US2475489A - Valve for automatic sprinkler systems - Google Patents

Description

July 5, 1949. K B. E. GATHERcoAL S 'VALVE FOR AUTOMATIC SPRINKLER SYSTEMS Filed June 18, 1945 INVENTOR. GAT/,Imaan 'mr EI Patented July 5, 1949 VALVE FOR AUTOMATIC SPRINKLER SYSTEMS Bert E. Gathercoal, River Grove, Ill. Application .lune 18, 1945, Serial No. .600,111 3 Claims. (Cl. 169-20) This invention relates to control valves for automatic sprinkler systems and more particularly to valves for use with dry pipe systems and arranged to admit water into the systems upon opening a sprinkler head, or upon actuation of other heat sensitive means associated with the system.

Dry pipe sprinkler systems are generally considered to be advantageous for providing automatic sprinkler protection in areas subject to freezing temperatures such as cold storage warehouses or in buildings subject to temperatures below freezing, but heretofore the control valves required in such systems have embodied certain undesirable features. For example, the mechanisms employed are rather complicated and expensive and sometimes get out of order. The systems ordinarily require the maintenance of air under fairly high pressure, say about 60 pounds per square inch, in the pipes of the sprinkler systems. The use of air pressure in the systems has resulted in further complications, for it has been necessary to provide so-called quick operating devices, such as exhausters or accelerators, to speed the discharge of water from the open sprinkler heads. Without such devices considerable time would elapse before water could be discharged from the sprinkler heads, because all of the air in the system would .rst have to be exhausted rom the system through the sprinkler heads that have opened.

Accordingly, it is a general object of the present invention to provide an improved type of valve for dry pipe sprinkler systems by use of which the objections ject is the provision of a dry pipe valve which requires only a relatively low pressure of air about 10 pounds per square inch, in the pipes. A further object is the provision of such a valve in which the need for an accelerator valve is eliminated because of the comparatively small amount of air to be bled from the system. Another object is the provision of such a valve which will permit water to flow into the system immediately upon a sudden drop in air pressure in the system such as would be occasioned by the open ing of a sprinkler head, but which will not open the valve to admit water in the event of a slow reduction in pressure such as might occur because of a slow leali in the system or changes in l temperature. Further objects of the invention are the provision of such a valve in which corrosion of the working parts is substantially prevented; the provision of a simple and comparatively inexpensive valve of the character denoted above are eliminated. Another obscribed; the provision of a valve which has failsafe characteristics in that water will be admitted to the system in the event of failure; and the provision of a simple and sturdy valve which can be manufactured at relatively low cost.

Further objects and advantages of my invention will become apparent from the following de scription of a preferred form thereof, reference being made to the accompanying drawings wherein Figure 1 is an elevational view partly in section, somewhat diagrammatically illustrating a valve made according to my invention as it may be incorporated into a sprinkler system; Figure 2 is a fragmentary elevational view as indicated by line 2`2 of Figure 1, illustrating the main water valve itself; Figure 3 is a fragmentary sectional view on an enlarged scale illustrating a portion of the control mechanism; and Figure 4 is an eX- ploded view showing the control valve setting and indicating mechanism removed from the valve assembly and rotated about 45 from the position shown in Figure 1.

The device is illustrated in the drawings as being associated with a special pipe section or valve housing indicated generally at I0 and interposed between the water supply pipe I I and the pipe I2 leading to the sprinkler system itself, one of the sprinkler heads being indicated diagrammatically at i3. Obviously such a system would ordinarily include a considerable number of sprinkler heads I3 connected to pipes branching from the pipe I2. In service, the pipe II contains water under the pressure of the supply mains, while the pipe I2 is normally dry, containing air under pressure of about 10 pounds per square inch, except when a sprinkler head opens in which case water from pipe il is permitted to pass through the housing EEB into the pipe I2.

The flow of water through housing I0 from pipe I I to pipe I2 is controlled by the clapper valve I4 which is provided with a rubber sealing ring I5 adapted to seal against the valve seat I6 formed at the end of the inlet conduit section I'I of the valve housing I0. The valve I4 is retained in closed position against the pressure of water within the section I'I by the plunger I 9, the end of which engages the projecting tongue 20 of the valve clapper I4. As long as the plunger I9 is held downwardly against the tongue 20, the valve clapper is maintained in closed position; if the plunger is permitted to move upwardly, the valve clapper is immediately opened by the pressure of water behind it and takes a position out of the path of the water, as shown in broken lines in Figures 1 and 2. It will be noted that the valve bellows and the chamber 25 being afforded by the very slight clearance space between the rod 42 and the head 51 of the bellows 54 and by the small orifice 65 in the head 51. A spring '55 acting between the partition 52, and the head 62 of the large bellows tends to urge the head of the large bellows to the left in the drawings.

With this arrangement, so long as the pressure within the pipe I2 and chamber I il above the valve I4 remains at the desired level, this pressure acting on the exterior of the larger bellows 53 holds the parts in substantially the position shown in the drawings. Any sudden reduction in pressure, however, will result in an expansion of the larger bellows 53 and the movement of the head '62 thereof to the left in response to the action of the spring 66. The increase in volume within the large bellows will reduce the pressure within both the larger and smaller bellows, and accordingly oil under atmospheric pressure on the exterior of the smaller bellows 54 within the chamber 25 will act to contract the smaller bellows, the orifice 65 and the clearance between the shaft 42 and the head of the smaller bellows being sufficiently restricted that oil cannot flow into the smaller bellows rapidly enough to prevent contraction of the bellows in response to a sudden drop in pressure. Because of the smaller size of bellows 54, the head 51 thereof will tend to move a greater distance in response to changes in pressure than the head 62 of the larger bellows 53. The engagement between the head of the smaller bellows and the shoulder 53 will result in the movement of the rod 42 to the left and rotation of the valve 21 to open position, permitting flow of liquid from the chamber 2S to the chamber 25 and permitting the plunger I9 to move upwardly to release the clapper valve I4 and admit water into the system. This is the sort of action that will take place upon the opening of a sprinkler head, or in response to other heat sensitive means associated with the system, or if for any reason the air pressure within the dry side of the system drops with sucient rapidity the sensitivity of the system can be varied quired to open the valve.

In the event of a slow leak by which the pressure might be reduced gradually over a period of several hours, or if the pressure should change gradually because of changes in temperature, then the larger bellows will expand so slowly that fluid from the chamber 25 can iiow to the interior oi the bellows through the orifice 65 and the slight clearance around the rod 42 fast enough to prevent any substantial contraction of the smaller bellows from taking place. The clearance between the flanges 59 and 6D will prevent the initial movement of the head 52 from actuating the rod 42 to open the valve. However, if the pressure should continue to drop to a predetermined low value, say one or two pounds per square inch, then the larger bellows would be expanded to such an extent by the spring 65 that the inwardly turned flange 60 will engage the end ange 59 of the rod 42 and move it to the left, opening the valve 21 and permitting the clapper valve I4 to open as before. Thus the system normally responds only to rapid pressure drops such as would occur in the event of the opening of a sprinkler head, but ultimately if the pressure reaches a predetermined low value, water will be admitted to the system. It is contemplated that 6 an alarm may be provided which will be set off if the pressure in the system is reduced to a predetermined amount, above the pressure at which the large bellows is set to open the valve, thus giving an indication of slow leak before the system is filled with water.

After the clapper valve has been opened to admit iluid to the system, it may be reset by shutting oi the water in the supply pipe II and draining the system, moving the valve I 4 back onto its seat and positioning the plunger I9 in the tongue 20 thus drawing down spring 38 and permitting oil to now downwardly through valve 21. This may be accomplished through the hand hole 1U (see Figure 2), which is closed by a suitable removable cover plate.

The valve 21 may be opened to admit oil to the chamber 26 by means of the knob 1I which projects to the exterior of the housing 40 and is connected to the key 46 by a sleeve portion 12. The opening in the housing 40 through which sleeve 12 extends is large enough so that the pressure in chamber 25 can always be maintained at atmospheric pressure. By lifting up the knob 1I so that key 46 engages only the collar 49 and not the collar 44, the valve 21 may be turned to admit oil which flows freely from chamber 25 to the chamber 26 and then, after the plunger I9 is properly positioned against tongue 2i), it may be turned manually to closed position, locking plunger I 9 against the tongue 20 to retain the valve I4 in closed position. The water in supply pipe II may then be turned on to make certain there is no leakage past rubber sealing ring I5 and valve seat I'S. The removable cover plate is then secured to hand hole 10 and air under pressure is admitted to the system above clapper I4. By noting whether knob 1I is in a raised position engaging only collar 49 or in a lowered position engaging both collars 44 and 49 it may be determined whether or not the valve is properly set since the position of the mark 13 on the top of the knob 1I when in a lowered position indicates the position of the grooves 4I in valve 21.

From the foregoing it will be evident that my invention provides a system in which the water valve I4 will be operated promptly in the event of any sudden drop in pressure in the dry side of the system, but will not be operated by a slow drop in pressure until a predetermined low pressure is reached. However, regardless of the position of the large bellows 53 when the sudden pressure drop occurs, any sudden drop will result in immediate movement of the head 51 of the smaller bellows to the left which immediately engages the shoulder 58 and moves the rod 42 to open the valve 21. Thus the pressure within the dry side of the system need not be maintained accurately so long as it is above a predetermined minimum. High pressures need not be maintained within the dry side of the system, for the water pressure tending to open the valve i4 carinot react against the mechanism within the Lipper chamber 25. Inasmuch as low pressures may be employed the relatively small amount of air will be exhausted rapidly from the system in the event of opening of a sprinkler head, and therefore, the need for auxiliary accelerating devices is eliminated.

It will be noted that failures of various parts of the apparatus will result in opening the valve I4 and filling the dry side of the system with water; hence the device has fail-safe characteristics. A leakage in the chamber 26 or bellows 21B would permit the plunger I9 to move upwardly, and the valve I4 to open. Failure in the conduit 64 extending from the housing -40 to the housing I0 would result in a reduction in pressure on the exterior of the bellows 53, which would open the valve 21 and therefore open the valve I4. A leak in the bellows 53 would admit air under pressure to the interior of the bellows, equallizing the pressures on the outside and inside of the bellows, and thus permitting the spring lt6 to move the head of the bellows to the left, operating the rod 42 to open the valve 2l. Failure of the bellows 54 might result in slowing down of the operation of the system, but could not otherwise effect it.

While failure of these parts would not be dangerous, nevertheless, the structure is simple and sturdy so that failures are very unlikely to occur. Furthermore, all of the working parts of the apparatus, with the exception of the clapper valve I4 and plunger I9, are immersed in or filled with oil, and thus protected from corrosion.

Those skilled in the art will appreciate that various changes and modifications may be made in the apparatus without departing from the spirit and scope of my invention. Therefore, it is to -be understood that my patent is not to be limited to the preferred form described in detail in this specification or in any manner other than by the scope of the appended claims.

I claim:

1. A valve for a -dry pipe sprinkler system comprising a main clapper valve adapted to control the flow of water into said vdry pipe system, a plunger engaging said .main valve for retaining it in closed position, hydraulic means for holding said plunger in engagement with said main valve, a control valve means, and operating means for said control valve comprising a chamber divided into two portions by a partition, the portion on one side of said partition being subject to the pressure within said dry pipe system, the por-tion on the other side of said partition being subject to atmospheric pressure, a flexible diaphragm mounted on said partition and extending into the said portion subject to pressure within saidv dry pipe system whereby the exterior of said diaphragm is subject .to the pressure within said vdry pipe system, another flexible diaphragm mounted on said partition and extending into the said portion subject to atmospheric pressure whereby the exterior yof ysaid other diaphragm is subject to r atmospheric pressure, the .interiors of said diaphragms being in substantially unrestricted communication with each other and the interior of said diaphragms being in restricted Acommunica- -tion with the portion of said chamber subject to atmospheric pressure, whereby relatively rapid changes in pressure within said dry pipe system will cause movement of both said diaphragms and relatively slow changes `in pressure will cause movement only of the diaphragm subject to pressure within said dry ,pipe system, and means -engageable by said diaphragms 'for operating said control valve to release said plunger and permit said main valve to open in lresponse to a rapid decrease in pressure in sa'id dry pipe system and for controlling `said hydraulic-iz in response to any reduction in pressure in said dry pipe system below a predetermined minimum.

:2. A valve for a dry pipe sprinkler .system comprising a main valve adapted to control the flow of water into said dry pipe system, means for controlling said main valve, comprising two flexible diaphragms, one side of the iirst diaphragm being subject to the pressure of fluid within said dry pipe system and the other side thereof being subject to the pressure of fluid between said diaphragms, one side of the second diaphragm being .subject to the pressure of fluid between said diaphragms and the other side thereof being subject to atmospheric pressure, the space between said diaphragms being in restricted communication with atmospheric pressure, whereby relatively rapid changes in pressure Within said dry pipe system will cause movement of both said diaphragms and relatively slow changes in pressure will cause movement only lof the first diaphragm, and means operated by said second diaphragm for opening said main valve in response to a rapid decrease in pressure in vsaid dry pipe system and voperated by said first diaphragm for opening said main valve in response to a reduction in pressure in said dry pipe .system below a predetermined minimum.

3. A valve for a dry pipe sprinkler system comprising a main clapper lvalve adapted to control the flow :of water into said dry pipe system, a plunger engaging said main valve for retaining it in closed position, hydraulic means for holding said plunger engagement with said main valve, a control valve for .controlling said hydraulic means, and means for opening said control valve to permit said main valve to open, comprising two flexible diaphragms, one side of the rst diaphragm being subject to the pressure of fluid within said dry pipe system and the other side thereof being subject to the pressure `of fluid between said diaphragms, one side of the second diaphragm being subject to the pressure of fluid between said diaphragms and the .other side thereof bei-ng subject to atmospheric pressure, the space between vsaid diaphragms being in restricted communication with atmospheric pressure, whereby relatively rapid changes in pressure within said 'dry pipe system will cause movement vof both said diaphragms and relatively slow changes in pressure will cause movement only of the first diaphragm, and means operated by said second diaphragm for opening said control valve in response to a rapid decrease in pres- .sure in said dry Apipe system `and operated by said first diaphragm for opening `said control valve only in response toa reduction in pressure in rsaid dry pipe .system below a predetermined minimum.

BERT E. GATHERCOAL.

REFERENCES CITED The following references 4:are of record in the file 4of this patent:

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