CA1250207A - Flowgrid regulator - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
A flowgrid regulator for use as a flow control device in conjunction with a pilot system. The invention includes a valve body, containing a flow barrier, that connects to a spring casing with a throttling plate, spacer and diaphram sandwiched therebetween. The throttling plate intersects the barrier and includes openings on either side of the barrier intersection for passing a flow under pressure therethrough.
The diaphram is constructed of a non stretchable flexible material and is maintained to move vertically above the throttling plate to position a throttling element bonded thereto into covering engagement with the throttling plate openings. The diaphram position is controlled by a combination of spring force and pressure differential as supplied by the pilot system connection thereto to urge the throttling element against the throttling plate openings thereby controlling flow area and now rate.

Description

BACKGROUND OF TI~E INVENTION
Field of the Invention:
This invention relates generally to diaphram valves for controlling fiow of various fluids.
05 Prior Art:
Previous desi~ns of control devices operated by a pressure differential have genera21y involved mechanisms that include n rubber or elastomeric diaphram that is stretched to open, relying, at least in part, on the tensile strength of the elastomer in conjunction with a pressure differential to return the valve to the closed position.
l0 Examples of several of these types of valves are shown in patents by: Rich, U.S.
Patent No. 2,37q,791; Bryant, V.S. Patent No. 2,353,143; and Davis, U.S. Patent No. 2,677,390. Such reliance on elastomer tensile strength has certain inherent design deficiencies that the present invention, by utilizing a flexing diaphram with fabric reinforcement to provide high tensile strength rather than a stretching, purely 15 elastomer diaphram, improves upon. These deficiencies are: (1) diaphram travel or degree of opening is limited by the tensile strength of the elastomer material; (2) diaphram tensile strength and stretching characteristics are adversly affected by temperature from ambient and fluid expansion that are assoicated with pressure reduction; (3) diaphram travel (valve opening) must be limited to avoid instability, 20 fluttering, or chattering, resulting in a need for large throttling area to achieve acceptable capacity; (4) the diaphram must be fairly thick to provide durability and strength for a throttling operation and to avoid wear failure due to the presence ot abrasive materials in the fluid stream, which durability requirements results in the need for greater minimum pressure differential to open such diaphram valve; (5) the 25 tendency of the elastomer material to "take a set", failing to return to its original shape, increases with elastomer thickness resulting in a sluggish operation at lower temperatures. In summary, it is difficult to design an elastomer diaphram that will meet the conflicting requirements of durability, stretchability, stability, and acceptable minimum pressure differential for opening.
Where flow control devices have not utilized a stretchable diaphram element such have taught other closure arrangements. For example, patents by:
Randall, et al., U.S. Patent No. 3,020,925; Spence, U.S. Patent No. 2,860,657; Zadoo, V.S. Patent No. 3,792,ql3; and Johnson, et al., U.S. Patent No. 3,064,675, show valves that involve an ori~ice and valve plug arrangement connected to a diaphram and are closed, generally, by a spring arrangement.
Unlike earlier devices, the present invention is directed towards Q
regulator that utili~es a molded fabric reinforced elastomeric diaphrarn with high 05 tensile strength that is flexible but does not stretch, and so does not suffer from the inherent problems of such stretchable diaphrams, but is functionally similar thereto.
SUMMARY O~ THE INVENTION
It is a primary objective of this invention to provide a nexible diaphram - valve that includes a flexing diaphram bonded to a flexible throttling element as A
flow control device that is capable of providing consistant operation at high and low pressure differentials, varying temperatures, and is not dependent on the tensile strength of the base elastomer used.
It is another object to provide a flexing diaphram valve for controlling flow that is constructed from a molded fabric rein-rorced elastomeric material to provide a diaphram with very high tensile strength that is flexible but will not stretch.
It is another object to provide a flow control device where a minimum pressure differential required for operation is controlled by a selection of a spring biasing for acting upon the flexing diaphram.
It is another object to provide a flow control device that can be used to manipulate flow to control pressure (upstream or downstream), temperature, level, or the like by selection of an appropriate pilot system.
It is another object to provide a diaphram operated îlow control device with a main throttling element constructed to resist "taking a set" and will respond quickly to a pressure change input from a pilot system.
It is another object to provide a flowgrid regulator whose flow capacity and characteristics can be varied by a selection and installation of a flow area having a particular shape and area.
It is another object to provide a nexing diaphram operated flow control device that has few parts and can be manufactured at low cost.
It is another object to provide a flow control device that may be easily disassembled in the field for maintenance and cleaning without requiring removal of a valve body portion thereof from the pipeline.

~t~ Z07 It is another object to provide a regulQtor devlce that can incorporate multiple diaphram throttling elements on ~ single valve body to provide more capacity or to provide backup in case of a failure.
It is another object to provide a diaphram flow control device that can be 05 used with li~uids Qnd compressible gases.
It is another object to provide a flow control device that is bi-direct-onal in nOW.
~ t is another object to provide a diaphram flow control device that has wide rangeability from maximum to minimum flow and avoids fluttering, chattering, 10 surging, and instability.
It is another object to provide a flow control device that utilizes Q two stage pressure drop for guiet operation and to minimi~e liquid cavitation at high pressure drops.
In accordance with the above objects, the present invention is in a.flowgrid 15 regulator for use in conjunction with a pilot system. Thc flowgrid regulator includes a housing having a valve body portion for connection between inlet and outlet flow passages, the valve body including ~ barrier separating the flows. The housing is arranged to be broken to separQte a sprlng casing or loading chamber from the valve body above the barrier and provides for fixing in place a throttling plate whose 20 openings or passages ther~through are on either side of a solid area that seals against the barrier. The throttling plate is selected to provide a flow area of a desired shape and open area for a certain capacity or type of flow across that barrier. Above the throttling plate, suspended between a spring casing base and a spacer, to lie across that throttling plate, sepQrating the valve body from an open cavity, is Q diaphram.
25 The diaphrnm is preferably constructed from a fabric reinforced elastomer thst is flexible and is reinforced to have a high tensils strength and will not stretch. The diaphram has attached, preferably in the fabrication process a somewhat elastic throttling element, supported across, in covering attitude, to the throttling plate. The fabric rsinforced diaphram allows for vertical travel of the throttling element 30 whereby, in response to a pressure differential that is provided by a pilot system, taking into account a loaded spring action against diaphram vertical tr&vel, the throttling element will lift or "peel" off the throttling pl0.te, allowing a flow to pass through the throttling plats respons;ve to the pressure differentiaL

The preferred throttling element is formed during diaphram fabrication where the diaphrarm material is coated with R relatively soft elastomer that elastomer flowing into a mold of the throttling element that, when cured, is integral thereto, and may be reinforced with lateral rit~s implanted therein that extend parallel to one 05 another and across the direction of flow through the flowgrid regulator. The throttling element wiII lift off the throttling plate when a greater pressure exists on theundersurface thereof than is present in the spring casing in combination with the force exerted by a loaded spring arrangement, the throttling element tending to peel off from the throttling plate, the ribs, when present, reinforcing the elastomer to prevent 10 damage at high pressure differentisls.
The diaphram is spring loaded to clamp the throttling element into closing engagement over the throttling plate openings. The spring is preloaded nnd that load is distributed to exert the biasing force on the diaphram and throttling element, which force augments the force resulting from the pressure differential developed by the 15 pilot system connected thereto. The pilot system provides a prassure within that spring casing or loading chamber that is related to the flow re~uired.
Brief Description of the Drawings These and other objects will appear from the following detailed discription in which the preferred embodiments have been described in detail in conjunction with 20 the accompanying drawings.
Fig. 1 is a side elevation view of the flowgrid regulator of the present invention connected to a pilot system as it would be arranged to function RS a pressure reducing regulator;
Fig. 2 is a top plan view of the flowgrid regulator of Fig. 1 shown removed 25 from the system;
Fig. 3 is a side elevation sectional view taken along the line 3-3 of Fig. 2 showing the flosvgrid regulator interior, es including a valve body wherein is arranged a barrier separated from a spring casing by a juxtapositioned throttling plate anddiaphram member with a throttling element;
Fig. 4 is a top plan view of an embodiment of a throttling plate removed from the flowgrid regulator of Fig. 3;
Fig. 4A is a sectional view taken along the line 4A-4A of Fig. 4;
Fig. S is another embodiment of a throttling plate;
Fig. 6 is still another embodiment of a throttling plate;

R~

Fig. 7 is n to2 plan ~rie~ of thc throttling blement portion of the diaphrnm member remo~ed fro:n the flowgrid regulator of Pig. 3 showhlgt in brck!en lines, a number of spaced ~?art pnrelLel ribs implented in the throttling element;
Pig. 8 is an angle body ~,ersion of the lower housing portion shown brol~en 05 away from the sprlng casing of tJIe flowgrid regulntor;
Fig. 9 is another embodiment of the Ilowgrid regulator shown as including, s~ithln a spring casing, a loaded elliplical spring for provEding biasinLT to the diaphrarn member;
~ig. lG is a side elevation view of ~nother embcdiment of an elliptical 10 spring; and Fig. 11 is a side eLevation sectional view like that of Fig. 3 e):cept sho~ving an arrangement of duEI flo~grid regulators of the present invention that utilize a single v~lve body.
DETAILRD l)ESCRIPTION
E~eferring now to the drawings:
Fig. 1 shows ~ systematic view of a fLowgrid re~llator 20 of the present invention instaLled in line 21 whercthrough a fLuid under pressure, usually a gas is fLowing. ~'he Lowgrid regulator is interposed therein to control that fLow. In th;s arrangement the flowgrid regulator wilL func~ion as a pressure reducing vaLve, opening 20 to increase flow when the downstream pressure fnlls belo~-~ the set point of a pilot regulntor 24. The fLowgrid regulator may be operated singly, or as illustrated in the embodiment of ~ig. ll, can be a.rnnged to function with another like device providing A greater flow than i;, possible with one flowgrid regulator, or can be used as a back up with dudl or duplicats pilot cuntrol systems.
In Fig. 1 the ~owgrid re~llutor 20 i~ shown arranged in line ~1 that connects aLso through line 22 t.~ a pllot ~ystem 23. The pilot syst~m includes the piLot regulator 24 thnt is a simple self-operating pressule regulator, ~nd constitutes a variable orifice whose opening ~nd closing is gcverrled by the pressure available through line 26. In practice, a pllvt sold by ~isher Controls iderltified as type 67 hns 30 been found to operate satisfactorily as the pilot regulator in the pilot system. Such a pilot regulAtor 24 is adjustnble, as llLustrated by screw 2', for settlng a desired pressure, whereby the pilot regi'ator opening is conLrolled by ~ reduction in pressure below the set pressure throllgh v line 26 that connects the pilot to the downstream system through line 2l. Lim3 27 intersects thc UpstreaM line 21, and supplies pressure to the pilot regulAtor ~-i through a fixed orifioe 28, and at a T connector 29 that conne~ts lhrough line 22, to the flowgrid regulator.
The flowgrid regulator 20 of the present invention provides for opening in response to a pressure differential across the di&phram and thottling element labeled 05 as shown in Fig. 1, P2 and P3 respectively. For a pressure reducing control application with the described pilot system 23, that should be taken as typical, the flow ismanipulated eO maintain precise control of pressure in the outlet or downstream system P~. The pilot regulator 24, a simple salf operated pressure regulator, responds to change in the pressure P4 by ~arying the openi~ of a valYe therein, functioning as 10 ~ /ariable orifice. rhe pilot regulator, in con~wlction with fixed orieice 28, which is smaller than the variable orifice 24, forms a pneumatic or hydraulic fluid amplifier that is the pilot system 23 and is responsive to a process variable such as pressure, temperature, fluid level, and the like. The variable orifice can be constructed to respond to pressure changes as shown or to changes in flow, temperature, level, or 15 on/off signals to con trol the action of the flow~rid re~ulator in response to those vari~bles. Flowgrid regulator operaeion is controlled through the pilot system 23, connected as described, to provide a pressure P3 into a spring casing 30 that is located abo~/e a valve or throttling element 44 therein that opens in response to pressure differential (P2-P3).
In practice, as the pilot 24 opens responsive to a decrease in pressure P4 flow increases through the fixed orifice 28. As flow increases through tnat fixed orifice the resulting pressure drop is conducted through line 22 to sprin g casing chamber 35 and loading pressure P3 within the spring casing assumes some value between Pl and P4. Within the flowgrid regulator, as illustrated in ~ig. 3 an(l as will 25 be explained in detail later herein, an interstage pressllre P2 is present at a throttling plate 33, with the pressures P2 and P3 separated by a diaphram 43 that is preferably a molded fabric reinforced elastomeric material whereto is secured a throttling element 44 that is also preferably formed in the molding process from that elastomeric material and is therefore integral to the diaphram. A pressure differential P2 ~ P3 is 30 therefore present across the diaphram and will result in an upward force opposing a spring force exerted by a compressed coil spring 46 on diaphram 43 that i9 contalned in spring casing 30. Force P2 -P3 also opposes force P3 - P4 which acts to llold the throttling element 44 against the throttling plate 33. A force balance situationtherefor results which controls the position of the throttling element with respect to the throttling plate that in turn controls the amount of open area through the flowgrid regulator. With the flowgrid regulator open, flow travels from upstream to an interst~ge chamber 36 above the throttling pla$e to downstream. The resulting increase in flow into the downstream system will increase the pressure P4 in that 05 downstream ~system. As P4 increases the pilot regul~tor 24 will close resulting in a decrease in flow through the pilot system and fixed orifice 28. That decrease in flow res~ùts in an increase in loading pressure P3, and with the increase in P3, the pressure differential P2 ~ P3 is reduced, the force exerted by coil spring ~6 and the increase in pressure differential P3 - P4, then forces the throttling element 44 against the 10 throttling plate 33 reducing the flow area, and results in a reduction in flow through the devicæ lf the requirement for flow is reduced to ~ero then pilot regulator 24 closes Pressure will then squalize across fixed orifice 28 and loading pressure P3 will equal ir~et pressure Pl. When inlet pressure Pl equals loading pressure P3 the throttling element 44 will close completely against throttling plate 33, with the load 15 from coil spring 46 in combination with the pressure differential P3 - P4 forcing the throttling element aguinst the throttling plate resulting in tight shutoff.
The above functional description of a pilot system 23 and its interaction with the flowgrid regulator 20, of the present invention, has included a brief synopsis of the functioning of the major components of the flowgrid regulator. These 20 components are described in detail later herein with r espect to Fig. 3, and were provided to outline one functional arrangement of the present invention. It should be understood, however, that the flowgrid regulator can be used with other types of pilot systems functioning to selectively provide a fluid flow therethrough. The described pilot system is, of course, a basic pneumatic or hydraulic amplifier arrangement and 25 such systems preferably provide a built in flexibility in that the opening limits of the pilot regulator, that is the variable orifice, can be adjusted and even the fixed orifice can be varied by substituting one fixed orifice for another to achieve a desired functional relationship. In practice, the fixed orifice will be smaller in diameter than the variabls orifice to function as described. Such pilot or variable orifice can be 30 conskucted to respond to pressure changes, or to changes in flow, temperature, or on/off signals.
Fig. 2 shows a top plan view of the flowgrid regulator 20 of the present invention removed from line 21 and the pilot system 23 of ~ig. 1. Shown therein the spring casing 30 is flanged outwardly at its base 30a into a square shape the corners thereof having holes formed therethrough to receive bolts that secure it to a valve body 31 sandwiching, in stacked relationship as shown in sectional view of Fig. 3, throttling plate 33 and a spacer 32 therebetween. As shown in Fig. 2 and 3, the assembly is maintained together by turning of nuts 34a over ends of bolts in 34 that 05 fit, as shown in broken lines in Fig. 3, through the spring casing base 30a corners to axtend below a nange formed in the valve body outside of the coupling to line 21 such that the head 34b of each bolt is accessible from outside the flowgrid regulator.
The flowgrid regulator of Fig. 3, proceeding from top to bottom, includes the spring casing 30 that contains n chamber identified as loading chamber 35.
lO Pressure admitted from line 22 through inlet port 40, P3 acts therein upon diaphram 43. A pressure P2, the pressure present in an interstage chamber 36 located below the diaphram 43 and above the throttling plate 33 acts on the diaphram from the opposite direction. ~ pressure differential P2 -P3, is thereby provided across the diaphram.
The vaive body includes a barrier 37 that is curved upwardly from each side thereof so 15 to direct the flow from line 21, at a ninety degree upward angle to the flow line, the barrier terminating in an edge 38 that fits snuggly against, in sealing engagement with, a closed or solid center portion 39 of throttling plate 33. That, as shown in Fig. 4A
may be relieved to control the area of the sealing surface. So arranged, the pressure in the loading chamber 35 wiU be that pressure provided by the pilot system, loading 20 pressure P3, and the pressure in interstage chamber 36 will be identiied as pressure P2, with each pressure acting on opposite surfaces of the diaphram 43. Pressure P4 in the nowgrid regulator outlet also creates a force on diaphram 43.
Flowgrid regulator 20 functioning, as set out above, is provided by vertical or peeling movement of a diaphram 43 within cavity 41 above the throttling plate.
25 The height of CQVity 41 is an arrangement of shoulder 42 and is preferably such that the diaphram 43 can travel a distance of approximately 20% of the internal diameter o spacer 32 with a contE~ct of a disc 47 on the end of a loading coil spring 46 against an open edge of shoulder 42 stopping further vertical diaphram traveL The diaphram is constructed to withstand flexure damage by design of the shape of the elastomeric 30 material and appropriate selection of a high tensile strength fabric reinforcement, which elastomeric material is arranged beneath the spring casing base 30a across the loading chamber 35 interior, and maintained at its edges that are sandwiched between that base and the spacer 32. The spring casing base 30a, diaphram spacer 32, the throtting plate 33 and the flanged portion of valve body 31 a~l have holes formed `2C~

through corners thereoî that align to receive bolts 34 fitted therethrough for clamping the components together when nuts 34a are turned therover. ?3ealing of the components together, at the corners, is preferably provided by a utilization of appropriate gaskets or 0-rings arranged at component junctions prior to their bein~
05 clamped together. So assembled, the diaphram 43 is free to flex vertically within the cavity 41, flexing at its junction between the spring casing base 30a undersurface and spacer 32 between the cavity shoulder 42 and where the throttling element 44 engages the throttling plate 33. In practice, a tabric reinforced elastomeric material manufactured by Bellofram Corporation identified as a nitrile/polyester or Buna lO N/polyester has been found to provide a material having the desired characteristics o flexure and high tensile strength for covering diaphram 43 and forming throttling element 44.
Fig. 3 shows, u throttling element 44 bonded to the undersurface of diaphram 43 that is aligned to cover over openings 45 formed through throttling plate 15 33. The arrangement of which openings 45 are shown as preferably mirror images of one another across solid center portion 39 thereof and will be discussed in detail later herein with respect to Figs. 4, 5, 6. It should, however, be understood that a flow pattern with non-semetrical openings may alternatively be selected and the area surrounding the openings may be relieved as iUustrated in Fig. 4A. The preferred 20 throttling element is one made of the same elastomeric materidl that coats the diaphram though it should be understood that the throttling element could be formed separately from the diaphram and bonded thereto within the scope of this disclosure.
And where nitrile has proven satisfactory in practice for both diaphram ~oating and formation of the throttling element, it should be understood that any elastomer 25 capable of flexure such that the throttling element will uniformly lift or peel off of the throttling plate openings as described, that will close tightly in sePling engagement over said holes but will not to extrude ineo those throttling plate holes or openings, would be satisfactory. In practice, a solid throttling element 44, as described, has besn used, and in another embodiment, a throttling element that incorporates parallel 30 spaced ribs molded or implanted into the throttling element, across the flow path hes 50 been utili~ed. Such a rib throttling plate is shown in Figs. 7, 9 and 10 and will be explained in detail later herein.
The above described diaphram 43 that includes the throttling element 44 provides for closing off openings 45 formed through the throttling plate 33. Such 35 Closure is responsive to the described pressure differential in conjunc~ion with a spring _g_

2~

loading biasing,. Tlle preferrcd sE~ring as shown best in Fig. 3, is in this embodiment is Goil spring 46 that is supl)orted within tlle spring casing, posit,oned wiihin thc I aading chamber 35 between disc 47 that, rest~ on the surface of diaphram 43 opposi~e to throttling element 44, and a platl3 48, that is secured across a spring upper end. Plate 05 48 vertical positioning within the londing charrber translates to spring compressive loading nnd is adjusted by turning of an adjusting screw 49 that is turned through A top end 30a of the spring casing 3~, to move an end 49rl against that plate and contAct of disc ~7 with th-: o?ening ~hrough ch~mber shonlder 42 llmiting vertical travel Or the coil spring 46 and diaphram 43. The screw preferably includes a head 49b for a fitting lO a tool thereto for turning that adjusting screw 49 to appropriately compress or expand the soring, providing an udjustment c~pability to the loading force exerted t~y the coil spring 46 against diaphram disc 47. Dinphram loading is therefore a resultant of the pressure diffeierltial P2 ~ P3, the loading force exerted by coil spring 4~, and the ptessure differcntiai P3-P4. The position of the throttling element 44 rel~tive to the !.5 throttling plate 33 is thsrefore governed by the combination of the coil spring force in conjunction with the pressure diff3lentials Pressure P3 could be generated otherwise than with pilot ~ystem 23, as shown in Fig. 1, ns frorn an independant source, not shown, either liquid or gaseous, provided that such pressure source is equal to or greater than the inlet nuid pressure Pl. Additionally, while a coil spring 46 has been 20 shown and described herein as preferred, it should be understood that any spring arran~ement could be so used within the scope of this disclosure and in other embodiments of ~igs. 3 and 10, a different spring configuration is shown that will be described in detail l~tter herein.
As set out above, thc flowgrid regulator of ths presellt invention provides 25 for a selection of a throt-ling plate to achieve certain flow cllarac-teristics. Figs. 4, 4a, 5 and 6 show three different ernbodiments of throttling plates 33 that each including a center closed area 39 that, as set out above, aligns with the flat edge end 38 of barrier 37. The throttling plate includes, on either side of the closed area 39 complimentary groups of openings therethrollgh that are mirror image3 oE onè another, 30 although other non simPtrical arrangements are also possible withirl the scope of tnis disclosure. Fig. 4 shows as openings small holes S1 whercthrough the flow will be divided into smaller flows resulting in control of the damaging effects of cavita~ion which occurs at high pressurc drops and in Fig. 4R. the area surrounding holes 51 csn, like area 39, also be relieved. Whereas, in Fig. 5 the ima~e openings 52 are shown to ba larger diameter holes that are spaced relatively far apsrt. This nrrangement provides A reduction in flow capacity as compared to the throttling plate of Figs. 4 and 4A and a throttling plate of 6. In Fig. 6 is shown a throttling plate that is arranged to provide a high capacity flow therethrough, by an arrangement of longitudinal openings 05 53 formed therethrough in the line of flow, which openings have a greater open area as compared to either of the throttling plates of Figs. 4 and 5.
Hereinabove, are set out three different embodiments of throttling plates for providing a different flow capacities and characteristics therethrough with arms around those openings appropriately relieved as shown in Fig. 4A to control the area of seal engagement. It should be understood however, that a number of configurations of openings, that are preferrably but not necessarily mirror images, across a center closed or solid area, could be employed within the scope of this disclosure.
Fig. 7 shows a top plan view of another diaphram 55 with a throttling element 56 secured or integral thereto, which arrangement is essentially like the diaphram 43 and throttling element 44 shown and described hereinabove with respect to Fig. 3. Except, however, the throttling element 56 of this embodiment is shown to include ribs 57 embedded or implanted therein so as to lie parallel and spaced apart with one another and extending laterally across a flow path. The ribs are preferably straight small diameter sections of steel rod, heavy wire, or the like and are preferably implanted therein during the molding process forming the diaphram. This arrangement of ribs is shown also in the profile sectional view of another embodiment of the flowgrid regulator that is shown in Fig. 9. The ribs 57 are shown therein as spaced equally apart and essentially co-planar through a horizontal center of that throttling element. As with the earlier described throttling element, 44, a pressure differential will cause the throttling element 56 to lift off the throttling plate, the ribs providing lateral reinforcement and allowing for a smooth rolling or peeling action of the throttling element lifting off from the throttling plate. Where, the throttling element 44 of the embodiment of Fig. 3 must be sufficiently stiff to avoid beingextruded into the holes or openings in that throttling plate, the throttling element 56 of Fig. 7, need not be formed of as stiff a material, the ribbing providlng both a reinforcing and a bonding of th~t material to discourage extrusion through the throttling plate openings or holes. As with the earlier diaphram ~3 snd the described throttling plates, the disphram 55 includes holes 55a formed through the corners thereof for aiignment and receipt of bolts 34 installed therethrough to sandwich, in sealing engagement, the diaphram between a spacer and throttling plate.
In Fig. 8 is shown another arrangement of n valve body 58 of the flowgrid regulator. This valve body includes a right angle section 59 that redirects a flow 05 through the flowgrid regulator at a right angle thereto. Except for the right angle section 59 the fiowgrid regulator Fig. 8 is like that shown and described with respect to Fig. 3, and therefore that portion has been broken away.
Fig. 9 shows another embodiment of a fiowgrid regulator 60 that is essentially like flowgrid regulator ao of Fig. 3 except that it utili~es another 10 embodiment o a spring casing and loading spring therewith It should be understood that either of the described diaphramst throttling elements therefore, and throttling plates could be used ns components of the flowgrid regulator 60 of Fig. 9. Therefor, for illustration, the diaphram 55 of Fig. 7 that includes throttling element 56 with ribs 57 implanted is shown included with this flowgrid regulator 60. Where ~s discussed, 15 the flowgrid regulator 20 of the Fig. 3 employs an elongate spring casing 30 for housing the coil spring 46, spring casing 62 of this embodiment is essentially flat to accomodate, an embodiment of an elliptical spring 61 therein. 'rhe elliptical spring 61 is an arrangement of two bowed leaf springs 63a and 63b that are joined at their ends 64 by pivot couplings. In this embodiment, the lower bowed leaf spring 63b is bent or 20 flexed directly against the diaphram upper surf~ce, opposite to the throttling element bonded therebelow. The elliptical spring 61 provides a centered application of force against the diaphram that urges the throttling element into covering engagement with throttling plate and functioning of this throttling element is similar to the functioning of throttling element 44 of Fig. 3.
In Fig. 10 is shown another embodiment of an elliptical spring 70 that like eliiptical spring 61 is an arrangement to a pair of upper and lower leaf springs 71a and 71b connected at their ends, preferably by pivot couplings 72. Additionally, elliptical spring 70 includes a third leaf 73 centrally secured, as by rivets 74, or the like to lower leaf spring 71bt the leafs bowed oppositely from their center coupling. Additionally, 30 the thir~ leaf 73 ends are preferably bowed at 75 oppositely to the center bow providing points of contact for engaging the diaphram upper surface above points on opposite sides ol the throttling element and in the line of the flow. In this embodiment thereby, the spring loading is transmitted to the throttling element ends concentrsting the spring loadlng force at the points where the throttling element will ~irst lift o~ the throttling plate.
In the embodiment of Fig. 9, with the elliptical spring 61 shown therewith or the elliptical spring 70 of the embodiment of ~ig. 10, the spring force generated by 05 the elliptical spring arrangement is governed by the height of cavity 62a. As with the embodiment of Fig. 3, flowgrid regulator 60 of Fig. 9 is assemblied by fitting bolts, as shown in broken lines, through openings therethrough and turning nuts thereover.
Flowgrid regulator 60 also includes an inlet port 65 that, like the inlet port 40 of the embodiment of Fig. 3, is for connection to a pilot system. By providing a flatter 10 loading chamber and elliptical spring arrangement, as described, the flowgrid regulator 60 will exhibit greatcr dynamic stiffness and stability. These characteristics are especially effective for controlling compressible fluids and, of course, the flowgrid regulator 60 will take up less space than its counterpart of Fig. 3.
Fig. 11 shows a combination of two throttling elements conneeted to 15 opposite sides of a single valve body 66. The single valve body of this embodiment includes a barrier 67 that is like a mirror iMage of the barrier 38 of ~ig. 3, opposite ends ot that barrier intersecting the solid areas 69 of throttlin~ plates 68. The throttling plates 68 are component parts of flowgrid regulators attached thereto that are preferably like the flowgrid regulator 20 of Fig. 3. There~ore, it should be 20 unùerstood the only material distinction between the arrangements of Fig. 3 and Fig. 11 is in the valve body 66 configuration with barrier 67 therein. The arrangement shown in ~ig. 11 has a number of potential applications, as for example: both units can be controlled by the same pilot system providing thereby for an increased capacity.
Alternately, separate pilots could be used to provide system redundancy, should it be 25 desired, or to respond to different process variables such as flow, level or temperature.
The present invention in a flowgrid regulator has been shown and described to oper~te with a pilot system that is connected to provide a pressure within a spring casing that will be eql;al to or less than the inlet pressure to that flowgrid regulator to 30 effect functioning. Therefore, it should be understood, that the present invention can be used with any independent pressure source connected to the pilot system so long as that pressure Is equal to or greater than the Inlet fluid pressure. Additlonally, while several embodiments of throttling plates are shown and described herein, it should be understood that any number oî different throttling plate configurations could be so ~, ~ r-.V~

used within the scope of this disclosure. And, while several embodiments of spring biasing arrangements have been shown and described, it should be understood thnt other spring arrangements would be appropriate for incl!usion therewith. Also, while two embodiments of throttling elements have been shown and described herein, it 05 should be understood that any throttling element, functioning as described, for arrangement with the flexing diaphram could be substituted for the described structure. And while a diaphram constructed of a elastomer reinforced with fabric forming also the throttling element, as manufactured by Bellofram Corporation identified as nitrile/polyester has been disclosed herein as preferred, other like 10 materials may be used within the scope of this disclosure, providing that such arrangement results in a diaphram that is flexible but non stretchable.
Herein has been described a preferred arrangement of a flowgrid regulator and the components thereof. It should however be understood the present disclosure is made by way of example only and that changes can be made thereto without the 15 departin~f from the subject matter coming within the scope of the following claims, which claims I regard as my invention.

Claims (10)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY
OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A bidirectional flowgrid regulator comprising, a valve body that includes a dividing barrier equally separating inlet and outlet flow passages; a throttling plate covering said flow passages and the dividing barrier, said throttling plate having openings therethrough that are holes or slots aligned with the direction of flow through said flow passages to receive fluid therefrom; a diaphragm formed of a flexible non-stretch-able material that includes a centrally fixed throttling element on one face thereof, said diaphragm arranged to enable said throttling element to move into and out of sealing engagement over said openings in said throttling plate; a spring casing attached to said valve body by spring casing attachment means, said spring casing arranged over an upper surface of said diaphragm opposite to said throttling element; leaf spring biasing means arranged in said spring casing for urging said throttling element of said diaphragm into sealing engagement over said openings in said throttling plate, said leaf spring biasing means composed of a pair of first and second oppositely bowed elliptical spring leaves that face each other and are joined together at their ends to define an ellipse, said second leaf being located between said first leaf and said diaphragm, with a third elliptical spring leaf located between said second leaf and said diaphragm, said third elliptical leaf having a center portion and two free ends and is connected at said center portion to a center portion of said second leaf of said pair of leaves, each of said third leaf free ends is arranged to contact said upper surface of said diaphragm at a location adjacent to an edge of said throttling element and on opposite sides of said dividing barrier; and an inlet means into said spring casing that provides communication between said spring casing and a source of pressurized fluid that provides loading pressure for urging said throttling element of said diaphragm into sealing engagement against said throttling plate openings.

2. A flowgrid regulator as recited in claim 1, further including a spacer means for arrangement between the throttling plate means and the diaphragm means.

3. A flowgrid regulator as recited in claim 1, wherein the valve body dividing barrier has a flat edge surface for engaging a solid center area of the throttling plate means; and the throttling plate means openings are on both sides of said solid center area.

4. A flowgrid regulator as recited in claim 1, wherein the non stretchable material of the diaphragm is a fabric that is coated on both sides with an elastomer.

5. A flowgrid regulator as recited in claim 4, wherein the diaphragm non stretchable material is nitrile/polyester manufactured by Bellofram Corporation.

6. A flowgrid regulator as recited in claim 1, wherein the throttling element of the diaphragm means is integral thereto and is formed from the elastomeric material and dimensioned to fit over the throttling plate openings to provide a sealing engagement across said throttling plate openings.

7. A flowgrid regulator as recited in claim 6, further including spaced apart parallel ribs implanted centrally, at spaced apart intervals in the throttling element, said parallel ribs are co-planar and extend across and above the flow path through the throttling plate.

8. A flowgrid regulator as recited in claim 1, wherein the bowed leafs are pivotally coupled at their ends.

9. A flowgrid regulator as recited in claim 1, wherein the third leaf free ends are bent away from the diaphragm means.

10. A flowgrid regulator as recited in claim 1, wherein the pressure source is provided by a pilot system that is responsive to a process variable to provide a loading pressure within the spring casing to operate the flowgrid regulator to pass a flow therethrough.