JP4990094B2 - Electric water heater - Google Patents

Description

  The present invention relates to an electric water heater, and more particularly to an electric water heater that can significantly reduce the time required for hot water in a bathtub.

  As a conventional electric water heater, for example, as disclosed in Patent Document 1, a first hot water beam circuit that supplies hot water from a hot water storage tank to a bathtub is provided, and the hot water is indirectly heated by the hot water from the hot water storage tank. Some have a heat exchanger for hot water supply.

  This electric water heater is equipped with a heat exchanger for hot water supply that indirectly heats the tap water in the water supply pipe with the hot water in the hot water storage tank. The heat is returned to the lower part of the tank through the primary side of the heat exchanger, and tap water is passed through the secondary side of the hot water supply heat exchanger and heated to a predetermined temperature.

JP 2007-40566 A

  However, in the conventional electric water heater, the hot water in the bathtub is performed by an independent operation of the first hot water circuit that supplies the hot water in the hot water storage tank to the bathtub. For this reason, in the conventional electric water heater, for example, a hot water beam of 42 ° C. and 200 L requires a relatively long time of about 20 minutes.

  Therefore, an object of the present invention is to provide an electric water heater that can significantly reduce the time required for hot water in a bathtub.

  As a means for solving the above-mentioned problems, the present invention provides a first hot water circuit for supplying hot water from a hot water storage tank to a bathtub, heat exchange between the hot water and the hot water in the hot water tank, and indirectly heating the supplied water. An electric water heater comprising a hot water supply heat exchanger for generating hot water supply, wherein the second hot water beam is supplied in parallel with the first hot water circuit to supply the hot water generated by the hot water heat exchanger to the bathtub. An electric water heater comprising a circuit.

According to such an electric water heater, the hot water generated by the hot water heat exchanger can be supplied to the bathtub by the second hot water beam circuit. That is, the hot water generated in the hot water heat exchanger can be supplied to the bathtub by the second hot water circuit while the hot water in the hot water storage tank is supplied to the bathtub by the first hot water circuit.
Thereby, the time required for hot water in the bathtub can be greatly shortened.

  ADVANTAGE OF THE INVENTION According to this invention, the electric water heater which can reduce significantly the time which the hot water of a bathtub requires can be provided.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 to 6.

≪Configuration of electric water heater≫
As shown in FIG. 1, an electric water heater 1 according to this embodiment includes a hot water storage tank 10 that stores hot water, a heat pump circuit 20 that heats water in the hot water storage tank 10, and a water supply circuit 30 through which water (tap water) flows. And a first hot water beam circuit 40 for supplying hot water from the hot water storage tank 10 to the tub B, and a hot water supply heat exchanger for exchanging heat between the hot water and the hot water in the hot water storage tank 10 to indirectly heat the hot water to generate hot water. 50, a hot water supply circuit 60 through which hot water flows, a reheating circuit 70 for replenishing the bath water stretched on the bathtub B, an operation unit 80 operated by a person for hot water filling, and the like. And a controller 90 (control device).

<Hot water storage tank>
The hot water storage tank 10 is supplied with water from a water supply circuit 30. The water in the hot water storage tank 10 is heated by the heat pump circuit 20 to become hot water, and then stored in the hot water storage tank 10. The temperature of water (hot water) in the hot water storage tank 10 is higher as it goes vertically upward, and is, for example, about 90 ° C. at the upper part of the hot water storage tank 10 and about 50 ° C. at the intermediate part. In addition, the warm water in an intermediate part is called medium warm water.

  In the hot water storage tank 10, a plurality of temperature sensors 11 are arranged in the vertical direction (four in FIG. 1). The temperature sensor 11 detects the temperature of water (hot water) in the hot water storage tank 10, and the controller 90. To output.

<Heat pump circuit>
The heat pump circuit 20 is a circuit that heats the water in the hot water storage tank 10, and includes a heat pump 21 and a circulation pump 26 that circulates the water in the hot water storage tank 10.
The heat pump 21 is a device (heat pump) that circulates while compressing and expanding a refrigerant such as carbon dioxide, and is a device that heats the water in the hot water storage tank 10 that is circulated by the refrigerant whose temperature has been increased by being compressed. Such a heat pump 21 heats the water in the circulating hot water storage tank 10 by exchanging heat between the compressor 22 that compresses the refrigerant and the refrigerant heated by the compression and the water in the circulating hot water storage tank 10. A heat exchanger 23 for reducing the pressure of the refrigerant, and a heat absorber 25 for absorbing heat from the outside air to the refrigerant whose temperature has been reduced by the pressure reduction.

  On the other hand, when the circulation pump 26 is activated, water in the lower part of the hot water storage tank 10 is sucked, pumped to the heat exchanger 23, heated in the heat exchanger 23, and then returned to the upper part of the hot water storage tank 10. Yes.

<Water supply circuit>
The water supply circuit 30 is a circuit through which water (tap water) from an external water supply source flows. The water supply is supplied to the lower part of the hot water storage tank 10 from the water supply pipe 30a through the pipe 30b, the pressure reducing valve 31 for reducing the water supply pressure, and the pipe 30c.

  Further, the water supply is supplied from the middle of the pipe 30 c to the second mixing valve 42 of the first hot water circuit 40 through the pipe 30 d. That is, the water supplied through the pressure reducing valve 31 is mixed in the second mixing valve 42 with the hot water flowing through the first hot water circuit 40 and going to the bathtub B.

  Further, the water supply is supplied from the water supply pipe 30a to the hot water supply heat exchanger 50 through the pipe 30e. That is, the water supply that does not pass through the pressure reducing valve 31 is supplied to the hot water supply heat exchanger 50. Thereby, the injection pressure of the hot water supplied from the hot water supply device 64 described later is ensured.

<First hot water circuit>
The first hot water circuit 40 is a circuit for supplying hot water from the hot water storage tank 10 to the bathtub B and hot watering the bathtub B.
The hot hot water at the top of the hot water storage tank 10 is supplied to the first mixing valve 41 via the pipe 40a. Middle temperature warm water (medium temperature water) in the middle of the hot water storage tank 10 is supplied to the first mixing valve 41 via the pipe 40b. The first mixing valve 41 mixes high-temperature hot water from the pipe 40 a and medium-temperature hot water from the pipe 40 b at a mixing ratio according to a command from the controller 90.

  The hot water generated by being mixed by the first mixing valve 41 is supplied to the second mixing valve 42 via the pipe 40c. The second mixing valve 42 mixes hot water from the pipe 40 c and water supply from the pipe 30 d at a mixing ratio according to a command from the controller 90.

The hot water generated by being mixed by the second mixing valve 42 is supplied to the bathtub B through the pipe 40d, the normally closed on-off valve 43, and the pipe 40e.
The on-off valve 43 is set to be opened by the controller 90 when hot water is poured by the first hot water circuit 40. When the on-off valve 43 is opened, water with a predetermined pressure is introduced into the lower part of the hot water storage tank 10 via the pipe 30c, whereby hot water in the upper and intermediate parts of the hot water storage tank 10 is pushed out, The hot water generated by being mixed in order by the first mixing valve 41 and the second mixing valve 42 is supplied to the bathtub B.

Moreover, a part of warm water produced | generated by mixing by the 1st mixing valve 41 and the 2nd mixing valve 42 in order is the piping 70a, the pump 71 which operates at the time of reheating, the piping 70b, the direction switching valve 72, the piping 70d, It is supplied to the bathtub B through a part of the pipe 70c.
That is, the hot water generated by being mixed in order by the first mixing valve 41 and the second mixing valve 42 branches into two branches downstream of the on-off valve 43 and is supplied to the bathtub B in two systems. Yes. Thereby, the hot water filling time is shortened.

  Moreover, the temperature sensor 44 is arrange | positioned at the piping 40e, and the temperature sensor 44 detects the temperature (measured temperature T11) of the warm water which goes to the bathtub B, and outputs it to the controller 90. The controller 90 then adjusts the first mixing valve 41 and the second mixing so that the measured temperature T11 of the hot water detected by the temperature sensor 44 becomes the bath water temperature T1 (first set temperature) set by the operation unit 80. The mixing ratio in the valve 42 is controlled.

<Heat exchanger for hot water supply>
The hot water supply heat exchanger 50 is a device that heat-exchanges hot water and hot water in the hot water storage tank 10 and indirectly heats the hot water to generate hot water.
Specifically, the water supply introduced into the hot water supply heat exchanger 50 from the pipe 30e is heated from the middle of the pipe 40a by the hot water in the hot water storage tank 10 introduced through the pipe 50a to generate hot water supply. It is like that. The hot water from the hot water storage tank 10 after the heat exchange is returned to the lower part of the hot water storage tank 10 through the pipe 50b, a pump 51 that operates when a hot water supply is requested, the pipe 50c, and a part of the pipe 30c. ing.

  The pump 51 is configured such that the rotation speed is freely controlled by the controller 90 via an inverter circuit (not shown). Then, the controller 90 controls the pump 51 so that the hot water temperature (measured hot water temperature T12) detected by the temperature sensor 61 described later becomes the hot water temperature T2 (second set temperature) set by the operation unit 80. It is supposed to be. That is, the controller 90 is configured to increase the rotational speed of the pump 51 when the measured hot water temperature T12 detected by the temperature sensor 61 is lower than the set hot water temperature T2.

<Hot water supply circuit>
The hot water supply circuit 60 is a circuit through which hot water generated by the hot water supply heat exchanger 50 flows.
The hot water generated by the hot water supply heat exchanger 50 flows through the pipe 60a, the flow sensor 62, the pipe 60b, the cock 63 that is opened when there is a hot water supply request, and the pipe 60c, and is jetted from a hot water supply device 64 such as a shower. It has become. The flow rate sensor 62 detects the flow rate of hot water supplied to the hot water supply device 64 and outputs it to the controller 90.

  That is, when the controller 90 detects that the cock 63 is opened and the flow rate of hot water supplied to the hot water supply device 64 is greater than 0 (or a predetermined flow rate close to 0) via the flow rate sensor 62, the controller 90 It is configured to determine that there is a hot water supply request from the hot water supply device 64 (external).

  The temperature sensor 61 is arranged in the pipe 60a so as to detect the measured hot water supply temperature T12 immediately after being discharged from the hot water supply heat exchanger 50, and outputs the detected actual hot water supply temperature T12 to the controller 90. ing.

Further, hot water is supplied to the pipe 70c from the middle of the pipe 60a through the pipe 60d, the pressure reducing valve 65, the pipe 60e, the normally closed on-off valve 66 opened by the controller 90 when hot water is poured quickly, and the pipe 60f. It has come to be. That is, when hot water is generated in the hot water supply heat exchanger 50, when the on-off valve 66 is opened, hot water is supplied through the pipe 60d, the pressure reducing valve 65, the pipe 60e, the on-off valve 66, the pipe 60f, and the pipe 70c. Is supplied to the bathtub B.
In other words, in the present embodiment, the second hot water beam circuit that supplies the hot water generated by the hot water supply heat exchanger 50 to the bathtub B in parallel with the first hot water beam circuit 40 includes the pipe 60d, the pressure reducing valve 65, and the pipe. 60e, on-off valve 66, piping 60f, and a part of piping 70c are comprised.

<Turning circuit>
The chasing circuit 70 is a circuit for chasing the bath water stretched on the bathtub B.
At the time of reheating, the bath water is a part of the pipe 40e, the pipe 70a, a pump 71 that operates according to a command from the controller 90 at the time of reheating, a direction switching valve 72, and a part of which is routed through the inner upper part of the hot water storage tank 10. It returns to the bathtub B through 70c. The portion of the pipe 70c that passes through the inner upper portion of the hot water storage tank 10 is configured as a heat exchanging unit 73, and the bath water passing through the heat exchanging unit 73 is heated by the hot water in the hot water storage tank 10, and as a result, The bath water is chased away.

<Operation unit>
The operation unit 80 is a part that is arranged in a bathroom or kitchen and is operated by a person for hot water. The operation unit 80 includes a hot water button 81, a rush button 82, a chasing button 83, temperature control buttons 84 and 85, and a liquid crystal panel 86.

The hot water button 81 is pressed when the hot water is normally applied by using only the first hot water circuit 70 without using the second hot water circuit composed of the pipes 60d, 60e, 60f and the like. Switch.
The rush button 82 is used when supplying hot water to the tub B by using a second hot water circuit composed of the pipe 60d and the like simultaneously with hot water by the first hot water circuit 70 in order to hurry hot water. The switch to be pressed.
The chasing button 83 is a switch that is pressed when chasing water by the chasing circuit 70.

The temperature control button 84 is a switch for setting the temperature of warm water (boiled water) supplied from the first hot water circuit 70 to the bathtub B (flour water temperature T1, second set temperature).
The temperature adjustment button 85 is a switch for setting the temperature of hot water generated by the hot water supply heat exchanger 50 (hot water supply temperature T2, second set temperature).
The liquid crystal panel 86 is a portion that displays the set bath water temperature T1 and the hot water supply temperature T2.

  The operation unit 80 is connected to a controller 90. The controller 90 turns on / off signals of the hot water button 81, the rush button 82, and the reheating button 83, the set bath water temperature T1, and the hot water temperature T2. Is to be detected.

<Controller>
The controller 90 is a control device that electronically controls the electric water heater 1, and includes a CPU, a ROM, a RAM, various interfaces, an electronic circuit, and the like, and controls various devices according to programs stored therein. Control and execute various processes.

≪Operation and effect of electric water heater≫
Next, the operation and effect of the electric water heater 1 will be described.

<Hurry up the hot water beam-Combined use of the first hot water circuit and the second hot water circuit>
With reference to FIG. 2, the case where the rush button 82 is pushed and the 1st hot water circuit 40 and the 2nd hot water circuit comprised from the piping 60d etc. are used together and rushes to the bathtub B is demonstrated. To do.

[Hot water by the first hot water circuit]
The controller 90 that has detected the ON signal of the rush button 82 opens the on-off valve 43. If it does so, the water supply via the pressure-reduction valve 31 will enter into the lower part of the hot water storage tank 10, and the hot water of the hot water storage tank 10 will be extruded from piping 40a, 40b. Then, in the first mixing valve 41 and the second mixing valve 42, the measured temperature T11 of the hot water detected by the temperature sensor 44 becomes the bath water temperature T1 (first set temperature) set by the operation unit 80. After being mixed, it is supplied to bathtub B.

[Supplying hot water with the second hot water circuit]
In parallel with this, the controller 90 opens the on-off valve 66 and operates the pump 51. Then, hot water is heated by the hot water supply heat exchanger 50 to generate hot water, and the hot water is supplied to the bathtub B through a part of the pipes 60d, 60e, 60f and the pipe 70c.

  In this way, the hot water generated in the hot water heat exchanger 50 is supplied to the bathtub B while the hot water of the hot water storage tank 10 is applied to the bathtub B by the first hot water circuit 40, so the hot water of the bathtub B is supplied. The time required for this can be greatly reduced. Specifically, for example, a hot water beam of 42 ° C. and 200 L can be performed in a short time of 10 minutes or less.

[Restriction of hot water supply to bathtub B by the second hot water circuit]
When the first hot water circuit 40 and the second hot water circuit are used together, if the remaining amount of hot water in the hot water storage tank 10 becomes a predetermined amount or less, the controller 90 (operation restricting means) stops the pump 51 and opens and closes it. The valve 66 is closed, and the hot water supply operation to the bathtub B by the second hot water beam circuit for hot water supply is stopped. That is, the controller 90 limits the hot water supply operation to the bathtub B by the second hot water circuit according to the remaining hot water amount in the hot water storage tank 10.
More specifically, when the pump 51 is operated to generate hot water in the hot water supply heat exchanger 50, the hot water in the hot water storage tank 10 decreases. Therefore, even if there is a hot water supply request from the hot water supply device 64 after hot water filling, the hot water storage tank is used in the combined use of the first hot water circuit 40 and the second hot water circuit so that the hot water supply heat exchanger 50 can generate hot water. When the remaining amount of hot water of 10 becomes a predetermined amount or less, the hot water supply operation to the bathtub B by the second hot water beam circuit for hot water supply is stopped.
When the hot water in the hot water storage tank 10 is derived, the low temperature water in the hot water storage tank 10 gradually increases upward, and the hot water decreases, so the remaining amount of hot water in the hot water storage tank 10 is equal to the hot water storage tank 10. Are estimated by a plurality of temperature sensors 11 arranged in the vertical direction.

[Control of hot water temperature]
The controller 90 (temperature control means) includes a bath water temperature T1 (first set temperature of hot water supplied from the first hot water circuit 40 to the bathtub B) set by the operation unit 80, and a hot water supply heat exchanger. When the set hot water supply temperature T2 (second set temperature) of 50 is different, the measured hot water supply temperature T12 supplied to the bathtub B from the second hot water beam circuit becomes the set bath water temperature T1. The rotational speed of the pump 51 is controlled.
Specifically, when the set hot water supply temperature T2 is higher than the set bath water temperature T1, the controller 90 decreases the rotation speed of the pump 51.

<There is a hot water supply request when using the first hot water circuit and the second hot water circuit>
Next, referring to FIG. 3, when hot water is poured using the first hot water circuit 40 and the second hot water circuit simultaneously, the cock 63 is opened and there is a hot water request from the hot water supply device 64. Explain when.

  The controller 90 (operation switching means) that detects that hot water flows through the flow rate sensor 62 toward the hot water supply device 64 and has requested a hot water supply from the outside closes the on-off valve 66. Thereby, the supply operation to the bathtub B of the hot water supply by a 2nd hot water beam circuit is stopped. At the same time, the hot water supply is switched to be supplied to the hot water supply device 64 (external). As a result, it is possible to prevent the hot water flow rate of the hot water supply device 64 from being insufficient while continuing the hot water in the bathtub B.

<Hot water using only the first hot water circuit>
Next, referring to FIG. 4, a case where the hot water button 81 is pressed and only the first hot water circuit 40 is used for normal hot water will be described.

  The controller 90 that has detected the ON signal of the hot water button 81 opens the on-off valve 43 while keeping the on-off valve 66 closed. If it does so, the water supply via the pressure-reduction valve 31 will enter into the lower part of the hot water storage tank 10, and the hot water of the hot water storage tank 10 will be extruded from piping 40a, 40b. Then, in the first mixing valve 41 and the second mixing valve 42, the measured temperature T11 of the hot water detected by the temperature sensor 44 becomes the bath water temperature T1 (first set temperature) set by the operation unit 80. After being mixed, it is supplied to bathtub B.

  That is, the controller 90 (operation switching means) responds to the ON / OFF signal of the hot water button 81 and the rush button 82, and supplies hot water to the bathtub B by the first hot water circuit 40 and the second hot water. The first mode in which the hot water supply operation to the bathtub B by the beam circuit is simultaneously performed and the second mode in which only the hot water supply operation to the bathtub B by the first hot water circuit 40 alone are switched.

<Only hot water request>
Next, with reference to FIG. 5, a description will be given of a case where the cock 63 is opened and a hot water supply request is received from the hot water supply device 64 when the hot water button 81 and the rush button 82 are not pressed.

The controller 90 that has detected that there has been a hot water supply request via the flow sensor 62 operates the pump 51. Thereby, in the hot water supply heat exchanger 50, the hot water is heated and hot water is generated, and the hot water is ejected from the hot water supply device 64 through the pipe 60a and the like.
In this case, the controller 90 controls the rotation speed of the pump 51 so that the current measured hot water supply temperature T12 becomes the set hot water supply temperature T2.

<Courage>
Next, with reference to FIG. 6, the case where the reheating button 83 is pushed and the bath water stored in the bathtub B is repelled is demonstrated.

  The controller 90 that has detected the ON signal of the follow-up button 83 operates the pump 71 and controls the direction switching valve 72 so that the pipe 70b and the pipe 70c communicate with each other. Then, the bath water is circulated so as to pass through the heat exchange unit 73 in the hot water storage tank 10, and is heated when passing through the heat exchange unit 73. As a result, he is relegated.

The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and may be appropriately changed without departing from the spirit of the present invention.
In the above-described embodiment, the configuration in which the pipe 60f constituting the second hot water beam circuit joins the pipe 70d is exemplified. However, for example, the pipe 60f may be directly connected to the bathtub B.

It is a figure which shows the structure of the electric water heater which concerns on this embodiment. It is a figure which shows the condition where the rush button is pushed and the 1st hot water circuit and the 2nd hot water circuit are used together, and hot water is applied. It is a figure which shows the condition where there was a hot-water supply request | requirement from the outside at the time of using together a 1st hot water beam circuit and a 2nd hot water beam circuit. It is a figure which shows the condition where the hot water button is pushed and only the 1st hot water circuit is used, and hot water is usually poured. It is a figure which shows the condition where there was only the hot water supply request | requirement from the outside. It is a figure which shows a chasing situation.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electric water heater 10 Hot water storage tank 20 Heat pump circuit 26 Circulation pump 30a Water supply piping 31, 66 Pressure-reducing valve 40 1st hot water circuit 50 Hot water supply heat exchanger 60d-60f Piping (2nd hot water circuit)
80 Operation section 81 Hot water button 82 Hurry button 90 Controller B Bathtub T1 Bath water temperature (first set temperature)
T2 Hot water supply temperature (second set temperature)
T11 Current measured temperature of hot water (flow water) T12 Current measured hot water temperature

Claims (7)

A first hot water circuit for supplying hot water from the hot water storage tank to the bathtub;
Heat exchange between the hot water and the hot water in the hot water storage tank, and a hot water supply heat exchanger that indirectly heats the hot water to generate hot water;
An electric water heater comprising:
In parallel with the first hot water circuit, a second hot water circuit for supplying hot water generated by the hot water heat exchanger to the bathtub is provided ,
An electric water heater characterized in that the first hot water circuit and the second hot water circuit are used together to heat the bathtub . The hot water flowing through the first hot water beam circuit and going to the bathtub is mixed with water supplied via a pressure reducing valve,
2. The electric water heater according to claim 1, configured to supply water that does not pass through the pressure reducing valve to the heat exchanger for hot water supply. 3. The electric hot water supply according to claim 1, further comprising operation restriction means for restricting a hot water supply operation to the bathtub by the second hot water circuit according to a remaining hot water amount in the hot water storage tank. Machine. When the first set temperature of hot water supplied from the first hot water beam circuit to the bathtub is different from the second set temperature of hot water generated in the hot water supply heat exchanger,
The temperature control means which controls so that the temperature of the hot water supplied from the said 2nd hot water beam circuit to the said bathtub may turn into the said 1st setting temperature is provided. The any one of Claims 1-3 characterized by the above-mentioned. The electric water heater described in the paragraph. The operation switching means for switching between a hot water supply operation to the bathtub by the first hot water circuit and a hot water supply operation to the bathtub by the second hot water circuit is provided. Item 5. The electric water heater according to any one of items 4 to 5. When the hot water supply operation to the bathtub by the first hot water circuit and the hot water supply operation to the bathtub by the second hot water circuit are performed simultaneously,
When a hot water supply request is made from the outside,
The operation switching means which stops supply operation of hot water supply to the bathtub by the second hot water beam circuit and switches so that hot water is supplied to the outside is provided. The electric water heater described in the paragraph. A first mode for simultaneously performing a hot water supply operation to the bathtub by the first hot water circuit and a hot water supply operation to the bathtub by the second hot water circuit;
A second mode for performing only hot water supply operation to the bathtub by the first hot water circuit;
The electric hot water supply device according to any one of claims 1 to 4, further comprising an operation switching unit that switches between the two.

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