JP2012107822A - Hot water storage type water heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hot water storage type water heater device that is configured to use hot water in a hot water storage tank so that not only the decrease in an available amount of hot water due to the generation of intermediate temperature water but also the deterioration in the efficiency during heating are avoided while the increase in radiant heat loss due to convection flows in a pipe from which intermediate temperature water is taken out, is prevented.SOLUTION: The hot water storage type water heater device includes: the hot water storage tank 1; a first hot water feeding pipe 3 connected to the upper part of the hot water storage tank 1; a second hot water feeding pipe 4 arranged within the hot water heat storage tank 1, and having at least a water take-in part from which hot water is taken in from a substantially intermediate part of the hot water storage tank 1 in the height direction; and a mixing valve 6 for mixing the hot water from the first hot water feeding pipe 3 and the hot water from the second hot water feeding pipe 4.

Description

  The present invention relates to a hot water storage type hot water supply apparatus that stores hot water in a hot water storage tank.

  This type of hot water supply apparatus heats the water supplied from the bottom of the hot water tank to a high temperature by a heating means, and repeats a series of cycles to store it in the upper part of the hot water tank covered with a heat insulating material, thereby Or store hot water in a part. When the user uses hot water to supply hot water, the user mixes it with unheated water so as to obtain a predetermined temperature and use the hot water supply terminal.

  The operating efficiency of the heat pump heating means used here depends on the outside air temperature, the boiling temperature, and the incoming water temperature, which is the temperature of the water supplied to the heating means, and when the outside air temperature is high or the boiling temperature is low, Operation efficiency is improved when the incoming water temperature is low. The outside air temperature varies depending on the season and operation time, and in addition, the incoming water temperature also varies depending on the temperature state of the hot water tank.

  In particular, when using a terminal that uses the heat in the hot water tank such as a bath chase or a radiator, the hot water in the heat using terminal and the hot water in the hot water tank are exchanged with a heat exchanger. It is configured to return to.

  Originally, there is water at the bottom of the hot water tank at a temperature that is about the same as the water supply temperature. However, when the use of a heat terminal occurs, the hot water from the heat exchanger is mixed with the low water at the bottom. Therefore, intermediate temperature water having an intermediate temperature higher than the feed water temperature is generated in the lower part of the hot water tank. Since the medium-temperature water is supplied to the heating means at the time of boiling, the temperature of the incoming water rises and the efficiency is significantly reduced.

  Conventionally, in order to remove the medium temperature water generated by the heat utilization terminal, a second hot water outlet is provided at an intermediate position in the vertical direction of the hot water tank, and the hot water existing at the intermediate position is preferentially used (for example, , See Patent Document 1).

  FIG. 12 shows a conventional hot water supply apparatus described in Patent Document 1. As shown in FIG. As shown in FIG. 12, a hot water tank 1, a heating means 2 for heating the hot water in the hot water tank 1, a first outlet pipe 3 connected to the upper part of the hot water tank 1, and an intermediate portion of the hot water tank 1 Second hot water pipe 4 connected, first mixing valve 6 for mixing hot water from first hot water pipe 3 of hot water tank 1 and hot water from second hot water pipe 4, and second hot water pipe 4 is provided on the surface of the hot water storage tank at a position where 4 is connected, and a hot water temperature detecting means 12 for detecting the hot water temperature in the hot water tank 1 and a hot water temperature setting means 30 for setting the hot water temperature are provided. If the detected hot water temperature is equal to or higher than the hot water supply set temperature set by the hot water supply temperature setting means 30, the hot water is discharged from the second hot water discharge pipe 4, and if it is lower than the hot water supply set temperature, the hot water is discharged from the first hot water discharge pipe 3. The flow path of the first mixing valve 6 is switched.

  Moreover, the heat utilization terminal 23, the heat exchanger 20 for exchanging the heat of the hot water storage tank 1 and the heat in the heat utilization terminal 23, the heat utilization hot water discharge pipe 21 connected to the upper part of the hot water storage tank 1, and the heat exchanger 20 And a heat utilization return pipe 22 connected to the lower part of the hot water tank 1, a pump 25 for conveying hot water from the hot water tank 1 to the heat exchanger 20, and heat utilization for detecting the heat utilization temperature at the heat utilization terminal 23. The temperature detection means 24 and the heat use temperature setting means 31 for setting the use temperature at the heat use terminal 23 are provided, and when the heat use by the heat use terminal 23 occurs, the temperature detected by the heat use temperature detection means 24 The flow rate is controlled by controlling the pump 25 according to the temperature set by the heat utilization temperature setting means 31. The intermediate warm water returning from the heat utilization return pipe 22 enters from the lower part of the hot water storage tank 1, rises according to the use of hot water, and is used after being discharged from the second hot water discharge pipe 4.

JP 2003-240342 A

  However, when the temperature at the position of the second tapping pipe 4 is higher than the intermediate temperature (for example, 40 ° C. or more), convection occurs inside the second tapping pipe 4. That is, when the hot water in the second hot water discharge pipe 4 is cooled by the ambient air and the temperature is lowered, the specific gravity increases, so that it flows downward and moves into the hot water tank 1.

  At this time, the hot water in the hot water tank 1 moves upward in the second hot water discharge pipe 4 so as to be replaced. Due to this convection, the heat loss from the hot water storage tank 1 is increased, so that there is a problem that the efficiency is lowered.

  The present invention solves the above-described conventional problems, and in a configuration using hot water in a hot water storage tank, a hot water storage type hot water supply device excellent in energy saving that can prevent an increase in heat dissipation loss due to convection inside a pipe for taking out hot water. The purpose is to provide.

  In order to solve the above-described conventional problems, a hot water storage type hot water supply apparatus of the present invention is provided in a hot water storage tank, a first hot water pipe connected to an upper portion of the hot water storage tank, the hot water storage tank, and at least a high The second hot water outlet pipe having a water inlet portion for entering hot water in the substantially central portion of the hot water storage tank in the vertical direction, hot water from the first hot water outlet pipe, and hot water from the second hot water outlet pipe are mixed. And a mixing valve.

  Thus, when hot water is used at the heat utilization terminal, the medium-temperature water generated by the hot water returning from the heat exchanger to the hot water storage tank can be effectively used through the second hot water discharge pipe.

  In addition, when hot water is not used at the heat utilization terminal or the hot water outlet, the second hot water outlet pipe is provided inside the hot water storage tank, so that the pipe is not directly cooled by the outside air. Therefore, it is possible to prevent a decrease in operating efficiency due to an increase in heat dissipation loss.

  ADVANTAGE OF THE INVENTION According to this invention, in the structure using the hot water of a hot water tank, the hot water storage type hot water supply apparatus excellent in the energy saving property which can prevent the heat radiation loss increase by the convection inside the piping which takes out middle temperature water can be provided.

The block diagram of the hot water storage type hot water supply apparatus in Embodiment 1 of this invention Control block diagram when the same hot water supply occurs Flow chart of control when hot water is generated The figure which shows the change of the temperature distribution in the same hot water tank Control block diagram when heat is used at the same heat-using terminal Flow chart of control when heat utilization occurs at the same heat utilization terminal (A) The figure showing the temperature distribution before the heat utilization at the same heat utilization terminal (b) The figure showing the temperature distribution immediately after the heat utilization at the same heat utilization terminal (c) At the same heat utilization terminal Figure showing the temperature distribution after hot water is used and hot water is generated The block diagram of the hot water storage type hot water supply apparatus in Embodiment 2 of this invention The block diagram of the hot water storage type hot water supply apparatus in Embodiment 3 of this invention Configuration diagram of other hot water storage type hot water supply devices Configuration diagram of other hot water storage type hot water supply devices Configuration diagram of conventional hot water supply equipment

  A first aspect of the present invention is a hot water storage tank, a first hot water pipe connected to an upper portion of the hot water storage tank, and a hot water at a substantially central portion in the hot water storage tank at least in the height direction. A hot water storage system comprising: a second hot water outlet pipe having a water inlet for receiving water; and a mixing valve for mixing hot water from the first hot water outlet pipe and hot water from the second hot water outlet pipe. It is a water heater.

  Thus, when hot water is used at the heat utilization terminal, the medium-temperature water generated by the hot water returning from the heat exchanger to the hot water storage tank can be effectively used through the second hot water discharge pipe.

  In addition, by providing the second hot water outlet pipe inside the hot water storage tank, the piping is not directly cooled by the outside air, so it is possible to prevent convection in the piping and prevent a decrease in operating efficiency due to an increase in heat dissipation loss. can do.

  The second invention is provided with a plurality of hot water temperature detecting means in the height direction of the hot water storage tank, and the second hot water discharge pipe has substantially the same height as the hot water temperature detecting means in the height direction of the hot water storage tank. In this hot water storage tank, high temperature, medium hot water, and low temperature hot water can be taken out from each of the water intake portions having different heights.

  According to a third aspect of the present invention, an opening / closing means is provided in the water intake section. By adjusting the open / closed state of each opening / closing means, each water intake section having a different height is adjusted inside the hot water tank. Hot, medium and low temperature hot water can be removed as needed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a diagram showing a configuration of a hot water storage type hot water supply apparatus according to Embodiment 1 of the present invention.

  In FIG. 1, a hot water supply apparatus includes a hot water tank 1, a heat pump device that is a heating means 2 for heating water in the hot water tank 1, a first hot water pipe 3 connected to the upper part of the hot water tank 1, The hot water stored in the center of the hot water storage tank 1 in the height direction between the positions where the hot water discharge pipe 3 and the water supply pipe 5 are connected, that is, enters the water from the water inlet portion which is the tip opening of the pipe. And a second hot water discharge pipe 4 connected so that the hot water can be discharged out of the hot water storage tank 1.

  In addition, a water supply branch pipe 10 branched from the water supply pipe 5, a first mixing valve 6 having a first hot water discharge pipe 3 and a second hot water discharge pipe 4 connected to the inlet side, and the first mixing valve 6 is connected to the outlet side of the second mixing valve 7 connected to the outlet side of the hot water pipe 8 and the water supply branch pipe 10 connected to the outlet side, and the mixed water pipe connected to the outlet side of the second mixing valve 7. 9 and.

  And the 2nd tap pipe 4 is installed in the hot water storage tank, and the hot water in the pipe is cooled and convected by the outside air, thereby preventing energy loss.

  In this embodiment, the first mixing valve is disposed immediately after the first hot water outlet pipe and the second hot water outlet pipe come out of the hot water storage tank, and the both pipes are further covered with a heat insulating material, thereby further reducing heat loss due to convection. Can be prevented.

  Further, the hot water supply port 11 connected to the mixed water pipe 9, the hot water temperature detecting means 12 for detecting the hot water temperature at the lower end position of the second hot water outlet pipe 4, and the combined temperature for detecting the hot water temperature flowing through the hot water outlet pipe merging pipe 8. Detection means 13, hot water supply temperature detection means 14 for detecting the temperature of hot water flowing through the mixed water pipe 9, a heat utilization hot water discharge pipe 21 connected to the upper part of the hot water storage tank 1, and a heat exchanger connected to the heat utilization hot water supply pipe 21 20, a heat utilization return pipe 22 connected between the hot water tank 1 upper part, a position where the hot water tank 1 and the second hot water discharge pipe 4 are connected, and a heat utilization terminal 23 connected to the heat exchanger 20. The pump 25 for adjusting the amount of hot water flowing through the heat utilization return pipe 22 and the heat utilization temperature detecting means 24 for detecting the temperature of the hot water flowing through the heat utilization terminal 23 are provided.

  Furthermore, the hot water supply temperature setting means 30 for setting the hot water supply temperature of the hot water supply port 11, the heat use temperature setting means 31 for setting the heat use temperature of the heat use terminal 23, the hot water temperature detection means 12, the combined temperature detection means 13, and the hot water supply The first mixing valve 6 and the second mixing valve 7 are controlled based on the output of the temperature detection means 14 and the setting of the hot water supply temperature setting means 30, and the outputs of the heat use temperature setting means 31 and the heat use temperature detection means 24. And a control device 33 having a control means 32 for controlling the pump 25 based on the setting of the heat utilization temperature setting means 31.

  FIG. 2 shows a block diagram of the control. Based on the settings of the hot water temperature detection means 12, the combined temperature detection means 13, the hot water supply temperature detection means 14, and the hot water supply temperature setting means 30, It comprises control means 32 for controlling the second mixing valve 7.

  The operation and action of the hot water storage type hot water supply apparatus configured as described above will be described below.

  As a basic operation, the hot water tank 1 is filled with a lot of low-temperature water before boiling, and when the operation is started, the water in the hot water tank 1 is sent to the heat pump device 2 where it is heated and heated to hot water. Is returned to the hot water tank 1. As a result, hot water is stored in the hot water tank 1.

  When using the hot water supply after boiling, the hot water in the hot water storage tank 1 discharged through the first hot water discharge pipe 3 and the second hot water discharge pipe 4 is first mixed by the first mixing valve 6 to join the hot water discharge pipe. Pass through tube 8. Then, the hot water from the feed water branch pipe 10 and the second mixing valve 7 are mixed with the hot water supply set temperature and supplied to the hot water supply port 11. Further, water corresponding to the amount of hot water used for hot water supply flows from the lower part of the hot water tank 1 through the water supply pipe 5.

  Here, the operation when using the hot water supply and the operation when using the heat utilization terminal will be described in detail with reference to FIGS.

  The hot water supply temperature is set as the hot water supply set temperature by the hot water supply temperature setting means 30, ts is the hot water supply set temperature of the hot water supply port 11, ts 2 is a temperature higher than the hot water supply set temperature, for example, + 5 ° C., and tm is the hot water temperature detection means 12. The temperature detected in step 1. Further, te is a temperature detected by the heat use temperature detecting means 24, and ts3 is a temperature set by the heat use set temperature means.

  FIG. 3 is a flowchart of control when hot water is generated. When hot water supply is started, the magnitude relationship between tm and ts2 is determined (step 1), and when tm is higher than ts2, the first mixing valve 6 is set so that hot water is discharged only from the second hot water discharge pipe 4. Fully open to the second tapping pipe 4 side (step 2).

When tm is equal to or less than ts, the opening degree of the first mixing valve 6 is adjusted based on the hot water temperature detected by the merging temperature detecting means 13 so that the merging temperature detecting means 13 becomes ts2 (step 3). . Thereafter, the second mixing valve 7 mixes the hot water in the hot water discharge pipe joining pipe 8 and the water in the hot water supply branch pipe 10 so that the output from the hot water supply temperature detection means 14 becomes ts (step 4). Hot water adjusted to the set temperature ts is supplied from the hot water supply port 11 through the mixed water pipe 9.

  FIG. 4 is a diagram showing changes in the temperature distribution in the hot water tank 1. The horizontal axis indicates the temperature, and the vertical axis indicates the height of the hot water tank 1. The temperature distribution of 45 indicates that the upper end of the intermediate temperature layer, which is an intermediate temperature zone, is at the position where the second hot water pipe 4 is connected to the hot water tank 1. In some cases, that is, just before the hot water supply in the middle temperature zone is started. While the hot water is discharged from both the first hot water discharge pipe 3 and the second hot water discharge pipe 4, the intermediate temperature layer moves upward of the hot water storage tank 1 while being reduced.

  When the hot water temperature at the hot water joining pipe 8 when the hot water is discharged from both becomes ts or less, the hot water from the second hot water pipe 4 is stopped, and the intermediate temperature layer is moved as it is above the hot water tank 1. As a result, the size of the intermediate temperature layer is initially 15 f but is reduced to 15 g. 46 is a temperature distribution at the time when the intermediate temperature layer 15g passes through the connection position of the second hot water discharge pipe 4.

  FIG. 5 shows a block diagram of control when heat is used at the heat use terminal 23, and the control of the pump 25 is based on the output of the heat use temperature detecting means 24 and the setting of the heat use temperature setting means 31. It consists of the control means 32 which performs.

  FIG. 6 is a flowchart of control when heat is used at the heat use terminal 23. When the use at the heat utilization terminal is started, the heat utilization temperature detecting means 24 detects the temperature te of the heat utilization terminal, and compares te with the heat utilization terminal set temperature ts3 (step 5). When te is lower than ts3, driving of the pump is started (step 6), and when it is higher, driving of the pump is stopped (step 7).

  FIG. 7 explains the temperature change caused by the hot water from the heat return pipe in the hot water tank 1 and the temperature change when hot water is generated. The horizontal axis indicates the temperature, and the vertical axis indicates the hot water tank 1 height. This shows the temperature distribution. T1 is the feed water temperature, T3 is the temperature of the upper part of the hot water storage tank 1, and T2 is the temperature of the medium temperature water generated by the inflow of hot water from the heat utilization return pipe 22.

  Reference numeral 61 in FIG. 7A denotes an initial temperature distribution. When hot water from the heat utilization return pipe 22 flows into the upper part of the hot water tank 1 from that state, the temperature distribution as indicated by 62 in FIG. It becomes. Although T2 changes with the temperature which flows in from the heat | fever utilization return pipe | tube 22, and T3, the hot water below the position where the heat | fever utilization return pipe | tube 22 of the hot water storage tank 1 is connected is always medium temperature water.

  Thereafter, when hot water is generated, the second hot water discharge pipe 4 is connected to a position below the heat-use return pipe, so that the medium-temperature water generated by the heat-use return pipe 22 is preferentially used, The influence of the temperature distribution change by the utilization return pipe 22 can be removed.

  In addition, since the heat return pipe 22 is connected to the upper part of the hot water tank 1 and the temperature of the lower part of the hot water tank 1 is maintained at the feed water temperature T1, the medium temperature water circulates in the heating device at the time of boiling and the efficiency is increased. There is no decline.

  Further, in the case where hot water is not used at the heat utilization terminal 23 or the hot water supply port 11, the first mixing valve 6 is installed immediately after the second hot water discharge pipe 4, thereby minimizing the piping cooled to the outside air, and Since it can be covered with a heat insulating material, convection in which water whose temperature has decreased in the second hot water discharge pipe 4 flows into the hot water storage tank 1 does not occur, and an increase in heat dissipation loss can be prevented.

  Thus, according to Embodiment 1 of the present invention, by disposing the second hot water discharge pipe 4 in the hot water storage tank 1, heat dissipation loss due to convection between the second hot water discharge pipe 4 and the hot water storage tank 1. Can be prevented.

(Embodiment 2)
FIG. 8 is a diagram showing a configuration of a hot water storage type hot water supply apparatus according to Embodiment 2 of the present invention. The second embodiment of the present invention is different from the first embodiment in that the second hot water discharge pipe 4 shown in FIG. The same number of holes 17 are provided.

  In other words, the same number of holes 17 serving as the water inlet are provided so that hot water stored in the hot water storage tank 1 in the height direction can be discharged from the second hot water discharge pipe 4 in a plurality of high temperature, medium temperature, and low temperature hot water. Is provided. Thereby, in addition to the hot water, it is possible to take out the middle and low temperature hot water from each hole position.

  Further, by changing the size of each hole as necessary, the amount of hot water supplied from each position is controlled, so that hot water can be supplied without using hot water higher than necessary.

(Embodiment 3)
FIG. 9 is a diagram showing a configuration of a hot water storage type hot water supply apparatus according to Embodiment 3 of the present invention. The third embodiment of the present invention differs from the first embodiment in that the incoming water piping is branched at the same position as the hot water temperature detection means of the second hot water discharge pipe 4 shown in FIG. The valve 18 as a means is provided.

  That is, hot water stored in the hot water storage tank 1 in the height direction in a plurality of temperature regions of high temperature, medium temperature, and low temperature is adjusted from the second tapping pipe 4 as necessary by adjusting the opening and closing of each valve. You can take a bath.

  The valve 18 may be operated with a shape memory alloy. By setting the valve 18 to open only in a predetermined temperature range, the hot water at the optimum temperature can be taken out, and the medium temperature can be used without using hot water that is higher than necessary.

  The valve 18 may be an electromagnetic valve. By selecting and opening the valve 18 at which the hot water temperature detected by the hot water temperature detecting means is higher than the required temperature and minimum, the intermediate temperature can be used without using hot water higher than necessary.

  Furthermore, in FIG. 10, the lower end of the 2nd tap pipe 4 shown in FIG. 9 is made into L shape. Thereby, hot water can be taken out from the second hot water discharge pipe 4 in the horizontal direction. Therefore, as shown in the lower end shape of the second tapping pipe 4 in FIG. 9, hot water having a temperature gradient in the vertical direction is used, and the hot water in the hot water storage tank 1 is disturbed and the hot water temperature is detected without expanding the intermediate temperature region. Hot water at the temperature detected by the means 12 can be taken out.

  Moreover, in FIG. 11, the 2nd tap pipe 4 is provided in the outer wall vicinity in the hot water storage tank. As a result, the distance between the tip of the second hot water discharge pipe and the opposite side wall surface of the hot water tank is increased, and the intermediate temperature can be taken out while suppressing the hot water disturbance in the hot water tank.

  As described above, in the present invention, the heat utilization return pipe 22 is generated by the configuration in which the connection position of the heat return pipe 22 with the hot water storage tank 1 is higher than the connection position of the second hot water discharge pipe 4 with the hot water storage tank 1. Since the effect of medium temperature water can be removed and efficiency reduction during boiling can be prevented, good usability and high energy savings can be realized.

As described above, the hot water storage type hot water supply apparatus according to the present invention reduces the decrease in efficiency due to the use of the heat utilization terminal when using the heat of the hot water in the hot water storage tank. In addition to being applicable, it can also be applied to large-scale applications such as business use in a system having a heat source and a hot water tank, and can provide excellent energy saving.

1 Hot water tank 2 Heating means (heat pump device)
DESCRIPTION OF SYMBOLS 3 1st hot water pipe 4 2nd hot water pipe 5 Water supply pipe 6 1st mixing valve 7 2nd mixing valve 8 Hot water discharge pipe merge pipe 9 Mixed water pipe 10 Feed water branch pipe 11 Hot water outlet 12 Hot water temperature detection means 13 Combined temperature Detection means 14 Hot-water supply temperature detection means 16 Boiling pipe 17 Hole (water entry part)
18 Valve (opening / closing means)
DESCRIPTION OF SYMBOLS 20 Heat exchanger 21 Heat utilization hot water pipe 22 Heat utilization return pipe 23 Heat utilization terminal 24 Heat utilization temperature detection means 25 Pump 30 Hot water supply temperature setting means 31 Heat utilization temperature setting means 32 Control means 33 Control apparatus

Claims (3)

A hot water storage tank, a first hot water pipe connected to an upper portion of the hot water storage tank, and a water inlet portion that is disposed inside the hot water storage tank and that enters hot water at a substantially central portion in the hot water storage tank at least in a height direction. A hot water storage type hot water supply apparatus comprising: a second hot water outlet pipe having a mixing valve that mixes hot water from the first hot water pipe and hot water from the second hot water pipe. A plurality of hot water temperature detecting means are provided in the height direction of the hot water tank, and a water inlet portion is provided at a position substantially the same as the hot water temperature detecting means in the second hot water discharge pipe in the height direction of the hot water tank. The hot water storage type hot water supply apparatus according to claim 1, wherein: The hot water storage type hot water supply apparatus according to claim 2, wherein an opening / closing means is provided in the water inlet.

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