US3568775A

US3568775A - Fire protection system with hydraulically timed discharge

Info

Publication number: US3568775A
Authority: US
Inventors: Simon Greenberg; Donald R Tremblay
Original assignee: Gulf and Western Precision Engineering Co
Current assignee: Gulf and Western Precision Engineering Co
Priority date: 1968-11-27
Filing date: 1968-11-27
Publication date: 1971-03-09
Anticipated expiration: 1988-03-09

Abstract

A fire protection system with hydraulically timed discharge includes timing means operated by flow of a predetermined volume of liquid to send a signal for cutting off flow of liquid to the main fire protection system.

Description

United States Patent inventors Simon Greenberg Worcester;

Donald R. Tremblay, Oxford, Mass.

Appl. No. 779,477 Filed Nov. 27, 1968 Patented Mar. 9, 1971 Assignee Gul1'& Western Precision Engineering Company Manchester, Conn.

FIRE PROTECTION SYSTEM WITH HYDRAULICALLY TIMED DISCHARGE 4 Claims, 6 Drawing Figs.

Int. Cl

Field of Search 169/2, 7, 19, 20; 239/71, 74; 137/624] 1, 624.14; 251/25;

References Cited UNITED STATES PATENTS 11/1951 Rider 169/19X 12/1958 Miller 25 l/25X 3/1959 Roberts 169/11 5/1962 Hibbert et a1 137/624.14X 10/1965 Lilly et a1 137/624.14 6/1967 Frick 137/624.14

Primary Examiner-M. Henson Wood, Jr. Assistant Examiner-Michael Y. Mar Attorney-Meyer, Tilberry and Body ABSTRACT: A fire protection system with hydraulically timed discharge includes timing means operated by How of a predetermined volume of liquid to send a signal for cutting off flow of liquid to the main fire protection system.

PATENITEUQAR elsn SHEET 1' BF 2 INVENTOR.

8? ATTORNEYS,

FIRE PROTECTION SYSTEM WITH HYDRAULICALLY TIMED DISCHARGE I BACKGROUND OF THE INVENTION This application pertains to the art of fire protection systems and more particularly to fire protection systems for installation in buildings and including timing means for cutting off the main discharge. The invention is particularly applicable to foam generating type of fire protection systems and will be described with particular reference thereto, although it will be appreciated that the invention has broader application in any system where a hydraulically timed cutoff is desired.

Many buildings are commonly provided with built-in fire prevention systems including pipes and sprinklers running overhead for discharging fire smothering liquid into the building. Certain production facilities and warehouses require a foaming-type fire smothering material due to the nature of material processed or stored in the building. For example, storage of rubber or other similar combustible materials make it desirable to have a foam generating system which will completely fill a room with fire smothering foam within a certain period of time. In many installations of this type the foam generating system is required to completely fill a room with fire smothering foam within a few minutes. Once the room is completely filled with foam it is desired to cut off some of the foam generators so that foam does not run into other areas of the building whereitis not needed and may damage expensive equipment. At the same time, it is desirable to keep some foam generation going to maintain the room filled with foam, because foam dissipates quite rapidly. In conventional systems an electrical timer is used to cut off the main foam generators after a predetermined period of time which corresponds with the time it takes to fill a room with foam. The electrical system is usually one of the first things to go out during a fire and may itself be the cause of the fire. With failure of the electrical system the electrical timer does not cut off the foam discharge devices and excessive foam will be generated. After a relative ly short period of time the foaming solution will be completely dissipated. When this occurs plain water will be discharged through the foam generators to rapidly dissipate the foam in the room and this is very undesirable.

SUMMARY OF THE INVENTION In accordance with the present invention a fire prevention system including foam generators for filling a room with foam in a few minutes includes a hydraulic timing circuit for cutting off the foam generators after a predetermined period of time. The timing circuit is operated by the same hydraulic source that supplies liquid to the foam generators. In one form of the invention an automatic control valve is placed in the line between the main water supply and the foam generators. A secondary line leads from the water supply to a retard chamber through a metering orifice. Water from the main supply fills the chamber through the metering orifice at a predetermined rate. When the chamber is filled a pressure is developed to switch a control valve which then sends a pres-. sure signal to the automatic valve between the water supply and the foam generators to cut off liquid flow to the foam generators. In another aspect of the invention a mechanical timer may be operated by flow of a predetermined volume of liquid past a certain point. The mechanical timer then trips a mechanism to close the valve between the foam generators and the water supply.

It is a principle object of this invention to provide a foam generating fire smothering system with hydraulically operated timing means for cutting off flow of liquid to the foam generators after a predetermined period of time.

It is another object of this invention to provide such a hydraulic timing control which is operated by flow of liquid from the same main water supply which supplies the foam generators.

It is a further object of the invention to provide a hydraulic timing circuit which completely eliminates the need for electrical energy from the main building wiring.

It is another object of this invention to provide a hydraulic timing control which sends pressure signals to an automatic control valve for shutting off the automatic valve after a predetermined period of time.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagrammatic view of a fire prevention system incorporating the hydraulic timing circuit of this invention.

FIG. 2 is a diagrammatic view of a fire prevention system incorporating a modified hydraulic timing circuit in accordance with this invention. I

FIG. 3 is a view of a further form of hydraulic timing circuit in accordance with this invention.

FIG. 4 is a sectional elevational diagrammatic view of'a valve for use with the hydraulic timing circuit of this invention.

FIG. 5 is a sectional elevational diagrammatic view of another valve for use with the hydraulic timing circuit of this invention.

FIG. 6 is a sectional elevational diagrammatic view of another valve for use with the hydraulic timing circuit of this invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT The invention may take physical form in certain parts and arrangement of parts, a preferred embodiment of which will be described in detail in the specification and illustrated in the accompanying drawings.

FIG. 1 shows a foam generating fire prevention system which can be incorporated into a building or the room of a building in a well-known manner. A main valve A is connected with the main water supply of the building. Valve A may be either manually operated or heat sensitive to be actuated by heat from any fire occuring within the building or room .in which valve A is installed. A line 10 leads from valve A to a separating point 12 from which

lines

14 and 16 extend. Line 14 leads to an automatic control valve B which may be a cylinder-operated valve actuated by pressure acting against the cylinder. A line 18 leads from automatic valve B to a separating point 20 from which

lines

22 and 24 extend. Line 22 leads to a tank C containing foam producing solution. A line 26 leads from foam tank C through a metering orifice 28 and check valve 30 to a flow proportioning device 32. Flow proportioning device 32 is also connected with line 24 and may take the form of a venturi for mixing plain water from line 24 with a desirable quantity of water and foam producing solution from line 26. Line 34 leads from flow proportioning device 32 to a plurality of foam generators D which are distributed throughout a building or room. Foam generators D may be of the conventional well-known type including a .screen and fan wherein water mixed with foam producing solution flows from line 34 past screens through which the fans are blowing air to cause the formation of foam. Line 16 leads from separating point 12 to another separating point 36 from which

lines

38 and 40 extend. Line 38 extends to a valve E which is normally open cylinder valve operable to close by pressure acting against a cylinder. Line 42 leads from valve E to separating point 44 from which

lines

46 and 48 extend. Line 48 extends to one end 50 of automatic valve B. Line 46 extends from separating point 44 to a normally closed valve H which may be a cylinder-operated valve operated to open by pressure against a cylinder A. Line 52 leading from valve H is open to atmosphere and defines an exhaust for valve H. Line 40 leads from separating point 36 through a metering orifice 54 to a retard chamber I which is simply a closed container. A line 56 leads from retard chamber J to a separating point 58 from which

lines

60 and 62 extend. Line 60 leads to the other side 64 of valve B to act against the other end of the cylinder within valve B. Line 62 has line 66 leading from it to cylinder end 68 of valve E and line 70 leading to cylinder end 72 of valve H.

In operation of the arrangement of FIG. 1, valve A is opened either manually or automatically when a fire exists within the room or building. Water than flows through line 10, through line 16, through line 38, through normally open valve E, through line 42, and through line 48 to end 50 of automatic valve B. The pressure in line 48 acting against the cylinder at end 50 of valve B shifts the cylinder to open valve B for flow of water through

lines

14 and 18. Water flowing from line 14 through valve B exits through line 18 where it then flows through line 22 to foam tank C. Water pressure forces foam producing solution from foam tank C through line 26, metering orifice 28, and check valve 30 to proportioning flow controller 32. Water also flows from line 18 past separating point 20 and through line 24 to proportioning flow controller 32. The foam producing solution from line 26 is mixed with water from line 24 in proportioning flow controller 32 and exits in line 34 leading to foam generators D. A sufficient number of foam generators D are provided to completely fill the room or building with foam within a calculated time period such as around 4 minutes. Once the building or room is filled with foam it is desirable to cut off foam generation. It may be desirable to cut off the supply of foam producing solution to foam generators D and for this purpose a retard chamber J is provided. Retard chamber J is connected with the main water supply through valve A, line 10, line 16, metering orifice 54 and line 40. The volume capacity of retard chamber J is determined so that it will take a predetermined time such as around 4 minutes to fill it through a constant flow metering orifice 54. Once retard chamber J is filled,

lines

56, 60 and 62 become pressurized. Pressurization of line 62 causes pressure to be exerted through line 66 against the cylinder at end 68 of valve E. This closes valve E so that pressure can no longer be exerted from line 38 through valve E to line 48 against cylinder end 50 of valve B. At the same time, pressure within line 70 leading from line 62 acts against cylinder end 72 of valve H to open valve H. This places line 48 in communication with atmosphere through valve H to exhaust line 52 and relieves the pressure in line 48 so that there is no longer any pressure acting against cylinder end 50 of valve B. Meanwhile, line 60 has become pressurized and creates a pressure acting against cylinder end 64 of valve B to close valve B so that liquid can no longer flow from line 14 through valve B to line 13. This completely cuts off the main supply of liquid for foam generators D and shuts the system down. The system may be reset by closing valve A and draining retard chamber J as through valve 157 to relieve pressure in the lines. This will cause valve E to return to its normally open position and valve H to return to its normally closed position. Valve A can then be reopened to start the whole cycle over again.

It will be noted that the arrangement of FIG. 1 requires two valves in the hydraulic timing circuit H and E. Also, line 60 for exerting a pressure against cylinder end 64 of valve B to close the valve B is at a lower pressure than that from the main supply through valve A due to the presence of metering orifice 54. A manner of using only one valve in place of valves E and H, and also using full line pressure to operate valve B to either open or close is shown in FIG. 2.

In the arrangement of FIG. 2 a valve A leading from the main water supply to the building may again be either manually opened or responsive to heat from a fire within the building. Line 110 leads from valve A to separating point 112 from which

lines

114, 116 and 118 extend. Line 118 leads to foam tank C from which line 120 extends to separating point 122. From separating point 122

lines

124 and 126 extend respectively to flow

proportioning devices

130 and 132 through

metering orifices

134 and 136. Line 114 leads to separating point 140 from which

lines

142 and 144 extend respectively to flow

proportioning devices

132 and 130. Line 146 extends from flow proportioning device 130 to foam generator K. Line 148 extends from flow proportioning device 132 to automatic valve B, from which line 150 extends to foam generators D. From the main water supply through valve A and separating point 112, line 116 leads to separating point 152 from which

lines

154 and 156 extend. Line 154 leads to a four-way cylinder-operated valve M which is operated to change its outlet ports by pressure acting against the end of the cylinder. The cylinder valve M is normally positioned so that water flowing to valve M through line 154 exhausts to line 160 which is connected to cylinder end 162 of valve B. The other cylinder end 164 of valve B is connected with valve M through line 166. An exhaust line 168 from valve M is open to atmosphere and defines an exhaust. Also connected with the main water supply by way of line 156 through metering orifice 170 is retard chamber J. Retard chamber J is connected through line 172 to cylinder end 174 of valve M.

In operation of the embodiment of FIG. 2, water flowing from the main supply through valve A, line 110, line 116, line 154, through valve M and line 160 to cylinder end 162 of valve B causes valve B to open due to pressure exerting against cylinder end 162 from line 160. Water also flows through line 118 to foam tank C and forces foam producing solution through line 120, through line 126 and metering orifice 136 to flow proportioning device 132. Foam liquid is also forced through line 124 and metering orifice 134 to proportioning device 130. Water flowing from the main supply through

lines

114, 142 and 144 to flow proportioning devices and 132 is then mixed with the foam producing solution from

lines

124 and 126 and exits through line 146 to foam generator K, and through line 148, through valve B to line and foam generators D. A sufficient number of foam generators D plus K may be provided to completely fill the building or room with foam in a calculated time period such as around 4 minutes. To completely stop foam generation from the main foam generators D once the building or room is filled with foam retard chamber J is provided. Chamber J is of such a size that the volume of flow through metering orifice 170 will fill chamber J within a calculated time period such as around 4 minutes. Once chamber J is filled line 172 becomes pressurized and pressure is exerted against cylinder end 174 of valve M to shift the cylinder and connect line with exhaust line 168 and inlet line 154 with line 166. By connecting line 160 with exhaust line 168 pressure against cylinder end 162 of valve B is relieved. At the same time, connecting inlet line 154 with line 166 creates a pressure against cylinder end 164 of valve B to close valve B. Water can then no longer flow through valve B to foam generators D. In order to keep the room or building filled with foam once foam generators D are turned off there may be provided a small supplemental foam generator K. Foam generator K is connected with the main water supply through line 144 ahead of valve B so that it continues to operate and receive foam liquid from tank C after valve B is closed. The foam generator K then keeps operating at a slow rate to replace the foam within the room which is naturally dissipated. The system of FIG. 2 may be reset by draining chamber J through valve 157 to relieve pressure in all the lines which will return the system to the original position.

FIG. 3 shows an arrangement for replacing retard chamber J with a volumetric flow measuring device. In this arrangement a line 200 may be connected directly in the line leading from valve A and with discharge line 202 leading either to the foam generators or foam tank C. Line 200 can also be connected in a branch line from the main water supply through valve A and a metering orifice with line 202 simply leading to a waste discharge area. Water flowing through line 200 at a controlled rate drives turbine wheel 204 of turbine drive device P at a constant rate. Turbine wheel 204 is connected with an output shaft 208 connected with a reduction gearing transmission S which has an output shaft 210 on which 220 is secured. Reduction gearing transmission S may be arranged so that cam 220 is rotated one revolution in a predetermined period of time such as around 4 minutes. A manual setting device T for valve M may include a mounting member 222 slidable holding rod 224 which is attached to cylinder 226 of valve M at cylinder end 174. Rod 224 may include a lever 227 adapted to be manually grasped and having laterally extending pin 228 at its other end. A latch member 230 pivoted at 232 is spring biased counterclockwise by spring 234. Latch member 230 may have a notched portion 236 at one end and a roller 238 at its other end. Rod 224 may have a nut or stop 240 fixed thereon at one side of a mounting member 222 to abut against end 239 of mounting member 222. A coil spring 242 on mounting member 222 normally biases rod 224 to the right as shown in FIG. 3. Lever 227 may be grasped in a persons hand to move rod 224 to the left against the force of spring 242. This moves cylinder 226 of valve M to a position in which line 154 is connected with line 160 and line 166 is connected with exhaust line 168. Rod 224 and piston 226 are held in this position by notched portion 236 of latch member 230 engaging pin 228. When valve A is open to supply liquid to main foam generators D, water flowing through

lines

200 and 202 drives turbine wheel 204 to rotate cam 220 at a predetermined rate such as around one revolution every 4 minutes. Cam 220 may be manually set so that cam projection 220 is adjacent roller 238 when the system is initiated. Cam 220 rotates so that the projection 220 must make a complete revolution before coming into contact with roller 238 on its other side. Once cam projection 250 hits roller 238 it causes latch member 230 to pivot clockwise and release pin 228 from notched portion 236. This frees rod 224 for movement to the right under force of spring 242 and shifts cylinder'226 of valve M so that line 154 will be connected with line 166 and line 160 willbe connected with exhaust line 168 as previously described with reference to FIG. 2.

While valves such as B, E, H and M are conventional and well known to those skilled in the art a general and somewhat diagrammatic showing of their manner of operation is given in FIGS. 4-6. FIG. 4 shows valve E including a cylindrical housing 300 closed at end 302 and communicating with water lines 67 at cylinder end 68. A cylinder or piston W is mounted for axial sliding movement within housing 302. Cylinder W includes rather wide reduced

diameter portions

304 and 306 and

ring portions

308, 310 and 312 which are a sliding tight fit within housing 300 and may include gaskets to insure a good sliding seal against the inner walls of housing 300. Cylinder W is normally biased to the right as shown in FIG. 4 by spring 314 acting against cylinder W. Water then flows into housing 300 by means of line 38 and around reduced diameter portion 304 between

rings

308 and 310 to outlet line 42. When pressure is built up in line 66 at cylinder end 68 the water pressure acts against end 316 of cylinder W to shift cylinder W to the left against the force of spring 314. This moves ring 310 to the left side of outlet 42 and closes off communication between inlet 38 and outlet 42. Water pressure acting against end 316 of cylinder W is prevented from exhausting through outlet 42 by ring 312.

FIG. 5 shows the same type of valve only it is normally closed. In this arrangement spring 314 biases cylinder W to the right wherein communication between

line

46 and 52 is prevented by ring 310. Pressure in line 70 at cylinder end 72 of valve H acts against end 316 of cylinder W to shift cylinder W to the left against spring 314 and move ring 310 to the left of exhaust outlet 52. This allows communication between

line

46 and 52 around reduced diameter portion 306 between

rings

310 and 312.

FIG. 6 shows valve M including cylindrical housing 318 having a closed end 319 and a cylinder end 174 communicating with line 172. A piston or cylinder Y is mounted within housing 318 for axial sliding movement. Cylinder Y includes .spaced

ring portions

320, 322, 324, and 326, separating reduced

diameter portions

330, 332 and 334. Spring 340 acting against the inside of end 319 of housing 318 also acts against end 342 of cylinder Y and holds cylinder Y in a leftward position. In this position, inlet 154 communicates around reduced diameter portion 332 between rings 322 and 324 with outlet 160. At the same time, outlet 166 communicates around reduced diameter portion 334 between

rings

324 and 326 with connecting line 344 to exhaust 168. Pressure in line 172 at cylinder end 174 acts against end 346 of cylinder Y to shift cylinder Y to the right against the force of spring 340. Ring 322 then moves to the right of outlet and ring 324 moves to the right of outlet 166. Inlet 154 then communicates with outlet 166 around reduced diameter portion 322 between rings 322 and 324 while exhaust line 344 is separated from outlet 166 by ring 324. At the same time, outlet 160 is connected with exhaust line 168 by connecting line 348 around reduced diameter portion 330 between rings 320 and 322. It will be understood that valve B can be of the same general type as described for valve M only without ring 340 and without

exhaust lines

344 and 348, end 319 of valve M would then have another water connection inlet just as at cylinder end 174 for line 172.

It will be recognized by those skilled in the art that many.

other arrangements could be made such as a float within chamber J mechanically connected with valve M or even directly with valve B. Also, the mechanical arrangement of FIG. 3 could eliminate valve M by connecting directly to valve D and making valve B a normally closed valve which is held open by the mechanical linkage for only a predetermined time such as around 4 minutes until it is closed by cam 220 acting against latch 230. It will also be recognized that an arrangement such as shown in FIG. 3 could be used to bend a piezoelectric crystal by means of projection 250 on cam 220 for sending a voltage signal to an electrically operated valve. It is also possible to have lines such as 160 and 166 in FIG. 2 connected to a separate source of air pressure through valve M rather than with the main water pressure through line 154.

It should be understood that the embodiment of FIG. 2 is a preferred arrangement and the other embodiments have been shown merely to show other obvious but somewhat less desirable systems. It will be recognized that obvious modifications and alterations of the arrangements described will occur to those skilled in the art upon the reading and understanding of the specification.

We claim:

1. A fire protection system including liquid discharge devices connected with a source of liquid under pressure through automatic valve means having open and closed positions, said automatic valve means being pressure-operated to open and pressure-operated to close and having a pressure opening connection and a pressure closing connection, liquid pressure source means connected to said automatic valve means, hydraulically actuated timing means connected with said source of liquid through metering flow means and with said automatic valve means, said hydraulically actuated timing means including control valve means connected between said liquid pressure source means and said automatic valve means, said control valve being operated by a predetermined flow of liquid from said source of liquid under pressure to selectively connect said liquid pressure source means with one of said pressure opening and closing connections on said automatic valve means and to release pressure from the other of said connections.

2. The system of claim 1 wherein said control valve means comprises a single four-way valve.

3. The system of claim 1 wherein said hydraulic timing means comprises a chamber receiving liquid from said source of liquid and said control valve means is pressure operated, said control valve means being connected with said chamber and being responsive to pressure developed by a predetermined fiow of liquid from said source of liquid into said chamber to operate and open said liquid pressure source means to said one connection and release pressure from said other connection.

4. The system of claim 2 wherein said control valve means comprises a single four-way valve and said source of liquid is selectively directly connected to either said pressure closing connection or said pressure opening connection of said automatic valve means through said four-way valve, said four-way valve normally connecting said source of liquid with said pressure opening connection and connecting said source of liquid with said pressure closing connection upon operation of said four-way valve by pressure from said chamber.

Claims

3. The system of claim 1 wherein said hydraulic timing means comprises a chamber receiving liquid from said source of liquid and said control valve means is pressure operated, said control valve means being connected with said chamber and being responsive to pressure developed by a predetermined flow of liquid from said source of liquid into said chamber to operate and open said liquid pressure source means to said one connection and release pressure from said other connection.