JPH0578737B2 - - Google Patents

Description

[Detailed description of the invention] Industrial applications The present invention relates to a water heater.

Conventional technology As shown in Fig. 4, a conventional water heater has an air vent valve provided at the upper hot water supply port of the water heater, a water supply motorized valve 61 provided at the water supply port, and a drain motorized valve 6 provided at the drain port.
2 and a control device that controls the electric valve, and when water is supplied, the water supply electric valve 61 starts to open and the drain electric valve 62 starts to close at the same time, and a preset timer is set until the water heater tank becomes full. energization of the heating devices 66 and 67 starts after a delay. Next, when draining water, after stopping the power supply to the heating device, the water supply motorized valve 6 starts opening at the same time as the water drain motorized valve 62 starts to open.
1 begins to close, and the water heater tank is controlled to discharge hot water. However, according to this configuration, if the drain motorized valve 62 closes completely during water supply, or the water supply motorized valve 61 closes incompletely during draining, or if a power outage occurs during water supply or drainage, the water supply motorized valve 61 closes completely.
1 and the drain electric valve 62 are stopped midway, and water supply and drainage are not performed reliably, resulting in a large loss of tap water and heating power, and at the same time, water remains in the tank even when not in use, shortening the tank life. There is a problem with being short. Also, when water is supplied, even if the relay 57 closes after the set time of the timer
If the circuit breaker 3 is open or the thermostat 65 is open, the heating devices 66 and 67 will not be energized and the water in the water heater will not boil, so this type of water heater takes a long time to boil. This is a serious drawback. In addition, the temperature of the water in the tank was as high as 85°C immediately after use, and there was a problem in that if it was drained as is, it would damage the drainage equipment.

Problems to be Solved by the Invention In such conventional water heaters, the water supply operation, which is performed with the expectation of a series of operations up to the operation of the water heater, may cause failures in closing the electric supply/drainage valves or failures in power supply to the heating device. It is not possible to notify that hot water cannot be supplied due to such reasons. Further, it is impossible to detect a closing failure of the electric water supply valve when a water drain operation is performed for the purpose of draining water inside the tank. Additionally, the above-mentioned system has three problems in that tap water is left flowing in the event of a power outage during supply/drainage.

The present invention has been made in view of these points, and is intended to solve the above problems with a simple configuration.

Means for Solving the Problems In order to solve the above problems, the present invention provides means for detecting the current flowing to the heating device and means for detecting that the electric water supply valve and the electric discharge valve have moved to the closed position. , water supply, and drainage electric valves are configured to operate at staggered times.

Effects The present invention has the above-described configuration, and prevents the inability to supply hot water due to a failure in closing the electric drain valve or a failure in the power supply to the heating device, etc., during water supply operation.
In addition, during drainage operations, it prevents deterioration of tank life due to accumulated water in the tank due to failure of closing the electric water supply valve or failure of opening the electric discharge valve, and also prevents the operation of the electric supply and drainage valves from occurring for a certain amount of time. By staggering the operation, water is prevented from flowing due to a power outage during water supply and drainage.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of a water supply/drainage system for a water heater according to the present invention. In Figure 1, 1 is a tank;
A water heater consisting of a dry boiling prevention device, a heating device, etc., 2 a hot water inlet disposed at the top of the water heater 1, 3
4 is a water inlet located at the bottom of the water heater 1, 4 is a drain port similarly located, and 5 is a drain port that releases air discharged from the hot water inlet 2 into the atmosphere. An air vent valve provided to suck in air,
6 and 7 are also safety valves, 8 is an electric water supply valve arranged to open and close the water flowing into the water supply port, 9 is a pressure reducing check valve, 10 is a stop valve, and 11 is a valve that opens and closes the hot water flowing out from the drain port. 12 is a stop valve, and 13 is a control device. In the following description, stop valves 10 and 12
is open, and the pressure reducing check valve 9 is regulated to a predetermined pressure.

FIG. 2 shows a circuit in one embodiment of the control device 13 of FIG. In FIG. 2, the reversing relay circuit 19 performs a reversing operation each time the operation switch 18 is operated, and the contact 19-1 is repeatedly reversed from (a) to (b) to (a). If you operate the operation switch 18 now, the contact 19-
1 falls to (b), and the relay 20 is energized, so that the contact 20-1 connected to the closing terminal (c) of the electric drain valve 38 closes, thereby closing the electric drain valve 38. When the electric drain valve 38 closes, the contact 38-1 built into the electric drain valve 38 closes, and the relay 22 is energized, thereby opening the contact 22-1 connected to the opening terminal (o) of the electric water supply valve 37. 1 is closed, the electric water supply valve 37 is opened, and water supply to the water heater 1 is started. At this time, the air in the tank of the water heater 1 is discharged by the air vent valve 5, and water is supplied smoothly.

Note that the contact 38-1 incorporated in the electric valve 38
is connected in parallel with the relay 20, and has the same effect even if it is replaced by a time contact of a timer that is preset for a necessary and sufficient time until the electric valve 38 starts energizing and closes.

At the same time as the relay 22 is energized, the timer A24 starts. The timer A24 is a timer that is set for a necessary and sufficient time after starting water supply to the tank of the water heater 1 until it becomes full, and when the time contact 24-1 closes, the relay 25 is energized. .

The timer A24 is a timer for waiting until the tank is filled with water, and is a means for detecting the fullness of the tank of the water heater 1, such as a water level detection device near the upper hot water supply port 2 of the water heater 1. It is also possible to provide an output contact and replace the time contact 24-1, or a contact for setting by a flow rate counter. Contact 25-1 is closed by excitation of relay 25, and if power is supplied from AC power source 40 at this time and the operation of the dry detection device provided in hot water heater 1 is canceled, heater 4, which is a heating device, is closed.
3 and 44 starts to heat the water in the tank, a predetermined heater current flows, and an induced voltage is generated in the sensor coil 26 of the current detection circuit 26 disposed in the energized path. Detection circuit 26
Normally closed contact 26-1 opens and timer D27 does not start. If the predetermined heater current does not flow due to a power outage in the AC power supply 40, an activation of the dry heating prevention device 41, an activation of the safety device 42, or a disconnection of the heater 43 or 44, the current detection circuit When the normally closed contact 26-1 of the keep relay 16 does not open and the time contact 24-1 of the timer A24 closes, the timer D27 starts at the same time, and after a predetermined period of time, the time contact 27-1 closes and the set coil (S) of the keep relay 16 is energized, contact 16-
1 closes and lights up the alarm lamp 17.

Note that the alarm lamp 17 may be a sound alarm means such as a buzzer.

This alarm lamp 17 is activated by removing the reason why the predetermined heater current does not flow, and then pressing the reset switch 15 to excite the reset coil (R) of the keep relay 16 and open the contact 16-1. The lights go out.

Next, when the operation switch 18 is operated again, the contact 19-1 falls to the a side due to the action of the reversing relay circuit 19, the excitation of the relay 25 is released, and the contact 25-1
is opened to stop energizing the heaters 43 and 44. At the same time, Chimer B29 starts. The timer B29 is provided to stop energization of the heaters 43 and 44, which are the heating devices of the water heater 1, to naturally cool the temperature of the hot water in the tank before moving to the draining operation, and to prevent damage to the drainage equipment due to high-temperature water draining. It is a timer.

Therefore, the timer B29 can be replaced by temperature detection means that can close the contact when the temperature inside the tank decreases.

The timer B29 closes the time contact 29-1 after a predetermined set time has elapsed, energizes the relay 30, and closes the contact 3 connected to the closing terminal (c) of the electric water supply valve 37.
0-1 closes to close the water supply electric valve 37.

When the electric water supply valve 37 closes, the contact 37-1 built into the electric valve closes and the relay 32 is energized, which opens the opening terminal (o) of the electric drain valve 38.
The contact 32-1 connected to the drain motorized valve 3 closes.
8 is released.

When the electric drain valve 38 opens, the hot water in the tank of the water heater 1 is drained by gravity from the drain port 4, but at this time, it is subjected to atmospheric pressure from the air vent valve 5 and can be drained smoothly.

Simultaneously with the excitation of the relay 32, the timer E33
starts. The timer E33 is preset to a time necessary and sufficient for the electric drain valve 38 to open, and closes the contact 33-1 after a predetermined period of time has elapsed. The normally closed contact 38-2 is a switch that is built into the electric drain valve 38 and opens when it detects its opening. In other words, if the electric drain valve 38 does not operate to the open position due to motor coil breakage, foreign matter caught in the valve, etc. until the time set by the timer E33 has elapsed, the relay 35 is energized and the relay contact 35-
1 closes and the set coil (S) of the keep relay 16 is energized, and the contact 16-1 closes and the alarm lamp 17 is turned on. The alarm lamp 17 is turned off by pressing the reset switch 15 after removing the cause of the malfunction of the electric drain valve 38.

The normally closed contact 38-2 may be a switch built into the electric drain valve 38, or may be a contact provided at the drain port of the water heater 1 that opens and holds according to a preset flow rate of discharge water. It is also possible to substitute.

Effects of the Invention As described above, according to the present invention, with the simple configuration of the control device, situations in which hot water cannot be supplied due to failures in closing the electric drain valve or failures in the power supply to the heating device can be prevented during water supply operations. It also prevents deterioration of tank life due to accumulated water in the tank due to a failure to close the electric water supply valve or failure to open the electric discharge valve during draining operations.
By operating the electric drain valves at different times, it is possible to prevent water from flowing out due to a power outage during supply/drainage.

[Brief explanation of drawings]

Fig. 1 is a configuration diagram of a water heater that is an embodiment of the present invention, Fig. 2 is a circuit diagram of the control device, Fig. 3 is a flowchart for explaining the operation, and Fig. 4 is a diagram of a conventional water heater. The circuit diagram and FIG. 5 are flowcharts for explaining the same operation. 1... Water heater, 2... Hot water inlet, 3... Water inlet,
4...Drain port, 5...Air vent valve, 8...Water supply electric valve, 11...Drainage electric valve, 14...DC current source, 27...Timer D, 28...Sensor coil.

Claims (1)

[Claims] 1 A tank with a hot water inlet at the top and a water inlet and a drain at the bottom, a heating device that heats the water in the tank, an electric water supply valve at the water inlet, an electric drain valve at the drain outlet, and a water outlet at the water inlet. Equipped with an air vent valve,
At the time of hot water supply, a water supply delay means opens the water supply valve after the electric drain valve closes, an energization delay means energizes the heating device after a predetermined time after the water supply valve is opened, and a energization delay means that stops energization to the heating device for a predetermined time. A cooling delay means that later enters the drain operation, a drain delay means that first closes the electric water supply valve and then opens the electric drain valve during the drain operation, a timer that confirms that the electric drain valve is opened within a predetermined time, and a timer that confirms that the electric drain valve is opened within a predetermined time, and during the drain operation. , when the time required to open the drain valve is longer than a predetermined value, and when the current detection device detects the energization of the heating device and the sensor coil, the current detection device does not detect the current after the set time of the energization delay means. Each water heater is equipped with an alarm device that issues an alarm when the situation occurs.