JPS6115478Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an instantaneous water heater and aims to prevent the water heater from freezing.

Various methods have been proposed to prevent instantaneous water heaters from freezing, and one method is to constantly allow a small amount of water to flow through the water heater. According to experiments, freezing can be prevented by running water at a rate of about 200 c.c./min at -10°C. Therefore, low-temperature operating valves are now in practical use that automatically open when the outside air temperature or water temperature approaches freezing temperatures, allowing water to flow at a rate of about 200 c.c./min.
However, when using this low-temperature operating valve to prevent freezing, if a bypass path is provided in the flow path of the instantaneous water heater in parallel with the heat exchanger, the flow will flow in parallel to the heat exchanger and the bypass path, so 200 c.c. When water flows at a rate of about ./min, the amount of water flowing through the heat exchanger side is about half, 100%.
cc/min, and at temperatures as low as -10°C, the heat exchanger will freeze. Therefore, in order to solve this problem, the flow rate of the low-temperature operating valve must be doubled to about 400 c.c./min, which results in wasted water. Also, between the bypass path and the heat exchanger, the bypass path has less water flow resistance,
It is not possible to always ensure a sufficient amount of water flowing to the heat exchanger side. FIG. 1 shows an instantaneous water heater having a bypass passage, where 1 is a flow channel, and the middle portion of this flow channel 1 passes through a heat exchanger 2. Reference numeral 3 denotes a bypass passage that communicates between the flow passages 1 and 1 on both sides of the heat exchanger 2, and a hydraulic response valve 4 is provided in the communication portion between the flow passage 1 and the bypass passage 3 on the water supply side. This water pressure responsive valve 4 detects the flow of water in the flow channel 1 and opens the gas valve 5 to supply gas to the main burner 6. The gas supplied to the main burner 6 is passed through the pilot burner 7. It is ignited and heats the heat exchanger 2. Further, the hydraulic response valve 4 has an on-off valve for the bypass path 3. A low-temperature operating valve 8 is installed in the water supply channel 1. At low temperatures, this low-temperature operating valve 8 allows approximately 200 c.c./min of water to flow into the channel 1 and into the bypass. This prevents freezing in Road 3. Reference numeral 9 denotes a gas main valve provided on the upper side of the gas valve 5.

FIG. 2 shows details of a conventional example of the hydraulically responsive valve 4, with reference numerals 11 and 12 representing an inlet and an outlet connected to the flow channel 1. Water flows into the water pressure responsive valve 4 from the inlet portion 11, is reduced to a predetermined pressure by the governor 13, and is then transferred to the high pressure portion 14 and the ventilator 15.
It flows out from the outlet part 12 to the heat exchanger 2 side through the low pressure part 16 created by the heat exchanger. The pressure in the low pressure section 16 is led to the low pressure chamber 18 through the passage 17, and therefore, when water is flowing, the load on the diaphragm 19 overcomes the load on the spring 20 due to the differential pressure, pushing up the rod 10 and opening the gas valve 5. be able to. On the other hand, the water in the high pressure section 14 is connected to the connection section 2 with the bypass path 3.
1 side through the bypass valve 22.
Bypass valve 22 is interlocked with diaphragm 23 .
The pressure in the low pressure section 16 is guided to the low pressure chamber 25 via the passage 24, but since the pressure of the water flowing from the high pressure section 14 to the bypass valve 22 side is higher, the bypass valve 22 is guided to the low pressure chamber 25 pressure. It overcomes this and descends, closing the bypass road 3. However, the passage 24 has a ball 26 and a bypass passage 27, and instead of closing the bypass passage 3 instantaneously when water flows, the main passage 28 of the passage 24 is closed by the ball 26, and only the bypass passage 27 is filled with water. As the water flows, the water in the low pressure chamber 25 passes through the bypass passage 27 and is discharged, so that the water in the low pressure chamber 25 passes through the bypass passage 27 and is discharged until the bypass valve 22 closes.
It takes about seconds, and water flows into the bypass path 3 only during that time. In other words, water is allowed to flow through the bypass path 3 for only about 2 to 3 seconds when the main burner 6 is ignited, and the water is mixed with the high temperature hot water stored in the heat exchanger 2 to alleviate after-boiling.

200 when the low temperature operation valve 8 opens near the freezing temperature.
Water flows at a rate of about cc/min, but the gas valve 5 does not open with this amount of water. According to the water pressure responsive valve 4 shown in FIG. 2, the bypass valve 22 is always open, that is, when the water heater is not in use. 3 flows in parallel, therefore, the heat exchanger 2 cannot secure a sufficient amount of water necessary for freezing prevention, and there is a risk of freezing.

The present invention has been devised to deal with such problems, and will be explained below based on drawings showing embodiments. That is, the present invention provides an instantaneous water heater as shown in FIGS. 1 and 2, in which the relationship between the bypass passage of the water pressure responsive valve and the bypass valve is as shown in FIG. 3 instead of that shown in FIG. 2. It was made into
Since the other configurations are the same as those in FIGS. 1 and 2, only the improved portions will be described. In the present invention, as shown in FIG. 3, a communication port 30 communicating with the connecting portion 21 is formed at the upper end of the valve chamber 29 that accommodates the valve body 22a of the bypass valve 22, and a communication port 30 communicating with the connecting portion 21 is formed at the lower end of the valve chamber 29.
A communication port 31 communicating with the valve element 22a is formed, and both communication ports 30 and 31 can be closed by the upper and lower surfaces of the valve body 22a. The communication port 30, that is, the bypass path 3 is connected to the valve body 22a.
It is normally closed by the top surface of. Therefore, when the water heater is not in use and when water is flowing when the water heater is in use, the bypass valve 22 closes the bypass passage 3.
is closed and the bypass line 3 is closed only for 2 to 3 seconds after the water is flushed.
opens, water flows to the hot water supply side, and prevents overheating. Also, normally the valve body 22a of the bypass valve 22
Since the communication port 30 is closed by the upper surface of the heat exchanger 2, all the water flowing from the low temperature operation valve 8 flows to the heat exchanger 2 side, so that freezing is reliably prevented.

By the way, in the present invention, if a gasket 32 is attached to the upper surface of the valve body 22a of the bypass valve 22, the sealing performance with the communication port 30 can be improved.

The instantaneous water heater of the present invention can be implemented as described above, and has a simple configuration that not only prevents after-boiling but also reliably prevents freezing using as little water as 200c.c./min. It is something.

[Brief explanation of the drawing]

Figure 1 is a schematic configuration diagram of an instantaneous water heater, Figure 2 is a vertical cross-sectional view of a conventional water pressure responsive valve used in an instantaneous water heater,
FIG. 3 is a sectional view of a main part of a water pressure responsive valve used in an instantaneous water heater in an embodiment of the present invention, and FIG. 4 is an explanatory diagram of a bypass valve in an applied example of the present invention. 1...Flow channel, 2...Heat exchanger, 3...Bypass path, 4...Hydraulic pressure responsive valve, 8...Low temperature operation valve, 2
1...Connection part, 22...Bypass valve, 22a...
Valve body, 23...Diaphragm, 29...Valve chamber, 3
0,31...Communication port, 32...Patsukin.

Claims (1)

[Claims for Utility Model Registration] 1. A bypass path is provided that bypasses the water supply side flow path and the hot water supply side flow path without going through a heat exchanger, and a hydraulic responsive diaphragm is provided in the communication portion between the water supply side flow path and the bypass path. A bypass valve is provided that opens and closes the bypass passage in conjunction with the water heater, and when the water heater is not in use, the bypass passage is closed on one side of the bypass valve, and when water is flowing, the bypass passage is closed on the other side of the bypass valve. An instantaneous water heater characterized in that the bypass passage is configured such that the bypass passage opens only at the moment when the bypass valve moves immediately after the water flows. 2 Claim No. 1 for utility model registration, which is characterized in that a gasket is attached to one side of the bypass valve.
Instantaneous water heater as described in section.