US2865592A - Delayed action valve controlling apparatus - Google Patents

Description

Dec. 23, 1958 G. l. sci-{RANK 2,865,592

J DELAYED ACTION VALVE CONTROLLING APPARATUS Filegl July 2, 1954 2 Sheets-Sheet 1 lNVENTOR Geozye [,Sclraltk BY a W W ATTORNEY Dec. 23, 1958 e. 1. SCHRANK DELAYED ACTION VALVE CONTROLLING APPARATUS Filed July 2, 1954 2 Sheets-Sheet INVENTOR GEOIyeZSC/Wflflk 1. WW CLA ATTORNEY DELAYED ACTION VALVE CONTROLLING APPARATUS George I. Schrank, Teaneck, N. 1., assignor to Specialties Development Corporation, Belleville, N. 3., a corporation of New Jersey Application July 2, 1954, Serial No. 441,021

8 Claims. c1. 251-25 The present invention relates to valve opening apparatus, and, more particularly, to such apparatus wherein carbon dioxide under pressure is utilized to open a valve or operate a piston and such operation is delayed until the carbon dioxide has attained a predetermined pressure.

l-leretofore, many attempts have been made to provide a satisfactory carbon dioxide time delay device, but the trouble with such devices has been that they involved the use of springs, diaphragms or other mechanism which frequently got out of ad ustment, whereby the time during which operation was delayed varied considerably from the tune intended.

Accordingly, an object of the present invention is to provide a time delay apparatus of the foregoing character WhlCll is simple and practical in construction and is accurate and reliable in operation.

Another object is to provide such time delay apparatus which is economical to manufacture and install.

Another object is to provide such time delay apparatus which is particularly adapted for use in connection with pressure operated valves of types now widely used.

'A further object is to provide an improved pressure medium dispensing system wherein such apparatus is utilized.

Other and further objects of the invention will be obvious upon an understanding of the illustrative embodiment about to be described, or will be indicated in the appended claims, and various advantages not referred to herein will occur to one skilled in the art upon employment or the invention in practice.

In accordance with the present invention, the foregoing objects are generally accomplished by metering gaseous and/or liquid carbon dioxide through a given length of tubing having a bore of such diameter that the frictional resistance to the flow of the carbon dioxide therethrough can be utilized to control the time a chamber of a predetermined volume can be filled with gaseous carbon dioxide having sulricient pressure to unseat a spring seated valve or to operate a piston for unseating such a valve.

A preferred embodiment of the invention has been chosen for purposes of illustration and description, and is shown in the accompanying drawings, forming a part of the specification, wherein:

Fig. l is a schematic view of a fluid dispensing system, partly in elevation and partly in section, wherein time delay apparatus in accordance with the present invention is utilized.

Fig. 2 is an enlarged fragmentary view of the time delay apparatus, partly in elevation and partly in section.

Fig. 3 is an enlarged fragmentary view of a modification of the time delay apparatus.

Referring to the drawings in detail and more particularly to Fig. 1, there is shown a system comprising one or more receptacles containing fluid medium under pressure, adapted to be utilized for a desired purpose, and having a fluid pressure operated valve 11 for releasing the medium therefrom into a discharge manifold 12, a

receptacle 14 containing a source of carbon dioxide control head 15 of any conventional type for releasing the carbon dioxide into a conduit or pipe 16, and time delay apparatus 17 having an inlet 19 connected to the pipe 16 and having an outlet 20 connected by a conduit or pipe 21 to the manifold 12.

As shown in Fig. 2, the time delay apparatus generally comprises a container 22, an adaptor body 24 secured to the container, a metering tube 25 supported within the container by the adaptor body, and a fluid pressure operated valve 26 secured to the adaptor body.

The container 22 comprises a body 27 of any desired shape providing a chamber of a predetermined capacity, and a neck or spud 29 formed with a threaded opening 30.

The adaptor body 24 comprises a nipple 31 threadedly secured in the opening 30, a horizontal side bore 32 in fluid flow communication with the inlet 19, a threaded vertical top bore 34 in fluid flow communication with the bore 32, a vertical inlet bore 35 for establishing fluid flow communication between the bore 32 and the container chamber through the tube 25 having a plug 36 secured into the lower end thereof which supports the tube 25, and a side outlet 37 including a vertical bore 39 in fluid flow communication with the container chamber.

In order to prevent foreign matter from entering the tube 25 and blocking or partially blocking the bore thereof to thereby render it ineffective or inaccurate, a filter 38 is positioned in the bore 35.

The valve 26 comprises a nipple 40 threadedly secured in the bore 34 and formed with an inlet 41, the outlet 20, a valve seat 42 between the inlet and outlet, a valve member 44 for the seat, a spring 45 for urging the valve member on its seat, and fluid pressure operated valve mem-- ber unseating means including a cylinder 45 having an inlet 47 connected to the adaptor body outlet 37 by a tube or conduit 49, a piston 50 in the cylinder and a stem 51 carried by the piston for unseating the valve member 44. Preferably, a by-pass passageway 52, controlled by a pilot valve 54 which is adapted to be unseated by a manually operable control head 55, provides fluid flow communication between the valve inlet 41 and the cylinder 46, whereby the valve 26 can be operated at will as described hereinafter.

In accordance with the invention, it has been discovered that stainless steel tubing having a bore of a diameter between about .02 and about .03 inch and having a length at least about times the diameter of its bore is capable of producing frictional resistance of a value to delay the passage of liquid and/or gaseous carbon dioxide therethrough at pressures between about and about 3000 pounds per square inch. For example, it has been found that, when carbon dioxide is metered through such a tube, having a length of between about 2 to about 24 inches, into. a chamber, having a volume of between about 55 and about 215 cubic inches, the time required for the pressure to build up in the chamber to a value of about half that of the pressure in the receptacle 14 and thus effect operation of the piston 50 varies between about 20 and about 40 seconds. Operation of the piston at such pressures is made possible by dimensioning the area of the piston and the effective area of the valve seat 42 and selecting a spring 45 having a given force so that the force tending to move the piston to unseat the valve member 44 is about twice that of the force tending to hold the valve member on its seat.

The diameter of the bore of the tube 25 is believed to be extremely critical. It has been found that a tube of smaller diameter than .02 inch is likely to be clogged due to freezing of the carbon dioxide, and that a tube of larger diameter than .03 inch is not effective to produce the desired friction effect required to slow down 3 the flow of carbon dioxide. The tube length also is important because it accurately predetermines the delay time in a simple and practical manner. Preferably, the tube has a length of about two inches to give a delay time of no-less than about fifteen seconds. This result cannot be accomplished by a simple metering orifice.

The following table illustrates by way of example the manner in which the delay time, that is, the time interval between the opening of the valve 15 and the unseating of the valve member 4- 2, can be varied from about 20 to 40 seconds, which is the preferred range of delayed operation in most instances, the carbon dioxide temperature in each test being about 75 F. and its pressure being about 925 pounds per square inch at the source.

Table I Chamber Tube Bore Diam- Delay Test; No. Vo1" me, Length, eter, in. Time,

cu. ms. 111$. sees.

Tests Nos. 1 to 4 demonstrate that a change in chamber volume varies the delay time.

Tests Nos. 5 to 7, 8 to 14- and 15 to 18 demonstrate that a change in tube length varies the delay time.

Tests Nos. 19 to 22 demonstrate that a change in tube bore diameter varies the delay time.

It will be apparent that a delay time longer than forty seconds can be provided by using longer tubes and larger chambers than set forth in Table I. For example, a two minute delay time can be provided by using a 192 cubic inch chamber and a 43 inch tube having a 0.27 inch bore.

In the event the receptacle 22 selected is so dimensioned that its length is less than the desired tube length, the tube 25 may be bent upwardly at a large radius, as shown, or may be in the form of a coil, and will still function like a straight length of tubing.

The following table illustrates the manner in which the delay time is varied by the temperature and pressure of the carbon dioxide at its source, the chamber volume being 96 cubic inches, the tube being 18 inches and the bore diameter being .027 inch in each test.

These tests demonstrate that the delay time is only varied six seconds between temperature extremes of 120 degrees F. A delay of 38 seconds is not too long while a delay of 32 is not too short. In either instance, should the time delay apparatus be used in connection with a carbon dioxide fire extinguishing system for flooding a space or enclosure, any persons in the space have ample time to escape without too long a delay before the carbon dioxide is released to put out a fire.

The following table illustrates the effect of below freezing temperature on the time delay apparatus, the apparatus being the same as described in connection with Table II.

Table III 002 Tcm- C02 Pres- Delay Test No. perat "re, sire, p. s. i. Time,

1*. sccs.

While this delay time is still tolerable, it can be somewhat shortened by using a charge of carbon dioxide in accordance with the charges described in U. S. Patent Other tests have shown that variations in delay time, due to temperature extremes, can be minimized by the use of a shorter tube than that used with the apparatus referred to in connection with Tables II and III. For example, a five inch tube having a .027 inch bore diameter provides a delay of about 32.5 seconds at 40 F. and a delay of about 22 seconds at F. when used in connection with a 96 cubic inch chamber. Such an arrangement has little delay time variation between about 75 and F.

In Fig. 3, apparatus is shown which is adapted for minimizing variations in delay time due to temperature extremes. This apparatus is essentially like that of Fig. 2, like reference numerals being applied to like parts thereof, but differs in that a second metering tube is provided which is operative at low carbon dioxide temperature and pressure conditions.

In order to accomplish this, the adaptor body has a second vertical inlet bore 35a for establishing fluid flow communication between the bore 32 and the container chamber through a tube 25a supported by a plug 36a. The plug has a bore including a lower section in which the tube 25a is secured, an upper section formed with a valve seat 60 for a valve member or ball check 61 and an intermediate section for a spring 62 normally adapted to keep the ball off its seat.

The spring preferably is constructed and arranged to permit the ball to seat and close the plug bore when the inlet pressure of the carbon dioxide exceeds about 500 pounds per square inch. At such pressures the tube 25 is adequate to effect the desired time delay. However, at lower pressures the ball remains unseated whereby carbon dioxide flows through the plug bore and the tube 251: and assists pressurizing of the container chamber to shorten the time normally taken at low pressures. For example, the bore and length of the tube 25a may be such that it cooperates with the tube 25 to effect a time delay at about 36 seconds at 40 F.

The tube 25a need not necessarily restrict the flow of carbon dioxide due to friction and is more or less a partial by-pass device. However, this tube has a bore and length which prevent freeze-ups therein.

In operation, when utilizing the time delay apparatus of either Fig. 2 or 3, the valve 15 is opened thereby allowing carbon dioxide to enter the container chamber and build up a pressure sufficient to operate the piston 50 within a predetermined time, whereupon the valve member 44 is unseated and carbon dioxide is conducted to the valves 11 to pressure operate the same and release the contents of the receptacles 10 into the manifold 12. If at any time, after the valve 15 has been opened, it is desired to effect such pressure operation immediately without waiting for the piston 50 to be operated by gas from the container 22, the manual control head 55 can be operated to unseat the pilot valve 54 and by-pass pressure medium from the valve inlet 41 to the cylinder 46 and thereby cause the valve member 44 to be unseated.

From the foregoing description, it will be seen, that the present invention provides simple, practical, inexpensive and reliable time delay apparatus which functions within a narrow time interval range over a wide range of carbon dioxide temperatures and pressures, without any adjustment.

As various changes may be made in the form, construction and arrangement of the parts herein, without departing from the spirit and scope of the invention and without sacrificing any of its advantages, it is to be understood that all matter herein is to be interpreted as illustrative and not in any limiting sense.

I claim:

1. Apparatus for accumulating a predetermined volume of gaseous carbon dioxide at a desired pressure within a predetermined-interval of time and then releasing the same, said apparatus comprising a chamber having a predetermined volume, a carbon dioxide inlet, and an outlet means for normally closing said outlet operable by pressure within said chamber to unclose said outlet; and a metering tube connected in fluid flow communication with said inlet and communicating with said chamber for introducing carbon dioxide therein at a predetermined rate, said tube having a through bore of a diameter of between about .02 and about .03 inch and having a length at least about 100 times the diameter of its bore.

2. Apparatus according to claim 1, wherein the volume of said chamber is between about 55 and about 215 cubic inches, the length of said tube is from about 2 to about 45 inches, and the time interval is from about 20 seconds to about 2 minutes when the carbon dioxide temperature at its source is between about 20 and 160 F.

3. Apparatus according to claim 1, wherein the volume of said chamber is about 96 cubic inches, the length of said tube is about 5 inches, the bore diameter is about .027 inch and the time interval is between about 32.5 and not less than about 22 seconds when the carbon dioxide temperature at its source is from about 40 to about 120 F.

4. Apparatus according to claim 1, wherein a second metering tube is connected in fluid flow communication with said inlet and extends into said chamber for introducing fluid carbon dioxide therein, and valve means are operatively connected between said inlet and said second tube, and a resilient means urges said valve means to open position and is adapted to be rendered ineffective to enable said valve means to be moved to closed position and prevent the flow of carbon dioxide therethrough when the pressure of the carbon dioxide exceeds a predetermined value.

5. Apparatus according to claim 4, wherein said sec- 0nd tube is shorter than said other tube and has a through bore of a diameter so dimensioned relative to the dimensions of said other tube that the two tube bores cooperate to introduce low pressure carbon dioxide into said chamber at substantially the same rate as said first mentioned tube alone is adapted to introduce carbon dioxide having a predetermined higher pressure.

6. Valve controlling apparatus responsive to the accumulation of a predetermined volume of gaseous carbon dioxide at a desired pressure within a predetermined interval of time, said apparatus comprising conduit means for conducting carbon dioxide therethrough; a valve in said conduit means-including means for normally urging said valve to closed position; fluid pressure operated means for opening said valve including a cylinder and a valve engaging piston in said cylinder; a container having a chamber of a predetermined volume, an inlet in fluid flow communication with said conduit means and an outlet in fluid flow communication with said cylinder; and a metering tube connected in fluid flow communication with said inlet and extending into said chamber for introducing gaseous carbon dioxide therein at a predetermined rate, said tube having a through bore of a diameter of between .02 and .03 inch and having a length at least about times the diameter of its bore.

7. Apparatus according to claim 6, wherein said valve and said means for urging said valve to closed position include a valve seat, a valve member and a spring, whereby upon introducing a predetermined quantity of carbon dioxide into said chamber to establish a desired pressure therein the pressure of the -carbon dioxide acting on said piston is adapted to overcome the seating force of said spring and effect unseating of said valve member to permit the flow of carbon dioxide through said conduit means.

8. Apparatus according to claim 6, wherein passageway means provide fluid flow communication between said conduit means upstream of said valve and said cylinder, a valve is provided in said passageway means for controlling the flow of carbon dioxide therethrough and being normally urged to closed position by pressure in said conduit means, and manually operable means are provided for opening said last mentioned valve.

References Cited in the file of this patent UNITED STATES PATENTS 1,151,262 Gleeson Aug. 24, 1915 1,825,215 Thomson Sept. 29, 1931 1,919,500 Carpenter July 25, 1933 2,183,346 Buchanan Dec. 12, 1939 2,537,009 Allen Jan. 9, 1951 2,663,153 Grant Dec. 22, 1953 2,670,760 Erikson Mar. 2, 1954 2,780,242 Dyson Feb. 5, 1957

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