JPS61246553A - Solar-heat utilizing heat collector - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a heat collecting device using a heat pump as a means for collecting solar heat.

2. Description of the Related Art As shown in FIG. 3, a conventional solar heat collection device of this type includes a refrigerant circuit in which a compressor 1, a condenser 3, an expansion device 4, and a heat collector 5 are successively connected, a hot water storage WI 7, water circulation pump 8,
The hot water supply circuit is composed of a water heater 9 connected to the condenser 3 and a water heater 9 having a heat exchange relationship.The heat collector 5 absorbs solar heat and atmospheric heat, and the absorbed heat is converted into the compressor 1. The added heat is exchanged between the condenser 3 and the water heater 9 to raise the temperature of the water in the hot water tank 7.

Problems to be Solved by the Invention However, in the above configuration, since the heat collector 5 absorbs solar heat and atmospheric heat, the amount of heat collected per unit time increases in the summer when the hot water supply load is low, and in the winter when the hot water supply load is high. The amount of heat collected per unit time is small. Therefore, the hot water supply load and the heat collection amount have contradictory characteristics, and especially in winter, the heat collection amount cannot satisfy the hot water supply load, resulting in an insufficient amount of heat collection. In order to solve this drawback, if the size and specifications of the equipment are designed based on winter standards, the equipment will become larger, and in the summer, the equipment will become too large, causing problems in terms of cost and ease of construction. Also, as a matter of course, in the summer, the operating time becomes even shorter, and the amount of heat utilized by solar heat is small, resulting in a problem that the operating efficiency of the system is poor.

The present invention solves these conventional problems, and aims to increase the amount of heat collected in winter and improve the operating efficiency of the system.

Means for Solving the Problems In order to solve the above problems, the solar heat collecting device of the present invention includes a frequency conversion compressor, a four-way valve, a condenser, an expansion device, a heat collector, and A refrigerant circuit consisting of a bypass circuit with a check valve at the top, a hot water supply circuit connected to a hot water storage tank, a 7-liter variable flow water circulation pump, a water heater having a heat exchange relationship with the condenser, and a refrigerant at the inlet of the collector. a temperature detector that detects temperature; a plurality of temperature setting devices with different temperature setting values; and a temperature detector that detects the refrigerant temperature at the inlet of the heat collector to determine the frequency of the frequency conversion compressor and the flow rate of the variable flow rate water circulation pump. the frequency of the frequency converting compressor and the variable flow rate water circulation when the refrigerant temperature at the inlet of the heat collector is lower than the temperature setting value of the arbitrary hot water temperature setting device of the temperature setting device. The flow rate of the pump is increased, and when the temperature is higher than a set value, the frequency of the frequency conversion compressor and the flow rate of the variable flow rate water circulation pump are decreased.

Operation The present invention aims to increase the amount of heat collected during the winter when the hot water supply load is large, and to improve the operating efficiency of the system during the summer when the hot water supply load is low, by using the above-described configuration.

Example Embodiments of the present invention will be described below with reference to the accompanying drawings.

In FIGS. 1, 2, and 3, there is a single frequency conversion type compressor, a 2//i four-way valve, and a 3r/'i condenser, which perform the function of condensing the refrigerant. 4-piece expansion device, 5-piece heat collector,
It collects solar heat and atmospheric heat and evaporates the refrigerant. 6
This check valve is provided in a bypass circuit parallel to the expansion device 4.

In addition, the frequency conversion type compressor 1, the four-way valve 2, the
3, an expansion device 4, a check valve 6 provided in parallel with the expansion device 4, a heat collector 5, the four-way valve 2, and the frequency conversion compressor are connected in sequence to form a refrigerant sealed circuit. do. Reference numeral 7 denotes a hot water storage tank, an 8-channel water circulation pump, and a 9-channel water heater, which have a heat exchange relationship with the condenser 3 and raise the temperature of the water. In addition, the hot water storage tank 7, the modified water circulation pump 8, and the nine water heaters are successively connected to form a hot water supply circuit.

A temperature detector 10 detects the temperature of the refrigerant at the inlet of the heat collector 5. 11 is the temperature setting value Tla1T'+b%Ti
e “””, T2, T3 (T3<T2<Tla<T+b
12 is a control unit that compares the signal of the temperature detector 10 and the signal of the temperature setter 11 to change the refrigerant flow direction of the four-way valve 2. The frequency of the frequency converting compressor 1 and the flow rate of the variable flow rate water circulation pump 8 are controlled.

In the above configuration, the high temperature and high pressure refrigerant gas compressed by the frequency converting compressor 1 flows into the condenser 3 through the west valve 2 in the direction of the solid arrow in FIG. 1, where it is condensed and liquefied to the supercooled liquid. It flows into the expansion device 4, where it is reduced in pressure to a pressure having a saturation temperature lower than the outside air temperature, and flows into the heat collector 5. Then, solar heat and atmospheric heat are collected, evaporated and gasified, and returned to the compressor 1 via the four-way valve. On the other hand, water sent from a water heater 9-type water circulation pump 8 having a heat exchange relationship with the condenser 3 is heated by condensation heat and returned to the hot water storage tank 7. In this cycle, due to the decrease in enthalpy of the outside air as the outside temperature decreases, the amount of atmospheric heat absorbed by the heat collector 5 decreases, and the refrigerant temperature at the inlet of the heat collector 5 decreases. Therefore, the temperature is detected by the temperature detector 10, and the set values Tla, Tlb, Tlc, etc. of the temperature setting device 11 are detected.
- When the frequency of the compressor 1 becomes lower, the control unit 12 sends a signal to gradually increase the frequency of the compressor 1 in order to increase the capacity. At this time, since the condensing capacity increases, the high pressure in the condenser 3 increases, which deteriorates the operating efficiency of the system. However, in the present invention, since the flow rate of the variable flow rate type water circulation pump 8 is simultaneously increased from the control unit 12, there is no increase in high pressure and the operating efficiency of the system is also good. Therefore, even if the outside temperature decreases, the insufficient amount of heat collection can be alleviated, and the operating efficiency of the system can also be improved. If the outside temperature further decreases and the operation continues when the surface temperature of the heat collector 5 is below the dew point temperature of the outside air and below the freezing point, frost will form on the surface of the heat collector 50 and the amount of heat collected will decrease. ,
System operation efficiency is also poor. In this case, as a matter of course, the inlet refrigerant temperature of the heat collector 5 is low, so the present invention detects the inlet refrigerant temperature of the heat collector 5 with the temperature detector 10, When the temperature setting value T3 is reached,
A signal is sent from the control unit 12 to the four-way valve 2 to change the refrigerant flow direction to the direction shown by the broken line in FIG. . This defrosting cycle will be described below. The gas refrigerant discharged from the frequency conversion compressor 1 flows into the heat collector 5 as shown by the broken line in FIG. 1 via the four-way valve 2, where it melts frost and becomes liquid phase refrigerant. It flows through the check valve 6 and flows into the condenser 1-3 vessel 3. Here, the liquid phase refrigerant is heated by the water sent from the variable flow rate water circulation pump 8 via the water heater 9, evaporates into gas, and returns to the frequency conversion type compressor 1 via the four-way valve 2. . In this cycle, while the frost in the heat collector 5 is melting, the temperature of the refrigerant at the temperature detector 10 is below 0°C, but once the frost has finished melting, the temperature of the gas refrigerant increases because no heat is taken away by the frost. . Therefore, the refrigerant temperature is detected by the temperature detector 10, and compared with the temperature setting device 11 having the refrigerant temperature set value T2 at which frost melting ends, and a signal is sent from the control section to the four-way valve 2 to adjust the refrigerant flow direction. Switch to heat collection operation in the direction of the solid line in Figure 1. Therefore, heat collection operation is possible even when the outside temperature drops, and the amount of heat collection can be greatly increased. Also, during the cycle during frost thawing, the frequency of the frequency converting compressor 1 and the flow rate of the variable flow rate water circulation pump are increased to shorten the frost thawing time and reduce the flow of liquid to the frequency converting compressor 1. It eliminates backlogs and ensures system operating efficiency and equipment reliability.

Effects of the Invention As described above, the solar heat collection device of the present invention provides the following effects.

(1) Detecting the refrigerant temperature at the inlet of the collector, and controlling the frequency of the frequency converter compressor and the flow rate of the variable flow rate water circulation pump, and as the refrigerant temperature at the collector inlet becomes lower, the frequency converter compressor Since the frequency of the water circulation pump and the flow rate of the variable flow rate water circulation pump are increased, the amount of heat collected can be increased in the winter when the hot water supply load is large, and the amount of heat collected can be increased in the event that frost forms on the surface of the collector and the amount of heat collected is reduced. Even during frost, the defrosting operation can be shortened and the heat collection operation can be expanded to increase the amount of heat collection. On the other hand, in the summer when the hot water supply load is small, the frequency of the frequency conversion compressor and the flow rate of the variable flow rate water circulation pump can be reduced to improve the operating efficiency of the system.

[Brief explanation of drawings]

Figure 1 shows a solar heat collecting device according to an embodiment of the present invention...
...Two-layer wave number conversion type compressor, 2...Four-way valve, 3
...Condenser, 4...Expansion device, 5...
... Heat collector, 6 ... Check valve, 7 ...
・Hot water tank, 8... Variable flow rate water circulation pump, 9
...Water heater, 10...Temperature detector,
11...Temperature setting device, 12...Control unit. Name of agent: Patent attorney Toshio Nakao and 1 other person
2 Figure 3

Claims (2)

[Claims] (1) A refrigerant circuit consisting of a frequency conversion compressor, a four-way valve, a condenser, an expansion device, a heat collector that collects solar heat and atmospheric heat, a bypass circuit with a check valve in parallel with the expansion device, and hot water storage. a hot water supply circuit that connects a tank, a variable flow rate water circulation pump, a water heater having a heat exchange relationship with the condenser, a temperature detector that detects the refrigerant temperature at the inlet of the collector, and a plurality of temperature detectors having different temperature settings. A solar heat collecting device comprising a temperature setting device and a control unit that detects the refrigerant temperature at the inlet of the heat collector and controls the frequency of the frequency converting compressor and the flow rate of the variable flow rate water circulation pump. (2) When the refrigerant temperature at the inlet of the collector is lower than the temperature setting value of the arbitrary temperature setting device of the temperature setting device, the frequency of the compressor and the flow rate of the variable flow rate water circulation pump are increased; 2. The solar heat collecting device according to claim 1, wherein the frequency of the compressor and the flow rate of the variable flow rate water circulation pump are reduced when the temperature is higher than the temperature setting value of the arbitrary temperature setting device.