JPH0440968A - Pressure controller for chemical fire truck and chemical fire truck - Google Patents

Abstract

PURPOSE:To display complete fire extinction performance by always radiating a bubble extinction agent by introducing the entry pressure of a valve to a piston small in diameter, the exit pressure to a piston large in diameter, and the air between both pistons, opening/closing the valve by the balance of the pressure, and adjusting water pressure. CONSTITUTION:A controller 1 is equipped with the valve 2, and the piston 4 small in diameter and the piston 5 large in diameter are provided at the stem 3 of the valve 2. The pressure receiving part 4a of the piston is communicated to an entry 6 with a conduit 8, and the pressure receiving part 5a to an exit 7 with a conduit 9. A cavity 11 between the pistons 4, 5 is communicated to the air at a bleather 12. When the controller 1 is connected to the water source of a fire hydrant T, etc., the pressure at the entry 6 and the exit 7 go to the one almost equivalent to the water pressure of the water source, and the piston 5 large in diameter is moved in a direction to close the valve 2 by pressing the piston 4 small in diameter and a spring 15, and a terminal part 2a closes a side port 10a. When the pressure at the exit 7 is lowered by driving a discharge pump P1, the pressure applied to the piston 5 large in diameter is decreased, and the valve 2 is opened, and the valve 2 is stopped at a prescribed position, and the water absorption part of the discharge pump P1 can be always kept at low pressure, for example, around 0.3-1.5kg/cm, and a mixer M can mix foam liquid.

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to a fire hydrant pressure regulator used in a chemical fire engine;
The present invention also relates to a chemical fire engine that uses this pressure regulator to emit fire extinguishing foam.

(Prior art) A chemical fire engine that emits foam fire extinguishing liquid has a water spray pump and a foam fire extinguishing liquid concentrate pump that are driven by the same engine, and the concentrate pump pumps the concentrate into a foam connected to the discharge side of the water spray pump. The raw solution is mixed into the water stream using a mixer.

In this chemical fire engine, when the water spray pump is connected to a normal water source below the pump position, such as a fire prevention water tank, the mixer mixes the foam stock solution with water at the normal mixing ratio and discharges the foam fire extinguishing solution. In this case, the discharge pressure of the water pump is usually 5 to 15
The mixer maintains the normal mixing ratio even if it is varied up or down to 2 kg/cm. However, beyond this range, it is difficult to obtain a good mixing ratio.

However, when such a chemical fire engine A is used in a petroleum complex etc., not only the normal water source S but also 5 to 14
It is often used by directly connecting to a fire hydrant T that has a water pressure of kg/cm' (see Figure 2).

In such a case, the discharge pressure of the water pump will be higher than the pressure of the fire hydrant, and the mixer will not be able to properly mix the foam concentrate.As a countermeasure, drive the water pump and monitor its discharge pressure, while checking its pressure gauge. The pressure of the fire hydrant is adjusted by adjusting the opening of the fire hydrant valve located far away from the fire hydrant. Such operation is not necessarily the preferred method in a fire emergency.

Therefore, realistically, two fire engines would be connected in series, one would stop the raw solution pump and drive only the water pump to adjust the water discharge pressure, and the other would stop the water pump and drive the raw solution pump to adjust the water discharge pressure. This is an uneconomical firefighting operation in which foam concentrate is mixed into the water stream at the same injection pressure.

(Problems to be Solved by the Invention) In view of the above-mentioned problems, the present invention, when a water pressure fire hydrant is used as a water source, automatically lowers the pressure of the water suction part of the water discharge pump to reduce the discharge pressure of the water discharge pump. The present invention provides a pressure regulator that adjusts the pressure to the applied pressure of a mixer, and a chemical fire engine using this pressure regulator.

Means for Solving the Problems> In other words, the pressure regulator for a chemical fire engine according to (1) of the present invention has a small-diameter piston and a large-diameter piston in the valve stem, and the small-diameter piston has a is a device that controls the inlet pressure of the valve, the large diameter piston controls the outlet pressure, and the atmosphere between both pistons, and opens and closes the valve depending on the balance of pressure applied to both pistons to adjust the water pressure of the fire hydrant. (2) is characterized in that the pressure device of (1) of the invention is used, and its outlet is connected to the water suction part of the water discharge pump, and its inlet is connected to the water source to adjust the suction pressure of the water discharge pump. It is a chemical fire engine.

This will be explained in more detail by way of examples.

The regulator 1 has a valve 2, and a stem 3 of the valve 2 is provided with a small diameter piston 4 and a large diameter piston 5. 4a
and 5a are pressure receiving parts of each piston. And pressure receiving part 4
a communicates with the inlet 6 through a conduit 8, and the pressure receiving part 5a communicates with the inlet 6 through a conduit 9.
This leads to Deroa. The cavity 11 between the two pistons 4.5 is connected to the atmosphere by a port 12.

The valve 2 has a cylindrical shape and is slidably fitted into the outer side FjlO, and the outer cylinder 10 is provided between the inlet 6 and the outlet lower part and has a plurality of side ports 10a. and the end 2a of the valve 2 and the side port 10
a constitutes a gate.

Valve 2 has a port 13. and the gap 14 on the outside of the stem 3,
Both communicate with the inlet 6 and the small diameter piston pressure receiving part 4a, and the inlet 6
The structure is such that the pressure does not directly act on the valve 2. 15
is a repulsive spring that always acts to keep valve 2 open.

As shown in FIG. 3, in the chemical fire engine A, the water discharge pump P1 and the stock solution pump P2 are driven by the same engine, and the stock solution in the foam stock solution tank is injected into the water spray by the mixer M using the stock solution pump P2. N is a nozzle.

(Function) This vJ4 regulator 1 reduces the pressure of the fire hydrant depending on the opening degree of the valve 2, and the suction pressure of the water pump becomes a predetermined pressure or less. The degree of opening of the valve 2 is determined by the balanced position of the small diameter piston 4 on which the water pressure of the inlet 6 acts, the large diameter piston 5 on which the water suction pressure of the water discharge pump acts, and the repulsive force of the spring 15. First, a case will be described in which the regulator 1 is connected to the normal water source S and the fire extinguishing foam liquid from the fire engine is discharged.

When the water pump is driven, the output lower and inlet 6 of the yi regulator
The pressure at is slightly lower than and approximately equal to atmospheric pressure. Therefore, the pressure acting on the small-diameter piston 4 and the large-diameter piston 5 is lower than the atmospheric pressure, and the force of the space 11 and the spring 15, both of which are at atmospheric pressure, is greater, so that the valve 2 remains open. Therefore, the water discharge pump absorbs water in the same way as when no regulator is used, and mixes the foam stock solution in the mixer M at the normal ratio.

Even if the water discharge pressure of the water discharge pump P1 is increased, the state in the regulator 1 does not change.

Next, when the regulator 1 is connected to the fire hydrant T and operated, the valve 2 is open, so the pressure at the inlet 6 and outlet lower becomes almost the water pressure of the fire hydrant, which is higher than atmospheric pressure, and the large-diameter piston 5 is connected to the small-diameter piston 4, and moves the valve 2 in the direction of closing by pushing the spring 15. That is, the end 2a of the valve 2 comes to close the side port 10a. When the water discharge pump is driven and the pressure at the outlet lower of this regulator 1 decreases, the pressure acting on the large diameter piston 5 decreases, and the valve 2 moves in the direction of opening. When the pressure approaches , the valve 2 automatically stops at a predetermined position, and the water discharge pump water suction part is always kept at a low pressure, for example, about 0.3 to 1.5 kg/cm'. As a result, the discharge pressure of the water discharge pump is also suppressed to a low level, allowing the mixer M to properly mix the foam stock solution.

(Example) The flow rate control of the regulator 1 uses the opening and closing of the valve 2 and the gate of the outer cylinder 10, but it is possible to use a structure in which the water flow or pressure at the inlet and outlet does not directly act on the valve body. However, other structures are also included within the scope of the present invention.

Specifically, in this regulator 1, the area ratio of the large and small diameter pistons is set to 1:15 to 1:15, and the fire hydrant pressure is set to 5 to 15 kg/
When used in conjunction with cm', the amount of water released can be increased from 300 to 350
Even if the pressure is varied to 0.01/min, the water suction part pressure of the water discharge pump is approximately 0.3 to 1.5 kg/cm'.

When using this regulator for a normal water source, if you want to obtain a sufficient flow rate, you may add a bypass passage to the regulator.

It is optional that the regulator 1 is provided in the vehicle body in advance or prepared separately and used only when the fire hydrant is used.

(Effect of the invention) By connecting the regulator to the water suction part of the water pump, the chemical fire engine of this invention can always eject high-quality fire extinguishing foam and maintain normal fire extinguishing performance without distinguishing between a normal water source and a fire hydrant. I can demonstrate it.

As in the embodiment, the valve of the regulator is provided with a vent and has a structure that is not affected by the inlet pressure, so the pressure regulating mechanism can be easily designed and a device with good performance can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a pressure regulator for a chemical fire engine according to the present invention, FIG. 2 is an explanatory diagram of the use of this chemical fire engine, and FIG. 3 is a piping system diagram. 1...Pressure regulator 2...Valve 4...Small, diameter piston 5...Large diameter piston 6...Inlet 7-...Outlet Fig. 1

Claims (2)

[Claims] (1) The valve stem has a small-diameter piston and a large-diameter piston, and the small-diameter piston handles the inlet pressure of the valve, the large-diameter piston handles the outlet pressure, and the atmosphere between the two pistons. A pressure regulator for chemical fire engines, which adjusts the water pressure of a fire hydrant by opening and closing a valve based on the balance of pressure applied to both pistons. (2) A chemical fire engine characterized in that the outlet of the regulator according to claim 1 is connected to a water suction part of a water discharge pump, and the inlet thereof is connected to a water source to adjust the suction pressure of the water discharge pump.