JPS6146742B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a solar heat collector.

[Conventional technology]

Conventional solar heat collection equipment installs a temperature sensor in the water collection pipe of the heat collection plate, and when the temperature sensor detects a freezing temperature around 0℃, it operates a circulation pump to circulate hot water in the heat storage material. Some devices are known that prevent freezing by heating the heat collecting plate.

[Problem to be solved]

In the above solar heat collector, even if there is a cold air mass in the sky and the heat is dissipated from the heat collecting plate, and the temperature of the collecting pipe is quite high, the heat collecting plate may freeze. There are cases where the high temperature water in the heat storage tank leaks into the hot water collection pipe due to foreign matter caught in the check valve of the heat transfer pipe, and the hot water collection pipe remains hot even though the heat collection plate is at a low temperature. In some cases, the anti-freeze function did not function adequately.

[Means for solving problems]

The present invention has been developed as a result of intensive research into a solar heat collector that eliminates the drawbacks of the conventional devices and has a reliable freeze-breakage prevention function.The present invention has a simple structure and uses special expensive components for existing solar heat collectors. The purpose of the present invention is to provide a solar heat collecting device that does not require complicated control circuits.
A resistance change type temperature sensor is provided in each of the hot water collection pipe and the heat storage tank of the heat collection plate, and the resistance signal of the temperature sensor is received, and the resistance signals of both temperature sensors are compared to determine the temperature of the hot water collection pipe. A first comparison section that sends an output signal to operate the circulation pump when the temperature is more than a predetermined temperature difference than the temperature of the tank, and a resistance signal of a temperature sensor installed in the hot water collection pipe that is at a temperature below the predetermined temperature. In the solar heat collecting device, the solar heat collecting device includes a control part provided with a second comparison part that sends an output signal for operating a circulation pump, the heat collecting part of the heat collecting plate has a temperature substantially equal to the predetermined temperature. A temperature-sensitive switch that operates based on temperature is provided, and the temperature-sensitive switch is connected to the temperature sensor so that the resistance signal of the temperature sensor provided in the hot water collection pipe is forced to be a resistance signal of a temperature below the predetermined temperature. A solar heat collecting device characterized by:

[Effect]

A temperature-sensitive switch installed in the heat collection part of the heat collection plate operates at approximately the same temperature as a predetermined temperature, and changes the resistance signal of the temperature sensor installed in the hot water collection pipe to a resistance signal at a temperature below the predetermined temperature. Short circuit or disconnect the temperature sensor.

〔Example〕

Hereinafter, an example of the solar heat collecting device of the present invention will be explained in detail based on the drawings.

FIG. 1 is a block diagram showing the overall configuration of the solar heat collector of the present invention, in which heat medium pipes are shown by solid lines and electric circuits are shown by dotted lines.

In Figure 1, 1 is a heat collecting plate that collects solar heat, and 2 is made of a material that absorbs sunlight well.
A large number of grooves are formed substantially parallel in the vertical direction on each of the plate bodies, and the grooves are opposed to each other to form a plurality of vertical heat medium flow passages, and each of the heat medium flow passages is The upper open end is connected and communicated with the hot water collection pipe 2, and the lower open end is connected and communicated with the water distribution pipe 14.

A plurality of heat collecting plates 1, 1...... are arranged in parallel on the roof of a building, etc., and the respective hot water collection pipes 2, 2...... are connected to each other and the water pipes 14, 14...... are connected to each other. .

Connected heat collecting plates 1, 1... Heat collecting pipes 2, 2...
...... and the other end of the water pipes 14, 14... are connected to the heat medium pipes 3, 3, respectively, and the other end of the heat collecting pipes 2, 2...... and the water pipe 14 ,14...
One end of each is closed.

The heat medium pipe 3 connected to the water distribution pipe 14 is connected to the circulation pump 4
The heat medium pipe 3 is connected to the bottom of the heat storage tank 5 via a check valve 6, and is connected to the heat collecting pipe 2, and the heat medium pipe 3 is connected to the upper part of the heat storage tank 5 via a check valve 6.
and a hot water supply pipe 8 are connected.

A variable resistance temperature sensor 10 is inserted into one end of the heat collecting pipe 2, and a variable resistance temperature sensor 11 is also inserted into the lower part of the heat storage tank 5.
The temperature sensors 10, 11 and the control section 12 are connected by electric wires.

The control unit 12 receives the resistance signals transmitted from the temperature sensors 10 and 11, compares both resistance signals, and determines that the resistance signal of the temperature sensor 10 is the same as that of the temperature sensor 1.
The temperature difference value is set when the temperature is higher than the resistance signal of 0 and a certain amount of heat collection is expected from that temperature difference.
A first comparison section (not shown) is provided that outputs a control signal to drive the circulation pump 4 when there is a temperature difference greater than or equal to the temperature difference value, and the electric wire to which the control signal is transmitted is connected to the electric motor of the circulation pump 4. (not shown) and the control unit 12 are connected.

Furthermore, the control unit 12 is provided with a second comparison unit (not shown), and the second comparison unit is configured to calculate the temperature immediately before freezing of the heat medium, for example, 0 when the heat medium is water.
℃, and when the resistance signal of the temperature sensor 10 reaches a temperature below the set temperature, a control signal for driving the circulation pump 4 is output.

Furthermore, temperature-sensitive switches 13, 13... are provided approximately at the center of the heat-collecting portions of the heat-collecting plates 1, 1, respectively, and are connected to the temperature sensor 10. Even if the resistance signal of the temperature sensor 10 is above the set temperature, if the temperature-sensitive switch 13 provided on a certain heat collecting plate 1 detects that the temperature is below the set temperature, the temperature will be changed. A control signal for driving the circulation pump 4 is output by forcing the resistance signal of the sensor 10 to be a resistance signal below a set temperature.

The temperature sensitive switch 13, for example a bimetal or ferrite switch, can be suitably used.

In the solar heat collecting device of the present invention, the heat medium is usually water, but it is also possible to use an antifreeze solution mixed with an antifreeze agent or an organic solvent such as liquid paraffin.

As described above, since the freezing temperature differs when a heat medium other than water is used, it is preferable to match the set temperature of the second comparison section to that heat medium.

The heat medium flows from the bottom of the heat storage tank 5 through the heat collection plate 1 by the circulation pump 4, collects solar heat, and returns to the top of the heat storage tank 5.

An air vent 9 is provided at the connecting portion of the heat collecting plate 1 between the hot water collection pipe 2 and the heat medium pipe 3.

The air vent 9 is used to suck air when the inside of the heat medium pipe 3 is in a reduced pressure state to restore the reduced pressure state.

Furthermore, the relationship between the temperature sensor 10 and the temperature-sensitive switch 13 will be explained in detail based on FIGS. 2, 3, 4, and 5.

The temperature sensor 10 shown in FIG. 2 is a variable resistance temperature sensor using a copper wire or the like having positive characteristics, as shown by line A in FIG. 3, and has a resistance value of 2000Ω at 0°C. Since it has, the control unit 12
If the setting value of the second comparison section is set to 2000Ω, the temperature will be 0℃ as shown by the vertical arrow in Figure 3.
This means that it is set to .

The temperature-sensitive switch 13 has an a contact that operates and closes when the temperature is above 0°C, which is the same as the set temperature, and returns and closes when the temperature drops below 0°C, and a b contact that operates in the opposite way to the a contact. has been done.

The b contact of the temperature sensitive switch 13 is the temperature sensor 1.
0 is shown connected in parallel with 0.

With this configuration, even if the temperature of the heat collecting pipe 2 does not fall below the set temperature of 0°C and the temperature of the heat collecting plate 1 falls below 0°C, the temperature sensitive switch 13 will detect this. Recovered, temperature sensor 10
As a result, the resistance value becomes approximately 0Ω on the extension of line A in Figure 3, and a low temperature resistance signal of 0°C or less is forcibly transmitted. Comparison part is circulation pump 4
A control signal for driving the circulation pump 4 is output, and the circulation pump 4 starts operating to prevent freezing.

The temperature sensor 10 shown in FIG. 4 is a variable resistance temperature sensor such as a thermistor with negative characteristics as shown by line A in FIG. 5, and has a resistance value of 2000Ω at 0°C. Therefore, control unit 1
If the setting value of the second comparison section of 2 is set to 2000Ω, the temperature will be 0 as shown by the vertical arrow in Figure 5.
This means that the temperature is set to ℃.

The temperature-sensitive switch 13 is the same as described above, and the a-contact point of the temperature-sensitive switch 13 is shown connected in series with the temperature sensor 10.

With this configuration, even if the temperature of the heat collecting pipe 2 does not fall below the set temperature of 0°C and the temperature of the heat collecting plate 1 falls below 0°C, the temperature sensitive switch 13 will detect this. Recovered, temperature sensor 10
The A contact that connects will open and be disconnected, resulting in an almost infinite resistance value on the extension of line B in Figure 5, and a low temperature resistance signal below 0°C will be forcibly transmitted. Enforcement unit 12 that received this
The second comparison section outputs a control signal to drive the circulation pump 4, and the circulation pump 4 starts operating to prevent freezing.

〔effect〕

As detailed above, the solar heat collecting device of the present invention has the above structure, so when the heat collecting plate is cooled down to a low temperature of, for example, 0°C or less, the temperature-sensitive switch senses this. Since the resistance signal of the temperature sensor is forced to be a low temperature resistance signal of 0°C or less, the control unit outputs a control signal to drive the circulation pump, and the circulation pump is operated, so the heat medium is circulated. This warms the heat collecting plate and prevents it from freezing and breaking.

Further, in the solar heat collecting device of the present invention, unlike the conventional method of controlling the heat medium temperature of the hot water collecting pipe of the heat collecting plate, malfunctions and delays in the freeze-break prevention signal do not occur.

In addition, in the solar heat collecting device of the present invention, a variable resistance temperature sensor is provided in the water collecting pipe of the heat collecting plate, and if there is an existing solar heat collecting device having an antifreeze circuit,
All you have to do is connect the temperature-sensitive switch in parallel or series with the temperature sensor of the water collection pipe, depending on the characteristics of the temperature sensor, and it is possible to provide a reliable freeze-break prevention function to the existing solar heat collection device with simple work. I can,
This is extremely useful in practice.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing an example of the solar heat collecting device of the present invention, Figs. 2 and 4 are electrical circuit diagrams showing the main parts of the solar heat collecting device of Fig. 1, and Fig. 3 is a block diagram showing an example of the solar heat collecting device of the present invention. , FIG. 5 is a graph explaining the operating principle of FIG. 4. Explanation of symbols, 1... Heat collection plate, 2... Hot water collection pipe, 3
... Heat medium pipe, 4 ... Circulation pump, 5 ... Heat storage tank,
6...Check valve, 7...Water supply pipe, 8...Hot water supply pipe, 9
... Air vent, 10, 11 ... Resistance change type temperature sensor, 12 ... Control section, 13 ... Temperature-sensitive switch, 14 ... Water pipe.

Claims (1)

[Scope of Claims] 1. A heat collection plate, a heat storage tank, and a circulation pump are connected by a heat medium pipe, and a resistance change type temperature sensor is provided in each of the heat collection plate, hot water collection pipe, and heat storage tank, and the temperature sensor receives the resistance signal of the temperature sensor, compares the resistance signals of both temperature sensors, and sends an output signal to operate the circulation pump when the temperature of the hot water collection pipe is higher than the temperature of the heat storage tank by a predetermined temperature difference or more. a first comparison section;
A solar heat collection device comprising a control section provided with a second comparison section that sends an output signal to operate a circulation pump when the resistance signal of a temperature sensor installed in the hot water collection pipe is below a predetermined temperature. In the device,
A temperature-sensitive switch that operates at approximately the same temperature as the predetermined temperature is provided in the heat-collecting portion of the heat-collecting plate, and a resistance signal of a temperature sensor provided in the hot water collection pipe forces the temperature-sensitive switch to reach the predetermined temperature. A solar heat collector, characterized in that the solar heat collecting device is connected to the temperature sensor so as to provide a resistance signal of a temperature below the temperature. 2 The temperature sensor has a positive characteristic, and the temperature-sensitive switch has an a contact that closes when activated and opens when the switch returns, and a b contact that operates in the opposite way to the a contact, and the b contact is connected in parallel with the temperature sensor. A solar heat collecting device according to claim 1, which is connected to a solar heat collector. 3 The temperature sensor has a negative characteristic, and the temperature-sensitive switch has an A contact that closes when activated and opens when the switch returns, and a B contact that operates in the opposite way to the A contact, and the A contact is connected in series with the temperature sensor. A solar heat collecting device according to claim 1, which is connected to a solar heat collector.