US3433262A - Bilevel pressure regulating valve - Google Patents

Description

March 18, 1969 W. A. RAY

BILEVEL PRESSURE REGULATING VALVE Filed Nov. 18. 1965 EFFECTNE nm. l- EFFECTIVE manna: l

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wmmm 3,433,262 BILEV'EL PRESSURE REGULATING VALVE William Alton Ray, North Hollywood, Calif., assignor to International Telephone and Telegraph Corporation, New York, N .Y., a corporation of Maryland Continuation-impart of application Ser. No. 284,208, May 29, 1963. This application Nov. 18, 1965, Ser. No. 508,443 U.S. Cl. 137-61419 Int. Cl. F17d 3/00; F16k 31/145, 31/02 This application is a continuation-in-part of my copending application, Ser. No. 284,208, filed May 29, 1963, for Flow Control Means, now abandoned. The benefit of the filing date of said copending application is therefore hereby claimed for this application.

The present invention relates to systems for the control of fluids and has particular utility in gas control systems wherein it is desired to effect a controlled Opening of a main gas valve from a partially open position.

It is desirable in gas heating systems to control the opening of a main valve supplying gas to a main burner such that initially a valve element is moved from its seat relatively rapidly to a partially open position to assure proper ignition of the gas and is thereafter moved from such partially open position to its fully open position at a relatively slow rate to prevent the possibility of what is termed roll back in the system.

The term roll back or roll out has reference to the following. Usually a gas furnace is provided with a flue or chimney which depends upon a heated condition in a fire box for its operation in carrying away gases from the fire box, i.e., upon establishment of proper conditions for a draft through the flue or chimney. When the flue box and connecting flue is cold, as is the condition when the operation of the furnace is initially initiated, proper draft conditions do not prevail, and in such case should the main gas valve in a high heating capacity gas furnace be opened suddenly from its closed position to its fully open position then there exists the possibility that the gases accumulate in the fire box and eventually under the pressure of the gas system emerge or roll out from the fire box into the surrounding area giving rise to an alarming but not necessarily dangerous condition; but, as the fire box becomes heated sufliciently proper draft conditions are established and the gases travel up the flue or chimney as intended.

Thus, in a control as contemplated herein, there is no abrupt opening of a valve from its closed position to its fully open position, but, on the other hand, the valve is initially opened to only a partially open position, and then gradually opened further towards its fully open posisition giving the tire box and flue sufficient time to become heated for establishment of proper draft conditions.

Thus, the control described herein involves a valve element which is moved relatively rapidly from its valve seat to a partially open position to assure proper gas ignition and then moved further towards its fully open position, gradually giving the fire box and flue sufiicient time to become heated for establishment of proper draft conditions thereby preventing the possibility of roll back or roll out.

It is therefore a general object of the present invention to provide improved means and techniques for achieving the above indicated desirable features.

A specific object of the present invention is to provide an improved system of this character, using pressure responsive means in assuring this desired movement of a valve element.

The control system of the invention includes a pressure responsive control valve sequentially movable to low capacity and high capacity flow positions in response to low and high pressures established by a unique pressure reg- 5 Claims United States Patent 0 ulating means. The pressure regulating means employs a regulator valve having a movable valve element connected to a diaphragm with one side of the diaphragm being exposed to the pressure between the regulator valve and the control valve to urge the regulator valve in a closing direction while the other side of the diaphragm forms a wall of a chamber connected through a restricted passage to the outlet side of the control valve to urge the regulator valve in an opening direction. A spring is also provided to urge the regulator valve in an opening direction.

Thus, when the control valve is initially opened, the low pressure on the outlet side of the control valve which exists in the control chamber causes the regulator valve to open partially and establish a low control pressure to open the control valve for initial low capacity flow. As the pressure on the outlet side of the control valve increases and is gradually transmitted to the control chamber, the regulator valve is gradually opened farther, thereby establishing a higher control pressure which gradually opens the control valve to its high capacity flow position.

As another feature of the invention, a second diaphragm is attached to the movable element of the regulator valve and is positioned to form another wall of the control chamber spaced from the first diaphragm. The other side of the second diaphragm is exposed to atmosphere so that proper pressure regulation is obtained. Thus, as the con trol valve outlet pressure approaches the higher control pressure and this higher pressure is transmitted to the control chamber so that as the pressures on each side of the first diaphragm approach equality, the control eflect of the first diaphragm is gradually cancelled and replaced by the second diaphragm. By making the effective area of the second diaphragm less than that of the first diaphragm, a higher control pressure is established by the regulator valve, resulting in the high capacity flow through the control valve.

The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. This invention itself, both as to its organization and manner of operation, together with further objects and advantages thereof, may be best understood by reference to the following description taken in connection with the accompanying drawings, in which:

FIG. 1 illustrates a control embodying features of the present invention for incorporation in a gas heating system, the control being shown partly in section and partly in elevation.

FIG. 2 is a section view taken substantially on line 22 of FIG. 1.

The control having the casing 9 is connected in a gas line between the pressure inlet pipe 10 and outlet pipe 12 extending to a main burner in a heating enclosure, such as a furnace, heater or the like.

The casing 9 is formed with a tapered bore 13 providing a seat for a plug valve element 14 which is manually rotatable in such bore by knob 16 for shutting off all gas flow. Under some conditions mentioned later, the knob 16 may also be used to control the flow of gas to a pilot burner associated with the main burner and may also be used to reset an electromagnetic safety valve having a coil energerizable with current supplied from a thermocouple heated by such pilot burner for safe lighting of the pilot burner. Since such safe light systems are well known in the art, details of the same are not specifically shown and described herein.

Located on the down stream side of shutoff valve 13, 14 is an automatically operated valve 18 which involves a spring urged stem 19 carrying a pair of tapered valve members 21, 22 and centrally mounted on diaphragms 24, 25, the valve elements 21, 22 cooperating respectively with stationary valve seats 26, 27 sealingly mounted in a mating bore 9A in casing 9. The valve seats 26 and 27 are supported by a plurality of integrally formed, depending and outwardly extending legs 28 terminating in an annular flange 29 which is clamped to casing 9. The legs 28 define a plurality of apertures 35, as seen in FIG. 2.

The diaphragm 24 has its peripheral edge clamped between flange 29 and an annular ring-shaped casing member 30 and, in turn, the diaphragm 25 has its peripheral edge clamped between casing member 30 and cup-shaped casing member 32, this clamping being accomplished by using bolts 34 as indicated in FIG. 2, where the casing 9 is provided with a flanged portion 9B.

The stem 19 is provided with a flanged portion 19A and is threaded to receive a clamping nut 19B and between these two elements 19A, 19B, there is clamped an assembly of apertured elements comprising in turn: disc 40, diaphragm 24, and angled skirt member 42, spacer sleeve 43, diaphragm 25, and cup-shaped washer 44.

It will be seen from this construction that there is provided three diaphragm chambers, namely, a first upper diaphragm chamber 23 defined in part by the top side of diaphragm 24, casing member 9, stationary valve seat 27 and its legs 28 and flange 29; a second intermediate diaphragm chamber 31 defined in part by the bottom side of diaphragm 24, the top side of diaphragm 25 and easing member 30 which is apertured to form a part of a passageway 47 leading -from such intermediate chamber to the outlet opening 48 in casing member 9 via the restriction 49 in such passageway; and a third lower diaphragm chamber 33 defined in part by the bottom side of diaphragm 25 and casing member 32 which has a vent hole 32A communicating such lower chamber to the atmosphere. As indicated in FIG. 2 by flow lines, the apertures 35 interconnect chamber 23 with the top of tapered valve members 21 and with annular space or chamber 78 through passage 36 formed in casing 9.

The diaphragm 24 has a larger effective diaphragm area with respect to pressures than does the diaphragm 25 as indicated in FIG. 1 wherein the effective diameters are indicated with respect to the flex circle of the diaphragms, i.e., the diameter at which there is a point of reverse curvature in the diaphragm material.

There is illustrated a diaphragm actuated valve comprising the stationary annular insert valve seat 50 sealingly mounted in casing member 9 and an apertured disc 52 mounted on diaphragm 54 having its marginal edge portion clamped between a casing member 56 and an annular casing member 58 which, in turn, is sealingly secured on the casing member 9.

The casing member 56 is closed at its upper end by its wall portion 56A to thereby provide a diaphragm chamber 62 defined in part by the top side of diaphragm 54.

Within chamber 62 and mounted on wall portion 56A is a three-way solenoid-operated valve 64 having a pair of aligned and spaced stationary ports 66 and 68 between which the flapper valve element 67 is movable to alternatively close either port 66 or port 68 depending upon the energized or nonenergized condtion of a solenoid coil 70 arranged in conventional manner to produce movement of the valve element 67 against port 66 when energized. Normally when the solenoid is deenergized, the valve element 64 closes port 68 which is in communication with passageway 72 that is a venting passageway extending through the wall portion 56A to the atmosphere. The other port 66 is in communication with a passageway 74 in communication with the gas inlet chamber 76 between the stationary valve seats 26 and 27 so that in the condition shown in FIG. 1 there is inlet gas pressure acting on the top side of diaphragm 54 to maintain the main valve 50, 52 closed. This is due to the fact that the gas pressure in chamber 62 acts on a larger projected area portion of the diaphragm 54 than does the gas pressure in the annulyar space 78 surrounding the valve seat 50 in achieving a net valve closing force. This closing force may be supplemented by a coil compression spring 80 having its smaller and retained to engage the shallow cup-shaped member 84 on diaphragm 54 and its larger end retained and bearing on a tongued washer element 86 secured on a mounting bracket 88 for the three-way valve assembly.

The valve stem 19 as seen in FIG. 2 is normally urged upwardly by an adjustably compressed compression spring 90 which has its lower end seated on one end a lever 92 having its other end engaging stem 19 and having an intermediate portion thereof pivoted on a wall portion of housing member 32.

The upper end of spring 90 engages a dished plate which is adjustably positioned by an adjusting bolt or screw 96 threaded in the spring housing member 98 which is also formed to provide a support for the stationary valve elements 26 and 27 and also with an annular bead portion 100 engaged by the disc 40 to provide a stop member for limiting the maximum opening of control valve 21, 26 and control valve 22, 27.

The operation of the system is described under the conditions where the plug valve 13, 14 is open and a pilot burner flame is established adjacent the main burner to which gas may then be fed from the outlet chamber 48 and pipe 12. Under these initial conditions the valve 50, 52 serving as a shut-off valve prevents the flow of gas to the main burner since the full line gas pressure in chamber 76 is communicated through passageway 74 and port 66 to the top side of diaphragm 54 to balance and overcome any pressure existing in chamber 78 acting on the bottom side of diaphragm 54. The valves 21, 26 and 22, 27 are normally almost closed or partially closed by the regulated gas pressure acting on the top side of diaphragm 24 since the regulated gas pressure is normally large enough to essentially overcome the upward force caused by spring 90. Hence, the disc 40 is out of engagement with the top member 100 as seen in FIG. 1. With the valve 13, 14 open and valve 50, 52 closed the valve elements 21 and 22 are in their closest position to their associated valve seats 26, 27 so that valves 22, 27 and 21, 26 are in condition for efiecting maximum gas pressure throttling when valve 50, 52 is opened.

To open the main valve 50, 52 the solenoid 70 is energized to cause the flapper valve element to allow the diaphragm chamber 62 to vent to the atmosphere. It is noted that with valve 50, 52 closed, chamber 48 is at atmospheric pressure as is also the intermediate chamber 31, and chamber 33 is always at substantially atmospheric pressure so that maximum force counteracting the force of spring 90 is present for establishment of this maximum throttling position of valve elements 21 and 22.

When the solenoid 70 is initially energized and chamber 62 is allowed to vent to the atmosphere the valve 50, 52 is slightly opened relatively rapidly due to the pressure in chamber 78. This causes a sudden drop in pressure in chamber 78 which decreases the downward force on diaphragm 24 permitting valves 21, 26 and 22, 27 to open further in response to the urging of spring 90. This, in turn, causes an increase in pressure in chamber 78 with the result that valve 50, 52 initially moves to a partially open position to thus buildup an above atmospheric pressure condition in outlet chamber 48. This initial gas flow through valve 50, 52 and outlet chamber is just adequate to initiate combustion in the main burner.

In accordance with the invention, the pressure in chamber 48 is communicated to the intermediate chamber 31 through passageway 46 where such pressure then acts on both diaphragrns 24 and 25. The flow of gas to outlet chamber 48 is controlled primarily by gas throttling at valves 21, 26 and 22, 27 in effecting a controlled movement of the diaphragm 54 from its initially partially open position to its fully open position. It will be seen that gas throttling by valves 21, 26 and 22, 27 become less the greater the pressure in outlet chamber 48 becomes. This is so since an increase in pressure in the intermediate chamber 31 tends to equalize the force exerted by the throttled gas line pressure on the top side of diaphragm 24 and produces a greater upwardly acting force on the diaphragm 24 than the downwardly acting force on diaphragm 25 which has a smaller efiective area than diaphragm 24. Consequently, an increase in pressure in the intermediate chamber 31 produces a net force acting in the same direction a the force exerted by spring 90 to move the valve elements 21 and 22 further away from valve seats 26 and 27.

As illustrated, the pressure communicated to the intermediate chamber 31 from outlet chamber 48 may be controlled by placing a restricting or metering orifice in passageway 46 for the control of movement of diaphragm 54.

Thus it will be seen that when the valve 50, 52 is opened relatively rapidly, the valves 21, 26 and 22, 27 are in position to limit the movement of valve element 52 to a partially open position which is sufiicient to insure proper gas ignition. Valves 21, 26 and 22, 27 thereafter open further gradually to increase pressure and thus further open valve 50, 52 at a controlled rate to its fully open position to prevent the possibility of roll out or roll back. When valve 50, 52 is in its fully open position, it will be understood that valves 21, 26 and 22, 27 are effectively controlled only by diaphragm 25 and spring 90 and diaphragm 25 serves as the pressure regulating element. I

It will be seen that the flow of gas to the main burner may be interrupted at any time by deenergizing the solenoid 70 to thereby allow the flapper valve element 67 to open port 66 and close port 68 to thereby apply full gas line pressure to the top side of diaphragm 54 and effect closure of main valve 50, 52.

Relatively rapidly closing of the valve 50, 52 takes place since an unthrottled full line gas pressure is used for that purpose which may be supplemented by the provision of spring 80.

It will be appreciated that in its broad aspects the present invention may be practiced in a system where the valve 50, 52 is not necessarily a diaphragm valve. In those cases where the diaphragm valve 50, 52 is used the coil 70 of the three-way valve 64 may be energized as is conventional by a thermocouple heated by a pilot flame and connected in a series circuit with such coil and a temperature responsive switch, i.e., thermostat.

The valve 50, 52 may, for example, be a thermally operated valve instead of a pressure operated valve as found, for example, in space heaters and water heaters in which case it may be desirable to incorporate a conventional safe lighting arrangement as previously indicated, in connection with the description of knob 16.

While particular embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from this invention in its broader aspects and, therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of this invention.

I claim:

1. In a fluid control system:

control valve means in said path normally precluding the passage of fluid therethrough;

valve actuating means for operating said control valve means to partially open and fully open positions responsive to respective first and second pressures on the inlet side of said control valve means to provide low capacity and high capacity fluid flow through said path;

and pressure regulating means for sequentially establishing said fluid first and second pressures, said pressure regulating means including a regulator valve in said path on the inlet side of said control valve means and having a valve seat and a movable valve element which cooperates with said seat, a diaphragm connected to said movable valve element having one side exposed to the pressure between said regulating valve and said control valve means, said diaphragm and said element being arranged such that the pressure between the regulating valve and the control valve means urges said element to close said regulator valve, means defining a control chamber having one wall formed by the other side of said diaphragm, means defining a restricted passageway connecting said chamber to the outlet side of said control valve mean whereby the pressure in said chamber reacting against said diaphragm urges the diaphragm in a direction to open said regulator valve, and a spring connected to urge said regulator valve in an opening direction.

2. The system of claim 1 including a second diaphragm connected to said valve element for controlling the position of said element and having one side forming a wall of said chamber spaced from said first diaphragm with the other side of said second diaphragm being open to atmospheric pressure whereby the pressure in said chamber acting against said second diaphragm urges said regulator valve element in a valve closing direction.

3. The invention of claim 2 wherein the effective area of said first diaphragm is greater than that of said second diaphragm so that when said chamber pressure approaches the pressure between said regulator valve and said control valve means, the forces on said first diaphragm are essentially cancelled and said regulator valve element is positioned by the fluid forces acting on said second diaphragm and by said spring.

4. The invention of claim 1 wherein said control valve means includes a valve seat in said path, a valve member cooperating therewith and a diaphragm carrying said valve member and having one side exposed to the pres sure between said control valve means and said regulator valve.

5. The invention of claim 4 including means connecting the other side of said control valve diaphragm to line pressure in said path on the inlet side of said regulator valve, and means for selectively subjecting said other side of said control valve diaphragm to said line pressure or to atmospheric pressure.

References Cited UNITED STATES PATENTS 1,086,862 2/1914 Schneider l37505.38 X 2,012,162 8/1935 Furlong 137--505.l8 X 2,035,151 3/1936 Eches 137505.38 X 2,957,518 10/1960 Ray 158-129 HAROLD W. WEAKLEY, Primary Examiner.

US. Cl. X.R.

Claims (1)

1. INA FLUID CONTROL SYSTEM: A CONFINED FLUID PATH; CONTROL VALVE MEANS IN SAID PATH NORMALLY PRECLUDING THE PASSAGE OF FLUID THROUGH; VALVE ACTUATING MEANS FOR OPERATING SAID CONTROL VALVE MEANS TO PARTIALY OPEN AND FULLY OPEN POSITIONS RESPONSIVE TO RESPECTIVE FIRST AND SECOND PRESSURE ON THE INLET SIDE OF SAID CONTROL VALVE MEANS TO PROVIDE LOW CAPACITY AND HIGH CAPACITY FLUID FLOW THROUGH SAID PATH; AND PRESSURE REGULATING MEANS FOR SEQUENTIALLY ESTABLISHING SAID FLUID FIRST AND SECOND PRESSURES, SAID PRESSURE REGULATING MEANS INCLUDING A REGULATOR VALVE IN SAID PATH ON THE INLET SIDE OF SAID CONTROL VALVE MEANS AND HAVING A VALVE SEAT AND A MOVABLE VALVE ELEMENT WHICH COOPERATES WITH SAID SEAT, A DIAPHRAGM CONNECTED TO SAID MOVABLE VALVE ELEMENT HAVING ONE SIDE EXPOSED TO THE PRESSURE BETWEEN SAID REGULATING VALVE AND SAID CONTROL VALVE MEANS, SAID DIAPHRAGM AND SAID ELEMENT BEING ARRANGED SUCH THAT THE PRESSURE BETWEEN THE REGULATING VALVE AND THE CONTROL VALVE MEANS URGES SAID ELEMENT TO CLOSE SAID REGULATOR VALVE, MEANS DEFINING A CONTROL CHAMBER HAVING ONE WALL FORMED BY THE OTHER SIDE OF SAID DIAPHRAGM, MEANS DEFINING A RESTRICTED PASSAGEWAY CONNECTING SAID CHAMBER TO THE OUTLET SIDE OF SAID CONTROL VALVE

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