JP3106697B2 - Automatic 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 an automatic hot water supply device used at home and the like for automatically filling a bath.

[0002]

2. Description of the Related Art In recent years, an automatic hot water supply apparatus for automatically filling a bath with hot water has been increasing.

Conventionally, this type of automatic hot water supply apparatus has a configuration as disclosed in Japanese Patent Application Laid-Open No. 63-21439, for example. Hereinafter, the configuration will be described with reference to FIG.

[0004] As shown in the figure, a bath apparatus 7 composed of a return pipe 3 provided with a water pressure detector 4 and a forward pipe 5 provided with a circulation pump 6 is provided in a bathtub 1 by a reheating circulation pipe 2. It is connected. A water heater 11 is connected to the bath device 7 via a drop valve 8, a hopper 9, and a three-way valve 10. The return pipe 3 and the forward pipe 5 are connected by a bypass valve 12 and a bypass pipe 13.

When the bathtub 1 is to be automatically filled with water in the above configuration, the dropping valve 8 is opened, the three-way valve 10 is switched to the forward pipe 5 side, and the circulation pump 6 is operated. As a result, hot water is supplied from the water heater 11 to the bathtub 1 through the additional heating circulation pipe 2. In this hot water supply, when there is no residual water in the bathtub 1, the bypass valve 12 is opened, water is passed from the bypass pipe 13 to the return pipe 3, and the reheating steam circulation pipe 2 between the water pressure detector 4 and the bathtub 1 is opened. Air purging is performed, and then the bypass valve 12 is closed and hot water is supplied to the bathtub 1 from the forward pipe 5 until the water pressure detector 4 detects a predetermined water level in the bathtub 1. The water level in the bathtub 1 can be detected by the water pressure detector 4 without passing air by performing the air purging of the reheating circulation pipe 2 in this manner.

[0006]

In such a conventional automatic hot water supply apparatus, when the water supply pressure is low and the flow rate of the hot water supply is low, and when the reheating circulation pipe 2 is long, the water pressure detector 4 and the bathtub 1 are connected. The inside of the reheating circulation pipe 2 cannot be sufficiently purged with air, and the water pressure detector 4 detects the water pressure, that is, the water level of the bathtub 1 by the pressure propagated in a state where water and air are mixed. In addition, since the detection pressure changes each time the ratio of water to air changes, the water level cannot always be detected under the same conditions, and as a result, the water level in the bathtub at the time of completion of the filling is not accurately obtained. was there.

The present invention solves the above-mentioned problem. Even when the feed water pressure is low and the flow rate of hot water is low, and the recirculation pipe is long, the water level is always detected under the same conditions and the bath water level at the completion of hot water filling is determined. It is an object of the present invention to provide an automatic hot water supply device that can be obtained accurately.

[0008]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides recirculation by a forward pipe and a return pipe connected to a bathtub.
Reheating means forming an annular path and disposed on the return pipe
A water level detector for detecting a bathtub water level by pressure , a two-way valve and a circulating pump, hot water supply means connected to the reheating means via an electromagnetic valve, and control means for performing filling control, and the control means Remains in the bathtub when performing hot water filling operation.
When it is determined that there is no water, the circulation pump is always operated for a predetermined time.
After discharging residual water in the reheating circuit, a two-way valve
The bathtub level with air interposed.
It is configured so that:

[0009]

When the bathtub is automatically filled with water in the above configuration, if there is no remaining water in the bathtub, the circulation pump is operated for a time sufficient to discharge the remaining water in the connection pipe. Hot water is supplied from the hot water supply means to the bathtub through the connection pipe, and the water level detector detects the predetermined water level in the bathtub, closes the solenoid valve and completes pouring, and discharges residual water in the reheating steam circulation pipe to discharge water. The detector detects the water level in the bathtub using only the static pressure of the air alone.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG. In the figure, reference numeral 21 denotes reheating means, which is provided with a return pipe 25 in which a water level detector 22, a two-way valve 23 and a circulation pump 24 are disposed, a reheating burner 26 and a reheating heat exchanger 27. It is formed by a forward pipe 28 connected to the return pipe 25. Reference numeral 29 denotes a hot water supply means, which is a water supply port 31, a hot water supply port 32, a hot water supply burner 33, a hot water supply heat exchanger 34, which branches off from the hot water supply port 32, and which is branched from the hot water supply port 32 through a solenoid valve 35 as a cut-off means. Hopper 36
And a pouring pipe 37 that communicates with the pipe. 38 is a control means which takes in the signal of the water level detector 22 and
The circulation pump 24, the reheating burner 26, the hot water supply burner 33, the solenoid valve 35, and the like are operated. 3
A bathtub 9 is connected to the return pipe 25 and the forward pipe 28 of the reheating unit 21 by two connecting pipes 40a and 40b, respectively. The connection pipes 40a and 40b, the return pipe 25, and the forward pipe 28 form a reheating circulating pipe of the reheating means 21.

In the above construction, when filling the bathtub 39 with no residual water automatically, first, the water level detector 22 detects a pressure sufficiently lower than the pressure at the time of the previous filling and transmits it to the control means 38. . Based on this signal, the control means 38 determines that there is no residual water in the bathtub 39 (determines that there is no residual water even during the first operation), opens the two-way valve 23, and operates the circulation pump 24. At this time, even if the water in the bathtub 39 previously filled with water is drained, the connection pipes 40a and 40b and the return pipe 2
5. Water is left in the forward pipe 28, and if the remaining water is not discharged, a problem occurs in that the water level is detected by the pressure transmitted in a state where water and air are mixed as shown in the conventional example. .

On the other hand, in the present embodiment, the control means 38
When the control means 38 determines that there is no residual water in the bathtub 39, the control means 38 opens the two-way valve 23 and connects the connection pipes 40a, 40b, the return pipe 25,
The circulation pump 24 is operated for a time sufficient to discharge the residual water in the outgoing pipe 28 to the bathtub 39, and the residual water in each pipe is discharged.

When the operation of the circulation pump is completed, the control means 38 stops the circulation pump 24, closes the two-way valve 23, opens the solenoid valve 35, ignites the hot water supply burner 33, and operates the hot water supply means 29. The hot water that enters through the water supply port 31 and is heated by the hot water supply heat exchanger 34 is supplied to the solenoid valve 35 and the hopper 3
6. Hot water is supplied to the bathtub 39 through the pouring pipe 37, the outgoing pipe 28, and the connecting pipe 40b. When the water level detector 22 detects a predetermined water level in the bathtub 39 by the pressure of air, the hot water supply burner 3
3 is stopped, and the solenoid valve 35 is closed to complete the hot water supply operation.

When the temperature of the hot water in the bathtub 39 drops, the reburning burner 26 of the reheating device 21 is ignited, the two-way valve 23 is opened, the circulating pump 24 is operated, and the recirculating pump 24 is operated. The water temperature in the bathtub 39 is raised by heating the water with the reheating heat exchanger 27.

As described above, according to the automatic hot water supply apparatus of the embodiment of the present invention, when there is no remaining water in the bathtub 39, the circulation pump 24 is operated for a time sufficient to discharge the remaining water in the reheating circulation pipe. After the remaining water in the connection pipes 40a and 40b, the return pipe 25, and the outgoing pipe 28 is completely discharged by the circulation pump 24, the two-way valve 23 is closed, and the water level detector 22 detects the water level in the bathtub 39. Can be detected by the static pressure of only air. Thereby, since the water level detection is always performed under the same condition, there is an effect that the bathtub water level at the time of completion of hot water filling can be accurately obtained.

[0016]

As is apparent from the above description of the embodiment, according to the present invention, when there is no residual water in the bathtub, the control means circulates for a sufficient time to discharge the residual water in the reheating circulation pipe. By operating the pump, the supply water pressure is low, the flow rate of the hot water is low, and even when the reheating circulation pipe is long, the residual water in the reheating circulation pipe is discharged, and the water level detector 22 detects the water level in the bathtub. It can be detected by the static pressure of only air. As a result, the water level detection is always performed under the same conditions, so that it is possible to provide an automatic water heater that can accurately obtain the bathtub water level at the completion of filling.

[Brief description of the drawings]

FIG. 1 is a system diagram of an automatic water heater according to one embodiment of the present invention.

FIG. 2 is a system diagram of a conventional automatic water heater.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 21 Reheating means 22 Water level detector 23 Two-way valve 24 Circulation pump 25 Return pipe (Reheating pipe) 28 Outgoing pipe (Reheating circulation pipe) 29 Hot water supply means 35 Solenoid valve 38 Control means 39 Bathtub 40a Connection pipe (Reheating) Circulation pipe) 40b Connection pipe (reheating pipe)

Continuation of the front page (56) References JP-A-2-306054 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F24H 1/00 606

Claims (1)

(57) [Claims] (1) recirculation by a forward pipe and a return pipe connected to a bathtub;
Reheating means forming an annular path and disposed on the return pipe
A water level detector for detecting a bathtub water level by pressure , a two-way valve and a circulation pump, a hot water supply means connected to the reheating means via an electromagnetic valve, and a control means for performing filling control, the control means Remains in the bathtub when performing hot water filling operation.
When it is determined that there is no water, the circulation pump is always operated for a predetermined time.
After discharging residual water in the reheating circuit, a two-way valve
The bathtub level with air interposed.
Automatic hot water supply apparatus to so that.