JP6491716B2 - Negative pressure wet pre-actuated sprinkler equipment - Google Patents

Description

  The present invention relates to a negative pressure wet pre-actuated sprinkler facility in which secondary side piping is filled with water and is in a negative pressure state except when a fire occurs.

  As a conventional fire extinguishing equipment, when the sprinkler head breaks, etc., it has the function of preventing water leakage and quickly discharging water in the event of a fire. There is a negative pressure wet pre-actuated sprinkler system that is in a negative pressure state.

FIG. 12 is a schematic configuration diagram of such a negative pressure wet pre-actuated sprinkler facility. In the figure, reference numeral 100 denotes a negative pressure wet pre-actuated sprinkler facility.

  Reference numeral 101 denotes a primary side pipe that is piped up from the fire extinguishing water tank 102 via a water pump 103. Reference numeral 104 denotes a secondary side pipe connected to the primary side pipe 101 and piped to the sprinkler head 105.

Reference numeral 106 denotes a pre-operated running water detection device that is installed between the primary side pipe 101 and the secondary side pipe 104 and is kept closed except when a fire occurs. A fire detector 107 is installed on the ceiling and transmits a fire signal upon detecting a fire.

108 is connected to the secondary side pipe 104 at one end side 108A, the other end side 108B is connected to the intake pipe 110 rising from the vacuum pump 109, and a drain pipe 111 having a lower end depending on the fire fighting water tank 102. A suction tube connected to

A flow control valve 112 is installed in the middle portion of the suction pipe 108 so that a small amount of flow is obtained when the negative pressure in the secondary side pipe 104 is normal, and a large amount of flow is provided when abnormal. Further, the flow control valve 112 is an automatic valve with an orifice shown in FIGS. 13 and 14 , and there is a direct-acting electromagnetic valve having a diameter of 40A. And the rating is DC 24 volts, 1,580 mA.

Further, as shown in FIG. 13 , the automatic valve with an orifice, which is the flow control valve 112, is opened from the opening 112a on the inlet side when the negative pressure in the secondary side pipe 104 is normal (slow pressure rise). A small amount of air containing water that has flowed into the body passes through the orifice (small hole) 112A as indicated by an arrow so that the air flows into the opening 112b on the outlet side. Further, when the negative pressure in the secondary side pipe 104 is abnormal (a sudden rise in pressure), as shown in FIG. 14 , the valve body 112e is lifted by the energization via the electromagnetic coil 112c and the plunger 112d to be opened. A large amount flows through the original flow path 112B to the opening 112b on the outlet side.

In FIG. 12 , reference numeral 113 denotes a vacuum switch for detecting the pressure in the secondary side pipe 104 installed at a position on the secondary side pipe 104 side of the flow rate control valve 112 in the middle of the suction pipe 108.

  Reference numeral 114 denotes a signal receiving board that receives a fire signal from the fire detector 107 when a fire occurs and transmits the signal to a control board described later.

  115 receives a signal from the signal receiving board 114, opens the pre-actuated water flow detection device 106 to bring the primary side pipe 101 and the secondary side pipe 104 into communication, and the water pump 103 It is a control panel to be operated. In the other figures, 116 is a steam separator installed at the connection portion of the intake pipe 110 to the suction pipe 108, and 117 is installed at the connection portion of the intake pipe 110 and the drain pipe 111 of the suction pipe 108. Check valve.

  When the fire does not occur, both the primary side pipe 101 and the secondary side pipe 104 are filled with water, and the inside of the secondary side pipe 104 is vacuum pumped via the suction pipe 108 and the intake pipe 110. 109 is a negative pressure state.

Further, when a fire occurs, the fire detector 107 detects a fire and transmits a fire signal to the signal receiving board 114, and transmits the signal from the signal receiving board 114 to the control board 115. Receiving the signal, the control panel 115 opens the pre-actuated water flow detector 106 and activates the water pump 103. As a result, water is continuously discharged from the sprinkler head 105. In this case, the automatic valve with an orifice, which is the flow control valve 112, is in a normal state shown in FIG. 13, and the operation of the vacuum pump 109 is stopped.

The conventional negative pressure wet pre-actuated sprinkler equipment is as described above. However, such equipment has a problem in the configuration that appropriately maintains the state of the negative pressure in the secondary side pipe. This is because an automatic valve with an orifice is used as the flow control valve 112 installed in the middle of the suction pipe 108.

  Thus, such an automatic valve with an orifice is a solenoid valve, and such a solenoid valve has a merit that the control method is simple, such as closing when not energized and opening when energized, while consuming current. It is large and must be energized while the valve element is open, requiring a large power source. As described above, the automatic valve with an orifice used in the conventional equipment is a direct acting solenoid valve having a diameter of 40 A, and its rating is 24 VDC, 1,580 mA, And a large power source was required to open the valve body.

In addition, the electromagnetic valve that has been conventionally used has a problem in the event of a power failure because it consumes a large amount of current as described above and requires a large power source to open the valve element. In other words, during a power outage, the secondary pipe may suddenly increase in pressure due to damage to the secondary pipe, and the valve may need to be opened. It was necessary to take measures such as installing or supplying power with emergency power supply equipment. However, when a storage battery with a large capacity is provided, not only the size of the storage battery itself, but also the size of the control panel for storing it increases, and the cost also increases. In addition, when power is supplied from the emergency power supply facility, it is necessary to estimate the power supply capacity when designing the emergency power supply facility in advance, and there is a problem that the facility cannot be renewed. Further, in the case of an electromagnetic valve, there is also a problem that it cannot be visually confirmed whether the valve is currently open or closed.

The present invention has been made in view of the above, the secondary side as a flow control valve for proper retention of the pressure in the pipe, a large cash strong point power of the conventional orifice with automatic valve-free flow control of the power consumption An object of the present invention is to provide a negative pressure wet pre-actuated sprinkler system which can solve the above-mentioned conventional problems by using a valve.

Thus, the gist of the present invention is that the primary side piping that is piped up from the fire fighting water tank via the water pump,
A secondary side pipe connected to the primary side pipe and piped to the sprinkler head;
A pre-acting flowing water detection device installed between the primary side pipe and the secondary side pipe and maintained in a closed state except when a fire occurs;
A fire detector that detects a fire and sends out a fire signal;
One end side is connected to the secondary side pipe, and the other end side is an intake pipe that is piped up from a vacuum pump, and a suction pipe that is connected to a drain pipe whose lower end is suspended to the fire fighting water tank,
A flow rate control valve installed in the middle of the suction pipe for maintaining the pressure in the secondary side pipe properly;
A vacuum switch for detecting the pressure in the secondary side pipe installed at a position on the secondary side pipe side from the flow rate control valve in the middle of the suction pipe;
A signal receiving board for receiving a fire signal from the fire detector in the event of a fire, and transmitting the signal to a control board described later;
From the control panel that receives the signal from the signal receiving board, opens the pre-actuated running water detection device to bring the primary side pipe and the secondary side pipe into communication, and operates the water pump Become
When the fire is not occurring, both the primary side pipe and the secondary side pipe are filled with water, and the secondary side pipe is filled with the vacuum pump via the suction pipe and the intake pipe. In the negative pressure wet pre-actuated sprinkler equipment to be in a negative pressure state,
As a flow control valve installed in the middle of the suction pipe,
Instead of a solenoid valve,
A main body part through which air and water flowing from the secondary side pipe into the suction pipe pass, a piston part that can be moved forward by the pressure of water in the main body part, and urge the piston part in the backward movement direction A coil spring,
The main body portion includes a cylinder portion and a cover portion attached to one end side of the cylinder portion,
The cylinder part has a cylindrical shape whose one end is closed, and is provided with an outlet at the center of the closed part and an opening having a smaller diameter than the outlet connected to the inside of the outlet.
The cover portion has a cylindrical shape with one end closed, and an inflow port having the same diameter as the outflow port is provided at the center of the closed portion.
The piston part has a cylindrical shape with one end closed, and a flange part having an outer diameter equal to the inner diameter of the cylinder part is formed at the other end, and the opening of the closed part in the cylinder part is formed at the center of the closed part. An opening having a smaller diameter is provided, and an opening having a diameter larger than that of the opening is provided in the cylindrical portion, and the closed portion is moved to the most advanced position against the urging force of the coil spring by the pressure of the flowing water. Is a negative pressure wet pre-actuated sprinkler facility using a flow control valve that does not require power and is in close contact with the inner surface of the closed portion of the cylinder portion.

Further, in the above configuration, the front portion forms a low inclined surface on the outer peripheral portion of the flange portion in the piston portion, while a hole is provided at a position corresponding to the inclined surface of the flange portion of the piston portion in the cylinder portion, In the hole, a columnar indicator whose bottom end is in sliding contact with the inclined surface of the flange portion of the piston portion and is urged to move inward by a coil spring may be removably inserted.

Further, in the above configuration, a hole is provided in the cylinder portion, and a cylindrical indicator urged to move inward by a coil spring is inserted into the hole so that the piston portion can be moved in and out. It may be so arranged that it protrudes from the hole against the urging force of the coil spring by the pressure of the water when it moves up to.

  The present invention is configured as described above, and uses a flow control valve that does not require power as a flow control valve for properly maintaining the pressure in the secondary side pipe, instead of a conventional automatic valve with an orifice that consumes a large amount of power. Therefore, the conventional problems can be solved. Moreover, there is no need to consider power supply from the emergency power supply facility. Further, when the indicator protrudes from the cylinder portion as the piston portion moves to the most advanced position, the position of the piston portion can be visually confirmed.

1 is a schematic configuration diagram of a negative pressure wet pre-actuated sprinkler facility according to an embodiment of the present invention. It is sectional drawing of the flow control valve in the negative-pressure wet pre-action sprinkler equipment which concerns on embodiment of this invention, and shows the state at the normal time. It is sectional drawing of the flow control valve in the negative pressure wet pre-action sprinkler equipment which concerns on embodiment of this invention, and shows the state at the time of fire outbreak. It is. It is sectional drawing of the 1st modification of the flow control valve in the negative-pressure wet pre-actuated sprinkler equipment which concerns on embodiment of this invention, and shows the state of normal. It is an enlarged view of A part in FIG. It is sectional drawing of the 1st modification of the flow control valve in the negative pressure wet pre-actuated sprinkler equipment which concerns on embodiment of this invention, and shows the state at the time of fire outbreak. FIG. 7 is an enlarged view of a portion B in FIG. 6. It is sectional drawing of the 2nd modification of the flow control valve in the negative-pressure wet pre-action sprinkler equipment which concerns on embodiment of this invention, and shows the state of normal. It is an enlarged view of C part in FIG. It is sectional drawing of the 2nd modification of the flow control valve in the negative-pressure wet pre-action sprinkler equipment which concerns on embodiment of this invention, and shows the state at the time of fire outbreak. FIG. 11 is an enlarged view of a portion D in FIG. 10. It is a schematic block diagram of the conventional negative pressure wet pre-operation sprinkler equipment. It is operation | movement explanatory drawing of the automatic valve with an orifice in the conventional negative pressure wet pre-operation sprinkler installation, and shows the state at the time of the pressure rise slowly in secondary side piping. It is operation | movement explanatory drawing of the automatic valve with an orifice in the conventional negative pressure wet pre-operation sprinkler installation, and shows the state at the time of the rapid rise of the pressure in secondary side piping.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic configuration diagram of a negative-pressure wet pre-actuated sprinkler facility 100 ′ according to an embodiment of the present invention. The only difference is the flow control valve installed in the middle of the suction pipe that properly maintains the state of the pressure in the secondary side pipe, and the other configuration is the conventional negative pressure wet pretreatment shown in FIG. Since it is the same as an operation | movement sprinkler installation, the same code | symbol is attached | subjected to the same member and detailed description is abbreviate | omitted.

  Thus, the negative-pressure wet pre-actuated sprinkler facility 100 ′ according to the present embodiment does not require power as a flow control valve for properly maintaining the pressure in the secondary pipe 104 installed in the middle of the suction pipe 108. This flow control valve 1 is different from the conventional negative pressure wet pre-actuated sprinkler equipment 100.

  In addition, as shown in FIG. 2, such a flow control valve 1 that does not require power includes a main body 2 through which air and water flow into the suction pipe 108 from the secondary pipe 104 and water in the main body 2. The piston part 9 is provided so as to be movable forward by pressure, and the coil spring 13 biases the piston part 9 in the backward movement direction.

  The main body 2 includes a cylinder 2A and a cover 2B attached to one end of the cylinder 2A.

The cylinder portion 2A is formed in a cylindrical shape whose one end portion (the right end portion in FIG. 2) is closed, and in the central portion of the closed portion 2A ′, there is an outlet 3 and an inside of the outlet 3. A circular opening 4 having a smaller diameter than the coupled outlet 3 is provided. The outlet 3 is connected to the inflow side of the check valve 117, and the outflow side of the check valve 117 is connected to the joint 108 </ b> B between the suction pipe 108 and the drain pipe 111.

Further, a male screw 5 is engraved on the outer peripheral surface on the other end side of the cylinder portion 2A, and a cover portion 2B in which a female screw 6 is engraved on the inner peripheral surface is screwed and mounted accordingly. Has been made.

The cover portion 2B is formed in a cylindrical shape with one end portion (left end portion in FIG. 2) closed, and an inflow port 7 having the same diameter as the outflow port 3 is formed at the center of the closed portion 2B ′. Is formed.

Further, an O-ring 8 is interposed between the end face on the other end side of the cylinder part 2A and the closed part 2B 'of the cover part 2B, so that water tightness between the cylinder part 2A and the cover part 2B is maintained. I'm leaning.

The piston portion 9 is provided inside the cylinder portion 2A so as to be movable forward by the pressure of water. The piston portion 9 has a cylindrical shape, one end portion (right end portion in FIG. 2) is closed 9 ′, and the other end portion (left end portion in FIG. 2) is formed with a flange portion 10. .

The outer diameter of the flange portion 10 is set substantially equal to the inner diameter of the cylinder portion 2A, and the outer peripheral surface of the flange portion 10 moves along the inner peripheral surface of the cylinder portion 2A. Guides forward and backward movement along the direction.

A circular opening 11 smaller than the opening 4 of the cylinder part 2A is formed in the central part of the closed part 9 'of the piston part 9, and the cylindrical part of the piston part 9 A large-diameter opening 12 is formed.

Further, the piston portion 9 is disposed in the cylinder portion 2A so that the center lines thereof are on the same axis, and the piston portion 9 is movable forward and backward along the center line direction. The piston portion 9 moves to the most advanced position (FIG. 3), so that the closed portion 9 ′ can be brought into close contact with the inner surface of the closed portion 2A ′ of the cylinder portion 2A.

At this time, the opening 4 of the cylinder part 2A and the small-diameter opening 11 of the piston part 9 are superposed with each other. On the other hand, the large-diameter opening 12 formed in the cylindrical portion of the piston portion 9 is blocked by the close contact between the closed portion 9 'of the piston portion 9 and the inner surface of the closed portion 2A' of the cylinder portion 2A. It becomes a state.

That is, when the piston portion 9 is not located at the most advanced position (FIG. 2), the air and water that have flowed into the piston portion 9 are allowed to pass through the small-diameter opening 11 and the large-diameter opening 12. When it is located at the most advanced position (FIG. 3), the water that has flowed into the piston portion 9 can pass only through the small-diameter opening 11 of the piston portion 9.

The total opening area of the small-diameter opening 11 and the large-diameter opening 12 formed in the piston part 9 is set smaller than the opening area of the opening 4 of the cylinder part 2A.

The coil spring 13 abuts on the flange portion 10 of the cylinder portion 2A with the piston portion 9 inserted therein, and presses and urges the piston portion 9 toward the inlet 7 side. Accordingly, the water flows in from the inlet 7 and the piston portion 9 is moved forward in a state where the pressure exceeds the urging force of the coil spring 13.

The elastic force (spring constant) of the coil spring 13 is obtained when water is supplied from the primary side pipe 101 into the secondary side pipe 104 and a part of the water flows into the suction pipe 108 in the event of a fire. It is necessary to reduce the pressure only by the pressure.

Next, the operation of the flow control valve will be described.
  When there is a slow pressure increase due to volume expansion due to temperature change of the secondary side pipe or a small air inflow from the flow rate control pipe, etc. at times other than when a fire occurs, the piston portion 9 moves backward as shown in FIG. The air and water flowing in from the inlet 7 of the cover portion 2B merge through the small-diameter opening 11 and the large-diameter opening 12 of the piston portion 9 and from the opening 4 and the outlet 3 of the cylinder portion 2A. leak.

Further, when the sprinkler head or the like is broken and the pressure in the secondary side pipe rapidly rises, the piston portion 9 is in the same retracted position as in FIG. 2, and the vacuum pump 109 is activated. And this leakage prevents water leakage. At this time, since the suction force of the vacuum pump 109 is lower than the elastic force of the coil spring 13, the piston portion 9 does not move.

Further, when water is supplied from the primary side pipe 101 to the secondary side pipe 104 and a part of the water flows into the suction pipe 108 in the event of a fire, as shown in FIG. The piston portion 9 moves to the most advanced position against the urging force, and the closed portion 9 'is in close contact with the inner surface of the closed portion 2A' of the cylinder portion 2A. At this time, the vacuum pump 109 does not operate. As a result, only a small amount of water flows through the small-diameter opening 11 of the piston portion 9, and sufficient water discharge from the sprinkler head 105 is ensured. Although water continuously flows out from the small-diameter opening 11 of the piston portion 9, the influence of the outflow is small because the diameter of the opening 11 is small.

Then, when the pre-actuated running water detection device 106 is closed after the fire extinguishing is completed, the pressure in the secondary pipe 104 decreases due to water flowing out from the small-diameter opening 11 of the piston portion 9, and the piston portion 9 To return to the retracted position again.

As described above, the flow control valve 1 according to this embodiment operates without requiring electric power.

Next, a first modification of the flow control valve 1 shown in FIGS. 4 to 7 will be described.

The first modified example is configured so that the position of the piston portion can be confirmed from the outside, and other configurations are the same as those of the flow control valve in the above embodiment except for the indicator portion. The same members are denoted by the same reference numerals, and detailed description thereof is omitted.

Thus, in the first modification, an inclined surface 10A having a low front portion is formed on the outer peripheral portion of the flange portion 10 in the piston portion 9, while an inclined surface of the flange portion 10 of the piston portion 9 in the cylinder portion 2A. A hole 2A ″ is provided at a position corresponding to 10A, and a lower end of the hole 2A ″ is in sliding contact with the inclined surface 10A of the flange portion 10 of the piston portion 9 so that the coil spring 14 moves inwardly. A columnar indicator 15 that is urged is inserted in a freely retractable manner. An O-ring 16 is interposed between the indicator 15 and the hole 2A ″ of the cylinder part 2A to maintain the watertightness between the indicator 15 and the cylinder part 2A. Further, the hole of the cylinder part 2A is maintained. An annular spring receiver 17 having a slidably fitted indicator 15 is attached to the opening end of 2A ″.

In the first modified example, as shown in FIGS. 4 and 5, when the piston portion 9 is in the retracted position, the upper end portion of the indicator 15 is immersed in the hole 2A ″ of the cylinder portion 2A. As shown in FIGS. 6 and 7, when the piston portion 9 moves to the most advanced position, the indicator 15 is pushed up by the inclined surface 10A of the flange portion 10 of the piston portion 9, and the upper end portion thereof is the hole 2A ″ of the cylinder portion 2A. It protrudes from.

Next, a second modification of the flow control valve 1 shown in FIGS. 8 to 11 will be described.

The second modified example is configured so that the position of the piston portion can be confirmed from the outside as in the first modified example, and other configurations except for the indicator portion are the flow rate control in the above embodiment. Since it is the same as that of a valve, the same code | symbol is attached | subjected to the same member and detailed description is abbreviate | omitted.

Thus, in the second modified example, a hole 2A ″ is formed through the cylinder portion 2A, and a cylindrical indicator 19 urged to move inward by the coil spring 18 is projected and retracted in the hole 2A ″. It is inserted freely and protrudes from the hole 2A ″ against the urging force of the coil spring 18 by the pressure of water when the piston portion 9 moves to the most advanced position. An O-ring 20 is interposed between 19 and the hole 2A ″ of the cylinder part 2A, and the watertightness between the indicator 19 and the cylinder part 2A is maintained. Further, an annular spring receiver 21 slidably fitted with an indicator 19 is attached to the opening end of the hole 2A ″ of the cylinder portion 2A.

In the second modification, as shown in FIGS. 8 and 9, when the piston portion 9 is in the retracted position, the upper end portion of the indicator 19 is immersed in the hole 2A ″ of the cylinder portion 2A, and As shown in FIGS. 10 and 11, when the piston portion 9 moves to the most advanced position, the indicator 19 is pushed up by the pressure of the water that flows in, and its upper end protrudes from the hole 2A ″ of the cylinder portion 2A. .

1 Flow control valve
2 Body
2A cylinder part
2A 'Blocking part
2A "hole
2B cover part
3 outlet
4 opening
7 Inlet
9 Piston part
9 'Blocking part
10 Flange
10A inclined surface
11 Small diameter opening
12 Large diameter opening
13 Coil spring
14 Coil spring
15 Indicator
18 Coil spring
19 Indicator
100 'negative pressure wet pre-acting sprinkler equipment
100 Negative pressure wet pre-acting sprinkler equipment
101 Primary piping
102 Fire fighting water tank
103 Water pump
104 Secondary piping
105 Sprinkler head
106 Pre-acting water detection device
107 Fire detector
108 Suction tube
109 Vacuum pump
110 Intake pipe
111 Drain pipe
113 Vacuum switch
114 signal receiver
115 Control panel

Claims (3)

A primary pipe that is piped up from the fire extinguishing water tank via a water pump;
A secondary side pipe connected to the primary side pipe and piped to the sprinkler head;
A pre-acting flowing water detection device installed between the primary side pipe and the secondary side pipe and maintained in a closed state except when a fire occurs;
A fire detector that detects a fire and sends out a fire signal;
One end side is connected to the secondary side pipe, and the other end side is a suction pipe connected to an intake pipe that is piped up from a vacuum pump and a lower end that is suspended to the fire-extinguishing water tank, and
A flow rate control valve installed in the middle of the suction pipe for maintaining the pressure in the secondary side pipe properly;
A vacuum switch for detecting the pressure in the secondary side pipe installed at a position on the secondary side pipe side from the flow rate control valve in the middle of the suction pipe;
A signal receiving board for receiving a fire signal from the fire detector in the event of a fire, and transmitting the signal to a control board described later;
From the control panel that receives the signal from the signal receiving board, opens the pre-actuated running water detection device to bring the primary side pipe and the secondary side pipe into communication, and operates the water pump Become
When the fire is not occurring, both the primary side pipe and the secondary side pipe are filled with water, and the secondary side pipe is filled with the vacuum pump via the suction pipe and the intake pipe. In the negative pressure wet pre-actuated sprinkler equipment to be in a negative pressure state,
As a flow control valve installed in the middle of the suction pipe,
Instead of a solenoid valve,
A main body part through which air and water flowing from the secondary side pipe into the suction pipe pass, a piston part that can be moved forward by the pressure of water in the main body part, and urge the piston part in the backward movement direction A coil spring,
The main body portion includes a cylinder portion and a cover portion attached to one end side of the cylinder portion,
The cylinder part has a cylindrical shape whose one end is closed, and is provided with an outlet at the center of the closed part and an opening having a smaller diameter than the outlet connected to the inside of the outlet.
The cover portion has a cylindrical shape with one end closed, and an inflow port having the same diameter as the outflow port is provided at the center of the closed portion.
The piston part has a cylindrical shape with one end closed, and a flange part having an outer diameter equal to the inner diameter of the cylinder part is formed at the other end, and the opening of the closed part in the cylinder part is formed at the center of the closed part. An opening having a smaller diameter is provided, and an opening having a diameter larger than that of the opening is provided in the cylindrical portion, and the closed portion is moved to the most advanced position against the urging force of the coil spring by the pressure of the flowing water. Is a negative pressure wet pre-actuated sprinkler facility using a flow control valve that does not require power and is in close contact with the inner surface of the closed portion of the cylinder portion. On the outer peripheral part of the flange part in the piston part, the front part forms a low inclined surface, while a hole is provided in a position corresponding to the inclined surface of the flange part of the piston part in the cylinder part. 2. A negative pressure wet pre-actuated sprinkler according to claim 1, wherein a cylindrical indicator slidably in contact with the inclined surface of the flange portion of the piston portion and urged to move inward by a coil spring is removably inserted. Facility. A hole is formed in the cylinder portion, and a cylindrical indicator urged to move inward by a coil spring is inserted into the hole so that the piston portion can move up and down, and water when the piston portion moves to the most advanced position. 2. The negative pressure wet pre-actuated sprinkler system according to claim 1, wherein the negative pressure wet pre-actuated sprinkler system protrudes from the hole against the biasing force of the coil spring .

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