JPH0361203B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a water control device used in gas instantaneous water heaters, oil water heaters, etc., which functions to control and detect the amount of water. It is characterized in that the opening degree of the valve interlocked with the diaphragm is adjusted by controlling the pressure difference between the chamber and the secondary pressure chamber with a regulating valve. Conventionally,
A control device is used in which a control valve is installed in the water flow path and the pressure difference before and after the valve is applied to a diaphragm, but because the control valve is inserted directly into the flow path, the size of the control valve increases. It also required a lot of power to operate it. In addition, as another example, a passage upstream of a main valve that is interlocked with a diaphragm and a passage downstream of the main valve are each communicated with the back pressure side of the diaphragm, and a control valve provided in the communication section controls the pressure on the back pressure side. A method is also known in which the opening degree of the main valve linked to the diaphragm is controlled by changing the opening degree of the main valve. This method requires less operating force to move the control valve, but with this configuration, changes in the supply pressure on the upstream side are directly reflected in pressure changes on the back pressure side of the diaphragm, so the flow rate can be stabilized even if the supply pressure changes. There was no governor effect. Additionally, there was a limit to the maximum amount of water that could flow due to pressure loss in the control valve.

The present invention does not require a control valve to be inserted into the water flow path.
This system directly controls the amount of water, and aims to reduce the size and shape and reduce the force required for operation, while also stabilizing the amount of water flowing through water heating equipment regardless of fluctuations in water supply pressure. It is said that

A more detailed explanation will be given below based on figures showing examples.

FIG. 1 is a block diagram of a gas instantaneous water heater including a cross-sectional view of a water control device. 1 is a water control device in which water enters the chamber 4 through an inlet 3 forming part of the inflow path 2; A control hole 5 is opened above the chamber 4, from which water flows into the primary pressure chamber 6, and then flows through the outflow path 7.
It flows away through a ventilated tube-shaped constriction 8 which forms part of the . 9 is a valve corresponding to the control hole 5;
It is attached so as to interlock with the diaphragm 10 on the upper surface of the secondary pressure chamber 6. The other surface of the diaphragm 10 faces the secondary pressure chamber 11, and is always urged toward the primary pressure chamber 6 by a spring 12 in the secondary pressure chamber 11. The diaphragm 10 can move up and down, and the movement is transmitted to the outside by the shaft 13.

Next, there is a first communication passage 14 connecting the primary pressure chamber 6 and the secondary pressure chamber 11, and an opening 15 on the primary pressure chamber 6 side.
and a control valve 17 in the middle of the opening 16 on the side of the secondary pressure chamber 11.
is provided. This control valve 17 has a knob 18
The water flow resistance of the first communication path 14 can be changed by rotating it and moving from side to side in the figure.
A second communication path 14 is located at a substantially symmetrical position with respect to the first communication path 14.
There is a communication path 19. This connects an opening 20 provided in the throttle section 8 in the outflow path 7 and an opening 21 provided in the secondary pressure chamber 11.

There is a heat exchanger 22 in the outflow path 7, and hot water is supplied to a hot water faucet (not shown).

On the other hand, fuel gas enters the gas tank 24 through the gas passage 23. After this, pilot passage 25
In parallel with the circuit going from to the pilot burner 26,
There is a circuit going from the main passage 27 to the main burner 28 .
A response valve 29 that opens and closes according to the movement of the shaft 13 of the water control device 1 is provided in the middle of the main passage 27 . In addition, although not shown, an ignition device and an ignition detection device are provided.

Operate the gas tank 24 to turn on the pilot burner 2.
6 and after confirming that it has ignited, gas is supplied to the main passage 27. For the reasons mentioned below,
When water flows, the response valve 29 opens and the main burner 28 burns the water, making it possible to obtain hot water.

Now, the operation of the water control device will be explained using the operation explanatory diagram of FIG. 2. FIG. 2A shows the relationship between water volume and diaphragm differential pressure. As the amount of water increases, the pressure difference between the throttle section 8 and the primary pressure chamber 6 increases almost in a square relationship. Here, A is the control valve 1
7 indicates a fully closed state. The valve 17 is gradually opened in steps B and C, and D indicates the fully open state. The state A, in which the control valve 17 is fully closed, is the same state as if the first communication passage 14 is not present, and the diaphragm differential pressure is equal to the pressure difference occurring at the constricted portion. However, the control valve 17
If it is opened even slightly, a waterway called the secondary pressure chamber 11 and the second communication passage 19 is formed from the first communication passage 14, and the opening 15 of the first communication passage 14 and the opening 20 of the second communication passage are connected. During this time, a pressure difference at the constriction section is added. As a result, the pressure in the secondary pressure chamber 11 of the diaphragm 10 becomes a value obtained by dividing the pressure difference in the ventilate tube by the resistance ratio of the first communication passage 14 and the resistance ratio of the second communication passage 19, so the control valve 17 is opened. Accordingly, even if the amount of water is the same, the differential pressure acting on the diaphragm 10 will decrease. Next, FIG. 2B shows the force of the diaphragm 10 generated by the differential pressure acting on the diaphragm 10 and the opening degree of the valve 9. When the force of the diaphragm 10 becomes strong enough to overcome the set load of the spring 12, the valve opening gradually becomes narrower, and at the same time, the water flow pressure drop when passing through the valve 9 increases. As is well known, as the valve opening decreases, an exponential pressure drop will occur.

Now, assuming that the opening degree of the control valve 17 is in the state B, the diaphragm differential pressure becomes ΔP ₂ at the water volume W ₂ , which acts on the area of the diaphragm 10.
A force called F ₂ is generated. This F ₂ force and spring 1
The valve opening at which the repulsive forces of 2 are balanced is q ₂ . In this state, assuming that the water pressure applied to the inlet 3 increases, the amount of water tends to increase, but as a result, the valve opening degree q ₂ tends to decrease by a very small amount. This decrease in valve opening acts to rapidly increase the pressure loss in this part, so the increase in inlet water pressure is almost consumed in the valve 9 part, and as a result, the water volume value of W ₂ is almost maintained. be able to. This is the well-known governor effect. That is, if the opening degree of the control valve 17 is B, it functions to maintain the water amount _W2 . Similarly, if the opening degree of the control valve is set to C, the water volume _W3 becomes
If the opening degree is set to 2, it works to maintain the water volume W ₄ . As the opening degree of the control valve 17 is set to increase the amount of water, the opening degree of the valve 9 becomes wider.
This is because as the amount of water increases, the pressure loss rapidly increases even when the opening is wide, and the so-called governor effect is exhibited.

As described above, by changing the opening degree of the control valve 17, it is possible to change the water amount value that the governor attempts to maintain.

The water flow rate is controlled by changing the differential pressure that directly acts on the diaphragm 10 without inserting the regulating valve 17 into the passage where water mainly flows. In order to stabilize the water flow resistance of the communication path 19, the method shown in the partial sectional view of FIG. 3 is effective. Here, the second communication path 1
Orifice 30 was inserted in the middle of 9. If the orifice diameter is large, the amount of water is maintained small even with the same opening degree of the control valve 17, so the first communication passage 14 and the control valve 1
The diameter of the orifice 30 is preferably small in order to configure the orifice 7 to be small and to secure a large amount of water that can flow to the maximum value. If it becomes too small, there will be a delay in response to sudden changes in water pressure, so it is necessary to find the optimum design value.

The position of the diaphragm 10 is determined by its force and the repulsive force of the spring 12, which not only moves the valve 9 but also moves the shaft 13 up and down at the same time. Therefore, the responsive valve 29 may be pushed open directly by the shaft 13 mechanically, or the responsive valve 29 (in this case, a solenoid valve) may be opened electrically via a micro switch. That is, it also functions as a water amount detector that detects the amount of water and causes gas combustion.

Now, the height relationship between the opening 15 where the first communication passage 14 connects to the primary pressure chamber and the opening 20 where the second communication passage 19 connects to the constriction part 8 in the outflow path 7 is changed in the installed state. It's good to leave it there. This is to completely drain water to prevent freezing. Although not shown, a drain plug is provided in the inlet 3 and the outflow path after passing through the heat exchanger 22. When these spigots are opened, water drains from the lower spigot and air enters from the higher spigot. However, conventionally, the secondary pressure chamber 11 was connected only through one communication passage (the second communication passage 19 in FIG. 1), so water and air could not be replaced by surface tension. I can't do it, 2
The water in the subpressure chamber 11 was difficult to drain. However, according to the present invention, the two communicating paths 14, 19
Therefore, if the height relationship between the opening 15 and the opening 20 facing the primary pressure chamber 15 and the throttle section 8, which are first replaced with air when water is drained, is configured to be changed, the water can be drained extremely quickly. Can be removed. In the case shown, air enters through the opening 15, drains through the opening 20, and the water is discharged to the outside through the drain plug. Furthermore, if the two communicating passages 14 and 19 are arranged symmetrically with respect to the center of the secondary pressure chamber 11, water can be drained more completely.

In FIG. 1, the control valve 17 is provided on the first communication path 14 side, but it may be provided on the second communication path 19 side. In this case, as the opening of the control valve is increased, the pressure in the secondary pressure chamber 11 approaches the pressure in the constriction section 8, so the differential pressure increases and the water amount value decreases. That is, the effect is opposite to that described in FIG.

As explained above, since this is a method that indirectly controls the differential pressure of the diaphragm that acts as a governor without changing the resistance value of the main flow channel, the control valve for changing the water volume can be downsized, and the required amount of movement can be reduced. The operating force is significantly reduced, making operation easier. In addition, since the pressure acting on the diaphragm is configured to show a value corresponding to the water flow rate, the water flow rate is stabilized even when the supply water pressure changes. It is also possible to stabilize the water temperature. Furthermore, water removal performance is improved, eliminating damage caused by freezing and unusable conditions.

In addition, since the drive pressure for water flow control uses the pressure generated by its own water flow, rather than relying on external power such as a pump, the device can be made smaller and simpler, and malfunctions due to failure of the external power. reliability can be increased without fear of

[Brief explanation of drawings]

Fig. 1 is a configuration diagram of a gas instantaneous water heater including a sectional view of a water control device that is an embodiment of the present invention, Fig. 2 is an explanatory diagram of operation, and Fig. 3 is a water control device in another embodiment. FIG. 3 is a partial cross-sectional view of the device. 10...Diaphragm, 6...Primary pressure chamber, 11...2
Secondary pressure chamber, 5... Control hole, 9... Valve, 2... Inflow path, 7
...Outflow path, 14...First communication path, 8...Low pressure section, ventilate pipe, 19...Second communication path, 17...Control valve, 30...Orifice.

Claims (1)

[Scope of Claims] 1. A diaphragm, a primary pressure chamber and a secondary pressure chamber separated by the diaphragm, a control hole that serves as an inflow section from upstream to the primary pressure chamber, and a control hole opening degree that is interlocked with the diaphragm. an inflow path leading to the control hole, an outflow path exiting downstream from the primary pressure chamber, a throttle section provided in the middle thereof, and a first communication path communicating the primary pressure chamber and the secondary pressure chamber. , consists of a second communication passage that communicates the throttle part and the secondary pressure chamber, and a control valve provided in either communication passage, and the amount of inflow water can be adjusted by changing the opening degree of this control valve. Water control device that performs control. 2. The water control device according to claim 1, wherein the constriction portion is formed by a ventilate tube in the outflow path. 3. The water control device according to claim 1, characterized in that an orifice is disposed in the communication path that does not have a control valve. 4. The opening positions of the two communication passages in the secondary pressure chamber are as follows:
The water control device according to claim 1, characterized in that the secondary pressure chambers are provided substantially symmetrically. 5. Claim 1, characterized in that the position where the first communication passage opens into the primary pressure chamber and the position where the second communication passage opens into the outflow passage are provided at different heights. water control device.