CA2357912A1

CA2357912A1 - Multi-pressure ball-poppet control valve

Info

Publication number: CA2357912A1
Application number: CA002357912A
Authority: CA
Inventors: Charles A. Weiler, Jr.
Original assignee: Ross Operating Valve Co
Current assignee: Ross Operating Valve Co
Priority date: 2000-09-27
Filing date: 2001-09-26
Publication date: 2002-03-27
Also published as: DE60122445T2; JP2002188739A; KR20020025054A; MXPA01009729A; CN1232737C; DE60122445D1; TW554139B; BR0106624B1; BR0106624A; EP1193401A3; ES2269268T3; CN1346026A; EP1193401A2; EP1193401B1; US6431209B1

Abstract

A high-pressure primary fluid control valve and a multi-pressure selector fluid control valve are disclosed for operating a fluid-actuated device. Preferably a spherical ball-poppet and frusto-conical valve seat adapted for substantially line-contact therebetween are provided with an upstream flow area adjacent the line-contact in order to substantially minimize sonic flow damage to the actual sealing surface of the valve seat by shifting it away from such line-contact seating. Preferably, the ball-poppet is movable within a poppet guide that is allowed to float radially in order to allow the ball-poppet to be substantially self centering with respect to the valve seat. In addition, cross-over leakage is preferably negated by closing an exhaust ball-poppet just prior to opening a supply ball-poppet. These principles and features are equally applicable to either or both of the primary or the multi-pressure selector fluid control valves.

Description

IVIULTI-PRESSURE BALL-POPPET CONTROL VALVE
This application is a continuation-in-part of copending application Serial No.
n9/527,395, filed March 16, 2000.
BACKGROUNDAV1D SL:TIvflvIA~ty OF THE INVENTION
The invention relates generally to fluid control valves for operating a fluid-actuating device and more gartieularly to either selector or primary fluid control valves employixlg one or morn ball-poppets, Although the principles of the invention are applicable to both pneumatic and liQuid fluid control valves, it is especially applicable to hign~-pressure pneuFnatic control valves, as well as to suclj pneum.atie controls adopted far selective switching between turo..or more different outlet pressures.
A variety :of fluid control valves, especially those of the pneumatic nature, have been provided for numbrous high-pressure applications, including those used in processes for blow-molding plastic bottles or other such containers. Althougl:.such control valves have generally functioned satisfactorily for the processes to which they have: been applied, they have been found to be subject to excessive wear due to the high working fluid pressures involved and thus have had ~ relatively sHort life span. In addition, also in part due to the high pressures of the actuating fluids, such previpusly-provided fluid control valves have been subject to an unacceptable level of internal working fluid leakage, such as cross-over leakage that occurs when opening a supply portion of the valve and closing an exhaust portion of the valve in order to admit working fluid to the fluid-actuating device. As a result, both of these factors have contributed to the high operation costs and high maintenance costs of the systems in which the previously-provided fluid control valves have been used.
In addition, many applications require the capability of selecting between rivo or more contxol valve outlet pressures, especially in pneumatic systems. One example of such an application is the .above-mentioned processes for blow-molding plastic bottles or other such vessels or containers. In these exemplary processes, it is often desirable or necessary to initially admit a relatively lower pressure to the mold in order to introduce the plastic (or other material}
into the mold cavity or cavities and then to admit a relatively higher pressure to force or Expand the material into the desired shape dictated by the shape of the mold.
Therefore the present invention seeks to provide an improved high-presswre or multi-pressure fluid conCrol valve that is significantly less subject to wear and that substantia.Ily nenates internal working fluid leakage, thus contributing to the long life of the fluid control valve and reducing both system operating and system maintenance costs. Furthermore F;he present invention also seeks to provide such a control valve capable of selectively delivering two or more different pressures to the process system.
In accordance with the present invention, a primary control valve for operating a fluid-actuated device pzeferably has an inlet in communication with a source of pressurized working fluid, an outlet paøsageway and port in fluid communication with the fluid-actuated device, and a fluid supply passage providing fluid communication for th.e working fluid fiom the inlet to the outlet. The control valve preferably includes a generally fmsto-conical supply valve; seat in the fluid supply pass$ge with the supply valve seat having a srxxaller-diameter downstream end and a larger-diameterupstream end. A generally spherical supply poppet or supply bah',-poppet is I
selectively movable betweewrespective supply closed and supply open positions, into and out of a substantially dine-contact for sealing with the smaller-diameter end of the supply valve seat.
The spherical supply ball-poppet has a chord dimension at such line-contact with t:he smaller diameter downstream end of the valve seat that is smallEr than the larger-diameter upstream end of the supply valve seat. This arrangerrlent can also be used in a pressure selector fluid control valve according to the present invention, as described below.

Each side of the preferred frusto-conical supply valve seat has a supply seat angle relative to the centerline o~ the supply valve seat that is greater than an angle formed by the: centerline of the supply valve seat and a line tangent to the supply ball-poppet at the above-mentioned substantially line-contact when the supply ball-poppet is in its closed position. The included angular relationship of the valve seat angles on both sides of the centerline is preferably approximately ninety degrees. This results in a annular space being formed between the supply valve seat and the spherical supply ball-poppet, which defines a restricted supply flow area upstream of the a>_tove-mentioned substantially line-contact as the supply ball-poppet initially moves to its openposition and as high-velocity and high-pressure working fluid initially flows downstream past the supply ball-poppet through the smaller-diameter end of the valve. seat. This is greatly advanta.~eous because any sonic flow erosion caused by the initial flow of the high velocity and high-pressure working fluid through the annular restricted supply flow area is thus shifted substantially immediately to an upstream surface of the supply valve seat that is adjacent to such annular restricted supply flow area. Most significantly, such upstream sur:Eace of the supply valve scat ~s an area that is not sealingly contacted by the supply ball-poppet. Therefore, this immediate shifting of the sonic damage-susceptible area substantially minim~,izes sonic erosion of the nearly "lrnife-edge" smallex-diameter downstream end of the supply valve seat that is substantially line-contacted by the supply ball-poppet. In control valves according to the present inventiox~that have both supply valuing and exhaust valuing, a similar arrangement is preferably provided in the exhaust passage way in fluid conmmnication for e;~haust fluid between the load outlet passageway (and load outlet) and the exhaust outlet. As mentioned above, this arrangement is ecjually applicable to a pressure selector fluid control valve, as described below.
in addition, the present invention preferably includes a generally cylindrical cavity immediately upstream of the larger-diameter upstream ends of the supply and/or exhaust valve seats, with such cavity preferably being larger in diameter than the larger-diameter upstream end of the respective valve seats. A cylindrical poppet guide or ball-poppet guide is located in this enlarged-diameter cavity of the fluid passageway, with the ball-poppet guide having a central guide bore extcnd~ng axially therethrough. A numbor of eircurnferentially spaced-apart axially extending guide ffns protrude radially inwardly into the guide bore, with the ball-poppet being received within the guide bore for axial movement within radially inward edges of tl~:~e guide fins s between its open~'and closed positions. The inner diameter of the above-mentioned cavity is preferably slighthy greater than the outer diameter of the ball-poppet guide in order to allow the ball-poppet guideiand the ball-poppet to float radially somewhat within the cavity. This allows the generally spherical ball-poppet to be substantially self centering for sealing line-contact with the smaller-diameter end of the respective supply or exhaust valve seat. Such circutnferentiallv spaced guide finsi allow high pressure working fluid to ilow therebetween, and the ball-poppet guide substantially nunimizes wear on the ball-poppet andfor the valve seat that would result if it were to be allojwed to rattle or otherwise move radially in the high-velocity fluid flow. Such .. i a ball-poppet guile can also be used in a selector fluid control valve, as described below.
The presexit invention substantially also negates cross-over leakage in high-pressure fluid control valves having both supply and exhaust valuing by energizing the exhaust ball-poppet actuator, thus closing the exhaust side of the control valve, just prior to energizing the supply ball-poppet actuator, which then opens the supply side and initiates supply flow to the load passageway and port.
The above-mentioned ball-poppets (for either primary or selector fluid conixol valves}
are pxeferably composed of a metallic material, such as a stainless steel, for example, and the above-mentioned bail-poppet guides are preferably composed of a synthetic material, such as nylon, for example. Those skilled in the art will readily recognize that other metallic, synthetic, or non-synthetici materials can also be Employed for the ball poppets and/or the ball-poppet guides, dependir~g upon the particular working fluid {pneumatic or liquid) being employed, as well as the particular working fluid pressures involved, as well as depending upon the particular application in which the fluid oontrol valve of the present invention is err~ployed.
The present invention also provides a pressure selector fluid control valve fo:r selectively supplying at least two different working fluid pressures to a fluid-actuated device, either directly or by way of a primary fluid control valve, such as that discussed above. An exennpllary selector fluid control valve according to the present invention preferably has a high-pressure inlet in fluid communication with a source of working fluid at a relatively high pressure, a low-pressure inlet in fluid communication with a source of working fluid at a relatively low pressure, and a load fluid outlet passageway interconnected in fluid communication with the fluid-actuated device or primary fluid ;control valve inlet. Such a selector fluid control valve further includes a normally closed high-pressure valve mechanism in fluid communication between the high-pressure inlet and the load fluid outlet passageway to selectively allow high-pressure fluid flow from the high-pressure inlet to the load fluid outlet passageway, a.s well as a normally open low-pressure valve mechanism in fluid communication between the low-pressure inlet and the load fluid outlet passageway to selectively allow low-pressure fluid flow from the low-pressure inlet to the load fluid outlet passageway. A pilot actuator is pxovided and is selectively operable to force the normally closed high-pressure valve mechanism unto an open position and allow said high-pressure fluid flow fxom the high-pressure inlet to the load fluid outlet passageway. This high-pressure fluid being admitted into the load fluid outlet passageway forces the normally open low-pressuYe valve mechanism into a closed position to prevent fluid flow between the low-pressure inlet and the load fluid outlet passageway. Thus tlz.e selective actuation or energization of the pilot actuator, either the high-pressure or low-pressure working fluid (such as a pneumatic working fluid, for example) can be admitted to the inlet of a fluid-actuated device or the inlet of a primary fluid control valve, such as that described above or of virtually any type.

At least oz~e or preferably both of the above-discussed high-pressure and law-pressure valve mechanisms can include a generally fnzsto-conical valve seat located in a valve fluid passageway in fluid communication with the load fluid outlet passageway, with the valve seat having a smaller-diameter downstream end and a larger-diameter upstream end.
.A generally spherical ball-poppet is selectively movable between respective closed and open positions into and out of substantially ball-poppet line-contact for sealing with said smaller-diameter end of the supply valve seat.; The generally spherical ball-poppet preferably has a chord dimension at said line-contact with the smaller-diameter downstream end of the valve seat that is smaller than the larger-diameter upstream end of the valve seat. The generahy fi-usto-conical valve seat preferably has a seat angle relative to the centerline of the supply valve seat that is ,greater than an angle formed by the centerline of the valve seat and a line tangent to the spherical ball-poppet at the ball-poppet line-contact when the ball-poppet is in said closed position, with such seat angle preferably being approximately forty-five degrees such that the overall seat angle between diametrically opposite portions of the valve seat is approximately ninety degrees. An annular space formed bEtuieen the valve seat and the spherleal ball-poppet thus defines a restricted flow area upstream of the ball-poppet line-contact between the sphezical ball-poppet and the smaller-diameter downstream end of the valve seat as the sphezical ball-poppet initially moves out of said line-contact to its open position and as the working fluid initially flows downstream past the ball-poppet through tie smaller-diameter end of said valve seat. By such an arrangement, any soxzic flow erosion caused by the initial working fluid flow past the opening ball-poppet is shifted substantially imr~icdiately to an upstream area of the valve soar that is adjacent the restricted flow area and that is not sealingly contacted by the spherical ball-poppet. This substantially minimizes sonio.damage to the smaller-diameter downstream end of said valve seat against which the ball-poppet is sealingly engaged when in its closed position. This greatly increases the life of the control valve by minimizing the wear on the sealing portion of the valve seat.

One or both of the fluid valve passageways can include a generally cylindrical cavity immediately upstream of the larger-diameter upstream end of the valve seat, the cavity being larger in diameter, than the larger-diameter upstream end. The valve m.echanisrru preferably includes a generally cylindrical ball-poppet guide located in the cavity of said fluid passageway, with the ball-poppet guide having a central guide bore extending axially therethrouglh. The ball poppet guide preferably has a number of circumferentially spaced-apart axially-extending guide I
fuss protruding radially inwardly into the guide bore, with the ball-poppet being received within the guide bore for axial movement within radially inward edges of the guide fins between its open and closed p,bsitions. The inner diameter of the cavity is greater than the outer diameter of the ball-poppet guide in order to allow the ball-poppet guide to float radially within the cavity and to allow the spherical ball-poppet tv be substantially self centering for sealing line-contact with the smaller-diameter end of said frusto-conical valve seat.
In any of the primary or pressure selector fluid control valves according to the present invention, the fru~to-conical valve seat can alternatively be located in a replaceable valve seat disc that is of a h~.rder material than that of the salve body.
Additional objects, advantages, and features of the present invention will become apparent from the following description and the appended claims, taken in conjunction with the accompanying drawings.
i 24 Figure 1 is a cross-sectional illustration of an exemplary fluid control valve according to the present invention.
Figure 2 ~s an end view of the fluid control valvo of Figure 1.
Figure 3 ~s a top view of the fluid control valve of Figures 1 and 2, with the top cover or cap removed.

Figure 4 i~ a top view of a ball-poppet guide for use with either or both of a supply ball-poppet and an exhaust ball-poppet of the control valve of Figure 1.
Figure 5 i~ a side view of the poppet guide of Figure 4.
Figure 6 i~ an enlarged detail view ofthe supply valuing portion of the control valve of Figure l, with the supply ball-poppet shown in its closed position.
Figure 7 i~ an enlarged detailed view similar to that of Figure G, but illustrating the supply ball-poppet in its;initially opening condition.
Figure 8 i~ an enlarged detail view of the exhaust valuing portion of the control valve of Figure 1, with the exhaust ball-poppet shown in its closed position.
Figure 9 i~ an enlarged detail view sizx~.ilar to that of Figure 8, but illustrating the exhaust ball-poppet in its iinitially opening condition.
Figure 10is a cross-sectional illustration of an exemplary dual-pressure selector fluid control valve according to the present invention.
, i . ..
Figure l0a is a cross-sectional view taken generally along line 1 Oa-l0a of k'igure 10.
Figure 11~ is a top view of the exemplary dual-pressure selector fluid control valve of Figazre 10, operatively interconnected with a primary fluid control valve, such as is illustrated in Figures 1 throug3i 9, both of which being mounted on a fluid manifold.
Figure 12. is a front view of the fluid control valve arrangement of Figure 11.
Figure 13is an end view of the fluid control valve arrangement of Figures 11 and 12.
Figure 14i is a cross-sectional illustration of an exemplary pressure selector fluid control valve similar to that of Figure 10, but showing an alternate ta-i-pressure version of the selector fluid control vale.
Figure 15~ is an enlarged detailed view of an alternate version of the ball-poppet portion of a control valve according to the invention, having a replaceable valve seat disc and which is applicable to any of the fluid control valves of FigurES 1 through 14.

DETAZT,ED DESCRIPTTON OF THE PREFERRED EMBODIMENTS
Figures 1 through 15 illustrate exemplary high-pressure and multi-pressure primary and selector pneumatic control valves in accordance with the present invention.
Although the drawings depict such exemplary pneumatic fluid control valves for purposes of illustration, one skilled in the art gill readily recognize that the principles of the present invention are equally applicable to othez~ types of primary or selector fluid control valves, as well as to fluid control valves for either laneumatic or liquid working fluids.
Tn Figure 1, an exemplary primary fluid control valve 10 includes a body 12, a pilot cap 14, both of which can, be secured to a.m,anifold 16 by way of a number of bolts 18, as well as being capable of alternate interconnection by way of fluid piping without the use of the manifold 16 if threaded ports are alternately provided.
The exemplary primary control valve 10 includes an inlet port 20, an outlet or load port 22, and an. exhaust port 24. A working fluid supply passageway"28 provides working fluid communication from the inlet port 20 to the outlet port 22, which is connected, such as by way IS of the manifold l~, to a fluid-actuated device. Similarly, an exhaust passageway 30 provides exhaust fluid corrimunication between the load port 22 and the exhaust outlet 24.
In the exe;nplary primaty control valve 10, the supply and exhaust passageways 28 and 30 respectively include a frusto-conical supply valve seat 3G and a frusto-conical exhaust valve seat 46. The supply valve seat 36 includes a smaller-diameter end 38 and a larger-diameter end 40. Similarly theexhaust valve seat 46 includes a smaller-diameter end 48 and a larger-diameter end 50. A generally spherical supply ball-poppet 42 and a similar generally spherical exhaust ball-poppet 52 are provided for opening and closing movement with respect to their respective frusto-conical supply and exhaust valve seats 36 and 46.
The supply ball-poppet 42 is preferably movably actuated by way of a supply pilot actuator 80, which receives pilot air from a pilot air passageway 97, which is in turn connected in fluid communisation with a pilot air inlet 9G. Then the supply pilot actuator 80 is energized, it transmits the foxce of the pilot air on the supply piston $1, by way of a supply push rod 82. to urge the supply ball-poppet 42 away from the supply valve seat 36, thus opening the supply valuing portion of the control valve 10, When the supply pilot actuator 80 is deenergized, the ball-poppet a2 is feturned to its closed position under the influence of the inlet fluid pressure and a return spring 5$.
Similarly; the exhaust bail-poppet 52 is urged into its closed position with respect to the exhaust valve seat 46 by way of the energization of an exhaust pilot actuator 90, which acts to exert the force o~'pilot air on an exhaust piston 91, by way of an exhaust push rod 92, to the exhaust ball-poppet 52. Upon deenergization of the exhaust pilot actuator 90, the exhaust ball-poppet 52 is urged back to its open position under the influence of high-pressure working fluid in the exhaust passageway 30.
One skilled in the control valve art will readily recognize that actuators other than the exezxlplary elect~o-pneumatic supply pilot actuator 80 and electro-pneumatic e;shaust picot actuator 90, can; alternatively be employed. Such actuating devices could include electro-mechanical solenoids, either local or remote, mechanical motion transmitting devices, or a wide variety of other ~.ctuating devices well-known to those skilled in the art.
Referrir~ primarily to figures 6 and 7, the exemplary high-pressure fluid control valve 10 depicted in the drawings also preferably includes a generally cylindrical supply cavity 60 immediately upstz-eam of the larger-diameter upstream end QO of the supply valve seat 36. As illustrated in Figures 4 through 6, a generally cylindrical supply poppet guide 62 is provided upstream within the preferred diametrically-enlarged cylindrical supply cavity G0. The supply poppet guide 62 includes a generally cylindrical central supply guide bore 64 extending axially therethrough, with a number of circumferentially spaced-apart and axially-extending supply guide fins 66 protruding radially inwardly into the supply guide bore 64. The supply ball-poppet 42 is received witjiin the supply guide bore 64 for axial movement within the radially inward edges of the supply guide fms 66 between its open and closed positions with respect to the supply valve seat 36. As ~s perhaps best illustrated in Figures 6 and 7, the inner diameter of the supply cavity 60 is slightly greater than the outer diameter of the supply ball-poppet guide 62, thus i allowing the poppet guide 62 and the ball-poppet 42 to float radially within the supply cavity 60, which in turn alloys the generally spherical supply ball-poppet 42 to be self centering for scaling substantially line-contact 44 with the smaller-diameter end 38 of the supply valve seat 36.
In addition, the supply guide fins 66 preferably extend axially downstream to forni a supply guide fin ei~tension portion 63 on one end of the supply poppet guide 62. A resilient ring 61, such as an O-ring, surrounds the extension portion 63 in order to resiliently urge the poppet aide 62 toward g the opposite, upstream end of tl~e supply cavity 60, which is due to the resilient a ring 61 being coypressed between the floor of the supply cavity 60 and the remainder of the supply ball-poppet guide 62..
It should tje noted that the above arrangement, as depicted in Figures 4 through 7, is substantially typical with respect to the frusto-conical exhaust valve seat 46, with its smaller-diameter upstrear~n end a8 and its larger-diameter downstream end 50 for engagement in substantial line-contact of the sznallEr-diameter end 48 by the generally spherical exhaust poppet 52, all of which are shown in Figure 1. Similarly, the supply poppet guide 62 depicted. in Figures 4 and 5 is substazitially typical for the exhaust poppet guide 72, which is received within the s diametrieally~enl~rged generally cylindrical exhaust cavity 70 and has a similar cent~~al exhaust guide bore 74 and similar exhaust guide fins 76, and which can also be seen in Figures 1, 8 and 9.
Referring jin particular to Figures 6 and 7, which depict an enlarged detail view of the su 1 valvin pp y g portion of the exemplary control valve 10, the ball-poppet 42 is shown in its closed position i.~ Figure 6, rn this position, the ball-poppet 42 is sealingly engaged in substantial line-cqntact 44 with the edge of the smaller-diameter end 38 of the supply valve seat 36. Similarly, the ball-poppet 42 is sho~.vn partially opened and thus moved out of such substantial line-egntaet 44 in Figure 7. The frusto-conical supply valve seat 36 preferably has a valve seat anglei37 (with respect to the centerline S7 of tha valve seat 3G) that is slightly larger than the tangent angle 59 of the tangent line 56 to the ball-poppet 42 (with respect to the i centerline 57) when the ball-poppet 42 is in the substantial line-contact 44 shown iin Figure 6.
This arra~ement results in an annular space 43 creating a restricted'supply flow area just upstream of tile supply line-contact 44 and the smaller-diameter end 38 as the supply ball-poppet 42 initially moves out of such line-contact 44 to its open position shown in Figure T as working fluid initially flows downstream past the ball-poppet 42 through the smaller-diameter end 3 8 of the supply valve Seat 36. This results in any sonic flow erosion damage caused by such initial flow of high-pressure working fluid to be shifted substantially immediately to an upstream area 45 of the supply halve seat 36, This is highly advantageous in that it, shifts such wear or damage causEd by such spnic flow erosion ~to an area of the supply valve seat 36 that is adjacent the annular space 43 and that is never in sealing contact with the ball-poppet 42.
This substantially minimizes sonic damage to the smaller-diameter downstream sealing end 38 of the supply valve seat 36 which is ~e only valve seat area that is ever in substantial line-contact 44 with the ball-poppet 42. As aresult, the damage to and wear of the actual sealing surface of the valve seat 3G
on the ball-poppet 42 is very substantially minimized and the functional life of the exemplary control valve 10 ~s correspondingly greatly extended. This in turn very significantly reduces the downtime and the maintenance costs for a system employing a control valve 10 according to the present invention.
As will b~ readily recognized by one skilled in the art, that the above-described function of the ball-poppet 42 with respect to the supply valve seat 36 as shown in Figure 6 and 1~igure 7 is similar to thataf the function and relationship of the exhaust ball-poppet 52 with respect to the exhaust valve seat 46 with its smaller-diameter end 48 and its larger-diameter end 5U.
Referring primarily to Figures 8 and 9, the exemplary high-pressure fluid control valve depicted in th~ drawings also preferably includes a generally cylindrical exhaust cavity 70 5 immediately dowr~strcam of the larger-diameter downstream end SO of the exhaust valve seat 46.
A generally cylindrical exhaust poppet guide 72 (similar to that of the supply poppet guide 62 of Figures 5 and 6) is provided downstream within the preferred diametrically-enlarged cylindrical exhaust cavity 70. The exhaust poppet guide 72 includes a generally cylindrical central exhaust guide bore 74 extending axially therethrough, with a number of circumferentially 10 spaced-apart andaxially-extending exhaust guide fens 76 protruding radially inwardly into the exhaust guide bole 74. The exhaust ball-poppet 52 is received within the exhaust guide bore 74 for axial movement within the radially inward edges of the exhaust guide fins 76 between its open and closed positions with respect to the exhaust valve seat 46. The inner diameter of the exhaust cavity 7Q is slightly greater than the outer diameter of the exhaust ball-poppet guide 72, thus allowing the poppet guide 72 and the exhaust ball-poppet 52 to float radially within the exhaust cavity 7d, which in turn allows the generally spherical exhaust ball-poppet 52 to be self centering for sealing substantially line-contact S4 with the smaller-diameter end 48 of the exhaust valve seat 4G.
The exhaust guide fins 7G preferably extend axially upstream to form an exhaust guide fin extension poxtion 73 on the exhaust poppet guide 72. ?, xesilient ring 71, such as an O-ring, surrounds the extension portion 73 in order to urge the poppet guide 72 toward the opposite, downstream end~of the exhaust cavity 70, which is due to the resilient ring 71 being compressed beriveen the floor of the exhaust cavity 70. and the remainder of the exhaust ball-poppet guide 72.

Referring in particular to Figures 8 and 9, which depict an enlarged detail view of the exhaust valuing pprtion of the exemplary control valve 10, the exhaust ball-poppet S2 is shown in its closed position in Figure 8'. In this position, the ball-poppet 52 is sealingly engaged in substantial line-contact 54.with the edge ofthe smaller-diameter end 48 ofthe exhaust valve seat 46. Similarly, the bail-poppet 52 is shown partially opened and thus moved out of such substantial line-contact 54 in Figure 9. The frusto-conical exhaust valve seat 46 preferably has an exhaust valve seat angle 47 (with respect to the exhaust centerline 67 of the valve spat 46) that is slightly larger than the exhaust tangent anglo 69 of the exhaust tangent line G5 to the exhaust ball-poppet 52 (wiith respect to the centerline 67) when the ball-poppet 52 is in the substantial line-contact 54 shown in Figure 8.
This aiTat~gement results in an annular space 53 creating a restricted exhaust flow area just downstream ~f the exhaust line-contact 54 and the smaller-diameter end 48 as the exhaust ball-poppEt 52 initially moves out of such line-contact 54 to its initially opening position shown in Figure 9 as exhaust fluid initially flows downstream past the ball-poppet 52 through the smaller-diameter~end 48 of the exhaust valve seat 46. Thus in any sonic flow erosion damage caused by such initial i'low of lugh-pressure exhaust fluid to be shifted substantially immediately to an upstream flow area adjacent the exhaust valve seat 46. This is highly advantageous in that it shifts such weak or damage caused by such sonic flow erosion to an area that is never in sealing i contact with the ;ball-poppet 52. This substantially minimizes sonic damage to the smaller diameter upstxearii sealing end 48 of the exhaust valve seat 46 which is the only valve seat area that is ever in substantial line-contact 54 with the balhpoppet 52. As a result, the damage to and wear of the actua9 sealing surface of the valve seat 46 on the ball-poppet 52 is very substantially minimized and tl~,e functional life of the exemplary control valve 10 is correspondingly greatly extended. This itl turn very significantly reduces the downtime and the maintenance costs for a system employing a control valve 10 according to the present invc.-~ntion.

Referring pa~i.marily to 1~igure 1, the cross-over leakage of the exemplary fluid control valve 10 depicted irr the drawings is substantially minimized by energizing the: exhaust pilot actuator 90 to close the exhaust ball-poppet 52 just slightly prior to energizing the supply pilot actuator 80 to open~the ball-poppet 42 when high-pressure working fluid is to be admitted to the outlet or load port 22 in order to actuate a fluid~actuated device. Because of the equivpment and energy necessary to elevate the working fluid to such a high-pressure state, this greatly rEduces the operating costs 'that would otherwise result from excessive waste or exhaust of high-pressure working fluid. Sutrh high-pressure working fluid, which can be either pneumatic or hydraulic, 'but which is preferably pneumatic, is often in the range of 300 psig to 900 psig, and is typically l0 approximately 600 psig in the above-mentioned blow-molding processes.
Finally, either or both of the ball-poppets 42 and 52 are preferably composed of a metallic material, such as stainless steel or other metallic or non-metallic materials deemed advantageous by one skilled in t~e art for a given application. Similarly, either or both of the supply poppet guide 62 and the e~chaust poppet guide 72 are preferably composed of a synthetic material, such 15 as nylon, but can also be composed of a metallic material, such a stainless steel, or other suitable materials known to those skilled in the art.
Figures 1~ through 15 illustrate various versions of a selector fluid control valve that can be used either alone or in conjunction (on the supply side) With the primary fluid control valve discussed above i~ connection with Figures 1 through 9. Because many of the components of 20 the valves illustrated in Figures 10 through 1 S are either identical or substantially similar, at bast in function, with ~oso of the valves depicted in Figures 1 through 9, such components in Figures i thrnugh I5 area indicated by reference numerals that are the same as those in Figures 1 through 9, but which have two hundred, three hundred, ar four hundred prefixes.
rn Figures 10 through 1:1, an exemplary selector fluid control valve 2I0 includes a body i 25 212, a pilot cap 21 ~, both of which can be secured to a manifold 216 (as shown in Figures 11 through 13) in a manner siixiilar to that depicted above in connection with Figures 1 through 9.
Alternately, however, instead of a manifold 216, interconnection of the various ports could be accomplished by why of fluid piping without the usa of the rnanifold 216 by providing threaded ports in the base of the valve body 12.
i The exemplary selector fluid control valve 210 includes a relatively high-pressure inlet port 220 and a relatively lower-pressure inlet port 221, which are in fluid communication with separate sources o f working fluid at relatively higher pressures or lower pressures, respectively.
Such relatively higher pressures will be referred to herein as "high-pressure", and such relatively lower pressures v~ill similarly be referred to as "low-pressure".
A load fluid outlet passageway 228 extends through the body 212 of the selector fluid control valve 2101and is in fluid commuraication with an outlet load port 222.
The selector fluid control valve 210Eean be used either alone, or in combination with a primary fluid control valve, such as the primary fluid control valve 10 of Figures 1 through 9. In such an application, the selector fluid control valve 210 can have its load outlet port 222 interconnected in fluid r communication v~ith the inlet port 20 of the primary fluid control valve 10, either by fluid piping or by Way of theimanifold 216.
The selectbr fluid control valve 210 also includes a normally closed high-pre:>sure valve mechanism in fluid cornmunieation between the high pressure inlet port 220 and the: Ioad fluid outlet passageway 228. Similarly, a normally open low-pressure valve mechanism is in fluid communication Between the low-pressuze inlet port 221 and the load fluid outlet passageway 228. In the exer3aplary selector fluid control valve 210, the high-pressure valve rnechatlism i includes a frusto.iconieal valve seat 236, Which in turn includes a smaller-diamEter end 238 and :
a larger-diameter end 240. A ball-poppet 242, which is preferably genexally spherical in shape and configuration, engages the valve seat 236 in a substantially line-contact engagement, in a manner explaine,'d in more detail in connection with the valve seat 36 and the ball-poppet 42 of i Figures I through 9. Similarly, the low-pressure valve mechanism includes a valve seat 246 having a smaller-diameter end 248 and a larger-diameter end 250, with the low-pressure ball-poppet 252 engagipg the small-diameter end 248 in the same type of line-contact as is discussed above.
The high-pressure ball=poppet 242 is received within a high-pressure ball-poppet guide 2G2, which is sim~iar to the ball-poppet guide 62 of Figures 1 through 9. In a similar manner, the law-pressure ball-poppet 252 is received within a low-pressure ball-poppet guide 272. In terms of their radi~lly-floating and ball-poppet centering capabilities, the guides 262 and 272 are substantially iden>rical to the guides 62 and 72 of Figures 1 through 9. The only difference IO between the guides 2G2 and 272 and the above-discussed guides 62 and 72 is that the fins 266 and 276 do not necessarily extend axially beyond the end of their respective guides 262 and 272.
In such an arrangement, instead of the O-rings Gl and 71 of Figures 1 through 9, resilient wavy washers or spring wave washers 261 and 271 are provided to resiliently bias the respective guides 262 and 272 toward their respective proper positions within the respective guide bores 15 264 and 274. In substantially all other respects, however, 'the ball-poppet guides 252 and 272 perform in a substantially identical manner as the corresponding ball-poppet guides; 62 and 72 discussed above.
In the pr~ferred selector fluid control valve 210, tree high-pressure ball-poppet 242 is biased toward its; normally closed position by a return spring 258 acting on the ball-poppet 242 i 20 by way of a ball~poppet perch 275: A pilot actuator 2$0 is provided in connection with the high-pressure ball-poppet 242 and is selectively actuable to farce the ball-poppet 242 off of its respective valveseat 236 and into its open position, with. the pilot actuator 280 acting through the high-pressure actuating piston assembly 281 and the push rod 282.
In the low-pressure valve mechanism, the ball-poppet 252 is in a normally-open position 25 under the influence of the low-pressuro working fluid from the low-pressure inlet 221 acting on the ball-poppet 252 and against the biasing force of a law-force retaining spring 251. The low-pressure ball-poppet 252 is held in place by a retainer plug 249 having a generally U-shaped opening 278 extending therethrough, as is illustrated in Figure 10a, and the opening travel of the low-pressure ball-~oppet 252 is limited by its contact with a stop rod or pin 277 fixedly i interconnected with the retainer plug 249 and extending into the retainer plug passageway 278.
In operation, the selector fluid control valve 210 can be used to selectively supply one of two different pressures of working fluid (preferably a pneumatic working fluid) to either a fluid-actuated device or to the inlet of a primary eonixol valve (such as the primary fluid control valve 10 discussed above) by way of the outlet load port 222 of the selector fluid control valve 2I0. Initially, a sQuree of relatively low-pressure working fluid is supplied to the low-pressure inlet port 221 aid passes by the normally-open ball-poppet 252 to the load fluid outlet passageway 228 and the outlet load port 222. Such relatively low-pressure worh'ing fluid exerts sufficient force orb the low-pressure ball-poppet 252 to maintain it in. its open position against the biasing force of the low-pressure retaining spring 251 as long as fluid is flowing in the circuit.
Thus, in this cot?dition, as is illustrated in Figure 10, relatively high-pressure working fluid supplied to the high-pressure inlet port 220 is isolated from the relatively low-pressure working fluid in the load fluid outlet passageway 228 by the normally closed high-pressure ball-poppEt 242, which is forced against its respective valve seat 236 under the influence of the return spring i 258. Thus, in thia condition, such relatively low-pressure working fluid is supplied t:o the outlet f load port 222.
Howeveri, when it is desired to adrxiit relatively high-pressure working fluid to the load fluid outlet passageway 228 and to the outlet load port 222, the pilot actuator 280 is. selectively energized. It should be noted that the pilot actuator 220 can be pneumatically operated, electrically opEr~ted, or mechanically operated, for example.

The energi~ation of the pilot operator 280 causes the piston assembly 281 and the push rod 282 to force tl~e high-pressure ball-puppet 242 to its open position against the biasing force of the rettun spring 258 and the high-pressure fhud in the inlet 220. This opening of the high-pressure ball-poppet 242 allows relatively high-pressure working fluid from the high-pressure inlet port 220 to piss into the load fluid outlet passageway 228. The high-pressure working fluid now admitted into; the load fluid outlet passageway 228 acts (in conjunction with the low-force retaining spring Z51) to urge the normally opon low-pressure ball-poppet 252 to its closed position in sealing engagement with the valve seat 246. Tlzus, in this condition, the relatively low-pressure working fluid from the low-pressure inlet port 221 is isolated from the relatively high-pressure wcirking fluid in the load fluid outlet passageway 228, the retainer plug passageway 278, ;and the outlet load part 222. As mentioned above, this allows for selective supply of either tl~e relatively low-pressure working fluid or the relatively high-pressure working fluid from the outlet load port 222 to a fluid actuated device or to the inlet 20 of a primary valve such as that of tl~c primary control valve 10 illustrated in Figures 1 through 9. This latter 1 S arrangement is illustrated in Figures 11 through 13 where the selector fluid control valve 210 and the primary control valve 10 are mounted together on a manifold 216, which can alternately be replaced by separate fluid piping without the use of the manifold 216 if alternate threaded ports are provided.
In Figure; l4, an alternate embodiment of a selector fluid control valve according to the present invention is depicted far purposes of illustrating that the present invention is equally applicable to such control valves adapted for supplying more than two different working fluid pressures to a fluid-actuated device, either directly oz through a primary fluid control valve, such as the primary fl~id control valve 10 discussed above and shown in Figures 1 through 9. The selector fluid cor~ti'oi valve 410 in Figure 14 has numerous Components that are either identical or functionally s~.bstantaally.similar to those of the fluid selector control valve 210 in Figure 10.
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i In Figure I4, however, such corresponding components are indicated by reference numerals having four-hundred prefixes and a or b suffixes in the case of components that are identical with each other.
The body 412 of the selector fluid control valve 410 includes two of the above-discussed high-pressure inlets 420a and 420b, with two of the above-described pilot actuators 480a and 480b, each of which are separately and selectively operable to urge their respective ball-poppets 442a and 442b into their respective open positions. In virtually all other respects, however, the selector fluid control valve 410 operates in substantially the same manner as the above-described selector fluid eont~ol valve 210.
I0 The operaroional difference between the selector fluid control valve 410 and the selector fluid control valve 210 is that the pilot actuators 480a and 480b can be separately and selectively actuated or energised, or de-actuated or de-energized, in order to allow for the selective supply of three different .pressures or working fluid to the fluid-actuated device, by way of the load outlet port 422, either directly or by way of the above-mentioned primary fluid control valve. rt 15 should be noted that Figure 14 illustrates merely an exemplary mufti-pressure application of the present invention, and one skilled in the art will now readily recognize that any number of different~prcssures can be accommodated by the selector fluid control valve of the present mventian.
In Figure' 15, still another alternate arrangement of the present invention is depicted, in 20 which the resilient spring wave washer 361 is moved to an opposite position with respect to the ball-poppet guide than that depicted in Figure 10. In this arrangement, a replaceable valve seat disc 388, which includes the valve spat 336 therein, is trapped between the ball-poppet guide 3G2 and the downstream end of the guide bore 364. The valve seat disc 388 includes a chamfered edge 386 that isisealingly engaged by an O-ring 384 and is preferably composed of a harder i 25 matez~ial than that of the valve body. Such an arrangement allows for convenient replacement of a worn valve seat 33d by merely replacing the valve seat disc 388, without the necessity of discarding or re-machining the valve seat 236 of the body 212 in Figure 10.
Thus, one selector i fluid control valve' can be partially disassembled and repaired by such replacement of the valve seat disc 388 whip another selector fluid control valve is in service. Such repaired selector fluid control valve can then be maintained in reserve for immediate replacement of a worn selector fluid control valveithat is currently in service. It should be noted that a similar replaceable valve i seat disc can also; alternatively be used in conjunction with any of the valve mechanisms or arrangements shown in Figures 1 through 15.
Finally, the preferred pneumatic high-pressure working fluid or fluids can be at virtually l0 any pressure above that of the low-pressure working fluid, such as, for e~cample, pressures in the range of 300 psigito 900 psig, with one application requiring a high-pressure working fluid at i approximately 600 psig. Similarly, the low-pressure working fluid can be at virnzally any pressure lower th~.n that of the high-pressure working fluid, such as, for example, pressures in i _ the range of 10 ~sxg to 300 prig, with at lEast one application requiring such low-pressure 15 working fluid at ~ pressuxe of approximately 100 psig. Furthermore, as mentioned above, the primary fluid control valves and the selector control valves of the present invention have wide-ranging applieabi~ity in various liquid or pneumatic fluid control or actuation systems. One example of such an application is a pneumatic system for blow molding of plastic bottles or other containers, which requires a first relatively lower pressure to urge the plastic material into the 2o mold cavity, folljowed by a relatively higher pressure working fluid to complete the blow molding process by forcing the plastic material against the internal contours of the mold. One i skilled in the art will readily recognize, hove er, that this is merely one example of the many applications of th(e present invention.
The foregoing discussion discloses and describes merely exemplary embodimc;nts of the 25 present invention for purposes of illustration only. Orie skilled in the art will readily recognize:

' ~ CA 02357912 2001-09-26 fxom such discussion, and from the accompanying drawings and claims, that various changes, modifications, and:variations can be made therein without departing from the spirit and scope of the invention as ;defined in the following claims.
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Claims

1. ~A selector fluid control valve for selectively supplying at least two different working fluid pressures to a fluid-actuated device, said selector fluid control valve having a high-pressure inlet in fluid communication with a source of working fluid at a relatively high pressure, a low-pressure inlet in fluid communication with a source of working fluid at a relatively low pressure, and a load fluid outlet passageway interconnected. in fluid communication with the fluid-actuated device, said selector fluid control valve further having a normally closed high-pressure valve mechanism in fluid communication between said high-pressure inlet and said load fluid outlet passageway to selectively allow high-pressure fluid flow from said high-pressure inlet to said load fluid outlet passageway, and a normally open low-pressure valve mechanism in fluid communication between said low-pressure inlet and said load fluid outlet passageway to selectively allow low-pressure fluid flow from said low-pressure inlet to said load fluid outlet passageway, said selector fluid control valve further having a pilot actuator selectively operable to force said normally closed high-pressure valve mechanism into an open position and allow said high pressure fluid flow from said high-pressure inlet to said load fluid outlet passageway, said high-pressure fluid in said load fluid outlet passageway forcing said normally open low-pressure valve mechanism into a closed position to prevent reverse fluid flow between said high-pressure inlet and said low-pressure inlet.

2. A selector fluid control valve according to claim 1, wherein at least one of said high-pressure valve mechanism and said low-pressure valve mechanism is a ball-poppet valve mechanism.

3. A selector fluid control valve according to claim 1, wherein at least one of said high-pressure and low-pressure valve mechanisms includes a generally frusto-conical valve seat located in a valve fluid passageway in fluid communication with said load fluid outlet passageway, said valve seat having a smaller-diameter end and a larger-diameter end, and a generally spherical ball-poppet being selectively movable between said respective closed and open positions into and out of substantially ball-poppet line-contact for sealing with said smaller-diameter end of said supply valve seat, said generally spherical ball-poppet having a chord dimension at said line contact with said smaller-diameter end of said valve seat that is smaller than said larger-diameter end of said valve seat, said generally frusto-conical valve seat having a seat angle relative to the centerline of said valve seat that is greater than an angle formed by the centerline of said valve seat and a line tangent to said spherical ball-poppet at said ball-poppet line-contact when said ball-poppet is in said closed position, an annular space formed between said vale seat and said spherical ball-poppet defining a restricted flow area adjacent said ball-poppet line-contact between said spherical ball-poppet and said smaller-diameter end of said valve seat as said spherical ball-poppet initially moves out of said line-contact to its open position and as said working fluid initially flows past said ball-poppet, any sonic flow erosion caused by said initial working fluid flow thereby being shifted substantially immediately to an upstream flow area that is adjacent said ball-poppet line contact and that is not sealingly contacted by said spherical ball-poppet thus substantially minimizing sonic damage to said smaller-diameter end of said valve seat.

4. A selector fluid control valve according to claim 3, wherein said frusto-conical valve seat is located within a replaceable valve seat disc removably disposed within said valve fluid passageway.

5. ~A selector fluid control valve according to claim 3, wherein said seat angle relative to said centerline is approximately forty-five degrees, such that an angle between diametrically opposite portions of said valve seat is approximately ninety degrees.

6. ~A control valve according to claim 3, wherein said fluid valve passageway includes a generally cylindrical cavity immediately adjacent of said larger-diameter end of said valve seat, said cavity being larger in diameter than said larger-diameter end, said valve mechanism.further including a generally cylindrical ball-poppet guide located in said cavity of said fluid passageway, said ball-poppet guide having a central guide bore extending axially therethrough, said ball-poppet guide having a number of circumferentially spaced-apart axially-extending guide fins protruding radially inwardly into said guide bore, said ball-poppet being received within said guide bore for axial movement within radially inward edges of said guide fins between said open position and said closed position, the inner diameter of said cavity being greater than the outer diameter of said ball-poppet guide in order to allow said ball-poppet guide to float radially within said cavity and to allow said spherical ball-poppet to be substantially self-centering for sealing line-contact with said smaller-diameter end of said frusto-conical valve seat.

7. ~A control valve according to claim 6, wherein said frusto-conical valve seat is located within a replaceable valve seat disc removably disposed within said valve fluid passageway.

8. ~A control valve according to claim 6, wherein said valve mechanism includes a resilient biasing member for resiliently urging said ball-poppet guide toward one axial end of said cavity portion.

9. A control valve according to claim 8, wherein said resilient biasing member is a spring wave washer.

10. A control valve according to claim 1, wherein said high-pressure working fluid and said low-pressure working fluid are pneumatic working fluids.

11. A control valve according to claim 10, wherein said high-pressure pneumatic working fluid is at a pressure in the range of 300 psig to 900 psig.

12. A control valve according to claim 11, wherein said high-pressure pneumatic working fluid is at a pressure of approximately 600 psig.

13. A control valve according to claim 10, wherein said low-pressure working fluid is at a pressure in the range of 10 psig to 300 psig.

14. A control valve according to claim 13, wherein said low-pressure working fluid is at a pressure of approximately 100 psig.

15. A control valve according to claim 1, wherein said high-pressure working fluid and said low-pressure working fluid are both pressurized liquid working fluids.

16. A control valve according to claim 2, wherein said ball-poppet is composed of a metallic material.

17. A control valve according to claim 16, wherein said metallic material includes stainless steel.

18, A control valve according to claim 2, wherein said ball-poppet is composed of a synthetic material.

19. A pneumatic selector fluid control valve for selectively supplying at least two different working fluid pressures to a fluid-actuated device, said selector fluid control valve having a high-pressure inlet in fluid communication with a source of pneumatic working fluid at a relatively high pressure, a low-pressure inlet in fluid communication with a source of pneumatic working fluid at a relatively low pressure, and a load fluid outlet passageway interconnected in fluid communication with the fluid-actuated device, said selector fluid control valve further having a normally closed high-pressure ball-poppet valve mechanism in fluid communication between said high-pressure inlet and said load fluid outlet passageway to selectively allow high-pressure fluid flow from said high-pressure inlet to said load fluid outlet passageway, and a normally open low-pressure ball-poppet valve mechanism in fluid communication between said low-pressure inlet and said load fluid outlet passageway to selectively allow low-pressure fluid flow from said low-pressure inlet to said load fluid outlet passageway, said selector fluid control valve further having a pilot actuator selectively operable to force said normally closed high-pressure valve mechanism into an open position and allow said high-pressure fluid flow from said high-pressure inlet to said load fluid outlet passageway, said high-pressure fluid in said load fluid outlet passageway forcing said normally open low-pressure valve mechanism into a closed position to prevent reverse fluid flow between said high-pressure inlet and said low-pressure inlet at least one of said high-pressure and low-pressure valve mechanisms including a generally frusto-conical valve seat located in a valve fluid passageway in fluid communication with said load fluid outlet passageway, said valve seat having a smaller-diameter end and a larger-diameter end, and a generally spherical ball-poppet being selectively movable between said respective closed and open positions into and out of substantially ball-poppet line-contact for sealing with said smaller-diameter end of said supply valve spat, said generally spherical ball-poppet having a chord dimension at said line-contact with said smaller-diameter end of said valve seat that is smaller than said larger-diameter end of said valve seat, said generally frusto-conical valve seat having a seat angle relative to the centerline of said supply valve seat that is greater than an angle formed by the centerline of said valve seat and a line tangent to said spherical ball-poppet at said ball-poppet line-contact when said ball-poppet is in said closed position, an annular space formed between said valve seat and said spherical ball-poppet defining a restricted flow area adjacent said ball-poppet line-contact between said spherical ball-poppet and said smaller-diameter end of said valve seat as said spherical ball-poppet initially moves out of said line-contact to its open position and as said working fluid initially flows past said ball-poppet, any sonic flow erosion caused by said initial working fluid flow thereby being shifted substantially immediately to an upstream flow area that is adjacent said ball-poppet line-contact and that is not sealingly contacted by said spherical ball-poppet thus substantially minimizing sonic damage to said smaller-diameter downstream end of said valve seat, said seat angle relative to said centerline being approximately forty-five degrees, such that an angle between diametrically opposite portions of said valve seat is approximately ninety degrees, said fluid valve passageway including a generally cylindrical cavity immediately upstream of said larger-diameter upstream end of said valve seat, said cavity being larger in diameter than said larger-diameter upstream end, said valve mechanism further including a generally cylindrical ball-poppet guide located in said cavity of said fluid passageway, said ball-poppet guide having a central guide bore extending axially therethrough, said ball-poppet guide having a number of circumferentially spaced-apart axially-extending guide fins protruding radially inwardly into said guide bore, said ball-poppet being received within said guide bore for axial movement within radially inward edges of said guide fins between said open position and said closed position, the inner diameter of said cavity being greater than the outer diameter of said ball-poppet guide in order to allow said ball-poppet guide to float radially within said cavity and to allow said spherical ball-poppet to be substantially self-centering for sealing line-contact with said smaller-diameter end of said frusto-conical valve seat.

20. A pneumatic selector fluid control valve according to claim 19, wherein said frusto-conical valve seat is located within a replaceable valve seat disc removably disposed within said valve fluid passageway.

21. A control valve according to claim 19, wherein said valve mechanism includes a resilient biasing member for resiliently urging said ball-poppet guide toward one axial end of said cavity portion.

22. A control valve according to claim 21, wherein said resilient biasing member is a spring wave washer.

23. A control valve according to claim 19, wherein said high-pressure pneumatic working fluid is at a pressure in the range of 300 psig to 900 psig.

24. A control valve according to claim 23, wherein said high-pressure pneumatic working fluid is at a pressure of approximately 600 psig.

25. A control valve according to claim 19, wherein said low-pressure working fluid is at a pressure irk the range of 10 psig. to 300 psig.

26. A control valve according to claim 25, wherein said low-pressure working fluid is at a pressure of approximately 100 psig.

27. A control valve according to claim 19, wherein said ball-poppet is composed of a metallic material.

28. A control valve according to claim 27, wherein said metallic material includes stainless steel.

29. A control valve according to claim 19, wherein said ball-poppet is composed of a synthetic material.

30. A control valve according to claim 19, wherein said selector fluid control valve supplies at least two different working fluid pressures to a fluid actuated device by way of a separate primary fluid control valve.

31. A control valve according to claim 19, wherein said selector fluid control valve is adapted for supplying more than two different working fluid pressures, further having at least two of said high-pressure inlets in respective fluid communication with at least two sources of pneumatic working fluid at different relatively high pressures, respectively, at least two of said high-pressure ball-poppet valve mechanisms, and at least two of said pilot actuators.

32. A fluid control valve interconnected for supplying at least one working fluid pressure to a fluid-actuated device, said fluid control valve having a body, a flow passage extending through said body, and a generally frusto-conical valve seat in said flow passage, said valve seat having a smaller-diameter end and a larger-diameter end, said frusto-conical valve seat being located within a replaceable valve seat disc removably disposed within said flow passage.

33. A fluid control valve according to claim 32, wherein said valve seat disc is composed of a harder material than that of said body.

34. A control valve for operating a fluid-actuated device. said control valve having an inlet in fluid communication with a source of pressurized working fluid, a load outlet in fluid communication with said fluid-actuated device, a fluid supply passageway providing fluid communication for said working fluid from said inlet to said outlet, said control valve further including a generally frusto-conical supply valve seat located in said fluid supply passageway, said supply valve seat having a smaller-diameter end and a larger-diameter end, and a generally spherical supply poppet being selectively movable between respective supply closed and supply open positions into and out of substantially supply poppet line-contact for sealing with said smaller-diameter end of said supply valve seat, said generally spherical supply poppet having a chord dimension at said line-contact with said smaller-diameter end of said supply valve seat that is smaller than said larger-diameter end of said supply valve seat, said generally frusto-conical supply valve seat having a supply seat angle relative to the centerline of said supply valve seat that is greater than an angle formed by the centerline of said supply valve seat and a line tangent to said spherical supply poppet at said supply poppet line-contact when said supply poppet is in said closed position, any sonic flow erosion caused by said initial working fluid flow as said spherical supply poppet initially moves out of said line-contact to said supply open position and as said working fluid initially flows past said supply poppet being shifted substantially immediately to a flow area adjacent said supply valve seat that is not sealingly contacted by said spherical supply poppet thus substantially minimizing sonic damage to said smaller-diameter end of said supply valve seat.

35. A control valve according to claim 34, further including an exhaust outlet, a fluid exhaust passageway in fluid communication for exhaust fluid between said load outlet and said exhaust outlet, a generally frusto-conical exhaust valve seat located in said fluid exhaust passageway, said exhaust valve seat having a smaller-diameter end and a larger-diameter end, and a generally spherical exhaust poppet being selectively movable between respective exhaust closed and exhaust open positions into and out of substantially exhaust poppet line-contact for sealing with said smaller-diameter and of said exhaust valve seat, said generally spherical exhaust poppet having a chord dimension at said line-contact with said smaller-diameter end that is smaller than said larger-diameter end of said exhaust valve seat, said generally frusto-conical exhaust valve seat having an exhaust seat angle relative to the centerline of said exhaust valve seat that is greater than an angle formed by the centerline of said exhaust valve seat and a line tangent to said spherical exhaust poppet at said exhaust poppet line-contact when said exhaust poppet is in said closed position, any sonic flow erosion caused by an initial exhaust flow as said spherical exhaust poppet initially moves out of said line-contact to said exhaust open position and as said exhaust fluid initially flows past said exhaust poppet being shifted substantially immediately to a flow area adjacent said exhaust valve seat that is not sealingly contacted by said spherical exhaust poppet thus substantially minimizing sonic damage to said smaller-diameter end of said exhaust valve seat.

36. ~A selector fluid control valve for selectively supplying at least two different working fluid pressures to a fluid-actuated device, said selector fluid control valve comprising:
a first-pressure inlet in fluid communication with a source of working fluid at a first pressure;
a second-pressure inlet in fluid communication with a source of working fluid at a second pressure;
an outlet passageway interconnected in fluid communication with the fluid-actuated device, a normally closed first-pressure valve in fluid communication between said first-pressure inlet and said outlet passageway to selectively allow first-pressure fluid flow from said first-pressure inlet to said outlet passageway;
a normally open second-pressure valve mechanism in fluid communication between said second-pressure inlet and said outlet passageway to selectively allow second-pressure fluid flow from said second-pressure inlet to said outlet passageway, a pilot actuator selectively operable to urge said normally closed first-pressure valve mechanism toward an open position and allow said first-pressure fluid flow from said first-pressure inlet to said outlet passageway, said first-pressure fluid in said load fluid outlet passageway urging said normally open second pressure valve mechanism toward a closed position to prevent reverse fluid flow between said first-pressure inlet and said second-pressure inlet.