JPH0594649U - Electric water heater - Google Patents

Abstract

(57) [Summary] [Purpose] Before starting hot water for a day or when hot water is not used for a long time, replace old water with new water and heat it to supply good quality hot water. [Structure] A second drainage pipe connected to a tank is provided with an electromagnetically operated second on-off valve 8b, which outputs a drainage signal at a set time before the heating start time of one day to output the second on-off valve 8b. Open and drain the water in the tank. In addition, the water flow sensor 22 detects that the water supply to the tank has stopped, and the counter 20 measures the time during which the water supply stop state continues, and when the water supply stop continuation time exceeds the set time, the drain signal Is output to open the second opening / closing valve 8b, and the water in the tank is discharged.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an electric water heater.

[0002]

[Prior Art]

 As a result of the trend toward shorter working hours in recent years, the actual operating hours of electric water heaters installed in office buildings, etc. have been significantly reduced due to the introduction of a two-day work week and the introduction of large consecutive holidays.

Therefore, the operation time of the electric water heater is controlled by a weekly timer or the like to avoid wasteful heating, or to prevent the hot water supply temperature from becoming too high by setting the hot water supply temperature to a desired temperature. Improvements have been made such that heating is only performed when water is replenished using sensors such as makeup water or operating conditions are saved by controlling hot water supply conditions.

[0004]

[Problems to be solved by the device]

 However, in the above-mentioned electric water heater, for example, hot water boiled at a high temperature of 95 ° C does not use for a long time such as on holidays, at night, or even when chlorine for sterilization flies away. In this case, the hot water was left to cool and then germinated, so that the water with deteriorated quality had to be heated again before the holidays and used for hot water supply.

The present invention has been made in view of the above circumstances, and the electric water heater according to the first aspect of the present invention replaces old water with fresh water before starting hot water supply for one day. The purpose of the electric water heater of the present invention is to replace old water with new water when it is not used for a long time. The purpose is to replace the water with water and heat it so that high-quality hot water can be supplied.

[0006]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the electric water heater of the invention according to claim 1 is provided with an electromagnetically operated on-off valve in the drain pipe connected to the tank, and the set time is longer than the heating start time of one day. It is equipped with a drainage control means that outputs a drainage signal to open the on-off valve and drains the water in the tank.

In order to achieve the above-mentioned object, the electric water heater according to the second aspect of the invention has a water supply stop determination means for detecting that the water supply to the tank has stopped, and the water supply stop determination. After the start of the water supply stop by the means, when the water supply stop duration measuring means for measuring the duration of the water supply stop state and the water supply stop duration measured by the water supply stop duration measuring means exceeds the set time A safety drain control means for outputting a drain signal to open the on-off valve and discharging the water in the tank.

[0008]

[Action]

 According to the configuration of the electric water heater of the invention according to claim 1, for example, in the case where heating is started from 8:20 in order to use hot water from 8:30 in the morning, 5 minutes after that, etc. When the time before the set time of is reached, the water accumulated in the tank can be automatically discharged and replaced with new water, and the new water can be heated to supply hot water.

Further, according to the configuration of the electric water heater of the invention according to claim 2, when the state where the hot water is not used for a set time continues, the water accumulated in the tank is automatically discharged. It can be replaced with fresh water and the new water can be heated to supply hot water.

[0010]

【Example】

 Next, an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a partially cutaway side view of an electric water heater according to the present invention, in which a heater 2 is provided in a tank 1 and water is supplied when the amount of water in the tank 1 falls below a set amount. On the other hand, a water supply pipe 4 is connected through a water supply valve mechanism (ball tap) 3 that stops the water supply when the amount of water exceeds a set amount.

Further, in the tank 1, a hot water supply pipe 5 and a first drain pipe 6 for discharging water when the amount of water exceeds a set amount when the water supply valve mechanism 3 fails are connected, and further, A second drain pipe 7 is connected to the bottom of the tank 1, an electromagnetically operated first opening / closing valve 8a is provided in the water supply pipe 4, and an electromagnetically operated second opening / closing valve is provided in the second drain pipe 7. A valve 8b is provided.

A hot water thermometer 9 for measuring the hot water temperature is provided above the inside of the tank 1, and the hot water thermometer 9, the heater 2, and a hot water temperature setting device 10 for setting the hot water temperature are micro. It is connected to the computer 11. As shown in the block diagram of FIG. 2, the microcomputer 11 is provided with a first comparing means 12, a second comparing means 13, a heater stopping means 14, and a heater starting means 15.

In the first comparison means 12, the hot water temperature measured by the hot water thermometer 9 and the hot water temperature set by the hot water temperature setting device 10 are compared, and the hot water temperature is set to a set temperature (for example, 90 ° C.). When it exceeds, the heater stop means 14 outputs a comparison output, and in response to the comparison output, the heater stop means 14 cuts off the power supply to the heater 2 to stop the heating.

In the second comparison means 13, the water temperature measured by the water temperature gauge 9 and the lower limit temperature set lower than the water temperature set by the water temperature setting device 10 by a predetermined temperature (for example, 5 ° C.). When the temperature becomes lower than the lower limit set temperature (for example, 85 ° C.), a comparison output is output to the heater starting means 15, and the heater starting means 15 energizes the heater 2 in response to the comparison output. To start heating.

Further, the microcomputer 11 is provided with a drainage control means 18 including a drainage timing determination means 16 and a valve driving means 17, and a weekly timer 19 is connected to the drainage timing determination means 16 and a weekly timer 19 is used. Based on the measured time, it is judged whether it is a set time (for example, 5 minutes) before the heating start time of the day, that is, whether it is the drainage time, and when the drainage time comes A command signal is output to the drive means 17, and in response to the command signal, the valve drive means 17 outputs a drainage signal to the first and second opening / closing valves 8a and 8b for a set time, and the first opening / closing operation is performed. The valve 8a is closed to stop the water supply, and the second opening / closing valve 8b is opened to discharge the entire amount of water in the tank 1.

Further, the microcomputer 11 is provided with a counter 20 as a water supply stop duration measuring means for measuring the duration of the water supply stop state and a third comparing means 21, while the water supply pipe 4 is provided. A water flow sensor 22 as a water supply stop determination means for determining whether or not the water supply is stopped due to the water flow is attached to the water flow sensor 22. The water flow sensor 22 is connected to the counter 20, and the counter 20 is activated when the water supply stop is started. On the other hand, the counter 20 is reset with the start of water supply. As the water supply stop determination means, for example, a ball tap actuation switch that detects that the water supply valve mechanism 3 has actuated is attached, and the water supply stop state is determined by the fact that the ball tap operation switch does not operate. Alternatively, paying attention to the fact that the amount of hot water accumulated in the tank 1 is constant and using a level meter that detects that a certain amount of hot water is accumulated Various configurations such as a configuration for determining the stopped state can be adopted.

The time set by the time setter 23 (for example, 6 hours) and the water supply stop duration measured by the counter 20 are input to the third comparison means 21, and the water supply stop duration is input. When the set time is exceeded, a command signal is output to the heater 2 and the valve driving means 17, and in response to the command signal, the heater 2 is de-energized to stop heating, and the valve driving means 17 The drainage signal is output to the first and second on-off valves 8a and 8b for a set time, the first on-off valve 8a is closed to stop the water supply, and the second on-off valve 8b is opened to store the total amount in the tank 1. It is designed to drain water. The signal from the weekly timer 19 is input to the counter 20, and the counter 20 is reset when the hot water is supplied from the time when hot water is supplied, and the time is measured by the counter 20 when the hot water is not supplied. It is supposed to stop.

The counter 20, the third comparing means 21, the water flow sensor 22, the time setting device 23, and the valve driving means 17 are referred to as safe drainage control means.

The control operation by the microcomputer 11 will be described with reference to the flowchart of FIG.

First, the time by the weekly timer 19 is input to the drainage timing determination means 16 (S1), and it is determined based on the time whether or not the preset heating start time comes before the set time (step S1). S2).

When it is before the set time, the drainage timing determination means 16 outputs an instruction signal to the valve driving means 17, and the process proceeds to step S3, where the valve driving means 17 causes the first and second on-off valves 8a, The drainage signal is output to 8b, the first on-off valve 8a is closed, the second on-off valve 8b is opened (S4), and that state is maintained for a set time (S5), and the total amount of water in the tank Is discharged.

After the discharge is completed, the first opening / closing valve 8a is opened, the second opening / closing valve 8b is closed (S6), and new water is supplied into the tank 1. When a predetermined amount of water is supplied, the water supply valve mechanism 3 is activated to naturally stop the water supply, and water exceeding the set amount is discharged from the first drain pipe 6.

Next, when the weekly timer 19 is turned on (S7), the heater 2 is energized (ON) to start heating (S8), and heating is started. Judge whether the water supply stop duration exceeds the set time. At the initial stage, the set time is not exceeded, so the routine proceeds to step S10, where it is determined whether the hot water temperature is equal to or higher than the set temperature.

In step S10, if the hot water temperature is equal to or higher than the set temperature, the power supply to the heater 2 is cut off and the heating is stopped (S11). Then, once the heating is stopped and the temperature is lowered, the process proceeds from step S10 to step S12, and it is determined whether the hot water temperature is equal to or lower than the lower limit side set temperature which is a predetermined temperature lower than the set temperature, and the lower limit side set temperature is set. If the temperature becomes equal to or less than that, heating is restarted by returning to step S8. On the other hand, if the temperature is not lower than the lower limit set temperature, it is determined that the hot water temperature is appropriate and the process proceeds to step S11.

If the hot water is not supplied for a long time such as 6 hours from the morning, it is determined in step S9, the process proceeds to step S13, the power supply to the heater 2 is cut off to stop the heating, and then step S3. And drain the water in tank 1 and replace it with new water.

When it is determined that the weekly timer 19 is turned off in step S14, the process proceeds to step S15, the counter 15 is reset, and then the process returns to step S1.

As described above, before starting heating such as in the morning or when not used for a long time, all the water that had been in the tank 1 until then is replaced with new water, and various bacteria propagate. It is possible to avoid hot water supply due to water with poor quality.

The present invention can be applied to both a wall-mounted electric water heater and a stationary electric water heater that is stored under a sink.

[0030]

[Effect of the device]

 As explained above, according to the electric water heater of the invention according to claim 1, it is possible to avoid using the water whose water quality is deteriorated due to the propagation of various bacteria as it is for hot water supply after holidays and nights. It is possible to supply high-quality hot water obtained by heating water.

Further, according to the electric water heater of the invention according to claim 2, if the state where hot water is not used for a set time or more continues due to holidays, nighttime, or absence, the quality of the water is deteriorated. Since it is replaced with fresh water, it is possible to constantly supply high-quality hot water obtained by heating fresh water.

[Brief description of drawings]

FIG. 1 is a partially cutaway side view showing an electric water heater according to the present invention.

FIG. 2 is a block diagram.

FIG. 3 is a flowchart illustrating a control operation by a microcomputer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Tank 7 ... 2nd drainage pipe 8a ... 1st opening / closing valve 8b ... 2nd opening / closing valve 18 ... Drainage control means 20 ... Counter as water supply stop duration measuring means 22 ... Water flow sensor as water supply stop determination means

Claims (2)

[Scope of utility model registration request] 1. A drainage pipe connected to a tank is provided with an electromagnetically operated on-off valve, which outputs a drainage signal to open the on-off valve before a set time before the heating start time of one day to open the water in the tank. An electric water heater comprising drainage control means for discharging the water. 2. A water supply stop determination means for detecting that the water supply to the tank has stopped, and a water supply stop duration time for measuring a time during which the water supply stop state continues after the water supply stop determination means starts the water supply stop. Safety drainage control that outputs a drainage signal and opens the on-off valve to discharge the water in the tank when the water supply stop duration measured by the water supply stop duration measuring means exceeds a set time. The electric water heater according to claim 1, further comprising: