JPH0138463Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention mainly relates to a water pressure responsive valve device in an instantaneous gas water heater.

Conventionally, this type of device includes an on-off valve that responds to a diaphragm having a pressure chamber on the front that is interposed in a water passage leading to the heat exchanger, in a gas passage leading to a gas burner that heats the heat exchanger, and A type is known in which a restrictor tube 8 is provided on the downstream side of the diaphragm in series with the pressure chamber to intervene in the water passage and throttle the water passage 4, but such a type prevents freezing in cold weather. It is considered to drain water as much as possible,
In this case, since the outlet at the lower end of the throttle tube has a relatively small diameter, the last water droplets adhere to the inside and create a water pool, which freezes and tends to block the outlet. When water is passed through the heat exchanger for reuse, the frozen water block blocks the passage of water, and water does not pass through the heat exchanger downstream thereof, resulting in the inconvenience that dry water is likely to occur in the heat exchanger. . To explain further, the throttle tube is, for example, as shown by a in FIG. becomes a blockage state.

The purpose of the present invention is to obtain a device free of such inconveniences, and the gas passage 3 leading to the gas burner 2 that heats the heat exchanger 1 and the water passage 4 leading to the heat exchanger 1 are connected to each other. An on-off valve 7 responsive to a diaphragm 6 having a pressure chamber 5 on the rear side is intervened, and an on-off valve 7 is inserted in the water passage 4 in series with the pressure chamber 5 on the downstream side of the diaphragm 6 to open the water passage. 4
In this type, the throttle tube 8 is provided with an opening 12 on the side that bypasses a water pool 11 formed at the outlet 10 at the lower end of the throttle tube 8.

In the illustrated embodiment, a negative pressure chamber 9 is provided on the back surface of the diaphragm 6, and the negative pressure chamber 9 is communicated with the negative pressure generating portion of the throttle tube 8, thereby further enhancing the responsiveness of the diaphragm 6.

Figures 2 and 3 show one example.
Reference numeral 3 indicates a water drain plug interposed in the water passage 4, and reference numeral 14 indicates a hot water tap on the downstream side of the heat exchanger 1. In this case, as clearly shown in FIG. 3, the side opening 12 is formed as a relatively large-diameter through hole in the upper wall of the water reservoir 11, and is formed on one side of the water reservoir 11. A side road was created. The opening 12 is not limited to this, and may have a shape as shown in FIG. 4 or 5, for example.

To explain its operation, consider a situation in which water droplets in the outlet 10 at the lower end of the throttle tube 8 adhere and freeze during the water draining operation, and the outlet 10 is thus blocked. When the water is opened, the water guided through the water passage 4 is guided from the inside of the throttle pipe 8 to the downstream side through the side opening 12, and the inside of the heat exchanger 1 is in a state where water is supplied. Therefore, no dry boiling occurs, and upon subsequent operation, the water reservoir 11 is thawed and the outlet 10 is opened, allowing normal operation.

In this way, according to the present invention, the throttle tube 8 is provided with an opening 12 on the side that bypasses the water pool 11 formed in the outlet 10 at the lower end of the throttle pipe 8, so that water droplets do not form in the water pool 11 when draining water. Even if the outflow port 10 is blocked due to adhesion and freezing, the constriction pipe 8 can guide the water through the bypass opening 12 when water is passed through for reuse. This has the effect of eliminating the above-mentioned disadvantages of conventional methods that prevent the passage of water.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of a conventional example, Fig. 2 is a partially cut-away side view of an example of the present device, Fig. 3 is an enlarged cut-away side view of its main parts, Figs. The figure is a cutaway side view of each modification. DESCRIPTION OF SYMBOLS 1... Heat exchanger, 2... Gas burner, 3... Gas passage, 4... Water passage, 5... Pressure chamber, 6... Diaphragm, 7... Opening/closing valve, 8... Throttle pipe, 9...
...Negative pressure chamber, 10...Outlet, 11...Water pool,
12...Opening.

Claims (1)

[Scope of utility model registration request] A gas passage 3 leading to a gas burner 2 that heats the heat exchanger 1 is provided with an on-off valve 7 that responds to a diaphragm 6 having a pressure chamber 5 on the front surface interposed in a water passage 4 leading to the heat exchanger 1. At the same time, in a type that is provided with a throttle pipe 8 that intervenes in the water passage 4 in series with the pressure chamber 5 and throttles the water passage 4 on the downstream side of the diaphragm 6, the throttle pipe 8 has a lower end thereof. A water pressure responsive valve device for a water heater, comprising a side opening 12 that bypasses a water pool 11 generated at an outlet 10.