JPS5914676Y2 - Antifreeze device for water heater - Google Patents

Description

[Detailed Description of the Invention] The purpose of the present invention is to automatically discharge residual water in the water circuit in response to a drop in temperature when the water heater is out of operation to prevent it from freezing.

In conventional water heaters, water is drained from the water circuit by closing the drain valve each time, thereby preventing the water circuit from freezing.

However, with systems that rely on humans to drain the water, mistakes are bound to occur. For example, if you forget to drain the water, the water circuit of the water heater may freeze, and its volumetric expansion can cause damage to the water circuit and malfunction of water equipment. I was awake.

The present invention solves the above-mentioned conventional problems by automatically opening the drain passage using a bimetal that reverses when the ambient temperature is near 0°C.An embodiment thereof will be described below with reference to the accompanying drawings.

In FIG. 1, reference numeral 1 denotes a water circuit of a water heater, and a heat exchanger 2, which is heated by a gas burner or the like, is located midway through the water circuit.

3 is a faucet, 4 is a water governor, and 5 is a water draining device, the construction of which is shown in FIG.

That is, 6 is a device main body whose upper end is connected to the water circuit 1, and a water drain passage 7 is formed in the direction of its central axis.

Reference numeral 8 indicates a valve seat provided in the middle of the valve seat, and 9 indicates a water drain valve that opens and closes the valve seat 8. The upper end surface of the drain valve is made flat so that the water pressure of the water circuit 1 can be applied effectively.

10 is a case having a drain port 11 screwed onto the lower end of the main body 6, and 12 is a dish-shaped bimetal whose periphery is held between the main body 6 and the case 10. It is reversed upward and applies an upward pressing force to the drain valve 9 through the valve rod 13.

Further, the bimetal 12 is installed outside the water heater at a location susceptible to the influence of outside temperature, and further has a plurality of water holes 14.

The water drain valve 9 is pressed in the closing direction by the pressure of the water flowing in the water circuit 1, and is pressed in the closing direction by the upward reversal of the bimetal 12. The relationship with the opening force Fo is set so that Fc>Fo.

If a sufficient closing force Fc due to water pressure cannot be obtained, a spring may be provided as an auxiliary means.

In the above configuration, FIG. 2 shows the operating state of the water heater, that is, in this case, the pressure of the water flowing through the water circuit 1 is applied in the closing direction of the drain valve 9, so the valve seat 8 is closed. .

Also, at this time, the ambient temperature is close to 0℃, and the bimetal 1
Even if 2 tries to turn upward, the drain valve 9 will not operate due to the above-described force relationship of Fc>Fo.

Further, when the water heater is not operated during summer or the like, water pressure is no longer applied, but the water drain valve 9 remains closed due to factors such as its own weight.

Next, when the water heater is out of operation in winter and the temperature reaches nearly 0°C, the bimetal 12 flips upward and the valve lever 13
The drain valve 9 is pushed up through the .

However, since the valve seat 8 is now opened, the residual water in the water circuit 1 flows from the water drain passage 7 to the water passage hole 14 of the bimetal 12 and is discharged from the drain port 11 of the case 10.

From the above, the water circuit 1 becomes empty and no freezing occurs.

Furthermore, when water is caused to flow into the water circuit 1 from the water draining state and the water heater is put into operation again, the water pressure pushes down the water drain valve 9 and closes the water drain passage 7.

In addition, FIG. 3 shows another embodiment of the drain passage, and it is functionally similar to the second embodiment.
It is the same as the one shown in the figure.

In this way, the present invention opens the water drain valve by reversing the bimetal that accurately responds to the outside temperature and automatically drains the water from the water circuit, thereby reliably preventing the water from freezing. There is no equipment damage or malfunction.

Moreover, when the water heater is in operation, the water drain valve is closed in any case, and there is no problem with the above-mentioned operation.

Furthermore, since the bimetal is held between the main body of the water draining device and the case having the drain port, the structure is extremely simple and compact.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a water heater showing an embodiment of the present invention, FIG. 2 is a sectional view of a water draining device, and FIG. 3 is a sectional view of a water draining device in another embodiment. 1...Water circuit, 7...Water drain, 9...
...Drain valve, 12...Bimetal.

Claims (1)

[Scope of utility model registration request] A water drain passage connected to the downstream side of the faucet in the water circuit of the water heater;
The drain valve opens and closes the water drain passage and is pushed in the closing direction by the pressure of the water flowing in the water circuit, and the drain valve is installed in a place that is easily affected by the outside temperature and reverses when the ambient temperature is near 0°C. It is made of a bimetal that applies a force in the closing direction to the water drain valve, and the opening force of the water drain valve due to the pressure flowing in the water circuit is set to be larger than the opening force due to bimetal reversal,
A freezing prevention device for a water heater, wherein the bimetal is provided with a water passage hole, and the bimetal is further sandwiched between a water draining device main body and a case having a drain port.