JPS6161023B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a solar heat collector that collects solar heat using a circulation circuit in which a heat medium that can be converted into a gas-liquid two-phase heat medium is enclosed.

As shown in FIG. 1, this type of conventional solar heat collecting device has a solar heat collector 1, a condenser 3 inserted into a heat storage tank 2, a heat collecting outgoing pipe 4 and a heat collecting return pipe 5, which form an annular structure. are connected to form a circulation circuit 6, and a circulation pump 7 is inserted into the heat collection outgoing pipe 4. The circulation circuit 6 is sealed with a heat medium (for example, a fluorocarbon refrigerant) 8 that can be changed into a gas-liquid two-phase state. The heat medium 8 is evaporated by collecting solar heat in the solar heat collector 1, and the evaporated gas returns to the condenser 3 through the heat collection return pipe 5, where it is transferred to the solar heat collector 1. It is condensed and liquefied. Thereafter, by repeating this process, the liquid to be heated (for example, water) 9 stored in the heat storage tank 2 is heated by absorbing the latent heat of the heat medium 8 in the condenser 3.

The circulation pump 7 is equipped with a temperature sensor 10 that detects the temperature of the solar heat collector 1 and the temperature inside the heat storage tank 2, respectively.
11, a control device 12 that issues an on signal when the temperature of the solar heat collector 1 is higher than the internal temperature of the heat storage tank 2 by a certain value or more, and issues an off signal when the temperature difference disappears.
The operation is controlled by

By the way, when there is no sunlight and the temperature of the solar heat collector 1 becomes lower than the temperature inside the heat storage tank 2, the solar heat collector 1 is cooled by the atmosphere and radiation cooling occurs, and the inside of the solar heat collector 1 is The pressure decreases as the heat medium 8 condenses and liquefies. Therefore, the heat medium 8 in the condenser 3 removes latent heat from the heated liquid in the heat storage tank 2 and evaporates into vapor, and the evaporated gas passes through the heat collection return pipe 5 or the heat collection outgoing pipe 4 to the solar heat collector. 1 and it becomes condensed here, which has the drawback of letting much of the thermal energy from the sun's heat escape.

The present invention has been made in view of the above-mentioned facts, and is a method for transferring heat medium from the condenser to the solar heat collector when there is no sunlight and the temperature of the solar heat collector becomes lower than the temperature inside the heat storage tank. In addition to preventing the thermal energy in the heat storage tank from being lost,
Even if the solar heat collector becomes dry and an abnormal pressure rise occurs, this can be absorbed and the circuit will not be damaged.

Hereinafter, one embodiment of the present invention will be described based on the drawings. FIG. 2 shows the solar heat collecting device of the present invention,
The same parts as in Fig. 1 are given the same reference numerals, and the difference from Fig. 1 is the heat collection outgoing pipe that connects the solar heat collector 1 and the condenser 3 inserted into the heat storage tank 2. 4, a solenoid valve 13 is inserted together with the circulation pump 7, and a solenoid valve 14 is inserted into the heat collection return pipe 5. The electromagnetic valves 13 and 14 are energized and opened and closed together with the circulation pump 7 by the control device 12.

The solenoid valves 13 and 14 are well-known ones as shown in FIG. A valve seat 19 fixed to the coil 16 moves upward to communicate the A port and B port, and the valve seat 19 blocks both ports A and B when the coil 16 is not energized. As is clear from the figure, when excessive pressure is applied to the A port, the valve seat 19 and the plunger 17 are pushed up, allowing the A and B ports to communicate with each other. In the embodiment shown in FIG. 2, the solenoid valves 13 and 14 are both connected so that the A port is on the solar heat collector 1 side.

According to the embodiment of the present invention, during the day when there is sunlight, the temperature of the solar heat collector 1 becomes higher than the temperature inside the heat storage tank 2, and the control device 12 operates the circulation pump 7 to turn off the electromagnetic Valves 13 and 14 are opened. Therefore, the condensed and liquefied heat medium 8 in the condenser 3 is transferred to the solar heat collector 1 by the circulation pump 7, and the heat medium 8 evaporated and vaporized in the solar heat collector 1 is supplied to the condenser 3. The heated liquid 9 in the heat storage tank 2 is heated.

When there is no sunlight and the temperature of the solar heat collector 1 becomes lower than the internal temperature of the heat storage tank 2, the circulation pump 7 stops and the solenoid valves 13 and 14 close. Therefore, even when the solar heat collector 1 is cooled at night and the pressure inside the solar heat collector 1 becomes low due to condensation and liquefaction of the heat medium 8, there is no movement of the heat medium 8 from the condenser 3, and the pressure inside the solar heat collector 1 is low. There is only movement of the heat medium in the piping between the solar heat collector 1 and the electromagnetic valves 13 and 14, and there is no loss of thermal energy in the heat storage tank 2 due to heat radiation.

If there is a power outage or a failure of the solenoid valves 13 and 14,
The solenoid valves 13 and 14 remain closed, and
When there is sunlight, the solar heat collector 1 becomes dry and the internal pressure of the solar heat collector 1 becomes abnormally high. Because of the communication, the high pressure gas is supplied to the condenser 3 and condensed.
The solar heat collector 1, the heat collection outgoing pipe 4, and the heat collecting return pipe 5 will not be damaged due to abnormal pressure rise due to dry firing.

In addition, in the above-mentioned embodiment, the solenoid valves 13 and 14
Although two solenoid valves 13 of the heat collection outgoing pipe 4 are used, the solenoid valve 13 of the heat collection outgoing pipe 4 can be omitted if it has a structure that blocks the flow of the heat medium when the circulation pump 7 is stopped. Moreover, although the A ports of both the electromagnetic valves 13 and 14 are connected to the solar heat collector 1 side, it is sufficient that at least one A port is connected to the solar heat collector 1 side.

As described above, the present invention connects a solar heat collector and a condenser inserted in a heat storage tank in a ring shape via a circulation pump, and transfers the heat medium condensed and liquefied in the condenser using the circulation pump. It is equipped with a circulation circuit that heats the liquid to be heated in the heat storage tank by returning the heat medium evaporated in the solar heat collector to the condenser, and the circulation circuit has a circuit in which the temperature of the solar heat collector is equal to the temperature inside the heat storage tank. A solenoid valve is inserted to prevent the heat medium in the condenser from moving to the solar heat collector when the temperature drops further, so when there is no sunlight, the heat medium in the condenser will not move to the solar heat storage tank. The latent heat is taken away from the liquid to be heated, and the heat energy obtained by collecting solar heat can be effectively used without being dissipated in a solar heat collector. In addition, when the pressure of the solar heat collector rises abnormally, the heat medium in the solar heat collector is released to the condenser via the solenoid valve, regardless of whether the solenoid valve is energized or not, so there will be no power outage. Even if a failure occurs in the solenoid valve or solenoid valve, damage to the solar heat collector and piping due to dry firing can be prevented.

[Brief explanation of the drawing]

Figure 1 is a system diagram of a conventional solar heat collector.
FIG. 2 is a system diagram of a solar heat collector according to an embodiment of the present invention, and FIG. 3 is a sectional view of the solenoid valve used in FIG. 2. 1... Solar heat collector, 2... Heat storage tank, 3... Condenser, 6... Circulation circuit, 7... Circulation pump, 8...
...Heating medium, 9...Liquid to be heated, 13, 14...Solenoid valve (on-off valve).

Claims (1)

[Claims] 1. A solar heat collector and a condenser inserted into a heat storage tank are connected in a ring through a circulation pump, and the heat medium condensed and liquefied in the condenser is transferred to the solar heat collector using the circulation pump. , a solar heat collector equipped with a circulation circuit that heats the liquid to be heated in the heat storage tank by returning the heat medium evaporated in the solar heat collector to the condenser. When the temperature drops below the temperature inside the heat storage tank, a solenoid valve is inserted to prevent the heat medium in the condenser from moving to the solar heat collector, and this solenoid valve becomes de-energized when the solar heat collector's pressure rises abnormally. Regardless, a solar heat collector is characterized in that the heat medium of the solar heat collector is released to a condenser.