JPH0419316Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a gas combustion output proportional control device used in the field of various gas appliances such as gas burners for household or industrial use.

[Prior Art] Many devices have already been devised and implemented that continuously control the flow rate of gas by adjusting the back pressure of a governor mechanism. For example, the devices shown in Japanese Patent Application Laid-Open Nos. 57-112609 and 56-80622 are equipped with a governor and a solenoid valve in the gas passage leading to the back pressure chamber. Gas output is controlled by changing back pressure.

[The problem that the idea aims to solve]

However, with such conventional equipment, the flow rate in the middle and small flow ranges of gas output is not stable, the flow rate decreases over time, and the type of gas supplied is changed (conversion from city gas to natural gas). In such cases, there was a problem in that it was not possible to respond promptly.

This invention was made in view of the problems of the conventional technology, and its purpose is to eliminate the instability of gas output in the entire flow range from maximum to intermediate and minimum. In addition, the present invention aims to provide a gas combustion output proportional device that can quickly respond to changes in the type of gas to be supplied without changing mechanical parts such as needle valves, has a simple configuration, and is advantageous in terms of cost. It is.

[Means for Solving the Problems] In order to achieve the above object, the gas combustion output proportional control device in this invention includes a bypass passage 9 branched from the gas inlet 5 so as to bypass the main valve 4.
From this bypass passage 9, the back pressure chamber 6 is passed through the solenoid valve chamber 15.
From the first passage 7 and bypass passage 9 leading to the outlet 2
A second passage 9' leading to the second passage 9' and a communication passage 21 connecting the first and second passages 7, 9' are provided,
The electromagnetic valve 8 is provided in the electromagnetic valve chamber 15 to open and close the communication passage 21, and a first governor 10 for maximum control is provided in a part of the detour passage 9. A second governor 11 for minimum control is provided in a passage 9a that branches from the next side and leads to the back pressure chamber 6, and throttle valves 17 and 18 are provided in the first and second passages 7 and 9', respectively. Throttle valves 16 and 19 are provided in each passage between the secondary side of the governor 11 and the back pressure chamber 6 and between the solenoid valve chamber 15 and the back pressure chamber 6, and the passage 21 has a hole diameter smaller than that of each throttle valve. A large orifice hole 14 is provided.

[Embodiment] The diaphragm 1 is made of an elastic body such as a rubber membrane so as to respond to gas pressure or the like, and the main valve 4 is directly attached to the center of the pressure receiving surface. Main valve 4 has valve port 3
A spring 12 biased in the direction of closing is provided, but this spring may not be provided in some cases.

The solenoid valve 8 is set to open the valve port 13 of the passage 21 when energized and close when not energized, and is provided in a solenoid valve chamber 15 formed of a cavity. This solenoid valve 8 appropriately performs two operations, energized and de-energized, on and off, and accordingly opens and closes the valve port 13. By changing the time or cycle of the on and off operations, the back pressure chamber 6 back pressure can be controlled. The gas passing through the valve port 13 exits to the outlet 12 via the orifice hole 14.

The first and second governors 10 and 11 for maximum control and minimum control are configured by providing valve bodies 10b and 11b on diaphragms 10a and 11a that respond to gas pressure, similar to the main valve 4. Springs 10c and 11c are energized.

A throttle valve 19 is provided between the solenoid valve chamber 15 and the back pressure chamber 6.
Also, a throttle valve 18 is provided in the passage 9' between the secondary side of the first governor 10 and the outlet 2, and a throttle valve 17 is further provided in the passage 7. Further, a throttle valve 16 is provided between the second governor 11 and the back pressure chamber 6. An orifice hole 14 is provided in a passage 21 that communicates the passages 7 and 9'.

The throttle valves 16 and 19 are for removing pulsations in the flow rate to the back pressure chamber 6 and providing a time delay, and the throttle valve 17 is for preventing pulsations in the electromagnetic valve chamber 15. The throttle valve 18 functions as a relief valve for the secondary side flow rate of the first governor 10 at the time of maximum flow rate. Gas enters the pressure receiving chamber 20 from the inlet 5 and from there passes through the valve port 3 of the main valve 4 to the outlet 2.
leaks to.

The secondary pressure of the first governor 10 is PL, the second governor 1
If the secondary pressure of 1 is Ps, it is set as P ₁ > PL > Ps > P ₂ (P ₁ is the gas pressure at the inlet, P ₂ is the gas pressure at the outlet), and the orifice hole 14 is a restrictor. The diameter of the hole shall be larger than that of the valve.

[Operation] When the solenoid valve 8 is on (open), the gas flowing in from the inlet 5 passes through the first and second governors 10 and 11, the throttle valves 16 and 19, and then from the solenoid valve chamber 15 to the valve port 13, One that leads to the outlet 2 through the orifice hole 14, one that leads from the first governor 10 to the outlet 2 through the passage 9, the throttle valve 17, the electromagnetic valve 8, and the orifice hole 14, and one that leads from the first governor 10 to the outlet 2 through the passage 9. 9 and 9' to the outlet 2 via the throttle valve 18 and the orifice hole 14. However, since the diameter of the orifice hole 14 is larger than that of the throttle valve, the pressure applied to the back pressure chamber 6 is The secondary pressure Ps of the second governor 11 is added and the pressure is low. Therefore, the pressing force of the diaphragm 1 is small, and the opening degree of the valve port 3 of the main valve 4 is also small, so the gas flow rate flowing through the main channel is minimized.

Next, when the solenoid valve 8 is off (closed), the inlet 5
The gas passes through the passage 9 from the first governor 10 to the back pressure chamber 6 via the throttle valves 17 and 19, and from the first and second governors 10 and 11 to the back pressure chamber 6 through the throttle valve 16. and the first governor 1
0 through the passages 9, 9', the throttle valve 18, and the orifice hole 14 to the outlet 2, but PL>Ps
Since the secondary pressure of the first governor 10 is applied to the back pressure chamber 6, a larger back pressure acts on the diaphragm 1 than before, and the valve port 3 of the main valve 4 is also opened wide, so the flow rate is Maximum.

In other words, the amount of gas can be controlled depending on the magnitude of the back pressure in the back pressure chamber 6.

In order to change the pressure in the back pressure chamber, the time or cycle of the on/off operation of the solenoid valve 8 may be changed. In other words,
In the formula Ton+Toff=T (period), when Ton is increased, the time during which the solenoid valve is open becomes relatively longer, so the pressure Pr in the back pressure chamber becomes lower.

Alternatively, if the on-time Ton of the solenoid valve 8 is kept constant and the period T is shortened, the pressure Pr in the back pressure chamber 6 can be similarly reduced.
becomes lower.

Next, the relationship between the first governor 10 and the second governor 11 is as follows: When Po≦Ps (Po is the pressure in the solenoid valve chamber 15), the second governor 11 controls the pressure in the back pressure chamber 6, and Po> When Ps, the pressure Pr in the back pressure chamber is controlled by the first governor 10, and compared to the case where the pressure in the back pressure chamber is controlled by only one governor as in the conventional technology, the pressure Pr in the back pressure chamber is controlled by the second governor 11. The main gas flow rate can be controlled stably in the operating range (low flow range).

When changing the supply gas type, the pressure P ₁ at the inlet 5 and the primary pressure of the first governor 10 change depending on the gas type, so the solenoid valve 8 is turned off (closed) and the outlet 2 is changed.
The pressure _P2 in the back pressure chamber is set by the spring 10c so that the main gas flow rate is maximized, and
Also, turn on (open) the solenoid valve 8 and set Ps to the spring 11c.
The pressure Pr in the back pressure chamber is set so that the main gas flow rate is minimized. When setting the secondary pressure Ps of the second governor 11 at this minimum flow rate, the pressure Pr in the back pressure chamber is adjusted by the spring 11c to match the pressure loss before and after the orifice hole 14 without changing the diameter of the orifice hole 14. That is, this can be done by setting the secondary pressure of the second governor 11.

[Effect of the invention] As explained above, this invention
A bypass passage 9 branched from the main valve 4 to bypass the main valve 4.
A first passage 7 leading from the detour passage 9 to the back pressure chamber 6 via the electromagnetic valve chamber 15, a second passage 9' leading from the detour passage 9 to the outlet 2, and the first and second passages. 7 and 9' is provided, and the solenoid valve 8 is provided in the solenoid valve chamber 15 to open and close the communication passage 21, and a part of the detour passage 9 is provided with a maximum control valve. 1st
A governor 10 is provided, and a second governor 11 for minimum control is provided in a passage 9a branching from the secondary side of the first governor 10 and leading to the back pressure chamber 6, and the first and second passages 7, 9' are provided with a second governor 11 for minimum control. Throttle valves 17 and 18 respectively
In addition, throttle valves 16 and 19 are provided in the passages between the secondary side of the second governor 11 and the back pressure chamber 6 and between the solenoid valve chamber 15 and the back pressure chamber 6, respectively, and the communication passage 21 is provided with throttle valves 16 and 19, respectively. Orifice hole 14 having a larger hole diameter than each of the throttle valves.
, the main gas flow rate can be adjusted from maximum to minimum.
In particular, stable control can be performed in the low flow range, and even when changing gas types, it can be easily and reliably handled by simply adjusting the secondary pressure of both governors without replacing component parts such as needle valves. It is simple, accurate in operation, durable, and inexpensive to implement.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional front view showing an embodiment of the device according to this invention. 1...Diaphragm, 2...Gas outlet, 3...
...Valve port, 4... Main valve, 5... Gas inlet, 6...
Back pressure chamber, 7... first passage, 8... solenoid valve, 9...
...Detour passage, 9'...Second passage, 10...First governor for maximum control, 11...Second governor for minimum control, 14...Orifice hole, 1
5... Solenoid valve chamber, 16, 17, 18, 19... Throttle valve, 21... Communication passage.

Claims (1)

[Scope of utility model registration request] A diaphragm 1 that is displaced depending on the relationship between gas pressure and back pressure, a main valve 4 that is connected to the diaphragm 1 to open and close a valve port 3 to the gas outlet 2, and externally controls the back pressure of the diaphragm. In a gas combustion output control device equipped with a solenoid valve 8, a solenoid valve chamber 15 is connected from the gas inlet 5 to a detour passage 9 branched to bypass the main valve 4.
A first passage 7 leading to the back pressure chamber 6 via the detour passage 9, a second passage 9' leading from the detour passage 9 to the outlet 2, and a communication passage 21 connecting the first and second passages 7 and 9'. The electromagnetic valve 8 is provided in the electromagnetic valve chamber 15 to open and close the communication passage 21, and a first governor 10 for maximum control is provided in a part of the detour passage 9. A second governor 11 for minimum control is provided in a passage 9a branching from the secondary side of the governor 10 and leading to the back pressure chamber 6, and throttle valves 17 and 18 are provided in the first and second passages 7 and 9', respectively. In addition, throttle valves 16 and 19 are provided in the passages between the secondary side of the second governor 11 and the back pressure chamber 6 and between the solenoid valve chamber 15 and the back pressure chamber 6, respectively, and the communication passage 21 is provided with throttle valves 16 and 19, respectively. A gas combustion output proportional control device comprising an orifice hole 14 having a larger hole diameter than each of the throttle valves.