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Publication numberUS2132132 A
Publication typeGrant
Publication dateOct 4, 1938
Filing dateMay 14, 1937
Priority dateAug 9, 1935
Publication numberUS 2132132 A, US 2132132A, US-A-2132132, US2132132 A, US2132132A
InventorsSeat Jay Lawrence
Original AssigneeSeat Jay Lawrence
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Fire extinguisher system
US 2132132 A
Abstract  available in
Images(3)
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Claims  available in
Description  (OCR text may contain errors)

J. 1... SEAT FIRE EXTINGUISHER SYSTEM Filed May 14, 1937 3 Sheets-Sheet 1 TTIT I N VENTOR. (51:34 7

BY Y dz ATTORNEKS.

Oct. 4, 1938. J. L. SEAT FIRE EXTINGUISHER SYSTEM 3 Sheets-Sheet 2 I N VE N TOR. W/Ff/VCZ J54 7.

AYZA

Filed May 14, 193'? F ATTORNEYS,

Oct. 4, 1938. .J. L. SEAT FIRE EXTINGUISHER SYSTEM Filed May 14, 1957 3 Sheets-Sheet 3 w 7 $1.11: w in" v V t V g Q o 1 5 A? a w I l.

ATTORNEYS Patented Oct. 4, 1938 PATENT OFFICE FIRE EXTINGUISHER SYSTEM Jay Lawrence Seat, Fair-field, Conn.

Application May 14, 1937, Serial No. 142,548- In Great Britain August 9, 1935 5 Claims.

This invention relates to fire extinguishing systems of the storage tank, pipe line and thermal valve type and more particularly to means for automatically maintaining the pressure in such systems within predetermined limits.

The operation of systems of this type depend on the automatic release of the thermal valves when the temperature in the vicinity thereof increases to a predetermined degree. When a valve opens the fire extinguishing fluid, which is normally maintained in the tank and pipe lines under pressure, is released. As the fire extinguishing fluid is released, the pressure in the system decreases rapidly and unless some means are provided for maintaining the pressure within predetermined limits, the efliciency of the system is seriously impaired. At present it is customary to maintain the pressure in the system by means of an air compressor which is adapted and arranged to automatically start and stop as the pressure in the system varies between predetermined limits. This arrangement is unsatisfactory, however, since it is limited to localities wherein suitable power is available for driving the compressor. Also it frequently happens that during a fire the power is interrupted, thereby rendering the compressor useless. Furthermore, due to the cost of the compressor, it is common practice when designing such systems to take advantage of the fact that only a comparatively few valves are released during a fire, consequently in the event that a comparatively large number of valves are released the compressor is unable to maintain the pressure in the system at desired values.

An object, therefore, of the present invention is to provide means for automatically maintaining the pressure in such fire extinguishing systems within predetermined limits.

Another object of the invention is to provide power operated means for maintaining the pressure in such systems within predetermined values and means independent of the power operated means which operates automatically to supply pressure to the system in the event of failure of the power operated means or in the event the output capacity of the power operated means is insufllcient to maintain the pressure within pre determined values.

Still another object of the invention is to provide means for automatically establishing and disestablishing communication between the storage' tank of such systems and an auxiliary source of pressure as the pressure in the storage tank varies between predetermined values.

In accordance with the invention, the pressure in the system is maintained between predetermined values by power operated means such as an air compressor and an auxiliary source of pressure such as an auxiliary pressure tank wherein air or gas is stored under high pressure. The air compressor is automatically operated by a pressure controlled switch and is designed to maintain the pressure in the storage tank within predetermined values in the event that only a comparatively few thermal valves are released at any one time. The auxiliary tank is connected to the storage tank of the system by means of a pressure operated valve and supplied pressure to the storage tank in the event of failure of the compressor or in the event that a comparatively large number of thermal valves are released and the compressor is unable to maintain the pressure in the system within predetermined values. When the pressure in the system decreases to a predetermined value, the pressure controlled switch closes thereby automatically starting the compressor. In the event or failure of the compressor or in the event the pressure in the storage tank decreases faster than pressure is being supplied by the compressor and the pressure in the system decreases to a further predetermined value, the pressure operated valve automatically opens to establish communication between the auxiliary pressure tank and the storage tank of the-system. This embodiment of the invention is particularly adaptable for localities where power is available to drive the compressor.

Another feature of the invention resides in a gravity fiow valve arranged in the supply line of the system for operating an alarm and setting a fire station indicator means for selective operation when any one of the thermal valves operate in order to audibly sound an alarm and indicate the location of the operating thermal valve.

A still further feature is the provision of a novel strainer arranged in the compressor line to the storage tank to trap moisture of condensation and prevent such moisture from reaching the storage tank.

With these and other objects in view, the invention resides in the certain novel construction, combination and arrangement of parts, the essential features of which will be hereinafter fully described, are particularly pointed out in the appended claims and are illustrated in the accompanying drawings, in which:

Figure 1 is an elevational view, partly in section of my improved fire extinguisher system.

Figure 2 is a vertical transverse sectional View on the line 22 of Figure 1.

Figure 3 is an enlarged vertical sectional View of the valve structure shown in Figure 2.

Figure 4 is a collective perspective view of the valve member and its seal shown in Figure 3.

Figure 5 is a vertical transverse sectional view through the compressed air filter.

Figure 6 is a vertical sectional view on the line E--& of Figure 5.

Figure '7 is a horizontal sectional view on the line l'i of Figure 6.

Figure 8 is an enlarged sectional elevational View of the gravity flow valve with the side cover plate removed.

Figure 9 is a vertical transverse sectional view on the line 9-9 of Figure 8.

Figure 10 is a horizontal sectional view on the line iii-ii! of Figure 8.

Figure 11 is a detail horizontal sectional view on the line H li of Figure 8.

Figure 12 is a diagrammatic view of the electric signalling circuits. 7

Figure 13 is a side elevational View of a modified form of emergency valve.

Figure 14 is a sectional elevational viewlooking at right angle to Figure 13.

' As shown, a storage tank it is partially filled with a suitable fire extinguishing chemical fluid 5 I such as carbon tetrachloride. A charging port 52 is provided in the top of the tank is for introducing the fire extinguishing fluid therein. Normally the charging port i2 is closed and rendered air-tight by a plug 53 which is in threaded engagement therewith. A discharge pipe M. opens from the bottom of tank l8 and extends upwardly through the structure to be protected and in which a manual control valve 96 is conveniently arranged. The control valve 96 is normally open to supply fluid through the supply line during operation of the system. A plurality of branch pipes l5 open from the discharge pipe ll and lead to various sections or compartments of the structure. A plurality. of normally closed thermal valves it open from the branch pipes l5. The thermal valves 96 may be of any of the well known types, the essential feature being that they automatically release when the temperature .in the vicinity thereof increases to a predetermined value. The upper section ll of the tank to is filled with air or gas under a predetermined pressure. Under such conditionsfireextinguishing fiuid is maintained under pressure in the discharge pipe M, the branch pipes i5-and the thermal valves it.

A compressor is for supplying air under pressure to the storage tank IU ofthe system is mounted on the top of the tank H3. Communication between the compressor 58 and the up per section ll of the tank it is established by a pipe 59. A pressure gage 28 is connected to the top of the tank it to giveavisible indication of the pressure supplied by the compressor IS. The compressor E8 is driven by an electric motor 22 which is connected thereto by an endless belt or chain 23. A pressure operated switch 24 is mounted on the top of the tank M3 for automatically starting and stopping the motor 22 which drives the compressor is as the pressure in the tank iii varies between predetermined limits. Communication between the tank ill and the pressure operated switch. 2A is established by a pipe 25. Insulated conductors 2B and 21 lead from any suitable source of current to opposite sides of the switch 24 and similar insulated conductors Z8 and 29 establish a circuit from the switch 24 through the motor 22. When the pressure in the tank l8 decreases to a predetermined limit, the switch 24 automatically closes, thereby starting the motor 22 which drives the compressor l 8 and as a result air under pressure is forced through pipe 89 into the upper section ll of the storage tank 50. When the pressure in the tank I 8 increases to a predetermined value, the switch 24 automatically opens, thereby stopping the motor 22.

Arranged in the pipe is is a filter or separator 38 which includes a casing 3i having-an inlet 32 at one end and an outlet 33 at the opposite end. The inlet and outlet ends of the casing terminate in threaded nipples to which pipe sections of the pipe line I!) connect. A concavo-convex perforated partition 34 is supported by opposite ends of the casing 39 and divides the interior of the casing into an upper filter chamber 35 and a lower moisture accumulator chamber 36. One side of the casing is closed by a removable plate 31 to facilitate access to the inside of the casing. Brass wool 38 is packed in the upper chamber 35 and is prevented from being forced by pressure through the outlet 33 by aperforated guard plate 39 which extends transversely of the upper portion of the casing adjacent the outlet 33. A pet cock 65 is provided in one of the end walls of the casing at the bottom thereof to facilitate the draining off of any moisture which may accumulate therein. The compressed air produced by the compressor l8 must pass from the inlet .32 of the filter casing through the brass wool 38 to the outlet 33 and any moisture present in the air will drop through the perforated partition 34 to the accumulating chamber 35 when it becomes trapped. This prevents the mixing of moisture with the chemical fluid H with which the tank 10 is charged.

Auxiliary pressure tanks to are mounted on cradle supports 4! and 42 which are supported by the storage tank Ill. The auxiliary tanks 40 are filled with air or gas under relativelyhigh pressure. The mouth end of each tank to is provided with a manual control valve '43 from which coupling pipes 44 extend to a common coupling member 45 having radially extending unions 46 for effecting connection of the pipes. Rising from the body of the coupling member 45 is an outlet supply pipe' i'i in which a manual cutoff valve 38 is arranged. A pressure controlled indicator i9 is arranged adjacent but beyond the cutofi valve 48 to give visible indication of the pressure in the auxiliary pressure line when the valves 53 and 68 are open. Communication is automatically established and disestablished between the auxiliary tanks ii] and storage tank Ill by means of a pressure controlled emergency valve 50 as the pressure in the tank l varies between predetermined lower limits. As shown more clearly in Figures 2, and 3, the pressure controlled valve Sil is arranged in a pipe line or conduit a, a portion of which is U-shape. The upper end of the conduit 5! opens into the cut ofi valve 58 and is connected thereto by means of a union 52. The lower end of the conduit 5| opens into the upper section i! of the'storage tank H3 and is in threaded engagement with the inner surface of a bushing 53, the outer surface of which is in threaded engagement with the .shell of the tank iii. A valve supporting bushing 54 is in threaded engagement with the outer surface of the conduit 5!, in one of the legs of the U-shaped section. The uppr r face of the bushring 54 is recessed to receive a beveled washer 55 which provides a seat for a beveled valve member 56. The valve member 56 is connected to the upper end of a valve stem 51. The valve stem 51 is slidably mounted in the bore 58 provided in the bushing 54 and is provided with longitudinal grooves 58' which extendfrom the lower end of the stem to the reduced neck 59 adjacent the head of the valve member 56. The removable valve seat member 55 is held in the recess by a ring-like screw cap 60 threaded to the upper portion of the bushing 54.

. Threaded to the bushing 54 and enclosing the cap 66 is a bonnet or housing 6| having a central bore 62, the top end of which threadedly connects with a section of the pipe line 5|. The bore 62 is in axial alinement with the valve member 56 and threaded therein and terminating directly above and in spaced relation to the normal position of the valve member is a sleeve 63. The lower end of the sleeve is exposed and its sides have spaced openings 64 therein for the passage of gas through the, control valve when the valve member 56 is in a raised open position. The pressure from the tanks 49 opens the valve member 56 when the pressure in the supply tank drops below a predetermined degree, causing the valve member :to rise upwardly and abut the lower end of the sleeve 63, the gas passing through the grooves 58', into the bonnet 6|, through the openings 64 and out through the sleeve 63 to the tank I0 through a section of the pipe line 5|. The valve member 56 closes by gravity when the pressure through the pipe line 5| is shut off by the valve 48, or when the pressure in the tank I8 rises to the desired operating pressure and which backs up through the pipe line 5| against the top of the valve member 56.

Arranged in each branch supply pipe l5 leading from the main supply pipe I4 is a flow alarm device 66 and which is operable to an open position when any one of the sprinkler heads I6 served by a branch line l5 opens by reason of the rupturing of the thermal fuse element of such sprinkler head.

The flow alarm device 66 includes a casting 68 open at one side and which open side is closed and sealed by a removable cover plate 69 secured to the casing by bolts 10. One end of the casing 68 is provided with an inlet nipple 1| and the opposite end wall with an outlet nipple 12. The nipples 1| and 12 are joined by sections of the branch pipe lines I5. The bottom wall of the casing adjacent the inlet extends downwardly at an angle as at 13 while extending from the adjacent end wall above the inlet end disposed parallel to the inclined wall 13 is a partition wall 14. The walls 13 and 14 and the side walls of the casing define a downwardly extending passage 15 through which fiuid entering the casing must pass. Pivoted adjacent the top of the casing 68 as at 16 and insulated therefrom is a contact barrier 11, normally held against the inner end of the partition 14 by a spring 18. One end of the spring 18 is connected to the barrier 11 and the other end to the inlet end of the casing thus holding the barrier in a closing position at the inner end of the passage 15.

Fitted into the end wall of the casing having the outlet, is a bushing of insulating material 19 and slidably supported by the bushing is a contact screw 88, the inner end of which is disposed in the path of the open movement of the barrier 11. The extreme inner end of the screw is provided with a German silver point 8| which is engaged by a similar point 82 carried by the barrier 11. The screw is adjustable relative to the barrier and held in adjusted position by lock nuts 83 which abut opposite ends of the bushing. The screw is adjusted to enable the barrier to move to an open position thereagainst to make contact and yet permit of the free flow of extinguishing fluid through the casing. The

fiow alarm constitutes a switch for operating an audible signal and fire station indicating device which will now be described and as shown in Figure 12 of the drawings.

In Figure 12 the casing 68 is connected to a wire arranged in a relay operating circuit 84, the other end of the circuit extending to the contact screw 80, and interposed in the circuit between the normal break therein caused by the position of the barrier 11 with respect to contact 80, is a transformer 65, pilot light 86, wires 81, leading from a source of electric supply to the transformer, coil 88 of a relay 89, and a station annunciator 90.

Receiving its source of energy direct from the current supply wires 81 is an audible signal circuit 9| which includes a siren 92, pilot light 93 I and relay operated switch 94 normally held open by a spring actuated catch 95.

From the above description, it follows that if the flow'alarm device 68 operates by the blowing off of a sprinkler head in the branch line controlled thereby, that the relay circuit 84 will be closed by reason of the contact of the barrier 11 with the screw 80, causing the coil 88 to be energized, and operation of the annunciator 96 associated with the particular alarm device. energizing of the coil 88 closes the switch 94 against the action of the spring catch 95, which in turn closes the audible signal circuit 9| sounding the siren 92.

By reason'of the sounding of the siren 92, an 1 audible alarm is sounded, and by reference to the annunciator board on which all the annunciatcrs are mounted, the exact location of the fire may be learned.

In order to shut oif the siren 92, the siren circuit 9| must be broken and this may be done by shutting off the flow from the source of supply by the turning ofi of the control valve 96.

To release the catch to effect a resetting of the alarm circuit, I provide a reset circuit 91 which receives its current through the transformer 85 and which also includes a normally open push button switch 98 and an electromagnet 91, the armature of which is disposed adjacent the catch 95 to actuate the same to releasing position against its spring tension. Thus by pushing the reset push button 98, the electromagnet 99 will be energized which draws the catch 95 toward the core of the magnet and away from the lower spring contact of the switch 94 allowing the same to drop to a position against a stop pin I00 and thus causing another break in the siren circuit. The various switches are set for further operation upon the resetting of the other parts of the system.

In the operation of the system herein shown and described, the pressure operated switch 24 is adjusted to close when the pressure in the system decreases to a predetermined value. The force of this pressure backing up into the emergency valve 50 holds the gravity valve member 56 upon the seat 55 against the pressure in the auxiliary pipe line 5| leading to the auxiliary supply tanks 40. The valve member 56 automatically opens under the pressure in the pipe The operated switch 24 is adjusted to close.

line 5| when the pressure in the storage tank l0 :decreases to a lower predetermined limit to establish communication between the auxiliary tanks and storage tank I 0, andcloses upon the building up of pressure in the tank i0 to a value slightly above the pressure at which the pressure Under such conditions when the temperature in the vicinity of a thermal valve l6 increases, to a predetermined degree, the thermal valve automatically opens and fire extinguishing fluid is discharged therefrom under pressure. As the fire extinguishing fluid is discharged the pressure in the storage tank i0 decreases. When the pressure in the tank !0 has decreased to a predetermined value the pressure operated switch 24 automatically closes, thereby starting the compressor I 8, and as a result air under pressure is forced into the tank i0. When the pressure in the tank ID has increased to a predetermined value the pressure operated switch automatically opens, thereby stopping the compressor 18. In the event of failure of the compressor or in the event the pressure in tank l0 decreases more rapidly than it is being supplied by the compressor i8 and the pressure decreases to a further predetermined value, the pressure operated valve automatically opens, thereby establishing communication between theauxiliary pressure tanks 60 and the storage tank iii. In the event the pressure then increases above the value at which the pressure operated switch 24 is adjusted to close, the pressure operated valve 5%! automatically closes, thereby disestablishing communication between the two tanks. Under such conditions the pressure in the storage tank i0 is being maintained by the compressor alone. In the event the pressure continues to increase, the compressor is automatically stopped when the pressure reaches the value at which the pressure operate-d switch is adjusted to open.

A detail description of the alarm signalling system has already been given and a repetition thereof at this point is not deemed necessary, other than to say that upon each operation of a thermal valve 15, the alarm circuit is closed by reason of the flow of fire extinguishing liquid through the flow alarm switch 66.

In Figures 13 and 14 of the drawings, I have illustrated a'modified form of emergency valve designated 'in its entirety by the reference character [0i and which may be substituted for the emergency pressure valve 50 hereinbefore described. The emergency valve lill is in reality an electrically controlled valve and includes a valve casing I02 having a partition I03 therein provided. with a passage H1 3 and with inlet and outlet nipples I05 and E06 respectively to which sections of the pipe 5| are connected. Slidable in the casing I02 is a valve stem I01 carrying a valve head !08 which is urged to closing position by gravity but which valve head is held normally open by an electric solenoid H0. The solenoid H0 is arranged in the current supply circuit of which the wires 26 and 27 form a part and the solenoid is connected to said wires by conductor wires Hi and H2 respectively. The sliding core i i3 of the solenoid is operatively connected with lever means i M which means is also operatively associated with the lower extending end of the valve stem I07. When the solenoid H0 is energized by, reason of the flow of current through the wires 26 and 2? to the motor 22 of the compressor the valve stem i0! is in lowered position with the valve head IUBVseated and closing the passage I04. Should the flow of current through the wires 26 and 27 cease for some unexpected reason, the solenoid becomes deenergized and the spring I09 acting upon the lever means H 1 moves the core inwardly which actuates the valve stem I 07 to move the valve head I08 to unseated open position, thus establishing communication between the auxiliary pressure tanks 30 and the top of the tank l0. By the use of this modified form of emergency valve ifii, it will be appreciated that should the compressor I0 fail to function for the reason that the supply of current thereto is shut off, the auxiliary tanks 30 will supply the tank H) with the necessary pressure. 7

Having thus described the invention, what I claim as new and desire to secure by Letters Patent of the United States, is:-

1. In a fire extinguishing system, the combination with a main storage tank containing. fire extinguishing liquid under compressed air pressure, means for maintaining the air pressure in said tank within predetermined limits, an auxiliary fluid pressure pre-charged storage tank connected to said main storage tank, and automatic valve means acting normally to shut off the fluid pressure from said auxiliary fluid pressure storage tank to said main storage tank and operable to admit fluid pressure from said auxiliary storage'tank to said'main storage tank when the air pressure in said main storage tank dropsbelow predetermined lower limits.

2. In a fire extinguishing system, the combination of a main storage tank containing fire extinguishing liquid under compressed air pressure,

varies between predetermined limits, an inde-i pendent auxiliary pre-charged fluid pressure storage tank, and means for automatically establishing and disestablishing communication between said auxiliary fluid pressure storage tank and said main storage tank only when the air pressure in said latter tank varies between predetermined lower limits.

3. In a fire extinguishing system, the combination with a main storage tank containing fire extinguishing liquid under compressed air pressure, means for maintaining the air pressure in said main storage tank within predetermined limits, an auxiliary pre-charged gas pressure tank, pipe connecting said auxiliary pressure tank and said main storage tank, and automatic valve means in said pipe for automatically establishing and disestablishing communication between said main storage tank and said auxiliary tank as the air pressure in said main storage tank varies between predetermined lower limits.

4. In a fire extinguishing system, the combination with a main storage tank containing fire extinguishing liquid under compressed air pressure, means for maintaining the air pressure in said main storage tank within predetermined limits, an auxiliary pre-charged gas pressure tank, pipe connecting said auxiliary gas pressure tank and said main storage tank, and automatic valve means in said pipe for automatically establishing and disestablishing communication between said storage tank and said auxiliary gas pressure tank as the air pressure in said main storage tank varies between predetermined lower limits, said automatic valve means including a valve seat, and

a valve member held seated against said valve seat by the air pressure from within said main storage tank backing up into said pipe whereby a reduction of air pressure within said storage tank below that of the gas pressure in said auxiliary tank will unseat said valve to admit gas pressure from said auxiliary tank to said main storage tank.

5. In a fire extinguishing system, the combination of a main storage tank containing fire extinguishing liquid under compressed air pressure, an electrically operated air compressor for supplying air under pressure to said tank, an electric current supply for said electrically operated air 15 compressor, a pressure operated switch for auto matically starting and stopping said electrically operated air compressor as the pressure in said storage tank varies between predetermined limits, an independent auxiliary precharged gas pressure tank connected to said main storage tank, valve means for establishing and disestablishing communication between said auxiliary gas pressure tank and said main storage tank, an electromagnetic device energized by said electric current supply to normally hold said valve means closed, and means for opening said valve means upon disengagement of said electro-magnetic device caused by failure of said electric current supply to function.

JAY LAWRENCE SEAT.

Referenced by
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Classifications
U.S. Classification137/209, 200/DIG.300, 340/626, 137/533, 200/DIG.310, 417/44.1, 137/112, 137/565.17, 417/44.2, 169/13
International ClassificationA62C35/60
Cooperative ClassificationY10S200/31, A62C35/605, Y10S200/30
European ClassificationA62C35/60B