JP4100355B2 - Hot water storage water heater - Google Patents

Description

  The present invention relates to a hot water storage type hot water supply apparatus including a hot water storage tank for storing a heat storage fluid and a heating means for heating the heat storage fluid in the hot water storage tank, and particularly to the heating means, the circulation circuit, and the hot water storage tank. It relates to the filling of the heat storage fluid.

  Conventionally, as this kind of hot water storage type hot water supply apparatus, for example, a hot water supply system as shown in Patent Document 1 is known. In this hot water storage type hot water supply apparatus, as shown in FIG. 5, the hot water storage tank 100 that stores the heat storage fluid therein, and the fluid heating that sends the lowermost heat storage fluid in the hot water storage tank 100 to the uppermost portion in the hot water storage tank 100. Flow path 110, heating means 120 provided in the fluid heating flow path 110 for heating the heat storage fluid flowing through the fluid heating flow path 110, and a first flow through which the heat storage fluid in the hot water storage tank 100 flows. Portion 130a and second circulation portion 130b through which hot water supply water circulates are provided adjacent to each other, and the heat storage fluid and hot water supply water are configured to face each other and heat exchange is performed between them. 130, a circulation passage 140 for taking out the heat storage fluid heated from the upper part of the hot water storage tank 100, passing it through the first circulation part 130a, and then returning it to the lower part of the hot water storage tank 100, and this circulation passage 140 A pump means 150 for circulating the heat storage fluid, and a flow control means 160 for controlling the flow rate of the heat storage fluid flowing through the first flowing part 130a through the circulation passage 140.

  Then, by controlling the flow rate of the heat storage fluid flowing in the first circulation part 130a using the counter-flow hot water supply heat exchanger 130, the hot water temperature of the heat storage fluid after passing through the first circulation part 130a is reduced. It can be reduced to near the temperature of hot water before heating. As a result, it is possible to minimize heat loss at the time of heat exchange between the heat storage fluid and hot water supply water, thereby realizing an efficient hot water supply system.

In addition, according to this configuration, the heat storage fluid can be stored without applying a large pressure in the hot water storage tank 100, so that the open air type hot water storage in which the air hole 100a opening to the atmosphere is provided in the upper part of the hot water storage tank 100. The tank 100 can be formed (for example, refer to Patent Document 1).
JP 2001-153458 A

  However, when the hot water storage tank 100 open to the atmosphere as in Patent Document 1 and the heating means 120 are combined to fill the heat storage fluid into the empty hot water storage tank 100, generally, There is a method of supplying more heat storage fluid and filling the hot water storage tank 100. In this method, even if the hot water storage tank 100 is full, an air lock phenomenon may occur in which air stays in the piping path configured by the heating unit 120 and the fluid heating channel 110. In particular, when the heating means 120 is installed above the hot water storage tank 100, the above-described air lock phenomenon may occur remarkably in the fluid heating channel 110. Thereby, there is a problem that the heat storage fluid is not distributed to the heating means 120.

  Therefore, the piping path of the fluid heating flow path 110 is formed so that air in the path can be vented toward the air hole 100a of the hot water storage tank 100, or air is accumulated in the middle of the piping path. The location corresponds to a structure in which air does not stay in the path by providing an air vent valve or the like for discharging the air at the location to the outside. Therefore, in order to design and construct the piping path of the fluid heating flow path 110, there is a problem that design construction by an engineer having specialized technical skills is required, and the construction cost for constructing the apparatus is expensive.

  In view of the above, the object of the present invention is to prevent the occurrence of an air lock phenomenon by supplying the heat storage fluid so that the heating means and the hot water storage tank are pumped in this order from the fluid heating flow path. Another object of the present invention is to provide a hot water storage type hot water supply device that can be filled easily.

In order to achieve the above object, the following technical means are adopted. That is, in the invention described in claim 1, the hot water storage tank (10) for storing the heat storage fluid therein, the heating means (20) for heating the heat storage fluid in the hot water storage tank (10), and the hot water storage tank ( 10) Take out the heat storage fluid from the lower part in the inside, and return the heat storage fluid heated by the heating means (20) to the upper part in the hot water storage tank (10). In the hot water storage type hot water supply device comprising the return side circuit (23),
When the hot water storage tank (10) is filled with the heat storage fluid in the forward circuit (22) or the return circuit (23), either the forward circuit (22) or the return circuit (23) is used. Supplying the heat storage fluid and pumping it to the heating means (20) side, and then filling the hot water storage tank (10) side,
Heat storage fluid supply means (61, 62) for supplying heat storage fluid to either the forward circuit (22) or the return circuit (23) is provided, and the heat storage fluid supply means (61, 62) The heat storage fluid is supplied to the heating means (20) when the hot water storage tank (10) is filled with the heat storage fluid.
The heat storage fluid supply means (61, 62) communicates the supply circuit (61) for supplying heat storage fluid with the heating means (20) and the lower part of the hot water storage tank (10), or the heating means (20). And a switching valve (62) that switches the flow direction to one of the communication circuit and the supply circuit (61) . The heat storage fluid supply means (61, 62) includes an upstream end of the supply circuit (61). The heat storage agent supply means (60) which supplies a heat storage agent to a supply circuit (61) is provided while being connected to a water supply source .

  According to the first aspect of the present invention, for example, the air in the piping path on the heating means (20) side is stored in hot water by causing the heat storage fluid to be pumped from the heating means (20) side by water pressure or pumping means. Since it is sent to the tank (10) side, there is no occurrence of an air lock phenomenon in the piping path, and the filling operation of the heat storage fluid can be facilitated.

Specifically, when the heat storage fluid is filled into the hot water storage tank (10), the heat storage fluid is supplied to the heating means (20) side, whereby the heat storage fluid is heated by the heating means ( 20) Since it is sent into the hot water storage tank (10) so as to send out air in the piping path on the side, there is no occurrence of an air lock phenomenon in the piping path, and filling work can be facilitated.

By providing the supply circuit (61) and the switching valve (62), the heat storage fluid can be supplied from the supply circuit (61) to the hot water storage tank (10) after passing through the heating means (20) side. .

Moreover , by connecting the supply circuit (61) to the water supply source, it can be easily pumped to the heating means (20) side at the time of filling with water pressure. Thereby, the filling operation | work of the fluid for thermal storage can be performed easily.

In the invention according to claim 2 , the heat storage fluid supply means (61, 62) includes, in the supply circuit (61), the storage container (60a) for storing the heat storage fluid, and the heat storage fluid in the storage container (60a). By providing the pumping means (24a) for pumping the fluid to the outside, for example , the pumping means (24a) such as a pump can be easily pumped to the heating means (20) side during filling.

In the invention according to claim 3 , the forward circuit (22) is provided with a pressure feeding means (24) for sucking the heat storage fluid in the hot water storage tank (10) and pumping it to the heating means (20). The fluid supply means (61, 62) is provided in the vicinity of the upstream side of the pressure feeding means (24). According to the third aspect of the present invention, the heat storage fluid supply means (61, 62) is provided with the pressure feeding means (24a) in the above-mentioned second aspect , but is used when heating is performed by the heating means (20). The pumping means (24) may be used when filling the heat storage fluid. According to this, the pumping means (24a) used only at the time of filling becomes unnecessary.

The invention according to claim 4 is characterized in that the hot water storage tank (10) is configured to be at atmospheric pressure or extremely low pressure (for example, 10 kPa). According to the invention of claim 4, conventional high pressure (e.g., 170 kPa) for pressure-resistant design, such as a tank is not needed, can be a hot water storage tank itself is molded by resin. In this case, a press process and a welding process that are generally required for stainless steel processing are not required, and the manufacturing cost can be kept lower than before. Further, unlike the high-pressure tank, it is not necessary to form a cylindrical shape from the viewpoint of pressure resistance, and the degree of freedom in designing the tank shape can be increased.

In the invention according to claim 5 , the heating means (20) is a supercritical heat pump cycle in which the high-pressure side pressure of the refrigerant is equal to or higher than the critical pressure, and heats the heat storage fluid with the refrigerant whose pressure is increased to the critical pressure or higher. It is characterized by.

According to the fifth aspect of the present invention, in the supercritical heat pump type heating means (20) using a refrigerant such as carbon dioxide, the boiling temperature is as high as about 90 to 95 ° C. Since the degree of generation of bubbles from the side is high, for example, it is preferable to make it easy to send bubbles or the like into the hot water storage tank (10) side in the heating means (20).

  In addition, the code | symbol in the bracket | parenthesis of each said means shows a corresponding relationship with the specific means of embodiment mentioned later.

(First embodiment)
Hereinafter, a hot water storage type hot water supply apparatus according to a first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a schematic diagram showing an overall configuration of a hot water storage type hot water supply apparatus to which the present invention is applied. The hot water storage type hot water supply apparatus of the present embodiment is used for general household use, and as shown in FIG. 1, a hot water storage tank 10 for storing a heat storage fluid therein, and a lowermost heat storage tank in the hot water storage tank 10. A fluid heating passage 21 for sending the working fluid to the uppermost part in the hot water storage tank 10, a heat pump unit 20 that is a heating means for heating the heat storage fluid flowing through the fluid heating passage 21, and heat storage in the hot water storage tank 10. The first circulation part 30a through which the working fluid circulates and the second circulation part 30b through which the hot water supply water circulates are provided adjacent to each other, and the heat storage fluid and the hot water supply water are configured to face each other. A hot water supply heat exchanger 30 for exchanging, and a circulation for returning the heat storage fluid in the hot water storage tank 10 to the lower part in the hot water storage tank 10 after circulating the heat storage fluid in the hot water heat exchanger 30 to the first flow part 30a side. Circuit 11 and heat exchange for hot water supply Water supply pipe 31 connected to the upstream side of the second flow part 30b of the water heater 30, hot water supply pipes 32 and 33 connected to the downstream side of the second flow part 30b, and control for controlling the operation of the hot water supply system The apparatus (hot water supply control part 41, heat source control part 42) etc. are comprised.

  The hot water storage tank 10 of the present embodiment is opened to the atmosphere through the air hole 10a, and the interior of the hot water storage tank 10 is maintained at atmospheric pressure. The hot water storage tank 10 is formed of, for example, a resin material and has a rectangular parallelepiped shape. Further, in order to reduce the heat stored in the heat storage fluid in the hot water storage tank 10 from being released into the atmosphere from the wall surface of the hot water storage tank 10, the outer periphery of the hot water storage tank 10 is covered with a heat insulating material such as glass wool or urethane. May be. The heat storage fluid used is a heat storage fluid in which the main component is water and preservatives, antifreezing agents, LLC, and the like are added as necessary. In addition to these, a heat storage material having a high specific heat may be encapsulated by a technique such as a microcapsule and dispersed in water, or may be made into a thriller and flowable.

  Further, on the outer wall surface of the hot water storage tank 10, a plurality of (seven in this example) hot water storage thermistors 55 which are water temperature sensors for detecting the amount of hot water stored in the heat storage fluid or the hot water storage temperature are arranged in the vertical direction (the hot water storage tank 10. Temperature information at each water level of the heat storage fluid filled in the hot water storage tank 10 is output to the hot water supply control unit 41 described later.

  Therefore, based on the temperature information from the plurality of hot water storage thermistors 55, the hot water supply control unit 41 and the hot water heated above the hot water storage tank 10 and the low temperature heat storage fluid before being heated below the hot water storage tank 10 Can be detected, and the hot water temperature of the heat storage fluid at each water level can be detected. Of the plurality of hot water storage thermistors 55, the hot water storage thermistor 55 provided at the uppermost part has a function of detecting the temperature of hot water discharged from the hot storage fluid.

  The heat pump unit 20 that heats the heat storage fluid uses a supercritical heat pump cycle in which, for example, carbon dioxide is used as a refrigerant so that the refrigerant pressure on the high-pressure side becomes equal to or higher than the critical pressure of the refrigerant. As is well known, this heat pump cycle includes refrigeration cycle functional parts such as a compressor 25, a heat exchanger 26 for heating, an expansion valve 27, an evaporator 28, and an accumulator 29. Incidentally, the compressor 25 is driven by a built-in electric motor (not shown), and compresses and discharges the gas-phase refrigerant sucked from the accumulator 29 to a critical pressure or more.

  The heating heat exchanger 26 exchanges heat between the high-pressure refrigerant and the heat storage fluid. For example, the refrigerant passage 26a that is a primary side flow path through which the refrigerant flows and a heat storage that is a secondary side flow path through which the heat storage fluid flows. The counter flow type heat exchanger is configured such that the fluid passage 26b is provided in a double tube structure and the flow direction of the refrigerant and the flow direction of the heat storage fluid are opposed to each other. The expansion valve 27 decompresses the refrigerant flowing out of the heating heat exchanger 26 and supplies it to the evaporator 28. The evaporator 28 evaporates the refrigerant decompressed by the expansion valve 27 by heat exchange with the atmosphere. The accumulator 29 gas-liquid separates the refrigerant flowing out of the evaporator 28, causes only the gas-phase refrigerant to be sucked into the compressor 25, and stores surplus refrigerant in the cycle.

  The heat storage fluid passage 26b side of the heating heat exchanger 26 is connected to the hot water storage tank 10 via the fluid heating channel 21 described above. The fluid heating flow path 21 of the present embodiment is heated by the forward circuit 22 that takes out the heat storage fluid from the lower part 10 b in the hot water storage tank 10 and guides it to the heating heat exchanger 26, and the heating heat exchanger 26. The return side circuit 23 returns the heat storage fluid to the upper part 10 c in the hot water storage tank 10, and the circulation pump 24 is a pressure feeding means on the inlet side of the heating heat exchanger 26.

  The circulation pump 24 takes out the heat storage fluid from the lower part 10 b in the hot water storage tank 10 and supplies the heat storage fluid 26 heated by the heating heat exchanger 26 and the heating heat exchanger 26 to the upper part 10 c in the hot water storage tank 10. It is an electric pump for returning. Further, during the boiling operation, the boiling temperature of the heat storage fluid is made constant based on the hot water storage temperature detected by the hot water storage thermistor 55 provided at the uppermost part of the hot water storage tank 10 by the heat source control unit 42 described later. Thus, the rotation speed is controlled. As a result, the high-temperature heat storage fluid heat-exchanged by the heating heat exchanger 26 is sent into the hot water storage tank 10. Then, heat is sequentially stored in the heat storage fluid from the upper side to the lower side in the hot water storage tank 10.

  Further, the forward circuit 22 is provided with a switching valve 62 for switching the flow direction. The switching valve 62 is normally controlled by the heat source controller 42 described later so that the heat storage fluid passage 26 b side of the heating heat exchanger 26 and the lower portion 10 b of the hot water tank 10 communicate with each other. When filling the heat storage fluid, the heat storage fluid passage 26b side and the supply circuit 61 are controlled to communicate with each other. Further, the upstream end of the supply circuit 61 is connected to a water supply source via a gate valve (not shown), and further, a heat storage agent supply means 60 is provided in the middle of the supply circuit 61.

  The heat storage agent supply means 60 is a supply device that supplies the above-mentioned preservative, antifreezing agent, LLC or the like heat storage agent to tap water. When the hot water storage tank 10 is filled with a heat storage fluid, the switching valve 62 is provided. When the flow direction is switched to the heat storage fluid passage 26 b side and the heat storage agent supply means 60 is opened, a predetermined amount of heat storage agent is supplied to the tap water in the supply circuit 61.

  As a result, the heat storage fluid is supplied from the supply circuit 61 to the forward circuit 22 via the switching valve 62, is pumped to the heat storage fluid passage 26 b side, and is charged into the hot water storage tank 10 from the return circuit 23. Here, the switching valve 62 and the supply circuit 61 described above are heat storage fluid supply means referred to in the claims. In the present embodiment, the heat storage fluid is refreshed by supplying a predetermined amount of the heat storage agent to the tap water by the heat storage agent supply means 60. However, only the tap water may be used without adding the heat storage agent. However, when using only tap water, it is necessary to prevent problems caused by freezing of the heat storage fluid during the winter season.

  The heat pump unit 20 is operated by a control signal from a heat source control unit 42 to be described later, and outputs an operating state to the heat source control unit 42. In addition, the AC power is used as the power source, and the heat storage operation for boiling the heat storage fluid in the hot water storage tank 10 is performed mainly using the midnight power in the midnight time zone where the rate setting is the cheapest. Even in the belt, when the hot water temperature of the heat storage fluid decreases, the boiling operation is controlled. Incidentally, according to the supercritical heat pump cycle, a heat storage fluid having a temperature higher than that of a general heat pump cycle (for example, 85 to 90 ° C.) can be stored therein.

  Next, the circulation circuit 11 distributes the heat storage fluid in the hot water storage tank 10 to the first flow part 30a of the hot water supply heat exchanger 30, and the heat storage fluid heat-exchanged by the hot water supply heat exchanger 30 is stored in the hot water storage tank. 10 is a circulation circuit for returning to the lower part 10e in the high-temperature take-out pipe 12, the medium-temperature take-out pipe 13, the forward pipe 14, the return pipe 15, the high-medium temperature mixing valve 16 serving as the flow rate adjusting means, and the first circulation pump. 17.

  The high-temperature take-out pipe 12 is a pipe for taking out a high-temperature heat storage fluid among the heat storage fluid stored in the hot water storage tank 10, and an upstream end is connected to an upper portion 10 d in the hot water storage tank 10. The medium temperature take-out pipe 13 is a pipe for taking out the medium temperature heat storage fluid having a lower temperature than the high temperature heat storage fluid among the heat storage fluid stored in the hot water storage tank 10. The upstream end 10f is connected between 10d and the lower part 10e.

  The upstream pipe 14 has an upstream end connected to an outlet side of a high / medium temperature mixing valve 16 described later, and a downstream end connected to an upstream end of the first circulation part 30 a of the hot water supply heat exchanger 30. The return pipe 15 has an upstream end connected to the upstream end of the first circulation part 30 a and a downstream end connected to the lower part 10 e in the hot water storage tank 10. The forward pipe 14 is provided with a thermistor 54 before heat exchange, which is a pre-heat exchange water temperature sensor for detecting the hot water temperature of the heat storage fluid to be circulated through the first flow part 30a of the hot water supply heat exchanger 30. The temperature information in 14 is output to a hot water supply control unit 41 described later.

  Next, the high / medium temperature mixing valve 16 is provided at a downstream junction of the high temperature take-out pipe 12 and the intermediate temperature take-out pipe 13 and is a hot water temperature of a heat storage fluid that is circulated to the first flow part 30a of the hot water supply heat exchanger 30. The mixing ratio of the high-temperature heat storage fluid taken out from the high-temperature take-out pipe 12 and the medium-temperature heat storage fluid taken out from the medium-temperature take-out pipe 13 is adjusted by adjusting the ratio of the respective opening areas. I try to adjust it.

  The high / medium temperature mixing valve 16 is electrically connected to a hot water supply control unit 41 described later, and is controlled based on the temperature information of the heat storage fluid detected by the hot water storage thermistor 55 and the thermistor 54 before heat exchange. Is done. Incidentally, in this embodiment, when the hot water temperature of the heat storage fluid detected by the hot water storage thermistor 55 (in the vicinity of the intermediate temperature extraction pipe 13) is lower than a predetermined temperature (for example, 30 ° C.), the high temperature extracted from the high temperature extraction pipe 12 is high. The heat storage fluid is controlled to flow to the first flow part 30a.

  On the other hand, when the hot water temperature of the heat storage fluid detected by the hot water storage thermistor 55 (in the vicinity of the intermediate temperature extraction pipe 13) is equal to or higher than a predetermined temperature (for example, 30 ° C.), Control is performed so that both the medium-temperature heat storage fluid taken out from the medium-temperature take-out pipe 13 and the high-temperature heat storage fluid taken out from the high-temperature take-out pipe 12 are mixed and distributed to the first flow part 30a.

  Furthermore, the high / medium temperature mixing valve 16 adjusts the temperature of the hot water of the heat storage fluid flowing through the first flow portion 30a detected by the thermistor 54 before heat exchange so as to be equal to or higher than a predetermined temperature, thereby adjusting the second flow portion 30b. The hot-water supply water that flows through the water is prevented from becoming below a predetermined temperature (for example, about a set temperature + 5 ° C.). Thus, more medium temperature heat storage fluid in the vicinity of a predetermined temperature (for example, 30 ° C.) than the high temperature heat storage fluid is circulated to the first flow part 30a. Further, the high / medium temperature mixing valve 16 performs feedback control based on the hot water temperature of the heat storage fluid before heat exchange detected by the thermistor 54 before heat exchange.

  The first circulation pump 17 is arranged in the middle of the return pipe 15 and is a pump for circulating the heat storage fluid in the hot water storage tank 10 to the hot water supply heat exchanger 30. And hot water supply control mentioned later so that a rotation speed is controlled based on the hot water temperature of the hot water for hot water exchanged from the 2nd circulation part 30b of the heat exchanger 30 for hot water supply detected by the thermistor 52 after heat exchange mentioned later. The unit 41 is electrically connected. The circulation circuit 11 and the fluid heating passage 21 are provided with drain plugs 18 so that the heat storage fluid in the hot water storage tank 10 and the circulation circuit 11 can be drained manually if necessary. ing.

  Next, the hot water supply heat exchanger 30 is connected to the circulation circuit 11 so that the heat storage fluid in the hot water storage tank 10 flows, and the second water supply pipe 31 and the second hot water supply pipe 32 are connected to the hot water supply pipe 32. It has a circulation part 30b and is arranged in the vertical direction outside the hot water storage tank 10. The downstream end of the first circulation part 30 a is connected to the return pipe 15 so as to communicate with the lower part 10 d of the hot water storage tank 10, and the upstream end of the first circulation part 30 a is connected to the forward pipe 14.

  On the other hand, as for the 2nd circulation part 30b, the upstream end is connected to the piping 31 for water supply, and the downstream end is connected to the piping 32 for hot water supply. Therefore, as shown by the arrow in FIG. 1, the hot water supply heat exchanger 30 flows in the flow direction of the heat storage fluid flowing from the top to the bottom through the first circulation part 30 a and the second circulation part 30 b from the bottom to the top. It is a counterflow type heat exchanger with which the flow direction of the hot water for water which flows toward opposes.

  Further, the upstream of the water supply pipe 31 is connected to a water pipe so that the tap water is led to the second circulation part 30b. Note that a water supply thermistor 51 is provided in the water supply pipe 31 so that temperature information of tap water is output to a hot water supply control unit 41 described later. Further, the hot water supply pipe 32 has a flow rate adjusting valve 34 for adjusting the flow rate of the hot water supplied by the second circulation part 30 b, and a hot water supply at a junction of the downstream end of the hot water supply pipe 32 and the water supply pipe 31. A hot water supply mixing valve 35 serving as temperature adjusting means is provided. A hot water supply pipe 33 is connected to the outlet side of the hot water supply mixing valve 35.

  The hot water supply pipe 33 is a hot water supply pipe that leads to a hot water tap (not shown) such as a kitchen or bathroom. A hot water supply thermistor 53 and a flow rate counter 58 are provided in the middle thereof. The hot water supply thermistor 53 provides temperature information in the hot water supply pipe 33, and the flow rate counter 58 provides flow information in the hot water supply pipe 33 to the hot water supply control unit 41 described later. I am trying to output. The hot water supply pipe 32 is provided with a post-heat exchange thermistor 52 that detects the hot water temperature of the heat storage fluid heat-exchanged by the hot water supply heat exchanger 30, and temperature information in the hot water supply pipe 33 is described later. The data is output to the control unit 41.

  The flow rate adjustment valve 34 is a valve that adjusts the flow rate that flows through the second flow unit 30b, and is controlled by a hot water supply control unit 41, which will be described later, so that the flow rate that flows through the second flow unit 30b is less than or equal to a predetermined flow rate. That is, control is performed based on the hot water temperature of the hot water detected by the thermistor 52 after heat exchange so that the flow rate does not become excessive due to variations in the water pressure of the supplied water and the pressure loss in the hot water supply path.

  Next, the hot water supply mixing valve 35 is a temperature adjustment valve that adjusts the hot water temperature of the hot water to be discharged from the hot water supply pipe 33, and heat exchange is performed in the second circulation part 30b by adjusting the ratio of the respective opening areas. Control is performed to adjust the mixing ratio of the supplied hot water and tap water to the set temperature. The hot-water supply mixing valve 35 is electrically connected to a hot-water supply control unit 41, which will be described later. The hot-water supply water temperature information detected by the hot-water supply thermistor 51, the post-heat exchange thermistor 52, and the hot-water supply thermistor 53 is used. Controlled based on.

  Incidentally, the hot water temperature of the hot water supplied by the second circulation part 30b that is circulated to the hot water mixing valve 35 is set to, for example, about a set temperature + 5 ° C. That is, the flow rate circulating in the circulation circuit 11 and the hot water temperature of the heat storage fluid detected by the thermistor 54 before heat exchange are controlled. The hot water supply mixing valve 35 performs feedback control based on the hot water temperature of hot water supply water detected by the hot water supply thermistor 53.

  Next, the hot water supply control unit 41 is mainly composed of a microcomputer, and a built-in ROM (not shown) is provided with a preset control program, and temperature information from the thermistors 51 to 55, Based on the flow rate information from the flow rate counter 58 and an operation signal from an operation switch provided on an operation panel (not shown), the first circulation pump 17, the high / medium temperature mixing valve 16, the flow rate adjusting valve 34, the hot water supply mixing valve 35, etc. The circulation circuit 11 and the hot water supply pipes 32 and 33 are configured to control the actuators.

  Similarly to the hot water supply control unit 41, the heat source control unit 42 is mainly composed of a microcomputer, and a built-in ROM (not shown) is provided with a preset control program, not shown. The actuators in the heat pump unit 20 are controlled based on temperature information from various thermistors. In this heat source control unit 42, in order to keep the hot water temperature of the heat storage fluid heated by the heating heat exchanger 26 at a constant temperature, detection of a hot water storage thermistor (topmost portion) 55 that detects the temperature of the heat storage fluid after heating is performed. The rotational speed of the circulation pump 24 is controlled based on the temperature.

  Furthermore, when the heat storage fluid in the hot water storage tank 10 is heated by the heat source control unit 42, the heat storage fluid passage 26b side and the lower part 10b of the hot water storage tank 10 are set in a flow direction so as to communicate with each other. When the heat storage fluid is filled in the tank 10, the flow direction of the switching valve 62 is controlled to be switched to the side where the heat storage fluid passage 26 b and the supply circuit 61 communicate with each other.

  Next, the filling method of the heat storage fluid into the hot water storage tank 10 after the construction of the present apparatus will be described. First, a gate valve (not shown) provided at the upstream end of the supply circuit 61 is opened. Then, the switching valve 62 is switched in the flow direction in which the heat storage fluid passage 26b side and the supply circuit 61 communicate with each other. Then, the heat storage fluid is pumped from the forward side circuit 22 in the order of the heat storage fluid passage 26b, the return side circuit 23, and the upper part 10d of the hot water storage tank 10 to fill the hot water storage tank 10.

  In addition, since the heat storage fluid supplied from the supply circuit 61 to the outgoing circuit 22 is supplied to the supply circuit 61 by the heat storage agent supply means 60, tap water is generated as the heat storage fluid. As a result, the heat storage fluid is fed into the hot water storage tank 10 after passing through the heat pump unit 20 side from the forward circuit 22, so that the air during this time is sent to the hot water storage tank 10 side by the heat storage fluid and is exposed to the outside through the air hole 10 a. Discharged.

  Then, the heat storage agent supply means 60 supplies the heat storage agent until the heat storage fluid in the hot water storage tank 10 becomes full, and when full storage is detected, the switching valve 62 is connected to the heat storage fluid passage 26b side and the lower part 10b of the hot water storage tank 10. Is switched to the flow direction in which the heat storage agent communicates, and the supply of the heat storage agent from the heat storage agent supply means 60 is stopped. Thereby, the hot water storage tank 10 is filled with the heat storage fluid.

  And each heat pump cycle component in the heat pump unit 20 and the circulation pump 24 are operated, and the boiling operation of the heat storage fluid in the hot water storage tank 10 is executed. As a result, the heat storage fluid in the hot water storage tank 10 is introduced from the forward circuit 22 into the heat storage fluid passage 26b and exchanges heat with the high-pressure refrigerant, and the heat-exchanged high-temperature heat storage fluid is returned from the return circuit 23 to the hot water storage tank. 10 is stored in the heat storage fluid at a high temperature (for example, 85 ° C.).

  The hot water storage fluid stored in the hot water storage tank 10 is used as a heat source, and the heat storage fluid is circulated through the l-th circulation part 30a of the hot water supply heat exchanger 30 and circulated into the l-th circulation part 30a. Heat water is exchanged with hot water, and hot water for which hot water has been exchanged and tap water can be mixed to supply hot water to a hot water supply target area such as a kitchen, a washroom, and a bathtub. Incidentally, when the user opens a hot water tap (not shown) at the end of the hot water supply pipe 33, when the flow rate information is output to the hot water supply control unit 41 by the flow rate counter 58, first, the first circulation pump 17 is activated. To do. When the first circulation pump 17 is operated, the heat storage fluid in the hot water storage tank 10 is circulated to the first flow part 30 a of the hot water supply heat exchanger 30. Thereby, the hot water supply water which flows through the 2nd circulation part 30b of the hot water supply heat exchanger 30 receives the heat energy of the heat storage fluid and is heated.

  Here, the hot water supply control unit 41 drives the first circulation pump 17 so that the hot water temperature detected by the thermistor 52 after heat exchange becomes a predetermined temperature (for example, about a set temperature + 5 ° C.). ) To control. The hot and middle temperature mixing valve 16 controls the hot water temperature of the heat storage fluid detected by the pre-heat exchange thermistor 54 to be equal to or higher than a predetermined temperature. Specifically, when the hot water temperature of the heat storage fluid in the hot water storage tank 10 detected by the hot water storage thermistor 55 is lower than a predetermined temperature (for example, 30 ° C.), the hot water temperature is higher than the predetermined temperature extracted from the high temperature extraction pipe 12. The heat storage fluid is controlled to flow to the first flow part 30a.

  On the other hand, when the hot water temperature of the heat storage fluid in the hot water storage tank 10 detected by the hot water storage thermistor 55 is equal to or higher than a predetermined temperature (for example, 30 ° C.), the medium temperature heat storage fluid taken out from the intermediate temperature take-out pipe 13 or the medium temperature take-out Mixing both the medium-temperature heat storage fluid taken out from the pipe 13 and the high-temperature heat storage fluid taken out from the high-temperature take-out pipe 12 so that the heat storage fluid having a hot water temperature not lower than a predetermined temperature is circulated to the first flow part 30a. To be controlled.

  As a result, a large amount of medium-temperature heat storage fluid is circulated to the first flow part 30a, so that the low-temperature (for example, about the water supply temperature + 5 ° C.) heat storage fluid is returned to the lower part 10e in the hot water storage tank 10. . At this time, when the circulation of the medium temperature heat storage fluid is small, the temperature becomes higher than that of the low temperature heat storage fluid and returned to the hot water storage tank 10, but the heat storage fluid returned to the hot water storage tank 10 is returned. Over time, due to the difference in specific gravity of the heat storage fluid, a high temperature is formed upward, a low temperature is formed below, and an intermediate layer (medium temperature) is formed between the upper and lower portions.

  On the other hand, in the hot water supply mixing valve 35a, hot water supply water having a predetermined temperature (set temperature + about 5 ° C.) exchanged by the second circulation part 30b and water supplied from the water supply pipe 31 are mixed to reach the set temperature. The adjusted hot water supply water is discharged from the hot water supply pipe 33. With this hot water supply, the low-temperature (for example, about the water supply temperature + 5 ° C.) heat storage fluid is returned from the hot water supply heat exchanger 30 to the lower portion 10e in the hot water storage tank 10 via the return pipe 15.

  Accordingly, the heat storage fluid returned to the hot water storage tank 10 by discharging hot water from the hot water supply pipe 33 is heated to a higher temperature, lower to a lower temperature, and lower and higher due to the specific gravity difference of the heat storage fluid. It is divided into medium temperature layers and stored. That is, each time the hot water supply water is discharged, the boundary position between the hot water temperature that has been boiled and the cold water temperature that has not been boiled sequentially moves upward, and the amount of hot water stored in the hot water storage tank 10 decreases. .

  When the midnight time zone is reached, each heat pump cycle component in the heat pump unit 20 and the pressurized circulation pump 24 are operated to perform a heating operation of the heat storage fluid in the hot water storage tank 10 to perform a high temperature (for example, 85 ° C) for storing heat storage fluid. In the present embodiment, the heat storage fluid is supplied from the forward circuit 22, but the present invention is not limited to this, and as shown in FIG. 2, the switching valve 62 and the supply circuit 61 are provided in the middle of the return circuit 23. , And heat storage agent supply means 60 may be provided.

  In this case, the switching valve 62 is normally controlled so that the heat storage fluid passage 26b side of the heat exchanger 26 for heating and the upper portion 10c of the hot water storage tank 10 communicate with each other, and the hot water storage tank 10 is filled with the heat storage fluid. Is controlled so that the heat storage fluid passage 26b side communicates with the supply circuit 61.

  Thereby, since the heat storage fluid is sent into the hot water storage tank 10 after passing through the heat pump unit 20 side from the return side circuit 23, the air during this time is sent to the hot water storage tank 10 side by the heat storage fluid and is passed through the air hole 10 a to the outside. Discharged. In addition, in this embodiment, although comprised so that it might open | release to atmospheric pressure, you may comprise so that it may become a very low pressure (for example, 10 kPa), without limiting to this.

  According to the hot water storage type hot water supply apparatus of the first embodiment described above, when the hot water storage tank 10 is filled with the heat storage fluid, the heat storage fluid is supplied from the forward circuit 22 or the return circuit 23, and the heat pump unit 20. By being configured to fill the hot water storage tank 10 side after being pumped to the side, for example, by feeding the heat storage fluid from the heat pump unit 20 side with water pressure or the like, the forward circuit 22, the heat pump unit 20, Further, since the air in the return circuit 23 is sent to the hot water storage tank 10 side, there is no occurrence of an air lock phenomenon in the piping path, and the heat storage fluid filling operation can be facilitated.

  Specifically, the hot water storage tank 10 is configured such that the heat storage fluid sends out air on the heat pump unit 20 side by being configured by a supply circuit 61 that supplies the heat storage fluid and a switching valve 62 that switches the flow direction. Since it is fed into the pipe, there is no occurrence of an air lock phenomenon in the piping path, and the filling operation can be facilitated.

  In addition, the upstream end of the supply circuit 61 is connected to a water supply source, and the supply circuit 61 is provided with a heat storage agent supply means 60 for supplying a heat storage agent. Can be easily done. Thereby, the filling operation | work of the fluid for thermal storage can be performed easily.

  In addition, since the hot water storage tank 10 is configured to be at atmospheric pressure or extremely low pressure, a pressure resistance design like a conventional high pressure (for example, 170 kPa) tank is unnecessary, and therefore the hot water storage tank itself is formed of resin. Can do. In this case, a press process and a welding process that are generally required for stainless steel processing are not required, and the manufacturing cost can be kept lower than before. Further, unlike the high-pressure tank, it is not necessary to form a cylindrical shape in terms of pressure resistance, and the degree of freedom in designing the tank shape can be increased.

  The heat pump unit 20 is a supercritical heat pump cycle in which the high-pressure side pressure of the refrigerant becomes equal to or higher than the critical pressure, and the heat storage fluid is heated by the refrigerant whose pressure has been increased to the critical pressure or higher, thereby In the heat pump unit 20 of the critical heat pump system, since the boiling temperature is as high as about 90 to 95 ° C., the generation of bubbles from the heat storage fluid side is high. It is preferable to make it easy to feed to the 10 side.

(Second Embodiment)
In the above first embodiment, the heat storage agent is supplied to the tap water flowing through the supply circuit 61 by the heat storage agent supply means 60 and the hot water storage tank 10 is filled with the heat storage fluid. However, the heat storage agent is not limited to this. Is a fluid heat storage agent, a storage container 60a that houses the fluid heat storage agent is connected to the upstream end of the supply circuit 61, and the fluid heat storage agent in the storage container 60a is used as the heat storage fluid to move the forward circuit 22 Alternatively, it may be supplied from either one of the return side circuits 23.

  However, in the present embodiment, as shown in FIG. 3, the supply circuit 61 is provided with a pumping pump 24 a that is a pumping unit for pumping the fluid heat storage agent from the storage container 60 a. When the hot water storage tank 10 is filled with the heat storage fluid, the switching valve 62 is switched to the flow direction in which the heat storage fluid passage 26b side and the supply circuit 61 communicate with each other as in the first embodiment, and the pressure feed pump 24a. The hot water storage tank 10 can be filled with a heat storage fluid after being pumped from the forward circuit 22 to the heat pump unit 20 side. Thereby, there exists an effect similar to 1st Embodiment.

  In addition, in this embodiment, although the pumping pump 24a which pumps a fluid heat storage agent into the hot water storage tank 10 from the storage container 60a was arrange | positioned, not only this but as shown in FIG. The circulating pump 24 may be provided in the vicinity of the switching valve 62, that is, on the downstream side of the switching valve 62, and the circulating pump 24 may be operated when the hot water storage tank 10 is filled with the heat storage fluid. According to this, the above-mentioned pumping means 24a used only at the time of filling can be dispensed with.

(Other embodiments)
In the above embodiment, the hot water storage tank 10 does not necessarily need to use a resin material, and may be formed of a metal material. Moreover, the shape of the hot water storage tank 10 may not be a rectangular parallelepiped shape but may be a cylindrical shape, for example. In addition, although the hot water storage tank 10 is formed in an open air type, a hot water storage tank having a sealed type structure may be used. In this case, however, parts for protecting the tank such as a pressure reducing valve and a pressure relief valve are required.

  In the above embodiment, the heat pump unit 20 using carbon dioxide as a refrigerant has been described as a heat source device. However, the present invention is not limited to this, and a general heat pump cycle using a refrigerant such as chlorofluorocarbon or alternative chlorofluorocarbon may be used.

It is a schematic diagram which shows the whole structure of the hot water storage type hot water supply apparatus in 1st Embodiment of this invention. It is a schematic diagram which shows the whole structure of the hot water storage type hot-water supply apparatus in the modification of 1st Embodiment of this invention. It is a schematic diagram which shows the whole structure of the hot water storage type hot water supply apparatus in 2nd Embodiment of this invention. It is a schematic diagram which shows the whole structure of the hot water storage type hot-water supply apparatus in the modification of 2nd Embodiment of this invention. It is a schematic diagram which shows the whole structure of the hot water storage type hot-water supply apparatus in a prior art.

Explanation of symbols

10 ... Hot water storage tank 20 ... Heat pump unit (heating means)
22 ... Outward side circuit 23 ... Return side circuit 24 ... Circulation pump (pressure feeding means)
60 ... Thermal storage agent supply means 60a ... Storage container 61 ... Supply circuit (heat storage fluid supply means)
62 ... Switching valve

Claims (5)

A hot water storage tank (10) for storing heat storage fluid therein;
Heating means (20) for heating the heat storage fluid in the hot water storage tank (10);
A forward circuit (22) for taking out the heat storage fluid from the lower part of the hot water storage tank (10) and leading it to the heating means (20);
In the hot water storage type hot water supply apparatus comprising a return side circuit (23) for returning the heat storage fluid heated by the heating means (20) to the upper part in the hot water storage tank (10),
When the hot water storage tank (10) is filled with the heat storage fluid in the forward circuit (22) or the return circuit (23), the forward circuit (22) or the return circuit (23). The heat storage fluid is supplied from any one of the above, and after being pumped to the heating means (20) side, the hot water storage tank (10) side is filled.
Thermal storage fluid supply means (61, 62) for supplying thermal storage fluid to either the forward circuit (22) or the return circuit (23) is provided,
The heat storage fluid supply means (61, 62) is configured to supply the heat storage fluid to the heating means (20) when the hot water storage tank (10) is filled with the heat storage fluid. ,
The heat storage fluid supply means (61, 62) communicates the supply circuit (61) for supplying heat storage fluid with the heating means (20) and the lower part of the hot water storage tank (10), or the heating is composed from a means (20) and said supply circuit (61) and switching valve for switching one flow direction or communicating (62),
In the heat storage fluid supply means (61, 62), the upstream end of the supply circuit (61) is connected to a water supply source, and the heat storage agent supply means (60) supplies the heat storage agent to the supply circuit (61). ) Is provided . A hot water storage type hot water supply apparatus. A hot water storage tank (10) for storing heat storage fluid therein;
Heating means (20) for heating the heat storage fluid in the hot water storage tank (10);
A forward circuit (22) for taking out the heat storage fluid from the lower part of the hot water storage tank (10) and leading it to the heating means (20);
In the hot water storage type hot water supply apparatus comprising a return side circuit (23) for returning the heat storage fluid heated by the heating means (20) to the upper part in the hot water storage tank (10),
When the hot water storage tank (10) is filled with the heat storage fluid in the forward circuit (22) or the return circuit (23), the forward circuit (22) or the return circuit (23). The heat storage fluid is supplied from any one of the above, and after being pumped to the heating means (20) side, the hot water storage tank (10) side is filled.
Thermal storage fluid supply means (61, 62) for supplying thermal storage fluid to either the forward circuit (22) or the return circuit (23) is provided,
The heat storage fluid supply means (61, 62) is configured to supply the heat storage fluid to the heating means (20) when the hot water storage tank (10) is filled with the heat storage fluid. ,
The heat storage fluid supply means (61, 62) communicates the supply circuit (61) for supplying heat storage fluid with the heating means (20) and the lower part of the hot water storage tank (10), or the heating A switching valve (62) for switching the flow direction to one of the means (20) and the supply circuit (61) communicating with each other;
The heat storage fluid supply means (61, 62) pressure-feeds to the supply circuit (61) the storage container (60a) for storing the heat storage fluid and the heat storage fluid in the storage container (60a) to the outside. A hot water storage type hot water supply apparatus , characterized in that a pressure feeding means (24a) is provided . The forward circuit (22) is provided with a pumping means (24) for sucking the heat storage fluid in the hot water storage tank (10) and pumping it to the heating means (20), and the heat storage fluid supply means (61 62) is provided in the vicinity of the upstream side of the pumping means (24), and the hot water storage type hot water supply device according to claim 1 or 2 . The hot water storage hot water supply apparatus according to any one of claims 1 to 3, wherein the hot water storage tank (10) is configured to be at atmospheric pressure or extremely low pressure. The said heating means (20) is a supercritical heat pump cycle in which the high-pressure side pressure of the refrigerant is equal to or higher than the critical pressure, and heats the heat storage fluid with the refrigerant whose pressure is increased to the critical pressure or higher. The hot water storage type hot water supply device according to any one of claims 4 to 4.

Images