JP2006201855A - Automatic pressure-regulating valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an automatic pressure-regulating valve capable of realizing two-stage water drainage with a simple structure. <P>SOLUTION: The automatic pressure-regulating valve includes a pilot pressure-regulating valve 200 in which set pressure is set by a shrinking length of a pressure set spring 21, and an automatic valve 100 by which secondary pressure is regulated to predetermined control pressure by means of a main valve 10 of which opening degree is controlled, based on the set pressure being set by the pilot pressure-regulating valve 200. The pilot pressure-regulating valve 200 includes a set pressure changing means 20 in which a pressure set spring 21 is disposed with a length being variable between a first shrinking length and a second shrinking length shorter than the above first shrinking length; and a driving section 40 for generating a driving force for changing the shrinking length of the pressure set spring 21 from the first shrinking length to the second shrinking length when the secondary pressure of the automatic valve 100 is introduced. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an automatic pressure regulating valve having a pressure regulating pilot valve whose set pressure is set by a pressure setting elastic body and an automatic valve whose secondary pressure is regulated to a predetermined control pressure by this pressure regulating pilot valve. For example, in fire extinguishing in a tunnel, the present invention relates to an automatic pressure regulating valve that is optimal for a two-stage water discharge type fire extinguishing facility that performs a preliminary flow discharge (low pressure discharge) with a small flow rate before full discharge (high pressure discharge).

  In a tunnel with fire extinguishing water discharge facilities, when a fire occurs in the tunnel, the facility is activated to extinguish or suppress the fire. However, if the facility is started without notice and water discharge is started, the visibility of the section cannot be secured due to the water discharge, so that a passing vehicle in the tunnel may cause an accident (single or rear-end collision) or an evacuee can quickly There is a risk of being unable to evacuate. For this reason, when operating the said equipment, it is necessary to confirm the stop of the vehicle passing in a tunnel, the evacuation completion of an evacuee, etc.

  In order to solve the above-mentioned problems, in order to prevent the driver from being confused, the fire water discharge facility is operated safely and in a short period of time with a small amount of preliminary water discharge prior to full-scale water discharge. A two-stage water discharge type fire extinguishing system that can be made to operate is proposed.

  In addition, at the time of the start of the preliminary water discharge, the empty secondary side pipe is filled with water, but since this secondary water is almost free of secondary pressure, the automatic valve is normally fully opened and flows into the empty pipe. Fire extinguishing water becomes flash flood. And at the moment of completion of filling, water hammer may occur because the nozzle is suddenly squeezed. Conventionally, as a method of relieving the momentum of flash water flowing into an empty pipe immediately after startup, a method of maintaining an automatic valve in a half-open state when the empty pipe is filled is proposed (for example, see Patent Document 1). ).

JP 2002-13663 (page 4-5, FIGS. 1 and 2)

  However, in the conventional automatic pressure regulating valve used in such a two-stage water discharge type fire extinguishing equipment, in order to realize two-stage water discharge, a plurality of pressure regulating pilot valves are required, and a complicated water channel configuration is required. As a result, the structure was complicated and the price was expensive.

  The present invention has been made to solve the above-described problems, and can achieve two-stage water discharge with a simple configuration, thereby reducing costs and reducing fluctuations in secondary pressure. The purpose of the present invention is to obtain an automatic pressure control valve that can eliminate the fluctuation of the switching time from the noticeable discharge to the full-scale water discharge and can complete the switching from the noticeable discharge to the full-scale discharge reliably with the set switching time.

  An automatic pressure regulating valve according to the present invention is based on a pressure regulating pilot valve in which a set pressure is set by a contracted length of a pressure setting elastic body, and the set pressure in which an opening of a main valve is set by the pressure regulating pilot valve. And an automatic valve that regulates the secondary pressure to a predetermined control pressure. The pressure adjusting pilot valve includes a set pressure changing means arranged such that the pressure setting elastic body is changeable between a first contracted length and a second contracted length shorter than the first contracted length. When the primary pressure or secondary pressure of the automatic valve is introduced, a predetermined drive for changing the retracted length of the pressure setting elastic body from the first retracted length to the second retracted length A driving means for generating a force, a timer means for transmitting the driving force to the pressure setting elastic body after a lapse of a predetermined time, and changing a contracted length of the pressure setting elastic body, and according to the set pressure, Pressure adjusting means for controlling the opening degree of the main valve of the automatic valve.

  According to the present invention, two-stage water discharge can be realized by using one pressure control pilot valve, so a large number of pressure control pilot valves are not required, the water channel configuration is simplified, and the cost can be reduced. . Further, when the primary pressure or the secondary pressure of the automatic valve is introduced, the driving means is a predetermined unit for changing the contracted length of the pressure setting elastic body from the first contracted length to the second contracted length. Generates a driving force. Therefore, even if the primary pressure or the secondary pressure fluctuates, the predetermined driving force for changing the contracted length of the pressure setting elastic body does not fluctuate, so switching from the preliminary discharge to the full-scale discharge is set in advance. It will be completed in a certain switching time.

  This embodiment describes a case where the automatic pressure regulating valve of the present invention is used in a two-stage water discharge type fire extinguishing equipment that performs a preliminary flow discharge (low pressure water discharge) with a small flow rate before full-scale water discharge (high pressure water discharge) in fire extinguishing in a tunnel. However, the automatic pressure regulating valve of the present invention is not limited to the fire extinguishing equipment in the tunnel, but is an optimum automatic pressure regulating valve for equipment that needs to regulate the secondary side pipe in two stages.

  FIG. 1 is a system diagram showing a normal state of the automatic pressure regulating valve according to the present invention. 2 is a front view of the pressure regulating pilot valve in the automatic pressure regulating valve according to the present invention as seen from the pressure regulating side, FIG. 3 is a cross-sectional view taken along arrow III-III in FIG. 2, and FIG. It is sectional drawing. FIG. 5 is a view for explaining an arrangement state of a two-stage water discharge type fire extinguishing equipment in a tunnel using the automatic pressure regulating valve according to the present invention. FIG. 6 is a pressure change diagram illustrating a change in the pressure of the secondary pipe. 7 is a system diagram showing a state at the start of activation of the automatic pressure regulating valve according to the present invention, FIG. 8 is a system diagram showing a state of secondary side pipe filling in the automatic pressure regulating valve according to the present invention, and FIG. 9 is an automatic system according to the present invention. It is a systematic diagram which shows the state of the completion of secondary side piping water filling in a pressure regulation valve. FIG. 10 is a system diagram showing the state of the noticeable water discharge start in the automatic pressure regulating valve according to the present invention, FIG. 11 is a system diagram showing the state of transition from the noticeable water discharge to the full-scale water discharge in the automatic pressure regulating valve according to the present invention, and FIG. It is a systematic diagram which shows the state of the full-scale water discharge in the automatic pressure regulation valve by.

  In FIG. 1, the automatic pressure regulating valve 400 is connected to the primary side pipe 2 and the secondary side pipe 3, and the fire extinguishing that flows from the primary side pipe 2 to the secondary side pipe 3 by changing the opening degree of the main valve 10. The main valve 10 of the automatic valve 100 is opened while monitoring the automatic valve 100 for adjusting the amount of water 1 and the pressure of the secondary side pipe 3, that is, the secondary pressure (hereinafter simply referred to as “secondary pressure”). The pressure is changed in two stages, the amount of the fire-extinguishing water 1 flowing out to the secondary side pipe 3 is changed, and the secondary pressure is adjusted to, for example, a two-stage control pressure, and the secondary side pipe 3 And a filling pressure sensing on / off valve 300 that operates by sensing the filling pressure.

First, the configuration of the automatic valve 100 will be described.
The automatic valve 100 is provided with a main valve box 11, and a valve box 16 is provided above the main valve box 11. The main valve box 11 has a cylinder inside, and a piston P connected to the main valve 10 is mounted so as to be movable in the opening / closing direction of the main valve 10 while maintaining a liquid-tight state. In the main valve box 11, two chambers are formed by the piston P, that is, a lower piston chamber 12 and an upper spring chamber 13. The spring chamber 13 is provided with a piston spring 14 that urges the piston P toward the main valve 10. Moreover, the automatic valve 100 has the penetration valve 15 which is an overflow prevention opening degree maintenance means. The penetration valve 15 includes a valve box 16, a partition plate 17 that partitions the inside of the valve box 16 into two valve chambers, and a rod 18 that has a distal end portion 18 a disposed in the valve box 16 and a rear end fixed to the main valve 10. And have.
The valve box 16 is divided by a partition plate 17 into a first valve chamber 15 </ b> A near the main valve 10 and a second valve chamber 15 </ b> B far from the main valve 10. An opening 17 a is formed in the center of the partition plate 17.

The rod 18 is formed in a columnar shape having a diameter that is approximately the same as the hole diameter of the opening 17a. The rod 18 is slidable through the lower surface of the valve box 16 in the opening / closing direction of the main valve 10, that is, in the vertical direction of FIG. 1, so that the tip end 18 a extends into the valve box 16. And it is liquid-tight. The rod 18 moves upward in FIG. 1 and penetrates into the opening 17a, isolates the first valve chamber 15A and the second valve chamber 15B, and moves downward in FIG. The first valve chamber 15A and the second valve chamber 15B are communicated with each other by deviating from 17a.
A control pipe 5a extending from the secondary chamber 33 of the pressure regulating pilot valve 200 is connected to the second valve chamber 15B. A control pipe 6a is provided to communicate between the first valve chamber 15A and the piston chamber 12. That is, the control pressure supplied from the pressure regulation pilot valve 200 is transmitted in the order of the control pipe 5a, the second valve chamber 15B, the opening 17a, the first valve chamber 15A, the control pipe 6a, and the piston chamber 12 to the piston chamber 12. be introduced. The rod 18 moves in the vertical direction in FIG. 1 by the control pressure introduced into the piston chamber 12, and the opening of the main valve 10 is changed by the control pressure and the piston spring 14. As will be described in detail later, the opening degree of the main valve 10 is controlled to three opening degrees that increase in the order of the overflow prevention opening degree, the preliminary water discharge opening degree, and the full-scale water discharge opening degree.

Next, the configuration of the pressure regulating pilot valve 200 will be described with reference to FIGS.
The pressure adjustment pilot valve 200 includes a set pressure changing unit 20 that changes the set pressure of the pressure adjustment pilot valve 200 by changing the contracted length of the pressure setting spring 21 that is a pressure setting elastic body, for example, in two stages. The pressure adjusting unit 30 as a pressure adjusting means for changing the opening degree of the main valve 10 of the automatic valve 100 through monitoring of the secondary pressure according to the pressure, and the contracted length of the pressure setting spring 21 are, for example, two stages. And a timer unit 50 for creating a time for performing preliminary water discharge (low pressure water discharge).

  The set pressure changing means 20 includes a cylindrical spring case 22 for housing the pressure setting spring 21. A pair of long holes 23 are formed so as to face the wall surface of the spring case 22 so that the longitudinal direction of the holes coincides with the axial direction of the spring case 22. Further, the spring pressing plate 24 is inserted in the long holes 23 through the shaft portions 25 and is disposed in the spring case 22 so as to be movable by being guided by the long holes 23. Further, the low pressure setting ring 26 and the high pressure setting ring 26, 27 are separated from each other in the axial direction of the spring case 22, are attached to the spring case 22 in an externally fitted state, and are guided by the elongated hole 23 to move. To prevent further movement of the shaft portion 25. The pressure setting spring 21 has one end fixed to a spring pressing plate 24 and the other end fixed to a later-described frame 28, and is contracted between the spring pressing plate 24 and the frame 28. Thereby, the pressure setting spring 21 can change between the first contracted length in which the shaft portion 25 contacts the low pressure setting ring 26 and the second contracted length in which the shaft portion 25 contacts the high pressure setting ring 27. .

  The pressure adjusting unit 30 has a structure substantially similar to that of a general normally open pressure adjusting pilot valve. That is, the pressure adjusting unit 30 is provided adjacent to the spring case 22, and is made of a thin plate metal or a rubber sheet so as to be easily bent by the pressure applied to the main surface of the fram chamber 31 for introducing the secondary pressure of the automatic valve 100. The valve provided in the flow opening between the primary chamber 32 and the secondary chamber 33 through which the fram 28 constituting the one surface of the flam chamber 31 and the pressure of the primary side pipe 2, that is, the primary pressure fire-extinguishing water 1 flows. The seat 34 includes a pressure regulating valve body 35 that opens and closes the valve seat 34, and a shaft rod 36 that connects the pressure regulating valve body 35 and the fram 28. The primary chamber 32 is connected to the primary side pipe 2 via the introduction port 37a, and the secondary chamber 33 is connected to the secondary side pipe 3 via the discharge port 37b. Further, the flam chamber 31 is connected to the secondary side pipe 3 via the secondary pressure introduction port 37c.

  Note that a hole (recovery water passage hole) through which the shaft rod 36 formed between the secondary chamber 33 and the fram chamber 31 penetrates is connected to the main valve 10 of the automatic valve 100 when the automatic pressure regulating valve 400 is restored. There is a gap of a predetermined size in order to let the fire-extinguishing water 1 in the piston chamber 12 escape (this escape gap is made to have a drainage flow rate sufficiently smaller than the water supply flow rate at the time of startup). .

  Here, when the shaft portion 25 of the spring pressing plate 24 is pressed against the low pressure setting ring 26, the pressure setting spring 21 is contracted to the first contracted length. In the present embodiment, when the pressure setting spring 21 is in the first contracted length, the set pressure of the pressure regulating pilot valve 200 is the first set pressure PL (0.13 MPa in the present embodiment) for preliminary water discharge. )become. The opening of the main valve 10 of the automatic valve 100 is controlled while the secondary pressure is monitored so that the secondary pressure becomes the first set pressure PL. Thereby, the main valve 10 is maintained at the advance water discharge opening (first opening) for the advance water discharge (low pressure water discharge).

  On the other hand, when the shaft portion 25 of the spring pressing plate 24 is pressed against the high pressure setting ring 27, the pressure setting spring 21 is contracted to a second contracted length that is further contracted than the first contracted length. When the pressure setting spring 21 is at this second contracted length, the set pressure of the pressure regulating pilot valve 200 becomes the second set pressure PH (0.48 MPa in this embodiment) for full-scale water discharge, and the secondary pressure While the secondary pressure is monitored so that the pressure becomes the second set pressure PH, the opening degree of the main valve 10 of the automatic valve 100 is controlled. Thereby, the main valve 10 is maintained at the full-scale water discharge opening (second opening) for full-scale water discharge (high-pressure water discharge). The first and second opening degrees differ depending on the pressure condition of the primary side pipe 2. However, in the same equipment, the second opening is larger than the first opening.

  The preliminary water discharge opening (first opening) is determined by the water discharge nozzle pressure (in this embodiment, 0.06 MPa) that can ensure the driver's field of view, and the difference between the nozzle and the main valve is the nozzle pressure. This is the water discharge opening when the pressure adjustment pilot valve is set so that the secondary pressure of the main valve becomes the pressure calculated by adding the water head (for example, 0.05 MPa if the drop is 5 m) and the pipe loss.

  The full-scale water discharge opening (second opening) is adjusted so that the secondary pressure of the main valve becomes the pressure calculated by adding the head drop and pipe loss to the full-scale water discharge nozzle pressure (0.34 MPa in this embodiment). This is the water discharge opening when set by the pressure pilot valve.

  In order to be able to adjust the first set pressure and the second set pressure according to the state of the piping in the tunnel where the two-stage water discharge type fire extinguishing equipment is installed, the low pressure setting ring 26 and the high pressure setting ring 27 are: The position of each pressure setting spring 21 can be adjusted in the expansion / contraction direction.

  The drive unit 40 is installed in the cylinder 41, a cylindrical cylinder 41 with a bottom, a spring retainer 43 that is slidably disposed in the cylinder 41 and forms a pressurizing chamber 42 in cooperation with the cylinder 41. A stopper 44 that contacts the descending spring retainer 43 and defines the lower end position (operating position) of the spring retainer 43, and a spring that has one end fixed to the spring retainer 43 and the other end fixed to one end of a shaft 46 to be described later. A drive spring 45 that is fixed to the receiver 47 and is contracted between the spring retainer 43 and the spring receiver 47 is provided. The pressurizing chamber 42 of the cylinder 41 is provided with an introduction port 42 a to which a control pipe 7 b extending from the secondary side pipe 3 is connected, and the secondary pressure of the secondary side pipe 3 is supplied to the pressurizing chamber 42. When not introduced, the spring retainer 43 is positioned at a steady position away from the stopper. When the secondary pressure of the secondary side pipe 3 is introduced from the introduction port 42 a into the pressurizing chamber 42, this pressure acts to lower the spring retainer 43. At this time, since the spring receiver 47 does not descend instantaneously due to the presence of oil resistance of the timer means 50 described later, the spring retainer 43 quickly moves to the operating position where it abuts against the stopper 44. Therefore, the drive spring 45 is contracted by an amount corresponding to the amount of movement of the spring retainer 43, and the repulsive force (accumulated pressure) acts on the shaft 46 via the spring receiver 47 as a drive force. The amount of movement of the spring retainer 43 from the steady position to the operating position is constant regardless of the change in the secondary pressure, and the driving force generated in the driving spring 45 is always constant. The space in which the driving spring 45 of the cylinder 41 is accommodated communicates with the outside.

The timer means 50 includes an oil chamber 51 (viscous fluid chamber) filled with oil that is a viscous fluid, and a braking partition 52 that is a resistor that moves in the oil chamber 51 as the shaft 46 moves. Yes. The oil chamber 51 is a sealed space formed by a separator 54 disposed inside a bottomed cylindrical tube 53 provided adjacent to the cylinder 41, and the inside is filled with highly viscous oil. ing. The shaft 46 passes through the oil chamber 51 and is arranged so as to slide while maintaining a liquid-tight state. A spring receiver 47 is fixed to the end portion on the counter pressure setting spring 21 side. A spring retainer 48 is fixed to the end portion on the setting spring 21 side. The shaft 46 is prevented from moving toward the drive unit 40 by the spring receiver 47 abutting against the stopper 44 or the spring retainer 48 abutting against the bottom outer surface of the cylindrical body 53. In this state, an idle running distance D is secured between the shaft 46 and the spring pressing plate 24. The braking partition 52 is a disk-like member loosely penetrated by the shaft 46 and slidably contacts the inner peripheral wall surface of the oil chamber 51. Further, a piston spring 49 which is a return elastic body is contracted between the spring retainer 48 and the spring retainer 24. That is, the shaft 46 and the pressure setting spring 21 are elastically connected via the piston spring 49. The piston spring 49 is provided for monitoring the water filling, and starts to shrink before and after the water filling sensing pressure PA, thereby moving the shaft 46.
As the viscous liquid filled in the oil chamber 51, for example, water and other liquids having a small viscosity change with respect to a temperature change may be selected in addition to oil.

  The braking partition 52 divides the oil chamber 51 into a first oil chamber (first viscous fluid chamber) 51a on the pressure setting spring 21 side and a second oil chamber (second viscous fluid chamber) 51b on the side far from the pressure setting spring 21. It is divided into. Between the 1st oil chamber 51a and the 2nd oil chamber 51b, the 1st communicating path 55 which prescribes | regulates the moving speed (1st speed) while the shaft 46 moves the idle running space | interval D, and the shaft 46 is pressure. A second communication path 56 that defines a moving speed (second speed faster than the first speed) during movement while pushing and contracting the setting spring 21 is formed. At this time, the oil moves from the first oil chamber 51a to the second oil chamber 51b.

  The first communication passage 55 is a small-diameter flow passage formed to extend in the axial direction inside the side wall of the cylindrical body 53 constituting the oil chamber 51, and communicates the front end portion and the rear end portion of the oil chamber 51. . The second communication path 56 is a space formed with a part of the front end side (pressure setting spring 21 side) of the cylindrical body 53 having a larger diameter than other parts. As described above, the first communication path 55 and the second communication path 56 have the first speed as the moving speed while the shaft 46 moves in the idle running distance D, while the shaft 46 compresses and compresses the pressure setting spring 21. The purpose is to set the moving speed during the movement to a second speed higher than the first speed. The axial length of the second communication path 56 is such that the shaft 46 moves the pressure setting spring 21 from the low pressure setting ring 26. It is desirable to provide it according to the interval of movement while being compressed between the high pressure setting ring 27 and the high pressure setting ring 27.

  Since the purpose of the first communication path 55 and the second communication path 56 is as described above, the configuration of this embodiment is merely an example regarding the configuration, and the present invention is not limited to this. For example, the first communication path may be provided only on the rear end side of the oil chamber 51, and the second communication path may be further increased in diameter, and various shapes are conceivable depending on the relationship with other components.

  The second communication passage 56 is for quickly changing the set pressure of the pressure regulating pilot valve 200 from the first set pressure PL to the second set pressure PH. Preliminary water discharge (low pressure water discharge) is a low-pressure nozzle pressure that does not cause the driver to lose visibility even when water is discharged in a tunnel. If the pressure is slowly increased to full-scale water discharge (high-pressure water discharge) where a predetermined fire-extinguishing effect can be obtained, the water discharge during that time cannot be seen and the predetermined fire-extinguishing effect cannot be obtained. Because it would be a wasteful wastewater discharge, the change was made promptly.

  The first communication passage 55 is provided with a needle valve 57 as a speed adjusting means for adjusting the first speed of the shaft 46 by changing the cross-sectional area of the first communication passage 55 in size. By adjusting the needle valve 57, it is possible to finely adjust the time (10 seconds in the present embodiment) for the noticeable water discharge (low pressure water discharge) at the actual place where the fire extinguishing equipment is installed.

The braking partition 52 is provided with a through hole 58 that allows the first oil chamber 51a and the second oil chamber 51b to communicate with each other. The braking partition 52 is disposed in a loosely fitted state between the stopper 59 fixed to the shaft 46 and the closing plate 60, and is movable between the stopper 59 and the closing plate 60. The closing plate 60 is positioned on the counter pressure setting spring 21 side of the braking partition 52 and closes the through hole 58 in close contact with the braking partition 52. On the other hand, the stopper 59 is located on the pressure setting spring 21 side of the braking partition 52 and is in contact with the braking partition 52 to restrict the movement to the pressure setting spring 21 side. The through hole 58 is not blocked. . Therefore, the braking partition 52 moves to the closing plate 60 side when the shaft 46 moves forward (goes to the pressure setting spring 21 side), and at this time, the through hole 58 is closed by the closing plate 60. Does not flow from the first oil chamber 51a to the second oil chamber 51b through the through hole 58. On the other hand, when the shaft 46 moves backward, the braking partition 52 moves to the stopper 59 side, but the through hole 58 is not blocked, so that the oil passes through the through hole 58 from the second oil chamber 51b. It flows to the oil chamber 51a.
Thus, the through hole 58, the stopper 59, and the blocking plate 60 constitute a check valve that allows oil to flow only in one direction from the second oil chamber 51b to the first oil chamber 51a.

Next, the filling pressure sensing on / off valve 300 will be described.
The filling pressure sensing on / off valve 300 is a normally closed normal pilot valve that operates by sensing a predetermined set pressure. In this embodiment, it is estimated that the secondary pipe 3 is filled (two-stage water discharge type). It is set to operate at, for example, 0.09 MPa, which is a charged water sensing pressure PA (which varies depending on the state of piping in the tunnel where the fire extinguishing equipment is installed). That is, the filling pressure sensing on / off valve 300 does not open the pressure regulating valve body 63 as long as the secondary pressure is not more than the filling water sensing pressure PA. A control pipe 5b branched from the control pipe 5a is connected to the primary chamber 67 of the filling pressure sensing on / off valve 300. In addition, a control pipe 6b branched from the control pipe 6a is connected to the secondary chamber 66. That is, the filling water pressure detection opening / closing valve 300 is provided with a filling water pressure detection opening / closing valve in the middle of the control pipes 5a, 6a for introducing the primary pressure that has passed through the pressure regulating pilot valve 200 into the piston chamber 12 that lifts the main valve 10 of the automatic valve 100. Until the valve 300 is operated, the main valve 10 is disposed in parallel with the penetration valve 15 constituting the overflow prevention opening degree maintaining means for maintaining the opening degree of the main valve 10 at the overflow prevention opening degree. A pipe 7 a extending from the secondary side pipe 3 for introducing a secondary pressure into the sensing chamber 65 is further connected to the filling pressure sensing opening / closing valve 300. When the secondary pressure reaches the filling pressure sensing pressure PA and the filling pressure sensing opening / closing valve 300 is opened, the pressure water from the primary side bypasses the penetrating valve 15 that has already been closed, and this filling pressure sensing opening / closing valve 300. The control pipe 5a, the control pipe 5b, the primary chamber 67, the secondary chamber 66, the control pipe 6b, and the control pipe 6a proceed in this order, and water is supplied to the piston chamber 12 of the automatic valve 100. Is in a state where pressure can be adjusted.

The automatic pressure regulating valve 400 configured in this way is applied to a two-stage water discharge type fire extinguishing facility in a tunnel, for example, as shown in FIG. In addition, in FIG. 5, the arrangement | positioning state in one watering division is shown.
In FIG. 5, a horizontal pipe 73 is horizontally installed in the tunnel (not shown) in the longitudinal direction of the tunnel. A plurality of water spray nozzles 74 are attached to the horizontal pipe 73 at a predetermined interval. The fire extinguishing water 1 stored in the water tank 70 is supplied to the horizontal pipe 73 via the pump 71, the automatic pressure regulating valve 400 and the vertical pipe 72.

  Here, the rise by the vertical pipe 72 is 5 m, the length of the horizontal pipe 73 is 45 m, the arrangement pitch of the water spray nozzles 74 is 5 m, and the vertical pipe 72 is connected to the central position in the length direction of the horizontal pipe 73. In the case where the secondary side pipe 3 is filled with water, the charge sensing pressure PA estimated to be filled is higher than the head (0.05 MPa) of the head (0.05 m) of the water spray nozzle 74 and the automatic valve 100. A pressure lower than the pressure obtained by adding the pipe loss (depending on the flow velocity in the pipe) to the nozzle head discharge pressure (for example, 0.07 MPa) that can secure the water head (0.05 MPa) and the visibility is selected.

Next, the operation of the automatic pressure regulating valve 400 will be described.
Normal time shown in FIG.
First, in normal times, the start valve 81 is closed, and the automatic valve 100 is also closed. And the secondary side piping 3 is an empty state.

At the start of startup shown in FIG.
Next, when a fire occurs and the start valve 81 is opened, the fire extinguishing water 1 of the primary side pipe 2 is the primary of the pipe 4a, the start valve 81, the pipe 4b, and the pressure regulating pilot valve 200 as shown in FIG. The piston chamber 12 of the automatic valve 100 is filled through the chamber 32 and the secondary chamber 33, the control piping 5a, the second valve chamber 15B of the automatic valve 100, the first valve chamber 15A, and the control piping 6a. The pressure in the piston chamber 12 overcomes the urging force of the piston spring 14 and gradually raises the rod 18. As a result, the main valve 10 is opened, and the fire-extinguishing water 1 in the primary side pipe 2 gradually starts to flow into the secondary side pipe 3.

The state of the secondary side pipe filling water shown in FIG. 8 (section a in FIG. 6):
When the rod 18 rises gradually and the rod 18 closes the opening 17a, the supply of pressure water from the primary side pipe 2 to the piston chamber 12 stops, and the rise of the rod 18 stops. Therefore, the main valve 10 stops at a certain opening, and the fire extinguishing water 1 flows into the secondary side pipe 3 from the primary side pipe 2 via the automatic valve 100. The opening degree of the main valve 10 at this time is determined by the lift amount of the rod 18, but the position of the partition plate 17 can be adjusted in the moving direction of the rod 18 as described above, and the automatic pressure regulating valve 400 is used. Depending on the environment (pipe condition) to be performed, water hammer prevention and suddenly excessive water spray at the start of water discharge at the water spray nozzle 74, that is, to prevent overflow, confuse the driver of the passing vehicle Is set to an appropriate opening for avoiding the above.
In addition, the secondary pressure starts to be introduced into the pressurizing chamber 42 of the drive unit 40 via the control pipe 7a and the control pipe 7b. As a result, the spring retainer 43 is lowered.

State of completion of secondary side pipe filling shown in FIG. 9:
When the secondary side pipe 3 is filled with the fire extinguishing water 1, a constant pressure is generated in the secondary side pipe 3, the pressurizing chamber 42 starts to be pressurized, and the spring retainer 43 is pressed against the stopper 44. It is done. As a result, the driving spring 45 is contracted by a predetermined amount, and a driving force is generated. Due to the driving force of the driving spring 45, the shaft 46 gradually starts to descend. Therefore, the shaft 46 approaches the spring pressing plate 24 while the piston spring 49 contracts. At this time, the shaft 46 moves at a first speed defined by the first communication path 56.

  Here, the secondary pressure gradually increases while the fire-extinguishing water 1 rises up the vertical pipe 72 (5 m) (corresponding to the section from 0 to A in FIG. 6). Thereafter, the pressure does not increase when the horizontal pipe 73 is filled with water (corresponding to the section from point A to point B in FIG. 6). And when all the horizontal piping 73 is also filled with water, a pressure will begin to rise again (equivalent to the area of the point B-point C of FIG. 6).

  In this automatic pressure regulating valve 400, the automatic valve 100 is provided with the penetrating valve 15 which is an overflow prevention opening degree maintaining means, so that the opening degree of the main valve 10 during filling is smaller than the noticeable water discharge opening degree. The flow prevention opening is maintained. Therefore, as shown in FIG. 6, water hammer does not occur at the time of completion of water filling (in the conventional device, water hammer occurs as shown by the dotted line in FIG. 6). In addition, since there is no discharge beyond the preliminary discharge flow rate at the start of the preliminary discharge, there is no excessive eruption (overflow) due to flash floods at the start of the discharge, and it is possible to avoid surprisingly surprise the driver. Can be prevented.

State of notice water discharge shown in FIG. 10 (section c in FIG. 6):
When the filling of the fire-extinguishing water 1 into the secondary side pipe 3 is completed and the charge detection pressure PA is reached, the charge pressure detection on / off valve 300 is actuated (point C in FIG. 6). The pressure regulating valve body 63 is opened. Therefore, the pressure water is the primary of the control pipe 4 a, the start valve 81, the control pipe 4 b, the primary and secondary chambers 32 and 33 of the pressure regulating pilot valve 200, the control pipe 5 a, the control pipe 5 b, and the primary pressure detection valve 300. The piston chamber 12 of the automatic valve 100 is filled through the chamber and secondary chambers 67 and 66, the control pipe 6b, and the control pipe 6a. As a result, the pressure in the piston chamber 12 is increased, the rod 18 is pushed up, and the main valve 10 is further opened. The opening degree at this time is the preliminary water discharge opening degree by the first set pressure set by the first contracted length of the pressure setting spring 21. Then, preliminary water discharge (low pressure water discharge) from the water spray nozzle 74 is started.

  Then, the shaft 46 moves the idle running distance D at a first speed defined by the first communication path 55 while pressing and contracting the piston spring 49. While the shaft 46 is moving the idle running interval D (in this embodiment, about 10 seconds), preliminary water discharge is performed (section from the movement start point of the shaft 46 to the point E in FIG. 6). The start of the movement of the shaft 46 substantially coincides with the time when the secondary pressure reaches the charged water detection pressure PA.

The state of transition from the preliminary discharge shown in FIG. 11 to the full-scale discharge (D section in FIG. 6):
When the shaft 46 moves in the idle running space D and reaches the spring pressing plate 24, the speed of the shaft 46 increases from the first speed to the second speed due to the effect of the second communication path 56, and the pressure setting spring 21 is instantaneously moved to the first speed. The length is changed from the first reduced length to the second reduced length (section from point E to point F in FIG. 6).

State of full-scale water discharge shown in FIG. 12 (section o in FIG. 6):
The shaft portion 25 comes into contact with the high pressure setting ring 27 and the lowering of the shaft 46 is stopped. Thereby, the contracted length of the pressure setting spring 21 is set to the second contracted length. Therefore, the accumulated pressure of the pressure setting spring 21 is transmitted to the pressure regulating valve body 35 through the fram 28, and the pressure regulating valve body 35 is changed from a very narrowed state to a widely opened state. That is, the set pressure of the pressure regulating pilot valve 200 is quickly switched from the first set pressure to the second set pressure. Thereby, the pressure of the primary side pipe 2 is again introduced into the piston chamber 12 of the automatic valve 100, and the rod 18 rises again. And the main valve 10 opens rapidly to the full-scale water discharge opening degree by a 2nd setting pressure. Thereafter, full-scale water discharge (high-pressure water discharge) is performed (section after point F in FIG. 6).

Recovery action:
When the full-scale water discharge ends and the automatic pressure regulating valve 400 is restored, the pressure water is not supplied to the piston chamber 12 of the automatic valve 100 when the start valve 81 is closed. Therefore, the rod 18 starts to move in the closing direction by the force of the piston spring 14 that urges the rod 18 connected to the main valve 10 in the closing direction. At this time, since the opening degree of the main valve 10 is still an opening degree between the preliminary water discharge opening degree and the full-scale water discharge opening degree, the filling water pressure detection opening / closing valve 300 is in the open state, and the inside of the piston chamber 12 When the pressure water is pushed out, it enters the secondary chamber 33 of the pressure regulating portion 30 of the pressure regulating pilot valve 200 via the filling pressure sensing on / off valve 300, and passes through the clearance for the hole through which the shaft rod 36 passes. The water is discharged from the chamber 31 to the secondary side pipe 3 through the control pipes 7c and 7a.

  When the main valve 10 is throttled and the pressure in the secondary side pipe 3 becomes lower than the charge detection pressure PA of the charge pressure detection on / off valve 300, the charge pressure detection on / off valve 300 is closed, but before that, When the pressure lower than the set pressure PL is higher than the charged water sensing pressure PA, the penetration valve 15 opens, so that the drainage flow path is secured via the penetration valve 15 and the main valve 10 is closed. It reaches. After the main valve 10 is closed, the pressure of the secondary side pipe 3 remains as a head of the head due to the residual water filled in the secondary side pipe 3, and is then drained by an automatic drain valve (not shown).

  As the secondary pressure is reduced, the pressurizing chamber 42 of the pressure regulating pilot valve 200 is depressurized, and the shaft 46 is pushed up by the accumulated pressure of the piston spring 49. Since the through hole 58 of the brake partition 52 loosely fitted to the shaft 46 is opened, oil passes through the through hole 58 having a wide opening together with the first communication path 56, and the shaft 46 quickly returns to the original position. Since the shaft 46 returns to the original position, the spring pressing plate 24 expands by the restoring force of the pressure setting spring 21, returns to the position of the low pressure setting ring 26, and the pressure adjusting unit 30 is also restored. Further, since the shaft 46 returns to the original position, the spring pressing plate 43 returns to the initial position by the restoring force of the driving spring 45, and the pressure water in the pressurizing chamber 42 is supplied to the secondary pipe via the control pipes 7b and 7a. 3 and the drive unit 40 is also restored.

In the above-described embodiment, the set pressure changing means 20 is provided with the check valve including the through hole 58, the stopper 59, and the closing plate 60 in the braking partition 14. For example, the first oil chamber 51a and the second oil pressure chamber A separate check valve structure that allows oil to flow only when the shaft 46 as the moving body moves backward may be provided in the pipe separately by providing a pipe between the oil chamber 51b and the like.
In the above embodiment, a normally open valve structure is used as the pressure adjusting part of the pressure adjusting pilot valve. However, a normally closed valve structure may be used as the pressure adjusting part.
In the above embodiment, the secondary pressure of the secondary side pipe 3 is introduced into the pressurizing chamber 42 of the drive unit 40 to generate a drive force in the drive spring 45. The primary pressure of the primary side pipe 2 may be introduced into the pressure chamber 42 and the driving spring 45 may generate a driving force.

  Moreover, in the said Example, although the setting pressure was made into two steps, you may enable it to set a pressure in the several step beyond it. In this case, for example, the high pressure setting ring 27 may be provided, and further, instead of the low pressure setting ring 26, several latches may be provided at pressure setting positions in a range where the water discharge pressure can ensure the visibility. These some latches are provided so that the spring pressing plate 24 passes in the direction in which the pressure setting spring 21 becomes longer, and the pressing plate 24 engages in the direction in which the pressure setting spring 21 becomes shorter. It can be surpassed by more than power. In this way, at the time of notice water discharge, water will be sprayed in such a way that the water discharge pressure will gradually increase from a lower pressure (small amount of water) within the range where visibility can be ensured, so a safer notice will be given to the traveling vehicle. Can do.

Moreover, in the said Example, although the setting pressure was made into multiple steps, you may enable it to set a setting pressure arbitrarily. In that case, for example, only the high pressure setting ring 27 is provided, and the spring pressing plate 24 is brought into contact with the shaft 46 from the beginning. In this way, water spraying is performed so that the water discharge pressure increases steplessly from the low pressure within the range of visibility when the preliminary water discharge is performed, so that it is possible to make a safer notification to the traveling vehicle and the structure is simple. . In addition, when it exceeds the water discharge pressure which can ensure a visual field, that is, after the preliminary water discharge, if the second communication path 56 passes, the water is quickly put into full-scale water discharge, so that fire extinguishing is effectively performed.
In the above description, the position of the latch or the like is made longer than the position where the water discharge pressure can ensure the field of view, but a latch or the like may be provided at a position shorter than that position.

  Further, in the above embodiment, an example of one watering section of the two-stage water discharge type fire extinguishing equipment in the tunnel as shown in FIG. 5 is shown, but this watering section is installed in a plurality of tunnels in the longitudinal direction. The fire extinguishing equipment of a section that is notified by a remote control panel (not shown) may be operated based on a notification signal of a fire detector (not shown) in the section.

  In that case, it is possible to spray only the section of the fire detector that has been reported by two-stage water discharge, but simultaneously spray the two sections of the fired section and the section in front of the direction of travel of the vehicle simultaneously. You may do it. In this case, the water discharge stop control may be performed within a predetermined time so that the section on the front side in the traveling direction ends only with the preliminary water discharge.

  Alternatively, in the section where the alarm was issued, the two-stage water discharge is started first, and the two stages are sequentially delayed from the rear section closest to the first section to the front section among the multiple sections on the front side in the traveling direction. You may make it start watering and sprinkle. In this case, water spraying in a plurality of sections on the front side in the traveling direction of the vehicle may be stopped before entering full-scale water discharge.

  Alternatively, water spraying in a plurality of sections on the front side in the traveling direction may be repeated on and off within a predetermined time by using a control panel (not shown) to repeat the notice water discharge. In this way, the preliminary water discharge can be performed forever. In this case, if the on / off timing or cycle is made different in each section, it is possible to reduce or eliminate the noticeable water discharge all at once, and to spray water without losing the function of the notice.

  As described above, in the present invention, the pressure adjustment pilot valve in which the set pressure is set by the contracted length of the pressure setting elastic body, and the opening of the main valve are controlled based on the set pressure set by the pressure adjustment pilot valve. Thus, in the automatic pressure regulating valve having the automatic valve in which the secondary pressure is regulated to a predetermined control pressure, the pressure regulating pilot valve has a pressure setting elastic body shorter than the first reduced length and the first reduced length. When the primary pressure or secondary pressure of the automatic valve is introduced, and the primary pressure or secondary pressure of the automatic valve is introduced, the compression length of the pressure setting elastic body is reduced to the first compression length. A driving means for generating a predetermined driving force for changing from the length to the second contracted length; and the driving force is transmitted to the pressure setting elastic body after a lapse of a predetermined time, and the contracted length of the pressure setting elastic body Timer means to change the pressure, and pressure regulation to control the opening of the main valve of the automatic valve according to the set pressure It includes a stage, a. Therefore, the pressure can be regulated by changing the secondary pressure of the automatic valve with a single pressure regulating pilot valve, and the cost can be reduced with a simple configuration. In addition, the driving force generated in the driving means is not affected by the fluctuation of the introduced primary pressure or secondary pressure, and is always constant, and switching from the preliminary discharge to the full-scale discharge is ensured at a preset switching time. To be completed. Furthermore, if this automatic pressure regulating valve is applied to a fire extinguishing equipment in a tunnel, it is possible to obtain a two-stage water discharge fire extinguishing equipment in a tunnel that can reduce the cost with a simple configuration.

  The drive means includes a cylinder provided with an inlet for primary or secondary pressure of an automatic valve, and a spring retainer disposed in the cylinder so as to be slidable while maintaining a liquid-tight state in a direction contacting and separating from the inlet. Provided on the opposite side of the introduction port with the spring retainer sandwiched between the cylinder, a stopper for defining the amount of movement of the spring retainer in a direction away from the introduction port, and on the opposite side of the introduction port of the spring retainer. When the primary pressure or the secondary pressure is not introduced into the space in the cylinder facing the introduction port, the spring presser extends so as to be positioned at a steady position away from the stopper, and the primary pressure or the secondary pressure is A drive spring that generates a driving force by contracting so that when the pressure is introduced, the spring retainer moves from the steady position to an operating position that contacts the stopper. Therefore, a driving means that can always generate a constant driving force without being influenced by fluctuations in the introduced primary pressure or secondary pressure is realized with a simple configuration.

  The timer means is disposed between the set pressure changing means and the drive means, and the viscous fluid chamber filled with the viscous fluid, and the pressure setting elastic body extending and contracting through the viscous fluid chamber in a liquid-tight state. A shaft movably disposed in the direction, a resistor that moves in the viscous fluid chamber in conjunction with the movement of the shaft, a spring receiver that is fixed to one end of the shaft and to which the driving force of the driving spring is transmitted, A return elastic body that elastically connects the other end of the shaft and the pressure setting elastic body, and when the driving force is transmitted through the spring receiver, the shaft moves the resistor in the viscous fluid. The elastic body moves while contracting the return elastic body against the resistance received, and comes into contact with the pressure setting elastic body after a lapse of a predetermined time, and then moves while changing the contracted length of the pressure setting elastic body. Yes. Therefore, when this automatic pressure regulating valve is applied to a two-stage water discharge fire extinguishing facility in a tunnel, the time for performing preliminary water discharge can be created with an easy configuration.

  Further, the timer means moves the shaft until it comes into contact with the pressure setting elastic body while contracting the return elastic body at the first speed, and after contacting the pressure setting elastic body, at a second speed higher than the first speed. The pressure setting elastic body is configured to move while changing the contracted length. Therefore, when this automatic pressure control valve is applied to a two-stage water discharge type fire extinguishing equipment in a tunnel, it is possible to quickly switch from preliminary discharge to full-scale water discharge, and the water discharge during the changeover is not given visibility and is not specified. Therefore, it is possible to provide a more effective two-stage water discharge type fire extinguishing equipment in the tunnel without causing a halfway wasteful discharge.

  The resistor is disposed so as to separate the viscous fluid chamber into a first viscous fluid chamber on the set pressure changing means side and a second viscous fluid chamber on the drive means side. Then, when the resistor moves in conjunction with the movement of the shaft until the resistor contracts the return elastic body and contacts the pressure setting elastic body, the viscous fluid is recirculated from the first viscous fluid chamber to the second viscous fluid chamber. And the pressure setting elasticity after the resistor abuts against the pressure setting elastic body, the first communication path defining the moving speed of the shaft as the first speed, and a passage cross-sectional area larger than the first communication path. When moving in conjunction with the movement of the moving shaft while changing the contracted length of the body, the viscous fluid is recirculated from the first viscous fluid chamber to the second viscous fluid chamber, so that the moving speed of the shaft is increased. And a second communication path that defines two speeds. Therefore, when this automatic pressure regulating valve is applied to a two-stage water discharge type fire extinguishing equipment in a tunnel, an automatic pressure regulating valve capable of promptly switching from preliminary water discharge to full-scale water discharge can be realized with a compact configuration.

  Further, the automatic valve is controlled so that the opening of the main valve is at least two stages of opening: a preliminary water discharge opening and a full-scale water discharge opening larger than the preliminary water discharge opening. Therefore, this automatic pressure regulating valve can be easily applied to the two-stage water discharge type fire extinguishing equipment in the tunnel.

  In addition, it is further equipped with a charge detection on / off valve that operates by sensing the charge pressure of the secondary pipe connected to the automatic valve, and the automatic valve opens the main valve until the charge detection on / off valve operates. An overflow prevention opening degree maintaining means for maintaining the degree at an overflow prevention opening degree smaller than the preliminary water discharge opening degree is provided. Thus, water hammer can be prevented and overflow at the start of water discharge can be prevented.

  The automatic pressure regulating valve of the present invention is an automatic pressure regulating valve suitable for a two-stage water discharge type fire extinguishing facility that performs a preliminary flow discharge (low pressure water discharge) with a small flow rate before full-scale water discharge (high pressure water discharge) in fire extinguishing in a tunnel.

It is a systematic diagram which shows the state of the normal time in the automatic pressure regulation valve by this invention. It is the front view which looked at the pressure regulation pilot valve in the automatic pressure regulation valve by this invention from the pressure regulation part side. FIG. 3 is a cross-sectional view taken along the line III-III in FIG. 2. FIG. 4 is a cross-sectional view taken along arrow IV-IV in FIG. 2. It is a figure explaining the arrangement | positioning state of the two-stage water discharge type fire extinguishing equipment in a tunnel using the automatic pressure regulation valve by this invention. It is a pressure change figure explaining the change of the pressure of secondary side piping. It is a systematic diagram which shows the state at the time of the starting start in the automatic pressure regulation valve by this invention. It is a systematic diagram which shows the state in the secondary side piping filling water in the automatic pressure regulating valve by this invention. It is a systematic diagram which shows the state of the secondary side piping filling completion in the automatic pressure regulating valve by this invention. It is a systematic diagram which shows the state of the noticeable water discharge start in the automatic pressure regulation valve by this invention. It is a systematic diagram which shows the state of the transition from the preliminary | backup water discharge in the automatic pressure regulation valve by this invention to full-scale water discharge. It is a systematic diagram which shows the state of the full-scale water discharge in the automatic pressure regulation valve by this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Main valve, 15 Penetration valve (overflow prevention opening maintenance means), 20 Set pressure change means, 21 Pressure setting spring (pressure setting elastic body), 30 Pressure adjustment part (pressure adjustment means), 40 Drive part (drive means) ), 41 cylinder, 42a inlet, 43 spring retainer, 44 stopper, 45 drive spring, 46 shaft, 47 spring receiver, 49 piston spring (return elastic body), 50 timer means, 51 oil chamber (viscous fluid chamber), 51a First oil chamber (first viscous fluid chamber), 51b Second oil chamber (second viscous fluid chamber), 52 Partition for braking (resistor), 55 First communication path, 56 Second communication path, 58 Through hole (Check valve), 59 stopper (check valve), 60 closing plate (check valve), 100 automatic valve, 200 pressure regulating pilot valve, 300 filling pressure sensing on / off valve, 400 automatic pressure regulating valve.

Claims (5)

A pressure adjusting pilot valve in which a setting pressure is set according to the contracted length of the pressure setting elastic body, and the opening of the main valve is controlled based on the setting pressure set by the pressure adjusting pilot valve, so that the secondary pressure In an automatic pressure regulating valve having an automatic valve regulated to a predetermined control pressure,
The pressure regulating pilot valve
A set pressure changing means arranged such that the pressure setting elastic body is changeable between a first contracted length and a second contracted length shorter than the first contracted length;
When primary pressure or secondary pressure of the automatic valve is introduced, a predetermined driving force for changing the contracted length of the pressure setting elastic body from the first contracted length to the second contracted length Driving means for generating
Timer means for transmitting the driving force to the pressure setting elastic body after a lapse of a predetermined time and changing the contracted length of the pressure setting elastic body;
Pressure adjusting means for controlling the opening degree of the main valve of the automatic valve according to the set pressure,
An automatic pressure regulating valve characterized by comprising:   The driving means is slidably disposed while maintaining a liquid-tight state in a direction in which the automatic valve is in contact with and away from the inlet, and a cylinder provided at the inlet of the primary or secondary pressure of the automatic valve. A spring retainer provided, a stopper provided on the opposite side of the introduction port with the spring retainer sandwiched between the cylinders, and a movement amount of the spring retainer in a direction away from the introduction port, and the spring retainer When the primary pressure or secondary pressure is not introduced into the space in the cylinder that is provided on the opposite side of the introduction port and faces the introduction port, the spring retainer is positioned at a steady position that is separated from the stopper. When the primary pressure or secondary pressure is introduced into the space, the spring retainer contracts so as to move from the steady position to an operating position that contacts the stopper, and the driving force Automatic pressure regulating valve according to claim 1, characterized in that it comprises a drive spring for generating a. The timer means is disposed between the set pressure changing means and the driving means, and passes through the viscous fluid chamber filled with the viscous fluid and the viscous fluid chamber in a liquid-tight state, and the pressure setting elasticity. A shaft disposed so as to be movable in the expansion and contraction direction of the body, a resistor that moves in the viscous fluid chamber in conjunction with the movement of the shaft, and the driving force of the driving spring fixed to one end of the shaft And a return elastic body that elastically connects the other end of the shaft and the pressure setting elastic body,
When the driving force is transmitted through the spring receiver, the shaft moves while contracting the return elastic body against resistance received when the resistor moves in the viscous fluid, 3. The automatic pressure regulating valve according to claim 2, wherein the pressure adjusting elastic body abuts on the pressure setting elastic body after the lapse of the predetermined time, and thereafter moves while changing a contracted length of the pressure setting elastic body.   The timer means moves at a first speed until the shaft abuts against the pressure setting elastic body while contracting the return elastic body, and after contacting the pressure setting elastic body, is faster than the first speed. 4. The automatic pressure regulating valve according to claim 3, wherein the automatic pressure regulating valve is configured to move at a second speed while changing a contracted length of the pressure setting elastic body. The resistor is arranged to separate the viscous fluid chamber into a first viscous fluid chamber on the set pressure changing means side and a second viscous fluid chamber on the drive means side;
The viscous fluid is moved from the first viscous fluid chamber to the second viscous fluid when the resistor moves in conjunction with the movement of the shaft until the resistor elastically contracts the return elastic body. A first communication path that recirculates to the fluid chamber and regulates the moving speed of the shaft to the first speed;
It is formed in a passage cross-sectional area larger than the first communication passage, and interlocks with the movement of the shaft that moves while changing the contracted length of the pressure setting elastic body after the resistor contacts the pressure setting elastic body A second communication path for recirculating the viscous fluid from the first viscous fluid chamber to the second viscous fluid chamber and defining the moving speed of the shaft at the second speed when moving.
The automatic pressure regulating valve according to claim 4, further comprising:

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