JPS6138358A - Solar heat collector - Google Patents

Abstract

PURPOSE:To make electric power consumption zero in case sunshine is strong while permit to obtain reservation of hot-water in case there is no sunshine by a method wherein the evaporator of heat pump circuit is arranged in the returning pipe of a heat collecting circuit and the condenser of the heat pump circuit is arranged in the returning pipe of the heat collecting circuit. CONSTITUTION:In the case of condition that solar heat can be collected with a high efficiency, the operation of compressor 10 of the heat pump circuit 25 is stopped, then, only liquid enters into a heat exchanger 2 through the sending pipe 5 and dissipates the heat thereof. The operating liquid, cooled by the heat exchanger 2, flows into the lower chamber 15 of a control tank 12 through the returning pipe 6, pushed a float 17 up and the operating liquid in the lower chamber 15 is returned to a heat collector through the returning pipe 19. On the other hand, when the level of operating liquid in the lower chamber 15 is lowered and pushes down the float 17 to close the connecting port 16 of the valve 18, the operating liquid is sent by pressure into the heat exchanger 2 from the heat collector 3 again and heat transfer is effected. In case the sunshine is weak, the operating liquid, flowing through the returning pipe 6 of the heat collecting circuit 13, is cooled by the evaporator 24 while the heat, obtained by the evaporator 24, is dissipated into the operating liquid, flowing through the sending pipe 5, in the condenser 7, therefore, the temperature in the hot-water reserving tank 1 may be increased through the heat exchanger 2.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is applied to solar water heaters or solar heating systems using a heat pump as an auxiliary heat source to improve heat collection performance and economic efficiency. Regarding a heat collection device.

Configuration of the conventional example and its problems The conventional solar heat collector has a hot water storage tank 1 as shown in Fig. 2.
A heat exchanger 2 and a heat collector 3 installed inside are connected in a closed circuit by an outgoing pipe 5 and a returning pipe 6 via a pump 4, and a working fluid is sealed inside the pipe. A heat collection circuit was constructed. In this configuration, if there is strong solar radiation, pump 4
is operated, the working fluid is circulated, the working fluid is heated in the heat collector 3, the heat is radiated by the heat exchanger 2, and the heat is stored in the hot water storage tank 1. The temperature of
There is a problem in that the temperature of the working fluid entering the heat collector a also increases, and the heat collection performance decreases. Furthermore, there is also the problem that heat cannot be collected when sunlight is weak, and the temperature within the hot water tank 1 does not rise on cloudy or rainy days.

On the other hand, in order to solve the above problem, by making the temperature of the working fluid flowing into the heat collector lower than the temperature of the surrounding air, it is possible to collect atmospheric heat more than from the air even in the absence of solar radiation. In addition, heat pump circuits are often applied to heat collecting devices. As shown in Figure 3, this type of conventional solar heat collector has a heat pump circuit +i
The heat collector 3, which has the function of an evaporator, and the condenser 7 are connected by an outgoing pipe 5 and a return pipe 6 to form a closed circuit, and an expansion valve 8 is arranged in the return pipe 6, and the outgoing pipe 5 accumulator 9
and a compressor 10, and furthermore, a hot water storage tank 1 and a pump 4.
and condenser 7 were connected in order through piping in a closed circuit.

In the above configuration, by operating the compressor 10,
The pressure inside the heat collector 3 is reduced to evaporate the low-temperature latent heat medium, the accumulator 9 separates gas and liquid, the compressor 10 converts it into high-temperature, high-pressure steam, and the condenser 7 condenses the stored hot water, which is circulated by the pump 4. Water is heated and heat is stored in hot water tank 1. On the other hand, the latent heat medium, which has become a high-pressure liquid, is expanded by an expansion valve 8 whose opening degree is adjusted according to the signal from the temperature sensing part 11. This means that even when solar radiation is weak, atmospheric heat can be collected from the air, making it possible to maintain a constant hot water storage temperature regardless of the presence or absence of solar radiation. However, with this configuration, even when there is strong solar radiation, the compressor 10 is installed in the heat collecting area.
This has the problem of creating a system with high power consumption, which means high running costs.

The purpose of the invention is to solve such conventional problems, and when the solar radiation is strong, the power consumption required for heat collection is reduced to zero, and
The purpose is to store hot water at a temperature higher than a certain value even in the absence of solar radiation.

Structure of the Invention To achieve this object, the present invention connects a heat collector for absorbing solar heat and atmospheric heat and a heat exchanger for heat radiation in a closed circuit, and a working fluid as a latent heat medium is installed inside the heat collector. At the same time, a control tank is installed above the heat collector to circulate the working fluid in the pipeline by gravity, forming a heat collecting circuit, and an evaporator to cool the working fluid in the heat collecting circuit is installed in the return pipe. A condenser that heats the working fluid is installed in the outgoing pipe, and an evaporator and
A heat pump circuit is constructed by connecting a compressor, a condenser, and an expansion valve in order through piping in a closed circuit.

With this configuration, sunlight is strong and the temperature inside the hot water tank is low.
If the conditions are such that solar heat can be collected with high efficiency, such as when the air temperature is high, the compressor of the heat pump circuit can be stopped and only the heat collection circuit can be operated without using power from other sources. First, solar heat can be collected highly efficiently with zero running costs. On the other hand, in conditions where solar heat cannot be collected efficiently, such as with weak sunlight, high temperature inside the hot water tank, and low air temperature, the heat pump circuit's evaporator can be operated by operating the heat pump circuit's compressor. The working fluid in the return pipe of the heat collecting circuit is cooled in the heat collecting circuit, and the working fluid in the outgoing pipe is heated in the condenser, so the working fluid circulates in the heat collecting circuit, and the temperature of the working fluid entering the heat collector becomes the air temperature. By making it lower, it becomes possible to collect atmospheric heat and solar heat in the collector.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. 1st
In the figure, a heat exchanger 2 and a heat collector 3 installed in a hot water storage tank 11 are connected to an outgoing pipe 5 and a returning pipe 6 via a control tank 12.
The heat collecting circuit 13 is configured by being connected by piping in a closed circuit. The control tank 12 consists of an upper chamber 1'4 and a lower chamber 15, and has a connection port 16 that connects the upper chamber 14 and the lower chamber 15.
The valve 18 is provided with a valve 18 which is pushed up by a float 17 which is freely movable within the lower chamber 15 and becomes open in this case. In addition, the lower chamber 15 and the heat collector 3 are the return pipe 1
91, and a first check valve 20 is provided in the middle thereof, and the upper chamber 14 and the heat collector 3 are connected by a communication pipe 21, and a gas-liquid separator 22 is provided in the middle thereof. In the heat collecting circuit 13, a second check valve 22 is provided in the middle of the outgoing pipe 5 that connects the gas-liquid separator 22 and the heat exchanger 2, and a return pipe that connects the heat exchanger 2 and the lower chamber 15 is provided. A third check valve 23 is provided in the middle of the valve 6.

On the other hand, an evaporator 24 for cooling the working fluid of the latent heat medium of the heat collecting circuit 13 is disposed in the return pipe 6, and a condenser 7 for heating the working fluid is disposed in the outgoing pipe 51. , the accumulator 9, the compressor 10, the condenser 7, and the expansion valve 8 whose opening degree is adjusted in response to a signal from a temperature sensing section 11 that detects the outlet temperature of the evaporator 24 are connected by piping in a closed circuit in order. A heat pump circuit 25 is configured. Note that the same members as in FIGS. 1, 2, and 3 are given the same numbers.

In the above configuration, if the conditions are such that solar heat can be collected with high efficiency, such as strong sunlight, low temperature in the hot water storage tank 1, and high air temperature, the compressor 1 of the heat pump circuit 25
When the operation of the 0 is stopped, the working fluid in the heat collector 3 is heated and evaporated, and the internal pressure increases, so the high temperature working fluid is separated from the vapor by the gas-liquid separator 221, and only the liquid is sent to the outgoing pipe. 5
The heat flows through the heat exchanger 21 and releases heat. The working fluid cooled by the heat exchanger 2 passes through the return pipe 6 and enters the control tank 12.
The water flows into the lower chamber 15 and pushes up the float 1.

When the level of the working fluid in the control tank 12 rises and the float 17 rises, the valve 18 is pushed up and the connection port 16 is opened.The pressures in the heat collector 3 and the lower chamber 15 become approximately the same value1. Therefore, due to gravity f, the working fluid in the lower chamber 15 is returned to the heat collector 3 through the return pipe 19. However, the level of the hydraulic fluid in the lower chamber 15 is lowered and the float 17
When the valve 18 closes the connection port 16 by pressing down, the working fluid is again sent under pressure from the heat collector 3 to the heat exchanger 2, and heat transfer is performed.

Thereafter, the same operation is repeated, whereby the solar heat obtained by the heat collector 3 is transferred to the hot water storage tank 1 without requiring power from other sources.

On the other hand, if the solar radiation is weak, or if the temperature inside the hot water tank 1 is high and the air temperature is low, it is not possible to collect solar heat with high efficiency, the compressor 1 of the heat pump circuit 25
0, solar heat and atmospheric heat are collected in the heat collector 3. That is, heat pump circuit 2
The evaporator 24 of No. 5 cools the working fluid flowing through the return pipe 6 of the heat collecting circuit 13 to make the temperature of the working fluid lower than the air temperature, and the heat obtained from the evaporator 24 is transferred to the condenser 7.
As heat is radiated to the working fluid flowing through the outgoing pipe 5, the pressure inside the outgoing pipe 5 increases, and the working fluid is pushed out to the lower chamber 15 of the control tank 12. As a result, the working fluid circulates within the heat collection circuit, and the temperature within the hot water tank 1 can be raised via the heat exchanger 2.

Therefore, if it is not possible to collect solar heat with high efficiency, by operating the heat pump circuit 25, the temperature of the working fluid flowing into the heat collector 3 is made lower than the air temperature, and at the same time,
By making the temperature flowing into the heat exchanger 21 higher than the temperature in the hot water storage tank 1, it is possible to collect heat from solar heat and atmospheric heat in the heat collector 3, and transport the heat to the hot water storage tank 11 for heat storage.

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

(1) The heat pump circuit is configured to have an evaporation stage in contrast to the heat collecting circuit that can circulate the working fluid without relying on power from another source, so by operating the heat pump circuit, the working fluid flowing through the return pipe is cooled. However, it is possible to heat the working fluid flowing through the outbound pipe, and it is possible to collect both solar heat and atmospheric heat. Therefore, when solar radiation is strong and solar heat can be collected with high efficiency, it is possible to collect heat without consuming electricity by stopping the operation of the heat pump circuit.
On the other hand, if solar radiation is weak and solar heat cannot be collected with high efficiency,
By adding operation to the compressor of the heat pump circuit, both solar heat and atmospheric heat can be collected at low running costs, ensuring a certain amount of heat collection regardless of the presence or absence of solar radiation. I can do it.

(2) The heat collection circuit and heat pump 1 circuit are each independent.
In addition, there is no need to extend the piping of the heat pump circuit to a heat collector installed in a remote location such as on the roof, and the heat pump circuit can be configured as a closed circuit. Since the pressure drop caused by piping can be reduced, highly efficient heat pump operation is possible, and only the 18-sou (3) heat collecting circuit can be operated independently, even in conditions of low air temperature where heat pump operation is not possible. When sunlight is strong, heat can be collected without consuming electricity.

[Brief explanation of drawings]

Figure 1 is a block diagram showing an embodiment of the solar heat collector of the present invention, Figure 2 is a block diagram of a conventional solar heat collector, and Figure 3 is the configuration of a conventional solar heat collector using a heat pump. It is a diagram. 2- Heat exchanger, 3 - Heat collector, 5 - Outgoing pipe, 6-...
Return pipe, 7... Condenser, 8... Expansion valve, 1° compressor,
12 ... Control tank, 13 ... Heat collection circuit, 19
・Return pipe, 20 ・First check valve, 22・Second check valve,
24...Evaporator, 25...Heat pump circuit. Name of agent: Patent attorney Toshio Nakao and 1 other person 2nd
figure

Claims (1)

[Claims] A heat collector that absorbs solar heat and atmospheric heat, a heat exchanger for heat radiation, an outgoing pipe and a return pipe that connect the heat collector and the heat exchanger in a closed circuit, and a latent heat sealed inside. a control tank that circulates the working fluid as a medium and the working fluid in a pipe line provided above the heat collector without power; a return pipe that connects the control tank and the heat collector; and the return pipe. and a first and second check valve provided in the middle of the return pipe; an evaporator disposed in the return pipe of the heat collection circuit that absorbs heat from the working fluid; A solar heat collecting device comprising a heat pump circuit configured by sequentially connecting a condenser, a condenser disposed in the outgoing pipe of the heat collecting circuit to radiate heat to the working fluid, and an expansion valve in a closed circuit.