JP6656983B2 - Water heater - Google Patents

Description

  The present invention relates to a hot water supply apparatus for supplying water to a closed tank, heating the water in the closed tank with a heat source device to generate hot water, and supplying the hot water in the closed tank to an open tank.

  Water is supplied to the closed tank, the water in the closed tank is heated by a heat source device to generate hot water, and the hot water in the closed tank is opened through a plurality of flow control valves connected in parallel to each other. There is known a hot water supply device for supplying water. The plurality of flow control valves adjust the flow rate of warm water from the closed tank to the open tank by changing the opening degree.

JP 2009-270734 A

  In the above hot water supply device, the opening degrees of the plurality of flow control valves are uniformly controlled so that the flow rate of the hot water from the closed tank to the open tank becomes a desired predetermined amount. For example, when reducing the flow rate of the hot water, the opening degrees of the plurality of flow control valves are both reduced by the same value. When increasing the flow rate of the hot water, the openings of the plurality of flow control valves are both increased by the same value.

  However, when the opening degree of the flow control valve is small, the flow rate of water passing through the inside of the flow control valve locally increases, and the metal portion in the valve is easily eroded by the increased flow of water. On the side where the opening of the flow control valve is large, the rate of change of the flow with respect to the change of the opening is small, so that it may not be possible to adjust the flow accurately.

  An object of an embodiment of the present invention is to provide a highly reliable hot water supply apparatus capable of preventing erosion inside a flow control valve and accurately adjusting a flow rate of hot water from a closed tank to an open tank. .

The hot water supply device according to claim 1 supplies water to the closed type tank, heats the water in the closed type tank with a heat source device to generate hot water, and connects the hot water in the closed type tank to a plurality of flow rates connected in parallel with each other. A temperature detecting means for detecting a temperature of water in the closed type tank through an adjusting valve, and a temperature detecting means for detecting a temperature of the water in the closed type tank; Control means for controlling the degree of opening of the flow control valve . The plurality of flow control valves are at least first and second flow control valves. The control means obtains a target total opening Qt of the first and second flow control valves for maintaining the temperature detected by the temperature detecting means at a set value; When the value falls within the upper limit value of the opening range suitable for use of the valve, the value of the target total opening Qt is assigned to the opening Q1 of the first flow control valve; If the upper limit value of the opening area suitable for use of the flow control valve is exceeded, the value of the target total opening Qt is changed to the use of the opening area suitable for use of each of the first and second flow control valves. The first and second flow control valves are assigned to the opening degrees Q1 and Q2 so that the rate becomes as high as possible.

FIG. 1 is a diagram showing a configuration of an embodiment. The figure which shows the optimal opening degree area | region of each flow control valve in one Embodiment. 5 is a flowchart illustrating control according to an embodiment. The figure which shows the opening degree allocation condition of one Embodiment. The figure which shows the distribution of the opening degree of each flow control valve in one embodiment in the form of a bar graph for easy understanding.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 1, water from a water supply source flows to a plurality of heat source devices 1 via a water supply side pipe 2. The water flowing to these heat source devices 1 is heated by pumping heat of the heat pump refrigeration cycle to become hot water. This hot water flows to the hot water supply side pipe 3.

  Each heat source unit 1 includes a compressor 11, a four-way valve 12, a water heat exchanger 13, an expansion valve (decompressor) 14, an outdoor heat exchanger (air heat exchanger) 15, an outdoor fan 16, a pump 17, and a controller. 10 inclusive. A heat pump refrigeration cycle is configured by pipe connection of the compressor 11, the four-way valve 12, the water heat exchanger 13, the expansion valve 14, and the outdoor heat exchanger 15. The refrigerant discharged from the compressor 11 flows through the four-way valve 12 into the refrigerant flow path of the water heat exchanger 13, and the refrigerant passing through the refrigerant flow path passes through the expansion valve 14, the outdoor heat exchanger 15, and the four-way valve 12. Then, it is sucked into the compressor 11. The water heat exchanger 13 functions as a condenser, and the outdoor heat exchanger 15 functions as an evaporator. The water in the water supply side pipe 2 is sent to the water flow path of the water heat exchanger 13 by the pump 17. The water sent to the water flow path is heated by the refrigerant passing through the refrigerant flow path of the water heat exchanger 13 to become hot water. This hot water flows to the hot water supply side pipe 3. The controller 10 controls the compressor 11, the four-way valve 12, the outdoor fan 16, the pump 17, and the like in the heat source device 1.

  A sealed tank unit 4 is connected between the water supply pipe 2 and the hot water supply pipe 3. The closed tank unit 4 includes a closed tank 21, temperature sensors (temperature detecting means) 21a to 21e, a plurality of flow control valves (first, second, and third flow control valves) 31, 32, and 33, and a controller. 20. The closed type tank 21 has an opening at the bottom which serves as an inlet for water supplied from a water supply source (water supply side pipe 2) and an outlet for water to each heat source device 1 (water supply side pipe 2). The upper part has an opening that serves as an inlet for the hot water supplied from the heat source unit 1 (the hot water supply pipe 3) and an outlet for the hot water to the open tank 5 (the hot water supply pipe 3).

  The water in the closed tank 21 flows through the lower opening to the water supply pipe 2, and the water in the water supply pipe 2 is sent to each heat source device 1 and heated. The warm water flowing from each heat source unit 1 to the hot water supply side pipe 3 flows into the closed tank 21 through the upper opening of the closed tank 21 and is temporarily stored in the closed tank 21. The warm water W stored in the closed tank 21 flows to the hot water supply pipe 3 through the upper opening. The hot water W flowing into the hot water supply pipe 3 flows into the lower part of the open tank 5 through the flow control valves 31, 32, 33.

  The open tank 5 stores the hot water W supplied from the hot water supply pipe 3, and supplies the stored hot water W to a hot water supply load via a hot water pipe (not shown). The interior of the open type tank 5 is divided into a hot water area in which the hot water W supplied from the hot water supply pipe 3 is stored, and an air layer A generated above the hot water area. A pressure sensor 5 a for detecting the pressure of water in the open tank 5 is attached to a lower portion of the open tank 5.

  The flow control valves 31, 32, and 33 adjust the flow rate of hot water by changing the opening degree, and are arranged in parallel with each other on the hot water supply side pipe 3 between the closed tank 21 and the open tank 5. ing.

  The flow control valves 31, 32, and 33 have, as an opening degree region suitable for use, an optimal opening degree region not less than the lower limit value Qa and not more than the upper limit value Qb indicated by a two-dot chain line in FIG. The lower limit value Qa corresponds to, for example, an opening of 20% when the full opening is set to 100%. The upper limit value Qb corresponds to, for example, an opening of 80% when the full opening is set to 100%. Q indicates the opening degree of each of the flow control valves 31, 32, 33, L indicates the flow rate of the hot water passing through the flow control valves 31, 32, 33, and Lx indicates the local flow rate in the flow control valves 31, 32, 33. . The flow control valves 31, 32, and 33 are the same product having the same characteristics, and have the same optimal opening degree region.

  In the minimum opening region (also referred to as a small opening region) smaller than the lower limit value Qa, the flow rate L of the water passing through the flow regulating valves 31, 32, and 33 locally increases, and the flow rate L increases. The metal part in the valve is easily eroded. In the minimum opening region exceeding the upper limit value Qb (also referred to as a large opening region), the rate of change of the flow rate L with respect to the change of the opening degree Q may be small, and the flow rate L may not be able to be accurately adjusted. In response to these inconveniences, the minimum opening region less than the lower limit value Qa and the maximum opening region exceeding the upper limit value Qb are determined as opening regions not suitable for use of the flow control valves 31, 32, and 33, and the remaining lower limit values are set. A region equal to or larger than Qa and equal to or smaller than the upper limit value Qb is defined as an optimal opening degree region.

  The temperature sensors 21 a to 21 e are sequentially arranged along the depth direction of the closed tank 21, and each detect the temperature of water in the closed tank 21. The temperature of the water in the closed tank 21 is lower at the lower part and higher at the upper part. The temperature sensor 21a detects the temperature of the lowermost water, and the temperature sensor 21e detects the temperature of the uppermost water.

  The controller 20 controls the operation of each heat source unit 1 via each controller 10 connected to the signal line, and controls the opening of the flow control valves 31, 32, 33 in the closed tank unit 4. The main functions include first to n-th control means 20a to 20n.

  The first control means 20a controls the opening degrees Q1, Q2, Q3 of the flow regulating valves 31, 32, 33 so that the flow rate of the hot water from the closed tank 21 to the open tank 5 becomes a predetermined amount. Specifically, the first control means 20a operates so that the detection temperature of the second temperature sensor 21d from the top in the sealed tank 21 maintains the set value, that is, the amount of hot water obtained by each heat source unit 1 The openings Q1, Q2, and Q3 of the flow control valves 31, 32, and 33 are controlled so that the amount of hot water flowing from the mold tank 21 to the open mold tank 5 is the same.

  The second control means 20b detects the amount (or water level) of the hot water in the open tank 5 from the detection pressure of the pressure sensor 5a, and when the detected amount reaches almost full, the control of the first control means 20a is performed. , The operation number of each heat source unit 1 is reduced or the operation of each heat source unit 1 is forcibly stopped.

  Next, the control executed by the controller 20 will be described with reference to the flowchart of FIG.

  The controller 20 calculates the target total opening Qt of the flow regulating valves 31, 32, 33 for maintaining the temperature detected by the temperature sensor 21d at the set value (step S1), and calculates the value of the calculated target total opening Qt. Are assigned to the openings Q1, Q2, Q3 of the flow regulating valves 31, 32, 33 according to the opening assignment conditions of FIG. Hereinafter, this assignment will be described.

  The opening assignment condition in FIG. 4 associates the value of the target total opening Qt that differs by "10%" with the values of the openings Q1, Q2, and Q3 to be assigned according to the respective target total opening Qt. It is stored in the internal memory of the controller 20 in advance. The distribution of the opening degrees Q1, Q2, Q3 is shown in FIG. 5 in the form of a bar graph for easy understanding.

  When target total opening Qt is equal to or smaller than upper limit value Qb (80%) (0 ≦ Qt ≦ Qb; YES in step S2), controller 20 sets value of target total opening Qt to “0 to 80%”. Is assigned to the opening Q1 of the flow control valve 31, and 0% is assigned to the openings Q2 and Q3 of the flow control valves 32 and 33 (step S3). In this case, the priority order of the allocation to the flow control valves 31, 32, and 33 is the flow control valve 31 in the first place, the flow control valve 32 in the second place, and the flow control valve 33 in the third place. Regarding the priority order of the allocation to the flow control valves 31, 32, 33, each time the target total opening Qt is calculated in step S1, the rotation is performed sequentially one by one. Hereinafter, description of this rotation will be omitted.

  If the target total opening degree Qt is larger than the upper limit value Qb (Qb <Qt; NO in step S2) and smaller than twice the upper limit value Qb, ie, “160%” (Qt <2Qb; YES in step S4, step S5) YES), the controller 20 sets the value of the target total opening Qt “90% to 150%” to a value that minimizes the usage rate of the opening area (optimum opening area) suitable for the use of each of the flow control valves 31 and 32. It is assigned to the opening degrees Q1 and Q2 of the flow control valves 31 and 32 so as to be higher (step S6). Specifically, the value of “Qb−Qa / 2” is assigned to the opening Q1 of the flow control valve 31, and the remaining value “Qt−Q1” obtained by subtracting the value of the opening Q1 from the target total opening Qt is obtained. It is assigned to the opening Q2 of the flow control valve 32. Zero percent is assigned to the opening Q3 of the flow control valve 33.

  If the target total opening Qt is 90%, 80% is allocated to the opening Q1 of the flow control valve 31 and the remaining 10% is allocated to the opening Q2 of the flow control valve 32. Although the opening Q1 of 31 can be kept within the optimum opening range, the opening Q2 of the flow regulating valve 32 falls below the lower limit Qa (20%) of the optimum opening range. In contrast, in the process of step S6, when the target total opening Qt is 90%, 70% is allocated to the opening Q1 of the flow control valve 31 and 20% is allocated to the opening Q2 of the flow control valve 32. become. The opening degrees Q1 and Q2 of the flow control valves 31 and 32 are both in the optimal opening range. After this assignment, the controller 20 returns to step S1 and repeats the calculation of the target total opening Qt.

  If the target total opening Qt is equal to twice the upper limit value Qb, ie, “160%” (Qt = 2Qb; NO in step S2, YES in step S4, NO in step S5), the controller 20 sets the target The value of the total opening Qt “160%” is set so that the usage rate of the opening area (optimum opening area) suitable for the use of each of the flow adjustment valves 31 and 32 is maximized as much as possible. Assigned to degrees Q1 and Q2 (step S7). Specifically, the upper limit Qb (80%) is assigned to the opening Q1 of the flow regulating valve 31, the upper limit Qb is similarly assigned to the opening Q2 of the flow regulating valve 32, and the opening Q3 of the flow regulating valve 33 is assigned to Assign zero. Then, the controller 20 returns to step S1, and repeats the calculation of the target total opening Qt.

  When the target total opening Qt is smaller than the value “240%” that is three times the upper limit value Qb (Qt <3Qb; NO in step S2, NO in step S4, YES in step S8, YES in step S9), the controller 20 Sets the value of the target total opening Qt “170% to 230%” so that the usage rate of the opening area (optimal opening area) suitable for the use of each of the flow control valves 31, 32, and 33 is maximized. It is assigned to the opening degrees Q1, Q2, Q3 of the flow control valves 31, 32, 33 (step S10). Specifically, the upper limit Qb is assigned to the opening Q1 of the flow control valve 31, the value “Qb−Qa / 2” is assigned to the opening Q2 of the flow control valve 32, and the remaining value “Qt− (Q1 + Q2)” Is assigned to the opening degree Q3 of the flow control valve 33. Then, the controller 20 returns to step S1, and calculates the target total opening Qt.

  When the target total opening Qt is equal to the value “240%” that is three times the upper limit value Qb (Qt = 3Qb; YES in step S8, NO in step S9), the controller 20 sets the target total opening Qt to The value "240%" is set so that the usage rate of the opening area (optimal opening area) suitable for use of each of the flow control valves 31, 32, and 33 is maximized as much as possible. Assigned to Q1, Q2, Q3 (step S11). Specifically, the upper limit Qb is assigned to the opening Q1 of the flow regulating valve 31, the upper limit Qb is similarly assigned to the opening Q2 of the flow regulating valve 32, and the remaining value “Qt− (Q1 + Q2)” is assigned to the flow regulating valve. 33 is assigned to the opening degree Q3. Then, the controller 20 returns to step S1, and repeats the calculation of the target total opening Qt.

  When the target total opening Qt is larger than the value “240%” three times the upper limit value Qb and equal to or less than the value “3Qb + Qa” (3Qb <Qt ≦ “3Qb + Qa”; NO in step S2, NO in step S4, and step S8) NO, YES in step S12), the controller 20 sets the value of the target total opening Qt (250% or 260%) to an opening region (optimum opening) suitable for use of each of the flow control valves 31, 32, and 33. The flow rates of the flow control valves 31, 32, and 33 are assigned to the opening degrees Q1, Q2, and Q3 so that the usage rate of the (area) becomes as high as possible (step S13). Specifically, the value of “Qt−2Qb” is assigned to the opening Q1 of the flow regulating valve 31, the upper limit Qb is assigned to the opening Q2 of the flow regulating valve 32, and the upper limit Qb is similarly assigned to the opening of the flow regulating valve 33. Assign to degree Q3. Then, the controller 20 returns to step S1, and repeats the calculation of the target total opening Qt.

  When the target total opening Qt is greater than the value “3Qb + Qa” and equal to or less than the value “3Qb + 2Qa” (“3Qb + Qa” <Qt ≦ “3Qb + Qa”; NO in step S2, NO in step S4, NO in step S8, and NO in step S12) The controller 20 sets the value of the target total opening Qt (270% or 280%) to an opening region (optimum opening region) suitable for use of each of the flow control valves 31, 32, 33 (step S14: YES). ) Are assigned to the opening degrees Q1, Q2, Q3 of the flow rate regulating valves 31, 32, 33 so that the usage rate becomes as high as possible (step S15). Specifically, 100% is assigned to the opening Q1 of the flow regulating valve 31, the value of "Qt- (100 + Qb)" is assigned to the opening Q2 of the flow regulating valve 32, and the upper limit Qb is set to the opening of the flow regulating valve 33. Assign to degree Q3. Then, the controller 20 returns to step S1, and repeats the calculation of the target total opening Qt.

  When the target total opening Qt is larger than “3Qb + 2Qa” and equal to or less than 300% (3Qb + 2Qa <Qt ≦ 300; NO in step S2, NO in step S4, NO in step S8, NO in step S12, NO in step S14), The controller 20 sets the value (290% or 300%) of the target total opening Qt to be as high as possible in the opening regions (optimal opening regions) suitable for the use of the flow control valves 31, 32, and 33, respectively. It is assigned to the opening degrees Q1, Q2, and Q3 of the flow control valves 31, 32, and 33 so as to be as follows (step S16). Specifically, 100% is allocated to the opening Q1 of the flow control valve 31, 100% is allocated to the opening Q2 of the flow control valve 32, and the remaining value “Qt−200%” is used to open the flow control valve 33. Assign to degree Q3. Then, the controller 20 returns to step S1, and repeats the calculation of the target total opening Qt.

  As described above, the value of the target total opening Qt is set to the opening degree Q1, Q2 of the flow regulating valve 31, 32, 33 so that the usage rate of the optimal opening area of the flow regulating valve 31, 32, 33 increases as much as possible. By allocating to Q3, the usage rate of the small opening area where the inside of the flow control valves 31, 32, and 33 tends to erode decreases, and the usage rate of the large opening area where the rate of change in the flow rate is small decreases. Therefore, erosion inside the flow control valves 31, 32, and 33 can be prevented, and the flow rate of hot water from the closed tank 21 to the open tank 5 can be accurately adjusted, so that the reliability as a hot water supply device can be improved. Is greatly improved.

  Since the priority order of allocation to the flow control valves 31, 32, 33 is rotated one by one among the flow control valves 31, 32, 33, the use frequency of the flow control valves 31, 32, 33 can be made uniform, The life of the flow control valves 31, 32, 33 is extended.

  In the above embodiment, three flow control valves are used. However, the number of flow control valves can be similarly set to two or four or more.

  Although the case where the lower limit value Qa of the optimum opening degree region is 20% and the upper limit value Qb is 80% has been described as an example, the numerical value is not limited, and may be appropriately determined according to the characteristics of the flow control valve.

  The case where the usage rate of the flow control valves 31, 32, and 33 in the optimum opening area is increased has been described as an example, but the usage rate of the flow control valves 31, 32, and 33 in the minimum opening area (less than the lower limit value Qa) is lowered. Or the usage rate of the flow control valves 31, 32, 33 in the maximum opening area (above the lower limit Qb) may be reduced, or the usage rate of the minimum opening area and the usage of the maximum opening area may be reduced. Both rates may be low.

  In addition, the above embodiments and modified examples are presented as examples, and are not intended to limit the scope of the invention. The new embodiments and modified examples can be implemented in other various forms, and various omissions, rewrites, and changes can be made without departing from the spirit of the invention. In these embodiments and modifications, the scope of the invention is included in the gist, and is included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 1 ... Heat source machine, 2 ... Water supply side piping, 3 ... Hot water supply side piping, 4 ... Closed tank unit, 5 ... Open tank, 5a ... Water level sensor, 10, 20 ... Controller, 11 ... Compressor, 13 ... Water Heat exchanger, 14: expansion valve (decompressor), 15: outdoor heat exchanger, 17: pump, 21: sealed tank, 21a to 21e: temperature sensor (temperature detecting means), 31, 32, 33: flow rate adjustment valve

Claims (3)

Water is supplied to the closed tank, the water in the closed tank is heated by a heat source device to generate hot water, and the hot water in the closed tank is opened through a plurality of flow control valves connected in parallel to each other. Hot water supply device for supplying to
Temperature detection means for detecting the temperature of water in the closed type tank,
Control means for controlling the opening degree of each of the flow control valves so that the temperature detected by the temperature detection means maintains a set value;
With
The plurality of flow control valves are at least first and second flow control valves,
The control means includes:
Calculating a target total opening degree Qt of the first and second flow regulating valves for maintaining the temperature detected by the temperature detecting means at a set value;
When the target total opening Qt is within the upper limit of an opening range suitable for use of the first flow control valve, the value of the target total opening Qt is set to the opening Q1 of the first flow control valve. allocation,
When the target total opening Qt exceeds an upper limit value of an opening range suitable for use of the first flow control valve, the value of the target total opening Qt is set to each of the first and second flow control valves. Are assigned to the opening degrees Q1 and Q2 of the first and second flow control valves so that the usage rate of the opening area suitable for the use of the first and second flow control valves is as high as possible.
A hot water supply device characterized by the above-mentioned. The closed type tank has an inflow port of water supplied from a water supply source and an outflow port of water to the heat source unit at a lower portion, and an inflow port of hot water supplied from the heat source unit and the open type tank. Having a hot water outlet at the top,
The temperature detecting means detects a temperature of water above the closed type tank,
The hot water supply device according to claim 1 , wherein: The control means rotates a priority order of assigning the target total opening Qt to the first and second flow control valves between the first and second flow control valves.
The hot water supply device according to claim 1 , wherein:

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