JPH0620425B2 - Waterway backflow prevention device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a backflow prevention device for a water channel used for connecting a tap water and a water circuit.

(Prior Art and Problems) As a conventional device of this type, as shown in FIG. 4, a water heater (not shown) which is a bath (A) which is a water circuit and a water circuit (C) which is a water circuit. In the case of connecting the and, the vacuum breaker (B) should be placed at a position 30 cm or more from the overflow edge of the bathtub (A).
Was installed to prevent backflow of miscellaneous water into the clean water circuit (C).
However, this has restrictions on the piping of the water supply circuit (C), and when attempting to build the vacuum breaker (B) into the water heater, there were problems such as restrictions on the mounting position and complication of the internal structure of the equipment.

In addition, as a means to solve these problems, the actual development of Sho 61-1
There is one disclosed in Japanese Patent No. 19063, but this has a complicated structure of the backflow prevention device, and when the miscellaneous water circuit becomes negative pressure for some reason, the drain passage remains blocked from the water passage. It was not perfect in terms of performance.

The present invention solves the above problems, and aims to provide a waterway backflow preventive device that does not have restrictions on the mounting position of appliances and complicates the internal structure of appliances, and is compact and inexpensive and has satisfactory performance. is there.

(Means for Solving Problems) In order to achieve the above object, the present invention provides a check valve in a water channel (C).
(E) (F) is arranged in series and closes when water pressure is applied between the check valves (E) and (F), and opens when water pressure disappears to open the waterway to the atmosphere (G) It is characterized by having arranged.

(Function) Since the atmosphere release valve (G) is closed when water is flowing through the water channel (C), water flows in the water channel (C) in the forward direction. When water flow stops, the check valves (E) and (F) close and the atmosphere release valve (G) opens.
A part of the waterway (C) is opened to the atmosphere and cut off.
Also, if water flows back while the check valves (E) and (F) are out of order, the backflow water will not be discharged to the outside of the water channel (C) from the atmosphere release valve (G) and will not flow upstream.

(Example) An example of the present invention will be described with reference to the drawings. (A) is a bathtub that is a part of the miscellaneous water circuit, and (C) is a clean water circuit connected to a water heater or a water source (not shown), and both circuits are directly connected. (D) is a backflow preventive device, in which the first check valve (E) and the second check valve (F) are arranged in series, and the atmosphere release valve (G) is arranged between them.

(1) is a valve body of the first non-stop water (E), which is biased in the reverse water flow direction by a spring (4). (2) is the second check valve (F)
The valve body is urged in the reverse water flow direction by the spring (6). (3) is the valve body of the atmosphere release valve (G), which is a double check valve (E)
It is arranged in the air chamber (8) formed between (F) and opens and closes the air port (7) formed in the water channel wall (9). The atmosphere release valve body (3) is opened when the first check valve body (1) is closed. The valve rod (11) is engaged with the valve shaft (10) and the valve body (3) is opened when the valve body (1) is opened. ), A spring (5) for urging both valve bodies in the separating direction is provided.

The atmosphere release valve (G) may be independent of the check valve (E) or (F). Further, the first check valve (E) and the second check valve (F) may have a check function and may be configured by electromagnetic valves that open and close by electromagnetic force.

Next, the operation of the above configuration will be described. Normal time,
When supplying hot water to the bathtub (A), the valve body (1) of the first check valve (E) is pushed open by the water flow pressure, and the second check valve (F) is also opened, so that water flows. At this time, the atmosphere opening valve body (3) closes the air port (7) by the water flowing in the air chamber (8), so that the water does not flow out of the water channel. When the water flow is stopped, the two check valve bodies (1) and (2) close the water channels by the springs (4) and (6). At this time, the valve rod (11) is hooked on the valve shaft (10) to open the valve body (3). Therefore, the air entered from the air port (7) is replaced with water and the air chamber (8) is filled.

When the sewage circuit has a positive pressure, such as when the bathtub (A) is on the second floor, the sewage is discharged from the air channel (7) to the outside of the waterway even if the check valve (F) is defective. Does not flow to the water side.

Also, if the water supply circuit (C) becomes negative due to the water supply being cut off, even if the check valve (E) is out of order, only the air will be sucked in and the miscellaneous water will not flow back.

When the miscellaneous water circuit becomes strongly negative, the check valve body (2) is opened and a force in the opening direction is also applied to the atmosphere release valve body (3), so that air is sucked in from the air port (7), Separated from clean water.

(Effects of the Invention) As described above, according to the present invention, the check valves are arranged in series in the water passage and the atmosphere opening valve is provided between the check valves. Next to it, the waterway can be completely cut off. Moreover, the structure of the device itself is simple,
There is no restriction on the mounting position, and the structure inside the device is simplified.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of the present invention, FIGS. 2 and 3 are one embodiment of the present invention, FIG. 2 is a sectional view when water is stopped, and FIG. 3 is a sectional view when water is passed. is there. FIG. 4 is a conceptual diagram of a conventional example. (A) …… Bathtub (poor water circuit) (C) …… Water supply circuit (E) (F) …… Check valve (G) …… Air release valve

Claims (1)

[Claims] Claims: 1. A check valve is arranged in series in a water channel, and an atmosphere release valve is provided which closes when water pressure is applied between the check valves and opens when water pressure disappears to open the water channel to the atmosphere. A waterway backflow prevention device.