JP3074962B2 - Water heater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot water heater mainly used for homes, using oil or gas as a heat source.

[0002]

2. Description of the Related Art In general, in a pre-stop type or main stop type instantaneous water heater, as shown in FIG. The hot water remaining in the heat exchanger 1 becomes hot and is discharged from the hot water path 10 when the hot water is shortly used after the stoppage of use, and is inconvenient for use. In order to reduce boiling, a bypass solenoid valve 7 is provided in the bypass water supply passage 8. At the time of tapping, the bypass feedwater is mixed with the high-temperature water in the tapping water passage 10 by opening and closing the bypass solenoid valve 7. Hot water was decreasing.

[0003]

In such a conventional opening and closing of the bypass solenoid valve 7 of the bypass water supply passage 8, after passing water,
When the bypass solenoid valve 7 is closed, a water hammer is generated when the bypass water supply passage 8 is suddenly closed, so that vibration and noise are increased. Further, pressure stress applied to the pipe and the heat exchanger 1 increases, and durability decreases.

[0004] Therefore, an object of the present invention is to provide a water heater that reduces hot water tapping at the start of tapping due to boiling and reduces vibration and noise.

[0005]

In order to solve the above-mentioned problems, a water heater according to the present invention is provided with a leak passage such as a leak slit or a small hole in a bypass water supply passage connecting an inlet side and an outlet side of a heat exchanger. Provided with a bypass solenoid valve.

[0006]

According to the present invention, when the bypass solenoid valve of the bypass water supply passage is opened and closed, a small amount of water continues to flow from the leak passage even when the bypass solenoid valve is closed after water is supplied. It does not become in the state of sudden closing, and the occurrence of water hammer can be reduced.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings of a water heater of a pre-stop type. In FIG. 1, a heat exchanger 1 is provided above a combustion burner 2, and the heat exchanger 1 is configured such that feed water is heated by combustion heat of the combustion burner 2.
A flow rate sensor 3 for detecting a flow rate of water supply is provided in a water supply path 6 on the inlet side of the heat exchanger 1, and a hot water supply detector 5 for detecting a temperature of hot water is provided in a hot water supply path 6 on the outlet side.

A bypass water supply passage 8 connected between the inlet side and the outlet side of the heat exchanger 1 via a bypass solenoid valve 7 is
A part of the feed water is mixed with the hot water heated by the heat exchanger 1 at the outlet side of the heat exchanger 1 without being heated by the heat exchanger 1. The controller 9 controls the combustion amount of the combustion burner 2 and the bypass solenoid valve 7 based on signals from the flow rate sensor 3 and the hot water supply temperature detector 5.

As shown in FIG. 2, the bypass solenoid valve 7 has a valve seat 13 provided with a leak slit 14 as a leak passage between an inlet and an outlet of a body 11, and a valve 12 having a plunger 15 and a spring. 17, it is normally pressed, and the space between the inlet and the outlet of the bypass solenoid valve 7 is closed. If the electromagnetic coil 16 is energized, the plunger 15
Is sucked and the valve 12 is opened.

The operation of the above configuration will be described. When the tapping is started, the flow rate sensor 3 detects the flow rate and controls the control unit 9 to open the bypass solenoid valve 7 for a preset time, and closes after the set time. That is, the electromagnetic coil 16 of the bypass solenoid valve 17 is energized simultaneously with the start of hot water supply, the plunger 15 is sucked against the spring 17, the valve 12 opens, water flows through the bypass water supply passage 8, and is heated by the heat exchanger 1. The mixed water is mixed with the hot water. After a set time, the electromagnetic coil 16 of the bypass solenoid valve 17
Is stopped, the plunger 15 is set in the spring 17.
The valve 12 is pressed against the valve seat 13 as shown in FIG. 2 and most of the water flowing through the bypass water supply passage 8 is stopped. (3% of the total flow rate when the bypass water supply channel 8 is fully opened)
Water continues to flow. Therefore, the water in the bypass water supply channel 8 does not suddenly stop completely, so that the water hammer is reduced.

The shape of the leak slit 14 is as follows.
As shown in FIG. 3, the trapezoidal shape was good in the experiment.

As shown in FIG. 4, even if a small hole 18 for leakage is provided in the valve seat 13,
In addition, even if the leak slit 17 is provided, it has the same function as described above, and the water hammer can be reduced.

[0013]

As described above, according to the water heater of the present invention, the following effects can be obtained. In other words, even when the bypass solenoid valve of the bypass water supply passage is closed, a very small amount of water continues to flow from the leak passage, so that the bypass water supply does not suddenly close, reducing the occurrence of water hammer, reducing vibration and noise. Can be reduced.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a water heater in one embodiment of the present invention.

FIG. 2 is a sectional view of a bypass solenoid valve of the water heater.

FIG. 3A is a plan view of a valve seat portion of a bypass solenoid valve of the water heater. FIG. 3B is a cross-sectional view of the valve seat portion.

FIG. 4 is a sectional view of another embodiment of the bypass solenoid valve of the water heater.

FIG. 5 is a sectional view of another embodiment of the bypass solenoid valve of the water heater.

FIG. 6 is a configuration diagram of a conventional water heater.

[Explanation of symbols]

 Reference Signs List 1 heat exchanger 7 bypass solenoid valve 8 bypass water supply passage 14 leak slit (leak passage)

Continuation of the front page (56) References JP-A-3-230053 (JP, A) JP-A-62-119357 (JP, A) JP-A-61-55646 (JP, U) JP-A-60-4841 (JP, A) , U) Actually open 1979-52062 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F24H 1/10 302 F24H 1/10 303 F24H 9/00

Claims (1)

(57) [Claims] 1. A heat exchanger, a heating source for heating water supplied to the heat exchanger, a bypass water supply path connecting an inlet side and an outlet side of the heat exchanger, and a hot water supply provided in the bypass water supply path. A water heater that opens and closes in response to a stop of hot water supply and includes a bypass solenoid valve having a leak passage.