigidly fixed to the valve is diificult to obtain accurately; or else by means of a true adjustment which serves to obtain a pres sure P which is different from the predetermined pressure provided, in accordance withthe main patent by the eflect of gravity alone on the unit which is rigidly fixed to the'valve.

The depression regulating device which forms the subject of FIG. 4 comprises the same elements as the device shown by FIG. 3 and designated by the same reference numbers, the only' difierences being that:

Source 7 is a vacuum source;

The seating '10 is located in the lower end portion 2 of the'chamber 4, the valve 11 being in this case located in the interior of the said chamber,

The diaphragm 13, which is pierced with the opening 15, is the lower diaphragm,

The diaphragm 14 which forms the compartment 16 is the upper diaphragm,

The operation of the depression regulator of FIG. 4

is entirely similar to the operation of the regulator of FIG. 2, the only difierence being that the action of dashpot chamber 16 can be adjusted by means of needlevalve 22.

What I claim is:

1. An apparatus for maintaining a' constant gaseous fluid'pressure different from atmospheric pressure in a chamber provided with two orifices, an inlet one and an outlet one, respectively, one of said orifices communicatmg with the outside of said chamber for transmitting said constant pressure thereto, which apparatus comprises, in combination, a space containing a gaseous fluid at a pressure such that said constant pressure to be maintained in said chamber is always intermediate between the pressure in said space and atmospheric pressure, conduit means of restricted cross section area for connecting said space with the other of said orifices, a passage leading from said chamber toward the atmosphere, valve means arranged to maintain said passage closed, said valve means tending to be opened by the diiference be tween the fluid pressure in said chamber and atmospheric pressure, at least one deformable diaphragm for supporting said valve means without friction with respect to said chamber and means for equalizing pressures on both sides of said diaphragm.

2. A pressure regulator device as claimed in claim 1, and further comprising: an auxiliary chamber of variable volume delimited by said diaphragm and one end portion of said main chamber; said means for equalizing pressures on both sides of said diaphragm consisting of an orifice forming a communication between said main and auxiliary chambers, said last mentioned orifice being of small cross section area whereby said auxiliary chamber provides a dash-pot effect on said valve.

3. A pressure regulator as claimed in claim 2, in which said auxiliary chamber of variable volume communicates with said main chamber only.

4. A pressure regulator as claimed in claim 2, in which said auxiliary chamber of variable volume also communicates with the atmosphere through a further orifice of variable section.

5. An apparatus for maintaining a constant gaseous fluid pressure ditferent from atmospheric pressure in a chamber provided with two orifices, an inlet one and an outlet one, respectively, one of said orifices communicating with the outside of said chamber for transmitting said constant pressure thereto, which apparatus comprises, in combination, a space containing a gaseous fluid at a pressure such that said constant pressure to be maintained in said chamber is always intermediate between the pressure in said space and atmospheric pressure, conduit means of restricted cross section area for connecting said space with the other of said orifices, a vertical passage leading from said chamber toward the atmosphere, said vertical passage having a top horizontal edge, a vertical rod extending in said chamber along the axis of said passage, valve means carried by said rod extending over said passage top edge, said valve means tending to be opened by the difference between the fluid pressure in said chamber and atmospheric pressure, two annular diaphragms, an upper one and a lower one, spaced apart from each other and fixed in said main chamber to support and center said rod, at least one opening pierced in the diaphragm .nearest to said passage thereby permitting fluid to pass through said diaphragm without substantial loss of pressure and means for equalizing pressures on both sides of the other of said diaphragms.

6 A pressure regulator device as claimed in claim 5, in which the diaphragm furthest from said passage forms an auxiliary chamber of variable volume with the corresponding end portion of said main chamber, said means for equalizing pressures on both sides of said last mentioned diaphragm consisting of an orifice forming a communication between said main and auxiliary said last mentioned orifice being of small cross section area whereby said auxiliary chamber provides a dash-pot effect on said valve chambers.

7. A pressure regulator device as claimed in claim 6, intended to regulate the fluid pressure in said main chamber to a constant value greater than atmospheric pressure, in which said passage is located at the, upper part of said main chamber, said auxiliary chamber acting as a dash-pot at the lower extremity of said main chamber.

8. A pressure regulator device as claimed in claim 6,

intended to regulate the fluid pressure in said main chamber to a constant value lower than atmospheric pressure in which said passage is located at the lower extremity of said main chamber, said auxiliary chamber acting as a dash-pot at the upper extremity of said main chamber.

9. A pressure regulator device as claimed in claim 6, and further comprising: a deflector member fixed on said rod slightly above the diaphragm furthest from said passage, so as to direct condensation, oil and small foreign bodies present in said main chamber towards the periphcry of said chamber; a channel formed adjacent the periphery of the lower end of said main chamber to receive the substances from said deflector; and an evacuation orifice of small section between the bottom of said channel and the exterior of said chamber.

References Cited in the file of this patent UNITED STATES PATENTS 1,204,520 Tuttle Nov. 14, 1916 1,291,609 Nichols Jan. 14, 1919 1,302,538 Gulick May 6, 1919 1,631,142 Masters June 7, 1927 1,751,046 Martin Mar. 18, 1930 FOREIGN PATENTS 302,306 Italy Oct. 24, 1932

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