JP7005555B2 - Pilot governor and pilot gas governor using it - Google Patents

Description

The present invention relates to a pilot governor used for controlling gas pressure and a pilot type gas governor using the pilot governor to prevent a decrease in secondary pressure due to an increase in gas usage on the secondary side.

For example, in the middle of a supply path for city gas or the like, there is a place where the pressure in the pipeline is switched, and a gas governor (pressure regulator) is provided in that part.

The schematic configuration of an example of the gas governor is shown in FIG. The gas governor in the figure is referred to as a pilot type gas governor, and is shown in the following Patent Document 1 and the like.

In the pilot type gas governor 30 of FIG. 13, the main governor (main body moving part) 33, which is incorporated between the primary side pipeline 31 and the secondary side pipeline 32 and reduces the high pressure on the primary side to flow to the secondary side, A pilot governor 1, an orifice 34, etc. that control the operation of the main governor 33 are included, and the change in the secondary pressure is small due to the pressure adjustment of the secondary pressure (hereinafter referred to as the secondary pressure) by these devices. It can be suppressed.

In the pilot governor 1 of FIG. 13, the first diaphragm (upper diaphragm) 3 and the second diaphragm (lower diaphragm) 4 provided in the casing 2 are connected via the holder 5, and the first diaphragm 3 is inside the casing 2. A drive pressure chamber (load pressure chamber) 6 located between the second diaphragm 4 and a secondary pressure chamber 7 located above the first diaphragm 3, and an atmospheric pressure chamber 8 located below the second diaphragm 4. Is forming.

Further, the control pressure fluid introduction passage 9, the supply valve 10 installed at the outlet of the introduction passage 9 to the drive pressure chamber 6, and the drive pressure chamber 6 and the secondary pressure chamber 7 communicate with each other. The exhaust valve 11 for switching the state and the spring 12 for adjusting the urging force for urging the holder 5 from the atmospheric pressure chamber 8 side to the secondary pressure chamber 7 side are provided inside the casing 2. There is.

The secondary pressure chamber 7 is connected to the balance pressure chamber 33b of the secondary side pipeline 32 and the main governor 33, and is incorporated in the middle of the path connecting the primary side pipeline 31 and the introduction passage 9 depending on the form of the pressure regulator. It is also connected to the regulating pressure chamber of the pressure reducing valve (not shown).

The introduction passage 9 is connected to the primary side pipeline 31, and the drive pressure chamber 6 is connected to the loading pressure chamber (drive pressure chamber) 33d of the main governor 33.

As shown in FIG. 14, in the supply valve 10, the valve portion opening is controlled by the difference in the pressure receiving state between the first diaphragm 3 and the second diaphragm 4, and the first diaphragm 3 and the spring 12 are likely to move the holder 5 upward. The valve portion opening is kept constant at a position where the force to move the holder 5 downward and the force to move the holder 5 downward are balanced.

In the gas governor that operates the main governor 33 by using the driving pressure of the pilot governor 1 of the example, the communication between the primary side pipeline 31 and the secondary side pipeline 32 is cut off by the on-off valve 33a of the main governor 33. When the pressure in the secondary side pipeline 32 is used and reduced, the pressure in the secondary pressure chamber 7 of the pilot governor 1 is reduced.

Therefore, the balance of the forces that the first and second diaphragms 3 and 4 of the pilot governor 1 try to move the holder 5 in opposite directions is lost, and the first and second diaphragms 3 and 4 are pushed by the spring 12. Then, it moves upward together with the holder 5, and the valve portion opening degree of the supply valve 10 becomes large.

As a result, the amount of the control pressure fluid introduced into the drive pressure chamber 6 from the primary side pipeline 31 increases, and the pressure in the drive pressure chamber 6 (the drive pressure supplied to the main governor 33) increases.

The pressure in the drive pressure chamber 6 flows into the loading pressure chamber 33d of the main governor 33, and the on-off valve 33a opens due to the pressure increase in the loading pressure chamber 33d, from the primary side pipeline 31 to the secondary side pipeline 32. High pressure gas flows in.

The driving pressure increases until the flow rate from the on-off valve 33a of the main governor 33 reaches a flow rate corresponding to the amount of gas used on the secondary side.

When the drive pressure rises to the control target pressure (the pressure at which the flow rate from the on-off valve 33a becomes the flow rate according to the amount of gas used on the secondary side), the force acting against the holder 5 inside the pilot governor 1 is applied. Balance again.

Due to the effect of the increase in driving pressure, the holder 5 is moved to the atmospheric pressure chamber 8 inside the pilot governor 1.
The force pushing to the side is increasing, and the secondary pressure is reduced by that amount, and the force acting against the holder 5 is balanced.

Therefore, the secondary pressure decreases as the amount of gas used increases.

Further, the force that the driving pressure acts to push the holder 5 toward the atmospheric pressure chamber 8 at this time is due to the difference in the pressure receiving states of the first and second diaphragms 3 and 4.

Contrary to the above state, when the amount of gas used on the secondary side of the gas supply path decreases, the pressure in the secondary pressure chamber 7 of the pilot governor 1 rises, and the holder 5 moves to the atmospheric pressure chamber 8 side. As a result, the on-off valve 33a is closed, and the exhaust valve 11 is opened in conjunction with this, so that the driving pressure in the driving pressure chamber 6 is discharged to the secondary pressure chamber 7 side, and the governor is stopped.

Japanese Unexamined Patent Publication No. 2004-252706

In the pilot type gas governor, the driving pressure generated by the pilot type gas governor in response to the decrease in the secondary pressure is sent to the main governor as a control signal, but the conventional pilot type gas governor shown in FIG. 13 is on the secondary side due to its characteristics. When the amount of gas used in the water is increased, the secondary pressure is lowered by a constant value (see static characteristic A in FIG. 15).

This is because the driving pressure is generated by utilizing the difference in the pressure receiving state between the first diaphragm and the second diaphragm of the pilot governor.

The decrease in the secondary pressure can be suppressed to a small extent by approximating the pressure receiving states of the first diaphragm and the second diaphragm of the pilot governor (reducing the difference in the pressure receiving states) (see static characteristic B in FIG. 15).

However, when this method is adopted, the response behavior of the drive pressure when the gas usage changes becomes hypersensitive and the control by the pilot governor becomes unstable, and the secondary pressure P2 swings greatly as shown in FIG. Will not stop. Therefore, there is a limit to approximating the pressure receiving states of the first diaphragm and the second diaphragm of the pilot governor.

As shown in FIG. 17, in the pilot governor in which the difference between the pressure receiving states of the first diaphragm and the second diaphragm is set to be large, the secondary pressure P2 swings at the initial stage of control, but the swing converges early.

Therefore, the conventional pilot governor sets a large difference in the pressure receiving state between the first diaphragm and the second diaphragm, but as can be seen from FIG. 17, the pilot governor has a secondary pressure after the runout has converged. A decrease in P2 is inevitable.

The problem of the decrease in the secondary pressure due to the increase in the amount of gas used on the secondary side is particularly remarkable in the gas supply path of the application in which a large amount of gas is used.

Therefore, it is an object of the present invention to provide a pilot governor that stabilizes the operation when the secondary pressure changes, and a pilot type gas governor that prevents the secondary pressure from decreasing due to an increase in the amount of gas used on the secondary side. It is supposed to be.

In order to solve the above problems, in the present invention,
A drive pressure chamber that introduces the primary pressure, a secondary pressure chamber that introduces the secondary pressure regulated by the main governor, an atmospheric pressure chamber, and a regulated pressure arranged between the drive pressure chamber and the atmospheric pressure chamber. With a casing that has a chamber inside,
A first diaphragm that separates the drive pressure chamber and the secondary pressure chamber, a second diaphragm that separates the drive pressure chamber and the adjustment pressure chamber, and a third diaphragm that separates the adjustment pressure chamber and the atmospheric pressure chamber. ,
A holder arranged in the casing and supporting the inner peripheral side of the first, second, and third diaphragms,
A supply valve that increases or decreases the amount of control pressure fluid introduced from the primary side pipeline to the drive pressure chamber by the displacement of the holder.
An exhaust valve that communicates the drive pressure chamber with the secondary pressure chamber in conjunction with the valve closing operation of the supply valve.
A spring installed in the atmospheric pressure chamber and urging the holder toward the secondary pressure chamber,
A passage connecting the driving pressure chamber and the adjusting pressure chamber,
Has an aperture and is placed in that aisle,
The difference in the pressure receiving state between the first diaphragm and the second diaphragm is large.
The first diaphragm and the third diaphragm have similar pressure receiving states.
The valve opening of the supply valve is maintained at zero or constant at a position where the force for moving the holder toward the secondary pressure chamber and the force for moving the holder toward the atmospheric pressure chamber are balanced. And
During the transient response to the decrease in secondary pressure, the position of the holder is controlled by the first diaphragm and the second diaphragm.
Provided is a pilot governor in which the position control of the holder is performed by the first diaphragm and the third diaphragm when the pressures of the driving pressure chamber and the adjusting pressure chamber are close to or equal to each other and stable.

The "pressure receiving state" referred to here is determined by the difference in the design shape and mounting position of each diaphragm.

If the difference in the pressure receiving state is large, the difference in the thrust (force for moving the holder) generated by the two diaphragms having different pressure receiving states becomes large.

Further, if the difference in the pressure receiving state is close, the difference in the thrust generated by the two diaphragms having the similar pressure receiving state becomes small.

The second diaphragm produces a larger thrust than the first diaphragm due to the difference in the pressure receiving state.

The passage connecting the driving pressure chamber and the adjusting pressure chamber may be provided outside the casing or may be provided in the holder inside the casing.

The third diaphragm can include a mounting position adjusting mechanism in the holder so that the mounting position with respect to the holder can be changed.

Further, a valve is closed between the drive pressure chamber and the adjustment pressure chamber when the pressure PW in the drive pressure chamber and the pressure PC in the adjustment pressure chamber have a relationship of PW ≧ PC, and the above relationship is broken. An exhaust valve or a check valve that opens when PW <PC and releases the pressure in the adjustment pressure chamber to the drive pressure chamber can be provided.

The check valve and the exhaust valve can also be provided on the outside of the casing or on the holder.

Further, the diaphragm provided in the passage outside the casing can be a variable diaphragm.

In addition, a tank communicating with the adjusting pressure chamber may be provided outside the casing to increase the substantial volume of the adjusting pressure chamber, or a fixed throttle or variable in the passage connecting the tank and the adjusting pressure chamber. It is also possible to add more apertures.

The present invention includes a loading pressure chamber and a balance pressure chamber partitioned by a diaphragm, and an on-off valve for switching the communication state between the primary side pipeline and the secondary side pipeline, and between the primary side pipeline and the secondary side pipeline. Combining the main governor, which is incorporated to reduce the pressure on the primary side and flows to the secondary side, with the pilot governor of the present invention described above,
The drive pressure chamber of the pilot governor was connected to the primary side pipeline, and the secondary pressure chamber was connected to the balance pressure chamber of the secondary side pipeline and the main governor.
Further, a pilot type gas governor in which the drive pressure chamber is connected to the loading pressure chamber of the main governor is also provided.

The pilot governor of the present invention newly provides an adjusting pressure chamber that is partitioned between the driving pressure chamber and the driving pressure chamber by a second diaphragm and between the atmospheric pressure chamber and the atmospheric pressure chamber by a third diaphragm, and the adjusting pressure chamber is provided. Is communicated with the drive pressure chamber through a passage in which a throttle is installed.

Since it is configured in this way, when the pressure in the secondary pressure chamber decreases and the amount of the control pressure fluid introduced into the drive pressure chamber from the primary side pipeline increases, the pressure in the drive pressure chamber becomes said. The pressure is higher than the pressure in the adjusting pressure chamber, and then the pressure in the driving pressure chamber flows to the adjusting pressure chamber through the passage where the throttle is installed, and the driving pressure chamber and the adjusting pressure chamber become the same pressure.

Therefore, during the transient response to the pressure drop in the secondary pressure chamber, the position control of the holder (control of the valve portion opening of the supply valve) by the first diaphragm and the second diaphragm having a large pressure receiving state difference is dominant. When the operating state of the governor becomes stable as the driving pressure chamber and the adjusting pressure chamber become the same pressure over time, the position control of the holder is switched to the control by the first diaphragm and the third diaphragm.

Since the first diaphragm and the third diaphragm are similar in pressure receiving state,
When the control is switched to the first diaphragm and the third diaphragm, the secondary pressure becomes stable and the pressure drop is suppressed to a very small state or zero.

In addition, in the case where the mechanism for adjusting the mounting position of the third diaphragm with respect to the holder is included, the mounting position of the third diaphragm can be changed to change the pressure receiving state of the third diaphragm.

Further, when the pressure PC in the adjusting pressure chamber becomes larger than the pressure PW in the driving pressure chamber between the driving pressure chamber and the adjusting pressure chamber, a valve is opened to transfer the pressure in the adjusting pressure chamber to the driving pressure chamber. Those equipped with a release exhaust valve or check valve can improve the response speed to a sudden rise in secondary pressure.

Further, in the case where the variable diaphragm is used as the diaphragm, the response speed of switching from the control by the first diaphragm and the second diaphragm to the control by the first diaphragm and the third diaphragm can be adjusted.

In the case where a tank communicating with the adjusting pressure chamber is provided to increase the actual volume of the adjusting pressure chamber, the control by the first diaphragm and the second diaphragm is switched to the control by the first diaphragm and the third diaphragm. The response speed can be adjusted.

The pilot type gas governor of the present invention can prevent a decrease in the secondary pressure without impairing the stability of the control even when the amount of gas used on the secondary side increases by the control by the pilot governor of the present invention. ..

It is sectional drawing which shows the basic structure of the pilot governor of this invention simplified. It is explanatory drawing of the pressure acting on the diaphragm of the pilot governor of FIG. 1 in a transitional period. It is explanatory drawing of the pressure acting on the diaphragm of the pilot governor of FIG. 1 in the stable period. It is sectional drawing which simplifies and shows an example of the pilot type gas governor of this invention using the pilot governor of FIG. It is a graph which shows the dynamic characteristic of the pilot type gas governor of FIG. It is a graph which shows the static characteristic of the pilot type gas governor of FIG. It is sectional drawing which shows the one form of the pilot governor of this invention simplified. It is sectional drawing which simplifies and shows the main part of the other form of the pilot governor of this invention. It is sectional drawing which shows the state which the exhaust valve provided in the pilot governor of FIG. 8 opens, and the adjustment pressure chamber and the drive pressure chamber communicate with each other. It is sectional drawing which simplifies and shows the main part of the other form of the pilot governor of this invention. It is sectional drawing which simplifies and shows the main part of the other form of the pilot governor of this invention. It is sectional drawing which shows the other example of the pilot type gas governor of this invention simplified. It is sectional drawing which shows the example of the conventional pilot type gas governor simplified. It is explanatory drawing of the operating state of the pilot governor adopted in the conventional pilot type gas governor. It is a graph which shows the static characteristic of the pilot type gas governor of FIG. It is a graph which shows the dynamic characteristic when the difference of the pressure receiving state of the 1st and 2nd diaphragm of the conventional pilot type gas governor is small. It is a graph which shows the dynamic characteristic when the difference of the pressure receiving state of the 1st and 2nd diaphragm of the conventional pilot type gas governor is large.

Hereinafter, an embodiment of the pilot governor of the present invention and the pilot type gas governor using the pilot governor will be described with reference to FIGS. 1 to 12 of the accompanying drawings.

FIG. 1 shows the basic configuration of the pilot governor of the present invention. The pilot governor 1 includes a casing 2, a first diaphragm 3, a second diaphragm 4, a holder 5, a drive pressure chamber 6, a secondary pressure chamber 7, an atmospheric pressure chamber 8, each of which is formed inside the casing 2, and for control. A pressure fluid introduction passage 9, a supply valve (supply valve) 10, an exhaust valve (exhaust valve) 11, a spring 12, and a pressure adjusting mechanism 13 are provided, and further, a third diaphragm 14, an adjusting pressure chamber 15, and a passage 16. , It is provided with a throttle (orifice) 17.

The casing 2 has a port Po1 connected to the loading pressure chamber of the main governor, a port Po2 connected to the balance pressure chamber of the main governor, and a port Po3 to introduce a secondary pressure regulated by the main governor. Ports Po2 and Po3 may be one in which one port is branched.

The inner peripheral side of the first to third diaphragms 3, 4, and 14 is fixed to the holder 5, and the outer peripheral side is held by the casing 2. The holder 5 can move up and down in the casing 2. The inner peripheral side of these diaphragms is reinforced by a diaphragm plate (not shown).

The holder 5 is provided by connecting the support plates 5a and 5b arranged in parallel via a plurality of bridges 5c, and further hanging a connecting shaft 5e having a flange 5d at the center of the lower surface of the support plate 5b. It has become.

The drive pressure chamber 6 and the secondary pressure chamber 7 are partitioned by a first diaphragm 3. Further, the driving pressure chamber 6 and the adjusting pressure chamber 15 are partitioned by a second diaphragm 4, and the adjusting pressure chamber 15 and the atmospheric pressure chamber 8 are partitioned by a third diaphragm 14.

The introduction passage 9 is connected to the primary side pipeline of the gas supply path and introduces the primary pressure into the drive pressure chamber 6 through the supply valve 10.

The supply valve 10 is a combination of a nozzle 10a for fixing the position of the upward opening arranged inside the drive pressure chamber 6 and a seat packing 10b for contacting and separating from the nozzle 10a.

When the pressures of the drive pressure chamber 6 and the adjustment pressure chamber 15 are equal and the forces applied to the holder 5 are balanced, the valve portion of the supply valve 10 has an opening of zero (valve closed state). Or, the seat packing 10b is separated from the nozzle 10a by a certain amount to maintain a constant opening.

The force acting and balancing against the holder 5 contradicts the force generated by the first diaphragm 3 receiving the secondary pressure, the force of the spring 12, and the first diaphragm 3 and the third diaphragm 14. It is a force applied in the direction.

The exhaust valve 11 is a valve that switches the communication state between the drive pressure chamber 6 and the secondary pressure chamber 7, and includes a valve body (rod valve) 11a incorporated in the holder 5 and a valve seat 11b provided in the holder 5. , The valve body 11a is urged in the valve closing direction (not shown. If the valve body 11a is closed by its own weight, this spring can be omitted).

The seat packing 10b of the supply valve 10 is attached to the valve body 11a of the exhaust valve 11, and the exhaust valve 11 opens in conjunction with the valve closing operation of the supply valve 10. By opening the valve, the drive pressure chamber 6 communicates with the secondary pressure chamber 7.

The spring 12 is incorporated in the atmospheric pressure chamber 8. The elastic force of the spring 12 is adjusted by the pressure adjusting mechanism 13. The pressure adjusting mechanism 13 has an adjusting bolt 13a with a handle screwed into the casing 2 and a spring presser 13b, and the spring presser 13b is moved in the axial direction by the adjusting bolt 13a to advance and retreat the spring presser 13b in the axial direction to provide a secondary pressure chamber by the spring 12. The force with the holder on the side of 7 is increased or decreased.

The difference between the pressure receiving states of the first diaphragm 3 and the second diaphragm 4 is set large. Due to the difference in the pressure receiving state, the force that the second diaphragm 4 receives the pressure of the drive pressure chamber 6 and pushes the holder 5 toward the atmospheric pressure chamber 8 is the force that the first diaphragm 3 receives the pressure of the drive pressure chamber 6 and the holder 5 Is superior to the force pushing the secondary pressure chamber 7 side.

The difference in the pressure receiving state between the first diaphragm 3 and the second diaphragm 4 can be caused by changing the design shape and mounting position of those diaphragms.

The pressure receiving states of the first diaphragm 3 and the third diaphragm 14 are similar to each other.
Therefore, when the internal pressures of the drive pressure chamber 6 and the adjustment pressure chamber 15 are equal, the force of the first diaphragm 3 pushing the holder 5 toward the secondary pressure chamber 7 and the third diaphragm 14 pushing the holder 5 toward the atmospheric pressure chamber 8 side. The pushing force is offset.

The passage 16 is provided between the driving pressure chamber 6 and the adjusting pressure chamber 15, and a throttle 17 is installed in the middle of the passage 16.

FIG. 4 shows an example of a pilot type gas governor using the pilot governor 1 configured as described above. The pilot type gas governor 30 in the figure is composed of a main governor 33 and a pilot governor 1, and the operation of the main governor 33 is controlled by the pilot governor 1.

The main governor 33 includes an on-off valve 33a for switching the communication state between the primary side pipeline 31 and the secondary side pipeline 32, a balance pressure chamber 33b, and a loading pressure chamber 33d partitioned from the balance pressure chamber 33b by the diaphragm 33c. The on-off valve 33a is provided with a main spring 33e that applies a valve closing force.

The drive pressure chamber 6 of the pilot governor 1 is connected to the primary side pipeline 31 of the gas supply path and the loading pressure chamber (drive pressure chamber) 33d of the main governor 33 via the introduction passage 9, respectively, and the secondary pressure chamber 7 is connected to the secondary pressure chamber 7. , It is connected to the secondary side pipeline 32 and the balance pressure chamber 33b of the main governor 33. Further, the adjusting pressure chamber 15 is connected to the driving pressure chamber 6 via the passage 16.

The loading pressure chamber 33d of the main governor 33 is also connected to the secondary side pipeline 32 via the passage including the orifice 34.

As described above, in this pilot type gas governor 30, when the gas in the secondary side pipeline 32 is used and the secondary pressure P2 (see FIG. 2) drops, the pressure in the secondary pressure chamber 7 of the pilot governor 1 is reduced. Decreases.

Therefore, the first to third diaphragms 3, 4, and 14 are pushed toward the secondary pressure chamber 7 side together with the holder 5 by the force of the spring 12, and the valve portion opening degree of the supply valve 10 is increased.

As a result, the amount of primary pressure introduced into the drive pressure chamber 6 increases, the pressure PW of the drive pressure chamber 6 shown in FIG. 2 increases, and the force pushing the second diaphragm 4 toward the atmospheric pressure chamber 8 increases.

At this time, the force that the second diaphragm 4 receives the pressure PC of the adjusting pressure chamber 15 and tries to move the holder 5 toward the secondary pressure chamber 7 is the force that the third diaphragm 14 receives the pressure PC and causes the holder 5 to have an atmospheric pressure. Although it is larger than the force to move to the chamber 8 side, the pressure of the adjusting pressure chamber 15 is lower than the pressure of the driving pressure chamber 6 at the beginning of control, so the force to push the holder 5 to the atmospheric pressure chamber 8 side is two. It is superior to the force pushing toward the next pressure chamber 7.

As a result, the first to third diaphragms 3, 4, and 14 move downward with the holder 5, and the holder 5 is returned to the balance point of the force received against each diaphragm, and the valve portion of the supply valve 10 is returned. The opening becomes smaller.

Further, during this period, the pressure of the drive pressure chamber 6 gradually flows into the adjustment pressure chamber 15 through the passage 16 in which the throttle 17 is arranged, and the pressure PW of the drive pressure chamber 6 and the pressure of the adjustment pressure chamber 15 shown in FIG. The pressure of the PC becomes the same (PW = PC).

In that situation, the forces applied to both sides of the second diaphragm 4 are canceled out and become zero, so that the position of the holder 5 is controlled by the first diaphragm 3 and the third diaphragm 14 in which the pressure receiving state is approximated. It will be.

As described above, in the pilot type gas governor 30 of the present invention, the position control of the holder 5 (that is, the opening control of the supply valve 10) is the difference in the pressure receiving state during the transition period (at the beginning of the control by the pilot governor 1). It is dominated by the first diaphragm 3 and the second diaphragm 4 having a large size, and is made by the first diaphragm 3 and the third diaphragm 14 having an approximate pressure receiving state in the stable period after a sufficient time has passed.

As a result, as shown in FIG. 5, there is a fluctuation of the secondary pressure P2 in the transition period, but the fluctuation is contained in the stable period, and the decrease of the secondary pressure P2 after control is suppressed to zero or extremely small. A stable secondary pressure P2 is maintained. The time from the start of control to the stable period is an adjustable time until the drive pressure chamber 6 and the adjusting pressure chamber 15 have the same pressure.

As already mentioned, the problem of the decrease in secondary pressure due to the increase in gas usage on the secondary side becomes particularly prominent in the gas supply path of applications where a large amount of gas is used.

Therefore, the pilot governor of the present invention can be widely used from those that use a large amount of gas to those that use abrupt gas.

FIG. 7 is an example of a preferred form of the pilot governor of the present invention. The pilot governor 1 of FIG. 7 has an additional mounting position adjusting mechanism 18 so that the mounting position of the third diaphragm 14 with respect to the holder 5 can be changed.

As shown in FIG. 7, the flange 5d to which the third diaphragm 14 of the holder 5 is fixed is independent from the main body of the holder 5. Further, the portion corresponding to the connecting shaft 5e is composed of a small diameter shaft portion e _-1 and a tubular large diameter shaft portion e _-2 into which the small diameter shaft portion e _-1 is slidably inserted. _-1 is provided on the support plate 5b, and the large-diameter shaft portion e _-2 is provided on the flange 5d.

Further, the adjusting screw 18a is attached to the flange 5d so that it can rotate and cannot move relative to the axial direction. The adjusting screw 18a has a rotation operation portion (not shown) such as a hexagonal hole at the lower end, and a male screw 18b formed on the outer periphery of the tip of the adjusting screw 18a is formed on the hole surface of the small diameter shaft portion e _-1 . The position adjusting mechanism 18 of the third diaphragm 14 is configured by being screwed into the female screw 18c.

The pressure receiving state of the diaphragm can be changed by changing the mounting position, and by changing the screwing amount of the adjusting screw 18a with respect to the small diameter shaft portion e _-1 , the mounting position of the third diaphragm 14 (first, second). The positional relationship with the diaphragm) fluctuates and the pressure receiving state changes. Therefore, the pilot governor 1 of FIG. 7 can adjust the pressure receiving state of the third diaphragm 14.

The pilot governor 1 may have individual differences in the response characteristics of the product due to manufacturing reasons, and the deviation of the individual differences in the response characteristics can be corrected by the mounting position adjusting mechanism 18.

FIG. 8 also shows a preferred embodiment of the pilot governor of the present invention. The pilot governor 1 of FIG. 8 is provided with an exhaust valve 19 between the drive pressure chamber 6 and the adjustment pressure chamber 15. The exhaust valve 19 is a general exhaust valve in which a valve body 19a, a valve seat 19b, and a spring 19c that urges the valve body 19a in the valve closing direction are combined.

The exhaust valve 19 is provided between the drive pressure chamber 6 and the adjustment pressure chamber 15 as shown in FIG. 9 when the pressure PW of the drive pressure chamber 6 and the pressure PC of the adjustment pressure chamber 15 become PW <PC. The valve is opened to release the pressure of the adjusting pressure chamber 15 to the driving pressure chamber 6.

The pressure PW of the drive pressure chamber 6 and the pressure PC of the adjustment pressure chamber 15 usually maintain the relationship of PW ≧ PC, but when the amount of gas used on the secondary side decreases sharply, PW <PC. May become.

The exhaust valve 19 senses the reverse pressure at this time and opens the valve (closes when the relationship of PW ≧ PC is established), and releases the pressure PC of the adjusting pressure chamber 15 to the drive pressure chamber 6 side. This makes it possible to improve the response speed to a sudden increase in the secondary pressure.

As shown in FIG. 10, a check valve 20 provided in place of the exhaust valve between the adjusting pressure chamber 15 and the driving pressure chamber 6 can be expected to have the same operation and effect.

In FIG. 10, the check valve 20 is incorporated in the passage 16 provided outside the casing 2, but the check valve 20 can also be attached to the flange 5d or the like and installed inside the casing 2.

As shown in FIG. 11, the diaphragm installed in the passage 16 may be a variable diaphragm 17A, and the pilot governor 1 having the variable diaphragm 17A has a response speed to a decrease in the secondary pressure P2 (swing of the secondary pressure P2). Convergence speed) can be adjusted.

In addition, as shown in FIG. 12, the response speed can also be changed by connecting the adjusting pressure chamber 15 to the tank 21 that increases the volume of the adjusting pressure chamber 15.

If the tank 21 that can increase or decrease the volume is used, the adjustment range of the response speed is widened.

1 Pilot governor 2 Casing Po1 to Po3 Port 3 1st diaphragm 4 2nd diaphragm 5 Holder 5a, 5b Support plate 5c Bridge 5d Flange 5e Connecting shaft e _-1 Small diameter shaft part e _-2 Large diameter shaft part 6 Drive pressure chamber 7 2 Next pressure chamber 8 Atmospheric pressure chamber 9 Introductory passage 10 Supply valve 10a Nozzle 10b Seat packing 11 Exhaust valve 11a Valve body 11b Valve seat 12 Spring 13 Pressure adjustment mechanism 13a Adjustment bolt 13b Spring retainer 14 Third diaphragm 15 Adjustment pressure chamber 16 Passage 17 Pressure 17A Variable pressure 18 Mounting position adjustment mechanism 18a Adjustment screw 18b Male thread 18c Female thread 19 Exhaust valve 19a Valve body 19b Valve seat 19c Spring 20 Check valve 21 Tank 30 Pilot type gas governor 31 Primary side pipeline 32 Secondary side pipeline 33 Main Governor 33a On-off valve 33b Balance pressure chamber 33c Diaphragm 33d Loading pressure chamber 33e Main spring 34 Orifice

Claims (5)

A drive pressure chamber (6) for introducing a primary pressure, a secondary pressure chamber (7) for introducing a secondary pressure regulated by a main governor (33), an atmospheric pressure chamber (8), and the drive pressure chamber (6). ) And the casing (2) having the adjusting pressure chamber (15) arranged between the atmospheric pressure chamber (8) inside.
A first diaphragm (3) that separates the drive pressure chamber (6) and the secondary pressure chamber (7), and a second diaphragm (4) that separates the drive pressure chamber (6) and the adjustment pressure chamber (15). , And a third diaphragm (14) that separates the adjusting pressure chamber (15) and the atmospheric pressure chamber (8).
A holder (5) arranged in the casing (2) and supporting the inner peripheral side of the first, second, and third diaphragms (3, 4, 14).
A supply valve (10) that increases or decreases the amount of control pressure fluid introduced from the primary side pipeline (31) to the drive pressure chamber (6) by the displacement of the holder (5).
An exhaust valve (11) that communicates the drive pressure chamber (6) with the secondary pressure chamber (7) in conjunction with the valve closing operation of the supply valve (10).
A spring (12) installed in the atmospheric pressure chamber (8) and urging the holder (5) toward the secondary pressure chamber (7).
A passage (16) connecting the driving pressure chamber (6) and the adjusting pressure chamber (15),
It has a diaphragm (17) arranged in the passage (16) and
The difference in the pressure receiving state between the first diaphragm (3) and the second diaphragm (4) is large.
The pressure receiving states of the first diaphragm (3) and the third diaphragm (14) are similar.
The valve of the supply valve (10) at a position where the force for moving the holder (5) toward the secondary pressure chamber (7) and the force for moving the holder (8) toward the atmospheric pressure chamber (8) are balanced. The part opening is maintained at zero or constant,
During the transient response to the decrease in secondary pressure, the position of the holder (5) is controlled by the first diaphragm (3) and the second diaphragm (4).
When the pressures of the driving pressure chamber (6) and the adjusting pressure chamber (15) are close to or equal to each other and stable, the position of the holder (5) is controlled by the first diaphragm (3) and the third diaphragm (14). Pilot governor
Between the driving pressure chamber (6) and the adjusting pressure chamber (15), the pressure (PW) of the driving pressure chamber (6) and the pressure (PC) of the adjusting pressure chamber (15) are PW ≧ PC. An exhaust valve (19) or a check valve (19) or a check valve that closes when there is a relationship and opens when PW <PC to release the pressure of the adjustment pressure chamber (15) to the drive pressure chamber (6). A pilot governor equipped with 20). The pilot governor according to claim 1, further comprising a mounting position adjusting mechanism (18) capable of changing the mounting position of the third diaphragm (14) with respect to the holder (5). The pilot governor according to claim 1 or 2 , wherein the diaphragm (17) is a variable diaphragm (17A). The pilot governor according to any one of claims 1 to 3 , further comprising a tank (21) communicating with the adjusting pressure chamber (15). A balance pressure chamber (33b) and a loading pressure chamber (33d) partitioned by a diaphragm (33c), an on-off valve (33a) for switching the communication state between the primary side pipeline (31) and the secondary side pipeline (32), and an on-off valve (33a). The on-off valve (33a) is provided with a main spring (33e) that applies a valve closing force, and is incorporated between the primary side pipeline (31) and the secondary side pipeline (32) to reduce the primary pressure. The main governor (33) to be sent to the secondary side and the pilot governor (1) according to any one of claims 1 to 4 are combined.
The driving pressure chamber (6) of the pilot governor (1) is connected to the primary side pipeline (31), and the secondary pressure chamber (7) is connected to the secondary side pipeline (32) and the main governor (33). ) To the balance pressure chamber (33b), respectively,
A pilot type gas governor in which the driving pressure chamber (6) is connected to the loading pressure chamber (33d) of the main governor (33).

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