JPH0345009Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention provides a diaphragm operating device in the water supply passage that automatically opens and closes the gas supply valve in response to water flow, and also provides a diaphragm actuating device upstream of the diaphragm operating device. This invention relates to a stop-off water heater equipped with a faucet for opening and closing water.

[Prior art]

This type of stop-start water heater is equipped with a diaphragm operating device 3 that is separated into a low pressure chamber 3a and a high pressure chamber 3b by a control diaphragm 3c, and the low pressure chamber 3a has a communication passage 4, as shown in FIG. The high-pressure chamber 3b communicates with the negative pressure generating part of the bench lily 2 provided in the water supply passage 1 through the vent lily 2, and the high pressure chamber 3b communicates with the upstream side of the bench lily 2 of the water supply passage 1, and changes the opening degree of the gas valve 5 according to the amount of water flow. The amount of gas supplied to the burner 7 that heats the heat exchanger 6 is controlled to keep the temperature of the hot water almost constant. However, in the conventional type, as shown in FIG. 7, the communication passage 4 opened at the upper part of the low pressure chamber 3a.

[Problem that the invention attempts to solve]

In this type of stop-start type water heater, when the faucet 8 that opens and closes the water flow is suddenly operated, the differential pressure between the low pressure chamber 3a and the high pressure chamber 3b transiently fluctuates due to the inertia of the water flow, etc. However, the gas valve 5 may open and close suddenly and widely, causing explosive combustion in the burner 7, which may cause the pilot burner to go out. The present invention attempts to solve such problems.

[Means for solving problems]

For this reason, in the stop-start type water heater according to the present invention, as shown in FIGS. 1 to 6, the heat exchanger 1
5 and a water supply passage 13 provided with a bench lily 14, and a control diaphragm 21 that separates the interior into a low pressure chamber 22 and a high pressure chamber 23, and the low pressure chamber 22 is connected to communication passages 30, 3.
A burner 18 is connected to the negative pressure generating section of the bench lily 14 via 0A and 30B, and the high pressure chamber 23 is connected to the water supply passage 13 at a portion other than the negative pressure generating section, and heats the heat exchanger 15.
a diaphragm operating device 20 that opens and closes a gas valve 50 provided in a gas passage 17 to the water supply passage; and a faucet provided in the water supply passage 13 on the upstream side of the diaphragm actuation device 20 that opens and closes water flow to the water supply passage. 40, the communication passages 30, 30A, and 30B are airtightly inserted into the low pressure chamber 22 from the upper part and open at the lower part of the low pressure chamber to form an air chamber in the low pressure chamber. 22
A is formed, and a drain plug 55 is further provided at the lower part of the low pressure chamber 22.

[Effect]

When the water faucet 40 is opened, a pressure difference is generated between the low pressure chamber 22 and the high pressure chamber 23 of the diaphragm actuating device 20 in accordance with the amount of water flowing through the water supply passage 13, and the opening degree of the gas valve 50 is controlled to control the heat exchanger. Gas is supplied to the burner 18 that heats the burner 15 in an amount corresponding to the amount of water flowing through the burner 15 . When the water flow rate is set to a large flow rate, if the faucet 40 is suddenly opened, the water flow rate increases rapidly and a large negative pressure is generated in the negative pressure generating section of the bench lily 14. This change in negative pressure transmitted to the low pressure chamber 22 is alleviated by the expansion and contraction of the air in the air chamber 22a, so the rate of change in the differential pressure between the low pressure chamber 22 and the high pressure chamber 23 is equal to the negative pressure generated in the bench lily 14. The rate of change is slower than the rate of change. When the faucet 40 is closed, the pressure difference between the low pressure chamber 22 and the high pressure chamber 23 disappears, so the gas valve 50 is opened and the burner 18 is extinguished. In this case, if the faucet 40 is suddenly closed, a large negative pressure is instantaneously generated downstream of the faucet 40, particularly downstream of the bench lily 14, due to the inertia of water flow. This instantaneous negative pressure is caused by the communication passages 30, 30A,
The pressure is transmitted to the low pressure chamber 22 via the air chamber 22a, but is relaxed by the expansion and contraction of the air in the air chamber 22a, so that the instantaneous increase in the differential pressure between the low pressure chamber 22 and the high pressure chamber 23 is small.

Furthermore, if the water drain valve 55 is removed with the water faucet 40 closed, the outside air will flow into the heat exchanger 15 and the water supply passage 1.
3 into the low pressure chamber 22 through the communication passages 30, 30A, and 30B, and the water in the low pressure chamber 22 is discharged from the mounting hole of the drain plug 55.

[Effect of idea]

As mentioned above, according to the present invention, even if the faucet of a stop-off type water heater is suddenly opened and closed, the rate of change in the differential pressure that occurs between the low pressure chamber and the high pressure chamber of the diaphragm operating device becomes gradual, and Since the increase in fuel consumption is also small, the gas valve will not open suddenly, and therefore the amount of gas supplied to the burner will not suddenly increase and cause explosive combustion, which will prevent the pilot burner from extinguishing. . Furthermore, if the air in the air chamber decreases for some reason and the above effect is reduced, the above effect can be easily restored by removing the drain plug and introducing air into the low pressure chamber from the communication path.

〔Example〕

Embodiments will be described below with reference to the accompanying drawings. In the first embodiment shown in FIGS. 1 and 2, the water supply passage 13 from the water supply inlet 13a to the hot water supply pipe 16 includes a faucet 40, a diaphragm operating device 20, a bench lily 14, a heat exchanger 15, and a hot water pipe 16. is provided. As shown in FIGS. 1 and 2, the inside of the diaphragm actuating device 20 formed between the main housing 10 and the valve housing 11 is connected to a low pressure chamber 22 by a control diaphragm 21 held between both housings 10 and 11. The high pressure chamber 23 is separated into a high pressure chamber 23, the low pressure chamber 22 is communicated with a negative pressure generating section of the bench lily 14 via a communication passage 30, and the water supply passage 13 passes through the high pressure chamber 23. As shown in FIGS. 1 and 2, in the first embodiment,
The communication pipe 31 constituting the communication passage 30 passes airtightly through the peripheral wall of the low pressure chamber 22 from the upper part, and its tip opens at the lower part of the low pressure chamber 22, and is connected to the water supply passage 13 that enters and exits the low pressure chamber 22 via the communication pipe 31. The water only accumulates in the lower part as shown in 22b, and the water in the low pressure chamber 22
An air chamber 22a is formed in most of the interior except for the lower part. A stopper 25 whose tip expands in a tapered shape is attached to the center of the control diaphragm 21 so as to protrude toward the valve housing 11, and a water stopper 40 is connected to the valve housing 11 coaxially with the stopper 25 to supply water from the water supply inlet 13a. An inlet opening 26 is provided which leads into the high pressure chamber 23 via the inlet opening 26 . A spring 2 is provided between the periphery of the opening 26 and the control diaphragm 21.
7 is interposed. This control diaphragm 21
The plug body 25 and the inlet opening 26 attached to the valve constitute a water governor that alleviates fluctuations in water flow rate when the water supply pressure fluctuates. Also, the valve housing 11
At the connection between the lower high pressure chamber 23 and the supply passage 13,
A drain plug 55 is provided which closes the communication between the low pressure chamber 22 and the high pressure chamber 23 when screwed on, and which simultaneously drains water from the low pressure chamber 22 and the high pressure chamber 23 when removed.

Gas passage 17 formed within main housing 10
is provided with a gas valve 50 that controls the amount of gas supplied to the burner 18 that heats the heat exchanger 15. The gas valve 50 consists of a gas valve seat 52 formed in the gas passage 17 coaxially with the control diaphragm 21, a gas valve body 51, and a spring 53 that urges the gas valve body 51 toward the gas valve seat 52. Valve body 5
1 is connected to the control diaphragm 21 via a rod 54. The gas valve body 51 is connected to the water supply passage 13
When water is not flowing through the water supply passage 13, the springs 53 and 27 contact the gas valve seat 52 to close the gas valve 50, and when water flows through the water supply passage 13, a low pressure chamber 22 and a high pressure chamber are formed depending on the amount of water flowing through the water supply passage 13. 23 moves against the spring 53 and the gas valve 5
It is designed to open 0.

In this embodiment, as shown in FIG.
The water faucet 40 provided between the water supply inlet 13a and the water supply inlet 13a is a diaphragm valve. Inside the valve housing 11, an inlet valve chamber 41 in which the water supply inlet 13a is opened and an outlet valve chamber 42 in which the inlet opening 26 is provided are formed by a cylindrical partition wall 11a formed coaxially with the inlet opening 26. ing. Also valve housing 1
1 has both valve chambers 4 on the side opposite to the main housing 10.
A cover 12 is provided to cover the valve housing 11 and the cover 12, and a partition wall 11a is provided between the valve housing 11 and the cover 12.
A faucet diaphragm 44 having an annular thick wall portion 44a that can come into contact with and separate from the entire circumference of the tip of the faucet diaphragm 44 is sandwiched between the faucet diaphragm 44 and the cover 12, and a control chamber 43 is formed between the faucet diaphragm 44 and the cover 12. At the center of the faucet diaphragm 44 is a control hole 46 that communicates the outlet valve chamber 42 and the control chamber 43.
A reinforcing metal fitting 46 is provided, and the reinforcing metal fitting 46 and the faucet diaphragm 44 are provided with an inlet valve chamber 41.
A small hole 47 that communicates with the control chamber 43 is provided.

A pilot valve 48 is supported on the cover 12 so as to be able to slide coaxially with the faucet diaphragm 44 through a rod 48b.
Open and close 6a. The pilot valve 48 is biased toward the reinforcing metal fitting 46 by a weak spring 49 provided between it and the cover 12, and the sealing material 48
When the control hole 46a is closed by the spring 49, the faucet diaphragm 44
Once the thick portion 44a of the partition wall 11a comes into contact with the tip of the partition wall 11a, the pressure in the control chamber 43 becomes equal to the pressure in the inlet valve chamber 41 through the small hole 47, that is, the water supply pressure, while the pressure in the outlet valve chamber 42 becomes equal to Since the pressure becomes atmospheric pressure, the thick wall portion 44a is affected by the partition wall 11 due to this pressure difference.
The water flow is reliably stopped by being pressed by the tip of a, and the faucet 40 is closed. If the pilot valve 48 is manually pulled to the right against the weak spring 49 using a knob or lever, the control hole 46 is opened.
a is opened and the pressure in the control chamber 43 becomes equal to the pressure (atmospheric pressure) in the outlet valve chamber 42.
3 side, the thick portion 44a is separated from the tip of the partition wall 11a, and the faucet 40 is in an open state. If the faucet 40 is a diaphragm valve as in this embodiment, the operating force of the faucet 40 will be reduced and the operation will be easier. May be used.

When the faucet 40 is open, the water supply passage 1
The amount of water flowing in step 3 changes by changing the opening degree of the hot water tap (not shown). When the amount of water passing increases, the opening degree of the gas valve 50 is also increased by the diaphragm operating device 20, and an amount of gas corresponding to the amount of water passing is supplied to the burner 18 and heating the heat exchanger 15, so the amount of water passing changes. However, the hot water temperature is maintained at a predetermined value.
In addition, although the adjustment device for the tapping temperature is omitted in this embodiment, a known temperature adjustment device may be provided if necessary.

When the opening of the hot water faucet is opened to set a large water flow rate, if the faucet 40 is suddenly opened, the water flow rate increases rapidly, and a large negative pressure is suddenly generated in the negative pressure generating portion of the bench lily 14. . This negative pressure
1 into the low pressure chamber 22, but the air chamber 2
The rate of change in pressure is moderated by the expansion and contraction of the air in 2a, and the opening degree of the gas valve 50 changes gradually, so the amount of gas supplied to the burner 18 increases gradually, and explosive combustion does not occur. . When the faucet 40 is closed to stop water flowing through the water supply passage 13, the gas valve 50 is closed by the action of the springs 53 and 27, and the burner 18 is extinguished. In this case, if the faucet 40 is suddenly closed, a negative pressure is instantaneously generated on the downstream side of the faucet 40 due to the inertia of water flow. This negative pressure becomes especially large downstream of the vent lily 14, which acts as a restrictor, and is transmitted to the low pressure chamber 22 via the communication pipe 31, but is relieved by the expansion and contraction of the air in the air chamber 22a. The instantaneous increase in the opening degree of the gas valve 50 is small, and explosive combustion does not occur.

Furthermore, if for some reason the air in the low pressure chamber 22 escapes and the volume of the air chamber 22a decreases, the above-mentioned effect will not be achieved satisfactorily. In such a case, if you open the hot water tap (not shown) at the tip of the hot water supply pipe 16 with the faucet 40 closed and remove the water drain valve 55, external air will enter from the hot water pipe 16 and the heat exchanger 15, water in the water supply passage 13, high pressure chamber 23 and outlet valve chamber 42 is discharged from the mounting hole of the drain valve 55;
In addition, air in the water supply passage 13 passes from the bench lily 14 through the communication passages 30, 30A, and 30B to the low pressure chamber 22.
The water introduced into the low pressure chamber 22 is also discharged from the mounting hole of the drain plug 55. This allows the above-mentioned effect to be easily restored.

The second embodiment, in which only the different parts are shown in FIGS. 3 and 4, differs from the communication path 30 of the first embodiment only in the structure of the communication path 30A. As shown in FIG. 4, the distal end 32A of the communication passage 30A has an Ω cross-sectional shape, and both side edges are fixed to the inner wall of the low pressure chamber 22 by brazing or the like, and its lower end is opened at the lower part of the low pressure chamber 22. , its upper end is communicated with the negative pressure generating portion of the bench lily 14 through a communication pipe 31A that passes through the peripheral wall of the low pressure chamber 22 in an airtight manner.

Further, in the third embodiment, only the different parts are shown in FIGS. 5 and 6, the only difference is the structure of the communication passage 30B from the communication passages 30, 30A of the first and second embodiments. The tip of the communication path 30B is formed by a partition wall 32B brazed to the inner wall of the low pressure chamber 22,
Its lower edge opens into the lower part of the low pressure chamber 22, and its upper part communicates with the negative pressure generating section of the bench lily 14 through a communication pipe 31B, as in the second embodiment.

[Brief explanation of the drawing]

Figures 1 to 6 show embodiments of the present invention, Figure 1 is a structural diagram showing the main parts of the first embodiment cut away, Figure 2 is a sectional view taken from Figure 1, and Figure 3 is a cross-sectional view of the main part of the first embodiment. A cross-sectional view showing differences between the second embodiment and the first embodiment.
The figure is a cross-sectional view of FIG. 3, FIG. 5 is a cross-sectional view showing different parts of the third embodiment, and FIG. 6 is a cross-sectional view of FIG.
The sectional view, FIG. 7, is a diagram corresponding to FIG. 1 of the conventional example. Explanation of symbols, 13... Water supply passage, 14... Bench lily, 15... Heat exchanger, 17... Gas passage,
18...Burner, 20...Diaphragm actuator, 21...Control diaphragm, 22...Low pressure chamber, 22a...Air chamber, 23...High pressure chamber, 30,
30A, 30B...Communication path, 40...Water faucet, 55
...Drain tap.

Claims (1)

[Scope of utility model registration request] The interior is separated into a low pressure chamber and a high pressure chamber by a water supply passage provided with a heat exchanger and a bench lily, and a control diaphragm. a diaphragm operating device that opens and closes a gas valve provided in a gas passage to a burner that communicates with the water supply passage and heats the heat exchanger in a portion other than the pressure generating section; In a stop-start type gas water heater that is provided with a water faucet installed in a passageway to open and close water flow to the water supply passageway, the communication passageway is airtightly inserted into the low-pressure chamber from the upper part and at the lower part of the low-pressure chamber. What is claimed is: 1. A stop-off type gas water heater, characterized in that an air chamber is opened in the low pressure chamber, and a drain plug is provided at the bottom of the low pressure chamber.